bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterizations of the class Δta2 over Euclidean spaces
Authors: Hemmerling Armin
Published: August 2004

We present some characterizations of the members of Δta2, that class of the topological arithmetical hierarchy which is just large enough to include several fundamental types of sets of points in Euclidean spaces ℝk. The limit characterization serves as a basic tool in further investigations. The characterization by effective difference chains of effectively exhaustible sets yields only a hierarchy within a subfield of Δta2. Effective difference chains of transfinite (but constructive) order types, consisting of complements of effectively exhaustible sets, as well as another closely related concept, yield a rich hierarchy within the whole class Δta2. The presentation always first reports analogies between Hausdorff's difference hierarchy within the Borel class ΔB2 and Ershov's hierarchy within the class Δ02 of the arithmetical hierarchy; after that the counterparts for Δta2 are developed. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Type‐2 computability on spaces of integrable functions
Authors: Kunkle Daren
Published: August 2004

Using Type‐2 theory of effectivity, we define computability notions on the spaces of Lebesgue‐integrable functions on the real line that are based on two natural approaches to integrability from measure theory. We show that Fourier transform and convolution on these spaces are computable operators with respect to these representations. By means of the orthonormal basis of Hermite functions in L2, we show the existence of a linear complexity bound for the Fourier transform. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Baire category and nowhere differentiability for feasible real functions
Authors: Breutzmann Josef M. , Juedes David W. , Lutz Jack H.
Published: August 2004

A notion of resource‐bounded Baire category is developed for the classPC[0,1]of all polynomial‐time computable real‐valued functions on the unit interval. The meager subsets ofPC[0,1]are characterized in terms of resource‐bounded Banach‐Mazur games. This characterization is used to prove that, in the sense of Baire category, almost every function inPC[0,1]is nowhere differentiable. This is a complexity‐theoretic extension of the analogous classical result that Banach proved for the classC[0, 1] in 1931. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Computability and continuity in metric partial algebras equipped with computability structures
Authors: Dahlgren Fredrik
Published: August 2004

In this paper we give an axiomatisation of the concept of a computability structure with partial sequences on a many‐sorted metric partial algebra, thus extending the axiomatisation given by Pour‐El and Richards in [9] for Banach spaces. We show that every Banach‐Mazur computable partial function from an effectively separable computable metric partial Σ‐algebraAto a computable metric partial Σ‐algebraBmust be continuous, and conversely, that every effectively continuous partial function with semidecidable domain and which preserves the computability of a computably enumerable dense set must be computable. Finally, as an application of these results we give an alternative proof of the first main theorem for Banach spaces first proved by Pour‐El and Richards. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
First steps in constructive game theory
Authors: Bridges Douglas S.
Published: August 2004

The minimax theorem of matrix game theory is examined from a constructive point of view. It is then shown that the existence of solutions for matrix games cannot be proved constructively, but that a 2‐by‐2 game with at most one solution has a constructible solution. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fast quantum algorithms for handling probabilistic and interval uncertainty
Authors: Kreinovich Vladik , Longpré Luc
Published: August 2004

In many real‐life situations, we are interested in the value of a physical quantity y that is difficult or impossible to measure directly. To estimate y, we find some easier‐to‐measure quantities x1, … , xn which are related to y by a known relation y = f(x1, … , xn). Measurements are never 100% accurate; hence, the measured values $ \tilde {x} _{i} $ are different from xi, and the resulting estimate $ \tilde {y} = f( \tilde {x} _{1} \ldots , \tilde {x} _{n}) $ is different from the desired value y = f(x1, … , xn). How different can it be? Traditional engineering approach to error estimation in data processing assumes that we know the probabilities of different measurement errors $ \Delta x_i {\mathop {=} \limits ^{\rm def}} \tilde x _i - x_i $. In many practical situations, we only know the upper bound Δi for this error; hence, after the measurement, the only information that we have about xi is that it belongs to the interval $ {\bf x}_i {\mathop {=} \limits ^{\rm def}} [ \tilde x _i - \Delta _i, \tilde x_i + \Delta _i] $. In this case, it is important to find the range y of all possible values of y = f(x1, … , xn) when xi ∈ xi. We start the paper with a brief overview of the computational complexity of the corresponding interval computation problems: Most of the related problems turn out to be, in general, at least NP‐hard. In this paper, we show how the use of quantum computing can speed up some computations related to interval and probabilistic uncertainty. We end the paper with speculations on whether (and how) “hypothetic” physical devices can compute NP‐hard problems faster than in exponential time. Most of the paper's results were first presented at NAFIPS'2003 [30]. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Global non‐existence of solutions of a class of wave equations with non‐linear damping and source terms
Authors: Messaoudi Salim A. , Houari Belkacem Said
Published: August 2004

In this paper we consider the non‐linear wave equation

a,b>0, associated with initial and Dirichlet boundary conditions. We prove, under suitable conditions on α,β,m,p and for negative initial energy, a global non‐existence theorem. This improves a result by Yang (Math. Meth. Appl. Sci. 2002; 25:825–833), who requires that the initial energy be sufficiently negative and relates the global non‐existence of solutions to the size of Ω. Copyright © 2004 John Wiley & Sons, Ltd.
Use of recombinant factor VIIa (rFVIIa) to control intraoperative bleeding in pediatric brain tumor patients
Authors: Heisel M. , Nagib M. , Madsen L. , Alshiekh M. , Bendel A.
Published: August 2004

Surgical bleeding during the resection of brain tumors in children may be related to tumor vascularity, pathology, and location. Despite improvements in neurosurgical technique, neuroanesthesia, and blood product replacement, bleeding can be life‐threatening in these surgeries. We report eight pediatric patients in whom recombinant factor VIIa (rFVIIa) was used to control intraoperative bleeding during surgical resection of pediatric brain tumors. rFVIIa should be considered as a method to control intraoperative bleeding that is unresponsive to conventional interventions. Additional studies are needed to determine optimal patient selection and drug dosing, efficacy and safety. © 2004 Wiley‐Liss, Inc.
Attention and information processing in survivors of childhood acute lymphoblastic leukemia treated with chemotherapy only
Authors: Mennes Maarten , Stiers Peter , Vandenbussche Erik , Vercruysse Gertrui , Uyttebroeck Anne , Meyer Geert De , Van Gool Stefaan W.
Published: August 2004

Background

Omitting radiotherapy for central nervous system (CNS) prophylaxis has improved the overall quality of life for long‐term survivors of childhood acute lymphoblastic leukemia (ALL). However, recent reports suggest minor cognitive impairment in survivors who received chemotherapy only.

Procedure

This study focused on attentional functioning and speed of information processing in 23 children previously treated for ALL according to EORTC 58881 and EORTC 58951 protocol. Patients received intrathecal methotrexate combined with high doses intravenous methotrexate as CNS prophylaxis. Cognitive functioning was assessed with the Amsterdam Neuropsychological Tasks, a computerized attention assessment program. Variables of both speed and accuracy of the patients were compared with those obtained from 23 age‐ and sex‐matched control children.

Results

Patients were equal to control children concerning baseline speed, sustained attention, response inhibition, and response organization. However, they were significantly slower than controls in three tasks: encoding, memory search letters, and focused attention 4‐letters. Interactions with the difficulty of the task were found. There were no differences in number or type of errors between groups on all tasks.

Conclusions

ALL survivors treated with chemotherapy have specific information processing difficulties. They process information slower than control children, especially when more information has to be processed or when attention has to be focused precisely. In spite of being slower, patients are equally accurate compared to control children. © 2004 Wiley‐Liss, Inc.
Time trends of childhood cancer mortality rates: A report from the childhood cancer registry of piedmont, Italy, 1971–1998
Authors: Zuccolo Luisa , Pastore Guido , Maule Milena , Gregori Dario , Terracini Benedetto , Merletti Franco , Magnani Corrado
Published: August 2004

Time changes in mortality rates can be used to suggest future trends in the prognosis of childhood cancer. Estimates provided from recent studies led to divergent previsions of future trends. In this study we used data from the population‐based Childhood Cancer Registry of Piedmont (CCRP) in order to measure the decrease in mortality. The study included 1,060 deaths in the period 1971–1998. Analyses were carried out using Poisson regression models and considered separately the total tumours, acute lymphoblastic leukaemia (ALL) and tumours of the central nervous system (CNS). We observed a progressive decline in the mortality rates: for all tumours the estimated annual percentage change was −3.6% (P < 0.05), for ALL it was −5.2%, (P < 0.05) and for CNS tumours it was −3.8% (P < 0.05). The statistical test for effect modification due to age at death was not significant. For all cancer types, the Poisson model fits the data well, corresponding to an exponential decrease of mortality rates and leading to the conclusion that current therapies, despite their proven effectiveness, are not sufficient to cure all cases of childhood cancer. Pediatr Blood Cancer 2004;43:788–791. © 2004 Wiley‐Liss, Inc.
Physical and cognitive‐behavioral activities used in the home management of sickle pain: A daily diary study in children and adolescents
Authors: Dampier Carlton , Ely Elizabeth , Eggleston Barry , Brodecki Darcy , O'Neal Patricia
Published: August 2004

Background

There is little information documenting the use of cognitive‐behavioral and physical pain relieving activities by children and adolescents for management of pain related to sickle cell disease (SCD).

Methods

Thirty‐seven subjects (aged 6–21 years) used a daily self‐report pain diary for 6 months to 3 years to report their home pain experience and its pharmacologic and non‐pharmacologic management.

Results

A total of 514 vaso‐occlusive pain episodes (2,592 days) were reported. Cognitive‐behavioral or physical pain management activities were used alone on 7.5% of these pain days, and with analgesics on 77%. Female gender (P = 0.003) and increasing pain intensity (P = 0.04) were associated with an increased number of activities used. Increasing pain intensity was also associated with usage of several specific activities.

Conclusions

Patients and families frequently used cognitive‐behavioral and physical activities in addition to oral analgesics to treat sickle cell‐related pain at home, and may benefit from additional training and support. © 2004 Wiley‐Liss, Inc.
Two‐dimensional gel electrophoresis database of murine R1 embryonic stem cells
Authors: Elliott Steven T. , Crider David G. , Garham Christopher P. , Boheler Kenneth R. , Van Eyk Jennifer E.
Published: August 2004

Embryonic stem (ES) cell lines represent a population of undifferentiated pluripotent cells capable of multilineage differentiation in vitro. Although very useful for studying developmental processes, human ES cell lines have also been suggested as a potential and unlimited source for cellular transplantation and the treatment of human disease. The proteomic basis of embryonic stemness (pluripotentiality and multilineage differentiation) and the transitions that lead to specific cell lineages however, remain to be defined. As an important first step in defining these processes, we have performed a proteomic analysis of undifferentiated mouse R1 ES cell lines using pH 3–10, 4–7 and 6–11 two‐dimensional electrophoresis gels, matrix‐assisted laser desorption/ionization and tandem mass spectrometry. Of the 700 gel spots analyzed, 241 distinct protein species were identified corresponding to 218 unique proteins, with a significant proportion functionally related to protein expression.
Studies on peptide acetylation for stable‐isotope labeling after 1‐D PAGE separation in quantitative proteomics
Authors: Yu Yanling , Cui Jiefeng , Wang Xiaoyan , Liu Yinkun , Yang Pengyuan
Published: August 2004

Acetylation is a single labeling process to label peptides in control and experimental samples universally, and is independent of amino acid composition or post‐translational modification. Here, we propose a new strategy especially useful to quantify either hydrophobic or extremely acidic and basic proteins involved in acetylation of tryptic peptides after sodium dodecyl sulfate polyarcylamide gel electrophoresis (SDS‐PAGE) separation. We studied some essential parameters of acetylation labeling reactions in either in‐solution tryptic peptides or in‐gel digested extracts systematically. We have found that the acetylation efficiency varies markedly on account of different reactive systems, and demonstrated that stable isotope labeling can be steadily obtained with in‐gel digested peptides under optimized conditions. We use this protocol to quantify some proteins of two kinds of hepatocellular carcinoma cell line, non‐metastatic hepatocellular carcinoma cells, Hep3B, and metastatic hepatocellular carcinoma cells, MHCC97‐H. The experimental results provide positive evidence for the potential application of an acetylation labeling strategy in quantitative proteomics, and an efficient way for global proteome quantification.
Induction of Mycobacterium avium proteins upon infection of human macrophages
Authors: Brunori Lara , Giannoni Federico , Bini Luca , Liberatori Sabrina , Frota Cristiane , Jenner Peter , Thoresen Ove Fredrik , Orefici Graziella , Fattorini Lanfranco
Published: August 2004

Induction of Mycobacterium avium proteins labelled with [35S]methionine and mRNAs upon infection of the human macrophage cell line THP‐1 was investigated by two‐dimensional gel electrophoresis‐mass spectrometry and reverse transcriptase‐polymerase chain reaction (RT‐PCR), respectively. M. avium overexpressed proteins within the macrophages that are involved in fatty acids metabolism (FadE2, FixA), cell wall synthesis (KasA), and protein synthesis (EF‐tu). The correlation of differential protein and mRNA expression varied between good and no correlation. Overall, these four proteins may be involved in the adaptation and survival of M. avium within human macrophages.
Diverse proteomic alterations in gastric adenocarcinoma
Authors: He Qing‐Ye , Cheung Yim Hing , Leung Suet Yi , Yuen Siu Tsan , Chu Kent‐Man , Chiu Jen‐Fu
Published: August 2004

Gastric adenocarcinoma is one of the most common cancers in Asian countries including China. Although its incidence rates in the West are lower than that in Asia, gastric cancer is still a major health problem worldwide, being second only to lung cancers in the number of deaths it causes. Helicobacter pylori infection has been identified as the major pathogen, but the detailed pathogenesis of gastric carcinoma remains elusive. Due to the lack of suitable and specific biomarkers for early detection, most cases of the disease are diagnosed at late stages and the survival rate is low. In this study, we used a proteomic approach to globally analyze the protein profiles of paired surgical specimens of primary gastric adenocarcinoma and nontumor mucosa aiming at identifying specific disease‐associated proteins as potential clinical biomarkers and for carcinogenetic study. Compared to nontumor tissues, multiple protein alterations were found in tumor tissues. Some of these alterations involve variations in the expression of cytoskeleton proteins, including an increase in cytokeratin 8 and tropomyosin isoform and a decrease in cytokeratin 20. Co‐up‐regulations of heat‐shock proteins and glycolytic enzymes were observed in tumor tissues, indicating self‐protective efforts of cells and the growing energy requirement during malignant transformation. Diverse regulations also occurred with proteins involved in cell proliferation and differentiation, such as GMP reductase 2 and creatine kinase B, and proteins bearing potential tumor suppressor activities, including prohibitin and selenium binding protein 1. More interestingly, a human stomach‐specific protein, 18 kDa antrum mucosa protein, was found to be dramatically under‐expressed in cancer tissues, implicating a possible special pathological role for this protein in gastric carcinogenesis. Further comprehensive evaluation by globally considering the altered factors may result in the discovery of a biomarker index for effective assessment of the disease and may provide in‐depth information for better understanding the pathogenesis of gastric cancer.
The serum proteome of Equus caballus
Authors: Miller Ingrid , Friedlein Arno , Tsangaris George , Maris Antony , Fountoulakis Michael , Gemeiner Manfred
Published: August 2004

We constructed a reference two‐dimensional protein map for horse (Equus caballus) serum. The serum proteins were separated by two‐dimensional electrophoresis (2‐DE); 29 different gene products were identified. Proteins represented by 25 spots/spot groups were identified by tandem nanoelectrospray mass spectrometry (MS), four by matrix‐assisted laser desorption ionization time‐of‐flight (TOF) MS and one was sequenced by TOF‐TOF technology. The identities of four proteins were deduced by similarity to the human plasma protein database. In selected cases, i.e. the immunoglobulins, immunoblotting with specific antibodies provided additional information about the respective proteins. Albumin was detected as the full‐length protein and as fragments of various sizes. Spots representing products of different mass and charge were also detected for α1‐antitrypsin, haptoglobin and transthyretin. Thus, despite the fact that the Equus caballus genome is incompletely characterizated, we were able to identify almost all moderate to high abundance proteins stained in the serum 2‐DE pattern.
A novel proteomic coculture model of prostate cancer cell growth
Authors: Dvorzhinski Dmitri , Thalasila Anu , Thomas Paul E. , Nelson Deirdre , Li Hong , White Eileen , DiPaola Robert S.
Published: August 2004

Chemotherapy and androgen ablation therapy are only temporarily effective against prostate cancer, and current studies are ongoing to test agents that target proteins responsible for autocrine and paracrine stimulated growth. Given limitations of current laboratory models to test the effect of these agents on cell growth and protein targets, we developed a coculture model that can distinguish paracrine stimulated growth and effects on proteins. We found that LNCaP prostate cancer cells and an immortalized rat prostate cell line transfected to overexpress the antiapoptotic resistance protein Bcl‐2 were stimulated to grow (>2‐fold increase, p < 0.01) through autocrine effects from additional cells in an upper chamber of our system. Using a proteomic approach with a two‐dimensional differential in gel electrophoresis method to increase fidelity, four proteins were found to increase after autocrine induced growth stimulation. These proteins were all identified by mass spectrometry as enzymes in the glycolytic pathway, validating the ability of this system to detect both clonogenic growth and the effect on proteins. These data, therefore, demonstrate a novel coculture model for further study of agents that target proteins in pathways of paracrine or autocrine stimulated cell growth.
Assessment of protein spot components applying correspondence analysis for peptide mass fingerprint data
Authors: Krah Alexander , Wessel Ralf , Pleißner Klaus‐Peter
Published: August 2004

Proteins separated by two‐dimensional gel electrophoresis (2‐DE) may be distributed over several spots. Otherwise, one spot may contain more than one component. The same protein occurring in several spots supposedly represents differently modified protein species that might be of biological relevance. Identification of spots with peptide mass fingerprinting and database searching leads only to the detection of the major spot components. If a spot also contains additional minor protein components, quantitation of spots with protein staining techniques or antibody detection becomes misleading. In order to find spots containing minor components we applied correspondence analysis, a multivariate data exploration method, to peptide mass fingerprint data. Correspondence analysis using peak lists revealed groups of spots containing the same protein with their characteristic mass‐to‐charge ratio (m/z) values. In order to detect different protein spot components an interactive threshold setting and removal of m/z values with subsequent recalculation of the correspondence analysis using our software tool CorrAn are performed. The usefulness of this methodical approach was shown by a data set of peptide mass fingerprints of 284 spots of Helicobacter pylori 26695 separated by 2‐DE.
Low virulent strains of Candida albicans: Unravelling the antigens for a future vaccine
Authors: Fernández‐Arenas Elena , Molero Gloria , Nombela César , Diez‐Orejas Rosalía , Gil Concha
Published: August 2004

Several low virulent Candida albicans mutant strains: CM1613 (deleted in the Mitogen Activated Protein (MAP) Kinase MKC1), CNC13 (deleted in the MAP‐kinase HOG1) and the morphological mutant 92' were used as vaccines employing a murine model of systemic candidiasis. In this vaccination trial, only the CNC13 strain was able to induce protection against a subsequent infection with a lethal dose of the wild‐type strain. The protection induced by CNC13 vaccinated animals resulted in 60–70% percent of survival. These results demonstrate that collaboration between cellular and humoral responses, induced by the CNC13 mutant, elicited a long lasting and effective protection. Using a proteomic approach (two‐dimensional gel electrophoresis followed by Western blotting), twenty‐five C. albicans immunogenic proteins were detected and identified by matrix‐assisted laser desorption/ionization and/or tandem mass spectrometry. We were able to define an antibody pattern in the sera from the nonvaccinating strains (92' and CM1613), which was different from the profile detected in the sera from surviving animals (vaccinated with the CNC13 mutant). The utility of this proteomic approach has allowed us to identify antigens that induce protective IgG2a antibody isotype in the sera from vaccinated animals: enolase (Eno1p), pyruvate kinase (Cdc19p), pyruvate decarboxylase (Pdc11p), a component from the 40S ribosomal subunit (Bel1p), triosephosphate isomerase (Tpi1p), DL‐glycerol phosphatase (Rhr2p), fructose‐bisphosphate aldolase (Fba1p) and two new protective antigens: IMP dehydrogenase (Imh3p), and acetyl‐CoA synthetase (Acs2p). The antigenic proteins that promote protective antibodies described in this work are excellent candidates for a future fungal vaccine; their heterologous expression and vaccine design is currently underway.
Electrophoretic evidence for a new type of counterion condensation
Authors: Popov Alexei , Hoagland David A.
Published: August 2004

A systematic capillary electrophoresis study uncovered how polyelectrolyte effective charge density varies with backbone charge spacing and solvent dielectric constant. The study primarily focused on aliphatic ionenes, a special class of polyelectrolytes, which possess regularly spaced quaternary ammonium groups in the backbone. Complete ionization of functional units and good solvency in water or mixtures of water with lower dielectric constant solvents (methanol, acetonitrile) enabled continuous measurements of ionene effective charge density through the onset of counterion condensation. Ionenes with both uniform and alternating charge spacing were examined. As expected, effective charge density rose linearly with fixed charge density to a critical value, above which effective charge density remained constant. Deviating from expectation, the onset of condensation did not occur at a critical fixed charge density. Instead, condensation initiated at a constant critical Bjerrum length. The same onset condition was found for quaternized poly(vinyl pyridine)s. These experimental results suggest a new form of condensation, one driven by ion‐pairing of polyelectrolyte with counterions. In support of this hypothesis, the onset of condensation appeared to correlate with counterion size. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3616–3627, 2004
Amphiphilic maleic acid‐containing alternating copolymers—1. Dissociation behavior and compositions
Authors: Sauvage E. , Amos D. A. , Antalek B. , Schroeder K. M. , Tan J. S. , Plucktaveesak N. , Colby R. H.
Published: August 2004

The dissociation of the two adjacent carboxylic acids in maleic acid‐containing copolymers is expected to differ from those of poly(acrylic acid) and poly(methacrylic acid) where the acids are separated by two carbons on the backbone. In this work, we have employed potentiometric titration and NMR spectroscopy to characterize the dissociation behavior and chemical compositions of several water‐soluble maleic acid‐containing copolymers. A distinct two‐step process corresponding to the dissociation of the two adjacent carboxylic acids is observed in aqueous CaCl2 (0.02 N) solution for copolymers of maleic acid and isobutylene, diisobutylene, and styrene. Such a two‐step ionization process is less recognizable, however, for the copolymers of maleic acid and linear alkenes ranging from n‐hexene to n‐octadecene. Nevertheless, the compositions of all copolymers, including the extent of neutralization and the ratio of the comonomer moieties, are estimated from the titration curves. The chemical composition derived from potentiometry and NMR spectroscopy for all copolymers are approximately 1 : 1 (maleic acid : comonomer). With the exception of the hydrophobically modified copolymer of isobutylene‐maleic acid, no obvious conformational transition was observed over the whole range of ionization for these hydrophobic maleic acid‐containing copolymers. This is related to the aggregated state of these copolymers in aqueous media. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3571–3583, 2004
Synthesis and characterization of poly (styrene‐co‐vinyl phosphonate) ionomers
Authors: Wu Qi , Weiss R.A.
Published: August 2004

Poly(styrene‐co‐diethyl vinylphosphonate) copolymers were synthesized by free radical copolymerization. The ester groups of the copolymers were hydrolyzed to phosphonic acid groups, and the sodium and zinc salts ionomers were obtained by neutralization. The structure and the thermal and viscoelastic properties of the copolymers and ionomers were characterized by nuclear magnetic resonance, Fourier transform infrared spectroscopy, differential scanning calorimetry, dynamic mechanical analysis, and small‐angle X‐ray scattering. The phosphonate ester lowered the glass transition temperature (Tg) of polystyrene. The free acid derivatives and metal phosphonates increased Tg and produced a rubbery plateau region in the viscoelastic properties due to the formation of a physical network. The acid and salt ionomers exhibited microphase‐separated morphologies and were thermorheologically complex. The phosphonic acid derivatives absorbed relatively little water, even for materials with ion‐exchange capacities greater than 1.0 mEq/g, and were not conductive, which made them unsuitable for application as proton exchange membranes. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3628–3641, 2004
Evidence for occurrence of an organophosphate‐resistant type of acetylcholinesterase in strains of sea lice (Lepeophtheirus salmonis Krøyer)
Authors: Fallang Anders , Ramsay Jennifer Mara , Sevatdal Sigmund , Burka John F , Jewess Philip , Hammell K Larry , Horsberg Tor E
Published: August 2004

Acetylcholinesterase (AChE) is the target of a major pesticide family, the organophosphates, which were extensively used as control agents of sea lice on farmed salmonids in the early 1990s. From the mid‐1990s the organophosphates dichlorvos and azamethiphos were seriously compromised by the development of resistance. AChE insensitive to organophosphate chemotherapeutants has been identified as a major resistance mechanism in numerous arthropod species, and in this study, target‐site resistance was confirmed in the crustacean Lepeophtheirus salmonis Krøyer isolated from several fish‐farming areas in Norway and Canada. A bimolecular rate assay demonstrated the presence of two AChE enzymes with different sensitivities towards azamethiphos, one that was rapidly inactivated and one that was very slowly inactivated. To our knowledge this is the first report of target‐site resistance towards organophosphates in a third class of arthropods, the Crustacea. Copyright © 2004 Society of Chemical Industry
Identification of the Rdl mutation in laboratory and field strains of the cat flea, Ctenocephalides felis (Siphonaptera: Pulicidae)
Authors: Bass Chris , Schroeder Iris , Turberg Andreas , Field Linda M , Williamson Martin S
Published: August 2004

In many insect species, resistance to cyclodiene insecticides is caused by amino acid substitutions at a single residue (A302) within the M2 transmembrane region of the γ‐aminobutyric acid (GABA) receptor sub‐unit termed Rdl (resistance to dieldrin). These mutations (A302S and A302G) have also been shown to confer varying levels of cross‐resistance to fipronil, a phenylpyrazole insecticide with a similar mode of action to cyclodienes. To investigate the possible occurrence of these mutations in the cat flea, Ctenocephalides felis (Bouché), a 176‐bp fragment of the cat flea Rdl gene, encompassing the mutation site, was PCR amplified and sequenced from nine laboratory flea strains. The A302S mutation was found in eight of the nine strains analysed, although the relative frequency of the mutant allele varied between strains. Only one strain (R6) was found to be homozygous for the S302 allele in all the individuals tested, and this correlated with previous reports of low‐level fipronil resistance in this strain. A PCR‐based diagnostic assay, capable of screening individual fleas for this mutation, was developed and used to survey a range of fleas collected at random from veterinary clinics in the UK and USA. The A302S mutation was present at a high frequency in these domestic pet populations. Copyright © 2004 Society of Chemical Industry
Dissipation of three organochlorine and four pyrethroid pesticides sprayed in a greenhouse environment during hydroponic cultivation of gerbera
Authors: Hatzilazarou Stefanos P , Charizopoulos Emmanouel T , Papadopoulou‐Mourkidou Euphemia , Economou Athanasios S
Published: August 2004

A wide range of pesticides (insecticides, acaricides and fungicides) is used in the hydroponic cultivation of gerbera. The fate and behaviour of some of these commonly used pesticides (organochlorine and pyrethroid insecticides/acaricides) in a greenhouse installation was investigated. The concentrations of endosulfan, dicofol, tetradifon, permethrin, bifenthrin, cypermethrin and deltamethrin in the air of the greenhouse were related to their physicochemical properties and respective application rates. Of these compounds, endosulfan exhibited the highest concentration in the greenhouse air 2 h after application (10 µg m−3), due to its highest volatility; afterwards, up to 12 h post‐application, a rapid decrease was recorded which finally led to a concentration of 0.41 µg m−3 at 6 days post‐application. Dicofol exhibited the same trend of dissipation in the greenhouse air; its concentration decreased from 0.27 µg m−3 immediately after the application to 0.12 µg m−3 at 6 days post‐application. Tetradifon, bifenthrin and permethrin were found at concentrations lower than 0.1 µg m−3 at 2 h post‐application, and cypermethrin and deltamethrin could not be detected. The concentrations of all the above pesticides in the drain water of the open hydroponic system were relatively high immediately after application and decreased rapidly during the following 3 days. In the closed hydroponic system, all the pesticides accumulated in the nutrient solution during the first 24 h after application and slowly decreased in concentration over the following 3 days. The spray operators applying these pesticides were exposed to rather high concentrations and the spray deposits were monitored on the chest and forehead of the operator. Endosulfan exhibited the highest concentrations of the seven pesticides. The organochlorine pesticides (endosulfan, dicofol and tetradifon) were usually detected at higher concentrations on the chest than on the forehead of the operator; pyrethroids were detected at higher concentrations on the forehead than on the chest of the operator. Copyright © 2004 Society of Chemical Industry
Synthesis of chiral α‐amino aldehydes linked by their amine function to solid support
Authors: Cantel Sonia , Heitz Annie , Martinez Jean , Fehrentz Jean‐Alain
Published: August 2004

The anchoring of an α‐amino‐acid derivative by its amine function on to a solid support allows some chemical reactions starting from the carboxylic acid function. This paper describes the preparation of α‐amino aldehydes linked to the support by their amine function. This was performed by reduction with LiAlH4 of the corresponding Weinreb amide linked to the resin. The aldehydes obtained were then involved in Wittig or reductive amination reactions. In addition, the linked Weinreb amide was reacted with methylmagnesium bromide to yield the corresponding ketone. After cleavage from the support, the compounds were obtained in good to excellent yields and characterized. Copyright © 2004 European Peptide Society and John Wiley & Sons, Ltd.
A cyanobacterial gene encoding an ortholog of Pirin is induced under stress conditions
Authors: Hihara Yukako , Muramatsu Masayuki , Nakamura Kinu , Sonoike Kintake
Published: August 2004

Pirin is a recently identified protein in eukaryotes as a transcription cofactor or as an apoptosis‐related protein. Although Pirin is highly conserved from bacteria to human, there have been no reports on prokaryotic Pirin orthologs. We show here that pirA (sll1773) encoding an ortholog of Pirin together with an adjacent gene, pirB (ssl3389), was upregulated under high salinity and some other stress conditions in a cyanobacterium Synechocystis sp. PCC 6803. Induction of the pirAB genes was not related to cell death and disruption of pirA did not affect the gene expression profile. Expression of the pirAB genes was negatively regulated by a LysR family transcriptional regulator encoded by pirR (slr1871) located immediately upstream of pirAB in the divergent direction. DNA microarray analysis indicated that PirR repressed expression of closely located ORFs, slr1870 and mutS (sll1772), in addition to pirAB and pirR itself.
Plasmin cleaves the juxtamembrane domain and releases truncated species of the urokinase receptor (CD87) from human bronchial epithelial cells
Authors: Beaufort Nathalie , Leduc Dominique , Rousselle Jean-Claude , Namane Abdelkader , Chignard Michel , Pidard Dominique
Published: August 2004

The three‐domain (D1D2D3) urokinase receptor (CD87) is highly susceptible to cleavage within the D1–D2 linker sequence, but also within the juxtamembrane region by yet poorly characterized proteinases, allowing the release of D1 and D2D3 species in various (patho)physiological body fluids. Using immunoblot analysis and ELISA applied to a recombinant soluble CD87 and to CD87‐expressing epithelial cells, we establish that exogenous or in situ generated plasmin proteolyzes CD87 in the D1–D2 linker and D3 carboxyterminal sequences, producing a major soluble D2D3 species. Mass spectrometry analysis of the fragmentation of CD87‐related synthetic peptides, and aminoterminal sequencing of D2D3 reveal Arg83, Arg89, and Arg281 as residues targeted by plasmin within human CD87.
The nominal duration of TIPS bonds
Authors: Laatsch Francis E. , Klein Daniel P.
Published: August 2004

This paper studies the price responsiveness (effective duration) of U.S. government issued inflation‐indexed bonds, known by the acronym TIPS (Treasury Inflation‐Protected Securities), to changes in nominal interest rates, real interest rates, and expected inflation. Using the TIPS pricing formula derived by Laatsch and Klein [Q. Rev. Econ. Finance43 (2002) 405], we first confirm that TIPS bonds have zero sensitivity to changes solely in expected inflation. By changes solely in expected inflation, we mean that the real rate remains unchanged and the nominal rate changes in accordance with the established Fisher [Publ. Am. Econ. Assoc.11 (1896)] effect. We show that the first derivative of the TIPS price is zero whenever the real rate is held constant. Thus, the first partial derivative of the TIPS bond pricing formula with respect to expected inflation is zero and the first partial derivative of the TIPS bond price with respect to nominal rates is also zero, given, in each case, that we hold the real rate constant. We then temporarily shift the analysis to zero‐coupon TIPS bonds and zero‐coupon ordinary Treasury bonds. We prove that the nominal duration of zero‐coupon TIPS bonds equals that of zero‐coupon ordinary Treasury bonds when the real rate changes but expected inflation is held constant.

However, if expected inflation changes and the change in the nominal rate does not yield a constant real rate, zero‐coupon TIPS prices will change and they will change by a smaller percentage than will zero‐coupon ordinary Treasury bonds. We analyze TIPS responsiveness to changes in nominal rates under such conditions. We derive an approximation to effective duration that demonstrates that the effective durations of various maturity zero‐coupon TIPS bonds are approximately linear functions in time to maturity of the effective duration of the one‐year zero‐coupon TIPS bond, ceteris paribus.

Nominal effective duration of TIPS bonds is certainly of interest to fixed income portfolio managers that might have a desire to include such bonds in their portfolio. After all, the greater portion of a typical fixed income portfolio is in traditional, noninflation protected bonds whose major risk exposure is to changes in nominal rates. To properly assess the role of TIPS bonds in the portfolio, portfolio managers need information as to how TIPS bonds respond to the changes in nominal rates that are driving the price behavior of the bulk of the portfolio's assets. Prior to concluding the paper, we demonstrate how portfolio managers can calculate the nominal durations of coupon TIPS bonds using the zero‐coupon duration formula we derive.
Verhaltensbeobachtungen in dyadischen Interaktionssituationen
Authors: Spinath Birgit , Spinath Frank M.
Published: August 2004

Zusammenfassung: Vorgestellt wird ein Instrument zur Verhaltensbeobachtung in dyadischen Interaktionssituationen, die deutsche Form des Riverside Behavioral Q-Sort (RBQ; Funder, Furr & Colvin, 2000 ). Es zeigte sich, dass die Items des RBQ-D ( Spinath, Spinath & Funder, 2000 ) insgesamt akzeptable Reliabilitäten aufwiesen und geeignet waren, interindividuelle Differenzen im Verhalten von N = 88 Zielpersonen in einer Gesprächssituation abzubilden. Belege für die Validität des Verfahrens wurden im Rahmen eines multimethodalen Ansatzes gesammelt: Es ergaben sich erwartungsgemäße Zusammenhänge zwischen den Items des RBQ-D und Selbst-, Bekannten- und Fremdeinschätzungen der Dimensionen des Fünf-Faktoren-Modells der Persönlichkeit ( Costa & McCrae, 1992 ). Die Stärke der gefundenen Zusammenhänge entspricht dabei derjenigen aus anderen Studien zur Einschätzung von Persönlichkeitsmerkmalen bei minimaler Information. Mit Hilfe einer zusätzlichen Stichprobe (N = 46) konnten darüber hinaus erwartungskonforme Zusammenhänge zwischen RBQ-D-Maßen von eineiigen Zwillingen nachgewiesen werden. Insgesamt erscheint uns der RBQ-D ein brauchbares Instrument zur Erhebung sozialer Verhaltensweisen, das durch weitere Forschungsbemühungen noch weiter zu optimieren ist.
Handlungsfähigkeit und das Selbst
Authors: Biebrich Robert , Kuhl Julius
Published: August 2004

Zusammenfassung: Diese Studie befasst sich mit dem Problem der Bewältigung des Zustandes “Innerer Kapitulation”, der bei einer Überforderung durch komplexe Problemsituationen entstehen kann (s. Biebrich & Kuhl, 2003 ). Es wird konzeptuell begründet, dass die Bewältigung “Innerer Kapitulation” von der Widerstandsfähigkeit des Selbstschutzsystems abhängt: Das Verhältnis zwischen Komponenten des Selbstschutzsystems - “Innerer Sicherheit” und “Handlungsfähigkeit” - ist dabei sehr wichtig. Mit Hilfe der konfirmatorischen Faktorenanalyse wurden Messmodelle für die Konstrukte “Innere Sicherheit” und “Handlungsfähigkeit” überprüft. Mittels der Erstellung von Strukturgleichungsmodellen (SEM) auf der Basis des Programms LISREL 8 wurde das Verhältnis zwischen den beiden theoretischen Konstrukten untersucht: Es wurde ein signifikanter Einfluss der “Inneren Sicherheit” auf die “Handlungsfähigkeit” festgestellt, der unter bestimmten Umständen verschwinden kann. Verschiedene Persönlichkeitsmerkmale werden als Prädiktoren für “Innere Sicherheit” und “Handlungsfähigkeit” mittels der SEM-Methode überprüft und in Bezug auf das Problem individueller Unterschiede bei der Bewältigung “Innerer Kapitulation” diskutiert.
Episodic methane release events from Last Glacial marginal sediments in the western North Pacific
Authors: Uchida Masao , Shibata Yasuyuki , Ohkushi Ken'ichi , Ahagon Naokazu , Hoshiba Mayumi
Published: August 2004

According to recent observations of anomalous bottom‐simulating reflections (BSR), the northwest Pacific marginal sediments around Japan main islands bear large abundances of methane hydrate [Satoh, 2002]. During the Last Glacial, direct and indirect evidence accumulated from geochemical data suggests that methane episodically released from hydrate trapped in the seafloor sediments [Dickens et al., 1995; Hinrichs et al., 2003; Kennett et al., 2000]. Here we show that marginal sediments from the western North Pacific contain a hopanoid 17α(H), 21β(H)‐hop‐22(29)‐ene (diploptene) derived from the activity of methanotrophic bacteria in water column and/or surface sediment during a warming period (Interstadial 3) in the Last Glacial. The carbon isotopic compositions of diploptene range between −41.0‰ and −27.9‰ (relative to PDB). In the horizon indicative of a contribution of methanotrophic bacteria, foraminiferal isotope signals were also found with highly depleted 13C compositions of planktonic foraminifera (∼−1.9‰, PDB) and benthic foraminifera (∼−0.8‰, PDB), suggesting indirect records of enhanced incorporation of 13C‐depleted CO2 formed by methanotrophic process that use 12C‐enriched methane as their main source of carbon. From combined isotopic data of molecular (diploptene) and foraminifera, the most prominent signal of methane release was detected in the sediments deposited around 25.4 cal. kyr BP (∼100 year time span), corresponding to the Interstadial 3. This is the first evidence of methane hydrate instability in the open western North Pacific during the Last Glacial. Considering the glacial‐interglacial hydrographic conditions in this region, the instability of methane hydrate may be modulated by intermediate water warming and/or the lowering of sea level. Our results suggest that the western North Pacific marginal regions may be a profound effect on rapid global warming climate changes during the Last Glacial.
Fields of nonlinear regression models for inversion of satellite data
Authors: Pelletier Bruno , Frouin Robert
Published: August 2004

A solution is provided to a common inverse problem in satellite remote sensing, the retrieval of a variable y from a vector x of explanatory variables influenced by a vector t of conditioning variables. The solution is in the general form of a field of nonlinear regression models, i.e., the relation between y and x is modeled as a map from some space to a subset of a function space. Elementary yet important mathematical results are presented for fields of shifted ridge functions, selected for their approximation properties. These fields are shown to span a dense set and to inherit the approximation properties of shifted ridge functions. A serious mathematical difficulty regarding the practical construction of continuous fields of shifted ridge functions is pointed out; it is circumvented while providing grounding to a large class of construction methodologies. Within this class, a construction scheme that builds upon multilinear interpolation is described. When applied to the retrieval of upper‐ocean chlorophyll‐a concentration from space, the solution shows potential for improved accuracy compared with existing algorithms.
Latitude‐dependent vertical mixing and the tropical thermocline in a global OGCM
Authors: Canuto V. M. , Howard A. , Cheng Y. , Miller R. L.
Published: August 2004

In most ocean general circulation models (OGCM), mixing in the pycnocline is treated with a constant background diffusivity. This creates the following problem. To obtain the observed sharp equatorial thermocline, OGCMs must adopt a pycnocline diffusivity ten times smaller than observed at mid‐latitudes. The conflict can only be resolved by switching to a spatially variable mixing. In this work we present the GISS mixing model supplemented by Gregg et al.'s [2003] finding that the rate of dissipation of internal gravity waves is latitude dependent. We use the new GISS model in a global OGCM and obtain an equatorial thermocline in both the Atlantic and Pacific oceans that is sharper than without the latitude dependence. The model results for the Pacific compare favorably with Kessler's [1990] data. The meridional overturning in the Atlantic and the global poleward heat transport are nearly unchanged from the values obtained without latitude dependence.
Variability in Arctic sea ice drift
Authors: Pfirman Stephanie , Haxby William F. , Colony Roger , Rigor Ignatius
Published: August 2004

Analysis of Arctic sea ice drift from 1979–1997 using a Lagrangian perspective shows the complexities of ice drift response to variations in atmospheric conditions. Changes in ice dynamics influence the redistribution of ice, and any transported material, from different source areas. Sources of ice exported to Fram Strait shifted in about 1986/87 from dominance of the Kara Sea and Severnaya Zemlya to the New Siberian Islands, East Siberian Sea, and Chukchi Sea. Average travel time of multiyear ice within the perennial pack of the central Arctic Basin, reached a maximum in 1987/88, and decreased by at least 1 year between 1984–1989 and 1990–1997. Consistent with the observations of other investigators, this decrease in ice travel time occurred following a major export or “surge” of old ice to Fram Strait from the Beaufort Gyre in 1988 through 1990, which decreased the fraction of thick, ridged ice within the central basin.