ALBERT

Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Rogers Hollingsworth, J -- Muller, Karl H -- Hollingsworth, Ellen Jane -- England -- Nature. 2008 Jul 24;454(7203):412-3. doi: 10.1038/454412a.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉University of Wisconsin (Madison), 455 North Park Street, Madison, Wisconsin 53706, USA. hollingsjr@aol.com〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18650902" target="_blank"〉PubMed〈/a〉

Description: A stochastic background of gravitational waves is expected to arise from a superposition of a large number of unresolved gravitational-wave sources of astrophysical and cosmological origin. It should carry unique signatures from the earliest epochs in the evolution of the Universe, inaccessible to standard astrophysical observations. Direct measurements of the amplitude of this background are therefore of fundamental importance for understanding the evolution of the Universe when it was younger than one minute. Here we report limits on the amplitude of the stochastic gravitational-wave background using the data from a two-year science run of the Laser Interferometer Gravitational-wave Observatory (LIGO). Our result constrains the energy density of the stochastic gravitational-wave background normalized by the critical energy density of the Universe, in the frequency band around 100 Hz, to be 〈6.9 x 10(-6) at 95% confidence. The data rule out models of early Universe evolution with relatively large equation-of-state parameter, as well as cosmic (super)string models with relatively small string tension that are favoured in some string theory models. This search for the stochastic background improves on the indirect limits from Big Bang nucleosynthesis and cosmic microwave background at 100 Hz.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉LIGO Scientific Collaboration & Virgo Collaboration -- Abbott, B P -- Abbott, R -- Acernese, F -- Adhikari, R -- Ajith, P -- Allen, B -- Allen, G -- Alshourbagy, M -- Amin, R S -- Anderson, S B -- Anderson, W G -- Antonucci, F -- Aoudia, S -- Arain, M A -- Araya, M -- Armandula, H -- Armor, P -- Arun, K G -- Aso, Y -- Aston, S -- Astone, P -- Aufmuth, P -- Aulbert, C -- Babak, S -- Baker, P -- Ballardin, G -- Ballmer, S -- Barker, C -- Barker, D -- Barone, F -- Barr, B -- Barriga, P -- Barsotti, L -- Barsuglia, M -- Barton, M A -- Bartos, I -- Bassiri, R -- Bastarrika, M -- Bauer, Th S -- Behnke, B -- Beker, M -- Benacquista, M -- Betzwieser, J -- Beyersdorf, P T -- Bigotta, S -- Bilenko, I A -- Billingsley, G -- Birindelli, S -- Biswas, R -- Bizouard, M A -- Black, E -- Blackburn, J K -- Blackburn, L -- Blair, D -- Bland, B -- Boccara, C -- Bodiya, T P -- Bogue, L -- Bondu, F -- Bonelli, L -- Bork, R -- Boschi, V -- Bose, S -- Bosi, L -- Braccini, S -- Bradaschia, C -- Brady, P R -- Braginsky, V B -- Brand, J F J van den -- Brau, J E -- Bridges, D O -- Brillet, A -- Brinkmann, M -- Brisson, V -- Van Den Broeck, C -- Brooks, A F -- Brown, D A -- Brummit, A -- Brunet, G -- Bullington, A -- Bulten, H J -- Buonanno, A -- Burmeister, O -- Buskulic, D -- Byer, R L -- Cadonati, L -- Cagnoli, G -- Calloni, E -- Camp, J B -- Campagna, E -- Cannizzo, J -- Cannon, K C -- Canuel, B -- Cao, J -- Carbognani, F -- Cardenas, L -- Caride, S -- Castaldi, G -- Caudill, S -- Cavaglia, M -- Cavalier, F -- Cavalieri, R -- Cella, G -- Cepeda, C -- Cesarini, E -- Chalermsongsak, T -- Chalkley, E -- Charlton, P -- Chassande-Mottin, E -- Chatterji, S -- Chelkowski, S -- Chen, Y -- Christensen, N -- Chung, C T Y -- Clark, D -- Clark, J -- Clayton, J H -- Cleva, F -- Coccia, E -- Cokelaer, T -- Colacino, C N -- Colas, J -- Colla, A -- Colombini, M -- Conte, R -- Cook, D -- Corbitt, T R C -- Corda, C -- Cornish, N -- Corsi, A -- Coulon, J-P -- Coward, D -- Coyne, D C -- Creighton, J D E -- Creighton, T D -- Cruise, A M -- Culter, R M -- Cumming, A -- Cunningham, L -- Cuoco, E -- Danilishin, S L -- D'Antonio, S -- Danzmann, K -- Dari, A -- Dattilo, V -- Daudert, B -- Davier, M -- Davies, G -- Daw, E J -- Day, R -- De Rosa, R -- Debra, D -- Degallaix, J -- Del Prete, M -- Dergachev, V -- Desai, S -- Desalvo, R -- Dhurandhar, S -- Di Fiore, L -- Di Lieto, A -- Di Paolo Emilio, M -- Di Virgilio, A -- Diaz, M -- Dietz, A -- Donovan, F -- Dooley, K L -- Doomes, E E -- Drago, M -- Drever, R W P -- Dueck, J -- Duke, I -- Dumas, J-C -- Dwyer, J G -- Echols, C -- Edgar, M -- Effler, A -- Ehrens, P -- Ely, G -- Espinoza, E -- Etzel, T -- Evans, M -- Evans, T -- Fafone, V -- Fairhurst, S -- Faltas, Y -- Fan, Y -- Fazi, D -- Fehrmann, H -- Ferrante, I -- Fidecaro, F -- Finn, L S -- Fiori, I -- Flaminio, R -- Flasch, K -- Foley, S -- Forrest, C -- Fotopoulos, N -- Fournier, J-D -- Franc, J -- Franzen, A -- Frasca, S -- Frasconi, F -- Frede, M -- Frei, M -- Frei, Z -- Freise, A -- Frey, R -- Fricke, T -- Fritschel, P -- Frolov, V V -- Fyffe, M -- Galdi, V -- Gammaitoni, L -- Garofoli, J A -- Garufi, F -- Genin, E -- Gennai, A -- Gholami, I -- Giaime, J A -- Giampanis, S -- Giardina, K D -- Giazotto, A -- Goda, K -- Goetz, E -- Goggin, L M -- Gonzalez, G -- Gorodetsky, M L -- Gobler, S -- Gouaty, R -- Granata, M -- Granata, V -- Grant, A -- Gras, S -- Gray, C -- Gray, M -- Greenhalgh, R J S -- Gretarsson, A M -- Greverie, C -- Grimaldi, F -- Grosso, R -- Grote, H -- Grunewald, S -- Guenther, M -- Guidi, G -- Gustafson, E K -- Gustafson, R -- Hage, B -- Hallam, J M -- Hammer, D -- Hammond, G D -- Hanna, C -- Hanson, J -- Harms, J -- Harry, G M -- Harry, I W -- Harstad, E D -- Haughian, K -- Hayama, K -- Heefner, J -- Heitmann, H -- Hello, P -- Heng, I S -- Heptonstall, A -- Hewitson, M -- Hild, S -- Hirose, E -- Hoak, D -- Hodge, K A -- Holt, K -- Hosken, D J -- Hough, J -- Hoyland, D -- Huet, D -- Hughey, B -- Huttner, S H -- Ingram, D R -- Isogai, T -- Ito, M -- Ivanov, A -- Johnson, B -- Johnson, W W -- Jones, D I -- Jones, G -- Jones, R -- Sancho de la Jordana, L -- Ju, L -- Kalmus, P -- Kalogera, V -- Kandhasamy, S -- Kanner, J -- Kasprzyk, D -- Katsavounidis, E -- Kawabe, K -- Kawamura, S -- Kawazoe, F -- Kells, W -- Keppel, D G -- Khalaidovski, A -- Khalili, F Y -- Khan, R -- Khazanov, E -- King, P -- Kissel, J S -- Klimenko, S -- Kokeyama, K -- Kondrashov, V -- Kopparapu, R -- Koranda, S -- Kozak, D -- Krishnan, B -- Kumar, R -- Kwee, P -- La Penna, P -- Lam, P K -- Landry, M -- Lantz, B -- Laval, M -- Lazzarini, A -- Lei, H -- Lei, M -- Leindecker, N -- Leonor, I -- Leroy, N -- Letendre, N -- Li, C -- Lin, H -- Lindquist, P E -- Littenberg, T B -- Lockerbie, N A -- Lodhia, D -- Longo, M -- Lorenzini, M -- Loriette, V -- Lormand, M -- Losurdo, G -- Lu, P -- Lubinski, M -- Lucianetti, A -- Luck, H -- Machenschalk, B -- Macinnis, M -- Mackowski, J-M -- Mageswaran, M -- Mailand, K -- Majorana, E -- Man, N -- Mandel, I -- Mandic, V -- Mantovani, M -- Marchesoni, F -- Marion, F -- Marka, S -- Marka, Z -- Markosyan, A -- Markowitz, J -- Maros, E -- Marque, J -- Martelli, F -- Martin, I W -- Martin, R M -- Marx, J N -- Mason, K -- Masserot, A -- Matichard, F -- Matone, L -- Matzner, R A -- Mavalvala, N -- McCarthy, R -- McClelland, D E -- McGuire, S C -- McHugh, M -- McIntyre, G -- McKechan, D J A -- McKenzie, K -- Mehmet, M -- Melatos, A -- Melissinos, A C -- Mendell, G -- Menendez, D F -- Menzinger, F -- Mercer, R A -- Meshkov, S -- Messenger, C -- Meyer, M S -- Michel, C -- Milano, L -- Miller, J -- Minelli, J -- Minenkov, Y -- Mino, Y -- Mitrofanov, V P -- Mitselmakher, G -- Mittleman, R -- Miyakawa, O -- Moe, B -- Mohan, M -- Mohanty, S D -- Mohapatra, S R P -- Moreau, J -- Moreno, G -- Morgado, N -- Morgia, A -- Morioka, T -- Mors, K -- Mosca, S -- Mossavi, K -- Mours, B -- Mowlowry, C -- Mueller, G -- Muhammad, D -- Muhlen, H Zur -- Mukherjee, S -- Mukhopadhyay, H -- Mullavey, A -- Muller-Ebhardt, H -- Munch, J -- Murray, P G -- Myers, E -- Myers, J -- Nash, T -- Nelson, J -- Neri, I -- Newton, G -- Nishizawa, A -- Nocera, F -- Numata, K -- Ochsner, E -- O'Dell, J -- Ogin, G H -- O'Reilly, B -- O'Shaughnessy, R -- Ottaway, D J -- Ottens, R S -- Overmier, H -- Owen, B J -- Pagliaroli, G -- Palomba, C -- Pan, Y -- Pankow, C -- Paoletti, F -- Papa, M A -- Parameshwaraiah, V -- Pardi, S -- Pasqualetti, A -- Passaquieti, R -- Passuello, D -- Patel, P -- Pedraza, M -- Penn, S -- Perreca, A -- Persichetti, G -- Pichot, M -- Piergiovanni, F -- Pierro, V -- Pinard, L -- Pinto, I M -- Pitkin, M -- Pletsch, H J -- Plissi, M V -- Poggiani, R -- Postiglione, F -- Principe, M -- Prix, R -- Prodi, G A -- Prokhorov, L -- Punken, O -- Punturo, M -- Puppo, P -- Putten, S van der -- Quetschke, V -- Raab, F J -- Rabaste, O -- Rabeling, D S -- Radkins, H -- Raffai, P -- Raics, Z -- Rainer, N -- Rakhmanov, M -- Rapagnani, P -- Raymond, V -- Re, V -- Reed, C M -- Reed, T -- Regimbau, T -- Rehbein, H -- Reid, S -- Reitze, D H -- Ricci, F -- Riesen, R -- Riles, K -- Rivera, B -- Roberts, P -- Robertson, N A -- Robinet, F -- Robinson, C -- Robinson, E L -- Rocchi, A -- Roddy, S -- Rolland, L -- Rollins, J -- Romano, J D -- Romano, R -- Romie, J H -- Rover, C -- Rowan, S -- Rudiger, A -- Ruggi, P -- Russell, P -- Ryan, K -- Sakata, S -- Salemi, F -- Sandberg, V -- Sannibale, V -- Santamaria, L -- Saraf, S -- Sarin, P -- Sassolas, B -- Sathyaprakash, B S -- Sato, S -- Satterthwaite, M -- Saulson, P R -- Savage, R -- Savov, P -- Scanlan, M -- Schilling, R -- Schnabel, R -- Schofield, R -- Schulz, B -- Schutz, B F -- Schwinberg, P -- Scott, J -- Scott, S M -- Searle, A C -- Sears, B -- Seifert, F -- Sellers, D -- Sengupta, A S -- Sentenac, D -- Sergeev, A -- Shapiro, B -- Shawhan, P -- Shoemaker, D H -- Sibley, A -- Siemens, X -- Sigg, D -- Sinha, S -- Sintes, A M -- Slagmolen, B J J -- Slutsky, J -- van der Sluys, M V -- Smith, J R -- Smith, M R -- Smith, N D -- Somiya, K -- Sorazu, B -- Stein, A -- Stein, L C -- Steplewski, S -- Stochino, A -- Stone, R -- Strain, K A -- Strigin, S -- Stroeer, A -- Sturani, R -- Stuver, A L -- Summerscales, T Z -- Sun, K-X -- Sung, M -- Sutton, P J -- Swinkels, B L -- Szokoly, G P -- Talukder, D -- Tang, L -- Tanner, D B -- Tarabrin, S P -- Taylor, J R -- Taylor, R -- Terenzi, R -- Thacker, J -- Thorne, K A -- Thorne, K S -- Thuring, A -- Tokmakov, K V -- Toncelli, A -- Tonelli, M -- Torres, C -- Torrie, C -- Tournefier, E -- Travasso, F -- Traylor, G -- Trias, M -- Trummer, J -- Ugolini, D -- Ulmen, J -- Urbanek, K -- Vahlbruch, H -- Vajente, G -- Vallisneri, M -- Vass, S -- Vaulin, R -- Vavoulidis, M -- Vecchio, A -- Vedovato, G -- van Veggel, A A -- Veitch, J -- Veitch, P -- Veltkamp, C -- Verkindt, D -- Vetrano, F -- Vicere, A -- Villar, A -- Vinet, J-Y -- Vocca, H -- Vorvick, C -- Vyachanin, S P -- Waldman, S J -- Wallace, L -- Ward, H -- Ward, R L -- Was, M -- Weidner, A -- Weinert, M -- Weinstein, A J -- Weiss, R -- Wen, L -- Wen, S -- Wette, K -- Whelan, J T -- Whitcomb, S E -- Whiting, B F -- Wilkinson, C -- Willems, P A -- Williams, H R -- Williams, L -- Willke, B -- Wilmut, I -- Winkelmann, L -- Winkler, W -- Wipf, C C -- Wiseman, A G -- Woan, G -- Wooley, R -- Worden, J -- Wu, W -- Yakushin, I -- Yamamoto, H -- Yan, Z -- Yoshida, S -- Yvert, M -- Zanolin, M -- Zhang, J -- Zhang, L -- Zhao, C -- Zotov, N -- Zucker, M E -- Zweizig, J -- England -- Nature. 2009 Aug 20;460(7258):990-4. doi: 10.1038/nature08278.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Lists of participants and their affiliations appear at the end of the paper.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19693079" target="_blank"〉PubMed〈/a〉

Description: The concept of hierarchical bottom-up structuring commonly encountered in natural materials provides inspiration for the design of complex artificial materials with advanced functionalities. Natural processes have achieved the orchestration of multicomponent systems across many length scales with very high precision, but man-made self-assemblies still face obstacles in realizing well-defined hierarchical structures. In particle-based self-assembly, the challenge is to program symmetries and periodicities of superstructures by providing monodisperse building blocks with suitable shape anisotropy or anisotropic interaction patterns ('patches'). Irregularities in particle architecture are intolerable because they generate defects that amplify throughout the hierarchical levels. For patchy microscopic hard colloids, this challenge has been approached by using top-down methods (such as metal shading or microcontact printing), enabling molecule-like directionality during aggregation. However, both top-down procedures and particulate systems based on molecular assembly struggle to fabricate patchy particles controllably in the desired size regime (10-100 nm). Here we introduce the co-assembly of dynamic patchy nanoparticles--that is, soft patchy nanoparticles that are intrinsically self-assembled and monodisperse--as a modular approach for producing well-ordered binary and ternary supracolloidal hierarchical assemblies. We bridge up to three hierarchical levels by guiding triblock terpolymers (length scale approximately 10 nm) to form soft patchy nanoparticles (20-50 nm) of different symmetries that, in combination, co-assemble into substructured, compartmentalized materials (〉10 mum) with predictable and tunable nanoscale periodicities. We establish how molecular control over polymer composition programs the building block symmetries and regulates particle positioning, offering a route to well-ordered mixed mesostructures of high complexity.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Groschel, Andre H -- Walther, Andreas -- Lobling, Tina I -- Schacher, Felix H -- Schmalz, Holger -- Muller, Axel H E -- England -- Nature. 2013 Nov 14;503(7475):247-51. doi: 10.1038/nature12610. Epub 2013 Nov 3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Makromolekulare Chemie II, Universitat Bayreuth, D-95440 Bayreuth, Germany [2] Department of Applied Physics, Aalto University, FI-02150 Espoo, Finland (A.H.G.); Institute of Organic Chemistry, Johannes Gutenberg-Universitat, D-55099 Mainz, Germany (A.H.E.M.).〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24185010" target="_blank"〉PubMed〈/a〉

Description: Recent advances in DNA synthesis technology have enabled the construction of novel genetic pathways and genomic elements, furthering our understanding of system-level phenomena. The ability to synthesize large segments of DNA allows the engineering of pathways and genomes according to arbitrary sets of design principles. Here we describe a synthetic yeast genome project, Sc2.0, and the first partially synthetic eukaryotic chromosomes, Saccharomyces cerevisiae chromosome synIXR, and semi-synVIL. We defined three design principles for a synthetic genome as follows: first, it should result in a (near) wild-type phenotype and fitness; second, it should lack destabilizing elements such as tRNA genes or transposons; and third, it should have genetic flexibility to facilitate future studies. The synthetic genome features several systemic modifications complying with the design principles, including an inducible evolution system, SCRaMbLE (synthetic chromosome rearrangement and modification by loxP-mediated evolution). We show the utility of SCRaMbLE as a novel method of combinatorial mutagenesis, capable of generating complex genotypes and a broad variety of phenotypes. When complete, the fully synthetic genome will allow massive restructuring of the yeast genome, and may open the door to a new type of combinatorial genetics based entirely on variations in gene content and copy number.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3774833/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3774833/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Dymond, Jessica S -- Richardson, Sarah M -- Coombes, Candice E -- Babatz, Timothy -- Muller, Heloise -- Annaluru, Narayana -- Blake, William J -- Schwerzmann, Joy W -- Dai, Junbiao -- Lindstrom, Derek L -- Boeke, Annabel C -- Gottschling, Daniel E -- Chandrasegaran, Srinivasan -- Bader, Joel S -- Boeke, Jef D -- AG023779/AG/NIA NIH HHS/ -- R01 AG023779/AG/NIA NIH HHS/ -- R37 AG023779/AG/NIA NIH HHS/ -- England -- Nature. 2011 Sep 14;477(7365):471-6. doi: 10.1038/nature10403.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉High Throughput Biology Center, Johns Hopkins University School of Medicine, 733 North Broadway, Baltimore, Maryland 21205, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21918511" target="_blank"〉PubMed〈/a〉

Description: The c-myc proto-oncogene product, Myc, is a transcription factor that binds thousands of genomic loci. Recent work suggested that rather than up- and downregulating selected groups of genes, Myc targets all active promoters and enhancers in the genome (a phenomenon termed 'invasion') and acts as a general amplifier of transcription. However, the available data did not readily discriminate between direct and indirect effects of Myc on RNA biogenesis. We addressed this issue with genome-wide chromatin immunoprecipitation and RNA expression profiles during B-cell lymphomagenesis in mice, in cultured B cells and fibroblasts. Consistent with long-standing observations, we detected general increases in total RNA or messenger RNA copies per cell (hereby termed 'amplification') when comparing actively proliferating cells with control quiescent cells: this was true whether cells were stimulated by mitogens (requiring endogenous Myc for a proliferative response) or by deregulated, oncogenic Myc activity. RNA amplification and promoter/enhancer invasion by Myc were separable phenomena that could occur without one another. Moreover, whether or not associated with RNA amplification, Myc drove the differential expression of distinct subsets of target genes. Hence, although having the potential to interact with all active or poised regulatory elements in the genome, Myc does not directly act as a global transcriptional amplifier. Instead, our results indicate that Myc activates and represses transcription of discrete gene sets, leading to changes in cellular state that can in turn feed back on global RNA production and turnover.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4110711/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4110711/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Sabo, Arianna -- Kress, Theresia R -- Pelizzola, Mattia -- de Pretis, Stefano -- Gorski, Marcin M -- Tesi, Alessandra -- Morelli, Marco J -- Bora, Pranami -- Doni, Mirko -- Verrecchia, Alessandro -- Tonelli, Claudia -- Faga, Giovanni -- Bianchi, Valerio -- Ronchi, Alberto -- Low, Diana -- Muller, Heiko -- Guccione, Ernesto -- Campaner, Stefano -- Amati, Bruno -- 10-0245/Worldwide Cancer Research/United Kingdom -- 268671/European Research Council/International -- England -- Nature. 2014 Jul 24;511(7510):488-92. doi: 10.1038/nature13537. Epub 2014 Jul 9.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉1] Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia (IIT), Via Adamello 16, 20139 Milan, Italy [2] Department of Experimental Oncology, European Institute of Oncology (IEO), Via Adamello 16, 20139 Milan, Italy [3]. ; 1] Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia (IIT), Via Adamello 16, 20139 Milan, Italy [2]. ; Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia (IIT), Via Adamello 16, 20139 Milan, Italy. ; Department of Experimental Oncology, European Institute of Oncology (IEO), Via Adamello 16, 20139 Milan, Italy. ; Institute of Molecular and Cell Biology, Singapore 138673, Singapore. ; 1] Center for Genomic Science of IIT@SEMM, Fondazione Istituto Italiano di Tecnologia (IIT), Via Adamello 16, 20139 Milan, Italy [2] Department of Experimental Oncology, European Institute of Oncology (IEO), Via Adamello 16, 20139 Milan, Italy.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25043028" target="_blank"〉PubMed〈/a〉

Description: One of the central predictions of metric theories of gravity, such as general relativity, is that a clock in a gravitational potential U will run more slowly by a factor of 1 + U/c(2), where c is the velocity of light, as compared to a similar clock outside the potential. This effect, known as gravitational redshift, is important to the operation of the global positioning system, timekeeping and future experiments with ultra-precise, space-based clocks (such as searches for variations in fundamental constants). The gravitational redshift has been measured using clocks on a tower, an aircraft and a rocket, currently reaching an accuracy of 7 x 10(-5). Here we show that laboratory experiments based on quantum interference of atoms enable a much more precise measurement, yielding an accuracy of 7 x 10(-9). Our result supports the view that gravity is a manifestation of space-time curvature, an underlying principle of general relativity that has come under scrutiny in connection with the search for a theory of quantum gravity. Improving the redshift measurement is particularly important because this test has been the least accurate among the experiments that are required to support curved space-time theories.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Muller, Holger -- Peters, Achim -- Chu, Steven -- England -- Nature. 2010 Feb 18;463(7283):926-9. doi: 10.1038/nature08776.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physics, 366 Le Conte Hall MS 7300, University of California, Berkeley, California 94720, USA. hm@berkeley.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20164925" target="_blank"〉PubMed〈/a〉