Las madres solas en contextos urbanos europeos. Milán y Berlín : puntos en común y divergencias en los procesos de empobrecimiento

La comparación entre madres solas en una ciudad prospera, Milano (Italia), y una ciudad en crisis económica y laboral, Berlin (Alemania), se dirige a descubrir si existe un modelo único de empobrecimiento urbano, o bien si la construcción social de la pobreza tiene características contextuales. El estudio de las trayectorías biográficas de madres solas ha permitido la construcción de trayectorias ideal-típicas de empobrecimiento. Nuestro trabajo de campo muestra como los procesos de empobrecimiento tienden a divergir entre modelos locales. Entre las madres solas encontramos, por una parte, trayectorias de pobreza recurrente en Milano y, por otra, pobreza prolongada en Berlín.The comparison of single mothers in an affluent city, Milan (Italy), and another in economic and employment crisis, Berlin (Germany), aims to verify whether a common pattern of urban impoverishment does exist or poverty has contextual features. The dynamic analysis of biographical trajectories allows for the construction of ideal-typical trajectories of impoverishment. Our fieldwork demonstrates how impoverishment processes tend to diverge between local dynamic models. Among lone mothers we find, on the one hand, recurrent poverty in Milan and, on the other, continuous poverty in Berlin

Apical lesions of endodontic origin in diabetic patients An integrative systematic review

INTRODUÇÃO: O diabetes mellitus (DM) é uma doença endócrina que pode afetar diversas funções do sistema imunológico do indivíduo. Nos últimos anos vários artigos correlacionam a diabetes com o aparecimento de periodontite apical (AP) ou com insucesso do tratamento endodôntico e não cicatrização da lesão apical. OBJETIVOS: Revisar e integrar a bibliografia sobre uma possível relação entre lesões periapicais e diabetes e avaliar o sucesso de tratamentos endodônticos não cirúrgicos nestes pacientes. MATERIAIS E MÉTODOS: Revisão sistemática integrativa com busca no PubMed. RESULTADOS: Foram selecionados 12 artigos. 7 sobre a prevalência de AP em pacientes com DM, 3 sobre o resultado do tratamento endodôntico e 2 sobre ambos. DISCUSSÃO: Pacientes diabéticos são mais propensos a infecções orais devido às alterações imunológicas decorrentes da doença. A hiperglicemia crônica pode ser responsável por retardar o tempo de cicatrização de uma lesão levando a uma maior probabilidade de desenvolver lesões apicais crônicas e um atraso na cicatrização após o tratamento endodôntico até mesmo falha do tratamento. CONCLUSÃO: A diabetes mellitus parece estar associada ao aumento da prevalência de periodontite apical e com maior probabilidade de desenvolver lesões periapicais com características crônicas, mas o alto risco de bias e a presença de inúmeros artigos contraditórios sobre o assunto não nos permitem afirmar isso com absoluta certeza. O tratamento endodôntico tem menor probabilidade de sucesso em pacientes diabéticos, maior probabilidade de atrasos na cicatrização de lesões periapicais e maior probabilidade de desenvolver periodontite apical em dentes tratados endodonticamente.INTRODUCTION: Diabetes mellitus (DM) is an endocrine disease that can affect various functions of the individual's immune system. In recent years several articles correlate diabetes with the appearance of apical periodontitis (AP) or with failure of endodontic treatment and non-healing of the apical lesion. OBJECTIVES: Review and integrate the bibliography on a possible connection between periapical lesions and diabetes and to evaluate the success of non-surgical endodontic treatments in these patients. MATERIALS AND METHODS: Integrative systematic review with search through PubMed. RESULTS: 12 articles were selected. 7 on the prevalence of AP in DM patients, 3 on the outcome of endodontic treatment and 2 on both. DISCUSSION: Diabetic patients are more prone to oral infections due to immunological alterations brought by the disease. Chronic hyperglycemia can be responsible for slowing the healing time of a lesion leading to a greater probability of developing chronic apical lesions and a delay in healing following endodontic treatment even up to treatment failure. CONCLUSION: Diabetes mellitus seems to be associated with an increase in the prevalence of apical periodontitis and with a greater probability of developing periapical lesions with chronic characteristics, but the high risk of bias and the presence of numerous contradictory articles on the subject do not allow us to state this with absolute certainty. Endodontic treatment has a lower probability of success in diabetic patients, a greater probability of delays in the healing of periapical lesions and a greater probability of developing apical periodontitis in endodontically treated teeth

Development of Synchrotron Based Imaging Tools for Benign Prostatic Hyperplasia Using an Induced Canine Model

Benign prostatic hyperplasia (BPH) is a disease that develops spontaneously in men and dogs, and the dog is an accepted model to study BPH in men. As the gland can also be the site of a malignant cancer, definitive diagnosis relies on histological evaluation of prostate tissue following an invasive biopsy. The use of a new imaging technique, synchrotron-based phase contrast computed tomography (PC-CT) for excised prostates shows great detail of the internal structure of the gland, comparable to that of low power histology. Considering this fact, our main objective was to induce BPH in dogs using a combination of hormones dihydrotestosterone (DHT) and estradiol and verify if PC-CT imaging of in situ prostate glands of live dogs allowed for improved non-invasive imaging details compared to conventional medical imaging modalities and early diagnosis of BPH. Two studies were conducted to achieve the objectives. The first study involved the induction of BPH using intact male dogs with DHT and estradiol. The control group (n=3) received triolein carrier and the BPH induction group (n=3) received the hormone combination of DHT and estradiol (dissolved in triolein) injections three times/week for 35 weeks. Parameters that were assessed to diagnosis BPH were in vivo prostate volumes calculated using computed tomography (CT) images, volume of excised prostates determined using water displacement, 3D measurements of the excised gland, semen analysis, digital rectal exam (DRE), hormone analysis (estradiol, testosterone, DHT and canine prostate specific esterase CPSE), morphometric analysis and histological assessment of the tissue slides. The results showed that the gland volumes calculated both in vivo and ex vivo and the 3D measurements from BPH induction group were numerically higher than the control group. Sperm count decreased for all dogs but was reduced to zero or almost zero in the BPH induction group. The CPSE hormone analysis indicated that 1 dog from the treatment and 1 dog from the control group had BPH according to the manufacture’s defined threshold value. DHT hormone levels were higher for the induction group than controls throughout the entire study. This consequently affected the endogenous testosterone and estradiol, which were both decreased due to the negative feedback in the hypothalamic-pituitary-gonadal (HPG) axis. For DRE, prostates from all dogs were found to be enlarged in size by the end of the study and the histological diagnosis revealed that all dogs have a certain degree of BPH. The second study involved the imaging of all six dogs with conventional non-invasive modalities (magnetic resonance imaging, MRI; CT; positron emission tomography, PET-CT; ultrasound, US; radiographs) plus the innovative PC-CT technique at the Canadian Light Source (CLS). None of these techniques resulted in images with the same level of fine detail as that obtained with previous PC-CT imaging of excised canine prostates. Comparisons among images from the various modalities determined that the best modality for the visualization of the internal structures of the prostate gland such as capsule, parenchyma, septa, lobe, urethra and cysts was MRI (T2), followed by US and CT. PC-CT images were comparable with PET-CT, allowing the visualization of the lobes and urethra filled with tracer. In conclusion, all dogs developed BPH, either spontaneously (control group) or following induction (treatment group). Also, images of the in situ prostate gland of dogs were acquired for the first time at the CLS with the PC-CT technique. Although the quality and resolution was not as expected in comparison with PC-CT images of excised canine prostates, this technique shows promise and with additional study and development has the potential to become a useful diagnostic methodology

On the instability threshold of journal bearing supported rotors

Journal bearing supported rotors present two kinds of self-excited vibrations: oil-whirl and oil-whip. The first one is commonly masked by the rotor unbalance, hence being rarely associated with instability problems. Oil-whip is a severe vibration which occurs when the oil-whirl frequency coincides with the first flexural natural frequency of the shaft. In many cases, oil-whip is the only fluid-induced instability considered during the design stage; however, experimental evidences have shown that the instability threshold may occur much sooner, demanding a better comprehension of the instability mechanism. In this context, numerical simulations were made in order to improve the identification of the instability threshold for two test rig configurations: one on which the instability occurs on the oil-whip frequency, and another which became unstable before this threshold. Therefore, the main contribution of this paper is to present an investigation of two different thresholds of fluid-induced instabilities and their detectability on design stage simulations based on rotordynamic analysis using linear speed dependent coefficients for the bearings2014CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP131658/2010-7PROBRAL 341/102007/54647-

Evaluation of the Thermal Effects in Tilting Pad Bearing

The analysis of thermal effects is of expressive importance in the context of rotordynamics to evaluate the behavior of hydrodynamic bearings because these effects can influence their dynamic characteristics under specific operational conditions. For this reason, a thermohydrodynamic model is developed in this work, in which the pressure distribution in the oil film and the temperature distribution are calculated together. From the pressure distribution, the velocity distribution field is determined, as well as the viscous dissipation, and consequently, the temperature distribution. The finite volume method is applied to solve the Reynolds equation and the energy equation in the thermohydrodynamic model (THD). The results show that the temperature is higher as the rotational speed increases due to the shear rate of the oil film. The maximum temperature in the bearing occurs in the overloaded pad, near the outlet boundary. The experimental tests were performed in a tilting pad journal bearing operating in a steam turbine to validate the model. The comparison between the experimental and numerical results provides a good correlation. The thermohydrodynamic lubrication developed in this assignment is promising to consistently evaluate the behavior of the tilting pad journal bearing operating in relatively high rotational speeds

A comparison of flexible coupling models for updating in rotating machinery response

This paper analyzes the effects of the mathematical models of flexible couplings in rotating mechanical systems in terms of their vibrational behavior. The residual unbalance of the coupled shafts is considered to be the main source of vibration in the rotating system. The moments and the frequencies of the forces, which result from these effects, are close to the natural frequencies of the mechanical system. Since the coupling is considered to be a flexible component in the power transmission system, it introduces a certain amount of mass, damping and stiffness to the system, influencing its natural frequencies. The present work shows the modeling of a mechanical rotor-bearing-coupling system, through the finite element method, used in this case to analyze the transverse vibrations of the system. Different modeling techniques were taken into account for this purpose. Such models are recommended for flexible couplings to analyze their influence on the natural frequencies of the system and on the unbalance response of the system. Afterwards, a model updating was carried out to fit the coupling stiffness and damping coefficients, using the minimum quadratic technique. Some sensitivity of the proposed models was observed in relation to the coupling parameters.235246Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Experimental validation of a bearing wear model using the directional response of the rotor-bearing system

The present work gives continuity in the analysis of the wear influence on cylindrical hydrodynamic bearings by presenting an experimental validation of the wear model previously proposed by the authors. This validation is carried on using the frequency response of the rotor-bearings system in directional coordinates. For this purpose, a test rig was assembled in order to evaluate the behavior of the rotating system when supported by hydrodynamic bearings with different wear patterns. The experimental measurements are used to validate the wear model, comparing the anisotropy influence on the experimental and numerical responses. The simulated directional frequency responses showed a good agreement with the experimental ones, demonstrating the potential of the proposed wear model in satisfactorily represent its influence on the rotor-bearings system response in the frequency range where the numerical model was validated884CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPNão temNão temNão te