987 resultados para pre-image attack


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Background: Surgical repair of pectus excavatum (PE) has become more popular due to improvements in the minimally invasive Nuss procedure. The pre-surgical assessment of PE patients requires Computerized Tomography (CT), as the malformation characteristics vary from patient to patient. Objective: This work aims to characterize soft tissue thickness (STT) external to the ribs among PE patients. It also presents a comparative analysis between the anterior chest wall surface before and after surgical correction. Methods: Through surrounding tissue segmentation in CT data, STT values were calculated at different lines along the thoracic wall, with a reference point in the intersection of coronal and median planes. The comparative analysis between the two 3D anterior chest surfaces sets a surgical correction influence area (SCIA) and a volume of interest (VOI) based on image processing algorithms, 3D surface algorithms, and registration methods. Results: There are always variations between left and right side STTs (2.54±2.05 mm and 2.95±2.97 mm for female and male patients, respectively). STTs are dependent on age, sex, and body mass index of each patient. On female patients, breast tissue induces additional errors in bar manual

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Background: Regulating mechanisms of branching morphogenesis of fetal lung rat explants have been an essential tool for molecular research. This work presents a new methodology to accurately quantify the epithelial, outer contour and peripheral airway buds of lung explants during cellular development from microscopic images. Methods: The outer contour was defined using an adaptive and multi-scale threshold algorithm whose level was automatically calculated based on an entropy maximization criterion. The inner lung epithelial was defined by a clustering procedure that groups small image regions according to the minimum description length principle and local statistical properties. Finally, the number of peripheral buds were counted as the skeleton branched ends from a skeletonized image of the lung inner epithelial. Results: The time for lung branching morphometric analysis was reduced in 98% in contrast to the manual method. Best results were obtained in the first two days of cellular development, with lesser standard deviations. Non-significant differences were found between the automatic and manual results in all culture days. Conclusions: The proposed method introduces a series of advantages related to its intuitive use and accuracy, making the technique suitable to images with different lightning characteristics and allowing a reliable comparison between different researchers.

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Pectus excavatum is the most common deformity of the thorax. Pre-operative diagnosis usually includes Computed Tomography (CT) to successfully employ a thoracic prosthesis for anterior chest wall remodeling. Aiming at the elimination of radiation exposure, this paper presents a novel methodology for the replacement of CT by a 3D laser scanner (radiation-free) for prosthesis modeling. The complete elimination of CT is based on an accurate determination of ribs position and prosthesis placement region through skin surface points. The developed solution resorts to a normalized and combined outcome of an artificial neural network (ANN) set. Each ANN model was trained with data vectors from 165 male patients and using soft tissue thicknesses (STT) comprising information from the skin and rib cage (automatically determined by image processing algorithms). Tests revealed that ribs position for prosthesis placement and modeling can be estimated with an average error of 5.0 ± 3.6 mm. One also showed that the ANN performance can be improved by introducing a manually determined initial STT value in the ANN normalization procedure (average error of 2.82 ± 0.76 mm). Such error range is well below current prosthesis manual modeling (approximately 11 mm), which can provide a valuable and radiation-free procedure for prosthesis personalization.

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Regulating mechanisms of branchingmorphogenesis of fetal lung rat explants have been an essential tool formolecular research.This work presents a new methodology to accurately quantify the epithelial, outer contour, and peripheral airway buds of lung explants during cellular development frommicroscopic images. Methods.Theouter contour was defined using an adaptive and multiscale threshold algorithm whose level was automatically calculated based on an entropy maximization criterion. The inner lung epithelium was defined by a clustering procedure that groups small image regions according to the minimum description length principle and local statistical properties. Finally, the number of peripheral buds was counted as the skeleton branched ends from a skeletonized image of the lung inner epithelia. Results. The time for lung branching morphometric analysis was reduced in 98% in contrast to themanualmethod. Best results were obtained in the first two days of cellular development, with lesser standard deviations. Nonsignificant differences were found between the automatic and manual results in all culture days. Conclusions. The proposed method introduces a series of advantages related to its intuitive use and accuracy, making the technique suitable to images with different lighting characteristics and allowing a reliable comparison between different researchers.

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Recently, regulating mechanisms of branching morphogenesis of fetal lung rat explants have been an essential tool for molecular research. The development of accurate and reliable segmentation techniques may be essential to improve research outcomes. This work presents an image processing method to measure the perimeter and area of lung branches on fetal rat explants. The algorithm starts by reducing the noise corrupting the image with a pre-processing stage. The outcome is input to a watershed operation that automatically segments the image into primitive regions. Then, an image pixel is selected within the lung explant epithelial, allowing a region growing between neighbouring watershed regions. This growing process is controlled by a statistical distribution of each region. When compared with manual segmentation, the results show the same tendency for lung development. High similarities were harder to obtain in the last two days of culture, due to the increased number of peripheral airway buds and complexity of lung architecture. However, using semiautomatic measurements, the standard deviation was lower and the results between independent researchers were more coherent.

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Background: Surgical repair of pectus excavatum (PE) has become more popular due to improvements in the minimally invasive Nuss procedure. The pre-surgical assessment of PE patients requires Computerized Tomography (CT), as the malformation characteristics vary from patient to patient. Objective: This work aims to characterize soft tissue thickness (STT) external to the ribs among PE patients. It also presents a comparative analysis between the anterior chest wall surface before and after surgical correction. Methods: Through surrounding tissue segmentation in CT data, STT values were calculated at different lines along the thoracic wall, with a reference point in the intersection of coronal and median planes. The comparative analysis between the two 3D anterior chest surfaces sets a surgical correction influence area (SCIA) and a volume of interest (VOI) based on image processing algorithms, 3D surface algorithms, and registration methods. Results: There are always variations between left and right side STTs (2.54±2.05 mm and 2.95±2.97 mm for female and male patients, respectively). STTs are dependent on age, sex, and body mass index of each patient. On female patients, breast tissue induces additional errors in bar manual

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Pectus excavatum is the most common deformity of the thorax. Pre-operative diagnosis usually includes Computed Tomography (CT) to successfully employ a thoracic prosthesis for anterior chest wall remodeling. Aiming at the elimination of radiation exposure, this paper presents a novel methodology for the replacement of CT by a 3D laser scanner (radiation-free) for prosthesis modeling. The complete elimination of CT is based on an accurate determination of ribs position and prosthesis placement region through skin surface points. The developed solution resorts to a normalized and combined outcome of an artificial neural network (ANN) set. Each ANN model was trained with data vectors from 165 male patients and using soft tissue thicknesses (STT) comprising information from the skin and rib cage (automatically determined by image processing algorithms). Tests revealed that ribs position for prosthesis placement and modeling can be estimated with an average error of 5.0 ± 3.6 mm. One also showed that the ANN performance can be improved by introducing a manually determined initial STT value in the ANN normalization procedure (average error of 2.82 ± 0.76 mm). Such error range is well below current prosthesis manual modeling (approximately 11 mm), which can provide a valuable and radiation-free procedure for prosthesis personalization.

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Pectus excavatum is the most common deformity of the thorax and usually comprises Computed Tomography (CT) examination for pre-operative diagnosis. Aiming at the elimination of the high amounts of CT radiation exposure, this work presents a new methodology for the replacement of CT by a laser scanner (radiation-free) in the treatment of pectus excavatum using personally modeled prosthesis. The complete elimination of CT involves the determination of ribs external outline, at the maximum sternum depression point for prosthesis placement, based on chest wall skin surface information, acquired by a laser scanner. The developed solution resorts to artificial neural networks trained with data vectors from 165 patients. Scaled Conjugate Gradient, Levenberg-Marquardt, Resilient Back propagation and One Step Secant gradient learning algorithms were used. The training procedure was performed using the soft tissue thicknesses, determined using image processing techniques that automatically segment the skin and rib cage. The developed solution was then used to determine the ribs outline in data from 20 patient scanners. Tests revealed that ribs position can be estimated with an average error of about 6.82±5.7 mm for the left and right side of the patient. Such an error range is well below current prosthesis manual modeling (11.7±4.01 mm) even without CT imagiology, indicating a considerable step forward towards CT replacement by a 3D scanner for prosthesis personalization.

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In a time of fierce competition between regions, an image serve as a basis to develop a strong sense of community, which fosters trust and cooperation that can be mobilized for regional growth. A positive image and reputation could be used in the promotional activities of the region benefiting all the stakeholders as a whole. Mega cultural events are frequently used to attract tourists and investments to a region, but also to enhance the city’s image. This study adopts a marketing/communication perspective of city’s image, and intends to explain how the image of the city is perceived by their residents. Specifically, we intend to compare the perceptions of residents that effectively participated in the Guimarães European Capital of Culture (ECOC) 2012 (engaged residents), and the residents that only assisted to the event (attendees). Several significant findings are reported and their implications for event managers and public policy administrators presented, along with the limitations of the study.

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Residents tend to have high expectations about the benefits of hosting a mega‐event. So, it was not surprising that the nomination of Guimarães, Portugal, as the 2012 European Capital of Culture (2012 ECOC) had raised great expectations in the local community towards its socio‐economic and cultural benefits. The present research was designed to examine the Guimarães residents’ perceptions on the impacts of hosting the 2012 ECOC approached in two different time schedules, the pre‐ and the post‐event, trying to capture the evolution of the residents` evaluation of its impacts. For getting the data, two surveys were applied to Guimarães` residents, one in the pre‐event phase, in 2011, and another in the post‐event phase, in 2013. This approach is uncommonly applied to Portugal data and it is even the first time it was done to a Portuguese European Capital of Culture. After a factor analysis, the results of t‐tests indicate that there were significant differences (p<0.05) between the samples from the pre‐ and post‐2012 ECOC on two positive impact factors (Community’ benefits and Residents’ benefits) and one negative impact factor (Economic, social and environmental costs). Respondents also showed a negative perception of the impacts in all dimensions, except Changes in habits of Guimarães residents.

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The nomination of Guimarães, a small city located in the northwest of Portugal, as European capital of culture (ECOC) in 2012 raised great expectations in the local community towards its socio-economic and cultural benefits. As noted by various authors, namely Kim and Petrick (2005), Kim, Gursoy and Lee (2006) and Gursoy, Chi, Ai and Chen (2011), residents tend to have high expectations about the benefits of hosting a mega-event, although they tend to recognize that some costs will result from it. Therefore, the present research was designed to examine the Guimarães residents’ perceptions on the impacts of the 2012 European capital of culture (2012 ECOC) on the city and the municipality of Guimarães before and after the mega-event and the differences found between the two time periods.

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1- Introdução: algumas notícias da comunicação social; 2 – O designado «Conselho de Prevenção de Corrupção»; 3 – Procuradoria-Geral da República (P.G.R.) e o Departamento Central de Investigação e Acção Penal (D.I.A.P.); 4 – Alguns sítios com relevo; 5 – Alguns dos problemas que podem ser colocados em relação à Responsabilidade das Empresas pelo Crime de Corrupção; 5.1 – Âmbito dos problemas a serem falados; 6 – Qual a noção de «empresas que vamos utilizar»?; 6.1 – A noção de «empresa» em sentido geral objectivo e penal; 7 – Mas que tipo de crimes de corrupção vamos falar?; 8 – O art. 11º do Código Penal e os crimes de corrupção no contexto do ordenamento jurídico português; 8.1 – No contexto do art. 11º do Código Penal, o que significa «em nome da pessoa colectiva»?; 8.2 – No contexto do art. 11º do Código Penal, o que significa «no interesse da pessoa colectiva»?; 8.2.1 – No contexto do art. 11º do Código Penal, o que significa «quando não há interesse colectivo»?; 9 – E haverá diferenças, por exemplo, entre o modo de funcionamento técnico-jurídico do art. 11º do Código Penal e o art. 3º do Regime das Infracções Anti-Económicas e Contra a Saúde Pública (R.I.A.E.C.S.P.)?; 10 – E como é que a Jurisprudência portuguesa, a que tivemos acesso - dado não haver ainda fartura de decisões neste campo -, estabelece o nexo de imputação de responsabilidade penal a uma pessoa colectiva e/ou organização?; 10.1 – Uma primeira pré-conclusão dentro do objectivo que pretendemos demonstrar na totalidade deste trabalho; 11 – Uma segunda pré-conclusão: será que as diferenças acima assinaladas, por exemplo, entre o modo de funcionamento técnico-jurídico do art. 11º do Código Penal e o art. 3º do Regime das Infracções Anti-Económicas e Contra a Saúde Pública (R.I.A.E.C.S.P.), são as únicas? Veja-se o caso, v.g., do art. 7º do Regime Geral das Infracções Tributárias (R.G.I.T.); 12 – Em face das duas pré-conclusões anteriores, faça-se aqui, neste breve ensaio, uma primeira grande conclusão; 13 – Uma (primeira) hipótese de solução; 14 – Que tipo de «empresa» podemos enquadrar no art. 11º do Código Penal?; 14.1 – De acordo com o referido anteriormente, podemos dizer que todas as «empresas» podem praticar os crimes previstos e punidos no Código Penal português?; 14.2 – De acordo com o referido antes, quais são as «empresas» que não podem praticar os crimes de corrupção que estão previstos e punidos no Código Penal português?; 14.3 – Uma outra pré-conclusão: 14.4 – Um esboço de um dos possíveis problemas; 14.4.1 – Mas, afinal, o que são Entidades Públicas Empresariais (E.P.E.)?; 14.5 – Outra hipótese de esboço de um outro dos possíveis problemas que aqui podemos encontrar; 14.6 – Nova pré-conclusão; 14.7 – Uma outra importante pergunta a fazer e a responder desde já; 14.7.1 - Alarguemos, pois, um pouco a nossa investigação para além do Código Penal português; 14.7.2 – O problema da responsabilidade penal das organizações e/ou «pessoas colectivas», rectius, neste breve ensaio, empresas, pela prática de crimes de corrupção previstos e punidos na mencionada Lei n.º 20/2008, de 21 de Abril («Responsabilidade penal por crimes de corrupção no comércio internacional e na actividade privada»); 14.7.3 – Mais algumas pré-conclusões; 15 - Em face das duas pré-conclusões anteriores, faça-se aqui, neste breve ensaio, uma segunda grande conclusão; 16 - O que também apresenta outras implicações como por exemplo na aplicação do crime de «branqueamento» quando nos fala em «corrupção» como «crime primário»; 17 – Outras interrogações; 18 – Conclusão final, mas não última, como nenhuma o pode ser em ciência; 19 – Hipótese de solução; 20 – Novos desenvolvimentos. § 1 - Introduction: some news media; 2 - The so-called "Council for the Prevention of Corruption”, 3 – “Attorney General's Office” (PGR) and the Central Bureau of Investigation and Penal Action (DIAP) 4 - Some sites with relief , 5 - Some of the problems that can be placed in relation to the Corporate Responsibility of the Crime of Corruption; 5.1 - Scope of issues to be spoken, 6 - What is the concept of "companies that we will use"?; 6.1 - The term “business” in a general purpose and criminal matters; 7 - What kind of crimes of corruption we talking about?; 8 - Art. 11 of the Penal Code and the crimes of corruption in the context of the Portuguese legal system; 8.1 - In the context of art. 11 of the Penal Code, which means "in the name of the legal person"?; 8.2 - In the context of art. 11 of the Penal Code, which means “in the interests of the legal person"?; 8.2.1 - In the context of art. 11 of the Penal Code, which means "where there is no collective interest"?; 9 - There will be differences, for example, between the operating mode of the Art. 11 of the Criminal Code and Art. 3 of the Legal Infractions Anti-Economic and Against Public Health (RIAECSP)?; 10 - And how does the case law of Portugal, we had access - as there still plenty of decisions in this field - makes a connection of allocating criminal liability to a legal person and / or organization?; 10.1 - A first pre-completion within the objective that we intend to demonstrate in all of this work; 11 - A second pre-conclusion: that the differences will be noted above, for example, between operating mode of the Art. 11 of the Criminal Code and Art. 3 of the Rules of the Offences Against Anti-Economics and Public Health (RIAECSP) are the only ones? Take the case v.g. of art. 7 of the Legal Framework of Tax Offences (RGIT) 12 - In view of the two pre-earlier conclusions, do it here, in this brief essay, a first major conclusion; 13 - A (first) chance for a solution, 14 - What kind “undertaking” we can frame the art. 11 of the Penal Code?; 14.1 - According to the above, we can say that all "companies" can practice the crimes defined and punished in the Portuguese Penal Code?; 14.2 - According to the mentioned before, what are the "business" who cannot practice corruption crimes that are planned and punished the Portuguese Penal Code?; 14.3 - Another pre-completion: 14.4 - A sketch of one of the possible problems; 14.4.1 - But after all the entities that are Public Enterprise (EPE)?; 14.5 - Another chance to draft another one of the possible problems that can be found here; 14.6 - New pre-completion; 14.7 - Another important question to ask and answer now; 14.7.1 - Let us expand, then, a little beyond our investigation of the Portuguese Penal Code; 14.7.2 - The problem of criminal liability of organizations and / or "legal persons", rectius, this brief essay, companies, for crimes of corruption provided for and punished mentioned in Law No. 20/2008 of 21 April ("Criminal liability for crimes of corruption in international trade and private activities"); 14.7.3 - Some more pre-conclusions; 15 - In view of the two pre-earlier conclusions, let it be here in this brief essay, a second major conclusion, 16 - Who also has other implications such as the application of the crime of "money laundering" when we talk about “corruption” as “primary crime”, 17 - Other questions; 18 - Bottom line, but not last, as the can be no science; 19 - Hypothesis solution; 20 - New developments.

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Minimally invasive cardiovascular interventions guided by multiple imaging modalities are rapidly gaining clinical acceptance for the treatment of several cardiovascular diseases. These images are typically fused with richly detailed pre-operative scans through registration techniques, enhancing the intra-operative clinical data and easing the image-guided procedures. Nonetheless, rigid models have been used to align the different modalities, not taking into account the anatomical variations of the cardiac muscle throughout the cardiac cycle. In the current study, we present a novel strategy to compensate the beat-to-beat physiological adaptation of the myocardium. Hereto, we intend to prove that a complete myocardial motion field can be quickly recovered from the displacement field at the myocardial boundaries, therefore being an efficient strategy to locally deform the cardiac muscle. We address this hypothesis by comparing three different strategies to recover a dense myocardial motion field from a sparse one, namely, a diffusion-based approach, thin-plate splines, and multiquadric radial basis functions. Two experimental setups were used to validate the proposed strategy. First, an in silico validation was carried out on synthetic motion fields obtained from two realistic simulated ultrasound sequences. Then, 45 mid-ventricular 2D sequences of cine magnetic resonance imaging were processed to further evaluate the different approaches. The results showed that accurate boundary tracking combined with dense myocardial recovery via interpolation/ diffusion is a potentially viable solution to speed up dense myocardial motion field estimation and, consequently, to deform/compensate the myocardial wall throughout the cardiac cycle. Copyright © 2015 John Wiley & Sons, Ltd.

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Given the dynamic nature of cardiac function, correct temporal alignment of pre-operative models and intraoperative images is crucial for augmented reality in cardiac image-guided interventions. As such, the current study focuses on the development of an image-based strategy for temporal alignment of multimodal cardiac imaging sequences, such as cine Magnetic Resonance Imaging (MRI) or 3D Ultrasound (US). First, we derive a robust, modality-independent signal from the image sequences, estimated by computing the normalized crosscorrelation between each frame in the temporal sequence and the end-diastolic frame. This signal is a resembler for the left-ventricle (LV) volume curve over time, whose variation indicates di erent temporal landmarks of the cardiac cycle. We then perform the temporal alignment of these surrogate signals derived from MRI and US sequences of the same patient through Dynamic Time Warping (DTW), allowing to synchronize both sequences. The proposed framework was evaluated in 98 patients, which have undergone both 3D+t MRI and US scans. The end-systolic frame could be accurately estimated as the minimum of the image-derived surrogate signal, presenting a relative error of 1:6 1:9% and 4:0 4:2% for the MRI and US sequences, respectively, thus supporting its association with key temporal instants of the cardiac cycle. The use of DTW reduces the desynchronization of the cardiac events in MRI and US sequences, allowing to temporally align multimodal cardiac imaging sequences. Overall, a generic, fast and accurate method for temporal synchronization of MRI and US sequences of the same patient was introduced. This approach could be straightforwardly used for the correct temporal alignment of pre-operative MRI information and intra-operative US images.

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While fluoroscopy is still the most widely used imaging modality to guide cardiac interventions, the fusion of pre-operative Magnetic Resonance Imaging (MRI) with real-time intra-operative ultrasound (US) is rapidly gaining clinical acceptance as a viable, radiation-free alternative. In order to improve the detection of the left ventricular (LV) surface in 4D ultrasound, we propose to take advantage of the pre-operative MRI scans to extract a realistic geometrical model representing the patients cardiac anatomy. This could serve as prior information in the interventional setting, allowing to increase the accuracy of the anatomy extraction step in US data. We have made use of a real-time 3D segmentation framework used in the recent past to solve the LV segmentation problem in MR and US data independently and we take advantage of this common link to introduce the prior information as a soft penalty term in the ultrasound segmentation algorithm. We tested the proposed algorithm in a clinical dataset of 38 patients undergoing both MR and US scans. The introduction of the personalized shape prior improves the accuracy and robustness of the LV segmentation, as supported by the error reduction when compared to core lab manual segmentation of the same US sequences.