bluuebunny/crossref_metadata_2025_split huggingface dataset:
High‐fat diet reduces levels of type I tropocollagen and hyaluronan in rat skin
Authors: Yamane Takumi , Kobayashi‐Hattori Kazuo , Oishi Yuichi , Takita Toshichika 
Published: April 2010

AbstractAlthough it is known that nutritional conditions affect the skin function, little information is available on the effect of a high‐fat (HF) diet on skin. In this study, Sprague–Dawley rats were fed HF diets for 28 days, and we investigated the effect of this diet on type I tropocollagen and hyaluronan in rat skin. The HF diets reduced the levels of type I tropocollagen, COL1A1 mRNA, hyaluronan, and rat hyaluronan synthase (rhas)2 mRNA, which play a primary role in hyaluronan synthase in the dermis. However, rhas3 mRNA level in the skin was increased. The HF diets also decreased the skin mRNA expression of transforming growth factor (TGF)‐β1, which enhances the expression of COL1A1 and rhas2 mRNA and decreases rhas3 mRNA expression, and decreased the hepatic mRNA expression of insulin‐like growth factor (IGF)‐I, which enhances COL1A1, rhas2, and TGF‐β1 mRNA expression. The serum level of adiponectin, which promotes the syntheses of type I collagen and hyaluronan, was decreased in the HF diet groups. These findings suggest that an HF diet reduces the levels of type I tropocollagen and hyaluronan in the skin by suppressing the action of TGF‐β1, IGF‐I and adiponectin, and these effects are deleterious for skin function.
Fractionated manganese injections: effects on MRI contrast enhancement and physiological measures in C57BL/6 mice
Authors: Grünecker Barbara , Kaltwasser Sebastian F. , Peterse Yorick , Sämann Philipp G. , Schmidt Mathias V. , Wotjak Carsten T. , Czisch Michael 
Published: April 2010

AbstractManganese‐enhanced MRI (MEMRI) is an increasingly used imaging method in animal research, which enables improved T1‐weighted tissue contrast. Furthermore accumulation of manganese in activated neurons allows visualization of neuronal activity. However, at higher concentrations manganese (Mn2+) exhibits toxic side effects that interfere with the animals' behaviour and well‐being. Therefore, when optimizing MEMRI protocols, a compromise has to be found between minimizing side effects and intensifying image contrast. Recently, a low concentrated fractionated Mn2+ application scheme has been proposed as a promising alternative. In this study, we investigated effects of different fractionated Mn2+ dosing schemes on vegetative, behavioural and endocrine markers, and MEMRI signal contrast in C57BL/6N mice. Measurements of the animals' well‐being included telemetric monitoring of body temperature and locomotion, control of weight and observation of behavioural parameters during the time course of the injection protocols. Corticosterone levels after Mn2+ application served as endocrine marker of the stress response. We compared three MnCl2 · 4H2O application protocols: 3 times 60 mg/kg with an inter‐injection interval of 48 h, six times 30 mg/kg with an inter‐injection interval of 48 h, and 8 times 30 mg/kg with an inter‐injection interval of 24 h (referred to as 3 × 60/48, 6 × 30/48 and 8 × 30/24, respectively). Both the 6 × 30/48 and the 8 × 30/24 protocols showed attenuated effects on animals' well‐being as compared to the 3 × 60/48 scheme. Best MEMRI signal contrast was observed for the 8 × 30/24 protocol. Together, these results argue for a fractionated application scheme such as 30 mg/kg every 24 h for 8 days to provide sufficient MEMRI signal contrast while minimizing toxic side effects and distress. Copyright © 2010 John Wiley & Sons, Ltd.
Combined DCE‐MRI and single‐voxel 2D MRS for differentiation between benign and malignant breast lesions
Authors: Lipnick Scott , Liu Xiaoyu , Sayre James , Bassett Lawrence W. , DeBruhl Nanette , Thomas M. Albert 
Published: April 2010

AbstractDynamic contrast‐enhanced (DCE) magnetic resonance imaging (MRI) and proton (1H) magnetic resonance spectroscopy (MRS) provide structural and biochemical information, including vascular volume, vascular permeability and tissue metabolism. In this study, we performed analysis of the enhancement characteristic from DCE‐MRI and the biochemical information provided by two‐dimensional (2D) Localized Correlated Spectroscopy (L‐COSY) MRS to determine the sensitivity and specificity of using DCE‐MRI alone compared to the combination with 2D MRS. The metabolite ratios from the 2D MRS spectra were analyzed using multivariate statistical analyses to determine a method capable of automatic separation of the patient cohort into malignant and benign lesions. A total of 24 lesions were studied with 21 diagnosed accurately using the enhancement characteristics alone resulting in sensitivity and specificity of 100% and 73%, respectively. Analysis of the 2D MRS data demonstrated a significant difference (p < 0.05) in 12 of 18 metabolite ratios analyzed for malignant compared to benign lesions. Previous research focused on utilizing the choline signal to noise ratio (SNR) as a marker for malignancy has been verified using 2D MRS in this study. Using Fisher's linear discriminant test using water (WAT)/olefinic fat diagonal (UFD), choline (CHO)/fat (FAT), CHO/UFD, and FAT/methyl fat (FMETD) as predictors the sensitivity and specificity increased to 92% and 100%, respectively. Using the Classification and Regression Tree (CART) statistical analysis the resulting sensitivity and specificity were 100% and 91%, respectively, with the most accurate predictor for differentiating malignant and benign determined to be FAT/FMETD. The cases within the study that presented a indeterminate diagnosis using DCE‐MRI alone were able to be accurately diagnosed when the metabolic information from 2D MRS was incorporated. The results suggest improved breast cancer detection through the combination of morphological and enhancement information from DCE‐MRI and metabolic information from 2D MRS. Copyright © 2010 John Wiley & Sons, Ltd.
Life cycle analysis of organic photovoltaic technologies
Authors: García‐Valverde Rafael , Cherni Judith A. , Urbina Antonio 
Published: April 2010

AbstractOrganic solar cells, both in the hybrid dye sensitized technology and in the full organic polymeric technology, are a promising alternative that could supply solar electricity at a cost much lower than other more conventional inorganic photovoltaic technologies. This paper presents a life cycle analysis of the laboratory production of a typical bulk heterojunction organic solar cell and compares this result with those obtained for the industrial production of other photovoltaic technologies. Also a detailed material inventory from raw materials to final photovoltaic module is presented, allowing us to identify potential bottlenecks in a future supply chain for a large industrial output. Even at this initial stage of laboratory production, the energy payback time and CO2 emission factor for the organic photovoltaic technology is of the same order of other inorganic photovoltaic technologies, demonstrating that there is plenty of room for improvement if the fabrication procedure is optimized and scaled up to an industrial process. Copyright © 2010 John Wiley & Sons, Ltd.
Mechanisms of wafer sawing and impact on wafer properties
Authors: Bidiville A. , Wasmer K. , Michler J. , Nasch P. M. , Van der Meer M. , Ballif C. 
Published: April 2010

AbstractSilicon wafer wire‐sawing experiments were realized with different sets of sawing parameters, and the thickness, roughness, and cracks depth of the wafers were measured. The results are discussed in relation to assumptions underlying the rolling–indenting model, which describes the process. It was also found that the silicon surface at the bottom of the sawing groove is different from the wafer surface, implying different sawing conditions in the two positions. Furthermore, the measured parameters were found to vary along the wire direction, between the entrance of the wire in the ingot and its exit. Based on these observations, some improvements for the wire‐sawing model are discussed. Copyright © 2010 John Wiley & Sons, Ltd.
Anodic oxides on a beta type Nb–Ti alloy and their characterization by electrochemical impedance spectroscopy
Authors: Woldemedhin Michael Teka , Raabe Dierk , Hassel Achim Walter 
Published: April 2010

AbstractAnodic oxides were grown on the surface of an electropolished (Ti–30 at% Nb) beta‐titanium (β‐Ti) alloy by cyclic voltammetry. The scan rate was 100 mV s−1 between 0 and 8 V in increments of l V in an acetate buffer of pH 6.0. Electrochemical impedance spectroscopy was carried out right after each anodic oxide growth increment to study the electronic properties of the oxide/electrolyte interface in a wide frequency range from 100 kHz to 10 MHz with an AC perturbation voltage of 10 mV. A film formation factor of 2.4 nm V−1 was found and a relative permittivity number (dielectric constant) of 42.4 was determined for the oxide film formed. Mott–Schottky analysis on a potentiostatically formed 7 nm thick oxide film was performed to assess the semiconducting properties of the mixed anodic oxide grown on the alloy. A flat band potential of −0.47 V (standard hydrogen electrode, SHE) was determined, connected to a donor density of 8.2 × 1017 cm−3. β‐Ti being highly isotropic in terms of mechanical properties should be superior to the stiffer α‐Ti compound. Its application, however, requires a passivation behaviour comparable or better than α‐Ti which in fact is found.
Reduced activation ODS ferritic steel – recent development in high speed hot extrusion processing
Authors: Oksiuta Zbigniew , Lewandowska Małgorzata , Kurzydlowski Krzysztof , Baluc Nadine 
Published: April 2010

AbstractThe paper presents the microstructure and mechanical properties of an oxide dispersion strengthened (ODS), reduced activation, ferritic steel, namely the Fe‐14Cr‐2W‐0.3Ti‐0.3Y2O3 alloy, which was fabricated by hot isostatic pressing followed by high speed hydrostatic extrusion (HSHE) and heat treatment HT at 1050 °C. Transmission electron microscopy (TEM) observations revealed significant differences in the grain size and dislocation density between the as‐HIPped and as‐HSHE materials. It was also found that the microstructure of the steel is stable after HT. The HSHE process improves significantly the tensile and Charpy impact properties of the as‐HIPped steel. The ultimate tensile strength at room temperature increases from 950 up to 1350 MPa, while the upper shelf energy increases from 3.0 up to 6.0 J. However, the ductile‐to‐brittle transition temperature (DBTT) remains relatively high (about 75 °C).These results indicate that HSHE is a promising method for achieving grain refinement and thus improving the mechanical properties of ODS ferritic steels.
Carbon nanotube‐supported bimetallic palladium–gold electrocatalysts for electro‐oxidation of formic acid
Authors: Chen Cheng‐Han , Liou Wei‐Jen , Lin Hong‐Ming , Wu She‐Huang , Mikolajczuk Anna , Stobinski Leszek , Borodzinski Andrzej , Kedzierzawski Piotr , Kurzydlowski Krzysztof 
Published: April 2010

AbstractIt is known that palladium‐based catalysts are initially very active in direct formic acid oxidation but they suffer from fast deactivation caused by a strongly adsorbed CO intermediate. Reactivation of the catalysts involving application of anodic potential may cause palladium dissolution. The aim of the present study is to increase the stability and performance of palladium‐based catalysts in direct formic acid fuel cells (DFAFCs). Preparation and characterization of palladium/multiwalled carbon nanotubes (Pd/MWCNTs) and towards formic acid oxidation via different treatments are described. The catalysts were characterized by thermogravimetric analysis (TGA), X‐ray diffraction (XRD), transmission electron microscopy (TEM) and cyclic voltammetry (CV). It was shown that the Pd and Pd–Au MWCNTs supported catalysts after reduction in H2–Ar at 200 °C (R200 treatment) were highly active in formic acid electro‐oxidation, whereas the catalysts after heating in argon at 250 °C (C250 treatment) were inactive. The catalysts after hydrogen treatment have smaller metal particles and better contact with MWCNTs support. CV, simulating reactivation of the catalysts, showed that the Pd catalyst suffers from severe Pd dissolution, whereas for the Pd–Au selective leaching of Pd is considerably slower.
Observation and enhancement of visible photoluminescence of PECVD a‐SiOx:H (x < 2) thin films by microcavity effect
Authors: Bacıoğlu Akın , Kodolbaş Alp Osman , Öktü Özcan 
Published: April 2010

Abstracta‐SiOx:H (x < 2) thin film samples prepared in a PECVD system by using SiH4+CO2 gas mixture show strong room temperature visible photoluminescence (PL) at a photon energy of 2.1 eV. The PL spectrum of a single layer sample was observed to reshape due to the multiple reflection between two interfaces of the film. The orders of the resonance modes in the PL spectrum range of 1.5 eV‐2.5 eV, were calculated to be within a range of m=8 to m=13. The peak energy of the most intense mode (m=11) was observed at 2.1 eV and the half width and the quality factor of the microcavity were calculated as Δν=20 THz and Q=20, respectively. Two multi‐layered distributed Bragg reflectors (10 and 25 layer pairs) were fabricated with two different refractive indices (n1=3.2 and n2=2.4) of the layers with λ/4 (λ0=580nm) optical thickness. The PL intensity was detected increasing in intensity around the photon energy of 2 eV and the other modes were suppressed. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mechanical response of nanocrystalline Cu from atomistic simulations
Authors: Galanis Nikos V. , Remediakis Ioannis N. , Kopidakis Georgios 
Published: April 2010

AbstractWe perform atomistic simulations for the structure and elastic properties of nanocrystalline Cu. We observe softening at small grain sizes, in analogy with the reverse Hall‐Petch effect for plastic deformations in nanocrystalline metals. The decrease of elastic constants is explained by the increase of the fraction of grain boundary atoms for smaller grains. By decomposing the energy into contributions from atoms in the bulk of grains and at interfaces, we derive simple scaling relations for various properties as a function of the average grain size. These theoretical predictions fit very well the simulation data, as well as published data for nanocrystalline diamond. This suggests that softening at small grain sizes is a general nanoscale effect. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nanocrystallization of Al‐based glasses via nucleation and growth under “soft impingement” conditions
Authors: Rassolov Sergey , Tkatch Victor , Maslov Valeriy , Maksimov Victor , Svyrydova Kateryna , Zhikharev Igor 
Published: April 2010

AbstractThe nanocrystallization behaviour of Al86Ni6Co2Gd3Y2Tb1 amorphous alloy has been studied by X‐ray diffraction methods involving small angle scattering, resistance measurements and differential scanning calorimetry. It has been established that the transformation in amorphous alloy investigated occurs mainly by the growth process at initial state of transformation while at final stage nucleation contributes into formation of nanocomposite structure. In order to describe the nanocrystallization kinetics of the Al‐based glasses the analytical kinetic equations in the frames of Kolmogorov‐Johnson‐Mehl‐Avrami model have been proposed and the effective volume diffusion coefficient values which govern the diffusion‐limited growth nanocrystals have been determined. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Micro‐scale (1.5 µm) sulphur isotope analysis of contemporary and early Archean pyrite
Authors: Nishizawa Manabu , Maruyama Shigenori , Urabe Tetsuro , Takahata Naoto , Sano Yuji 
Published: April 2010

AbstractWe present a method for in situ sulphur (S) isotopic analysis of significantly small areas (1.5 µm in diameter) in pyrite using secondary ion mass spectrometry (NanoSIMS) to interpret microbial sulphur metabolism in the early earth. We evaluated the precision and accuracy of S isotopic ratios obtained by this method using hydrothermal pyrite samples with homogeneous S isotopic ratios. The internal precision of the δ34S value was 1.5‰ at the level of 1 sigma of standard error (named 1SE) for a single spot, while the external reproducibility was estimated to be 1.6‰ at the level of 1 sigma of standard deviation (named 1SD, n = 25). For each separate sample, the average δ34S value was comparable with that measured by a conventional method, and the accuracy was better than 2.3‰. Consequently, the in situ method is sufficiently accurate and precise to detect the S isotopic variations of small sample of the pyrite (less than 20 µm) that occurs ubiquitously in ancient sedimentary rocks. This method was applied to measure the S isotopic distribution of pyrite within black chert fragments in early Archean sandstone. The pyrite had isotopic zoning with a 34S‐depleted core and 34S‐enriched rim, suggesting isotopic evolution of the source H2S from −15 to −5‰. Production of H2S by microbial sulphate reduction (MSR) in a closed system provides a possible explanation for both the 34S‐depleted initial H2S and the progressive increase in the δ34SH2S value. Although more extensive data are necessary to strengthen the explanation for the origin of the MSR, the results show that the S isotopic distribution within pyrite crystals may be a key tracer for MSR activity in the early earth. Copyright © 2010 John Wiley & Sons, Ltd.
Enhanced surface sensitivity in secondary ion mass spectrometric analysis of organic thin films using size‐selected Ar gas‐cluster ion projectiles
Authors: Tanaka Motohiro , Moritani Kousuke , Hirota Tomokazu , Toyoda Noriaki , Yamada Isao , Inui Norio , Mochiji Kozo 
Published: April 2010

AbstractA size‐selected argon (Ar) gas‐cluster ion beam (GCIB) was applied to the secondary ion mass spectrometry (SIMS) of a 1,4‐didodecylbenzene (DDB) thin film. The samples were also analyzed by SIMS using an atomic Ar+ ion projectile and X‐ray photoelectron spectroscopy (XPS). Compared with those in the atomic‐Ar+ SIMS spectrum, the fragment species, including siloxane contaminants present on the sample surface, were enhanced several hundred times in the Ar gas‐cluster SIMS spectrum. XPS spectra during beam irradiation indicate that the Ar GCIB sputters contaminants on the surface more effectively than the atomic Ar+ ion beam. These results indicate that a large gas‐cluster projectile can sputter a much shallower volume of organic material than small projectiles, resulting in an extremely surface‐sensitive analysis of organic thin films. Copyright © 2010 John Wiley & Sons, Ltd.
Evaluation of two liquid chromatography/tandem mass spectrometry platforms for quantification of monensin in animal feed and milk
Authors: Dai Susie Y. , Herrman Timothy J. 
Published: April 2010

AbstractMonensin is an anticoccidial drug that has been used as an additive in medicated feed. The United States Food and Drug Administration (USFDA) has included monensin in the national surveillance schemes for residues in foodstuff. In this study, two simple, selective and rapid methods were developed to determine monensin content in animal feed and milk. The methods enabled the detection of monensin residues as low as 1 ppb. Moreover, the two methods were used as models to compare two common liquid chromatography/tandem mass spectrometry (LC/MS/MS) platforms; an LC linear ion trap (LC/LIT) and an LC triple quadrupole (LC/QqQ). The two instrument platforms were evaluated for their matrix effect dependence, precision and accuracy. The LC/QqQ presented a lower limit of detection and limit of quantitation (LOD and LOQ) and showed less matrix dependence as compared to the LC/LIT. The LC/QqQ instrument also demonstrated a better intermediate precision. For example, the intermediate precision standard deviation calculated for 27 analyses across three days was 4% and 11% for LC/QqQ and LC/LIT, respectively. Overall, the LC/QqQ represents a better choice for analysis of monensin with respect to LOD, LOQ, matrix interference and precision. Copyright © 2010 John Wiley & Sons, Ltd.
A fast gas chromatography/mass spectrometry method for the determination of stimulants and narcotics in urine
Authors: Rossi Sabina Strano , de la Torre Xavier , Botrè Francesco 
Published: April 2010

AbstractA fast method has been developed for the simultaneous determination of 52 stimulants and narcotics excreted unconjugated in urine by gas chromatography/mass spectrometry (GC/MS). The procedure involves the liquid/liquid extraction of the analytes from urine at strong alkaline pH and the injection of the extract into a GC/MS instrument with a fast GC column (10 m × 0.18 mm i.d.); the short column allows the complete separation of the 52 analytes in a chromatographic run of 8 min. The method has been fully validated giving lower limits of detection (LLODs) satisfactory for its application to antidoping analysis as well as to forensic toxicology. The repeatability of the concentrations and the retention times are good both for intra‐ and for inter‐day experiments (%CV of concentrations always lower than 15 and %CV of retention times lower than 0.6). In addition, the analytical bias is satisfactory (A% always >15%). The method proposed here would be particularly useful whenever there are time constraints and the analyses have to be completed in the shortest possible time. Copyright © 2010 John Wiley & Sons, Ltd.
A tool for the spectroscopic investigation of hydrogen–silicon interaction
Authors: Romano E. , Cerofolini G. F. , Narducci D. , Corni F. , Frabboni S. , Ottaviani G. , Tonini R. 
Published: April 2010

AbstractThe preparation of an array of nanocavities (NCs) in silicon via thermal treatments of high‐fluence helium‐implanted silicon is a well‐established process. The NCs have offered a powerful tool for the preparation of well‐defined and ordered internal silicon surface, enabling the experimental investigation of its free energy. Here, instead, we interpret the NCs as an ideal nanolaboratory for the study of the adsorption and desorption of H2 on silicon. We will present the determination of the internal pressure through the equilibrium abundances of monohydride dimers and dihydrides obtained with infrared spectroscopy. Copyright © 2010 John Wiley & Sons, Ltd.
Depth of brain fissures in normal fetuses by prenatal ultrasound between 19 and 30 weeks of gestation
Authors: Alonso I. , Borenstein M. , Grant G. , Narbona I. , Azumendi G. 
Published: April 2010

AbstractObjectiveTo establish normal reference ranges for the depth of the insula and Sylvian (SF), parieto‐occipital (POF) and calcarine (CF) fissures on prenatal ultrasound between 19 and 30 weeks of gestation.MethodsThis was a prospective study of 15 consecutive normal fetuses per gestational week between 19 + 0 and 30 + 6 weeks. We measured the depth of the insula and SF in a standard transventricular axial plane of the fetal head; the depth of the POF in a plane above and parallel to that used for the insula; and the depth of the CF in a coronal view of the posterior fossa. All measurements were done transabdominally during the routine second‐ or third‐trimester examination. Reproducibility for each of the parameters was assessed by two operators using stored images from 30 cases.ResultsThe depth of the four structures increased with increasing gestational age. The insula and SF could be seen in all cases from 19 weeks onwards, while the POF and CF could be identified in 93.3% and 6.6% of cases, respectively, at 19 weeks. From 20 weeks onwards, the POF could be seen in all examinations, as could the CF from 24 weeks. Intra‐ and interobserver reproducibility analysis showed good results.ConclusionsAssessment of the insula, SF, POF and CF is feasible during prenatal ultrasound examination using standard views of the fetal head. Since the normal ranges increase with gestational age, they could be used to estimate brain development. It is possible that this assessment might be incorporated into the neurosonogram to identify fetuses at risk of maturation disorders or as a complement to other standard evaluations. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.