bluuebunny/crossref_metadata_2025 huggingface dataset:
Raman and Wide‐Angle X‐Ray Diffraction Studies on Molecular Structure, Crystallinity, and Morphology of Uncompatibilized and Compatibilized Blends of High Molecular Weight Polyethylene/Nylon 12
Authors: Sato Harumi , Isogai Misayo , Sasao Shigehiro , Matsukawa Kimihiro , Kita Yasuo , Yamaguchi Hiroshi , Siesler Heinz W. , Ozaki Yukihiro
Published: January 2005

Molecular structure, crystallinity and morphology of uncompatibilized and compatibilized blends of high molecular weight polyethylene (HMWPE) and Nylon 12 were investigated by using Fourier‐transform (FT) Raman spectroscopy, wide‐angle x‐ray diffraction (WAXD), and scanning electron microscopy (SEM). One of the important purposes of the present study is to compare the present results for HMWPE/Nylon 12 with the previously obtained results for high‐density polyethylene (HDPE/Nylon 12). Uncompatibilized and compatibilized blends of HMWPE/Nylon 12 with a Nylon 12 content ranging from 10 to 90 wt% at increments of 10 wt% were prepared. The compatibilized polymer blends were prepared by adding a small amount of maleic anhydride (MAH), and SEM images show that the addition of the small amount of MAH (0.5 wt%) yields a marked improvement of dispersion of HMWPE and Nylon 12. To evaluate the crystallinity of HMWPE from Raman spectra, the relative intensities of bands at 1418 and 1129 cm−1 to the intensity of a band at 1000 cm−1 (I1418/I1000 and I1129/I1000) were estimated for all the uncompatibilized and compatibilized blends of HMWPE/Nylon 12. From the comparison of the relative intensities (I1418/I1000 and I1129/I1000) between the uncompatibilized and compatibilized blends of HMWPE/Nylon 12 it was found that when the Nylon 12 content reaches 40 wt% the crystallinity of HMWPE in the compatibilized blends becomes higher than that of HMWPE in the uncompatibilized blends. The uncompatibilized and compatibilized blends of HMWPE/Nylon 12 (50/50) show quite different x‐ray diffraction patterns; the compatibilized blend shows a significantly larger orientational effect in the x‐ray pattern of HMWPE. It seems that the increase of interaction of MAH‐HMWPE with the Nylon 12 matrix leads to the additional crystallinity.
Study of Molecular Orientation by Vibrational Spectroscopy: From Polymers to Silk
Authors: Pellerin Christian , Rousseau Marie‐Eve , Côté Mathieu , Pézolet Michel
Published: January 2005

Infrared and Raman spectroscopies are very efficient techniques to characterize molecular orientation in macromolecular systems. In the present paper, two examples of the application of vibrational spectroscopy to the study of molecular orientation in synthetic and natural macromolecules will be presented. In the first example, the dynamics of orientation and relaxation of stretched films of bimodal blends of polystyrene (PS) and deuterated polystyrene (dPS) has been studied in situ by polarization modulation infrared linear dichroism while, in the second one, polarized Raman microspectroscopy has been used to determined quantitatively the orientation of β‐sheet domains in single filaments of Bombyx mori silk.
NMR as a Probe into the Local and Semilocal Order in Cooperative Interactions of Polyelectrolytes
Authors: Kříž Jaroslav
Published: January 2005

Polyelectrolytes such as poly(N‐diallyldimethylammonium chloride) (PDADMAC) exhibit some local and semilocal order both in their conformation dynamics (dynamic correlations) and the average density of their counterion cloud (the radial density distribution). Both aspects of order are subject to cooperative fluctuations as well as mutual reinforcement. They can be observed in particular in dilute solutions, i.e. at concentrations of the charged groups less than 5 mmol/L. At such dilution, 1H NMR is the method of choice for the study of conformation dynamics. In addition to the recently published analysis of transverse relaxation and saturation transfer experiments, relaxations of double‐quantum coherence, pseudo‐solid echo and solid echo responses and exchange 2D spectra are reported here. For the radial distribution of counterions with spin‐3/2 nuclei (7Li, 23Na, 35Cl, 81Br), the relaxation model proposed by Halle, Wennerstrom and Picullel is applied and the use of either combined longitudinal and transverse relaxation or DQC (T23) relaxation is shown. The results show that the counterion condensation, i.e. relative ordering of the counterion cloud, decreases in less densely charged polyions and vanishes for the charge separation about 2.5 nm.
Shear‐Induced Order in Nematic Polymers
Authors: Becker Patrick , Siebert Hartmut , Noirez Laurence , Schmidt Claudia
Published: January 2005

Several nematic side‐chain polysiloxanes with the same backbone and the same mesogens but containing various ratios of two spacers having different lengths were prepared. Within this series of homo‐ and copolymers, the phase behavior changes continuously from purely nematic for the homopolymer containing only the shorter of the two spacers to nematic plus smectic for the homopolymer containing only the longer spacer. The flow behavior determined by in situ deuterium NMR spectroscopy under shear and the anisotropy of the coil conformation measured by small angle neutron scattering exhibit a continuous change as well.
Vibrational Spectroscopy of Ion Irradiated Carbon Containing Macromolecules
Authors: Strazzulla Giovanni , Baratta Giuseppe , Brunetto Rosario , Cataldo Franco
Published: January 2005

A large variety of carbon rich macromolecules has been studied in our laboratory, before, during, and after ion irradiation (3‐60 keV ions), by in situ IR and Raman spectroscopies. In this paper we present results obtained on: (a) Films of frozen H2O:CH4:N2 mixtures that have been deposited at low temperature (12 K) on a silicon substrate, and irradiated with fast ions. Irradiation causes the formation of organic refractory residues whose spectra have been recorded and studied also after further irradiation at room temperature. (b) Pentacene (a Polyciclic Aromatic Hydrocarbon, PAH) whose Raman spectra have been studied also during ion irradiation at room temperature. (c) Thin samples of fullerene (C60) films also irradiated at room temperature.

Here we discuss some of the most relevant results and compare the spectra of the very different samples that after prolonged irradiation, evolve towards amorphous carbons that have common spectral characteristic. The results are discussed in terms of their astrophysical relevance. It is demonstrated that frozen hydrocarbons, PAHs and fullerenes are rapidly converted to amorphous carbon in space. Amorphous carbon has to be a widespread material in many astrophysical environments.
Structure elucidation and complete NMR spectral assignments of a new benzoxazolinone glucoside from Acanthus ilicifolius
Authors: Huo Changhong , An Dongge , Wang Bin , Zhao Yuying , Lin Wenhan
Published: January 2005

A new benzoxazolinone glucoside, 4‐O‐β‐D‐glucopyranosyl‐benzoxazolin‐2(3H)‐one, was isolated from Acanthus ilicifolius, a medicinal plant from south China. The complete 1H and 13C NMR assignments of the compound were carried out by using DEPT, HMBC, HMQC, NOESY and 1H1H COSY spectra. Copyright © 2005 John Wiley & Sons, Ltd.
Study of the behaviour of amino acids in aqueous solution by time‐domain NMR and high‐resolution NMR
Authors: Khallouk M. , Rutledge D. N. , Silva A. M. S. , Delgadillo I.
Published: January 2005

The study of protein hydration by time‐domain NMR is complicated by the great number of interactions involved, resulting from the presence of several amino acids and the possible modifications produced by the various structures. Moreover, a good comprehension of the molecular interactions of the simple amino acids in solution is essential to elucidate the mechanism of the biological functions of proteins. Measurements of transverse relaxation rates of the protons of water (R2 = 1/T2) in aqueous solutions of amino acids such as L‐glycine, L‐asparagine, L‐arginine and L‐tryptophan were carried out in order to study the effects of chemical exchange and molecular diffusion on the amplitude of R2. The values of R2 measured by the Carr–Purcell–Meiboom–Gill (CPMG) sequence were studied while varying the solution pH and the parameters of the CPMG sequence. The dependence of R2 on pH and τ (inter‐pulse delay between the first and the second pulses of the CPMG sequence) is interpreted in terms of chemical exchange between the protons of water and those of the labile amino acid groups. This interpretation was confirmed by the analysis of the proton spectra acquired using a 300 MHz NMR spectrometer. Copyright © 2005 John Wiley & Sons, Ltd.
Measurement of 1J(Ni,Cαi), 1J(Ni,C′i−1), 2J(Ni,Cαi−1), 2J(HNi,C′i−1) and 2J(HNi,Cαi) values in 13C/15N‐labeled proteins
Authors: Mukherjee Sulakshana , Mustafi Sourajit M. , Atreya H. S. , Chary K. V. R.
Published: January 2005

Use of partial or selective 13C/15N labeling of specific amino acid residues in a given protein to measure the values of 1J(15Ni,13Cαi), 2J(1HN,13Cαi), 2J(15Ni,13Cαi−1), 1J(15Ni,13C′i−1) and 2J(1HN,13C′i−1) is described. This was achieved by recording a sensitivity‐enhanced 2D [15N–1H] HSQC experiment, without mixing the spin states of Cα and C′ during the course of entire experiment. Copyright © 2005 John Wiley & Sons, Ltd.
NMR spectroscopic analysis of new spiro‐piperidylrifamycins
Authors: Rubio Eduardo , Merino Isabel , García Ana‐Belén , Cabal María‐Paz , Ribas Cristina , Bayod‐Jasanada Miguel
Published: January 2005

New spiro‐piperidylrifamycin derivatives are presented. These compounds were synthesized from the reaction of 3‐amino‐4‐iminorifamycin S and enantiomerically pure 4‐piperidones, which generate diasteroisomeric rifabutin analogues with a new stereocentre at the spiranic carbon. The 1H and 13C NMR spectra of these new compounds, and also the configuration of the new stereogenic centres, were assigned using 2D NMR spectroscopic techniques. A preliminary study of the 1H and 13C NMR spectra of the starting compounds rifamycin S, 3‐amino‐4‐iminorifamycin S and the related rifabutin was also carried out and as a result, their previously published 13C NMR data were corrected. Copyright © 2005 John Wiley & Sons, Ltd.
Total NMR assignments of new [C7OC7″]‐biflavones from leaves of the limonene–carvone chemotype of Lippia alba (Mill) N. E. Brown
Authors: Barbosa Francisco Geraldo , Lima Mary Anne Sousa , Silveira Edilberto Rocha
Published: January 2005

Phytochemical analysis of leaves of the limonene–carvone chemotype of Lippia alba led to the isolation of two biflavonoids with a new structural pattern with an ether linkage: 5,5″‐dihydroxy‐6,4′,6″,3″′,4″′‐pentamethoxy‐[C7OC7″]‐biflavone (1) and 4′,4,5,5″‐tetrahydroxy‐6,6″,3″′‐trimethoxy‐[C7OC7″]‐biflavone (2). Structural elucidation of the new compounds was established on the basis of spectral data, through the use of 1D NMR and several 2D shift correlated NMR pulse sequences (COSY, HMQC, HMBC and NOESY). Copyright © 2005 John Wiley & Sons, Ltd.
Detailed assignments of 1H and 13C NMR spectral data of 13 β‐substituted cycloenones
Authors: Constantino Mauricio Gomes , Júnior Valdemar Lacerda , da Silva Gil Valdo José
Published: January 2005

Detailed assignments of 1H and 13C NMR spectral data for 13 β‐substituted cycloenones are reported. The assignments are based on 1D 1H and 13C NMR and on 2D shift‐correlated (1H,13C‐HMQC and HMBC), J‐resolved and COSY and double irradiation experiments. Copyright © 2005 John Wiley & Sons, Ltd.
Reduction of noise in diffusion tensor images using anisotropic smoothing
Authors: Ding Zhaohua , Gore John C. , Anderson Adam W.
Published: January 2005

To improve the accuracy of tissue structural and architectural characterization with diffusion tensor imaging, a novel smoothing technique is developed for reducing noise in diffusion tensor images. The technique extends the traditional anisotropic diffusion filtering method by allowing isotropic smoothing within homogeneous regions and anisotropic smoothing along structure boundaries. This is particularly useful for smoothing diffusion tensor images in which direction information contained in the tensor needs to be restored following noise corruption and preserved around tissue boundaries. The effectiveness of this technique is quantitatively studied with experiments on simulated and human in vivo diffusion tensor data. Illustrative results demonstrate that the anisotropic smoothing technique developed can significantly reduce the impact of noise on the direction as well as anisotropy measures of the diffusion tensor images. Magn Reson Med 53:485–490, 2005. © 2005 Wiley‐Liss, Inc.
Sizing it up: Cellular MRI using micron‐sized iron oxide particles
Authors: Shapiro Erik M. , Skrtic Stanko , Koretsky Alan P.
Published: January 2005

There is rapidly increasing interest in the use of MRI to track cell migration in intact animals. Currently, cell labeling is usually accomplished by endocytosis of nanometer‐sized, dextran‐coated iron oxide particles. The limitations of using nanometer‐sized particles, however, are that millions of particles are required to achieve sufficient contrast, the label can be diluted beyond observability by cell division, and the label is biodegradable. These problems make it difficult to label cells other than macrophages in vivo, and to conduct long‐term engraftment studies. It was recently demonstrated that micron‐sized iron oxide particles (MPIOs) can be taken up by a number of cell types. In this study we examined the MRI properties of single MPIOs with sizes of 0.96, 1.63, 2.79, 4.50, and 5.80 μm. Furthermore, the capacity of cells to endocytose these MPIOs was investigated, and the MRI properties of the labeled cells at 7.0 and 11.7 Tesla were measured as a function of image resolution and echo time (TE). Cells labeled with MPIOs generally contained iron levels of ∼100 pg, which is approximately threefold higher than those obtained with the best strategies to label cells using nanometer‐sized particles. On occasion, some cells had levels as high as ∼400 pg. We demonstrate that these large particles and the cells labeled with them can be detected by spin echo (SE)‐based imaging methods. These measurements indicate that MPIOs should be useful for improving cell tracking by MRI. Magn Reson Med 53:329–338, 2005. Published 2005 Wiley‐Liss, Inc.
Application of partial differential equation‐based inpainting on sensitivity maps
Authors: Huang Feng , Chen Yunmei , Duensing George R. , Akao James , Rubin Andrew , Saylor Charles
Published: January 2005

Inpainting is an image interpolation method. Partial differential equation (PDE)‐based digital inpainting techniques are finding broad applications. In this paper, PDE‐based inpainting techniques are applied to the field of MR parallel imaging. A novel model and its corresponding numerical method are introduced. This model is then applied to sensitivity maps. Coil sensitivity maps are important for parallel imaging, and they often require extrapolation and hole filling (holes being dark regions of low signal in MR images). These problems can be solved simultaneously by the application of inpainting techniques. Experiments for determining coil sensitivity maps for phantoms and cardiac MR images demonstrate the accuracy of the proposed model. Images generated using sensitivity encoding (SENSE) that utilizes inpainted sensitivity maps, thin‐plate spline (TPS) estimated sensitivity maps, and Gaussian kernel smoothed (GKS) sensitivity maps are compared. From the experimental results, it can be seen that inpainted sensitivity maps produce better results than GKS sensitivity maps. The TPS method generates results similar to those of the inpainting technique but is much more time‐consuming. Magn Reson Med 53:388–397, 2005. © 2005 Wiley‐Liss, Inc.
Interventional magnetic resonance angiography with no strings attached: Wireless active catheter visualization
Authors: Quick Harald H. , Zenge Michael O. , Kuehl Hilmar , Kaiser Gernot , Aker Stephanie , Massing Sandra , Bosk Silke , Ladd Mark E.
Published: January 2005

Active instrument visualization strategies for interventional MR angiography (MRA) require vascular instruments to be equipped with some type of radiofrequency (RF) coil or dipole RF antenna for MR signal detection. Such visualization strategies traditionally necessitate a connection to the scanner with either coaxial cable or laser fibers. In order to eliminate any wire connection, RF resonators that inductively couple their signal to MR surface coils were implemented into catheters to enable wireless active instrument visualization. Instrument background to contrast‐to‐noise ratio was systematically investigated as a function of the excitation flip angle. Signal coupling between the catheter RF coil and surface RF coils was evaluated qualitatively and quantitatively as a function of the catheter position and orientation with regard to the static magnetic field B0 and to the surface coils. In vivo evaluation of the instruments was performed in interventional MRA procedures on five pigs under MR guidance. Cartesian and projection reconstruction TrueFISP imaging enabled simultaneous visualization of the instruments and vascular morphology in real time. The implementation of RF resonators enabled robust visualization of the catheter curvature to the very tip. Additionally, the active visualization strategy does not require any wire connection to the scanner and thus does not hamper the interventionalist during the course of an intervention. Magn Reson Med 53:446–455, 2005. © 2005 Wiley‐Liss, Inc.
The interaction between magnetization transfer and blood‐oxygen‐level‐dependent effects
Authors: Zhou Jinyuan , Payen Jean‐Francois , van Zijl Peter C. M.
Published: January 2005

Low‐power off‐resonance spin‐echo magnetization transfer (MT) imaging experiments with a long repetition time (TR) were performed on rat brain for a range of arterial PCO2 levels. The measured magnetization transfer ratio decreased with increased arterial PCO2 levels. When performing blood‐oxygen‐level‐dependent (BOLD) functional magnetic resonance imaging (fMRI)‐type data analysis in which signal intensities were normalized to the normocapnic state, the CO2‐based BOLD effect was much stronger with than without saturation. This increased effect is a consequence of the fact that the MT effect reduces the signal intensity in tissue more than in blood, thereby amplifying the contribution of the intravascular BOLD signal change to the overall BOLD effect. The results offer a potential approach to measure absolute cerebral blood volume in vivo and to amplify the BOLD effects for fMRI studies. Magn Reson Med 53:356–366, 2005. © 2005 Wiley‐Liss, Inc.
Quantification of airway diameters and 3D airway tree rendering from dynamic hyperpolarized 3He magnetic resonance imaging
Authors: Lewis Tina A. , Tzeng Yang‐Sheng , McKinstry Erin L. , Tooker Angela C. , Hong Kwansoo , Sun Yanping , Mansour Joey , Handler Zachary , Albert Mitchell S.
Published: January 2005

As another step toward extracting quantitative information from hyperpolarized 3He MRI, airway diameters in humans were measured from projection images and multislice images of the lungs. Values obtained were in good agreement with the Weibel lung morphometry model. The measurement of airway caliber can now be achieved without the use of ionizing radiation. Furthermore, it was demonstrated that 3D airway tree renderings could be constructed from the multislice data. Both the measurement of airway diameters and the rendering of 3D airway information hold promise for the clinical assessment of bronchoconstrictive diseases such as asthma and the associated evaluation of treatment effectiveness. Work is being done to address the uncertainties of the manually intensive methods we have developed. Magn Reson Med 53:474–478, 2005. © 2005 Wiley‐Liss, Inc.
Real‐time display of artifact‐free electroencephalography during functional magnetic resonance imaging and magnetic resonance spectroscopy in an animal model of epilepsy
Authors: Mirsattari Seyed M. , Ives John R. , Bihari Frank , Leung L. Stan , Menon Ravi S. , Bartha Robert
Published: January 2005

Simultaneous recording of electroencephalogram (EEG) and functional MRI (fMRI) or MR spectroscopy (MRS) can provide further insight into our understanding of the underlying mechanisms of neurologic disorders. Current technology for simultaneous EEG and MRI recording is limited by extensive postacquisition processing of the data. Real‐time display of artifact‐free EEG recording during fMRI/MRS studies is essential in studies that involve epilepsy to ensure that they address specific EEG features such as epileptic spikes or seizures. By optimizing the EEG recording equipment to maximize the common mode rejection ratio of its amplifiers, a unique EEG system was designed and tested that allowed real‐time display of the artifact‐free EEG during fMRI/MRS in an animal model of epilepsy. Spike recordings were optimized by suppression of the background EEG activity using fast‐acting and easily controlled inhalational anesthesia. Artifact suppression efficiency of 70–100% was achieved following direct subtraction of referentially recorded filtered EEG tracings from active electrodes, which were located in close proximity to each other (over homologous occipital cortices) and a reference electrode. Two independent postacquisition processing tools, independent component analysis and direct subtraction of unfiltered digital EEG data in MATLAB, were used to verify the accuracy of real‐time EEG display. Magn Reson Med 53:456–464, 2005. © 2005 Wiley‐Liss, Inc.
Chemical‐shift‐selective filter for the in vivo detection of J‐coupled metabolites at 3T
Authors: Schulte Rolf F. , Trabesinger Andreas H. , Boesiger Peter
Published: January 2005

A chemical‐shift‐selective filter (CSSF) was applied to the detection of J‐coupled metabolites in the human brain. This filter is an acquisition‐based technique that requires the chemical shifts (CS's) of different metabolites, but not their whole multiplet structures, to be resolved. The sequence is based on the 2D constant‐time spin‐echo experiment, which yields pure CS spectra in the indirect dimension. Localization is achieved through point‐resolved spectroscopy (PRESS). The method enables unequivocal detection of glutamate and myo‐inositol, both in vitro and in vivo in the human brain, at 3T. Magn Reson Med 53:275–281, 2005. © 2005 Wiley‐Liss, Inc.
Quantitative breath‐hold monitoring of myocardial gadolinium enhancement using inversion recovery TrueFISP
Authors: Goldfarb James W. , Mathew Sunil T. , Reichek Nathaniel
Published: January 2005

The purpose of this work was to develop and evaluate the accuracy of a breath‐hold IR‐TrueFISP acquisition capable of monitoring gadolinium (Gd) concentrations through T1 measurements in the left ventricular blood pool and segments of the myocardium over an extended duration. Measurements using a phantom were performed to assess the accuracy of the technique. Accurate T1 measurements in the expected range after contrast agent administration were obtained with several theoretical formulations. Accurate T1 values before the administration of the contrast agent were obtained only when the incomplete recovery of magnetization during the delay time (TD) between imaging segments was incorporated into the observed signal intensity calculations. T1 measurements over a 1‐hr time period were performed in four subjects with known myocardial infarctions. In this small study, Gd differences between recent and old myocardial infarctions were observed. Magn Reson Med 53:367–371, 2005. © 2005 Wiley‐Liss, Inc.
Tozer et al. Quantitative Magnetization Transfer Mapping of Bound Protons in Multiple Sclerosis, Magn Reson Med 2003;50:83‐91
Authors: Tofts P.S. , Cercignani M. , Tozer D.J. , Symms M.R. , Davies G.R. , Ramani A. , Barker G.J.
Published: January 2005

The original article to which this Erratum refers was published in Magnetic Resonance in Medicine (2003) 50(1) 83–91.
Reduction of blurring in view angle tilting MRI
Authors: Butts Kim , Pauly John M. , Gold Garry E.
Published: January 2005

Magnetic resonance imaging (MRI) in the presence of metallic objects suffers from slice‐selection errors and in‐plane distortions. View angle tilting (VAT) corrects for in‐plane distortions by adding a gradient on the slice‐select axis during readout, but can suffer from image blurring. This work demonstrates that the major source of blurring is a slice profile modulation of the data, and proposes several solutions to prevent such blurring. Multiple high‐bandwidth readouts are demonstrated to reduce the blurring while improving the signal‐to‐noise ratio (SNR) over a single high‐bandwidth readout. Magn Reson Med 53:418–424, 2005. © 2005 Wiley‐Liss, Inc.
Age‐related decline in muscle strength and power output in acid 1–4 α‐glucosidase knockout mice
Authors: Hesselink Reinout P. , Van Kranenburg Gerrit , Wagenmakers Anton J. M. , Van der Vusse Ger J. , Drost Maarten R.
Published: January 2005

A hallmark of glycogen storage disease type II, caused by defective α‐glucosidase (AGLU) activity, is a progressive decline in muscle performance. The objective of this study was to determine the relative contribution to this decline in muscle performance of (1) decline in muscle mass; (2) decline in muscle protein content per unit mass; and (3) accumulation of glycogen. To this end, isometric torque and power in AGLU−/− mice at 7, 13, and 20 months were assessed in situ. Power (∼24 mW) and torque (∼2.45 Nmm) did not change with age in control animals, but declined significantly in AGLU−/− mice, in the three age groups. No decline in protein content per unit muscle mass was observed. Muscle atrophy explained one third of the decline in muscle performance; the remaining part was attributed to a decrease in muscle quality—a decrease in mechanical performance per unit muscle mass. Mechanical effects of glycogen inclusions could not fully explain this decrease. Additional factors must therefore play a role. Muscle Nerve, 2005
Co‐morbidity of ‘Clinical Trial’ versus ‘Real‐World’ patients using cardiovascular drugs
Authors: Wieringa Nicolien F. , Vos Rein , Van Der Werf Ger Th. , Van Der Veen Willem Jan , De Graeff Pieter A.
Published: January 2005

Purpose

To examine discrepancies between co‐morbidity of patients included in pre‐marketing clinical trials of cardiovascular drugs and patients from daily practice, representing the actual users after marketing, and to investigate the availability of data regarding co‐morbidity in registration files.

Methods

Data were collected from phase III trials of registration files of 16 drugs, registered in the Netherlands in the period 1985 through 1994 for the indications hypertension, angina pectoris or hypercholesterolemia, and from a general practitioners database. Patients were selected who used drugs from the same therapeutic classes for the same indication as the patients in the pre‐marketing trials. Prevalences of concomitant cardiovascular, endocrine and metabolic diseases were compared between pre‐ and postmarketing populations. Discrepancies were defined as more than 10% difference in prevalences.

Results

Data regarding co‐morbidity were present in 13 out of 16 registration files and differed in format of reporting. For all indications, coexisting cardiovascular, endocrine and metabolic diseases were less prevalent in the pre‐marketing populations, except ischemic heart disease, which was more prevalent coexisting with angina pectoris and hypercholesterolemia. Discrepancies were found for hypertensive disease, heart failure, diabetes mellitus and myocardial infarction.

Conclusions

Phase III trials testing cardiovascular drugs included patients with concomitant cardiovascular, endocrine and metabolic diseases, but discrepancies were present with patients in daily practice. Development of guidelines for uniform collection and reporting of co‐morbidity data in pre‐marketing trials is recommended, as well as further utilization of data. Copyright © 2000 John Wiley & Sons, Ltd.
Do NHLBI lung function criteria apply to children? A cross‐sectional evaluation of childhood asthma at National Jewish Medical and Research Center, 1999–2002
Authors: Paull Keith , Covar Ronina , Jain Neal , Gelfand Erwin W. , Spahn Joseph D.
Published: January 2005

Although National Heart Lung Institute (NHLBI) guidelines categorize asthma severity based on spirometry, few studies have evaluated the utility of these spirometric values in grading asthma severity in children. Asthma is thought to be progressive, but little is known about the loss of lung function in childhood. This study sought to determine the spirometric indices in children from 4–18 years of age. Retrospective cross‐sectional analysis was performed on all spirometries done in children at the National Jewish Medical and Research Center from 1999–2002. In total, 2,728 children performed 24,388 measures. The mean ± SD values for forced vital capacity (FVC), forced expired volume in 1 sec (FEV1), FEV1/FVC ratio, and forced expiratory flow (FEF)25–75 were 92.7 ± 16.2, 92.2 ± 18.0, 85.3 ± 9.3, and 78.0 ± 36.5 percent predicted, respectively. Seventy‐seven percent of FEV1 values were ≥ 80%, 18.6% were between 60–80%, and 3.1% were <60% of predicted. FEV1 was highest in 5‐year‐old children; it declined thereafter, reaching a nadir at 11 years, followed by a partial recovery from 12–18 years. Expressed in liters, FEV1 values were lower than expected at every age, with the greatest difference at 18 years. FEV1/FVC ratios declined through childhood, suggesting impaired airway but not lung growth in children with asthma. In conclusion, the majority of asthmatic children attending a tertiary care facility had FEV1 values within normal range. With increasing age, the increase in FEV1 lags behind that of nonasthmatics, so that by 18 years, maximum FEV1 is impaired. The NHLBI FEV1 cutoff values do not appear to accurately stratify pediatric asthma, and no useful FEV1 cutoff could be generated. Pediatr Pulmonol. 2005; 39:311–317. © 2005 Wiley‐Liss, Inc.
Misdiagnosing cystic fibrosis in the era of gene analysis: Case reports
Authors: Moser Chuanpit , Nussbaum Eliezer , Thompson Rohan
Published: January 2005

We present a scenario of how gene analysis plays a confusing role in the diagnosis of cystic fibrosis (CF). One of the two siblings we are presenting here was initially misdiagnosed as having CF, based on the two CF gene mutations identified by gene analysis. A CF gene study on the other sibling years later, however, led to further investigation and eventually to a change of diagnosis. As interesting and important as gene analysis is in CF, one must always look at each patient in the big picture. Included in the picture, in addition to the state‐of‐the‐art genotype, is the phenotype, or (to simplify) the back‐to‐basic clinical manifestations. Pediatr Pulmonol. 2005; 39:379–381. © 2005 Wiley‐Liss, Inc.
Negative thermal expansion in the layered semiconductor TlGaSe2
Authors: Abdullayev N. A. , Mammadov T. G. , Suleymanov R. A.
Published: January 2005

The nature of negative thermal expansion in the layer plane of the layered semiconductor TlGaSe2 has been investigated. It is shown that, in contrast to other crystals with a layered structure in which negative linear expansion is observed, the nature of the negative thermal expansion in TlGaSe2 crystals is due to the large Poisson contraction. The possible explanation of such an effect is discussed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Shot noise and higher current moments in dimensions 2, 3 and 4
Authors: Travěnec I.
Published: January 2005

Shot noise and higher current moments TM = 〈Tr (t†t)M〉 are studied within the Anderson model of disordered conductors in dimensions d = 2, 3 and 4. Here t denotes a transmission matrix. We calculate the conductance G = T1, shot noise S = T1–T2, Fano factor F = S/G and ratios CM = TM /G, and we show indications that all of them are as good order parameters as the conductance itself. In the limit of infinite system size, two limiting values of and CM are found; the stable one in the metallic regime, and the unstable one, characterizing the critical point for d > 2. We present analytical expressions for both limiting values, together with a compact formula for current cumulants at 3D criticality. Our data confirm also Nazarov's microscopic theory [Phys. Rev. B 52, 4720 (1995)], as we show numerically for special linear combinations of TM. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Polaron effects due to interface optical‐phonons in wurtzite GaN/AlN quantum wells
Authors: Zhu Yao‐hui , Shi Jun‐jie
Published: January 2005

Considering the effects of the built‐in electric field (BEF) induced by the spontaneous and piezoelectric polarizations of wurtzite GaN/AlN quantum wells (QW's), the polaron energy shift and the effective mass due to the electron interactions with the interface optical‐phonons are investigated theoretically by means of Lee‐Low‐Pines variational approach. We find that the BEF has a remarkable influence on the polaron effects especially for a QW with well widthd> 6 nm. The polaron energy shift increases slowly and its effective mass approaches to a constant ifdis further increased. On the contrary, both the polaron energy shift and the effective mass decrease slowly with the increasing ofdif the BEF is ignored. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Polarization behavior in systems with competing ferroelectric and antiferroelectric interactions
Authors: Milhazes J. , Lanceros‐Méndez S. , Cadilhe A.
Published: January 2005

The dielectric hysteresis loop constitutes the main feature indicative of the properties of a ferroelectric material, but in complex systems with ferro‐ and antiferroelectric interactions, the hysteresis loops are often multiple. In the present work, we introduce a model based on the coexistence of ferro‐ and antiferroelectric regions, which can describe the aforementioned multiple loops. Based on our model, simulated multiple hysteresis loops are in good agreement with experimental results. Hysteresis loops obtained from our model are sensitive to the relative values of the ferro‐ and antiferroelectric coupling constants, domain size, and temperature. The model describes well systems without the presence of frustration as it is the case of BAxBP1–x. In the case of systems exhibiting frustration like e.g. Rbx(NH4)1–xH2PO4, we present a straightforward extension of our model. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Compton profile study of thulium
Authors: Malhotra H. , Heda N. L. , Ahuja B. L.
Published: January 2005

First high‐precision measurement of the isotropic Compton spectra of thulium has been carried out, at an intermediate resolution of 0.40 a.u., using 137Cs as a γ‐ray source. For the interpretation of data, theoretical calculations were undertaken using renormalised‐free‐atom (RFA) and free electron models. It is seen that the RFA calculation with e––e– correlation gives a better agreement with the experiment. From our experimental and theoretical Compton profile data, we have also computed for the first time the cohesive energy of thulium and compared it with available data. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mössbauer scattering by superparamagnetic particles
Authors: Dzyublik A. Ya.
Published: January 2005

A theory of Mössbauer scattering by superparamagnetic particles with stochastically reversing magnetization is presented, where the mean time between reversals greatly exceeds the nuclear lifetime. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thomas–Fermi–Dirac calculations of valence band states in two p‐type delta‐doped ZnSe quantum wells
Authors: Rodriguez‐Vargas I. , Gaggero‐Sager L. M. , Martinez‐Orozco J. C.
Published: January 2005

We present the hole sub‐band structure study in two p‐type δ‐doped ZnSe QW's. An analytical expression for the Hartree–Fock potential is obtained following the lines of the Thomas–Fermi–Dirac (TFD) approximation. We have analyzed the dependence of the hole energy levels to the impurity density and the interlayer distance between wells. The exchange effects are also included in the present survey. We find that many body effects cannot be ignored because these are really important in the calculation at least in the low concentration regime. We have obtained an energy difference between the top of the valence band and the ground energy of the heavy hole ladder of meV in good agreement with the experimental reports ( eV) available. We calculate the mobility ratio between double δ‐doped QW's and simple δ‐doped QW based on a phenomenological formula. We find the optimum interlayer distance between wells for maximum mobility for three impurity concentrations, which can be of great importance for technological applications. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetic properties of the nonstoichiometric Sr‐doped manganites
Authors: Trukhanov S. V. , Troyanchuk I. O. , Fedotova V. V. , Ryzhov V. A. , Maignan A. , Flahaut D. , Szymczak H. , Szymczak R.
Published: January 2005

The chemical phase content, crystal structure, and magnetization for the doped anion‐deficient La1–xSrxMnO3–x/2 (x = 0, 0.05, 0.10, 0.20, 0.30) manganites have been studied. The samples undergo the structural phase transition from the O′‐orthorhombic to the rhombohedric unit cell at x > 0.10. As doping level and oxygen deficiency increase the samples show a number of magnetic transitions. In the region of 0.05 ≤ x ≤ 0.20 the samples are inhomogeneous ferromagnets while at x = 0.30 they are cluster spin glasses. The temperature of the magnetic moment freezing is ∼45 K. The concentration dependences of the spontaneous magnetization and coercivity as well as magnetic phase diagram have been constructed. The magnetic properties of the anion‐deficient Sr‐doped samples may be interpreted on the basis of competition of the positive Mn3+(6)–O–Mn3+(6) and negative Mn3+(5)–O–Mn3+(6) isotropic superexchange interactions and impurity phase separation models. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An Application of Six Sigma to Reduce Waste
Authors: Bañuelas Ricardo , Antony Jiju , Brace Martin
Published: January 2005

Six Sigma has been considered a powerful business strategy that employs a well‐structured continuous improvement methodology to reduce process variability and drive out waste within the business processes using effective application of statistical tools and techniques. Although there is a wider acceptance of Six Sigma in many organizations today, there appears to be virtually no in‐depth case study of Six Sigma in the existing literature. This involves how the Six Sigma methodology has been used, how Six Sigma tools and techniques have been applied and how the benefits have been generated. This paper presents a case study illustrating the effective use of Six Sigma to reduce waste in a coating process. It describes in detail how the project was selected and how the Six Sigma methodology was applied. It also shows how various tools and techniques within the Six Sigma methodology have been employed to achieve substantial financial benefits. Copyright © 2005 John Wiley & Sons, Ltd.
Structural assignment of isomeric 2‐aminopyridine‐derivatized oligosaccharides using MSn spectral matching Yasuhiro Takegawa, Shinya Ito, Shinji Yoshioka, Kisaburo Deguchi, Hiroaki Nakagawa, Kenji Monde and Shin‐Ichiro Nishimura Rapid Commun. Mass Spectrom. 2004; 18: 385–391
Authors: Takegawa Yasuhiro , Ito Shinya , Yoshioka Shinji , Deguchi Kisaburo , Nakagawa Hiroaki , Monde Kenji , Nishimura Shin‐Ichiro
Published: January 2005

The original article to which this Erratum refers was published in Rapid Commun. Mass Spectrom. 2004; 18: 385–391
Investigations of cluster ions formed between cesium cations and benzoic, salicylic and phthalic acids by electrospray mass spectrometry and density‐functional theory calculations. Toward a modeling of the interaction of Cs+ with humic substances
Authors: Maria Pierre‐Charles , Gal Jean‐François , Massi Lionel , Burk Peeter , Tammiku‐Taul Jaana , Tamp Sven
Published: January 2005

A concerted theoretical (density‐functional theory) and experimental electrospray mass spectrometry study was conducted on the formation of cesium cation adducts with small molecules taken as models of specific interactions sites in humic substances. Electrospray experiments with phenol, benzoic acid, salicylic acid, and phthalic acid, in methanolic solution containing cesium nitrate, were performed using a quadrupole ion trap. The formation of positively charged mixed clusters, [Cs(CsNO3)n(CsA1)m(Cs2A2)p]+ (A1 = benzoate, salicylate, and hydrogenophthalate, A2 = phthalate), was observed. Calculations of structures and bonding energetics of Cs+ in simple adducts formed with NO, CsNO3, A−, AH, and CsA are reported. The observation of variable cluster stoichiometry (n, m and p values) was interpreted in terms of more or less favorable interaction energies between Cs+ and the neutral species constituting the clusters. Phenol did not form clusters in significant abundances, despite a strong calculated interaction between Cs+ and cesium phenolate. This was attributed to its weak acid dissociation in the electrospray solution. Copyright © 2005 John Wiley & Sons, Ltd.
Development of a liquid chromatography/electrospray tandem mass spectrometry method for confirmation of chloramphenicol residues in milk after alfa‐1‐acid glycoprotein affinity chromatography
Authors: Gallo Pasquale , Nasi Antonella , Vinci Floriana , Guadagnuolo Grazia , Brambilla Gianfranco , Fiori Maurizio , Serpe Luigi
Published: January 2005

In this work we present a method for confirmatory analysis of chloramphenicol (CAP) in bovine and buffalo raw milk. CAP is extracted in acetonitrile and purified by affinity chromatography on an α‐1‐acid glycoprotein (AAG) column, then is identified and determined by ion‐trap liquid chromatography/electrospray ionisation tandem mass spectrometry (LC/ESI‐MS/MS) analysis in the negative ion mode. CAP was identified at the minimum required performance limit (MRPL) of 0.30 ppb, by monitoring the [M–H]− ion and at least two product ions, meeting the qualitative and quantitative criteria set by the European Commission in Decision 2002/657/EC for confirmation of prohibited veterinary drugs. The trueness and within‐day and between‐day repeatability data are also reported. Moreover, the loading capacity of affinity columns towards CAP was tested. This method, based on the molecular recognition between drug and AAG during the purification step to improve sample cleanup, represents a quantitative and repeatable procedure for confirmatory analysis, and fits the requirements for the routine official control of CAP residues in raw milk. Copyright © 2005 John Wiley & Sons, Ltd.
Not only the tragedy of the commons: misperceptions of feedback and policies for sustainable development
Authors: Moxnes Erling
Published: January 2005

The article summarizes key insights from four laboratory experiments to study renewable resource management. The commons problem, which is widely held to be the cause of mismanagement of common renewable resources, was ruled out by the design of the experiments. Still the participants overinvested and overutilized their resources. The explanation offered is systematic misperceptions of stocks and flows and of nonlinearities. The heuristics that people apply are intendedly rational for static, flow resources, but not for dynamic, stock resources. Simplifying and reframing the management problem, by focusing on net growth rates, is suggested as a means to foster the use of more appropriate heuristics. Copyright © 2000 John Wiley & Sons, Ltd.
Analysis of 1H NMR‐detectable mobile lipid domains for assessment of apoptosis induced by inhibitors of DNA synthesis and replication
Authors: Mikhailenko V.M. , Philchenkov A.A. , Zavelevich M.P.
Published: January 2005

Cell membrane rearrangements coincident with apoptosis may contribute to the increase in the ratio of methylene (CH2 at 1.3 ppm) to methyl (CH3 at 0.9 ppm) resonance signal intensity as observed by proton nuclear magnetic resonance (1H NMR).

We studied CH2 and CH3 resonances in cultured cell lines treated with etoposide and fludarabine or bioflavonoid quercetin. Etoposide treatment (10 μM, 18 h) resulted in 3.3 fold increase of the CH2/CH3 signal intensity ratio and 6.4 fold decrease in choline signal of MT4 cells. Incubation of Namalwa cells with fludarabine (3 μM, 72 h) increased the CH2/CH3 signal intensity ratio by 2.4 fold and choline resonance intensity was unchanged. Quercetin treatment (30 μM, 1.5 month) increased CH2/CH3 ratio by 2.1 fold. Necrotic cell death upon ethanol (20%) or DMSO (30%) treatment did not change the CH2/CH3 signal intensity ratio. 1H NMR‐based study of mobile lipid domains is sensitive for detection of early engagement into apoptosis.
A novel alkali‐tolerant Yarrowia lipolytica strain for dissecting Na+‐coupled phosphate transport systems in yeasts
Authors: Zvyagilskaya Renata , Persson Bengt L.
Published: January 2005

The newly isolated osmo‐, salt‐ and alkali‐tolerant Yarrowia lipolytica yeast strain is remarkable by its capacity to grow at alkaline pH values (pH 9.7), which makes it an excellent model system for studying Na+‐coupled phosphate transport systems in yeast cells grown at alkaline conditions. In cells Y. lipolytica grown at pH 9.7, phosphate uptake was mediated by several kinetically discrete Na+‐dependent systems that are specifically activated by Na+ ions. One of these, a low‐affinity transporter, operated at high‐phosphate concentrations. The other two, derepressible, high‐affinity, high‐capacity systems, functioned during phosphate starvation. Both H+‐ and Na+‐coupled high‐affinity phosphate transport systems of Y. lipolytica cells were under the dual control of the prevailing extracellular phosphate concentrations and pH values. The contribution of the Na+/Pi‐cotransport systems into the total cellular phosphate uptake activity was progressively increased with increasing pH, reaching its maximum at pH ≥ 9.
Do tagging experiments tell the truth? Using electronic tags to evaluate conventional tagging data
Authors: Bolle Loes J. , Hunter Ewan , Rijnsdorp Adriaan D. , Pastoors Martin A. , Metcalfe Julian D. , Reynolds John D.
Published: January 2005

For more than a century, scientists have used mark-recapture techniques to describe the spatial dynamics of marine demersal fish species in the North Sea. Although such experiments have provided extensive data sets, the information is limited to the date and position at release and at recapture. Furthermore, these data may be biased due to the distribution of fishing effort. Recently, electronic (archival) data storage tags (DSTs) have successfully been used to reconstruct the movements of free-ranging demersal fish between release and recapture. Data from DST experiments allow the calculation of fisheries-independent migration parameters, and thereby provide a means of evaluating conventional tagging data. We compared the migration patterns of North Sea plaice (Pleuronectes platessa L.) as inferred from a database of twentieth century conventional tagging experiments (CT), with data from 132 plaice tagged with DST. In general, the CT experiments allowed a reliable interpretation of migration patterns, although for certain release areas the migration distances were biased due to the heterogeneous distribution of fishing effort.