bluuebunny/crossref_metadata_2025_split huggingface dataset:
Load Mitigation with Bending/Twist‐coupled Blades on Rotors using Modern Control Strategies
Authors: Lobitz Don W. , Veers Paul S. 
Published: April 2003

AbstractThe prospect of installing blades that twist as they bend and/or extend on horizontal axis wind turbines provides opportunities for enhanced energy capture and/or load mitigation. Although this coupling could be achieved in either an active or a passive manner, the passive approach is much more attractive owing to its simplicity and economy. As an example, a blade design might employ coupling between bending and twisting, so that as the blade bends owing to the action of the aerodynamic loads, it also twists, modifying the aerodynamic performance in some way. For reducing loads the blades are designed to twist towards feather as they bend. For variable‐speed pitch‐controlled rotors, dynamic computer simulations with turbulent inflow show that twist coupling substantially decreases fatigue damage over all wind speeds, without reducing average power. Maximum loads also decrease modestly. For constant‐speed stall‐controlled and variable‐speed stall‐controlled rotors, significant decreases in fatigue damage are observed at the lower wind speeds and smaller decreases at the higher wind speeds. Maximum loads also decrease slightly. As a general observation, whenever a rotor is operating in the linear aerodynamic range (lower wind speeds for stall control and all wind speeds for pitch control), substantial reductions in fatigue damage are realized. Copyright © 2002 John Wiley & Sons, Ltd.
The History and State of the Art of Variable‐Speed Wind Turbine Technology
Authors: Carlin P. W. , Laxson A. S. , Muljadi E. B. 
Published: April 2003

AbstractEarly wind turbines used for performing mechanical work (pumping, grinding and cutting) optimized aerodynamics by being allowed to run at variable speed. Some of the earliest DC electric wind turbines were allowed to run at variable speed. With the advent of grid‐connected AC turbines, rotational speeds were limited in order to control the wind turbine AC frequency output to equal the grid frequency. With the advent of semiconductor devices, attempts began as early as the 1970s to allow variable‐speed operation of large‐scale turbines. The introduction of a new generation of high‐voltage, high‐speed power electronic components allows a wide range of variable‐speed operation for very‐large‐scale machines. Over the past 30 years a number of designs have been tested, a few of which have entered commercial operation. A number of these designs and their histories are described. A detailed description of a wide range of electrical methods for allowing variable‐speed operation is provided. Copyright © 2003 John Wiley & Sons, Ltd.
Sliding Mode Control for Efficiency Optimization of Wind Electrical Pumping Systems
Authors: Fernandez R. D. , Mantz R. J. , Battatotto P. E. 
Published: April 2003

AbstractWind energy conversion systems have been receiving increasing attention in recent years, particularly in remote areas, where power from the utility is not available or is costly to install. Among many applications, wind electrical systems are successfully used for pumping water. Owing to the non‐linear characteristics of these systems, their control is essential to attain high efficiency. In this work, concepts of sliding mode control are employed to guarantee global stability and to optimize the efficiency of a wind electrical water‐pumping system. The measurement of wind speed is avoided. A thorough analysis of stability and dynamic behaviour is realized. Simulation results are presented. Copyright © 2003 John Wiley & Sons, Ltd.
MEASUREMENT OF POLARIZED QUARK DISTRIBUTIONS AT HERMES
Authors:   on behalf of the HERMES Collaboration, BERNREUTHER STEFAN 
Published: April 2003

The HERMES experiment has measured double spin asymmetries in the cross section for deep–inelastic scattering of longitudinally polarized positrons on longitudinally polarized 3 He (1995), 1 H (1996/97), and 2 D (1998) targets. A kinematic range of 0.023 < x < 0.6, and 1 GeV 2 < Q2 < 15 GeV 2 has been covered. From these asymmetries, based on inclusive and semi–inclusive measurements, polarized quark distributions are extracted as a function of x for up [Formula: see text] and down [Formula: see text] flavors as well as for valence and sea quarks. In the measured range, the up quark polarization is positive while the down quark polarization is negative. The sea quark polarization is compatible with zero. In this analysis all sea quark polarizations have been assumed to be flavor symmetric. Presently HERMES is analyzing a high statistics 2 D data sample taken in 1999-2000. For these data it is possible to identify pions and kaons with a RICH detector which was installed in 1998. This will enable an extraction of the individual sea quark flavors [Formula: see text], [Formula: see text], and [Formula: see text] without any symmetry assumptions.
In vivo retroviral gene transfer by direct intrafemoral injection results in correction of the SCID phenotype in Jak3 knock-out animals
Authors: McCauslin Christine S. , Wine John , Cheng Linzhao , Klarmann Kim D. , Candotti Fabio , Clausen Peter A. , Spence Sally E. , Keller Jonathan R. 
Published: April 2003

Abstract
Efficient retroviral gene transfer to pluripotential hematopoietic stem cells (PHSCs) requires ex vivo culture in multiple hematopoietic growth factors (HGFs) to promote cell division. While treatment of PHSCs with HGF can render stem cells viable targets for retroviral infection, HGFs can promote differentiation, loss of self-renewal potential, and affect the homing/engraftment capacity of PHSCs. To avoid the negative impacts observed with ex vivo transduction protocols, we developed a murine model for in vivo retroviral infection by direct intrafemoral injection (DII), thus abolishing the need for removal of cells from their native microenvironment and the signals necessary to maintain their unique physiology. Using this approach we have demonstrated in vivo retroviral gene transfer to colony-forming units–c (CFU-c), short-term reconstituting cells, and PHSCs. Moreover, direct intrafemoral injection of Jak3 knock-out mice with retroviral particles encoding the Jak3 gene resulted in reconstitution of normally deficient lymphocyte populations concomitant with improved immune function. In addition, DII can be used to target the delivery of other gene therapy vectors including adenoviral vectors to bone marrow cells in vivo. Taken together, these results demonstrate that in vivo retroviral gene transfer by direct intrafemoral injection may be a viable alternative to current ex vivo gene transfer approaches.
Variations on a technique: enhancing children's recall using narrative elaboration training
Authors: Brown Deirdre , Pipe Margaret‐Ellen 
Published: April 2003

AbstractThe current study examined first, whether the positive effects demonstrated by the Narrative Elaboration Technique (NET) could be further enhanced when coupled with mental reinstatement of context (MR), prior to interview, and second, compared the efficacy of the NET at a two‐week delay and a nine‐month delay. In Study 1, 47 children took part as a class in a staged event about safety. Two weeks later they received a single training session, and the following day were interviewed with either the NET (n = 16), NET + MR (n = 17), or in a control condition (n = 14). Children trained with the NET reported approximately twice as much correct information, and were more accurate, than a control group who did not receive NET training, although the combination of the NET + MR did not result in a further significant enhancement of recall. In Study 2, 22 children took part in the safety event, and nine months later received a single training session, and were interviewed the following day with either the NET (n = 11), or in a control condition (n = 11). Children who received the NET training reported more correct information than those who did not. The practical applications of the NET and its variations are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
When auditory presentations should and should not be a component of multimedia instruction
Authors: Leahy Wayne , Chandler Paul , Sweller John 
Published: April 2003

AbstractBased on cognitive load theory, two experiments investigated the conditions under which audiovisual‐based instruction may be an effective or an ineffective instructional technique. Results from Experiment 1 indicated that visual with audio presentations were superior to equivalent visual‐only presentations. In this experiment, neither the auditory nor the visual material could be understood in isolation. Both sources of information were interrelated and were essential to render the material intelligible. In contrast, Experiment 2 demonstrated that a non‐essential explanatory text, presented aurally with similar written text contained in a diagram, hindered learning. This result was obtained because when compared to a diagram only format, the aural material was unnecessary and therefore created a redundancy effect. Differences between groups were stronger when information was high in complexity. It was concluded that the effectiveness of multimedia instruction depends very much on how and when auditory information is used. Copyright © 2003 John Wiley & Sons, Ltd.
Improving calibration without training: the role of task information
Authors: Rakow Tim , Harvey Nigel , Finer Sarah 
Published: April 2003

AbstractMedical students estimated probabilities that medical school applicants selected randomly from a defined population would be offered a place on the basis of information about eight characteristics of each one. Estimates were biased in favour of acceptance and this was unaffected by mere provision of base rate information. However, a first experiment showed that provision of this information reduced miscalibration after each candidate had been discussed within small groups of participants. A second experiment showed beneficial effects of providing people with the range of probability responses derived from a statistical model of how candidates' characteristics influenced whether or not they were offered a place. Numerical and graphical representations of this information both improved calibration but did so by having different effects on the distribution of participants' probability responses. Copyright © 2003 John Wiley & Sons, Ltd.
Are police video identifications fair to African–Caribbean suspects?
Authors: Valentine Tim , Harris Niobe , Piera Anna Colom , Darling Stephen 
Published: April 2003

AbstractAnalysis of lineups from criminal cases has demonstrated that video technology can produce lineups that are less biased against the suspect than live lineups, and that White suspects are less likely to be identified from a live lineup than suspects of other ethnic origins. The present study assessed the fairness of video lineups of White Europeans and of African–Caribbeans used in actual criminal cases. African–Caribbean and White European participants selected the suspect from each lineup on the basis of the original witness description of the culprit. There was no reliable difference in the fairness of video lineups as a function of the ethnic origin of the lineup members. It is concluded that, within the context of the video system studied, use of video can provide a safeguard against bias against ethnic minorities that may occur in live lineups. Copyright © 2003 John Wiley & Sons, Ltd.
A Donor–Acceptor Polymer with a Peculiar Negative‐Charge‐“Trapping” Characteristic
Authors: Casalbore‐Miceli G. , Gallazzi M.C. , Zecchin S. , Camaioni N. , Geri A. , Bertarelli C. 
Published: April 2003

AbstractVoltammetric and spectrophotometric measurements of poly(3,3″‐dipentoxy‐3′‐dicyanoethenyl‐2,2′:5′,2″‐terthiophene) (polyCN) films, in connection with other experimental evidence, reveal a normal oxidative, but a peculiar reductive behavior consisting of trapping of the negative charge during the cathodic scan. Another interesting property of polyCN films is the tendency to form strong intramolecular and intermolecular associations, probably charge‐transfer (CT) complexes. These properties could account for the fact that the photovoltaic performance does not improve when polyCN is blended with a polythiophene donor.
Patterning Spherical Surfaces at the Two‐Hundred‐Nanometer Scale Using Soft Lithography
Authors: Paul K.E. , Prentiss M. , Whitesides G.M. 
Published: April 2003

AbstractTwo soft lithographic techniques—topographically directed photolithography (TOP) and near‐field contact‐mode photolithography—have been used to pattern spherical surfaces with features as small as 175 nm. Each technique has the ability to pattern more than a 60° arc of a spherical surface, albeit with distortions at the edge. Use as an optical polarizer demonstrates an application of these types of patterned surface.
Factors Affecting the Stability of CdTe/CdS Solar Cells Deduced from Stress Tests at Elevated Temperature
Authors: Visoly‐Fisher I. , Dobson K.D. , Nair J. , Bezalel E. , Hodes G. , Cahen D. 
Published: April 2003

AbstractCdTe/CdS solar cells were subjected to heat stress at 200 °C in the dark under different environments (in N2and in air), and under illumination (in N2). We postulate that two independent mechanisms can explain degradation phenomena in these cells: i) Excessive Cu doping of CdS: Accumulation of Cu in the CdS with stress, in the presence of Cl, will increase the photoconductivity of CdS. With limited amounts of Cu in CdS, this does NOT affect the photovoltaic behavior, but explains the crossover of light/dark current–voltage (J–V) curves. Overdoping of CdS with Cu can be detrimental to cell performance by creating deep acceptor states, acting as recombination centers, and compensating donor states. Under illumination, the barrier to Cu cations at the cell junction is reduced, and, therefore, Cu accumulation in the CdS is enhanced. Recovery of light‐stress induced degradation in CdTe/CdS cells in the dark is explained by dissociation of the acceptor defects. ii) Back contact barrier: Oxidation of the CdTe back surface in O2/H2O‐containing environment to form an insulating oxide results in a back‐contact barrier. This barrier is expressed by a rollover in theJ–Vcurve. Humidity is an important factor in air‐induced degradation, as it accelerates the oxide formation. Heat treatment in the dark in inert atmosphere can stabilize the cells against certain causes of degradation, by completing the back contact anneal.
Highly Ordered Self‐Assembled Architectures of Modified Terpyridines on Highly Ordered Pyrolitic Graphite Imaged by Scanning Tunneling Microscopy
Authors: Wouters D. , Höppener S. , Lunkwitz R. , Chi L. , Fuchs H. , Schubert U.S. 
Published: April 2003

AbstractScanning tunneling microscopy has been used to study the adsorbed phases of functionalized terpyridines at the solid–liquid interface of highly ordered pyrolitic graphite (HOPG). Terpyridines are well‐known for their complexing behavior to transition metal ions, making them widely used ligands in organometallic and supramolecular chemistry. We found that solutions of 2,2′:6′,2″‐terpyridine‐4′‐oxydodecane (tpy‐O‐C12) and 2,2′:6′,2″‐4′‐oxyoctadecane (tpy‐O‐C18) form highly ordered two‐ dimensional (2D) arrays on HOPG in phenyloctane. For both compounds, large, well‐defined lamellar domains have been observed with domain sizes larger than 500 nm. Sequential scans of an area with two grain boundaries indicate that desorption–resorption is taking place along the domain edges. High‐resolution images of the lamella have been obtained, and the 2D packing within the lamella was determined in detail. The terpyridines align in long uniform double rows with their alkyl chains packing in an alternating, zipper‐like fashion. The terpyridines pack with the polar head‐groups head to head, and the observed size and shape of the molecules fit exactly to their modeled geometries.
High‐Quality Electrochromic Polythiophenes via BF3·Et2O Electropolymerization
Authors: Alkan S. , Cutler C.A. , Reynolds J.R. 
Published: April 2003

AbstractElectrochemical polymerization in the strong Lewis acid, boron trifluoride ethylether (BFEE), has been used to prepare electrochromic polythiophene (PTh) and its derivatives: poly(3‐methylthiophene) (PMeTh), poly(3‐bromothiophene) (PBrTh), and poly(3,4‐dibromothiophene) (PDBrTh). The polymerization processes and properties of the resultant films are compared, where possible, to those carried out in traditional organic electrochemical solvents. The polymerization of these high oxidation potential thiophene monomers in BFEE yielded good‐quality, homogenous, and smooth electroactive and electrochromic films that could be repeatedly switched in common electrochemical solvents up to 240, 1380, 560, and 420 cycles for PTh, PMeTh, PBrTh, and PDBrTh, respectively, for 50 % retention of electroactivity. A colorimetric study of these films showed distinctive color changes between red and blue as they were switched between reduced and oxidized states. These findings allow the use of commercially available high oxidation potential thiophene monomers to provide electrochromic polymers, avoiding the use of other custom‐synthesized monomers.
Controlling the Color of Cholesteric Liquid‐Crystalline Films by Photoirradiation of a Chiroptical Molecular Switch Used as Dopant
Authors: van Delden R.A. , van Gelder M.B. , Huck N.P.M. , Feringa B.L. 
Published: April 2003

AbstractUsing thin films of a cholesteric mixture of acrylates 2 and 3 doped with the chiroptical molecular switch (M)‐trans‐1, photocontrol of the reflection color between red and green is possible. This doped liquid‐crystal (LC) film can be used for photoinduced writing, color reading, and photoinduced locking (via polymerization) of chiral, optically written information.
Serologically documented loracarbef (Lorabid)‐induced immune thrombocytopenia
Authors: Aljitawi O.S. , Krishnan K. , Curtis B.R. , Bougie D.W. , Aster R.H. 
Published: April 2003

AbstractWe report here the first case of severe immune thrombocytopenia induced by a second‐generation cephalosporin antibiotic, Loracarbef. A 56‐year old white female developed acute severe thrombocytopenia associated with acute respiratory symptoms following administration of Loracarbef. She responded to Loracarbef withdrawal and systemic corticosteroid administration. Loracarbef‐dependent platelet‐reactive antibodies were demonstrable in her serum by flow cytometry. Am. J. Hematol. 73:41–43, 2003. © 2003 Wiley‐Liss, Inc.
Occult lymphoma cells prevalent in autologous marrow from non‐Hodgkin's diffuse lymphoma
Authors: Yokoyama Junkichi , Fujimiya Yoshiaki , Yamaguchi Toshikazu , Shiga Kiyoto , Saijo Yoshio , Groveman Debra S. , McBain John A. , Suzuki Youichi , Ebina Takusaburo 
Published: April 2003

AbstractThe most effective treatment for recurrent non‐Hodgkin's lymphoma (NHL) appears to be a high‐dose cytotoxic chemotherapy (HDC) followed by autologous bone marrow transplantation (ABMT). However, it has been suggested that the presence of occult lymphoma cells in harvested marrow may be responsible for a significant fraction of treatment failures after HDC/ABMT. The present study examined randomly accrued NHL patients, independent of their cytogenic grades, for the presence of cells bearing bcl‐2/immunoglobulin heavy chain (IgH) gene rearrangements in lymph node (LN) biopsies and the bone marrow by polymerase chain reaction (PCR) and Southern blot hybridization combined with a classical culturing technique. Among 41 NHL patients examined, bcl‐2/IgH translocations were evident in LN biopsies and marrow from each of 10 follicular lymphoma patients, but not in any samples from 31 newly diagnosed diffuse lymphoma patients. Marrow aspirates from several patients that were cultured using a one‐week “triggering culture” followed by an extended period of conventional culture resulted in emergence of a monoclonal, IgH‐rearranged, bcl‐2‐normal lymphoid cell population. Such outgrowth was specifically seen in cultures of diffuse lymphoma marrow (7 of 28 evaluable patients). Southern analysis for IgH rearrangement within LN biopsies and of cells cultured from marrow of individual diffuse lymphoma patients produced identical patterns, suggesting that the occult lymphoma cells present in harvested marrow were derived from the predominant lymphoma cell population represented within involved lymph nodes. The culture of histologically occult lymphoma from diagnostic marrow and analysis of the derived cells by Southern blot hybridization can be used to detect potentially aggressive lymphoma cells within harvested marrow, despite their lack of bcl‐2 gene rearrangement. Am. J. Hematol. 73:1–11, 2003. © 2003 Wiley‐Liss, Inc.
Iron in sickle cell disease: A review why less is better
Authors: Koduri Prasad Rao 
Published: April 2003

AbstractSickle cell anemia (SCA) is an inherited disorder of hemoglobin synthesis that is characterized by life‐long severe hemolytic anemia, attacks of pain crisis, and chronic organ system damage. A third of the hemolysis in SCA is intravascular and the resulting urinary losses of iron may lead to iron deficiency. There is no evidence of iron overload in SCA and iron deficiency may be more common than suspected, especially in men. Absence of bone marrow iron remains a gold standard for the diagnosis of iron deficiency in these patients. Although low serum ferritin is highly specific for the diagnosis of iron deficiency, its sensitivity is quite low in SCA because of non‐specific elevation due to increased red cell turnover. The kinetics of sickling is strongly concentration dependent such that small decreases in the mean corpuscular deoxyhemoglobin‐S concentration (MCHC‐S) cause a substantial delay in sickle hemoglobin polymerization. Prolongation of the ‘delay time of gelation’ in excess of the capillary transit time may allow the erythrocyte to traverse the capillary bed to escape to the arterial side before there is rheologic impairment of the erythrocyte from polymerization of sickle hemoglobin. Overt iron deficiency lowers the MCHC‐S and thereby decreases the sickling tendency and the severity of hemolysis. The clinical improvement in SCA following the induction of iron deficient erythropoiesis by repeated phlebotomies or by erythrocytapheresis has been reported. Prospective controlled studies are needed to evaluate further, the therapeutic strategy of inducing controlled iron‐deficient erythropoiesis in selected patients witb SCA. Am. J. Hematol. 73:59–63, 2003. © 2003 Wiley‐Liss, Inc.