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Data from the World Values Survey and AmericasBarometer are used in ordinal logistic models to evaluate life satisfaction in rural and urban areas in Latin America. Our findings indicate that, unlike the United States, in Latin America there is no evidence of rural–urban happiness differences. In Latin America familism is the key driving force, aspatial and transcending location. [ABSTRACT FROM AUTHOR]

Abstract: Data from the World Values Survey are used in multilevel statistical models to evaluate received theory about preferences for rural versus big-city living, as evidenced by variations in life satisfaction/happiness/utility and its converse, life dissatisfaction. The models control for individual-level determinants of life satisfaction plus such embedding circumstances as level of development and culture region. For most parts of the world there is no evidence that either rural or big-city living are associated with variations in happiness or unhappiness; personal characteristics and level of development are the key driving forces. The exceptions are in rapidly-urbanizing Asia, where life dissatisfaction is lower in big cities than elsewhere, and in higher income countries, particularly those of Anglo-Saxon heritage, where life dissatisfaction increases with big-city residence and is significantly lower in rural areas. The Asian experience is consistent with the expectations of received urban theory for regions experiencing the upswing of the urban transition and rapid rural-to-urban migration while the higher income Anglo-Saxon experience conforms with expectations about preferences for low-density living close to nature that are traits of that culture. [Copyright &y& Elsevier]

Abstract: Whether ENSO has affected U.S. macroeconomic performance has been a matter of dispute. To address the issue we explore whether there has been any co-cyclicality of ENSO fluctuations and the rates of inflation and economic growth over the 1894–1999 timespan and, failing this, whether aperiodic ENSO shocks have had any impact on these variables. Neither co-cyclicality nor aperiodic shocks are discernible. While ENSO may briefly influence the performance of particular sectors of the economy in particular regions, as documented by the previous literature, such locally-important effects vanish into the noise surrounding macroeconomic trends in an economy as large and complex as that of the U.S. [Copyright &y& Elsevier]

Abstract: Four phases of interest in the distribution of city sizes are identified and current conflict in the literature is shown to be a consequence of poorly-selected units of observation. When urban regions are properly defined, US urban growth obeys Gibrat’s Law and the city size distribution is strictly Zipfian rank-size with coefficient q =1.0. Care has to be taken with definition of the largest urban-economic regions, however; the fit in the upper tail of the distribution is best when they are recognized to be megalopolitan in scale. [Copyright &y& Elsevier]

Abstract: The domain size of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) in the bulk heterojunction (BHJ) of organic photovoltaic (OPV) devices is of great importance to the performance and lifetime of a device. This study focuses on the use of polystyrene-tethered fullerenes (PTFs) as an additive to reduce the initial domain size of PCBM as well as to mitigate the growth of these domains over time that typically results in decreased device efficiency. Films were prepared from a 1:1 mixture of P3HT:PCBM on silicon wafers to approximate a BHJ system. PTFs were added in concentrations ranging from 0 to 20%. The samples were then annealed at 150°C for varying times ranging from 5 to 60min and examined by SEM to determine the average PCBM domain sizes for each sample. As expected, the control sample containing no additive showed significant growth in the PCBM domains as the sample was annealed with a final average domain size of 290μm2. However, addition of as little as 5% PTFs produced average PCBM domain sizes after 60min of annealing of 28μm2. Addition of 20% PTF resulted in an average PCBM domain size of 2μm2. Photoluminescence spectroscopy (PL) studies were performed on the films to study their electrical properties and based on these encouraging results; devices containing these architectures were prepared. OPVs with PTFs showed an increased lifetime, and in some cases, an increase in efficiency over devices containing no PTF. [Copyright &y& Elsevier]

Background: We developed a DVD training tool to educate physicians evaluating emergency residents on accurate Standardized Direct Observation Assessment Tool (SDOT) application.Objective: Our goal was to assess whether this training video improved attendings' and senior residents' SDOT use.Methods: Participants voluntarily completed SDOT evaluations based on a scripted "test" video. A DVD with "positive" and "negative" scenarios of proper SDOT use was viewed. It included education on appropriate recording of 26 behaviors. The test scenario was viewed again and follow-up SDOTs submitted. Performances by attendings and residents on the pre- and post-test SDOTs were compared.Results: Twenty-six attendings and 26 senior residents participated. Prior SDOT experience was noted for 8 attendings and 11 residents. For 20 anchors, participants recorded observed behaviors with statistically significant difference on one each of the pretest (no. 20; p = 0.034) and post-test (no. 14; p = 0.041) SDOTs. On global competency assessments, pretest medical knowledge (p = 0.016) differed significantly between groups. The training intervention changed one anchor (no. 5; p = 0.035) and one global assessment (systems-based practice; p = 0.031) more negatively for residents. Recording SDOTs with exact agreement occurred 48.73% for attendings pretest and 54.41% post-test; resident scores were 45.86% and 49.55%, respectively. DVD exposure slightly raised attending scores (p = 0.289) and significantly lowered resident scores (p = 0.046).Conclusions: Exposure to an independently developed SDOT training video tended to raise attending scores, though without significance, while at the same time lowered senior resident scores statistically significantly. Emergency attendings' and senior residents' SDOT scoring rarely differed with significance; about half of anchor behaviors were recorded with exact agreement. This suggests senior residents, with appropriate education, may participate in SDOT assessment. [ABSTRACT FROM AUTHOR]

Thickness-dependent ordering of lamellar microdomains in symmetric polystyrene- b -poly(methyl methacrylate) (PS- b -PMMA) thin films was studied using scanning force microscopy (SFM), scanning electron microscopy (SEM), and grazing incidence small-angle X-ray scattering (GISAXS). The extent of perpendicular orientation for the lamellar microdomains on a neutral substrate was assessed at various film thicknesses around a lamella period (1 L o ) by varying the molecular weight of PS- b -PMMAs. The lateral ordering of perpendicularly oriented lamellae was evaluated with the defect distance ( D ) and orientational correlation length ( ξ ) to extract the power law relationships with film thicknesses. The lateral ordering of higher-molecular-weight (>74 kg/mol) PS- b -PMMA films is enhanced by increasing film thickness, whereas in a low-molecular-weight (50 kg/mol) PS- b -PMMA, it is enhanced by decreasing film thickness below 1 L o . [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H 2 O 2 ) detection was electrochemically performed using a non-enzymatic cobalt(III) complex ( 2 ) of an amidomacrocyclic ligand ( 1 ). We have characterized the metal complex using analytical techniques such as 1 H NMR and ESI-MS and the composite material of the catalyst supported on multiwalled carbon nanotubes (MWCNTs) with XPS and TEM. Using different carbonaceous nanomaterials, varying catalyst:nanomaterial ratio and changing the pendant groups on the ligand moiety of the complex, we found that a dichloro substituent ( 2a ) supported on MWCNTs as the most effective H 2 O 2 sensor. From these studies, a low detection limit (5.0 × 10 −8 M) and a wide detection range was obtained. Electrochemical studies indicated 2a and MWCNTs worked synergistically to detect the presence of H 2 O 2 . UV/Vis of 2a showed the disappearance of a peak at 500 nm and the emergence of a peak at 395 nm after the addition of H 2 O 2 to 2a indicating formation of an intermediate species. 2a was also able to electrochemically determine the concentration of H 2 O 2 present in several commercial products. Hence, 2a shows promising application as a non-enzymatic H 2 O 2 sensor. [ABSTRACT FROM AUTHOR]

Abstract: Background: Bleeding following percutaneous coronary intervention (PCI) is common and may lead to transfusion and death. Although previous work has examined the effect of red blood cell (RBC) transfusion in patients with coronary disease, no study had investigated whether transfusion of non-RBC components was associated with mortality following PCI. Methods: All subjects transfused in the 10days following PCI were identified using the British Columbia Cardiac and Central Transfusion Registries. Patients undergoing cardiac surgery following PCI were excluded as transfusion was assumed to be due to surgical related bleeding. Transfusion products were categorised as RBC and non-RBC comprising platelets, plasma and cryoprecipitate. Blood product use was compared according to thirty day mortality using multivariate regression and propensity adjustment for confounding variables. Results: From a total of 32,580 patients who underwent PCI, 952 patients received at least 1 blood product within 10days of PCI. Non-RBC transfusion occurred more commonly in the cohort of transfused patients dying within 30days (p<0.001). After adjustment for baseline risk, transfusion of plasma/cryoprecipitate (HR 5.17; 95% C.I. 2.87–9.32, p<0.001) and platelets (HR 2.13; 95% C.I. 1.10–4.13, p=0.03) was associated with increased 30day mortality. In a propensity risk adjusted model, transfusion of plasma/cryoprecipitate and RBC transfusion volume remained as significant predictors of 30-day mortality (p<0.001). Conclusions: Transfusion following PCI appears to be associated with an increased risk of death within 30days. We now report that transfusion with plasma rich non-RBC products may confer an additional mortality risk to patients undergoing PCI. [Copyright &y& Elsevier]

Abstract: Ethnopharmacological relevance: Because of its virulence and antibiotic resistance, Staphylococcus aureus is a more formidable pathogen now than at any time since the pre-antibiotic era. In an effort to identify and develop novel antimicrobial agents with activity against this pathogen, we have examined Gynoxys verrucosa Wedd (Asteraceae), an herb used in traditional medicine in southern Ecuador for the treatment and healing of wounds. Materials and methods: The sesquiterpene lactones leucodine (1) and dehydroleucodine (2) were extracted and purified from the aerial parts of Gynoxys verrucosa, and their structure was elucidated by spectroscopic methods and single-crystal X-ray analysis. The in vitro anti-microbial activity of Gynoxys verrucosa extracts and its purified constituents was determined against six clinical isolates including Staphylococcus aureus and Staphylococcus epidermidis strains with different drug-resistance profiles, using the microtiter broth method. Results: Compound 1 has very low activity, while compound 2 has moderate activity with MIC50s between 49 and 195μg/mL. The extract of Gynoxys verrucosa has weak activity with MIC50s between 908 and 3290μg/mL. Conclusions: We are reporting the full assignment of the 1H NMR and 13C NMR of both compounds, and the crystal structure of compound 2, for the first time. Moreover, the fact that compound 2 has antimicrobial activity and compound 1 does not, demonstrates that the exocyclic conjugated methylene in the lactone ring is essential for the antimicrobial activity of these sesquiterpene lactones. However, the weak activity observed for the plant extracts, does not explain the use of Gynoxys verrucosa in traditional medicine for the treatment of wounds and skin infections. [Copyright &y& Elsevier]

The incidence of obesity is increasing throughout the industrialized world and is a major public health concern. Some studies have shown a paradoxical protective effect of moderate obesity on outcome after percutaneous coronary intervention (PCI). The association between bleeding, body mass, and outcome is not well established and formed the basis for the present study, which examined major bleeding rates and mortality after PCI in British Columbia during a 6-year period. We identified 38,346 consecutive patients from the British Columbia Cardiac Registry who underwent PCI from 1999 to 2005. Data were cross-referenced to determine outcomes at 30 days and 1 year. Information about bleeding after PCI was obtained by cross-referencing the British Columbia Cardiac Registry with the Central Transfusion Registry. Baseline patient characteristics were compared among body mass index (BMI) categories. A clear bimodal (U-shaped) relation was seen between BMI and mortality. BMI was a potent independent predictor of mortality, particularly evident in the underweight (BMI <18.5 kg/m2; odds ratio [OR] 1.98, 95% confidence interval [CI] 1.6 to 2.5, p <0.0001) and morbidly obese (≥40 kg/m2; OR 1.61, 95% CI 1.28 to 2.08, p <0.0001) groups. Periprocedural transfusion was also associated with adverse outcome (OR 2.86, 95% CI 2.52 to 3.25, p <0.0001). Transfusion adopted the same bimodal distribution across the entire cohort. Emergent PCI and femoral access were procedural factors associated with outcome. In conclusion, major bleeding conferred an adverse long-term prognosis after PCI. Identifying demographic and procedural factors that increase risk will facilitate more accurate risk scoring of patients undergoing PCI and allow targeted bleeding-avoidance strategies. Body mass and female gender identified subgroups at much higher risk of bleeding after PCI, an observation that merits further study. [Copyright &y& Elsevier]