592 research outputs found

    LA DEFINIZIONE ARISTOTELICA DI MOVIMENTO E LA CRITICA AI PREDECESSORI. ARISTOT. PHYS. III 2, 201B16-202A3

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    In Physics, III 2, 201b16-202a3, Aristotle offers a negative argument in favour of his definition of change. Having previously stated what change is, he seeks confirmation for his theory in the dialectical examination of his predecessors’ conception of movement. Most commentators have neglected the passage, in part, because it is obscure and, in part, because, being postponed after the substantive discussion, it seems to be irrelevant to reconstruct Aristotle’s positive treatment of kinesis. But, criticizing his predecessors, evidently Aristotle is also providing some helpful criteria to correctly interpret his rather unclear and much discussed definition of motion. Therefore, the scope of this article is twofold. On a one hand, it attempts to use the negative argument in support of the relational interpretation of Aristotle’s definition of movement given by Monica Ugaglia. On the other hand, in the light of the relational interpretation of Aristotle’s definition of change, it seeks to solve some textual and exegetical problem of the negative argument itself and to identify its main targe

    Early Arrival of New World Species Enriching the Biological Assemblage of the Santi Quattro Coronati Complex (Rome, Italy)

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    This paper reports the archaeobotanical and archaeozoological data from a disposal pit, whose use started after the partial closure of a staircase, and from a mortar surface within a former porch in the Santi Quattro Coronati complex in Rome, Italy. The two contexts were in use in the Early Modern Age, when the complex served as a cardinal seat. The element that distinguishes the Santi Quattro Coronati from other contemporaneous contexts is the presence of New World species, until now only hypothesized based on a letter sent by the first resident bishop in Santo Domingo to Lorenzo Pucci, then cardinal with the titulus of the Santi Quattro Coronati. Pumpkin seeds (Cucurbita pepo and C. maxima/moschata) were found in the pit, while a pelvis of guinea pig (Cavia porcellus) was found in a former porch. Numerous archaeobotanical remains preserved by mummification, identified mostly as food, and many archaeozoological specimens were found in the pit. Based on the data, it is hypothesized that the pit was used mainly as a deposit for table waste. The results as a whole help towards the investigation of the eating customs and daily habits of a Renaissance high-status clerical community

    Genetic aspects of Paget’s disease of bone

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    Paget’s disease of bone (PDB) is a metabolic bone disease characterized by excessive bone resorption and formation due to increased osteoclasts activity. PDB mostly runs asymptomatically, although increased bone turnover can be present and in approximately 30% of patients bone abnormalities, such as bone pain and deformities, pathological fractures and deafness may occur. The existence of familial aggregation of PDB has been reported in numerous papers, describing the occurrence of disease in successive generations. It has been clearly established that PDB is genetically heterogeneous with several loci able to confer an increased susceptibility to develop this bone metabolic disorder. In particular, the PDB3 locus in chromosome 5q35-qter hosts the sequestosome1/ p62 (SQSTM1/p62) gene whose mutations account for most of the sporadic and familial forms of PDB reported in literature. SQSTM1/p62 gene encodes the SQSTM1/p62 protein, component of the NF-kB signaling pathway and mediating intracellular signaling from IL-1/TNF toward NF-kB, crucial for osteoclast differentiation and activity. A functional study suggests that the S Q S T M 1 mutation may predispose to PDB affecting the interaction between SQSTM1/p62 protein and a hitherto unidentified protein(s) modulating the bone turnover, but the underlying molecular mechanism need to be elucidated. However, independently from the knowledge of the functional aspects of S Q S T M 1 / p 6 2 mutation, the opportunity to perform germline mutational analysis in PDB patients may be helpful in detecting new genetic carriers in potentially familial forms of PDB and in studying the co-segregation of such DNA variants with the PDB phenotype. All together these studies could open new possibilities in the prevention and therapy of PDB and of other metabolic bone disorder

    Multidisciplinary Approach to Structural/Energy Diagnosis of Historical Buildings: A Case Study

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    Abstract A synergic approach for the investigations of the historical building performances - with reference to both the structural behavior and the energy performances for the space heating and cooling - is presented. The historical masonry building "Palazzo Bosco Lucarelli", located in Benevento, has been chosen as case study. The structural and energy analyses are carried out in parallel, especially during the identification of the building characteristics through tests and surveys in-situ. For the structural analysis - beyond examinations on materials - some dynamic tests have been used for better assessing a numerical Finite Element model necessary for the verification of the structure safety. Moreover, being necessary a structural refurbishment, also an energy retrofit could be realized. A rigorous evaluation procedure - aimed to guarantee the necessary reliability of numerical predictions - is performed in order to verify the technical and economical convenience of various energy retrofit solutions

    N-acetylcysteine serves as substrate of 3-mercaptopyruvate sulfurtransferase and stimulates sulfide metabolism in colon cancer cells

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    Hydrogen sulfide (H2S) is an endogenously produced signaling molecule. The enzymes 3-mercaptopyruvate sulfurtransferase (MST), partly localized in mitochondria, and the inner mitochondrial membrane-associated sulfide:quinone oxidoreductase (SQR), besides being respectively involved in the synthesis and catabolism of H2S, generate sulfane sulfur species such as persulfides and polysulfides, currently recognized as mediating some of the H2S biological effects. Reprogramming of H2S metabolism was reported to support cellular proliferation and energy metabolism in cancer cells. As oxidative stress is a cancer hallmark and N-acetylcysteine (NAC) was recently suggested to act as an antioxidant by increasing intracellular levels of sulfane sulfur species, here we evaluated the effect of prolonged exposure to NAC on the H2S metabolism of SW480 colon cancer cells. Cells exposed to NAC for 24 h displayed increased expression and activity of MST and SQR. Furthermore, NAC was shown to: (i) persist at detectable levels inside the cells exposed to the drug for up to 24 h and (ii) sustain H2S synthesis by human MST more effectively than cysteine, as shown working on the isolated recombinant enzyme. We conclude that prolonged exposure of colon cancer cells to NAC stimulates H2S metabolism and that NAC can serve as a substrate for human MST

    Improving the performances of supported NiCo catalyst for reforming of methane powered by magnetic induction

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    NiCo supported magnetic nanoparticles can catalyze the steam reforming of methane and at the same time provide the heat necessary to run the process by dissipating an external radio frequency electromagnetic field. Magnetic samples with different Ni:Co molar ratio and total metal loading on the support have been synthesized using a traditional impregnation procedure and characterized in terms of morphological and structural properties. The ability of the materials to provide process heat was assessed by temperature measurements. Methane conversion value and syngas composition have been measured for different applied field amplitude. The sample with a composition Ni50Co50_30 wt% was found to be the most performing in terms of conversion obtained with the same applied magnetic field. The developed magnetic catalysts contribute to the transition to distributed hydrogen production and help to tackle some of the challenges related to the intensification of production processes by electrification

    Current Trends in Gelatin-Based Drug Delivery Systems

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    Gelatin is a highly versatile natural polymer, which is widely used in healthcare-related sectors due to its advantageous properties, such as biocompatibility, biodegradability, low-cost, and the availability of exposed chemical groups. In the biomedical field, gelatin is used also as a biomaterial for the development of drug delivery systems (DDSs) due to its applicability to several synthesis techniques. In this review, after a brief overview of its chemical and physical properties, the focus is placed on the commonly used techniques for the development of gelatin-based micro- or nano-sized DDSs. We highlight the potential of gelatin as a carrier of many types of bioactive compounds and its ability to tune and control select drugs' release kinetics. The desolvation, nanoprecipitation, coacervation, emulsion, electrospray, and spray drying techniques are described from a methodological and mechanistic point of view, with a careful analysis of the effects of the main variable parameters on the DDSs' properties. Lastly, the outcomes of preclinical and clinical studies involving gelatin-based DDSs are thoroughly discussed

    Energy Performance of Cool-colors and Roofing Coatings in Reducing the Free Solar Gains during the Heating Season: Results of an In-Field Investigation☆

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    Abstract Today, it is not well-known the impact of cool roofs during heating season in balanced climates. Proposed study tries to quantify the increase of energy demands of buildings characterized by high-reflective and high-emissive coatings of roof, by means of experiments and numerical simulations. Three coatings are investigated with different solar absorptance and thermal emittance. The experiments have been carried out at the living lab of the University of Sannio, a full-scale test-room, provided with a large flexibility in terms of variability of the thermal envelope and air-conditioning system. Moreover, numerical evaluations of heating and annual energy consumptions are presented

    energy refurbishment of a university building in cold italian backcountry part 1 audit and calibration of the numerical model

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    Abstract The study provides a methodological approach for designing energy refurbishment measures of buildings, enabling to understand the uncertainty of using numerical modelling and the real impacts due of adopting some energy efficiency technologies. The case study is a University building of the centre of Italy, and the reference scenario has been supported by various in-situ surveys, investigations and evaluations of the indoor comfort. Collected data, together with a comparison with energy bills, has allowed a proper calibration of a numerical model simulated by means EnergyPlus. All this phase is described in this paper, while a second part will discuss the energy retrofit and the building energy optimization
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