38 research outputs found
Exploiting CO2:CO correlations from aircraft concentration data in a regional atmospheric inversion
No full textObserved correlations between atmospheric concentrations of CO2 and CO represent potentially powerful information for improving CO2 surface flux estimates through coupled CO2-CO inverse analyses. We explore the value of these correlations in improving estimates of regional CO2 fluxes in east Asia by using aircraft observations of CO2 and CO from the TRACE-P campaign over the NW Pacific in March 2001. Our inverse model uses regional CO2 and CO surface fluxes as the state vector, separating biospheric and combustion contributions to CO2. CO2-CO error correlation coefficients are included in the inversion as off-diagonal entries in the a priori and observation error covariance matrices. We derive error correlations in a priori combustion source estimates of CO2 and CO by propagating error estimates of fuel consumption rates and emission factors. However, we find that these correlations are weak because CO source uncertainties are mostly determined by emission factors. Observed correlations between atmospheric CO2 and CO concentrations imply corresponding error correlations in the chemical transport model used as the forward model for the inversion. These error correlations in excess of 0.7, as derived from the TRACE-P data, enable a coupled CO2-CO inversion to achieve significant improvement over a CO2-only inversion for quantifying regional fluxes of CO2.Earth and Planetary SciencesEngineering and Applied SciencesVersion of Recor
Improved quantification of Chinese carbon fluxes using CO2/CO correlations in Asian outflow
No full text[1] We use observed CO2:CO correlations in Asian outflow from the TRACE-P aircraft campaign (February–April 2001), together with a three-dimensional global chemical transport model (GEOS-CHEM), to constrain specific components of the east Asian CO2 budget including, in particular, Chinese emissions. The CO2/CO emission ratio varies with the source of CO2 (different combustion types versus the terrestrial biosphere) and provides a characteristic signature of source regions and source type. Observed CO2/CO correlation slopes in east Asian boundary layer outflow display distinct regional signatures ranging from 10–20 mol/mol (outflow from northeast China) to 80 mol/mol (over Japan). Model simulations using best a priori estimates of regional CO2 and CO sources from Streets et al. [2003] (anthropogenic), the CASA model (biospheric), and Duncan et al. [2003] (biomass burning) overestimate CO2 concentrations and CO2/CO slopes in the boundary layer outflow. Constraints from the CO2/CO slopes indicate that this must arise from an overestimate of the modeled regional net biospheric CO2 flux. Our corrected best estimate of the net biospheric source of CO2 from China for March–April 2001 is 3200 Gg C/d, which represents a 45 % reduction of the net flux from the CASA model. Previous analyses of the TRACE-P data had found that anthropogenic Chinese C
Comparison of chemical characteristics of 495 biomass burning plumes intercepted by the NASA DC-8 aircraft during the ARCTAS/CARB-2008 field campaign
No full textThis paper compares measurements of gaseous and particulate emissions from a wide range of biomass-burning plumes intercepted by the NASA DC-8 research aircraft during the three phases of the ARCTAS-2008 experiment: ARCTAS-A, based out of Fairbanks, Alaska, USA (3 April to 19 April 2008); ARCTAS-B based out of Cold Lake, Alberta, Canada (29 June to 13 July 2008); and ARCTAS-CARB, based out of Palmdale, California, USA (18 June to 24 June 2008). Approximately 500 smoke plumes from biomass burning emissions that varied in age from minutes to days were segregated by fire source region and urban emission influences. The normalized excess mixing ratios (NEMR) of gaseous (carbon dioxide, acetonitrile, hydrogen cyanide, toluene, benzene, methane, oxides of nitrogen and ozone) and fine aerosol particulate components (nitrate, sulfate, ammonium, chloride, organic aerosols and water soluble organic carbon) of these plumes were compared. A detailed statistical analysis of the different plume categories for different gaseous and aerosol species is presented in this paper.
The comparison of NEMR values showed that CH4 concentrations were higher in air-masses that were influenced by urban emissions. Fresh biomass burning plumes mixed with urban emissions showed a higher degree of oxidative processing in comparison with fresh biomass burning only plumes. This was evident in higher concentrations of inorganic aerosol components such as sulfate, nitrate and ammonium, but not reflected in the organic components. Lower NOx NEMRs combined with high sulfate, nitrate and ammonium NEMRs in aerosols of plumes subject to long-range transport, when comparing all plume categories, provided evidence of advanced processing of these plumes
Phenotypic differences between hatchery-reared and wild mud crabs, Scylla Serrata, and the effects of conditioning
No full textHatchery-reared animals for stock enhancement should be competent to survive and grow at rates equivalent to those of wild conspecifics. However, morphological differences are often observed, and pre-conditioning steps may be required to improve the fitness of hatchery-reared juveniles prior to release. In the present study, hatchery-reared Scylla serrata juveniles were reared either individually (HR-solitary) or groups in tanks (HR-communal), the latter group being exposed to intraspecific competition and foraging for food. After 21 days, both groups were compared to similar size wild-caught juveniles in terms of morphometric measurements of carapace spination, abnormalities and carapace colouration. There were some limited significant differences between HR-communal crabs and HR-solitary crabs in terms of length of 8th and 9th lateral spines and in body-weight-carapace width ratio, but both treatments differed from wild crabs, which were heavier and had longer carapace spines for theiHatchery-reared animals for stock enhancement should be competent to survive and grow at rates equivalent to those of wild conspecifics. However, morphological differences are often observed, and pre-conditioning steps may be required to improve the fitness of hatchery-reared juveniles prior to release. In the present study, hatchery-reared Scylla serrata juveniles were reared either individually (HR-solitary) or groups in tanks (HR-communal), the latter group being exposed to intraspecific competition and foraging for food. After 21 days, both groups were compared to similar size wild-caught juveniles in terms of morphometric measurements of carapace spination, abnormalities and carapace colouration. There were some limited significant differences between HR-communal crabs and HR-solitary crabs in terms of length of 8th and 9th lateral spines and in body-weight-carapace width ratio, but both treatments differed from wild crabs, which were heavier and had longer carapace spines for their size. In contrast, both HR treatments exhibited common abnormalities including deformities in the shape of the abdomen, in particular occurrence of an asymmetrical telson or a deeply folded telson. In all cases, abnormalities persisted through moulting. Initially, carapace colour differed in all measures of colour between HR and wild crabs. However, these differences reduced after a period of 4–8 days of conditioning on coloured tank backgrounds or dark sand or mud backgrounds, without moulting. Similarly, hatchery-reared crabs exhibited very limited burying behaviour on first exposure to sediment, but this increased to levels observed in wild crabs within 2–4 days. Thus, short-term conditioning of hatchery-reared crabs on dark sediments may be effective in increasing predator avoidance and survivorship in released animals, and present results suggest that this can be achieved after relatively short periods of 1 week or less.This study was supported by a European Social Fund (ESF) grant to L. Parkes. The first author acknowledges the assistance of the SEAFDEC/AQD Crustacean Hatchery staff for the experimental set-up and animal husbandry and Dr. Fe Estepa for his help with the statistical analysis
El científico frente a la “crisis” de la civilización. Una aproximación a La incógnita del hombre de Alexis Carrel.. Cuicuilco Revista de la Escuela Nacional de Antropología e Historia: Raza, fobias e intolerancias. Num. 31 (2004) Vol. 11 mayo-agosto
No full textEn el artículo se examinan la obra y el legado del francés Alexis Carrel (1873-1944), ganador del Premio Nobel, como caso paradigmático del modernismo reaccionario y el pesimismo cultural del periodo de entreguerras. Preocupado por la "crisis de la civilización", en 1935 Carrel publicó La incógnita del hombre, un libro en el que proponía la reconstrucción del individuo a partir de un conjunto de medidas fascistas y eugenésicas. El éxito de la obra convirtió a su autor en uno de los divulgadores del racismo científico más populares de la época. Entre 1941 y 1944 trabajó para el régimen colaboracionista de Vichy dirigiendo un instituto de investigaciones sociobiológicas que tenía por misión "mejorar" la población. Tras su muerte, y pese a haber apoyado explícitamente la política biológicoracial de Hitler, Carrel ha sido reivindicado con propósitos de lo más diversos, desde el humanismo católico y la clonación hasta el racismo antiárabe y el fundamentalismo islámico.The article examines the career and legacy of the French-born Nobel laureate Alexis Carrel (1873-1944) as a paradigmatic case of interwar reactionary modernism and cultural despair. Concerned about the "crisis of civilization", in 1935 Carrel published Man, the Unknown, a book in which he proposed the reconstruction of the individual along fascist and eugenic lines. The book´s success turned the author into one of the most popular vulgarizers of scientific racism. Between 1941 and 1944 he worked for the collaborationist regime of Vichy, heading an institution of sociobiological research aimed at the "improvement" of the population. After his death, and despite his endorsement of Nazi racialbiological policies, Carrel has been claimed for widely different purposes, from cloning research to anti-Arab racism and Islamic fundamentalism.Adams, Mark B. (ed.) 1990. The Wellborn Science: Eugenics in Germany, France, Brazil, and Russia, Nueva York, Oxford University Press.Ali, Tariq. 2002. The Clash of Fundamentalisms, Nueva York, Verso.Alvarez Peláez, Raquel. 1997. Sir Francis Galton, padre de la eugenesia, Madrid, Consejo Superior de Investigaciones Científicas.Antier, Jean-Jacques. 1974. Carrel cet inconnu, París, SOS.Aron, Robert y Andr. Dandieu. 1931. Décadence de la nation française, París, Rieder.Bessières, Albert. 1950. La Destinée humaine devant la science: Alexis Carrel, Pierre Lecomte du Noüy, Charles Nicolle, París, Spes.Bessières, Albert. 1952. Le Voyageur de Lourdes, Alexis Carrel, Bruselas, Foyer Notre-Dame.Black, Antony. 2001. The History of Islamic Political Thought: From the Prophet to the Present, Nueva York, Routledge.Black, Edwin. 2003. The War Against the Weak: Eugenics and America´s Campaign to Create a Master Race, Nueva York, Four Walls Eight Windows.Brun, Gérard. 1985. Technocrates et technocratie en France, París, Editions de l´Ecole des Hautes Etudes en Sciences Sociales.Burleigh, Michael. 1994. Death and Deliverance: “Euthanasia” in Germany c. 1900-1945, Nueva York, Cambridge University Press.Burleigh, Michael y Wolfgang Wippermann. 1996. The Racial State: Germany, 1933-1945, Nueva York, Cambridge University Press.Carol, Anne. 1995. Histoire de l´eugénisme en France: Les médecins et la procréation, XIX-XXe siècles, París, Editions du Seuil.Carrel, Alexis. 1936. “The Mystery of Death”, en Galdston, Iago (comp.), Medicine and Mankind, Nueva York, D-Appleton-Century Company.Carrel, Alexis. 1944. La Prière, París, Plon.Carrel, Alexis. 1948. Le Voyage de Lourdes, París, Plon.Carrel, Alexis. 1950. Réflexions sur la conduite de la vie, París, Plon.Carrel, Alexis. 1994(1935). La incógnita del hombre, Barcelona, Iberia.Carson, Eloy Axel. 2001. The Unfit: History of a Bad Idea, Nueva York, Cold Spring Harbor Laboratory Press.Chambers, Robert W. y Joseph T. Durkin (comps.). 1973. Papers of the Alexis Carrel Centennial Conference, Washington DC, Georgetown University Press.Choueiri, Youssef M. 1997. Islamic Fundamentalism, Boston, Twayne Publishers.Clarke, Jackie. 2001. “Engineering a New Order in the 1930s: The Case of Jean Coutrot”, en French Historical Studies, núm. 1.Conan, Eric y Henri Rousso. 1994. Vichy, ce passé qui ne passe pas, París, Fayard.Didier Delorme, Henriette D. 1963. Alexis Carrel, 1873-1944, humaniste chrétien, Prix Nobel, París, Apostolat de la Presse.Dikotter, Frank. 1998. “Race Culture: Recent Perspectives on the History of Eugenics”, en American Historical Review, n.m. 103.Dowbiggin, Ian R. 1997. Keeping America Sane: Psychiatry and Eugenics in the United States and Canada, 1880-1940, Ithaca, Cornell University Press.Drouard, Alain. 1995. Alexis Carrel (1873-1944): De la mémoire à l´histoire, París, L´Harmattan.Duhamel, Georges. 1930 Scènes de la vie future, París, Mercure de France.Durkin, Joseph. 1964. Alexis Carrel on Man and Society, Nueva York, Harper & Row.Edwards, William S. 1974. Alexis Carrel: Visionary Surgeon, Springfield, Charles C. Thomas Publisher.Fosdick, Raymond. 1924. Wanted: An Aristotle, Garden City, Doubleday, Doran & Company.Fosdick, Raymond. 1928 The Old Savage in the New Civilization, Garden City, Doubleday, Doran & Company.Gallagher, Nancy. 1999. Breeding Better Vermonteers: The Eugenics Project in the Green Mountain State, Hanover, University Press of New England.García González, Armando. 1999. En busca de la raza perfecta: eugenesia e higiene en Cuba (1898-1958), Madrid, Consejo Superior de Investigaciones Científicas.
Gillon, Jean-Jacques. 1951. “Les aspects essentiels de l´oeuvre médical d´Alexis Carrel”, en Le concours médical, 11 de octubre.Gunnar Broberg y Nils Roll-Hansen (comps.) 1996. Eugenics and the Welfare State: Sterilization Policy in Denmark, Sweden, Norway, and Finland, East Lansing, Michigan State University Press.Hawkes, Nigel. 2000. “Clones Raises Transplant Hopes”, en The Times, 15 de marzo.Hawkes, Nigel. 2000. “Dolly et les cinq petits cochons”, en www.humanite.presse.fr, 15 de marzo.Herf, Jeffrey. 1991. El modernismo reaccionario: tecnología, cultura y política en Weimar y el Tercer Reich, México, FCE.Herman, Arthur. 1997. La idea de la decadencia en occidente, Santiago de Chile, Andrés Bello.Iatria. 1953. Revista de la Federación de Consorcios de Médicos Católicos de la Argentina, núm. 122.Kevles, Daniel J. 1985. In the Name of Eugenics: Genetics and the Uses of Human Heredity, Nueva York, Knopf.Lawrence, Christopher y George Weisz. 1998. Greater than the Parts: Holism and Biomedicine, 1920-1950, Nueva York, Oxford University Press.Le Vay, David. 1996. Alexis Carrel: The Perfectibility of Man, Rockville, Kabel Publishing.Lecoq, Benoît. 1986. “L´ édition et la science”, en Martin, Henri-Jean, Roger Chartier y Jean-Pierre Vivet, Histoire de l´édition française, vol. 4, París, Promodis.Lelotte, Fernand (comp.). 1953. Convertis du XXe siècle, París, Casterman.Loubet de Bayle, Jean-Marie. 1969. Les inconformistes des années trente, París, Editions du Seuil.Malinin, Theodore I. 1979. Surgery and Life: The Extraordinary Career of Alexis Carrel, Nueva York, Harcourt Brace Jovanovich.Nau, Jean-Yves. 2000. “Le passé encombrant d´Alexis Carrel”, en Le Monde, 18 de agosto. Nies, Betsy L. 2002. Eugenic Fantasies: Racial Ideologes in the Literature and Popular Culture of the 1920s, Nueva York, Routledge.Nye, Robert A. 1993. “The Rise and Fall of the Eugenics Empire: Recent Perspectives on the Impact of Biomedical Thought in Modern Society”, en Historical Journal, núm.36.O´Brien, John A. 1960. Roads to Rome: The Intimate Personal Stories of Converts to the Catholic Faith, Nueva York, MacMillan.Ordover, Nancy. 2003. American Eugenics: Race, Gender, Queer Anatomy an the Science of Nationalism, Minneapolis, University of Minnesota Press.Palena, Héctor. 2004 Gobernar es seleccionar: apuntes sobre eugenesia, Buenos Aires, Jorge Baudino Ediciones.Pauly, Philip J. 1993. “The Eugenics Industry-Growth or Restructuring?”, en Journal of the History of Biology, n.m. 26.Reggiani, Andrés H. 2000. “Los ´años negros´ (1940-1944): memoria e historia del pasado reciente en Francia”, en Taller. Revista de sociedad, política y cultura, núm. 12.Reggiani, Andrés H. 2002. “Alexis Carrel, the Unknown: Eugenics and Population Politics under Vichy”, en French Historical Studies, núm. 2.Reggiani, Andrés H. 2005. “Staging Science, Selling Eugenics: Technical Expertise, Public Opinion and Biopolitics in Alexis CarrelÕs Man the Unknown", en Codgell, Christina y Sue Currell (comps.), Making It Modern: Eugenics and Popular Culture in the 1930s, Philadelphia, American Philosophical Society.Reilly, Philip R. 1991. The Surgical Solution: A History of Involuntary Sterilization in the United States, Baltimore, Johns Hopkins University Press.Rousso, Henri. 1987 Le Syndrome de Vichy, Par.s, Editions du Seuil.Schneider, William. 1990. Quality and Quantity: The Quest for Biological Regeneration in Twentieth-Century France, Nueva York, Cambridge University Press.Selden, Steven y Ashley Montagu. 1999. Inheriting Shame: The Story of Eugenics and Racism in America, Nueva York, Teacher´s College Press.Simon, Catherine. 1993. “Algérie, d´une violence à l´autre”, en Le Monde, 25 de noviembre.Soupault, Robert. 1952. Alexis Carrel, París, Plon.Stepan, Nancy L. 1991. “The Hour of Eugenics”: Race, Gender, and the Nation in Latin America, Ithaca, Cornell University Press.Tucker, William H. 1994. The Science and Politics of Racial Research, Urbana, Illinois, University of Illinois Press.Walther, Rudolf. 2003. “Die seltsamen Lehren des Doktor Carrel”, en Die Zeit, núm. 32.Weindling, Paul. 1989. Health, Race, and German Politics between National Unification and Nazism,Weindling, Paul. 1870-1945, Nueva York, Cambridge University Press.Witowski, Jan. 1979. “Alexis Carrel and the Mysticism of Tissue Culture”, en Medical History, núm. 23.ARCHIVOSArchivos Alexis Carrel (AAC), Georgetown University.Archivos de la Secretaría de Salud Pública
A Critique of Computable General Equilibrium Models for Trade Policy Analysis
No full textThe paper will deal in turn with three sets of modelling issues: the question of 'data'; the 'micro' problem of specifying market behaviour, and the. 'macro' issue of 'closing' the models in aggregate. I will conclude with some suggestions for future research. The basic theme of the paper is this: CGE modelling is essentially a conservative or 'neoclassical' scientific endeavour, and exhibits the strengths and weaknesses of neoclassicism. And as for the recent injection of apparently nonneoclassical imperfect competition or industrial organization (IO) concepts into CGE, though, as an 10 specialist myself I certainly welcome this in principle, I have doubts about the usefulness of the practice.International Relations/Trade,
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Collaborative Research: Simulation of Beam-Electron Cloud Interactions in Circular Accelerators Using Plasma Models
No full textFinal Report for grant DE-FG02-06ER54888, "Simulation of Beam-Electron Cloud Interactions in Circular Accelerators Using Plasma Models" Viktor K. Decyk, University of California, Los Angeles Los Angeles, CA 90095-1547 The primary goal of this collaborative proposal was to modify the code QuickPIC and apply it to study the long-time stability of beam propagation in low density electron clouds present in circular accelerators. The UCLA contribution to this collaborative proposal was in supporting the development of the pipelining scheme for the QuickPIC code, which extended the parallel scaling of this code by two orders of magnitude. The USC work was as described here the PhD research for Ms. Bing Feng, lead author in reference 2 below, who performed the research at USC under the guidance of the PI Tom Katsouleas and the collaboration of Dr. Decyk The QuickPIC code [1] is a multi-scale Particle-in-Cell (PIC) code. The outer 3D code contains a beam which propagates through a long region of plasma and evolves slowly. The plasma response to this beam is modeled by slices of a 2D plasma code. This plasma response then is fed back to the beam code, and the process repeats. The pipelining is based on the observation that once the beam has passed a 2D slice, its response can be fed back to the beam immediately without waiting for the beam to pass all the other slices. Thus independent blocks of 2D slices from different time steps can be running simultaneously. The major difficulty was when particles at the edges needed to communicate with other blocks. Two versions of the pipelining scheme were developed, for the the full quasi-static code and the other for the basic quasi-static code used by this e-cloud proposal. Details of the pipelining scheme were published in [2]. The new version of QuickPIC was able to run with more than 1,000 processors, and was successfully applied in modeling e-clouds by our collaborators in this proposal [3-8]. Jean-Luc Vay at Lawrence Berkeley National Lab later implemented a similar basic quasistatic scheme including pipelining in the code WARP [9] and found good to very good quantitative agreement between the two codes in modeling e-clouds. References [1] C. Huang, V. K. Decyk, C. Ren, M. Zhou, W. Lu, W. B. Mori, J. H. Cooley, T. M. Antonsen, Jr., and T. Katsouleas, "QUICKPIC: A highly efficient particle-in-cell code for modeling wakefield acceleration in plasmas," J. Computational Phys. 217, 658 (2006). [2] B. Feng, C. Huang, V. K. Decyk, W. B. Mori, P. Muggli, and T. Katsouleas, "Enhancing parallel quasi-static particle-in-cell simulations with a pipelining algorithm," J. Computational Phys, 228, 5430 (2009). [3] C. Huang, V. K. Decyk, M. Zhou, W. Lu, W. B. Mori, J. H. Cooley, T. M. Antonsen, Jr., and B. Feng, T. Katsouleas, J. Vieira, and L. O. Silva, "QUICKPIC: A highly efficient fully parallelized PIC code for plasma-based acceleration," Proc. of the SciDAC 2006 Conf., Denver, Colorado, June, 2006 [Journal of Physics: Conference Series, W. M. Tang, Editor, vol. 46, Institute of Physics, Bristol and Philadelphia, 2006], p. 190. [4] B. Feng, C. Huang, V. Decyk, W. B. Mori, T. Katsouleas, P. Muggli, "Enhancing Plasma Wakefield and E-cloud Simulation Performance Using a Pipelining Algorithm," Proc. 12th Workshop on Advanced Accelerator Concepts, Lake Geneva, WI, July, 2006, p. 201 [AIP Conf. Proceedings, vol. 877, Melville, NY, 2006]. [5] B. Feng, P. Muggli, T. Katsouleas, V. Decyk, C. Huang, and W. Mori, "Long Time Electron Cloud Instability Simulation Using QuickPIC with Pipelining Algorithm," Proc. of the 2007 Particle Accelerator Conference, Albuquerque, NM, June, 2007, p. 3615. [6] B. Feng, C. Huang, V. Decyk, W. B. Mori, G. H. Hoffstaetter, P. Muggli, T. Katsouleas, "Simulation of Electron Cloud Effects on Electron Beam at ERL with Pipelined QuickPIC," Proc. 13th Workshop on Advanced Accelerator Concepts, Santa Cruz, CA, July-August, 2008, p. 340 [AIP Conf. Proceedings, vol. 1086, Melville, NY, 2008]. [7] B. Feng, C. Huang, V. K. Decyk, W. B. Mori, P. Muggli, and T. Katsouleas, "Enhancing parallel quasi-static particle-in-cell simulations with a pipelining algorithm," J. Computational Phys, 228, 5430 (2009). [8] C. Huang, W. An, V. K. Decyk, W. Lu, W. B. Mori, F. S. Tsung, M. Tzoufras, S. Morshed, T. Antonsen, B. Feng, T. Katsouleas, R., A. Fonseca, S. F. Martins, J. Vieira, L. O. Silva, E. Esarey, C. G. R. Geddes, W. P. Leemans, E. Cormier-Michel, J.-L. Vay, D. L. Bruhwiler, B. Cowan, J. R. Cary, and K. Paul, "Recent results and future challenges for large scale particleion- cell simulations of plasma-based accelerator concepts," Proc. of the SciDAC 2009 Conf., San Diego, CA, June, 2009 [Journal of Physics: Conference Series, vol. 180, Institute of Physics, Bristol and Philadelphia, 2009], p. 012005. [9] J.-L. Vay, C. M. Celata, M. A. Furman, G. Penn, M. Venturini, D. P. Grote, and K. G. Sonnad, ?Update on Electron-Cloud Simulations Using the Package WARP-POSINST.? Proc. of the 2009 Particle Accelerator Conference PAC09, Vancouver, Canada, June, 2009, paper FR5RFP078
Observations of convective and dynamical instabilities in tropopause folds and their contribution to stratosphere-troposphere exchange
No full textWith aircraft-mounted in situ and remote sensing instruments for dynamical, thermal, and chemical measurements we studied two cases of tropopause folding. In both folds we found Kelvin-Helmholtz billows with horizontal wavelength of ∼900 m and thickness of ∼120 m. In one case the instability was effectively mixing the bottomside of the fold, leading to the transfer of stratospheric air into the troposphere. Also, we discovered in both cases small-scale secondary ozone maxima shortly after the aircraft ascended past the topside of the fold that corresponded to regions of convective instability. We interpreted this phenomenon as convectively breaking gravity waves. Therefore we posit that convectively breaking gravity waves acting on tropopause folds must be added to the list of important irreversible mixing mechanisms leading to stratosphere-troposphere exchange.The work at MIT was funded by NASA grants NAG2-1105, NAGl-1758, and NAGl-1901.The work performed by M. J. Mahoney was carried out by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. He also acknowledges the able assistance of Bruce L. Gary with the MTP data analysis. Finally, we would like to thank the DC-8 flight crew for their hard work.https://onlinelibrary.wiley.com/doi/abs/10.1029/1999JD90043
Protein and energy nutrition of marine gadoids, Atlantic cod (Gadus morhua L.) and haddock (Melanogrammus aeglefinus L.)
No full text Primary goals of this thesis were to: 1) examine the in vivo digestion of macronutrients from conventional or alternative feed ingredients used in practical diets of juvenile gadoids (Atlantic cod and haddock), 2) document growth potential of fish at the juvenile grower phase given varying levels of dietary protein and energy and 3) assess the potential of in vitro pH-Stat methods for rapid screening protein quality of feed ingredients, specifically for gadoids. All primary research questions were linked to and built upon one another with the goal of gaining a better understanding of protein and energy utilization of juvenile grower phase gadoids. Studies showed that cod and haddock have a high capacity to utilize a wide range of dietary feed ingredients, such as fish meals, zooplankton meal, soybean products (meal, concentrate and isolate) and wheat gluten meal. New dietary formulations for gadoids may also utilize pulse meals, corn gluten meal, canola protein concentrate and crab meal. Digestibility data in this thesis is currently the only research that examined both in vivo and in vitro macronutrient digestibility of a large number and wide range of individual ingredients, specifically for gadoids. This is essential to gain new knowledge on protein and energy utilization as well as for least-cost ration formulations and effective substitution of ingredients into new formulations. Data has demonstrated a dietary digestible protein/digestible energy (DP/DE)ratio of 30 g DP/MJ DE is required for gadoids during the juvenile phase (in vitro closed-system pH-Stat assay for rapid screening protein quality of test ingredients that is ‘species-specific’ to gadoids. It is demonstrated that in vitro results generally reflected results obtained through conventional in vivo protein digestibility methods. Studies resulted in the first generation of a ‘gadoid-specific’ proteolytic enzyme extraction method and in vitro closed-system pH-Stat assay which may be useful to investigate protein digestion, absorption and metabolism of gadoids and further development of their feeds. </p
