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Critical Gaps (critical + gap)
Selected AbstractsEVOLUTION OF REPRODUCTIVE ISOLATION WITHIN A PARASITIC FUNGAL SPECIES COMPLEXEVOLUTION, Issue 7 2007Mickael Le Gac Despite important advances in the last few years, the evolution of reproductive isolation (RI) remains an unresolved and critical gap in our understanding of speciation processes. In this study, we investigated the evolution of RI among species of the parasitic fungal species complex Microbotryum violaceum, which is responsible for anther smut disease of the Caryophyllaceae. We found no evidence for significant positive assortative mating by M. violaceum even over substantial degrees of genetic divergence, suggesting a lack of prezygotic isolation. In contrast, postzygotic isolation increased with the genetic distance between mating partners when measured as hyphal growth. Total RI, measured as the ability of the pathogen to infect and produce a diploid progeny in the host plant, was significantly and positively correlated with genetic distance, remaining below complete isolation for most of the species pairs. The results of this study, the first one on the time course of speciation in a fungus, are therefore consistent with previous works showing that RI generally evolves gradually with genetic distance, and thus presumably with time. Interestingly, prezygotic RI due to gamete recognition did not increase with genetic distance, in contrast to the pattern found in plants and animals. [source] Directed attachment of antibodies to kinesin-powered molecular shuttlesBIOTECHNOLOGY & BIOENGINEERING, Issue 6 2009Amanda Carroll-Portillo Abstract Biomolecular motors, such as kinesin, have been used to shuttle a range of biological and synthetic cargo in microfluidic architectures. A critical gap in this technology is the ability to controllably link macromolecular cargo on microtubule (MT) shuttles without forming extraneous byproducts that may potentially limit their application. Here we present a generalized approach for functionalizing MTs with antibodies in which covalent bonds are formed between the carbohydrate in Fc region of polyclonal antibodies and the positively charged amino acids on the MT surface using the crosslinker succinimidyl 4-hydrazidoterephthalate hydrochloride (SHTH). Antibody-functionalized MTs (Ab-MTs) produced through this approach maintained motility characteristics and antigenic selectivity, and did not produce undesirable byproducts common to other approaches. We also demonstrate and characterize the application of these Ab-MTs for capturing and transporting bacterial and viral antigens. While this approach cannot be applied to monoclonal antibodies, which lack a carbohydrate moiety, it may be used for selectively functionalizing MT shuttles with a variety of carbohydrate-containing cargoes. Biotechnol. Bioeng. 2009; 104: 1182,1188. © 2009 Wiley Periodicals, Inc. [source] Climate change and the future for coral reef fishesFISH AND FISHERIES, Issue 3 2008Philip L Munday Abstract Climate change will impact coral-reef fishes through effects on individual performance, trophic linkages, recruitment dynamics, population connectivity and other ecosystem processes. The most immediate impacts will be a loss of diversity and changes to fish community composition as a result of coral bleaching. Coral-dependent fishes suffer the most rapid population declines as coral is lost; however, many other species will exhibit long-term declines due to loss of settlement habitat and erosion of habitat structural complexity. Increased ocean temperature will affect the physiological performance and behaviour of coral reef fishes, especially during their early life history. Small temperature increases might favour larval development, but this could be counteracted by negative effects on adult reproduction. Already variable recruitment will become even more unpredictable. This will make optimal harvest strategies for coral reef fisheries more difficult to determine and populations more susceptible to overfishing. A substantial number of species could exhibit range shifts, with implications for extinction risk of small-range species near the margins of reef development. There are critical gaps in our knowledge of how climate change will affect tropical marine fishes. Predictions are often based on temperate examples, which may be inappropriate for tropical species. Improved projections of how ocean currents and primary productivity will change are needed to better predict how reef fish population dynamics and connectivity patterns will change. Finally, the potential for adaptation to climate change needs more attention. Many coral reef fishes have geographical ranges spanning a wide temperature gradient and some have short generation times. These characteristics are conducive to acclimation or local adaptation to climate change and provide hope that the more resilient species will persist if immediate action is taken to stabilize Earth's climate. [source] WHO Atlas on Global Resources for Persons with Intellectual Disabilities 2007: Key Findings Relevant for Low- and Middle-Income CountriesJOURNAL OF POLICY AND PRACTICE IN INTELLECTUAL DISABILITIES, Issue 2 2008Céline Mercier Abstract, The World Health Organization (WHO) Atlas-ID project was designed to collect, compile, and disseminate information on intellectual disabilities (ID) services and resources from across the world. This paper aims at selecting findings in the Atlas-ID that can be used as a tool for advocacy, human rights awareness, development planning, and monitoring changes regarding resources for persons with intellectual disabilities and their families in countries with the lowest levels of income in the world. After consultation with experts in the field of ID, a questionnaire and its accompanying glossary were developed. This questionnaire was completed by national respondents from 147 countries, areas, and territories that are WHO members (response rate of 74.6% corresponding to 94.6% of the world population). Cross-tabulations were calculated according to WHO region that the countries belong to as well as their levels of income. The data from the Atlas-ID allowed for documenting similarities and differences among the poorest and the richest countries of the world in relation to ID. The most striking differences pertain to the areas of information, judicial protection, government benefits, financing, availability, and access to services. The Atlas-ID allowed the identification of similarities and differences in resources and services between the four World Bank categories of countries income, and it demonstrated the extent of unmet needs in low-income and low-middle-income countries, as well as some critical gaps between these countries and the high-level income countries. [source] Polymorphic microsatellite markers for paternity assessment in southern calamari Sepioteuthis australis (Cephalopoda: Loliginidae)MOLECULAR ECOLOGY RESOURCES, Issue 4 2003L. M. Van Camp Abstract Recent decades have seen the fast growth of cephalopod fisheries but their management is compromised by the critical gaps in our knowledge of cephalopod life histories. Molecular markers are invaluable tools for studying the evolutionary significance and management implications of variation in mating systems. We have developed seven polymorphic microsatellite loci for mating system analysis in the southern calamari Sepioteuthis australis Quoy & Gaimard 1833 using magnetic enrichment and colony hybridization techniques. Observed heterozygosities range from 32% to 100% and will have sufficient power to examine the relative success of alternate mating strategies in S. australis. [source] | ||||||||||