bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analytical and Chebyshev pseudospectral numerical solutions for a class of axisymmetric horizontal flows dominated by mass or heat sources
Authors: Mohammadian M. , Charron M. 
Published: December 2011

SUMMARYA class of axisymmetric horizontal flows dominated by strong heat or mass sources are considered here, which systematically arise in multiscale atmospheric and oceanic flows in various spatiotemporal scales such as hurricane embryos. Various linear and nonlinear analytical solutions are proposed, and several examples are given to illustrate them. On the basis of the proposed exact solutions, stability of the flow under various conditions is examined. The proposed exact solutions serve as benchmarks for validation of numerical models. A Chebyshev pseudospectral model is also developed for these flows. The numerical results are compared with the developed analytical solutions as well as a high‐resolution numerical solution, which showed an excellent performance of the numerical model in terms of numerical diffusion and oscillation. The numerical method is also efficient because expensive calculations such as LU decomposition are only needed once, at the beginning of calculations. The model could be used in studying small‐scale and multiple‐scale phenomena such as hot towers and hurricane embryos, which are the subject of future studies. Copyright © 2011 John Wiley & Sons, Ltd.
A new mechanism of oxidation in ultrahigh molecular weight polyethylene caused by squalene absorption
Authors: Oral Ebru , Ghali Bassem W. , Neils Andrew , Muratoglu Orhun K. 
Published: December 2011

AbstractAlthough synovial fluid lipids were found to absorb in ultrahigh molecular weight polyethylene (UHMWPE) total joint implants in vivo, their effect on the oxidation of the polymer was not known. Current understanding of the oxidation and oxidative stability of UHMWPE joint implants is focused on the presence or elimination of radiation‐induced free radicals, which are long‐lived and can react with oxygen over the long term. Recently, we found unexplained oxidation in irradiated and melted UHMWPE components that were exposed to bodily fluids then stored on the shelf despite being free of detectable free radicals at the time of implantation. Thus, we hypothesized that lipids absorbed from the synovial fluid in vivo could initiate and accelerate oxidation of UHMWPE even in the absence of detectable residual free radicals. We found that squalene, a precursor in cholesterol synthesis and a synovial fluid lipid with unsaturated bonds, accelerated oxidation in irradiated and melted UHMWPE under in vitro accelerated aging conditions. This result represents a paradigm shift in our understanding of oxidative stability of UHMWPE and prompts further investigation of in vivo oxidation mechanisms as well as the development of relevant in vitro aging models. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Hunting goodwill: Personal goodwill as property in corporate acquisitions
Authors: Bean LuAnn 
Published: December 2011

AbstractIn today's economy, it's more important than ever to examine the tax planning strategies for any corporate acquisition. Poor tax planning for goodwill acquired in an unwise acquisition can lead to a loss in value overnight! And if that happens, a company may have to write it off against earnings. In the worst case, a company might have to write off most, if not all, of its goodwill.So as more acquisitions of closely held entities occur, it's increasingly important to separate the intangible value of a company into enterprise goodwill versus personal goodwill. But it's a difficult challenge. What techniques or strategies will help?This article has some answers. The author reveals the importance of the treatment of personal goodwill versus enterprise goodwill—for both the seller and the buyer. And the author also examines factors that should be considered when structuring such an acquisition. © 2012 Wiley Periodicals, Inc.
Duration of venous thromboembolism risk across a continuum in medically ill hospitalized patients
Authors: Amin Alpesh N. , Varker Helen , Princic Nicole , Lin Jay , Thompson Stephen , Johnston Stephen 
Published: December 2011

AbstractBACKGROUND:Patients hospitalized for medical illness are at increased risk of venous thromboembolism (VTE), but the duration of risk is not well understood.OBJECTIVE:To assess incidence and time course of symptomatic VTE following hospitalization for medical illness in a large, real‐world patient population.DESIGN:Data were extracted from the Thomson Reuters MarketScan® Inpatient Drug Link File.PATIENTS:Those hospitalized with cancer, heart failure, severe lung disease, or infectious disease from 2005 to 2008.MEASUREMENTS:The cumulative VTE risk over 180 days after admission was calculated using Kaplan‐Meier analysis. VTE hazard was calculated on a daily basis and smoothed through LOESS regression.RESULTS:The analysis included 11,139 medically ill patients, 46.7% and 8.8% of whom received pharmacological thromboprophylaxis during hospitalization and after discharge, respectively. The mean duration of prophylaxis during hospitalization was 5.0 days. Of the 11,139 patients, 366 (3.3%) experienced a symptomatic VTE event. VTE events were most frequent during days 0‐9 (97 events), followed by days 10‐19 (82 events). The mean length of hospital stay was 5.3 days, and 56.6% of all VTE events occurred after discharge. VTE hazard peaked at day 8, with 1.05 events per 1000 person‐days.CONCLUSIONS:The time course of VTE in medical patients shows that risk of symptomatic VTE is highest during the first 19 days after hospital admission, and extends into the period after discharge. Future research is warranted to investigate risks and benefits of reducing the incidence of VTE after discharge, including the role of improving thromboprophylaxis practices in the inpatient setting and extending thromboprophylaxis after hospitalization. Journal of Hospital Medicine 2012;. © 2011 Society of Hospital Medicine
Why surgeons can say “No”: Exploring “Unilateral Withholding”
Authors: Manthous Constantine A. , Ivy Michael 
Published: December 2011

AbstractOBJECTIVE:To explore why it is permissible for surgeons to “unilaterally withhold” surgery, whereas it is not commonplace (in the United States) to unilaterally withhold cardiopulmonary resuscitation (CPR) for clinical situations with similar degrees of uncertainty and prognosis.DATA SOURCES:The medical literature was sampled using PubMed and Google search engines, employing a variety of search strategies to capture articles relating to medical/surgical decision‐making, risk aversion, acute care surgery, and withholding life‐saving therapies. These topics are used to highlight interprovider variability that affects all practitioners—not just surgeons—and to consider why we deem it permissible for surgeons to withhold surgery, whereas—in the United States, at least—it is not routinely permissible for clinicians to unilaterally withhold mechanical ventilation and CPR for cases with similar prognoses.CONCLUSIONS:While there are no published research studies that deal directly with this topic, knowledge, heuristics, experience, variable aversion to risk, and other features inherent in medical‐surgical education likely impact decisions to offer or withhold potentially life‐saving therapies of all kinds. Both surgeons and clinicians, who request surgical consultation for hospitalized patients, should consider these issues and politely pursue second opinions when there is any doubt whether forgoing surgery is in the patient's best interests. Similarly, while unilateral withholding of CPR is not commonly employed in some medical cultures, including the United States, beneficence can be facilitated through robust informed consent. Journal of Hospital Medicine 2012; © 2011 Society of Hospital Medicine
A multi‐sensor study of water vapour from radiosonde, MODIS and AERONET: a case study of Hong Kong
Authors: Liu Zhizhao , Wong Man Sing , Nichol Janet , Chan P. W. 
Published: December 2011

AbstractWater vapour is one of green house gases (GHG) and a key parameter affecting weather forecasting. Situated on the edge of the South China Sea and in the path of the wet Asian monsoon, Hong Kong experiences more rainstorms than most other cities. An accurate observation of water vapour has a special significance in severe weather prediction for Hong Kong, one of the cities with the highest density of population in the world. In this paper, water vapour observations over the last 6 years from an AErosol RObotic NETwork (AERONET) sunphotometer, 9 years from the MODerate resolution Imaging Spectroradiometer (MODIS) TERRA satellite images and 38 years from radiosonde were analysed and cross‐validated. The operational MODIS water vapour products, namely MOD05 and MOD07, with a spatial resolution of 1 and 5 km, respectively, were compared with both radiosonde and AERONET data. The correlation coefficients between MODIS water vapour products and radiosonde data are r = 0.878 and 0.876 for MOD05 and MOD07 products, and the correlations of those with AERONET data are r = 0.822, r = 0.976, respectively. The results also indicate that radiosonde and AERONET water vapour observations have a good agreement, with a correlation of r = 0.988 and a small mean absolute difference (MAD), and root mean square error (RMS) of 0.197 and 0.289 cm, respectively. Although the satellite data (with a frequency of once per day) represent water vapour coverage of all the territories of Hong Kong, they do not meet short‐term weather prediction demand due to their low temporal resolution. Radiosonde observations with a frequency of twice per day are also temporally inadequate. This study demonstrates that the AERONET sunphotometer can provide accurate and high temporal resolution water vapour data which can be used for short‐term weather prediction and long‐term climate change research. Copyright © 2011 Royal Meteorological Society
Perturbation Theory of Polymer Chains Revisited, 2—Intermolecular Excluded Volume of Random and Self‐Avoiding Walks
Authors: Zifferer Gerhard , Olaj Oskar Friedrich 
Published: December 2011

AbstractThe intermolecular compatibility of 107–108 independent pair configurations of linear chains (chain length 64 ≤ N ≤ 8192) with and without intramolecular interaction on various lattices is checked and the intermolecular excluded volume u evaluated. From the (average) number of possible i‐tuples of overlaps in the pair configurations the parameters Ck of the perturbation theory are calculated. Differences between the various lattice types at finite N vanish completely for N → ∞. While the theoretical values of C1 and C2 were recovered within very narrow limits for chains without intramolecular interaction, markedly higher figures apply to self‐avoiding walks. The excluded volume u itself and higher Ck parameters are called upon to test several classical and renormalized perturbation theories.magnified image
Efficient sampling of early signal arrival for estimation of perfusion and transit time in whole‐brain arterial spin labeling
Authors: Lee Wayne , Janik Rafal , Scouten Amy , Stefanovic Bojana , Sled John G. 
Published: December 2011

AbstractArterial spin labeling can be used to measure both cerebral perfusion and arterial transit time. However, accurate estimation of these parameters requires adequate temporal sampling of the arterial spin labeling difference signal. In whole‐brain multislice acquisitions, two factors reduce the accuracy of the parameter estimates: saturation of labeled blood in transit and inadequate sampling of early difference signal in superior slices. Label saturation arises when slices are acquired inferior‐to‐superior such that slice selection in proximal slices spoils the label for a distal slice. Inadequate sampling arises when the time spent acquiring inferior slices is too long to allow early sampling of the difference signal in superior slices. A novel approach to multislice imaging is proposed to address these two issues. In round‐robin arterial spin labeling, slices are acquired in a different order after every pair of control‐label acquisitions. Round‐robin arterial spin labeling enables the acquisitions of all slices across the same range of postlabel delays in a descending superior‐to‐inferior order. This eliminates the temporal sampling problem and greatly reduces label saturation. Arterial transit time estimates obtained for the whole brain with round‐robin arterial spin labeling show better agreement with a single‐slice acquisition than do conventional multislice acquisitions. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Myocardial perfusion acquisition without magnetization preparation or gating
Authors: DiBella Edward V. R. , Chen Liyong , Schabel Matthias C. , Adluru Ganesh , McGann Chris J. 
Published: December 2011

AbstractCurrent myocardial perfusion MRI acquisitions are performed with a saturation recovery sequence, in large part to minimize sensitivity to arrhythmia. A new approach is proposed here where the images are acquired ungated at steady state without use of a saturation pulse. The data are acquired continuously and reach steady state after the first few images. A confluence of advances has made this new paradigm of an ungated steady‐state acquisition possible—very rapid undersampled readouts with new reconstruction technologies permit enough measurements that continuous acquisition becomes a feasible approach. Gating can be applied retrospectively from a logged electrocardiogram (ECG) or with self‐gating methods. In this work, simulations and measurements in a concentration phantom are used to demonstrate that similar contrast and signal can be obtained with the standard saturation recovery and the proposed spoiled gradient echo (SPGR) acquisition. Specifically, for a flip angle of 14° and a saturation recovery time of 80 ms, similar signals are acquired over a range of T1s that reflect realistic myocardial tissue concentrations. Preliminary results in one subject are presented to show the potential of this new approach. The method may allow for cine cardiac perfusion and more signal‐to‐noise ratio‐efficient acquisitions. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Null space imaging: Nonlinear magnetic encoding fields designed complementary to receiver coil sensitivities for improved acceleration in parallel imaging
Authors: Tam Leo K. , Stockmann Jason P. , Galiana Gigi , Constable R. Todd 
Published: December 2011

AbstractTo increase image acquisition efficiency, we develop alternative gradient encoding strategies designed to provide spatial encoding complementary to the spatial encoding provided by the multiple receiver coil elements in parallel image acquisitions. Intuitively, complementary encoding is achieved when the magnetic field encoding gradients are designed to encode spatial information where receiver spatial encoding is ambiguous, for example, along sensitivity isocontours. Specifically, the method generates a basis set for the null space of the coil sensitivities with the singular value decomposition and calculates encoding fields from the null space vectors. A set of nonlinear gradients is used as projection imaging readout magnetic fields, replacing the conventional linear readout field and phase encoding. Multiple encoding fields are used as projections to capture the null space information, hence the term null space imaging. The method is compared to conventional Cartesian SENSitivity Encoding as evaluated by mean squared error and robustness to noise. Strategies for developments in the area of nonlinear encoding schemes are discussed. The null space imaging approach yields a parallel imaging method that provides high acceleration factors with a limited number of receiver coil array elements through increased time efficiency in spatial encoding. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
High‐sensitivity Determination of Curcumin in Human Urine Using Gemini Zwitterionic Surfactant as a Probe by Resonance Light Scattering Technique
Authors: Chen Xi , Liang Shengwang , Zhu Li , Liu Jinbin , Zhang Guomin , Chen Zhanguang 
Published: December 2011

ABSTRACTIntroductionCurcumin is a popular plant medicine that is extracted from turmeric dry rhizomes of Curcuma longa Linn. The study of curcumin is well established and is currently becoming a centre of attention.ObjectiveTo develop a steady and simple assay for curcumin determination at the nanogram level based on the intense resonance light scattering (RLS) enhancement due to the interaction between curcumin and phosphodiesters quaternary ammonium salt (PQAS).MethodologyPQAS, a new kind of Gemini zwitterionic surfactant, was used as the probe for the determination of curcumin by the RLS technique. A series of validation experiments was also performed.ResultsA linear relationship was constructed between the ΔIRLS and the concentration of curcumin. The linear regression equation was presented as ΔIRLS = 8.37 + 44.92c (µg/mL) with the regression coefficient r = 0.9987 (n = 12) and the linear range was 0.08–60.0 µg/mL. The detection limit (3σ) was 2.6 ng/mL.ConclusionThe proposed method can be used to detect the content of curcumin in human urine samples and this new assay using PQAS as a probe was more sensitive and displayed a wider linear range than that reported previously. Copyright © 2011 John Wiley & Sons, Ltd.
Scope of network polysilanes in the synthesis of fluorescent silver and gold nanoparticles/nanoclusters‐modulations of their optical properties in the presence of Hg(II) ions
Authors: Shankar Ravi , Sahoo Usharani 
Published: December 2011

AbstractThe network polysilanes (polysilynes) [RMe2SiCH2CH2Si]n, [R=Ph (1), 2‐Furyl (2)] have been synthesized by room temperature reaction of the corresponding organotrichlorosilane with Na dispersion in tetrahydrofuran (THF) medium. The method allows the formation of high molecular weight polymers [Mw/PDI = 10,504/2.2 (1), 9176/1.5 (2)] in improved yields than those obtained from classical Wurtz coupling reaction (Na, toluene, 110 °C). These polymers act as reducing agents for Ag(I) and Au(III) ions to afford stable metal nanoparticles of 4–8 nm size domains in toluene medium. The corresponding polymer–silver nanocomposites, 1a and 2a, are fluorescent in the green light region (λmax = ∼ 530 nm) due to the formation of silver nanoclusters (AgNCs) along with the nanoparticles (AgNPs). A simple chemical approach has been developed to modulate the plasmonic and emission intensities of the nanocomposite 1a by reacting with varying concentrations (10−12 to 10−7M) of HgI2 in toluene. The method allows enhancement of the fluorescence intensity associated with AgNCs. The results are explained by invoking coupling between the energies of surface plasmon resonance and the nanocluster electronic transition. The polymer–gold nanocomposites, 1b and 2b, are non‐fluorescent and the plasmonic resonance at 530 nm associated with AuNPs is found to be insensitive to Hg(II) ions. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Plasma‐Mediated Nanosilver‐Organosilicon Composite Films Deposited on Stainless Steel: Synthesis, Surface Characterization, and Evaluation of Anti‐Adhesive and Anti‐Microbial Properties on the Model Yeast Saccharomyces cerevisiae
Authors: Saulou Claire , Despax Bernard , Raynaud Patrice , Zanna Sandrine , Seyeux Antoine , Marcus Philippe , Audinot Jean‐Nicolas , Mercier‐Bonin Muriel 
Published: December 2011

AbstractA series of plasma‐mediated thin films (≈175 nm), containing silver nanoparticles embedded in an organosilicon matrix with controllable properties (silver content, nanoparticle size, matrix composition), were deposited onto stainless steel and chemically and structurally characterized, using a large set of analytical techniques. The process originality relies on a dual strategy, associating silver sputtering, and simultaneous plasma enhanced chemical vapor deposition, in an argon‐hexamethyldisiloxane plasma, using an asymmetrical radiofrequency discharge at 13.56 MHz. X‐ray photoelectron spectroscopy, FTIR spectroscopy, and Raman spectroscopy demonstrated the inclusion of metallic silver nanoparticles within the organosilicon‐like matrix. Silver content was directly related to the plasma process conditions. TOF‐SIMS analysis revealed that the film composition was homogeneous in depth. SEM and TEM observations confirmed the nanoparticle‐based morphology of the coatings, dependent on the silver content. The film anti‐adhesive potentialities were evaluated in vitro toward the model yeast Saccharomyces cerevisiae by performing shear‐flow induced detachment experiments, under well‐controlled hydrodynamic, and physico‐chemical conditions. The maximal effect was achieved for the organosilicon matrix alone. When silver nanoparticles were incorporated, yeast detachment was lower, probably due to the strong affinity of embedded silver for biological components of the cell wall surface. The presence of methyl groups in the matrix network could also promote enhanced hydrophobic yeast/coating interactions. An anti‐microbial action of silver (conjugated effect of nanoparticles and chemisorbed Ag+ ions and complexes released through nanoparticle oxidation) at the immediate vicinity of the coating surface occurred, depending on the silver content. In the conditions under study, a maximal 1.9 log reduction in viable counts was observed, compared to control conditions with bare stainless steel. Based on NanoSIMS50 elemental mapping, various characteristic cell sub‐structures and inclusions were detected, such as cell wall and nucleus. After yeast exposure to nanosilver‐containing films, a quite homogeneous distribution of released silver all over the cell was observed, overlapping with sulfur and phosphorous signals.magnified image
Influence of annealing under reducing ambient on properties of ZnO thin films prepared by mist CVD
Authors: Kawaharamura T. , Orita H. , Shirahata T. , Yoshida A. , Fujita S. , Hirao T. 
Published: December 2011

AbstractThe resistivity of ZnO thin films grown at 300 °C with mist CVD method can be decreased about 3 orders of magnitude, from 6.2 Ωcm as deposited to 2.2×10‐2 Ωcm for the film after post annealing at 350 °C under reducing ambient of 5% H2 in N2 (forming gas: FG) with increasing mobility and without changing carrier density. It is thought that the electrical properties of the ZnO thin films with a large amount of impurities due to the low temperature growth are changed without changing surface morphology, crystal structure and impurity content after annealed in the reducing ambient. This can be explained by the decrease of disorder in the band gap in the grain and lowering of the Schottky barrier height in the grain boundaries due to the H2 interaction with oxygen. The model is supported by the quick decrease of resistivity under FG annealing. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analysis of a monolithic integrated rectenna by using an InGaAs/InAlAs triple‐barrier resonant tunneling diode for zero bias detection of submilimeter‐waves
Authors: Nakamura Masahito , Takahagi Satoshi , Saito Mitsufumi , Suhara Michihiko 
Published: December 2011

AbstractZero bias millimeter‐wave detection has been investigated by using backward diodes with InGaAs‐based or Sb‐based interband tunneling and Schottky contact InGaAs‐ based double‐barrier resonant tunneling diodes (DBRTDs). These were intended to be typical cases where the antenna and the detector are individually designed and mutually connected. On the other hand, in this paper we focus on constructing a monolithic type of rectenna (rectifying antenna) for sub‐millimeter wave detection. Our objective is to propose and analyze zero bias detection properties with an InGaAs/InAlAs triple‐barrier resonant tunneling diode (TBRTD) integrated with a bow‐tie type of broadband self‐complementary antenna. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)