bluuebunny/crossref_metadata_2025 huggingface dataset:
Population profiles of a stable, commensalistic bacterial culture grown with toluene under sulphate‐reducing conditions
Authors: Vogt Carsten , Lösche Andreas , Kleinsteuber Sabine , Müller Susann
Published: July 2005

Background

Most bacteria present in nature are not culturable in pure culture by means of classic cultivation methods (Pace NR, 1997, Science 276:734–740; Amann RI et al., 1995, Microbiol Rev 59:143–169.). However, it was recently shown that most aerobic heterotrophic bacteria could grow only on artificial media when other micro‐organisms are present (Kaeberlein T et al., 2002, Science 296:1127–1129). Because the sulphate reducer Desulfobacula toluolica DSM 7467 and a bacterium (strain MV1) identified as Cellulosimicrobium sp. were not culturable unaccompanied, flow cytometry was used to highlight the strains' relation within the consortium.

Methods

DNA patterns were used to provide strain‐specific information about population proliferation dynamics. Cells were grown anaerobically and fed with toluene under sulphate‐reducing conditions.

Results

Oxidation of toluene occurred only in association with sulphate reduction and growth of D. toluolica. A characteristic chromosomal pattern, with at least six subpopulations of D. toluolica, appeared during the stationary phase, and asymmetric cell division was detected. The accompanying strain MV1 grew repeatedly to a high percentage of the culture only in certain growth phases of D. toluolica independently of the feeding substrate toluene.

Conclusions

A commensalistic relation between the two strains is suggested. The repeated rapid and frequent changes of the quantities within the community subsets are indicative of very flexible adaptations to changing environmental conditions, reflecting the need for modulated cell states and the ability to use every available source of carbon and energy for survival. © 2005 Wiley‐Liss, Inc.
Abelson, enabled, and p120catenin exert distinct effects on dendritic morphogenesis in Drosophila
Authors: Li Wenjun , Li Yan , Gao Fen‐Biao
Published: July 2005

Neurons exhibit diverse dendritic branching patterns that are important for their function. However, the signaling pathways that control the formation of different dendritic structures remain largely unknown. To address this issue in vivo, we use the peripheral nervous system (PNS) of Drosophila as a model system. Through both loss‐of‐function and gain‐of‐function analyses in vivo, we show here that the nonreceptor tyrosine kinase Abelson (Abl), an important regulator of cytoskeleton dynamics, inhibits dendritic branching of dendritic arborization (DA) sensory neurons in Drosophila. Enabled (Ena), a substrate for Abl, promotes the formation of both dendritic branches and actin‐rich spine‐like protrusions of DA neurons, an effect opposite to that of Abl. In contrast, p120catenin (p120ctn) primarily enhances the development of spine‐like protrusions. These results suggest that Ena is a key regulator of dendritic branching and that different regulators of the actin cytoskeleton exert distinct effects on dendritic morphogenesis. Developmental Dynamics 234:512–522, 2005. © 2005 Wiley‐Liss, Inc.
Screening for cervical cancer in India: How much will it cost? A trial based analysis of the cost per case detected
Authors: Legood Rosa , Gray Alastair M. , Mahé Cedric , Wolstenholme Jane , Jayant Kasturi , Nene Bhagwan M. , Shastri Surendra S. , Malvi Sylla G. , Muwonge Richard , Budukh Atul M. , Sankaranarayanan Rengaswamy
Published: July 2005

The cost and cost effectiveness of screening previously unscreened women by VIA, cytology or HPV testing was investigated within a large cluster randomised trial involving 131,178 women in rural India. All resources involved in implementation, training, management, recruitment, screening and diagnosis were identified and costed. We estimated the total costs and detection rates for each cluster and used these data to calculate an average cluster cost and detection rate for each screening approach. These estimates were combined to estimate a cost per case of cervical intraepithelial neoplasia grade 2/3 or invasive cancer (CIN 2/3+) detected. The average total costs per 1,000 women eligible for screening were US$3,917, US$6,609 and US$11,779 with VIA, cytology and HPV respectively. The cost of detecting a case of CIN2/3+ using VIA was $522 (95% CI $429–$652). Our results suggest that more CIN2/3+ cases would be detected in the same population if cytology were used instead of VIA and each additional case would cost US$1065 (95% CI $713–$2175). Delivering cervical cancer screening is potentially expensive in a low‐income country although costs might be lower outside a trial setting. We found screening with VIA to be the least expensive option, but it also detected fewer cases of CIN2/3+ than other methods; its long‐term cost‐effectiveness will depend on the long‐term benefits of early detection. Cytology was more effective at detecting cases than VIA but was also more expensive. Our findings indicate that HPV may not be a cost effective screening strategy in India at current consumable prices. © 2005 Wiley‐Liss, Inc.
Gene expression profiling in the mammary gland of rats treated with 7,12‐dimethylbenz[a]anthracene
Authors: Papaconstantinou Andriana D. , Shanmugam Ilanchezhian , Shan Liang , Schroeder Insa S. , Qiu Cunping , Yu Minshu , Snyderwine Elizabeth G.
Published: July 2005

Identification of molecular markers of early‐stage breast cancer development is important for the diagnosis and prevention of the disease. In the present study, we used microarray analysis to examine the differential expression of genes in the rat mammary gland soon after treatment with a known chemical carcinogen, 7,12‐dimethylbenz[a]anthracene (DMBA), and prior to tumor development. Six weeks after DMBA, differential expression of multiple genes involved in cell growth, differentiation and microtubule dynamics were observed. Gene expression changes were further validated by a combination of techniques, including real‐time PCR, RT‐PCR, Western blotting and immunohistochemistry. An inhibition of differentiation in this early stage was suggested by the lower expression of β‐casein and transferrin and higher expression of hsp27 in glands from DMBA‐treated rats. Possible cell cycle deregulation was indicated by an increased expression of cyclin D1 and hsp86, a heat shock protein associated with cyclin D1. Prior to tumor development, DMBA increased cellular proliferation as detected by Ki‐67 and stathmin immunostaining in histologically normal mammary gland. Genes regulating microtubule function, including stathmin, Ran, α‐tubulin and hsp27, were all overexpressed in the mammary gland of DMBA‐treated rats, raising the possibility that disruption of microtubule dynamics and abnormal mitosis may be critical events preceding breast cancer development. Several of the altered proteins, including hsp27, hsp86 and stathmin, may ultimately serve as markers of early breast cancer development. Published 2005 Wiley‐Liss, Inc.
FXYD3 is overexpressed in pancreatic ductal adenocarcinoma and influences pancreatic cancer cell growth
Authors: Kayed Hany , Kleeff Jörg , Kolb Armin , Ketterer Knut , Keleg Shereen , Felix Klaus , Giese Thomas , Penzel Roland , Zentgraf Hanswalter , Büchler Markus W. , Korc Murray , Friess Helmut
Published: July 2005

The expression and localization of FXYD domain containing ion transport regulator 3 (FXYD3), a transmembrane protein that acts as a chloride channel or chloride channel regulator, was analyzed in pancreatic tissues derived from donors and patients suffering from chronic pancreatitis (CP) or pancreatic ductal adenocarcinoma (PDAC) as well as in pancreatic cancer cells using QRT‐PCR, laser‐capture microdissection and microarray analysis, in situ hybridization and immunohistochemistry. FXYD3 antisense expressing T3M4 pancreatic cancer cells were generated and compared to control cells using anchorage‐dependent and independent growth assays, and xenotransplantation into nude mice. FXYD3 mRNA levels were 3.4‐fold increased in PDAC tissues compared to donor specimens (p = 0.006), and 3.9‐fold increased in microdissected cancer cells compared to normal pancreatic ductal cells (p = 0.02). FXYD3 was localized in the tubular complexes and PanIN lesions of both CP and PDAC, as well as in pancreatic cancer cells. Downregulation of FXYD3 by stable antisense transfection increased significantly the doubling time of T3M4 pancreatic cancer cells from 44 ± 2 hr to 55 ± 12 hr (p = 0.02). Nude mice transplanted with antisense transfected cells displayed a significant increase in tumor doubling time from 3.3 days ± 1.0 to 4.3 days ± 0.43 (p = 0.058). Anchorage‐independent growth and sensitivity to 5‐fluorouracil, gemcitabine and cisplatin as well as to MgCl2 were not dependent on the level of FXYD3 expression. In conclusion, overexpression of FXYD3 in pancreatic cancer may contribute to the proliferative activity of this malignancy. © 2005 Wiley‐Liss, Inc.
Transactivation of MCP‐1/CCL2 by β‐catenin/TCF‐4 in human breast cancer cells
Authors: Mestdagt Melanie , Polette Myriam , Buttice Giovanna , Noël Agnes , Ueda Atsuhisa , Foidart Jean‐Michel , Gilles Christine
Published: July 2005

The loss of E‐cadherin expression and the translocation of β‐catenin to the nucleus are frequently associated with the metastatic conversion of epithelial cells. In the nucleus, β‐catenin binds to the TCF/LEF‐1 (T‐cell factor/ lymphoid enhancer factor) transcription factor family resulting in the activation of several genes, some of them having important implications in tumour progression. In our study, we investigated the potential regulation of monocyte chemotactic protein‐1 (MCP‐1/CCL2) expression by the β‐catenin/TCF pathway. This CC‐chemokine has been implicated in tumour progression events such as angiogenesis or tumour associated macrophage (TAM) infiltration. We thus demonstrated that MCP‐1 expression correlates with the reorganization of the E‐cadherin/β‐catenin complexes. Indeed, MCP‐1 was expressed by invasive breast cancer cells (MDA‐MB‐231, BT549 and Hs578T), which do not express E‐cadherin but was not produced by noninvasive breast cancer cell lines (MCF7 and T47D) expressing high level of E‐cadherin. In addition, the MCP‐1 promoter was activated in BT549 breast cancer cells transfected with β‐catenin and TCF‐4 cDNAs. The MCP‐1 mRNA level was similarly upregulated. Moreover, we showed that MCP‐1 mRNA was downregulated after transfection with a siRNA against β‐catenin in both BT549 and Hs578T cells. Our results therefore identify MCP‐1 as a target of the β‐catenin/TCF/LEF pathway in breast tumour cells, a regulation which could play a key role in breast tumour progression. © 2005 Wiley‐Liss, Inc.
Hedgehog signaling is activated in subsets of esophageal cancers
Authors: Ma Xiaoli , Sheng Tao , Zhang Yuanxin , Zhang Xiaoli , He Jing , Huang Shuhong , Chen Kai , Sultz Josh , Adegboyega Patrick A. , Zhang Hongwei , Xie Jingwu
Published: July 2005

The hedgehog pathway plays a critical role in the development of the foregut. However, the role of the hedgehog pathway in primary esophageal cancers is not well studied. Here, we report that elevated expression of hedgehog target genes occurs in 14 of 22 primary esophageal cancers. The hedgehog signaling activation is not associated with tumor subtypes, stages, or differentiation. While the sonic hedgehog (Shh) transcript is localized to the tumor tissue, expression of Gli1 and PTCH1 is observed both in the tumor and in the stroma. We discovered that 4 esophageal squamous cell carcinomas, which overexpress Shh, have genomic amplification of the Shh gene. Treatment of esophageal cancer cells with smoothened antagonist, KAAD‐cyclopamine, or the neutralizing antibodies of Shh reduces cell growth and induces apoptosis. Overexpression of Gli1 under the CMV promoter renders these cells resistant to the treatments. Thus, our results indicate that elevated expression of Shh and its target genes is quite common in esophageal cancers. Our data also indicate that downregulation of Gli1 expression may be an important mechanism by which KAAD‐cyclopamine inhibits growth and induces apoptosis in esophageal cancer cells (supplementary material for this article can be found on the International Journal of Cancer website at http://www.interscience.wiley.com/jpages/0020‐7136/suppmat/index.html). © 2005 Wiley‐Liss, Inc.
Encapsulation and Controlled Release of a Hydrophobic Drug Using a Novel Nanoparticle‐Forming Hyperbranched Polyester
Authors: Zou Jianhua , Shi Wenfang , Wang Jun , Bo Jun
Published: July 2005

Summary: An amphiphilic, hyperbranched polymer suitable for use in controlled drug delivery is reported. This polymer was obtained by modification of the hyperbranched aliphatic polyester Boltorn™ H20 (H20) with succinic anhydride and then glycidyl methacrylate, and formed nanoparticles in aqueous solution. The critical association concentration was 7.4 × 10−3 g · L−1, as determined by fluorescence spectroscopy using pyrene as a molecular probe. A static/dynamic laser light scattering (LLS) study revealed that the average particle size was 39.4 nm with a low particle size distribution (PDI = 0.04), and that each particle was composed of about 350 amphiphilic molecules. Daidzein, a hydrophobic traditional Chinese medicine, was encapsulated during particle formation and the release properties were determined. The optimal feeding concentration of daidzein to hyperbranched polyester was 4.9 × 10−5 g · mL−1 to 5.0 × 10−3 g · mL−1 with a loading efficiency of 76.1%. In the presence of the enzyme Lipase PS, the drug loaded nanoparticles degraded in a random one‐by‐one manner and released the drug over a few days. This system is therefore a novel controlled drug release system based on nanoparticles formed of hyperbranched polyester.

Encapsulation of daidzein by hyperbranched polyester particles.

magnified image

Encapsulation of daidzein by hyperbranched polyester particles.
Ishikawa iterative process with errors for nonlinear equations of generalized monotone type in Banach spaces
Authors: Ćirić Ljubomir B. , Ume Jeong Sheok
Published: July 2005

The concept of the operators of generalized monotone type is introduced and iterative approximation methods for a fixed point of such operators by the Ishikawa and Mann iteration schemes {xn} and {yn} with errors is studied. Let X be a real Banach space and T : D ⊂ X → 2D be a multi‐valued operator of generalized monotone type with fixed points. A new general lemma on the convergence of real sequences is proved and used to show that {xn} converges strongly to a unique fixed point of T in D. This result is applied to the iterative approximation method for solutions of nonlinear equations with generalized strongly accretive operators. Our results generalize many of know results. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Weighted inequalities for iterated maximal functions in Orlicz spaces
Authors: Kita Hiro‐o
Published: July 2005

Let M be the classical Hardy‐Littlewood maximal operator. The object of our investigation in this paper is the iterated maximal function Mkf(x) = M(Mk−1f) (x) (k ≥ 2). Let Φ be a φ‐function which is not necessarily convex and Ψ be a Young function. Suppose that w is an A′∞ weight and that k is a positive integer. If there exist positive constants C1 and C2 such that

equation image

then there exist positive constants C3 and C4 such that

equation image

where the functions a(t) and b(t) are the right derivatives of Φ(t) and Ψ(t), respectively. Conversely, if w is an A1 weight, then (II) implies (I). Another necessary and sufficient condition will be given. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An extension of an inequality of I. Schur
Authors: Nikolov Geno
Published: July 2005

Denote by πnthe set of all algebraic polynomials of degree at most n with complex coefficients. An inequality of I. Schur asserts that the first derivative of the transformed Tchebycheff polynomial$\overline {T}_n (x) = T_n (x \, \rm {cos} \, {{\pi} \over {2n}})$has the greatest uniform norm in [−1, 1] among allf∈ 𝒮n, where

equation image

Here we show that this extremal property of$\overline {T}_n$persists in the wider class of polynomialsf∈ πnwhich vanish at ±1, and for which there existn− 1 points$\{t_j\}^{n-1}_{j=1}$separating the zeros of$\overline {T}_n$and such that$|f(t_j)| \le |\overline {T}_n (t_j)|$forj= 1, …,n− 1. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Following Polymer Brush Growth Using the Quartz Crystal Microbalance Technique
Authors: Moya Sergio E. , Brown Andrew A. , Azzaroni Omar , Huck Wilhelm T. S.
Published: July 2005

Summary: The growth of surface‐initiated poly([2‐(methacryloyloxy)ethyl]trimethylammonium chloride) (pMETAC) brushes by ATRP was monitored by the quartz crystal microbalance technique with dissipation (QCM‐D). The change in mass of the quartz crystals starting from the adsorption of a thiol initiator monolayer through to the growth of the polymer brushes was determined. The use of QCM‐D allowed determination of the kinetics of polymerization from the surface. The technique can be applied to other polymers synthesised from surfaces and allows the study of varying conditions on the polymerization kinetics.

Changes in frequency of a quartz crystal during polymerization.

magnified image

Changes in frequency of a quartz crystal during polymerization.
Microstructurally Controlled Polyisoprene or Polystyrene Diblock Copolymers of rac‐Lactide
Authors: Amgoune Abderramane , Thomas Christophe M. , Balnois Eric , Grohens Yves , Lutz Pierre J. , Carpentier Jean‐François
Published: July 2005

Summary: A series of new polyisoprene‐block‐polylactide and polystyrene‐block‐polylactide diblock copolymers was prepared by combining the living anionic polymerization of isoprene or styrene, and the stereoselective ring‐opening polymerization of rac‐lactide. Aluminum and yttrium‐based polystyrene or polyisoprene macroinitiators yielded isotactic‐stereoblock and heterotactic‐enriched polylactide segments, respectively. A strong influence of the microstructure of the polylactide block on the aggregation properties in solution and morphological behavior of the solid materials in thin films has been observed.

General strategy used for the preparation of the diblock copolymers, illustrated here for poly(isoprene‐block‐lactide). Poly(styrene‐block‐lactide) copolymers were prepared similarly.

magnified image

General strategy used for the preparation of the diblock copolymers, illustrated here for poly(isoprene‐block‐lactide). Poly(styrene‐block‐lactide) copolymers were prepared similarly.
Thermotropic main‐chain liquid‐crystalline photodimerizable poly(vanillylidenealkyloxy alkylphosphate ester)s containing a cyclopentanone moiety
Authors: Sakthivel P , Kannan P
Published: July 2005

A new class of main‐chain liquid‐crystalline photodimerizable vanillylidene‐containing alkylpolyphosphate esters were synthesized from 2,5‐bis[m‐hydroxyalkyloxy(vanillylidene)] cyclopentanones with various alkylphosphoro‐ dichloridates by solution polycondensation in chloroform at ambient temperature. Their chemical structures were confirmed by FT‐IR, 1H, 13C and 31P NMR spectroscopic analysis. Dilute‐solution viscosity values were measured in order to obtain the intrinsic viscosities of the synthesized polymers. Mesogenic properties and phase behavior were investigated by the use of hot‐stage optical polarized microscopy and differential scanning calorimetry. Thermogravimetric analysis revealed that all of the polymers were stable up to 170–230 °C and decomposed with high char yields. The shorter methylene‐chain‐containing polymers did not show a liquid‐crystalline phase, while the longer methylene‐chain‐ containing polymers showed grainy and nematic textures. The Tg, Tm and Ti values of the polymers decreased with increasing flexible methylene chain length in the polymer backbones. The photocrosslinking properties of the polymers were studied by UV light/UV spectroscopy; the crosslinking proceeds via 2π–2π cycloaddition reactions of the vanillylidene exocyclic double bonds of the polymers. The rate of crosslinking was faster for the pendant ethoxy‐containing polymers than that of the pendant methoxy‐containing polymers. Copyright © 2005 Society of Chemical Industry
Study of the cross‐linking mechanism of a copolymer containing an electrooptic chromophore
Authors: Monnereau Cyrille , Blart Errol , Illien Bertrand , Paris Michaël , Odobel Fabrice
Published: July 2005

The mechanism of the cross‐linking reaction occuring between an NLO chromophore copolymerized with a glycidyl epoxide unit (polymer PIII) was rationalized using magic angle spinning (MAS) NMR spectroscopy. A first study conducted on a system composed of a model chromophore and a simple epoxy molecule enabled us to attribute the NMR changes that accompany the epoxy ring opening. Further, the use of a guest–host system made of an azo chromophore dispersed in an MMA–GMA copolymer matrix indicated a quantitative yield of the carboxyl/epoxy anchorage reaction after 30 min of heating at 140°C. The 13C cross polarization (CP)/MAS NMR spectroscopic study showed unambiguously that the cross‐linking reaction in polymer PIII is due to a nucleophilic opening of the epoxy rings by the carboxylic groups of the chromophores resulting in carboxylic ester bond formation. Finally, the blue shift of the ca 500 nm absorption band was modeled with a computational study. It is concluded that the esterification of the acid carboxylic group of the chromophore causes the torsion of the azo molecule. Copyright © 2005 John Wiley & Sons, Ltd.
About crosslinking of low molecular weight ethylene‐propylene(‐diene) copolymer‐based artificial latices
Authors: Tillier Delphine L. , Meuldijk Jan , Magusin Pieter C. M. M. , van Herk Alex M. , Koning Cor E.
Published: July 2005

Crosslinking of artificial latices based on ethylene–propylene copolymers (EPM) and/or ethylene–propylene–diene copolymers (EPDM) has not thoroughly been studied yet. Moreover, crosslinking of EPM and/or EPDM particles is a prerequisite for the formation of a shell using seeded emulsion polymerization of, for example, methyl methacrylate (MMA), as described elsewhere. Therefore, the aim of this article is to improve the general understanding of the chemistry involved in the crosslinking process. This work especially emphasizes the influence of the initiation method, that is, a peroxide or a pulsed electron‐beam, on crosslinking efficiency. All crosslinking efficiencies were obtained after extraction of the soluble polymer by tetrahydrofuran. The incorporation of the coagent, that is, divinylbenzene, into the EPM/EPDM phase was studied on a microscopic level by solid‐state 13C and 1H nuclear magnetic resonance (NMR). Crosslinking of a low molecular weight EPM/EPDM latex requires the presence of a coagent, for example, divinylbenzene, 1,6‐hexanediol diacrylate, or poly(1,2‐butadiene). The efficiency of crosslinking initiated by a pulsed electron‐beam was improved to a great extent by the presence, in the aqueous phase, of potassium nitrosodisulfonate, also referred to as Fremy salt. Matrix Assisted Laser Desorption/Ionization–Time of Flight–Mass Spectrometry (MALDI‐TOF‐MS) was used to determine the influence of electron‐beam irradiation on the chemical stability of surfactants. It was demonstrated that sodium dodecyl benzene sulfonate (SDBS) is not degraded by the irradiation, and is therefore the surfactant of choice for the stabilization of EPM/EPDM‐based latices subjected to electron‐beam irradiation. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3600–3615, 2005
LNG codes and process safety
Authors: Zinn C. Dale
Published: July 2005

Because of the potential wide area impact of an unplanned liquefied natural gas (LNG) release, the National Fire Protection Association (NFPA), and later the U.S. Department of Transportation, issued standards and regulations that included specific methodologies for analyzing the consequences of an accidental LNG release.

The concept of a “design spill” was defined to evaluate the consequences of an accidental LNG release, with particular attention to the influence of safety protective measures. In addition to specifying the magnitude of the unplanned release, the design spill also specified some of the parameters for estimation of the downwind LNG vapor dispersion and the extent of the radiant heat from an LNG pool fire. The “design spill” was an important concept because the LNG rules were the first (and still unique) to define “exclusion zones” for purposes of establishing the allowable sites for establishing LNG facilities.

This paper identifies the hazards associated with LNG use, discusses the development and use of the “design spill” concept, and identifies problems with this approach. A detailed historical review of the regulations, codes, and standards applicable to LNG facilities is also provided. Changes and modifications in these codes in the past few years have caused considerable confusion. Thus, a complete review and revision of the “design spill” concept is required. © 2005 American Institute of Chemical Engineers Process Saf Prog, 2005
Transient impairment of the adaptive response to fasting in FXR‐deficient mice
Authors: Cariou Bertrand , van Harmelen Kirsten , Duran-Sandoval Daniel , van Dijk Theo , Grefhorst Aldo , Bouchaert Emmanuel , Fruchart Jean-Charles , Gonzalez Frank J. , Kuipers Folkert , Staels Bart
Published: July 2005

The farnesoid X receptor (FXR) has been suggested to play a role in gluconeogenesis. To determine whether FXR modulates the response to fasting in vivo, FXR‐deficient (FXR−/−) and wild‐type mice were submitted to fasting for 48 h. Our results demonstrate that FXR modulates the kinetics of alterations of glucose homeostasis during fasting, with FXR−/− mice displaying an early, accelerated hypoglycaemia response. Basal hepatic glucose production rate was lower in FXR−/− mice, together with a decrease in hepatic glycogen content. Moreover, hepatic PEPCK gene expression was transiently lower in FXR−/−mice after 6 h of fasting and was decreased in FXR−/−hepatocytes. FXR therefore plays an unexpected role in the control of fuel availability upon fasting.
Regulation of lipopolysaccharide‐induced inflammatory response by glutathione S‐transferase P1 in RAW264.7 cells
Authors: Xue Bin , Wu Yifan , Yin Zhimin , Zhang Hong , Sun Suwen , Yi Tangsheng , Luo Lan
Published: July 2005

Glutathione S‐transferase P1(GSTP1) plays an important role in the detoxification and xenobiotics metabolism. Here, we show that GSTP1 is also involved in LPS (lipopolysaccharide)‐induced inflammatory response. GSTP1 expression, determined at the transcription and translation levels, were upregulated by the LPS stimulation in RAW264.7 macrophage‐like cells. GSTP1 inhibited LPS‐induced mitogen‐activated protein kinases MAPKs including ERK, JNK and p38 as well as NF‐κB activation dose‐ and time‐dependently in transient transfected and stable transfected cells. Moreover this inhibition of the signaling pathways resulted in the decrease of tumor necrosis factor alpha (TNF‐α) and nitric oxide (NO) synthesis. These data suggest that the GSTP1 prevents LPS‐induced excessive production of pro‐inflammatory factors and plays an anti‐inflammatory role in response to LPS.
Back on the balance sheet: The tax effects of contingent claims in commercial banking
Authors: Reagle Derrick
Published: July 2005

Contingent claims separate revenue and cost into two different time periods. Revenue comes in the initial origination process, while the cost comes upon completion of the contract in the event of default. With banks increasing contingent claims in recent years, a higher taxable income leads to a shift in a bank's balance sheet toward tax‐free income and tax‐shielding liabilities. This provides a valuable case‐study of corporate finance theories of tax management. This paper builds a model to illustrate the income features of contingent claims. Call Reports from 1990–1996 are examined, and show significant evidence of increases in leverage associated with contingent claims.
ROYAL INCAPACITY AND CONSTITUTIONAL CONTINUITY: THE REGENT AND COUNSELLORS OF STATE
Authors: Brazier Rodney
Published: July 2005

THE British monarch has legal duties to perform, as well as ceremonial and representative functions to discharge. For example, the monarch’s assent is legally required before a Bill or an Order in Council can pass into law; some appointments only take effect when they are formally approved by the monarch, which is sometimes signified by the Queen’s personal signature, the royal sign manual, or at others by personal delivery by the monarch of seals of office. Some types of document require as a matter of law the affixing of the Great Seal, which can usually be done only by virtue of a warrant under the royal sign manual: examples include royal proclamations (say to dissolve Parliament), or Letters Patent (say to confer a peerage or to ratify a treaty). Because the monarch is part of the legal machinery of government it is essential that the monarch is always available to function as such; but because a monarch is only human there will be times when, because of absence or illness, this is impossible.
Kissing the Old Class Politics Goodbye
Authors: Cobble Dorothy Sue
Published: July 2005

Verity Burgmann's call for a reinvigorated class politics and language is timely. This essay shares her goal of strengthening social movements in which class is taken seriously. It argues, however, that her efforts to resuscitate an antiquated class politics dressed up in identity clothes will not further that goal. This response offers an alternative reading of the nature and history of the “new” and the “old” social movements, of what can be learned about class and class-conscious movements from “identity politics” and from cultural theorists, and of what is needed to encourage future movements for social and economic justice. It calls for a class politics that recognizes the diversity of the working classes, embraces multiple class identities, reflects the fluid and multitiered class structures in which we live, and honors the aspirations of working people for inclusion, equity, and justice.
Modeling the effects of tidal loading on mid‐ocean ridge hydrothermal systems
Authors: Crone Timothy J. , Wilcock William S. D.
Published: July 2005

Tidal signals are observed in numerous time‐series measurements obtained from mid‐ocean ridge hydrothermal systems. In some instances these tidal signals are clearly the result of ocean currents, but in other instances it appears that the signals may originate in the subseafloor formation. In order to explore the effect of ocean tidal loading on mid‐ocean ridge hydrothermal systems, we apply a one‐dimensional analytical model of tidal loading on a poroelastic half‐space and develop a two‐dimensional numerical model of tidal loading on a poroelastic convection cell. The one‐dimensional models show that for a reasonable range of fluid, elastic, and hydrological properties, the loading efficiency may vary from near zero to near unity and the diffusive penetration depth for tidal pressure signals may vary from tens of meters to kilometers. The two‐dimensional models demonstrate that tides may generate significant vertical and horizontal pressure gradients in mid‐ocean ridge hydrothermal systems as a result of spatial variations in fluid temperatures and the elastic and hydrological properties of the crust. These continuum models predict that outflow temperature perturbations will be very small (<10−4°C), but in real systems where the continuum hypothesis does not always apply, the perturbations may be on the order of ∼0.1°C. The models predict relatively large perturbations to fluid velocity at the seafloor. For high‐temperature vents the outflow perturbations normalized to the mean flow velocity increase as the permeability decreases. Flow reversals at the seafloor are predicted in some regions of net low‐temperature outflow and net inflow during the tidal cycle. In the subseafloor, tidally induced flow perturbations are likely to significantly enhance mixing and fluid exchange below the seafloor in regions of slow flow and in regions where there are strong gradients in temperature or in the mechanical and hydrological properties of the crust. Tidally enhanced mixing and fluid exchange may significantly influence the extent and character of microbial production in the subseafloor.
Toward a taxon‐specific parameterization of bio‐optical models of primary production: A case study in the North Atlantic
Authors: Claustre Hervé , Babin Marcel , Merien Davy , Ras Joséphine , Prieur Louis , Dallot Serge , Prasil Ondrej , Dousova Helena , Moutin Thierry
Published: July 2005

As part of the Programme Océan Multidisciplinaire Méso Echelle (POMME) in the North Atlantic, an extensive data set of high‐pressure liquid chromatography pigment concentrations, phytoplankton absorption coefficients, primary production measurements, and P versus E curves has been acquired. This data set is analyzed with the objective of testing whether photosynthetic performances of natural phytoplankton communities are related to taxonomic characteristics. This objective is addressed in two ways. The first approach concerns the bulk photosynthetic performances of the water column: the water column photosynthetic cross section, ψ*, equals 0.088 m2 gChla−1, i.e., ∼25% higher than the average for the world ocean. Using multiple regression, size‐specific values of ψ* are subsequently derived: carbon storage by water column is more efficient with microphytoplankton (ψ* = 0.135 m2 gChla−1) than with nanophytoplankton (0.089 m2 gChla−1) or picophytoplankton (0.064 m2 gChla−1). The second (independent) approach examines the correlations between photophysiological properties and several abiotic and biotic variables. The correlations are weak, if any, between photophysiological properties and abiotic factors (temperature, nitrate concentration, and irradiance), while significant correlations are reported with biotic factors (proportion of the different phytoplankton groups, average size of the phytoplankton assemblage). Our results suggest that when large phytoplankton populations predominate at the expense of smaller ones, the specific absorption coefficient is expectedly lower, while other photophysiological properties αB, PmaxB, and Φcmax, are higher. The agreement between both independent approaches points out that large phytoplankton (essentially diatoms) are potentially more efficient in carbon storage than any other phytoplankton groups on a chlorophyll a or light absorption basis.
An alternative kinematic interpretation of Thetis Boundary Shear Zone, Venus: Evidence for strike‐slip ductile duplexes
Authors: Kumar P. Senthil
Published: July 2005

On Venus a 1000‐km‐long, 50‐ to 200‐km‐wide, anastomosing shear zone system (Thetis Boundary Shear Zone (TBSZ)) separates the eastern Ovda and northwestern Thetis Regiones. Previous workers mapped a part of this shear zone and interpreted it as a sinistral strike‐slip shear zone containing an extensional jog. In the present study it is reexamined for a detailed structural and kinematic analysis, and an alternative kinematic interpretation is provided. The TBSZ is divided into western, central, and eastern segments. The western segment is narrow and is oriented in a ENE‐WSW direction. Along its northern boundary the preexisting folds of tessera are cut by the shear zone, and the folds are dragged into parallelism with the shear zone in response to dextral strike‐slip motion. Both the western and central segments contain a pair of conjugate deformation bands (sigmoidal folds and linear ridges), which appear similar to S–C‐like structures of large‐scale ductile shear zones. The acute angle between the S and C bands suggests dextral sense of displacement. The eastern segment forms the northeastern restraining bend of the TBSZ, where the shear zone is characterized by a wide, branching, fan‐like anastomosing shear zone system with well‐developed contractional strike‐slip ductile duplexes. The internal fabric defined by the sigmoidal folds consistently shows dextral sense of displacement. Therefore the TBSZ is a dextral strike‐slip shear zone showing S–C‐like structures and contractional strike‐slip duplexes, similar to the continental‐scale ductile shear zones on Earth.
Crust‐mantle coupling in the Gulf of Cadiz (SW‐Iberia)
Authors: Stich Daniel , Mancilla Flor de Lis , Morales Jose
Published: July 2005

In the Gulf of Cadiz and Cape St. Vincent region at the SW‐Iberian margin, seismic catalogues report seismicity down to ∼100 km depth. According to structural models for the region, this includes earthquakes that occur in the uppermost continental mantle. We invert regional waveforms to estimate moment tensors and centroid depths for moderate earthquakes, obtaining eight solutions (Mw 3.8 to 5.3) between 6 and 60 km depth. Moment tensor solutions and previous source estimates show predominately reverse and strike‐slip faulting style with ∼NNW‐SSE oriented P‐axes, close to plate convergence between Africa and Eurasia. We obtain similar stress tensor estimates from crustal and upper mantle earthquakes, both with sub‐horizontal, ∼NNW σ1‐axes. This indicates analogous deformation in both domains, and that earthquakes are unrelated to any subduction process.
Size effect on the crystal structure of barium titanate nanoparticles
Authors: Yashima Masatomo , Hoshina Takuya , Ishimura Daiju , Kobayashi Syuuhei , Nakamura Wataru , Tsurumi Takaaki , Wada Satoshi
Published: July 2005

A size effect on crystal structure has been investigated for barium titanate (BaTiO3) nanoparticles of 40-, 140-, and 430-nm sizes, by means of neutron and high-resolution synchrotron x-ray powder-diffraction and Raman-scattering techniques. These samples were prepared by a modified two-step thermal decomposition method from barium titanyl oxalate, resulting in very few lattice impurities. Rietveld analysis of the neutron-diffraction data for the 430-nm- and 140-nm-sized BaTiO3 particles was performed assuming a single phase of tetragonal (P4mm) structure. The axial ratio c∕a of tetragonal BaTiO3 decreases with a decrease in particle size from 430 to 140 nm. Barium titanate particles with a size of 40 nm consist of (1) tetragonal crystals (83 wt %) with a large cell volume and an axial ratio of unity c∕a=1.000(5) and of (2) a hexagonal phase (P63mmc, 17 wt %) with a large unit-cell volume. Rietveld and maximum-entropy method analyses suggest that there exist atomic displacements from the ideal site of a cubic structure and a spontaneous polarization of the tetragonal phase even in the 40-nm-sized BaTiO3 particles. The nuclear-density distribution of the 140-nm-sized particles with a high dielectric constant does not exhibit a large positional disorder, while the Ba atom of tetragonal BaTiO3 in the 40-nm-sized particles has a smaller atomic displacement parameter.
Morphology control and material mixing by high-temperature organic vapor-phase deposition and its application to thin-film solar cells
Authors: Yang Fan , Shtein Max , Forrest Stephen R.
Published: July 2005

Organic vapor-phase deposition is used to grow photovoltaic cells consisting of molecular compounds that require high-evaporation temperatures. The organic crystal size and film morphology are controlled by adjusting the source evaporation temperature, substrate temperature, carrier gas flow rate, and chamber pressure. The resulting surface morphology produces a highly folded donor–acceptor interface with a fourfold increase in area compared with a planar heterojunction, leading to an increased exciton diffusion efficiency, and hence an 80% increase in photovoltaic cell power conversion efficiency. Mixed organic layers with controlled constituent ratios and layer thicknesses are grown by the simultaneous codeposition of multiple source materials. Photovoltaic cells comprised of a copper phthalocyanine:C60 mixed layer show comparable performance to analogous vacuum-deposited cells.
Space charge saturated sheath regime and electron temperature saturation in Hall thrusters
Authors: Raitses Y. , Staack D. , Smirnov A. , Fisch N. J.
Published: July 2005

Existing electron-wall interaction models predict that secondary electron emission in Hall thrusters is significant and that the near-wall sheaths are space charge saturated. The experimental electron-wall collision frequency is computed using plasma parameters measured in a laboratory Hall thruster. In spite of qualitative similarities between the measured and predicted dependencies of the maximum electron temperature on the discharge voltage, the deduced electron-wall collision frequency for high discharge voltages is much lower than the theoretical value obtained for space charge saturated sheath regime, but larger than the wall recombination frequency. The observed electron temperature saturation appears to be directly associated with a decrease of the Joule heating rather than with the enhancement of the electron energy loss at the walls due to a strong secondary electron emission. Another interesting experimental result is related to the near-field plasma plume, where electron energy balance appears to be independent on the magnetic field.
Binding energies of hydrogen molecules to isoreticular metal-organic framework materials
Authors: Sagara Tatsuhiko , Klassen James , Ortony Julia , Ganz Eric
Published: July 2005

Recently, several novel isoreticular metal-organic framework (IRMOF) structures have been fabricated and tested for hydrogen storage applications. To improve our understanding of these materials, and to promote quantitative calculations and simulations, the binding energies of hydrogen molecules to the MOF have been studied. High-quality second-order Møller–Plesset (MP2) calculations using the resolution of the identity approximation and the quadruple zeta QZVPP basis set were used. These calculations use terminated molecular fragments from the MOF materials. For H2 on the zinc oxide corners, the MP2 binding energy using Zn4O(HCO2)6 molecule is 6.28kJ∕mol. For H2 on the linkers, the binding energy is calculated using lithium-terminated molecular fragments. The MP2 results with coupled-cluster singles and doubles and noniterative triples method corrections and charge-transfer corrections are 4.16kJ∕mol for IRMOF-1, 4.72kJ∕mol for IRMOF-3, 4.86kJ∕mol for IRMOF-6, 4.54kJ∕mol for IRMOF-8, 5.50 and 4.90kJ∕mol for IRMOF-12, 4.87 and 4.84kJ∕mol for IRMOF-14, 5.42kJ∕mol for IRMOF-18, and 4.97 and 4.66kJ∕mol for IRMOF-993. The larger linkers are all able to bind multiple hydrogen molecules per side. The linkers of IRMOF-12, IRMOF-993, and IRMOF-14 can bind two to three, three, and four hydrogen molecules per side, respectively. In general, the larger linkers have the largest binding energies, and, together with the enhanced surface area available for binding, will provide increased hydrogen storage. We also find that adding up NH2 or CH3 groups to each linker can provide up to a 33% increase in the binding energy.
Hollow to bamboolike internal structure transition observed in carbon nanotube films
Authors: Wang Y. Y. , Gupta S. , Nemanich R. J. , Liu Z. J. , Qin L. C.
Published: July 2005

The transition of the internal structure in microwave chemical-vapor-deposited carbon nanotubes is investigated using scanning electron microscopy and high-resolution transmission electron microscopy. By controlling the thickness of the iron catalyst layer, a sequence of carbon nanotube films was obtained with diameters ranging from a few nanometers to over 100nm. Experiments have established that by continuous reduction of the Fe layer thickness to <1nm, single- and double-wall carbon nanotube films can be produced, whereas for an Fe film thickness >1nm, multiwall carbon nanotube films can be synthesized. It was also found that for an Fe thickness ⩾5nm, interlayers (i.e., bamboolike or periodically compartmentalized nanotubes) were formed, while for an iron thickness <2nm the tubes were primarily hollow. For an intermediate Fe thickness the internal structure of the carbon nanotubes was a mixture of hollow and bamboolike. A growth model which considers bulk and surface diffusions of carbon into and∕or onto the Fe catalyst surface is proposed to describe this transition and the internal periodic structure.
Density functional theory study of indirect nuclear spin-spin coupling constants with spin-orbit corrections
Authors: Oprea Corneliu I. , Rinkevicius Zilvinas , Vahtras Olav , Ågren Hans , Ruud Kenneth
Published: July 2005

This work outlines the calculation of indirect nuclear spin-spin coupling constants with spin-orbit corrections using density functional response theory. The nonrelativistic indirect nuclear spin-spin couplings are evaluated using the linear response method, whereas the relativistic spin-orbit corrections are computed using quadratic response theory. The formalism is applied to the homologous systems H2X (X=O,S,Se,Te) and XH4 (X=C,Si,Ge,Sn,Pb) to calculate the indirect nuclear spin-spin coupling constants between the protons. The results confirm that spin-orbit corrections are important for compounds of the H2X series, for which the electronic structure allows for an efficient coupling between the nuclei mediated by the spin-orbit interaction, whereas in the case of the XH4 series the opposite situation is encountered and the spin-orbit corrections are negligible for all compounds of this series. In addition we analyze the performance of the density functional theory in the calculations of nonrelativistic indirect nuclear spin-spin coupling constants.
Anharmonic midinfrared vibrational spectra of benzoic acid monomer and dimer
Authors: Antony Jens , von Helden Gert , Meijer Gerard , Schmidt Burkhard
Published: July 2005

Anharmonic vibrational calculations for the benzoic acid monomer and dimer in the mid-IR regime (500–1800cm−1) are reported. Harmonic frequencies and intensities are obtained at the DFT/B3LYP level of theory employing D95(d,p) and cc-pVTZ basis sets. Anharmonic corrections obtained from standard perturbation theory lead to redshifts of 1%–3%. In almost all cases, the resulting frequencies deviate by less than 1% from previous measurements [Bakker et al., J. Chem. Phys. 119, 11180 (2003)]. Calculated intensities are in qualitative agreement with the absorption experiment, with the cc-pVTZ values being superior to the D95(d,p) ones for a few modes of the dimer. The antisymmetric out-of-plane bending mode of the dimer, which is strongly blueshifted with respect to the monomer frequency, represents a remarkable exception: The harmonic frequencies obtained for the two basis sets differ notably from each other, and the anharmonically corrected frequencies deviate from the experimental value by 8% [D95(d,p)] or 3% (cc-pVTZ). Nonperturbative calculations in reduced dimensionality reveal that the relatively small total anharmonic shift (few tens of cm−1) comprises of partly much larger contributions (few hundreds of cm−1) which are mostly canceling each other. Many of the individual anharmonic couplings are beyond the validity of second-order perturbation theory based on cubic and semidiagonal quartic force constants only. This emphasizes the need for high-dimensional, nonperturbative anharmonic calculations at high quantum-chemical level when accurate frequencies of H-atom vibrations in double hydrogen bonds are sought for.