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Axonemal dynein motors are large multi-subunit complexes that drive ciliary movement. Cytoplasmic assembly of these motor complexes involves several co-chaperones, some of which are related to the R2TP co-chaperone complex. Mutations of these genes in humans cause the motile ciliopathy, Primary Ciliary Dyskinesia (PCD), but their different roles are not completely known. Two such dynein (axonemal) assembly factors (DNAAFs) that are thought to function together in an R2TP-like complex are DNAAF4 (DYX1C1) and DNAAF6 (PIH1D3). Here we investigate the

Ciliary motility is powered by a suite of highly conserved axoneme-specific dynein motor complexes. In humans, the impairment of these motors through mutation results in the disease primary ciliary dyskinesia (PCD). Studies in Drosophila have helped to validate several PCD genes whose products are required for cytoplasmic pre-assembly of axonemal dynein motors. Here we report the characterisation of the Drosophila orthologue of the less-known assembly factor DNAAF3. This gene, CG17669 (Dnaaf3), is expressed exclusively in developing mechanosensory chordotonal (Ch) neurons and the cells that generate spermatozoa, The only two Drosophila cell types bearing cilia/flagella containing dynein motors. Mutation of Dnaaf3 results in larvae that are deaf and adults that are uncoordinated, indicating defective Ch neuron function. The mutant Ch neuron cilia of the antenna specifically lack dynein arms, while Ca imaging in larvae reveals a complete loss of Ch neuron response to vibration stimulus, confirming that mechanotransduction relies on ciliary dynein motors. Mutant males are infertile with immotile sperm whose flagella lack dynein arms and show axoneme disruption. Analysis of proteomic changes suggest a reduction in heavy chains of all axonemal dynein forms, consistent with an impairment of dynein pre-assembly., Summary: DNAAF3 function as a dynein assembly factor for motile cilia is conserved in Drosophila.

This article proposes a hypermedia interface for writing and reading documents that include dynamic, interactive, abstract objects. Highly active and interactive documents supersede the passive ones we usually find in hypermedia systems. Although the work has its background in visual communication and story telling, it lends itself to any kind of domain modelling, shorthand systems, process descriptions, or formal representations of multimedia aspects of knowledge. It is a framework for dynamic abstract languages, rather than a single language as such. We present one specific example of such an interface: MUSLI (MUlti-Sensory Language Interface) and show how it may be used for interactive story telling.

The purpose of this study was to determine whether treatment with subantimicrobial dose doxycycline (SDD), 20 mg bid, exerted an antimicrobial effect on the microflora associated with adult periodontitis.Following the approval of the protocol and informed consent forms by the respective IRBs at the University of Florida and West Virginia University, 76 subjects with adult periodontitis were entered and randomly assigned to receive SDD or placebo. A split-mouth design was utilized, with each subject receiving subgingival scaling and root planing (SRP) in two quadrants immediately following baseline data collection, while the remaining two quadrants were left unscaled (non-SRP). Microbial samples were collected prior to treatment, after 3, 6, and 9 months of treatment, and after 3 months of no treatment. The samples were examined by microscopy and by enumeration on selective and non-selective media.All treatments resulted in statistically significant decreases in the proportions of spirochetes and motile rods (P0.05) and in an increase in the proportion of coccoid forms (P0.0001) relative to baseline. No between-treatment differences were detected between the SDD and placebo treatments in either the SRP or non-SRP design, with the exception of the small and large spirochetal groups. The spirochetal proportions present in the SDD group were significantly lower (P0.05) than the paired placebo group during the 9-month treatment and was preceded by a significant decrease (P0.01) in the proportion of microbiologic sample sites that bled on probing. No between- treatment differences were detected in any of the other microbial parameters.The microbial differences observed were attributed to the anticollagenase and anti-inflammatory properties of SDD and not to an antimicrobial effect.

Systems supporting new forms of communication and archiving of dynamic visual information have a range of potential applications, some of which are described in this paper on a conceptual basis. We present a visual language for dynamic (historic) maps, applications of pictorial lexicons, concepts for interactive support systems for assembly and repair, and a platform for abstract movies.

The purpose of this study was to determine the effects of periodontal treatment with a sustained-release, biodegradable gel containing 8.5% doxycycline on the anaerobic flora and on antibiotic susceptibility patterns associated with subgingival plaque and saliva.Forty-five subjects with adult periodontitis were entered into a parallel design, single-blind study of 6 months' duration. The subjects were randomized to receive either doxycycline treatment (n = 23) or oral hygiene instruction/reinforcement (n = 22). Saliva and subgingival plaque samples were collected prior to and at 7, 21, 91, and 182 days after initiation of treatment. The proportion of the cultivable flora resistant to 10 microg doxycycline/ml was determined relative to total anaerobic counts, and the 3 most predominant colony types resistant to doxycycline were individually enumerated. A representative of each was subcultured, identified to genus and species level, and tested for its susceptibilities to 6 antibiotics.A significant decrease (P0.01) in total anaerobic counts following doxycycline treatment caused a transient increase in the proportion, but not in the actual counts, of doxycycline-resistant bacteria recovered from both plaque and saliva at 7 and 21 days but not at 91 or 182 days. The same doxycycline-resistant taxa were recovered at all sample periods including baseline. Regardless of treatment, the isolates were similarly distributed and belonged to the same bacterial groups.Doxycycline treatment significantly reduced the anaerobic population in plaque but did not result in a change in either the number of resistant bacteria present or the acquisition of antibiotic resistance.

The history of hypermedia development resists reduction to a simple sequence of statements. Developments occurred in complex interrelations, and in many cases ideas cross-fertilised. Brilliant concepts too dependent on hardware that didn't materialise were abandoned — only to be rediscovered by other researchers. It is far from clear even where to start a history. Some of us may prefer to trace developments back from the present to the past. Others may wish to track all the side branches of failed development, seeking all the interesting whys and wherefores. Obviously this book should be hypertext! Even if, as I have chosen, we keep to a more or less traditional view of “developments”, it is still not easy to tell what name should be pulled out of the hat and placed on a timeline first — Bush, Engelbart, or Nelson, for example. However, several good surveys of hypermedia systems place Vannevar Bush first on the list [Nyce and Kahn, 1991, Conklin, 1987, Nielsen, 1990, Tomek et al., 1991].

In this chapter lecturing technologies past and present are considered and then several conjectures are made about future developments based on recent advances in hypermedia systems. The advantages and disadvantages of present day techniques are discussed, so that the ideas developed are soundly based on past experience. A single system is posited integrating technologies as diverse as multimedia presentations, computer-assisted learning, computer conferencing, distance teaching, and decision rooms.

The World Wide Web (WWW or simply the Web for short) is an Internet-wide distributed hypermedia information retrieval system [Liu et al., 1994] which provides access to a large universe of documents. The Web is certainly the most widely talked about networked information system existing today, and is definitely the largest hypermedia system in existence. Based on a typical client/server model, several widely used browsers are available (see Section 4.2.1).

In the previous sections we described the current version of the MUSLI editor/player prototype and we made a first attempt at describing a dynamic abstract visual language. However, we hope MUSLI will develop into not just a language but a whole multi-sensory environment. This hope is reflected in the name change from MUSIL (MUlti Sensory Information Language) to MUSLI (MUlti Sensory Language Interface)For example, as explained in Section 16.11, interactive, annotated and simultaneous movies should all be part of the environment. In Section 16.6.2 we also consider possible ways of “speed-reading” the wave forms of digitised speech

In Chapter 4 we discussed how the merging of multimedia and networking technologies has led to the spread of global hypermedia systems. In this chapter we discuss how the convergence of computer-based digital technology, analog technology (such as film, video, etc.), and networking could revolutionise our: — Everyday lives (see Section 5.4) — Work (see Section 5.5) — Lifelong learning (see Section 5.6)

As the timeline in the last chapter illustrates, fast-moving events were also taking place in the development of the Internet. But before we can discuss these advances we need to determine just what we mean by the “Internet” — or the “Net”, as many people call it. Is it: A great way of sending personal messages via electronic mail? A means of logging into remote machines? A collaborative tool supporting a wide range of multimedia? Or, as for increasing millions of users worldwide, is it something to be mined (or “surfed”) for a wealth of information, commercial opportunities, relaxation, and addictive fun?

Free will is such a basic tenet of everyday belief that we assign it to the depths of our subconsciousness. Freedom of choice is assumed to be a basic human right. People expect choice — maximum choice, comprehensive choice. Computer technologists are compulsively answering the demand; and each answer raises further expectations. We have interactive TV, choice of TV programs from a multi-windowed screen display, and personal computers that can double as TVs and video recorders. Meanwhile on our computer screens more and more windows are appearing, with an increasing number of dialog boxes. Computer-controlled movies are developing such a range of options that, even at this stage, we must remember that more is not always best. Confusion, haste, inertia, and mental repetitive strain injury are only some of the human factors that will necessitate real research to optimise choice.

Integrated learning environments, based on Web-based digital libraries, will allow remote access to resources from home, work, and learning centres, thus breaking down physical barriers [Marchionini and Maurer, 1995b].

Many of the important advances in hypermedia that we are discussing in this book are due to progress in data compression techniques (see Section 8.4) and in standardising network protocols (see Section 8.2.1).

This chapter could have been subtitled “Grappling with Medusa” — except that would give a wrong impression. We enjoy the Web. It can be enormous fun. Nevertheless, the analogy is apt since it is huge, multi-faceted, and writhing.

Hyperwave is a distributed hypermedia system developed at the Institute for Computer Science and Computer Supported New Media (IICM) at the Graz University of Technology in Graz, Austria. The principal architects are Prof. Hermann Maurer and Frank Kappe.

Any complexity to be understood, let alone conveyed, must be structured. It may be that the human brain needs it actually modelled as a structure, visual or conceptual. Moreover, anything new, particularly anything abstract, can be most comfortably met by meeting it in terms of something familiar. Computing, accepting all this, has had fun with metaphors. The concept of “navigating” is itself a metaphor. For multimedia presentations “travel” is only one of several available metaphors discussed in Section 9.2.

The statement “Millions of students take courses electronically” [Rossman, 1992] is no exaggeration. Even back in 1990, the National Technical University (NTU) in the US, for example, had more than 1,100 graduate students in their electronic learning programme, and most of those who completed the Masters programme said that they would not have been able to do so in any other way [Rossman, 1992].

Evolution in human-computer interface design has brought us a long way from the days when computers were all but dictators, when users obeyed enigmatic rules or risked ignominious crashes! Years of research and many trials involving users (willingly and unwillingly) have steadily improved computer interfaces to the point where today's operators are much more in control. However, we believe that the next few years will see another quiet revolution as the computer becomes more of a versatile supportive ally — a true Personal Assistant (PA for short).

Much of the confusion that surrounds electronic personal assistants arises from the open-ended complexity of their development. In this paper we categorise some of their more common uses before suggesting several thought-provoking extensions.

For 30 years repeated attempts have been made to use computers to support the teaching and learning process, albeit with only moderate success. Whenever major attempts failed, some seemingly convincing reasons were presented the for less than satisfactory results. In the early days cost or even lack of suitable equipment was blamed; after colour graphics computers started to be widespread, production costs of interactive and graphically appealing material were considered the main culprits; when modern multimedia authoring techniques did not change the situation either, the lack of personalized feed-back, of network support and the difficulty of producing high quality simulations were seen as main obstacles. With networks now offering excellent multimedia presentation and communication facilities the final breakthrough of computers as ultimate teaching and learning tool is (once more) predicted. And once more results will be disappointing if one crucial component is again overlooked: good courseware must give both guidance to students but also provide a rich variety of background material whenever such is needed. It is the main claim of this paper that the advent of sizeable digital libraries provides one of the most significant chances for computer based training ever. We will argue that such libraries not only allow the efficient production of courseware but also provide the extensive background reservoir of material needed in many situations.

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