bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hippocampal shape is predictive for the development of dementia in a normal, elderly population
Authors: Achterberg Hakim C. , van der Lijn Fedde , den Heijer Tom , Vernooij Meike W. , Ikram M. Arfan , Niessen Wiro J. , de Bruijne Marleen 
Published: September 2013

AbstractPrevious studies have shown that hippocampal volume is an early marker for dementia. We investigated whether hippocampal shape characteristics extracted from MRI scans are predictive for the development of dementia during follow up in subjects who were nondemented at baseline. Furthermore, we assessed whether hippocampal shape provides additional predictive value independent of hippocampal volume. Five hundred eleven brain MRI scans from elderly nondemented participants of a prospective population‐based imaging study were used. During the 10‐year follow‐up period, 52 of these subjects developed dementia. For training and evaluation independent of age and gender, a subset of 50 cases and 150 matched controls was selected. The hippocampus was segmented using an automated method. From the segmentation, the volume was determined and a statistical shape model was constructed. We trained a classifier to distinguish between subjects who developed dementia and subjects who stayed cognitively healthy. For all subjects the a posteriori probability to develop dementia was estimated using the classifier in a cross‐validation experiment. The area under the ROC curve for volume, shape, and the combination of both were, respectively, 0.724, 0.743, and 0.766. A logistic regression model showed that adding shape to a model using volume corrected for age and gender increased the global model‐fit significantly (P= 0.0063). We conclude that hippocampal shape derived from MRI scans is predictive for dementia before clinical symptoms arise, independent of age and gender. Furthermore, the results suggest that hippocampal shape provides additional predictive value over hippocampal volume and that combining shape and volume leads to better prediction.Hum Brain Mapp 35:2359–2371, 2014. ©2013 Wiley Periodicals, Inc.
White matter microstructure correlates of mathematical giftedness and intelligence quotient
Authors: Navas‐Sánchez Francisco J. , Alemán‐Gómez Yasser , Sánchez‐Gonzalez Javier , Guzmán‐De‐Villoria Juan A. , Franco Carolina , Robles Olalla , Arango Celso , Desco Manuel 
Published: September 2013

AbstractRecent functional neuroimaging studies have shown differences in brain activation between mathematically gifted adolescents and controls. The aim of this study was to investigate the relationship between mathematical giftedness, intelligent quotient (IQ), and the microstructure of white matter tracts in a sample composed of math‐gifted adolescents and aged‐matched controls. Math‐gifted subjects were selected through a national program based on detecting enhanced visuospatial abilities and creative thinking. We used diffusion tensor imaging to assess white matter microstructure in neuroanatomical connectivity. The processing included voxel‐wise and region of interest‐based analyses of the fractional anisotropy (FA), a parameter which is purportedly related to white matter microstructure. In a whole‐sample analysis, IQ showed a significant positive correlation with FA, mainly in the corpus callosum, supporting the idea that efficient information transfer between hemispheres is crucial for higher intellectual capabilities. In addition, math‐gifted adolescents showed increased FA (adjusted for IQ) in white matter tracts connecting frontal lobes with basal ganglia and parietal regions. The enhanced anatomical connectivity observed in the forceps minor and splenium may underlie the greater fluid reasoning, visuospatial working memory, and creative capabilities of these children. Hum Brain Mapp 35:2619–2631, 2014. © 2013 Wiley Periodicals, Inc.
Pin1‐Mediated Prolyl Isomerization of Runx1 Affects PU.1 Expression in Pre‐Monocytes
Authors: ISLAM RABIA , YOON WON‐JOON , WOO KYUNG‐MI , BAEK JEONG‐HWA , RYOO HYUN‐MO 
Published: September 2013

AbstractRegulation of the hematopoietic transcription factor PU.1, a member of the ETS family, plays a critical role in the development of blood cells and in leukemia. The dosage of PU.1 has been shown to cause a shift in myelomonocytic progenitor fate. Pin1 is a unique substrate‐specific enzyme that can isomerize phospho‐Ser/Thr–Pro peptide bonds, accelerating the conformational change in its substrates between a cis and a trans form. Such activity has been demonstrated to be a tightly controlled mechanism regulating a wide variety of protein functions under both normal physiological and pathological conditions. We have previously reported that a conformational change in Runx2 induced by Pin1 is essential for its function in osteogenesis in vitro and in vivo. In this study, we show that the Pin1‐mediated conformational change in Runx1 enhances its acetylation and stabilization and, consequently, enhances its transacting activity. The increased acetylation of Runx1 represses PU.1 transcription in pre‐monocytes. Conversely, the lack of (or the inhibition of) Pin1 increases PU.1 transcription in vitro and in vivo in pre‐monocytes and in the spleen tissue. Pin1 KO mice have an increased CD11b+/F4/80+ cell population and F4/80 protein expression in spleen. From our data, we can conclude that the conformational change in Runx1 induced by Pin1 represses PU.1 transcription in pre‐monocytes and influences the commitment to the monocyte lineage. The dosage of PU.1 is a crucial factor in acute myeloid leukemia (AML), and Pin1 may thus be a useful target for controlling PU.1‐dependent hematopoiesis, as well as leukemogenesis. J. Cell. Physiol. 229: 443–452, 2014. © 2013 Wiley Periodicals, Inc.
Is it possible to implement N‐hydroxyphthalimide homogeneous catalysis for industrial applications? A case study of cumene aerobic oxidation
Authors: Melone Lucio , Prosperini Simona , Ercole Gabriele , Pastori Nadia , Punta Carlo 
Published: September 2013

AbstractBACKGROUNDIn spite of its efficiency and versatility, examples of the use ofN‐hydroxyphthalimide (NHPI) as catalyst for oxidations at industrial scale are scant, mainly due to the lack of methodologies for the recovery and reuse of the catalyst. This paper reports a step by step investigation of the aerobic oxidation of cumene (CU), in order to verify the usability of NHPI catalysis in industrial processes.RESULTSCU is oxidized to the corresponding cumyl hydroperoxide (CHP) at 70°C in the presence of a polar co‐solvent and 1% of NHPI with good conversion (>30%) and almost complete selectivity (>90%), without requiring the use of additional initiators. The catalyst is recovered at the end of the oxidation process by removal of polar co‐solvent, with consequent precipitation of NHPI. The resulting filtered mixture is treated with non‐basic supports, which are capable of adsorbing the residual NHPI by physical interaction. Finally, the adsorbing solids can be regenerated by washing with a polar solvent, allowing the recovery of residual catalyst.CONCLUSIONWe provide evidence for the feasibility of the use of NHPI catalysis for industrial applications by investigating the case study of CU oxidation. The process can be performed under mild conditions without requiring the use of sacrificial initiators. The effect of temperature and composition in the NHPI precipitation step is investigated. The performances of basic and non‐basic adsorbing beds during the recovery of residual NHPI are compared. The results obtained indicate that the recovery and recycling of the unaltered catalyst is possible without affecting, at the same time, the nature of cumyl hydroperoxide. © 2013 Society of Chemical Industry
Repeatability and sensitivity of high resolution blood volume mapping in mouse kidney disease
Authors: Wang Feng , Jiang Rosie T. , Tantawy Mohammed Noor , Borza Dorin B. , Takahashi Keiko , Gore John C. , Harris Raymond C. , Takahashi Takamune , Quarles C. Chad 
Published: September 2013

PurposeTo evaluate the repeatability of MRI‐derived relative blood volume (RBV) measurements in mouse kidneys across subjects and days and to evaluate sensitivity of this approach to renal pathology.Materials and MethodsA 7 Tesla MRI system and an intravascular iron‐oxide contrast agent were used to acquire spin‐echo–based renal RBV maps in 10 healthy mice on 2 consecutive days. Renal RBV maps were also acquired in the Alport and unilateral ureteral obstruction mouse models of renal disease.ResultsThe average renal RBV measured on consecutive days was 19.97 ± 1.50 and 19.86 ± 1.62, yielding a concordance correlation coefficient of 0.94, indicating that this approach is highly repeatable. In the disease models, the RBV values were regionally dissimilar and substantially lower than those found in control mice.ConclusionIn vivo renal iron‐oxide–based RBV mapping in mice complements the physiological information obtained from conventional assays of kidney function and could shed new insights into the pathological mechanisms of kidney disease. J. Magn. Reson. Imaging 2014;39:866–871. © 2013 Wiley Periodicals, Inc.
Improved field post‐processing for a Stern–Gerlach magnetic deflection magnet
Authors: De Gersem H. , Masschaele B. , Roggen T. , Janssens E. , Tung N.T. 
Published: September 2013

SUMMARYA Stern–Gerlach magnet applies a field gradient in order to deflect particles such that their magnetic moment can be determined. The design of such magnets is based on finite‐element (FE) simulations of the magnetic field and its gradient. However, inaccuracies arise when these quantities are calculated from an FE solution for the magnetic vector potential by numerical differentiation. For first‐order FE shape functions, the discretisation error for the field gradient may even fail to converge. An improved post‐processing approach marks a region in the magnet aperture where the field is post‐processed by matching a local analytical solution with the obtained FE solution. The local solution allows to derive values for the magnetic field and its gradient without reducing the convergence order of the discretisation error. The method is validated against the analytic solution for a two‐wire configuration and is applied for the design of a Rabi‐type Stern–Gerlach magnet. Copyright © 2013 John Wiley & Sons, Ltd.
Schneiden mit dem Laser MicroJet
Authors: Richmann Annika 
Published: September 2013

AbstractDas Laser MicroJet‐Schneiden (LMJ) wird bereits in vielen industriellen Anwendungen zum Schneiden von Diamant, Halbleiter und Metallen eingesetzt. Vorteile des LMJs gegenüber anderen Technologien sind hohe Kantenqualität, keine Wärmeeinflusszone, große Abtragraten und große Aspektverhältnisse der Schnittfugen. Kürzlich ließ sich durch Prozessweiterentwicklung die Rauheit der Kanten, abhängig vom geschnittenen Material, auf Ra = 0,3 – 0,5 μm reduzieren.
Reverse Iodine Transfer Polymerization (RITP) of 1,1,2,2‐Tetrahydroperfluorodecyl Acrylate in Supercritical Carbon Dioxide
Authors: Bouilhac Cécile , Chirat Mathieu , Joly‐Duhamel Christine , Lacroix‐Desmazes Patrick 
Published: September 2013

Reverse iodine transfer polymerization (RITP) of 1,1,2,2‐tetrahydroperfluorodecyl acrylate (FDA) is successfully performed in supercritical carbon dioxide (scCO2) at 70 °C under a CO2 pressure of 300 bar. PolyFDA (PFDA) of increasing molecular weights (from 10 000 to 100 000 g mol−1) is synthesized with good agreement between theoretical, 1H NMR spectroscopy and and size exclusion chromatography/refractive index/right‐angle laser‐light scattering/differential viscometer (SEC/RI/RALLS/DV)‐estimated molecular weights (). Furthermore, the increase of goes with a decrease of the dispersity of the polymers (Đ from 2.06 to 1.33), which is consistent with a controlled radical polymerization (CRP). Lastly, the structure of final PFDA and therefore the RITP process are confirmed by matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) analyses.
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Effect of Operating Conditions on Dynamic Crystallization of Ethylene/1‐Octene Copolymers
Authors: Chokputtanawuttilerd Nuttawat , Anantawaraskul Siripon , Alghyamah Abdulaziz A. , Soares João B. P. 
Published: September 2013

Dynamic crystallization (DC) is a new characterization technique for measuring the chemical composition distribution (CCD) of semicrystalline copolymers. This technique fractionates polymers based on chain crystallizabilities under a constant cooling rate; a solvent is also fed through the column at a constant flow rate during the crystallization to enhance the physical separation of the polymer fractions. In this work, a DC model for ethylene/1‐olefin copolymers on the basis of population balance, crystallization kinetics, and axial dispersion is proposed. This model is found to describe the experimental DC profiles of an ethylene/1‐octene copolymer at various operation conditions very well.
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Molecular Recognition: Influence of Para‐Versus‐Meta‐Substituted Phenyl Moieties on the Swelling Degree of Macroscopic Polymeric Gels in Aqueous Cyclodextrin Solutions
Authors: van Sloun Claudia , Peters Oliver , Tabatabai Monir , Ritter Helmut 
Published: September 2013

Free radical terpolymerization of (N,N)‐dimethylacrylamide, ethylene‐glycol‐dimethacrylate and N‐(p‐ or m‐ethyl‐phenyl)acrylamide leads to para‐ and meta‐ethyl‐phenyl‐modified hydrophilic polymer networks. Polymeric networks of different molar ratios are prepared in special molds to give water swellable disc‐ shaped samples. The swelling behavior in water and aqueous cyclodextrin (CD) solution of the obtained samples is described while a distinctive differentiation between the para‐ and meta‐ethyl‐phenyl containing networks in CD solution can be found.
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A Facile Route to Viologen Functional Macromolecules through Azide–Alkyne [3+2] Cycloaddition
Authors: Janeček Emma‐Rose , Rauwald Urs , del Barrio Jesús , Cziferszky Monika , Scherman Oren A. 
Published: September 2013

Viologen end and side‐chain functional macromolecules are synthesized through a high‐yielding, copper‐mediated azide–alkyne [3+2] cycloaddition reaction. Specifically, poly(ethylene glycol) (PEG) and the C‐terminus of a model oligopeptide are quantitatively end‐coupled to a viologen moiety as confirmed by 1H NMR, gel permeation chromatography (GPC), and mass spectrometry (MS). Side‐chain functionalization of a styrene backbone is also readily achieved forming a polyelectrolyte species and demonstrating the applicability of this method across a range of macromolecular species. It is found that viologen itself slows the reaction and that careful choice of counter ions, the specific chelating ligand for the copper‐mediated reaction, solvent, as well as the amount of copper also play major roles in the time to completion of the reaction and hence the yield. Macromolecules formed through this route bind effectively with supramolecular host molecule cucurbit[8]uril allowing for controlled solution‐phase self‐assembly, for example of a supramolecular star polymer.
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Renewable Non‐Isocyanate Based Thermoplastic Polyurethanes via Polycondensation of Dimethyl Carbamate Monomers with Diols
Authors: Unverferth Maike , Kreye Oliver , Prohammer Alexander , Meier Michael A. R. 
Published: September 2013

1,5,7‐Triazabicyclo[4.4.0]dec‐5‐ene (TBD)‐catalyzed polycondensation reactions of fatty acid derived dimethyl dicarbamates and diols are introduced as a versatile, non‐isocyanate route to renewable polyurethanes. The key step for the synthesis of dimethyl carbamate monomers from plant‐oil‐derived dicarboxylic acids is based on a sustainable base‐catalyzed Lossen rearrangement. The formed polyurethanes with molecular weights up to 25 kDa are characterized by SEC, DSC, and NMR analysis.
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Electrochromic Poly(acetylene)s with Switchable Visible/Near‐IR Absorption Characteristics
Authors: Pauly Anja C. , Varnado C. Daniel , Bielawski Christopher W. , Theato Patrick 
Published: September 2013

Ferrocene is incorporated into a poly(acetylene) derivative via the postpolymerization amidation of a polymer precursor bearing pentafluorophenyl ester‐leaving groups with aminoferrocene. While the neutral polymer exhibits a strong absorbance at 553 nm due to its conjugated backbone, oxidation of the ferrocene moieties with silver tetrafluoroborate causes the material to absorb in the near‐IR (λmax ≈1215 nm). Subsequent reduction of the oxidized polymer with decamethylferrocene restores the initial absorbance profile, demonstrating that the material features switchable visible/near‐IR absorption characteristics.
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Vig r 6, the cytokinin‐specific binding protein from mung bean (Vigna radiata) sprouts, cross‐reacts with Bet v 1‐related allergens and binds IgE from birch pollen allergic patients’ sera
Authors: Guhsl Eva Elisabeth , Hofstetter Gerlinde , Hemmer Wolfgang , Ebner Christof , Vieths Stefan , Vogel Lothar , Breiteneder Heimo , Radauer Christian 
Published: September 2013

ScopeBirch pollen associated allergy to mung bean sprouts is caused by cross‐reactivity between the birch pollen allergen Bet v 1 and the mung bean allergen Vig r 1. We aimed to determine the allergenicity of the cytokinin‐specific binding protein from mung bean (Vig r 6), another allergen related to Bet v 1 with only 31% sequence identity.Methods and resultsBet v 1, Gly m 4, Vig r 1, and Vig r 6 were produced in Escherichia coli. In an ELISA, 73 and 32% of Bet v 1‐sensitized birch‐allergic patients’ sera (n = 60) showed IgE binding to Vig r 1 and Vig r 6, respectively. Of 19 patients who reported allergic reactions or had positive prick‐to‐prick tests to mung bean sprouts, 79% showed IgE binding to Vig r 1 and 63% showed IgE binding to Vig r 6. Bet v 1 completely inhibited IgE binding to both mung bean allergens. Vig r 6 showed partial cross‐reactivity with Vig r 1 and activated basophils sensitized with mung bean allergic patients’ sera.ConclusionWe demonstrated IgE cross‐reactivity despite low sequence identity between Vig r 6 and other Bet v 1‐related allergens. Thus, IgE binding to Vig r 6 may contribute to birch pollinosis‐associated mung bean sprout allergy.
Nondigestible oligosaccharides exert nonprebiotic effects on intestinal epithelial cells enhancing the immune response via activation of TLR4‐NFκB
Authors: Ortega‐González Mercedes , Ocón Borja , Romero‐Calvo Isabel , Anzola Andrea , Guadix Emilia , Zarzuelo Antonio , Suárez Maria D. , Sánchez de Medina Fermin , Martínez‐Augustin Olga 
Published: September 2013

ScopePrebiotic effects of non absorbable glucids depend mainly on digestion by the colonic microbiota. Our aim was to assess nonprebiotic, direct effects of 4 prebiotics, namely fructooligosaccharides, inulin, galactooligosaccharides, and goat's milk oligosaccharides on intestinal epithelial cells.Methods and resultsPrebiotics were tested in intestinal epithelial cell 18 (IEC18), HT29, and Caco‐2 cells. Cytokine secretion was measured by ELISA and modulated with pharmacological probes and gene silencing. Prebiotics induced the production of growth‐related oncogene, (GROα), monocyte chemoattractant protein 1 (MCP‐1), and macrophage inflammatory protein 2 (MIP2) in IEC18 cells, with an efficacy that was 50–80% that of LPS. Prebiotics did not change RANTES expression, which was robustly induced by LPS in IEC18 cells. Cytokine secretion was suppressed by Bay11‐7082, an inhibitor of IκB‐α phosphorylation. The response was markedly decreased by Myd88 or TLR4 gene knockdown. Prebiotics also elicited cytokine production in HT29 but not in Caco‐2 cells, consistent with reduced and vestigial expression of TLR4 in these cell lines, respectively. Prebiotic‐induced MCP‐1 secretion was reduced also in colonic explants from TLR4 KO mice compared with the controls.ConclusionsWe conclude that prebiotics are TLR4 ligands in intestinal epithelial cells and that this may be a relevant mechanism for their in vivo effects.
Nonrigid autofocus motion correction for coronary MR angiography with a 3D cones trajectory
Authors: Ingle R. Reeve , Wu Holden H. , Addy Nii Okai , Cheng Joseph Y. , Yang Phillip C. , Hu Bob S. , Nishimura Dwight G. 
Published: September 2013

PurposeTo implement a nonrigid autofocus motion correction technique to improve respiratory motion correction of free‐breathing whole‐heart coronary magnetic resonance angiography acquisitions using an image‐navigated 3D cones sequence.Methods2D image navigators acquired every heartbeat are used to measure superior‐inferior, anterior‐posterior, and right‐left translation of the heart during a free‐breathing coronary magnetic resonance angiography scan using a 3D cones readout trajectory. Various tidal respiratory motion patterns are modeled by independently scaling the three measured displacement trajectories. These scaled motion trajectories are used for 3D translational compensation of the acquired data, and a bank of motion‐compensated images is reconstructed. From this bank, a gradient entropy focusing metric is used to generate a nonrigid motion‐corrected image on a pixel‐by‐pixel basis. The performance of the autofocus motion correction technique is compared with rigid‐body translational correction and no correction in phantom, volunteer, and patient studies.ResultsNonrigid autofocus motion correction yields improved image quality compared to rigid‐body‐corrected images and uncorrected images. Quantitative vessel sharpness measurements indicate superiority of the proposed technique in 14 out of 15 coronary segments from three patient and two volunteer studies.ConclusionThe proposed technique corrects nonrigid motion artifacts in free‐breathing 3D cones acquisitions, improving image quality compared to rigid‐body motion correction. Magn Reson Med 72:347–361, 2014. © 2013 Wiley Periodicals, Inc.
Geometry motivated alternative view on local protein backbone structures
Authors: Zacharias Jan , Knapp Ernst Walter 
Published: September 2013

AbstractWe present an alternative to the classical Ramachandran plot (R‐plot) to display local protein backbone structure. Instead of the (φ, ψ)‐backbone angles relating to the chemical architecture of polypeptides generic helical parameters are used. These are the rotation or twist angle ϑ and the helical rise parameter d. Plots with these parameters provide a different view on the nature of local protein backbone structures. It allows to display the local structures in polar (d, ϑ)‐coordinates, which is not possible for an R‐plot, where structural regimes connected by periodicity appear disconnected. But there are other advantages, like a clear discrimination of the handedness of a local structure, a larger spread of the different local structure domains—the latter can yield a better separation of different local secondary structure motives—and many more. Compared to the R‐plot we are not aware of any major disadvantage to classify local polypeptide structures with the (d, ϑ)‐plot, except that it requires some elementary computations. To facilitate usage of the new (d, ϑ)‐plot for protein structures we provide a web application (http://agknapp.chemie.fu‐berlin.de/secsass), which shows the (d, ϑ)‐plot side‐by‐side with the R‐plot.