bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resource defense and monopolization in a marked population of ruby‐throated hummingbirds (Archilochus colubris)
Authors: Rousseu François , Charette Yanick , Bélisle Marc 
Published: February 2014

AbstractResource defense behavior is often explained by the spatial and temporal distribution of resources. However, factors such as competition, habitat complexity, and individual space use may also affect the capacity of individuals to defend and monopolize resources. Yet, studies frequently focus on one or two factors, overlooking the complexity found in natural settings. Here, we addressed defense and monopolization of nectar feeders in a population of free‐ranging ruby‐throated hummingbirds marked with passive integrated transponder (PIT tags). Our study system consisted of a 44 ha systematic grid of 45 feeders equipped with PIT tag detectors recording every visit made at feeders. We modeled the number of visits by competitors (NVC) at feeders in response to space use by a focal individual potentially defending a feeder, number of competitors, nectar sucrose concentration, and habitat visibility. Individuals who were more concentrated at certain feeders on a given day and who were more stable in their use of the grid throughout the season gained higher exclusivity in the use of those feeders on that day, especially for males competing against males. The level of spatial concentration at feeders and its negative effect on NVC was, however, highly variable among individuals, suggesting a continuum in resource defense strategies. Although the apparent capacity to defend feeders was not affected by competition or nectar sucrose concentration, the level of monopolization decreased with increasing number of competitors and higher nectar quality. Defense was enhanced by visibility near feeders, but only in forested habitats. The reverse effect of visibility in open habitats was more difficult to interpret as it was probably confounded by perch availability, from which a bird can defend its feeder. Our study is among the first to quantify the joint use of food resource by overlapping individuals unconstrained in their use of space. Our results show the importance of accounting for variation in space use among individuals as it translated into varying levels of defense and monopolization of feeders regardless of food resource distribution.
Quantifying the effects of elevated CO2 on water budgets by combining FACE data with an ecohydrological model
Authors: Cheng Lei , Zhang Lu , Wang Ying‐Ping , Yu Qiang , Eamus Derek 
Published: February 2014

ABSTRACTResponse of leaf area index (LAI) is the key determinant for predicting impacts of the elevated CO2 (eCO2) on water budgets. Importance of the changes in functional attributes of vegetation associated with eCO2 for predicting responses of LAI has rarely been addressed. In this study, the WAter Vegetation Energy and Solute (WAVES) model was applied to simulate ecohydrological effects of the eCO2 at two free‐air CO2 enrichment (FACE) experimental sites with contrasting vegetation. One was carried out by the Oak Ridge National Laboratory on the forest (ORNL FACE). The other one was conducted by the University of Minnesota on the grass (BioCON FACE). Results demonstrated that changes in functional attributes of vegetation (including reduction in specific leaf area, changes in carbon assimilation and allocation characteristics) and availability of nutrients are important for reproducing the responses of LAI, transpiration and soil moisture at both sites. Predicted LAI increased slightly at both sites because of fertilization effects of the eCO2. Simulated transpiration decreased 10·5% at ORNL site and 13·8% at BioCON site because of reduction in the stomatal conductance. Predicted evaporation from interception and soil surface increased slightly (<1·0 mm year−1) at both sites because of increased LAI and litter production, and increased soil moisture resulted from reduced transpiration. All components of run‐off were predicted to increase because of significant decrease in transpiration. Simulated mean annual evapotranspiration decreased about 8·7% and 10·8%, and mean annual run‐off increased about 11·1% (59·3 mm year−1) and 9·5% (37·6 mm year−1) at the ORNL and BioCON FACE sites, respectively. Copyright © 2014 John Wiley & Sons, Ltd.
Riparian and in‐stream restoration of boreal streams and rivers: success or failure?
Authors: Nilsson Christer , Polvi Lina E. , Gardeström Johanna , Hasselquist Eliza Maher , Lind Lovisa , Sarneel Judith M. 
Published: February 2014

AbstractWe reviewed follow‐up studies from Finnish and Swedish streams that have been restored after timber floating to assess the abiotic and biotic responses to restoration. More specifically, from a review of 18 case studies (16 published and 2 unpublished), we determined whether different taxonomic groups react differently or require different periods of time to respond to the same type of restoration. Restoration entailed returning coarse sediment (cobbles and boulders) and sometimes large wood to previously channelized turbulent reaches, primarily with the objective of meeting habitat requirements of naturally reproducing salmonid fish. The restored streams showed a consistent increase in channel complexity and retention capacity, but the biotic responses were weak or absent in most species groups. Aquatic mosses growing on boulders were drastically reduced shortly after restoration, but in most studies, they recovered after a few years. Riparian plants, macroinvertebrates and fish did not show any consistent trends in response. We discuss seven alternative explanations to these inconsistent results and conclude that two decades is probably too short a time for most organisms to recover. We recommend long‐term monitoring using standardized methods, a landscape‐scale perspective and a wider range of organisms to improve the basis for judging to what extent restoration in boreal streams has achieved its goal of reducing the impacts from timber floating. Copyright © 2014 John Wiley & Sons, Ltd.
Simultaneous measurements of stem radius variation and sap flux density reveal synchronisation of water storage and transpiration dynamics in olive trees
Authors: Cocozza Claudia , Marino Giovanni , Giovannelli Alessio , Cantini Claudio , Centritto Mauro , Tognetti Roberto 
Published: February 2014

AbstractContinuous stem water relations, sap flux and radial variation, and soil moisture were monitored in rainfed and irrigated mature olive (Olea europaea L.) trees in field conditions in central Italy. A mathematical procedure was applied to describe plant–environment dependences in order to facilitate the identification of the correspondence between stem factors (sap flow and diameter variation) and environmental parameters (water availability and evaporative demand). A direct correspondence between the time series of the monitored parameters was observed in the two growing seasons. Soil water content was synchronous to stem diameter variation in irrigated trees, whereas they were asynchronous in rainfed conditions. On a daily basis, sap flux density showed an opposite trend with respect to patterns of vapour pressure deficit and evapotranspiration (ET0) in spring, corresponded to the course of ET0 in summer and lagged behind ET0 in autumn. Maximum daily shrinkage was correlated with vapour pressure deficit (R2 = 0.50, in rainfed; R2 = 0.51, in irrigated plants), whereas it was not significantly related to ET0. Conversely, cumulative sap flow showed a good relationship with ET0 (R2 = 0.60, in rainfed; R2 = 0.51, in irrigated plants) and scaled exponentially with maximum daily shrinkage (R2 = 0.56, in rainfed; R2 = 0.61, in irrigated plants), indicating consistent radial transfer of water between xylem and phloem. The proposed analytical approach highlights the importance of combining measured parameters and sensor outputs in order to determine adjustments of specific plant functionality traits, such as the dynamics of water status in trees, for modelling and practical uses. This study also indicates a different accounting of the effect of microclimatic variables on plant signals based on stem sensors. Copyright © 2014 John Wiley & Sons, Ltd.
Copper‐Catalyzed Decarboxylative Methylation of Aromatic Carboxylic Acids with PhI(OAc)2
Authors: Jiang Yuyu , Pan Shulei , Zhang Yanghui , Yu Jingxun , Liu Hongqiang 
Published: February 2014

AbstractThe copper‐catalyzed decarboxylative methylation of aromatic carboxylic acids was developed by using PhI(OAc)2 to provide a new strategy for the methylation of aryl acids through the decarboxylation of alkyl acids. The mechanism and the roles of each reactant in the reaction were investigated extensively.
Compact Electrochemical Flow System for the Analysis of Environmental Pollutants
Authors: Gutiérrez‐Capitán Manuel , Ipatov Andrey , Merlos Ángel , Jiménez‐Jorquera Cecilia , Fernández‐Sánchez César 
Published: February 2014

AbstractA compact flow system that includes two electrochemical transducers integrated in a miniaturized cell is reported. Each transducer shows an on‐chip thin‐film gold three‐electrode configuration. The cell was machined on polymethyl methacrylate substrates, together with the required minifluidic elements for sample conditioning and analysis. These include several pumps and valves that enabled the system to work in an automatic fashion. Its performance was assessed by analyzing copper, catechol and parathion, using different chronoamperometric approaches. A rapid and reproducible response, ease of use, simple data interpretation and low maintenance make the system amenable to be implemented in a portable instrument for on‐site environmental analysis.
Application of PEDOT‐CNT Microelectrodes for Neurotransmitter Sensing
Authors: Samba Ramona , Fuchsberger Kai , Matiychyn Ilona , Epple Sebastian , Kiesel Lydia , Stett Alfred , Schuhmann Wolfgang , Stelzle Martin 
Published: February 2014

AbstractIn this work, composite microelectrodes from poly(3,4‐ethylenedioxythiophene) (PEDOT) and carbon nanotubes (CNT) are characterized as electrochemical sensing material for neurotransmitters. Dopamine can be detected using square wave voltammetry at these microelectrodes. The CNTs improve the sensitivity by a factor of two. In addition, the selectivity towards dopamine in the presence of ascorbic acid and uric acid was examined. While both electrodes, PEDOT and PEDOT‐CNT are able to detect all measured concentrations of dopamine in the presence of uric acid, small concentrations of dopamine and ascorbic acid are only distinguishable at PEDOT‐CNT electrodes. Changing the pH has a strong influence on the selectivity. Moreover, it is possible to detect concentrations as low as 1 µM dopamine in complex cell culture medium. Finally, other catecholamines like serotonin, epinephrine, norepinephrine and L‐dopa are also electrochemically detectable at PEDOT‐CNT microelectrodes.
Facilitated Transport of Ions and Glucose by Amphotericin B Across Lipid Bilayers in the Presence or Absence of Cholesterol
Authors: Kagohashi Hiroki , Shirai Osamu , Kubota Shintaro , Kitazumi Yuki , Kano Kenji 
Published: February 2014

AbstractThe transport of ions and glucose across bilayer lipid membranes (BLM) facilitated by amphotericin B (AmB) is studied by use of planar BLMs and liposomal membranes. The transport characteristics change with time in the presence of cholesterol, while it is independent of time in the absence of cholesterol. The carrier‐type transport is observed immediately after the addition of AmB. In the presence of cholesterol, AmB forms a 1 : 1 complex with cholesterol and the channel is formed by aggregation of AmB‐cholesterol complexes. It is concluded that the number of the channels increases with time and that the carrier‐type transport decreases instead.
Detection and Quantification of Sulfonamide Antibiotic Residues in Milk Using Scanning Electrochemical Microscopy
Authors: Conzuelo Felipe , Stratmann Lutz , Grützke Stefanie , Pingarrón José M. , Schuhmann Wolfgang 
Published: February 2014

AbstractThe use of scanning electrochemical microscopy (SECM) for the qualitative and quantitative determination of sulfapyridine (SPY) in milk is described. A direct competitive immunoassay was performed involving an antibiotic horseradish peroxidase (HRP)‐labeled analog and using selective capture antibodies immobilized on the surface of Protein G‐modified glassy carbon plates. SECM detection was accomplished by means of the sample generator/tip collector (GC) mode involving the reduction of benzoquinone (BQ) generated upon the HRP‐catalyzed oxidation of hydroquinone (HQ) at the modified substrate surface in the presence of H2O2. The detection limit for SPY in milk samples was as low as 0.13 ng mL−1.
Modelling soil water dynamics considering measurement uncertainty
Authors: Kisekka Isaya , Migliaccio K. W. , Muñoz‐Carpena R. , Schaffer B. , Khare Y. 
Published: February 2014

AbstractIn shallow water table‐controlled environments, surface water management impacts groundwater table levels and soil water dynamics. The study goal was to simulate soil water dynamics in response to canal stage raises considering uncertainty in measured soil water content. Water and Agrochemicals in the soil, crop and Vadose Environment (WAVE) was applied to simulate unsaturated flow above a shallow aquifer. Global sensitivity analysis was performed to identify model input factors with the greatest influence on predicted soil water content. Nash–Sutcliffe increased and Root Mean Square Error reduced when uncertainties in measured data were considered in goodness‐of‐fit calculations using measurement probability distributions and probable asymmetric error boundaries, implying that appropriate model performance evaluation should be carried out using uncertainty ranges instead of single values. Although uncertainty in the experimental measured data limited evaluation of the absolute predictions by the model, WAVE was found a useful exploratory tool for estimating temporal variation in soil water content. Visual analysis of soil water content time series under proposed changes in canal stage management indicated that sites with land surface elevation of less than 2.0‐m NGVD29 were predicted to periodically experience saturated conditions in the root zone and shortening of the growing season if canal stage is raised more than 9 cm and maintained at this level. The models developed could be combined with high‐resolution digital elevation models in future studies to identify areas with the greatest risk of experiencing saturated root zone. The study also highlighted the need to incorporate measurement uncertainty when evaluating performance of unsaturated flow models. Copyright © 2014 John Wiley & Sons, Ltd.
The Order of Automorphisms of Quasigroups
Authors: McKay Brendan D. , Wanless Ian M. , Zhang Xiande 
Published: February 2014

AbstractWe prove quadratic upper bounds on the order of any autotopism of a quasigroup or Latin square, and hence also on the order of any automorphism of a Steiner triple system or 1‐factorization of a complete graph. A corollary is that a permutation σ chosen uniformly at random from the symmetric group will almost surely not be an automorphism of a Steiner triple system of order n, a quasigroup of order n or a 1‐factorization of the complete graph . Nor will σ be one component of an autotopism for any Latin square of order n. For groups of order n it is known that automorphisms must have order less than n, but we show that quasigroups of order n can have automorphisms of order greater than n. The smallest such quasigroup has order 7034. We also show that quasigroups of prime order can possess autotopisms that consist of three permutations with different cycle structures. Our results answer three questions originally posed by D. Stones.
Extensions of Fractional Precolorings Show Discontinuous Behavior
Authors: van den Heuvel Jan , Král' Daniel , Kupec Martin , Sereni Jean‐Sébastien , Volec Jan 
Published: February 2014

AbstractWe study the following problem: given a real number k and an integer d, what is the smallest ε such that any fractional ‐precoloring of vertices at pairwise distances at least d of a fractionally k‐colorable graph can be extended to a fractional ‐coloring of the whole graph? The exact values of ε were known for and any d. We determine the exact values of ε for if , and if , and give upper bounds for if , and if . Surprisingly, ε viewed as a function of k is discontinuous for all those values of d.
Genomic and transcriptional alterations of cholangiocarcinoma
Authors: Ito Takeshi , Sakurai‐Yageta Mika , Goto Akiteru , Pairojkul Chawalit , Yongvanit Puangrat , Murakami Yoshinori 
Published: February 2014

Abstract Cholangiocarcinoma (CCA) is one of the representative cancers refractory to any therapeutic approach. The incidence of CCA is highest in the northeastern part of Thailand, where chronic inflammation caused by liver fluke (Opisthorchis viverrini: Ov) infection is a major etiologic factor. The incidence of CCA is also increasing in other countries, including Japan. Here, we overview the genetic and transcriptional alterations of CCA with and without association with Ov infection. CCA with Ov shows enhanced expression of the genes involved in xenobiotic metabolism and chronic inflammatory responses, including cytokine signaling, whereas CCA without Ov shows enhanced expression of growth factor signaling, such as HER2. Exome and the following prevalence sequencing identified mutations of the BAP1, ARID1A, IDH1 and IDH2 genes in CCA, in addition to the high incidence of known mutations in the TP53, KRAS2 SMAD4, and CDKN2A genes, suggesting the role of chromatin modulators in CCA pathogenesis. CCA with Ov shows significantly higher incidence of the TP53 gene mutation, whereas CCA without Ov showed significantly more frequent mutations of the BAP1, IDH1 and IDH2 genes. However, CCAs with Ov and without Ov share a similar mutation spectrum dominated by C : G > T : A transitions mainly at CpG dinucleotides, suggesting that CCA shares etiologic factors with pancreatic ductal carcinoma but not with hepatocellular carcinoma. Comprehensive analyses of the genetic and transcriptional alterations of CCA with and without Ov infection would provide useful information for the prevention, early diagnosis, and treatment of CCA.
How to expand the safe limits in hepatic resections?
Authors: Asencio José Manuel , García Sabrido José Luis , Olmedilla Luis 
Published: February 2014

Abstract The size of the remnant liver after an extended hepatectomy is currently the main limiting factor for performing curative hepatic surgery in patients with tumors and liver metastasis. The current guidelines for extended hepatectomies require that the future remnant liver volume needs to be higher than 20% of the original liver in healthy organs, of 30% in livers with steatosis or exposed to chemotherapy, and of 40% in patients with cirrhosis in order to prevent the “small‐for‐size” syndrome, characterized by the development of liver dysfunction with ascites, coagulopathy and cholestasis. Observations from the use of small liver grafts in liver transplantation and an increased surgical experience has improved our understanding of the mechanisms responsible for the development of liver dysfunction after extended hepatectomies. Increasing the size of the future liver remnant, the introduction of the “small‐for‐flow” concept with the perioperative monitoring and modulation of portal blood flow and pressure, and the exploration of the potential effects of regeneration preconditioning, are all promising strategies that could expand the indications and increase the safety of liver surgery.
Leadership Education Across Disciplines: The Social Science Perspective
Authors: Perruci Gama 
Published: February 2014

AbstractThe current article makes a distinction between pedagogical delivery and “disciplinary foundations” in our approaches to leadership studies. Although the liberal arts are helpful in the delivery of leadership content in the classroom, it is argued that the content, at its core, remains a social science enterprise. Therefore, leadership programs should help students understand how leadership works as a social phenomenon. The current article shows how the McDonough curriculum moves students beyond leadership training (with its focus on skill building), using a social science–based working definition of leadership. Leadership education provides the opportunity to organize the curriculum using the social science lenses. By moving the focus away from the leader and examining instead the complex interaction of multiple components, a deeper understanding of how leadership works under different contexts, influenced by a variety of societal norms and values can be obtained.
Does bias correction increase reliability of flood projections under climate change? A case study of large rivers in Germany
Authors: Huang Shaochun , Krysanova Valentina , Hattermann Fred F. 
Published: February 2014

ABSTRACTThere is a large uncertainty associated with flood projections driven by different climate scenarios. The bias‐corrected regional climate scenarios are widely used to drive hydrological models in climate impact studies, but there are also doubts and questions about the application of bias correction (BC) methods. This study aims to investigate the performance and impacts of BCs on flood projections in Germany. The distribution mapping method was applied to correct the climate data from the regional climate models (RCMs) CCLM (Cosmo‐Climate Local Model) and REMO (REgional MOdel) developed in Germany. The results show that BC can effectively reduce bias in the simulated average annual discharge, but the uncertainty of simulated floods remains due to the imperfect correction of extreme precipitations. About 75% of the change directions in the 50‐year flood discharge remain the same before and after the BC was used. The relatively short control period of 40 years and the assumption of stationarity of the BC method are two important and problematic issues for flood projections. Hence, it is difficult to prove that BC can increase reliability of flood projections. The direct use of RCM outputs for the control and scenario periods may still be useful for flood impact studies. In addition, a bilateral analysis of RCM and hydrological model performance involving the meteorologists and hydrologists could be helpful for reducing the bias of the RCM outputs in the future.