What does it take to evolve behaviorally complex organisms?

What genotypic features explain the evolvability of organisms that have to accomplish many different tasks? The genotype of behaviorally complex organisms may be more likely to encode modular neural architectures because neural modules dedicated to distinct tasks avoid neural interference, i.e., the arrival of conflicting messages for changing the value of connection weights during learning. However, if the connection weights for the various modules are genetically inherited, this raises the problem of genetic linkage: favorable mutations may fall on one portion of the genotype encoding one neural module and unfavorable mutations on another portion encoding another module. We show that this can prevent the genotype from reaching an adaptive optimum. This effect is different from other linkage effects described in the literature and we argue that it represents a new class of genetic constraints. Using simulations we show that sexual reproduction can alleviate the problem of genetic linkage by recombining separate modules all of which incorporate either favorable or unfavorable mutations. We speculate that this effect may contribute to the taxonomic prevalence of sexual reproduction among higher organisms. In addition to sexual recombination, the problem of genetic linkage for behaviorally complex organisms may be mitigated by entrusting evolution with the task of finding appropriate modular architectures and learning with the task of finding the appropriate connection weights for these architectures

Objects, spatial compatibility, and affordances: A connectionist study

In two Artificial Life simulations we evolved artificial organisms possessing a visual and a motor system, and whose nervous system was simulated with a neural network. Each organism could see four objects, either upright or reversed, with a left or a right handle. In Task 1 they learned to reach the object handle independently of the handle\u27s position. In Task 2 they learned to reach one of two buttons located below the handle either to decide either where the handle was (Simulation 1) or whether the object was upright or reversed (Simulation 2). Task 1 simulated real life experience, Task 2 replicated either a classic spatial compatibility task (Simulation 1) or an experiment by Tucker & Ellis (1998) (Simulation 2). In both simulations learning occurred earlier in the Compatible condition, when the button to reach and the handle were on the same side, than in the Incompatible condition

Problem of the Integration of the Tools of Environmental Politics, VAS (Ex Directive 2001/42/CE), EMAS (Rule 761/2001/CE), and New Model of Industrial Sustainable Area

The study deepens the problem list in the application of the VAS and the new procedures relative EMAS II° to industrial areas e/o territorial organizations, and it analyzes some cases of study. The cases of study analyzed are those of the district of Solofra and the area ASI in Trapani in south Italy, and Prato in centre Italy, The objective principals of the project are integral part of the project LIFE-SIAM 2005: to define to analyze the degree of vertical integration (from the directive UEs to the local actions) and horizontal (from the partenariato for the governance to the forums of AG21L) of the principles of the sustainability and the governance in the territory beginning from the location and management of the industrial areas; the analysis of the methods experimented of shared territorial planning of the development, based on an approach multidisciplinary, comprendente partenariato, planning, evaluation and monitoring; the analysis of the levels of know managerial how and necessary planning development of a collaborative climate and of effective relationships among the Local Authorities, the citizens, the productive system, the experts and the scientific world; the analysis of the necessary professional dimensions and applications with the purpose to form new subject responsible and figures professional able to plan and to manage the governance and the sustainable development beginning from the industrial areas. The project as defined a new Model of Industrial Sustainable Area. These objectives of analysis will be pursued through the verification on the field of the state of application, the adaptation and the integration of different community tools of environmental politics, what the Evaluation Environmental Strategy (VAS), ex Directive 2001/42/CE and the EMAS, ex Rule 761/2001/CE, in the procedures of governance effected on the territory. The study intends to give a contribution to show the difficulties attuative in to integrate different voluntary community tools inside models as the governance, or of policy as the sustainable development, and to allow one innovative approach of theirs, how much more possible inserted in the planning and territorial management. The study as experimented the application of the Model in the case study.

A knowledge-based approach to the layout optimization of human–robot collaborative workplace

AbstractHuman–robot collaboration (HRC) solutions are replacing classic industrial robot due to the possibility of realizing more flexible production systems. Collaborative robot systems, named cobot, can work side by side with humans combining their strengths. However, obtaining an efficient HRC is not trivial; indeed, the potential advantages of the collaborative robotics increase as complexity increases. In this context, the main challenge is to design the layout of collaborative workplaces facing the facility layout problem and ensuring the safety of the human being. To move through the high number of safety standards could be very tiring and unproductive. Therefore, in this work a list of key elements, linked to reference norms and production needs, characterizing the collaborative workplace has been identified. Then, a graph-based approach has been used in order to organize and easily manage this information. The management by means graphs has facilitated the implementation of the acquired knowledge in a code, developed in Matlab environment. This code aims to help the designer in the layout organization of human–robot collaborative workplaces in standards compliance. The paper presents the optimization code, named Smart Positioner, and the operation is explained through a workflow diagram

N-acetyl-cysteine, a drug that enhances the endogenous activation of group-II metabotropic glutamate receptors, inhibits nociceptive transmission in humans.

Emerging research seeking novel analgesic drugs focuses on agents targeting group-II metabotropic glutamate receptors (mGlu2 and mGlu3 receptors). N-Acetylcysteine (NAC) enhances the endogenous activation of mGlu2/3 receptors by activating the glial glutamate:cystine membrane exchanger. Here, we examined whether NAC inhibits nociceptive responses in humans and animals. We tested the effect of oral NAC (1.2 g) on thermal-pain thresholds and laser-evoked potentials in 10 healthy volunteers, according to a crossover, double-blind, placebo-controlled design, and the effect of NAC (100 mg/kg, i.p.) on the tail-flick response evoked by radiant heat stimulation in mice.In healthy subjects, NAC treatment left thermal-pain thresholds unchanged, but significantly reduced pain ratings to laser stimuli and amplitudes of laser-evoked potentials. NAC induced significantly greater changes in these measures than placebo. In the tail-flick test, NAC strongly reduced the nocifensive reflex response to radiant heat. The action of NAC was abolished by the preferential mGlu2/3 receptor antagonist, LY341495 (1 mg/kg, i.p.).Our findings show for the first time that NAC inhibits nociceptive transmission in humans, and does the same in mice by activating mGlu2/3 receptors. These data lay the groundwork for investigating the therapeutic potential of NAC in patients with chronic pain

Study of the fracture behavior of a CuCrZr alloy

A previous study concerning the characterization of a CuCrZr alloy, considered as a possible candidate for the construction of passive satellites while highlighting some critical issues such as low hardness and elastic modulus, showed very interesting characteristics of toughness evaluated with preliminary tests on Charpy specimens and tensile tests. Considering that this alloy finds applications within the ITER project, an international program of great interest, it seems important to characterize many aspects of the alloy. For this reason, fatigue crack propagation rate (da/dn vs ΔK) and KIC measurements were performed, too