bluuebunny/crossref_metadata_2025_split huggingface dataset:
Capillary electrochromatographic testing of monolithic silica columns synthesized according to an experimental design approach
Authors: Wu Xiaoping , Mangelings Debby , Oita Iuliana , Tanret Indiana , Yan Chao , Heyden Yvan Vander 
Published: June 2011

AbstractMonolithic silica capillary columns synthesized following a three‐level design were evaluated for the electrochromatographic separation of acidic and neutral compounds. The influences of four factors in the sol–gel synthesis, i.e. the concentrations of tetramethylorthosilicate (TMOS) and PEG in the starting mixture, the gelation temperature and the silanization modifying time, on the electrochromatographic performance of the resulting C18‐silica capillary monoliths were studied. The considered responses were retention factor, resolution, symmetry factor, column efficiency, electrokinetic porosity and the equivalent length of the monolith. The four factors were varied to change the pore structure and the surface coverage with octadecyl moieties, resulting in nine stationary phases. The retentive properties of the columns were initially characterized with alkylbenzenes. Next, the separation for acetylsalicylic acid (ASA) and its related compounds was optimized and used to evaluate the performance of the nine stationary phases considering six responses. A compromise between the different responses was found around higher concentrations of tetramethylorthosilicate and PEG with a lower gelation temperature and a modifying time of 2 h. Column efficiencies up to 96 000 plates/m and resolutions above 1.9 were obtained for the acetylsalicylic acid separation, with a sufficient EOF to yield rapid analysis, which showed improvements over the center‐point stationary phase.
Charitable Partnerships among Travel and Tourism Businesses: Perspectives from Low‐Fares Airlines
Authors: Fenclova Emily , Coles Tim 
Published: June 2011

ABSTRACTResponsibility has been advocated as vital for the future management and governance of the sustainable tourism destinations, yet extensive empirical research of specific stakeholders is lacking. This paper addresses this knowledge gap by examining corporate philanthropy practices among low‐fares airlines. An analytical framework is developed and applied. Corporate philanthropy is practised more widely than may have been anticipated by the frills‐adverse, low‐fares business model. For studies of tourism, the paper points to the need for greater theoretical and conceptual urgency in research on corporate social responsibility and corporate philanthropy if future practical action at the destination level is to match current advocacy. Copyright © 2011 John Wiley & Sons, Ltd.
A Soluble High Molecular Weight Copolymer of Benzo[1,2‐b:4,5‐b′]dithiophene and Benzoxadiazole for Efficient Organic Photovoltaics
Authors: Nie Wanyi , MacNeill Christopher M. , Li Yuan , Noftle Ronald E. , Carroll David L. , Coffin Robert. C. 
Published: June 2011

AbstractThe synthesis and characterization of a soluble high molecular weight copolymer based on 4,8‐bis(1‐pentylhexyloxy)benzo[1,2‐b:4,5‐b′]dithiophene and 2,1,3‐benzoxadiazole is presented. High efficiency organic photovoltaic (OPV) devices comprised of this polymer and phenyl‐C71‐butyric acid methyl ester (PC71BM) were fabricated by additive processing with 1‐chloronapthalene (CN). When the active layer is cast from pristine chlorobenzene (CB), power conversion efficiencies (PCEs) average 1.41%. Our best condition—using 2% chloronapthalene as a solvent additive in CB—results in an average PCE of 5.65%, with a champion efficiency of 6.05%. magnified image
Self‐Assembled Single‐Crystal Polyaniline Microplates and Their Anisotropic Electrical Transport Property
Authors: Yan Yong , Fang Jin , Zhang Yajie , Fan Huili , Wei Zhixiang 
Published: June 2011

AbstractSelf‐assembly of two‐dimensional (2D) structures from functional molecules is of great scientific importance. Herein, using a typical linear conducting polymer, polyaniline as building blocks, 2D single crystalline microplates are successively produced. The structure of 2D microplates is clearly defined by selected area electron diffraction, X‐ray diffraction, and Raman spectroscopy. Owing to the anisotropic arrangement of linear conjugated PANI molecules, the microplate shows a typical anisotropic electrical transport property. magnified image
Magneto‐sensitive Elastomers in a Homogeneous Magnetic Field: A Regular Rectangular Lattice Model
Authors: Ivaneyko Dmytro , Toshchevikov Vladimir P. , Saphiannikova Marina , Heinrich Gert 
Published: June 2011

AbstractA theory of mechanical behaviour of the magneto‐sensitive elastomers is developed in the framework of a linear elasticity approach. Using a regular rectangular lattice model, different spatial distributions of magnetic particles within a polymer matrix are considered: isotropic, chain‐like and plane‐like. It is shown that interaction between the magnetic particles results in the contraction of an elastomer along the homogeneous magnetic field. With increasing magnetic field the shear modulus, G, for the shear deformation perpendicular to the magnetic field increases for all spatial distributions of magnetic particles. At the same time, with increasing magnetic field the Young's modulus, E, for tensile deformation along the magnetic field decreases for both chain‐like and isotropic distributions of magnetic particles and increases for the plane‐like distribution of magnetic particles. magnified image
Anhedonia in Parkinson's disease: A systematic review of the literature
Authors: Assogna Francesca , Cravello Luca , Caltagirone Carlo , Spalletta Gianfranco 
Published: June 2011

AbstractAnhedonia, defined as lowered ability to experience physical or social pleasure, is a key symptom of several psychiatric illnesses. In this systematic review, we aimed to evaluate the role of anhedonia in Parkinson's Disease and its relationships with other clinical characteristics, dopamine dysfunction, and antiparkinsonian therapy. The database was selected using PubMed Services. Relevant journals were hand‐searched, and the bibliographies of all the important articles were scrutinized to find additional publications. Fifteen studies assessed the topic of anhedonia in Parkinson's disease from 1984 to 2009 and mainly described it as a core symptom of depression in patients with Parkinson's disease. Some studies investigated the relationship between anhedonia and neuropsychological symptoms and found correlations with frontal lobe functions. Reports on the relationship between anhedonia and illness severity or motor symptoms are rather inconclusive. No definitive conclusions can be drawn because few studies have been published on this topic. Nevertheless, some evidence suggests that in Parkinson's disease anhedonia is a secondary phenomenon linked to depression, apathy severity, and frontal lobe dysregulation and that it could respond to antiparkinsonian treatment. Future studies of larger samples of patients are strongly required to definitively clarify the relationship between anhedonia and other clinical features, such as depression, anxiety, apathy, cognition, and motor status. Furthermore, more reliable tools and validated diagnostic criteria are necessary to assess anhedonia in patients with Parkinson's disease. © 2011 Movement Disorder Society
Size‐optimized 32‐channel brain arrays for 3 T pediatric imaging
Authors: Keil Boris , Alagappan Vijay , Mareyam Azma , McNab Jennifer A. , Fujimoto Kyoko , Tountcheva Veneta , Triantafyllou Christina , Dilks Daniel D. , Kanwisher Nancy , Lin Weili , Grant P. Ellen , Wald Lawrence L. 
Published: June 2011

AbstractSize‐optimized 32‐channel receive array coils were developed for five age groups, neonates, 6 months old, 1 year old, 4 years old, and 7 years old, and evaluated for pediatric brain imaging. The array consisted of overlapping circular surface coils laid out on a close‐fitting coil‐former. The two‐section coil former design was obtained from surface contours of aligned three‐dimensional MRI scans of each age group. Signal‐to‐noise ratio and noise amplification for parallel imaging were evaluated and compared to two coils routinely used for pediatric brain imaging; a commercially available 32‐channel adult head coil and a pediatric‐sized birdcage coil. Phantom measurements using the neonate, 6‐month‐old, 1‐year‐old, 4‐year‐old, and 7‐year‐old coils showed signal‐to‐noise ratio increases at all locations within the brain over the comparison coils. Within the brain cortex the five dedicated pediatric arrays increased signal‐to‐noise ratio by up to 3.6‐, 3.0‐, 2.6‐, 2.3‐, and 1.7‐fold, respectively, compared to the 32‐channel adult coil, as well as improved G‐factor maps for accelerated imaging. This study suggests that a size‐tailored approach can provide significant sensitivity gains for accelerated and unaccelerated pediatric brain imaging. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.
Time‐efficient slab‐selective water excitation for 3D MRI
Authors: Lee Gregory R. , Tkach Jean A. , Griswold Mark A. 
Published: June 2011

AbstractSpectral–Spatial (SPSP) radiofrequency pulses are simultaneously selective in both the spectral and spatial domains. To selectively excite water spins and exclude fat, the individual subpulses that make up a SPSP pulse must be short (<1 ms at 4 T). A short subpulse duration limits the sharpness of the spatial slabs that can be excited when using a traditional SPSP pulse design approach. In this manuscript, the authors present an algorithm for designing SPSP pulses with substantially reduced maximum B1 amplitudes and specific absorption rates. The proposed algorithm alternates between iterative design of the radiofrequency waveform for a given gradient shape and minimum‐time variable‐rate selective excitation reshaping of the gradient waveform. This approach is shown to reduce peak B1 amplitudes in iteratively designed SPSP pulses by an order of magnitude. Unlike the use of regularization to control peak B1 or specific absorption rate, the proposed method does not comprise the quality of the excitation profile. To achieve high‐quality profiles, it was necessary to design the radiofrequency pulses for a measured rather than ideal gradient waveform. Slab‐selective water excitation pulses with durations of 4.1 and 9.2 ms (fractional transition widths of 0.14 and 0.073, respectively) are demonstrated at 4 T. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Influence of noise correlation in multiple‐coil statistical models with sum of squares reconstruction
Authors: Aja‐Fernández Santiago , Tristán‐Vega Antonio 
Published: June 2011

AbstractNoise in the composite magnitude signal from multiple‐coil systems is usually assumed to follow a noncentral χ distribution when sum of squares is used to combine images sensed at different coils. However, this is true only if the variance of noise is the same for all coils, and no correlation exists between them. We show how correlations may be obviated from this model if effective values are considered. This implies a reduced effective number of coils and an increased effective variance of noise. In addition, the effective variance of noise becomes signal‐dependent. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
In vivo and ex vivo diffusion tensor imaging of cuprizone‐induced demyelination in the mouse corpus callosum
Authors: Zhang Jiangyang , Jones Melina V. , McMahon Michael T. , Mori Susumu , Calabresi Peter A. 
Published: June 2011

AbstractDiffusion tensor imaging has been widely used in studying rodent models of white matter diseases. In this study, we examined the differences between in vivo and ex vivo fractional anisotropy and diffusivity measurements in the mouse cuprizone model. In the control mouse corpus callosum, ex vivo diffusivities were significantly lower than in vivo measurements, but ex vivo fractional anisotropy values were not significantly different from in vivo fractional anisotropy values. With cuprizone induced demyelination and accompanying pathology in the corpus callosum, changes in in vivo and ex vivo fractional anisotropy and diffusivity measurements were not always in agreement. Our results suggest that ex vivo λ⟂ was a more reliable indicator of white matter demyelination than in vivo λ⟂ and in vivo λ‖ was a more reliable indicator of axonal injury than ex vivo λ‖ in this model. When comparing in vivo and ex vivo diffusion tensor imaging results of axon and myelin pathology in the rodent models, potential changes in tissue microstructures associated with perfusion fixation should be considered. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
X‐PROP: A fast and robust diffusion‐weighted propeller technique
Authors: Li Zhiqiang , Pipe James G. , Lee Chu‐Yu , Debbins Josef P. , Karis John P. , Huo Donglai 
Published: June 2011

AbstractDiffusion‐weighted imaging (DWI) has shown great benefits in clinical MR exams. However, current DWI techniques have shortcomings of sensitivity to distortion or long scan times or combinations of the two. Diffusion‐weighted echo‐planar imaging (EPI) is fast but suffers from severe geometric distortion. Periodically rotated overlapping parallel lines with enhanced reconstruction diffusion‐weighted imaging (PROPELLER DWI) is free of geometric distortion, but the scan time is usually long and imposes high Specific Absorption Rate (SAR) especially at high fields. TurboPROP was proposed to accelerate the scan by combining signal from gradient echoes, but the off‐resonance artifacts from gradient echoes can still degrade the image quality. In this study, a new method called X‐PROP is presented. Similar to TurboPROP, it uses gradient echoes to reduce the scan time. By separating the gradient and spin echoes into individual blades and removing the off‐resonance phase, the off‐resonance artifacts in X‐PROP are minimized. Special reconstruction processes are applied on these blades to correct for the motion artifacts. In vivo results show its advantages over EPI, PROPELLER DWI, and TurboPROP techniques. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Mikrospektroskopie an lebenden Pilzen und Pflanzen
Authors: Vogler Nadine , Walter Angela , Weißflog Ina , Rösch Petra , Kothe Erika , Boland Wilhelm , Dietzek Benjamin , Popp Jürgen 
Published: June 2011

AbstractUm Wachstumsvorgänge in Pilzen oder Umwelteinflüsse auf Pflanzen zu untersuchen, eignen sich Verfahren der Ramanspektroskopie und ‐mikroskopie. Sie machen in lebenden Organismen die Morphochemie sichtbar, durch die sich molekulare Ursachen von Funktions‐ und Strukturänderungen erschließen.
Keine Ernte ohne Bestäuber
Authors: Groß Michael 
Published: June 2011

AbstractDas Sterben ganzer Bienenvölker und der Artenschwund bei Hummeln bedrohen die Landwirtschaft in Europa und Nordamerika. Daran sind vermutlich mehrere Faktoren beteiligt, auch Pflanzenschutzmittel stehen unter Verdacht.
Pilot study evaluating the safety of intradetrusor injections of botulinum toxin type a: Investigation of generalized spread using single‐fiber EMG
Authors: Schnitzler Alexis , Genet François , Durand Marie‐Christine , Roche Nicolas , Bensmail Djamel , Chartier‐Kastler Emmanuel , Denys Pierre 
Published: June 2011

AbstractAimsIntradetrusor botulinum toxin type‐A injections are a novel therapy for treatment of neurogenic overactive bladder resistant to parasympatholytic treatment. In rare cases, however, it may be associated with generalized muscle weakness. Single‐fiber electromyographic (SFEMG) analysis of neuromuscular jitter (NJ) was used to study OnabotulinumtoxinA (BOTOX®) migration to striated muscle.MethodsThis study comprised a prospective, single‐center investigation of 21 spinal cord injured patients receiving intradetrusor OnabotulinumtoxinA. Clinical tolerance was assessed through muscle testing and para‐clinical tolerance by systematic analysis of NJ in muscles distant from the bladder.ResultsTwenty‐one patients (13 males, 8 females) received one intradetrusor injection of 300 U OnabotulinumtoxinA. Mean age was 42.1 ± 14.4 and mean number of injections prior to study inclusion was 2.6 ± 1.7. Clinical and para‐clinical assessments were performed on average 26 days ± 8 days post‐OnabotulinumtoxinA injection. Seven patients had abnormal NJ results on SFEMG, but no patient had evidence of blocking. Four patients complained of tiredness (one with NJ abnormalities).ConclusionsPatients showed good tolerance to intradetrusor OnabotulinumtoxinA injections. Tiredness was not associated with generalized muscle weakness since testing remained unchanged and NMJ was normal in three of four patients. NJ analysis was abnormal in 7 of 21 patients, but this was not considered serious and there was no evidence of muscle fiber block. These results support the safety of bladder injections of OnabotulinumtoxinA and suggest that, although migration of OnabotulinumtoxinA to other muscle groups may impair NJ function in a minority of patients, this does not correlate with symptoms of tiredness or muscle weakness. Neurourol. Urodynam. 30: 1533–1537, 2011. © 2011 Wiley Periodicals, Inc.
Identification of Endothelin‐1 and NR4A2 as CD133‐regulated genes in colon cancer cells
Authors: Puglisi Maria Ausiliatrice , Barba Marta , Corbi Maddalena , Errico Maria Federica , Giorda Ezio , Saulnier Nathalie , Boninsegna Alma , Piscaglia Anna Chiara , Carsetti Rita , Cittadini Achille , Gasbarrini Antonio , Sgambato Alessandro 
Published: June 2011

AbstractSeveral in vitro assays have been proposed to identify cancer stem cells (CSCs), including immunophenotyping, sphere assay and side population (SP) assay. CD133 antigen has been proposed as a CSC marker in colon cancer (CC). However, no functional data are available to date and conflicting results have been reported regarding its role as true CSC marker. Here we set out to identify a molecular signature associated with potential CSC. CD133+ cells isolated from the CaCo‐2 CC cell line were analysed by microarray molecular profiling compared to CD133− counterparts. Various differentially expressed genes were identified and the most relevant transcripts found to be over‐expressed in CD133+ cells were evaluated by quantitative RT‐PCR in the CD133+ fractions isolated from several CC cell lines. In the attempt to find a correlation between putative CSCs, isolated by means of CD133 immunophenotyping and the SP approach, we demonstrated a significant enrichment of CD133+ cells within the SP fraction of CC cells, and comparison of the gene expression profiles revealed that Endothelin‐1 (END‐1) and nuclear receptor subfamily 4, group A, member 2 (NR4A2) transcripts are highly expressed in both CD133+ and SP fractions of CC cells. Moreover, depletion of CD133 by siRNA induced a significant attenuation of END‐1 and NR4A2 expression levels in CaCo‐2 cells, while expression of all three molecules decreased during sodium butyrate‐induced differentiation. In conclusion, we have identified a molecular signature associated with potential CSCs and showed for the first time the existence of a functional relationship between CD133, END‐1 and NR4A2 expression in colon cancer cells. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Proteomic analysis reveals perturbed energy metabolism and elevated oxidative stress in hearts of rats with inborn low aerobic capacity
Authors: Burniston Jatin G. , Kenyani Jenna , Wastling Jonathan M. , Burant Charles F. , Qi Nathan R. , Koch Lauren G. , Britton Steven L. 
Published: June 2011

AbstractSelection on running capacity has created rat phenotypes of high‐capacity runners (HCRs) that have enhanced cardiac function and low‐capacity runners (LCRs) that exhibit risk factors of metabolic syndrome. We analysed hearts of HCRs and LCRs from generation 22 of selection using DIGE and identified proteins from MS database searches. The running capacity of HCRs was six‐fold greater than LCRs. DIGE resolved 957 spots and proteins were unambiguously identified in 369 spots. Protein expression profiling detected 67 statistically significant (p<0.05; false discovery rate <10%, calculated using q‐values) differences between HCRs and LCRs. Hearts of HCR rats exhibited robust increases in the abundance of each enzyme of the β‐oxidation pathway. In contrast, LCR hearts were characterised by the modulation of enzymes associated with ketone body or amino acid metabolism. LCRs also exhibited enhanced expression of antioxidant enzymes such as catalase and greater phosphorylation of α B‐crystallin at serine 59, which is a common point of convergence in cardiac stress signalling. Thus, proteomic analysis revealed selection on low running capacity is associated with perturbations in cardiac energy metabolism and provided the first evidence that the LCR cardiac proteome is exposed to greater oxidative stress.
Poly(ε‐caprolactone)–poly(isobutylene): A crystallizing, hydrogen‐bonded pseudo‐block copolymer
Authors: Ostas Elena , Schröter Klaus , Beiner Mario , Yan Tingzi , Thurn‐Albrecht Thomas , Binder Wolfgang H. 
Published: June 2011

AbstractThe crystallization of block copolymers (BCPs) under homogeneous and heterogeneous nucleation is currently well understood revealing the strong interplay of crystallization in competition to microphase separation. This article reports investigations on synthesis and crystallization processes in weakly interacting supramolecular pseudo‐BCPs, composed of poly(ε‐caprolactone) (PCL) and poly(isobutylene) (PIB) blocks, connected by a specifically interacting hydrogen bond (thymine/2,6‐diaminotriazine). Starting from ring opening polymerization of ε‐caprolactone, the use of “click”‐chemistry enabled the introduction of thymine endgroups onto PCL polymer, thus generating the fully thymine‐substituted pure PCLs (1a, 1b) as judged via NMR and MALDI analysis. Physical mixing of 1a, 1b with a bivalent, bis(2,6‐diaminotriazine)‐containing molecule (2) generated the bivalent polymers BC1 and BC2, whereas mixing of 1a or 1b with the 2,6‐diaminotriazine‐substituted PIB (3) generated the supramolecular pseudo‐BCPs BC3 and BC4. Thermal investigations (DSC, Avrami analysis) revealed only minor changes in the crystallization behavior of BC1–BC4 with Avrami exponents close to three, indicative of a confluence of the growing crystals during the crystallization process. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011