2 resultados para Tyler, Bennet, 1783-1858.

em Repositório Científico da Universidade de Évora - Portugal


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The occurrence of Bursaphelenchus species in the Czech Republic is poorly known, the first report of the genus being made by Kubátová et al. (2000) who reported the association of B. eremus with the hyphomycetous microfungus, Esteya vermicola, and the bark beetle, Scolytus intricatus, collected from Quercus robur, in central Bohemia. To date, four other species have been reported from the country, namely B. fungivorus (Braasch et al., 2002), B. hofmanni (see Braasch, 2001), B. mucronatus (see Braasch, 2001) and B. vallesianus (Gaar et al., 2006). More recently, a survey for Bursaphelenchus species associated with bark- and wood-boring insects in the Czech Republic identified B. pinophilus Brzeski & Baujard, 1997 from the Moravia region. Although this represents a new country record, it was also associated with nematangia on the hind wings of a new insect vector. A total of 404 bark- and wood-boring insects were collected from declining or symptomatic trees and screened for the presence of Bursaphelenchus. Bark and longhorn beetles were captured manually after debarking parts of the trunk displaying symptoms of insect attacks. Longhorn beetle larvae were also collected together with logs cut from the trunk. Logs were kept at room temperature in the laboratory until insect emergence. Each adult insect was individually dissected in water and examined for nematodes. All nematodes resembling dauer juveniles of Bursaphelenchus were collected and identified by molecular characterisation using a region of ribosomal DNA (rDNA) containing the internal transcribed spacer regions ITS1 and ITS2. ITS-RFLP analyses using five restriction enzymes (AluI, HaeIII, HinfI, MspI, RsaI) were performed to generate the species-specific profile according to Burgermeister et al. (2009). Species identification was also confirmed by morphological data after culture of the dauers on Botrytis cinerea Pers. ex Ft., growing in 5% malt extract agar. During this survey, only species belonging to the Curculionidae, subfamily Scolytinae, revealed the presence of nematodes belonging to Bursaphelenchus. Dauers of this genus were found aggregated under the elytra in nematangia formed at the root of the hind wings (Fig. 1). The dauers were identified from 12 individuals of Pityogenes bidentatus (Herbst, 1783) (Coleoptera: Scolytinae) collected under the bark of Pinus sylvestris trunks. Each insect carried ca 10-100 dauers. The ITS-RFLP patterns of the dauers so obtained confirmed the identification of B. pinophilus associated with this insect species. Bursaphelenchus pinophilus has been found mainly in Europe and has been reported from various countries such as Poland (Brzeski & Baujard, 1997), Germany (Braasch, 2001), and Portugal (Penas et al., 2007). The recent detection of this species associated with dead P. koraiensis in Korea (Han et al., 2009) expands its geographical distribution and potential importance. It has been found associated only with Pinus species, but very little is known about the insect vector. The bark beetle, Hylurgus ligniperda, was initially suggested as the insect vector by Pe-nas et al. (2006), although the nematode associated with this insect was later reclassified as B. sexdentati by morphological and molecular analysis (Penas et al., 2007). According to the literature, P. bidentatus has been cited as a vector of Ektaphelenchus sp. (Kakuliya, 1966) in Georgia, and an unidentified nematode species in Spain (Roberston et al., 2008). Interestingly, B. pinophilus was found in the nematangia formed at the root of the hind wings of P. bidentatus. Although this phenomenon is not so common in other Bursaphelenchus species, B. rufipennis has been found recently in such a structure on the hind wings of the insect Dendroctonus rufipennis (Kanzaki et al., 2008). Although other nematode species (e.g., Ektaphelenchus spp.) are frequently found associated within the same nematangia (see Kanzaki et al., 2008), in this particular case, only dauers of B. pinophilus were identified. The association between B. pinophilus and P. bidentatus represents the first report of this biological association and the association with the Scolytinae strengthens the tight and specific links between this group of Bursaphelenchus species and members of the Scolytinae (Ryss et al., 2005).

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This chapter explores the relationship between environmental conflicts and technical progress, trying to understand, in the case of large mines of the Iberian Pyrite Belt, in Alentejo, how emerging environmental problems conditioned the performance or led to the search for alternative technical solutions, taking as chronological limit for this observation the beginning of World War II. In the absence of the archives of the companies, the research was based on existing administrative documents in the state archives (mining engineers reports, the licensing of mining activities), on reports and documents published in specialized mining press, in particular, the Bulletin of the Ministry of Public Works, Trade and Industry, the Journal of Public Works, Trade and Industry (both in Portuguese), and finally in the local press. Despite that limitation, the information available shows that in global competition markets, the success of the British enterprise in Santo Domingo had the active search for new technical solutions for the creation and adaptation of existing knowledge to local problems in order to maximize the mineral resources available. The early development of the hydrometallurgical processes for the treatment of poor ores, named ‘natural cementation’, can be explained as the way these companies tried to solve problems of competitiveness, boosting economies of scale. Thus, they transferred the environmental costs previously limited to agriculture to more fragile social groups, the poor fishermen of Guadiana River and of Vila Real de Santo António. Therefore, the hydrometallurgy of pyrites was developed locally, pioneered in Santo Domingo that allowed the survival and expansion of the British company from the late 1870s, that is, at a time when most small mines shut since they were not able to compete globally. Through different consented and regulated processes (judicial), through conflict or parliamentary mediation, the State imposed exceptionally additional costs to companies, either for compensation, the imposing the application of remediation measures to reduce the environmental damage in some cases, thus contributing to derail some projects. These cases suggest that the interaction between local conflicts, corporate behavior and technological progress proves to be complex. This article aims to contribute to the debate on economic and social history between the environment and technological progress, arguing that the fixed costs and economic imponderable social risks were factors that encouraged the companies to search for new solutions and to introduce innovations since that would allow the expansion of their activity. In this process the companies sometimes faced environmental dilemmas and unforeseen costs with consequences on the economy of firms. The nature of the knowledge needed to address the environmental problems they created, however, is of a very different nature from that knowledge needed to face the environmental burdens that were inherent to the development of its activity.