Potential of Diagnostic Microbiology for Treatment and Prognosis of Dental Caries and Periodontal Diseases

Most evidence suggests that only a finite number of bacteria are responsible for dental caries and periodontal diseases. This knowledge led to the development of microbial tests which can identify suspected pathogens. Current evaluation of the diagnostic power of microbial tests has shown that they have a low sensitivity and a low prognostic value. Despite these shortcomings, there are valid indications for microbiological-based diagnosis. Salivary microbial tests for the detection of mutans streptococci and lactobacilli may be useful, for example, in young children, oligosialic patients, and orthodontic patients. These tests can be used to monitor the success of chemopreventive measures or compliance with dietary recommendations. Microbial diagnosis may also be valuable in the treatment of early-onset periodontitis or in subjects who respond poorly to periodontal therapy. The use of microbial tests to monitor the efficacy of chemotherapy or mechanical treatment is of particular interest.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68094/2/10.1177_10454411960070030401.pd

Abstracting Remote Object Interaction in a Peer-2-Peer Environment

Leveraged by the success of applications aiming at the ``free'' sharing of data in the Internet, the paradigm of peer-to-peer (P2P) computing has been devoted substantial consideration recently. This paper presents an abstraction for remote object interaction in a P2P environment, called borrow/lend (BL). We present the principles underlying our BL abstraction, and its implementation in Java. We contrast our abstraction with established abstractions for distributed programming such as the remote method invocation or the tuple space, illustrating how the BL abstraction, obviously influenced by such predating abstractions, unifies flavors of these, but also how it captures the constraints specific to P2P environments

The Driving Philosophers

We introduce a new synchronization problem in mobile ad-hoc systems: the Driving Philosophers. In this problem, an unbounded number of driving philosophers (processes) access a round-about (set of shared resources organized along a logical ring). The crux of the problem is to ensure, beside traditional mutual exclusion and starvation freedom at each particular resource, gridlock freedom (i.e., cyclic waiting chain amongst processes). The problem captures explicitly the very notion of process mobility and the underlying model does not involve any assumption on the total number of (participating) processes or the use of shared memory, i.e., the model conveys the ad-hoc environment. We present a generic algorithm that solves the problem in a synchronous model. Instances of this algorithm can be fair but not concurrent, or concurrent but not fair. We derive the impossibility of achieving fairness and concurrency at the same time as well as the impossibility of solving the problem in an asynchronous model. We also conjecture the impossibility of solving the problem in an ad-hoc network model with limited-range communication

Distributed Subtyping

One of the most frequent operations in object-oriented programs is the "instanceof" test, also called the "subtyping" test or the "type inclusion" test. This test determines if a given object is an instance of some type. Surprisingly, despite a lot of research on distributed object-oriented languages and systems, almost no work has been devoted to the implementation of this test in a distributed environment. This paper presents the first algorithm to implement the "subtyping" test on an object received through the wire, without having to download the full code of the object type, nor to deserialize the object. We use a slicing technique that encodes a (multiple-subtyping) hierarchy using as little memory as the best known centralized implementation of the "subtyping" test. Our slicing technique is however different than centralized ones and allows for the dynamic addition of types without global reconfiguration. We convey the practicality of our algorithm through performance measures obtained from a fully distributed implementation of our algorithm which we experiment on standard Java hierarchies. In particular, we show that we can perform a subtyping test between 3 and 12 times faster than the code downloading approach without hampering the time taken for deserialization. Moreover, we require the same subtyping time as a string-based approach while reducing the encoding length by a factor of 50

Mobility Friendly Publish/Subscribe

This paper describes an event dissemination algorithm that implements a topic-based publish/subscribe abstraction in mobile ad-hoc networks (MANETs). Our algorithm relies on (1) the mobility of the processes and (2) the validity period of the events to ensure the reliability of the dissemination (under reasonable conditions) with a thrifty usage of the memory. The algorithm is inherently portable and does not assume any specific routing protocol. Old events are collected to save the memory and the energy consumption is, in some sense, related to the size of the event scope a subscriber is interested in. We give simulation results in different mobility models and highlight the advantages/drawbacks of our approach as well as we expose some interesting relations between validity periods and reliability

Data-Aware Multicast

This paper presents a multicast algorithm for peer-to-peer dissemination of events in a distributed topic-based publish-subscribe system, where processes publish events of certain topics, organized in a hierarchy, and expect events of topics they subscribed to. Our algorithm is ``data-aware'' in the sense that it exploits information about process subscriptions and topic inclusion relationships to build dynamic groups of processes and efficiently manage the flow of information within and between these process groups. This ``data-awareness'' helps limit the membership information that each process needs to maintain and preserves processes from receiving messages related to topics they have not subscribed to. It also provides the application with means to control, for each topic in a hierarchy, the trade-off between the message complexity and the reliability of event dissemination. We convey this trade-off through both analysis and simulation

OS Support for P2P Programming: a Case for TPS

Just like Remote Procedure Call (RPC) turned out to be a very effective OS ab-straction in building client-server applications over LANs, Type-based Publish-Sub-scribe (TPS) can be viewed as a high-level candidate OS abstraction for building Peer-to-Peer (P2P) applications over WANs. This paper relates our preliminary, though positive, experience of implementing and using TPS over JXTA: an analogous to the sockets for P2P infrastructures. We show that, at least for P2P applications with the Java type model, TPS provides a high-level programming support that ensures type safety and encapsulation, without hampering the decoupled nature of these applications. Furthermore, the loss of flex-ibility (inherent to the use of any high level abstraction) and the performance over-head, are negligible with respect to the simplicity gained by using TPS

Community-Aware Event Dissemination

This paper presents a distributed algorithm to disseminate events in a publish/subscribe system, where processes publish events of certain topics, organized in a hierarchy, and expect events of topics they subscribed to. Every topic defines a dynamic notion of ``community'', gathering the processes which publish on that topic or subscribe to it. Our algorithm is completely decentralized (no brokers), yet does not require from any process to ever receive, store or forward, events from a community it is not part of. We order the communities according to the topic inclusion relationships to efficiently manage the flow of information within, and between the communities, as well as limit the memory consumption of each process. Processes can control, for each of their communities, the trade-off between the message complexity and the reliability of event dissemination. We convey this trade-off through analysis, simulations and measurements obtained with a full implementation of our algorithm