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Naphthenic Acids (NAs) are widely believed to universally act in a stabilizing capacity during the formation of water-in-crude oil emulsions. This work provides evidence to the contrary wherein differences between commercially acquired NAs and those extracted from crude exhibit opposing effects on emulsion stability. Addition of the commercial NAs to a crude oil prior to water-in-oil emulsion formation resulted in an increase in emulsion destabilization rate. This was demonstrated via quantification of water droplet coalescence using pulsed field gradient nuclear magnetic resonance (NMR) and, over long timescales in the visual observation of the disengagement of a free water phase. The efficacy of the commercial NAs to act in such a demulsification capacity was shown to be effective at concentrations as low as 0.5v/v% and in the presence of saline water of up to 3.5 wt% NaCl. Differences in NA demulsifying ability was observed between three crude oils of various origins with some demonstrating clear visual phase separation whilst others remained in an emulsified state. Conversely, addition of NAs extracted from a crude oil at similar concentrations had negligible effect on the rate of emulsion destabilization. Comparative characterization of the commercial and indigenous NAs was performed using 1H NMR, Diffusion Ordered Spectroscopy (DOSY), Rheometry, Pendant Drop Tensiometry, and Gas Chromatography–Mass Spectrometry. The results of this characterization indicated that differences in emulsion stability were governed not by differences in the reduction of emulsion droplet interfacial tension (IFT) but by the kinetics of molecular diffusion of the NAs during both the emulsification and destabilization phases. [ABSTRACT FROM AUTHOR]

Animals are strongly connected to the environments they live in and may become adapted to local environments. Examining genetic–environment associations of key indicator species, like seabirds, provides greater insights into the forces that drive evolution in marine systems. Here we examined a RADseq dataset of 19,213 SNPs for 99 rhinoceros auklets (Cerorhinca monocerata) from five western Pacific and 10 eastern Pacific breeding colonies. We used partial redundancy analyses to identify candidate adaptive loci and to quantify the effects of environmental variation on population genetic structure. We identified 262 candidate adaptive loci, which accounted for 3.0% of the observed genetic variation among western Pacific and eastern Pacific breeding colonies. Genetic variation was more strongly associated with pH and maximum current velocity, than maximum sea surface temperature. Genetic–environment associations explain genetic differences between western and eastern Pacific populations; however, genetic variation within the western and eastern Pacific Ocean populations appears to follow a pattern of isolation‐by‐distance. This study represents a first to quantify the relationship between environmental and genetic variation for this widely distributed marine species and provides greater insights into the evolutionary forces that act on marine species. [ABSTRACT FROM AUTHOR]

Tufted Puffins (Fratercula cirrhata) are experiencing population declines in some parts of their distribution, making this a species of increased conservation interest. Genetic data will help to identify Tufted Puffin populations of conservation importance and provide an important tool for developing conservation management plans. This species is broadly distributed across the North Pacific Ocean but little is known about the extent of genetic variation and differentiation across their range. In this study, we examine mitochondrial DNA (mtDNA), 8 microsatellite loci and 1,260 single nucleotide polymorphisms (SNPs) to determine the extent of gene flow among 7 breeding colonies (Oregon to the western Aleutians) in the North American breeding range of the species and identify potential barriers to dispersal. Our results show that most breeding colonies form a single genetic cluster, and mtDNA data show substantial historical gene flow among populations. For the microsatellite dataset, all FST comparisons that include St. Lazaria, in southeast Alaska, except Oregon, which had a small sample size, were significant as were comparisons between Triangle Island and the two westernmost sampling sites of Buldir and Aiktak. For the SNP dataset, FST comparisons were low and nonsignificant, further suggesting that breeding colonies form a single panmictic population. Individuals were more closely related to individuals from the same colony, and we found a weak relationship between genetic and geographic distance. This suggests that dispersal among colonies is high, likely facilitated by an overlap in wintering ranges among colonies. The high connectivity among breeding colonies indicates that Tufted Puffins form a single conservation unit, although future genetic studies should incorporate a whole genome sequencing approach to assessing how functional genetic diversity varies across their distribution. [ABSTRACT FROM AUTHOR]

Background: Hyperhemolysis syndrome (HHS) is a posttransfusion complication most frequently seen in sickle cell disease (SCD), characterized by rapid destruction of transfused and autologous red blood cells (RBCs), resulting in reticulocytopenia and a decrease in hemoglobin to below pretransfusion levels. Additional RBC transfusion can be life threatening. Most patients improve with intravenous immune globulin and steroids, but in refractory cases, hyperhemolysis may result in multiorgan failure and death in the absence of salvage therapy. The exact pathophysiology of HHS remains uncertain, yet new insights suggest that RBC destruction is driven by activated macrophages. Therefore, we propose that antimacrophage therapy may represent an effective treatment.Case Report: A case of life-threatening HHS, refractory to intravenous immune globulin and steroids, in a patient with SCD is presented. Marked elevation in ferritin, an indirect marker of macrophage activation, a negative direct antiglobulin test, and the absence of RBC alloantibodies was noted. A hemoglobin nadir of 2.1 g/dL and resultant hypoxemia-induced organ failure prompted the use of tocilizumab, an interleukin-6 receptor monoclonal antibody. Hemoglobin-based oxygen carrier-201, a cell-free polymerized bovine hemoglobin, was used to support the patient during critical anemia.Results: Hemolysis resolved and ferritin dramatically decreased after administration of tocilizumab, which was well tolerated. A full recovery was achieved.Conclusion: This case highlights both a novel and successful approach to managing refractory transfusion-induced hyperhemolysis with tocilizumab and provides further evidence supporting the role for macrophage activation in the destruction of RBCs in antibody-negative HHS. We propose that tocilizumab is an effective and rapid salvage therapy for refractory HHS. [ABSTRACT FROM AUTHOR]