Image quality and dose analysis for a PA chest X-ray: comparison between AEC mode acquisition and manual mode using the 10 kVp ‘rule’

Purpose - To compare the image quality and effective dose applying the 10 kVp rule with manual mode acquisition and AEC mode in PA chest X-ray. Method - 68 images (with and without lesions) were acquired using an anthropomorphic chest phantom using a Wolverson Arcoma X-ray unit. These images were compared against a reference image using the 2 alternative forced choice (2AFC) method. The effective dose (E) was calculated using PCXMC software using the exposure parameters and the DAP. The exposure index (lgM provided by Agfa systems) was recorded. Results - Exposure time decreases more when applying the 10 kVp rule with manual mode (50%–28%) when compared with automatic mode (36%–23%). Statistical differences for E between several ionization chambers' combinations for AEC mode were found (p = 0.002). E is lower when using only the right AEC ionization chamber. Considering the image quality there are no statistical differences (p = 0.348) between the different ionization chambers' combinations for AEC mode for images with no lesions. Considering lgM values, it was demonstrated that they were higher when the AEC mode was used compared to the manual mode. It was also observed that lgM values obtained with AEC mode increased as kVp value went up. The image quality scores did not demonstrate statistical significant differences (p = 0.343) for the images with lesions comparing manual with AEC mode. Conclusion - In general the E is lower when manual mode is used. By using the right AEC ionising chamber under the lung the E will be the lowest in comparison to other ionising chambers. The use of the 10 kVp rule did not affect the visibility of the lesions or image quality.

10 kVp rule – An anthropomorphic pelvis phantom imaging study using a CR system: impact on image quality and effective dose using AEC and manual mode

Background - Pelvis and hip radiography are consistently found to be amongst the highest contributors to the collective effective dose (E) in all ten DOSE DATAMED countries in Europe, representing 2.8 to 9.4% of total collective dose (S) in the TOP 20 exams list. The level of image quality should provide all the diagnostic information in order not to jeopardise the diagnosis, but being able to provide the needed clinical information with the minimum dose. A recent study suggests further research to determine whether the “10 kVp rule” would have value for a range of examinations using Computed Radiography (CR) systems. As a “rule of thumb” increasing the kVp by 10 whilst halving the mAs is suggested to give a similar perceptual image quality when compared to the original exposure factors. Aims - In light of the 10kVp rule, this study aims to investigate the influence of tube potential (kVp) variation in relation to perceptual image quality and E for pelvis imaging using automatic exposure control (AEC) and non-AEC in a Computed Radiography (CR) system. Research questions - Does the 10kVp rule works for the pelvis in relation to image quality in a CR system? Does the image quality differs when the AEC is used instead of manual mode using the 10kVp rule and how this impacts on E?

Estimação de sub-registro de nascidos vivos pelo método de captura e recaptura, Sergipe

OBJETIVO: Estimar o número de ocorrências de nascidos vivos e, por conseqüência, o sub-registro civil de nascidos vivos. MÉTODOS: As bases de dados do Sistema Nacional de Informação sobre Nascidos Vivos e do Registro Civil do Instituto Brasileiro de Geografia e Estatística, nos segundo e terceiro trimestres de 2006 do estado de Sergipe, foram pareadas por relacionamento determinístico a partir do número da Declaração de Nascido Vivo. A desagregação geográfica adotada foi a de microrregião de residência da mãe. Os modelos de Huggins para populações fechadas foram aplicados para estimar as probabilidades de captura em cada base e o total de nascidos vivos ocorrido no período, dentro de cada desagregação geográfica. O aplicativo utilizado para as estimações foi o Software MARK®. RESULTADOS: O sub-registro civil no período analisado foi de 19,3%. A aplicação do método de captura-recaptura para estimar sub-registro de nascidos vivos é factível, inclusive para desagregações geográficas menores do que unidade da federação. O relacionamento determinístico foi prejudicado em quatro microrregiões, devido à falta de preenchimento do número da Declaração de Nascido Vivo na base do Instituto Brasileiro de Geografia e Estatística. Identificou-se que a idade da mãe afeta a probabilidade de captura pelo Registro Civil, característica de heterogeneidade na população de nascidos vivos. CONCLUSÕES: O método de captura-recaptura mostrou-se viável para a estimação de sub-registro de nascidos vivos.

Image quality and dose analysis in PA chest x-ray: comparison between AEC and manual mode acquisition using the 10 kVp rule

Purpose: To compare image quality and effective dose when the 10 kVp rule is applied with manual and AEC mode in PA chest X-ray. Methods and Materials: A total of 68 images (with and without lesions) were acquired of an anthropomorphic chest phantom in a Wolverson Arcoma X-ray unit. The images were evaluated against a reference image using image quality criteria and the 2 alternative forced choice (2 AFC) method by five radiographers. The effective dose was calculated using PCXMC software using the exposure parameters and DAP. The exposure index (lgM) was recorded. Results: Exposure time decreases considerably when applying the 10 kVp rule in manual mode (50%-28%) compared to AEC mode (36%-23%). Statistical differences for effective dose between several AEC modes were found (p=0.002). The effective dose is lower when using only the right AEC ionization chamber. Considering image quality, there are no statistical differences (p=0.348) between the different AEC modes for images with no lesions. Using a higher kVp value the lgM values will also increase. The lgM values showed significant statistical differences (p=0.000). The image quality scores did not present statistically significant differences (p=0.043) for the images with lesions when comparing manual with AEC modes. Conclusion: In general, the dose is lower in the manual mode. By using the right AEC ionising chamber the effective dose will be the lowest in comparison to other ionising chambers. The use of the 10 kVp rule did not affect the detectability of the lesions.

Synthesis of Sub-5 NM Co-Doped SnO2 nanoparticles and their structural microstructural, optical and photocatalytic properties

A swift chemical route to synthesize Co-doped SnO2 nanopowders is described. Pure and highly stable Sn1-xCoxO2-delta (0 <= x <= 0.15) crystalline nanoparticles were synthesized, with mean grain sizes <5 nm and the dopant element homogeneously distributed in the SnO2 matrix. The UV-visible diffuse reflectance spectra of the Sn1-xCoxO2-delta samples reveal red shifts, the optical bandgap energies decreasing with increasing Co concentration. The samples' Urbach energies were calculated and correlated with their bandgap energies. The photocatalytic activity of the Sn1-xCoxO2-delta samples was investigated for the 4-hydroxylbenzoic acid (4-HBA) degradation process. A complete photodegradation of a 10 ppm 4-HBA solution was achieved using 0.02% (w/w) of Sn0.95Co0.05O2-delta nanoparticles in 60 min of irradiation. (C) 2014 Elsevier B.V. All rights reserved.

Sub-micron structuring of silicon using femtosecond laser interferometry

We report the fabrication of planar sub-micron gratings in silicon with a period of 720 nm using a modified Michelson interferometer and femtosecond laser radiation. The gratings consist of alternated stripes of laser ablated and unmodified material. Ablated stripes are bordered by parallel ridges which protrude above the unmodified material. In the regions where ridges are formed, the laser radiation intensity is not sufficient to cause ablation. Nevertheless, melting and a significant temperature increase are expected, and ridges may be formed due to expansion of silicon during resolidification or silicon oxidation. These conclusions are consistent with the evolution of the stripes morphology as a function of the distance from the center of the grating.

10 kVp rule - An anthropomorphic pelvis phantom imaging study using a CR system: impact on image quality and effective dose using AEC and manual mode

Purpose: This study aims to investigate the influence of tube potential (kVp) variation in relation to perceptual image quality and effective dose for pelvis using automatic exposure control (AEC) and non-AEC in a computed radiography (CR) system. Methods and Materials: To determine the effects of using AEC and non-AEC by applying the 10 kVp rule in two experiments using an anthropomorphic pelvis phantom. Images were acquired using 10 kVp increments (60-120 kVp) for both experiments. The first experiment, based on seven AEC combinations, produced 49 images. The mean mAs from each kVp increment were used as a baseline for the second experiment producing 35 images. A total of 84 images were produced and a panel of 5 experienced observers participated for the image scoring using the 2 AFC visual grading software. PCXMC software was used to estimate the effective dose. Results: A decrease in perceptual image quality as the kVp increases was observed both in non-AEC and AEC experiments, however no significant statistical differences (p> 0.05) were found. Image quality scores from all observers at 10 kVp increments for all mAs values using non-AEC mode demonstrates a better score up to 90 kVp. Effective dose results show a statistical significant decrease (p=0.000) on the 75th quartile from 0.3 mSv at 60 kVp to 0.1 mSv at 120 kVp when applying the 10 kVp rule in non-AEC mode. Conclusion: No significant reduction in perceptual image quality is observed when increasing kVp whilst a marked and significant effective dose reduction is observed.

Sub-notificação de reacções adversas medicamentosas : um problema com solução? : contribuição para o conhecimento da sub-notificação de RAMs em Portugal e implementação de medidas minimizadoras do impacte

RESUMO - Introdução: As Reacções Adversas Medicamentosas (RAMs) constituem um grave problema de Saúde Pública em termos da mortalidade e morbilidade provocadas, tendo também um impacto económico considerável nos Sistemas de Saúde. Os Sistemas de Notificacão Espontânea de RAMs são considerados como o método de vigilância de medicamentos mais eficaz, sendo a sub-notificação de RAMs uma das suas maiores limitações. Em termos globais, foi estimado que apenas 6% de todas as reacções adversas são notificadas. Portugal apresenta uma taxa de notificação de RAMs relativamente baixa quando comparada com os países mais notificadores da Europa. São objectivos deste estudo: 1) caracterizar as atitudes e os comportamentos dos médicos, dos farmacêuticos e dos enfermeiros em Portugal Continental relativamente à notificação de RAMs; e 2) caracterizar a efectividade de intervenções educacionais destinadas a reduzir a sub-notificação de RAMs. Métodos: Numa primeira fase será efectuado um estudo de caso-controlo em médicos, farmacêuticos e enfermeiros de Portugal Continental, a exercer actividade no Servico Nacional de Saúde (SNS), de modo a caracterizar as suas atitudes e comportamentos relativamente à notificação de RAMs. Como casos serão considerados os Profissionais de Saúde que notificaram pelo menos uma RAM num determinado período e os controlos os Profissionais de Saúde que não notificaram qualquer RAM nesse mesmo período, sendo estes útimos seleccionados aleatoriamente. O estudo será conduzido através de um questionário de auto-resposta, em que as questões relativas às atitudes e comportamentos são baseadas nos “sete pecados mortais” de Inman. Será utilizada uma Escala Visual Analógica para registar as respostas, podendo estas ir de zero (totalmente em desacordo) até 10 (totalmente de acordo). Será utilizada uma análise de regressão logística para determinar o odds ratio ajustado (ORadj) da notificação de RAMs para uma mudança de exposição correspondente ao range interquartil para cada atitude. Numa segunda fase, será efectuado ensaio aleatorizado controlado de cluster, para caracterizar a efectividade das intervenções educacionais realizadas sobre as causas identificadas na primeira parte do trabalho, com o intuito de reduzir a sub-notificação de RAMs. Com base em informacão de 2007 foram identificados 43 clusters dispersos pelas várias Regiões de Saúde. As intervenções educacionais são compostas por uma apresentação com uma hora de duração complementada por um folheto recordatório. Serão ainda realizados dois sub-estudos, em que o V1.0, Final 28Set09 viii Sub-notificação de RAMs em Portugal – Um problema com solução ? primeiro tentará caracterizar o efeito de contaminação entre Profissionais de Saúde e o segundo pretende caracterizar a duração do efeito das intervenções educacionais. Resultados a atingir: Pretende-se, com a implementação deste projecto, aumentar o número de notificações de RAMs pelos médicos, farmacêuticos e enfermeiros em cerca de 110%, de modo a atingir-se uma taxa de notificação de aproximadamente 300 notificações por milhão de habitantes por ano (i.e., multiplicar por 2,1 o número notificações existentes). -------------------ABSTRACT - Introduction: The Adverse Drug Reactions (ADRs) are a serious Public Health problem in terms of mortality and morbidity caused, being also an economic burden for the health systems. The Spontaneous Adverse Event Reporting Systems are considered as the most effective drug surveillance methods, in which the ADR under-reporting represents one of its biggest limitations. It was estimated that only 6% of all adverse reactions are notified globally. When comparing with high ADR reporting rate countries Portugal shows a low ADR reporting rate. This study aims to: 1) characterize the physicians, pharmacists and nurses attitudes and behaviours related to ADR under-reporting; 2) characterize the educational interventions effectiveness to decrease the ADRs under-reporting. Methods: During a first phase a case-control study will be conducted in physicians, pharmacists and nurses in Continental Portugal working in the National Health System (NHS) in order to characterize their attitudes and behaviours related to ADR reporting. The Healthcare Professionals that have reported at least one ADR during a determined period will be considered as the cases and those that have not reported any ADR during the same period will be considered as the controls. The controls will be randomly selected. The study will be conducted through a self-administered questionnaire in which the questions related to the attitudes and behaviours are based in the Inmans’s “seven mortal sins”. A Visual Analogue Scale will be used to record the responses. The responses can range from 0 (totally disagree) to 10 (totally agree). Logistic regression will be used to determine the ADR reporting adjusted odds ratio (ORadj) for a change in the exposure corresponding to the interquartile range for each attitude. In the second phase of the study a cluster-randomized controlled trial will be conducted to characterize the educational interventions effectiveness focused on the first phase identified causes with the aim to decrease the ADRs under-reporting. Based in 2007’s information 43 clusters have been identified throughout the several Health Regions. The educational interventions are composed of one hour presentation complemented by an informational leaflet. Two sub-studies will be also conducted in which the first one will try to characterize the contamination effect between the Healthcare Professionals and the second to characterize the educational interventions effect duration. V1.0, Final 28Set09 x Sub-notificação de RAMs em Portugal – Um problema com solução ? Outcome: With the project implementation an increase of the ADR notifications performed by the physicians, pharmacists and nurses by 110% is aimed in order to obtain approximately 300 notifications per million habitants per year (i.e., multiply by 2,1 the existent notifications).

Evolução da ocupação e da perda de solo numa pequena sub-bacia da Bacia Hidrográfica do Rio Sado

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia do Ambiente,Perfil Gestão de Sistemas Ambientais

Voltage Magnitude Analysis Considering Load Curtailment Minimization in Sub-Transmission Networks with Distributed Generators

Most of distribution generation and smart grid research works are dedicated to the study of network operation parameters, reliability among others. However, many of this research works usually uses traditional test systems such as IEEE test systems. This work proposes a voltage magnitude study in presence of fault conditions considering the realistic specifications found in countries like Brazil. The methodology considers a hybrid method of fuzzy set and Monte Carlo simulation based on the fuzzyprobabilistic models and a remedial action algorithm which is based on optimal power flow. To illustrate the application of the proposed method, the paper includes a case study that considers a real 12 bus sub-transmission network.

Voltage Analysis and Load Curtailment Minimization in Sub-transmission Networks with Distributed Generation

Most of distributed generation and smart grid research works are dedicated to network operation parameters studies, reliability, etc. However, many of these works normally uses traditional test systems, for instance, IEEE test systems. This paper proposes voltage magnitude and reliability studies in presence of fault conditions, considering realistic conditions found in countries like Brazil. The methodology considers a hybrid method of fuzzy set and Monte Carlo simulation based on the fuzzy-probabilistic models and a remedial action algorithm which is based on optimal power flow. To illustrate the application of the proposed method, the paper includes a case study that considers a real 12-bus sub-transmission network.

In oboedientia, sine proprio, et in castitate, sub clausura: a ordem de Santa Clara em Portugal (séc. xiii-xiv)

Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Doutor em História (Especialidade em História Económica e Social Medieval)

Expressão de Aterosclerose Sub-Clínica para Diferentes Factores de Risco Cardiovasculares em Populações Jovens

INTRODUCTION: Carotid intima-media thickness (cIMT) is considered an early marker for atherosclerosis, but there are few studies on the expression of this marker in younger populations. OBJECTIVES: To evaluate cIMT in younge patients (aged 30-50 years) and its expression according to cardiovascular risk factors. METHODS: We analyzed individuals admitted for an invasive cardiac procedure. Normal cIMT was defined as < 0.90 mm, thickened as 0.90-1.50 mm and atherosclerotic plaque as > 1.50 mm. Lipid profile, anthropometric parameters, fasting blood glucose and estimated GFR were also determined. RESULTS: A total of 106 patients were included (59% male), with a mean age of 43 +/- 5 years, 36% with hypertension, 22% smokers, 32% with known hyperlipidemia, 16% with diabetes, 39% under statin therapy and 40% with metabolic syndrome (AHA/NHLBI definition). Mean cIMT was 0.69 +/- 0.26 mm, and was normal in 74% of the patients, thickened in 20% and with atherosclerotic plaques in 6%. cIMT correlated directly with age (r = 0.26, p = 0.007), log fasting glucose (r = 0.21, p = 0.04), and log triglycerides (r = 0.24, p = 0.017), and tended to correlate with the number of components of metabolic syndrome (r = 0.17, p = 0.08). However, on multivariate analysis, only age remained as an independent predictor (r = 0.29, p = 0.005). Diabetic patients had greater cIMT (0.81 +/- 0.22 vs. 0.67 +/- 0.26 mm, p = 0.039) and there was a trend for greater cIMT in those with metabolic syndrome (0.75 +/- 0.29 vs. 0.66 +/- 0.23 mm, p = 0.09). There were no differences for the other risk factors, A higher number of risk factors in a single patient showed a trend for increased cIMT (p = 0.083) CONCLUSIONS: Age is the only independent determinant of cIMT in a young population. Diabetic patients have greater cIMT and a trend was seen in those with metabolic syndrome, possibly influenced by its relation with diabetes, one of the components of the metabolic syndrome.

Description of an injury in a human caused by a false tocandira (Dinoponera gigantea, Perty, 1833) with a revision on folkloric, pharmacological and clinical aspects of the giant ants of the genera Paraponera and Dinoponera (sub-family Ponerinae)

The authors observed an injury caused by the sting of a false tocandira ant in the hand of an amateur fisherman and they describe the clinical findings and the evolution of the envenoming, which presented an acute and violent pain, cold sweating, nausea, a vomiting episode, malaise, tachycardia and left axillary's lymphadenopathy. About three hours after the accident, still feeling intense pain in the place of the sting, he presented an episode of great amount of blood in the feces with no history of digestive, hematological or vascular problems. The intense pain decreased after eight hours, but the place stayed moderately painful for about 24 hours. In that moment, he presented small grade of local edema and erythema. The authors still present the folkloric, pharmacological and clinical aspects related to the tocandiras stings, a very interesting family of ants, which presents the largest and more venomous ants of the world.

Ambivalent Islam: the identity construction of Muslims under Portuguese colonial rule

This article wishes to contribute to the study of the historical processes that have been spotting Muslim populations as favourite targets for political analysis and governance. Focusing on the Portuguese archives, civil as well as military, the article tries to uncover the most conspicuous identity representations (mainly negative or ambivalent) that members of Portuguese colonial apparatus built around Muslim communities living in African colonies, particularly in Guinea-Bissau and Mozambique. The paper shows how these culturally and politically constructed images were related to the more general strategies by which Portuguese imagined their own national identity, both as ‘European’ and as ‘coloniser’ or ‘imperial people’. The basic assumption of this article is that policies enforced in a context of inter-ethnic and religious competition are better understood when linked to the identity strategies inherent to them. These are conceived as strategic constructions aimed at the preservation, the protection and the imaginary expansion of the subject, who looks for groups to be included in and out-groups to reject, exclude, aggress or eliminate. We think that most of the inter-ethnic relationships and conflicts, as well as the very experience of ethnicity, are born from this identity matrix.