bluuebunny/crossref_metadata_2025_split huggingface dataset:
Continental‐scale phenology: warming and chilling
Authors: Schwartz Mark D. , Hanes Jonathan M. 
Published: September 2009

AbstractWith abundant evidence of recent climate warming, most vegetation studies have concentrated on its direct impacts, such as modifications to seasonal plant and animal life cycle events (phenology). The most common examples are indications of earlier onset of spring plant growth and delayed onset of autumn senescence. However, less attention has been paid to the implications of continued warming for plant species' chilling requirements. Many woody plants that grow in temperate areas require a certain amount of winter chilling to break dormancy and prepare to respond to springtime warming. Thus, a comprehensive assessment of plant species' responses to warming must also include the potential impacts of insufficient chilling.When collected at continental scale, plant species phenological data can be used to extract information relating to the combined impacts of warming and reduced chilling on plant species physiology. In this brief study, we demonstrate that common lilac first leaf and first bloom phenology (collected from multiple locations in the western United States and matched with air temperature records) can estimate the species' chilling requirement (1748 chilling hours, base 7.2 °C) and highlight the changing impact of warming on the plant's phenological response in light of that requirement. Specifically, when chilling is above the requirement, lilac first leaf/first bloom dates advance at a rate of − 5.0/− 4.2 days per 100‐h reduction in chilling accumulation, while when chilling is below the requirement, they advance at a much reduced rate of − 1.6/− 2.2 days per 100‐h reduction. With continental‐scale phenology data being collected by the USA National Phenology Network (http://www.usanpn.org), these and more complex ecological questions related to warming and chilling can be addressed for other plant species in future studies. Copyright © 2009 Royal Meteorological Society
The economic value of improved agrometeorological information to irrigators amid climate variability
Authors: Mushtaq Shahbaz , Chen Charlie , Hafeez Mohsin , Maroulis Jerry , Gabriel Hamza 
Published: September 2009

AbstractIn Australia, climate variability and the predicted impact of climate change help in making seasonal rainfall less predictable and seasonal irrigation supplies more uncertain, eroding agricultural production prospects and profitability. Water allocation forecasts have economic value to irrigators for making informed cropping decisions. This study estimated the economic value of improved irrigation allocation forecasts in the Coleambally irrigation area (CIA) in southeastern Australia using a non‐linear programming model. The model uses production and profit functions to estimate yield and gross margins for various water allocation levels rather than using given crop yields and gross margins. The model also captures the tactical response of improved cropping decisions made by irrigators based on water allocation announcements throughout the irrigation season. Tactical responses include changing the winter crop combinations, abandoning irrigation for a percentage of the summer crops, temporary purchase or sale of water, and deficit irrigation.The estimated economic benefit of improved seasonal water allocation forecasts to the CIA irrigators ranges from AU$ 1.33 ha−1 to AU$ 9.58 ha−1 (AU$ 1 = US$ 0.77). The economic analysis of water allocation forecasts shows that the potential total gross margin for the irrigators at the 100% allocation level was AU$ 47.6 m, assuming accurate forecast of the end‐of‐season allocations. A more realistic scenario generates a forecast value of AU$ 8.9 million reduction in the gross margin (pessimistic water allocation outlook) and AU$ 1.60 million in the forgone gross margin (optimistic water allocation outlook) for only 5% variation in outlook above or below the actual allocation level of 60%. This suggests that losses far exceed when water allocations are over‐estimated by irrigators, as resources and inputs could be overly committed to execute the less‐informed cropping plans. The knowledge benefits from forecasts are far greater at the lower end of an allocation due to relative water scarcity. However, for higher allocation levels (>80%), the knowledge benefits are negligible due to less water scarcity. Thus, investments in water allocation forecasts and related agrometeorological information could be useful tools for policy makers, farmers, agribusiness, and the insurance industry. Copyright © 2009 Royal Meteorological Society
On lengths of filling closed geodesics of hyperbolic punctured Riemann spheres
Authors: Zhang C. 
Published: September 2009

AbstractLet S be a Riemann sphere with n ≥ 4 points deleted. In this article we investigate certain filling closed geodesics of S and give quantitative common lower bounds for the hyperbolic lengths of those geodesics with respect to any hyperbolic structure on S (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Boundary integral equations for a three‐dimensional Brinkman flow problem
Authors: Kohr Mirela , Wendland Wolfgang L. 
Published: September 2009

AbstractThe purpose of this paper is to prove existence and uniqueness in Sobolev or Hölder spaces for a transmission problem which describes the flow of a viscous incompressible fluid past a porous particle embedded in a second porous medium, by using the Brinkman model and potential theory. Some particular cases, which refer to Stokes flow past a porous particle, or to Brinkman's flow past a void, are also presented together with corresponding asymptotic results for the flow velocity field and the hydrodynamic force exerted on the particle (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An empirical investigation of consumers' procurement of pharmaceutical products via online retail channels
Authors: Rajamma Rajasree K. , Pelton Lou E. 
Published: September 2009

AbstractThe procurement of pharmaceuticals from electronic channels is drawing widespread attention from marketing decision makers, public policymakers, and the popular media. The focus on online retail channels for pharmaceuticals may be, in part, attributable to the potential risks and safety issues that underlie consumers' self‐initiated pharmaceutical acquisition and consumption decisions. Clearly, there exist an unprecedented number of consumers employing this nontraditional channel for procuring both over‐the‐counter (OTC) and prescription pharmaceuticals in the U.S. This study explores the potential impact of consumers' cognitive characteristics on their decision making as it relates to procuring pharmaceutical products via online retail channels. The results of the study indicate that both powerful others health locus of control and objectivism determine the propensity to procure pharmaceuticals via electronic retail channels. Moreover, health value is identified as a portentous moderator of the relationship between consumers' health locus of control, objectivism, and pharmaceuticals procurement via electronic retail channels. The implications of the findings and recommendations for future research are offered, as well. © 2009 Wiley Periodicals, Inc.
High Temperature Interaction Chromatography of Olefin Copolymers
Authors: Pasch Harald , Albrecht Andreas , Bruell Robert , Macko Tibor , Hiller Wolf 
Published: September 2009

AbstractSummary: The synthesis and characterization of polyolefins continues to be one of the most important areas for academic and industrial polymer research. One consequence of the development of new “tailor‐made” polyolefins is the need for new and improved analytical techniques for the analysis of polyolefins with respect to molar mass and chemical composition distribution. The present article briefly reviews different new and relevant chromatographic techniques for polyolefin analysis. For the fast analysis of the chemical composition distribution of polyolefins a new high‐temperature gradient high‐performance liquid chromatography (HPLC) system has been introduced. The efficiency of this system for the separation of various olefin copolymers is demonstrated. The correlation between elution volume and chemical composition can be accessed by on‐line coupling of high temperature HPLC with FTIR spectroscopy. For the elucidation of the chemical composition as a function of molar mass high‐temperature size exclusion chromatography and 1H‐NMR spectroscopy can be coupled. It is shown that the on‐line NMR analysis of chromatographic fractions yields information on microstructure and chemical composition in addition to molar mass distribution.
Characterization of Ethylene Copolymers with Liquid Chromatography and Melt Rheology Methods
Authors: Brun Yefim , Pottiger Michael T 
Published: September 2009

AbstractSummary: Melt rheology and polymer chromatography methods were applied to characterize molecular heterogeneities in products of free radical copolymerization of ethylene with methyl acrylate and vinyl acetate comonomers performed in continuously stirred tank and tubular reactors. We found that the ethylene–vinyl acetate copolymers made in both reactors had similar linear viscoelastic properties typical to branched products of the high pressure process. But the ethylene–methyl acrylate copolymers obtained in the tubular reactor had unusually high melt viscosity at low shear rate and much lower onset of shear thinning despite the narrower molecular weight distribution and the lower overall amount of long‐chain branches compare to their autoclave counterparts with similar average molecular weight and chemical composition. Using interaction polymer chromatography method called gradient elution at critical point of adsorption we found that ethylene‐acrylate copolymers from the tubular reactor had very broad chemical composition distribution, which was consistent with a significant difference in reactivity ratios between ethylene and acrylate comonomers. Such chemical composition heterogeneity can be a reason for the observed unusual rheological properties of these copolymers.
Liquid Chromatographic Separation of Olefin Oligomers and its Relation to Separation of Polyolefins – an Overview
Authors: Macko Tibor , Pasch Harald , Wang Yongmei 
Published: September 2009

AbstractSummary: Linear and branched alkanes are oligomers of polyethylene. Alkanes with higher molar masses are called waxes. These substances are widely used as fuels, oils, lubricants, etc. and for these reasons many groups have tried to analyse, separate and characterise alkanes by various methods, including liquid chromatography. Alkanes may be separated according to their size in solution by SEC. In addition to chromatographic systems separating in the SEC mode, various sorbent‐solvent systems have been published, where alkanes have been separated one from another by adsorption and/or precipitation mechanism. The mobile phase is either a non‐polar solvent or a polar solvent or a mixture of a solvent and a non‐solvent for alkanes. Even near critical conditions, which have several advantages for applications of HPLC in polymer analysis, have been identified for alkanes. Moreover, selective separations of branched alkanes according to their structure have been published. In the majority of these published studies, solvents with low boiling points have been used as the mobile phases, which do not allow dissolution of crystalline polyolefins at atmospheric pressure. However, taking into account experiences with the separation of alkanes, new HPLC systems for the separation of polyolefins may be developed. This is a major challenge and first results are presented in this contribution.
Estimation of Average Comonomer Content of Ethylene/1‐Olefin Copolymers Using Crystallization Analysis Fractionation (Crystaf) and Artificial Neural Network (ANN)
Authors: Anantawaraskul Siripon , Chokputtanawuttilerd Nuttawat 
Published: September 2009

AbstractSummary: An artificial neural network (ANN) with a 4‐3‐3‐1 architecture was developed to estimate average comonomer content of ethylene/1‐olefin copolymers from crystallization analysis fractionation (Crystaf) results. The ANN was trained with a back propagation algorithm. It was found that average comonomer contents predicted from ANN agree well with experimental results for both training and testing data sets. The developed ANN was also used to systematically investigate the effects of chain microstructures and Crystaf operating conditions on Crystaf calibration curves.
Existence of time periodic solutions for the Nicholson's blowflies model with Newtonian diffusion
Authors: Yang Ying , Zhang Ran , Jin Chunhua , Yin Jingxue 
Published: September 2009

AbstractThis paper is concerned with the existence of periodic solutions of the Nicholson's blowflies model with Newtonian diffusion. By constructing some suitable Lyapunov functionals and combining with Leray–Schauder fixed point theorem, we establish the existence of nonnegative time periodic solutions. Copyright © 2009 John Wiley & Sons, Ltd.
Urodynamics prior to treatment as an intervention: A pilot study
Authors: Majumdar Amitabha , Latthe Pallavi , Toozs‐Hobson Philip 
Published: September 2009

AbstractAimsTo evaluate whether the treatment based on urodynamics (UDS) leads to better treatment response compared to where the treatment is based on symptoms alone.Study design, materials and methodsAll patients referred with lower urinary tract symptoms (LUTS) were offered the opportunity to participate in this patient preference trial. Patients were asked to complete a Kings Health Questionnaire (KHQ) and a 3‐day bladder diary. The patients were then offered treatment based on their preference for conservative therapy based on either symptoms alone or with additional UDS or randomization to the same two alternatives, if they had no preference. The primary outcomes studied were improvement in KHQ and reduction in Incontinence Episode Frequency (IEF) at 6 months. Logistic regression analysis was done to evaluate the effect of choice of treatment and effect of incontinence on KHQ.ResultsThere was no statistically significant difference between the KHQ scores pre and post UDS in patient preference or randomized groups. Follow up attendance rates were significantly better in those who chose to undergo urodynamics when compared to those who chose conservative treatment.ConclusionsThis study suggests although UDS does not improve IEF, it may have utility in patient choice and subsequent compliance. Another relevant finding was the previously unreported high uptake of UDS by women when given the choice of whether to undergo UDS first or have treatment based on symptoms alone. Neurourol. Urodynam. 29:522–526, 2010. © 2009 Wiley‐Liss, Inc.
Skeletal analysis and mortuary practice in an Early Roman chamber tomb at Kenchreai, Greece
Authors: Ubelaker D. H. , Rife J. L. 
Published: September 2009

AbstractRecent exploration of the site of Kenchreai, the eastern port of Corinth in southern Greece, has focussed on a cemetery of subterranean chamber tombs dating chiefly to the Early Roman period (middle‐late 1st to 3rd centuries AD). The copious but fragmentary human bones and teeth found in Tomb 10 have been disturbed since burial by natural processes, including bedrock erosion and the infiltration of moisture, roots and basic sediment, and by destructive looters. Nonetheless, the remains furnish considerable information about the mortuary practices of wealthy residents. Analysis of the remains in their archaeological and taphonomic contexts reveals that Tomb 10 contained at least 23 individuals, 15 inhumed in loculi and 8 cremated and placed in niches, sometimes in urns. The identification of males, females and subadults among the burned and unburned bones and teeth suggests that spouses, parents and children probably from several generations of the same lineage or household were buried here. The nature of the cremated fragments reflects a laborious process during which mourners burned bodies on substantial pyres at extremely high temperatures for a long time. Then they carefully extracted a representative sample of small fragments from throughout the reduced skeleton for burial at the tomb. This study contributes to a better understanding of mortuary practices in the Roman East, particularly the Greek world, where the chamber tomb was a common sepulchral type. Copyright © 2009 John Wiley & Sons, Ltd.
Preparation, characterization, thermo‐mechanical, and barrier properties of exfoliated thermoplastic toughened epoxy clay ternary nanocomposites
Authors: Asif A. , Rao V. Lakshmana , Ninan K. N. 
Published: September 2009

AbstractTernary nanocomposites are prepared by blending hydroxyl‐terminated poly ether ether ketone having pendant methyl groups (PEEKMOH) with epoxy resin along with Nanolin DK1, followed by curing with 4,4′‐diamino diphenyl sulphone. Differential scanning calorimetry shows a two‐stage cure behavior indicating the catalytic effect of the primary amine and proton, which are generated by the dissociation of organic modifier. Tensile and flexural moduli are increased while tensile strength and glass transition temperature are decreased with increase in clay concentration. Fracture toughness and strain at break are increased by 59 and 62%, respectively, with 1 phr clay loading. Transition electron microscopy and X‐ray diffraction (XRD) analysis reveal exfoliated morphology for the nanocomposites. Scanning electron micrographs show a decrease in both, domain size as well as inter domain distance of the thermoplastic phase with the addition of clay, indicating the occurrence of gelation before phase separation. Analysis of the fracture surface reveals crack path deflection and ductile fracture behavior, confirming that toughness has been improved with the addition of clay and PEEKMOH. Coefficient of thermal expansion (CTE) of the nanocomposites is decreased up to 3 phr clay loading. Oxygen gas permeability is compared with Bharadwaj's and Neilson's models. A marginal improvement in thermal stability is observed with the addition of clay. Copyright © 2009 John Wiley & Sons, Ltd.
Preparation and characterization of novel negatively charged hybrid membranes
Authors: Xuan Fengqin , Liu Junsheng , Xu Tongwen 
Published: September 2009

AbstractCharged hybrid membranes with anionic‐ or cationic‐exchange groups have attracted increasing interest due to their higher thermal stabilities and structural flexibilities which are considered suitable for use in some harsh conditions, such as higher temperature and strongly oxidizing circumstances, for industrial applications. To develop new routes to synthesize the negatively charged hybrid membranes, a series of hybrid membranes were prepared via free radical polymerization of glycidylmethacrylate (GMA) and γ‐methacryloxypropyl trimethoxy silane (MPTMS) monomers, and ring‐opening of epoxide to create negatively charged SO3H groups in the polymer chains. The fundamental properties of these prepared membranes were characterized through TGA, ion‐change capacity (IEC), and MALDI–TOF mass spectra. TGA showed that the thermal degradation temperature of these membranes could reach up to 300°C and the temperature of the first endothermic peak decreased with an increase in the content of SO3H groups. IEC measurements showed that their IECs were within the range of 0.22–0.35 mmol g−1. MALDI–TOF spectrometry indicated that the incorporation of GMA into the hybrid matrix could improve the structural stability of the membranes. These findings demonstrated that the ion‐exchange properties and structural stability of negatively charged hybrid membranes can be conveniently controlled by adjusting the GMA moiety in the hybrid matrix. Copyright © 2009 John Wiley & Sons, Ltd.
Administration of high‐dose interleukin‐2 in a 2‐year‐old with metastatic melanoma
Authors: Bernhardt M. Brooke , Hicks M. John , Pappo Alberto S. 
Published: September 2009

AbstractMalignant melanoma is rare in pediatrics, and therapies for patients with disseminated disease have not been well studied. This report describes our experience with the use of high‐dose interleukin 2 (aldesleukin, IL‐2) in a 2‐year‐old child with metastatic melanoma and describes our approach for the administration of this agent to young patients. Pediatr Blood Cancer 2009; 53:1346–1348. © 2009 Wiley‐Liss, Inc.
Value‐centric framework and pareto optimality for design and acquisition of communication satellites
Authors: Brathwaite Joy , Saleh Joseph H. 
Published: September 2009

AbstractInvestments in space systems are substantial, indivisible, and irreversible, characteristics of high‐risk investments. Traditional approaches to system design, acquisition, and risk mitigation are derived from a cost‐centric mindset, and as such they incorporate little information about the value of the spacecraft to its stakeholders. These traditional approaches are appropriate in stable environments. However, the current technical and economic conditions are distinctly uncertain and rapidly changing. Consequently, these traditional approaches have to be revisited and adapted to the current context.We propose that in uncertain environments, decision‐making with respect to design and acquisition choices should be value‐based. We develop a value‐centric framework, analytical tools, and an illustrative numerical example for communication satellites. Our two proposed metrics for decision‐making are the system's expected value and value uncertainty. Expected value is calculated as the expected NPV of the satellite. The cash inflow is calculated as a function of the satellite loading, its transponder pricing, and market demand. The cash outflows are the various costs for owning and operating the satellite. Value uncertainty emerges due to uncertainties in the various cash flow streams, in particular because of market conditions. We propagate market uncertainty through Monte Carlo simulation, and translate it into value uncertainty for the satellite. The end result is a portfolio of Pareto‐optimal satellite design alternatives.By using value and value uncertainty as decision metrics in the down‐selection process, decision‐makers draw on more information about the system in its environment, and in making value‐based design and acquisition choices, they ultimately make more informed and better choices. Copyright © 2009 John Wiley & Sons, Ltd.
Perceptions on the demand side and realities on the supply side: a study of the South African table grape export industry
Authors: Müller Claribel , Vermeulen Walter J. V. , Glasbergen Pieter 
Published: September 2009

AbstractThis article reports on the mechanisms of business‐to‐business regulation as governance approach in an agricultural supply chain. The article explores the activities of NGOs, government and business in promoting sustainable production. It focuses on the requirements set for producers in agro‐food chains and the effects of NGO perceptions on these issues. The subsequent business standards set by retailers and other market role‐players and the responses of producers are reported and the responsibility for achieving desired outputs is discussed. The research methodology included open interviews with various stakeholders in the chain, as well as structured questionnaires to determine practices on farms. From the findings it is clear that perceptions of European stakeholders differ substantially from the reality found in South Africa. This has consequences for producers, from both a social and a financial perspective. Understanding the role and function of NGOs, market role‐players and national government in the governance of sustainable development in the South African–European table grape supply chain contributes to identifying barriers and opportunities to achieving sustainable practices in global supply chains. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.