Reanalysis-driven climate simulation over CORDEX North America domain using the Canadian Regional Climate Model, version 5: model performance evaluation

The performance of reanalysis-driven Canadian Regional Climate Model, version 5 (CRCM5) in reproducing the present climate over the North American COordinated Regional climate Downscaling EXperiment domain for the 1989–2008 period has been assessed in comparison with several observation-based datasets. The model reproduces satisfactorily the near-surface temperature and precipitation characteristics over most part of North America. Coastal and mountainous zones remain problematic: a cold bias (2–6 °C) prevails over Rocky Mountains in summertime and all year-round over Mexico; winter precipitation in mountainous coastal regions is overestimated. The precipitation patterns related to the North American Monsoon are well reproduced, except on its northern limit. The spatial and temporal structure of the Great Plains Low-Level Jet is well reproduced by the model; however, the night-time precipitation maximum in the jet area is underestimated. The performance of CRCM5 was assessed against earlier CRCM versions and other RCMs. CRCM5 is shown to have been substantially improved compared to CRCM3 and CRCM4 in terms of seasonal mean statistics, and to be comparable to other modern RCMs.

Peak Last Glacial weathering intensity on the North American continent recorded by the authigenic Hf isotope composition of North Atlantic deep-sea sediments

We have retrieved radiogenic hafnium (Hf) isotope compositions (ɛHf) from authigenic Fe–Mn oxyhydroxides of deep northwest Atlantic sediments deposited over the past 26 ka to investigate the oceanic evidence of changes in dissolved weathering inputs from NE America during the last deglaciation. The extraction of seawater-derived Hf isotopic compositions from Fe–Mn oxyhydroxides is not a standard procedure. Comparisons between the Al/Hf ratios and Hf isotopic compositions of the chemically extracted authigenic phase on the one hand, and those of the corresponding detrital fractions on the other, provide evidence that the composition of past seawater has been reliably obtained for most sampled depths with our leaching procedures. This is endorsed most strongly by data for a sediment core from 4250 m water depth at the deeper Blake Ridge, for which consistent replicates were produced throughout. The Hf isotopic composition of the most recent sample in this core also closely matches that of nearby present day central North Atlantic seawater. Comparison with previously published seawater Nd and Pb isotope compositions obtained on the same cores shows that both Hf and Pb were released incongruently during incipient chemical weathering, but responded differently to the deglacial retreat of the Laurentide Ice Sheet. Hafnium was released more congruently during peak glacial conditions of the Last Glacial Maximum (LGM) and changed to typical incongruent interglacial ɛHf signatures either during or shortly after the LGM. This indicates that some zircon-derived Hf was released to seawater during the LGM. Conversely, there is no clear evidence for an increase in the influence of weathering of Lu-rich mineral phases during deglaciation, possibly since relatively unradiogenic Hf contributions from feldspar weathering were superimposed. While the authigenic Pb isotope signal in the same marine sediment samples traced peak chemical weathering rates on continental North America during the transition to the Holocene a similar incongruent excursion is notably absent in the Hf isotope record. The early change towards more radiogenic ɛHf in relation to the LGM may provide direct evidence for the transition from a cold-based to a warm-based Laurentide Ice Sheet on the Atlantic sector of North America.

Clonal spread of methicillin-resistant Staphylococcus pseudintermedius in Europe and North America: an international multicentre study

OBJECTIVES: The aim of this study was to determine the phenotypic and genotypic resistance profiles of methicillin-resistant Staphylococcus pseudintermedius (MRSP) and to examine the clonal distribution in Europe and North America. METHODS: A total of 103 MRSP isolates from dogs isolated from several countries in Europe, the USA and Canada were characterized. Isolates were identified by PCR-restriction fragment length polymorphism (RFLP), antimicrobial susceptibility was determined by broth dilution or gradient diffusion, and antimicrobial resistance genes were detected using a microarray. Genetic diversity was assessed by multilocus sequence typing (MLST), PFGE and spa typing. Staphylococcal cassette chromosome mec (SCCmec) elements were characterized by multiplex PCR. RESULTS: Thirteen different sequence types (STs), 18 PFGE types and 8 spa types were detected. The hybrid SCCmec element II-III described in a MRSP isolate was present in 75 (72.8%) isolates. The remaining isolates either had SCCmec type III (n=2), IV (n=6), V (n=14) or VII-241 (n=4) or were non-typeable (n=2). The most common genotypes were ST71(MLST)-J(PFGE)-t02(spa)-II-III(SCCmec) (56.3%) and ST68-C-t06-V (12.6%). In addition to mecA-mediated beta-lactam resistance, isolates showed resistance to trimethoprim [dfr(G)] (90.3%), gentamicin/kanamycin [aac(6')-Ie-aph(2')-Ia] (88.3%), kanamycin [aph(3')-III] (90.3%), streptomycin [ant(6')-Ia] (90.3%), streptothricin (sat4) (90.3%), macrolides and/or lincosamides [erm(B), lnu(A)] (89.3%), fluoroquinolones (87.4%), tetracycline [tet(M) and/or tet(K)] (69.9%), chloramphenicol (cat(pC221)) (57.3%) and rifampicin (1.9%). CONCLUSIONS: Two major clonal MRSP lineages have disseminated in Europe (ST71-J-t02-II-III) and North America (ST68-C-t06-V). Regardless of their geographical or clonal origin, the isolates displayed resistance to the major classes of antibiotics used in veterinary medicine and thus infections caused by MRSP isolates represent a serious therapeutic challenge.

HIV treatment response and prognosis in Europe and North America in the first decade of highly active antiretroviral therapy: a collaborative analysis

BACKGROUND: Highly active antiretroviral therapy (HAART) for the treatment of HIV infection was introduced a decade ago. We aimed to examine trends in the characteristics of patients starting HAART in Europe and North America, and their treatment response and short-term prognosis. METHODS: We analysed data from 22,217 treatment-naive HIV-1-infected adults who had started HAART and were followed up in one of 12 cohort studies. The probability of reaching 500 or less HIV-1 RNA copies per mL by 6 months, and the change in CD4 cell counts, were analysed for patients starting HAART in 1995-96, 1997, 1998, 1999, 2000, 2001, and 2002-03. The primary endpoints were the hazard ratios for AIDS and for death from all causes in the first year of HAART, which were estimated using Cox regression. RESULTS: The proportion of heterosexually infected patients increased from 20% in 1995-96 to 47% in 2002-03, and the proportion of women from 16% to 32%. The median CD4 cell count when starting HAART increased from 170 cells per muL in 1995-96 to 269 cells per muL in 1998 but then decreased to around 200 cells per muL. In 1995-96, 58% achieved HIV-1 RNA of 500 copies per mL or less by 6 months compared with 83% in 2002-03. Compared with 1998, adjusted hazard ratios for AIDS were 1.07 (95% CI 0.84-1.36) in 1995-96 and 1.35 (1.06-1.71) in 2002-03. Corresponding figures for death were 0.87 (0.56-1.36) and 0.96 (0.61-1.51). INTERPRETATION: Virological response after starting HAART improved over calendar years, but such improvement has not translated into a decrease in mortality.

Bloodstream infections in pediatric ECLS: usefulness of daily blood culture monitoring and predictive value of biological markers. The British Columbia experience

INTRODUCTION: The incidence of bloodstream infection (BSI) in extracorporeal life support (ECLS) is reported between 0.9 and 19.5%. In January 2006, the Extracorporeal Life Support Organization (ELSO) reported an overall incidence of 8.78% distributed as follows: respiratory: 6.5% (neonatal), 20.8% (pediatric); cardiac: 8.2% (neonatal) and 12.6% (pediatric). METHOD: At BC Children's Hospital (BCCH) daily surveillance blood cultures (BC) are performed and antibiotic prophylaxis is not routinely recommended. Positive BC (BC+) were reviewed, including resistance profiles, collection time of BC+, time to positivity and mortality. White blood cell count, absolute neutrophile count, immature/total ratio, platelet count, fibrinogen and lactate were analyzed 48, 24 and 0 h prior to BSI. A univariate linear regression analysis was performed. RESULTS: From 1999 to 2005, 89 patients underwent ECLS. After exclusion, 84 patients were reviewed. The attack rate was 22.6% (19 BSI) and 13.1% after exclusion of coagulase-negative staphylococci (n = 8). BSI patients were significantly longer on ECLS (157 h) compared to the no-BSI group (127 h, 95% CI: 106-148). Six BSI patients died on ECLS (35%; 4 congenital diaphragmatic hernias, 1 hypoplastic left heart syndrome and 1 after a tetralogy repair). BCCH survival on ECLS was 71 and 58% at discharge, which is comparable to previous reports. No patient died primarily because of BSI. No BSI predictor was identified, although lactate may show a decreasing trend before BSI (P = 0.102). CONCLUSION: Compared with ELSO, the studied BSI incidence was higher with a comparable mortality. We speculate that our BSI rate is explained by underreporting of "contaminants" in the literature, the use of broad-spectrum antibiotic prophylaxis and a higher yield with daily monitoring BC. We support daily surveillance blood cultures as an alternative to antibiotic prophylaxis in the management of patients on ECLS.

Alveolar hydatid disease (Echinococcus multilocularis) in the liver of a Canadian dog in British Columbia, a newly endemic region.

An adult dog that lived in central British Columbia was examined because of a history of lethargy and vomiting. Histology, immunohistochemistry, and polymerase chain reaction (PCR) examination of a hepatic mass confirmed the presence of an alveolar hydatid cyst, the first description of Echinococcus multilocularis in British Columbia. We provide recommendations for case management and remind practitioners in endemic areas of western Canada that dogs can serve as definitive and, rarely, intermediate hosts for E. multilocularis.

Saving the Australian War Effort in 1916? The Significance and Impact of Global Climatic Conditions and Pests on William Morris Hughes’ Negotiations with the British Government

Taking up the thesis of Dipesh Chakrabarty (2009) that human history (including cultural history) on the one hand and natural history on the other must be brought into conversation more than has been done so in the past, this presentation will focus more closely on the significance and the impact of global climatic conditions and pests on the negotiations that Australian Prime Minister William Morris Hughes carried on with the British government between March and November 1916. Whereas Australia had been able to sell most of its produce in 1914 and 1915 the situation looked more serious in 1916, not least due to the growing shortage in shipping. It was therefore imperative for the Australian government to find a way to solve this problem, not least because it wanted to keep up its own war effort at the pace it had been going so far. In this context intentions to make or press ahead with a contribution to a war perceived to be more total those of the past interacted with natural phenomena such as the declining harvest in many parts of the world in 1916 as a consequence of climatic conditions as well as pests in many parts of the world.

Policy Change in Comparative Contexts: Applying the Advocacy Coalition Framework Outside of Western Europe and North America

The advocacy coalition framework (ACF) is one of the most frequently applied theories of the policy process. Most applications have been in Western Europe and North America. This article provides an overview of the ACF, summarizes existing applications outside of Western Europe and North America, and introduces the special issue that features applications of the ACF in the Philippines, China, India, and Kenya. This article concludes with an argument for the continued application of the ACF outside of Western Europe and North America and a research agenda for overcoming challenges in using the ACF in comparative public policy research.