Search

BackgroundThis study aims to show the long-time stability of straight and tilted implants loaded immediately with a provisional resin bridge followed by a definitive prosthodontic rehabilitation in edentulous jaws despite difficult hygiene conditions postoperatively.ResultsThis study included the participation of 23 patients and the restoration of 170 dental implants in 32 edentulous jaws. Patient data was analyzed from the start of treatment with a minimum follow-up period of 6 years in order to determine long-term implant success rates. However, the age of patients at time of surgery significantly affected the BOP to the detriment of younger patients (median 62 years old).ConclusionAlthough there was a higher risk of implant failure due to general disease, all the implants in this study survived successfully. As a replacement for a complete dental arch, the reduced number of implants in combination with the avoidance of augmentations reduces treatment costs. The immediate fixed prosthetic restoration of edentulous jaws thus represents a reliable therapeutic alternative to a two- to three-stage procedure. Optimized aftercare including professional teeth cleaning (PTC) (at least twice a year) can minimize the anamnestic effect of smoking, diabetes mellitus, and osteoporosis on BOP and possible bone loss.

Die meisten Infektionen, die eine Schwangere durchmacht, bleiben ohne Folgen fur Mutter und Kind. Andererseits konnen dieselben Erreger die Mutter, den Schwangerschaftsablauf und/oder die Gesundheit des Kindes beeintrachtigen, indem sie zu erhohter Morbiditat, zur Infektion des Embryos oder Feten, zu Abort, Totgeburt, Missbildungen, Entwicklungsstorungen, Krankheiten des Neugeborenen oder chronischen Infektionen mit unterschiedlichem Ausgang fuhren. Diese viralen, bakteriellen und anderen Infektionen sind zwar nur mit 5–10% an den Gesamtursachen fur Abort, Totgeburt und kindliche Schadigung beteiligt, ihnen kommt aber wegen der moglichen Infektionsprophylaxe und -therapie eine besondere Bedeutung zu.

In this chapter, we present an overview of the Tremellomycetes, a basal group in the Agaricomycotina that contains Cystofilobasidiales, Filobasidiales, Holtermanniales, Trichosporonales, and Tremellales, and some possibly related taxa (Bartheletia, Wallemia). Tremellomycetes comprise mostly dimorphic species, which have both a monokaryotic yeast stage and a dikaryotic filamentous stage. The majority of species that produce macroscopically visible, mostly gelatinous basidiomes belong to the Tremellales; some belong to the Holtermanniales (Holtermannia) or Filobasidiales (Syzygospora). Only a yeast stage is known for many Tremellomycetes, which has hampered a coherent phylogenetic classification. Micromorphology in the Tremellomycetes is diverse, with basidial types ranging from longitudinally septate to transversely or obliquely septate to holobasidiate. We review the state of knowledge of the morphology, ultrastructure, and ecology of Tremellomycetes and discuss their phylogenetic relationships, complemented by a comprehensive molecular phylogenetic analysis, including most of the species for which sequence data are available.

We show in this paper that the isolation characteristic of system virtualization can be bypassed by the use of a cache timing attack. Using Bernstein’s correlation in this attack, an adversary is able to extract sensitive keying material from an isolated trusted execution domain. We demonstrate this cache timing attack on an embedded ARM-based platform running an L4 microkernel as virtualization layer. An attacker who gained access to the untrusted domain can extract the key of an AES-based authentication protocol used for a financial transaction. We provide measurements for different public domain AES implementations. Our results indicate that cache timing attacks are highly relevant in virtualization-based security architectures, such as trusted execution environments.

Twitter is a relatively recent phenomenon, and the common metric of success is number of followers. Because people use Twitter in a myriad different ways, and the presence of spammers, it is necessary to discover new ways of quantifying success. In this paper, we explore the nature of engagement on Twitter and find the traditional follower/following network to be meaningless in this regard. Building on previous research, we define engagement in terms of interactions using the @ notation, and visualize this as a graph. We then apply clique finding techniques to this graph, to extract a sub-graph of the most important connections in a user’s immediate network.

On Twitter, hashtags allow users to gather around a topic in a digital space, something that has been common since early IRC and internet chat rooms. However there are three important differences when gathering on Twitter: persistence, invitation, and device independence. In this paper, we search for patterns in these digital spaces through the use of visualization to explore the temporal rhythms that emerge.

Current research directions in Semantic Peer-to-Peer(SP2P) networks are evolving to combine two complementary technologies: Peerto-Peer(P2P) networks and formally-structured information, Ontology. SP2P systems incorporate several additional features not present in P2P networks. However, the current SP2P research efforts have generated many and diverse realizations and architectures. This diversity in implementation and architecture in turn has led to an ambiguity and incompatibility in defining domain abstracts and concepts and as such has hampered progress in this area. For instance, system comparison as well as their translation into practical implementation have been hindered. In this work, we describe a reference model for SP2P systems in an effort to model the emerging decentralized computing paradigm in a generic and high level abstraction. The potential contribution of the reference model to the advancement of the current SP2P systems spans various areas. These include: 1) an establishment of common terminologies for the domain. This leads to better understanding and communication among members of the community. 2) providing guidelines for comparison among individual systems. Individual systems could be compared with each other in terms of their compliance with the generic model, and their implementation of the generic features.

The development of modern Web 2.0 applications is increasingly characterized by the involvement of end users with typically limited programming skills. In particular, an emerging practice is the development of web mashups, i.e., applications based on the composition of contents and functions that are accessible via the Web. In this article, we try to explain the ingredients that are needed for end users to become mashup developers, namely adequate mashup tools and lightweight development processes, leveraging on the users' capability to innovate. We also describe our own solution, the DashMash platform, an example of end-user-oriented mashup platform that tries to fill the gaps that typically prevent end users from fully exploiting the mashup potential as innovation instruments. DashMash offers an intelligible, easy-to-use composition paradigm that enables even inexperienced users to compose own mashups. As confirmed by a user-centric experiment, its paradigm is effective and increases the satisfaction of the end users.

This part of this volume contains the proceedings of the First International Workshop on Enabling Service Business Ecosystems (ESBE'08), held on December 01, 2008 in Sydney, Australia, in conjunction with the International Conference on Service Oriented Computing (ICSOC) 2008. Today, services are used as a core component or utility of business operations and offer programmatic interfaces to applications to exploit these services. The majority of attention on service oriented systems has been contemplated on its related technical standards and technology integration. However, many of today's available services are not considered as providing relevant business value as their use by third-party clients have unclear terms and conditions with unknown risk. The trend of software transforming to the service oriented paradigm demands a new way of business model reassurance to manage services operation, deployment, and longevity in the context of business ecosystems.

Wang tiles are unit size squares with colored edges. By using a fixed-point theorem a la Kleene for tilings we give novel proofs of classical results of tilings problems' undecidability by way of diagonalization on tilings (made possible by this theorem). Then, we present a general technique to construct aperiodic tile sets, i.e. , tile sets that generate only aperiodic tilings of the plane. Our last construction generalizes the notion of self-simulation and makes possible the construction of tile sets that self-simulate via self-similar tilings, showing how complex the self-simulation can be.

Modularity of an open source software code base has been associated with community growth, incentives for voluntary contribution, and a reduction in free riding. As a theoretical construct, it links open source software to other domains of research, including organization theory, the economics of industry structure, and new product development; however, measuring the modularity of an open source software design has proven difficult, especially for large and complex systems. Building on previous work on Design Structure Matrices (DSMs), this paper describes two contributions towards a method for examining the evolving modularity of large-scale software systems: (1) an algorithm and new modularity metric for comparing code bases of different size; and (2) evolution analysis of Apache Tomcat to illustrate the insights gained from this approach. Over a ten-year period, the modularity of Tomcat continually increased, except in three instances: with each major change to the architecture or implementation, modularity first declined, then increased in the subsequent version to fully compensate for the decline.

Recently, many organizations invested in Business Process Management Systems (BPMSs) in order to automate and monitor their processes. Business Activity Monitoring is one of the essential modules of a BPMS as it provides the core monitoring capabilities. Although the natural step after process monitoring is process improvement, most of the existing systems do not provide the means to help users with the improvement step. In this paper, we address this issue by proposing an aspect-oriented framework that allows the impact of changes to business processes to be explored with what-if scenarios based on the most appropriate process redesign patterns among several possibilities. As the four cornerstones of a BPMS are process, goal, performance and validation views, these views need to be aligned automatically by any approach that intends to support automated improvement of business processes. Our framework therefore provides means to reflect process changes also in the other views of the business process. A health care case study presented as a proof of concept suggests that this novel approach is feasible.

Wang tiles are unit size squares with colored edges. In this paper, we approach one aspect of the study of tilings computability: the quest for a universal tile set. Using a complex construction, based on Robinson's classical construction and its different modifications, we build a tile set μ (pronounced ayin ) which almost always simulates any tile set. By way of Banach-Mazur games on tilings topological spaces, we prove that the set of μ -tilings which do not satisfy the universality condition is meager in the set of μ -tilings.

To tile consists in assembling colored tiles on Z2 while respecting color matching. Tilings, the outcome of the tile process, can be seen as a computationmodel. In order to better understand the global structure of tilings, we introduce two topologies on tilings, one a la Cantor and another one a la Besicovitch. Our topologies are concerned with the whole set of tilings that can be generated by any tile set and are thus independent of a particular tile set. We study the properties of these two spaces and compare them. Finally, we introduce two infinite games on these spaces that are promising tools for the study of the structure of tilings.

Technologies based on aspect-orientation and multi-dimensional separation of concerns have given software engineers tools to better encapsulate concerns throughout the software lifecycle. Separated concerns must be composed, even during early lifecycle phases, to obtain an overall system understanding. Concern composition languages therefore must be expressive, scalable, and intuitive. Otherwise, gains achieved by concern separation are offset by the complexity of the composition rules. This paper focuses on a composition language for the requirements modeling phase and, in particular, on composition of concerns described with use cases or scenarios. We propose that existing composition techniques (such as before and after advices from AOP) are insufficient for requirements model composition because they do not support all composition rules frequently required for use cases or scenarios. Furthermore, composition rules for a modeling language should be visual and use the same notation as the modeling language. This paper presents Aspect-oriented Use Case Maps (AoUCM) and evaluates its flexible, expressive, and exhaustive composition technique. Moreover, the composition rules are expressed in the same notation already used for UCMs. The usefulness and necessity of our composition rules are demonstrated through examples modeled with the jUCMNav tool.

Once aspects have been identified during requirements engineering activities, the behavior, structure, and pointcut expressions of aspects need to be modeled unobtrusively at the requirements level, allowing the engineer to seamlessly focus either on the behavior and structure of the system without aspects or the combined behavior and structure. Furthermore, the modeling techniques for aspects should be the same as for the base system, ensuring that the engineer continues to work with familiar models. This paper describes how, with the help of Use Case Maps (UCMs), scenario-based aspects can be modeled at the requirements level unobtrusively and with the same techniques as for non-aspectual systems. Use Case Maps are a visual scenario notation under standardization by the International Telecommunication Union. With Use Case Maps, aspects as well as pointcut expressions are modeled in a visual way which is generally considered the preferred choice for models of a high level of abstraction.

Tropos is an agent-oriented development methodology based on knowledge-level concepts (such as actor, goal, and the dependency between actors) with a particular focus on requirements analysis. This paper presents a pattern language for guiding developers, especially those without previous Tropos experience, through the various design challenges faced when using Tropos. The patterns format allows us to motivate the modelling constructs, justify each of the development stages, and address specific modelling problems. These patterns are inter-linked in such a way that developers can navigate from higher-level to lower-level patterns as they apply the Tropos methodology. The paper has two goals: to motivate the use of agent-oriented methodologies such as Tropos to a wider set of developers, and to provide guidance for the different development activities of the Tropos methodology. Specifically, we focus on the development stages, models, and diagrams of Tropos. The patterns in this paper cover the early and late requirements analysis stages.

The need for semantic interoperability between ontologies in a peer-to-peer (P2P) environment is imperative This is because, by definition participants in P2P environment are equal, autonomous and distributed For example, the synthesis of concepts developed independently by different academic researchers, different research labs, various emergency service departments and, hospitals and pharmacies, just to mention a few, are an assertive request for cooperation and collaboration among these independent peers In this work we are looking at issues that enable us to build a robust semantic consensus to solve the interoperability problem among heterogeneous ontologies in P2P networks To achieve a robust semantic consensus we focus on three key issues: i semantic mapping faults, ii consensus construction iii fault-tolerance All these three issues will be further elaborated in this paper, initial steps to address theses issues will be described and fault-tolerant semantic mapping research directions will be further identified.

Agent Oriented Software Engineering and security patterns have been proposed as suitable paradigms for the development of secure information systems. However, so far, the proposed solutions are focused on one of these paradigms. In this paper we propose an agent oriented security pattern language and we discuss how it can be used together with the Tropos methodology to develop secure information systems. We also present a formalisation of our pattern language using Formal Tropos. This allows us to gain a deeper understanding of the patterns and their relationships, and thus to assess the completeness of the language.

Despite their apparent simplicity, Web applications are surprisingly difficult to develop, if our aim is to build applications that behave correctly under regular conditions as well as adverse circumstances like out-of-order requests and race conditions. In this paper, we describe our experiences deriving customer-oriented acceptance tests for Web applications by modeling the essential capabilities of such applications with Use Case Maps (UCMs). Abstract test purposes are generated from a UCM model using scenario definitions and scenario extraction tools. These test purposes are then converted interactively to test cases in the FitNesse acceptance testing framework, which is popular in the Extreme Programming (XP) community. The test cases are used to validate a Web application where several typical but non-trivial bugs were planted. Challenges in the automation of the process are also discussed.

Web services promise to allow businesses to adapt rapidly to changes in the business environment, and the needs of different customers. The rapid introduction of new web services into a dynamic business environment can lead to undesirable interactions that negatively impact service quality and user satisfaction. In previous work, we have shown how to model such interactions between web services as feature interactions, and reason about undesirable side-effects of web service composition. In this paper we present the results of subsequent research on a classification of feature interactions among web services. Such a classification is beneficial as we can then search for ways of detecting and resolving each class of feature interaction in a generic manner. To illustrate the interactions we use a fictitious e-commerce scenario.

The advantages of the agent-based approach are still not widely recognized outside the agent research community. We believe that there is a need for guidelines that summarize the key benefits of the agent approach to non-agent experts. Agent patterns can provide that guidance. The agent community has already started to use patterns for describing best practices of agent design. However, these patterns tend to pre-suppose that the decision to follow an agent approach has already been made. In this paper we present a pattern language – a set of patterns that build on each other – as a starting point for more specific agent pattern languages. It documents the forces – the drivers, and design trade- offs – involved in agent-based design, and a set of generic patterns that apply to all agent systems. These patterns introduce and motivate the concepts of agent society, roles, common vocabulary, delegation and mediation. The paper illustrates the application of these patterns with a case study on information agents for filtering news.

The advantages of the agent-based approach are still not widely recognized outside the agent research community. In this paper we use patterns as a way of motivating the use of agents. Patterns have proven to be an effective means for communicating design knowledge, describing not only solutions, but also documenting the context and motivation for applying these solutions. The agent community has already started to use patterns for describing best practices of agent design. However, these patterns tend to pre-suppose that the decision to follow an agent approach has already been made. Yet, as this author has experienced on many occasions, that is usually far from a given. There is a need for guidelines that summarize the key benefits of the agent approach, and serve as a context for more specific agent patterns. Our response to this need is a pattern language – a set of patterns that build on each other – that introduces the concepts of agent society, roles, common vocabulary, delegation, and mediation. We also argue that authors of agent patterns should aim to organize their patterns in the form of pattern languages, and present a template for pattern languages for agents.

Newcomers always appear on the scene when an industry is undergoing radical upheaval, and niches and ‘white space’ appear within the altered structures that have either been overlooked by the old hands or which they were unable to fill. With their business models based on product and/or process innovations, newcomers not only adapt themselves to the market but in their turn also shape its structures. However not all newcomers arrive on the scene with real innovations, and even the media industry has seen a lot of newcomers come and go. The more innovative the business model — it has been observed — the greater the opportunity for securing a promising place in the media landscape. Yet innovations alone are not enough. The key to success is satisfying customer needs in a profitable way, needs that are changing at least as fast as the mass medium Internet is growing.

Over the last few years, prospects in the media industry did not look too bad. A wide array of external — economical and technological — factors spurred tremendous growth in the industry. Between 1995 and 2001 alone, German media offerings in the radio sector grew by 12%, popular magazines by 29% and the TV sector even shot up by 112% due to the proliferation of private stations. Technological progress enabled the digitalization of content. Increasing coverage by the Internet facilitated digital content syndication online and consequently spurred heightened expectations. Positive forecasts in the late 90s were accompanied by an extremely positive development in advertising revenues in practically all media.

In the past, traditional media companies’ typical value chains were marked by more or less high vertical integration of the single value-adding steps — generation, aggregation and lastly, distribution of media content. The reason for this was especially the strictly media-linked content. Each strategic decision on organic and inorganic growth or on partnerships was aligned from production to marketing on to the specifics of the relevant medium or respectively restricted by the medium.

Much of agent system development to date has been done ad hoc. These problems limit the extent to which “industrial applications” can be built using agent technology, as the building blocks, reusable techniques, approaches and architectures have either not been exposed or have not yet been fully elaborated. In the mid 80’s, supporters of object-oriented technology had similar problems. However, with the aid of software patterns, objects have provided an important shift in the way developers successfully build applications today. In this paper, after describing an agent pattern’s generic format, we identify a set of software patterns for agent coordination.

Eine wesentliche Anforderung an heutige CAD-Systeme ist die transparente Integration mehrerer Werkzeuge. Wesentlicher Bestandteil eines Schemas zur Werkzeugintegration ist ein Kontrollmechanismus fur die sich dynamisch andernde Laufzeit-Konfiguration des Systems. Als Losungsansatz wird hier ein Protokoll zur Konfigurationskontrolle und seine Implementierung in einem Lisp-Dialekt vorgestellt. Est is dies auch eine Fallstudie zum objekt-orientierten Programmieransatz und zum Client-Server Paradigma.