334 research outputs found
Synthesis of a Unique Psammaplysin F Library and Functional Evaluation in Prostate Cancer Cells by Multiparametric Quantitative Single Cell Imaging
No full textThe spirooxepinisoxazoline alkaloid psammaplysin F (1) was selected as a scaffold for the generation of a unique screening library for both drug discovery and chemical biology research. Large-scale extraction and isolation chemistry was performed on a marine sponge (Hyattella sp.) collected from the Great Barrier Reef in order to acquire >200 mg of the desired bromotyrosine-derived alkaloidal scaffold. Parallel solution-phase semisynthesis was employed to generate a series of psammaplysin-based urea (2–9) and amide analogues (10–11) in low to moderate yields. The chemical structures of all analogues were characterized using NMR and MS data. The absolute configuration of psammaplysin F and all semisynthetic analogues was determined as 6R, 7R by comparison of ECD data with literature values. All compounds (1–11) were evaluated for their effect on cell cycle distribution and changes to cancer metabolism in LNCaP prostate cancer cells using a multiparametric quantitative single-cell imaging approach. These investigations identified that in LNCaP cells psammaplysin F and some urea analogues caused loss of mitochondrial membrane potential, fragmentation of the mitochondrial tubular network, chromosome misalignment, and cell cycle arrest in mitosis.Full Tex
Data and code associated with "Generative Models of Multi-channel Data Based on a Single Example - Application to Dust Emission"
No full textData and code associated with: Régaldo-Saint Blancard, B., Allys, E., Auclair, C., Boulanger, F., Eickenberg, M., Levrier, F., Vacher, L. & Zhang, S. ; "Generative Models of Multi-channel Data Based on a Single Example - Application to Dust Emission" ; arXiv:2208.0353
Velocity centroids and the structure of interstellar turbulence
No full textWe present an analytical study of the statistical properties of integrated emission and velocity centroids for a slightly compressible turbulent slab model, to retrieve the underlying statistics of three-dimensional density and velocity fluctuations. Under the assumptions that the density and velocity fields are homogeneous and isotropic, we derive the expressions of the antenna temperature for an optically thin spectral line observation, and of its successive moments with respect to the line of sight velocity component, focusing on the zeroth (intensity or integrated emission I) and first (non-normalized velocity centroid C) moments. The ratio of the latter to the former is the normalized centroid C0, whose expression can be linearized for small density fluctuations. To describe the statistics of I, C and C0, we derive expansions of their autocorrelation functions in powers of density fluctuations and perform a lowest-order real-space calculation of their scaling behaviour, assuming that the density and velocity fields are fractional Brownian motions. We hence confirm, within the scope of this study, the property recently found numerically by [CITE] that the spectral index of the normalized centroid is equal to that of the full velocity field. However, it is also argued that, in order to retrieve the velocity statistics, normalization of centroids may actually not be the best way to remove the influence of density fluctuations. In this respect, we discuss the modified velocity centroids introduced by [CITE] as a possible alternative. In a following paper, we shall present numerical studies aimed at assessing the validity domain of these results
Toxicarioside M, a new cytotoxic 10β-hydroxy-19-nor-cardenolide from Antiaris toxicaria
No full textA new 10β-hydroxy-19-nor-cardenolide, named toxicarioside M (1), was isolated from the trunk bark of Antiaris toxicaria (Pers.) Lesch (Moraceae), along with six known cardenolides (convallatoxin (2), convallatoxol (3), convalloside (4), 3-O-ß-D-xylopyranosylstrophanthidin (5), glucostrophanthidin (6) and strophanthidin (7)). Their structures were elucidated on the basis of HR-MS n analysis, spectroscopic methods (IR, UV, 1D and 2D NMR) and by comparison with data reported in the literature. The cardenolides were evaluated for their cytotoxic activity against KB, HCT-116, SF-268, MCF-7, HL-60, PC-3 and MRC-5 cell lines. © 2012 Elsevier B.V. All rights reserved
The Pathway Between Art and Science: One Painter's Metaphorical Journey
No full text The author describes his un-derstanding of the place and pur-pose of his art in the context of our late twentieth century: as an artist, he does not accept a place in the current “death of art” situa-tion. He agrees that abstract art is not self-explanatory although its meaning exists in the collective unconscious. To explain his effort, he has found metaphors in quan-tum physics that enable him to link his artistic process to the dy-namics of progress found in sci-ence rather than to those of re-gression found in the arts. </jats:p
PANDORÆ : Retrieving, curating and exploring enhanced corpuses through time and space
No full textInternational audiencePANDORÆ : Retrieving, curating and exploring enhanced corpi through time and space Mapping the state of research in a particular field has been made easier through commercial services providing API-based bibliometric-enhanced corpuses retrieval. Common assertions such as “the use of CRISPR technologies has skyrocketed in laboratories all around the world since 2012” can now be easily verified in both quantitative and qualitative perspectives using those platforms. Such services as Elsevier’s Scopus propose inbuilt functions to explore corpuses chronologically and geographically. They don’t, however, allow for hand curation and enrichment of the corpus. This lecture advocates for a solution to this methodological issue using PANDORÆ, a free and open source software designed for that purpose. PANDORÆ requests corpuses from the Scopus API, enriches its data by geolocating each document’s affiliations, and then uploads the resulting dataset to a Zotero library. The user is then free to curate the corpus, adding, editing or removing items. PANDORÆ allows downloading it back from Zotero to its internal databases, and to display the enriched corpuses on a map, on a timeline, or as an author-directed force-layout network graph.This presentation will also introduce more advanced PANDORAE features, such as displaying Twitter dataset obtained through Gazouilloire, mapping web entities loaded from Hyphe and scraping biorXiv results using Artoo
Planck 2018 results: II. Low frequency instrument data processing
No full textCSIC, MINECO, JA, and RES (Spain); ERC and PRACE (EU) (...)Akrami, Y., Argüeso, F., Ashdown, M., Aumont, J., Baccigalupi, C., Ballardini, M., Banday, A.J., Barreiro, R.B., Bartolo, N., Basak, S., Benabed, K., Bernard, J.-P., Bersanelli, M., Bielewicz, P., Bonavera, L., Bond, J.R., Borrill, J., Bouchet, F.R., Boulanger, F., Bucher, M., Burigana, C., Butler, R.C., Calabrese, E., Cardoso, J.-F., Colombo, L.P.L., Crill, B.P., Cuttaia, F., De Bernardis, P., De Rosa, A., De Zotti, G., Delabrouille, J., Di Valentino, E., Dickinson, C., Diego, J.M., Donzelli, S., Ducout, A., Dupac, X., Efstathiou, G., Elsner, F., Enßlin, T.A., Eriksen, H.K., Fantaye, Y., Finelli, F., Frailis, M., Franceschi, E., Frolov, A., Galeotta, S., Galli, S., Ganga, K., Génova-Santos, R.T., Gerbino, M., Ghosh, T., González-Nuevo, J., Górski, K.M., Gratton, S., Gruppuso, A., Gudmundsson, J.E., Handley, W., Hansen, F.K., Herranz, D., Hivon, E., Huang, Z., Jaffe, A.H., Jones, W.C., Karakci, A., Keihänen, E., Keskitalo, R., Kiiveri, K., Kim, J., Kisner, T.S., Krachmalnicoff, N., Kunz, M., Kurki-Suonio, H., Lamarre, J.-M., Lasenby, A., Lattanzi, M., Lawrence, C.R., Leahy, J.P., Levrier, F., Liguori, M., Lilje, P.B., Lindholm, V., López-Caniego, M., Ma, Y.-Z., Maciás-Pérez, J.F., Maggio, G., Maino, D., Mandolesi, N., Mangilli, A., Maris, M., Martin, P.G., Martínez-González, E., Matarrese, S., Mauri, N., McEwen, J.D., Meinhold, P.R., Melchiorri, A., Mennella, A., Migliaccio, M., Molinari, D., Montier, L., Morgante, G., Moss, A., Natoli, P., Pagano, L., Paoletti, D., Partridge, B., Patanchon, G., Patrizii, L., Peel, M., Perrotta, F., Pettorino, V., Piacentini, F., Polenta, G., Puget, J.-L., Rachen, J.P., Racine, B., Reinecke, M., Remazeilles, M., Renzi, A., Rocha, G., Roudier, G., Rubiño-Martín, J.A., Salvati, L., Sandri, M., Savelainen, M., Scott, D., Seljebotn, D.S., Sirignano, C., Sirri, G., Spencer, L.D., Suur-Uski, A.-S., Tauber, J.A., Tavagnacco, D., Tenti, M., Terenzi, L., Toffolatti, L., Tomasi, M., Trombetti, T., Valiviita, J., Vansyngel, F., Van Tent, B., Vielva, P., Villa, F., Vittorio, N., Wandelt, B.D., Watson, R., Wehus, I.K., Zacchei, A., Zonca, A
A novel estimator of the polarization amplitude from normally distributed Stokes parameters
No full textWe propose a novel estimator of the polarization amplitude from a single measurement of its normally distributed Stokes components. Based on the properties of the Rice distribution and dubbed "MAS" (Modified ASymptotic), it meets several desirable criteria:(i) its values lie in the whole positive region; (ii) its distribution is continuous; (iii) it transforms smoothly with the signal-to-noise ratio (SNR) from a Rayleigh-like shape to a Gaussian one ; (iv) it is unbiased and reaches its components variance as soon as the SNR exceeds 2; (v) it is analytic and can therefore be used on large data-sets. We also revisit the construction of its associated confidence intervals, and show how the Feldman-Cousins prescription efficiently solves the issue of classical intervals lying entirely in the unphysical negative domain. Such intervals can be used to identify statistically significant polarized regions and conversely build masks for polarization data. We then consider the case of a general covariance matrix and perform a generalization of the estimator that preserves its asymptotic properties. We show that its bias does not depend on the true polarization angle, and provide an analytic estimate of its variance. The estimator value, together with its variance, provide a powerful point-estimate of the true polarization amplitude that follows an unbiased Gaussian distribution for an SNR as low as 2. These results can be applied to the much more general case of transforming any normally distributed random variable from Cartesian to polar coordinates
Planck 2018 results: IX. Constraints on primordial non-Gaussianity
No full textCSIC, MINECO, JA, and RES (Spain); ERC and PRACE (EU) (...)Akrami, Y., Arroja, F., Ashdown, M., Aumont, J., Baccigalupi, C., Ballardini, M., Banday, A.J., Barreiro, R.B., Bartolo, N., Basak, S., Benabed, K., Bernard, J.-P., Bersanelli, M., Bielewicz, P., Bond, J.R., Borrill, J., Bouchet, F.R., Bucher, M., Burigana, C., Butler, R.C., Calabrese, E., Cardoso, J.-F., Casaponsa, B., Challinor, A., Chiang, H.C., Colombo, L.P.L., Combet, C., Crill, B.P., Cuttaia, F., De Bernardis, P., De Rosa, A., De Zotti, G., Delabrouille, J., Delouis, J.-M., Di Valentino, E., Diego, J.M., Doré, O., Douspis, M., Ducout, A., Dupac, X., Dusini, S., Efstathiou, G., Elsner, F., Enßlin, T.A., Eriksen, H.K., Fantaye, Y., Fergusson, J., Fernandez-Cobos, R., Finelli, F., Frailis, M., Fraisse, A.A., Franceschi, E., Frolov, A., Galeotta, S., Galli, S., Ganga, K., Génova-Santos, R.T., Gerbino, M., González-Nuevo, J., Górski, K.M., Gratton, S., Gruppuso, A., Gudmundsson, J.E., Hamann, J., Handley, W., Hansen, F.K., Herranz, D., Hivon, E., Huang, Z., Jaffe, A.H., Jones, W.C., Jung, G., Keihänen, E., Keskitalo, R., Kiiveri, K., Kim, J., Krachmalnicoff, N., Kunz, M., Kurki-Suonio, H., Lamarre, J.-M., Lasenby, A., Lattanzi, M., Lawrence, C.R., Le Jeune, M., Levrier, F., Lewis, A., Liguori, M., Lilje, P.B., Lindholm, V., López-Caniego, M., Ma, Y.-Z., Maciás-Pérez, J.F., Maggio, G., Maino, D., Mandolesi, N., Marcos-Caballero, A., Maris, M., Martin, P.G., Martínez-González, E., Matarrese, S., Mauri, N., McEwen, J.D., Meerburg, P.D., Meinhold, P.R., Melchiorri, A., Mennella, A., Migliaccio, M., Miville-Deschênes, M.-A., Molinari, D., Moneti, A., Montier, L., Morgante, G., Moss, A., Münchmeyer, M., Natoli, P., Oppizzi, F., Pagano, L., Paoletti, D., Partridge, B., Patanchon, G., Perrotta, F., Pettorino, V., Piacentini, F., Polenta, G., Puget, J.-L., Rachen, J.P., Racine, B., Reinecke, M., Remazeilles, M., Renzi, A., Rocha, G., Rubiño-Martín, J.A., Ruiz-Granados, B., Salvati, L., Savelainen, M., Scott, D., Shellard, E.P.S., Shiraishi, M., Sirignano, C., Sirri, G., Smith, K., Spencer, L.D., Stanco, L., Sunyaev, R., Suur-Uski, A.-S., Tauber, J.A., Tavagnacco, D., Tenti, M., Toffolatti, L., Tomasi, M., Trombetti, T., Valiviita, J., Van Tent, B., Vielva, P., Villa, F., Vittorio, N., Wandelt, B.D., Wehus, I.K., Zacchei, A., Zonca, A
Fourier phase analysis in radio-interferometry
No full textMost statistical tools used to characterize the complex structures of the interstellar medium can be related to the power spectrum, and therefore to the Fourier amplitudes of the observed fields. To tap into the vast amount of information contained in the Fourier phases, one may consider the probability distribution function (PDF) of phase increments, and the related concepts of phase entropy and phase structure quantity. We use these ideas here with the purpose of assessing the ability of radio-interferometers to detect and recover this information. By comparing current arrays such as the VLA and Plateau de Bure to the future ALMA instrument, we show that the latter is definitely needed to achieve significant detection of phase structure, and that it will do so even in the presence of a fair amount of atmospheric phase fluctuations. We also show that ALMA will be able to recover the actual “amount” of phase structure in the noise-free case, if multiple configurations are used
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