Search Results - (Author, Cooperation:J. Elser)
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1Latest Papers from Table of Contents or Articles in PressA. J. Cease ; J. J. Elser ; C. F. Ford ; S. Hao ; L. Kang ; J. F. Harrison
American Association for the Advancement of Science (AAAS)
Published 2012Staff ViewPublication Date: 2012-01-28Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyComputer ScienceMedicineNatural Sciences in GeneralPhysicsKeywords: Animal Husbandry ; Animals ; Biomass ; Diet ; Dietary Proteins/administration & dosage ; *Ecosystem ; Feeding Behavior ; Fertilizers ; Food Preferences ; Grasshoppers/growth & development/*physiology ; Herbivory/physiology ; *Livestock ; Nitrogen/*analysis ; Plant Proteins/*analysis ; Plants/*chemistry ; Poaceae/chemistry/growth & development ; Population Dynamics ; SheepPublished by: -
2Latest Papers from Table of Contents or Articles in PressStaff View
Publication Date: 2011-10-08Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsKeywords: Agriculture/economics/methods ; Animals ; Ecosystem ; Environmental Pollutants/analysis/economics/metabolism ; Feces/chemistry ; Fertilizers/economics/supply & distribution ; Food Supply ; Geologic Sediments/chemistry ; Humans ; Phosphorus/*analysis/economics/metabolism/*supply & distribution ; *Recycling/methods/trends ; Waste Management/methods ; Water Supply/analysisPublished by: -
3Latest Papers from Table of Contents or Articles in PressA. A. Myburg ; D. Grattapaglia ; G. A. Tuskan ; U. Hellsten ; R. D. Hayes ; J. Grimwood ; J. Jenkins ; E. Lindquist ; H. Tice ; D. Bauer ; D. M. Goodstein ; I. Dubchak ; A. Poliakov ; E. Mizrachi ; A. R. Kullan ; S. G. Hussey ; D. Pinard ; K. van der Merwe ; P. Singh ; I. van Jaarsveld ; O. B. Silva-Junior ; R. C. Togawa ; M. R. Pappas ; D. A. Faria ; C. P. Sansaloni ; C. D. Petroli ; X. Yang ; P. Ranjan ; T. J. Tschaplinski ; C. Y. Ye ; T. Li ; L. Sterck ; K. Vanneste ; F. Murat ; M. Soler ; H. S. Clemente ; N. Saidi ; H. Cassan-Wang ; C. Dunand ; C. A. Hefer ; E. Bornberg-Bauer ; A. R. Kersting ; K. Vining ; V. Amarasinghe ; M. Ranik ; S. Naithani ; J. Elser ; A. E. Boyd ; A. Liston ; J. W. Spatafora ; P. Dharmwardhana ; R. Raja ; C. Sullivan ; E. Romanel ; M. Alves-Ferreira ; C. Kulheim ; W. Foley ; V. Carocha ; J. Paiva ; D. Kudrna ; S. H. Brommonschenkel ; G. Pasquali ; M. Byrne ; P. Rigault ; J. Tibbits ; A. Spokevicius ; R. C. Jones ; D. A. Steane ; R. E. Vaillancourt ; B. M. Potts ; F. Joubert ; K. Barry ; G. J. Pappas ; S. H. Strauss ; P. Jaiswal ; J. Grima-Pettenati ; J. Salse ; Y. Van de Peer ; D. S. Rokhsar ; J. Schmutz
Nature Publishing Group (NPG)
Published 2014Staff ViewPublication Date: 2014-06-12Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsKeywords: Eucalyptus/classification/*genetics ; Evolution, Molecular ; Genetic Variation ; *Genome, Plant ; Inbreeding ; PhylogenyPublished by: -
4Latest Papers from Table of Contents or Articles in PressStaff View
Publication Date: 2011-12-17Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyComputer ScienceMedicineNatural Sciences in GeneralPhysicsKeywords: *Air Pollutants ; Atmosphere/*chemistry ; Nitrates/*analysis ; Nitrogen/*analysis ; *Nitrogen Cycle ; Seawater/*chemistry ; *Trees ; *Tropical ClimatePublished by: -
5Articles: DFG German National LicensesStaff View
ISSN: 1365-2214Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicinePsychologyNotes: Summary Improvements in therapy have resulted in increasing numbers of children being successfully treated for cancer. However, the aggressiveness of therapy and uncertainty about prognosis are associated with many adverse effects, psychological as well as physical, for both the child and family. This study investigates family coping with treatment in relation to attributions about cause and responsibility for onset of the disease. We interviewed parents of 30 children with cancer (28 mothers and 23 fathers) about their attributions of causality, and perceptions of responsibility for the diagnosis and care of the child. Coping strategies which were found to be helpful were assessed using the Coping Health Inventory for Parents (CHIP). Fathers were more likely than mothers to accept that there was no known cause for the child's illness. Fathers who blamed doctors for failing to diagnose the condition found medical staff less helpful up to 2 years later. The theoretical importance of blaming others more than oneself is discussed, along with practical implications for services In paediatric oncology.Type of Medium: Electronic ResourceURL: -
6Articles: DFG German National LicensesANDRÉSSON, Ó. S. ; ELSER, J. E. ; GEORGSSON, G. ; TOBIN, G. J. ; GREENWOOD, J. D. ; GONDA, M. A. ; ANDRÉSDÓTTIR, V. ; PÁLSSON, P. A. ; PÉTURSSON, G.
Oxford, UK : Blackwell Publishing Ltd
Published 1994Staff ViewISSN: 1749-6632Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Natural Sciences in GeneralType of Medium: Electronic ResourceURL: -
7Articles: DFG German National LicensesStaff View
ISSN: 1432-1793Source: Springer Online Journal Archives 1860-2000Topics: BiologyNotes: Abstract Whole-body carbon (C), nitrogen (N) and phosphorus (P) content, and stable-isotope composition (13C:12C and 15N:14N), were followed during metamorphosis of bonefish (Albula sp.) larvae (leptocephali). Metamorphosing larvae depend entirely on endogenous carbon compounds (some of which contain N and P) as an energy source. Two fundamental questions are (1) Do the demands of extensive tissue remodeling during metamorphosis require the efficient retention of N and P during the catabolism of carbon compounds? (2) What effect does the lack of feeding have on stable-isotope composition? Our results showed that both C and N decreased by ∼35 to 40%, reflecting the utilization of neutral lipid (triacylglycerols) and N-containing compounds (phosphatidylethanolamine and keratan sulfate glycosaminoglycan) as energy sources, and indicating that larvae have little or no capacity to retain N. Evidence suggested that collagen breakdown, measured as a loss of hydroxyproline content, also contributed to N loss. Stable-isotope ratios, expressed as 13C and 15N, showed no statistically significant differences in early and advanced metamorphosing larvae. In contrast to C and N, phosphorus was conserved during metamorphosis and most probably is utilized in the increased bone mineralization occurring in advanced larvae. We show, however, that advanced larvae are P-limited and that normal ossification is dependent upon a supply of exogenous P obtained after the resumption of feeding. The N:P ratio of 12.3 in early larvae decreased to 8.1 in advanced larvae owing to the conservation of P as N was lost. The mean 15N value in early metamorphic larvae (11.6‰) is consistent with results from other studies, and provides further support for the view that premetamorphic leptocephali feed at a very low trophic level.Type of Medium: Electronic ResourceURL: -
8Articles: DFG German National LicensesElser, J. J. ; Chrzanowski, T. H. ; Sterner, R. W. ; Schampel, J. H. ; Foster, D. K.
Springer
Published 1995Staff ViewISSN: 1432-184XSource: Springer Online Journal Archives 1860-2000Topics: BiologyNotes: Abstract The dynamics of carbon (C), nitrogen (N), and phosphorus (P), elemental ratios, and dark uptake/release of N and P in bacterial and phytoplankton size fractions were studied during summer 1992 in three lakes of contrasting food web structure and trophic status (L240, L110, L227). We wished to determine if phytoplankton and bacteria differed in their elemental characteristics and to evaluate whether the functional role of bacteria in nutrient cycling (i.e., as sink or source) depended on bacterial elemental characteristics. Bacterial contributions to total suspended particulate material and to fluxes of nutrients in the dark were substantial and varied for different elements. This indicated that some techniques for assaying phytoplankton physiological condition are compromised by bacterial contributions. C/N ratios were generally less variable than C/P and N/P ratios. Both elemental ratios and biomass-normalized N and P flux indicated that phytoplankton growth in each lake was predominantly P-limited, although in L227 these data reflect the dominance of N-fixing cyanobacteria, and N was likely limiting early in the sampling season. In L227, phytoplankton N/P ratio and biomass-normalized N flux were negatively correlated, indicating that flux data were likely a reasonable measure of the N status of the phytoplankton. However, for L227 phytoplankton, P-flux per unit biomass was a hyperbolic function of N/P, suggesting that the dominant L227 cyanobacteria have a limited uptake and storage capacity and that P-flux per unit biomass may not be a good gauge of the P-limitation status of phytoplankton in this situation. Examination of N-flux data in the bacterial size fraction relative to the N/P ratio of the bacteria revealed a threshold N/P ratio (∼22:1 N/P, by atoms), below which, bacteria took up and sequestered added N, and above which, N was released. Thus, the functional role of bacteria in N cycling in these ecosystems depended on their N/P stoichiometry.Type of Medium: Electronic ResourceURL: -
9Articles: DFG German National LicensesStaff View
ISSN: 1432-184XSource: Springer Online Journal Archives 1860-2000Topics: BiologyNotes: Abstract Bacterial abundance results from predatory losses of individuals and replacement of losses through growth. Growth depends on sustained input of organic substrates and mineral nutrients. In this work we tested the hypothesis that bacterial growth in two oligotrophic Canadian shield lakes was limited by nitrogen (N) or phosphorus (P). We also determined whether consumer-regenerated resources contributed substantially to net bacterial growth. Two types of dilution assays were conducted to determine the response of bacteria to nutrient enrichment: diluted whole water (DWW, 1:9 whole/filtered with 0.2 μm of filtered lake water) and diluted fractionated water (DFW, 1.0 μm prefiltered then diluted as above). Replicate bottles in each dilution assay received either N (50 μm), P (10 μm), or both N and P enrichments. Controls received no nutrients. Resource-saturated growth rates and grazing rates were estimated from a standard dilution-growth approach. Bacterial growth was stimulated by addition of P alone and in combination with N. Consumers regenerated sufficient resources to support up to half the bacterial growth rate, but the benefit derived from consumers was minor when compared to mortality.Type of Medium: Electronic ResourceURL: -
10Articles: DFG German National LicensesDowning, J.A. ; McClain, M. ; Twilley, R. ; Melack, J.M. ; Elser, J. ; Rabalais, N.N. ; Lewis, W.M. ; Turner, R.E. ; Corredor, J. ; Soto, D. ; Yanez-Arancibia, A. ; Kopaska, J.A. ; Howarth, R.W.
Springer
Published 1999Staff ViewISSN: 1573-515XKeywords: estuaries ; lakes ; marine ; nitrogen ; phosphorus ; rivers ; streams ; temperate ; tropicsSource: Springer Online Journal Archives 1860-2000Topics: Chemistry and PharmacologyGeosciencesNotes: Abstract Published data and analyses from temperate and tropical aquatic systems are used to summarize knowledge about the potential impact of land-use alteration on the nitrogen biogeochemistry of tropical aquatic ecosystems, identify important patterns and recommend key needs for research. The tropical N-cycle is traced from pre-disturbance conditions through the phases of disturbance, highlighting major differences between tropical and temperate systems that might influence development strategies in the tropics. Analyses suggest that tropical freshwaters are more frequently N-limited than temperate zones, while tropical marine systems may show more frequent P limitation. These analyses indicate that disturbances to pristine tropical lands will lead to greatly increased primary production in freshwaters and large changes in tropical freshwater communities. Increased freshwater nutrient flux will also lead to an expansion of the high production, N- and light-limited zones around river deltas, a switch from P- to N-limitation in calcareous marine systems, with large changes in the community composition of fragile mangrove and reef systems. Key information gaps are highlighted, including data on mechanisms of nutrient transport and atmospheric deposition in the tropics, nutrient and material retention capacities of tropical impoundments, and N/P coupling and stoichiometric impacts of nutrient supplies on tropical aquatic communities. The current base of biogeochemical data suggests that alterations in the N-cycle will have greater impacts on tropical aquatic ecosystems than those already observed in the temperate zone.Type of Medium: Electronic ResourceURL: -
11Articles: DFG German National LicensesDini, M. L. ; O'Donnell, J. ; Carpenter, S. R. ; Elser, M. M. ; Elser, J. J. ; Bergquist, A. M.
Springer
Published 1987Staff ViewISSN: 1573-5117Keywords: Daphnia ; diel cycle ; excretion ; migration ; phosphorusSource: Springer Online Journal Archives 1860-2000Topics: BiologyNotes: Abstract The timing and magnitude of diel migration in two daphnid assemblages were determined from a series of vertical profiles of daphnid size distribution. Animals were collected concurrently for gut fullness determination. Only large daphnids (〉 1.4 mm) migrated, but these animals could account for substantial vertical and diel differences in phosphorus excretion rate. Gut fullness measurements and time courses of diel vertical migration suggested that large Daphnia can cause a net downward flux of phosphorus during summer in thermally stratified lakes.Type of Medium: Electronic ResourceURL: -
12Articles: DFG German National LicensesDowning, J. A. ; Mcclain, M. ; Twilley, R. ; Melack, J. M. ; Elser, J. ; Rabalais, N. N. ; Lewis, W. M. ; Turner, R. E. ; Corredor, J. ; Soto, D. ; Yanez-Arancibia, A. ; Kopaska, J. A. ; Howarth, R. W.
Springer
Published 1999Staff ViewISSN: 1573-515XKeywords: estuaries ; lakes ; marine ; nitrogen ; phosphorus ; rivers ; streams ; temperate ; tropicsSource: Springer Online Journal Archives 1860-2000Topics: Chemistry and PharmacologyGeosciencesNotes: Abstract Published data and analyses from temperate and tropical aquatic systems are used to summarize knowledge about the potential impact of land-use alteration on the nitrogen biogeochemistry of tropical aquatic ecosystems, identify important patterns and recommend key needs for research. The tropical N-cycle is traced from pre-disturbance conditions through the phases of disturbance, highlighting major differences between tropical and temperate systems that might influence development strategies in the tropics. Analyses suggest that tropical freshwaters are more frequently N-limited than temperate zones, while tropical marine systems may show more frequent P limitation. These analyses indicate that disturbances to pristine tropical lands will lead to greatly increased primary production in freshwaters and large changes in tropical freshwater communities. Increased freshwater nutrient flux will also lead to an expansion of the high production, N- and light-limited zones around river deltas, a switch from P- to N-limitation in calcareous marine systems, with large changes in the community composition of fragile mangrove and reef systems. Key information gaps are highlighted, including data on mechanisms of nutrient transport and atmospheric deposition in the tropics, nutrient and material retention capacities of tropical impoundments, and N/P coupling and stoichiometric impacts of nutrient supplies on tropical aquatic communities. The current base of biogeochemical data suggests that alterations in the N-cycle will have greater impacts on tropical aquatic ecosystems than those already observed in the temperate zone.Type of Medium: Electronic ResourceURL: -
13Articles: DFG German National LicensesStaff View
ISSN: 1573-515XKeywords: chlorophyll ; grazing ; lakes ; paleolimnology ; pheophorbide ; sedimentationSource: Springer Online Journal Archives 1860-2000Topics: Chemistry and PharmacologyGeosciencesNotes: Abstract Budgets for chlorophyll a and selected degradation products were constructed during summer stratification in 1984 and 1985 in two lakes. In Paul Lake, the reference ecosystem, pigment sedimentation showed no significant interannual differences. In Tuesday Lake, fish manipulations in May 1985 changed the zooplankton from an assemblage of Bosmina and small cyclopoids to one of large cladoceran grazers. Sedimentation of pigments, especially the grazing indicator pheophorbide a, increased significantly as the grazer assemblage changed. Mean grazer size was positively related to pheophorbide deposition rate in both lakes. Results of this whole-lake experiment indicate that major changes in lake food webs alter pigment deposition rates.Type of Medium: Electronic ResourceURL: