195 research outputs found
Rate versus rhythm control and outcomes in patients with atrial fibrillation and chronic kidney disease: Data from the GUSTO-III Trial
Background: Atrial fi brillation (AF) and chronic kidney disease (CKD) have both beenshown to portend worse outcomes after acute myocardial infarction (MI); however, the benefi tof a rhythm control strategy in patients with CKD post-MI is unclear.Methods: We prospectively studied 985 patients with new-onset AF post-MI in theGUSTO-III trial, of whom 413 (42%) had CKD (creatinine clearance < 60 mL/min).A rhythm control strategy, defi ned as the use of an antiarrhythmic medication and/orelectrical cardioversion, was used in 346 (35%) of patients.Results: A rhythm control strategy was used in 34% of patients with CKD and 36% of patientswith no CKD. At hospital discharge, sinus rhythm was present in 487 (76%) of patients treatedwith a rate control strategy, vs. 276 (80%) in those treated with rhythm control (p = 0.20). CKDwas associated with a lower odds of sinus rhythm at discharge (unadjusted OR 0.56, 95% CI0.38–0.84, p < 0.001). However, in multivariable analyses, treatment with a rhythm controlstrategy was not associated with discharge rhythm (HR 1.068, 95% CI 0.69–1.66, p = 0.77),30-day mortality (HR 0.78, 95% CI 0.54–1.12, p = 0.18) or mortality from day 30 to 1 year(HR 1.00, 95% CI 0.59–1.69, p = 0.99). CKD status did not signifi cantly impact the relationshipbetween rhythm control and outcomes.Conclusions: Treatment with a rhythm or rate control strategy does not signifi cantly impactshort-term or long-term mortality in patients with post-MI AF, regardless of kidney disease status.Future studies to investigate the optimal management of AF in CKD patients are needed
Normal subgroups in the Cremona group (long version)
Let k be an algebraically closed field. We show that the Cremona group of all
birational transformations of the projective plane P^2 over k is not a simple
group. The strategy makes use of hyperbolic geometry, geometric group theory,
and algebraic geometry to produce elements in the Cremona group that generate
non trivial normal subgroups.Comment: With an appendix by Yves de Cornulier. Numerous but minors
corrections were made, regarding proofs, references and terminology. This
long version contains detailled proofs of several technical lemmas about
hyperbolic space
Microbial control of diatom bloom dynamics in the open ocean
Diatom blooms play a central role in supporting foodwebs and sequestering biogenic carbon to depth. Oceanic conditions set bloom initiation, whereas both environmental and ecological factors determine bloom magnitude and longevity. Our study reveals another fundamental determinant of bloom dynamics. A diatom spring bloom in offshore New Zealand waters was likely terminated by iron limitation, even though diatoms consumed <1/3 of the mixed-layer dissolved iron inventory. Thus, bloom duration and magnitude were primarily set by competition for dissolved iron between microbes and small phytoplankton versus diatoms. Significantly, such a microbial mode of control probably relies both upon out-competing diatoms for iron (i.e., K-strategy), and having high iron requirements (i.e., r-strategy). Such resource competition for iron has implications for carbon biogeochemistry, as, blooming diatoms fixed three-fold more carbon per unit iron than resident non-blooming microbes. Microbial sequestration of iron has major ramifications for determining the biogeochemical imprint of oceanic diatom blooms. Citation: Boyd, P. W., et al. (2012), Microbial control of diatom bloom dynamics in the open ocean, Geophys. Res. Lett., 39, L18601
Perspectives on Andean Prehistory and Protohistory: Papers from the Third Annual Northeast Conference on Andean Archaeology and Ethnohistory
This volume represents eight of the eighteen papers presented at the Third Northeast Conference on Andean Archaeology and Ethnohistory held at the University of Massachusetts, Amherst on October 27 and 28, 1984. It also includes a paper presented at the Second NCAAE held at the American Museum of Natural History on November 19-20, 1983. The papers include: Wandering Shellfish: New Insights from Southeastern Coastal Ecuador by Patricia Netherly, Late Prehistoric Terracing at Chijra in the Collca Valley, Peru: Preliminary Report I by Michael A. Malpass, The Topara Tradition: An Overview by Dwight T. Wallace, The Peruvian North Central Coast During the Early Intermediate Period: An Emerging Perspective by Richard E. Daggett, A Sequence of Monumental Architecture from Huamanchuco by John R. Topic, Duality in Public Architecture in the Upper Zena Valley by Patricia J. Netherly and Tom D. Dillehay, Piruru: A Preliminary Report on the Archaeological Botany of a Highland Andean Site by Lawrence Kaplan and Elisabeth Bonnier, Analysis of Organic Remains from Huamachuco Qollqas by Coreen E. Chiswell, Aspects of Casting Practice in Prehispanic Peru by Stuart V. Arnold, and Representations of the Cosmos: A Comparison of the Church of San Cristobal de Pampachiri with the Coricancha Drawing of Santacruz Pachacuti Yamqui Salcamaygua by Monica Barnes.https://digitalcommons.library.umaine.edu/andean_past_special/1000/thumbnail.jp
Using synchrotron-based X-ray absorption spectrometry to identify the arsenic chemical forms in mine waste materials
X-ray Absorption Near Edge Spectroscopy (XANES) gives arsenic form directly in the solid phase and has lower detection limits than extraction techniques. An important and common application of XANES is to use the shift of the edge position to determine the valence state. XANES speciation analysis is based on fitting linear combinations of known spectra from model compounds to determine the ratios of valence states and/or phases present. As(V)/As(III) ratios were determined for various Australian mine waste samples and dispersed mine waste samples from river/creek sediments in Vatukoula, Fiji. © 2007 American Institute of Physics
` Adding value to the fish! ´ Business Strategies in Fish Farming and Small-Scale Fishery
The development of values-based supply chains for fish and fish products from fisheries and aquaculture is a strategy to add value to the fish. This benefit refers to the double meaning of ‘value’; premium prices for high-value products and at the same time, the incorporation of environmental, social, cultural or ethical values based on a sustainable use of resources. Although small-scale fish production and fisheries have a long tradition in many regions of the European Union, fishermen and fish farmers face strong competition with industrialized fishery fleets as well as imports from lowcosts aquaculture. At the same time, European consumer surveys prove evidence that a consumers show an overaverage
Willingness to Pay (WTP) for fish produced locally and according to sustainability standards. With this paper,
we aim to identify and discuss fish farmers’ and fishermen’s strategies ensuring the viability of their businesses by adding value to their fish utilizing this so far often unused market potential. Four case studies serve as the basis for the analysis. The German case studies examined traditional carp pond farming in Franconia and recirculation aquaculture systems in northern Germany. The Italian case studies focus on saline aquaculture (marine and on-shore) in Tuscany
and mussel farming (inshore) in the Emilia-Romagna region. The English, Italian and Greek study cases analysed the situation of small-scale coastal fisheries in Cornwall, Tuscany and the Kavala region
Application of remote sensing to the study of the pelagic spiny lobster larval transport in the Tropical Atlantic
Deciphering the Chemical Basis of Nestmate Recognition
Social insects maintain colony cohesion by recognizing and, if necessary, discriminating against conspecifics that are not part of the colony. This recognition ability is encoded by a complex mixture of cuticular hydrocarbons (CHCs), although it is largely unclear how social insects interpret such a multifaceted signal. CHC profiles often contain several series of homologous hydrocarbons, possessing the same methyl branch position but differing in chain length (e.g., 15-methyl-pentatriacontane, 15-methyl-heptatriacontane, 15-methyl-nonatriacontane). Recent studies have revealed that within species these homologs can occur in correlated concentrations. In such cases, single compounds may convey the same information as the homologs. In this study, we used behavioral bioassays to explore how social insects perceive and interpret different hydrocarbons. We tested the aggressive response of Argentine ants, Linepithema humile, toward nest-mate CHC profiles that were augmented with one of eight synthetic hydrocarbons that differed in branch position, chain length, or both. We found that Argentine ants showed similar levels of aggression toward nest-mate CHC profiles augmented with compounds that had the same branch position but differed in chain length. Conversely, Argentine ants displayed different levels of aggression toward nest-mate CHC profiles augmented with compounds that had different branch positions but the same chain length. While this was true in almost all cases, one CHC we tested elicited a greater aggressive response than its homologs. Interestingly, this was the only compound that did not occur naturally in correlated concentrations with its homologs in CHC profiles. Combined, these data suggest that CHCs of a homologous series elicit the same aggressive response because they convey the same information, rather than Argentine ants being unable to discriminate between different homologs. This study contributes to our understanding of the chemical basis of nestmate recognition by showing that, similar to spoken language, the chemical language of social insects contains “synonyms,” chemicals that differ in structure, but not meaning
Multibeam bathymetric surveys of submarine volcanoes and mega-pockmarks on the Chatham Rise, New Zealand
Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Taylor & Francis for personal use, not for redistribution. The definitive version was published in New Zealand Journal of Geology and Geophysics 54 (2011): 329-339, doi:10.1080/00288306.2011.589860.Multibeam bathymetric surveys east of the South Island of New Zealand present images of submarine volcanoes and pockmarks west of Urry Knolls on the Chatham Rise, and evidence of submarine erosion on the southern margin of the Chatham Rise. Among numerous volcanic cones, diameters of the largest reach ~2000 m, and some stand as high as 400 m above the surrounding seafloor. The tops of most of the volcanic cones are flat, with hints of craters, and some with asymmetric shapes may show flank collapses. There are hints of both northeast-southwest and northwest-southeast alignments of volcanoes, but no associated faulting is apparent. Near and to the west of these volcanoes, huge pockmarks, some more than ~1 km in diameter, disrupt bottom topography. Pockmarks in this region seem to be confined to sea floor shallower than ~1200 m, but we see evidence of deeper pockmarks at water depths of up to 2100 m on profiles crossing the Bounty Trough. The pockmark field on the Chatham Rise seems to be bounded on the south by a trough near 1200 m depth; like others, we presume that contour currents have eroded the margin and created the trough.This research was supported by the National Science Foundation under grants EAR-0409564, EAR-0409609, and EAR-0409835.2012-08-3
PINCH1 Is Transcriptional Regulator in Podocytes That Interacts with WT1 and Represses Podocalyxin Expression
Background: PINCH1, an adaptor protein containing five LIM domains, plays an important role in regulating the integrin-mediated cell adhesion, migration and epithelial-mesenchymal transition. PINCH1 is induced in the fibrotic kidney after injury, and it primarily localizes at the sites of focal adhesion. Whether it can translocate to the nucleus and directly participate in gene regulation is completely unknown. Methodology/Principal Findings: Using cultured glomerular podocytes as a model system, we show that PINCH1 expression was induced by TGF-β1, a fibrogenic cytokine that promotes podocyte dysfunction. Interestingly, increased PINCH1 not only localized at the sites of focal adhesions, but also underwent nuclear translocation after TGF-β1 stimulation. This nuclear translocation of PINCH1 was apparently dependent on the putative nuclear export/localization signals (NES/NLS) at its C-terminus, as deletion or site-directed mutations abolished its nuclear shuttling. Co-immunoprecipitation and pull-down experiments revealed that PINCH1 interacted with Wilms tumor 1 protein (WT1), a nuclear transcription factor that is essential for regulating podocyte-specific gene expression in adult kidney. Interaction of PINCH1 and WT1 was mediated by the LIM1 domain of PINCH1 and C-terminal zinc-finger domain of WT1, which led to the suppression of the WT1-mediated podocalyxin expression in podocytes. PINCH1 also repressed podocalyxin gene transcription in a promoter-luciferase reporter assay. Conclusion/Significance: These results indicate that PINCH1 can shuttle into the nucleus from cytoplasm in podocytes, wherein it interacts with WT1 and suppresses podocyte-specific gene expression. Our studies reveal a previously unrecognized, novel function of PINCH1, in which it acts as a transcriptional regulator through controlling specific gene expression. © 2011 Wang et al
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