Preliminary study of Porcine circovirus type 2 and Torque teno sus virus coinfection frequencies in Brazilian pig herds

Torque teno sus virus (TTSuV) is emergent in swine herds. Recent studies have shown an increased frequency of TTSuV2 in Porcine circovirus type 2 (PCV2)-associated diseases (PCVAD), which are endemic in many swine-producing countries, including Brazil. Coinfection with several other viral and bacterial agents results in an increased incidence of more severe PCVAD. Given the limited information on TTSuV and PCV2 coinfection, especially in Brazilian swine herds, this study made a preliminary estimation of the occurrence of coinfection in swine herds by testing samples from different categories. Between 2008 and 2009, 111 samples of feces and 23 serum samples from 5 swine herds were tested for PCV2 and TTSuVs and the results analyzed for associations between these agents. No significant differences in coinfection frequency were observed for PCV2 1 + TTSuV1 or for PCV2 1 TTSuV2 between nursery piglets (P = 0.730), growing pigs (P = 0.331), or sows (P = 0.472). However, a significant difference was observed for PCV2 1 TTSuV1 1 TTSuV2 between nursery piglets and growing pigs (P = 0.004; Fisher's exact test). Phylogenetic studies agreed with the grouping of TTSuV1 and TTSuV2 into 2 different clades, with no distinct pattern of clustering of these isolates with the animal categories.

DRIVING AND RESTRICTIVE FACTORS IN THE PROCESS OF KNOWLEDGE CREATION: A COMPARATIVE CASE STUDY IN BRAZILIAN TECHNOLOGY-BASED ENTERPRISES

The article aims to analyze the process of knowledge creation in Brazilian technology-based companies, using as a background the driving and restrictive factors found in this process. As the pillars of discussion, four main modes of knowledge conversion were used, according to the Japanese model: socialization, externalization, combination and internalization. The comparative case method through qualitative research was carried out in nine technology-based enterprises that had been incubated or have recently passed through the stage of incubation (so-called graduated companies) in the Technology Park of Sao Carlos, state of Sao Paulo, Brazil. Among the main results, the combination of knowledge was identified as more conscious and structured in graduated companies, in relation to incubated companies. In contrast, it was noted that incubated companies have an environment with greater opportunities for socialization, internalization and externalization of knowledge.