194 research outputs found
The Lantern Vol. 45, No. 1, November 1978
⢠Here is the Dance ⢠To V.E.H. ⢠The Hard Fist of the North ⢠Early Ridicule ⢠Spectrum - October 6, 1978 ⢠Finally Someone Looks ⢠Windjammer ⢠Bereft ⢠Waiting ⢠Solitary Season ⢠Drifting Downstream ⢠The Dirtiest Joke ⢠The Mannequin Factory ⢠Me ⢠When I am Famous ⢠A Letter to John Hansen ⢠Who Said the Sound of Laughter is Nice? ⢠Throwing Back Her Hair ⢠Don\u27t Let the Cold Become You ⢠Sister ⢠Marxist Drama ⢠Fleeting Love ⢠Music of Spain ⢠(A Selection of Happy Poems) ⢠Sterling St. Jacques ⢠Winter, Verse II ⢠Aventure Chez Le Psychiatre ⢠For Marya ⢠The Night Train ⢠A Rude Awakeninghttps://digitalcommons.ursinus.edu/lantern/1113/thumbnail.jp
Remarkable preservation of microbial mats in Neoproterozoic siliciclastic settings : Implications for Ediacaran taphonomic models
The authors thank Duncan McIlroy and Alex Liu for their discussions, help, comments and field support, the National Trust for access to Longmyndian localities, and the staff of the British Geological Survey Palaeontology unit and the Oxford University Museum of Natural History for their assistance with access to materials. The comments and suggestions of two anonymous reviewers and Nora Noffke significantly improved the manuscript.Peer reviewedPostprin
Dynamic redox conditions control late Ediacaran metazoan ecosystems in the Nama Group, Namibia
The first appearance of skeletal metazoans in the late Ediacaran (~550 million years ago; Ma) has been linked to the widespread development of oxygenated oceanic conditions, but a precise spatial and temporal reconstruction of their evolution has not been resolved. Here we consider the evolution of ocean chemistry from ~550 to ~541. Ma across shelf-to-basin transects in the Zaris and Witputs Sub-Basins of the Nama Group, Namibia. New carbon isotope data capture the final stages of the Shuram/Wonoka deep negative C-isotope excursion, and these are complemented with a reconstruction of water column redox dynamics utilising Fe-S-C systematics and the distribution of skeletal and soft-bodied metazoans. Combined, these inter-basinal datasets provide insight into the potential role of ocean redox chemistry during this pivotal interval of major biological innovation.The strongly negative δ13C values in the lower parts of the sections reflect both a secular, global change in the C-isotopic composition of Ediacaran seawater, as well as the influence of 'local' basinal effects as shown by the most negative δ13C values occurring in the transition from distal to proximal ramp settings. Critical, though, is that the transition to positive δ13C values postdates the appearance of calcified metazoans, indicating that the onset of biomineralization did not occur under post-excursion conditions.Significantly, we find that anoxic and ferruginous deeper water column conditions were prevalent during and after the transition to positive δ13C that marks the end of the Shuram/Wonoka excursion. Thus, if the C isotope trend reflects the transition to global-scale oxygenation in the aftermath of the oxidation of a large-scale, isotopically light organic carbon pool, it was not sufficient to fully oxygenate the deep ocean.Both sub-basins reveal highly dynamic redox structures, where shallow, inner ramp settings experienced transient oxygenation. Anoxic conditions were caused either by episodic upwelling of deeper anoxic waters or higher rates of productivity. These settings supported short-lived and monospecific skeletal metazoan communities. By contrast, microbial (thrombolite) reefs, found in deeper inner- and mid-ramp settings, supported more biodiverse communities with complex ecologies and large skeletal metazoans. These long-lived reef communities, as well as Ediacaran soft-bodied biotas, are found particularly within transgressive systems, where oxygenation was persistent. We suggest that a mid-ramp position enabled physical ventilation mechanisms for shallow water column oxygenation to operate during flooding and transgressive sea-level rise. Our data support a prominent role for oxygen, and for stable oxygenated conditions in particular, in controlling both the distribution and ecology of Ediacaran skeletal metazoan communities
Effect of denosumab versus zoledronic acid in preventing skeletal-related events in patients with bone metastases by baseline characteristics
Background: Analyses of phase III trials showed that denosumab was superior to
zoledronic acid (ZA) in preventing skeletal-related events (SREs) irrespective of age, history of
SREs, or baseline pain status. This analysis assessed the risk of SREs across additional baseline
characteristics.
Patients and Methods: Patients (N Z 5543) from three phase III trials who had breast cancer,
prostate cancer, or other solid tumours and one or more bone metastasis were included. Superiority
of denosumab versus ZA in reducing risk of first SRE and first and subsequent SREs
was assessed in subgroups defined by the Eastern Cooperative Oncology Group performance status (ECOG PS), bone metastasis location, bone metastasis number, visceral metastasis presence/absence,
and urinary N-telopeptide (uNTx) level using Cox proportional hazards and
AndersoneGill models. Subgroups except bone metastasis location were also assessed for each
solid tumour type.
Results: Compared with ZA, denosumab significantly reduced the risk of first SRE
across all subgroups (hazard ratio [HR] ranges: ECOG PS, 0.79e0.84; bone metastasis location,
0.78e0.83; bone metastasis number, 0.78e0.84; visceral metastasis presence/absence,
0.80e0.82; uNTx level, 0.73e0.86) and reduced the risk of first and subsequent SREs in all
subgroups (HR ranges: ECOG PS, 0.76e0.83; bone metastasis location, 0.78e0.84; bone
metastasis number, 0.79e0.81; visceral metastasis presence/absence, 0.79e0.81; uNTx level,
0.74e0.83). Similar results were observed in subgroups across tumour types.
Conclusion: Denosumab was superior to ZA in preventing SREs in patients with bone metastases
from advanced cancer, regardless of ECOG PS, bone metastasis number, baseline
visceral metastasis presence/absence, and uNTx leve
The Intriguing Effects of Substituents in the N-Phenethyl Moiety of Norhydromorphone: A Bifunctional Opioid from a Set of âTail Wags Dogâ Experiments
This work is licensed under a Creative Commons Attribution 4.0 International License.(â)-N-Phenethyl analogs of optically pure N-norhydromorphone were synthesized and pharmacologically evaluated in several in vitro assays (opioid receptor binding, stimulation of [35S]GTPÎłS binding, forskolin-induced cAMP accumulation assay, and MOR-mediated β-arrestin recruitment assays). âBodyâ and âtailâ interactions with opioid receptors (a subset of Portogheseâs message-address theory) were used for molecular modeling and simulations, where the âaddressâ can be considered the âbodyâ of the hydromorphone molecule and the âmessageâ delivered by the substituent (tail) on the aromatic ring of the N-phenethyl moiety. One compound, N-p-chloro-phenethynorhydromorphone ((7aR,12bS)-3-(4-chlorophenethyl)-9-hydroxy-2,3,4,4a,5,6-hexahydro-1H-4,12-methanobenzofuro[3,2-e]isoquinolin-7(7aH)-one, 2i), was found to have nanomolar binding affinity at MOR and DOR. It was a potent partial agonist at MOR and a full potent agonist at DOR with a δ/Îź potency ratio of 1.2 in the ([35S]GTPÎłS) assay. Bifunctional opioids that interact with MOR and DOR, the latter as agonists or antagonists, have been reported to have fewer side-effects than MOR agonists. The p-chlorophenethyl compound 2i was evaluated for its effect on respiration in both mice and squirrel monkeys. Compound 2i did not depress respiration (using normal air) in mice or squirrel monkeys. However, under conditions of hypercapnia (using air mixed with 5% CO2), respiration was depressed in squirrel monkeys.NIDA grant P30 DA13429NIDA grant DA039997NIDA grant DA018151NIDA grant DA035857NIDA grant DA047574NIH Intramural Research Programs of the National Institute on Drug AbuseNational Institute of Alcohol Abuse and AlcoholismNIH Intramural Research Programs of the National Institute on Drug AbuseNIH Intramural Research Program through the Center for Information TechnologyNIH Intramural Research Programs of the National Institute on Drug Abus
Assessing progress towards meeting major international objectives related to nature and nature's contributions to people
In recognition of the importance of nature, its contributions to people and role in underpinning sustainable development, governments adopted a Strategic Plan on Biodiversity 2011-2020 through the Convention on Biological Diversity (CBD) containing 20 "Aichi Biodiversity Targets" and integrated many of these into the Sustainable Development Goals (SDGs) adopted through the United Nations in 2015. Additional multilateral environmental agreements (MEAs) target particular aspects of nature (e.g., Ramsar Convention on Wetlands; Convention on Migratory Species), drivers of biodiversity loss (e.g., Convention on International Trade in Endangered Species of Wild Fauna and Flora), or responses (e.g., World Heritage Convention). These various MEAs provide complementary fora in which governments strive to coordinate efforts to reduce the loss and degradation of nature, and to promote sustainable development. In this chapter, we assess, through a systematic review process and quantitative analysis of indicators, progress towards the 20 Aichi Targets under the Strategic Plan (and each of the 54 elements or components of these targets), targets under the SDGs that are relevant to nature and nature's contributions to people (NCP), and the goals and targets of six other MEAs. We consider the relationships between the SDGs, nature and the contributions of Indigenous Peoples and Local Communities (IPLCs) to achieving the various targets and goals, the impact of progress or lack of it on IPLCs, the reasons for variation in progress, implications for a new Strategic Plan for Biodiversity beyond 2020, and key knowledge gaps.For the 44 SDG targets assessed, including targets for poverty, hunger, health, water, cities, climate, oceans and land (Goals 1, 2, 3, 6, 11, 13, 14, 15), findings suggest that current negative trends in nature will substantially undermine progress to 22 SDG targets and result in insufficient progress to meet 13 additional targets (i.e. 80 per cent (35 out of 44) of the assessed targets) {3.3.2.1; 3.3.2.2}(established but incomplete). Across terrestrial, aquatic and marine ecosystems, current negative trends in nature and its contributions will hamper SDG progress, with especially poor progress expected towards targets on water security, water quality, ocean pollution and acidification. Trends in nature's contributions relevant to extreme event vulnerability, resource access, small-scale food production, and urban and agricultural sustainability are negative and insufficient for achieving relevant targets under SDGs 1, 2, 3, and 11. This has negative consequences for both the rural and urban poor who are also directly reliant on declining resources for consumption and income generation {3.3.2.2}. For a further 9 targets evaluated in SDGs 1, 3 and 11 a lack of knowledge on how nature contributes to targets (4 targets) or gaps in data with which to assess trends in nature (5 targets) prevented their assessment.Fil: Butchart, Stuart. London Metropolitan University; Reino UnidoFil: Miloslavich, Patricia. University of Western Australia; AustraliaFil: Reyers, Belinda. No especifĂca;Fil: Galetto, Leonardo. Consejo Nacional de Investigaciones CientĂficas y TĂŠcnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto Multidisciplinario de BiologĂa Vegetal. Universidad Nacional de CĂłrdoba. Facultad de Ciencias Exactas FĂsicas y Naturales. Instituto Multidisciplinario de BiologĂa Vegetal; ArgentinaFil: Subramanian, Suneetha M.. No especifĂca;Fil: Adams, Cristina. No especifĂca;Fil: Palomo, Maria Gabriela. Consejo Nacional de Investigaciones CientĂficas y TĂŠcnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: McElwee, Pamela. No especifĂca;Fil: Meretsky, Vicky J.. No especifĂca;Fil: Morsello, Carla. No especifĂca;Fil: Nel, Jeanne. No especifĂca;Fil: Lynn Newberry, Teresa. No especifĂca;Fil: Pacheco, Diego. No especifĂca;Fil: Pyhala, Aili. No especifĂca;Fil: Rossi Heras, Sergio. No especifĂca;Fil: Roy, Joyashree. No especifĂca;Fil: Ruiz-MallĂŠn, Isabel. No especifĂca;Fil: Salpeteur, Matthieu. No especifĂca;Fil: Santos-Martin, Fernando. No especifĂca;Fil: Saylor. Kirk. No especifĂca;Fil: Schaffartzik, Anke. No especifĂca;Fil: Sitas, Nadia. No especifĂca;Fil: Speranza, Ifejika. No especifĂca;Fil: Suich, Helen. No especifĂca;Fil: Tittensor, Derek. No especifĂca;Fil: Carignano, Patricia. No especifĂca;Fil: Tsioumani, Elsa. No especifĂca;Fil: Whitmee, Sarah. No especifĂca;Fil: Wilson, Sarah. No especifĂca;Fil: Wyndham, Felice. No especifĂca;Fil: Zorondo-Rodriguez, Francisco. No especifĂca
Controls on the evolution of Ediacaran metazoan ecosystems: A redox perspective
A growing number of detailed geochemical studies of Ediacaran (635â541 Ma) marine successions have provided snapshots into the redox environments that played host to the earliest known metazoans. Whilst previous compilations have focused on the global evolution of Ediacaran water column redox chemistry, the inherent heterogeneity evident in palaeogeographically distinct environments demands a more dissected approach to better understand the nature, interactions and evolution of extrinsic controls on the development of early macrobenthic ecosystems. Here, we review available data of local-scale redox conditions within a palaeogeographic and sequence stratigraphic framework, to explore the mechanisms controlling water column redox conditions and their potential impact on the record of metazoans. The openly connected Laurentian margin, North America (632â540 Ma) and Nama basin, Namibia (550â538 Ma), and the variably restricted Yangtze Block, South China (635â520 Ma), show continued redox instability after the first fossil evidence for metazoans. This may support opportunistic benthic colonisation during periods of transient oxygenation amidst episodic upwelling of anoxic waters beneath a very shallow, fluctuating chemocline. The first skeletal metazoans appeared under conditions of continued redox stratification, such as those which characterise the Dengying Formation of the Yangtze Block and the Kuibis Subgroup of the Nama basin. Current data, however, suggests that successful metazoan reef-building demanded more persistent oxia. We propose that cratonic positioning and migration throughout the Ediacaran Period, in combination with gradually increasing dissolved oxygen loading, may have provided a first-order control on redox evolution through regulating circulation mechanisms in the Mirovian Ocean. Some unrestricted lower slope environments from mid-high latitudes benefited from sustained oxygenation via downwelling, whilst transit of isolated cratons towards more equatorial positions stifled pervasive ventilation either through ineffective surface ocean mixing, Ekman-induced upwelling, elevated surface ocean productivity or a combination of these processes
Background ozone over the United States in summer: Origin, trend, and contribution to pollution episodes
Observations indicate that ozone (O3) concentrations in surface air over the United States in summer contain a 20â45 ppbv background contribution, presumably reflecting transport from outside the North American boundary layer. We use a three-dimensional global model of tropospheric chemistry driven by assimilated meteorological observations to investigate the origin of this background and to quantify its contribution to total surface O3 on both average and highly polluted summer days. The model simulation is evaluated with a suite of surface and aircraft observations over the United States from the summer of 1995. The model reproduces the principal features in the observed distributions of O3 and its precursors, including frequency distributions of O3 concentrations and the development of regional high-O3 episodes in the eastern United States. Comparison of simulations with 1995 versus 1980 global fossil fuel emissions indicates that the model captures the previously observed decrease in the high end of the O3 probability distribution in surface air over the United States (reflecting reduction of domestic hydrocarbon emissions) and the increase in the low end (reflecting, at least in the model, rising Asian emissions). In the model, background O3 produced outside of the North American boundary layer contributes an average 25â35 ppbv to afternoon O3 concentrations in surface air in the western United States. and 15â30 ppbv in the eastern United States during the summer of 1995. This background generally decays to below 15 ppbv during the stagnation conditions conducive to exceedances of the 8-hour 0.08 ppmv (80 ppbv) National Ambient Air Quality Standard (NAAQS) for O3. A high background contribution of 25â40 ppbv is found during 9% of these exceedances, reflecting convective mixing of free tropospheric O3 from aloft, followed by rapid production within the U.S. boundary layer. Anthropogenic emissions in Asia and Europe are found to increase afternoon O3 concentrations in surface air over the United States by typically 4â7 ppbv, under both average and highly polluted conditions. This enhancement is particularly large (up to 14 ppbv) for O3 concentrations in the 50â70 ppbv range, and would represent a major concern if the NAAQS were to be tightened
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