bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure, form, and function of flight in engineering and the living world
Authors: Lindhe Norberg Ulla M.
Published: August 2002

By combining appearance and behavior in animals with physical laws, we can get an understanding of the adaptation and evolution of various structures and forms. Comparisons can be made between animal bodies and various technical constructions. Technical science and theory during the latest decades have resulted in considerable insight into biological adaptations, but studies on structures, forms, organs, systems, and processes in the living world, used in the right way, have also aided the engineer in finding wider and better solutions to various problems, among them in the design of micro‐air vehicles (MAVs). In this review, I discuss the basis for flight and give some examples of where flight engineering and nature have evolved similar solutions. In most cases technology has produced more advanced structures, but sometimes animals are superior. I include how different animals have solved the problem of producing lift, how animal wings meet the requirements of strength and rigidity, how wing forms are adapted to various flight modes, and how flight kinematics are related to flight behavior and speed. The dynamics of vorticity is summarized. There are a variety of methods for the determination of flight power; it has been estimated adequately by lifting‐line theory, by physiological measurements, and from mass loss and food intake. In recent years alternative methods have been used, in which the mechanical power for flight is estimated from flight muscle force used during the downstroke. Refinements of these methods may create new ways of estimating flight power more accurately. MAVs operate at the same Reynolds numbers as large insects and small birds and bats. Therefore, studies on animal flight are valuable for MAV design, which is discussed here. J. Morphol. 252:52–81, 2002. © 2002 Wiley‐Liss, Inc.
Direct monitoring of molecular recognition processes using fluorescence enhancement at colloid‐coated microplates
Authors: Lobmaier Ch. , Hawa G. , Götzinger M. , Wirth M. , Pittner F. , Gabor F.
Published: August 2002

Direct monitoring of recognition processes at the molecular level is a valuable tool for studying reaction kinetics to assess affinity constants (e.g. drugs to receptors) and for designing rapid single step immunoassays. Methods currently used to gain information about binding processes predominantly depend on surface plasmon resonance. These systems use excitation with coherent light in attenuated total reflection geometry to obtain discrimination between surface‐bound and free molecules in solution. Therefore labeling of the compounds is not necessary, but due to the complexity of the measuring setup the method is rather costly. In this contribution we present a simple method for performing kinetic single step biorecognition assays with fluorophore labeled compounds using the fluorescence enhancement properties of surface bound silver colloids. Silver colloids are bound to standard microplates via silanization of the plastic surface. Fluorophores close to this colloid coated surface show a significant gain in fluorescence compared to fluorophores farther away in the bulk solution. Therefore discrimination between surface bound and free fluorophores is possible and the binding of, for example, fluorophore labeled antibodies to antigens immobilized on the colloid surface results in increasing fluorescence intensity. Utilization of standard microplates makes this method fully compatible with conventional microplate processing and reading devices. Neither excitation with coherent laser light nor ATR geometry is required, the measurement is performed in a standard fluorescence microplate reader in front face geometry with a xenon flash lamp as excitation source. Methods for the preparation of colloid‐coated microplates and fluorescence‐enhanced biorecognition assays are presented. Additionally the dependence of the system performance on the structure and properties of the metal colloid coated surface is described. A two‐component biorecognition model system shows a detection limit in the subnanomolar range. The ease of colloid‐surface preparation and the high sensitivity makes fluorescence enhancement at colloid‐coated microplates a valuable tool for studying reaction kinetics and performing rapid single‐step immunoassays. Copyright © 2001 John Wiley & Sons, Ltd.
Oxytocin‐induced phosphorylation of myosin light chain is mediated by extracellular calcium influx in pregnant rat myometrium
Authors: Shojo Hideki , Kaneko Yuji
Published: August 2002

Studies of oxytocin‐induced phosphorylation of myosin light chain (MLC), resulting in myometrial contraction, suggest that extracellular Ca2+ influx is involved in its signal transduction. To explore the possibility that intracellular Ca2+ mobilization by oxytocin may also contribute to MLC phosphorylation, we investigated the relative contributions of these Ca2+ sources to oxytocin signal transduction in myometrium of pregnant rat. In pregnant rat myometrium, oxytocin‐induced Ca2+ influx occurs via an L‐type voltage‐dependent Ca2+ channel. Treatment with verapamil, an antagonist specific for these channels, significantly diminished MLC phosphorylation observed in response to oxytocin administration without affecting the release of Ca2+ from intracellular Ca2+ stores. Furthermore, oxytocin‐induced MLC phosphorylation was not observed when extracellular Ca2+ was not present. Our results clearly indicate that extracellular Ca2+ influx, rather than release from Ca2+ storage sites, is essential for oxytocin‐induced MLC phosphorylation. Copyright © 2001 John Wiley & Sons, Ltd.
Mycotic aortocaval fistula: Efficient evaluation by bolus‐chase MR angiography
Authors: Torigian Drew A. , Carpenter Jeffrey P. , Roberts David A.
Published: August 2002

Aortocaval fistula (ACF) is a rare but life‐threatening condition. This case report describes the use of bolus‐chase gadolinium‐enhanced 3D magnetic resonance angiography (MRA) to provide an efficient evaluation of a patient with ACF associated with a mycotic abdominal aortic aneurysm. This case highlights the ability of bolus‐chase MRA to provide both the specific diagnosis of ACF as well as the information necessary for extra‐anatomic arterial bypass. Bolus‐chase MRA is a promising method for the evaluation of patients with this disease entity. J. Magn. Reson. Imaging 2002;15:195–198. © 2002 Wiley‐Liss, Inc.
In vivo diffusion tensor imaging of human calf muscle
Authors: Sinha Usha , Yao Lawrence
Published: August 2002

Purpose

To investigate a tetrahedral diffusion gradient encoding scheme to measure the diffusion tensor in vivo for human calf muscle.

Materials and Methods

The theoretical TE which maximizes the signal‐to‐noise ratio (SNR) of the diffusion images was derived for both the orthogonal and tetrahedral sampling strategies and the SNR advantage verified experimentally. A diffusion echo‐planar imaging (EPI) sequence was used to image five volunteers. Gradient cycling and geometric averaging was performed to eliminate cross‐terms between the imaging and diffusion gradients.

Results

Trace diffusion coefficients in human muscle are spatially invariant and have low intersubject variability (<4%). Images of the off‐diagonal terms confirm the anisotropy of muscle, and fiber orientation maps were derived from these off‐diagonal images. A noninvariant index of anisotropy, Aratio (average value: 1.28), was found to be less susceptible to noise than the invariant index.

Conclusion

This technique is robust and can be readily implemented on clinical scanners with EPI capabilities. J. Magn. Reson. Imaging 2002;15:87–95. © 2002 Wiley‐Liss, Inc.
Fast phase contrast cardiac magnetic resonance imaging: Improved assessment and analysis of left ventricular wall motion
Authors: Markl Michael , Schneider Britta , Hennig Jürgen
Published: August 2002

Purpose

To evaluate the use of CINE phase contrast magnetic resonance imaging (MRI) to assess and characterize left ventricular wall motion by two‐ or three‐directional velocity vector fields that reflect the temporal evolution of myocardial velocities over the whole cardiac cycle.

Material and Methods

A fast imaging protocol is presented that permits the assessment of the pixel‐wise full in‐plane velocity information of the beating heart within a single breath‐hold measurement. Temporal resolution of the acquired images is improved by the use of high‐speed gradients and application of view sharing to black blood k‐space segmented gradient echo imaging. A novel tool for data analysis is presented based on correlating locally different myocardial motion patterns to averaged left ventricular velocities reflecting nonpathological myocardial function.

Results

Measurement protocol and postprocessing options were evaluated in a study with 16 normal volunteers. Simulations showed that correlation analysis can be used to differentiate regions with altered velocity waveforms from global radial velocities. Results of patient examinations are presented on an exemplary basis and demonstrate that correlation analysis provides an effective method for identification and classification of myocardial dynamics.

Conclusion

Within the framework of our volunteer and patient examinations, fast phase contrast cardiac MRI has proven to be a reliable method to assess and analyze myocardial performance on the basis of two‐directional velocity vector fields. J. Magn. Reson. Imaging 2002;15:642–653. © 2002 Wiley‐Liss, Inc.
Real‐time MRI of joint movement with trueFISP
Authors: Quick Harald H. , Ladd Mark E. , Hoevel Matthias , Bosk Silke , Debatin Joerg F. , Laub Gerhard , Schroeder Tobias
Published: August 2002

Purpose

To develop a technique for dynamic magnetic resonance imaging (MRI) of joint motion based on a combination of real‐time TrueFISP (fast imaging with steady state precession) imaging with surface radiofrequency (RF) coils.

Materials and Methods

The metacarpal, elbow, tarsal, and knee joint of five volunteers and the knees of four patients were examined with a real‐time TrueFISP sequence during movement of the joints.

Results

All examined joints could be assessed under dynamic conditions with high image contrast and high temporal resolution.

Conclusion

Dynamic MRI of joints with TrueFISP is feasible and can provide information supplemental to static joint examinations. J. Magn. Reson. Imaging 2002;15:710–715. © 2002 Wiley‐Liss, Inc.
Prediction of postoperative pulmonary function using perfusion magnetic resonance imaging of the lung
Authors: Iwasawa Tae , Saito Kimihiko , Ogawa Nobuo , Ishiwa Naoki , Kurihara Hiroaki
Published: August 2002

Purpose

To assess semiquantitatively the regional distribution of lung perfusion using magnetic resonance (MR) perfusion imaging.

Materials and Methods

Subjects were 20 consecutive patients with bronchogenic carcinoma, who underwent MR imaging (MRI) and radionuclide (RN) perfusion scans for preoperative evaluation. Three‐dimensional (3D) images of whole lungs were obtained before and 7 seconds after bolus injection of contrast material (5 ml of Gd‐DTPA). Subtraction images were constructed from these dynamic images. Lung areas enhanced with the contrast material were measured and multiplied by changes in signal intensity, summed for the whole lung, and the right‐to‐left lung ratios were calculated. The predicted postoperative forced expiratory volume in 1 second (FEV1) was estimated using MR and RN perfusion ratios.

Results

The correlation between perfusion ratios derived from the MR and RN studies was excellent (r = 0.92). Sixteen of 20 patients underwent surgery, and 12 patients had postoperative pulmonary function tests. The predicted FEV1 derived from the MR perfusion ratio correlated well with the postoperative FEV1 in the 12 patients (r = 0.68).

Conclusion

Perfusion MRI is suitable for semiquantitative evaluation of regional pulmonary perfusion. J. Magn. Reson. Imaging 2002;15:685–692. © 2002 Wiley‐Liss, Inc.
Hyperpolarized 3He MR lung ventilation imaging in asthmatics: Preliminary findings
Authors: Altes Talissa A. , Powers Patrick L. , Knight‐Scott Jack , Rakes Gary , Platts‐Mills Thomas A.E. , de Lange Eduard E. , Alford Bennett A. , Mugler John P. , Brookeman James R.
Published: August 2002

Asthma is a disease characterized by chronic inflammation and reversible obstruction of the small airways resulting in impaired pulmonary ventilation. Hyperpolarized 3He magnetic resonance (MR) lung imaging is a new technology that provides a detailed image of lung ventilation. Hyperpolarized 3He lung imaging was performed in 10 asthmatics and 10 healthy subjects. Seven asthmatics had ventilation defects distributed throughout the lungs compared with none of the normal subjects. These ventilation defects were more numerous and larger in the two symptomatic asthmatics who had abnormal spirometry. Ventilation defects studied over time demonstrated no change in appearance over 30–60 minutes. One asthmatic subject was studied twice in a three‐week period and had ventilation defects which resolved and appeared in that time. This same subject was studied before and after bronchodilator therapy, and all ventilation defects resolved after therapy. Hyperpolarized 3He lung imaging can detect the small, reversible ventilation defects that characterize asthma. The ability to visualize lung ventilation offers a direct method of assessing asthmatics and their response to therapy. J. Magn. Reson. Imaging 2001;13:378–384. © 2001 Wiley‐Liss, Inc.
Ultrasmall particulate iron oxides as contrast agents for magnetic resonance spectroscopy: A dose‐effect study
Authors: Le Duc Géraldine , Vander Elst Luce , Colet Jean Marie , Roch Alain , Gillis Pierre , Le Bas Jean François , Muller Robert N.
Published: August 2002

Long‐distance effects of a superparamagnetic contrast agent (AMI227) were investigated by phosphorus‐31 NMR spectroscopy at 7.05 Tesla. In an initial methodological approach, the effects observed on phantoms were compared to the results of theoretical calculations. In a second step, the particles were administered to excised and perfused rat livers (N = 5) and hearts (N = 5) through the perfusion medium for 12 minutes at various concentrations (0.9, 1.8, and 3.6 mM Fe). Organs were subsequently rinsed with the perfusion medium for 42 minutes. During particle perfusion, the spectral lines were shifted and exhibited a strong broadening, although the peak area remained constant, testifying to the inocuity of the material. For hearts only, these disturbances disappeared upon organ rinsing. These through‐space susceptibility effects of the particles located in the vessels on phosphorus nuclei, which are strictly confined to the intracellular space, show that high‐susceptibility intravascular agents could be useful to evaluate tissue perfusion by contrast‐enhanced spectroscopy. J. Magn. Reson. Imaging 2001;13:619–626. © 2001 Wiley‐Liss, Inc.
Necropsy by magnetic resonance in a case of conjoined thoracopagus twins
Authors: Manzano A.C. , Morillo A.J. , Vallejo J.M. , Bayona M.P.
Published: August 2002

A case of thoracopagus conjoined stillborn twins studied with magnetic resonance imaging (MRI) is presented. Due to the parents' denial of authorization for an autopsy of the fetuses, the MRI study was performed as an alternative to necropsy. High‐resolution images of the fetuses demonstrated relevant anatomic features, providing noninvasive pathological insight with preservation of the fetal specimen. J. Magn. Reson. Imaging 2001;13:976–981. © 2001 Wiley‐Liss, Inc.
Fat‐suppressed T2‐weighted MRI of the liver: Comparison of respiratory‐triggered fast spin‐echo, breath‐hold single‐shot fast spin‐echo, and breath‐hold fast‐recovery fast spin‐echo sequences
Authors: Katayama Motoyuki , Masui Takayuki , Kobayashi Shigeru , Ito Tatsuhiko , Takahashi Mamoru , Sakahara Harumi , Nozaki Atsushi , Kabasawa Hiroyuki
Published: August 2002

The purpose of our study was to compare the value of respiratory‐triggered fast spin‐echo, breath‐hold single‐shot fast spin‐echo, and breath‐hold fast‐recovery fast spin‐echo sequences in detecting hepatic lesions. Fat‐suppressed T2‐weighted magnetic resonance (MR) images obtained with the three sequences in 36 patients with 138 lesions and nine patients without lesions were prospectively analyzed. Quantitative and qualitative analyses, including receiver operating characteristic (ROC) analyses, were performed. The mean lesion‐to‐liver contrast‐to‐noise ratio (CNR) for hepatic lesions was highest with the respiratory‐triggered fast spin‐echo sequence. On the basis of receiver‐operating characteristic analyses, tumor detection rates were higher with the breath‐hold fast‐recovery fast spin‐echo sequence (Az = 0.94) than with the respiratory‐triggered fast spin‐echo sequence (AZ = 0.80, P < 0.0001) or the single‐shot fast spin‐echo sequence (Az = 0.77, P < 0.0001). The image quality with the breath‐hold fast‐recovery fast spin‐echo sequence was acceptable in all patients. The breath‐hold fast‐recovery fast spin‐echo sequence provided the highest tumor detection in a short imaging time, although the mean lesion‐to‐liver CNRs were inferior to those of the respiratory‐triggered fast spin‐echo and the breath‐hold single‐shot fast spin‐echo sequences. J. Magn. Reson. Imaging 2001;14:439–449. © 2001 Wiley‐Liss, Inc.
Serial cine‐magnetic resonance imaging of left ventricular remodeling after myocardial infarction in rats
Authors: Nahrendorf Matthias , Wiesmann Frank , Hiller Karl‐Heinz , Hu Kai , Waller Christiane , Ruff Jan , Lanz Titus E. , Neubauer Stefan , Haase Axel , Ertl Georg , Bauer Wolfgang R.
Published: August 2002

The purpose of the present study was the serial investigation of morphological and functional changes after left coronary artery ligation in the intact rat using cine‐magnetic resonance imaging (MRI). MRI studies were performed 4, 8, 12, and 16 weeks after myocardial infarction (MI) with an echocardiogram (ECG)‐triggered cine‐fast low‐angle shot (FLASH)‐sequence in a 7‐Tesla magnet. MI‐size, left ventricular (LV) mass and volumes, cardiac index, ejection fraction (EF), and remote wall and scar thickness of 11 Wistar rats were compared to four sham‐operated rats. Stress MRI with dobutamine (10 μl/kg × minute) was performed at 16 weeks. In MI groups (small MI < 30%, N = 5, large MI > 30%, N = 6), there was significant increase of LV mass (small MI + 47.8% increase, large MI + 74.1%) and wall thickness (large MI 1.21 ± 0.03 to 1.84 ± 0.07 mm). Scar thickness declined from four to 16 weeks (large MI 0.92 ± 0.06 to 0.38 ± 0.02mm, P < 0.05). End‐diastolic volume of both MI groups was significantly elevated but increased further only in animals with large MI from four to 16 weeks (657.1 ± 38.6 to 869.7 ± 60.7 μL, P < 0.05). Compared to sham, EF was significantly depressed in MI (large MI 31.5 ± 2.0%). Wall thickening declined from four to 16 weeks post‐MI (large MI 50.9 ± 9.9 to 28.9 ± 4.4%, P < 0.05). During stress, sham and MI rats increased wall thickening from 66.5 ± 8.2 to 111.2 ± 6.7% and from 30.8 ± 4.3 to 47.5 ± 5.8%, respectively (P < 0.05). Hypertrophy was found in all animals with MI throughout the entire period of observation, whereas dilatation after four weeks was only detected in animals with large MI. These morphologic changes were accompanied by an early decline of EF; myocardial function characterized by wall thickening deteriorated later. J. Magn. Reson. Imaging 2001;14:547–555. © 2001 Wiley‐Liss, Inc.
Mass spectrometry in coupling with affinity capture–release and isotope‐coded affinity tags for quantitative protein analysis
Authors: Tureček František
Published: August 2002

Affinity capture–release electrospray ionization mass spectrometry (ACESIMS) and isotope‐coded affinity tags (ICAT) are two recently introduced techniques for the quantitation of protein activity and content with applications to clinical enzymology and functional proteomics, respectively. One common feature of these methods is that they use biotinylated tags that function as molecular handles for highly selective and reversible affinity capture of conjugates from complex biological mixtures such as cell homogenates and sub‐cellular organelles. ACESIMS uses synthetic substrate conjugates specifically to target cellular enzymes that, when deficient, are the cause of genetic diseases. Multiplex determination of enzyme activities is used for the diagnosis of lysosomal storage diseases. The ICAT method relies on selective conjugation of cysteine thiol groups in proteins, followed by enzymatic digestion and quantitative analysis of peptide conjugates by mass spectrometry. Another common feature of the ACESIMS and ICAT approaches is that both use conjugates labeled with stable heavy isotopes as internal standards for quantitation. Selected applications of the ACESIMS and ICAT techniques are presented that include molecular‐level diagnosis of genetic diseases in children and quantitative determination of protein expression in cells. Copyright © 2001 John Wiley & Sons, Ltd.
Predominance of genotype A HBV in an HBV‐HIV‐1 dually positive population compared with an HIV‐1–negative counterpart in Japan
Authors: Koibuchi Tomohiko , Hitani Akihiro , Nakamura Tetsuya , Nojiri Noriyuki , Nakajima Kazunori , Jyuji Takeo , Iwamoto Aikichi
Published: August 2002

Hepatitis B virus (HBV) has seven genotypes, A to G. Previous studies have shown that genotype C is the most prevalent strain in chronic HBV carriers in East Asia. This study was undertaken to investigate the epidemiology of HBV genotypes among Japanese patients who are coinfected with human immunodeficiency virus type 1 (HIV‐1). The sequences of the complete hepatitis B surface antifen (HBsAg) genes were obtained from 18 coinfected Japanese patients. Among the 18 patients, 12 of 13 men who had sex with men (MSM) had genotype A (92%), whereas only one of five heterosexual or hemophiliac patients had genotype A. The predominance of genotype A HBV in MSM showed a striking contrast to the current genotype prevalence in the Japanese population. Owing to the recent decrease in the rate of vertical transmission in Japan, the role of sexual behavior in the transmission of HBV cannot be overestimated. Thus, the relative proportion of genotype A may gradually increase in Japan. J. Med. Virol. 64:435–440, 2001. © 2001 Wiley‐Liss, Inc.
Clearance kinetics of hepatitis C virus under different antiviral therapies
Authors: Torre Francesco , Giusto Rosella , Grasso Alessandro , Brizzolara Renata , Campo Nadia , Sinelli Nicoletta , Balestra Vincenzo , Picciotto Antonino
Published: August 2002

Interferon alpha (IFN) has been the standard treatment for hepatitis C virus (HCV) infection. Using the kinetic curves of viral clearance, this study compared three treatment regimes based on IFN alone or in combination with Amantadine or Ribavirin to determine the mechanisms of action and the most suitable way to use these drugs. The early clearance kinetics of HCV were studied in 22 patients with chronic hepatitis C under different antiviral treatments: IFN 3 MU daily (7 pts); IFN 3 MU daily plus Amantadine 200 mg (7 pts); and IFN 3 MU daily plus Ribavirin 1–1.2 gr (8 pts), for 6 months. HCV‐RNA was assessed qualitatively and quantitatively on serial samples. The HCV‐RNA decay curves suggested a different behaviour of viral clearance induced by the three treatments. While no significant differences were present in the first 6 hours, between 6 to 12 hours Ribavirin induced a rapid decline in the viral load. Amantadine seemed to accelerate it in the third phase (12 to 30 hours) and to provoke a more pronounced viral decline when compared to IFN alone (P < 0.05) or to IFN plus Ribavirin (P < 0.025) (baseline to 30 hours). Thus, while IFN remains the principal antiviral drug, Amantadine upholds the viral decline. Ribavirin, although synergistic with IFN, does not seem to improve the IFN effect during the earliest phase of treatment but probably supports the effects of IFN later on. A new dynamic approach to HCV treatment can therefore be developed. J. Med. Virol. 64:455–459, 2001. © 2001 Wiley‐Liss, Inc.
The mortar edge element method on non‐matching grids for eddy current calculations in moving structures
Authors: Rapetti F.
Published: August 2002

The subject presented in this paper concerns the approximation of the eddy current problem in non‐stationary geometries with sliding interfaces. The physical system is supposed to be composed of two solid parts: a fixed one (stator) and a moving one (rotor) which slides in contact with the stator. We consider a two‐dimensional mathematical model based on the transverse electric formulation of the eddy currents problem in the time domain and the primary unknown is the electric field vector. The first‐order approximation of the problem that we propose here is based on the mortar element method combined with the edge element discretization in space and an implicit Euler scheme in time. Numerical results illustrate the accuracy of the method and allow to understand the influence of the rotor movement on the currents distribution. Copyright © 2001 John Wiley & Sons, Ltd.
High extracellular γ‐aminobutyric acid protects cultured neurons against damage induced by the accumulation of endogenous extracellular glutamate
Authors: Velasco Iván , Tapia Ricardo
Published: August 2002

The glutamate uptake inhibitor L‐trans‐2,4‐pyrrolidine‐dicarboxylate (PDC) induces glutamate accumulation and neuronal damage in cultured cells. We have used dissociated cortical cells in culture to study whether the toxicity induced by inhibiting glutamate uptake with PDC could be blocked by the simultaneous inhibition of γ‐aminobutyric acid (GABA) uptake, because both types of transporters are affected during an ischemic event. After 6 hr of exposure to 100 μM GABA or to four different GABA uptake inhibitors, the concentration of extracellular GABA was augmented from the basal 2 μM value to about 25 μM and 5 μM, respectively. These increases, however, did not result in protection against the neuronal damage induced by the accumulation of extracellular glutamate because of the simultaneous exposure to PDC. In contrast, when 100 μM GABA and an inhibitor of GABA uptake were added, after 6 hr the concentrations of GABA reached 50 μM, and neurons were protected from PDC‐induced toxicity. The addition of the GABAA and GABAB receptor agonists muscimol and baclofen also partially protected against PDC‐induced damage. The results suggest that the excitotoxic damage resulting from chronic gradual elevation of extracellular glutamate may be prevented by high concentrations of extracellular GABA, an effect mediated by activation of GABAA and GABAB receptors. © 2002 Wiley‐Liss, Inc.
Recent studies on the roles of antiglycosphingolipids in the pathogenesis of neurological disorders
Authors: Ariga Toshio , Miyatake Tadashi , Yu Robert K.
Published: August 2002

Evidence is mounting to suggest a causal role of humoral immunity arising from antiglycosphingolipid (GSL) antibodies in a variety of neurological disorders. These disorders include the demyelinating and axonal forms of Guillain‐Barre syndrome, multifocal motor neuropathy, chronic inflammatory demyelinating polyradiculoneuropathy, and IgM paraproteinemia. Many claims have been made regarding other neurological disorders, which should be carefully scrutinized for their validity, based on several criteria proposed in this review. These criteria include 1) characterization of the causative antigens and immunoglobulins, 2) correlation of the pathological lesions and clinical manifestation of the antigens, 3) establishment of animal models using pure GSLs as the antigens, 4) immunopathogenic mechanisms of the neurodenerative process, 5) mechanisms for the malfunctioning of blood–nerve barrier and the ensuing leakage of circulating antibodies into peripheral nerve parenchyma, and 6) the roles of anti‐GSL antibodies that may cause humorally mediated nerve dysfunction and injury as well as interference with ion channel function at the node of Ranvier, where carbohydrate epitopes are located. Finally, the origin of the anti‐GSL antibodies is discussed in light of the recent circumstantial evidence pointing to a molecular mimicry mechanism with infectious agents. With a better understanding of the immunopathogenic mechanisms, it will then be possible to devise rational and effective diagnostic and therapeutic strategies for the treatment of these neurological disorders. J. Neurosci. Res. 65:363–370, 2001. © 2001 Wiley‐Liss, Inc.
Identification of a positive regulatory element in the myelin‐specific promoter of the PMP22 gene
Authors: Hai Mehreen , Bidichandani Sanjay I. , Patel Pragna I.
Published: August 2002

Over‐ and under expression of the 22 kDa peripheral myelin protein (PMP22) results in dysmyelinating peripheral neuropathies, such as Charcot‐Marie‐Tooth disease type 1A (CMT1A) and hereditary neuropathy, with the liability to pressure palsies (HNPP). Expression of the PMP22 gene is driven by two alternative promoters, P1 and P2, with transcripts originating from P1 associated with peripheral nerve myelination by Schwann cells. Transient transfections of constructs containing P1 (3.5 kb) or P2 (2.5 kb) resulted in high levels of reporter gene expression in the RT4‐D6P2T schwannoma cell line. Serial deletions of P1 revealed that region P1‐A (–105 to –43), situated upstream of the minimal promoter, contained a positive regulatory element. The 62 bp P1‐A region conferred in cis a sevenfold increase in expression of luciferase driven by a heterologous promoter in an orientation‐dependent manner. Interspecies comparison of the P1‐A region revealed a 98% degree of identity between the human, mouse, and rat sequences. A prominent sequence‐dependent DNA–protein complex (C‐I) was detected in electrophoretic mobility shift assays with P1‐A using RT4‐D6P2T nuclear extract and was localized to a minimal 21 bp region within P1‐A. Site‐directed mutagenesis of this region revealed nucleotides at positions –46 to –43 as being necessary for formation of C‐I. Functional analysis of the mutated P1‐A element indicated that positions –46 and –45 were essential for transactivation mediated by this element. Characterization of the transacting factor(s) interacting with this key regulatory element will shed light on its role in regulating peripheral nerve myelination. J. Neurosci. Res. 65:508–519, 2001. © 2001 Wiley‐Liss, Inc.
The analysis of El Niño and La Niña signals in streamflows of Turkey
Authors: Kahya Ercan , Çağatay Karabörk M.
Published: August 2002

A group of earlier investigations has identified some specific regions over the world in which hydrometeorological surface parameters (i.e. precipitation and streamflow) appear to have consistent relationships with the extreme phases of the Southern Oscillation (SO). This paper examines a climatic link between the monthly streamflows in Turkey and the tropical El Niño and La Niña events using a large data set and comprehensive empirical methodology. Coherent and significant streamflow responses were detected in two core regions, namely the northwestern Anatolia (NWA) and the eastern Anatolia (EA). The areal extent of both regions with a defined seasonal signal for the case of each tropical event was determined. Some subregions whose indications are considered to be better than those for the whole core region were also isolated within the core region. In the Susurluk subregion identified in the NWA, the April–October seasonal positive streamflow anomalies were found to have a highly significant relation with the El Niño events. Although there is a possibility that the NWA region is influenced by the El Niño events, this was not confirmed by the hypergeometric test used to assign a significance level for the relationship. A similar analysis has shown that the La Niña events have no noticeable influences on streamflows in the NWA. For the EA region, above normal conditions have been observed during the April(0)–November(0) period and the May(0)–February(+) period for the El Niño and La Niña events, respectively. Moreover, the annual cycle analysis somewhat implies a modulation of regional streamflow in the core regions during the signal period. In some parts of the core regions, correlation results confirm these signals. The results of this study are discussed and are said to be in agreement with the most relevant previous studies concerning precipitation to understand complex global circulation dynamics. In conclusion, mid‐latitude streamflow responses to the extreme phases of SO are detectable over Turkey. Copyright © 2001 Royal Meteorological Society
DFT/MRCI calculations on the excited states of porphyrin, hydroporphyrins, tetrazaporphyrins and metalloporphyrins
Authors: PARUSEL ANDREAS B. J. , GRIMME STEFAN
Published: August 2002

A combination of density functional theory and multi-reference configuration interaction methods (DFT/MRCI) has been applied to the calculation of electronic absorption spectra in a series of porphyrin-type molecules. The calculated excitation energies and oscillator strengths for free-base porphyrin ( PH 2) are in excellent agreement with experiment for both lower and higher excited states which are characterized by a significant contribution of double excitations (>20%). The 41 B 2 u , 41 B 3 u , and 51 B 2 u states are assigned to the L-band and the 71 B 3 u state to the M-band. The results for the hydroporphyrins chlorin ( CH 2) and bacteriochlorin ( BH 2) are in agreement with the experimentally observed increase in intensity for the Q-bands relative to PH 2. For BH 2 we predict a red shift of the Q x -band (0.2 eV) and a blue shift of the B-band (0.5–0.7 eV) in comparison to both PH 2 and CH 2. For porphyrazine ( PzH 2) and the commercial pigment phthalocyanine ( PcH 2) the calculated oscillator strengths of the Q- and B-bands are of comparable size explaining the intense color of PcH 2. For the metalloporphyrins with magnesium ( PMg ) and zinc ( PZn ), the x- and y-polarized components of the Q- and B-bands collapse, due to the higher D4 h symmetry of the molecules. The calculations reproduce the slight, experimentally observed increase in the oscillator strength of the Q-band and the decrease for the B-band. These effects are ascribed to the electropositive nature of the metals relative to hydrogen. Except for the Q-bands, which are adequately described by the 'four-orbital model,' it is essential to account for excitations outside the four frontier orbitals as well as double and triple excitations for accurate reproduction of experimental data. We compare our results both with experiment and, where available, recent first-principle SAC-CI, MRMP, and TDDFT calculations.
Lithium rechargeable batteries composed of octacyanophthalocyaninatoiron and its polymer complex as cathode
Authors: KIM SOO-JONG , ONISHI KEN , MATSUMOTO MICHIKO , SHIGEHARA KIYOTAKA
Published: August 2002

Highly pure octacyanophthalocyaninatoiron complex ( FePcOC ) was synthesized by the reaction between tetracyanobenzene and iron(II) acetate in sulfolane. The complex was further converted into a coordination polymer by the reaction with tetrazine as an axial μ-bridge ligand. The charge/discharge characteristics of lithium cells with an FePcOC cathode were studied. The capacity and the energy density based on the quantity of cathode active material were ca 105 mAh g-1 and 210 Wh kg-1 respectively. Better results were obtained when the cathode material was replaced by the coordination polymer. It was found that the FePcOC and corresponding polymer complex are promising candidates as an active cathode material for lithium secondary batteries.
The relationship between total quality management (TQM) and corporate strategy: the strategic impact of TQM
Authors: Leonard Denis , McAdam Rodney
Published: August 2002

This paper examines the relationship between Total Quality Management (TQM) and Corporate Strategy by investigating the strategic impact of TQM on organizations. There is a paucity of in‐depth research examining this complex relationship.

The research methodology is a grounded theory inductive approach involving nineteen case studies. In this approach the dialogue and storytelling within the research study enables key constraints and areas of interest in the TQM/Strategy discourse to emerge.

The key findings indicate that: (1) in many cases the bureaucratic/functional approach to strategy is paralleled in the approach to TQM; (2) a number of organizations had difficulty in identifying the ‘driving’ influences of TQM in relation to corporate strategy; (3) TQM is found to be a useful catalyst for developing corporate strategy; (4) some organizations were found to restrict their TQM efforts to operational levels rather than adopting Strategic Total Quality Management.

Copyright © 2001 John Wiley & Sons, Ltd.
The effect of drying on black tea quality
Authors: Temple S J , Temple C M , Boxtel A J B van , Clifford M N
Published: August 2002

Drying is an important part of tea manufacture, where enzyme reactions in earlier phases are terminated by heat and moisture loss, and new compounds are produced by the action of heat. This work is an attempt to quantify the temperatures required to produce the desired changes without damage through exposure to excess heat. Experiments were carried out giving already‐dried tea further heat exposure, drying tea from wet dhool in a thin layer, and drying a larger sample in a batch fluidized bed dryer. Temperatures in the range of 60–140 °C were used. Effects were monitored by commercial tasters, thin layer chromatography, reverse phase HPLC and size exclusion HPLC. Exposure to at least 80 °C was found to be necessary for quality development. For periods of less than 1 min, tea particle temperatures of up to 120 °C may be tolerated, but, in general, temperatures of 110 °C and above may be considered deleterious. Inlet air temperatures may be in excess of these values, but only while drying rates are high. The stewing phenomenon, cited by several authors, could not be found when drying times of less than 15 min were used.

© 2001 Society of Chemical Industry
Physicochemical properties and application of pullulan edible films and coatings in fruit preservation
Authors: Diab Tony , Biliaderis Costas G , Gerasopoulos Dimitrios , Sfakiotakis Evangelos
Published: August 2002

The effects of water, sorbitol and a sucrose fatty acid ester (SE) on the water sorption behaviour and thermal and mechanical properties of pullulan‐based edible films as well as the physiological responses of fruit coated with pullulan have been studied. Incorporation of sorbitol or SE in pullulan films resulted in lower equilibrium moisture contents at low to intermediate water activities (aw), but much higher moisture contents at aw > 0.75; estimates of monolayer values (within 4.1–5.9 gH2O kg−1 solids) were given by application of the Brunauer–Emmett–Teller (BET) and Guggenheim–Anderson–DeBoer (GAB) models. A single glass–rubber transition (Tg), attributed to the polysaccharide component, was detected by calorimetry and dynamic mechanical thermal analysis (DMTA) at a sorbitol level of 15–30% DM. With both tests the strong plasticising action of water and polyol was evident in the thermal curves, and the Tg vs moisture content data were successfully fitted to the Gordon–Taylor empirical model. Multifrequency DMTA measurements provided estimates for the apparent activation energy of the glass transition in the range of ˜ 300–488 kJ mol−1. With large‐deformation mechanical testing, large decreases in Young's moduli (tensile and three‐point bend tests) were observed as a result of water‐ and/or polyol‐mediated glass‐to‐rubber transition of the polymeric films. In the moisture content range of 2–8%, increases in flexural modulus (E) and maximum stress (σmax) with small increases in moisture content were found for films made of pullulan or pullulan mixed with 15% DM sorbitol; a strong softening effect was observed when the water content exceeded this range. Addition of sorbitol increased the water vapour transmission rate of the films, whereas addition of SE had the opposite effect. Application of a pullulan/sorbitol/SE coating on strawberries resulted in large changes in internal fruit atmosphere composition which were beneficial for extending the shelf‐life of this fruit; the coated fruit showed much higher levels of CO2, a large reduction in internal O2, better firmness and colour retention and a reduced rate of weight loss. In contrast, similar studies on whole kiwifruits showed increased levels of internal ethylene, which caused acceleration of fruit ripening during storage.

© 2001 Society of Chemical Industry
Chemometric analyses of ‘Golden Smoothee’ apples treated with two preharvest calcium spray strategies in the growing season
Authors: Benavides A , Recasens I , Casero T , Puy J
Published: August 2002

Chemometric techniques were used to analyse the effects of two preharvest calcium strategies applied to increase the calcium content and improve the quality of Golden Smoothee apples after prolonged storage in controlled atmosphere, ultralow‐oxygen (CA‐ULO; 1% O2, 2% CO2) conditions. In a two‐year study the strategies applied by sprays were started 10 and 60 days after full bloom (DAFB) with 10 and six calcium sprays respectively at 15 day intervals throughout the growing season. The most effective results for increasing the calcium content of the apples were attained when the calcium was applied from 60 DAFB with six sprays. Although the chamber effect and mainly the length of storage differentiate the fruits much more than the calcium spray strategies, the evaluation of the results suggests that calcium and firmness remain correlated for up to 4 months of cold storage under CA‐ULO conditions. The effect of calcium decreases with storage time. Titratable acidity and bitter pit incidence correlated negatively with calcium content in year 2. Comparison of the results obtained in the two years indicates that the relationship between calcium and the quality attributes depends not only on the calcium content per se, but also on other factors such as the nutritional status.

© 2001 Society of Chemical Industry
The effectiveness of environmental interpretation at resource‐Sensitive tourism destinations
Authors: Kuo I‐Ling
Published: August 2002

The process of appropriate visitor management is an integral part of sound tourism management. Visitor management includes the development and implementation of rules and regulations with respect to visitor activity, which in turn provides the guidelines for visitors. On the other hand, it also aims to create enjoyable visitor experiences in the hope that visitors will appreciate the value of the site. Environmental interpretation in a resource‐sensitive tourism destination is considered to be an effective visitor management strategy that helps to encourage visitors to adopt more appropriate behaviour in order to sustain the development of tourism. This paper aims to examine the processes and purposes of visitor management and environmental interpretation, including relevant definitions and functions. The characteristics of visitor management and environmental interpretation, and how to increase their effectiveness, also are addressed. Copyright © 2002 John Wiley & Sons, Ltd.
Detailed combustion kinetics of cyclopentadiene studied in a shock‐tube
Authors: Burcat Alexander , Dvinyaninov Michael , Olchanski Erna
Published: August 2002

Mixtures of cyclopentadiene and oxygen diluted in argon were used to obtain ignition delay data in a single pulse shock‐tube. The temperatures ranged from 1278–2110 K and the experimental pressures were between 2.43 and 12.45 atm. The fuel concentrations ranged from 0.5 to 2.5% and the oxygen concentrations were between 3.3 and 16.6%. A Semenov ignition delay expression was determined:
τ = 10−12.5 exp(+34500/RT) [C5H6]0.06 [O2]−0.95 [Ar]0.29 sec
The concentrations are in mol/cc and the activation energy is in cal/mol. Gas‐chromatographic analyses were run on samples quenched before the ignition. The kinetics of combustion of cyclopentadiene was modeled with a full scheme containing 439 elementary reactions and a reduced scheme containing 125 reactions. Both ignition delay times and product distribution served as modeling targets. The mechanism of combustion of cyclopentadiene is discussed in connection to the combustion of aromatic fuels. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 491–508, 2001
Selective removal of residual composite from dental enamel surfaces using the third harmonic of a Q‐switched Nd:YAG laser
Authors: Alexander Robert , Xie John , Fried Daniel
Published: August 2002

Background and Objective

Conventional methods of residual composite removal after the debonding of orthodontic brackets involve the use of abrasives that damage the underlying enamel. The objective of this study was to demonstrate that 355‐nm laser pulses with a pulse width of 10 ns are well suited for the removal of composite through selective laser ablation.

Study Design/Materials and Methods

The residual composite remaining on the surface of extracted human third molars and bovine incisors was removed using multiple laser pulses from the third harmonic (355‐nm) of a Q‐switched Nd:YAG laser.

Results

There is selective ablation of composite from the enamel surface without any discernable damage to the underlying enamel.

Conclusion

This study demonstrates that 355‐nm, 10 ns laser pulses can be used for the selective ablation of dental composite without thermal or mechanical damage to the underlying enamel. Lasers Surg. Med. 30:240‐245, 2002. © 2002 Wiley‐Liss, Inc.
Histologic evaluation of a millisecond Nd:YAG laser for hair removal
Authors: Goldberg David J. , Silapunt Sirunya
Published: August 2002

Background

Hirsutism and hypertrichosis are common problems. Laser‐assisted hair removal has recently become a popular method to remove unwanted hair. However, histologic changes of the hair follicle after exposure to laser continue to require further investigation.

Objective

To determine the thermal effect of a millisecond Nd:YAG hair removal laser.

Methods

Six patients with black hair were treated with 50 msec pulsed Nd:YAG laser at fluences 30, 50 or 100 J/cm2. Histologic examinations were performed on each laser‐treated site at 24–72 hours after laser exposure.

Results

Fluence–dependent selective thermal injury to follicles was seen. The average depth of acute laser injury at fluences 30, 50 and 100 J/cm2 were 1.06, 0.85 and 1.11 millimeters, respectively.

Conclusions

Long‐pulsed millisecond Nd:YAG lasers produce selective thermal damage of hair follicles. Varied laser fluences used in this study did not statistically alter the degree of thermal injury. Lasers Surg. Med. 28:159–161, 2001. © 2001 Wiley‐Liss, Inc.
Are performance appraisals a bureaucratic exercise or can they be used to enhance sales‐force satisfaction and commitment?
Authors: Pettijohn Charles , Pettijohn Linda S. , Taylor Albert J. , Keillor Bruce D.
Published: August 2002

In some sales organizations the performance appraisal is treated as a bureaucratic exercise. As such, sales managers may essentially conduct appraisals in an arbitrary and perfunctory manner. This behavior could be based on the belief that conducting performance appraisals requires considerable amounts of time and effort, generates few rewards, and adds considerably to the manager's level of conflict and stress. The purpose of this research is to examine the relationships existing between performance appraisals, salesperson organizational commitment, and job satisfaction. If various characteristics of performance appraisals that build commitment and satisfaction could be identified, then managers may be more capable of using performance appraisals that yield positive results. A survey of 185 retail salespeople and 58 retail sales managers provided the data required to evaluate the relationship between satisfaction, commitment, and various aspects of performance appraisals. The results of the study indicate that managerially mediated factors may be used to enhance salesperson job satisfaction and organizational commitment. © 2001 John Wiley & Sons, Inc.