Control of Dynamical Localization

Control over the quantum dynamics of chaotic kicked rotor systems is demonstrated. Specifically, control over a number of quantum coherent phenomena is achieved by a simple modification of the kicking field. These include the enhancement of the dynamical localization length, the introduction of classical anomalous diffusion assisted control for systems far from the semiclassical regime, and the observation of a variety of strongly nonexponential lineshapes for dynamical localization. The results provide excellent examples of controlled quantum dynamics in a system that is classically chaotic and offer new opportunities to explore quantum fluctuations and correlations in quantum chaos.Comment: 9 pages, 7 figures, to appear in Physical Review

An Integrative Theory Addressing Cyberharassment in the Light of Technology-Based Opportunism

Scholars are increasingly calling for a deeper understanding of cyberharassment (CH) with the goal of devising policies, procedures, and technologies to mitigate it. Accordingly, we conducted CH research that (1) integrated social learning theory (SLT) and self-control theory (SCT); (2) empirically studied this model with two contrasting samples, experienced cyberharassers and less experienced cyberharassers; and (3) conducted post hoc tests to tease out the differences between the two samples. We show that for less experienced cyberharassers, CH is largely a social-psychological-technological phenomenon; whereas, for experienced cyberharassers, CH is primarily a psychological-technological phenomenon. Our study makes a threefold contribution: (1) it shows the value of integrating two theories in a holistic and parsimonious manner to explain CH; (2) it shows that SCT alone is a more relevant framework for experienced cyberharassers, whereas a combination of SCT and SLT better explains less experienced cyberharassers; and (3) it reveals that the role of technology in fostering CH is crucial, regardless of the sample. The differential, yet consistent, findings demonstrate that addressing CH is contingent upon not only identifying theoretical approaches but also identifying the particular samples to which these theoretical approaches will be more suitable. Of several implications for practice, the most important may be that anonymity, asynchronicity, and lack of monitoring are the technology choices that foster CH, and thus these should be mitigated in designing social media and other communication technologies

A systematic survey of floral nectaries

The construction of classifications, as well as the understanding of biological diversity, depends upon a careful comparison of attributes of the organisms studied (Stuessy, 1990). It is widely known that data from diverse sources showing differences from taxon to taxon are of systematic significance. Dur-ing the 20th century, systematists have emphasized that their discipline involves a synthesis of all knowledge (Stevens, 1994) or, in other words, the variation of as many relevant characters as possible should be incorporated into the natural system to be constructed. The extent to which particular characters are constant or labile will determine their usefulness to syste-matics. In general, more conservative characters will be valuable in defining families and orders, whereas more labile characters may be useful at the ge-neric and specific levels (Webb, 1984). There is no doubt that floral characters are among the most used in the classification of flowering plants. At the same time, they constitute essential features in diagnostic keys to taxa in both taxonomic treatments and Floras (Cronquist, 1981, 1988).Fil: Bernardello, Gabriel Luis Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin