bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transparency and Bidding Competition in International Wheat Trade
Authors: Wilson William W. , Dahl Bruce L. 
Published: July 2005

One of the trade policy issues identified by U.S. interests, including grower groups, traders and policy makers, is price transparency. This has been a point of contention between the United States and Canada as well as other exporting countries with state trading enterprises (STEs). The transparency problem generally refers to the inability to observe terms of trade (including price, quality, credit, etc.)offered by STEs, and the potential strategic advantage this provides in bidding competition. A game theory model of import tendering is developed in this paper to examine the effects of information asymmetry among rivals. Several stylized examples are used to illustrate aspects of competition and to analyze effects on bidding strategies. Results indicate that:

Less uncertainty among rivals reduces equilibrium bids and prices.
Tenders with less transparency have the effect of increasing prices to buyers and payoffs to sellers.
Increases in the number of rivals have the effect of reducing bids and mitigating the informational advantages of STEs.

In all cases, less transparent sellers have an advantage in bidding relative to more transparent sellers. That advantage in our stylized case is in the area of $1–2/t. However, the advantage is reduced when there are many transparent rivals and in the case where transparent players act as agents for an STE.
Evaluating the Effect of Conservation Policies on Agricultural Land Use: A Site‐specific Modeling Approach
Authors: Tanaka Katsuya , Wu JunJie 
Published: July 2005

This study evaluates quantitatively the effect of three policies (payments for cropland retirement, fertilizer use taxes and payments for crop rotations) on agricultural land use in the upper Mississippi River basin. This is done by estimating two logit models of land use decisions using data from the 1982, 1987,1992 and 1997 Natural Resource Inventories. The models predict farmers' crop choice, crop rotation and participation in the Conservation Reserve Program (CRP) at more than 48,000 Natural Resource Inventories sites under each of the three policies. Results suggest that an increase in the CRP rental rates would significantly increase the CRP acreage, but most of the acreage increase would come initially from less fertilizer‐intensive crops. In contrast, a fertilizer use tax would significantly reduce acreage planted to more fertilizer‐intensive crops, and thus would likely be cost effective for reducing agricultural chemical use and pollution. Although an incentive payment for a corn‐soybean rotation would raise acreage of this rotation and reduce the acreage of continuous corn, the acreage response is in general quite inelastic.Cette étude évalue quantitativement les effets rovoqués par les trois politiques (paiements pour le retrait des terres cultivables, taxes sur l'utilisation d'engrais et paiements pour l'alternance des cultures) sur les terres agricoles du bassin supérieur du Mississipi. Ceci est obtenu en évaluant deux modéles logit des décisions sur l'utilisation des terres provenant des données des «Natural Resource Inventories» de 1982, 1987, 1992 et 1997. Les modéles prédisent le choix des cultures des agriculteurs, l'alternance des cultures et la participation du «Conservation Reserve Program (CRP)» dans plus de 48 000 Natural Resource Inventories dans le cadre de chacune des trois politiques. Les résultats suggérent qu'une augmentation des taux de location du CRP accroisse de maniére significative la surface de CRP, mais la majeure partie de cet accroissement de surface provenaient initialement de cultures moins intensives sans engrais. Cependant, l'utilisation d'une taxe sur l'utilisation d'engrais pouvait réduire de maniére significative la surface plantée avec des récoltes intensives utilisant plus d'engrais, et ainsi ce serait sans doute plus économique pour réduire la pollution et l'utilisation de produits chimiques en agriculture. Bien que des paiements incitatifs à l'alternance maïs‐soja réduisent la surface d'une culture continue de maïs et augmentaient la surface de l'alternance maïs‐soja, les résultats aux transformations des surfaces des terres seraient tout à fait rigides.
Design and Costs of a Measurement Protocol for Trades in Soil Carbon Credits
Authors: Mooney Siân , Antle John , Capalbo Susan , Paustian Keith 
Published: July 2005

Previous work has demonstrated that in the absence of transaction costs, contracts that pay producers per carbon (C) credit are more efficient than those that tie payments to changes in management practices. In this paper we develop a measurement protocol to support contracts for C credits and estimate its implementation costs using an empirical example. We find that the costs of implementing a measurement protocol for soil C credits depend on: the price of credits; the regional heterogeneity in C values as well as assumed error and confidence intervals. We find that the upper estimate of measurement costs associated with a contract that pays producers per C credit can be as little as 3% of the value of a credit. These contract measurement costs are less than the efficiency gains from implementing a per‐credit contract.Des travaux antérieurs montrent que si la transaction ne coûte rien, les ententes prévoyant la rémuné ration des agriculteurs par cré dit carbone (C) sont plus efficaces que celles oè les paiements sont lié s à l'adaptation des pratiques culturales. Dans leur article, les auteurs proposent une mé thode de calculpour de telles ententes et estiment ce que coûterait son implantation au moyen d'un exemple empirique. On constate que, pour les cré dits C du sol, le coût de mise en æuvre dépend du prix des cré dits, de l'hé térogénéité régionale de la valeur des crédits ainsi que dxe l'erreur présumée et des intervalles de confiance. On se rend compte que la plus haute estimation du coût des ententes rémunérant les agriculteurs enfonction des crédits C ne dépasse pas trois pour cent de la valeur du crédit. De tels coûts sont inférieurs aux gains de productivité résultant de l'adoption d'une entente articulée sur les crédits C.
Nitrogen Fertilizer Demand from Danish Crop Farms: Regulatory Implications of Heterogeneity
Authors: Hansen Lars Gårn 
Published: July 2005

This paper estimates nitrogen fertilizer demand elasticities for Danish crop farms using the dual profit function approach on micro panel data. The model includes several farm‐specific parameters, allowing us to estimate the mean demand elasticity and test for homogeneity of elasticities across panel farms. The mean own‐price elasticity for nitrogen is −0.45, and there is a significant standard deviation from this mean for individual farms of 0.24.Heterogeneity of demand elasticities implies that regulating fertilizer application through mandated uniform percentage reductions, as is currently used in Danish nitrogen regulation, increases abatement costs relative to tax regulation. Somewhat surprisingly, this causes the abatement costs of quota regulation to be only 8% larger than with tax regulation. Simulation results indicate that the primary threat to the efficiency of uniform reduction schemes comes from inaccurate estimation of baselines rather than from heterogeneity of elasticities.L'auteur estime les élasticités de la demande d'engrais azotés pour l'agriculture danoise en appliquant la fonction du double profit aux données issues de microgroupes de consultation. Le modèle inclut plusieurs paramètres spécifiques à l'agriculture, ce qui permet d'estimer l'élasticité moyenne de la demande et de vérifier l'homogénéité des élasticités pour les agriculteurs consultés. On constate qu'il existe une élasticité‐prix moyenne de −0,45 pour l'azote et que cette moyenne présente un écart‐type significatif de 0,24 par exploitation agricole.Les élasticités hétérogènes de la demande supposent que si on régule les engrais azotés par une réduction uniforme du volume employé en pour cent, ainsi que l'exige présentment le règlement danois, on accroît le coût des mesures de lutte, comparativement à ce qui se produit avec les mesures fiscales. Il est un peu surprenant de voir que la régulation par quota n'augmente le coût des mesures de lutte que de 8%, par rapport aux mesures fiscales. Les résultats de la simulation révèlent que l'efficacité des programmes de réduction uniforme est surtout menacée par une estimation inexacte des valeurs de base et non par l'hétérogénéité des élasticités.
Measuring Real Capital Input in OECD Agriculture
Authors: Ball V. Eldon , Butault Jean‐Pierre , Mesonada Carlos San Juan 
Published: July 2005

This paper provides a farm sector comparison of levels of capital input for 17 OECD countries. The estimates of capital input are derived by representing capital stock as a weighted sum of past investments. The weights correspond to the relative efficiencies of capital goods of different ages, so that the weighted components of capital stock have the same efficiency. We convert estimates of capital stock into estimates of capital services by means of capital rental prices. Comparisons of levels of capital input among countries require data on relative prices of capital input. We obtain relative price levels for capital input among countries via relative investment goods prices, taking into account the flow of capital input per unit of capital stock in each country.Cet article se propose de comparer le niveau du capital dans Vagriculture de 17pays de l'OCDE. Les estimations du niveau de capital sont déduites en calculant un stock de capital comme une somme pondérée des investissements passés. Les poids utilisés correspondent a Vefficacite relative des biens capitaux à différents âges, de telle sorte que les différentes composantes du stock du capital ait la même efficacité. Le stock de capital est déduit une estimation des services de capital en utilisant un taux de rentabilité. Cette comparaison des niveaux de capital entre pays nécessite des données sur les prix relatifs du capital. Ces prix dépendent des prix relatifs des biens capitaux mais aussi des flux de service générés dans chaque pays par une unité de capital.
The Effect of Quality‐Environmental Investment on Horticultural Firms' Competitiveness
Authors: Galdeano‐Gómez Emilio , Céspedes‐Lorente José 
Published: July 2005

The aim of this paper is to analyze the impact that environment‐friendly and management‐quality improvements have on the firm's competitiveness (profitability and market share) within the fresh fruit and vegetable sector. Andalusian farming/marketing entities (producer organizations) serve as a reference for our analysis. For these entities, there are subsidy programs aimed at developing quality and environmental practices. Such programs are a top priority for the CAP's Common Market Organizations. An analysis of a simultaneous equations model is suggested, considering the distinguishing effect of quality‐environmental investment and the possible endogeneity problems among the variables. The results show a positive correlation between the application of the aforementioned activities and the competitiveness of the horticultural firms.L'objectif de ce travail c'est d'analyser l'impact des pratiques de production favorables à l'environnement ainsi que de la gestion de la qualité (rentabilité et part du marché) par rapport aux secteurs des fruits et légumes frais. Les organismes de commercialisation agricole d'Andalousie (organ‐ismes de production) représentent un point de référence pour notre analyse. Ces organismes bénéficient de programs d'aide au développement de la qualité et des pratiques favorables à l'environnement. Ces pro‐grammes constituent une priorité majeure pour les Organisations du Marché Commun dans le cadre des Politiques Agricoles Communes (PAC). Nous proposons ici une analyse d'un modèle aux équations simul‐tanées considérant l'effet caractéristique d'un investissement de qualité de l'environnement ainsi que les possibles problèmes à caractère endogène parmi les variables. Le résultat met en évidence une corrélation positive entre l'application des activités précédemment citées et la compétitivité des entreprises horticoles.
Pentraxin 3 Inhibits Fibroblast Growth Factor 2–Dependent Activation of Smooth Muscle Cells In Vitro and Neointima Formation In Vivo
Authors: Camozzi Maura , Zacchigna Serena , Rusnati Marco , Coltrini Daniela , Ramirez-Correa Genaro , Bottazzi Barbara , Mantovani Alberto , Giacca Mauro , Presta Marco 
Published: July 2005

Objective—The fibroblast growth factor (FGF)/FGF receptor system plays an important role in smooth muscle cell (SMC) activation. Long-pentraxin 3 (PTX3) is a soluble pattern recognition receptor with non-redundant functions in inflammation and innate immunity. PTX3 is produced by different cell types of the vessel wall, including SMCs. PTX3 binds FGF2 and inhibits its angiogenic activity on endothelial cells. We investigated the capacity of PTX3 to affect FGF2-dependent SMC activation in vitro and in vivo.Methods and Results—When added to human coronary artery SMCs, human PTX3 inhibits cell proliferation driven by endogenous FGF2 and the mitogenic and chemotactic activity exerted by exogenous recombinant FGF2. Accordingly, PTX3 prevents125I-FGF2 interaction with FGF receptors on the same cells. Also, PTX3 overexpression after recombinant adeno-associated virus-PTX3gene transfer inhibits human coronary artery SMC proliferation and survival promoted by FGF2 in vitro. Consistently, a single local endovascular injection of recombinant adeno-associated virus-PTX3gene inhibits intimal thickening after balloon injury in rat carotid arteries.Conclusions—PTX3 is a potent inhibitor of the autocrine and paracrine stimulation exerted by FGF2 on SMCs. Local PTX3 upregulation may modulate SMC activation after arterial injury.
Prognostic Implications of Right-Sided Insular Damage, Cardiac Autonomic Derangement, and Arrhythmias After Acute Ischemic Stroke
Authors: Colivicchi Furio , Bassi Andrea , Santini Massimo , Caltagirone Carlo 
Published: July 2005

Background and Purpose—Acute stroke is associated with impairment of cardiac autonomic balance and increased incidence of arrhythmias. These abnormalities appear more relevant in the case of involvement of the right insula in the infarct area. The aim of this study was to assess the impact of right-sided insular damage, cardiac autonomic derangement, and arrhythmias on clinical outcome after acute ischemic stroke.Methods—Holter monitoring for 24 hours was performed in 208 consecutive patients with first-ever acute ischemic stroke. Time- and frequency-domain measures of heart rate variability and arrhythmias were considered in all cases. All patients were followed for a 12-month period after the initial event.Results—During the 12-month follow-up period, 48 patients died (1-year probability of death, 0.23; 95% CI, 0.17 to 0.30). Multivariate analysis demonstrated that age (hazard ratio [HR], 1.06; 95% CI, 1.01 to 1.10;P=0.0087), stroke severity on admission (HR, 1.25; 95% CI, 1.13 to 1.39;P=0.0001), presence of right-sided insular damage (HR, 2.01; 95% CI, 1.13 to 1.39;P=0.0187), as well as lower values of the SD of all normal-to-normal RR intervals (HR, 3.32; 95% CI, 1.67 to 6.24;P=0.002), and presence of nonsustained ventricular tachycardia during Holter monitoring (HR, 2.99; 95% CI, 1.58 to 5.67;P=0.0007) were independent predictors of 1-year mortality.Conclusions—The integration of traditional risk stratifiers with autonomic and arrhythmic markers, and the careful search for right-sided insular involvement, may represent an effective approach for identification of stroke patients at risk for early mortality.
Elimination of human leukemia cells in NOD/SCID mice by WT1-TCR gene–transduced human T cells
Authors: Xue Shao-An , Gao Liquan , Hart Daniel , Gillmore Roopinder , Qasim Waseem , Thrasher Adrian , Apperley Jane , Engels Boris , Uckert Wolfgang , Morris Emma , Stauss Hans 
Published: July 2005

AbstractCytotoxic T lymphocytes (CTLs) specific for an HLA-A2–presented peptide epitope of the Wilms tumor antigen-1 (WT1) can selectively kill immature human leukemia progenitor and stem cells in vitro. In this study we have used retroviral gene transfer to introduce a WT1-specific T-cell receptor (TCR) into T lymphocytes obtained from patients with leukemia and from healthy donors. TCR-transduced T cells kill leukemia cells in vitro and display WT1-specific cytokine production. Intravenous injection of TCR-transduced T cells into nonobese diabetic–severe combined immunodeficiency (NOD/SCID) mice harboring human leukemia cells resulted in leukemia elimination, whereas transfer of control T cells transduced with an irrelevant TCR was ineffective. The data suggest that adoptive immunotherapy with WT1-TCR gene–modified patient T cells should be considered for the treatment of leukemia.
Mitochondrial DNA spectra of single human CD34+ cells, T cells, B cells, and granulocytes
Authors: Ogasawara Yoji , Nakayama Kazutaka , Tarnowka Magdalena , McCoy J. Philip , Kajigaya Sachiko , Levin Barbara C. , Young Neal S. 
Published: July 2005

Abstract
Previously, we described the age-dependent accumulation of mitochondrial DNA (mtDNA) mutations, leading to a high degree of mtDNA heterogeneity among normal marrow and blood CD34+ clones and in granulocytes. We established a method for sequence analysis of single cells. We show marked, distinct mtDNA heterogeneity from corresponding aggregate sequences in isolated cells of 5 healthy adult donors—37.9% ± 3.6% heterogeneity in circulating CD34+ cells, 36.4% ± 14.1% in T cells, 36.0% ± 10.7% in B cells, and 47.7% ± 7.4% in granulocytes. Most heterogeneity was caused by poly-C tract variability; however, base substitutions were also prevalent, as follows: 14.7% ± 5.7% in CD34+ cells, 15.2% ± 9.0% in T cells, 15.4% ± 6.7% in B cells, and 32.3% ± 2.4% in granulocytes. Many poly-C tract length differences and specific point mutations seen in these same donors but assayed 2 years earlier were still present in the new CD34+ samples. Additionally, specific poly-C tract differences and point mutations were frequently shared among cells of the lymphoid and myeloid lineages. Secular stability and lineage sharing of mtDNA sequence variability suggest that mutations arise in the lymphohematopoietic stem cell compartment and that these changes may be used as a natural genetic marker to estimate the number of active stem cells.
Intracellular labile iron pools as direct targets of iron chelators: a fluorescence study of chelator action in living cells
Authors: Glickstein Hava , Ben El Rinat , Shvartsman Maya , Cabantchik Z. Ioav 
Published: July 2005

AbstractThe primary targets of iron chelators used for treating transfusional iron overload are prevention of iron ingress into tissues and its intracellular scavenging. The present study was aimed at elucidating the capacity of clinically important iron chelators such as deferiprone (DFP), desferrioxamine, and ICL670 to (a) gain direct access to intracellular iron pools of key cells of iron accumulation (macrophages, hepatocytes, and cardiomyocyte cell lines); (b) chelate the labile iron present in discrete cell compartments/organelles; and (c) prevent labile iron involvement in the generation of reactive oxidant species. Chelation of cytosolic and organellar cell iron was visualized dynamically and quantitatively in living cells by fluorescence microscopic imaging of fluorescent metallosensors (used as iron-quenched complexes of calceins) targeted to either cytosol, endosome-lysosomes, or mitochondria. The rate and extent of fluorescence recovery provided an in situ measure of the accessibility of chelators to particular cell sites/organelles. Complementary, fluorogenic redox probes associated with cell compartments enabled identification of chelator-sensitive, localized reactive oxidant production. Our studies indicate that chelation by desferrioxamine is slow and is enhanced in cells with relatively high endocytic activities, while ICL670 and DFP readily enter most cells and efficiently reach the major intracellular sites of iron accumulation.
Three pathways to mature macrophages in the early mouse yolk sac
Authors: Bertrand Julien Y. , Jalil Abdelali , Klaine Michèle , Jung Steffen , Cumano Ana , Godin Isabelle 
Published: July 2005

AbstractThe existence of macrophages (Mφ) of yolk-sac (YS) origin has been reported in all vertebrate models. However, the nature of their precursors and pathways of differentiation have not been elucidated. Phenotypic and differentiation potential analyses of YS at 7.5 to 10 postcoital days (dpc), performed in CX3CR1GFP embryos, allowed us to discern 3 independent Mφ populations. A first transient wave consisted of mature, maternal-derived Mφpresent as early as 7.5 to 8 dpc. A second wave of committed Mφ precursors arose at 8 dpc (2-4 somite stage) and was followed by a third wave of erythromyeloid precursors (4-6 somite stage). Both types of precursors displayed similar phenotypes and gave rise to CX3CR1/green fluorescent protein (GFP)–positive Mφ, but differed by their differentiation potential, at the clonal level. The combined data of phenotypic, gene-expression, and in situ analyses allowed us to conclude that the previously named “primitive Mφ” corresponded to a mixture of the first transient wave and committed Mφ precursors. Both YS-derived precursors followed a developmental pathway common to adult Mφ and could be qualified as definitive.
LPS induces CD40 gene expression through the activation of NF-κB and STAT-1α in macrophages and microglia
Authors: Qin Hongwei , Wilson Cynthia A. , Lee Sun Jung , Zhao Xueyan , Benveniste Etty N. 
Published: July 2005

AbstractCD40 is expressed on various immune cells, including macrophages and microglia. Aberrant expression of CD40 is associated with autoimmune inflammatory diseases such as multiple sclerosis and rheumatoid arthritis. Interaction of Toll-like receptor-4 (TLR4) with the Gram-negative bacteria endotoxin lipopolysaccharide (LPS) results in the induction of an array of immune response genes. In this study, we describe that LPS is a strong inducer of CD40 expression in macrophages and microglia, which occurs at the transcriptional level and involves the activation of the transcription factors nuclear factor-κB (NF-κB) and signal transducer and activator of transcription 1α (STAT-1α). LPS-induced CD40 expression involves the endogenous production of the cytokine interferon-beta (IFN-β), which contributes to CD40 expression by the activation of STAT-1α. Blocking IFN-β–induced activation of STAT-1α by IFN-β–neutralizing antibody reduces LPS-induced CD40 gene expression. Furthermore, LPS induces acetylation and phosphorylation of histones H3 and H4 and the recruitment of NF-κB, STAT-1α, and RNA polymerase II on the CD40 promoter in vivo in a time-dependent manner, all events important for CD40 gene transcription. These results indicate that both LPS-induced NF-κB activation and endogenous production of IFN-β that subsequently induces STAT-1α activation play critical roles in the transcriptional activation of the CD40 gene by LPS.