bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intuitive learning of communication protocols by using a sniffer
Authors: Fernandez Marcos D. , Martinez Jesus A. 
Published: February 2009

AbstractNetwork sniffers have become critical tools in today's networking management and troubleshooting processes. They enable network managers to evaluate and examine the data running through their network, as well as it can help to identify network attacks and to detect security threats. Besides their usage in the technical environment, network sniffers can be used for educational and research purposes. They can be used for a better understanding of packets' architecture and traffic patterns generated by common network applications. Network Sniffers can also be used to evaluate protocol performance and assist in protocol development. Then, an essential part of a Networking course is the examination of and experimentation with network traffic data and protocols. Most standalone network traffic sniffers are rather expensive and those freely available on general purpose platforms (Linux or Windows) are quite cryptic. Therefore, we have developed a sniffing environment that permits to analyse network data and to send data packets. This sniffer is intended for beginner students in networking and it gives a clear guidance for its use. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 18: 721–726, 2010; View this article online at wileyonlinelibrary.com; DOI 10.1002/cae.20277
Development of a visual courseware for surface mining education
Authors: Akkoyun Ozgur 
Published: February 2009

AbstractIn this paper, new visual courseware for surface mining education is described. It has been developed to help and support the lecturer when teaching and as a self‐study tool for students in learning surface mining methods. The software enables the constructors, students and engineers to analyze whole mining and economical aspects of surface mining methods and is fully implemented using graphical user interface technology. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 56–65, 2011
Structure–Affinity Relationship Study of Bleomycins and Shble Protein by Use of a Chemical Array
Authors: Miyazaki Isao , Okumura Hideo , Simizu Siro , Takahashi Yoshikazu , Kanoh Naoki , Muraoka Yasuhiko , Nonomura Yoshiaki , Osada Hiroyuki 
Published: February 2009

AbstractNatural product libraries for SAR studies: We used a chemical array platform to study the SARs of bleomycin (BLM) derivatives and Shble protein. The on‐chip SARs suggested that several domains are important for recognition of BLMs by Shble protein. In particular, the C‐terminal tail and the propionamide moiety in pyrimidoblamic acid (PBA) were shown to be important for the binding.magnified imageThe photocrosslinked chemical array format is useful not merely for screening protein ligands, but also for gaining insight into structure–affinity relationships (SARs). By probing an array of 2000 natural products, containing 50 bleomycin (BLM) derivatives, with cell lysates that overexpress RFP‐fused Shble protein, we successfully observed interactions between Shble protein and BLMs on the array. Among the BLM derivatives, those that had long C‐terminal tails were found to bind strongly. The binding signal intensities observed on the chemical array correlated well with the association constants, which were determined by isothermal titration carolimetry (ITC) experiments (r2=0.663), showing that the on‐chip results were not an artifact of ligand immobilization. In addition to the C‐terminal tails, the propionamide moieties in pyrimidoblamic acid (PBA) also appeared to be important for binding. The contributions of the propionamide moieties of PBA to binding were further supported by the X‐ray structure of the complex of Shble protein and BLM A6. These results provide insight into the structural requirements for recognition of BLMs by Shble protein.
The Double Solubility Rule Holds for Racemizing Enantiomers
Authors: Izumi Toshiko , Blackmond Donna G. 
Published: February 2009

AbstractChiral amnesia: Experimental results demonstrate that the double solubility rule indeed holds true for the solution‐phase enantiomers of a conglomerate‐forming solid under fast‐racemizing conditions. There is neither experimental evidence for chiral recognition via solution‐phase clusters nor a need to invoke them to produce a lucid explanation of the compelling model for the evolution of solid‐phase homochirality first communicated by Viedma.magnified image
Solvent‐Assisted Organized Structures Based on Amphiphilic Anion‐Responsive π‐Conjugated Systems
Authors: Maeda Hiromitsu , Ito Yoshihiro , Haketa Yohei , Eifuku Nazuki , Lee Eunji , Lee Myongsoo , Hashishin Takeshi , Kaneko Kenji 
Published: February 2009

AbstractJust subtract water: Amphiphilic π‐conjugated acyclic oligopyrroles form solvent‐assisted H‐aggregates that give rise to vesicular structures in aqueous solution (see figure). The H‐aggregates are sensitive to the conditions and are transformed into J‐aggregates by the removal of water.magnified imageThe synthesis of amphiphilic π‐conjugated acyclic oligopyrroles and the formation of solvent‐assisted aggregates are reported. We have prepared various types of BF2 complexes of 1,3‐dipyrrolylpropane‐1,3‐diones bearing aryl rings substituted with hydrophilic polyethyleneglycol (PEG) chains, both as acyclic anion receptors and as building subunits for organized architectures based on π–π stacking. The formation of supramolecular H‐type assemblies of these “amphiphilic” derivatives in aqueous solution was suggested by UV/Vis and fluorescence spectroscopy and further supported by 1H NMR and dynamic light scattering (DLS) analyses. Cryogenic transmission electron microscopy (cryo‐TEM) analyses of the aqueous solutions suggest that the fabrication of nanoscale network structures and vesicles depends on the peripheral substituents. The H‐aggregates in aqueous solution are sensitive to the conditions required for transformation into monomers through replacement with miscible solvents such as alcohols and into J‐type aggregates by water evaporation and freeze‐drying procedures. However, they are fairly stable and sustainable to anion binding, whereas on CH2Cl2 extraction they are transformed into other assembled modes but remain in the aqueous solution. The metastable states of affairs for distributions between two immiscible solvents are controlled by the orders of solution preparation; this also suggests that the formation of stable assemblies is assisted by water molecules. Furthermore, assemblies in which the stacking modes depend on the aliphatic side chains are also observed in a nonpolar hydrocarbon solvent.
A Mechanically Interlocked [3]Rotaxane as a Light‐Harvesting Antenna: Synthesis, Characterization, and Intramolecular Energy Transfer
Authors: Wang Jie‐Yu , Han Ji‐Min , Yan Jing , Ma Yuguo , Pei Jian 
Published: February 2009

AbstractMimicking photosynthesis: The concept of light‐harvesting by using a mechanically interlocked [3]rotaxane is developed through synthesis and characterization. Our results provide a new candidate for light‐harvesting systems and also open up the possibility of creating intelligent or controllable energy‐collecting machines (see figure).magnified imageA mechanically interlocked light‐harvesting system [3]rotaxane A has been synthesized in high yield through Cu(I)‐catalyzed azide–alkyne cycloaddition; the hexyl‐substituted truxene units are introduced into the wheels as donors and an oligo(para‐phenylenevinylene) (OPV) unit into the axis as the acceptor. The structure and the purity of [3]rotaxane A were confirmed by 1H and 13C NMR spectroscopy and ESI HRMS. The azide–alkyne cycloaddition is demonstrated to be an efficient stoppering method in the synthesis of the rotaxane containing dibenzo[24]crown‐8 and dibenzyl ammonium units. Detailed steady‐state UV/Vis absorption, photoluminescent, and time‐resolved fluorescence spectroscopy were performed to investigate the photophysical properties of [3]rotaxane A and its reference compounds in solution and as thin films. Even in dilute solution, efficient energy transfer from the truxene‐functionalized wheels to the OPV‐based axis, through the dibenzo[24]crown‐8 and dibenzyl ammonium interaction, is observed in [3]rotaxane A. The unique topology of [3]rotaxane A not only efficiently promotes the intramolecular energy‐transfer process, but also prevents intermolecular aggregation in the solid state. The new antenna system opens up the possibility of controllable light‐harvesting molecular machines or other optoelectronic devices on the nanometer scale.
Intramolecular Metal–Fluorocarbon Coordination, CF Bond Activation and Lanthanoid–Fluoride Clusters with Tethered Polyfluorophenylamide Ligands
Authors: Deacon Glen B. , Forsyth Craig M. , Junk Peter C. , Wang Jun 
Published: February 2009

AbstractActivating CF bonds: Strong metal–fluorocarbon coordination in complexes of electropositive metals (e.g., Na, K, Yb) with chelating polyfluorophenyl‐substituted amide ligands is a precursor to CF bond activation and fluoride abstraction when M=YbII, giving heteroleptic YbIII fluoride clusters (see scheme).magnified imageMetalation of either N,N‐diethyl‐ or N,N‐dimethyl‐N′‐2,3,5,6‐tetrafluorophenylethane‐1,2‐diamines (HL 1 a, 1 b respectively) with [M{N(SiMe3)2}] (M=Na, K) or [Yb{N(SiMe3)2}2(thf)2] yielded the metal–amido compounds [Na(L)] (2 a), [K(L)] (3 a) and [Yb(L)2(thf)2] (4 a, 4 b). The Yb complexes were also synthesised by redox transmetalation/ligand exchange from Yb, Hg(C6F5)2 and HL in THF or 4 a from a reaction of 3 a with YbI2 in THF. In the presence of N,N,N′,N′‐ tetramethyl‐1,2‐ethanediamine (TMEDA) the complexes 2 a and 3 a yielded [Na(L)2Na(tmeda)] (5 a) and [K2(L)2(tmeda)2] (6 a), respectively, as crystalline compounds, whilst crystallisation of 4 a from DME gave [Yb(L)2(dme)] (7 a). Their structures have chelating metal–amide and NR2 donors and additional intramolecular M‐F‐C connectivity with relatively short bond lengths (NaF 2.65–3.00 Å; KF 2.70–3.00 Å; YbF 2.56 Å). The Yb complexes undergo CF activation in solution forming [Yb4(L)6F6] (8 a, 8 b). The connectivity of [Yb4(L)6F6], as shown by the X‐ray structures, comprised a circular Yb4(μ‐F)4 periphery with two opposing Yb centres having either one L ligand and a Yb2(μ‐F)2 bridge or two L ligands. Each polyfluorophenylamide exhibits additional intramolecular Yb‐F‐C coordination from one of the ortho‐F atoms resulting in seven or eight coordinate Yb centres. An attempt to synthesise 4 a by redox transmetalation/ligand exchange using Hg(CCPh)2 as the mercury reagent gave [Yb4(O)2(L)4(CCPh)4(thf)2]⋅THF (9 a⋅THF), most likely as a result of oxidation of the initially formed product.
Stereoselective SE2′ Protonation of α‐Hydroxyallylsilanes Mediated by a Brook Rearrangement
Authors: Sasaki Michiko , Shirakawa Yuri , Kawahata Masatoshi , Yamaguchi Kentaro , Takeda Kei 
Published: February 2009

AbstractBrooked up! Treatment of (R,Z)‐3‐(tert‐butyldimethylsilyl)‐1‐cyano‐3‐hydroxyprop‐1‐enyl carbamate with a catalytic amount of a base afforded (S,E)‐3‐(tert‐butyldimethylsilyloxy)‐1‐cyanoallyl diisopropylcarbamate, showing that SE2′‐type reaction of allylsilicates proceeds in an anti fashion. The overall process is equivalent to trapping of an enantioenriched C‐chiral carbanion at the α‐position of nitrile group in up to 77 % ee (see scheme).magnified image
Penalized contrast estimator for adaptive density deconvolution
Authors: Comte Fabienne , Rozenholc Yves , Taupin Marie‐Luce 
Published: February 2009

AbstractThe authors consider the problem of estimating the density g of independent and identically distributed variables XI, from a sample Z1,… Zn such that ZI = XI + σϵ for i = 1,…, n, and E is noise independent of X, with σϵ having a known distribution. They present a model selection procedure allowing one to construct an adaptive estimator of g and to find nonasymptotic risk bounds. The estimator achieves the minimax rate of convergence, in most cases where lower bounds are available. A simulation study gives an illustration of the good practical performance of the method.
Strictly monotone and smooth nonparametric regression for two or more variables
Authors: Dette Holger , Scheder Regine 
Published: February 2009

AbstractThe authors propose a new monotone nonparametric estimate for a regression function of two or more variables. Their method consists in applying successively one‐dimensional isotonization procedures on an initial, unconstrained nonparametric regression estimate. In the case of a strictly monotone regression function, they show that the new estimate and the initial one are first‐order asymptotic equivalent; they also establish asymptotic normality of an appropriate standardization of the new estimate. In addition, they show that if the regression function is not monotone in one of its arguments, the new estimate and the initial one have approximately the same Lp‐norm. They illustrate their approach by means of a simulation study, and two data examples are analyzed.
A kernel smoothing method of adjusting for unit non‐response in sample surveys
Authors: Silva DamiãoN. Da , Opsomer Jean D. 
Published: February 2009

AbstractNon‐response is a common problem in survey sampling and this phenomenon can only be ignored at the risk of invalidating inferences from a survey. In order to adjust for unit non‐response, the authors propose a weighting method in which kernel regression is used to estimate the response probabilities. They show that the adjusted estimator is consistent and they derive its asymptotic distribution. They also suggest a means of estimating its variance through a replication‐based technique. Furthermore, a Monte Carlo study allows them to illustrate the properties of the non‐response adjustment and its variance estimator.
Goodness‐of‐fit tests for parametric models in censored regression
Authors: Pardo‐Fernández Juan Carlos , Van Keilegom Ingrid , González‐Manteiga Wenceslao 
Published: February 2009

AbstractThe authors propose a goodness‐of‐fit test for parametric regression models when the response variable is right‐censored. Their test compares an estimation of the error distribution based on parametric residuals to another estimation relying on nonparametric residuals. They call on a bootstrap mechanism in order to approximate the critical values of tests based on Kolmogorov‐Smirnov and Cramér‐von Mises type statistics. They also present the results of Monte Carlo simulations and use data from a study about quasars to illustrate their work.
Generalized likelihood ratio tests for the structure of semiparametric additive models
Authors: Jiang Jiancheng , Zhou Haibo , Jiang Xuejun , Peng Jianan 
Published: February 2009

AbstractSemiparametric additive models (SAMs) are very useful in multivariate nonparametric regression. In this paper, the authors study nonparametric testing problems for the nonparametric components of SAMs. Using the backfitting algorithm and the local polynomial smoothing technique, they extend to SAMs the generalized likelihood ratio tests of Fan &Jiang (2005). The authors show that the proposed tests possess the Wilks‐type property and that they can detect alternatives nearing the null hypothesis with a rate arbitrarily close to root‐n while error distributions are unspecified. They report simulations which demonstrate the Wilks phenomenon and the powers of their tests. They illustrate the performance of their approach by simulation and using the Boston housing data set.
Longitudinal data analysis for generalized linear models with follow‐up dependent on outcome‐related variables
Authors: BU̇rŽKOVÁ Petra , Lumley Thomas 
Published: February 2009

AbstractIn longitudinal studies, observation times are often irregular and subject‐specific. Frequently they are related to the outcome measure or other variables that are associated with the outcome measure but undesirable to condition upon in the model for outcome. Regression analyses that are unadjusted for outcome‐dependent follow‐up then yield biased estimates. The authors propose a class of inverse‐intensity rate‐ratio weighted estimators in generalized linear models that adjust for outcome‐dependent follow‐up. The estimators, based on estimating equations, are very simple and easily computed; they can be used under mixtures of continuous and discrete observation times. The predictors of observation times can be past observed outcomes, cumulative values of outcome‐model covariates and other factors associated with the outcome. The authors validate their approach through simulations and they illustrate it using data from a supported housing program from the US federal government.
Bayesian spatio‐temporal models based on discrete convolutions
Authors: Sans Ó Bruno , Schmidt Alexandra M. , Nobre Aline A. 
Published: February 2009

AbstractAbstract: The authors consider a class of models for spatio‐temporal processes based on convolving independent processes with a discrete kernel that is represented by a lower triangular matrix. They study two families of models. In the first one, spatial Gaussian processes with isotropic correlations are convoluted with a kernel that provides temporal dependencies. In the second family, AR(p) processes are convoluted with a kernel providing spatial interactions. The covariance structures associated with these two families are quite rich. Their covariance functions that are stationary and separable in space and time as well as time dependent nonseparable and nonisotropic ones.
Predictors of Stroke Risk in Native Chinese with Nonrheumatic Atrial Fibrillation: Retrospective Investigation of Hospitalized Patients
Authors: Sun Yihong , Hu Dayi , Li Kuibao , Zhou Ziqiang 
Published: February 2009

AbstractBackgroundData on stroke risk factor profiles and atrial fibrillation (AF) for the Chinese population are sparse. This study identified risk factors for stroke among native Chinese with nonrheumatic AF.MethodsIn this retrospective investigation, patients diagnosed with nonrheumatic AF were identified from 18 hospitals in representative areas of the country, from January 2000 to April 2002, based on the medical records. All parameters relevant to AF were compared between AF patients with stroke and those without. The independent risk factors for stroke were assessed with a logistic regression analysis.ResultsPatients numbering 3,425 with AF were included, among whom 827 subjects were discharged on account of stroke. The prevalence of stroke in nonrheumatic AF patients was 24.15%. AF patients with stroke were significantly older than controls (73.31 ± 9.18 versus 68.22 ± 12.29 y, p < 0.001) and more likely to have a history of hypertension (71.0 versus 51.6%, p < 0.001) and diabetes (17.9 versus 11.1%, p = 0.001).Both, systolic and diastolic blood pressure, are significantly higher in patients with stroke. Of all the parameters of echocardiography, there was strong evidence that left atrial (LA) thrombi significantly increased risk of stroke. Patients with persistent AF were more likely to have stroke than paroxysmal AF patients, while lone AF is less in patients with stroke than in those without. The rate of anticoagulation treatment is only 9.27%, but there were no significant differences between the 2 groups. In multivariate analysis, age ≥ 75 y (odds ratio [OR] 1.76; 95% confidence interval [CI] 1.08‐2.98), history of hypertension (OR 1.52; 95% CI 1.28‐1.80), diabetes (OR 1.39; 95% CI 1.11‐1.76), high systolic blood pressure (OR 1.71; 95% CI 1.21‐2.28), LA thrombi (OR 2.77; 95% CI 1.25‐6.13) were independent predictors for stroke.ConclusionsThe prevalence of stroke in hospitalized nonrheumatic AF patients was high. The population‐specific risk factors for stroke were age ≥ 75 y, diabetes, history of hypertension, high systolic blood pressure and LA thrombi by transesophageal echocardiography (TEE). These merit further evaluation. Copyright © 2009 Wiley Periodicals, Inc.
Prognostic impact of mitotic index of proliferating cell populations in cervical cancer patients treated with carbon ion beam
Authors: Suzuki Yoshiyuki , Oka Kuniyuki , Ohno Tatsuya , Kato Shingo , Tsujii Hirohiko , Nakano Takashi 
Published: February 2009

AbstractBACKGROUND:The authors previously reported that the mitotic index of a proliferating cell population (pMI) was a potent prognostic factor in cervical cancer patients treated with photon beam therapy. In this study, they investigated whether the pMI accurately predicted prognosis in cervical cancer patients treated with carbon ion beam.METHODS:Tissue sections were obtained from 27 consecutively treated patients with stage IIIB bulky (19 patients) and stage IVA (8 patients) squamous cell carcinomas of the cervix treated with carbon ion beam at the National Institute of Radiological Sciences, Japan, as a phase I/II study with dose escalation methodology (52.8‐72 grays equivalent radiation dose/24 fractions). The mitotic index (MI) and Ki‐67 labeling index (Ki‐67‐LI) were determined by hematoxylin and eosin staining and immunohistochemical staining, respectively. The pMI was calculated using the following formula: pMI = MI/Ki‐67‐LI.RESULTS:The pMI ranged from 0.6 to 8.9 (mean, 3.9 ± 2.6; median, 3.2). Twelve of the 27 specimens had a pMI >3.5. The local control rate in tumors with a pMI >3.5 was 17%, significantly lower than the 73% in the tumors with a pMI <3.5 (P = .005). Multivariate analysis indicated that the pMI had the strongest impact on local control (standard regression coefficient = 0.48, P = .002) among the variables, including clinical stage, irradiated dose, age, and tumor volume.CONCLUSIONS:These results suggest that a high pMI is an indication of a poorer prognosis, and is a powerful prognostic factor in patients with squamous cell carcinomas of the cervix treated with carbon ion beam therapy. Cancer 2009. © 2009 American Cancer Society.
Combustion of CH4/H2/Air Mixtures in Catalytic Microreactors
Authors: Specchia Stefania , Vella Luigi D. , Burelli Sara , Saracco Guido , Specchia Vito 
Published: February 2009

AbstractThe combustion of CH4 and H2 in a confined space represents an innovative way to produce heat and power. Burning tests on CH4/H2/air mixtures using Pd/NiCrO4‐catalyst‐lined SiC monoliths (see picture) show an important reduction of both the ignition temperature and the 100 % conversion temperature in these systems.magnified imageThe combustion of CH4/H2/HC mixtures in a very small space represents an alternative, innovative way to produce thermal/electrical energy. Pd/NiCrO4 catalysts are lined on SiC monoliths via in situ solution combustion synthesis (SCS), and the monoliths are then tested by feeding CH4, H2, and lean CH4/H2 mixtures into a lab‐scale test rig at an output thermal power of 7.6 MWth m−3. In all cases, the combustion temperature shifts to values lower than those observed in non‐catalytic combustion. When the power density is kept constant (by adding H2 to the gas mixture), the value of CH4–T50 (the half‐conversion temperature of CH4) decreases relative to that of pure CH4, and the slope of the conversion curve becomes steeper. The higher the H2 concentration is, the higher the reactivity of the mixture towards CH4 oxidation—probably due to a higher production of H2 reactive radicals (OH).