bluuebunny/crossref_metadata_2025 huggingface dataset:
Learning in different modes: the interaction between incremental and radical change
Authors: Petersen Anders H. , Boer Harry , Gertsen Frank
Published: December 2004

The objective of the study presented in this article is to contribute to the development of theory on continuous innovation, i.e. the combination of operationally effective exploitation and strategically flexible exploration. A longitudinal case study is presented of the interaction between incremental and radical change in Danish company, observed through the lens of organizational learning. The radical change process is described in five phases, each of which had its own effects on incremental change initiatives in the company. The research identified four factors explaining these effects, all of which are related to the timely availability of key competencies. Copyright © 2004 John Wiley & Sons, Ltd.
A hybrid formulation of eddy current problems
Authors: Rodríguez Ana Alonso , Hiptmair Ralf , Valli Alberto
Published: December 2004

In this article we examine the well‐known magneto‐quasistatic eddy current model for the behavior of low‐frequency electromagnetic fields. We restrict ourselves to formulations in the frequency domain and linear materials, but admit rather general topological arrangements. The generic eddy current model allows two dual formulations, which may be dubbed E‐based and H‐based. We investigate the so‐called hybrid approach that combines both formulations by means of coupling conditions across the boundaries of conducting regions. The resulting continuous and discrete variational formulations will be discussed, and an optimal error estimate for edge finite elements will be proved. It is worthy to note that for this approach no difficulties arise from the topology of the conducting regions. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2005
White spirit permeation resistance of polyethylene, polyethylene/modified polyamide, and polyethylene/blends of modified polyamide and ethylene vinyl alcohol bottles
Authors: Yeh Jen‐Taut , Huang Shyh‐Shiuan , Chen Heng‐Yi
Published: December 2004

The main objective of this study was to investigate the barrier properties of polyethylene (PE), PE/modified polyamide (MPA), and PE/blends of modified polyamide and ethylene vinyl alcohol (MPAEVOH) bottles against white spirit permeation. After MPAEVOH barrier resins were blended with PE, the resistance of the PE/MPAEVOH bottles against white spirit permeation was significantly improved compared to the PE bottle. Surprisingly, with proper compositions of MPAEVOH resins, the white spirit permeation resistance of PE/MPAEVOH bottles at 40°C improved by more than 3000 times compared to the PE bottle, wherein the best permeation resistance (4200 times barrier improvement) of the PE/MPAEVOH bottles was found as the weight ratio of MPA : EVOH reached 4:1. These interesting permeation properties of PE/MPAEVOH bottles were investigated in terms of the barrier and free‐volume properties of the base resins and their corresponding morphologies in blow‐molded bottles. POLYM. ENG. SCI. 45:25–32, 2005. © 2004 Society of Plastics Engineers.
Microstructure and crystallography in microcellular injection‐molded polyamide‐6 nanocomposite and neat resin
Authors: Chandra Alexander , Gong Shaoqin , Yuan Mingjun , Turng Lih‐Sheng , Gramann Paul , Cordes Holger
Published: December 2004

The effects of adding nanoclay to polyamide‐6 (PA‐6) neat resin, and the effects of processing parameters on cell density and size in microcellular injection‐molded components were investigated. In addition, the crystal sizes, structures, and orientation were analyzed with the use of x‐ray diffraction (XRD) and a polarized optical microscope. The standard ASTM D 638‐02 tensile bars for the analyses were molded according to a fractional four‐factor, three‐level, L9 Taguchi design of experiment (DOE) with varying melt temperature, injection speed, supercritical fluid (SCF) concentration, and shot size. It was found that the presence of montmorillonite (MMT) nanoclay greatly reduced the size of the cells and crystals, but increased their density in comparison with neat resin processed under identical molding conditions. In addition, at the sprue section downstream of the machine nozzle, cell size gradually decreased from the part center toward the skin for both the neat resin and the nanocomposite. It was also found that shot size was the most important processing parameter for both the neat resin and nanocomposite in affecting cell density and size in microcellular injection molding components. Weakly preferred crystal orientations were observed on the surface of microcellular injection‐molded PA‐6/MMT tensile bars. Finally, the addition of nanoclay in PA‐6 neat resin facilitated the formation of γ‐phase crystals in the molded components. Polym. Eng. Sci. 45:52–61, 2005. © 2004 Society of Plastics Engineers.
Spherulitic crystallization behavior of linear low‐density polyethylene
Authors: Feng L. , Kamal M.R.
Published: December 2004

In this study the crystallization behavior of linear low‐density polyethylenes (LLDPEs) (ethylene‐α‐olefin copolymers) was studied by polarized light microscopy. A modified Hoffman‐Lauritzen (MHL) expression is proposed whereby the equilibrium melting temperature, T (T), is replaced with the melting temperature of the crystal stem is replaced with the maximum possible stem length, T. It successfully describes the crystalline spherulitic growth kinetics for both homogeneous and heterogeneous LLDPEs. In addition to regimes III and II, another regime (IM) was found in the high crystallization temperature range. Linear growth behavior of crystalline spherulites was observed in regime III, and nonlinear growth behavior was found in regimes II and IM. The basal surface free energy can be estimated from the short chain branching polydispersity (SCBP) for LLDPEs with excluded comonomers. Polym. Eng. Sci. 45:74–83, 2005. © 2004 Society of Plastics Engineers.
Relationship between the rheology and morphology of dynamically vulcanized thermoplastic elastomers based on EPDM/PP
Authors: Goharpey F. , Nazockdast H. , Katbab A.A.
Published: December 2004

Relationship between the rheological properties and morphology of dynamically vulcanized thermoplastic elastomers (TPVs) based on Ethylene Propylene Diene Monomer (EPDM) and Polypropylene (PP) blends containing 20, 40 and 60% of EPDM were studied. The samples were prepared in a laboratory internal mixer at a rotor speed of 60 rpm. We performed morphological studies on the cryogenically fractured samples using scanning electron microscopy (SEM). The rheological behavior and melt viscoelastic properties of the samples were studied by rheometric mechanical spectrometry (RMS) at a temperature of 220°C. The TPV samples showed a significant viscosity upturn and a strong storage modulus that tended to plateau at low shear rates, with the highest extent for the sample containing 60% of EPDM. These results were attributed to a network structure resulting from agglomerates formed between the cured rubber particles, as evidenced by the morphological features of the samples. The multiple elastic response, expressed in terms of relaxation time distribution, H(λ), exhibited by the molten TPV sample containing 60% of EPDM suggests that apart from the contribution of flow‐induced molecular orientation of the PP matrix, there may also exist some elastic response induced by agglomerates formed between the cured rubber particles. The results predicted from the linear viscoelastic model proposed in the present work were found to be in good agreement with the experimental results. POLYM. ENG. SCI. 45:84–94, 2005. © 2004 Society of Plastics Engineers.
Cyclic deformation behavior of an epoxy polymer. Part II: Predictions of viscoelastic constitutive models
Authors: Xia Zihui , Shen Xinghe , Ellyin Fernand
Published: December 2004

The experimental results presented in Part I of this study were used to evaluate the predictive capabilities of two viscoelastic constitutive models. One of the models, developed by Xia and Ellyin, is in a differential form. The other, which is a modified Schapery model by Lai and Bakker, is in an integral form. The results of the comparison indicate that the Xia‐Ellyin constitutive model simulated the experimental observations well. This was attributed to the existence of a general rule that delineates the loading and unloading parts of the cyclic response. The modified Schapery model was able to predict the general trends of the deformation behavior; however, it was unable to correctly simulate the unloading behavior. This difference became more pronounced when the applied cyclic stress/strain was high. At high applied loads, the material response became more nonlinear. POLYM. ENG. SCI. 45:103–113, 2005. © 2004 Society of Plastics Engineers
Study of the molecular configuration and the dipole moment in fluorinated liquid crystals
Authors: Liu Yufang , Ma Heng , Xu Houju , Sun Jinfeng , Han Keli
Published: December 2004

We have investigated the relationship between the molecular configuration and dipole moment of some fluorinated liquid crystals (LCs). The geometries of the molecules were preliminarily optimized at empirical AM1 and then were further optimized at B3LYP/6‐31G(d) level. The dipole moment has been calculated. It is strongly influenced by the position and number of fluorine substituents in the benzene ring of the molecule. The polarizability, mean polarizabilities, and anisotropic polarizability of the phenylbicyclohexane (PBC) fluorine substituents are also given and discussed. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Study of Starch Granules Swelling by the Blue Dextran Method and by Microscopy
Authors: Contreras López Elizabeth , Rolée Arnaud , Le Meste Martine
Published: December 2004

The evolution of corn and wheat starch granules swelling at different temperatures was determined by two techniques: the blue dextran method (which measures the swelling factor) and by optical (light) microscopy. The graphical results obtained using the blue dextran technique showed curves indicating the swelling of corn and wheat starch dispersions (at 64%, w/w, moisture content) characterized by an initial phase of slight swelling, a second phase of fast swelling and a final phase of maximum swelling. The concentrated solutions (42% and 47%, w/w, moisture content) showed a slight swelling with the increase in temperature. The effect of temperature on the shape of the granules was evaluated by the optical microscopy. The shape of the type A wheat starch granules was deformed at high temperatures. The corn and type B wheat granules had a spherical form. In the case of corn starch, a good correlation (r2= 0.929) was obtained between the results of optical microscopy and blue dextran techniques.
Build to order supply chains in developed and developing countries
Authors: Prasad Sameer , Tata Jasmine , Madan Manu
Published: December 2004

The new competitive environment requires firms to produce products with greater specificity to customer needs. Traditional approaches historically employed by manufacturers, such as the use of planning bills and standard interactions among suppliers and buyers, may not prove to be as effective in this new environment. In our research, we first seek to differentiate the traditional Made to Stock (MTS) environment from the emerging Build to Order (BTO) one. In addition, given the global nature of supply chains today, we also compare BTO operations in developed countries with those in the developing world. The results from this study can be useful to practicing managers because we provide specific directions on aligning supply chains for the BTO environment across the globe. In addition, this research adds to the theoretical development of postponement strategies in manufacturing, and establishes empirical links between the international operations, build to order environment, and supply chain literatures.
Satellite measurements of NO2 from international shipping emissions
Authors: Richter Andreas , Eyring Veronika , Burrows John P. , Bovensmann Heinrich , Lauer Axel , Sierk Bernd , Crutzen Paul J.
Published: December 2004

Measurements from the SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY) instrument on board the ENVISAT satellite have been analyzed for tropospheric NO2 signatures of shipping emissions. Clear indication for NO2 produced from ship emissions has been found over the Red Sea and along the main shipping lane to the southern tip of India, to Indonesia and north towards China and Japan where the signal is lost. Using simple assumptions for the NOx loss, emission strengths were estimated and compared to an updated ship emission inventory. Good agreement was found in the spatial distribution and the absolute values for the Red Sea agree within a factor of 2, but larger discrepancies exist in other areas. Although the fluxes calculated still have large uncertainties, the results highlight the importance of ship emissions for the marine boundary layer and at the same time demonstrate the potential of satellite observations.
Atmospheric circulation and cyclone frequency variations linked to the primary modes of Greenland snow accumulation
Authors: Rogers Jeffrey C. , Bathke Deborah J. , Mosley‐Thompson Ellen , Wang Sheng‐Hung
Published: December 2004

Data from 34 Greenland firn cores, extending from 1982 to 1996, are used to identify spatial accumulation variability patterns and their associated atmospheric circulation and cyclone frequencies. The first principal component, representing west‐central Greenland accumulation, is correlated to NAO variability, having increased southwesterly (northeasterly) flow over that area during high (low) accumulation winters. The flow is linked to a relative increase in cyclone activity on the west central region of the ice sheet during high accumulation periods. The second principal component represents accumulation over southeastern Greenland where strong westerly flow leads to high accumulation and an increase in lee cyclones on the east and southeast coast. The study provides evidence that increased cyclone activity occurs over, or immediately adjacent to, areas experiencing anomalously high accumulation and it is important to distinguish lee cyclones from “Icelandic” cyclones, as they produce opposite precipitation effects over the ice sheet.
A linear tendency correction technique for improving seasonal prediction of SST
Authors: Barreiro Marcelo , Chang Ping
Published: December 2004

A methodology is presented to linearly correct the tendency of sea surface temperature (SST) anomalies in a coupled model. Using an atmospheric general circulation model (AGCM) coupled to a slab ocean as an example, we demonstrate the effectiveness of the linear correction methodology in improving the model's skill predicting SST in the tropical Atlantic Ocean during boreal spring. For this particular coupled model, the correction mainly takes into consideration the linear ocean dynamics absent in the slab ocean, thereby improving the skill in the tropical south and equatorial Atlantic. The corrected coupled model is further shown to produce a skillful rainfall forecast in the intertropical convergence zone (ITCZ) region during the boreal spring.
Observing and assessing nontidal ocean loading using ocean, continuous GPS and gravity data in the Adriatic area
Authors: Zerbini S. , Matonti F. , Raicich F. , Richter B. , van Dam T.
Published: December 2004

The effect of nontidal ocean loading (NTOL) is observed in the height series of four permanent GPS stations in the northern Adriatic. A validation of the ECCO model is performed by comparing model estimates of sea‐level anomalies from tide‐gauges with TOPEX/POSEIDON data, and ECCO model estimates of bottom pressure with those derived from temperature and salinity observations. The amplitudes of the ECCO sea‐level anomaly are found to be 1.4 times smaller than observations; bottom pressure is 2 times smaller. Using a Green's functions approach to determine elastic deformations, the ECCO ocean bottom pressure is used to estimate surface displacements at the GPS sites. Model results were compared with the height series and with the observed NTOL effect. The height series and the predicted NTOL are highly correlated at all four stations. The analysis performed on superconducting gravimeter data at the Medicina station also shows high correlation.
The evolution of the seismic‐aseismic transition during the earthquake cycle: Constraints from the time‐dependent depth distribution of aftershocks
Authors: Rolandone F. , Bürgmann R. , Nadeau R. M.
Published: December 2004

Using the example of the 1992 M 7.3 Landers earthquake, we show that in the aftermath of a large earthquake the depth extent of aftershocks shows an immediate deepening from pre‐earthquake levels, followed by a time‐dependent postseismic shallowing. We use these seismic data to constrain the change in the depth of the seismic‐aseismic transition with time throughout the earthquake cycle. Most studies of the seismic‐aseismic transition have focussed on the effects of temperature and/or lithology on the transition either from brittle faulting to viscous flow or from unstable to stable sliding. A strain‐rate dependent transient deepening of the brittle‐ductile transition following a major earthquake is predicted by geological and laboratory observations. By analyzing the time‐dependent depth distributions of aftershocks, we identify and quantify the temporal evolution of this transition. In the example of the Landers earthquake, its depth changes by as much as 3 km over the course of 4 years.
Lagged relationships between ENSO and the Asian Summer Monsoon in the CSIRO coupled model
Authors: Kawamura Ryuichi , Suppiah Ramasamy , Collier Mark A. , Gordon Hal B.
Published: December 2004

The lagged relationship between the El Nino‐Southern Oscillation (ENSO) and Asian Summer Monsoon (ASM) variability is investigated using the Commonwealth Scientific and Industrial Research Organization (CSIRO) Mark3 coupled model. Composite analyses of 17 warm and 16 cold events from an extended unforced run reveal that the model captures the asymmetric structures of rainfall and SST anomalies over the tropical Indian Ocean during northern hemisphere spring which is one of the major precursory signals of anomalous ASM variability. As a remote forcing mechanism prior to the ASM onset, simulated anomalous convection over the northern Indian Ocean strongly influences the land surface hydrologic conditions over central and southwest Asia. Simulated land‐surface processes result in anomalous temperatures over the land, which in turn produce a change in the land‐ocean thermal contrast over the domain. The results are consistent with observed features, which show a delayed and indirect impact of ENSO on the ASM variability during the early summer monsoon period, but not during the rest of the monsoon season.
290
fs
switching time of Fe-doped quantum well saturable absorbers in a microcavity in 1.55μm range
Authors: Gicquel-Guézo M. , Loualiche S. , Even J. , Labbé C. , Dehaese O. , Le Corre A. , Folliot H. , Pellan Y.
Published: December 2004

Ultrafast all-optical switch has been demonstrated by inserting Fe-doped multiple quantum wells (MQWs) in asymmetric Fabry-Perot microcavities. Heavy Fe doping during the InGaAs∕InP MQW epitaxial growth is a well-controlled technique to reach subpicosecond optical time constants. An asymmetric Fabry-Perot microcavity using gold metal as a back mirror and air/InP interface as a front mirror is realized. Pump-probe experiments using a conventional scheme on such switching devices are investigated. The device reveals an ultrafast response time, as low as 290fs, for an iron concentration of 2×1019cm−3, a contrast ratio of 8dB, a threshold switching fluence of 3.5μJ∕cm−2, and a 37-nm 3-dB bandwidth in the 1.55-μm telecommunication spectral range.
Directional growth by low electric-field-controlled crystallization of bulk amorphous lithium tetraborate
Authors: Kim S. J. , Kim J. E. , Yang Y. S.
Published: December 2004

Highly oriented rod-shaped crystals were grown during crystallization of bulk amorphous Li2B4O7 under a low ac electric field of ∼5V∕mm. The crystal c axis that is the long direction of rods and perpendicular to the flat surface of the sample is parallel to the applied electric-field direction. The oriented crystals, with an alignment within a declined angle of ∼15°, are so long along the c direction compared with those of other directions that the geometrical structure of each rod is quasi-one-dimensional. The measured electromechanical coupling coefficient of kt=0.47 is comparable to that of single-crystal Li2B4O7.
Thermoelectric figure of merit of II–VI semiconductor nanowires
Authors: Mingo N.
Published: December 2004

The room temperature thermoelectric figure of merit and power factor are calculated for bulk and nanowires made of CdTe, ZnTe, ZnSe, and ZnS, of the zincblende structure. To this end, an iterative solution of the Boltzmann transport equation is used to obtain the electronic transport properties. The lattice thermal conductivity is estimated using a full dispersion transmission function approach. A saturation to finite values is predicted for the power factor in the small thickness limit. The figure of merit increase upon thickness reduction is largest for CdTe, followed by ZnTe, ZnSe, and ZnS. II–VI nanowires show smaller increases of the figure of merit as compared with III–V nanowires, despite their bulk values are of comparable magnitude in the two groups. The reasons for this are explained.
Columnar [001]-oriented nitrogen order in Ga(NAs) and (GaIn)(NAs) alloys
Authors: Rubel O. , Volz K. , Torunski T. , Baranovskii S. D. , Grosse F. , Stolz W.
Published: December 2004

By calculations in the framework of the valence force field method, we show that nitrogen atoms in diluted GaAs1−xNx tend to align along the [001] direction. In quaternary alloys Ga1−yInyAs1−xNx this tendency is observed only in “as-grown” samples, while in the annealed samples nitrogen atoms build more energetically favorable bonds with indium. Experimentally observed inhomogeneous strain profiles in these material systems, as well as their dissolution upon annealing, agree qualitatively with results of the calculations.
Capture and release of photonic images in a quantum well
Authors: Krauß J. , Kotthaus J. P. , Wixforth A. , Hanson M. , Driscoll D. C. , Gossard A. C. , Schuh D. , Bichler M.
Published: December 2004

The capture of an optical image in the plane of a semiconductor quantum well and the subsequent re-emission of this image in the form of a two-dimensional photon flux is demonstrated. Spatially resolved storage of photonic signals in a two-dimensional lateral potential landscape of the quantum well is employed to imprint optical images in the form of trapped photogenerated charges into the solid. The lateral two-dimensional potential modulation leads to very long storage times by a deliberate spatial separation of photogenerated electron–hole pairs. Once the potential modulation is lifted, the initial optical information is restored and the photographed image is released in a flash of light.
Current-induced spin polarization at a single heterojunction
Authors: Silov A. Yu. , Blajnov P. A. , Wolter J. H. , Hey R. , Ploog K. H. , Averkiev N. S.
Published: December 2004

We have experimentally achieved spin polarization by a lateral current in a single nonmagnetic semiconductor heterojunction. The effect does not require an applied magnetic field. The current-induced spin orientation can be seen as the inverse of the circular photogalvanic effect (also often referred to as spin photocurrents): the nonequilibrium spin changes its sign as the current reverses.
One-dimensional ultrasound receive array using spectrally encoded optical detection
Authors: Buma T. , O’Donnell M.
Published: December 2004

An ultrafast Ti:Sapphire laser and a Sagnac interferometer are combined for optical detection of ultrasound. Distinct spatial positions are probed simultaneously by different wavelengths within the broadband laser. Ultrasonic signals from each probe position are derived from the spectrum of the reflected light. The same single-mode fiber delivers incident and reflected light. A one-dimensional receive array is demonstrated by measuring the acoustic field of a spherically focused piezoelectric transducer. This is a promising form of parallel detection for miniaturized high-frequency ultrasonic arrays.
Chemical reaction and metallic cluster formation by annealing-temperature control in ZrO2 gate dielectrics on Si
Authors: Okabayashi J. , Toyoda S. , Kumigashira H. , Oshima M. , Usuda K. , Niwa M. , Liu G. L.
Published: December 2004

Thermal stability of the ZrO2∕Zr–silicate∕Si structure and the Zr–silicide formation were investigated by photoemission spectroscopy depending on the annealing temperature in ultrahigh vacuum. By the annealing below 860°C, the interfacial layer thickness of the Zr–silicate decreased although the ZrO2 top layer was not affected. The annealing at 860°C caused the interfacial Zr–silicate layer to disappear. By the annealing above 860°C, the metallic Zr components appeared and the metallic clusters were formed. High-resolution photoemission spectra have revealed that the clusters consist of a ZrSi2 layer. Valence-band spectra depending on the annealing temperature provide us with the information about the crystallization in the ZrO2 layer.
Shockley partial dislocations to twin: Another formation mechanism and generic driving force
Authors: Wang Jian , Huang Hanchen
Published: December 2004

We report a mechanism of twin formation from two Shockley partial dislocations on non-neighboring glide planes. Further, we correlate the driving force of twin nucleation with the local stress of large magnitude. Using the embedded atom method potential for atomic interactions, our molecular dynamics simulations of Cu nanograins and a single crystal reveal the formation mechanism and identify the driving force. Stacking faults expand under high stress, increasing their energy and making their transformation to a twin energetically favorable. Although this study focuses on only Shockley partial dislocations on non-neighboring glide planes, the driving force—the stress of large magnitude—is expected to apply also to the twin formation from Shockley partial dislocations on neighboring glide planes.
Resonance enhanced THz generation in electro-optic polymers near the absorption maximum
Authors: Sinyukov Alexander M. , Leahy Megan R. , Hayden L. Michael , Haller Marnie , Luo Jingdong , Jen Alex K-Y. , Dalton Larry R.
Published: December 2004

The electro-optic (EO) coefficient of an organic nonlinear material exhibits a sharp resonance near the absorption maximum of the material. Due to this resonance, we experimentally observe the amplitude of the THz field generated from a 3.1-μm-thick EO polymer composite to be larger than that emitted from a 1000-μm-thick crystal of ZnTe. This comparison allows us to estimate the resonance enhanced EO coefficient of the polymer composite to be over 1250pm∕V at 800nm.
Laser writing of semiconductor nanoparticles and quantum dots
Authors: Bertino M. F. , Gadipalli R. R. , Story J. G. , Williams C. G. , Zhang G. , Sotiriou-Leventis C. , Tokuhiro A. T. , Guha S. , Leventis N.
Published: December 2004

Silica aerogels were patterned with CdS using a photolithographic technique based on local heating with infrared (IR) light. The solvent of silica hydrogels was exchanged with an aqueous solution of the precursors CdNO3 and NH4OH, all precooled to a temperature of 5°C. Half of the bathing solution was then replaced by a thiourea solution. After thiourea diffused into the hydrogels, the samples were exposed to a focused IR beam from a continuous wave, Nd-YAG laser. The precursors reacted in the spots heated by the IR beam to form CdS nanoparticles. We lithographed features with a diameter of about 40μm, which extended inside the monoliths for up to 4mm. Samples were characterized with transmission electron microscopy and optical absorption, photoluminescence, and Raman spectroscopies. Spots illuminated by the IR beam were made up by CdS nanoparticles dispersed in a silica matrix. The CdS nanoparticles had a diameter in the 4–6nm range in samples exposed for 4min to the IR beam, and of up to 100nm in samples exposed for 10min.
Tb nanocrystalline array assembled directly from alloy melt
Authors: Wang Y. T. , Xi X. K. , Fang Y. K. , Zhao D. Q. , Pan M. X. , Han B. S. , Wang W. H. , Wang W. L.
Published: December 2004

A two-dimensional (2D) thin film composed of Tb nanocrystals with uniform orientations is fabricated directly from Tb65Fe25Al10 alloy melt upon quenching. The Tb nanocrystals with vertical height of 15–30 nm and lateral width of 10–20 nm are assembled in the nanocrystalline array on an amorphous substrate. The formation mechanism for the aligned Tb nanocrystals is discussed. The single-step formation method may provide a new and flexible alternative to fabricate nanostructured films or arrays used for submicron devices.
Transplanting carbon nanotubes
Authors: El-Aguizy Tarek A. , Jeong Jeung-hyun , Jeon Yong-Bae , Li W. Z. , Ren Z. F. , Kim Sang-Gook
Published: December 2004

Current efforts of guided growth of carbon nanotubes alone cannot make large-scale and directed assembly of them. The nanopelleting concept overcomes this limitation by embedding carbon nanotubes in microscale pellets that can be transplanted readily. This technique includes vertical growth of carbon nanotubes, pellet casting, planarization, pellet separation, and transplantation. A specific manufacturing process is developed and tested with favorable results. This technology will enable directed assembly of carbon nanotubes in a long-range order.
Piezoresistive detection-based ferromagnetic resonance force microscopy of microfabricated exchange bias systems
Authors: Volodin A. , Buntinx D. , Brems S. , Van Haesendonck C.
Published: December 2004

Ferromagnetic resonance measurements were performed on CoO∕Co exchange biased microstructures with a low-temperature magnetic resonance force microscope (MRFM). The MRFM instrument relies on piezoresistive force detection, and the magnetic tip attached to the cantilever acts as a field gradient source. These features extend the applicability of the MRFM that can also be used as a conventional magnetic force microscope. Spatial variations of the MRFM signal, which are induced by a spatially modulated exchange bias, are monitored with a lateral resolution of about 5μm.
Naturally occurring, optically driven, cellular rotor
Authors: Dharmadhikari J. A. , Roy S. , Dharmadhikari A. K. , Sharma S. , Mathur D.
Published: December 2004

We report the conversion of optical energy into mechanical energy by naturally occurring red blood cells (RBCs) placed in an optical trap. A trapped RBC undergoes folding due to the elastic nature of its cell membrane. On use of circularly polarized light in the trap, the folded RBCs rotate, indicating their birefringence. The cellular rotation speed depends on the size of the blood cells and on laser power. Rotating RBCs have implications for naturally occurring, optically driven, rotary micromachines.
Otherwise than Becoming: Jean Rouch and the Ethics of
Les Maîtres fous
Authors: Cooper Sarah
Published: December 2004

This article focuses on Jean Rouch's celebrated documentary
Les Maîtres fous
. Rouch's commentary to the film encourages us to view the performances we witness as 'le reflet de notre civilisation'. Following Rouch, many critics of this film have focused on the imitative, reflective aspects of the relationship between colonizer and colonized that it lays bare. In its willed conflation of positions, however, I argue that the mimetic relations that Rouch encourages us to see are problematic in a way that the film more generally, when read against the logic he proposes, is not. Gilles Deleuze is one commentator who has sought to move beyond mimesis when discussing Rouch's filmmaking, yet in his analysis Deleuze's non-imitative approach shades into its opposite, requiring us to look elsewhere in order to describe the filmic logic that moves us beyond imitation. In his attention to marking out a space for alterity that lies outside the sphere of the self-same, it is Emmanuel Levinas's work that enables us ultimately to account for a non-imitative ethics in
Les Maîtres fous
.
THE
LAI DE L’OISELET
, THE
PROVERBES AU VILAIN
AND THE PARABLE OF THE SOWER
Authors: Burch Sally L.
Published: December 2004

The
Lai de l’oiselet
is an expanded version of a tale from the
Disciplina clericalis
, in which the protagonists are a peasant and a bird. The
lai
differs from the
Disciplina
in interpreting the narrative as a contest between
courtoisie
and
vilenie
. The peasant is no longer a simple
rusticus
, but an embodiment of the coarseness and stupidity associated with the
vilain
. A particular thrust of the narrative attack on the
vilain
is connected with the
Proverbes au vilain
. The
Lai
signals the thematic importance of proverbs by its remarkably high concentration of proverbial material. The text demonstrates to its courtly audience that a
vilain
has no entitlement to be considered a source of proverbial wisdom. The
vilain
is textually dispossessed of ‘his’ proverbs. A further intertext is the gospel commentary on the Parable of the Sower, which authorizes the dispossession of ‘him who has not’. Thus an intertextual reading of the
Lai de l’oiselet
reveals the full scope of the work’s attack on
vilenie
, and its attempt to reclaim for
courtoisie
the territory of proverbial wisdom, attributed to the
vilain
by such texts as the
Proverbes au vilain
.
The Specific Plurality of Assia Djebar
Authors: Hiddleston Jane
Published: December 2004

Recent postcolonial criticism suffers from a sense of anxiety regarding the appropriate balance between cultural specificity and post-identitarian hybridity or ‘creolisation’. Thinkers differ in their understanding of the importance of identity, at times advocating that the affirmation of a particular subject position is the only means of resisting (neo)colonial domination, and at others asserting that a celebration of relationality and cultural plurality can serve to critique entrenched power relations. Conceptions of postcolonial resistance waver between the urge to privilege an alternative, monologic identity on the one hand, and liberation through the dissolution of all specified identity categories on the other. The apparently stark opposition between these two modes of thought demands, however, to be unsettled and rendered more subtle. I want to use the texts of Assia Djebar, with reference also to the theories of Jean-Luc Nancy and Peter Hallward, to rework the terms of this debate. Rather than championing exclusively either cultural specificity or trans-culturation, Djebar’s work incorporates a continued struggle between the specific, the singular and the plural. First, Djebar’s texts set out to unveil or conceive a feminine Algerian identity, rescuing Algerian women from occlusion both by colonialism and by Islamic law and giving voice to their repressed specificity. Despite her belief in the necessity of this project, however, she finds that it is troubled on two levels. On the one hand, the desire to retrieve some particular essence results in the continual retreat of that essence, and the more the texts hope to uncover, the more they inadvertently mask or hide. Algerian identity is replaced, therefore, with a sense of the intractable singularity of the occluded ‘self’. Furthermore, this singularity turns out to be not absolute but composite, as the erasure of the subject is coupled with a proliferation of diverse traces and echoes. The quest for identity intermittently dissolves, and Djebar displays postcolonial experience in Algeria instead as a curious coalescence of intractable singularity and ongoing intercultural plurality.
Clobazam as a New Antiepileptic Drug and Clorazepate Dipotassium as an Alternative Antiepileptic Drug in Japan
Authors: Sugai Kenji
Published: December 2004

Summary:  Purpose: To confirm the efficacy and to clarify the problems of clobazam (CLB) as a new antiepileptic drug (AED) and clorazepate (CLP) as an alternative AED in Japan.

Methods: CLB and CLP were added on or replaced with conventional AEDs in 55 and 170 patients with refractory epilepsies, respectively. Short‐term efficacy was studied after at least 2 months of CLB administration and at least 4 weeks of CLP administration. Long‐term efficacy was examined in 31 cases with CLB for ≥6 months and in 86 cases with CLP for ≥6 months. CLB was initiated at 0.15–0.40 mg/kg and increased by 0.1–0.2 mg/kg every 1–2 weeks up to 0.28–1.25 mg/kg. CLP was started at 0.3–0.7 mg/kg and increased by 0.2–0.3 mg/kg every 1–2 weeks up to 2.5 mg/kg. Tolerance was examined in 42 cases with CLB for ≥3 months and 112 cases with CLP for ≥4 weeks.

Results: CLB was effective, defined as ≥50% reduction in seizure frequency, in 71% of the short‐term subjects and 81% of the long‐term subjects. Short‐term efficacy was better in symptomatic localization‐related epilepsies, but long‐term efficacy did not differ according to seizure classification. Short‐term efficacy was not different by seizure types or EEG findings. CLP was effective in 70% of the short‐term subjects and 80% of the long‐term subjects. CLP was more effective in patients with localization‐related epilepsies or in patients with partial seizures or focal epileptiform discharges on EEG. Adverse effects developed in 47% of CLB cases and 31% of CLP cases, but the incidence was reduced by lower initial doses and slow dose titration. Tolerance occurred in 24% of CLB cases and 48% of CLP cases, half within 3–4 months after the initiation of CLB and half by 2 months after the start of CLP. Upon rechallenge, 70% of CLB‐tolerant cases and 50% of CLP‐tolerant cases responded to each drug again by increasing or maintaining the dosage.

Conclusions: Excellent efficacy of CLB and excellent and prolonged efficacy of CLP for refractory epilepsies were confirmed. Frequent tolerance and adverse effects were major problems, but were manageable.
Statistics on Deliveries of Mothers with Epilepsy at Yokohama City University Hospital
Authors: Endo Seiji , Hagimoto Hiroshi , Yamazawa Hiroshi , Kajihara Satoshi , Kubota Shinji , Kamijo Atsushi , Nakajima Kaori , Furusho Ryo , Miyauchi Toshiro , Endo Masaya
Published: December 2004

Summary:  Purpose: To survey and summarize the treatment of pregnant women with epilepsy and to obtain data for the improvement of daily treatment regimens.

Methods: We reviewed medical records of 36 deliveries of 25 mothers with epilepsy at Yokohama City University Hospital from September 1991 to December 2000 and statistically compared the differences in drug‐taking profiles, complications during pregnancy, types of delivery, and complications at delivery between the epilepsy group and a control group (656 total deliveries after 22 weeks except for epilepsy cases in 1991 and 1992 at Yokohama City University Hospital).

Results: Of the 25 mothers with epilepsy, three with idiopathic generalized epilepsy, 12 were symptomatic for partial epilepsy. Their mean age at delivery was 29.0 years. The mean age at onset of epilepsy was 13.9 years. Of the 36 pregnancies, 30 (83.3%) cases continued antiepileptic drug (AED) taking throughout the pregnancies; 23 (63.9%) cases received monotherapy. Phenobarbital was the most frequently used drug in monotherapies. Seven (19.4%) cases received polytherapy. Seven (19.4%) patients experienced epileptic seizures during pregnancy. One case showed a low serum AED level. No statistically significant difference was found in complications during pregnancy, types of delivery, or complications at delivery, excluding abnormal rotation in the birth canal. Congenital malformation (cleft lip with palate) was observed in one (2.9%) case. The mother was 39 years old at delivery and had myoma uteri. Onset of epilepsy was at 14 years. She had been taking three kinds of AEDs: 1,400 mg/day of sodium valproate (VPA), 1.5 mg/day of clonazepam (CZP), and 200 mg/day of zonisamide (ZNS). Serum concentrations at pregnancy week 10 were 85.3 μg/ml VPA, 18.1 μg/L CZP, and 10.5 μg/ml ZNS. She also had been taking folic acid, 5 mg/day, but the serum concentration was not measured.

Conclusions: The method of treatment and the management of pregnancy were left to the discretion of each doctor. However, in most cases, monotherapy was selected; and the frequency of complications was not significantly different from that of the control group, excluding the frequency of abnormal rotation in the birth canal. However, we could have been more proactive in calculating the risks of pregnancy for women with epilepsy and adjusted treatment in anticipation of a planned pregnancy, before the patient actually became pregnant. Additionally, a closer working relationship between the obstetrician and the physician who treats the epilepsy would seem to be a further requirement for the patient's well‐being, as well as her child's, during pregnancy.
Marital Status of Patients with Epilepsy with Special Reference to the Influence of Epileptic Seizures on the Patient's Married Life
Authors: Wada Kazumaru , Iwasa Hiroto , Okada Motohiro , Kawata Yuko , Murakami Takuya , Kamata Akihisa , Zhu Gang , Osanai Takao , Kato Takuhiko , Kaneko Sunao
Published: December 2004

Summary:  Purpose: We investigated the marital status of the patients with epilepsy to clarify the clinical factors impeding improvement of the quality of life in adults with epilepsy.

Methods: We examined the marital status of adult patients with epilepsy who did not have mental retardation and had been treated at Hirosaki University Hospital, Hirosaki, Japan, for >5 years. The present study included 278 patients (142 men and 136 women) ranging from age 20 to 60 years.

Results: Sixty‐six men and 52 women were single. Seventy‐six males and 84 females had been married. The present study investigated the proportion of patients in whom seizures were controlled at the time of marriage. Percentages were only 30% for men and 22% for women. This result showed that in many patients, seizures were not controlled when they were married, which suggests that seizures themselves may not markedly inhibit marriage. Thirteen men and 16 women (total, 29 patients) had experienced divorce. Epilepsy was the cause of divorce in seven of the 29 patients who had been divorced. Of these seven patients, only one patient had informed the spouse of the disease before marriage. In the remaining six patients, seizures were witnessed after marriage or the disease was revealed by medication, which resulted in divorces.

Conclusions: Concerning the association between marriage and the job, a close relation was found between the presence or absence of marriage and the presence or absence of a job among male patients.
Using ecological restoration to constrain biological invasion
Authors: BAKKER JONATHAN D. , WILSON SCOTT D.
Published: December 2004

Biological invasion can permanently alter ecosystem structure and function. Invasive species are difficult to eradicate, so methods for constraining invasions would be ecologically valuable. We examined the potential of ecological restoration to constrain invasion of an old field by Agropyron cristatum, an introduced C3 grass.

A field experiment was conducted in the northern Great Plains of North America. One‐hundred and forty restored plots were planted in 1994–96 with a mixture of C3 and C4 native grass seed, while 100 unrestored plots were not. Vegetation on the plots was measured periodically between 1994 and 2002.

Agropyron cristatum invaded the old field between 1994 and 2002, occurring in 5% of plots in 1994 and 66% of plots in 2002, and increasing in mean cover from 0·2% in 1994 to 17·1% in 2002. However, A. cristatum invaded one‐third fewer restored than unrestored plots between 1997 and 2002, suggesting that restoration constrained invasion. Further, A. cristatum cover in restored plots decreased with increasing planted grass cover. Stepwise regression indicated that A. cristatum cover was more strongly correlated with planted grass cover than with distance from the A. cristatum source, species richness, percentage bare ground or percentage litter.

The strength of the negative relationship between A. cristatum and planted native grasses varied among functional groups: the correlation was stronger with species with phenology and physiology similar to A. cristatum (i.e. C3 grasses) than with dissimilar species (C4 grasses).

Richness and cover of naturally establishing native species decreased with increasing A. cristatum cover. In contrast, restoration had little effect on the establishment and colonization of naturally establishing native species. Thus, A. cristatum hindered colonization by native species while planted native grasses did not.

Synthesis and applications. To our knowledge, this study provides the first indication that restoration can act as a filter, constraining invasive species while allowing colonization by native species. These results suggest that resistance to invasion depends on the identity of species in the community and that restoration seed mixes might be tailored to constrain selected invaders. Restoring areas before invasive species become established can reduce the magnitude of biological invasion.
The role of industrial fisheries and oceanographic change in the decline of North Sea black‐legged kittiwakes
Authors: FREDERIKSEN MORTEN , WANLESS SARAH , HARRIS MICHAEL P. , ROTHERY PETER , WILSON LINDA J.
Published: December 2004

Marine predators can be adversely affected by human activities in several potentially interacting ways. Industrial fisheries can affect predator populations adversely through competition for shared prey, and marine environmental change has also been implicated in population declines. In the North Sea, black‐legged kittiwakesRissa tridactylahave declined by > 50% since 1990, a period during which a lesser sandeelAmmodytes marinusfishery was active and profound oceanographic changes occurred. We studied the role of fisheries and oceanography in kittiwake declines on the Isle of May, south‐east Scotland, where sandeels are the main prey.

Demographic data were collected from 1986 to 2002. We examined changes over time and correlations between population parameters, the local sandeel fishery and environmental factors, and incorporated the results in a deterministic and a stochastic matrix population model.

Breeding success and adult survival were low when the sandeel fishery was active (1991–98) and were also negatively correlated with winter sea temperature, with a 1‐year lag for breeding success. Modelling showed that the observed changes in population parameters could explain the change in population growth rate from +8% year−1in the late 1980s to −11% year−1in the late 1990s. An observed improvement in breeding success from 2000 onwards has been insufficient to arrest the population decline. To stabilize the population, breeding success must increase to unprecedented levels or survival needs to increase substantially. Stochastic modelling indicated that the population was unlikely to increase if the fishery was active or sea temperature increased, and that the population was almost certain to decrease if both occurred.

Sandeel recruitment is reduced in warm winters, and we propose that this explains the temperature effects on kittiwake survival and breeding success. The fishery also had a strong effect on demographic performance, although the exact mechanism is unclear as kittiwakes and fishermen target different sandeel age groups.

Synthesis and applications. Poor breeding success of kittiwakes was associated with warm winters and the presence of a local sandeel fishery. Reversing the trend towards warmer winters may be impossible and, at best, would be a very slow process. Therefore, to safeguard kittiwake populations we recommend that the current closure of the commercial sandeel fishery remain in place indefinitely. This study shows that adequate monitoring of the effect of a fishery or of environmental change on seabird populations needs to include survival as well as breeding success.