Dental training system using haptic technology

In the U.K., dental students require to perform training and practice on real human tissues at the very early stage of their courses. Currently, the human tissues, such as decayed teeth, are mounted in a human head like physical model. The problems with these models in teaching are; (1) every student operates on tooth, which are always unique; (2) the process cannot be recorded for examination purposes and (3) same training are not repeatable. The aim of the PHATOM Project is to develop a dental training system using Haptic technology. This paper documents the project background, specification, research and development of the first prototype system. It also discusses the research in the visual display, haptic devices and haptic rendering. This includes stereo vision, motion parallax, volumetric modelling, surface remapping algorithms as well as analysis design of the system. A new volumetric to surface model transformation algorithm is also introduced. This paper includes the future work on the system development and research.

Investment in preventing and preparing for biological emergencies and disasters: social and economic costs of disasters versus costs of surveillance and response preparedness

Biological emergencies such as the appearance of an exotic transboundary or emerging disease can become disasters. The question that faces Veterinary Services in developing countries is how to balance resources dedicated to active insurance measures, such as border control, surveillance, working with the governments of developing countries, and investing in improving veterinary knowledge and tools, with passive measures, such as contingency funds and vaccine banks. There is strong evidence that the animal health situation in developed countries has improved and is relatively stable. In addition, through trade with other countries, developing countries are becoming part of the international animal health system, the status of which is improving, though with occasional setbacks. However, despite these improvements, the risk of a possible biological disaster still remains, and has increased in recent times because of the threat of bioterrorism. This paper suggests that a model that combines decision tree analysis with epidemiology is required to identify critical points in food chains that should be strengthened to reduce the risk of emergencies and prevent emergencies from becoming disasters.

When are ant-attractant devices a worthwhile investment? Vicia faba extrafloral nectaries and Lasius niger ants

Most studies aiming to determine the beneficial effect of ants on plants simply consider the effects of the presence or exclusion of ants on plant yield. This approach is often inadequate, however, as ants interact with both non-tended herbivores and tended Homoptera. Moreover, the interaction with these groups of organisms is dependent on ant density, and these functional relationships are likely to be non-linear. A model is presented here that segregates plant herbivores into two categories depending on the sign of their numerical response to ants (myrmecophiles increase with ants, non-tended herbivores decline). The changes in these two components of herbivores with increasing ant density and the resulting implications for ant-plant mutualisms are considered. It emerges that a wide range of ant densities needs to be considered as the interaction sign (mutualism or parasitism) and strength is likely to change with ant density. The model is used to interpret the results of an experimental study that varied levels of Aphis fabae infestation and Lasius niger ant attendance on Vicia faba bean plants. Increasing ant density consistently reduced plant fitness and thus, in this location, the interaction between the ants and the plant can be considered parasitic. In the Vicia faba system, these costs of ants are unlikely to be offset by other beneficial agents (e.g., parasitoids), which also visit extrafloral nectaries.

Actinomyces dentalis sp nov., from a human dental abscess

A previously undescribed filamentous, beaded, Gram-positive, rod-shaped bacterium was isolated from pus of a human dental abscess. Based on its cellular morphology end the results of biochemical testing the organism was tentatively identified as a member of the genus Actinomyces, but it did not correspond to any currently recognized species of this genus. Comparative 16S rRNA gene sequencing studies showed the bacterium represents a distinct subline within the genus Actinomyces, clustering within a group of species that includes Actinomyces bovis, the type species of the genus. Sequence divergence values of >8% with other recognized species within this phylogenetic group clearly demonstrated that the organism represents a hitherto unknown species. Based on biochemical and molecular phylogenetic evidence, it is proposed that the unidentified organism recovered from a dental abscess be classified as a novel species, Actinomyces dentalis sp. nov. The type strain is R18165(T) (= CCUG 48064(T) = CIP 108337(T)).

Actinomyces oricola sp. nov., from a human dental abscess

A previously undescribed Actinomyces-like bacterium was isolated from a human dental abscess. Based on its cellular morphology and the results of biochemical testing the organism was tentatively identified as a member of the genus Actinomyces, but it did not correspond to any currently recognized species of this genus. Comparative 16S rRNA gene sequencing studies showed the bacterium represents a hitherto unknown subline within the genus Actinomyces, clustering within a group of species, which includes Actinomyces bovis, the type species of the genus. Based on biochemical and molecular phylogenetic evidence, it is proposed that the unknown organism recovered from a dental abscess be classified as a new species, Actinomyces oricola sp. nov. The type strain of Actinomyces oricola is R5292(T) (=CCUG 46090(T)=CIP 107639(T)).

Direct investment in real estate

Momentum strategies have the potential to generate extra profits in private real estate markets. Tests of a variety of frequencies of portfolio reweighting identify periods of winner and loser performance. There are strong potential gains from momentum strategies that are based on prior returns over a 6- to 12-month period. Whether these gains are attainable for real-world investors depends on transaction costs, but some momentum strategies do produce net excess returns. The findings hold even if returns are unsmoothed to reflect underlying market prices.

Design and development of a haptic dental training system - hapTEL

This paper presents a novel design of a virtual dental training system (hapTEL) using haptic technology. The system allows dental students to learn and practice procedures such as dental drilling, caries removal and cavity preparation for tooth restoration. This paper focuses on the hardware design, development and evaluation aspects in relation to the dental training and educational requirements. Detailed discussions on how the system offers dental students a natural operational position are documented. An innovative design of measuring and connecting the dental tools to the haptic device is also shown. Evaluation of the impact on teaching and learning is discussed.

Real estate investment in global financial centers: risk, return and contagion

Global financial activity is heavily concentrated in a small number of world cities –international financial centers. The office markets in those cities receive significant flows of investment capital. The growing specialization of activity in IFCs and innovations in real estate investment vehicles lock developer, occupier, investment, and finance markets together, creating common patterns of movement and transmitting shocks from one office market throughout the system. International real estate investment strategies that fail to recognize this common source of volatility and risk may fail to deliver the diversification benefits sought.

Principal-agent issues in asset acquisition: UK institutions and their investment agents

This paper explores principal‐agent issues in the stock selection processes of institutional property investors. Drawing upon an interview survey of fund managers and acquisition professionals, it focuses on the relationships between principals and external agents as they engage in property transactions. The research investigated the extent to which the presence of outcome‐based remuneration structures could lead to biased advice, overbidding and/or poor asset selection. It is concluded that institutional property buyers are aware of incentives for opportunistic behaviour by external agents, often have sufficient expertise to robustly evaluate agents’ advice and that these incentives are counter‐balanced by a number of important controls on potential opportunistic behaviour. There are strong counter‐incentives in the need for the agents to establish personal relationships and trust between themselves and institutional buyers, to generate repeat and related business and to preserve or generate a good reputation in the market.