bluuebunny/crossref_metadata_2025_split huggingface dataset:
Endogenous Estrogen Levels and the Effects of Ultra-Low-Dose Transdermal Estradiol Therapy on Bone Turnover and BMD in Postmenopausal Women
Authors: Huang Alison J , Ettinger Bruce , Vittinghoff Eric , Ensrud Kristine E , Johnson Karen C , Cummings Steven R 
Published: July 2007

Abstract
In a randomized controlled trial of a 0.014 mg/d transdermal estradiol patch, serum bone turnover markers decreased to a greater degree in postmenopausal women with lower versus higher endogenous estradiol levels. This suggests that the protective effects of ultra-low-dose estrogen therapy on the postmenopausal skeletal health may depend critically on women's endogenous estrogen levels before treatment.
Introduction: Postmenopausal women with very low or undetectable estradiol levels have lower BMD, increased bone turnover, and increased risk of hip and vertebral fracture. We assessed whether the effects of ultra-low-dose 0.014 mg/d transdermal estradiol (Menostar; Berlex, Montvale, NJ, USA) on bone turnover and BMD are influenced by endogenous estradiol levels.
Materials and Methods: We analyzed data from postmenopausal women (mean age, 66 yr) randomized to an 0.014-mg/d transdermal estradiol patch or placebo in the ultra-low-dose transdermal estrogen (ULTRA) trial. The free estradiol index (FEI), calculated as the ratio of total estradiol (by mass spectometry) to sex hormone-binding globulin (SHBG; by immunoradiometric assay) × 100, was used to estimate bioavailable estradiol at baseline. Among the 382 women who adhered to ≥80% of study medication, we examined change in serum osteocalcin and bone-specific alkaline phosphatase levels at 12 mo and total hip and lumbar spine BMD at 24 mo in each quintile of FEI.
Results: Compared with women in the highest quintile of FEI, those in the lowest quintile of FEI had a 26% greater reduction in bone-specific alkaline phosphatase and 15% greater reduction in osteocalcin in response to ultra-low estradiol treatment (p for trend across quintiles &lt; 0.05). There was a trend toward greater improvement in total hip BMD (p = 0.06) but not spine BMD (p = 0.90) in those with lower versus higher FEI levels.
Conclusions: The beneficial effects of ultra-low-dose 0.014-mg/d transdermal estrogen therapy on skeletal health may depend critically on women's endogenous estrogen levels before treatment.
Surface analysis of groundwood paper treated by diffuse coplanar surface barrier discharge (DCSBD) type atmospheric plasma in air and in nitrogen
Authors: Tóth András , Černáková Ludmila , Černák Mirko , Kunovská Katarína 
Published: July 2007

Abstract
Paper made of groundwood was surface treated by atmospheric plasma of the diffuse coplanar surface barrier discharge (DCSBD) type in air and in nitrogen. Changes in surface composition and chemical bonding of the constituent elements were studied by X-ray photoelectron spectroscopy (XPS), and alterations in wetting were examined by contact angle measurements. Air plasma treatment resulted in strong oxidation but no N incorporation, while the ratio of the area of the O1 component (binding energy 532.1 eV) to that of the O2 component (533.2 eV) decreased, reflecting an increase in the proportion of O in C–O type bonds. Nitrogen plasma treatment followed by exposure to the atmosphere resulted in a slight N incorporation (1.5 at.%) and oxidation even more intense than observed for air plasma treatment. The O1/O2 ratio slightly increased, implying more O in C=O type bonds. The time dependence of surface oxidation showed a local maximum at treatment time of approximately 2 s for both the air and nitrogen plasmas.
Determination of Young's modulus and shear modulus by means of deflection curves for wood beams obtained in static bending tests
Authors: Murata Koji , Kanazawa Tsubasa 
Published: July 2007

Abstract
Young's modulus and shear modulus were simultaneously obtained in a three-point bending test based on Timoshenko's bending theory. Deflection curves of a bent beam were measured by image analysis, and the mechanical properties of the wood were calculated by polynomial regression analysis after excluding the singular region. When beam specimens of spruce (Picea sp.) and mizunara (Quercus crispula) wood were tested, static Young's modulus (E
s) and static shear modulus (G
s) values could be obtained from the deflection curve using finite element analysis. By comparing the dynamic properties (E
d and G
d) obtained by a flexural vibration test, it was estimated that E
s was greater than E
d, while G
s was less than G
d. However, we suppose that the G
s values calculated from the deflection curve are more plausible than those obtained from a conventional bending test.
Studies on fluorescence of cellulosics
Authors: Castellan Alain , Ruggiero Reinaldo , Frollini Elisabete , Ramos Ludmila A. , Chirat Christine 
Published: July 2007

Abstract
Steady-state fluorescence emission spectra of various celluloses were measured at an excitation wavelength of 320 nm. Various spectra recorded in the solid state were compared: (1) ECF bleached papers made of hardwood, the anhydroglucose units of which were chemically modified at C1 and C6 or C2 and C3 positions with carboxylic groups; (2) microcrystalline cellulose; (3) cotton linters; and (4) delignified sisal fibers (mercerized or not). Fluorescence emission was quite independent of the carboxylic acid content and average molecular weight (determined by viscosimetry) of the cellulose polymers. Microcrystalline cellulose (Avicel), cotton linters, and mercerized delignified sisal cellulose were acetylated in homogeneous medium (DMAc/LiCl as solvent system) to obtain soluble polymers in dichloromethane for comparison of spectra recorded in the solid and liquid states. Fluorescence of cellulose acetates in solution (CH2Cl2) and in the solid state was compared under similar experimental conditions to non-esterified celluloses in the solid state. The importance of the solid state for fluorescence emission could be demonstrated. Fluorophores are present in minute amounts in the polymer and their favorable energy transfer for excitation in the solid state likely enhances fluorescence emission. Among numerous fluorophores, dityrosine appeared to be a good candidate for fluorescence because it displayed emission in the fluorescence range of cellulose. Dityrosine is an amino acid involved in the lignification of non-woody plants. Mercerized sisal impregnated with tyrosine in the presence of peroxidase and hydrogen peroxide did not show enhanced emission, in contrast to para-hydroxycinnamic acid (coumaric acid), which is also involved in the lignification process at least for non-woody plants. The origin of cellulose fluorescence remains uncertain and appears to have several origins. This study clearly underlines the importance of the solid state for enhancing fluorophore emission.
Viscoelastic properties of green wood across the grain measured by harmonic tests in the range 0–95°C: Hardwood vs. softwood and normal wood vs. reaction wood
Authors: Placet Vincent , Passard Joëlle , Perré Patrick 
Published: July 2007

Abstract
The viscoelastic properties of wood have been investigated with a dynamic mechanical analyser specifically developed for wooden materials, the WAVET device. Measurements were carried out on four wood species in the temperature range 0–100°C at frequencies varying between 5 mHz and 10 Hz. Wood samples were tested under water-saturated conditions in the radial and tangential directions. As expected, the radial direction always revealed a higher storage modulus than the tangential direction. Great differences were also observed in the loss factor. The tanδ peak and internal friction were higher in the tangential than in the radial direction. This behaviour is attributed to the fact that anatomical elements act as a function of the direction. The viscoelastic behaviour of reaction wood differs from that of normal or opposite wood. Compression wood of spruce, which has a higher lignin content, is denser and stiffer in transverse directions than normal wood, and has a lower softening temperature (T
g). In tension wood, the G-layer is weakly attached to the rest of the wall layers. This may explain why the storage modulus and softening temperature of tension wood are lower than those for opposite wood. We also demonstrate that the time-temperature equivalence fits only around the transition region, i.e., between T
g and T
g+30°C. Apart from these regions, the response of wood reflects the combined effects of all its constitutive polymers, so that the equivalence is no longer valid.
Antwort auf die Fragen von A.M. Ritter nebst einigen weiteren Anmerkungen
Authors: Thümmel Hans Georg 
Published: July 2007

Abstract
In response to A.M. Ritter the infl uence of the Byzantine emperor upon the church is stressed: It is the emperor who appoints and dismisses the patriarchs, convokes synods and takes responsibility even for dogmatic decisions. In the later time, pentarchy, however, is nothing but an idea. Against Ohme a immediate reception of the Seventh Ecumenical Council in the Latin West should be doubted, for nearly 700 years the council was quite unknown to the West. Finally, we should take into account that the proceeding of the councils are rather different as nowadays – and, of course, this should be assumed even for the use of testimonies of the fathers.
The Greek and Jewish Origins of Docetism: A New Proposal
Authors: Goldstein Ronnie , Stroumsa Guy G 
Published: July 2007

Abstract
Despite the amount of work on Docetic trends in early Christianity, in particular in the last generations, thanks to the renewed interest in Gnosticism after the Nag Hammadi discovery, the origins of Docetism remain obscure. While various suggestions have been offered, they usually point to either to Jewish or to Greek origins of Docetic attitudes. This article offers a new model, which seeks to combine both Greek and Jewish origins. The article calls attention to the Greek conception of the eidōlon of a person (or of a divinity) taking its place under certain conditions. This conception had been systematically used in Greek classical literature in order to solve hermeneutical problems in mythology. We argue that the Greek conception of the eidōlon was combined to Jewish interpretations of Genesis 22 and of Psalm 2 in the earliest stages of Christianity in order to offer a solution to the scandal of Christ's Passion.
Bardaisan of Edessa: Philosopher or Theologian?
Authors: Possekel Ute 
Published: July 2007

Zusammenfassung
Bereits im vierten Jahrhundert wurde Bardaisan von Ephräm dem Syrer als „der aramäische Philosoph“ gekennzeichnet, ein Urteil, dem sich auch moderne Forscher angeschlossen haben. Dieser Aufsatz wirft die Frage auf, ob eine solche Charakterisierung angemessen sei. Die Autorin zeigt anhand ausgewählter Beispiele (Ausbildung und Selbstverständnis, Lehre von der Auferstehung der Seele, Ethik und Eigenart von Bardaisan, Schule als Kommunität), daß Bardaisan sich selbst als Theologe und Christ verstanden hat und daß er – wie etliche seiner christlichen Zeitgenossen – versuchte, seinen Glauben auf intellektuell akzeptable Weise darzustellen. Dabei griff Bardaisan zwar auf philosophische Denkkategorien zurück, doch war sein Bemühen in erster Linie ein theologisches.
A Note on Tatian's Diatessaron, Luke, and the Arabic Harmony
Authors: Cook John Granger 
Published: July 2007

Zusammenfassung
Die Frage, ob für die Rekonstruktion von Tatians Diatessaron die sog. Arabische Harmonie benutzt werden kann, ist umstritten. Zugleich ist die Annahme verbreitet, daß die Reihenfolge der Arabischen Harmonie mit der Östlichen Harmonie weitgehend übereinstimmt. Das Lukasevangelium bietet das Material für den Erzählfluß der Arabischen Harmonie, gerade am Anfang und am Ende. Am Anfang und am Ende scheint auch das Johannesevangelium eine wesentliche Rolle zu spielen. Dieses Ergebnis stellt die weitverbreitete Annahme in Frage, daß das Matthäusevangelium die gesamte Harmonie Tatians geprägt hat.
Signal separation theory using adaptive arrays
Authors: Li Qihu 
Published: July 2007

AbstractThe signal separation technique using adaptive arrays is a new area in array data processing. The model considered in this paper is that of an array consisting of N elements; the number of signal sources, which are separated in spatial location, is M and M ≥ N. In the case of narrow band signals, the pre‐envelope form of the incident signal can be obtained from the original signal and its Hilbert transform. The directional bearing‐angle matix G is formed in terms of the conventional beam‐forming system. By using a special implementation, the inverse matrix of G is derived. Finally, a matrix transform is operated on the received signal so that the output signal is separable, i.e. each output channel has only one incident signal. In the case of wide band signals, the DFT of the input signal or heterodyne is required. The block diagrams of the signal separation technique are given and some important results of this technique are derived. The results of system simulation experiments in digital computers prove that this theory is effective for separating signals.
Effect of the choice of error equation on the robustness properties of adaptive control systems
Authors: Bodson Marc 
Published: July 2007

AbstractDifferent approaches may often be used to achieve the same adaptive control objective. In this paper we discuss connections between the choice of error equation and the robustness of the adaptive system. We study a single gain example using averaging methods and show that there are significant differences in the robustness properties of schemes obtained with various approaches.
Some recent results in structured robust stability: An overview
Authors: Chapellat Herve , Bhattacharyya S. P. 
Published: July 2007

AbstractSome recent results on robust stability with structured perturbations, using the polynomial framework, are presented in this paper without proof. As background we first describe Kharitonov's theorem and give an interpretation of it as a generalization of the Hermite—Bieler interlacing theorem. The need for a generalization of this result for tackling the control problem is explained, and our new results are then presented. An important generalization of Kharitonov's theorem that solves the box problem in parameter space is described. Some efficient formulae for the l2‐stability margin in parameter space are also given. The results are illustrated by examples.
Dual control of a first‐order system with two possible gains
Authors: Bernhardsson Bo 
Published: July 2007

AbstractThe dual control law for the system y(t + 1) = ay(t) + bu(t) + σe(t + 1) is computed. Here a is supposed to be known. The gain b is unknown but can only take two values, b1 or b2. The Bellman equation is solved numerically. Properties of the dual control law are discussed. By varying a it is studied how probing depends on stability. For small a there is no probing. It is shown that the area of probing is increased as the process becomes more unstable.
Adaptive prediction in the presence of unmodelled dynamics
Authors: Radenković Miloje S. 
Published: July 2007

AbstractThis paper considers the prediction problem for a discrete‐time stochastic system with unmodelled dynamics. The precisely modelled part of the system is described by an ARMAX model, while unmodelled dynamics is represented by a small constant ζ multiplied by a quantity tending to infinity as the past input, output and noise of the system increase. For the estimation of the unknown predictor parameters, the usual stochastic approximation algorithm is used. Under the standard conditions imposed on the modelled system part, it is shown that the mean‐square prediction error converges to a finite limit. This limit depends explicitly on the unmodelled dynamics in such a way that when the unmodelled dynamics decays, the prediction error tends to the minimum possible.
Example applications of the partial state model reference adaptive design technique
Authors: M'saad M. , Landau I. D. , Duque M. , Samaan M. 
Published: July 2007

AbstractThis paper presents an implementation methodology for adaptive control schemes. The latter have been developed bearing in mind the available theoretical results as well as the practical requirements. This leads to an adaptive control software package which can run on several digital computers, including the IBM‐PC and compatibles. Simulation results involving two adaptive control benchmarks are presented.
Application of the robust and adaptive pole placement design technique
Authors: Åström K. J. 
Published: July 2007

AbstractIn this paper the problem is solved using a self‐tuner based in indirect adaptive pole placement. This design approach fits nicely to the specifications given. The design method for the case of known parameters is first presented. The adaptive algorithm is then given. The standard algorithm can cope with the problem and the specified parameter variations. Some special features of the given problem are discussed and several variations are then given. It is also shown that the problem can be solved using a robust fixed‐gain regulator.
Unbiased parameter estimation of linear systems in the presence of input and output noise
Authors: And Wei‐Xing Zheng , Feng Chun‐Bo 
Published: July 2007

AbstractIt is well known that in practical situations the observed input‐output data of an identified plant are usually corrupted by measurement noise. In this case the ordinary least‐squares estimator of the system parameters is biased. In order to obtain a consistent estimator, a new type of modified least‐squares estimation method, which is called the bias‐eliminated least‐squares (BELS) method, is presented in this paper. It is shown that the estimation bias can be determined if the variance of the white measurement noise can be obtained accurately. A designed first‐order prefilter is connected in parallel to the input of the identified system. Based on asymptotic analysis, the noise variance can be estimated correctly by using the processed sampled data. Both a batch algorithm and a recursive algorithm are presented. It is shown that the presented BELS method gives a consistent estimate without a priori knowledge of the variance of the white input and output noise. Simulation results are presented to support the theoretical discussions.
A stochastic embedding approach for quantifying uncertainty in the estimation of restricted complexity models
Authors: Goodwin Graham C. , Salgado Mario E. 
Published: July 2007

AbstractThis paper presents a new approach to the understanding and treatment of the effects of undermodelling in the estimation of models for dynamical systems. There already exists a substantial body of knowledge dealing with the implications of undermodelling on robust control system design. However, the corresponding problem for model estimation has received only scant attention. This paper presents a general conceptual and philosophical framework which adds the important dimension of undermodelling to the estimation problem. The philosophy of the approach is to embed the nominal model structure into a larger class of models which includes a generic characterization of undermodelling. This broader perspective allows the effects of limited model complexity on estimation to be quantified.The implications of these results are believed to be wide‐ranging and include new insights into the role of user choices and experimental conditions in estimation, integration of robust and adaptive control, new strategies for fault detection and diagnosis, and so on.
Black‐box identification of mimo transfer functions: Asymptotic properties of prediction error models
Authors: Zhu Yu‐Cal 
Published: July 2007

AbstractIdentification of multi‐input/multi‐output (MIMO) transfer functions is considered. The transfer function matrix is parametrized as black‐box models which have certain shift properties; no structure or order is chosen a priori. In order to obtain a good transfer function estimate, we allow the order of the model to increase to infinity as the number of data tends to infinity. The expression of asymptotic covariance of the transfer function estimates is derived, which is asymptotic both in the number of data and in the model order. The result indicates that the joint covariance matrix of the transfer function estimates of the process and of the noise filter is proportional to the (generalized) ratio of output noise to imput signal; the factor of proportionality is the ratio of model order to number of data. The result is independent of the particular model structure used. This result is the MIMO extension of the theory of Ljung. The application of this theory for defining the upper bounds of identification errors is highlighted.
Decentralized stochastic adaptive control of interconnected systems
Authors: Radenkovic Miloje S. 
Published: July 2007

AbstractThis paper considers the stochastic adaptive control problem for a class of large‐scale systems formed by arbitrary interconnection of subsystems with unknown parameters and non‐linearities. For the estimation of the unknown parameters of the local controllers, stochastic approximation algorithms are used. Conditions sufficient for global stability of the overall system are established. It is shown that the overall tracking error is bounded by a quantity depending on the size of interconnections.
An adaptive non‐linear estimate for radar target tracking
Authors: Hsiao C. H. , Chuang K. C. 
Published: July 2007

AbstractThe detection of targets with a radar system is inherently a non‐linear stochastic process. Thus the application of non‐linear estimation becomes inevitable. A review of four approaches—the extended Kalman filter (EKF), the Gaussian second‐order filter (GSF), the iterative filter (IF) and the adaptive filter (AF)—is given in this paper. The superiority of AF in tracking manoeuvring targets is quite clear in comparison with the other filters.
Identification/prediction algorithms for armax models with relaxed positive real conditions
Authors: Moore J. B. , Niedzwiecki M. , Xia Lige 
Published: July 2007

AbstractExtended least squares (ELS) algorithms are proposed for ARMAX model identification with the objective of avoiding the positive real condition associated with standard equation error and output error algorithms. This is achieved by an overparametrization at the cost of additional richness requirements on excitation signals, but without introducing ill‐conditioning or infinite‐dimensional calculations as in earlier methods. Results for the case of D‐step‐ahead prediction ELS algorithms for ARMAX models are also explored in the paper. Some simulation studies are included to assess the relative performance characteristics of the proposed algorithms, and the nature of the relaxed positive real condition for different degrees of overparametrization N is investigated in detail for second‐order noise models.