Low-temperature electrochemical CO reduction has demonstrated high selectivity for CO when devices are operated with pure CO streams. However, there is currently a dearth of knowledge for systems operating below 30% CO, a regime interesting for coupling electrochemical devices with CO point sources. Here we examine the influence of ionomer chemistry and cell operating conditions on the CO selectivity at low CO concentrations.
View Article and Find Full Text PDFThe Etoliko Lagoon in western Greece has experienced extensive human modification since the 20th century, both on the surrounding land and in the aquatic environment. To examine human impacts and disentangle climatic from anthropogenic changes, we present a suite of biomarker records that span the past two centuries (∼1790-2011). Specifically, we use terrigenous (n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and phytosterols) and aquatic (dinosterol, brassicasterol, cholesterol, and stigmasterol) biomarkers to document changes in nutrient inputs, combustion, and algal productivity.
View Article and Find Full Text PDFThe cathode materials in lithium-ion batteries (LIBs) require improvements to address issues such as surface degradation, short-circuiting, and the formation of dendrites. One such method for addressing these issues is using surface coatings. Coatings can be sought to improve the durability of cathode materials, but the characterization of the uniformity and stability of the coating is important to assess the performance and lifetime of these materials.
View Article and Find Full Text PDFThis work utilizes EIS to elucidate the impact of catalyst-ionomer interactions and cathode hydroxide ion transport resistance (,) on cell voltage and product selectivity for the electrochemical conversion of CO to ethylene. When using the same Cu catalyst and a Nafion ionomer, varying ink dispersion and electrode deposition methods results in a change of 2 orders of magnitude for , and ca. a 25% change in electrode porosity.
View Article and Find Full Text PDFStudies of the evolutionary causes and consequences of variation in circulating glucocorticoids (GCs) have begun to reveal how they are shaped by selection. Yet the extent to which variation in circulating hormones reflects variation in other important regulators of the hypothalamic-pituitary-adrenal (HPA) axis, and whether these relationships vary among populations inhabiting different environments, remain poorly studied. Here, we compare gene expression in the brain of female tree swallows (Tachycineta bicolor) from populations that breed in environments that differ in their unpredictability.
View Article and Find Full Text PDFMany populations of long-distance migrant shorebirds are declining rapidly. Since the 1970s, the lesser yellowlegs () has experienced a pronounced reduction in abundance of ~63%. The potential causes of the species' decline are complex and interrelated.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2021
The synthesis of microgels with pH-tunable swelling leads to adjustable and pH-responsive substrates for surface-enhanced Raman scattering (SERS)-active nanoparticles (NPs). Sterically stabilized and cross-linked latexes were synthesized from random copolymers of styrene (S) and 2-vinylpyridine (2VP). The pH-dependent latex-to-microgel transition and swellability were tuned based on their hydrophobic-to-hydrophilic content established by the S/2VP ratio.
View Article and Find Full Text PDFKubelka (Reports, 9 November 2018, p. 680) claim that climate change has disrupted patterns of nest predation in shorebirds. They report that predation rates have increased since the 1950s, especially in the Arctic.
View Article and Find Full Text PDFIntroduction: Significant event analysis (SEA) is well established in many primary care settings but can be poorly implemented. Reasons include the emotional impact on clinicians and limited knowledge of systems thinking in establishing why events happen and formulating improvements. To enhance SEA effectiveness, we developed and tested "guiding tools" based on human factors principles.
View Article and Find Full Text PDFBackground: Geolocators are useful for tracking movements of long-distance migrants, but potential negative effects on birds have not been well studied. We tested for effects of geolocators (0.8-2.
View Article and Find Full Text PDFObjectives: Hemophilia is a sex-linked condition affecting about 1 of every 5000 males in the United States. The management of children with hemophilia can be improved with regular intravenous infusion of factor VIII or IX, thus preventing crippling and sometimes fatal hemorrhage. Maintaining this vital intravenous access is often hampered by gradual loss of superficial veins or repeated central catheter sepsis and thrombosis.
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