bluuebunny/crossref_metadata_2025 huggingface dataset:
Patterns and Outcomes of Polypharmacy and Effect of Potentially Inappropriate Medications in Elderly Patients undergoing Orthopaedic Surgeries: A Retrospective Observational Study
Authors: Yohannan Sara , Johny Serah , Vergis Sara Korula , Mathew Celine Thalappillil
Published: January 2024

Introduction: Prescription of Potentially Inappropriate Medication (PIM) among elderly patients is becoming a global concern. There has been an increase in the number of elderly patients coming for operative procedures, especially in orthopaedic surgery, due to the association of advanced age with chronic musculoskeletal conditions, such as osteoarthritis, and an increased incidence of fragility fractures. Aim: To determine the prevalence of polypharmacy and PIMs among elderly patients undergoing orthopaedic surgery. Materials and Methods: A retrospective observational study was conducted from February 2022 to April 2022 in the Orthopaedic Department of Anaesthesiology, MOSC Medical College, Kolenchery, Ernakulam, Kerala, India. Hospital records of 130 patients aged 65 years and above, who underwent orthopaedic surgeries from January 2016 to December 2021, were included. The prescriptions during the perioperative period were analysed for polypharmacy, defined as the use of five or more drugs. The American Geriatric Society (AGS) 2019 Beers criteria were used to identify PIMs, drug interactions, and drugsyndrome interactions. Chi-square tests were performed on clinically significant variables to assess their effect on hospital stay, with a p-value of <0.05 considered significant. Results: Polypharmacy was highest on postoperative day 1, with 119 patients (91.5%) experiencing it. The study observed a high prevalence of PIMs, with 106 patients (81.53%) affected. The most commonly used PIMs were Pantoprazole, followed by Piroxicam, Regular human Insulin, and Glimepride. A significant association was observed between hospital stay ≥10 days, postoperative Intensive Care Unit (ICU) stay, and preoperative polypharmacy (p-value=0.002). Conclusion: Polypharmacy and PIMs in patients above 65 years of age admitted for surgeries remain major concerns. Further exploration of current pharmacologic practices in the perioperative period and interventions, such as physician education programs regarding PIMs, are needed.
Numerische Simulation der NOx‐Reduktion mittels Propen an edelmetallhaltigen Beschichtungs‐Katalysatoren
Authors: Frank E. , Weisweiler W.
Published: April 2003

No abstracts.
A Hydrogen‐Bonded Supramolecular meso‐Helix
Authors: Blay Gonzalo , Fernández Isabel , Pedro José R. , Ruiz‐García Rafael , Muñoz M. Carmen , Cano Joan , Carrasco Rosa
Published: April 2003

A new one‐dimensional hydrogen‐bonded polymer with a unique meso‐helical structure has been prepared from the spontaneous self‐assembly in the solid‐state of meta‐substituted phenylene dioxamic acid diethyl ester monomers. The helical nature of this molecule and its self‐complementary character, through intermolecular hydrogen bonding between oxamic acid ester functions, are the two main factors responsible for the crystalline aggregation process, as confirmed by both experimental X‐ray crystallographic data and theoretical ab initio calculations. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Pyrenoxy‐Based NCN‐Pincer Palladium(II) Molecular Tweezers: Synthesis, Properties in Solution and Catalysis
Authors: Slagt Martijn Q. , Jastrzebski Johann T. B. H. , Gebbink Robertus J. M. Klein , Ramesdonk Hendrik J. van , Verhoeven Jan W. , Ellis Dianne D. , Spek Anthony L. , Koten Gerard van
Published: April 2003

A highly flexible molecular tweezer, (aqua)(2,6‐bis[(dimethylamino)methyl]‐4‐{3‐[(1‐pyrenyloxy)methyl]‐5‐(trimethylsilyl)benzyloxy}phenyl)palladium(II) tetrafluoroborate (1a), constructed from a para‐hydroxy‐functionalized NCN‐pincer palladium(II) complex {NCN−OH = [2,6‐(Me2NCH2)2C6H2‐4‐OH]}, a pyrenoxy unit and a xylyl spacer, was synthesized. X‐ray analysis of the structure of 1‐[3‐({3,5‐bis[(dimethylamino)methyl]‐4‐(trimethylsilyl)phenyloxy}methyl)‐5bromobenzyloxy]pyrene (10), a precursor ligand of 1a, showed a completely flattened conformation in the solid state, imposed by favorable intramolecular π‐stacking interactions. The molecular structure of 1a in solution proved to be fluxional on the NMR timescale. UV/Vis and (time‐resolved) fluorescence spectroscopy revealed that, in spite of the high flexibility, the catalyst and pyrenoxy units are in close proximity because of cation−π interactions. This was further supported by conformer searches using molecular mechanics (MM2). The binding affinity of picric acid towards the pyrenoxy moiety was studied by 1H NMR titrations, revealing association constants Ka in the order of 101 to 102 M−1. Tweezer 1a shows small rate enhancements in aldol condensations of aromatic aldehydes with methyl isocyanoacetate compared to (aqua)(2,6‐bis[(dimethylamino)methyl]4‐{[3‐(trimethylsilyl)benzyloxy}phenyl)palladium(II) tetrafluoroborate (2), which lacks the pyrenoxy unit. The tweezer was immobilized on a G2‐carbosilane dendrimer, generating the dendritic (aqua)(G2‐carbosilane)palladium complex 1b, showing a decreased catalytic activity compared to 1a. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
A computational study of conformational interconversions in 1,4‐dithiacyclohexane (1,4‐dithiane)
Authors: Freeman Fillmore , Derek Elika
Published: April 2003

Ab initio molecular orbital theory with the 6‐31G(d), 6‐31G(d,p), 6‐31+G(d), 6‐31+G(d,p), 6‐31+G(2d,p), 6‐311G(d), 6‐311G(d,p), and 6‐311+G(2d,p) basis sets and density functional theory (BLYP, B3LYP, B3P86, B3PW91) have been used to locate transition states involved in the conformational interconversions of 1,4‐dithiacyclohexane (1,4‐dithiane) and to calculate the geometry optimized structures, relative energies, enthalpies, entropies, and free energies of the chair and twist conformers. In the chair and 1,4‐twist conformers the CHax and CHeq bond lengths are equal at each carbon, which suggest an absence of stereoelectronic hyperconjugative interactions involving carbon–hydrogen bonds. The 1,4‐boat transition state structure was 9.53 to 10.5 kcal/mol higher in energy than the chair conformer and 4.75 to 5.82 kcal/mol higher in energy than the 1,4‐twist conformer. Intrinsic reaction coordinate (IRC) calculations showed that the 1,4‐boat transition state structure was the energy maximum in the interconversion of the enantiomers of the 1,4‐twist conformer. The energy difference between the chair conformer and the 1,4‐twist conformer was 4.85 kcal/mol and the chair‐1,4‐twist free energy difference (ΔG°c‐t) was 4.93 kcal/mol at 298.15 K. Intrinsic reaction coordinate (IRC) calculations connected the transition state between the chair conformer and the 1,4‐twist conformer. This transition state is 11.7 kcal/mol higher in energy than the chair conformer. The effects of basis sets on the 1,4‐dithiane calculations and the relative energies of saturated and unsaturated six‐membered dithianes and dioxanes are also discussed. © 2003 Wiley Periodicals, Inc. J Comput Chem 24: 909–919, 2003
Synthesis of Chiral Helical Chromophore‐Functionalized Polybinaphthalenes
Authors: Koeckelberghs Guy , Groof Leen De , Sioncke Sonja , Verbiest Thierry , Persoons André , Samyn Celest
Published: April 2003

Chromophore‐functionalized, chiral, helical polybinaphthalenes with acetylene linkage have been prepared by functionalization of precursor polymers. The chromophores are chirally ordered in these materials which, together with the many possibilities for architectural diversification, makes these materials promising candidates for nonlinear optical studies as well as applications thereof.

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Propagation and Termination Rate Coefficients in N‐Vinylcarbazole Free Radical Polymerization Obtained via 440 nm Pulsed Laser and Online 1H NMR Kinetic Experiments
Authors: Yin Ming , Davis Thomas P. , Heuts Johan P. A. , Barner‐Kowollik Christopher
Published: April 2003

Propagation rate coefficients, kp, of N‐vinylcarbazole in solution have been determined via visible light pulsed‐laser polymerization over a wide temperature range (EA = 25.3 ± 5 kJ · mol−1, A = 1.0 × 108 L · mol−1 · s−1). The kp data set was used to deduce (average) termination rate coefficients via 1H NMR spectroscopic kinetic experiments and the corresponding Arrhenius parameters (EA = −8.5 kJ · mol−1 ± 8 kJ · mol−1).

Temperature dependence of the propagation rate coefficient, kp, in the free radical solution polymerization of NVC. The graph shows the data from 355 and 440 nm initiation as well as data previously obtained by Yamamoto et al.5 The three sets of data have been analyzed separately (for details see text).

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Temperature dependence of the propagation rate coefficient, kp, in the free radical solution polymerization of NVC. The graph shows the data from 355 and 440 nm initiation as well as data previously obtained by Yamamoto et al.5 The three sets of data have been analyzed separately (for details see text).
Superconducting nanobridges under magnetic fields
Authors: Rodrigo J. G. , Suderow H. , Vieira S.
Published: April 2003

We report on the study of superconducting nanotips and nanobridges of lead with a Scanning Tunnelling Microscope in tunnel and point contact regimes. We deal with three different structures. A nanotip that remains superconducting under a field of 2 T. For this case we present model calculations of the order parameter, which are in good agreement with the experiments. An asymmetric nanobridge of lead showing a two steps loss of the Andreev excess current due to different heating and dissipation phenomena in each side of the structure. A study of the effect of the thermal fluctuations on the Josephson coupling between the two sides of a superconducting nanobridge submitted to magnetic fields. The different experiments were made under magnetic fields up to twenty five times the volume critical field of lead, and in a temperature range between 0.6 K and 7.2 K.
A linear diagnosis of the coupled extratropical ocean–atmosphere system in the GFDL GCM
Authors: Newman Matthew , Alexander Michael A. , Winkler Christopher R. , Scott James D. , Barsugli Joseph J.
Published: April 2003

Diagnosing a coupled system with linear inverse modelling (LIM) can provide insight into the nature and strength of the coupling. This technique is applied to the cold season output of the GFDL GCM, forced by observed tropical Pacific SSTs and including a slab mixed layer ocean model elsewhere. It is found that extratropical SST anomalies act to enhance atmospheric thermal variability and diminish barotropic variability over the east Pacific in these GCM runs, in agreement with other theoretical and modelling studies. North‐west Atlantic barotropic variability is also enhanced. However, all these feedbacks are very weak. LIM results also suggest that North Pacific extratropical SST anomalies in this model would rapidly decay without atmospheric forcing induced by tropical SST anomalies. Copyright © 2000 Royal Meteorological Society.
EXTRACTION OF HANDWRITTEN DATA FROM NOISY GRAY-LEVEL IMAGES USING A MULTISCALE APPROACH
Authors: CHERIET MOHAMED
Published: April 2003

This paper presents a new methodology to extract visual data contained in noisy gray-level images such as mail envelopes. Since the intensity changes may occur over a large range of spatial scales in these and other like images, we adopt the multiscale approach to extract good quality data that might be used in further processing and recognition processes. We have already shown in a previous paper its effective use in full data extraction. In this paper, we will give an advanced formalism of this result, referred to as a top–down approach. Then, we will present a new and opposite approach, referred to as a bottom–up approach. The differences and characteristics of both approaches are highlighted. Experiments have been conducted on real life data from the data base provided by CEDAR at SUNY Buffalo, to assess the effectiveness of the proposed paradigm; this reveals its improved robustness and accuracy over the top–down approach; such a result might be useful for a wide range of applications in the field of image processing and enhancement.
SPACE-EFFICIENT ALGORITHMS FOR APPROXIMATING POLYGONAL CURVES IN TWO-DIMENSIONAL SPACE
Authors: CHEN DANNY Z. , DAESCU OVIDIU
Published: April 2003

Given an n-vertex polygonal curve P = [p1, p2, …, pn] in the 2-dimensional space R2, we consider the problem of approximating P by finding another polygonal curve [Formula: see text] such that the vertex sequence of P′ is an ordered subsequence of the vertices along P. The goal is to either minimize the size m of P′ for a given error tolerance ∊ (called the min-# problem), or minimize the deviation error ∊ between P and P′ for a given size m of P′ (called the min-∊ problem). We present useful techniques and develop efficient algorithms for solving the 2-D min-# and min-∊ problems under two commonly-used error criteria for curve approximations. Our algorithms improve substantially the space bounds of the previously best known results on the same problems while maintain the same time bounds as those of the best known algorithms. We further show that our 2-D techniques can be used to improve the time and space bounds for a special case of the 3-D min-# and min-∊ problems.
Lewis Acid-Mediated Carboxylation of Aryl- and Allylsilanes with Carbon Dioxide
Authors: Hattori Tetsutaro , Suzuki Yutaka , Miyano Sotaro
Published: April 2003

Aryl- and allylsilanes are carboxylated with CO2 with the aid of aluminum-based Lewis acids, to give aromatic and β,γ-unsaturated carboxylic acids in fair to good yields, respectively. Formation of the former is rationalized by an aromatic electrophilic substitution by CO2 activated by the Lewis acid, while the latter a nucleophilic addition of in situ-generated allylaluminum species to CO2.
Conflict resolution in women is related to trait aggression and menstrual cycle phase
Authors: Bond Alyson J. , Critchlow D. Gail , Wingrove Janet
Published: April 2003

Twenty‐four women with a diagnosis of premenstrual dysphoric disorder (PMDD) and 18 controls took part in a study of patterns of female aggression. They completed a version of the Conflict Tactics Scale for a premenstrual and a follicular phase of their menstrual cycle and for the past year. The Life History of Aggression was completed during a clinician interview. The women used more aggressive tactics to solve conflicts in the premenstrual than in the follicular phase, but the difference was only significant for the PMDD group. During the past year, reasoning was the most common strategy used by women to resolve conflicts, but verbal aggression was also prevalent. Although physical violence was less common, the prevalence of any act of violence was 33% in the controls and 62% in the clinical group. Women with PMDD used both verbal and physical aggression more frequently than the controls and had a higher lifetime history of aggression. Aggression by women toward partners was associated with a general tendency to act aggressively. Aggr. Behav. 29:228–238, 2003. © 2003 Wiley‐Liss, Inc.
Enhanced Hydrogenation Activity and Recycling of Cationic Rhodium Diphosphine Complexes through the Use of Highly Fluorous and Weakly‐Coordinating Tetraphenylborate Anions
Authors: van den Broeke Joep , de Wolf Elwin , Deelman Berth‐Jan , van Koten Gerard
Published: April 2003

The effect of the nature of the anion on the performance of ionic rhodium catalysts has received little attention. Herein it is shown that the use of highly fluorous tetraphenylborate anions can enhance catalyst activity in both conventional and fluorous media. For hydrogenation catalysts of the type [Rh(COD)(dppb)][X] {COD=1,5‐cis,cis‐cyclooctadiene; dppb=1,4‐bis(diphenylphosphino)butane; X=BF4− (1a), [BPh4]− (1b), [B{C6H4(SiMe3)‐4}4]− (1c), [B{C6H3(CF3)2‐3,5}4]− (1d), [B{C6H4(SiMe2CH2CH2C6F13)‐4}4]− (1e), [B{C6H4(C6F13)‐4}4]− (1f) and [B{C6H3(C6F13)2‐3,5}4]− (1 g)} the activity towards the hydrogenation of 1‐octene in acetone increased in the order 1c <1b <1e <1a <1d ~ 1f <1g with 1g being twice as active as the commonly applied 1a. Despite the fluorophilic character introduced by the substituted tetraarylborate anions, the presence of some perfluoroalkyl‐substituents in the cation was still required for achieving high partition coefficients. Therefore, [Rh(COD)(Ar2PCH2CH2PAr2)][X] {Ar=C6H4(SiMe2CH2CH2C6F13)‐4, X=[B{C6H3(C6F13)2‐3,5}4]− (3f); Ar=C6H4(SiMe(CH2CH2C6F13)2)‐4 and X=[B{C6H4(C6F13)‐4}4]− (2g)} were prepared, which were active in the hydrogenation of 1‐octene, 2g even more so than 3f. Both these highly fluorous catalysts could be recycled with 99% efficiency through fluorous biphasic separation, whereas the corresponding BF4− complex of 2g (2a) did not show any affinity for the fluorous phase.
High Atom Efficiency in Sc(OTf)3‐Catalyzed Allylation of Aldehydes with Tetraallyltin
Authors: Nagano Yoshifumi , Orita Akihiro , Otera Junzo
Published: April 2003

The high atom efficiency was achieved through addition of Ac2O in the Sc(OTf)3‐catalyzed allylation of aldehyde with tetraallytin in a 4 : 1 molar ratio.
Causes of homelessness in the UK: a dynamic analysis
Authors: Anderson Isobel , Christian Julie
Published: April 2003

This article presents an analysis of the causes of homelessness in the UK, and develops the notion that the bulk of the research has focused on ‘discrete’ causes of homelessness, which has been important for enhancing our knowledge, but has also led to gaps in our understanding. To this end, the article begins outlining the benefits of the pathways approach, acknowledging the potential contributions of this approach rather than fully developing the argument, and placing it in a wider context. This article concludes by discussing implications for a more dynamic explanation of homelessness and the impact that it is likely to have on both policy and research in the UK. Copyright © 2003 John Wiley & Sons, Ltd.
Erfolgsmodelle von Anlagenplanungsunternehmen in der Feinchemie
Authors: Schlüter V. , Hoff D.
Published: April 2003

Eine Reihe von unterschiedlich ausgerichteten Engineering‐Unternehmen hat sich auf die spezifischen Anforderungen der Planung von Anlagen für die Herstellung von Feinchemikalien und Pharmawirkstoffen spezialisiert. Den Auftraggebern wie auch den Dienstleistern stellt sich die Frage, welche Unternehmen bzw. Unternehmensmodelle die Kundenbedürfnisse in diesem Segment am besten treffen. Welche Beauftragungsform ist dabei die effizienteste? Ist es die Vergabe an einen Generalunternehmer, gegebenenfalls mit einer Lump‐Sum‐Turnkey‐Beauftragung? Oder fährt der Auftraggeber besser mit Einzelplanungs‐Aufträgen? Eine Studie mit dem Schwerpunkt mitteleuropäische Feinchemie‐ und Pharmaindustrie zeigt: Es gibt keine standardisierbare Engineering‐Lösung. Jedes Geschäftsmodell hat spezifische Vor‐ und Nachteile; daraus müssen sich die Partner ihr individuelles Muster entwerfen. Die jeweilige Vertragsform hängt von vielen Komponenten ab – vom Produkt, vom Zeit‐ bzw. Kostendruck und nicht zuletzt von der verbliebenen Engineering‐Kompetenz des Auftraggebers.
Eignung des Treibstrahlreaktors für reaktionskinetische Untersuchungen von heterogen‐gaskatalytischen Normaldruckreaktionen
Authors: Hesselbarth B. , Adler R.
Published: April 2003

No abstracts.
Performance Monitoring – Ein entscheidender Beitrag zur Optimierung der Betriebsführung
Authors: Dünnebier G. , v. Felde M.
Published: April 2003

No abstracts.
Einsatz eines Zweiphasenreaktors mit Vorsättiger für Mehrphasenreaktionen
Authors: Battsengel B. , Datsevich L. , Jess A. , Münnich C. , Peter S. , Turek T.
Published: April 2003

No abstracts.
Untersuchung der Abscheidung submikroner Aerosole im Unterdruckzyklon
Authors: Ober F. , Mayer M. , Büttner H.
Published: April 2003

No abstracts.
Diffusionslimitierter Stoffumsatz in Biopellets aus Pilzen
Authors: Horn H.
Published: April 2003

No abstracts.
Münsterberg's nightmare: Psychology and history in fin‐de‐siècle Germany and America
Authors: Stoffers Manuel
Published: April 2003

This article demonstrates that Hugo Münsterberg's presidential address “Psychology and History,” delivered to the American Psychological Association in 1898, should be understood in the German context of the 1890s. It constituted a response to a central feature of fin‐de‐siècle culture in Europe, the revolt against positivism. To be more precise, Münsterberg reacted against a new intellectual trend that was arising in Germany in the middle 1890s: the call for a historically oriented social psychology put forward by Wilhelm Dilthey—who was explicitly attacking Münsterberg's physiological conception of psychology—and new cultural historians like Karl Lamprecht and others who seemed to be putting Dilthey's program into practice. © 2003 Wiley Periodicals, Inc.
Synthesis of the First Organometallic Miktoarm Star Polymer
Authors: Wang Xiao Song , Winnik Mitchell A. , Manners Ian
Published: April 2003

The first organometallic miktoarm star copolymer, PFS(PI)3 (PFS = polyferrocenyldimethylsilane, PI = polyisoprene) with PDI of 1.04 was synthesized through anionic polymerization by using SiCl4 as the coupling agent and its well‐defined structure was characterized by using GPC and 1H NMR spectroscopy. In contrast to analogous diblock copolymers with similar PFS volume fractions which self‐assemble to form cylindrical structures, PFS(PI)3 formed unimolecular micelles in the PI selective solvent, hexane.

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Increased frequency of gastrin‐releasing peptide receptor gene mutations during colon‐adenocarcinoma progression
Authors: Glover Sarah C. , Tretiakova Maria S. , Carroll Robert E. , Benya Richard V.
Published: April 2003

Epithelial cells lining the mature human colon do not normally express receptors for gastrin‐releasing peptide (GRPR). In contrast, we have shown that when aberrantly expressed in functional form in colon cancer, this protein acted as a morphogen where it caused tumor cells to adopt a better‐differentiated phenotype. Importantly, GRPR mRNA is ubiquitously mutated in human colon cancer cell lines, with inactivating mutations detected in all cell lines not expressing functional receptor. Since colon cancers are heterogeneously differentiated, we set out to determine if the GRPR gene was mutated as a function of tumor cell differentiation in archived human colon cancers. We used laser capture microscopy to dissect out 67 regions of defined differentiation from 20 human colon cancers randomly selected from the UIC GI Tumor Bank. Except for two polymorphisms, the GRPR gene was not mutated in nonmalignant epithelial cells. In contrast, 42 distinct mutations were identified in malignant cells. Overall mutation number inversely correlated with the degree of tumor cell differentiation. Within any cancer, all GRPR mutations found within better‐differentiated cells were conserved in more poorly‐differentiated cells; while all poorly‐differentiated cells contained mutations resulting in GRPR pharmacological inactivation. These data suggest that accumulation of mutations within the GRPR gene ultimately resulting in the production of nonfunctional receptors may represent a previously unappreciated mechanism allowing for the dedifferentiation of tumor cells within any particular colon cancer; and that poorly‐differentiated tumor cells within any individual cancer may arise clonally from their better‐differentiated precursors. © 2003 Wiley‐Liss, Inc.
Development of a technique for modelling clay liner desiccation
Authors: Zhou Y. , Kerry Rowe R.
Published: April 2003

This paper presents a model for the analysis of clay liner desiccation in a landfill barrier system due to temperature effects. The model incorporates consideration of fully coupled heat‐moisture‐air flow, a non‐linear constitutive relationship, the dependence of void ratio and volumetric water content on stress, capillary pressure and temperature, and the effect of mechanical deformation on all governing equations. Mass conservative numerical schemes are proposed to improve the accuracy of the finite element solution to the governing equations. The application of the model is then demonstrated by examining three test problems, including isothermal infiltration, heat conduction and non‐isothermal water and heat transport. Comparisons are made with results from literature, and good agreement is observed. Copyright © 2003 John Wiley & Sons, Ltd.
On the LO‐polaron dispersion in D dimensions
Authors: Gerlach B. , Kalina F. , Smondyrev M.
Published: April 2003

We discuss the (LO)polaron dispersion for arbitrary spatial dimension D. Firstly, we review the existing literature; recent numerical work is critically analyzed. Secondly, we derive novel upper bounds for the dispersion, which incorporate the correct behaviour of the dispersion up to third order of the coupling constant α. A totally analytical evaluation is performed in the case D = 1. We compare the upper bounds with previously published lower bounds. Apart from a surrounding of zero dispersion, the relative deviation is on a few‐percent scale.
THz intersubband dynamics in p‐Si/SiGe quantum well emitter structures
Authors: Pidgeon C. R. , Murzyn P. , Wells J‐P. R. , Ikonic Z. , Kelsall R. W. , Harrison P. , Lynch S. A. , Paul D. J. , Arnone D. D. , Robbins D. J.
Published: April 2003

We report time‐resolved (ps) studies of the dynamics of intersubband transitions in p‐Si/SiGe multi‐quantum well structures in the FIR regime, ħω < ħωLO, utilizing the Dutch free electron laser, FELIX. The calculated scattering rates have been included in a rate equation model of the transient FIR intersubband absorption, and are in excellent agreement with our degenerate pump‐probe spectroscopy measurements where after an initial rise time determined by the resolution of our measurement, we determine a decay time of ∼10 ps. In strong contrast to similar measurements on p‐GaAs quantum wells, this is found to be approximately constant in the temperature range from 4 to 100 K, in good agreement with the predictions of alloy scattering in the Si0.7Ge0.3 wells.
Space–time approach to quantum chaos
Authors: Steiner F.
Published: April 2003

In the first part of this paper, it is shown that the energy levels of a quantum system, whose classical limit is chaotic, encode certain space–time properties of the corresponding classical system. To see this, one considers the semiclassical limit as Planck's constant tends to zero. As a generalization of Mark Kac's famous question, it is demonstrated that “one can hear the periodic orbits of a quantum billiard”. In the second part, some mathematical aspects of the semiclassical limit are reviewed. In order to deal with expressions that are mathematically easier to control, one does not work with the path integral directly, but instead with a smoothed kernel corresponding to a well‐defined Fourier integral operator. Applying then the techniques from microlocal analysis and pseudodifferential operators, one arrives at a semiclassical trace formula which is a generalization of the Gutzwiller trace formula originally derived from the path integral. In the third part of this paper, the Hadamard–Gutzwiller model is discussed whose classical limit is a strongly chaotic (Anosov) system. In order to derive exact orbit sum rules for this model, one requires the path integral on hyperbolic D‐space (D ≥ 2) which can be exactly solved by using the general lattice definition of path integrals in curvilinear coordinates.
Spatial correlation effects in the charged impurity distribution on the electronic properties of δ‐doped structures
Authors: van de Stadt A. F. W. , Koenraad P. M. , Shi J. M. , Wolter J. H. , Devreese J. T.
Published: April 2003

In this paper we will show that the δ‐doped GaAs/AlGaAs/GaAs quantum barrier is an ideal system to study deep centers in narrow doping layers with high doping density. By varying the Al content in the barrier, the distance between the Fermi‐level and the deep level can be tuned and therefore the number of populated states. By applying hydrostatic pressure this number can be further increased. Our measurements show that in these δ‐doped barrier structures electrons are trapped under hydrostatic pressure and that the quantum mobility is enhanced. This mobility enhancement can be explained by MC calculations which include the effect of the spatial correlation of the charge distribution when the deep state is the DX center and has a negative charge state. The fact that we do not observe a PPC effect or a significant change in the mobility after illumination at high pressure suggest that the Fermi‐level is pinned by a non‐metastable deep state like the A1 state or that the DX center is modified.
Toxicity Mode‐of‐action: Discrimination via Infrared Spectra And Eigenvalues of the Modified Adjacency Matrix
Authors: Pino Anna , Giuliani Alessandro , Benigni Romualdo
Published: April 2003

Aquatic toxicity can be partitioned into a number of mechanisms of action, the allocation of a given chemical to its particular mode being of fundamental importance for the toxicological risk assessment. We investigated the possibility to automatically allocate each chemical to its putative aquatic toxicity mode‐of‐action on the basis of the sole chemical physical information. In this paper, we refer to the four mode‐of‐action classes defined in Hermens' laboratory [1, 2]; the chemical descriptors used were the Infrared spectra and the Burden's Modified Adjacency Matrix Eigenvalues. At odds with Infrared spectrum, the Eigenvalues were able to allocate the chemicals into the different mechanism of action classes via a nonlinear discrimination method (K‐nearest neighbours classifier).
Axisymmetric rotational disk braking by a curved disk
Authors: Usha R. , Vimala P.
Published: April 2003

The hydrodynamic disk braking by an axisymmetric curved disk of arbitrary shape is investigated. A viscous fluid separates a rotating flat bottom disk and a non‐rotating axisymmetric curved upper disk. As the two disks are squeezed closer together, increased viscous torque is transmitted to the rotating bottom disk. A perturbation method is used to solve the governing equations of motion for small values of the parameter which is the ratio of the gapwidth to the radius of the disk. Constant force squeezing state is considered to study the braking characteristics, when the bottom disk rotates with constant angular velocity. It is observed that the curvature of the top disk strongly influences the braking characteristics.
Hydromagnetic free shear layers in rotating flows with magnetic field perpendicular to rotation vector and shear layers
Authors: Vempaty S. , Satyamurty P.
Published: April 2003

Following Hollerbach's work (1996) hydromagnetic free shear layers are analyzed when the applied magnetic field is perpendicular to both the rotation vector and vertical free shear layers. Analytical solutions have been obtained for the shear layer and interior regions. The physical features of the flow are discussed with special emphasis on meridional flow of electric current flux.
The nifk gene is widely expressed in mouse tissues and is up‐regulated in denervated hind limb muscle
Authors: Magnusson Caroline , Norrby Marlene , Libelius Rolf , Tågerud Sven
Published: April 2003

Denervation of skeletal muscle alters the expression of many genes, which may be important for establishing optimal conditions for reinnervation. Using the differential display technique we have attempted to discover neurally regulated genes in skeletal muscle. An mRNA that is up‐regulated in denervated hind limb muscle was identified and cloned. The cDNA encodes an RNA‐binding protein, which was discovered during the course of this work to be a nucleolar protein interacting with the fork‐head associated domain of the proliferation marker protein Ki‐67, and named NIFK. We show that the nifk gene is widely expressed in adult mouse tissues and that the expression is up‐regulated in denervated hind limb muscle. No difference between expression in perisynaptic and extrasynaptic portions of muscle was observed. The widespread expression in adult tissues suggests that the NIFK protein has other functions in addition to its interaction with Ki‐67, which is only expressed in proliferating cells.
Cycloid psychosis: a clinical and nosological study
Authors: PERALTA VICTOR , CUESTA MANUEL J.
Published: April 2003

Background. Despite its clinical relevance, the diagnosis of cycloid psychosis has been relatively neglected in the psychiatric literature and in the current nosological systems. This study examined the clinical validity and nosological status of the cycloid psychosis concept.

Method. Six-hundred and sixty psychotic in-patients were assessed for psychosis-related variables and diagnosed according to DSM-III-R, DSM-IV, ICD-10 and the Perris & Brockington criteria for cycloid psychosis. The cycloid psychosis diagnosis (N=68, 10·3%) was examined in regard to its discriminant validity, concordance with other psychotic disorders, and predictive validity in relation to schizophrenia and psychotic mood disorders. To address putative heterogeneity within cycloid psychosis, affective (N=38) and non-affective (N=30) subgroups were examined.

Results. Cycloid psychosis had good discriminant validity regarding other psychoses (95% of correctly classified cases) and poor concordance with individual diagnoses from the formal diagnostic systems (κ<0·22). Cycloid patients had levels of psychotic, disorganization and first-rank symptoms comparable to schizophrenia, and levels of affective symptoms in-between schizophrenia and mood disorders. Regarding most clinical variables and morbidity risk of mood disorders, cycloid psychosis was closer to mood disorders. Cycloid psychosis had higher psychosocial stressors than schizophrenia and mood disorders. Affective and non-affective groups of cycloid psychosis differed in a number of variables indicating an overall better outcome for the non-affective group.

Conclusions. Cycloid psychosis does not correspond closely to any DSM-III-R, DSM-IV or ICD-10 category of psychosis, and more specifically this nosological concept is not well represented by the different formal definitions of remitting psychotic disorders. Cycloid psychosis seems to be an heterogeneous condition in that affective and non-affective subgroups can be differentiated.
Eating disturbances in girls with diabetes: the contribution of adolescent self-concept, maternal weight and shape concerns and mother–daughter relationships
Authors: MAHARAJ S. I. , RODIN G. M. , OLMSTED M. P. , CONNOLLY J. A. , DANEMAN D.
Published: April 2003

Background. This study examined the relative contribution of adolescent self-concept, maternal weight and shape concerns (WSC), and mother–daughter relationships to eating disturbances among girls with type 1 diabetes mellitus (DM).

Method. Eighty-eight adolescent girls (mean=15·0 years, s.d.=2·2) and their mothers completed self-report measures of disordered eating and weight control behaviours, with teens also reporting on disturbed eating and body attitudes. Based on reported symptoms, adolescents were classified as highly (N=18), mildly (N=30) and non-eating disturbed (N=40). Self-concept was assessed by adolescent self-report. Mother–daughter relationships were assessed by adolescent self-report and by observed mother–daughter interactions that were rated using a macroanalytic coding system that assesses intimacy and autonomy in these relationships.

Results. Hierarchical regressions illustrated that adolescent self-concept deficits, maternal WSC, and impaired mother–daughter relationships significantly predicted eating disturbances in girls with DM, accounting for 57% of the variance. Mothers who engaged in dieting and binge-eating were more impaired in their ability to support their daughters' emerging autonomy. The quality of mother–daughter relationships partly mediated the influence of maternal WSC on adolescent eating disturbances. Moreover, the impact of maternal WSC and mother–daughter relationships on eating disturbances was mediated by adolescent self-concept.

Conclusions. Findings illustrate two pathways through which mother–daughter relationships may impact upon risk of eating disturbances in girls with DM and highlight the need to evaluate family-based interventions specifically tailored for this high-risk population.
The communists in rural Guangdong, 1928–1936
Authors: Chan Gordon Y. M.
Published: April 2003

Research on the subject of Chinese communism has long been marred by the “spotlight approach”, which, as Kathleen Hartford rightly criticises, “illuminates key actors and events, but leaves in the shadow the action transpiring in the corners of the historical stage”. Assuming that only a few great names and signal events bear relevance to its development, such an approach often produces simplified pictures of the Chinese communist revolution. During the last decade or so, however, an increasing number of historians have begun to take seriously the great complexities and diversities involved in this revolutionary movement. Using newly available communist Party sources, they have ventured to excavate forgotten or even deliberately ignored episodes in the history of the Chinese Communist Party (CCP). In so doing, they have not only expanded the scope of enquiry in Chinese communism but also provided new evidence for testing old interpretive structures. This article joins that trend by presenting the little-known story of the Communist struggle in rural areas of the Guangdong province from 1928 to 1936.
SPACE HIERARCHIES OF TWO-DIMENSIONAL ALTERNATING TURING MACHINES, PUSHDOWN AUTOMATA AND COUNTER AUTOMATA
Authors: OKAZAKI TOKIO , INOUE KATSUSHI , ITO AKIRA , WANG YUE
Published: April 2003

This paper investigates the space hierarchies of the language classes for two-dimensional Turing machines (2-TM's), two-dimensional pushdown automata (2-PDA's) and two-dimensional counter automata (2-CA's) with small space. We show that

(1) if L(n) is space constructible by a 2-TM, L(n) ≤ log n and L′(n) = o(L(n)), then strong 2-DSPACE(L(n)) – weak 2-ASPACE(L′(n)) ≠ ∅,

(2) if L(n) is space constructible by a 2-PDA, L(n) ≤ log n and L′(n) = o(L(n)), then strong 2-DPDA(L(n)) – weak 2-ASPACE(L′(n)) ≠ ∅, and

(3) if L(n) is space-constructible by a 2-CA, L(n) ≤ n and L′(n) = o(L(n)), then strong 2-DCA(L(n)) – weak 2-ACA(L′(n)) ≠ ∅,

(4) where strong 2-DSPACE(L(n)) (strong 2-DPDA(L(n)), strong 2-DCA(L(n))) denotes the class of sets accepted by strongly L(n) space-bounded deterministic 2-TM's (2-PDA's, 2-CA's), and weak 2-ASPACE(L′(n)) (weak 2-ACA(L′(n))) denotes the class of sets accepted by weakly L′(n) space-bounded alternating 2-TM's (2-CA's).

We also investigate the closure property of space-bounded alternating 2-PDA's and 2-CA's under complementation, and show that

(1) if L(n) = o( log log n), then the class of sets accepted by L(n) space-bounded alternating 2-PDA's is not closed under complementation, and

(2) if L(n) is space-constructible by a 2-CA, L(n) ≤ n and [Formula: see text], then the class of sets accepted by L′(n) space-bounded alternating 2-CA's is not closed under complementation.
A ROBUST AFFINE INVARIANT METRIC ON BOUNDARY PATTERNS
Authors: HAGEDOORN MICHIEL , VELTKAMP REMCO C.
Published: April 2003

Affine invariant pattern metrics are useful for shape recognition. It is important that such a metric is robust for various defects. We formalize these types of robustness using four axioms. Then, we present the reflection metric. This is an affine invariant metric defined for the large family of "boundary patterns". A boundary pattern is a finite union of n-1 dimensional algebraic surface patches in ℝn. Such a pattern may have multiple connected components. We prove that the reflection metric satisfies the four robustness axioms.
Differential effects of IL-12 on the generation of alloreactive CTL mediated by murine and human dendritic cells: a critical role for nitric oxide
Authors: Nishioka Yasuhiko , Wen Hua , Mitani Kayo , Robbins Paul D , Lotze Michael T , Sone Saburo , Tahara Hideaki
Published: April 2003

We examined the mechanisms involved in interleukin (IL)-12-mediated suppression of cellular immunity in mice using allogeneic mixed leukocyte reaction (MLR) stimulated by dendritic cells (DCs) in vitro and compared the effect of IL-12 on MLR in mice and humans. Although IL-12 stimulated human MLR, the addition of IL-12 or interferon-γ (IFN-γ) resulted in a dose-dependent suppression of MLR in mice. The treatment with NG-monomethyl-l-arginine (L-NMMA) completely abrogated IL-12- and IFN-γ-mediated suppression of MLR in mice. Furthermore, IL-12 enhanced the alloreactive cytolytic T lymphocyte (CTL) induction in human MLR, whereas the addition of L-NMMA was required to generate alloreactive CTLs in the presence of IL-12 in mice. Nitric oxide (NO) was detected only in mouse MLR. Murine DCs could produce NO, but neither human CD34+ cell- nor monocyte-derived DCs produced a detectable amount of NO. These results suggest that NO produced by DCs might play an important role in IL-12-mediated immune suppression in mice but not in humans.
Imatinib restores expression of CD62L in BCR-ABL-positive cells
Authors: Fruehauf S , Topaly J , Schad M , Paschka P , Gschaidmeier H , Zeller W J , Hochhaus A , Ho A D
Published: April 2003

Chronic myelogenous leukemia (CML) is characterized by aberrant trafficking of malignant hematopoietic progenitor cells in the peripheral blood. Expression of the cell adhesion molecule CD62L was reported to be significantly lower in CML patients than in normal controls. We studied whether the transcription of CD62L in CML cells is dependent on the activity of the BCR-ABL tyrosine kinase. Following addition of the Abelson (ABL) tyrosine kinase inhibitor imatinib (formerly STI571) to two BCR-ABL-positive cell lines (BV173, SD-1), we observed a dose-dependent increase in CD62L RNA levels of up to 45-fold by a quantitative, real-time polymerase chain reaction and an increase in the amount of cell surface-bound CD62L of up to 18-fold by quantitative flow cytometry, respectively. These data are validated by an increased CD62L expression in the bone marrow of patients (n=6) with advanced CML who received imatinib. Restoration of defective cell adhesion mediated via the CD62L pathway may be one mechanism of action of imatinib in BCR-ABL-positive leukemias.
Synthesis of Novel Selenium Tubular Structure
Authors: Chen Yuan-tao , Sun Qiao-yu , Li Hu-lin
Published: April 2003

Tubular selenium has been synthesized successfully by reducing selenious acid with ascorbic acid in the presence of primary amines (CnH2n+1NH2 with 10≤n≤16) at room temperature.
Teasing, rejection, and violence: Case studies of the school shootings
Authors: Leary Mark R. , Kowalski Robin M. , Smith Laura , Phillips Stephen
Published: April 2003

Media commentators have suggested that recent school shootings were precipitated by social rejection, but no empirical research has examined this claim. Case studies were conducted of 15 school shootings between 1995 and 2001 to examine the possible role of social rejection in school violence. Acute or chronic rejection—in the form of ostracism, bullying, and/or romantic rejection—was present in all but two of the incidents. In addition, the shooters tended to be characterized by one or more of three other risk factors—an interest in firearms or bombs, a fascination with death or Satanism, or psychological problems involving depression, impulse control, or sadistic tendencies. Implications for understanding and preventing school violence are discussed. Aggr. Behav. 29:202–214, 2003. © 2003 Wiley‐Liss, Inc.
Comparative Study on CuZnAl and CuMnZnAlNiFe Shape Memdory Alloys Subjected to Cavitation–Erosion
Authors: Pohl M. , Stella J. , Hessing C.
Published: April 2003

Fundamental structural features of alloys have a large influence on their stability towards cavitation‐erosion, a process caused by implosion of bubbles in fluids next to a surface. CuZnAl alloys and manganese bronzes of austenitic or martensitic nature were subjected to cavitation‐erosion conditions at ambient and lowered temperature (see Figure for a martensitic CuZnAl alloy before and after exposure). The austenitic alloys appear to be of higher stability.
Secondary embolization of a Helex occluder implanted into a secundum atrial septal defect
Authors: Peuster Matthias , Reckers Julia , Fink Christoph
Published: April 2003

We report on a 2‐year‐old patient with atrial septal defect with a stretched diameter of 11 mm. The defect was closed uneventfully by use of a 25 mm Helex device. There was only trivial residual shunting (1 mm at the cranial margin of the device). After 36 hr, routine postinterventional echocardiography confirmed device embolization into the pulmonary artery. The child was asymptomatic. Transcatheter device retrieval with snares of different sizes, bioptomes, and retrieval forceps failed due to the mismatch of the diameter of the device and the small diameter of the pulmonary artery. Therefore, the device was retrieved surgically and the ASD closed by primary sutures. Secondary embolization of a Helex device complicated the closure of an uncomplicated atrial septal defect with a device‐to‐defect ratio according to the manufacturer's suggestion due to a mechanism not yet understood. Cathet Cardiovasc Intervent 2003;59:77–82. © 2003 Wiley‐Liss, Inc.
Effizientere Anlagenplanung durch Modularisierung?
Authors: Kampczyk B. , Burdorf A. , Hicking B. , Schmidt‐Traub H.
Published: April 2003

No abstracts.
Evaluating irrigation scheduling of hydroponic tomato in Navarra, Spain
Authors: Lizarraga Alberto , Boesveld Harm , Huibers Frans , Robles Camilo
Published: April 2003

The correct supply of water and nutrients is important in hydroponic growing systems in order to use water efficiently, avoid stress situations, and control production.

The present study was conducted to evaluate two irrigation scheduling techniques for hydroponic tomato production in Navarra, northern Spain, related to the crop water requirements. The results show that although daily over‐irrigation was applied (45.7% of drainage), 18% of the total yield (35 kg m−2) was affected by blossom‐end rot problems, due to water stress suffered by the crop. Irrigation scheduling by time clock was not flexible enough to satisfy the varying crop water requirements through the day and during the season. With constant irrigation intervals and volumes, water and fertilisers were wasted during the morning (excessive irrigation) whereas during the afternoon, the plants suffered water stress. Irrigation scheduling by radiation method at a level of 0.81 MJ m−2, with some supplementary time clock irrigation applications during the hours of darkness (in order to keep the growing medium wet), appeared to be a good solution. Copyright © 2003 John Wiley & Sons, Ltd.
The structure and stability of Si60 and Ge60 cages: A computational study
Authors: Chen Zhongfang , Jiao Haijun , Seifert Gotthard , Horn Anselm H. C. , Yu Dengke , Clark Tim , Thiel Walter , Von Ragué Schleyer Paul
Published: April 2003

Structural studies of fullerene‐like Si60 and Ge60 cages using ab initio methods were augmented by density functional tight‐binding molecular dynamics (DFTB‐MD) simulations of finite temperature effects. Neither the perfect Ih symmetry nor the distorted Th structures are true minima. The energies of both are high relative to distorted, lower symmetry minima, Ci and T, respectively, which still preserve C60‐type connectivity. Both Si60 and Ge60 favor Ci symmetry cages in which Si and Ge vertexes exhibit either near‐trigonal or pyramidal geometries. These structural variations imply significant reactivity differences between different positions. The small magnetic shielding effects (NICS) indicate that aromaticity is not important in these systems. The inorganic fullerene cages have lower stabilities compared with their carbon analogs. Si60 is stable towards spontaneous disintegration up to 700 K according to DFTB‐MD simulations, and thus has potential for experimental observation. In contrast, Ge60 preserves its cage structure only up to 200 K. © 2003 Wiley Periodicals, Inc. J Comput Chem 24: 948–953, 2003