Cross-Bedded Woody Debris From A Pliocene Forested River System In the High Arctic: Beaufort Formation, Meighen Island, Canada

Abstract: Cross-bedding, the inclined internal stratification that records the migration of certain transverse sedimentary bedforms, is nearly ubiquitous in current-transported bedload sediments. Although examples of the structure are known from inorganic clastic sediments and sedimentary rocks from practically all depositional environments and intervals of geologic history, here we report cross-bedded lenses that are composed wholly or significantly of woody debris, in Pliocene alluvium of the Beaufort Formation in the Canadian High Arctic. The uniqueness of cross-bedded woody debris has hitherto been overlooked, but we demonstrate that, in the entire Phanerozoic record, it is apparently restricted to alluvium deposited during a warm climatic interval that permitted the growth of boreal-type forests within 10° latitude of the North Pole. The marked spatiotemporal restriction of cross-bedded woody debris implies that there may be environmental factors, unique to polar forests, which promote the subaqueous transport of large amounts of fine woody debris as fluvial bedload. We propose a non-uniformitarian conceptual model for the formation of cross-bedded woody debris in forested polar rivers whereby an exceptional abundance of woody debris could accumulate, and become saturated and denser than water, due to reduced decomposition on forest floors that were subject to prolonged periods of darkness and subzero temperatures

Remote Predictive Mapping 5. Using a Lidar Derived DEM to Test the Influence of Variable Overburden Thickness and Bedrock on Drainage and Basin Morphology

A 4–m lidar digital elevation model (DEM) provides sufficient resolution to examine the impact of variable till cover on the incision history of multiple small (5 km2) catchments in eastern Canada.  The study site was selected because it has homogeneous bedrock geology that dips parallel to the land surface, is tectonically stable, has undergone common base level changes, and has a common ice history, with variable overburden thickness, from thin cover in the west to thick cover in the east. Basin morphometrics were compared for similar-size basins that have variable till cover thicknesses. Basins with thicker till cover are wider and show differences in hypsometries compared to those where till cover is thin. Two basins representing end members of till thickness were measured for stream discharge and water chemistry. Thick till  (> 1 m) on the eastern half of North Mountain retards infiltration sufficiently to promote overland flow and accelerate incision relative to areas with thinner till.  Till thickness and continuity therefore are expected to impede the achievement of steadiness and may also delay stream power law relationships in larger catchments until till cover has been effectively eroded.SOMMAIREUn modèle altimétrique numérique (MAN) par lidar 4 m offre une résolution suffisante pour étudier l'impact des divers dépôts de till sur l'histoire de l'érosion linéaire de multiples petits (5 km2) bassins versants dans l'Est du Canada.  Le site d'étude a été choisi parce que sa géologie est homogène et que son pendage est parallèle à la surface du sol, qu’il est tectoniquement stable, qu’il a subi des changements similaires du niveau de base d’érosion, de même qu’ une histoire glaciaire similaire, avec une épaisseur de mort-terrain variable, d’une couverture mince à l'ouest jusqu'à une couverture épaisse à l'est. La morphométrie du bassin a été comparée à celle de bassins de taille semblable aux épaisseurs de till variables.  Les bassins aux couvertures de till plus épaisses sont plus larges et montrent des différences hypsométriques comparé  à ceux aux couvertures minces.  Deux bassins représentant les termes extrêmes de l'épaisseur du till ont été mesurées quant au débit du courant et à la chimie de l'eau.  Les till épais (>1 m) sur la moitié est du mont Nord retardent l'infiltration, ce qui favorise l'écoulement en surface et accélèrent l’érosion linéaire par rapport aux zones couvertes de couches de till plus minces.  On s’attend donc à ce que l'épaisseur de la couche de till et sa continuité agissent comme une entrave à la stabilité et puissent aussi retarder les effets de la loi de puissance de l’écoulement dans les grands bassins récepteurs jusqu'à ce que la couverture de till a été effectivement érodée

PoLAR-FIT: Pliocene Landscapes and Arctic Remains—Frozen in Time

This short summary presents selected results of an ongoing investigation into the feedbacks that contribute to amplified Arctic warming. The consequences of warming for Arctic biodiversity and landscape response to global warmth are currently being interpreted. Arctic North American records of large-scale landscape and paleoenvironmental change during the Pliocene are exquisitely preserved and locked in permafrost, providing an opportunity for paleoenvironmental and faunal reconstruction with unprecedented quality and resolution. During a period of mean global temperatures only ~2.5°C above modern, the Pliocene molecular, isotopic, tree-ring, paleofaunal, and paleofloral records indicate that the high Arctic mean annual temperature was 11°C–19°C above modern values, pointing to a much shallower latitudinal temperature gradient than exists today. It appears that the intense Neogene warming caused thawing and weathering to liberate sediment and create a continuous and thick (>2.5 km in places) clastic wedge from at least Banks Island to Meighen Island to form a coastal plain that provided a highway for camels and other mammals to migrate and evolve in the high Arctic. In this summary we highlight the opportunities that exist for research on these and related topics with the PoLAR-FIT community.RÉSUMÉCe bref résumé présente les résultats choisis d'une enquête en cours sur les déclencheurs qui contribuent à l’amplification du réchauffement de l'Arctique. Les conséquences du réchauffement sur la biodiversité arctique et de la réponse du paysage au réchauffement climatique sont en cours d’être interprété. Des dossiers nord-américains de paysage à grande échelle et le changement paléoenvironnementales durant le Pliocène sont exceptionnellement préservés et scellées dans un état de congélation qui fournissant une occasion pour la reconstruction paléoenvironnementale et faunistique avec une qualité et une résolution sans précédent. Pendent une période de réchauffement global seulement ~2,5°C au-dessus de moderne les dossiers, moléculaire, isotopique, annaux de croissance, paléofaunistique et paléovégétation indiquent que l'Arctique a connu une augmentation de la température annuelle moyenne de 11°C–19°C au-dessus de moderne, en montrant un inferieur gradient de température latitudinal qu'aujourd'hui. Il semble que le réchauffement intense pendent le Néogène a provoqué la décongélation et erosion pour libérer les sédiments et créer une plaine côtière continuel et épaisse (> 2,5 km dans lieux) qui a fourni une route pour les chameaux et autres mammifères pour migrer et évoluer dans l’Haut-Arctique. Dans ce résumé, nous soulignons les opportunités qui existent pour la recherche sur ces sujets et les sujets connexes avec la communauté PoLAR-FIT

Evidence for fire in the pliocene arctic in response to amplified temperature

The mid-Pliocene is a valuable time interval for investigating equilibrium climate at current atmospheric CO2 concentrations because atmospheric CO2 concentrations are thought to have been compara

Genome analysis and physiological comparison of Alicycliphilus denitrificans strains BC and K601T

The genomes of the Betaproteobacteria Alicycliphilus denitrificans strains BC and K601T have been sequenced to get insight into the physiology of the two strains. Strain BC degrades benzene with chlorate as electron acceptor. The cyclohexanol-degrading denitrifying strain K601T is not able to use chlorate as electron acceptor, while strain BC cannot degrade cyclohexanol. The 16S rRNA sequences of strains BC and K601T are identical and the fatty acid methyl ester patterns of the strains are similar. Basic Local Alignment Search Tool (BLAST) analysis of predicted open reading frames of both strains showed most hits with Acidovorax sp. JS42, a bacterium that degrades nitro-aromatics. The genomes include strain-specific plasmids (pAlide201 in strain K601T and pAlide01 and pAlide02 in strain BC). Key genes of chlorate reduction in strain BC were located on a 120 kb megaplasmid (pAlide01), which was absent in strain K601T. Genes involved in cyclohexanol degradation were only found in strain K601T. Benzene and toluene are degraded via oxygenase-mediated pathways in both strains. Genes involved in the meta-cleavage pathway of catechol are present in the genomes of both strains. Strain BC also contains all genes of the ortho-cleavage pathway. The large number of mono- and dioxygenase genes in the genomes suggests that the two strains have a broader substrate range than known thus far.This research was supported by the Technology Foundation, the Applied Science Division (STW) of the Netherlands Organization for Scientific Research (NWO), project number 08053, the graduate school WIMEK (Wageningen Institute for Environment and Climate Research, which is part of SENSE Research School for Socio-Economic and Natural Sciences of the Environment, www.wimek-new.wur.nl and www.sense.nl), SKB (Dutch Centre for Soil Quality Management and Knowledge Transfer, www.skbodem.nl) and the Consolider project CSD-2007-00055. The research was incorporated in the TRIAS (TRIpartite Approaches 469 toward Soil systems processes) program (http://www.nwo.nl/en/research-and-results/programmes/alw/trias-tripartite-approach-to-soil-system-processes/index. html). Flávia Talarico Saia was supported by a FAPESP (the State of São Paulo Research Foundation) scholarship (2006-01997/5). The work conducted by the DOE JGI is supported by the Office of Science of the United States Department of Energy under contract number DE-AC02-05CH11231. Alfons Stams acknowledges support by an ERC (European Research Counsil) advanced grant (project 323009). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Effect of aliskiren on post-discharge outcomes among diabetic and non-diabetic patients hospitalized for heart failure: insights from the ASTRONAUT trial

Aims The objective of the Aliskiren Trial on Acute Heart Failure Outcomes (ASTRONAUT) was to determine whether aliskiren, a direct renin inhibitor, would improve post-discharge outcomes in patients with hospitalization for heart failure (HHF) with reduced ejection fraction. Pre-specified subgroup analyses suggested potential heterogeneity in post-discharge outcomes with aliskiren in patients with and without baseline diabetes mellitus (DM). Methods and results ASTRONAUT included 953 patients without DM (aliskiren 489; placebo 464) and 662 patients with DM (aliskiren 319; placebo 343) (as reported by study investigators). Study endpoints included the first occurrence of cardiovascular death or HHF within 6 and 12 months, all-cause death within 6 and 12 months, and change from baseline in N-terminal pro-B-type natriuretic peptide (NT-proBNP) at 1, 6, and 12 months. Data regarding risk of hyperkalaemia, renal impairment, and hypotension, and changes in additional serum biomarkers were collected. The effect of aliskiren on cardiovascular death or HHF within 6 months (primary endpoint) did not significantly differ by baseline DM status (P = 0.08 for interaction), but reached statistical significance at 12 months (non-DM: HR: 0.80, 95% CI: 0.64-0.99; DM: HR: 1.16, 95% CI: 0.91-1.47; P = 0.03 for interaction). Risk of 12-month all-cause death with aliskiren significantly differed by the presence of baseline DM (non-DM: HR: 0.69, 95% CI: 0.50-0.94; DM: HR: 1.64, 95% CI: 1.15-2.33; P < 0.01 for interaction). Among non-diabetics, aliskiren significantly reduced NT-proBNP through 6 months and plasma troponin I and aldosterone through 12 months, as compared to placebo. Among diabetic patients, aliskiren reduced plasma troponin I and aldosterone relative to placebo through 1 month only. There was a trend towards differing risk of post-baseline potassium ≥6 mmol/L with aliskiren by underlying DM status (non-DM: HR: 1.17, 95% CI: 0.71-1.93; DM: HR: 2.39, 95% CI: 1.30-4.42; P = 0.07 for interaction). Conclusion This pre-specified subgroup analysis from the ASTRONAUT trial generates the hypothesis that the addition of aliskiren to standard HHF therapy in non-diabetic patients is generally well-tolerated and improves post-discharge outcomes and biomarker profiles. In contrast, diabetic patients receiving aliskiren appear to have worse post-discharge outcomes. Future prospective investigations are needed to confirm potential benefits of renin inhibition in a large cohort of HHF patients without D

Relatório de estágio em farmácia comunitária

Relatório de estágio realizado no âmbito do Mestrado Integrado em Ciências Farmacêuticas, apresentado à Faculdade de Farmácia da Universidade de Coimbr

Surficial geology of the Standish quadrangle, Maine

Maine Geological Survey, Open-File Map 99-101https://digitalmaine.com/mgs_maps/2000/thumbnail.jp

Surficial geology of the Standish 7.5-minute quadrangle, York and Cumberland Counties, Maine

Maine Geological Survey, Open-File Report 99-132https://digitalmaine.com/mgs_publications/1237/thumbnail.jp