Communication in coral reef fish: the role of ultraviolet colour patterns in damselfish territorial behaviour

Many coral reef fish possess ultraviolet (UV) colour patterns. The behavioural significance of these patterns is poorly understood and experiments on this issue have not been reported for free-living reef fish in their natural environment. The damselfish Pomacentrus amboinensis has UV facial patterns, and spectroradiometric ocular media measurements show that it has the potential for UV vision. To test the potential behavioural significance of the UV patterns, I studied the response of males, in natural territories on the reef and in aquaria, to two conspecific intruders, one presented in a UV-transmitting (UV+) container and the other in a UV-absorbing (UV-) one. Territory owners attacked intruders viewed through UV+ filters significantly more often and for longer than intruders viewed through the UV- filter. In general, the results of the field experiment confirmed those of the laboratory experiment. The results support the hypothesis that P. amboinensis males are sensitive to UV light and that reflectance patterns, which appear in high contrast only in UV, modulate the level of aggressive behaviour. A recent survey showed that many predatory fish may not have UV vision and the use of UV colours in select species of reef fish may therefore serve as a 'private communication channel'. (C) 2004 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

Client fish ectoparasite loads and cleaner shrimp Urocaridella sp c hunger levels affect cleaning behaviour

Cleaning is a classic example of mutualism and determining the factors that maintain the balance between the costs and benefits for mutualist partners can assist our understanding of how cleaning relationships are maintained. Optimal foraging theory suggests two factors that might help to maintain the relationship between cleaners and their clients: client ectoparasite load and cleaner hunger levels. The ecological relevance and importance of foraging by cleaner fish in marine systems has been demonstrated repeatedly, yet there is little information available on this behaviour in cleaner shrimp. To determine whether cleaner shrimp base their choice of client fish on food patch quality (i.e. client fish ectoparasite load) we offered the yellow-beaked cleaner shrimp Urocaridella sp. c a choice of parasitized and unparasitized rock cods, Cephalopholis cyanostigma. To determine whether cleaner shrimp hunger levels influence cleaning time, we manipulated hunger levels in Urocaridella sp. c and examined their behaviour towards parasitized client fish. Cleaner shrimp preferred parasitized to unparasitized client fish and food-deprived cleaner shrimp cleaned parasitized rock cods more frequently than satiated cleaner shrimp did. Therefore, variations in client fish ectoparasite load and cleaner shrimp hunger level are two factors that affect the balance in this mutualism. Finally, our results meet some of the assumptions of biological market theory, a framework used to understand cooperative interactions, and thus this framework is suggested for future studies on this cleaning system.

Temperature influences the coercive mating and swimming performance of male eastern mosquitofish

Although the functional consequences of temperature variation have been examined for a wide range of whole-animal performance traits, the implications of thermal variation for reproductive behaviour or performance are poorly known. I examined the acute effects of temperature on the mating behaviour and swimming performance of male eastern mosquitofish, Gambusia holbrooki, which rely on a coercive strategy to obtain matings and are routinely exposed to wide daily temperature fluctuations. Males showed reproductive behaviours across the entire test temperature range of 14-38 degrees C, representing one of the widest reproductively active temperature ranges for any ectotherm. Both the time spent in pursuit of females and the total number of mating attempts increased with temperature to a plateau that started at approximately 22-26 degrees C. However, males maintained a constant level of copulations at 18-34 degrees C, the temperature range they routinely experience in southeast Queensland. In contrast, maximum swimming performance and approach speeds during copulations were highly thermally dependent across this temperature range. Thus, acute temperature variation has important fitness implications for male G. holbrooki, but mating performance was significantly limited only at extreme temperatures. (c) 2005 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

“Justice will be made“ Bush e o discurso construtor das guerras contra o terror

This work was built aiming to present how they built the speech of the presidential administration of George W. Bush to engender the Wars on Terror. Through an analysis of sources, magazines, newspapers and official speeches of the President; construct a survey that shows the process of development discourse of the U.S. government in order to make credible to the world the existence of weapons of mass destruction in Iraq. To accomplish this feat, the first attempts to deconstruct the work that would be the terrorist and their actions against the hegemonic governments, and perform an important discussion with the theme of the story of the present time and the need for a search like this nowadays. To deconstruct the idea of being a terrorist present as President George W. Bush uses the attacks of September 11th and fear as tools to build a war with a real intentionality toward the conquest of Iraqi oil and finish a task that his father, George H. Bush had left unfinished.

The Affordable Care Act and the Transformation of US Health Care

The neoliberal period was accompanied by a momentous transformation within the US health care system.  As the result of a number of political and historical dynamics, the healthcare law signed by President Barack Obama in 2010 ‑the Affordable Care Act (ACA)‑ drew less on universal models from abroad than it did on earlier conservative healthcare reform proposals. This was in part the result of the influence of powerful corporate healthcare interests. While the ACA expands healthcare coverage, it does so incompletely and unevenly, with persistent uninsurance and disparities in access based on insurance status. Additionally, the law accommodates an overall shift towards a consumerist model of care characterized by high cost sharing at time of use. Finally, the law encourages the further consolidation of the healthcare sector, for instance into units named “Accountable Care Organizations” that closely resemble the health maintenance organizations favored by managed care advocates. The overall effect has been to maintain a fragmented system that is neither equitable nor efficient. A single payer universal system would, in contrast, help transform healthcare into a social right.

Understandings of transnational families in debates on Migration and development

International migration sets in motion a range of significant transnational processes that connect countries and people. How migration interacts with development and how policies might promote and enhance such interactions have, since the turn of the millennium, gained attention on the international agenda. The recognition that transnational practices connect migrants and their families across sending and receiving societies forms part of this debate. The ways in which policy debate employs and understands transnational family ties nevertheless remain underexplored. This article sets out to discern the understandings of the family in two (often intermingled) debates concerned with transnational interactions: The largely state and policydriven discourse on the potential benefits of migration on economic development, and the largely academic transnational family literature focusing on issues of care and the micro-politics of gender and generation. Emphasizing the relation between diverse migration-development dynamics and specific family positions, we ask whether an analytical point of departure in respective transnational motherhood, fatherhood or childhood is linked to emphasizing certain outcomes. We conclude by sketching important strands of inclusions and exclusions of family matters in policy discourse and suggest ways to better integrate a transnational family perspective in global migration-development policy.

Marxism and Educational Theory

[pages, figure numbers, etc.], Oxford Research Encyclopedias: Education, edited by Noblit, G. W., [year of publication], reproduced by permission of Oxford University Press: http://education.oxfordre.com/

Investigation of the roles of CheD in the Bacillus subtilis chemotactic signal transduction

Abstract The two-component based chemotaxis signal transduction system allows flagellated bacteria to sense their surrounding chemical environment and move towards more favorable conditions. The attractant signals can be sensed by transmembrane chemoreceptors, and then transmitted to the histidine kinase CheA. Once activated, CheA interacts with the response regulator CheY through phosphorelay, which causes a change in the rotation of the flagella. The direction of flagella rotation determines whether a cell swims straight or just tumbles. Cells also need adaptation to respond to a change in chemical concentrations, and return to their prestimulated level. Adaptation in the B. subtilis chemotaxis system is achieved by three coordinated systems: the methylation system, the CheC/CheD/CheY-p system and the CheV system. CheD, the previously identified receptor deamidase, was shown to be critical to the ability of B. subtilis to perform chemotaxis and is the main focus of this study. This study started from characterization of the enzymatic mechanism of CheD. Results showed that CheD deamidase uses a cysteine hydrolase mechanism. The catalytic triad consisting of Cys33-His50-Thr27, and Ser27 is essential for receptor recognition and binding. In addition, in this study CheC was found to inhibit CheD’s deamidase activity. Through mutant screening, Phe102 on CheD was found to be the essential site to interact with CheC. Furthermore, the CheD/CheC interaction is necessary for the robust chemotaxis in vivo as demonstrated by the cheD (F102E) mutant, which lacks the ability to swim on swarm plates. Despite its deamidase activity, we hypothesized that CheD’s main role is its involvement in the CheD-CheC-CheY-p negative feedback pathway during adaptation. In particular, CheD is likely to help stabilize the transient kinase-activating state through binding to receptors. When CheY-p level is increased, CheC-CheY-p complex may attract CheD away from receptors. In this study, CheC-CheD binding kinetics with CheY or CheYp presence was successfully obtained by a series of SPR experiments. The increased affinity of CheD for CheC in presence of CheYp but not CheY makes likely the hypothesis that CheC-CheD-CheY interact as part of a negative feedback pathway during adaptation. Last, the interaction between CheD and chemoreceptor McpC was studied in order to better understand the role of CheD in adaptation. Results showed that Q304 and Q305 on McpC are essential to recruit CheD. Additionally, the reduced levels of CheD in mcpC (Q304A) or (Q305A) mutants suggested that the dynamic interaction between CheD and receptors is vital to maintain the normal CheD level. These findings suggest more complicated roles of CheD than its previously identified function as a receptor deamidase, and will lead to a clearer picture of the coordination of the three adaptational systems in the B. subtilis chemotactic sensory transduction system.

Peripheral communities of the Eastern Lau Spreading Center and Valu Fa Ridge: community composition, temporal change and comparison to near-vent communities

Western Pacific hydrothermal vents will soon be subjected to deep-sea mining and peripheral sites are considered the most practical targets. The limited information on community dynamics and temporal change in these communities makes it difficult to anticipate the impact of mining activities and recovery trajectories. We studied community composition of peripheral communities along a cline in hydrothermal chemistry on the Eastern Lau Spreading Center and Valu Fa Ridge (ELSC-VFR) and also studied patterns of temporal change. Peripheral communities located in the northern vent fields of the ELSC-VFR are significantly different from those in the southern vent fields. Higher abundances of zoanthids and anemones were found in northern peripheral sites and the symbiont-containing mussel Bathymodiolus brevior, brisingid seastars and polynoids were only present in the northern peripheral sites. By contrast, certain faunal groups were seen only in the southern peripheral sites, such as lollipop sponges, pycnogonids and ophiuroids. Taxonomic richness of the peripheral communities was similar to that of active vent communities, due to the presence of non-vent endemic species that balanced the absence of species found in areas of active venting. The communities present at waning active sites resemble those of peripheral sites, indicating that peripheral species can colonize previously active vent sites in addition to settling in the periphery of areas of venting. Growth and mortality were observed in a number of the normally slow-growing cladorhizid stick sponges, indicating that these animals may exhibit life history strategies in the vicinity of vents that differ from those previously recorded. A novel facultative association between polynoids and anemones is proposed based on their correlated distributions.

ENTREVISTA CON FRANZ HINKELAMMERT

El 05 de abril de 2001, en sesión ordinaria del Consejo Universitario de la Universidad Nacional, éste órgano de la UNA tomó el acuerdo de otorgar al Dr. Franz J. Hinkelammert, científico social alemán radicado en Costa Rica desde hace más de veinte años y uno de los fundadores del Departamento Ecuménico de Investigaciones(DEI); el Doctorado Honoris Causa, “por su excepcional aporte a las ciencias sociales contemporáneas”. El acto público para la entrega oficial de tal distinción se realizó un mes después, y en ese mismo acto, se le solicitó al Dr.Hinkelammert la entrega de una obra reciente o en preparación de su autoría, para que fuera publicada por la Editorial de la UNA, como parte del reconocimiento a su labor intelectual. El borrador final de esa obra fue entregada a la EUNA a finales de 2001, y tratándose de más de 500 páginas, tomó casi un año de prolijo trabajo la tarea de corrección y edición. Se trata del libro que comentamos en la presente entrevista, EL SUJETO Y LA LEY. El retorno del Sujeto reprimido, Editorial Universidad Nacional,Heredia, Costa Rica, 2003.

LA DOLARIZACIÓN PARCIAL EN COSTA RICA

Este estudio examina la magnitud, la evolución y explora las causas de la creciente preferencia hacia activos financieros en moneda extranjera como depósito de valor (sustitución de activos) y en algún grado como medio de pago (sustitución monetaria) en una economía de inflación moderada, sin antecedentes cercanos de crisis ni experiencias de confiscación de depósitos como es Costa Rica.La magnitud de la sustitución por parte del dólar estadounidense de las funciones que desempeña tradicionalmente la moneda local se aproxima a través de varios indicadores basados en razones de depósitos en moneda extranjera con respecto a sus similares en moneda local con frecuencia mensual de 1990 al 2002. Además, se identifican los factores que explican la demanda relativa de los depósitos bancarios según su grado de liquidez y se buscan evidencias de irreversibilidad del proceso (histéresis) mediante variables de tipo “ratchet”.Como factores explicativos del fenómeno, se plantean la probable influencia de elementos institucionales y de los estímulos económicos derivados de la globalización de la economía y de los diferenciales de rendimientos financieros. Pero se sostiene también que las políticas monetaria y cambiaria han tenido efectos en el nivel de dolarización alcanzado por la economía costarricense; por una parte, la política deencajes llevada a cabo desde 1996 favoreció la constitución de depósitos en moneda extranjera (y la intermediación de esos fondos ha debido generar la expansión secundaria de esos recursos) y, por otra, el ajuste cambiario siempre alcista bajo el régimen de minidevaluaciones ha estimulado la sustitución de activos.Se concluye en general que la dolarización de depósitos bancarios ha alcanzado niveles muy elevados (50% del total) y la significancia de la variable “ratchet” da indicios de que el proceso es de difícil reversión por lo que es de esperar que se mantenga en el futuro la preferencia de los agentes económicos nacionales por activos financieros en esa denominación tanto con propósitos de medio de cambio comode reserva de valor. Los factores que la teoría y la literatura apuntan como determinantes del fenómeno muestran ser relevantes en el caso costarricense: la demanda relativa por depósitos en dólares responde positivamente ante la tasa de interés y el ajuste cambiario esperado y negativamente ante el rendimiento diferencial a favor de los activos en moneda local. La apertura externa, aproximada por la evolución de las reservas monetarias internacionales, muestra ser significativa sólo para los depósitos que rinden utilidad como medio de pago y existen evidencias de la influencia positiva de las medidas de política económica señaladas sobre la dolarización de los depósitos bancarios.

HACIA UNA VISION SOCIOLOGIA DE LA ACCION ECONOMICA: DESARROLLOS Y DESAFIOS DE LA SOCIOLOGIA ECONOMICA

Este artículo analiza las principales contribuciones de una corriente emergente dentro del campo de la sociología denominada por quienes han promovido su desarrollo como sociología económica. Se sistematizan en el texto un conjunto de propuestas analíticas y formulaciones teóricas que en la bibliografía aparecen dispersas, pero cuya articulación enriquecería la comprensión que tenemos sobre el origen, configuración y dinámica de los mercados y de la acción económica de los sujetos sociales.El texto se estructura en torno a cuatro ideas básicas. Primero, que los mercados no son realidades universales y autocontenidas, sino, por el contrario, productos socio-históricos. Suconfiguración, estructura y dinámica están cruzadas por la presencia de instituciones sociales que hacen viable su surgimiento, consolidación y desarrollo. Segundo, que la acción económica no es llevada a cabo por agentes individuales dotados de una racionalidad económica que se superpone a cualquier otro tipo de racionalidad.

ANÁLISIS COMPARATIVO DE DOS FINCAS PRODUCTORAS DE CAFÉ ORGÁNICO UTILIZANDO LOS MÉTODOS DEL BALANCE ENERGÉTICO Y AGROECONÓMICO

En todos los procesos en que se transforma materia existe un flujo de energía, los sistemas productivos no se excluyen de esta regla, todo proceso productivo tiene una entrada (input) energía y una salida (output).La energía necesaria para la producción proviene de fuentes muy diversas, que podemos clasificar, de acuerdo con el tiempo que tarda el ciclo de formación de la materia prima, en: fuentes renovables a corto y mediano plazo, y fuentes renovables a largo plazo.Desde el descubrimiento del petróleo, la producción de energía se ha basado en fuentes renovables a muy largo plazo, de modo que el sistema no es sostenible. Las fuentes de combustibles fósiles se están agotando y los desechos producidos se acumulan porque su asimilación es más lenta que su formación.

EL ENFOQUE DE COMPETITIVIDAD SISTÉMICA COMO ESTRATEGIA PARA EL MEJORAMIENTO DEL ENTORNO EMPRESARIAL

Desde los años noventa se observa en Costa Rica al igual que en la región latinoamericana una menor polarización entre las principales escuelas económicas al analizar el tema del papel del Estado en la creación de condiciones para el desarrollo de la competitividad empresarial. A lo anterior ha contribuido el amplio debate que se viene dando en los últimos años sobre los procesos mas recientes de industrialización, caracterizados en algunos casos por la ausencia de logros positivos en materia de sostenibilidad y en otros por la existencia de resultados exitosos de las políticas adoptadas.Precisamente, en relación a la experiencia del Sudeste Asiático, Smith (2000: Xii) sostiene que "hay dificultades para explicar el éxito de la industrialización de estas economías en los términos de las teorías tradicionales y en consecuencia, se está poniendo mayor atención a nuevos enfoques de política industrial como el de seleccionar ganadores y el de los mercados gobernados".

O terrorismo transnacional e o planeamento estratégico de segurança nacional dos Estados Unidos da América

Estudos em homenagem ao VALM. António Emílio Ferraz Sacchetti