249 research outputs found
Concert recording 2015-04-27
[Track 01]. Blue caprice / Victor Morosco -- [Track 02]. Concerto for Stan Getz. Con fuoco ; [Track 03]. Elegy ; [Track 04]. Con brio / Richard Rodney Bennett -- [Track 05]. Sonata for alto sax and piano. I ; [Track 06]. Slowly ; Medium fast ; Freely - fast / Phil Woods
Confronting Global Warming: Maine’s Multi-Sector Initiatives, 2003–2008
David Littell, Gary Westerman and Malcolm Burson describe Maine’s pioneering efforts in reducing greenhouse gas emissions, promoting energy efficiency, and developing less carbon-intensive and more sustainable energy sources. They discuss in particular the goals and accomplishments of the state’s Climate Action Plan and Maine’s participation in several multi-state and regional efforts, including the Regional Greenhouse Gas Initiative (RGGI)
From Ecological Stoichiometry to Biochemical Composition: Variation in N and P Supply Alters Key Biosynthetic Rates in Marine Phytoplankton
One of the major challenges in ecological stoichiometry is to establish how environmental changes in resource availability may affect both the biochemical composition of organisms and the species composition of communities. This is a pressing issue in many coastal waters, where anthropogenic activities have caused large changes in riverine nutrient inputs. Here we investigate variation in the biochemical composition and synthesis of amino acids, fatty acids (FA), and carbohydrates in mixed phytoplankton communities sampled from the North Sea. The communities were cultured in chemostats supplied with different concentrations of dissolved inorganic nitrogen (DIN) and phosphorus (DIP) to establish four different types of resource limitations. Diatoms dominated under N-limited, N+P limited and P-limited conditions. Cyanobacteria became dominant in one of the N-limited chemostats and green algae dominated in the one P-limited chemostat and under light-limited conditions. Changes in nutrient availability directly affected amino acid content, which was lowest under N and N+P limitation, higher under P-limitation and highest when light was the limiting factor. Storage carbohydrate content showed the opposite trend and storage FA content seemed to be co-dependent on community composition. The synthesis of essential amino acids was affected under N and N+P limitation, as the transformation from non-essential to essential amino acids decreased at DIN:DIP ≤ 6. The simple community structure and clearly identifiable nutrient limitations confirm and clarify previous field findings in the North Sea. Our results show that different phytoplankton groups are capable of adapting their key biosynthetic rates and hence their biochemical composition to different degrees when experiencing shifts in nutrient availability. This will have implications for phytoplankton growth, community structure, and the nutritional quality of phytoplankton as food for higher trophic levels
Stable coexistence of equivalent nutrient competitors through niche differentiation in the light spectrum
Niche?based theories and the neutral theory of biodiversity differ in their predictions of how the species composition of natural communities will respond to changes in nutrient availability. This is an issue of major environmental relevance, as many ecosystems have experienced changes in nitrogen (N) and phosphorus (P) due to anthropogenic manipulation of nutrient loading. To understand how changes in N and P limitation may impact community structure, we conducted laboratory competition experiments using a multispecies phytoplankton community sampled from the North Sea. Results showed that picocyanobacteria (Cyanobium sp.) won the competition under N limitation, while picocyanobacteria and nonmotile nanophytoplankton (Nannochloropsis sp.) coexisted at equal abundances under P limitation. Additional experiments using isolated monocultures confirmed that Cyanobium sp. depleted N to lower levels than Nannochloropsis sp., but that both species had nearly identical P requirements, suggesting a potential for neutral coexistence under P?limited conditions. Pairwise competition experiments with the two isolates seemed to support the consistency of these results, but P limitation resulted in stable species coexistence irrespective of the initial conditions rather than the random drift of species abundances predicted by neutral theory. Comparison of the light absorption spectra indicates that coexistence of the two species was stabilized through differential use of the underwater light spectrum. Our results provide an interesting experimental example of modern coexistence theory, where species were equal competitors in one niche dimension but their competitive traits differed in other niche dimensions, thus enabling stable species coexistence on a single limiting nutrient through niche differentiation in the light spectrum
High-fidelity conformation of graphene to SiO2 topographic features
Strain engineering of graphene through interaction with a patterned substrate
offers the possibility of tailoring its electronic properties, but will require
detailed understanding of how graphene's morphology is determined by the
underlying substrate. However, previous experimental reports have drawn
conflicting conclusions about the structure of graphene on SiO2. Here we show
that high-resolution non-contact atomic force microscopy of SiO2 reveals
roughness at the few-nm length scale unresolved in previous measurements, and
scanning tunneling microscopy of graphene on SiO2 shows it to be slightly
smoother than the supporting SiO2 substrate. Quantitative analysis of the
competition between bending rigidity of the graphene and adhesion to the
substrate explains the observed roughness of monolayer graphene on SiO2 as
extrinsic, and provides a natural, intuitive description in terms of highly
conformal adhesion. The analysis indicates that graphene adopts the
conformation of the underlying substrate down to the smallest features with
nearly 99% fidelity.Comment: 13 pages, 3 figures plus supplemental informatio
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A simplified model of aerosol removal by natural processes in reactor containments
Simplified formulae are developed for estimating the aerosol decontamination that can be achieved by natural processes in the containments of pressurized water reactors and in the drywells of boiling water reactors under severe accident conditions. These simplified formulae were derived by correlation of results of Monte Carlo uncertainty analyses of detailed models of aerosol behavior under accident conditions. Monte Carlo uncertainty analyses of decontamination by natural aerosol processes are reported for 1,000, 2,000, 3,000, and 4,000 MW(th) pressurized water reactors and for 1,500, 2,500, and 3,500 MW(th) boiling water reactors. Uncertainty distributions for the decontamination factors and decontamination coefficients as functions of time were developed in the Monte Carlo analyses by considering uncertainties in aerosol processes, material properties, reactor geometry and severe accident progression. Phenomenological uncertainties examined in this work included uncertainties in aerosol coagulation by gravitational collision, Brownian diffusion, turbulent diffusion and turbulent inertia. Uncertainties in aerosol deposition by gravitational settling, thermophoresis, diffusiophoresis, and turbulent diffusion were examined. Electrostatic charging of aerosol particles in severe accidents is discussed. Such charging could affect both the coagulation and deposition of aerosol particles. Electrostatic effects are not considered in most available models of aerosol behavior during severe accidents and cause uncertainties in predicted natural decontamination processes that could not be taken in to account in this work. Median (50%), 90 and 10% values of the uncertainty distributions for effective decontamination coefficients were correlated with time and reactor thermal power. These correlations constitute a simplified model that can be used to estimate the decontamination by natural aerosol processes at 3 levels of conservatism. Applications of the model are described
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Accident source terms for Light-Water Nuclear Power Plants. Final report
In 1962 tile US Atomic Energy Commission published TID-14844, ``Calculation of Distance Factors for Power and Test Reactors`` which specified a release of fission products from the core to the reactor containment for a postulated accident involving ``substantial meltdown of the core``. This ``source term``, tile basis for tile NRC`s Regulatory Guides 1.3 and 1.4, has been used to determine compliance with tile NRC`s reactor site criteria, 10 CFR Part 100, and to evaluate other important plant performance requirements. During the past 30 years substantial additional information on fission product releases has been developed based on significant severe accident research. This document utilizes this research by providing more realistic estimates of the ``source term`` release into containment, in terms of timing, nuclide types, quantities and chemical form, given a severe core-melt accident. This revised ``source term`` is to be applied to the design of future light water reactors (LWRs). Current LWR licensees may voluntarily propose applications based upon it
Use of social networks as a CSR communication tool
The aim of this paper is to analyse the use of online social networks as a tool
for Corporate Social Responsibility (CSR) communication and management. To this
end, an analysis was performed of the messages posted by the 20 Spanish companies
with the highest market capitalisation and the responses that they received on two
of the most popular online social networks, Facebook and Twitter. The results of the
analysis of these data show that the tendency has been to use social networks for the
one-way communication of aspects of CSR related with the organisation. Therefore, it
is necessary to change the way companies communicate their CSR issues by shifting
to a two-way communication approach, as has been the case in other kinds of enterprise
relations with their stakeholders.The authors received no direct funding for this research
Publication of data collection forms from NHLBI funded sickle cell disease implementation consortium (SCDIC) registry
Background: Sickle cell disease (SCD) is an autosomal recessive blood disorder affecting approximately 100,000 Americans and 3.1 million people globally. The scarcity of relevant knowledge and experience with rare diseases creates a unique need for cooperation and infrastructure to overcome challenges in translating basic research advances into clinical advances. Despite registry initiatives in SCD, the unavailability of descriptions of the selection process and copies of final data collection tools, coupled with incomplete representation of the SCD population hampers further research progress. This manuscript describes the SCDIC (Sickle Cell Disease Implementation Consortium) Registry development and makes the SCDIC Registry baseline and first follow-up data collection forms available for other SCD research efforts.
Results: Study data on 2400 enrolled patients across eight sites was stored and managed using Research Electronic Data Capture (REDCap). Standardized data collection instruments, recruitment and enrollment were refined through consensus of consortium sites. Data points included measures taken from a variety of validated sources (PHENX, PROMIS and others). Surveys were directly administered by research staff and longitudinal follow-up was coordinated through the DCC. Appended registry forms track medical records, event-related patient invalidation, pregnancy, lab reporting, cardiopulmonary and renal functions.
Conclusions: The SCDIC Registry strives to provide an accurate, updated characterization of the adult and adolescent SCD population as well as standardized, validated data collecting tools to guide evidence-based research and practice
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