bluuebunny/crossref_metadata_2025_split huggingface dataset:
CX⋅⋅⋅O Halogen Bonding: Interactions of Trifluoromethyl Halides with Dimethyl Ether
Authors: Hauchecorne Dieter , Szostak Roman , Herrebout Wouter A. , van der Veken Benjamin J. 
Published: July 2009

AbstractThe formation of weakly bound molecular complexes between dimethyl ether (DME) and the trifluoromethyl halides CF3Cl, CF3Br and CF3I dissolved in liquid argon and in liquid krypton is investigated, using Raman and FTIR spectroscopy. For all halides evidence is found for the formation of CX⋅⋅⋅O halogen‐bonded 1:1 complexes. At higher concentrations of CF3Br, a weak absorption due to a 1:2 complex is also observed. Using spectra recorded at temperatures between 87 and 125 K, the complexation enthalpies for the complexes are determined to be −6.8(3) kJ mol−1 (DME⋅CF3Cl), −10.2(1) kJ mol−1 (DME⋅CF3Br), −15.5(1) kJ mol−1 (DME⋅CF3I), and −17.8(5) kJ mol−1 [DME(⋅CF3Br)2]. Structural and spectral information on the complexes is obtained from ab initio calculations at the MP2/ 6‐311++G(d,p) and MP2/6‐311++G(d,p)+LanL2DZ* levels. By applying Monte Carlo free energy perturbation calculations to account for the solvent influences, and statistical thermodynamics to estimate the zero‐point vibrational and thermal influences, the ab initio complexation energies are converted into complexation enthalpies for the solutions in liquid argon. The resulting values are compared with the experimental data deduced from the cryosolutions.
Geometric Model Describing the Banded Morphology of Particle Films Formed by Convective Assembly
Authors: Lee J. Alex , Reibel Kayla , Snyder Mark A. , Scriven L. E. , Tsapatsis Michael 
Published: July 2009

AbstractNanoparticle films coated on smooth substrates by convective assembly from dilute suspensions in dip‐coating configuration are known to have discrete film morphologies. Specifically, the film morphology is characterized by alternating bands of densely packed particles and bands of bare substrate. Convective assembly is a frontal film‐growth process that occurs at the three‐phase contact line formed by the substrate, the suspension in which it is submersed, and the surrounding air. The bands are parallel to this contact line and can be either monolayered or multilayered. Monolayered bands result whenever the substrate is withdrawn from the suspension at a rate too high for particles to assemble into a continuous film. We report a new insight to the mechanism behind this banding phenomenon, namely, that inter‐band spacing is strongly influenced by the constituent particle size. We therefore propose a geometric model relating the inter‐band spacing to the particle size. By making banded films with systematically varied particle sizes (silica/zeolite, 20 to 500 nm), we are able to quantitatively validate our model. Furthermore, the model correctly predicts that multilayered banded films have higher inter‐band spacings than monolayered banded films comprising the same particles.
Nanowire‐Based Polypyrrole Hierarchical Structures Synthesized by a Two‐Step Electrochemical Method
Authors: Ge Dongtao , Huang Sanqing , Qi Rucai , Mu Jing , Shen Yuqing , Shi Wei 
Published: July 2009

AbstractA simple two‐step electrochemical method is proposed for the synthesis of nanowire‐based polypyrrole hierarchical structures. In the first step, microstructured polypyrrole films are prepared by electropolymerization. Then, polypyrrole nanowires are electrodeposited on the surface of the as‐synthesized microstructured polypyrrole films. As a result, hierarchical structures of polypyrrole nanowires on polypyrrole microstructures are obtained. The surface wettabilities of the resulting nanowire‐based polypyrrole hierarchical structures are examined. It is expected that this two‐step method can be developed into a versatile route to produce nanowire‐based polypyrrole hierarchical structures with different morphologies and surface properties.
A reversed‐phase high‐performance liquid chromatography method for bovine serum albumin assay in pharmaceutical dosage forms and protein/antigen delivery systems
Authors: Hamidi Mehrdad , Zarei Najmeh 
Published: July 2009

AbstractBovine serum albumin (BSA) is among the most widely used proteins in protein formulations as well as in the development of novel delivery systems as a typical model for therapeutic/diagnostic proteins and the new versions of vaccines. The development of reliable and easily available assay methods for quantitation of this protein would therefore play a crucial role in these types of studies. A simple gradient reversed‐phase high‐performance liquid chromatography with ultra‐violet detection (HPLC‐UV) method has been developed for quantitation of BSA in dosage forms and protein delivery systems. The method produced linear responses throughout the wide BSA concentration range of 1 to 100 µ g/mL. The average within‐run and between‐run variations of the method within the linear concentration range of BSA were 2.46% and 2.20%, respectively, with accuracies of 104.49% and 104.58% for within‐run and between‐run samples, respectively. The limits of detection (LOD) and quantitation (LOQ) of the method were 0.5 and 1 µg/mL, respectively. The method showed acceptable system suitability indices, which enabled us to use it successfully during our particulate vaccine delivery research project. Copyright © 2009 John Wiley & Sons, Ltd.
Assignment of the Absolute Configuration ofConcentricolide– Absolute Configuration Determination of Its Bioactive Analogs Using DFT Methods
Authors: Ren Jie , Jiang Ju‐Xing , Li Liang‐Bo , Liao Tou‐Geng , Tian Ren‐Rong , Chen Xu‐lin , Jiang Si‐Ping , Pittman Charles U. , Zhu Hua‐Jie 
Published: July 2009

AbstractThe configuration ofconcentricolidewas assigned as (S). The configuration of its three analogs, which have anti‐HIV‐1 activity, were predicted by optical rotation values obtained by the B3LYP/aug‐cc‐pVDZ//B3LYP/6‐31+G(d) and B3LYP/aug‐cc‐pVDZ//MP2/6‐311+G(d) methods. The two methods predict very close optical rotation magnitudes for all three chiral analogs ofconcentricolide. The two methods were applied in optical rotation predictions for seven otherconcentricolideanalogs. Circular dichroism calculations were performed for four of the seven analogs at the B3LYP/aug‐cc‐pVDZ level.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
On modeling cluster maxima with applications to ozone data from Mexico City
Authors: Villaseñor‐Alva José A. , González‐Estrada Elizabeth 
Published: July 2009

AbstractThe study of the probability behavior of concentrations of air pollutants in the atmosphere is of great interest in order to take actions in favor of human health protection in large cities. This work proposes a parametric distributional model for the daily cluster maxima of concentrations exceeding a threshold, taking into consideration the dependence within the cluster. This model also provides a family of joint probability distributions for the maximum and the cluster size variables, which allows the study for prediction purposes of the conditional cluster size mean given that the cluster maximum does not exceed a particular value. The parameter estimation problem is discussed and a data set containing Mexico City ozone levels from the Summer seasons of years 2003 to 2007 is analyzed. Copyright © 2009 John Wiley & Sons, Ltd.
Modelling flow to and inundation of the Macquarie Marshes in arid Australia
Authors: Ren Shiquan , Kingsford Richard T. , Thomas Rachael F. 
Published: July 2009

AbstractBuilding of dams and subsequent abstraction upstream of rivers significantly affects major wetland systems. Knowledge of anthropogenic impacts of river regulation, relative to stochastic variation, is essential if managers are able to adequately manage flows to wetlands. We built annual flow and inundated area models for the Macquarie Marshes supplied by the Macquarie River, based on available annual rainfall data (1879–2006). We used LOESS, the flexible local polynomial regression method, ideal for modelling complex processes where no theoretical models exist. To compare effects of river regulation and abstraction, we developed two models, before river regulation (‘natural’ or ‘unregulated’) and after river regulation (‘regulated’). The division was when Burrendong dam, the most significant regulatory structure affecting flows, was built in 1963 and completed in 1967. After this point, water was diverted upstream, predominantly for irrigation. We developed ‘natural’ and ‘regulated’ flow models for three flow gauges Dubbo, Warren and Oxley based on annual rainfall at rainfall stations in the upper catchment and flow, and then inundated area models based on flow and local rainfall to fit annual inundated area data (1979–2006) in the Macquarie Marshes, using LOESS and leave‐one‐out samples without overfitting. We evaluated the performance of the proposed models and used these models to predict annual flows and inundated areas from 1879 to 2006. Comparison was done in terms of ‘natural’ and ‘regulated’ data using Kolmogorov–Smirnov test, identifying significant reductions in flow and wetland area. Copyright © 2009 John Wiley & Sons, Ltd.
Statistics for spatial functional data: some recent contributions
Authors: Delicado P. , Giraldo R. , Comas C. , Mateu J. 
Published: July 2009

AbstractFunctional data analysis (FDA) is a relatively new branch in statistics. Experiments where a complete function is observed for each individual give rise to functional data. In this work we focus on the case of functional data presenting spatial dependence. The three classic types of spatial data structures (geostatistical data, point patterns, and areal data) can be combined with functional data as it is shown in the examples of each situation provided here. We also review some contributions in the literature on spatial functional data. Copyright © 2009 John Wiley & Sons, Ltd.
Nonparametric test for separability of spatio‐temporal processes
Authors: Crujeiras Rosa M. , Fernández‐Casal Rubén , González‐Manteiga Wenceslao 
Published: July 2009

AbstractSpatio‐temporal correlated data are quite common in many fields, such as ecology, methereology or environmental science. In this situation, it is important to check the existence of spatio‐temporal interactions or on the contrary, if the spatial and temporal dependence components can be modelled independently. In this work, we propose a testing technique for detecting separability in the spatio‐temporal dependence structure. Our approach is based on the representation of the log‐periodogram as the response variable in a regression model. Within this context, separability can be interpreted as additivity in spatial and temporal frequency components. We also provide some simulation results comparing the performance of the asymptotic test with a marginal integration and a backfitting approach. The testing method is also applied to a real‐data case. Copyright © 2009 John Wiley & Sons, Ltd.
Compound optimal spatial designs
Authors: Müller Werner G. , Stehlík Milan 
Published: July 2009

AbstractA single purpose design may be quite inefficient for handling a real‐life problem. Therefore, we often need to incorporate more than one design criterion and a common approach is simply to construct a weighted average, which may depend upon different information matrices. Designs based upon this method have been termed compound designs. The need to satisfy more than one design criterion is particularly relevant in the context of random fields. It is evident that for precise universal kriging it is important not only to efficiently estimate the spatial trend parameters, but also the parameters of the variogram or covariance function. Both tasks could for instance be comprised by applying corresponding design criteria and constructing a compound design from there. Modern techniques for such first and second order characteristics will be suggested and reviewed in the presentation. A new hybrid stochastic exchange type optimization algorithm is proposed and an illustrating example of the design of a water‐quality monitoring network is provided. Copyright © 2009 John Wiley & Sons, Ltd.
Spatio‐temporal modeling of mortality risks using penalized splines
Authors: Ugarte M. D. , Goicoa T. , Militino A. F. 
Published: July 2009

AbstractAnalyzing the temporal evolution of the geographical distribution of mortality (or incidence) risks is an important area of research in disease mapping. It might help to better determining the risk factors involved in the studied disease, and to address important epidemiological questions about the stability of the estimated patterns of disease. Traditionally, risk smoothing is carried out using conditional autoregressive (CAR) models but very recently, penalized splines have also been considered in an Empirical Bayes (EB) spatial context to estimate large‐scale spatial trends together with region random effects. In this paper, penalized splines for smoothing risks in both the spatial and the temporal dimensions will be applied. The mean squared error (MSE) of the log‐risk predictor will be derived allowing for constructing confidence intervals for the risks. To illustrate the procedure mortality data due to brain cancer in continental Spain over the period 1996–;2005 are analyzed. Copyright © 2009 John Wiley & Sons, Ltd.
Derivation of sample oriented quantile function using maximum entropy and self‐determined probability weighted moments
Authors: Deng Jian , Pandey M. D. 
Published: July 2009

AbstractThe paper proposes a new distribution free method for deriving the quantile function of a non‐negative random variable using the principle of maximum entropy (MaxEnt) subject to constraints in terms of the self‐determined probability‐weighted moments estimated from observed sample data. The principle of MaxEnt constrained by probability weighted moments (PWMs) was utilized to estimate the quantile function. For correct estimation of a quantile function, outliers must be rationally considered in the analysis. However, conventional PWM was criticized for assigning non‐exceedance probabilities to sample points based on only their rank number in an ordered series rather than the magnitude of the points themselves, hereby being unable to satisfactorily accommodate outlier in a finite sample. The difficulty in obtaining accurate PWM estimates from samples has been the main impediment to the application of the MaxEnt Principle in extreme quantile estimation. This paper is an attempt to circumvent this difficulty by the use of self‐determined probability‐weighted moments, which are completely decided by the distribution itself and sample data's magnitude. By interpreting the SD‐PWM as moment of quantile function, the paper derives a more rigorous quantile function using MaxEnt principle, which is extraordinarily suitable for cases with small samples containing outliers. An efficient algorithm is presented to estimate the unknown parameters of this sample oriented MaxEnt QF. Comparative studies and numerical analysis are performed to assess the accuracy of the proposed QF estimation method. Copyright © 2009 John Wiley & Sons, Ltd.
Spatio‐temporal variations of hyporheic flow in a riffle‐step‐pool sequence
Authors: Käser Daniel H. , Binley Andrew , Heathwaite A. Louise , Krause Stefan 
Published: July 2009

AbstractSubsurface flow in streambeds can vary at different scales in time and space. Recognizing this variability is critical for understanding biogeochemical and ecological processes associated with the hyporheic zone. The aim of this study was to examine the variability of hydraulic conductivity (K), vertical hydraulic gradients (VHGs), and subsurface fluxes, over a riffle–step–pool sequence and at a high spatio‐temporal resolution. A 20 m reach was equipped with a network of piezometers in order to determine the distribution of VHGs and K. During a summer month, temporal variations of VHGs were regularly surveyed and, for a subset of piezometers, the water level was automatically recorded at 15 min intervals by logging pressure transducers. Additionally, point‐dilution tests were carried out on the same subset of piezometers. Whereas the distribution of vertical fluxes can be derived from K and VHG values, point‐dilution tests allow for the estimation of horizontal fluxes where no VHG is detectable. Results indicate that, spatially, VHGs switched from upwelling to downwelling across lateral as well as longitudinal sections of the channel. Vertical fluxes appeared spatially more homogeneous than VHGs, suggesting that the latter can be a poor indicator of the intensity of flow. Finally, during flow events, some VHGs showed little or no fluctuations; this was interpreted as the result of a pressure wave propagating from upstream through highly diffusive alluvial sediments. Copyright © 2009 John Wiley & Sons, Ltd.
Network ties and mean lies: a relational approach to relational aggression
Authors: Neal Jennifer Watling 
Published: July 2009

AbstractThe current study considers how the structure of peer networks facilitates or constrains children's opportunities to engage in relationally aggressive behaviors such as social exclusion and rumor spreading. Specifically, the influence of two network features, centrality and density, on relational aggression are explored using grade‐level behavioral and social network data collected on a demographically diverse sample of 144 third through eighth grade urban elementary school students. As hypothesized, these network features influenced levels of teacher‐rated and peer‐nominated relational aggression beyond the effects of demographic characteristics (i.e., gender and grade). Results revealed that relational aggression is influenced not only by who children are, but also by where they are located in the peer context. Implications for future research and intervention are offered. © 2009 Wiley Periodicals, Inc.
Highly efficient and organic nitrogen‐containing cation‐promoted aerobic oxidation of alkylaromatics in the presence of N‐hydroxyphthalimide
Authors: Tong Xinli , Xu Jie , Miao Hong , Gao Jin , Sun Zhiqiang , Zhang Wei 
Published: July 2009

AbstractBACKGROUD: Direct oxidation of alkylaromatics to the corresponding aromatic ketone is an important process in the manufacture of perfumes, pharmaceuticals, flavors, dyes and agrochemicals. For example, tetralin is oxidized to produce 1‐tetralinone, which is a key intermediate in the commercial production of 1‐naphthol, 2‐hydroxy‐1‐tetralone, aureolic acid antibiotics and other pharmaceuticals.RESULTS: In this investigation, it was found that alkylaromatics could be efficiently and selectively oxidized to the corresponding aromatic ketones when methyl violet was employed as a promotor in the presence of N‐hydroxyphthalimide (NHPI); tetralin was oxidized with 89% conversion and 76% selectivity to 1‐tetralinone under 0.3 MPa of O2 at 75 °C for 2.5 h. The effects of temperature, oxygen pressure, reaction time and additive inclusion were studied in detail. A possible reaction mechanism for tetralin oxidation has been proposed.CONCLUSION: It was demonstrated that methyl violet could efficiently promote the aerobic oxidation of alkylaromatics in the presence of NHPI under mild conditions. Further investigations indicated that the nitrogen cation had a crucial promotion effect in the oxidation process. Copyright © 2009 Society of Chemical Industry
Synthesis of [3‐13C]‐, [4‐13C]‐ and [11‐13C]‐porphobilinogen
Authors: Dawadi Prativa B. S. , Schulten Els A. M. , Lugtenburg Johan 
Published: July 2009

Abstract[4‐13C]‐porphobilinogen 1a, [3‐13C]‐porphobilinogen 1b and [11‐13C]‐porphobilinogen 1c are prepared from [1‐13C]‐3‐(tetrahydropyran‐2′‐yloxy)‐propionaldehyde 2a, methyl [4‐13C]‐4‐nitrobutyrate 3b and [1‐13C]‐isocyanoacetonitrile 5c, respectively. The building blocks 2, 3 and 5 can be prepared efficiently in any isotopomeric form. Via base‐catalyzed condensation of these building blocks porphobilinogen can be enriched with 13C and 15N stable isotopes at any position and combination of positions. Copyright © 2009 John Wiley & Sons, Ltd.
The first synthesis of [11C]oseltamivir: a tool for elucidating the relationship between Tamiflu and its adverse effects on the central nervous system
Authors: Arai Takuya , Konno Fujiko , Ogawa Masanao , Zhang Ming‐Rong , Suzuki Kazutoshi 
Published: July 2009

AbstractOseltamivir phosphate (Tamiflu®) is an anti‐influenza drug approved in many countries. Recently, in Japan, adverse effects on the central nervous system have been reported in younger patients administrated with Tamiflu. As a tool for elucidating the relationship between Tamiflu and its adverse effects, 11C‐labeled oseltamivir was synthesized through a two‐step reaction involving [11C]acetylation with [1‐11C]acetyl chloride. Starting from approximately 37.0 GBq of [11C]CO2, 1.2–1.8 GBq (n=5) of [11C]oseltamivir was obtained at the end of synthesis (EOS) 36–39 min after the end of bombardment. Radiochemical purity and specific activity were greater than 98% and 2.7–6.3 GBq/µmol at EOS, respectively. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis of three isotopically labeled versions and a metabolite of Aurora A kinase inhibitor
Authors: Li Yuexian , Prakash Shimoga R. 
Published: July 2009

AbstractSodium ring‐[14C]‐4‐[[9‐chloro‐7‐(2,6‐difluorophenyl)‐5H‐pyrimido[5,4‐d][2]benzazepin‐2‐yl]amino]‐benzoate (1A, MLN8054), an Aurora A kinase inhibitor, was synthesized from [14C]‐cyanamide in two steps in an overall radiochemical yield of 7%. The intermediate, [14C]‐4‐guanidinobenzoic acid, was prepared by coupling [14C]‐cyanamide with 4‐aminobenzoic acid. Sodium carboxyl‐[14C]‐4‐[[9‐chloro‐7‐(2,6‐difluorophenyl)‐5H‐pyrimido[5,4‐d][2]benzazepin‐2‐yl]amino]‐benzoate (1B) was synthesized from carboxyl‐[14C]‐4‐guanidinobenzoic acid in one step in a radiochemical yield of 35%. [D4,15N]‐4‐[[9‐chloro‐7‐(2,6‐difluorophenyl)‐5H‐pyrimido[5,4‐d][2]benzazepin‐2‐yl]amino]‐benzoic acid (1C) was synthesized from [15N2]‐cyanamide and [D4]‐4‐aminobenzoic acid in two steps in an overall yield of 37%. The major metabolite, β‐acyl glucuronide of 4‐[[9‐chloro‐7‐(2,6‐difluorophenyl)‐5H‐pyrimido[5,4‐d][2]benzazepin‐2‐yl]amino]‐benzoic acid (14), was synthesized from D‐glucuronic acid in three steps in an overall yield of 1%. The key intermediate for synthesis of glucuronide was prepared by HATU catalyzed coupling of 4‐[[9‐chloro‐7‐(2,6‐difluorophenyl)‐5H‐pyrimido[5,4‐d][2]benzazepin‐2‐yl]amino]‐benzoic acid with allyl glucuronate. Copyright © 2009 John Wiley & Sons, Ltd.
Raman spectroscopy and security applications: the detection of explosives and precursors on clothing
Authors: Ali Esam M. A. , Edwards Howell G. M. , Scowen Ian J. 
Published: July 2009

AbstractThis study describes the application of confocal Raman microscopy to the detection and identification of explosives and their precursors in situ on undyed natural and synthetic fibres and coloured textile specimens. Raman spectra were obtained from explosives particles trapped between the fibres of the specimens. The explosives pentaerythritol tetranitrate (PETN), trinitrotoluene (TNT), and ammonium nitrate as well as the explosives precursors hexamethylenetetraamine (HMTA) and pentaerythritol were used in this study. Raman spectra were collected from explosives particles with maximum dimensions in the range 5–10 µm. Despite the presence of spectral bands arising from the natural and synthetic polymers and dyed textiles, the explosive substances could be identified by their characteristic Raman bands. Furthermore, Raman spectra were obtained from explosives particles trapped between highly fluorescent clothing fibres. Raman spectra of the explosive and explosive precursor substances on dyed and undyed clothing substrates were readily obtained in situ within 90 s without sample preparation and with no alteration of the evidential material. Copyright © 2009 John Wiley & Sons, Ltd.