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Interactions moléculaires entre microorganismes au sein de biofilms en milieu marin : mise en évidence de biomolécules antibiofilm / Molecular interactions between microorganisms within marine biofilms : identification of new antibiofilm moleculesDoghri, Ibtissem 15 October 2015 (has links)
En environnement marin, la colonisation des surfaces solides par les microorganismes est progressive et suit une logique taxonomique et/ou fonctionnelle des espèces. Les biofilms ainsi formés représentent des systèmes multi-cellulaires entourés d’une matrice de substances polymériques extracellulaires (SPE). L’objectif de ce travail était de comprendre comment des acteurs microbiens (bactéries et diatomées) interagissent dans deux types de biofilms marins (biofilm benthique et biofilm sur structures métalliques portuaires). Dans cette étude, des modèles bactériens isolés de ces biofilms ont été identifiés et caractérisés. Dans un premier volet, leur capacité à former des biofilms stables a été évaluée dans différentes conditions. Quatre souches ont été ainsi sélectionnées : Flavobacterium sp. II2003, Roseobacter sp. IV3009, Roseovarius sp. VA014 et Shewanella sp. IV3014. Dans un deuxième volet, les effets des sécrétomes des bactéries marines issues du même habitat ont été évalués sur ces modèles. Deux souches se distinguent par leur capacité à produire des molécules influençant négativement la formation de biofilms : Pseudoalteromonas sp. IIIA004 produit un peptide de 2224 Da présentant une activité antibiofilm vis-à-vis de Roseovarius sp. VA014 et Pseudomonas sp. IV2006 inhibe la formation de biofilm de Flavobacterium sp. II2003. Dans les deux cas, les antibiofilms sont actifs contre un large spectre de bactéries suggérant ainsi plusieurs applications potentielles dans les domaines marin et médical. Dans le dernier volet, les effets des sécrétomes de la diatomée Navicula phyllepta ont été évalués sur les modèles de bactéries benthiques. Cette diatomée s’est distinguée par sa capacité à sécréter des polysaccharides inhibant ou stimulant la formation de biofilms selon les souches cibles. / In the marine environment, solid surface colonization by microorganisms is progressive and follows a taxonomic and/or functional logic. Biofilms formed are multi-cellular systems surrounded by a matrix of extracellular polymeric substances (EPS). The objective of this work was to understand how microbial actors (bacteria and diatoms) interact in two types of marine biofilms (benthic biofilm and biofilm on metallic structures of a harbor). In this study, bacterial models isolated from these biofilms have been identified and characterized. In a first part, their ability to form stable biofilms was evaluated under various conditions. Four strains were selected: Flavobacterium sp. II2003, Roseobacter sp. IV3009, Roseovarius sp. VA014 and Shewanella sp. IV3014. In a second part, the effects of secretomes of the marine bacteria from the same habitat were evaluated on these models. Two strains are distinguished by their ability to produce molecules negatively influencing biofilm formation: Pseudoalteromonas sp. IIIA004 produces a 2224 Da peptide with an antibiofilm activity toward Roseovarius sp. VA014 and Pseudomonas sp. IV2006 inhibits the biofilm formation of Flavobacterium sp . II2003. In both cases, the antibiofilms are active against a broad spectrum of bacteria suggesting several potential applications in marine and medical fields. In the last part, the effects of secretomes of the Navicula phyllepta diatom were evaluated on benthic bacteria models. This diatom was distinguished by its ability to secrete polysaccharides stimulating or inhibiting biofilm formation by target strains.
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La socialisation professionnelle en début de carrière : le cas d'enseignants d'EPS / The professional socialization in the begining of career : The case of physical education teachersJelen, Nathalie 17 June 2009 (has links)
La thèse est consacrée à la sociologie du début de carrière des enseignants du secondaire, à partir du cas de l’Education Physique et Sportive, entre l’obtention du concours et la troisième année de titularisation. Il s’agit de catégoriser les variables qui rendent compte des difficultés et celles qui, au contraire, facilitent les premiers moments dans le métier. Pour cela, nous avons enquêté pendant quatre années auprès d’un échantillon structuré et composé de cinquante-cinq enseignants répartis dans les académies de Lille et de Versailles. Des passations de questionnaires, des entretiens (soixante cinq), des observations du travail « en train de se faire » (dix fois une semaine) ont été réalisés. Cinq enseignants ont même été particulièrement « traités », constituant alors une sorte de « suivi longitudinal ». Finalement ce travail met en évidence les tensions entre l’apprentissage du métier dans les instances de formation et celui sur le terrain, entre les nécessités de respecter une culture professionnelle et de s’accommoder aux situations d’enseignement. Mais celles-ci procèdent de diverses variables qui s’expriment de façons équivoques. Nous proposons de systématiser cette complexité en montrant comment l’enseignant parvient à s’adapter. La « mastérisation » de la formation enseignante améliorera-t-elle cela ? Et, ce faisant, la transmission des savoirs en EPS tout comme les transformations qu’elle implique au niveau des élèves ? On peut se demander pourquoi la thèse ne répond pas définitivement à ces questions. Au lecteur d’apprécier si c’est à cause de l’hétérogénéité des configurations de débuts de carrières, grâce à la diversité des profils de débutants ou de la discipline d’enseignement choisie. / The thesis deals with the sociology of the beginning of career of the teachers in secondary school, from the case of the Physical and Sports Education, between the passing of the examination and the third year of actual professional appointment. The point here is to categorize the variables which report difficulties and those which on the contrary facilitate the first moments in the job. For that purpose, we investigated for four years with a structured sample consisting of fifty-five teachers appointed all over the academies (i.e. regional educational authorities) of Lille and Versailles. Signings of questionnaires, interviews (sixty- five), observations of the work “in progress” (ten times a week) were carried out. Five teachers were particularly « studied », even, establishing then a kind of “longitudinal follow-up”. Finally this work brings to light the tensions between the learning of the job by the official training authorities and that on the ground, between the necessities of respecting a professionnal culture and adapting to the actual teaching situations. But these proceed of diverse variables which express themselves in ambiguous manners. We suggest systematizing this complexity by showing how the teacher submits to the job in order to succeed in adapting. Will the current “masterization” of the teaching training programmes improve it ? And thus, the transmission of the knowledge and skills in Physical Education as well as the alterations which it implies at the level of the pupils ? We may wonder why the thesis does not give a definite answer to these questions. Now it is up to the reader to appreciate if it is either because of the heterogeneousness of the configurations of career debuts, thanks to the variety of the beginners’ profiles or the chosen teaching subject.
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Bacillus subtilis biofilm formation under extreme terrestrial and simulated extraterrestrial conditionsFuchs, Felix Matthias 13 May 2020 (has links)
No description available.
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Fasomvandlingsmaterial : Brandrisker med energilagring i byggnaderWolf, Jonathan January 2021 (has links)
Energy storage with the help of different materials is something that has been around for a long time. Structures such as concrete or brick use their high thermal mass to store energy in the form of temperature increase, sensible heat, of the respective material. Energy storage in the form of sensible heat is relatively small in capacity, which means that large masses of building material are required to give a significant effect. Concrete, for example, requires 4 kJ/kg to increase in temperature by 1 °C. Now society has begun to look more closely at other materials that can be used for energy storage and temperature stabilization in buildings. Phase change materials are unique materials that use the change in phases between different aggregation states to store energy in the form of latent heat. It is mainly phase change between solid and liquid that is used since gaseous form would involve large volume changes. An everyday example of a material that undergoes a phase change is water. Water requires 334 kJ/kg to go from 0 ˚C ice (solid) to 0 ˚C water (liquid). Water is a very powerful phase change material but cannot be used in buildings as it melts at 0 ˚C. Therefore, other materials have been developed to meet the requirement that the melting take place at the desired temperature, usually room temperature. The different phase change materials can be divided into three different groups: organic, inorganic and eutetic materials. All groups come with their own advantages and disadvantages. Organic materials are stable materials in the sense that they can phase change in repeated cycles which makes them the popular choice when it comes to buildings. One disadvantage that most organic materials possess is that they are flammable. The choice of phase change material will affect the quality of the building and it is therefore important that the knowledge about these materials is adopted before they become more widespread.
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Analýza řídicích procedur v mobilních sítích čtvrté generace / Analysis of control procedures in 4th generation mobile networksSchaller, Lukáš January 2018 (has links)
The subject of the diploma thesis are procedures in EPS network related to the operation of mobile terminals. In the introduction of my work I described the EPS system, including the quality of services and bearers. The following section focuses on control procedures in the EPS system such as attach network procedure, detach procedure, service request, handover or tracking area procedure. Further, three technologies for Internet of Things were described, namely EC-GSM-IoT, LTE-M and NB-IoT. All the procedures mentioned above were also captured in the experimental VUT EPS network and analyzed by TravelHawk using software M5 and Wireshark. Theoretical and practical findings were subsequently used out for setting of laboratory task for subject MKPM.
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Analýza řídicích procedur v sítích EPS-IMS / Control Procedure Analysis in EPS-IMS NetworksŠubrt, Jan January 2017 (has links)
The master thesis is focused on control procedures in EPS-IMS networks. Firstly the thesis describes systems IMS and EPS. The second part of thesis includes the theory of control procedures in EPS such as cell acquisition, random access procedure, identification of subscriber, authentication of subscriber, security procedures, tracking area procedure, default bearer creation, implementation of CSFB procedure and detach procedure. Processes related to subsystem IMS such as registration to IMS, bearer creation for IMS signalling and voice service VoLTE are the next part of thesis. The next main topic is the VoLTE implementation problematic and VoLTE cooperation with diverse terminals. There is also explained the principle of Circuit Switched Fallback for realization voice services in EPS without VoLTE service. All procedures mentioned above except of procedures which are related to IMS were captured and analyzed using software Wireshark and QualiPoc. The final part of the thesis is lab task creation based of the analyzed messages.
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Consumers' views towards electronic payment tools : users' comparison between Alipay in China and Swish in SwedenQiu, Zizhou, Shi, Yuan, Zheng, Ye January 2019 (has links)
In order to achieve a cashless society, many countries have started to use electronic payment methods and tools to replace traditional payment methods. China and Sweden already have mature electronic payment tools, Swish, and Alipay. In this research, a phenomenological approach was used to interview users comparing two electronic payment tools, the Chinese Alipay and the Swedish Swish. The analysis of the respondents’ answers shows that convenience, security, and cost of electronic payment tools are the most important aspects to them, which is in line with previous research on acceptance, adoption and use of new technology, not only electronic payment tools. Convenience and security were more important. However, too much convenience will affect the interviewees' trust in electronic payment tools because it will make interviewees feel unsafe. Respondents' trust is affected by their own acquaintance; they trust electronic payment tools they know better.
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Plast- och frigolithantering på BMC : Källsortering 2.0Johansson, Ida, Tjell, Torun, Bäck, Axel, Olesen, Stella, Sandor, Rebecca, Wålinder, Jonatan January 2023 (has links)
År 2022 genomfördes en plockanalys på Biomedicinskt centrum, BMC, i Uppsala för att bland annat studera mängd och sorts plast som behandlas vid källsortering. Fastighetsägaren Akademiska Hus har som övergripande mål att nå klimatneutralitet år 2035 och arbetar mot detta med andra lokala aktörer i fokusgruppen Jakten på plasten. Fokusgruppen är ett forum där olika aktörer kan mötas för att öka uppmärksamhet kring källsortering och återvinning. Plockanalysen visade att det finns möjlighet till förbättring kring återvinningen av plast. Denna rapport ämnar studera hur källsorteringssystemet ser ut idag och vilka orsaker som ligger till grund för att plast sorteras ut felaktigt. I slutsatserna från plockanalysen lyftes frigolit fram som särskilt problematisk. Den skickas enligt instruktion som restavfall, vilket beror på frigolitens skrymmande egenskaper och bristande möjligheter till liknande komprimering som övrigt plastavfall. I containern för restavfall finns en komprimator som lämpar sig bättre för frigolit. I rapporten har extra fokus lagts på just frigoliten och alternativa lösningar till återvinning har studerats utifrån deras klimatnytta. I en enkätundersökning framkom det att medarbetare på BMC i hög utsträckning tycker att källsortering av plast är viktigt men att det inte alltid är tydligt hur plasten ska sorteras ut. Både när det kommer till riktlinjer från BMC men också utifrån osäkerhet kring vilken typ av plast det är och därav hur den ska sorteras. Förslag på lösningar till detta är att öka informationen genom att se till att all information finns tillgänglig på både svenska och engelska och grundligare information skulle kunna finnas att tillgå via exempelvis en QR-kod på sopkärlen. Om man vill förnya det visuella systemet kring återvinning skulle loggorna kunna uppdateras utifrån ett standardiserat nordiskt system som Avfall Sverige varit med att ta fram. Om frigolit skickas till materialåtervinning istället för energiåtervinning skulle klimatnyttan bli cirka 400 kg koldioxidekvivalenter per år. Transporten har en relativt liten inverkan på klimatnyttan medan återvinningen av frigoliten spelar större roll. Därför kan det finnas intresse av att skicka frigolit till materialåtervinning, även om detta inte kan göras lokalt likt energiåtervinning. Kostnader för de olika alternativen har ej jämförts men en komprimeringsmaskin skulle kunna minska frigolitens volym med upp till en faktor 50. En sådan maskin skulle troligtvis kosta mer jämfört med att, som nu, sortera ut frigoliten i restavfall. Med alternativet att komprimera frigolit skulle transportutgifter kunna minskas. Som framtida steg skulle djupare samarbeten mellan producenter, användare och återvinnare kunna utvecklas för att hitta lösningar som fungerar för samtliga aktörer i kedjan. Jakten på plasten lämpar sig för detta där Akademiska Hus kan knyta band till andra företag med liknande behov för att tillsammans hitta kostnadseffektiva lösningar på exempelvis uppsamling och transport av frigolit för att öka attraktiviteten kring materialåtervinning jämfört med energiåtervinning.
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Effects of Extracellular Polymeric Substance Composition on Bacteria Disinfection by MonochloramineCoburn, Kimberly Mary January 2012 (has links)
No description available.
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A Mathematical Model of Biofilm Growth and DecayNassar, David Aziz 09 June 2009 (has links)
No description available.
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