bluuebunny/crossref_metadata_2025 huggingface dataset:
Life-cycle costing of metallic structures
Authors: Gardner L. , Cruise R. B. , Sok C. P. , Krishnan K. , Ministro Dos Santos J.
Published: December 2007

Structural material selection has traditionally been based on initial material cost. However, growing pressure on the construction industry to consider the longer-term financial and environmental implications of projects is encouraging a more holistic view. Thus, materials with higher initial costs, but which offer cost savings over the life cycle of a structure, are gaining increasing recognition. The life-cycle costs of structures of two such metallic materials, namely aluminium alloy and stainless steel, are compared with those of ordinary structural carbon steel in the present study. Two structural applications—a typical office building and a bridge—are analysed, while offshore applications are briefly discussed. The ratio of initial material cost per tonne was assumed to be 1·0:2·5:4·0 (carbon steel:aluminium alloy:stainless steel). Following a preliminary structural design to current European design standards taking due account of the material densities and structural properties (principally strength and stiffness), it was found that on an initial cost basis, carbon steel offers the most competitive solution for both the building and the bridge. However, considering the additional life-cycle costs including maintenance costs, end-of-life costs and the residual value of the structure (appropriately discounted to present values), the results indicate that carbon steel offers the most competitive life-cycle solution for the office building but delivers the most expensive life-cycle solution for the bridge. Overall, it is concluded that on a whole-life basis aluminium alloy and stainless steel may offer more competitive solutions than carbon steel for bridges and exposed areas of building structures.
Constraining Aquifer Architecture with Electrical Resistivity Imaging in a Fractured Hydrogeological Setting
Authors: Rayner Scott F. , Bentley Laurence R. , Allen Diana M.
Published: December 2007

Two-dimensional and three-dimensional electrical resistivity imaging (ERI) surveys were conducted on the southern part of Saturna Island, British Columbia, and interpreted using a lithology- and structure-based hydrogeological conceptual model. Highly resistive sections of the images are interpreted as lightly fractured sandstone units of the Protection Formation. More conductive regions of the images are interpreted as the mudstones of the Cedar District Formation. The two-dimensional (2-D) cross sections contain sub-vertical zones of decreased resistivity that cut across the sub-horizontal formations. The three-dimensional (3-D) image displays a resistive formation on the western side of the image that is separated from a more conductive region by a sub-vertical contact. The sub-vertical contact in the 3-D image and the sub-vertical low resitivity zones in the 2-D images are aligned, and the low resistivity zones are interpreted as the intensely fractured Harris Fault zone. By interpreting the 2-D and 3-D ERI results using a hydrogeological conceptual model, and verifying the results against outcrop observations and previously-collected borehole video and geophysical data, the aquifer architecture can be accurately constrained at a sub-regional scale.
Effects of Education on Return-to-Work Status for People With Fear-Avoidance Beliefs and Acute Low Back Pain
Authors: Godges Joseph J , Anger Marie A , Zimmerman Grenith , Delitto Anthony
Published: December 2007

Background and Purpose

People with acute low back injury and fear-avoidance beliefs are at risk for remaining off work for an extended period of time. However, the effectiveness of intervention strategies for improving return-to-work status in people with acute low back pain and fear-avoidance beliefs has not been reported. The objective of this study was to determine whether education and counseling on pain management, physical activity, and exercise could significantly decrease the number of days that people with low back injury are off work.

Subjects

Thirty-four people who were unable to return to work following a work-related episode of low back pain and who exhibited fear-avoidance beliefs participated in this study.

Methods

Participants who scored 50 points or higher on the Fear-Avoidance Beliefs Questionnaire were alternately assigned to an education group or a comparison group. Both groups received conventional physical therapy intervention. Participants in the education group were given education and counseling on pain management tactics and the value of physical activity and exercise. The effectiveness of the interventions was measured by the number of days before people returned to work without restrictions.

Results

All participants in the education group returned to regular work duties within 45 days. One third of the participants in the comparison group remained off work at 45 days. There was a statistically significant difference between the groups with regard to the number of days before returning to work.

Discussion and Conclusion

Education and counseling regarding pain management, physical activity, and exercise can reduce the number of days off work in people with fear-avoidance beliefs and acute low back pain.
Estimation of Thigh Muscle Mass With Magnetic Resonance Imaging in Older Adults and People With Chronic Obstructive Pulmonary Disease
Authors: Mathur Sunita , Takai Karen PR , MacIntyre Donna L , Reid Darlene
Published: December 2007

Background and Purpose

Quantifying muscle mass is an essential part of physical therapy assessment, particularly in older adults and in people with chronic conditions associated with muscle atrophy. The purposes of this study were to examine the relationship between muscle cross-sectional area (CSA) and volume by use of magnetic resonance imaging (MRI) and to compare anthropometric estimations of midthigh CSA with measurements obtained from MRI.

Subjects and Methods

Twenty older adults who were healthy and 20 people with chronic obstructive pulmonary disease (COPD), matched for age, sex, and body mass index, underwent MRI to obtain measurements of thigh muscle CSA and volume. Anthropometric measurements (skinfold thickness and thigh circumference) were used to estimate midthigh CSA.

Results

Muscle volumes were significantly lower in the people with COPD than in the older adults who were healthy. Moderate to high correlations were found between midthigh CSA and volume in both groups (r=.61–.94). Anthropometric measurements tended to overestimate midthigh CSA in both the people with COPD (estimated CSA=64.9±17.8; actual CSA=48.3±10.2 cm2) and the older adults who were healthy (estimated quadriceps femoris muscle CSA=65.0±14.0; actual CSA=56.8±13.5 cm2). Furthermore, the estimated quadriceps femoris muscle CSAs were not sensitive enough to detect a difference in muscle size between people with COPD and controls. Thigh circumference alone was not different between groups and showed only low to moderate correlations with muscle volume (r=.19–.47).

Discussion and Conclusion

Muscle CSA measured from a single slice provides a good indication of volume, but the most representative slice should be chosen on the basis of the muscle group of interest. Thigh circumference is not correlated with muscle volume and, therefore, should not be used as an indicator of muscle size. The development of population-specific reference equations for estimating muscle CSA from anthropometric measurements is warranted.
Massage Therapy for Cancer Patients: A Reciprocal Relationship between Body and Mind
Authors: Sagar S.M. , Dryden T. , Wong R.K.
Published: December 2007

Some cancer patients use therapeutic massage to reduce symptoms, improve coping, and enhance quality of life. Although a meta-analysis concludes that massage can confer short-term benefits in terms of psychological wellbeing and reduction of some symptoms, additional validated randomized controlled studies are necessary to determine specific indications for various types of therapeutic massage. In addition, mechanistic studies need to be conducted to discriminate the relative contributions of the therapist and of the reciprocal relationship between body and mind in the subject. Nuclear magnetic resonance techniques can be used to capture dynamic in vivo responses to biomechanical signals induced by massage of myofascial tissue. The relationship of myofascial communication systems (called “meridians”) to activity in the subcortical central nervous system can be evaluated. Understanding this relationship has important implications for symptom control in cancer patients, because it opens up new research avenues that link self-reported pain with the subjective quality of suffering. The reciprocal body–mind relationship is an important target for manipulation therapies that can reduce suffering.
Radiofrequency Ablation and Cryoablation of Renal Tumours
Authors: Kwan K.G. , Matsumoto E.D.
Published: December 2007

With widespread utilization of noninvasive cross-sectional abdominal imaging [...]
Priority for Radium Therapy of Benign Conditions and Cancer
Authors: Mould R.F.
Published: December 2007

In medicine, assigning priorities for original ideas and for first implementation of a new type of treatment or technology—radium afterloading, for example—is often difficult. This situation is certainly true for radium therapy, with conflicting claims coming from France, Germany, and the United States about who first implemented it. Moreover, if possible, a distinction must be made between the person who had the idea for a therapy and the person who actually implemented it. These people are not always one and the same. Difficulties in assigning priority also sometimes arise from the lack of a published claim in a medical journal, and extant photographic evidence is typically almost impossible to find some 100 years after the event. The present article tries to solve the problems of priority regarding those who were really responsible for the ideas and implementation of radium therapy, including the technique of afterloading.
A heterogeneous acid‐catalyzed process for biodiesel production from enzyme hydrolyzed fatty acids
Authors: Su Chia‐Hung , Fu Chun‐Chong , Gomes James , Chu I‐Ming , Wu Wen‐Teng
Published: December 2007

In this work, biodiesel synthesis via fatty acids esterification with methanol is conducted by using a heterogeneous catalyst made from cation‐exchange resin. The kinetics of esterification is studied at the different levels of catalyst loading (3.65–53.6%, w/w), reaction temperature (333–353 K) and molar ratio of methanol to fatty acids (1:1 to 20:1). The reaction rate and fatty acids conversion increased with increases in catalyst loading, reaction temperature and molar ratio of feeding reactants. A pseudo‐homogeneous kinetic model coupling the effect of catalyst loading, reaction temperature and methanol/fatty acids molar ratio used for describing the process gave a correlation coefficient of 0.95 between experimental and predicted data. The proposed model was further used to predict the optimal operating condition for obtaining equilibrium conversion of 0.99. A reaction temperature of 372.15 K, molar ratio of feeding reactants of 14.9:1 and reaction time of 9.5 h was numerically calculated as the optimal operating condition. Under this optimal operating condition, an experimental verification was carried out and a satisfactory match was observed between experimental data and model prediction. © 2007 American Institute of Chemical Engineers AIChE J, 2008
Formation of carbon nanostructures and spatial‐energy stabilization criterion
Authors: Korablev G. A. , Zaikov G. E.
Published: December 2007

A spatial‐energy criterion of structure stabilization is obtained. The computational results for 100 binary systems correspond to the experimental data. The basic regularity of organic cyclic compound formation is given and its application for carbon nanostructures is shown. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Preparation and properties of nano‐CaCO3/acrylonitrile‐butadiene‐styrene composites
Authors: Wang Wen‐yi , Wang Guo‐quan , Zeng Xiao‐fei , Shao Lei , Chen Jian‐feng
Published: December 2007

CaCO3/acrylonitrile‐butadiene‐styrene (ABS) and CaCO3/ethylene‐vinyl acetate copolymer (EVA)/ABS nanocomposites were prepared by melting‐blend with a single‐screw extruder. Mechanical properties of the nanocomposites and the dispersion state of CaCO3 particles in ABS matrix were investigated. The results showed that in CaCO3/EVA/ABS nanocomposites, CaCO3 nanoparticles could increase flexural modulus of the composites and maintain or increase their impact strength for a certain nano‐CaCO3 loading range. The tensile strength of the nanocomposites, however, was appreciably decreased by adding CaCO3 nanoparticles. The microstructure of neat ABS, CaCO3/ABS nanocomposites, and CaCO3/EVA/ABS nanocomposites was observed by scanning electron microscopy. It can be found that CaCO3 nanoparticles were well‐dispersed in ABS matrix at nanoscale. The morphology of the fracture surfaces of the nanocomposites revealed that when CaCO3/EVA/ABS nanocomposites were exposed to external force, nano‐CaCO3 particles initiated and terminated crazing (silver streak), which can absorb more impact energy than neat ABS. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Development and validation of a method for the analysis of cafenstrole and its metabolite in brown rice grains and rice straw using high‐performance liquid chromatography
Authors: Abd El‐Aty A. M. , Lee Go‐Woon , Mamun M. I. R. , Choi Jeong‐Heui , Cho Soon‐Kil , Shin Ho‐Chul , Shim Jae‐Han
Published: December 2007

The present work reports the extraction and clean‐up procedures, as well as the chromatographic conditions developed, for the determination of cafenstrole and its metabolite (CHM‐03) residues in brown rice grains and rice straw using HPLC‐UV detection. The method makes use of an Apollo C18 column and acetonitrile : water : acetic acid as a mobile phase for both cafenstrole and its metabolite in rice and rice straw. Using these conditions cafenstrole and its metabolite were resolved with a retention time (Rt) of less than 14 min. The analytes were confirmed using positive atmospheric pressure ionization LC‐MS with selected ion monitoring. The average recoveries of cafenstrole were found to be 87.0–92.5 and 87.6–88.3%. However, they ranged from 81.5 to 81.6% and from 76.1 to 78.5% for cafenstrole metabolite (CHM‐03), in rice grains and rice straw, respectively, with relative standard deviations ranging from 1.4 to 6.6%. The limits of detection (LODs) of both cafenstrole and its metabolite were 0.002 and 0.02 ppm and 0.025 and 0.04 ppm, respectively. Field trials with recommended or double the recommended dose revealed that the herbicide could safely be recommended for application in rice and rice straw as no residues were detected in the harvest samples. Copyright © 2007 John Wiley & Sons, Ltd.
Selective and sensitive determination of bis(7)‐tacrine, a high erythrocyte binding acetylcholinesterase inhibitor, in rat plasma by high‐performance liquid chromatography–tandem mass spectrometry
Authors: Li Zhang , Hua Yu , Ming Li Wen , Chun Cheung Man , Ping Pang Yuan , Ge Lin , Tao Wang Yi , Zhong Zuo , Fan Han Yi
Published: December 2007

The current study aims to develop a specific and sensitive LC‐MS/MS method for determination of bis(7)‐tacrine (B7T) in rat plasma. A 100 µL plasma sample was extracted with ethyl acetate. B7T and the internal standard (IS), pimozide, in the samples were then analyzed with LC‐MS/MS in positive electrospray ionization condition. Chromatographic separation of B7T and IS was achieved in a C18 reversed‐phase HPLC column (150 × 2.1 mm i.d.) by isocratic elution with a mobile phase consisting of 0.05% formic acid in water and acetonitrile (1:1, v/v) at a flow rate of 0.35 mL/min. Multiple‐reaction monitoring (MRM) mode was employed to measure the ion transitions: m/z 247 to 197 for B7T and m/z 462 to m/z 328 for IS, respectively. The method was linear over the studied ranges of 100–5000 and 10–100 ng/mL. The intra‐day and inter‐day variations of the analysis were less than 6.8% with standard errors less than 9.0%. The detection limit of B7T in rat plasma was 1 ng/mL. The developed method was successfully applied to the pharmacokinetic study of B7T after intravenous administration of 1 mg/kg B7T and further proved to be readily utilized for determination of B7T in rat plasma samples. Copyright © 2007 John Wiley & Sons, Ltd.
Constructing the law: discourses and social practices
Authors: Tuffin Keith , Frewin Karen
Published: December 2007

This paper presents an analysis of everyday understandings of the law, within the context of a dispute between colonial and indigenous land interests in New Zealand. The analysis is informed by developments in the areas of critical legal studies, methodological critique of legal psychology, the social constructionist movement within social psychology, and the application of discursive psychology to understandings of racism. Data for this work was drawn from a corpus of letters to the editor of a newspaper, published in the city where the land dispute took place. Writers constructed the dispute as a legal issue and deployed two divergent constructions of the law. When the ‘primacy’ of the law was invoked, indigenous interests and the protesters were positioned as lawbreakers. When ‘the law in context’ was the resource used, protesters became positioned as seekers of justice. These variable constructions are discussed in terms of the social practices they engender and their wider contribution to debates regarding indigenous and colonial interests. Copyright © 2007 John Wiley & Sons, Ltd.
Gemischte Copolyamide mit verzweigten Diaminen
Authors: Schmidt‐Naake G. , Bode R.
Published: December 2007

Polyamide mit verzweigter Diaminkomponente sind amorphe Materialien mit den Eigenschaften thermoplastischer Elastomere. Glastemperaturen, mechanisches und rheologisches Verhalten sowie Modellrechnungen quantifizieren die Behinderung der Wasserstoffbrückenbindungen. Gemischte aliphatische Copolyamide mit verzweigten und unverzweigten Aminkomponenten sind Kunststoffe, die mit zunehmendem Verzweigungsgrad eine deutliche Modifizierung vom teilkristallinen Thermoplast zum amorphen, thermoplastischen Elastomer zeigen. Die thermischen und mechanischen Eigenschaften, Festigkeit, Elastizität und Transparenz des Materials lassen sich durch das Mischungsverhältnis der Komponenten steuern.
Verkürzte Zeolithsynthese unter Zugabe kleiner Feststoffperlen
Authors: Brehm A. , Zanter K.‐D.
Published: December 2007

Grundsätzlich lässt sich der Mechanismus der Zeolithnukleation im System flüssig/fest in verschiedene Teilbereiche einteilen: homogene bzw. heterogene (primäre) Nukleation, sekundäres Keimwachstum, Agglomerieren mehrerer Keime, begleitet von der Scherbeanspruchung innerhalb des Reaktors. Obwohl Prozesse wie die Scherbeanspruchung, die Agglomeration, das Zerbrechen oder der Abrieb eine Bewegung der Flüssigkeit benötigen, wurde bisher angenommen, dass ein Rühren während der Synthese die Kristallisation nicht entscheidend beeinflusst. In dieser Arbeit wurden ZSM‐5‐ und Na‐A‐Synthesen bei Atmosphärendruck im Reaktionskolben unter Zugabe von feinen Feststoffperlen spektroskopisch verfolgt. Die Rührwerkgeschwindigkeit wird dabei so eingestellt, dass alle Perlen aufgewirbelt werden (N > 300 rpm). Die Zugabe von suspendierten Feststoffperlen besitzt einen Einfluss auf den Kristallisationsprozess, so zerstören diese beispielsweise die lamellenförmigen, amorphen Partikel der Induktionsphase.
Zerstäuben von Suspensionen – Tropfengröße und ‐geschwindigkeit im Spray eines innenmischenden Zweistoffzerstäubers
Authors: Schmidt F. , Mewes D.
Published: December 2007

Für das Zerstäuben von Suspension wird ein Zweistoffzerstäuber mit innerer Mischung verwendet. Die dreiphasige Strömung im Zerstäuber besteht aus Wasser, Luft und Glaspartikeln. In Experimenten wird der Einfluss der volumetrischen Zusammensetzung der drei Phasen auf das erzeugte Spray untersucht. Die Bestimmung der Tropfengröße erfolgt mit Hilfe der Laser‐Beugungs‐Spektrometrie und die der Tropfengeschwindigkeit mittels Laser‐Doppler‐Anemometrie.
Charakterisierung der Geschwindigkeit und Blasengröße von Schäumen mit optischen Fasersensoren
Authors: Ji A. , Landwehr F. , Walzel P.
Published: December 2007

Schäume treten in vielen verfahrenstechnischen Prozessen bei mehrphasiger Betriebsweise auf. Sie sind teils unerwünscht, wie bspw. bei der Rektifikation oder Verdampfung, teils jedoch inhärenter Bestandteil des Verfahrens, wie z. B. bei der Flotation. Daneben werden Schäume auch als Formulierungsform eingesetzt, wie z. B. in der Feuerlösch‐, der Lebensmitteltechnik und in der Kosmetik [1, 2]. Die Eigenschaften von Schäumen, d. h., der Flüssigkeitsanteil, die durchschnittliche Blasengröße oder die Strömungsgeschwindigkeit sind oft nur schwer messbar [3]. Die in der vorliegenden Arbeit entwickelte Messtechnik auf der Basis von Lichtleitersensoren ist dafür gut geeignet. Die Schaumgeschwindigkeit und Blasengröße lassen sich durch Kreuzkorrelation der Signale aus zwei Lichtleiterfasern bestimmen, die versetzt in Strömungsrichtung angeordnet sind.
Poly(amido amine)s as Gene Delivery Vectors: Effects of Quaternary Nicotinamide Moieties in the Side Chains
Authors: Mateos‐Timoneda Miguel A. , Lok Martin C. , Hennink Wim E. , Feijen Jan , Engbersen Johan F. J.
Published: December 2007

To evaluate the effect of quaternary nicotinamide pendant groups on gene delivery properties, a series of poly(amido amine) (co)polymers were synthesized by Michael addition polymerization of N, N′‐cystaminebisacrylamide with variable ratios of 1‐(4‐aminobutyl)‐3‐carbamoylpyridinium (Nic‐BuNH2), and tert‐butyl‐4‐aminobutyl carbamate (BocNH‐BuNH2), yielding poly(amido amine)s (NicX‐NHBoc) with X=0, 10, 30, and 50 % of quaternary nicotinamide groups in the polymer side chains. Deprotection of the pendant Boc‐NH groups afforded an analogous series of polymers (NicX‐NH2) with higher charge density (due to the presence of protonated primary amino groups in the side chains) and subsequent acetylation yielded a series of polymers (NicX‐NHAc) of lower hydrophobicity than the Boc‐protected polymers. The polymers with the Boc‐protected or the acetylated amino groups showed high buffer capacity in the range pH 5.1–7.4, which is a property that can contribute to endosomal escape of polyplexes. The presence of quaternary nicotinamide groups has distinct beneficial effects on the gene vector properties of these polymers. The polymers containing ≥30 % of quaternary nicotinamide groups in their side chains condense DNA into small, nanosized particles (≤200 nm) with positive surface charge (≥+15 mV). Fluorescence experiments using ethidium bromide as a competitor showed that the quaternary nicotinamide groups intercalate with DNA, contributing to a more intimate polymer–DNA binding and shielding. Polyplexes of nicotinamide‐functionalized poly(amido amine)s NicX‐NHBoc and NicX‐NHAc, formed at 12/1 polymerDNA mass ratio, efficiently transfect COS‐7 cells with efficacies up to four times higher than that of PEI (Exgen 500), and with essentially absence of cytotoxicity. NicX‐NH2 polymers, possessing protonated primary amino groups in their side chains, have a higher cytotoxicity profile under these conditions, but at lower 3/1 polymer‐DNA mass ratio also these polymers are capable of efficient transfection, while retaining full cell viability.
Solution of the linear diffusion equation for modelling erosion processes with a time varying diffusion coefficient
Authors: Skianis Georgios Aim. , Vaiopoulos Dimitrios , Evelpidou Niki
Published: December 2007

In the present paper the differential equation of the temporal development of a landform (mountain) with a time dependent diffusion coefficient is solved. It is shown that the shape and dimensions of the landform at time t are independent of the specific variation of the diffusion coefficient with time; they only depend on the mean value of the diffusion coefficient in the time interval where the erosion process takes place. Studying the behaviour of the solution of the differential equation in the wave number domain, it is concluded that Fourier analysis may help in estimating, in quantitative terms, the initial dimensions, the age or, alternatively, the value of the diffusion coefficient of the landform. The theoretical predictions are tested on a hill of the southern part of the Ural mountainous region, in order to show how the results of the mathematical analysis can be used in describing, in quantitative terms, the morphological development of landforms due to erosion processes. Copyright © 2007 John Wiley & Sons, Ltd.
Adaptive interaction in a 3D product structure browsing system for maintenance training
Authors: Dong Wei , Li Zhizhong , Yan Jingbin , Wu Xingwei , Yang Yuhang , Zheng Li
Published: December 2007

The traditional maintenance training method with a physical model of the product is costly and inconvenient. Computer‐aided instruction (CAI) technology along with multimedia can provide much help in the training but provides limited interaction between the user and the system. In this article, a 3D model‐based product structure browsing system for maintenance training, CAMT, is developed for complex products adopting desktop virtual reality technology. To improve training performance, the interaction between the trainee and the CAMT system is enhanced by adaptive change of the zoom level, mouse sensitivity, and rotation origin. Details about the implementation of adaptive interaction are discussed. Experiments were conducted to test the effectiveness of this adaptive interaction. Seventy participants were arranged randomly into two groups assigned to perform product structure learning tasks using software with or without adaptive interaction functions. Statistical analysis showed that there were significant differences between the groups in task time, operation convenience, and learning satisfaction. Most participants preferred to use the system with adaptive interaction. It may be concluded that using adaptive interaction with maintenance training systems can significantly improve the usability of the systems and the efficiency of interactive learning. Although adaptive interaction has obvious advantages, our experiment also suggested that it is not a good idea to provide only the adaptive interaction mode. It is better to set adaptive interaction as the default mode but also to provide the possibility for a user to switch to a mode without adaptive interaction because a static view scope is also helpful to learn the 3D structure of a complex product. © 2007 Wiley Periodicals, Inc.
A novel approach to assessing percutaneous VX poisoning in the conscious guinea‐pig
Authors: Mumford Helen , Price Matthew E. , Wetherell Janet R.
Published: December 2007

Nerve agents like VX (S‐2‐diisopropylaminoethyl‐O‐ethyl‐methylphosphonothiolate) are potent irreversible acetylcholinesterase (AChE) inhibitors. Following percutaneous nerve agent exposure there is a slower rate of absorption, later onset and longer duration of signs of poisoning. Relatively little is known about the physiological effects of percutaneously applied nerve agent in unanaesthetised laboratory animals. Heart rate (ECG), brain electrical activity (EEG), body temperature, locomotor activity and clinical signs were monitored following percutaneous application of VX to conscious guinea‐pigs.

A fall in heart rate (bradycardia) preceded incapacitation following the highest VX dose, and occurred in the absence of incapacitation at the lower doses. Following the highest dose of VX (0.592 mg kg−1) three out of four animals died within 24 h. The lower two doses of VX (0.296 and 0.148 mg kg−1), produced extended periods of bradycardia in the absence of observable signs of poisoning. Bradycardia preceded, or occurred in the absence of, a temperature decrease; seizure‐like EEG changes were not observed at any of the VX doses tested. Acetylcholinesterase activity was significantly inhibited in the blood and most brain areas at 48 h. There were significant dose‐related decreases in body weight at 24 and 48 h following VX. This preliminary study suggests that decreased heart rate may be an early sign of the toxic effects of VX, whereas temperature and observable clinical signs are not good early indicators of percutaneous VX poisoning in this animal model. Future studies will use this model to assess the benefit of administering medical countermeasures in response to a defined decrease in heart rate. © Crown Copyright 2007. Reproduced with the permission of the Controller of HMSO. Published by John Wiley & Sons, Ltd.

This article was published online on 5 December 2007. An error was subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected [30 May 2008].
Calculation of the Segmental Order Parameter for a Polymer Chain in Good Solvent
Authors: Usatenko Zoryana , Sommer Jens‐Uwe
Published: December 2007

We have calculated the segmental tensor order parameter (second moment of orientation distribution function) of flexible polymer chains in a weak good solvent with fixed end‐to‐end distance and fixed segment length. Using the Edwards model for polymer chains with excluded volume interaction, we have performed direct perturbation expansions to obtain the two‐vector correlation function in one loop order. Our results indicate that distribution of tensor order parameter is not homogeneous along the chain as expected for ideal Gaussian statistics. Segmental order is lower as compared to Gaussian chains and decays toward the chain ends. These results are in agreement with computer simulation studies.

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Wellness promotion in the schools: Enhancing students' mental and physical health
Authors: Miller David N. , Gilman Rich , Martens Matthew P.
Published: December 2007

Wellness promotion addresses both the reduction of disorder and disease and the enhancement of mental and physical health. There is increasing evidence of a strong and reciprocal relationship between mental and physical health, and linking these two areas may be particularly useful for promoting positive youth development in school contexts. This article discusses the relationship between mental and physical health in children and adolescents, and how to promote both within schools. Topics discussed include the benefits of (a) hope and optimism, (b) structured extracurricular activities, and (c) sport and exercise psychology for school‐based health and wellness promotion. These topics are linked in that each has the potential to positively affect both mental and physical health in children and adolescents in schools. © 2007 Wiley Periodicals, Inc.
Pure white‐light‐emitting diodes from phosphorescent single polymer systems
Authors: Lee Po‐I , Hsu Steve Lien‐Chung , Lee Jung‐Feng
Published: December 2007

New white polymeric light‐emitting diodes from phosphorescent single polymer systems have been developed using a blue‐light‐emitting fluorene monomer copolymerized with a red‐light‐emitting phosphorescent dye, and end‐capped with a green‐light‐emission dye. All of the copolymers have good thermal stability with 5% weight loss temperatures at 380–413 °C and glass transition temperatures at 75–137 °C. We obtained white‐light‐emission devices by adjusting the molar ratio of the comonomers with a structure of indium tin oxide/poly(3,4‐ethylenedioxythiophene): poly(styrene sulfonic acid)/polyvinylcarbazole (PVK)/emission layer/Ca/Ag. The highest brightness in such a device configuration is 300 cd/m2 at a current density of 2900 A/m2 with high white color quality (Commission Internationale de l'Eclairage (CIE) coordinates of (0.33, 0.34)). © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 464–472, 2008
Cationic ring‐opening copolymerization behavior of trioxane and seven‐membered cyclic carbonate
Authors: Nagai Daisuke , Yokota Kensuke , Ogawa Takuma , Ochiai Bungo , Endo Takeshi
Published: December 2007

Cationic ring‐opening copolymerization behavior of trioxane (TOX) and a seven‐membered cyclic carbonate, 1,3‐dioxepan‐2‐one (7CC) is described. When TOX and 7CC were cationically copolymerized under various feed ratios using trifluoromethane sulfonic acid (TfOH) as an initiator in nitrobenzene at 30 °C, 7CC was consumed faster than TOX and the decarboxylation was accompanied to afford the corresponding polyacetal–polycarbonate type copolymers containing poly(oxytetramethylene) units. The copolymer composition could be controlled by the feed ratio of 7CC, whose increase resulted in the high copolymer composition of the 7CC unit. The solubility of the copolymers increased as the increase of the 7CC content. Thermogravimetric, size‐exclusion chromatographic, and X‐ray analyses of the copolymers suggest that the sequences of the copolymer chains consist of the segments containing the units originated from 7CC and those with TOX unit‐rich compositions. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 733–739, 2008
Influence of preparation methods on the structures and properties for the blends between polyamide 6co6T and polyamide 6: Melt‐mixing and in‐situ blending
Authors: Wang Xiaochun , Zheng Qiang , Du Libo , Yang Guisheng
Published: December 2007

Two blends between polyamide 6 (PA6) and Polyamide 6co6T (PA6co6T, a random copolymer between polyamide 6 and polyamide 6T) were fabricated by melt‐mixing on a twin‐screw extruder and the subsequent injection molding, or through the in‐situ polymerization of ε‐caprolactam in the presence of PA6co6T. As far as the former method is concerned, there exist an obvious decline of toughness and a slight increase in strength and modulus; however, for the latter, there appear a remarkable improvement in toughness and a simultaneous moderate increase in strength and modulus. A series of characterizations were carried out including scanning electron microscopy, wide‐angle X‐ray diffraction, polarized optical microscopy, differential scanning calorimetry, dynamic mechanical analysis, and Fourier transform infrared spectrometry. It is found that both blends exhibit single glass transition on DMA tan δ curves. However, contrary to that of the melt‐mixed blends, the glass transition temperature (Tg) of the in‐situ ones decreases with increasing PA6co6T content. It is suggested that different mixing levels are the main reasons. Moreover, the addition of PA6co6T containing linear rigid segments conducts remarkable refinement of spherulites for the blends. Significantly different changes in the crystallographic form, spherulite size, crystalline content and perfection due to the introduction of PA6co6T for the two blends are ascribed to their varied thermomechanical histories and the presence of interchange reaction only for the in‐situ blends. On the basis of the characterizations of the microstructures, the different trends of changes in the mechanical properties with the addition of PA6co6T for the two fabrication methods are discussed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 201–211, 2008
Prozesssichere Vakuumerzeugung bei feststoffbelasteten Saugmedien
Authors: Hähre Pierre
Published: December 2007

Die Erzeugung von Vakuum bei gleichzeitig hoher Feststoffverträglichkeit der Vakuumpumpen stellt in vielen Bereichen der Prozessindustrie eine Herausforderung dar. Konventionelle Denkmuster führen zu Lösungen, welche Filtrationen im Vakuum notwendig machen — ein oft fataler Ansatz und Kostentreiber.

In diesem Artikel wird am Beispiel der Extruderentgasung dargestellt, welcher Aufwand hinsichtlich Abscheidung und Wäsche getrieben wird, obwohl die kostengünstige Lösung doch so nah ist. Eine Marktrecherche oder ein Gespräch mit vorhandenen und potentiellen Zulieferern offenbart nicht selten sehr einfache Lösungsansätze.
Epac signaling pathway involves STEF, a guanine nucleotide exchange factor for Rac, to regulate APP processing
Authors: Zaldua Natalia , Gastineau Monique , Hoshino Mikio , Lezoualc'h Frank , Zugaza José L.
Published: December 2007

The amyloid precursor protein (APP) is a key protein involved in the development of Alzheimer's disease. We previously identified a signal transduction secretory pathway in which the small G protein Rac sets downstream of the cAMP/Epac/Rap1 signalling cascade regulating the α cleavage of APP [Maillet, M. et al. (2003) Crosstalk between Rap and Rac regulates secretion of sAPPα. Nat. Cell Biol. 5, 633–639]. We now report that Rap1 can physically and specifically associate with the guanine nucleotide exchange factor (GEF) STEF through its TSS region. A deleted TSS domain of STEF cells fails to activate Rac1 and dramatically decreases secretion of the non‐amyloidogenic soluble form of APP (sAPPα) induced by the cAMP‐binding protein Epac. Altogether, our data show that upon Epac activation, Rap1 recruits STEF through its TSS region and activates Rac1, which mediates APP processing.
A NOTE ON THE OPTIMAL LEVEL OF MONETARY AGGREGATION IN THE UNITED KINGDOM
Authors: ELGER C. THOMAS , JONES BARRY E. , EDGERTON DAVID L. , BINNER JANE M.
Published: December 2007

Weak separability is a key admissibility property in the Divisia approach to monetary aggregation. We test groups of U.K. household sector monetary assets for weak separability using new data underlying the Bank of England's benchmark revision of its household sector Divisia index. Nonparametric tests are used to identify four monetary asset groupings, which are weakly separable over all or almost all of the post-ERM period (1992:4–2005:1). We construct Divisia monetary aggregates for these four groupings and investigate their information content in two applications. The main findings are that Divisia money has direct effects on aggregate demand and that the growth rates of the nominal Divisia monetary aggregates Granger cause nominal output growth, but not inflation.
The link between post-qualification experience and self-confidence ratings in two problem-solving domains: a study of radiation therapists
Authors: Ferris Helena , McKenzie Kenneth , Thomas Kevin , Craig Agnella
Published: December 2007

Recognising one’s abilities and limits in clinical tasks is a valuable part of professionalism. This study investigated the self-ratings of problem-solving confidence of radiation therapists (RTs) in two domains: clinical scenarios and critical thinking items (CTIs). We divided the 60 participants into three groups based on post-qualification experience (PQE), and found that greater PQE was linked with higher self-rated confidence for clinical scenarios, but not for CTIs.
Repeating earthquake finite source models: Strong asperities revealed on the San Andreas Fault
Authors: Dreger Douglas , Nadeau Robert M. , Chung Angela
Published: December 2007

We investigate the rupture process of a sequence of repeating Mw 2.1 earthquakes on the San Andreas Fault in Parkfield spanning the occurrence of the September 28, 2004 mainshock by inverting seismic moment rate functions obtained from empirical Green's function deconvolution. The results show that these events have extremely concentrated slip patches with radii on the order of 10–20 m, with peak slip between 8.4 and 11.4 cm. The rupture speed and rise time are consistent with values of larger earthquakes. The spatial distribution of stress drop for the events shows low average values 2.5–5.6 MPa and very large peak values of 66.7–93.9 MPa. The results show that strong asperities can exist at small scales on an otherwise weak fault, and helps reconcile differences between traditional spectra‐based and tectonic loading methods for determining the stress drop of small repeating earthquakes.
Evaluation of plasticity driven material damage using Lamb waves
Authors: Pruell Christoph , Kim Jin-Yeon , Qu Jianmin , Jacobs Laurence J.
Published: December 2007

This letter reports on the experimental observation of a direct correlation between the acoustic nonlinearity measured with Lamb waves and the level of plasticity in a metal specimen. This correlation implies that even though Lamb waves are multimodal and dispersive, they will interact with a material’s plasticity in a manner similar to longitudinal and Rayleigh waves; there is a fundamental relationship between material plasticity and acoustic nonlinearity that is independent of wave type. As a result, Lamb waves can be used to quantitatively assess plasticity driven material damage using established higher harmonic generation techniques.
Kinetic theory of radial angular momentum flux of collisional plasmas in an axisymmetric magnetic field
Authors: Wong S. K. , Chan V. S.
Published: December 2007

A recent calculation [P. J. Catto and A. N. Simakov, Phys. Plasmas 12, 012501 (2005)] of the radial angular momentum flux for collisional plasmas with small toroidal flows using fluid equations is at variance with an existing result [R. D. Hazeltine, Phys. Fluids 17, 961 (1974)] based on a drift kinetic approach. The difference has been ascribed to the incompleteness of the drift kinetic equation when second order accuracy in the ratio of gyroradius over scale length is required. This paper reformulates the problem starting from the full kinetic equation that includes gyromotion and performs an expansion in the same ratio. The drift kinetic equation being used is recovered by keeping leading order terms in an additional expansion of poloidal to toroidal magnetic fields. Solving the equation in the Pfirsch–Schlüter regime leads to an agreement with the fluid approach, after correcting an error in the existing drift kinetic calculation.
Characteristics of geodesic acoustic mode zonal flow and ambient turbulence at the edge of the HL-2A tokamak plasmas
Authors: Zhao K. J. , Dong J. Q. , Yan L. W. , Hong W. Y. , Lan T. , Liu A. D. , Qian J. , Cheng J. , Yu D. L. , Huang Y. , He H. D. , Liu Yi. , Yang Q. W. , Duan X. R. , Song X. M. , Ding X. T. , Liu Y.
Published: December 2007

The three-dimensional characteristics of the geodesic acoustic mode zonal flows (GAMZFs) and the ambient turbulence (AT) at the edge of the HuanLiuqi-2A tokamak [Y. Liu et al., Nucl. Fusion 45, S203 (2005)] are investigated with Langmuir probe arrays and the results are presented in detail. The toroidal and poloidal symmetries, and the radial scale of the GAMZFs are simultaneously identified. The envelopes of the high frequency components of the AT in the presence of the GAMZFs are analyzed. The GAM frequency components (GAMFCs) of the coherent envelopes are also shown to have poloidal and toroidal symmetries, and similar radial scales as the GAMZF does. The correlation between the GAMFCs of the envelopes and the GAMs is high, with phase shifts between π/2 to π, indicating that the GAMZFs may regulate the AT and the regulation is embodied in the envelopes. Three-wave coupling between GAM and AT is found to be a plausible formation mechanism for the former, which acts on the whole spectra of the latter within its scale length. The temporal evolutions of the total fluctuation power, the GAM and the AT powers show that the AT power decreases when GAM power increases and vice versa, indicating possible regulating effects of the latter on the former.
Modified substrate-current model for high voltage n-channel metal-oxide-semiconductor transistor and its implication on transistor design
Authors: Dai Mingzhi , Yap A. , Huang K. , Huang S. Y. , Wang J. , Wang S. , Jiang I. , Zhang W. J. , Yi L. , Cheng A. , Liu S. H. , Liao K. Y.
Published: December 2007

A simple analytical model with two high-electric-field regions, instead of only one shifted high-electric-field region (the Kirk effect), is proposed to explain the unusual substrate-current behavior in very short high voltage n-channel metal-oxide-semiconductor transistors. This model agrees well with the experimental data in terms of the substrate-current dependence on VGS, VDS, process, and structures.
Emission enhancement behaviors in the coupling between surface plasmon polariton on a one-dimensional metallic grating and a light emitter
Authors: Wang Jyh-Yang , Kiang Yean-Woei , Yang C. C.
Published: December 2007

The authors study numerically the enhancements of dipole radiation rate and emission efficiency in a structure of a sinusoidal interface between a half space of metal and a half space of dielectric. The surface plasmon polaritons (SPPs) generated at the interface couple with the dipole to enhance its radiation rate. The energy dependence of radiation rate relies on the factors of SPP density of state, dipole position, and the emission efficiency. Below the light line, the emission efficiency is controlled by the localized surface plasmon (SP) field distribution in coupling two counterpropagating SPP modes near the Brillouin zone boundary. A localized SP field distribution of higher intensity and higher emission efficiency leads to a higher dipole radiation rate and a higher emission fraction.
Wide-view transflective liquid crystal display for mobile applications
Authors: Kim Hyang Yul , Ge Zhibing , Wu Shin-Tson , Lee Seung Hee
Published: December 2007

A high optical efficiency and wide-view transflective liquid crystal display based on fringe-field switching structure is proposed. The transmissive part has a homogenous liquid crystal (LC) alignment and is driven by a fringe electric field, which exhibits excellent electro-optic characteristics. The reflective part has a hybrid LC alignment with quarter-wave phase retardation and is also driven by a fringe electric field. Consequently, the transmissive and reflective parts have similar gamma curves.
Enhanced photoresponse in ZnO nanowires decorated with CdTe quantum dot
Authors: Aga R. S. , Jowhar D. , Ueda A. , Pan Z. , Collins W. E. , Mu R. , Singer K. D. , Shen J.
Published: December 2007

The photoresponse of ZnO nanowires irradiated with photons having energies below the band gap of ZnO (3.4eV) was studied before and after deposition of CdTe quantum dots via a pulsed electron-beam technique. The small amount of deposited CdTe did not increase the dark current of the samples. However, a substantial increase in the steady state photocurrent was observed after CdTe deposition suggesting a clear photosensitization effect. Results revealed that CdTe influences the photoconductivity transients of ZnO by minimizing its interaction with oxygen in air as well as providing additional traps that serve to increase the photocurrent time constant.
RET signaling does not modulate MPTP toxicity but is required for regeneration of dopaminergic axon terminals
Authors: Kowsky Sebastian , Pöppelmeyer Charlotte , Kramer Edgar R. , Falkenburger Björn H. , Kruse Anja , Klein Rüdiger , Schulz Jörg B.
Published: December 2007

Activation of the RET (rearranged during transfection) receptor by glial cell-line-derived neurotrophic factor (GDNF) has been identified as an important differentiation and survival factor for dopaminergic neurons of the midbrain in preclinical experiments. These encouraging results have led to clinical trials of GDNF in patients with Parkinson's disease, which have resulted in conflicting findings. To investigate the potential benefit of Ret-dependent signaling on the challenged dopaminergic system, we tested the effect of tissue-selective ablation of the
Ret
gene on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxicity in mice, the most widely used animal model for Parkinson's disease. Ablation of
Ret
did not modify the MPTP-induced loss of dopaminergic neurons in the substantia nigra pars compacta and the dopaminergic innervation of the striatum at 14 days. However,
Ret
ablation abolished the regeneration of dopaminergic fibers and terminals, as well as the partial recovery of striatal dopamine concentrations, that was observed in control mice between days 14 and 90 after MPTP treatment. We therefore conclude that RET signaling has no influence on the survival of dopaminergic neurons in the MPTP model of Parkinson's disease but rather facilitates the regeneration of dopaminergic axon terminals.