bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis, Characterization and Properties of Poly(1-hexyl-3,4-dimethyl-2,5-pyrrolylene)
Authors: Kim In Tae , Lee Sang Woo , Kwak Tae Hyoung , Lee Jung Youl , Park Hyang Suk , Elsenbaumer Ronald L
Published: January 2003

This paper describes a synthetic approach for the preparation of a soluble new conjugated organic conducting polymer, poly(1-hexyl-3,4-dimethyl-2,5-pyrrolylene) obtained by oxidative coupling reaction of 1-alkyl-3,4-dimethylpyrrole derived from cis-1,4-dibromo-2,3-dimethyl-2-butene and hexylamine.
Synthesis and Spectral Properties of Lithium Naphthalocyanine: A Novel EPR Oximetry Probe
Authors: Manivannan Ayyakkannu , Yanagi Hisao
Published: January 2003

A novel EPR oximetry probe, lithium naphthalocyanine (LiNc) dye has been sythesized successfully and has been characterized using UV–vis spectroscopy, X-ray diffraction and ESR techniques. X-ray diffraction pattern showed the crystalline nature of the synthesized powder and resembles that of typical naphthalocyanine. EPR measurements indicated a linear dynamic EPR line width ranging from 400 mG to 26 G with increasing oxygen concentration.
Formation of p-Aminostyrene Cyclic Tetramer
Authors: Hamaya Takeo , Hayamizu Kikuko , Goto Midori , Komatsuzaki Nobuko , Masuda Takashi
Published: January 2003

Two isomers (1a and 1b) of p-aminostyrene cyclic tetramer (1,9,17,25-tetramethyl-2,10,18,26-tetraaza[2.2.2.2]paracyclophane, 1) were produced from the linear oligomer Pn by passing it through a silica gel column. These are stereochemical isomers (1a: RSRS, meso and 1b: RRSS, meso) and stable in solution. They include two solvent molecules in their crystalline states; 1a includes benzene and 1b includes ethanol.
The First Determination of Spin–Lattice Relaxation Times (T1) of 73Ge in the Solid State
Authors: Takeuchi Yoshito , Nishikawa Miki , Tanaka Katsumi , Takayama Toshio
Published: January 2003

Spin–lattice relaxation times (T1) of 73Ge nuclei of tetraphenylgermane (1) and some other organogermanes in solid state and metallic germanium were determined under the high-resolution condition. T1 values were found in the order of s in agreement with the reported value for metallic germanium determined in the static condition.
Synthesis of Orthorhombic LiMnO2 as a High Capacity Cathode for Li-Ion Battery by Emulsion Drying Method
Authors: Myung Seung-Taek , Komaba Shinichi , Kumagai Naoaki
Published: January 2003

Orthorhombic LiMnO2 was readily synthesized by calcination of an emulsion-dried powder precursor. The optimum synthesis condition to crystallize into zigzag layered β-NaMnO2 system was to calcine at 925 °C for 12 h in an Ar atmosphere. According to TEM observation, the prepared material from the emulsion-dried precursor consisted of highly ordered single crystalline particle. Li/LiMnO2 cell showed the capacity of about 173 mAh (g-oxide)−1 and excellent capacity retention upon cycling with help of cycle-induced spinel like phase, more than 155 mAh g−1 over 300 cycles at 25 °C.
The Self-Assembly of a 3-Component Complex: Solid-State Structure of a 1 : 1 : 1 N,N′-Di(hydroxyethoxyethoxy)pyromellitic Diimide/Dinaphtho-18-crown-6/Water Complex
Authors: Fallon Gary , Langford Steven J , Lee Marcia A-P
Published: January 2003

Dinaphtho-18-crown-6, which contains two π-electron rich dialkoxynaphthalene units, self-assembles with the π-electron deficient N,N′-di(hydroxyethoxyethoxy)pyromellitic diimide in solution to form 1:1 complexes that have the ability to undergo further self-organisation on crystallisation from MeCN/H2O to form linear arrays.
Oxidation of Primary Alkyl Triflates to the Corresponding Aldehydes via Alkoxy(N-tert-butylamino)(methyl)sulfonium Triflates
Authors: Kitagawa Hideo , Matsuo Jun-ichi , Iida Daisuke , Mukaiyama Teruaki
Published: January 2003

Various alkoxy(N-tert-butylamino)(methyl)sulfonium triflates are prepared by selective O-alkylation of N-tert-butylmethanesulfinamide (4c) with primary alkyl trifluoromethanesulfonates (triflates). Successive treatment of thus formed alkoxyaminosulfonium salts with DBU smoothly affords the corresponding aldehydes in good yields. The sequential combination of the two reactions provides a new method for oxidation of primary alkyl triflates to aldehydes, and the present study suggests the existence of alkoxysulfilimines as intermediates of the previously-reported direct oxidation of alcohols by using N-tert-butylphenylsulfinimidoyl chloride (1a) and DBU.
Improvement of Catalyst Durability in Benzene Photooxidation by Rhodium Deposition on TiO2
Authors: Einaga Hisahiro , Futamura Shigeru , Ibusuki Takashi
Published: January 2003

Photocatalytic oxidation of benzene in air was carried out over TiO2 and metal-loaded TiO2 catalysts at room temperature. Deposition of Rh on TiO2 improved the catalyst durability by inhibiting the formation of carbon deposits on the catalyst surface and accelerating their decomposition.
New Ribozyme-Mimics Employing Mg(II) Ion As Catalytic Center
Authors: Kuzuya Akinori , Mizoguchi Ryo , Komiyama Makoto
Published: January 2003

By using two oligonucleotides as cofactors, Mg(II) ion selectively and efficiently hydrolyzed RNA at the target site under physiological conditions. The site-selective hydrolysis was further accelerated by introducing an acridine to oligonucleotides.
Conformational Properties and Intramolecular Weak Interactions in Substituted Dithia[3.3.1]metacyclophanes
Authors: Moriguchi Tetsuji , Inoue Megumi , Sakata Kazunori , Tsuge Akihiko
Published: January 2003

Relationship between conformational properties and intramolecular weak interactions of dithia[3.3.1]metacyclophanes carrying a nitro or an amino group on their inner position was studied by 1H NMR, IR spectra and X-ray structural analyses. It was found out that intramolecular hydrogen-bonding between hydroxy group and one of the methoxy groups or NH–π interaction between amino protons and two opposite aromatic rings exerts a major influence on the conformations of these cyclophanes.
A Highly Efficient Method for the Preparation of the A/B-Ring Component of Phycobilin Derivatives Starting from Bilirubin
Authors: Sawamoto Daisuke , Inomata Katsuhiko
Published: January 2003

An efficient synthetic method of the A/B-ring component of phycobilin derivatives (PΦB and PCB) was established by using bilirubin as a starting material, which allows to construct the phycobilins in a few steps.
Direct Preparation of Rotaxane from Aminoalcohol: Selective O-Acylation of Aminoalcohol in the Presence of Trifluoromethanesulfonic Acid and Crown Ether
Authors: Kihara Nobuhiro , Shin Jong-Il , Ohga Yasuko , Takata Toshikazu
Published: January 2003

Selective O-acylation of aminoalcohols by a bulky acid anhydride in the presence of trifluoromethanesulfonic acid and dibenzo-24-crown-8 afforded [2]rotaxane in high yields. An acid halide could be used as an acylating reagent in the presence of silver trifluoromethanesulfonate.
Gas-Phase Acidities of Cycloheptatrienes: Effects of Alkyl Groups on the Stability of Carbanions
Authors: Mishima Masaaki , Kinoshita Tomomi , Hattori Yoshitaka , Takeuchi Ken'ichi
Published: January 2003

The gas-phase acidities of 7-alkyl substituted cycloheptatrienes have been determined by Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry using a proton-transfer equilibrium method, Δ G0acid (kJ mol−1): methyl 1520.0, ethyl 1516.7, n-propyl acid 1513.3, i-propyl 1512.1, n-butyl 1510.4. The effect of alkyl groups on the acidity of cycloheptatriene is linearly correlated with the polarizability parameters ( σα) of substituents, giving a ρα of–55.3 (kJ σ−1α unit). The magnitude of pa is half of that for RCH3 and is significantly larger than that for the fluorene series. These results suggest that the extent of the charge-delocalization in a carbanion plays an important role in determining the susceptibility of the stability of the carbanion to substituent polarizability effects. In addition, comparison of ρ values of acidities of a series of elemental hydrides shows that the numerical value of ρα decreases in the order, C > O ≈ N > S, and that the change of ρα is related to the stability of the respective parent anions (R = H) rather than the atomic electronegativity at the deprotonation center.
A Mass Spectrometry Investigation of the Conformational Changes in Adrenocorticotropic Hormones
Authors: Lin Hui , Dass Chhabil
Published: January 2003

Electrospray ionization-mass spectrometry (ESI-MS) was employed to study methanol-induced conformational changes in adrenocorticotrophic hormone (ACTH). ACTH, a 39–residue peptide, is a member of the proopiomelanocortin family of peptides. Charge-state distribution (CSD) and hydrogen–deuterium (H/D) exchange were used to monitor the conformational changes as a function of methanol concentration. The latter experiments were conducted via time-resolved ESI-MS in a continuous-flow apparatus. The CSD and the H/D exchange experimental data both reveal that ACTH exists, presumably in a random coil open structure in aqueous media, but assumes a more compact helical conformation with increased concentration of methanol. The H/D exchange experiments also reveal that 79% of ACTH is present as α-helix in mixed water-methanol solvent media.
Conformational Analysis and Binding Affinity Determination for Host—Guest Complexation of Alkali Metal Ions with Bis-Crown Ethers by Electrospray Mass Spectrometry and Molecular Modeling
Authors: Wu Hui-Fen , Huan Shun-Min , Wu Chun-Fu
Published: January 2003

This study presents the application of electrospray ionization mass spectrometry (ESI/MS) to investigate the host–guest complexation phenomenon for an array of alkali metal ions with bis[(benzo-15–crown-5)-15–ylmethyl] pimelate (BBCP). The results have shown that potassium ions possess the best binding affinity with the BBCP, owing to formation of the very stable sandwich-type (1:1) complexes and the strong K+ cation-π electron interactions between the K+ ion and the benzene rings of BBCP. The results of the competition experiments indicate the selectivity for BBCP toward the alkali metal ions is K+ > Rb+ > Cs+ > Na+ > Li+. In addition, combining the results of ESI/MS and molecular mechanics conformational searches reveal that the formation of sandwich-type (1:1) complexes can be observed for larger metal ions including K+, Rb+ and Cs+. As for Na+ ions, both 1:1 and 1:2 complexes can be observed.
Towards An Understanding of the Mechanism of Electron-Capture Dissociation: A Historical Perspective and Modern Ideas
Authors: Zubarev Roman A. , Haselmann Kim F. , Budnik Bogdan , Kjeldsen Frank , Jensen Frank
Published: January 2003

Electron-capture dissociation (ECD) is a new fragmentation technique that utilizes ion–electron recombination reactions. The latter have parallels in other research fields; revealing these parallels helps to understand the ECD mechanism. An overview is given of ECD-related phenomena and of the history of ECD discovery and development. Current views on the ECD mechanism are discussed using both published and new examples.
Can the (M• — X) Region in Electron Capture Dissociation Provide Reliable Information on Amino Acid Composition of Polypeptides?
Authors: Haselmann Kim F. , Budnik Bogdan A. , Kjeldsen Frank , Polfer Nicolas C. , Zubarev Roman A.
Published: January 2003

It has been suggested that small losses from reduced peptide molecular species in electron capture dissociation (ECD) could indicate the presence of certain amino acids [H.J. Cooper, R.R. Hudgins, K. Håkansson and A.G. Marshall, J. Am Soc. Mass Spectrom 13, 241 (2002)], similarly to immonium ions in high-energy collision-activated dissociation. The diagnostic value in ECD of the (M•–X) region (1 Da ≤ X ≤ 130 Da) was tested on several synthetic peptides. The insufficiency of the existing knowledge for making correct conclusions on the amino acid composition is demonstrated and new suggestions of the origin of losses are presented based on the “hot hydrogen atom” ECD mechanism. Generally, it is shown that not only protonation but also charge solvation is responsible for the small losses. The origin of 17 Da and 59 Da losses is revisited and a new mechanism for the 18 Da loss is suggested. The loss of a side chain plus a hydrogen atom is found to be a rather reliable indicator of the presence of histidine, tryptophan, tyrosine and, to a lesser degree, threonine. The overall conclusion is that the (M• - X) region does contain information on the amino acid composition, but extraction of this information requires additional studies.
Multiple Hydrogen Shifts Leading to Ammonia Loss from the Molecular Ions of Cyanocyclohexanes
Authors: Molenaar-Langeveld T.A. , van der Burg A.M. , Ingemann S.
Published: January 2003

The loss of ammonia from the metastable molecular ions of cyclic cyano compounds has been examined with the use of deuterium labeling and tandem mass spectrometry. Loss of ammonia is significant for ionized cyanocyclohexane, 1-methyl-, 4-methyl-, 4-cyano-and 4-phenyl-cyanocyclohexanes, 4-cyanopiperidine, cyanocycloheptane and 2-cyanonorbornane. By contrast, loss of ammonia is of minor importance (or absent) for the molecular ions of cyanocyclopentane, 2-methyl-cyanocyclohexane, 1-phenyl-cyanocyclohexane, 1-cyanocyclohexene, 4-cyanotetrahydrothiopyran, 2-cyano-5-norbornene and isocyanocyclohexane. Deuterium labeling of cyanocyclohexane reveals the occurrence of an H-shift from the 4-position to the cyano function, followed by a 1,2-H shift from the 1-position to the C-atom of the newly-formed–CNH group. Subsequently, a series of H-shifts leads to a distonic ion that is formulated as an N-protonated methylamine attached to a cyclohexadienyl radical. Loss of ammonia ensues and leads to ionized toluene as indicated by collision-induced dissociation experiments. For 4-phenyl-cyanocyclohexane, the metastable ions of the cis- and trans-isomers display, essentially, the same unimolecular chemistry. Briefly, the labeling of 4-phenyl-cyanocyclohexane indicates the following: (i) the H atom at the 4-position of the cyclohexane ring is incorporated, to a minor extent, in the ammonia molecule, (ii) loss of NHD2 predominates in the reactions of the molecular ions of 2,2,6,6-d4-4-phenyl-cyanocyclohexane and (iii) the ionized 3,3,5-d3-labeled species expels mainly NH2D. In addition, the metastable molecular ions of the 4-[d5-phenyl]-cyanocyclohexane expel NH3 and NH2D in a ratio of 35:65. A mechanistic scheme is proposed that is consistent with the labeling results for 4-phenyl-cyanocyclohexane as well as the indicated formation of ionized 4-methylbiphenyl as the product ion of ammonia loss.
Calcium and Peptide Binding to Folded and Unfolded Conformations of Cardiac Troponin C. Electrospray Ionization and Fourier Transform Ion Cyclotron Resonance Mass Spectrometry
Authors: Nousiainen Marjaana , Vainiotalo Pirjo , Derrick Peter J. , Coopera Helen J. , Hoxha Antuan , Fati Dorina , Trayer Hylary R. , Ward Douglas G. , Trayer Ian P.
Published: January 2003

The binding of Ca2+ and of a peptide (N-TnC) to human cardiac troponin C (TnC) and its isolated N- and C-terminal domains has been characterized by electrospray ionization Fourier transform ion cyclotron resonance (ESI FT-ICR) mass spectrometry. The peptide N-TnI corresponds to residues 1–29 of the cardiac-specific N-terminal extension of human cardiac troponin I (TnI). The binding of Ca2+ to intact TnC in the absence of the peptide was found to take a bimodal form with preferred stoichiometries of 1:1 TnC: Ca2+ and 1:3 TnC: Ca2+. It is concluded that TnC existed in two conformational isomers that had different binding affinities for Ca2+: the binding of 3 Ca2+ was characteristic of a folded conformation (TnC A) and the binding of 1 Ca2+ was characteristic of a partially unfolded conformation (TnCB). Both of these conformations contributed to the 8+ (and other) charge states of TnC, and were distinguished on the basis of their different Ca2+-binding affinities and not on the basis of the charge state. In the presence of the peptide, a complex with 1:1: 1 TnC: peptide: Ca2+ stoichiometry was formed.
Free Radicals in Mass Spectrometry. Part I. General Fragmentation Rules for Organic and Organometallic Compounds under Electron Impact
Authors: Ponomarev D.A. , Golovin A.V. , Takhistov V.V.
Published: January 2003

General fragmentation rules for isomerization and fragmentation processes based on firm thermochemical grounds are presented for positive odd- and even-electron ions. The thermochemical approach by ions' and free radicals' heats of formation, appearance and critical energies allowed the unification of many known fragmentation and isomerization processes. It is shown that to describe more than 180 classes of organic and hetero-organic compounds it is sufficient to apply only 21 types of isomerization and fragmentation processes. Most of these types are characterized with a specific mechanism and the stabilization morde for ions and/or neutral species. Many original fragmentation schemes are given. In addition to simple bond cleavages, it was demonstrated that the quasi-equilibrium theory of Eyring et al. Is applicable to each step of the multi-stage rearrangement rather than to the summary rearrangement process.
Recent Developments in the Design and Performance of Road Traffic Noise Barriers
Authors: Samuels Stephen , Ancich Eric
Published: January 2003

This paper deals with some recent developments in the design and performance of roadside barriers that are applied as a means of controlling road traffic noise. It is a review paper that is based on the outcomes of literature and information searches undertaken for and on behalf of the Roads and Traffic Authority of NSW. Some interesting, ongoing developments in the design and performance of traffic noise barriers have been identified. In particular, three types of innovative barrier designs we re identified that appear to offer the potential for increased attenuation without the need for substantial increases in barrier height. Each of these developments is considered in some detail in the paper and recommendations are made of the possibility of pursuing them further.
Bus Transit Terminal Noise and Users' Perceptions
Authors: Koushki P.A.
Published: January 2003

The results of the measurements of noise inside bus transit terminals in Kuwait are presented. Passengers' perceptions of the health impacts of noise are also given. Future terminal traffic growth policies will need to consider the growing annoyance of terminal users with this pervasive urban problem.
Semi-Active Isolators Using Electrorheological/Magnetorheological Fluids
Authors: Choi Young-Tai , Wereley Norman M. , Jeon Young-Sik
Published: January 2003

ER (electrorheological)/MR (magnetorheological) fluids are colloidal suspensions that can control their rheological properties such as viscosity and yield stress in response to external signal. As a result, applications using ER/MR fluids have useful features such as fast response time and continuous control ability. These kinds of inherent advantages of ER/MR fluids trigger a lot of research activities on ER/MR applications including controllable vibration isolation systems, torque-transmission devices, and others. Among them, semi-active ER/MR fluid-based vibration isolators will be studied in this paper. The semi-active isolators can effectively isolate systems from various external disturbances with low power consumption, so that the system should not expose to significant dynamic stress and fatigue damage.
Road Traffic Noise Status in Dhanbad, An Industrial Town of the Coal Belt in India
Authors: Pal A K , Samanta R
Published: January 2003

The increase in fast moving traffic and narrow roads are causing vehicle congestion which results in vehicles moving in low gears, accelerating, stopping and horn blowing, etc. All these are the contributing factors for considerable noise in industrial towns in India. The percentage of heavy vehicles in the traffic stream is also a major factor contributing to high noise levels. This paper delineates the systematic noise investigation in Dhanbad, an industrial town in the coal belt. Out of the six monitoring stations within Dhanbad town – Bank More, Shramik Chawk and Court More stations show maximum LAeq levels [79.0 to 84.1 dB] due to higher number of vehicles. On the other hand, at G.T. Road at Govindpur free flowing traffic outside Dhanbad town registers maximum LAeq[81.0 dB] during evening hour (7.00p.m to 8.00p.m) due to the greater number of heavy vehicles (189). The noise generated within Dhanbad town is more than that of the free flowing highway at Govindpur G.T. Road. A car in general generates 15 -dB (A) less noise than a heavy commercial vehicle. It has also been observed that sudden braking followed by gearing acceleration leads to an increase of 10– 15 dB (A) noise level.

The frequency spectrum analysis reveals that the highway (G.T. Road) noise has a well-defined sound pressure level (SPL) at 63 Hz., representing the firing frequency of the vehicles at high speed. Again, a comparatively less alarming frequency at about 1 kHz may be due to the combined effect of tyres and wind. The alarming SPL for the traffic inside town has been in the range of 63 Hz to 125 Hz due to the lower speed of the vehicles. After that, there is no peak at higher frequency range, indicating that at relatively low speed tyres and wind make a negligible contribution to the noise spectrum.

The Noise Ratings (NR), which represent the annoyance factor, are observed varying from morning to evening. In most of places, NR during the morning session show peak value due to prevalence of dominant high frequency.

Statistical models / relationships between LAeq, total traffic volume per hour (Q) and percentage of heavy vehicles over total vehicles (P) are developed which can be used for the prediction of traffic noise in similar situations.

The authors stress the need of curbing the traffic noise by taking appropriate steps to bring about a smoother traffic flow at moderate speeds and minimum horn blowing. The necessary steps will include widening of roads, diverting the traffic by means of some bypass roads, making traffic one-way, removing the business congestion in the roadway, avoiding or removing inter sections at near by places, etc. Besides, provision of suitable barriers in the sensitive zone of the roadways can go a long war way to reducing the noise situation.
The Influence of In-Vehicle Noise on Speech Recognition for Automotive Voice-Activated Control Systems
Authors: Fish By Dave G.
Published: January 2003

Voice activation provides a safe and convenient method of controlling vehicle systems such as in-car entertainment, telecommunications and climate control. In the fullness of time it is likely that there will be a high demand across all vehicle classes for such systems for a wide range of vehicle control functions. One of the challenges facing their development and introduction into vehicles is that of the in-vehicle noise environment.
Distance dependency of exciton coupled circular dichroism using turn and helical peptide spacers
Authors: Oancea Simona , Formaggio Fernando , Campestrini Sandro , Broxterman Quirinus B. , Kaptein Bernard , Toniolo Claudio
Published: February 2003

Porphyrins are promising chromophores for the investigation of the still unexplored area of 3‐dimensional structural studies of proteins by using the exciton coupled circular dichroism (CD) method. The synthesis, conformational characterization by FTIR absorption and 1H‐NMR, and CD properties are described for a model bis‐porphyrin system based on homooligo‐[L‐(αMe)Val]n peptides as rigid spacers. In particular, the coupled CD phenomenon is experimentally detected, the intensity of which is modulated by the interchromophoric distance. These results extend and integrate those already reported with steroid, dimeric steroid, and brevetoxin bridges. © 2003 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy) 72: 105–115, 2003
Cellular localization of integrin isoforms in phenylephrine‐induced hypertrophic cardiac myocytes
Authors: Kim Dae Joong , Park Sang Hee , Lim Chol Seung , Chun Jang‐Soo , Kim Jin‐Kyu , Song Woo Keun
Published: February 2003

Cardiac hypertrophy is characterized by remodeling of the extracellular matrix (ECM). Integrins are cell‐surface molecules that link the ECM to the cellular cytoskeleton where they play roles as signaling molecules and transducers of mechanical force. To clarify the possible roles of integrins in cardiac myocyte hypertrophy, we investigated the cellular localization and expression of ECM proteins and integrins in both normal cardiac myocytes and phenylephrine‐induced hypertrophic myocytes. Addition of phenylephrine (PE) to cultured neonatal cardiac myocytes induced sarcomeric organization, increase in cell size, and synthesis of the hypertrophic marker, atrial natriuretic factor (ANF). In particular, fibronectin and collagen underwent dramatic localization changes during PE‐induced cardiac hypertrophy. Significant changes were noted in the cellular localization of the respective collagen and fibronectin receptors, integrin α1 and α5, from diffuse to a sarcomeric banding pattern. Expression levels of integrins were also increased during hypertrophy. Treatment with okadaic acid (OA), an inhibitor of protein phosphatase 2A (PP2A), resulted in inhibition of hypertrophic response. These results suggest that dephosphorylation of integrin β1 may be important in the induction of cardiac hypertrophy. Copyright © 2002 John Wiley & Sons, Ltd.
The effects of message framing on behavioral prevalence assumptions
Authors: Stuart Anne E. , Blanton Hart
Published: January 2003

Based on attribution theory and the logic of conversational norms, we predicted that image‐based health communications can alter prevalence estimates for health behaviors. In two studies, participants were exposed either to a positively‐framed or negatively‐framed communication advocating for specific health behaviors. As predicted, participants who read a health communication rated healthy behaviors as less common when positive attributes were associated with healthy choices than when negative attributes were associated with unhealthy choices. The second study revealed that this pattern was most pronounced among participants who reported initial uncertainty about behavioral norms. These findings suggest that positively‐framed influence attempts can promote prevalence assumptions that work against the influence attempt. Copyright © 2002 John Wiley & Sons, Ltd.
Equilibrium real gas computations using Marquina's scheme
Authors: Stiriba Youssef , Marquina Antonio , Donat Rosa
Published: January 2003

Marquina's approximate Riemann solver for the compressible Euler equations for gas dynamics is generalized to an arbitrary equilibrium equation of state. Applications of this solver to some test problems in one and two space dimensions show the desired accuracy and robustness. Copyright © 2003 John Wiley & Sons, Ltd.
The prediction of spatially periodic flows using a finite‐volume model
Authors: Soukkary Tamer El , Straatman Anthony G.
Published: January 2003

A periodic boundary condition has been developed that can be used in conjunction with a specified flow rate to produce accurate results in spatially periodic geometries. This condition is useful in situations where the flow rate is known, or more importantly, in cases where the pressure gradient is not known a priori, such as in countercurrent flows. Using the present condition, the flow rate is imposed at the inlet in terms of a bulk velocity, but the velocity field evolves as part of the solution. The condition is formulated to be suitable for both fixed and moving periodic domains. For the case of a moving domain, a correction is introduced to account for changes in the instantaneous velocity through the periodic edges. Under periodic conditions, these corrections integrate to zero over a complete (temporal) period. The new periodic condition is shown to produce accurate results for flat and wavy‐walled channels under both induced flow and countercurrent conditions. Copyright © 2003 John Wiley & Sons, Ltd.
A numerical method for inverse design based on the inverse Euler equations
Authors: Scascighini A. , Troxler A. , Jeltsch R.
Published: January 2003

We present a numerical method for the inverse shape design of internal flows based on the inverse Euler equations (Keller JJ, Physics of Fluids 1999; 11 and Zeitschrift für Angewandte Mathematik und Physik 1998; 49). We describe an efficient numerical method based on a finite difference discretization and on a Newton–Krylov solver. After showing that the three‐dimensional (3D) inverse Euler equations hold only for complex lamellar flows, we extend the basic axis‐symmetric flow model to handle viscous effects by means of a distributed loss model and to handle quasi‐3D effects by deriving a quasi‐3D formulation of the inverse Euler equations from the passage averaged 3D Euler equations. The coupling of the 2D inverse Euler equations with an integral boundary layer method is presented too. Copyright © 2003 John Wiley & Sons, Ltd.
Estimating zero‐g flow rates in open channels having capillary pumping vanes
Authors: Srinivasan Radhakrishnan
Published: January 2003

In vane‐type surface tension propellant management devices (PMD) commonly used in satellite fuel tanks, the propellant is transported along guiding vanes from a reservoir at the inlet of the device to a sump at the outlet from where it is pumped to the satellite engine. The pressure gradient driving this free‐surface flow under zero‐gravity (zero‐g) conditions is generated by surface tension and is related to the differential curvatures of the propellant‐gas interface at the inlet and outlet of the PMD. A new semi‐analytical procedure is prescribed for accurately calculating the extremely small fuel flow rates under reasonably idealized conditions. Convergence of the algorithm is demonstrated by detailed numerical calculations. Owing to the substantial cost and the technical hurdles involved in accurately estimating these minuscule flow rates by either direct numerical simulation or by experimental methods which simulate zero‐g conditions in the lab, it is expected that the proposed method will be an indispensable tool in the design and operation of satellite fuel tanks. Copyright © 2003 John Wiley & Sons, Ltd.
Ketamine and fMRI BOLD signal: Distinguishing between effects mediated by change in blood flow versus change in cognitive state
Authors: Abel Kathryn M. , Allin Matthew P.G. , Kucharska‐Pietura Katarzyna , Andrew Chris , Williams Steve , David Anthony S. , Phillips Mary L.
Published: January 2003

No human fMRI studies have examined ketamine effects on the BOLD signal change associated with cognitive task performance. We wished to distinguish between effects on 1) cerebral blood flow, with resultant change in BOLD signal; and 2) cognition and neural mechanisms underlying BOLD signal change associated with task performance. Eight right‐handed men (mean age 28.75 years) received ketamine or saline i.v. in a randomized, double‐blind manner (bolus 0.23 mg/kg; 0.5 mg/kg over 45 min to a maximum 1 hr). Subjects viewed 10 alternating 30‐sec blocks of faces with neutral expressions and a fixation cross and discriminated gender of faces. Gradient echo echoplanar images were acquired on a GE Signa 1.5 T Neurovascular system. One hundred T2‐weighted images depicting BOLD contrast were acquired over 5 min (for each task) at each of 14 near‐axial noncontiguous 7‐mm thick planes. Ketamine significantly increased dissociative phenomena and negative symptoms, but did not affect performance of the gender discrimination task. Significant BOLD signal change was demonstrated predominantly in occipitotemporal cortex with both ketamine and placebo. Only two clusters in middle occipital gyrus (BA 18) and precentral gyrus (BA 4) showed significantly decreased BOLD signal change during ketamine compared to placebo. BOLD signal change was not significantly greater in any region during ketamine. Our findings demonstrate subtle rather than major differences between the effects of ketamine and placebo upon the BOLD signal change during perception of face–non face contrast. We suggest that they represent task‐dependent effects of the drug/placebo, rather than task‐independent effects of the drug per se, and indicate that the effects of ketamine on cerebral blood flow are predominantly focal and task‐dependent, rather than global and task‐independent. Hum. Brain Mapping 18:135–145, 2003. © 2002 Wiley‐Liss, Inc.
Spatiotemporal activation of the two visual pathways in form discrimination and spatial location: A brain mapping study
Authors: Rao Hengyi , Zhou Tiangang , Zhuo Yan , Fan Silu , Chen Lin
Published: January 2003

To address the question of the relationship between the two visual pathways, a ventral stream for object and form vision and a dorsal stream for spatial and motion vision, we measured the spatiotemporal activation patterns in the two pathways responding to an integrated visuospatial task to which form discrimination and spatial location were assigned simultaneously. The two cognitive components of form discrimination and spatial location were interwoven in the task; however, the fMRI data demonstrated that such a task still activated both ventral GTi/GF (the inferior temporal gyrus/the fusiform gyrus) and dorsal Ga/PCu (the angular gyrus/Precuneus), which are supposed to mediate form discrimination and spatial location, respectively. In addition, the source waveforms of the fMRI foci based on the source analysis of the fMRI‐seeded dipole modeling and the moving dipole modeling indicated that in responding to the task combining simultaneously form perception and spatial location, the activity in Ga/PCu begins earlier than that in GTi/GF, but it peaks later and lasts longer. Hum. Brain Mapping 18:79–89, 2003. © 2002 Wiley‐Liss, Inc.
Dorsal penile nerve stimulation elicits left‐hemisphere dominant activation in the second somatosensory cortex
Authors: Mäkelä J.P. , Illman M. , Jousmäki V. , Numminen J. , Lehecka M. , Salenius S. , Forss N. , Hari R.
Published: January 2003

Activation of peripheral mixed and cutaneous nerves activates a distributed cortical network including the second somatosensory cortex (SII) in the parietal operculum. SII activation has not been previously reported in the stimulation of the dorsal penile nerve (DPN). We recorded somatosensory evoked fields (SEFs) to DPN stimulation from 7 healthy adults with a 122‐channel whole‐scalp neuromagnetometer. Electrical pulses were applied once every 0.5 or 1.5 sec to the left and right DPN. For comparison, left and right median and tibial nerves were stimulated alternatingly at 1.5‐sec intervals. DPN stimuli elicited weak, early responses in the vicinity of responses to tibial nerve stimulation in the primary somatosensory cortex. Strong later responses, peaking at 107–126 msec were evoked in the SII cortices of both hemispheres, with left‐hemisphere dominance. In addition to tactile processing, SII could also contribute to mediating emotional effects of DPN stimuli. Hum. Brain Mapping 18:90–99, 2003. © 2002 Wiley‐Liss, Inc.
Power spectrum ranked independent component analysis of a periodic fMRI complex motor paradigm
Authors: Moritz Chad H. , Rogers Baxter P. , Meyerand M. Elizabeth
Published: January 2003

Independent component analysis (ICA) has been demonstrated to be an effective data‐driven method for analyzing fMRI data. However, a method for objective differentiation of task‐related components from those that are artifactually non‐relevant is needed. We propose a method of constant‐cycle (periodic) fMRI task paradigm combined with ranking of spatial ICA components by the magnitude contribution of their temporal aspects to the fundamental task frequency. Power spectrum ranking shares some similarity to correlation with an a priori hemodynamic response, but without a need to presume an exact timing or duration of the fMRI response. When applied to a complex motor task paradigm with auditory cues, multiple task‐related activations are successfully identified and separated from artifactual components. These activations include sensorimotor, auditory, and superior parietal areas. Comparisons of task‐related component time courses indicate the temporal relationship of fMRI responses in functionally involved regions. Results indicate the sensitivity of ICA to short‐duration hemodynamics, and the efficacy of a power spectrum ranking method for identification of task‐related components. Hum. Brain Mapping 18:111–122, 2003. © 2002 Wiley‐Liss, Inc.
The changing roles of human capital, state context of residence, and ethnic bonds in interstate migration: American Jews 1970–1990
Authors: Rebhun Uzi
Published: January 2003

Motivated by the gap left by the census, which does not enquire into matters of creed, this study examines the changing role of internal migration determinants among American Jews. Multivariate analysis of data from the 1970/1 and 1990 National Jewish Population Surveys, to which contextual measures were attached, shows a decline over time in the importance of human capital in explaining five‐year interstate migration, while environmental amenity receives increasing consideration; at the same time, ethnic concentration continues to deter migration between states. Ethnic processes have lost much of their power as predictors of future migration. I propose two alternative interpretations of these apparently contradictory findings, and discuss them in the wider context of white ethnicity in America. Copyright © 2003 John Wiley & Sons, Ltd.
Ethnic residential concentration and a ‘new spatial order?’: exploratory analyses of four United States metropolitan areas, 1980–2000
Authors: Johnston Ron , Poulsen Michael , Forrest James
Published: January 2003

The residential segregation of four main ethnic groups over the period 1980–2000 is examined for four US metropolitan areas, within the context of an assumed difference between so‐called ‘modern’ and ‘post‐modern’ cities. Using a newly developed measure of residential concentration, that binary distinction is found wanting: Los Angeles clearly differs from New York and Chicago, especially in the desegregation of African‐Americans over the two decades, but Miami is as close to those two ‘modern’ cities in its segregation patterns as it is to Los Angeles. Overall, the findings suggest little major change during the two decades: continued high levels of segregation of whites and African‐Americans (except in Los Angeles), alongside increased segregation of Hispanics, and slightly increased segregation of Asians. Copyright © 2003 John Wiley & Sons, Ltd.
Refugee dispersal in Denmark: from macro‐ to micro‐scale analysis
Authors: Wren Karen
Published: January 2003

Immigration and asylum has become a highly politicised policy area in Western Europe, where discourses resting on refugees as a ‘burden’ have prompted policy measures to disperse them. This paper examines the operation of refugee dispersal in Denmark using an integrated mixed‐method approach. Macro‐scale patterns are examined using statistical data, revealing that, at a national scale, the objectives of dispersal have been achieved, and refugees have been dispersed relatively evenly between regions, but at a regional scale, the reality has been different. In direct contradiction to the stated aims of the policy, dispersal has primarily been housing‐led, and has occurred mainly in areas of relative social deprivation. Dispersal has effectively constituted a process of socio‐spatial ethnic segregation. Micro‐scale processes are elucidated through the use of in‐depth interviews with a small number of refugees, which reveal significant isolation and social exclusion among dispersed refugees. There is also evidence that the policy, formulated within a culturally racist discourse in the public sphere, has also contributed to this discourse through the stigmatisation of refugees, a situation exacerbated by high levels of unemployment among the ethnic minorities generally. This paper therefore warns against the social engineering inherent within the conceptualisation of dispersal which, in effect, has resulted in the spatial segregation of refugees in areas experiencing pre‐existing deprivation and social exclusion, and the inherent dangers that this entails in fuelling resentment and anti‐refugee hostility. Copyright © 2003 John Wiley & Sons, Ltd.
Alternatives for measuring the unexplained wage gap
Authors: Toukoushian Robert K. , Hoffman Emily P.
Published: January 2003

This chapter examines the different options that are available to analysts for measuring pay disparaties, how they relate to one another, and their advantages and disadvantages.
Regression methods for correcting salary inequities between groups of academic employees
Authors: Oaxaca Ronald L. , Ransom Michael R.
Published: January 2003

This chapter explores some of the ways in which an institution can make salary adjustments to remove salary inequities for individuals. A new approach is developed for correcting salary inequities.
Critical analysis of potential body temperature confounders on neurochemical endpoints caused by direct dosing and maternal separation in neonatal mice: a study of bioallethrin and deltamethrin interactions with temperature on brain muscarinic receptors
Authors: Pauluhn Jürgen , Schmuck Gabriele
Published: January 2003

The present investigation was conducted to understand better possible confounding factors caused by direct dosing of neonatal mice during the pre‐weaning developmental period. By direct dosing, pups might encounter thermal challenges when temporarily removed from their ‘natural habitat’. Typically, this leads to a cold environment and food deprivation (impaired lactation) and modulation of the toxic potency of the substance administered. Growth retardation as a consequence of such behavioural changes in pups makes it increasingly difficult to differentiate specific from non‐specific mechanisms. Neonatal NMRI mice were dosed daily by gavage (0.7 mg kg−1 body wt.) from postnatal day (PND) 10–16 with S‐bioallethrin, deltamethrin or the vehicle. Then the pups, including their non‐treated foster dams, were subjected temporarily for 6 h day to a hypo‐, normo‐ or hyperthermic environment, which was followed by normal housing. The measured temperatures in the environmental chambers were ca. 21, 25 and 30°C, respectively. Thus, temperatures in the hypo‐ and normothermic groups are comparable to the temperatures commonly present in testing laboratories, whereas the hyperthermic condition is that temperature typically present in the ‘natural habitat’ of pups. A deviation from the normal behaviour of both pups and dams was observed in the hypo‐ and normothermic groups. In these groups the rectal temperatures of pups were markedly decreased, especially in the early phase of the study (PND 10–12). Neonates that received either test substance displayed changes in body weights and brain weights at terminal sacrifice (PND 17) when subjected temporarily to a non‐physiological environment. An enormous influence of environmental temperature on the density of muscarinic receptors in the crude synaptosomal fraction of the cerebral cortex was ascertained. In summary, these results demonstrate that the direct dosing of thermolabile neonatal mice by gavage is subject to significant artefacts that render the interpretation of findings from such studies difficult. It appears that if direct dosing of neonatal pups is mandated, and inhalation is a relevant route of exposure, the combined inhalation exposure of dams with their litters is an alternative procedure that does not cause disruption of the ‘natural habitat’ of pups. However, owing to their higher ventilation, under such conditions the pups may receive dosages at least double those of the dams. Copyright © 2003 John Wiley & Sons, Ltd.
Effect of single and binary combinations of plant‐derived molluscicides on different enzyme activities in the nervous tissue of Achatina fulica
Authors: Rao I. G. , Singh Amrita , Singh V. K. , Singh D. K.
Published: January 2003

Effect of single and binary treatments of plant‐derived molluscicides on different enzymes—acetylcholinesterase (AChE), lactic dehydrogenase (LDH) and acid/alkaline phosphatase (ACP/ALP)—in the nervous tissue of the harmful terrestrial snail Achatina fulica were studied. Sublethal in vivo 24‐h exposure to 40% and 80% LC50 of Azadirachta indica oil, Cedrus deodara oil, Allium sativum bulb powder, Nerium indicum bark powder and binary combinations of A. sativum (AS) + C. deodara (CD) and CD + A. indica (AI) oils significantly altered the activity of these enzymes in the nervous tissue of Achatina fulica. The binary treatment of AS + CD was more effective against AChE, LDH, and ALP than the single ones. However, binary treatment of AI + CD was more effective against ALP. Copyright © 2003 John Wiley & Sons, Ltd.
Metabolism of a tetraphenyltin compound in rats after a single oral dose
Authors: Ohhira Shuji , Matsui Hisao
Published: January 2003

The metabolism of tetraphenyltin in rat liver and kidney has been examined. Tetraphenyltin and its metabolites in the tissue were determined periodically for 96 h after a single oral dose of 55.4 mg kg−1 of tetraphenyltin by gas chromatography. The gas chromatographic method was able to determine simultaneously both inorganic tin and phenyltin compounds. Although initial (at 24 h) levels of tetraphenyltin in the liver approximated four times those in the kidneys, the levels of tetraphenyltin decreased more rapidly with time than those in the kidneys. These findings show that the tetraphenyltin accumulated more rapidly and highly in the liver, but was metabolized faster than that in the kidney. The levels of total tin in the liver 24 h after treatment were distinctly lower than those of di‐ or triphenyltin treatments in our previous studies and none of the animals showed characteristic symptoms. The toxic potencies of organotins generally correlate with accumulation of the chemicals. These results imply that the slight toxicities of tetraphenyltin might be due to the relatively low uptake of tin compounds after ingestion. The highest tin concentration among the metabolites of tetraphenyltin in the tissue, especially in liver, was observed as diphenyltin throughout the time period studied. These results suggest that part of the administered tetraphenyltin may cause some harmful effects as diphenyltin in rats, and this must be taken into consideration in toxicological research on tetraphenyltin. Copyright © 2003 John Wiley & Sons, Ltd.