bluuebunny/crossref_metadata_2025 huggingface dataset:
An English Assessment of Scotland's Education Spending Needs
Authors: KING DAVID , PASHLEY MATTHEW , BALL ROB
Published: March 2005

Scotland has much higher public expenditure per head than England, but little work has been done to compare Scottish and English needs. We compare their needs for school education, and we show that if the Formula Spending Share approach that is used to estimate English local authorities' needs were applied in Scotland, then Scotland would be found to need about 3 per cent more per pupil than England; however, this English approach may slightly underestimate Scotland's needs. We also show that the Grant Aided Expenditure approach that is actually used to estimate Scottish local authorities' needs may be about 7 per cent more generous than the English approach. Finally, we find that the correlation between the relative education needs for different authorities as assessed by the Scottish approach and their relative needs as assessed by the English approach is only modest; this implies that there may be serious shortcomings in at least one approach.
Development of C/C–SiC Brake Pads for High‐Performance Elevators
Authors: Abu El‐Hija Hussam , Krenkel Walter , Hugel Stefan
Published: March 2005

Novel C/C–SiC materials have been developed for their use as brake pads for high‐speed elevators. Under dynamic and stationary conditions, these materials exhibit high thermal shock resistance, high coefficients of friction, and extremely low wear rates. In addition, it has been found that the SiC content of the C/C–SiC materials on the friction surface heavily influences the frictional behavior. Low‐cost materials based on short fiber reinforcement and on drastically reduced process times showed their high potential for the manufacture of cost‐efficient brake pads.
Metamodel-Driven Design Optimization Using Integrative Graphical Design Interfaces: Results From a Job-Shop Manufacturing Simulation Experiment
Authors: Ligetti Christopher B. , Simpson Timothy W.
Published: March 2005

Today, engineers are relying more on modern computer tools and techniques to visualize complex data sets; however, few studies have examined the effect of fast, graphical design interfaces on user performance during system design. The objective in this paper is to extend our previous findings in this area by examining the impact of fast, graphical design interfaces on design efficiency and design effectiveness within the context of a job-shop design problem. We accomplish this by investigating the effect of an artificial response delay, intended to mimic computationally intensive analyses, on user performance. Experimental results indicate that user performance deteriorates significantly when a small response delay of 1.5 s is introduced: percent error and task completion time increase, on average, by 9.4% and 81 s, respectively, when the delay is present. The use of first-order, stepwise, and second-order polynomial regression models for approximating the system responses (outputs) is also investigated, and user performance is found to improve when stepwise polynomial regression models are used instead of first- or second-order models. The stepwise models yielded 12% lower error and 91 s faster completion times, on average, over the first-order models; error was 13.5% lower and completion time was 62 s faster, on average, than when second-order models were used. The results confirm our previous findings about the negative impact of response delay on task completion time while demonstrating that delay can also significantly decrease the efficacy of a metamodel-driven graphical design interface.
Interactive Reduct Evolutional Computation for Aesthetic Design
Authors: Yanagisawa Hideyoshi , Fukuda Shuichi
Published: March 2005

We propose a method of evolving designs based on the user’s personal preferences. The method works through an interaction between the user and a computer system. The method’s objective is to help the customer to set design parameters via a simple evaluation of displayed samples. An important feature is that the design attributes to which the user pays more attention (favored features) are estimated using reducts in rough set theory and reflected when refining the design. New design candidates are generated by the user’s evaluation of design samples generated at random. The values of attributes estimated as favored features are fixed in the refined samples, while other attributes are generated at random. This interaction continues until the samples converge to a satisfactory design. In this manner, the design process efficiently evaluates personal and subjective preferences. The method is applied to design a 3D cylinder model such as a cup or vase. The method is then compared with an Interactive GA.
Standardization of the Finite Element Analysis Data-Exchange in Aeronautics Concurrent Engineering
Authors: Charles Se´bastien , Eynard Benoı^t , Bartholomew Peter , Paleczny Christian
Published: March 2005

The paper presents some research and a business case study carried out in a European project focused on Concurrent Engineering and the implementation of data exchange standards in the aeronautics industry. It deals with the use of the STEP AP209 standard dedicated to the exchange of finite element analysis data. Applied in the context of Concurrent Engineering within the extended enterprise, the STEP AP209 standard should enhance the communication, exchange, and sharing of product data between mechanical engineering and analysis experts across distributed sites. The development of a translator from STEP AP209 to SAMCEF (commercial FE solver) has been carried out and evaluated on an aircraft engine component.
ENERGY-EFFICIENT NODE SCHEDULING MODELS IN SENSOR NETWORKS WITH ADJUSTABLE RANGES
Authors: WU JIE , YANG SHUHUI
Published: March 2005

In this paper, we study the problem of maintaining sensing coverage by keeping a small number of active sensor nodes and using a small amount of energy consumption in wireless sensor networks. This paper extends a result from22where only uniform sensing range among all sensors is used. We adopt an approach that allows non-uniform sensing ranges for different sensors. As opposed to the uniform sensing range node scheduling model in22, two new energy-efficient models with different sensing ranges are proposed. Our objective is to minimize the overlapped sensing area of sensor nodes, thus to reduce the overall energy consumption by sensing and communication to prolong the whole network's life time, and at the same time to achieve the high ratio of coverage. Extensive simulation is conducted to verify the effectiveness of our node scheduling models.
CANONICAL DECOMPOSITION, REALIZER, SCHNYDER LABELING AND ORDERLY SPANNING TREES OF PLANE GRAPHS
Authors: MIURA KAZUYUKI , AZUMA MACHIKO , NISHIZEKI TAKAO
Published: March 2005

A canonical decomposition, a realizer, a Schnyder labeling and an orderly spanning tree of a plane graph play an important role in straight-line grid drawings, convex grid drawings, floor-plannings, graph encoding, etc. It is known that the triconnectivity is a sufficient condition for their existence, but no necessary and sufficient condition has been known. In this paper, we present a necessary and sufficient condition for their existence, and show that a canonical decomposition, a realizer, a Schnyder labeling, an orderly spanning tree, and an outer triangular convex grid drawing are notions equivalent with each other. We also show that they can be found in linear time whenever a plane graph satisfies the condition.
BULK PHANTOM FIELDS, INCREASING WARP FACTORS AND FERMION LOCALIZATION
Authors: KOLEY RATNA , KAR SAYAN
Published: March 2005

A bulk phantom scalar field (with negative kinetic energy) in a sine–Gordon type potential is used to generate an exact thick brane solution with an increasing warp factor. It is shown that the growing nature of the warp factor allows the localization of massive as well as massless spin-1/2 fermions on the brane even without any additional non-gravitational interactions. The exact solutions for the localized massive fermionic modes are presented and discussed. The inclusion of a fermion–scalar Yukawa coupling appears to change the mass spectrum and wave functions of the localized fermion though it does not play the crucial role it did in the case of a decreasing warp factor.
Professional Employer Organizations and Their Impact on Client Satisfaction With Human Resource Outcomes: A Field Study of Human Resource Outsourcing in Small and Medium Enterprises
Authors: Klaas Brian S. , Gainey Thomas W. , McClendon John A. , Yang Hyuckseung
Published: March 2005

Increasingly, small and medium enterprises are outsourcing human resource (HR) activities to professional employer organizations (PEOs). The authors draw on social network theory, transaction cost economics, and social exchange theory to examine how PEO and client characteristics moderate the impact associated with outsourcing human capital-enhancing HR services. Results from a study suggest that using a PEO for human capital-enhancing services was positively related to HR outcomes and that this relationship was stronger when a weak-ties service delivery model was used, client receptivity was high, and the PEO contract was more detailed.
Gender and Science Where Science Is on the Margins
Authors: Koblitz Ann Hibner
Published: March 2005

Historians of science have traditionally concentrated on the achievements of scientists in Western Europe and North America. The usual assumption was that one did not need to study scientific communities outside of a few key countries because they were presumed to be analogous to (though weaker than) scientific communities in the West. In general, those who study women in science have shared this bias. This article provides examples that illustrate how cross-national research that includes less-studied areas of the world can move us beyond generalizations that are based on small samples of women scientists in relatively few countries. This article is not definitive but rather suggests ways in which transnational studies of gender and science can contribute to our knowledge of not only the position of women in science but also the significance of class and social status and the meanings attached to the scientific enterprise in different cultural contexts.
A Failing Grade for the German End-of-Life Vehicles Take-Back System
Authors: Nakajima Nina , Vanderburg Willem H.
Published: March 2005

The German end-of-life vehicle take-back system is described and analyzed in terms of its impact on the environment and the car companies involved. It is concluded that although this system is often cited as an example of a successful take-back scheme, it is not one that maximizes the value recovered from end-of-life vehicles. As a result, corporations do not achieve the potential benefits that can be realized from an alternate value chain based on recovering value from end-of-life products. Neither is society benefiting from the potential reduction in pollution and from making its way of life more sustainable. Without bringing these potential benefits to all stakeholders, the system is not likely to have a future.
Giant wood spider Nephila pilipes alters silk protein in response to prey variation
Authors: Tso I-Min , Wu Hsuan-Chen , Hwang In-Ru
Published: March 2005

Recent studies have demonstrated that orb-weaving spiders may alter web structures, foraging localities or silk output in response to prey variations. In this study we conducted field surveys and food manipulations to examine whether orb-weaving spiders may also adjust the protein of silk to prey variations. A comparison of dragline silks collected from nine giant wood spider Nephila pilipes populations in Taiwan showed a spatial variation. The percentage of all amino acids (except alanine and glycine)exhibited significant differences among populations. A survey of prey composition also revealed a significant spatial variation among N. pilipes populations. To determine whether prey variation was responsible for silk protein variation, we fed N. pilipes with different types of prey (dipteran vs orthopteran) then compared the percentage of five major dragline amino acids and secondary structures. The results showed that dragline of N. pilipes fed with orthopteran prey contained significantly higher proline and glutamine but lower alanine. Congruent with this result were those from FTIR spectroscopy, which showed that dragline of N. pilipes fed with crickets exhibited significantly higher percentage of proline- and glutamine-containing β turns, and lower percentage of alanine-containing β sheet structures. Since the results of feeding manipulations showed that diet significantly affected the compositions of dragline silks, the observed spatial variation seemed to reflect the different types of prey these spiders had consumed. Results of this study thus indicated that orb-weaving spiders can alter dragline protein in response to prey variations.
Direct calorimetry reveals large errors in respirometric estimates of energy expenditure
Authors: Walsberg Glenn E. , Hoffman Ty C.M.
Published: March 2005

Knowledge of animal energetics is based largely upon indirect calorimetry,which is estimation of metabolic heat production by an organism from measurement of indices such as oxygen consumption or carbon dioxide production. Remarkably, indirect calorimetry has been validated by comparison to direct measurements of metabolic heat production (direct calorimetry) only for highly restricted conditions, primarily with a few species of medium-to-large mammals. Taxa with differing physiologies are little studied. For birds, for example, validations are limited to chickens and waterfowl exposed to mild environmental conditions and typically fasted for prolonged periods. Workers rely upon these restricted validations when studying animals ranging greatly in activity, phylogeny, body size and nutritional status. We tested the accuracy of respirometric estimates of energy expenditure by simultaneous indirect and direct calorimetry in a small mammal (the kangaroo rat Dipodomys merriami Mearns), a small bird (the dove Columbina inca Lesson) and a medium-sized bird (the quail Coturnix communis Linnaeus). We find that conventional respirometric estimates of energy expenditure may incorporate large errors (up to 38%) that are sufficient to call into question generalizations regarding patterns of animal energy use in many studies.
In vivomuscle functionvsspeed I. Muscle strain in relation to length change of the muscle-tendon unit
Authors: Hoyt Donald F. , Wickler Steven J. , Biewener Andrew A. , Cogger Edward A. , De La Paz Kristin L.
Published: March 2005

The activity of muscles can be concentric (shortening), eccentric(lengthening) or isometric (constant length). When studying muscle function it is important to know what the muscle fascicles are actually doing because the performance of muscle is strongly influenced by the type of activity: force decreases as a function of shortening velocity during concentric contractions;force produced during eccentric contractions can be stronger than maximum isometric force, and force production is enhanced if a concentric contraction follows an eccentric phase. It is well known that length changes of muscle fascicles may be different from length changes of the overall muscle-tendon unit because of the compliance of the series elasticity. Consequently,fascicles of joint extensor muscles may not undergo eccentric activity even when the joint flexes, but the extent to which this occurs may vary with the compliance of the series elasticity and may differ between species: the vastus lateralis, a knee extensor, shortens when active during trotting in dogs and lengthens in rats. Previous studies of kinematics of trotting in horses have shown that during stance, the elbow extends nearly continuously with a brief period of flexion near mid-stance and the knee exhibits two phases of flexion followed by extension. The lateral triceps (an elbow extensor) has no external tendon but the vastus lateralis has a relatively long external tendon and the fascicles insert on an aponeurosis. Thus, one might expect the relation between fascicle strain and overall length change of the muscle-tendon units to be quite different in these two muscles. In the present study in horses,fascicle length changes of the lateral triceps and vastus lateralis were measured with sonomicrometry and length changes of the muscle-tendon units were estimated from muscle architecture and joint kinematics for four horses trotting on a treadmill at nine speeds. Because the focus of this study was the relation between length changes of the muscle-tendon unit (estimated from kinematics) and length changes in the muscle fascicles, we divided the stance-phase sonomicrometry records into phases that corresponded to the alternating flexion and extension of the joint as indicated by the kinematic records. During its one eccentric phase, the triceps shortened by 0.7±0.4% despite a predicted lengthening of 1%. Similarly, the vastus shortened by 3.7±1.9% when kinematics predicted 3.2% lengthening. During their concentric phases the triceps shortened by 10.6% and the vastus shortened by 8.1%. Strain in the triceps did not change with speed but it did in the vastus. Strain rate increased with speed in both muscles as did the integrated EMG, indicating an increase in the volume of muscle recruited. Thus, despite differences in their architecture and the kinematic patterns of the associated joints, these two joint extensors exhibited similar activity.
The role of mineralized tissue in the buffering of lactic acid during anoxia and exercise in the leopard frogRana pipiens
Authors: Warren Daniel E. , Jackson Donald C.
Published: March 2005

To evaluate the role of mineralized tissues of the leopard frog in buffering acid, we analyzed the composition of femur and auditory capsule, the latter of which encloses a portion of the endolymphatic lime sacs, and investigated the extent to which these tissues are involved in buffering lactic acid after 2.5 h of anoxia and 10-19 min of strenuous exercise at 15°C. We analyzed the following tissues for lactate: plasma, heart, liver,gastrocnemius muscle, femur, auditory capsule and carcass. Plasma[Ca2+], [Mg2+], [inorganic phosphate (Pi)],[Na+] and [K+] were also measured. Femur Ca2+, Pi and CO32- compositions were similar to bone in other vertebrates. Auditory capsule had significantly more CaCO3 than femur. Lactate was significantly elevated in all tissues after anoxia and exercise, including femur and auditory capsule. Anoxia increased plasma [Ca2+], [Mg2+], [Pi]and [K+] and had no effect on plasma [Na+]. Exercise increased plasma [Mg2+], [Pi] and [K+] and had no effect on plasma [Ca2+] or [Na+]. The skeleton and endolymphatic lime sacs buffered 21% of the total lactate load during anoxia, and 9% after exercise. The exact contribution of the entire endolymphatic sac system to lactate buffering could not be determined in the present study. We conclude that the mineralized tissues function as buffers during anoxia and exercised induced lactic acidosis in amphibians.
Directionality of the lizard ear
Authors: Christensen-Dalsgaard Jakob , Manley Geoffrey A.
Published: March 2005

Lizards have highly sensitive ears, but most lizard heads are small (1-2 cm in diameter) compared to the wavelengths of sound of frequencies to which they are most sensitive (1-4 kHz, wavelengths 34-8.5 cm). Therefore, the main cues to sound direction that mammals use - binaural time and intensity cues due to arrival-time differences and sound shadowing by the head - will be very small in lizards.

The present work shows that acoustical coupling of the two eardrums in lizards produces the largest directionality of any terrestrial vertebrate ear studied. Laser vibrometric studies of tympanic motion show pronounced directionality within a 1.8-2.4 kHz frequency band around the best frequency of hearing, caused by the interference of ipsi- and contralateral inputs. The results correspond qualitatively to the response of a simple middle ear model,assuming coupling of the tympana through a central cavity. Furthermore,observed directional responses are markedly asymmetrical, with a steep gradient of up to 50-fold (34 dB) response differences between ipsi- and contralateral frontal angles. Therefore, the directionality is easily exploitable by simple binaural subtraction in the brain. Lizard ears are the clearest vertebrate examples of directionality generated by tympanic coupling.
Decomposition of Monolayer Coverage on Gold Nanoparticles by UV/ozone Treatment
Authors: Pang Shufeng , Kurosawa Yousuke , Kondo Takeshi , Kawai Takeshi
Published: March 2005

Au nanoparticles, covered with cationic dichain surfactant on the whole surface, were treated with UV/ozone. FT-IR spectra of the Au nanoparticles with bottom-, upper-, and fully covered surfactant monolayers revealed a variable decomposition rate. The sum frequency generation spectra of the treated nanoparticles showed that the surface coverage of gold nanoparticles lose the centrosymmetric structure, implying asymmetric distribution of the protected surfactant molecules. The UV–vis electronic absorption spectra suggested stable nanoparticle monolayer film structure after UV/ozone irradiation.
Syntheses of Novel Indole Lipoic Acid Derivatives and Their Antioxidant Effects on Lipid Peroxidation
Authors: Gurkan A. Selen , Karabay Arzu , Buyukbingol Zeliha , Adejare Adeboye , Buyukbingol Erdem
Published: March 2005

The aim of the study was to examine antioxidant properties of conjugates based on indole and lipoic acid moieties. The design and syntheses of novel indole α‐lipoic acid derivatives were performed. The antioxidant properties of target compounds were investigated using rat liver microsomal, NADPH‐dependent lipid peroxidation inhibition. Some of the target compounds, especially those containing amide linker at position 5 of indole ring, proved to be highly effective in inhibiting lipid peroxidation as compared to α‐lipoic acid.
Magnetic field inhibits isolated lymphocytes' proliferative response to mitogen stimulation
Authors: Roman Adam , Zyss Tomasz , Nalepa Irena
Published: March 2005

We aimed to find out how the exposure of isolated lymphocytes to a pulsed magnetic field (MF) affected their in vitro proliferative response to mitogenic stimulation. Cells were exposed to MF of various intensities (0.3, 0.6, and 1.2 T) at a constant frequency of 30 Hz, for a period of 60, 180, and 330 s. Then, the proliferative response of splenocytes was induced by optimal concentrations of concanavalin A (Con A; mitogenic toward T cells), bacterial lipopolysaccharide (LPS; mitogenic toward B cells), or pokeweed mitogen (PWM; mitogenic toward both populations). We found that the exposure of lymphocytes to the MF profoundly inhibited their proliferative response to mitogens. The suppressive action of the MF on B and T cell proliferation was intensified when a cooperative response of those two lymphocyte populations was simultaneously induced by PWM. The inhibitory effect of MF depended on the exposure time and MF intensity. Prolonged exposure and/or a stronger intensity of the MF weakened its inhibitory influence on the response of lymphocyte to mitogenic stimulation. The data show that an exposure to MF may influence the activity of lymphocytes in their response to mitogenic stimuli. Bioelectromagnetics 26:201–206, 2005. © 2005 Wiley‐Liss, Inc.
On the significance of the time constants of magnetic field sensitivity in animals
Authors: Fuller Mike , Dobson Jon
Published: March 2005

A variety of organisms is known to have the ability to transduce and respond to relatively weak magnetic fields, including the earth's field. Though biogenic magnetite has been identified as the transducer in a number of cases with regards to geomagnetic field sensing, the mechanism underlying neurophysiological responses in human studies is not understood. Here we note that the time constants involved in this latter type of field sensitivity are much longer than those in organisms that make use of the earth's magnetic field for navigation. The purpose of this brief communication is to suggest that the time constants associated with magnetic field sensitivity may be a useful way to distinguish field sensitivity due to magnetite based receptors from sensitivity that may depend on direct (or downstream) biochemical processes. Bioelectromagnetics 26:234–237, 2005. © 2005 Wiley‐Liss, Inc.
Semi‐analytical computation of 3D stress singularities in linear elasticity
Authors: Mittelstedt C. , Becker W.
Published: March 2005

The boundary finite element method (BFEM (Finite‐Element Modelling of Unbounded Structures. Wiley: Chichester, England, 1996, The Scaled Boundary Finite Element Method. Wiley: Chichester, England, 2003)) is employed for the investigation of the order of stress singularities for several classes of three‐dimensional singular stress concentration problems, namely notch, crack and laminate free‐edge situations. In all cases, the BFEM results agree excellently with reference results. The required computational effort is considerably lower compared to e.g. standard finite element computations and thus establishes the BFEM as a powerful tool for the semi‐analytical modelling of linear elastic solids. Copyright © 2005 John Wiley & Sons, Ltd.
A robust a priori error estimate for the Fortin–Soulie finite element method
Authors: Blacker David J.
Published: March 2005

It is well known that conforming finite element schemes exhibit Poisson locking in the incompressible limit as the Poisson ratio ν tends to 1/2. A remedy for this is to use a non‐conforming method (Math. Comput. 1992; 59:321‐328) in which an a priori error bound is proved for the Crouzeix–Raviart scheme. In this paper we derive a new a priori estimate for the error in energy for the Fortin–Soulie finite element method using a method similar to that used in Brenner and Sung. We then illustrate the new error bound by presenting some numerical examples. Copyright © 2005 John Wiley & Sons, Ltd.
Discrimination in the Solid‐State Photodimerization of 1‐Methyl‐5,6‐diphenylpyrazin‐2‐one
Authors: Kaftory Menahem , Shteiman Vitaly , Lavy Tali , Scheffer John R. , Yang Jie , Enkelmann Volker
Published: March 2005

1‐Methyl‐ and 1‐ethyl‐5,6‐diphenylpyrazin‐2‐one crystallize in two modifications, one of which is light‐stable and the other light‐sensitive. The light‐sensitive modification is known to undergo photodimerization in the solid state. This polymorph crystallizes in the monoclinic space group P21 with two crystallographically independent molecules in the asymmetric unit. The molecules are packed in stacks running parallel to the unique b axis. The two independent molecules are arranged alternately along the stack. In principle, there are two different pairs of molecules within a stack that can undergo photodimerization, and each should form a different enantiomer. A large crystal was irradiated and a solution of the product was separated by HPLC. The optical purity of the (+)‐enantiomer sample was estimated to be greater than 90 %. This finding indicates that only one of the two pairs undergoes photoreaction. The structure of a single crystal of the pyrazinone was elucidated by X‐ray diffractometry before and after irradiation with a laser at a wavelength of 488 nm to 19 % conversion. The results of the crystal‐structure determinations provide additional evidence that only one of the two pairs of molecules undergoes photodimeri‐zation although there are no significant differences between the distances between the reacting centers. Furthermore, the latter results suggest that weak hydrogen bonds are a dominant factor that determines which of the two pairs is dimerized upon irradiation. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Synthesis and Antitumor Activity of the Estrane Analogue of OSW‐1
Authors: Matsuya Yuji , Masuda Seiji , Ohsawa Noriko , Adam Solange , Tschamber Théophile , Eustache Jacques , Kamoshita Keiichi , Sukenaga Yoshikazu , Nemoto Hideo
Published: March 2005

The estrane analogue of OSW‐1, a potent antitumor natural saponin, was efficiently synthesized from estrone in 12 steps. The cytostatic activity of the compound against several human malignant tumor cells was examined and compared to those of the natural OSW‐1 and cisplatin, the results suggesting that the modification of the steroidal component could be an effective approach in the search for new candidates of anticancer drugs. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Dynamics of river–aquifer interactions along a chalk stream: the River Lambourn, UK
Authors: Grapes T. R. , Bradley C. , Petts G. E.
Published: March 2005

This paper describes the spatial and temporal pattern of groundwater flow accretion to the River Lambourn, a 234 km2 chalk catchment of the West Berkshire Downs, UK, which has been largely unaffected by groundwater abstraction. Variations in the discharge measured at four fixed gauges in the catchment, coupled with information on the length of flowing channel over the period 1983–2001, are used to describe regional patterns in flow accretion. Mean catchment accretion generally exceeds 0·15 m3 s−1 km−1, but there are significant differences between perennial reaches indicating how the combination of local structural controls and seasonal changes in the drainage net affect flow accretion. Data from current meter surveys were used to determine the spatial variability in flow accretion: 505 paired observations along 12 reaches between 1 and 2·95 km in length indicated a consistent spatial trend in accretion. Accretion was high in upstream and downstream channel reaches, and in middle reaches where dry valleys intersected the main valley. A flow accretion index was developed to describe the relationship of flow accretion in each of the 12 study reaches to catchment discharge. The relationship varied from a strong positive correlation with catchment discharge (two reaches), a weak positive correlation (three reaches), a strong negative correlation (two reaches), to no relationship to catchment discharge (four reaches). The results highlight the need to reconsider the usual assumption of uniform, or uniformly increasing, flow accretion in chalk catchments. Moreover, they emphasize the importance of catchment topography, and illustrate how flow accretion in individual reaches may vary between high and low groundwater levels. Copyright © 2005 John Wiley & Sons, Ltd.
Effect of biofiltration on particle characteristics and flocculation behavior
Authors: You Hueysong , Huang Chihpin , Cheng Hsinghsuong , Pan Jill Ruhsing
Published: March 2005

Biodegradable dissolved organic material and ammonia present problems for conventional water treatment processes and may contribute to biological instability in the treated water. One solution may be to use a biological process upstream of the regular water treatment process. Biofiltration may be cost‐effective in removing ammonia and the precursors of trihalomethanes but the characteristics of the biotreated effluent may affect to the subsequent coagulation process. A continuous flow biological filter packed with reticulated polyurethane foam markedly altered the particle size distribution and the charge density of the mixed liquor, shifting the granulometric distribution toward larger sizes. The mean and median diameter of the particles increased from 9.7 and 5.9 µm to 97.6 and 37.1 µm, respectively. The average charge density of the biofilter effluent (7.6 meq dm−3) was much lower than that of the raw water (12.7 meq dm−3). The optimum coagulant dosage for the subsequent coagulation was reduced substantially from 10 mg dm−3 to 1 mg dm−3 as Al due to the lowered charge density of the mixed liquor and the enhanced cation bridging of the extracellular polymers on the bioparticle surface. Copyright © 2005 Society of Chemical Industry
Reaction of sulfur mustard gas, soman and agent VX with nanosized anatase TiO2 and ferrihydrite
Authors: Štengl V , Maříková M , Bakardjieva S , Šubrt J , Opluštil F , Olšanská M
Published: March 2005

Homogeneous hydrolysis of titanium oxo‐sulfate and iron(III) sulfate has been used to prepare anatase TiO2 and ferrihydrite with high specific surface area. Resulting samples were characterised by specific surface area (Brunauer–Emmett–Teller method) and porosity (Barrett–Joyner–Halenda method) measurements, X‐ray powder diffraction (XRD) and scanning electron microscopy (SEM). The samples of anatase TiO2 and ferrihydrite were evaluated for their ability to degrade chemical warfare agents (sulfur mustard gas, soman and agent VX) to non‐toxic products. The largest percentage of mustard gas converted into non‐toxic products after the completion of the reaction was 99%. Copyright © 2005 Society of Chemical Industry
Temperature Sensitive Poly[N‐isopropylacrylamide‐co‐(acryloyl β‐cyclodextrin)] for Improved Drug Release
Authors: Zhang Jian‐Tao , Huang Shi‐Wen , Liu Ji , Zhuo Ren‐Xi
Published: March 2005

Summary: The model drugs ibuprofen (IBU) and tegafur (T‐Fu) were loaded into poly[N‐isopropylacrylamide‐co‐(acryloyl β‐cyclodextrin)] [P(NIPA‐co‐A‐CD)] and PNIPA hydrogels by immersing dried gels in IBU or T‐Fu alcohol solutions until they reached equilibrium. Drug release studies were carried out in water at 25 °C. In contrast to the release time of conventional PNIPA hydrogel, that of IBU from the β‐CD incorporated hydrogel was significantly prolonged and the drug loading was also greatly increased, which may be the result of the formation of inclusion complexes between CD and ibuprofen. However, another hydrophilic drug, tegafur, did not display these properties because it could not form a complex with the CD groups.

Cumulative release of IBU from P(NIPA‐co‐A‐CD) and PNIPA hydrogels as a function of time at 25 °C.

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Cumulative release of IBU from P(NIPA‐co‐A‐CD) and PNIPA hydrogels as a function of time at 25 °C.
Amphipathic and Membrane‐Destabilizing Properties of the Cationic Acrylate Polymer Eudragit® E100
Authors: Alasino Roxana V. , Ausar Salvador F. , Bianco Ismael D. , Castagna Leonardo F. , Contigiani Marta , Beltramo Dante M.
Published: March 2005

Summary:The cationic acrylate polymer Eudragit® E100 (E100) produces a biphasic effect on the stability of casein micelles disrupting their internal structure (S. F. Ausar et al.,J. Agric. Food Chem.2003,51, 4417). These results suggested that this polymer could have some amphipathic character. Therefore, in this study the polymer was characterized with respect to its interaction with different amphipathic systems (bile‐acid micelles, lipoproteins and liposomes), cell membranes (red blood cells) and virus membranes (Herpes simplex type 2 virus). As with caseins, a biphasic effect was observed with bile acids with a precipitation phase at low polymer/bile acid ratio and a solubilization phase when the polymer concentration was increased. Upon interaction with human plasma, an important reduction in cholesterol and triglycerides was observed upon remotion of E100 by a rise in pH to 8.5 and centrifugation. In agreement with this finding, an important reduction in plasma lipoproteins was observed upon its treatment with E100 and further remotion by pH rise and centrifugation. However, the amount of the major protein components of human plasma and the activity of several enzymes and antibodies were not affected by their treatment with E100. The membrane‐destabilizing properties of E100 were confirmed by its lytic activity on liposomes and red blood cells and by an important antiviral effect of E100 on Herpes simplex virus type 2. Altogether, these results show that, despite its water solubility and cationic character, E100 displays a significative amphipathic and membrane‐destabilizing character with potential biotechnological applications.

Native‐PAGE of human plasma lipoproteins after treatment with E100.

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Native‐PAGE of human plasma lipoproteins after treatment with E100.
Permeation and Separation Characteristics of a Mixture of Benzene/Cyclohexane through Cellulose Alkyl Ester Membranes during Pervaporation
Authors: Uragami Tadashi , Tsukamoto Kenji , Miyata Takashi
Published: March 2005

Summary: Cellulose alkyl esters such as ethyl, butyryl, pentyl, and heptyl cellulose with different numbers of carbon in the alkyl ester group were synthesized for the separation of a mixture of benzene/cyclohexane (Bz/Chx = 5/95 w/w) with a low concentration of benzene. All of cellulose alkyl ester membranes showed high benzene/cyclohexane selectivity for a Bz/Chx mixture in pervaporation. With increasing carbon number in the ester groups, the permeation rate increased but the benzene/cyclohexane selectivity decreased. The increase in the permeation rate could be attributed to an increase in the swelling of the membrane due to the feed mixture, and the decrease in the benzene/cyclohexane selectivity was dependent on both the decrease in the solubility selectivity and the diffusion selectivity. These pervaporation characteristics are discussed from the viewpoints of chemical and physical structure of the cellulose alkyl ester membranes such as the degree of swelling, the contact angle, and the density of the cellulose ester membranes, and the solution composition absorbed into their membranes.

Effects of the carbon number of alkyl group in the cellulose alkyl ester membranes on the benzene concentration in the permeate (•) and the permeation rate (○) for the mixture of benzene/cyclohexane during pervaporation.

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Effects of the carbon number of alkyl group in the cellulose alkyl ester membranes on the benzene concentration in the permeate (•) and the permeation rate (○) for the mixture of benzene/cyclohexane during pervaporation.
Micro‐Structured Electrode Arrays: Characterization of High Frequency Discharges at Atmospheric Pressure
Authors: Baars‐Hibbe Lutz , Sichler Philipp , Schrader Christian , Gericke Karl‐Heinz , Büttgenbach Stephanus
Published: March 2005

Summary: Micro‐structured electrode (MSE) arrays allow large area uniform glow discharges to be generated over a wide pressure range up to atmospheric pressure. Electrode widths, thicknesses and distances in the μm‐range are realized by means of modern micro machining and galvanic techniques. These electrode dimensions are small enough to generate sufficiently high electric field strengths to ignite gas discharges by applying only moderate radio frequency (RF, 13.56 MHz) voltages (80 V to 390 V in Ne, He, Ar, N2 and air). The non‐thermal plasma system can be characterized by a special probe measuring the electric parameters. MSE driven plasmas demonstrate different behavior from conventional RF or DC discharge plasmas. Due to the very small electrode gap width, d, the behavior of the charged particles in the RF field of our system could be described with the DC Townsend breakdown theory. Partially, dependent on the pressure range and type of gas, the breakdown mechanism was dominated by field electron emission or by a high frequency regime. The voltage‐current characteristic and electron density of the MSE plasma in He at atmospheric pressure were characteristic for a glow discharge. Using MSE arrays as plasma sources, several applications have been developed and successfully tested including atmospheric pressure plasma chemistry (decomposition of waste gases like CF4 and NO) and the sterilization of food packaging materials at atmospheric pressure.

Voltage‐current characteristic of a 100 kPa He RF glow discharge generated with an MSE array (d = 70 μm).

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Voltage‐current characteristic of a 100 kPa He RF glow discharge generated with an MSE array (d = 70 μm).
Binding of a highly potent protease‐activated receptor‐2 (PAR2) activating peptide, [3H]2‐furoyl‐LIGRL‐NH2, to human PAR2
Authors: Kanke Toru , Ishiwata Hiroyuki , Kabeya Mototsugu , Saka Masako , Doi Takeshi , Hattori Yukio , Kawabata Atsufumi , Plevin Robin
Published: March 2005

To determine the binding characteristics of a highly potent agonist for protease‐activated receptor‐2 (PAR2), 2‐furoyl‐Leu‐Ile‐Gly‐Arg‐Leu‐amide (2‐furoyl‐LIGRL‐NH2), whole‐cell binding assays were performed utilising a radioactive ligand, [3H]2‐furoyl‐LIGRL‐NH2.

Specific binding of [3H]2‐furoyl‐LIGRL‐NH2 was observed in NCTC2544 cells, dependent upon PAR2 expression, and competitively displaced by the addition of unlabeled PAR2 agonists. Scatchard analysis of specific saturation binding suggested a single binding site, with Kd of 122±26.1 nM and a corresponding Bmax of 180±6 f mol in 3.0 × 105 cells.

The relative binding affinities of a series of modified PAR2 agonist peptides obtained from competition studies paralleled their relative EC50 values for Ca2+ mobilisation assays, indicating improved binding affinities by substitution with 2‐furoyl at the N‐terminus serine.

Pretreatment of cells with trypsin reduced specific binding of [3H]2‐furoyl‐LIGRL‐NH2, demonstrating direct competition between the synthetic agonist peptide and the proteolytically revealed tethered ligand for the binding site of the receptor.

In HCT‐15 cells endogenously expressing PAR2, the binding of [3H]2‐furoyl‐LIGRL‐NH2 was displaced by addition of unlabeled ligands, Ser‐Leu‐Ile‐Gly‐Lys‐Val (SLIGKV‐OH) or 2‐furoyl‐LIGRL‐NH2. The relative binding affinity of 2‐furoyl‐LIGRL‐NH2 to SLIGKV‐OH was comparable to its relative EC50 value for Ca2+ mobilisation assays.

The binding assay was successfully performed in monolayers of PAR2 expressing NCTC2544 and human umbilical vein endothelial cells (HUVEC), in 96‐ and 24‐well plate formats, respectively.

These studies indicate that [3H]2‐furoyl‐LIGRL‐NH2 binds to human PAR2 at its ligand‐binding site. The use of this radioligand will be valuable for characterising chemicals that interact to PAR2.

British Journal of Pharmacology (2005) 145, 255–263. doi:10.1038/sj.bjp.0706189
Endothelin‐1 enhances oxidative stress, cell proliferation and reduces apoptosis in human umbilical vein endothelial cells: role of ETB receptor, NADPH oxidase and caveolin‐1
Authors: Dong Feng , Zhang Xiaochun , Wold Loren E , Ren Qun , Zhang Zhaojie , Ren Jun
Published: March 2005

Endothelin‐1 (ET‐1), an endothelium‐derived vasoactive peptide, participates in the regulation of endothelial function through mechanisms that are not fully elucidated. This study examined the impact of ET‐1 on oxidative stress, apoptosis and cell proliferation in human umbilical vein endothelial cells (HUVEC). HUVECs were challenged for 24 h with ET‐1 (10 pM–10 nM) in the absence or presence of the ETB receptor antagonist BQ788 (1 μM) or the NADPH oxidase inhibitor apocynin (1 μM). Reactive oxygen species (ROS) were detected using chloromethyl‐2′,7′‐dichlorodihydrofluorescein diacetate. Apoptosis was evaluated with 4′,6′‐diamidino‐2′‐phenylindoladihydrochloride staining and by the caspase‐3 assay. Cell proliferation was measured by a colorimetric assay. Expression of NADPH oxidase, Akt, pAkt, Bcl‐2, Bax, IκB, caveolin‐1 and eNOS was evaluated by Western blot analysis.

ET‐1 significantly enhanced ROS generation and cell proliferation following 24‐h incubation, both of which were prevented by BQ788 or apocynin, consistent with the ability of ET‐1 to directly upregulate NADPH oxidase. ET‐1 itself did not affect apoptosis but attenuated homocysteine‐induced apoptosis through an ETB receptor‐mediated mechanism. Western blot analysis indicated that ET‐1 alleviated homocysteine (Hcy)‐induced apoptosis, likely acting by antagonizing the Hcy‐induced decreases in Akt, pAkt, pAkt‐to‐Akt, Bcl‐2‐to‐Bax ratios and increases in Bax and caveolin‐1 expression. Furthermore, ET‐1 downregulated expression of caveolin‐1 and eNOS, which was attenuated by BQ788 or apocynin.

In summary, our results suggest that ET‐1 affects oxidative stress, proliferation and apoptosis possibly through ETB, NADPH oxidase, Akt, Bax and caveolin‐1‐mediated mechanisms.

British Journal of Pharmacology (2005) 145, 323–333. doi:10.1038/sj.bjp.0706193
Two distinct pathways account for EDHF‐dependent dilatation in the gracilis artery of dyslipidaemic hApoB+/+ mice
Authors: Krummen Stéphane , Falck John R , Thorin Eric
Published: March 2005

A universal endothelium‐derived hyperpolarising factor (EDHF – non‐NO/non‐PGI2) has not been identified. EDHF, however, is essential for the physiological control of resistance artery tone. The impact of dyslipidaemia (DL), a risk factor for cardiovascular diseases, on the nature and the efficacy of EDHF has not been evaluated yet.

Pressurised (80 mmHg) gracilis arterial segments isolated from mice expressing the human apoB‐100 and C57Bl/6 wild‐type (WT) mice were used. EDHF‐dependent dilatations to acetylcholine (ACh) were measured in the presence of L‐NNA (100 μM, NOS inhibitor) and indomethacin (10 μM, COX inhibitor).

Maximal EDHF‐induced dilatations were increased in DL when compared to WT (95±2 versus 86±4% in WT; P<0.05). Combination of apamin and charybdotoxin strongly reduced (P<0.05) ACh‐induced dilatation in WT (22±4%) and DL (25±5%).

Combined addition of barium (Ba2+) and ouabain abolished EDHF‐induced dilatations in WT arteries (13±3%; P<0.05). In vessels isolated from DL mice, however, only the addition of 14,15‐EEZE (a 14,15‐EET antagonist) to Ba2+ and ouabain prevented EDHF‐induced dilatations (5±3% compared to 54±11% in the presence of combined Ba2+ and ouabain; P<0.05).

Our data suggest that EDHF‐mediated dilatation depends on the opening of endothelial SKCa and IKCa channels. This is associated with the opening of Kir channels and activation of the Na+/K+‐ATPase pump on smooth muscle cells leading to dilatation. In arteries from DL mice, a cytochrome P450 metabolite likely to be 14,15‐EET equally contributes to the dilatory action of ACh. The early increased efficacy of EDHF in arteries isolated from DL mice may originate from the duplication of the EDHF pathways.

British Journal of Pharmacology (2005) 145, 264–270. doi:10.1038/sj.bjp.0706194
Italy as a negotiator in the EU equal opportunities policy process
Authors: Donà Alessia
Published: March 2005

The creation of both a Ministry and a Department for equal opportunities has been Italy's main institutional response to EU pressures in the field of equal opportunities policy. Nevertheless, the impact of Italian negotiators in the EU depends not only on the institutional resources available to them, but also on the political credibility acquired by presenting well-defined and clear preferences during the bargaining process in the Council. This article considers how the Italian position was presented, and how successful it was, in two recently approved Directives, one decided by qualified majority vote, the other on a basis of unanimity. The aim of the analysis is to assess Italy's capacity to influence EU social affairs. Information was gathered by conducting qualitative interviews with the main political actors involved in the decision-making process at the national and European levels.
Green currents for holomorphic automorphisms of compact Kähler manifolds
Authors: Dinh Tien-Cuong , Sibony Nessim
Published: March 2005

Letffbe a holomorphic automorphism of a compact Kähler manifold(X,ω)(X,\omega )of dimensionk≥2k\geq 2. We study the convex cones of positive closed(p,p)(p,p)-currentsTpT_p, which satisfy a functional relation\[f∗Tp=λTp,  λ>1,f^* T_p=\lambda T_p,\ \ \lambda >1,\]and some regularity condition (PB, PC). Under appropriate assumptions on dynamical degrees we introduce closed finite dimensional cones, not reduced to zero, of such currents. In particular, when the topological entropyh(f)\mathrm {h}(f)offfis positive, then for somem≥1m\geq 1, there is a positive closed(m,m)(m,m)-currentTmT_mwhich satisfies the relation\[f∗Tm=exp⁡(h(f))Tm.f^* T_m=\exp (\mathrm {h}(f)) T_m.\]Moreover, every quasi-p.s.h. function is integrable with respect to the trace measure ofTmT_m. When the dynamical degrees offfare all distinct, we construct an invariant measureμ\muas an intersection of closed currents. We show that this measure is mixing and gives no mass to pluripolar sets and to sets of small Hausdorff dimension.