bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anatomy of a hemiramphid pharyngeal mill with reference to arrhamphus sclerolepis krefftii (steindachner) (teleostei: hemiramphidae)
Authors: Tibbetts Ian R. , Carseldine Lee 
Published: December 2002

AbstractThe structure and function of the pharyngeal jaw apparatus (PJA) and postpharyngeal alimentary tract of Arrhamphus sclerolepis krefftii, an herbivorous hemiramphid, were investigated by dissection, light and scanning electron microscopy, and X‐ray analysis of live specimens. A simple model of PJA operation is proposed, consisting of an adductive power stroke of the third pharyngobranchial that draws it posteriorly while the fifth ceratobranchial is adducted, and a return stroke in which the third pharyngobranchial bone is drawn anteriorly during abduction of the fifth ceratobranchial. Teeth in the posteromedial region of the PJA are eroded into an occlusion zone where the teeth of the third pharyngobranchial are spatulate incisiform and face posteriorly in opposition to the rostrally oriented spatulate incisiform teeth in the wear zone of the fifth ceratobranchial. The shape of the teeth and their pedestals (bone of attachment) is consistent with the model and with the forces likely to operate on the elements of the PJA during mastication. The role of pharyngeal tooth replacement in maintaining the occlusal surfaces in the PJA during growth is described. The postpharyngeal alimentary tract of A. sclerolepis krefftii comprises a stomachless cylinder that attenuates gradually as it passes straight to the anus, interrupted only by a rectal valve. The ratio of gut length to standard length is about 0.5. Despite superficial similarities to the cichlid PJA (Stiassny and Jensen [1987] Bull Mus Comp Zool 151:269–319), the hemiramphid PJA differs in the fusion of the third pharyngobranchial bones, teeth in the second pharyngobranchials and the fifth ceratobranchial face anteriorly, the presence of a slide‐like diarthroses between the heads of the fourth epibranchials and the third pharyngobranchial, the occlusion zone of constantly wearing teeth, and the unusual form of the muscularis craniopharyngobranchialis. The functional relationship between these structures is explained and the consequence for the fish of a complex PJA and a simple gut is discussed. J. Morphol. 255:228–243, 2003. © 2002 Wiley‐Liss, Inc.
The role of specific normal modes during non‐Born–Oppenheimer dynamics: the S1–S0 internal conversion of β‐carotene interrogated on a femtosecond time‐scale with coherent anti‐Stokes Raman scattering
Authors: Siebert T. , Maksimenka R. , Materny A. , Engel V. , Kiefer W. , Schmitt M. 
Published: December 2002

AbstractThe population flow from the first excited singlet state (S1) to the electronic ground state (S0), facilitated through the S1–S0 internal conversion, and the subsequent internal vibrational energy redistribution and vibrational cooling processes are monitored selectively with respect to the different forms of nuclear motion in all‐trans‐β‐carotene. This is realized by exciting the molecule into the second excited singlet state (S2) with an auxiliary pump laser pulse and interrogating the population recovery into the electronic ground state by means of a time‐delayed, coherent anti‐Stokes Raman (CARS) process. This spectroscopic scheme is referred to as a pump‐CARS scheme in analogy to the classical pump–probe scheme in time‐resolved spectroscopy. Here, the profound enhancement of the CARS signal intensity in the case of a Raman resonance to a specific vibrational mode is utilized as an intensity filter that amplifies the signal from the vibrational modes of interest, making the contributions from other vibrational modes negligible. This filter allows for the population flow in a specific vibrational mode to be monitored as the radiationless electronic transition between the S1 and S0 state takes place. This spectroscopic scheme opens up the possibility of identifying the vibrational motion with a large‐amplitude motion in the CC double bond symmetric stretch as the primary acceptor of population from the S1 state. A mechanism with which the other normal modes are populated is postulated. Copyright © 2002 John Wiley & Sons, Ltd.
Dual–pump CARS for the simultaneous detection of N2, O2 and CO in CH4 flames
Authors: Beyrau F. , Datta A. , Seeger T. , Leipertz A. 
Published: December 2002

AbstractThe application of a modified dual‐pump CARS set‐up for the simultaneous determination of temperature and N2, O2 and CO concentration is demonstrated. This technique offers numerous advantages, which are discussed in detail and presented for the investigation of a partially premixed flame. In comparison with a standard vibrational CARS set‐up, consisting of one Nd:YAG laser and one broadband dye laser together with a single spectrometer and camera, only one additional narrowband dye laser is needed. By shifting the spectral profile of the broadband dye laser providing the excitation profile, N2 and CO were excited simultaneously from a single narrowband–broadband laser combination as in an usual CARS set‐up with degenerate pump wavenumbers. Additionally, oxygen was excited using the same broadband laser but another narrowband laser in a dual‐pump CARS configuration. The technique presented is not limited to the three species investigated here. Copyright © 2002 John Wiley & Sons, Ltd.
CARS temperature mapping in a cryogenic LOX–H2 rocket combustion chamber under supercritical conditions
Authors: Klimenko D. N. , Clauss W. , Oschwald M. , Smith J. , Mayer W. 
Published: December 2002

AbstractCoherent anti‐Stokes Raman spectroscopy (CARS) was applied for temperature measurements in a high‐pressure cryogenic liquid oxygen–hydrogen rocket model combustor. The combustor was operated at 6 MPa, above the supercritical pressure of the propellants. H2 and H2O molecules were probed simultaneously using a dual‐broadband CARS setup and degenerate CARS setup with a single dye laser. The diagnostic set‐up at the test site was adapted to the high level of vibrations experienced during tests by several measures: the laser system was positioned in a separate room next to the test cell, a heavy‐duty tri‐axial translation stage for positioning the beam guiding optics and focusing lenses in the test cell was specially designed to be insensitive to vibrational excitation. The combustor was operated at two hydrogen injection temperatures, 65 and 117 K. In the low hydrogen temperature tests no CARS signal could be obtained. At a higher hydrogen temperature (∼117 K), successful temperature mapping of the flame was performed at two cross‐sections, 50 and 80 mm downstream of the injector. Bimodal temperature distributions were observed at the 80 mm position, indicating strong flame and flow oscillations. Copyright © 2002 John Wiley & Sons, Ltd.
Femtosecond degenerate four‐wave mixing of pyridine and its biologically relevant derivatives
Authors: Frey H. M. , Müller A. , Leutwyler Samuel 
Published: December 2002

AbstractTime‐resolved degenerate four‐wave mixing experiments in the femtosecond time domain were employed to record the rotational ground‐state dynamics of the N‐heteroaromatic molecules pyridine, pyrimidine and pyrazine in the gas phase. Pyrimidine is an important molecular building block of several nucleic acid bases. The method records the time‐dependent change in third‐order polarization of a sample after coherent excitation. All three molecules are asymmetric tops in the oblate limit. From the analysis of the transients we obtained highly accurate averages of the two larger ground‐state rotational constants A and B. Copyright © 2002 John Wiley & Sons, Ltd.
On far‐wing Raman profiles by CO2
Authors: Benec'h S. , Rachet F. , Chrysos M. , Buldyreva J. , Bonamy L. 
Published: December 2002

AbstractThe anisotropic scattering spectrum of the symmetric stretching ν1 band by CO2 was recorded up to the far Stokes wing, and its theoretical analysis was attempted through the non‐Markovian energy‐corrected sudden approximation—a useful approach which has thus far been successfully applied to the anisotropic scattering spectrum by N2, up to the far wing. Despite the excellent agreement observed in N2 here, a substantial inconsistency between theory and experiment was found in the wing of the spectrum. Although the influence of other missing processes or neighboring bands cannot be totally excluded, our findings rather suggest that highly anisotropic perturbers, such as CO2, are improperly described when they are handled as point‐like molecules, a cornerstone hypothesis in the approach employed. Copyright © 2002 John Wiley & Sons, Ltd.
Femtosecond degenerate four‐wave mixing study of benzene in the gas phase
Authors: Matylitsky V. V. , Jarzȩba W. , Riehn C. , Brutschy B. 
Published: December 2002

AbstractWe report on time‐resolved rotational spectroscopy of benzene molecules both in a gas cell at room temperature (298 K) and in a supersonic expansion (30 K) by femtosecond degenerate four‐wave mixing (fs‐DFWM). A detailed study of the time‐dependent structure of the rotational recurrences for the gas cell is presented. Moreover, for the first time, the fs‐DFWM technique has been applied to a medium‐sized molecule in the collision‐free environment of a seeded supersonic expansion up to a time delay of 4 ns. From these data, by fitting of the experimental spectra, a rotational constant B = 5688.95 ± 0.55 MHz was obtained for benzene in the gas cell and B = 5689.25 ± 0.11 MHz for benzene in the supersonic expansion. The combination of gas cell and supersonic jet investigations by fs‐DWFM provides a means for the structural study of large and more complex molecules. Copyright © 2002 John Wiley & Sons, Ltd.
Influence of polariton propagation on spectra of CARS from polaritons
Authors: Orlov S. N. , Polivanov Yu. N. 
Published: December 2002

AbstractWe analyzed the features of CARS from polaritons caused by the ability of polaritons to propagate over macroscopic distances in a crystal. The polariton propagation is taken into account by retaining both a driven and a free polariton wave in complete solution of the wave equation for polaritons. It is shown that the polariton propagation can broaden CARS spectra. This broadening originates from the fact that polaritons can escape from the excitation region and the value of the broadening depends on the ratio Lθ/Lp of the dimension Lθ of the excitation region along the coherently excited polariton direction and the mean path of coherent polaritons Lp. We also find that when the phase‐matching Δka = 0 for the overall anti‐Stokes generation process is not fulfilled, an additional peak in the spectrum of CARS may appear even when the polariton damping is appreciable. These predictions are corroborated by our experimental investigations of CARS from polaritons in a BeO crystal. Copyright © 2002 John Wiley & Sons, Ltd.
Determination of concentrations in ternary and quaternary molecular gas mixtures using femtosecond Raman spectroscopy
Authors: Tran H. , Lavorel B. , Faucher O. , Saint‐Loup R. , Joubert P. 
Published: December 2002

AbstractMeasurements of concentrations in gas mixtures of three and four molecular components are presented. They rely on a femtosecond time‐resolved pump–probe technique based on Raman‐induced polarization spectroscopy. The rotational time response of the molecular gas mixture is measured as a function of the pump–probe time delay. No selective frequency tunability is needed as the molecular rotational spectra are excited within the laser bandwidth. The results obtained from experiments performed at room temperature in N2O–CO2–N2 and N2O–CO2–O2–N2 mixtures are presented and the accuracy of the method is discussed. Copyright © 2002 John Wiley & Sons, Ltd.
Determination of collisional line broadening coefficients with femtosecond time‐resolved CARS
Authors: Skenderović H. , Buckup T. , Wohlleben W. , Motzkus M. 
Published: December 2002

AbstractThe potential of femtosecond time‐resolved CARS for the determination of J‐dependent line broadening coefficients is demonstrated. With the well‐developed femtosecond technique the line broadening coefficients of the H2 Q‐branch ro‐vibrational transitions are measured in pure H2 and in H2 + He and H2 + N2 mixtures. The results for pure H2 show excellent agreement with the values obtained by other groups using high‐resolution CARS in the wavenumber domain. The dependence of the experimental broadening on perturber density also shows good agreement with the behavior of broadening found in the literature: a linear dependence in the case of hydrogen and helium as perturber and explicit non‐linear behavior in the case of nitrogen. The role of inhomogeneous broadening in time domain CARS is discussed. Copyright © 2002 John Wiley & Sons, Ltd.
Determining soil permeability from pressuremeter tests
Authors: Rangeard D. , Y. Hicher P. , Zentar R. 
Published: December 2002

AbstractThis paper presents a methodology for identifying soil permeability from pressuremeter test. On the first part we present a numerical analysis of the permeability effects on the test results. We demonstrate that different drainage conditions arise during test, as a function of the loading rate and the soil permeability. We also studied the pore pressure dissipation during strain holding stages. Based on this analysis of these tests, we propose a general procedure to identify simultaneously mechanical parameters and permeability from pressuremeter tests with strain holding test stages. This procedure was applied on tests performed on natural Saint–Herblain clay. An apparatus called pressio‐triax was developed for this purpose. The values of the mechanical parameters as well as of the permeability value were found to agree very well with the values of the same parameters obtained from conventional laboratory tests. Copyright © 2002 John Wiley & Sons, Ltd.
Mohr–Coulomb MiniCLoE model Uniqueness and localization studies, links with normality rule
Authors: Chambon R. , Roger V. 
Published: December 2002

AbstractThis paper is devoted to a parametric study of a plane Mohr–Coulomb CLoE model. As CLoE models are designed with a consistency condition, it is possible to define a normality condition and to study its consequences. The positiveness of the second order work which implies the uniqueness of the solution of a small strain boundary value problem is studied firstly. Then the localization criterion is also studied. It is proved that normality has consequences similar to those for classical elasto plastic models. However if induced anisotropy is introduced in the hypoplastic CLoE model, some conclusions are no longer true. Finally plane strain experimental data are used to identify the parameters of the model. Copyright © 2002 John Wiley & Sons, Ltd.
An explicit representation of steady state response of a beam on an elastic foundation to moving harmonic line loads
Authors: Sun Lu 
Published: December 2002

AbstractA closed‐form deflection response of a beam rest is presented in this paper using the integral transform method. The theory of linear partial differential equations is used to represent the deflection of beam subjected to a moving harmonic line load in integration form. The solution is finally carried out using the inverse Fourier transform. To evaluate the integration analytically, poles of the integrand are identified with the help of algebraic equation theory. Residue theorem is then utilized to represent the integration as a contour integral in the complex plane. Closed‐form deflections and numerical results are provided for different combinations of load frequency and velocity. Copyright © 2002 John Wiley & Sons, Ltd.
Cribriform‐morular variant of papillary thyroid carcinoma: a pathological and molecular genetic study with evidence of frequent somatic mutations in exon 3 of the β‐catenin gene
Authors: Xu Bing , Yoshimoto Katsuhiko , Miyauchi Akira , Kuma Seiji , Mizusawa Noriko , Hirokawa Mitsuyoshi , Sano Toshiaki 
Published: December 2002

AbstractThe cribriform‐morular variant (C‐MV), an unusual and peculiar subtype of papillary thyroid carcinoma (PTC), has been observed frequently in familial adenomatous polyposis (FAP)‐associated thyroid carcinoma and also in sporadic thyroid carcinoma. In this paper, five young women with the C‐MV of PTC, aged 22–34 years at cancer diagnosis, are reported; two of them had attenuated FAP. Grossly, one FAP‐associated tumour and one sporadic tumour were multicentric and the others were solitary. Histologically, the tumours were encapsulated and exhibited a combination of cribriform, follicular, trabecular, solid, and papillary patterns of growth, with morular areas. Immunohistochemically, the tumour cells showed cytoplasmic expression of thyroglobulin, neuron‐specific enolase, epithelial membrane antigen, high‐ and low‐molecular‐weight cytokeratins, vimentin, and bcl‐2 protein; nuclear expression of oestrogen and progesterone receptors, and retinoblastoma protein; and cytoplasmic and nuclear accumulation of β‐catenin. Germline mutations of the adenomatous polyposis coli (APC) gene were investigated using the protein truncation test in four subjects, including two FAP individuals. Germline APC mutation was identified in only one FAP patient with the multicentric C‐MV of PTC, who had a thymidine deletion at codon 512, resulting in a frameshift leading to a premature stop codon. No loss of heterozygosity of loci close to the APC gene was detected in tumour tissues from these four patients. Somatic mutation analysis of exon 3 of the β‐catenin gene (CTNNB1) revealed alterations in seven tumours from all five individuals: one at a serine residue (codon 29), three at amino acids adjacent to serine or threonine residues (codons 22, 39, and 44), and three at other amino acids (codons 49, 54, and 56). Moreover, each of two different tumours examined from two patients with the multicentric C‐MV of PTC, had different somatic mutations of the CTNNB1 gene. Taken together, these data suggest that accumulation of mutant β‐catenin contributes to the development of the C‐MV of PTC. Copyright © 2002 John Wiley & Sons, Ltd.
Expression of intestine‐specific transcription factors, CDX1 and CDX2, in intestinal metaplasia and gastric carcinomas
Authors: Almeida Raquel , Silva Elisabete , Santos‐Silva Filipe , Silberg Debra G , Wang Jiangfu , De Bolós Carmen , David Leonor 
Published: December 2002

AbstractIntestinal metaplasia (IM) is part of a stepwise sequence of alterations of the gastric mucosa, leading ultimately to gastric cancer, and is strongly associated with chronic Helicobacter pylori infection. The molecular mechanisms underlying the onset of IM remain elusive. The aim of this study was to assess the putative involvement of two intestine‐specific transcription factors, CDX1 and CDX2, in the pathogenesis of gastric IM and gastric carcinoma. Eighteen foci of IM and 46 cases of gastric carcinoma were evaluated by immunohistochemistry for CDX1 and CDX2 expression. CDX1 was expressed in all foci of IM and in 41% of gastric carcinomas; CDX2 was expressed in 17/18 foci of IM and in 54% of gastric carcinomas. In gastric carcinomas, a strong association was observed between the expression of CDX1 and CDX2, as well as between the intestinal mucin MUC2 and CDX1 and CDX2. No association was observed between the expression of CDX1 and CDX2 and the histological type of gastric carcinoma. In conclusion, these results show that aberrant expression of CDX1 and CDX2 is consistently observed in IM and in a subset of gastric carcinomas. The association of CDX1 and CDX2 with expression of the intestinal mucin MUC2, both in IM and in gastric carcinoma, indirectly implies that CDX1 and CDX2 may be involved in intestinal differentiation along the gastric carcinogenesis pathway. Copyright © 2002 John Wiley & Sons, Ltd.
Nuclear accumulation of β‐catenin protein in Wilms' tumours†
Authors: Koesters Robert , Niggli Felix , von Knebel Doeberitz Magnus , Stallmach Thomas 
Published: December 2002

AbstractThe wnt‐signalling pathway plays an important role during both normal kidney development and Wilms' tumourigenesis. Activation of this pathway involves stabilization, intracellular accumulation, and nuclear translocation of the β‐catenin protein and may be caused by specific mutations in the β‐catenin gene itself. Such mutations have been found in about 15% of Wilms' tumours. This study has analysed the intracellular levels and subcellular distribution of β‐catenin protein in 36 primary Wilms' tumour specimens and has correlated these results with the mutational status of the β‐catenin gene. Immunohistochemistry detected faint cytoplasmic and strong membranous expression of β‐catenin protein in the epithelial compartment of all tumours examined. In contrast, nuclear immunoreactivity for β‐catenin was detected in 9 of 9 Wilms' tumours containing a mutation of the β‐catenin gene and in 15 of 27 Wilms' tumours without detectable β‐catenin mutation. Nuclear positivity, in each case, was found to be very strong, but was usually present only in a fraction of cells ranging from 5% to 10%. Among the different histological subcompartments, blastemal and mesenchymal cell nuclei preferentially stained positive, whereas cells of epithelial differentiation displayed nuclear localization of β‐catenin protein in only a single case. Furthermore, nuclear positive cells were found in Wilms' tumours of all stages and in tumours of both favourable and unfavourable histology. These data support the idea that activation of the wnt‐signalling pathway is a key oncogenic step in Wilms' tumourigenesis and that it probably involves transcriptional activation of critical target genes, carried out by β‐catenin protein in the nucleus. The fact that nuclear immunoreactivity specific for β‐catenin was detected in a significant number of Wilms' tumours in the absence of β‐catenin mutations suggests that genetic defects affecting other members of the wnt‐signalling pathway may contribute to the development of Wilms' tumours in those cases. Copyright © 2002 John Wiley & Sons, Ltd.
Protective role of endothelial nitric oxide synthase
Authors: Albrecht Ester WJA , Stegeman Coen A , Heeringa Peter , Henning Rob H , van Goor Harry 
Published: December 2002

AbstractNitric oxide is a versatile molecule, with its actions ranging from haemodynamic regulation to anti‐proliferative effects on vascular smooth muscle cells. Nitric oxide is produced by the nitric oxide synthases, endothelial NOS (eNOS), neural NOS (nNOS), and inducible NOS (iNOS). Constitutively expressed eNOS produces low concentrations of NO, which is necessary for a good endothelial function and integrity. Endothelial derived NO is often seen as a protective agent in a variety of diseases.This review will focus on the potential protective role of eNOS. We will discuss recent data derived from studies in eNOS knockout mice and other experimental models. Furthermore, the role of eNOS in human diseases is described and possible therapeutic intervention strategies will be discussed. Copyright © 2002 John Wiley & Sons, Ltd.