700 research outputs found

    Evolutionary Computing Methods for Spectral Retrieval

    Get PDF
    A methodology for processing spectral images to retrieve information on underlying physical, chemical, and/or biological phenomena is based on evolutionary and related computational methods implemented in software. In a typical case, the solution (the information that one seeks to retrieve) consists of parameters of a mathematical model that represents one or more of the phenomena of interest. The methodology was developed for the initial purpose of retrieving the desired information from spectral image data acquired by remote-sensing instruments aimed at planets (including the Earth). Examples of information desired in such applications include trace gas concentrations, temperature profiles, surface types, day/night fractions, cloud/aerosol fractions, seasons, and viewing angles. The methodology is also potentially useful for retrieving information on chemical and/or biological hazards in terrestrial settings. In this methodology, one utilizes an iterative process that minimizes a fitness function indicative of the degree of dissimilarity between observed and synthetic spectral and angular data. The evolutionary computing methods that lie at the heart of this process yield a population of solutions (sets of the desired parameters) within an accuracy represented by a fitness-function value specified by the user. The evolutionary computing methods (ECM) used in this methodology are Genetic Algorithms and Simulated Annealing, both of which are well-established optimization techniques and have also been described in previous NASA Tech Briefs articles. These are embedded in a conceptual framework, represented in the architecture of the implementing software, that enables automatic retrieval of spectral and angular data and analysis of the retrieved solutions for uniqueness

    Perioperative statin therapy reduces mortality in normolipidemic patients undergoing cardiac surgery

    Get PDF
    ObjectiveStatins might have pleiotropic effects, independent of their ability to reduce lipid levels. Recent data have suggested that statins improve early survival and cardiovascular outcomes after coronary artery bypass graft surgery. The effectiveness of statin therapy in normolipidemic cardiac surgery patients is as yet unclear.MethodsWe evaluated 3056 consecutive patients who had undergone cardiac surgery between April 2004 and April 2009. Perioperative statin therapy was defined as continued treatment both before (≥ 6 months) and after the index surgery (included as a discharge medication). Hyperlipidemia (HL) was defined as a total cholesterol level greater than 200 mg/dL within 6 months before surgery. Four groups were analyzed: (1) statin-untreated normolipidemic (NL−, n = 1052); (2) statin-treated normolipidemic (NL+, n = 206); (3) statin-untreated hyperlipidemic (HL−, n = 638); and (4) statin-treated hyperlipidemic (HL+, n = 1160) patients. Adjusted hazard ratios accounted for the known preoperative cardiac risk factors. Mortality was ascertained by retrospective database review and the Social Security Death Index.ResultsThe mean follow-up was 2.2 years. The crude rate of 30-day mortality was 3.0% (32/1052), 0% (0/206), 8.0% (51/638), and 0.7% (8/1160) for the NL−, NL+, HL−, and HL+ groups, respectively. The overall all-cause crude mortality rate was 9.6% (101/1052), 3.9% (8/206), 17.2% (110/638), and 6.5% (75/1160) for the NL−, NL+, HL−, and HL+ groups, respectively. Statin therapy for NL patients undergoing cardiac surgery independently reduced the overall all-cause mortality (adjusted hazard ratio, 0.34; 95% confidence interval, 0.16–0.71; P = .004).ConclusionsPerioperative statin therapy was associated with reduced mid-term mortality for patients undergoing cardiac surgery, irrespective of their baseline lipid status. This clinical evidence suggests that the beneficial effects of statins might extend beyond their lipid-lowering ability

    No substantial changes in estrogen receptor and estrogen-related receptor orthologue gene transcription in Marisa cornuarietis exposed to estrogenic chemicals

    Get PDF
    This article is made available through the Brunel Open Access Publishing Fund. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-No Derivative Works License, which permits non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited.Estrogen receptor orthologues in molluscs may be targets for endocrine disruptors, although mechanistic evidence is lacking. Molluscs are reported to be highly susceptible to effects caused by very low concentrations of environmental estrogens which, if substantiated, would have a major impact on the risk assessment of many chemicals. The present paper describes the most thorough evaluation to-date of the susceptibility of Marisa cornuarietis ER and ERR gene transcription to modulation by vertebrate estrogens in vivo and in vitro. We investigated the effects of estradiol-17β and 4-tert-Octylphenol exposure on in vivo estrogen receptor (ER) and estrogen-related receptor (ERR) gene transcription in the reproductive and neural tissues of the gastropod snail M. cornuarietis over a 12-week period. There was no significant effect (p > 0.05) of treatment on gene transcription levels between exposed and non-exposed snails. Absence of a direct interaction of estradiol-17β and 4-tert-Octylphenol with mollusc ER and ERR protein was also supported by in vitro studies in transfected HEK-293 cells. Additional in vitro studies with a selection of other potential ligands (including methyl-testosterone, 17α-ethinylestradiol, 4-hydroxytamoxifen, diethylstilbestrol, cyproterone acetate and ICI182780) showed no interaction when tested using this assay. In repeated in vitro tests, however, genistein (with mcER-like) and bisphenol-A (with mcERR) increased reporter gene expression at high concentrations only (>10−6 M for Gen and >10−5 M for BPA, respectively). Like vertebrate estrogen receptors, the mollusc ER protein bound to the consensus vertebrate estrogen-response element (ERE). Together, these data provide no substantial evidence that mcER-like and mcERR activation and transcript levels in tissues are modulated by the vertebrate estrogen estradiol-17β or 4-tert-Octylphenol in vivo, or that other ligands of vertebrate ERs and ERRs (with the possible exception of genistein and bisphenol A, respectively) would do otherwise.BBSR

    Heme metabolism genes Downregulated in COPD Cachexia.

    Get PDF
    IntroductionCachexia contributes to increased mortality and reduced quality of life in Chronic Obstructive Pulmonary Disease (COPD) and may be associated with underlying gene expression changes. Our goal was to identify differential gene expression signatures associated with COPD cachexia in current and former smokers.MethodsWe analyzed whole-blood gene expression data from participants with COPD in a discovery cohort (COPDGene, N = 400) and assessed replication (ECLIPSE, N = 114). To approximate the consensus definition using available criteria, cachexia was defined as weight-loss > 5% in the past 12 months or low body mass index (BMI) (< 20 kg/m2) and 1/3 criteria: decreased muscle strength (six-minute walk distance < 350 m), anemia (hemoglobin < 12 g/dl), and low fat-free mass index (FFMI) (< 15 kg/m2 among women and < 17 kg/m2 among men) in COPDGene. In ECLIPSE, cachexia was defined as weight-loss > 5% in the past 12 months or low BMI and 3/5 criteria: decreased muscle strength, anorexia, abnormal biochemistry (anemia or high c-reactive protein (> 5 mg/l)), fatigue, and low FFMI. Differential gene expression was assessed between cachectic and non-cachectic subjects, adjusting for age, sex, white blood cell counts, and technical covariates. Gene set enrichment analysis was performed using MSigDB.ResultsThe prevalence of COPD cachexia was 13.7% in COPDGene and 7.9% in ECLIPSE. Fourteen genes were differentially downregulated in cachectic versus non-cachectic COPD patients in COPDGene (FDR < 0.05) and ECLIPSE (FDR < 0.05).DiscussionSeveral replicated genes regulating heme metabolism were downregulated among participants with COPD cachexia. Impaired heme biosynthesis may contribute to cachexia development through free-iron buildup and oxidative tissue damage

    An 83 000-year-old ice core from Roosevelt Island, Ross Sea, Antarctica

    Get PDF
    In 2013 an ice core was recovered from Roosevelt Island, an ice dome between two submarine troughs carved by paleo-ice-streams in the Ross Sea, Antarctica. The ice core is part of the Roosevelt Island Climate Evolution (RICE) project and provides new information about the past configuration of the West Antarctic Ice Sheet (WAIS) and its retreat during the last deglaciation. In this work we present the RICE17 chronology, which establishes the depth–age relationship for the top 754 m of the 763 m core. RICE17 is a composite chronology combining annual layer interpretations for 0–343 m (Winstrup et al., 2019) with new estimates for gas and ice ages based on synchronization of CH4 and δ18Oatm records to corresponding records from the WAIS Divide ice core and by modeling of the gas age–ice age difference. Novel aspects of this work include the following: (1) an automated algorithm for multiproxy stratigraphic synchronization of high-resolution gas records; (2) synchronization using centennial-scale variations in methane for pre-anthropogenic time periods (60–720 m, 1971 CE to 30 ka), a strategy applicable for future ice cores; and (3) the observation of a continuous climate record back to ∼65 ka providing evidence that the Roosevelt Island Ice Dome was a constant feature throughout the last glacial period

    The Manokwari Declaration: Challenges ahead in conserving 70% of Tanah Papua’s forests

    Get PDF
    The Manokwari Declaration is an unprecedented pledge by the governors of Indonesia’s two New Guinea provinces to promote conservation and become SE Asia’s new Costa Rica. This is an exciting, yet challenging endeavour that will require working on many fronts that transcend single disciplines. Because Indonesian New Guinea has the largest expanse of intact forests in SE Asia, large-scale conservation pledges like the Manokwari Declaration will have a global impact on biodiversity conservation and climate change mitigation

    Investigation of Electron Transfer-Based Photonic and Electro-Optic Materials and Devices

    Get PDF
    Montanaâs state program began its sixth year in 2006. The projectâs research cluster focused on physical, chemical, and biological materials that exhibit unique electron-transfer properties. Our investigators have filed several patents and have also have established five spin-off businesses (3 MSU, 2 UM) and a research center (MT Tech). In addition, this project involved faculty and students at three campuses (MSU, UM, MT Tech) and has a number of under-represented students, including 10 women and 5 Native Americans. In 2006, there was an added emphasis on exporting seminars and speakers via the Internet from UM to Chief Dull Knife Community College, as well as work with the MT Department of Commerce to better educate our faculty regarding establishing small businesses, licensing and patent issues, and SBIR program opportunities
    • …
    corecore