O Platonismo de Russell na metafísica e na matemática

Neste artigo, analiso o surgimento e a superação do Platonismo em B. Russell, tanto na sua filosofia da matemática como na sua metafísica. Começo por explicitar os argumentos que levaram Russell a aderir ao chamado "Platonismo Proposicional" - posição que será tecnicamente relevante na definição de números. Na seção seguinte, discutirei até que ponto a teoria das descrições definidas determina, necessariamente, uma adesão ao nominalismo, e as dificuldades que surgem para o logicismo conseqüentes do abandono do platonismo. Finalmente, mostrarei como a posição madura de Russell caracteriza-se mais como um reducionismo do que propriamente como um nominalismo, e como este é fundado no princípio do mínimo vocabulário.

Memory as acquaintance with the past: some Lessons from Russell, 1912-1914

Russell's theory of memory as acquaintance with the past seems to square uneasily with his definition of acquaintance as the converse of the relation of presentation of an object to a subject. We show how the two views can be made to cohere under a suitable construal of 'presentation', which has the additional appeal of bringing Russell's theory of memory closer to contemporary views on direct reference and object-dependent thinking than is usually acknowledged. The drawback is that memory as acquaintance with the past falls short of fulfilling Russell's requirement that knowledge by acquaintance be discriminating knowledge - a shortcoming shared by contemporary externalist accounts of knowledge from memory.

Experiências em cenários temáticos de serviços

Este artigo pretende ampliar a compreensão sobre as experiências dos consumidores com os ambientes físicos oferecidos pelas empresas de serviços. Propõe-se, para tanto, a atualização de um modelo originário da teoria de Psicologia Ambiental, capaz de examinar a interação vivencial dos clientes com os cenários em que a empresa realiza a entrega do serviço. Para ilustrar o framework de Mehrabian-Russell, oferecem-se como exemplos situações nas quais os estímulos luminosos constituem o fulcro da interação entre clientes e cenários. Revigorando-se o entendimento dos ambientes a partir da integração entre o fenômeno de serviços e a própria existência humana, discutem-se os espaços temáticos como alternativas congruentes com as vivências perceptuais dos clientes nas “horas da verdade”. Nesse contexto, ao se abordar a noção pósmodernista de arquitetura mercadológica, abrem-se novas oportunidades de aproveitamento dos recursos de iluminação ambiental e teatro de serviços.

Echocardiographic Abnormalities and Antiphospholipid Antibodies in Patients with Systemic Lupus Erythematosus

OBJECTIVE: Lupus anticoagulant and anticardiolipin antibodies (aCL) have been associated with thrombosis, recurrent abortion, and thrombocytopenia in patients with systemic lupus erythematosus (SLE), but their relationship with cardiac disease is less clear. The purpose of this study was to evaluate the association between antiphospholipid antibodies (aPL) and echocardiographic abnormalities in patients with SLE. METHODS: A total of 70 consecutive patients and 42 control subjects underwent M-mode, 2-dimensional and Doppler echocardiography and tests for lupus anticoagulant, aCL IgG, IgM, and IgA. Lupus anticoagulant was assayed with the dilute Russell viper venom time, and aCL IgG, IgM, and IgA were measured by an enzyme-linked immunosorbent assay (ELISA). RESULTS: Lupus anticoagulant showed a prevalence of 10%. As a whole, aCL had a prevalence of 44.3% and aPL had a prevalence of 50%. Patients with echocardiographic abnormalities had a prevalence of 54.3% and showed a trend towards an association with aCL IgG (P=0.06). The presence of pulmonary hypertension (PH) was significantly associated with aCL IgG (p=0.02). CONCLUSION: aCL IgG was significantly associated with PH and showed a strong trend towards an association with echocardiographic abnormalities taken together. These findings suggest a role for aCL IgG in the development of lupus cardiovascular disease.

Panencefalite subaguda esclerosante: correlação entre aspectos imunológicos e histopatológicos

Foi realizado um estudo clínico, laboratorial, eletroencefalográfico, sorológico e virológico em 4 pacientes com o diagnóstico clínico de "panencefalite subaguda esclerosante". Em todos constatou-se uma elevada concentração de anticorpos contra sarampo, tanto no líquido céfalo-raquidiano como no soro sangüíneo, sendo que em 3 pacientes a concentração de anticorpos era mais elevada no líquido céfalo-raquidiano. Em dois destes pacientes foram feitas biópsias cerebrais, que evidenciaram um processo meningo-encefalítico crônico, com focos de neuroniofagia esparsos e infiltrados inflamatórios perivasculares de natureza linfoplasmocitária. Ao mesmo tempo fez-se uma revisão de 18 casos desta enfermidade, já publicados, agora no sentido de estudar mais detidamente a natureza da infiltração inflamatória meníngea e perivascular. O aspecto histopatológico resumia-se em infiltração linfoplasmocitária meníngea esparsa, contrastando com densos infiltrados inflamatórios perivasculares também linfoplasmocitários, muitas vezes com grande riqueza em "corpos de Russell". Em vista destes achados sugere-se a possibilidade de que os anticorpos contra sarampo, encontrados em elevada concentração no líquido céfalo-raquidiano destes pacientes, sejam produzidos nos infiltrados perivasculares do próprio tecido nervoso.

Plasmodium coatneyi-infected rhesus monkeys: a primate modelfor human cerebral malaria

Although several animal models for human cerebral malaria have been proposed in the past, name have shown pathological findings that are similar to those seen in humans. In order to develop an animal model for human cerebral malaria, we studied the pathology of brains of Plasmodium coatneyi (primate malaria parasite)-infected rhesus monkeys. Our study demonstrated parazitized erythrocyte (PRBC) sequestration and cytoadherence of knobs on PRBC to endothelial cells in cerebral microvessels of these monkeys. This similar to the findings een in human cerebral malaria. Crebral microvessels with sequestred PRBC were shown by immunohistochemistry to possess CD36, TSP and ICAM-1. These proteins were not evident in cerebral microvessels of uninfected control monkeys. Our study indicates, for the first time, that rhesus monkeys infected with P. coatneyi can be used as a primate model to study human cerebral malaria.

The consequences of malaria infection in pregnant women and their infants

Preliminary results are presented from this study which indicate that 84.8 of pregnant women present at first antenatal visit with anemia (Hb 11g/dl) an 8.7 of their infants (n = 230) have a hemoglobin at birth below 14g/dl. There is an association between pregnancy anemia and malaria. A case control study in pregnant women and an infant cohort study to 18 months of age, are employed to study the cause and effects of anemia and malaria on women and their infants health.

Molecular characterisation of intermediate snail hosts and the search for resistance genes

The relationship between schistosomes and their intermediate hosts is an extremely intricate one with strains and species of the parasite depending on particular species of snail, which in turn may vary in their susceptibility to the parasites. In order to gain a better understanding of the epidemiology of the disease we have been investigating the use of molecular markers for snail identification and for studying host-parasite relationships. In this paper we will draw on examples concerning schistosomiasis in West and East Africa to illustrate how a molecular analysis can be used as part of a "total evidence" approach to characterisation of Bulinus species and provide insights into parasite transmission. Particular emphasis is given to ribosomal RNA genes (rRNA), random amplified polymorphic DNA (RAPDs) and the mitochondrial gene cytochrome oxidase I (COI). Snails resistant to infection occur naturally and there is a genetic basis for this resistance. In Biomphalaria glabrata resistance to Schistosoma mansoni is known to be a polygenic trait and we have initiated a preliminary search for snail genomic regions linked to, or involved in, resistance by using a RAPD based approach in conjunction with progeny pooling methods. We are currently characterising a variety of STSs (sequence tagged sites) associated with resistance. These can be used for local linkage and interval mapping to define genomic regions associated with the resistance trait. The development of such markers into simple dot-blot or specific PCR-based assays may have a direct and practical application for the identification of resistant snails in natural populations.

Temporal and spatial distribution of Leishmania mexicana infections in a population of Neotoma micropus

A 19-month mark-release-recapture study of Neotoma micropus with sequential screening for Leishmania mexicana was conducted in Bexar County, Texas, USA. The overall prevalence rate was 14.7% and the seasonal prevalence rates ranged from 3.8 to 26.7%. Nine incident cases were detected, giving an incidence rate of 15.5/100 rats/year. Follow-up of 101 individuals captured two or more times ranged from 14 to 462 days. Persistence of L. mexicana infections averaged 190 days and ranged from 104 to 379 days. Data on dispersal, density, dispersion, and weight are presented, and the role of N. micropus as a reservoir host for L. mexicana is discussed.