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Abstract In this work, near infrared (NIR) spectroscopy and multivariate data analysis were investigated as a fast and non-disruptive method to classify green coffee beans on continents and countries bases. FT-NIR spectra of 191 coffee samples, origin from 2 continents and 9 countries, were acquired by two different laboratories. Laboratory-independent Partial Least Square-Discriminant Analysis and interval PLS-DA models were developed by following a hierarchical approach, i.e. considering at first the continent and then the country of origin as discrimination rule. The best continent-based classification model was able to identify correctly more than 98% in prediction, whereas 100% of them were correctly predicted by the best country-based classification model. The inter-laboratory reliability of the proposed method was confirmed by McNemar test, since no significant differences (P > 0.05) were found. Furthermore, a validation was performed predicting the spectral test set of a laboratory using the model developed by the other one. Highlights • NIR Spectroscopy investigated to identify the geographical origin of green coffee. • Partial Least Square-Discriminant Analysis applied to build classification models. • Coffee origin for both continent and country was tested as discrimination parameter. • Variable selection applied to NIR spectra allowed improving the model performance. • Inter-laboratory comparison of the classification results was made by McNemar test. [ABSTRACT FROM AUTHOR]

Wind resource assessment is fundamental when selecting a site for wind energy projects. Wind is influenced by several environmental factors and understanding its spatial variability is key in determining the economic viability of a site. Numerical wind flow models, which solve physical equations that govern air flows, are the industry standard for wind resource assessment. These methods have been proven over the years to be able to estimate the wind resource with a relatively high accuracy. However, measuring stations, which provide the starting data for every wind estimation, are often located at some distance from each other, in some cases tens of kilometres or more. This adds an unavoidable amount of uncertainty to the estimations, which can be difficult and time consuming to calculate with numerical wind flow models. For this reason, even though there are ways of computing the overall error of the estimations, methods based on physics fail to provide planners with detailed spatial representations of the uncertainty pattern. In this paper we introduce a statistical method for estimating the wind resource, based on statistical learning. In particular, we present an approach based on ensembles of regression trees, to estimate the wind speed and direction distributions continuously over the United Kingdom (UK), and provide planners with a detailed account of the spatial pattern of the wind map uncertainty. [ABSTRACT FROM AUTHOR]

Abstract: In the hippocampal formation many neuromodulators are possibly implied in the synaptic plasticity such as the long-term potentiation (LTP) induced by high-frequency stimulation (HFS) of afferent fibers. We investigated the involvement of locally synthesized neural 17β-estradiol (nE2) in the induction of HFS-LTP in hippocampal slices from male rats by stimulating the Schaffer collateral fibers and recording the evoked field excitatory postsynaptic potential (fEPSP) in the CA1 region. We demonstrated that either the blockade of nE2 synthesis by the aromatase inhibitor letrozole, or the antagonism of E2 receptors (ERs) by ICI 182,780 did not prevent the induction of HFS-LTP, but reduced its amplitude by ∼60%, without influencing its maintenance. Moreover, letrozole and ICI 182,780 did not affect the first short-term post-tetanic component of LTP and the paired-pulse facilitation (PPF). These findings demonstrate that nE2 plays an important role in the induction phase of HFS-dependent LTP. Since the basal responses were not affected by the blocking agents, we suggest that the synthesis of nE2 is induced or enhanced by HFS through aromatase activation. In this context, the local production of nE2 seems to be a very effective mechanism to modulate the amplitude of LTP. [Copyright &y& Elsevier]

Abstract: In brainstem slices of young male rat, we investigated the influence of the neuroactive steroid testosterone (T) on the synaptic responses by analyzing the field potential evoked in the medial vestibular nucleus (MVN) by vestibular afferent stimulation. T induced three distinct and independent long-term synaptic changes: fast long-lasting potentiation (fLP), slow long-lasting potentiation (sLP) and long-lasting depression (LD). The fLP was mediated by 17β-estradiol (E2) since it was abolished by blocking the estrogen receptors (ERs) or the enzyme converting T to E2. Conversely, sLP and LD were mediated by 5α-dihydrotestosterone (DHT) since they were prevented by blocking the androgen receptors (ARs) or the enzyme converting T to DHT. Therefore, the synaptic effects of T were mediated by its androgenic or estrogenic metabolites. The pathways leading to estrogenic and androgenic conversion of T might be co-localized since, the occurrence of fLP under block of androgenic pathway, and that of sLP and LD under estrogenic block, were higher than those observed without blocks. In case of co-localization, the effect on synaptic transmission should depend on the prevailing enzymatic activity. We conclude that circulating and neuronal T can remarkably influence synaptic responses of the vestibular neurons in different and opposite ways, depending on its conversion to estrogenic or androgenic metabolites. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the effects of the neurosteroid 17β-estradiol (E2) on the evoked and spontaneous activity of rat medial vestibular nucleus (MVN) neurons in brainstem slices. E2 enhances the synaptic response to vestibular nerve stimulation in type B neurons and depresses the spontaneous discharge in both type A and B neurons. The amplitude of the field potential, as well as the excitatory post-synaptic potential (EPSP) and current (EPSC), in type B neurons, are enhanced by E2. Both effects are long-term phenomena since they outlast the drug washout. The enhancement of synaptic response is mainly due to facilitation of glutamate release mediated by pre-synaptic n-methyl-d-aspartate receptors (NMDARs), since the reduction of paired pulse ratio (PPR) and the increase of miniature EPSC frequency after E2 are abolished under D-(−)-2-amino-5-phosphonopentanoic acid (AP-5). E2 also facilitates post-synaptic NMDARs, but it does not affect directly α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) and group I-metabotropic glutamate receptors (mGluRs-I). In contrast, the depression of the spontaneous discharge of type A and type B neurons appears to depend on E2 modulation of intrinsic ion conductances, as the effect remains after blockade of glutamate, GABA and glycine receptors (GlyRs). The net effect of E2 is to enhance the signal-to-noise ratio of the synaptic response in type B neurons, relative to resting activity of all MVN neurons. These findings provide evidence for a novel potential mechanism to modulate the responsiveness of vestibular neurons to afferent inputs, and so regulate vestibular function in vivo. [Copyright &y& Elsevier]

Abstract: The Pisa plain contains a multilayered confined aquifer made up of Pleistocene sands and gravels. The groundwater from the wells tapping these horizons are generally of poor quality: they exhibit significant TDS, relatively high Cl content and considerable hardness. During geothermal prospecting of the Pisa plain, about 80 wells ranging in depth from 20 to 250 m were sampled, and both chemical (major ions) and isotope analyses were conducted. The data collected show that TDS is strongly influenced by HCO3 and Cl, and that a 3-component mixing process affects the groundwater’s chemical composition. The end members of this mixing process have been identified as: (a) diluted HCO3 meteoric water, which enters the plain mainly from the eastern and northern sides of the study area; (b) Cl-rich water, which largely characterizes the shallow sandy horizons of the multilayered aquifer system and has been attributed to the presence of seawater, as also suggested by δ18O data; and (c) SO4-rich groundwater, which is linked to the hot groundwater circulation within Mesozoic carbonate formations and, at first sight, seemed to affect only the gravelly aquifer. A SO4-rich water also contributes to the sandy aquifer; it probably enters the plain both laterally, from the margins of the Pisan Mountains and from depth, but promptly undergoes substantial SO4 reduction processes by bacteria. That such processes are at work is suggested both by the low SO4 and high HCO3 concentrations found in the well waters and by their C and S isotope compositions. The collected data have allowed zones with higher quality waters to be identified, which may someday be used for the local water supply. [Copyright &y& Elsevier]

A MW6.0 earthquake struck the Central Italian Apennines on August 24th 2016, followed by an important seismic sequence characterized by hundreds of aftershocks. The earthquake caused fatalities and partially destroyed several towns surrounding the epicentral area. In this context the Italian Centre for Seismic Microzonation and its applications was involved for the seismic characterization of the struck area. Using ambient vibrations spectral ratios at seventy-five sites and shear wave velocity profiles obtained through surface waves dispersion properties we assessed seismic site response properties in the Pretare and Piedilama villages located in the territory of Arquata del Tronto. The survey performed inside the valley in which the two villages are located set into evidence that the spectral ratios often show a predominant frequency ranging between 3.0 and 5.0 Hz or several peaks that can be related to some alternating layers with different velocities. Conversely, along the valley flanks, where the geological substratum outcrop, spectral ratios tend towards low amplitude values. The soft sediments inside the valley are characterized by shear wave velocity lower than 350 m/s, whereas the geological substratum has shear wave velocity ranging between 600 and 1200 m/s. The integrated interpretation of both geophysical and geological data, made possible to infer subsoil models of the investigated areas identifying the depth of the seismic bedrock and characterizing the buried morphology. [ABSTRACT FROM AUTHOR]

Abstract: Background: Data from previous study by our group suggest that in smoking women sex ratio of offspring is higher in newborns carrying ACP1⁎C allele than in other ACP1 genotypes, suggesting that differences observed among human population concerning the effect of smoking may depend in part on this genetic factor. Objectives: In order to further explore this issue we have studied another population and have analysed the relationship between sex ratio and ACP1⁎C gene frequency at population level. Methods: The analysis includes 719 consecutive births from Central Italy considered in a previous paper and 5510 consecutive births from Sardinia. Data from English and Japanese populations have also been considered in the analysis. Results: Among newborns not carrying ACP1⁎C there is a decrease of SR among the offspring of smoking mothers, while among newborns carrying the ACP1⁎C allele there is an increase of SR among the offspring of smoking mothers relative to non-smoking mothers. Considering Sardinian, Italian, English and Japanese population there is a linear positive relationship between ⁎C allele frequency and SR in smoking mothers. Conclusions: The present observation suggests an interaction between smoking and ACP1 regarding their effects on sex ratio, by which the presence of the ACP1⁎C allele appears to counteract the effect of smoking. This suggests that genetic background may modify the effects of toxic environmental factors on gamete production and functionality and/or on intrauterine survival. [Copyright &y& Elsevier]

Abstract: In this study we show that high frequency stimulation (HFS, 100Hz) of afferent fibers to the medial vestibular nucleus (MVN) can induce opposite long-term modifications of synaptic responses in the type B neurons depending upon the stimulation pattern. Long burst stimulation (LBS: 2s) and short burst stimulation (SBS: 0.55s) were applied with different burst number (BN) and inter-burst intervals (IBI). It results that both LBS and SBS can induce either N-methyl-d aspartate receptors (NMDARs)-mediated long-term potentiation (LTP) or long-term depression (LTD), depending on temporal organization of repetitive bursts. In particular, the IBI plays a relevant role in guiding the shift from LTP to LTD since by using both LBS and SBS LTP is induced by shorter IBI than LTD. By contrast, the sign of long-term effect does not depend on the mean impulse frequency evaluated within the entire stimulation period. Therefore, the patterns of repetitive vestibular activation with different ratios between periods of increased activity and periods of basal activity may lead to LTP or LTD probably causing different levels of postsynaptic Ca2+. On the whole, this study demonstrates that glutamatergic vestibular synapse in the MVN can undergo NMDAR-dependent bidirectional plasticity and puts forward a new aspect for understanding the adaptive and compensatory plasticity of the oculomotor responses. [Copyright &y& Elsevier]

Abstract: Using intracellular recordings, we investigated the effects of high frequency stimulation (HFS) of the primary vestibular afferents on the evoked excitatory postsynaptic potential (EPSP) and intrinsic excitability (IE) of type-A and type-B neurons of the medial vestibular nucleus (MVN), in male rat brainstem slices. HFS induces long-term potentiation (LTP) of both EPSP and IE, which may occur in combination or separately. Synaptic LTP is characterized by an increase in the amplitude, slope and decay time constant of EPSP and IE-LTP through enhancements of spontaneous and evoked neuron firing and of input resistance (Rin). Moreover, IE-LTP is associated with a decrease in action potential afterhyperpolarization (AHP) amplitude and an increase in interspike slope steepness (ISS). The more frequent effects of HFS are EPSP-LTP in type-B neurons and IE-LTP in type-A neurons. In addition, the development of EPSP-LTP is fast in type-B neurons but slow in type-A, whereas IE-LTP develops slowly in both types. We have demonstrated that activation of N-methyl-d aspartate receptors (NMDARs) is only required for EPSP-LTP induction, whereas metabotropic glutamate receptors type-1 (mGluR1) are necessary for IE-LTP induction as well as the full development and maintenance of EPSP-LTP. Taken together, these findings demonstrate that brief and intense activation of vestibular afferent input to the MVN neurons may provoke synaptic LTP and/or IE-LTP that, induced in combination or separately, may assure the different selectivity of the MVN neuron response enhancement to the afferent signals. [Copyright &y& Elsevier]