bluuebunny/crossref_metadata_2025 huggingface dataset:
Himmelreich Tunnel on the Hausmannstätten bypass – from investigation heading to completely lined tunnel / Ortsumfahrung Hausmannstätten Tunnel Himmelreich – Vom Erkundungsstollen zum Vollausbau
Authors: Reichard Norbert , Voringer Jürgen , Rappold Michael
Published: October 2011

The enormous traffic congestion on the B73 road has significantly worsened the original quality of living in the residential area of Hausmannstätten in the Austrian state of Styria. The bypass currently under construction ought lead to a considerable improvement. The route of the Hausmannstätten bypass starts in the west at the connection to the existing state road B73 and runs 2,320 m to the east. In the central section, the route passes under the Himmelreich mountain ridge through the approximately 1, 045 m long Himmelreich Tunnel and then connects again to the existing B73.

Starting from the west portal, an investigation heading altogether 740 m long that also serves as a drainage heading was constructed in 2005 and 2006. Since 2010, the consortium ÖSTU‐STETTIN‐HINTEREGGER has been working on the full construction Himmelreich Tunnel under a contract awarded by the office of the Styrian state government.

Die enorme Verkehrsbelastung der B73 hat die ursprüngliche Lebensqualität im Ortsgebiet Hausmannstätten in der Steiermark wesentlich verschlechtert. Eine deutliche Verbesserung kann durch die derzeit im Bau befindliche Ortsumfahrung erzielt werden. Die Trasse der Ortsumfahrung Hausmannstätten beginnt im Westen mit dem Anschluss an die bestehende Landesstraße B73 und erstreckt sich über eine Länge von 2.320 m nach Osten. Im mittleren Abschnitt quert die Trasse den Bergrücken Himmelreich mit dem rund 1.045 m langen Tunnel Himmelreich und schließt dann wieder an die bestehende Landesstraße B73 an.

Vom Westportal aus wurde in den Jahren 2005 bis 2006 ein insgesamt ca. 740 m langer Erkundungsstollen, der gleichzeitig als Entwässerungsstollen dient, hergestellt. Seit 2010 erfolgt durch die ARGE ÖSTU‐STETTIN‐HINTEREGGER, im Auftrag vom Amt der Steiermärkischen Landesregierung, der Vollausbau des Tunnels Himmelreich.
Trace fossils and palaeoenvironments of the Middle Devonian Caherbla Group, Dingle Peninsula, southwest Ireland
Authors: Morrissey Lance B. , Braddy Simon , Dodd Chris , Higgs Kenneth T. , Williams Brian P. J.
Published: October 2011

Trace fossils from the Middle Devonian Caherbla Group of the Dingle Peninsula, southwest Ireland, record a diverse arthropod fauna inhabiting a hot‐arid intracontinental rift setting. Aeolian dunefield and coeval fluvial interdune deposits interfinger spatially and temporally with alluvial fan sedimentary rocks. Three distinct trace fossil assemblages are recognized. The Taenidium‐Scoyenia ichnocoenosis occurs in alluvial fan and fluvial channel deposits, and includes the large backfilled burrow Taenidium, interpreted as eoarthropleurid aestivation chambers. The Rusophycus‐Protichnites ichnocoenosis, composed of arthropod trackways and surface pits, occurs in an interdune ponded area that was susceptible to ephemeral fluvial flow, with Rusophycus showing preferred orientation into the oncoming palaeocurrent. Both the Taenidium‐Scoyenia and Rusophycus‐Protichnites ichnocoenoses are assignable to the globally recurring continental Scoyenia ichnofacies. They are clearly substrate‐controlled and moisture‐related due to the ephemeral nature of the fluvial system. The Palmichnium‐Entradichnus ichnocoenosis occurs in aeolian dune deposits, and includes Palmichnium, attributed to large stylonurid eurypterids, and Diplichnites, attributed to eoarthropleurids. These trackways represent the activities of dune pioneers that left their fluvial habitat to forage for detritus. Interface burrows (Entradichnus, Palaeophycus) were also constructed by arthropods moving just under the sand surface and vertical burrows (Cylindricum, Pustulichnus) were made by arthropods digging downward. Trace preservation in the aeolian environment was probably enhanced by heavy nocturnal dew‐fall or light rain. The Palmichnium‐Entradichnus ichnocoenosis is assigned to the globally recurring aeolian Octopodichnus‐Entradichnus ichnofacies. This aeolian facies, and associated ichnofauna described herein, represents the oldest development of a unique erg system in the Old Red Sandstone (Devonian) of the southern British Isles, and one of the oldest and most diverse aeolian ichnofaunas to be reported worldwide. Copyright © 2011 John Wiley & Sons, Ltd.
The effect of hypointense white matter lesions on automated gray matter segmentation in multiple sclerosis
Authors: Gelineau‐Morel Rose , Tomassini Valentina , Jenkinson Mark , Johansen‐Berg Heidi , Matthews Paul M. , Palace Jacqueline
Published: October 2011

Previous imaging studies assessing the relationship between white matter (WM) damage and matter (GM) atrophy have raised the concern that Multiple Sclerosis (MS) WM lesions may affect measures of GM volume by inducing voxel misclassification during intensity‐based tissue segmentation. Here, we quantified this misclassification error in simulated and real MS brains using a lesion‐filling method. Using this method, we also corrected GM measures in patients before comparing them with controls in order to assess the impact of this lesion‐induced misclassification error in clinical studies. We found that higher WM lesion volumes artificially reduced total GM volumes. In patients, this effect was about 72% of that predicted by simulation. Misclassified voxels were located at the GM/WM border and could be distant from lesions. Volume of individual deep gray matter (DGM) structures generally decreased with higher lesion volumes, consistent with results from total GM. While preserving differences in GM volumes between patients and controls, lesion‐filling correction revealed more lateralised DGM shape changes in patients, which were not evident with the original images. Our results confirm that WM lesions can influence MRI measures of GM volume and shape in MS patients through their effect on intensity‐based GM segmentation. The greater effect of lesions at increasing levels of damage supports the use of lesion‐filling to correct for this problem and improve the interpretability of the results. Volumetric or morphometric imaging studies, where lesion amount and characteristics may vary between groups of patients or change over time, may especially benefit from this correction. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
Modeling conflict and error in the medial frontal cortex
Authors: Mayer Andrew R. , Teshiba Terri M. , Franco Alexandre R. , Ling Josef , Shane Matthew S. , Stephen Julia M. , Jung Rex E.
Published: October 2011

Despite intensive study, the role of the dorsal medial frontal cortex (dMFC) in error monitoring and conflict processing remains actively debated. The current experiment manipulated conflict type (stimulus conflict only or stimulus and response selection conflict) and utilized a novel modeling approach to isolate error and conflict variance during a multimodal numeric Stroop task. Specifically, hemodynamic response functions resulting from two statistical models that either included or isolated variance arising from relatively few error trials were directly contrasted. Twenty‐four participants completed the task while undergoing event‐related functional magnetic resonance imaging on a 1.5‐Tesla scanner. Response times monotonically increased based on the presence of pure stimulus or stimulus and response selection conflict. Functional results indicated that dMFC activity was present during trials requiring response selection and inhibition of competing motor responses, but absent during trials involving pure stimulus conflict. A comparison of the different statistical models suggested that relatively few error trials contributed to a disproportionate amount of variance (i.e., activity) throughout the dMFC, but particularly within the rostral anterior cingulate gyrus (rACC). Finally, functional connectivity analyses indicated that an empirically derived seed in the dorsal ACC/pre‐SMA exhibited strong connectivity (i.e., positive correlation) with prefrontal and inferior parietal cortex but was anti‐correlated with the default‐mode network. An empirically derived seed from the rACC exhibited the opposite pattern, suggesting that sub‐regions of the dMFC exhibit different connectivity patterns with other large scale networks implicated in internal mentations such as daydreaming (default‐mode) versus the execution of top‐down attentional control (fronto‐parietal). Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
Optimized neural coding? control mechanisms in large cortical networks implemented by connectivity changes
Authors: Cross Katy A. , Iacoboni Marco
Published: October 2011

Using functional magnetic resonance imaging, we show that a distributed fronto‐parietal visuomotor integration network is recruited to overcome automatic responses to both biological and nonbiological cues. Activity levels in these areas are similar for both cue types. The functional connectivity of this network, however, reveals differential coupling with thalamus and precuneus (biological cues) and extrastriate cortex (nonbiological cues). This suggests that a set of cortical areas equally activated in two tasks may accomplish task goals differently depending on their network interactions. This supports models of brain organization that emphasize efficient coding through changing patterns of integration between regions of specialized function. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc.
Discharge dependence of stream albedo in a steep proglacial channel
Authors: Richards J. , Moore R. D.
Published: October 2011

Stream surface albedo was measured at a location downstream of Place Glacier, Canada, in a steep bouldery channel. Portions of the water surface were visibly aerated as a result of the cascading flow even at lower discharges; at high flows, the stream was near‐continuous whitewater. Albedo generally increased with discharge, from around 0.1 at the lower flows to 0.4 at the highest flows. This increase is consistent with the known effect of aeration on the reflectance of water. This discharge dependence of albedo needs to be accounted for in physically based models for predicting stream temperature to avoid biased predictions of net radiation. For steep proglacial streams that experience decreasing late‐summer flows as a result of ongoing and future glacier recession, the associated decrease in albedo could promote higher stream temperatures, in addition to the effects of reduced flow depth and velocity. Copyright © 2011 John Wiley & Sons, Ltd.
Membrane composition of jetted lipid vesicles: a Raman spectroscopy study
Authors: Kirchner Silke R. , Ohlinger Alexander , Pfeiffer Tom , Urban Alexander S. , Stefani Fernando D. , Deak Andras , Lutich Andrey A. , Feldmann Jochen
Published: October 2011

Microfluidic jetting is a promising method to produce giant unilamellar phospholipid vesicles for mimicking living cells in biomedical studies. We have investigated the chemical composition of membranes of vesicles prepared using this approach by means of Raman scattering spectroscopy. The membranes of all jetted vesicles are found to contain residuals of the organic solvent decane used in the preparation of the initial planar membrane. The decane inclusions are randomly distributed over the vesicle surface area and vary in thickness from a few to several tens of nanometers. Our findings point out that the membrane properties of jetted vesicles may differ considerably from those of vesicles prepared by other methods and from those of living cells. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Increased N‐acetylaspartate in model mouse of pelizaeus‐merzbacher disease
Authors: Takanashi Jun‐ichi , Saito Shigeyoshi , Aoki Ichio , Barkovich A. James , Ito Yukiko , Inoue Ken
Published: October 2011

Purpose:

To evaluate the N‐acetylaspartate (NAA) and N‐acetylaspartylglutamate (NAAG) biochemical pathways in the brain of myelin synthesis‐deficient (msd) mouse, a model of Pelizaeus‐Merzbacher disease (PMD).

Materials and Methods:

We performed magnetic resonance imaging and proton magnetic resonance spectroscopy (1H‐MRS) of the thalamus for msd and wildtype mice with a 7.0 T magnet. NAA and NAAG were independently measured by high‐performance liquid chromatography (HPLC). Immunohistochemical analysis using anti‐Mbp, Gfap, Ng2, and NeuN antibodies were also performed.

Results:

1H‐MRS in msd mice revealed increased total NAA (tNAA, NAA+NAAG), creatine, glutamine, and glutamate and decreased choline (Cho). HPLC analysis revealed increases of both NAA and NAAG in the msd brains. Histologically, the msd brains revealed hypomyelination and astrogliosis. Oligodendrocyte progenitor cells and neurons were normal in number in the thalamus wherein 1H‐MRS was obtained.

Conclusion:

The evidence suggests that the neurochemical derangement in the msd mice may be a primary increase of NAA resulting in a secondary increase of NAAG. Increased tNAA with decreased Cho detectable on 1H‐MRS may be an important marker for PMD, and might be used to distinguish it from more common neurological disorders that have decreased tNAA. J. Magn. Reson. Imaging 2012;418‐425. © 2011 Wiley Periodicals, Inc.
Atomic decomposition for weighted Besov and Triebel‐Lizorkin spaces
Authors: Izuki Mitsuo , Sawano Yoshihiro
Published: October 2011

Rychkov defined weighted Besov spaces and weighted Triebel‐Lizorkin spaces coming with a weight in the class \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$A_p^{\rm loc}$\end{document}, which is even wider than the class Ap due to Muckenhoupt. In the present paper we are concerned with the atomic decomposition of these spaces. As an application, we obtain some key theorems in the theory of function spaces. Finally we conclude this paper with some helpful examples showing the difference between weighted spaces and unweighted spaces.
The influence of annealing on the crystallization and tribological behavior of MWNT/PEEK nanocomposites
Authors: Coban Onur , Ozgur Bora Mustafa , Avcu Egemen , Sinmazcelik Tamer
Published: October 2011

In this study, annealing influence on crystallization and scratch behavior of neat and multi‐wall carbon nanotube (MWNT) reinforced poly(ether ether ketone) (PEEK) nanocomposites have been investigated. Crystallization behavior of normal and annealed samples was investigated by using differential scanning calorimeter (DSC). Scratch behavior of normal and annealed samples was investigated by using micro scratch tester. In DSC analysis, it was detected that, melting enthalpy of annealed neat PEEK was increased sharply when compared to neat PEEK. Melting enthalpies of annealed PEEK nanocomposites prepared with addition of up to 1 wt% MWNT were increased with a decreased trend. However, nanocomposites with higher contents of MWNTs (>1 wt%) were dramatically affected by annealing process and melting enthalpy decreased sharply. Friction coefficient values of “annealed MWNT reinforced PEEK composites” were found to be lower than “normal PEEK composites.” Annealing process affects scratch hardness of both annealed and MWNT reinforced PEEK. Annealed nanocomposites with various MWNT concentrations showed higher scratch hardness values than normal PEEK nanocomposites. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers
On the longitudinal compressive strength prediction of unidirectional laminated composites based on an improved model
Authors: Yongbo Zhang , Huimin Fu
Published: October 2011

The compressive failure of unidirectional (UD) composite laminates is investigated using an improved model. Most of the existing models to predict the compressive strength of UD composites are either based on microbuckling or kinking of fibers. However, the failure mechanism analysis based on the SEM microscopy observations of failed specimens shows that the two mechanisms are responsible for the failure simultaneously when kinking occurs following the microbuckling of fibers. Therefore, the fiber microbuckling and fiber kinking models are combined to predict the compressive strength of UD T300/QY8911 composite laminate. Furthermore, this study proposes a new model for the stiffness of the foundation determination, making the predicted microbuckling strength closer to its real value. Also the effects of parameters presented in the prediction formula on the compressive strength are discussed, and it is found that the Young's modulus of matrix is the most important parameter. The predicted compressive strength using the improved model with combined modes shows a very good agreement with the experiment measurement. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers
A bead‐based approach for large‐scale identification of in vitro kinase substrates
Authors: Zhang Manyu , Han Guanghui , Wang Chunli , Cheng Kai , Li Ruibin , Liu Hongwei , Wei Xiaoluan , Ye Mingliang , Zou Hanfa
Published: October 2011

Deciphering the kinase–substrate relationship is vital for the study of phosphorylation network. The use of immobilized proteins on protein chip as the library for screening of potential kinase substrates is a tried‐and‐tested method. However, information on phosphorylation sites is lacking and the creation of the library with proteins of whole proteome by recombinant expression is costly and difficult. In this study, a new solid‐phase approach by immobilization of proteins from cell lysate onto beads as a protein library for kinase substrate screening was developed. It was found that consensus phosphorylation sites motif for kinase substrates could be accurately determined and hundreds of in vitro kinase substrates and their phosphorylation sites could be identified by using this method.
Degrading Mountain Permafrost in Southern Norway: Spatial and Temporal Variability of Mean Ground Temperatures, 1999–2009
Authors: Isaksen Ketil , Ødegård Rune Strand , Etzelmüller Bernd , Hilbich Christin , Hauck Christian , Farbrot Herman , Eiken Trond , Hygen Hans Olav , Hipp Tobias Florian
Published: October 2011

A ten‐year record (1999–2009) of annual mean ground surface temperatures (MGSTs) and mean ground temperatures (MGTs) was analysed for 16 monitoring sites in Jotunheimen and on Dovrefjell, southern Norway. Warming has occurred at sites with cold permafrost, marginal permafrost and deep seasonal frost. Ongoing permafrost degradation is suggested both by direct temperature monitoring and indirect geophysical surveys. An increase in MGT at 6.6–9.0‐m depth was observed for most sites, ranging from ~0.015 to ~ 0.095°C a‐1. The greatest rate of temperature increase was for sites having MGTs slightly above 0°C. The lowest rate of increase was for marginal permafrost sites that are affected by latent heat exchange close to 0°C. Increased snow depths and an increase in winter air temperatures appear to be the most important factors controlling warming observed over the ten‐year period. Geophysical surveys performed in 1999 to delineate the altitudinal limit of mountain permafrost were repeated in 2009 and 2010 and indicated the degradation of some permafrost over the intervening decade. Copyright © 2011 John Wiley & Sons, Ltd.
Carbidopa enhances antitumoral activity of bicalutamide on the androgen receptor‐axis in castration‐resistant prostate tumors
Authors: Thomas Christian , Wafa Latif A. , Lamoureux Francois , Cheng Helen , Fazli Ladan , Gleave Martin E. , Rennie Paul S.
Published: October 2011

BACKGROUND

Response to bicalutamide after castration failure is not durable and treatment options at this stage are limited. Carbidopa, an L‐dopa decarboxylase (AR‐coactivator) inhibitor, has been shown to retard prostate tumor growth/PSA production in xenografts. Here, we hypothesize that pharmacological targeting of the AR‐axis by combination treatment with bicalutamide plus carbidopa significantly enhances antitumoral activity in vitro and in vivo compared to monotherapy with either drug.

METHODS

Carbidopa was tested for its ability to enhance the effects of bicalutamide on cell viability, apoptosis and PSA transactivation in LNCaP and C4‐2 cells. The castration‐resistant prostate cancer (CRPC) LNCaP xenograft tumor model was used in vivo. After CRPC progression, mice were treated with carbidopa (50 mg/kg) and bicalutamide (50 mg/kg) as monotherapy or in combination. Tumor volume and serum PSA were evaluated weekly.

RESULTS

Combination treatment of carbidopa plus bicalutamide significantly inhibited cell viability in both cell lines and induced apoptosis. The combination treatment also decreased androgen‐induced PSA transactivation by 62.6% in LNCaP cells and by 55.6% in C4‐2 cells compared to control, while bicalutamide monotherapy reduced PSA levels by 27.5% and 29.1% in LNCaP and C4‐2 cells. In vivo, bicalutamide monotherapy delayed LNCaP CRPC tumor growth rate by 72.2%, while combination treatment reduced tumor growth by 84.4% compared to control. Serum PSA was also reduced 70.6% with bicalutamide monotherapy, while combination therapy reduced PSA levels by 76.7% compared to control.

CONCLUSIONS

This study demonstrates preclinical proof‐of‐principle that pharmacological targeting of prostate tumors by combination treatment of bicalutamide plus carbidopa significantly reduces AR activity, and thereby delays CRPC tumor progression in vivo. Prostate 72:875–885, 2012. © 2011 Wiley Periodicals, Inc.
Targeting of hepatocellular carcinoma with glypican‐3‐targeting peptide ligand
Authors: Lee You La , Ahn Byeong‐Cheol , Lee Yongjin , Lee Sang‐Woo , Cho Je‐Yoel , Lee Jaetae
Published: October 2011

Hepatocellular carcinoma is a common malignancy. The carcinoma cells express glypican‐3 (GPC‐3) on the cell membrane. GPC‐3 is also expressed in melanoma cells. Therefore, GPC‐3 might be a potential target for tumor imaging or therapy. Here, proteomic mass spectrometry was used to identify peptides that target GPC‐3‐expressing tumors. A mammalian expression vector expressing a FLAG‐GPC‐3 fusion protein was cloned for immunoprecipitation. With the use of liposomes, the vector was transfected into HepG2 (HepG2/FLAG‐GPC‐3) and HEK 293 cells, and the transfected cell lines were selected with geneticin. HepG2/FLAG‐GPC‐3 cells were used for immunoprecipitation of FLAG‐GPC‐3 fusion protein. Seven peptide candidates (L1–L7) were selected for GPC‐3‐targeting ligands by mass spectrometric analysis. The L5 peptide with 14 amino acids (Arg‐Leu‐Asn‐Val‐Gly‐Gly‐Thr‐Tyr‐Phe‐Leu‐Thr‐Thr‐Arg‐Gln) showed selective binding to the GPC‐3‐expressing tumor cells, as did a shortened L5 peptide (L5‐2) with seven amino acids (Tyr‐Phe‐Leu‐Thr‐Thr‐Arg‐Gln). These peptide ligands have potential as targeting moieties to GPC‐3‐expressing tumors for diagnostic and/or therapeutic purposes. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.
Determination of the density of ultrathin La films in La/B4C layered structures using X‐ray standing waves
Authors: Makhotkin I. A. , Louis E. , van de Kruijs R. W. E. , Yakshin A. E. , Zoethout E. , Seregin A. Yu. , Tereschenko E. Yu. , Yakunin S. N. , Bijkerk F.
Published: October 2011

Using simultaneous analysis of both the grazing incidence X‐ray reflectivity (GIXR) and the angular dependent fluorescence yield from ultrathin layer structures, the densities of thin La and LaN layers of 2–6 nm thickness enclosed by B4C layers have been determined with approximately 5% precision. The density of the La layer in these systems is found to be reduced to the bulk La value. This is explained by LaB6 interlayers formation. The density of LaN layers were similar to the bulk LaN value, which favors this compound as the most energetically stable in LaN/B4C layered systems.
Study of oxide precipitates in silicon using X‐ray diffraction techniques
Authors: Caha Ondřej , Bernatová Silvie , Meduňa Mojmír , Svoboda Milan , Buršík Jiří
Published: October 2011

The results of a study of oxide precipitates in Czochralski (CZ) grown silicon using two X‐ray diffraction methods are reported. The diffuse scattering around the Bragg diffraction maxima was measured on a series of samples after various two‐stage annealing treatment. Combining the analysis of diffuse scattering with other experimental techniques we were able to determine mean precipitate size and deformation field around the precipitates. The obtained data show that the deformation field is proportional to the precipitate volume and independent on the annealing temperature or annealing time. The dynamical diffraction in Laue geometry was used to measure precipitate concentration. The results are compared to the selective etching concentration measurement.
Temperature dependence of exciton–phonon‐induced sidebands in arbitrary carbon nanotubes
Authors: Bobkin Evgeny , Malic Ermin
Published: October 2011

We present a microscopic approach based on the many‐body density matrix formalism for the study of exciton–phonon‐induced features in absorption spectra of carbon nanotubes with an arbitrary chiral angle and diameter. The introduction of excitonic wave functions already containing the influence of the Coulomb interaction allows us to focus on the contribution of phonons. We observe the formation of pronounced sidebands on both sides of the zero‐phonon line. We study the behaviour of exemplary nanotubes belonging to the two semiconducting and one metallic family with respect to the spectral weight transfer from the zero‐phonon line to the exciton–phonon sidebands at different temperatures.
Adaptation of a commercial Raman spectrometer for multiline and broadband laser operation
Authors: Fábián Gábor , Kramberger Christian , Friedrich Alexander , Simon Ferenc , Pichler Thomas
Published: October 2011

A commercial single laser line Raman spectrometer is modified to accommodate multiline and tunable dye lasers, thus combining the high sensitivity of such single monochromator systems with broadband operation. Such instruments rely on high‐throughput interference filters that perform both beam alignment and Rayleigh filtering. Our set‐up handles this dual task with two independent elements: a beam splitter and a long pass filter. Filter rotation shifts the transmission passband, effectively expanding the range of operation. Operation is demonstrated on single‐walled carbon nanotubes, for which the set‐up was optimized. As the set‐up operates with standard optical elements it can be customized for specific needs with relative ease.
Electronic properties of hydrogenated quasi‐free‐standing graphene
Authors: Haberer D. , Petaccia L. , Wang Y. , Quian H. , Farjam M. , Jafari S. A. , Sachdev H. , Federov A. V. , Usachov D. , Vyalikh D. V. , Liu X. , Vilkov O. , Adamchuk V. K. , Irle S. , Knupfer M. , Büchner B. , Grüneis A.
Published: October 2011

Tailoring the electronic properties of graphene is of fundamental interest regarding its application in electronic devices. One of the key strategies is chemical functionalization which modifies the π‐electron system and thus can induce band gaps. However, in order to control the degree of functionalization it is crucial to know the exact amount of the chemisorbed species. We show with angle‐resolved photoemission spectroscopy (ARPES) the formation of a band gap in graphene and estimate the hydrogen coverage from the scattering rate. Using X‐ray photoemission spectroscopy (XPS) we identify the chemical environments in hydrogenated graphene and determine the total hydrogen to carbon (H/C)‐ratio directly from the spectra. We then compare ARPES and XPS as tools for determining the H/C‐ratio and discuss the results from molecular dynamics (MD) simulations.

magnified image

Angle‐resolved photoemission spectra of (left panel) pristine graphene intercalated with Au and (right panel) hydrogenated graphene on Au with an estimated H‐coverage of 5.8%. Besides the formation of a band gap, a broadening is observable which can be used to determine the H amount. Both spectra show the π‐band at the K‐point.
Role of nitrogen distribution in asymmetric Stone–Wales defects on electronic transport of graphene nanoribbons
Authors: Zeng Hui , Zhao Jun , Wei Jianwei , Xu Dahai
Published: October 2011

The authors performed first principles calculation to investigate the influences of nitrogen dopant distribution in the asymmetric Stone–Wales (SW) defect on the electronic transport of zigzag‐edged graphene nanoribbon (ZGNR). The stability of doped configurations are evaluated in terms of total energies. It is found that the dopant placed near the edge of the ribbon is the most energetically favorable site. Our results reveal that the doped nanostructures can be substantially modulated as a result of modifications on electronic bands induced by substitutional dopant. Moreover, the individual dopant gives rise to one or two complete electron backscattering centers associated with impurity states in the doped configurations, and the location is determined by the dopant site.

magnified image

Schematics of the atomic structure after asymmetric Stone–Wales defects introduced and different nitrogen substitutional sites.
Defense role of the cocoon in the silk worm Bombyx mori L.
Authors: Pandiarajan Jeyaraj , Cathrin Britto P. , Pratheep Thangaraj , Krishnan Muthukalingan
Published: October 2011

Silk from the domesticated silk worm Bombyx mori procures foreign body response naturally, so it has been utilized as a biomaterial for decades. In India the prime focus of the sericulture industry is to improve silk production with high quality silk. Naturally, the silk worm builds its cocoon not only with silk proteins, but also with antimicrobial proteins to avoid infection since the cocoon is non‐motile and non‐feeding. The aim of the present study is to elucidate the antimicrobial proteins that persist in the cocoon of the silk worm Bombyx mori. At the pupal stage, the silk worm cocoon shell extract was prepared from the day of pupation (P0) to the day of natural rupture of the cocoon for the eclosion of moth (NR). Using the cocoon shell extract a microbial susceptibility test was performed by the disc diffusion method against the microbes Escherchia coli, Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae. The development of a zone of inhibition against the microbes confirmed the presence of antimicrobial/immunogenic activity of the cocoon shell extract. For further analysis, the cocoon shell extract was subjected to 7–15% sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS‐PAGE). The protein profile of the cocoon extract revealed the coomassie blue stained bands resolved from the 150 – 15 kDa molecular range. Interestingly, a polypeptide localized at around 29 kDa showed remarkable expressional changes during the development of pupa. To characterize the 29 kDa protein, it was eluted from the gel, digested with trypsin and analyzed by matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS). The trypsin‐digested peptide peaks were analyzed through MASCOT and peptides were matched with the NCBI nr database. The peptides were very well matched with the 18 wheeler protein, which is reported to be responsible for innate immunity, belonging to the Toll family in insects and responsible for cellular mediated immunity. Copyright © 2011 John Wiley & Sons, Ltd.
Isotopic turnover of a submersed macrophyte following transplant: the roles of growth and metabolism in eutrophic conditions
Authors: Xu Jun , Cao Te , Zhang Min , Li Zhongqiang , Zhang Meng , Ni Leyi , Xie Ping
Published: October 2011

Stable isotopic turnover with isotopic change due to growth and metabolic tissue replacement associated with a change in environmental conditions is a critical aspect of the use of stable isotope analyses as time‐integrating tracers of resource‐consumer interactions. However, stable isotopic turnover in plants remains poorly understood compared with those of animals, and here we used continuous flow elemental analyzer‐isotopic ratio mass spectrometry (EA‐IRMS) to analyse the turnover of stable carbon and nitrogen isotopes in a submersed macrophyte (Vallisneria natans) after transplantation to hypereutrophic and mesoeutrophic treatments in a field mesocosm experiment. The direction and magnitude of the isotopic shifts of V. natans were suggested to be determined by the inorganic nutrient availability and its isotopic content in the different treatments. Based on the modelling results of turnover, the contribution of growth to the isotopic turnover was as high as those observed in various aquatic ectotherms. However, the contribution of metabolism was also considerable, especially for nitrogen in the hypereutrophic treatment, which was argued to be a response, co‐occurring with growth inhabitation and biochemical disorder of V. natans, to the stress induced by the eutrophication. Our results indicated that isotope turnover in a macrophyte is a feasible technique for estimating its ecophysiological conditions in the natural environment, and that it may facilitate understanding of isotopic data in field studies of food web and habitat restoration under eutrophic conditions. Copyright © 2011 John Wiley & Sons, Ltd.
Dual buffer gases for ion manipulation in a miniature ion trap mass spectrometer with a discontinuous atmospheric pressure interface
Authors: Chen Tsung‐Chi , Xu Wei , Ouyang Zheng
Published: October 2011

The discontinuous atmospheric pressure interface (DAPI) has been developed to allow a direct transfer of ions from atmosphere into an ion trap mass spectrometer with minimum pumping capability. Air is introduced into the trap with ions and used as a buffer gas for the ion trap operation. In this study, a method of introducing helium as a second buffer gas was developed for a miniature mass spectrometer using a dual DAPI configuration. The buffer gas effects on the performance of a linear ion trap (LIT) with hyperbolic electrodes were characterized for ion isolation, fragmentation and a mass‐selective instability scan. Significant improvement was obtained with helium for resolutions of mass analysis and ion isolation, while moderate advantage was gained with air for collision‐induced dissociation. The buffer gas can be switched between air and helium for different steps within a single scan, which allows further optimization of the instrument performance for tandem mass spectrometry. Copyright © 2011 John Wiley & Sons, Ltd.
End‐group characterization of poly(styrene sulfonate sodium salt) by activated electron photo‐detachment dissociation
Authors: Girod Marion , Antoine Rodolphe , Lemoine Jérôme , Dugourd Philippe , Charles Laurence
Published: October 2011

Tandem mass spectrometry of poly(styrene sulfonate sodium salt) (PSS) was performed after activated electron photo‐detachment dissociation (activated EPD). In this technique, doubly charged PSS oligomers were first produced in negative mode electrospray ionization, then oxidized into radical anions upon electron photo‐detachment using a 220 nm laser wavelength, and further activated by collision. In contrast to the collision‐induced dissociation (CID) of negatively charged PSS oligomers, which does not provide informative data with regard to the end‐groups, activated‐EPD is shown here to promote radical‐induced dissociation reactions thanks to the oxidation of a sulfonate group upon laser irradiation. Major product ions generated after backbone bond cleavages contained one or the other chain terminations and could be accounted for by two main mechanisms. Moreover, each of the proposed dissociation reactions was shown to generate two distinct fragments, depending on the location of the oxidized monomer near one or the other chain terminal moieties. As a result, a combination of these two fragments allowed a straightforward mass characterization of each end‐group. Copyright © 2011 John Wiley & Sons, Ltd.
How to obtain and use X‐Ray projection microscopy in the SEM
Authors: Horn H. R. F. , Waltinger H. G.
Published: October 2011

The primary electron beam of an SEM is used to generate a point source of x‐rays, permitting x‐ray microscopy within the SEM.

The practical device described fits into the sample chamber of an SEM. Exact and reproducible adjustabilities of the sample support and the film holder allow two x‐ray micrographs, e.g. stereo‐micrographs, to be taken in one run without repressurization of the specimen chamber. By comparing x‐ray and SEM micrographs of the same sample in the identical position it is possible to get additional information concerning surface morphology and inner structure of a specimen.
The tandem scanning reflected light microscope
Authors: Petráň M. , Hadravský M. , Boyde A.
Published: October 2011

Reflected light microscopy of biological material has been a very difficult task and many different but hardly successful attempts have been made to get usable images. The main reasons for this state are: Weak reflections from the biologically important structures in the object as against strong reflection at its surface; reflections at optical surfaces in the microscope which cause a deterioration of contrast; and the mixing together of reflections from many levels in the object so that the signal coming from the focussed‐on level is lost in noise and d.c. components.

We tried, and successfully, to reverse this situation and to make it possible for the signal to overwhelm spurious and scattered light using double, or, as we call it, tandem scanning. The object is illuminated only in small patches lying in one plane and moving across this plane, and only the light reflected from these illuminated patches is allowed to pass into the image plane and participate in image formation. The image consists of points which travel over the image plane and which are geometrical images of the illuminated patches in the focussed‐on object plane. To ensure that only the light belonging to these geometrical images be allowed to enter the image, the image plane is covered with an opaque diaphragm having holes in locations exactly corresponding to the locations of the geometrical images of the illuminated object points; this diaphragm travels in concordance with the first scanning and so the complete image of the focussed‐on object plane is formed successively.

Both scans are performed by a single device, a Nipkow disc carrying in its annular periphery several ten thousands of holes arranged in Archimedean spirals. The disc is 100 mm in diameter and rotates about 100 rpm driven by an electric motor. On one side the disc is illuminated in a circle 18 mm in diameter, and the light transmitted through several hundred holes and reflected in a mirror system passes a microscope objective which forms the images of the disc holes in the object plane. The light reflected here passes through the same objective and mirror system (one mirror being a “limitlessly thin” beam splitter) to pass conjugate aperture holes on the observation side of the Nipkow disc. As the disc lies at the intermediate image plane of the objective lens on both its illuminating and observation sides, only light emanating from reflection or fluorescence in the plane of focus can contribute to the image. High contrast images of very thin focussed‐on layers are thus formed.

The practical arrangements are such that very large specimens can be examined: The specimens for this microscope need not themselves be microscopic.
XPS determination of uranium oxidation states
Authors: Ilton Eugene S. , Bagus Paul S.
Published: October 2011

This contribution is both a review of different aspects of X‐ray photoelectron spectroscopy that can help one determine U oxidation states and a personal perspective on how to effectively model the X‐ray photoelectron spectroscopy of complicated mixed‐valence U phases. After a discussion of the valence band, the focus lingers on the U4f region, where the use of binding energies, satellite structures, and peak shapes is discussed in some detail. Binding energies were shown to be very dependent on composition/structure and consequently unreliable guides to oxidation state, particularly where assignment of composition is difficult. Likewise, the spin orbit split 4f7/2 and 4f5/2 peak shapes do not carry significant information on oxidation states. In contrast, both satellite‐primary peak binding energy separations, as well as intensities to a lesser extent, are relatively insensitive to composition/structure within the oxide–hydroxide–hydrate system and can be used to both identify and help quantify U oxidation states in mixed valence phases. An example of the usefulness of the satellite structure in constraining the interpretation of a complex multivalence U compound is given. Copyright © 2011 John Wiley & Sons, Ltd.
Atomistische Simulation von amorphen TiO2‐Strukturen für optische Schichtsysteme
Authors: Köhler Thomas , Dolgonos Grygoriy , Frauenheim Thomas
Published: October 2011

Zielsetzung des vorliegenden Beitrages ist es, einen kurzen Überblick über die Möglichkeiten der Modellierung oxidischer optischer Materialien, am Beispiel des amorphen Titanoxids (TiO2), zu geben. Im Vordergrund steht hierbei ein effizientes approximatives Dichtefunktional‐basiertes Verfahren (DFTB), mit dem es möglich ist, Einsicht in lokale Struktur‐Eigenschaftsbeziehungen auf atomarer Basis zu bekommen. Perspektivisch werden Wege aufgezeigt, die Erkenntnisse auf andere Problemklassen, z. B. Grenzflächen zu übertragen, deren Optimierung größerskalige Betrachtungen erfordern. Die Studien sind im Rahmen des PLuTO‐Pilotprojektes zur Plasmaabscheidung optischer Schichtsysteme eingebettet.
Vakuum‐ und Plasmagestützte Dünnschichttechnik – wohin geht die Reise?
Authors: Blau Winfried
Published: October 2011

Das Programm der V2011 – Industrieausstellung & Workshop‐Woche „Vakuumbeschichtung und Plasmaoberflächentechnik”︁ liegt vor, vgl. S. 42 in diesem Heft. Das Programm ist nach Anwendungsgebieten gegliedert, eine gute Gelegenheit zu fragen, wo liegen auf diesen Gebieten die gegenwärtigen Schwerpunkte, welche davon sind möglicherweise zukunftsträchtig.
Use of the CEARXRF GUI‐Based Monte Carlo–Library Least‐Squares (MCLLS) Code for the Micro‐Focused EDXRF analyzer
Authors: Gardner Robin P. , Li Fusheng
Published: October 2011

The CEARXRF GUI‐Based Monte Carlo–Library Least‐Squares (MCLLS) Code is demonstrated with results from a micro‐focused EDXRF analyzer, which can be used to calculate elemental weight fractions in metal alloys or rock samples accurately by library least‐squares regression of the measured X‐ray spectrum with computer‐generated elemental library spectra. An elemental stratified sampling variance reduction technique has been implemented in the CEARXRF5 code, which equalizes the statistical precision of the elemental libraries within the measured sample independent of the relative elemental amounts that are present. Also, an improved Si(Li) detector response function (DRF) has been obtained for micro‐focused X‐ray fluorescence (XRF) analyzers, and the DRF parameters are obtained based on regression from pure elemental experimental spectra. It is demonstrated that the resulting MCLLS approach can greatly improve the accuracy of elemental XRF analysis results. Copyright © 2011 John Wiley & Sons, Ltd.
Long‐Term Impact of Pretransplant and Posttransplant Diabetes Mellitus on Kidney Transplant Outcomes
Authors: Tsai Jen‐Pi , Lian Jong‐Da , Wu Sheng‐Wen , Hung Tung‐Wei , Tsai Hui‐Ching , Chang Horng‐Rong
Published: October 2011

Background

The aim of this study was to compare the impact of preexisting diabetes mellitus (pre‐DM), posttransplant DM (PTDM), and non‐DM on the long‐term outcomes of renal transplant recipients (RTRs).

Methods

This is a retrospective observational cohort study of 427 RTRs who underwent transplantation from 1999 to 2008. Patients were divided into non‐DM, pre‐DM, and PTDM groups. The primary outcome was the composite of doubling of the serum creatinine (SCr) level, graft failure, or death. Secondary outcomes were biopsy‐proven acute rejection (BPAR), biopsy‐proven interstitial fibrosis and/or tubular atrophy (IF/TA), and individual components of the primary outcome.

Results

A total of 70 patients (16.4%) had pre‐DM, 104 (24.2%) had PTDM, and 253 (59.3%) had non‐DM. Kaplan–Meier analysis indicated significant differences in the development of the primary outcome: p = 0.003 (log rank test). Relative to the non‐DM group, the pre‐DM group had a 6.36‐fold increased risk [95% confidence interval (CI) 2.43–16.33; p < 0.001), and the PTDM group had a 2.00‐fold increased risk (95% CI 1.08–3.73; p = 0.029) for development of the primary outcome. Patients in the pre‐DM group had 6.73‐fold (95% CI 2.46–18.42; p < 0.001), 4.56‐fold (95% CI 1.77–11.78; p = 0.002), and 13.95‐fold (95% CI 2.96–65.75; p < 0.001) increased risks for the development of SCr doubling, biopsy‐proven IF/TA, and death‐censored graft failure, respectively. Patients in the PTDM group had a 2.09‐fold (95% CI 1.10–3.99; p = 0.025), increased risk for the development of SCr doubling.

Conclusions

The presence of pre‐DM or PTDM significantly impaired kidney allograft outcome.
No Outcome Differences between a Laparoscopic and Retroperitoneoscopic Approach in Synchronous Bilateral Adrenal Surgery
Authors: Miccoli Paolo , Materazzi Gabriele , Brauckhoff Michael , Ambrosini Carlo Enrico , Miccoli Mario , Dralle Henning
Published: October 2011

Background

Two main approaches have been described for endoscopic adrenalectomy: the transperitoneal approach with the patient in the lateral decubitus position (LA) and the retroperitoneal approach with the patient in the prone position (ERA). The goal of the present study was to compare the results of LA and ERA for endoscopic bilateral synchronous adrenalectomy.

Patients and Methods

Between 1994 and 2008, 34 patients underwent bilateral synchronous adrenalectomy in two referral centers: 20 patients underwent LA in Pisa (group A), and 14 patients underwent ERA in Halle (group B). Sex, age, preoperative diagnosis, body mass index, preoperative medical treatments, diameter of glands, blood loss, operative time, complications, conversion, intensive care unit stay, day of first oral intake, length of postoperative recovery, histology report, and outcome were analyzed.

Results

There were 7 men and 13 women in group A and 6 men and 8 women in group B. Mean age was 48.1 years in group A and 38.9 years in group B. Body mass index was similar in the two groups. Diameters of the glands were larger in group A than in group B, at 61.1 versus 42.8 mm for the right side and 64.1 versus 37.4 mm for the left side. Mean hospital stay was longer in group B (8.2 versus 5.25 days; P = 0.002), whereas the intensive care unit stay was longer in group A (1.44 versus 1 day).

Conclusions

It is not possible to determine which of the two approaches is better; both are feasible, safe, and effective and patient outcomes are almost the same.