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To understand the marine feeding ecology of Arctic lamprey (Lethenteron camtschaticum) in the eastern Bering Sea, visual observations and DNA metabarcoding of gut contents (N = 250) were used to characterize Arctic lamprey diet composition in 2014 and 2015. Differences among individual diets were evaluated by collection year, capture site, and fish size. Hard structures and tissues were observed during visual examinations of gut contents, and 10 ray-finned fish taxa were identified by DNA metabarcoding. The most frequently observed taxa included capelin (Mallotus villosus), Pacific herring (Clupea pallasii), Pacific sand lance (Ammodytes hexapterus), and gadids. Six taxa were reported for the first time as prey for Arctic lamprey. Individual diets differed between collection years, among capture sites, and among size classes; however, both collection year and size class explained only a small portion of diet variability ([R.sup.2] = 0.01 and 0.04, respectively) relative to capture site ([R.sup.2] = 0.49). These study results indicate that Arctic lamprey is a flesh-feeding species and highlight the value of DNA metabarcoding to characterize the diet of a poorly understood lamprey species. Pour comprendre l'ecologie de l'alimentation en mer des lamproies arctiques (Lethenteron camtschaticum) dans la mer de Behring orientale, des observations visuelles et des metacodes-barres d'ADN de contenus stomacaux (N = 250) ont ete utilises pour caracteriser la composition des regimes alimentaires de lamproies arctiques en 2014 et 2015. Les differences de regimes alimentaires entre individus ont ete evaluees en fonction de l'annee de prelevement, du site de capture et de la taille des poissons. Des structures dures et des tissus ont ete observes durant les examens visuels de contenus stomacaux, et 10 taxons de poissons a nageoires a rayons ont ete identifies grace aux metacodes-barres d'ADN. Parmi les taxons les plus frequents figuraient le capelan (Mallotus villosus), le hareng du Pacifique (Clupea pallasii), le lancon gourdeau (Ammodytes hexapterus) et des gadides. Six taxons sont signales pour la premiere fois comme proies de lamproies arctiques. Les regimes alimentaires individuels varient d'une annee de prelevement a l'autre, au sein des sites de capture et au sein des classes de taille; cependant, l'annee de prelevement et la taille n'expliquent qu'une petite partie de la variabilite des regimes alimentaires ([R.sup.2] = 0,01 et 0,04, respectivement) comparativement au site ([R.sup.2] = 0,49). Ces resultats indiquent que la lamproie arctique est une espece mangeuse de chair et soulignent la valeur des metacodes-barres d'ADN pour caracteriser le regime alimentaire d'une espece de lamproies mal comprise. [Traduit par la Redaction], Introduction Characterizing the diets of marine-phase lamprey poses a special challenge to researchers. Diet analysis of fishes has largely relied upon morphological identification of prey remains and (or) undigested hard [...]

Plasmodium vivax is the most widely distributed malaria parasite that infects humans.sup.1. P. vivax invades reticulocytes exclusively, and successful entry depends on specific interactions between the P. vivax reticulocyte-binding protein 2b (PvRBP2b) and transferrin receptor 1 (TfR1).sup.2. TfR1-deficient erythroid cells are refractory to invasion by P. vivax, and anti-PvRBP2b monoclonal antibodies inhibit reticulocyte binding and block P. vivax invasion in field isolates.sup.2. Here we report a high-resolution cryo-electron microscopy structure of a ternary complex of PvRBP2b bound to human TfR1 and transferrin, at 3.7 Å resolution. Mutational analyses show that PvRBP2b residues involved in complex formation are conserved; this suggests that antigens could be designed that act across P. vivax strains. Functional analyses of TfR1 highlight how P. vivax hijacks TfR1, an essential housekeeping protein, by binding to sites that govern host specificity, without affecting its cellular function of transporting iron. Crystal and solution structures of PvRBP2b in complex with antibody fragments characterize the inhibitory epitopes. Our results establish a structural framework for understanding how P. vivax reticulocyte-binding protein engages its receptor and the molecular mechanism of inhibitory monoclonal antibodies, providing important information for the design of novel vaccine candidates. Structural studies show that conserved residues in Plasmodium vivax reticulocyte-binding protein 2b determine interactions with transferrin receptor 1 that are essential for host invasion, suggesting avenues for designing vaccines that work across P. vivax strains., Author(s): Jakub Gruszczyk [sup.1] , Rick K. Huang [sup.2] , Li-Jin Chan [sup.1] [sup.3] , Sébastien Menant [sup.1] , Chuan Hong [sup.2] , James M. Murphy [sup.1] [sup.3] , Yee-Foong [...]

Although necrosis and necroinflammation are central features of many liver diseases, the role of programmed necrosis in the context of inflammation-dependent hepatocellular death remains to be fully determined. Here, we have demonstrated that the pseudokinase mixed lineage kinase domain-like protein (MLKL), which plays a key role in the execution of receptor-interacting protein (RIP) kinase-dependent necroptosis, is upregulated and activated in human autoimmune hepatitis and in a murine model of inflammation-dependent hepatitis. Using genetic and pharmacologic approaches, we determined that hepatocellular necrosis in experimental hepatitis is driven by an MLKL-dependent pathway that occurs independently of RIPK3. Moreover, we have provided evidence that the cytotoxic activity of the proinflammatory cytokine IFN-γ in hepatic inflammation is strongly connected to induction of MLKL expression via activation of the transcription factor STAT1. In summary, our results reveal a pathway for MLKL-dependent programmed necrosis that is executed in the absence of RIPK3 and potentially drives the pathogenesis of severe liver diseases., Introduction Although the liver is an organ of remarkable regenerative capacity, cell death-related compensatory tissue injury responses commonly culminate in fibrosis and eventually cirrhosis, a major cause of morbidity worldwide. [...]

The Par-1/MARK protein kinases play a pivotal role in establishing cellular polarity. This family of kinases contains a unique domain architecture, in which a ubiquitin-associated (UBA) domain is located C-terminal to the kinase domain. We have used a combination of x-ray crystallography and NMR dynamics experiments to understand the interaction of the human (h) MARK3 UBA domain with the adjacent kinase domain as compared with ubiquitin. The x-ray crystal structure of the linked hMARK3 kinase and UBA domains establishes that the UBA domain forms a stable intramolecular interaction with the N-terminal lobe of the kinase domain. However, solution-state NMR studies of the isolated UBA domain indicate that it is highly dynamic, undergoing conformational transitions that can be explained by a folding-unfolding equilibrium. NMR titration experiments indicated that the hMARK3 UBA domain has a detectable but extremely weak affinity for monoubiquitin, which suggests that conformational instability of the isolated hMARK3 UBA domain attenuates binding to ubiquitin despite the presence of residues typically involved in ubiquitin recognition. Our data identify a molecular mechanism through which the hMARK3 UBA domain has evolved to bind the kinase domain, in a fashion that stabilizes an open conformation of the N-and C-terminal lobes, at the expense of its capacity to engage ubiquitin. These results may be relevant more generally to the 30% of UBA domains that lack significant ubiquitin-binding activity, and they suggest a unique mechanism by which interaction domains may evolve new binding properties. catalytic domain | dynamics | Par-1 | relaxation | ubiquitin-associated

Abstract--We tested the hypothesis that larger juvenile sockeye salmon (Oncorhynchus nerka) in Bristol Bay, Alaska, have higher marine-stage survival rates than smaller juvenile salmon. We used scales from returning adults [...]

Author(s): James M. Murphy (corresponding author) [1]; David M. H. Sexton [1]; David N. Barnett [1]; Gareth S. Jones [1]; Mark J. Webb [1]; Matthew Collins [1]; David A. Stainforth [...]

Research has been conducted on the receptor systems for the hemopoietic cytokines GM-CSF, IL-3, and IL-5 consisting of the ligand-specific alpha receptor subunits which activate the shared beta(c) subunit. The structure of the complete beta(c) extracellular domain has been investigated and the results are reported.

A finite-element model of a hard disk drive (HDD) is developed to investigate the response of a HDD to linear and rotary shock impulses. The simulations are performed for both operational and nonoperational HDD models. The operational HDD model uses linear springs to represent the air bearing stiffness of the head-disk interface. The nonoperational HDD model has the magnetic head in the docked position at the inner diameter of the disk. The geometry is developed using a three-dimensional computer aided design (CAD) package and is then imported into a preprocessor. The transient solution is performed using a commercially available finite-element solver. Index Terms--Finite elements, hard disk drive (HDD), head disk interface, head slap, shock response.

Larry J. Sabato THE KENNEDY HALF CENTURY The presidency, assassination, and lasting legacy of John F. Kennedy 427pp. Bloomsbury. 19.99 [pounds sterling] (US $30). 978 1 62040 280 1 Philip [...]

Pacific sardines, Sardinops sagax (Jenyns, 1842), are an important forage and commercial species off central and southern California. From the late 1920s through the early 1940s, sardines were a major [...]

David Talbot THE DEVIL'S CHESSBOARD Allen Dulles, the CIA, and the rise of America's secret government 620pp. Harper Collins. 25 [pounds sterling] (US $29.99). 978 0 06 227616 2 Given [...]

Robert A. Caro THE YEARS OF LYNDON JOHNSON Volume Four: The Passage of Power 712pp. Bodley Head. 35 [pounds sterling]. 978 1 847 92217 5 US: Knopf. $35.978 0 679 [...]

Christopher Turner ADVENTURES IN THE ORGASMATRON Wilhelm Reich and the invention of sex 446pp. Fourth Estate. 25 [pounds sterling]. 978 0 00 718157 5 US: Farrar, Straus and Giroux. $35. [...]

Michael Burleigh SMALL WARS, FAR AWAY PLACED The genesis of the modern world: 1945-65 588pp. Macmillan. 25 [pounds sterling]. 978 0 230 75232 0 Michael Burleigh's earlier works, Blood and [...]

Charles McCarry THE SECRET LOVERS 320pp. 978 0 7156 4502 4 SECOND SIGHT 464pp. 978 0 7156 4505 5 THE OLD BOYS 512pp. 978 0 7156 4303 7 Paperback, 7.99 [...]

John Sbardellati J. EDGAR HOOVER GOES TO THE MOVIES The FBI and the origins of Hollywood's Cold War 264pp. Cornell University Press. $27.95; distributed in the UK by NBN. 17.50 [...]

Stone, I. F. American Radical: The Life and Times of I. F. Stone. D. D. Guttenplan. New York: Farrar, Straus & Giroux, 2009. 592 pp. $35.00. 'Guttenplan has given us [...]

Kissinger, Henry The Flawed Architect: Henry Kissinger and American Foreign Policy. Jussi Hanhimaki. Oxford: Oxford UP, 2005. 492 pp. $35.00. The author's 'extensive use of original sources will give this […]