432 research outputs found
Personal rights management (PRM) : enabling privacy rights in digital online media content
With ubiquitous use of digital camera devices, especially in mobile phones, privacy is no longer threatened by governments and companies only. The new technology creates a new threat by ordinary people, who now have the means to take and distribute pictures of oneâs face at no risk and little cost in any situation in public and private spaces. Fast distribution via web based photo albums, online communities and web pages expose an individualâs private life to the public in unpreceeded ways. Social and legal measures are increasingly taken to deal with this problem. In practice however, they lack efficiency, as they are hard to enforce in practice. In this paper, we discuss a supportive infrastructure aiming for the distribution channel; as soon as the picture is publicly available, the exposed individual has a chance to find it and take proper action.Wir stellen ein System zur Wahrnehmung des Rechts am eigenen Bild bei der Veröffentlichung digitaler Fotos, zum Beispiel von Handykameras, im Internet vor. Zur Entdeckung der Veröffentlichung schlagen wir ein Watermarking-Verfahren vor, welches das Auffinden der Bilder durch die potentiell abgebildeten Personen ermöglicht, ohne die Rechte des Fotografen einzuschrĂ€nken
Wendy, the Good Little Fairness Widget
The advent of decentralized trading markets introduces a number of new
challenges for consensus protocols. In addition to the `usual' attacks -- a
subset of the validators trying to prevent disagreement -- there is now the
possibility of financial fraud, which can abuse properties not normally
considered critical in consensus protocols. We investigate the issues of
attackers manipulating or exploiting the order in which transactions are
scheduled in the blockchain. More concretely, we look into relative order
fairness, i.e., ways we can assure that the relative order of transactions is
fair. We show that one of the more intuitive definitions of fairness is
impossible to achieve. We then present Wendy, a group of low overhead protocols
that can implement different concepts of fairness. Wendy acts as an additional
widget for an existing blockchain, and is largely agnostic to the underlying
blockchain and its security assumptions. Furthermore, it is possible to apply a
the protocol only for a subset of the transactions, and thus run several
independent fair markets on the same chain
Impact of implementation choices on quantitative predictions of cell-based computational models
âCell-basedâ models provide a powerful computational tool for studying the mechanisms
underlying the growth and dynamics of biological tissues in health and disease. An
increasing amount of quantitative data with cellular resolution has paved the way for
the quantitative parameterisation and validation of such models. However, the numerical
implementation of cell-based models remains challenging, and little work has been done to
understand to what extent implementation choices may influence model predictions. Here,
we consider the numerical implementation of a popular class of cell-based models called
vertex models, which are often used to study epithelial tissues. In two-dimensional vertex
models, a tissue is approximated as a tessellation of polygons and the vertices of these
polygons move due to mechanical forces originating from the cells. Such models have been
used extensively to study the mechanical regulation of tissue topology in the literature.
Here, we analyse how the model predictions may be affected by numerical parameters,
such as the size of the time step, and non-physical model parameters, such as length
thresholds for cell rearrangement. We find that vertex positions and summary statistics
are sensitive to several of these implementation parameters. For example, the predicted
tissue size decreases with decreasing cell cycle durations, and cell rearrangement may
be suppressed by large time steps. These findings are counter-intuitive and illustrate that
model predictions need to be thoroughly analysed and implementation details carefully
considered when applying cell-based computational models in a quantitative setting
Rights management technologies: A good choice for securing electronic healthrecords?
Advances in healthcare IT bring new concerns with respect to privacy and security. Security critical patient data no longer resides on mainframes physically isolated within an organization, where physical security measures can be taken to defend the data and the system. Modern solutions are heading towards open, interconnected environments where storage outsourcing and operations on untrusted servers happen frequently. In order to allow secure sharing of health records between different healthcare providers, Rights Management Techniques facilitating a datacentric protection model can be employed: data is cryptographically protected and allowed to be outsourced or even freely float on the network. Rather than relying on different networks to provide confidentiality, integrity and authenticity, data is protected at the end points of the communication. In this paper we compare Enterprise/Digital Rights Management with traditional security techniques and discuss how Rights Management can be applied to secure Electronic Health Records
Diversity-oriented staff management in libraries: national and international examples
Das Thema âDiversity Managementâ nimmt immer mehr an Bedeutung zu. Dies liegt vor allem daran, dass die Gesellschaft immer vielfĂ€ltiger wird. Auch Bibliotheken können einen Nutzen aus Diversity Management ziehen und sich darum bemĂŒhen, dass ihr Personal die VielfĂ€ltigkeit der Gesellschaft, der sie dienen, widerspiegelt. Die vorliegende Arbeit untersucht, inwieweit Diversity Management in Bibliotheken vorhanden ist und zeigt Beispiele aus dem In- und Ausland, die einen Eindruck davon vermitteln, wie man ein Diversity-orientiertes Personalmanagement in Bibliotheken integrieren kann.âDiversity Managementâ is becoming an important issue as the community is getting diverse more and more. Libraries can benefit from Diversity Manage-ment, too, and they can try to reflect the diverse community, which they are serving. The presented thesis reviews how Diversity Management is being used in libraries and shows national and international examples that give an impression about how to integrate a Diversity-oriented staff management in libraries
Charakterisierung des Spike Proteins des Schweren Akutenatemnotsyndrom Coronavirus
Charakterisierung des Spike Proteins des Schweren Akutenatemnotsyndrom Coronavirus
Effect of daptomycin and vancomycin on Staphylococcus epidermidis biofilms: An in vitro assessment using fluorescence in situ hybridization
Colonization of in-dwelling catheters by microbial biofilms is a major concern in patient health eventually leading to catheter-related blood stream infections. Biofilms are less susceptible to standard antibiotic therapies that are effective against planktonic bacteria. Standard procedure for the detection of microorganisms on the catheter tip is culture. However, viable but non-culturable cells (VBNCs) may be missed. The aim of this study was to evaluate the use of fluorescence in situ hybridization (FISH) as an indicator to visualize and quantify the effect of the antibiotics daptomycin and vancomycin on biofilms in situ. We established an in vitro catheter biofilm model of Staphylococcus epidermidis biofilms on polyurethane catheters. Biofilm activity was measured by FISH and correlated to colony forming units (CFU) data. Digital image analysis was used for quantification of total biofilm mass and the area of the FISH positive biofilm cells. FISH showed a pronounced effect of both antibiotics on the biofilms, with daptomycin having a significantly stronger effect in terms of both reduction of biofilm mass and number of FISH-positive cells. This supports the anti-biofilm capacity of daptomycin. Interestingly, neither antibiotic was able to eradicate all of the FISH-positive cells. In summary, FISH succeeded in visualization, quantification, and localization of antibiotic activity on biofilms. This technique adds a new tool to the arsenal of test systems for anti-biofilm compounds. FISH is a valuable complementary technique to CFU since it can be highly standardized and provides information on biofilm architecture and quantity and localization of survivor cells
Inferring kinetic parameters of oscillatory gene regulation from single cell time-series data
This work was supported by a Wellcome Trust Four-Year PhD Studentship in Basic Science to J.B. (219992/Z/19/Z) and a Wellcome Trust Senior Research Fellowship to N.P. (090868/Z/09/Z). C.M. was supported by a Sir Henry Wellcome Fellowship (103986/Z/14/Z) and University of Manchester Presidential Fellowship. M.R.âs work was supported by a Wellcome Trust Investigator Award (204832/B/16/Z).Gene expression dynamics, such as stochastic oscillations and aperiodic fluctuations, have been associated with cell fate changes in multiple contexts, including development and cancer. Single cell live imaging of protein expression with endogenous reporters is widely used to observe such gene expression dynamics. However, the experimental investigation of regulatory mechanisms underlying the observed dynamics is challenging, since these mechanisms include complex interactions of multiple processes, including transcription, translation and protein degradation. Here, we present a Bayesian method to infer kinetic parameters of oscillatory gene expression regulation using an auto-negative feedback motif with delay. Specifically, we use a delay-adapted nonlinear Kalman filter within a Metropolis-adjusted Langevin algorithm to identify posterior probability distributions. Our method can be applied to time-series data on gene expression from single cells and is able to infer multiple parameters simultaneously. We apply it to published data on murine neural progenitor cells and show that it outperforms alternative methods. We further analyse how parameter uncertainty depends on the duration and time resolution of an imaging experiment, to make experimental design recommendations. This work demonstrates the utility of parameter inference on time course data from single cells and enables new studies on cell fate changes and population heterogeneity.Publisher PDFPeer reviewe
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