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We have assembled CO2 emission figures from collections of urban GHG emission estimates published in peer-reviewed journals or reports from research institutes and non-governmental organizations. Analyzing the scaling with population size, we find that the exponent is development dependent with a transition from super- to sub-linear scaling. From the climate change mitigation point of view, the results suggest that urbanization is desirable in developed countries. Further, we compare this analysis with a second scaling relation, namely the fundamental allometry between city population and area, and propose that density might be a decisive quantity too. Last, we derive the theoretical country-wide urban emissions by integration and obtain a dependence on the size of the largest city.

The strong gravitational field of a black hole has distinct effects on the observed profile of a spectral line from an accretion disc near a black hole. The observed profile of the spectral line is broadened and skewed by a fast orbital motion and redshifted by a gravitational field. These effects can help us to constrain the parameters of a system with a black hole, both in active galactic nuclei and in a stellar-mass black hole. Here we explore the fact that an accretion disc emission can be mathematically imagined as a superposition of radiating accretion rings that extend from the inner edge to the outer rim of the disc, with some radially varying emissivity. In our work, we show that a characteristic double-horn profile of several radially confined (relatively narrow) accretion rings or belts could be recognized by the planned instruments onboard future satellites (such as the proposed ESA Large Observatory for X-ray Timing).

The correlations between the electric dipole polarizability and neutron skin thickness are studied by the
magic nuclei 40,48Ca, 68,78Ni, 132Sn, and 208Pb. The strength distribution of the E1 transitions is calculated
within the random phase approximation model based on the Skyrme nuclear energy density functional.
A comparison with the experimental data has allowed us to constrain the value of the nuclear symmetry
energy J = 30–37 MeV.

Intro -- Contents -- Acknowledgments -- Dedication -- About the Author -- Acronyms -- Preface -- 1: Suborbital Flight: A Primer -- Early Suborbital Flights -- Russian Suborbital Flights -- Ham and the Astrocats -- Mercury Program: Manned Suborbital Flights 1 and 2 -- X-15: Manned Suborbital Flights 3 and 4 -- The April 5 Anomaly: Manned Suborbital Flight #5 -- The Legacy of SpaceShipOne: Manned Suborbital Flights 6, 7, and 8 -- Notes -- 2: Revolution through Competition -- The Orteig Prize -- Peter Diamandis -- Richard Branson -- Ansari X-Prize: Building a Suborbital Spirit of St. Louis -- Da Vinci -- Advent -- Orizont -- Thunderbird -- Cosmopolis -- Condor-X -- Scaled composites -- Paul Allen -- Notes -- 3: SpaceShipOne -- Burt Rutan -- The space bug -- SpaceShipOne Construction -- Propulsion -- Inside SpaceShipOne -- WhiteKnight -- SpaceShipOne Test Flights -- Launch to landing -- Mission Control -- Test Flights -- WhiteKnight/SpaceShipOne flight tests [2, 3] -- Flight 24C/01C: first captive carry -- Flight 29C/02C: first manned captive carry flight of SpaceShipOne -- Flight 30L/03G: first glide flight of SpaceShipOne -- Flight 31LC/04GC: second glide flight of SpaceShipOne I (aborted) -- Flight 32L/05G: second glide flight of SpaceShipOne (second attempt) -- Flight 37L/06G: third glide flight of SpaceShipOne -- Flight 38L/07G: fourth glide flight of SpaceShipOne -- Flight 40L/08G: fifth glide flight of SpaceShipOne -- Flight 41L/09G: abort contingency assessment -- Flight 42L/10G: seventh glide flight and propulsion system check -- Flight 43L/11P: supersonic flight/first powered flight -- Flight 49L/12G: twelfth flight of SpaceShipOne/unpowered glide test -- Show-stopping tortoises -- Flight 53L/13P: second powered flight/transonic-supersonic handling -- Flight 56L/14P: third powered flight/supersonic feather stability and control.

[Background] Reactions with stable beams have demonstrated a strong interplay between nuclear structure and fusion. Exotic beam facilities open new perspectives to understand the impact of neutron skin, large isospin, and weak binding energies on fusion. Microscopic theories of fusion are required to guide future experiments. [Purpose] To investigate new effects of exotic structures and dynamics in near-barrier fusion with exotic nuclei. [Method] Microscopic approaches based on the Hartree-Fock (HF) mean-field theory are used for studying fusion barriers in $^{40-54}$Ca+$^{116}$Sn reactions for even isotopes. Bare potential barriers are obtained assuming frozen HF ground-state densities. Dynamical effects on the barrier are accounted for in time-dependent Hartree-Fock (TDHF) calculations of the collisions. Vibrational couplings are studied in the coupled-channel framework and near-barrier nucleon transfer is investigated with TDHF calculations. [Results] The development of a neutron skin in exotic calcium isotopes strongly lowers the bare potential barrier. However, this static effect is not apparent when dynamical effects are included. On the contrary, a fusion hindrance is observed in TDHF calculations with the most neutron rich calcium isotopes which cannot be explained by vibrational couplings. Transfer reactions are also important in these systems due to charge equilibration processes. [Conclusions] Despite its impact on the bare potential, the neutron skin is not seen as playing an important role in the fusion dynamics. However, the charge transfer with exotic projectiles could lead to an increase of the Coulomb repulsion between the fragments, suppressing fusion. The effect of transfer and dissipative mechanisms on fusion with exotic nuclei deserve further studies. ; The authors are grateful to M. Dasgupta, D. J. Hinde, and A. S. Umar for stimulating discussions during this work. This research was undertaken with the assistance of resources from the National Computational Infrastructure (NCI), which is supported by the Australian Government. This research was supported under Australian Research Council's Future Fellowship (Project No. FT120100760), Discovery Projects (Project No. DP140101337), and Laureate Fellowship (Project No. FL110100098) funding schemes.

This short presentation will update my more than 25 years long attempts at understanding<br />the actions of the Central Engine at our Galactic Center.

Galaxies with stellar masses near M* contain the majority of stellar mass in the universe, and are therefore of special interest in the study of galaxy evolution. The Milky Way (MW) and Andromeda (M31) have present-day stellar masses near M*, at 5 x 10(10) M-circle dot (defined here to be MW-mass) and 10(11) M-circle dot (defined to be M31-mass). We study the typical progenitors of these galaxies using the FOURSTAR Galaxy Evolution Survey (ZFOURGE). ZFOURGE is a deep medium-band near-IR imaging survey, which is sensitive to the progenitors of these galaxies out to z similar to 3. We use abundance-matching techniques to identify the main progenitors of these galaxies at higher redshifts. We measure the evolution in the stellar mass, rest-frame colors, morphologies, far-IR luminosities, and star formation rates, combining our deep multiwavelength imaging with near-IR Hubble Space Telescope imaging from Cosmic Near-IR Deep Extragalactic Legacy Survey (CANDELS), and Spitzer and Herschel far-IR imaging from Great Observatories Origins Deep Survey-Herschel and CANDELS-Herschel. The typical MW-mass and M31-mass progenitors passed through the same evolution stages, evolving from blue, star-forming disk galaxies at the earliest stages to redder dust-obscured IR-luminous galaxies in intermediate stages and to red, more quiescent galaxies at their latest stages. The progenitors of the MW-mass galaxies reached each evolutionary stage at later times (lower redshifts) and with stellar masses that are a factor of two to three lower than the progenitors of the M31-mass galaxies. The process driving this evolution, including the suppression of star formation in present-day M* galaxies, requires an evolving stellar-mass/halo-mass ratio and/or evolving halo-mass threshold for quiescent galaxies. The effective size and SFRs imply that the baryonic cold-gas fractions drop as galaxies evolve from high redshift to z similar to 0 and are strongly anticorrelated with an increase in the Sersic index. Therefore, the growth of galaxy bulges in M* galaxies corresponds to a rapid decline in the galaxy gas fractions and/or a decrease in the star formation efficiency. ; National Science Foundation AST-1009707, AST-0808133 ; ERC HIGHZ 227749 ; NL-NWO Spinoza ; NASA NAS5-26555 ; HST program GO-12060 ; National Collaborative Research Infrastructure Strategy of the Australian Federal Government ; Texas A&M University ; George P. and Cynthia Woods Institute for Fundamental Physics and Astronomy ; Astronomy

À côté du marché et de la hiérarchie, la coopération s'impose comme un mode de coordination de l'activité économique. Les autorités algériennes, souhaitant relancer l'artisanat, s'orientent vers la création de Nuclei, regroupement d'entreprises qui se réunissent périodiquement autour d'un animateur afin d'identifier leurs problèmes communs et de trouver ensemble des solutions. L'article analyse comment les Nuclei d'entreprises peuvent créer du capital social et redynamiser un territoire.

An analysis of the data that have recently become available from observing campaigns, including VLA, VLBA, and satellite instruments, shows some remarkable similarities and significant differences in the data from some epochs of galactic microquasars, including GRS 1915+105, the concurrent radio and X-ray data [3] on Centaurus A (NGC 5128), 3C120 [35], and 3C454.3 as reported by Bonning et al. [16], which showed the first results from the Fermi Space Telescope for the concurrent variability at optical, UV, IR, and g-ray variability of that source. In combination with observations from microquasars and quasars from the MOJAVE Collaboration [32], these data provide time-dependent evolutions of radio data at mas (i.e., parsec for AGNs, and Astronomical Unit scales for microquasars). These sources all show a remarkable richness of patterns of variability for astrophysical jets across the entire electromagnetic spectrum. It is likely that these patterns of variability arise from the complex structures through which the jets propagate, but it is also possible that the jets constitution, initial energy, and collimation have significant observational consequences. On the other hand, Ulrich et al. [42] suggest that this picture is complicated for radio-quiet AGN by the presence of significant emission from accretion disks in those sources. Consistent with the jet-ambient-medium hypothesis, the observed concurrent radio and X-ray variability of Centaurus A [3] could have been caused by the launch of a jet element from Cen A's central source and that jet's interaction with the interstellar medium in the core region of that galaxy.

We present maps for the electron temperature in the inner kpc of three luminous Seyfert galaxies: Mrk 79, Mrk 348, and Mrk 607 obtained from Gemini Multi-Object Spectrograph-integral field unit observations at spatial resolutions of ∼110–280 pc. We study the distributions of electron temperature in active galaxies and find temperatures varying in the range from ∼8000 to ≳30000K. Shocks due to gas outflows play an important role in the observed temperature distributions of Mrk 79 and Mrk 348, while standard photoionization models reproduce the derived temperature values for Mrk 607. In Mrk 79 and Mrk 348, we find direct evidence for shock ionization with overall orientation orthogonal to the ionization axis, where shocks can be easily observed as the active galactic nuclei radiation field is shielded by the nuclear dusty torus. This also indicates that even when the ionization cones are narrow, the shocks can be much wider angle. © 2020 The Author(s). ; This study was financed in part by CNPq, FAPERGS, and FAPESP. AF acknowledges the support from grant PRIN MIUR2017-20173ML3WW−001. EPM acknowledges financial support from the project 'Estallidos6' AYA2016-79724-C4. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the NationalScience Foundation (United States), National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), Ministério da Ciência, Tecnologia e Inovação (Brazil), and Korea Astronomy and Space Science Institute (Republic of Korea). ; With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709. ; Peer reviewed