bluuebunny/crossref_metadata_2025 huggingface dataset:
Kinetics and products of the reactions of selected diols with the OH radical
Authors: Bethel Heidi L. , Atkinson Roger , Arey Janet
Published: September 2002

Using a relative rate method, rate constants have been measured at 296 ± 2 K for the gas‐phase reactions of OH radicals with 1,2‐butanediol, 2,3‐butanediol, 1,3‐butanediol, and 2‐methyl‐2,4‐pentanediol, with rate constants (in units of 10−12 cm3 molecule−1 s−1) of 27.0 ± 5.6, 23.6 ± 6.3, 33.2 ± 6.8, and 27.7 ± 6.1, respectively, where the error limits include the estimated overall uncertainty of ±20% in the rate constant for the reference compound. Gas chromatographic analyses showed the formation of 1‐hydroxy‐2‐butanone from 1,2‐butanediol, 3‐hydroxy‐2‐butanone from 2,3‐butanediol, 1‐hydroxy‐3‐butanone from 1,3‐butanediol, and 4‐hydroxy‐4‐methyl‐2‐pentanone from 2‐methyl‐2,4‐pentanediol, with formation yields of 0.66 ± 0.11, 0.89 ± 0.09, 0.50 ± 0.09, and 0.47 ± 0.09, respectively, where the indicated errors are the estimated overall uncertainties. Pathways for the formation of these products are presented, together with a comparison of the measured and estimated rate constants and product yields. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 310–316, 2001
Raised and sunken bed technique for agroforestry on alkali soils of northwest India
Authors: Dagar J. C. , Sharma H. B. , Shukla Y. K.
Published: September 2002

Many forest tree and fruit species can be raised on highly alkali soil (pH > 10) but some of them such as pomegranate (Punica granatum) are unable to tolerate water stagnation. To avoid water stagnation problems during the monsoon the raised and sunken bed technique has been found suitable for agroforestry practices on highly alkali soil. One fruit‐yielding pomegranate and one oil‐yielding salvadora (Salvadora persica) plantation species were successfully grown on raised bunds to avoid water stagnation and rice–wheat and berseem–kallar grass rotation were grown on sunken‐beds constructed for the purpose. The experiment was initiated in 1996 and the above two crop rotations were followed for two consecutive years starting in the summer season. Results of these experiments have also shown that good growth of plantations, on an average 4·3 to 4·9 t ha−1 rice (salt tolerant var. CSR‐10) and 1·2 to 1·4 t ha−1 wheat (KRL 1–4), were obtained in sunken beds. In another rotation 21·3 to 36.8 t ha−1 fresh forage of kallar grass (Leptochloa fusca) and 44·9 to 47·8 t ha−1 fresh forage of berseem (Trifolium alexandrium) were obtained. After two years of the experiment, soil amelioration in terms of reduction in soil pH was significant. The effect of plantation in reducing soil pH showed that the pomegranate and salvadora both helped in reduction of soil pH, but the latter due to its well‐developed lateral root system was more efficient in lowering the soil pH even at lower depths. The reduction in soil pH by the berseem–kallar grass rotation was better than under rice–wheat rotation. Copyright © 2001 John Wiley & Sons, Ltd.
Mystery shopping: Using deception to measure service performance
Authors: Wilson Alan M.
Published: September 2002

This article reports on a program of exploratory research aimed at examining the practice of mystery shopping in service organizations. Mystery shopping, a form of participant observation, uses researchers to deceive customer service personnel into believing that they are serving real customers or potential customers. The research focused on the views of senior managers responsible for commissioning mystery shopping research and directors of market research agencies responsible for the provision of such research. The research findings identify the manner in which mystery shopping is used and the methods used to maximize the reliability of the technique. The study also revealed that employees' acceptance of this form of deception appears to be critical if the results are to be taken seriously by service personnel and if industrial relations within the organization are not to suffer. © 2001 John Wiley & Sons, Inc.
A stable calcium gradient near the plasma membrane
Authors: Braiman Alex , Gold'shtein Vladimir , Priel Zvi
Published: September 2002

The influx of calcium ions from extracellular space plays a central role in regulation of function of living cells. It has been hypothesized that calcium influx causes a rise in intracellular calcium concentration ([Ca2+]i) near the plasma membrane, thereby facilitating regulation of membrane associated processes without flooding the cell with Ca2+. Such a localization is extremely important, since high [Ca2+]i is toxic to cells. However, existence of sustained areas of different Ca2+ concentrations within a continuous aquatic medium is not a trivial phenomenon. The mathematical model presented here evaluates the cytosolic concentration of Ca2+ as a function of time and distance from the plasma membrane. The model has verified quantitatively the feasibility of a stable Ca2+ gradient in the cytosol with high values of Ca2+ concentration near the plasma membrane and evaluated its properties as a function of different cellular parameters. The formation of the gradient does not require special distribution of the intracellular contents, channels and pumps. However, it requires buffering of the cytosolic calcium by the intracellular stores and that the rate of calcium release from the stores near the plasma membrane be higher than in other parts of the cell. We suggest that this model can provide an adequate description of the elevated calcium plateau generally observed in electrically non‐excitable cells. Copyright © 2001 John Wiley & Sons, Ltd.
17O NMR studies on (E)‐3‐arylidenechromanone and ‐flavanone derivatives
Authors: Tóth Gábor , Simon András , Lévai Albert , Kählig Hanspeter , Kalchhauser Hermann
Published: September 2002

17O NMR data for some 3‐arylidenechromanones and ‐flavanones are discussed in terms of mesomeric and steric substituent interactions. The transmission of long‐range substituent effects was studied. 17O NMR chemical shifts were correlated with Hammett σp+ values for 4′‐substituted derivatives. Copyright © 2001 John Wiley & Sons, Ltd.
Structure and folding of glucagon‐like peptide‐1‐(7–36)‐amide in aqueous trifluoroethanol studied by NMR spectroscopy
Authors: Chang Xiaoqing , Keller Danielle , Bjørn Søren , Led Jens J.
Published: September 2002

The conformational changes of free, monomeric glucagon‐like peptide‐1‐(7–36)‐amide (GLP‐1) in aqueous solution with increasing concentrations of 2,2,2‐trifluoroethanol (TFE) were monitored by NMR spectroscopy. It was found that GLP‐1 gradually assumes a stable, single‐stranded helical structure in water solution when the TFE concentration is increased from 0 to 35% (v/v). No further structural changes were observed at higher TFE concentrations. The structure of GLP‐1 in 35% TFE was determined from 292 distance restraints and 44 angle restraints by distance geometry, simulating annealing and restrained energy minimization. The helical structure extends from T7 to K28, with a less well‐defined region around G16 and a disordered six‐residue N‐terminal domain. The folding process of GLP‐1 from random coil (in water) to helix (in 35% TFE) is initiated by the formation of the C‐terminal segment of the helix that is extended gradually towards the N‐terminus of the peptide with increasing concentration of TFE. The exchange rates of the slow exchanging amide protons indicate that the C‐terminal part of the helix is more stable than the N‐terminal part. Copyright © 2001 John Wiley & Sons, Ltd.
Ovarian expression of human insulin‐like growth factor‐I in transgenic mice results in cyst formation
Authors: Dyck Michael K. , Parlow A.F. , Sénéchal Jean‐François , Sirard Marc‐André , Pothier François
Published: September 2002

Insulin‐like growth factor‐I (IGF‐I) has been implicated in a wide variety of physiological processes including ovarian function. To better understand the ovarian role of IGF‐I, transgenic mice harbouring a human IGF‐I cDNA (hIGF‐I) under the control of the mouse LH receptor promoter were generated. Expression of the hIGF‐I, determined by Northern blot, was found to occur in the gonad tissues of these transgenic mice. The hIGF‐I protein was also detectable by radioimmunoassay in ovarian extracts as well as in the plasma. The fertility of mating transgenic females, as estimated by the number of implantation sites post‐coitum, did not appear to be affected. However, transgenic females who failed to mate and produce offspring were found to possess polycystic ovaries. Evaluation of testosterone, estradiol, and LH levels revealed that transgenic animals had significantly elevated circulating levels of testosterone compared to their non‐transgenic littermates, while LH levels in transgenic females were significantly lower. Yet, estradiol appeared to be unaffected. These results support the contention that the IGF system plays an important role in ovarian function and that an imbalance in this system may result in ovarian pathology. Mol. Reprod. Dev. 59:178–185, 2001. © 2001 Wiley‐Liss, Inc.
Simultaneous noninvasive measurement of CBF and CBV using double‐echo FAIR (DEFAIR)
Authors: Thomas David L. , Lythgoe Mark F. , Calamante Fernando , Gadian David G. , Ordidge Roger J.
Published: September 2002

A new method for measuring cerebral blood flow (CBF) and cerebral blood volume (CBV) noninvasively using MRI is presented. The approach is based on the technique of arterial spin labelling (ASL), in which CBF‐based contrast is generated by controlled modulation of the longitudinal magnetization of the blood. The proposed method also uses differences in T2 between tissue and blood to differentiate the two compartments and allow assessment of the relative size of each. Two successive EPI images are acquired following spin preparation using either a slice‐selective or global inversion pulse, and the technique is therefore referred to as double‐echo FAIR (DEFAIR). DEFAIR is demonstrated in the normal gerbil brain and during hypothermia, where reductions of both CBF and CBV are known to occur. It is also shown theoretically that this method can be extended to include a measurement of oxygen extraction fraction. The main drawbacks of the technique are the long acquisition time and relatively low sensitivity to hemodynamic changes compared to conventional qualitative T‐weighted BOLD contrast, which may limit its applicability and practical use in monitoring functional cerebral activation. However, the technique can be used repetitively in longer‐term time course studies due to its noninvasive and quantitative nature. Magn Reson Med 45:853–863, 2001. © 2001 Wiley‐Liss, Inc.
Cramér–Rao bounds: an evaluation tool for quantitation
Authors: Cavassila S. , Deval S. , Huegen C. , van Ormondt D. , Graveron‐Demilly D.
Published: September 2002

The Cramér–Rao lower bounds (CRBs) are the lowest possible standard deviations of all unbiased model parameter estimates obtained from the data. Consequently they give insight into the potential performance of quantitation estimators. Using analytical CRB expressions for spectral parameters of singlets and doublets in noise, one is able to judge the precision as a function of spectral and experimental parameters. We point out the usefulness of these expressions for experimental design. The influence of constraints (chemical prior knowledge) on spectral parameters of the peaks of doublets is demonstrated and the inherent benefits for quantitation are shown. Copyright­© 2001 John Wiley & Sons, Ltd.

Abbreviations used:

CRB

Cramér‐Rao lower bounds
N‐cadherin is regulated by gonadal steroids in adult sexually dimorphic spinal motoneurons
Authors: Monks Douglas A. , Getsios Spiro , MacCalman Colin D. , Watson Neil V.
Published: September 2002

Gonadal steroids influence the morphology and function of neurons in the adult spinal cord through cellular and molecular mechanisms that are largely unknown. The cadherins are cell adhesion molecules that participate in the formation and organization of the CNS during embryonic development, and recent evidence suggests that the cadherins continue to regulate neural structure and function in adulthood. Using degenerate oligonucleotides coding conserved regions of the catenin‐binding domain of classical cadherins in a RT‐PCR cloning strategy, we identified several cadherin subtypes, the most frequently cloned being N‐, E‐, and R‐cadherin, suggesting that these are the major classical cadherin subtypes present in the adult male rat lumbosacral spinal cord. We then examined cadherin expression levels of these cadherin subtypes under steroid conditions known to induce plastic changes in spinal motoneurons. Semiquantitative PCR revealed that mRNA levels of N‐cadherin, but not E‐cadherin or R‐cadherin, are elevated in castrated rats treated with testosterone, 17β‐estradiol, or dihydrotestosterone relative to castrate rats not treated with steroids. Immunolocalization of N‐cadherin revealed that steroid treatment increased N‐cadherin expression levels in functionally related neural populations whose morphology and function are regulated by steroids. These results suggest a role for N‐cadherin in steroid‐induced neuroplastic change in the adult lumbar spinal cord. © 2001 John Wiley & Sons, Inc. J Neurobiol 47: 255–264, 2001
Solving dynamic macroeconomic policy games using the algorithm OPTGAME 1.0
Authors: Hager Manfred , Neck Reinhard , Behrens Doris A.
Published: September 2002

In this paper we briefly summarise the OPTGAME 1.0 algorithm, which has been developed to determine equilibrium solutions of dynamic games in discrete time. It can be applied to obtain approximate numerical solutions for two‐player difference games where the objective functions are quadratic and the dynamic system is non‐linear. The non‐linear system equations are linearized numerically, substituting a linear time‐varying system for the non‐linear time‐invariant system. OPTGAME 1.0 delivers open‐loop and feedback Nash equilibrium solutions, open‐loop and feedback Stackelberg equilibrium solutions, and Pareto‐optimal solutions. The algorithm has been implemented in the statistical programming system GAUSS. We report about tentative applications of OPTGAME 1.0 to a small macroeconometric model for Austria, AUSTRIA1, to show the feasibility of the calculations and to give examples of how to interpret their results. Copyright © 2001 John Wiley & Sons, Ltd.
Outsourcing in the public services: a comparative analysis of practice, capability and impact
Authors: Kakabadse Andrew , Kakabadse Nada
Published: September 2002

This article analyses thinking and practice concerning privatization and outsourcing in the public services and compares recent trends with the findings of an extensive comparative survey of outsourcing conducted at Cranfield School of Management. Particular attention is paid to the systems and processes being outsourced, their importance to the organization and the impact of outsourcing on public service organizations. The results of the survey suggest that public service managers are more skilful than managers from the private sector at handling the transactional aspects of outsourcing. However, managers from public service organizations, unlike managers from the private sector, assert that outsourcing is damaging the running of public service enterprises. It is concluded that until the political and administrative processes are more closely aligned public service managers will continue to hold a more negative view of outsourcing. Copyright © 2001 John Wiley & Sons, Ltd.
The Impact of Mandatory Waiting Periods and Parental Consent Laws on the Timing of Abortion and State of Occurrence among Adolescents in Mississippi and South Carolina
Authors: Joyce Ted , Kaestner Robert
Published: September 2002

Individual data on induced abortions from Mississippi and South Carolina are used to examine the effect of parental consent laws and mandatory delay statutes on two outcomes among teens: the point in pregnancy at which the abortion occurs and whether teens obtain abortions in or outside their state of residence. No effect of either law was found on the timing and location of abortion among minors relative to older teens in South Carolina. In Mississippi, however, both laws are associated with an increase in the proportion of abortions performed out of the state and the parental consent statute with later abortions. The conclusion is that Mississippi's 24‐hour as compared with South Carolina's one‐hour delay requirement, and Mississippi's two‐parent as contrasted with South Carolina's one‐parent consent statute explain the stronger behavioral response in Mississippi. © 2001 by the Association for Public Policy Management and Ananlysis.
Terpolymerization monitoring with ATR‐FTIR spectroscopy
Authors: Hua Hong , Dubé Marc A.
Published: September 2002

Butyl acrylate, methyl methacrylate, and vinyl acetate solution and emulsion terpolymerizations were conducted. Attenuated total relflection‐Fourier transform infrared spectroscopy equipped with conduit and diamond‐composite sensor technology was used to monitor solution terpolymerizations off‐line and emulsion terpolymerizations in‐line. Monomer conversion and terpolymer composition changes as a function of time were calculated by monitoring the peak height of characteristic absorbances of each monomer. Results obtained from the ReactIR™ 1000 reaction‐analysis system agreed well with those determined by traditional gravimetry and 1H NMR spectroscopy. For the solution terpolymerizations, improved models developed previously to incorporate solvent effects on solution polymerizations of butyl acrylate and vinyl acetate monomers were applied to predict monomer conversion, copolymer composition, and molecular weight averages. Comparisons between experimental data and model predictions are presented. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1860–1876, 2001
Anomalous thermochromic transition of poly(di‐n‐octylsilane)
Authors: Kanai Toshinobu , Ishibashi. Hiroki , Hayashi Yoshikazu , Oka Kunio , Dohmaru Takaaki , Ogawa Tatsuo , Furukawa Shoji , West Robert
Published: September 2002

The thermochromic behavior of poly(di‐n‐octylsilane) {[Si(C8H17)2]n; PDOS} was studied by ultraviolet (UV) absorption, differential scanning calorimetry, and X‐ray diffraction measurements. The structure of PDOS in the low‐temperature phase strongly depended on not only the temperature but also the rate of cooling, that is, the thermal history. Temperature‐dependent UV absorption spectra were highly dependent on thermal hysteresis. Cooled rapidly (10 K/min), PDOS showed two absorption peaks at 3.32 and 3.51 eV in low‐temperature‐ordered phases, whereas a single absorption peak at 3.32 eV became predominant with slow cooling (0.3 K/min). The appearance of the two peaks at low temperatures suggested that a mixture of different conformations was introduced by rapid cooling. A fiber diffraction pattern measured at 240 K after rapid cooling also showed evidence of the existence of novel conformation. A temperature‐dependent powder X‐ray diffraction pattern changed significantly between 270 and 280 K. Rapid cooling reduced the intensity of the X‐ray diffraction peak in this temperature region. This intensity change was explained by the conformational mixture in the polymer. © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 1085–1092, 2001
Proteomic analysis of normal and malignant prostate tissue to identify novel proteins lost in cancer
Authors: Meehan Katie L. , Holland John W. , Dawkins Hugh J.S.
Published: September 2002

BACKGROUND

Alterations of important protein pathways, including loss of prostate secretory granules, and disruption of the prostatic secretory pathway have been identified as early events in malignancy. In this study, proteomics was used to map the differences in protein expression between normal and malignant prostate tissues and to identify and analyze differentially expressed proteins in human prostate tissue with particular regard to the proteins lost in malignancy.

METHODS

Small quantities of normal and malignant prostate tissue were taken fresh from 34 radical prostatectomy cases. After histological examination, proteins were solubilized from selected tissues and separated using two‐dimensional electrophoresis. Using image analysis, the proteome of normal and malignant tissues were mapped and differentially expressed proteins (present in normal and absent in malignant tissue) were identified and subsequently analyzed using peptide mass finger printing and N‐terminal sequencing. Western blotting and immunohistochemistry were performed to examine expression profiles and tissue localization of candidate proteins.

RESULTS

Comparison of protein maps of normal and malignant prostate were used to identify 20 proteins which were lost in malignant transformation, including prostate specific antigen (PSA), alpha‐1 antichymotrypsin (ACT), haptoglobin, and lactoylglutathione lyase. Three of the 20 had not previously been reported in human prostate tissue (Ubiquitin‐like NEDD8, calponin, and a follistatin‐related protein). Western blotting confirmed differences in the expression profiles of NEDD8 and calponin, and immunohistochemistry demonstrated differences in the cellular localization of these two proteins in normal and malignant prostate glands.

CONCLUSIONS

The expression of NEDD8, calponin, and the follistatin‐related protein in normal prostate tissues is a novel finding and the role of these important functional proteins in normal prostate and their loss or reduced expression in prostate malignancy warrants further investigations. Prostate 50: 54–63, 2002. © 2002 Wiley‐Liss, Inc.
Characterization of mutations in the two‐component histidine kinase gene that confer fludioxonil resistance and osmotic sensitivity in the os‐1 mutants of Neurospora crassa
Authors: Ochiai Noriyuki , Fujimura Makoto , Motoyama Takayuki , Ichiishi Akihiko , Usami Ron , Horikoshi Koki , Yamaguchi Isamu
Published: September 2002

Osmotic‐sensitive (os‐1) mutant alleles in Neurospora crassa exhibit resistance to dicarboximides, aromatic hydrocarbons and phenylpyrroles. We have previously reported that the os‐1 mutants can be classified into two groups based on their resistance to fungicides and osmotic stress: type I, which are highly resistant to iprodione and fludioxonil but moderately sensitive to osmotic stress, and type II, which are highly sensitive to osmotic stress but moderately resistant to fungicides. To explain the mechanism of resistance to these fungicides, we cloned and sequenced the mutant os‐1 genes that encode putative osmo‐sensing histidine kinase. Within the os‐1 gene product (Os1p), the type I strains, NM233t and Y256M209, carried a stop codon at amino acid position 308 and a frameshift at amino acid position 294, respectively. These mutation sites were located on the upstream of histidine kinase and the response regulator domains of Os1p, strongly suggesting that type I strains are null mutants. The null mutants, NM233t and Y256M209, were highly resistant to iprodione and fludioxonil; thus Os1p is essential for these fungicides to express their antifungal activity. The amino acid changes in Os1p, 625Pro from Leu, 578Val from Ala, and 580Arg from Gly were found in the type II strains, M16, M155‐1 and P5990, respectively. Os1p is novel in having six tandem repeats of 90 amino acids in the N terminal. Each amino acid change of the type II strains was located on the fifth unit of six tandem repeats. Type II strains with single amino acid changes were more sensitive to osmotic stress than the null mutants (type I), indicating that the amino acid repeats of Os1p were responsible for an important function in osmo‐regulation.

© 2001 Society of Chemical Industry
The ABC transporter BcatrB from Botrytis cinerea is a determinant of the activity of the phenylpyrrole fungicide fludioxonil
Authors: Vermeulen T , Schoonbeek H , De Waard Maarten A
Published: September 2002

This study demonstrates that the ATP‐binding cassette (ABC) transporter BcatrB from Botrytis cinerea influences the activity of phenylpyrrole fungicides against the pathogen. This conclusion is based on toxicity assays and northern analysis experiments which show that BcatrB replacement mutants, which do not express the BcatrB gene, show an increased sensitivity to the phenylpyrrole fungicides fludioxonil and fenpiclonil. Mutants overexpressing BcatrB exhibit a decreased sensitivity to these fungicides. In addition, accumulation of fludioxonil by BcatrB replacement mutants was higher than by wild‐type isolates. For mutants overexpressing BcatrB the reverse was observed. Additional ABC and major facilitator superfamily (MFS) transporter genes were identified in an expressed sequence tag (EST) database, suggesting that B cinerea has gene families of ABC and MFS transporters. Corresponding fragments of ten ABC (BcatrC–BcatrN) and three MFS transporter genes (Bcmfs1–4) were cloned and characterised. Fludioxonil affected the transcript level of some members of these gene families in germlings during a short treatment with the fungicide at sub‐lethal concentrations. Hence, other ABC and MFS transporters may affect the activity of phenylpyrrole fungicides as well. Other fungicides such as the anilinopyrimidine fungicide cyprodinil, the azole fungicide tebuconazole, the dicarboximide fungicide iprodione and the strobilurin fungicide trifloxystrobin also induced transcription of some of the ABC and MFS transporter genes identified. Therefore, we propose that various ABC and MFS transporters function in protection of the fungus against fungicides and are involved in multi‐drug resistance development.

© 2001 Society of Chemical Industry
Leaf surfaces and the bioavailability of pesticide residues
Authors: Chowdhury A B M Nasir U , Jepson Paul C , Howse Philip E , Ford Martyn G
Published: September 2002

Laboratory bioassays were carried out to determine the toxicity to Folsomia candida Willem (Collembola: Isotomidae) of residues of a pyrethroid insecticide, deltamethrin, and an organophosphorus insecticide, dimethoate, on different leaf surfaces. The test leaves included a range of species and leaves of different ages. Dose‐response relationships were estimated for F candida walking over the various treated leaf substrates. Probit analysis was used to estimate the means and standard deviations of the associated tolerance distributions expressed as g AI ha−1. Parallelism tests were undertaken to compare the susceptibilities of F candida to the two compounds applied to the different leaf surfaces. On deltamethrin‐treated leaf surfaces, the LD50 values for F candida varied from 6.36 to 77.14 g AI ha−1. F candida was least susceptible to deltamethrin residues when applied to leaves of dwarf bean (Phaseolus vulgarus L) and the highest susceptibility was observed following application to leaves of seedlings of barley (Hordeum vulgare L). In contrast, the LD50 values observed for dimethoate treatments did not differ significantly between leaf types, ranging from 1.35 to 8.69 g AI ha−1. The laboratory data on susceptibility of F candida on different leaf types for different pesticides can be used to investigate the role of leaf surface properties in modifying the toxicity of applied pesticides to exposed invertebrates.

© 2001 Society of Chemical Industry
Performance‐based engineering concepts for unreinforced masonry building structures
Authors: Abrams Daniel P
Published: September 2002

Performance‐based concepts are discussed in terms of their application for seismic assessment, rehabilitation and design of unreinforced masonry buildings. Deviations from traditional design approaches for masonry are discussed in terms of new performance‐based engineering procedures recently introduced through the FEMA 273 Guidelines for Seismic Rehabilitation. Difficulties in characterizing performance states for unreinforced masonry structural systems are discussed to present the challenge of implementing performance‐based approaches for masonry buildings. Four analytical methods are described for estimating seismic demand on individual wall or pier components, based on linear or nonlinear behaviour and static or dynamic response. Expressions to estimate lateral strength of unreinforced masonry wall and pier components are given. Acceptable performance limits for masonry walls and piers are presented for components behaving in rocking, bed joint sliding, toe compression or diagonal tension. Future directions for performance‐based engineering of unreinforced masonry buildings are discussed as well as research needed for further development of these concepts.
Theoretical and computational aspects of extended wave functions
Authors: Carbó‐Dorca R. , Karwowski J.
Published: September 2002

Relations between the extended wave functions defined by Carbó‐Dorca in connection with studies on quantum similarity problems and the wave functions of Schrödinger, Lévy‐Leblond, and Dirac equations are investigated. In particular, it is pointed out that solutions of the Lévy‐Leblond equation are equal to the appropriate extensions of the corresponding Schrödinger wave functions. The quantum mechanical continuity equation is applied to analyze the physical meaning of the extended wave functions. Finally, usefulness of the concept of the extended wave function in designing relativistic variational calculations in kinetically balanced basis sets is briefly discussed. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem 84: 331–337, 2001
Generalized spin orbital calculations of spin‐frustrated molecules
Authors: Yamaki D. , Shigeta Y. , Yamanaka S. , Nagao H. , Yamaguchi K.
Published: September 2002

It is difficult to consider the closed chain which contains odd‐number spin sites under the UHF approximation because of the spin frustration. The generalized HF (GHF) method, which deals with generalized spin orbitals (GSO) of the form ϕαα+ϕββ, can provide a characteristic electronic state with noncollinear spin configuration. In this article, explicit expressions of effective exchange integrals ( Jab values) based on GHF solutions were derived for the closed chain which contains odd‐number spin sites. The Jab values were calculated for simple systems such as equilateral triangular H3, equilateral pentagonal H5, and so on. Furthermore, spin correlations and electron correlations of the H3 molecule are discussed by using visualization methods for electron correlations. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Metal ion adducts in the structural analysis of ginsenosides by electrospray ionization with multi‐stage mass spectrometry
Authors: Cui Meng , Song Fengrui , Liu Zhiqiang , Liu Shuying
Published: September 2002

The effect of metal (Li+, Na+, K+, Ag+) cationization on collision‐induced dissociation of ginsenosides was investigated by electrospray ionization mass spectrometry combined with multi‐stage mass spectrometry (ESI‐MSn). The fragments of sodiated and lithiated molecules give valuable structural information regarding the nature of the aglycone and the sequence and linkage information of sugar moieties. However, the number and relative abundances of fragment ions from lithiated ginsenosides are significantly greater than for the sodiated species. The K+ adducts undergo glycosidic cleavages and very limited cross‐ring reactions. The silver ion adducts fragment mainly through glycosidic cleavages. Copyright © 2001 John Wiley & Sons, Ltd.
Investigation of hexabromocyclododecane thermal degradation pathways by gas chromatography/mass spectrometry
Authors: Barontini Federica , Cozzani Valerio , Cuzzola Angela , Petarca Luigi
Published: September 2002

The decomposition products of hexabromocyclododecane (HBCD), a widely used brominated flame retardant, were investigated by gas chromatography/mass spectrometry (GC/MS). HBCD thermal degradation was conducted under a moderate heating rate (10 °C/min) in a batch reactor using both inert and oxidizing atmospheres. GC/MS analysis allowed the identification of substances derived from the primary pyrolysis process at the moderate heating rates used. The presence of oxygen seems to have a negligible influence on the degradation products obtained in HBCD decomposition, at least at moderate heating rates. Based on the identified products, the main pathways of HBCD thermal degradation were assessed and a mechanism for HBCD decomposition was proposed. The results obtained indicate that hexa‐, penta‐ and tetrabrominated polyaromatic structures seem not to be primary products of HBCD decomposition, and may only be obtained by secondary bromination reactions. Copyright © 2001 John Wiley & Sons, Ltd.
Study on high‐solid polyester‐based polyurethane/tinned iron interface
Authors: Wu Limin , Chen Xichong , Hu Dongzhi , Zou Lijun
Published: September 2002

High‐solid polyester polyol resins (low molecular weight) were synthesized and cured by isophorone diisocyanate on tinned iron panels at different temperatures for different times. The resins and polyurethane films were studied by gel permeation chromatography (GPC) and dynamic mechanical analysis (DMA). The polyurethane/tinned iron interfaces were investigated by atomic force microscopy (AFM), the peel test and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS). The results showed that the polyurethane obtained from a high‐solid resin had higher interfacial roughness and adhesion strength than those from a relatively low‐solid resin. As the curing temperature increased, adhesion strength and the interfacial roughness increased and polyurethane interfacial images changed from rough morphology when cured at room temperature to random hole morphology when cured at 100 °C. The ToF‐SIMS microanalysis showed that no polymeric or metallic groups or segments existed on either the metallic or the polyurethane side. Copyright © 2001 John Wiley & Sons, Ltd.
Quantification of PVC–PMMA polymer blend compositions by XPS in the presence of x‐ray degradation effects
Authors: Artyushkova K. , Fulghum J. E.
Published: September 2002

X‐ray photoelectron spectroscopy is widely used for the quantitative surface analysis of polymer blends. The compositions of some polymers can change under x‐ray exposure, influencing peak intensities and positions in survey spectra and, in addition, the peak shapes in high‐energy resolution spectra. In order to quantify spectra acquired after prolonged (>15 min) x‐ray exposure, polymer decomposition may need to be taken into account. Calculating the surface composition of a polymer blend using survey and high‐resolution core‐level spectra is thus not always straightforward.

Halogenated compounds, especially chlorinated, are known to degrade with x‐ray exposure, resulting in a decrease in the Cl 2p photopeak intensity and an increase in C 1s intensity. In this work, 50 : 50 PVC–PMMA blends are used to evaluate quantitative methods that correct for PVC degradation, based upon either survey or high‐resolution spectra. For survey quantification, degradation data were acquired from both blends and pure polymers in order to measure the rate of change of the photoelectron signal intensity. Correction factors were developed based on changes in C 1s, O 1s and Cl 2p intensities as a function of analysis time. High‐resolution C 1s spectra were curve‐fit using photopeak shapes acquired from PVC and PMMA standards. After degradation, an additional peak attributed to hydrocarbon (HC), which is the product of PVC dehydrochlorination, is required in the curve‐fit. Non‐uniform HC contamination present initially in some of the PVC–PMMA blends complicates the quantification. The determination of PVC and PMMA concentrations based upon different approaches to the C 1s curve‐fitting is presented.

The influence of PVC degradation on image appearance and analysis has also been investigated. Principal component analysis (PCA) and classification methods are used to extract maps of the pure components from a degradation image data set. The maps are compared with elemental XPS images and maps of the pure components extracted from an images‐to‐spectra data set. Analysis of the image data provides insight into the difficulties in basing quantification on the C 1s photopeak curve‐fits. Copyright © 2001 John Wiley & Sons, Ltd.
The choice of entry mode in sequential foreign direct investment
Authors: Chang Sea‐Jin , Rosenzweig Philip M.
Published: September 2002

Relatively few studies have examined the importance of an entry's sequential position to the choice of foreign entry mode. We use a dynamic model to analyze sequential entries into the United States from 1975 to 1992. Our findings show that several independent variables which explain a firm's initial mode of entry do not explain the modes of subsequent entries. These findings underscore the importance of experience in foreign investment, as companies learn from early entries and adapt the modes of subsequent ones. Copyright © 2001 John Wiley & Sons, Ltd.
Review of oleoresin capsicum (pepper) sprays for self‐defense against captive wildlife
Authors: Miller David S.
Published: September 2002

Pepper (oleoresin capsicum) sprays appear to be a “less‐than‐lethal” option for repelling attacks by captive wildlife. These products may also deter wildlife from approaching, before an attack occurs. Such products should only be used when human life or severe injury is at stake. These products work by causing irritation of the ocular and respiratory membranes that distracts or debilitates the attacker. In humans, inflammation of the mucous membranes that restricts respiration and causes eyelid swelling, along with variable responses to pain, can debilitate aggressive people long enough to allow escape or application of restraint. However, some highly motivated animals may not be sufficiently incapacitated by the physiological effects of pepper spray on mucous membranes, and may also be able to override any sensations of pain. In the United States, the Environmental Protection Agency has registered pepper spray products that appear to be effective against dogs and bears. However, little data are available to justify the registration of some products. It is important to consider effective spray distance, spray pattern, duration of spray, quantity of content, canister size, and safety features when selecting a product. A training program and policies for the use of pepper sprays should be in place before providing the product to staff. Safety and decontamination protocols need to be included as a part of training procedures. Local law enforcement agencies may be able to assist with training programs and for addressing liability issues. Zoo Biol 20:389–398, 2001. © 2001 Wiley‐Liss, Inc.
Effects of intrathecal morphine, baclofen, clonidine and R‐PIA on the acute allodynia‐like behaviours after spinal cord ischaemia in rats
Authors: Von Heijne Margareta , Hao Jing‐Xia , Sollevi Alf , Xu Xiao‐Jun
Published: September 2002

The present study assessed the efficacy and potency of intrathecal (i.t.) administration of the opiate morphine, the γ‐aminobutyric acid‐B (GABAB) receptor agonist baclofen, the α2‐adrenoceptor agonist clonidine and the adenosine A1‐receptor agonist R‐phenylisopropyl‐adenosine (R‐PIA) on the acute allodynia‐like behaviour after photochemically induced spinal cord injury (SCI) in rats. Rats displaying allodynia‐like behaviours to brushing, von Frey hairs and cold stimulation 1–2 days after photochemically induced SCI were studied. In a cumulative dose regime, morphine (0.1–10 μ g), baclofen (0.1–1 μ g), clonidine (0.1–10 μ g) and R‐PIA (0.01–10 nmol) were administered i.t. through an implanted catheter at the lumbar spinal cord. All tested drugs dose‐dependently reduced the brushing, von Frey hairs and cold stimulation‐induced allodynia‐like behaviour. No increase in adverse effects such as motor deficits was found for morphine, clonidine and R‐PIA. There was a slight increase in motor impairments at the highest dose of baclofen. For the mechanical allodynia, morphine appeared to be most effective, whereas baclofen, clonidine and R‐PIA only provided a partial alleviation. For the cold allodynia, morphine and baclofen were more effective than clonidine and R‐PIA. In relieving acute mechanical and cold allodynia‐like behaviours in rats 1–2 days after SCI, i.t. morphine and baclofen were superior to clonidine and R‐PIA.
RINGS: a new search/match database for identification by polycrystalline electron diffraction
Authors: Denley David R. , Hart Haskell V.
Published: September 2002

RINGS is a relational database built from NIST Crystal Data for the identification of polycrystalline solids by selected area electron diffraction (SAED) and elemental analysis using MicrosoftAccess 97(subsequently converted toAccess 2000). Experimentaldspacings are matched against values calculated from reduced unit cells, thereby fully and rigorously incorporating the effects of double diffraction. A total of 79136 inorganic phases are included with original Crystal Data reference codes, allowing access to all the information in NIST Crystal Data. Specific examples illustrate the advantages over previous approaches to the problem. This database will be most useful to researchers in mineralogy, metallurgy, materials science, forensics and analytical chemistry who seek to identify well characterized phases with known unit cells.
A standardless X-ray diffraction method for the quantitative analysis of multiphase mixtures. II. Application to non-infinitely thick samples
Authors: Gomez Eva T. , Sanfeliu Teófilo , Rius Jordi
Published: September 2002

In 1987, Rius, Plana & Palanques [J. Appl. Cryst.(1987),20, 457–460] devised an X-ray powder diffraction method based on the `least-squares' determination of calibration constants using only the diffracted intensities and the calculated absorption coefficients of the components. This method was developed for `infinitely thick' samples, a condition which is seldom met by airborne particulates because of the small amount of material normally available. Since the analysis of such samples may become one of the principal applications of the method, this condition represents a serious limitation. The simplest way to overcome this limitation is by correcting the measured intensities. This can be done either by direct measurement of the sample transmission, or alternatively, by using refined transmission values. In the latter case no experimental values are necessary. With the help of some test calculations, the viability of both possibilities has been explored.
Structural and anisotropic thermal expansion correlation of Li2ZrO3at different temperatures
Authors: Heiba Z. K. , El-Sayed Karimat
Published: September 2002

Structural and thermal expansion studies of Li2ZrO3were carried out by recording X-ray powder diffraction patterns at five temperatures, 82, 198, 300, 423 and 573 K. The Rietveld refinement method was used for the analysis. There were large anisotropic changes in the lattice parameters as a function of temperature, slight changes in the fractional coordinates of the different atoms, and anisotropic changes in the interatomic distances between the different cations. The correlation of these anisotropies with the structure is considered.
X-ray beam steering with flexible polycapillaries
Authors: Arndt U. W. , Scotcher S. W.
Published: September 2002

X-ray beams from a fine-focus X-ray tube can be displaced by appreciable amounts without a serious intensity loss by passing these beams through a glass capillary or polycapillary, the tip of which is translated mechanically under fine control.
A user‐centred approach to e‐book design
Authors: Wilson Ruth , Landoni Monica , Gibb Forbes
Published: September 2002

This paper considers the Electronic Books ON‐screen Interface (EBONI) Project’s research into the importance of the user when designing electronic textbooks. The results of the Visual Book and the WEB Book experiments, which explored design aspects of e‐books and provide a backdrop to EBONI’s research, are presented. EBONI’s methodology and evaluations, involving over 200 students, lecturers and researchers in UK Higher Education, are described, and the findings discussed. It is proposed that, while aspects of paper books such as tables of contents, indexes and typography should be retained, books delivered electronically should also adapt to fit the new medium through use of hypertext, search engines and multimedia. In terms of the design of e‐book hardware, issues such as size and weight, display technology and functionality are of primary importance to users. These findings have been presented to creators of educational digital content in the form of a set of Electronic Textbook Design Guidelines.
Developing supply chain strategies based on the survey of supply chain quality and technology management
Authors: Kuei Chu‐Hua , Madu Christian N. , Lin Chinho , Chow Wing S.
Published: September 2002

A two‐stage framework is developed on supply chain quality and technology management. This is based on a survey of the perceptions of practicing managers from Hong Kong’s business corporations. The two‐stage process involves empirical assessment of strategic supply chain quality and technology variables, and then using quality function deployment to deploy them to improve the competitiveness of the supply chain. This will help to achieve synergy among suppliers by focusing on the critical strategic variables to achieve sustainable competitiveness.
Changes in Titin Isoform Expression in Pacing-Induced Cardiac Failure Give Rise to Increased Passive Muscle Stiffness
Authors: Wu Yiming , Bell Stephen P. , Trombitas Karoly , Witt Christian C. , Labeit Siegfried , LeWinter Martin M. , Granzier Henk
Published: September 2002

Background—

Titin contains a molecular spring segment that underlies passive myocardial stiffness. Myocardium coexpresses titin isoforms with molecular spring length variants and, consequently, distinct stiffness characteristics: the stiff N2B isoform (short spring) and more compliant N2BA isoform (long spring). We tested whether changes in titin isoform expression occur in the diastolic dysfunction that accompanies heart failure.

Methods and Results—

We used the tachycardia-induced dilated cardiomyopathy canine model (4-week pacing) and found that control myocardium coexpresses the N2B and N2BA isoforms at similar levels, whereas in dilated cardiomyopathy the expression ratio had shifted, without affecting the amount of total titin, toward more prominent N2B expression. This shift was accompanied by elevated titin-based passive muscle stiffness. Pacing also resulted in significant upregulation of obscurin, an ≈800-kDa elastic protein with several signaling domains.

Conclusions—

Coexpression of titin isoforms with distinct mechanical properties allows modulation of passive stiffness via adjustment of the isoform expression ratio. The canine pacing-induced heart failure model uses this mechanism to increase myocardial stiffness. Thus, changes in titin isoform expression may play a role in diastolic dysfunction in heart failure.
Synthesis, Separation and Characterization of Naphthobenzo-condensed Porphyrazinato Nickel(II) Complexes
Authors: POLLEY RAINER , LINßEN TORSTEN GOLO , STIHLER PATRICK , HANACK MICHAEL
Published: September 2002

Phthalocyanines and 2,3-naphthalocyanines are macrocyclic compounds which possess a variety of properties of potential importance in advanced technologies. The article discusses the influence of successive condensation of additional benzene rings to the phthalocyanine system. For this purpose three hexyloxy- and heptyl-substituted 2,3-dicyanonaphthalenes 3,7,11 and the respective 2,3-naphthalocyaninato nickel(II) complexes were prepared. In three statistical condensations of tetraphenylphthalodinitrile ( TPPN ) (12) and 2,3-dicyanonaphthalenes, 3,7,11, twelve unsymmetrical naphthobenzo-condensed porphyrazinato nickel(II) complexes 13b-15e were synthesized and separated by common column chromatography. All complexes were characterized by mass spectrometry, IR, UV and 1 H NMR spectroscopy.