Measuring the Impact of Inner City Markets on CBD Retail Sales

[Excerpt] Observers of Central Business District (CBD) retailing performance have reported many adjustments in recent decades. Sales have steadily declined, relatively and absolutely, since World War II. The function and trade area of the CBD has changed, the clientele is different, and retail establishments have adopted new locational strategies. Contributing substantially to the changing character of CBDs has been the pervasive and continuing decentralization of the metropolitan population. Nearly two decades ago, Vance (1962) conceptualized the impact of this decentralization process as one of relegating the CBD to that of (1) a seller of mass appeal goods to an inner city market and (2) a seller of specialty goods to the metropolitan market. More recently, it appears that a scaling back has also occurred in the specialty goods area. Increasingly, specialty goods sales have been sustained by those who are downtown because of employment or business

{1,2-Bis[(3,5-dimethyl-1H-pyrazol-1-yl-κN 2)meth­yl]benzene}­dichloridozinc(II)

The title zinc complex, [ZnCl2(C18H22N4)], contains a bidentate 1,2-bis(3,5-dimethyl-1H-pyrazol-1-ylmeth­yl)benz­ene ligand that binds to the zinc atom, forming a nine-membered metallocyclic ring. The geometry about the Zn atom is distorted tetra­hedral, with the largest deviation observed in the magnitude of the Cl—Zn—Cl angle. Similar distortions are observed in the cobalt analogue and related zinc compounds containing metallocyclic rings with more than six members. The copper analogue exhibits a more severe distortion of the metal coordination sphere than is observed in the title compound

Analytic Examples, Measurement Models and Classical Limit of Quantum Backflow

We investigate the backflow effect in elementary quantum mechanics - the phenomenon in which a state consisting entirely of positive momenta may have negative current and the probability flows in the opposite direction to the momentum. We compute the current and flux for states consisting of superpositions of gaussian wave packets. These are experimentally realizable but the amount of backflow is small. Inspired by the numerical results of Penz et al (M.Penz, G.Gr\"ubl, S.Kreidl and P.Wagner, J.Phys. A39, 423 (2006)), we find two non-trivial wave functions whose current at any time may be computed analytically and which have periods of significant backflow, in one case with a backwards flux equal to about 70 percent of the maximum possible backflow, a dimensionless number $c_{bm} \approx 0.04$, discovered by Bracken and Melloy (A.J.Bracken and G.F.Melloy, J.Phys. A27, 2197 (1994)). This number has the unusual property of being independent of $\hbar$ (and also of all other parameters of the model), despite corresponding to an obviously quantum-mechanical effect, and we shed some light on this surprising property by considering the classical limit of backflow. We discuss some specific measurement models in which backflow may be identified in certain measurable probabilities.Comment: 33 pages, 14 figures. Minor revisions. Published versio

Correlates of bullying behaviors among a sample of North American Indigenous adolescents

The purpose of this study was to examine the relationship between familial, educational, and psychosocial factors and bullying among 702 North American Indigenous adolescents aged 11–14 years. The study used multinomial logistic regression models to differentiate correlates of bully perpetration and victimization versus being neither and between being a perpetrator versus being a victim. Analyses reveal that being a bully victim had different correlates than being a perpetrator. Perceived discrimination was associated with increased odds of being either a victim or a perpetrator, relative to being neither. Several factors differentiated being a bully perpetrator from being a bully victim: adolescent age, parental warmth and support, depressive symptoms, anger, and school adjustment. These findings expand upon the limited understanding of the factors associated with bullying among North American Indigenous youth. Bullying intervention and prevention programs that target Indigenous adolescents should be culturally grounded and begin early within the family

Correlates of bullying behaviors among a sample of North American Indigenous adolescents

The purpose of this study was to examine the relationship between familial, educational, and psychosocial factors and bullying among 702 North American Indigenous adolescents aged 11–14 years. The study used multinomial logistic regression models to differentiate correlates of bully perpetration and victimization versus being neither and between being a perpetrator versus being a victim. Analyses reveal that being a bully victim had different correlates than being a perpetrator. Perceived discrimination was associated with increased odds of being either a victim or a perpetrator, relative to being neither. Several factors differentiated being a bully perpetrator from being a bully victim: adolescent age, parental warmth and support, depressive symptoms, anger, and school adjustment. These findings expand upon the limited understanding of the factors associated with bullying among North American Indigenous youth. Bullying intervention and prevention programs that target Indigenous adolescents should be culturally grounded and begin early within the family

Thaumasite form of sulfate attack in limestone cement mortars: A study on long term efficiency of mineral admixtures

Concrete and mortar made from limestone cement may exhibit a lack of durability due to the formation of thaumasite. The addition of minerals that improve the concrete durability is expected to slow down the formation of thaumasite. in this work the effect of natural pozzolana, fly ash, ground granulated blast-furnace slag and metakaolin on the thaumasite formation in limestone cement mortar is examined. A limestone cement, containing 15% w/w limestone, was used. Mortar specimens were prepared by replacing a part of limestone cement with the above minerals. The specimens were immersed in a 1.8% MgSO4 solution and cured at 5 and 25 degrees C. The status of the samples after a storage period of 5 years was reported based on visual inspection, compressive strength, mass measurements, ultrasonic pulse velocity measurements and analytical techniques. It is concluded that the use of specific minerals, as partial replacement of cement, inhibits thaumasite formation in limestone cement mortar. (C) 2008 Elsevier Ltd. All rights reserved

Gaps present a trade-off between dispersal and establishment that nourishes species diversity

We took advantage of two natural experiments to investigate processes that regulate tree recruitment in gaps. In the first, we examined the recruitment of small and large saplings and trees into 31 gaps resulting from treefalls occurring between 1984 and 2015 in the 2.25-ha core area of a 4-ha tree plot at Cocha Cashu in Peru. In the second, we identified the tallest saplings recruiting into 69 gaps created during a violent wind storm in February 2000. In the established tree plot, we were able to compare the composition of saplings in the disturbance zones of gaps prior to, during, and subsequent to the period of gap formation. Recruitment in gaps was compared with that in "nofall" zones, areas within the plot that had not experienced a treefall at least since the early 1980s. Our results confirmed earlier findings that a consistently high proportion (~60%) of established saplings survived gap formation. Light demanding species, as proxied by mortality rates, recruited under all conditions, but preferentially during periods of gap formation, a pattern that was especially strong among gap pioneers. Similar results were noted, separately, for small and large saplings and trees recruiting at >= 10 cm dbh. One hundred percent of previously untagged trees recruiting into gaps in the first post-disturbance census were gap pioneers, suggesting rapid development. This conclusion was strongly supported in a follow-up survey taken of 69 gaps 19 months after they had been synchronously created in a wind storm. Ten species of gap pioneers, eight of which are not normally present in the advance regeneration, had attained heights of 6-10 m in 19 months. The 10 gap pioneers were dispersed, variously, by primates, bats, birds, and wind and reached maximum frequency in different-sized gaps (range 1,000 m(2)). Both gap size and limited dispersal of zoochorous species into gaps serve as filters for establishment, creating a complex mosaic of conditions that enhances species diversity

Demonstration of a discharge pumped table-top soft-x-ray laser

Includes bibliographical references (page 2195).Includes errata.We report the first observation of large soft-x-ray amplification (gl = 7.2) in a discharge-created plasma. A fast, ~40 kA, current pulse from a compact discharge was used to excite plasma columns up to 12 cm in length in 4-mm channels, producing population inversion in the J = 0-1 line of Ne-like Ar and resulting in a gain of 0.6 cm-1 at 46.9 nm. The beam divergence was measured to be <9 mrad

Topological Reduction of 4D SYM to 2D σ\sigma--Models

By considering a (partial) topological twisting of supersymmetric Yang-Mills compactified on a 2d space with `t Hooft magnetic flux turned on we obtain a supersymmetric $\sigma$-model in 2 dimensions. For N=2 SYM this maps Donaldson observables on products of two Riemann surfaces to quantum cohomology ring of moduli space of flat connections on a Riemann surface. For N=4 SYM it maps $S$-duality to $T$-duality for $\sigma$-models on moduli space of solutions to Hitchin equations.Comment: 30 pages, harvma