University of New Mexico

About: University of New Mexico is a education organization based out in Albuquerque, New Mexico, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 28870 authors who have published 64767 publications receiving 2578371 citations. The organization is also known as: UNM & Universitatis Novus Mexico.

Multitechnique Characterization of a Polyaniline–Iron–Carbon Oxygen Reduction Catalyst

Abstract: This paper summarizes a XANES, XPS, XRD, and Mo study of an oxygen reduction reaction (ORR) catalyst obtained via a heat treatment of polyaniline, iron, and carbon black. The catalyst was characterized at several critical synthesis stages and following heat treatment at various temperatures. The effect of sulfur during the synthesis was also investigated. XANES linear combination fitting (XANES-LCF) was used to determine the speciation of iron using 16 iron standards. The highest ORR activity was measured with a catalyst heat-treated at 900 °C, with the largest Fe−Nx content, as determined by the XANES-LCF, also characterized by the highest microporosity. An absence or a reduction in the amount of a sulfur-based oxidant in the aniline polymerization was found to lead to an increase in the amount of iron carbide formed during the heat treatment and a decrease in the number of Fe−N4 centers, thus attesting to an indirect beneficial role of sulfur in the catalyst synthesis. Using principal component analysis (PCA), a good correlation was found between the ORR activity and the presence of Fe−Nx structures.

Durability of PEFCs at High Humidity Conditions

Abstract: This work addresses issues of long-term durability of hydrogen-air polymer electrolyte fuel cells (PEFCs). The chromium in a Pt 3 Cr binary alloy catalyst has been found to migrate from cathode to anode during the course of life testing when operating within the oversaturated, or high-humidity, gas feed regime (one or both inlet feeds with a dew point equal to or higher than cell operating temperature) above 1 A/cm 2 current density. Other major factors such as membrane degradation, dissolution of catalyst-layer recast ionomer, catalyst oxidation, and catalyst agglomeration/growth have been identified as simultaneous, gradual processes that can lead to long-term PEFC failure. In situ cyclic voltammetry measurement of electrochemically active catalyst surface area shows a continuous decrease, revealing that catalyst agglomeration and/or growth may be a major cause of membrane electrode assembly degradation during middle-term life tests (i.e., operation times up to about 2000 h) under high-humidity conditions. Membrane and/or recast ionomer degradation was confirmed by the presence of fluoride and sulfate anions in the cathode outlet water. Scanning and transmission electron microscopy observation of a tested MEA suggest the loss of carbon-supported catalyst clusters and possible dissolution of recast Nafion ionomer.

Autophagy balances inflammation in innate immunity.

Abstract: Macroautophagy/autophagy is a homeostatic process with multiple effects on immunity. One of the pivotal contributions of autophagy in immunity is the cell autonomous control of inflammation. This property leads to systemic consequences and thereby influences the development of innate and adaptive immunity, which promotes or suppresses pathology in various disease contexts. In this review we focus on the intersections between autophagy and inflammasome activation, autophagy and interferons, and autophagy and inflammation in association with infection.

Genetic networks with canalyzing Boolean rules are always stable

Abstract: We determine stability and attractor properties of random Boolean genetic network models with canalyzing rules for a variety of architectures. For all power law, exponential, and flat in-degree distributions, we find that the networks are dynamically stable. Furthermore, for architectures with few inputs per node, the dynamics of the networks is close to critical. In addition, the fraction of genes that are active decreases with the number of inputs per node. These results are based upon investigating ensembles of networks using analytical methods. Also, for different in-degree distributions, the numbers of fixed points and cycles are calculated, with results intuitively consistent with stability analysis; fewer inputs per node implies more cycles, and vice versa. There are hints that genetic networks acquire broader degree distributions with evolution, and hence our results indicate that for single cells, the dynamics should become more stable with evolution. However, such an effect is very likely compensated for by multicellular dynamics, because one expects less stability when interactions among cells are included. We verify this by simulations of a simple model for interactions among cells.

Guidance on the emergent reversal of oral thrombin and factor Xa inhibitors.

Abstract: The new oral anticoagulants dabigatran, rivaroxaban and apixaban have advantages over warfarin which include no need for laboratory monitoring, less drug-drug interactions and less food-drug interactions. However, there is no established antidote for patients who are bleeding or require emergent surgery and there is a paucity of evidence to guide the clinical care during these situations. Members of thrombosis and anticoagulation groups participating in the Thrombosis and Hemostasis Summit of North America formulated expert opinion guidance for reversing the anticoagulant effect of the new oral anticoagulants and suggest: routine supportive care, activated charcoal if drug ingestion was within a couple of hours, and hemodialysis if feasible for dabigatran. Also, the pros and cons of the possible use of four factor prothrombin complex concentrate are discussed.