192 research outputs found
Effect of Rumensin on legume bloat in cattle
Rumensin with or without Bloatguard was fed to rumen-fistulated cattle grazing lush alfalfa pasture. Although Rumensin alone or in combination with low doses of Bloatguard reduced bloat, it was not completely effective. Hence, Bloatguard at the recommended dose is still necessary for full bloat control
Gamma-Ray Burst Spectra and Time Histories from 2 to 400 keV
The Gamma-Ray burst detector on Ginga consisted of a proportional counter to
observe the x-rays and a scintillation counter to observe the gamma-rays. It
was ideally suited to study the x-rays associated with gamma-ray bursts (GRBs).
Ginga detected 120 GRBs and 22 of them had sufficient statistics to determine
spectra from 2 to 400 keV. Although the Ginga and BATSE trigger criteria were
very similar, the distribution of spectral parameters was different. Ginga
observed bend energies in the spectra down to 2 keV and had a larger fraction
of bursts with low energy power law indexes greater than zero. The average
ratio of energy in the x-ray band (2 to 10 keV) compared to the gamma-ray band
(50 to 300 keV) was 24%. Some events had more energy in the x-ray band than in
the gamma-ray band. One Ginga event had a period of time preceding the gamma
rays that was effectively pure x-ray emission. This x-ray ``preactivity'' might
be due to the penchant for the GRB time structure to be broader at lower energy
rather than a different physical process. The x-rays tend to rise and fall
slower than the gamma rays but they both tend to peak at about the same time.
This argues against models involving the injection of relativistic electrons
that cool by synchrotron radiation.Comment: 5 pages, 3 embedded figures, latex, to appear in Nuclear Physics B
Proceedings, eds L. Scarsi, et a
Challenges of open innovation: the paradox of firm investment in open-source software
Open innovation is a powerful framework encompassing the generation, capture, and employment of intellectual property at the firm level. We identify three fundamental challenges for firms in applying the concept of open innovation: finding creative ways to exploit internal innovation, incorporating external innovation into internal development, and motivating outsiders to supply an ongoing stream of external innovations. This latter challenge involves a paradox, why would firms spend money on R&D efforts if the results of these efforts are available to rival firms? To explore these challenges, we examine the activity of firms in opensource software to support their innovation strategies. Firms involved in open-source software often make investments that will be shared with real and potential rivals. We identify four strategies firms employ – pooled R&D/product development, spinouts, selling complements and attracting donated complements – and discuss how they address the three key challenges of open innovation. We conclude with suggestions for how similar strategies may apply in other industries and offer some possible avenues for future research on open innovation
Caustic ingestion management: world society of emergency surgery preliminary survey of expert opinion
[This corrects the article DOI: 10.1186/s13017-015-0043-4.].sem informação1056sem informaçãosem informaçã
The chemical enrichment of the ICM from hydrodynamical simulations
The study of the metal enrichment of the intra-cluster and inter-galactic
media (ICM and IGM) represents a direct means to reconstruct the past history
of star formation, the role of feedback processes and the gas-dynamical
processes which determine the evolution of the cosmic baryons. In this paper we
review the approaches that have been followed so far to model the enrichment of
the ICM in a cosmological context. While our presentation will be focused on
the role played by hydrodynamical simulations, we will also discuss other
approaches based on semi-analytical models of galaxy formation, also critically
discussing pros and cons of the different methods. We will first review the
concept of the model of chemical evolution to be implemented in any
chemo-dynamical description. We will emphasise how the predictions of this
model critically depend on the choice of the stellar initial mass function, on
the stellar life-times and on the stellar yields. We will then overview the
comparisons presented so far between X-ray observations of the ICM enrichment
and model predictions. We will show how the most recent chemo-dynamical models
are able to capture the basic features of the observed metal content of the ICM
and its evolution. We will conclude by highlighting the open questions in this
study and the direction of improvements for cosmological chemo-dynamical models
of the next generation.Comment: 25 pages, 11 figures, accepted for publication in Space Science
Reviews, special issue "Clusters of galaxies: beyond the thermal view",
Editor J.S. Kaastra, Chapter 18; work done by an international team at the
International Space Science Institute (ISSI), Bern, organised by J.S.
Kaastra, A.M. Bykov, S. Schindler & J.A.M. Bleeke
Transnational partisanship: idea and practice
That parties might successfully organize transnationally is an idea often met with scepticism. This article argues that while certain favourable conditions are indeed absent in the transnational domain, this implies not that partisanship is impossible but that it is likely to be marked by certain traits. Specifically, it will tend to be episodic, structured as a low-density network and delocalized in its ideational content. These tendencies affect the normative expectations one can attach to it. Transnational partisanship should be valued as a transitional phenomenon, e.g. as a pathway to transnational democracy, more than as a desirable thing in itself
Effect of Interlaminar Epidural Steroid Injection in Acute and Subacute Pain Due to Lumbar Disk Herniation: A Randomized Comparison of 2 Different Protocols
In order to assess the efficacy of epidural steroid injections (ESI) in acute and subacute pain due to lumbar spine disk herniation, we conducted a randomized trial, comparing 2 different protocols. Fourty patients with radicular pain due to L4-L5 and L5-S1 disc herniation were assigned to receive either 3 consecutive ESI every 24 hours through a spinal catheter (group A) or 3 consecutive ESI every 10 days with an epidural needle (group B). All patients had improved Oswestry Disabilty Index (ODI) and the Visual Analog Scale (VAS) for pain scores at 1 month of follow-up compared to baseline, while no significant differences were observed between the 2 groups. The scores for group B were statistically significant lower at 2 months of follow-up compared to those of group A. The improvement in the scores of group B was continuous since the mean scores at 2 months of follow up were lower compared to the respective scores at 1 month. Protocol B (3 consecutive ESI every 10 days) was found more effective in the treatment of subacute pain compared to Protocol A (3 consecutive ESI every 24 hours) with statistically significant differences in the ODI and VAS scores at 2 months of follow-up
Protest Cycles and Political Process: American Peace Movements in the Nuclear Age
Since the dawn of the nuclear age small groups of activists have consistently protested both the content of United States national security policy, and the process by which it is made. Only occasionally, however, has concern about nuclear weapons spread beyond these relatively marginal groups, generated substantial public support, and reached mainstream political institutions. In this paper, I use histories of peace protest and analyses of the inside of these social movements and theoretical work on protest cycles to explain cycles of movement engagement and quiescence in terms of their relation to external political context, or the "structure of political opportunity." I begin with a brief review of the relevant literature on the origins of movements, noting parallels in the study of interest groups. Building on recent literature on political opportunity structure, I suggest a theoretical framework for understanding the lifecycle of a social movement that emphasizes the interaction between activist choices and political context, proposing a six-stage process through which challenging movements develop. Using this theoretical framework I examine the four cases of relatively broad antinuclear weapons mobilization in postwar America. I conclude with a discussion of movement cycles and their relation to political alignment, public policy, and institutional politics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68552/2/10.1177_106591299304600302.pd
Perturbations of brane worlds
We consider cosmological models where the universe, governed by Einstein's
equations, is a piece of a five dimensional double-sided anti-de Sitter
spacetime (that is, a "-symmetric bulk") with matter confined to its four
dimensional Robertson-Walker boundary or "brane". We study the perturbations of
such models. We use conformally minkowskian coordinates to disentangle the
contributions of the bulk gravitons and of the motion of the brane. We find the
restrictions put on the bulk gravitons when matter on the brane is taken to be
a scalar field and we solve in that case the brane perturbation equations.Comment: 19 pages, no figures, RevTex, version to appear in Phys.Rev.D; minor
changes in chap.V, polarisation tensor at page 13 correcte
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