1,723 research outputs found

    Handbook for in-service teacher training

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    This Handbook for in-service teacher training is one of the outcomes of the EHISTO (European history crossroads as pathways to intercultural and media education) project. It is intended for use by teacher instructors in both the University context and local institutions during in-service teacher training. The handbook is made up of two parts: - Part 1 introduces the reader to the main project outcomes both in terms of methodological approach to the development of intercultural and media-critical competencies among pupils, and in terms of didactical strategies and materials to be used in Secondary School History classrooms. - Part 2 proposes the design of a course devoted to Secondary School in-service teachers, with the aim of providing participants with both a framework, as well as suggestions for practical use of the learning material in the EHISTO Learning Objects (LOs).This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein

    Salt-gradient Solar Ponds: Summary of US Department of Energy Sponsored Research

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    The solar pond research program conducted by the United States Department of Energy was discontinued after 1983. This document summarizes the results of the program, reviews the state of the art, and identifies the remaining outstanding issues. Solar ponds is a generic term but, in the context of this report, the term solar pond refers specifically to saltgradient solar pond. Several small research solar ponds have been built and successfully tested. Procedures for filling the pond, maintaining the gradient, adjusting the zone boundaries, and extracting heat were developed. Theories and models were developed and verified. The major remaining unknowns or issues involve the physical behavior of large ponds; i.e., wind mixing of the surface, lateral range or reach of horizontally injected fluids, ground thermal losses, and gradient zone boundary erosion caused by pumping fluid for heat extraction. These issues cannot be scaled and must be studied in a large outdoor solar pond

    Role of the ancillary ligands on the stabilization of the imino-oxo tautomer of 1-methylcytosine in PtII complexes

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    The mixed nucleobases complexes cis-[L2Pt{1-MeTy(-H)}(1-MeCy,N3)]NO3 (L = PPh3, 1a; PMePh2, 1b), containing the N(3)-deprotonated 1-methylthymine (1-MeTy(-H)) and the neutral 1-methylcytosine (1-MeCy) have been prepared and characterised. The compounds were obtained by reacting the hydroxo complexes cis-[L2Pt(ÎŒ-OH)]2(NO3)2 with 1-methylthymine (1-MeTy), followed by the addition of 1 equivalent of 1-MeCy. In solution of DMSO, DMF or chlorinated solvents, 1a converts quantitatively into the isomer cis-[L2Pt{1-MeTy(-H)}(1-MeCy,N4)]NO3 (2a) containing the tautomeric form of the cytosine stabilized through the coordination at the N(4) atom, as shown by single-crystal X-ray analysis. The structural determination of 2a shows the presence in the unit cell of two crystallographic independent complexes having similar conformation, with a different orientation of the two nucleobases (head–head and head–tail) according to the presence of both isomers in solution. Complex 1b, having the less hindered PMePh2 ligands, in DMSO solution, contains the tautomeric forms of the cytosine in equilibrium and the migration of the metal from the N(3) to N(4) site occurs only to a minor extent

    Structural Aspects of Palladium Systems Used as Catalyst Precursors in CO/olefins co- and ter-Polymerisation Reactions

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    The synthesis and characterisation of three palladium complexes, involved in the homogeneous catalysis towards the CO-olefins co-and ter-polymerisation reactions, are reported. The [Pd (dpk⋅CH3OH) (CF3CO2)2] (1), (dpk = di(2-pyridyl) ketone) and [Pd (dppp)(bipy)] [B(C6F5)4]2 (2), (bipy = 2,2’-bipyridine, dppp = 1,3-bis(diphenylphosphino)propane) compounds are examples of a neutral complex and of a dicationic mixed-ligands one, respectively. The catalytic activity of type 2 complexes was reported to be strongly dependent on the nature of the anion, and the tetra(perfluorophenyl) borate salt represents the best choice to date for the CO/aliphatic olefins copolymerisation. In both structures, the metal has a square planar coordination and the structural aspects of these complexes are discussed in comparison with their catalytic properties. The crystal structure of [Pd(bipy)(naphthoquinone)] (3), which is a putative intermediate of the catalytic cycle, is also reported

    Geocoding health data with Geographic Information Systems: a pilot study in northeast Italy for developing a standardized data-acquiring format

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    Introduction. Geographic Information Systems (GIS) have become an innovative and somewhat crucial tool for analyzing relationships between public health data and environment. This study, though focusing on a Local Health Unit of northeastern Italy, could be taken as a benchmark for developing a standardized national data-acquiring format, providing a step-by-step instructions on the manipulation of address elements specific for Italian language and traditions. Methods. Geocoding analysis was carried out on a health database comprising 268,517 records of the Local Health Unit of Rovigo in the Veneto region, covering a period of 10 years, starting from 2001 up to 2010. The Map Service provided by the Environmental Research System Institute (ESRI, Redlands, CA), and ArcMap 10.0 by ESRI\uae were, respectively, the reference data and the GIS software, employed in the geocoding process. Results. The first attempt of geocoding produced a poor quality result, having about 40% of the addresses matched. A procedure of manual standardization was performed in order to enhance the quality of the results, consequently a set of guiding principle were expounded which should be pursued for geocoding health data. High-level geocoding detail will provide a more precise geographic representation of health related events. Conclusions. The main achievement of this study was to outline some of the difficulties encountered during the geocoding of health data and to put forward a set of guidelines, which could be useful to facilitate the process and enhance the quality of the results. Public health informatics represents an emerging specialty that highlights on the application of information science and technology to public health practice and research. Therefore, this study could draw the attention of the National Health Service to the underestimated problem of geocoding accuracy in health related data for environmental risk assessment

    Structural Aspects of Palladium Systems Used as Catalyst Precursors in CO/olefins co- and ter-Polymerisation Reactions

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    The synthesis and characterisation of three palladium complexes, involved in the homogeneous catalysis towards the CO-olefins co-and ter-polymerisation reactions, are reported. The [Pd (dpk⋅CH3OH) (CF3CO2)2] (1), (dpk = di(2-pyridyl) ketone) and [Pd (dppp)(bipy)] [B(C6F5)4]2 (2), (bipy = 2,2’-bipyridine, dppp = 1,3-bis(diphenylphosphino)propane) compounds are examples of a neutral complex and of a dicationic mixed-ligands one, respectively. The catalytic activity of type 2 complexes was reported to be strongly dependent on the nature of the anion, and the tetra(perfluorophenyl) borate salt represents the best choice to date for the CO/aliphatic olefins copolymerisation. In both structures, the metal has a square planar coordination and the structural aspects of these complexes are discussed in comparison with their catalytic properties. The crystal structure of [Pd(bipy)(naphthoquinone)] (3), which is a putative intermediate of the catalytic cycle, is also reported

    Mono- and Polynuclear Complexes of the Model Nucleobase 1-Methylcytosine. Synthesis and Characterization of cis-[(PMe2Ph)2Pt{(1-MeCy(−H)}]3(NO3)3 and cis-[(PPh3)2Pt{1-MeCy(−H)}(1-MeCy)]NO3

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    The hydroxo complex cis-[L2Pt(ÎŒ-OH)]2(NO3)2 (L = PMe2Ph), in various solvents, reacts with 1-methylcytosine (1-MeCy) to give as the final product the cyclic species cis-[L2Pt{1-MeCy(−H),N 3N 4}]3(NO3)3 (1) in high or quantitative yield. X-ray analysis of 1 evidences a trinuclear species with the NH2-deprotonated nucleobases bridging symmetrically the metal centers through the N3 and N4 donors. A multinuclear NMR study of the reaction in DMSO-d6 reveals the initial formation of the dinuclear species cis-[L2Pt{1-MeCy(−H),N 3N 4}]22+ (2), which quantitatively converts into 1 following a first-order kinetic law (at 50 °C, t1/2 = 5 h). In chlorinated solvents, the deprotonation of the nucleobase affords as the major product (60−70%) the linkage isomer of 1, cis-[L2Pt{1-MeCy(−H)}]33+ (3), in which three cytosinate ligands bridge unsymmetrically three cis-L2Pt2+ units. In solution, 3 slowly converts quantitatively into the thermodynamically more stable isomer 1. No polynuclear adducts were obtained with the hydroxo complex stabilized by PPh3. cis-[(PPh3)2Pt(ÎŒ-OH)]2(NO3)2 reacts with 1-MeCy, in DMSO or CH2Cl2, to give the mononuclear species cis-[(PPh3)2Pt{1-MeCy(−H)}(1-MeCy)](NO3) (4) containing one neutral and one NH2-deprotonated 1-MeCy molecule, coordinated to the same metal center at the N3 and N4 sites, respectively. X-ray analysis and NMR studies show an intramolecular H bond between the N4 amino group and the uncoordinated N3 atom of the two nucleobases

    Robust low-rank training via approximate orthonormal constraints

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    With the growth of model and data sizes, a broad effort has been made to design pruning techniques that reduce the resource demand of deep learning pipelines, while retaining model performance. In order to reduce both inference and training costs, a prominent line of work uses low-rank matrix factorizations to represent the network weights. Although able to retain accuracy, we observe that low-rank methods tend to compromise model robustness against adversarial perturbations. By modeling robustness in terms of the condition number of the neural network, we argue that this loss of robustness is due to the exploding singular values of the low-rank weight matrices. Thus, we introduce a robust low-rank training algorithm that maintains the network's weights on the low-rank matrix manifold while simultaneously enforcing approximate orthonormal constraints. The resulting model reduces both training and inference costs while ensuring well-conditioning and thus better adversarial robustness, without compromising model accuracy. This is shown by extensive numerical evidence and by our main approximation theorem that shows the computed robust low-rank network well-approximates the ideal full model, provided a highly performing low-rank sub-network exists

    Microstructural features of human bones and funerary practices in Mount Sirai (Sardinia)

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    In the attempt to set up a useful methodology for the investigation of burned human remains in archaeological, anthropological and forensic fields, we decided to compare the most common protocols for the study of bone bioapatites (Fourier Transform Infrared spectroscopy, FT-IR, and X-ray Diffraction, XRD) to those deriving from the application of X-ray scattering techniques using synchrotron light. In this way, we expect to take advantage of the wider and more dynamic qualities of such a valuable tool in order to examine a higher number of samples in a very short time compared to the “traditional” techniques, meanwhile assessing its applicability in the archaeological field
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