899 research outputs found

    Ecology and control of the trachoma vector Musca sorbens

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    The work described in this thesis was conducted In rural Gambia and builds a body of evidence Incriminating the fly Musca sorbens as a vector of the blinding disease, trachoma, which is caused by ocular infection with Chlamydia trachomatis. Literature on hygiene promotion, environmental change and flies and trachoma is reviewed in the context of the SAFE strategy for trachoma control advocated by the World Health Organization M. sorbens was present throughout the year in trachoma endemic communities; was responsible for the majority of fly-eye contacts; C. trachomatis DNA was found on it; and trachoma transmission dropped when they were removed from the environment. In a large cluster-randomised trial communities receiving fly control with insecticide for six months had a mean reduction in trachoma prevalence of 56% (95% Cl 19-93%; P=0.01) compared to controls and 37% (4-70%; P=0.068) fewer new prevalent cases of trachoma. Breeding media choice experiments showed that isolated human faeces were the preferred larval medium for M. sorbens and were capable of supporting the production of large numbers of adults. However, other animal faeces were also able to support M. sorbens development. This suggested that a community-based strategy to reduce the quantity of human faeces on the soil surface by providing latrines would have the effect of reducing the population of M. sorbens, and hence reduce fly-eye contact and trachoma transmission. The provision of latrines gave encouraging results, which were not statistically significant; 30% less active trachoma than controls after six months (-22-81%; P=0.210) and 28% (-5-60%; P=0.146) fewer new prevalent cases. Provision of latrines warrants further investigation as a method to control trachoma, particularly when used in conjunction with other control methods. The potential role of fly control in the SAFE strategy for trachoma control is discussed

    Improving angle stability by switching shunt reactors in mixed overhead cable lines. An Italian 400 kV case study

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    Stringent environmental constraints make the construction of new transmission overhead lines more and more difficult. Alternatively, today it is possible to use cable lines for high (HV) and extra-high (EHV) voltage systems. The configuration of the so-called mixed lines can create some problems in the operation of the electrical system, both during steady-state and transient conditions. In particular, the system stability is one of the main concerns when analyzing the dynamic response of power systems. In this paper, the study of angular stability of a system containing a mixed line is presented: a specific control logic applied to the shunt reactors of the mixed line is proposed as improvement of the overall system stability. The proposed switching logic is first discussed from a theoretical point of view and validated with two different testing systems. Then, the existing overhead-cable lines connecting Sicily to the rest of continental Europe 400 kV power system are taken as case study for the application of the proposed switching strategy. Several simulations are performed in the power system analysis software NEPLAN360: the results show the fundamental role of the timing of the control actions applied on the shunt reactors in helping the system to keep the stability. The proposed control proves to be an effective support to the system subjected to critical contingencies, contributing decisively to avoid the angular separation between areas and therefore to preserve the stability of the system

    Musca chamaeleon Linnaeus, 1758, spec. nov.

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    Musca chamaeleon [spec. nov.] M. antennis filatis clavatis, scutello bidentato luteo, abdomine nigro: fasciis lateralibus luteis. Swamm. metam. t. 4. bibl. t. 42. f. 2. Habitat Larva in Aquis dulcibus. Musca supra aquam obambulare solet.Published as part of Linnaeus, Carolus, 1758, Systema Naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis, Stockholm :Laurentius Salvius on page 589, DOI: 10.5962/bhl.title.542, http://zenodo.org/record/392220

    On the senior authorship of Musca oleae (Diptera: Tephritidae)

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    Pietro Rossi (1738–1804), Professor at the University of Pisa, in 1790 described the olive fruit fly Musca oleae in his opus Fauna Etrusca and for the next 121 years, Rossi was considered its author. During all the 900 century, Gmelin was considered the senior author. In this paper we report that the date of Rossi's Fauna Etrusca has been found to pre-date Gmelin's 13th Edition for the part that includes Musca oleae. Thus, we conclude that the senior author has to be considered definitively Rossi and not Gmelin

    Musca scripta Linnaeus, 1758, spec. nov.

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    Musca scripta [spec. nov.] M. antennis setariis nudiuscula, thorace lineis, scutello abdomineque lineari fasciis flavis. Fn. svec. 1091. Reaum. ins. 4. t. 10. f. 2, 3. Roes. ins. 2. musc. t. 6. Habitat inter Aphides, at Musca in floribus.Published as part of Linnaeus, Carolus, 1758, Systema Naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis, Stockholm :Laurentius Salvius on page 594, DOI: 10.5962/bhl.title.542, http://zenodo.org/record/392220

    Musca chamaeleon Linnaeus, 1758, spec. nov.

    No full text
    Musca chamaeleon [spec. nov.] M. antennis filatis clavatis, scutello bidentato luteo, abdomine nigro: fasciis lateralibus luteis. Swamm. metam. t. 4. bibl. t. 42. f. 2. Habitat Larva in Aquis dulcibus. Musca supra aquam obambulare solet.Published as part of Linnaeus, Carolus, 1758, Systema Naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis, Stockholm :Laurentius Salvius on page 589, DOI: 10.5962/bhl.title.542, http://zenodo.org/record/392220

    OAC Musca soybean

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    OAC Musca is a soybean (Glycine max (L.) Merr.) cultivar which is 3 d earlier than Hodgson and 2% higher in yield in Ontario trials. It has exhibited low field losses to Phytophthora megasperma f. sp. glycinea in Ontario testing, is a tall cultivar and is intended for use on clay soils. Key words: Soybean, cultivar description </jats:p

    Simulation-guided cardiac auscultation improves medical students' clinical skills: the Pavia pilot experience

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    Clinical evaluation is the cornerstone of any cardiac diagnosis, although excessive over-specialisation often leads students to disregard the value of clinical skills, and to overemphasize the approach to instrumental cardiac diagnosis. Time restraints, low availability of "typical" cardiac patients on whom to perform effective bedside teaching, patients' respect and the underscoring of the value of clinical skills all lead to a progressive decay in teaching. Simulation-guided cardiac auscultation may improve clinical training in medical students and residents. Harvey((c)) is a mannequin encompassing more than 50 cardiac diagnoses that was designed and developed at the University of Miami (Florida, USA). One of the advantages of Harvey((c)) simulation resides in the possibility of listening, comparing and discussing "real" murmurs. To objectively assess its teaching performance, the capability to identify five different cardiac diagnoses (atrial septal defect, normal young subject, mitral stenosis with tricuspid regurgitation, chronic mitral regurgitation, and pericarditis) out of more than 50 diagnostic possibilities was assessed in 523 III-year medical students (i.e. at the very beginning of their clinical experience), in 92 VI-year students, and in 42 residents before and after a formal 10-h teaching session with Harvey((c)). None of them had previously experienced simulation-based cardiac auscultation in addition to formal lecturing (all three groups) and bedside teaching (VI-year students and residents). In order to assess the "persistence" of the acquired knowledge over time, the test was repeated after 3 years in 85 students, who did not repeat the formal 10-h teaching session with Harvey((c)) after the III year. As expected, the overall response was poor in the "beginners" who correctly identified 11.0 % of the administered cardiac murmurs. After simulation-guided training, the ability to recognise the correct cardiac diagnoses was much better (72.0 %; p < 0.001 vs. baseline). Rather unexpectedly, before the tutorial, the performance of VI-year students and of residents was not significantly different from their III-year colleagues, since the two groups correctly identified 14.2 and 16.2 % of the diagnoses, respectively. After the tutorial, the VI-year students and the residents also improved their overall performance (to 73.1 and 76.1 %, respectively; p < 0.001 for both when compared to before the tutorial). The persistence of this capability after 3 years was remarkable, since the 85 students who repeated the test without any further exposure to the 10-h teaching session with Harvey((c)) correctly identified 68.4 % of the possible cardiac diagnoses (p < 0.001 vs. baseline). These data underscore the importance of clinical training in order to improve auscultation skills in our academic setting, prompting to redesign teaching curricula. Simulation-based cardiac auscultation should be considered as the "missing link" between formal lecturing and bedside teaching of heart sounds and murmurs
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