1,714 research outputs found
Neonatal growth of Steller sea lion (Eumetopias jubatus) pups in Alaska
The growth rate of Steller sea lion (Eumetopias jubatus) pups was studied in southeast Alaska, the Gulf of Alaska, and the Aleutian Islands during the first six weeks after birth. The Steller sea lion population is currently stable in southeast Alaska but is declining in the Aleutian Islands and parts of the Gulf of Alaska. Male pups (22.6 kg [±2.21 SD]) were significantly heavier than female pups (19.6 kg [±1.80 SD]) at 1−5 days of age, but there were no significant differences among rookeries. Male and female pups grew (in mass, standard length, and axillary girth) at the same rate. Body mass and standard length increased at a faster rate for pups in the Aleutian Islands and the western Gulf of Alaska (0.45−0.48 kg/day and 0.47−0.53 cm/day, respectively) than in southeast Alaska (0.23 kg/day and 0.20 cm/day). Additionally, axillary girth increased at a faster rate for pups in the Aleutian Islands (0.59 cm/ day) than for pups in southeast Alaska v(0.25 cm/day). Our results indicate a greater maternal investment in male pups during gestation, but not during early lactation. Although differences in pup growth rate occurred among rookeries, there was no evidence that female sea lions and their pups were nutritionally stressed in the area of population declin
Relationship between fish size and otolith length for 63 species of fishes from the Eastern North Pacific Ocean
Otoliths commonly are used to determine the taxon, age, and size of fishes. This information is useful for population management, predator-prey studies, and archaeological research. The relationship between the length of a fish and the length of its otoliths remains unknown for many species of marine fishes in the Pacific Ocean. Therefore, the relationships between fish length and fish weight, and between otolith length and fish length, were developed for 63 species of fishes caught in the eastern North Pacific Ocean. We also summarized similar relationships for 46 eastern North Pacific fish species reported in the literature. The relationship between fish length and otolith length was linear, and most of the variability was explained by a simple least-squares regression (r 2 > 0.700 for 45 of 63 species). The relationship between otolith length and fish length was not significantly different between left and right otoliths for all but one fish species. Images of otoliths from 77 taxa are included to assist in the identification of species. (PDF file contains 38 pages.
An interdisciplinary approach to volcanic risk reduction under conditions of uncertainty: a case study of Tristan da Cunha
The uncertainty brought about by intermittent volcanic activity is fairly common at volcanoes worldwide. While better knowledge of any one volcano's behavioural characteristics has the potential to reduce this uncertainty, the subsequent reduction of risk from volcanic threats is only realised if that knowledge is pertinent to stakeholders and effectively communicated to inform good decision making. Success requires integration of methods, skills and expertise across disciplinary boundaries.
This research project develops and trials a novel interdisciplinary approach to volcanic risk reduction on the remote volcanic island of Tristan da Cunha (South Atlantic). For the first time, volcanological techniques, probabilistic decision support and social scientific methods were integrated in a single study. New data were produced that (1) established no spatio-temporal pattern to recent volcanic activity; (2) quantified the high degree of scientific uncertainty around future eruptive scenarios; (3) analysed the physical vulnerability of the community as a consequence of their geographical isolation and exposure to volcanic hazards; (4) evaluated social and cultural influences on vulnerability and resilience; and (5) evaluated the effectiveness of a scenario planning approach, both as a method for integrating the different strands of the research and as a way of enabling on-island decision makers to take ownership of risk identification and management, and capacity building within their community.
The paper provides empirical evidence of the value of an innovative interdisciplinary framework for reducing volcanic risk. It also provides evidence for the strength that comes from integrating social and physical sciences with the development of effective, tailored engagement and communication strategies in volcanic risk reduction
Recommended from our members
A multi-well plate model of reactive gliosis for high throughput screening of potential CNS therapies
Reactive astrogliosis is an important feature of CNS damage and disease which involves changes in astrocyte phenotype and morphology. In particular, CNS trauma can lead to the formation of a glial scar, a three dimensional (3D) mesh of astrocyte processes that can form a physical and chemical barrier to neuronal regeneration, which is a potential target for CNS drug and cell therapy. However, reactive gliosis is difficult to isolate and monitor in typical animal models of CNS damage. In monolayer culture systems astrocytes adopt a highly reactive phenotype, limiting the range of available models suitable for research in this area.
Our previous 3D cell culture systems allow astrocytes to be maintained with a relatively unreactive phenotype until stimulated, whereupon a classical reactive astrocyte response can be monitored. The aim of the current work is to adapt this approach in order to develop a multi-well plate system to provide a reliable, consistent model of reactive gliosis for high throughput screening and research. Once baseline viability and phenotype of primary rat astrocytes were investigated in these models, reactivity was triggered using treatments such as TGFβ1, as seen in Figure 1, hypoxia and low glucose. Outputs included confocal microscopy and 3D image analysis, Western blotting and RT-PCR to quantify markers such as GFAP and CSPG in test and control gels. Using GFP-labelled astrocytes permitted monitoring of cytoplasmic volume and shape, giving an additional measure of astrocyte hypertrophic response within stimulated conditions. The robust protocol that we have developed can form a basis to investigate astrocyte biology in a highly controlled environment, and to model phenotypic features of astrocytes in both damaged and undamaged CNS. A reproducible multi-well plate system will provide an experimental platform which allows potential CNS therapies to be screened at high-throughput, and the effects of potential modulators of astrocyte reactivity to be investigated simply and systematically
3D geological models and their hydrogeological applications : supporting urban development : a case study in Glasgow-Clyde, UK
Urban planners and developers in some parts of the United Kingdom can now access geodata in an easy-to-retrieve and understandable format. 3D attributed geological framework models and associated GIS outputs, developed by the British Geological Survey (BGS), provide a predictive tool for planning site investigations for some of the UK's largest regeneration projects in the Thames and Clyde River catchments.
Using the 3D models, planners can get a 3D preview of properties of the subsurface using virtual cross-section and borehole tools in visualisation software, allowing critical decisions to be made before any expensive site investigation takes place, and potentially saving time and money. 3D models can integrate artificial and superficial deposits and bedrock geology, and can be used for recognition of major resources (such as water, thermal and sand and gravel), for example in buried valleys, groundwater modelling and assessing impacts of underground mining. A preliminary groundwater recharge and flow model for a pilot area in Glasgow has been developed using the 3D geological models as a framework.
This paper focuses on the River Clyde and the Glasgow conurbation, and the BGS's Clyde Urban Super-Project (CUSP) in particular, which supports major regeneration projects in and around the City of Glasgow in the West of Scotland
Molybdenum dioxide in carbon nanoreactors as a catalytic nanosponge for the efficient desulfurization of liquid fuels
The principle of a “catalytic nanosponge” that combines the catalysis of organosulfur oxidation and sequestration of the products from reaction mixtures is demonstrated. Group VI metal oxide nanoparticles (CrOx, MoOx, WOx) are embedded within hollow graphitized carbon nanofibers (GNFs), which act as nanoscale reaction vessels for oxidation reactions used in the decontamination of fuel. When immersed in a model liquid alkane fuel contaminated with organosulfur compounds (benzothiophene, dibenzothiophene, dimethyldibenzothiophene), it is found that MoO2@GNF nanoreactors, comprising 30 nm molybdenum dioxide nanoparticles grown within the channel of GNFs, show superior abilities toward oxidative desulfurization (ODS), affording over 98% sulfur removal at only 5.9 mol% catalyst loading. The role of the carbon nanoreactor in MoO2@GNF is to enhance the activity and stability of catalytic centers over at least 5 cycles. Surprisingly, the nanotube cavity can selectively absorb and remove the ODS products (sulfoxides and sulfones) from several model fuel systems. This effect is related to an adsorptive desulfurization (ADS) mechanism, which in combination with ODS within the same material, yields a “catalytic nanosponge” MoO2@GNF. This innovative ODS and ADS synergistic functionality negates the need for a solvent extraction step in fuel desulfurization and produces ultralow sulfur fuel
Utilizing qualitative data from nominal groups: Exploring the influences on treatment outcome prioritization with rheumatoid arthritis patients
The nominal group technique generates quantitative data through a process of experts ranking items of interest. This article focuses on the additional collection of qualitative data from nominal groups with rheumatoid arthritis (RA) patients, used to explore the influences on prioritizing treatment outcomes. Across all groups, the top five outcomes with the highest importance scores were identified as: pain; joint damage; fatigue; activities of daily living; and mobility. Qualitative findings showed that the personal impact of RA influenced decisions on how to rank specific outcomes through four domains: disease impact; adaptation to illness; external resources and stressors; and social expectations. © The Author(s) 2011
- …