Choosing the greater of two goods: neural currencies for valuation and decision making

To make adaptive decisions, animals must evaluate the costs and benefits of available options. The nascent field of neuroeconomics has set itself the ambitious goal of understanding the brain mechanisms that are responsible for these evaluative processes. A series of recent neurophysiological studies in monkeys has begun to address this challenge using novel methods to manipulate and measure an animal's internal valuation of competing alternatives. By emphasizing the behavioural mechanisms and neural signals that mediate decision making under conditions of uncertainty, these studies might lay the foundation for an emerging neurobiology of choice behaviour.     

Crustacean Hyperglycemic Hormone (cHH) as a Modulator of Aggression in Crustacean Decapods

Biogenic amines, particularly serotonin, are recognised to play an important role in controlling the aggression of invertebrates, whereas the effect of neurohormones is still underexplored. The crustacean Hyperglycemic Hormone (cHH) is a multifunctional member of the eyestalk neuropeptide family. We expect that this neuropeptide influences aggression either directly, by controlling its expression, or indirectly, by mobilizing the energetic stores needed for the increased activity of an animal. Our study aims at testing such an influence and the possible reversion of hierarchies in the red swamp crayfish, Procambarus clarkii, as a model organism. Three types of pairs of similarly sized males were formed: (1) ‘control pairs’ (CP, n = 8): both individuals were injected with a phosphate saline solution (PBS); (2) ‘reinforced pairs’ (RP, n = 9): the alpha alone was injected with native cHH, and the beta with PBS; (3) ‘inverted pairs’ (IP, n = 9): the opposite of (2). We found that, independently of the crayfish’s prior social experience, cHH injections induced (i) the expression of dominance behaviour, (ii) higher glycemic levels, and (iii) lower time spent motionless. In CP and RP, fight intensity decreased with the establishment of dominance. On the contrary, in IP, betas became increasingly likely to initiate and escalate fights and, consequently, increased their dominance till a temporary reversal of the hierarchy. Our results demonstrate, for the first time, that, similarly to serotonin, cHH enhances individual aggression, up to reverse, although transitorily, the hierarchical rank. New research perspectives are thus opened in our intriguing effort of understanding the role of cHH in the modulation of agonistic behaviour in crustaceans.     

An experimental biomimetic platform for artificial olfaction

Artificial olfactory systems have been studied for the last two decades mainly from the point of view of the features of olfactory neuron receptor fields. Other fundamental olfaction properties have only been episodically considered in artificial systems. As a result, current artificial olfactory systems are mostly intended as instruments and are of poor benefit for biologists who may need tools to model and test olfactory models. Herewith, we show how a simple experimental approach can be used to account for several phenomena observed in olfaction. An artificial epithelium is formed as a disordered distributed layer of broadly selective color indicators dispersed in a transparent polymer layer. The whole epithelium is probed with colored light, imaged with a digital camera and the olfactory response upon exposure to an odor is the change of the multispectral image. The pixels are treated as olfactory receptor neurons, whose optical properties are used to build a convergence classifier into a number of mathematically defined artificial glomeruli. A non-homogenous exposure of the test structure to the odours gives rise to a time and spatial dependence of the response of the different glomeruli strikingly similar to patterns observed in the olfactory bulb. The model seems to mimic both the formation of glomeruli, the zonal nature of olfactory epithelium, and the spatio-temporal signal patterns at the glomeruli level. This platform is able to provide a readily available test vehicle for chemists developing optical indicators for chemical sensing purposes and for biologists to test models of olfactory system organization.     

Identification of an Interstitial 18p11.32-p11.31 Duplication Including the EMILIN2 Gene in a Family with Porokeratosis of Mibelli

Porokeratosis is a rare disease of epidermal keratinization characterized by the histopathological feature of the cornoid lamella, a column of tightly fitted parakeratocytic cells, whose etiology is still unclear. Porokeratosis of Mibelli is a subtype of porokeratosis presenting a single plaque or a small number of plaques of variable size located unilaterally on limbs. It frequently appears in childhood and occurs with a higher incidence in males. Cytogenetic analyses were performed in all members of the family on lesioned and uninvolved skin. An array-CGH analysis was also performed utilizing the Human Genome CGH Microarray Kit G3 400 with 5.3 KB overall median probe spacing. Gene expression was performed on skin fibroblasts. In this study, we describe a Caucasian healthy 4-year-old child and his father showing features of porokeratosis of Mibelli. Array-CGH analysis revealed an interstitial 429.5 Kb duplication of chromosome 18p11.32-p11.3 containing four genes, namely: SMCHD1, EMILIN2, LPIN2, and MYOM1 both in patient and his father. EMILIN2 resulted overexpressed on skin fibroblasts. Also other members of this family, without evident signs of porokeratosis, carried the same duplication. Among these genes, we focused our attention on elastin microfibril interfacer 2 (EMILIN2) gene. Apoptosis plays a fundamental role in maintaining epidermal homeostasis, balancing keratinocytes proliferation, and forming the stratum corneum. EMILIN2 is known to trigger the apoptosis of different cell lines negatively affecting cell survival. It is expressed in the skin. We could speculate that the duplication and overexpression of EMILIN2 cause an abnormal apoptosis of epidermal keratinocytes and alter the process of keratinization, even if other epigenetic and genetic factors could also be involved. Our results could contribute to a better understanding of the pathogenesis of porokeratosis of Mibelli.     

Experiential Key Species for Nature-disconnected Generations: An Expert-based Framework for Their A-priori Selection

In urbanized contexts, a progressive disconnection from nature, mainly experienced by the youngest generation, is evident. In this sense, detection of species more suitable for a nature-related experience becomes of primary importance to increase pro-environmental behaviors in children. Here, we propose a simple, quick, and explorative procedure for selecting a set of Experiential Key Species (EKS). Two practical examples are provided for two contexts (a urban park and a suburban wetland) where a large amount of data on vertebrate animal species are available. Depending on their density and eco-behavioral features, each species stimulates different experiences, here considered as a product of intensity and frequency of occurrence. Therefore, for each species we calculated an Experiential Magnitude score on a three-level scale with an expert-based method. We obtained 14 EKS in the urban park site (18% of total) and 18 EKS in the suburban wetland site (9.4%). We observed that in both sites EKS mainly include: (i) heterotherm species (mainly, fishes, amphibians, and water-related reptiles) and (ii) non-native species (about 36% in the urban park and about 17% in the suburban wetland). This information suggests that (i) following a conservation zoning approach, lakes, streams, and their shores may be considered the best experiential sites for children, and (ii) in conservation measures aimed to improve experience and pro-environmental behaviors in younger generations, the role of non-native species (that are of low or null conservation interest) might be relevant. In-deed, individuals of these species (i) are easily detectable, and (ii) may be collected, handled, and farmed with a limited (or absent) impact on biodiversity. In many anthropized contexts, these are the only species that can provide nature experience for younger generations. Based on our observations, we recommend practitioners (i) to adopt the procedure of EKS selection in critical contexts, also adding further regime attributes (area utilized, seasonal duration) to calculate the experiential magnitude score, and (ii) to test the effectiveness of this selection in conservation education projects.