bluuebunny/crossref_metadata_2025_split huggingface dataset:
Survey of the h index for all of academic neurosurgery: another power-law phenomenon?
Authors: Spearman Christopher M. , Quigley Madeline J. , Quigley Matthew R. , Wilberger Jack E. 
Published: May 2010

Object
The h index is a recently developed bibliometric that assesses an investigator's scientific impact with a single number. It has rapidly gained popularity in the physical and, more recently, medical sciences.

Methods
The h index for all 1120 academic neurosurgeons working at all Electronic Residency Application Service–listed training programs was determined by reference to Google Scholar. A random subset of 100 individuals was investigated in PubMed to determine the total number of publications produced.

Results
The median h index was 9 (range 0–68), with the 75th, 90th, and 95th percentiles being 17, 26, and 36, respectively. The h indices increased significantly with increasing academic rank, with the median for instructors, assistant professors, associate professors, and professors being 2, 5, 10, and 19, respectively (p < 0.0001, Kruskal-Wallis; all groups significantly different from each other except the difference between instructor and assistant professor [Conover]). Departmental chairs had a median h index of 22 (range 3–55) and program directors a median of 17 (range 0–62). Plot of the log of the rank versus h index demonstrated a remarkable linear pattern (R2 = 0.995, p < 0.0001), suggesting that this is a power-law relationship.

Conclusions
A survey of the h index for all of academic neurosurgery is presented. Results can be used for benchmark purposes. The distribution of the h index within an academic population is described for the first time and appears related to the ubiquitous power-law distribution.
Expectations Hypothesis
Authors: Sangvinatsos Antonios 
Published: May 2010

AbstractThe termexpectations hypothesis(EH) stands for numerous statements that link the behavior of short‐term and long‐term interest rates. The literature distinguishes between thepure expectations hypothesis(PEH), which postulates that (i) expected excess returns on long‐term over short‐term bonds are zero, (ii) yield term premia are zero, or (iii) forward term premia are zero, from the EH, which postulates that (i) expected excess returns are constant over time, (ii) yield term premia are constant, or (iii) forward term premia are constant over time. We present all the forms of the PEH in discrete time with discrete and continuous compounding and in continuous time (continuous compounding). We will see that the PEH expressions derived in all these models are not equivalent across models as well as within each model.
Hull–White Stochastic Volatility Model
Authors: Gauthier Pierre , Rivaille Pierre‐Yves H. 
Published: May 2010

AbstractThe Hull–White equity model (1987) is one of the first stochastic volatility models introduced. Introducing mean variance, a closed‐form option pricing formula is derived. Through numerical simulation, the impact of correlation on the volatility smile shape is shown. Hence various smiles can be fitted. However it lacks a mean reverting behaviorá laHeston for capturing the volatility term structure.
Universal Portfolios
Authors: Ordentlich Erik 
Published: May 2010

AbstractThe theory of universal portfolios forgoes the stochastic models and associated optimality criteria of classical portfolio optimization, and instead seeks universal portfolio selection strategies that perform well relative toallstrategies in a target class of allocation strategies, forallpossible sequences of asset price changes. This article reviews the theory as specialized to the target class of constant rebalanced portfolios. In this case, universal portfolios have been found that asymptotically achieve the rate of return of the best constant rebalanced portfolio in hindsight, irrespective of asset price behavior.
Stimuli‐Responsive Porous Hydrogels at Interfaces for Molecular Filtration, Separation, Controlled Release, and Gating in Capsules and Membranes
Authors: Tokarev Ihor , Minko Sergiy 
Published: May 2010

AbstractA continuously growing area of controlled and tunable transport and separation of biomolecules and drugs has recently attracted attention to the structures which can be referred to as stimuli‐responsive porous hydrogel thin films. Because of spatial constraints, swelling/shrinking of the hydrogel films results in closing/opening (or vice versa) of the film's pores. Such responsive systems can be used in the configuration of plane films or capsules. The combination of a low thickness (translating into a low hydrodynamic flow resistance and rapid response) with well‐defined size and shape of pores (translating into better control of transport and separation), which can be closed, opened, or tuned by an external signal (allowing a large amplitude of changes in diffusivity of solutes in the thin film and a precise control of the pore size), makes these materials very attractive for a range of applications, such as molecular filtration, separation, drug delivery, sensors, and actuators.
Novel negatively charged hybrids. 2. Preparation of silica‐based hybrid copolymers and their applications for Cu2+ removal
Authors: Hu Keyan , Liu Junsheng , Wo Hengzhou , Li Tao 
Published: May 2010

AbstractA series of negatively charged silica‐based hybrid copolymers were prepared via free radical polymerization of γ–methacryloxypropyl trimethoxy silane (MAPTMS), 4–vinylbenzylchloride (VBC), and styrene (St) monomers, and the sol–gel process. Their applications for Cu2+ removal from aqueous solution were investigated. TGA and DrTGA thermal analyses indicated that these hybrid copolymers can keep thermally stable up to 412°C. Their cation‐exchange capacities (CIECs) are within the range of 0.49–1.25 mmol g–1. Adsorption experiments indicated that the adsorption followed Langmuir isotherm model, suggesting that it is Langmuir monolayer adsorption. The electrostatic attraction between the ionic groups and Cu2+, the content of ionic groups and the existence of reactive chloromethyl groups might be responsible for such trend. Based on these findings, it can be concluded that the incorporation of VBC in the hybrid copolymers conduces to the advance of Cu2+ adsorption capacity; however, the incorporation of St makes little contribution to the raise of Cu2+ adsorption capacity, suggesting that the adsorption performances of these silica‐based hybrid copolymers can be artificially adjusted and have potentially application in the removal of Cu2+ from wastewater. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Flocking coordination using active leader and local information
Authors: Etemadi Shahram , Alasty Aria , Vossoughi Gholam‐Reza 
Published: May 2010

AbstractIn this paper coordination of a group of agents by a coordinator agent, called the leader‐agent (LA), is discussed. Agents have identical finite sensing radii and access only the local information. Inter‐agent interactions bring them together as a multi‐agent network system. In a recently proposed flocking algorithm using a virtual leader, it is proved that if a fraction of agents are informed then the center of mass of the multi‐agent system tracks the virtual leader. The minimum number of the fraction is always greater than one. In this paper the only informed agent is the LA. Interaction functions are defined to make the model of the multi‐agent system suitable for the design of the coordination control algorithm. The leader‐agent accesses its local data and actively plans its motions through a nonlinear control method. It is proven in this paper that the multi‐agent system tracks the virtual leader and a locally defined point near the LA converges to the position of the virtual leader. It is also shown that in this case, center of mass of the multi‐agent system follows the virtual leader but with a finite distance. We have also discussed positive effects of the LA on network connectivity. Finally illustrative examples are added as well. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Long‐term outcome in localized extranodal mucosa‐associated lymphoid tissue lymphomas treated with radiotherapy
Authors: Goda Jayant S. , Gospodarowicz Mary , Pintilie Melania , Wells Woodrow , Hodgson David C. , Sun Alexander , Crump Micheal , Tsang Richard W. 
Published: May 2010

AbstractBACKGROUND:This study was conducted to evaluate the long‐term outcomes in patients with stage IE and IIE mucosa‐associated lymphoid tissue (MALT) lymphomas treated with involved field radiotherapy (RT).METHODS:Between 1989 and 2004, 192 patients with stage I and II MALT lymphomas were treated. The report focuses on 167 patients who received RT. The median age of patients was 58 years with a female predominance (2:1). Presenting sites were as follows: orbital adnexa in 71 patients, salivary glands in 28 patients, stomach in 25 patients, thyroid in 21 patients, and other sites in 22 patients. The median dose to nonorbital sites was 30 grays (Gy) (range, 17.5‐35 Gy) and was 25 Gy for the orbit (range, 25‐35 Gy). The median follow‐up was 7.4 years (range, 0.67‐16.20 years).RESULTS:Complete response and complete response, unconfirmed (CR/CRu) was noted in 166 (99%) patients. The 10‐year recurrence‐free rate (RFR) was 76%, the disease‐free survival (DFS) rate was 68%, the overall survival (OS) rate was 87%, and the cause‐specific survival rate was 98%. According to presenting site, the 10‐year RFR was 95% for thyroid, 92% for stomach, 68% for salivary glands, and 67% for orbit. Patients with thyroid and gastric MALTs had better outcome compared with patients with MALTs diagnosed at other sites (P = .004). Among those patients who achieved CR, 19% developed disease recurrence (n = 31), chiefly in distant sites or untreated contralateral‐paired organs. At the time of disease recurrence, 7 patients (23%) had transformed to diffuse large B‐cell lymphoma, 2 of whom died of lymphoma. The 5‐year OS rate after treatment failure was 83%.CONCLUSIONS:Patients with localized MALT lymphomas are reported to have excellent clinical outcome after moderate‐dose RT, and some are likely cured. In the current study, thyroid and gastric MALTs were found to have significantly less risk of distant recurrence. Despite disease recurrence, the overall survival remains excellent in these patients. Cancer 2010. © 2010 American Cancer Society.
Reduction of on‐resistance in ion‐implanted GaN/AlGaN/GaN HEMTs with low gate leakage current
Authors: Nomoto Kazuki , Satoh Masataka , Nakamura Tohru 
Published: May 2010

AbstractSi ion‐implanted GaN/AlGaN/GaN HEMTs with extremely low gate leakage current and low source resistance prepared without any recess etching process are demonstrated. The source/drain regions were formed using Si ion implantation into undoped GaN/AlGaN/GaN on a sapphire substrate. After ion implantation into source/drain regions at an energy of 80 keV, the performance was significantly improved. The on‐resistance was reduced from 26.2 to 4.3 Ω‐mm. The saturation drain current and maximum trans‐conductance increased from 284 to 723 mA/mm and from 48 to 147 mS/mm. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(6): 19–24, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10213
A coupled ecohydrological–three‐dimensional unsaturated flow model describing energy, H2O and CO2 fluxes
Authors: Cervarolo G. , Mendicino G. , Senatore A. 
Published: May 2010

AbstractA soil–vegetation–atmosphere‐transfer (SVAT) scheme and a vegetation dynamic model (VDM) have been coupled to a three‐dimensional unsaturated flow model developed in a cellular automata (CA) environment, for reproducing the interactions between vegetation dynamics, subsurface flow processes, and water, energy and CO2 budgets. The performances of the model were verified through Leaf Area Index (LAI), ground energy and CO2 fluxes' measurements recorded by eddy covariance systems in a southern Italian site and in California (USA). The model proved to be a reliable tool for the estimation of CO2, energy and water fluxes, vegetation dynamics, and of the space–time distribution of soil moisture. Furthermore, a sensitivity analysis has been performed on 49 parameters plus five initial conditions, revealing that there are relatively few parameters significantly influencing the main output of the model. The most innovative feature of the model is that it was developed following a discrete approach based on an extension of the original CA computational paradigm, whose structure permits high computational efficiency on parallel architectures to be achieved. This allows the proposed model to be used on wide areas with a highly detailed description of the processes involved, especially the soil water diffusion dynamics, both along the vertical and the horizontal directions. A three‐dimensional test case is proposed with boundary conditions inducing a significant lateral flow. In this case the coupled model showed both the importance of a detailed modelling of the three‐dimensional water diffusion, and its potential in describing the reciprocal influences among soil water flow, water fluxes and CO2 fluxes at the surface in the case of bare soil and growing vegetation. Specifically, in the case of vegetation cover, root activity reduced the propagation of the wet front in the soil, involving percentage differences in soil moisture up to 16% after 15 days simulation. Copyright © 2010 John Wiley & Sons, Ltd.
Amination of Aryl Iodides Using a Fluorous‐Tagged Ammonia Equivalent
Authors: Nielsen Simon Dalsgaard , Smith Garrick , Begtrup Mikael , Kristensen Jesper Langgaard 
Published: May 2010

AbstractA fluorous‐tagged ammonia equivalent for the Cu‐catalyzed amination of aryl iodides is described in which N‐Boc‐protected anilines are produced in high overall yield and purity. All purification steps are performed using Fluorous Solid‐Phase Extraction (F‐SPE) greatly simplifying and speeding up the isolation of the desired products.
Group entitativity and its perceptual antecedents in varieties of groups: A developmental perspective
Authors: Svirydzenka Nadzeya , Sani Fabio , Bennett Mark 
Published: May 2010

AbstractThe present study sought to determine whether children discriminate between different group types with respect to perceived entitativity, and if so, whether the group properties that determine their perceptions of entitativity differ from those of adults. Ten‐year‐old children and adults were required to rate 12 social groups on a number of properties, including entitativity. In a further task, participants also sorted 30 social groups into discrete group types. Two major findings emerged. First, over the two tasks both children and adults were found to classify groups in terms of at least four main group types: Intimacy groups, task groups, social categories and loose associations. Second, children and adults appeared to have different perceptions concerning which group properties determine the degree of entitativity of the different group types. In particular, children put much more emphasis on the level of interaction among group members whereas adults emphasized the importance of the group among its members. Copyright © 2010 John Wiley & Sons, Ltd.
Control of the earthquake and wind dynamic response of steel‐framed buildings by using additional braces and/or viscoelastic dampers
Authors: Mazza Fabio , Vulcano Alfonso 
Published: May 2010

AbstractThe insertion of steel braces equipped with viscoelastic dampers (VEDs) (‘dissipative braces’) is a very effective technique to improve the seismic or wind behaviour of framed buildings. The main purpose of this work is to compare the earthquake and wind dynamic response of steel‐framed buildings with VEDs and achieve optimal properties of dampers and supporting braces. To this end, a numerical investigation is carried out with reference to the steel K‐braced framed structure of a 15‐storey office building, which is designed according to the provisions of Eurocodes 1 and 3, and to four structures derived from the first one by the insertion of additional diagonal braces and/or VEDs. With regard to the VEDs, the following cases are examined: absence of dampers; insertion of dampers supported by the existing K‐braces in each of the structures with or without additional diagonal braces; insertion of dampers supported by additional diagonal braces. Dynamic analyses are carried out in the time domain using a step‐by‐step initial stress‐like iterative procedure. For this purpose, the frame members and the VEDs are idealized, respectively, by a bilinear model, which allows the simulation of the nonlinear behaviour under seismic loads, and a six‐element generalized model, which can be considered as an in‐parallel‐combination of two Maxwell models and one Kelvin model. Artificially generated accelerograms, whose response spectra match those adopted by Eurocode 8 for a medium subsoil class and for different levels of peak ground acceleration, are considered to simulate seismic loads. Along‐wind loads are considered assuming, at each storey, time histories of the wind velocity for a return period Tr=5 years, according to an equivalent spectrum technique. Copyright © 2010 John Wiley & Sons, Ltd.
Influence of the mean period of ground motion on the inelastic dynamic response of single and multi degree of freedom systems
Authors: Kumar M. , Castro J. M. , Stafford P. J. , Elghazouli A. Y. 
Published: May 2010

AbstractThis paper focuses on examining the effects of frequency content of the ground motion on the inelastic demands imposed on both single degree of freedom (SDF) and multi degree of freedom (MDF) steel‐framed systems. A detailed literature review is conducted to identify the indicator that best represents the frequency content of ground motion. The mean period (Tm) of ground motion is selected owing to its ability to distinguish between various spectral shapes of ground motion, and its relationship with magnitude, distance and site characteristics. Inelastic displacement demands on SDF systems for target ductility levels are first studied in the light of Tm, using a suite of 128 ground motion records. The study is then extended to MDF systems with the help of incremental dynamic analysis by employing the same ground motion ensemble to assess the influence of Tm on various engineering demand parameters. The results obtained indicate that, for SDF systems, the amplification of displacements occurs when the period ratio between elastic period (Te) and Tm is lower than unity. For MDF systems, the results demonstrate that the influence of higher modes on the base shear and maximum storey drift profile becomes more pronounced, as Tm approaches the higher mode periods of the structure. These observations, for both SDF and MDF systems, tend to be more evident for higher levels of inelasticity. The significance of the results, with particular reference to European seismic design procedures, is highlighted. Copyright © 2010 John Wiley & Sons, Ltd.
Rosenbrock‐based algorithms and subcycling strategies for real‐time nonlinear substructure testing
Authors: Bursi O. S. , Jia C. , Vulcan L. , Neild S. A. , Wagg D. J. 
Published: May 2010

AbstractIn this paper, Rosenbrock‐based algorithms originally developed for real‐time testing of linear systems with dynamic substructuring are extended for use on nonlinear systems. With this objective in mind and for minimal overhead, both two‐ and three‐stages linearly implicit real‐time compatible algorithms were endowed with the Jacobian matrices requiring only one evaluation at the beginning of each time step. Moreover, these algorithms were improved with subcycling strategies. In detail, the paper briefly introduces Rosenbrock‐based L‐Stable Real‐Time (LSRT) algorithms together with linearly implicit and explicit structural integrators, which are now commonly used to perform real‐time tests. Then, the LSRT algorithms are analysed in terms of linearized stability with reference to an emulated spring pendulum, which was chosen as a nonlinear test problem, because it is able to exhibit a large and relatively slow nonlinear circular motion coupled to an axial motion that can be set to be stiff. The accuracy analysis on this system was performed for all the algorithms described. Following this, a coupled spring‐pendulum example typical of real‐time testing is analysed with respect to both stability and accuracy issues. Finally, the results of representative numerical simulations and real‐time substructure tests, considering nonlinearities both in the numerical and the physical substructure, are explored. These tests were used to demonstrate how the LSRT algorithms can be used for substructuring tests with strongly nonlinear components. Copyright © 2010 John Wiley & Sons, Ltd.
Wind erosion characteristics of Sahelian surface types
Authors: Maurer Thomas , Herrmann Ludger , Stahr Karl 
Published: May 2010

AbstractThe assessment of wind erosion magnitudes for a given area requires knowledge of wind erosion susceptibilities of the dominant local surface types. Relative wind erosion potentials of surfaces can hardly be compared under field conditions, as each erosion event is unique in terms of duration, intensity and extent.The objective of this study was to determine and compare relative wind erosion potentials of the most representative surface types over a transect comprising most parts of southwestern Niger. For this purpose, mobile wind tunnel experiments were run on 26 dominant surface types. The effects of surface disturbance were additionally determined for 13 of these surfaces. The results, namely measurements of wind fields and mass fluxes, can be classified according to specific surface characteristics.Three basic surface groups with similar emission behaviour and aerodynamic characteristics were identified: (1) sand surfaces, (2) rough stone surfaces and (3) flat crusted surfaces. Sand surfaces feature a turbulent zone close to the surface due to the development of a saltation layer. Their surface roughness is medium to high, as a consequence of the loss of kinetic energy of the wind field to saltating particles. Sand surfaces show the highest mass fluxes due to the abundance of loose particles, but also fairly high PM10 fluxes, as potential dust particles are not contained in stable crusts or aggregates. Rough stone surfaces, due to their fragmented and irregular surface, feature the highest surface roughness and the most intense turbulence. They are among the weakest emitters but, due to their relatively high share of potential dust particles, PM10 emissions are still average. Flat crusted surfaces, in contrast, show low turbulence and the lowest surface roughness. This group of surfaces shows rather heterogeneous mass fluxes, which range from moderate to almost zero, although the share of PM10 particles is always relatively high. Topsoil disturbance always results in higher total and PM10 emissions on sand surfaces and also on flat crusted surfaces. Stone surfaces regularly exhibit a decrease in emission after disturbance, which can possibly be attributed to a reorganization which protects finer particles from entrainment.The results are comparable with field studies of natural erosion events and similar wind tunnel field campaigns. The broad range of tested surfaces and the standardized methodology are a precondition for the future regionalization of the experimental point data. Copyright © 2010 John Wiley & Sons, Ltd.