bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth of Diamond Nanoplatelets by CVD
Authors: Chen Hou‐Guang , Chang Li , Cho Shih‐Yin , Yan Jhih‐Kun , Lu Chun‐An
Published: August 2008

Hexagonal, single‐crystalline, diamond nanoplatelets synthesized by microwave plasma (MP)CVD on Au‐Ge alloy and nanocrystalline diamond (nc‐diamond) film substrates, respectively, are reported. On the nc‐diamond matrix, hexagonal diamond nanoplatelets can grow to a thickness of as little as approximately 10 nm. The effects of various processing parameters, such as methane concentration, microwave power, and gas pressure, on the growth of diamond nanoplatelets are explored. High‐resolution transmission electron microscopy (HRTEM) reveals that the diamond nanoplatelets contain multi‐parallel twins, and the side faces of the platelets exhibit {100}/{111} ridge‐and‐trough structure. Anisotropic growth of diamond nanoplatelet is believed to result from the side face structure of the twinned platelets and intensive plasma reaction.
Nanodiamond‐Coated Carbon Nanotubes: Early Stage of the CVD Growth Process
Authors: Orlanducci Silvia , Tamburri Emanuela , Terranova Maria Letizia , Rossi Marco
Published: August 2008

A series of deposits formed by single‐walled carbon nanotube (SWNT) bundles coated by nanocrystalline diamond (NCD) are produced using a modified CVD reactor. The nanocylindrical structures are deposited on Si substrates using carbon nanopowders and atomic H as reactants. The nanocrystalline coating obtained from short‐time runs lasting up to 6 min are analyzed by micro‐Raman and cathodoluminescence (CL) techniques, in order to obtain information on the structural evolution of the material during the first steps of the growth process. The morphological investigation performed by field emission scanning electron microscopy (FESEM) indicates that the nanocrystalline coating generated by a process lasting 4–6 min is formed by protruding embryo diamond crystallites with a needle‐like shape. Thereafter the shape of the diamond phase evolves giving rise to elongated and better faceted diamond grains well anchored on the nanotube bundle surfaces.
Molecular Dynamics Simulations of the Sticking and Etch Behavior of Various Growth Species of (Ultra)Nanocrystalline Diamond Films
Authors: Eckert Maxie , Neyts Erik , Bogaerts Annemie
Published: August 2008

The reaction behavior of species that may affect the growth of ultrananocrystalline and nanocrystalline diamond ((U)NCD) films is investigated by means of molecular dynamics simulations. Impacts of CHx (x= 0– 4), C2Hx (x = 0 – 6), C3Hx (x = 0 – 2), C4Hx (x = 0 – 2), H, and H2 on clean and hydrogenated diamond (100)2 × 1 and (111)1 × 1 surfaces at two different substrate temperatures are simulated. We find that the different bonding structures of the two surfaces cause different temperature effects on the sticking efficiency. These results predict a temperature‐dependent ratio of diamond (100) and (111) growth. Furthermore, predictions of which are the most important hydrocarbon species for (U)NCD growth are made.
Surface Science Contribution to the BEN Control on Si(100) and 3C‐SiC(100): Towards Ultrathin Nanocrystalline Diamond Films
Authors: Arnault Jean‐Charles , Saada Samuel , Delclos Sophie , Rocha Licinio , Intiso Luciana , Polini Riccardo , Hoffman Alon , Michaelson Shaul , Bergonzo Philippe
Published: August 2008

Deposition of thin and smooth nanocrystalline diamond films requires a high degree of control of the nucleation stage. The nature of the interface between diamond film and substrate is also important for some applications. The successive steps of the bias‐enhanced nucleation (BEN) process are studied in‐situ on Si(100) and 3C‐SiC(100) using electron spectroscopies. Thin nanodiamond films (80–900 nm) have been achieved on Si(100). The formation of a thin covering SiC layer (2–3 nm) during the plasma exposure for parameters stabilization (PEPS) step leads us to study the plasma/surface interactions on 3C‐SiC(100) surfaces. The C‐terminated 3C‐SiC(100) demonstrates a large inertia under microwave plasma (MP)CVD conditions. An enhancement of diamond nucleation on this surface is observed. Moreover, surface analysis reveals very little damage after BEN on 3C‐SiC surfaces.
A Theoretical Study of Nitrogen‐Induced Effects on Initial Steps of Diamond CVD Growth
Authors: Van Regemorter Tanguy , Larsson Karin
Published: August 2008

An investigation based on an ultra‐soft, pseudo‐potential, density functional theory (DFT) method, using a generalized gradient approximation (GGA) under periodic boundary conditions, is performed in order to investigate the effect of substitutional nitrogen on the CH3 adsorption and the H abstraction from the adsorbed CH3 species. Both (111) and (100)‐2x1 surface are considered with 4 and 6 substitutional N positions, respectively. For the two surface orientations, no strong effect of N is generally observed when positioning it within the first C layer (i.e., surface layer). The only exception is for N in one of three investigated first layer positions within the (100) surface, for which a spontaneous β‐scission occurs as a result of the H abstraction reaction. For N in the second carbon layer, the CH3 adsorption reaction is calculated to be strongly disfavored, whilst the H abstraction reaction is markedly improved.
Modelling the Influence of the Nucleation Density on Ultra Nano Crystalline Diamond Growth Morphology: Preliminary Results
Authors: Sternschulte Hadwig , Rabl Helga E. , Steinmüller‐Nethl Doris , Tilg Bernhard
Published: August 2008

The morphology of ultra nanocrystalline diamond (UNCD) films is modeled by a pure geometrical approach. Diamond spheres with a fixed radius are added randomly spread on a smooth substrate surface covered with diamond seeds in varied primary nucleation density. The secondary nucleation rate and the nucleation density on the bare substrate define the distribution of diamond spheres during each cycle. In preliminary results, this simple geometrical model leads to good comparison with published experimental data; low primary nucleation densities yield to the growth of separated diamond islands with a rough surface, the smoothest films are obtained with the highest primary nucleation densities.
First Total Synthesis of the Potent Anticancer Natural Product Dideoxypetrosynol A: Preparation of the “Skipped” (Z)‐Enediyne Moiety by Oxidative Coupling of Homopropargylphosphonium Ylide
Authors: Gung Benjamin W. , Omollo Ann O.
Published: August 2008

Dideoxypetrosynol A is a C30 polyacetylenic alcohol with C2 symmetry. The first total synthesis of both enantiomers of the potent anti‐cancer natural product (+)‐ and (–)‐dideoxypetrosynol A is reported. The key step is an oxidative coupling of a homopropargylphosphonium ylide to prepare the “skipped” (Z)‐enediyne moiety. The natural dideoxypetrosynol A was isolated as a racemic mixture as shown in structure 1. The absolute configurations of the chiral centers are established for the (+)‐ and (–)‐enantiomers using Burgess' enzymatic resolution procedure with Pseudomonas AK lipase. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Simultaneous determination of nandrolone, testosterone, and methyltestosterone by multi‐immunoaffinity column and capillary electrophoresis
Authors: Qi Xiao‐Hua , Zhang Li‐Wei , Zhang Xin‐Xiang
Published: August 2008

A multitarget antibody immunoaffinity column was proposed for the purification and enrichment of nandrolone, testosterone, and methyltestosterone from urine. Nandrolone‐3‐site substituted antigen was designed and synthesized and the polyclonal antibody was prepared with immunizing rabbits. The stationary phase of the immunoaffinity column was synthesized by covalently bonding the antibodies specific to nandrolone, testosterone, and methyltestosterone onto CNBr‐actived Sepharose 4B. The analytes of interest were extracted with a methanol/water mixture in one step. The immunoaffinity column showed high affinity and high selectivity to a class of structurally related compounds. The elution was then transferred to a micellar electrokinetic CE system with a running buffer of sodium borate and sodium cholate for separation and determination. Recoveries of the three steroids from complex matrix were 88–94% with RSD values less than 5.2%. Optimization of the immunoaffinity column purification was achieved and the feasibility of the technique for the analysis of steroid hormone was discussed. The results indicated that the combination of multi‐immunoaffinity column and CE was an effective technique, which was rapid, simple, and sensitive for the assay of steroids.
Bilayer disk capillary electrophoresis: A novel method to study drug partitioning into membranes
Authors: Boija Elisabet , Lundquist Anna , Nilsson Mikael , Edwards Katarina , Isaksson Roland , Johansson Gunnar
Published: August 2008

CE in the presence of lipid bilayer disks was introduced as a new approach in membrane partitioning studies. The disks were used as a pseudostationary phase in the partial‐filling mode of CE and the partitioning of cationic drugs was determined. The migration times of the analytes increased linearly with the lipid amount in the system. An appropriate algorithm for the calculation of a partition coefficient is presented. In the disk‐shaped bilayers, which have excellent stability and shelf life, all of the lipids are readily available for interaction and the disks can be used as realistic cell membrane models.
Use of chemometric methodology in optimizing conditions for competitive binding partial filling affinity capillary electrophoresis
Authors: Montes Ruth E. , Hanrahan Grady , Gomez Frank A.
Published: August 2008

This work expands the knowledge of the use of chemometric response surface methodology (RSM) in optimizing conditions for competitive binding partial filling ACE (PFACE). Specifically, RSM in the form of a Box–Behnken design was implemented in flow‐through PFACE (FTPFACE) to effectively predict the significance of injection time, voltage, and neutral ligand (neutral arylsulfonamide) concentration, [Lo], on protein–neutral ligand binding. Statistical analysis results were used to create a model for response surface prediction via contour and surface plots at a given maximum response (ΔRMTR) to reach a targeted Kb = 2.50×106 M−1. The adequacy of the model was then validated by experimental runs at the optimal predicted solution (injection time = 2.3 min, voltage = 11.6 kV, [Lo] = 1.4 μM). The achieved results greatly extend the usefulness of chemometrics in ACE and provide a valuable statistical tool for the study of other receptor–ligand combinations.
Poly(methyl methacrylate) microchip affinity capillary gel electrophoresis of aptamer–protein complexes for the analysis of thrombin in plasma
Authors: Obubuafo Anne , Balamurugan Subramanian , Shadpour Hamed , Spivak David , McCarley Robin L. , Soper Steven A.
Published: August 2008

Thrombin generation in blood serves as an important marker for various hemostasis‐related diseases and conditions. Analytical techniques currently utilized for determining the thrombin potential of patients rely primarily on the enzymatic activity of thrombin. Microfluidic‐based ACE using fluorescently labeled aptamers as affinity probes could provide a simple and efficient technique for the real‐time analysis of thrombin levels in plasma. In this study, aptamers were used for the analysis of thrombin by affinity microchip CGE. The CGE used a poly(methyl methacrylate) (PMMA) microfluidic device for the sorting of the affinity complexes with a linear polyacrylamide (LPA) serving as the sieving matrix. Due to the fact that the assay was run under nonequilibrium electrophoresis conditions, the presence of the sieving gel was found to stabilize the affinity complex, providing improved electrophoretic performance compared to free‐solution electrophoresis. Two fluorescently labeled aptamer affinity probes, HD1 and HD22, which bind to exosites I and II, respectively, of thrombin were investigated. With an electric field strength of 300 V/cm, two well‐resolved peaks corresponding to free aptamer and the thrombin–aptamer complex were obtained in less than 1 min of separation time with a run‐to‐run and chip‐to‐chip reproducibility (RSD) of migration times <10% using both aptamers. HD22 affinity assays of thrombin produced baseline‐resolved peaks with favorable efficiency due to its higher binding affinity, whereas HD1 assays showed poorer resolution of the free aptamer and complex peaks. HD22 was used in determining the level of thrombin in human plasma. Assays were performed directly on plasma that was diluted to 10% v/v. Thrombin was successfully analyzed by microchip CGE at a concentration level of 543.5 nM for the human plasma sample.
Evaluation of on‐line solid phase extraction‐capillary electrophoresis‐electrospray‐mass spectrometry for the analysis of neuropeptides in human plasma
Authors: Hernández Elena , Benavente Fernando , Sanz‐Nebot Victoria , Barbosa José
Published: August 2008

In this study, the suitability of SPE coupled on‐line to CE‐electrospray‐MS (SPE‐CE‐ESI‐MS) was evaluated for the analysis of neuropeptides in human plasma. First, CE‐ESI‐MS was investigated and a sample pretreatment based on precipitation with ACN was used for cleanup of plasma samples. The main quality parameters were determined and were consistent with those previously obtained for the analysis of standard mixtures, e.g., the LODs were of around 1 μg/mL. SPE‐CE‐ESI‐MS employing microcartridges containing a C18 stationary phase was explored in order to decrease the LODs. A double‐step sample cleanup pretreatment consisting of precipitation with ACN and ultrafiltration through 3000 Da MW cut‐off membranes was needed to prevent the microcartridge saturation. Repeatability, reproducibility, linearity, and LODs of the SPE‐CE‐ESI‐MS method and the durability of the microcartridges were studied. The LODs were markedly improved, ranging between 10 and 0.1 ng/mL depending on the peptide.
Multiplexed detection and applications for separations on parallel microchips
Authors: Dishinger John F. , Kennedy Robert T.
Published: August 2008

Much work has been performed since the development of the lab‐on‐a‐chip concept that has brought microfabricated systems to the forefront of bioanalytical research. The success of using these microchips for performing complicated biological assays faster and cheaper than conventional methods has facilitated their emerging popularity among researchers. A recently exploited advantage of microfabricated technology has led to the creation of single wafers with multiple channel manifolds for high‐throughput experiments. Efforts toward parallel microchip development have yielded fascinating new devices for chemical separations showing the potential for replacing conventional multiplexing techniques. This review will focus on recent work toward multiplexed separations on microdevices and complementary detection instrumentation.
Behavior of interacting species in vacancy affinity capillary electrophoresis described by mass balance equation
Authors: Sun Ying , Fang Ning , Chen David D. Y.
Published: August 2008

Vacancy ACE (VACE) is one of the ACE methods, and has been used to study binding interactions between different biomolecules. Thermodynamic binding constants can be estimated with nonlinear regression methods. With a highly efficient computer simulation program (SimDCCE), it is possible to demonstrate the detailed behaviors of each species during the interaction process under different conditions. In this work, thirteen scenarios in four different combinations of migration orders of the free protein, free drug, and complex formed are studied. The detailed interaction process between protein and ligand is discussed and illustrated based on the mass balance equation, also called mass transfer equation. By properly setting the parameters in the simulation model, the influence of different factors during the interaction process can be well understood.
Clinically relevant advances in on‐chip affinity‐based electrophoresis and electrochromatography
Authors: Hou Chenlu , Herr Amy E.
Published: August 2008

Clinical and point‐of‐care disease diagnostics promise to play an important role in personalized medicine, new approaches to global health, and health monitoring. Emerging instrument platforms based on lab‐on‐a‐chip technology can confer perfomance advantages successfully exploited in electrophoresis and electrochromatography to affinity‐based electrokinetic separations. This review surveys lab‐on‐a‐chip diagnostic developments in affinity‐based electokinetic separations for quantitation of proteins, integration of preparatory functions needed for subsequent analysis of diverse biological samples, and initial forays into multiplexed analyses. The technologies detailed here underpin new clinical and point‐of‐care diagnostic strategies. The techniques and devices promise to advance translation of until now laborabory‐based sample preparation and analytical assays to near‐patient settings.
Micro‐structured Devices for Chemical Sensing of Flavor and Fragrance
Authors: Schimmelpfennig M. , Dornbusch K. , Bannert M. , Feller K.‐H.
Published: August 2008

The aim of this study was to design, develop and test an integrated micro‐analytical system. Of special interest are micro‐fluidic and micro‐sensor applications in the field of chemical analysis, such as the optical detection of parameter changes, optical recognition of component profiles and technological micro‐reaction applications. For this purpose, a modular system was developed, which enables the realization of various application cases in an uncomplicated manner, and to execute (via serial or parallel combination of components) usually not compatible tasks. Software components were developed to control the measuring procedure as well as to execute the data interpretation up to a chemometrical discriminant analysis. Application is directed to the production and product control in life sciences mainly for food, natural products, cosmetics and pharmaceutics.
Solar photocatalytic removal of metal ions from industrial wastewater
Authors: Kabra Kavita , Chaudhary Rubina , Sawhney R.L.
Published: August 2008

This article describes the photocatalytic reduction and deposition of four metal ions Cr(VI), Ni(II), Zn(II), and Cu(II) present in the wastewater from a chrome plating industry using solar energy irradiated TiO2. A parabolic trough reactor was used to carry out the reaction. Experiments were carried out to find an optimum dose of hole scavenger used (citric acid). The adsorption and reduction of the metal ions at different pH values was also investigated.

It was observed that the solar photocatalytic process was effective in removing most of the metal ions in specific reaction conditions. Alkaline pH was found to be more suitable for removal of nickel and zinc. However, Cr(VI) reduced completely even at catalyst concentrations as low as 0.5 mg/L at pH 2. Maximum reaction was completed in the first 4 h of solar exposure. © 2008 American Institute of Chemical Engineers Environ Prog, 2008
Catalytic and photocatalytic degradation of ozone via utilization of controllable nano‐Ag modified on TiO2
Authors: Lin Yu‐chih , Lin Chia‐hsin
Published: August 2008

To resolve increasing ozone pollution, nano‐silver‐anchored titanium dioxide (nano‐Ag/TiO2), with a controllable diameter, synthesized by a photoreduction method, for ozone degradation is presented in this study.

In the presence of ultraviolet (UV) irradiation, the nano‐Ag/TiO2 catalyst exhibited high efficiency for ozone degradation, at ∼98–99% for all experiments. However, the efficiency of pure TiO2 for ozone degradation rapidly dropped and became inefficient after 160 min. This is because ozone oxidized the surface of TiO2 and formed an oxidative layer on the TiO2 surface; then the photocatalytic ability of the re‐oxidized TiO2 for ozone degradation was greatly reduced. The results also indicated that ozone was effectively degraded via the nano‐Ag/TiO2 catalyst even without UV irradiation. The catalytic performance of nano‐Ag/TiO2 for ozone degradation was enhanced by reducing the diameters and by effectively dispersing the Ag nanoparticles. In addition, the photocatalytic ozone degradation via nano‐Ag/TiO2 revealed no decay at a relative humidity of 70% during the experimental period, and maintained excellent performance compared with that of pure TiO2. © 2008 American Institute of Chemical Engineers Environ Prog, 2008
Dynamics of cortical responses to tone pairs in relation to task difficulty: A MEG study
Authors: Nahum Mor , Renvall Hanna , Ahissar Merav
Published: August 2008

We investigated the effect of task difficulty on the dynamics of auditory cortical responses. Whole‐scalp magnetoencephalographic (MEG) signals were recorded while subjects performed a same/different frequency discrimination task on equiprobable tone pairs applied in blocks of five, which were separated by a 10 s intertrial interval. Task difficulty was manipulated by the interpair frequency difference. The manipulation of task difficulty affected the amplitude of the N100m response to the first tone and the latency of the N100m response to the second tone in each pair. The N100m responses were smaller and peaked significantly later in the difficult than in the easy condition. The later processing field (PF) responses were longer in duration in the difficult condition. In both conditions, the duration of the PF response was negatively correlated with the subject's performance in the task, and was longer in the less successful subjects. The PF response may thus reflect the subjects' effort to resolve the task. The N100m and the PF responses did not differ between the tone pairs along the five‐pair trial as a function of task difficulty, suggesting that changes in response along the five‐pair trial are not easily affected by high‐level manipulations. Hum Brain Mapp 2009. © 2008 Wiley‐Liss, Inc.
Attentional load modifies early activity in human primary visual cortex
Authors: Rauss Karsten S. , Pourtois Gilles , Vuilleumier Patrik , Schwartz Sophie
Published: August 2008

Recent theories of selective attention assume that the more attention is required by a task, the earlier are irrelevant stimuli filtered during perceptual processing. Previous functional MRI studies have demonstrated that primary visual cortex (V1) activation by peripheral distractors is reduced by higher task difficulty at fixation, but it remains unknown whether such changes affect initial processing in V1 or subsequent feedback. Here we manipulated attentional load at fixation while recording peripheral visual responses with high‐density EEG in 28 healthy volunteers, which allowed us to track the exact time course of attention‐related effects on V1. Our results show a modulation of the earliest component of the visual evoked potential (C1) as a function of attentional load. Additional topographic and source localization analyses corroborated this finding, with significant load‐related differences observed throughout the first 100 ms post‐stimulus. However, this effect was observed only when stimuli were presented in the upper visual field (VF), but not for symmetrical positions in the lower VF. Our findings demonstrate early filtering of irrelevant information under increased attentional demands, thus supporting models that assume a flexible mechanism of attentional selection, but reveal important functional asymmetries across the VF. Hum Brain Mapp 2009. © 2008 Wiley‐Liss, Inc.
Audiovisual integration during speech comprehension: An fMRI study comparing ROI‐based and whole brain analyses
Authors: Szycik Gregor R. , Jansma Henk , Münte Thomas F.
Published: August 2008

Visual information (lip movements) significantly contributes to speech comprehension raising the question for the neural implementation of audiovisual (AV) integration during speech processing. To replicate and extend earlier neuroimaging findings, we compared two different analysis approaches in a slow event‐related fMRI study of healthy native speakers of German who were exposed to AV speech stimuli (disyllabic nouns) with audio and visual signals being either congruent or incongruent. First, data was subjected to whole brain general linear model analysis after transformation of all individual data sets into standard space. Second, a region of interest (ROI) approach based on individual anatomy was used with ROI defined in areas identified previously as being important for AV processing. Standard space analysis revealed a widespread cortical network including the posterior part of the left superior temporal sulcus, Broca's region and its right hemispheric counterpart showing increased activity for incongruent stimuli. The ROI approach allowed to identify differences in activity between Brodmann areas 44 and 45, within Broca's area for incongruent stimulation, and also allowed to study activity of subdivisions of superior temporal regions. The complementary strengths and weaknesses of the two analysis approaches are discussed. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.
Stability of tactile‐ and pain‐related fMRI brain activations: An examination of threshold‐dependent and threshold‐independent methods
Authors: Taylor Keri S. , Davis Karen D.
Published: August 2008

Functional MRI can be used to assess brain plasticity over time. To confidently attribute changes in activation patterns to cortical plasticity, it is important to establish the stability of cortical activation patterns. Because little is known concerning the stability of somatosensory‐evoked brain responses, we assessed the reproducibility of within‐subject responses in key somatosensory regions [thalamus, primary and secondary cortex (S1, S2)] to tactile and painful stimuli using threshold‐dependent and threshold‐independent analyses. Six subjects underwent four biweekly scanning sessions during which tactile and painful stimuli were applied to the hand. Standard thresholding and voxel counting techniques were compared with a novel threshold‐independent method utilizing percent signal change within the regions of interest. Contralateral S1 and S2 were qualitatively reproducible during tactile stimulation, with overlapping activations >85% of the time. S2 was also highly reproducible during painful stimulation (88%), whereas S1 was less reproducible (44%). However, activation in the thalamus to both tactile and painful stimulation was highly variable. Ipsilateral activation was consistent within S2 but sparse within S1 and thalamus. Deactivations within ipsilateral S1 occurred 48% of the time with tactile stimuli, and 90% of the time with painful stimuli. Within contralaterally activated regions intraclass correlations (ICCs) were very high using the unthresholded method regardless of the type of stimulation, whereas much lower ICCs arose from the thresholded analyses. These data indicate that a threshold‐independent analysis can produce more reproducible outcomes than a standard threshold‐dependent analysis. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.
Working memory representation in atypical language dominance
Authors: Axmacher Nikolai , Bialleck Katharina A. , Weber Bernd , Helmstaedter Christoph , Elger Christian E. , Fell Juergen
Published: August 2008

One of the most important factors controlling material specific processing in the human brain is language dominance, i.e. hemispheric specialization in semantic processes. Although previous studies have shown that lateralized long‐term memory processes in the medial temporal lobes are modified in subjects with atypical (right) language dominance, the effect of language dominance on the neural basis of working memory (WM) has remained unknown. Here, we used functional MRI (fMRI) to study the impact of language dominance on the neural representation of WM. We conducted an n‐back task in three different load conditions and with both verbal and nonverbal (spatial) material in matched groups of left and right language dominant subjects. This approach allowed us to investigate regions showing significant interactions between language dominance and material. Overall, right dominant subjects showed an increased inter‐individual variability of WM‐related activations. Verbal WM involved more pronounced activation of the left fusiform cortex in left dominant subjects and of the right inferior parietal lobule in the right dominant group. Spatial WM, on the other hand, induced activation of right hemispheric regions in left dominant subjects, but no specific activations in right dominant subjects. Taken together, these findings indicate that the neural basis of verbal WM processes depends on language dominance and is more mutable in right dominant subjects. The increased variability in right dominant subjects strongly suggests that a standard network of material‐dependent WM processes exists in left dominant subjects, and that right dominant subjects use variable alternative networks. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.
Pharyngeal swallowing dysfunction following treatment for oral and pharyngeal cancer—Association with diminished intraoral sensation and discrimination ability
Authors: Jäghagen Eva Levring , Bodin Ingrid , Isberg Annika
Published: August 2008

Background.

Swallowing disorders following treatment for oral and pharyngeal cancer are mainly considered a surgical sequel. The recent finding that radiotherapy‐induced decline in intraoral sensory abilities established an incentive to elucidate any association between the degree of sensory decline and the degree of swallowing dysfunction.

Methods.

Oral and pharyngeal swallowing was cineradiographically examined in 15 patients with oral or pharyngeal cancer before and after treatment. The patients were also tested for intraoral sensation, shape recognition, and hole size identification.

Results.

Swallowing function deteriorated in 67% of the patients 6 months posttreatment, with no significant improvement after 12 months. The degree of swallowing dysfunction was statistically significantly associated with the degree of diminished intraoral sensation and shape recognition.

Conclusion.

In the quest for rehabilitation after treatment for oral and pharyngeal cancer, the impact of impaired intraoral sensation and discrimination ability on swallowing function should be taken into consideration. © 2008 Wiley Periodicals, Inc. Head Neck, 2008
Human resource issues in outsourcing: Integrating research and practice
Authors: Fisher Sandra L. , Wasserman Michael E. , Wolf Paige P. , Wears Katherine Hannan
Published: August 2008

As the use of outsourcing as a staffing strategy continues, it is important to understand how the landscape of human resource management shifts in response to this strategy. Much of the existing outsourcing research in human resource management and organizational behavior has examined individuallevel responses. In this article, we use this research to identify the outsourcing‐related challenges facing HR professionals in both the service provider and client organizations as they strive to attract, motivate, and retain high‐performing employees and explore HR practices that may help achieve organizational goals. Areas in need of additional research are also identified. © 2008 Wiley Periodicals, Inc.
A case for sexual orientation diversity management in small and large organizations
Authors: Day Nancy E. , Greene Patricia G.
Published: August 2008

In the 14 years since the Society for Human Resource Management added sexual orientation to its nondiscrimination statement, many organizations, including a large majority of Fortune 500 companies, have become more accepting of gay and lesbian workers. However, both small and large organizations may not have decided if this diversity is a type they wish to address. This article makes the case that to be competitive in the labor market and maximize the customer base, inclusiveness may be a requirement. We make this point by first describing current practices that create inclusive environments. To explore differences between small and large employers, we then present an exploratory study that shows that small firms may already have advantages in establishing inclusiveness. Interviews are presented that further investigate how work climates may exist for gay and lesbian employees in small and large organizations. Best practices and recommendations for creating and maintaining an inclusive workforce are then presented. © 2008 Wiley Periodicals, Inc.
Subglacial modulation of the hydrograph from glacierized basins
Authors: Flowers Gwenn E.
Published: August 2008

The extent of basin glacierization has important implications for the hydrograph in part, because snow, firn and ice impart different delays in water transport through the system. Here, the significance of subglacial drainage morphology in modulating the hydrograph is examined with a one‐dimensional physically based model. The conceptual model of subglacial drainage comprises both ‘fast’ and ‘slow’ elements, respectively associated with summer and winter drainage regimes. The additional possibility of a permeable glacier substrate is taken into account by allowing water transport in a subglacial aquifer. Forced by prescribed rates of melt‐water delivery to the glacier bed, the model predicts glacier discharge by drainage system provenance. The effects of (1) ‘hard’ versus ‘soft’ glacier beds, (2) subsurface permeability and groundwater flow, and (3) glacier geometry are then investigated. Hydrograph character, in the form of peak timing and amplitude, symmetry with respect to the forcing, and the amplitude of diurnal fluctuations, is affected by the partitioning of water through the various flow elements. Hard beds and impermeable substrates maximize the discharge routed through the fast‐drainage system in the simulations, generally resulting in higher seasonal discharge maxima and stronger diurnal variations in discharge. High hydraulic transmissivities, either at the glacier bed or in underlying strata, hinder the development of the fast‐drainage system in the simulations, producing hydrographs of lower amplitude. Glacier geometry has a modest effect, with adverse bed slopes, very thick or very thin ice and short glacier lengths favouring prolonged drainage through the slow system. These results suggest that the morphology and evolution of the subglacial drainage system may play a significant role in determining the character of the hydrograph from glacierized basins. Copyright © 2008 John Wiley & Sons, Ltd.
Estimation of suspended sediment concentration and yield using linear models, random forests and quantile regression forests
Authors: Francke T. , López‐Tarazón J.A. , Schröder B.
Published: August 2008

For sediment yield estimation, intermittent measurements of suspended sediment concentration (SSC) have to be interpolated to derive a continuous sedigraph. Traditionally, sediment rating curves (SRCs) based on univariate linear regression of discharge and SSC (or the logarithms thereof) are used but alternative approaches (e.g. fuzzy logic, artificial neural networks, etc.) exist. This paper presents a comparison of the applicability of traditional SRCs, generalized linear models (GLMs) and non‐parametric regression using Random Forests (RF) and Quantile Regression Forests (QRF) applied to a dataset of SSC obtained for four subcatchments (0·08, 41, 145 and 445 km2) in the Central Spanish Pyrenees. The observed SSCs are highly variable and range over six orders of magnitude. For these data, traditional SRCs performed inadequately due to the over‐simplification of relating SSC solely to discharge. Instead, the multitude of acting processes required more flexibility to model these nonlinear relationships. Thus, alternative advanced machine learning techniques that have been successfully applied in other disciplines were tested. GLMs provide the option of including other relevant process variables (e.g. rainfall intensities and temporal information) but require the selection of the most appropriate predictors. For the given datasets, the investigated variable selection methods produced inconsistent results. All proposed GLMs showed an inferior performance, whereas RF and QRF proved to be very robust and performed favourably for reproducing sediment dynamics. QRF additionally provides estimates on the accuracy of the predictions and thus allows the assessment of uncertainties in the estimated sediment yield that is not commonly found in other methods. The capabilities of RF and QRF concerning the interpretation of predictor effects are also outlined. Copyright © 2008 John Wiley & Sons, Ltd.
Effect of obesity and other lifestyle factors on mortality in women with breast cancer
Authors: Dal Maso Luigino , Zucchetto Antonella , Talamini Renato , Serraino Diego , Stocco Carmen F. , Vercelli Marina , Falcini Fabio , Franceschi Silvia ,   for Prospective Analysis of Case‐control studies on Environmental factors and health (PACE) study group
Published: August 2008

A few lifestyle characteristics before cancer diagnosis have been suggested to modify the prognosis of breast cancer. Follow‐up information from 1,453 women with incident invasive breast cancer, diagnosed between 1991 and 1994 and interviewed within the framework of an Italian multicenter case‐control study, was used to assess the effect of obesity and of a large spectrum of other factors on breast cancer mortality. Five hundred and three deaths, including 398 breast cancer deaths, were identified. Hazard ratios (HR) for all‐cause and breast cancer mortality and corresponding 95% confidence intervals (CI), were calculated using Cox proportional hazards models and adjusted for age and breast cancer characteristics (stage and receptor status). Increased risk of death for breast cancer emerged for body mass index (BMI) ≥ 30 kg/m2(HR = 1.38; 95% CI: 1.02–1.86), compared to <25, or waist‐to‐hip ratio (WHR) ≥ 0.85 (HR = 1.27; 95% CI: 0.98–1.64), compared to <0.80, and the strongest association was observed for women with BMI ≥30 and high WHR (≥0.85), compared to women with BMI <25 and WHR < 0.85 (HR = 1.57, 95% CI: 1.08–2.27). The unfavorable effect of high BMI was similar in women <55 and ≥55 years of age, whereas it was stronger in women with I–II stage than III–IV stage breast cancer. Low vegetable and fruit consumption and current or past smoking were also associated to marginally worse breast cancer survival. No significant relationship with survival after breast cancer emerged for several other major lifestyle factors, including physical activity, alcohol drinking, exogenous hormones use and fat intake. High BMI was the lifestyle risk factor that most consistently modified breast cancer prognosis in our study. © 2008 Wiley‐Liss, Inc.
Coffee consumption and risk of endometrial cancer: A prospective study in Japan
Authors: Shimazu Taichi , Inoue Manami , Sasazuki Shizuka , Iwasaki Motoki , Kurahashi Norie , Yamaji Taiki , Tsugane Shoichiro ,   for the JPHC Study Group
Published: August 2008

Coffee has been proposed to decrease the circulating insulin and estrogen levels, which are related to the development of endometrial cancer. However, few studies have prospectively assessed the association between coffee consumption and endometrial cancer. We conducted a population‐based prospective cohort study in 53,724 Japanese women aged 40–69 years with no history of cancer at baseline in 1990–1994. We used Cox proportional hazards regression analysis to estimate the hazard ratio (HR) and 95% confidence interval (CI) of endometrial cancer incidence in relation to coffee consumption. All reported p values are 2‐tailed. During the 15‐year follow‐up period, we documented 117 cases of endometrial cancer. Coffee consumption was significantly associated with a decreased risk of endometrial cancer. After adjustment for age, study area, body mass index, menopausal status, age at menopause for postmenopausal women, parity, use of exogenous female hormones, smoking status and by consumption of green vegetables, beef, pork and green tea, the multivariate HRs (95% CI) of endometrial cancer in women who drank coffee ≤2 days/week, 3–4 days/week, 1–2 cups/day and ≥3 cups/day were 1.00, 0.97 (0.56–1.68), 0.61 (0.39–0.97) and 0.38 (0.16–0.91), respectively (p for trend = 0.007). In contrast, green tea consumption was not significantly associated with a reduced risk of endometrial cancer (p for trend = 0.22). The inverse association between coffee consumption and risk of endometrial cancer was consistently observed in subgroup analyses stratified by potential confounders. Coffee consumption may be associated with a decreased risk of endometrial cancer. © 2008 Wiley‐Liss, Inc.
Prevalence, incidence and clearance of human papillomavirus infection among young primiparous pregnant women in Kampala, Uganda
Authors: Banura Cecily , Franceschi Silvia , van Doorn Leen‐Jan , Arslan Annie , Kleter Bernhard , Wabwire‐Mangen Fred , Mbidde Edward K. , Quint Wim , Weiderpass Elisabete
Published: August 2008

The proportion of women who have already been exposed to human papillomavirus (HPV) infection by the time they first become pregnant, and the influence of pregnancy and delivery on the course of HPV infection are unclear. In Kampala, Uganda, 987 young primiparous pregnant women aged <25 years had gynaecological examination and liquid‐based cytology. In the follow‐up, women acted as their own controls, i.e., 1st/2nd versus 3rd trimesters (105 women), and during pregnancy versus after delivery (289 women). HPV was assessed using highly sensitive PCR assays. Prevalence of HPV and HIV infections at baseline were 60.0% and 7.3%, respectively. HPV16 and 18 were detected in 8.4% and 5.8%, respectively, i.e., less frequently than HPV51 (8.7%) and 52 (12.1%). At follow‐up new HPV infections were detected in 42.9% of women between the 1st/2nd and 3rd trimesters, and 38.1% between pregnancy and delivery, but 50.4% and 71.8% of HPV infections, respectively, cleared, leaving HPV prevalence unchanged in the different periods. Prevalence of cytological abnormalities diminished after delivery (from 21.2% to 12.4%). Presence of genital warts and sexually transmitted infections other than HPV were the strongest risk factors for prevalent or incident HPV infection. Clearance was lower among HIV‐positive women. In conclusion, HPV prevalence was high in primiparous women in Uganda, but pregnancy did not seem to be a period of special vulnerability to the infection. © 2008 Wiley‐Liss, Inc.
Validation of quality indicators for radical prostatectomy
Authors: Chan Ellen O.M. , Groome Patti A. , Siemens D. Robert
Published: August 2008

The feasibility and validity of proposed radical prostatectomy quality indicators has not been well studied. We assessed indicator availability from treating charts. We tested the convergent construct validity of a modified subset that were available from this information source by correlating them to hospital prostatectomy volume, a variable repeatedly associated with the quality of surgical care. The study population consisted of a stratified random sample of prostate cancer patients who were: (i) diagnosed between 1990 and 1998 in Ontario and (ii) treated by radical prostatectomy with curative intent within 6 months of diagnosis (n = 645). Of the 9 candidate quality indicators assessed, 4 were missing for 25–56% of study subjects and were not analyzed further. We discuss the implications of this missing information on feasibility of their use. For blood transfusions of 3 units or greater, length of hospital stay and use of non‐nerve‐sparing surgical technique, worse outcomes were generally apparent with decreasing hospital volume. Acute complication rates and positive surgical margin rates did not increase with decreasing hospital volume. We were able to demonstrate convergent construct validity for 3 quality indicators. Upon further validation, this readily available information may be applied to aid providers and quality councils to more effectively identify problems and guide change in the management of early prostate cancer. © 2008 Wiley‐Liss, Inc.
Sarkozy one year later: Is his mind on France, or Carla?
Authors: Rosener James D.
Published: August 2008

The inauguration of French President Nicolas Sarkozy in June 2007 was filled with optimism. Most French seemed ready to adopt badly needed reforms. But one year later, public support has eroded—from almost weekly tabloid stories about Sarkozy's new wife, Carla Bruni. © 2008 Wiley Periodicals, Inc.
Time to leave foreign stock markets?
Authors: Tokic Damir , Tokic Stijepko
Published: August 2008

International stock markets have significantly outperformed the U.S. stock market from 2005 to 2008. But will this continue?

The authors argue that international markets will hit their peak sometime this year—if they haven't already done so. The reason is that they will be dragged down by the anticipated U.S. recession.

And what should U.S. investors do? The authors have some prudent recommendations. © 2008 Wiley Periodicals, Inc.
MSINDO study of acid promoted dissolution of planar MgO and NiO surfaces
Authors: Simpson Darren J. , Bredow Thomas , Gerson Andrea R.
Published: August 2008

Despite the structural similarity, MgO is fast dissolving in low pH solution, whereas NiO is slow dissolving under the same conditions. In addition, the planar MgO (100) surface immediately reconstructs to form pits and protrusions, whereas this behavior has not been observed with NiO (100). Our previous study, using the semiempirical self‐consistent field molecular orbital (SCFMO) method MSINDO showed that it was possible for MgO dissolution but not NiO dissolution to occur via the migration of a metal‐oxygen pair to an ex situ position. However, we have now found a more energetically favorable and realistic dissolution mechanism involving the dissociation of a water molecule (adsorbed on a metal site) prior to migration. Products from this dissociation (H and OH) weaken adjacent metal‐oxygen bonds. Dissociation of a second adsorbed water molecule is required to complete the process. For both oxides, the energy barrier determined from the energy profile of the metal‐oxygen pair migration was found to be lower than the activation energy of water dissociation at the planar surface as reported in previous study. This would suggest that the dissociation of water molecules at the planar surface is ratedetermining in the surface restructuring step of dissolution. It was demonstrated that surface restructuring and dissolution of MgO is possible whereas highly improbable for NiO, in agreement with experimental observations. © 2008 Wiley Periodicals, Inc. J Comput Chem 2009
Identification of amyloidogenic peptide sequences using a coarse‐grained physicochemical model
Authors: Clarke Oliver J. , Parker Martin J.
Published: August 2008

Cross‐β amyloid is implicated in over 20 human diseases. Experiments suggest that specific sequence elements within amyloidogenic proteins play a major role in seeding amyloid formation. Identifying these seeding sequences is important for rationalizing the molecular mechanisms of amyloid formation and for elaborating therapeutic strategies that target amyloid. Theoretical techniques play an important role in facilitating the identification and structural characterization of putative seeding sequences; most amyloid species are not amenable to high resolution experimental structure techniques. In this study we have combined a coarse‐grained physicochemical protein model with a highly efficient Monte Carlo sampling technique to identify amyloidogenic sequences in four proteins for which respective experimental peptide fragmentation data exist. Peptide sequences were defined as amyloidogenic if the ensemble structure predicted for three interacting peptides described a stable and regular three‐stranded β‐sheet. For such peptides, free energies were calculated to provide a measure of amyloid propensity. The overall agreement between the experimental and predicted data is good, and we correctly identify several self‐recognition motifs proposed to define the cross‐β amyloid fibril architectures of two of the proteins. Our results compare very favorably with those obtained using atomistic molecular dynamics methods, though our simulations are 30–40 times faster. © 2008 Wiley Periodicals, Inc. J Comput Chem 2009