Histological Study of the Sex-Change in the Skunk Clownfish Amphiprion akallopisos

Sex change in the protandrous fish Amphiprion akallopisos Bleeker, 1853 (F.Pomacentridae) has been analysed. Experiments consisted of placing males together after being separated from their mates, and observe changes in gonad histology at different periods, in order to identify signs of the sex change process. The presence of a first invagination on the male gonad wall, and the observation of the first cortical alveoli oocytes as an indication of the beginning of the vitellogenesis process, was the first symptom of the sex change, which has been detected after 18 days in one of the males. Period needed for the sex changing process was size independent. The process by which wall invagination is converted into ovarian lumen in the future mature ovary is also described

Modulation in Wistar rats of blood corticosterone compartmentation by sex and prior exposure to a cafeteria diet

In the metabolic syndrome, glucocorticoid activity is increased, but circulating levels show little change. Most of blood glucocorticoids are bound to corticosteroid-binding globulin (CBG), which liver expression and circulating levels are higher in females than in males. Since blood hormones are also bound to blood cells, and the size of this compartment is considerable for androgens and estrogens, we analyzed whether sex or eating a cafeteria diet altered the compartmentation of corticosterone in rat blood. The main corticosterone compartment in rat blood is that specifically bound to plasma proteins, with smaller compartments bound to blood cells or free. Cafeteria diet increased the expression of liver CBG gene, binding plasma capacity and the proportion of blood cell-bound corticosterone. There were marked sex differences in blood corticosterone compartmentation in rats, which were unrelated to testosterone. The use of a monoclonal antibody ELISA and a polyclonal Western blot for plasma CBG compared with both specific plasma binding of corticosterone and CBG gene expression suggested the existence of different forms of CBG, with varying affinities for corticosterone in males and females, since ELISA data showed higher plasma CBG for males, but binding and Western blot analyses (plus liver gene expression) and higher physiological effectiveness for females. Good cross- reactivity to the antigen for polyclonal CBG antibody suggests that in all cases we were measuring CBG.The different immunoreactivity and binding affinity may help explain the marked sex-related differences in plasma hormone binding as sex-linked different proportions of CBG forms.

Assessing the structural change of strategic mobility: determinants under hypercompetitive environments

The primary purpose of this exploratory empirical study is to examine the structural stability of a limited number of alternative explanatory factors of strategic change. On the basis of theoretical arguments and prior empirical evidence from two traditional perspectives, we propose an original empirical framework to analyse whether these potential explanatory factors have remained stable over time in a highly turbulent environment. This original question is explored in a particular setting: the population of Spanish private banks. The firms of this industry have experienced a high level of strategic mobility as a consequence of fundamental changes undergone in their environmental conditions over the last two decades (mainly changes related to the new banking and financial regulation process). Our results consistently support that the effect of most explanatory factors of strategic mobility considered did not remain stable over the whole period of analysis. From this point of view, the study sheds new light on major debates and dilemmas in the field of strategy regarding why firms change their competitive patterns over time and, hence, to what extent the "contextdependency" of alternative views of strategic change as their relative validation can vary over time for a given population. Methodologically, this research makes two major contributions to the study of potential determinants of strategic change. First, the definition and measurement of strategic change employing a new grouping method, the Model-based Cluster Method or MCLUST. Second, in order to asses the possible effect of determinants of strategic mobility we have controlled the non-observable heterogeneity using logistic regression models for panel data.

A change would do you good . . . An experimental study on how to overcome coordination failure in organizations

Many organizations suffer poor performance because individuals within the organization fail to coordinate on efficient patterns of behavior. Using controlled laboratory experiments, we study how financial incentives can be used to find a way out of such performance traps. Our experiments are set in a corporate environment where subjects' payoffs depend on coordinating at high effort levels; the underlying game being played repeatedly by employees is a weak-link game. In an initial phase, the benefits of coordination are low relative to the cost of increased effort. Play in this initial phase typically converges to an inefficient outcome with employees failing to coordinate at high effort levels. The experimental design then explores the effects of varying the financial incentives to coordinate at a higher effort level. We find that an increase in the benefits of coordination leads to improved coordination, but, surprisingly, large increases have no more impact than small increases. Once subj

Limitations and biases of conventional analysis of climate change. Towards an analysis coherent with sustainable development

This paper shows the numerous problems of conventional economic analysis in the evaluation of climate change mitigation policies. The article points out the many limitations, omissions, and the arbitrariness that have characterized most evaluation models applied up until now. These shortcomings, in an almost overwhelming way, have biased the result towards the recommendation of a lower aggressiveness of emission mitigation policies. Consequently, this paper questions whether these results provide an appropriate answer to the problem. Finally, various points that an analysis coherent with sustainable development should take into account are presented.

Globalization and Europeanization: Analysing Change

The main motivation for exploring the relationship between globalization and Europeanization is the understanding of the importance of exogenous factors for policy change at the domestic level. Can we distinguish the impact of Europeanization to that of globalization? What is the relationship between globalization and Europeanization and what can we learn about the impact of the two phenomena upon political institutions, public policies, identities and values of EU member-states? Can we distinguish the traces of globalization to those of Europeanization upon the domestic level? The paper draws upon International Relations and International Political Economy theories of globalization as well as upon the Europeanization literature. Both phenomena are multi-dimensional and in order to assess their impact and their relationship three dimensions are explored: political institutions, public policies and values and identities. It is concluded that the two phenomena are interwoven and that there is no antithetical relationship between them. Their core is similar, based on the values of neo-liberalism, representative democracy and open market economy.

Thickening of phase change materials (PCM) to avoid segregation

Estudi elaborat a partir d’una estada a Çukurova University, Turquia, al juliol del 2006. L’emmagatzematge d’energia tèrmica ha atret interès en aplicacions tèrmiques com l’aigua calenta, la calefacció i l’aire condicionat. Aquests sistemes són útils per corregir la no coincidència entre la oferta i la demanda d’energia. Principalment hi ha dos tipus de sistemes d’emmagatzematge d’energia tèrmica, emmagatzematge amb calor sensible i amb calor latent. L’emmagatzematge amb calor latent és particularment atractiu degut a la seva habilitat de donar una densitat d’emmagatzematge d’energia més alt i la seva característica d’emmagatzemar calor a una temperatura constant corresponent a la temperatura de transició de fase de la substància emmagatzemadora de calor. Les salts hidratades orgàniques tenen certes avantatges com a materials d’emmagatzematge de calor latent sobre els materials orgànics. En canvi, quan les salts hidratades s’utilitzen com a materials de canvi de fase (PCM) apareixen alguns problemes en les aplicacions d’emmagatzematge de calor latent. Aquests són el subrefredament de les salts hidratades quan es congelen degut a les seves dèbils propietats de nucleació, i la separació de fase que hi apareix degut a una fusió incongruent. En aquest estudi, s’estabilitza sal de Glauber (Na2SO4.10H2O) amb diferents concentracions de poliacrilamida i gelatina per prevenir la fusió incongruent. Per prevenir el subrefredament s’utilitza un agent nucleant amb una estructura cristal•lina semblant a la de la sal de Glauber. La capacitat d’emmagatzematge de calor de les mostres de PCM estabilitzades amb diferents concentracions de gels polimèrics es determinen amb DCS i amb el mètode T-history.

Desenvolupament de mesures per comparar transculturalment xarxes personals (USA i Estats Units)

Estudi elaborat a partir d’una estada a la Universitat de Florida durant Abril i Maig de 2006. “Application to Immigrant Populations in South Florida and Northeastern Spain" ha permès recollir les xarxes personals d’immigrants en els dos països mitjançant un qüestionari implementat amb un software desenvolupat ex professo per recollir i presentar visualment les dades. Es van revisar i assemblar les entrevistes i qüestionaris realitzats a Catalunya i a Estats Units (Miami i Nova York, especialment). Fins al moment s’han revisat i analitzat uns 450 casos. Un cop depurada i analitzada la informació obtinguda s’ha pogut disposar per primer cop de mesures globals pels diferents col•lectius estudiats. L'objectiu global del projecte és entendre les implicacions que les estructures de les xarxes personals tenen en relació a un conjunt de conductes (de salut, d'ús de la llengua, etx) i les autoconcepcions. En aquest sentit era necessari desenvolupar un seguit de mesures que permetessin comparar i documentar la variació de les estructures de les xarxes personals a diferents cultures, nivells socioeconòmics, gènere, religió, etc. i incorporar-les com a variables independents als models explicatius.En aquest moments s’està desenvolupant un índex basat en variables estructurals (número de components de la xarxa, densitat, grau d’intermediació, etc.) i variables de composició (proporció de persones diferents del país d’origen, entre d'altres). La idea és disposar d’un índex d’heterogeneïtat de la xarxa social comparable entre els diferents col•lectius. Malgrat que el treball continua, la principal conclusió a la que s’ha arribat és que al menys a Espanya a mida que passa el temps augmenta el nivell d’heterogeneïtat de les xarxes personals. És a dir, que desprès d’un ràpid procés de canvi i una fase de transnacionalitat la tendència és a reduir aquest nivell (pels costos socials i econòmics que comporta) depenent, naturalment, de factors com l’origen temporal (primera onada o successives), el tipus de col•lectiu i el sexe.

Equity and CO2 emissions distribution in climate change integrated assessment

Emissions distribution is a focus variable for the design of future international agreements to tackle global warming. This paper specifically analyses the future path of emissions distribution and its determinants in different scenarios. Whereas our analysis is driven by tools which are typically applied in the income distribution literature and which have recently been applied to the analysis of CO2 emissions distribution, a new methodological approach is that our study is driven by simulations run with a popular regionalised optimal growth climate change model over the 1995-2105 period. We find that the architecture of environmental policies, the implementation of flexible mechanisms and income concentration are key determinants of emissions distribution over time. In particular we find a robust positive relationship between measures of inequalities.

North-South trade and directed technical change

In a world where poor countries provide weak protection for intellectual property rights (IPRs), market integration shifts technical change in favor of rich nations. Through this channel, free trade may amplify international income differences. At the same time, integration with countries where IPRs are weakly protected can slow down the world growth rate. An important implication of these results is that protection of intellectual property is most beneficial in open countries. This prediction, which is novel in the literature, is consistent with evidence from a panel of 53 countries observed in the years 1965-1990. The paper also provides empirical support for the mechanism linking North-South trade to the direction of technical change: an increase in import penetration from low-wage, low-IPRs, countries is followed by a sharp fall in R&D investment in a panel of US manufacturing sectors.

Explaining Variation in Organizational Change: The Reform of Human Resource Management in the European Commission and the OECD

In this article we investigate the reforms of human resource management in the European Commission and the OECD by analyzing comparatively to what extent both organizations have adjusted their respective structures towards the ideal type of the so-called New Public Management (NPM). The empirical findings show that reforms towards NPM are more pronounced in the Commission than in the OECD. These findings are surprising for two reasons: First, it seems rather paradoxical that the OECD as central promoter of NPM at the international level lags behind the global trend when it comes to reforming its own structures. Second, this result is in contradiction with theoretical expectations, as they can be derived from theories of institutional isomorphism. To nevertheless account for the surprising results, it is necessary to modify and complement existing theories especially with regard to the scope conditions of their causal mechanisms.

Understanding sources of the change in international business cycles

Macroeconomic activity has become less volatile over the past three decades in most G7 economies. Current literature focuses on the characterization of the volatility reduction and explanations for this so called "moderation" in each G7 economy separately. In opposed to individual country analysis and individual variable analysis, this paper focuses on common characteristics of the reduction and common explanations for the moderation in G7 countries. In particular, we study three explanations: structural changes in the economy, changes in common international shocks and changes in domestic shocks. We study these explanations in a unified model structure. To this end, we propose a Bayesian factor structural vector autoregressive model. Using the proposed model, we investigate whether we can find common explanations for all G7 economies when information is pooled from multiple domestic and international sources. Our empirical analysis suggests that volatility reductions can largely be attributed to the decline in the magnitudes of the shocks in most G7 countries while only for the U.K., the U.S. and Italy they can partially be attributed to structural changes in the economy. Analyzing the components of the volatility, we also find that domestic shocks rather than common international shocks can account for a large part of the volatility reduction in most of the G7 countries. Finally, we find that after mid-1980s the structure of the economy changes substantially in five of the G7 countries: Germany, Italy, Japan, the U.K. and the U.S..