Investigations into extracellular ATP signalling and FB1-induced cell death in Arabidopsis thaliana.

Extracellular ATP (eATP) is an important signalling molecule involved in regulation of plant growth and development, interactions with other organisms and responses to several environmental stimuli. The molecular targets mediating the physiological effects of eATP in plants remain to be identified. The work presented in this thesis focuses on identifying the signalling components that underlie the physiological roles of eATP in plants, with a strong emphasis on cell death control. An Arabidopsis thaliana (Arabidopsis) cell culture system combined with 2-dimensional difference in-gel electrophoresis (2D-DIGE) and mass spectrometry was used to identify proteins differentially expressed following ATP treatment. Twenty four putative cell death proteins were identified using the cell death-inducing toxin Fumonisin B1 (FB1) in combination with an ATP reversal filter. The potential role of these candidates in eATP- regulated cell death was tested using a variety of cell death assays on Arabidopsis T-DNA insertion KO mutants. The mitochondrial ATP synthase β-subunit, AT5G08690, was shown to be a novel cell death gene. The early effects of eATP on global protein and transcript abundance were also investigated. 2D-DiGE identified 53 proteins differentially regulated by ATP and bioinformatic analysis revealed new effects of eATP on general metabolism. Re- examination of a previously acquired DNA chip experiment that used ATP and FB1 treatments identified 10 genes that are differentially expressed within minutes by eATP that can be used as molecular markers. 2D-DiGE proteomics was also used to investigate the specific toxic effects of FB1 on Arabidopsis. A subset of proteins that were specifically regulated by FB1 treatment were tested for a role in FB1-induced cell death using cell death assays on Arabidopsis T-DNA insertion KO mutants. The UDP-glucose pyrophosphorylase, AT3G03250, was identified as a cell death gene responsive to FB1

Equilibria in reflexive Banach lattices with a continuum of agents.

We consider exchange economies with a measure space of agents and for which the commodity space is a separable and reflexive Banach lattice. Under assumptions imposing uniform bounds on marginal rates of substitution, positive results on core-Walras equivalence were established in Rustichini-Yannelis [27] and Podczeck [25]. In this paper we prove that under similar assumptions on marginal rates of substitution, the set of competitive equilibria (and thus the core) is non-empty.Competitive equilibria; Continuum of agents; Reflexive Banach lattice commodity spaces; Uniform properness;

Motivações para o slum tourism induzidas pelo cinema: uma abordagem estrutural

Film tourism encompasses visits to places whose attractiveness is related to audio-visual products (e.g., films, tv-series, soap operas…). A wide range of studies acknowledges those products’ potential to influence destination image, visit motivations, and, consequently, tourist arrivals to the portrayed places. The literature suggests that even films that depict destinations under a bad light can increase motivations to visit them. Such conclusions, strengthened by several real-world cases, imply that films might play a special role in inducing motivations for slum tourism, which is described as tourism to which poverty is part of the attraction. The slum tourism phenomenon has received little academic attention from the perspective of tourism studies, and research on slum tourists’ motivations is particularly scarce. In this context, the present study aims at developing and testing a causal model encompassing slum tourism motivations dimensions and the film elements that act as their determinants, that is, a model of Film-induced slum tourism motivations. To this end, due to the absence of previously validated scales on slum tourism motivations, first, an exploratory, qualitative study was carried out through semi-structured interviews with tourists visiting Rio de Janeiro’s favelas. Such preliminary study also served to adapt existing film tourist motivations theories to the examined context. Insights from the exploratory study helped inform the elaboration of a quantitative survey, which was applied to the same research universe. The collected data was then subjected to Exploratory and Confirmatory Factor Analysis, under the principles of Structural Equations Modelling, in order to verify whether the hypothesised causal relationships were true to the observed reality. Results show that slum tourism motivations are formed by two main dimensions: Learning motivations and Experiential motivations, and that each of those may be influenced by two factors of films determinants: Place & Personality and Performance. The findings expand the academic knowledge on slum tourism motivations, as the study represents a first initiative in structurally addressing them. Exploring the role of films in those motivations is another relevant theoretical contribution. From a managerial perspective, results provide insights that might help destination managers and entrepreneurs in their relationship with the film industry, as well as in the operationalisation and promotion of services.O “film tourism” abrange visitas a locais cuja atratividade está relacionada a produtos audiovisuais (ex: filmes, séries de TV, telenovelas...). Uma ampla gama de estudos reconhece a potencial influência destes produtos na imagem de destinos, nas motivações de visita, e consequentemente, nas chegadas de turistas aos lugares retratados. A literatura sugere que mesmo filmes que retratam destinos de maneira negativa podem amentar as intenções de visita. Tais conclusões, aliadas a alguns casos reais, indicam que filmes podem desempenhar um papel especial na indução de motivações para o slum tourism, que é descrito como o turismo para o qual a pobreza é parte da atração. O fenômeno do slum tourism tem recebido pouca atenção na academia, e investigações sobre as motivações dos slum tourists são particularmente escassas. Neste contexto, o presente estudo visa desenvolver e testar um modelo causal que abranja as dimensões das motivações para o slum tourism e os elementos de filmes que agem como seus determinantes, ou seja, um modelo de Motivações para o slum tourism induzidas por filmes. Para este fim, devido à ausência de escalas previamente validadas para a mensuração de motivações para o slum tourism, primeiramente, um estudo qualitativo exploratório foi realizado por meio de entrevistas semiestruturadas com turistas que que visitavam favelas no Rio de Janeiro. Este estudo preliminar também serviu para adaptar teorias pré-existentes sobre film tourism ao contexto analisado. Conclusões do estudo exploratório auxiliaram na elaboração de um questionário quantitativo, que foi aplicado ao mesmo universo de investigação. Os dados coletados foram submetidos a Análise Fatorial Exploratória e Confirmatória, sob os preceitos da Modelação em Equações Estruturais, de modo a verificar se as relações causais definidas como hipóteses eram fiéis à realidade observada. Os resultados demonstram que as motivações para o slum tourism são formadas por duas dimensões principais: Motivações de aprendizado e Motivações experienciais, e que cada uma destas pode ser influenciada por dois fatores determinantes de filmes: Lugar & Personalidade e Performance. Tais conclusões expandem o conhecimento acadêmico sobre as motivações para o slum tourism, uma vez que o estudo representa uma primeira iniciativa de análise estrutural deste construto. Explorar o papel dos filmes nestas motivações é uma contribuição teórica adicional do trabalho. Do ponto de vista prático, os resultados fornecem importantes descobertas que podem auxiliar gestores de destinos e empreendedores nas suas relações com a indústria cinematográfica, bem como na operacionalização e na promoção de serviços.Programa Doutoral em Turism

Developing a Substation Design Curriculum for Electronics Engineering Technology

Background: The latest technologies have created an increasing demand for the generation, transmission, and distribution of electricity. Substations are a crucial segment of our power grid. Substations are used to step-up voltages for the long-distance transmission of energy and to stepdown voltages for industrial and residential use. The demand for substation design curriculum was discussed at a meeting of the Industrial Advisory Committee (IAC) for EET. Members of the IAC consisted of professionals from Black & Veatch and other companies that work with power systems such as substations and switchgear. The curriculum was developed in close cooperation with Black & Veatch to shape the curriculum with a practical approach. Purpose: This paper describes the development of a substation design curriculum to be used in an Electronics Engineering Technology (EET) program at Pittsburg State University (PSU). Method: In 2019, a PSU faculty participated in a series of NSF sponsored workshops for facilitating the teaching of electric energy (Workshops for Facilitating Faculty to Teach Electric Energy Courses for Combating Climate Change, 2019) since the EET faculty did not have a strong background in power systems. In addition, a graduate assistant with a background in power systems was recruited to create the substation design curriculum. In the same year, a visit to Black & Veatch was conducted where the substation design process was presented to a PSU faculty and the graduate assistant. It was discussed what topics should be included in the curriculum. In 2020, the substation design curriculum was introduced into an existing Electric Power course. The substation curriculum included lectures on the basics of generation, transmission, and distribution; substation components; one-line diagrams; and circuit breaker topologies. The curriculum also consisted of two labs which used the PowerWorld software and an exam. A guest speaker from Black & Veatch concluded the substation curriculum with a presentation of substation design projects. The effectiveness of the substation design curriculum was assessed by analyzing student work on one of the labs and selected questions from the exam on substation design. Results: A rubric was applied to the lab and the average was 1.86 out of 3 points. The percentage of correct answers on selected questions in the exam was 95%.Conclusion: Assessment results for the labs and exam showed that students learned the material and the new curriculum was effective overall. Another benefit of the substation curriculum development was that the graduate student secured an internship at Black & Veatch where he worked in designing substations. In addition, Black & Veatch offered five full scholarships to PSU students in the EET program in 2020-21 academic year and the broadening of students’ knowledge in power systems

Transparencia, Responsabilidad Social y Gobierno Corporativo: el Capital Humano de las empresas

[EN] Companies develop their activity in an environment characterized by knowledge-based economies, with qualified and highly skilled workers. Human Capital is one of the most important intangible resources that companies have to generate sustainable wealth. The main objective of this paper is to analyse the Human Capital information provided by companies in the field of Corporate Social Responsibility and Corporate Governance. Using the methodology of content analysis, this paper analyses the Human Capital disclosure contained in social responsibility reports of Spanish companies belonging to the IBEX 35. In addition, it identifies factors related to Corporate Governance (characteristics of the Board of Directors, and ownership structure of companies) with greatest impact on information provision. Balanced panel data are used to test our hypotheses. Empirical evidence shows a quadratic U-shaped relationship among the size of the board, independence, and the ownership concentration with Human Capital disclosure; and an inverted U-shaped relationship between managers’ ownership of shares and Human Capital disclosure. In addition, it has been found that companies with greater gender diversity on their Board, as well as with greater board activity, tend to disclose more information related to Human Capital.[ES] Las empresas desarrollan su actividad en un entorno caracterizado por economías basadas en el conocimiento, con mano de obra competente y altamente cualificada. El Capital Humano es uno de los recursos de naturaleza intangible más importantes que poseen las empresas para generar riqueza de manera sostenible. El principal objetivo de este trabajo es analizar la información del Capital Humano suministrada por las empresas dentro del ámbito de la Responsabilidad Social Empresarial y del Gobierno Corporativo. Mediante la metodología del análisis de contenido, se analiza la información relativa al Capital Humano contenida en las memorias de responsabilidad social de las empresas españolas pertenecientes al IBEX 35. Además, se determinan aquellos factores relativos al Gobierno Corporativo (características del Consejo de Administración y estructura de la propiedad de la empresa) que mayor incidencia tienen en el suministro de información. Se emplea un panel de datos balanceado para testar nuestras hipótesis. La evidencia empírica obtenida muestra una relación cuadrática en forma de “U” entre el tamaño del consejo, la independencia y la concentración accionarial con la revelación de Capital Humano; y una relación en forma de “U” invertida entre el control accionarial de gestores y la información de Capital Humano. Además, se ha encontrado que aquellas empresas con mayor diversidad de género entre sus consejeros, así como con una mayor actividad del consejo, tienden a revelar más información relativa al Capital Humano.This study was conducted at the Research Centre in Political Science (UID/CPO/00758/2013), University of Minho, and was funded by the Portuguese Foundation for Science and Technology, and by the Portuguese Ministry of Education and Science through national funds

First-pass myocardial perfusion MRI: artifacts and advances

Magnetic resonance imaging of myocardial perfusion during the first-pass of a contrast agent has been proved valuable for the detection of coronary artery disease. During contrast enhancement, transient dark rim artifacts are sometimes visible in the subendocardium, mimicking real perfusion defects and complicating diagnosis. This thesis studied several different mechanisms behind dark rim artifacts with the aim of exploring possible solutions to minimise them and potentially improve the accuracy of perfusion methods. An in-depth review of current myocardial perfusion imaging techniques is presented. This is followed by a comprehensive study of dark rim artifacts, with realistic phantom and numerical simulations, and in vivo measurements. Simulations for the most common perfusion sequences are made, showing that Gibbs, myocardial radial-motion, and frequency-offsets are capable of creating endocardial signal-loss, although dependent on many sequence parameters. Frequency-offsets during first-pass of contrast agentwere measured in vivo; results show negligible intra-voxel signal dephasing, although careful frequency adjustments need to be considered for the b-SSFP and h-EPI sequences. The investigations on dark rim artifacts lead to the development of an ultrafast but robust sequence suitable for first-pass myocardial perfusion imaging, and the assessment of its in vivo performance. The sequence was a multi-slice single-shot spin-echo EPI sequence accelerated by a reduced phase-encode FOV (zonal excitation), and parallel imaging R=2. When tested in clinical volunteers with CA at rest, the sequence yielded a reasonable CNR with a very short acquisition time, although spatial resolution needs to be improved

Métodos de avaliação de necessidade de calagem e sua eficiência na correção dos solos do cerrado

Orientador: Prof. Dra. Bruna RamalhoTrabalho de Conclusão de Curso (Especialização) - Universidade Federal do Paraná, Setor de CIências Agrárias, Curso de Pós-Graduação Fertilidade do Solo e Nutrição de Planta.Resumo: A área agricultável no Brasil em sua grande maioria está localizada no bioma Cerrado, representando cerca de 40% da produção nacional de culturas agrícolas anuais. Dados comprovam que as médias de produtividade das lavouras do Cerrado podem ser até três vezes superiores às do Brasil . Apesar de sua relevância no cenário agrícola, esse bioma ainda apresenta solos com elevada acidez e baixa fertilidade, que refletem diretamente na perda de produtividade das culturas. A operação de calagem surge como uma aliada para garantir que esses solos possam ser cultivados, diminuindo os empecilhos produtivos dos solos de elevada acidez. Existem hoje vários métodos para cálculo da quantidade de corretivo a ser aplicado para correção da acidez do solo, mas informações sobre possíveis diferenças, vantagens e desvantagens entre cada metodologia para os solos desse bioma ainda são escassas. Diante disso, o presente estudo teve por objetivo verificar a eficiência dos diferentes métodos de cálculo de necessidade de calagem para os solos do Cerrado. O trabalho foi desenvolvido através de revisão bibliográfica, com pesquisa e leitura de artigos científicos no período de julho a outubro de 2021. Procedeu-se com a escolha dos artigos através das bases científicas SciELO e Google® Acadêmico, com seleção de artigos nacionais e internacionais de alta relevância. De forma ainda incipiente foi possível verificar que os métodos pH SMP e o de incubação do solo com carbonato de cálcio (CaCO3) mostraram ser os métodos mais eficientes e eficazes em relação a quantidade de corretivo utilizado, bem como, na capacidade de elevar a saturação por bases desses solos (V%). A maior parte dos trabalhos analisados trouxeram informações relevantes a respeito do estudo da calagem para os solos desse bioma, mas vale ressaltar que devido ao número limitado de publicações não foi possível estabelecer respostas concretas em torno desse tema. Pesquisas futuras devem ser conduzidas e investigadas para fechar essa lacuna de conhecimento da eficiência dos métodos de avaliação de necessidade de calagem para os solos do Cerrado brasileiro

Projeto e construção de bancada de ensaios para estudo de sistemas de freio de bicicletas (II)

Trabalho de conclusão de curso (graduação)—Universidade de Brasília, Faculdade UnB Gama, Curso de Engenharia Automotiva, 2016.Na análise de sistemas de freio, é muito importante simular a inércia que o corpo possui quando em movimento, pois esse fator altera completamente a forma como os freios irão se comportar durante a frenagem. Um dinamômetro de inércia simula a inércia que o sistema a ser estudado possui quando em movimento através de um disco de inércia. A bancada aqui dimensionada terá limitações quanto à quantidade de inércia capaz de simular, o intuito aqui é simular um sistema com massa de até 120 kg a uma velocidade máxima de 65 km/h. Foram feitos dois tipos de ensaio, de parada total e de drenagens cíclicas. Em cada ensaio, foram usados dois valores de carga de frenagem, 80N e 40N. A fim de saber quais eram os materiais que seriam usados nos ensaios, foi feito um estudo sobre a composição química de cada um deles e sobre suas respectivas microestruturas. Os ensaios de parada total sofreram grandes variações da força de atrito inicial e final, tanto nos ensaios com 80N quanto nos com 40N de carga de frenagem. Isso ocorreu devido à deposição de material das pastilhas na superfície do disco de freio. Os valores de perda de massa durante esses ensaios foram medidos e tiveram comportamento bastante linear. A variação da temperatura máxima foi extremamente parecida nos ensaios de 80N e 40N. A rugosidade da superfície variou de forma linear, porém o disco de freio foi alisado e as pastilhas sofreram aumento da rugosidade superficial. Quando realizados os ensaios de frenagem cíclica, a força de atrito se comportou de forma bastante homogênea, tendo o mesmo comportamento em todos os ensaios, com diferenças apenas entre os ensaios com cargas de frenagem distintas. O desgaste dos discos e das pastilhas também foi contínuo e sem grandes variações inesperadas. A rugosidade superficial nesses ensaios sofreu aumento em todos os componentes, e a variação deste fator foi muito similar em todos os ensaios, fator que justifica a forma como a força de atrito se comportou. O aspecto superficial dos discos de freio após cada tipo de ensaio foi bastante distinto, nos ensaios de parada total a superfície mostrava grandes marcas de frenagem, bastante evidentes e cheias de material aderido. Nos ensaios de frenagem cíclica, as marcas de frenagem eram menos evidentes, porém a quantidade de material na superfície também era bem elevada e perceptível.In brake system analysis is very important to consider the inertia the moving body has, because this factor can modify completely the way the brake system will behave during braking. An inertial dynamometer simulates the inertia of the moving body upon study by spinning an inertial disc. The bench here designed will have some restrictions on the quantity of inertia it will be able to produce. The intention is to simulate a system with maximum weight of 120 kg and a maximum speed of 65 km/h. Two types of analysis were done, complete stop ant cycling braking. In each analysis, two values of brake load, 80N and 40N. Looking forward to know what kind of material were used, a research about their chemical composition and microstructure took place. In the total stop analysis the friction force suffered an huge change from the initial to the final value, in the analysis with 80N of load such as in the analysis with 40N of load. It happened because of the material deposition in the disc brake surface. The weight loss during the analysis were measured and it’s behaviour were linear. The maximum temperature variation were extremely similar with loads of 80N and 40N. The superficial rough varies linearly, but the brake discs were smoothed and the brake pads rugh were increased. When the cyclic braking analysis took place, the behaviour of the friction force was very homogeneous, showing the same behaviour in all the analysis, with differences only when the load was changed. The weight losses were continuous and without big unexpected changes. The superficial rough in this analysis was increased in all the components, the behaviour of this factor was very similar through all the analysis, it justifies the friction force behaviour. The superficial aspect on the disc brakes after each type of analysis were very different, in the total stop analysis the surface showed huge braking marks, very easy to see and full of adhered material. In the cycling brake analysis, the braking marks weren’t so easy to see, but the amount of adhered material was very high and noticeable

Harsh default penalties lead to Ponzi schemes: a counterexample

Preprint dated October 12, 2011. Final version published by Elsevier; available online at http://www.sciencedirect.com/Pascoa and Seghir (2009) presented two examples to show that in the presence of utility penalties for default, collateral requirements do not always eliminate the occurrence of Ponzi schemes and equilibria may fail to exist. We provide a counterexample to their claim by showing that no trade is a competitive equilibrium in the examples they consider