bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Wiener–Hopf approximation technique for a multiple plate diffraction problem
Authors: Brannan James R. , Ervin Vincent J. , Duan Jinqiao , Razoumov Leonid 
Published: December 2003

AbstractAn approximation method is derived for the computation of the acoustic field between a series of parallel plates, subject to a time periodic incident field. The method is based on the Wiener–Hopf method of factorization, with computations involving orthogonal bases of functions that are analytic in the complex half‐plane. Copyright 2004 John Wiley & Sons, Ltd.
Index transforms associated with generalized hypergeometric functions
Authors: Yakubovich Semyon B. 
Published: December 2003

AbstractWe deal with a class of integral transformations whose kernels contain the Clausenian hypergeometric function 3F2(a1,a2,a3;b1,b2;z). These transforms are defined in terms of integrals with respect to their parameters. It involves as particular cases the familiar Olevskii and generalized Mehler–Fock transforms which are key tools in the methods of the mathematical theory of elasticity. The main theorem of boundedness of these operators as a map of L2(ℝ+)L2(ℝ+;x−1 dx) is proved. Some examples of the Olevskii and Mehler–Fock type integrals are given. Copyright © 2003 John Wiley & Sons, Ltd.
Boundary position feedback control of Kirchhoff's non‐linear strings
Authors: Kobayashi Toshihiro 
Published: December 2003

AbstractThis paper is concerned with global stabilization of an undamped non‐linear string in the case where any velocity feedback is not available. The linearized system has an infinite number of poles and zeros on the imaginary axis. In the case where any velocity feedback is not available, a parallel compensator is effective. The stabilizer is constructed for the augmented system which consists of the controlled system and a parallel compensator. It is proved that the string can be stabilized by linear boundary control. Copyright © 2003 John Wiley & Sons, Ltd.
Solution representations for a wave equation with weak dissipation
Authors: Wirth Jens 
Published: December 2003

AbstractWe consider the Cauchy problem for the weakly dissipative wave equation □v+μ/1+t
vt=0,
x∈ℝn, t≥0 parameterized by μ>0, and prove a representation theorem for its solutions using the theory of special functions.This representation is used to obtain Lp–Lq estimates for the solution and for the energy operator corresponding to this Cauchy problem.Especially for the L2 energy estimate we determine the part of the phase space which is responsible for the decay rate. It will be shown that the situation depends strongly on the value of μand that μ=2 is critical. Copyright © 2004 John Wiley & Sons, Ltd.
Single dopant diffusion in semiconductor technology
Authors: Glitzky A. , Merz W. 
Published: December 2003

AbstractThe paper deals with the analysis of pair diffusion models in semiconductor technology. The underlying model contains reaction‐drift‐diffusion equations for the mobile point defects and dopant‐defect pairs as well as reaction equations for immobile dopants which are coupled with a non‐linear Poisson equation for the chemical potential of the electrons. For homogeneous structures we present an existence and uniqueness result for strong solutions. Starting with energy estimates we derive further a priori estimates such that fixed point arguments due to Leray–Schauder guarantee the solvability of the model equations. Copyright © 2004 John Wiley & Sons, Ltd.
Approximation by herglotz wave functions
Authors: Weck Norbert 
Published: December 2003

AbstractBy a general argument, it is shown that Herglotz wave functions are dense (with respect to the C∞(Ω)‐topology) in the space of all solutions to the reduced wave equation in Ω. This is used to provide corresponding approximation results in global spaces (eg. in L2‐Sobolev‐spaces Hm(Ω)) and for boundary data. Copyright © 2004 John Wiley & Sons, Ltd.
Numerical simulation of the non‐linear crack problem with non‐penetration
Authors: Kovtunenko Victor A. 
Published: December 2003

AbstractHere the numerical simulation of some plane Lamé problem with a rectilinear crack under non‐penetration condition is presented. The corresponding solids are assumed to be isotropic and homogeneous as well as bonded. The non‐linear crack problem is formulated as a variational inequality. We use penalty iteration and the finite‐element method to calculate numerically its approximate solution. Applying analytic formulas obtained from shape sensitivity analysis, we calculate then energetic and stress characteristics of the solution, and describe the quasistatic propagation of the crack under linear loading. The results are presented in comparison with the classical, linear crack problem, when interpenetration between the crack faces may occur. Copyright © 2004 John Wiley & Sons, Ltd.
3‐D Contact problems for elastic wedges with Coulomb friction
Authors: Bach Michael , Pozharskii Dmitri 
Published: December 2003

Abstract3‐D quasi‐static contact problems for elastic wedges with Coulomb friction are reduced to integral equations and integral inequalities with unknown contact normal pressures. To obtain these equations and inequalities, Green's functions for the wedges, where one face of the wedges is either stress‐free or fixed, are needed. Using Fourier and Kontorovich–Lebedev integral transformations, all the stresses and displacements in the wedges can be constructed in terms of solutions of Fredholm integral equations of the second kind on the semiaxis. The Green's functions can be calculated as uniformly convergent power series in (1‐2ν), where νis Poisson's ratio. An exponential decay of the kernels and right‐hand sides of the Fredholm integral equations provides the applicability of the collocation method for simple and fast calculation of the Green's functions. For a half‐space, which is a special case of an elastic wedge, the kernels degenerate and the functions reduce to the well‐known Boussinesq and Cerruti solutions.Analysing the contact problems reveals that the Green's functions govern the kernels of the above mentioned integral equations and inequalities. Under the assumption that the punch has a smooth shape, the contact pressure is zero on the boundary of the unknown contact zone. Solving the contact problems with the help of the Galanov–Newton method, the normal contact pressure, the contact zone and the normal displacement around the contact zone can be determined simultaneously. In view of the numerical results, the influence of the friction forces on the punch force and the punch settlement is discussed. Copyright © 2004 John Wiley & Sons, Ltd.
On the non‐stationary Maxwellians
Authors: Gordevskyy V. D. 
Published: December 2003

AbstractThe exact Maxwell solutions of the non‐linear Boltzmann equation which have the most general form are studied. They are inhomogeneous and non‐stationary and describe rather complex motions of a rarefied gas. The classification of all possible types of these motions is obtained with a detailed analysis of the geometrical and physical features of the corresponding flows in a gas. In particular, the rotating and flying translational flows have non‐symmetric structure with two different axes: the axis of velocities and the axis of the density. The approximate description of the interaction between such flows by the bimodal distributions of a special form for the model of hard spheres is also obtained. Copyright © 2004 John Wiley & Sons, Ltd.
Messenger RNA stockpile of cyclin B, insulin‐like growth factor I, insulin‐like growth factor II, insulin‐like growth factor receptor Ib, and p53 in the rainbow trout oocyte in relation with developmental competence
Authors: Aegerter Sandrine , Jalabert Bernard , Bobe Julien 
Published: December 2003

AbstractIn the present study, correlations between the oocyte messenger RNA (mRNA) stockpile of Cyclin B, insulin‐like growth factor I (IGF‐I), insulin‐like growth factor (IGF‐II), insulin‐like growth factor receptor Ib (IGFR Ib), and p53 transcripts and the developmental competence of the oocyte were studied. For this purpose, post‐ovulatory ageing was used as a tool to generate oocytes of varying developmental competence. Mature female rainbow trout were held at 12°C and periodically checked for ovulation. Oocytes were collected from each female at ovulation and 5, 14, 21 days later. For each collected egg batch, the abundance of several mRNAs in the oocyte was analyzed by real‐time PCR and embryo development was monitored after fertilization. Egg quality was estimated not only through embryonic survival but also by studying the occurrence of specific morphological abnormalities. The present study showed that oocyte post‐ovulatory ageing was associated with variations of the relative abundance of several studied transcripts within the oocyte. In addition, the abundance of specific mRNAs could be correlated with either the embryonic survival or the occurrence of malformations. Thus, the abundance of IGFR Ib and Cyclin B transcripts in the oocyte was correlated with the occurrence of morphological abnormalities observed at yolk‐sac resorption (negatively for IGFR Ib and positively for Cyclin B), while the maternal stockpile of IGF‐I, IGF‐II, and IGFR Ib mRNAs was positively correlated with embryonic survival. Mol. Reprod. Dev. 67:127–135, 2004. © 2004 Wiley‐Liss, Inc.
Analysis of differential maternal mRNA expression in developmentally competent and incompetent bovine two‐cell embryos
Authors: Fair Trudee , Murphy Madeline , Rizos Dimitrios , Moss Catherine , Martin Finian , Boland Maurice P. , Lonergan Patrick 
Published: December 2003

AbstractThe main objective of this study was to identify mRNA transcripts associated with embryonic developmental competence. In cattle, mRNA transcripts, ribosomes, and proteins accumulated during the growth phase are drawn on to sustain maturation, fertilization, and the initial cell cycle divisions up to the 8‐ to 16‐cell stage. Early cleaving mammalian zygotes are more likely to develop to the blastocyst stage than their later cleaving counterparts, thus reflecting the intrinsic quality of the oocytes from which they originated. We describe the combination of this well‐established model for the retrospective determination of developmental competence in mammalian oocytes with a technique for wide screening of differential gene expression in different biological populations. Immature cumulus oocyte complexes were recovered from surface visible follicles on abattoir ovaries, washed, and submitted to routine in vitro maturation and fertilization. Two‐cell embryos were removed from culture at 3‐hr intervals from 24 to 42 hr post insemination (pi). Two populations of two‐cell embryos were identified; those that cleaved early (before 27 hpi) and those that cleaved late (after 33 hpi). Suppressive subtractive hybridization was carried out on cDNA from the two populations, following which, differentially expressed amplicons were subcloned and sequenced. The sequences were submitted to the nonredundant and expressed sequence tag (EST) databases at NCBI using the BLAST algorithm. The differential expression of three selected candidate genes that were identified as putatively upregulated in the early cleaving zygotes were chosen for further investigations; histone H3, cyclin B1, and GDF‐9B. Using quantitative real time PCR we have shown that histone H3A is significantly more abundant in embryos that cleave earliest. Mol. Reprod. Dev. 67:136–144, 2004. © 2004 Wiley‐Liss, Inc.
Expression and localization of fibroblast growth factor (FGF) family members during the final growth of bovine ovarian follicles
Authors: Berisha Bajram , Sinowatz Fred , Schams Dieter 
Published: December 2003

AbstractThe aim of this study was to investigate the possible participation of fibroblast growth factor (FGF) family members: FGF1, FGF2, and FGF7, and their receptor variants: FGFR, FGFR2IIIb, and FGFR2IIIc in theca interna (TI) and granulosa cell (GC) compartments of bovine follicles during final growth. A classification of follicles into five groups (<0.5; >0.5–5; >5–20; >20–180; >180 ng/ml, respectively) was performed according to the follicular fluid (FF) oestradiol‐17β (E) content. The mRNA expression and protein localization was analyzed by reverse transcription‐polymerase chain reaction (RT‐PCR) and immunohistochemistry. FGF1 mRNA expression was relatively high in TI and lower in GC, and without any regulatory change for both tissue compartments during final follicular growth. The FGF1 protein could be predominantly localized in the cytoplasm of GC, in smooth muscle cells of blood vessels, in the rete ovarii, and at a lesser degree in theca cells. FGF2 mRNA in TI increased significantly in large follicles and was low and without any regulatory change in GC. FGF7 mRNA expression was relatively high in TI and very low in GC. For FGF7 in mature follicles a marked staining of the TI and the basal layers of the GC could be demonstrated. The mRNA signal for the FGFR in TI increased significantly with beginning of E production (E > 0.5–5 ng/ml FF) and was without any regulatory change in GC. The mRNA expression of FGFR2IIIb was relatively high in GC and increased significantly during final growth of follicles in contrast to the TI with very low expression. The FGFR2IIIc mRNA expression in TI and GC was relatively high but without any clear change. Our results suggest that FGF growth factor family members are involved in process of folliculogenesis and especially during final growth of the preovulatory (dominant) follicle by stimulation of angiogenesis and GC survival and proliferation. Mol. Reprod. Dev. 67:162–171, 2004. © 2004 Wiley‐Liss, Inc.
Inhibition of bovine sperm–oocyte fusion by the p‐aminophenyl derivative of d‐mannose
Authors: Tanghe Sofie , Van Soom A. , Duchateau L. , de Kruif A. 
Published: December 2003

AbstractSeveral steps in the process of mammalian fertilization are mediated by carbohydrates. This study investigated the role of the p‐aminophenyl derivative of d‐mannose (APMP) during bovine fertilization. Inseminating cumulus–oocyte complexes (COCs) in the presence of increasing APMP concentrations resulted in a significant dose‐dependent decrease of the fertilization rate (P < 0.05). No negative effect of 50 mM APMP on total sperm motility and progressive motility was found. Subsequently, the fertilization steps at which this blocking effect could be exerted were investigated, i.e., sperm penetration of the cumulus oophorus, sperm‐zona binding, acrosome reaction, sperm–oolemma binding, and/or sperm–oocyte fusion. Inseminating cumulus‐enclosed and cumulus‐denuded oocytes in the presence of 50 mM APMP significantly decreased the fertilization rate to a comparable minimum level (P < 0.05). There was no significant relationship between the number of spermatozoa bound to the zona pellucida and the APMP concentration, and APMP nor d‐mannosylated bovine serum albumin (BSA) suppressed or stimulated sperm acrosomal status. Inseminating zona‐free oocytes in the presence of 50 mM APMP did not influence sperm–oolemma binding, but significantly inhibited sperm–oocyte fusion (P < 0.05). Preincubating zona‐free oocytes with 200 μg/ml Con A but not with 50 mM APMP inhibited the sperm–oocyte fusion rate to the same extent as when the gametes were simultaneously exposed to 50 mM APMP. These data indicate that the blocking effect of APMP on bovine fertilization is mainly due to an inhibition of sperm–oocyte fusion, probably by specific obstruction of the sperm receptor sites that are responsible for the fusion process. Mol. Reprod. Dev. 67:224–232, 2004. © 2004 Wiley‐Liss, Inc.
Vitrification of pronuclear‐stage mouse embryos on solid surface (SSV) versus in cryotube: Comparison of the effect of equilibration time and different sugars in the vitrification solution
Authors: Bagis H. , Sagirkaya H. , Mercan H. Odaman , Dinnyès A. 
Published: December 2003

AbstractThe cryopreservation of pronuclear‐stage embryos has particular importance in transgenic technology and human assisted reproductive technology (ART). The objective of this study was to improve the efficiency of cryopreservation of pronuclear‐stage mouse embryos. Two vitrification methods (solid surface vitrification (SSV) vs. vitrification in cryotube) have been compared with special emphasis on the effect of the exposure of the embryos to the solutions for various times and the sugar content (trehalose, sucrose, or raffinose) of the vitrification solutions. Pronuclear‐stage embryos were either exposed to 1 M dimethyl sulfoxide (DMSO) + 1 M propylene‐glycol (PG) solution for 2, 5, 10, or 15 min or not exposed to this “equilibration” solution. The vitrification solutions consisted of 2.75 M DMSO and 2.75 M PG in M2 medium supplemented with 1 M trehalose (DPT), 1 M sucrose (DPS), or 1 M raffinose (DPR). In the cryotube method, groups of 15–25 embryos were transferred into a 1.8 ml cryotube containing 30 μl of DPT, DPS, or DPR. After 30 sec, the cryotubes were directly plunged into liquid nitrogen (LN2) and stored for 1 day to 1 month. Vitrified samples were warmed by immersing the cryotubes in a 40°C water bath and then immediately diluted with 300 μl of 0.3 M trehalose, sucrose, or raffinose in M2. In the SSV method, after equilibration 15–20 embryos were exposed to DPT, DPS, or DPR solutions for around 20 sec before being dropped in 2‐μl drops onto a pre‐cooled (−150 to −180°C) metal surface. Vitrified droplets were stored in cryovials in LN2. Warming was performed by transferring the vitrified droplets into 0.3 M solutions of trehalose, sucrose, or raffinose at 37°C, respectively. Results showed that both SSV and cryotube vitrification methods can result in high rates of in vitro blastocyst development (up to 58.3 and 68.5% with DPR, respectively), not statistically different from that of the controls (58.3 and 64.4%). Even without the equilibration step prior to vitrification, relatively high‐survival rates have been achieved, except for the DPS solution. In conclusion, vitrification of pronuclear‐stage mouse embryos can result in high rates of in vitro development to blastocyst, and the use of raffinose in the vitrification solution is advantageous to improve cryosurvival. Mol. Reprod. Dev. 67:186–192, 2004. © 2004 Wiley‐Liss, Inc.
Improved embryo development with decreased apoptosis in blastomeres after the treatment of cloned bovine embryos with β‐mercaptoethanol and hemoglobin
Authors: Park Eul Soon , Hwang Woo Suk , Kang Sung Keun , Lee Byeong Chun , Han Jae Yong , Lim Jeong Mook 
Published: December 2003

AbstractIn preliminary experiments, the treatment of donor somatic cells with β‐mercaptoethanol (ME) or hemoglobin (Hb) improved in vitro‐development of bovine cloned embryos. This study was subsequently evaluated whether the exposure to Hb and/or ME during in vitro‐maturation or embryo culture could further promote the development of embryos cloned with ME‐treated donor cells. A prospective, randomized study was conducted and, embryo development, cell number, and apoptosis in blastocysts were monitored. A significant (P < 0.05) effect was found after the combined treatment of cloned embryos with Hb (1 μg/ml) and ME (10 μM); the development of morulae (53 vs. 35%) was greatly improved, which resulted in enhanced blastocyst formation (38%). However, cell number and apoptosis in blastocysts were predominantly affected by ME rather than Hb; a significant increase in total cell number of blastomeres (142–154 vs. 123 cells/embryo), inner cell mass (ICM) (39–41 vs. 27), and trophectoderm (TE) (103–114 vs. 98), and the ratio of ICM to TE cell number (0.26–0.27 vs. 0.22) was found. Also, the apoptosis index indicating the ratio of apoptotic cell to normal blastomere number was greatly reduced after ME treatments (0.85 vs. 0.056–0.069). When embryos cloned with ME‐treated cells were cultured in Hb + ME‐containing medium, any of the treatments to recipient oocytes before enucleation did not further promote the development. In conclusion, combined treatment of cloned embryos with Hb + ME not only improved in vitro‐development but also decreased blastomere apoptosis. The use of ME‐treated donor cells and the culture of cloned embryos in Hb + ME‐containing medium yielded the optimal results for promoting the production of blastocysts with improved quality. Mol. Reprod. Dev. 67:200–206, 2004. © 2004 Wiley‐Liss, Inc.
Embryonic development of in vitro matured and in vitro fertilized dog oocytes
Authors: Rodrigues Berenice de Ávila , Santos Lucila Carboneiro dos , Rodrigues José Luiz 
Published: December 2003

AbstractIn several studies, early cleavage stage canine embryos have been derived from in vitro fertilized oocytes cultured under various conditions. Despite these results, IVF protocols for canine oocytes have yielded low fertilization rates. In this study, Experiment I compared the effects of tissue culture medium (TCM)‐199 supplemented with either (A) 1 μg/ml estradiol or (B) 20 μg/ml estradiol + 1 μg/ml human somatotropin (hST) on the in vitro nuclear maturation rate of canine oocytes. Meiotic progression to the metaphase I and II (MI/MII) stages at 72 hr of in vitro culture (IVC) was 10.2% (11/108) in medium A versus 14.1% (30/142) in medium B (P = 0.802). In Experiment II, cleavage rate was determined among oocytes recovered from ovaries of bitches at different reproductive stages. Oocytes (n = 888) were retrieved from bitches at the follicular, anestrous, and luteal stages and selected for high morphological quality. Oocytes were matured for 48 hr in TCM‐199 supplemented with 1 μg/ml hST + 20 μg/ml estradiol. Oocytes were in vitro fertilized with fresh canine spermatozoa that had been isolated on a Percoll gradient, and were cultured in synthetic oviduct fluid (SOF) medium with bovine serum albumin (BSA; 4 mg/ml) up to 5 days in 5% CO2 in air at 37°C. A proportion of oocytes (30.6%) with identifiable nuclear material had cytoplasm penetrated or fertilized by sperm. The percentage of oocytes developing into early stage embryos was 10.1% (27/267). Although pronuclear development was observed to be higher for oocytes recovered at the follicular phase, the cleavage rate was similar among oocytes recovered from bitches at the follicular, anestrus, and luteal stages. There was no correlation between the proportion of capacitated or acrosome reacted spermatozoa and pronuclei formation and/or percent cleavage. It was concluded that TCM‐199 supplemented with 1 μg/ml hST and estradiol (20 μg/ml) supports nuclear and cytoplasmic maturation of canine oocytes. In this study, meiotic competence was verified by the in vitro production (IVP) and development of embryos up to the 8 cell‐stage. Furthermore, the results indicate that, under the described conditions and despite the influence of reproductive status of the bitch on the developmental competence of in vitro fertilized oocytes to the pronuclei stage, cleavage was independent of donor's reproductive estrous cycle stage. Mol. Reprod. Dev. 67:215–223, 2004. © 2004 Wiley‐Liss, Inc.