bluuebunny/crossref_metadata_2025_split huggingface dataset:
A more clear insight of the lysozyme crystal composition
Authors: Müller C. , Ulrich J. 
Published: June 2011

AbstractCrystallization can be used as a purification method for proteins. Lysozyme was chosen as a model substance. Changing crystallization conditions will lead as shown to different lysozyme crystal morphologies with different properties. Beside others, lysozyme crystals can show a Tetragonal, High Temperature and Low Temperature Orthorhombic crystal morphology. Experiments such as conductivity measurements, pH tests, chloride detection tests, experiments using methylene blue as a dye and dissolution experiments were carried out to investigate the composition of the lysozyme crystals. It is proven that lysozyme crystals are made up of the initial buffer solution components: lysozyme (the protein), water which is part of the crystal lattice, salt ions which are attached to the protein molecule and voids filled with the buffer solution containing the crystallization agent (e.g. salt). Interesting dissolution behaviours of the lysozyme crystals were observed which are not described so far elsewhere (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of ferric ions on the morphology and size of magnetite nanocrystals synthesized by ultrasonic irradiation
Authors: Cheng J. P. , Ma R. , Chen X. , Shi D. , Liu F. , Zhang X. B. 
Published: June 2011

AbstractTwo‐dimensional plate‐like Fe3O4 nanocrystals and nanoparticles could be synthesized by a simple one‐step sonochemical method through ultrasonic irradiation in reverse co‐precipitation solution at low temperature. This technique provided a facile and rapid way to prepare Fe3O4nanocrystals with different morphology and size. Magnetite nanoplates were synthesized with only ferrous salt adding into alkali solution, and adding ferric ions with low molar ratio in the metal salts solution would lead to the formation of very small magnetite nanoparticles (∼10 nm). The size of as‐prepared magnetite nanoparticles increased with increasing reaction temperature and showed narrow size distribution, the standard deviation less than 2 nm. This investigation indicated that ferric ions had significant influence on the morphology of Fe3O4 nanocrystals. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A new nonlinear optical crystal: Bi2O2(OH)(NO3)
Authors: Wang Cuiping , Liu Qian , Li Zhihua 
Published: June 2011

AbstractThe nonlinear optical (NLO) properties of Bi2O2(OH)(NO3) crystals have been reported for the first time. Bi2O2(OH)(NO3) crystals with dimensions of 1.3×1.2×0.1 mm3 have been grown by hydrothermal method, and the crystals characterized by X‐ray powder diffraction (XRD), SEM and IR. The measured second harmonic generation (SHG) effect of Bi2O2(OH)(NO3) was about 7 times that of KDP. The mechanism responsible for the large SHG of Bi2O2(OH)(NO3) was explained according to its structure. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Expression patterns of Ephs and ephrins throughout retinotectal development in Xenopus laevis
Authors: Higenell Valerie , Han Sang Myung , Feldheim David A. , Scalia Frank , Ruthazer Edward S. 
Published: June 2011

AbstractThe Eph family of receptor tyrosine kinases and their ligands the ephrins play an essential role in the targeting of retinal ganglion cell axons to topographically correct locations in the optic tectum during visual system development. The African claw‐toed frog Xenopus laevis is a popular animal model for the study of retinotectal development because of its amenability to live imaging and electrophysiology. Its visual system undergoes protracted growth continuing beyond metamorphosis, yet little is known about ephrin and Eph expression patterns beyond stage 39 when retinal axons first arrive in the tectum. We used alkaline phosphatase fusion proteins of EphA3, ephrin‐A5, EphB2, and ephrin‐B1 as affinity probes to reveal the expression patterns of ephrin‐As, EphAs, ephrin‐Bs, and EphBs, respectively. Analysis of brains from stage 40 to adult frog revealed that ephrins and Eph receptors are expressed throughout development. As observed in other species, staining for ephrin‐As displayed a high caudal to low rostral expression pattern across the tectum, roughly complementary to the expression of EphAs. In contrast with the prevailing model, EphBs were found to be expressed in the tectum in a high dorsal to low ventral gradient in young animals. In animals with induced binocular tectal innervation, ocular dominance bands of alternating input from the two eyes formed in the tectum; however, ephrin‐A and EphA expression patterns were unmodulated and similar to those in normal frogs, confirming that the segregation of axons into eye‐specific stripes is not the consequence of a respecification of molecular guidance cues in the tectum. © 2011 Wiley Periodicals, Inc. Develop Neurobiol 72: 547–563, 2012
Childhood emotional abuse and eating symptoms in bulimic disorders: An examination of possible mediating variables
Authors: Groleau Patricia , Steiger Howard , Bruce Kenneth , Israel Mimi , Sycz Lindsay , Ouellette Anne‐Sophie , Badawi Ghislaine 
Published: June 2011

AbstractObjective:We sought to estimate prevalences of childhood emotional abuse (CEA) in bulimic and normal‐eater control groups, and to replicate previous findings linking CEA to severity of eating symptoms in BN. We also examined potential mediators of the link between CEA and disordered eating.Method:Women diagnosed with a bulimic disorder (n = 176) and normal‐eater women (n = 139) were assessed for childhood traumata, eating‐disorder (ED) symptoms and psychopathological characteristics (ineffectiveness, perfectionism, depression, and affective instability) thought to be potential mediators of interest.Results:CEA was more prevalent in the bulimic than in the nonbulimic group, and predicted severity of some eating‐symptom indices. Ineffectiveness and affective instability both mediated relationships between CEA and selected ED symptoms.Discussion:We found CEA to predict eating pathology through mediating effects of ineffectiveness and affective instability. CEA might influence severity of ED symptoms by impacting an individual's self‐esteem and capacity for affect regulation. © 2011 by Wiley Periodicals, Inc. (Int J Eat Disord 2012)
A Study of Factors Affecting Enantioselectivity in the Oxidation of Aryl Benzyl Sulfides in the Presence of Chiral Titanium Catalysts
Authors: Capozzi Maria Annunziata M. , Centrone Caterina , Fracchiolla Giuseppe , Naso Francesco , Cardellicchio Cosimo 
Published: June 2011

AbstractA series of experiments was performed to test a theoretical model that we have recently proposed to explain the highly enantioselective oxidation of aryl benzyl sulfides with tert‐butyl hydroperoxide in the presence of a complex between titanium and (S,S)‐ or (R,R)‐hydrobenzoin. The studied variations involved the sulfides, the ligands, and the order of addition of reactants. The reaction path predicted by our model was confirmed in every experiment. In particular, aryl benzyl sulfides behaved as the ideal substrate for this type of asymmetric oxidation, which yields synthetically useful, enantiopure aryl benzyl sulfoxides in a straightforward manner.
Thermoregulated Copper‐Free Sonogashira Coupling in Water
Authors: Liu Ning , Liu Chun , Xu Qiang , Jin Zilin 
Published: June 2011

AbstractThe Sonogashira cross‐coupling reaction between aryl halides and terminal alkynes was carried out smoothly in water over a thermoregulated ligand–palladium catalyst under copper‐free conditions, resulting in good to excellent yields. The Sonogashira reaction was sensitive to the electronic nature of the substituents on the aryl halides. Aryl halides with an electron‐withdrawing group showed higher reactivity than those with an electron‐donating group. Particularly, this protocol could be applied to the synthesis of liquid crystals involving trans‐cyclohexyltolans. The products could be separated from the reaction system easily by decanting, and the catalyst was recovered in water and used directly for the next run.
Exploration of the Scope of Pt‐Catalyzed C–F Activation
Authors: Keyes Lauren , Sun Alex D. , Love Jennifer A. 
Published: June 2011

AbstractWe recently reported methods for the catalytic methylation and methoxylation of polyfluoroaryl imines utilizing [Pt2Me4(SMe2)2] as a precatalyst. These methodologies provide a novel route to partially functionalized aryl fluorides, which have potential utility as building blocks for the synthesis of pharmaceuticals and materials. We report herein efforts to expand the scope of these processes, particularly the choice of directing group. Comparisons to the previously reported scope of PtII‐catalyzed methylation and methoxylation are described.
Automated detection and characterization of SPIO‐labeled cells and capsules using magnetic field perturbations
Authors: Mills Parker H. , Hitchens T. Kevin , Foley Lesley M. , Link Thomas , Ye Qing , Weiss Clifford R. , Thompson Joe D. , Gilson Wesley D. , Arepally Aravind , Melick John A. , Kochanek Patrick M. , Ho Chien , Bulte Jeff W. M. , Ahrens Eric T. 
Published: June 2011

AbstractUnderstanding how individual cells behave inside living systems will help enable new diagnostic tools and cellular therapies. Superparamagnetic iron oxide particles can be used to label cells and theranostic capsules for noninvasive tracking using MRI. Contrast changes from superparamagnetic iron oxide are often subtle relative to intrinsic sources of contrast, presenting a detection challenge. Here, we describe a versatile postprocessing method, called Phase map cross‐correlation Detection and Quantification (PDQ), that automatically identifies localized deposits of superparamagnetic iron oxide, estimating their volume magnetic susceptibility and magnetic moment. To demonstrate applicability, PDQ was used to detect and characterize superparamagnetic iron oxide‐labeled magnetocapsules implanted in porcine liver and suspended in agarose gel. PDQ was also applied to mouse brains infiltrated by MPIO‐labeled macrophages following traumatic brain injury; longitudinal, in vivo studies tracked individual MPIO clusters over 3 days, and tracked clusters were corroborated in ex vivo brain scans. Additionally, we applied PDQ to rat hearts infiltrated by MPIO‐labeled macrophages in a transplant model of organ rejection. PDQ magnetic measurements were signal‐to‐noise ratio invariant for images with signal‐to‐noise ratio > 11. PDQ can be used with conventional gradient‐echo pulse sequences, requiring no extra scan time. The method is useful for visualizing biodistribution of cells and theranostic magnetocapsules and for measuring their relative iron content. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
The influence of radial undersampling schemes on compressed sensing reconstruction in breast MRI
Authors: Chan Rachel W. , Ramsay Elizabeth A. , Cheung Edward Y. , Plewes Donald B. 
Published: June 2011

AbstractFast imaging applications in magnetic resonance imaging (MRI) frequently involve undersampling of k‐space data to achieve the desired temporal resolution. However, high temporal resolution images generated from undersampled data suffer from aliasing artifacts. In radial k‐space sampling, this manifests as undesirable streaks that obscure image detail. Compressed sensing reconstruction has been shown to reduce such streak artifacts, based on the assumption of image sparsity. Here, compressed sensing is implemented with three different radial sampling schemes (golden‐angle, bit‐reversed, and random sampling), which are compared over a range of spatiotemporal resolutions. The sampling methods are implemented in static scenarios where different undersampling patterns could be compared. Results from point spread function studies, simulations, phantom and in vivo experiments show that the choice of radial sampling pattern influences the quality of the final image reconstructed by the compressed sensing algorithm. While evenly undersampled radial trajectories are best for specific temporal resolutions, golden‐angle radial sampling results in the least overall error when various temporal resolutions are considered. Reduced temporal fluctuations from aliasing artifacts in golden‐angle sampling translates to improved compressed sensing reconstructions overall. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Quantification techniques to minimize the effects of native T1 variation and B1 inhomogeneity in dynamic contrast‐enhanced MRI of the breast at 3 T
Authors: Azlan Che A. , Ahearn Trevor S. , Di Giovanni Pierluigi , Semple Scott I. K. , Gilbert Fiona J. , Redpath Thomas W. 
Published: June 2011

AbstractThe variation of the native T1 (T10) of different tissues and B1 transmission‐field inhomogeneity at 3 T are major contributors of errors in the quantification of breast dynamic contrast‐enhanced MRI. To address these issues, we have introduced new enhancement indices derived from saturation‐recovery snapshot‐FLASH (SRSF) images. The stability of the new indices, i.e., the SRSF enhancement factor (EFSRSF) and its simplified version (EF′SRSF) with respect to differences in T10 and B1 inhomogeneity was compared against a typical index used in breast dynamic contrast‐enhanced MRI, i.e., the enhancement ratio (ER), by using computer simulations. Imaging experiments with Gd‐DTPA‐doped gel phantoms and a female volunteer were also performed. A lower error was observed in the new indices compared to enhancement ratio in the presence of typical T10 variation and B1 inhomogeneity. At changes of relaxation rate (ΔR1) of 8 s−1, the differences between a T10 of 1266 and 566 ms are <1, 12, and 58%, respectively, for EFSRSF, EF′SRSF, and ER, whereas differences of 20, 8, and 51%, respectively, result from a 50% B1 field reduction at the same ΔR1. These quantification techniques may be a solution to minimize the effect of T10 variation and B1 inhomogeneity on dynamic contrast‐enhanced MRI of the breast at 3 T. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Reverse polarized inductive coupling to transmit and receive radiofrequency coil arrays
Authors: Celik Haydar , Atalar Ergin 
Published: June 2011

AbstractIn this study, the reverse polarization method is implemented using transmit and receive arrays to improve the visibility of the interventional devices. Linearly polarized signal sources—inductively and receptively coupled radiofrequency coils—are used in the experimental setups to demonstrate the ability of the method to separate these sources from a forward polarized anatomy signal. Two different applications of the reverse polarization method are presented here: (a) catheter tracking and (b) fiducial marker visualization, in both of which transmit and receive arrays are used. The performance of the reverse polarization method was further tested with phantom and volunteer studies, and the results proved the feasibility of this method with transmit and receive arrays. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
From the genome sequence to the protein inventory of Bacillus subtilis
Authors: Becher Dörte , Büttner Knut , Moche Martin , Heßling Bernd , Hecker Michael 
Published: June 2011

AbstractOwing to the low number of proteins necessary to render a bacterial cell viable, bacteria are extremely attractive model systems to understand how the genome sequence is translated into actual life processes. One of the most intensively investigated model organisms is Bacillus subtilis. It has attracted world‐wide research interest, addressing cell differentiation and adaptation on a molecular scale as well as biotechnological production processes. Meanwhile, we are looking back on more than 25 years of B. subtilis proteomics. A wide range of methods have been developed during this period for the large‐scale qualitative and quantitative proteome analysis. Currently, it is possible to identify and quantify more than 50% of the predicted proteome in different cellular subfractions. In this review, we summarize the development of B. subtilis proteomics during the past 25 years.
The superhydrophobicity of polymer surfaces: Recent developments
Authors: Shirtcliffe Neil J. , McHale Glen , I. Newton Michael 
Published: June 2011

AbstractSuperhydrophobicity is the extreme water repellence of highly textured surfaces. The field of superhydrophobicity research has reached a stage where huge numbers of candidate treatments have been proposed and jumps have been made in theoretically describing them. There now seems to be a move to more practical concerns and to considering the demands of individual applications instead of more general cases. With these developments, polymeric surfaces with their huge variety of properties have come to the fore and are fast becoming the material of choice for designing, developing, and producing superhydrophobic surfaces. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1203–1217, 2011
Quantum confinement effect on 2DEG in InGaN/InN HEMT with an interfacial layer
Authors: Muhtadi Sakib M. , Sajjad Hossain S. M. , Bhuiyan Ashraful G. , Sasamoto K. , Hashimoto A. , Yamamoto A. 
Published: June 2011

AbstractQuantum confinement effect on 2DEG density and distribution on the dependence of an interfacial layer has been investigated in InGaN/InN HEMT using self‐consistent solution of one dimensional Schrödinger‐Poisson equation. It is shown that the addition of an i‐InGaN interfacial layer leads to an increase in 2DEG density. The role of quantum confinement effect in the 2DEG distribution with an inserted i‐InGaN interfacial layer is revealed. In the classical model, the insertion of an interfacial layer has a negligible effect on 2DEG distribution. While taking the quantum effect along with polarization effect into account, it is observed that i‐InGaN interfacial layer has substantial influence on the 2DEG distribution in InGaN/InN HEMT; with electron spillover into the barrier is sharply reduced. The maximum 2DEG density after insertion of an i‐InGaN interfacial layer has been found to be 1 × 1014 cm‐2 which is higher than the conventional GaN‐based HEMT (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Assessment of reproductive biomarkers in three‐spined stickleback (Gasterosteus aculeatus) from sewage effluent recipients
Authors: Björkblom Carina , Mustamäki Noora , Olsson Per‐Erik , Katsiadaki Ioanna , Wiklund Tom 
Published: June 2011

AbstractThe aim of this study was to examine the occurrence of endocrine disruption close to sewage treatment plant effluent discharges along the Finnish Baltic Sea coast using a set of reproductive biomarkers present in adult three‐spined stickleback (Gasterosteus aculeatus). Possible variation and sensitivity of the biomarkers during an entire reproductive period were also examined. The analysis of vitellogenin (VTG) for estrogenic activity and spiggin for androgenic activity, together with histopathological analysis indicated that sticklebacks were exposed to estrogenic loads sufficient to cause inappropriate production of VTG and to disrupt normal testicular structure in adult male sticklebacks. No androgenic disruption was observed. The results emphasize the need of a combination of several reproductive biomarkers in fish and repeated sampling for the detection of potential endocrine modulating substances under field condition. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013.
Catalase activity and innate immune response of Caenorhabditis elegans against the heavy metal toxin lead
Authors: Vigneshkumar Balasubramanian , Pandian Shunmugiah Karutha , Balamurugan Krishnaswamy 
Published: June 2011

AbstractThe heavy metal lead‐induced oxidative stress on Caenorhabditis elegans was examined at the level of catalase activity and on innate immunity. Stress‐induced C. elegans was exposed to Pseudomonas aeruginosaPA14::GFP for monitoring the impact at the physiological level. Role of catalase on the innate‐immune responses of C. elegans was examined. PA14::GFP did not colonize lead pretreated C. elegans intestinal cells significantly compared to untreated controls, indicating stress‐mediated upregulation of host‐immunity. Semiquantitative PCR analyses of lead‐exposed and PA14‐infected C. elegans mRNA showed significant upregulation of candidate antimicrobial enzyme gene lys‐7 after 24 h of exposures. Upregulation of metallothionein(mtl‐1) when compared to mtl‐2 in response to the lead suggesting active detoxification of metal by mtl‐1. Exogenously provided Catalase (0.4–3.2 U) induced significant upregulation of lys‐7 compared to controls. lys‐7 upregulation during lead exposure was reconfirmed by real‐time PCR. Confocal microscopy and fluorescence spectrophotometer analyses indicated that the lead pretreated C. elegans was significantly less colonized by PA14::GFP when compared to controls. Relative expression of ctl‐1 and ctl‐2 mRNA was measured using real time PCR and found to be regulated during lead exposures. Over all, the upregulation of antimicrobial gene expression appears to be correlated with the level of catalase during stress emphasizing their key roles in defensive mechanism(s). These results provide a link between the stress and related immune responses which can be explored in higher systems. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013.
Molecular mechanism of inflammatory response in mouse liver caused by exposure to CeCl3
Authors: Li Na , Cheng Jie , Cheng Zhe , Hu Renping , Cai Jingwei , Gao Guodong , Cui Yaling , Wang Ling , Hong Fashui 
Published: June 2011

AbstractTo investigate the molecular mechanism of inflammatory response in the mouse liver caused by exposure to CeCl3, we measured the liver indices, and cerium content, evaluated the liver histopathological section, detected serum biochemical parameters of liver function, and the immunoglobulin M (IgM) content, analyzed the liver mRNA and protein expression levels of Toll‐like receptor 2, 4 (TLR2, TLR4), and inflammatory cytokines in liver using real‐time quantitative reverse transcriptase polymerase chain reaction and enzyme‐linked immunosorbent assay. The results showed that exposure to CeCl3 decreased body weight and caused cerium accumulation in the mouse liver and histopathological changes of liver (such as inflammatory cell infiltration). Furthermore, biochemical assays suggested that CeCl3 could promote the activities of alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, lactate dehydrogenase, pseudocholinesterase, and leucine aminopeptidase, decrease serum IgM, upregulate the levels of TLR2, TLR4, nuclear factor‐κB (NF‐κB), NF‐κBp52, NF‐κBp65, NF‐κB‐inducing kinase (NIK), IκB kinase α (IKK‐α), IκB kinase β (IKK‐β), and tumor necrosis factor‐α (TNF‐α) expression, and suppress NF‐κB‐inhibiting factor (IκB) and interleukin‐2 (IL‐2) expression in liver. Taken together, the inflammation of mice liver caused by exposure to CeCl3 might be closely associated with the alteration of inflammatory cytokine expressions in the mouse liver, the signal‐transducing events happening in CeCl3‐induced macrophages of liver sequentially might occur via activation of TLRs→TNF‐α→NIK→IκB kinase (including IKK1, IKK2)→NF‐κB (including NF‐κBP52, NF‐κBP65)→ inflammation. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013.