- 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.
Search results
Showing 1 to 4 of 4 (0.017 seconds)| 1 |
Identification of a novel TetR-family transcription regulator, PsrA, and its involvement in Legionella pneumophila virulencePatel, Palak 18 August 2014 (has links)
Legionella pneumophila, an intracellular pathogen of protozoa, is well known for its dimorphic life cycle that alternates between the vegetative replicative form (RF) and highly infectious cyst-like form (CLF). To this date several virulence factors including LpRpoS, LpIHF, and the Dot/Icm secretion system have been found to be required for the survival of L. pneumophila in macrophage and protozoa. Here we have identified and characterised Lpg1967, an orthologue of Pseudomonas PsrA in L. pneumophila. PsrA (Lpg1967) was found to regulate the expression of previously known virulence factors such non-coding RNAs, RsmY/Z, RpoS, LpIHF, flagella and Dot/Icm Type IV secretion system. In addition, the ΔpsrA mutant strain was unable to establish Legionella-containing vacuole and thus displayed a severe growth defect in the U937 derived macrophage cell line. Thus, PsrA was found to play an important role in controlling the regulatory cascade governing virulence in L. pneumophila. / October 2014
|
| 2 |
Régulation du Système de Sécrétion de Type III de Pseudomonas aeruginosaShen, Dakang 20 December 2006 (has links) (PDF)
Pseudomonas aeruginosa est un pathogène opportuniste responsable d'infections graves chez les personnes immunodéprimées, les grands brûlés et les patients atteints de la mucoviscidose. Cette pathogénicité repose sur de nombreux facteurs de virulence dont le système de sécrétion de type III (SSTT).Nous avons observé une protéine précédemment identifiée, PsrA, nécessaire pour la pleine activation de l'expression du SSTT chez P. aeruginosa. Les analyses par retard de migration électrophorétique de fragments du promoteur de l'operon régulateur exsCEBA ont montré que la protéine recombinante PsrA pourrait se fixer sur celui-ci. Le mutant DpsrA a montré une diminution marquée de la sécrétion des effecteurs de type III et une faible résistance à la bactéricidie par des cellules de type phagocytaires, PLB-985. L'ensemble des résultats suggèrent que PsrA est un nouvel activateur qui est impliqué dans l'expression du SSTT en augmentant le niveau de la transcription d'exsCEBA.Dans un second temps, nous avons mis en évidence qu'un signal inhibiteur, de type quorum sensing inconnu et produit dans la phase stationnaire de la culture, peut réprimer l'expression du SSTT in vitro. L'analyse de milliers de mutants de transposition a montré que la production de ce signal dépend du tryptophane, qui est le précurseur de nombreux métabolites dont l'acide d'indole-3-acétic (IAA). IAA-Na et un autre membre de cette famille de molécules, le acide 1-naphthalenacétique (NAA-K) aux concentrations millimolaires peuvent en effet inhiber l'expression et la sécrétion du SSTT. L'identification précise de ce signal nécessite des investigations plus poussées.
|
| 3 |
Legal and regulatory aspects of mobile financial servicesPerlman, Leon Joseph 11 1900 (has links)
The thesis deals with the emergence of bank and non-bank entities that provide a range of unique
transaction-based payment services broadly called Mobile Financial Services (MFS) to unbanked,
underserved and underbanked persons via mobile phones.
Models of MFS from Mobile Network Operators (MNOs), banks, combinations of MNOs and banks, and
independent Mobile Financial Services Providers are covered. Provision by non-banks of ‘bank-type’
services via mobile phones has been termed ‘transformational banking’ versus the ‘additive banking’
services from banks. All involve the concept of ‘branchless banking’ whereby ‘cash-in/cash out’ services
are provided through ‘agents.’
Funds for MFS payments may available through a Stored Value Product (SVP), particularly through a
Stored Value Account SVP variant offered by MNOs where value is stored as a redeemable fiat- or mobile
‘airtime’-based Store of Value.
The competitive, legal, technical and regulatory nature of non-bank versus bank MFS models is discussed,
in particular the impact of banking, payments, money laundering, telecommunications, e-commerce and
consumer protection laws. Whether funding mechanisms for SVPs may amount to deposit-taking such that
entities could be engaged in the ‘business of banking’ is discussed. The continued use of ‘deposit’ as the
traditional trigger for the ‘business of banking’ is investigated, alongside whether transaction and paymentcentric
MFS rises to the ‘business of banking.’
An extensive evaluation of ‘money’ based on the Orthodox and Claim School economic theories is
undertaken in relation to SVPs used in MFS, their legal associations and import, and whether they may be
deemed ‘money’ in law.
Consumer protection for MFS and payments generally through current statute, contract, and payment law
and common law condictiones are found to be wanting. Possible regulatory arbitrage in relation to MFS in
South African law is discussed.
The legal and regulatory regimes in the European Union, Kenya and the United States of America are
compared with South Africa. The need for a coordinated payments-specific law that has consumer
protections, enables proportional risk-based licensing of new non-bank providers of MFS, and allows for a
regulator for retail payments is recommended. The use of trust companies and trust accounts is
recommended for protection of user funds.
| vi / Public, Constitutional and International Law / LLD
|
| 4 |
Legal and regulatory aspects of mobile financial servicesPerlman, Leon Joseph 11 1900 (has links)
The thesis deals with the emergence of bank and non-bank entities that provide a range of unique
transaction-based payment services broadly called Mobile Financial Services (MFS) to unbanked,
underserved and underbanked persons via mobile phones.
Models of MFS from Mobile Network Operators (MNOs), banks, combinations of MNOs and banks, and
independent Mobile Financial Services Providers are covered. Provision by non-banks of ‘bank-type’
services via mobile phones has been termed ‘transformational banking’ versus the ‘additive banking’
services from banks. All involve the concept of ‘branchless banking’ whereby ‘cash-in/cash out’ services
are provided through ‘agents.’
Funds for MFS payments may available through a Stored Value Product (SVP), particularly through a
Stored Value Account SVP variant offered by MNOs where value is stored as a redeemable fiat- or mobile
‘airtime’-based Store of Value.
The competitive, legal, technical and regulatory nature of non-bank versus bank MFS models is discussed,
in particular the impact of banking, payments, money laundering, telecommunications, e-commerce and
consumer protection laws. Whether funding mechanisms for SVPs may amount to deposit-taking such that
entities could be engaged in the ‘business of banking’ is discussed. The continued use of ‘deposit’ as the
traditional trigger for the ‘business of banking’ is investigated, alongside whether transaction and paymentcentric
MFS rises to the ‘business of banking.’
An extensive evaluation of ‘money’ based on the Orthodox and Claim School economic theories is
undertaken in relation to SVPs used in MFS, their legal associations and import, and whether they may be
deemed ‘money’ in law.
Consumer protection for MFS and payments generally through current statute, contract, and payment law
and common law condictiones are found to be wanting. Possible regulatory arbitrage in relation to MFS in
South African law is discussed.
The legal and regulatory regimes in the European Union, Kenya and the United States of America are
compared with South Africa. The need for a coordinated payments-specific law that has consumer
protections, enables proportional risk-based licensing of new non-bank providers of MFS, and allows for a
regulator for retail payments is recommended. The use of trust companies and trust accounts is
recommended for protection of user funds.
| vi / Public, Constitutional and International Law / LL. D.
|
Page generated in 0.4214 seconds