Private provision of public goods in the local interaction model

This paper analyses the evolutionary version of the Public Good game (Eshel, Samuelson, and Shaked (1998)) when agents can use imitation and best reply decision rules. I provide a condition, which completely describes agent behavior in the long run, for any number of neighbors and any total number of agents. Moreover, it is shown that it is enough to have just one decision rule per agent in order to obtain the same long run outcomes. The paper gives an explanation why we might observe irrational cooperation in the rational World

Bertrand competition with intertemporal demand

In the text-book model of dynamic Bertrand competition, competing firms meet the same demand function every period. This is not a satisfactory model of the demand side if consumers can make intertemporal substitution between periods. Each period then leaves some residual demand to future periods, and consumers who observe price under-cutting may correctly anticipate an ensuing price war and therefore postpone their purchases. Accordingly, the interaction between the firms no longer constitutes a repeated game, and hence falls outside the domain of the usual Folk theorems. We analyze collusive pricing in such situations, and study cases when consumers have perfect and imperfect foresight and varying degrees of patience. It turns out that collusion against patient and forward-looking consumers is easier to sustain than collusion in the text-book model

A generalized Tullock contest

We construct a generalized Tullock contest under complete information where contingent upon winning or losing, the payoff of a player is a linear function of prizes, own effort, and the effort of the rival. This structure nests a number of existing contests in the literature and can be used to analyze new types of contests. We characterize the unique symmetric equilibrium and show that small parameter modifications may lead to substantially different types of contests and hence different equilibrium effort levels

Purple corn extract induces long-lasting reprogramming and M2 phenotypic switch of adipose tissue macrophages in obese mice

Background: Obesity is a chronic and systemic infammatory disorder and an important risk factor for the onset of several chronic syndromes. Adipose tissue (AT) plays a crucial role in the development of obesity, promoting the infl\u2011 tration and accumulation of leukocytes in the tissue and sustaining adipocyte expansion. Anthocyanins exert a broad range of health benefts, but their efect in improving obesity-related infammation in vivo has been poorly character\u2011 ized. We examined the efects of a purple corn cob extract in the context of AT infammation in a murine diet-induced obesity (DIO) model. Methods: Male C57BL/6J mice were subjected to control diet (CTR+H2O), high fat diet (HF+H2O) or high fat diet plus purple corn extract (HF+RED) for 12 weeks. Blood glucose, AT, and liver gene expression, metabolism, biochem\u2011 istry, and histology were analysed and fow cytometry was performed on AT leukocytes and Kupfer cells. Results: RED extract intake resulted in lower MCP-1 mediated recruitment and proliferation of macrophages into crown-like structures in the AT. AT macrophages (ATM) of HF+RED group upregulated M2 markers (ArgI, Fizz1, TGF\u3b2), downregulating infammatory mediators (TNF-\u3b1, IL-6, IL-1\u3b2, COX-2) thanks to the suppression of NF-kB signalling. ATM also increased the expression of iron metabolism-related genes (FABP4, Hmox1, Ferroportin, CD163, TfR1, Ceruloplasmin, FtL1, FtH1) associated with a reduction in iron storage and increased turnover. ATM from HF+RED mice did not respond to LPS treatment ex vivo, confrming the long-lasting efects of the treatment on M2 polarization. Adipocytes of HF+RED group improved lipid metabolism and displayed a lower infammation grade. Liver histology revealed a remarkable reduction of steatosis in the HF+RED group, and Kupfer cell profling displayed a marked switch towards the M2 phenotype. Conclusions: RED extract attenuated AT infammation in vivo, with a long-lasting reprogramming of ATM and adipo\u2011 cyte profles towards the anti-infammatory phenotype, therefore representing a valuable supplement in the context of obesity-associated disorders

Strategically Equivalent Contests

Using a two-player Tullock-type contest, we show that intuitively and structurally different contests can be strategically equivalent. Strategically equivalent contests generate the same best response functions and, as a result, the same equilibrium efforts. However, strategically equivalent contests may yield different equilibrium payoffs. We propose a simple two-step procedure to identify strategically equivalent contests. Using this procedure, we identify contests that are strategically equivalent to the original Tullock contest, and provide new examples of strategically equivalent contests. Finally, we discuss possible contest design applications and avenues for future theoretical and empirical research

Influencia de la radiación UV-B, sobre la biosíntesis de antocianinas en frutos de manzana (Malus domestica Borkh) CV.”ANNA” para condiciones de trópico alto en Boyacá Colombia

1 recurso en línea (73 páginas) : figuras, tablas.En la manzana roja, la coloración de la piel y las características fisicoquímicas, son factores importantes que determinan la calidad de los frutos; estos parámetros tienen un control de orden genético pero influenciado por condiciones ambientales en etapa de maduración de frutos. El color rojo está ligado a la biosíntesis de antocianinas, que son un grupo de pigmentos de color rojo, hidrosolubles, producto del metabolismo secundario mediado por luz UV, Y ampliamente distribuidos en el reino vegetal. En el presente estudio se determinó el IUV, se cuantifico antocianinas totales y se analizaron SST en frutos maduros de manzana cv “ANNA” cultivados en diferentes altitudes en localidades de Boyacá: Soracá a 2820 m.s.n.m, Tuta a 2640m.s.n.m y Nuevo Colon a 2450 m.s.n.m. Los resultados mostraron que en la localidad a mayor altitud (Soracá), el valor promedio del IUV fue mayor (14.9) y la acumulación de antocianinas totales igualmente fue el más alto (25.4 mg/100g). Se ha encontrado una correlaciòn positiva entre la intensidad de la radiación UV, altitud y concentración de antocianinas totales, mientras que para los SST no se encontraron diferencias significativas.Bibliografía y webgrafía: páginas 61-70MaestríaMagíster en Ciencias Biológica

Plant–pathogen interactions and elevated CO2: morphological changes in favour of pathogens

Crop losses caused by pests and weeds have been estimated at 42% worldwide, with plant pathogens responsible for almost $10 billion worth of damage in the USA in 1994 alone. Elevated carbon dioxide [ECO2] and associated climate change have the potential to accelerate plant pathogen evolution, which may, in turn, affect virulence. Plant–pathogen interactions under increasing CO2 concentrations have the potential to disrupt both agricultural and natural systems severely, yet the lack of experimental data and the subsequent ability to predict future outcomes constitutes a fundamental knowledge gap. Furthermore, nothing is known about the mechanistic bases of increasing pathogen agressiveness. In the absence of information on crop species, it is shown here that plant pathogen (Erysiphe cichoracearum) aggressiveness is increased under ECO2, together with changes in the leaf epidermal characteristics of the model plant Arabidopsis thaliana L. Stomatal density, guard cell length, and trichome numbers on leaves developing post-infection are increased under ECO2 in direct contrast to non-infected responses. As many plant pathogens utilize epidermal features for successful infection, these responses provide a positive feedback mechanism facilitating an enhanced susceptibility of newly developed leaves to further pathogen attack. Furthermore, a screen of resistant and susceptible ecotypes suggest inherent differences in epidermal responses to ECO2

Overexpression of HvCslF6 in barley grain alters carbohydrate partitioning plus transfer tissue and endosperm development

In cereal grain sucrose is converted into storage carbohydrates; mainly starch, fructan and (1,3;1,4)-β-glucan (MLG). Previously, endosperm-specific overexpression of the HvCslF6 gene in hull-less barley resulted in high MLG and low starch content in mature grains. Morphological changes included inwardly elongated aleurone cells, irregular cell shapes of peripheral endosperm and smaller starch granules of starchy endosperm. Here we explored the physiological basis for these defects by investigating how changes in carbohydrate composition of developing grain impact mature grain morphology. Augmented MLG coincided with increased levels of soluble carbohydrates in the cavity and endosperm at the storage phase. Transcript levels of genes relating to cell wall, starch, sucrose and fructan metabolism were perturbed in all tissues. The cell walls of endosperm transfer cells (ETC) in transgenic grain were thinner and showed reduced mannan labelling relative to wild type. At the early storage phase rupture of the non-uniformly developed ETC and disorganization of adjacent endosperm cells was observed. Soluble sugars accumulated in the developing grain cavity, suggesting a disturbance of carbohydrate flow from the cavity towards the endosperm, resulting in a shrunken mature grain phenotype. Our findings demonstrate the importance of regulating carbohydrate partitioning in maintenance of grain cellularization and filling processes.Wai Li Lim, Helen M. Collins, Caitlin S. Byrt, Jelle Lahnstein, Neil J. Shirley, Matthew K. Aubert, Matthew R. Tucker, Manuela Peukert, Andrea Matros, and Rachel A. Burto