bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theoretical investigation of the inhibition of corrosion by some triazole Schiff bases
Authors: Awad M. K. , Issa R. M. , Atlam F. M. 
Published: June 2009

AbstractAn examination of quantum chemical and corrosion inhibition studies is carried out to investigate whether any clear links exist between the results of quantum chemical calculations and the experimental inhibition efficiencies. The influence of the investigated triazole Schiff bases, (benzylidine amino) triazole (a), 4‐hydroxy 3‐(benzylidine amino) triazole (b), 2‐hydroxy 3‐(benzylidine amino) triazole (c), and 2‐ hydroxy 3‐(naphthylidine amino) triazole (d) on the inhibition of corrosion of the metal surfaces are studied by density functional theory at the B3LYP/6‐31G level. The calculated quantum chemical parameters correlated to the inhibition efficiency are, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), the separation energy (ΔE), the dipole moment (µ), the softness (σ), the total negative charge on the whole molecule (TNC), the total charge on the azo‐methine moiety, the molecular volume (Vi), and the total energy (TE). A good correlation between the quantum chemical parameters and the experimental inhibition efficiency is found. High inhibition efficiency for corrosion inhibitors can be achieved by controlling their electronic and structural properties.
Performance of Cu and Cu‐Zn alloy in the Arabian Gulf environment
Authors: Saricimen H. , Quddus A. , Ahmad A. , Aksakal A. , Siddique T. A. , Ul‐Hamid A. 
Published: June 2009

AbstractCorrosion performance of copper and brass coupons during 15 month exposure in atmosphere, underground and splash zone conditions was undertaken at Khaleej Mardumah test site located in the industrial/coastal city of Jubail along the Arabian Gulf coast, Saudi Arabia. The environmental indicators such as soil, groundwater, seawater, and air particulate samples were assessed. The exposed corrosion coupons were examined by scanning electron microscopy (SEM) coupled with energy dispersive X‐ray spectroscopy (EDS), X‐ray diffraction (XRD) and X‐ray fluorescence (XRF) to identify the corrosion products and study their surface morphology. Corrosion rate was determined by weight loss method. The experimental results indicated that a high degree of variation in temperature and humidity in this region combined with high chloride and sulfate concentrations was primarily responsible for the corrosion of copper and brass at Khaleej Mardumah test site. Underground environment was the most corrosive to both copper and brass coupons studied, followed by splash zone. Corrosion rates were found to range from 4.29 to 10.84 µm/y for copper and from 2.47 to 29.31 µm/y for brass. Corrosion rates of copper and brass obtained in this study are also compared with those reported for other locations worldwide.
Analysis of different factors affecting cathodic protection for deep well casings
Authors: Metwally I. A. , Al‐Badi A. H. 
Published: June 2009

AbstractThis paper introduces a comparative theoretical investigation of the conventional cathodic protection (CP) and the pulse cathodic protection (PCP) systems to show how both of them behave under different operating conditions. The effectiveness of the PCP system is also highlighted for a typical large‐scale configuration as well as some field measurements have been carried out. The performance of PCP system has been analyzed in the light of getting better protection‐current distribution along the protected well casing at reduced anode current together with reducing the stray current (corrosion) at any nearby unprotected structure(s). Many factors have been investigated to show their effects on the performance of the CP system, namely, soil resistivity, voltage pulse waveform and frequency, and multi‐layer soil. In addition, the performance of both the conventional CP and the PCP systems has been compared to that when utilizing unused/abandoned well casing as anode energized by the conventional CP system. The PCP system shows better performance than that of the conventional CP, and a similar performance at high soil resistivity to that when using unused/abandoned well casing. On the other hand, the utilization of the unused/abandoned well casing gives superior performance, especially at low soil resistivities, where the protection‐current profiles of both the conventional CP and the PCP systems decay sharply.
Pore solution of concrete: The equilibrium of bound and free chloride
Authors: Tritthart J. 
Published: June 2009

AbstractThe chloride threshold values of concrete specified in the regulations are based on the total chloride content of the concrete. As only the chloride dissolved in the pore solution can initiate corrosion, the investigations focused on the chloride concentration of the pore solution. It was further investigated if the answer to the question — why chloride is taken up by concrete exposed to de‐icing salts relatively quickly but is only slowly ‘washed out’ during summer — can be found in the chloride/cement‐binding interactions. The results showed that the residual chloride concentration depends in particular on the OH− concentration of the pore solution. The results further showed that the same binding mechanisms exist regardless of whether the chloride is mixed to the cement or added subsequently via diffusion. Other results suggested that one of the causes why chloride is taken up faster than it is washed out from concrete by rainwater are the binding interactions as well. As regards the assessment of the corrosion risk, the results showed that both the Cl− concentration and the Cl−/OH− ratio of the pore solution varied between samples made of the same cement and containing the same total chloride content. These results illustrate very well that a certain total chloride content alone is not a suitable criterion for the assessment of corrosion risk and that other factors of influence must be taken into account as well.
Cortical hypometabolism assessed by a metabolic ratio in Parkinson's disease primarily reflects cognitive deterioration—[18F]FDG‐PET
Authors: Liepelt Inga , Reimold Matthias , Maetzler Walter , Godau Jana , Reischl Gerald , Gaenslen Alexandra , Herbst Heinz , Berg Daniela 
Published: June 2009

AbstractIn Parkinson's disease patients with cognitive deterioration, regional cortical hypometabolism has been observed with [18F]fluorodeoxyglucose‐positron emission tomography (FDG‐PET). Our aim was to develop a robust method to subsume the overall degree of metabolic deterioration in Parkinson's disease by means of a single index and to investigate which of the clinical features correlates best with hypometabolism. Twenty‐two Parkinson's patients (10 demented) and seven controls underwent FDG‐PET. A metabolic index (mean relative uptake in typically affected regions) was calculated for each patient and compared with scores for cognition [Minimental State Examination (MMSE)], motor performance [Unified Parkinson's Disease Rating Scale (UPDRS III)” and behavior (Neuropsychiatric Inventory). In stepwise linear regression analysis, MMSE (P < 0.001) score showed the only significant effect. Estimated sensitivity and specificity for DSM‐IV diagnosis of dementia were high for the metabolic index (MI), with 91 and 100%. Taken together, the presented data indicate that cerebral hypometabolism in Parkinson's disease is primarily associated with cognitive impairment. © 2009 Movement Disorder Society
Characterizing pulmonary blood flow distribution measured using arterial spin labeling
Authors: Henderson A. Cortney , Prisk G. Kim , Levin David L. , Hopkins Susan R. , Buxton Richard B. 
Published: June 2009

AbstractThe arterial spin labeling (ASL) method provides images in which, ideally, the signal intensity of each image voxel is proportional to the local perfusion. For studies of pulmonary perfusion, the relative dispersion (RD, standard deviation/mean) of the ASL signal across a lung section is used as a reliable measure of flow heterogeneity. However, the RD of the ASL signals within the lung may systematically differ from the true RD of perfusion because the ASL image also includes signals from larger vessels, which can reflect the blood volume rather than blood flow if the vessels are filled with tagged blood during the imaging time. Theoretical studies suggest that the pulmonary vasculature exhibits a lognormal distribution for blood flow and thus an appropriate measure of heterogeneity is the geometric standard deviation (GSD). To test whether the ASL signal exhibits a lognormal distribution for pulmonary blood flow, determine whether larger vessels play an important role in the distribution, and extract physiologically relevant measures of heterogeneity from the ASL signal, we quantified the ASL signal before and after an intervention (head‐down tilt) in six subjects. The distribution of ASL signal was better characterized by a lognormal distribution than a normal distribution, reducing the mean squared error by 72% (p < 0.005). Head‐down tilt significantly reduced the lognormal scale parameter (p = 0.01) but not the shape parameter or GSD. The RD increased post‐tilt and remained significantly elevated (by 17%, p < 0.05). Test case results and mathematical simulations suggest that RD is more sensitive than the GSD to ASL signal from tagged blood in larger vessels, a probable explanation of the change in RD without a statistically significant change in GSD. This suggests that the GSD is a useful measure of pulmonary blood flow heterogeneity with the advantage of being less affected by the ASL signal from tagged blood in larger vessels. Copyright © 2009 John Wiley & Sons, Ltd.
A discrete filled function method for the optimal control of switched systems in discrete time
Authors: Feng Z. G. , Teo K. L. , Rehbock V. 
Published: June 2009

AbstractIn this paper, we consider the optimal control problem of discrete‐time switched systems. This problem is formulated as an optimization problem involving both continuous and discrete‐valued variables. It can be transformed into a discrete optimization problem. A metric in the space of switching sequences is introduced and an appropriate discrete filled function is constructed. Then, an algorithm that combines the discrete filled function method and a descent method is developed for solving this problem. For illustration, some numerical examples are solved. Copyright © 2009 John Wiley & Sons, Ltd.
MicroRNA expression profiling of human metastatic cancers identifies cancer gene targets
Authors: Baffa Raffaele , Fassan Matteo , Volinia Stefano , O'Hara Brian , Liu Chang‐Gong , Palazzo Juan P , Gardiman Marina , Rugge Massimo , Gomella Leonard G , Croce Carlo M , Rosenberg Anne 
Published: June 2009

AbstractSmall non‐coding microRNAs (miRNAs) contribute to cancer development and progression, and are differentially expressed in normal tissues and cancers. However, the specific role of miRNAs in the metastatic process is still unknown. To seek a specific miRNA expression signature characterizing the metastatic phenotype of solid tumours, we performed a miRNA microarray analysis on 43 paired primary tumours (ten colon, ten bladder, 13 breast, and ten lung cancers) and one of their related metastatic lymph nodes. We identified a metastatic cancer miRNA signature comprising 15 overexpressed and 17 underexpressed miRNAs. Our results were confirmed by qRT‐PCR analysis. Among the miRNAs identified, some have a well‐characterized association with cancer progression, eg miR‐10b, miR‐21, miR‐30a, miR‐30e, miR‐125b, miR‐141, miR‐200b, miR‐200c, and miR‐205. To further support our data, we performed an immunohistochemical analysis for three well‐defined miRNA gene targets (PDCD4, DHFR, and HOXD10 genes) on a small series of paired colon, breast, and bladder cancers, and one of their metastatic lymph nodes. We found that the immunohistochemical expression of these targets significantly follows the corresponding miRNA deregulation. Our results suggest that specific miRNAs may be directly involved in cancer metastasis and that they may represent a novel diagnostic tool in the characterization of metastatic cancer gene targets. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Improvement of diencephalic syndrome after partial surgery of optic chiasm glioma
Authors: Marec‐Berard Perrine , Szathmari Alexandru , Conter Cécile , Mottolese Carmine , Berlier Pascale , Frappaz Didier 
Published: June 2009

AbstractA 10‐month‐old male presented with sudden growth failure and cachexia. MRI showed a chiasma of the hypothalamic mass. Biopsy was avoided due to operative risks. Three cycles of chemotherapy were given, resulting in stable disease on MRI, but growth failure despite attempts at enteral feeding. Surgical biopsy was then performed. A 30% tumor reduction was observed on post‐operative imaging. Pathological examination revealed a pilocytic astrocytoma. After surgery, the child gained weight and his growth curve returned to normal. Enteral feeding was discontinued. After 4‐year of follow‐up, neurological development remains normal, with no residual or endocrine abnormalities. Pediatr Blood Cancer 2009;53:502–504. © 2009 Wiley‐Liss, Inc.
Bead‐based multiplexed immunoassays to identify new biomarkers in maternal serum to improve first trimester Down syndrome screening
Authors: Koster M. P. H. , Pennings J. L. A. , Imholz S. , Rodenburg W. , Visser G. H. A. , de Vries A. , Schielen P. C. J. I. 
Published: June 2009

AbstractObjectivesTo identify new discriminative biomarkers for Down syndrome (DS) pregnancies using a bead‐based multiplexed immunoassay, and to use the newly identified biomarkers to construct a prediction model for non‐invasive DS screening.MethodsMaternal serum samples of 14 DS pregnancies and 15 matched controls were analyzed with a bead‐based multiplexed immunoassay containing immunoassays for 90 different analytes. Potential biomarkers were selected on the basis of concentration fold ratios between DS and control samples. For these markers and the current screening markers (pregnancy‐associated plasma protein‐A, PAPP‐A; free beta subunit of human chorion gonadotrophin (fβ‐hCG) and nuchal translucency) prediction values were obtained and used to calculate detection rates (DR) at a 5% false positive rate.ResultsSeven potential biomarkers of which the fold ratio exceeded 1.3 or −1.3 were selected for further analysis. All 14 DS cases in this study were detected using the combination of all currently used and newly identified markers. The modelled DR for all markers extrapolated to the general pregnant population was 82.5%, compared to a modelled DR of 56.2% for the current screening markers.ConclusionThis study demonstrates the possibility of improving the performance of the current first‐trimester DS screening by addition of new biomarkers, which were identified using bead‐based multiplexed immunoassays. Copyright © 2009 John Wiley & Sons, Ltd.
Social relationships in schizophrenia: A review
Authors: Stevens Amy Kingston , McNichol Judith , Magalhaes Lilian 
Published: June 2009

AbstractDifficulties with social occupations are among the most common for individuals with schizophrenia. The deficits related to social functioning have been shown to decrease the quality of life (QOL) and life satisfaction for individuals in this population. A critical review of the literature was completed in order to examine the factors that effect and impact social engagement, QOL and life satisfaction for individuals with schizophrenia. A comprehensive search of the CINAHL, PsycINFO and PubMed databases was conducted for articles published during the period of 1997–2007. From 156 peer‐reviewed articles meeting the search criteria, 41 were selected for analysis and included in the review. The main factors effecting QOL and life satisfaction that emerged from the literature include the following: interpersonal relationship status, employment status, effects of stigma, neuro‐cognitive skills and functioning, as well as effectiveness of interventions. The review suggests that individuals with a diagnosis of schizophrenia experience decreased QOL and social satisfaction in social relationships as a result of these factors. Copyright © 2009 John Wiley & Sons, Ltd.
The impacts of thawing permafrost on the chemistry of lakes across the subarctic boreal‐tundra transition, Mackenzie Delta region, Canada
Authors: Kokelj S. V. , Zajdlik B. , Thompson M. S. 
Published: June 2009

AbstractIn the lake‐rich tundra uplands east of the Mackenzie Delta, almost one in ten lakes has been affected by retrogressive thaw slumping. In this study, we assessed water chemistry for 34 slump‐affected and 39 undisturbed upland lakes across this region and found that environmental factors typically evoked to explain variation in tundra lake water quality including surficial geology and proximity to the treeline or coast were subordinate to the main driver, permafrost degradation. Thaw slump‐affected lakes had elevated ionic concentrations and water clarity in comparison with undisturbed lakes. The strength of the ionic impact was positively associated with the proportion of catchment affected by slumping and inversely related to disturbance age. Slumping did not have a significant effect on total organic carbon (TOC) concentrations, although water clarity increased significantly with decreasing age of disturbance. In lakes undisturbed by slumping, fire‐induced active‐layer deepening had a detectable influence on lake water ionic strength. Surficial deposits influenced TOC concentrations with the highest concentrations and colour in undisturbed lakes with lacustrine catchments. In a warming Arctic, thermokarst processes may increase in importance as a driver of ionic chemistry and optical properties of small lakes and ponds, and shifts in aquatic food webs can be anticipated. Copyright © 2009 John Wiley & Sons, Ltd. and Her Majesty the Queen in right of Canada.
Output feedback second‐order sliding mode control of the cart on a beam system
Authors: Sankaranarayanan V. , Mahindrakar Arun D. , Abhilash P. M. 
Published: June 2009

AbstractWe propose an output feedback second‐order sliding mode controller to stabilize the cart on a beam system. A second‐order sliding mode controller is designed using a Lyapunov function‐based switching surface and finite‐time controllers, while the state estimator is designed based on the Luenberger‐like observer. The proposed observer extends the applicability of Luenberger‐like observer to nonlinear systems that are not input–output linearizable, but can be approximately input–output linearized. The approximation is based on the physical property of the system, wherein certain terms in the total energy are neglected. Extensive numerical simulations validate the robustness of the proposed controller to parametric uncertainties using estimated states. Copyright © 2009 John Wiley & Sons, Ltd.
Surface excitation parameter for 12 semiconductors and determination of a general predictive formula
Authors: Pauly N. , Tougaard S. 
Published: June 2009

AbstractThe surface excitation parameter (SEP) is theoretically calculated for 12 semiconductors (GaN, GaP, GaSb, GaAs, InSb, InAs, InP, SiC, ZnSe, ZnS, Si and Ge) and for Ni (which is usually used as a reference in experiments) for electron energies between 300 eV and 3400 eV, and for angles between 0° and 70° to the surface normal. We use our previous definition of SEP, as the change in excitation probability, for an electron, caused by the presence of the surface in comparison with an electron moving the same distance in an infinite medium. The calculations are performed within the dielectric response theory by means of the QUEELS‐ε(k, ω)‐REELS software determining the energy‐differential inelastic electron scattering cross‐sections for reflection‐electron‐energy‐loss spectroscopy (REELS), and for which the only input is the dielectric function of the medium. By fitting to these SEP values as well as our previous ones, i.e. from 27 materials, including metals, oxides, polymers and semiconductors, we also establish a simple equation depending on the generalized plasmon energy and the energy band gap of the material which allows to estimate the SEP when the dielectric function is not available. Copyright © 2009 John Wiley & Sons, Ltd.
Properties of Au nanolayers on polyethyleneterephthalate and polytetrafluoroethylene
Authors: Slepička P. , Kolská Z. , Náhlík J. , Hnatowicz V. , Švorčík V. 
Published: June 2009

AbstractGold nanolayers deposited by sputtering on polytetrafluoroethylene (PTFE) and polyethyleneterephthalate (PET) films were studied in this work. The influence of sputtering time on the layer thickness, surface morphology and roughness was determined by various methods (i.e. atomic absorption spectroscopy, focused ion beam and scanning electron microscopy). Sheet resistance and concentration and mobility of free charge carriers in Au nanolayers were determined using the Van der Pauw method. Surface morphology was determined using atomic force microscopy (AFM). After gold deposition on PET, the surface roughness increases and the surface morphology changes in contrast with PTFE coated under the same conditions. With the increasing sputtering time, the layer resistance decreases rapidly for both polymer substrates. Electrically continuous coverage is achieved for the gold layer with an average thickness of ca 4 nm for PET and ca 5 nm for PTFE. Continuous layers on both polymers exhibit the same concentration of free charge carriers. Lower mobility of the charge carriers was found on rougher Au/PTFE. Copyright © 2009 John Wiley & Sons, Ltd.
In vivo quantification of regional dopamine‐D3 receptor binding potential of (+)‐PHNO: Studies in non‐human primates and transgenic mice
Authors: Rabiner Eugenii A. , Slifstein Mark , Nobrega Jose , Plisson Christophe , Huiban Mickael , Raymond Roger , Diwan Mustansir , Wilson Alan A. , McCormick Patrick , Gentile Gabriella , Gunn Roger N. , Laruelle Marc A. 
Published: June 2009

AbstractExamination of dopamine‐D3 (D3) receptors with positron emission tomography (PET) have been hampered in the past by the lack of a PET ligand with sufficient selectivity for D3 over dopamine‐D2 (D2) receptors. The two types co‐localize in the brain, with D2 density significantly higher than D3, hence nonselective PET ligands inform on D2, rather than D3 status. [11C]‐(+)‐PHNO is a novel PET ligand with a preferential affinity for D3 over D2. We used the selective D3 antagonist, SB‐277011 to dissect regional fractions of the [11C]‐(+)‐PHNO signal attributable to D3 and D2 in primate brain. The results were compared with quantitative autoradiography with3H‐(+)‐PHNO in wild‐type, D2‐knock‐out, and D3‐knock‐out mice examined at baseline and following administration of SB‐277011. Both sets of results converged to indicate a predominant D3‐related component to (+)‐PHNO binding in extra‐striatal regions, with binding in the midbrain being entirely attributable to D3. The midbrain is thus an excellent target region to examine D3 receptor occupancy with [11C]‐(+)‐PHNO PET in vivo. Synapse 63:782–793, 2009. © 2009 Wiley‐Liss, Inc.