bluuebunny/crossref_metadata_2025 huggingface dataset:
Yield design of dry‐stone masonry retaining structures—Comparisons with analytical, numerical, and experimental data
Authors: Colas A. S. , Morel J. C. , Garnier D.
Published: March 2008

Over the past few years, there has been a steady increase in the interest in dry‐stone walling not only to preserve existing constructions but also to build new ones. Yet, dry masonry's expansion is slowed down by the lack of scientific knowledge to assess its reliability. This study aims at contributing to the construction of this scientific frame using a simplified model based on yield design and homogenization, which can be directly exploited for engineering purposes. A new analytical expression of the ultimate load is thus established. Then, the validity of the method is assessed by comparisons with limit equilibrium analysis, distinct element method, and field trials. Finally, possible improvements of the model are discussed. Copyright © 2008 John Wiley & Sons, Ltd.
The Chinese version of ICIQ: A useful tool in clinical practice and research on urinary incontinence
Authors: Huang Liang , Zhang Song‐wen , Wu Shi‐liang , Ma Le , Deng Xiao‐hong
Published: March 2008

Aims

In China, more and more research on the management of urinary incontinence (UI) is being conducted; a robust questionnaire to evaluate the symptoms and impact of UI will be very helpful. Thus, the Chinese version of The International Consultation on Incontinence Questionnaire (ICIQ) was developed.

Methods

Initial translation and back translation of the ICIQ‐UI short form, the ICIQ‐FLUTS, the ICIQ‐FLUTS long form, the ICIQ‐LUTSqol, and the ICIQ‐FLUTSsex were completed by native Chinese and English speaker, respectively. Then, the psychometric properties of the Chinese version of the five ICIQ modules, including the content/face validity, internal consistency, and test–retest reliability were examined.

Results

The back translation of the questionnaires was consistent with the original English questionnaires. The Chinese version of the five ICIQ modules was easily completed, and the missing data were less than 2.5%. The Cornbach's alpha coefficient was 0.71–0.96. In the test–retest, the agreement rate of the two tests exceeded 95% and the kappa values were 0.72–0.93 (P < 0.001).

Conclusions

The Chinese version of the five ICIQ modules was easily understood, and had adequate internal consistency and reliability. It can be used in the study of Chinese‐speaking groups around the world. Neurourol. Urodynam. 27:522–524, 2008. © 2008 Wiley‐Liss, Inc.
Resource prediction and management in active networks
Authors: Devi K. Vimala , Mehata K. M. , Radhakrishnan S.
Published: March 2008

Active networks provide a programmable user–network interface that supports dynamic modification of the network's behavior. Network nodes, in addition to forwarding packets, perform customized computation on the messages flowing through them. Resources in an active network mainly consist of CPU and bandwidth. The inherent unpredictability of processing times of active packet poses a significant challenge in CPU scheduling. It has been identified that prior estimation of the resource requirements of a packet is very difficult since it is platform dependent and also depends on processing load at the time of execution, operating system scheduling, etc. An efficient allocation is required for the optimal utilization of resources. In this paper, resources are estimated using prediction techniques such as single exponential smoothing (SES), adaptive‐response‐rate single exponential smoothing (ARRSES) and Holt's two‐parameter estimation models. The estimated results agreed most with the actual requirements. The estimation models were compared with model criteria. An algorithm was also designed for the allocation of resources. Effectiveness of the algorithm was measured through simulation and achieved almost perfect fairness for all flows and also provided much superior delay guarantees under a highly dynamic environment. Copyright © 2008 John Wiley & Sons, Ltd.
EAS concept for higher‐order finite shell elements to eliminate volumetric locking
Authors: Hommel J.‐H. , Meschke G.
Published: March 2008

The deficiency of volumetric locking phenomena in finite elements using higher‐order shell element formulations based on Lagrangean polynomials and a linear finite shell kinematics cannot be avoided by the existent enhanced assumed strain (EAS) concept established for low‐order elements. In this paper a consistent modification of the EAS concept is proposed to extend its applicability to higher‐order shell elements. This modification, affecting the transversal normal strain for polynomial orders p>1, eliminates pathological modes caused by volumetric locking. The efficiency of the proposed extended EAS method is demonstrated by means of eigenvalue analyses and two representative numerical examples. Copyright © 2008 John Wiley & Sons, Ltd.
Multiobjective optimization of polymerization reaction of vinyl acetate by genetic algorithm technique with a new replacement criterion
Authors: Sadi Maryam , Dabir Bahram , Shahrabadi Abbas
Published: March 2008

A multiobjective optimization procedure based on genetic algorithm has been developed to determine optimum operational conditions of polymerization reaction. In this article by using a new selection criterion to choose the next generation members with better quality, optimization efficiency is improved and the number of generations to obtain Pareto optimal set reduced. In this proposed method a novel replacement criterion based on ranking level information and proximity of solutions to the Pareto optimal front is used to choose the next generation members. The polymerization of vinyl acetate has been chosen as an example. Two objective functions, which used in this study, are maximization of the weight average molecular weight up to the desired value and minimization of the residual initiator concentration. A Pareto optimal set of objective functions has been obtained by application of a Pareto set filter operator. Furthermore, the influence of genetic algorithm parameters on the efficiency and convergence of genetic algorithm is studied by changing cross over and mutation probabilities. Because of the flexibility and generality of genetic algorithm, this optimization method is a useful technique with lots of potentials in determination of optimum value of operation parameters. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Rheology and curing kinetics of fumed silica/cyanate ester nanocomposites
Authors: Goertzen William K. , Sheng Xia , Akinc Mufit , Kessler M.R.
Published: March 2008

A low‐viscosity bisphenol E cyanate ester (BECy) monomer was combined with fumed silica with average primary particle diameters of 12 and 40 nm to form high‐temperature adhesives with processability at ambient temperatures. Rheological evaluation revealed that for silica loadings below 15 vol%, suspensions of both particle sizes exhibited shear thinning and thixotropic behavior. Samples with high silica loadings (>15 vol%) of 40‐nm silica also showed intense shear thickening at shear rates above 10 s−1. Thixotropy was most pronounced for the 12‐nm silica, but the formation of a gel was slow, indicating that the polar nature of the BECy monomer was responsible for disrupting hydrogen bonds between silica particles. Rheokinetic evaluation of catalyzed samples showed that increasing silica content reduced gel time and increased gel viscosity, and this effect was most pronounced for the 12‐nm silica. Differential scanning calorimetry confirmed that the silica's hydroxyl groups have a minor catalytic effect on the polymerization kinetics, such that the activation energies of the catalyzed suspensions were decreased with increased nanoparticle loading and decreased particle size. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Preparation and characterization of functionalized low density polyethylene matrix biocomposites
Authors: Katsoulotos G. , Pappa G. , Tarantili P.A. , Magoulas K.
Published: March 2008

The incorporation of cellulosic fibers into polyethylene matrices was studied in this work, by dispersion of fluff pulp from maritime pine in a hot polymer solution, followed by co‐precipitation of the solid components by cooling at room temperature. The above method was found suitable for proper wetting and dispersion of fibers in the polymeric matrix, as compared with melt compounding. Unmodified low density polyethylene [LDPE], modified LDPE with maleic anhydride grafted linear low density polyethylene [M‐LLDPE] and a copolymer of acrylic acid and n‐butyl acrylate polyethylene [(AA/n‐BA)‐LDPE], were used as matrices for the preparation of fiber reinforced composites. The thermal properties of these composites were determined using differential scanning calorimetry and thermogravimetric analysis. The incorporation of cellulosic fibers results in a decrease of the crystallinity of the polymer matrix, as they act as inert material. In addition, the appropriate tests were run in order to determine the density and tensile properties of the composite specimens prepared by compression molding, with filler content ranging from 10 to 40% (w/w). Composites based on modified LDPE showed improved mechanical properties. The Takayanagi model, applied to predict the Young's modulus of composites, was in very good agreement with the experimental data obtained in this work. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Structure and properties of novel PMDA/ODA/PABZ polyimide fibers
Authors: Gao Guanqun , Dong Liang , Liu Xiangyang , Ye Guangdou , Gu Yi
Published: March 2008

A series of random copolyamic acid were synthesized from various ratios of two diamines 4, 4′‐oxydianiline (ODA) and 2‐(4‐aminophenyl)‐5‐aminobenzimidazole (PABZ) by polycondensation with pyromellitic dianhydride (PMDA) in N‐methyl‐2‐pyrrolidone (NMP). Their inherent viscosities were in the range of 1.89–2.91 dl/g. The polyamic acid (PAA) solution drops were spun into fibers by the wet spinning process. The polyimide (PI) fibers were obtained from PAA fibers after drawn and treated in heating tube. The fibers were characterized by fourier transform infrared (FTIR), wide X‐ray diffraction (WAXD), scanning electron microscope (SEM), thermal gravimetry analysis (TGA), dynamic mechanical analysis (DMA), and tensile testing. WAXD showed these PI fibers were basically amorphous. The tensile strength and initial modulus of the PI fiber reached 1.53 and 220.5 GPa when diamine ratio of PABZ/ODA was 7/3, which were almost three times and 30 times over that of the PMDA/ODA PI fibers. TGA showed that the PI fibers were thermally stable with 10% weight losses recorded in the range of 492–564°C under nitrogen atmosphere, and their glass transition temperature (Tg) were found to be 410–440°C by DMA with increasing PABZ content from 30 to 70%. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Effect of hot‐press on electrospun poly(vinylidene fluoride) membranes
Authors: Na Haining , Zhao Yuping , Zhao Chenguang , Zhao Ci , Yuan Xiaoyan
Published: March 2008

Poly(vinylidene fluoride) (PVDF) was electrospun into ultrafine fibrous membranes from its solutions in a mixture of N,N‐dimethylformamide and acetone (9:1, v/v). The electrospun membranes were subsequently treated by continuous hot‐press at elevated temperatures up to 155°C. Changes of morphology, crystallinity, porosity, liquid absorption, and mechanical properties of the membranes after hot‐press were investigated. Results of scanning electron microscopy showed that there were no significant changes in fibrous membrane morphology when the hot‐press temperature varied from room temperature to 130°C, but larger pores were formed because of fibers melting and bonding under higher temperatures. Analyses of X‐ray diffraction and differential scanning calorimeter exhibited that the crystalline form of PVDF could transfer from β‐type to α‐type during hot‐press at temperatures higher than 65°C. Tensile tests suggested that the mechanical properties of the electrospun PVDF membranes were remarkably enhanced from 25 to 130°C, whereas the porosity and the liquid absorption decreased. The hot‐press at 130°C was optimal for the electrospun PVDF membranes. The continuous hot‐press post‐treatment could be a feasible method to produce electrospun membranes, not limited to PVDF, with suitable mechanical properties as well as good porosity and liquid absorption for their applications in high‐quality filtrations or battery separators. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
A method for measuring two‐dimensional refractive index distribution by using Fresnel equations and phase‐shifting interferometry
Authors: Hsieh H. C. , Jian Z. C. , Chen Y. L. , Hsieh P. J. , Su D. C.
Published: March 2008

Based on Fresnel equations and the phase‐shifting interferometry, an alternative method for measuring the two‐dimensional refractive index distribution of a material is presented. A linearly polarized light passes through a quarter wave‐plate and is incident on the tested material. The reflected light propagates through an analyzer, and then the interference signal can be obtained. The special equations to estimate the phase of the interferometric signal can be derived by using Fresnel equations. Next, the associated two‐dimensional phase distribution is measured by the four‐step phase‐shifting interferometry. Then, the measured data are substituted into the special equations derived previously, and the two‐dimensional refractive index distribution of the tested material can be obtained. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ellipsometric studies of opal crystals
Authors: Reza A. , Tamasevicius R. , Babonas J. , Balevicius Z. , Vaicikauskas V. , Golubev V. , Kurdyukov D.
Published: March 2008

Spectroscopic ellipsometry investigations have been performed on synthetic opal crystals containing SiO2 spheres having a diameter of D ∼250 nm. The optical features in the spectra of ellipsometric parameters Ψ and Δ were observed in the region of stop band (500‐550 nm). The ellipsometric spectra were separated due to diffraction and specular reflection. The data were interpreted by using effective homogeneous and stacked multi‐layer media models. The average index of refraction of the opal photonic crystal was estimated in the first model and the angle‐resolved spectra were qualitatively described by the second model. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A spectroscopic ellipsometry investigation of RF‐sputtered crystalline vanadium pentoxide thin films
Authors: Oukassi S. , Gagnard X. , Salot R. , Zahorski D. , Stehlé J. L. , Piel J. P. , Pereira‐Ramos J. P.
Published: March 2008

Vanadium pentoxide (V2O5) raised much interest, in several fields, especially relating to thin film lithium microbatteries. Yet, literature mentioned different results about a variation of electrochemical performance of these films with thickness. The present work is focused on the use of spectroscopic ellipsometry on V2O5 crystalline thin film during growth. Optical properties were determined in the near‐IR‐visible range (0.25‐2 µm). Effective media approximation based model was developed and was used to determine the optical constants of thin films. Thickness and roughness obtained corresponded well to respectively SEM and AFM results. Based on optical refractive index evolution, a density gradient was identified through the film thickness. These results could explain in parts the thickness influence on the electrochemical performance of V2O5 thin films. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ellipsometry study of ultra thin layers of evaporated gold
Authors: Nabok Alexei , Tsargorodskaya Anna , Suryajaya
Published: March 2008

Optical properties of ultra thin (from 1 to 40 nm) films of gold evaporated on glass and silicon were studied with the method of spectroscopic ellipsometry in both external and internal reflection configurations as well as with the UV‐visible absorption spectroscopy. The results obtained showed a gradual shift of the plasmon peak from 580 nm for 1 nm thick films to more than 1000 nm for thick (40 nm) gold films. Such phenomenon can be interpreted in terms of quantum confinement of surface plasmons in gold islands. The threshold of the metal‐dielectric transition was found at the film thickness between 4 and 5 nm. Thiolation of the surface of glass has resulted in a slight decrease in the effective thickness of gold layer and respective smaller blue shift of n (λ) and k (λ) dispersion curves, however no dramatic changes were observed in the film morphology. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Polarimetric imaging for the diagnosis of cervical cancer
Authors: Anastasiadou M. , Martino A. De , Clement D. , Liège F. , Laude‐Boulesteix B. , Quang N. , Dreyfuss J. , Huynh B. , Nazac A. , Schwartz L. , Cohen H.
Published: March 2008

We present a first evaluation of polarimetric imaging in the degree of polarization (DOP) mode for cervical cancer detection. The preliminary results obtained with exvivo biopsies justified the development of a DOP imaging system adapted to commercial colposcope, for invivo studies. A clinical trial of this device is underway in order to compare this imaging modality with classical colposcopy for the visualisation of cervical precancerous or cancerous lesions. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Real‐time ellipsometric study of Ge+ ion implanted SiO2 layers during fast annealing
Authors: Shvets V. A. , Tyschenko I. E. , Chikichev S. I. , Prokopiev V. Yu.
Published: March 2008

In situ ellipsometric measurements were performed during fast high temperature annealing of Ge+ ion implanted SiO2 layers. Low temperature (up to 500 °C) evolution of ellipsometric parameters is governed by water evaporation from the sample surface and film pores. In the temperature interval of 500‐650 °C rapid change of ψ and Δ is observed. This may be explained by near interface crystallization of damaged silicon and defect recombination in implanted layer. On further heating (up to 950 °C) agglomeration of initially dispersed Ge atoms into amorphous clusters occurs, which finally crystallize and increase in size with temperature rising to 1150 °C without melting. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ellipsometric studies of diamond like carbon films prepared by PECVD using pulsed DC power supply
Authors: Rai D. K. , Datta Debjit , Gupta Rajeev , Kumar Satyendra
Published: March 2008

Diamonds like carbon (DLC) films were deposited by DC and pulsed DC glow discharge plasma enhanced chemical vapor deposition technique (PECVD). High deposition rates and uniform thin film were obtained using pulsed DC PECVD glow discharge deposition technique. The optical and surface properties of these films were investigated using transmission spectroscopy, spectroscopic Ellipsometry and atomic force microscopy. Fourier transform infrared spectroscopy was employed to examine the compositional properties and sp3/sp2 ratio in our films. Phase modulated Spectroscopic Ellipsometry (SE) in wide range of 300‐1650 nm was used to determine the complex refractive index (ñ (λ) = n (λ) +ik (λ)) using Forouhi‐Bloomer amorphous model in the analyses of SE data. The extracted parameters are reported. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Temperature dependent reflection anisotropy spectroscopy investigations of vanadyl phthalocyanine films
Authors: Fronk Michael , Bräuer Björn , Zahn Dietrich , Salvan Georgeta
Published: March 2008

The optical anisotropy of VOPc films is investigated in the temperature range from 300 K to 10 K by reflection anisotropy spectroscopy in the energy range from 1.5 eV to 5.5 eV. With changing temperature all spectral features show reversible changes in their relative intensity. The most pronounced changes are observed in the sub‐structure of the Q band related feature when cooling down from 300 K to 100 K indicating a reversible structural modification of the films assisted by the illumination. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Non‐collimated beam ellipsometry
Authors: Juhász G. , Horváth Z. , Major C. , Petrik P. , Polgár O. , Fried M.
Published: March 2008

A new method of polarization reflectometry for mapping purposes is presented. Two different optical arrangements were built to study the specific features of the new technique that uses non‐collimated illumination giving multiple‐angle‐of‐incidence information from rapid measurements of the whole area. The prototypes were built in the form of wide‐angle 3‐wavelength ellipsometers using film polarizers. Using pin‐hole‐CCD‐matrix detector arrangement, the detection is almost background free. It can provide real‐time polarization state parameter maps (and thicknesses and/or refractive index maps) over a relatively large area of the surface with 0.5‐1 mm lateral resolution. The speed of the measuring system makes it suitable for use even on production lines. The accuracy of the device is not higher than that of standard ellipsometers, but it is enough for determining the thickness of the silicon‐dioxide film with subnanometer and the angle‐of‐incidence with subtenthdegree precision. We used the prototype for mapping purposes in the case of homogeneity check of ion implantation in silicon, thickness and porosity mapping on electrochemically etched porous silicon layers, thickness mapping on a polysilicon/silicondioxide layer structure. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ion implantation induced disorder in single‐crystal and sputter‐deposited polycrystalline CdTe characterized by ellipsometry and backscattering spectrometry
Authors: Petrik P. , Khánh N. Q. , Li Jian , Chen Jie , Collins R. W. , Fried M. , Radnóczi G. Z. , Lohner T. , Gyulai J.
Published: March 2008

Bulk single‐crystal CdTe, sputter‐deposited polycrystalline CdTe films of about 2.5 micron thickness, and single‐crystal Si (c‐Si) have been ion implanted using 350 keV Xe at fluences ranging from 1×1013 to 16×1013 cm–2 so as to create disorder in a controlled way from fully single‐crystalline to fully amorphous material. The general purpose of the investigations is to seek a parameterization of the critical point structures and establish a database for fitting the optical properties of CdTe films having different unknown grain sizes whereby the grain size will be described in terms of an effective defect density. The polycrystalline CdTe samples were magnetron sputtered onto c‐Si followed by CdCl2 and Br2‐methanol treatment to improve properties in terms of grain size and surface smoothness, respectively. The fluences for use in the ion implantation of CdTe were estimated using the SRIM (Stopping and Range of Ions in Matter) software, and cross‐checked by simultaneous implantation of bulk c‐Si samples. The optical properties were characterized by second derivative analysis and by a generalized critical point model. Although the damage created by 350 keV Xe in the simultaneously implanted c‐Si samples, as measured by both spectroscopic ellipsometry and Rutherford backscattering/ channeling spectrometry (RBS/C), agrees well with the expectations based on the SRIM simulation, the damage created in CdTe remains at a very low level even for doses several times higher than the amorphization level estimated by simulation. The character of the dechanneling of the RBS/C spectra indicates extended defects (presumably dislocation loops). This effect was similar in both single‐crystal and thin film polycrystalline CdTe, although less pronounced in thin film samples. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Application of ellipsometry in immersion lithography
Authors: Jeong H. , Cheon H. , Kyoung J. , Oh H. , An* I.
Published: March 2008

Optical lithography with an ArF excimer laser (193 nm) can produce sub 100nm patterns. Without the reduction of wavelength, further increase in resolution is expected by employing an immersion technique in which a liquid medium is filled between the objective lens and underlying photoresist. In this case, resolution can be enhanced through the increase of numerical aperture. However, in order for immersion lithography to be successful, many problems associated with the liquid environment need to be solved. One of the serious problems is the interaction between liquid and photoresist. Liquid may penetrate into the photoresist and cause leaching problem. This in turn modifies the physical and chemical properties of the photoresist. Thus, it is important to monitor the modification of the photoresist by immersion liquid. In this work, spectroscopic ellipsometry and imaging ellipsometry are used to investigate the absorption of liquid by photoresist as well as top coat which is used to prevent water penetration into underlying photoresist. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Investigations of deep lying wide bandgap GaN and InGaN quantum well structures: A challenge for ellipsometric methods
Authors: Rossow U. , Fuhrmann D. , Jönen H. , Hangleiter A.
Published: March 2008

In this contribution we address the problems in characterizing typical group‐III‐nitride QW structures used in LED or laser applications by spectroscopic ellipsometry. Since the buffer layers are transparent in the visible and near UV and the whole layer stack is a few microns thick, the contributions of the nanometer thick QWs to the signal is very small and with ellipsometers with typical resolution in the polarization states hardly to detect. We discuss this in detail for two typical structures – Al‐GaN/GaN and InGaN/GaN – and quantify how the resolution must be improved to overcome this experimental limitation. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical Hall effect studies on modulation‐doped AlxGa1–xAs:Si/GaAs quantum wells
Authors: Hofmann T. , von Middendorff C. , Gottschalch V. , Schubert M.
Published: March 2008

We study the temperature (10 K … 293 K) dependence of the optical Hall effect (OHE) in modulationdoped Alx Ga1–x As:Si / GaAs (x = 0.45) superlattice structures with different quantum well thickness (dGaAs = 16.9 nm and dGaAs = 3.7 nm) using generalized magnetooptic ellipsometry at far‐infrared wavelengths. Free electrons are identified within the wells, but not within the doped barriers. The observed OHE can be fully explained within the Drude model and thermionic rate equations. The quantum‐well free electron density (N = 1.3 × 1017 cm–3) increases five times upon sample cooling within the wells with dGaAs = 3.7 nm, and remains constant within the wells with dGaAs = 16.9 nm. We describe this behavior as a steady state of three quantum well electron condensation processes: Coulombactivation of electron states at the Alx Ga1–x As/GaAs interface, quantum‐well‐barrier reservoir interaction, and irreversible electron emission into the host crystal. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Large enhancement of the thermoelectric Seebeck coefficient for amorphous oxide semiconductor superlattices with extremely thin conductive layers
Authors: Ohta Hiromichi , Huang Rong , Ikuhara Yuichi
Published: March 2008

Herein we demonstrate that amorphous oxide semiconductor (AOS) superlattices composed of a‐In–Zn–O (well) and a‐In–Ga–Zn–O (barrier) layers, fabricated on SiO2 glass substrate by pulsed laser deposition at room temperature, exhibited an enhanced Seebeck coefficient |S |. The |S | value increases drastically with decreasing a‐In–Zn–O thickness (dIZO) when dIZO < ∼5 nm, and reached 73 µV K–1 (dIZO = 0.3 nm), which is ∼4 times larger than that of bulk |S |3D (19 µV K–1), while it kept its high electrical conductivity, clearly demonstrating that the quantum size effect can be utilized in AOS superlattices. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Conservation of polymers: a view to the future
Authors: Abel Marie‐Laure , Coppitters Camille
Published: March 2008

As a further extension of the role of surface analysis in the study of early polymeric conservation artefacts, experiments were conducted to study the morphology and chemistry of fractured thermoplastic beads originating from 1970s jewellery. Two different methods were used to prepare the surfaces, either by breaking the object in compression or using liquid nitrogen to render it brittle.

Scanning electron microscope (SEM) was used to obtain the morphology, whereas x‐ray photoelectron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (ToF‐SIMS) provided the chemistry of the system. The major component of the objects is established as being polystyrene and the presence or absence of certain additives may be observed, particularly at the surface of the bead or at the surface of samples cracked in a vice. The beads exhibit discolouration and cracking. Hexagonal structures of a few micrometers in diameter are also visible if the morphology is examined at high magnification. Such structures are consistent with stress, crazing, photodegradation and exposure of polystyrene to solvents.

Furthermore, it was possible to correlate the presence or absence of additives with the morphologies encountered on the surfaces. Indeed the most damaged samples seemed to be characterised by the absence of additives while exhibiting a composition close to pure polystyrene. Copyright © 2008 John Wiley & Sons, Ltd.
The structure study of amorphous nanocrystalline nanocomposite films of germanium by AFM and EXAFS methods
Authors: Valeev Rishat G. , Deev Andrew N. , Surnin Dmitry V. , Kriventsov Vladimir V. , Karban Oksana V. , Vetoshkin Vladimir M. , Pivovarova Olesya I.
Published: March 2008

The amorphous nanocrystalline semiconductor nanocomposites obtained by evaporation in ultrahigh vacuum at different substrate temperatures show anomalous electro‐physical properties. It may be connected with the structure of clusters which may consist of both crystalline and amorphous phases. The volume portion of the amorphous phase to the nanosized particles can be obtained by the extended x‐ray absorption fine structure (EXAFS) method. In this work we investigate the structure changes of thin nanocomposite films of Ge obtained at condensation temperatures in the range of 25–250 °C by Atomic force microscopy (AFM) and EXAFS methods. Using the method described by Valeev et al. it was shown that the sizes of nanocrystallites in an amorphous matrix vary essentially according to obtaining conditions (according to AFM data); their content vary from 10 to 90%. Copyright © 2008 John Wiley & Sons, Ltd.
Soft X‐ray emission electron microscopy: chemical state microscopy from interface and bulk
Authors: Zimina A. , Batchelor D. R. , Eisebitt S. , Schmeisser D. , Shulakov A. , Eberhardt W.
Published: March 2008

Scanning electron microscopy (SEM) has long been a workhorse of materials science and provides information on morphology, structure and elemental composition. However, information as to the chemical state of the elements is only available for deep lying core levels of the heavy elements and not the light elements. Whilst considerable advances have been made in high‐resolution wavelength dispersive spectroscopy (WDS) and energy dispersive spectroscopy (EDS), electron microscopy in the soft X‐ray region of ≈ 50–1500 eV is lacking. We present first results for a combined instrument of a soft X‐ray emission (SXE) spectrometer together with a spatially resolving (<100 nm) electron gun. Copyright © 2008 John Wiley & Sons, Ltd.
Increased expression of LIGHT/TNFSF14 and its receptors in experimental and clinical heart failure☆
Authors: Dahl Christen Peder , Gullestad Lars , Fevang Børre , Holm Are M. , Landrø Linn , Vinge Leif Erik , Fiane Arnt E. , Sandberg Wiggo J. , Otterdal Kari , Frøland Stig S. , Damås Jan Kristian , Halvorsen Bente , Aukrust Pål , Øie Erik , Yndestad Arne
Published: March 2008

Background:

Clinical and experimental studies suggest a pathogenic role for inflammation in chronic heart failure (HF). LIGHT is a member of the tumour necrosis factor superfamily involved in innate and adaptive immune responses.

Aims:

We sought to investigate a potential pathogenic role of LIGHT in chronic HF.

Methods:

We used various clinical and experimental approaches including studies in post‐infarction HF rats and in vitro studies of endothelial cells and peripheral blood mononuclear cells (PBMC).

Results:

Our main findings were: (i) LIGHT and its receptors (i.e., HVEM and lymphotoxin‐β receptor) were regulated during experimental HF, with strong expression in the infarcted area accompanied by up‐regulation of HVEM in cardiomyocytes and endothelial cells also in the non‐ischaemic part of the left ventricle. (ii) Patients with chronic HF had significantly increased expression of LIGHT on CD3+ T‐cells accompanied by increased expression of HVEM on monocytes and within the failing myocardium. (iii) LIGHT induced interleukin (IL)‐6 expression in endothelial cells. In HF patients, but not in healthy controls, such an IL‐6‐inducing effect was also seen in LIGHT activated PBMC.

Conclusion:

Our findings in both clinical and experimental HF may suggest a role for LIGHT signalling pathways in the progression of chronic HF involving IL‐6‐related mechanisms.
Celecoxib modulates hypertrophic signalling and prevents load‐induced cardiac dysfunction
Authors: Jacobshagen Claudius , Grüber Meike , Teucher Nils , Schmidt Albrecht G. , Unsöld Bernhard W. , Toischer Karl , Nguyen Van Phuc , Maier Lars S. , Kögler Harald , Hasenfuss Gerd
Published: March 2008

In human hearts, the transition from cardiac hypertrophy to advanced heart failure (HF) is accompanied by a tremendous increase in Akt phosphorylation. In non‐myocardial tissue, the cyclooxygenase (COX)‐2 inhibitor celecoxib has been shown to COX‐independently inhibit Akt signalling.

We studied the effects of celecoxib on Akt signalling and hypertrophic response in myocardium. In rabbit isolated cardiac myocytes celecoxib concentration‐dependently (10–100 μmol/L) inhibited the insulin‐induced increase in phosphorylation of Akt and its downstream targets, GSK‐3β and p70 S6 kinase, by reducing the phosphorylation level of the upstream regulator PTEN. Inhibition of Akt signalling was accompanied by a significant suppression of characteristic features of cardiac hypertrophy: Celecoxib concentration‐dependently suppressed the agonist‐induced enhancement of total protein synthesis and BNP mRNA expression.

In mice (C57BL/6NCrl) subjected to left ventricular (LV) pressure overload by aortic banding, celecoxib treatment (50 mg·kg−1·d−1) significantly attenuated LV dilation and contractile dysfunction compared with placebo‐treated mice. Moreover, celecoxib significantly reduced mortality 8 weeks after banding.

Thus, celecoxib can be used to titrate Akt signalling and hypertrophic response in myocardium. It reduces load‐induced LV dilation, contractile dysfunction and mortality in vivo. This may have clinical implications for the prevention and treatment of maladaptive hypertrophy and its progression to HF in humans.
Tissue inhibitor of metalloproteinases levels in patients with chronic heart failure: An independent predictor of mortality
Authors: Frantz S. , Störk S. , Michels K. , Eigenthaler M. , Ertl G. , Bauersachs J. , Angermann C.E.
Published: March 2008

Background:

Matrix metalloproteinases (MMP) and their tissue inhibitors (TIMP) are involved in cardiac remodelling. The prognostic utility of TIMP is unknown in chronic heart failure (CHF).

Aims:

We investigated the association of plasma levels of soluble MMP‐9 and TIMP‐1 with clinical, laboratory and echocardiographic parameters and estimated their prognostic value in the prediction of all‐cause death.

Methods:

MMP‐9, TIMP‐1, tumour necrosis factor‐α, and amino‐terminal pro‐brain natriuretic peptide were measured in 249 consecutively enrolled CHF patients and 74 healthy individuals.

Results:

After adjustment for age, sex and creatinine, levels of TIMP‐1 (1640 vs. 735 ng/ml, P < 0.001) but not MMP‐9 were elevated in CHF patients compared to controls. During a median follow‐up period of 2.5 years, 66 patients (27%) died. In multivariable Cox regression models TIMP‐1 but not MMP‐9 emerged as an independent predictor of all‐cause death (hazard ratio per tertile, 3.5; 95% confidence interval [CI], 2.2–5.1). In addition to the full set of univariately predictive clinical and serological markers, information on TIMP‐1 significantly increased the area under the receiver operating characteristic curve from 0.77 (95% CI, 0.71–0.84) to 0.87 (95% CI, 0.82–0.92).

Conclusion:

In stable CHF patients, TIMP‐1 but not MMP‐9 is of independent and incremental value regarding the prediction of all‐cause death.
Sustained‐release oral morphine versus transdermal fentanyl and oral methadone in cancer pain management
Authors: Mercadante Sebastiano , Porzio Giampiero , Ferrera Patrizia , Fulfaro Fabio , Aielli Federica , Verna Lucilla , Villari Patrizia , Ficorella Corrado , Gebbia Vittorio , Riina Salvatore , Casuccio Alessandra , Mangione Salvatore
Published: March 2008

Purpose: The aim of this study was to compare the analgesic and adverse effects, doses, as well as cost of opioid drugs, supportive drug therapy and other analgesic drugs in patients treated with oral sustained‐release morphine, transdermal fentanyl, and oral methadone.

Patients and methods: One hundred and eight cancer patients, no longer responsive to opioids for moderate pain, were selected to randomly receive initial daily doses of 60mg of oral sustained‐release morphine, 15mg of oral methadone, or 0.6mg (25μg/h) of transdermal fentanyl. Oral morphine was used as breakthrough pain medication during opioid titration. Opioid doses, pain intensity, adverse effects, symptomatic drugs, were recorded at week intervals for 4weeks. Costs of opioid therapy, supportive drugs, and other analgesic drugs were also evaluated.

Results: Seventy patients completed the 4weeks period of study. Five, five, and four patients, treated with oral morphine, transdermal fentanyl, and oral methadone, respectively, required opioid switching. No differences in pain and symptom intensity were observed. Opioid escalation index was significantly lower in patients receiving methadone (p<0.0001), although requiring up and down changes in doses. At the doses used, methadone was significantly less expensive (p<0.0001), while the use and costs of supportive drugs and other analgesics were similar in the three groups. No relevant differences in adverse effects were observed among the groups during either the titration phase and chronic treatment.

Conclusion: All the three opioids used as first‐line therapy were effective, well tolerated, and required similar amounts of symptomatic drugs or co‐analgesics. Methadone was significantly less expensive, but required more changes, up and down, of the doses, suggesting that dose titration of this drug requires major clinical expertise.
Deciphering the assembly pathway of Sm‐class U snRNPs
Authors: Neuenkirchen Nils , Chari Ashwin , Fischer Utz
Published: March 2008

The assembly of the Sm‐class of uridine‐rich small nuclear ribonucleoproteins (U snRNPs), albeit spontaneous in vitro, has recently been shown to be dependent on the aid of a large number of assisting factors in vivo. These factors are organized in two interacting units termed survival motor neuron (SMN)‐ and protein arginine methyltransferase 5 (PRMT5)‐complexes, respectively. While the PRMT5‐complex acts early in the assembly pathway by activating common proteins of U snRNPs, the SMN‐complex functions to join proteins and RNA in a highly ordered, apparently regulated manner. Here, we summarize recent progress in the understanding of this process and discuss the influence exerted by the aforementioned trans‐acting factors.
Max Rubner and the Biopolitics of Rational Nutrition
Authors: Treitel Corinna
Published: March 2008

Eager to move on after the divisiveSonderwegdebates of the 1980s, historians of modern Germany have been busily elaborating a new central narrative around the notion of biopolitics. Aimed at producing a more powerful and productive society by regulating, optimizing, and even exterminating specific human populations, biopolitics has encompassed everything from housing reform, anti-smoking campaigns, and child vaccination programs to pro- and anti-natalist tax policies, national census taking, and the science of industrial hygiene. Identified by Michel Foucault and others as a general feature of all Western modernities, biopolitics has been a particularly fruitful concept for German historians, who have used it to trace the evolution of racial hygiene—the Nazi variant of eugenics and Germany's most infamous application of biopolitical principles—from a politically diverse group of Wilhelmine and Weimar social reformers. The very normality of these reformers, given the international context, has in turn allowed scholars to avoid labeling German modernity as deviant while at the same time framing the murderous dynamic of the Nazi years as a potential latent in modernity more generally. As Edward Ross Dickinson put it in an excellent review article recently, Germany has emerged from this reevaluation “not as a nation having trouble modernizing, but as a nation of troubling modernity.”
Of German Fräuleins, Nazi Werewolves, and Iraqi Insurgents: The American Fascination with Hitler's Last Foray
Authors: von Hodenberg Christina
Published: March 2008

Many aspects of the German-American encounter during the Second World War remain deeply engraved in the American mind. One of them is the story of the German “werewolves,” Hitler's last underground fighters, who challenged the occupying armies in the war's closing months. The werewolf threat made a lasting impression on American troops and media at the time, and on American collective memory up to today. This article traces how the Nazi insurgents became part of an older mythical narrative that continues to infuse not only American popular culture, but even contemporary elite and political discourse. One of the more recent examples is Condoleezza Rice and Donald Rumsfeld's effort to compare the Nazi werewolves with the Iraqi insurgents whose attacks have plagued the occupied country since the American invasion.
The Franco-Prussian Conflict of 1870 and Bismarck's Concept of a “Provoked Defensive War”: A Response to David Wetzel
Authors: Becker Josef
Published: March 2008

In a recent issue ofCentral European History, David Wetzel published a wide-ranging review of the first two volumes of my documentary edition on the Hohenzollern candidacy for the Spanish throne, the immediate pre-history of the Franco-Prussian war of 1870/71. It goes without saying that I read this review by the author ofA Duel of Giants: Bismarck, Napoleon III, and the Origins of the Franco-Prussian War(2001) with particular interest. My first—and lasting—impression is that here was the discussion of a specialist, one that—precisely because of Wetzel's roots in a different historiographical tradition—represents a model of scholarly fairness. In German historiography since the nineteenth century, and primarily for political reasons, comparably fair treatment of works that deal with a central historical figure such as Bismarck has not been the rule. I am no less grateful for the opportunity offered by his critical objections to make some more general and precise points.
Velocity and temperature derivatives in high-Reynolds-number turbulent flows in the atmospheric surface layer. Part 2. Accelerations and related matters
Authors: GULITSKI G. , KHOLMYANSKY M. , KINZELBACH W. , LÜTHI B. , TSINOBER A. , YORISH S.
Published: March 2008

We report the first results of an experiment, in which explicit information on all velocity derivatives (the nine spatial derivatives, ∂ui∂xj, and the three temporal derivatives, ∂ui/∂t) along with the three components of velocity fluctuations at a Reynolds number as high asReλ~104is obtained. No use of the Taylor hypothesis was made, and this allowed us to obtain a variety of results concerning acceleration and its different Eulerian components along with vorticity, strain and other small-scale quantities. The field experiments were performed at five heights between 0.8 and 10m above the ground.

The report consists of three parts. Part 1 is devoted to the description of facilities, methods and some general results. Part 2 concerns accelerations and related matters. Part 3 is devoted to the issues concerning temperature with the emphasis on joint statistics of temperature and velocity derivatives.
Transient and steady state of a rising bubble in a viscoelastic fluid
Authors: PILLAPAKKAM SHRIRAM B. , SINGH PUSHPENDRA , BLACKMORE DENIS , AUBRY NADINE
Published: March 2008

A finite element code based on the level-set method is used to perform direct numerical simulations (DNS) of the transient and steady-state motion of bubbles rising in a viscoelastic liquid modelled by the Oldroyd-B constitutive equation. The role of the governing dimensionless parameters, the capillary number (Ca), the Deborah number (De) and the polymer concentration parameter c, in both the rising speed and the deformation of the bubbles is studied. Simulations show that there exists a critical bubble volume at which there is a sharp increase in the terminal velocity with increasing bubble volume, similar to the behaviour observed in experiments, and that the shape of both the bubble and its wake structure changes fundamentally at that critical volume value. The bubbles with volumes smaller than the critical volume are prolate shaped while those with volumes larger than the critical volume have cusp-like trailing ends. In the latter situation, we show that there is a net force in the upward direction because the surface tension no longer integrates to zero. In addition, the structure of the wake of a bubble with a volume smaller than the critical volume is similar to that of a bubble rising in a Newtonian fluid, whereas the wake structure of a bubble with a volume larger than the critical value is strikingly different. Specifically, in addition to the vortex ring located at the equator of the bubble similar to the one present for a Newtonian fluid, a vortex ring is also present in the wake of a larger bubble, with a circulation of opposite sign, thus corresponding to the formation of a negative wake. This not only coincides with the appearance of a cusp-like trailing end of the rising bubble but also propels the bubble, the direction of the fluid velocity behind the bubble being in the opposite direction to that of the bubble. These DNS results are in agreement with experiments.
Measurements of turbulent crossflow separation created by a curved body of revolution
Authors: GREGORY P. A. , JOUBERT P. N. , CHONG M. S.
Published: March 2008

Using the method pioneered by Gurzhienko (1934), the crossflow separation produced by a body of revolution in a steady turn is examined using a stationary deformed body placed in a wind tunnel. The body of revolution was deformed about a radius equal to three times the body's length. Surface pressure and skin-friction measurements revealed regions of separated flow occurring over the rear of the model. Extensive surface flow visualization showed the presence of separated flow bounded by a separation and reattachment line. This region of separated flow began just beyond the midpoint of the length of the body, which was consistent with the skin-friction data. Extensive turbulence measurements were performed at four cross-sections through the wake including two stations located beyond the length of the model. These measurements revealed the location of the off-body vortex, the levels of turbulent kinetic energy within the shear layer producing the off-body vorticity and the large values of 〈uw〉 stress within the wake. Velocity spectra measurements taken at several points in the wake show evidence of the inertial sublayer. Finally, surface flow topologies and outer-flow topologies are suggested based on the results of the surface flow visualization.