bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of alcohols on micellization and on the reaction methyl 4‐nitrobenzenesulfonate + Br− in cetyltrimethylammonium bromide aqueous micellar solutions
Authors: Muñoz María , del Mar Graciani María , Rodríguez Amalia , Moyá María Luisa
Published: September 2004

The effects of n‐hexanol, n‐pentanol, and n‐butanol on the critical micelle concentration (cmc), on the micellar ionization degree (α), and on the rate of the reaction methyl 4‐nitrobenzenesulfonate + Br− have been investigated in cetyltrimethylammonium bromide (CTAB) aqueous solutions. An increase in the alcohol concentration present in the solution produces a decrease in the cmc and an increase in the micellar ionization degree. Kinetic data show that the observed rate constant decreases as alcohol concentration increases. This result was rationalized by considering variations in the equilibrium binding constant of the methyl 4‐nitrobenzenesulfonate molecules to the micelles, variations in the interfacial bromide ion concentration, and variations in the characteristics of the water–alcohol bulk phase provoked by the presence of alcohols. When these operative factors are considered, kinetic data in this and other works show that the second‐order rate constants in the micellar pseudophases of water–alcohol micellar solutions are quite similar to those estimated in the absence of alcohols. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 634–641, 2004
A Study of Copolymerization of 1‐Hexene with 2,5‐Norbornadiene Using Metallocene Catalysts
Authors: Yanjarappa Mallinamadugu J. , Sivaram Swaminathan
Published: September 2004

Summary: Copolymerization of 1‐hexene with a symmetrical diene, namely 2,5‐norbornadiene was studied using four different metallocene catalysts. Copolymerization was found to occur exclusively through one of the two equally reactive endocyclic double bonds with all the four catalysts. Copolymerization results in low molecular weight oligomers with the number average molecular weight ($\overline M _{\rm n}$) varying from 1 000–3 000. End group analysis of the co‐oligomers revealed that the β‐hydrogen transfer after 2,1 insertion also occurs in the presence of highly regiospecific catalysts. The regio errors were also found to depend on various reaction parameters such as polymerization time, Al/Zr mol ratio, metallocene concentration and polymerization temperature.

Plots of variation in end groups and NBD incorporation with time.

magnified image

Plots of variation in end groups and NBD incorporation with time.
Expression pattern of the maternal factor zygote arrest 1 (Zar1) in bovine tissues, oocytes, and embryos
Authors: Brevini Tiziana A.L. , Cillo F. , Colleoni S. , Lazzari G. , Galli C. , Gandolfi F.
Published: September 2004

Zygote arrest 1 (Zar1) is an ovary‐specific maternal factor that plays an essential role during the oocyte‐to‐embryo transition in mouse. In this species, Zar1 expression is strictly limited to the oocyte, the zygote and, at a lower level, the 2‐cell embryo. Aim of the present study was to analyze the presence and the expression pattern of the Zar1 ortholog in bovine tissues and embryos. Reverse transcription (RT)‐polymerase chain reaction (PCR) analysis was performed in a panel of bovine tissues, in oocytes and pre‐implantation in vitro produced embryos. The results demonstrated that a Zar1 ortholog is present in cattle. In the adult, the gene is expressed in ovary, testis, muscle, and myocardium. The gene is also expressed in the oocyte, the zygote, and in all the stages of embryonic development until blastocyst formation. A semi‐quantitative RT‐PCR analysis revealed that Zar1 levels are constant through in vitro development with the exception of the 4‐cell stage, when a significant increase is observed. The exposure of fertilized oocytes to the RNA polymerase II inhibitor alpha‐amanitin was able to suppress this Zar1 increase indicating that transcription of this gene occurs at the 4‐cell stage. Zar1 is conserved in cattle but has an expression pattern different from the mouse. In particular, Zar1 expression in the adult is not limited to the ovary and in the embryo is expressed well beyond the oocyte to embryo transition. Moreover, the identification of Zar1 transcription at the 4‐cell stage represents the first characterization of one of the genes expressed in cattle embryos before the major onset of embryonic transcription. Mol. Reprod. Dev. 69: 375–380, 2004. © 2004 Wiley‐Liss, Inc.
Polyol pathway along the bovine epididymis
Authors: Frenette Gilles , Lessard Carl , Sullivan Robert
Published: September 2004

During the epididymal transit, male gametes acquire new surface proteins necessary for their fertilizing ability. We have previously shown that membranous vesicles, called epididymosomes, interact with sperm surface within the epididymal fluid allowing transfer of some proteins to different subcellular compartments of spermatozoa. We previously showed that one of the major proteins associated with epididymosomes was an aldose reductase (gene: AKR1B5) and confirmed that aldose reductase is located in the epithelial cells bordering the intraluminal compartment of the epididymis. The present study shows that cytosolic aldose reductase activity was maximal in the proximal and middle segments of the epididymis and decreased in the distal epididymis. Western and Northern blot analysis confirmed the distribution pattern of aldose reductase and of the encoding mRNA. The optimal pH of epididymal aldose reductase was 6.0–6.5 when glucose was used as a substrate; this corresponds to the pH of the intraluminal epididymal fluid. In order to evaluate the possible involvement of sorbitol in sperm physiology, Western blot of tissue homogenates were probed with an anti‐sorbitol dehydrogenase antibody. The amount of enzyme immunodetected was higher in the proximal and distal segments of the epididymis when compared to the amount detectable in the middle segment of the epididymis. Sorbitol dehydrogenase activity as well as the level of the encoding mRNA showed the same pattern of distribution. Furthermore, immunohistological studies using the anti‐sorbitol dehydrogenase revealed that this enzyme was synthesized by the epididymal epithelial cells bordering the intraluminal compartment. Knowing the importance of sorbitol and fructose in sperm metabolism, we hypothesized that the polyol pathway is involved in the modulation of sperm motility within the epididymis. Mol. Reprod. Dev. 69: 448–456, 2004. © 2004 Wiley‐Liss, Inc.
KIF2Aβ: A kinesin family member enriched in mouse male germ cells, interacts with translin associated factor‐X (TRAX)
Authors: Bray Jeffrey D. , Chennathukuzhi Vargheese M. , Hecht Norman B.
Published: September 2004

Translin associated factor X (TRAX) is a binding partner of TB‐RBP/Translin. A cDNA encoding the 260 C‐terminal amino acids of KIF2Aβ was isolated from mouse testis cDNAs in a yeast two‐hybrid library screen for specific TRAX‐interacting proteins. KIF2Aβ was expressed predominantly in the mouse testis and enriched in germ cells. The interaction of full‐length KIF2Aβ or its C‐terminus with TRAX was verified using in vitro synthesized fusion proteins. Deletion mapping of the TRAX‐binding region of KIF2Aβ indicated that amino acids 514–659 were necessary and sufficient for the interaction in vivo. Confocal microscopy studies using GFP‐fusion proteins demonstrated that KIF2Aβ colocalizes with TRAX in a perinuclear location. KIF2Aβ does not interact with TB‐RBP, suggesting that either TRAX can function as an adaptor molecule for motor proteins and TB‐RBP, or that this interaction reveals an undescribed role for TRAX in germ cells. The interaction with KIF2Aβ suggests a role for TRAX in microtubule‐based functions during spermatogenesis. Mol. Reprod. Dev. 69: 387–396, 2004. © 2004 Wiley‐Liss, Inc.
Several signaling pathways are involved in the control of cattle oocyte maturation
Authors: Vigneron Céline , Perreau Christine , Dupont Joélle , Uzbekova Svetlana , Prigent Claude , Mermillod Pascal
Published: September 2004

The main limit of in vitro production of domestic mammal embryos comes from the low capacity of in vitro matured oocytes to develop after fertilization. As soon as they are separated from follicular environment, oocytes spontaneously resume meiosis without completion of their terminal differentiation. Roscovitine (ROS), an inhibitor of M‐phase promoting factor (MPF) kinase activity reversibly blocks the meiotic resumption in vitro. However, in cattle maturing oocytes several cellular events such as protein synthesis and phosphorylation, chromatin condensation and nuclear envelope folding escape ROS inhibition suggesting the alternative pathways in oocyte maturation. We compared the level of synthesis and phosphorylation of several protein kinases during bovine cumulus oocyte complex (COC) maturation in vitro in the presence or not of epidermal growth factor (EGF) and ROS. We showed that during the EGF‐stimulated maturation, ROS neither affected the decrease of EGF receptor (EGFR) nor did inhibit totally its phosphorylation in cumulus cells and also did not totally eliminate tyrosine phosphorylation in oocytes. However, ROS did inhibit the Phosphoinositide 3‐kinase (PI3) activity when oocytes mature without EGF. Accumulation of Akt/PKB (protein kinase B), JNK1/2 (jun N‐terminal kinases) and Aurora‐A in oocytes during maturation was not affected by ROS. However, the phosphorylation of Akt but not JNKs was diminished in ROS‐treated oocytes. Thus, PI3 kinase/Akt, JNK1/2 and Aurora‐A are likely to be involved in the regulation of bovine oocyte maturation and some of these pathways seem to be independent to MPF activity and meiotic resumption. This complex regulation may explain the partial meiotic arrest of ROS‐treated oocytes and the accelerated maturation observed after such treatment. Mol. Reprod. Dev. 69: 466–474, 2004. © 2004 Wiley‐Liss, Inc.
Immunolocalization of cubilin, megalin, apolipoprotein J, and apolipoprotein A‐I in the uterus and oviduct
Authors: Argraves W. Scott , Morales Carlos R.
Published: September 2004

Spermatozoa maturation and capacitation occurring in the male and female reproductive tracts, respectively, involves the remodeling of the spermatozoa plasma membrane. Apolipoprotein J (apoJ) and apolipoprotein A‐I (apoA‐I) have been implicated in the process of lipid exchange from the spermatozoa plasma membrane to epithelial cells lining the male reproductive tract. Evidence suggests that this process is mediated by the cooperative action of the endocytic lipoprotein receptors megalin and cubilin, which are expressed at the apical surface of absorptive epithelia in various tissues, including the efferent ducts and epididymis. Here, we investigated the possibility that these receptors and their lipid‐binding ligands, apoJ and apoA‐I, might function similarly in the female reproductive tract. We show that megalin and cubilin are expressed in the uterine epithelium at all stages of the estrous cycle, maximally during estrous and metestrous stages. In the oviduct, there is pronounced expression of both megalin and cubilin in the nonciliated cells of the proximal oviduct and epithelial cells of the distal oviduct, particularly during estrous and metestrous stages. In both uterine and oviduct epithelial cells, megalin and cubilin were located on the apical regions of the cells, consistent with a distribution at the cell surface and in endosomes. ApoJ and apoA‐I were both detected in apical regions of uterine and oviduct epithelial cells. Secretory cells of the uterine glands were found to express apoJ and apoA‐I suggesting that the glands are a site of synthesis for both proteins. In summary, our findings indicate that megalin and cubilin function within the female reproductive tract, possibly mediating uterine and oviduct epithelial cell endocytosis of apoJ/apoA‐I‐lipid complexes and thus playing a role in lipid efflux from the sperm plasma membrane, a major initiator of capacitation. Mol. Reprod. Dev. 69: 419–427, 2004. © 2004 Wiley‐Liss, Inc.
Implication of cAMP during porcine sperm capacitation and protein tyrosine phosphorylation
Authors: Tardif Steve , Lefièvre Linda , Gagnon Claude , Bailey Janice L.
Published: September 2004

Second messengers are involved in sperm fertilizing potential, as both motility and the acrosome reaction are influenced by cAMP. Moreover, the activity of cyclic nucleotides is implicated in the appearance of tyrosine phosphorylated sperm proteins, which is associated with capacitation in the mammalian spermatozoa. Nevertheless, the involvement of the cAMP/protein kinase A (PK‐A) pathway during pig sperm capacitation may be different from that observed in other mammals. The objective of the present study was to clarify the cAMP/PK‐A pathway during the capacitation of porcine spermatozoa and to evaluate this impact on the p32 sperm tyrosine phosphoprotein appearance. The presence of p32 was assessed after incubating fresh pig sperm with IBMX/db‐cAMP, H‐89, a PK‐A inhibitor or bistyrphostin, a tyrosine kinase inhibitor, in capacitating (CM) or non‐capacitating conditions (NCM) by immunoblotting SDS‐extracted and separated sperm proteins using an anti‐phosphotyrosine antibody. When pig spermatozoa were incubated in CM supplemented with H‐89 (50 μM) or bistyrphostin (1.2 μM), capacitation decreased significantly (P < 0.001). The p32 sperm tyrosine phosphoprotein, previously shown to be associated with capacitation of porcine sperm though not necessarily an end point of this phenomenon, was not modulated by IBMX/db‐cAMP (100 μM/1 mM), H‐89 (50 μM) nor bistyrphostin (1.2 μM). Our results indicate, therefore, that pig sperm are regulated somewhat differently than as described for other mammals, because although the cAMP/PK‐A and tyrosine kinase pathways are involved in capacitation, they do not influence the appearance of p32. Mol. Reprod. Dev. 69: 428–435, 2004. © 2004 Wiley‐Liss, Inc.
Oocyte‐selective expression of MT transposon‐like element, clone MTi7 and its role in oocyte maturation and embryo development
Authors: Park Chang‐Eun , Shin Mi‐Ra , Jeon Eun‐Hyun , Lee Sook‐Hwan , Cha Kwang‐Yul , Kim Kyungjin , Kim Nam‐Hyung , Lee Kyung‐Ah
Published: September 2004

Previously, we found MT transposon‐like element, clone MTi7 (MTi7) is highly expressed in the mouse ovary. Here, we show that the MTi7 is expressed in the oocyte from the primordial to the preovulatory follicles. For RNA interference (RNAi), double stranded RNAs (dsRNAs) were prepared for MTi7 and c‐mos, a control gene with known functions. Each dsRNA was microinjected into germinal vesicle (GV) stage oocytes or zygotes with pronuclei (PN), after which developmental changes, mRNA expression, and nuclear and microtubular organization were analyzed. We found a 43.4–53% GV arrest in the microinjected oocytes with a concomitant decrease in targeted mRNA expression. In MTi7 dsRNA‐injected early and late PN zygotes, a 92.9% 1‐cell arrest and 76.9% 2‐cell arrest were observed, respectively. This is the first report of an oocyte‐selective expression of MTi7 mRNA, and our results strongly suggest that MTi7 involved in the nuclear membrane breakdown during oocyte maturation and embryo development. Mol. Reprod. Dev. 69: 365–374, 2004. © 2004 Wiley‐Liss, Inc.
Association of female aging with decreased parthenogenetic activation, raised MPF, and MAPKs activities and reduced levels of glutathione S‐transferases activity and thiols in mouse oocytes
Authors: Tarín Juan J. , Gómez‐Piquer Vanessa , Pertusa José F. , Hermenegildo Carlos , Cano Antonio
Published: September 2004

This study aims to determine in the mouse whether oocytes from reproductively old females exhibit a different susceptibility to be parthenogenetically activated when compared to oocytes from young females. At the age of 10–12 (young‐female group) or 60–62 (old‐female group) weeks, hybrid female mice were superovulated using pregnant mare's serum gonadotropin (PMSG) followed by human chorionic gonadotropin (hCG) 48 hr later. After removing the cumulus cells, oocytes were exposed to any of two different activating protocols: (a) 6‐min exposure to 8% ethanol; and (b) treatment with 200 μM thimerosal for 15 min followed by 8 mM dithiothreitol (DTT) for 30 min. Oocytes from old female mice displayed (1) lower total percentage of parthenogenetic activation and extrusion of the second polar body after treatment with either thimerosal + DTT or ethanol; (2) higher M‐phase‐promoting factor (MPF) and mitogen‐activated protein kinases (MAPKs) activities; and (3) lower intracytoplasmic levels of glutathione S‐transferases (GSTs) activity and thiols than oocytes from young females. These data show that female aging is associated with higher resistance of oocytes to be parthenogenetically activated, higher MPF and MAPKs activities and lower intracytoplasmic levels of GSTs activity and thiols. Mol. Reprod. Dev. 69: 402–410, 2004. © 2004 Wiley‐Liss, Inc.
On the uncapacitated K‐commodity network design problem with zero flow‐costs
Authors: Ng Ada Suk‐fung , Sastry Trilochan , Leung Janny M.Y. , Cai X.Q.
Published: September 2004

Extending Sastry's result on the uncapacitated two‐commodity network design problem, we completely characterize the optimal solution of the uncapacitated K‐commodity network design problem with zero flow costs for the case when K = 3. By solving a set of shortest‐path problems on related graphs, we show that the optimal solutions can be found in O(n3) time when K = 3, where n is the number of nodes in the network. The algorithm depends on identifying a list of “basic patterns”; the number of basic patterns grows exponentially with K. We also show that the uncapacitated K‐commodity network design problem can be solved in O(n3) time for general K if K is fixed; otherwise, the time for solving the problem is exponential. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004
Inverse Toeplitz preconditioners for Hermitian Toeplitz systems
Authors: Lin Fu‐Rong , Ching Wai‐Ki
Published: September 2004

In this paper we consider solving Hermitian Toeplitz systems Tnx=b by using the preconditioned conjugate gradient (PCG) method. Here the Toeplitz matrices Tn are assumed to be generated by a non‐negative continuous 2π‐periodic function ƒ, i.e. Tn=𝒯n[ƒ]. It was proved in (Linear Algebra Appl. 1993; 190:181) that if ƒ is positive then the spectrum of 𝒯n[1/ƒ]𝒯n[ƒ] is clustered around 1. We prove that the trigonometric polynomial q (s⩾2, cf. (2) and (3)) converges to 1/ƒ uniformly as n→∞ under the condition that 1/ƒ is in Wiener class. It follows that the computational cost of the PCG method can be reduced by replacing 1/ƒ with q, where N<n. We also extend our method to construct efficient preconditioners for Tn when ƒ has finite zeros of even orders. We prove that with our preconditioners, the preconditioned matrix has spectrum clustered around 1. It follows that the PCG methods converge very fast when applied to solve the preconditioned systems. Numerical results are given to demonstrate the efficiency of our preconditioners. Copyright © 2004 John Wiley & Sons, Ltd.
A preconditioning proposal for ill‐conditioned Hermitian two‐level Toeplitz systems
Authors: Noutsos D. , Capizzano S. Serra , Vassalos P.
Published: September 2004

Large 2‐level Toeplitz systems arise in many applications and thus an efficient strategy for their solution is often needed. The already known methods require the explicit knowledge of the generating function ƒ of the considered system Tnm(ƒ)x=b, an assumption that usually is not fulfilled in real applications. In this paper, we extend to the 2‐level case a technique proposed in the literature in such a way that, from the knowledge of the coefficients of Tnm(ƒ), we determine optimal preconditioning strategies for the solution of our systems. More precisely, we propose and analyse an algorithm for the economical computation of minimal features of ƒ that allow us to select optimal preconditioners. Finally, we perform various numerical experiments which fully confirm the effectiveness of the proposed idea. Copyright © 2004 John Wiley & Sons, Ltd.
The perturbation bounds for eigenvalues of normal matrices
Authors: Li Wen , Sun Weiwei
Published: September 2004

In this paper we present some new absolute and relative perturbation bounds of eigenvalues of normal matrices. The bounds depend upon the closeness of perturbed matrices to normal matrices and improve those previous results (Duke Math. J. 1953; 20:37–39, Linear Algebra Appl. 1996; 246:215–223). Copyright © 2004 John Wiley & Sons, Ltd.
Structured condition numbers of large Toeplitz matrices are rarely better than usual condition numbers
Authors: Böttcher A. , Grudsky S. M.
Published: September 2004

When working with structured matrices, structured condition numbers are more meaningful than usual condition numbers. The usual condition numbers of Toeplitz matrices may grow exponentially with the dimension of the matrix. The purpose of this note is to show that in this case the structured condition numbers do with high probability also increase exponentially, which supports the claim that one is not likely to win much on the average Toeplitz input by passing from the usual condition numbers of Toeplitz matrices to their structured counterparts. Copyright © 2004 John Wiley & Sons, Ltd.
Tikhonov regularization of large symmetric problems
Authors: Calvetti D. , Reichel L. , Shuibi A.
Published: September 2004

Many popular solution methods for large discrete ill‐posed problems are based on Tikhonov regularization and compute a partial Lanczos bidiagonalization of the matrix. The computational effort required by these methods is not reduced significantly when the matrix of the discrete ill‐posed problem, rather than being a general nonsymmetric matrix, is symmetric and possibly indefinite. This paper describes new methods, based on partial Lanczos tridiagonalization of the matrix, that exploit symmetry. Computed examples illustrate that one of these methods can require significantly less computational work than available structure‐ignoring schemes. Copyright © 2004 John Wiley & Sons, Ltd.
Stewart's pivoted QLP decomposition for low‐rank matrices
Authors: Huckaby D. A. , Chan T. F.
Published: September 2004

The pivoted QLP decomposition, introduced by Stewart, represents the first two steps in an algorithm which approximates the SVD. If A is an m‐by‐n matrix, the matrix A∏0 is first factored as A∏0 = QR, and then the matrix RT∏1 is factored as RT∏1 = PLT, resulting in A = Q∏1LPT∏, with Q and P orthogonal, L lower‐triangular, and ∏0 and ∏1 permutation matrices. The Q and P matrices provide approximations of the left and right singular subspaces, and the diagonal elements of L are excellent approximations of the singular values of A. Stewart observed that pivoting is not necessary in the second step, allowing one to efficiently truncate the decomposition, computing only the first few columns of R and L and choosing the stopping point dynamically. In this paper, we demonstrate that this truncating actually works by extending our theory for the complete pivoted QLP decomposition (UCLA CAM Report # 02‐29, 2002). In particular, say there is a gap between σk and σk+1, and partition the matrix L into diagonal blocks L11 and L22 and off‐diagonal block L21, where L11 is k‐by‐k. If we compute only the block L11, the convergence of (σj(L11)−1 − σ)/σ for j = 1,…,k are all quadratic in the gap ratio σk+1/σk. Hence, if the gap ratio is small, as it usually is when A has numerical rank k (independent of m and n), then all of the singular values are likely to be well approximated. This truncated pivoted QLP decomposition can be computed in 𝒪(mnk) time, making it ideal for accurate SVD approximations of low‐rank matrices. Copyright © 2004 John Wiley & Sons, Ltd.
Linear eigenvalue analysis of the disc‐brake squeal problem
Authors: Cao Q. , Ouyang H. , Friswell M. I. , Mottershead J. E.
Published: September 2004

This paper presents a numerical method to calculate the unstable frequencies of a car disc brake and suggests a suitable analysis procedure. The stationary components of the disc brake are modelled using finite elements and the disc as a thin plate. The separate treatments of the stationary components and the rotating disc facilitate the modelling of the disc brake squeal as a moving load problem. Some uncertain system parameters of the stationary components and the disc are tuned to fit experimental results. A linear, complex‐valued, asymmetric eigenvalue formulation is derived for the friction‐induced vibration of the disc brake. Predicted unstable frequencies are compared with experimentally established squeal frequencies of a real car disc brake. Copyright © 2004 John Wiley & Sons, Ltd.
A method for multiple crack growth in brittle materials without remeshing
Authors: Budyn É. , Zi G. , Moës N. , Belytschko T.
Published: September 2004

A method for modelling the growth of multiple cracks in linear elastic media is presented. Both homogeneous and inhomogeneous materials are considered. The method uses the extended finite element method for arbitrary discontinuities and does not require remeshing as the cracks grow; the method also treats the junction of cracks. The crack geometries are arbitrary with respect to the mesh and are described by vector level sets. The overall response of the structure is obtained until complete failure. A stability analysis of competitive cracks tips is performed. The method is applied to bodies in plane strain or plane stress and to unit cells with 2–10 growing cracks (although the method does not limit the number of cracks). It is shown to be efficient and accurate for crack coalescence and percolation problems. Copyright © 2004 John Wiley & Sons, Ltd.
Smoothing with positivity‐preserving Padé schemes for parabolic problems with nonsmooth data
Authors: Wade B. A. , Khaliq A. Q. M. , Siddique M. , Yousuf M.
Published: September 2004

We introduce a new class of higher order numerical schemes for parabolic partial differential equations that are more robust than the well‐known Rannacher schemes. The new family of algorithms utilizes diagonal Padé schemes combined with positivity‐preserving Padé schemes instead of first subdiagonal Padé schemes. We utilize a partial fraction decomposition to address problems with accuracy and computational efficiency in solving the higher order methods and to implement the algorithms in parallel. Optimal order convergence for nonsmooth data is proved for the case of a self‐adjoint operator in Hilbert space as well as in Banach space for the general case. Numerical experiments support the theorems, including examples in pricing options with nonsmooth payoff in financial mathematics. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2005
Providing psychosocial support for breast cancer patients based on screening for distress within a consultation‐liaison service
Authors: Söllner Wolfgang , Maislinger Susanne , König Alexandra , DeVries Alexander , Lukas Peter
Published: September 2004

In a consecutive sample of 100 breast cancer patients undergoing radiotherapy, cancer‐related distress was assessed with the Hospital Anxiety and Depression Scale and patients' interest in and acceptance of psychosocial support with the Questionnaire for Psychosocial Support and the European Consultation Liaison Workgroup documentation form. 31% of the patients suffered moderate to severe anxiety and/or depression and 42% expressed interest in supportive counselling. The wish for psychosocial support did not correlate with distress (moderate or severe anxiety and/or depression; Kappa = 0.06; P = 0.560). Patients with elevated levels of distress and/or those expressing a wish for psychosocial support were offered counselling by a psychotherapist and a social worker within the framework of a liaison service; 69% of the 58 patients offered such support accepted it. We conclude that screening instruments are helpful in identifying and consequently offering support to patients in need of counselling. Copyright © 2004 John Wiley & Sons, Ltd.
Vorsicht Hochspannung!: Risikomanagement in Energiemärkten (Teil III) Fortgeschrittene Spotpreismodelle und VaR‐Ansätze
Authors: Rachev Svetlozar (Zari)
Published: September 2004

Im ersten Teil der Serie [siehe RISKNEWS 03/2004] wurde eine kurze Einführung in den Stromhandel in Deutschland gegeben. Weiterhin wurden Besonderheiten im Preisverhalten auf Strommärkten erläutert. Der zweite Teil [siehe RISKNEWS 04/2004] beschäftigte sich mit der Modellierung von Strompreisen, insbesondere der Berücksichtigung von Saisonalitäten sowie der stochastischen Modellierung der Preisprozesse. Der dritte Teil der Serie erläutert verfeinerte Methoden der Preismodellierung sowie Ansätze des Risikomanagements in Energiemärkten mit Hilfe des Value‐at‐Risk und RAROC‐Konzepts.
Health related quality of life of adolescents in Vietnam: cross‐cultural adaptation and validation of the Adolescent Duke Health Profile
Authors: Thi Xuan Hanh Vo , Guillemin Francis , Dinh Cong Duong , Parkerson George R. , Bach Thu Pham , Tu Quynh Pham , Briançon Serge
Published: September 2004

Quality of life (QOL) of adolescents has been scarcely documented in a general population sample. The study was aimed at translating and adapting the Adolescent Duke Health Profile to Vietnamese, validating the questionnaire, determining reference value, and identifying determinants of poor QOL.

Following a cross‐cultural methodology, the Adolescent Duke Health Profile (ADHP) had content adapted to Vietnamese by alteration of 2 out of 17 items. Test–retest validity was checked in 408 adolescents. Construct validity and internal consistency were assessed in a 1408 probability sample of adolescents in Vietnam, and determinants were analysed by multiple linear regression.

The ADHP showed satisfactory internal consistency (Cronbach's α=0.87–0.92) and satisfactory construct validity in relation with drug abuse or not, or with parent situation living in couple or alone. Test–retest reliability was acceptable (ICC=0.7–0.8) and major determinants were age, sex, education, chronic disease, alcohol and drug use.

This works provide a validated, simple health related QOL scale suited to adolescent population with reference values. Taking into account determinants identified will help program prevention and intervention health policy and to evaluate the effect of these actions.
Expression and regulation of interleukin‐23 subunits in human peripheral blood mononuclear cells and hematopoietic cell lines in response to various inducers
Authors: Ma Xiao‐Tong , Zhang Xiu‐Jun , Zhang Bin , Geng Yi‐Qi , Lin Yong‐Min , Li Ge , Wu Ke‐Fu
Published: September 2004

IL‐23 is a novel cytokine composed of an IL‐12 p40 and a p19 subunit. We analyzed human peripheral blood mononuclear cells (PBMC) and hematopoietic cell lines for constitutive expression of IL‐23 and IL‐12 subunits and expression following exposure to various stimuli, and investigated the mechanisms of their induction by LPS and SAC. IL‐23 p19 and IL‐12 p35 mRNAs were expressed in fresh PBMC, and expression of all IL‐23 and IL‐12 subunits was up‐regulated by LPS and SAC. LPS‐induced increase of IL‐23 and IL‐12 subunits expression was CD14‐dependent, while CD14 was not involved in SAC‐induced p19 transcription. Both LPS‐ and SAC‐induced subunits expression required p38 MAPK pathway. PHA effected an increase of p19 mRNA in both CD4+ and CD8+ T cells, whereas p35 was minimally regulated by PHA. IFN‐γ primed monocytes for LPS stimulation of p19, p35 and p40 expression. p19 mRNA was detectable in most hematopoietic cell lines tested but p35 distribution was more restricted. A phorbol diester enhanced p19, p35 and p40 expression in EBV‐positive cell lines. Our results suggest that both the subunits of IL‐23 are tightly regulated; the expression pattern and regulation mode of IL‐23 p19 is similar to as well as distinct from that of IL‐12 p35.
A ‘Secret Society’? The Internal and External Relations of the Kinship in Husbandry, 1941–52
Authors: MOORE-COLYER RICHARD , CONFORD PHILIP
Published: September 2004

First meeting in September 1941, the Kinship in Husbandry was a group of twelve men concerned for the future of English rural life in the post-war world and determined to communicate their vision of a revitalised countryside. Central to this vision were an agriculture based on organic principles and a rural culture which would encourage craftsmanship while drawing spiritual sustenance from a Christianity reconnected with nature. This paper traces the Kinship's origins in the pre-war activities of Gerard Wallop (Viscount Lymington) and Rolf Gardiner, and examines the names of those considered by the original twelve as possible associates. Archival evidence indicates tensions between Kinsmen over the group's strategy and the extent to which it should cooperate with other bodies. In particular, correspondance shows that H. J. Massingham was deeply unhappy about Gardiner's pro-German sympathies and mistrusted the influence within the Kinship of Gardiner and his fellow landowners Wallop and Lord Northbourne, who appear to have formed an inner circle. The article concludes by considering briefly the extent to which the Kinship succeeded in spreading its ideas, and suggests that, despite its failure to influence post-war developments, its longer-term impact can be seen in the current public interest in organic food and farming.
‘Policy on the Hoof’: Sir Robert Peel, Sir Edward Knatchbull and the Trial of the Elham Machine Breakers, 1830
Authors: GRIFFIN CARL J.
Published: September 2004

On 22nd October 1830 Sir Edward Knatchbull passed sentence on seven men for threshing-machine breaking in the Elham Valley area of East Kent. The four day sentence enraged both local farmers and Home Secretary Peel alike, and was seized upon by other labourers and artisans hostile to threshing-machines who believed that Knatchbull had legitimised such acts of rural Luddism. The trial sparked an intensification of ‘Swing’ in East Kent and for the first time acts of overt protest beyond. Knatchbull, upon being pressed by George Maule, the Treasury Solicitor, admitted that the sentences could not have been otherwise under circumstances he was not at liberty to disclose. This paper examines these circumstances and uncovers a bizarre chain of events which shed new light on both the genesis of ‘Swing’ and also upon local-central government relations regarding policy implementation and creation.
Extreme Depopulation in the Spanish Rural Mountain Areas: A Case Study of Aragon in the Nineteenth and Twentieth Centuries
Authors: COLLANTES FERNANDO , PINILLA VICENTE
Published: September 2004

The phenomenon of rural depopulation has been an intense and centuries-long process in the mountain areas of Aragon in Spain. Throughout the nineteenth century, the traditional economic model of these territories broke down due to the crisis suffered by seasonal sheep migration, the non-viability of the old forms of agricultural production based on self-sufficiency and the destruction of the scattered textile industry. The new scenario offered some possible alternatives in sectors such as livestock, timber, mining and energy production or the activities associated with tourism and second homes. However, it is only these latter activities that have demonstrated some capacity to alter significantly the demographic tendencies, and even then they have done so in a somewhat delayed fashion and in a way limited to a small proportion of the geographical areas under study.
The Scott Report and the Labour Party: The Protection of the Countryside during the Second World War
Authors: TICHELAR MICHAEL
Published: September 2004

The article will seek to plot the position of the Labour Party in relation to debates during the Second World War between rural preservationists and agricultural modernisers. It will review the recommendations of the Scott Report into land utilisation in rural areas, and outline recent research into popular attitudes to the countryside. It will then describe the way the Labour Party responded to these developments and draw some longer-term conclusions about their significance in relation to current debates about national identity and the countryside. It will be argued that while the Labour Party supported the need to protect the look of the landscape as part of the nation's heritage and national identity, in line with public opinion at the time, it also sought to encourage the physical planning of both town and country in a way that rejected some of the more anti-metropolitan tendencies of the rural preservationists.
Validität des Heidelberger Vorschulscreenings zur auditiv-kinästhetischen Wahrnehmung und Sprachverarbeitung
Authors: Troost Judith , Brunner Monika , Pröschel Ute
Published: September 2004

Zusammenfassung. Mit dem Heidelberger Vorschulscreening (HVS) zur auditiv-kinästhetischen Wahrnehmung und Sprachverarbeitung von Brunner et al. (2001) liegt ein Testverfahren vor, das sprachanalytische und artikulatorische Fähigkeiten im Vorschulalter erfasst. Ziel der Studie war die Beurteilung der Validität des HVS. Die Stichprobe der vorliegenden Untersuchung umfasst 103 Kinder, welche als Vorschulkinder zur Normstichprobe des HVS gehörten und ca. zwei Jahre später, Mitte der zweiten Klasse, Lese-, Rechtschreib- und Intelligenztests bearbeiteten. Der HVS-Gesamtwert und 6 der 7 Untertests zeigten statistisch bedeutsame, vom Vorzeichen her erwartungsgemäße und numerisch im unteren bis mittleren Bereich liegende Korrelationen mit der Lese- und Rechtschreibleistung. Die Korrelationen mit der sprachfreien Intelligenz waren im Vergleich dazu seltener signifikant und durchschnittlich niedriger. Das HVS prüft auf ökonomische Weise Fähigkeiten, deren Einschränkung ein Risiko für den Schriftspracherwerb darstellt.
An evaluation of processes regulating spatial and temporal patterns in lake sulfate in the Adirondack region of New York
Authors: Chen Limin , Driscoll Charles T.
Published: September 2004

As a result of the Clean Air Act Amendments of 1970 and 1990, there have been significant decreases in sulfate (SO42−) concentrations in surface waters across the northeastern United States. The 37 Direct/Delayed Response Program (DDRP) watersheds in the Adirondacks receive elevated levels of atmospheric S deposition and showed considerable variability in lake SO42− concentrations. In response to decreases in atmospheric S deposition, these sites have generally exhibited relatively uniform decreases in surface water SO42− concentrations. In this study, an integrated biogeochemical model (PnET‐BGC) was used to simulate the response of lake SO42− concentrations at these DDRP sites to recent changes in atmospheric S deposition. Using default parameters and algorithms, the model underpredicted lake SO42− concentrations at sites with high SO42− concentrations and overpredicted at sites with low SO42− concentrations. Initial predictions of lake SO42− were relatively uniform across the region. Initial model simulations also underpredicted decreases in lake SO42− concentrations from 1984 to 2001. We identified seven hypotheses that might explain the discrepancies between model predictions and the measured data. Model inputs, parameters, and algorithms were modified to help test these hypotheses and better understand factors that control spatial and temporal patterns in lake SO42− in this acid‐sensitive region.
Magnetization of the plasma sheet
Authors: Kaufmann Richard L. , Paterson W. R. , Frank L. A.
Published: September 2004

Long‐term‐averaged three‐dimensional data‐based models were made of the −30 < x < −10, ∣y∣ < 15, ∣z∣ < 5 RE plasma sheet region. The average magnetic moments 〈μ〉 and Chew‐Goldberger‐Low (CGL) double adiabatic parameters α⊥ and α∥ were evaluated for ions and electrons. It was shown that restricting the observations to those taken within 0.2 RE of the Bx = 0 point gave both a good determination of conditions at the neutral sheet and enough data points for reliable averages. Large pitch angle anisotropies would develop if the CGL parameters were constant along drift paths. In contrast, pitch angle scattering was so rapid that the observed plasma remained almost isotropic and it was the CGL parameters that varied markedly along the drift paths. Frequent ion scattering is explained by the chaotic nature of ion orbits, but electrons usually spiral around magnetic field lines even at the neutral sheet. Electron scattering by an average of 90° was needed during the 1 min it takes for a typical flux tube to undergo a net earthward displacement of 0.1 RE. A fast flow flux tube could move several Earth radii during this characteristic scattering time period. Rapid electron scattering also provides a mechanism to divert perpendicular current to form Birkeland current, produces diffusion, and generates a heat flux. The long‐term‐averaged magnetization vector M was evaluated and used to calculate the magnetization or bound current density jm = ∇ × M. The magnetization current and an almost oppositely directed perpendicular free or guiding center drift current jf were strongest near the neutral sheet. Their sum, the total perpendicular current density j⊥, was an order of magnitude smaller than either jm or jf in this region.
Nonlinear dynamics of the firehose instability in a magnetic dipole geotail
Authors: Horton W. , Xu B.‐Y. , Wong H. V. , Van Dam J. W.
Published: September 2004

The nonlinear dynamics of the firehose instability provides a possible explanation for the onset of the magnetic fluctuations associated with bursty bulk flows and substorms. Magnetic fluctuations called Pi2 geomagnetic pulsations are associated with bursty flows in the geotail plasma, where the plasma pressure exceeds the magnetic pressure. These strong magnetic fluctuations are often associated with substorms and start a few minutes before the arrival of the dipolarization pulse. Motivated by these observations, we have derived a nonlinear partial differential equation and developed an initial value code to investigate the firehose anisotropy‐driven turbulence in the Earth's geotail. We show that Hall MHD and dispersive ion kinetic effects limit the range of unstable parallel wavenumbers and determine the frequency spectrum of the turbulence. Nonlinear saturation is caused by the nonlinear weakening at large magnetic field line distortions of the destabilizing magnetic curvature force driven by the pressure anisotropy.
Putative shorelines in northern Arabia Terra, Mars
Authors: Webb Valerie E.
Published: September 2004

Three putative shorelines first proposed byParker et al.[1989] are topographically and morphologically evaluated within a 700,000 km2study area in northern Arabia Terra, Mars. Results are consistent with a shoreline interpretation for the Arabia and Deuteronilus contacts but do not support the proposed Acidalia shoreline. The Arabia contact follows an equipotential surface with a mean elevation of −3707 m and a mean deviation of ±13 m. For Deuteronilus, results suggest that the originally proposed shoreline represents two distinct, regional shorelines, because two separate portions of the original Deuteronilus contact approximate equipotential surfaces of −4200 m ± 5 m and −4000 m ± 6 m. For both the Deuteronilus and Arabia contacts, there is geomorphic evidence for erosion, and some landforms are similar to analogous terrestrial coastal landforms. These results permit, but do not prove, the past existence of an ocean ponded within the northern lowlands, possibly as recently as the Amazonian.
Observation of enhanced water vapor in Asian dust layer and its effect on atmospheric radiative heating rates
Authors: Kim Sang‐Woo , Yoon Soon‐Chang , Jefferson Anne , Won Jae‐Gwang , Dutton Ellsworth G. , Ogren John A. , Anderson Theodore L.
Published: September 2004

This study investigates the effect of water vapor associated with mineral dust aerosols on atmospheric radiative heating rates using ground‐based lidar, aircraft, radiosonde measurements and a radiation model during Asian dust events in the spring of 2001. We found enhanced levels of water vapor within the dust layer relative to the air above and below the dust layer. The water vapor led to an increase in the net radiative heating rate within the dust layer, changing the heating rate vertical structure. A net cooling was calculated above the dust layer as a result of low aerosol and drier conditions. Our finding suggests that the presence of water vapor within dust layer acts to enhance the temperature of this layer, potentially influencing the static stability of the dust layer. This finding is supported by an increase in the potential temperature at the top and bottom of the dust layer.
Electro‐osmotic coupling in compact clays
Authors: Rosanne M. , Paszkuta M. , Thovert J.‐F. , Adler P. M.
Published: September 2004

Electro‐osmotic coefficients are determined experimentally and compared to numerical data. The numerical model assumes random packings of grains of various shapes; the prediction corresponds to a modified analytical solution. A special set up was designed to measure all relevant properties independently as functions of the porosity and electrolyte concentration. Two model clays and a compact natural clay were used. Good agreement was found between experimental and numerical results, indicating that the electro‐osmotic coefficient can be predicted from conductivity and permeability.
Anomalous topography in the western Atlantic caused by edge‐driven convection
Authors: Shahnas M. Hosein , Pysklywec Russell N.
Published: September 2004

The western Atlantic region contains a long‐wavelength intraplate topography anomaly that is defined by the NE‐SW trending Bermuda Rise and two adjacent topography lows. Using numerical experiments, we test the hypothesis that the anomalous topography may be the surface response to edge‐driven convection. A primary edge‐driven convection cell and secondary flow circulation develops at a modeled continent‐ocean plate margin and induces subsidence at the continent‐ocean margin, an off‐shore peak/plateau of high topography on the ocean plate, and distal ocean plate subsidence. Unlike hot spots, the edge‐driven convection cell and associated topography migrate with moving surface plates. The flow cell and wavelength of topography is broadened with continent‐ward motion of the lithosphere relative to the mantle, whereas a migration in the ocean‐ward direction suppresses the formation of the edge‐driven convection cell and surface topography. The wavelength of observed anomalous topography in the western Atlantic and estimates of plate motions relative to a fixed hot spot reference frame are consistent with the former.
Multiscale electrodynamics of the ionosphere‐magnetosphere system
Authors: Streltsov A. V. , Lotko W.
Published: September 2004

In this paper we investigate how the parameters of the ionosphere and the low‐altitude magnetosphere mediate the formation and spatiotemporal properties of small‐scale, intense electromagnetic structures commonly observed by low‐altitude satellites in the auroral and subauroral magnetosphere. The study is based on numerical modeling of a time‐evolving, nonlinear system that describes multiscale electrodynamics of the magnetosphere‐ionosphere coupled system in terms of field‐aligned currents, both quasi‐static and Alfvénic. Simulations show that intense electric fields and currents with a perpendicular size of 10–20 km at 120 km altitude can be generated by a large‐scale, slowly evolving current system interacting with a weakly conducting ionosphere, even without a resonant cavity in the magnetosphere. These structures form in the strong gradient in the ionospheric conductivity that develops at the boundary between the large‐scale upward and downward currents when the background ionospheric Pedersen conductivity, ΣP, is low but higher than the Alfvén conductivity, ΣA = 1/μ0vA, above the ionosphere. When ΣP ≈ ΣA the ionosphere can generate electromagnetic waves with perpendicular sizes less than 10 km. These waves can be trapped inside the cavity of the classical ionospheric Alfvén resonator, and their amplitude can be significantly amplified there by the ionospheric feedback instability.