Climatic Regions of the Canadian Arctic Islands

As a result of a comprehensive assessment of the climate of the Canadian Arctic Islands and adjacent waters, five climatic regions were identified. The regional boundaries were delineated by an analysis of the influence of the major climatic controls while further regional subdivisions were arrived at through consideration of the fields of the standard observed meteorological elements. Short discussions of the climatic characteristics of each sub-region are given and tables outlining values of selected climatic elements are presented. A brief discussion of climatic change across the entire area is included.Key words: Canadian Arctic Islands, climate, climatic change, meteorolog

City size and academic focus: Exploring trends in Canadian urban geography, planning and policy literature

Between 1996 and 2001 almost half of the cities in Canada lost population. This uneven pattern of growth prompted an examination of the English-language urban geography, planning and policy-related academic literature, which determined that Canadian urban academic journals fixated on large, growing metropolitan areas. Revisiting this literature a decade later, large cities have continued to dominate the academic discourse. Although articles dedicated to smaller and mid-sized cities are still relatively underrepresented in the literature, research focusing on more than one size of urban area has grown tremendously reflecting an emerging interest in regional connectivity and a rise in the perception of urban areas as systems, rather than individual entities

Interface modes of two-dimensional composite structures

The surface modes of a composite consisting of aligned metallic wires with square cross sections are investigated, on the basis of photonic band structure calculations. The effective long-wavelength dielectric response function is computed, as a function of the filling fraction. The dependence of the optical absorption on the shape of the wires and the polarization of light is discussed, and the effect of sharp corners analyzed. The effect of the interaction between the wires on the localization of surface plasmons is also addressed.Comment: 12 pages, 4 figures, to appear in Surf. Sc

Electron energy loss and induced photon emission in photonic crystals

The interaction of a fast electron with a photonic crystal is investigated by solving the Maxwell equations exactly for the external field provided by the electron in the presence of the crystal. The energy loss is obtained from the retarding force exerted on the electron by the induced electric field. The features of the energy loss spectra are shown to be related to the photonic band structure of the crystal. Two different regimes are discussed: for small lattice constants $a$ relative to the wavelength of the associated electron excitations $\lambda$, an effective medium theory can be used to describe the material; however, for $a\sim\lambda$ the photonic band structure plays an important role. Special attention is paid to the frequency gap regions in the latter case.Comment: 12 pages, 7 figure

Information erasure and the generalized second law of black hole thermodynamics

We consider the generalized second law of black hole thermodynamics in the light of quantum information theory, in particular information erasure and Landauer’s principle (namely, that erasure of information produces at least the equivalent amount of entropy). A small quantum system outside a black hole in the Hartle-Hawking state is studied, and the quantum system comes into thermal equilibrium with the radiation surrounding the black hole. For this scenario, we present a simple proof of the generalized second law based on quantum relative entropy. We then analyze the corresponding information erasure process, and confirm our proof of the generalized second law by applying Landauer’s principle

Non-perturbative momentum dependence of the coupling constant and hadronic models

Models of hadron structure are associated with a hadronic scale which allows by perturbative evolution to calculate observables in the deep inelastic region. The resolution of Dyson-Schwinger equations leads to the freezing of the QCD running coupling (effective charge) in the infrared, which is best understood as a dynamical generation of a gluon mass function, giving rise to a momentum dependence which is free from infrared divergences. We use this new development to understand why perturbative treatments are working reasonably well despite the smallness of the hadronic scale.Comment: Changes in Acknowledgments and PACS number

A Precious Bequest: Contemporary Research with the WPA-CCC Collections from Moundville, Alabama *

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72459/1/j.1749-6632.1981.tb28184.x.pd

Nonextensive thermal sources of cosmic rays?

The energy spectrum of cosmic rays (CR) exhibits power-like behavior with a very characteristic "knee" structure. We consider a possibility that such a spectrum could be generated by some specific nonstatistical temperature fluctuations in the source of CR with the "knee" structure reflecting an abrupt change of the pattern of such fluctuations. This would result in a generalized nonextensive statistical model for the production of CR. The possible physical mechanisms leading to these effects are discussed together with the resulting chemical composition of the CR, which follows the experimentally observed abundance of nuclei.Comment: 16 pages, 3 figures, rewritten and updated version, to be published in Centr. Eur. J. Phy

The strategic calculus of terrorism: Substitution and competition in the Israel—Palestine conflict

Previous work on the dynamics of conflicts where we see terrorism has tended to focus on whether we see shifts in attack mode following government countermeasures. We contend that many factors other than counterinsurgency can influence whether groups resort to terrorism, including competition between groups, as well as their relationship to public opinion and other political events. Hence, understanding terrorist tactics in prolonged conflicts with multiple actors requires us to consider a more general framework of innovation, imitation, competition and dependence between actors. We use disaggregated data on terrorist attacks, counterterrorism and public opinion in the Israel—Palestine conflict to jointly evaluate predictions derived from several conventional theories of strategic behaviour. We find that the strategic calculus of Palestinian groups is complex and cannot be treated as time invariant. Our results suggest that factors such as the degree of public support, inter-group competition, the anticipation of countermeasures and non-trivial non-violent payoffs have an observable effect on the strategic behaviour of the Palestinian groups, and that structural relationships are often far from constant over time. </jats:p

Short-term quality of life after myomectomy for uterine fibroids from the compare-uf fibroid registry

Background Uterine fibroids may decrease quality of life in a significant proportion of affected women. Myomectomy offers a uterine-sparing treatment option for patients with uterine fibroids that can be performed abdominally, laparoscopically (with or without robotic assistance), and hysteroscopically. Quality of life information using validated measures for different myomectomy routes, especially hysteroscopic myomectomy, is limited. Objective To compare women’s perception of their short-term health-related quality of life measures and reported time to return to usual activities and return to work for different routes of myomectomy. Materials and Methods Comparing Options for Management: Patient-centered Results for Uterine Fibroids (COMPARE-UF) is a prospective nationwide fibroid registry that enrolled premenopausal women seeking treatment for uterine fibroids at 8 clinical sites. For this analysis, we included women undergoing hysteroscopic, abdominal, or laparoscopic myomectomy who completed the postprocedure questionnaire scheduled between 6 and 12 weeks after surgery. Health-related quality of life outcomes, such as pain, anxiety, and return to usual activitie, were assessed for each route. The hysteroscopic myomectomy group had large differences in demographics, fibroid number, and uterine size compared to the other groups; thus, a direct comparison of quality of life measures was performed only for abdominal and laparoscopic approaches after propensity weighting. Propensity weighting was done using 24 variables that included demographics, quality of life baseline measures, and fibroid and uterine measurements. Results A total of 1206 women from 8 COMPARE-UF sites underwent myomectomy (338 hysteroscopic, 519 laparoscopic, and 349 abdominal). All women had substantial improvement in short-term health-related quality of life and symptom severity scores, which was not different among groups. Average symptom severity scores decreased about 30 points in each group. Return to usual activities averaged 0 days (interquartile range, 0–14 days) for hysteroscopic myomectomy, 21 days (interquartile range, 14–28 days) for laparoscopic myomectomy, and 28 days (interquartile range, 14–35 days) for abdominal myomectomy. After propensity adjustment, quality of life outcomes in the laparoscopic and abdominal myomectomy groups were similar except for more anxiety in the laparoscopic myomectomy group and slightly more pain in the abdominal myomectomy group. After propensity weighting, return to usual activities favored laparoscopic compared to abdominal procedures; median time was the same at 21 days, but the highest quartile of women in the abdominal group needed an additional week of recovery (interquartile range,14.0–28.0 for laparoscopic versus 14.0–35.0 for abdominal, P < .01). Time to return to work was also longer in the abdominal arm (median, 22 days; interquartile range, 14–40 days, versus median, 42; interquartile range, 27–56). Conclusion Women who underwent myomectomy had substantial improvement in health-related quality of life, regardless of route of myomectomy. After propensity weighting, abdominal myomectomy was associated with a nearly 2-week longer time to return to work than laparoscopic myomectomy