Image quality in diagnostic radiology

This chapter provides a theoretical background about image quality in diagnostic radiology. Digital image representation and also image quality evaluation methods are here discussed. An overview of methods for quality evaluation of diagnostic imaging procedures is provided. Digital image representation and primary physical image quality parameters are also discussed, including objective image quality measurements and observer performance methods.

Evaluation of the improvements on pharmacy technicians' work practices after implementation of operational procedures

Several antineoplasic drugs have been demonstrated to be carcinogenic or to have mutagenic and teratogenic effects. The greatest protection is achieved with the implementation of administrative and engineering controls and safety procedures. Objective: to evaluate the improvements on pharmacy technicians' work practices, after the implementation of operational procedures related to individual protection, biologic safety cabinet disinfection and cytotoxic drug preparation. Method: case-study in a hospital pharmacy undergoing a certification process. Six pharmacy technicians were observed during their daily activities. Characterization of the work practices was made using a checklist based on ISOPP and PIC guidelines. The variables studied concerning cleaning/disinfection procedures, personal protective equipment and procedures for preparing cytotoxic drugs. The same work practices were evaluated after four months of operational procedures implementation. Concordance between work practices and guidelines was considered to be a quality indicator (guidelines concordance practices number/total number of practices x 100). Results: improvements were observed after operational procedures implementation. An improvement of 6,25% in personal protective equipment practice was achieved by changing second pair of gloves every thirty minutes. The major progress, 10%, was obtained in disinfection procedure, where 80% of tasks are now realized according to guidelines.By now, we hot an improvement of only 1% at drug preparation procedure by placing one cytotoxic drug at a time inside the biological safety cabinet. Then, 85% of practices are according to guidelines. Conclusion: before operational procedures implementation 80,3% of practices were according to the guidelines, while now is 84,4%. This indicates that is necessary to review the procedures frequently in the benefit to reduce the risks associated with handling cytotoxic drugs and maintenance of drug specifications.

Syntheses, Molecular Structures, Electrochemical Behavior, Theoretical Study, and Antitumor Activities of Organotin(IV) Complexes Containing 1-(4-Chlorophenyl)-1-cyclopentanecarboxylato Ligands

The organotin(IV) compounds [Me2Sn(L)(2)] (1), [Et(2)sn(L)(2)] (2), [(Bu2Sn)-Bu-n(L)(2)] (3), [(n)Oct(2)Sn(L)(2)] (4), [Ph2Sn(L)(2)] (5), and [PhOSnL](6) (6) have been synthesized from the reactions of 1-(4-chlorophenyl)-1-cyclopentanecarboxylic acid (HL) with the corresponding diorganotin(IV) oxide or dichloride. They were characterized by IR and multinuclear NMR spectroscopies, elemental analysis, cyclic voltammetry, and, for 2, 3, 4 and 6, single crystal X-ray diffraction analysis. While 1-5 are mononuclear diorganotin (IV) compounds, the X-ray diffraction of 6 discloses a hexameric drumlike structure with a prismatic Sn6O6 core. All these complexes undergo irreversible reductions and were screened for their in vitro antitumor activities toward HL-60, BGC-823, Bel-7402, and KB human cancer cell lines. Within the mononuclear compounds, the most active ones (3, 5) are easiest to reduce (least cathodic reduction potentials), while the least active ones (1, 4) are the most difficult to reduce. Structural rearrangements (i.e., Sn-O bond cleavages and trans-to-cis isomerization) induced by reduction, which eventually can favor the bioactivity, are disclosed by theoretical/electrochemical studies.

Theoretical Analysis of Multimodal Four-Wave Mixing in Optical Microwires

Optical fiber microwires (OFMs) are nonlinear optical waveguides that support several spatial modes. The multimodal generalized nonlinear Schrodinger equation (MM-GNLSE) is deduced taking into account the linear and nonlinear modal coupling. A detailed theoretical description of four-wave mixing (FWM) considering the modal coupling is developed. Both, the intramode and the intermode phase-matching conditions is calculated for an optical microwire in a strong guiding regime. Finally, the FWM dynamics is studied and the amplitude evolution of the pump beams, the signal and the idler are analyzed.

Adequações curriculares: perspetivas e práticas de planeamento e intervenção

Com este artigo pretende-se sistematizar e discutir os resultados e conclusões de alguns estudos sobre adequações curriculares para dar resposta às necessidades educativas especiais, realizados no âmbito do mestrado em educação especial na Escola Superior de Educação de Lisboa. Após um breve enquadramento teórico, apresentam-se resultados e conclusões sobre as perspetivas de professores de diferentes ciclos de escolaridade em relação à gestão do currículo, às necessidades educativas especiais e à forma de definição das medidas educativas e curriculares a adotar. Confrontam-se depois estes resultados com as medidas efetivamente expressas nos documentos organizadores da intervenção com estes alunos e ainda com os resultados de observações realizadas em sala de aula. Conclui-se que um longo caminho já foi percorrido no que se refere a valores e princípios, mas que é necessário reforçar as componentes pedagógicas e didáticas do ensino destes alunos, de forma a que a inclusão não se reduza apenas a um processo de socialização e conduza a uma real aprendizagem.

A aprendizagem cooperativa como ferramenta para a inclusão

Dissertação apresentada à Escola Superior de Educação de Lisboa para obtenção do grau de Mestre em Ciências da Educação - Especialização em Educação Especial, Domínio Cognição e Multideficiência

Coordenação e fiscalização de obras na empresa Landway, S.A.

Relatório de Estágio para obtenção do grau de Mestre em Engenharia na Área de Especialização em Edificações

Optimising protocol of acquisition and post-processing procedures in the assessment of coronary artery disease by computed tomography

Coronary artery disease (CAD) is currently one of the most prevalent diseases in the world population and calcium deposits in coronary arteries are one direct risk factor. These can be assessed by the calcium score (CS) application, available via a computed tomography (CT) scan, which gives an accurate indication of the development of the disease. However, the ionising radiation applied to patients is high. This study aimed to optimise the protocol acquisition in order to reduce the radiation dose and explain the flow of procedures to quantify CAD. The main differences in the clinical results, when automated or semiautomated post-processing is used, will be shown, and the epidemiology, imaging, risk factors and prognosis of the disease described. The software steps and the values that allow the risk of developingCADto be predicted will be presented. A64-row multidetector CT scan with dual source and two phantoms (pig hearts) were used to demonstrate the advantages and disadvantages of the Agatston method. The tube energy was balanced. Two measurements were obtained in each of the three experimental protocols (64, 128, 256 mAs). Considerable changes appeared between the values of CS relating to the protocol variation. The predefined standard protocol provided the lowest dose of radiation (0.43 mGy). This study found that the variation in the radiation dose between protocols, taking into consideration the dose control systems attached to the CT equipment and image quality, was not sufficient to justify changing the default protocol provided by the manufacturer.

Acylated cyanoimido-complexes trans-[Mo(NCN){NCN(O)R}(DPPE)(2)]Cl and their reactons with electrophiles: Chemical, electrochemical and theoretical study

Treatment of a dichloromethane solution of trans-[Mo(NCN){NCNC(O)R}(dppe)(2)]Cl [R = Me (1a), Et (1b)] (dppe = Ph2PCH2CH2PPh2) with HBF4, [Et3O][BF4] or EtC(O)Cl gives trans-[Mo(NCN)Cl-(dppe)(2)]X [X = BF4 (2a) or Cl (2b)] and the corresponding acylcyanamides NCN(R')C(O)Et (R' = H, Et or C(O)Et). X-ray diffraction analysis of 2a (X = BF4) reveals a multiple-bond coordination of the cyanoimide ligand. Compounds 1 convert to the bis(cyanoimide) trans-[Mo(NCN)(2)(dppe)(2)] complex upon reaction with an excess of NaOMe (with formation of the respective ester). In an aprotic medium and at a Pt electrode, compounds 1 (R = Me, Et or Ph) undergo a cathodically induced isomerization. Full quantitative kinetic analysis of the voltammetric behaviour is presented and allows the determination of the first-order rate constants and the equilibrium constant of the trans to cis isomerization reaction. The mechanisms of electrophilic addition (protonation) to complexes 1 and the precursor trans[Mo(NCN)(2)(dppe)(2)], as well as the electronic structures, nature of the coordination bonds and electrochemical behaviour of these species are investigated in detail by theoretical methods which indicate that the most probable sites of the proton attack are the oxygen atom of the acyl group and the terminal nitrogen atom, respectively.

Redox-active cytotoxic diorganotin(IV) cycloalkylhydroxamate complexes with different ring sizes: Reduction behaviour and theoretical interpretation

Two series of new diorganotin(IV) cycloalkylhydroxamate complexes with different ring sizes (cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl), formulated as the mononuclear [R2Sn(HL)(2)] (1:2) (a, R=Bu-n and Ph) and the polymeric [R2SnL](n) (1:1) (b, R=Bu-n) compounds, were prepared and fully characterized. Single crystal X-ray diffraction for [(Bu2Sn)-Bu-n{C5H9C(O)NHO}(2)] (3a) discloses the cis geometry and strong intermolecular NH center dot center dot center dot O interactions. The in vitro cytotoxic activities of the complexes were evaluated against HL-60, Bel-7402, BGC-823 and KB human tumour cell lines, the greater activity concerning [(Bu2Sn)-Bu-n(HL)(2)] [HL=C3H5C(O)NHO (1a), C6H11C(O)NHO (4a)] towards BGC-823. The complexes undergo, by cyclic voltammetry and controlled-potential electrolysis, one irreversible overall two-electron cathodic process at a reduction potential that does not appear to correlate with the antitumour activity. The electrochemical behaviour of [R2Sn(C5H9C(O)NHO)(2)] [R=Bu-n (3a), Ph (7a)] was also investigated using density functional theory (DFT) methods, showing that the ultimate complex structure and the mechanism of its formation are R dependent: for the aromatic (R = Ph) complex, the initial reduction step is centred on the phenyl ligands and at the metal, being followed by a second reduction with Sn-O and Sn-C ruptures, whereas for the alkyl (R=Bu-n) complex the first reduction step is centred on one of the hydroxamate ligands and is followed by a second reduction with Sn-O bond cleavages and preservation of the alkyl ligands. In both cases, the final complexes are highly coordinative unsaturated Sn-II species with the cis geometry, features that can be of biological significance.

Electrorheology study of a series of LC cyanobiphenyls: Experimental and theoretical treatment

In this work we study the electro-rheological behaviour of a series of four liquid crystal (LC) cyanobiphenyls with a number of carbon atoms in the alkyl group, ranging from five to eight (5CB–8CB). We present the flow curves for different temperatures and under the influence of an external electric field, ranging from 0 to 3 kV/mm, and the viscosity as a function of the temperature, for the same values of electric field, obtained for different shear rates. Theoretical interpretation of the observed behaviours is proposed in the framework of the continuum theory of Leslie–Ericksen for low molecular weight nematic LCs. In our analysis, the director alignment angle is only a function of the ratio between the shear rate and the square of the electric field – boundary conditions are neglected. By fitting the theoretical model to the experimental data, we are able to determine some viscosity coefficients and the dielectric anisotropy as a function of temperature. To interpret the behaviour of the flow curves near the nematic–isotropic transitions, we apply the continuum theory of Olmsted–Goldbart, which extends the theory of Leslie–Ericksen to the case where the degree of alignment of the LC molecules can also vary.

A importância do planeamento e orçamentação nas empreitadas de obras de instalações mecânicas

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Mecânica

Comparison study of procedures for aspiration of biopsy samples

Introduction: The samples obtained from fine needle aspiration in liquid base cytology (FNAC) are often limited by scarce cellularity compared to the amount of colloid and presence of blood. Accordingly, it was important to test alternative technical procedures so as to maximize the cellularity of each sample. Objective: To compare the morphological features and cellularity of the three procedures in the FNAC cytodiagnosis of the thyroid. Methods: A total of 31 cases were each subjected to a cell block and ThinPrep preparation as well as a routine smear. The observation and analysis was performed using an optical microscope. Cytological diagnosis of each cell block case was objectively analysed for cellularity, presence of background and cellular preservation. Each smear and ThinPrep case was analysed for the presence or absence of cells. The data was analysed with Microsoft Excel (Office 2010) and SPSS (Statistical Package of Social Science) version 15.0 for Windows. Results: Of 31 cases, only 20 had thyroid cells in the cell block and ThinPrep preparations, however, all smear cases contained thyroid cells. Some background was found in 30 Cell block cases with only 5 of these containing well preserved cells for cytodiagnosis. Conclusions: As indicated by the results, smear is the most appropriate procedure for FNAC of the thyroid.

Acompanhamento da construção do edifício Focus Lx na Avenida António Augusto de Aguiar

Relatório de Estágio para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Edificações