bluuebunny/crossref_metadata_2025 huggingface dataset:
The Bee Fauna of Residential Gardens in a Suburb of New York City (Hymenoptera: Apoidea)
Authors: Fetridge Evelyn D , Ascher John S , Langellotto Gail A
Published: November 2008

As suburban landscapes expand, it is critical to understand their capacity to support wildlife. Pollinators, specifically bees (Hymenoptera: Apoidea: Anthophila), are to some degree compatible with urbanization and may be able to exist in suburbs in diverse assemblages. We surveyed 21 residential gardens for bees in Westchester County, a suburban area immediately north of New York City. From a sample of 1,675 individuals, we documented 110 species, of which 95% were native, 50% were solitary, and 93% were polylectic. In terms of abundance of specimens, eusocial (50% of specimens), native (97%), and polylectic (98%) bees were dominant. Contrary to our expectation, based on previous bee surveys in urban landscapes, the bee community documented was not depauperate in either soil-nesting or parasitic species (65 and 19% of species, respectively), nor was it enriched in exotic species (6% of species). Instead, the assemblage resembled the richer bee fauna documented at a 1,520-ha research preserve (forest) located in the same region, although certain specialist (oligolectic) and/or forest-associated species were absent. These results suggest that suburban landscapes in eastern North America have the potential to host relatively diverse and intact bee communities.
Distribution and Fine Structure of Antennal Sensilla in Emerald Ash Borer (Coleoptera: Buprestidae)
Authors: Crook D J , Kerr L M , Mastro V C
Published: November 2008

The antennal sensilla of the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), were examined using scanning and transmission electron microscopy. Male and female antennae have a scape, pedicel, and nine flagellomeres. Both male and female antennae share five sensillum types: sensilla chaetica (mechanoreceptors), three types of sensilla basiconica (olfactory), and uniporous gustatory/taste sensilla. Apical depressions containing large sensory fields of uniporous sensilla were seen on the eight most distal flagellomeres of both sexes. Counts of sensillum types showed that males possessed significantly more uniporous sensilla than females. We hypothesize that antennal contact is important for mate recognition by male A. planipennis. The distal apices of the eight outer flagellomeres were seen to have “tufts” composed of two types of sensilla basiconica. A third type of sensilla basiconica was observed within the perimeter of the uniporous sensory fields. The structure and putative function of each sensillum type are discussed.
Communication with Signals Produced by Abdominal Vibration, Tremulation, and Percussion inPodisus maculiventris(Heteroptera: Pentatomidae)
Authors: Žunič Alenka , Cokl Andrej , Doberlet Meta Virant , Millar Jocelyn G
Published: November 2008

Mating behaviors of the predaceous spined soldier bug, Podisus maculiventris (Say) (Pentatomidae: Asopinae), were observed, and vibrational signals used in intraspecific communication were recorded and analyzed. Only males produced vibrational signals, using three different vibrational modes: vibration of the abdomen, percussion with the front legs, or tremulation of the body. When recorded on a nonresonant substrate (a loudspeaker membrane), the mean dominant frequency of signals produced by abdominal vibration varied between 90 and 140 Hz, and of tremulatory signals between 8 and 22 Hz. Percussion signals were broad-band, with the dominant frequency ≈97 Hz and lower amplitude spectral peaks between 1,500 and 3,000 Hz. In the courtship phase of mating behavior, males emitted pulse trains composed of an abdominal vibration after a tremulatory pulse. Females stimulated by signals of abdominal vibration and composite signals expressed searching behavior and orientation toward the source of vibration, whereas no specific reaction to tremulatory signals was observed. Observations of mating behavior and playback experiments showed that the abdominal vibration signals had both long range calling and short range recognition functions. Tremulatory signals were emitted at close range and were essential for copulation to occur. The sequences of fast and repeated percussion signals were emitted both as individual signals during calling and courting or between vibratory and tremulatory pulses. However, unlike the other vibrational signals, percussion did not seem to be emitted in a particular behavioral context, and its possible function in eliciting responses from females is unclear.
Low‐complexity robust adaptive generalized sidelobe canceller detector for DS/CDMA systems
Authors: Elnashar Ayman , Elnoubi Said , Elmikati Hamdi
Published: November 2008

A novel low computational complexity robust adaptive blind multiuser detector, based on the minimum output energy (MOE) detector with multiple constraints and a quadratic inequality (QI) constraint is developed in this paper. Quadratic constraint has been a widespread approach to improve robustness against mismatch errors, uncertainties in estimating the data covariance matrix, and random perturbations in detector parameters. A diagonal loading technique is compulsory to achieve the quadratic constraint where the diagonal loading level is adjusted to satisfy the constrained value. Integrating the quadratic constraint into recursive algorithms seems to be a moot point since there is no closed‐form solution for the diagonal loading term. In this paper, the MOE detector of DS/CDMA system is implemented using a fast recursive steepest descent adaptive algorithm anchored in the generalized sidelobe canceller (GSC) structure with multiple constraints and a QI constraint on the adaptive portion of the GSC structure. The Lagrange multiplier method is exploited to solve the QI constraint. An optimal variable loading technique, which is capable of providing robustness against uncertainties and mismatch errors with low computational complexity is adopted. Simulations for several mismatch and random perturbations scenarios are conducted in a rich multipath environment with near–far effect to explore the robustness of the proposed detector. Copyright © 2008 John Wiley & Sons, Ltd.
Substrate determines asymmetrical gait dynamics in marmosets (Callithrix jacchus) and squirrel monkeys (Saimiri boliviensis)
Authors: Young Jesse W.
Published: November 2008

Studies of skeletal pathology indicate that injury from falling accounts for most long bone trauma in free‐ranging primates, suggesting that primates should be under strong selection to manifest morphological and behavioral mechanisms that increase stability on arboreal substrates. Although previous studies have identified several kinematic and kinetic features of primate symmetrical gaits that serve to increase arboreal stability, very little work has focused on the dynamics of primate asymmetrical gaits. Nevertheless, asymmetrical gaits typify the rapid locomotion of most primates, particularly in smaller bodied taxa. This study investigated asymmetrical gait dynamics in growing marmosets and squirrel monkeys moving on terrestrial and simulated arboreal supports (i.e., an elevated pole). Results showed that monkeys used several kinematic and kinetic adjustments to increase stability on the pole, including reducing peak vertical forces, limiting center of mass movements, increasing substrate contact durations, and using shorter and more frequent strides (thus limiting disruptive whole‐body aerial phases). Marmosets generally showed greater adjustment to pole locomotion than did squirrel monkeys, perhaps as a result of their reduced grasping abilities and retreat from the fine‐branch niche. Ontogenetic increases in body size had relatively little independent influence on asymmetrical gait dynamics during pole locomotion, despite biomechanical theory suggesting that arboreal instability is exacerbated as body size increases relative to substrate diameter. Overall, this study shows that 1) symmetrical gaits are not the only stable way to travel arboreally and 2) small‐bodied primates utilize specific kinematic and kinetic adjustments to increase stability when using asymmetrical gaits on arboreal substrates. Am J Phys Anthropol, 2009. © 2008 Wiley‐Liss, Inc.
Brief communication: Methods of sequence heterochrony for describing modular developmental changes in human evolution
Authors: Blomquist Gregory E.
Published: November 2008

Interest in the developmental changes leading to apomorphic features of human anatomy is longstanding. Although most research has focused on quantitative measures of size and shape, additional information may be available in the sequence of events in development, including aspects of phenotypic integration. I apply two recently proposed techniques for analyzing developmental sequences to literature data on human and chimpanzee age of limb element ossification center appearance in radiographs. The event‐pair cracking method of Jeffery et al. (Syst Biol 51 [2002] 478–491) offers little additional insight on sequence differences in this data set than a simpler difference of ranks. Both reveal shifts in timing that are likely related to locomotor differences between the two species. Poe's (Evolution 58 [2004] 1852–1855) test for modularity in a sequence identifies the ankle, wrist, and hind limb as developmental modules, which may correspond to localized combinations of developmental genes. Ossification patterns of the rays of the hand and foot show little modularity. Integrating these and other methods of sequence analysis with traditional metrics of size and shape remains an underdeveloped area of inquiry. Am J Phys Anthropol 2009. © 2008 Wiley‐Liss, Inc.
Platinum‐Containing Polyoxometalates
Authors: Cao Rui , Anderson Travis M. , Hillesheim Daniel A. , Kögerler Paul , Hardcastle Kenneth I. , Hill Craig L.
Published: November 2008

Späte Übergangsmetalle mit terminalen Oxoliganden: Zu dem von Lee, Kortz et al. beschriebenen Pt‐haltigen Polyoxovanadat [H2PtIVV9O28]5− werden kritische Anmerkungen, Analysen und Antworten vorgestellt. Außerdem wird abgeleitet, dass eine terminale Platin‐Sauerstoff‐Verbindung, die eine dieser Gruppen an anderer Stelle vorgestellt hat und die im Zusammenhang mit [H2PtIVV9O28]5− zitiert wurde, falsch zugeordnet wurde.
Platinum‐Containing Polyoxometalates
Authors: Kortz Ulrich , Lee Uk , Joo Hea‐Chung , Park Ki‐Min , Mal Sib Sankar , Dickman Michael H. , Jameson Geoffrey B.
Published: November 2008

Auf die Anmerkungen von Hill et al. zum platinhaltigen Polyoxovanadat [H2PtIVV9O28]5− antworten Kortz, Lee et al. Außerdem werden die Existenz des Anions α‐[SiW10PtIV2O40]8− und des Platin‐Oxo‐Komplexes [OPtIV(H2O)(PW9O34)2]16− diskutiert.
Platinum‐Containing Polyoxometalates
Authors: Cao Rui , Anderson Travis M. , Hillesheim Daniel A. , Kögerler Paul , Hardcastle Kenneth I. , Hill Craig L.
Published: November 2008

Late‐transition‐metal terminal oxo compounds: criticisms, analysis, and responses concerning the Pt‐containing polyoxovanadate [H2PtIVV9O28]5− reported by Lee, Kortz, and their co‐workers are presented. It is also deduced that a terminal platinum oxo compound from one of their groups, reported elsewhere but cited in connection with [H2PtIVV9O28]5−, is miss‐assigned.
Platinum‐Containing Polyoxometalates
Authors: Kortz Ulrich , Lee Uk , Joo Hea‐Chung , Park Ki‐Min , Mal Sib Sankar , Dickman Michael H. , Jameson Geoffrey B.
Published: November 2008

The comments of Hill and co‐workers regarding the platinum‐containing polyoxovanadate [H2PtIVV9O28]5− are responded to by Kortz, Lee and co‐workers. In addition, the existence of the anion α‐[SiW10PtIV2O40]8− and the platinum oxo complex [OPtIV(H2O)(PW9O34)2]16− are discussed.
Thermal, mechanical, and dielectric properties of polystyrene/expanded graphite nanocomposites
Authors: Goyal R. K. , Jagadale P. A. , Mulik U. P.
Published: November 2008

We herewith report the thermal, mechanical (modulus), and dielectric properties of polystyrene (PS)/expanded graphite (EG) nanocomposites fabricated by a simple technique of dispersing EG (up to 2.5 vol %) in PS matrix via solution method followed by hot pressing. The thermal stability and char yield of the nanocomposites are improved marginally. The modulus, electrical conductivity, dielectric constant, and dielectric loss tangent of the nanocomposites are significantly increased with EG content. The modulus of the nanocomposites increases by about twofold at 30°C compared with that of pure PS. The dielectric constant and the loss tangent of nanocomposites are increased up to 13‐fold and 200‐fold compared with that of pure PS, respectively, at 1 MHz and varied with frequency. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effect of thermal aging on the electrical properties of crosslinked polyethylene
Authors: Nedjar M.
Published: November 2008

This article reports on the effect of thermal aging on the electrical properties of crosslinked polyethylene (XLPE) used in high voltage cables. It was shown that thermal aging modifies the electrical properties of the polymer. The degradation is accelerated when the temperature is increased. This degradation is due to a thermooxidation, followed by a loss of antioxidant, and a change in color of the material. At 80 and 100°C, the antioxidant is practically efficacious during the aging, whereas at 120 and 140°C, it is consumed after 1500 and 1000 h, respectively, which results in an increase in the dielectric losses and a diminution in the volume resistivity. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and properties of a new green water‐soluble polymer for proton and metal‐cation sensing
Authors: Hu Yulin , Wang Baoyan , Su Zhixing
Published: November 2008

A novel water‐soluble colored polymer, based on 1,8‐naphthalimide, was synthesized through a series of easy reactions with high yields. It emitted green fluorescence both in an aqueous solution and in a solid state. Fluorescence characteristics of the polymer as a function of pH were investigated in aqueous solutions. The polymer solution showed weaker fluorescence in a more acidic medium. When the pH of the solution was higher than 5, stronger fluorescence could be seen with a pKa value of 3.5. The presence of metal cations (Mn2+, Fe3+, Co2+, Ni2+, Cu2+, and Zn2+) could quench the fluorescence intensity of an aqueous solution of this polymer to different levels. It was highly sensitive to Cu2+ and Fe3+ present in the studied system. The results suggest that this newly synthesized compound could work as a polymeric sensor responding to water polluted by Cu2+, Fe3+, and protons. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Controlling cellular morphology by supercritical carbon dioxide
Authors: Wang Dong , Jiang Wei , Gao Hong , Jiang Zhenhua
Published: November 2008

A series of high‐performance porous materials, including open‐cell and closed‐cell foams, were prepared by a two‐stage batch foaming process from fluorinated poly(arylene ether)s, and the porous morphology was characterized with scanning electron microscopy. The effects of saturation pressures, saturation temperatures, transfer times, molecular structures, and solvent traces on the cell sizes, cell densities, and bulk densities of porous materials were examined. According to the conclusions, the porous structures could be controlled with cellular sizes between the nanoscale and microscale. All nanoporous materials have dielectric constants in the ultralow‐dielectric‐constant range (1.4–2.0). The open structures can be prepared by two methods, and there are two kinds of morphologies from the two methods, including foams with small, spotlike openings (diameters between 10 and 100 nm) in the cell walls and bicontinuous nanoporous foams. Another special method for controlling the porous morphology was used here. Films with closed‐cell microcellular foams were placed in supercritical carbon dioxide again. The original morphology of the microcellular foam collapsed. The collapsed morphology was also characterized with scanning electron microscopy, and three kinds of cellular morphology were observed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Design of a Microstructured System for the Homogenization of Dairy Products at High Fat Content Part II: Influence of Process Parameters
Authors: Köhler K. , Aguilar F. A. , Schubert H. , Hensel A. , Schubert K. , Schuchmann H. P.
Published: November 2008

Partial homogenization using a microstructured SHM (Simultaneous Homogenizing and Mixing) valve significantly reduces aggregation of fat globules within their homogenization by feeding the continuous phase directly into the droplet disruption zone (as discussed in part I of this work). It allows homogenization of cream containing up to at least 42 vol.‐% fat, and thus, significantly reduces processing costs without loss in product quality, i.e., overall process intensification. The present article details current results on the influence of material parameters, i.e., emulsifier system and fat content, and process parameters, i.e., homogenizing pressure and the temperature of both streams, on the fat globule size distribution. In contrast to conventional technology, SHM valve technology generates decreasing droplet sizes with increasing pressure or with increasing temperature of the homogenizing stream. This novel technique breaks new ground in dairy product design.
An Adaptive Control Concept for Simulated Moving Bed Plants under Reduced Purity Requirements
Authors: Fütterer M.
Published: November 2008

Simulated moving bed (SMB) chromatography is an increasingly used separation technology. Several chromatographic columns are interconnected to form a ring. Cyclically, the feedings and drains are changed to allow a continuous separation. This process is very sensitive to parameter variation and disturbances. For this reason, an adaptive controller is suggested. The proposed controller is based on a simplified model and automatically adjusts the volumetric flow rates and switching time in order to achieve the desired purities. Simulation results are presented to give a first impression of the capabilities of this new control concept.
Structure Elucidation and Theoretical Investigation of Key Steps in the Biogenetic Pathway of Schisanartane Nortriterpenoids by Using DFT Methods
Authors: Xiao Wei‐Lie , Lei Chun , Ren Jie , Liao Tou‐Gen , Pu Jian‐Xin , Pittman Charles U. , Lu Yang , Zheng Yong‐Tang , Zhu Hua‐Jie , Sun Han‐Dong
Published: November 2008

Rubrifloradilactone C (4), a novel bioactive nortriterpenoid, along with four other nortriterpenoids (1–3, 5) were isolated from Schisandra rubriflora. The structure of 4 was determined by extensive NMR spectral analysis, computational evidence by using the GIAO method at the B3LYP/6–311++G(2d,p)//B3LYP/6–31G(d) levels, and X‐ray analysis. DFT at the B3LYP/6–311+G(d,p) level was selected to clarify the key mechanistic steps in the formation of 1 and 4 through transition‐state (TS) investigations. The effect of enzymes on the TS barriers was considered by using the polarized continuum model. Other possible products based on the new mechanism were predicted.
Use of toxicity assays for enantiomeric discrimination of pharmaceutical substances
Authors: De Andrés Fernando , Castañeda Gregorio , Ríos Ángel
Published: November 2008

Toxicity assays are commonly used as general indicators of environmental water pollution. In the study described here, selected toxicity tests have been used to evaluate the different toxicity levels of enantiomers of different pharmaceutical drugs that can be found as potential contaminants in water environments. Isomers of dopa, fluoxetine, and atenolol were tested with three aquatic organisms corresponding to different trophic levels: Daphnia magna (a crustacean), Pseudokirchneriella subcapitata (a microalga), and Tetrahymena thermophila (a protozoan). Different levels of toxicity were observed for each enantiomer, suggesting that significant enantioselectivity occurs in aquatic toxicity and that such enantiomeric differences must be considered when evaluating the ecological effects of these compounds. Chirality, 2009. © 2008 Wiley‐Liss, Inc.
Dreiphasige Butadien‐Telomerisationen im kontinuierlich betriebenen Schlaufenreaktor Teil 2: Bestimmung der Mikrokinetik
Authors: Behr A. , Dehn D.
Published: November 2008

Herkömmliche Reaktoren stoßen beim Einsatz der industriell etablierten Flüssig/Flüssig‐Zweiphasentechnik zum Recycling wertvoller Übergangsmetallkatalysatoren (Gas/Flüssig/Flüssig‐Reaktionen) an ihre Grenzen. Der erste Teil des vorliegenden Beitrags beschreibt homogenkatalysierte, dreiphasige Telomerisationen des Butadiens in einem neuartigen Schlaufenreaktor im kontinuierlichen Betrieb. Die dort vorgestellten Versuche dienen im vorliegenden zweiten Teil zusammen mit experimentell ermittelten makrokinetischen Daten und Modellgleichungen zum Phasenübergang zur Bestimmung der Mikrokinetik der dreiphasigen Telomerisationen. Mikrokinetische Daten sind für die technische Auslegung von industriellen Reaktoren von großer Bedeutung.
Steuerung der Lagerstabilität von Düngergranalien durch Additive?
Authors: Stelzer T. , Ulrich J.
Published: November 2008

Die Grundvoraussetzung eines jeden Düngers ist neben der Wirksamkeit die Lagerstabilität. Einflussfaktoren sind dabei z. B. die Morphologie oder die Festigkeit. Aus diesem Grund werden, wie z. B. in der Pharmazie auch, Additive zur Produktverbesserung eingesetzt. Bisher wurde in der Literatur nicht über die Möglichkeit diskutiert die Hydratationskinetik und die Wasseradsorption von granulierten Düngemitteln durch Additive zu beeinflussen. Die Lagerstabilität eines Produkts ist jedoch letztendlich von diesen beiden Faktoren maßgeblich beeinflusst. In der Arbeit wird für das Stoffsystem Harnstoff/Ammoniumsulfat und Aluminiumsulfathydrat als Additiv ein Weg aufgezeigt, die Lagerstabilität der Düngergranalien, durch die Beeinflussung des Aluminiumhydroxids im Dünger über die kontrollierbaren Prozessparameter wie chemische Zusammensetzung, Temperatur und Verweilzeit zu steuern.
An efficient pursuit automata approach for estimating stable all‐pairs shortest paths in stochastic network environments
Authors: Misra Sudip , Oommen B. John
Published: November 2008

This paper presents a new solution to the dynamic all‐pairs shortest‐path routing problem using a fast‐converging pursuit automata learning approach. The particular instance of the problem that we have investigated concerns finding the all‐pairs shortest paths in a stochastic graph, where there are continuous probabilistically based updates in edge‐weights. We present the details of the algorithm with an illustrative example. The algorithm can be used to find the all‐pairs shortest paths for the ‘statistical’ average graph, and the solution converges irrespective of whether there are new changes in edge‐weights or not. On the other hand, the existing popular algorithms will fail to exhibit such a behavior and would recalculate the affected all‐pairs shortest paths after each edge‐weight update.

There are two important contributions of the proposed algorithm. The first contribution is that not all the edges in a stochastic graph are probed and, even if they are, they are not all probed equally often. Indeed, the algorithm attempts to almost always probe only those edges that will be included in the final list involving all pairs of nodes in the graph, while probing the other edges minimally. This increases the performance of the proposed algorithm. The second contribution is designing a data structure, the elements of which represent the probability that a particular edge in the graph lies in the shortest path between a pair of nodes in the graph. All the algorithms were tested in environments where edge‐weights change stochastically, and where the graph topologies undergo multiple simultaneous edge‐weight updates. Its superiority in terms of the average number of processed nodes, scanned edges and the time per update operation, when compared with the existing algorithms, was experimentally established. Copyright © 2008 John Wiley & Sons, Ltd.
Measurement of Skin Perfusion Pressure in Hemodialyzed Patients: Association with Toe/Brachial Index
Authors: Shimazaki Masaru , Matsuki Takayuki , Yamauchi Kazuaki , Iwata Michihiro , Takahashi Hiroshi , Sakamoto Kenichi , Ohata Junichi , Nakamura Yuichi
Published: November 2008

BACKGROUND

Patients with diabetes mellitus or renal failure may have calcified lower leg arteries, causing a falsely raised ankle/brachial index (ABI). In such cases, other combined noninvasive complementary observations may be useful. The purpose of this study was to investigate vascular complications of lower extremities in chronic hemodialyzed patients by measuring skin perfusion pressure (SPP) and the toe/brachial index (TBI).

METHODS

Sixty‐five patients treated with regular hemodialysis were recruited. ABI, TBI, and SPP of the foot were measured in outpatient settings.

RESULTS

SPP was positively correlated with toe pressure (r = 0.560, p < 0.001) and with TBI (r = 0.481, p < 0.001). On the basis of the ABI results and diabetes status of the patients, 129 limbs were divided into 4 groups. For those in the normal ABI class (ABI >0.9), SPP and TBI were decreased in the diabetic normal ABI group compared with those in the non‐diabetic normal ABI group.

CONCLUSIONS

These findings not only support that diabetes is a risk factor for arteriosclerosis but also suggest that even in a normal ABI class, diabetic patients with end‐stage renal disease are already susceptible to arteriosclerotic assault of peripheral arterial complications. SPP measurement is a noninvasive, beneficial observation for lower extremity peripheral arterial disease in hemodialyzed patients at risk.
Feedback enlargement of stability radius by nondifferentiable optimization
Authors: Kawabata Keishi , Mori Takehiro
Published: November 2008

In controller design of dynamical systems, it is desirable that the controllers guarantee the stability for not only nominal plants but also perturbed ones, because the plant models may have some uncertainties in their parameters. By this motivation, several studies for the robust controller design have been conducted. In this paper, a feedback controller design method is considered, which achieves enlarging the degree of robust stability for the linear SISO closed‐loop systems. Choosing stability radius for the plant parameters as the degree of robust stability, and regarding this as an object function, we formulated this maximization as an optimization problem with constraints coming from prescribed pole placement. The difficulty of this formulation is that while pole placements give linear constraints, the object function is not a smooth one, which calls for an optimization technique for nondifferentiable functions. To cope with this, we successfully used the bundle method. We show some numerical examples to illustrate our proposed design method. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(3): 55–61, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20623
International comparison test in Asia‐Pacific region for impulse voltage measurements
Authors: Wakimoto Takayuki , Ishii Masaru , Goshima Hisashi , Hino Etsuhiro , Shimizu Hiroyuki , Li Yi , Ik‐Soo Kim
Published: November 2008

The national standard class divider for the lightning impulse voltage measurements in Japan was developed in 1998. After three years, the standard impulse voltage calibrator has also been manufactured. These standard equipment are used as an industrial standard, and the performance had been evaluated annually supported by the Ministry of Economy, Trade and Industry (METI). The standard impulse measuring system including the standard divider participated in the worldwide comparison test and its good performance was confirmed in 1999. Another international comparison test was carried out among three countries in the Asia‐Pacific region in 2004 again and the standard measuring system participated in the test. In this paper, the details and the results of the international comparison tests in 2004 are described. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(3): 46– 54, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20677
A numerical study on response modification, overstrength, and displacement amplification factors for steel plate shear wall systems
Authors: Kurban Can Ozan , Topkaya Cem
Published: November 2008

Design recommendations for steel plate shear wall (SPSW) systems have recently been introduced into seismic provisions for steel buildings. Response modification (R), overstrength (Ωo), and displacement amplification (Cd) factors for SPSW systems presented in design codes were based on professional experience and judgment. A numerical study has been undertaken to evaluate these factors for SPSW systems. Forty‐four unstiffened SPSW possessing different geometrical characteristics were designed based on the recommendations given in the AISC Seismic Provisions. Bay width, number of stories, story mass, and steel plate thickness were considered as the prime variables that influence the response. Twenty records were selected to include the variability in ground motion characteristics. In order to provide a detailed analysis of the post‐buckling response, three‐dimensional finite element analyses were conducted for the 44 structures subjected to the selected suite of earthquake records. For each structure and earthquake record, two analyses were conducted in which the first includes geometrical nonlinearities and the other includes both geometrical and material nonlinearities, resulting in a total of 1760 time history analyses. In this paper, the details of the design and analysis methodology are given. Based on the analysis results, response modification (R), overstrength (Ωo), and displacement amplification (Cd) factors for SPSW systems are evaluated. Copyright © 2008 John Wiley & Sons, Ltd.
Computation of incompressible flows with immersed bodies by a simple ghost cell method
Authors: Pan Dartzi , Shen Tzung‐Tza
Published: November 2008

The incompressible Navier–Stokes equations are solved by an implicit pressure correction method on Cartesian meshes with local refinement. A simple and stable ghost cell method is developed to treat the boundary condition for the immersed bodies in the flow field. Multigrid methods are developed for both velocity and pressure correction to enhance the stability and convergence of the solution process. It is shown that the spatial accuracy of the method is second order in L2 norm for both velocity and pressure. Various steady and unsteady flows over a 2D circular cylinder and a 3D sphere are computed to validate the present method. The capability of the present method to treat a moving body is also demonstrated. Copyright © 2008 John Wiley & Sons, Ltd.
Forecasting growth and inflation in an enlarged euro area
Authors: Flavin Thomas , Panopoulou Ekaterini , Pantelidis Theologos
Published: November 2008

We compare models for forecasting growth and inflation in the enlarged euro area. Forecasts are built from univariate autoregressive and single‐equation models. The analysis is undertaken for both individual countries and EU aggregate variables. Aggregate forecasts are constructed by both employing aggregate variables and by aggregating country‐specific forecasts. Using financial variables for country‐specific forecasts tends to add little to the predictive ability of a simple AR model. However, they do help to predict EU aggregates. Furthermore, forecasts from pooling individual country models usually outperform those of the aggregate itself, particularly for the EU25 grouping. This is particularly interesting from the perspective of the European Central Bank, who require forecasts of economic activity and inflation to formulate appropriate economic policy across the enlarged group. Copyright © 2008 John Wiley & Sons, Ltd.
Green tea drinking, high tea temperature and esophageal cancer in high‐ and low‐risk areas of Jiangsu Province, China: A population‐based case–control study
Authors: Wu Ming , Liu Ai‐Min , Kampman Ellen , Zhang Zuo‐Feng , van't Veer Pieter , Wu De‐Lin , Wang Pei‐Hua , Yang Jie , Qin Yu , Mu Li‐Na , Kok Frans J. , Zhao Jin‐Kou
Published: November 2008

Epidemiological studies suggested drinking green tea is inversely associated with esophageal cancer but results remain inconclusive. Moreover, inconsistent observations found high temperature drinks are associated with esophageal cancer. A population‐based case–control study was conducted in a high‐risk area (Dafeng) and a low‐risk area (Ganyu) of esophageal cancer in Jiangsu province China from 2003 to 2007. It aimed to explore green tea drinking and tea temperature with the risk of esophageal cancer, and to compare the difference between different risk regions. Using identical protocols, 1,520 cases and 3,879 healthy controls were recruited as study subjects in 2 regions. Detailed information was collected to assess green tea drinking habits. Unconditional logistic regression was used to obtain OR and 95% CI. Results showed that ever drinking green tea elevated OR in both counties (Dafeng OR = 1.2, 95% CI = 0.9–1.5; Ganyu: OR = 1.9, 95% CI = 1.4–2.4). Drinking tea at high temperature was found to increase cancer risk in both areas (Dafeng: OR = 1.9, 95% CI = 1.2–2.9; Ganyu OR = 3.1 95% CI = 2.2–4.3). However, after further adjustment for tea temperature, ever drinking tea was not related to cancer in either county (Dafeng: OR = 1.0, 95% CI = 0.7–1.3; Ganyu: OR = 1.3, 95% CI = 0.9–1.7). For dose‐response relationships, we observed positive relationship with monthly consumption of tea (p for trend = 0.067) and tea concentration (p for trend = 0.006) after further adjustment for tea temperature. In conclusion, green tea drinking was not inversely associated with esophageal cancer in this study. However, drinking tea at high temperatures significantly increased esophageal cancer risk. There was no obvious difference of green tea drinking between low‐ and high‐risk areas. © 2008 Wiley‐Liss, Inc.
Vitamin A deficiency injures liver parenchyma and alters the expression of hepatic extracellular matrix
Authors: Aguilar Rossana Pérez , Genta Susana , Oliveros Liliana , Anzulovich Ana , Giménez María Sofía , S. Sánchez Sara
Published: November 2008

Vitamin A is an essential lipid‐soluble nutrient that is crucial for morphogenesis and adult tissue maintenance. The retinoid homeostasis in the liver depends on a regular supply of vitamin A from an adequate dietary intake to preserve the normal organ structure and functions. This study focuses on the effect of vitamin A deficiency on the morphology and extracellular proteins expression of the liver in adult Wistar rats. Animals were fed with a normal (control group) or deficient vitamin A diet for 3 months. At the end of the experimental period, histological examination of the livers under light and electron microscopy revealed that vitamin A deficiency produced a loss of hepatocyte cord disposition with an irregular parenchymal organization. Abundant fat droplets were present in the cytoplasm of the hepatocytes. Elongated myofibroblastic‐like cells with an irregular cytoplasmic process and without lipid droplets could be seen at the perisinusoidal space, where an elevated intensity of alpha smooth muscle actin (α‐SMA) was observed. These results suggest that an activation of hepatic stellate cells (HSCs) occurred. Moreover, immunochemical methods revealed that vitamin A deficiency led to an increased expression of hepatic fibronectin, laminin and collagen type IV. We propose that vitamin A deprivation caused liver injury and that HSCs underwent a process of activation in which they produced α‐SMA and synthesized extracellular components. These changes may be a factor predisposing to liver fibrosis. In consequence, vitamin A deprivation could affect human and animal health. Copyright © 2008 John Wiley & Sons, Ltd.
Improved partition equilibrium model for predicting analyte response in electrospray ionization mass spectrometry
Authors: Du Lihong , White Robert L.
Published: November 2008

A previously proposed partition equilibrium model for quantitative prediction of analyte response in electrospray ionization mass spectrometry is modified to yield an improved linear relationship. Analyte mass spectrometer response is modeled by a competition mechanism between analyte and background electrolytes that is based on partition equilibrium considerations. The correlation between analyte response and solution composition is described by the linear model over a wide concentration range and the improved model is shown to be valid for a wide range of experimental conditions. The behavior of an analyte in a salt solution, which could not be explained by the original model, is correctly predicted. The ion suppression effects of 16 : 0 lysophosphatidylcholine (LPC) on analyte signals are attributed to a combination of competition for excess charge and reduction of total charge due to surface tension effects. In contrast to the complicated mathematical forms that comprise the original model, the simplified model described here can more easily be employed to predict analyte mass spectrometer responses for solutions containing multiple components. Copyright © 2008 John Wiley & Sons, Ltd.
Optimization of linear systems for 3D parallel simulation of semiconductor devices: Application to statistical studies
Authors: Seoane Natalia , García‐Loureiro Antonio , Aldegunde Manuel
Published: November 2008

The 3D simulators are nowadays essential in semiconductor device modelling in order to study fluctuation effects when devices are scaled to gate lengths approaching nanometre dimensions. To take into account these effects it is necessary to perform statistical studies, which have a high computational cost. The resolution of the linear systems generated by the discretization of partial differential equations is the most time‐consuming part of the simulation process. In this paper we propose an optimization of the linear system solution procedure based on domain decomposition methods implemented in a 3D parallel drift–diffusion device simulator. We have also carried out an analysis of the parallel performance of the device simulator. Numerical results show superlinear efficiency values up to 62 processors in the solution of the Poisson equation. The results were obtained on a Cluster HP Integrity Superdome. Copyright © 2008 John Wiley & Sons, Ltd.
Corrosion of type 316L stainless steel in molten LiCl–KCl salt
Authors: Shankar A. Ravi , Mudali U. Kamachi
Published: November 2008

Pyrochemical reprocessing in molten chloride salt medium has been considered as one of the best options for the reprocessing of spent metallic fuels. The AISI 316L stainless steel (SS) is envisaged as a candidate material for the fabrication of components for various unit operations like salt preparation vessel, electro‐refiner and cathode processor, on which ceramic coatings with metallic bond coat will be applied by the thermal plasma spraying. The unit operation like electro‐refining is carried out in the molten lithium chloride–potassium chloride (LiCl–KCl) eutectic salt at 773 K in argon atmosphere. The corrosion behaviour of the container vessel in molten chloride salts is therefore important, hence corrosion tests were carried out in a molten salt test assembly under argon gas atmosphere. The present paper discusses the corrosion behaviour of 316L SS in the molten LiCl–KCl eutectic salt at 873 K. The 316L SS samples were immersed in the molten LiCl–KCl eutectic for 25, 100 and 250 h, while 316L SS with yttria stabilized zirconia coating was exposed for 1000 h. The exposed samples were examined by optical and scanning electron microscope for corrosion attack. The X‐ray mappings of the cross‐section of the degraded layer onto the 316L SS indicated that the mechanism of corrosion corresponds to the selective diffusion of Cr to the surface with the formation of voids below, and the formation of chromium compounds at the surface. The results of the present study indicated that the yttria stabilized zirconia coating onto the 316L SS exhibits a better corrosion resistance in molten chloride salt than with uncoated 316L SS.
Highly‐Aligned Electrospun Luminescent Nanofibers Prepared from Polyfluorene/PMMA Blends: Fabrication, Morphology, Photophysical Properties and Sensory Applications
Authors: Kuo Chi‐Ching , Wang Cheng‐Ting , Chen Wen‐Chang
Published: November 2008

Highly‐aligned luminescent electrospun nanofibers were successfully prepared from two binary blends of PFO/PMMA and PF+/PMMA. The PFO/PMMA aligned electrospun fibers showed a core/shell structure but the PF+/PMMA fibers exhibited periodic aggregate domains in the fibers. The aligned fibers had polarized steady‐state luminescence with a polarized ratio as high as 4, much higher than the non‐woven electrospun fibers or spin‐coated film. Besides, the PF+/PMMA aligned electrospun fibers showed an enhanced sensitivity to plasmid DNA. Such aligned electrospun fibers could have potential applications in optoelectronic or sensory devices.

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γ‐Acyloxy‐ε‐Caprolactones: Synthesis, Ring‐Opening Polymerization vs. Rearrangement by Means of Chemical and Enzymatic Catalysis
Authors: Vaida Cristian , Takwa Mohamad , Martinelle Mats , Hult Karl , Keul Helmut , Möller Martin
Published: November 2008

Summary: γ‐Acyloxy‐ε‐caprolactones (3a–d) were prepared in two steps starting from 4‐hydroxy‐cyclohexanone (1). In the first step acylation of the hydroxyl group occurs and in the second step ring enlargement by Baeyer‐Villiger oxidation. If this order of reaction is inverted rearrangement occurs in the Baeyer‐Villiger oxidation of 4‐hydroxy‐cyclohexanone leading to γ‐hydroxyethyl‐γ‐butyrolactone. Using the first procedure γ‐acetyloxy‐ (3a), γ‐benzoyloxy‐ (3b), γ‐acryloyloxy‐ (3c), and γ‐ methacryloyloxy‐ε‐caprolactone (3d) were prepared. These monomers and for comparison reasons ε‐caprolactone and γ‐methyl‐ε‐caprolactone were polymerized by means of chemical and enzymatic catalysis. The results were different depending on the monomer structure and catalyst used. In the presence of a chemical catalyst, all the monomers, except γ‐acetyloxy‐ε‐caprolactone, undergo controlled ring‐opening polymerization. γ‐Acetyloxy‐ε‐caprolactone (3a), however, rearranges to a large extent under polymerization conditions to give γ‐acetyloxyethyl‐γ‐butyrolactone (6a). In the presence of an enzyme (Novozyme 435, Lipase B from Candida antarctica (CALB) immobilized on a macroporous resin) all γ‐acyloxy‐ε‐caprolactones partly rearrange to result the corresponding γ‐acyloxy‐γ‐butyrolactones, while ε‐caprolactone and γ‐methyl‐ε‐caprolactone yield the corresponding polymers, the latter even in a stereoselective manner as reported earlier in the literature. A molecular dynamic study was performed with 3a and 3b as substrates to gain information on the substrate recognition displayed by CALB. A mechanism for the chemically and enzymatically catalyzed reactions of γ‐acyloxy‐ε‐caprolactones is proposed.
Micro‐Encapsulation and Antifouling Coatings: Development of Poly(lactic acid) Microspheres Containing Bioactive Molecules
Authors: Faÿ Fabienne , Linossier Isabelle , Legendre Gaëlle , Vallée‐Réhel Karine
Published: November 2008

Summary: Environmental legislation compels marine paints companies to develop non toxic antifouling coatings respecting ecosystems. In this work, biodegradable polymers are used to conceive delivery systems with a lifetime of many months. For this purpose, chlorhexidine was encapsulated in poly(L‐lactide) microspheres and incorporated in antifouling formulations. The characterization (encapsulation yield, surface morphology, particle size) and antibacterial activity (bacteriostatic and bactericidal effects) of microspheres were carried out by using scanning electronic (SEM) and confocal laser scanning microscopies (CLSM). The results indicate a good ability of loaded microspheres to be formulated even though an excellent activity against selected marine bacteria is conserved. This is a promising approach to develop biodegradable antifouling paints based on non toxic molecules and bioactive surfaces.
Crystallinity and Crystalline Confinement of the Amorphous Phase in Polylactides
Authors: Sarasua Jose‐Ramon , Zuza Ester , Imaz Nagore , Meaurio Emilio
Published: November 2008

Summary: Stereorregular polylactides such as poly (L‐lactide) (PLLA) or poly (D‐lactide) result from polymerization of optically pure lactides and are semicrystalline. Optically non‐active poly(D,L‐lactide) (PDLLA) can be regarded as random or atactic copolymers, show a random moiety distribution, and are completely amorphous. In this work three phases, comprising mobile amorphous fraction (MAF, χMA), rigid amorphous fraction (RAF, χRA) and crystalline fraction (χc) were determined in PLLA. It will be shown that RAP fraction not only elevates Tg but also increases the dynamic fragility (m) of polylactide chains around the Tg. These results agree with reported cases in which topologycal constraints inhibit longer range dynamics and suggest a smaller length scale of cooperativity of chains in confined environments.
Keratin Coatings for Wool: Shrinkproofing and Nanoparticle Delivery
Authors: Cardamone Jeanette M. , Martin Justin J.
Published: November 2008

Summary: Wool fabrics were treated with keratin hydrolysate in isolated systems, in systems incorporating a cross‐linking enzyme, and in systems with nanoparticle silver. The dimensions of wool fabric were controlled after keratin applications and the strength of bleached wool fabric was improved. Keratin applications imparted these improved properties when applied alone and when applied with the enzyme. The enzyme was effective for in‐situ, solid‐state cross‐linking of wool fabric, cross‐linking keratin‐to‐keratin, and cross‐linking keratin‐to‐fabric. To further improve the properties of wool, nanoparticle silver was produced in various shapes. Transmission electron microscopy (TEM) micrographs of these particles showed discrete and isolated particles of size 8‐100 nm, dependent on the preparation. A combination of TEM and UV‐VIS spectroscopy was used to characterize these particles and scanning electron microscopy running in backscattered electron mode confirmed their placement on wool fibers. The application of nanoparticle silver to wool when co‐added with keratin may both improve dimensional stability and impart antimicrobial efficacy.
Octree‐based reasonable‐quality hexahedral mesh generation using a new set of refinement templates
Authors: Ito Yasushi , Shih Alan M. , Soni Bharat K.
Published: November 2008

An octree‐based mesh generation method is proposed to create reasonable‐quality, geometry‐adapted unstructured hexahedral meshes automatically from triangulated surface models without any sharp geometrical features. A new, easy‐to‐implement, easy‐to‐understand set of refinement templates is developed to perform local mesh refinement efficiently even for concave refinement domains without creating hanging nodes. A buffer layer is inserted on an octree core mesh to improve the mesh quality significantly. Laplacian‐like smoothing, angle‐based smoothing and local optimization‐based untangling methods are used with certain restrictions to further improve the mesh quality. Several examples are shown to demonstrate the capability of our hexahedral mesh generation method for complex geometries. Copyright © 2008 John Wiley & Sons, Ltd.