bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Anticoagulant Activity System Using Nanoengineered Autofluorescent Heparin Nanotubes
Authors: Cui Wei , Cui Yue , Zhu Pengli , Zhao Jie , Su Ying , Yang Yang , Li Junbai 
Published: October 2011

AbstractHeparin (HEP) and periodate‐oxidized heparin (O‐HEP) nanotubes were prepared by combining the template method with a layer‐by‐layer (LbL) technique. The tubular structure was obtained and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and confocal laser scanning microscopy (CLSM). O‐HEP is one of the HEP derivatives that contains anticoagulant activity and preserves its ability for other effects. Chitosan (CHI) and O‐HEP have been used to fabricate nanotubes by covalent cross‐linking Schiff base reactions. It is demonstrated that the obtained nanotubes have the significant feature of autofluorescence without the addition of any fluorescent dyes and they retain their anticoagulation activity. Compared with O‐HEP/CHI nanotubes, HEP/CHI nanotubes show high anticoagulation activity and do not have autofluorescence. Furthermore, this method could be extended to other copolysaccharide derivatives for the preparation of autofluorescent nanomaterials.
A Highly Selective Colorimetric and Fluorescent Probe for Cu2+ and Hg2+ Ions Based on a Distyryl BODIPY with Two Bis(1,2,3‐triazole)amino Receptors
Authors: Shi Wen‐Jing , Liu Jian‐Yong , Ng Dennis K. P. 
Published: October 2011

AbstractA new distyryl boron dipyrromethene (BODIPY) with two bis(1,2,3‐triazole)amino substituents has been prepared by typical Knoevenagel condensation followed by click reaction. The compound selectively binds to Cu2+ and Hg2+ ions in CH3CN/H2O (1:1 v/v) to give remarkably blueshifted electronic absorption and fluorescence bands as a result of inhibition of the intramolecular charge‐transfer process upon binding to these metal ions. The color changes can be easily seen by the naked eye. The binding stoichiometry between this probe and Cu2+ ions has been determined to be 1:2 by a Job plot of the fluorescence data with a binding constant of ((6.2±0.6)×109) M−2. The corresponding value for Hg2+ ions is about sixfold smaller.
The error ellipsoid in phase space of stellar encounters and its evolution in time
Authors: Serafin R.A. , Birkenbach B. 
Published: October 2011

AbstractWe systematically investigate stellar encounters in their six‐dimensional phase space, including also the error ellipsoid and its evolution in time. It allows to give not only a mathematical model of stellar encounters but also an error model for this process. On that occasion we derive fundamental formulae for the positional error in ℝn: the probability of a position X falling into the error ellipsoid, the standard deviation in an arbitrary direction, and we briefly discuss the mean positional error in ℝn. The case of the close encounter of the star GL 710 (HIP 89825) is an illuminating example of applying the derived results. Moreover, we show that the error ellipsoid can also be successfully applied to approximate the confidence region (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The sunspot observations by Samuel Heinrich Schwabe
Authors: Arlt R. 
Published: October 2011

AbstractA long time‐series of sunspot observations is preserved from Samuel Heinrich Schwabe who made notes and drawings of sunspots from 1825–1867. Schwabe's observing records are preserved in the manuscript archives of the Royal Astronomical Society, London. The drawings have now been digitized for future measurements of sunspot positions and sizes. The present work gives an inventory and evaluation of the images obtained from the log books of Schwabe. The total number of full‐disk drawings of the sun with spots is 8486, the number of additional verbal reports on sunspots is 3699. There are also 31 reports about possible aurorae (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Angular momentum transport by thermal emission in black hole accretion disks
Authors: Johnson J.L. 
Published: October 2011

AbstractWe calculate the amount of angular momentum that thermal photons carry out of a viscous black hole accretion disk, due to the strong Doppler shift imparted to them by the high orbital velocity of the radiating disk material. While thermal emission can not drive accretion on its own, we show that along with disk heating it does nonetheless result in a loss of specific angular momentum, thereby contributing to an otherwise viscosity‐driven accretion flow. In particular, we show that the fraction of the angular momentum that is lost to thermal emission at a radius r in a standard, multi‐color disk is ∼0.4rs/r, where rs is the Schwarzschild radius of the black hole. We briefly highlight the key similarties between this effect and the closely related Poynting‐Robertson effect (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Algebraic analysis of the phase‐calibration problem in the self‐calibration procedures
Authors: Lannes A. , Prieur J.‐L. 
Published: October 2011

AbstractThis paper presents an analysis of the phase‐calibration problem encountered in astronomy when mapping incoherent sources with aperture‐synthesis devices. More precisely, this analysis concerns the phase‐calibration operation involved in the self‐calibration procedures of phase‐closure imaging. The paper revisits and completes a previous analysis presented by Lannes in the Journal of the Optical Society of America A in 2005. It also benefits from some recent developments made for solving similar problems encountered in global navigation satellite systems. In radio‐astronomy, the related optimization problems have been stated and solved hitherto at the phasor level. We present here an analysis conducted at the phase level, from which we derive a method for diagnosing and solving the difficulties of the phasor approach. In the most general case, the techniques tobe implemented appeal to the algebraic graph theory and the algebraic number theory. The minima of the objective functionals to be minimized are identified by raising phase‐closure integer ambiguities. We also show that in some configurations, to benefit from all the available information, closure phases of order greater than three are to be introduced. In summary, this study leads to a better understanding of the difficulties related to the very principle of phase‐closure imaging. To circumvent these difficulties, we propose a strategy both simple and robust (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bottom‐up modeling and simulation of tacrolimus clearance: prospective investigation of blood cell distribution, sex and CYP3A5 expression as covariates and assessment of study power
Authors: Ohtani Hisakazu , Barter Zoe , Minematsu Tsuyoshi , Makuuchi Masatoshi , Sawada Yasufumi , Rostami‐Hodjegan Amin 
Published: October 2011

ABSTRACTThe objectives were to investigate the ability of population‐based in vitro–in vivo extrapolation (IVIVE) to reproduce the influence of haematocrit on the clearance of tacrolimus, observed previously, and to assess the power of clinical studies to detect the effects of covariates on the clearance of tacrolimus.A population‐based pharmacokinetic simulator (Simcyp) was used to simulate tacrolimus clearance from in vitro metabolism data and demographic characteristics of Japanese liver transplant patients (JLTs). The relationship between haematocrit and dose‐to‐concentration (D/C) ratio was validated using seven JLTs, whose highly variable haematocrit and D/C ratio were previously analysed. This validation was used as a surrogate for establishing ‘interindividual’ variability and to assess the power of clinical studies to discern the effect of haematocrit, sex and CYP3A5 genotype on tacrolimus clearance in a virtual JLT population.The relationship between haematocrit and D/C ratio was reproducible by Simcyp and corresponded well to those observed in seven JLTs. The number of JLTs required to detect the influence of CYP3A5 genotype and sex were estimated to be about 50 and > 600, respectively, which was consistent with the results of previous population pharmacokinetic studies for tacrolimus.In conclusion, population‐based IVIVE is considered to be a useful approach to assess the influence of covariates a priori before conducting clinical studies. This is also helpful with study design and assessment of the statistical power of clinical studies involving population‐based pharmacokinetics to detect the effects of covariates. Copyright © 2011 John Wiley & Sons, Ltd.
The extended ocular hypotensive effect of positive liposomal cholesterol bound timolol maleate in glaucomatous rabbits
Authors: Shafaa Medhat W. , Sabra Neveen M. , Fouad Rehab A. 
Published: October 2011

ABSTRACTIncreased intraocular pressure (IOP) is a significant risk factor for the development of glaucoma. Timolol maleate is a beta‐adrenergic receptor blocking agent and it is used for the treatment of glaucoma in order to reduce the elevated IOP that is characteristic of this eye disease. Systemic toxicity from topical timolol occurs more frequently than local toxicity and can affect the pulmonary, cardiac and central nervous systems. The objective of the present study, therefore, was to formulate multilamellar vesicles (MLVs) liposomal preparations of timolol maleate using their advantage of being less toxic compared with non‐liposome‐based drugs to be applied topically and to evaluate the in vivo performance of the prepared liposomes to extend the time of reduced IOP of glaucomatous rabbit's eye measured using a standard Shiotz tonometer. The encapsulation efficiency of MLVs was measured using a spectrophotometric technique. Differential scanning calorimetry (DSC) was used to monitor the effects of timolol maleate in the absence and presence of cholesterol on liposome thermal behaviour. Positively charged MLVs of timolol in the presence of a lower amount of cholesterol (DPPC(7):Chol(2):Timolol(2):SA(1) molar ratio) were found to be superior compared with other formulations in extending the ocular hypotensive effect approximately for 1 week (160 h) which encourages its physiological effectiveness. The increase of the cholesterol molar ratio in the prepared liposomal formulations serves to decrease the permeability of the lipid bilayer that is manifested by a low rate of drug release, an increased percentage of entrapment efficiency and a consequently lower bioavailability. Copyright © 2011 John Wiley & Sons, Ltd.
Effort and Fairness in Bargaining Games
Authors: Franco‐Watkins Ana M. , Edwards Bryan D. , Acuff Roy E. 
Published: October 2011

ABSTRACTMost real‐world negotiations involving monetary transactions require exertion of effort to procure services or commodities. Economic games that require individuals to split a pot of money (windfall) measure fairness boundaries in negotiations without accounting for effort. To examine how effort affects perceptions of fairness and allocation of resources during bargaining situations, we compared windfall with business situations in three experiments designed to examine effort from several unique perspectives: (a) implied effort manipulated by game description (all experiments); (b) perceptions of effort (Experiments 2 and 3); and (c) manipulation of indirect effort (Experiment 3). A consistent pattern emerged demonstrating that earned (through effort) and windfall monetary transactions differentially influenced perceived fairness. When effort was expended, participants placed a larger monetary value on that effort and compensated themselves and others accordingly. When no effort was involved, participants relied on egalitarian fairness norms. Copyright © 2011 John Wiley & Sons, Ltd.
Multiple imputation methods for inference on cumulative incidence with missing cause of failure
Authors: Lee Minjung , Cronin Kathleen A. , Gail Mitchell H. , Dignam James J. , Feuer Eric J. 
Published: October 2011

AbstractAnalysis of cumulative incidence (sometimes called absolute risk or crude risk) can be difficult if the cause of failure is missing for some subjects. Assuming missingness is random conditional on the observed data, we develop asymptotic theory for multiple imputation methods to estimate cumulative incidence. Covariates affect cause‐specific hazards in our model, and we assume that separate proportional hazards models hold for each cause‐specific hazard. Simulation studies show that procedures based on asymptotic theory have near nominal operating characteristics in cohorts of 200 and 400 subjects, both for cumulative incidence and for prediction error. The methods are illustrated with data on survival after breast cancer, obtained from the National Surgical Adjuvant Breast and Bowel Project (NSABP).
Development of Dispersive Liquid–Liquid Microextraction Based on Solidification of Floating Organic Drop for the Determination of Trace Lead in Water
Authors: Zhang Jing‐Wen , Wang Yu‐Kun , Du Hai‐Ying , Du Xin , Ma Jing‐Jun , Li Jing‐Ci 
Published: October 2011

AbstractA new method for determining lead (Pb) content was developed by dispersive liquid–liquid microextraction based on the solidification of floating organic droplets followed by flame atomic absorption spectrometry. Under optimum conditions, the calibration graph was linear within the Pb content range of 8.43–400 µg L−1 with a detection limit of 2.53 µg L−1. The relative standard deviation for 10 replicate measurements of 20 and 400 µg L−1 of Pb were 3.41 and 2.78%, respectively. The proposed method was assessed through the analysis of certified reference water and recovery experiments.
Signal transduction in a compliant short loop of Henle
Authors: Layton Anita T. , Pham Philip , Ryu Hwayeon 
Published: October 2011

SUMMARYTo study the transformation of fluctuations in filtration rate into tubular fluid chloride concentration oscillations alongside the macula densa, we have developed a mathematical model for tubuloglomerular feedback (TGF) signal transduction along the pars recta, the descending limb, and the thick ascending limb (TAL) of a short‐looped nephron. The model tubules are assumed to have compliant walls and, thus, a tubular radius that depends on the transmural pressure difference. Previously, it has been predicted that TGF transduction by the TAL is a generator of nonlinearities: if a sinusoidal oscillation is added to a constant TAL flow rate, then the time required for a fluid element to traverse the TAL is oscillatory in time but nonsinusoidal. The results from the new model simulations presented here predict that TGF transduction by the loop of Henle is also, in the same sense, a generator of nonlinearities. Thus, this model predicts that oscillations in tubular fluid alongside the macula densa will be nonsinusoidal and will exhibit harmonics of sinusoidal perturbations of pars recta flow. Model results also indicate that the loop acts as a low‐pass filter in the transduction of the TGF signal. Copyright © 2011 John Wiley & Sons, Ltd.
Rotational Energy Transfer of SH(X2Π, v′′=0, J′′=0.5–10.5) by Collision with Ar: Λ‐Doublet Resolved Transition Propensity
Authors: Tsai Po‐Yu , Lin King‐Chuen 
Published: October 2011

AbstractThe behavior of Λ‐doublet resolved rotational energy transfer (RET) by Ar collisions within the SH(X2Π, v′′=0) state is characterized. The matrix elements of terms in the interaction potential responsible for interference effects are calculated to explain the propensity rules for collision‐induced transitions within and between spin–orbit manifolds. In this manner, the physical mechanisms responsible for the F1–F1, F2–F2, and F1–F2 transitions may be reasonably identified. As collision energy increases, the propensity for collisional population of the final e or f level is replaced by the e/f‐conserving propensity. Such a change in propensity rule can be predicted in terms of energy sudden approximation at high J limit for the pure Hund’s case scheme.
On ‘a simple three‐party password‐based key exchange protocol’
Authors: Lin Ching‐Ying , Hwang Tzonelih 
Published: October 2011

AbstractIn 2009, Huang (Int. J. Commun. Syst., 22, 857–862) proposed a simple and efficient three‐party password‐based key exchange protocol without server's public key. This work shows that the protocol could be vulnerable to an undetectable online password guessing attack. Furthermore, an improved protocol is proposed to avoid the attack. Copyright © 2011 John Wiley & Sons, Ltd.
Performance evaluation of priority based adaptive multiguard channel call admission control for multiclass services in mobile networks
Authors: Yang Shun‐Fang , Wu Jung‐Shyr , Hwang Bor‐Jiunn 
Published: October 2011

SUMMARYThe CAC (call admission control), which can guarantee call services to meet their QoS (Quality of Service) requirements, plays a significant role in providing QoS in wireless mobile networks. In this paper, an adaptive multiguard channel scheme‐based CAC strategy is proposed to prioritize traffic types and handoff calls. The major aim of the study is to develop the analytical model of the priority traffic and handoff calls based adaptive multiguard channel scheme and examining the performance through setting the value of the adaptive ratio parameters. Our proposed scheme tries to mediate the advantages and drawbacks of the static and dynamic CAC schemes. The proposed scheme is quite different from previous studies because multithreshold values have been considered for multiclass traffic by adaption parameters, and a closed form analytical model is developed The numerical results show that this scheme can be used to keep the targeted QoS requirement by suitably setting the adaptive ratio parameters. Copyright © 2011 John Wiley & Sons, Ltd.
Process‐based proxy of oxygen stress surpasses indirect ones in predicting vegetation characteristics
Authors: Bartholomeus Ruud P. , Witte Jan‐Philip M. , van Bodegom Peter M. , van Dam Jos C. , de Becker Piet , Aerts Rien 
Published: October 2011

ABSTRACTRobust relationships among soil, water, atmosphere and plants are needed to reliably forecast the plant species composition. In this paper, we show the need for, and the application of, a process‐based relationship between soil moisture conditions and vegetation characteristics. We considered 366 groundwater‐dependent sites, where oxygen stress, caused by a surplus of soil moisture, codetermines plant performance. We compared two existing indirect proxies for the soil oxygen status – namely mean spring groundwater level (MSL) and sum exceedence value (SEV) – with our newly developed process‐based proxy, viz. root respiration stress (RS). The two indirect proxies and the process‐based proxy for oxygen stress performed equally well in describing vegetation characteristics for the Netherlands under the current climate. However, relationships based on MSL and SEV appeared to produce systematic prediction errors when applied outside their calibration range, in contrast to the relationship based on RS. Hence, the two indirect proxies cannot be used in projections, such as in predicting effects of climate change on vegetation composition, all the more because they – unlike RS – do not account for essential parameters that determine oxygen stress (e.g. temperature and extreme rainfall events in the growing season). We advocate using RS for estimating vegetation impacts in climate projections to increase the reliability and effectiveness of adaptive strategies. Copyright © 2011 John Wiley & Sons, Ltd.
Enhancement of anti‐tumor immunity through local modulation of CTLA‐4 and GITR by dendritic cells
Authors: Pruitt Scott K. , Boczkowski David , de Rosa Nicole , Haley N. Rebecca , Morse Michael A. , Tyler Douglas S. , Dannull Jens , Nair Smita 
Published: October 2011

AbstractCancer vaccines have now demonstrated clinical efficacy, but immune modulatory mechanisms that prevent autoimmunity limit their effectiveness. Systemic administration of mAbs targeting the immune modulatory receptors CTLA‐4 and glucocorticoid‐induced TNFR‐related protein (GITR) on Treg and effector T cells augments anti‐tumor immunity both experimentally and clinically, but can induce life‐threatening autoimmunity. We hypothesized that local delivery of anti‐CTLA‐4 and anti‐GITR mAbs to the sites where T cells and tumor antigen‐loaded DC vaccines interact would enhance the induction of anti‐tumor immunity while avoiding autoimmunity. To achieve this goal, DCs transfected with mRNA encoding the H and L chains of anti‐mouse CTLA‐4 and GITR mAbs were co‐administered with tumor antigen mRNA‐transfected DCs. We observed enhanced induction of anti‐tumor immunity and significantly improved survival in melanoma‐bearing mice, without signs of autoimmunity. Using in vitro assays with human DCs, we demonstrated that DCs transfected with mRNA encoding a humanized anti‐CTLA‐4 mAb and mRNA encoding a soluble human GITR‐L fusion protein enhance the induction of anti‐tumor CTLs in response to DCs transfected with mRNAs encoding either melanoma or breast cancer antigens. Based on these results, this approach of using local delivery of immune modulators to enhance vaccine‐induced immunity is currently being evaluated in a phase I clinical cancer immunotherapy trial.
BAFF‐R expression correlates with positive selection of immature B cells
Authors: Tussiwand Roxane , Rauch Melanie , Flück Lukas A. , Rolink Antonius G. 
Published: October 2011

AbstractThe interaction between BAFF and BAFF‐R is crucial for the development of mature B cells. Here, we report that the expression of BAFF‐R is first detectable on a fraction of mouse CD19+ CD93+ IgM+ CD23– and human CD19+ CD10+ IgM+ BM B cells. This BAFF‐R+ BM B‐cell population shows higher levels of surface IgM expression and decreased RAG‐2 transcripts than BAFF‐R– immature B cells. When cultured, mouse BAFF‐R–, but not BAFF‐R+ immature B cells spontaneously undergo B‐cell receptor editing. However, BAFF‐R+ immature B cells cultured in the presence of an anti‐κ light chain antibody are induced to undergo receptor editing. This receptor editing correlates with down‐modulation of surface BAFF‐R expression and the up‐regulation of RAG‐2 at the RNA level. B‐cell receptor (BCR) cross‐linking on splenic T1 B cells results in down‐modulation of the BAFF‐R, and receptor editing and RAG‐2 up‐regulation in a minor fraction of B cells. BCR cross‐linking on splenic T2/3 B cells results in partly down and partly up‐modulation of BAFF‐R expression and no evidence for receptor editing. Overall, our data indicate that BAFF‐R expression is tightly regulated during B‐cell development in mouse and human and its expression is correlated with positive selection.