Institution
University of California, Santa Cruz
Education•Santa Cruz, California, United States•
About: University of California, Santa Cruz is a education organization based out in Santa Cruz, California, United States. It is known for research contribution in the topics: Galaxy & Population. The organization has 15541 authors who have published 44120 publications receiving 2759983 citations. The organization is also known as: UCSC & UC, Santa Cruz.
Topics: Galaxy, Population, Star formation, Redshift, Planet
Papers published on a yearly basis
Papers
More filters
••
TL;DR: In this review, recent findings are surveyed to illustrate that protein fibrillogenesis requires a partially folded conformation, which is relatively unfolded, and shares many structural properties with the pre-molten globule state.
1,014 citations
••
TL;DR: In this article, the authors presented improved synthesis models of the evolving spectrum of the UV/X-ray diffuse background, updating and extending their previous results, and provided tables of predicted H I and He II photoionization and photoheating rates for use, e.g., in cosmological hydrodynamics simulations of the Lyα forest and a new metallicity-dependent calibration to the UV luminosity density-star formation rate density relation.
Abstract: We present improved synthesis models of the evolving spectrum of the UV/X-ray diffuse background, updating and extending our previous results. Five new main components are added to our radiative transfer code CUBA: (1) the sawtooth modulation of the background intensity from resonant line absorption in the Lyman series of cosmic hydrogen and helium; (2) the X-ray emission from the obscured and unobscured quasars that gives origin to the X-ray background; (3) a piecewise parameterization of the distribution in redshift and column density of intergalactic absorbers that fits recent measurements of the mean free path of 1 ryd photons; (4) an accurate treatment of the photoionization structure of absorbers, which enters in the calculation of the helium continuum opacity and recombination emissivity; and (5) the UV emission from star-forming galaxies at all redshifts. We provide tables of the predicted H I and He II photoionization and photoheating rates for use, e.g., in cosmological hydrodynamics simulations of the Lyα forest and a new metallicity-dependent calibration to the UV luminosity density-star formation rate density relation. A "minimal cosmic reionization model" is also presented in which the galaxy UV emissivity traces recent determinations of the cosmic history of star formation, the luminosity-weighted escape fraction of hydrogen-ionizing radiation increases rapidly with look-back time, the clumping factor of the high-redshift intergalactic medium evolves following the results of hydrodynamic simulations, and Population III stars and miniquasars make a negligible contribution to the metagalactic flux. The model provides a good fit to the hydrogen-ionization rates inferred from flux decrement and proximity effect measurements, predicts that cosmological H II (He III) regions overlap at redshift 6.7 (2.8), and yields an optical depth to Thomson scattering, τes = 0.084 that is in agreement with Wilkinson Microwave Anisotropy Probe results. Our new background intensities and spectra are sensitive to a number of poorly determined input parameters and suffer from various degeneracies. Their predictive power should be constantly tested against new observations. We are therefore making our redshift-dependent UV/X emissivities and CUBA outputs freely available for public use at http://www.ucolick.org/~pmadau/CUBA.
1,010 citations
••
TL;DR: It is shown that in addition to its functions during flower development, AP2 activity is also required during seed development, and this suggests that AP2 represents a new class of plant regulatory proteins that may play a general role in the control of Arabidopsis development.
Abstract: APETALA2 (AP2) plays a central role in the establishment of the floral meristem, the specification of floral organ identity, and the regulation of floral homeotic gene expression in Arabidopsis. We show here that in addition to its functions during flower development, AP2 activity is also required during seed development. We isolated the AP2 gene and found that it encodes a putative nuclear protein that is distinguished by an essential 68-amino acid repeated motif, the AP2 domain. Consistent with its genetic functions, we determined that AP2 is expressed at the RNA level in all four types of floral organs--sepals, petals, stamens, and carpels--and in developing ovules. Thus, AP2 gene transcription does not appear to be spatially restricted by the floral homeotic gene AGAMOUS as predicted by previous studies. We also found that AP2 is expressed at the RNA level in the inflorescence meristem and in nonfloral organs, including leaf and stem. Taken together, our results suggest that AP2 represents a new class of plant regulatory proteins that may play a general role in the control of Arabidopsis development.
1,008 citations
••
University of Arizona1, Yale University2, University of California, Santa Barbara3, Natural Resources Research Institute4, Colorado State University5, Carnegie Institution for Science6, University of California, Santa Cruz7, University of Nevada, Las Vegas8, Texas Tech University9, University of Tennessee10, University of New Mexico11, University of Buenos Aires12, University of California, Berkeley13, Northern Arizona University14, Columbia University15, University of Colorado Boulder16, University of Wyoming17
TL;DR: It is shown that RUE decreases across biomes as mean annual precipitation increases, and during the driest years at each site, there is convergence to a common maximum RUE (RUEmax) that is typical of arid ecosystems.
Abstract: Water availability limits plant growth and production in almost all terrestrial ecosystems. However, biomes differ substantially in sensitivity of aboveground net primary production (ANPP) to between-year variation in precipitation. Average rain-use efficiency (RUE; ANPP/precipitation) also varies between biomes, supposedly because of differences in vegetation structure and/or biogeochemical constraints. Here we show that RUE decreases across biomes as mean annual precipitation increases. However, during the driest years at each site, there is convergence to a common maximum RUE (RUE(max)) that is typical of arid ecosystems. RUE(max) was also identified by experimentally altering the degree of limitation by water and other resources. Thus, in years when water is most limiting, deserts, grasslands and forests all exhibit the same rate of biomass production per unit rainfall, despite differences in physiognomy and site-level RUE. Global climate models predict increased between-year variability in precipitation, more frequent extreme drought events, and changes in temperature. Forecasts of future ecosystem behaviour should take into account this convergent feature of terrestrial biomes.
1,005 citations
••
Max Planck Society1, Leiden University2, Yale University3, Goddard Space Flight Center4, Space Telescope Science Institute5, University of Michigan6, University of California, Santa Cruz7, Colby College8, University of Oxford9, University of Hertfordshire10, Hebrew University of Jerusalem11, University of Wisconsin-Madison12, Open University13, Carnegie Institution for Science14, University of Kentucky15
TL;DR: In this paper, the galaxy size-mass distribution over the redshift range 0 3 × 10{sup 9} M {sub ☉}, and steep, R{sub eff}∝M{sub ∗}{sup 0.75}, for early-type galaxies with stellar mass > 2 × 10,sup 10} M{sub ǫ, and the intrinsic scattermore is ≲0.2 dex for all galaxy types and redshifts.
Abstract: Spectroscopic+photometric redshifts, stellar mass estimates, and rest-frame colors from the 3D-HST survey are combined with structural parameter measurements from CANDELS imaging to determine the galaxy size-mass distribution over the redshift range 0 3 × 10{sup 9} M {sub ☉}, and steep, R{sub eff}∝M{sub ∗}{sup 0.75}, for early-type galaxies with stellar mass >2 × 10{sup 10} M {sub ☉}. The intrinsic scattermore » is ≲0.2 dex for all galaxy types and redshifts. For late-type galaxies, the logarithmic size distribution is not symmetric but is skewed toward small sizes: at all redshifts and masses, a tail of small late-type galaxies exists that overlaps in size with the early-type galaxy population. The number density of massive (∼10{sup 11} M {sub ☉}), compact (R {sub eff} < 2 kpc) early-type galaxies increases from z = 3 to z = 1.5-2 and then strongly decreases at later cosmic times.« less
1,004 citations
Authors
Showing all 15733 results
Name | H-index | Papers | Citations |
---|---|---|---|
David J. Schlegel | 193 | 600 | 193972 |
David R. Williams | 178 | 2034 | 138789 |
John R. Yates | 177 | 1036 | 129029 |
David Haussler | 172 | 488 | 224960 |
Evan E. Eichler | 170 | 567 | 150409 |
Anton M. Koekemoer | 168 | 1127 | 106796 |
Mark Gerstein | 168 | 751 | 149578 |
Alexander S. Szalay | 166 | 936 | 145745 |
Charles M. Lieber | 165 | 521 | 132811 |
Jorge E. Cortes | 163 | 2784 | 124154 |
M. Razzano | 155 | 515 | 106357 |
Lars Hernquist | 148 | 598 | 88554 |
Aaron Dominguez | 147 | 1968 | 113224 |
Taeghwan Hyeon | 139 | 563 | 75814 |
Garth D. Illingworth | 137 | 505 | 61793 |