50 resultados para Greek History


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The effect of exposing the lymnaeid snail Fossaria cubensis to the trematode Fasciola hepatica on the snail population's life-history traits was studied under laboratory conditions. Exposed individuals showed a lower survival rate than control snails, although from week 7 onward a slower decrease of this parameter in relation to the control group was observed. There were higher values of fecundity rate for the controls compared to the exposed group except during weeks 9, 10, 11 and 12, which was the time that followed the period when almost all of the infected snails died. Both the intrinsic and finite rates of natural increase were significantly higher for the control group, but exposed snails still attained a lower mean generation time. Age-specific trade-offs were found, mainly for the weekly increase in size versus the number of eggs per mass, the weekly increase in size versus the number of viable eggs per mass, the number of masses versus the hatching probability and the number of eggs versus the hatching probability. All these negative associations were significant for juveniles of both control and exposed snails and not for adults; however, exposed young individuals exhibited much higher values of the correlation coefficient than control animals.

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A population of Pseudosuccinea columella was raised under laboratory conditions and its life tables were determined in isolated and paired snails. Isolated snails were significantly larger in shell size than paired snails from five weeks of age onward. Also, statistically significant differences were found for the number of eggs per mass per individual from week 5 to 9, isolated snails exhibiting the highest values. The intrinsic and finite rates of increase were greater in isolated than in paired snails. Either an inhibition of the reproductive output between individuals or the advantage of selfing may be the cause of the differences in this species, acting as a possible mechanism that increase the fitness of isolated snails.

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The life history of the trematode Pygidiopsis macrostomum Travassos, 1928 is described for the first time. Rediae and cercariae were obtained from naturally infected snails Heleobia australis (d´Orbigny), a new first intermediate host. Metacercariae were found encysted in the mesenteries of three naturally infected guppies, Phalloptychus januarius (Hensel), Jenynsia multidentata (Jenyns) (new host records) and Poecilia vivipara Bloch and Schneider. Experimental infections were successfully completed in the intermediate hosts H. australis and Poe. vivipara reared in the laboratory and hamsters Mesocricetus auratus Waterhouse were utilised as a definitive host.

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The evolution of knowledge regarding ocular toxoplasmosis over the last 30 years is described based on studies and observations performed in Southern Brazil. The isolation ofToxoplasma gondii established the definitive diagnosis of the disease. It was proven that in most cases, the disease was acquired after birth, a concept supported by the description of numerous familial cases and observation of the disease many years after primary infection. Epidemiological studies showed important regional variations in the prevalence of the disease due to different factors, including the types of strains involved, of which type I predominates. The large number of patients also enabled detailed study of the different forms of clinical presentation of the disease and its complications. New parameters have been established for the use of steroids and the management of pregnant women with active lesions. Studies on the epidemiology of toxoplasmic infection in pregnant women and newborns showed a high prevalence of infection. The different factors of exposure to infection have also been studied. Gradually, preventive actions have been developed in the sphere of public health, although they have not been sufficiently effective. Trends for future research over the next few years are also outlined.

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Mutations in the Pfcrt gene that change the resulting amino acids and form different haplotypes are common and correlate with the prevalence of chloroquine resistant (CQR) field isolates of the malaria parasite, Plasmodium falciparum. This correlation provides opportunities to infer the global evolutionary history of CQ resistance by analysing CQR Pfcrt haplotype data. We collated data on the Pfcrt haplotypes from different global studies and performed evolutionary genetic analysis to present comprehensive and comparative information on the global distribution of five major CQR-Pfcrt haplotypes and evolutionary inter-relationships among 38 different countries. Using the haplotype diversity data, inter-continental genetic differentiation was also ascertained.

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The adaptation of insect vectors of human diseases to breed in human habitats (domestication) is one of the most important phenomena in medical entomology. Considerable data are available on the vector mosquito Aedes aegypti in this regard and here we integrate the available information including genetics, behaviour, morphology, ecology and biogeography of the mosquito, with human history. We emphasise the tremendous amount of variation possessed by Ae. aegypti for virtually all traits considered. Typological thinking needs to be abandoned to reach a realistic and comprehensive understanding of this important vector of yellow fever, dengue and Chikungunya.

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Chagas disease is maintained in nature through the interchange of three cycles: the wild, peridomestic and domestic cycles. The wild cycle, which is enzootic, has existed for millions of years maintained between triatomines and wild mammals. Human infection was only detected in mummies from 4,000-9,000 years ago, before the discovery of the disease by Carlos Chagas in 1909. With the beginning of deforestation in the Americas, two-three centuries ago for the expansion of agriculture and livestock rearing, wild mammals, which had been the food source for triatomines, were removed and new food sources started to appear in peridomestic areas: chicken coops, corrals and pigsties. Some accidental human cases could also have occurred prior to the triatomines in peridomestic areas. Thus, triatomines progressively penetrated households and formed the domestic cycle of Chagas disease. A new epidemiological, economic and social problem has been created through the globalisation of Chagas disease, due to legal and illegal migration of individuals infected by Trypanosoma cruzi or presenting Chagas disease in its varied clinical forms, from endemic countries in Latin America to non-endemic countries in North America, Europe, Asia and Oceania, particularly to the United States of America and Spain. The main objective of the present paper was to present a general view of the interchanges between the wild, peridomestic and domestic cycles of the disease, the development of T. cruzi among triatomine, their domiciliation and control initiatives, the characteristics of the disease in countries in the Americas and the problem of migration to non-endemic countries.

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ABSTRACT Objective To explore potential associations between nursing workload and professional satisfaction among nursing personnel (NP) in Greek Coronary Care Units (CCUs). Method A cross-sectional study was performed involving 66 members of the NP employed in 6 randomly selected Greek CCUs. Job satisfaction was assessed by the IWS and nursing workload by NAS, CNIS and TISS-28. Results The response rate was 77.6%. The reliability of the IWS was α=0.78 and the mean score 10.7 (±2.1, scale range: 0.5-39.7). The most highly valued component of satisfaction was “Pay”, followed by “Task requirements”, “Interaction”, “Professional status”, “Organizational policies” and “Autonomy”. NAS, CNIS and TISS-28 were negatively correlated (p≤0.04) with the following work components: “Autonomy”, “Professional status”, “Interaction” and “Task requirements”. Night shift work independently predicted the score of IWS. Conclusion The findings show low levels of job satisfaction, which are related with nursing workload and influenced by rotating shifts.

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In the present work the natural history and immature stages of Gonioterma exquisita Duckworth, 1964 of the Brazilian cerrado region are described. The caterpillars are external folivorous feeders and present a diet restricted to pubescent-leaved host plants of the genus Byrsonima Rich. (Malpighiaceae). They are solitary caterpillars and they build a hard individual shelter that looks like a planorbid shell, made from silk and frass, covered with trichomes and silk, where they develop until the last larval instar on the host plant, and remain inside it until the adult emergence on herbaceous stratum. The larval development presented eight instars. Egg, larval head capsules, instar duration, pupa, shelter, and behavior are also described. Diapause is mentioned for the first time in this species.

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New records for species of Theope (Lepidoptera, Riodinidae) for the state of Pernambuco and northeastern Brazil, with notes on their natural history. Five new records for the state of Pernambuco and one new record for NE-Brazil are reported in this paper for the genus Theope. Relationship between ants and T. terambus was observed for the first time which also consists on the first ever recorded myrmecophilous interaction between Pheidole ants and a Theope immature. Schoepfia guianensis is reported as a probable hostplant for T. terambus. Illustrations of seven species of Theope which occur in the northeastern Atlantic Rainforest are provided.

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Essays on the history of Brazilian dipterology. I. The first notices about Brazilian Diptera (16th century). This paper presents a historical resume of the first notices about Brazilian Diptera during the 16th century, given by Francisco Pires in 1552 (the oldest mention known), José de Anchieta, Leonardo do Valle, Pero de Magalhães de Gandavo, Jean de Léry and Gabriel Soares de Souza, ending with Fernão Cardim, who made the last mentions of Brazilian Diptera in that century.