bluuebunny/crossref_metadata_2025_split huggingface dataset:
GC‐MS analysis of organic compounds in wastewater and sewage sludge
Authors: Ligon Axel Patrick , Zuehlke Sebastian , Spiteller Michael 
Published: December 2007

AbstractA multimethod based on liquid–liquid extraction and solid–liquid extraction for the analysis of persistent organic pollutants in water and sludge from sewage treatment plants has been established. Traces of 22 organic compounds used in industry and personal care products (PCPs) were analyzed by GC/MS. The LODs for the analytes were less than 2.3 ng/L for wastewater and 31 μg/kg (dry weight matter) for sewage sludge. Satisfactory recoveries (70–130%) were achieved. The validated method permits the analysis of water and sludge samples at various stages of the treatment from different sewage treatment plants. Thus, the distribution between water and sludge as well as the dissipation of the compounds analyzed were balanced. By this means, the efficiency of different wastewater treatment plants (WWTPs) can be evaluated and measures can be taken to optimize the treatment process at different stages.
Inverse scattering for planar cracks via nonlinear integral equations
Authors: Ivanyshyn O. , Kress R. 
Published: December 2007

AbstractWe present a Newton‐type method for reconstructing planar sound‐soft or perfectly conducting cracks from far‐field measurements for one time‐harmonic scattering with plane wave incidence. Our approach arises from a method suggested by Kress and Rundell (Inv. Probl. 2005; 21(4):1207–1223) for an inverse boundary value problem for the Laplace equation. It was extended to inverse scattering problems for sound‐soft obstacles (Mathematical Methods in Scattering Theory and Biomedical Engineering. World Scientific: Singapore, 2006; 39–50) and for sound‐hard cracks (Inv. Probl. 2006; 22(6)). In both cases it was shown that the method gives accurate reconstructions with reasonable stability against noisy data. The approach is based on a pair of nonlinear and ill‐posed integral equations for the unknown boundary. The integral equations are solved by linearization, i.e. by regularized Newton iterations. Numerical reconstructions illustrate the feasibility of the method. Copyright © 2007 John Wiley & Sons, Ltd.
Does more solvent in bore liquid create more open inner surface in hollow fiber membranes?
Authors: Li Xue‐Mei , He Tao 
Published: December 2007

AbstractThe solvent content in the bore liquid controls the inner structure of a hollow fiber membrane. Based on the theory of liquid–liquid phase separation, at a higher solvent concentration, the inner surface is more open and the transport resistance is lower. However, the theory does not describe clearly the membrane structure formation at a very high solvent concentration. A logic deduction is that more solvent in the bore liquid results in more open inner structure. In this report, a polymer solution, polysulfone (PSf)/N‐methylpyrrolidone (NMP)/diethylene glycol (DegOH) was used to investigate the relationship between the membrane resistance and solvent content in the bore liquid. A triple orifice spinneret was used to prepare an open outer surface, minimizing the transport resistance in the membrane outer layer. Bore liquid solutions with NMP concentration close to the critical solvent concentration (CSC) were used. The membranes were characterized by scanning electron microscopy (SEM), pore size and pore size distribution, nitrogen and pure water permeability. The results indicated that at a concentration far below the CSC, a higher NMP content corresponds to a more open inner surface, but the aggressive addition of solvent to a concentration close to CSC tends to form closed cells; thus water and gas permeability significantly decreases. This phenomenon was explained by nuclei formation and growth, followed by the formation of a dense skin and closed cell structure in a mild coagulant. Copyright © 2007 John Wiley & Sons, Ltd.
Highly elevated ferritin levels and the diagnosis of hemophagocytic lymphohistiocytosis
Authors: Allen Carl E. , Yu Xiaoying , Kozinetz Claudia A. , McClain Kenneth L. 
Published: December 2007

AbstractBackgroundHemophagocytic lymphohistiocytosis (HLH) is a potentially lethal condition characterized by a pathologic inflammation. The diagnostic criteria for HLH include fever, splenomegaly, cytopenias, hypertriglyceridemia, hypofibrinogenemia, abnormal natural killer cell (NK cell) functional assay, elevated soluble IL‐2Rα level, and elevated ferritin level (>500 µg/L). Institution of timely therapy in these critically ill patients may be delayed by difficulties establishing the diagnosis. NK cell functional assay and soluble IL‐2Rα level may require send‐out to a specialized lab. However, ferritin level is available on a same‐day basis at most institutions. In this study, we examined the utility of quantitative ferritin levels in diagnosing HLH.ProcedureAll patients with ferritin values >500 µg/L obtained at Texas Children's Hospital between January 10, 2003 and January 10, 2005 were identified. Patient charts were reviewed for ferritin levels and hospital course.ResultsDuring the study interval, 330 patients had ferritin levels >500 µg/L. Ten of the 330 patients were diagnosed with HLH. A ferritin level over 10,000 µg/L was 90% sensitive and 96% specific for HLH. Another diagnostic category with significantly elevated ferritin level was illness of unknown cause (n = 10), and only two of these patients were fully evaluated for HLH.ConclusionsFerritin levels above 10,000 µg/L appear to be specific and sensitive for HLH. In patients without a significant medical history and a new onset of febrile illness with highly elevated ferritin levels, the diagnosis of HLH should be evaluated. Pediatr Blood Cancer 2008;50:1227–1235. © 2007 Wiley‐Liss, Inc.
The dipeptidyl‐peptidase‐4 (DPP‐4) inhibitors: a new class of oral therapy for patients with type 2 diabetes mellitus
Authors: Elrishi MA , Khunti K , Jarvis J , Davies MJ 
Published: December 2007

AbstractThe observation that an oral glucose load is more effective at releasing insulin, compared with the same amount of glucose given intravenously, has been called the incretin effect, and is due to the augmentation of glucose‐stimulated insulin secretion by intestinally derived peptides.Glucagon‐like peptide‐1 (GLP‐1), in particular, has been shown to stimulate insulin release in a glucose‐dependent manner in humans, but it is rapidly metabolised by dipeptidyl‐peptidase‐4 (DPP‐4). Inhibition of DPP‐4 activity enhances fasting and post‐prandial GLP‐1 which, in turn, improves glycaemic control by increasing glucose‐dependent insulin secretion and by decreasing glucagon concentration.Current oral antidiabetic drugs (OADs) for type 2 diabetes are limited by adverse effects such as gastrointestinal problems, weight gain, oedema, or hypoglycaemia. In addition, there are recent concerns about rosiglitazone and cardiovascular outcomes, and with the thiazolidinediones in general regarding excess fracture rate in women and increased risk of heart failure. Thus the introduction of a new class of OADs, the DPP‐4 inhibitors, is welcome.This review article discusses the most clinically relevant data published on DPP‐4 inhibitors based on Medline literature searches (1966 to August 2007) and posters and oral presentations from the American Diabetes Association Scientific Sessions in 2006 and 2007. We have concentrated our review on two DPP‐4 inhibitors: sitagliptin (Januvia) and vildagliptin (Galvus). Copyright © 2007 John Wiley & Sons.
Highly selective and rapid enrichment of phosphorylated peptides using gallium oxide‐coated magnetic microspheres for MALDI‐TOF‐MS and nano‐LC‐ESI‐MS/MS/MS analysis
Authors: Li Yan , Lin Huaqing , Deng Chunhui , Yang Pengyuan , Zhang Xiangmin 
Published: December 2007

AbstractIn this work, we present, to our knowledge, the first demonstration of the utility of iron oxide magnetic microspheres coated with gallium oxide for the highly selective enrichment of phosphopeptide prior to mass spectrometric analysis. These microspheres that we prepared not only have a shell of gallium oxide, giving them a high‐trapping capacity for the phosphopeptides, but also their magnetic property enables easy isolation by positioning an external magnetic field. Tryptic digest products of phosphoproteins including β‐casein, ovalbumin, casein, as well as five protein mixtures were used as the samples to exemplify the feasibility of this approach. In very short time (only 0.5 min), phosphopeptides sufficient for characterization by MALDI‐TOF‐MS were selectively enriched by the Ga2O3‐coated Fe3O4 microspheres. The performance of the Ga2O3‐coated Fe3O4 microspheres were further compared with Fe3+‐immobilized magnetic silica microspheres, commercial Fe3+‐IMAC resin, and TiO2 beads for enrichment of peptides originating from tryptic digestion of β‐casein and BSA with a molar ratio of 1:50, and the results proved a stronger selective ability of Ga2O3‐coated Fe3O4 microspheres over the other materials. Finally, the Ga2O3‐coated Fe3O4 microspheres were successfully utilized for enrichment of phosphopeptides from digestion products of rat liver extract. All results show that Ga2O3‐coated Fe3O4 microsphere is an effective material for selective isolation and concentration of phosphopeptides.
A new standardizexd treadmill walking test requiring low motor skills in children aged 4–10 years
Authors: Wäffler‐Kammermann Nathalie , Lacorcia Ruth Stauffer , Wettstein Markus , Radlinger Lorenz , Frey Urs 
Published: December 2007

AbstractExercise intolerance may be reported by parents of young children with respiratory diseases. There is, however, a lack of standardized exercise protocols which allow verification of these reports especially in younger children. Consequently the aims of this pilot study were to develop a standardized treadmill walking test for children aged 4–10 years demanding low sensorimotor skills and achieving high physical exhaustion. In a prospective experimental cross sectional pilot study, 33 healthy Caucasian children were separated into three groups: G1 (4–6 years, n = 10), G2 (7–8 years, n = 12), and G3 (9–10 years, n = 11). Children performed the treadmill walking test with increasing exercise levels up to peak condition with maximal exhaustion. Gas exchange, heart rate, and lactate were measured during the test, spirometry before and after. Parameters were statistically calculated at all exercise levels as well as at 2 and 4 mmol/L lactate level for group differences (Kruskal–Wallis H‐test, α = 0.05; post hoc: Mann–Whitney U‐test with Bonferroni correction α = 0.05/n) and test–retest differences (Wilcoxon‐rank‐sum test) with SPSS. The treadmill walking test could be demonstrated to be feasible with a good repeatability within groups for most of the parameters. All children achieved a high exhaustion level. At peak level under exhaustion condition only the absolute VO2 and VCO2 differed significantly between age groups. In conclusion this newly designed treadmill walking test indicates a good feasibility, safety, and repeatability. It suggests the potential usefulness of exercise capacity monitoring for children aged from early 4 to 10 years. Various applications and test modifications will be investigated in further studies. Pediatr Pulmonol. 2008; 43:187–195. © 2007 Wiley‐Liss, Inc.
Numerical simulation of spin accumulation and tunnel magnetoresistance in single electron tunnelling junctions with a nonmagnetic nanoparticle
Authors: Wang H. , Mitani S. , Takanashi K. , Imamura H. 
Published: December 2007

AbstractFor the device designs showing a large tunnel magnetoresistance (TMR) due to spin accumulation, spin dependent single electron tunnelling in double tunnel junctions with a nonmagnetic nanoparticle is investigated by numerical simulations in the sequential tunnelling regime. We show that the bias voltage dependecnce of TMR ratio takes a maximum value just above the Coulomb threshold voltage and the optimal junction parameters for a large TMR ratio are obtained. We also show that the maximum value of the TMR ratio almost agrees with 2P2/(1+P2) where P is the spin polarization of ferromagnetic electrodes. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spin accumulation and magnetoresistance of a CPP‐GMR system with a current confined path
Authors: Imamura Hiroshi 
Published: December 2007

AbstractWe theoretically studied the spin accumulation and magnetoresistance of the CPP‐GMR system with a current confined path (CCP) by starting with the Boltzmann equation. We numerically solved the continuity equations for charge and spin currents and showed that the MR ratio is enhanced for the system with a narrow contact. We discussed the origin why the MR ratio is enhanced due to the CPP structure. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nonequilibrium process of magnetization switching influenced by thermal spin fluctuations
Authors: Choi B. C. , Hong Y. K. , Rudge J. , Girgis E. , Kolthammer J. , Donohoe G. W. 
Published: December 2007

AbstractWe present a systematic study of the dynamic behavior of nonequilibrium magnetization configurations with time‐resolved scanning Kerr microscope and micromagnetic modeling. The magnetization switching dynamics enters a fully dynamic regime when the external field conditions are changed much faster than the magnetization in the elements is able to respond. We observe that the dynamic pathway develops a complexity not seen in quasi‐static reversal, but still retains a high level of order with well‐developed dynamic domain patterns formed in response to sub‐nanosecond transitions of the external applied magnetic field pulse. An increasing complexity in the spatial structure of the evolution is found to accompany the increasing switching speed, when a ferromagnetic element is driven by progressively faster reversing fields applied anti‐parallel to the initial magnetization direction. The sensitive dependence of the nonequilibrium magnetization configurations on switching speed can be understood in terms of a dynamic exchange interaction of thermally excited spins; the coherent modulation of the spins is strongly dependent on the rise time of switching magnetic field pulses. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mössbauer study of iron ordering in mixed valence system LuFe2O4
Authors: Bang Bong Kyu , Kim Sung Baek , Cheong S‐W. , Kim Chul Sung 
Published: December 2007

AbstractSingle crystalline LuFe2O4 was grown by the floating zone method. The crystallographic and magnetic properties of the sample were measured using x‐ray diffractometer (XRD), Mössbauer spectroscopy, and vibrating sample magnetometer (VSM). The crystal structure was found to be a two‐dimensional layered‐type rhombohedral with space group R3‐mh. The magnetic Curie temperature (TC) was determined to be 250 K from the M ‐T curve and Mössbauer spectra. Just below TC, the magnetic moment has large value and shows a abrupt change in M ‐T curve. The Mössbauer spectra have been taken at various temperatures ranging from 4.2 to 370 K. We confirmed that the charge ordering of Fe3+ and Fe2+ ions was begun below 350 K, magnetic superstructure of the different ionic state was formed around 320 K. The isomer shift value of Fe2+ doublet increases with decreasing temperature from 320 to 235 K. At low temperature, Mössbauer spectra consisted of four sextets with magnetic ordering. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Direct observation of saw‐tooth typed domain wall jumps in epitaxial ferromagnetic MnAs film on GaAs(001)
Authors: Ryu Kwang‐Su , Akinaga Hiro , Shin Sung‐Chul 
Published: December 2007

AbstractWe report the direct observation of saw‐tooth domain wall jumps in epitaxial ferromagnetic MnAs film on GaAs(001) via a magneto‐optical Kerr effect microscope. Interestingly, it is found that the saw‐tooth domain wall jumps are generated along an easy axis orientation and the saw‐tooth angle is nearly constant irrespective of the applied field direction. These observations can be understood on the basis of strong uniaxial anisotropy on the sample plane. The analytical study reveals that the saw‐tooth domain wall structure results from competition between the domain wall energy and the dipolar energy. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Domain wall pinning by alternating materials in current‐induced domain wall motion
Authors: Kim W. J. , Lee T. D. , Lee K. J. 
Published: December 2007

AbstractFor the application of current‐induced domain wall motion, the pinning position of a domain wall must be precisely defined with a low depinning current density. A conventional way of pinning a domain wall is to use a notch which is patterned on an edge of nanostrip. As an alternative scheme of domain wall pinning, we performed micromagnetic investigation of the current‐induced domain wall motion in a nanostrip with alternating materials. A segment with different magnetic parameters such as saturation magnetization, exchange constant or crystalline anisotropy can effectively pin a domain wall. It is because the segment acts as an energy barrier in the domain wall motion. Threshold current densities to depin the domain wall in nanostrips with alternating materials were of the order of 108 A/cm2, and can be modulated by changing the material parameters and the length of the segment. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Enhancement of ordering temperatures of La0.67Ca0.33MnO3 thin films by adding Ho atoms
Authors: Hsu Jen‐Hwa , Hung S. H. , Biswas Subhayan , Sharma Puneet , Lin J. G. 
Published: December 2007

AbstractA series of Hox‐La0.67Ca0.33MnO3 thin films with x = 0.0, 0.2, 04, 0.6, and 1.0 mol percent have been deposited on SrTiO3(100) substrates with the substrate temperature controlled at 600 oC by dc magnetron sputtering. The magnetic ordering (Tc) and metal‐insulator transition temperature (TMI) were enhanced about 25∼60 K for Hox‐La0.67Ca0.33MnO3 films. At x = 0.4 the ordering temperature has been increased above 280 K. The variation of the ordering temperature is simply ascribed to the presence of Ho. The results of magnetoresistance measurements indicated that the samples exhibited colossal magnetoresistance effect (CMR) and a maximum was observed at a temperature TP. It was noted that the variation of TP with x displayed the same trend as that of TMI. Although the CMR was suppressed with the addition of Ho, a sizeable CMR ≈ 20% was still detected at 270 K in the sample with 0.4 mol% Ho due to much higher TP. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetoresistance and Hall effect in spin‐polarized two‐dimensional electron gas with spin‐orbit interaction
Authors: Kato T. , Ishikawa Y. , Itoh H. , Inoue J. 
Published: December 2007

AbstractWe study the effect of disorder on the intrinsic anomalous Hall (AH) conductivity and anisotropic magnetoresistance (AMR) in a spin‐polarized two‐dimensional electron gas with a Rashba‐type spin‐orbit interaction. We find that both AH conductivity and AMR vanish unless the lifetime is spin‐dependent, similar to the spin Hall (SH) conductivity in the non‐magnetic system. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Depth sensitive exchange coupling in top and bottom pinned spin valve structures
Authors: Parvatheeswara Rao B. , Ananda Kumar S. , Noh Y. O. , Kim CheolGi 
Published: December 2007

AbstractTop and bottom pinned spin valve structures have been fabricated using rf magnetron sputtering to study the depth sensitive exchange coupling. M‐H curves of both the configurations in as‐deposited and annealed forms have been measured by vibration sample magnetometry (VSM) and transverse Kerr effect spectrometry (TKE) using DC and AC magnetic fields, respectively. The TKE signal was also examined as a function of wavelength in the range from 300‐800 nm, to obtain data from the full length of the bottom NiFe free layer covering either side of the interface. Annealing of the samples brings in higher values of exchange bias field compared to as‐deposited samples perhaps due to improved uniformity in exchange conditions. The TKE data at 500 nm wavelength point towards energetically favourable spin structure at the pinned interface. Wavelength dependence of the TKE data shows an anamolous trend close to the NiFe‐Cu (seed layer) inteface, which was attributed to a periodic Cu diffusion assisted non‐specular reflection (diffraction) component. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
55Mn NMR study of the A‐type antiferromagnetic and metallic manganites La1–xSrxMnO3 (0.5 ≤ x ≤ 0.6)
Authors: Shim Jung Hyun , Lee Soonchil , Dho Joonghoe 
Published: December 2007

AbstractThe microscopic magnetic and electronic properties of La1‐xSrxMnO3 (0.5 ≤ x ≤ 0.6) were investigated using 55Mn nuclear magnetic resonance (NMR). The NMR spectral intensity showed a large decrement as x increases above the boundary (x ∼ 0.52) of ferromagnetic (FM) and A‐type antiferromagnetic (AFM) phases. The spectrum of the samples shows a coexistence of two different phases, i.e., a metallic major phase and an insulating minor phase. The spin‐spin relaxation time strongly depends on the resonance frequency, indicating that the Shul‐Nakamura process by spin‐wave excitation is the dominant relaxation mechanism. This type of frequency dependence of the spin‐spin relaxation time was not observed in the CE‐type AFM manganite Nd0.5Sr0.5MnO3. The A‐type AFM spin structure and the Shul‐Nakamura relaxation process appears to be a unique characteristics of La1‐xSrxMnO3 (0.54 ≤ x ≤ 0.6) that is related to the 2D‐like spin coupling in a nearly tetragonal crystal structure. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Exchange bias and uncompensated spins in a Fe/Cr(100) bilayer
Authors: Kim Ki‐Yeon , Hwang Yo‐Sun , Park J.‐G. , Torikai N. , Takeda M. , Han S. W. , Shin Sung‐Chul 
Published: December 2007

AbstractWe have investigated the effect of the field cooling on the exchange bias and the coercivity in an exchange‐biased Fe/Cr(100) bilayer using SQUID magnetometer. After the field cooling, magnetization shifted upwards, indicative of surplus magnetic moments, which could be interpreted as an evidence of pinned and uncompensated Cr magnetic moments induced by the cooling field. Interestingly enough, we also discovered that not all the pinned and uncompensated spins seem to be involved in producing the exchange bias, although they contribute to increasing the coercivity and inducing the surplus magnetization. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of the nano‐oxide layer position on magnetoresistance ratio and magnetic properties in spin valves
Authors: Suh Jeong Dae , Ross C. A. 
Published: December 2007

AbstractWe have investigated the influence of nano‐oxide layer position on magnetoresistance of the NiFe/Cu/Co/Cu spin valves. We found that the giant magnetoresistance (GMR) ratio, magnetic coercivity and surface roughness were strongly dependent on the nano‐oxide layer positions. For nano‐oxide layer positions from the bottom to top part of spin valve, the GMR ratio varied from 2.8% to 0.15% depending on the position of the nano‐oxide layer within the spin valves. It was also found that the nano‐ oxide layer(NOL) position affect the surface roughness and magnetic coercivity significantly. Variation of the GMR ratio with nano‐oxide layer position can be explained well by the variation of the spin electron transport confinement due to the specular reflection effect of the nano‐oxide layer. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)