Modelització i simulació del motor d'inducció en règim transitori amb PSIM

El present treball pretén modelitzar i simular el motor d’inducció trifàsic en règim transitori amb PSIM 6.0 Demo(la versió del programa que s’utilitza actualment a l’Escola Politècnica Superior de la UdG), però també s’estudia el model en règim permanent, per tal de comparar a nivell teòric els resultats dels dos règims. Primer cal entendre i implementar el model del motor d’inducció, i així obtenir l'esquema equivalent en règim transitori, per després poder-lo simular. Abans de dur a terme la simulació, cal obtenir els paràmetres del circuit equivalent del motor real per introduir-los al programa informàtic, amb la finalitat de tenir precisió en les respostes. Aquests valors s’obtindran mitjançant assajos necessaris al laboratori. Posteriorment, es fan simulacions i pràctiques reals amb el motor treballen en diferents condicions per veure el seu comportament, i així poder comparar els resultats de la simulació amb els valors reals. També s’implementa un estudi de la influencia dels paràmetres interns en el funcionament del motor. Així es podrà visualitzar i comparar les respostes de diferents variables en cadascunes de les simulacions que es duguin a terme. Finalment, seria interessant la introducció de la màquina d’inducció trifàsica actuant com a generador en la simulació.Aquest és un estudi en el qual se simula la màquina d'inducció trifàsic en règim transitori i en règim permanent mitjançant l'ús del PSIM, que és el programa informàtic de simulació

Millora d'un motor monocilíndric de 4T

En el nostre treball final de carrera tindrem com objecte la millora de les prestacions d’un motor de 4T per a una motocicleta d’enduro. L’augment de potència s’aconseguirà des de diferents perspectives, variant el sistema d’admissió, el canvi de la distribució de les vàlvules de la culata o variant la lubrificació del pistó. Per realitzar l’objecte d’aquest treball utilitzarem com a base de l’estudi el motor de 4T de la FSE 450 del 2004 de GASGAS Motos SA. El motor de 4T utilitzat està orientat cap a una utilització d’enduro, per tant amb unes característiques de parell determinades. Partirem de l’anàlisi d’un motor amb sistema d’admissió per depressió (carburador convencional) idesprés instal·larem el sistema d’injecció indirecta monopunt. La millora també afectarà a l’estil de conducció de la motocicleta, per tant comentarem els resultats obtinguts des de dues perspectives: d’una conducció estàndard i una d’esportiva

Comunicação oral com pacientes hematológicos: comportamentos facilitadores e bloqueadores

Neste estudo descritivo, adotamos o modelo de FORREST (1983) para categorização das emissões orais dos elementos da equipe de enfermagem ao prestarem assistência a pacientes hematológicos com alterações oncológicas. Buscando identificar a freqüência das categorias facilitadoras(F) e bloqueadoras(B) da comunicação, bem como de suas subcategorias, observamos, com o registro em vídeo, as interações entre 8 pacientes e 14 membros da equipe de Enfermagem de um Hospital Escola da cidade de Ribeirão Preto-SP. Registramos 8822 categorias sendo 56,9% facilitadoras(F). Dentre estas as mais freqüentes foram: dando informações (50,3%) clarificando (28,0%) e reconhecendo presença (11,2%). Das bloqueadoras(B), as mais frequentes foram: questões fechadas (64,6%), aconselhamento (13,9%) e aprovando ou concordando (10%). As demais subcategorias (F e B) obtiveram freqüências inferiores a 4,5%. Sugerimos maior emprego das outras categorias facilitadoras e, em situações especiais, o uso de questões fechadas. Acreditamos ser fundamental para o aprofundamento da relação equipe de enfermagem-pacientes a redução da subcategoria aconselhamento e aprovações da forma como vêm sendo empregados.

Primary motor cortex involvement in Alzheimer disease.

In Alzheimer disease (AD) the involvement of entorhinal cortex, hippocampus, and associative cortical areas is well established. Regarding the involvement of the primary motor cortex the reported data are contradictory. In order to determine whether the primary motor cortex is involved in AD, the brains of 29 autopsy cases were studied, including, 17 cases with severe cortical AD-type changes with definite diagnoses of AD, 7 age-matched cases with discrete to moderate cortical AD-type changes, and 5 control cases without any AD-type cortical changes. Morphometric analysis of the cortical surface occupied by senile plaques (SPs) on beta-amyloid-immunostained sections and quantitative analysis of neurofibrillary tangles (NFTs) on Gallyas-stained sections was performed in 5 different cortical areas including the primary motor cortex. The percentage of cortical surface occupied by SPs was similar in all cortical areas, without significant difference and corresponded to 16.7% in entorhinal cortex, 21.3% in frontal associative, 16% in parietal associative, and 15.8% in primary motor cortex. The number of NFTs in the entorhinal cortex was significantly higher (41 per 0.4 mm2), compared with those in other cortical areas (20.5 in frontal, 17.9 in parietal and 11.5 in the primary motor cortex). Our findings indicate that the primary motor cortex is significantly involved in AD and suggest the appearance of motor dysfunction in late and terminal stages of the disease.

A pesquisa em saúde infantil: a técnica do relato oral e o depoimento de mães

Os coeficientes de morbimortalidade infantil apontam alguns fatores aos quais determinados grupos considerados de risco estão expostos, mas não revelam as reais condições de sua qualidade de vida. O presente estudo tem por objetivo descrever os passos percorridos pelas autoras na construção de uma pesquisa qualitativa sobre o modo de vida materno, discutindo aspectos metodológicos referentes ao recorte do objeto e à coleta de dados, em particular, à utilização da técnica de relato oral e as vantagens e dificuldades que esta apresenta. A narrativa das mães possibilita conhecer as necessidades, preocupações e estratégias que elas utilizam para cuidar da saúde dos filhos, bem como, determinações sociais mais amplas de suas condições de existência. Desta forma, o conhecimento gerado é importante para a organização das políticas e práticas sociais desenvolvidas pelo setor saúde.

Natureza e gravidade das lesões em vítimas de acidente de trânsito de veículo a motor

Trata-se de um estudo retrospectivo que teve por objetivo caracterizar a natureza e gravidade da lesão de pacientes hospitalizados, vítimas de acidente de trânsito de veículo a motor através da Abbreviated Injury Scale (AIS). Foram analisadas 220 vítimas internadas em uma Instituição referência para trauma em São Paulo, Brasil. Do total de pacientes, 111 eram pedestres, 83 ocupantes de auto e 26 ocupantes de moto. As lesões mais frequentes localizaram se em membros/cintura pélvica e cabeça/pescoço para toda população do estudo com gravidade de lesão AIS £ 3. Faleceram 45 vítimas, sendo dois terços de pedestres.

Two cases of "cannabis acute psychosis" following the administration of oral cannabis.

BACKGROUND: Cannabis is the most commonly used illegal drug and its therapeutic aspects have a growing interest. Short-term psychotic reactions have been described but not clearly with synthetic oral THC, especially in occasional users. CASE PRESENTATIONS: We report two cases of healthy subjects who were occasional but regular cannabis users without psychiatric history who developed transient psychotic symptoms (depersonalization, paranoid feelings and derealisation) following oral administration of cannabis. In contrast to most other case reports where circumstances and blood concentrations are unknown, the two cases reported here happened under experimental conditions with all subjects negative for cannabis, opiates, amphetamines, cocaine, benzodiazepines and alcohol, and therefore the ingested dose, the time-events of effects on behavior and performance as well as the cannabinoid blood levels were documented. CONCLUSION: While the oral route of administration achieves only limited blood concentrations, significant psychotic reactions may occur.

História oral de vida: buscando o significado da hemodiálise para o paciente renal crônico

Este artigo tem como objetivo mostrar a utilização da história oral de vida como referencial metodológico para obtenção de dados qualitativos, buscando compreender o significado da hemodiálise e o impacto desta modalidade terapêutica na vida de pacientes do serviço de Hemodiálise do Hospital Universitário da Universidade de São Paulo.

Interregional compensatory mechanisms of motor functioning in progressing preclinical neurodegeneration.

Understanding brain reserve in preclinical stages of neurodegenerative disorders allows determination of which brain regions contribute to normal functioning despite accelerated neuronal loss. Besides the recruitment of additional regions, a reorganisation and shift of relevance between normally engaged regions are a suggested key mechanism. Thus, network analysis methods seem critical for investigation of changes in directed causal interactions between such candidate brain regions. To identify core compensatory regions, fifteen preclinical patients carrying the genetic mutation leading to Huntington's disease and twelve controls underwent fMRI scanning. They accomplished an auditory paced finger sequence tapping task, which challenged cognitive as well as executive aspects of motor functioning by varying speed and complexity of movements. To investigate causal interactions among brain regions a single Dynamic Causal Model (DCM) was constructed and fitted to the data from each subject. The DCM parameters were analysed using statistical methods to assess group differences in connectivity, and the relationship between connectivity patterns and predicted years to clinical onset was assessed in gene carriers. In preclinical patients, we found indications for neural reserve mechanisms predominantly driven by bilateral dorsal premotor cortex, which increasingly activated superior parietal cortices the closer individuals were to estimated clinical onset. This compensatory mechanism was restricted to complex movements characterised by high cognitive demand. Additionally, we identified task-induced connectivity changes in both groups of subjects towards pre- and caudal supplementary motor areas, which were linked to either faster or more complex task conditions. Interestingly, coupling of dorsal premotor cortex and supplementary motor area was more negative in controls compared to gene mutation carriers. Furthermore, changes in the connectivity pattern of gene carriers allowed prediction of the years to estimated disease onset in individuals. Our study characterises the connectivity pattern of core cortical regions maintaining motor function in relation to varying task demand. We identified connections of bilateral dorsal premotor cortex as critical for compensation as well as task-dependent recruitment of pre- and caudal supplementary motor area. The latter finding nicely mirrors a previously published general linear model-based analysis of the same data. Such knowledge about disease specific inter-regional effective connectivity may help identify foci for interventions based on transcranial magnetic stimulation designed to stimulate functioning and also to predict their impact on other regions in motor-associated networks.

Urinary analysis of four testosterone metabolites and pregnanediol by gas chromatography-combustion-isotope ratio mass spectrometry after oral administrations of testosterone.

The most frequently used method to demonstrate testosterone abuse is the determination of the testosterone and epitestosterone concentration ratio (T/E ratio) in urine. Nevertheless, it is known that factors other than testosterone administration may increase the T/E ratio. In the last years, the determination of the carbon isotope ratio has proven to be the most promising method to help discriminate between naturally elevated T/E ratios and those reflecting T use. In this paper, an excretion study following oral administration of 40 mg testosterone undecanoate initially and 13 h later is presented. Four testosterone metabolites (androsterone, etiocholanolone, 5 alpha-androstanediol, and 5 beta-androstanediol) together with an endogenous reference (5 beta-pregnanediol) were extracted from the urines and the delta(13)C/(12)C ratio of each compound was analyzed by gas chromatography-combustion-isotope ratio mass spectrometry. The results show similar maximum delta(13)C-value variations (parts per thousand difference of delta(13)C/(12)C ratio from the isotope ratio standard) for the T metabolites and concomitant changes of the T/E ratios after administration of the first and the second dose of T. Whereas the T/E ratios as well as the androsterone, etiocholanolone and 5 alpha-androstanediol delta(13)C-values returned to the baseline 15 h after the second T administration, a decrease of the 5 beta-androstanediol delta-values could be detected for over 40 h. This suggests that measurements of 5 beta-androstanediol delta-values allow the detection of a testosterone ingestion over a longer post-administration period than other T metabolites delta(13)C-values or than the usual T/E ratio approach.

Santé buccale: déterminants sociaux d'un terrain majeur des inégalités [Oral health: social determinants of a health inequality]

The oral health of disadvantaged social groups is worse at all the ages than that of the favored groups. If tooth decay prevalence decreases, this disease is still unequally distributed: 20% of the children, those with the weakest socio-economic statute (SES), concentrate 60% of the decays. Edentulism strikes significantly more people with weak SES. The inequalities of oral health reflect those of general health. Evidence of the inequalities in oral health is exposed even in the developed countries. Different models of intervention are presented: risk groups identification and targeting by specific programs; oral health community approach which includes socio-economic and public health measures aiming all the population; insurance approach to be combined with the preceding ones.