Some Greek and bilingual Arab-Byzantine bronze coins of Damascus and Hims-Emesa: some new examples of iconography and palaeography, with reference to some Byzantine issues of the late 6th and 7th centuries

There is practically nothing in the historical sources about his having shown an interest in minting bronze coins. (WALKER 1956: p. xxv) There has been some discussion about the issuing authority and chronology of the bronze coinage of Mu‘$wiya’s forty years as governor and caliph. The first bronze issues of urban mints have a terminus ante quem in the last years of his governorship, that is, in the 650s CE, to judge from an apparent hoard edited by Phillips and Goodman. (PHILLIPS-GOODMAN 1997) The earliest forms of this coinage have been called Type I, Pseudo- Byzantine or ‘imitative’ issues, which Tony Goodwin has divided into nine distinct series, Types A-I (GOODWIN 2005: pp. 16-17) An important series of these, Type B, imitations – often crudely – the obverse of Herakeios’ coins of Cyprus bearing the triple imperial image of Herakleios, Herakleios Constantine and Martina (HAHN 1981: 198a-b. FOSS 2008, nos. 3-4. ALBUM-GOODWIN 2002: nos. 505-506. GOODWIN 2005: no. 2). A more extensive series, Goodwin’s Types I D-F, bears the obverse image of emperor Constans II copied from the standard bronze coinage of the mint of Constantinople in first eight years of his reign

Macroeconomic Synchronization and Monetary Unions: Is the Euro Area more Synchronous than other Monetary Unions and are Monetary Unions more Synchronous than non-Monetary Unions?

Within currency unions, the conventional wisdom is that there should be a high degree of macroeconomic synchronicity between the constituent parts of the union. But this has not been tested compared to a base sample of countries that do not belong to a monetary union, so this paper endeavors to do exactly that. Although the US is probably one of the longest standing monetary unions in existence, there are others such as Canada and Australia, which have similar federalist structures and relatively independent States or Provinces. In this paper we take euro area data, US State macro data, Canadian provincial data and Australian state data �namely real Gross State Product (GSP), the GSP de�ator and unemployment data �and use techniques relating to recurrence plots to measure the degree of synchronicity of movement over time. The results are expected to show that for the most part monetary unions are more synchronous than non-monetary unions and that the euro area data is highly synchronous, particularly since the �financial crisis, compared to other monetary unions

A Near-Infrared Study of the Stellar Cluster: [DBS2003] 45

We present a multi-wavelength photometric and spectroscopic study of a newly discovered candidate cluster [DBS2003] 45. Our H, Ks photometry confirms that [DBS2003] 45 is a cluster. An average visual extinction Av 7.1+/-0.5 is needed to fit the cluster sequence with a model isochrone. Low resolution spectroscopy indicates that half a dozen early B and at least one late O type giant stars are present in the cluster. We estimate the age of the cluster to be between 5 and 8 Myr based on spectroscopic analysis. Assuming an age of 6 Myr, we fit the observed mass function with a power law, N(M) M^(-Gamma), and find an index Gamma 1.27+/-0.15, which is consistent with the Salpeter value. We estimate the total cluster mass is around 1000 solar masses by integrating the derived mass function between 0.5 and 45 solar masses. Both mid-infrared and radio wavelength observations show that a bubble filled with ionized gas is associated with the cluster. The total ionizing photon flux estimated from radio continuum measurements is consistent with the number of hot stars we detected. Infrared bright point sources along the rim of the bubble suggest that there is triggered star formation at the periphery of the HII region.Comment: 12 pages, 10 figures, 2 tables. Accepted by ApJ, a typo in the Abstract correcte

Evidence for DNA-mediated nuclear compartmentalization distinct from phase separation.

RNA Polymerase II (Pol II) and transcription factors form concentrated hubs in cells via multivalent protein-protein interactions, often mediated by proteins with intrinsically disordered regions. During Herpes Simplex Virus infection, viral replication compartments (RCs) efficiently enrich host Pol II into membraneless domains, reminiscent of liquid-liquid phase separation. Despite sharing several properties with phase-separated condensates, we show that RCs operate via a distinct mechanism wherein unrestricted nonspecific protein-DNA interactions efficiently outcompete host chromatin, profoundly influencing the way DNA-binding proteins explore RCs. We find that the viral genome remains largely nucleosome-free, and this increase in accessibility allows Pol II and other DNA-binding proteins to repeatedly visit nearby DNA binding sites. This anisotropic behavior creates local accumulations of protein factors despite their unrestricted diffusion across RC boundaries. Our results reveal underappreciated consequences of nonspecific DNA binding in shaping gene activity, and suggest additional roles for chromatin in modulating nuclear function and organization

Zinc released from olfactory bulb glomeruli by patterned electrical stimulation of the olfactory nerve

Zinc is a trace element with a multitude of roles in biological systems including structural and cofactor functions for proteins. Although most zinc in the central nervous system (CNS) is protein bound, the CNS contains a pool of mobile zinc housed in synaptic vesicles within a subset of neurons. Such mobile zinc occurs in many brain regions, such as the hippocampus, hypothalamus, and cortex, but the olfactory bulb (OB) contains one of the highest such concentrations in the CNS. Zinc is distributed throughout the OB, with the glomerular and granule cell layers containing the highest levels. Here, we visualize vesicular zinc in the OB using zinc-responsive fluorescent probes developed by one of us. Moreover, we provide the first demonstration that vesicular pools of zinc can be released from olfactory nerve terminals within individual glomeruli by patterned electrical stimulation of the olfactory nerve designed to mimic the breathing cycle in rats. We also provide electrophysiological evidence that elevated extracellular zinc potentiates α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor-mediated synaptic events. AMPA receptors are required for the synchronous activation of neurons within individual OB glomeruli, and zinc-mediated potentiation leads to enhanced synaptic summation.National Institute of General Medical Sciences (U.S.) (Grant GM065519)Florida State University. Program in Neuroscience (Council on Research and Creativity

A Low Progenitor Mass for the Magnetar SGR1900+14

Magnetars are young neutron stars with extreme magnetic fields (B>10(exp 14)-10(exp 15) G). How these fields relate to the properties of their progenitor stars is not yet clearly established. However, from the few objects with initial mass estimates it has been suggested that a very massive progenitor star (M(sub prog) >40M ) is required to produce a magnetar. Here we report that the initial progenitor star mass of the magnetar SGR 1900+14 was a factor of two lower than this limit, M(sub prog)=17+/-1M . Our results strongly contradict the prevalent hypothesis that only very massive stars can produce magnetars. Instead, we favour the "fossil-field" model as a possible explanation of the origin of these extreme magnetic fields

The progenitor mass of the magnetar SGR1900+14

Magnetars are young neutron stars with extreme magnetic fields (B > 10^{14}-10^{15}G). How these fields relate to the properties of their progenitor stars is not yet clearly established. However, from the few objects associated with young clusters it has been possible to estimate the initial masses of the progenitors, with results indicating that a very massive progenitor star (M_prog >40Msun) is required to produce a magnetar. Here we present adaptive-optics assisted Keck/NIRC2 imaging and Keck/NIRSPEC spectroscopy of the cluster associated with the magnetar SGR 1900+14, and report that the initial progenitor star mass of the magnetar was a factor of two lower than this limit, M_prog=17 \pm 2 Msun. Our result presents a strong challenge to the concept that magnetars can only result from very massive progenitors. Instead, we favour a mechanism which is dependent on more than just initial stellar mass for the production of these extreme magnetic fields, such as the "fossil-field" model or a process involving close binary evolution.Comment: 9 pages, 8 figs. Accepted to Ap

Multiwavelength Observations of Massive Stellar Cluster Candidates in the Galaxy

The Galaxy appears to be richer in young, massive stellar clusters than previously known, due to advances in infrared surveys which have uncovered deeply embedded regions of star formation. Young, massive clusters can significantly impact the surrounding interstellar medium (ISM) and hence radio observations can also be an important tracer of their activity. Several hundred cluster candidates are now known by examining survey data. Here we report on multiwavelength observations of six of these candidates in the Galaxy. We carried out 4.9 and 8.5 GHz VLA observations of the radio emission associated with these clusters to obtain the physical characteristics of the surrounding gas, including the Lyman continuum photon flux and ionized gas mass. Spitzer Infrared Array Camera observations were also made of these regions, and provide details on the stellar population as well as the dust continuum and polycyclic aromatic hydrocarbon emission. When compared to the known young, massive clusters in the Galaxy, the six cluster candidates have less powerful Lyman ionizing fluxes and ionize less of the H II mass in the surrounding ISM. Therefore, these cluster candidates appear to be more consistent with intermediate-mass clusters (10^3-10^4 Msun).Comment: 39 pages, 20 figures. Accepted in the Astronomical Journal; to be published Fall 201