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In the historiography of the Jewish diaspora in early modern Europe and under Nazism, the sociology of the black American experience in the twentieth-century metropolis, and the anthropology of ethnic outcasts in East Asia and Africa, the term ghetto, among other things, variously denotes a bounded urban ward. A brief recapitulation of the strange career of "the ghetto" in American society and social science, which has dominated inquiry into the topic both quantitatively and thematically, suffices to illustrate its semantic instability and dependency on the whims and worries of urban rulers. African Americans were forcibly funneled into reserved districts that quickly turned homogeneously black as they expanded and consolidated. They had to seek refuge inside the bounded perimeter of the Black Belt and to endeavor to develop in it a network of separate institutions to procure the basic needs of the castaway community. Indeed, in the case of African Americans, ghettoization, class differentiation, and collective enrichment proceeded apace.
The atmosphere and its manifold changes have held fascination for men and women ever since human beings have trod this Earth. Its study played an integral role in the evolution of natural philosophy from which all of our present sciences have sprung.F. Sherwood Rowland, Nobel Prize Banquet Speech, 1995
Chaos-periodicity transitions are studied within the framework of a one-dimensional CNN which are qualitatively similar to some brian-like transitions described in the literature. The nonlinearity of each cell is designed such that chaotic and periodic regimes coexist at the cell level. When a coupling between cells is considered, transition waves from chaotic behavior into a periodic one are observed to propagate along the one-dimensional array. The signals measured are qualitatively similar to some EEG measurements in biology. Here we present the study of these transitions for different types of couplings and parameters.
This corrects the article DOI: 10.1103/PhysRevLett.115.267201.
The objectives of this study were to investigate the influence of ethylene addition on the hydrogenation of CO over Ru/SiO/sub 2/ and to compare the product distribution obtained with those for CO hydrogenation in the absence of ethylene and ethylene homologation in the absence of CO. To enable identification of the source of carbon in the products, /sup 13/C-labeled CO and unlabeled C/sub 2/H/sub 4/ were used. Products were analyzed by isotope-ratio gas chromatography-mass spectrometry. Among the issues investigated were the influence of ethylene addition on the reactions of CO and the participation of ethylene in processes of hydrocarbon chain initiation and growth. The influence of ethylene addition on methane formation was also examined.
By exploiting the new concepts of CA characteristic functions and their associated attractor time-τ maps, a complete characterization of the long-term time-asymptotic behaviors of all 256 one-dimensional CA rules are achieved via a single "probing" random input signal. In particular, the graphs of the time-1 maps of the 256 CA rules represent, in some sense, the generalized Green's functions for Cellular Automata. The asymptotic dynamical evolution on any CA attractor, or invariant orbit, of 206 (out of 256) CA rules can be predicted precisely, by inspection. In particular, a total of 112 CA rules are shown to obey a generalized Bernoulli σ τ -shift rule, which involves the shifting of any binary string on an attractor, or invariant orbit, either to the left, or to the right, by up to 3 pixels, and followed possibly by a complementation of the resulting bit string. The most intriguing result reported in this paper is the discovery that the four Turing-universal rules [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text], and only these rules, exhibit a 1/f power spectrum.
The International Monetary Fund is a controversial institution whose interventions regularly provoke passionate reactions. We will argue that there is an important role for the IMF in helping to solve information, commitment, and coordination problems with significant implications for the stability of national economies and the international monetary and financial system. In executing these functions, the effectiveness of the IMF, like that of a football referee, depends on whether the players see it as competent and impartial. We will argue that the Fund’s perceived competence and impartiality, and hence its effectiveness, are limited by its failure to meet four challenges—concerning the quality of it's surveillance (of individual countries, groups of countries, and the global system); the relevance of conditionality in loan contracts; the utility of the Fund’s approach to debt problems; and the Fund’s failure to adopt a system of governance that gives appropriate voice to different stakeholders. These problems of legitimacy will have to be addressed in order for the IMF to play a more effective role in the 21st century.
