802 research outputs found
Nutrient and biogenic particulate distributions, primary productivity and nitrogen uptake in the Weddell-Scotia Sea marginal ice zone during winter
During austral winter of 1988, we determined the distributions of inorganic nutrients (nitrate, silicic acid, phosphate, nitrite and ammonium) and particulate materials (chlorophyll, biogenic silica, particulate organic carbon and particulate organic nitrogen), as well as primary productivity and rates of nutrient (NO3ā and NH4+) uptake in the upper 150 m of the marginal ice zone of the Weddell-Scotia Sea. Nutrient concentrations were high and particulate matter levels were low throughout the study area, but occasionally nutrient minima and particulate maxima occurred near the ice edge associated with warm-core eddies. Chlorophyll concentrations and primary productivity averaged 0.12 Ī¼g lā1 and 32 mg C mā2 dā1, respectively. Surface growth rates calculated from carbon uptake and total particulate organic carbon were very low (ca. 0.03 doublings dā1), but living phytoplankton only comprised about 10% of the POC in the surface layer. Thus, mean phytoplankton growth rates appear to have been between 0.1 and 0.2 doublings dā1. Although nitrate was about 40 times as abundant as ammonium, ammonium was consistently the preferred substrate of the plankton assemblages, accounting for over half of the nitrogen taken up. Paired samples from the same depth and vertically integrated f-ratios averaged 0.43. Both ammonium and nitrate were removed at rates that individually exceeded the apparent nitrogen demand of the phytoplankton, implying significant heterotrophic uptake of inorganic nitrogen
A novel class of CoA-transferase involved in short-chain fatty acid metabolism in butyrate-producing human colonic bacteria
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Chemical data from Oregon waters, 1972
This report presents data collected on six cruises made during the months May-October 1972 along the Oregon coast. Both complete data listings and sequential surface data contour charts are presented. The latter graphically display rapid changes in surface water characĀteristics on time scales as short as a few hours.
The data were gathered concurrently with CUEA data previously published. All chemical data presented herein have been submitted to the National Oceanographic Data Center
Many particle entanglement in two-component Bose-Einstein Condensates
We investigate schemes to dynamically create many particle entangled states
of a two component Bose-Einstein condensate in a very short time proportional
to 1/N where is the number of condensate particles. For small we
compare exact numerical calculations with analytical semiclassical estimates
and find very good agreement for . We also estimate the effect of
decoherence on our scheme, study possible scenarios for measuring the entangled
states, and investigate experimental imperfections.Comment: 12 pages, 8 figure
On the Classical Stability of Orientifold Cosmologies
We analyze the classical stability of string cosmologies driven by the
dynamics of orientifold planes. These models are related to time-dependent
orbifolds, and resolve the orbifold singularities which are otherwise
problematic by introducing orientifold planes. In particular, we show that the
instability discussed by Horowitz and Polchinski for pure orbifold models is
resolved by the presence of the orientifolds. Moreover, we discuss the issue of
stability of the cosmological Cauchy horizon, and we show that it is stable to
small perturbations due to in-falling matter.Comment: 40 pages, 13 figures. Reference and conclusion added. Published
versio
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1961
My Ideal Course, Underwater, U.S.A. (page 1) From the Editor (3) Turf Management Club News (3) Quotes from 1961 Seniors (4) The United States Most Western Owned Golf Course: Armed Forces Golf Course, Guam (5) Turf Majors Participate in Horticultural Show (7) Picture - G.C.S.A Scholarships Awarded to Three Turf Seniors (8) Picture - Stockbridge - Majors in turf Management (9) Opportunity and Education (10) The Most Outstanding Turf Senior for the Year - 1961 (11) How We Prepare Our Greens Before Topdressing (12) An Inexpensive Cure for Weeds and Poa Annua (13) Watering (14) Picture - Honorary Members of the Turf Management Club (16) Picture - Graduates of Winter School for Turf Managers - 1961 (17) Welcome Speech by Narry Sperandio (A-1) Handle with Care by Dr. Ellsworth H. Wheeler (A-2) Current Ideas on Green Construction - Panel Discussion (A-4) Automatic Systems for Watering by Robert F. Harper (A-14) History of Golf Course Architecture by Geoffrey S. Cornish (A-22) Effect of Nutrition on Turf Diseases by Dr. Houston B. Couch Turf Disease Control and Use of Fungicides by Dr. R. J. Lukens Trees and Tree Care by Gordon S. King (A-38) Arsenical Toxicity by Dr. C. R. Skogley (A-41) Soil Reaction to Arsenical Compounds by Joseph E. Steckel Brush Control For the Golf Course by Dr. William I. Boyd (A-51) Massachusetts Highway Herbicide Program by Joseph L. Beasley (A-54) General Turf (Alternate Session): Observations on Highway Turf Establishment & Maintenance by E.F. Button (A-62) Pre-emerge Chemicals for the Control of Crabgrass by Dr. John R. Havis, John M. Zak & Joseph Troll (A-70) Root Growth of Turf Grasses as Affected by Different heights of Cut and Nutrient Levels by Evangel J. Bredakis (A-71) The Use of Sod by Daniel Pellegrino (A-72
The genome sequence of the highly acetic acid-tolerant zygosaccharomyces bailii-derived interspecies hybrid strain ISA1307, isolated from a sparkling wine plant
In this work, it is described the sequencing and annotation of the genome of the yeast strain ISA1307, isolated from a sparkling wine continuous production plant. This strain, formerly considered of the Zygosaccharomyces bailii species, has been used to study Z. bailii physiology, in particular, its extreme tolerance to acetic acid stress at low pH. The analysis of the genome sequence described in this work indicates that strain ISA1307 is an interspecies hybrid between Z. bailii and a closely related species. The genome sequence of ISA1307 is distributed through 154 scaffolds and has a size of around 21.2 Mb, corresponding to 96% of the genome size estimated by flow cytometry. Annotation of ISA1307 genome includes 4385 duplicated genes (~90% of the total number of predicted genes) and 1155 predicted single-copy genes. The functional categories including a higher number of genes are 'Metabolism and generation of energy', 'Protein folding, modification and targeting' and 'Biogenesis of cellular components'. The knowledge of the genome sequence of the ISA1307 strain is expected to contribute to accelerate systems-level understanding of stress resistance mechanisms in Z. bailii and to inspire and guide novel biotechnological applications of this yeast species/strain in fermentation processes, given its high resilience to acidic stress. The availability of the ISA1307 genome sequence also paves the way to a better understanding of the genetic mechanisms underlying the generation and selection of more robust hybrid yeast strains in the stressful environment of wine fermentations.This research was supported by FCT and FEDER through POFC-COMPETE [contracts PEst-OE/EQB/ LA0023/2011_ research line: Systems and Synthetic Biology PTDC/AGR-ALI/102608/2008, PEst-C/BIA/ UI4050/2011, and post-doctoral grant to M.P. (SFRH/BPD/73306/2010) and PhD grants to J.F.G. (SFRH/ BD/80065/2011) and F.C.R. (SFRH/BD/82226/2011)]. U.G. acknowledges the Austrian Science Fund (FWF, special research project F3705)
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