1,828 research outputs found

    Identifying human and animal faecal contamination in surface and drinking water : new concepts and approaches

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    Waterborne disease outbreaks caused by various pathogens have been reported from all over the world. They also play an important role in industrialized countries, despite good sanitation and high standards of hygiene. In Switzerland, waterborne disease outbreaks are uncommon but faecal contamination of springs occurs quite frequently in some areas. As a consequence, microbiological quality of drinking water is not constantly sufficient and there is potential for improvement. Based on the hygiene ordinance, cantonal authorities contribute with control actions to the supply of safe water to consumers. Microbiological quality assessment based on current drinking water guidelines do not discriminate between human and animal sources of contamination. However, methods for discriminating between human and animal faecal contamination are needed to identify sources of contamination and to provide specific scientific data as a basis for risk management measures and for the implementation of remedial interventions. The main goal of this thesis was to establish approaches for the identification of human and animal faecal contamination in surface and drinking water and to develop concepts for future investigations. A number of methods can be used to help identify sources of faecal contamination in water. The general concept is referred to as microbial source tracking (MST). Different methodologies for MST were previously used mainly for analysis of faecal samples and recreational waters such as streams, lakes and beaches. Prior to this study, MST was not applied in Switzerland. In the present thesis, source tracking approaches never before used in MST as well as methods previously described in scientific literature were tested for their potential to indicate human or animal faecal contamination in Switzerland. Two bacterial strains (Bacteroides thetaiotaomicron ARABA 84 and B. fragilis ARABA 19) specific for bacteriophages present in human faecal contamination and three strains (B. caccae RBA 63 and RBA 64 as well as B. fragilis KBA 60) specific for bacteriophages indicating animal faecal contamination were isolated from human wastewater and animal faecal specimens. Thereafter they were used to determine the source of surface and spring water faecal contamination. In addition, the potential of Streptococcus agalactiae was tested as a new human MST indicator. Different methods of detecting these bacteria in domestic and slaughterhouse wastewater were compared. Three DNA extraction methods and five polymerase chain reaction (PCR) assays were tested to identify the most suitable combination. The most sensitive detection method, a LightCycler real-time PCR assay, detected S. agalactiae in human wastewater but not in animal samples and showed that this bacteria is potentially useful as human MST indicator. Rhodococcus coprophilus was previously used in MST to indicate animal faecal contamination in water. For the detection of this organism, a culture-dependent method and a conventional as well as a TaqMan real-time PCR assay were previously published. The evaluation of these existing approaches, however, did not reveal any satisfactory result. A novel LightCycler real-time PCR assay was therefore designed and validated in the course of the present thesis. Compared with previously used assays, this new molecular approach showed advantages such as improved sensitivity and specificity and was much faster than the culture-based method. Sorbitol-fermenting bifidobacteria and phages infecting the Bacteroides host strains GA-17 and GB-124 were previously described to indicate human faecal contamination. Together with the newly developed and validated approaches, these established MST indicators were included in a comparative study and their potential to indicate human or animal faecal contamination in Swiss surface and spring water was tested. Based upon this assessment, sorbitol-fermenting bifidobacteria and phages of the human host strains B. thetaiotaomicron ARABA 84 and B. ovatus GB-124 can be recommended for detecting human faecal contamination in Swiss surface and drinking water. The above-mentioned approaches give evidence of the faecal input sites of contamination. To localize possible faecal input sites, they can be followed by an additional approach described in this thesis. This approach is based on the screening of multiresistant Escherichia coli and on the characterisation of selected isolates by antibiotic resistance profiles and pulsed field gel electrophoresis in order to identify identical strains. Thereby, a well equipped toolbox could be provided not only to discriminate sources of faecal contamination but also to localize possible faecal input sites

    Comment on the paper: Funding schools by formula

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    Assessing the Impact of Federal Funding to Swiss Universities: A New Performance Audit Concept

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    Opportunities and risks must undergo careful assessments in order to survive in the world of globalization. This applies not only to the private but also to the public sector, including governmental, political and educational institutions. New control mechanisms must be developed and implemented to measure and monitor the performance of political programs. These tools primarily employ evaluation techniques and performance indicators. The need for such instruments is most acute in political programs and processes where large sums of money are involved, where little information is available about the recipients of monetary contributions and where significant public emotional involvement is apparent, such as in education, social security or public health issues

    Mapping Unoccupied Electronic States of Freestanding Graphene by Angle-Resolved Low-Energy Electron Transmission

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    We report angle-resolved electron transmission measurements through freestanding graphene sheets in the energy range of 18 to 30 eV above the Fermi level. The measurements are carried out in a low-energy electron point source microscope, which allows simultaneously probing the transmission for a large angular range. The characteristics of low-energy electron transmission through graphene depend on its electronic structure above the vacuum level. The experimental technique described here allows mapping the unoccupied band structure of freestanding two-dimensional materials as a function of energy and probing angle, respectively in-plane momentum. Our experimental findings are consistent with theoretical predictions of a resonance in the band structure of graphene above the vacuum level [V. U. Nazarov, E. E. Krasovskii, and V. M. Silkin, Physical Review B 87, 041405 (2013)]

    Éditorial. Variations autour de trajectoires scolaires

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    Die vorliegende Ausgabe [...] prĂ€sentiert sieben Varia-Artikel, die sich auf unterschiedliche Weise mit dem Thema Schullaufbahnen beschĂ€ftigen. Seit den soziologischen Arbeiten von Bourdieu und Passeron ist bekannt, dass die Schule als Institution die Ungleichheiten bezĂŒglich Schulerfolg reproduziert und legitimiert. Die aktuellen Arbeiten zu diesem Thema haben eine vermehrt mikrosoziologische Ausrichtung genommen und beleuchten auch "paradoxe" Laufbahnen. [...] Ohne Absicht, ein ganzes Forschungsgebiet abzudecken, bietet diese Nummer einen Leseparcours, bei dem verschiedene Aspekte der Schullaufbahnen von der Vorschule bis zur Sekundarstufe II beleuchtet werden. Die Nummer ist entlang von drei Achsen strukturiert: (1) dem familiĂ€ren Umfeld (siehe Stamm & Edelmann), (2) der Institution Schule, einerseits aus dem Blickwinkel der Lehrerhandlungen (siehe Oswald et al.; San Martin & Veyrunes; Lombard) und andererseits bezĂŒglich Übertrittsverfahren (siehe Klapproth et al.) sowie (3) den Konzeptionen von Lehrpersonen und Studierenden der Lehrerbildung (siehe Boraita; EscaliĂ© & ChaliĂšs). (DIPF/Orig.

    EntrĂ©e dans l’écrit Ă  l’école enfantine fribourgeoise

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    Les auteures ont recueilli, en automne 2010, auprĂšs de 20 enseignant-e‐s de l’école enfantine du canton de Fribourg (Suisse), leurs pratiques dĂ©clarĂ©es sur l’EntrĂ©e dans l’Ecrit. Leurs reprĂ©sentations pĂ©dagogiques et les thĂ©ories implicites sous-­jacentes sont examinĂ©es. Le rapport s’appuie sur les entretiens semi-directifs de 45 Ă  60 minutes, rĂ©alisĂ©s auprĂšs de 20 enseignantes de l’école enfantine fribourgeoise, Ă  l’aide d’un canevas d’entretien. Une analyse qualitative de contenu et catĂ©gorielle a dĂ©gagĂ© les rĂ©sultats suivants. Au niveau des thĂ©ories implicites: la perception d’une tension apparaĂźt entre la crainte de «primariser» et la curiositĂ© et la soif d’apprendre des jeunes Ă©lĂšves. Au niveau des pratiques dĂ©clarĂ©es: les pratiques usuelles tournant autour des prĂ©noms et des mots familiers pour l’acquisition du code alphabĂ©tique sont Ă©voquĂ©es par toutes les enseignantes. Il en est de mĂȘme de la frĂ©quentation des albums dans l’intention premiĂšre de soutenir la culture de l’écrit. La production d’une dictĂ©e Ă  l’adulte faisant suite Ă  une visite, une rencontre est rĂ©guliĂšrement exploitĂ©e. Des activitĂ©s de conscience phonologique au niveau des sons et des rythmes, semblent aussi rĂ©guliĂšrement rĂ©alisĂ©es. Certaines pratiques sont rarement mentionnĂ©es au cours de nos entretiens, Ă  savoir: l’enseignement de la comprĂ©hension Ă  l’oral comme Ă  l’écrit ou encore celui de la situation d’écriture Ă©mergente provisoire. Quant au dĂ©veloppement de discussions Ă  visĂ©es philosophiques, elles n’ont pas Ă©tĂ© abordĂ©es. Au niveau des reprĂ©sentations pĂ©dagogiques: une intuition semble justifiĂ©e au regard de notre ancrage thĂ©orique, notamment l’importance de la langue orale et de son dĂ©veloppement pour l’équipement langagier du jeune enfant. Une nouvelle question Ă©merge: Est‐il possible de rĂ©duire les inĂ©galitĂ©s perçues par les enseignantes dĂšs l’école enfantine? Il conviendrait de documenter et conserver les pratiques prĂ©conisĂ©es dans la littĂ©rature et mises en Ɠuvre sur le terrain et d’encourager des groupes d’échange et d’analyse de pratiques pour soutenir l’innovation pĂ©dagogique.Die Autorinnen haben im Herbst 2010 20 KindergĂ€rtnerinnen und KindergĂ€rtnern im Kanton Freiburg (Schweiz) nach ihren Formen zur Gestaltung des Einstiegs ins Lesen befragt. Untersucht wurden ihre pĂ€dagogischen Vorstellungen und impliziten Theorien. Der Bericht stĂŒtzt sich auf teilstrukturierte Interviews von je 45 bis 60 Minuten. Eine qualitative sowie eine Inhalts- und Kategorienanalyse zeigten folgende Ergebnisse: Auf der Ebene der impliziten Theorien sind sich die LehrkrĂ€fte der Spannung bewusst, die zwischen der Neugier und dem Wissensdurst der Kinder und ihren eigenen BefĂŒrchtungen besteht, sich im Kindergarten schon mit Stoff der Primarschule zu befassen. Im Alltag verwenden alle Lehrpersonen die ĂŒblichen Praktiken rund um Vornamen und bekannte Wörter fĂŒr den Erwerb des Alphabets. BilderbĂŒcher werden vorrangig dazu eingesetzt, die Lesekultur zu fördern, Die Lehrpersonen schreiben nach einem Ausflug oder einer Begegnung auf, was die Kinder diktieren. Ebenso werden AktivitĂ€ten zur Förderung des phonologischen Bewusstseins auf der Ebene der Laute und Rhythmen offenbar regelmĂ€ssig eingesetzt. Andere Methoden wie Unterricht in mĂŒndlichem und schriftlichem Verstehen oder zufĂ€llig sich ergebende Schreibsituationen werden selten genannt, und GesprĂ€che zu philosophischen Themen werden gar nicht erwĂ€hnt. Im Hinblick auf die pĂ€dagogischen Vorstellungen der Lehrpersonen lĂ€sst sich angesichts unserer theoretischen Verankerung folgende Schlussfolgerung ziehen: FĂŒr die Entwicklung der literalen Kompetenzen der Kinder ist die Förderung der mĂŒndlichen Sprache zentral. Dabei zeigt sich eine neue Fragestellung: Wie ist es möglich, die von den Lehrerpersonen festgestellten Unterschiede zwischen den Kindern zu verringern? Die Autorinnen schlagen vor, die in der Literatur empfohlenen und in der Praxis umgesetzten Praktiken zu dokumentieren und fortzufĂŒhren sowie die Bildung von Gruppen zu fördern, die den Erfahrungsaustausch und die Analyse der eigenen Praxis unter Lehrpersonen ermöglichen, um auf diese Weise pĂ€dagogische Innovationen zu unterstĂŒtzen

    Is Formula-Based Equity Funding Enough? A Configurational Analysis of School Achievement in Victoria, Australia

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    The Australian state of Victoria uses its funding formula to correct for schools' community educational advantage, size, and location; the index of community educational advantage has been the strongest predictor of achievement historically. We use Qualitative Comparative Analysis (QCA) to examine the configurations of school and funding factors necessary and sufficient for high and low achievement, and find no consistently necessary profile but one consistently sufficient configuration for high achievement and four for low achievement. While community educational advantage is not an insurmountable dictate of school achievement, there is no consistent pathway to failure for high-advantage schools or to success for low-advantage schools. These results highlight the utility of examining school achievement through the lens of complex and configurational causality
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