bluuebunny/crossref_metadata_2025_split huggingface dataset:
Manganese behaviour in ZnO layers deposited by magnetron sputtering for spintronic application
Authors: Abouzaid M. , Ruterana P. , Liu C. , Morkoç H. 
Published: January 2008

AbstractIn this work, we carry out structural analysis of ferromagnetic Mn‐doped ZnO thin films deposited by radio frequency magnetron sputtering, using transmission electron microscopy (TEM). On top of sapphire (0001) substrates, Mn rich precipitates and an interface reaction layer are observed follow‐ ing the deposition of Zn(Mn)O layers above 500 °C. The crystalline quality of ZnO layers deposited by magnetron sputtering is highly improved at 500 °C as well as the measured ferromagnetic response. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Visible and infrared electroluminescence from an Er‐doped n‐ZnO/p‐Si light emitting diode
Authors: Harako S. , Yokoyama S. , Ide K. , Zhao X. , Komoro S. 
Published: January 2008

AbstractEr‐doped ZnO/Si hetero‐junctions have been formed by laser ablating an Er‐contained ZnO target onto p‐Si(100) substrates. Light emitting diodes fabricated by using these samples exhibited bright green (536 nm and 556 nm), red (665 nm) and 1.54 µm emissions at room temperature. A light emission at 1180 nm was also observed. These emissions arose from intra‐4f transitions in Er3+ ions that were excited by impact excitation process. A threshold voltage of ∼10 V was achieved for emitting multi colors. Our results show a strong possibility of realizing the Si‐based light emitting devices by Er doing. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Rare earth doping of III‐nitride alloys by ion implantation
Authors: Lorenz K. , Alves E. , Roqan I. S. , Martin R. W. , Trager‐Cowan C. , O'Donnell K. P. , Watson I. M. 
Published: January 2008

AbstractThe implantation damage and rare earth (RE) luminescence in the wide band gap ternaries AlGaN and AlInN were studied and compared to GaN. For both ternaries lower damage levels were observed and in contrast to GaN, no surface amorphisation occurs during the implantation. Damage recovery of RE implanted GaN was studied for post implant annealing at temperatures between 800 °C and 1300 °C. The blue and IR Tm related luminescence intensity is seen to increase strongly with the annealing temperature. The two Tm lines observed at 478 nm and 465 nm are assigned to the 1G4 → 3H6 and the 1D2→3F4 transition, respectively. For GaN the line at 465 nm is fully quenched at RT while it becomes the dominant line for the ternaries. The blue luminescence intensity in the ternaries is significantly stronger than in GaN. Furthermore, AlInN shows a very high ratio of blue/IR luminescence. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Temperature dependent site change of In in AlN and GaN
Authors: Schmitz J. , Penner J. , Lorenz K. , Vianden R. 
Published: January 2008

AbstractHyperfine interaction studies by means of the perturbed angular correlation technique have been carried out on In implanted into GaN and AlN. After the implantation of the probe 111In with 160 keV and annealing of the radiation damage for 120 s at 1273 K, it is found, that in both materials 50–60% of the In probes occupy regular lattice sites at room temperature. The remaining second fraction is found in a quite different but relatively well defined lattice environment. The regular fraction increases at the cost of the second fraction to approx. 100% at a sample temperature of 600 K in GaN and 900 K in AlN. The effect is completely reversible, i.e. the fractions change back to their previous values if the sample is measured again at room temperature. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
GaInNAs(Sb) surface normal devices
Authors: Calvez S. , Laurand N. , Sun H. D. , Weda J. , Burns D. , Dawson M. D. , Harkonen A. , Jouhti T. , Pessa M. , Hopkinson M. , Poitras D. , Gupta J. A. , Leburn C. G. , Brown C. T. A. , Sibbett W. 
Published: January 2008

AbstractAfter a decade of intensive research on GaInNAs(Sb) on GaAs alloys, this paper summarizes some of the key properties of these III–V alloys and presents current progress in their exploitation in a variety of surface‐normal operating devices such as Vertical (External)‐Cavity Surface‐Emitting Lasers (V(E)CSELs) and SEmiconductor Saturable Absorber Mirrors (SESAMs). (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preface: phys. stat. sol. (a) 205/1
Authors: Kimura Tadamasa 
Published: January 2008

AbstractThis issue of physica status solidi (pps) contains contributed papers based on the invited talks at the 2nd Workshop on “Impurity Based Electroluminescent Devices and Materials” (IBEDM 2006) held in Nanki‐Shirahama, Wakayama, Japan, on 17–20 October 2006. The 1st Workshop “Impurity Based Electroluminescence in Wide Bandgap Semiconductors” was held in Santa Fe, New Mexico, USA, in April 2003 and was hosted by Dr. John Zavada, U.S. Army Research Office, and Prof. Andrew Steckl, University of Cincinnati. About 40 people from USA, Europe and Japan participated in the 1st Workshop and many useful and pleasant discussions took place. Owing to the success of the Santa Fe Workshop, the organizers came to an agreement to hold the 2nd Workshop in Japan in order to give greater opportunity for scientists in Asia to attend.The scope of IBEDM 2006 included various types of impurity based electroluminescent devices fabricated from semiconductors, oxides, inorganic and organic materials, as well as novel materials such as nano‐particles and nano‐wires. The following topics were covered at the workshop:1. Growth and structural properties of rare earth doped materials (semiconductors, oxides, organic materials).2. Basic optical properties of rare earth doped semiconductors.3. Optical processes of excitation and energy transfer in impurity doped materials.4. Luminescence of nano‐particles and nano‐wires doped with rare earth elements. 5. Device structures: Schottky, impact excitation, e‐h recombination.6. Full color electroluminescent materials and devices.7. Novel inorganic and organic luminescent materials and devices.8. Phosphor materials for full color and white color displays.We had 36 participants (US/Mexico, Europe, Asia/Japan), and 25 valuable presentations (all invited talks) by the top researchers from the world in this field. We had also two evening sessions, where hot topic discussions on impurity based silicon and widegap semiconductors lasted until late at night. All the participants stayed in the same hotel and spent four days together. We think that the concentrated discussions were very fruitful and gave the participants exciting new insights into the understanding of the luminescent devices and materials based on impurities.The papers contributed to this special issue of pss are based on the presentations and discussions given at IBEDM 2006. Before closing the Workshop, we came to an agreement that this Workshop was very valuable and that a 3rd Workshop should take place in near future. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Disorder effects in GaAs/InxGa1–xAs/GaAs quantum well delta doped with Mn
Authors: Aronzon B. , Lagutin A. , Rylkov V. , Pankov M. , Lashkul A. , Laiho R. 
Published: January 2008

AbstractWe present results of magnetic and transport measurements of GaAs/Ga1–xInxAs/GaAs quantum well structures containing a Mn δ‐layer separated from the quantum well by a 3 nm spacer. The kink observed in temperature dependence of the sample resistance and anomalous Hall effect give a hint for carrier spin polarization. Magnetization measurements show an unusual shifted hysteresis loop. The observed results are treated in the frame of long range fluctuation potential model. Parameters of the potential are estimated. It is shown that disorder determines the structural properties in spite of the hole mobility of about 2000 cm2/(V·s) being much higher than in presently known ferromagnetic two‐dimensional structures. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Current‐driven switching of a small‐polaron semiconductor to a meta‐stable conductor
Authors: Emin D. 
Published: January 2008

AbstractMany materials with low‐mobility charge carriers manifest current‐driven electronic switching between low‐conductivity and high‐conductivity transport. Available measurements suggest that the low‐conductivity carriers of these switches form small polarons. Here a mechanism is described via which driving a sufficiently high current through a material whose carriers form small polarons destabilizes them with respect to forming free carriers. The electrical conductivity then rises sharply since a free‐carrier's mobility is many orders of magnitude higher than that of a small polaron. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Temperature dependence of hopping‐edge in amorphous hydrogenated silicon
Authors: Murayama Kazuro , Hoshino Takuya , Ogiwara Chisato 
Published: January 2008

AbstractLuminescence peak energy of amorphous hydrogenated silicon (a‐Si:H) increases with excitation energy in the Urbach tail and in the higher excitation energy range the peak energy is constant. The excitation energy at which the peak energy turns from increase to constant is shown to be understood as the hopping‐gap. The hopping‐gap decreases with temperature as in the case of the optical bandgap. Furthermore, it is discussed by comparing with the luminescence in porous Si that the luminescence in a‐Si:H may be due to the radiative recombination of electron‐hole pairs in hydrogen‐free Si nanostructures. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Current challenges for FDA‐regulated bioanalytical laboratories for human (BA/BE) studies, Part II: recent FDA Inspection trends for bioanalytical laboratories using LC/MS/MS methods and FDA Inspection readiness preparation
Authors: Chow Frank , Lum Steven , Ocampo Arlene , Vogel Paul 
Published: January 2008

AbstractThis article is the second of a three‐part series that deals with the recent Food and Drug Administration (FDA) inspectional trends for bioanalytical laboratories performing analysis for human bioavailability (BA)/bioequivalence (BE) studies. While the FDA compliance expectations have been published in various FDA guidances, as well as the Compliance Program Guidance Manual for current Good Manufacturing Practice and Good Laboratory Practice (as discussed in Part 1 of this series), there are no specific regulations that mandate the operation and control of the bioanalytical laboratories conducting analyses for human BA/BE studies. It is apparent that the compliance standards and analytical testing requirements have been subject to a dynamically evolving process, slowly developed through several workshops jointly sponsored by the FDA and the pharmaceutical industry in the past decade. As the FDA expectations in the practices of bioanalytical laboratories become clearer, an increased trend is observed for the number of FDA 483 observations and untitled letters issued. This article provides a detailed analysis of the current FDA guidance and apparent expectations based on inspectional trends observed. In addition, the compliance and scientific basis of these dynamically evolving regulatory issues are also discussed, where applicable. Copyright © 2008 John Wiley & Sons, Ltd.
Better medicines for children: clinical investigation of medicinal products in the paediatric population ‐ a QA perspective
Authors: Fortwengel Gerhard , Ostermann Herwig , Staudinger Roland 
Published: January 2008

AbstractCurrently the number of medicinal products labelled for paediatric use is limited. Clinical trials involving children are surely amongst the most challenging types of studies performed from a scientific, ethical and medical perspective. The article provides an outline of critical issues to be considered when developing drugs in this population. Copyright © 2008 John Wiley & Sons, Ltd.
What's New?
Authors: Bens Catherine M. , Clemons Stephanie 
Published: January 2008

AbstractThe What's New? section in the Quality Assurance Journal aims to draw attention to items of importance to QA professionals. There is usually a three‐month interval between final submission of manuscripts and distribution of the journal. For this issue, the entries in the What's New? section arise from the period of 1 December 2006 to 28 February 2007. If you feel that there is any other new information that should be brought to the attention of readers, please let us know by e‐mailing rha@verdandi.ch. Copyright © 2008 John Wiley & Sons, Ltd.
Amino‐group‐specific natural abundance nitrogen isotope ratio analysis in amino acids
Authors: Zhang Lin , Altabet Mark A. 
Published: January 2008

AbstractAmino acid (AA) nitrogen (N) stable isotope ratio analysis has found a wide variety of important applications including indication of the trophic level of an organism, tracing N transfer within food webs, and monitoring of AA resynthesis during heterotrophic microbial reworking of organic matter. Despite its utility, the current methodology is difficult to employ consistently for natural abundance level precision. Here, we report a new and robust method for high‐precision N‐compound‐specific isotope analysis (N‐PCIA) for single‐N‐containing AAs and N‐position‐specific isotope analysis (N‐PSIA) for poly‐N AAs. First the amino‐N in AAs was liberated and oxidized to NO by hypochlorite at high pH. The NO produced was then quantified colorimetrically with excess hypochlorite quenched using arsenite. Subsequently, buffered azide was used to reduce NO to N2O for isotope ratio analysis using a purge‐and‐trap isotope ratio mass spectrometer. In the case of glycine δ15N, the average precision was SD = 0.3‰. Reaction yields and labeling experiments show that this oxidation reaction is highly specific, targeting the α‐amino group (peptide‐N) of most poly‐N AAs. This permits specific determination of the δ15N of peptide‐N in arginine, tryptophan, and histidine. In the case of lysine, however, the side‐chain amino group was found to be partially labile to hypochlorite oxidation. Using isotope fractionation factors estimated from single‐N analogues of lysine, the intramolecular δ15N of lysine was calculated by mass balance, and this generally agreed with results for the same sample material analyzed by a previously published enzymatic method. Our method has the advantages of being relatively rapid, robust, and applicable to all poly‐N AAs. We have also found it to work well for determining total δ15N of amino‐N in complex sample matrices that have not been susceptible to previous approaches. Copyright © 2008 John Wiley & Sons, Ltd.
Effects of resource allocation policies for reducing project durations: a systems modelling approach
Authors: Lee Zee Woon , Ford David N. , Joglekar Nitin 
Published: January 2008

AbstractMinimizing duration is critical to success in many development projects. Resource allocation policies during such projects determine the fractions of resources that are to be assigned to constituent tasks. The choice of allocation policy can strongly influence project durations. But policies for reduced project duration are difficult to design and implement because of closed loop flows of work that generate dynamic demand patterns and delays in shifting resources among activities. Resource demand estimates and resource adjustment times are two policy features that managers can readily alter to influence project durations. These features are used to describe allocation policies in a relatively simple project model. Myopic and foresighted policies are distinguished by their use (or lack thereof) of rework and multiple backlogs in allocation. Optimal policies under perfect and limited managerial control are described by testing myopic and foresighted policies across a range of project complexities and adjustment times under deterministic and uncertain conditions. Counter‐intuitive results from this analysis indicate that minimum resource allocation delay does not produce minimum durations, and increasing uncertainty decreases durations under certain conditions. The model is used to explain these results. Managerial implications and future research topics are discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Evaluation of Protocol Uniformity Concerning Laparoscopic Cholecystectomy in The Netherlands
Authors: Wauben Linda S. G. L. , Goossens Richard H. M. , van Eijk Daan J. , Lange Johan F. 
Published: January 2008

AbstractBackgroundIatrogenic bile duct injury remains a current complication of laparoscopic cholecystectomy. One uniform and standardized protocol, based on the “critical view of safety” concept of Strasberg, should reduce the incidence of this complication. Furthermore, owing to the rapid development of minimally invasive surgery, technicians are becoming more frequently involved. To improve communication between the operating team and technicians, standardized actions should also be defined. The aim of this study was to compare existing protocols for laparoscopic cholecystectomy from various Dutch hospitals.MethodsFifteen Dutch hospitals were contacted for evaluation of their protocols for laparoscopic cholecystectomy. All evaluated protocols were divided into six steps and were compared accordingly.ResultsIn total, 13 hospitals responded—5 academic hospitals, 5 teaching hospitals, 3 community hospitals—of which 10 protocols were usable for comparison. Concerning the trocar positions, only minor differences were found. The concept of “critical view of safety” was represented in just one protocol. Furthermore, the order of clipping and cutting the cystic artery and duct differed. Descriptions of instruments and apparatus were also inconsistent.ConclusionsPresent protocols differ too much to define a universal procedure among surgeons in The Netherlands. The authors propose one (inter)national standardized protocol, including standardized actions. This uniform standardized protocol has to be officially released and recommended by national scientific associations (e.g., the Dutch Society of Surgery) or international societies (e.g., European Association for Endoscopic Surgery and Society of American Gastrointestinal and Endoscopic Surgeons). The aim is to improve patient safety and professional communication, which are necessary for new developments.
The Use of CEEA 34 in Stapled Hemorrhoidectomy: Suggested Modifications in Technique
Authors: Chew M. H. , Tan W. S. , Eu K. W. 
Published: January 2008

AbstractStapled hemorrhoidectomy has been shown to be superior to conventional hemorrhoidectomy in numerous randomized, controlled trials and systemic reviews, with less postoperative pain and faster recovery. Premium Plus CEEA 34 has been recently introduced for use in stapled hemorrhoidectomy. The use of this stapler requires some modifications in technique.
Value of a Systematic Operative Protocol for Cocaine Body Packers
Authors: Veyrie Nicolas , Servajean Stéphane , Aissat Abdelhalim , Corigliano Nicola , Angelakov Céline , Bouillot Jean‐Luc 
Published: January 2008

AbstractBackgroundInternal concealment of illicit drugs during international drug traffic represents an important problem in developed countries. These drug traffickers are called “body packers.” The aim of this study was to analyze retroprospectively the surgical indications and complications for cocaine body packers and to describe our systematic operative protocol.MethodsFrom January 1997 to December 2005, 1,181 cocaine body packers were admitted to our Medico‐Judiciary Emergency Department. All patients had the same medical surveillance protocol. Nineteen patients required surgical procedure to remove drug packets.ResultsThirteen patients had obstruction or intestinal retention (68%). Suspicion of packet rupture or cocaine intoxication occurred in six patients (32%). Zero to three enterotomies were necessary during laparotomy. No deaths occurred. One pouch abscess required relaparotomy and one wound abscess was treated medically. The median hospital stay was 7 days (range: 5–30 days).ConclusionsFew cocaine body packers required a laparotomy. Our systematic operative protocol allowed intestinal clearance and caused acceptable morbidity rate.
Infraumbilical Anterior Retroperitoneal Exposure of the Lumbar Spine in 128 Consecutive Patients
Authors: Brewster Luke , Trueger Nathan , Schermer Carol , Ghanayem Alex , Santaniello John 
Published: January 2008

AbstractBackgroundAnterior spinal fusion can be approached through a retroperitoneal exposure lessening the risks of intra‐abdominal exploration. The aim of this study is to report the complication rate and risk factors associated with anterior spinal fusion.MethodsA retrospective review and analysis of 128 consecutive patients undergoing anterior lumbar fusion was performed looking to correlate potential risk factors with known serious complications of this operation such as vein injury, deep vein thrombosis, pulmonary embolism, and death.ResultsThe overall complication rate was 15.5%, with 7.75% being considered serious complications. The most common complication was vein injury (5.4%), but no blood transfusions were required. Postoperatively, there was one death (0.8%), one pulmonary embolism, and one intraoperative hypoxic episode of undetermined etiology. Univariate analysis showed that vein injury was associated with increased operative time (p <. 001) and associated with increased blood loss (p =. 02) but not increased length of stay (p =. 13). By multivariate analysis, operative time and length of stay were influenced by the approach of the operation (anterior alone versus anterior and posterior fixation), but not by the presence of vein injury or blood loss.ConclusionsIn this large series of patients undergoing anterior spinal fusion by a dedicated surgical team, there was a single death, and although vein injury was the most frequent serious complication, it did not lead to an increase in operative time or length of stay.
Transverse nonlinear instability for two-dimensional dispersive models
Authors: Rousset F. , Tzvetkov N. 
Published: January 2008

We present a method to prove nonlinear instability of solitary waves in dispersive models. Two examples are analyzed: we prove the nonlinear long time instability of the KdV solitary wave (with respect to periodic transverse perturbations) under a KP-I flow and the transverse nonlinear instability of solitary waves for the cubic nonlinear Schrödinger equation.

Résumé
On présente une méthode pour prouver l'instabilité non-linéaire d'ondes solitaires dans des modèles dispersifs. Deux exemples sont analysés : on prouve l'instabilité de l'onde solitaire de KdV (par rapport à des perturbations transverses périodiques) dans l'équation de KP-I et l'instabilité transverse nonlinéaire des ondes solitaires de l'équation de Schrödinger non-linéaire cubique.
Minimizers of Dirichlet functionals on the $n$-torus and the weak KAM theory
Authors: Wolansky G. 
Published: January 2008

Given a probability measure

μ

on the

n

-torus

\mathbb{T}^{n}

and a rotation vector

\boldsymbol{P} \in \mathbb{R}^{n}

, we ask whether there exists a minimizer to the integral

\int _{\mathbb{T}^{n}}|\mathrm{∇}\phi + \boldsymbol{P}|^{2}\:d\mu

. This problem leads, naturally, to a class of elliptic PDE and to an optimal transportation (Monge–Kantorovich) class of problems on the torus. It is also related to higher dimensional Aubry–Mather theory, dealing with invariant sets of periodic Lagrangians, and is known as the “weak-KAM theory”.

Résumé

Etant donnés une mesure

μ

sur le tore

n

-dimensionnel

\mathbb{T}^{n}

et un vecteur de rotation

\boldsymbol{P} \in \mathbb{R}^{n}

, on étudie la question de l'existence d'un minimiseur pour l'intégrale

\int _{\mathbb{T}^{n}}|\mathrm{∇}\phi + \boldsymbol{P}|^{2}\:d\mu

. Ce problème conduit naturellement à une classe d'équations aux dérivées partielles elliptiques et à une classe de problèmes de transport optimal (Monge–Kantorovich) sur le tore. Il est aussi lié à la théorie d'Aubry–Mather en dimension supérieure, qui traite les ensembles invariants pour des Lagrangiens périodiques, connue sous le nom de théorie KAM faible.