bluuebunny/crossref_metadata_2025 huggingface dataset:
Noisy and chaotic conditions of a pendulum motion
Authors: Borowiec Marek , Litak Grzegorz
Published: March 2010

The effect of noise on the rotational mode of a pendulum which is excited kinematically in vertical direction has been analyzed. We have applied the multifractal analysis to distinguish chaotic and noisy solutions in transitions from the oscillations to rotations motion of a pendulum. During increasing the noisy disturbance of the system we analyzed the basic multifractals criteria of the system as correlation and complexity. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
ℋ∞ Control for Descriptor Systems – a Pencil Based Approach
Authors: Benner Peter , Losse Philip
Published: March 2010

The ℋ∞ control problem is studied for linear constant coefficient descriptor systems. Necessary and sufficient optimality conditions as well as controller formulas are derived in terms of deflating subspaces of even matrix pencils for index one systems as well as for higher index problems. A structure preserving method for computing these subspaces is introduced. In combination these results allow the derivation of a numerical algorithm with advantages over the classsical methods. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Extremal Extensions of the Tensor Product of Nonnegative Operators
Authors: Nafalska Maria Magdalena
Published: March 2010

For densely defined nonnegative operators A and B acting in separable Hilbert spaces we describe the Friedrichs and the Krein‐von Neumann extension of the tensor product $A \hat\otimes B$. Moreover, we discuss the class of extremal extensions of $A \hat\otimes B$. An application is presented as well. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analytic Operator Functions with Selfadjoint Coefficients
Authors: Förster Karl‐Heinz , Hartanto Niels
Published: March 2010

In this note, results of H. K. Wimmer [2] are extended to functions with values in the space of bounded linear operators $B(\cal{H})$ in the Hilbert space \cal{H}$, which are analytic on an annulus and have selfadjoint coefficients. The eigenvalues on the boundary of the spectrum of the functions considered in this note, corresponding to a fixed eigenvector possess a certain symmetry which is well known from the periphal spectrum of entrywise nonnegative matrices, due to the Perron‐Frobenius theorem. Similar results hold for polynomials of type (1) with entrywise nonnegative matrix coefficients Aj, see [1]. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the nonreal eigenvalues of elliptic differential operators with indefinite weights on Lipschitz domains
Authors: Behrndt Jussi , Sète Olivier
Published: March 2010

The nonreal spectrum of a second order elliptic differential operator with an indefinite weight function on a Lipschitz domain is investigated with the help of Krein space techniques and perturbation methods. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Port‐based approach to distributed transfer function method
Authors: Orlikowski C. , Hein R. , Wittbrodt E.
Published: March 2010

In the paper there is presented an uniform, port‐based approach to modeling of both lumped and distributed parameter systems. Port‐based model of distributed system has been defined by application of distributed transfer function method (DTFM). The approach proposed combines versatility of port – based modeling and accuracy of distributed transfer function method. It enables to formulate appropriate input data for computer analysis by application of DTFM. The concise representation of lumped‐distributed systems is obtained. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Diagnostics‐based Approach to Vibration Surveillance during High Speed Milling of Flexible Details
Authors: Kaliński Krzysztof
Published: March 2010

The paper concerns vibration surveillance during ball end milling of curved flexible details and considering assurance of parameters of a modal subsystem. Here is explained dynamic analysis of non‐stationary vibrating system, from which are separated subsystems: modal, structural and connective. Minimising vibration level by matching the spindle speed to optimal phase shift has been employed. Two alternatives of the approach have been developed. The first one is based on generalised condition of optimum spindle speed and relates to diagnosis of chatter vibration with only one detected frequency. The second approach concerns a few harmonic components having different frequencies. Obtained results of production experiments proved a meaning of the approaches. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vibro‐acoustic method for estimating a liquid level and viscosity
Authors: Szparaga Lukasz , Tarnowski Wojciech , Plawgo Agnieszka , Bartosik Przemyslaw
Published: March 2010

The goal of this work has been to examine a possibility to measure a liquid level and its viscosity by the vibro‐acoustic methods. Preliminary laboratory investigations were completed on a glass vessel filled with solutions of various viscosity and level, excited by a hammer. A microphone and four accelerometers were used as sensors. Few criteria symptoms were checked. For the level and viscosity estimation there were used the placement and values of the Fourier's spectra maximum of the acoustic signal, and of the vibration signals from sensors. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Economically study regarding modernizing of the final working of the car radiators through implementation of an articulated robot in a flexible manufacturing cell
Authors: Simion Mihaela , Petrişor Silviu Mihai
Published: March 2010

In this paper the authors purpose the conception and modelling of a possible application in a circular flexible manufacturing cell. This flexible cell is composed from five manufacturing points for realizing the final technological itinerary of a type of radiator. This flexible manufacturing cell is served by an industrial articulated robot, which possess in his cinematic chain three degrees of freedom, type RRT. In virtue of real values of the functional parameters which are input data in the analysis of the flexible manufacturing cell, had been dignify the cost of the flexible manufacturing cell, determining the value of the included industrial robot in the system and the value of the entire flexible cell where the robot realize the manipulating process of the radiators. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Material Model for the Lifetime Prediction of Regeneratively Cooled Nozzle Structures
Authors: Tini Vivian , Reese Stefanie
Published: March 2010

Regeneratively cooled nozzle structures of a Reusable Launch Vehicle (RLV) belong to the most critical components of a space shuttle main engine. The severe operating conditions have been experimentally observed to cause the so‐called “dog‐house” failure mode. Within the DFG Project to develop new technologies for the future space transportation system, a material model which sufficiently describes this phenomenon is needed. In this project we are using a new continuum mechanical approach motivated by a rheological model. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Response of the mechanical system with the hysteresis in a high frequency limit
Authors: Kasperek Rafał , Litak Grzegorz
Published: March 2010

Vibrations of a single‐degree‐of‐freedom oscillator with a hysteretic damper subjected to kinematic excitations in a high frequency limit have been explored. By using of two time scales expansion we derived an effective damping coefficient. It has been shown that in the limit of the high excitation frequency the hysteretic loop could be eliminated for the slow time scale dynamics. For simplicity, to examine the effect of hysteresis we used the model of a single hysteron. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Reliability based limit design of steel frames with limited residual strain energy capacity
Authors: Rad Majid Movahedi , Lógó János , Knabel Jaroslaw , Tauzowski Piotr
Published: March 2010

The aim of this paper is to take into consideration the influence of the limited load carrying capacity of the connections on the plastic limit state of elasto‐plastic steel (or composite) framed structures under multi‐parameter stochastic loading and probabilistically given conditions. In addition to the plastic limit design to control the plastic behaviour of the structure, bound on the complementary strain energy of the residual forces is also applied. This bound has significant effect for the load parameter. If the design uncertainties (manufacturing, strength, geometrical) are expressed by the calculation of the complementary strain energy of the residual forces a reliability based extended limit design problem is formed. The formulations of the problems yield to nonlinear mathematical programming which are solved by the use of sequential quadratic algorithm. The bi‐level optimization procedure governed by the reliability index calculation. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Isogeometrical approach for cable type structures allowing large sliding contact
Authors: Konyukhov Alexander , Schweizerhof Karl
Published: March 2010

A special combination of two finite elements approaches is considered in order to derive a formulation suitable for cable type structures. First, a finite beam element allowing arbitrarily large rotations together with a high order approximation technique including a C1‐continuous approximation is used to model cable behavior. Afterwards, a covariant approach for a curve‐to‐curve contact is exploited to incorporate contact between a pair of cable elements. This leads to a cable type element with contact. In numerical examples both “soft” and “hard” cables are represented. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On wheel–rail contact problem with material properties varying with depth
Authors: Chudzikiewicz Andrzej , Myśliński Andrzej
Published: March 2010

Numerous laboratory experiments indicate that the use of a layer or a coating material attached to the conventional steel body reduce the magnitude of contact stress. Therefore in this paper we solve numerically the wheel–rail contact problem with friction and wear assuming the existence of a small elastic layer on the rail surface. Material properties of this layer are changing with its depth. The friction between the bodies is governed by Coulomb law. In contact zone Archard's law of wear is assumed. We take special features of this rolling contact problem and use so‐called quasistatic approach to solve this contact problem. Finite element method is used as a discretization method. The numerical results including the distribution of normal stress along the contact boundary are provided and discussed. (© 2009 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparative analysis of soybean plasma membrane proteins under osmotic stress using gel‐based and LC MS/MS‐based proteomics approaches
Authors: Nouri Mohammad‐Zaman , Komatsu Setsuko
Published: March 2010

To study the soybean plasma membrane proteome under osmotic stress, two methods were used: a gel‐based and a LC MS/MS‐based proteomics method. Two‐day‐old seedlings were subjected to 10% PEG for 2 days. Plasma membranes were purified from seedlings using a two‐phase partitioning method and their purity was verified by measuring ATPase activity. Using the gel‐based proteomics, four and eight protein spots were identified as up‐ and downregulated, respectively, whereas in the nanoLC MS/MS approach, 11 and 75 proteins were identified as up‐ and downregulated, respectively, under PEG treatment. Out of osmotic stress responsive proteins, most of the transporter proteins and all proteins with high number of transmembrane helices as well as low‐abundance proteins could be identified by the LC MS/MS‐based method. Three homologues of plasma membrane H+‐ATPase, which are transporter proteins involved in ion efflux, were upregulated under osmotic stress. Gene expression of this protein was increased after 12 h of stress exposure. Among the identified proteins, seven proteins were mutual in two proteomics techniques, in which calnexin was the highly upregulated protein. Accumulation of calnexin in plasma membrane was confirmed by immunoblot analysis. These results suggest that under hyperosmotic conditions, calnexin accumulates in the plasma membrane and ion efflux accelerates by upregulation of plasma membrane H+‐ATPase protein.
Androgen ablation augments human HLA2.1‐restricted T cell responses to PSA self‐antigen in transgenic mice
Authors: Arredouani Mohamed S. , Tseng‐Rogenski Stephanie S. , Hollenbeck Brent K. , Escara‐Wilke June , Leander Karen R. , Defeo‐Jones Deborah , Hwang Clara , Sanda Martin G.
Published: March 2010

BACKGROUND

In recent years, there has been an increasing interest in targeting human prostate tumor‐associated antigens (TAAs) for prostate cancer immunotherapy as an alternative to other therapeutic modalities. However, immunologic tolerance to TAA poses a significant obstacle to effective, TAA‐targeted immunotherapy. We sought to investigate whether androgen deprivation would result in circumventing immune tolerance to prostate TAA by impacting CD8 cell responses.

METHODS

To this end, we generated a transgenic mouse that expresses the human prostate‐specific antigen (PSA) specifically in the prostate, and crossed it to the HLA‐A2.1 transgenic mouse to evaluate how androgen deprivation affects human HLA A2.1‐resticted T cell responses following immunization of PSA‐expressing mice by vaccinia‐PSA (PROSTVAC).

RESULTS

Our PSA transgenic mouse showed restricted expression of PSA in the prostate and detectable circulating PSA levels. Additionally, PSA expression was androgen‐dependent with reduced PSA expression in the prostate within 1 week of castration, and undetectable PSA by day 42 after castration as evaluated by ELISA. Castration of the PSA/A2.1 hybrid mouse prior to immunization with a PSA‐expressing recombinant vaccinia virus resulted in a significant augmentation of PSA‐specific cytotoxic lymphocytes.

CONCLUSIONS

This humanized hybrid mouse model provides a well‐defined system to gain additional insight into the mechanisms of immune tolerance to PSA and to test novel strategies aiming at circumventing immune tolerance to PSA and other TAA for targeted prostate cancer immunotherapy. Prostate © 2010 Wiley‐Liss, Inc.
Physcion, a natural anthraquinone derivative, enhances the gene expression of leaf‐specific thionin of barley against Blumeria graminis
Authors: Ma Xingxia , Yang Xiaojun , Zeng Fansong , Yang Lijun , Yu Dazhao , Ni Hanwen
Published: March 2010

BACKGROUND:

Physcion is a key active ingredient of the ethanol extract from roots of Chinese rhubarb (Rheum officinale Baill.) that has been commercialised in China for controlling powdery mildews. The biological mechanism of action of physcion against the barley powdery mildew pathogen was studied using bioassay and microarray methods.

RESULTS:

Bioassay indicated that physcion did not directly affect conidial germination of Blumeria graminis Speer f. sp. hordei Marchal, but significantly inhibited conidial germination in vivo. Challenge inoculation indicated that physcion induced localised resistance rather than systemic resistance against powdery mildew. Gene expression profiling of physcion‐treated barley leaves detected four upregulated and five downregulated genes (ratio ≥ 2.0 and P‐value < 0.05) by using an Affymetrix Barley GeneChip. The five upregulated probe sequences blasted to the same barley leaf‐specific thionin gene, with significant changes varying from 4.26 to 19.91‐fold. All downregulated genes were defence‐related, linked to peroxidase, oxalate oxidase, bsi1 protein and a pathogenesis‐related protein. These changes varied from − 2.34 to − 2.96. Quantitative real‐time PCR data confirmed that physcion enhanced the gene expression of leaf‐specific thionin of barley.

CONCLUSION:

Results indicated that physcion controls powdery mildew mainly through changing the expression of defence‐related genes, and especially enhancing expression of leaf‐specific thionin in barley leaves. Copyright © 2010 Society of Chemical Industry
Exploring strongly correlated quantum many‐body systems with ultracold atoms in optical lattices
Authors: Bloch Immanuel , Rosch Achim
Published: March 2010

Ultracold quantum gases in optical lattices can be used as novel model system for the exploration of strongly correlated many‐body phases of bosonic or fermionic particles. Here we report on the realization of metallic, Mott‐insulating and band insulating phases in ultracold spin mixtures of fermionic 40K atoms. The experimental results are compared to ab initio dynamical mean field theory (DMFT) calculations.
The effect of laser crystallization on the carrier transport and electroluminescence from nanocrystalline Si/SiO2 multilayers
Authors: Wang T. , Sun H. C. , Liu Y. , Chen G. R. , Xu J. , Wang D. Q. , Wan N. , Li W. , Huang X. F. , Ma Z. Y. , Xu L. , Chen K. J.
Published: March 2010

Periodic amorphous Si (a‐Si)/SiO2 multilayers, fabricated in a conventional plasma enhanced CVD system by alternatively changing the deposition of ultrathin a‐Si film and in‐situ plasma oxidation process, formed (nc‐Si)/SiO2 multilayers after the subsequent KrF laser‐crystallization. Stable electroluminescence (EL) can be achieved at room temperature from laser crystallized multilayers by evaporating ITO and Al as electrodes. The influence of laser energy density on the cur‐ rent‐voltage characteristics and EL property was investigated. It is found that the EL efficiency of laser crystallized sample is changed with laser energy density, and the EL intensity is comparable with that of furnace annealed sample. Our results indicate that the laser crystallization may be an appropriate approach to obtain light‐emitting nanocrystalline Si for future applications. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A microscopic bonding model for the compositional dependence of the first sharp diffraction peak (FSDP) in GexSe1‐xalloys
Authors: Lucovsky Gerald , Phillips James C.
Published: March 2010

This article analyzes results from two papers that have studied the first sharp diffraction peak, FSDP, in GexSe1‐x alloys as a function of the alloy composition, x. The research reported in one of these papers obtained the FSDP in eighteen closely spaced compositions for x between 0.15 and 0.4, and included the intermediate phase, IP, regime between x = ∼0.2 and ∼0.25. S(Q) structure factor plots from diffraction measurements were characterized empirically in terms with several different fitting functions. These second paper used Monte‐Carlo methods for a smaller set of compositions. In this paper, the positions and widths of the FSDP's peaks as a function of alloy composition are correlated with changes in the atomic bonding from Se‐rich to Ge‐rich regimes. Additionally this paper identifies medium range order, MRO, length scales for chemical bonding self‐organizations within the IP regime that are important for promoting macroscopic strain reduction. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dimensional constraints and percolation theory: physical mechanisms controlling electronic structure and defects in high‐k transition metal oxide dielectrics
Authors: Lucovsky Gerald
Published: March 2010

This article addresses three different aspects of nano‐scale structure that are important for the implementation of high‐k gate dielectrics, such as HfO2 and Hf Si oxynitride alloys, for advanced gate stack applications ultra large scale integrated (ULSI) circuit and system chips. Two of these deal with nano‐crystalline thin films where it is necessary to make a distinction between the primitive unit cell, and a more extended electronic cell that can support cooperative Jahn‐Teller distortions. The final example relates the bonding coordination of group IVB transition metal (TM) atoms, Ti, Zr and Hf in a ternary composition in which the concentration of four‐fold coordinated TM atoms is above a critical percolation threshold. This is critical for strain relief, thereby promoting low densities of electronically‐active defects. X‐ray absorption spectroscopy studies play a significant role in revealing these important aspects of nano‐structure, and are interpreted with in the frame‐work of many‐electron electronic structure theory. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analysis of the forgotten parts of the Ge K edge spectra: life before the EXAFS oscillations
Authors: Lucovsky Gerald , Washington Joseph P. , Miotti Leonardo , Paesler Michael
Published: March 2010

The white line and X‐ray absorption near edge spectros‐copy (XANES) spectral regions of the Ge K edge, ∼11100 to 11112 eV, and between 11112 and 11180 eV and beyond, contain electronic structure information that complements near‐neighbor bonding information in the single‐scattering EXAFS regime. The multiple‐scattering XANES features are not generally addressed in EXAFS studies that are targeted to obtain bonding information. There are systematic changes in the X‐ray photon energy of the spectral peak of the white line for Ge‐Sb‐Te (GST) alloys, GeSb and GeTe model compounds, and other Ge alloys that scale directly with average bond ionicity. The spectral widths of these features correspond tp electronic transitions important in optical memory devices. There are other features in the XANES region associated with shake‐off effects for shallow atomic core states that re‐veal bonding information important in analysis of the oscillatory features in the EXAFS regime. These include bonding pairs that are addressed in the fit procedures; e.g., Ge‐Te and Ge‐Sb in GST 225. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Composition and bonding structure of plasma‐assisted ALD Al2O3 films
Authors: Verlaan V. , van den Elzen L. R. J. G. , Dingemans G. , van de Sanden M. C. M. , Kessels W. M. M.
Published: March 2010

A systematic study on the composition and bonding structure of plasma‐assisted ALD Al2O3 films deposited at substrate temperatures between 25 and 400 °C is presented. The composition of the films is determined with Rutherford back scattering (RBS) and elastic recoil detection (ERD). The O/Al atom ratio in the films changes from 2.0 to 1.5 and the mass density increases from 2.6 to 3.1 g/cm3 when increasing the substrate temperature. The hydrogen content decreases with substrate temperature from 13 at.% at 50 °C to less than 1 at.% at 400 °C. Fourier transform infrared spectroscopy shows that the H atoms are predominantly bonded to O atoms, and that the H atoms are effectively removed after annealing at 400 °C. Depth resolved XPS measurements reveal that the atomic concentrations remains constant after annealing. The O1s and Al2p XPS peak positions show that film has different bonding structure at the interface. compared to the bulk. After annealing the bulk of the film shows indications of relaxation whereas the interface is unchanged. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the conditional logistic estimator in two‐arm experimental studies with non‐compliance and before–after binary outcomes
Authors: Bartolucci Francesco
Published: March 2010

The behavior of the conditional logistic estimator is analyzed under a causal model for two‐arm experimental studies with possible non‐compliance in which the effect of the treatment is measured by a binary response variable. We show that, when non‐compliance may only be observed in the treatment arm, the effect (measured on the logit scale) of the treatment on compliers and that of the control on non‐compliers can be identified and consistently estimated under mild conditions. The same does not happen for the effect of the control on compliers. A simple correction of the conditional logistic estimator is then proposed, which allows us to considerably reduce the bias in estimating this quantity and the causal effect of the treatment over control on compliers. A two‐step estimator results on the basis of which we can also set up a Wald test for the hypothesis of absence of a causal effect of the treatment. The asymptotic properties of the estimator are studied by exploiting the general theory on maximum likelihood estimation of misspecified models. Finite‐sample properties of the estimator and of the related Wald test are studied by simulation. The extension of the approach to the case of missing responses is also outlined. The approach is illustrated by an application to a dataset deriving from a study on the efficacy of a training course on the breast self examination practice. Copyright © 2010 John Wiley & Sons, Ltd.
Proportional hazards models and age–period–cohort analysis of cancer rates
Authors: Rosenberg Philip S. , Anderson William F.
Published: March 2010

Age–period–cohort (APC) analysis is widely used in cancer epidemiology to model trends in cancer rates. We develop methods for comparative APC analysis of two independent cause‐specific hazard rates assuming that an APC model holds for each one. We construct linear hypothesis tests to determine whether the two hazards are absolutely proportional or proportional after stratification by cohort, period, or age. When a given proportional hazards model appears adequate, we derive simple expressions for the relative hazards using identifiable APC parameters. To demonstrate the utility of these new methods, we analyze cancer incidence rates in the United States in blacks versus whites for selected cancers, using data from the National Cancer Institute's Surveillance, Epidemiology, and End Results Program. The examples illustrate that each type of proportionality may be encountered in practice. Published in 2010 by John Wiley & Sons, Ltd.
A weighted combination of pseudo‐likelihood estimators for longitudinal binary data subject to non‐ignorable non‐monotone missingness
Authors: Troxel Andrea B. , Lipsitz Stuart R. , Fitzmaurice Garrett M. , Ibrahim Joseph G. , Sinha Debajyoti , Molenberghs Geert
Published: March 2010

For longitudinal binary data with non‐monotone non‐ignorably missing outcomes over time, a full likelihood approach is complicated algebraically, and with many follow‐up times, maximum likelihood estimation can be computationally prohibitive. As alternatives, two pseudo‐likelihood approaches have been proposed that use minimal parametric assumptions. One formulation requires specification of the marginal distributions of the outcome and missing data mechanism at each time point, but uses an ‘independence working assumption,’ i.e. an assumption that observations are independent over time. Another method avoids having to estimate the missing data mechanism by formulating a ‘protective estimator.’ In simulations, these two estimators can be very inefficient, both for estimating time trends in the first case and for estimating both time‐varying and time‐stationary effects in the second. In this paper, we propose the use of the optimal weighted combination of these two estimators, and in simulations we show that the optimal weighted combination can be much more efficient than either estimator alone. Finally, the proposed method is used to analyze data from two longitudinal clinical trials of HIV‐infected patients. Copyright © 2010 John Wiley & Sons, Ltd.
A comparison of United States and United Kingdom EQ‐5D health states valuations using a nonparametric Bayesian method
Authors: Kharroubi Samer A. , O'Hagan Anthony , Brazier John E.
Published: March 2010

Cost‐effectiveness analysis of alternative medical treatments relies on having a measure of effectiveness, and many regard the quality adjusted life year (QALY) to be the current ‘gold standard.’ In order to compute QALYs, we require a suitable system for describing a person's health state, and a utility measure to value the quality of life associated with each possible state. There are a number of different health state descriptive systems, and we focus here on one known as the EQ‐5D. Data for estimating utilities for different health states have a number of features that mean care is necessary in statistical modelling.

There is interest in the extent to which valuations of health may differ between different countries and cultures, but few studies have compared preference values of health states obtained from different countries. This article applies a nonparametric model to estimate and compare EQ‐5D health state valuation data obtained from two countries using Bayesian methods. The data set is the US and UK EQ‐5D valuation studies where a sample of 42 states defined by the EQ‐5D was valued by representative samples of the general population from each country using the time trade‐off technique. We estimate a utility function across both countries which explicitly accounts for the differences between them, and is estimated using the data from both countries. The article discusses the implications of these results for future applications of the EQ‐5D and for further work in this field. Copyright © 2010 John Wiley & Sons, Ltd.
On Bayesian shared component disease mapping and ecological regression with errors in covariates
Authors: MacNab Ying C.
Published: March 2010

Recent literature on Bayesian disease mapping presents shared component models (SCMs) for joint spatial modeling of two or more diseases with common risk factors. In this study, Bayesian hierarchical formulations of shared component disease mapping and ecological models are explored and developed in the context of ecological regression, taking into consideration errors in covariates. A review of multivariate disease mapping models (MultiVMs) such as the multivariate conditional autoregressive models that are also part of the more recent Bayesian disease mapping literature is presented. Some insights into the connections and distinctions between the SCM and MultiVM procedures are communicated. Important issues surrounding (appropriate) formulation of shared‐ and disease‐specific components, consideration/choice of spatial or non‐spatial random effects priors, and identification of model parameters in SCMs are explored and discussed in the context of spatial and ecological analysis of small area multivariate disease or health outcome rates and associated ecological risk factors. The methods are illustrated through an in‐depth analysis of four‐variate road traffic accident injury (RTAI) data: gender‐specific fatal and non‐fatal RTAI rates in 84 local health areas in British Columbia (Canada). Fully Bayesian inference via Markov chain Monte Carlo simulations is presented. Copyright © 2010 John Wiley & Sons, Ltd.
Transvaginal mesh repair of anterior and posterior vaginal wall prolapse: a clinical and ultrasonographic study
Authors: Velemir L. , Amblard J. , Fatton B. , Savary D. , Jacquetin B.
Published: March 2010

Objectives

To investigate whether ultrasonography coupled with clinical examination can help in understanding the mechanism of recurrence after transvaginal mesh repair of anterior and posterior vaginal wall prolapse.

Methods

Ninety‐one patients who had undergone surgery for anterior and/or posterior vaginal wall prolapse with the Prolift system had a clinical examination and introital/endovaginal two‐dimensional ultrasonography a minimum of 1 year later. The retraction of anterior and posterior meshes was estimated relative to the original length of the mesh by transvaginal palpation. Patients with no, moderate (< 50%) or severe (≥ 50%) mesh retraction were compared. Anterior recurrence of prolapse was defined according to the International Continence Society by a Ba value ≥ −1 and posterior recurrence by a Bp value ≥ −1 (where Ba represents the most distal position of the anterior vaginal wall and Bp the most distal position of the posterior vaginal wall). On ultrasonography, two distances were measured in the midsagittal plane: Distance 1, from the distal margin of the anterior mesh to the bladder neck, and Distance 2, from the distal margin of the posterior mesh to the rectoanal junction.

Results

Seventy‐five anterior and 62 posterior meshes were studied at a mean follow‐up of 17.9 months. Patients with anterior recurrence presented significantly more often with severe anterior mesh retraction compared with patients without anterior recurrence (5/8 vs. 2/67, P < 0.001) and also had an increased Distance 1 (P < 0.001). Patients with posterior recurrence presented significantly more often with severe posterior mesh retraction compared with patients without posterior recurrence (3/4 vs. 3/58, P < 0.01) and also had an increased Distance 2 (P < 0.01).

Conclusions

Recurrence of prolapse after transvaginal mesh repair appears to be associated with severe mesh retraction and loss of mesh support on the distal part of the vaginal walls. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Climate, ecology, and conservation: an editorial essay
Authors: Hannah Lee
Published: March 2010

This article is categorized under:

Climate, Ecology, and Conservation > Observed Ecological Changes
Synthesis, Crystal Structure and Spectroscopic Properties of [2,13‐Bis(1‐naphthalenylmethyl)‐5,16‐dimethyl‐2,6,13,17‐tetraazatricyclo(14,4,01.18,07.12)docosane]copper(II) Diperchlorate Acetonitrile Disolvate
Authors: Choi Jong‐Ha , Clegg William , Nichol Gary S.
Published: March 2010

The N‐functionalized macrocyclic ligand 2,13‐bis(1‐naphthalenylmethyl)‐5,16‐dimethyl‐2,6,13,17‐tetraazatricyclo(14,4,01.18,07.12)docosane (L3) and its copper(II) complex were prepared. The crystal structure of [Cu(L3)](ClO4)2·2CH3CN was determined by single‐crystal X‐ray diffraction at 150 K. The copper atom, which lies on an inversion centre, has a square planar arrangement and the complex adopts a stable trans‐III configuration. The longer distance [2.081(2) Å] for Cu–N(tertiary) compared to 2.030(3) Å for Cu–N(secondary) may be due to the steric effect of the attached naphthalenylmethyl group on the tertiary nitrogen atom. Two perchlorate ions are weakly attached to copper in axial sites and are further connected to the ligand of the cation through NH···O hydrogen bonds [N···O 3.098 Å]. IR and UV/Vis spectroscopic properties are also described.
Zur Kristallchemie der Alkali‐, Erdalkali‐, Selten Erdmetall‐Oxozirconate und Zirconiumoxide
Authors: Müller‐Buschbaum Hanskarl
Published: March 2010

The contribution on oxozirconates gives a view on the crystal chemistry of zirconium compounds with large cations, like alkaline, alkaline‐earth and rare earth elements. This is completed by a short overview of the structure types of ZrO2 synthesized by different methods, temperatures and pressures. The most important observation is the missing reflection of the coordination chemistry of zirconiumoxides into the oxozirconates. Usual coordination numbers of zirconium in zirconiumoxide are CN = 8 and occasionally CN = 9. The described oxozirconates instead show mainly octahedral (CN = 6) coordination (such as Li2ZrO3, K2Zr2O5, Li0.8K0.9(LiMgZr)Zr2O6.5, Li6Zr2O9, K4Zr5O12, K2Li14Zr3O14, Pb0.5Ca0.5ZrO3, Nd2Zr2O7, BaCexZr1–xO3). Exceptions with the coordination number six exhibit trigonal ZrO6‐prisms (K4Zr5O12). This facts result in the observation, that zirconium is a member of the anionic parts of the crystal structures. Lower coordination spheres are enforced by the cations. The larger a cation and the larger its amount in the chemical composition is, the lower the coordination number of zirconium gets. For example: CNZr = 5 (tetragonal pyramid) in K2ZrO3, Cs2ZrO3; CNZr = 4 (tetrahedron) in Cs4ZrO4. Furthermore, Zr4+ can also be found in statistical distribution with ions of the same size, like Li+ and Mg2+. Calculations of the Madelung part of lattice energies of zirconium oxides show unexpected uniform data, independent from shape and size of the coordination polyhedra.
Preoperative Radiochemotherapy in T3 Operable Low Rectal Cancers: A Gold Standard?
Authors: Fucini Claudio , Pucciani Filippo , Elbetti Claudio , Gattai Riccardo , Russo Antonio
Published: March 2010

Background

Preoperative chemoradiation followed by total mesorectal excision (TME) has become a standard treatment of preoperatively staged T3 low rectal cancers in many institutions; however, a direct comparison of generalized preoperative versus selective adjuvant chemoradiation has never been assessed in a clinical practice setting.

Patients

Over a 4‐year period, 80 patients with T3 primary low adenocarcinoma of the rectum, judged operable at preoperative staging, were offered preoperative chemoradiation. Forty‐seven patients (Group I) accepted the neoadjuvant treatment and 33 (Group II) preferred immediate surgery and postoperative chemoradiation if indicated.

Results

Major postoperative complications occurred in 21% of Group I versus in 11% of Group II (p = 0.3) patients. After a mean follow‐up of 92 months, the local recurrence rate was 4 and 9% (p = 0.4), metastasis rate was 30 and 24% (p = 0.5), 5‐year survival probability was 0.79 (95% CI = 0.49–0.92) and 0.82 (95% CI = 0.70–1.00) (log‐rank test, p = 0.6) for Group I and Group II, respectively.

Conclusions

In T3 operable low rectal cancers, selective postoperative radiochemotherapy yielded similar long‐term results regarding recurrence rate and survival as extended preoperative chemoradiation.
Expression of Hepatocyte Growth Factor Activator Inhibitor Type 1 in Human Hepatocellular Carcinoma and Postoperative Outcomes
Authors: Funagayama Mayumi , Kondo Kazuhiro , Chijiiwa Kazuo , Kataoka Hiroaki
Published: March 2010

Background

Hepatocyte growth factor activator inhibitor type 1 (HAI‐1), one of the Kunitz‐type serine protease inhibitors, has an important role in cancer progression through regulation of the activity of hepatocyte growth factor. HAI‐1 is expressed in hepatocellular carcinoma (HCC) to various degrees. Investigation of the relationship between HAI‐1 expression and clinicopathological features of HCC may contribute to improved treatment outcomes for HCC through understanding the mechanism of tumor progression or improvement in the prediction of tumor malignancy.

Methods

The study included 121 HCC patients treated surgically from 1996 to 2005. We performed immunohistological examination for HAI‐1 in resected HCC specimens by use of anti‐human HAI‐1 monoclonal antibody. Clinicopathological features, including postoperative overall survival (OS) and disease‐free survival (DFS) rates, were compared between the immunoreaction positive and negative groups.

Results

The immunoreaction positive group included 38 patients (31%), and the negative group included 83 patients (69%). OS and DFS rates were significantly higher in the HAI‐1 negative group than in the positive group. HAI‐1 positivity related to multiplicity, vascular invasion, and characteristics of advanced tumor stage. In multivariate analysis, expression of HAI‐1 was a significant independent prognostic tumor factor.

Conclusions

Expression of HAI‐1 in HCC cells is associated with poor prognosis for HCC patients. HAI‐1 may be important in HCC progression and may be a new prognostic factor for HCC.
Race, Medicine, and the Science behind BiDil: How ACE-Inhibition Took the Fall for the First Ethnic Drug
Authors: Kaufman Jay S. , Nguyen Thu T. , Cooper Richard S.
Published: March 2010

A substantial biomedical literature has accumulated around the question of racial differences in the response to treatment with angiotensin converting enzyme (ACE) inhibitors for hypertension and congestive heart failure. African-origin populations are often asserted to be “low renin”, and therefore to have blunted response to agents that interfere with the renin-angiotensin system. Although the US Food and Drug Administration (FDA) rejected a combination of hydralazine and isosorbide dinitrate as a general heart failure treatment in 1997, this literature on Black resistance to ACE-inhibition therapy for heart failure was used to argue for a race-specific approval for this drug. Specifically, a paper by Exner and colleagues published in the New England Journal of Medicine in 2001 reported that ACE-inhibition reduced hospitalization for White patients, but not for Black patients. The Exner et al paper was used to argue for conducting a randomized trial in Black patients only, the successful completion of which led to FDA approval of the hydralazine and isosorbide dinitrate combination (known as BiDil) as a race-specific therapy in 2005. We re-analyze the data in the 2001 Exner et al study, and show that it is not well suited for answering the question of differential response by race. Even so, the published analysis ignored important facets of the data in order to arrive at the stated conclusion of a race-specific response. Black subjects were recruited mostly in a few regions, and were medically distinct from white patients in terms of clinical measures such as hypertension, diabetes and prescription drug history. Overall, Black subjects had a high risk of the outcomes, and the effect of treatment varied widely by clinical center or by region. The stated conclusion by Exner et al of a race-specific response to ACE inhibition is therefore suspect, as is the use of this conclusion to support the notion of race-specific therapies, both in the specific case of BiDil and in general.
Don de sperme: le lien entre l’anonymat et le bénévolat
Authors: David G.
Published: March 2010

La France a été le premier pays à introduire une nouvelle politique en matière de don du sperme, fondée sur l’anonymat et le bénévolat. L’objectif était de faire entrer le sperme et, d’une manière plus large, les gamètes dans la catégorie des éléments ou des produits humains qui ne peuvent, d’après la loi et en raison de la dignité de la personne, faire l’objet d’un paiement. On assiste de nos jours à une remise en cause de l’anonymat. Or, si l’on se réfère aux nombreux travaux de sociologie concernant le don, il apparaît que le bénévolat est étroitement lié à l’anonymat, avec une vertu sociale, le renforcement de la solidarité collective par un effet d’altruisme désintéressé. Dissocier anonymat et bénévolat ouvrirait la porte à une logique de marché.
The Male Sling for Post-Radical Prostatectomy Urinary Incontinence: Urethral Compression versus Urethral Relocation or What is Next?
Authors: Zeif Hans-Joerg , Almallah Zaki
Published: March 2010

Male stress urinary incontinence is a common complication after prostatic surgery which can have a devastating effect on a patient's quality of life. Treatment can be difficult. If conservative management fails surgical options are available. The latter include the more recently developed male sling procedures which offer encouraging short- and medium-term efficacy and safety. Male slings offer a less invasive and less expensive treatment option compared to the artificial urinary sphincters and allow spontaneous voiding. Success is associated with careful patient selection with higher success rates seen in lower incontinence degrees. A number of innovative developments, products and techniques have led to the emergence of fundamental differences in the surgical mechanism of correcting sphincteric weakness. Male sling devices appear to be following two entirely different technical principles, i.e. compression of the urethra versus relocation of the urethral bulb. There is little doubt that materials and surgical techniques will continue to evolve and the male sling may increasingly become a treatment option in the management of male stress incontinence. However, further objective evaluation and restricted introduction in specialised units are required.
A Journey of Skills—Theory and Practice of a Multi-Modal Learning Approach to Holmium Laser Prostatectomy
Authors: Kastner Christof , Beard Ralph , Woodhams Simon , Knight Olivia , Vyas Lona , Popert Rick
Published: March 2010

Introduction:

Holmium Laser enucleation of the prostate (HoLEP) is an effective treatment, yet the learning curve is considered difficult. We propose the trimodal approach of Holmium Laser ablation (HoLAP), then ablation with resection (HoLARP) and finally enucleation (HoLEP) during the development of surgical competence.

Methods:

A centre experienced in Holmium Laser (HoL) prostatectomy evaluated ablation techniques in prostates less than 50cc as a training modality. Prospective data were collected and outcomes compared with controls who had HoLEP. Subsequently a HoL prostatectomy service was introduced to a new centre and evaluated prospectively during the initial experience of two surgeons mentored by another trained in the trimodal staged approach.

Results:

Outcomes following HoLAP were comparable to HoLEP in prostate volumes under 50 cm3. The new HoL service was evaluated over 6 months. 70 cases were carried out, 42 HoLAP and 28 HoLEP. Outcomes were compared prospectively with 30 TURPs by another surgeon. A decrease in catheterisation time and hospital stay was noted in the laser group.

Conclusion:

The staged progression from HoLAP, then HOLARP and finally to HOLEP with morcellation appears a safe and reproducible way to introduce HoL prostatectomy into standard urological practice.
The Medical Management of Urolithiasis
Authors: Sayer John A. , Moochhala Shabbir H. , Thomas David J.
Published: March 2010

Urolithiasis is increasing in prevalence and causes substantial morbidity and economic burden. Aside from “acute” stone episodes, urolithiasis should be regarded as a systemic disorder and investigated fully. Practical guidance is given for the medical investigation, diagnosis and treatment of urolithiasis. A single episode of urolithiasis should prompt a review of potential risk factors for recurrent disease and appropriate baseline investigations should be performed. Further biochemical tests may then be directed appropriately and allow individualised advice and treatment to be given to the patient with urolithiasis.
Report of the FIGO Working Group on Sexual Violence/HIV: Guidelines for the management of female survivors of sexual assault
Authors: Jina Ruxana , Jewkes Rachel , Munjanja Stephen P. , Mariscal José David Ortiz , Dartnall Elizabeth , Gebrehiwot Yirgu
Published: March 2010

Objective

To review the evidence and provide guidelines on the management of sexual violence against women, specifically, rape.

Outcomes

Outcomes evaluated include effectiveness of post‐rape care provision.

Evidence

The MEDLINE database was searched for articles published up to December 2008 on the topic of post‐rape care and expert opinion was sought from the Sexual Violence Research Initiative membership. In addition, a search was performed for English‐language protocols on Google. One Spanish language protocol was considered in the development of the guidelines.

Values

The evidence was evaluated by authors and reviewers of the South African Department of Health's sexual assault curriculum, and by members of the FIGO Working Group and recommendations were made according to the guidelines developed by the Canadian Task Force on Preventive Health Care.

Benefits, Harms, and Costs

Implementation of the recommendations in this Guideline should result in more appropriate management of survivors of sexual violence and better physical and psychological outcomes.
The Application of Automation to Significantly Accelerate Polymer Latex Research
Authors: Campbell Neil L. , Weaver Jon
Published: March 2010

Polymer latexes are essential components in a wide range of commercial products and formulations such as, paints, cosmetics, coatings, biotechnology, and functionalized supports. Many difficulties are intrinsic to the implementation of polymer latex research, particularly in the purification of the final latex dispersions and the control and reproducibility of particle size, therefore making high-throughput research in this area especially challenging. In this article, we demonstrate how the investigation of the influential synthesis factors on polymer latex materials properties can be swiftly and reproducibly achieved by the combinational use of experimental design, automated synthesis, and a newly developed high-throughput purification process. Through the implementation of flexible automated platforms, a significant increase in the throughput of this previously manual process was achieved. Reaction models were used to examine the synergistic and antagonistic effects of the latex synthesis parameters, thereby allowing the controlled synthesis of fully characterized libraries of surface–functional polymer latexes to be rapidly produced and screened for a wide range of applications.