9,219 research outputs found
No relationship between fecundity and annual reproductive rate in bony fish
Background. There is still a widespread notion that bony fishes with high fecundities
are more productive and therefore more resistant to overexploitation. The purpose of
this study was to formally explore the relationship between fecundity and reproductive
success expressed as maximum annual reproductive rate, i.e. the number of new
spawners produced by existing spawners at low population densities.
Material and methods. We used maximum annual reproductive rate from a recent
study covering 49 species of bony fish; we used fecundity estimates from the published
literature.
Results. We found no significant relationship between fecundity (ranging from 368 to
10 million eggs) and maximum annual reproductive rate (ranging from 0.4 to 13.5
replacement spawners).
Conclusion. Fecundity in oviparous bony fish without parental care has no relation with
reproductive success. Apparently high fecundity in bony fish has evolved to counterbalance
pre-adult mortality, as indicated by the fact that variance in fecundity is 3 orders
of magnitude larger than variance in annual reproductive rate
The qualitative shift in European integration: towards permanent wage pressures and a \u2018Latin-Americanization\u2019 of Europe?
Forst on Reciprocity of Reasons: a Critique
According to Rainer Forst, (i) moral and political claims must meet a requirement of reciprocal and general acceptability (RGA) while (ii) we are under a duty in engaged discursive practice to justify such claims to others, or be able to do so, on grounds that meet RGA. The paper critically engages this view. I argue that Forst builds a key component of RGA, i.e., reciprocity of reasons, on an idea of the reasonable that undermines both (i) and (ii): if RGA builds on this idea, RGA is viciously regressive and a duty of justification to meet RGA fails to be agent transparent. This negative result opens the door for alternative conceptions of reciprocity and generality. I then suggest that a more promising conception of reciprocity and generality needs to build on an idea of the reasonable that helps to reconcile the emancipatory or protective aspirations of reciprocal and general justification with its egalitarian commitments. But this requires to downgrade RGA in the order of justification and to determine on prior, substantive grounds what level of discursive influence in reciprocal and general justification relevant agents ought to have
Monopoles in Real Time for Classical U(1) Gauge Field Theory
U(1) gauge fields are decomposed into a monopole and photon part across the
phase transition from the confinement to the Coulomb phase. We analyze the
leading Lyapunov exponents of such gauge field configurations on the lattice
which are initialized by quantum Monte Carlo simulations. We observe that the
monopole field carries the same Lyapunov exponent as the original U(1) field.
As a long awaited result, we show that monopoles are created and annihilated in
pairs as a function of real time in excess to a fixed average monopole number.Comment: Contribution to the "International Conference on Color Confinement
and Hadrons in Quantum Chromodynamics - Confinement 2003" (Tokyo, Japan,
2003-07-21 -- 2003-07-24); 5 pages; 6 figure
European Eastern Enlargement as Europe's Attempted Economic Suicide?
We argue that the process of European economic integration has made a qualitative shift: from a Listian symmetrical economic integration to an integrative and asymmetrical integration. This shift started in the early 1990s with the integration of the former Soviet economies into the economies of Europe and the world as a whole, reached its climax with the Eastern enlargement of the Union in 2004, and now forms the foundation of the renewed Lisbon Strategy. This change is measurably threatening European welfare: the economic periphery in the first instance, and potentially the core countries as well. Two parallel processes aggravate this development: the timing of the enlargement at this particular phase of the evolving techno-economic paradigm; and the creation of the European Monetary Union along the so-called Maastricht route towards convergence and fiscal stability.
Modernizing Russia: Round III. Russia and the other BRIC countries: forging ahead, catching up or falling behind?
The term 'BRIC countries' - Brazil, Russia, India, and China - traces its roots to investment banking, Goldman Sachs coined the term in 2001. The idea of large emerging economies catching up with, and challenging, the West has captured social scientists and policy-makers alike. However, the sheer size and different historical legacies dictate that there are enormous differences between the BRIC economies. RussiaĂżs situation is in three ways unique among the BRIC countries. First, Russia was an industrialized nation long before the others, secondly, it experienced unprecedented economic decline in the 1990s and by 2008 Russia barely reached the GDP level of 1989; thirdly, unlike Brazil, China, India and in fact most of the developing world, Russia is not a member of the World Trade Organization (WTO). These unique features beg the following questions that this document seeks to (at least tentatively) answer: first, what is the structural legacy of the decline in the 1990s in terms of technological and industrial capabilities in Russia; and second, what can and should Russia learn from the WTO experience of the rest of the BRIC economies until today. We argue, in brief, that while the decline of the 1990s is relatively well-known and documented on the macro-level (GDP) and more controversially in some of its micro-level and sociological impacts, there seems to be little awareness of the magnitude of devastation that took place during this period within RussiaĂżs industry. Along with a massive increase in income from natural resources, a partial disintegration of the R&D system, and a greatly diminished policy capacity, the structural changes of the 1990s continue to pose grave challenges to RussiaĂżs economic policy making. In fact, in many areas RussiaĂżs technological and industrial capabilities have simply been lost.
Thermodynamics of (2+1)-flavor strongly interacting matter at nonzero isospin
We investigate the phase structure of strongly interacting matter at
non-vanishing isospin before the onset of pion condensation in the framework of
the unquenched Polyakov-Quark-Meson model with 2+1 quark flavors. We show
results for the order parameters and all relevant thermodynamic quantities. In
particular, we obtain a moderate change of the pressure with isospin at
vanishing baryon chemical potential, whereas the chiral condensate decreases
more appreciably. We compare the effective model to recent lattice data for the
decrease of the pseudo-critical temperature with the isospin chemical
potential. We also demonstrate the major role played by the value of the pion
mass in the curvature of the transition line, and the need for lattice results
with a physical pion mass. Limitations of the model at nonzero chemical
potential are also discussed.Comment: 8 pages, 4 figures; version published in Phys. Lett.
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