bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrochemical copolymerization and stability of crosslinked bis[1,2‐(pyrrol)ethoxy]ethane with pyrrole
Authors: Wang Min , Zhang Hanchang , Bai Ruke , Ge Xueping 
Published: May 2008

AbstractThe copolymers, pyrrole‐co‐bis[1,2‐(pyrrol)ethoxy]ethane (PEE), were produced by electropolymerization in acetonitrile (containing 0.1 mol L−1lithium perchlorate). The properties and morphology of these polymers were investigated by cyclic voltammetry, UV–vis absorption spectra and scanning electron microscopy (SEM), respectively. The results exhibit that the cyclic voltammograms and rates of electropolymerization of the prepared copolymers were significantly affected by PEE concentration in water and acetonitrile solution. Higher applied potential was required for the polymerization with decreasing the ratio of pyrrole/PEE. This was ascribed to the steric hindrance of high concentration of N‐substituted groups. The SEM images of the poly(pyrrole‐co‐PEE) and PPEE films show more compact and more smooth morphology compared with that of PPy and cyclic voltammogram of the poly(pyrrole‐co‐PEE) films, which display good electrochemical stability in the mixed solution, indicating that the modification of crosslinked structure was effective for the stabilization of the redox cycles. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Ferromagnetic nanoparticles embedded in self‐arranged matrices
Authors: Rumpf K. , Granitzer P. , Pölt P. , Šimić S. , Krenn H. 
Published: May 2008

AbstractThe investigated nanoscopic system, consisting of a non magnetic host material and precipitated ferromagnetic nanostructures shows a magnetic behaviour correlated to the size and shape of the deposited particles but also to their spatial distribution within the template which modifies the magnetic interactions between them. The nanostructures are deposited electrochemically into an etched silicon wafer exhibiting an array of channels of a few ten nanometers in diameter and a length up to 50 µm. The self‐assembled grown templates offer the opportunity of tuning the magnetic properties by varying the geometrical characteristics of the membrane which can be loaded with different metals like Ni or Co with variable metal distribution. Magnetic characteristics like coercivity, magnetic anisotropy and temperature dependent magnetization give a survey about the structure and the magnetic interactions of the nanocomposite. This achieved ferromagnetic nanocomposite system is not only of interest for basic research but also gives rise to applications in magneto‐optics, spintronics and sensor application. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermal oxidation of few‐layer graphite plates: an SPM study
Authors: Osváth Z. , Nemes‐Incze P. , Tapasztó L. , Horváth Z. E. , Biró L. P. 
Published: May 2008

AbstractCommercial few‐layer graphite platelets were characterized by atomic force microscopy (AFM). Successive oxidation of the graphite platelets was carried out at 450–550 °C in air, and AFM measurements were performed after each oxidation step. The measurements showed that the applied thermal oxidation reduced the dimensions of the platelets. We have also observed the spontaneous assembly of the few‐layers thick platelets into a macroscopic, free‐standing film. Portions of this free‐standing graphite film were investigated by AFM and scanning tunneling microscopy (STM). (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The case for MR‐compatible robotics: a review of the state of the art
Authors: Elhawary Haytham , Tse Zion Tsz Ho , Hamed Abbi , Rea Marc , Davies Brian L. , Lamperth Michael U. 
Published: May 2008

AbstractBackgroundThe numerous imaging capabilities of magnetic resonance imaging (MRI) coupled with its lack of ionizing radiation has made it a desirable modality for real‐time guidance of interventional procedures. The combination of these abilities with the advantages granted by robotic systems to perform accurate and precise positioning of tools has driven the recent development of MR‐compatible interventional and assistive devices.MethodsThe challenges in this field are presented, including the selection of suitable materials, actuators and sensors in the intense magnetic fields of the MR environment.ResultsOnly a small number of developed systems have made it to the clinical level (only two have become commercial ventures), showing that the field has not yet reached maturity.ConclusionsA brief overview of the current state of the art is given, along with a description of the main opportunities, possibilities and challenges that the future will bring to this exciting and promising field. Copyright © 2008 John Wiley & Sons, Ltd.
An interregional system dynamics model of animal disease control: applications to foot‐and‐mouth disease in the Southern Cone of South America
Authors: Rich Karl M. 
Published: May 2008

AbstractFoot‐and‐mouth disease (FMD) is costly for meat producers, given its ability to rapidly spread over space, with control efforts in one region crucially depending on the control efforts undertaken in other regions. This paper presents a model of FMD control that applies system dynamics to the spatial spread of disease among South American countries with traditionally different control regimes and assesses the impact of alternative control strategies. Model results demonstrate that preventative vaccination led to shorter outbreaks (by over 2 weeks) than other strategies, though the resources required to implement this may be difficult to mobilize. The model also shows that a combination of region‐specific policies often controls disease better than uniform region‐wide approaches, suggesting the need for improved multinational coordination of disease control. Copyright © 2008 John Wiley & Sons, Ltd.
Steering without Circe: attending to reinforcing loops in social systems
Authors: Lane David C. , Husemann Elke 
Published: May 2008

AbstractRelating system dynamics to the broad systems movement, the key notion is that reinforcing loops deserve no less attention than balancing loops. Three specific propositions follow. First, since reinforcing loops arise in surprising places, investigations of complex systems must consider their possible existence and potential impact. Second, because the strength of reinforcing loops can be misinferred—we include an example from the field of servomechanisms—computer simulation can be essential. Be it project management, corporate growth or inventory oscillation, simulation helps to assess consequences of reinforcing loops and options for interventions. Third, in social systems the consequences of reinforcing loops are not inevitable. Examples concerning “globalization” illustrate how difficult it might be to challenge such assumptions. However, system dynamics and ideas from contemporary social theory help to show that even the most complex social systems are, in principle, subject to human influence. In conclusion, by employing these ideas, by attending to reinforcing as well as balancing loops, system dynamics work can improve the understanding of social systems and illuminate our choices when attempting to steer them. Copyright © 2008 John Wiley & Sons, Ltd.
High‐rate preparation of thin Si films by atmospheric‐pressure plasma enhanced chemical transport
Authors: Kamada Daiki , Kishimoto Kazuya , Kakiuchi Hiroaki , Yasutake Kiyoshi , Ohmi Hiromasa 
Published: May 2008

AbstractPolycrystalline Si films were prepared by chemical transport using near‐atmospheric‐pressure pure hydrogen plasma (6.7 × 10−3 to 5.3 × 10−2 MPa). Substrate temperatures were varied from 200 to 600 °C and solid Si source was used as the feedstock to generate SiHx species. To generate high‐density stable glow hydrogen plasma at near atmospheric pressure, 150 MHz very high frequency (VHF) power was used. The dependence of deposition rate on various preparation parameters, such as VHF input power, hydrogen pressure, and substrate temperature, was investigated. The deposition rate increased with increasing VHF power density and substrate temperature. The attained deposition rate on glass substrates was 15 nm/s at 400 °C. Prepared Si films exhibited columnar structures along the growth direction. The maximum lateral grain size was 5 µm at the film thickness of 15 µm. It was found by Raman spectroscopy that the crystalline fraction of prepared Si film would not be influenced with increasing deposition rate (Rd). Copyright © 2008 John Wiley & Sons, Ltd.
Optimizing the design of clinical trials where the outcome is a rate. Can estimating a baseline rate in a run‐in period increase efficiency?
Authors: Frost Chris , Kenward Michael G. , Fox Nick C. 
Published: May 2008

AbstractIt is well known that the statistical power of randomized controlled trials with a continuous outcome can be increased by using a pre‐randomization baseline measure of the outcome variable as a covariate in the analysis. For a trial where the outcome measure is a rate, for example in a therapeutic trial in Alzheimer's disease, the relevant covariate is a pre‐randomization measure of that rate. Obtaining this requires separating the total follow‐up period into two periods. In the first ‘run‐in’ period all patients would be ‘off‐treatment’ to facilitate the calculation of baseline atrophy rates. In the second ‘on‐treatment’ period half of the patients, selected at random, would be switched onto active treatment with the others remaining off treatment. In this paper we use linear mixed models to establish a methodological framework that is then used to assess the extent to which such designs can increase statistical power. We illustrate our methodology with two examples. The first is a design with three evenly spaced time points analysed with a standard random slopes model. The second is a model for repeated ‘direct’ measures of changes used for the analysis of imaging studies with visits at multiple time points. We show that run‐in designs can materially reduce sample size provided that true between‐subject variability in rates is large relative to measurement error. Copyright © 2008 John Wiley & Sons, Ltd.
A note on tree gatekeeping procedures in clinical trials
Authors: Dmitrienko Alex , Tamhane Ajit C. , Liu Lingyun , Wiens Brian L. 
Published: May 2008

AbstractDmitrienko et al. (Statist. Med. 2007; 26:2465–2478) proposed a tree gatekeeping procedure for testing logically related hypotheses in hierarchically ordered families, which uses weighted Bonferroni tests for all intersection hypotheses in a closure method by Marcus et al. (Biometrika 1976; 63:655–660). An algorithm was given to assign weights to the hypotheses for every intersection. The purpose of this note is to show that any weight assignment algorithm that satisfies a set of sufficient conditions can be used in this procedure to guarantee gatekeeping and independence properties. The algorithm used in Dmitrienko et al. (Statist. Med. 2007; 26:2465–2478) may fail to meet one of the conditions, namely monotonicity of weights, which may cause it to violate the gatekeeping property. An example is given to illustrate this phenomenon. A modification of the algorithm is shown to rectify this problem. Copyright © 2008 John Wiley & Sons, Ltd.
Applicability of MiniPal 4 compact EDXRF spectrometer for soil and sediment analysis
Authors: Oreščanin Višnja , Mikelić Ivanka Lovrenčić , Mikelić Luka , Lulić Stipe 
Published: May 2008

AbstractOptimum measurement parameters for analysis of soil and sediment samples with the compact MiniPal 4 (MP4)EDXRF spectrometer (PANalytical, Almelo, The Netherlands) were presented. The following elements were considered: K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As and Pb. Since the elements from low Z to medium Z region were covered, three measurement conditions (sequences) were defined. The following parameters were selected for measurement of the elements K, Ti, and V: voltage = 12 kV; current = 750 µA; filter material: Al_thin. Cr, Mn and Fe were measured at 20 kV; 300 µA with Al filter while for measurements of Ni, Cu, Zn, As, Pb, Rb, and Sr an Ag filter was selected and tube voltage and current were 30 kV and 300 µA. Each sequence was measured for 200 s and measurements were done in the air. MP4 spectrometer was characterized with acceptable precision, long‐term stability and satisfactory minimum detection limit for the analyses of soil and sediment materials. For the elements K, Mn, Fe, and Ti the precision of the analysis was better than 0.5% and for all the other elements better than 5%. Detection limits for sediment samples were 20 ppm for K, 6.1 ppm for Ti, 5.2 for Mn, 4 ppm for Fe, 4.2 ppm for As and less than 2 ppm for all the other elements. These values were significantly lower compared to typical concentrations of the same elements found in unpolluted soil and sediments. Copyright © 2008 John Wiley & Sons, Ltd.
X‐ray spectrometry: a powerful tool for the measurement of complete fusion of weakly bound nuclei
Authors: Gomes P. R. S. , Padron I. , Capurro O. A. , Niello J. O. Fernández , Martí G. V. , Pacheco A. J. , Arazi A. , Lubian J. , Crema E. 
Published: May 2008

AbstractWe describe how the method of detection of delayed K x‐rays produced by the electron capture decay of the residual nuclei can be a powerful tool in the investigation of the effect of the breakup process on the complete fusion (CF) cross‐section of weakly bound nuclei at energies close to the Coulomb barrier. This is presently one of the most interesting subjects under investigation in the field of low‐energy nuclear reactions, and the difficult experimental task of separating CF from the incomplete fusion (ICF) of one of the breakup fragments can be achieved by the x‐ray spectrometry method. We present results for the fusion of the 9Be + 144Sm system. Copyright © 2008 John Wiley & Sons, Ltd.
Early Elevation of Intra‐Abdominal Pressure After Laparotomy for Secondary Peritonitis: A Predictor of Relaparotomy?
Authors: Basu Adhish , Pai Dinker R. 
Published: May 2008

AbstractBackgroundPatients with secondary peritonitis often require relaparotomy; however, there is no consensus about the criteria for selecting patients who would benefit from early relaparotomy. Our goal was to evaluate whether elevated intra‐abdominal pressure (IAP) during the early postoperative period could predict the need for relaparotomy.MethodsA total of 102 consecutive adult patients with acute intra‐abdominal conditions were admitted for laparotomy. Seventy‐eight patients, who were diagnosed with secondary peritonitis at index surgery, underwent serial measurements of IAP. The primary outcomes measured in the study were incidence of postoperative peritonitis and mortality.ResultsThirty‐two of 78 patients with secondary peritonitis (41%) developed elevated IAP postoperatively. Sixteen (20.5%) of 78 patients developed postoperative peritonitis. Twelve of these 16 patients (75%) with postoperative peritonitis had significantly elevated IAP (P = 0.002) during the immediate postoperative period. Regression analysis revealed elevated IAP (P = 0.055) to be third most predictive of postoperative peritonitis in patients who underwent laparotomy for secondary peritonitis, after septic shock at admission (P = 0.012) and POSSUM score (P = 0.018).ConclusionOur study shows that development of elevated IAP during the early postoperative period can increase the risk of postoperative peritonitis. IAP measured during the immediate postoperative period can be used as a predictor of early relaparotomy.
From Hell to Paradise? Voluntary Transfer of Convicts to the Andaman Islands, 1921–1940
Authors: SHERMAN TAYLOR C. 
Published: May 2008

AbstractThe paper attempts to understand the challenges and opportunities which the penal settlement at Port Blair in the Andaman Islands presented to colonial governments in twentieth-century India. To this end, the paper examines a scheme drawn up in the 1920s which saw the introduction of a much more liberal regime for convicts in Port Blair. Under these plans, convicts were granted access to land and encouraged to bring their families from the mainland. This research reveals that the policies which determined the history of the settlement in this period were defined by two tensions. First, there was a constant battle between the central authorities and provincial governments over the shape and purposes of the settlement. Second, there was a contradiction between the penal objectives of the colony and the larger strategies which aimed to develop the islands for the greater British empire.
Tracial Rokhlin property for automorphisms on simple -algebras
Authors: LIN HUAXIN , OSAKA HIROYUKI 
Published: May 2008

AbstractLetAbe a unital simple$A\mathbb {T}$-algebra of real rank zero. Given an isomorphismγ1:K1(A)→K1(A), we show that there is an automorphismα:A→Asuch thatα*1=γ1andαhas the tracial Rokhlin property. Consequently, the crossed product$A\rtimes _{\alpha }\mathbb {Z}$is a simple unital AH-algebra with real rank zero. We also show that automorphisms with the Rokhlin property can be constructed from minimal homeomorphisms on a connected compact metric space.
Singular perturbation of symbolic dynamics via thermodynamic formalism
Authors: MORITA TAKEHIKO , TANAKA HARUYOSHI 
Published: May 2008

AbstractWe consider singular perturbation of a mixing subshift of finite type by means of thermodynamic formalism. In our formulation, the perturbed systems are described by a family of potentials {Φ(α,⋅)} with large parameter α on a fixed subshift of finite type, and the original (unperturbed) system is characterized as the system at infinity obtained by collapsing the perturbed system upon taking $\alpha \to \infty $. We apply our formulation to the collapse of cookie-cutter systems and dispersing open billiards.
High-resolution trends of nutrients, DOM and nitrogen uptake in the annual sea ice at Terra Nova Bay, Ross Sea
Authors: Cozzi Stefano 
Published: May 2008

AbstractHigh-resolution trends of nutrients and DOM are analysed, with respect to nitrate and ammonium uptakes, in two coastal stations placed on the annual land-fast ice at Terra Nova Bay. The highest accumulations of dissolved inorganic nitrogen (87.2 µmol N dm-3), reactive phosphorus (14.1 µmol P dm-3) and reactive silicon (22.9 µmol Si dm-3) were observed in the bottom ice, although this process was preceded by a nutrient decrease in an interior sea ice layer. In the upper layer of sea ice, DOM was rather constant in concentration and P-deficient (C:N:P = 377:34:1–579:53:1). In the bottom and platelet ice, the accumulation of DOM (1277 µmol C dm-3; 108.2 µmol N dm-3; 7.67 µmol P dm-3) occurred with lower C:N:P ratios (123:14:1–59:7:1), because of a major contribution of fresher organic matter. Nitrate (< 7.33 µmol N dm-3 d-1) and ammonium (< 2.85 µmol N dm-3 d-1) uptakes in the bottom ice were higher than in the platelet ice. The comparison between the data of N-uptake and the concomitant release of total dissolved nitrogen in the bottom ice indicated that the microbial community may be subjected to low growths in situ and high releases of dissolved nitrogen, when it accumulates in this sea ice habitat.
Viral antibodies in south polar skuas around Davis Station, Antarctica
Authors: Miller Gary D. , Watts Joanne M. , Shellam Geoffrey R. 
Published: May 2008

AbstractWe surveyed south polar skuas (Catharacta maccormickiSaunders) in Antarctica for antibodies to a series of viral agents using blood serum and cloacal swabs from 124 adult skuas. There were no ticks on the subjects and we were unable to isolate virus from any individual. Skuas, however, were seropositive to some avian viruses: 16.9% (20/118) had antibodies to infectious bursal disease virus and 10.5% (11/105) were seropositive for Newcastle disease. We found 1.0% (1/98) had antibodies to avian influenza, no evidence of egg drop syndrome (0/48), but 27.8% (10/36) had antibodies to flaviviruses. Clearly south polar skuas encounter a variety of pathogens either in Antarctica or during their migration in the non-breeding season. There was no evidence of disease in skuas, but the presence of antibodies to pathogens indicates the need to continue to search for the origins of these immunological challenges.
Age, geographical distribution and taphonomy of an unusual occurrence of mummified crabeater seals on James Ross Island, Antarctic Peninsula
Authors: Nelson A.E. , Smellie J.L. , Williams M. , Moreton S. 
Published: May 2008

AbstractAn unusually dense collection of some 150 dead crabeater seals (Family Phocidae), in various stages of decay, occurs in the Brandy Bay hinterland, north-western James Ross Island, northern Antarctic Peninsula. Throughout the past 100 years, the presence of shelf ice (no longer present today) and sea ice in Prince Gustav Channel, between James Ross Island and the Antarctic Peninsula, has prevented seals from readily accessing the western side of James Ross Island. However, open water pools, some over one kilometre in diameter, remain accessible throughout the winter months, allowing seals to haul out onto the ice. It is likely that some of these seals may become disorientated as they wander away from the pools and instead head toward Brandy Bay and onto low-lying and snow-covered Abernethy Flats, easily mistaken for sea ice in early winter, where they perish. The large number of variably-decayed animals present suggests that this has probably happened on numerous occasions. However, some of the dead seals also probably perished during a documented mass dying event of crabeater seals in Prince Gustav Channel caused by an unidentified epidemic, possibly phocine distemper virus (PDV), during the spring of 1955.
Characterization of Cold Spray Titanium Deposits by X-Ray Microscopy and Microtomography
Authors: Zahiri Saden H. , Mayo, Sheridan C. , Jahedi Mahnaz 
Published: May 2008

AbstractCold gas dynamic spray (cold spray) is a rapid deposition technology in which particles deposit at velocities above the speed of sound (∼340 ms−1). Generally, porosity forms in cold spray deposits due to insufficient deformation of particles. In this study, the unique capability of the X-ray microscopy and microtomography is utilized to visualize the internal structure of deposited material. The results show that this characterization technique successfully reveals porosities in the cold spray commercial purity (CP) titanium structure. Furthermore, microtomography images confirmed the experimental results for porosity measurements in which helium (compared with nitrogen) as carrier gas significantly decreases porosity in cold spray CP titanium.