bluuebunny/crossref_metadata_2025 huggingface dataset:
1‐Methyl‐3‐pyridine‐2‐yl‐thiourea as inhibitor for acid corrosion of stainless steel
Authors: Hosseini S. M. A. , Salari M. , Ghasemi M.
Published: May 2009

The inhibiting effect of 1‐methyl‐3‐pyridine‐2‐yl‐thiourea (MPT) on the corrosion of stainless steel in 0.5 M H2SO4 solution was investigated using weight loss and potentiostatic polarization techniques. The percentage inhibition efficiencies and surface coverage degrees increased with increasing additive concentration. Potentiostatic polarization studies revealed that MPT is of the mixed‐type inhibitor in 0.5 M H2SO4 solution. The adsorption of this inhibitor is also found to obey the Langmuir adsorption isotherm. From the adsorption isotherm, value of the ΔGads for the adsorption process was calculated. From the corrosion rate obtained at 25–55 °C Ea, ΔHa and possible mechanism have been proposed. Scanning electron microscopy (SEM) was done from the surface of the exposed sample indicating uniform film on the surface.
Influence of the sulphate reducing bacteria on API‐X70 steel corrosion
Authors: Rodriguez‐Hernandez M. , Galvan‐Martinez R. , Orozco‐Cruz R. , Martinez E. A. , Torres‐Sanchez R.
Published: May 2009

The corrosion behaviour of API X70 immersed in a specific medium with a strain of thermophilic sulphate reducing bacteria (SRB) was analysed. Anaerobic corrosion test was carry out for 32 days at 50 °C. During the exposure time, pH, sulphate (SO) and hydrogen sulphide (H2S) concentration were measured. Corrosion potential, linear polarization resistance and potentiodynamic polarization curve were used in order to get the influence of the SRB in the corrosion phenomenon. Scanning electron microscopy was used to determine corrosion morphology. Results show that the SRB activity influenced the overall corrosion process. The anodic branches in the polarization curves show a passivity feature, whereas, the cathodic branches were not affected. A localized corrosion attack was found.
The effects of various formwork surfaces on the corrosion performance of reinforcing steel in concrete
Authors: Subaşı S. , Arslan M. , Durmuş G.
Published: May 2009

In this study, the effects of various formwork surfaces on the corrosion performance of reinforcing steel in concrete were examined. For this purpose, seven formwork surfaces from populus nigra, pinus silvestris, steel sheet, and four of plywoods were prepared. Three of the plywood formworks were covered with different geotextile liners and drainage channel and holes were drilled on their surfaces. One of the plywood formworks having no processes on its surface was for control. Reinforcing steels were first embedded in formworks and then the concrete was poured. The samples were exposed to corrosion in a way of settling them in 5% NaCl solution. We tested the corrosion potential and bonding strength of the samples. Later, the mass loss and tensile strength were measured on reinforcing bars that were pulled out from the concrete. The chloride content and pH values were also tested on concrete powders. The results indicated that drained‐lined formwork (F5 with TB50 + F613 geotextile liner) compared to steel sheet (F4 undrained and unlined) gave 16% lower corrosion and 68% higher bonding strength on reinforcing bars embedded samples, 73% lower mass loss and 4% higher tensile strength on reinforcing bars, and 70% lower chloride content and 4% higher pH on concrete powders. In addition, it was found that the corrosion strength of reinforcing steels in concrete could be increased if drained‐lined formworks were utilized.
Corrosion fatigue of a manganese–nitrogen stabilized austenitic stainless steel
Authors: Sonnleitner R. , Mori G. , Panzenböck M. , Fluch R.
Published: May 2009

Austenitic chromium–manganese–nitrogen stabilized stainless steels have been developed to replace chromium–nickel–nitrogen stainless steels in certain applications. In comparison, chromium–manganese–nitrogen steels have improved mechanical properties and acceptable corrosion resistance in hot, high chloride containing media. In this paper, corrosion fatigue investigations of a solution annealed and for practice more relevant 14% cold worked high alloyed chromium–manganese–nitrogen steel have been done. Inert glycerine was used as reference media and 62% calcium chloride solution as corrosive media, both aerated at a temperature of 120 °C. The stress ratio between upper and lower stress levels was 0.05 (tension–tension loading) to avoid the destruction of the fracture surfaces. As testing frequency for the dynamic experiments, 20 Hz was chosen considering possible application areas. Maximum stress versus number of cycles curves were recorded and representative specimens were investigated in a scanning electron microscope. In addition, electrochemical tests, exposure tests and constant load tests were done. This paper shows results on the corrosion fatigue of a manganese–nitrogen stabilized austenitic steel in a hot high chloride containing salt solution and helps to get a better understanding of occurring failure mechanisms.
Morphology Development of Polymer Blends in Extruder: The Effects of Compatibilization and Rotation Rate
Authors: Li Huaping , Sundararaj Uttandaraman
Published: May 2009

The effects of reactive compatibilization and extruder rotation rate on morphology development of polymer blends are studied. Morphology develops faster in compatibilized blends than that in their uncompatibilized counterparts. Based on force analysis, it has been proved that compatibilization facilitates dispersion by reducing slip at the interface of polymer phases. Rotation rate influences the morphology development of polymer blends by changing the residence time of polymers in the extruder. For uncompatibilized blends, the 400 rpm run results in finer microstructure at the outlet of the extruder than the 1 000 rpm run. Compatibilization suppresses this effect by reaching a steady‐state morphology before the outlet and results in similar microstructure for the 400 and 1 000 rpm runs.

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Fluorescent Superparamagnetic Polylactide Nanoparticles by Combination of Miniemulsion and Emulsion/Solvent Evaporation Techniques
Authors: Urban Markus , Musyanovych Anna , Landfester Katharina
Published: May 2009

Biodegradable and fluorescent polylactide nanospheres loaded with iron oxide particles of different sizes (either 10 or 25 nm) were prepared by the combination of miniemulsion and emulsion/solvent evaporation techniques. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) studies indicate that the obtained particles have uniform and spherical shape with an average size between 80–120 nm. The size of the particles mainly depends on the molecular weight of the used polylactide. The iron oxide content and the encapsulation homogeneity were determined from the thermogravimetric analysis and preparative ultracentrifugation, respectively. The obtained particles displayed superparamagnetic properties. Additional incorporation of the hydrophobic fluorescent dye gives the possibility to employ the obtained composite particles as model markers in order to study, for example, cellular uptake mechanism.

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Morphology and Photophysical Properties of DB‐PPV/PMMA Luminescent Electrospun Fibers
Authors: Chen Hsieh‐Chih , Liu Cheng‐Liang , Bai Chi‐Chung , Wang Nian‐Hau , Tuan Chih‐Shan , Chen Wen‐Chang
Published: May 2009

Morphology and photophysical properties of DB‐PPV/PMMA blend luminescence ES fibers were tuned though various solvents and DB‐PPV content. The blend fiber prepared from solvents with different boiling points led to various aggregated morphology of DB‐PPV, such as core‐shell or wire‐like structures. The absorption and luminescence peak maxima were red‐shifted with the larger DB‐PPV aggregation size or increasing blend content, but the luminescence quantum efficiency showed a decreasing trend. Moreover, highly‐aligned DB‐PPV/PMMA blend ES fibers with polarized emission were successfully prepared using a modified collector design. The present study suggests that the morphology and photophysical properties could be efficiently tuned through solvent type and conjugated moiety content.

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Indestructibility and stationary reflection
Authors: Apter Arthur W.
Published: May 2009

If κ < λ are such that κ is a strong cardinal whose strongness is indestructible under κ ‐strategically closed forcing and λ is weakly compact, then we show that

A = {δ < κ | δ is a non‐weakly compact Mahlo cardinal which reflects stationary sets}

must be unbounded in κ. This phenomenon, however, need not occur in a universe with relatively few large cardinals. In particular, we show how to construct a model where no cardinal is supercompact up to a Mahlo cardinal in which the least supercompact cardinal κ is also the least strongly compact cardinal, κ 's strongness is indestructible under κ ‐strategically closed forcing, κ 's supercompactness is indestructible under κ ‐directed closed forcing not adding any new subsets of κ, and δ is Mahlo and reflects stationary sets iff δ is weakly compact. In this model, no strong cardinal δ < κ is indestructible under δ ‐strategically closed forcing. It therefore follows that it is relatively consistent for the least strong cardinal κ whose strongness is indestructible under κ ‐strategically closed forcing to be the same as the least supercompact cardinal, which also has its supercompactness indestructible under κ ‐directed closed forcing not adding any new subsets of κ (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cracking risk of partially saturated porous media—Part II: Application to drying shrinkage
Authors: Pichler Bernhard , Dormieux Luc
Published: May 2009

Drying of deformable porous media results in their shrinkage, and it may cause cracking provided that shrinkage deformations are hindered by kinematic constraints. Herein, we focus on slow drying of an initially water‐saturated sample of a microheterogeneous poroelastic material damaged by parallel mesocracks. The cracking risk is analyzed by means of the thermodynamics‐based microporoelasticity model described in the companion paper (Part I), which is extended toward consideration of the hierarchical organization of cracked argillite. Drying of a material sample is studied in a framework where macrodisplacements in direction of the crack normal are blocked, while elsewise macrostress‐free boundary conditions prevail. The model implies that the opening/closure behavior of the cracks is governed by an effective pressure, in which the average crack (under)pressure, making the crack opening smaller, competes with the average micropore (under)pressure that makes the crack opening larger. The driving force for crack propagation is a quadratic function of this effective pressure. The model proposes that if drying shrinkage deformations are hindered by kinematic constraints, onset of cracking becomes possible once air entry into the cracks is observed. Copyright © 2009 John Wiley & Sons, Ltd.
Environmentally benign preparation of bifunctional cation exchange fibers
Authors: Zhang Qikun , Zhang Sujuan , Yang Ying , Chen Shuixia
Published: May 2009

A bifunctional cation exchange fiber was prepared by an efficient and environmentally benign method. In this method, sodium p‐styrene sulfonate (SSS) was cografted directly onto the polypropylene (PP) fiber along with acrylic acid (AA), which eliminated the sulfonation process of grafting fiber with concentrated sulfuric acid or chlorosulfonic acid in the conventional method. Effects of the grafting conditions such as reaction temperature, reaction time, pH value, and the influence of acrylic acid and metallic salt on the graft copolymer reaction were investigated. The physicochemical properties of the cation exchange fibers were characterized with diffuse reflectance infrared spectroscopy (FT‐IR), scanning electron microscopy (SEM), X‐ray diffractometer (XRD), thermal gravimetric analysis (TGA), TG‐IR analysis, and monofilament tensile properties test. The experimental results indicate that the optimal conditions of pre‐irradiation grafting are 80°C for 5 hr, and the mechanical properties and thermal stability of the product are better than those of commercial materials (Fiban.K‐1). The total static ion exchange capacity (IEC) of the cationic exchange fiber is up to 5.33 mmol/g. The maximal IEC contribution from the strong acid part is 2.47 mmol/g. This synthetic method provides a clean industrial way for the preparation of bifunctional cation exchange fibers. Copyright © 2009 John Wiley & Sons, Ltd.
Adhesion control for injection overmolding of polypropylene with elastomeric ethylene copolymers
Authors: Dondero Marco , Pastor José M. , Carella José M. , Perez Claudio J.
Published: May 2009

Two types of random semicrystalline copolymers (ethylene–octene and ethylene–butene) were overmolded on a core polypropylene. Maximum solid–liquid interface temperature achieved for the overmolding injection process is used as the key parameter for adhesion control. The main bonding process is shown to be a Rouse‐type fingering mechanism that develops in short time scales. Normalized peel tests were conducted on overmolded samples to measure the resulting polypropylene copolymers' bonding strength. All the ethylene random copolymers used for this study give good adhesion to polypropylene in overmolding processes, provided the right range of interface temperature is reached. Adhesion strength can be easily controlled for efficient debonding and recycling of used overmolded parts. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Peroxide‐controlled degradation of polypropylene using a tetra‐functional initiator
Authors: Scorah Matthew J. , Zhu Shuihan , Psarreas Alexander , McManus Neil T. , Dhib Ramdhane , Tzoganakis Costas , Penlidis Alexander
Published: May 2009

The purpose of this work is to evaluate a new tetra‐functional peroxide initiator and offer comparisons with a di‐functional peroxide commonly used in the production of controlled‐rheology polypropylene (CRPP) resins. CRPP resins have been produced by reactive processing in a batch mixer by using various equivalent amounts of a tetra‐functional and a conventional di‐functional peroxide at two different temperatures. At a lower processing temperature (200°C), the chain length of CRPP decreases with increasing initiator concentration of the di‐functional initiator, while in the case of tetra‐functional initiator system, the change of chain length is larger than that in the di‐functional initiator system. At a higher temperature (230°C), the observation is reversed. The molecular weight reduction increases with initiator concentration level for the tetra‐functional initiator, while the di‐functional initiator causes larger reduction in the molecular weight without any obvious relation to the initiator concentration level. Rheological measurements show results consistent with those from gel permeation chromatography (GPC). The observations are explained based on the competition between chain scission and chain extension caused by the single and multiple radicals generated from the initiators. No evidence of architectural change in the CRPP molecules such as branching and crosslinking has been observed in both GPC and rheological measurements. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Cohesin diversity revealed by the crystal structure of the anchoring cohesin from Ruminococcus flavefaciens
Authors: Alber Orly , Noach Ilit , Rincon Marco T. , Flint Harry J. , Shimon Linda J. W. , Lamed Raphael , Frolow Felix , Bayer Edward A.
Published: May 2009

The cellulosome is an intriguing multienzyme complex found in cellulolytic bacteria that plays a key role in the degradation of plant cell‐wall polysaccharides. In Ruminococcus flavefaciens, a predominant fiber‐degrading bacterium found in ruminants, the cellulosome is anchored to the bacterial cell wall through a relatively short ScaE scaffoldin. Determination of the crystal structure of the lone type‐III ScaE cohesin from R. flavefaciens (Rf‐CohE) was initiated as a part of a structural effort to define cellulosome assembly. The structure was determined at 1.95 Å resolution by single‐wavelength anomalous diffraction. This is the first detailed description of a crystal structure for a type‐III cohesin, and its features were compared with those of the known type‐I and type‐II cohesin structures. The Rf‐CohE module folds into a nine‐stranded β‐sandwich with jellyroll topology, typically observed for cohesins, and includes two β‐flaps in the midst of β‐strands 4 and 8, similar to the type‐II cohesin structures. However, the presence in Rf‐CohE of an additional 13‐residue α‐helix located between β‐strands 8 and 9 represents a dramatic divergence from other known cohesin structures. The prominent α‐helix is enveloped by an extensive N‐terminal loop, not observed in any other known cohesin, which embraces the helix presumably enhancing its stability. A planar surface at the upper portion of the front face of the molecule, bordered byβ‐flap 8, exhibits plausible dimensions and exposed amino acid residues to accommodate the dockerin‐binding site. Proteins 2009. © 2009 Wiley‐Liss, Inc.
Soil‐less bioassays for early screening for resistance to imazapyr in sunflower (Helianthus annuus L.)
Authors: Vega Tatiana , Breccia Gabriela , Nestares Graciela , Mayor María Laura , Zorzoli Roxana , Picardi Liliana
Published: May 2009

BACKGROUND: Rapid and efficient diagnostic tests for early screening of herbicide resistance are convenient alternatives to field screening methods. There is a need for a quick, reliable and cost‐effective method for rapid diagnosis of imidazolinone resistance in sunflower (Helianthus annuus L.).

RESULTS: Two seed germination bioassays were developed. Seeds from three sunflower inbred lines differing in resistance to imidazolinones were germinated either on solid culture medium or placed in plastic pots filled with commercial perlite. After 8 days incubation under controlled conditions, both assays successfully distinguished susceptible genotype from the resistant and intermediate ones. The susceptible genotype showed arrested root growth at all herbicide treatments (root length < 1 cm). The resistant genotype developed a complete root system even when exposed to the highest dose of herbicide. However, no definite differences were observed for the intermediate and resistant genotypes with respect to root growth under the different herbicide treatments.

CONCLUSION: The simple and rapid screening assays described in the present study were useful in discriminating imidazolinone resistance at the seedling stage. Therefore, these bioassays could be potential tools for early screening of imidazolinone resistance genes from large sunflower populations. Copyright © 2009 Society of Chemical Industry
Quercetin inhibited murine leukemia WEHI‐3 cells in vivo and promoted immune response
Authors: Yu Chun‐Shu , Lai Kuang‐Chi , Yang Jai‐Sing , Chiang Jo‐Hua , Lu Chi‐Cheng , Wu Chang‐Lin , Lin Jing‐Pin , Liao Ching‐Lung , Tang Nou‐Ying , Wood W. Gibson , Chung Jing‐Gung
Published: May 2009

Enhanced flavonoid consumption is closely related with a reduced cancer incidence as shown in epidemiological studies. Quercetin (3,5,7,3′,4′‐pentahydroxylflavone) is one of the active components of flavonoids which exist in natural plants, particularly in onions and fruits. It was reported that quercetin induced apoptosis in human cancer cell lines, including human leukemia HL‐60 cells, but there is no available information as to its effects on leukemia cells in vivo. The purpose of the present studies was to focus on the in vivo effects of quercetin on leukemia WEHI‐3 cells. The effects of quercetin on WEHI‐3 cells injected into BALB/c mice were examined. Quercetin decreased the percentage of Mac‐3 and CD11b markers, suggesting that the differentiation of the precursors of macrophages and T cells was inhibited. There was no effect on CD3 levels but increased CD19 levels. Quercetin decreased the weight of the spleen and liver compared with the olive oil treated animals. Quercetin stimulated macrophage phagocytosis of cells isolated from peritoneum. Quercetin also promoted natural killer cell activity. Based on pathological examination, an effect of quercetin was observed in the spleen of mice previously injected with WEHI‐3 cells. Apparently, quercetin affects WEHI‐3 cells in vivo. Copyright © 2009 John Wiley & Sons, Ltd.
Quantized average consensus via dynamic coding/decoding schemes
Authors: Carli Ruggero , Bullo Francesco , Zampieri Sandro
Published: May 2009

In the average consensus a set of linear systems has to be driven to the same final state, which corresponds to the average of their initial states. This mathematical problem can be seen as the simplest example of coordination task. In fact it can be used to model both the control of multiple autonomous vehicles which all have to be driven to the centroid of the initial positions, and to model the decentralized estimation of a quantity from multiple measure coming from distributed sensors. This contribution presents a consensus strategy in which the systems can exchange information among themselves according to a fixed strongly connected digital communication network. Beside the decentralized computational aspects induced by the choice of the communication network, we here have also to face the quantization effects due to the digital links. We here present and discuss two different encoding/decoding strategies with theoretical and simulation results on their performance. Copyright © 2009 John Wiley & Sons, Ltd.
Treatment recommendations in long‐chain fatty acid oxidation defects: consensus from a workshop
Authors: Spiekerkoetter U. , Lindner M. , Santer R. , Grotzke M. , Baumgartner M. R. , Boehles H. , Das A. , Haase C. , Hennermann J. B. , Karall D. , de Klerk H. , Knerr I. , Koch H. G. , Plecko B. , Röschinger W. , Schwab K. O. , Scheible D. , Wijburg F. A. , Zschocke J. , Mayatepek E. , Wendel U.
Published: May 2009

Published data on treatment of fatty acid oxidation defects are scarce. Treatment recommendations have been developed on the basis of observations in 75 patients with long‐chain fatty acid oxidation defects from 18 metabolic centres in Central Europe. Recommendations are based on expert practice and are suggested to be the basis for further multicentre prospective studies and the development of approved treatment guidelines. Considering that disease complications and prognosis differ between different disorders of long‐chain fatty acid oxidation and also depend on the severity of the underlying enzyme deficiency, treatment recommendations have to be disease‐specific and depend on individual disease severity. Disorders of the mitochondrial trifunctional protein are associated with the most severe clinical picture and require a strict fat‐reduced and fat‐modified (medium‐chain triglyceride‐supplemented) diet. Many patients still suffer acute life‐threatening events or long‐term neuropathic symptoms despite adequate treatment, and newborn screening has not significantly changed the prognosis for these severe phenotypes. Very long‐chain acyl‐CoA dehydrogenase deficiency recognized in neonatal screening, in contrast, frequently has a less severe disease course and dietary restrictions in many patients may be loosened. On the basis of the collected data, recommendations are given with regard to the fat and carbohydrate content of the diet, the maximal length of fasting periods and the use of l‐carnitine in long‐chain fatty acid oxidation defects.
Perceptions of Licensure: A Survey of Michigan Genetic Counselors
Authors: Mester Jessica L. , Trepanier Angela M. , Harper Cheryl E. , Rozek Laura S. , Yashar Beverly M. , Uhlmann Wendy R.
Published: May 2009

This study by the Michigan Genetic Counselor Licensure Committee is the first known published documentation of genetic counselors’ beliefs and attitudes about licensure. The response rate from genetic counselors in Michigan was 66% (41/62). Ninety‐five percent of respondents were supportive of licensure. Respondents believed licensure would legitimize genetic counseling as a distinct allied healthcare profession (97.5%), increase the public's protection (75%), and allow genetic counselors to practice independently (67%). While 45% felt licensure would increase counselor involvement in lawsuits, this did not impact licensure support (p = 0.744). Opinions were split regarding physician supervision and ordering tests. Even though 28% favored physician supervision, there was overwhelming support for genetic counselors performing some components of genetic testing (95%) and ordering some types of genetic tests (82%) independent of a physician. Use of this survey may be helpful in other states to assess genetic counselors’ interest in licensure and for drafting legislation.
The origin of the Westernized vernacular Chinese baihuawen: A re-evaluation of the influence of Western missionaries on Chinese literature
Authors: Jin YUAN
Published: May 2009

The New Literature (xin wenxue 新文学), can be dated to modern China of the 19th century, when missionaries from the West wrote their own poems, essays and stories in a sort of European-styled vernacular Chinese known as the ouhua baihua 欧化白话 (Europeanized vernacular written language), different from the gu baihua 古白话 (“old” or antique vernacular). Western missionaries were part of the language modernization campaigns during the Late Qing and the May Fourth Movement (1919). They also participated in the New Fiction (xin xiaoshuo 新小说) and National Salvation by Literature (wenxue jiuguo lun 文学救国论) movements and exerted considerable influence upon modern Chinese literature. Their contribution used to be ignored or underestimated by a restricted perspective of inquiry, which should have been corrected by now.
An audible China: Speech and the innovation in modern Chinese writing
Authors: Pingyuan CHEN
Published: May 2009

The image of an “audible China” is one opposed to the traditional China’s as “voiceless.” Not only does it refer to the survival of modern Chinese out of the abandoned Classical Chinese, it also provides a new means to examine modern China’s cultural transformation and development in terms of “voice.” This essay will discuss mainly how speech, one of “the three best tools for spreading civilization,” together with newspapers and magazines and schools, contributes to the success of the Vernacular Chinese Movement (Baihuawen yundong 白话文运动, CE 1917–1919) and the innovation in modern Chinese writing (including Chinese academic writing style).
Correlation Between Wettability and Cleanability of Polyester Fabrics Modified by a Soil Release Polymer and Their Topographic Structure
Authors: Badrul Hasan M. M. , Calvimontes Alfredo , Dutschk Victoria
Published: May 2009

In this study, it was found that images scanned by a non‐contact optical instrument for topographic characterisation based on the principle of chromatic aberration give sufficient information to know the exact location of soil release polymer (SRP) deposition over fabrics. Through the comparison of reflected luminous intensity histograms, it is possible to determine mathematically the zones of fabric on which the SRP molecules settle. For this study, two plain weave fabrics were manufactured in a needle band weave machine from polyethylene terephthalate (PET) filament yarns made from two different cross‐sectional shaped filaments, circular and cruciform. Both the fabrics were desized and heat‐set. Topographic characteristics of polyester fabrics were determined by the optical instrument before and after their impregnation with a SRP. Differences between soiling behaviour, cleanability and wettability of the fabrics before and after impregnation were revealed and discussed. It was verified that micro‐topography of textiles determines the amount of SRP and its location. The results obtained correlate well with the wetting behaviour and cleanability of the fabrics studied.
Viscosity Adjustment of Aqueous Micellar Solutions of Gemini Surfactants by Interaction with Additional Surfactants
Authors: Liu Jinyan , Zhao Jianxi
Published: May 2009

The viscosity of aqueous micellar solutions depends on the size and shape of the aggregates and thus can be adjusted by addition of another surfactant interacting with the original component, which alters the geometry of the molecule‐pair consisting of two surfactants and influences strongly the size and shape of the mixed micelles. Ethanediyl‐α,ω‐bis(dimethyl dodecyl ammonium bromide), referred to as C12‐2‐C12·2Br, forms generally large micelles. Addition of a cationic surfactant (dodecyltrimethylammonium bromide, C12TMABr) or a nonionic surfactant (alkyl polyoxyethylene ether, CmEn), the mixed micelle size is reduced violently since the electrostatic repulsion between the same charged heads of C12‐2‐C12·2Br and C12TMABr or the steric hindrance of the PEO chain of CmEn in the palisade layers of the mixed micelle, which leads to a decrease in the packing parameter P of the molecule‐pair. As a result, the zero‐shear viscosity (η0) of the mixed solution reduces rapidly. In contrast, on adding an oppositely charged surfactant, η0 of the mixed solution increases strongly since the P of the molecule‐pair increases through electrostatic attraction between the oppositely charged heads. The typical cases occur in the mixtures of the anionic gemini surfactant, O,O′‐bis(sodium 2‐lauricate)‐p‐benzenediol C11pPHCNa, and the cationic surfactant C12‐2‐C12·2Br, C12TMABr or its homologue with a different size of heads.
Association betweentrans-fatty acids in erythrocytes and pro-atherogenic lipid profiles among Canadian Inuit of Nunavik: possible influences of sex and age
Authors: Counil Emilie , Julien Pierre , Lamarche Benoit , Château-Degat Marie-Ludivine , Ferland Annie , Dewailly Eric
Published: May 2009

Dietary exposure totrans-fatty acids (TFA) is likely to be high among Canadian Inuit; yet no data are available on the physiological effects of TFA in this population. The purpose of the present study was to assess the association between TFA and plasma lipid profiles in Inuit men and women living in Nunavik (Québec, Canada). In a cross-sectional, population-based survey, a total of 795 Nunavik Inuit eligible participants gave a blood sample. Exposure to TFA was assessed by their relative proportion in erythrocyte membrane. We performed multiple regression analysis using plasma lipids or their linear combinations as the dependent variables and TFA as the main predictor, adjusting for potential confounders. The associations varied markedly between the sexes and according to age. In men (n357, aged 36·3 (sd14·3) years, TFA 1·24 (sd0·54) %), TFA tended to be negatively associated with HDL-cholesterol (HDL-C), apoA1 and LDL particle size, and positively associated with non-HDL-C, LDL-cholesterol (LDL-C), apoB100, the apoB100:apoA1 ratio and the ratios of total cholesterol (TC), LDL-C and TAG to HDL-C. No such trends were observed in women (n438, aged 37·0 (sd14·1) years, TFA 1·16 (sd0·54) %), except for HDL-C and apoA1 in women aged 50 years and more. These results suggest that TFA could raise the risk of CHD in Inuit men at least through their physiological effects on plasma lipids. The differential associations reported in pre- and postmenopausal women need to be reproduced in other populations and in experimental studies addressing the influence of sex hormones in response to dietary fats.
Obesity and chronic disease: always offender or often just accomplice?
Authors: Egger Garry , Dixon John
Published: May 2009

Over a decade ago, the finding of a form of low-grade systemic inflammation (‘metaflammation’) associated with obesity, insulin resistance and chronic disease proffered a causal explanation for the latter. However, recent work has shown that metaflammation is also associated with several modern lifestyle-related and environmental inducers, with or without obesity. Here, we present accumulating data to show a link between metaflammation and a number of non-microbial environmental and lifestyle stimulants, both with and without obesity. This implies that obesity may often be an accomplice to, as much as an offender in, major metabolic disease. The real (albeit distal) cause of such a disease appears to lie in aspects of the modern techno-industrial environment driving unhealthy lifestyle behaviours. If true, this suggests that while individual weight loss may be a component of chronic disease management, it may be neither ‘necessary’ nor ‘sufficient’ to reduce the problem at a population level. Greater multidisciplinary and policy input is needed to modify the economic and political drivers of the modern, obesogenic environment.
Effect of moderate intakes of different tea catechins and caffeine on acute measures of energy metabolism under sedentary conditions
Authors: Gregersen Nikolaj T. , Bitz Christian , Krog-Mikkelsen Inger , Hels Ole , Kovacs Eva M. R. , Rycroft Jane A. , Frandsen Erik , Mela David J. , Astrup Arne
Published: May 2009

Green tea may stimulate energy metabolism; however, it is unclear if acute effects are caused by specific catechins, caffeine or their combination. The objective of the present study was to examine the separate and combined effects of different catechins and caffeine on energy expenditure (EE) and fat oxidation over a single day. Fifteen healthy, normal-weight males received capsules containing placebo, caffeine alone (150 mg), or caffeine plus a catechin mixture (600 mg) enriched in either epigallocatechin-3-gallate (EGCG), epigallocatechin or a mix of catechins, in a randomised cross-over double-blinded design. On each test day EE, respiratory quotient (RQ) and substrate oxidation were measured under sedentary conditions in a respiratory chamber for 13·5 h. We found no significant treatment effect on EE (P = 0·20) or RQ (P = 0·68). EGCG with caffeine insignificantly raised EE and fat oxidation v. caffeine-only and placebo (EE 5·71 (se 0·12) v. 5·68 (se 0·14) v. 5·59 (se 0·13) MJ/12·5 h, respectively; fat oxidation 84·8 (se 5·2) v. 80·7 (se 4·7) v. 76·8 (se 4·0) g/12·5 h). Catechin/caffeine combinations at these dosages and mode of application had non-significant acute effects on EE and fat oxidation. The maximum observed effect on EE of about 2 % could still be meaningful for energy balance over much longer period of exposure. However, higher short-term effects reported in the literature may reflect variations in green tea extracts, added caffeine, or synergies with physical activity. The specific mechanisms and conditions that may underpin observed longer-term benefits of catechin-enriched green tea consumption on body composition remain to be confirmed.
The distribution of the residues of a quartic polynomial
Authors: McCann K. , Williams K. S.
Published: May 2009

Let f(x) denote a polynomial of degree d defined over a finite field k with q = pnelements. B. J. Birch and H. P. F. Swinnerton-Dyer [1] have estimated the number N(f) of distinct values of y in k for which at least one of the roots of

is in k. They prove, using A. Weil's deep results [12] (that is, results depending on the Riemann hypothesis for algebraic function fields over a finite field) on the number of points on a finite number of curves, that

where λ is a certain constant and the constant implied by the O-symbol depends only on d. In fact, if G(f) denotes the Galois group of the equation (1.1) over k(y) and G+(f) its Galois group over k+(y), where k+ is the algebraic closure of k, then it is shown that λ depends only on G(f), G+(f) and d. It is pointed out that “in general”
Hilbert transforms and unitary equivalence
Authors: Putnam R.
Published: May 2009

If E is a subset of the real line of positive measure, then the associated Hilbert transform H = HE,

where the integral is a Cauchy principal value, is a bounded self-adjoint operator on L2(E) (cf. Muskhelishvili [4]). In case E = (-∞, ∞) the transformation is also unitary with a spectrum consisting of 1 and -1, each of infinite multiplicity (Titchmarsh [10]). If E is a inite interval the spectral representation of H has been given by Koppelman and Pincus [3]; see also Putnam [6]. In particular the spectrum of H is in this case the closed interval [-1, 1]. Moreover, according to Widom [11], the spectrum of H is [-1, 1] whenever E ≠ (-∞, ∞), that is, whenever
On products of idempotent matrices
Authors: Erdos J. A.
Published: May 2009

In [1], J. M. Howie considered the semigroup of transformations of sets and proved (Theorem 1) that every transformation of a finite set which is not a permutation can be written as a product of idempotents. In view of the analogy between the theories of transformations of finite sets and linear transformations of finite dimensional vector spaces, Howie's theorem suggests a corresponding result for matrices. The purpose of this note is to prove such a result.
On the nonexistence of Lp solutions of certain nonlinear differential equations
Authors: Hallam Thomas G.
Published: May 2009

The asymptotic behavior of the solutions of ordinary nonlinear differential equations will be considered here. The growth of the solutions of a differential equation will be discussed by establishing criteria to determine when the differential equation does not possess a solution that is an element of the space Lp(0, ∞)(p ≧ 1).
Regular ω-semigroups
Authors: Munn W. D.
Published: May 2009

Let S be a semigroup whose set E of idempotents is non-empty. We define a partial ordering ≧ on E by the rule that e ≧ f and only if ef = f = fe. If E = {ei: i∈ N}, where N denotes the set of all non-negative integers, and if the elements of E form the chain

then S is called an ω-semigroup.
A note on the duality of locally compact groups
Authors: Baker J. W.
Published: May 2009

Let H be a group of characters on an (algebraic) abelian group G. In a natural way, we may regard G as a group of characters on H. In this way, we obtain a duality between the two groups G and H. One may pose several problems about this duality. Firstly, one may ask whether there exists a group topology on G for which H is precisely the set of continuous characters. This question has been answered in the affirmative in [1]. We shall say that such a topology is compatible with the duality between G and H. Next, one may ask whether there exists a locally compact group topology on G which is compatible with a given duality and, if so, whether there is more than one such topology. It is this second question (previously considered by other authors, to whom we shall refer below) which we shall consider here.
The solution of certain simultaneous pairs of dual integral equations
Authors: Lowengrub M.
Published: May 2009

In the analysis of mixed boundary value problems by Hankel transforms, one often encounters dual integral equations of the form

where I1 = (0, 1), I2 = (1, ∞); w1(x), w2(x) are weight functions, ψ(x) is the unknown function, and f(y), g(y) are functions continuously differentiate on I1 and I2 respectively. Many successful attempts have been made to solve (1.1) and (1.2). These are all discussed in a recent book by Sneddon [7]. As pointed out in a recent paper by Erdogan and Bahar [4], in mixed boundary value problems of semi-infinite domains involving more than one unknown function such as those arising in elastostatics, viscoelasticity, and electrostatics, the formulation will lead to a system of simultaneous dual integral equations which is a generalization of (1.1) and (1.2). These equations may be expressed as follows:

with i = 1, 2, …, n, where we use the notation
A Bessel function inequality connected with stability of least square smoothing, II
Authors: Lorch Lee , Szego Peter
Published: May 2009

In accordance with customary notation, Jv(t) denotes the Bessel function of the first kind and order v, jvk its kth positive zero and jv, 0 = 0.

The object of this note is to prove that
The order problem and the power problem for free product sixth-groups
Authors: McCool James
Published: May 2009

Let G be a group given in terms of generators and denning relations. The order problem is said to be solvable for (the given presentation of) the group G if, given any element W of G (as a word in the given generators of G), we can determine the order of W in G. The power problem is solvable for G if, given any pair X, Y of elements of G, we can determine whether or not X belongs to the cyclic subgroup {Y} of G generated by Y. It is easy to see that if either of these problems is solvable for G, then the word problem is also solvable for G.
On the second natural representation of the symmetric groups
Authors: Peel M. H.
Published: May 2009

In [1], the natural representation module of the symmetric groups, hereafter called the first natural representation module of the symmetric groups, was analysed. It is the purpose of this paper to analyse the second natural representation module of the symmetric groups.
-injectors of locally soluble FC-groups
Authors: Tomkinson M. J.
Published: May 2009

A group G is said to be an FC-group if each element of G has only a finite number of conjugates in G. We are concerned with the class of periodic locally soluble. FC-groups. Clearly subgroups and factor groups of -groups are also -groups.

Every finite soluble group is a -group, and we consider here the generalization of a concept from the theory of finite soluble groups.
A note on the thermoelastic problem for a penny-shaped crack
Authors: Tweed John
Published: May 2009

1. The problem of determining the state of stress in the vicinity of a penny-shaped crack which is opened by thermal means has been considered by Olesiak and Sneddon [1]. In that paper no simple closed expressions were given either for the stress-intensity factor at the tip of the crack or for the normal component of the surface displacement. The purpose of this note is to show how such expressions may be derived.
On inequalities for integral operators
Authors: Okikiolu G. O.
Published: May 2009

In two papers [3] and [4], the author has extended the inequality of Schur (Theorem 319 of [2]) to cases involving kernels which satisfy identities of the form

The purpose of this paper is to prove a general inequality, which includes the above and also the inequality of Young (Theorem 281 of [2]) as special cases. We shall give the results a general setting by considering functions defined on abstract measure spaces. From this we shall deduce an extension to n dimensions of the results given in [3], which also generalises a similar extension of the Schur inequality given by Stein and Weiss. In fact some cases of the other results given in [5] will follow directly from our theorem.
A concavity problem in number theory
Authors: Anderson Ian
Published: May 2009

For any fixed value of x, let denote the set of all positive integers with exactly k prime factors counted according to multiplicity, each prime factor being ≦ x. In an earlier paper [1] in this journal we posed the following problem. Let

Show the existence or non-existence of an integer K such that, if

then

We now show that such a K exists, and that in (2) there is strict inequality in each case.
Maximal homomorphic images of commutative semigroups
Authors: McAlister D. B. , O'Carroll L.
Published: May 2009

In this paper we give necessary and sufficient conditions on a commutative semigroup in order that it should have a maximal homomorphic image of one of the following types: (1) groups, (2) semigroups which are unions of groups and (3) pseudoinvertible semigroups, i. e. semigroups having the property that some power of each element lies in a subgroup of the semigroup.
Homology and the Koszul complex
Authors: Moore D. J.
Published: May 2009

Let R be a commutative ring with an identity element, E a (unitary) R-module, and x1, x2, …, xs elements of R. In these circumstances it is possible to form the Koszul complex† K(x1, x2, …, xs|E) of E with respect to x1, x2,…, xs and to investigate the implications, for E and xl, x2, …, xs, if certain of the homology modules of this complex vanish. This was first undertaken by M. Auslander and D. A. Buchsbaum [1]. Among the many results they obtain, the following [1, Proposition 2.8, p. 632] is of particular interest in connection with the present paper:

If R is Noetherian, E is finitely generated, and x1x2,…, xs belong to the Jacobson radical of R, then the statements

(a) x1, x2,…, xsis an R-sequence on E,

(b) HpK(x1, x2,…,xs⃒E) = O for all p > 0,

(c) H1K(x1, x2,…., xs,⃒E) = 0,

are all equivalent.
Abstract integral spaces and minimal extensions
Authors: Maron M. J.
Published: May 2009

The development of the theory of absolute integrals derives from certain key facts. Among them are:

(I) An integral is a positive linear functional on a vector lattice, which is continuous in a certain sense.

(II) A function equal almost everywhere to a summable function is itself summable.

(III) Every measurable function is the pointwise limit of a sequence of elementary step functions.

A device that often plays an important role in measure theory, but which has not beenfully exploited in the theory of abstract integrals is that of

(IV) the smallest class containing a given class and having a certain property

(such as being a σ-ring of sets). It is our purpose in this paper to examine the theory of abstract real-valued absolute integrals axiomatically, in such a way as to isolate and clarify the roles of (I) through (IV).
A note concerning the L1convergence of a class of games which become fairer with time
Authors: Blake Louis H.
Published: May 2009

Throughout this note, let be a probability space with an increasing sequence of sub σ-fields of whose union generates . Let be a sequence of random variables adapted to (see [3], p. 65) and henceforth be referred to as a game. As in [1], the game will be said to become fairer with time if, for every ε > ε,

as n, m → ∞ with n ≧ m
Discriminantal divisors and binary quadratic forms
Authors: Brown Ezra
Published: May 2009

An ancipital form is a form [a, b, c] in which b= 0 or b= a; these fall into pairs of associates: [a, 0, c] and [c, 0, a] (type 1), and [a, a, c] and [4c–a, 4c–a, c] (type 2). The set of discriminantal divisors of discriminant d is formed by choosing, from each pair of primitive associate ancipital forms of discriminant d, exactly one of the two leading coefficients. In this article we study representations of discriminantal divisors of a given discriminant by binary quadratic forms of that discriminant, previously studied by the author and by G. Pall. We are concerned here with discriminants d= 4kpq, where k ≥ 1, p = 1, q = 3 (mod 4) are primes, and d = 4kp, where k ≥ 1 and p is an odd prime. This investigation arose in connection with the search for integral solutions of x2 –Dy2 = – 1.
Square roots in Banach *-algebras
Authors: Bonsall F. F. , Stirling D. S. G.
Published: May 2009

We give a simple proof of the lemma of Ford [1] on the existence of self-adjoint square roots in Banach*-algebras in which continuity of the involution is not assumed.
On the semigroup of differentiable mappings (II)
Authors: Wood G. R. , Yamamuro Sadayuki
Published: May 2009

In [2], K. D. Magill, Jr. has proved that every automorphism of the semigroup (with respect to composition) of all real-valued differentiable functions of a real variable is inner. The purpose of this paper is to generalize this fact to arbitrary finite-dimensional real Banach spaces.
Asymptotic formulae for linear equations
Authors: Hinton Don B.
Published: May 2009

Numerous formulae have been given which exhibit the asymptotic behaviour as t → ∞solutions of

where F(t) is essentially positive and Several of these results have been unified by a theorem of F. V. Atkinson [1]. It is the purpose of this paper to establish results, analogous to the theorem of Atkinson, for the third order equation

and for the fourth order equation