bluuebunny/crossref_metadata_2025 huggingface dataset:
Fooling the eye of the beholder: deceptive status signalling among the poor in developing countries
Authors: Van Kempen Luuk
Published: March 2003

Poor consumers in the developing world use a variety of status signalling devices that rely on deception of the observer. A frequently used deceptive strategy is the consumption of counterfeit instead of original status‐intensive goods, mainly cheap copies of expensive brand‐name goods from developed countries. The choice for such deceptive modes of conspicuous consumption is analysed within a product characteristics approach as developed by Lancaster and compared with non‐deceptive alternatives. Under the controversial assumption that the poor care about status, it is shown that counterfeit goods embody a more ‘appropriate’ combination of status and functionality than original goods. It appears that the consumption of counterfeits potentially enhances the welfare of low‐income consumers, depending on the extent to which the eye of the relevant beholder is effectively deceived. Copyright © 2003 John Wiley & Sons, Ltd.
NGOs' role in limiting national sovereignty over environmental resources of global significance: the 1990 campaign against the Southern Okavango Integrated Water Development Project
Authors: Thomas Alan
Published: March 2003

This paper analyses the NGO campaign against the proposed development of the Okavango Delta in 1990, and the subsequent policy change by the Botswana government. Four explanatory factors are explored: the democratic attributes of the domestic political context; the internationalisation of the issue; the complementary role of different NGOs; and the relative lack of impact on major economic stakeholders. The limitations of the campaign are noted in relation to more recent developments.

We conclude that confrontation and collaboration can complement each other. Framing environmental issues as international, mobilising communities and facilitating participation, and providing independent technical expertise, are all important NGO activities. However, whereas in 1990 these were carried out in opposition to government, nowadays they are likely to be undertaken in a co‐operative framework of international agreements. NGOs may thereby gain more political space, but be in danger of co‐option. Copyright © 2003 John Wiley & Sons, Ltd.
Observations on the histochemistry and ultrastructure of regenerating caudal epidermis of the tuatara Sphenodon punctatus (Sphenodontida, Lepidosauria, Reptilia)
Authors: Alibardi Lorenzo , Maderson Paul F.A.
Published: March 2003

Study of the histology, histochemistry, and fine structure of caudal epidermal regeneration in Sphenodon punctatus through restoration of a scaled form reveals that the processes involved resemble those known in lizards. Following establishment of a wound epithelium (WE), subjacent scale neogenesis involves epidermal downgrowths into the dermis. Although the process is extremely slow, and most new scales do not overlap, their epidermal coverings reestablish epidermal generation (EG) formation. As in lizards, the flat, α‐keratogenic, WE cells contain lipids as revealed by their affinity for Sudan III. A few mucous cells that store large PAS‐positive mucus‐like granules also occur in WE. During differentiation of WE cells, among the bundles of 70‐nm tonofilaments are many lamellar bodies (LBs) and mucous granules (MGs) that discharge their contents into the cytoplasm and extracellular spaces producing a strongly PAS‐positive keratinized tissue. Richness of epidermal lipids coexistent with mucus is a primitive characteristic for amniote vertebrates, probably related to functions as a barrier to cutaneous water loss (CWL). As scale neogenesis begins, beneath the superficial WE appear 3–5 layers of irregularly shaped cells. These contain tonofilament bundles surrounded by small, round keratohyalin‐like granules (KHLGs) and a keratinized matrix with β‐keratin packets and a 3–5‐nm thick keratin granulation. This mixture of α‐ and β‐keratogenic capacities resembles that seen in the innermost cells of a normal tuatara epidermal generation. As in the latter, but in contrast to both normal and regenerating lizard epidermis, no definable shedding complex with interdigitating clear layer and oberhautchen cells occurs (Alibardi and Maderson, 2003). The tortuous boundaries, and merging β‐keratin packets, identify subjacent keratinizing cells as precursors of the typical stratified, squamous β‐layer seen in long‐term regenerated caudal skin wherein the entire vertical sequence of epidermal layers resembles that of normal scales. The sequence of events in caudal epidermal regeneration in S. punctatus resembles that documented for lizards. Observed differences between posttrauma scale neogenesis and scale embryogenesis are responses to functional problems involved in, respectively, restoring, or forming, a barrier to CWL while accommodating rapid somatic growth. J. Morphol. 256:134–145, 2003. © 2003 Wiley‐Liss, Inc.
Do pregnant lizards resorb or abort inviable eggs and embryos? Morphological evidence from an Australian skink, Pseudemoia pagenstecheri
Authors: Blackburn Daniel G. , Weaber Kera K. , Stewart James R. , Thompson Michael B.
Published: March 2003

Although pregnant viviparous squamates are sometimes claimed to be able to resorb inviable eggs and embryos from the uterus, definitive evidence for such resorption is not available. After placing pregnant female Pseudemoia pagenstecheri into conditions under which embryonic development is terminated, we periodically harvested the gravid oviducts and examined them histologically. Females contained abnormal and degenerating eggs and embryos that had died in various stages of development. Dead embryos had undergone extensive cytolysis, dissolution, and aseptic necrosis and vitelline masses showed signs of deterioration and passage down the oviduct. The uterine mucosa lay in direct contact with the vitelline material, with no intact shell membrane intervening between them. Yolk was sometimes displaced into the exocoelom and allantoic cavity due to rupture of the extraembryonic membranes. Histological examination revealed no evidence of the uptake of yolk by the uterine epithelium or its accumulation in the subepithelial connective tissue. In many specimens, the uterine epithelium showed minuscule, apical granules. The position, appearance, and staining properties of the granules suggests them to be secretory, a manifestation of placentotrophy. Our observations indicate that P. pagenstecheri females retain dead eggs and embryos for several weeks or longer, yet do not resorb them during that period. This lizard is the second placentotrophic skink species in which resorption has been suspected, but in which abortive eggs appear to be retained or extruded instead of being resorbed by the oviducts. Researchers should not assume that squamates can digest and resorb oviductal eggs without definitive morphological evidence. J. Morphol. 256:219–234, 2003. © 2003 Wiley‐Liss, Inc.
Herpes simplex virus type 1 can either suppress or enhance human immunodeficiency virus type 1 replication in CD4‐positive T lymphocytes
Authors: Calistri Arianna , Parolin Cristina , Palù Giorgio
Published: March 2003

It was proposed recently that CEM CD4‐positive T cells infected chronically by herpes simplex virus type 1 (HSV‐1) and human immunodeficiency virus type 1 (HIV‐1) (CEMHSV/HIV) may be used as a model for studying HIV/HSV interactions. To ascertain whether HSV‐HIV coinfection of T lymphocytes has a role in promoting progression of lentiviral infection, T cells infected chronically by either HSV‐1 (CEMHSV) or HIV‐1 (CEMHIV) were challenged with a superinfecting dose of HIV‐1 or HSV‐1. The results show a positive influence on HIV growth when CEMHIV cells were superinfected with HSV‐1 to an extent that was dependent on the multiplicity of superinfection used. In contrast, HIV superinfection of CEMHSV cells resulted in a delay of HIV‐1 production and in a lack of HSV‐mediated LTR transactivation. These effects were due to cell growth inhibition and apoptosis, resulting from persistent HSV‐1 infection. Treatment of CEMHSV with acyclovir inhibited completely the HSV‐1 cytopathic effects and allowed efficient HIV‐1 replication. These data may be relevant in clarifying the role of HIV/HSV interaction in the pathogenesis of AIDS. J. Med. Virol. 70:163–170, 2003. © 2003 Wiley‐Liss, Inc.
Hepatitis C virus E2 and NS5A region variability during sequential treatment with two interferon‐α preparations
Authors: Mangoni Emanuele Durante , Forton Daniel M. , Ruggiero Giuseppe , Karayiannis Peter
Published: March 2003

To determine the pattern and significance of the HCV genetic heterogeneity before and during treatment with recombinant‐2b or lymphoblastoid α‐interferon, hypervariable region 1 (HVR‐1) and NS5A quasispecies were characterised by cloning and sequencing in 12 HCV‐1b‐infected subjects. Patients were either responder‐relapsers or non‐responders to treatment. Extensive amino acid sequence analysis was applied to reveal the significance of HCV variation at key sites within HVR‐1 and NS5A regions. Genetic complexity, genetic diversity, and the non‐synonymous to synonymous substitution ratios of HVR‐1 quasispecies decreased during treatment in responder‐relapser patients only, and more markedly so following lymphoblastoid α‐interferon. In non‐responders, the HVR‐1 quasispecies broadened. Amino acids G406 and Q409, which represent a major viral epitope, were highly conserved throughout treatment. Responder‐relapser patients had a higher mutation frequency in NS5A than non‐responders. Lymphoblastoid α‐interferon promoted the selection of intermediate Interferon Sensitivity Determining Region (ISDR) sequences, whereas recombinant‐2b α‐interferon favoured maintenance or selection of conserved ISDR sequences. Variability upstream of the ISDR was associated with treatment response, but the amino acid substitutions conferring higher replicative ability to in vitro HCV replicons were absent in in vivo isolates. In conclusion, the pattern of HVR‐1 quasispecies evolution correlates with the clinical response, and the conservation of specific amino acids may be useful for immune targeting in vivo. In responder‐relapser patients, the initial HVR‐1 evolution resembles that found in sustained responders. Variability within the entire NS5A, as opposed to a single region (ISDR), may have a role in influencing α‐interferon treatment outcome. A differential effect of different α‐interferon preparations on HCV quasispecies kinetics may exist. J. Med. Virol. 70:62–73, 2003. © 2003 Wiley‐Liss, Inc.
Molecular epidemiological and clinical aspects of hepatitis D virus in a unique triple hepatitis viruses (B, C, D) endemic community in Taiwan
Authors: Lu Sheng‐Nan , Chen Tsung‐Ming , Lee Chuan‐Mo , Wang Jing‐Houng , Tung Hung‐Da , Wu Jaw‐Ching
Published: March 2003

The molecular epidemiological and clinical aspects of hepatitis D virus (HDV) in a unique HBV, HCV, and HDV triple virus endemic community in southern Taiwan were investigated. A total of 2,909 residents aged 45 or older were screened for hepatitis B surface antigen (HBsAg), anti‐HCV antibody, and anti‐HDV antibody (specifically for HBsAg‐positive carriers). Factors that might be associated with HDV infection, viral nucleic acid detection, and genotyping of HBV, HCV, and HDV were investigated. The prevalence of HBsAg and anti‐HCV were 12.6% (366/2,909) and 41.6% (1,227/2,909), respectively. For HBsAg carriers, 15.3% (56/366) were positive for anti‐HDV assay. Living in a higher endemic district of HCV infection (odds ratio [OR] = 3.2; 95% confidence interval [CI] = 1.7–6.3), male gender (OR = 1.9; 95% CI = 1.1–3.6) and co‐infection with HCV (OR = 1.8; 95% CI = 1.0–3.3) were significantly independent factors associated with HDV infection. The detection rate of HDV RNA among anti‐HDV‐positive patients was only 12.7% (7/55). The mean HBV titer of triple infection group was significantly lower than in the HBV/HDV co‐infection group (2.23 vs 3.05 in log10, copies/ml, P = 0.046). HCV RNA detection among the triple infection group showed 47.4% (9/19) viremia rate and viral loads of 579,121 IU/ml in median (16,803–1,551,190 IU/ml). The prevalent genotype of HBV was type B (23/25); HCV was 1b (7/9) and HDV was IIa/IIb (4/4). Only the presence of HCV RNA predicted the presence of elevated ALT significantly (OR = 25.0; 95% CI = 3.39–184.6). In conclusion, the geographical aggregation of HDV infection paralleled that of HCV infection in this community. HCV suppressed the replication of HBV among triple vital infection patients. HBV and HDV lapsed into a remission or nonreplicative phase in most cases, and HCV acted as a dominant factor in triple viral‐infected individuals. Only the presence of HCV RNA was associated with elevated ALT values, but not HBV or HDV. J. Med. Virol. 70:74–80, 2003. © 2003 Wiley‐Liss, Inc.
Accurate model of InxGa1−xAsyP1−y/InP active waveguides for optimal design of switches
Authors: Petruzzelli V.
Published: March 2003

Both the longitudinal and transverse charge diffusion terms in the rate equations as well as the spreading effect of the injected charge in the active layer are taken into account for a complete model of active twin ridge InGaAsP/InP‐waveguides. A dedicated computer code, relying on an optimized beam propagation method (BPM) based on the method of lines (MoL–BPM), is written. The computer code is used for the optimal design of a travelling‐wave switch and to simulate the bidirectional propagation for the design of a Fabry–Perot switch. This last switch version is more compact with respect to the travelling wave (TW) version because a reduction of the switch length of about 20% is gained. Copyright © 2003 John Wiley & Sons, Ltd.
A uniformly stable conformal FDTD‐method in Cartesian grids
Authors: Zagorodnov I.A. , Schuhmann R. , Weiland T.
Published: March 2003

A conformal finite‐difference time‐domain algorithm for the solution of electrodynamic problems in general perfectly conducting 3D geometries is presented. Unlike previous conformal approaches it has the second‐order convergence without the need to reduce the maximal stable time step of conventional staircase approach. A novel proof for the local error rate for general geometries is given, and the method is verified and compared to other approaches by means of several numerical 2D examples. Copyright © 2003 John Wiley & Sons, Ltd.
Quasi‐analytic steady‐state solution of VCSEL rate equations including spatial hole burning and carrier diffusion losses
Authors: Jungo Marc , Erni Daniel , Baechtold Werner
Published: March 2003

We propose a new set of equations describing a cylindrical vertical cavity surface emitting laser (VCSEL) cavity under CW operation, based on the rate equations including lateral carrier diffusion. The only numerical step in the calculation consists in finding the roots of a polynomial expression. This model enables a quasi‐instantaneous calculation of the laser's light‐current characteristic, including such effects as spatial hole burning, current spreading, inhomogeneous optical intensity distribution, and diffusion losses. An analysis of the VCSELs threshold current and differential quantum efficiency is proposed, which illustrates the interplay between injected current profile and diffusion coefficient. Copyright © 2003 John Wiley & Sons, Ltd.
A simple Nyström approach for the analysis of 3D arbitrarily shaped conducting and dielectric bodies
Authors: Burghignoli P. , Di Nallo C. , Frezza F. , Galli A.
Published: March 2003

In this work, an original boundary‐integral‐equation (BIE) approach is developed for an efficient and accurate electromagnetic analysis of arbitrarily shaped three‐dimensional (3D) conducting and dielectric structures. A suitable analytical pre‐processing on the field integral representation leads to a reduction of the singularity degree of the kernels and allows a straightforward implementation of the Nyström method, based on a direct discretization of the surface integrals by means of two‐dimensional (2D) quadrature formulas. This approach presents attractive computational advantages, mainly related to the very simple determination of the matrix elements in the resulting linear system. Various numerical results have been derived for canonical 3D shapes to validate the proposed implementation, confirming the excellent features of versatility and accuracy of this numerical tool. Copyright © 2003 John Wiley & Sons, Ltd.
Estrogen receptor‐α is required for estrogen‐induced μ‐opioid receptor internalization
Authors: Micevych Paul E , Rissman Emilie F. , Gustafsson Jan‐Åke , Sinchak Kevin
Published: March 2003

Endogenous opioid circuits are pivotal for the regulation of sexual receptivity. Treatment of mice with morphine, a preferential μ‐opioid receptor (MOR) agonist, severely attenuates lordosis. Estrogen induces internalization of MOR in cell groups of the limbic‐hypothalamic lordosis‐regulating circuit. Because rapid MOR internalization is mediated by estrogen release of endogenous opioid peptides, internalization has been used as a neurochemical signature of estrogen action in the central nervous system. Together these results indicate that estrogen induces a MOR mediated inhibition of sexual receptivity. To determine which estrogen receptor, estrogen receptor‐α (ERα) or estrogen receptor‐β (ERβ), mediates MOR internalization, ERα knockout (ERαKO), ERβ knockout (ERβKO) and wild‐type (WT) mice were used in the present study. WT, ERαKO and ERβKO mice had similar MOR distributions in the limbic‐hypothalamic lordosis‐regulating circuit. Estrogen treatment internalized MOR in the medial preoptic nucleus of ovariectomized WT and ERβKO, but not ERαKO mice. Treatment of ERαKO mice with the selective endogenous MOR ligand, endomorphin‐1, induced levels of MOR internalization similar to WT mice suggesting that MOR in ERαKO mice could be activated and were probably functional. The results of the present experiments indicate that ERα is required for estrogen‐induced MOR internalization and suggest that ERα can mediate rapid actions of estrogen. © 2002 Wiley‐Liss, Inc.
Monoaminergic control of vasopressin and VIP expression in the mouse suprachiasmatic nucleus
Authors: Vacher C. M. , Frétier P. , Créminon C. , Seif I. , De Maeyer E. , Calas A. , Hardin‐Pouzet H.
Published: March 2003

We studied the effects of serotonin and noradrenaline on the expression of arginine‐vasopressin (AVP) and vasoactive intestinal peptide (VIP) in the suprachiasmatic nucleus (SCN). We used transgenic Tg8 mice knockout for the MAO‐A (monoamine oxidase A) gene, which are characterized by increased amounts of serotonin and noradrenaline in brain compared to wild‐type mice (C3H). The MAO‐A deficiency caused an increase in AVP and VIP expression (determined by immunohistochemistry, enzyme immunoassay, and in situ hybridization) compared to C3H mice. The number of peptidergic neurons was also increased. Inhibiting serotonin or noradrenaline synthesis in Tg8 mice by the administration of parachlorophenylalanine or α‐methylparatyrosine, respectively, the amounts of AVP, VIP and their mRNAs were decreased, but not the number of peptidergic neurons. This study indicates that serotonin and noradrenaline stimulate AVP and VIP expression, and could participate in the differentiation of the neurochemical phenotype in the mouse SCN. © 2002 Wiley‐Liss, Inc.
Tumor suppressor gene BRCA‐1 is expressed by embryonic and adult neural stem cells and involved in cell proliferation
Authors: Korhonen L. , Brännvall K. , Skoglösa Y. , Lindholm D.
Published: March 2003

BRCA‐1 is a tumor suppressor gene that plays a role in DNA repair and cellular growth control. Here we show that BRCA‐1 mRNA is expressed by embryonic rat brain and is localized to the neuroepithelium containing neuronal precursor cells. The expression of BRCA‐1 decreases during rat brain development, but BRCA‐1 is expressed postnatally by proliferating neuronal precursor cells in the developing cerebellum. Neural stem cells (NSC) prepared from embryonic rat brain and cultured in the presence of epidermal growth factor were positive for BRCA‐1. Induction of NSC differentiation resulted in down‐regulation of BRCA‐1 expression as shown by RNA and protein analyses. In addition to embryonic cells, BRCA‐1 is also present in NSC prepared from adult rat brain. In adult rats, BRCA1 was expressed by cells in the walls of brain ventricles and in choroid plexus. The results show that BRCA‐1 is present in embryonic and adult rat NSC and that the expression is linked to NSC proliferation. © 2003 Wiley‐Liss, Inc.
Pressure‐ and temperature‐dependent Raman studies of KNbW2O9 hexagonal tungsten bronze
Authors: Mączka M. , Souza Filho A. G. , Freire P. T. C. , Mendes Filho J. , Kojima S. , Hanuza J. , Majchrowski A.
Published: March 2003

Pressure‐ and temperature‐dependent Raman studies were performed on KNbW2O9 ferroelectric hexagonal tungsten bronze single crystal. The results suggest that some structural changes, possibly phase transitions, connected with tilting of the WO6 octahedra occur in this material at around 290–350 K and 1.0–1.4 GPa. No changes in the spectra could be observed at the 523 and 543–553 K phase transitions. The data indicate that these phase transitions lead to only weak changes in the vibrational properties of KNbW2O9, which were not observed owing to the large bandwidth of the Raman bands. The Raman studies suggest, therefore, that the structure of the unknown phase, existing below 553 K, differs slightly form the orthorhombic structure present above 553 K. The pressure‐dependent study revealed that the 52 cm−1 band, assigned to external vibrations of the WO6 octahedron, consists at ambient temperature and pressure of two overlapping bands. These bands become well separated at high pressure. Copyright © 2003 John Wiley & Sons, Ltd.
Raman identification of materials used for jewellery and mosaics in Ifriqiya
Authors: Colomban Philippe , March Grégory , Mazerolles Léo , Karmous Tijani , Ayed Naceur , Ennabli Abdelmajid , Slim Hédi
Published: March 2003

Beads, rings and mosaic tessarae from Tunisia (Carthage and Utica, 1st centuries BC and AD, El Djem, 2nd–3rd centuries and Mahdia, 10th century) were analysed by Raman spectroscopy for non‐destructive differentiation of various types of glasses (most have Si‐ and Na/Ca‐rich compositions, some others are lead‐containing glass) and identification of synthetic or natural minerals (crystal or stone). The results are discussed in the light of chemical analyses. A green glass is coloured by a Cr‐based nanosized pigment and a red mosaic tesserae is obtained by a colloidal dispersion of gold (Cassius purple). Cassiterite (SnO2) is used as an opacifier or fluxing agent. The examination of glass mosaic and jewellery microstructure shows that some pieces are made of sintered glass, i.e. using a paste technology. Copyright © 2003 John Wiley & Sons, Ltd.
The role of quantitative and qualitative research in industrial studies of tourism
Authors: Davies Brian
Published: March 2003

Many areas of research in tourism concentrate on quantitative or qualitative studies. Some even discuss the complementarity between the two types of studies. Hardly considered are the possibilities for combining such works within an integrated framework that also considers the business environment in which tourism operates. The purpose of this paper is to return to long neglected possibilities by reinvestigating areas of methodology and epistemology concerned with the generation of a framework that embraces both quantitative and qualitative research. A hypothetical example, in terms of industrial organisation and strategic decision making, is introduced discussing the possibilities for the triangulation of methods and paradigms and the role of the business environment. The conclusion is that an improved understanding of the tourism business requires a broader research methodology than presently exists. Both types of research and the dynamic context of tourism are important and need to be combined within an integrated framework. It has been concerned with the construction of integrating frameworks that embrace an alternative logic of inference and the context of the tourism business environment. This requires refinements of existing approaches together with a broader research methodology. Only by establishing such frameworks will an improved understanding of the tourism industry be achieved. The suggested framework presented here, with particular reference to industrial organisation and strategic decision making by tourism suppliers, is not offered as a panacea. For future work, the validity and choice of framework rest squarely on how the world and ‘truth’ are viewed. However, within this, the contribution of triangulated quantitative and qualitative research should help understanding by studying phenomena in their natural setting and in terms of the meanings people have of them. This should lead to a ‘truer analysis’ of business behaviour and hence a more purposeful investigation of hotels, tour operators, travel agents and the business of tourism in general. It is in seeking to produce this ‘truer analysis’ that future research activities need to concentrate. Copyright © 2003 John Wiley & Sons, Ltd.
Kinetics and mechanism of the gas‐phase OH hydrogen abstraction reaction from methionine: A quantum mechanical approach
Authors: Galano Annia , Alvarez‐Idaboy J. Raúl , Cruz‐Torres Armando , Ruiz‐Santoyo Ma. Esther
Published: March 2003

Unrestricted density functional theory (BHandHLYP) calculations have been performed, using the 6‐311G(d,p) basis sets, to study the gas‐phase OH hydrogen abstraction reaction from methionine. The structures of the different stationary points are discussed. Ring‐like structures are found for all the transition states. Reaction profiles are modeled including the formation of prereactive complexes, and negative net activation energy is obtained for the gamma H‐abstraction channel. A complex mechanism is proposed, and the rate coefficients are calculated using transition state theory over the temperature range 250–350 K. The rate coefficients are proposed for the first time and it was found that in gas phase the hydrogen abstraction occurs almost exclusively from the gamma site. The large overall rate coefficient for the methionine + OH reaction compared to other free amino acids could explain the significant role of methionine in the oxidative processes. The following expressions in [L/(mol s)] are obtained for the alpha, beta, and gamma H‐abstraction channels, and for the overall temperature‐dependent rate constants, respectively: kα = (3.42 ± 0.11) × 108 exp[(−1118 ± 9)/T], kβ = (1.13 ± 0.03) × 108 exp[(−1070 ± 8)/T], kγ = (2.11 ± 0.26) × 107 exp[(2049 ± 34)/T], and ktot = (2.12 ± 0.26) × 107 exp[(2047 ± 34)/T]. © 2003 Wiley Periodicals, Inc. Int J Chem Kinet 35: 212–221, 2003
Kinetics of the reaction of OH radicals with acetylene in 25–8000 torr of air at 296 K
Authors: Sørensen M. , Kaiser E. W. , Hurley M. D. , Wallington T. J. , Nielsen O. J.
Published: March 2003

Relative rate techniques were used to study the kinetics of the reaction of OH radicals with acetylene at 296 K in 25–8000 Torr of air, N2/O2, or O2 diluent. Results obtained at total pressures of 25–750 Torr were in good agreement with the literature data. At pressures >3000 Torr, our results were substantially (∼35%) lower than that reported previously. The kinetic data obtained over the pressure range 25–8000 Torr are well described (within 15%) by the Troe expression using ko = (2.92 ± 0.55) × 10−30 cm6 molecule−2 s−1, k∞ = (9.69 ± 0.30) × 10−13 cm3 molecule−1 s−1, and Fc = 0.60. At 760 Torr total pressure, this expression gives k = 8.49 × 10−13 cm molecule−1 s−1. © 2003 Wiley Periodicals, Inc. Int J Chem Kinet 35: 191–197, 2003
Factors affecting the antibacterial effects of Nd:YAG laser in vivo
Authors: Meral Gökçe , Tasar Ferda , Kocagöz Sesin , Sener Cem
Published: March 2003

Background and Objectives

One of the main advantages of laser surgery is it's bactericidal effect which reduces the risk of postoperative infections. Several study designs have been set to investigate this effect. Aim of this study was to research if the bactericidal effect of laser tool was affected from several factors in vitro studies.

Study Design/Materials and Methods

To determinate and investigate the bactericidal effect of laser in an original model, α‐hemolytic streptococcus, Bacterioides fragilis, Neisseria, Streptococcus salivarius, Staphylococcus aureus, and Candida albicans were prepared in 104, 106 and 108 inoculum and placed in Mueller‐Hinton Broth which have five different proportions of sheep blood. Samples which exposed with various energy levels of Nd:YAG laser were spread on agar plates, and at the end of an incubation time the colonization counted comparatively. The lowest energy level without colonization was accepted as minimal bactericidal energy level.

Results

Highest minimum bactericidal energy level is used for α‐hemolytic streptococcus and lowest values for neisseria. Bactericidal effect decreased on suspensions, of which population of microorganisms are high and hemoglobin concentration was high in the broth.

Conclusions

These findings suggest that the Nd:YAG laser has a higher bactericidal effect when sheep blood is added to the media. Factors like population and type of bacteria in the irradiated suspension affect minimum bactericidal energy level. Lasers Surg. Med. 32:197–202, 2003. © 2003 Wiley‐Liss, Inc.
Efficacy of NaOCl/H2O2 irrigation and GaAlAs laser in decontamination of root canals in vitro
Authors: Kreisler M. , Kohnen W. , Beck M. , Al Haj H. , Christoffers A.B. , Götz H. , Duschner H. , Jansen B. , d'Hoedt B.
Published: March 2003

Background and Objectives

To investigate the bactericidal effect of an 809 nm semiconductor laser alone, and in combination with NaOCl/H2O2 irrigation in root canals in vitro.

Study Design/Materials and Methods

A total of 72 human single‐rooted teeth extracted for periodontal reasons were included. The crowns were removed, the roots shortened to a length of 12 mm, and the canals enlarged up to an apical size of #50 file. The specimens were autoclaved and incubated with a suspension of Streptococcus sanguinis (ATCC 10556). Laser irradiation was performed on a PC‐controlled XY translation stage. A 200 micron optic fiber was used. Twelve specimens were irradiated at a power output of 1.5, 3.0, and 4.5 W in the cw‐mode. The total irradiation time was 60 seconds per canal. Twelve specimens were rinsed with NaOCl and H2O2 only, 12 were rinsed and laser treated, and 12 served as untreated controls. After laser treatment, the specimens were sonicated and the bacterial growth was examined by counting colony forming units on blood agar plates. Temperature changes at the outer root surface during irradiation were registered by means of thermocouples. Treated and control specimens were investigated by means of scanning electron microscopy.

Results

Mean bacterial reductions of 0.35 log steps at a power output of 1.5 W, 1.44 at 3.0 W, and 2.84 at 4.5 W were calculated. Bacterial reduction by the NaOCl/H2O2 solution alone was 1.48 and comparable to that achieved by irradiation at 3.0 W. With a log kill 2.85, the combination of rinsing and laser irradiation at 3.0 W resulted in a further significant bacterial reduction as compared to rinsing alone (P = 0.004). Irradiation did not result in excessive heat generation at the root surface. Carbonization of the root canal wall was observed in single teeth at 3.0 and 4.5 W and no controlled sealing of the dentinal tubules could be achieved in the root canal.

Conclusions

The application of the diode laser might be an adjunct to conventional endodontic treatment when used in combination with a NaOCl/H2O2 solution. Lasers Surg. Med. 32:189–196, 2003. © 2003 Wiley‐Liss, Inc.
Independence results for weak systems of intuitionistic arithmetic
Authors: Moniri Morteza
Published: March 2003

This paper proves some independence results for weak fragments of Heyting arithmetic by using Kripke models. We present a necessary condition for linear Kripke models of arithmetical theories which are closed under the negative translation and use it to show that the union of the worlds in any linear Kripke model of HA satisfies PA. We construct a two‐node PA‐normal Kripke structure which does not force iΣ2. We prove i∀1⊬ i∃1, i∃1⊬ i∀1, iΠ2⊬ iΣ2and iΣ2⊬ iΠ2. We use Smorynski's operation Σ′ to show HA ⊬ lΠ1.
Sensing Behavior of Fluorescent Cyclodextrin/Peptide Hybrids Bearing a Macrocyclic Metal Complex
Authors: Furukawa Shuntaro , Mihara Hisakazu , Ueno Akihiko
Published: March 2003

Two kinds of cyclodextrin/peptide (CD/peptide) hybrids bearing ZnII‐cyclen or cyclen, dansyl and β‐cyclodextrin (β‐CD) units have been synthesized as chemosensors for organic anionic molecules. ZnII‐cyclen serves as a ligand site and β‐CD is a receptor site for guest molecules, while the dansyl unit acts as a fluorescent probe. Examination of the fluorescence behaviors of these CD/peptides suggest that the hybrid containing Zn2+ has larger binding constants with respect to anionic molecules than that without Zn2+.

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Insulin‐like growth factor binding protein‐1 over‐expression in transgenic mice inhibits hepatic preneoplasia
Authors: Lu Suying , Archer Michael C.
Published: March 2003

Insulin‐like growth factor binding protein‐1 (IGFBP‐1) is synthesized in the liver and regulates the mitogenic effects of the insulin‐like growth factors (IGFs). The evidence that IGFBP‐1 plays a role in hepatocarcinogenesis, however, is equivocal. We have, therefore, investigated the development of preneoplastic hepatic lesions in transgenic mice in which the human IGFBP‐1 gene is under the control of the mouse metallothionein promoter. The lesions were induced by treating 15‐d‐old male mice with a single intraperitoneal injection of 5 mg/kg diethylnitrosamine (DENA). Lesions were scored when the mice were 28 wk of age. Quantitative microscopy of liver sections revealed that significantly fewer transgenic mice treated with zinc to activate the transgene had focal lesions compared to either transgenic mice not treated with zinc or wild‐type mice treated with zinc (36.4% versus 85.7% and 83.3%, respectively, P < 0.05 in each case). Zinc‐treated transgenic mice also had significantly fewer lesions per liver (11.5 ± 5.0 versus 74.7 ± 18.4 and 59.4 ± 15.6, respectively, P < 0.01 in each case) and a smaller percentage of liver volume occupied by lesions (0.2 ± 0.1 versus 1.4 ± 0.3 and 1.1 ± 0.4 respectively, P < 0.05 in each case). Immunohistochemical staining showed that both IGF‐I and IGF‐II were overexpressed in most of the lesions. These results show that expression of the IGFBP‐1 transgene leads to a marked inhibition of hepatic preneoplasia, possibly by decreasing the mitogenic activity of IGF‐I and/or IGF‐II. This study adds new evidence to the notion that the IGF axis plays an important role in liver cancer development. © 2003 Wiley‐Liss, Inc.
Sensorimotor integration in movement disorders
Authors: Abbruzzese Giovanni , Berardelli Alfredo
Published: March 2003

Although current knowledge attributes movement disorders to a dysfunction of the basal ganglia–motor cortex circuits, abnormalities in the peripheral afferent inputs or in their central processing may interfere with motor program execution. We review the abnormalities of sensorimotor integration described in the various types of movement disorders. Several observations, including those of parkinsonian patients' excessive reliance on ongoing visual information during movement tasks, suggest that proprioception is defective in Parkinson's disease (PD). The disturbance of proprioceptive regulation, possibly related to the occurrence of abnormal muscle‐stretch reflexes, might be important for generating hypometric or bradykinetic movements. Studies with somatosensory evoked potentials (SEPs), prepulse inhibition, and event‐related potentials support the hypothesis of central abnormalities of sensorimotor integration in PD. In Huntington's disease (HD), changes in SEPs and long‐latency stretch reflexes suggest that a defective gating of peripheral afferent input to the brain might impair sensorimotor integration in cortical motor areas, thus interfering with the processing of motor programs. Defective motor programming might contribute to some features of motor impairment in HD. Sensory symptoms are frequent in focal dystonia and sensory manipulation can modify the dystonic movements. In addition, specific sensory functions (kinaesthesia, spatial–temporal discrimination) can be impaired in patients with focal hand dystonia, thus leading to a “sensory overflow.” Sensory input may be abnormal and trigger focal dystonia, or defective “gating” may cause an input–output mismatch in specific motor programs. Altogether, several observations strongly support the idea that sensorimotor integration is impaired in focal dystonia. Although elemental sensation is normal in patients with tics, tics can be associated with sensory phenomena. Some neurophysiological studies suggest that an altered “gating” mechanism also underlies the development of tics. This review underlines the importance of abnormal sensorimotor integration in the pathophysiology of movement disorders. Although the physiological mechanism remains unclear, the defect is of special clinical relevance in determining the development of focal dystonia.
Increased daytime sleepiness in Parkinson's disease: A questionnaire survey
Authors: Högl Birgit , Seppi Klaus , Brandauer Elisabeth , Glatzl Susanne , Frauscher Birgit , Niedermüller Ulrike , Wenning Gregor , Poewe Werner
Published: March 2003

We evaluated the frequency and severity of excessive daytime sleepiness in an outpatient population with Parkinson's disease in comparison to age‐matched controls and examined its relationship with antiparkinsonian drug therapy and sleep history. Increased daytime sleepiness and involuntary sleep episodes have been described in Parkinson's disease, but the etiology is not completely understood. The Epworth Sleepiness Scale (ESS), a validated questionnaire for daytime sleepiness, was prospectively administered to 99 consecutive outpatients with Parkinson's disease and 44 age‐matched controls. In addition, a short sleep‐screening questionnaire was used. The ESS revealed significantly increased daytime sleepiness in PD patients compared to controls (7.5 ± 4.6 vs. 5.8 ± 3.0, P = 0.013). The ESS score was abnormally high (10 or more) in 33 % of PD patients and 11.4% of controls (P = 0.001). ESS was not different between PD patients on levodopa monotherapy and those on levodopa and dopamine agonists, or between patients taking ergoline or non‐ergoline dopamine agonists. In PD patients and in controls, sleepiness was significantly associated with reported heavy snoring. Increased daytime sleepiness is more frequent in patients with PD than in elderly controls. Similar to controls, increased daytime sleepiness in PD patients is correlated with heavy snoring. © 2002 Movement Disorder Society
Surgical treatment of brachial plexus traction injuries in children, excluding obstetric palsy
Authors: El‐Gammal Tarek Abdalla , El‐Sayed Amr , Kotb Mohammed M.
Published: March 2003

Traumatic brachial plexus injuries in children, excluding birth palsy, are seldom reported. In this study, we report on 11 cases operated upon between 1995–1998, and followed for at least 30 months. All patients were males with an average age of 11 years (range, 3–16 years). The denervation time averaged 3.8 months (range, 1–8 months). Eight patients had two or more root avulsions; two had additional severe infraclavicular injuries. In total, 6 grafting and 25 extraplexal neurotization procedures were used. Donor nerves included the intercostal nerves, phrenic nerve, spinal accessory nerve, and contralateral C7 root. Elbow flexion was restored in all but 2 cases. Shoulder abduction varied from 30–90°, according to the method of reconstruction. Triceps recovered in 2 cases and finger and wrist extensors in 1 case. Wrist and finger flexion was obtained in 1 case. Sensory recovery in the palm reached S2/S2+. Harvesting the phrenic nerve and the contralateral C7 root resulted in no residual morbidity. Compared to adults, children have a higher incidence of root avulsion, no deafferentiation pain, a higher incidence of associated skeletal injuries, and the same recovery rate of elbow and shoulder functions following plexus reconstruction, but recovery is faster. Given the frequency of root avulsions, neurotization is often required. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:14–17 2003
Incidence and significance of microscopic pathological lesions found in pedicle and recipient vessels used in microsurgical breast reconstruction
Authors: El‐Mrakby H.H. , McLean N.R. , Hodgkinson P.D. , Soames J.V.
Published: March 2003

The purpose of this study was to assess the incidence of abnormal vascular histology and to determine whether or not this was correlated with the incidence of postoperative microvascular problems. The microvascular histology of both donor and recipient vessels was studied in 38 patients (40 flaps) undergoing breast reconstruction with free TRAM flaps. Preoperative risk factors were assessed and correlated with histological changes in vessels, and both were tested against anastomotic complications. Thrombosis of either the artery or the vein of the flap was seen in 6 cases (15%), and of these, two flaps failed completely and one suffered partial necrosis. The occlusion affected the arterial anastomosis in 3 patients, and the venous anastomosis in 2 patients, while both the artery and the vein were thrombosed in one case. Preoperative risk factors such as smoking, obesity, radiotherapy, and chemotherapy were not associated with a significantly higher incidence of thrombosis or with significant histological abnormalities in vessels (P value varied between 0.3–0.06). Microvascular histology showed variable degrees of pathological changes in six flaps (15%); nevertheless, in this group, only one flap suffered a venous thrombosis, which ended in total flap loss. Among those with one or more risk factors (24 patients), only 2 had some evidence of histological abnormality of the blood vessels used for the microvascular anastomosis (P = 0.2). © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:6–9 2003
Recovery of touch after median nerve lesion and subsequent repair
Authors: Meek M.F. , Coert J.H. , Wong K.H.
Published: March 2003

Many techniques have been developed for the evaluation of peripheral nerve function. Consequently, physicians use different techniques in the clinic. This study describes the evaluation of touch after median nerve lesions in the forearm and repair. In order to evaluate touch, 25 patients, aged 11–51 years (mean, 29 years), were evaluated 3–10.5 years (mean, 5 years) after median nerve repair. The evaluation included the moving two‐point discrimination test and Semmes‐Weinstein monofilaments. We showed that 32% good–excellent results can be obtained with difficult nerve lesions. The results could have been improved if a sensory reeducation regime had been applied. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:2–5 2003
Integral equation methods for scattering by infinite rough surfaces
Authors: Zhang Bo , Chandler‐Wilde Simon N.
Published: March 2003

In this paper, we consider the Dirichlet and impedance boundary value problems for the Helmholtz equation in a non‐locally perturbed half‐plane. These boundary value problems arise in a study of time‐harmonic acoustic scattering of an incident field by a sound‐soft, infinite rough surface where the total field vanishes (the Dirichlet problem) or by an infinite, impedance rough surface where the total field satisfies a homogeneous impedance condition (the impedance problem). We propose a new boundary integral equation formulation for the Dirichlet problem, utilizing a combined double‐ and single‐layer potential and a Dirichlet half‐plane Green's function. For the impedance problem we propose two boundary integral equation formulations, both using a half‐plane impedance Green's function, the first derived from Green's representation theorem, and the second arising from seeking the solution as a single‐layer potential. We show that all the integral equations proposed are uniquely solvable in the space of bounded and continuous functions for all wavenumbers. As an important corollary we prove that, for a variety of incident fields including an incident plane wave, the impedance boundary value problem for the scattered field has a unique solution under certain constraints on the boundary impedance. Copyright © 2003 John Wiley & Sons, Ltd.
On the existence of solutions to the Navier–Stokes equations of a two‐dimensional compressible flow
Authors: Erban Radek
Published: March 2003

We consider the Navier–Stokes equations for compressible, barotropic flow in two space dimensions. We introduce useful tools from the theory of Orlicz spaces. Then we prove the existence of globally defined finite energy weak solutions for the pressure satisfying p(ϱ) = aϱlogd(ϱ) for large ϱ. Here d>1 and a > 0. Copyright © 2003 John Wiley & Sons, Ltd.
Influence of unpumped EDF position and auxiliary pump wavelength on L‐band EDFA performance
Authors: Sun Junqiang
Published: March 2003

Large gain enhancement in a novel long‐wavelength band (L‐band) erbium‐doped fiber amplifier (EDFA) is demonstrated by the cascade of pumped and unpumped erbium‐doped fibers. By utilizing an injected conventional wavelength band (C‐band) laser as an auxiliary pump signal, an approximately 7.5‐dB gain improvement is achieved. The EDFA performances are analyzed and explained in terms of C‐band wavelength, and pumped and unpumped erbium‐doped fiber sequence. The results indicate that there is a tradeoff between gain enhancement and noise figure reduction. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 37: 95–98, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10834
A 74%, 1.56–2.71 GHz, wide‐tunable LC‐tuned VCO in 0.35‐μm CMOS technology
Authors: Oh Seung‐Min , Kim Chang‐Wan , Lee Sang‐Gug
Published: March 2003

A wide‐tuning monolithic LC‐tuned VCO is presented. The proposed VCO accomplishes wide tuning by utilizing binary weighted switched varactor combinations operating at minimum or maximum value, in addition to a linearly varying interpolation varactor. Measurements show 74% of tuning at a range of 1.56–2.71 GHz, with the phase noise ranging from −136 dBc/Hz to −108 dBc/Hz at 1 MHz offset. The VCO is implemented in 0.35‐μm CMOS technology and dissipates 10.3 mA from a 3‐V supply. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 37: 98–100, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10835
An undersampled high‐directivity microstrip patch array with a reduced number of radiating elements inspired on the Sierpinski fractal
Authors: Anguera Jaume , Montesinos Gemma , Puente Carles , Borja Carmen , Soler Jordi
Published: March 2003

A high‐directivity microstrip array using multilevel elements based on fractal geometry is theoretically compared with an array using circular patches. Within the same electrical area, the same directivity can be obtained. However, the number of elements for the fractal‐based array is 2.84 times less, thus reducing the complexity of the feeding network and the overall array. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 37: 100–103, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10836