Neonatal exposure to estradiol in female rats influences neuroactive steroid concentrations and behaviour in the adult rat

The gonadal steroids, in particular estradiol, exert an important action during perinatal period in the regulation of sexual dimorphism and neuronal plasticity, and in the growth and development of nervous system. Exposure of the developing female to estrogens during perinatal period may have long-lasting effects that are now regarded as “programming” the female neuroendocrine axis to malfunction in adulthood. The purpose of this study was to describe the effect of a single administration of a low dose (10 μg) of β-estradiol 3-benzoate (EB) to female rats on the day of birth on brain and plasma concentrations of the neuroactive steroid allopregnanolone, general behaviours and behavioral sensitivity to benzodiazepines. Neonatal administration of EB induces a dramatic reduction in the cerebrocortical and plasma levels of allopregnanolone and progesterone that were apparent in both juvenile (21 days) and adult (60 days). In contrast, this treatment did not affect 17β-estradiol levels. Female rats treated with β-estradiol 3-benzoate showed a delay in vaginal opening, aciclicity characterized by prolonged estrus, and ovarian failure. Given that allopregnanolone elicits anxiolytic, antidepressive, anticonvulsant, sedative-hypnotic effects and facilitates social behaviour, we assessed whether this treatment might modify different emotional, cognitive and social behaviours. This treatment did not affect locomotor activity, anxiety- and mood-related behaviours, seizures sensitivity and spatial memory. In contrast, neonatal β-estradiol 3-benzoate-treated rats showed a dominant, but not aggressive, behaviour and an increase in body investigation, especially anogenital investigation, characteristic of male appetitive behaviour. On the contrary, neonatal administration of β-estradiol 3-benzoate to female rats increases sensitivity to the anxiolytic, sedative, and amnesic effects of diazepam in adulthood. These results indicate that the marked and persistent reduction in the cerebrocortical and peripheral concentration of the neuroactive steroid allopregnanolone induced by neonatal treatment with β-estradiol 3-benzoate does not change baseline behaviours in adult rats. On the contrary, the low levels of allopregnanolone seems to be associated to changes in the behavioural sensitivity to the positive allosteric modulator of the GABAA receptor, diazepam. These effects of estradiol suggest that it plays a major role in pharmacological regulation both of GABAergic transmission and of the abundance of endogenous modulators of such transmission during development of the central nervous system

Detection And Characterization of Forest Harvesting In Piedmont Through Sentinel-2 Imagery: A Methodological Proposal

This study evaluated the effectiveness of Sentinel-2 (S2) as a tool for early detection and estimation of forest harvesting in the Piemonte Region, which can be used by the regional forest administration. The priority was the detection, at the regional scale, of annual forest cover changes with the following goals: i) mapping of irregular (in respect of the regional Forestry Regulation) forest cuts; ii) quantification of the intensity of the silvicultural interventions. Results are expected to support forest police controls.The proposed procedure is based on a supervised classification approach based on Random Forest algorithm. Accuracy of harvested areas detection proved to be high (overall accuracy 98%). Characterization of the occurred forest cuts was obtained computingthe local coefficient of variationof the normalized difference vegetation index (NDVI) after harvesting, that showed to be a good predictor of forest harvesting intensity

Temperature and masting control Norway spruce growth, but with high individual tree variability

Tree growth and reproduction are subject to trade-offs in resource allocation. At the same time, they are both influenced by climate. In this study, we combined long records of reproductive effort at the individual- (29 years), population- (41 years) and regional (up to 53 years) scale, and tree ring chronologies, to investigate the effects of climate and reproductive allocation on radial growth in an Alpine Norway spruce forest. Seed and cone production was highly variable between years (mean individual CV = 1.39, population CV = 1.19), but showed high reproductive synchrony between individuals (mean inter-tree correlation = 0.72). No long-term trend in reproductive effort was detected over four decades of observations. At the stand scale, cone production was dominated by a small number of individuals (\u201csuper-producers\u201d), who remained dominant over three decades. Individual tree growth responded positively to summer temperature, but the response to cone production varied between individual trees. Consequently, we found some evidence that mast years were associated with a divergence in growth between high and low cone producing individuals, and a decline in within-population growth synchrony. At the population level we found limited evidence of a relationship between growth and reproduction. Radial growth was lower than average in some mast years, but not in others. This was partly explained by summer temperature during the year of growth, with growth reductions restricted to mast years that coincided with colder than average summers. Regional mast records and tree ring chronologies provided some support to indicate that our results were consistent in other spruce stands, although the effect of mast years on growth appeared to vary between sites. Tree ring variation at the individual and population level, and between-tree growth synchrony are influenced by masting, and consequently dendrochronologists should consider both the occurrence of masting and the individual differences in reproductive effort when interpreting tree ring datasets. Our results also indicate that tree ring chronologies contain information to facilitate reconstruction of mast events, which will help address outstanding questions regarding the future response of masting to climate change