879 research outputs found

    Two-component organic crystals without hydrogen bonding: structure and intermolecular interactions in bimolecular stacking

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    A survey of crystal structures including two organic compounds unable to form hydrogen bonding has been carried out using the Cambridge Structural Database. Such systems are common and numerous. Association modes mostly include stacking of flat systems, one of them usually being an aromatic hydrocarbon. \u201cAlternate-ladder\u201d (AL) and \u201cslanted column\u201d (SC) motifs occur most frequently; AL is somewhat prevalent in fluoroarene and pyromellitic dianhydride cocrystals, whereas SC occurs preferentially, but not exclusively, with quinones, nitrobenzene, TCNB and TCNQ coformers. Segregation of A and B chemical units in separate columns is very seldom observed, while A efB is the energetically dominating pair in a vast majority of the cases. A stable network of stacked A efB units seems to be a strict requirement for observing cocrystallization, even more than an overall higher stability of the cocrystal with respect to its coformers. This highlights the central role of kinetic factors in determining the drive to stacking heterorecognition. Energy dissection using the PIXEL scheme shows that dispersion energies play a dominant but not exclusive role. The interaction between flat organic systems is found to be a viable synthetic approach for cocrystallization, on the same footing as the more popular O\u2013H efO, O\u2013H efN and N\u2013H efO hydrogen bonding. Some practical suggestions for the choice of the best coformers are provided

    Sulle orme del consumatore affinity analysis e knowledge visualization per il processo decisionale

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    L\u2019articolo analizza i reali comportamenti di acquisto dell\u2019acquirente all\u2019interno del punto vendita e individua i pattern latenti pi\uf9 significativi attraverso un\u2019analisi di affinit\ue0 di 128.364 scontrini estratti da un dataset di 715.662 transazioni effettuate in un anno. Lo studio individua le strutture associative pi\uf9 ricorrenti relativamente alla singola merceologia. Attraverso la tecnica della Market Basket Analysis \ue8 stato possibile individuare le categorie merceologiche che creano \u201cpoli d\u2019attrazione\u201d sul punto vendita stimolando acquisti di altre categorie. In particolar modo, applicando le regole associative sul punto vendita \ue8 stato possibile identificare le \u201caree calde\u201d e le \u201caree fredde\u201d. L\u2019articolo evidenzia quindi alcune riflessioni sulle strategie che possono adottare gli store manager

    SUP&R DSS: A sustainability-based decision support system for road pavements

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    Road pavement community members are increasingly becoming aware of the need to incorporating the principles of sustainable development into the sector. Policies are also going in this direction and as a consequence in the recent years researchers and practitioners are coming up with new materials, technologies and practices designed to reduce the negative impacts of their activities in the surroundings. Within this framework the road pavements sector is witnessing a paradigm shift towards the development of pavement technologies incorporating high-content of recycled materials, as well as best practices to decrease the overall carbon footprint. These are all promising solutions that to the most can sound as sustainable practices. However the whole road pavement community is still investigating methodologies and tools to define what actually sustainable means and thereby performing a sustainable decision-making. It is within this context that the need of a sustainability-based decision support system (DSS) that could help road pavement engineers at the design stage was identified and is here presented. The Sustainable Pavements & Railways DSS (SUP&R DSS) relies on a multi-criteria decision analysis (MCDA) method to rank the sustainability of alternatives. It applies life cycle-based approaches to quantify the values of a set of indicators purposely and methodologically selected to capture the cause- effect link between the general concepts of the three wellbeing dimensions of sustainability, i.e., environmental, economic and social, and the infrastructure construction and maintenance practice. Furthermore, the system allows selecting different weighting for the indicators but offers also a default set of values derived from a survey conducted with over 50 stakeholders in Europe and beyond. Together with the development, structure and features of the SUP&R DSS, this paper present its applicability by means of a case study aiming at identifying the most sustainable asphalt mixture for wearing courses. Several promising options for flexible road pavements were selected, ranging from low to hot temperature asphalt. The results show that a foamed warm mix asphalt mixture with a reclaimed asphalt pavement content of 50% is the most sustainable among the competing alternatives. Furthermore, a sensitivity analysis conducted to investigate the influence of the indicators weights, the parameters of the MCDA method and the long-term performance of the alternative asphalt mixtures on the stability of the ranking showed that its first position in the ranking remained unaffected

    Smart Analogue Sampler for the Optical Module of a Cherenkov Neutrino Detector

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    A transient waveform sampler/recorder IC has been developed and realized in AMS C35B4 technology. This chip has been designed to fit the needs of a proposal for a front-end architecture for the readout of the anode signal of the photomultipliers in an underwater neutrino telescope. The design is based around a 3 channels x 32 cells switched capacitor array unit sampling its voltage inputs at 200MHz external clock rate and transferring the stored analogue voltage samples to its single analogue output at 1/10th of the sampling rate. This unit is replicated inside the ASIC providing 4 independent analogue sampling queues for signal transients up to 32 x 5 ns and a fifth unit storing transients up to 128 x 5 ns. A micro-pipelined unit, based on Muller C-gates, controls the 5 independent samplers. This paper briefly summarizes the complete front-end architecture and discusses in more detail the internal structure of the ASIC and its first functional tests

    Spatial extent of recent vertical tectonic motions misured in NE Sicily coastal area. Insights from marine geology and coastal geomorphology studies.

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    Vertical position of sea-level, pointed out by related deposits and morphologies, provide useful markers to estimate tectonic uplift rates. For the Holocene very high uplift rates are misured in the northeast Sicily coast (Antonioli et al., 2009). This study compare vertical tectonic movements and marine geology data in the coastal sector between Capo d\u2019Orlando and Brolo (NE Sicily); tectonic lineaments show different trends both onland (Nigro & Sulli, 1995) and offshore (Nicolich et al.,1982) and also the morphological response follow closely this difference. The geomorphologic survey provided data on Holocene uplift rates. We studied an archaeological ancient quarry of grinding wheels for oil that has been found in the Capo d\u2019Orlando inshore (Scicchitano et al., 2011). They present semi submerged circular holes in Stilo-Capo d\u2019Orlando deposits (Carbone et al., 1998). The tectonic uplift was evaluated as the difference between the observed local paleo-sea level position and the predicted sea-level curve for the same locality (Lambeck et al., 2011). The resulting uplift rates is 0.36 mm/yr (Scicchitano et al., 2011). In this area we studied also the Brolo stack. It is a metamorphic rocks emerging at 450 m from the coastline. The study led to discovery a fossils-bearing conglomerate in protected trays at 3.5 m a.s.l.. Radiocarbon analysis on a gastropod, gave us an age of 4965 years +-70 cal BP. If we compare this data with the predicted local sea level curves (Lambeck et al., 2011), we obtain an uplift rate about 1.5 mm/yr (Lo Presti et al., 2010), which is higher than that calculated in the study of archaeological rest. A detailed study of Brolo sector show us different morphological coastline position of Brolo plain. A picture of the year 1847 shows the coastline about 200 m landward. In Brolo coastal plain we have also found a Spondylus at -6 m b.s.l. We wait for the radiocarbon dating which allows us to have a new uplift rate data. The analysis of marine geology data (Multibeam) evidenced structures connected to different faults systems, such as the submarine canyons that are the continuation of river beds. Multibeam data evidenced also tilted NE-ward submerged surfaces, indicating existing structural movements, interesting only restricted areas. So, very different uplift rates in the Holocene in very close areas distant only about 10 kilometers: both 0.36 mm/yr (Scicchitano et al. 2011) and 1.5 mm/yr (Lo Presti et al. 2010), and morphobathymetric data (tilted surfaces), evidence the important role of active tectonic lineaments. Seismic reflection profiles support this assumption, showing the metamorphic basement strongly dissected by high-angle faults, which at place determines the occurrence of emergent rock bodies (e.g. the Brolo stack). All this suggesting the occurrence of \u201crestricted regions\u201d in the coastal-marine sector with different geological behavior as response to prominent tectonic releasing bands, determining their horizontal and vertical movements

    Rosemary extract (Rosmarinus officinalis L.) supplementation into the diet of Nero Siciliano pigs: effects on lipid oxidation

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    During the growing-fattening period (93 days; ILW 33.5±6 kg to FLW 67±3 kg), 30 Nero Siciliano pigs were fed on a basal diet supplemented with (ROX group) or not (CTR group) a rosemary extract (1g?kg-1). At 1, 3 and 5 days after slaughtering, the oxidative stability of the Longissimus dorsi muscle was determined by using TBArs test. Moreover, on the individual samples of the muscle the lipid content, the fatty acid and the sterol composition were determined; the acidic composition of the lard, removed from backfat, was also studied. Data were subjected to ANOVA. The fat content of the muscle was unaffected by the dietary treatment as well as the oxidative stability whereas, significant differences (P²0.01) were observed for the polyunsaturated fatty acid content which showed the highest values in the meat as well as in the lard of the ROX group; PUFA/SFA ratio was also significantly highest in the muscle (P=0.004) and in the lard (P=0.017) of the ROX group, testifying a possible antioxidative activity of the rosemary extract. The sterol fraction (cholesterol, cholestanol, stigmasterol, beta-sitosterol and delta 5-avenasterol) of the Longissimus dorsi muscle was unaffected by the rosemary supplementation; a significant difference was observed only for the campesterol (CTR group=1.08, ROX group=0.90; P = 0.021)

    Network loss tomography using striped unicast probes

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    Supplementation of Rosemary extract in the diet of Nero Siciliano pigs: evaluation of the antioxidant properties on meat quality.

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    In the present study, the effect of Rosmarinus officinalis L. dietary supplementation on meat quality and oxidative stability of Nero Siciliano pigs was examined. During the growing–fattening period, 32 Nero Siciliano pigs were allotted into two treatment groups consisting of 8 replicates with 2 pigs per pen. For 90 days, the animals received a basal diet: one group (CTR) was not dietary supplemented, whereas the other group received (1 g/kg) rosemary extract (ROX). Supplementation with rosemary extract significantly improved the polyunsaturated fatty acid content of the meat, which showed higher values in the meat of the ROX group compared with the CTR group (P0.05). Color measurement performed in the present study on meat samples from the two dietary treatments showed that redness decreased (P=0.046) and hue values increased (P=0.036), indicating that a deterioration of the initial color occurred and that the rosemary extract was ineffective in preventing color deterioration. Nevertheless, the lightness, yellowness and chroma color descriptors showed similar values in relation to dietary treatment (P>0.05). Considering the nutritional value of meat as an important contributor to the overall quality, the results obtained in this study support the possibility of the dietary supplementation with R. officinalis L. extract in pigs as a functional additive in livestock feeding

    Alkaline phosphatase survey in pecorino siciliano PDO cheese

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    The determination of alkaline phosphatase (ALP) in cheeses has become an official method for controlling cheeses with a protected designation of origin (PDO), all of which use raw milk. PDO cheeses, characterized by high craftsmanship, usually have an uneven quality. However, for these cheeses, it is necessary to establish ALP values so that they can be defined as a raw milk product. In this study, a dataset with Pecorino Siciliano PDO samples was analyzed to determine ALP both at the core and under the rind. The results showed that there was no significant difference between the different zones in Pecorino cheese. A second dataset of 100 pecorino cheese samples determined that ALP was only at the core of the cheese. Moreover, there was a statistically significant difference between the ALP values of cheeses produced with raw milk and those produced with pasteurized milk. Furthermore, according to the temperatures, a wide variability of ALP values was observed in the Pecorino Siciliano PDO samples from the core of the cheeses. This was a result of several under scotta whey cooking methodologies adopted by cheesemakers, which do not permit a clear range. Therefore, further investigation is desirable

    Comparing marine geology and coastal geomorphology vertical tectonic data, a case study between Acquedolci and Patti (Messina).

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    The study of new data on vertical movements show a complex geologic response in a restricted sector of coastal area between Acquedolci and Patti (north-eastern Sicily). Different surveys allowed to the recognition of morphological, biological and archaeological markers of paleo-sea level. The analysis of these markers and the absolute datings performed, allowed to reconstruct the history of vertical deformation of this sector but only the comparison among coastal geomorphological data and marine geological data of platform-scarp continental system associates, allowed to find the necessary keys words to explain the geologic complexity of this sector
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