The prevalence and experience of oral diseases in Adelaide nursing home residents

The document attached has been archived with permission from the Australian Dental Association. An external link to the publisher’s copy is included.Background: The twenty-first century will see the evolution of a population of dentate older Australians with dental needs very different from those of older adults in past years. This study provided comprehensive information concerning oral disease prevalence in older South Australian nursing home residents. Methods: This paper presents cross-sectional baseline results. Results: Most of the 224 residents, from seven randomly selected nursing homes, were functionally dependent, medically compromised, cognitively impaired and behaviourally difficult older adults who presented many complex challenges to carers and to dental professionals. Two-thirds (66 per cent) were edentulous with many dental problems and treatment needs. Dentate residents had a mean of 11.9 teeth present, higher than previously reported. The prevalence and experience of coronal and root caries and plaque accumulation was very high in dentate residents; especially males, those admitted more than three years previously, those who ate fewer food types and those who were severely cognitively impaired. These residents had more retained roots, decayed teeth and missing teeth, and fewer filled teeth when compared with data for community-dwelling older adults. Conclusions: This study highlighted the poor oral health status of these nursing home residents and the great impact of dementia on their high levels of oral diseases.JM Chalmers, C Hodge, JM Fuss, AJ Spencer, KD Carte

Pointlike probes of superstring-theoretic superfluids

In analogy with an experimental setup used in liquid helium, we use a pointlike probe to study superfluids which have a gravity dual. In the gravity description, the probe is represented by a hanging string. We demonstrate that there is a critical velocity below which the probe particle feels neither drag nor stochastic forces. Above this critical velocity, there is power-law scaling for the drag force, and the stochastic forces are characterized by a finite, velocity-dependent temperature. This temperature participates in two simple and general relations between the drag force and stochastic forces. The formula we derive for the critical velocity indicates that the low-energy excitations are massless, and they demonstrate the power of stringy methods in describing strongly coupled superfluids.Comment: 17 pages, 2 figures, added a figure, a reference, and moved material to an appendi

Current concepts of the management of dental extractions for patients taking warfarin

The document attached has been archived with permission from the Australian Dental Association. An external link to the publisher’s copy is included.Background: Controversy has surrounded the correct management of patients therapeutically anticoagulated with warfarin who require dental extractions. The risk of bleeding must be weighed up against the risk of thromboembolism when deciding whether to interfere with a patient's warfarin regimen. An improved understanding of the importance of fibrinolytic mechanisms in the oral cavity has resulted in the development of various local measures to enable these patients to be treated on an outpatient basis. Methods: A review of the literature was undertaken. This was supplemented by the authors' clinical trials and extensive clinical experience with anticoagulated patients. Results: Various protocols for treating patients taking warfarin have been reviewed and summarized and an overview of the haemostatic and fibrinolytic systems is presented. A protocol for management of warfarinized patients requiring dental extractions in the outpatient setting is proposed. Conclusions: Patients therapeutically anticoagulated with warfarin can be treated on an ambulatory basis, without interruption of their warfarin regimen provided appropriate local measures are used.G Carter, AN Goss, JV Lloyd, R Tocchett

Astrobiological Complexity with Probabilistic Cellular Automata

Search for extraterrestrial life and intelligence constitutes one of the major endeavors in science, but has yet been quantitatively modeled only rarely and in a cursory and superficial fashion. We argue that probabilistic cellular automata (PCA) represent the best quantitative framework for modeling astrobiological history of the Milky Way and its Galactic Habitable Zone. The relevant astrobiological parameters are to be modeled as the elements of the input probability matrix for the PCA kernel. With the underlying simplicity of the cellular automata constructs, this approach enables a quick analysis of large and ambiguous input parameters' space. We perform a simple clustering analysis of typical astrobiological histories and discuss the relevant boundary conditions of practical importance for planning and guiding actual empirical astrobiological and SETI projects. In addition to showing how the present framework is adaptable to more complex situations and updated observational databases from current and near-future space missions, we demonstrate how numerical results could offer a cautious rationale for continuation of practical SETI searches.Comment: 37 pages, 11 figures, 2 tables; added journal reference belo

A Measurement of Rb using a Double Tagging Method

The fraction of Z to bbbar events in hadronic Z decays has been measured by the OPAL experiment using the data collected at LEP between 1992 and 1995. The Z to bbbar decays were tagged using displaced secondary vertices, and high momentum electrons and muons. Systematic uncertainties were reduced by measuring the b-tagging efficiency using a double tagging technique. Efficiency correlations between opposite hemispheres of an event are small, and are well understood through comparisons between real and simulated data samples. A value of Rb = 0.2178 +- 0.0011 +- 0.0013 was obtained, where the first error is statistical and the second systematic. The uncertainty on Rc, the fraction of Z to ccbar events in hadronic Z decays, is not included in the errors. The dependence on Rc is Delta(Rb)/Rb = -0.056*Delta(Rc)/Rc where Delta(Rc) is the deviation of Rc from the value 0.172 predicted by the Standard Model. The result for Rb agrees with the value of 0.2155 +- 0.0003 predicted by the Standard Model.Comment: 42 pages, LaTeX, 14 eps figures included, submitted to European Physical Journal

Measurement of the B+ and B-0 lifetimes and search for CP(T) violation using reconstructed secondary vertices

The lifetimes of the B+ and B-0 mesons, and their ratio, have been measured in the OPAL experiment using 2.4 million hadronic Z(0) decays recorded at LEP. Z(0) --> b (b) over bar decays were tagged using displaced secondary vertices and high momentum electrons and muons. The lifetimes were then measured using well-reconstructed charged and neutral secondary vertices selected in this tagged data sample. The results aretau(B+) = 1.643 +/- 0.037 +/- 0.025 pstau(Bo) = 1.523 +/- 0.057 +/- 0.053 pstau(B+)/tau(Bo) = 1.079 +/- 0.064 +/- 0.041,where in each case the first error is statistical and the second systematic.A larger data sample of 3.1 million hadronic Z(o) decays has been used to search for CP and CPT violating effects by comparison of inclusive b and (b) over bar hadron decays, No evidence fur such effects is seen. The CP violation parameter Re(epsilon(B)) is measured to be Re(epsilon(B)) = 0.001 +/- 0.014 +/- 0.003and the fractional difference between b and (b) over bar hadron lifetimes is measured to(Delta tau/tau)(b) = tau(b hadron) - tau((b) over bar hadron)/tau(average) = -0.001 +/- 0.012 +/- 0.008

Go-stimuli proportion influences response strategy in a sustained attention to response task

The sustained attention to response task (SART) usefulness as a measure of sustained attention has been questioned. The SART may instead be a better measure of other psychological processes and could prove useful in understanding some real-world behaviours. Thirty participants completed four Go/No-Go response tasks much like the SART, with Go-stimuli proportions of .50, .65, .80 and .95. As Go-stimuli proportion increased, reaction times decreased while both commission errors and self-reported task-related thoughts increased. Performance measures were associated with task-related thoughts but not taskunrelated thoughts. Instead of faster reaction times and increased commission errors being due to absentmindedness or perceptual decoupling from the task, the results suggested participants made use of two competing response strategies, in line with a response strategy or response inhibition perspective of SART performance. Interestingly, performance measures changed in a nonlinear manner, despite the linear Go proportion increase. A threshold may exist where the prepotent motor response becomes more pronounced, leading to the disproportionate increase in response speed and commission errors. This research has implications for researchers looking to employ the SAR

Parity-Violating Hydrodynamics in 2+1 Dimensions

We study relativistic hydrodynamics of normal fluids in two spatial dimensions. When the microscopic theory breaks parity, extra transport coefficients appear in the hydrodynamic regime, including the Hall viscosity, and the anomalous Hall conductivity. In this work we classify all the transport coefficients in first order hydrodynamics. We then use properties of response functions and the positivity of entropy production to restrict the possible coefficients in the constitutive relations. All the parity-breaking transport coefficients are dissipationless, and some of them are related to the thermodynamic response to an external magnetic field and to vorticity. In addition, we give a holographic example of a strongly interacting relativistic fluid where the parity-violating transport coefficients are computable.Comment: 39+1 page

Kinesin expands and stabilizes the GDP-microtubule lattice

Kinesin-1 is a nanoscale molecular motor that walks towards the fast-growing (plus) ends of microtubules, hauling molecular cargo to specific reaction sites in cells. Kinesin-driven transport is central to the self-organization of eukaryotic cells and shows great promise as a tool for nano-engineering1. Recent work hints that kinesin may also play a role in modulating the stability of its microtubule track, both in vitro2,3 and in vivo4, but the results are conflicting5,6,7 and the mechanisms are unclear. Here, we report a new dimension to the kinesin–microtubule interaction, whereby strong-binding state (adenosine triphosphate (ATP)-bound and apo) kinesin-1 motor domains inhibit the shrinkage of guanosine diphosphate (GDP) microtubules by up to two orders of magnitude and expand their lattice spacing by ~1.6%. Our data reveal an unexpected mechanism by which the mechanochemical cycles of kinesin and tubulin interlock, and so allow motile kinesins to influence the structure, stability and mechanics of their microtubule track