930 resultados para Bottom-up filter


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Sedentary consumers play an important role on populations of prey and, hence, their patterns of abundance, distribution and coexistence on shores are important to evaluate their potential influence on ecosystem dynamics. Here, we aimed to describe their spatio-temporal distribution and abundance in relation to wave exposure in the intertidal rocky shores of the south-west Atlantic to provide a basis for further understanding of ecological processes in this system. The abundance and composition of the functional groups of sessile organisms and sedentary consumers were taken by sampling the intertidal of sheltered and moderately exposed shores during a period of one year. The sublittoral fringe of sheltered areas was dominated by macroalgae, while the low midlittoral was dominated by bare rock and barnacles. In contrast, filter-feeding animals prevailed at exposed shores, probably explaining the higher abundance of the predator Stramonita haemastoma at these locations. Limpets were more abundant at the midlittoral zone of all shores while sea urchins were exclusively found at the sublittoral fringe of moderately exposed shores, therefore, adding grazing pressure on these areas. The results showed patterns of coexistence, distribution and abundance of those organisms in this subtropical area, presumably as a result of wave action, competition and prey availability. It also brought insights on the influence of top-down and bottom-up processes in this area.

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In this manuscript we briefly describe bipolar disorder (a depressive and manic mental disease), its classification, its effects on the patient, which sometimes include suicidal tendencies, and the drugs used for treatment. We also address the status quo with regard to diagnosis of bipolar disorder and recent advances in bioanalytical approaches for biomarker discovery. These approaches focus on blood samples (serum and plasma) and proteins as the main biomarker targets, and use various strategies for protein depletion. Strategies include use of commercially available kits or other homemade strategies and use of classical proteomics methods for protein identification based on bottom-up or top-down approaches, which used SELDI, ESI, or MALDI as sources for mass spectrometry, and up-to-date mass analyzers, for example Orbitrap. We also discuss some future objectives for treatment of this disorder and possible directions for the correct diagnosis of this still-unclear mental illness.

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Benthic marine invertebrates may form metapopulations connected via propagule dispersal. Conservation efforts often target potential source coastlines to indirectly benefit areas depending on allochthonous offspring production. Besides population density, adult size structure, sex ratio, brooding frequency and the proportion of breeding individuals may significantly influence the reproductive output of benthic populations, but these effects have seldom been tested. We used rocky shore crabs to assess the spatial variability of such parameters at relevant scales for conservation purposes and to test their consistency over 2 consecutive years; we then used the data to address whether bottom-up processes or biological interactions might explain the patterns observed. We decomposed egg production rates into their components for the 2 most abundant brachyuran species inhabiting the intertidal rocky habitat. Adult density and brooding frequency varied consistently among shores for both species and largely explained the overall spatial trends of egg production. Temporally consistent patterns also included among-shore differences in the size of ovigerous females of the grapsid Pachygrapsus transversus and between-bay differences in the fecundity of the spider crab Epialtus brasiliensis. Sex ratio was remarkably constant in both. We found no positive or negative correlations between adult density and brooding frequency to support either the existence of a component Allee effect (lack of mate encounters) or an effect of intra-specific competition. Likewise, shore-specific potential growth in P. transversus does not negatively correlate with frequency of ovigerous individuals, as would be expected under a critical balance between these 2 processes. The patterns observed suggest that bottom-up drivers may best explain spatial trends in the reproductive output of these species.

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This is a draft for a chapter of the book version of my Ph.D thesis. The chapter addresses the following question: Are the creative processes of musical composers and academic economists essentially the same, or are there significant differences? The paper finds that there are deep similarities between the creative processes of theoretical economists and the creative processes of artists. The chapter builds a process oriented lifecycle account of creative activity, drawing on testimonial material from the arts and the sciences, and relates the model to the creative work of economists developing economic theory.

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“Closing the gap in curriculum development leadership” is a Carrick-funded University of Queensland project which is designed to address two related gaps in current knowledge and in existing professional development programs for academic staff. The first gap is in our knowledge of curriculum and pedagogical issues as they arise in relation to multi-year sequences of study, such as majors in generalist degrees, or core programs in more structured degrees. While there is considerable knowledge of curriculum and pedagogy at the course or individual unit of study level (e.g. Philosophy I), there is very little properly conceptualised, empirically informed knowledge about student learning (and teaching) over, say, a three-year major sequence in a traditional Arts or Sciences subject. The Carrick-funded project aims to (begin to) fill this gap through bottom-up curriculum development projects across the range of UQ’s offerings. The second gap is in our professional development programs and, indeed, in our recognition and support for the people who are in charge of such multi-year sequences of study. The major convener or program coordinator is not as well supported, in Australian and overseas professional development programs, as the lecturer in charge of a single course (or unit of study). Nor is her work likely to be taken account of in workload calculations or for the purposes of promotion and career advancement more generally. The Carrick-funded project aims to fill this gap by developing, in consultation with crucial stakeholders, amendments to existing university policies and practices. The attached documents provide a useful introduction to the project. For more information, please contact Fred D’Agostino at f.dagostino@uq.edu.au.

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Contemporary strategies for rural development in Australia are based upon notions of self-help and bottom-up, community-based initiatives which are said to 'empower' the individual from the imposing structures of government intervention. While such strategies are not entirely new to Australia, they have, it seems, been inadequately theorised to date and are generally regarded, in rather functionalist terms, as indicative of attempts to cut back on public expenditure. Harnessing itself to the 'governmentality' perspective, this paper explores government and 'expert' discourses of rural community development in Queensland and suggests, instead, that these strategies are indicative of an advanced liberal form of rule which seeks to 'govern through community'. With this in mind, three basic research questions are identified as worthy of further exploration; how are the notions of self-governing individuals and communities constructed in political discourse; what political rationalities are used to justify current levels of(non) intervention and finally; what are the discourses, forms and outcomes of empowerment at the local level? The paper concludes by arguing that while the empowering effects of self-help are frequently cited as its greatest virtue, it is not so much control as the added burden of responsibility that is being devolved to local people. Given the emphasis of the governmentality perspective on strategies for 'governing at a distance', however, these conclusions can hardly be unexpected. (C) 2000 Elsevier Science Ltd, All rights reserved.

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In this paper we present some result on sol-gel derived silica-hafnia systems. In particular we focus on fabrication, morphological and spectroscopic assessment of Er(3+)-activated thin films. Two examples of silica-hafnia-derived waveguiding glass ceramics, prepared by top-down and bottom-up techniques are reported, and the main optical properties are discussed. Finally, some properties of activated microspherical resonators, having a silica core, obtained by melting the end of a telecom fiber, coated with an Er(3+)-doped 70SiO(2)-30HfO(2) film, are presented. (C) 2009 Elsevier B.V. All rights reserved.

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The study reported here is a classical bottom-up proteomic approach where proteins from wasp venom were extracted and separated by 2-DE; the individual protein spots were proteolytically digested and subsequently identified by using tandem mass spectrometry and database query with the protein search engine MASCOT. Eighty-four venom proteins belonging to 12 different molecular functions were identified. These proteins were classified into three groups; the first is constituted of typical venom proteins: antigens-5, hyaluronidases, phospholipases, heat shock proteins, metalloproteinases, metalloproteinase-desintegrin like proteins, serine proteinases, proteinase inhibitors, vascular endothelial growth factor-related protein, arginine kinases, Sol i-II and -II like proteins, alpha-glucosidase, and superoxide dismutases. The second contained proteins structurally related to the muscles that involves the venom reservoir. The third group, associated with the housekeeping of cells from venom glands, was composed of enzymes, membrane proteins of different types, and transcriptional factors. The composition of P. paulista venom permits us to hypothesize about a general envenoming mechanism based on five actions: (i) diffusion of venom through the tissues and to the blood, (ii) tissue, (iii) hemolysis, (iv) inflammation, and (v) allergy-played by antigen-5, PLA1, hyaluronidase, HSP 60, HSP 90, and arginine kinases.

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Background: Bipolar disorder is frequently misdiagnosed as major depressive disorder, delaying appropriate treatment and worsening outcome for many bipolar individuals. Emotion dysregulation is a core feature of bipolar disorder. Measures of dysfunction in neural systems supporting emotion regulation might therefore help discriminate bipolar from major depressive disorder. Methods: Thirty-one depressed individuals-15 bipolar depressed (BD) and 16 major depressed (MDD), DSM-IV diagnostic criteria, ages 18-55 years, matched for age, age of illness onset, illness duration, and depression severity-and 16 age- and gender-matched healthy control subjects performed two event-related paradigms: labeling the emotional intensity of happy and sad faces, respectively. We employed dynamic causal modeling to examine significant among-group alterations in effective connectivity (EC) between right- and left-sided neural regions supporting emotion regulation: amygdala and orbitomedial prefrontal cortex (OMPFC). Results: During classification of happy faces, we found profound and asymmetrical differences in EC between the OMPFC and amygdala. Left-sided differences involved top-down connections and discriminated between depressed and control subjects. Furthermore, greater medication load was associated with an amelioration of this abnormal top-down EC. Conversely, on the right side the abnormality was in bottom-up EC that was specific to bipolar disorder. These effects replicated when we considered only female subjects. Conclusions: Abnormal, left-sided, top-down OMPFC-amygdala and right-sided, bottom-up, amygdala-OMPFC EC during happy labeling distinguish BD and MDD, suggesting different pathophysiological mechanisms associated with the two types of depression.

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Objective: Verify the influence of radiant exposure (H) on composite degree of conversion (DC) and mechanical properties. Methods: Composite was photoactivated with 3, 6, 12, 24, or 48 J/cm(2). Properties were measured after 48-h dry storage at room temperature. DC was determined on the flat surfaces of 6 mm x 2 mm disk-shaped specimens using FTIR. Flexural strength (FS) and modulus (FM) were accessed by three-point bending. Knoop microhardness number (KHN) was measured on fragments of FS specimens. Data were analyzed by one-way ANOVA/Tukey test, Student`s t-test, and regression analysis. Results: DC/top between 6 and 12 J/cm(2) and between 24 and 48 J/cm(2) were not statistically different. No differences between DC/top and bottom were detected. DC/bottom, FM, and KHN/top showed significant differences among all H levels. FS did not vary between 12 and 24 J/cm(2) and between 24 and 48 J/cm(2). KHN/bottom at 3 and 6 J/cm(2) was similar. KHN between top and bottom was different up to 12 J/cm(2). Regression analyses having H as independent variable showed a plateau region above 24 J/cm(2). KHN increased exponentially (top) or linearly (bottom) with DC. FS and FM increased almost linearly with DC/bottom up to 55% conversion. Conclusions: DC and mechanical properties increased with radiant exposure. Variables leveled off at high H levels. (C) 2007 Wiley Periodicals, Inc.

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Science communication. including extension services. plays a key role in achieving sustainable native vegetation management. One of the pivotal aspects of the debate on sustainable vegetation management is the scientific information underpinning policy-making. In recent years. extension services have Shifted their focus from top-down technology transfer to bottom-up participation and empowerment. I here has also been a broadening of communication strategies to recognise the range of stakeholders involved in native vegetation management and to encompass environmental concerns. This paper examines the differences between government approaches to extension services to deliver policy and the need for effective communication to address broader science issues that underpin native vegetation management. The importance of knowing the learning styles of the stakeholders involved in native vegetation management is discussed at a time of increasing reliance on mass communication for information exchange and the importance of personal communication to achieve on-ground sustainable management. Critical factors for effective science-management communication are identified Such as: (i) undertaking scientific studies (research) with community involvement, acceptance and agreed understanding of project objectives (ii) realistic community consultation periods: (iii) matching communication channels with stakeholder needs; (iv) combining scientific with local knowledge in in holistic (biophysical and social) approach to understanding in issued and (v) regional partnerships. These communication factors are considered to be essential to implementing on-ground natural resource management strategics and actions, including those concerned with native vegetation management.

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O presente trabalho teve como objectivos avaliar a influência de diversas grandezas e parâmetros de ensaio no índice de fluidez de termoplásticos e calcular a incerteza associada às determinações. Numa primeira fase, procedeu-se à identificação dos principais parâmetros que influenciam a determinação do índice de fluidez, tendo sido seleccionados a temperatura do plastómetro, o peso de carga, o diâmetro da fieira, o comprimento da medição, o tipo de corte e o número de provetes. Para avaliar a influência destes parâmetros na medição do índice de fluidez, optou-se pela realização de um planeamento de experiências, o qual foi dividido em três etapas. Para o tratamento dos resultados obtidos utilizou-se como ferramenta a análise de variância. Após a completa análise dos desenhos factoriais, verificou-se que os efeitos dos factores temperatura do plastómetro, peso de carga e diâmetro da fieira apresentam um importante significado estatístico na medição do índice de fluidez. Na segunda fase, procedeu-se ao cálculo da incerteza associada às medições. Para tal seleccionou-se um dos métodos mais usuais, referido no Guia para a Expressão da Incerteza da Medição, conhecido como método GUM, e pela utilização da abordagem “passo a passo”. Inicialmente, foi necessária a construção de um modelo matemático para a medição do índice de fluidez que relacionasse os diferentes parâmetros utilizados. Foi estudado o comportamento de cada um dos parâmetros através da utilização de duas funções, recorrendo-se novamente à análise de variância. Através da lei de propagação das incertezas foi possível determinar a incerteza padrão combinada,e após estimativa do número de graus de liberdade, foi possível determinar o valor do coeficiente de expansão. Finalmente determinou-se a incerteza expandida da medição, relativa à determinação do índice de fluidez em volume.

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A Língua Gestual Portuguesa (LGP) foi, em 1997, reconhecida como a língua oficial dos surdos portugueses. Os trabalhos pioneiros de William Stokoe, na década de 60, sustentaram a evidência de que os surdos possuem a sua própria língua, que adquirem de forma natural sempre que expostos a um ambiente linguístico que lhes permita a sua aquisição e desenvolvimento plenos. A LGP é uma língua natural e apresenta uma complexidade estrutural equivalente à das línguas orais, sendo possível distinguir elementos descritivos da mão, tais como a configuração, o local de articulação, o movimento, a orientação e ainda os componentes não-manuais. A LGP desenvolve-se num ―espaço sintáctico‖, espaço em frente do gestuante, onde se organizam as relações morfológicas e sintácticas. Neste artigo, pretendemos descrever e classificar alguns processos de polissemia nominal que detectámos em LGP. Partindo duma abordagem bottom-up, com base num corpus de cem gestos nominais, observámos os processos polissémicos presentes. Tendo como referência um enquadramento teórico-conceptual de cariz cognitivista da noção de polissemia, detectámos processos metonímicos, de denominação através de características estereotípicas de um determinado referente e de possível contacto linguístico entre a Língua Gestual Portuguesa e a Língua Portuguesa Escrita. Também foram encontrados processos de polissemia que parecem assentar numa sinonímia visual e cuja polissemia se reveste de uma identificação sinónima, através de uma imagem comum, entre um referente e outro. Salientaremos ainda que este trabalho se considera exploratório, relativamente, aos processos de polissemia em LGP, sendo nossa intenção continuar a estudar com mais dados este fenómeno.

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Desde o primeiro semestre do ano lectivo 2004-2005, a FCTUNL (Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa) tem vindo a utilizar o Moodle como sistema de gestão da aprendizagem e de trabalho colaborativo, em contextos de uso que vão desde o de apoio a aulas presenciais, cursos a distância, páginas de projectos ou de grupos de alunos. Esta utilização, com impacto nas práticas de um largo número de professores e alunos, teve origem em acontecimentos informais, bottom-up, contribuindo, a par do projecto Universalidade dos Saberes, à criação do Laboratório de e.Learning, com responsabilidades de gestão. Neste artigo, os autores, acompanhando de perto o desenvolvimento da iniciativa, apresentam um breve resumo do percurso do Moodle@FCTUNL, caracterizando-o recorrendo a alguns indicadores quantitativos e qualitativos recolhidos no contexto do trabalho das diversas equipas envolvidas. São partilhadas ainda algumas lições aprendidas pelos mesmos, de particular interesse para equipas de gestão de iniciativas semelhantes, e ideias para futuros possíveis num contexto mais alargado de melhoria do acesso à informação, comunicação, colaboração e ensino-aprendizagem em instituição do ensino superior recorrendo às tecnologias e redes.

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The main goals of the present work are the evaluation of the influence of several variables and test parameters on the melt flow index (MFI) of thermoplastics, and the determination of the uncertainty associated with the measurements. To evaluate the influence of test parameters on the measurement of MFI the design of experiments (DOE) approach has been used. The uncertainty has been calculated using a "bottom-up" approach given in the "Guide to the Expression of the Uncertainty of Measurement" (GUM). Since an analytical expression relating the output response (MFI) with input parameters does not exist, it has been necessary to build mathematical models by adjusting the experimental observations of the response variable in accordance with each input parameter. Subsequently, the determination of the uncertainty associated with the measurement of MFI has been performed by applying the law of propagation of uncertainty to the values of uncertainty of the input parameters. Finally, the activation energy (Ea) of the melt flow at around 200 degrees C and the respective uncertainty have also been determined.