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

Preliminary evaluation of Septoria urticae Rob et Desm as a biological control agent of Urtica urens L

Plants of Urtica urens L (annual nettle) showing symptoms of severe foliar necrosis were collected in the horticultural belt of the city of La Plata (Province of Buenos Aires, Argentina). The agent causing the disease was identified as Septoria urticae Rob et Desm. Due to the severe lesions caused by the pathogen, its potential as a biocontrol agent of U urens was studied. Routine phytopathological techniques were used in order to evaluate the bioherbicide potential of the pathogen in the greenhouse on plants of U urens and other species of the Urticaceae family, such as Boehmeria nivea (L) Gaud, Pilea cadierei Gagn et Guil and Parietaria officinalis L. Using variance analysis it was shown that the pathogen caused a high percentage of defoliation and a reduction in dry weight (DW) of nettle plants, apart from significantly diminishing the seed production (number and DW) in the greenhouse. B nivea and P cadierei did not show any symptoms of the disease, whereas P officinalis was slightly affected by the fungus. This study suggests that the pathogen could play an important role as a biocontrol agent since it reduces U urens production.Évaluation préliminaire de Septoria urticae Rob et Desm comme agent de contrôle biologique de Urtica urens L. Des plantes de Urtica urens montrant des symptômes de nécrose foliaire sévère ont été ramassés dans la ceinture horticole de la ville de La Plata (Province de Buenos Aires, Argentina). L'agent qui cause la maladie a été identifié comme Septoria urticae Rob et Desm. À cause des lésions sévères provoquées par le pathogène, on a étudié son efficacité comme agent de lutte biologique contre U urens. Des techniques phytopathologiques de routine ont été employées pour évaluer le potentiel bioherbicide du pathogène en serre sur des plantes de U urens et d'autres espèces de la famille Urticaceae, telles que Boehmeria nivea (L) Gaud, Pilea cadierei Gagn et Guill et Parietaria officinalis L. L'analyse de variance a montré que le pathogène a causé un haut pourcentage de défoliation et une réduction du poids sec (DW) de plantes d'ortie, en plus d'une diminution significative de la production de semences en serre. B nivea et P cadierei n'ont pas montré de symptômes de la maladie, tandis que P officinalis a été légèrement affecté par le champignon. Cette étude suggère que le pathogène pourrait jouer un rôle important comme agent de biocontrôle, parce qu'il réduit la production de U urens

Impact of transient correction of increased adrenocortical activity in hypothalamo-damaged, hyperadipose female rats.

OBJECTIVE: To explore the effects of transient correction of enhanced corticoadrenal activity in monosodium L-glutamate (MSG)-damaged female rats on peripheral insulin sensitivity and in vitro retroperitoneal (RP) adipocyte function. DESIGNS: A dose of 4 mg/g body weight (BW) of MSG or vehicle (CTR) was i.p. injected, once every 2 days, between days 2 and 10 of age, in female rats. Intact and 21 day-operated (sham or adrenal enucleation (AE)) rats from both (CTR and MSG) groups were used for experimentation on day 120 of age. Circulating levels of several hormones, in basal and after i.v. high-glucose load conditions, and RP adiposity morphology and function were then evaluated. RESULTS: MSG rats developed increased adrenocortical function, hyperadiposity, hyperleptinemia, hyperinsulinemia and decreased peripheral insulin sensitivity. These characteristics were fully reversed after transient correction of corticoadrenal hyperactivity induced by AE. In addition, in vitro experimentation with isolated RP adipocytes indicated that cells from intact MSG animals displayed decreased sensitivity to insulin and dexamethasone stimulation of leptin secretion. Interestingly, adipocyte dysfunction in MSG rats was fully abrogated after AE-induced transient correction of insulinemia, leptinemia and adrenocortical activity. Importantly, the reversion of these metabolic abnormalities, induced by AE for 21 days, in MSG animals did occur, despite no significant changes in BW values. CONCLUSION: Our results support that the changes in adipocyte characteristics and peripheral insulin resistance, developed in this pseudo-obese female rat model, are mainly due to increased glucocorticoid production. Importantly, appropriate correction of the enhanced adrenocortical activity fully reversed these abnormal functions