23,602 research outputs found
Definition of the Subfamily Hedobiinae Based on Larval Characteristics (Coleoptera: Anobiidae)
Recently, Espanol (1968, 1970) redefined the subfamily Hedobiinae and, using the anatomy of adults, presented a key to separate the eight genera which form it. He also introduced some notable modifications, among them the inclusion of Ptilineurus and Clada in the subfamily and the elevation of Ptinomorphus Mulsant and Rey to generic rank. The latter genus includes, among others, the species P. imperialis Linnaeus and regalis Duftschmid, from Europe and P. granosus LeConte and angularus Fall from the United States of America
Adaptation to criticality through organizational invariance in embodied agents
Many biological and cognitive systems do not operate deep within one or other
regime of activity. Instead, they are poised at critical points located at
phase transitions in their parameter space. The pervasiveness of criticality
suggests that there may be general principles inducing this behaviour, yet
there is no well-founded theory for understanding how criticality is generated
at a wide span of levels and contexts. In order to explore how criticality
might emerge from general adaptive mechanisms, we propose a simple learning
rule that maintains an internal organizational structure from a specific family
of systems at criticality. We implement the mechanism in artificial embodied
agents controlled by a neural network maintaining a correlation structure
randomly sampled from an Ising model at critical temperature. Agents are
evaluated in two classical reinforcement learning scenarios: the Mountain Car
and the Acrobot double pendulum. In both cases the neural controller appears to
reach a point of criticality, which coincides with a transition point between
two regimes of the agent's behaviour. These results suggest that adaptation to
criticality could be used as a general adaptive mechanism in some
circumstances, providing an alternative explanation for the pervasive presence
of criticality in biological and cognitive systems.Comment: arXiv admin note: substantial text overlap with arXiv:1704.0525
Masses of the Goldstone modes in the CFL phase of QCD at finite density
We construct the U_L(3) x U_R(3) effective lagrangian which encodes the
dynamics of the low energy pseudoscalar excitations in the Color-Flavor-Locking
superconducting phase of QCD at finite quark density. We include the effects of
instanton-induced interactions and study the mass pattern of the pseudoscalar
mesons. A tentative comparison with the analytical estimate for the gap
suggests that some of these low energy momentum modes are not stable for
moderate values of the quark chemical potential.Comment: 15 pages, 5 figures; Discussion of quark mass effects at very large
densities amended, references adde
Dissipative processes in superfluid quark matter
We present some results about dissipative processes in fermionic superfluids
that are relevant for compact stars. At sufficiently low temperatures the
transport properties of a superfluid are dominated by phonons. We report the
values of the bulk viscosity, shear viscosity and thermal conductivity of
phonons in quark matter at extremely high density and low temperature. Then, we
present a new dissipative mechanism that can operate in compact stars and that
is named "rocket term". The effect of this dissipative mechanism on superfluid
r-mode oscillations is sketched.Comment: 6 pages, 1 figure. Prepared for QCD@work 2010 - International
Workshop on QCD - Theory and Experiment, 20-23 June 2010, Martina Franca -
Valle d'Itria - Ital
Promoting Hope, Healing, and Wellness: Catholic Interventions in Behavioral Health Care
In this chapter, we will outline, highlight, and review some of the Catholic traditions and pastoral tools that can be integrated into any professional clinical practice in behavioral health care. We will focus our attention on six tools in particular that are particularly popular and unique within the Catholic faith tradition. We will also offer brief case illustrations to provide examples of how these Catholic tools can be effectively integrated into professional clinical practice
SURVIVAL OF THE SMALL FIRM AND THE ENTREPRENEUR UNDER DEMAND AND EFFICIENCY UNCERTAINTY
The objective of this paper is to offer an answer to the question : why do some entrepreneurs wish to own another firm in the future after having closed an unsuccessful one? We first show this question is relevant because making use of a sample of entrepreneurs in the UK who have experienced a business closure, we show that 45% of them have the desire to own another firm in the future, despite having an unsuccessful experience in small firm ownership. To tackle our question we develop a model where the profits of the small firm depend on two firm-specific parameters : the effciency parameter, which represents the skills of the entrepreneur to manage and cope efficiently with the everyday tasks of the small firm, and the demand parameter, which denotes the success of the firm’s product to attract demand or capture a market niche. It is found that our model answers our initial question by revealing the existence of a mechanism of entrepreneurial self-selection. Under such mechanism, skilful entrepreneurs are the only ones who wish to own another firm in the future, regardless of the degree of success in their previous venture, whereas unskilful entrepreneurs prefer to go to wage work. We show this mechanism accounts not only for the empirical evidence relevant to our initial question, but also for the rest of cases of entrepreneurs’ attitudes after experiencing a business closureSmall Firm ; Entrepreneur ; Survival ; Entrepreneurial Skills
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