2,101 research outputs found
Western Immunoblotting in Avian Shell Gland Sample Immunoblotting Methods1
Avian shell gland tissue was subjected to Western blot analysis using anti-human estrogen receptor- α antibody H222. Initial attempts to obtain consistent, high-quality blots were unsuccessful because, as it turned out, excessive lipid in tissue preparations interfered with protein separation. Incremental additions of acetone eventually proved to be the critical step in solubilizing lipids and allowing consistent separation of bands on gels. A detailed description of the methodology is presented
Estrogen Receptor-α Populations Change with Age in Commercial Laying Hens
Older hens in production lay larger but fewer eggs than younger birds, and the incidence of soft and broken shells is greater in older hens than younger. These changes are attributable at least in part to changing hormone profiles and diminished ability of the hen to transport calcium at the duodenum. In further exploration of this relationship, a study was conducted with three ages of Hy-Line W-36 birds: prelay pullets (PL; 19 wk, 0% production), peak-production hens (PP; 29 wk, ∼93% production), and late-stage hens (LS; 71 wk, ∼80% production). Hens from the PP and LS groups were palpated for presence of an egg in the shell gland; hens were then euthanized and tissues (kidney, shell gland, hypothalamus) were removed for quantification of estrogen receptor- α (ERα) populations via immunocytochemical and Western blot analyses. Localization of ERα by immunostaining in the shell gland showed differences among age groups; however, no differences were noted in localization of ERα between age groups in the kidney and hypothalamus. In both the kidney and the shell gland there was a decrease in the amount of ERα, as detected by immunoblotting, in the LS hens compared to PL and PP birds (P \u3c 0.05). The results suggest that failure of calcium regulating mechanisms with age may be mediated at least in part through the reduced populations of estrogen receptors in certain critical tissues
Epidemiology and integrated control of Potato Late Blight in Europe
Phytophthora infestans, the causal agent of late blight, is a major threat to potato production in northwestern Europe. Before 1980, the worldwide population of P. infestans outside Mexico appeared to be asexual and to consist of a single clonal lineage of A1 mating type characterized by a single genotype. It is widely believed that new strains migrated into Europe in 1976 and that this led to subsequent population changes including the introduction of the A2 mating type. The population characteristics of recently collected isolates in NW Europe show a diverse population including both mating types, sexual reproduction and oospores, although differences are observed between regions. Although it is difficult to find direct evidence that new strains are more aggressive, there are several indications from experiments and field epidemics that the aggressiveness of P. infestans has increased in the past 20 years. The relative importance of the different primary inoculum sources and specific measures for reducing their role, such as covering dumps with plastic and preventing seed tubers from becoming infected, is described for the different regions. In NW Europe, varieties with greater resistance tend not to be grown on a large scale. From the grower’s perspective, the savings in fungicide input that can be achieved with these varieties are not compensated by the higher (perceived) risk of blight. Fungicides play a crucial role in the integrated control of late blight. The spray strategies in NW Europe and a table of the specific attributes of the most important fungicides in Europe are presented. The development and use of decision support systems (DSSs) in NW Europe are described. In The Netherlands, it is estimated that almost 40% of potato growers use recommendations based on commercially available DSS. In the Nordic countries, a new DSS concept with a fixed 7-day spray interval and a variable dose rate is being tested. In the UK, commercially available DSSs are used for c. 8% of the area. The validity of Smith Periods for the new population of P. infestans in the UK is currently being evaluated
Species of Eurydice (Isopoda, Flabellifera) from southern Brazil
This paper reports species of Eurydice (Isopoda, Flabellifera) occurring on the continental shelf of southern Brazil, from lat. 22º00'S. Three species are recorded. E. littoralis (Moore, 1902), is a new occurrence from Brazil. Detailed illustrations and new morphologi cal data are furnished for this species hitherto inadequately described. E. elongata sp. n. and E. emarginata sp. n., are new to science. The flagellar process on the antenna 2, reported in three species of Eurydice, seems to be an exclusively male characteristic, and probably it will also occur in the males of most of the already described species. Genus and species diagnosis are provided, together with a classification key for all species recorded up to date from southern Brazil. All available distributional and ecological infor mation completes the account of each species.No presente trabalho faz-se um levantamento das especies do gênero Eurydice (Isopoda, Flabellifera) ocorrendo na plataforma continental centrosul do Brasil, a partir da Lat. 22º00'S. Tres espécies são assinaladas para a região: E. littoralis (Moore, 1902), E. elongata sp. n. e E. emarginata sp.n. Novos dados morfológicos e detalhadas ilustrações são apresentadas para a espécie E. littoralis. O processo flagelar da antena 2, observado em três espécies de Eurydice, parece constituir uma característica exclusiva dos machos, donde se pressupõe possa também ser encontrado em outros machos de espécies já descritas. São fornecidas diagnoses para o gênero e espécie, assim como urna chave de classificação para todas as espécies tratadas. Tanto quanto possível, observações ecológicas completam a descrição das espécies
Global governance approaches to addressing illegal logging: Uptake and lessons learned
One of the most challenging tasks facing development agencies, trade ministries, environmental groups, social activists and forest-focused business interests seeking to ameliorate illegal logging and related timber trade is to identify and nurture promising global governance interventions capable of helping improve compliance to governmental policies and laws at national, subnational and local levels. This question is especially acute for developing countries constrained by capacity challenges and “weak states” (Risse, 2011). This chapter seeks to shed light on this task by asking four related questions: How do we understand the emergence of illegal logging as a matter of global interest? What are the types of global interventions designed to improve domestic legal compliance? How have individual states responded to these global efforts? What are the prospects for future impacts and evolution?
We proceed in the following steps. Following this introduction, step two reviews how the problem of “illegal logging” emerged on the international agenda. Step three reviews leading policy interventions that resulted from this policy framing. Step four reviews developments in selected countries/regions around the world according to their place on the global forest products supply chain: consumers (United States, Europe and Australia); middle of supply chain manufacturers (China and South Korea) and producers (Russia; Indonesia; Brazil and Peru; Ghana, Cameroon and the Republic of Congo). We conclude by reflecting on key trends that emerge from this review relevant for understanding the conditions through which legality might make a difference in addressing critical challenges
Micro-evolutionary diversification among Indian Ocean parrots: temporal and spatial changes in phylogenetic diversity as a consequence of extinction and invasion
Almost 90% of global bird extinctions have occurred on islands. The loss of endemic spe- cies from island systems can dramatically alter evolutionary trajectories of insular species biodiversity, resulting in a loss of evolutionary diversity important for species adaptation to changing environments. The Western Indian Ocean islands have been the scene of evolution for a large number of endemic parrots. Since their discovery in the 16th cen- tury, many of these parrots have become extinct or have declined in numbers. Alongside the extinction of species, a number of the Indian Ocean islands have experienced coloni- zation by highly invasive parrots, such as the Ring-necked Parakeet Psittacula krameri. Such extinctions and invasions can, on an evolutionary timescale, drive changes in spe- cies composition, genetic diversity and turnover in phylogenetic diversity, all of which can have important impacts on species potential for adaptation to changing environmen- tal and climatic conditions. Using mtDNA cytochrome b data, we resolve the taxonomic placement of three extinct Indian Ocean parrots: the Rodrigues Psittacula exsul, Sey- chelles Psittacula wardi and Reunion Parakeets Psittacula eques. This case study quantifies how the extinction of these species has resulted in lost historical endemic phylogenetic diversity and reduced levels of species richness, and illustrates how it is being replaced by non-endemic invasive forms such as the Ring-necked Parakeet. Finally, we use our phylogenetic framework to identify and recommend a number of phylogenetically appro- priate ecological replacements for the extinct parrots. Such replacements may be intro- duced once invasive forms have been cleared, to rejuvenate ecosystem function and restore lost phylogenetic diversity
Recycling bins, garbage cans or think tanks? Three myths regarding policy analysis institutes
The phrase 'think tank' has become ubiquitous – overworked and underspecified – in the political lexicon. It is entrenched in scholarly discussions of public policy as well as in the 'policy wonk' of journalists, lobbyists and spin-doctors. This does not mean that there is an agreed definition of think tank or consensual understanding of their roles and functions. Nevertheless, the majority of organizations with this label undertake policy research of some kind. The idea of think tanks as a research communication 'bridge' presupposes that there are discernible boundaries between (social) science and policy. This paper will investigate some of these boundaries. The frontiers are not only organizational and legal; they also exist in how the 'public interest' is conceived by these bodies and their financiers. Moreover, the social interactions and exchanges involved in 'bridging', themselves muddy the conception of 'boundary', allowing for analysis to go beyond the dualism imposed in seeing science on one side of the bridge, and the state on the other, to address the complex relations between experts and public policy
The lower airway microbiome in paediatric health and chronic disease
The advent of next generation sequencing has rapidly challenged the paediatric respiratory physician’s understanding of lung microbiology and the role of the lung microbiome in host health and disease. In particular, the role of “microbial key players” in paediatric respiratory disease is yet to be fully explained. Accurate profiling of the lung microbiome in children is challenging since the ability to obtain lower airway samples coupled with processing “low-biomass specimens” are both technically difficult. Many studies provide conflicting results.
Early microbiota-host relationships may be predictive of the development of chronic respiratory disease but attempts to correlate lower airway microbiota in premature infants and risk of developing bronchopulmonary dysplasia (BPD) have produced mixed results. There are differences in lung microbiota in asthma and cystic fibrosis (CF). The increased abundance of oral taxa in the lungs may (or may not) promote disease processes in asthma and CF. In CF, correlation between microbiota diversity and respiratory decline is commonly observed. When one considers other pathogens beyond the bacterial kingdom, the contribution and interplay of fungi and viruses within the lung microbiome further increase complexity. Similarly, the interaction between microbial communities in different body sites, such as the gut-lung axis, and the influence of environmental factors, including diet, make the co-existence of host and microbes ever more complicated. Future, multi-omics approaches may help uncover novel microbiome-based biomarkers and therapeutic targets in respiratory disease and explain how we can live in harmony with our microbial companions
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