Topological Photonics

Topology is revolutionizing photonics, bringing with it new theoretical discoveries and a wealth of potential applications. This field was inspired by the discovery of topological insulators, in which interfacial electrons transport without dissipation even in the presence of impurities. Similarly, new optical mirrors of different wave-vector space topologies have been constructed to support new states of light propagating at their interfaces. These novel waveguides allow light to flow around large imperfections without back-reflection. The present review explains the underlying principles and highlights the major findings in photonic crystals, coupled resonators, metamaterials and quasicrystals.Comment: progress and review of an emerging field, 12 pages, 6 figures and 1 tabl

Long-Term Relations Among Prosocial-Media Use, Empathy, and Prosocial Behavior

Despite recent growth of research on the effects of prosocial media, processes underlying these effects are not well understood. Two studies explored theoretically relevant mediators and moderators of the effects of prosocial media on helping. Study 1 examined associations among prosocial- and violent-media use, empathy, and helping in samples from seven countries. Prosocial-media use was positively associated with helping. This effect was mediated by empathy and was similar across cultures. Study 2 explored longitudinal relations among prosocial-video-game use, violent-video-game use, empathy, and helping in a large sample of Singaporean children and adolescents measured three times across 2 years. Path analyses showed significant longitudinal effects of prosocial- and violent-video-game use on prosocial behavior through empathy. Latent-growth-curve modeling for the 2-year period revealed that change in video-game use significantly affected change in helping, and that this relationship was mediated by change in empathy

PRODUCTION PERFORMANCE OF SOME WHEAT VARIETIES IN THE PEDOCLIMATE CONDITIONS FROM SCDA CARACAL

Knowing the particularities of the reaction of the new varieties and hybrids of the crop plants, under different conditions of experimentation is one of the basic activities of the experimental agricultural research and its aim is their judicious choice for cultivation in certain areas. The paper presents the production results obtained from two Romanian varieties of autumn wheat grown under pedoclimatic conditions at SCDA Caracal, under non-irrigation regime, during three years of experimentation. Taking into consideration the variations of the climatic conditions over the years of experimentation, at the same level of fertilization, the productions obtained for the two varieties of wheat recommend their cultivation in the area of the Caracal Plain

Analysis of Foreign Trade with the Main Categories of Agro-Food Products, Parallel Romania - Italy

This paper aims to study the dynamics and structure of foreign trade in agro-food products according to the combined nomenclature of Romania and Italy. In this regard, with the help of statistical data taken from databases: the National Institute of Statistics, for Romania, and the International Trade Center, for Italy, the dynamics of exports, imports, and, at the same time, the trade balance were analysed. The degree of concentration of both imported and exported products was further analysed to determine whether or not there was a concentration on a particular chapter of the Combined Nomenclature