bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation of Highly Active 40 wt.% Pt on Multiwalled Carbon Nanotube by Improved Impregnation Method for Fuel Cell Applications
Authors: Rahsepar M. , Pakshir M. , Piao Y. , Kim H. 
Published: July 2012

Abstract40 wt.% Pt catalyst supported on multiwalled carbon nanotube (MWCNT) was successfully synthesized by using improved aqueous impregnation method. Catalysts were characterized by HR‐TEM, XRD, and X‐Ray photoelectron spectroscopy. Electrocatalytic performance of the catalyst materials was investigated by electrochemical half cell test measurements. According to the results of electrochemical measurements, synthesized Pt/MWCNT catalyst presented high electrochemical activity which is mostly due to high utilization of catalyst particles and good physical properties of MWCNT supporting material. It was revealed that, improved aqueous impregnation method has a satisfactory efficiency for production of Pt/MWCNT catalyst.
Major differences among chemopreventive organoselenocompounds in the sustained elevation of cytoprotective genes
Authors: Poerschke Robyn L. , Franklin Michael R. , Bild Andrea H. , Moos Philip J. 
Published: July 2012

AbstractCytoprotective enzyme elevation through the nuclear erythroid 2 p45‐related factor 2 (Nrf2)–Kelch‐like ECH‐associated protein 1/antioxidant response element pathway has been promulgated for cancer prevention. This study compares the redox insult and sustained cytoprotective enzyme elevation by organoselenocompounds and sulforaphane (SF) in lung cells. SF elicited a rise in reactive oxygen species (ROS) and drop in glutathione (GSH) at 2 h; nuclear accumulation of Nrf2 at 4 h; and a GSH rebound and elevation in NAD(P)H quinone oxidoreductase (NQO1), thioredoxin reductase (TR1), and glutamate–cysteine ligase (GCL) at 24 h. Selenocystine (SECY) elicited a similar 24 h response, despite lesser earlier time‐point changes. 2‐Cyclohexylselenazolidine‐4‐carboxylic acid effects were similar to SECY's but with a larger Nrf2 change and the largest 24 h increase in GSH, GCL, TR1, and NQO1 of any compound investigated. Selenomethionine elicited a similar acute rise in ROS, but lesser depletion of GSH, no 4 h increase in nuclear Nrf2, only minor 24 h elevations in TR1 and NQO1, and a GCL elevation insufficient to elevate GSH. © 2012 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:344–353, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.21417
Possible neuroprotective property of nicotinic acetylcholine receptors in association with predominant upregulation of glial cell line‐derived neurotrophic factor in astrocytes
Authors: Takarada Takeshi , Nakamichi Noritaka , Kawagoe Hirofumi , Ogura Masato , Fukumori Ryo , Nakazato Ryota , Fujikawa Koichi , Kou Miki , Yoneda Yukio 
Published: July 2012

AbstractThe underlying mechanisms are still unclear for the neuroprotective properties of nicotine to date, whereas we have shown functional expression of nicotinic acetylcholine receptors (nAChRs) responsible for the influx of extracellular Ca2+ in cultured rat cortical astrocytes. In this study, we investigated the possible involvement of astrocytic nAChRs in the neuroprotection by this agonist. Exposure to nicotine predominantly induced mRNA expression of glial cell line‐derived neurotrophic factor (GDNF) among the different neurotrophic factors examined in cultured astrocytes, in a manner sensitive to nAChR antagonists, nifedipine, and aCa2+ chelator. Nicotine significantly increased GDNF in a concentration‐dependent manner in cultured astrocytes but not in neurons or neural progenitors even at the highest concentration used. In cultured astrocytes, a transient increase was seen in the expression of mRNA and corresponding protein for GDNF during sustained exposure to nicotine for 24 hr. Cytotoxicity mediated by oxidative, calcium, mitochondrial, or endoplasmic reticulum stress was invariably protected against in cortical neurons cultured with conditioned medium from astrocytes previously exposed to nicotine, and preincubation with the anti‐GDNF antibody reduced the neuroprotection by conditioned medium from astrocytes exposed to nicotine. Intraperitoneal administration of nicotine transiently increased the number of cells immunoreactive for both GDNF and glial fibrillary acidic protein in rat cerebral cortex. These results suggest that astrocytic nAChRs play a role in the neuroprotection against different cytotoxins after predominant upregulation of GDNF expression through a mechanism relevant to the acceleration of extracellular Ca2+ influx in rat brain in a particular situation. © 2012 Wiley Periodicals, Inc.
Employee Turnover Intention Among Newcomers in Travel Industry
Authors: Kim Namhyun 
Published: July 2012

ABSTRACTThe continual high turnover rate in the tourism and hospitality industry is the most problematic managerial topic. Using a sample of 304 travel agency employees, this research aims to identify differences in turnover antecedents between newcomers from graduate school or other industries and newcomers from the same industry. The results suggest several differences in both newcomer groups. Supervisor support is an antecedent for veterans, whereas personnel management, prospects and job‐related factors are only significant for neophytes. External causes were revealed as the most significant antecedents in both groups, whereas co‐worker support was not significant for turnover intention in either group. Copyright © 2012 John Wiley & Sons, Ltd.
Tourism and Governance in Small Island Developing States (SIDS): The Case of Zanzibar
Authors: Sharpley Richard , Ussi Miraji 
Published: July 2012

ABSTRACTTourism in small island developing states (SIDS) has long been defined in terms of dependency. However, less attention has been paid to the role of the state in SIDS, particularly the extent to which it supports tourism as an agent of development. Therefore, the purpose of this paper is to consider the governance of tourism development in SIDS, specifically the extent to which the state may promote or hinder tourism‐related development. Drawing on research in Zanzibar, it reveals the ways in which poor governance has acted as a barrier to development through tourism, concluding that the state has an unwillingness to support tourism. Copyright © 2012 John Wiley & Sons, Ltd.
Competition Between Motion Constraint and Aggregation of Macromolecular Chains in Poly(vinyl methyl ether)/Poly(ethylene oxide) Aqueous Solution During Phase Transition
Authors: Yang Kun , Yang Yu Zhao , Hu Cheng Long , Huang Yun Yun , Zhang Wen Kai , Chen Xu Dong , Zhang Ming Qiu 
Published: July 2012

AbstractResonance light scattering (RLS) technique was applied to study macromolecular entanglements in highly dilute poly(vinyl methyl ether) (PVME)/poly(ethylene oxide) (PEO) solution during phase transition process. Temperature dependences of RLS intensities of PVME, PEO and PVME/PEO solutions were recorded. In addition, simulated temperature dependence of RLS intensity of PVME/PEO solution was drawn supposing there was no interaction between PEO and PVME. Comparison between the measured with the simulated results indicated that there were obvious differences in RLS intensities and transition temperatures. The present work proved the existence of entanglements during phase separation in highly dilute solution. Moreover, a model was proposed to describe the entanglement behavior.
Computational microstructure modeling to estimate progressive moisture damage behavior of asphaltic paving mixtures
Authors: Ban Hoki , Kim Yong‐Rak , Rhee Suk‐Keun 
Published: July 2012

SUMMARYThis paper presents a computational microstructure model to estimate the progressive moisture damage of multiphase asphaltic paving mixtures. Moisture damage because of water transport is incorporated with mechanical loading through a finite element method. To simulate nonlinear damage evolution in the mixtures, the model includes Fickian moisture diffusion, a cohesive zone model to simulate the gradual fracture process, and a degradation characteristic function to represent the reduction of material properties because of moisture infiltration. With the model developed, various parametric analyses are conducted to investigate how each model parameter affects the material‐specific moisture damage mechanism and damage resistance potential of the mixtures. Analysis results clearly demonstrate the significance of physical and mechanical properties of mixture components and geometric characteristics of microstructure for the better design of asphaltic paving mixtures and roadway structures. Copyright © 2012 John Wiley & Sons, Ltd.
PSA forms complexes with α1‐antichymotrypsin in prostate
Authors: Zhu Lei , Jäämaa Sari , af Hällström Taija M. , Laiho Marikki , Sankila Anna , Nordling Stig , Stenman Ulf‐Håkan , Koistinen Hannu 
Published: July 2012

AbstractBACKGROUNDPSA is the most useful prostate cancer marker. However, its levels are increased also in some non‐malignant conditions. In circulation, the majority of PSA is complexed with protease inhibitors, including α1‐antichymotrypsin (ACT). The proportion of the PSA‐ACT complex is higher in patients with prostate cancer than in controls without cancer. The expression of ACT has been shown to be higher in prostate cancer than in benign prostatic hyperplasia. However, results regarding the extent which PSA forms complexes within the prostate and whether there are differences in complex formation between normal and malignant prostatic tissue are inconsistent and limited.METHODSWe studied complex formation of PSA secreted by cultured human prostate tissues and in the tissue by in situ proximity ligation assay (PLA). Free, total and active PSA, and the PSA‐ACT complex were determined in tissue culture media by immunoassays, immunoblotting, and chromatographic methods.RESULTSThe majority of PSA in tissue culture medium was free and enzymatically active. However, a significant proportion (1.6 ± 0.5%) of immunoreactive PSA was found to be complexed with ACT. Complex formation was confirmed by in situ PLA, which showed more intense staining of PSA‐ACT in cancers with Gleason grade 3 than in adjacent benign tissues from the same patients.CONCLUSIONSThese results show that PSA forms complexes already within the prostate and that PSA‐ACT levels are increased in moderately differentiated prostate cancer tissue. This may explain, at least partially, why the ratio of serum PSA‐ACT to total PSA is increased in prostate cancer. Prostate 73: 219–226, 2013. © 2012 Wiley Periodicals, Inc.
Preferential adsorption of thermally activated oxygen onto annealed polycrystalline diamond films studied by high resolution electron energy and X‐ray photoelectron spectroscopies
Authors: Michaelson Sh. , Akhvlediani R. , Tkach L. , Hoffman A. 
Published: July 2012

AbstractIn this work the amount of adsorbed oxygen and its chemical bonding configuration to diamond surface were investigated by X‐ray photoelectron spectroscopy (XPS) and high resolution electron energy loss spectroscopy (HR‐EELS), correspondingly. Hot filament chemical vapor deposited polycrystalline diamond films with sub‐micron grain size have been exposed in situ to thermally activated atomic oxygen (AO) and annealed in ultra‐high vacuum (UHV) in the range of 600–1000 °C. XPS studies revealed that substantial oxidation of the diamond surface takes place at TA > 800 °C, most likely owing to partial hydrogen desorption occurring at this temperature. HR‐EELS revealed that the main constituents of the surface after exposure to AO are saturated and unsaturated hydrocarbon species and oxygen‐bonded fragments. Oxygen bonds to diamond surface in ether (COC), peroxide (COOC), and carbonyl (CO) bonding. HR‐EELS features comparison of hydrogenated and oxygen exposed diamond surface as a function of thermal annealing suggests enhanced reactivity of hydrogenated diamond (111) facets as compared to (100) ones.
Microarray with Micro‐ and Nano‐topographies Enables Identification of the Optimal Topography for Directing the Differentiation of Primary Murine Neural Progenitor Cells
Authors: Moe Aung Aung Kywe , Suryana Mona , Marcy Guillaume , Lim Sandy Keat , Ankam Soneela , Goh Jerome Zhi Wen , Jin Jing , Teo Benjamin Kim Kiat , Law Jaslyn Bee Khuan , Low Hong Yee , Goh Eyleen L. K. , Sheetz Michael P. , Yim Evelyn K. F. 
Published: July 2012

AbstractDuring development and tissue repair, progenitor cells are guided by both biochemical and biophysical cues of their microenvironment, including topographical signals. The topographical cues have been shown to play an important role in controlling the fate of cells. Systematic investigation of topographical structures with different geometries and sizes under the identical experimental conditions on the same chip will enhance the understanding of the role of shape and size in cell–topography interactions. A simple customizable multi‐architecture chip (MARC) array is therefore developed to incorporate, on a single chip, distinct topographies of various architectural complexities, including both isotropic and anisotropic features, in nano‐ to micrometer dimensions, with different aspect ratios and hierarchical structures. Polydimethylsiloxane (PDMS) replicas of MARC are used to investigate the influence of different geometries and sizes in neural differentiation of primary murine neural progenitor cells (mNPCs). Anisotropic gratings (2 μm gratings, 250 nm gratings) and isotropic 1 μm pillars significantly promote differentiation of mNPCs into neurons, as indicated by expression of β‐III‐tubulin (59%, 58%, and 58%, respectively, compared to 30% on the control). In contrast, glial differentiation is enhanced on isotropic 2 μm holes and 1 μm pillars. These results illustrate that anisotropic topographies enhance neuronal differentiation while isotropic topographies enhance glial differentiation on the same chip under the same conditions. MARC enables simultaneous cost‐effective investigation of multiple topographies, allowing efficient optimization of topographical and biochemical cues to modulate cell differentiation.
Effectiveness of WRF wind direction for retrieving coastal sea surface wind from synthetic aperture radar
Authors: Takeyama Yuko , Ohsawa Teruo , Kozai Katsutoshi , Hasager Charlotte Bay , Badger Merete 
Published: July 2012

ABSTRACTWind direction is required as input to the geophysical model function (GMF) for the retrieval of sea surface wind speed from a synthetic aperture radar (SAR) images. The present study verifies the effectiveness of using the wind direction obtained from the weather research and forecasting model (WMF) as input to the GMF to retrieve accurate wind fields in coastal waters adjacent to complex onshore terrain. The wind speeds retrieved from 42 ENVISAT ASAR images are validated based on in situ measurements at an offshore platform in Japan. Accuracies are also compared with cases using wind directions: the meso‐analysis of the Japan Meteorological Agency (MANAL), the SeaWinds microwave scatterometer on QuikSCAT and the National Center for Environmental Prediction final operational global analysis data (NCEP FNL).In comparison with the errors of the SAR‐retrieved wind speeds obtained using the WRF, MANAL, QuikSCAT and NCEP FNL wind directions, the magnitudes of the errors do not appear to be correlated with the errors of the wind directions themselves. In addition to wind direction, terrain factors are considered to be a main source of error other than wind direction. Focusing on onshore winds (blowing from the sea to land), the root mean square errors on wind speed are found to be 0.75 m s  − 1 (in situ), 0.96 m s  − 1 (WRF), 1.75 m s  − 1 (MANAL), 1.58 m s  − 1 (QuikSCAT) and 2.00 m s  − 1 (NCEP FNL), respectively, but the uncertainty is of the same order of magnitude because of the low number of cases. These results indicate that although the effectiveness of using the accurate WRF wind direction for the wind retrieval is partly confirmed, further efforts to remove the error due to factors other than wind direction are necessary for more accurate wind retrieval in coastal waters. Copyright © 2012 John Wiley & Sons, Ltd.
Trading wind energy on the basis of probabilistic forecasts both of wind generation and of market quantities
Authors: Zugno M. , Jónsson T. , Pinson P. 
Published: July 2012

ABSTRACTWind power is not easily predictable and non‐dispatchable. Nevertheless, wind power producers are increasingly urged to participate in electricity market auctions in the same manner as conventional power producers. The aim of this paper is to propose an operational strategy for trading wind energy in liberalized electricity markets and to assess its performance. At first, the so‐called optimal quantile strategy is revisited. It is proved that without market power, i.e. under the price‐taker assumption, this strategy maximizes expected market revenues. Forecasts of wind power production, of day‐ahead and real‐time market prices and of the system imbalance are inputs to this strategy. Subsequently, constraining of the bid that maximizes the expected revenues is proposed as a way to overcome the strategy's disregard of practical limitations and, at the same time, of risk. Two constraining techniques are introduced: constraining in the decision space and in the probability space. Finally, the trade of a wind power producer is simulated in a test case for the Eastern Danish (DK‐2) price area of the Nordic Power Exchange (Nord Pool) during a 10 month period in 2008. The results of the test case show the financial benefits of the aforementioned strategy as well as the consequent interaction with the electricity market. This study will support a demonstration in the framework of the EU project ANEMOS.plus. Copyright © 2012 John Wiley & Sons, Ltd.
Multi‐body modelling and analysis of a planet carrier in a wind turbine gearbox
Authors: Xing Y. , Moan T. 
Published: July 2012

ABSTRACTThere have been some recent efforts to numerically model and analyse the wind turbine gearbox. To date, much of the focus has been on increasing model refinement and demonstrating its added value. This paper takes a step back and examines in detail the modelling and analysis of an important wind turbine gearbox component, the planet carrier, in a multi‐body setting. The planet carrier studied in this work comes from the 750 kW wind turbine gearbox used in the National Renewable Energy Laboratory's Gearbox Reliability Collaborative project. The study is performed in two parts. First, the influence of subcomponents mated to the planet carrier in the gearbox assembly is investigated in detail. These components consist of the planet pins, bearings and the main shaft. In the second part of the study, the flexible body modelling of the planet carrier for use in multi‐body simulations is examined through the use of condensed finite element and multi‐body simulation models. Both eigenvalue analyses and time domain simulations are performed. Comparisons are made regarding the eigenfrequencies, categorized mode shapes and the maximum and minimum planet carrier rim deflections from the time domain simulations. The mode shapes are categorized into seven distinct deformation patterns. An actual load case from the dynamometer tests, a 100% rated torque loading, is used in the time domain simulations. The results from this comprehensive study provide an insight into the proper modelling of a wind turbine planet carrier in a multi‐body setting. Copyright © 2012 John Wiley & Sons, Ltd.
Detrital zircon geochronology and sandstone provenance of basement Waipapa Terrane (Triassic–Cretaceous) and Cretaceous cover rocks (Northland Allochthon and Houhora Complex) in northern North Island, New Zealand
Authors: ADAMS C. J. , MORTIMER N. , CAMPBELL H. J. , GRIFFIN W. L. 
Published: July 2012

AbstractDetrital zircon U–Pb ages are reported for 14 sandstones of mainly Cretaceous age from the Northland Allochthon, Houhora Complex and Waipapa Terrane of northern North Island, New Zealand. Results from the Waipapa Terrane samples, selected from sequences in the Bay of Plenty, Coromandel Peninsula and Great Barrier Island, show that deposition continued into late Early Cretaceous time and, as in the Torlesse Composite Terrane, finally waned at c. 110–114 Ma. Upper Lower Cretaceous and Upper Cretaceous sedimentary successions in the Houhora Complex and Northland Allochthon have dominant sediment sources derived from local, contemporary volcanism, with a minor older contribution from the Murihiku Terrane to the west. As in eastern North Island, upper Upper Cretaceous sandstones lack major Albian magmatic components and their sources are solely in the Murihiku Terrane, and possibly the Western Province. We propose a Cretaceous palaeogeographic model that invokes a recently extinct orogen and a partially submerged continental borderland, dissected by rivers supplying submarine fans.
Enhancing the value of horizon scanning through collaborative review
Authors: Sutherland William J. , Allison Hilary , Aveling Rosalind , Bainbridge Ian P. , Bennun Leon , Bullock David J. , Clements Andy , Crick Humphrey Q. P. , Gibbons David W. , Smith Sarah , Rands Michael R. W. , Rose Paul , Scharlemann Jörn P. W. , Warren Martin S. 
Published: July 2012

AbstractThere is an increased appreciation of the need for horizon scanning: the identification and assessment of issues that could be serious in the future but have currently attracted little attention. However, a process is lacking to identify appropriate responses by policy makers and practitioners. We thus suggest a process and trial its applicability. Twelve environmental conservation organizations assessed each of 15 previously identified horizon scanning issues for their impact upon their organization and the urgency with which they should consider the issue. They also identified triggers that would result in changes in their scoring of the likely urgency and impact of the issues. This process enables organizations to identify priority issues, identify issues they can ignore until there are further developments, benchmark priorities across organizations and identify cross-organizational priorities that warrant further attention, so providing an agenda for collation of evidence, research and policy development. In this trial the review of responses by other organizations resulted in the upgrading of response by a substantial proportion of organizations for eight of the 15 issues examined. We suggest this approach, with the novel components of collaborative assessment and identification of triggers, could be adopted widely, both within conservation organizations and across a wider range of policy issues.