616 research outputs found

    An absolute calibration system for millimeter-accuracy APOLLO measurements

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    Lunar laser ranging provides a number of leading experimental tests of gravitation -- important in our quest to unify General Relativity and the Standard Model of physics. The Apache Point Observatory Lunar Laser-ranging Operation (APOLLO) has for years achieved median range precision at the ~2 mm level. Yet residuals in model-measurement comparisons are an order-of-magnitude larger, raising the question of whether the ranging data are not nearly as accurate as they are precise, or if the models are incomplete or ill-conditioned. This paper describes a new absolute calibration system (ACS) intended both as a tool for exposing and eliminating sources of systematic error, and also as a means to directly calibrate ranging data in-situ. The system consists of a high-repetition-rate (80 MHz) laser emitting short (< 10 ps) pulses that are locked to a cesium clock. In essence, the ACS delivers photons to the APOLLO detector at exquisitely well-defined time intervals as a "truth" input against which APOLLO's timing performance may be judged and corrected. Preliminary analysis indicates no inaccuracies in APOLLO data beyond the ~3 mm level, suggesting that historical APOLLO data are of high quality and motivating continued work on model capabilities. The ACS provides the means to deliver APOLLO data both accurate and precise below the 2 mm level.Comment: 21 pages, 10 figures, submitted to Classical and Quantum Gravit

    Global Antifungal Profile Optimization of Chlorophenyl Derivatives against Botrytis cinerea and Colletotrichum gloeosporioides

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    Twenty-two aromatic derivatives bearing a chlorine atom and a different chain in the para or meta position were prepared and evaluated for their in vitro antifungal activity against the phytopathogenic fungi Botrytis cinerea and Colletotrichum gloeosporioides. The results showed that maximum inhibition of the growth of these fungi was exhibited for enantiomers S and R of 1-(40-chlorophenyl)- 2-phenylethanol (3 and 4). Furthermore, their antifungal activity showed a clear structure-activity relationship (SAR) trend confirming the importance of the benzyl hydroxyl group in the inhibitory mechanism of the compounds studied. Additionally, a multiobjective optimization study of the global antifungal profile of chlorophenyl derivatives was conducted in order to establish a rational strategy for the filtering of new fungicide candidates from combinatorial libraries. The MOOPDESIRE methodology was used for this purpose providing reliable ranking models that can be used later

    Fenoles totales y actividad antioxidante en hojas de dos especies colombianas del género Meriania (melastomataceae)

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    Se estudiaron las hojas de las especies Merianiaspeciosa y Meriania nobilis, obteniendoextractos de diferente polaridad, a los que seles realizaron diversas pruebas cualitativas. Sedeterminó el contenido de fenoles totales y seevaluó la actividad captadora de radicales conDPPH (FRS50: capacidad captadora de radicalesque reduce en un 50% al radical DPPH)en microplacas de 96 pozos. Este estudiodeterminó que las dos especies presentan unabuena actividad antioxidante. Los extractosque mayor actividad antioxidante mostraronfueron: butanol con FRS50 de 7,6 ± 0,8 y 23,4± 2,4; acuoso con FRS50 de 28,5 ± 2,9 y 63,0± 2,6 y hexano 2 con FRS50 de 17,0 ± 2,6 y18,2 ± 2,5 mg/L, para las especies M. speciosay M. nobilis respectivamente. Los extractosque presentaron un alto contenido de fenolestotales fueron: metanol 2 con valor de 0,47 ±0,06 y 0,40 ± 0,03 mg equivalentes de ácidogálico (EAG)/g extracto seco (ES) y el extractoacuoso: 0,16 ± 0,06 y 0,12 ± 0,03 mg EAG/gES para las especies M. speciosa y M. nobilisrespectivamente. El extracto butanólico de laespecie M. speciosa mostró la mayor actividadantioxidante con un FRS50 de 7,6 mg/L ± 0,8,este valor es comparable con el valor halladopara la quercetina FRS50: 4,2 mg/L ± 0,4, loque indica que este extracto es promisorioen el contenido de metabolitos secundariosque exhiben actividad antioxidante y parala fabricación de productos agroquímicos,cosméticos y farmacéuticos

    Super Typhoon Bopha and the Mayo River Debris-Flow Disaster, Mindanao, Philippines, December 2012

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    Category 5 (C5) Super Typhoon Bopha, the world’s worst storm of 2012, formed abnormally close to the West Pacific Equator, and Bopha’s Mindanao landfall has the record equatorial proximity for C5 storms. Bopha generated a debris flow that buried 500 ha of New Bataan municipality and killed 566 people. New Bataan, established in 1968, had never experienced super typhoons and debris flows. We describe the respective histories of New Bataan and Super Typhoon Bopha; debris flows; and how population growth and unwise settlement practices contribute to Philippine “natural” disasters. The historical record of Mindanao tropical cyclones yields clues regarding how climate change may be exacerbating near-equatorial vulnerability to typhoons. Existing models of future typhoon behavior do not apply well to Mindanao because they evaluate only the tropical cyclones that occur during the main June–October typhoon season, and most Mindanao tropical cyclones occur in the off season. The models also ignore tropical depressions, the most frequent—and commonly lethal—Mindanao cyclones. Including these in annual tallies of Mindanao cyclones up to early 2018 reveals a pronounced and accelerating increase since 1990. Mindanao is susceptible to other natural hazards, including other consequences of climate change and volcanic activity

    MMP-12, Secreted by Pro-Inflammatory Macrophages, Targets Endoglin in Human Macrophages and Endothelial Cells

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    Upon inflammation, monocyte-derived macrophages (MF) infiltrate blood vessels to regulate several processes involved in vascular pathophysiology. However, little is known about the mediators involved. Macrophage polarization is crucial for a fast and e cient initial response (GM-MF) and a good resolution (M-MF) of the inflammatory process. The functional activity of polarized MF is exerted mainly through their secretome, which can target other cell types, including endothelial cells. Endoglin (CD105) is a cell surface receptor expressed by endothelial cells and MF that is markedly upregulated in inflammation and critically involved in angiogenesis. In addition, a soluble form of endoglin with anti-angiogenic activity has been described in inflammation-associated pathologies. The aim of this work was to identify components of the MF secretome involved in the shedding of soluble endoglin. We find that the GM-MF secretome contains metalloprotease 12 (MMP-12), a GM-MF specific marker that may account for the anti-angiogenic activity of the GM-MF secretome. Cell surface endoglin is present in both GM-MF and M-MF, but soluble endoglin is only detected in GM-MF culture supernatants. Moreover, MMP-12 is responsible for the shedding of soluble endoglin in vitro and in vivo by targeting membrane-bound endoglin in both MF and endothelial cells. These data demonstrate a direct correlation between GM-MF polarization, MMP-12, and soluble endoglin expression and function. By targeting endothelial cells, MMP-12 may represent a novel mediator involved in vascular homeostasis.Ministerio de Ciencia, Innovación y Universidades of Spain (SAF2013-43421-R to C.B.; SAF2017-83785-R and SAF2014-23801 to A.L.C.)Consejo Superior de Investigaciones Cientificas (201920E022 to C.B.)Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER; ISCIII-CB06/07/0038 to C.B.)Czech Republic Specific University Research (SVV-260414 to P.N.)CIBERER is an initiative of the Instituto de Salud Carlos III (ISCIII) of Spain supported by FEDER fundsM.A. was funded with a fellowship from Ministerio de Ciencia e Innovación (BES-2008-003888)M.V. was supported by a short-term mobility fellowship from the European Erasmus Programm

    Exploring the components, asymmetry and distribution of relationship quality in wild Barbary macaques (Macaca sylvanus)

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    Social relationships between group members are a key feature of many animal societies. The quality of social relationships has been described by three main components: value, compatibility and security, based on the benefits, tenure and stability of social exchanges. We aimed to analyse whether this three component structure could be used to describe the quality of social relationships in wild Barbary macaques (Macaca sylvanus). Moreover, we examined whether relationship quality was affected by the sex, age and rank differences between social partners, and investigated the asymmetric nature of social relationships. We collected over 1,900 hours of focal data on seven behavioural variables measuring relationship quality, and used principal component analysis to investigate how these variables clustered together. We found that relationship quality in wild Barbary macaques can be described by a three component structure that represents the value, compatibility and security of a relationship. Female-female dyads had more valuable relationships and same-age dyads more compatible relationships than any other dyad. Rank difference had no effect on the quality of a social relationship. Finally, we found a high degree of asymmetry in how members of a dyad exchange social behaviour. We argue that the asymmetry of social relationships should be taken into account when exploring the pattern and function of social behaviour in animal societies

    Beyond property: Rural politics and land-use change in the Colombian sugarcane landscape

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    Analysing the sugarcane landscape in the flat valley of the Cauca River (Colombia) reveals that agricultural industrialization in the region required the concentration of land use by regional industrialists and the corresponding exclusion of landowners and poor peasants from territorial decision-making processes. The analytical lens used in this article, based on the use and control over land and land-based natural commons, allows for the characterization of three periods in a non-linear process of articulation and dispute between poor peasant and capitalist agents in the expansion of the sugarcane monoculture during the 20th century. The different constellations of social agents, governmental nexus, and capital enclosures have enacted through mechanisms that, beyond concentrating land property, have managed to deprive rural ethnic communities from their cultural and environmental heritage, traditional economies, and possible futures.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151270/1/joac12332_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151270/2/joac12332.pd
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