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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Formování postojů žáků v hodinách zeměpisu na příkladu problematiky kůrovcových kalamit / Shaping of Students' Attitudes in Geographical Education - The Issue of Ips Typographus Outbreaks

Faflák, Jiří January 2013 (has links)
Shaping of students' attitudes in geographical education - the issue of Ips typographus outbreaks Abstract The diploma thesis deals with shaping the students' attitudes by utilising various texts during the geography classes. This experiment is shown on particular problem of Spruce Bark Beetle in the National Park of Šumava. There are two main streams towards this issue of Spruce Bark Beetle-one of them promotes the idea of incorporating the human intervention, while reducing the disaster, the other follows the opposite attitude towards the outbreak of the Spruce Bark Beetle, and that is not to intervene at all and to leave the destructed vegetation to regenerate. The backbone of the thesis is represented by a survey that aims at finding attitudes towards the problem mentioned above. Moreover, the survey also questions the way the attitudes change depending on critical reading of distinctive texts. Two main questions are posed in this research. The results are graphically depicted and commented upon in the thesis. The research shows the extent to which it is possible to influence the students' opinion utilising quality study texts. Key words: Spruce Bark Beetle (Ips typographus), National park Šumava, Spruce Bark Beetle outbreak, geographical education, critical thinking, active reading, shaping of attitudes
152

Modélisation des néoplasmes myéloprolifératifs sporadiques et familiaux avec les cellules de patients induites à la pluripotence / Modeling of sporadic and familial myeloproliferative neoplasms with induced pluripotent stem cells derived from Patients

Saliba, Joseph 21 October 2013 (has links)
Les néoplasmes myéloprolifératifs (NMP) sont des maladies acquises touchant la cellule souche hématopoïétique et qui aboutissent à une hyperproduction de cellules sanguines dont le phénotype dépend du type du NMP. La mutation la plus proéminente des NMP est JAK2V617F. Elle peut être associée à différents NMP sporadiques et familiaux.Une des problématiques, non résolue, des NMP est de comprendre comment une même mutation JAK2V617F peut donner plusieurs maladies. Notre hypothèse est que le phénotype observé pourrait dépendre du nombre de copies de JAK2V617F. Une autre inconnue concerne la cause génétique des formes familiales.Pour ces raisons, nous avons modélisé des NMP sporadiques et un cas familial par les iPS. Cette approche devrait nous permettre d’une part, de comparer les effets de JAK2V617F à l’état hétérozygote et homozygote sur l’hématopoïèse et d’autre part, d’avancer dans la compréhension des effets d’une duplication de 5 gènes que nous avons identifiée, par une approche de génétique, comme un facteur de susceptibilité chez 2 familles.Dans la première partie du travail, concernant la modélisation des NMP sporadiques, nous avons montré que JAK2V617F augmente la prolifération des cellules myéloïdes obtenues à partir des iPS. D’autre part, nous avons pu mettre en évidence une différence marquée dans l’hypersensibilité à la TPO et à l’EPO entre les lignées hétérozygotes et homozygotes pour JAK2V617F permettant d’expliquer le phénotype des PV et des TE. Dans la deuxième partie concernant les NMP familiaux, nous avons pu mettre en évidence un phénotype spécifique attribuable à la seule duplication. Grace à ce modèle, nous allons pouvoir identifier le(s) gène(s) responsable(s) du phénotype. Ce travail apporte la preuve de concept que les iPS sont un bon outil pour modéliser les NMP sporadiques et familiaux et qu’elles peuvent servir comme outils de criblage de petites molécules développées à des fins thérapeutiques. / Myeloproliferative neoplasms (MPN) are clonal hematologic diseases which lead to an overproduction of blood cells. The affected myeloid lineage depends on the type of MPN. JAK2V617F is the most predominant mutation in MPN and can be associated with various sporadic and familial cases.One main issue to address in MPN is to understand how a single mutation JAK2V617F can give rise to several diseases. Our hypothesis is that this phenotypic heterogeneity might be due to the JAK2V617F gene dosage. Another goal is to identify the genetic cause of familial MPN.For these reasons, we modeled sporadic and familial MPN cases with iPS technology. This approach allowed us i) to compare the impact of heterozygous and homozygous JAK2V617F mutation on hematopoiesis and ii) to get insight into the effects of a 5 genes duplication that we identified as a susceptibility locus uncovered by a genetic approach in 2 families.In the first part of the work concerning sporadic MPN modeling, we showed that JAK2V617F increases iPS myeloid potential. Furthermore, we showed a marked difference in the TPO and EPO hypersensitivity between heterozygous and homozygous JAK2V617F iPS cell lines that could be linked to the difference between PV and ET. In the second part of the work, we demonstrated a specific phenotype due to the sole duplication. This model will allow us to identify the gene(s) responsible of the phenotype. This study brings the proof of concept that iPS can be used for sporadic and familial MPN modeling and drug screening.
153

Fach- und Informationsportale der UB Freiburg – neue Entwicklungen

Sühl-Strohmenger, Wilfried 29 August 2007 (has links) (PDF)
Wilfried Sühl-Strohmenger, UB Freiburg, stellte am Beispiel einiger Fächer die von der Universi­tätsbibliothek Freiburg unter fachlichen Gesichtspunkten strukturierten Informations­portale - die „Freiburger Fachportale“ - vor. Sie sind als Wissenschaftsportale zu qualifizieren und erschließen digitale wie analoge, netzbasierte wie unverbunden dislozierte Ressourcen, im Hinblick auf die bessere Transparenz bei Bibliotheks- und Internetressourcen. Den Nutzern wird durch die Fach- und Informationsportale einer­seits der Überblick über die Fachressourcen erleichtert, andererseits der direkte und rasche Rechercheeinstieg in relevante Services ermöglicht.
154

Intrångsdetektering i processnätverk / Intrusion detection in process networks

Fahlström, Albin, Henriksson, Victor January 2018 (has links)
The threat against industrial networks have increased, which raises the demands on the industries cybersecurity. The industrial networks are not constructed with cybersecurity in mind, which makes these systems vulnerable to attacks. Even if the networks outer protection is deemed sufficient, the system may still be infected. This risk demands an intrusion detection system (IDS) that can identify infected components. An IDS scans all traffic of a point in the network and looks for traffic matching its detections parameters, if a match is made the IDS will send an alarm to the administrators. It can also analyze the network traffic using a behavior based method which means that the IDS will alert administrators if network activity deviates from the normal traffic flow. It is of vital essence that the IDS do not impair with the system, an outage of the industrial process can have a high cost for the industry. This report aims to put forward plans for the implementation of an IDS in one of Mälarenergi AB’s industrial networks, this will be made using the Bro and Snort intrusion detection systems. / Hoten mot industrinätverken har blivit större vilket har ställt högre krav på industriernas cybersäkerhet. Industrinätverk är ofta inte konstruerade med cybersäkerhet i åtanke, vilket har gjort dessa system sårbara mot attacker. Även om nätverkets yttre skydd anses gott går det inte att vara säker på att ett industrinätverk förblir osmittat. Detta ställer krav på någon form av intrångsdetekteringssystem (IDS) som kan upptäcka infekterad utrustning och suspekt datatrafik i nätverket. En IDS skannar alla paket vid en viss punkt i nätverket, om IDS:en upptäcker något paket som matchar med dess signatur kommer den att larma en administratör. IDS:en kan även använda beteendeanalys där den larmar om nätverksaktiviteten avviker från det normala. Det är mycket viktigt att en IDS inte orsakar avbrott i industriprocessen, om en process stannar kan det innebära stora kostnader för industrin. Denna rapport syftar till att lämna ett lösningsförslag på en IDS-implementation till ett av Mälarenergi AB: s processnätverk, lösningen konstruerades med hjälp av IDS:erna Bro och Snort. / <p>Vissa bilder i den elektroniska rapporten har tagits bort av upphovrättsliga skäl. Författarna har bedömt att rapporten är förståelig även utan dessa bilder. </p>
155

Modélisation de maladies neurodégénératives à l’aide de cellules souches pluripotentes induites humaines / Modeling of neurodegenerative diseases using human induced pluripotent stem cells

Lemonnier, Thomas 25 September 2012 (has links)
La technologie de reprogrammation de cellules somatiques en cellules souches pluripotentes induites (iPS) offre aujourd’hui l’opportunité de modéliser des maladies neurodégénératives et d’étudier des neurones de patients. Nous avons utilisé cette technologie pour générer deux modèles de maladies neurodégénératives : la mucopolysaccharidose de type IIIB (MPSIIIB) et la forme ALS2 de la sclérose latérale amyotrophique (SLA). Dans le modèle MPSIIIB, nous avons montré que les iPS et les neurones de patients présentaient des défauts caractéristiques de la pathologie telle que l’accumulation de vésicules de surcharge. Des altérations de l’appareil de Golgi dans ces cellules ont également été mises en évidence. Une analyse du transcriptome de précurseurs neuraux MPSIIIB a montré des modifications transcriptionnelles touchant notamment des gènes impliqués dans les interactions de la cellule avec la matrice extracellulaire. Ainsi, dans une seconde étude, des altérations de la migration et de l’orientation de cellules de souris mutantes MPSIIIB ou de patients ont été démontrées. Ces altérations pourraient être responsables des perturbations de la neurogénèse et de la neuritogénèse chez les enfants malades. Dans le modèle SLA/ALS2, nous avons montré que les neurones de patients présentaient des défauts incluant une diminution de la surface des endosomes et des anomalies de la croissance neuritique. Alors qu’il n’existait jusqu’alors aucun modèle cellulaire pertinent reproduisant cette maladie, ce modèle permettra à présent d’étudier les processus physiopathologiques impliqués dans la maladie. En conclusion, la génération de cellules iPS permet de modéliser des maladies neurodégénératives et d’étudier les processus physiopathologiques qui sont associés sur des neurones humains en culture. Ces modèles cellulaires pourraient permettre dans un avenir proche de réaliser des criblages de molécules à visée thérapeutique / Reprogramming technology of somatic cells in induced pluripotent stem cells (iPS) now offers the opportunity to model neurodegenerative diseases and to study patient’s neurons. We used this technology for generating two models of neurodegenerative diseases: the muccopolysaccharidosis type IIIB (MPSIIIB) and the ALS2 form of amyotrophic lateral sclerosis (ALS). In the MPSIIIB model, we have shown that iPS and neurons of patients had characteristic defects of the disease such as the accumulation of storage vesicles. Alterations of the Golgi apparatus in these cells were also highlighted. Transcriptome analysis of MPSIIIB neural precursors showed transcriptional changes involving particularly genes implicated in cell-extracellular matrix interactions. Thus, in a subsequent study, alterations of migration and orientation of MPSIIIB mutant mouse cells and MPSIIIB patients’ cells have been demonstrated. These alterations may be responsible for the disruption of neurogenesis and neuritogenesis in sick children. In the ALS2 model, we have shown that patients’ neurons had defects including decreased endosomes’ surface and abnormal neurite outgrowth. As there was previously no relevant cellular model reproducing the disease, this model will now allow the study of physiopathological processes involved in the disease. In conclusion, the generation of iPS cells allows to model neurodegenerative diseases and to study associated physiopathological processes on cultured human neurons. These cell models could allow in the near future the screening of molecules of potential therapeutical interest
156

Bearbetningstid och CPU-användning i Snort IPS : En jämförelse mellan ARM Cortex-A53 och Cortex-A7 / Processing time and CPU usage in Snort IPS : A comparision between ARM Cortex-A53 and Cortex-A7

Nadji, Al-Husein, Sarbast Hgi, Haval January 2020 (has links)
Syftet med denna studie är att undersöka hur bearbetningstiden hos Snort intrångsskyddssystem varierar mellan två olika processorer; ARM Cortex-A53 och Cortex-A7. CPU-användningen undersöktes även för att kontrollera om bearbetningstid är beroende av hur mycket CPU Snort använder. Denna studie ska ge kunskap om hur viktig en processor är för att Snort ska kunna prestera bra när det gäller bearbetningstid och CPU användning samt visa det uppenbara valet mellan Cortex-A53 och Cortex-A7 när man ska implementera Snort IPS. Med hjälp av litteratursökning konstruerades en experimentmiljö för att kunna ge svar på studiens frågeställningar. Snort kan klassificeras som CPU-bunden vilket innebär att systemet är beroende av en snabb processor. I detta sammanhang innebär en snabb processor gör att Snort hinner bearbeta den mängd nätverkstrafik den får, annars kan trafiken passera utan att den inspekteras vilket kan skada enheten som är skyddat av Snort. Studiens resultat visar att bearbetningstiden i Snort på Cortex-A53 och Cortex-A7 skiljer sig åt och en tydlig skillnad i CPU-användning mellan processorerna observerades. Studien visar även kopplingen mellan bearbetningstiden och CPUanvändning hos Snort. Studiens slutsats är att ARM Cortex-A53 har bättre prestanda vid användning av Snort IPS avseende bearbetningstid och CPU-användning, där Cortex-A53 har 10 sekunder kortare bearbetningstid och använder 2,87 gånger mindre CPU. / The purpose of this study is to examine how the processing time of the Snort intrusion prevention system varies on two different processors; ARM Cortex-A53 and CortexA7. CPU usage was also examined to check if processing time depends on how much CPU Snort uses. This study will provide knowledge about how important a processor is for Snort to be able to perform well in terms of processing time and CPU usage. This knowledge will help choosing between Cortex-A53 and Cortex-A7 when implementing Snort IPS. To achieve the purpose of the study a literature search has been done to design an experimental environment. Snort can be classified as CPU-bound, which means that the system is dependent on a fast processor. In this context, a fast processor means that Snort is given enough time to process the amount of traffic it receives, otherwise the traffic can pass through without it being inspected, which can be harmful to the device that is protected by Snort. The results of the study show that the processing time in Snort on Cortex-A53 and Cortex-A7 differs and an obvious difference in CPU usage between the processors is shown. The study also presents the connection between processing time and CPU usage for Snort. In conclusion, ARM Cortex-A53 has better performance when using Snort IPS in terms of processing time and CPU usage, Cortex-A53 has 10 seconds less processing time and uses 2,87 times less CPU.
157

Detekce slow-rate DDoS útoků / Detection of slow-rate DDoS attacks

Sikora, Marek January 2017 (has links)
This diploma thesis is focused on the detection and protection against Slow DoS and DDoS attacks using computer network traffic analysis. The reader is introduced to the basic issues of this specific category of sophisticated attacks, and the characteristics of several specific attacks are clarified. There is also a set of methods for detecting and protecting against these attacks. The proposed methods are used to implement custom intrusion prevention system that is deployed on the border filtering server of computer network in order to protect Web servers against attacks from the Internet. Then created system is tested in the laboratory network. Presented results of the testing show that the system is able to detect attacks Slow GET, Slow POST, Slow Read and Apache Range Header and then protect Web servers from affecting provided services.
158

Fach- und Informationsportale der UB Freiburg – neue Entwicklungen

Sühl-Strohmenger, Wilfried 29 August 2007 (has links)
Wilfried Sühl-Strohmenger, UB Freiburg, stellte am Beispiel einiger Fächer die von der Universi­tätsbibliothek Freiburg unter fachlichen Gesichtspunkten strukturierten Informations­portale - die „Freiburger Fachportale“ - vor. Sie sind als Wissenschaftsportale zu qualifizieren und erschließen digitale wie analoge, netzbasierte wie unverbunden dislozierte Ressourcen, im Hinblick auf die bessere Transparenz bei Bibliotheks- und Internetressourcen. Den Nutzern wird durch die Fach- und Informationsportale einer­seits der Überblick über die Fachressourcen erleichtert, andererseits der direkte und rasche Rechercheeinstieg in relevante Services ermöglicht.
159

Inomhuspositioneringssystem : Personlig navigation inomhus via mobiltelefon / Indoor Positioning System : Personal indoor navigation via mobile phone

Johansson, Charlie, Frid, Martin January 2015 (has links)
GPS används idag för personlig navigering men dessvärre är GPS beroende av fri sikt och presterar sämre i en inomhusmiljö. Ett IPS, inomhuspositioneringssystem, skulle komplet-tera GPS:ens funktion samt öppna dörrar för nya användningsområden inom positionering. I detta examensarbete studerades metoder och tekniker för att möjliggöra ett IPS för en mo-bil enhet. Där teknikerna och metoderna verifieras för att kunna implementeras i en mobil-telefon.En prototyp för ett IPS framställdes för att utreda möjligheterna att navigera i en inomhus-miljö. En radiofingeravtrycksmetod baserat på RSSI-mätningar från Bluetooth-enheter im-plementerades och integrerades med en dödräkningsmetod som använder en IMU för att positionera användaren. Utefter tester och simuleringar utförts presenteras resultatet i form av figurer och tabeller. Med hjälp av prototypen går det att navigera med ett medelfel på 0,26m. Resultatet visar också på att en integrering av två metoder är att föredra då de kan komplettera varandras svagheter. / The GPS is used today for personal navigation, however GPS performs less well in an in-door environment due to the dependency of line of sight. The IPS, Indoor Positioning Sys-tem, will complement the function of the GPS and open doors for new applications. In this thesis studies of methods and techniques are made to enable IPS for a portable device. These techniques and methods are verified that they could be implemented in a smartphone.A prototype was designed to examine the possibility to navigate in an indoor environment. The prototype was built on a RSSI-based radio fingerprinting method over Bluetooth. This method was integrated with a dead reckoning system using an IMU to follow the motions of the user. Tests and simulations are performed along with the results presented in tables and figures. The result shows that it is possible to navigate using the prototype with a mean error of 0.26m. Results are also showing that two methods are to prefer, as they will com-plement each other’s weaknesses.
160

Studying Tumor-Derived and Induced Pluripotent Stem Cell- Derived Organoids for Kidney Cancer Research

Bauer, Daniel 02 February 2022 (has links)
Trotz der breiten Anwendung zielgerichteter Therapien und Immuncheckpoint-Inhibitoren, liegt die 5-Jahres-Überlebensrate beim metastasierten klarzelligen Nierenkarzinom (ccRCC) unter 15%. Um den Therapieerfolg für Patienten zu verbessern, werden neue Modelle benötigt, die die Tumorheterogenität rekapitulieren und eine personalisierte Therapieentwicklung ermöglichen. Im ersten Teil dieser Doktorarbeit habe ich Organoidkulturen direkt aus Patiententumoren und sortierten Krebsstammzellen (CSCs) etabliert und diese Organoide im Detail charakterisiert. Die Rolle von WNT und NOTCH, die zuvor in ccRCC CSCs bestimmt wurde, wurde in Organoiden bestätigt und konnte mit Hilfe von molekularen Inhibitoren als therapeutische Schwachstelle ausgenutzt werden. Diese Ergebnisse heben das Potenzial von Patienten-abgeleiteten Organoiden (PDOs) für die personalisierte Medizin und das Potenzial von WNT und NOTCH Inhibierung in der ccRCC Behandlung hervor. PDOs stellen Werkzeuge für die personalisierte Medizin dar, geben jedoch wenig Einblick in die frühen Stufen der Tumorentstehung. Deshalb habe ich im zweiten Teil meiner Dissertation VHL, PBRM1 und SETD2 – die drei am häufigsten mutierten Gene in ccRCC – mit einer induzierbaren CRISPR-Cas9 Strategie in induzierten pluripotenten Stammzellen (iPSC)-abgeleiteten Nierenorganoiden targetiert. Ich differenzierte iPSCs in nierenspezifische Zelltypen aus sowohl metanephrischem Mesenchym als auch Ureterknospen-Epithelium. Knockout von VHL, PBRM1 und SETD2 führte zur Hochregulation von Hypoxie-induzierbaren Genen in Organoiden und Knockout Effekte konnten durch längere Kultivierungszeiten und Zellselektion via FACS verstärkt werden. Obwohl ccRCC-spezifische Signalwege aktiviert wurden, wurde kein Wachstumsvorteil der transformierten Zellen beobachtet. Dennoch stellen diese Organoide ein einzigartiges Modell dar, das auf andere Nephropathien angewendet werden könnte, um die Nieren- und Nierenkrebsforschung weiter voranzutreiben. / Despite the widespread application of targeted therapies and immune checkpoint inhibitors, the five-year survival rate for metastatic clear cell renal cell carcinoma (ccRCC) is below 15%, as unpredictable progression, therapy resistance, and tumor relapse occur. In order to improve patient outcome, novel models are needed that recapitulate tumor heterogeneity and allow for a more personalized therapy development. In the first part of my PhD thesis, I established organoid cultures directly from patient tumors and sorted cancer stem cells (CSCs) and I characterized these organoids thoroughly. The roles of WNT and NOTCH, which were previously determined in ccRCC CSCs, were confirmed in organoid cultures and could be exploited as a therapeutic weakness via small molecule inhibition. These results highlight the potential of patient-derived organoids (PDOs) for personalized therapy and further the potential of WNT and NOTCH inhibition for ccRCC treatment. PDOs present suitable tools for personalized medicine, but provide little insight into early stages of tumorigenesis. Therefore, in the second part of my thesis, I targeted VHL, PBRM1, and SETD2 – the three most frequently mutated genes in ccRCC – using an inducible CRISPR-Cas9 genome editing strategy in induced pluripotent stem cell (iPSC)-derived kidney organoids. I used a previously published protocol to differentiate iPSCs into kidney-specific cells originating from both metanephric mesenchyme and ureteric bud epithelium. Knockout of VHL, PBRM1, and SETD2 led to the upregulation of hypoxia-inducible genes in organoids and knockout effects could be enhanced by longer cultivation times and cell selection through FACS. Although ccRCC-specific signaling pathways were activated, a growth advantage of transformed cells was not observed. Nevertheless, these organoids present a unique model that could be applied to other nephropathies to further advance kidney and kidney cancer research.

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