bluuebunny/crossref_metadata_2025 huggingface dataset:
Preface: Papers from the 16th International Ecdysone Workshop
Authors: Smagghe Guy , Stanley David
Published: May 2007

We are pleased to introduce a two‐issue set of papers by contributors to the 16th International Ecdysone Workshop held last July in Ghent, Belgium with 128 participants from 18 countries. It would be very difficult to understate the biological significance of ecdysteroids in insect science, and the papers in this Special Issue help us appreciate the continued and rapid progress in this important area. This is also reflected in the fact that nearly 2000 papers were published on “ecdysteroids” in ISI indexed peer‐reviewed international journals over the last 6 years since 2000.

Ecdysteroids do not act on a one‐dimensional hormone‐effect axis. To the contrary, papers in this Special Issue report on ecdysteroid interactions with other signal moieties. Gruntenko et al. and Rauschenach et al. reveal important interactions between biogenic amines and ecdysteroid titers. Eizaguirre et al. bring in new information on interactions of JH and ecdysteroids, while Kamimura et al. write about the influence of ecdysteroids on JH esterase gene expression. Ecdysteroids influence cell death, however, this effect is modulated by JH, as seen in Lobbia et al. As this area develops, we are sure to see new entities—perhaps even eicosanoids—interacting with ecdysteroids.

The mechanisms of ecdysteroids and ecdysteroid biosynthesis continue to fascinate many insect scientists. Dedos et al. report on calcium signal cascades in prothoracic glands. Localization and movement of the ecdysteroid receptor complex draws the attention of Cronauer et al. and Betanska et al. This receptor also has potential biotech application with gene switch technology, as discussed by Tavva et al.

The significance of ecdysteroids in insect biology is highlighted by the number of parasitoids and plants that influence insect ecdysteroids. Rharrabe et al. outline the diversity of detoxification pathways for ingested ecdysteroids, and Bodin et al. report on host‐induced ecdysteroids in a parasitoid. Krishnan et al. report on the influence of ecdysteroids in oxidative stress damage.

Together, the papers in this Special Issue advance our appreciation of the biological significance of ecdysteroids in insect biology and they celebrate the insect scientists who are working on the frontiers of our knowledge in this substantial area. We hope this body of work helps scientists who want to participate in this exciting research.
Peptides derived from Cdk5 activator p35, specifically inhibit deregulated activity of Cdk5
Authors: Kesavapany Sashi , Zheng Ya‐Li , Amin Niranjana , Pant Harish C.
Published: May 2007

Normal Cdk5 activity, conferred mainly by association with its primary activator p35, is critical for normal function of the cell and must be tightly regulated. During neurotoxicity, p35 is cleaved to form p25, which becomes a potent and mislocalized hyperactivator of Cdk5, resulting in a deregulation of Cdk5 activity. p25 levels have been found to be elevated in Alzheimer's disease (AD) brain and overexpression of p25 in a transgenic mouse results in the formation of phosphorylated tau, neurofibrillary tangles and cognitive deficits that are pathological hallmarks of AD. p25/Cdk5 also hyperphosphorylates neurofilament proteins that constitute pathological hallmarks found in Parkinson's disease and amyotrophic lateral sclerosis. The selective targeting of p25/Cdk5 activity without affecting p35/Cdk5 activity has been unsuccessful. In this review we detail our recent studies of selective p25/Cdk5 inhibition without affecting p35/Cdk5 or mitotic Cdk activities. We found that a further truncation of p25 to yield a Cdk5 inhibitory peptide (CIP) can specifically inhibit p25/Cdk5 activity in transfected HEK cells and primary cortical neurons. CIP was able to reduce tau hyperphosphorylation and neuronal death induced caused by p25/Cdk5 and further studies with CIP may develop a specific Cdk5 inhibition strategy in the treatment of neurodegeneration.
A posteriori error estimation of approximate boundary fluxes
Authors: Wildey T. , Tavener S. , Estep D.
Published: May 2007

This paper describes the a posteriori estimation of the error in the flux of a finite element approximation on a piece of the boundary of the domain. The estimate is obtained via a generalized Green's function corresponding to the quantity of interest on the boundary. We investigate the effects of smoothing the data corresponding to the quantity of interest and explore the effective domain of dependence of the quantity. We relate this approach to previous work by M. F. Wheeler, G. F. Carey, I. Babuska et al., and M. Larson et al. Copyright © 2007 John Wiley & Sons, Ltd.
Ligand‐Exchange Processes on Solvated Lithium Cations: DMSO and Water/DMSO Mixtures
Authors: Pasgreta Ewa , Puchta Ralph , Galle Michael , van Eikema Hommes Nico , Zahl Achim , van Eldik Rudi
Published: May 2007

Solutions of LiClO4 in solvent mixtures consisting of dimethylsulfoxide (DMSO) and water, or DMSO and γ‐butyrolactone, were studied by 7Li NMR spectroscopy (for complexation by cryptands in γ‐butyrolactone as a solvent, see: E. Pasgreta, R. Puchta, M. Galle, N. J. R. van Eikema Hommes, A. Zahl, R. van Eldik, J. Incl. Phen., 2007, 58, 81–88). Chemical shifts indicate that the Li+ ion is coordinated by four DMSO molecules. In the binary solvent mixture of water and DMSO, no selective solvation is detected, thus indicating that on increasing the water content of the solvent mixture, DMSO is gradually displaced by water in the coordination sphere of Li+. The ligand‐exchange mechanism of Li+ ions solvated by DMSO and water/DMSO mixtures was studied using DFT calculations. Ligand exchange on [Li(DMSO)4]+ was found to follow a limiting associative (A) mechanism. The displacement of coordinated H2O by DMSO in [Li(H2O)4]+ follows an associative interchange mechanism. The suggested mechanisms are discussed in reference to available experimental and theoretical data.
Ab Initio Static and Molecular Dynamics Study of 4‐Styrylpyridine
Authors: Lawson Daku Latévi M. , Linares Jorge , Boillot Marie‐Laure
Published: May 2007

We report an in‐depth theoretical study of 4‐styrylpyridine in its singlet S0 ground state. The geometries and the relative stabilities of the trans and cis isomers were investigated within density functional theory (DFT) as well as within Hartree–Fock (HF), second‐order Møller–Plesset (MP2), and coupled cluster (CC) theories. The DFT calculations were performed using the B3LYP and PBE functionals, with basis sets of different qualities, and gave results that are very consistent with each other. The molecular structure is thus predicted to be planar at the energy minimum, which is associated with the trans conformation, and to become markedly twisted at the minimum of higher energy, which is associated with the cis conformation. The results of the calculations performed with the post‐HF methods approach those obtained with the DFT methods, provided that the level of treatment of the electronic correlation is high enough and that sufficiently flexible basis sets are used. Calculations carried out within DFT also allowed the determination of the geometry and the energy of the molecule at the biradicaloid transition state associated with the thermal cis⇄trans isomerization and at the transition states associated with the enantiomerization of the cis isomer and with the rotations of the pyridinyl and phenyl groups in the trans and cis isomers. Car–Parrinello molecular dynamics simulations were also performed at 50, 150, and 300 K using the PBE functional. The studies allowed us to evidence the highly flexible nature of the molecule in both conformations. In particular, the trans isomer was found to exist mainly in a nonplanar form at finite temperatures, while the rotation of the pyridinyl ring in the cis isomer was incidentally observed to take place within ≈1 ps during the simulation carried out at 150 K on this isomer.
Structure and Dynamics of a Discotic Liquid‐Crystalline Charge‐Transfer Complex
Authors: Kruglova Olga , Mendes Eduardo , Yildirim Zeynep , Wübbenhorst Michael , Mulder Fokko M. , Stride John A. , Picken Stephen J. , Kearley Gordon J.
Published: May 2007

The structure of the charge‐transfer complex hexakis(n‐hexyloxy)triphenylene‐2,4,7‐trinitro‐9‐fluorenone (HAT6‐TNF) has been characterized by neutron scattering, X‐ray diffraction (XRD), optical microscopy, and dielectric relaxation spectroscopy (DRS). On the basis of these data and the 1:1 stoichiometry, a consistent structure for the complex is proposed. This structure differs markedly from structures previously proposed for similar materials, because the TNF molecules are found to be situated between the discotic columns rather than sandwiched between the discotic molecules of a given column. The addition of TNF to HAT6 is found to stiffen the structure, and quasi‐elastic neutron scattering shows that the local dynamics of the discotic molecules in HAT6‐TNF is slowed by the presence of the TNF molecules. This scenario is consistent with the observation of two VFT‐type (VFT=Vogel–Fulcher–Tamman) dielectric relaxation processes that relate to the columnar glass transition and a polyethylene‐like hindered glass transition originating from the nano‐phase‐separated fraction of the aliphatic tails.
Regional cerebral blood flow after recovery from anorexia or bulimia nervosa
Authors: Frank Guido K. , Bailer Ursula F. , Meltzer Carolyn C. , Price Julie C. , Mathis Chester A. , Wagner Angela , Becker Carl , Kaye Walter H.
Published: May 2007

Objective:

Abnormalities of regional cerebral blood flow (rCBF) have been found in individuals who are ill with anorexia (AN) or bulimia nervosa (BN). Little is known about whether rCBF normalizes after recovery from AN and BN.

Method:

Eighteen control women (CW), 10 recovered restricting type AN, 8 recovered AN with a binging history, and 9 recovered BN participants without a history of AN were studied using positron emission tomography and [15O]water in order to assess rCBF.

Results:

Partial volume corrected rCBF values in cortical and subcortical brain regions were similar between groups. Neither current body mass index nor age correlated with rCBF values.

Conclusion:

The results from this study indicate that rCBF normalizes with long‐term recovery. Thus, altered rCBF is unlikely to confound functional imaging studies in AN or BN after recovery. © 2007 by Wiley Periodicals, Inc. Int J Eat Disord 2007.
Dynamic load balancing for the reduction of network traffic using network transferable computers
Authors: Hiyasuki Megumi , Inoue Shinji , Kakuda Yoshiaki , Toda Kenji , Suzaki Kuniyasu
Published: May 2007

Dynamic load balancing (DLB) making use ofnetwork transferable computers(NTC) and Mobile IP is a new approach to performing load balancing for network traffic. In client– server systems when access requests to a specific server become particularly high from time to time, excessive amounts of network traffic will be generated on the route connecting to the server. With a server that is receiving a high concentration of requests, the provision of a mirror server can help provide load balancing to deal with issues of host performance, but it is not necessarily the best approach when the objective is principally to balance the load of the traffic on the network. In the DLB approach, the server is given the capability to migrate across the network; the server can therefore be moved to a location from which the route over which request and response packets to the server are causing congestion can be avoided. Since this results in the corresponding traffic being eliminated from the given network route, it allows the load balancing of network traffic. The proposed method is constructed via the use of an NTC system, Mobile IP, and a server migration manager. The server migration manager system can provide the following functionality. First, it is able to analyze information obtained from the network in which the server is located and provide predictions necessary for determining migration decisions. Next it can determine whether or not the server should actually migrate and in the case that it does can determine the location to migrate to. We have conducted evaluations of this method in simulation experiments and confirmed that traffic was reduced on the targeted network route. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 90(11): 48– 60, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20345
On‐Off PVC Membrane Based Potentiometric Immunosensor for Label‐Free Detection of Alpha‐Fetoprotein
Authors: Zhou Lu , Yuan Ruo , Chai Yaqin
Published: May 2007

A poly(vinylchloride) (PVC) membrane based potentiometric immunosensor for the direct detection of alpha‐fetoprotein (AFP) has been developed. First, Au colloid particle was chemisorbed upon amino groups of o‐phenylenediamine, which were dissolved in plasticized PVC membrane. Then alpha‐fetoprotein antibody (anti‐AFP) was immobilized upon the surface of the Au colloid particle to prepare a potentiometric AFP immunosensor. The Au colloid particle modified PVC membrane was characterized by digital photo and transmission electron microscope (TEM). The immunosensor exhibited fast potentiometric response (≤4 min) and showed specific response to AFP in the range of 4.9 to 158.5 ng/mL with a correlation coefficient of 0.9971 and a detection limit of 1.6 ng/mL. The factors influencing the performance of the immunosensor were also studied in detail. Moreover, the proposed method is economical and efficient as well as potentially attractive for clinical immunoassays.
A unified approach to the analytical assessment of multi‐user diversity with imperfect channel state information: ergodic capacity and robustness analysis
Authors: Vicario José López , Antón‐Haro Carles
Published: May 2007

In this paper, we explore the combined use of spatial and multi‐user diversity (MUD) in a cellular system where the channel state information (CSI) available at the base station (BS) is subjected to imperfections. To do that, we consider a general statistical approach to describe the degree of CSI imperfection. By doing so, performance assessment is conducted for the generalised case in terms of ergodic system capacity, for which closed‐form expressions are derived. In order to gain some insight, practical examples are presented and spatial versus MUD trade‐offs are analytically assessed. Next, we analyse several design trade‐offs in terms of increased ergodic (long term) system capacity versus robustness to short‐term SNR fluctuations for the transmission schemes under consideration. Copyright © 2007 John Wiley & Sons, Ltd.
Introduction of lymphangiography and percutaneous embolization of the thoracic duct in a stepwise approach to the management of chylous fistulas
Authors: van Goor Arnoud T. , Kröger Robert , Klomp Houke M. , de Jong Marianne A. A. , van den Brekel Michiel W. M. , Balm Alfons J. M.
Published: May 2007

Background.

Chylous fistula occurring after head and neck or thoracic surgery is an uncommon but well‐described complication, with a reported incidence of 1% to 2.5%. Conservative management can be successful and consists of dietary measures combined with suction drainage. This article reports on percutaneous embolization of the thoracic duct through catheterization of the retroperitoneal lymph vessels.

Methods.

Two patients, in whom conservative management for cervical chylous fistula failed, underwent lymphangiography with opacification of the thoracic duct, followed by radioguided catheterization and embolization.

Results.

Embolization was successful in both patients. In 1 patient the procedure had to be repeated once to stop the chylous drainage.

Conclusions.

Radioguided percutaneous catheterization and embolization of the retroperitoneal lymph vessels offers an excellent treatment option for patients with persistent chylous fistulas after failure of conservative management. We revised our stepwise management protocol (de Gier, Head Neck 1996; 18:347–351) and now consider this procedure as the secondary intervention step. © 2007 Wiley Periodicals, Inc. Head Neck 2007
Reducing poverty through fisheries co‐management: an analysis of design and intentions in Uganda
Authors: Nunan Fiona
Published: May 2007

Reducing poverty is the overarching policy objective in developing countries and so policies in all sectors are required to show how they will contribute to poverty reduction—fisheries included. Fisheries co‐management in Uganda has been designed to contribute to poverty reduction through development of an enabling policy framework; improving governance at community and lake wide levels; empowering marginalised stakeholders; and, improving benefits for women and the poor. Challenges for the realisation of poverty‐reduction objectives include financing implementation in a donor‐dependent environment; changing attitudes and securing commitment of local government officials and communities; and, ensuring that empowerment of the ‘marginalised’ is effective. Copyright © 2007 John Wiley & Sons, Ltd.
Adverse influence of brand commitment on consideration of and preference for competing brands
Authors: Desai Kalpesh Kaushik , Raju Sekar
Published: May 2007

This research investigates if commitment towards a target brand limits set size and preference towards competing brands in memory‐based consideration sets across three situations: (1) situations in which the situational goal matches the benefit offered by the target brand; (2) situations in which the situational goal matches the benefit offered by a competitor brand; and (3) situations in which a new benefit is introduced in the category for the first time. Findings confirm the set size and preference biases of committed consumers against a competitor brand in the first two situations. However, in the third situation, committed consumers favorably or unfavorably view the competitor brand depending on whether it is the first brand to introduce the new benefit in the category. © 2007 Wiley Periodicals, Inc.
Comparison of different nucleating agents on crystallization of poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerates)
Authors: Qian Jun , Zhu Linyong , Zhang Jinwen , Whitehouse Robert S.
Published: May 2007

In this study, thymine and melamine were introduced as nucleating agents for poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerates) (PHBVs) and poly(3‐hydroxybutyrate) (PHB), and their effects were compared with that of boron nitride (BN). Because the overall crystallization rate of PHBVs decreases significantly with the increase in the 3‐hydroxyvalerate comonomer content, the study focused on the crystallization of PHBVs. Isothermal crystallization kinetics of the neat PHBVs and the nucleated PHBVs were studied by differential scanning calorimetry (DSC). The Avrami equation was derived and the parameters were assessed for the nucleation and crystal growth mechanism. The nucleation and crystal growth were examined using polarized optical microscopy. All nucleating agents had similar particle sizes and showed good dispersion in the polymer matrix, as revealed by scanning electron microscopy. The results indicated that BN and thymine significantly increased the overall crystallization rate for all PHBVs studied and demonstrated very similar nucleating effects. Melamine reacted with PHBVs and accelerated the thermal degradation, and hence was less effective in nucleating PHBVs. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1564–1577, 2007
Gas barrier of polystyrene montmorillonite clay nanocomposites: Effect of mineral layer aggregation
Authors: Nazarenko S. , Meneghetti P. , Julmon P. , Olson B. G. , Qutubuddin S.
Published: May 2007

Three polystyrene (PS)/clay hybrid systems have been prepared via in situ polymerization of styrene in the presence of unmodified sodium montmorillonite (Na‐MMT) clay, MMT modified with zwitterionic cationic surfactant octadecyldimethyl betaine (C18DMB) and MMT modified with polymerizable cationic surfactant vinylbenzyldimethyldodecylammonium chloride (VDAC). X‐ray diffraction and TEM were used to probe mineral layer organization and to expose the morphology of these systems. The PS/Na‐MMT composite was found to exhibit a conventional composite structure consisting of unintercalated micro and nanoclay particles homogeneously dispersed in the PS matrix. The PS/C18DMB‐MMT system exhibited an intercalated layered silicate nanocomposite structure consisting of intercalated tactoids dispersed in the PS matrix. Finally, the PS/VDAC‐MMT system exhibited features of both intercalated and exfoliated nanocomposites. Systematic statistical analysis of aggregate orientation, characteristic width, length, aspect ratio, and number of layers using multiple TEM micrographs enabled the development of representative morphological models for each of the nanocomposite structures. Oxygen barrier properties of all three PS/clay hybrid systems were measured as a function of mineral composition and analyzed in terms of traditional Nielsen and Cussler approaches. A modification of the Nielsen model has been proposed, which considers the effect of layer aggregation (layer stacking) on gas barrier. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1733–1753, 2007
Interpretation of the polyelectrolyte and antipolyelectrolyte effects of poly(N‐vinylimidazole‐co‐sodium styrenesulfonate) hydrogels
Authors: Valencia Joaquín , Piérola Inés F.
Published: May 2007

Hydrogels of N‐vinylimidazole (VI) and sodium styrenesulfonate (SSS) were synthesized in aqueous solution by radical crosslinking copolymerization with N,N′‐methylene‐bis(acrylamide) as crosslinker. Swelling in several saline solutions was measured for hydrogel samples synthesized with different comonomer concentrations (CT = 10, 25, or 40%) and with SSS mole fractions covering a broad range (fSSS = 0–0.7), while the crosslinker ratio was 2 wt % in all cases. The degree of swelling in aqueous solution with a specific ionic strength (μ), plotted versus the SSS composition of the feed, shows a minimum for any set of samples synthesized with a fixed CT. The dependence of swelling on μ shows both polyelectrolyte (fSSS beyond the minimum) and antipolyelectrolyte behaviors (in the low fSSS limit). It was found that the nonGaussian factor of the crosslinking density and the polymer‐solvent interaction parameter increase with fSSS for any CT. Moreover, in the low fSSS limit, the osmotic swelling pressure is governed not only by the ionic contribution, but also by the polymer‐solvent mixing and, the concentration of mobile counterions inside the gel is not proportional to the net fixed charge but to the addition of cationic and anionic side groups, what discards the formation of ionic pairs. The antipolyelectrolyte effect is interpreted as due to the increasing protonation of VI as μ goes up. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1683–1693, 2007
Molecular dynamics in PVDF/PVA blends as revealed by dielectric loss spectroscopy
Authors: Linares A. , Nogales A. , Rueda D. R. , Ezquerra T. A.
Published: May 2007

The relaxation behavior of a series of compatible poly(vinylidene fluoride) (PVDF) and poly(vinyl acetate) (PVA) blends has been investigated by dielectric spectroscopy in a broad frequency and temperature range. Blends with PVDF content higher than 60% in weight are semicrystalline. Semicrystalline blends show a relaxation (αc) occurring in the crystalline phase of PVDF. Both semicrystalline and amorphous blends exhibit two processes, α and β associated to the overall segmental dynamics and to localized motions in the amorphous phase, respectively. For high PVDF content samples, the β relaxation exhibits an anomalous behavior characterized by a crossover from segmental to local dynamics, upon decreasing temperature, attributed to confinement effects taking place in PVDF segregated regions. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1653–1661, 2007
Significant variations in nuclear structure occur between and within Gleason grading patterns 3, 4, and 5 determined by digital image analysis
Authors: Veltri Robert W. , Marlow Cameron , Khan Masood A. , Miller Michael C. , Epstein Jonathan I. , Partin Alan W.
Published: May 2007

BACKGROUND

Alterations in nuclei structure and DNA content captured from Gleason grading patterns 3, 4 and 5 of radical prostatectomy (RP) cases were determined by a computer‐assisted microscope. Quantitative Nuclear Morphometry (QNM) profiles were created to evaluate variability in nuclear structure within each of these grades.

METHODS

A tissue microarray (TMA) was constructed using RP cases and the prostate cancer (PCa) TMA cores prepared from 20 GG‐3, 9 GG‐4, 10 GG‐5 patterns, and 20 benign cancer‐adjacent cases from RP archival paraffin blocks. Feulgen‐stained nuclei were captured from 0.6 mm spots using the AutoCyte™ system. Pools of 1100 nuclei captured from each test group were used to calculate Multivariate Logistic Regression (MLR) models that generated predictive indices and predictive probabilities (PP) to make comparisons between and within each set of pooled nuclei.

RESULTS

A single QNM profiles yielded areas of receiver operator characteristic curves (ROC) that distinguished differences among benign cancer‐adjacent nuclei and GG‐3 (ROC‐AUC = 0.78); GG‐4 (ROC‐AUC = 0.86) and GG‐5 (ROC‐AUC = 0.88) with accuracies of 73%, 78% and 80% respectively. Applying PP plots generated from MLR models of GG 3, 4, and 5 nuclei clearly demonstrated marked heterogeneity within each of these three GG patterns.

CONCLUSIONS

QNM signatures illustrate alterations in nuclei structure, based upon nuclear morphometry within each of these three GG patterns, and might signify potential variations in PCa disease risk of progression outcomes. In the future a modified system of Gleason grading that considers not only glandular architecture but also quantitative nuclear grade may ensure accuracy in prognosis. Prostate 67: 1202–1210, 2007. © 2007 Wiley‐Liss, Inc.
Effect of metabolic inhibitors on ATP and citrate content in PC3 prostate cancer cells
Authors: Matheson B. K. , Adams J. L. , Zou J. , Patel R. , Franklin R. B.
Published: May 2007

BACKGROUND

In normal prostate epithelial cells low m‐aconitase activity decreases citrate oxidation leading to citrate accumulation. In prostate cancer cells m‐aconitase activity is increased and citrate content is lower. The effect of inhibition of m‐aconitase on ATP production by prostate cancer cells (PC3) is not known nor is the contribution of glycolysis versus respiration.

METHODS

ATP content of PC3 cells as affected by inhibition of m‐aconitase (fluoroacetate (FA), zinc), inhibition of glycolysis (2DxG), or respiration (DNP, oligomycin) was determined. The ability to maintain ATP using glucose or glutamine as sole substrate was also determined. Intermediates including ATP, lactate, glucose, and glutamine were assayed in neutralized perchloric acid (PCA) cell extracts, virgin, and conditioned medium by enzymatic fluorometry.

RESULTS

Data show that inhibition of m‐aconitase, glycolysis, or respiration alone did not decrease ATP content. Inhibition of both glycolysis and respiration were required to decrease ATP content. PC3 cells were able to produce ATP with either glucose or glutamine as sole substrate. Though FA clearly inhibited m‐aconitase there was no evidence that zinc had a similar effect.

CONCLUSION

PC3 cells can support ATP production when m‐aconitase is inhibited by using glycolysis or oxidation of substrate (e.g., glutamine) entering the TCA cycle distal to citrate. Prostate 67: 1211–1218, 2007. © 2007 Wiley‐Liss, Inc.
Analysis of steroid estrogens in water using liquid chromatography/tandem mass spectrometry with chemical derivatizations
Authors: Lin Ying‐Hsuan , Chen Chia‐Yang , Wang Gen‐Shuh
Published: May 2007

Even in trace amounts, estrogens such as 17β‐estradiol (E2), estrone (E1), estriol (E3), and 17α‐ethinyl estradiol (EE2) may have adverse effects on humans and the aquatic ecosystem. Therefore, it is essential to be able to measure trace amounts of steroid estrogens in water. To date, most instruments are not sensitive enough to detect these chemicals in small samples of water. Sensitivity, however, may be improved by using appropriate derivatization reagents to modify the structures of these estrogens so that their ionization efficiency is increased, making them more detectable by liquid chromatography/mass spectrometry (LC/MS). This study uses dansyl chloride, 2‐fluoro‐1‐methylpyridinium p‐toluenesulfonate (FMPTS), and pentafluorobenzyl bromide (PFBBr) as derivatization reagents to react with the phenolic estrogens to make them more detectable in water. We also test how environmental matrices (wastewater effluent, river water, and drinking water) influence the detectability of these estrogens. Both qualitative and semi‐quantitative comparisons of these derivatization methods were made. We found that dansyl chloride derivatives created signal intensities one or two orders of magnitude greater than those normally found in underivatized estrogen standards. The signals derived by FMPTS were analyte‐dependent, and the products derived from E1, E2, and EE2 produced 2.19 to 12.1 times the signal intensity of underivatized E1, E2, and EE2. The product derived from E3 produced weaker signals than that produced by underivatized E3. The PFBBr derivatives produced signals that were as much as 5.8 times those found in the underivatized estrogens. When these derivatization methods were applied to river water, drinking water and effluents from a sewage treatment plant (STP), the different matrices were found to significantly suppress the signals if we used electrospray ionization, though this influence became less significant if we used atmospheric pressure chemical ionization. This study suggests that PFBBr derivatization can best be used for the detection of these estrogens in complex environmental matrices such as river water and STP effluents and that the dansyl chloride derivatization is best used for clean samples such as drinking water. Copyright © 2007 John Wiley & Sons, Ltd.
Analysis of organic acid markers relevant to inherited metabolic diseases by ultra‐performance liquid chromatography/tandem mass spectrometry as benzofurazan derivatives
Authors: Al‐Dirbashi Osama Y. , Santa Tomofumi , Al‐Qahtani Khalid , Al‐Amoudi Mohammed , Rashed Mohamed S.
Published: May 2007

We describe a new approach applicable to the determination of organic acids that serve as diagnostic markers for several inherited metabolic disorders. We utilized liquid chromatography/tandem mass spectrometry for analysis of organic acid derivatives of a recently described benzofurazan reagent. The derivatization step was necessary to obtain organic acid derivatives suitable for analysis by reversed‐phase liquid chromatography with high ionization efficiency for mass spectrometry in the positive‐ion mode. In this work, a group of related dicarboxylic acid markers containing five or six carbon atoms were analyzed and validation was performed for glutaric and 3‐hydroxyglutaric acids, the specific markers for glutaric acidemia type 1. Derivatization was achieved by reacting untreated urine with the derivatization reagent under mild conditions. The reaction mixture was analyzed on a C18 ultra‐performance liquid chromatography (UPLC) column (50 × 2.1 mm, 1.7 µm) and detected in the multiple reaction monitoring mode in 5 min. Calibration curves were linear up to at least 1000 µM with detection limits for glutaric and 3‐hydroxyglutaric acids of 0.025 and 0.02 µM, respectively (signal‐to‐noise ratio of 3). Intra‐day (n = 11) and inter‐day (n = 6) coefficients of variation were better than 11.2%. The assay was successfully applied to control (n = 134) and glutaric acidemia type 1 (n = 55) urine samples. Copyright © 2007 John Wiley & Sons, Ltd.
‘Divine unknowing’: lessons from the Christian mystical tradition for healthcare today
Authors: Tyler Peter M.
Published: May 2007

The article explores the hermeneutic of taking five key facilitating attitudes of the Christian mystical tradition and seeing their relevance to healthcare, pastoral care and psychotherapy/counselling today. The five attitudes are Contemplation, Embodiment, Openness, Integration and Discernment. Each is discussed in turn, drawing on their origins in classical Christian sources and their relevance to contemporary practice. The author argues that in a time of potentially lethal religious conflict they offer an alternative vision of spiritual care. Copyright © 2007 John Wiley & Sons, Ltd.
Closed Form Solutions to Dynamic Punch Problems by Integral Transform Method
Authors: Dhaliwal R. S. , Singh B. M.
Published: May 2007

In this paper we have used integral transform method to obtain a closed form solution of dynamical mixed boundary value problems. We consider an elastic layer with one face lying on a rigid foundation and the other face with two moving punches. Two particular cases of this general problem are considered in detail. The solution for each problem is reduced into triple integral equations with trigonometrical kernel. We have obtained closed form solutions of each set of triple integral equations and closed form expressions for shear stress and contact pressure.
Zur analytischen Lösung geometrischer Optimierungsaufgaben mittels Dualität bei Steuerungsproblemen. Teil I
Authors: Andrejewa J. A. , Klötzler R.
Published: May 2007

Auf der Grundlage der Dualitätstheorie bei Steuerungsproblemen werden Optimalitätskriterien entwickelt und unter Verwendung von Stützfunktionen auf einige geometrische Optimierungsprobleme angewandt. Im ersten Teil steht zur Diskussion die analytische Bestimmung ebener konvexer Bereiche vorgegebener Dicke und vorgegebenen Durchmessers mit maximalen bzw. minimalem Umfang.
Dualität und Strafmethoden bei elliptischen Differentialgleichungen
Authors: Grossmann Ch.
Published: May 2007

Based on a quite general theory for deriving convergence bounds in penalty methods we derive estimations for the influence of penalty and discretization parameters in elliptic differential equations with Dirichlet boundary conditions. Furthermore, starting from an analysis of Brezzi's condition within the framework of optimization some modification of the penalty technique in linear problems is proposed. This modification leads to an improved convergence.
Kinetic Theory of a Gas with Internal Degrees of Freedom
Authors: Jehring L.
Published: May 2007

Applying the moment method of H. Grad, a closed set of balance equations for density, momentum, angular momentum, stress and couple‐stress tensor, and heat flux is derived for a rarefied gas composed of non‐rigid dumb‐bell shaped particles. Averaging these equations over all values of size and orientation of the particles yields new balance equations governing the gas if the structure of the particles changes essentially faster than the position of their centres of mass. In a limiting case the volume viscosity is given in terms of the collision frequency.
Remarks on a One‐Dimensional Stefan Problem Related to the Diffusion‐Consumption Model
Authors: Comparini E. , Ricci R. , Tarzia D. A.
Published: May 2007

We study the behaviour of the free boundary of the Crank‐Gupta model for the diffusion‐consumption of oxygen in a living tissue, assuming an initial condition corresponding to the stationary solution and with a decreasing input of oxygen at the fixed boundary.
Über Korrelationen von Skalaren in homogener isotroper Turbulenz
Authors: Szablewski W.
Published: May 2007

Es wird die Existenz eines Ähnlichkeitsgesetzes für die skalare Zweipunktkorrelation zweiter Ordnung im Trägheits‐Konvektionsbereicht r≪l (l Maß für die Breite der Geschwindigkeits‐ und Skalar‐Korrelation) hergeleitet. Auf der Grundlage des Ähnlichkeitsgestzes, hergeleitet vom Verf. in einer vorangehenden Arbeit, für das skalare Spektrum im Trägheits‐Konvektionsbereich k≫k0 (k0 Wellenzahl der Großen Wirbel) wird für mittlere Prandtlzahlen der Verlauf der skalaren Zweipunktkorrelation zweiter Ordnung und der gemischten (Skalar‐Geschwindigkeit) Zweipunktkorrelation dritter Ordnung mittels Integralrelationen approximative ermittelt. Es ergibt sich eine Ähnlichkeitsstruktur für die Korrelationen. Vergleich mit Messungen.
On the Helmholtz‐Kirchhoff Flow Past an Upstream Facing N‐Segment Channel
Authors: Bentwich M. , Haselgrove M
Published: May 2007

The two dimensional irrotational flow past an upstream facing channel is analysed assuming that an infinitely‐long constant‐pressure cavity trails behind it. The ‘wet’ surface consist of N straight segments of arbitrary lengths which form arbitrary angles one with the other. A dividing streamline emanates upstream and branches at a stagnation point on the wet surface. It is assumed that the two branches separate from the wet surfaces at the outer edges of the first and Nth segments.

Numerical results are obtained for a rectangular channel i. e. N = 3, both angles of π/2 and the two extreme segments of equal lengths. The calculations show that the hydrodynamic pressure gives rise to a moment which tends to position the channel so that its outer flanks are parallel to the free stream.
A Perturbation Method for the Analysis of Torsion of a Compressible Hyperelastic Cylinder
Authors: Tait R. J. , Haddow J. B.
Published: May 2007

A regular perturbation method for the analysis of finite torsion and extension of a compressible isotropic hyperelastic cylinder is proposed. The method is outlined for a particular class of strain energy functions although it can be extended to other classes with some additional complication. Results are obtained for a particular strain energy function for which certain other methods are not applicable and for which a previously proposed perturbation method [1] was unsuccessful. It is assumed that, although the torsion and possibly extension are finite, they are such that the volume strain can be considered infinitesimal. A motivation for the procedure is to examine the behavior of the cylinder as the compressibility of the material approaches zero. Numerical results are given for two different strain energy functions.
Dissipative Rigids in Gyrodynamics
Authors: Rimrott F. P. J.
Published: May 2007

Experimental evidence, from spacecraft behaviour, has shown that the concept of an absolutely rigid body, which has served us so well in the past, apparently no longer suffices to provide for the theoretical treatment of all problems settings in solid mechanics. The purpose of the present paper is to demonstrate that the introduction of a dissipative rigid as a fundamental concept into theoretical mechanics has become a necessity.

Using data from a disabled spacecraft, the paper begins by describing the attitude decay of a gyroscope in detail, using the concept of a dissipative rigid, and its dissipation power, for the theoretical treatment. Against this background, the case for the dissipative rigid body is made in general terms. Each relation bears re‐deriving, and those affected are presented in their new form.

While the concept of a dissipative rigid body is quite general, it can be shown to play a role in gyrodynamics (including impact studies, where it is well established only, a conclusion that explains why its general introduction had to wait until after the advent of the space age.
Lokalisierung der Lösung diskreter Systeme mit instationärer periodischer Nichtlinearität
Authors: Leonow G. A. , Reitmann V.
Published: May 2007

In der vorliegenden Arbeit wird mit der Methode der invarianten Kegel das Stabilitätsverhalten im Sinne von YU. A. Bakaev [1] von diskret wirkenden nichtautonomen Phasensystemen untersucht. Zu den betrachteten Phasensystemen gehören Systeme der automatischen Steuerung mit unstetigen Nichtlinearitäten, die periodisch sind. Mit Hilfe des in der Arbeit bewiesenen Frequenzkriteriums zur asymptotischen Eingrenzung der Phasendifferenz werden Fangregime eines einfachen Impuls‐ und eines Ziffernsystems der Phasensynchronisation analysiert. Diese Vorgehensweise erlaubt von einem einheitlichen Standpunkt aus die explizite Angabe der Attraktoren von Abbildungen der Kreisperipherie in sich, von unstetigen Poincaré‐Abbildungen, wie sie beim Lorenz‐System der konvektiven Turbulenz auftreten, von Punkt‐Mengen‐Abbildungen und von anderen Abbildungsklassen. Der Zusammenhang mit der Chaos‐Theorie wird an einem Beispiel demonstriert.
A New Approach to Some Problems in Potential Theory
Authors: Fabrikant V. I.
Published: May 2007

A new approach is suggested for the solution of mixed boundary value problems in potential theory. Exact solutions in closed form are obtained for a half‐space with a circular line of division of boundary conditions. Several examples are considered to demonstrate the effectiveness of the proposed technique.
Zur Effektivität des Verfahrens der monotonen Iteration bei semilinearen parabolischen und elliptischen Randwertproblemen
Authors: Carl S.
Published: May 2007

Die Effektivität des Verfahrens der monotonen Iteration wird in Abhängigkeit eines bestimmten Iterationsparameters untersucht. Im Ergebnis erhält man mit kleiner werdendem Iterationsparameter eine effektivere Iteration. Der zulässige Bereich für den Iterationsparameter wird angegeben.
Über ein System mit nichtlinearer Parametererregung und Fremderregung
Authors: Tondl A.
Published: May 2007

Ein System mit nichtlinearer Parametererregung und Fremderregung wird analysiert, bei dem die nichtlineare Parametererregung durch das Produkt der Auslenkungskoordinate, ihrer Geschwindigkeit und der harmonischen Funktion gegeben ist. Stationäre Schwingungen in der Hauptresonanz und ihre Stabilität im Großen werden analysiert.
Free Convection in an Infinite Porous Medium Due to a Pulsating Point Heat Source
Authors: Purushothaman R. , Ganapathy R. , Hiremath P. S.
Published: May 2007

Natural convection flow and heat transfer induced by a pulsating point heat source, embedded in an unbounded fluid‐saturated porous medium is studied analytically. Solutions for both the velocity and temperature fields are obtained in the form of series expansions in the Rayleigh number based on the permeability of the porous medium and the mean heat generation rate from the source. All discussions are based on the assumption that the flow is governed by Darcy's law and that the thermal Rayleigh number is small. The fluctuating part shows the evolution of different wave patterns. The interaction of the first harmonic fields induce second‐order mean components in the velocity and temperature fields. Analytical expressions are obtained for the second‐order mean in both the velocity and temperature fields.
On the Decoupling and the Solutions of the Euler Dynamic Equations Governing the Motion of a Gyroscope
Authors: Panayotounakos D. E. , Theocaris P. S.
Published: May 2007

The decoupling and the solutions of the three strongly nonlinear ordinary dynamic differential equations, governing the motion of an arbitrary rigid body, free to rotate about a fixed point (gyro), are presented. The theory developed is based on the assumption that the instantaneous angular velocity and the moment‐components are arbitrary smooth functions of the time. By a quantitative analysis, analytical solutions of the resulting differential equations were obtained under some general conditions in accordance with the physical problem. Finally, a theoretical application is investigated concerning the dynamic response of a one‐axis symmetrical gyroscope subjected to an arbitrary external loading.
On Some Properties of KIVA Numerical Schemes
Authors: Amato U. , Petrillo F.
Published: May 2007

In this paper numerical schemes of the KIVA code for fluid dynamics modeling will be analyzed. In particular consistency and accuracy will be proved. Attention will be paid to the effects of the grid on the numerical properties of the schemes. Moreover, numerical examples will be given in order to show the actual influence of the choice of the grid on the accuracy of the solution.
On the Elasticity Theory of Microporous Solids
Authors: Assaf M. A. , Jentsch L.
Published: May 2007

This paper deals with existence and uniqueness theorems for boundary value problems and a contact problem for a system of differential equations which was suggested by MARKOV as a linear model for microporous solids. The characteristic of this model is that, in addition to the vector of displacement, free dilatation occurs as fourth field quantity independent of the displacement. This free dilatation may be interpreted as porosity of the solid and may play a part in determining zones subjected to the danger of cracking. The boundary integral method is used in proving the existence theorems. Solution representations by potentials are given for all problems, and the boundary integral equations for the density vectors of teh potentials are investigated.
Zum Evolutionsgesetz der kinematischen Verfestigung in objektiver Darstellung
Authors: Backhaus G.
Published: May 2007

Auf der Grundlage der Pragerschen Regel werden Evolutionsgesetze der kinematischen Verfestigung eines starr‐plastischen Materials bei anwendung verschiedener objektiver Zeitableitungen (GREEN, JAUMANN, OLDROYD) erörtert. Die erforderliche Abspaltung der Starrkörper‐Drehung R führt auf die Verwendung der Green‐Naghdi‐Ableitung.

Unter Berücksichtigung der Bauschinger‐Relaxation und eines Einflusses der Materialdrehung der reinen Verzerrung wird das Evolutionsgesetz sowohl für ein raumfestes cartesisches Bezugssystem als auch für das konvektive Basissystem angegeben. In beiden Fällen bleiben in den Gleichungen Rotationsterme. Diese können mittels der polaren Zerlegung des Deformationsgradienten durch reine Deformationsanteile ersetzt werden. Hinsichtlich der auftretenden Variablen besitzen somit die Evolutionsgesetze für das raumfeste Bezugssystem und für das konvektive Basissystem die gleiche Form.
Genericity Analysis for Path‐Following Methods. Application in Unilateral Contact Elastostatics
Authors: Rohde A. , Stavroulakis G. E.
Published: May 2007

Genericity results for sparse parametric optimization problems with equality and inequality constraints are obtained in this paper. Their impact on path‐following (e.g. load incrementation) methods for discretized elastostatic analysis problems with unilateral contact relations are considered in this paper. For the sparse problems which arise after a finite element method discretization, generically appearing singularities along the path of solutions are classified. Perturbations involving only a minimal number of parameters are shown to be sufficient to guarantee genericity. Stability and uniqueness questions for the solution along the path are examined in this way. These results can be used for the solution of inequality mechanics (unilateral) problems by means of load or displacement incrementation techniques; in particular, the choice of appropriate approximation (e.g. order of finite elements) and of the solution algorithm can be based on the results presented here.
Reactions of unsaturated fatty alcohols. I. Preparation and properties of some vinyl ethers
Authors: Teeter H. M. , Dufek E. J. , Coleman C. B. , Glass C. A. , Melvin E. H. , Cowan J. C.
Published: May 2007

A number of vinyl ethers of C18 fatty alcohols have been prepared by reaction of the alcohol with acetylene at atmospheric pressure in the presence of a basic catalyst. Infrared spectroscopic data on long‐chain fatty alcohols, their vinyl ethers, and related chemical derivatives have been obtained. Methods of analysis of long‐chain vinyl ethers for vinyl group have been developed, namely, iodometric, hydroxylamine, and infrared methods.

Preliminary experiments on the polymerization of long‐chain vinyl ethers with ionic catalysts were carried out.