859 resultados para GATED SPECT


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The importance of ion channels in the hallmarks of many cancers is increasingly recognised. This article reviews current knowledge of the expression of members of the voltage-gated calcium channel family (CaV) in cancer at the gene and protein level and discusses their potential functional roles. The ten members of the CaV channel family are classified according to expression of their pore-forming α-subunit; moreover, co-expression of accessory α2δ, β and γ confers a spectrum of biophysical characteristics including voltage dependence of activation and inactivation, current amplitude and activation/inactivation kinetics. CaV channels have traditionally been studied in excitable cells including neurones, smooth muscle, skeletal muscle and cardiac cells, and drugs targeting the channels are used in the treatment of hypertension and epilepsy. There is emerging evidence that several CaV channels are differentially expressed in cancer cells compared to their normal counterparts. Interestingly, a number of CaV channels also have non-canonical functions and are involved in transcriptional regulation of the expression of other proteins including potassium channels. Pharmacological studies show that CaV canonical function contributes to the fundamental biology of proliferation, cell-cycle progression and apoptosis. This raises the intriguing possibility that calcium channel blockers, approved for the treatment of other conditions, could be repurposed to treat particular cancers. Further research will reveal the full extent of both the canonical and non-canonical functions of CaV channels in cancer and whether calcium channel blockers are beneficial in cancer treatment.

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We apply the formalism of quantum estimation theory to extract information about potential collapse mechanisms of the continuous spontaneous localisation (CSL) form.
In order to estimate the strength with which the field responsible for the CSL mechanism couples to massive systems, we consider the optomechanical interaction
between a mechanical resonator and a cavity field. Our estimation strategy passes through the probing of either the state of the oscillator or that of the electromagnetic field that drives its motion. In particular, we concentrate on all-optical measurements, such as homodyne and heterodyne measurements.
We also compare the performances of such strategies with those of a spin-assisted optomechanical system, where the estimation of the CSL parameter is performed
through time-gated spin-like measurements.

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The research aimed to understand the challenges for the implementation of the proposed integration between the Civil Police and the Military Police in Rio Grande do Norte to the proposals of the SUSP. This study aimed to explore the gap with regard to the deepening of the possible causes that may hinder the implementation of integrated working between the police in public security, through a specific analysis on the state of Rio Grande do Norte. Was based on a theoretical framework that includes policies: general concepts, the steps of a public policy, the implementation stage , public security : conceptual definitions, policies on security in Brazil, the structure of public security in Brazil and systems police, Military Police x Civil Police: Roles and conflicts , integrating public security: the challenges to be overcome, the Unified public Safety (SUSP) and the main difficulties in the integration of the police. Being classified as to the purposes as an exploratory research on how to approach ranks as qualitative. The research unit was the Center for Integrated Operations Public Safety (CIOSP) through three subjects who were the chief CIOSP, the representative of the military police acting with the CIOSP, and representative civil police also active with the CIOSP. These subjects were chosen because of the understanding that individuals occupying senior positions would have more ability to respond to questions that guide the research problem. Data were collected through a set of interviews, qualitative data analysis was performed based content analysis, based on the definition of categories of analysis, gated time cross. With the results, it was revealed that the main problems of integration between the state police are treatment protocols, lack of political will and lack of infrastructure. The relationship between the Military Police and Civil Police in Rio Grande do Norte has differing cultural aspect, but can be considered as good value, professionalism and integrated operations. The implementation of CIOSP-RN followed the characteristics of the top-down model, the main difficulties in implementing the proposals of the SUSP, lack of own resources, the lack of standardization in public safety and the lack of professional training of public safety. It was concluded that with respect to the challenges to the implementation of the proposed integration between the Civil Police and the Military Police in Rio Grande do Norte to the proposals of the SUSP, the actions follow the characteristics of the top-down model, with no autonomy of administrators public to say in decisions, which restricts the view of the public safety of the state

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Atualmente, no estudo do comportamento de descarregadores de cheias por orifício, é necessário conhecer as pressões ao longo do descarregador, para várias alturas de água na albufeira. Este tipo de estudos tem sido usualmente realizado recorrendo a ensaios experimentais. No entanto, a utilização de modelos numéricos para a simulação do escoamento em estruturas hidráulicas encontra-se numa fase emergente. Neste sentido, a presente dissertação pretende apresentar um estudo numérico relativo ao escoamento em descarregadores de cheias por orifício. Por forma a efetuar o estudo numérico, foi utlizado o programa comercial de CFD FLOW-3D®, reproduzindo um modelo reduzido construído no Laboratório Nacional de Engenharia Civil (LNEC) correspondente a um descarregador por orifício. Para a realização das simulações numéricas foi necessário definir o objeto de estudo, a malha de cálculo, as condições de fronteira e as propriedades do fluido e objeto de modo a reproduzir as situações ensaiadas experimentalmente no LNEC. A proximidade dos resultados experimentais e numéricos para vários níveis de água na albufeira permitiu validar o modelo numérico para este tipo de escoamentos no interior do orifício.

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Incidental findings on low-dose CT images obtained during hybrid imaging are an increasing phenomenon as CT technology advances. Understanding the diagnostic value of incidental findings along with the technical limitations is important when reporting image results and recommending follow-up, which may result in an additional radiation dose from further diagnostic imaging and an increase in patient anxiety. This study assessed lesions incidentally detected on CT images acquired for attenuation correction on two SPECT/CT systems. Methods: An anthropomorphic chest phantom containing simulated lesions of varying size and density was imaged on an Infinia Hawkeye 4 and a Symbia T6 using the low-dose CT settings applied for attenuation correction acquisitions in myocardial perfusion imaging. Twenty-two interpreters assessed 46 images from each SPECT/CT system (15 normal images and 31 abnormal images; 41 lesions). Data were evaluated using a jackknife alternative free-response receiver-operating-characteristic analysis (JAFROC). Results: JAFROC analysis showed a significant difference (P < 0.0001) in lesion detection, with the figures of merit being 0.599 (95% confidence interval, 0.568, 0.631) and 0.810 (95% confidence interval, 0.781, 0.839) for the Infinia Hawkeye 4 and Symbia T6, respectively. Lesion detection on the Infinia Hawkeye 4 was generally limited to larger, higher-density lesions. The Symbia T6 allowed improved detection rates for midsized lesions and some lower-density lesions. However, interpreters struggled to detect small (5 mm) lesions on both image sets, irrespective of density. Conclusion: Lesion detection is more reliable on low-dose CT images from the Symbia T6 than from the Infinia Hawkeye 4. This phantom-based study gives an indication of potential lesion detection in the clinical context as shown by two commonly used SPECT/CT systems, which may assist the clinician in determining whether further diagnostic imaging is justified.

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The present work analyzes the fast evolution of gated communities in Natal-RN´s urban space. Characterized by the occupation of large areas, providing private security and utilities, this kind of real estate use arises a long list of questions and issues from society and scholars, due to privatization of urban space, bending of law constraints and the lack of an integrated planning of the cities where they are built. The reasons for its fast growth in Brazil s urban areas are analyzed, considering the impact on formal urban planning and municipal services and on the identification of urbanistic, architectural pattern and constraints, as well as legal, social and economic issues. This study is based on the detailed analysis of the first three units of gated communities built in the urban space in Natal, between 1995 and 2003, including their evolution throughout time and the specific social and economic reasons for its present widespread adoption in Brazilian real estate market and, particulary, in our city. The main objective of this piece of work is to answer the why s and how s these phenomena evolved, setting a basis for the definition of adequate public policies and regulation of this kind of urban land use

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Single-walled carbon nanotubes (SWNTs) have been studied as a prominent class of high performance electronic materials for next generation electronics. Their geometry dependent electronic structure, ballistic transport and low power dissipation due to quasi one dimensional transport, and their capability of carrying high current densities are some of the main reasons for the optimistic expectations on SWNTs. However, device applications of individual SWNTs have been hindered by uncontrolled variations in characteristics and lack of scalable methods to integrate SWNTs into electronic devices. One relatively new direction in SWNT electronics, which avoids these issues, is using arrays of SWNTs, where the ensemble average may provide uniformity from device to device, and this new breed of electronic material can be integrated into electronic devices in a scalable fashion. This dissertation describes (1) methods for characterization of SWNT arrays, (2) how the electrical transport in these two-dimensional arrays depend on length scales and spatial anisotropy, (3) the interaction of aligned SWNTs with the underlying substrate, and (4) methods for scalable integration of SWNT arrays into electronic devices. The electrical characterization of SWNT arrays have been realized by polymer electrolyte-gated SWNT thin film transistors (TFTs). Polymer electrolyte-gating addresses many technical difficulties inherent to electrical characterization by gating through oxide-dielectrics. Having shown polymer electrolyte-gating can be successfully applied on SWNT arrays, we have studied the length scaling dependence of electrical transport in SWNT arrays. Ultrathin films formed by sub-monolayer surface coverage of SWNT arrays are very interesting systems in terms of the physics of two-dimensional electronic transport. We have observed that they behave qualitatively different than the classical conducting films, which obey the Ohm’s law. The resistance of an ultrathin film of SWNT arrays is indeed non-linear with the length of the film, across which the transport occurs. More interestingly, a transition between conducting and insulating states is observed at a critical surface coverage, which is called percolation limit. The surface coverage of conducting SWNTs can be manipulated by turning on and off the semiconductors in the SWNT array, leading to the operation principle of SWNT TFTs. The percolation limit depends also on the length and the spatial orientation of SWNTs. We have also observed that the percolation limit increases abruptly for aligned arrays of SWNTs, which are grown on single crystal quartz substrates. In this dissertation, we also compare our experimental results with a two-dimensional stick network model, which gives a good qualitative picture of the electrical transport in SWNT arrays in terms of surface coverage, length scaling, and spatial orientation, and briefly discuss the validity of this model. However, the electronic properties of SWNT arrays are not only determined by geometrical arguments. The contact resistances at the nanotube-nanotube and nanotube-electrode (bulk metal) interfaces, and interactions with the local chemical groups and the underlying substrates are among other issues related to the electronic transport in SWNT arrays. Different aspects of these factors have been studied in detail by many groups. In fact, I have also included a brief discussion about electron injection onto semiconducting SWNTs by polymer dopants. On the other hand, we have compared the substrate-SWNT interactions for isotropic (in two dimensions) arrays of SWNTs grown on Si/SiO2 substrates and horizontally (on substrate) aligned arrays of SWNTs grown on single crystal quartz substrates. The anisotropic interactions associated with the quartz lattice between quartz and SWNTs that allow near perfect horizontal alignment on substrate along a particular crystallographic direction is examined by Raman spectroscopy, and shown to lead to uniaxial compressive strain in as-grown SWNTs on single crystal quartz. This is the first experimental demonstration of the hard-to-achieve uniaxial compression of SWNTs. Temperature dependence of Raman G-band spectra along the length of individual nanotubes reveals that the compressive strain is non-uniform and can be larger than 1% locally at room temperature. Effects of device fabrication steps on the non-uniform strain are also examined and implications on electrical performance are discussed. Based on our findings, there are discussions about device performances and designs included in this dissertation. The channel length dependences of device mobilities and on/off ratios are included for SWNT TFTs. Time response of polymer-electrolyte gated SWNT TFTs has been measured to be ~300 Hz, and a proof-of-concept logic inverter has been fabricated by using polymer electrolyte gated SWNT TFTs for macroelectronic applications. Finally, I dedicated a chapter on scalable device designs based on aligned arrays of SWNTs, including a design for SWNT memory devices.

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This research examines the process of placemaking in LeDroit Park, a residential Washington, DC, neighborhood with a historic district at its core. Unpacking the entwined physical and social evolution of the small community within the context of the Nation’s Capital, this analysis provides insight into the role of urban design and development as well as historic designation on shaping collective identity. Initially planned and designed in 1873 as a gated suburb just beyond the formal L’Enfant-designed city boundary, LeDroit Park was intended as a retreat for middle and upper-class European Americans from the growing density and social diversity of the city. With a mixture of large romantic revival mansions and smaller frame cottages set on grassy plots evocative of an idealized rural village, the physical design was intentionally inwardly-focused. This feeling of refuge was underscored with a physical fence that surrounded the development, intended to prevent African Americans from nearby Howard University and the surrounding neighborhood, from using the community’s private streets to access the City of Washington. Within two decades of its founding, LeDroit Park was incorporated into the District of Columbia, the surrounding fence was demolished, and the neighborhood was racially integrated. Due to increasingly stringent segregation laws and customs in the city, this period of integration lasted less than twenty years, and LeDroit Park developed into an elite African American enclave, using the urban design as a bulwark against the indignities of a segregated city. Throughout the 20th century housing infill and construction increased density, yet the neighborhood never lost the feeling of security derived from the neighborhood plan. Highlighting the architecture and street design, neighbors successfully received historic district designation in 1974 in order to halt campus expansion. After a stalemate that lasted two decades, the neighborhood began another period of transformation, both racial and socio-economic, catalyzed by a multi-pronged investment program led by Howard University. Through interviews with long-term and new community members, this investigation asserts that the 140-year development history, including recent physical interventions, is integral to placemaking, shaping the material character as well as the social identity of residents.

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Dengue fever is one of the most important mosquito-borne diseases worldwide and is caused by infection with dengue virus (DENV). The disease is endemic in tropical and sub-tropical regions and has increased remarkably in the last few decades. At present, there is no antiviral or approved vaccine against the virus. Treatment of dengue patients is usually supportive, through oral or intravenous rehydration, or by blood transfusion for more severe dengue cases. Infection of DENV in humans and mosquitoes involves a complex interplay between the virus and host factors. This results in regulation of numerous intracellular processes, such as signal transduction and gene transcription which leads to progression of disease. To understand the mechanisms underlying the disease, the study of virus and host factors is therefore essential and could lead to the identification of human proteins modulating an essential step in the virus life cycle. Knowledge of these human proteins could lead to the discovery of potential new drug targets and disease control strategies in the future. Recent advances of high throughput screening technologies have provided researchers with molecular tools to carry out investigations on a large scale. Several studies have focused on determination of the host factors during DENV infection in human and mosquito cells. For instance, a genome-wide RNA interference (RNAi) screen has identified host factors that potentially play an important role in both DENV and West Nile virus replication (Krishnan et al. 2008). In the present study, a high-throughput yeast two-hybrid screen has been utilised in order to identify human factors interacting with DENV non-structural proteins. From the screen, 94 potential human interactors were identified. These include proteins involved in immune signalling regulation, potassium voltage-gated channels, transcriptional regulators, protein transporters and endoplasmic reticulum-associated proteins. Validation of fifteen of these human interactions revealed twelve of them strongly interacted with DENV proteins. Two proteins of particular interest were selected for further investigations of functional biological systems at the molecular level. These proteins, including a nuclear-associated protein BANP and a voltage-gated potassium channel Kv1.3, both have been identified through interaction with the DENV NS2A. BANP is known to be involved in NF-kB immune signalling pathway, whereas, Kv1.3 is known to play an important role in regulating passive flow of potassium ions upon changes in the cell transmembrane potential. This study also initiated a construction of an Aedes aegypti cDNA library for use with DENV proteins in Y2H screen. However, several issues were encountered during the study which made the library unsuitable for protein interaction analysis. In parallel, innate immune signalling was also optimised for downstream analysis. Overall, the work presented in this thesis, in particular the Y2H screen provides a number of human factors potentially targeted by DENV during infection. Nonetheless, more work is required to be done in order to validate these proteins and determine their functional properties, as well as testing them with infectious DENV to establish a biological significance. In the long term, data from this study will be useful for investigating potential human factors for development of antiviral strategies against dengue.

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Glioblastoma (GBM) is a highly aggressive and fatal brain cancer that is associated with a number of diagnostic, therapeutic, and treatment monitoring challenges. At the time of writing, inhibition of a protein called poly (ADP-ribose) polymerase-1 (PARP-1) in combination with chemotherapy was being investigated as a novel approach for the treatment of these tumours. However, human studies have encountered toxicity problems due to sub-optimal PARP-1 inhibitor and chemotherapeutic dosing regiments. Nuclear imaging of PARP-1 could help to address these issues and provide additional insight into potential PARP-1 inhibitor resistance mechanisms. Furthermore, nuclear imaging of the translocator protein (TSPO) could be used to improve GBM diagnosis, pre-surgical planning, and treatment monitoring as TSPO is overexpressed by GBM lesions in good contrast to surrounding brain tissue. To date, relatively few nuclear imaging radiotracers have been discovered for PARP-1. On the other hand, numerous tracers exist for TSPO many of which have been investigated in humans. However, these TSPO radiotracers suffer from either poor pharmacokinetic properties or high sensitivity to human TSPO polymorphism that can affect their binding to TSPO. Bearing in mind the above and the high attrition rates associated with advancement of radiotracers to the clinic, there is a need for novel radiotracers that can be used to image PARP-1 and TSPO. This thesis reports the pre-clinical discovery programme that led to the identification of two potent PARP-1 inhibitors, 4 and 17, that were successfully radiolabelled to generate the potential SPECT and PET imaging agents [123I]-4 and [18F]-17 respectively. Evaluation of these radiotracers in mice bearing subcutaneous human GBM xenografts using ex vivo biodistribution techniques revealed that the agents were retained in tumour tissue due to specific PARP-1 binding. This thesis also describes the pre-clinical in vivo evaluation of [18F]-AB5186, which is a novel radiotracer discovered previously within the research group with potential for PET imaging of TSPO. Using ex vivo autoradiography and PET imaging the agent was revealed to accumulate in intracranial human GBM tumour xenografts in good contrast to surrounding brain tissue, which was due to specific binding to TSPO. The in vivo data for all three radiolabelled compounds warrants further pre-clinical investigations with potential for clinical advancement in mind.

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Developments in theory and experiment have raised the prospect of an electronic technology based on the discrete nature of electron tunnelling through a potential barrier. This thesis deals with novel design and analysis tools developed to study such systems. Possible devices include those constructed from ultrasmall normal tunnelling junctions. These exhibit charging effects including the Coulomb blockade and correlated electron tunnelling. They allow transistor-like control of the transfer of single carriers, and present the prospect of digital systems operating at the information theoretic limit. As such, they are often referred to as single electronic devices. Single electronic devices exhibit self quantising logic and good structural tolerance. Their speed, immunity to thermal noise, and operating voltage all scale beneficially with junction capacitance. For ultrasmall junctions the possibility of room temperature operation at sub picosecond timescales seems feasible. However, they are sensitive to external charge; whether from trapping-detrapping events, externally gated potentials, or system cross-talk. Quantum effects such as charge macroscopic quantum tunnelling may degrade performance. Finally, any practical system will be complex and spatially extended (amplifying the above problems), and prone to fabrication imperfection. This summarises why new design and analysis tools are required. Simulation tools are developed, concentrating on the basic building blocks of single electronic systems; the tunnelling junction array and gated turnstile device. Three main points are considered: the best method of estimating capacitance values from physical system geometry; the mathematical model which should represent electron tunnelling based on this data; application of this model to the investigation of single electronic systems. (DXN004909)

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Problemática em estudo: A frequente ocorrência da ausência de estenose coronária relevante no procedimento de Hemodinâmica/Tomografia Axial Computorizada (TAC) coronária, em pacientes nos quais fora detectada a presença de isquemia na Cintigrafia de Perfusão Miocárdica (CPM). Objectivos: Particularizar o papel das técnicas nucleares convencionais, nomeadamente a Tomografia Computorizada por Emissão de Fotão Único (SPECT), no estudo da viabilidade do tecido miocárdico. Avaliar pacientes nos quais foi identificada a presença de isquemia no exame de SPECT cardíaco mas procedimento de Hemodinâmica/TAC coronária normal ou sem estenose relevante, para pesquisa de possíveis falsos-positivos da CPM. Elaborar um estudo populacional, que permita demonstrar a relação entre a incidência de falsos positivos e factores como o género, a idade, factores de risco (hipertensão arterial, diabetes, hipercolesterolemia e tabagismo) e as alterações mais relevantes nos exames complementares de diagnóstico aos quais foram sujeitos. Definir o prognóstico para estes doentes, comparando-os com pacientes com CPM normal. Metodologia: Contextualização bibliográfica do tema, seguida do levantamento de todas as CPM realizadas no 1º semestre de 2012, em doentes seguidos no Centro Hospitalar Cova da Beira (CHCB), e a identificação daquelas com resultados positivos para a presença de isquemia; comparação com os exames de Hemodinâmica e TAC coronária para a pesquisa de falsos-positivos. Recolha de informação relativa à idade, género, factores de risco, eventos cardíacos que tenham tido lugar até um ano após a realização da CPM, e outros exames efectuados por estes pacientes, tais como o Electrocardiograma (ECG) e o Ecocardiograma. Análise estatística descritiva e inferencial dos resultados obtidos de forma a estabelecer/descartar a existência de relações entre as variáveis em estudo. Comparação dos resultados obtidos em relação a um grupo de controlo, integrado por pacientes com CPM normal realizada no mesmo período, com a elaboração de uma proposta de prognóstico para os casos falsos-positivos. Material: A recolha de dados foi baseada na Tabela de Recolha de Dados, enviada em Anexo. Os processos consultados eram processos de natureza electrónica, acessíveis por computador, através do programa Sclínico, no Gabinete de Biblioteca e Documentação do CHCB. A análise estatística dos resultados obtidos foi realizada com recurso ao programa IBM SPSS Statistics 21. Para a caracterização da amostra recorreu-se à estatística descritiva, sendo analisadas as medidas de tendência central e de dispersão (média e desvio padrão), bem como a distribuição de frequências, quer absolutas, quer relativas. Seguiu-se a inferência estatística, com o intuito de verificar possíveis relações existentes entre as variáveis. Para isso foram utilizados testes paramétricos ou não paramétricos, adequados à amostra e hipóteses em estudo, nomeadamente o teste t de Student, com recurso ainda ao teste Kolmogorov-Smirnov com correcção de significância de Lilliefors e do teste de Levene. Foi ainda utilizado o teste Qui-Quadrado e, na ausência dos pressupostos para sua aplicação, recorreu-se ao teste exacto de Fisher. Resultados/Discussão: Foi estudada uma amostra total de 144 casos de pacientes submetidos a CPM. Desta amostra foram particularizados 2 grupos; um grupo de controlo (n=81) e um grupo de falsos positivos (n=13) e analisadas as principais diferenças entre estes 2 grupos, tendo em conta as variáveis anteriormente descritas. As principais diferenças, identificadas do ponto de vista da estatística descritiva, verificaram-se ao nível do tipo de stress (farmacológico; falsos positivos - 63.64%, grupo de controlo – 40.74%), factores de risco (hipercolesterolemia; falsos positivos - 53.85%, grupo de controlo – 29.63%), ECG (fibrose; falsos positivos - 16.67%, grupo de controlo – 0%), Ecocardiograma (alteração da contractilidade segmentar; falsos positivos - 33.33%, grupo de controlo – 14.86%) e em relação aos eventos cardíacos posteriores (falsos positivos - 7.69%; grupo de controlo - 4.94%). A estatística inferencial permitiu apenas estabelecer uma relação estatisticamente significativa entre a existência de fibrose no ECG e a ocorrência de falsos positivos. Conclusão: Este estudo permitiu concluir que, de uma forma puramente descritiva, os casos falsos positivos se verificam mais predominantemente numa faixa etária média de 73.69 anos, no género feminino, com a localização das lesões na CPM a ser mais frequente no apex e mais rara no septo interventricular. O stress descritivamente mais associado a estes casos foi o stress farmacológico, com uma fracção de ejecção igual ou superior a 50%, com dois factores de risco associados, sendo os mais prevalentes a hipertensão arterial (HTA) e a hipercolesterolemia, sendo no entanto, este último, o factor de risco mais diferenciador em relação aos restantes casos. A maioria dos casos, em termos descritivos, não apresenta alterações no ECG, mas a existirem, a que mais se verifica é a fibrose. Relativamente ao ecocardiograma, existe uma maior prevalência de casos nos quais se verificam alterações neste exame complementar de diagnóstico, sendo a hipertrofia das paredes e a alteração da contractilidade segmentar do VE as alterações mais importantes, sendo, no entanto, este último, o factor mais diferenciador/característico. A prevalência descritiva de eventos cardíacos, num período de tempo após um ano da realização da CPM, é reduzida nos casos falsos positivos, mas ainda assim, superior à verificada nos restantes casos, o que em termos comparativos pressupõe uma deterioração em termos de prognóstico para estes pacientes. A análise estatística inferencial dos resultados obtidos permitiu apenas uma correlação entre a existência de fibrose no ECG e a ocorrência de falsos positivos. A análise de uma população geral de maiores dimensões, que permitisse a identificação de um número de falsos positivos igual ou superior a 30, possibilitaria, muito provavelmente, uma maior relação entre as diferentes amostragens e, consequentemente, uma base estatística que permitisse a obtenção de conclusões mais sólidas, estabelecendo/descartando as relações entre as várias variáveis em estudo, sendo esta, uma importante premissa a ter em conta para estudos futuros.

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We have examined the effect of the uncharged species of lidocaine (LDC) and etidocaine (EDC) on the acyl chain moiety of egg phosphatidylcholine liposomes. Changes in membrane organization caused by both anesthetics were detected through the use of EPR spin labels (5, 7 and 12 doxyl stearic acid methyl ester) or fluorescence probes (4, 6, 10, 16 pyrene-fatty acids). The disturbance caused by the LA was greater when the probes were inserted in more external positions of the acyl chain and decreased towards the hydrophobic core of the membrane. The results indicate a preferential insertion of LDC at the polar interface of the bilayer and in the first half of the acyl chain, for EDC. Additionally, 2 H NMR spectra of multilamellar liposomes composed by acyl chain-perdeutero DMPC and EPC (1:4 mol%) allowed the determination of the segmental order (S-mol) and dynamics (T-1) of the acyl chain region. In accordance to the fluorescence and EPR results, changes in molecular orientation and dynamics are more prominent if the LA preferential location is more superficial, as for LDC while EDC seems to organize the acyl chain region between carbons 2-8, which is indicative of its positioning. We propose that the preferential location of LDC and EDC inside the bilayers creates a "transient site", which is related to the anesthetic potency since it could modulate the access of these molecules to their binding site(s) in the voltage-gated sodium channel. (C) 2007 Elsevier B.V. All rights reserved.

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The research aimed to understand the challenges for the implementation of the proposed integration between the Civil Police and the Military Police in Rio Grande do Norte to the proposals of the SUSP. This study aimed to explore the gap with regard to the deepening of the possible causes that may hinder the implementation of integrated working between the police in public security, through a specific analysis on the state of Rio Grande do Norte. Was based on a theoretical framework that includes policies: general concepts, the steps of a public policy, the implementation stage , public security : conceptual definitions, policies on security in Brazil, the structure of public security in Brazil and systems police, Military Police x Civil Police: Roles and conflicts , integrating public security: the challenges to be overcome, the Unified public Safety (SUSP) and the main difficulties in the integration of the police. Being classified as to the purposes as an exploratory research on how to approach ranks as qualitative. The research unit was the Center for Integrated Operations Public Safety (CIOSP) through three subjects who were the chief CIOSP, the representative of the military police acting with the CIOSP, and representative civil police also active with the CIOSP. These subjects were chosen because of the understanding that individuals occupying senior positions would have more ability to respond to questions that guide the research problem. Data were collected through a set of interviews, qualitative data analysis was performed based content analysis, based on the definition of categories of analysis, gated time cross. With the results, it was revealed that the main problems of integration between the state police are treatment protocols, lack of political will and lack of infrastructure. The relationship between the Military Police and Civil Police in Rio Grande do Norte has differing cultural aspect, but can be considered as good value, professionalism and integrated operations. The implementation of CIOSP-RN followed the characteristics of the top-down model, the main difficulties in implementing the proposals of the SUSP, lack of own resources, the lack of standardization in public safety and the lack of professional training of public safety. It was concluded that with respect to the challenges to the implementation of the proposed integration between the Civil Police and the Military Police in Rio Grande do Norte to the proposals of the SUSP, the actions follow the characteristics of the top-down model, with no autonomy of administrators public to say in decisions, which restricts the view of the public safety of the state