1,548 research outputs found
Full Length Research Paper Curcumin induces cleavage of -catenin by activation of capases and downregulates the β-catenin/Tcf signaling pathway in HT-29 cells
β-Catenin/Tcf-4 signaling pathway plays important roles in colorectal tumorigenesis. RT-PCR, western blotting and immunoprecipitation were used to study the effects of curcumin on β-catenin/Tcf-4 signaling pathway in HT-29 cells. Treatment of curcumin could induce cleavage of β-catenin and the cleavage could be inhibited by caspase inhibitors. The association of β-catenin with Tcf-4 in nucleus could be inhibited by curcumin. The expression of c-myc and cyclinD1 was downregulated by curcumin, which could not be blocked by Z-DEVD-FMK. The results showed curcumin could induce thecleavage of β-catenin by activition of caspases and downregulate the activity of β-catenin/Tcf signaling pathway independent of the caspases in HT-29 cells
Resistance to stem rust race TTKS in wheat relative Haynaldia villosa
Tese de doutoramento em Território, Risco e PolÃticas Públicas, apresentada ao Instituto de Investigação Interdisciplinar da Universidade de CoimbraFor several decades critical infrastructure management belonged to engineering
domains; however a new paradigm has emerged - socio-technical paradigm -
infrastructures are critical because they have value for society and for a culture. Thus,
critical infrastructure operate not only according to technical specifications but also
according to constraints imposed by the social environment. The problem is how to
integrate in the same model the linkages between infrastructure and social systems. The
main goal of this thesis is to propose a new model the Structural Functional Risk Model –
SFRM- a model that identifies the roads more vulnerable to interruptions, based on an
integrated approach of the structural and functional component of the road network- a
critical infrastructure responsible for connecting people, assets and services separated in
space. The model is applied to real road network in a multiscalar perspective, the
regional context and the municipal context. The case studies are the Central Region of
Portugal and Coimbra, a municipality located in this Region. The system used as example
focus the road network as element of connection and access between the parishes and
the nearest Hospital – a critical infrastructure of the health sector.
The methodological approach is composed by three main phases: firstly, the road
network is assessed in a structural perspective based on the application of a new
approach of the biclustering technique; the following phase is focused on the evaluation
of the road network in a functional perspective based on a modified gravity model; the
last phase is focused on the integration of structural and functional perspective, which
resulted the SFRM. Scenario- based approaches are also relevant in this work, focusing
questions such: what can happen? If it does happen, what are the consequences? A
scenario-based approach can be a useful support to a more informed, strategic action.
Thus, through the work there will be simulated and analyzed road interruption
scenarios.
The results confirmed the importance of an integrated approach of the structural and
functional components. In the assessment of the road network structural component
the results pointed that the Biclusters with highest connectivity are mainly located in the
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areas economically most dynamic, such the Coastal zone, and the Biclusters with lowest
connectivity are mainly located in areas less dynamic, such Beira Transmontana. So,
even when the analysis is focused on a network transformed into nodes and edges it is
possible to identify relations with the territorial dynamics. The results of the road
network functional component assessment point to a significant resources
concentration in Coimbra municipality; in the regional context identified significant
accessibility gaps across geographical areas and population groups; even in a normal
scenario there are significant disparities in terms of accessibility to health care, which
can get worse in a road network interruption scenario. From the integration of the
structural and functional component of the road network resulted the SFRM, which is a
step forward; quantifying the share of accountability of each of the components in the
road level of vulnerability. The results demonstrate that territorial constraints play a
fundamental role in critical infrastructure management; the strategies set in this domain
should take into account the specificities of each territory and population
characteristics.
This thesis can be seen as step forward in the consolidation of the socio-technical
paradigm as well as a tool for the definition of efficient of prevention measures and the
definition of strategies aiming quick recovery of the system in case of a disruptive event.Durante várias décadas a gestão das infra-estruturas crÃticas pertenceu ao domÃnio da
engenharia; contudo surgiu um novo paradigma – o paradigma socio-técnico – as infraestruturas
são crÃticas pelo valor que representam para a sociedade e para a cultura.
Neste sentido, o funcionamento das infra-estruturas crÃticas depende não só de
especificidades técnicas, mas também é condicionado pelo meio social. O problema
reside em saber como integrar no mesmo modelo as ligações existentes entre as infraestruturas
e os sistemas sociais. O principal objetivo deste trabalho é propor um novo
modelo - Modelo de Risco Estrutural e Funcional – MREF- que identifica as vias mais
vulneráveis a interrupções, numa abordagem integrada da componente estrutural e
funcional da rede viária – uma infra-estrutura crÃtica que tem como função ligar pessoas,
bens e serviços separados no espaço. O MRFE é aplicado a uma rede viária real numa
perspetiva multiescalar, os casos de estudo são a Região Centro de Portugal e Coimbra,
um municÃpio localizado nesta Região. O sistema de análise, usado como exemplo, focase
na rede viária como elemento de ligação e acesso entre as freguesias e os Hospitais –
importantes infra-estruturas crÃticas do sector da saúde.
A metodologia usada neste trabalho é constituÃda por três fases: numa primeira fase a
rede viária é avaliada sob o ponto de vista estrutural com base numa nova abordagem
da técnica de biclustering; a fase seguinte foca-se na avaliação da rede viária sob o
ponto de vista funcional com base num modelo gravitacional adaptado aos objetivos do
presente trabalho; a última fase foca-se na integração da avaliação estrutural com a
funcional da qual resulta o MRFE. As abordagens com base em cenários também
assumem relevância neste trabalho, focando questões como: O que pode acontecer?
Caso aconteça, quais são as consequências? Os resultados desta abordagem contribuem
para ação mais informada e estratégica. Neste sentido, ao longo do trabalho serão
apresentados e avaliados vários cenários de interrupção de vias.
Os resultados demonstram a importância de uma abordagem integrada da componente
funcional e da estrutural. Aquando da avaliação da rede viária sob o ponto de vista
estrutural os resultados indicaram que os biclusters com maior nÃvel de conectividade se
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encontram essencialmente localizados nas áreas economicamente mais dinâmicas –
como a zona costeira, enquanto os biclusters com menor nÃvel de conectividade se
encontram essencialmente localizados nas áreas economicamente mais deprimidas –
como a Beira Transmontana. Conclui-se que mesmo quando a análise se foca na rede
viária enquanto conjunto de nós e ligações é possÃvel identificar relações com a dinâmica
territorial. Os resultados da avaliação da rede viária sob o ponto de vista funcional
indicam uma significativa polarização de recursos no municÃpio de Coimbra, no contexto
regional foram identificadas expressivas diferenças em termos de áreas geográficas e
grupos populacionais; estas significativas disparidades poderão ser agravadas num
cenário de interrupção de vias. O MREF resulta de uma abordagem integrada das
componentes estruturais e funcionais da rede viária, um modelo que pode ser visto
como um passo em frente uma vez que são definidas e quantificadas as variáveis que
influenciam a vulnerabilidade da rede viária. Os resultados demonstram que as
condicionantes territoriais devem constituir uma componente fundamental na gestão
das infra-estruturas crÃticas; as estratégias definidas neste âmbito devem ter em atenção
as especificidades do território e as caracterÃsticas da população.
O presente trabalho pode ser visto como contributo para a consolidação do paradigma
sociotécnico assim como um instrumento para a definição de medidas de prevenção
eficientes e definição de estratégias que tenham em vista o rápido restabelecimento do
funcionamento do sistema num cenário disruptivo.Fundação para a Ciência e Tecnologia - SFRH/BD/70952/201
Chemical Composition, Fiber Morphology, and Pulping of P. Bolleana Lauche
The chemical composition and fiber morphology of the P. bolleana Lauche was assessed for its suitability for pulping and papermaking. The P. bolleana Lauche used in this study contained a low amount of lignin, but higher quantities of cellulose and hemicelluloses. It was found that morphological indices of P. bolleana Lauche were adequate for pulping and papermaking. The pulping of this wood was carried out using conventional kraft and soda pulping process under varying conditions. The results indicated that at higher sulfidity (24%-32%) with lower EA (14-16%), higher yields, and viscosity of pulping were obtained with an acceptable kappa number. Kraft pulp of P. bolleana Lauche obtained at given conditions (EA 14-16%; sulfidity 24-32%) provided paper sheets with greater tensile strength, burst index and tear index, at the same beating degree
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Memristor-Based Hierarchical Attention Network for Multimodal Affective Computing in Mental Health Monitoring
10.13039/501100001809-National Natural Science Foundation of China (Grant Number: 62001149 and U1909201); 10.13039/501100004731-Natural Science Foundation of Zhejiang Province (Grant Number: LQ21F010009)
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A Flexible Memristor Model with Electronic Resistive Switching Memory Behavior and its Application in Spiking Neural Network
National Natural Science Foundation of China under Grant U1909201, Grant 62001149; Natural Science Foundation of Zhejiang Province under Grant LQ21F010009
Physical mapping integrated with syntenic analysis to characterize the gene space of the long arm of wheat chromosome 1A
Background: Bread wheat (Triticum aestivum L.) is one of the most important crops worldwide and its production faces pressing challenges, the solution of which demands genome information. However, the large, highly repetitive hexaploid wheat genome has been considered intractable to standard sequencing approaches. Therefore the International Wheat Genome Sequencing Consortium (IWGSC) proposes to map and sequence the genome on a chromosome-by-chromosome basis.
Methodology/Principal Findings: We have constructed a physical map of the long arm of bread wheat chromosome 1A using chromosome-specific BAC libraries by High Information Content Fingerprinting (HICF). Two alternative methods (FPC and LTC) were used to assemble the fingerprints into a high-resolution physical map of the chromosome arm. A total of 365 molecular markers were added to the map, in addition to 1122 putative unique transcripts that were identified by microarray hybridization. The final map consists of 1180 FPC based or 583 LTC based contigs. Conclusions/Significance: The physical map presented here marks an important step forward in mapping of hexaploid bread wheat. The map is orders of magnitude more detailed than previously available maps of this chromosome, and the assignment of over a thousand putative expressed gene sequences to specific map locations will greatly assist future functional studies. This map will be an essential tool for future sequencing of and positional cloning within chromosome 1A
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