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International audience; Extension at slow to ultraslow midoceanic ridges is mostly accommodated by large detachment faults that expose mantle peridotite and/or lower-crustal rocks forming Oceanic Core Complexes (OCC). It is commonly accepted that OCC at slow spreading ridges form during the early stage of crystallization of the magmatic crust, when rocks are still close to their solidus temperature. This observation poses significant problems, as nucleation of detachment faults requires significant weakening, which instead is more easily obtained at low temperature. The RV Knorr cruise 210 Leg 5 on the 16.5°N OCC of the Mid-Atlantic Ridge recovered a narrow shear zone from the plutonic footwall of a mature detachment fault. Troctolites preserve a continuous transition from proto-mylonite to mylonite and ultramylonite equilibrated at temperature between 1100° and 900°C. EBSD analysis highlights increased phase mixing and weaker crystallographic fabrics in the ultra-mylonite with respect the mylonitic domains. While host troctolites were completely solidified at the deformation incoming, high-strain zones preserve evidences of syn-kinematic melt-related textures. Fabric patterns combined with plagioclase and olivine grain size piezometry and 1D rheological modeling indicate that the development of ultra-mylonite requires a switch from dislocation creep to melt-enhanced grain-boundary sliding. Activation of this mechanism was promoted by the occurrence of hydrous melt possibly produced by selective re-melting of plagioclase + Ti-pargasite microdomains in response to strain localization at subseismic strain rates. This study highlights the importance of hydrated magmatic phases to promote the onset of detachment faulting in OCC.

The post-collisional late Variscan magmatism of Sardinia-Corsica batholith attained a peak at about 290 Ma. In southern Sardinia, in the frontal part of the Variscan orogenic wedge, this magmatism is represented by three suites of granitoids, here defined as GS1, GS2 and GS3. GS1, GS2 and GS3 are slightly peraluminous and F-bearing granitoids; GS1 and GS3 granites show in addition a ferroan character, whereas GS2 rocks range from magnesian to ferroan, from granodiorites to leucogranites. From magnetic susceptibility data, GS1 and GS2 belong to the ilmenite series, whereas GS3 is a slightly oxidized rock-suite plotting on the ilmenite/magnetite series boundary. Each rock-suite shows distinctive characters, in terms of petrography, petrochemistry, rock associations, as well as metallogenic signature of the related fluids. The distinction among rock-suite types is made on the basis of both mafic and characteristic accessory minerals. Siderophyllitic dark mica as the only mafic phase, and accessory xenotime (Y) characterize the GS1 rocks; GS2 mineral associations include biotite ± hornblende + allanite + magnetite; GS3 rocks show an association of hastingsite + annite + allanite + magnetite. Chemical variations in the studied samples suggest different magmatic evolution of independent magmas. Pb, Sr and Nd isotopic data constrain the origin of magmas to lower crustal sources. Chemical composition of rocks and dark micas meet those of liquids experimentally obtained by low degrees of partial melting of different meta-igneous deep crustal sources, felsic for GS1 rock-types and more mafic for GS3 rock-types. GS1 intrusions show granophile-type (Sn-W-Mo) metallogenic signatures, very low magnetic susceptibility, and Nd model ages (referred to the Depleted Mantle - T DM ) of 2.3 Ga, coherent with a possible derivation from an old (early Proterozoic-Neoarchean), reduced and weathered basement, tectonically buried under Variscan covers. A definite deep crustal inhomogeneity is mirrored by GS3 granites, whose compositional and isotopic features indicate a younger (Nd model age: 1.6 Ga) tonalitic amphibolite source. Overall, the peculiarities of the studied granitoids suggest further compositional differences in the deep crust between southern and northern portion of the Sardinia-Corsica Variscan transect. Late Variscan lithospheric delamination appears as the most reliable mechanism that may have determined the high thermal regime that triggered partial melting of the crust. The close field association, at 290 Ma, of tholeiitic dike swarms and ferroan granitoids, supports this inference.

Skin colour was evaluated in summer in 91 Caucasian volunteers by means of a Minolta Chroma Meter CR-200, a colour analyser for measuring the reflective colour of surfaces by the tristimulus system. All the subjects were classified for skin type according to Fitzpatrick and minimal erythema dose determined. The skin colour of the buttock was taken to be the constitutive skin colour, and that of the cheek the facultative skin colour. It was found that the chromaticity of exposed skin was noticeably different from that of unexposed skin, being situated to the right of the latter in the chromaticity diagram. This means that skin that is usually exposed to the sun has a more intense red component, presumably because of increased vascularization. Exposed skin also showed lower reflectance (Y) or lightness (L*) than unexposed skin, probably because of pigmentation. Hence delta Y and delta L* give an approximate idea of the tanning capacity of each subject. delta Y and delta L* of skin types II and III were greater than delta Y and delta L* of skin type IV. This means that, with chronic exposure to sunlight, even fair skin can achieve a reasonable pigmentation. It is concluded that constitutive skin colour is a more meaningful parameter than facultative skin colour in assessing skin type.

We investigated whether spray-dried plasma (SDP) improved growth and health of piglets challenged with enterotoxigenic Escherichia coli K88 (ETEC). Forty-eight pigs weaned at 21 d (BW = 4.88 ± 0.43 kg) received one of four diets containing 6% SDP or fish proteins either non medicated (SDP-NM and FP-NM diets), or medicated with 0 or 250 mg/kg colistine + 500 mg/kg amoxycycline (SDP-M and FP-M diets), for 15 d. On d 4, pigs where orally challenged with ETEC. On d 15, eight pigs per dietary group were killed, blood and saliva were collected for analysis of K88 fimbriae specific immunoglobulin (Ig)-A, and jejunum was removed for villi preparation, histological analysis and cytokine expression. The presence or absence of K88 receptors (K88+ and K88- pigs respectively) was determined by villous adhesion assay. Effects of protein source on ADG (P = 0.04) and ADFI (P < 0.01) as well of medication on ADFI (P < 0.02) of all pigs were observed. In sacrified pigs, there was an effect of protein source on ADG (P = 0.03) and ADFI (P < 0.001), as well an interaction between medication and presence of K88 receptor (P = 0.02) for feed: gain ratio. Plasma K88 specific IgA were low in all K88- pigs and higher in K88+ pigs fed FP-NM as compared to all the other groups (P < 0.05), except SDP-M. An interaction was found among protein source, medication and presence of K88 receptors (P = 0.04 ). Saliva IgA were high in all pigs fed FP-NM and low in all the other pigs. Jejunum of pigs fed FP-NM showed some ulcerations, edema, and mild inflammatory cell infiltration (ICI). In pigs fed FP-M edema was reduced. Conversely, only a mild ICI was observed in pigs fed SDP-NM and SDP-M. Crypt depth was increased in K88+ pigs fed SDP-NM and an interaction between protein source and presence of K88 receptors was observed (P

The valuation of dietary solutions for weaning pigs is problematic. In field situations, an accurate control of replications is difficult and disturbing factors are hardly removed; in experimental farm, hygienic conditions are in general superior to practical farms. In the study of alternatives to in-feed antibiotics the challenge with K88 E.coli has been often proposed. The predisposition to this colibacillosis is, at least partially, genetically controlled and depends on the presence of intestinal receptors for the F4 fimbrial antigens of K88 E.coli...

ObjectivesCOVID-19 recurrent waves have ignited a debate on the role of seasonality in the contagion resurgence. Two opposite positions emerged. Those convinced of a sinusoidal seasonality recurring over one-year period driven by climate. Those believing that a fluctuation of the outbreaks repeats without limits, in the absence of control measures. We studied the series of daily confirmed SARS-CoV-2 cases in 30 different countries (February 2020 - December 2021), investigating the hypothesis of whether seasonal and geographic variations may guide the pandemic trajectory.MethodsWe chose 30 countries from different geographies and climates. With a discrete Fourier transform, we performed a spectral analysis of the series of the daily SARS-CoV-2 infections, looking for peaks in the frequency spectrum that could correspond to a recurrent cycle of a given length. This analysis allows to question whether COVID-19 outbreaks have an observable seasonal periodicity.ResultsAll the 30 investigated countries see the recurrence of at least one COVID-19 wave, repeating over a period in the range 3 - 9 months, with a peak of magnitude at least half as large as that of the highest peak ever experienced since the beginning of the pandemic until December 2021. We also computed the distance in days between the two higher peaks in each country, and then we averaged those values over the 30 countries, yielding a mean of 190 days (SD 100). This suggests that outbreaks may repeat with cycles of different lengths, without a precisely predictable seasonality of one year.ConclusionOur findings suggest that COVID-19 outbreaks are likely to occur worldwide, with cycles of repetition of variable lengths. Our Fourier analysis with 30 different countries has not found evidence in favor of a seasonality that recurs over one-year period, solely or with a precisely fixed periodicity.DesignNot ApplicableSettingNot ApplicableParticipantsNot ApplicableInterventionsNot ApplicablePrimary and Secondary Outcome MeasuresNot ApplicableArticle SummaryStrengths and Limitations of this StudyThe use of a discrete Fourier transform offers the advantage of a temporal decomposition of the time series of the daily SARS-COV-2 cases, allowing to explore the temporal relationships among recurrent outbreaks.Analyzing for each country the various repetition cycles of the outbreaks, along with their magnitudes, represents an appropriate method to question the assumption of a seasonal “rise and fall” structure of COVID-19 assumed to recur, almost exclusively, based on a one-year long period.We have made inferences about the seasonality of COVID-19 from a purely observational study. The problem has been avoided to quantify, precisely, the role attributable to various climatic factors or control measures, like temperatures or vaccination.To take advantage of a natural experiment, the time series of the number of daily SARS-CoV-2 cases were subjected to a discrete Fourier transform without resorting to any form of correction/normalization. The SARS-CoV-2 outbreak (started in December 2021) has not been included in this study as the progression of this wave is still ongoing.This analysis presents a natural limitation in time as the pandemic has been in progress so far, for only two years. The Fourier uncertainty principle may render the results at low frequencies somewhat uncertain given this extremely short time domain.

While the role played by air pollution and meteorological conditions on SARS-Cov-2 transmission is still subject of a scientific controversy, we have extended our analysis on this association by studying the impact of particulate on the beginning of the second wave in Emilia-Romagna (Italy), in the period October-November 2020. Again, we found many clues in favour of this hypothesis, with new results that shed a particular light on the time varying effect of the particulate on the virus spread. Specifically, we found a strong magnitude of correlation between the PM10 particulate and CoViD-19 infections, peaking at 6–7th day lags for contagions, while this magnitude drops to a medium level value with 9–11th day lags. This is of special interest, if we consider that the specialized literature suggests a median CoViD-19 incubation period of almost 6days before that infected people display symptoms.

Supervised Machine Learning (ML) requires that smart algorithms scrutinize a very large number of labeled samples before they can make right predictions. And this is not always true either. In our experience, in fact, a neural network trained with a huge database comprised of over fifteen million water meter readings had essentially failed to predict when a meter would malfunction/need disassembly based on a history of water consumption measurements. With a second step, we developed a methodology, based on the enforcement of a specialized data semantics, that allowed us to extract only those samples for training that were not noised by data impurities. With this methodology, we re-trained the neural network up to a prediction accuracy of over 80%. Yet, we simultaneously realized that the new training dataset was significantly different from the initial one in statistical terms, and much smaller, as well. We had reached a sort of paradox: We had alleviated the initial problem with a better interpretable model, but we had changed the replicated form of the initial data. To reconcile that paradox, we further enhanced our data semantics with the contribution of field experts. This has finally led to the extrapolation of a training dataset truly representative of regular/defective water meters and able to describe the underlying statistical phenomenon, while still providing an excellent prediction accuracy of the resulting classifier. At the end of this path, the lesson we have learnt is that a human-in-the-loop approach may significantly help to clean and re-organize noised datasets for an empowered ML design experience.

While Europe was beginning to deal with the resurgence of COVID-19 due to the Delta variant, the European football championship took place from 11 June to 11 July 2021. We studied the inversion in the decreased/increased rate of new SARS-COV-2 infections in the countries of the tournament, investigating the hypothesis of an association. Using a Bayesian piecewise regression with a Poisson generalized linear model, we looked for a changepoint in the timeseries of the new SARS-COV-2 cases of each country, expecting it to appear not later than two to three weeks after the date of their first match. The two slopes, before and after the changepoint, were used to discuss the reversal from a decreasing to an increasing rate of the infections. For 17 out of 22 countries (77%) the changepoint came on average 14.97 days after their first match (95% CI 12.29–17.47). For all those 17 countries, the changepoint coincides with an inversion from a decreasing to an increasing rate of the infections. Before the changepoint, the new cases were decreasing, halving on average every 18.07 days (95% CI 11.81–29.42). After the changepoint, the cases begin to increase, doubling every 29.10 days (95% CI 14.12–9.78). This inversion in the SARS-COV-2 case rate, which happened during the tournament, provides evidence in favor of a relationship.

We have tried to provide an answer to the question whether a collection of satellite images, with notable archaeological sites, is informative enough to instruct a deep learning model that discovers new archaeological sites, well before archaeologists venture out in the field. Convolutional neural networks and satellite images in the visible light range were employed to detect sites in the Iraqi region of Qadisyah. The preliminary results we achieved are interesting yet not still fully convincing. The AUC value we got is near 70%, while more interesting findings have come from the idea to map the numerical predictions into heat-maps, revealing the regions where a site can lie. Several motivations can explain this controversial output. Not least is the fact that our model was instructed to learn archaeological sites of a very different form and size.

Many data scientists are currently pointing out that the amount of Machine Learning (ML) research that will cross into practice will depend, not just on the ability of the specialized algorithms used to scrutinize positive/negative examples, but also on the quality of the data exploited for training those algorithms. Our experience, while training a neural network with a huge dataset comprised of over fifteen million water meter readings, confirms such conjecture. In this paper, we report on the actions we took to extrapolate from that database just those data that could correctly represent the complex statistical phenomenon in play. With an adequate re-organization of those data, we got an interesting, yet controversial, result. On the one hand, we improved the accuracy on the prediction when a water meter fails/needs disassembly based on a history of water consumption measurements, thus making smarter a meter maintenance process; on the other hand, all this came with the paradox of a (statistical) transformation of the initial dataset: while we alleviate a problem with a restructured and better interpretable data model, we simultaneously change the replicated form of those data.

In this paper, using Reddit, we investigated on the efficacy of using an AI-based mood analysis methodology to understand how the prescription of different prenatal diagnostic tests (invasive vs non-invasive), and their corresponding outcomes, may have an impact onto the mood of parents-to-be. We found an interesting causal relationship between tests and mood that deserves a deeper comprehension by means of healthcare professionals. We have also demonstrated that combining AI-based dialogue analysis methodologies with advanced statistics may bring to a smart model, suitable for transforming a large amount of empirical data into correct medical interpretations.

Baby formula acidification can be used to reduce diarrhea. Calcium formate is a dietary acidifier frequently used in animal weaning diets; it is also a source of available calcium. Gastric acidification reduces gastrin release and hydrochloric acid (HCl) secretion. To study the medium-term effects on fundic gastric mucosa, we fed weaning pigs control diets or diets supplemented with free or fat-protected calcium formate. We evaluated the following: 1) the number of HCl-secreting parietal cells, by immunohistochemistry using an antibody against H(+)/K(+)-ATPase; 2) the number of enteroendocrine cells immunohistochemically stained with chromogranin A (CGA), somatostatin, and histamine (HIS); and 3) the expression of the H(+)/K(+)-ATPase gene, by real-time RT-PCR in the oxyntic mucosa. Cells co-staining for CGA and HIS were defined as enterochromaffin-like (ECL) cells. Pigs fed calcium formate had fewer parietal cells and a lower expression of the H(+)/K(+)-ATPase gene than the controls (P < 0.05). This reduction did not occur in pigs fed fat-protected calcium formate. Somatostatin immune-reactive cells were also more numerous in pigs fed free calcium formate than in controls (P < 0.05). The number of ECL cells was not affected. Using covariance analysis, the number of parietal cells explained part of the differences in the expression of H(+)/K(+)-ATPase gene (positive correlation, r = 0.385, P < 0.01), and excluded the statistical significance of the diet. In the future, the effects on the oxyntic mucosa should be checked when the diet supplemented with calcium formate is discontinued. Furthermore, a reduction in the number of parietal cells could impair the absorption of vitamin B-12 due to a reduced secretion of the intrinsic factor by these cells.

64 weaned pigs (24d-old), were fed a control diet or a control plus 1% thymol diet, with or without Salmonella typhimurium challenge. Thymol reduced feed intake but did not affect significantly the final body weight after 29d of trial. Salmonella did not affect the performances. Body temperature was lower in the thymol group before, but also 1d after challenge, when Salmonella increased the values more in unsupplemented pigs. Fecal excretion of S. typhimurium in challenged pigs was not changed by the diet. The thymol group had a higher concentration of immunoglobulin (Ig) in serum before the challenge, but after there was an interaction between diet and challenge. The diet and the challenge did not affect saliva parameters, and ATPase gene expression in the fundic gastric mucosa. Thymol increased the number of parietal cells for 100 μm depth of oxintic gland. In conclusion the important supplementation with thymol reduced the intake, but not performance in the medium period. Some factors of the gut barrier were positively influenced. Salmonella challenge did not reduce significantly the performance of the weaned piglet.

In a full factorial design (4 diets X challenge, Yes/No), 72 weaning pigs were assigned to one of the diets: Control; experimental diets, obtained with the addition of 2 g/kg free sodium butyrate (fNaB), or 0.6 g/kg fat-protected sodium butyrate (pNaB), or 2 g/kg INVE-NutriAd commercial mixture (Mix, based on 75 g/kg protected butyrate). Oral challenge with Escherichia coli K88 was done on 2/3 of pigs on d 7. Pigs were slaughtered on d 13. The mortality in challenged pigs, tended to be higher in control group (50.0 %) than in the three supplemented groups (23.5%). Growth tended to be increased averagely by the supplements (P = 0.100) after the challenge, that also significantly reduced growth. In general the diet did not affect the fecal shedding of Escherichia coli and Lactobacilli, the K88-specific IgA activity in blood, the morphology of oxyntic mucosa and the expression of H+/K+-ATPase gene. The supplementations tended to increase villous length of jejunum (P = 0.101). On the whole, growth, villous height and surviving rate can be positively affected either when the supplementation is done by free butyrate, by protected butyrate or by the special Inve Nutri-Ad product and these effects are distributed both on pigs infected or not with Escherichia coli K88.