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You searched for: Journal Science Remove constraint Journal: Science Publication Year 2006 Remove constraint Publication Year: 2006 Source 2006 v.314 no.5799 Remove constraint Source: 2006 v.314 no.5799
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1. A Centrosome-Independent Role for γ-TuRC Proteins in the Spindle Assembly Checkpoint

Author:
Müller, Hannah; Fogeron, Marie-Laure; Lehmann, Verena; Lehrach, Hans; Lange, Bodo M.H.
Source:
Science 2006 v.314 no.5799 pp. 654-657
ISSN:
0036-8075
Subject:
centrosomes; chromosome segregation; microtubules; regulatory proteins; tubulin
Abstract:
... The spindle assembly checkpoint guards the fidelity of chromosome segregation. It requires the close cooperation of cell cycle regulatory proteins and cytoskeletal elements to sense spindle integrity. The role of the centrosome, the organizing center of the microtubule cytoskeleton, in the spindle checkpoint is unclear. We found that the molecular requirements for a functional spindle checkpoint i ...
DOI:
10.1126/science.1132834

2. A Fossil Bee from Early Cretaceous Burmese Amber

Author:
Poinar, G.O. Jr.; Danforth, B.N.
Source:
Science 2006 v.314 no.5799 pp. 614
ISSN:
0036-8075
Subject:
amber; bees; fossils; new family; new species; pollination
Abstract:
... The bee fossil record is fragmentary, making it difficult to accurately estimate the antiquity of bee-mediated pollination. Here, we describe a bee fossil [Melittosphex burmensis (new species), Melittosphecidae (new family)] from Early Cretaceous Burmese amber (approximately 100 million years before the present). The fossil provides insights into the morphology of the earliest bees and provides a ...
DOI:
10.1126/science.1134103

3. Anatomy of a Flaring Proto-Planetary Disk Around a Young Intermediate-Mass Star

Author:
Lagage, Pierre-Olivier; Doucet, Coralie; Pantin, Eric; Habart, Emilie; Duchêne, Gaspard; Ménard, François; Pinte, Christophe; Charnoz, Sébastien; Pel, Jan-Willem
Source:
Science 2006 v.314 no.5799 pp. 621-623
ISSN:
0036-8075
Subject:
dust; geometry; polycyclic aromatic hydrocarbons
Abstract:
... Although planets are being discovered around stars more massive than the Sun, information about the proto-planetary disks where such planets have built up is sparse. We have imaged mid-infrared emission from polycyclic aromatic hydrocarbons at the surface of the disk surrounding the young intermediate-mass star HD 97048 and characterized the disk. The disk is in an early stage of evolution, as ind ...
DOI:
10.1126/science.1131436

4. Bacterial Taxa That Limit Sulfur Flux from the Ocean

Author:
Howard, Erinn C.; Henriksen, James R.; Buchan, Alison; Reisch, Chris R.; Bürgmann, Helmut; Welsh, Rory; Ye, Wenying; González, José M.; Mace, Kimberly; Joye, Samantha B.; Kiene, Ronald P.; Whitman, William B.; Moran, Mary Ann
Source:
Science 2006 v.314 no.5799 pp. 649-652
ISSN:
0036-8075
Subject:
Roseobacter; aerosols; bacteria; bacterioplankton; climate; dimethyl sulfide; dimethylsulfoniopropionate; food webs; methyltransferases; primary productivity; sulfur; surface water
Abstract:
... Flux of dimethylsulfide (DMS) from ocean surface waters is the predominant natural source of sulfur to the atmosphere and influences climate by aerosol formation. Marine bacterioplankton regulate sulfur flux by converting the precursor dimethylsulfoniopropionate (DMSP) either to DMS or to sulfur compounds that are not climatically active. Through the discovery of a glycine cleavage T-family protei ...
DOI:
10.1126/science.1130657

5. BKCa-Cav Channel Complexes Mediate Rapid and Localized Ca²⁺-Activated K⁺ Signaling

Author:
Berkefeld, Henrike; Sailer, Claudia A.; Bildl, Wolfgang; Rohde, Volker; Thumfart, Jörg-Oliver; Eble, Silke; Klugbauer, Norbert; Reisinger, Ellen; Bischofberger, Josef; Oliver, Dominik; Knaus, Hans-Günther; Schulte, Uwe; Fakler, Bernd
Source:
Science 2006 v.314 no.5799 pp. 615-620
ISSN:
0036-8075
Subject:
brain; calcium; calcium channels; hormones; ions; neurons; potassium; potassium channels; rats
Abstract:
... Large-conductance calcium- and voltage-activated potassium channels (BKCa) are dually activated by membrane depolarization and elevation of cytosolic calcium ions (Ca²⁺). Under normal cellular conditions, BKCa channel activation requires Ca²⁺ concentrations that typically occur in close proximity to Ca²⁺ sources. We show that BKCa channels affinity-purified from rat brain are assembled into macrom ...
DOI:
10.1126/science.1132915

6. Brownian Motion of an Ellipsoid

Author:
Han, Y.; Alsayed, A.M.; Nobili, M.; Zhang, J.; Lubensky, T.C.; Yodh, A.G.
Source:
Science 2006 v.314 no.5799 pp. 626-630
ISSN:
0036-8075
Subject:
mathematical models; microscopy; probability distribution
Abstract:
... We studied the Brownian motion of isolated ellipsoidal particles in water confined to two dimensions and elucidated the effects of coupling between rotational and translational motion. By using digital video microscopy, we quantified the crossover from short-time anisotropic to long-time isotropic diffusion and directly measured probability distributions functions for displacements. We confirmed a ...
DOI:
10.1126/science.1130146

7. Colloid Transport of Plutonium in the Far-Field of the Mayak Production Association, Russia

Author:
Novikov, Alexander P.; Kalmykov, Stepan N.; Utsunomiya, Satoshi; Ewing, Rodney C.; Horreard, François; Merkulov, Alex; Clark, Sue B.; Tkachev, Vladimir V.; Myasoedov, Boris F.
Source:
Science 2006 v.314 no.5799 pp. 638-641
ISSN:
0036-8075
Subject:
carbonates; colloids; groundwater; hydroxides; iron oxides; mass spectrometry; plutonium; sorption; uranium; Russia
Abstract:
... Sorption of actinides, particularly plutonium, onto submicrometer-sized colloids increases their mobility, but these plutonium colloids are difficult to detect in the far-field. We identified actinides on colloids in the groundwater from the Mayak Production Association, Urals, Russia; at the source, the plutonium activity is ~1000 becquerels per liter. Plutonium activities are still 0.16 becquere ...
DOI:
10.1126/science.1131307

8. Comment on "Preindustrial to Modern Interdecadal Variability in Coral Reef pH"

Author:
Matear, Richard J.; McNeil, Ben I.
Source:
Science 2006 v.314 no.5799 pp. 595b
ISSN:
0036-8075
Subject:
boron; carbon; coral reefs; corals; ecosystems; ocean acidification; pH
Abstract:
... Based on the boron isotopic composition of coral from the southwestern Pacific, Pelejero et al. (Reports, 30 September 2005, p. 2204) suggested that natural variations in pH can modulate the impact of ocean acidification on coral reef ecosystems. We show that this claim cannot be reconciled with other marine carbon chemistry constraints and highlight problems with the authors' interpretation of th ...
DOI:
10.1126/science.1128198

9. Control of Peripheral Nerve Myelination by the β-Secretase BACE1

Author:
Willem, Michael; Garratt, Alistair N.; Novak, Bozidar; Citron, Martin; Kaufmann, Steve; Rittger, Andrea; DeStrooper, Bart; Saftig, Paul; Birchmeier, Carmen; Haass, Christian
Source:
Science 2006 v.314 no.5799 pp. 664-666
ISSN:
0036-8075
Subject:
Alzheimer disease; Schwann cells; amyloid; axons; mice; mutation; myelination; nerve tissue; peripheral nerves
Abstract:
... Although BACE1 (beta-site amyloid precursor protein-cleaving enzyme 1) is essential for the generation of amyloid-b peptide in Alzheimer's disease, its physiological function is unclear. We found that very high levels of BACE1 were expressed at time points when peripheral nerves become myelinated. Deficiency of BACE1 resulted in the accumulation of unprocessed neuregulin 1 (NRG1), an axonally expr ...
DOI:
10.1126/science.1132341

10. Dimethylsulfoniopropionate Uptake by Marine Phytoplankton

Author:
Vila-Costa, Maria; Simó, Rafel; Harada, Hyakubun; Gasol, Josep M.; Slezak, Doris; Kiene, Ronald P.
Source:
Science 2006 v.314 no.5799 pp. 652-654
ISSN:
0036-8075
Subject:
Bacillariophyceae; Prochlorococcus; Synechococcus; aquatic food webs; bacteria; dimethylsulfoniopropionate; phytoplankton; radiolabeling; sulfur
Abstract:
... Dimethylsulfoniopropionate (DMSP) accounts for most of the organic sulfur fluxes from primary to secondary producers in marine microbial food webs. Incubations of natural communities and axenic cultures with radio-labeled DMSP showed that dominant phytoplankton groups of the ocean, the unicellular cyanobacteria Prochlorococcus and Synechococcus and diatoms, as well as heterotrophic bacteria take u ...
DOI:
10.1126/science.1131043

11. From the Genome to the Proteome: Uncovering Peptides in the Apis Brain

Author:
Hummon, Amanda B.; Richmond, Timothy A.; Verleyen, Peter; Baggerman, Geert; Huybrechts, Jurgen; Ewing, Michael A.; Vierstraete, Evy; Rodriguez-Zas, Sandra L.; Schoofs, Liliane; Robinson, Gene E.; Sweedler, Jonathan V.
Source:
Science 2006 v.314 no.5799 pp. 647-649
ISSN:
0036-8075
Subject:
Apis mellifera; animal behavior; bioinformatics; brain; genes; neurons; neuropeptides; nucleotide sequences; proteome; proteomics
Abstract:
... Neuropeptides, critical brain peptides that modulate animal behavior by affecting the activity of almost every neuronal circuit, are inherently difficult to predict directly from a nascent genome sequence because of extensive posttranslational processing. The combination of bioinformatics and proteomics allows unprecedented neuropeptide discovery from an unannotated genome. Within the Apis mellife ...
DOI:
10.1126/science.1124128

12. Functional CpG Methylation System in a Social Insect

Author:
Wang, Ying; Jorda, Mireia; Jones, Peter L.; Maleszka, Ryszard; Ling, Xu; Robertson, Hugh M.; Mizzen, Craig A.; Peinado, Miguel A.; Robinson, Gene E.
Source:
Science 2006 v.314 no.5799 pp. 645-647
ISSN:
0036-8075
Subject:
DNA; DNA methylation; Drosophila melanogaster; bioinformatics; genes; honey bees; invertebrates; methyltransferases; social insects; vertebrates
Abstract:
... DNA methylation systems are well characterized in vertebrates, but methylation in Drosophila melanogaster and other invertebrates remains controversial. Using the recently sequenced honey bee genome, we present a bioinformatic, molecular, and biochemical characterization of a functional DNA methylation system in an insect. We report on catalytically active orthologs of the vertebrate DNA methyltra ...
DOI:
10.1126/science.1135213

13. α-Hydroxy and α-Amino Acids Under Possible Hadean, Volcanic Origin-of-Life Conditions

Author:
Huber, Claudia; Wächtershäuser, Günter
Source:
Science 2006 v.314 no.5799 pp. 630-632
ISSN:
0036-8075
Subject:
amino acids; calcium; carbon; carbon dioxide fixation; geochemistry; ligands; magnesium hydroxide; nickel; pH; volcanoes
Abstract:
... To test the theory of a chemoautotrophic origin of life in a volcanic, hydrothermal setting, we explored mechanisms for the buildup of bio-organic compounds by carbon fixation on catalytic transition metal precipitates. We report the carbon monoxide-dependent formation of carbon-fixation products, including an ordered series of α-hydroxy and α-amino acids of the general formula R-CHA-COOH (where R ...
DOI:
10.1126/science.1130895

14. Interface Mobility from Interface Random Walk

Author:
Trautt, Zachary T.; Upmanyu, Moneesh; Karma, Alain
Source:
Science 2006 v.314 no.5799 pp. 632-635
ISSN:
0036-8075
Subject:
diffusivity; interface phenomena; kinetics; models; monitoring; prediction
Abstract:
... Computational studies aimed at extracting interface mobilities require driving forces orders of magnitude higher than those occurring experimentally. We present a computational methodology that extracts the absolute interface mobility in the zero driving force limit by monitoring the one-dimensional random walk of the mean interface position along the interface normal. The method exploits a fluctu ...
DOI:
10.1126/science.1131988

15. Molecular Phylogeny and Evolution of Morphology in the Social Amoebas

Author:
Schaap, Pauline; Winckler, Thomas; Nelson, Michaela; Alvarez-Curto, Elisa; Elgie, Barrie; Hagiwara, Hiromitsu; Cavender, James; Milano-Curto, Alicia; Rozen, Daniel E.; Dingermann, Theodor; Mutzel, Rupert; Baldauf, Sandra L.
Source:
Science 2006 v.314 no.5799 pp. 661-663
ISSN:
0036-8075
Subject:
Dictyostelium discoideum; data collection; genes; models; phylogeny; ribosomal RNA; taxonomy
Abstract:
... The social amoebas (Dictyostelia) display conditional multicellularity in a wide variety of forms. Despite widespread interest in Dictyostelium discoideum as a model system, almost no molecular data exist from the rest of the group. We constructed the first molecular phylogeny of the Dictyostelia with parallel small subunit ribosomal RNA and a-tubulin data sets, and we found that dictyostelid taxo ...
DOI:
10.1126/science.1130670
PubMed:
17068267
PubMed Central:
PMC2173941

16. Odorant Receptor-Derived cAMP Signals Direct Axonal Targeting

Author:
Imai, Takeshi; Suzuki, Misao; Sakano, Hitoshi
Source:
Science 2006 v.314 no.5799 pp. 657-661
ISSN:
0036-8075
Subject:
axons; cAMP-dependent protein kinase; cyclic AMP; genetic engineering; mammals; odor compounds; odorant receptors; olfactory bulb; sensory neurons
Abstract:
... In mammals, odorant receptors (ORs) direct the axons of olfactory sensory neurons (OSNs) toward targets in the olfactory bulb. We show that cyclic adenosine monophosphate (cAMP) signals that regulate the expression of axon guidance molecules are essential for the OR-instructed axonal projection. Genetic manipulations of ORs, stimulatory G protein, cAMP-dependent protein kinase, and cAMP response e ...
DOI:
10.1126/science.1131794

17. The Economics of Information Security

Author:
Anderson, Ross; Moore, Tyler
Source:
Science 2006 v.314 no.5799 pp. 610-613
ISSN:
0036-8075
Subject:
economics; equipment; law enforcement; politics
Abstract:
... The economics of information security has recently become a thriving and fast-moving discipline. As distributed systems are assembled from machines belonging to principals with divergent interests, we find that incentives are becoming as important as technical design in achieving dependability. The new field provides valuable insights not just into "security" topics (such as bugs, spam, phishing, ...
DOI:
10.1126/science.1130992

18. The Phase-Dependent Infrared Brightness of the Extrasolar Planet υ Andromedae b

Author:
Harrington, Joseph; Hansen, Brad M.; Luszcz, Statia H.; Seager, Sara; Deming, Drake; Menou, Kristen; Cho, James Y.-K.; Richardson, L. Jeremy
Source:
Science 2006 v.314 no.5799 pp. 623-626
ISSN:
0036-8075
Subject:
heat; telescopes
Abstract:
... The star υ Andromedae is orbited by three known planets, the innermost of which has an orbital period of 4.617 days and a mass at least 0.69 that of Jupiter. This planet is close enough to its host star that the radiation it absorbs overwhelms its internal heat losses. Here, we present the 24-micrometer light curve of this system, obtained with the Spitzer Space Telescope. It shows a variation in ...
DOI:
10.1126/science.1133904

19. Thrice Out of Africa: Ancient and Recent Expansions of the Honey Bee, Apis mellifera

Author:
Whitfield, Charles W.; Behura, Susanta K.; Berlocher, Stewart H.; Clark, Andrew G.; Johnston, J. Spencer; Sheppard, Walter S.; Smith, Deborah R.; Suarez, Andrew V.; Weaver, Daniel; Tsutsui, Neil D.
Source:
Science 2006 v.314 no.5799 pp. 642-645
ISSN:
0036-8075
Subject:
Apis mellifera; alleles; genotyping; honey bees; indigenous species; introduced species; single nucleotide polymorphism; Africa; Eurasia; Western European region
Abstract:
... We characterized Apis mellifera in both native and introduced ranges using 1136 single-nucleotide polymorphisms genotyped in 341 individuals. Our results indicate that A. mellifera originated in Africa and expanded into Eurasia at least twice, resulting in populations in eastern and western Europe that are geographically close but genetically distant. A third expansion in the New World has involve ...
DOI:
10.1126/science.1132772

20. X-ray-Induced Dissociation of H₂O and Formation of an O₂-H₂ Alloy at High Pressure

Author:
Mao, Wendy L.; Mao, Ho-kwang; Meng, Yue; Eng, Peter J.; Hu, Michael Y.; Chow, Paul; Cai, Yong Q.; Shu, Jinfu; Hemley, Russell J.
Source:
Science 2006 v.314 no.5799 pp. 636-638
ISSN:
0036-8075
Subject:
Raman spectroscopy; X-radiation; X-ray diffraction; alloys; hydrogen; ice; oxygen; superoxide anion; temperature
Abstract:
... When subjected to high pressure and extensive x-radiation, water (H₂O) molecules cleaved, forming O-O and H-H bonds. The oxygen (O) and hydrogen (H) framework in ice VII was converted into a molecular alloy of O₂ and H₂. X-ray diffraction, x-ray Raman scattering, and optical Raman spectroscopy demonstrated that this crystalline solid differs from previously known phases. It remained stable with re ...
DOI:
10.1126/science.1132884