bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physical characterization of thin‐film solar cells
Authors: Durose Ken , Asher Sally E. , Jaegermann Wolfram , Levi Dean , McCandless Brian E. , Metzger Wyatt , Moutinho Helio , Paulson P.D. , Perkins Craig L. , Sites James R. , Teeter Glenn , Terheggen Mathias 
Published: April 2004

AbstractThe principal techniques used in the physical characterization of thin‐film solar cells and materials are reviewed, these being scanning probe microscopy (SPM), X‐ray diffraction (XRD), spectroscopic ellipsometry, transmission electron microscopy (TEM), Auger electron spectroscopy (AES), secondary‐ion mass spectrometry (SIMS), X‐ray photoelectron spectroscopy (XPS), photoluminescence and time‐resolved photoluminescence (TRPL), electron‐beam‐induced current (EBIC) and light‐beam‐induced current (LBIC). For each method the particular applicability to thin‐film solar cells is highlighted. Examples of the use of each are given, these being drawn from the chalcopyrite, CdTe, Si and III–V materials systems. Copyright © 2004 John Wiley & Sons, Ltd.
Polymeric stationary phase, based on (R,R)‐tartramide and bisphenol S, with potential chiral properties
Authors: Jabłońska‐Pikus T. , Charmas W. , Podkościelna B. , Gawdzik B. 
Published: April 2004

AbstractA new polymeric stationary phase with potential chiral properties, obtained by the chemical modification of the parent copolymer of dimethacrylate esters of bisphenol S and divinylbenzene, is presented. Hydroxyl functional groups present in the copolymer chemical structure are blocked by optically active selectors of (R,R)‐tartramide derivatives. The influence of the chemical modification of the parent copolymer on its porous structure has been studied. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2566–2574, 2004
Permeation, diffusion, and sorption of dimethyl ether in fluoroelastomers
Authors: Grazia De Angelis Maria , Cesare Sarti Giulio , Sanguineti Aldo , Maccone Patrizia 
Published: April 2004

AbstractThe permeation, diffusion, and sorption of dimethyl ether into a series of commercial fluoroelastomers were characterized at various pressures and temperatures. The polymers under study were based on tetrafluoroethylene and contained various amounts of other perfluorinated monomers: perfluoromethylvinylether, hexafluoropropylene, and a partially fluorinated monomer, vinylidene fluoride (VDF). These polymers were also filled with inorganic particles and cured with different techniques. The permeation rate of dimethyl ether in the elastomers examined, as well as the solubility value, increased as the content of the nonperfluorinated monomer (VDF) increased, and this was consistent with the solubility parameter theory. The diffusion coefficients, at a fixed concentration, had rather similar values for most of the elastomers examined. Both the permeability and diffusivity increased with temperature, and the corresponding activation energies were obtained for two selected polymers. The solubility of dimethyl ether, at a fixed temperature and activity, showed a linear dependence versus the weight fraction of the partially fluorinated monomer (VDF) in the polymeric matrix. The effect of the filler on the sorption and transport properties was also considered: the addition of the filler lowered the permeability and diffusivity, whereas the solubility was generally increased with respect to the crosslinked rubber. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1987–2006, 2004
Morphology of polypropylene films treated in CO2plasma
Authors: Aouinti Mohammed , Gibaud Alain , Chateigner Daniel , Poncin‐Epaillard Fabienne 
Published: April 2004

AbstractOne of the most important claims for the plasma technique as a surface treatment is that it modifies only a few atomic layers of materials. However, with polymers, this assumption must be carefully verified to keep the bulk mechanical properties constant. Besides the oxidation of the film, with specific plasma conditions such as high power and duration, the polypropylene film structure is also modified in the bulk through vacuum ultraviolet absorption and thermal relaxation. This change is associated with smectic‐ and amorphous‐phase transformation into an α‐monoclinic phase, with a rapid rate for the smectic transformation and a slower rate for the amorphous transformation. At the same time, the crystallite size increases, and the polypropylene film texture is planar and moderated (1.7 mrd at the maximum of the distribution, with a discharge power of 100 W and a treatment duration of 10 min). © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2007–2013, 2004
Solid polymer electrolytes X: Preparation and characterizations of polyether–siloxane, organic–inorganic, hybrid nanocomposites complexed with lithium perchlorate
Authors: Liang Wuu‐Jyh , Wu Chien‐Pang , Kuo Ping‐Lin 
Published: April 2004

AbstractOrganic–inorganic hybrid nanocomposites of poly(ethylene glycol)/siloxane were obtained via the sol–gel approach. In these composites, nanometric siloxane heterogeneity was embedded into a polymer matrix with a covalent bond at the interfaces. The 29Si magic‐angle spinning (MAS) spectrum exhibited a high degree of condensation through the relative abundance of T0 [RSi(OR)3], T1 [RSi(OR)2(OSi)], T2 [RSi(OR)(OSi)2], and T3 [RSi(OSi)3] silicone nuclei. The effect of lithium salt concentration on ionic interaction, conductivity, and thermal properties of these composite electrolytes were investigated by Fourier transform infrared spectroscopy, DSC, thermogravimetric analysis, alternating current impedance, and solid‐state 7Li MAS NMR measurements. These observations indicated that the different types of complexes by the interactions of Li+ and ClO ions are formed within a hybrid host, and the formation of transient crosslinks between Li+ ions and the ether oxygens results in an increased glass‐transition temperature of the polyether segment and decomposed rate of composite electrolyte. 7Li MAS NMR measurements revealed the changes in line shape of lithium resonances with different LiClO4 contents, suggesting that a significant degree of ionic association is present in the polymer‐salt complexes. The behavior of ion transport in these composite electrolytes was correlated with the interactions between ions and polymer host. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1928–1937, 2004
Thermal‐contraction‐crack networks as evidence for late‐Pleistocene permafrost in Inner Mongolia, China
Authors: Vandenberghe J. , Zhijiu Cui , Liang Zhao , Wei Zhang 
Published: April 2004

AbstractNumerous wedges on the Ordos Plateau show typical characteristics of periglacial sand wedges that enable them to be distinguished from desiccation cracks in clayey illuviation soil horizons. The sand wedges are organized in two generations of polygonal networks. The older generation is a large‐scale network with a diameter of 8 to 9 m and wedge depths up to more than 2 m. The younger generation has a mean diameter of 3 to 4 m and is formed within the large networks. It consists of shallow (0.6 to 1 m deep) but relatively wide wedges. In contrast to the typical sand wedges that form within continuous permafrost, the shallow wedges formed probably as ‘ground wedges’ by seasonal freezing. Ice wedges and cryoturbations developed only rarely, and exclusively in the most humid areas. Thermal‐contraction cracking occurred mainly between 26 and 20 ka BP, indicating mean annual temperatures at least 13°C lower than present. Before and after that period mean annual temperatures were at least 7 to 8.5° lower than today. The presence of these periglacial phenomena show that the southern limit of continuous permafrost in Inner Mongolia occurred south of 38°N during the Last Glacial Maximum. Copyright © 2004 John Wiley & Sons, Ltd.
The effect of different spray liquids on the foliar retention of agricultural sprays by wheat plants in a canopy
Authors: Butler Ellis M Clare , Webb Duncan A , Western Nigel M 
Published: April 2004

AbstractThe aim of this work was to examine the effect of liquid properties on spray retention in a range of situations representative of practical pesticide application. Liquids with different physical properties were sprayed with conventional flat‐fan and air‐induction nozzles onto outdoor‐grown wheat plants (Triticum aestivum L cv Axona) at growth stages between GS 22 and GS 35. Since total retention is affected by leaf surface as well as plant growth stage and canopy density, the experiments included spraying both single leaves and groups of plants with different canopy densities. Retention on whole plants was strongly influenced by plant growth and canopy properties. Individual leaf surfaces were not as water‐repellent as was found previously for younger indoor‐grown plants, reducing the effect of dynamic surface tension on retention. This, combined with the increased probability of droplets hitting foliage in a denser canopy, gave reduced differences in retention between liquids when compared with similar measurements made previously on younger plants. With a leaf area index greater than 7, retention on whole plants was almost independent of liquid. Air‐induction nozzles gave lower levels of retention than flat‐fan nozzles, with this difference greatest when spraying high dynamic surface tension liquids and at low crop densities. Copyright © 2004 Society of Chemical Industry
Arme Alte? Das Risiko von Altersarmut in Deutschland
Authors: Fasshauer Stephan 
Published: April 2004

AbstractDie Reform der Alterssicherung steht aktuell wieder im Blickpunkt des öffentlichen und politischen Interesses. Die demografische Entwicklung, die Veränderungen in der Arbeitswelt mit einer Zunahme von unsteten Erwerbsbiographien sowie der gesellschaftliche Wandel und das neue Rollenverständnis von Mann und Frau sind nur einige Stichworte, die diese Reformentwicklung und die Herausforderungen der Alterssicherung kennzeichnen. Um diesen Entwicklungen gerecht zu werden, wird es durch die Verabschiedung des so genannten „Nachhaltigkeitsgesetzes”︁ zu weiteren Leistungseinschnitten bei der gesetzlichen Rentenversicherung zu Gunsten eines stabilen Beitragssatzes kommen. Mit der erneuten Reduzierung des Leistungsniveaus der staatlichen Alterssicherung stellt sich zunehmend die Frage, in welchem Umfang die gesetzliche Rentenversicherung noch zur Sicherung des Lebensstandards beitragen kann. Je geringer das Leistungsniveau wird, desto drängender stellt sich die Frage nach dem Risiko von Altersarmut. Im Folgenden wird zunächst der aktuelle Status dieses Risikos anhand von Kennzahlen abgeschätzt. Im Anschluss werden die wesentlichen Einflussfaktoren der zukünftigen Risiko‐Entwicklung betrachtet.
Improvement of performance to discriminate malignant tumors from normal tissue on mammograms by feature selection and evaluation of feature selection criteria
Authors: Furuya Sachiko , Wei Jun , Hagihara Yoshihiro , Shimizu Akinobu , Kobatake Hidefumi , Nawano Shigeru 
Published: April 2004

AbstractThis paper reports the results of improving the performance of a previous system for discriminating malignant tumors by selecting a small number of features effective for discriminating malignant tumors from normal tissue on mammograms from 39 features. Specifically, the efficacy of the new system is evaluated by comparing the results with the case of using the previous 9 features. The paper also reports on the results of comparing the areas Az under ROC curves using Mahalanobis distance ratios, the areas Az under ROC curves based on the maximum likelihood method, and the average recognition rates based on the nearest‐neighbor decision rule. © 2004 Wiley Periodicals, Inc. Syst Comp Jpn, 35(7): 72–84, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10587
Quantitative study of aluminum‐induced changes in synaptic ultrastructure in rats
Authors: Jing Yuhong , Wang Ziren , Song Yanfeng 
Published: April 2004

AbstractSome evidence suggests that aluminum is one of the risk factors in Alzheimer's disease (AD); however, there is no study on the relationship between the synaptic configuration changes and aluminum uptake. In the present study, 40 rats were fed with water solution aluminum for 3 months and the effects of aluminum on the Gray's type I synapses in hippocampus and frontal cortex of rats were quantitatively investigated by electron microscopy. The effects of aluminum on the ability to learn and memorize were tested by a Morris water maze. Length of synaptic active zone, width of synaptic cleft, curvature of synapse, and thickness of postsynaptic density (PSD) were measured in the interface of synapses by the IBM‐PC microimage processing system. The flat synapse, positive and negative curvature synapses, as well as the perforated synapse were classified and counted according to the type of the interfacial structure of a synapse. The amounts of aluminum deposited in brain were measured with an atomic absorption spectrophotometer. Our results show that the time and the distance taken by the rats to find the water maze increased after the rats were fed aluminum for 3 months. As compared with control, the synapses in aluminum‐induced rats exhibited the following significant changes: decreased thickness of PSD (P < 0.01), increased width of synaptic cleft (P < 0.05), increased numbers of flat synapse, decreased numbers of positive curvature synapse and perforated synapse, and significantly increased aluminum deposits in hippocampus and frontal cortex (P < 0.01). Our study indicates that aluminum can decrease the ability of rats to learn and memorize and induce their synaptic configuration changes. These changes may be related to synaptic efficacy and may be one of the mechanisms for AL to induce AD. Synapse 52:292–298, 2004. © 2004 Wiley‐Liss, Inc.
Visceral pain: gender differences in response to experimental and clinical pain
Authors: Arendt‐Nielsen Lars , Bajaj Priti , Drewes Asbjørn Mohr 
Published: April 2004

AbstractGender differences in response to visceral pain have important implications for experimental studies and when evaluating clinical pain. Few studies have in details explored specific gender differences in response to experimental stimulation of selected visceral organs or specific visceral diseases. Lower pain threshold to e.g. oesophageal distension has however been shown in females. The effect of female sex hormones on visceral function and pain is studied in greater details in both experimental and clinical studies. Pronounced differences in pain sensitivity are found across the menstrual phases. This may also interact with pharmacological interventions. For clinicians assessing the pain level of female patients in the reproductive age group should take into consideration the physiological and clinical effects of the menstrual cycle and the somatic segmental sites related to the uterus and cervix when clinically evaluating the pain and assessing for disease activity.
Infections after Endoscopic Polypectomy Using Nasal Steroids
Authors: Bross‐Soriano Daniel , Arrieta‐Gómez Jose R. , Prado‐Calleros Héctor 
Published: April 2004

BACKGROUNDTopical nasal steroids such as beclomethasone dipropionate and fluticasone propionate have been widely used in the treatment of rhinitis and polyposis. An increase in infection has occurred with the use of fluticasone propionate after endoscopic polypectomy.OBJECTIVEThe purpose of this study was to determine the prevalence of nasal and paranasal infections with the use of topic nasal steroids after endoscopic polypectomy and to compare the recurrence rates of the polyposis.DESIGN AND SETTINGWe conducted a prospective, comparative, open, experimental, longitudinal study at an academic tertiary referral medical center.METHODSOne hundred sixty‐two patients in whom endoscopic polypectomy had been indicated were randomly divided into 3 groups of 54 patients each. The patients from the first group were treated with saline lavage only. Patients from the second group also received fluticasone propionate 400 μg/day in nasal spray after lavage. Patients from the third group received beclomethasone dipropionate 600 μg/day after lavage. The prevalence of infections and recurrence of polyposis was compared in the 3 groups.RESULTSThree patients, 2 in the placebo group and 1 in the beclomethasone group, developed infections during the first 3 months after surgical procedure. The recurrence of polyps in the group without steroids was 44%. In contrast, 15% from the patients treated with fluticasone showed recurrence of polyposis; furthermore, 26% of the patients treated with beclomethasone showed recurrence of polypsosis, with a minimum follow‐up of 12 months.CONCLUSIONSThe use of nasal steroids does not seem to increase the prevalence of infections after endoscopic polypectomy. (Otolaryngol Head Neck Surg 2004;130:319–22.)
Radiofrequency Treatment of Turbinate Hypertrophy: A Randomized, Blinded, Placebo‐Controlled Clinical Trial
Authors: Nease Carey J. , Krempl Greg A. 
Published: April 2004

OBJECTIVESWe sought to evaluate the short‐term efficacy of radiofrequency volumetric tissue reduction (RFVTR) in treating nasal obstruction in subjects with inferior turbinate hypertrophy.STUDY DESIGN AND SETTINGWe conducted a prospective, randomized, single‐blinded, placebo‐controlled trial with crossover option, involving 32 patients and performed in a clinical office setting at the University of Oklahoma Medical Center.RESULTSThe outcomes were measured using 10‐cm visual analog scales (VASs) before treatment and at 8 weeks and 6 months posttreatment. Improvement was shown in frequency of obstruction, severity of obstruction, and overall ability to breathe for both the placebo and RFVTR treatment arms at 8 weeks (P < 0.05). The amount of improvement, however, was significantly better in the treatment arm compared with placebo for the severity of obstruction and overall ability‐to‐breathe categories. At 6 months, the mean improvement scores were significantly better than the pretreatment scores for all 3 categories.CONCLUSIONSRFVTR is an effective alternative for the treatment of patients with nasal obstruction due to inferior turbinate hypertrophy.SIGNIFICANCEThis is the first randomized trial that demonstrates that RFVTR is significantly better than placebo in treating nasal obstruction due to inferior turbinate hypertrophy. (Otolaryngol Head Neck Surg 2004;130:291–9.)
Revision Endoscopic Frontal Sinus Surgery with Surgical Navigation
Authors: Chiu Alexander G. , Vaughan Winston C. 
Published: April 2004

BACKGROUNDRevision surgery of the frontal sinus remains one of the most difficult operations for the endoscopic surgeon. Most agree that knowledge and recognition of its complex anatomy and sparing of frontal recess mucosa are keys to a successful operation. The use of surgical navigation systems may allow for more precise dissections and greater rates of frontal recess patency.METHODSRetrospective review of all patients undergoing revision endoscopic frontal sinus surgery with surgical navigation was performed with a minimum 24‐month follow‐up.RESULTSSixty‐seven patients underwent revision endoscopic frontal sinus surgery with surgical navigation. The average follow‐up was 32 months. Fifty‐eight (86.6%) had a patent frontal recess and significant subjective improvement in symptoms. No patient underwent external frontal sinus obliteration, and there were no major complications.CONCLUSIONSEndoscopic techniques with surgical navigation are effective in revision frontal sinus cases. The dissection of remnant agger nasi, obstructing frontal and supraorbital cells are necessary to widen the anterior‐posterior as well as the medial‐lateral dimensions of the recess. Computer navigational systems appear to serve as a valuable adjunct in preoperative planning and safe intraoperative dissection. (Otolaryngol Head Neck Surg 2004;130:312–8.)
Imaging the Internal Structure of the Rat Cochlea Using Optical Coherence Tomography at 0.827 μm and 1.3 μm
Authors: Wong Brian J. F. , Zhao Yonghua , Yamaguchi Mark , Nassif Nader , Chen Zhongping , De Boer Johannes F. 
Published: April 2004

OBJECTIVEThe purpose of this study was to use high‐speed optical coherence tomography (OCT) to obtain cross‐sectional images of the rat cochlea.STUDY DESIGN AND METHODSThe cochleae of Sprague‐ Dawley rats were imaged within 2 to 4 hours after death. Specimens were prepared by removing the bulla to expose the mesotympanum; some images were obtained in intact temporal bones removed from the cranium. The central element of an OCT imaging device is a Michelson interferometer combined with a low‐coherence light source. This study used 2 OCT systems with different light sources: 1) a semiconductor optical amplifier operating and 2) a superluminescent diode with peak emissions wavelengths of 1.3 μm and 827 nm, respectively. Images (1.87 × 2.00 mm or 1.87 × 1.00 mm, 10 × 10 μm pixel resolution) were acquired at a frame rate of 1 Hz. Cross‐sectional images at 100‐μm increments were obtained from a medial‐to‐lateral direction.RESULTSThe scala vestibuli, scala media, scala tympani, modiolus, spiral ligament, and several turns of the cochlea were identified.CONCLUSIONThese images reflect the ability of OCT to provide images of the internal cochlea structure with micron scale resolution and at near‐real time frame rates. (Otolaryngol Head Neck Surg 2004;130:334–38.)
Patterns of Mold Sensitivity in the Subtropical Gulf Coast
Authors: Calhoun Karen H. 
Published: April 2004

OBJECTIVESWe sought to determine the patterns of mold‐ and nonmold positive skin tests in a subtropical Gulf Coast climate and to determine whether any particular positive skin tests predict “allergic versus nonallergic” status as shown on the full panel of skin testing.STUDY DESIGN AND SETTINGWe conducted a retrospective evaluation of serial endpoint allergy skin test results in 75 consecutive patients from a tertiary referral medical center.RESULTSOf the 67 evaluable patients, 58 (86.6%) had a positive skin test to at least 1 antigen. The most common positive skin tests were in response to cockroach, Dermatophygoides farinae, Bermuda grass, false ragweed, mesquite, Stemphylium, Curvularia, short ragweed, and Timothy grass. There were no identifiable groups of antigens that tended to occur together. Screening with a panel of 6 antigens (cockroach, dust mite, cat, rough marsh elder, Timothy grass, and Stemphylium) would have correctly predicted whether the patient would react to any or none of the full panel of antigens.CONCLUSIONCockroach, dust mite, and a grass were the most common positive skin tests among our patients, with many patients also having positive skin tests to molds. Although there is evidence that cross‐reactivity exists among different mold species, we were unable to identify any clusters of mold reacting together in individual patients. In our patient population, a 6‐allergen screening panel (cockroach, dust mite, cat, rough marsh elder, Timothy grass, and Stemphylium) would have accurately distinguished “allergic” from “nonallergic” patients, as demonstrated on the full panel of skin testing.SIGNIFICANCEA small (6‐antigen) screening panel accurately predicted “allergic” versus “nonallergic” as shown by our full panel of skin testing. This is useful clinically when an “allergic versus nonallergic” etiology of sinonasal symptoms affects treatment choices. (Otolaryngol Head Neck Surg 2004; 130:306–11.)