3,281 research outputs found
Processi evolutivi, innovativi e ricerca nel sistema nazionale delle comunità per minorenni.
No full textDirect replacement of antibodies with molecularly imprinted polymer (MIP) nanoparticles in ELISA - development of a novel assay for vancomycin
No full textA simple and straightforward technique for coating microplate wells with molecularly imprinted polymer nanoparticles (nanoMIPs) to develop ELISA type assays is presented here for the first time. NanoMIPs were synthesized by a solid phase approach with immobilized vancomycin (template) and characterized using Biacore 3000, dynamic light scattering and electron microscopy. Immobilization, blocking and washing conditions were optimized in microplate format. The detection of vancomycin was achieved in competitive binding experiments with a HRP-vancomycin conjugate. The assay was capable of measuring vancomycin in buffer and in blood plasma within the range 0.001-70 nM with a detection limit of 0.0025 nM (2.5 pM). The sensitivity of the assay was three orders of magnitude better than a previously described ELISA based on antibodies. In these experiments nanoMIPs have shown high affinity and minimal interference from blood plasma components. Immobilized nanoMIPs were stored for 1 month at room temperature without any detrimental effects to their binding properties. The high affinity of nanoMIPs and the lack of a requirement for cold chain logistics make them an attractive alternative to traditional antibodies used in ELIS
Igneous body characterization by means of seismic reflection attributes and wavelet transform
No full textIntroduction. The aim of this work is the detection and characterization of several igneous bodies observed in a series of 2D seismic sections. The studied seismic reflection survey has been acquired in the offshore Senegal and is located on the Western African margin, South-West of Dakar.
The identification, description and characterization of the igneous bodies is carried out by means of complex seismic attributes. The considered complex attributes are the Reflection Strength and its first and second derivative, the Instantaneous Frequency, the Instantaneous Phase, the Cosine of the Instantaneous Phase and the Sweetness. Moreover, in order to improve the visualization of the entire seismic dataset, the Continuous Wavelet Transform (CWT) is applied on the data. The CWT helps to better discriminate the geometrical features and the morphologies of the igneous bodies.
The analysis through the seismic attributes and the CWT allows to identify the amplitude anomalies related to the igneous bodies, to describe the different seismic facies and to comprehend the mutual relationship and the behaviour between them. Furthermore, it allows the evaluation of the geometrical properties of the intrusive bodies such as the thickness, lateral extent, depth of emplacement and it also permits to delineate the deformation structures, that affected the overburden due to the igneous intrusion.
Finally, the changing in the attribute response allows to divide each observed seismic section in three seismofacies and permits to classify the intrusive bodies on the basis of their age, shape and level of emplacement. Moreover, a comparison between the seismic stratigraphy and the real geological outcrops of the Senegal onshore has been attemped.
Seismic Reflection Data. This study is carried out interpreting eighteen 2D seismic lines extracted from a 3D data volume. In particular the entire dataset is composed by eleven in-lines and seven cross-lines. In Figure 1 is shown the map of the survey with the position of the seismic lines analysed; in Table 1 the most important acquisition and recording parameters are reported. All the sections are time migrated with zero phase conversion applied.
A line by line description of each amplitude anomaly is carried out. The seismic lines are characterized on the basis of their amplitude, phase and frequency by means of the complex seismic attributes (Taner et al., 1979; White, 1991; Satyavani et al., 2008; Barnes, 2001; Yushun, 2011; Subrahmanyam et al., 2008) Reflection Strength and derivatives, Instantaneous Phase, Instantaneous Frequency and Sweetness.
The Reflection Strength attribute permits to visualize the data taking into account the seismic reflectivity and, in particular, it highlights the strong impedance contrasts related to the lithological changes and thus allows to discriminate the limits between sequences and to localize the amplitude anomalies related to the igneous bodies.
Therefore, according to the observed amplitude response, each seismic section is divided into three different seismofacies (Figure 2). The seismofacies A is located in the upper part of the sections and is characterized by alternating reflectors with medium and high reflection strength response; the seismofacies B (below A) is constituted by a package of reflectors that have the maximum amplitude values, alternated by thin reflectors with medium amplitude values; the seismofacies C, located in the lower part of the sections, presents discontinuous reflectors with amplitude values much smaller than those of the seismofacies A and B. In Figure 2 is shown an example of the result obtained through the application of the Reflection Strength attribute for the inline1560 and the limits between the seismofacies A, B and C and the amplitude anomalies L, M and N are highlighted.
The Instantaneous Phase attribute is applied in order to emphasize the lateral continuity of strong as well as weak events, to estimate the geometrical properties of the amplitude anomalies and to highlight the discontinuities, such as faults.
The Instantaneous Frequency attribute is useful to discriminate the different range of frequency that characterized the data. In particular, the three seismofacies exhibit distinct Instantaneous Frequencies behaviours: the seismofacies A and B are characterized by medium to high frequency reflectors, while the seismofacies C shows a low frequency content. Furthermore, also the amplitude anomalies highlighted by the Reflection Strength attribute correspond to low Instantaneous Frequency anomalies.
The Sweetness attribute is calculated by the combination of Instantaneous Frequency and Reflection Strength (Hart, 2008; Riedel, 2010; Yushun, 2011) and it is useful to better distinguish the events characterized by high values of acoustic impedance. This attribute clearly highlights the limits of the three seismofacies as well as the anomalies. The seismofacies A presents dominant Sweetness values around zero and, within it, few reflectors with higher Sweetness values are observed. The seismofacies B is made up of packages of laterally continuous reflectors with medium-high Sweetness values. Below, the seismofacies C is characterized by the presence of less continuous reflections, compared with the seismofacies A and B. They exhibit quite high Sweetness values and are enclose in a background, that presents Sweetness values comprised between 0 and 1000.
Therefore, the detection of the anomalies related to the igneous bodies are performed through the application of the seismic attributes. In particular, the Reflection Strength and the Sweetness attributes permit to isolate the high amplitude value anomalies from the low reflective seismofacies C; the Instantaneous Phase allows to identify the bodies, that are masked by chaotic reflections, as sills with antiformal junctions, T- and F-shaped morphologies and saucer-shaped geometries. The Instantaneous Frequency permits to characterize the sills as bodies with a frequency range of about 25-30 Hz. Especially, the amplitude anomalies within the seismofacies C show values between 10 and 25 Hz, those within the seismofacies B are not resolved due to the chaotic facies with too high frequencies and the anomalies in the seismofacies A show values up to 40 Hz.
The Continuous Wavelet Transform (CWT). In order to improve the geometry interpretation, the Continuous Wavelet Transform (CWT) is applied (Debauchies, 1988; Mallat, 1989; Zhang et al., 2006). The CWT provides a method for displaying and analysing signals as a function of time and scale. The scale and the frequency are related to an inverse relationship of proportionality, which means that the higher the scale the lower the frequency. Therefore, the wavelet transform allows to decompose the seismic data into a time versus scale (frequency band) domain and subsequently, if needed, to reconstruct them in the scales of interest. The analysis of the reconstructed common scale volumes permits to obtain a representation of the frequency information, which is contained in a seismic section.
In particular, the CWT is defined as follow (Debauchies, 1988; Zhang et al., 2006):
It can be considered the cross-correlation between the seismic trace x(t) and the dilated and scaled versions of an user defined wavelet .The mother wavelet is the analysis wavelet function, a is the location parameter of the wavelet so that (t-a) define the shift of the wavelet along the trace and b is the scaling (dilation) parameter.
By shifting and scaling the mother wavelet, the Wavelet Transform is able to capture information of short duration (high frequency) or information of long duration (low frequency), at the same time.
Finally, the CWT can be interpreted as a bank of band pass filters process, but it is more flexible than other time-frequency transform such as the Short Time Fourier Transform (STFT) and it is particularly useful to locate and identify signals with exotic spectral characteristics (Sadowsky, 1996).
As well as for the seismic attributes, a line by line CWT analysis is carried out.
The CWT is tested using three different mother wavelets: the Haar wavelet, the order 2 Daubechies wavelet (db2) and the Morlet wavelet (morl).
Although the best result was expected by the application of the Morlet wavelet, that is the commonly used wavelet if the transform is aimed at improving the quality of the seismic section (Sadowsky, 1996), the db2 is adopted. As an example, the reconstruction of the inline 1560 through the sum of the coefficients of the chosen db2 scales is shown in Figure 3.
To sum-up, this analysis shows that the anomalies related to the igneous bodies can be approximated in a frequency ranges from 20 up to 30 Hz. This is in agreement with the Instantaneous Frequency response. Furthermore, the application of the CWT is useful to discriminate the igneous bodies within the seismofacies B, that were masked due to the presence of a chaotic facies.
Conclusion. The Senegal Basin is characterized by the presence of discordant low frequency high amplitude reflection anomalies, that are interpreted as Miocene intrusive bodies. This interpretation is supported by the data obtained from the on-land survey of the Senegal area. The main result of this survey is the identification of magmatic activity ranges from Oligocene to Quaternary.
From the line by line analysis of the eighteen 2D seismic lines results that the detected nineteen sills can be classified on the basis of their age, levels of emplacement and geometries. In particular, most of the sills develop within the seismofacies C at the first level of emplacement (TWT >3.5 s). These anomalies show a flat inner saucer geometry, often bounded by an inclined sheet that cross-cuts upwards the seismofacies C, and deform the overburden reflectors in a gently symmetrical antiformal fold.
The amplitude anomalies which develop in the second level of emplacement (3.5s < TWT < 2.7s) show a concave-upwards saucer-shaped morphology and are characterized by the formation of two inclined sheets, often one steeper than the other. Moreover, some of these bodies show T- and F-shaped or antiformal morphology. At the third level (TWT <2.7s), only two sills develop within the seismofacies A, cross-cut the seismo-stratigraphic reflectors, obliterate the underlying seismofacies B and deform the overlying reflectors in a domal structure.
Furthermore, by applying the seismic attributes, it is possible to better distinguish the sills on the basis of the strong Reflection Strength and Sweetness response, which allow to isolate the seismic anomalies from the low amplitude background. Also, the Instantaneous Phase allows to distinguish, particularly within the seismofacies B, the seismic bodies characterized by a composite shape and masked in a chaotic facies. The Instantaneous Frequency is useful to differentiate the igneous bodies on the basis of the frequency values, that result to be comprised between 20 and 30 Hz.
According to the seismic attributes, the results obtained by the application of the CWT permit to classify the anomalies as bodies with a frequency range about 25-30 Hz. Moreover, this tool permits to characterize the bodies on the basis of their geometrical features and is fundamental to compute thickness, lateral extent, depth of emplacement, diameter-to-depth ratio and the related-fold amplitude of the sills. Furthermore, from the obtained measurements it is possible to understand the relations between the thickness and the depth of emplacement, to compare the thickness and the related-fold amplitude and to compute the relationship between these parameters.
This work can supply new inputs that can be used to improve the knowledge of the stratigraphy, the geological setting and the evolution of the investigated area. The achieved characterization of the igneous bodies can be of crucial importance for the hydrocarbon exploration since the presence of igneous intrusions in a petroleum system could cause important effects on the maturation of the source rocks, on the creation of structural and stratigraphic trapping structures and, finally, could affect the oil migration pathway
Sensory, spectrometric (PTR–ToF–MS) and chemometric analyses to distinguish extra virgin from virgin olive oils
No full textOlive oil samples were obtained from six cultivars grown in different environments, and graded by chemical analyses as extra virgin (EVOOs). These were evaluated for flavors and off-flavors, and relative VOCs spectrum as determined by PTR–ToF–MS. A hierarchical clustering of Panel test data separated olive oil in three groups, one including the samples with perceived off-flavor (VOOs), regardless of cultivar and environment. The Pearson’s correlation coefficients between the mass data from PTR–ToF–MS and the sensory characteristics perceived by the Panel test were determined. A mass-to-sensory attributes correlation index was calculated. A colorcoded card was built up based on the intensities (ncps) of five selected protonated mass data that was able to distinguish EVOOs from VOOs olive oil samples
Nashi or Williams pear fruits? Use of volatile organic compounds, physicochemical parameters, and sensory evaluation to understand the consumer’s preference
No full textRipen “ready-to-eat” fruits of “Williams” and of two Nashi cultivars (“Hosui” and “Ya Li”), present contemporarily on the stores, were evaluated by physicochemical parameters (shape, skin color, firmness, total soluble solids, titratable acidity), volatile organic compounds (VOCs) emission, measured with a proton transfer reaction-time of flight-mass spectrometer (PTR–ToF–MS), either on whole and cube fruits, and sensory evaluation (panel test and consumer’s liking). The data were analyzed by ANOVA, LSD test, hierarchical clustering, PLS-DA, and CCOA. The highest differences for the physicochemical parameters were observed between Williams and Nashi, as Williams differentiated for sugar content and Hosui for firmness. By VOCs spectral analyses, it was observed that whole and cube “Williams” fruits had the highest number and amount of compounds, followed by “Ya Li;” “Hosui” was characterized by a few signals with low intensities. Fruits of each cultivar showed specific VOCs that could be used as markers for discrimination purposes. In “Williams” pears, the presence and amount of defined masses resulted linked to fruitiness and aroma perceived by the consumer. The higher sugar content and the typical pear aroma perceived by the panelists, emitted by “Williams,” could have influenced the consumer’s liking. The tasters appreciated “Hosui” for firmness, and “Ya Li” for visual, even if they resulted lower in sugar and flavor intensity. In the opinion of the respondents to the consumer test, “Williams” resulted the most appreciated both for the average scores of the acceptability and as percentage of responses at a level >5 of a nine-point hedonic scale
Coaching early career teachers in urban elementary schools: A mixed method study
No full textCoaching for urban early career teachers (ECTs) offers promise and aligns with features of effective professional development to support the implementation of evidence-based practices. However, the functional components and key elements of coaching and coach supervision are not well specified in the literature. The goal of the current study was to examine adherence and feasibility of a coaching intervention designed to provide urban ECTs with concentrated support in classroom management and engaging learners—two instructional domains that are robust predictors of attrition (Ingersoll and Strong in Rev Educ Res 81:201–233, 2011). Coaches (n = 6) worked with ECTs (n = 15) in three urban, high-poverty elementary schools during the 2-year intervention. A mixed-method design was employed, such that qualitative data (i.e., semi-structured interviews) and quantitative data (i.e., adherence measures) were collected concurrently, remained independent during analyses, and were integrated during interpretation (Creswell and Clark in Designing and conducting mixed methods research. Sage, Thousand Oaks, 2007). Findings revealed that ECTs generally received the intended frequency and duration of coaching but with fewer opportunities for post-conferences. Coach supervision, on average, was delivered with intended frequency, with variability across coaches. Thematic analyses highlighted coach provision of emotional and instrumental support, emphasized consistent coaching as critical, and that time was a significant barrier to ECT participation in coaching. Supervision promoted social support among coaches and provided opportunities to adapt the model to ECT needs.Peer reviewe
Communautés et écriture en ligne. Histoire, devenir, un dialogue
No full textIn this interview, Elisa Bricco talks to writer Benoît Vincent about
the transformations that have taken place over the last twenty years
as a result of the technological turn in literary production. We look
at the repercussions of technology’s hold over literary production, and
in particular at the development of the notion of author in the context
of collective writing. The example of the General Instin project will
be used to highlight some of the issues raised by digital technology in
relation to the production of literary texts.Dans cet entretien, Elisa Bricco discute avec l’écrivain Benoît Vincent
sur les transformations qui sont survenues dans les vingt dernières
années à cause du tournant technologique de la production littéraire. On
s’interroge sur les répercussions de l’emprise de la technologie sur le
faire littéraire et notamment sur le développement de la notion d’auteur
dans le contexte de l’écriture collective. L’exemple du projet Général
Instin servira pour mettre en lumières quelques enjeux du numérique
par rapport à la production de textes littéraires
Communautés et écriture en ligne. Histoire, devenir, un dialogue
No full textIn this interview, Elisa Bricco talks to writer Benoît Vincent about the transformations that have taken place over the last twenty years as a result of the technological turn in literary production. We look at the repercussions of technology’s hold over literary production, and in particular at the development of the notion of author in the context of collective writing. The example of the Général Instin project will be used to highlight some of the issues raised by digital technology in relation to the production of literary texts.Dans cet entretien, Elisa Bricco discute avec l’écrivain Benoît Vincent sur les transformations qui sont survenues dans les vingt dernières années à cause du tournant technologique de la production littéraire. On s’interroge sur les répercussions de l’emprise de la technologie sur le faire littéraire et notamment sur le développement de la notion d’auteur dans le contexte de l’écriture collective. L’exemple du projet Général Instin servira pour mettre en lumières quelques enjeux du numérique par rapport à la production de textes littéraires
Tetragonia tetragonioides (Pallas) Kuntz. as promising salt-tolerant crop in a saline agricultural context
No full textThe lack of natural resources, especially good-quality cropland and renewable water resources is threatening food production potential in marginal agricultural ecosystems, which are already negatively affected by climate change. Since the world's major crops are proving inadequate to supply the calories and nutrients for people in these areas, new crops are sought that can withstand harsh ecological environmental conditions. In the current trial, we assessed the growth and productivity of Tetragonia tetragonioides (Pallas) Kuntz. in a floating hydroponic system supplied with different seawater proportions (i.e. 15% and 30% seawater, EC = 9.8 and 18.0 dS m−1). Moreover, the effects of different salinity levels on mineral elements accumulation, production of osmotic solutes and secondary metabolites were determined, along with the salt removal capacity of the crop. The results indicated that plant growth was not affected by either of the seawater treatments used in this study. The increased leaf succulence and the reduction of both leaf area and specific leaf area with increasing salinity might represent an essential feature of this salt-tolerant species associated to the plants need of limiting transpiration. Low seawater treated plants showed a significantly higher biomass yield per liter of (sea)water used (117%) than the control. Under these conditions plants accumulated the highest amount of Mg (+31% and 48% in medium and high seawater treated plants compared with the control) and Cu (+14% and 30%, respectively) along with increasing proline and decreasing nitrate concentrations. By contrast, we found that seawater supply resulted in a Na-enriched leaf biomass that may represent an issue for human health. We concluded that Tetragonia tetragonioides can be grown in saline agriculture up to a salinity level characterized by an EC of 18 dS m-1 but further investigation is required to address Na accumulation in leaves
Comment on Bandelli and Porcelli/1 - Against Moral Panic, in Defence of Data
No full textElisa Giomi’s commentary is an answer to Bandelli and Porcelli’s essay “Femicide in Italy. ‘Femminicidio,’ Moral Panic and Progressivist Discourse” [2016]. Although Giomi assumes that Bandelli and Porcelli effectively illustrate the instrumentalization of lethal violence against women in Italian political discourse, yet she criticizes their reading of the “femminicidio narrative” as a phenomenon of moral panic that locates the threat in the typical Italian heterosexual family/couple: all the available empirical findings confirm that these are precisely the contexts where lethal aggressions against women most frequently occur. The author also disagrees with the authors’ conclusion that the femminicidio narrative authorized “the application of a gender paradigm to the official reading of domestic/partner violence” in 2012/13 Italian public discourse. Finally, she contends that in their essay the “feminist discourse” is represented in a stereotypical way, one that is instrumental in depicting it as a hegemonic discourse
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