Glacier Physics of the Puget Lobe, Southwest Cordilleran Ice Sheet

The Puget lobe, the southwest-most extension of the Cordilleran ice sheet, provides an excellent opportunity to examine the connection between glacier physics and the resulting products of glaciation. The action of water, at and within the sediments of the glacier bed, is particularly significant for the geologic record of this ice sheet. Physical data and inferred mass balance relationships constrain lobe reconstruction and predict sliding velocities in excess of 500 m/a and water discharges of nearly 1 * 10" m3/a. This sub-glacial water produced a dendritic channel pattern well predicted by static analysis of sub-glacial hydrology. Near to the eastern ice margin, a much larger single channel drained subglacially and episodically, with tributary ice-dammed lakes releasing their water as jokulhlaups. Basal meltwater generated near-hydrostatic water pressures and very low till strengths at the base of the ice sheet. Water pressure dropped only close to the ice margin, allowing normal stresses to rise to significant fractions of the total ice overburden. Thus marginal and interior zones impose contrasting bed conditions. Although observation of sub-glacial deposits will reflect the late-stage passage of the marginal zone, conditions within the ice-sheet interior, far more significant to glacier history and behavior, may be substantially different.Le lobe de Puget, à la limite sud-ouest de l'Inlandsis de la Cordillère, permet d'étudier les liens entre la physique glaciaire et l'action glaciaire. L'action de l'eau à proximité et à l'intérieur des sédiments du lit glaciaire est un aspect particulièrement important de la géologie de l'inlandsis. Les données d'ordre physique et les calculs du bilan de masse permettent de faire une reconstitution assez fidèle du lobe et d'extrapoler les vitesses de glissement au delà de 500 m/a et les débits d'eau de près de 1 * 10" m3/a. L'écoulement de l'eau sous-glaciaire a créé un réseau de chenaux dentritiques que l'analyse statique de l'hydrologie sous-glaciaire a extrapolé avec justesse. Près de la marge glaciaire orientale, un important chenal isolé a assuré épisodiquement le drainage sous-glaciaire, alors que les lacs de barrage glaciaire emprisonnés dans les vallées adjacentes se déchargeaient par débâcles. L'eau de fonte basale a produit des pressions d'eau près de l'équilibre hydrostatique et de très faibles résistances du till à la base de l'inlandsis. La pression de l'eau ne diminuait que près de la marge glaciaire, laissant ainsi les taux de contrainte normaux s'élever jusqu'à des proportions importantes de la couverture totale de glace. Ainsi les conditions du lit sont très différentes selon qu'il se situe en zone interne ou en zone marginale. L'observation des dépôts sous-glaciaires révèle la phase finale en zone marginale, mais les conditions à l'intérieur même de l'inlandsis, d'une plus grande portée quant à l'évolution et au comportement du glacier, pourraient être très différentes.Der Puget-Lappen, die sûdwestliche Ausdehnung der Kordilleren-Eisdecke, bietet eine ausgezeichnete Gelegenheit, die Beziehung zwischen glazialer Physik und den daraus resultierenden Produkten der Vereisung zu untersuchen. Die Wirkung von Wasser in der Nàhe der Sedimente des Gletscherbettes und in ihnen ist besonders signifikant fur die geologische Dokumentierung der Eisdecke. Physikalische Daten und abgeleitete Massenbilanz-Beziehungen erlauben eine getreue Rekonstruktion des Lappens und Voraussagen ùber Rutschgeschwindigkeiten von ùber 500 m/a und Wasserfùhrungen von nahezu 1 * 1011 m3/a zu machen. Dies subglaziale Wasser bewirkte ein baumartiges Kanal-Muster, welches die statische Analyse der subglazialen Hydrologie richtig vorausgesagt hatte. In der Nàhe des ôstlichen Eisrands bewirkte ein sehr viel breiterer einzelner Kanal gelegentlich eine subglaziale Drânage, und tributàre, durch Eis eingeschlossene Seen entlieBen ihr Wasser in Gletscherlâufen. Basales Schmelzwasser bewirkte fast hydrostatische Wasserdruckwerte und sehr niedrige Widerstànde des Tills an der Basis der Eisdecke. Der Wasserdruck sank nur in der Nàhe des Eisrands, so daB normaler Druck bis zu bedeutenden Proportionen der totalen Eislast anstieg. So sind die bedingungen des Bettes sehr verschieden, je nachdem ob es sich in der Randzone oder der inneren Zone bef indet. Obgleich die Beobachtung der subglazialen Ablagerungen die Endphase der Randzone spiegelt, kônnten doch die Bedingungen im Innern der Eisdecke, die fur die Geschichte und das Verhalten des Gletschers viel wich-tiger sind, sehr verschieden sein

Bapineuzumab for mild to moderate Alzheimer’s disease in two global, randomized, phase 3 trials

Background Our objective was to evaluate the efficacy (clinical and biomarker) and safety of intravenous bapineuzumab in patients with mild to moderate Alzheimer’s disease (AD). Methods Two of four phase 3, multicenter, randomized, double-blind, placebo-controlled, 18-month trials were conducted globally: one in apolipoprotein E ε4 carriers and another in noncarriers. Patients received bapineuzumab 0.5 mg/kg (both trials) or 1.0 mg/kg (noncarrier trial) or placebo every 13 weeks. Coprimary endpoints were change from baseline to week 78 on the 11-item Alzheimer’s Disease Assessment Scale–Cognitive subscale and the Disability Assessment for Dementia. Results A total of 683 and 329 patients completed the current carrier and noncarrier trials, respectively, which were terminated prematurely owing to lack of efficacy in the two other phase 3 trials of bapineuzumab in AD. The current trials showed no significant difference between bapineuzumab and placebo for the coprimary endpoints and no effect of bapineuzumab on amyloid load or cerebrospinal fluid phosphorylated tau. (Both measures were stable over time in the placebo group.) Amyloid-related imaging abnormalities with edema or effusion were confirmed as the most notable adverse event. Conclusions These phase 3 global trials confirmed lack of efficacy of bapineuzumab at tested doses on clinical endpoints in patients with mild to moderate AD. Some differences in the biomarker results were seen compared with the other phase 3 bapineuzumab trials. No unexpected adverse events were observed. Trial registration Noncarriers (3000) ClinicalTrials.gov identifier NCT00667810; registered 24 Apr 2008. Carriers (3001) ClinicalTrials.gov identifier NCT00676143; registered 2 May 2008

Community-powered urban stream restoration: A vision for sustainable and resilient urban ecosystems

Urban streams can provide amenities to people living in cities, but those benefits are reduced when streams become degraded, potentially even causing harm (disease, toxic compounds, etc.). Governments and institutions invest resources to improve the values and services provided by urban streams; however, the conception, development, and implementation of such projects may not include meaningful involvement of community members and other stakeholders. Consequently, project objectives may be misaligned with community desires and needs, and projects may fail to achieve their goals. In February 2020, the 5(th) Symposium on Urbanization and Stream Ecology, an interdisciplinary meeting held every 3 to 5 y, met in Austin, Texas, USA, to explore new approaches to urban stream projects, including ways to maximize the full range of potential benefits by better integrating community members into project identification and decision making. The symposium included in-depth discussion about 4 nearby field case studies, participation of multidisciplinary urban stream experts from 5 continents, and input from the Austin community. Institutional barriers to community inclusion were identified and analyzed using real-world examples, both from the case studies and from the literature, which clarified disparities in power, equity, and values. Outcomes of the symposium have been aggregated into a vision that challenges the present institutional approach to urban stream management and a set of strategies to systematically address these barriers to improve restoration solutions. Integrating community members and other stakeholders throughout the urban restoration process, and a transparent decision-making process to resolve divergent objectives, can help identify appropriate goals for realizing both the ecological and social benefits of stream restoration

LSST: from Science Drivers to Reference Design and Anticipated Data Products

(Abridged) We describe here the most ambitious survey currently planned in the optical, the Large Synoptic Survey Telescope (LSST). A vast array of science will be enabled by a single wide-deep-fast sky survey, and LSST will have unique survey capability in the faint time domain. The LSST design is driven by four main science themes: probing dark energy and dark matter, taking an inventory of the Solar System, exploring the transient optical sky, and mapping the Milky Way. LSST will be a wide-field ground-based system sited at Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m effective) primary mirror, a 9.6 deg$^2$ field of view, and a 3.2 Gigapixel camera. The standard observing sequence will consist of pairs of 15-second exposures in a given field, with two such visits in each pointing in a given night. With these repeats, the LSST system is capable of imaging about 10,000 square degrees of sky in a single filter in three nights. The typical 5$\sigma$ point-source depth in a single visit in $r$ will be $\sim 24.5$ (AB). The project is in the construction phase and will begin regular survey operations by 2022. The survey area will be contained within 30,000 deg$^2$ with $\delta<+34.5^\circ$, and will be imaged multiple times in six bands, $ugrizy$, covering the wavelength range 320--1050 nm. About 90\% of the observing time will be devoted to a deep-wide-fast survey mode which will uniformly observe a 18,000 deg$^2$ region about 800 times (summed over all six bands) during the anticipated 10 years of operations, and yield a coadded map to $r\sim27.5$. The remaining 10\% of the observing time will be allocated to projects such as a Very Deep and Fast time domain survey. The goal is to make LSST data products, including a relational database of about 32 trillion observations of 40 billion objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures available from https://www.lsst.org/overvie

Ultra-High Resolution 3D Imaging of Whole Cells.

Fluorescence nanoscopy, or super-resolution microscopy, has become an important tool in cell biological research. However, because of its usually inferior resolution in the depth direction (50-80 nm) and rapidly deteriorating resolution in thick samples, its practical biological application has been effectively limited to two dimensions and thin samples. Here, we present the development of whole-cell 4Pi single-molecule switching nanoscopy (W-4PiSMSN), an optical nanoscope that allows imaging of three-dimensional (3D) structures at 10- to 20-nm resolution throughout entire mammalian cells. We demonstrate the wide applicability of W-4PiSMSN across diverse research fields by imaging complex molecular architectures ranging from bacteriophages to nuclear pores, cilia, and synaptonemal complexes in large 3D cellular volumes

The efficacy and safety of prokinetic agents in critically ill patients receiving enteral nutrition: a systematic review and meta-analysis of randomized trials.

BACKGROUND: Intolerance to enteral nutrition is common in critically ill adults, and may result in significant morbidity including ileus, abdominal distension, vomiting and potential aspiration events. Prokinetic agents are prescribed to improve gastric emptying. However, the efficacy and safety of these agents in critically ill patients is not well-defined. Therefore, we conducted a systematic review and meta-analysis to determine the efficacy and safety of prokinetic agents in critically ill patients. METHODS: We searched MEDLINE, EMBASE, and Cochrane Library from inception up to January 2016. Eligible studies included randomized controlled trials (RCTs) of critically ill adults assigned to receive a prokinetic agent or placebo, and that reported relevant clinical outcomes. Two independent reviewers screened potentially eligible articles, selected eligible studies, and abstracted pertinent data. We calculated pooled relative risk (RR) for dichotomous outcomes and mean difference for continuous outcomes, with the corresponding 95 % confidence interval (CI). We assessed risk of bias using Cochrane risk of bias tool, and the quality of evidence using grading of recommendations assessment, development, and evaluation (GRADE) methodology. RESULTS: Thirteen RCTs (enrolling 1341 patients) met our inclusion criteria. Prokinetic agents significantly reduced feeding intolerance (RR 0.73, 95 % CI 0.55, 0.97; P = 0.03; moderate certainty), which translated to 17.3 % (95 % CI 5, 26.8 %) absolute reduction in feeding intolerance. Prokinetics also reduced the risk of developing high gastric residual volumes (RR 0.69; 95 % CI 0.52, 0.91; P = 0.009; moderate quality) and increased the success of post-pyloric feeding tube placement (RR 1.60, 95 % CI 1.17, 2.21; P = 0.004; moderate quality). There was no significant improvement in the risk of vomiting, diarrhea, intensive care unit (ICU) length of stay or mortality. Prokinetic agents also did not significantly increase the rate of diarrhea. CONCLUSION: There is moderate-quality evidence that prokinetic agents reduce feeding intolerance in critically ill patients compared to placebo or no intervention. However, the impact on other clinical outcomes such as pneumonia, mortality, and ICU length of stay is unclear

Community-powered urban stream restoration: A vision for sustainable and resilient urban ecosystems

Este artículo contiene 16 páginas, 2 tablas, 3 figuras.Urban streams can provide amenities to people living in cities, but those benefits are reduced when streams become degraded, potentially even causing harm (disease, toxic compounds, etc.). Governments and institutions invest resources to improve the values and services provided by urban streams; however, the conception, development, and implementation of such projects may not include meaningful involvement of community members and other stakeholders. Consequently, project objectives may be misaligned with community desires and needs, and projects may fail to achieve their goals. In February 2020, the 5th Symposium on Urbanization and Stream Ecology, an interdisciplinary meeting held every 3 to 5 y, met in Austin, Texas, USA, to explore new approaches to urban stream projects, including ways to maximize the full range of potential benefits by better integrating community members into project identification and decision making. The symposium included in-depth discussion about 4 nearby field case studies, participation of multidisciplinary urban stream experts from 5 continents, and input from the Austin community. Institutional barriers to community inclusion were identified and analyzed using real-world examples, both from the case studies and from the literature, which clarified disparities in power, equity, and values. Outcomes of the symposium have been aggregated into a vision that challenges the present institutional approach to urban stream management and a set of strategies to systematically address these barriers to improve restoration solutions. Integrating community members and other stakeholders throughout the urban restoration process, and a transparent decision-making process to resolve divergent objectives, can help identify appropriate goals for realizing both the ecological and social benefits of stream restoration.Publication costs were covered by an award from the Society of Freshwater Science’s Endowed Publication Fund (https:// freshwater-science.org/publications/endowed-publication-fund).Peer reviewe

Global human footprint on the linkage between biodiversity and ecosystem functioning in reef fishes

Copyright: © 2011 Mora et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Difficulties in scaling up theoretical and experimental results have raised controversy over the consequences of biodiversity loss for the functioning of natural ecosystems. Using a global survey of reef fish assemblages, we show that in contrast to previous theoretical and experimental studies, ecosystem functioning (as measured by standing biomass) scales in a non-saturating manner with biodiversity (as measured by species and functional richness) in this ecosystem. Our field study also shows a significant and negative interaction between human population density and biodiversity on ecosystem functioning (i.e., for the same human density there were larger reductions in standing biomass at more diverse reefs). Human effects were found to be related to fishing, coastal development, and land use stressors, and currently affect over 75% of the world's coral reefs. Our results indicate that the consequences of biodiversity loss in coral reefs have been considerably underestimated based on existing knowledge and that reef fish assemblages, particularly the most diverse, are greatly vulnerable to the expansion and intensity of anthropogenic stressors in coastal areas