341 research outputs found
Computation and Palaeography: Potentials and Limits
This manifesto documents the program and outcomes of Dagstuhl Seminar 12382 ‘Perspectives Workshop: Computation and Palaeography: Potentials and Limits’. The workshop focused on the interaction of palaeography, the study of ancient and me- dieval documents, with computerised tools, particularly those developed for analysis of digital images and text mining. The goal of this marriage of disciplines is to provide e cient solutions to time and labor consuming palaeographic tasks. It furthermore attempts to provide scholars with quantitative evidence to palaeographical arguments, consequently facilitating a better understanding of our cultural heritage through the unique perspective of ancient and medieval documents. The workshop provided a vital opportunity for palaeographers to interact and discuss the potential of digital methods with computer scientists specialising in machine vision and statistical data analysis. This was essential not only in suggesting new directions and ideas for improving palaeographic research, but also in identifying questions which scholars working individually, in their respective elds, would not have asked without directly communicating with colleagues from outside their research community
Synthesis, structural characterization, antimicrobial and cytotoxic effects of aziridine, 2-aminoethylaziridine and azirine complexes of copper(II) and palladium(II).
The synthesis, spectroscopic and X-ray structural characterization of copper(II) and palladium(II) complexes with aziridine ligands as 2-dimethylaziridine HNCH2CMe2 (a), the bidentate N-(2-aminoethyl)aziridines C2H4NC2H4NH2 (b) or CH2CMe2NCH2CMe2NH2 (c) as well as the unsaturated azirine NCH2CPh (d) are reported. Cleavage of the cyclometallated Pd(II) dimer [μ-Cl(C6H4CHMeNMe2-C,N)Pd]2 with ligand a yielded compound [Cl(NHCH2CMe2)(C6H4CHMe2NMe2-C,N)Pd] (1a). The reaction of the aziridine complex trans-[Cl2Pd(HNC2H4)2] with an excess of aziridine in the presence of AgOTf gave the ionic chelate complex trans-[(C2H4NC2H4NH2-N,N′)2Pd](OTf)2 (2b) which contains the new ligand b formed by an unexpected insertion and ring opening reaction of two aziridines (“aziridine dimerization”). CuCl2 reacted in pure HNC2H4 or HNCH2CMe2 (b) again by “dimerization” to give the tris-chelated ionic complex [Cu(C2H4NC2H4NH2-N,N′)3]Cl2 (3b) or the bis-chelated complex [CuCl(C2H2Me2NC2H2Me2NH2-N,N′)2]Cl (4c). By addition of 2H-3-phenylazirine (d) to PdCl2, trans-[Cl2Pd(NCH2CPh)2] (5d) was formed. All new compounds were characterized by NMR, IR and mass spectra and also by X-ray structure analyses (except 3b). Additionally the cytotoxic effects of these complexes were examined on HL-60 and NALM-6 human leukemia cells and melanoma WM-115 cells. The antimicrobial activity was also determined. The growth of Gram-positive bacterial strains (S. aureus, S. epidermidis, E. faecalis) was inhibited by almost all tested complexes at the concentrations of 37.5–300.0 μg mL−1. However, MIC values of complexes obtained for Gram-negative E. coli and P. aeruginosa, as well as for C. albicans yeast, mostly exceeded 300 μg mL−1. The highest antibacterial activity was achieved by complexes 1a and 2b. Complex 2b also inhibited the growth of Gram-negative bacteria.
Graphical abstract: Synthesis, structural characterization, antimicrobial and cytotoxic effects of aziridine, 2-aminoethylaziridine and azirine complexes of copper(ii) and palladium(ii
The radicalization of democracy: conflict, social movements and terrorism
The idea of democracy is being championed across the world, with some fifty new countries embracing this type of political system between 1974 and 2011 (Freedom House, 2016). Simultaneously, however, dissatisfaction has grown due to the perceived incapacity of democracy to deal with collective problems, hence the necessity to reconfigure it and redraw some of its principles. This paper links the analysis of the recent evolution of democratic systems with the trajectory of socio-political conflicts and the changing features of contemporary terrorism. It examines, therefore, two intertwined phenomena, namely the radicalization of democracy and the radicalization of the other. It concludes by stressing that encouraging dissent and heeding contentious claims made by social movements may be one way of mitigating both types of radicalization. Embedded in the tradition of critical criminology, this paper attempts to demonstrate that only by outflanking conventional categories of analysis can the criminological community aspire to grasp such thorny contemporary phenomena
Optimism and commitment: An elementary theory of bargaining and war
We propose an elementary theory of wars fought by fully rational contenders.
Two parties play a Markov game that combines stages of bargaining with stages
where one side has the ability to impose surrender on the other. Under uncertainty
and incomplete information, in the unique equilibrium of the game, long
confrontations occur: war arises when reality disappoints initial (rational) optimism,
and it persist longer when both agents are optimists but reality proves
both wrong. Bargaining proposals that are rejected initially might eventually
be accepted after several periods of confrontation. We provide an explicit computation
of the equilibrium, evaluating the probability of war, and its expected
losses as a function of i) the costs of confrontation, ii) the asymmetry of the
split imposed under surrender, and iii) the strengths of contenders at attack
and defense. Changes in these parameters display non-monotonic effects
Using Multi-view Recognition and Meta-data Annotation to Guide a Robot's Attention
In the transition from industrial to service robotics, robots will have to deal with increasingly unpredictable and variable environments. We present a system that is able to recognize objects of a certain class in an image and to identify their parts for potential interactions. The method can recognize objects from arbitrary viewpoints and generalizes to instances that have never been observed during training, even if they are partially occluded and appear against cluttered backgrounds. Our approach builds on the implicit shape model of Leibe et al. We extend it to couple recognition to the provision of meta-dat
Intermolecular 1,3-dipolar cycloaddition of nitrile oxides with vinyl acetate and acrylonitrile
Reaction of several nitrile oxides 2, isolated from the oxidative dehydrogenation of aldoximes by chloramine-T, with vinyl acetate and acrylonitrile proceeds in better yield than if the nitrile oxides are generated in situ. Solvent effects are also considered. All new isoxazoline products have been characterized by H-1 NMR, C-13 NMR and mass spectral data
Stereoselective intramolecular 1,3-dipolar cycloadditions
An in depth account of intramolecular 1,3-dipolar cycloadditions involving dipoles such as nitrile oxides, silyl nitronates, H-nitrones, azides, and nitrilimines is presented with particular emphasis on the stereochemistry during the cyclo addition. Various methods employed for the generation of the dipoles and their applications to stereoselective synthesis are also discussed
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