A Comparison of Risk Exposure in Aquaculture and Agricultural Businesses

Agriculture and aquaculture have common features associated with their biological nature affecting risk exposure of the businesses. The aim of this paper is to compare risk exposure in salmon farming and agricultural enterprises in Norway by using an implicit error component model to examine the risk structure of yields, prices and economic returns at the farm level. Results indicate a higher farm-level year-to-year variability in yields, prices and economic returns in salmon farming than in agricultural enterprises. The variability in livestock enterprises was generally lower than for crop enterprises. Return on assets was highest in salmon farming with an average annual return of 9.2%. All of the agricultural farm types exhibited a negative average return on assets on average. Stochastic dominance tests of the distribution of economic returns from aquaculture and agricultural farm types showed salmon farming to be the most risk efficient alternative and salmon farming was most attractive from an investor’s perspective.Risk analysis, variability, Norway, Risk and Uncertainty,

Nighttime observations of thunderstorm electrical activity from a high altitude airplane

Nocturnal thunderstorms were observed from above and features of cloud structure and lightning which are not generally visible from the ground are discussed. Most, lightning activity seems to be associated with clouds with strong convective cauliflower tops. In both of the storms lightning channels were visible in the clear air above the cloud. It is shown that substances produced by thunderstorm electrical discharges can be introduced directly into the stratosphere. The cause and nature of the discharges above the cloud are not clear. They may be produced by accumulations of space charge in the clear air above the cloud. The discharges may arise solely because of the intense electric fields produced by charges within the cloud. In the latter case the ions introduced by these discharges will increase the electrical conductivity of the air above the cloud and increase the conduction current that flows from the cloud to the electrosphere. More quantitative data at higher resolution may show significant spectral differences between cloud to ground and intracloud strokes. It is shown that electric field change data taken with an electric field change meter mounted in an airplane provide data on lightning discharges from above that are quite similar to those obtained from the ground in the past. The optical signals from dart leaders, from return strokes, and from continuing currents are recognizable, can be used to provide information on the fine structure of lightning, and can be used to distinguish between cloud to ground and intracloud flashes

Quality of life of chronic stable angina patients 4 years after coronary angioplasty or coronary artery bypass surgery

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72244/1/j.1365-2796.2001.00782.x.pd

Diatom Proteomics Reveals Unique Acclimation Strategies to Mitigate Fe Limitation

Phytoplankton growth rates are limited by the supply of iron (Fe) in approximately one third of the open ocean, with major implications for carbon dioxide sequestration and carbon (C) biogeochemistry. To date, understanding how alteration of Fe supply changes phytoplankton physiology has focused on traditional metrics such as growth rate, elemental composition, and biophysical measurements such as photosynthetic competence (Fv/Fm). Researchers have subsequently employed transcriptomics to probe relationships between changes in Fe supply and phytoplankton physiology. Recently, studies have investigated longer-term (i.e. following acclimation) responses of phytoplankton to various Fe conditions. In the present study, the coastal diatom, Thalassiosira pseudonana, was acclimated (10 generations) to either low or high Fe conditions, i.e. Fe-limiting and Fe-replete. Quantitative proteomics and a newly developed proteomic profiling technique that identifies low abundance proteins were employed to examine the full complement of expressed proteins and consequently the metabolic pathways utilized by the diatom under the two Fe conditions. A total of 1850 proteins were confidently identified, nearly tripling previous identifications made from differential expression in diatoms. Given sufficient time to acclimate to Fe limitation, T. pseudonana up-regulates proteins involved in pathways associated with intracellular protein recycling, thereby decreasing dependence on extracellular nitrogen (N), C and Fe. The relative increase in the abundance of photorespiration and pentose phosphate pathway proteins reveal novel metabolic shifts, which create substrates that could support other well-established physiological responses, such as heavily silicified frustules observed for Fe-limited diatoms. Here, we discovered that proteins and hence pathways observed to be down-regulated in short-term Fe starvation studies are constitutively expressed when T. pseudonana is acclimated (i.e., nitrate and nitrite transporters, Photosystem II and Photosystem I complexes). Acclimation of the diatom to the desired Fe conditions and the comprehensive proteomic approach provides a more robust interpretation of this dynamic proteome than previous studies.This work was supported by National Science Foundation grants OCE1233014 (BLN) and the Office of Polar Programs Postdoctoral Fellowship grant 0444148 (BLN). DRG was supported by National Institutes of Health 5P30ES007033-10. AH and MTM were supported by Natural Sciences and Engineering Research Council of Canada. RFS and PWB were supported by the New Zealand Royal Society Marsden Fund and the Ministry of Science. This work is supported in part by the University of Washington's Proteomics Computer Resource Centre (UWPR95794). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Identifying and Tracking Proteins Through the Marine Water Column: Insights Into the Inputs and Preservation Mechanisms of Protein in Sediments

Proteins generated during primary production represent an important fraction of marine organic nitrogen and carbon, and have the potential to provide organism-specific information in the environment. The Bering Sea is a highly productive system dominated by seasonal blooms and was used as a model system for algal proteins to be tracked through the water column and incorporated into detrital sedimentary material. Samples of suspended and sinking particles were collected at multiple depths along with surface sediments on the continental shelf and deeper basin of the Bering Sea. Modified standard proteomic preparations were used in conjunction with high pressure liquid chromatography-tandem mass spectrometry to identify the suite of proteins present and monitor changes in their distribution. In surface waters 207 proteins were identified, decreasing through the water column to 52 proteins identified in post-bloom shelf surface sediments and 24 proteins in deeper (3490 m) basin sediments. The vast majority of identified proteins in all samples were diatom in origin, reflecting their dominant contribution of biomass during the spring bloom. Identified proteins were predominantly from metabolic, binding/structural, and transport-related protein groups. Significant linear correlations were observed between the number of proteins identified and the concentration of total hydrolysable amino acids normalized to carbon and nitrogen. Organelle-bound, transmembrane, photosynthetic, and other proteins involved in light harvesting were preferentially retained during recycling. These findings suggest that organelle and membrane protection represent important mechanisms that enhance the preservation of protein during transport and incorporation into sediments

Primary care consultations and costs among HIV-positive individulas in UK primary care 1995-2005: a cohort study

Objectives: To investigate the role of primary care in the management of HIV and estimate primary care-associated costs at a time of rising prevalence. Methods: Retrospective cohort study between 1995 and 2005, using data from general practices contributing data to the UK General Practice Research Database. Patterns of consultation and morbidity and associated consultation costs were analysed among all practice-registered patients for whom HIV-positive status was recorded in the general practice record. Results: 348 practices yielded 5504 person-years (py) of follow-up for known HIV-positive patients, who consult in general practice frequently (4.2 consultations/py by men, 5.2 consultations/py by women, in 2005) for a range of conditions. Consultation rates declined in the late 1990s from 5.0 and 7.3 consultations/py in 1995 in men and women, respectively, converging to rates similar to the wider population. Costs of consultation (general practitioner and nurse, combined) reflect these changes, at £100.27 for male patients and £117.08 for female patients in 2005. Approximately one in six medications prescribed in primary care for HIV-positive individuals has the potential for major interaction with antiretroviral medications. Conclusion: HIV-positive individuals known in general practice now consult on a similar scale to the wider population. Further research should be undertaken to explore how primary care can best contribute to improving the health outcomes of this group with chronic illness. Their substantial use of primary care suggests there may be potential to develop effective integrated care pathways

Protein Recycling in Bering Sea Algal Incubations

Protein present in phytoplankton represents a large fraction of the organic nitrogen and carbon transported from its synthesis in surface waters to marine sediments. Yet relatively little is known about the longevity of identifiable protein in situ, or the potential modifications to proteins that occur during bloom termination, protein recycling and degradation. To address this knowledge gap, diatom-dominated phytoplankton was collected during the Bering Sea spring blooms of 2009 and 2010, and incubated under darkness in separate shipboard degradation experiments spanning 11 and 53 d, respectively. In each experiment, the protein distribution was monited over time using shotgun proteomics, along with total hydrolyzable amino acids (THAAs), total protein, particulate organic carbon (POC) and nitrogen (PN), and bacterial cell abundance. Identifiable proteins, total protein and THAAs were rapidly lost during the first 5 d of enclosure in darkness in both incubations. Thereafter the loss rate was slower, and it declined further after 22 d. The initial loss of identifiable biosynthetic, glycolysis, metabolism and translation proteins after 12 h may represent shutdown of cellular activity among algal cells. Additional peptides with glycan modifications were identified in early incubation time points, suggesting that such protein modifications could be used as a marker for internal recycling processes and possibly cell death. Protein recycling was not uniform, with a subset of algal proteins including fucoxanthin chlorophyll binding proteins and RuBisCO identified after 53 d of degradation. Non-metric multidimensional scaling was used to compare the incubations with previous environmental results. The results confirmed recent observations that some fraction of algal proteins can survive water column recycling and undergo transport to marine sediments, thus contributing organic nitrogen to the benthos

Making Galaxies in a Cosmological Context: The Need for Early Stellar Feedback

We introduce the Making Galaxies in a Cosmological Context (MaGICC) program of smoothed particle hydrodynamics (SPH) simulations. We describe a parameter study of galaxy formation simulations of an L* galaxy that uses early stellar feedback combined with supernova feedback to match the stellar mass--halo mass relationship. While supernova feedback alone can reduce star formation enough to match the stellar mass--halo mass relationship, the galaxy forms too many stars before z=2 to match the evolution seen using abundance matching. Our early stellar feedback is purely thermal and thus operates like a UV ionization source as well as providing some additional pressure from the radiation of massive, young stars. The early feedback heats gas to >10^6 K before cooling to 10^4 K. The pressure from this hot gas creates a more extended disk and prevents more star formation prior to z=1 than supernovae feedback alone. The resulting disk galaxy has a flat rotation curve, an exponential surface brightness profile, and matches a wide range of disk scaling relationships. The disk forms from the inside-out with an increasing exponential scale length as the galaxy evolves. Overall, early stellar feedback helps to simulate galaxies that match observational results at low and high redshifts.Comment: 13 pages, 14 figures, accepted MNRAS, movies at http://www.mpia.de/~stinson/magic

Obesity: A Biobehavioral Point of View

Excerpt: If you ask an overweight person, “Why are you fat?’, you will, almost invariably, get the answer, “Because 1 eat too much.” You will get this answer in spite of the fact that of thirteen studies, six find no significant differences in the caloric intake of obese versus nonobese subjects, five report that the obese eat significantly less than the nonobese, and only two report that they eat significantly more