2,833 research outputs found

    Node-Negative Non-small Cell Lung Cancer: Pathological Staging and Survival in 1765 Consecutive Cases

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    IntroductionThis study aimed to evaluate prognostic factors in patients with node-negative non-small cell lung cancer and to assess revised International Association for the Study of Lung Cancer staging recommendations for this group.MethodsA retrospective analysis of 1765 consecutive pathologically node-negative patients treated by surgical resection between 1984 and 2007 was performed. Survival analysis was conducted using the Kaplan-Meier method. The independence of prognostic factors was analyzed using multivariate Cox proportional hazards modeling.ResultsThe median age of patients was 68 years, and the average length of follow-up was 6.3 years. Perioperative mortality was 1.7%. The median survival was 6.5 years, with a 56% of the cohort surviving 5 years. Factors associated with poorer prognosis were male gender (hazard ratio [HR]: 1.30, p = <0.001), age (HR: 1.04 per year of increase, p < 0.001), limited resection (HR: 1.30, p = 0.002) tumor size (HR: 1.10 per 10 mm increase, p < 0.001), large cell histopathological cell type (HR: 1.35, p < 0.001), and positive resection margins (HR: 1.58, p = 0.002). T stage was a superior predictor of survival than tumor size (p < 0.001). There was no difference in survival by T-stage descriptor within stage T2 or T3.ConclusionsIn surgically treated, node-negative non-small cell lung cancer, revised International Association for the Study of Lung Cancer staging criteria stratify survival well. Age, gender, and extent of resection are also important predictors of survival. Current T-stage descriptor groupings are appropriate

    Mind the gap: comparing exploration effort with global biodiversity patterns and climate projections to determine ocean areas with greatest exploration needs

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    The oceans contain 1,335 million km3 of water covering 361.9 million km2 of seafloor across 71% of the planet. In the past few decades, there has been substantial effort put into mapping and exploring the ocean fueled by the advent of new technologies that more easily enable deepwater access. However, we are still far from achieving our shared goals of a well characterized and documented ocean. In 2010, Webb etΒ al. documented the paucity of deep-sea data in general, with a specific focus on the lack of pelagic records in the Ocean Biogeographic Information System OBIS, which is the largest of the ocean biodiversity archives. While significant exploration progress has been made, the rate of change in the ocean is outstripping the rate of characterization and research. Given the limited resources available, future work needs to be prioritized to focus on areas of greatest need. Here, we investigated several lines of inquiry to determine priority areas for future exploration. We accumulated the largest database of global deep submergence dive records ever compiled and used it, plus OBIS biodiversity records, to assess the level of exploration in different ocean regions. Then, we compared these measures of exploration effort with different biogeographic province schemas and estimates of climate change velocity projections to identify the largest remaining gaps in exploration and research sampling. Given that marine science has only explored between 5 and 20% of the ocean (depending on estimates) in the last hundred and fifty years, future exploration needs to be more targeted to attempt to keep pace with the rate and impact of environmental and biodiversity change in the ocean

    Temperature and Precipitation Affect Seasonal Patterns of Dispersing Tobacco Thrips, Frankliniella fusca, and Onion Thrips, Thrips tabaci (Thysanoptera: Thripidae) Caught on Sticky Traps

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    Effects of temperature and precipitation on the temporal patterns of dispersing tobacco thrips, Frankliniella fusca, and onion thrips, Thrips tabaci, caught on yellow sticky traps were estimated in central and eastern North Carolina and eastern Virginia from 1997 through 2001. The impact that these environmental factors had on numbers of F. fusca and T. tabaci caught on sticky traps during April and May was determined using stepwise regression analysis of 43 and 38 site-years of aerial trapping data from 21 and 18 different field locations, respectively. The independent variables used in the regression models included degree-days, total precipitation, and the number of days in which precipitation occurred during January through May. Each variable was significant in explaining variation for both thrips species and, in all models, degree-days was the single best explanatory variable. Precipitation had a comparatively greater effect on T. tabaci than F. fusca. The numbers of F. fusca and T. tabaci captured in flight were positively related to degree-days and the number of days with precipitation but negatively related to total precipitation. Combined in a single model, degree-days, total precipitation, and the number of days with precipitation explained 70 and 55% of the total variation in the number of F. fusca captured from 1 April through 10 May and from 1 April through 31 May, respectively. Regarding T. tabaci flights, degree-days, total precipitation, and the number of days with precipitation collectively explained 57 and 63% of the total variation in the number captured from 1 April through 10 May and from 1 April through 31 May, respectivel

    Cruise Report: EX-17-11 Gulf of Mexico 2017 (ROV and Mapping)

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    From November 29, 2017 to December 21, 2017, the NOAA Office of Ocean Exploration and Research (OER) and partners conducted a telepresence-enabled ocean exploration expedition on NOAA Ship Okeanos Explorer to collect critical baseline data and information and to improve knowledge about unexplored and poorly understood deepwater areas of the Gulf of Mexico. The Gulf of Mexico 2017 (EX-17-11) expedition was part of a series of expeditions between 2017 and 2018 that explored deepwater areas in the Gulf of Mexico. During 23 days at sea, 17 remotely operated vehicle (ROV) dives were completed off the Western Florida Escarpment and in the central and western Gulf of Mexico. Over 93 hours of ROV bottom time were logged at depths between 300 and 2,321 meters. Over 20,000 square kilometers of seafloor were mapped. A total of 138 biological and 11 geological samples were collected. The expedition gathered over 280,000 live video views worldwide and the OER website received over 35,600 views. A core onshore science team of over 80 participants from around the world collaborated and supported real-time ocean exploration science. The data associated with this expedition have been archived and are publicly available through the NOAA Archives

    Instability in the Molecular Dynamics Step of Hybrid Monte Carlo in Dynamical Fermion Lattice QCD Simulations

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    We investigate instability and reversibility within Hybrid Monte Carlo simulations using a non-perturbatively improved Wilson action. We demonstrate the onset of instability as tolerance parameters and molecular dynamics step sizes are varied. We compare these findings with theoretical expectations and present limits on simulation parameters within which a stable and reversible algorithm is obtained for physically relevant simulations. Results of optimisation experiments with respect to tolerance prarameters are also presented

    Instability in the molecular dynamics step of a hybrid Monte Carlo algorithm in dynamical fermion lattice QCD simulations

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    We investigate instability and reversibility within Hybrid Monte Carlo simulations using a non-perturbatively improved Wilson action. We demonstrate the onset of instability as tolerance parameters and molecular dynamics step sizes are varied. We compare these findings with theoretical expectations and present limits on simulation parameters within which a stable and reversible algorithm is obtained for physically relevant simulations. Results of optimisation experiments with respect to tolerance prarameters are also presented.Comment: RevTeX, Some results here were presented at Vielat 99, Vienna, Austria, Sept 1999 22 Pages, 10 figures, to be submitted to PR

    Solution structure of a repeated unit of the ABA-1 nematode polyprotein allergen of ascaris reveals a novel fold and two discrete lipid-binding sites

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    Parasitic nematode worms cause serious health problems in humans and other animals. They can induce allergic-type immune responses, which can be harmful but may at the same time protect against the infections. Allergens are proteins that trigger allergic reactions and these parasites produce a type that is confined to nematodes, the nematode polyprotein allergens (NPAs). These are synthesized as large precursor proteins comprising repeating units of similar amino acid sequence that are subsequently cleaved into multiple copies of the allergen protein. NPAs bind small lipids such as fatty acids and retinol (Vitamin A) and probably transport these sensitive and insoluble compounds between the tissues of the worms. Nematodes cannot synthesize these lipids, so NPAs may also be crucial for extracting nutrients from their hosts. They may also be involved in altering immune responses by controlling the lipids by which the immune and inflammatory cells communicate. We describe the molecular structure of one unit of an NPA, the well-known ABA-1 allergen of Ascaris and find its structure to be of a type not previously found for lipid-binding proteins, and we describe the unusual sites where lipids bind within this structur

    Decreased Proliferation Kinetics of Mouse Myoblasts Overexpressing FRG1

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    Although recent publications have linked the molecular events driving facioscapulohumeral muscular dystrophy (FSHD) to expression of the double homeobox transcription factor DUX4, overexpression of FRG1 has been proposed as one alternative causal agent as mice overexpressing FRG1 present with muscular dystrophy. Here, we characterize proliferative defects in two independent myoblast lines overexpressing FRG1. Myoblasts isolated from thigh muscle of FRG1 transgenic mice, an affected dystrophic muscle, exhibit delayed proliferation as measured by decreased clone size, whereas myoblasts isolated from the unaffected diaphragm muscle proliferated normally. To confirm the observation that overexpression of FRG1 could impair myoblast proliferation, we examined C2C12 myoblasts with inducible overexpression of FRG1, finding increased doubling time and G1-phase cells in mass culture after induction of FRG1 and decreased levels of pRb phosphorylation. We propose that depressed myoblast proliferation may contribute to the pathology of mice overexpressing FRG1 and may play a part in FSHD

    Thermodynamic Constraints on Nitrogen Transformations and Other Biogeochemical Processes at Soil-Stream Interfaces

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    There is much interest in biogeochemical processes that occur at the interface between soils and streams since, at the scale of landscapes, these habitats may function as control points for fluxes of nitrogen (N) and other nutrients from terrestrial to aquatic ecosystems. Here we examine whether a thermodynamic perspective can enhance our mechanistic and predictive understanding of the biogeochemical function of soil-stream interfaces, by considering how microbial communities interact with variations in supplies of electron donors and acceptors. Over a two-year period we analyzed \u3e1400 individual samples of subsurface waters from networks of sample wells in riparian wetlands along Smith Creek, a first-order stream draining a mixed forested-agricultural landscape in southwestern Michigan, USA. We focused on areas where soil water and ground water emerged into the stream, and where we could characterize subsurface flow paths by measures of hydraulic head and/or by in situ additions of hydrologic tracers. We found strong support for the idea that the biogeochemical function of soil-stream interfaces is a predictable outcome of the interaction between microbial communities and supplies of electron donors and acceptors. Variations in key electron donors and acceptors (NO3βˆ’,N2O,NH4+,SO42βˆ’,CH4 role= presentation \u3eNO3βˆ’,N2O,NH4+,SO42βˆ’,CH4 ,, and dissolved organic carbon [DOC]) closely followed predictions from thermodynamic theory. Transformations of N and other elements resulted from the response of microbial communities to two dominant hydrologic flow paths: (1) horizontal flow of shallow subsurface waters with high levels of electron donors (i.e., DOC, CH4, and NH4+),, and (2) near-stream vertical upwelling of deep subsurface waters with high levels of energetically favorable electron acceptors (i.e., NO3-,N2O, and SO42-).. Our results support the popular notion that soil-stream interfaces can possess strong potential for removing dissolved N by denitrification. Yet in contrast to prevailing ideas, we found that denitrification did not consume all NO3- that reached the soil-stream interface via subsurface flow paths. Analyses of subsurface N chemistry and natural abundances of Ξ΄ 15N in NO3- and NH4+ suggested a narrow near-stream region as functionally the most important location for NO3- consumption by denitrification. This region was characterized by high throughput of terrestrially derived water, by accumulation of dissolved NO3- and N2O, and by low levels of DOC. Field experiments supported our hypothesis that the sustained ability for removal of dissolved NO3- and N2O should be limited by supplies of oxidizable carbon via shallow flowpaths. In situ additions of acetate, succinate, and propionate induced rates of NO3- removal (∼ 1.8 g NΒ· m-2Β· d-1) that were orders of magnitude greater than typically reported from riparian habitats. We propose that the immediate near-stream region may be especially important for determining the landscape-level function of many riparian wetlands. Management efforts to optimize the removal of NO3- by denitrification ought to consider promoting natural inputs of oxidizable carbon to this near-stream region
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