bluuebunny/crossref_metadata_2025_split huggingface dataset:
Growth by Liquid‐Injection MOCVD and Properties of HfO2 Films for Microelectronic Applications
Authors: Dubourdieu C. , Rauwel E. , Millon C. , Chaudouët P. , Ducroquet F. , Rochat N. , Rushworth S. , Cosnier V. 
Published: March 2006

AbstractThin films of HfO2 were deposited on (100)Si/SiO2 by liquid‐injection metal‐organic (MO)CVD using [Hf(OtBu)2(mmp)2] dissolved in octane as the precursor. A precise thickness control on the nanometer scale was obtained by controlling the volume of injected precursor solution. Films of thickness below 10 nm were studied by means of X‐ray reflectometry (XRR), attenuated total reflection infrared spectroscopy (ATR), and atomic force microscopy (AFM). Films are amorphous for deposition temperatures below 350 °C; they are polycrystalline at deposition temperature of 360 °C and above, except for ultrathin films. Under the deposition conditions used, the main crystalline phase is the monoclinic phase as shown by ATR. AFM reveals smooth surfaces for both amorphous and polycrystalline films. The equivalent oxide thickness measured in MOS structures depends linearly on the film's thickness, and a relative dielectric permittivity ϵr of 19 is obtained, which is consistent with that expected for the monoclinic phase of bulk HfO2. Leakage current densities of the order of 1×10–4 A cm–2 for films with a physical thickness of 3.1 nm are obtained. Rapid thermal annealing under ammonia reduces the fixed charges in the oxide (Qox < 1×1011 cm–2) as well as the interfacial charge density (Dit peak = 8×1010 eV–1 cm–2).
Are carrots as good as sticks? Ex Ante efficiency of a Swedish environmental subsidy programme
Authors: Johansson Maria Vredin 
Published: March 2006

AbstractWe evaluate the ex ante efficiency of a major Swedish investment subsidy programme, the ‘local investment programme’ (LIP). The LIP, effective between 1998 and 2002, had parallel purposes: to step up the pace at which Sweden transforms into an ecologically sustainable society and to reduce unemployment. During the programme period, c670 million were granted to different municipal projects. We find that the marginal LIP subsidy to the largest beneficial environmental variable, reductions of carbon dioxide, does not vary significantly over projects, implying that LIP subsidy was efficiently allocated for such reductions. The beneficial variable with largest economic significance was, however, the employment variable. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.
Synthesis, Structure, Electrochemistry, and Metal‐Atom Dynamics of Cyclopentadienyl Ferracarboranes
Authors: Herber Rolfe H. , Kudinov Alexander R. , Zanello Piero , Nowik Israel , Perekalin Dmitry S. , Meshcheryakov Vladimir I. , Lyssenko Konstantin A. , Corsini Maddalena , Fedi Serena 
Published: March 2006

AbstractA series of metallacarboranes, incorporating the CpFe fragment, were studied by electrochemical techniques, temperature‐dependent Mössbauer effect (ME) spectroscopy, and X‐ray diffraction. The compounds studied include the parent dicarbollide complex CpFeC2B9H11 (1) and its reduced form [1]–, the charge‐compensated ferradicarbollides 1‐Cp‐4‐L‐1,2,3‐FeC2B9H10 [L = SMe2 (2a), NMe3 (2b), py (2c)] and their methylated analogs 1‐Cp‐2,3‐Me2‐4‐SMe2‐1,2,3‐FeC2B9H8 (2d) and 1‐Cp*‐4‐SMe2‐1,2,3‐FeC2B9H10 (2e), the isomeric ferratricarbollides CpFeC3B8H11 (3a–c), and the amino‐substituted derivative 1‐Cp‐12‐tBuNH‐1,2,4,12‐FeC3B8H10 (3d). The ferradicarbollides 2a–e were synthesized by reactions of the charge‐compensated dicarbollide anions [9‐L‐7,8‐R2‐7,8‐C2B9H8]– (R = H, Me) with [(C5R5)Fe(MeCN)3]+ cations. The structures of 1, [NMe3Ph][1], and 2b were investigated by X‐ray diffraction. The ME spectroscopic study elucidated the relationship between the nature of the five‐membered carborane face coordinated to the metal center and the hyperfine interaction parameters of the Fe atom. Temperature‐dependent recoil‐free fraction studies yielded the root‐mean‐square‐amplitude‐of‐vibration (rmsav) of the metal atom over a wide temperature range, which proved to be in good agreement with crystallographic Ui,j data for 1 and 3a,b. Electrochemistry shows that the isomeric ferratricarbollides 3a–c undergo reversible oxidation to the corresponding FeIII derivatives at potential values higher, on average, by about 0.4 V than those of the charge‐compensated complexes 2a–c and by about 0.8 V than that of the parent ferradicarbollide [1]–. This result indicates the strong electron‐withdrawing ability of the extra carbon atom relative to that of the replaced boron atom. As a consequence of the shift of the HOMO–LUMO frontier orbitals to the high energy levels, the FeII/FeI reduction becomes accessible. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Aryl Ferrophites – A New Class of Ligands for Asymmetric Catalysis
Authors: Albrow Victoria E. , Blake Alexander J. , Fryatt Ross , Wilson Claire , Woodward Simon 
Published: March 2006

AbstractEnantiopure lithiated 1,2‐ferrocenes, [CpFe{1,2‐η5‐C5H3(Ar)(Li)}] (Ar = Ph, 4‐CF3C6H4, 1‐C10H7), react readily with PhOP(OR)2 to yield [CpFe{1,2‐η5‐C5H3(Ar)P(OR)2}] (R = Ph, 1,1′‐biphenyl‐based, 1,1′‐binaphthyl‐based) efficiently. Traditional routes to these species, involving the use of chlorophosphites ClP(OR)2 were found to be ineffective. These “ferrophite” ligands have been characterised by X‐ray crystallography (4 examples) and shown to be effective in both nickel‐catalysed addition of AlMe3 to PhCHO (up to 77 % ee) and copper(I)‐catalysed additions of organoaluminium reagents to enones (up to 92 % ee). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Tempo‐spatial covariance structure of lentil yield and water use efficiency from supplemental irrigation trials
Authors: Singh M. , Oweis T. , Pala M. , Sarker A. 
Published: March 2006

AbstractIn agricultural research conducted in dry areas, crop‐yield water use efficiency (WUE) is a measure used to evaluate the impacts of various agronomic factors on crop productivity. Agronomic management factors include supplemental irrigation (SI) and crop‐rotation systems, which are used to increase the sustainability of crop production systems. A study of lentil (Lens culinarisMedikus) was conducted in split‐plot experiments in randomized complete blocks, where planning date (PD) were assigned to main‐plots and SI to sub‐plots. Lentil was grown in rotation with durum wheat (i.e., lentil was grown 1 year and durum wheat the next, on the same plot of land) over a period of 4 years (1996/1997–1999/2000) at the research station of the International Center for Agricultural Research in the Dry Areas (ICARDA), at Tel Hadya, Syria. Spatial variability in the field trials and correlations between the plot errors arising over time were studied to examine their effects on the significance and precision of the estimates of the effects of PD and SI on yields (of both seed and total biomass) and WUE. The analyses revealed the presence of significant linear soil‐fertility trends within the fields and strongly auto‐correlated plot errors. When these trends were accounted for in the analysis of yield and WUE data, the estimates of the treatment effects had greater levels of significance and precision than when the trends were ignored. It is recommended that in agronomic field trials, such as lentil variety evaluation trials, one should identify the most appropriate spatial and temporal covariance structures and use these to draw statistical inferences about the effects of agronomic input factors. Copyright © 2006 John Wiley & Sons, Ltd.
A field method for the concurrent measurement of fine sediment content and embryo survival in artificial salmonid redds
Authors: Levasseur Mylène , Bérubé Francis , Bergeron Normand E. 
Published: March 2006

AbstractThe infiltration cube method presented in this paper allows concurrent field measurement of fine sediment content and embryo survival in an incubating environment reproducing, as closely as possible, the morphology and grain size composition of a natural salmonid redd. An infiltration cube is made up of a rectangular (30 cm square and 20 cm high) steel frame with no walls, which has a folded plastic bag attached to its base. Each infiltration cube is buried in the substrate using a procedure aimed at reproducing, as closely as possible, the construction and morpho‐sedimentological structure of a natural salmonid redd. Using a tripod installed on the river bed or at the surface of the ice, the infiltration cube method provides a quick, easy and robust way to pull relatively large samples (approximately 65 kg) out of underwater substrate even during tough winter field conditions. The absence of walls on the cube also precludes bias in infiltration rates by both allowing lateral sediment transport within substrate and preventing loss of fine particles during retrieval from underwater. Copyright © 2006 John Wiley & Sons, Ltd.
Thermoreversible laminin‐functionalized hydrogel for neural tissue engineering
Authors: Stabenfeldt Sarah E. , García Andrés J. , LaPlaca Michelle C. 
Published: March 2006

AbstractTraumatic injury to the central nervous system (CNS) triggers cell death and deafferentation, which may activate a cascade of cellular and network disturbances. These events often result in the formation of irregularly shaped lesions comprised of necrotic tissue and/or a fluid‐filled cavity. Tissue engineering represents a promising treatment strategy for the injured neural tissue. To facilitate minimally invasive delivery of a tissue engineered system, a thermoreversible polymer is an attractive scaffold candidate. We have developed a bioactive scaffold for neural tissue engineering by tethering laminin‐1 (LN) to methylcellulose (MC), a thermoresponsive hydrogel. The base MC chain was oxidized via sodium m‐periodate to increase MC tethering capacity. Protein immobilization was facilitated by a Schiff base reaction between primary amine groups on LN and the carbonyl groups of the oxidized MC chain. Immunoassays demonstrated tethering of LN at 1.6 ± 0.5 ng of LN per milligram of MC. Rheological measurements for different MC–LN constructs indicated MC composition‐ and MC treatment‐dependent effects on solution–gelation transition temperature. Cellular assays with primary rat cortical neurons demonstrated enhanced cell adhesion and viability on LN‐functionalized MC when compared with base and oxidized MC. This bioadhesive thermoresponsive scaffold may provide a robust delivery vehicle to injured CNS tissue for neural cell transplantation strategies. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Image‐guided and ‐monitored renal artery stenting using only MRI
Authors: Elgort Daniel R. , Hillenbrand Claudia M. , Zhang Shaoxiong , Wong Eddy Y. , Rafie Shervin , Lewin Jonathan S. , Duerk Jeffrey L. 
Published: March 2006

AbstractPurposeTo demonstrate the ability of a unique interventional MR system to be used safely and effectively as the only imaging modality for all phases of MR‐guided stent‐supported angioplasty.Materials and MethodsAn experimental disease model of renal stenosis was created in six pigs. An interventional MR system, which employed previously reported tools for real‐time catheter tracking with automated scan‐plane positioning, adaptive image parameters, and radial true–FISP imaging with steady‐state precession (True‐FISP) imaging coupled with a high‐speed reconstruction technique, was then used to guide all phases of the intervention, including: guidewire and catheter insertion, stent deployment, and confirmation of therapeutic success. Pre‐ and postprocedural X‐ray imaging was used as a gold standard to validate the experimental results.ResultsAll of the stent‐supported angioplasty interventions were a technical success and were performed without complications. The average postoperative residual stenosis was 14.9%. The image guidance enabled the stents to be deployed with an accuracy of 0.98 ± 0.69 mm. Additionally, using this interventional MRI system to guide renal artery stenting significantly reduces the procedure time, as compared to using X‐ray fluoroscopy.ConclusionThis study has clearly demonstrated the first successful treatment of renal artery stenting in an experimental animal model solely under MRI guidance and monitoring. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
MR‐visible coatings for endovascular device visualization
Authors: Unal Orhan , Li Junwei , Cheng Weiguo , Yu Hyuk , Strother Charles M. 
Published: March 2006

AbstractPurposeTo investigate the potential utility of magnetic resonance (MR)‐visible coatings for passive visualization of therapeutic endovascular devices such as catheters and guidewires.Materials and MethodsUsing a multistep coating process, gadolinium‐based coatings were applied to commercially available off‐the‐shelf catheters and guidewires. These coated devices were imaged in phantoms made of fat‐free yogurt, saline, and whole blood and also in live canine aorta on a 1.5‐T cardiovascular MR scanner using T1‐weighted two‐dimensional radiofrequency (RF)‐spoiled gradient‐recalled echo, two‐dimensional spin echo, and three‐dimensional RF‐spoiled gradient‐recalled echo techniques.ResultsCommercially available off‐the shelf catheters (4, 5, and 6 French) and guidewires (0.038 inch) were clearly visualized in all phantoms and canine aorta and the coatings proved to be durable and imageable without degradation in signal intensity up to 24 hours. MR‐visible coatings address some of the shortcomings that have previously limited the role of MR as a guidance tool.ConclusionBoth in vitro and in vivo visualization of therapeutic endovascular devices coated with MR‐visible coatings are found to be clinically viable. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Multicontrast black‐blood MRI of carotid arteries: Comparison between 1.5 and 3 tesla magnetic field strengths
Authors: Yarnykh Vasily L. , Terashima Masahiro , Hayes Cecil E. , Shimakawa Ann , Takaya Norihide , Nguyen Patricia K. , Brittain Jean H. , McConnell Michael V. , Yuan Chun 
Published: March 2006

AbstractPurposeTo compare black‐blood multicontrast carotid imaging at 3T and 1.5T and assess compatibility between morphological measurements of carotid arteries at 1.5T and 3T.Materials and MethodsFive healthy subjects and two atherosclerosis patients were scanned in 1.5T and 3T scanners with a similar protocol providing transverse T1‐, T2‐, and proton density (PD)‐weighted black‐blood images using a fast spin‐echo sequence with single‐ (T1‐weighted) or multislice (PD‐/T2‐weighted) double inversion recovery (DIR) preparation. Wall and lumen signal‐to‐noise ratio (SNR) and wall/lumen contrast‐to‐noise ratio (CNR) were compared in 44 artery cross‐sections by paired t‐test. Interscanner variability of the lumen area (LA), wall area (WA), and mean wall thickness (MWT) was assessed using Bland‐Altman analysis.ResultsWall SNR and lumen/wall CNR significantly increased (P < 0.0001) at 3T with a 1.5‐fold gain for T1‐weighted images and a 1.7/1.8‐fold gain for PD‐/T2‐weighted images. Lumen SNR did not differ for single‐slice DIR T1‐weighted images (P = 0.2), but was larger at 3T for multislice DIR PD‐/T2‐weighted images (P = 0.01/0.03). The LA, WA, and MWT demonstrated good agreement with no significant bias (P 0.5), a coefficient of variation (CV) of <10%, and intraclass correlation coefficient (ICC) of >0.95.ConclusionThis study demonstrated significant improvement in SNR, CNR, and image quality for high‐ resolution black‐blood imaging of carotid arteries at 3T. Morphologic measurements are compatible between 1.5T and 3T. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Potential mechanisms for astrocyte‐TIMP‐1 downregulation in chronic inflammatory diseases
Authors: Gardner Jessica , Borgmann Kathleen , Deshpande Muralidhar S. , Dhar Alok , Wu Li , Persidsky Raisa , Ghorpade Anuja 
Published: March 2006

AbstractThe pathogenesis of many neurodegenerative disorders, including human immunodeficiency virus (HIV)‐1 associated dementia, is exacerbated by an imbalance between matrix metalloproteinases (MMPs) and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs). In the context of disease, TIMP‐1 has emerged as an important multifunctional protein capable of regulating inflammation. We previously reported differential TIMP‐1 expression in acute versus chronic activation of astrocytes. This study investigates possible mechanisms underlying TIMP‐1 downregulation in chronic neuroinflammation. We used interleukin (IL)‐1β as a model pro‐inflammatory stimulus and measured TIMP‐1 binding to extracellular matrix, cell death, receptor downregulation, TIMP‐1 mRNA stability and transcriptional regulation in activated astrocytes. TIMP‐1 remained localized to the cell body or was secreted into the cell supernatant. DNA fragmentation ELISA and MTT assay showed that prolonged IL‐1β activation of astrocytes induced significant astrocyte death. In acute and chronic IL‐1β‐activated astrocytes, IL‐1 receptor levels were not significantly different. TIMP‐1 mRNA stability was measured in astrocytes and U87 astroglioma cells by real‐time PCR, and TIMP‐1 promoter activation was studied using TIMP‐1‐luciferase reporter constructs in transfected astrocytes. Our results indicated that TIMP‐1 expression is regulated through multiple mechanisms. Transcriptional control and loss of mRNA stabilization are, however, the most likely primary contributors to chronic downregulation of TIMP‐1. These data are important for unraveling the mechanisms underlying astrocyte responses during chronic neuroinflammation and have broader implications in other inflammatory diseases that involve MMP/TIMP imbalance. © 2006 Wiley‐Liss, Inc.
Stable expression of a neuronal dopaminergic progenitor phenotype in cell lines derived from human amniotic fluid cells
Authors: McLaughlin David , Tsirimonaki Emmanouella , Vallianatos George , Sakellaridis Nikolaos , Chatzistamatiou Theofanis , Stavropoulos‐Gioka Catherine , Tsezou Aspasia , Messinis Ioannis , Mangoura Dimitra 
Published: March 2006

AbstractCells from human amniotic fluid derived from the fetus are considered a source of multipotent cells. Their properties have not been fully exploited, partially because unlike other embryonic sources such as embryonic stem (ES) cells, cell lines from amniocentesis samples have not been generated. We have established and characterized the properties of eight individual cell lines. Flow cytometry using several cell surface markers showed that all cell lines generated consisted of homogeneous populations that lack HLAII antigenicity. Using a combination of immunocytochemistry, Western blotting, and RT‐PCR, we found weak expression of Oct4 and nestin and strong expression of tubulin‐βIII, MAP2, and tau. Specific markers for cholinergic, (nor)adrenergic, and GABAergic neurons or glia were weakly expressed or absent, whereas expression of factors implicated in early induction of dopaminergic neurons, TGF‐β3 and β‐catenin were present. Further analysis showed strong expression of EN‐1, c‐RET, PTX3, and NURR1 essential for induction and survival of midbrain dopaminergic neurons, TH, AADC, and VMAT2 components of dopamine synthesis and secretion, and syntaxin1A and SNAP‐25 necessary for neurotransmitter exocytosis. This phenotype was retained throughout passages and up to the current passage 36. Expression of neuronal and dopaminergic markers in individual AF cell lines was comparable to expression in neurons induced from ES cells and in IMR‐32 and SH‐SY5Y neuroblastomas. Our data show that cell lines can be derived from subcultures of amniocentesis, and are primarily composed of a population of progenitors with a phenotype similar to that of committed mesencephalic dopaminergic neurons. © 2006 Wiley‐Liss, Inc.
Polyethylene glycol treatment after traumatic brain injury reduces β‐amyloid precursor protein accumulation in degenerating axons
Authors: Koob Andrew O. , Borgens Richard B. 
Published: March 2006

AbstractPolyethylene glycol (PEG; 2,000 MW; 30% v/v) is a nontoxic molecule that can be injected intravenously and possesses well‐documented neuroprotective properties in the spinal cord of the guinea pig. Recent studies have shown that intravenous PEG can also enter the rat brain parenchyma after injury and repair cellular membrane damage in the region of the corpus callosum. Disrupted anterograde axonal transport and resulting β‐amyloid precursor protein (APP) accumulation are byproducts of traumatic axonal injury (TAI) in the brain. APP accumulation indicates axonal degeneration as a result of axotomy, a detriment that can lead to cell death. In this study, we show that PEG treatment can eliminate APP accumulation in specific brain areas of rats receiving TAI. Six areas of the brain were analyzed: the medial cortex, hippocampus, lateral cortex, thalamus, medial lemniscus, and medial longitudinal fasciculus. Increased APP expression after injury was abolished in the thalamus and reduced in the medial longitudinal fasciculus by PEG treatment. In all remaining areas except for the lateral cortex, APP expression was not increased between injured and uninjured brains, indicating that damage was undetected in those brain areas in this study. © 2006 Wiley‐Liss, Inc.
Increased axonal mitochondrial activity as an adaptation to myelin deficiency in the Shiverer mouse
Authors: Andrews Helen , White Kathryn , Thomson Christine , Edgar Julia , Bates David , Griffiths Ian , Turnbull Douglass , Nichols Philip 
Published: March 2006

AbstractAxonal pathology in multiple sclerosis (MS) has been described for over a century, but new insights into axonal loss and disability have refocused interest in this area. There is evidence of oxidative damage to mitochondrial DNA in chronic MS plaques, suggesting that mitochondrial failure may play a role in MS pathology. We propose that in the chronic absence of myelin the maintenance of conduction relies partially on an increase in mitochondria to provide energy. This increased energy requirement also promotes reactive oxygen species (ROS), because most intraaxonal ROS are generated by mitochondria. If antioxidant defenses are overwhelmed by an excess of ROS, this may result in damage to the axon. Our aim was to investigate whether a chronic lack of myelin results in adaptive changes involving mitochondria within the axon. We investigated this in the shiverer mouse. This myelin basic protein gene mutant provides a model of how adult central nervous system (CNS) axons cope with the chronic absence of a compact myelin sheath. Cytochrome c histochemistry demonstrated a twofold increase in mitochondrial activity in white matter tracts of shiverer, and electron microscopy confirmed a significantly higher number of mitochondria within the dysmyelinated axons. Our data demonstrate that there are adaptive changes involving mitochondria occurring within CNS axons in shiverer mice in response to a lack of myelin. This work contributes to our understanding of the adaptive changes occurring in response to a lack of myelin in a noninflammatory environment similar to the situation seen in chronically demyelinated MS plaques. © 2006 Wiley‐Liss, Inc.