Cosmic Star Formation History to z=1 from a Narrow Emission Line Selected Tunable Filter Survey

We report the results of a deep 3D imaging survey of the Hubble Deep Field North using the Taurus Tunable Filter and the William Herschel Telescope. This survey was designed to search for new line emitting populations of objects missed by other techniques and to measure the cosmic star-formation rate density from a line-selected survey. We observed in three contiguous sequences of narrow band slices in the 7100, 8100 and 9100A regions of the spectrum, corresponding to a cosmological volume of up to 1000 Mpc^3 at z=1, down to a flux limit of 2x 10^-17 ergs cm^-2 s^-1. The survey is deep enough to be highly complete for low line luminosity galaxies. Cross-matching with existing spectroscopy in the field results in a small line-luminosity limited sample, with very highly redshift identification completeness containing seven [OII], Hbeta and Halpha emitters over the redshift range 0.3 - 0.9. Treating this as a direct star-formation rate selected sample we estimate the star-formation history of the Universe to z=1. We find no evidence for any new population of line emitting objects contributing significantly to the cosmological star-formation rate density. Rather from our complete narrow-band sample we find the star-formation history is consistent with earlier estimates from broad-band imaging surveys and other less deep line-selected surveys.Comment: 12 pages, 3 figures. ApJ in press (Dec 2004

Measurements of the Cosmic Ray Composition with Air Shower Experiments

In this paper we review air shower data related to the mass composition of cosmic rays above 10$^{15}$ eV. After explaining the basic relations between air shower observables and the primary mass and energy of cosmic rays, we present different approaches and results of composition studies with surface detectors. Furthermore, we discuss measurements of the longitudinal development of air showers from non-imaging Cherenkov detectors and fluorescence telescopes. The interpretation of these experimental results in terms of primary mass is highly susceptible to the theoretical uncertainties of hadronic interactions in air showers. We nevertheless attempt to calculate the logarithmic mass from the data using different hadronic interaction models and to study its energy dependence from 10$^{15}$ to 10$^{20}$ eV.Comment: 21 pages, invited review accepted for publication in Astroparticle Physics, Topical Issue on Cosmic Ray

The role of soil carbon in natural climate solutions

Acknowledgements. This study was made possible by funding from the Craig and Susan McCaw Foundation. Data Deposition A global spatial dataset of reforestation opportunities is available on Zenodo (https://zenodo.org/record/883444). Figures 1 and 2 have associated raw data that can be made available upon request.Peer reviewedPostprin

New Method for Estimation of Aeolian Sand Transport Rate Using Ceramic Sand Flux Sensor (UD-101)

In this study, a new method for the estimation of aeolian sand transport rate was developed; the method employs a ceramic sand flux sensor (UD-101). UD-101 detects wind-blown sand impacting on its surface. The method was devised by considering the results of wind tunnel experiments that were performed using a vertical sediment trap and the UD-101. Field measurements to evaluate the estimation accuracy during the prevalence of unsteady winds were performed on a flat backshore. The results showed that aeolian sand transport rates estimated using the developed method were of the same order as those estimated using the existing method for high transport rates, i.e., for transport rates greater than 0.01 kg m−1 s−1

Mary's Powers of Imagination

One common response to the knowledge argument is the ability hypothesis. Proponents of the ability hypothesis accept that Mary learns what seeing red is like when she exits her black-and-white room, but they deny that the kind of knowledge she gains is propositional in nature. Rather, she acquires a cluster of abilities that she previously lacked, in particular, the abilities to recognize, remember, and imagine the color red. For proponents of the ability hypothesis, knowing what an experience is like simply consists in the possession of these abilities. Criticisms of the ability hypothesis tend to focus on this last claim. Such critics tend to accept that Mary gains these abilities when she leaves the room, but they deny that such abilities constitute knowledge of what an experience is like. To my mind, however, this critical strategy grants too much. Focusing specifically on imaginative ability, I argue that Mary does not gain this ability when she leaves the room for she already had the ability to imagine red while she was inside it. Moreover, despite what some have thought, the ability hypothesis cannot be easily rescued by recasting it in terms of a more restrictive imaginative ability. My purpose here is not to take sides in the debate about physicalism, i.e., my criticism of the ability hypothesis is not offered in an attempt to defend the anti-physicalist conclusion of the knowledge argument. Rather, my purpose is to redeem the imagination from the misleading picture of it that discussion of the knowledge argument has fostered

Grounding, Analysis, and Russellian Monism

Few these days dispute that the knowledge argument demonstrates an epistemic gap between the physical facts and the facts about experience. It is much more contentious whether that epistemic gap can be used to demonstrate a metaphysical gap of a kind that is inconsistent with physicalism. In this paper I will explore two attempts to block the inference from an epistemic gap to a metaphysical gap – the first from the phenomenal concept strategy, the second from Russellian monism – and suggest how the proponent of the knowledge argument might respond to each of these challenges. In doing so, I will draw on recent discussions of grounding and essence in the metaphysics literature

Cosmic Rays from the Knee to the Highest Energies

This review summarizes recent developments in the understanding of high-energy cosmic rays. It focuses on galactic and presumably extragalactic particles in the energy range from the knee (10^15 eV) up to the highest energies observed (>10^20 eV). Emphasis is put on observational results, their interpretation, and the global picture of cosmic rays that has emerged during the last decade.Comment: Invited review, submitted to Progress in Particle and Nuclear Physic

Search for Dark Matter Annihilation in the Galactic Center with IceCube-79

The Milky Way is expected to be embedded in a halo of dark matter particles, with the highest density in the central region, and decreasing density with the halo-centric radius. Dark matter might be indirectly detectable at Earth through a flux of stable particles generated in dark matter annihilations and peaked in the direction of the Galactic Center. We present a search for an excess flux of muon (anti-) neutrinos from dark matter annihilation in the Galactic Center using the cubic-kilometer-sized IceCube neutrino detector at the South Pole. There, the Galactic Center is always seen above the horizon. Thus, new and dedicated veto techniques against atmospheric muons are required to make the southern hemisphere accessible for IceCube. We used 319.7 live-days of data from IceCube operating in its 79-string configuration during 2010 and 2011. No neutrino excess was found and the final result is compatible with the background. We present upper limits on the self-annihilation cross-section, \left, for WIMP masses ranging from 30 GeV up to 10 TeV, assuming cuspy (NFW) and flat-cored (Burkert) dark matter halo profiles, reaching down to $\simeq 4 \cdot 10^{-24}$ cm$^3$ s$^{-1}$, and $\simeq 2.6 \cdot 10^{-23}$ cm$^3$ s$^{-1}$ for the $\nu\overline{\nu}$ channel, respectively.Comment: 14 pages, 9 figures, Submitted to EPJ-C, added references, extended limit overvie

Biomechanical comparison of screw-based zoning of PHILOS and Fx proximal humerus plates

Background Treatment of proximal humerus fractures with locking plates is associated with complications. We aimed to compare the biomechanical effects of removing screws and blade of a fixed angle locking plate and hybrid blade plate, on a two-part fracture model. Methods Forty-five synthetic humeri were divided into nine groups where four were implanted with a hybrid blade plate and the remaining with locking plate, to treat a two-part surgical neck fracture. Plates’ head screws and blades were divided into zones based on their distance from fracture site. Two groups acted as a control for each plate and the remaining seven had either a vacant zone or blade swapped with screws. For elastic cantilever bending, humeral head was fixed and the shaft was displaced 5 mm in extension, flexion, valgus and varus direction. Specimens were further loaded in varus direction to investigate their plastic behaviour. Results In both plates, removal of inferomedial screws or blade led to a significantly larger drop in varus construct stiffness than other zones. In blade plate, insertion of screws in place of blade significantly increased the mean extension, flexion valgus and varus bending stiffness (24.458%/16.623%/19.493%/14.137%). In locking plate, removal of screw zones proximal to the inferomedial screws reduced extension and flexion bending stiffness by 26–33%. Conclusions Although medial support improved varus stability, two inferomedial screws were more effective than blade. Proximal screws are important for extension and flexion. Mechanical consequences of screw removal should be considered when deciding the number and choice of screws and blade in clinic

A call for transparent reporting to optimize the predictive value of preclinical research

The US National Institute of Neurological Disorders and Stroke convened major stakeholders in June 2012 to discuss how to improve the methodological reporting of animal studies in grant applications and publications. The main workshop recommendation is that at a minimum studies should report on sample-size estimation, whether and how animals were randomized, whether investigators were blind to the treatment, and the handling of data. We recognize that achieving a meaningful improvement in the quality of reporting will require a concerted effort by investigators, reviewers, funding agencies and journal editors. Requiring better reporting of animal studies will raise awareness of the importance of rigorous study design to accelerate scientific progress