bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spintronics in metallic superconductor/ferromagnet hybrid structures
Authors: Sürgers Christoph , Singh Ajay , Stokmaier Markus , Goll Gernot , Pérez-Willard Fabian , Löhneysen Hilbert v. 
Published: February 2010

Abstract
Metallic hybrid structures comprizing superconducting and ferromagnetic materials are interesting objects for studying the mutual influence between superconductivity and ferromagnetic order. We focus on two particular systems that have been studied during the last few years. In superconducting spin-valves the transition temperature of a superconductor squeezed between two ferromagnetic layers depends on the relative orientation of the two magnetization directions. Results have been obtained for systems with in-plane and out-of-plane magnetizations. Furthermore, we report on the electronic transport through superconductor/ferromagnet nanocontacts that allow a determination of the current spin-polarization which is related to the bulk spin polarization.
Materials in optical data storage
Authors: Bruder Friedrich , Fäcke Thomas 
Published: February 2010

Abstract
Optical Data Storage has become the mainstream technology for distributing audio, video and computer software content as well as recording and archiving personal data during the past two and a half decades. The continuous demand for ever higher storage capacities and faster data transfer rates has led to the development of three disc format families Compact Discs, Digital Versatile Discs and Blu-ray Disc, which have become established in the market. Research and development for future high density formats exploits the already well established “bit-wise” recording and volume storage approaches like holographic and “page-wise” recording. Each existing and future technology imposes specific requirements on materials that can facilitate functioning and reliable products for the consumer. In this review several aspects of the interrelation between technological requirements and materials are highlighted.
Graphene metrology and devices
Authors: Diebold Alain C. , Nelson Florence 
Published: February 2010

Abstract
The unusual electronic properties of graphene make it a prime candidate material for extending nanoelectronics and designing new types of switches. Graphene's unusual properties are a result of the unusual band structure associated with the hexagonal bonding pattern and the electron/hole transport through the pi orbitals. Graphene samples are frequently more than one layer, or few-layer graphene, and the change in electronic properties with each layer depends on the stacking configuration and the rotational misorientation between the layers. Transport measurements of single layer graphene (SLG) show that graphene exhibits the quantum Hall effect. In addition, Berry Phase corrections to carrier transport measurements are now widely recognized. Because graphene is a single layer of carbon atoms, it is difficult to find, manipulate, and measure. We review the status of physical and electrical characterization of graphene and discuss the remaining challenges. We discuss results from optical microscopy, transmission electron microscopy, low energy electron microscopy, nano-Raman, and several scanned probe methods. Issues such as determination of the number of layers of graphene and rotational stacking misorientation are emphasized.
Dependence of optical, structural and electrical properties of Zn
x
Cd1–x
S thin films prepared by co-evaporation on the composition for x = 0 – 1
Authors: Zia Rehana , Saleemi Farhat , Naseem Shahzad 
Published: February 2010

Abstract
Thin films of zinc cadmium sulphide – a ternary compound intended to be used in solar cells – are prepared by co-evaporation. The films are prepared at room temperature, in a vacuum better than 10–5 Torr. The composition of these films is varied from x = 0 to x = 1 in the compound Zn
x
Cd1–x
S. The structural, optical and electrical properties have been investigated as a function of x. The direct band gap varies from 2.415 eV to 3.41 eV for x = 0 to x = 1 respectively. The crystal structure is found to be hexagonal (Wurtzite) for 0 ≤ x ≤ 0.8 and cubic zinc-blende for x > 0.8. The lattice constants decrease and the optical bandgap increases with the increase in the value of x. The resistivity of the Zn
x
Cd1–x
S films is found to decrease from 3.6 × 104 Ω cm for x = 0 to 69.5 Ω cm for x = 0.3 and again increases beyond this range to a value of 6.3 × 103 Ω cm for x = 1.0.
Characterisation of lead – calcium alloys ageing in anisothermal conditions by calorimetric, resistance and hardness in-situ measurements
Authors: Rossi F. , Lambertin M. , Delfaut-Durut L. , Maitre A. , Vilasi M. 
Published: February 2010

Abstract
Transformations undergone by lead – calcium alloys are numerous and have different kinetics from a few minutes to a few years. Anisothermal calorimetric measurements were performed to be able to identify these transformations quickly. It was then possible to identify five transformations. Complementary measurements have enabled us to define transformations with an in-situ electrical resistance measurement to follow the evolution of the calcium in solid solution and with an in-situ hardness measurement to characterise the mechanical properties. The aim of these results is to simulate the ageing and overageing of the alloy in isothermal conditions.
The oxidation behaviour of the 9 % Cr steel P92in CO2- and H2O-rich gases relevant to oxyfuel environments
Authors: Abellán Javier Pirón , Olszewski Tomasz , Meier Gerald H. , Singheiser Lorenz , Quadakkers Willem J. 
Published: February 2010

Abstract
In oxyfuel plants metallic heat exchanging components will be subjected to service environments containing high amounts of CO2 and water vapour. In the present paper, the oxidation behaviour of the ferritic/martensitic 9 % Cr steel P92 was studied in a model gas mixture containing 70 % CO2-30 % H2O in the temperature range 550 – 650 °C. The results were compared with the behaviour in air, Ar–CO2 and Ar–H2O. In the CO2- and/or H2O-rich gases, the steel formed iron-rich oxide scales which possess substantially higher growth rates than the Cr-rich surface scales formed during air exposure. The iron-rich oxide scales are formed as a result of a decreased flux of chromium in the bulk alloy toward the surface. This is the result of enhanced internal oxidation of chromium in the H2O-containing gases and carburisation in the CO2 gases. The oxide scales allow molecular transport of CO2 towards the metallic surface, resulting in carburisation of the alloy. The presence of water vapour induced buckling in the outer haematite layer, apparently as a result of compressive oxide growth stresses. Buckling did not occur in the H2O-free gas. This has been discussed in terms of the potential for H2O to increase growth stresses and accelerate crack propagation. The oxidation rates in CO2–H2O do not seem to be higher than those observed in flue gases of conventional fossil fuel fired power plants.
Ni2O3-modified TiO2 – xNx as efficientvisible-light photocatalysts
Authors: Wang Guiqiang , Li Yinmin , Zhuo Shuping 
Published: February 2010

Abstract
Ni2O3-modified TiO2 – xNx visible-light photocatalysts have been prepared by the sol-gel method followed by calcining at 450 °C. The photocatalysts were characterized using scanning electron microscopy, thermogravimetry-differential thermal analysis, X-ray diffraction, Fourier transform infrared and X-ray photoelectron spectroscopy. The visible-light photocatalytic activity of the samples was evaluated by decomposition of methylene blue in air under visible-light irradiation (λ > 420 nm). Results revealed that the Ni2O3-modified TiO2 – xNx samples exhibited irregular particle shapes. The crystal phase of Ni2O3-modified TiO2 – xNx samples was anatase. Compared with pure TiO2, the absorption of the Ni2O3-modified TiO2 – xNx samples extends significantly into the visible regions due to the doped N atom in the interstitial sites of the TiO2 lattice. The visible-light photocatalytic activity of Ni2O3-modified TiO2 – xNx samples was improved greatly since the loaded Ni2O3 can facilitate charge transfer.
Structure and mechanical properties of an AlCr6Fe2Ti1 alloy produced by rapid solidification powder metallurgy method
Authors: Michalcová Alena , Vojtěch Dalibor , Novák Pavel , Šittner Petr , Pilch Jan , Drahokoupil Jan , Kolařík Kamil 
Published: February 2010

Abstract
In the present paper, the structure and properties of a Al–Cr–Fe–Ti alloy produced by powder metallurgy are described. An initial rapidly solidified powder alloy was prepared by the pressure nitrogen melt atomisation. Subsequently, the granulometric powder fraction of less than 45 μm was hot-extruded. According to X-ray diffraction and transmission electron microscopy observation, the compact material is composed of α-Al grains and spheroids of intermetallic phases. The α-Al grains of the compacted material are recrystallized and neither residual stress nor texture were observed. The values of ultimate tensile strength and yield strength of the investigated material were similar to the values for conventional Al-based alloys. Dependences of ultimate tensile strength and yield strength on temperature were also measured. Excellent thermal stability of the powder metallurgy produced Al–Cr-based material was proven by room-temperature hardness measurement after long-term annealing at elevated temperature.
The role of defects in resistively switching chalcogenides
Authors: Waser Rainer , Dittmann Regina , Salinga Martin , Wuttig Matthias 
Published: February 2010

Abstract
This overview describes the present understanding of resistive switching phenomena encountered in chalcogenide-based cells which may be utilized in energy-efficient non-volatile memory devices and in array-based logic applications. We introduce the basic operation principle of the phase change mechanism, the thermochemical mechanism, and the valence change mechanism and we discuss the crucial role of structural defects in the switching processes. We show how this role is determined by the atomic structure of the defects, the electronic defect states, and/or the ion transport properties of the defects. The electronic structure of the systems in different resistance states is described in the light of the chemical bonds involved. While for phase change alloys the interplay of ionicity and hybridization in the crystalline and in the amorphous phase determine the resistances, the local redox reaction at the site of extended defects, the change in the oxygen stoichiometry, and the resulting change in the occupancy of relevant orbitals play the major role in transition metal oxides which switch by the thermochemical and the valence change mechanism. Phase transformations are not only discussed for phase change alloys but also for redox-related switching processes. The switching kinetics as well as the ultimate scalability of switching cells are related to structural defects in the materials.
Comparison of percutaneous balloon compression and glycerol rhizotomy for the treatment of trigeminal neuralgia
Authors: Kouzounias Konstantinos , Lind Göran , Schechtmann Gastón , Winter Jaleh , Linderoth Bengt 
Published: February 2010

Object
The aim of this study was to compare percutaneous balloon compression (PBC) and percutaneous retrogasserian glycerol rhizotomy (PRGR) in terms of effectiveness, complications, and technical aspects.

Methods
Sixty-six consecutive PBC procedures were performed in 45 patients between January 2004 and December 2008, and 120 PRGR attempts were performed in 101 patients between January 2006 and December 2008. The PRGR procedures were not completed due to technical reasons in 19 cases. Five patients in the Balloon Compression Group and 9 patients in the Glycerol Group were lost to follow-up and were excluded from the study. The medical records and the intraoperative fluoroscopic images from the remaining cases were retrospectively examined, and the follow-up was completed with telephone contact, when necessary. The 2 groups were compared in terms of initial effect, duration of effect, and rates of complications as well as severity and type of complications.

Results
The rates for immediate pain relief were 87% for patients treated with glycerol injection and 85% for patients treated with balloon compression. The Kaplan-Meier plots for the 2 treatment modalities were similar. The 50% recurrence time was 21 months for the balloon procedure and 16 months for the glycerol procedure. When the groups were broken down by the “previous operations” criterion, the 50% recurrence time was 24 months for the Glycerol First Procedure Group, 6 months for the Balloon First Procedure Group, 8 months for the Glycerol Previous Procedures Group, and 21 months for the Balloon Previous Procedures Group. The rates of complications (excluding numbness) were 11% for PRGR and 23% for PBC, and this difference was statistically significant (chi-square test, p = 0.04).

Conclusions
Both PRGR and PBC are effective techniques for the treatment of trigeminal neuralgia, with PRGR presenting some advantages in terms of milder and fewer complications and allowing lighter anesthesia without compromise of analgesia. For these reasons the authors consider PRGR as the first option for the treatment of trigeminal neuralgia in patients who are not suitable candidates or are not willing to undergo microvascular decompression, while PBC is reserved for patients in whom the effect of PRGR has proven to be short or difficult to repeat due to cisternal fibrosis.
Effects of magnetic resonance imaging in patients with implanted deep brain stimulation systems
Authors: Fraix Valerie , Chabardes Stephan , Krainik Alexandre , Seigneuret Eric , Grand Sylvie , Le Bas Jean-François , Krack Paul , Benabid Alim-Louis , Pollak Pierre 
Published: February 2010

Object
The aim of this study was to study the effects of MR imaging on the electrical settings of deep brain stimulation (DBS) systems and their clinical consequences.

Methods
The authors studied the effects of 1.5-T MR imaging on the electrical settings of implanted DBS systems, including 1 or more monopolar or quadripolar leads, extension leads, and single- or dual-channel implantable pulse generators (IPGs). The IPG was switched off during the procedure and the voltage was set to 0. The impedances were checked before and after MR imaging.

Results
Five hundred seventy patients were treated with DBS for movement disorders and underwent brain MR imaging after lead implantation and before IPG implantation. None of the patients experienced any adverse events. Thirty-one of these patients underwent 61 additional MR imaging sessions after the entire DBS system had been implanted. The authors report neither local cutaneous nor neurological disorders during or after the MR imaging session. No change in the IPG settings occurred when the magnet reed switch function remained disabled during the procedure.

Conclusions
This study demonstrates that 1.5-T MR imaging can be performed safely with continuous monitoring in patients with a DBS system. The ability to disable the magnet reed switch function of the IPG prevents any change in the electrical settings and thus any side effects. The increasing number of DBS indications and the widespread use of MR imaging indicates the need for defining safety guidelines for the use of MR imaging in patients with implanted neurostimulators.
Measuring joint involvement in polyarticular psoriatic arthritis: An introduction of alternatives
Authors: Englbrecht M. , Wang Y. , Ronneberger M. , Manger B. , Vastesaeger N. , Veale D. J. , Schett G. 
Published: February 2010

AbstractObjectiveTo compare the reliability of 3 different simplified joint counts with the gold standard 66 swollen/68 tender joint count (JC66/68) for assessing clinical response in patients with polyarticular psoriatic arthritis (PsA).MethodsThe 28–joint count (JC28), in the same way that it is used in rheumatoid arthritis, and 2 measures including distal interphalangeal (DIP) joints (the 32–joint count [JC32], including all finger joints as well as wrists and knees, and 36–joint count [JC36], which additionally included elbows and ankles), were compared with the JC66/68 in 182 patients using data from the Infliximab Multinational Psoriatic Arthritis Controlled Trial 2 trial database. Pearson's correlation coefficients were calculated to compare the swollen and tender JC28, JC32, and JC36 with the corresponding results of the total JC66/68. American College of Rheumatology (ACR) responses based on the individual measures were compared, and their ability in predicting a clinical response of ACR 20% improvement (ACR20) based on the JC66/68 was assessed by calculating the area under the receiver operating characteristic curve via logistic regression and the maximum Youden indices at weeks 14 and 24.ResultsAll simplified joint counts were highly correlated to the standard JC66/68 both for tenderness and swelling at each individual visit (Pearson's correlation coefficients consistently >0.8, n = 182–200; P < 0.0001). Logistic regression for ACR20 response showed that area under the curve was constantly >0.91, with comparable results for Youden indices of the simplified joint counts.ConclusionAll simplified joint counts considered seemed sufficiently sensitive and specific to measure clinical response in trial patients with polyarticular PsA when compared with the JC66/68, no matter whether DIP joints were included (the JC36 and JC32) or excluded (the JC28). Further research will be needed to clarify this issue.
Night pain in hip and knee osteoarthritis: A focus group study
Authors: Woolhead Gillian , Gooberman‐Hill Rachael , Dieppe Paul , Hawker Gillian 
Published: February 2010

AbstractObjectiveTo explore the experience of night pain in people with hip or knee osteoarthritis (OA).MethodsTwenty‐eight focus groups were conducted in 6 centers in 4 countries, with a total of 130 men and women with hip or knee OA. Two focus groups were excluded from the analysis, leaving 26 groups comprising 123 participants. Sampling was performed to ensure approximately equal representation of individuals with mild, moderate, and severe pain, hip OA, and knee OA. Format and methodology were standardized across centers, and participants described and discussed their experience of night pain. The focus groups were audio‐recorded and transcribed. Data were analyzed by identifying emergent codes that were grouped and compared, resulting in the identification of key themes.ResultsThe majority of participants (81%) experienced night pain; the remaining 19%, who reported no night pain, were from the moderate or severe pain focus groups. Similar night pain experiences were expressed by the hip and knee OA participants. Night pain was also present regardless of the stage of OA, but severity increased as the disease progressed. Night pain was variable and intermittent. Three key themes were identified: prediction of night pain, sleep disturbance, and adaptations and treatment regimens.ConclusionDue to its variability and complexity, the assessment of night pain should take into account the importance of the patient narrative. Also, night pain may not be a distinct marker of disease severity, and this may have implications for its use as a priority indicator for total joint replacement.
Effects of common footwear on joint loading in osteoarthritis of the knee
Authors: Shakoor Najia , Sengupta Mondira , Foucher Kharma C. , Wimmer Markus A. , Fogg Louis F. , Block Joel A. 
Published: February 2010

AbstractObjectiveElevated joint loads during walking have been associated with the severity and progression of osteoarthritis (OA) of the knee. Footwear may have the potential to alter these loads. This study compares the effects of several common shoe types on knee loading in subjects with OA of the knee.MethodsThirty‐one subjects (10 men, 21 women) with radiographic and symptomatic knee OA underwent gait analyses using an optoelectronic camera system and multicomponent force plate. In each case, gait was evaluated during barefoot walking and while wearing 4 different shoe types: 1) clogs, 2) stability shoes, 3) flat walking shoes, and 4) flip‐flops. Peak knee loads were compared between the different footwear conditions.ResultsOverall, the clogs and stability shoes resulted in a significantly higher (∼15% higher) peak knee adduction moment (mean ± SD 3.1 ± 0.7 and 3.0 ± 0.7 divided by body weight [BW] × height [H] multiplied by 100, respectively; P < 0.05) compared with that of flat walking shoes (mean ± SD 2.8 ± 0.7 %BW × H), flip‐flops (mean ± SD 2.7 ± 0.8 %BW × H), and barefoot walking (mean ± SD 2.7 ± 0.7 %BW × H). There were no statistically significant differences in knee loads with the flat walking shoes and flip‐flops compared with barefoot walking.ConclusionThese data confirm that footwear may have significant effects on knee loads during walking in subjects with OA of the knee. Flexibility and heel height may be important differentiating characteristics of shoes that affect knee loads. In light of the strong relationship between knee loading and OA, the design and biomechanical effects of modern footwear should be more closely evaluated in terms of their effects on the disease.
The independent effect of pain in one versus two knees on the presence of low physical function in a multicenter knee osteoarthritis study
Authors: White Daniel K. , Zhang Yuqing , Felson David T. , Niu Jingbo , Keysor Julie J. , Nevitt Michael C. , Lewis Cora E. , Torner James C. , Neogi Tuhina 
Published: February 2010

AbstractObjectiveAlthough knee pain severity is thought to greatly impact function, the additional contribution of pain in 1 versus 2 knees is not known. We examined the relationship between unilateral versus bilateral pain with low physical functioning at baseline and 30 months while accounting for knee pain severity.MethodsThe Multicenter Osteoarthritis Study is a cohort study of people who have or are at high risk for knee osteoarthritis. We defined low physical function as Western Ontario and McMaster Universities Osteoarthritis Index physical functioning scores ≥28 of 68, consistent with poor functional outcome. Incidence and improvement from low physical function were defined as scores that declined below and improved above this threshold at 30 months. We examined the association between pain in 1 or 2 knees with low physical function with risk ratios (RRs) adjusting for known confounders.ResultsOf the 2,069 subjects (mean ± SD age 63 ± 8 years, mean ± SD body mass index 31 ± 6 kg/m2, 63% women), the prevalence of low physical functioning was 50% lower among persons with unilateral pain compared with those with bilateral pain (adjusted prevalence ratio 0.5 [95% confidence interval (95% CI) 0.3–0.7]). Of those without low physical functioning at baseline, the risk of incidence at 30 months was 30% less for unilateral compared with bilateral pain (adjusted RR 0.7 [95% CI 0.5–1.0]). Of those with low physical functioning at baseline, improvement was 1.7 times more likely for those with unilateral compared with bilateral pain (adjusted RR 1.7 [95% CI 1.3–2.2]).ConclusionThe presence of pain in 1 versus 2 knees provides important information regarding present and future physical functioning.