Widespread diversity deficits of coral reef sharks and rays.

A global survey of coral reefs reveals that overfishing is driving resident shark species toward extinction, causing diversity deficits in reef elasmobranch (shark and ray) assemblages. Our species-level analysis revealed global declines of 60 to 73% for five common resident reef shark species and that individual shark species were not detected at 34 to 47% of surveyed reefs. As reefs become more shark-depleted, rays begin to dominate assemblages. Shark-dominated assemblages persist in wealthy nations with strong governance and in highly protected areas, whereas poverty, weak governance, and a lack of shark management are associated with depauperate assemblages mainly composed of rays. Without action to address these diversity deficits, loss of ecological function and ecosystem services will increasingly affect human communities.

Conceptual frameworks and key questions for assessing the contribution of marine protected areas to shark and ray conservation.

Marine protected areas (MPAs) are key tools in addressing the global decline of sharks and rays, and marine parks and shark sanctuaries of various configurations have been established to conserve shark populations. However, assessments of their efficacy are compromised by inconsistent terminology, lack of standardized approaches to assess how MPAs contribute to shark and ray conservation, and ambiguity about how to integrate movement data in assessment processes. We devised a conceptual framework to standardize key terms (e.g., protection, contribution, potential impact, risk, threat) and used the concept of portfolio risk to identify key attributes of sharks and rays (assets), the threats they face (portfolio risk), and the specific role of MPAs in risk mitigation (insurance). Movement data can be integrated into the process by informing risk exposure and mitigation through MPAs. The framework is operationalized by posing 8 key questions that prompt practitioners to consider the assessment scope, MPA type and purpose, range of existing and potential threats, species biology and ecology, and management and operational contexts. Ultimately, MPA contributions to shark and ray conservation differ according to a complex set of human and natural factors and interactions that should be carefully considered in MPA design, implementation, and evaluation.

Marcos conceptuales y preguntas clave para evaluar la contribución de las áreas marinas protegidas a la conservación de tiburones y rayas Resumen Las áreas marinas protegidas (AMP) son herramientas importantes para manejar la declinación mundial de tiburones y rayas, por lo que se han establecido parques marinos y santuarios de diversas configuraciones para conservar las poblaciones de tiburones. Sin embargo, el análisis de su eficiencia está compuesto por una terminología inconstante, la falta de estrategias estandarizadas para evaluar cómo las AMP contribuyen a la conservación de tiburones y rayas, y una ambigüedad sobre cómo integrar la información sobre movimientos en los procesos de evaluación. Diseñamos un marco conceptual para estandarizar los términos más importantes (p. ej.: protección, contribución, impacto potencial, amenaza, riesgo) y usamos el concepto de riesgo de portafolio para identificar los atributos clave de los tiburones y las rayas (activos), las amenazas que enfrentan (riesgo de portafolio) y el papel específico que juegan las AMP en la mitigación del riesgo (seguro). La información sobre los movimientos puede integrarse al proceso al guiar la exposición y mitigación del riesgo con las AMP. El marco conceptual es operado con el planteamiento de ocho preguntas clave que invitan a los practicantes a considerar el enfoque de la evaluación, el tipo de AMP y su propósito, gama de amenazas existentes y potenciales, la biología y ecología de las especies, y los contextos operativos y de manejo. Finalmente, las contribuciones que tienen las AMP a la conservación de los tiburones y las rayas difieren de acuerdo con un conjunto complejo de factores naturales y humanos e interacciones que deberían considerarse cuidadosamente en el diseño, implementación y evaluación de la AMP.

Author Correction: Global status and conservation potential of reef sharks.

An Amendment to this paper has been published and can be accessed via a link at the top of the paper.

Global status and conservation potential of reef sharks.

Decades of overexploitation have devastated shark populations, leaving considerable doubt as to their ecological status1,2. Yet much of what is known about sharks has been inferred from catch records in industrial fisheries, whereas far less information is available about sharks that live in coastal habitats3. Here we address this knowledge gap using data from more than 15,000 standardized baited remote underwater video stations that were deployed on 371 reefs in 58 nations to estimate the conservation status of reef sharks globally. Our results reveal the profound impact that fishing has had on reef shark populations: we observed no sharks on almost 20% of the surveyed reefs. Reef sharks were almost completely absent from reefs in several nations, and shark depletion was strongly related to socio-economic conditions such as the size and proximity of the nearest market, poor governance and the density of the human population. However, opportunities for the conservation of reef sharks remain: shark sanctuaries, closed areas, catch limits and an absence of gillnets and longlines were associated with a substantially higher relative abundance of reef sharks. These results reveal several policy pathways for the restoration and management of reef shark populations, from direct top-down management of fishing to indirect improvement of governance conditions. Reef shark populations will only have a high chance of recovery by engaging key socio-economic aspects of tropical fisheries.

Benzothiophene containing Rho kinase inhibitors: Efficacy in an animal model of glaucoma.

We identified a new benzothiophene containing Rho kinase inhibitor scaffold in an ultra high-throughput enzymatic activity screen. SAR studies, driven by a novel label-free cellular impedance assay, were used to derive 39, which substantially reduced intraocular pressure in a monkey model of glaucoma-associated ocular hypertension.

Cyclic tetranuclear and hexanuclear palladium(II) complexes and their host-guest chemistry.

Cyclic tetrameric complexes have been prepared by the reaction of Pd(en)Cl2 or Pd(dapol)Cl2, or their nitrato analogues, with Na2(5'GMP) in aqueous solution, where en=1,2-diaminoethane, dapol=1,3-diamino-2-propanol, and 5'GMP=guanosine 5'-monophosphate. Addition of certain small molecules containing hydrophobic groups resulted in the expansion of the tetramer to a cyclic hexamer with strong bonding of one guest per hexameric host. At pH 5-6, the guest molecule can be a cation, anion, or neutral, and those species containing trimetylsilyl and t-butyl groups bonded the most strongly. The size of the central cavity of the [Pd(en)(5'GMP)]6 host has been estimated to be 5.2 A. Formation of the host-guest complex caused a large upfield shift (Deltadelta) of 2.5-2.9 ppm in the 1H NMR spectrum of the most highly affected guest protons, which were those in closest proximity to the guanine nucleobases. NOESY spectra were used to determine the interaction sites between the host and the guest. Apparent association constants determined at 26 degrees C and pD 5.4 for the [Pd(en)(5'GMP)]6-DSS and [Pd(en)(5'GMP)]6-t-butanol systems, where DSS is 3-(trimethylsilyl)-1-propanesulfonate anion, were 1.36+/-0.11x10(4) and 2.74+/-0.95x10(4) M(-3/2), respectively. The Pd(dapol)-5'GMP system forms hexameric host-guest complexes, similar in nature to those of the Pd(en)-5'GMP system. The molecular and crystal structures of Pd(dapol)Cl2 are also reported.