Isolamento e estudo experimental de duas novas culturas de bacilos ácido-alcool resistentes de muco nasal de leprosos

The A. described on December 14, 1951, his first culture of acid-fast bacillus isolated from nasal mucus of a leprous girl. in this paper the A. describes two new strains of acid-fast bacilli gotten also from nasal mucus of other two leprous girls, L3 cases. The first patient (layse S) had her mucus treated by petroff's method on December 16, 1952 and sown onto three tubes of loewenstein medium and in glycerin broth. After two weeks incubation at 37°C all three tubes of Loewenstein showed many punctiforme and pin-head yellowish colonies, whose microscopic examination proved to be of a pure acid-fast bacillus culture. This sample inoculated in rats and mice produced, after 55 days incubation, small tumors from which the culture was easily recovered. On April, 9, 1953 a new sample of nasal mucus of the same patient was sown in three tubes of Loewenstein. After two weeks incubation at 37°C all 3 tubes showed germination of small yellowish colonies of acid-fast bacilli. Within four months being gotten two samples of identical cultures in all smeared tubes of Loewenstein medium sown, proved that such cultures were not an ordinary ambient contamination. Second patient: - Maria N. After various sowing of different kinds of material from her, february 26, 1953 her nasal mucus treated by soda and sown onto Loewenstein medium, after 25 days incubation showed in only one tube, one small round colony, at first white, becoming creamy after three months. Transplants in various media grew at first slowly and after 2 or 3 generations grew faster. The "Layse" strain produced pellicle in glycerin broth and Dubos medium; the "Maria N." strain did not produce as yet. Both strains (Layse I and II, and Maria N.) gave weak positive Dubos test in half-an-hour and negative after 24 hours reading. Both were strongly positive when stained by Gram, Ziehl-Neelsen and Fontes methods. Both strains gave also positive fluoroscopy. These cultures are being studied. The A. concludes that, according to his experience, the slower growing cultures of acid-fast bacilli isolated from leprosy material, are the more suitable for experimental work. Aknowledgement. The A. thanks to Miss MARIA DE LOURDES SANTANA for her valuable collaboration in the studies of the described cultures.

Can genetic algorithms explain experimental anomalies? An application to common property resources

It is common to find in experimental data persistent oscillations in the aggregate outcomes and high levels of heterogeneity in individual behavior. Furthermore, it is not unusual to find significant deviations from aggregate Nash equilibrium predictions. In this paper, we employ an evolutionary model with boundedly rational agents to explain these findings. We use data from common property resource experiments (Casari and Plott, 2003). Instead of positing individual-specific utility functions, we model decision makers as selfish and identical. Agent interaction is simulated using an individual learning genetic algorithm, where agents have constraints in their working memory, a limited ability to maximize, and experiment with new strategies. We show that the model replicates most of the patterns that can be found in common property resource experiments.

The effect of candidate quality on electoral equilibrium: an experimental study

When two candidates of different quality compete in a one dimensional policy space, the equilibrium outcomes are asymmetric and do not correspond to the median. There are three main effects. First, the better candidate adopts more centrist policies than the worse candidate. Second, the equilibrium is statistical, in the sense that it predicts a probability distribution of outcomes rather than a single degenerate outcome. Third, the equilibrium varies systematically with the level of uncertainty about the location of the median voter. We test these three predictions using laboratory experiments, and find strong support for all three. We also observe some biases and show that they canbe explained by quantal response equilibrium.

Do market conditions affect gift exchange? Evidence from experimental markets with excess supply and excess demand

We study whether people's behavior in unbalanced gift exchange markets with repeated interaction are affected by whether they are on the excess supply side or the excess demand side of the market. Our analysis is based on the comparison of behavior between two types of experimental gift exchange markets, which vary only with respect to whether first or second movers are on the long side of the market. The direction of market imbalance could influence subjects' behavior, as second movers (workers) might react differently to favorable actions by first movers (firms) in the two cases. While our data show strong deviations from the standard game-theoretic prediction, we find mainly secondary treatment effects. Wage offers are not higher when there is an excess supply of firms, and workers do not respond more favorably to a given wage when there is an excess supply of labor. The state of competition does not appear to have strong effects in our data. We also present data from single-period sessions that show substantial gift exchange even without repeated interactions.

Asymmetric demand information in uniform and discriminatory call auctions: an experimental analysis motivated by electricity markets

We study the outcomes of experimental multi-unit uniform and discriminatory auctions with demand uncertainty. Our study is motivated by the ongoing debate about market design in the electricity industry. Our main aim is to compare the effect of asymmetric demand-information between sellers on the performance of the two auction institutions. In our baseline conditions all sellers have the same information, whereas in our treatment conditions some sellers have better information than others. In both information conditions we find that average transaction prices and price volatility are not significantly different under the two auction institutions. However, when there is asymmetric information among sellers the discriminatory auction is significantly less efficient. These results are not in line with the typical arguments made in favor of discriminatory pricing in electricity industries; namely, lower consumer prices and less price volatility. Moreover, our results provide some indication that discriminatory auctions reduce technical efficiency relative to uniform auctions.

El Taller de traducción como metodología didáctica experimental en un marco epistemológico socioconstructivista y humanista

Aquest treball de recerca presenta les diferents fases d’un experiment pilot que vaig projectar i realitzar dins l’àmbit de l’ensenyament de la traducció a un context universitari. L’experiment va consistir en l’aplicació i observació d’una metodologia didàctica innovadora, amb una base epistemològica socioconstructivista i humanista, i en l’avaluació dels resultats obtinguts. Per l’experiment pilot vaig seleccionar com a marc teòric el model socioconstructivista del procés d’ensenyament i aprenentatge proposat per Williams i Burden (1997), que integra instàncies constructivistes, interaccionistes i humanistes. En aquest àmbit vaig elaborar una metodologia didàctica innovadora, el “Taller de Traducció”, modelat sobre el Constructivist Workshop proposat per Don Kiraly (2000: 62-64) al qual vaig aportar algunes modificacions per adequar-lo al context diferent d’ensenyament. El disseny experimental basat en la utilització d’un grup experimental i d’un de control, preveu el recurs a instruments de recollida de dades qualitatives i quantitatives. Les hipòtesis elaborades prospecten l’aparició de determinats efectes com a conseqüència de l’aplicació del tractament experimental (autonomia, motivació i presa de consciència) i, al mateix temps es basen en la pressuposició, sustentat sobre la literatura consultada, que els efectes prospectats milloren el procés d’ensenyament i aprenentatge. Per tant, vaig intentar, per una banda, verificar l’eficàcia del tractament relacionada amb l’aparició dels efectes prospectats i, per una altra, mesurar l’incidència d’aquests efectes sobre el procés d’ensenyament i aprenentatge. A més, vaig dur a terme l’observació i avaluació de la metodologia aplicada respecte la coherència amb les bases epistemològiques socioconstructivistes i a la funcionalitat dins el context universitari on es va aplicar. Totes les dades recollides confirmen la coherència i la funcionalitat de la metodologia aplicada, tant pel que fa a l’eficàcia relacionada amb l’aparició dels efectes prospectats a les hipòtesis elaborades i a la seva incidència sobre la millora del procés d’ensenyament i aprenentatge, tot i que es van detectar algunes fallides a l’experiment pilot que se solucionaran a l’experiment definitiu. Els resultats positius de l’experiment pilot han estat confirmades també per les dades d’altres dos experiments realitzats posteriorment amb altres grups d’estudiants de la mateixa assignatura. Tots els resultats recollits es faran servir per projectar l’experiment definitiu, aportant-hi les modificacions necessàries per eliminar les fallides evidenciades durant la fase d’aplicació de l’experiment pilot i de les seves extensions i seguiments, i serviran com a base per a la meva tesi doctoral a la qual voldria arribar a formular una proposta socioconstrucitivista i humanista integradora per a l’ensenyament de la traducció.

Hiperglicemia na intoxicação escorpiônica experimental em cão

The production of hyperglycemia during the acute phase of scorpion poisoning produced by T. bahiensis in dogs is confirmed now. The highest degree on average, was reached 10 minutes after the injection of venom. In our hands, the previous bilateral adrenalectomy did not avoid the hyperglycemia. The average of the blood sugar level has been similar to that observed in dogs with adrenal glands, the highest blood sugar level was also registered after 10 minutes. The hyperglycemia obtained in adrenolectomized dogs is, probably, due to the liberation of Sympatin (Nor-adrenalin and adrenalin) as a consequence of the central excitation by the poison on the hepatic nerves and other ganglionar terminations of the Sympathetic Nervous System. Our present researches suggest that the venom has adrenergic action besides the central action.

Experimental Time Study (Rome)

Combined media on photographic paper. 76" x 40"

Political autonomy and independence: theory and experimental evidence

We study the process by which subordinated regions of a country can obtain a more favourable political status. In our theoretical model a dominant and a dominated region first interact through a voting process that can lead to different degrees of autonomy. If this process fails then both regions engage in a costly political conflict which can only lead to the maintenance of the initial subordination of the region in question or to its complete independence. In the subgame-perfect equilibrium the voting process always leads to an intermediate arrangement acceptable for both parts. Hence, the costly political struggle never occurs. In contrast, in our experiments we observe a large amount of fighting involving high material losses, even in a case in which the possibilities for an arrangement without conflict are very salient. In our experimental environment intermediate solutions are feasible and stable, but purely emotional elements prevent them from being reached.

Personal relations and their effect on behavior in an organizational setting: an experimental study

We study how personal relations affect performance in organizations. In the experimental game we use a manager has to assign different degrees of decision power to two employees. These two employees then have to make distributive decisions which affect themselves and the manager. Our focus is on the effects on managers' assignment of decision power and on employees' distributive decisions of one of the employees and the manager knowing each other personally. Our evidence shows that managers tend to favor employees that they personally know and that these employees tend, more than other employees, to favor the manager in their distributive decisions. However, this behavior does not affect the performance of the employees that do not know the manager. All these effects are independent of whether the employees that know the manager are more or less productive than those who do not know the manager. The results shed light on discrimination and nepotism and its consequences for the performance of family firms and other organizations.

Aspectos histopatológicos da encefalite aguda toxoplásmica: (humana e experimental)

Realizaram os Autores um estudo histopatológico de dois casos de encefalite aguda toxoplásmica humana mostrando a distribuição dos acúmulos inflamatórios, nitidamente em relação com rêde vascular, a composição celular dêstes acúmulos e a sua histogênese. Os resultados são discutidos e comparados com material experimental de coelhos.

Implantação intracerebral experimental de sarcomas

Estudo histopatológico da implantação intracerebral de sarcomas, realizado em ratos (fibrosarcoma) e em camundongos (sarcoma 180). A implantação intracerebral de fibrosarcoma desenvolveu, em cerca de 45 dias, neoplasia relativamente bem delimitada, com pequena infiltração do parênquima nervoso adjacente, nunca se propagando a maiores distãncias devido a forte coesão entre as suas células, com grande diferenciação de fibrilas reticulares e de colágeno. Ao contrário, a inoculação do sarcoma 180, principalmente sob a forma ascítica, levou rapidamente a um quadro de forte hipertensão intracraniana, com disseminação das células neoplásticas pelos espaços subaracnoideanos e intraventriculares. Ambas as neoplasias propagavam-se pelos espaços subaracnoideanos e intraventriculares. Ambas as neoplasias propagavam-se pelos espaços perivasculares, porém o faziam de maneira diversa; o sarcoma 180 tinha uma disseminação muito intensa e rápida, que se fazia a longas distâncias, enquanto que o fibrossarcoma somente se disseminava nos vasos próximos à neoplasia em desenvolvimento. Tomando por base observações próprias e outras colhidas na bibliografia especializada, conclui-se que os agentes etiológicos destes tumores exercem sua ação sobre tipos celulares diferentes.

BUSP: um fibrosarcoma experimental de crescimento lento: nota prévia

Após ter-se verificado que a buclizina era capaz de acelerar o crescimento de tumor maligno até 33%, animais de laboratório foram tratados com essa substância em doses subletais agudas e muito acima das doses terapêuticas, por vias subcutâneas e intraperitoneal, ocorrendo, ocasionalmente, o aparecimento de fibrosarcomas nos ratos Wistar e sarcoma indiferenciado e adenoma papilífero em camundongos Swiss. O primeiro tumor surguiu em 1970, ao qual foi dada a sigla "BUSP" (BUclizina-SPoladore). O tumor vem sendo mantido com facilidade, apresentando como características: crescimento lento, permitindo uma sobrevida do animal em torno de três meses; peso em torno de cento e vinte e cinco gramas na fase final; intensa hiperemia peritumoral; tumor maciço, quase sem necrose na parte central; persistindo bastante livre entre a pele e os tecidos subjacentes, durante toda a evolução.

Desnutrição experimental: resultados anátomo-patológicos e bioquímicos da administração de dietas hipoprotéicas a ratos albinos jovens

Na tentativa de reproduzir experimentalmente os achados morfológicos e eletroforéticos (proteínas no soro) observados na desnutrição infantil, dois grupos de experiências foram realizados em ratos albinos jovens, submetendo-os a uma dieta pobre em proteínas (2%) por períodos de 41 a 88 dias. O modelo experimental reproduz em linhas gerais os principais danos estruturais vistos na patologia humana, ficando num meio termo entre kwashiorkor e marasmo. Alterações atróficas tegumentares foram assinaladas como achado tardio. O achado mais conspícuo foi metamorfose gordurosa hepática do tipo perilobular. A regeneração hepatocelular foi abortiva, aparecendo nos estágios finais das experiências ao lado dos fenômenos regressivos. Foi possível estabelecer seqüência lesional nas alterações estruturais do pâncreas, desde mofificações da quantidade de grânulos de zimogênio nos estágios iniciais até a atrofia acinosa acentuada, subvertendo a arquitetura do órgão, nos estágios finais. As alterações intestinais culminaram com o quadro de atrofia, não comparável em intensidade com a patologia humana, correspondem à diminuição da altura do epitélio mucoso, hipocelularidade da lâmina própria, criptas pequenas, pobreza em mitoses, que encurtam as vilosidades, assemelhando-se ao padrão mucoso dos chamados animais "germ-free". Além disso, os autores chamam a atenção para a intensa dimuição das célular muco-secretoras ao nível do epitélio do intestino delgado e grosso. No modelo surpreende-se também uma depleção linfo-histiocitária, representada por atrofia das placas de Peyer, diminuição das célular de Kupffer, atrofia do timo e depleção linfóide ganglionar e esplênica. O estudo bioquímico do soro revelou baixa das proteínas totais e do colesterol. A eletroforese de proteínas demonstrou acentuada baixa da fração albumina, com inversão A/G. Entre as globulinas, as frações alfa1 e alfa2 estão aumentadas no grupo desenutrido. Estes achados podem ser atribuídos à carência protéica, porquanto os controles utilizados, mesmo aqueles com restrição calórica, não apresentaram alterações histológicas ou hipoalouminemia.