The structure and characteristics of photochromic dithienylethenes

Abstract. The data on X-ray diffraction analysis for dihetarylethenes with perfluorocyclopentene (F), maleic anhydride (M) and cyclobutenedione (S) bridges between thienyl fragments were summarized and their photochromic properties were discussed. It was established that benzoxazole and benzothiazole substituents in position 5 of thienyl rings are coplanar to the plane of thiophene cycles. Thienyl fragments in A form of all dithienylethenes are considerably turned relative to the plane of bridging cycle. It means that there is no conjugation between π -electrons of aromatic heterocycles and double bond of the bridge. Flattening of molecule framework and the envelope conformation of thienyl cycles because of aromaticity loss are characteristic features of the form B structure with F-bridge. In all cases (excluding the compounds with alkylthio substituents in position 2 of thiophene cycle) the photochromic transition A −→ B is observed independently of different nature and structure of functional groups

New York Yankees and Hollywood Anglos: the persistence of anglo-conformity in the American motion picture industry

Ideal types have received less attention than membership criteria in the ethnicity and nationalism literature. This article uses crowdsourced genealogical data and onomastics software to show that British Isles surnames and ancestry remain overrepresented among American actors, especially in roles connected with the national narrative. Conformity to the WASP ideal type persists despite the fact American actors are disproportionately born in Los Angeles, New York and other large cities, where British ancestry is rare. Jewish actors are overrepresented, yet many have Anglo surnames. Compared to athletes and politicians, actors are significantly more likely to have Anglo surnames, especially those in genres depicting the nation. After declining among cohorts of stars born between the 1800s and 1961, the share of British Isles surnames has stabilized and remains in the majority. We argue that despite rising diversity, this reflects the continuing importance of the Anglo-Protestant ethnic imago for American national identity

Predicting Eye Fixations on Complex Visual Stimuli Using Local Symmetry

Most bottom-up models that predict human eye fixations are based on contrast features. The saliency model of Itti, Koch and Niebur is an example of such contrast-saliency models. Although the model has been successfully compared to human eye fixations, we show that it lacks preciseness in the prediction of fixations on mirror-symmetrical forms. The contrast model gives high response at the borders, whereas human observers consistently look at the symmetrical center of these forms. We propose a saliency model that predicts eye fixations using local mirror symmetry. To test the model, we performed an eye-tracking experiment with participants viewing complex photographic images and compared the data with our symmetry model and the contrast model. The results show that our symmetry model predicts human eye fixations significantly better on a wide variety of images including many that are not selected for their symmetrical content. Moreover, our results show that especially early fixations are on highly symmetrical areas of the images. We conclude that symmetry is a strong predictor of human eye fixations and that it can be used as a predictor of the order of fixation

30 years of collaboration

We highlight some of the most important cornerstones of the long standing and very fruitful collaboration of the Austrian Diophantine Number Theory research group and the Number Theory and Cryptography School of Debrecen. However, we do not plan to be complete in any sense but give some interesting data and selected results that we find particularly nice. At the end we focus on two topics in more details, namely a problem that origins from a conjecture of Rényi and Erdős (on the number of terms of the square of a polynomial) and another one that origins from a question of Zelinsky (on the unit sum number problem). This paper evolved from a plenary invited talk that the authors gaveat the Joint Austrian-Hungarian Mathematical Conference 2015, August 25-27, 2015 in Győr (Hungary)

History, Commemoration, and Belief: Abraham Lincoln in American Memory, 1945-2001

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91765/1/Schuman-History_Commemoration_Belief.pd