Self domestication and the evolution of language

We set out an account of how self-domestication plays a crucial role in the evolution of language. In doing so, we focus on the growing body of work that treats language structure as emerging from the process ofcultural transmission. We argue that a full recognition of the importance of cultural transmission fundamentally changes the kind ofquestionswe should be asking regarding the biological basis of language structure. If we think of language structure as reflecting an accumulated set of changes in our genome, then we might ask something like, "What are the genetic bases of language structure and why were they selected?" However, if cultural evolution can account for language structure, then this question no longer applies. Instead, we face the task of accounting for the origin of the traits that enabled that process of structure-creating cultural evolution to get started in the first place. In light of work on cultural evolution, then, the new question for biological evolution becomes, "How did those precursor traits evolve?" We identify two key precursor traits: (1) the transmission of the communication system throughlearning; and (2) the ability to infer thecommunicative intentassociated with a signal or action. We then describe two comparative case studies-the Bengalese finch and the domestic dog-in which parallel traits can be seen emerging followingdomestication. Finally, we turn to the role of domestication in human evolution. We argue that the cultural evolution of language structure has its origin in an earlier process of self-domestication.</p

Heterogeneous consumption in OLG model with horizontal innovations

The paper develops a general equilibrium endogenous growth model involving heterogeneous consumption by an age-structured population with uncertain but limited life span and balanced life-time budget without bequests. The heterogeneity is introduced via weights which the individuals attribute in their utility function to consumption of different goods depending on the vintage of the good. The goods are produced by monopolistically competitive firms and the variety of available goods/technologies is determined endogenously through R&D investments. A competitive bank sector provides financial resources for investments, secured by agents’ savings and future firms profits. The general equilibrium is characterized by a system of functional equations and is analytically or numerically determined for several particular weight functions. It is shown that the investments by agents alone may be insufficient to sustain growth, while additional investments provided by the bank sector may lead to growth. The resulting imbalance between agents’ assets and the total value of firms can grow unboundedly in the case of homogeneous consumption. The results exhibit the qualitative difference between the dynamics of the model with heterogeneous versus homogeneous consumption. In particular heterogeneous con- sumption (when old goods are discounted) reduces the additional investments by the financial sector so that the values of firms become balanced by the assets of agents in the long run.info:eu-repo/semantics/publishedVersio

The Jacob2 Lectin of the Entamoeba histolytica Cyst Wall Binds Chitin and Is Polymorphic

For many years, we and others have used cysts of Entamoeba invadens (Ei), a reptilian parasite, to model the infectious and diagnostic cysts of the human pathogen Entamoeba histolytica (Eh). The Ei cyst wall is composed of chitin fibrils, as well as Jacob and Jessie lectins that have unique chitin-binding domains. Our recent results suggest a “wattle and daub” model of the Ei cyst wall, where the wattle or sticks (chitin fibrils bound by multivalent Jacob lectins) is constructed prior to the addition of the mortar or daub (self-aggregating Jessie3 lectins). Here we “humanize” the Ei model of the cyst wall with four findings. First, a recombinant Eh Jacob2 lectin, which has three predicted chitin-binding domains surrounding a large spacer domain, binds chitin beads. Second, polymorphisms in the spacer domain of EhJacob2 discriminate clinical isolates of Entamoeba. Third, chitinase, Jacob2 lectin, and Jessie3 lectin are present in cyst walls of clinical isolates of Entamoeba. Finally, numerous sera from patients infected with Entamoeba recognize recombinant Eh Jacob1 and Jessie3 lectins

Evidence for a “Wattle and Daub” Model of the Cyst Wall of Entamoeba

The cyst wall of Entamoeba invadens (Ei), a model for the human pathogen Entamoeba histolytica, is composed of fibrils of chitin and three chitin-binding lectins called Jacob, Jessie3, and chitinase. Here we show chitin, which was detected with wheat germ agglutinin, is made in secretory vesicles prior to its deposition on the surface of encysting Ei. Jacob lectins, which have tandemly arrayed chitin-binding domains (CBDs), and chitinase, which has an N-terminal CBD, were each made early during encystation. These results are consistent with their hypothesized roles in cross-linking chitin fibrils (Jacob lectins) and remodeling the cyst wall (chitinase). Jessie3 lectins likely form the mortar or daub of the cyst wall, because 1) Jessie lectins were made late during encystation; 2) the addition to Jessie lectins to the cyst wall correlated with a marked decrease in the permeability of cysts to nucleic acid stains (DAPI) and actin-binding heptapeptide (phalloidin); and 3) recombinant Jessie lectins, expressed as a maltose-binding proteins in the periplasm of Escherichia coli, caused transformed bacteria to agglutinate in suspension and form a hard pellet that did not dissociate after centrifugation. Jessie3 appeared as linear forms and rosettes by negative staining of secreted recombinant proteins. These findings provide evidence for a “wattle and daub” model of the Entamoeba cyst wall, where the wattle or sticks (chitin fibrils likely cross-linked by Jacob lectins) is constructed prior to the addition of the mortar or daub (Jessie3 lectins)

A polymorphic variant of the insulin-like growth factor 1 (IGF-1) receptor correlates with male longevity in the Italian population: a genetic study and evaluation of circulating IGF-1 from the "Treviso Longeva (TRELONG)" study

<p>Abstract</p> <p>Background</p> <p>An attenuation of the insulin-like growth factor 1 (IGF-1) signaling has been associated with elongation of the lifespan in simple metazoan organisms and in rodents. In humans, IGF-1 level has an age-related modulation with a lower concentration in the elderly, depending on hormonal and genetic factors affecting the IGF-1 receptor gene (<it>IGF-1R</it>).</p> <p>Methods</p> <p>In an elderly population from North-eastern Italy (<it>n </it>= 668 subjects, age range 70–106 years) we investigated the <it>IGF-1R </it>polymorphism G3174A (<it>rs2229765</it>) and the plasma concentration of free IGF-1. Frequency distributions were compared using χ²-test "Goodness of Fit" test, and means were compared by one-way analysis of variance (ANOVA); multiple regression analysis was performed using JMP7 for SAS software (SAS Institute, USA). The limit of significance for genetic and biochemical comparison was set at α = 0.05.</p> <p>Results</p> <p>Males showed an age-related increase in the A-allele of <it>rs2229765 </it>and a change in the plasma level of IGF-1, which dropped significantly after 85 years of age (85+ group). In the male 85+ group, A/A homozygous subjects had the lowest plasma IGF-1 level. We found no clear correlation between <it>rs2229765 </it>genotype and IGF-1 in the females.</p> <p>Conclusion</p> <p>These findings confirm the importance of the <it>rs2229765 </it>minor allele as a genetic predisposing factor for longevity in Italy where a sex-specific pattern for IGF-1 attenuation with ageing was found.</p

Market Imitation and Win-Stay Lose-Shift Strategies Emerge as Unintended Patterns in Market Direction Guesses.

Decisions made in our everyday lives are based on a wide variety of information so it is generally very difficult to assess what are the strategies that guide us. Stock market provides a rich environment to study how people make decisions since responding to market uncertainty needs a constant update of these strategies. For this purpose, we run a lab-in-the-field experiment where volunteers are given a controlled set of financial information -based on real data from worldwide financial indices- and they are required to guess whether the market price would go "up" or "down" in each situation. From the data collected we explore basic statistical traits, behavioural biases and emerging strategies. In particular, we detect unintended patterns of behavior through consistent actions, which can be interpreted as Market Imitation and Win-Stay Lose-Shift emerging strategies, with Market Imitation being the most dominant. We also observe that these strategies are affected by external factors: the expert advice, the lack of information or an information overload reinforce the use of these intuitive strategies, while the probability to follow them significantly decreases when subjects spends more time to make a decision. The cohort analysis shows that women and children are more prone to use such strategies although their performance is not undermined. Our results are of interest for better handling clients expectations of trading companies, to avoid behavioural anomalies in financial analysts decisions and to improve not only the design of markets but also the trading digital interfaces where information is set down. Strategies and behavioural biases observed can also be translated into new agent based modelling or stochastic price dynamics to better understand financial bubbles or the effects of asymmetric risk perception to price drops

Identification and Characterization of a Mef2 Transcriptional Activator in Schistosome Parasites

Myocyte enhancer factor 2 protein (Mef2) is an evolutionarily conserved activator of transcription that is critical to induce and control complex processes in myogenesis and neurogenesis in vertebrates and insects, and osteogenesis in vertebrates. In Drosophila, Mef2 null mutants are unable to produce differentiated muscle cells, and in vertebrates, Mef2 mutants are embryonic lethal. Schistosome worms are responsible for over 200 million cases of schistosomiasis globally, but little is known about early development of schistosome parasites after infecting a vertebrate host. Understanding basic schistosome development could be crucial to delineating potential drug targets. Here, we identify and characterize Mef2 from the schistosome worm Schistosoma mansoni (SmMef2). We initially identified SmMef2 as a homolog to the yeast Mef2 homolog, Resistance to Lethality of MKK1P386 overexpression (Rlm1), and we show that SmMef2 is homologous to conserved Mef2 family proteins. Using a genetics approach, we demonstrate that SmMef2 is a transactivator that can induce transcription of four separate heterologous reporter genes by yeast one-hybrid analysis. We also show that Mef2 is expressed during several stages of schistosome development by quantitative PCR and that it can bind to conserved Mef2 DNA consensus binding sequences

Effects of thermal water inhalation in chronic upper respiratory tract infections in elderly and young patients

Background: Chronic upper respiratory tract infections (cURTI) are very frequent illnesses which occur at any age of life. In elderly, cURTI are complicated by immunosenescence, with involvement of lung immune responsiveness. Results: In the present study, 51 elderly (age range: 66-86) and 51 young (age range 24-58) cURTI patients underwent a single cycle (two weeks) of inhalatory therapy with salt-bromide-iodine thermal water in the thermal station "Margherita di Savoia" (Margherita di Savoia, BAT, Italy). Peripheral blood serum cytokines and clinical assessment were performed before therapy (T0) and after six months (T1) and 12 months (T2) from inhalatory treatment. In both elderly and young patients, at baseline an increased release of T helper (h)1-related cytokines [interleukin (IL)-2 and interferon-γ] and of Th2-related cytokine (IL-4) was documented. Inhalatory treatment reduced the excessive secretion of all the above-cited cytokines. IL-10 values were above normality at all times considered in both groups of patients. In addition, an increase in IL-17 and IL-21 serum levels following therapy was observed in both groups of patients. Pro-inflammatory cytokine (IL-1β, IL-6, IL-8 and tumor necrosis factor-α) baseline values were lower than normal values at T0 in both elderly and young cURTI patients. Their levels increased following inhalatory treatment. Clinically, at T2 a dramatic reduction of frequency of upper respiratory tract infections was recorded in both groups of patients. Conclusion: Thermal water inhalation is able to modulate systemic immune response in elderly and young cURTI patients, thus reducing excessive production of Th1 and Th2-related cytokines, on the one hand. On the other hand, increased levels of IL-21 (an inducer of Th17 cells) and of IL-17 may be interpreted as a protective mechanism, which likely leads to neutrophil recruitment in cURTI patients. Also restoration of pro-inflammatory cytokine release following inhalatory therapy may result in microbe eradication. Quite importantly, the maintenance of high levels of IL-10 during the follow-up would suggest a consistent regulatory role of this cytokine in attenuating the pro-inflammatory arm of the immune response

Problems with Using the Normal Distribution – and Ways to Improve Quality and Efficiency of Data Analysis

Background: The Gaussian or normal distribution is the most established model to characterize quantitative variation of original data. Accordingly, data are summarized using the arithmetic mean and the standard deviation, by x 6 SD, or with the standard error of the mean, x 6 SEM. This, together with corresponding bars in graphical displays has become the standard to characterize variation. Methodology/Principal Findings: Here we question the adequacy of this characterization, and of the model. The published literature provides numerous examples for which such descriptions appear inappropriate because, based on the ‘‘95 % range check’’, their distributions are obviously skewed. In these cases, the symmetric characterization is a poor description and may trigger wrong conclusions. To solve the problem, it is enlightening to regard causes of variation. Multiplicative causes are by far more important than additive ones, in general, and benefit from a multiplicative (or log-) normal approach. Fortunately, quite similar to the normal, the log-normal distribution can now be handled easily and characterized at the level of the original data with the help of both, a new sign, x /, times-divide, and notation. Analogous to x 6 SD, it connects the multiplicative (or geometric) mean x * and the multiplicative standard deviation s * in the form x * x /s*, that is advantageous and recommended. Conclusions/Significance: The corresponding shift from the symmetric to the asymmetric view will substantially increas

Phosphorylcholine Allows for Evasion of Bactericidal Antibody by Haemophilus influenzae

The human pathogen Haemophilus influenzae has the ability to quickly adapt to different host environments through phase variation of multiple structures on its lipooligosaccharide (LPS), including phosphorylcholine (ChoP). During colonization with H. influenzae, there is a selection for ChoP+ phase variants. In a murine model of nasopharyngeal colonization, this selection is lost in the absence of adaptive immunity. Based on previous data highlighting the importance of natural antibody in limiting H. influenzae colonization, the effect of ChoP expression on antibody binding and its bactericidal activity was investigated. Flow cytometric analysis revealed that ChoP+ phase variants had decreased binding of antibody to LPS epitopes compared to ChoP− phase variants. This difference in antibody binding correlated with increased survival of ChoP+ phase variants in the presence of antibody-dependent, complement-mediated killing. ChoP+ phase variants were also more resistant to trypsin digestion, suggesting a general effect on the physical properties of the outer membrane. Moreover, ChoP-mediated protection against antibody binding correlated with increased resilience of outer membrane integrity. Collectively, these data suggest that ChoP expression provides a selective advantage during colonization through ChoP-mediated effects on the accessibility of bactericidal antibody to the cell surface