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The Evolution of Dental Materials over the Past Century: Silver and Gold to Tooth Color and Beyond.
The field of dental materials has undergone more of a revolution than an evolution over the past 100 y. The development of new products, especially in the past half century, has occurred at a staggering pace, and their introduction to the market has been equally impressive. The movement has mostly come in the area of improved esthetics, marked by the gradual replacement of dental amalgam with dental composite and all-metal and porcelain-fused-to-metal indirect restorations with reinforced dental ceramics, all made possible by the rapid improvements in dental adhesive materials. This article covers the time course of dental materials development over the past century in which the Journal of Dental Research has been published. While there have been advances in nearly all materials used in the field, this article focuses on several areas, including dental amalgam, dental composites and light curing, dental adhesives and dental cements, ceramics, and new functional repair materials. A few short statements on future advances will be included at the end
Global environmental drivers of marine fish egg size
This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record.All data, R packages, and code (data manipulation, analyses, figures andtables) can be downloaded from our GitHub repositories (www.github.com/dbarneche/noaaErddap; www.github.com/dbarneche/envPred;https://github.com/dbarneche/fishEggSize)Aim
To test longâstanding theory on the role of environmental conditions (both mean and predictability) in shaping global patterns in the egg sizes of marine fishes.
Location
Global (50° S to 50° N).
Time period
1880 to 2015.
Major taxa studied
Marine fish.
Methods
We compiled the largest geoâlocated dataset of marine fish egg size (diameter) to date (nâ=â1,078 observations; 192 studies; 288 species; 242 localities). We decomposed sea surface temperature (SST) and chlorophyllâa time series into mean and predictability (seasonality and colour of environmental noise â i.e. how predictable the environment is between consecutive time steps), and used these as predictors of egg size in a Bayesian phylogenetic hierarchical model. We test four specific hypotheses based on the classic discussion by Rass (1941), as well as contemporary lifeâhistory theory, and the conceptual model of Winemiller and Rose (1992).
Results
Both environmental mean and predictability correlated with egg size. Our parsimonious model indicated that egg size decreases by c. 2.0âfold moving from 1 to 30â°C. Environments that were more seasonal with respect to temperature were associated with larger eggs. Increasing mean chlorophyllâa, from 0.1 to 1 mg/m3, was associated with a c. 1.3âfold decrease in egg size. Lower chlorophyllâa seasonality and reddened noise were also associated with larger egg sizes â aseasonal but more temporally autocorrelated resource regimes favoured larger eggs.
Main conclusions
Our findings support results from Rass (1941) and some predictions from Winemiller and Rose (1992). The effects of environmental means and predictability on marine fish egg size are largely consistent with those observed in marine invertebrates with feeding larvae, suggesting that there are important commonalities in how ectotherm egg size responds to environmental change. Our results further suggest that anthropogenically mediated changes in the environment will have profound effects on the distribution of marine life histories.Centre for Geometric Biolog
Dental restorations for oral rehabilitation â testing of laboratory properties versus clinical performance for clinical decision making *
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73116/1/j.1365-2842.2007.01812.x.pd
Development and validation of the Cambridge Multimorbidity Score
BACKGROUND: Health services have failed to respond to the pressures of multimorbidity. Improved measures of multimorbidity are needed for conducting research, planning services and allocating resources. METHODS: We modelled the association between 37 morbidities and 3 key outcomes (primary care consultations, unplanned hospital admission, death) at 1 and 5 years. We extracted development (n = 300 000) and validation (n = 150 000) samples from the UK Clinical Practice Research Datalink. We constructed a general-outcome multimorbidity score by averaging the standardized weights of the separate outcome scores. We compared performance with the Charlson Comorbidity Index. RESULTS: Models that included all 37 conditions were acceptable predictors of general practitioner consultations (C-index 0.732, 95% confidence interval [CI] 0.731-0.734), unplanned hospital admission (C-index 0.742, 95% CI 0.737-0.747) and death at 1 year (C-index 0.912, 95% CI 0.905-0.918). Models reduced to the 20 conditions with the greatest combined prevalence/weight showed similar predictive ability (C-indices 0.727, 95% CI 0.725-0.728; 0.738, 95% CI 0.732-0.743; and 0.910, 95% CI 0.904-0.917, respectively). They also predicted 5-year outcomes similarly for consultations and death (C-indices 0.735, 95% CI 0.734-0.736, and 0.889, 95% CI 0.885-0.892, respectively) but performed less well for admissions (C-index 0.708, 95% CI 0.705-0.712). The performance of the general-outcome score was similar to that of the outcome-specific models. These models performed significantly better than those based on the Charlson Comorbidity Index for consultations (C-index 0.691, 95% CI 0.690-0.693) and admissions (C-index 0.703, 95% CI 0.697-0.709) and similarly for mortality (C-index 0.907, 95% CI 0.900-0.914). INTERPRETATION: The Cambridge Multimorbidity Score is robust and can be either tailored or not tailored to specific health outcomes. It will be valuable to those planning clinical services, policymakers allocating resources and researchers seeking to account for the effect of multimorbidity
Return to driving after traumatic brain injury : a British perspective
Primary Objective: to identify current legal situation, and professional practice in assisting persons with traumatic brain injury (TBI) to return to safe driving after injury.
Methods and Procedures
A brief review of relevant literature, a description of the current statutory and quasi-statutory authorities regulating return to driving after TBI in the UK, and a description of the nature and resolution of clinical and practical dilemmas facing professionals helping return to safe driving after TBI. Each of the 15 UK mobility centres was contacted and literature requested; in addition a representative of each centre responded to a structured telephone survey.
Main Outcome and Results: The current situation in Great Britain is described, with a brief analysis of the strengths and weaknesses both of the current statutory situation, and also the practical situation (driving centres), with suggestions for improvements in practice.
Conclusion
Although brain injury may cause serious limitations in driving ability, previous drivers are not routinely assessed or advised regarding return to driving after TBI
An audit of acute oncology services: patient experiences of admission procedures and staff utilisation of a new telephone triage system.
OBJECTIVES: In 2010, St. James Institute of Oncology (Leeds, UK) created a new acute oncology service (AOS) consisting of a new admissions unit with a nurse-led telephone triage (TT) system. This audit cycle (March 2011 and June 2013) evaluated patient experiences of the reconfigured AOS and staff use of the TT system. METHODS: Patient views were elicited via a questionnaire and semi-structured interviews. The TT forms were analysed descriptively evaluating completion and data quality, reported symptoms and their severity and advice given (including admission rates). RESULTS: Patients (n = 40) reported high satisfaction with the new AOS. However, 56 % of patients delayed 2 days or more before contacting the unit. In 2011, 26 % of all the admitted patients were triaged via the TT system; 133 TT forms were completed. In June 2013, 49 % of the admitted patients were triaged; 264 forms were completed. The most commonly reported symptoms on the TT forms were pain, pyrexia/rigors/infection, diarrhoea, vomiting and dyspnoea. Half of the patients using the TT system were admitted (52 % in 2011, 49 % in 2013). CONCLUSIONS: Our audit provided evidence of successful implementation of the TT system with the number of TT forms doubling from 2011 to 2013. The new AOS was endorsed by patients, with the majority satisfied with the care they received
Cliophysics: Socio-political Reliability Theory, Polity Duration and African Political (In)stabilities
Quantification of historical sociological processes have recently gained
attention among theoreticians in the effort of providing a solid theoretical
understanding of the behaviors and regularities present in sociopolitical
dynamics. Here we present a reliability theory of polity processes with
emphases on individual political dynamics of African countries. We found that
the structural properties of polity failure rates successfully capture the risk
of political vulnerability and instabilities in which 87.50%, 75%, 71.43%, and
0% of the countries with monotonically increasing, unimodal, U-shaped and
monotonically decreasing polity failure rates, respectively, have high level of
state fragility indices. The quasi-U-shape relationship between average polity
duration and regime types corroborates historical precedents and explains the
stability of the autocracies and democracies.Comment: 4 pages, 3 figures, 1 tabl
The perception of affective touch in Parkinson's disease and its relation to small fibre neuropathy.
Affective touch sensation is conducted by a sub-class of C-fibres in hairy skin known as C-Tactile (CT) afferents. CT afferents respond maximally to gentle skin stroking at velocities between 1-10 cm/sec. Parkinson's disease (PD) is characterised by markedly reduced cutaneous C-fibres. It is not known if affective touch perception is influenced by C fibre density and if affective touch is impaired in PD compared to healthy controls. We predicted that perceived pleasantness to gentle stroking in PD would correlate with C afferent density and that affective touch perception would be impaired in PD compared to healthy controls. Twenty-four PD patients and 27 control subjects rated the pleasantness of brush stroking at an optimum CT stimulation velocity (3cm/sec) and two sub-optimal velocities (0.3cm/sec & 30cm/sec). PD patients underwent quantification of C-fibre density using skin biopsies and corneal confocal microscopy. All participants rated stroking velocity of 3cm/sec as the most pleasant with significantly lower ratings for 0.3cm/sec and 30cm/sec. There was a significant positive correlation between C-fibre density and pleasantness ratings at 3cm/sec and 30cm/sec but not 0.3cm/sec. Mean pleasantness ratings were consistently higher in PD patients compared to control subjects across all three velocities. This study shows that perceived pleasantness to gentle touch correlate significantly with C-fibre density in PD. The higher perceived pleasantness in PD patients compared to controls suggests central sensitisation to peripheral inputs, which may have been enhanced by dopamine therapy. This article is protected by copyright. All rights reserved
The effect of weight loss on lameness in obese dogs with osteoarthritis
This paper describes the effect of weight loss on lameness in obese dogs with osteoarthritis (OA). Fourteen obese client-owned dogs with clinical and radiographic signs of OA participated in an open prospective clinical trial. After a screening visit and a visit for collection of baseline data, the dogs were fed a restricted-calorie diet over a study period of 16Â weeks that incorporated six follow-up visits. At each visit, body weight and pelvic circumference were measured and severity of lameness was assessed using a numeric rating scale (NRS), a visual analogue scale (VAS) and kinetic gait analysis. This is the first study to assess both subjectively and objectively, the effect of weight loss alone on lameness in obese dogs with OA. The results indicate that body weight reduction causes a significant decrease in lameness from a weight loss of 6.10% onwards. Kinetic gait analysis supported the results from a body weight reduction of 8.85% onwards. These results confirm that weight loss should be presented as an important treatment modality to owners of obese dogs with OA and that noticeable improvement may be seen after modest weight loss in the region of 6.10 â 8.85% body weight
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