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Childhood trauma is a major precipitating factor in psychiatric disease. Emerging data suggest that stress susceptibility is genetically determined, and that risk is mediated by changes in limbic brain circuitry. There is a need to identify markers of disease vulnerability, and it is critical that these markers be investigated in childhood and adolescence, a time when neural networks are particularly malleable and when psychiatric disorders frequently emerge. In this preliminary study, we evaluated whether a common variant in the brain-derived neurotrophic factor (BDNF) gene (Val66Met; rs6265) interacts with childhood trauma to predict limbic gray matter volume in a sample of 55 youth high in sociodemographic risk. We found trauma-by-BDNF interactions in the right subcallosal area and right hippocampus, wherein BDNF-related gray matter changes were evident in youth without histories of trauma. In youth without trauma exposure, lower hippocampal volume was related to higher symptoms of anxiety. These data provide preliminary evidence for a contribution of a common BDNF gene variant to the neural correlates of childhood trauma among high-risk urban youth. Altered limbic structure in early life may lay the foundation for longer term patterns of neural dysfunction, and hold implications for understanding the psychiatric and psychobiological consequences of traumatic stress on the developing brain.

Context: Low-abrasive polishing powders such as glycine (GLY) or erythritol (ERY) are used for subgingival air polishing. GLY was reported to possibly affect the dentin surface, while this is unclear for ERY. Aims: This in vitro study aimed to evaluate the substance loss from the dentin surface by air polishing with ERY at different settings for pressure (PR), distance (DI), and angulation of the spray jet to the surface (AJ). Materials and Methods: The in vitro testing was performed on smooth human root dentin surfaces. In 18 groups with 10 specimens each, ERY was applied with constant water supply for 5 s without moving the handpiece at the following settings: PR minimum (min), medium (med), and maximum (max); DI at 1, 3, and 5 mm; and 45° or 90° AJ. The substance loss was measured as defect depth (DD) using three-dimensional (3D)-laser profilometry. ANOVA with Bonferroni correction and α = 0.05 were used for statistical analysis. Results: The DD was statistically significantly higher at a DI of 1 mm compared to a DI of 5 mm for the respective groups of the same PR and AJ (P < 0.05). For DI 1 mm, max PR, and AJ 90°, the maximum loss of substance amounted DD of 117 ± 43 μm. The minimal loss of substance occurred at minimal PR, 45° AJ, and a DI of 5 mm (15 μm × 20 μm). DD related directly with the parameters PR and AJ and inversely with DI. The highest influence on DD was proven for DI. Conclusions: Slight loss of dentin might occur during air polishing with ERY depending on DI, PR and AJ. The setting influences the amount of dentin loss.

Wild ungulates are increasing in several regions of the world, recolonizing the empty niche left by previous livestock systems. Due to their important role as ecosystem engineers, wild ungulates can modify and change vegetation structure, as well as modulate soil ecological processes, affecting the remaining components of communities and posing new management challenges. Several studies have evaluated the effects of wild ungulates on other guilds, but the results are taxonomically biased. Thus, our goal is to synthesise the overall effects of wild ungulates on smaller mammals on a broad scale.Due to the complexity of assessing these impacts throughout the ecological network, we focused on mammals since they occupy different trophic levels and are key taxa in food webs. We conducted a review of the documented effects of wild ungulates on the guild's abundance of mammals with less than 10 kg, which revealed a gap in the literature regarding how higher trophic levels respond to wild ungulate disturbances. Using a hierarchical meta‐analytic approach, we assessed, on a subset of articles, whether the presence of wild ungulates affects the guild of small mammals and whether these effects were associated with biome, wild ungulates' body mass and foraging strategy, and small mammals' body mass.A quantitative meta‐analysis was possible only for small mammals (Rodentia/Soricomorpha/Macroscelidea <1 kg) and revealed that their abundance tended to decrease with increasing abundance of wild ungulates. The magnitude of this impact, however, was modulated by body mass, being greater for larger small mammals than for smaller ones.The impacts of wild ungulates might result in changes in the abundance of small mammals through direct and indirect pathways. Our results motivate a more holistic evaluation of rewilding projects and the correct assessment of the effects concerning wild ungulates' reintroductions. [ABSTRACT FROM AUTHOR]