Advances in Old-Fashioned Heterotic String Model Building

I review findings of various research groups regarding perturbative heterotic string model building in the last 12 months. Attention is given to recent studies of extra U(1)'s and local discrete symmetries (LDS's) in generic string models. Issues covered include the role of U(1)'s and LDS's in limiting proton decay, developments in classification of models containing anomalous U(1), and possible complications resulting from kinetic mixing between observable and hidden sector U(1)'s. Additionally, recent string-derived and string-inspired models are briefly reviewed. Talk Presented at SUSY '97.Comment: Talk presented at SUSY'97. Latex w/ espcrc2.sty, 10 pages, reference corrections and update

4-Formyl­phenyl 2,3,4,6-tetra-O-acetyl-β-d-galactopyran­oside

The galactose ring in the title compound, C21H24O11, has a chair conformation with the substituted benzene ring occupying an equatorial position. The crystal packing features C—H⋯O inter­actions that lead to the formation of supra­molecular layers in the ab plane

4-Formyl­phenyl 2,3,4,6-tetra-O-acetyl-β-d-glucopyran­oside

The pyran­oside ring in the title compound, C21H24O11, has a chair conformation with the substituted benzene ring occupying an equatorial position. The crystal packing is dominated by C—H⋯O inter­actions that lead to the formation of supra­molecular layers in the ab plane

trans-Di-chlorido-bis-(dimethyl sulfoxide-κO)bis-(4-fluoro-benzyl-κC(1))tin(IV):crystal structure and Hirshfeld surface analysis

The Sn(IV) atom in the title diorganotin compound, [Sn(C7H6F)2Cl2(C2H6OS)2], is located on a centre of inversion, resulting in the C2Cl2O2 donor set having an all-trans disposition of like atoms. The coordination geometry approximates an octa-hedron. The crystal features C-H⋯F, C-H⋯Cl and C-H⋯π inter-actions, giving rise to a three-dimensional network. The respective influences of the Cl⋯H/H⋯Cl and F⋯H/H⋯F contacts to the mol-ecular packing are clearly evident from the analysis of the Hirshfeld surface

trans-Di-chlorido-bis-(dimethyl sulfoxide-κO)bis-(4-fluoro-benzyl-κC(1))tin(IV):crystal structure and Hirshfeld surface analysis

The Sn(IV) atom in the title diorganotin compound, [Sn(C7H6F)2Cl2(C2H6OS)2], is located on a centre of inversion, resulting in the C2Cl2O2 donor set having an all-trans disposition of like atoms. The coordination geometry approximates an octa-hedron. The crystal features C-H⋯F, C-H⋯Cl and C-H⋯π inter-actions, giving rise to a three-dimensional network. The respective influences of the Cl⋯H/H⋯Cl and F⋯H/H⋯F contacts to the mol-ecular packing are clearly evident from the analysis of the Hirshfeld surface

The Russian Orthodox Church and Moscow-the Third Rome Concept

In 988, under the leadership of Kinyaz Viladimer, Russians accepted Christianity through the Patriarchate of Constantinople and entered a new phase in their history. With Christianity, the Russians were introduced to writing and, most importantly, to religious texts. At the same time, this religious conversion also led to the acceptance of the belief of chosenness, which had spread to Christianity from Judaism. Nestor, a Russian priest who lived in the 12th century, wrote in his work that although Russians were the last community to accept Christianity, they would undertake important missions in the future. He also attributed a mission to the Russian society by referring to the biblical passage that the feet will be the head and the head will be the feet. However, in the mentioned centuries, the Eastern Roman Empire was still the center of Orthodoxy. For this reason, the Russian Orthodox Church would remain for many years as a Metropolitanate under the Patriarchate of Constantinople. However, the increasing Ottoman pressure on Constantinople from the 1400s onwards created several historical opportunities for the Russians. In particular, the Byzantine agreement with the Pope of Rome in Florence in 1439 mobilized the Russian Church. Using this agreement as a pretext, Moscow severed its relations with Constantinople. In 1453, the Ottoman conquest of Constantinople, the center of the Orthodox world, opened a new page in Russian Theo-politics. Russian priests believed that Nestor's prophecy had been fulfilled and Moscow developed the concept of the Third Rome. Appearing in the 16th century, the Moscow-Third Rome concept soon became the ideological basis for the formation of the Moscow kingdom. In this article, the concept of Moscow Third Rome, which is one of the important turning points in Russian history, is analyzed through an analytical method. The background of the concept, the conditions that led to its emergence, its historical development and its reflections on the present day are emphasized

Range-wide post- and pre-breeding migratory networks of a declining Neotropical-Nearctic migratory bird, the blackpoll warbler

Identifying drivers of population declines in migratory species requires understanding how individuals are spatially distributed across periods of the annual cycle. We built and analyzed post- (fall) and pre-breeding (spring) migratory networks for the blackpoll warbler (Setophaga striata), a Neotropical-Nearctic songbird, using data from 47 light-level geolocators deployed at 11 sites in its range. At a network scale, eastern and western-breeding individuals concentrated in different stopover and wintering nodes, resulting in a distinct “crosswise” migration pattern and community structure. However, individuals from across the breeding range overlapped at several nodes characterized by high betweenness (presence along shortest paths) and time-adjusted node weight (use intensity), including nodes on the eastern coast of North America, in the southeastern U.S., and northern Colombia and Venezuela. We provide the first range-wide assessment of migratory connectivity for this declining species which will serve as an important basis for further research and conservation efforts