bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protonolysis Reactions of [(Me3Si)2N]3Ln(μ‐Cl)Li(thf)3 with tBuSH or EtSH: Isolation, Structures and Catalytic Properties of Dinuclear Complexes [{(Me3Si)2N}2Ln(μ‐StBu)]2 and Tetranuclear Complexes [Li(thf)4][{(Me3Si)2N}4Ln4(μ4‐SEt)(μ‐SEt)8] (Ln = Pr, Sm)
Authors: Cheng Mei‐Ling , Li Hong‐Xi , Zhang Wen‐Hua , Ren Zhi‐Gang , Zhang Yong , Lang Jian‐Ping 
Published: March 2007

AbstractReactions of [(Me3Si)2N]3Ln(μ‐Cl)Li(thf)3 (1: Ln = Pr; 2: Ln = Sm) with an equimolar amount of tBuSH or EtSH gave rise to four amidolanthanide alkylthiolate complexes [{(Me3Si)2N}2Ln(μ‐StBu)]2 (3: Ln = Pr; 4: Ln = Sm) and [Li(thf)4][{(Me3Si)2N}4Ln4(μ4‐SEt)(μ‐SEt)8] (5: Ln = Pr; 6: Ln = Sm). Compounds 3–6 were characterized by elemental analysis, IR and 1H NMR spectroscopy and single‐crystal X‐ray diffraction, and their catalytic properties were also investigated. Compounds 3 and 4 are thiolate‐bridged dimers in which each Ln atom adopts a distorted tetrahedral coordination. Compounds 5 and 6 contain a Ln4 square plane, which is capped by a μ4‐SEt– ligand. The edges of the square are bridged by four pairs of SEt– ligands on both sides of the Ln4 plane. Each Ln atom has a distorted octahedral geometry. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Seismic response due to travelling shear wave including soil‐structure interaction with base‐mat uplift
Authors: Wolf J. P. 
Published: March 2007

AbstractThe seismic response due to a travelling shear wave is investigated. The resulting input consists of a translational‐and a torsional‐acceleration time history, which depend on the ratio of the wavelength to the dimension of the footing. A nuclear reactor building is used for illustration. The combined result of the translational and torsional elastic response (the latter arises even in an axisymmetric structure) will not, in general, be larger than that encountered in the case of a spatially uniform earthquake. If the footing slips or becomes partially separated from the soil, a non‐linear dynamic analysis has to be performed to determine the response. Substantial motions in all three directions will take place. The peak structural responses and the floor‐response spectra are found to be highly non‐linear for high acceleration input values.
Response of circular bridge decks to moving vehicles
Authors: Ramakrishnan R. , Kunukkasseril V. X. 
Published: March 2007

AbstractThis paper discusses the dynamic response of a curved bridge deck to a moving vehicle. The bridge deck is idealized as a set of annular sector plates and circular rings rigidly jointed together. On the basis of classical plate and ring theories a method has been developed to obtain the response to a moving vehicle idealized as a spring mass system. After obtaining the normal modes and frequencies and establishing the orthogonality conditions, the problem of the forced motion of the deck is solved by the method of spectral representation. Numerical results have been presented to illustrate the effect of several vehicle and bridge parameters on the response.
Empirical shear wave velocity equations in terms of characteristic soil indexes
Authors: Ohta Yutaka , Goto Noritoshi 
Published: March 2007

AbstractAn investigation to systematize empirical equations for the shear wave velocity of soils was made in terms of four characteristic indexes. The adopted indexes are the N‐value of the Standard Penetration Test, depth where the soil is situated, geological epoch and soil type. As some of these indexes are variates belonging to interval scales while others belong to nominal or ordinal scales, the technique known as a multivariate analysis cannot be employed. A new approach to the theory of quantification, after C. Hayashi, was introduced and developed for solving this difficulty.Fifteen sets of empirical equations to estimate low strain shear wave velocity theoretically may be obtained by combining the above four indexes. All of these sets were derived by use of about 300 data, and their accuracies were evaluated by means of correlation coefficients between the measured and estimated shear wave velocities. The best equation was found to be the one which included all the indexes, and its correlation coefficient was 0.86. The empirical equation relating the standard penetration N‐value to the shear wave velocity provided a correlation of only 0.72, and is one of the lowest ranking among the 15 sets of equations.
A mathematical model to predict the inelastic response of a steel frame: Formulation of the model
Authors: McNiven Hugh D. , Matzen Vernon C. 
Published: March 2007

AbstractThe purpose of this research is to use data from experiments to formulate a mathematical model that will predict the non‐linear response of a single‐storey steel frame to an earthquake input. The process used in this formulation is system identification.The form of the model is a second‐order non‐linear differential equation with linear viscous damping and Ramberg—Osgood type hysteresis. The damping coefficient and the three parameters in the hysteretic model are to be established. An integral weighted mean squared error function is used to evaluate the [goodness of fit] between the model's response and the structure's response when both are subjected to the same excitation. The function includes errors in displacement and acceleration and is integrated from zero to a time T, which may be the full duration of the recorded response or only a portion of it. The parameters are adjusted using a modified Gauss‐Newton method until the error function is minimized.The computer program incorporating these steps in the system identification process is verified with simulated data. Results given in the paper show that in every case the program converges in few iterations to the assigned set of parameters.
The vibrational characteristics of a twelve‐storey steel frame building
Authors: Foutch Dougla S. A. 
Published: March 2007

AbstractThe Ralph M. Parsons World Headquarters building, a twelve‐storey steel frame structure, was subjected to a series of forced vibration tests. The natural frequencies, three‐dimensional mode shapes and damping coefficients of nine modes of vibration were determined. Other features of this investigation included the study of non‐linearities associated with increasing levels of response, detailed measurements of the deformation of the first floor and the ground surrounding the structure, and measurements of strain in one of the columns of the structure during forced excitation.The dynamic characteristics of the building determined by these tests are compared to those predicted by a finite element model of the structure. The properties of primarily translational modes are predicted reasonably well, but adequate prediction of torsional motions is not obtained. The comparison between measured and predicted strains suggests that estimates of stress determined from finite element analyses of buildings might be within 25 per cent of those experienced by the structure for a known excitation.
Natural vibrations of shear wall buildings on flexible supports
Authors: Coull A. , Mukherjee P. R. 
Published: March 2007

AbstractA shear wall building is considered as an assembly of plane and curvilinear shear walls tied together by floor slabs to act as a composite unit. Based on this conception and the continuous medium approach, the governing dynamic equations and boundary conditions are derived from energy principles, using Vlasov's theory of thin‐walled beams. All primary and secondary inertia forces, as well as the influence of elastic foundation flexibility, have been taken into consideration. A numerical solution of the dynamic equations is achieved by employing the Ritz‐Galerkin technique, yielding both natural frequencies and mode shapes. The technique is applicable to buildings containing coupled and non‐coupled, open section shear walls oriented in plan in any arbitrary manner. The use of the method is illustrated by the example of a complex building with unsymmetric plan, and the analytical natural frequencies of two shear wall building models are compared with those obtained experimentally by other investigators.
Monetary valuation of informal care: the well‐being valuation method
Authors: van den Berg Bernard , Ferrer‐i‐Carbonell Ada 
Published: March 2007

AbstractThis paper estimates the monetary value of providing informal care by means of a well‐being valuation method. This is done by assessing the compensating variation necessary to maintain the same level of well‐being after an informal caregiver provides an extra hour of informal care. The informal caregiver's well‐being is proxied by the answer to two subjective well‐being questions that were posed in a questionnaire answered by 865 Dutch informal caregivers between the end of 2001 and the beginning of 2002. In the econometric analysis, a distinction is made between the care recipients who are and the ones who are not a family member of the informal caregiver. The results indicate that an extra hour of informal care is worth about 9 or 10 Euros. This equals 8 or 9 Euros if the care recipient is a family member and about 7 or 9 Euros if not. When applying the contingent valuation method to the same sample, the value obtained was 10.52 Euros per hour. This paper concludes that the well‐being valuation method is a useful complement to the more traditional valuation methods in the health economics literature in general and more particularly for the economic valuation of informal care: it includes all costs and effects associated with providing care from the perspective of the informal caregiver, it is relatively cheap to implement, and it offers an additional possibility to determine the convergent validity of the different monetary valuation methods. Copyright © 2007 John Wiley & Sons, Ltd.
Influence of cyclodextrins on the proliferation of HaCaT keratinocytes in vitro
Authors: Hipler U.C. , Schönfelder U. , Hipler C. , Elsner P. 
Published: March 2007

AbstractSafety and efficacy of pharmaceutical agents can be greatly improved by encapsulation within, or covalent attachment to, a biomaterial carrier. Drug delivery systems must deliver the necessary amount of drug to the targeted site for a necessary period of time, both efficiently and precisely. Various kinds of high‐performance biomaterials are being constantly developed for this purpose. Cyclodextrins are potential candidates for such a role, because of their ability to alter physical, chemical, and biological properties of guest molecules through the formation of inclusion complexes. The α‐, β‐, and γ‐cyclodextrins are widely used natural cyclodextrins, consisting of six, seven, and eight D‐glucopyranose residues, respectively, linked by ‐1,4 glycosidic bonds into a macro cycle. Each cyclodextrin has its own ability to form inclusion complexes with specific guests, an ability, which depends on a proper fit of the guest molecule into the hydrophobic cyclodextrin cavity. The most common pharmaceutical application of cyclodextrins is to enhance the solubility, stability, and bioavailability of drug molecules. Such kinds of ligand–receptor complexes can be used for different applications, e.g., for a transdermal therapeutic system (TTS) or in biofunctional textiles. The aim of this study was the investigation of the influence of the different cyclodextrins on the cell proliferation using HaCaT keratinocytes as an in vitro test system. Moreover, the study was performed to find harmless and nontoxic cyclodextrin concentrations for dermal applications. By means of different independent in vitro tests could be confirmed that α‐, β‐, and γ‐cyclodextrins in concentrations up to 0.1% (w/v) do not show any antiproliferative influence on HaCaT keratinocytes. Sometimes even proliferative effects could be found. However, all used cyclodextrins (besides γ‐cyclodextrin and its derivatives) in concentrations of 0.5 and 1% (w/v), respectively, exert a cytotoxic influence on the proliferation of HaCaT keratinocytes. On the basis of these findings, the following rank order of cyclodextrins regarding their cytotoxicity was proposed: M‐β‐CD ≫ β‐CD ≫ HP‐β‐CD ≫ α‐CD ≫ (γ‐CD). It could be confirmed that β‐CD and M‐β‐CD trigger the activity of the effectors caspases ‐3 and ‐7. A significant increase of LDH release could be found for β‐CD and methyl‐β‐CD in concentrations of 0.5 and 1% (w/v). The calculated cytotoxicity amounted 45 and 79%, respectively. The measurements of the interleukins IL‐6 and IL‐8 confirmed the findings of the proliferation assays as well as the LDH measurements. These findings may provide further rationale to the use of CDs in topical formulations for dermal and transdermal drug delivery or as raw material to functionalize textiles for medical applications. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Gene delivery to airway epithelial cells in vivo: a direct comparison of apical and basolateral transduction strategies using pseudotyped lentivirus vectors
Authors: Kremer Karlea L. , Dunning Kylie R. , Parsons David W. , Anson Donald S. 
Published: March 2007

AbstractLentivirus vectors are being investigated as gene delivery vehicles for cystic fibrosis airway gene therapy. Vesicular stomatitis virus G glycoprotein (VSV‐G)‐pseudotyped vectors transduce airway epithelia via receptors that are located predominantly on the basolateral surface of the airway epithelium. Effective transduction with VSV‐G‐pseudotyped vectors requires the use of a pre‐treatment that disrupts epithelial tight junctions, allowing access to these basolateral receptors. In contrast, it has been reported that apically targeted lentiviral vectors allow efficient gene transfer in the absence of any pre‐treatment. In a direct comparison of transduction by a VSV‐G‐pseudotyped vector, in combination with a pre‐treatment with lysophosphatidylcholine (LPC), and the same vector pseudotyped with the apically targeted baculovirus GP64 envelope (without any pre‐treatment), the GP64 vector was found to be significantly less efficient. However, when a pre‐treatment with LPC was used the level of transduction with the GP64‐pseudotyped lentiviral vector was not significantly different to that resulting from the VSV‐G‐pseudotyped vector. The cell types transduced with each vector were essentially the same, with the majority of cells transduced being respiratory (ciliated cells). However, unlike the VSV‐G‐pseudotyped vector, which results in persisting gene expression, transduction with the GP64‐pseudotyped vector resulted in gene expression that declined to undetectable levels over six months, whether or not an LPC pre‐treatment was used. Copyright © 2007 John Wiley & Sons, Ltd.
Diffusion and perfusion magnetic resonance imaging of the evolution of hypoxic ischemic encephalopathy in the neonatal rabbit
Authors: D'Arceuil Helen E. , de Crespigny Alex J. , Röther Joachim , Seri Shigemi , Moseley Michael E. , Stevenson David K. , Rhine William 
Published: March 2007

AbstractHypoxic‐ischemic encephalopathy (HIE) can result from neonatal asphyxia, the pathophysiology of which is poorly understood. We studied the acute evolution of this disease, using magnetic resonance imaging in an established animal model. HIE was induced in neonatal rabbits by a combination of common carotid artery (CCA) ligation and hypoxia. Serial diffusion and perfusion‐weighted magnetic resonance images were acquired before, during, and after the hypoxic interval. Focal areas of decreased apparent diffusion coefficient (ADC) were detected initially in the cortex ipsilateral to CCA ligation within 62 ± 48 min from the onset of hypoxia. Subsequently, these areas of decreased ADC spread to the subcortical white matter, basal ganglia (ipsilateral side), and then to the contralateral side. Corresponding perfusion‐weighted images showed relative cerebral blood volume deficits which closely matched those regions of ADC change. Our results show that MRI diffusion and perfusion‐weighted imaging can detect acute cell swelling post‐hypoxia in this HIE model.
1H MRS in acute traumatic brain injury
Authors: Ross Brian D. , Ernst Thomas , Kreis Roland , Haseler Luke J. , Bayer Stefan , Danielsen Else , Blüml Stefan , Shonk Truda , Mandigo Jennifer C. , Caton William , Clark Christopher , Jensen Steen W. , Lehman Norman L. , Arcinue Edgardo , Pudenz Robert , Shelden C. Hunter 
Published: March 2007

AbstractThe objective of this study was to demonstrate 1H MR spectroscopy (MRS) changes in cerebral metabolites after acute head trauma. Twenty‐five patients (12 children, 13 adults) were examined with quantitative 1H MRS after closed head injury. Clinical grade (Glasgow Coma Scale [GCS]) and outcome (Rancho Los Amigos Medical Center Outcome Score [ROS]) were correlated with quantitative neurochemical findings. N‐acetylas‐partate (NAA), a neuronal and axonal marker, was reduced (P < .03−.001). In children, a reduced NAA/creatine plus phosphocreatine (Cr) level and the presence of detectable lipid/lactate predicted bad outcome (sensitivity, 89%; specificity, 89%). The first MRS examination of all patients correlated with ROS versus NAA (r = .65, P < .0001). Although most patients showed MRS abnormalities, striking heterogeneity of 1H MRS characterized the individual patients. 1H MRS identifies multiple patterns of diffuse brain injury after blunt head trauma. There was a strong correlation between MRS and outcome. Future prospective studies will be needed to determine the clinical usefulness of MRS in predicting outcome from closed head injury.
Neural network for the estimation of UV erythemal irradiance using solar broadband irradiance
Authors: Alados I. , Gomera M. A. , Foyo‐Moreno I. , Alados‐Arboledas L. 
Published: March 2007

AbstractIn recent years there has been a substantial increase in attempts to model radiative flux of ultraviolet radiation, UV. In this paper we present the development of an artificial neural network (ANN) model that can be used to estimate solar UV erythemal irradiance, UVER, based on optical air mass, ozone columnar content and broadband solar irradiance. The study was developed at seven stations in the Iberian Peninsula using data recorded at A Coruña, Málaga, Murcia and Santander, during 2000–2003; at Madrid in the period 2000–2002; at Valencia in 2000, 2001 and 2003; and at Zaragoza, from 2001 to 2003. The UVER observations are recorded as half‐hour average values. The measurements were performed in the framework of the Spanish UV‐B radiometric network operated and maintained by the Spanish Meteorological Institute. In order to train and validate the Multi‐layer Perceptron neural networks, independent subsets of data were extracted from the complete database at each station. The networks developed at each place when applied to an independent data set recorded at the same location provide estimates with mean bias deviation less than 1% and root mean square deviation below 17% for all the sites. The generalization network developed using data registered at A Coruña, Madrid, Murcia and Zaragoza provides estimates at all the locations with RMSD below 19%. According to these results, the use of solar broadband irradiances for the estimation of ultraviolet erythemal irradiance provides a tool that can solve the difficulties associated to the retrieval of appropriate information on the cloud field by human observers. In this sense, the proposed method seems appropriate to use the widespread networks of solar broadband irradiance to obtain ultraviolet erythemal irradiance data sets in places where this radiative flux is not measured or to extend back in time the existing data sets. Copyright © 2007 Royal Meteorological Society
Assembly of Polyelectrolytes on CNTs by Van der Waals Interactions and Fabrication of LBL Polyelectrolyte/CNT Composites
Authors: Moya Sergio E. , Ilie Adelina , Bendall James S. , Hernandez‐Lopez Jose L. , Ruiz‐García Jaime , Huck Wilhelm T. S. 
Published: March 2007

AbstractWe have successfully coated CNTs with either positively or negatively charged polyelectrolytes employing Van der Waals interactions between nanotubes and polyelectrolyte molecules, without any previous chemical modification of the nanotubes walls. Polymer adsorption of polyelectrolytes was performed in an ethanolic solution, followed by redispersion in water. The surface coating was verified with ζ‐potential measurements and SEM. A sequential assembly of polyelectrolyte layers on top of the polyelectrolyte modified nanotubes has been achieved from a water solution following the layer‐by‐layer technique. The assembly of polyelectrolytes from water on CNTs deposited on a surface has also been shown with QCM‐D. Then, polyelectrolyte coated CNTs have been used as positive and negative blocks in the templating of layer‐by‐layer films.magnified image
Description of an advanced practice nursing consultative model to reduce restrictive siderail use in nursing homes
Authors: Wagner Laura M. , Capezuti Elizabeth , Brush Barbara , Boltz Marie , Renz Susan , Talerico Karen A. 
Published: March 2007

AbstractResearchers have demonstrated that the use of physical restraints in nursing homes can be reduced, particularly where advanced practice nurses (APNs) are utilized. We examined the link between APN practice, siderail reduction, and the costs of siderail alternatives in 273 residents in four Philadelphia nursing homes. The majority of participants were cognitively and physically impaired with multiple co‐morbidities. APNs recommended a total of 1,275 siderail‐alternative interventions aimed at reducing fall risk. The median cost of siderail alternatives to prevent falls per resident was $135. Residents with a fall history experienced a significantly higher cost of recommendation compared to non‐fallers. Findings suggest that an APN consultation model can effectively be implemented through comprehensive, individualized assessment without incurring substantial costs to the nursing home. © 2007 Wiley Periodicals, Inc. Res Nurs Health 30: 131–140, 2007
Structural causes of the dyeing variations of nylon yarns subjected to steam heat
Authors: Warwicker J. O. 
Published: March 2007

AbstractNylon 6 and nylon 6.6 yarns were subjected to wet heat in a relaxed state and the subsequent rate of dyeing of these yarns with Durazol Blue 2R was then studied. The rate of dyeing progressively increased as the temperature of steaming increased. For nylon 6 this increase in rate of dyeing was almost eightfold in heating up to 140°C compared with that of unheated samples; for nylon 6.6 the increase was threefold after heating in steam at 150°C. It was confirmed that Fick's law is still valid for describing the dyeing process with nylon 6.6 but not with nylon 6. Measurements of density, birefringence, X‐ray orientation and degree of lateral order by an X‐ray method show that these are all increased by the steam treatments. There is little change in the moisture regain and amine end‐group content. An explanation of these observations is advanced in terms of a morphology that allows an increase in the size, shape or quantity of voids on heating the polyamides in steam.
Application of the modified avrami equations to polymer crystallisation kinetics
Authors: Hay J. N. 
Published: March 2007

AbstractExplanations of the deviations of polymer crystallisation isotherms from Avrami equations are considered in the light of the assumptions inherent in the derivation of the equations and analysis of the crystallisation isotherms; these explanations are rejected. Modified equations which allow for the presence of several crystallisation mechanisms and recrystallisation are considered to be a more satisfactory physical model of spherulitic crystallisation from the melt. While they describe the crystallisation isotherms more accurately than a single Avrami process, non‐random deviations which cannot be satisfactorily explained still exist. Further modifications to include changing nucleation characteristics, induction periods, etc., do not improve the fit of these modified equations.