bluuebunny/crossref_metadata_2025_split huggingface dataset:
MOVPE growth of InN: a comparison between a horizontal and a vertical reactor
Authors: Liu Yuhuai , Kimura Takeshi , Shimada Taka‐aki , Hirata Masaki , Wakaba Masaki , Nakao Masashi , Ji Shi‐Yang , Matsuoka Takashi 
Published: May 2009

AbstractThe MOVPE growth of InN by a horizontal reactor is compared with that by a vertical reactor. The phase diagram does not almost depend on the reactor structure, but rather the parameters such as V/III ratio and the growth temperature. The growth rate of InN in the horizontal reactor significantly increases in comparison with the vertical reactor due to the reduction of the stagnant layer thickness, the increases in the source supply to the substrate surface and the high concentration of source gases by narrowing flow channel. For the horizontal reactor, the polycrystalline phase appeared in the case of the low carrier‐gas flow‐rate and disappeared for the high carrier‐gas flow‐rate. These data suggest that increasing the carrier gas flow rate can suppress the gas phase reactions. In the case of the horizontal reactor, InN can be obtained at temperatures as high as 625 °C, compared with the maximum growth temperature of 575 °C in the vertical reactor. But the growth rates significantly decrease above 600 °C. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Epitaxy and characterisation of AlInGaN heterostructures for HEMT application
Authors: Khoshroo L. Rahimzadeh , Mauder C. , Behmenburg H. , Woitok J. , Zander W. , Gruis J. , Reuters B. , Schubert J. , Vescan A. , Heuken M. , Kalisch H. , Jansen R. H. 
Published: May 2009

AbstractIn this paper we report on the growth and charcterization of quaternary AlInGaN/AlN/GaN heterostructures, spanning a range from 26% to 82% AlN, 4% to 18% InN and 0% to 70% GaN in the barrier layer. All samples were grown in AIXTRON metal organic vapor phase epitaxy (MOVPE) reactors on 2″ sapphire substrates. Sample characterisation was performed using high resolution X‐ray diffraction (HRXRD), X‐ray reflection (XRR), photoluminescence spectroscopy (PL), atomic force microscopy (AFM) and Rutherford backscattering (RBS). Inductive sheet resistance measurements and Hall measurements in van der Pauw geometry provided electrical characterization. AFM measurements show closed layers, in HRXRD measurements pendellösung oscillations are visible even in asymmetric reciprocal space maps. Mobility and sheet carrier concentration reach state of the art values currently achieved for ternary structures showing the high degree of tunability in the quaternary nitride system. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dependence of annealing temperature on electrical properties of GaN MIS capacitors
Authors: Shibata E. , Kaneko M. , Kikawa J. , Horiuchi Y. , Otake H. , Chikamatsu K. , Yamaguchi A. , Fujishima T. , Nanishi Y. 
Published: May 2009

AbstractWe used capacitance‐voltage (C‐V) and capacitance deep‐level transient spectroscopy (C‐DLTS) methods to study the electrical properties of GaN metal‐insulator‐semiconductor (MIS) capacitors. The MIS capacitors consisted of SiO2/GaN, SiN/GaN, or SiO2/SiN/GaN, respectively, and annealing temperature was varied. From the C‐V characteristics, samples annealed at 400 °C had a large hysteresis, an insufficient accumulation in the measured bias range, and a specific ledge. These features relate with traps and fixed charge. For the SiO2/GaN and the SiO2/SiN/GaN interface, these features improved when the annealing temperature exceeded 600 °C. On the other hand, it is confirmed that the annealing treatment up to 800 °C was insufficient in the SiN/GaN interface.From the C‐DLTS analysis, a common trap with an activation energy of 0.7‐0.8 eV was observed from all the MIS capacitors, suggesting the existence of complexes of Si and surface defect on GaN. In the SiO2/GaN MIS capacitor annealed above 600 °C, traps with an activation energy of 50, 150, 180, and 630 meV were observed. The intensities of these peaks decreased with increasing annealing temperature and it is considered that they correlate with the improvement of depletion behavior. A specific trap with an activation energy of 0.32 eV was observed from SiN/GaN MIS capacitor and it agreed with that of the trap related to ledge estimated from the C‐V characteristics. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of length biased sampling of unobserved sojourn times on the survival distribution when disease is screen detected
Authors: Kafadar Karen , Prorok Philip C. 
Published: May 2009

AbstractData can arise as a length‐biased sample rather than as a random sample; e.g. a sample of patients in hospitals or of network cable lines (experimental units with longer stays or longer lines have greater likelihoods of being sampled). The distribution arising from a single length‐biased sampling (LBS) time has been derived (e.g. (The Statistical Analysis of Discrete Time Events. Oxford Press: London, 1972)) and applies when the observed outcome relates to the random variable subjected to LBS. Zelen (Breast Cancer: Trends in Research and Treatment. Raven Press: New York, 1976; 287–301) noted that cases of disease detected from a screening program likewise form a length‐biased sample among all cases, since longer sojourn times afford greater likelihoods of being screen detected. In contrast to the samples on hospital stays and cable lines, however, the length‐biased sojourns (preclinical durations) cannot be observed, although their subsequent clinical durations (survival times) are. This article quantifies the effect of LBS of the sojourn times (or pre‐clinical durations) on the distribution of the observed clinical durations when cases undergo periodic screening for the early detection of disease. We show that, when preclinical and clinical durations are positively correlated, the mean, median, and quartiles of the distribution of the clinical duration from screen‐detected cases can be substantially inflated—even in the absence of any benefit on survival from the screening procedure. Screening studies that report mean survival time need to take account of the fact that, even in the absence of any real benefit, the mean survival among cases in the screen‐detected group will be longer than that among interval cases or among cases that arise in the control arm, above and beyond lead time bias, simply by virtue of the LBS phenomenon. Published in 2009 by John Wiley & Sons, Ltd.
Development and evaluation of a system enhancing Second Life to support synchronous role‐based collaborative learning
Authors: De Lucia Andrea , Francese Rita , Passero Ignazio , Tortora Genoveffa 
Published: May 2009

AbstractResearch and commercial interest toward 3D virtual worlds are recently growing because they probably represent the new direction for the next generation of web applications. Although these environments present several features that are useful for informal collaboration, structured collaboration is required to effectively use them in a working or in a didactical setting. This paper presents a system supporting synchronous collaborative learning by naturally enriching Learning Management System services with meeting management and multimedia features. Monitoring and moderation of discussions are also managed at a single group and at the teaching level. The Second Life (SL) environment has been integrated with twoad hocdeveloped Moodle plug‐ins and SL objects have been designed, modeled, and programmed to support synchronous role‐based collaborative activities. We also enriched SL with tools to support the capturing and displaying of textual information during collaborative sessions for successive retrieval. In addition, the multimedia support has been enhanced with functionalities for navigating multimedia contents. We also report on an empirical study aiming at evaluating the use of the proposed SL collaborative learning as compared with face‐to‐face group collaboration. Results show that the two approaches are statistically undistinguishable in terms of performance, comfort with communication, and overall satisfaction. Copyright © 2009 John Wiley & Sons, Ltd.
Investigating the role of CMMI with expanding company size for small‐ to medium‐sized enterprises
Authors: Lester N. G. , Wilkie F. G. , McFall D. , Ware M. P. 
Published: May 2009

AbstractIn this article we show how the results from software process appraisals of ten small‐ to medium‐sized software development enterprises demonstrate that as companies become larger they naturally use an increasing number of practices within the Capability Maturity Model Integration (CMMI®). The companies involved in this study had no CMMI®experience prior to this work. We identify those practices that tend to be best followed by both small‐ and medium‐sized enterprises and those that tend to be introduced as the company size increases from small to medium. We conclude that the CMMI®appears to have an inherent roadmap for process improvement, buried within its explicit structure of capability levels that is driven by company expansion. The results of this study can be used by organisations to plan process improvement as they expand in size and staff complement. We further show how our results are consistent with the European Union's definition of a ‘Small’ and a ‘Medium’ sized enterprise. Copyright © 2009 John Wiley & Sons, Ltd.
The relationship between: Miller's living systems theory and Beer's viable systems theory
Authors: Nechansky Helmut 
Published: May 2009

AbstractThe paper investigates if a living system according to Miller's living systems theory is a viable system according to Beer's viable systems theory and vice versa. Miller's and Beer's theories are briefly reviewed and translated into one cybernetic approach. The comparison of their functional and structural commonalties and differences shows: Miller's theory allows simple structures, below the scope of Beer's approach, which are nevertheless viable, as examples from biology, anthropology and economy show. Beer's viable systems can be derived form Miller's living systems theory, i.e. Beer deals only with issues of viability that emerge with complex living systems. Short considerations of large social units suggest that their structures are not unequivocally determined and may be viable while deviating from Beer's approach, too. Yet such structures can be derived from Miller's theory. It is concluded that Miller's living systems theory covers viability more completely than Beer's viable systems theory. Copyright © 2009 John Wiley & Sons, Ltd.
Prenatal phencyclidine exposure alters hippocampal cell proliferation in offspring rats
Authors: Tanimura Atsushi , Liu Juan , Namba Takashi , Seki Tatsunori , Matsubara Yoichiro , Itoh Masanobu , Suzuki Toshihito , Arai Heii 
Published: May 2009

AbstractMultiple case reports have described pregnancy in phencyclidine hydrochloride (PCP) abusers. Characteristic clinical symptoms of PCP‐exposed infants have revealed neurobehavioral or physical abnormalities. We designed this study to evaluate whether chronic prenatal exposure to PCP during the last 2 weeks of gestation in rats produces alterations of hippocampal neurogenesis in offspring. Rats received repeated subcutaneous injection of PCP (5 mg/kg) once daily during the last 2 weeks of gestation. Control animals received subcutaneous injection of physiological saline during gestation. Dams receiving repeated PCP administrations showed markedly increased locomotor activities on days 1, 5, and 10 during the last 2 weeks of gestation. At 21 days after birth, 5‐bromo‐2′‐deoxyuridine (BrdU)‐positive cells of offspring were counted in the granule cell layer (GCL) and subgranular zone of the dentate gyrus. The numbers of BrdU‐positive cells in the GCL in male and female offspring of the PCP‐treated group were significantly increased by ∼77% compared with those from the control group. At 56 days, the number of surviving BrdU‐positive cells also remained to be increased by 74% in the GCL in PCP‐treated group. At 21 days, locomotor activities of offspring in the PCP‐treated group were significantly decreased by ∼30% compared with those in the control group. However, neuronal differentiation of newly formed cells and cell survival were not influenced at 5 weeks after BrdU injections. Some altered biochemical or physiological conditions of offspring from dams receiving repeated PCP injections during pregnancy could influence changes in cell proliferation in the GCL of offspring during early development. Changes to cell proliferation in the hippocampus may affect behavioral abnormalities during infancy in offspring. Synapse 63:729–736, 2009. © 2009 Wiley‐Liss, Inc.
First‐trimester fetal nasal bone length in an ethnic Chinese population
Authors: Sahota D. S. , Leung T. Y. , Chan L. W. , Law L. W. , Fung T. Y. , Chan O. K. , Lau T. K. 
Published: May 2009

AbstractObjectivesTo determine reference ranges of fetal nasal bone length (NBL) in a Chinese population and to assess the value of NBL measurement in screening for chromosomal defects in the first trimester.MethodsIn this prospective study the fetal profile was examined and the fetal NBL and crown–rump length (CRL) were measured in Chinese women presenting with singleton pregnancies for first‐trimester screening for aneuploidy between January 2004 and June 2007. Screening was performed on the basis of nuchal translucency (NT) measurement and maternal serum free β‐human chorionic gonadotropin and pregnancy‐associated plasma protein‐A levels.ResultsNBL was measured in 7543 fetuses, of which 7517 were euploid. The best fit equation for median NBL in euploid fetuses in relation to CRL was: NBL (mm) = 0.4593 + (0.0186 × CRL(mm)). The NBL for gestational age (GA, in days) was given by the equation NBL(mm) = 0.2392 + (0.0027 × GA). There was no correlation between log10(NBL multiples of the median (MoM)) and log10(NT MoM) in unaffected pregnancies (r = − 0.009; P = 0.43). Only two of the 11 cases with trisomy 21 had an NBL outside the 5th or 95th centiles of the reference range for euploid fetuses.ConclusionReference ranges for NBL in a Chinese population suitable for screening for aneuploidy between 11 and 13 + 6 weeks' gestation have been derived. The NBL in Chinese fetuses is similar to that of other ethnic groups. However, unlike the determination of presence vs. absence of the nasal bone, NBL measurement is unlikely to further improve screening for aneuploidy. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
The Role of the Platelet‐Rich Plasma in Accelerating the Wound‐Healing Process and Recovery in Patients Being Operated for Pilonidal Sinus Disease: Preliminary Results
Authors: Spyridakis Michail , Christodoulidis Gregory , Chatzitheofilou Constantine , Symeonidis Dimitris , Tepetes Konstantinos 
Published: May 2009

AbstractBackgroundBecause of the poor quality of life that results from the open technique (open excision and packing) for surgically treating pilonidal cyst disease, several alternatives that accelerate the wound‐healing process have been proposed. This study aimed to evaluate the effect of platelet‐derived growth factors on the healing process.MethodsFifty‐two patients with pilonidal sinus disease who underwent open excision and secondary closure of the surgical wound (n = 22) or additional local postoperative infusion of platelet‐derived growth factors (n = 30) were evaluated. Duration of total wound healing and time to return to normal activities were evaluated. Quality of life of patients in each group was assessed via a stabilized questionnaire.ResultsWound‐healing rates were much greater for the platelet group (p < 0.01). Complete healing of the surgical wound required 24 days for the platelet group while the respective time for the control group was more than 30 days (p < 0.01). Patients in the platelet group returned to their normal activities around the postoperative day 17 when mean wound volume was about 10 cc, while control group patients managed to do so around the postoperative day 25.ConclusionsThese data provide evidence that the use of platelet‐derived growth factors directly to the surgical wound enhances the healing process resulting in faster recovery of patients surgically treated for pilonidal sinus disease.
Impact of General Versus Local Anesthesia on Early Postoperative Cognitive Dysfunction Following Carotid Endarterectomy: GALA Study Subgroup Analysis
Authors: Weber Christian Friedrich , Friedl Hannah , Hueppe Michael , Hintereder Gudrun , Schmitz‐Rixen Thomas , Zwissler Bernhard , Meininger Dirk 
Published: May 2009

AbstractBackgroundThe aim of this study was to compare the influence of either general (GA) or local (LA) anesthesia on the postoperative neurocognitive outcome in patients undergoing carotid endarterectomy (CEA) in a randomized study. Therefore, we performed a subgroup analysis of the multicenter GALA study.MethodsA total of 40 patients were enrolled and randomized to receive either LA (n = 17) or GA (n = 23) anesthesia. The indication for intraoperative shunting was based on the intraoperative cognitive performance in the LA group and on the clinical experience of the surgeon in the GA group. Outcome measurements included patient performance on a neuropsychological Trail Making Test, evaluation of patients mood using the self‐report inventory BSKE, and serum levels of the neurobiochemical marker S100ß. The data were analyzed for each variable using a t‐test and were presented as the mean (SD). Differences in shunt frequency were analyzed performing a chi‐squared test. Group differences in the Trail Making Test, BSKE evaluation, and S100ß concentrations were derived from the analyses of covariances with repeated measurements using preoperative values as covariates.ResultsCompared to baseline, the S100ß concentrations increased significantly in the GA group [0.086 (0.038) vs. 0.061 (0.024) μg/l; p < 0.001] before unclamping of the carotid artery, whereas there were no changes in the LA group [0.068 (0.024) μg/l, p = 0.09 vs. 0.061 (0.021) μg/l, p = 0.09). Furthermore, we detected significant group differences after surgical intervention (GA 0.087 (0.031) μg/l; LA 0.06 (0.021) μg/l; p = 0.006). The postoperative neurocognitive performance in the Trail Making Test decreased significantly in the GA group, whereas there were no significant changes in the LA group. The self‐report inventory BSKE evaluation revealed no significant group differences.ConclusionsWe concluded that performing local anesthesia in patients undergoing CEA positively influenced early postoperative neurocognitive outcomes. Significant group differences in postoperative S100ß concentrations confirmed the beneficial effect of local anesthesia.
Thymoma with Dissemination: Efficacy of Macroscopic Total Resection of Disseminated Nodules
Authors: Yano Motoki , Sasaki Hidefumi , Yukiue Haruhiro , Kawano Osamu , Okuda Katsuhiro , Hikosaka Yu , Fujii Yoshitaka 
Published: May 2009

AbstractBackgroundAdvanced thymomas with disseminated nodules are difficult to manage, and the treatment strategy remains undefined.MethodsA total of 28 thymoma patients with pleural and/or pericardial disseminated nodules were treated at Nagoya City University Hospital. Among them, 21 patients underwent resection of thymoma and pleural disseminated nodules. These patients were reviewed in the present study.ResultsPreoperative steroid pulse therapy was performed in 14 patients. Macroscopic total resection of all tumors was achieved in 15 patients. Postoperative adjuvant radiotherapy was performed for the mediastinum in 20 patients and hemithoracic irradiation (HTR) in 11 patients. The overall survival rate of operated 21 patients was 73.1% at 5 years. The patients who underwent resection showed a better prognosis than the patients without resection (p = 0.0006). Relapse was diagnosed in 14 of 21 patients who underwent resection. Disease‐free survival was 67.5% at 1 year, 39.8% at 3 years, and 13.3% at 5 years. HTR alone did not improve the disease‐free survival. Among the patients who underwent total resection, relapse‐free survival was better than in the patients with subtotal resection (p = 0.009). Achievement of a trimodality therapy with preoperative steroid pulse, total resection, and postoperative HTR was associated with prolonged relapse‐free survival in the operated patients (p = 0.027, hazard ratio 6.452).ConclusionsPursuing total resection for thymoma and disseminated nodules may be beneficial for stage IV thymoma. The combination of preoperative steroid pulse therapy, macroscopic total resection, and postoperative HTR may prolong the interval to relapse, but it did not lead to cure.
Use of Ionic Liquid in Fabrication, Characterization, and Processing of Anodic Porous Alumina
Authors: Salerno Marco , Patra Niranjan , Cingolani Roberto 
Published: May 2009

Abstract
Two different ionic liquids have been tested in the electrochemical fabrication of anodic porous alumina in an aqueous solution of oxalic acid. It was found that during galvanostatic anodization of the aluminum at a current density of 200 mA/cm2, addition of 0.5% relative volume concentration of 1-butyl-3-methylimidazolium tetrafluoborate resulted in a three-fold increase of the growth rate, as compared to the bare acidic solution with the same acid concentration. This ionic liquid was also used successfully for an assessment of the wettability of the outer surface of the alumina, by means of liquid contact angle measurements. The results have been discussed and interpreted with the aid of atomic force microscopy. The observed wetting property allowed to use the ionic liquid for protection of the pores during a test removal of the oxide barrier layer.
Thermal tolerance and potential distribution of Carvalhotingis visenda (Hemiptera: Tingidae), a biological control agent for cat's claw creeper, Macfadyena unguis-cati (Bignoniaceae)
Authors: Dhileepan K. , Bayliss D. , Treviño M. 
Published: May 2009

AbstractThe specialist tingid, Carvalhotingis visenda, is a biological control agent for cat's claw creeper, Macfadyena unguis-cati (Bignoniaceae). Cat's claw creeper is an invasive liana with a wide climatic tolerance, and for biological control to be effective the tingid must survive and develop over a range of temperatures. We evaluated the effect of constant temperatures (0–45°C) on the survival and development of C. visenda. Adults showed tolerance for wider temperature ranges (0–45°C), but oviposition, egg hatching and nymphal development were all affected by both high (>30°C) and low (<20°C) temperatures. Temperatures between 20°C and 30°C are the most favourable for adult survival, oviposition, egg hatching and nymphal development. The ability of adults and nymphs to survive for a few days at high (40°C and 45°C) and low (0°C and 5°C) temperatures suggest that extreme temperature events, which usually occur for short durations (hours) in cat's claw creeper infested regions in Queensland and New South Wales states are not likely to affect the tingid population. The potential number of generations (egg to adult) the tingid can complete in a year in Australia ranged from three to eight, with more generations in Queensland than in New South Wales.