Equations of Motion of Spinning Relativistic Particle in Electromagnetic and Gravitational Fields

We consider the motion of a spinning relativistic particle in external electromagnetic and gravitational fields, to first order in the external field, but to an arbitrary order in spin. The noncovariant spin formalism is crucial for the correct description of the influence of the spin on the particle trajectory. We show that the true coordinate of a relativistic spinning particle is its naive, common coordinate \r. Concrete calculations are performed up to second order in spin included. A simple derivation is presented for the gravitational spin-orbit and spin-spin interactions of a relativistic particle. We discuss the gravimagnetic moment (GM), a specific spin effect in general relativity. It is shown that for the Kerr black hole the gravimagnetic ratio, i.e., the coefficient at the GM, equals unity (just as for the charged Kerr hole the gyromagnetic ratio equals two). The equations of motion obtained for relativistic spinning particle in external gravitational field differ essentially from the Papapetrou equations.Comment: 32 pages, latex, Plenary talk at the Fairbank Meeting on the Lense--Thirring Effect, Rome-Pescara, 29/6-4/7 199

Simulating magnetized neutron stars with discontinuous Galerkin methods

Discontinuous Galerkin methods are popular because they can achieve high order where the solution is smooth, because they can capture shocks while needing only nearest-neighbor communication, and because they are relatively easy to formulate on complex meshes. We perform a detailed comparison of various limiting strategies presented in the literature applied to the equations of general relativistic magnetohydrodynamics. We compare the standard minmod/$\Lambda\Pi^N$ limiter, the hierarchical limiter of Krivodonova, the simple WENO limiter, the HWENO limiter, and a discontinuous Galerkin-finite-difference hybrid method. The ultimate goal is to understand what limiting strategies are able to robustly simulate magnetized TOV stars without any fine-tuning of parameters. Among the limiters explored here, the only limiting strategy we can endorse is a discontinuous Galerkin-finite-difference hybrid method

Gene Regulation and Epigenetic Remodeling in Murine Embryonic Stem Cells by c-Myc

BACKGROUND:The Myc oncoprotein, a transcriptional regulator involved in the etiology of many different tumor types, has been demonstrated to play an important role in the functions of embryonic stem (ES) cells. Nonetheless, it is still unclear as to whether Myc has unique target and functions in ES cells. METHODOLOGY/PRINCIPAL FINDINGS:To elucidate the role of c-Myc in murine ES cells, we mapped its genomic binding sites by chromatin-immunoprecipitation combined with DNA microarrays (ChIP-chip). In addition to previously identified targets we identified genes involved in pluripotency, early development, and chromatin modification/structure that are bound and regulated by c-Myc in murine ES cells. Myc also binds and regulates loci previously identified as Polycomb (PcG) targets, including genes that contain bivalent chromatin domains. To determine whether c-Myc influences the epigenetic state of Myc-bound genes, we assessed the patterns of trimethylation of histone H3-K4 and H3-K27 in mES cells containing normal, increased, and reduced levels of c-Myc. Our analysis reveals widespread and surprisingly diverse changes in repressive and activating histone methylation marks both proximal and distal to Myc binding sites. Furthermore, analysis of bulk chromatin from phenotypically normal c-myc null E7 embryos demonstrates a 70-80% decrease in H3-K4me3, with little change in H3-K27me3, compared to wild-type embryos indicating that Myc is required to maintain normal levels of histone methylation. CONCLUSIONS/SIGNIFICANCE:We show that Myc induces widespread and diverse changes in histone methylation in ES cells. We postulate that these changes are indirect effects of Myc mediated by its regulation of target genes involved in chromatin remodeling. We further show that a subset of PcG-bound genes with bivalent histone methylation patterns are bound and regulated in response to altered c-Myc levels. Our data indicate that in mES cells c-Myc binds, regulates, and influences the histone modification patterns of genes involved in chromatin remodeling, pluripotency, and differentiation

One thousand plant transcriptomes and the phylogenomics of green plants

Abstract: Green plants (Viridiplantae) include around 450,000–500,000 species1, 2 of great diversity and have important roles in terrestrial and aquatic ecosystems. Here, as part of the One Thousand Plant Transcriptomes Initiative, we sequenced the vegetative transcriptomes of 1,124 species that span the diversity of plants in a broad sense (Archaeplastida), including green plants (Viridiplantae), glaucophytes (Glaucophyta) and red algae (Rhodophyta). Our analysis provides a robust phylogenomic framework for examining the evolution of green plants. Most inferred species relationships are well supported across multiple species tree and supermatrix analyses, but discordance among plastid and nuclear gene trees at a few important nodes highlights the complexity of plant genome evolution, including polyploidy, periods of rapid speciation, and extinction. Incomplete sorting of ancestral variation, polyploidization and massive expansions of gene families punctuate the evolutionary history of green plants. Notably, we find that large expansions of gene families preceded the origins of green plants, land plants and vascular plants, whereas whole-genome duplications are inferred to have occurred repeatedly throughout the evolution of flowering plants and ferns. The increasing availability of high-quality plant genome sequences and advances in functional genomics are enabling research on genome evolution across the green tree of life

Tests of General Relativity with GW150914

The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large-velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in general relativity. We find that the final remnant’s mass and spin, as determined from the low-frequency (inspiral) and high-frequency (postinspiral) phases of the signal, are mutually consistent with the binary black-hole solution in general relativity. Furthermore, the data following the peak of GW150914 are consistent with the least-damped quasinormal mode inferred from the mass and spin of the remnant black hole. By using waveform models that allow for parametrized general-relativity violations during the inspiral and merger phases, we perform quantitative tests on the gravitational-wave phase in the dynamical regime and we determine the first empirical bounds on several high-order post-Newtonian coefficients. We constrain the graviton Compton wavelength, assuming that gravitons are dispersed in vacuum in the same way as particles with mass, obtaining a 90%-confidence lower bound of 1013  km. In conclusion, within our statistical uncertainties, we find no evidence for violations of general relativity in the genuinely strong-field regime of gravity

Effects of waveform model systematics on the interpretation of GW150914

PAPER Effects of waveform model systematics on the interpretation of GW150914 B P Abbott1, R Abbott1, T D Abbott2, M R Abernathy3, F Acernese4,5, K Ackley6, C Adams7, T Adams8, P Addesso9,144, R X Adhikari1, V B Adya10, C Affeldt10, M Agathos11, K Agatsuma11, N Aggarwal12, O D Aguiar13, L Aiello14,15, A Ain16, P Ajith17, B Allen10,18,19, A Allocca20,21, P A Altin22, A Ananyeva1, S B Anderson1, W G Anderson18, S Appert1, K Arai1, M C Araya1, J S Areeda23, N Arnaud24, K G Arun25, S Ascenzi15,26, G Ashton10, M Ast27, S M Aston7, P Astone28, P Aufmuth19, C Aulbert10, A Avila-Alvarez23, S Babak29, P Bacon30, M K M Bader11, P T Baker31, F Baldaccini32,33, G Ballardin34, S W Ballmer35, J C Barayoga1, S E Barclay36, B C Barish1, D Barker37, F Barone4,5, B Barr36, L Barsotti12, M Barsuglia30, D Barta38, J Bartlett37, I Bartos39, R Bassiri40, A Basti20,21, J C Batch37, C Baune10, V Bavigadda34, M Bazzan41,42, C Beer10, M Bejger43, I Belahcene24, M Belgin44, A S Bell36, B K Berger1, G Bergmann10, C P L Berry45, D Bersanetti46,47, A Bertolini11, J Betzwieser7, S Bhagwat35, R Bhandare48, I A Bilenko49, G Billingsley1, C R Billman6, J Birch7, R Birney50, O Birnholtz10, S Biscans1,12, A Bisht19, M Bitossi34, C Biwer35, M A Bizouard24, J K Blackburn1, J Blackman51, C D Blair52, D G Blair52, R M Blair37, S Bloemen53, O Bock10, M Boer54, G Bogaert54, A Bohe29, F Bondu55, R Bonnand8, B A Boom11, R Bork1, V Boschi20,21, S Bose16,56, Y Bouffanais30, A Bozzi34, C Bradaschia21, P R Brady18, V B Braginsky49,145, M Branchesi57,58, J E Brau59, T Briant60, A Brillet54, M Brinkmann10, V Brisson24, P Brockill18, J E Broida61, A F Brooks1, D A Brown35, D D Brown45, N M Brown12, S Brunett1, C C Buchanan2, A Buikema12, T Bulik62, H J Bulten11,63, A Buonanno29,64, D Buskulic8, C Buy30, R L Byer40, M Cabero10, L Cadonati44, G Cagnoli65,66, C Cahillane1, J Calderón Bustillo44, T A Callister1, E Calloni5,67, J B Camp68, K C Cannon69, H Cao70, J Cao71, C D Capano10, E Capocasa30, F Carbognani34, S Caride72, J Casanueva Diaz24, C Casentini15,26, S Caudill18, M Cavaglià73, F Cavalier24, R Cavalieri34, G Cella21, C B Cepeda1, L Cerboni Baiardi57,58, G Cerretani20,21, E Cesarini15,26, S J Chamberlin74, M Chan36, S Chao75, P Charlton76, E Chassande-Mottin30, B D Cheeseboro31, H Y Chen77, Y Chen51, H-P Cheng6, A Chincarini47, A Chiummo34, T Chmiel78, H S Cho79, M Cho64, J H Chow22, N Christensen61, Q Chu52, A J K Chua80, S Chua60, S Chung52, G Ciani6, F Clara37, J A Clark44, F Cleva54, C Cocchieri73, E Coccia14,15, P-F Cohadon60, A Colla28,81, C G Collette82, L Cominsky83, M Constancio Jr13, L Conti42, S J Cooper45, T R Corbitt2, N Cornish84, A Corsi72, S Cortese34, C A Costa13, M W Coughlin61, S B Coughlin85, J-P Coulon54, S T Countryman39, P Couvares1, P B Covas86, E E Cowan44, D M Coward52, M J Cowart7, D C Coyne1, R Coyne72, J D E Creighton18, T D Creighton87, J Cripe2, S G Crowder88, T J Cullen23, A Cumming36, L Cunningham36, E Cuoco34, T Dal Canton68, S L Danilishin36, S D'Antonio15, K Danzmann10,19, A Dasgupta89, C F Da Silva Costa6, V Dattilo34, I Dave48, M Davier24, G S Davies36, D Davis35, E J Daw90, B Day44, R Day34, S De35, D DeBra40, G Debreczeni38, J Degallaix65, M De Laurentis5,67, S Deléglise60, W Del Pozzo45, T Denker10, T Dent10, V Dergachev29, R De Rosa5,67, R T DeRosa7, R DeSalvo91, J Devenson50, R C Devine31, S Dhurandhar16, M C Díaz87, L Di Fiore5, M Di Giovanni92,93, T Di Girolamo5,67, A Di Lieto20,21, S Di Pace28,81, I Di Palma28,29,81, A Di Virgilio21, Z Doctor77, V Dolique65, F Donovan12, K L Dooley73, S Doravari10, I Dorrington94, R Douglas36, M Dovale Álvarez45, T P Downes18, M Drago10, R W P Drever1,146, J C Driggers37, Z Du71, M Ducrot8, S E Dwyer37, T B Edo90, M C Edwards61, A Effler7, H-B Eggenstein10, P Ehrens1, J Eichholz1, S S Eikenberry6, R A Eisenstein12, R C Essick12, Z Etienne31, T Etzel1, M Evans12, T M Evans7, R Everett74, M Factourovich39, V Fafone14,15,26, H Fair35, S Fairhurst94, X Fan71, S Farinon47, B Farr77, W M Farr45, E J Fauchon-Jones94, M Favata95, M Fays94, H Fehrmann10, M M Fejer40, A Fernández Galiana12, I Ferrante20,21, E C Ferreira13, F Ferrini34, F Fidecaro20,21, I Fiori34, D Fiorucci30, R P Fisher35, R Flaminio65,96, M Fletcher36, H Fong97, S S Forsyth44, J-D Fournier54, S Frasca28,81, F Frasconi21, Z Frei98, A Freise45, R Frey59, V Frey24, E M Fries1, P Fritschel12, V V Frolov7, P Fulda6,68, M Fyffe7, H Gabbard10, B U Gadre16, S M Gaebel45, J R Gair99, L Gammaitoni32, S G Gaonkar16, F Garufi5,67, G Gaur100, V Gayathri101, N Gehrels68, G Gemme47, E Genin34, A Gennai21, J George48, L Gergely102, V Germain8, S Ghonge17, Abhirup Ghosh17, Archisman Ghosh11,17, S Ghosh11,53, J A Giaime2,7, K D Giardina7, A Giazotto21, K Gill103, A Glaefke36, E Goetz10, R Goetz6, L Gondan98, G González2, J M Gonzalez Castro20,21, A Gopakumar104, M L Gorodetsky49, S E Gossan1, M Gosselin34, R Gouaty8, A Grado5,105, C Graef36, M Granata65, A Grant36, S Gras12, C Gray37, G Greco57,58, A C Green45, P Groot53, H Grote10, S Grunewald29, G M Guidi57,58, X Guo71, A Gupta16, M K Gupta89, K E Gushwa1, E K Gustafson1, R Gustafson106, J J Hacker23, B R Hall56, E D Hall1, G Hammond36, M Haney104, M M Hanke10, J Hanks37, C Hanna74, M D Hannam94, J Hanson7, T Hardwick2, J Harms57,58, G M Harry3, I W Harry29, M J Hart36, M T Hartman6, C-J Haster45,97, K Haughian36, J Healy107, A Heidmann60, M C Heintze7, H Heitmann54, P Hello24, G Hemming34, M Hendry36, I S Heng36, J Hennig36, J Henry107, A W Heptonstall1, M Heurs10,19, S Hild36, D Hoak34, D Hofman65, K Holt7, D E Holz77, P Hopkins94, J Hough36, E A Houston36, E J Howell52, Y M Hu10, E A Huerta108, D Huet24, B Hughey103, S Husa86, S H Huttner36, T Huynh-Dinh7, N Indik10, D R Ingram37, R Inta72, H N Isa36, J-M Isac60, M Isi1, T Isogai12, B R Iyer17, K Izumi37, T Jacqmin60, K Jani44, P Jaranowski109, S Jawahar110, F Jiménez-Forteza86, W W Johnson2, D I Jones111, R Jones36, R J G Jonker11, L Ju52, J Junker10, C V Kalaghatgi94, V Kalogera85, S Kandhasamy73, G Kang79, J B Kanner1, S Karki59, K S Karvinen10, M Kasprzack2, E Katsavounidis12, W Katzman7, S Kaufer19, T Kaur52, K Kawabe37, F Kéfélian54, D Keitel86, D B Kelley35, R Kennedy90, J S Key112, F Y Khalili49, I Khan14, S Khan94, Z Khan89, E A Khazanov113, N Kijbunchoo37, Chunglee Kim114, J C Kim115, Whansun Kim116, W Kim70, Y-M Kim114,117, S J Kimbrell44, E J King70, P J King37, R Kirchhoff10, J S Kissel37, B Klein85, L Kleybolte27, S Klimenko6, P Koch10, S M Koehlenbeck10, S Koley11, V Kondrashov1, A Kontos12, M Korobko27, W Z Korth1, I Kowalska62, D B Kozak1, C Krämer10, V Kringel10, B Krishnan10, A Królak118,119, G Kuehn10, P Kumar97, R Kumar89, L Kuo75, A Kutynia118, B D Lackey29,35, M Landry37, R N Lang18, J Lange107, B Lantz40, R K Lanza12, A Lartaux-Vollard24, P D Lasky120, M Laxen7, A Lazzarini1, C Lazzaro42, P Leaci28,81, S Leavey36, E O Lebigot30, C H Lee117, H K Lee121, H M Lee114, K Lee36, J Lehmann10, A Lenon31, M Leonardi92,93, J R Leong10, N Leroy24, N Letendre8, Y Levin120, T G F Li122, A Libson12, T B Littenberg123, J Liu52, N A Lockerbie110, A L Lombardi44, L T London94, J E Lord35, M Lorenzini14,15, V Loriette124, M Lormand7, G Losurdo21, J D Lough10,19, G Lovelace23, H Lück10,19, A P Lundgren10, R Lynch12, Y Ma51, S Macfoy50, B Machenschalk10, M MacInnis12, D M Macleod2, F Magaña-Sandoval35, E Majorana28, I Maksimovic124, V Malvezzi15,26, N Man54, V Mandic125, V Mangano36, G L Mansell22, M Manske18, M Mantovani34, F Marchesoni33,126, F Marion8, S Márka39, Z Márka39, A S Markosyan40, E Maros1, F Martelli57,58, L Martellini54, I W Martin36, D V Martynov12, K Mason12, A Masserot8, T J Massinger1, M Masso-Reid36, S Mastrogiovanni28,81, F Matichard1,12, L Matone39, N Mavalvala12, N Mazumder56, R McCarthy37, D E McClelland22, S McCormick7, C McGrath18, S C McGuire127, G McIntyre1, J McIver1, D J McManus22, T McRae22, S T McWilliams31, D Meacher54,74, G D Meadors10,29, J Meidam11, A Melatos128, G Mendell37, D Mendoza-Gandara10, R A Mercer18, E L Merilh37, M Merzougui54, S Meshkov1, C Messenger36, C Messick74, R Metzdorff60, P M Meyers125, F Mezzani28,81, H Miao45, C Michel65, H Middleton45, E E Mikhailov129, L Milano5,67, A L Miller6,28,81, A Miller85, B B Miller85, J Miller12, M Millhouse84, Y Minenkov15, J Ming29, S Mirshekari130, C Mishra17, S Mitra16, V P Mitrofanov49, G Mitselmakher6, R Mittleman12, A Moggi21, M Mohan34, S R P Mohapatra12, M Montani57,58, B C Moore95, C J Moore80, D Moraru37, G Moreno37, S R Morriss87, B Mours8, C M Mow-Lowry45, G Mueller6, A W Muir94, Arunava Mukherjee17, D Mukherjee18, S Mukherjee87, N Mukund16, A Mullavey7, J Munch70, E A M Muniz23, P G Murray36, A Mytidis6, K Napier44, I Nardecchia15,26, L Naticchioni28,81, G Nelemans11,53, T J N Nelson7, M Neri46,47, M Nery10, A Neunzert106, J M Newport3, G Newton36, T T Nguyen22, A B Nielsen10, S Nissanke11,53, A Nitz10, A Noack10, F Nocera34, D Nolting7, M E N Normandin87, L K Nuttall35, J Oberling37, E Ochsner18, E Oelker12, G H Ogin131, J J Oh116, S H Oh116, F Ohme10,94, M Oliver86, P Oppermann10, Richard J Oram7, B O'Reilly7, R O'Shaughnessy107, D J Ottaway70, H Overmier7, B J Owen72, A E Pace74, J Page123, A Pai101, S A Pai48, J R Palamos59, O Palashov113, C Palomba28, A Pal-Singh27, H Pan75, C Pankow85, F Pannarale94, B C Pant48, F Paoletti21,34, A Paoli34, M A Papa10,18,29, H R Paris40, W Parker7, D Pascucci36, A Pasqualetti34, R Passaquieti20,21, D Passuello21, B Patricelli20,21, B L Pearlstone36, M Pedraza1, R Pedurand65,132, L Pekowsky35, A Pele7, S Penn133, C J Perez37, A Perreca1, L M Perri85, H P Pfeiffer97, M Phelps36, O J Piccinni28,81, M Pichot54, F Piergiovanni57,58, V Pierro9, G Pillant34, L Pinard65, I M Pinto9, M Pitkin36, M Poe18, R Poggiani20,21, P Popolizio34, A Post10, J Powell36, J Prasad16, J W W Pratt103, V Predoi94, T Prestegard18,125, M Prijatelj10,34, M Principe9, S Privitera29, G A Prodi92,93, L G Prokhorov49, O Puncken10, M Punturo33, P Puppo28, M Pürrer29, H Qi18, J Qin52, S Qiu120, V Quetschke87, E A Quintero1, R Quitzow-James59, F J Raab37, D S Rabeling22, H Radkins37, P Raffai98, S Raja48, C Rajan48, M Rakhmanov87, P Rapagnani28,81, V Raymond29, M Razzano20,21, V Re26, J Read23, T Regimbau54, L Rei47, S Reid50, D H Reitze1,6, H Rew129, S D Reyes35, E Rhoades103, F Ricci28,81, K Riles106, M Rizzo107, N A Robertson1,36, R Robie36, F Robinet24, A Rocchi15, L Rolland8, J G Rollins1, V J Roma59, J D Romano87, R Romano4,5, J H Romie7, D Rosińska43,134, S Rowan36, A Rüdiger10, P Ruggi34, K Ryan37, S Sachdev1, T Sadecki37, L Sadeghian18, M Sakellariadou135, L Salconi34, M Saleem101, F Salemi10, A Samajdar136, L Sammut120, L M Sampson85, E J Sanchez1, V Sandberg37, J R Sanders35, B Sassolas65, B S Sathyaprakash74,94, P R Saulson35, O Sauter106, R L Savage37, A Sawadsky19, P Schale59, J Scheuer85, E Schmidt103, J Schmidt10, P Schmidt1,51, R Schnabel27, R M S Schofield59, A Schönbeck27, E Schreiber10, D Schuette10,19, B F Schutz29,94, S G Schwalbe103, J Scott36, S M Scott22, D Sellers7, A S Sengupta137, D Sentenac34, V Sequino15,26, A Sergeev113, Y Setyawati11,53, D A Shaddock22, T J Shaffer37, M S Shahriar85, B Shapiro40, P Shawhan64, A Sheperd18, D H Shoemaker12, D M Shoemaker44, K Siellez44, X Siemens18, M Sieniawska43, D Sigg37, A D Silva13, A Singer1, L P Singer68, A Singh10,19,29, R Singh2, A Singhal14, A M Sintes86, B J J Slagmolen22, B Smith7, J R Smith23, R J E Smith1, E J Son116, B Sorazu36, F Sorrentino47, T Souradeep16, A P Spencer36, A K Srivastava89, A Staley39, M Steinke10, J Steinlechner36, S Steinlechner27,36, D Steinmeyer10,19, B C Stephens18, S P Stevenson45, R Stone87, K A Strain36, N Straniero65, G Stratta57,58, S E Strigin49, R Sturani130, A L Stuver7, T Z Summerscales138, L Sun128, S Sunil89, P J Sutton94, B L Swinkels34, M J Szczepańczyk103, M Tacca30, D Talukder59, D B Tanner6, M Tápai102, A Taracchini29, R Taylor1, T Theeg10, E G Thomas45, M Thomas7, P Thomas37, K A Thorne7, E Thrane120, T Tippens44, S Tiwari14,93, V Tiwari94, K V Tokmakov110, K Toland36, C Tomlinson90, M Tonelli20,21, Z Tornasi36, C I Torrie1, D Töyrä45, F Travasso32,33, G Traylor7, D Trifirò73, J Trinastic6, M C Tringali92,93, L Trozzo21,139, M Tse12, R Tso1, M Turconi54, D Tuyenbayev87, D Ugolini140, C S Unnikrishnan104, A L Urban1, S A Usman94, H Vahlbruch19, G Vajente1, G Valdes87, N van Bakel11, M van Beuzekom11, J F J van den Brand11,63, C Van Den Broeck11, D C Vander-Hyde35, L van der Schaaf11, J V van Heijningen11, A A van Veggel36, M Vardaro41,42, V Varma51, S Vass1, M Vasúth38, A Vecchio45, G Vedovato42, J Veitch45, P J Veitch70, K Venkateswara141, G Venugopalan1, D Verkindt8, F Vetrano57,58, A Viceré57,58, A D Viets18, S Vinciguerra45, D J Vine50, J-Y Vinet54, S Vitale12, T Vo35, H Vocca32,33, C Vorvick37, D V Voss6, W D Vousden45, S P Vyatchanin49, A R Wade1, L E Wade78, M Wade78, M Walker2, L Wallace1, S Walsh10,29, G Wang14,58, H Wang45, M Wang45, Y Wang52, R L Ward22, J Warner37, M Was8, J Watchi82, B Weaver37, L-W Wei54, M Weinert10, A J Weinstein1, R Weiss12, L Wen52, P Weßels10, T Westphal10, K Wette10, J T Whelan107, B F Whiting6, C Whittle120, D Williams36, R D Williams1, A R Williamson94, J L Willis142, B Willke10,19, M H Wimmer10,19, W Winkler10, C C Wipf1, H Wittel10,19, G Woan36, J Woehler10, J Worden37, J L Wright36, D S Wu10, G Wu7, W Yam12, H Yamamoto1, C C Yancey64, M J Yap22, Hang Yu12, Haocun Yu12, M Yvert8, A Zadrożny118, L Zangrando42, M Zanolin103, J-P Zendri42, M Zevin85, L Zhang1, M Zhang129, T Zhang36, Y Zhang107, C Zhao52, M Zhou85, Z Zhou85, S J Zhu10,29, X J Zhu52, M E Zucker1,12, J Zweizig1 (LIGO Scientific Collaboration, Virgo Collaboration), M Boyle143, T Chu97, D Hemberger51, I Hinder29, L E Kidder143, S Ossokine29, M Scheel51, B Szilagyi51, S Teukolsky143 and A Vano Vinuales94 Hide full author list Published 12 April 2017 • © 2017 IOP Publishing Ltd Classical and Quantum Gravity, Volume 34, Number 10 Focus Issue: Gravitational Waves Article PDF Figures References Citations PDF 258 Total downloads Cited by 1 articles Article has an altmetric score of 3 Turn on MathJax Get permission to re-use this article Share this article Article information Abstract Parameter estimates of GW150914 were obtained using Bayesian inference, based on three semi-analytic waveform models for binary black hole coalescences. These waveform models differ from each other in their treatment of black hole spins, and all three models make some simplifying assumptions, notably to neglect sub-dominant waveform harmonic modes and orbital eccentricity. Furthermore, while the models are calibrated to agree with waveforms obtained by full numerical solutions of Einstein's equations, any such calibration is accurate only to some non-zero tolerance and is limited by the accuracy of the underlying phenomenology, availability, quality, and parameter-space coverage of numerical simulations. This paper complements the original analyses of GW150914 with an investigation of the effects of possible systematic errors in the waveform models on estimates of its source parameters. To test for systematic errors we repeat the original Bayesian analysis on mock signals from numerical simulations of a series of binary configurations with parameters similar to those found for GW150914. Overall, we find no evidence for a systematic bias relative to the statistical error of the original parameter recovery of GW150914 due to modeling approximations or modeling inaccuracies. However, parameter biases are found to occur for some configurations disfavored by the data of GW150914: for binaries inclined edge-on to the detector over a small range of choices of polarization angles, and also for eccentricities greater than ~0.05. For signals with higher signal-to-noise ratio than GW150914, or in other regions of the binary parameter space (lower masses, larger mass ratios, or higher spins), we expect that systematic errors in current waveform models may impact gravitational-wave measurements, making more accurate models desirable for future observations

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

An improved analysis of GW150914 using a fully spin-precessing waveform model

This paper presents updated estimates of source parameters for GW150914, a binary black-hole coalescence event detected by the Laser Interferometer Gravitational-wave Observatory (LIGO) on September 14, 2015 [1]. Reference presented parameter estimation [2] of the source using a 13-dimensional, phenomenological precessing-spin model (precessing IMRPhenom) and a 11-dimensional nonprecessing effective-one-body (EOB) model calibrated to numerical-relativity simulations, which forces spin alignment (nonprecessing EOBNR). Here we present new results that include a 15-dimensional precessing-spin waveform model (precessing EOBNR) developed within the EOB formalism. We find good agreement with the parameters estimated previously [2], and we quote updated component masses of $35^{+5}_{-3}\mathrm{M}_\odot$ and $30^{+3}_{-4}\mathrm{M}_\odot$ (where errors correspond to 90% symmetric credible intervals). We also present slightly tighter constraints on the dimensionless spin magnitudes of the two black holes, with a primary spin estimate $0.65$ and a secondary spin estimate $0.75$ at 90% probability. Reference [2] estimated the systematic parameter-extraction errors due to waveform-model uncertainty by combining the posterior probability densities of precessing IMRPhenom and nonprecessing EOBNR. Here we find that the two precessing-spin models are in closer agreement, suggesting that these systematic errors are smaller than previously quoted

Properties of the Binary Black Hole Merger GW150914

On September 14, 2015, the Laser Interferometer Gravitational-Wave Observatory (LIGO) detected a gravitational-wave transient (GW150914); we characterize the properties of the source and its parameters. The data around the time of the event were analyzed coherently across the LIGO network using a suite of accurate waveform models that describe gravitational waves from a compact binary system in general relativity. GW150914 was produced by a nearly equal mass binary black hole of masses 36+5−4M⊙ and 29+4−4M⊙; for each parameter we report the median value and the range of the 90% credible interval. The dimensionless spin magnitude of the more massive black hole is bound to be <0.7 (at 90% probability). The luminosity distance to the source is 410+160−180  Mpc, corresponding to a redshift 0.09+0.03−0.04 assuming standard cosmology. The source location is constrained to an annulus section of 610  deg2, primarily in the southern hemisphere. The binary merges into a black hole of mass 62+4−4M⊙ and spin 0.67+0.05−0.07. This black hole is significantly more massive than any other inferred from electromagnetic observations in the stellar-mass regime