bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of Models for Describing the Transport of Dissolved Organic Carbon in Aquifer Columns
Authors: Jardine P. M. , Dunnivant F. M. , Selim H. M. , McCarthy J. F. 
Published: July 2010

AbstractDissolved organic carbon (DOC) is a reactive constituent in aquifer and soil media and equilibrates between the mobile aqueous phase and the immobile solid phase. Since DOC is believed to accelerate the transport of associated contaminants, yet is known to interact with aquifer and soil material, our objective was to define and model those processes governing DOC adsorption to porous media that may affect the cotransport of contaminants. Column displacement experiments of DOC through aquifer sediments were modeled with various formulations of the convective‐dispersive equation, which considered time‐dependent adsorption reactions and linear or nonlinear adsorption processes. Batch equilibrium adsorption isotherm and kinetic studies for DOC interaction with the sediments were used to parameterize the transport models. The equilibrium DOC‐adsorption isotherm was nonlinear and was adequately described by the Langmuir equation. The adsorption of DOC to the aquifer sediment was also time dependent and the batch results could be described by two simultaneous reaction rates for solution concentrations ≥ 10 mg DOC L−1 and a single reaction rate for solution concentrations <10 mg DOC L−1. Observed DOC breakthrough curves (BTCs) with influent concentrations ≥ 10 mg DOC L−1, were adequately modeled as two‐site, non‐linear adsorption processes, with DOC interactions with both types of sites being time dependent. Batch adsorption and kinetic parameters were generally successful in describing DOC transport; however, the magnitude of the initial batch rate coefficient was significantly larger than that observed for the displacement experiments. The extended tailing of the observed DOC BTCs was influenced more by the slow, time‐dependent adsorption of DOC during transport than to the non‐linear features of the adsorption isotherms. Observed DOC BTCs with influent concentrations <10 mg DOC L−1 did not exhibit extensive tailing and were modeled as a one‐site, linear or nonlinear, time‐dependent adsorption process.
Organic Carbon Turnover in Three Tropical Soils under Pasture after Deforestation
Authors: Veldkamp E. 
Published: July 2010

AbstractDeforestation is one of the main reasons for the global net release of CO2 from soil to atmosphere. Estimates of CO2 emission from soils are highly variable, mainly due to limited data of C dynamics in soils after forest clearing. The objective of this study was to calculate the changes in soil organic carbon (SOC) storage after deforestation in three soil types in the Atlantic Zone of Costa Rica with help of the δ13C method. Changes in bulk density, which normally accompany land use changes, had a profound influence on the results of the calculations. Deforestation, followed by 25 yr of pasture, caused a net loss of 21.8 Mg ha−1 in SOC for an Eutric Hapludand and 1.5 Mg ha−1 for an Oxic Humitropept. The SOC changes in time were studied on a deforestation sequence on an Andic Humitropept. In the first years after forest clearing, decomposition of tree roots caused an extra input of SOC, which influenced the δ13C signal. Decomposition of forest C and increase of pasture C were mathematically described for several depths. A considerable influence of depth on decomposition rates was found. The strong stabilization of organic C by Al‐organic matter complexes probably caused the relatively small net C loss from SOC since forest clearing.
Residue Management for Winter Wheat and Grain Sorghum Production with Limited Irrigation
Authors: Unger Paul W. 
Published: July 2010

AbstractWinter wheat (Triticum aestivum L.) and grain sorghum [Sorghum bicolor (L.) Moench] are extensively grown in the southern Great Plains on dryland and with irrigation, but yields often are low on dryland and irrigation water is limited. Because both crops respond well to timely irrigation, they sometimes are grown with limited irrigation. Thus, it was hypothesized that using limited irrigation for these crops would produce sufficient residues to increase soil water storage if conservation tillage practices were used. This study on Pullman soil (fine, mixed, thermic Torrertic Paleustoll) at Bushland, TX, determined the effects of residue management on soil water storage and use, yields, and yield components for wheat and sorghum grown in rotation with limited irrigation. Treatments were no‐tillage with standing (T1) or shredded (T2) residues, and no‐tillage after wheat and tillage after sorghum (T3). Tillage did not affect water storage after wheat, but storage ranged from 68 mm with T3 to 101 mm with T1 after sorghum. Water use by wheat ranged from 93 mm with T3 to 131 mm with T1, but tillage did not affect water use by sorghum. Tillage did not affect wheat yields because differences in soil water storage and use were small and irrigations minimized the water content differences. Tillage did not affect sorghum yields because using no‐tillage during fallow after wheat resulted in similar water storage in all cases. This study showed that practices that retain surface residues are effective for producing wheat and grain sorghum in rotation under limited‐irrigation conditions in the southern Great Plains.
Tortuosity, Mean Residence Time, and Deformation of Tritium Breakthroughs from Soil Columns
Authors: Ma L. , Selim H. M. 
Published: July 2010

AbstractTritium breakthrough curves (BTCs) are widely used to estimate the hydrodynamic dispersion coefficient (D) of the convection‐dispersion equation (CDE). However, D alone often provides inadequate fit. Therefore, a second parameter is commonly added to describe tritium BTCs. We tested the validity of describing tritium transport using an effective path length (Le) or a tortuosity factor (τ) in the CDE. We obtained the dimensionless parameter τ from fitted Le and column length L such that τ = L/Le. Miscible displacement experiments were used to obtain tritium BTCs for several soils and materials in uniformly packed columns under water‐saturated and steady upward flow. Two types of tritium pulses were applied: the first was a small pulse (≈ 0.03 pore volume) and used to determine mean residence time (tm) in soil columns. The tm values were obtained from the first time moment of BTCs and were subsequently used to estimate Le and τ. The second type of input pulse was about one pore volume and used to obtain the parameters D and Le using the CDE. Tritium results exhibited double peaks and extensive deformations of BTCs for several soils; these were more distinct with increasing pore water velocity. Using the principle of superposition, bimodal peaks from large pulse inputs were successfully described based on small‐pulse BTCs. In addition, agreements between estimated τ using small pulses and fitted τ from large pulses support the use of the fitting parameters D and Le in the CDE as an alternative method for describing tracer BTCs in soils.
Recently Deposited Organic Matter in Soil Water‐Stable Aggregates
Authors: Angers D. A. , Giroux M. 
Published: July 2010

AbstractSome suggest that young labile soil organic matter accumulates preferentially in water‐stable macroaggregates (>250 µm) where it acts as a transient binding agent. We determined the proportions of recently deposited C (<15 yr) in water‐stable aggregate size fractions using 13C natural abundance. The experiment was performed on a silty loam (fine‐loamy, mixed, frigid Aeric Haplaquept) on plots that were under either continuous corn (C4) or a mixed C4‐C3 rotation for 15 yr and that had previously been under a permanent meadow (C3). Field‐sieved (6 mm) air‐dry soil samples (0‐10 cm) were either dry sieved or wet sieved with slaking to obtain a range of aggregate sizes. Total organic C contents and natural 13C abundances were determined in each aggregate size fraction, which allowed calculation of the proportions of aggregate C derived from either C3 or C4 (recently deposited C). The proportion of water‐stable macroaggregates in the meadow soil and their C3‐derived C contents decreased with corn cropping. The net loss of C3‐derived C was greater for larger macroaggregates (>2 mm) than for smaller ones. Assuming first‐order kinetics, the estimated half‐life of the C3‐derived C of stable aggregates >2 mm was 13 yr, which corresponds to that reported for macro organic matter in similar systems. Analysis of water‐stable macroaggregates under corn showed that they were enriched in recently deposited C relative to microaggregates and to the whole soil, which partly compensated for their loss in C3‐C. On average, 20% of the C in water‐stable aggregates >1 mm was derived from corn whereas this value was down to 9% in the whole soil and 1% in the microaggregates. The results of this study provide further quantitative evidence that slaking‐resistant macroaggregates are enriched in, and probably stabilized by, recently deposited organic matter.
Changes in Sorption of Imidacloprid with Incubation Time
Authors: Cox Lucía , Koskinen William C. , Yen Pau Yong 
Published: July 2010

AbstractChanges in sorption of the insecticide imidacloprid (1‐[(6‐chloro‐3‐pyridinyl)‐methyl]‐N‐nitro‐2‐imidazolidinimine) with aging in three soils have been determined. Soil moisture was adjusted to −33 kPa and 14C‐ and analytical‐grade imidacloprid added to the soil at a rate of 1.0 mg kg−1. Imidacloprid‐spiked soils were incubated at 25°C for 16 wk. Replicate soil samples were periodically extracted successively with 0.01 M CaCl2, acetonitrile, and 1 M HCI. Sorption, as indicated by the sorption coefficient (Kd) values, was highest in the soil with highest organic C content, and increased by an average factor of 2.8 in the three soils during the incubation period. This increase was the result of a decrease in the imidacloprid extractable with CaCl2 (solution phase) and the increase in the amount of imidacloprid extractable with acetonitrile and HCI (sorbed phase) with incubation time. It is not known whether the increase in sorption was the result of imidacloprid diffusion to less accessible or stronger binding sites with time, a rate of degradation in solution and on labile sites that is faster than the rate of desorption, or a combination of the two processes. These results are, however, further evidence that increases in sorption during pesticide aging should be taken into account during characterization of the sorption process for mathematical models of pesticide leaching.
Tâche, progression, curriculum
Authors: Coste Daniel 
Published: July 2010

Résumé Le Cadre européen commun de référence (CECR) propose un modèle d'ensemble où le rapport entre « stratégie », « texte » et « tâche » occupe une position centrale et en quelque sorte motrice. C'est dans cette perspective, dite « actionnelle » que la notion de tâche trouve à s'inscrire, ni comme seulement « communicationnelle » ni comme d'abord scolaire. La question posée est celle des rapports entre tâches, progressions et curriculums.
A reconnaissance of tropical resources during Revolutionary years: the role of the Paris Museum d'Histoire Naturelle
Authors: LY-TIO-FANE MADELEINE 
Published: July 2010

SUMMARYThe recent extensive literature on exploration and the resulting scientific advances has failed to highlight the contribution of Austrian enterprise to the study of natural history. The leading role of Joseph II among the neutral powers which assumed the carrying trade of the belligerents during the American War of Independence, furthered the development of collections for the Schönbrunn Park and Gardens which had been set up on scientific principles by his parents. On the conclusion of peace, Joseph entrusted to Professor Maerter a world-encompassing mission in the course of which the Chief Gardener Franz Boos and his assistant Georg Scholl travelled to South Africa to collect plants and animals. Boos pursued the mission to Isle de France and Bourbon (Mauritius and Reunion), conveyed by the then unknown Nicolas Baudin. He worked at the Jardin du Roi, Pamplemousses, with Nicolas Cere, or at Palma with Joseph Francois Charpentier de Cossigny. The linkage of Austrian and French horticultural expertise created a situation fraught with opportunities which were to lead Baudin to the forefront of exploration and scientific research as the century closed in the upheaval of the Revolutionary Wars.
Insect collections made by Captain P.P. King in South America 1826–1830, with a list of some of the beetles
Authors: THOMPSON RICHARD T. 
Published: July 2010

Some of the insects collected by Captain P.P. King during his survey of the Straits of Magellan, 1826–30, have been studied and published on but several major groups were sold at auction and dispersed without being studied. The purpose of this paper is to draw attention to the fact that King's South American insects bear characteristic labels by which they may be recognized. The dispersal of King's insects is documented and a list given of some beetles that have not previously been studied.
Charles Plumier (1646–1704) and his drawings of French and American fishes
Authors: PIETSCH THEODORE W. 
Published: July 2010

ABSTRACT: The ichthyological drawings of the French Minim friar Charles Plumier (1646–1704), resulting from his explorations along the coasts of Languedoc and Provence, in the French Alps, on the islands of Hyères, and during three expeditions to the West Indies between 1689 and 1697, are described, identified, and catalogued. A sketch of Plumier's life is given, along with an account of his publications and surviving manuscripts, a discussion of the sources for his knowledge of fishes, and the uses made of his fish drawings.
Antitumor Effect after Radiofrequency Ablation of Murine Hepatoma Is Augmented by an Active Variant of CC Chemokine Ligand 3/Macrophage Inflammatory Protein-1α
Authors: Iida Noriho , Nakamoto Yasunari , Baba Tomohisa , Nakagawa Hidetoshi , Mizukoshi Eishiro , Naito Makoto , Mukaida Naofumi , Kaneko Shuichi 
Published: July 2010

AbstractSeveral chemokines are used for immunotherapy against cancers because they can attract immune cells such as dendritic and cytotoxic T cells to augment immune responses. Radiofrequency ablation (RFA) is used to locally eliminate cancers such as hepatocellular carcinoma (HCC), renal cell carcinoma, and lung cancer. Because HCC often recurs even after an eradicative treatment with RFA, additional immunotherapy is necessary. We treated tumor-bearing mice by administering ECI301, an active variant of CC chemokine ligand 3, after RFA. Mice were injected s.c. with BNL 1ME A.7R.1, a murine hepatoma cell line, in the bilateral flank. After the tumor became palpable, RFA was done on the tumor of one flank with or without ECI301. RFA alone eliminated the treated ipsilateral tumors and retarded the growth of contralateral non–RFA-treated tumors accompanied by massive T-cell infiltration. Injection of ECI301 augmented RFA-induced antitumor effect against non–RFA-treated tumors when administered to wild-type or CCR5-deficient but not CCR1-deficient mice. ECI301 also increased CCR1-expressing CD11c+ cells in peripheral blood and RFA-treated tumors after RFA. Deficiency of CCR1 impairs accumulation of CD11c+, CD4+, and CD8+ cells in RFA-treated tumors. Furthermore, in IFN-γ-enzyme-linked immunospot assay, ECI301 augmented tumor-specific responses after RFA whereas deficiency of CCR1 abolished this augmentation. Thus, we proved that ECI301 further augments RFA-induced antitumor immune responses in a CCR1-dependent manner. Cancer Res; 70(16); 6556–65. ©2010 AACR.
Genome-Wide Identification of PAX3-FKHR Binding Sites in Rhabdomyosarcoma Reveals Candidate Target Genes Important for Development and Cancer
Authors: Cao Liang , Yu Yunkai , Bilke Sven , Walker Robert L. , Mayeenuddin Linnia H. , Azorsa David O. , Yang Fan , Pineda Marbin , Helman Lee J. , Meltzer Paul S. 
Published: July 2010

Abstract
The PAX3-FKHR fusion protein is present in a majority of alveolar rhabdomyosarcomas associated with increased aggressiveness and poor prognosis. To better understand the molecular pathogenesis of PAX3-FKHR, we carried out the first, unbiased genome-wide identification of PAX3-FKHR binding sites and associated target genes in alveolar rhabdomyosarcoma. The data shows that PAX3-FKHR binds to the same sites as PAX3 at both MYF5 and MYOD enhancers. The genome-wide analysis reveals that the PAX3-FKHR sites are (a) mostly distal to transcription start sites, (b) conserved, (c) enriched for PAX3 motifs, and (d) strongly associated with genes overexpressed in PAX3-FKHR–positive rhabdomyosarcoma cells and tumors. There is little evidence in our data set for PAX3-FKHR binding at the promoter sequences. The genome-wide analysis further illustrates a strong association between PAX3 and E-box motifs in these binding sites, suggestive of a common coregulation for many target genes. We also provide the first direct evidence that FGFR4 and IGF1R are the targets for PAX3-FKHR. The map of PAX3-FKHR binding sites provides a framework for understanding the pathogenic roles of PAX3-FKHR, as well as its molecular targets to allow a systematic evaluation of agents against this aggressive rhabdomyosarcoma. Cancer Res; 70(16); 6497–508. ©2010 AACR.
Influence of Soil Moisture Levels and Seasonal Weather on Efficiency of Water Use by Corn1
Authors: Letey J. , Peters D. B. 
Published: July 2010

SynopsisCorn yields were closely related to the reserve soil moisture conditions at the beginning of the growing season and to the soil moisture stress to which the plant is subjected during the growing season. The moisture stress effect upon growth was found to be closely related to seasonal weather. The efficiency of water use was found to be strongly conditioned by soil temperature.
Principles of Nutrient Uptake From Fertilizer Bands II. Root Development in the Band1
Authors: Duncan W. G. , Ohlrogge A. J. 
Published: July 2010

SynopsisGrowth stimulation of that part of the root system of a young corn plant in soil fertilized with both nitrogen and phosphorus was not produced by nitrogen fertilizer alone and to only a limited degree by phosphorus fertilizer alone. The greater growth was due to rapid development and branching of the smaller roots. Distribution of roots was not influenced by salt concentration within wide limits. Uptake of phosphorus was closely correlated with root development and volume of fertilized soil.
The Effect of Season, Plant Maturity, and Height on the Tannin Content of Sericea Lespedeza, L. cuneata1
Authors: Donnelly E. D. 
Published: July 2010

SynopsisTannin in sericea aftermaths increased as the season advanced. Tannin content increased concurrently with a rise in temperature and a decrease in rainfall. Tannin content increased with maturity. Plant height was not associated with tannin content.
Iron Absorption by Roots as Affected by Plant Species and Concentration of Chelating Agent
Authors: Brown J. C. , Tiffin L. O. , Specht A. W. , Resnicky J. W. 
Published: July 2010

SynopsisIncreasing the concentration of chelating agent in a nutrient medium decreased the capacity of roots to absorb Fe. Of 11 plant species tested, growth was impeded sharply in 6 species when the molar concentration of chelating agent exceeded that of Fe. Other plant species absorbed Fe at higher chelating agent concentrations. Plant species differed also in their capacity to absorb Fe relative to Cu and Mn.
Photosynthesis Rates of Young Rice Plants as Affected by Light Intensity and Temperature1
Authors: Ormrod D. P. 
Published: July 2010

SynopsisRice seedlings maintain an appreciable net photosynthesis rate at low temperature (40 or 60° F.) and a wide range of light intensities. Low light intensities at a higher temperature (80° F.) result in net losses of CO2 from the plants. Respiration losses increase with increasing temperature, and the light intensity required at the compensation point increases with increasing temperature.
Accelerated Wear Tests on Turfgrasses1
Authors: Youngner Victor. B. 
Published: July 2010

SynopsisZoysia, bermuda grasses and tall fescue were the most wear resistant turfgrass varieties. Sunturf and U‐3 were the most resistant bermudagrass varieties. Grasses were less resistant to wear from spiked rollers than from scuffing feet. Stoloniferous warm‐season grasses recovered more rapidly than cool‐season grasses. Recovery of bermudagrasses was slower from injury from spiked wear elements than from scuffing feet.
Ammonia Losses from Fertilized Nebraska Soils1
Authors: Meyer R. D. , Olson R. A. , Rhoades H. F. 
Published: July 2010

SynopsisField experiments with different crops in Nebraska often have shown a low efficiency of surface applied N fertilizer, especially when broadcasting was done in the fall. As partial explanation, laboratory and greenhouse studies of this problem showed substantial ammonia evolution from fertilized soil particularly with neutral to alkaline soil reaction, with surface application of the fertilizer and with limited moisture. Losses were greatest with urea and urea‐containing materials among the N salts studied. A surface residue accentuated ammonia volatilization, especially with N solution containing urea.
Deep Tillage Effects on Soils and Crops
Authors: Hobbs J. A. , Herring R. B. , Peaslee D. E. , Harris W. W. , Fairbanks G. E. 
Published: July 2010

SynopsisDeep tillage lowered bulk density and improved permeability in the dense layers. When subsequent tillage erased the chisel or subsoiler marks, deep tillage did not improve moisture movement into the soils nor did it increase moisture storage. Crop yields seldom were increased by deep tillage. Deep placement of fertilizer did not prove superior to surface applications in most instances. In no case did deep tillage or deep fertilizer placement increase the profit from crop production.
Crop Experiments on the Effect of 2‐Chloro‐6‐(Trichloromethyl)Pyridine for the Control of Nitrification of Ammonium and Urea Fertilizers1
Authors: Swezey A. W. , Turner G. O. 
Published: July 2010

SynopsisGrowth and yield increases were obtained in cotton, corn, and sugar beets with the treated fertilizers as compared to equal rates of untreated fertilizers. These growth increases are considered to have been due to the inhibition of nitrification by the chemical additive, and subsequent reduction in nitrogen losses by leaching.
Calcium‐Boron Nutrition as Related to Concealed Damage in Peanuts1
Authors: Cox F. R. , Reid P. H. 
Published: July 2010

SynopsisNutritional factors affecting concealed‐damage in peanuts were studied in field experiments. Two forms of physiological damage were noted, one causing discoloration of the cotyledon and the other causing discoloration of the plumule. The amount of each form was decreased by applications of boron and/or calcium. The application of boron was more effective than calcium in reducing the percentage cotyledon damage whereas the application of calcium was more effective than boron in reducing the percentage plumule damage.
Effects of Temperature and Daylength on the Development of Lignin, Cellulose, and Protein in Dactylis glomerata L. and Bromus inermis Leyss1
Authors: Bowman Dale E. , Law Alvin G. 
Published: July 2010

SynopsisPercent lignin was negatively correlated with temperature for Latar orchardgrass but not for Manchar smooth bromegrass. Percent lignin showed no correlation with daylength for either grass. Protein percent showed a significant negative correlation with daylength. Total leaf production was highest for both grasses at 85° F. or under the 14‐hour daylength.