bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessing the rate and timing of leaf wax regeneration in Fraxinus americana using stable hydrogen isotope labeling
Authors: Gao Li , Tsai Yih‐Jin , Huang Yongsong 
Published: August 2012

RATIONALEUnderstanding leaf wax regeneration and recycling is crucial for plant physiology and paleoclimate studies. However, our recent isotope labeling experiments on a grass species (Phleum pratense) yielded different conclusions from published data on a tree species (Populus trichocarpa), with the former showing rapid regeneration and the latter little regeneration in mature leaves. It is therefore important to determine if the discrepancies in published results were due to differing dynamics of leaf wax regeneration and/or caveats in experimental methods.METHODSLeaves from a native New England tree species (Fraxinus americana) were collected at 1 to 3 h intervals over a 2‐day experimental period, and, subsequently, the leaf wax δ2H isotopic ratios were measured using gas chromatography/isotope ratio mass spectrometry.RESULTSIt was necessary to irrigate the tree using water with significantly higher δ2H values than that used for the grass in order to obtain readily measurable isotopic responses over diurnal cycles. In addition, diurnal leaf wax regeneration in Fraxinus americana was delayed by 1–4 h relative to Phleum pratense, suggesting that the latter produced leaf waxes from more recently photosynthesized substrates.CONCLUSIONSThe isotopic inertia in Fraxinus americana was due to lower leaf wax regeneration rates than in Phleum pratense by one to two orders of magnitude. The difference in the timing of leaf wax biosynthesis might partially account for the observed leaf wax hydrogen isotopic difference between trees and grasses. Copyright © 2012 John Wiley & Sons, Ltd.
Dual observer‐based compensators for nonlinear systems
Authors: Deutscher Joachim 
Published: August 2012

SUMMARYIn this article, the concept of dual observer‐based compensators is extended from linear to nonlinear systems. It is shown that a dual observer‐based compensator achieves stabilization by rendering an invariant manifold attractive in which desired dynamics can be assigned. The design of these compensators for nonlinear systems is considerably simple if a flat output of the system to be controlled is known which is illustrated by means of a simple example. Copyright © 2012 John Wiley & Sons, Ltd.
Dynamic anti‐windup design in anticipation of actuator saturation
Authors: Wu Xiongjun , Lin Zongli 
Published: August 2012

SUMMARYIn a traditional anti‐windup design, the anti‐windup mechanism is set to be activated as soon as the control signal saturates the actuator. A recent innovation of delaying the activation of the anti‐windup mechanism, both static and dynamic, until the saturation reaches a certain level of severity has led to a performance improvement of the resulting closed‐loop system. It has been shown that significant further performance improvements can be obtained by activating a static anti‐windup mechanism in anticipation of actuator saturation, instead of immediate or delayed activation. This paper demonstrates that anticipatory activation of a dynamic anti‐windup mechanism would also lead to significant performance improvements over both the immediate and delayed activation schemes.Copyright © 2012 John Wiley & Sons, Ltd.
Critical behavior in inhomogeneous random graphs
Authors: van der Hofstad Remco 
Published: August 2012

AbstractWe study the critical behavior of inhomogeneous random graphs in the so‐called rank‐1 case, where edges are present independently but with unequal edge occupation probabilities. The edge occupation probabilities are moderated by vertex weights, and are such that the degree of vertex i is close in distribution to a Poisson random variable with parameter wi, where wi denotes the weight of vertex i. We choose the weights such that the weight of a uniformly chosen vertex converges in distribution to a limiting random variable W. In this case, the proportion of vertices with degree k is close to the probability that a Poisson random variable with random parameter W takes the value k. We pay special attention to the power‐law case, i.e., the case where
\documentclass{article}\usepackage{mathrsfs}\usepackage{amsmath, amssymb}\pagestyle{empty}\begin{document}\begin{align*}{\mathbb{P}}(W\geq k)\end{align*} \end{document}
is proportional to k‐(τ‐1) for some power‐law exponent τ > 3, a property which is then inherited by the asymptotic degree distribution.We show that the critical behavior depends sensitively on the properties of the asymptotic degree distribution moderated by the asymptotic weight distribution W. Indeed, when
\documentclass{article}\usepackage{mathrsfs}\usepackage{amsmath, amssymb}\pagestyle{empty}\begin{document}\begin{align*}{\mathbb{P}}(W > k) \leq ck^{-(\tau-1)}\end{align*} \end{document}
for all k ≥ 1 and some τ > 4 and c > 0, the largest critical connected component in a graph of size n is of order n2/3, as it is for the critical Erdős‐Rényi random graph. When, instead,
\documentclass{article}\usepackage{mathrsfs}\usepackage{amsmath, amssymb}\pagestyle{empty}\begin{document}\begin{align*}{\mathbb{P}}(W > k)=ck^{-(\tau-1)}(1+o(1))\end{align*} \end{document}
for k large and some τ∈(3,4) and c > 0, the largest critical connected component is of the much smaller order n(τ‐2)/(τ‐1). © 2012 Wiley Periodicals, Inc. Random Struct. Alg., 42, 480–508, 2013
Mixing times for the Swapping Algorithm on the Blume‐Emery‐Griffiths model
Authors: Ebbers Mirko , Knöpfel Holger , Löwe Matthias , Vermet Franck 
Published: August 2012

AbstractWe analyze the so called Swapping Algorithm, a parallel version of the well‐known Metropolis‐Hastings algorithm, on the mean‐field version of the Blume‐Emery‐Griffiths model in statistical mechanics. This model has two parameters and depending on their choice, the model exhibits either a first, or a second order phase transition. In agreement with a conjecture by Bhatnagar and Randall we find that the Swapping Algorithm mixes rapidly in presence of a second order phase transition, while becoming slow when the phase transition is first order. © 2012 Wiley Periodicals, Inc. Random Struct. Alg., 45, 38–77, 2014
Synthesis and characterization of two pet radioligands for the metabotropic glutamate 1 (mGlu1) receptor
Authors: Huang Yiyun , Narendran Rajesh , Bischoff Francois , Guo Ningning , Bae Sung A. , Hwang Dah‐Ren , Lesage Anne S. , Laruelle Marc 
Published: August 2012

AbstractThe metabotropic glutamate 1 receptor (mGlu1) is an important protein in the regulation of glutamate transmission in the brain, and believed to be involved in disorders such as ischemia, epilepsy, neuropathic pain, anxiety, and schizophrenia. The goal of this study was to evaluate two selective mGlu1 antagonists [11C]3 and [18F]4 as potential PET radioligands for the in vivo imaging of the mGlu1 receptor. Biodistribution studies in rats indicated high uptake of [11C]3 and [18F]4 in the brain. The highest activity level was found in the cerebellum, followed by striatum, hippocampus, frontal cortex, and medulla, in a pattern consistent with the distribution of mGlu1 receptor in rat. At 30 min postinjection, the activity ratio of cerebellum to medulla was 4.5 for [11C]3, indicating a high degree of specific binding, while specific binding was lower for [18F]4 (cerebellum to medulla activity ratio of 2.0). Moreover, binding of the radioligands [11C]3 and [18F]4 in mGlu1 receptor‐rich region such as cerebellum was blocked by pretreatment of the rats with their respective unlabeled compound or the selective mGlu1 antagonist (compound 5, 2 mg/kg each), but not by the selective mGlu2 antagonist LY341495, or the selective mGlu5 antagonist MPEP (2 mg/kg), thus indicating the binding specificity and selectivity of [11C]3 and [18F]4 to the mGlu1 receptor. However, in imaging experiments in baboons [11C]3 displayed a small specific binding signal only in the cerebellum, while the specific binding of [18F]4 was difficult to detect. Species differences in receptor density and affinity of the radioligands in large part account for the differences in the behavior of [11C]3 and [18F]4 in rats and baboons. Radioligands with higher affinity and/or lower lipophilicity are needed to successfully image the mGlu1 receptor in humans. Synapse, 2012. © 2012 Wiley Periodicals, Inc.
Investigation of Park–Ang damage index model for flexural behavior of reinforced concrete columns
Authors: Rajabi Roohollah , Barghi Mostafa , Rajabi Reza 
Published: August 2012

SUMMARYOne of the most popular damage indexes for reinforced concrete (RC) members is Park–Ang damage index model. This model has been established on the basis of experimental results of RC beams and columns with different modes of damage. It has considerable uncertainty on the basis of its authors' remarks. In this study, precision of Park–Ang model for RC columns is improved by using some experimental results from Pacific Earthquake Engineering Research information bank. In proposed model, it focused on RC columns with specific sections and collapse modes. Finally, in order to define damage index more exactly in concrete columns under seismic loadings, capability of IDARC‐2D computer program has been improved by this proposed model. Copyright © 2012 John Wiley & Sons, Ltd.
Development of a geophysic model output statistics module for improving short‐term numerical wind predictions over complex sites
Authors: Bédard Joël , Yu Wei , Gagnon Yves , Masson Christian 
Published: August 2012

ABSTRACTDeveloped for short‐term (0–48 h) wind power forecasting purposes, high‐resolution meteorological forecasts for Eastern Canada are available from Environment Canada's Numerical Weather Prediction (NWP) model configured on a limited area (GEM‐LAM). This paper uses 3 years of forecast data from this model for the region of North Cape (Prince Edward Island, Canada). Although the model resolution is relatively high (2.5 km), statistical analysis and site inspection reveal that the model does not have a sufficiently refined grid to properly represent the meteorological phenomena over this complex coastal site. To cope with such representation error, a generalized Geophysic Model Output Statistics (GMOS) module is developed and applied to reduce the forecast error of the NWP forecasts. GMOS differs from other Model Output Statistics (MOS) that are widely used by meteorological centres in the following aspects: (i) GMOS takes into account the surrounding geophysical parameters such as surface roughness, terrain height, etc., along with wind direction; (ii) GMOS can be directly applied for model output correction without any training.Compared with other methods, GMOS using a multiple grid point approach improves the GEM‐LAM predictions root mean squared error by 1–5% for all time horizons and most meteorological conditions. Also, the topographic signature of the forecast error (uneven directional distribution of the forecast error related to the surface characteristics) due to misrepresentation issues is significantly reduced. The NWP forecasts combined with GMOS outperform the persistence model from a 2 h horizon, instead of 3 h using MOS. Finally, GMOS is applied and validated at two other sites located in New Brunswick, Canada. Similar improvements on the forecasts were observed, thus showing the general applicability of GMOS. Copyright © 2012 John Wiley & Sons, Ltd.
Mesh and load distribution requirements for actuator line CFD simulations
Authors: Shives Michael , Crawford Curran 
Published: August 2012

ABSTRACTFundamental numerical testing has been carried out to determine mesh density and force distribution guidelines for an actuator line‐based computational fluid dynamics method for simulating kinetic turbines. The method computes forces from lifting surfaces (i.e. wings or blades) by using the evolving flowfield and tabulated airfoil data. The forces are applied to the flow as momentum source terms distributed with a Gaussian smoothing function about the physical locations of the blade/wing quarter‐chord line. The chosen length scale of the Gaussian distribution affects the magnitude and distribution of the resulting induction and necessitates a minimum grid resolution for accurate results. Tests have been conducted to determine appropriate distribution length scales and mesh spacing by using an infinite span wing and finite span wings with constant and elliptical spanwise circulation distributions. These test cases were chosen because they have simple analytical solutions derived from lifting line theory. The eventual goal is to simulate turbine rotors; however, these fundamental test cases provide a means to evaluate the required mesh spacing and the appropriate distribution length scale without the complexity of modeling a turbine rotor wake. It was found that the source distribution length scale ϵ should be proportional to the local airfoil chord length c with a ratio ϵ / c of approximately 1/4 and that the mesh spacing at the actuator line should satisfy ϵ / Δgrid ≥ 4. This limit is likely somewhat code specific and should be evaluated for all solvers used for actuator line simulations. Copyright © 2012 John Wiley & Sons, Ltd.
Data‐free speculation does not make for testable hypotheses: A reply to Ripple et al.
Authors: Hodges Karen E. 
Published: August 2012

AbstractThe role of top predators in structuring ecosystems is receiving substantial attention from ecologists. Ripple et al. (2011) recently posed a tentatively supported hypothesis that wolves (Canis lupus) may help restore populations of the U.S. federally Threatened Canada lynx (Lynx canadensis), a specialist predator on snowshoe hares (Lepus americanus), through 2 possible mechanisms: a) decreases in the numbers of coyotes (C. latrans), which may compete with lynx for hares as prey and may also kill lynx; or b) decreases in ungulates that might compete with hares for food. These speculative opinions are not supported by current data, either across the range or in the extended example of Yellowstone National Park (YNP) that Ripple et al. provide. The coyote hypothesis lacks the required quantification of coyote numbers and predation rates on hares, both in YNP and across the range of lynx. The browse competition hypothesis ignores substantial differences in browse and habitat preferences between elk (Cervus elaphus) or livestock and hares that prevent competition for food. Our previous work in YNP (Hodges et al. 2009) showed scattered and very low densities of snowshoe hares, with distributions driven by the substantial fire‐related habitat changes YNP has experienced over the past century. Although I applaud their interest in lynx conservation, the unsupported speculations of Ripple et al. do not advance our ability to manage lynx or hares, nor do they present plausible directions for conservation research. © 2012 The Wildlife Society.
Analysis of One and Two-Story Single Family Home Fire Dynamics and the Impact of Firefighter Horizontal Ventilation
Authors: Kerber Stephen 
Published: August 2012

Abstract
This paper describes experimental investigations on fire service ventilation practices in modern house geometries. Two houses were constructed inside a large fire facility. The first of two houses constructed was a one-story, 111.5 m2, 3 bedroom, 1 bathroom house with 8 total rooms. The second house was a two-story 297.3 m2, 4 bedroom, 2.5 bathroom house with 12 total rooms. The second house featured a modern open floor plan, two-story great room and open foyer. Fifteen experiments were conducted varying the ventilation locations and the number of ventilation openings. Ventilation scenarios included ventilating the front door only, opening the front door and a window near and remote from the seat of the fire, opening a window only and ventilating a higher opening in the two-story house. One scenario in each house was conducted in triplicate to examine repeatability. The results of these experiments examine potential occupant tenability and provide knowledge for the fire service for them to examine their horizontal ventilation standard operating procedures and training content. The fire dynamics resulting from ventilation practices such as ventilation near or remote from the seat of the fire and high versus low in relation to the fire are examined. Several other tactical considerations were developed utilizing the data from these experiments to provide specific examples of changes that can be adopted based on a departments current strategies and tactics. Such tactical considerations and a systems approach to fire service tactics should be investigated further.
Beads and Dice in a Genetic Drift Exercise
Authors: Russo Claudia A. M. , Voloch Carolina M. 
Published: August 2012

Abstract
Natural selection driving adaptive changes is a powerful and intuitive explanation for the evolution of the living world around us. Evolution at the molecular level, however, is chiefly ruled by random genetic drift. The idea that an advantageous allele may be lost by chance in a natural population is rather difficult to explore in the classroom. Low-cost and hands-on educational resources are needed to make genetic drift more intuitive among students. In this exercise, we use colored beads and the roll of a die to simulate drift and selection jointly affecting the fate of the genetic variants in an evolving population. Our aim is to teach students that natural selection does not determine but simply influences the fate of advantageous alleles because random genetic drift is always present. We have been using this exercise successfully for over a decade for the Biological Sciences students at the Federal University of Rio de Janeiro.
Darwinism and the Origin of Life
Authors: Peretó Juli , Català Jesús 
Published: August 2012

AbstractHistorically, ideas on the origins of life have been mingled with evolutionary explanations. Darwin avoided discussing the origin of the very first species in public although he acknowledged the possibility that life originated by natural causes. Some of his followers adopted this materialistic position and advocated some sort of spontaneous generation in the distant past. Nevertheless, Pasteur’s experiments were a major obstacle for scientific acceptance of the sudden emergence of life. The scientific study of the origin of life, established in the 1920s, required abandoning the idea of a unique chance event and considering a view of life emerging as the result of a long evolutionary process. At the turn of the twentieth century, some authors adopted non-Darwinian views on the origin of life, exemplified in this paper by the neovitalism of some Catholic scientists. We propose that Darwinism represents a genuine example of an adaptive scientific framework. By recognizing the shift in the features characterizing Darwinism, we can understand its relationship with theories on the origin of life in a non-dogmatic line.
Risk Factors Associated With Incorrect Surgical Counts
Authors: Rowlands Aletha 
Published: August 2012

AbstractIncorrect surgical counts after surgery are a perplexing problem for nurses working in the perioperative environment. To determine factors associated with an incorrect surgical count, this cross‐sectional, correlational study examined explanatory variables (eg, patient and nurse characteristics, intraoperative circumstances, staff involvement) by using data abstracted from perioperative medical records and primary data collected from perioperative nurses. In the final multivariate analysis, six variables were significantly associated with an incorrect surgical count: a higher surgical risk, a lower body mass index, a complicated procedure, an unplanned procedure, an increased number of perioperative personnel involved, and an increased number of specialty teams involved.
Complications of laparoscopic radical prostatectomy–A single institute experience
Authors: Juan Hsu‐Cheng , Yeh Hsin‐Chih , Li Ching‐Chia , Wu Wen‐Jeng , Chou Yii‐Her , Huang Chun‐Hsiung , Huang Shu‐Pin 
Published: August 2012

AbstractLaparoscopic radical prostatectomy (LRP) is a demanding procedure that requires surgical skill, a long learning curve and significant laparoscopic expertise. We report herein our initial experience with 41 laparoscopic radical prostatectomies to assess all perioperative complications in our initial 5‐year experience. We reviewed retrospectively the case records of 41 patients who underwent laparoscopic radical prostatectomy for clinically localized prostate cancer from 2005 to 2010 at our institution. All abnormal symptoms were developed during the 30 days after the operation. Complications were noted as well as their severity according to the Clavien grading system. No conversion to open surgery was necessary in all cases. The median postoperative hospital stay was 10 days (range 9–16). The median duration of bladder catheterization was 8 days (range 7–35). There was no case of multiple‐organ dysfunction or death. Minor complications constituted 82.6% of all complications. The incidence of severe complications was 17.4%. LRP displayed some advantages over open surgery in the perioperative period. Our complication rates were significantly higher than those indicated in the series previously reported. We found that most complications occurred in the first 30 patients who underwent LRP. We suggest that the surgeons should pay more attention to the difficulties of the procedure.
Nonzero azimuthal magnetic fields at the solar source surface: Extraction, model, and implications
Authors: Schulte in den Bäumen Hagen , Cairns Iver H. , Robinson P. A. 
Published: August 2012

A recent two‐dimensional (radial distancer and solar longitude ϕ) model for the solar wind is driven using 1 h average data from the Wind spacecraft. We extend the treatment of the Sun's magnetic field in comparison with previous models to allow a nonzero intrinsic azimuthal component Bϕ at the solar source surface, in addition to the radial component Br. We find nonzero azimuthal magnetic fields at the source surface which dominate the variability in B(r, ϕ) at 1 AU and beyond. The averages 〈|Bϕ(Rs)|〉 and 〈|Br(Rs)|〉 inferred over solar cycle 23 were 0.44 ± 0.48 μT (4.4 ± 4.8 mG) and 120 ± 30 μT (1.2 ± 0.3 G) at the photosphere, respectively, where Rs equals one solar radius. While the surface magnetic field is closely radial on average as expected, it is sometimes over 20° from radial. Both Bϕ and Br vary smoothly on periods of order of a day, with evidence for relatively narrow current sheets, and vary differently with the solar cycle: Br(Rs) is correlated with the sunspot number while Bϕ(Rs) has a two‐level behavior. The typical fields |Br(Rs)| are consistent with previous estimates. This consistency, the finding of a linear relation between the data‐smoothing time period and the average transition time for each component and other arguments support the contention that theBϕ(Rs) fields found are intrinsic. Our results and model can account naturally for non‐Parker‐like magnetic field directions at 1 AU and allr above the source surface.