Black Stain: studio clinico e microbiologico

Aim of the work. Objectives of the study are the following: quantify and identify microorganisms in the dental plaque of patients with black stain; test in vivo and in vitro efficacy of two mouthwashes; identify a protocol. Materials and methods. The research protocol included a clinical and a microbiological stage. 63 patients between 2 and 15 years with black stain were selected, then divided into three groups. In Group 1 (19 patients) no mouthwash was prescribed. In Group 2 (21 patients) was prescribed a fluoride mouthwash (Sodium Fluoride 0,05%). In Group 3 (23 patients) a chlorhexidine 0,12% mouthwash was prescribed. The microbiological stage provided analysis of pigmented plaque through bacterial count and identification tests and aura of inhibition on agar plate to evaluate the inhibitory power of the mouthwashes examined. Results. It was highlighted a strong decrease in index of pigmented plaque in Group 3 than Groups 1 and 2. The microbiological analysis revealed a decrease in bacterial count higher in Group 3 than Groups 1 and 2. The bacteria identified the most were Clostridia. The chlorhexidine mouthwash was more effective than fluorine mouthwash on bacterial growth. Conclusions. The use of mouthwash in conjunction with periodic specialist visits is essential to assist oral hygiene at home. It is assumed that the mouthwash with chlorhexidine 0,12% is the most effective in reducing black stain in vivo and in vitro

Is Diversity the Missing Link in Coastal Fisheries Management?

Fisheries management has historically focused on the population elasticity of target fish based primarily on demographic modeling, with the key assumptions of stability in environmental conditions and static trophic relationships. The predictive capacity of this fisheries framework is poor, especially in closed systems where the benthic diversity and boundary effects are important and the stock levels are low. Here, we present a probabilistic model that couples key fish populations with a complex suite of trophic, environmental, and geomorphological factors. Using 41 years of observations we model the changes in eastern Baltic cod (Gadus morhua), herring (Clupea harengus), and Baltic sprat (Sprattus sprattus balticus) for the Baltic Sea within a Bayesian network. The model predictions are spatially explicit and show the changes of the central Baltic Sea from cod-to sprat-dominated ecology over the 41 years. This also highlights how the years 2004 to 2014 deviate in terms of the typical cod–environment relationship, with environmental factors such as salinity being less influential on cod population abundance than in previous periods. The role of macrozoobenthos abundance, biotopic rugosity, and flatfish biomass showed an increased influence in predicting cod biomass in the last decade of the study. Fisheries management that is able to accommodate shifting ecological and environmental conditions relevant to biotopic information will be more effective and realistic. Non-stationary modelling for all of the homogeneous biotope regions, while acknowledging that each has a specific ecology relevant to understanding the fish population dynamics, is essential for fisheries science and sustainable management of fish stocks

Influence of soak time and fish accumulation on catches of reef fishes in a multispecies trap survey

Catch rates from fishery-independent surveys often are assumed to vary in proportion to the actual abundance of a population, but this approach assumes that the catchability coefficient (q) is constant. When fish accumulate in a gear, the rate at which the gear catches fish can decline, and, as a result, catch asymptotes and q declines with longer fishing times. We used data from long-term trap surveys (1990–2011) in the southeastern U.S. Atlantic to determine whether traps saturated for 8 reef fish species because of the amount of time traps soaked or the level of fish accumulation (the total number of individuals of all fish species caught in a trap). We used a delta-generalized-additive model to relate the catch of each species to a variety of predictor variables to determine how catch was influenced by soak time and fish accumulation after accounting for variability in catch due to the other predictor variables in the model. We found evidence of trap saturation for all 8 reef fish species examined. Traps became saturated for most species across the range of soak times examined, but trap saturation occurred for 3 fish species because of fish accumulation levels in the trap. Our results indicate that, to infer relative abundance levels from catch data, future studies should standardize catch or catch rates with nonlinear regression models that incorporate soak time, fish accumulation, and any other predictor variable that may ultimately influence catch. Determination of the exact mechanisms that cause trap saturation is a critical need for accurate stock assessment, and our results indicate that these mechanisms may vary considerably among species

Eight decades of adaptive changes in herring reproductive investment: the joint effect of environment and exploitation

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Debating the effectiveness of marine protected areas

Increasing the size and number of marine protected areas (MPAs) is widely seen as a way to meet ambitious biodiversity and sustainable development goals. Yet, debate still exists on the effectiveness of MPAs in achieving ecological and societal objectives. Although the literature provides significant evidence of the ecological effects of MPAs within their boundaries, much remains to be learned about the ecological and social effects of MPAs on regional and seascape scales. Key to improving the effectiveness of MPAs, and ensuring that they achieve desired outcomes, will be better monitoring that includes ecological and social data collected inside and outside of MPAs. This can lead to more conclusive evidence about what is working, what is not, and why. Eight authors were asked to write about their experiences with MPA effectiveness. The authors were instructed to clearly define “effectiveness” and discuss the degree to which they felt MPAs had achieved or failed to be effective. Essays were exchanged among authors and each was invited to write a shorter “counterpoint.” The exercise shows that, while experiences are diverse, many authors found common ground regarding the role of MPAs in achieving conservation targets. This exchange of perspectives is intended to promote reflection, analysis, and dialogue as a means for improving MPA design, assessment, and integration with other conservation tools

Spatio-temporal dynamics of a fish predator: Density-dependent and hydrographic effects on Baltic Sea cod population

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Comparative Evaluation Of The Efficacy Of Three Commercially Available Toothpastes On Dentin Hypersensitivity Reduction: An Eight-Week Clinical Study

OBJECTIVE: The objective of this eight-week, single-center, three-cell, double-blind, and randomized clinical study was to evaluate the dentin hypersensitivity reduction efficacy of three commercially available toothpastes: 1) Colgate Sensitive Pro-Relief Toothpaste (also marketed as elmex Sensitive Professional); 2) Sensodyne Rapid Relief Toothpaste; and (3) Crest Cavity Protection Toothpaste. METHODS: 150 subjects, having two teeth with tactile and air blast hypersensitivity, were assigned to one of the three study groups (50/group). Subjects were then asked to brush their teeth for one minute, twice daily, with the given toothpaste. The dentin hypersensitivity and oral tissues were evaluated at baseline, two weeks, four weeks, and eight weeks. Comparison of the treatment groups with respect to gender was conducted using a chi-square analysis, and with respect to age and baseline hypersensitivity scores was performed using the analysis of variance (ANOVA). Within-treatment effects were analyzed using the paired t-test, while the analysis of covariance (ANCOVA) was used to examine between-treatment effects. The post hoc Tukey test was performed for pair-wise comparisons. All statistical tests were two-sided using a significance level of alpha = 0.05. RESULTS: After two, four, and eight weeks of daily use of the products, all three groups showed a statistically significant reduction from baseline in tactile and air blast dentin hypersensitivity (p < 0.05). Colgate Sensitive Pro-Relief toothpaste produced a significant improvement in mean tactile and air blast dentin hypersensitivity scores, and was more effective than Sensodyne Rapid Relief toothpaste and Crest Cavity Protection toothpastes (p < 0.05). CONCLUSION: Colgate Sensitive Pro-ReliefToothpaste, used twice daily, significantly reduces dentin hypersensitivity, and is significantly more effective in reducing dentin hypersensitivity than Sensodyne Rapid Relief Toothpaste and Crest Cavity Protection Toothpaste

Polarization-dependent optomechanics mediated by chiral microresonators.

Chirality is one of the most prominent and intriguing aspects of nature, from spiral galaxies down to aminoacids. Despite the wide range of living and non-living, natural and artificial chiral systems at different scales, the origin of chirality-induced phenomena is often puzzling. Here we assess the onset of chiral optomechanics, exploiting the control of the interaction between chiral entities. We perform an experimental and theoretical investigation of the simultaneous optical trapping and rotation of spherulite-like chiral microparticles. Due to their shell structure (Bragg dielectric resonator), the microparticles function as omnidirectional chiral mirrors yielding highly polarization-dependent optomechanical effects. The coupling of linear and angular momentum, mediated by the optical polarization and the microparticles chiral reflectance, allows for fine tuning of chirality-induced optical forces and torques. This offers tools for optomechanics, optical sorting and sensing and optofluidics