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Grafting poly(phenylene oxide) with poly(vinylphosphonic acid) for fuel cell membranes
Densely phosphonated electrolyte membranes were prepared from poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) grafted with poly(vinylphosphonic acid) (PVPA) side chains. In the first step, PPO was lithiated in solution at room temperature by adding n-butyllithium to form an anionic macroinitiatior. Next, diethyl vinylphosphonate (DEVP) was anionically polymerized from the lithiated sites at -78 °C. T
Testing for structural breaks in the presence of data perturbations: impacts and wavelet-based improvements
This paper investigates how classical measurement error and additive outliers (AO) influence tests for structural change based on F-statistics. We derive theoretically the impact of general additive disturbances in the regressors on the asymptotic distribution of these tests for structural change. The small sample properties in the case of classical measurement error and AO are investigated via Mo
Body Mass Index and the Risk for Crohn's Disease and Ulcerative Colitis: Data From a European Prospective Cohort Study (The IBD in EPIC Study)
OBJECTIVES: Obesity is associated with a proinflammatory state that may be involved in the etiology of inflammatory bowel disease (IBD), for which there are plausible biological mechanisms. Our aim was to perform the first prospective cohort study investigating if there is an association between obesity and the development of incident IBD. METHODS: A total of 300,724 participants were recruited in
The Swedish Family-Cancer Database 2009: prospects for histology-specific and immigrant studies
The Swedish Family-Cancer Database comprises a total of 11.8 million individuals covering the Swedish population of the past 100 years. Version VIII of the Database is described in the present article. Cancer cases were retrieved from the Swedish Cancer Registry for the period 1958-2006, including more than 1 million first primary cancers. The number of familial cancers in offspring is 14,000 when
The contribution of tephra constituents during biogenic silica determination: implications for soil and palaeoecological studies
Biogenic silica (BSi) is used as a proxy by soil scientists to identify biological effects on the Si cycle and by palaeoecologists to study environmental changes. Alkaline extractions are typically used to measure BSi in both terrestrial and aquatic environments. The dissolution properties of volcanic glass in tephra deposits and their nanocrystalline weathering products are hypothesized to overla
Prevalence of manual Strauss LBBB criteria in patients diagnosed with the automated Glasgow LBBB criteria.
About one-third of patients undergoing cardiac resynchronization therapy because of left bundle branch block (LBBB) and heart failure do not improve. Strauss et al. have developed strict criteria to more accurately define complete LBBB in this patient group. The aim of this study was to investigate the prevalence of the manual application of the Strauss criteria for LBBB (QRS≥140ms in men, ≥130ms
Coordination chemistry and hydrolysis of Fe(III) in a peat humic acid studied by X-ray absorption spectroscopy
The speciation of iron (Fe) in soils, sediments and surface waters is highly dependent on chemical interactions with natural organic matter (NOM). However, the molecular structure and hydrolysis of the Fe species formed in association with NOM is still poorly described. In this study extended X-ray absorption fine structure (EXAFS) spectroscopy was used to determine the coordination chemistry and
Drought impact on forest carbon dynamics and fluxes in Amazonia
In 2005 and 2010 the Amazon basin experienced two strong droughts', driven by shifts in the tropical hydrological regime(2) possibly associated with global climate change(3), as predicted by some global models'. Tree mortality increased after the 2005 drought(4), and regional atmospheric inversion modelling showed basin-wide decreases in CO2 uptake in 2010 compared with 2011 (ref. 5). But the resp
Rationale and Design of the 'MITOCARE' Study: A Phase II, Multicenter, Randomized, Double-Blind, Placebo-Controlled Study to Assess the Safety and Efficacy of TRO40303 for the Reduction of Reperfusion Injury in Patients Undergoing Percutaneous Coronary Intervention for Acute Myocardial Infarction
Treatment of acute ST-elevation myocardial infarction (STEMI) by reperfusion using percutaneous coronary intervention (PCI) or thrombolysis has provided clinical benefits; however, it also induces considerable cell death. This process is called reperfusion injury. The continuing high rates of mortality and heart failure after acute myocardial infarction (AMI) emphasize the need for improved strate
A taxonomic study of Melanelixia fuliginosa in Europe
For a long time it has been discussed as to whether Melanelixia fuliginosa comprises one or two species: one darker, mainly saxicolous, and one lighter, mainly corticolous. To settle the question, a morphometric and a molecular analysis were carried out and analyzed using a principal component analysis (PCA). The morphometric analysis indicates a differentiation in several characters between mater
Comparisons of Heat Transfer Enhancement of an Internal Blade Tip with Metal or Insulating Pins
Cooling methods are needed for turbine blade tips to ensure a long durability and safe operation. A common way to cool a tip is to use serpentine passages with 180-deg turn under the blade tip-cap taking advantage of the three-dimensional turning effect and impingement like flow. Improved internal convective cooling is therefore required to increase the blade tip lifetime. In the present study, au
Bat flight.
Bats are unique among extant flying animals, as they have compliant wings and an echolocation sensory system that distinguish them from birds and insects. Flying in the dark, guided by echolocation, has influenced the aerodynamics of bat flight perhaps more than previously realized and resulted in a characteristic flight that is now being revealed.
Heparin-Binding Protein: A Potential Biomarker in Sepsis? Reply
Inhibition of CXCL12 signaling attenuates the postischemic immune response and improves functional recovery after stroke.
After stroke, brain inflammation in the ischemic hemisphere hampers brain tissue reorganization and functional recovery. Housing rats in an enriched environment (EE) dramatically improves recovery of lost neurologic functions after experimental stroke. We show here that rats housed in EE after stroke induced by permanent occlusion of the middle cerebral artery (pMCAO), showed attenuated levels of
Borders, Security and (Global) Governance: Introduction to Special Issue
SBSI: an extensible distributed software infrastructure for parameter estimation in systems biology
Complex computational experiments in Systems Biology, such as fitting model parameters to experimental data, can be challenging to perform. Not only do they frequently require a high level of computational power, but the software needed to run the experiment needs to be usable by scientists with varying levels of computational expertise, and modellers need to be able to obtain up-to-date experimen
Effect of Delayed Cord Clamping on Neurodevelopment at 4 Years of Age: A Randomized Clinical Trial.
Prevention of iron deficiency in infancy may promote neurodevelopment. Delayed umbilical cord clamping (CC) prevents iron deficiency at 4 to 6 months of age, but long-term effects after 12 months of age have not been reported.
AN EXPERIMENTAL AND NUMERICAL STUDY OF FLOW AND HEAT TRANSFER IN RIBBED CHANNELS WITH LARGE RIB PITCH-TO-HEIGHT RATIOS
This paper presents an experimental and numerical study of flow and heat transfer char teristics in rectangular cross-section ribbed channels with continuous transverse ribs with large pitch-to-height ratios. Five ribs are regularly placed on the bottom wall of the channels with varied rib pitch-to-height ratios ranging from 10 to 30. The channel inlet Reynolds number ranges from 57,000 to 127,000
The Riks-Stroke story: building a sustainable national register for quality assessment of stroke care.
Background Riks-Stroke, the Swedish Stroke Register, is the world's longest-running national stroke quality register (established in 1994) and includes all 76 hospitals in Sweden admitting acute stroke patients. The development and maintenance of this sustainable national register is described. Methods Riks-Stroke includes information on the quality of care during the acute phase, rehabilitation a