892 research outputs found
Benthic biomass size spectra in shelf and deep-sea sediments
The biomass distributions of marine benthic metazoans (meio- to macro-fauna, 1 ?g–32 mg wet weight) across three contrasting sites were investigated to test the hypothesis that allometry can consistently explain observed trends in biomass spectra. Biomass (and abundance) size spectra were determined from observations made at the Faroe–Shetland Channel (FSC) in the Northeast Atlantic (water depth 1600 m), the Fladen Ground (FG) in the North Sea (150 m), and the hypoxic Oman Margin (OM) in the Arabian Sea (500 m). Observed biomass increased with body size as a power law at FG (scaling exponent, b = 0.16) and FSC (b = 0.32), but less convincingly at OM (b = 0.12 but not significantly different from 0). A simple model was constructed to represent the same 16 metazoan size classes used for the observed spectra, all reliant on a common detrital food pool, and allowing the three key processes of ingestion, respiration and mortality to scale with body size. A micro-genetic algorithm was used to fit the model to observations at the sites. The model accurately reproduces the observed scaling without needing to include the effects of local influences such as hypoxia. Our results suggest that the size-scaling of mortality and ingestion are dominant factors determining the distribution of biomass across the meio- to macrofaunal size range in contrasting marine sediment communities. Both the observations and the model results are broadly in agreement with the "metabolic theory of ecology" in predicting a quarter power scaling of biomass across geometric body size classes
iPhone video link FaceTime as an orientation tool: Remote O&M for people with vision impairment
Report of the SNOMS Project 2006 to 2012, SNOMS SWIRE NOCS Ocean Monitoring System. Part 1: Narrative description
The ocean plays a major role in controlling the concentration of carbon dioxide (CO2) in the atmosphere. Increasing concentrations of CO2 in the atmosphere are a threat to the stability of the earth’s climate. A better understanding of the controlling role of the ocean will improve predictions of likely future changes in climate and the impact of the uptake of CO2 itself on marine eco-systems caused by the associated acidification of the ocean waters. The SNOMS Project (SWIRE NOCS Ocean Monitoring System) is a ground breaking joint research project supported by the Swire Group Trust, the Swire Educational Trust, the China Navigation Company (CNCo) and the Natural Environment Research Council. It collects high quality data on concentrations of CO2 in the surface layer of the ocean. It contributes to the international effort to better quantify (and understand the driving processes controlling) the exchanges of CO2 between the ocean and the atmosphere. In 2006 and 2007 a system that could be used on a commercial ship to provide data over periods of several months with only limited maintenance by the ships crew was designed and assembled by NOCS. The system was fitted to the CNCo ship the MV Pacific Celebes in May 2007. The onboard system was supported by web pages that monitored the progress of the ship and the functioning of the data collection system. To support the flow of data from the ship to the archiving of the data at the Carbon Dioxide Information Analysis Center (CDIAC in the USA) data processing procedures were developed for the quality control and systematic handling of the data. Data from samples of seawater collected by the ships crew and analysed in NOC (730 samples) have been used to confirm the consistency of the data from the automated measurement system on the ship. To examine the data collected between 2007 and 2012 the movements of the ship are divided into 16 voyages. Initially The Celebes traded on a route circum-navigating the globe via the Panama and Suez Canals. In 2009 the route shifted to one between Australia and New Zealand to USA and Canada. Analysis of the data is an on going process. It has demonstrated that the system produces reliable data. Data are capable of improving existing estimates of seasonal variability. The work has improved knowledge of gas exchange processes. Data from the crew-collected-samples are helping improve our ability to estimate alkalinity in different areas. This helps with the study of ocean acidification. Data from the 9 round trips in the Pacific are currently being examined along with data made available by the NOAA-PMEL laboratory forming time series from 2004 to 2012. The data from the Pacific route are of considerable interest. One reason is that the data monitors variations in the fluxes of CO2 associated with the current that flows westwards along the equator. This is one of the major natural sources of CO2 from the ocean into the atmosphere
On the Origin of Traveling Pulses in Bistable Systems
The interaction between a pair of Bloch fronts forming a traveling domain in
a bistable medium is studied. A parameter range beyond the nonequilibrium
Ising-Bloch bifurcation is found where traveling domains collapse. Only beyond
a second threshold the repulsive front interactions become strong enough to
balance attractive interactions and asymmetries in front speeds, and form
stable traveling pulses. The analysis is carried out for the forced complex
Ginzburg-Landau equation. Similar qualitative behavior is found in the bistable
FitzHugh-Nagumo model.Comment: 5 pages, RevTeX. Aric Hagberg: http://t7.lanl.gov/People/Aric/; Ehud
Meron:http://www.bgu.ac.il/BIDR/research/staff/meron.htm
A transdisciplinary approach to a conservation crisis: a case study of the Eurasian curlew (Numenius arquata) in Ireland
In this article, we build on a growing literature of examples of transdisciplinary approaches to illustrate the catalysts and outcomes of a stakeholder‐driven process to conservation practice. We illustrate this using the case of one of Europe's most rapidly declining bird species, the Eurasian curlew (Numenius arquata ). As part of the response to its continuing decline, a stakeholder‐driven workshop was held in Ireland in November 2016, bringing together over 80 stakeholders from a range of governmental, non‐governmental, and private organizations responsible for or interested in curlew conservation and management. This innovative workshop sought to formulate ideas and support the implementation of actions from stakeholders themselves on how to halt further losses of curlews, within the current legislative framework. Four years on, many of the short‐ and medium‐term actions identified during the workshop have been implemented jointly by stakeholders. However, curlew recovery will require continued communication and meaningful engagement with all relevant stakeholders together with increased government support underpinned by increased public awareness and ownership of the curlew's plight. Ultimately, many stakeholders will measure the success of curlew conservation in Ireland by the long‐term viability of the breeding population
Development of the OPgun™ for bombardment of animal tissues
A simple and inexpensive particle-bombardment device, the OPgun™, was constructed for the
delivery of DNA into animal tissues. This device is based on the particle-inflow gun first described
for plant-cell transfection. The delivery of tungsten particles into the epidermis of the mouse ear,
without the use of vacuum and without causing damage to the tissue, was demonstrated. The system
was also shown to be capable of inducing antibodies to a foreign gene in mice.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi.
Adobe Acrobat X Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format
Hard Dense Loops in a Cold Non-Abelian Plasma
Classical transport theory is used to study the response of a non-Abelian
plasma at zero temperature and high chemical potential to weak color
electromagnetic fields. In this article the parallelism between the transport
phenomena occurring in a non-Abelian plasma at high temperature and high
density is stressed. Particularly, it is shown that at high densities it is
also possible to relate the transport equations to the zero-curvature condition
of a Chern-Simons theory in three dimensions, even when quarks are not
considered ultrarelativistic. The induced color current in the cold plasma can
be expressed as an average over angles, which represent the directions of the
velocity vectors of quarks having Fermi energy. From this color current it is
possible to compute -point gluonic amplitudes, with arbitrary . It is
argued that these amplitudes are the same as the ones computed in the high
chemical potential limit of QCD, that are then called hard dense loops. The
agreement between the two different formalisms is checked by computing the
polarization tensor of QED due to finite density effects in the high density
limit.Comment: 16 pages, Revtex, final version to appear in Phys. Rev. D with minor
correction
Transcriptome profiling on the response of Mycosphaerella graminicola isolates to an azole fungicide using cDNA arrays
Resistance to azole antifungals is a major problem in the control of diseases caused by fungal pathogens of both humans and plants. Potential for the development of azole resistance in the wheat leaf blotch pathogen Mycosphaerella graminicola, the causal agent of the most economically significant foliar disease of wheat in north-western Europe, is now of particular concern after the recent emergence of widespread resistance to quinone outside inhibitor fungicides. Using a cDNA microarray representing around 25% of the genome, we have profiled the transcriptional response of M. graminicola to epoxiconazole, currently the most widely used azole fungicide on cereal crops. By comparing the transcription profiles of two M. graminicola isolates with contrasting sensitivities to epoxiconazole we show qualitative and quantitative differences in differentially expressed genes, including those involved in ergosterol biosynthesis, mitochondrial respiration and transport mechanisms. This represents the first study investigating the response of a plant pathogenic fungus to a fungicide using cDNA microarray technology
Eating Well While Dining Out: Collaborating with Local Restaurants to Promote Heart Healthy Menu Items
Background: Because Americans commonly consume restaurant foods with poor dietary quality, effective interventions are needed to improve food choices at restaurants. Purpose: The purpose of this study was to design and evaluate a restaurant-based intervention to help customers select and restaurants promote heart healthy menu items with healthful fats and high-quality carbohydrates. Methods: The intervention included table tents outlining 10 heart healthy eating tips, coupons promoting healthy menu items, an information brochure, and link to study website. Pre- and postintervention surveys were completed by restaurant managers and customers completed a brief “intercept” survey. Results: Managers (n = 10) reported that the table tents and coupons were well received, and several noted improved personal nutrition knowledge. Overall, 4214 coupons were distributed with 1244 (30%) redeemed. Of 300 customers surveyed, 126 (42%) noticed the table tents and, of these, 115 (91%) considered the nutrition information helpful, 42 (33%) indicated that the information influenced menu items purchased, and 91 (72%) reported that the information will influence what they order in the future. Discussion: The intervention was well received by restaurant managers and positively influenced menu item selection by many customers. Translation to Health Education Practice: Further research is needed to assess effective strategies for scaling up and sustaining this intervention approach
Breakup of F on Pb near the Coulomb barrier
Angular distributions of oxygen produced in the breakup of F incident
on a Pb target have been measured around the grazing angle at beam
energies of 98 and 120 MeV. The data are dominated by the proton stripping
mechanism and are well reproduced by dynamical calculations. The measured
breakup cross section is approximately a factor of 3 less than that of fusion
at 98 MeV. The influence of breakup on fusion is discussed.Comment: 7 pages, 8 figure
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