Pain threshold values during periodontal probing: assessment of maxillary incisor and molar sites

Probing pain threshold (PPT) assessments were conducted in the facial and oral sulci of maxillary central incisors and first molars of 10 periodontally healthy adults. All subjects were systemically healthy, free of pain, and reported no current medication usage. A computer-linked electronic probe, modified to deliver steadily increasing forces up to 200 grams, was used to collect the data. The system contained a subject operated "off-switch" which, upon activation, signaled the computer to record the subject's PPT. Assessments of each subject's PPTs were conducted on 3 separate occasions at 7-day intervals. Results indicated that the facial sulci of the incisors were the most pain sensitive. They displayed a mean PPT of 50.9 +/- 26.6 grams. The oral sulci of the incisors exhibited a mean PPT of 76.5 +/- 45.2 grams. Facial and oral sulci of the molars evidenced mean PPT values of 102.6 +/- 52.1 grams and 113.5 +/- 51.3 grams, respectively. These data suggest that sulci associated with incisor teeth are nearly twice as pain sensitive as sulci associated with molar teeth. In addition, facial sulci are significantly more pain sensitive than oral sulci. Data did not indicate a visit effect nor a side-of-mouth effect on PPT values.     

The "new science" of wetland restoration

The intricate workings of natural wetlands are slowly yielding their secrets to scientists applying a number of experimental approaches.     

Free energy perturbation approach for the rational engineering of the antibody for human hepatitis B virus

HzKR127 is the humanized monoclonal antibody effective for the neutralization of human hepatitis B virus. By means of the free energy perturbation (FEP) calculations based on molecular dynamic (MD) simulations, we examine the mutation-induced variations in the energetic and structural features associated with the interactions between HzKR127 and its antigen. N58A, Y96A, D97A, and D97A/Y102A mutants of HzKR127 are taken in account in this study for which the experimental data for relative efficacies with respect to the wild-type antibody are available. The results of the present MD-FEP simulation studies show that in order to enhance the affinity for the antigen, the engineering of HzKR127 should be made in such a way as to promote the dynamic stability of the overall protein conformation and that of the translational motion of the antigen in the antibody-antigen complex. The relative binding free energies of the four mutant antibodies obtained from MD-FEP calculations compare pretty well with the experimental mutagenesis data with the associated squared correlation coefficient of 0.96. This indicates that MD-FEP calculations may serve as a useful computational tool for rational antibody engineering. Discussed in detail are the differences in the structural features of antibody-antigen interactions between the wild-type and the mutant antibodies that are responsible for the change in binding affinities for the antigen.     

Credible sets for risk ratios in over-reported two-sample binomial data using the double-sampling scheme

We consider point and interval estimation for risk ratios based on two independent samples of binomial data subject to false positive misclassification. For such data it is well known that the model is unidentifiable. We consider incorporating training data obtained by using a double-sampling scheme to make the model identifiable. In this identifiable model, we propose a Bayesian method to make statistical inferences. In particular, we derive an easy-to-implement closed-form algorithm for drawing from the posterior distributions. The algorithm is illustrated using a real data example and further examined via Monte Carlo simulation studies.     

Distraction 'on the buses': a novel framework of ergonomics methods for identifying sources and effects of bus driver distraction

Driver distraction represents a significant problem in the public transport sector. Various methods exist for investigating distraction; however, the majority are difficult to apply within the context of naturalistic bus driving. This article investigates the nature of bus driver distraction at a major Australian public transport company, including the sources of distraction present, and their effects on driver performance, through the application of a novel framework of ergonomics methods. The framework represents a novel approach for assessing distraction in a real world context. The findings suggest that there are a number of sources of distraction that could potentially distract bus drivers while driving, including those that derive from the driving task itself, and those that derive from the additional requirements associated with bus operation, such as passenger and ticketing-related distractions. A taxonomy of the sources of bus driver distraction identified is presented, along with a discussion of proposed countermeasures designed to remove the sources identified or mitigate their effects on driver performance.     

Prophylactic efficacy of tilmicosin for bovine respiratory tract disease

The prophylactic administration of injectable tilmicosin for pneumonia in weaned beef calves was investigated in 1,806 animals. Comparisons were made among calves receiving an "on-arrival" injection of tilmicosin, calves receiving a single injection of long-acting oxytetracycline, and calves receiving no prophylaxis. Morbidity and mortality attributable to pneumonia, morbidity and mortality attributable to all causes, and case fatality were significantly lower in the group of calves that received tilmicosin, compared with calves that received long-acting oxytetracycline and calves that received no prophylactic antibiotic. Mean time to initial pneumonia treatment was significantly extended in calves that received prophylaxis, compared with those that received no antibiotic on arrival at the feedlot. Calves that received tilmicosin gained significantly more weight than calves that received oxytetracycline. Calves that were not treated for pneumonia during the trial period gained significantly more weight than did those calves that were treated for pneumonia regardless of experimental group. The majority of mortalities were attributable to fibrinous pneumonia (31/34). Important bacterial isolates (Pasteurella spp, Haemophilus somnus, Actinomyces pyogenes) obtained at necropsy did not have resistance to tilmicosin in association with administration of tilmicosin as prophylaxis for pneumonia. However, bacterial resistance to trimethoprim/sulfonamide and to oxytetracycline were commonly found in these postmortem isolates.     

CQI and technology: partnership drives improvement

CQI plus technology equals increased financial success, according to Parkview Episcopal Medical Center. For this Pueblo, Colo., community hospital, the results of this equation are impressive--time saved, a motivated workforce and last but not least, more revenue.