bluuebunny/crossref_metadata_2025_split huggingface dataset:
Accelerated T2 mapping combining parallel MRI and model‐based reconstruction: GRAPPATINI
Authors: Hilbert Tom , Sumpf Tilman J. , Weiland Elisabeth , Frahm Jens , Thiran Jean‐Philippe , Meuli Reto , Kober Tobias , Krueger Gunnar 
Published: February 2018

BackgroundQuantitative T2 measurements are sensitive to intra‐ and extracellular water accumulation and myelin loss. Therefore, quantitative T2 promises to be a good biomarker of disease. However, T2 measurements require long acquisition times.PurposeTo accelerate T2 quantification and subsequent generation of synthetic T2‐weighted (T2‐w) image contrast for clinical research and routine. To that end, a recently developed model‐based approach for rapid T2 and M0 quantification (MARTINI) based on undersampling k‐space, was extended by parallel imaging (GRAPPA) to enable high‐resolution T2 mapping with access to T2‐w images in less than 2 minutes acquisition time for the entire brain.Study TypeProspective cross‐sectional study.Subjects/PhantomFourteen healthy subjects and a multipurpose phantom.Field Strength/SequenceCarr–Purcell–Meiboom‐Gill sequence at a 3T scanner.AssessmentThe accuracy and reproducibility of the accelerated T2 quantification was assessed. Validations comprised MRI studies on a phantom as well as the brain, knee, prostate, and liver from healthy volunteers. Synthetic T2‐w images were generated from computed T2 and M0 maps and compared to conventional fast spin‐echo (SE) images.Statistical TestsRoot mean square distance (RMSD) to the reference method and region of interest analysis.ResultsThe combination of MARTINI and GRAPPA (GRAPPATINI) lead to a 10‐fold accelerated T2 mapping protocol with 1:44 minutes acquisition time and full brain coverage. The RMSD of GRAPPATINI increases less (4.3%) than a 10‐fold MARTINI reconstruction (37.6%) in comparison to the reference. Reproducibility tests showed low standard deviation (SD) of T2 values in regions of interest between scan and rescan (<0.4 msec) and across subjects (<4 msec).Data ConclusionGRAPPATINI provides highly reproducible and fast whole‐brain T2 maps and arbitrary synthetic T2‐w images in clinically compatible acquisition times of less than 2 minutes. These abilities are expected to support more widespread clinical applications of quantitative T2 mapping.Level of Evidence: 2Technical Efficacy: Stage 1J. MAGN. RESON. IMAGING 2018;48:359–368.
Nonbinary quantification technique accounting for myocardial infarct heterogeneity: Feasibility of applying percent infarct mapping in patients
Authors: Mastrodicasa Domenico , Elgavish Gabriel A. , Schoepf U. Joseph , Suranyi Pal , van Assen Marly , Albrecht Moritz H. , De Cecco Carlo N. , van der Geest Rob J. , Hardy Rayphael , Mantini Cesare , Griffith L. Parkwood , Ruzsics Balazs , Varga‐Szemes Akos 
Published: February 2018

BackgroundBinary threshold‐based quantification techniques ignore myocardial infarct (MI) heterogeneity, yielding substantial misquantification of MI.PurposeTo assess the technical feasibility of MI quantification using percent infarct mapping (PIM), a prototype nonbinary algorithm, in patients with suspected MI.Study TypeProspective cohortPopulationPatients (n = 171) with suspected MI referred for cardiac MRI.Field Strength/SequenceInversion recovery balanced steady‐state free‐precession for late gadolinium enhancement (LGE) and modified Look–Locker inversion recovery (MOLLI) T1‐mapping on a 1.5T system.AssessmentInfarct volume (IV) and infarct fraction (IF) were quantified by two observers based on manual delineation, binary approaches (2–5 standard deviations [SD] and full‐width at half‐maximum [FWHM] thresholds) in LGE images, and by applying the PIM algorithm in T1 and LGE images (PIMT1; PIMLGE).Statistical TestIV and IF were analyzed using repeated measures analysis of variance (ANOVA). Agreement between the approaches was determined with Bland–Altman analysis. Interobserver agreement was assessed by intraclass correlation coefficient (ICC) analysis.ResultsMI was observed in 89 (54.9%) patients, and 185 (38%) short‐axis slices. IF with 2, 3, 4, 5SDs and FWHM techniques were 15.7 ± 6.6, 13.4 ± 5.6, 11.6 ± 5.0, 10.8 ± 5.2, and 10.0 ± 5.2%, respectively. The 5SD and FWHM techniques had the best agreement with manual IF (9.9 ± 4.8%) determination (bias 1.0 and 0.2%; P = 0.1426 and P = 0.8094, respectively). The 2SD and 3SD algorithms significantly overestimated manual IF (9.9 ± 4.8%; both P < 0.0001). PIMLGE measured significantly lower IF (7.8 ± 3.7%) compared to manual values (P < 0.0001). PIMLGE, however, showed the best agreement with the PIMT1 reference (7.6 ± 3.6%, P = 0.3156). Interobserver agreement was rated good to excellent for IV (ICCs between 0.727–0.820) and fair to good for IF (0.589–0.736).Data ConclusionThe application of the PIMLGE technique for MI quantification in patients is feasible. PIMLGE, with its ability to account for voxelwise MI content, provides significantly smaller IF than any thresholding technique and shows excellent agreement with the T1‐based reference.Level of Evidence: 2Technical Efficacy: Stage 1J. Magn. Reson. Imaging 2018;48:788–798.
Geophysical and geochemical constraints on the age and paleoclimate implications of Holocene lacustrine cores from the Andes of central Chile
Authors: Tiner Rachel J. , Negrini Robert M. , Antinao Jose L. , McDonald Eric , Maldonado Antonio 
Published: February 2018

ABSTRACTA Holocene paleoclimate record was constructed using two lacustrine cores from the high‐elevation Chilean Andes at ∼30°S latitude. Coarser and more poorly sorted grain‐size distributions and higher C/N ratios were interpreted as evidence for increased storm activity. Wet conditions prevailed from ∼10.8 to 9.5k cal a BP, then transitioned to dry conditions from ∼9.5 to 5.7k cal a BP interrupted by stormy conditions from ∼8.3 to 7.6k cal a BP. Wet conditions returned from ∼5.7k cal a BP to the present, interrupted by aridity from ∼4.1 to 2.2k cal a BP. This paleoclimate record is consistent with others from the region. The wet periods were probably caused by the influence of the Southern Westerlies, while dry conditions resulted from the influence of the Southeast Pacific Anticyclone. The increased storminess from ∼8.3 to 7.7k cal a BP may have been sourced from latitudinal shifts in the Intertropical Convergence Zone and subsequent weakening of the Westerlies, allowing the incursion of convective storms from east of the Andes. This sequence of events is consistent with synoptic conditions during modern easterly sourced storm activity. It is also consistent with modeling studies of the effect on the Southern Hemisphere of the rapid cooling of the North Atlantic Ocean during the 8.2‐ka event.
First identification and characterization of Borrobol‐type tephra in the Greenland ice cores: new deposits and improved age estimates
Authors: Cook Eliza , Davies Siwan M. , Guðmundsdóttir Esther R. , Abbott Peter M. , Pearce Nicholas J. G. 
Published: February 2018

ABSTRACTContiguous sampling of ice spanning key intervals of the deglaciation from the Greenland ice cores of NGRIP, GRIP and NEEM has revealed three new silicic cryptotephra deposits that are geochemically similar to the well‐known Borrobol Tephra (BT). The BT is complex and confounded by the younger closely timed and compositionally similar Penifiler Tephra (PT). Two of the deposits found in the ice are in Greenland Interstadial 1e (GI‐1e) and an older deposit is found in Greenland Stadial 2.1 (GS‐2.1). Until now, the BT was confined to GI‐1‐equivalent lacustrine sequences in the British Isles, Sweden and Germany, and our discovery in Greenland ice extends its distribution and geochemical composition. However, the two cryptotephras that fall within GI‐1e ice cannot be separated on the basis of geochemistry and are dated to 14358 ± 177 a b2k and 14252 ± 173 a b2k, just 106 ± 3 years apart. The older deposit is consistent with BT age estimates derived from Scottish sites, while the younger deposit overlaps with both BT and PT age estimates. We suggest that either the BT in Northern European terrestrial sequences represents an amalgamation of tephra from both of the GI‐1e events identified in the ice‐cores or that it relates to just one of the ice‐core events. A firm correlation cannot be established at present due to their strong geochemical similarities. The older tephra horizon, found within all three ice‐cores and dated to 17326 ± 319 a b2k, can be correlated to a known layer within marine sediment cores from the North Iceland Shelf (ca. 17179‐16754 cal a BP). Despite showing similarities to the BT, this deposit can be distinguished on the basis of lower CaO and TiO2 and is a valuable new tie‐point that could eventually be used in high‐resolution marine records to compare the climate signals from the ocean and atmosphere.
The importance of key floral bioactive compounds to honey bees for the detection and attraction of hybrid vegetable crops and increased seed yield
Authors: Mas Flore , Harper Aimee , Horner Rachael , Welsh Taylor , Jaksons Peter , Suckling David M 
Published: February 2018

AbstractBACKGROUNDCrop breeding programmes generally select for traits for improved yield and human consumption preferences. Yet, they often overlook one fundamental trait essential for insect‐pollinated crops: pollinator attraction. This is even more critical for hybrid plants that rely on cross‐pollination between the male‐fertile line and the male‐sterile line to set seeds. This study investigated the role of floral odours for honey bee pollination that could explain the poor seed yield in hybrid crops.RESULTSThe key floral bioactive compounds that honey bees detect were identified for three vegetable hybrid crops. It was found that 30% of the variation in bioactive compound quantities was explained by variety. Differences in quantities of the bioactive compounds triggered different degrees of olfactory response and were also associated with varied appetitive response. Correlating the abundance of each bioactive compound with seed yield, it was found that aldehydes such as nonanal and decanal can have a strong negative influence on seed yield with increasing quantity.CONCLUSIONUsing these methodologies to identify relevant bioactive compounds associated with honey bee pollination, plant breeding programmes should also consider selecting for floral traits attractive to honey bees to improve crop pollination for enhanced seed yield. © 2018 Society of Chemical Industry
Patterns of Posttraumatic Stress Disorder and Posttraumatic Growth Among Adolescents After the Wenchuan Earthquake in China: A Latent Profile Analysis
Authors: Zhou Xiao , Wu Xinchun , Zhen Rui 
Published: February 2018

AbstractPosttraumatic stress disorder (PTSD) and posttraumatic growth (PTG) often coexist in the survivors of traumatic events. The current study examined the coexisting patterns of PTSD and PTG using latent profile analysis in a sample of 591 adolescent survivors of the May 12, 2008 Wenchuan earthquake in China. Logistic regression analysis was used to examine the effects of traumatic exposure on specific coexisting patterns. A three‐class solution characterized by a growth group (39.6%), a low symptoms group (10.3%), and a coexistence group (50.1%) fitted the data best. Members of the low symptoms group were more likely to be male, odds ratio (OR) = 2.67, 95% CI [1.48, 4.81]; and adolescents in the coexistence group were more likely to be older, OR = 1.22, 95%CI [1.09, 1.37], and to have had experienced serious indirect exposure, OR = 1.07, 95% CI [1.02, 1.12], and posttraumatic fear, OR = 1.20, 95% CI [1.11, 1.31].
Siphonaxanthin, a Carotenoid From Green Algae, Inhibits Lipogenesis in Hepatocytes via the Suppression of Liver X Receptor α Activity
Authors: Zheng Jiawen , Li Zhuosi , Manabe Yuki , Kim Minji , Goto Tsuyoshi , Kawada Teruo , Sugawara Tatsuya 
Published: February 2018

AbstractNonalcoholic fatty liver disease (NAFLD) has shown an increasing morbidity in recent years. Here, we demonstrated that siphonaxanthin (SPX), a rare marine carotenoid, exhibits a strong inhibitory effect on aggravated hepatic lipogenesis in vitro and would be a promising candidate in the prevention and alleviation of NAFLD in the future. In this study, we conducted a preliminary assessment of the effect of SPX on hepatic lipogenesis by using the HepG2 cell line, derived from human liver cancer, as a model of the liver. SPX significantly suppressed the excess accumulation of triacylglycerol induced by liver X receptor α (LXRα) agonist by downregulating a nuclear transcription factor named sterol regulatory element‐binding protein‐1c and a set of related genes. Moreover, fatty acid translocase (CD36) and fatty acid‐binding protein‐1, which regulates fatty acid uptake, also exhibited significant decrease in transcriptional levels. Furthermore, we found that SPX blocked LXRα activation and would be a promising candidate for antagonist of LXRα.
Existence of solutions for a nonlinear simply supported beam equation
Authors: Saavedra Lorena 
Published: February 2018

This paper is devotedto prove the existence of one or multiple solutions for a family of nonlinear fourth‐order boundary value problems.We use several fixed point theorems, previously developed by the author and her coauthor, to prove the existence of solutions of some simply supported beam problems. To finish the work, a particular case is studied, and the existence of multiple solutions is proved for 2 different particular nonlinear functions.
Meningococcal conjugate vaccine safety surveillance in the Vaccine Safety Datalink using a tree‐temporal scan data mining method
Authors: Li Rongxia , Weintraub Eric , McNeil Michael M. , Kulldorff Martin , Lewis Edwin M. , Nelson Jennifer , Xu Stanley , Qian Lei , Klein Nicola P. , Destefano Frank 
Published: February 2018

AbstractPurposeThe objective of our study was to conduct a data mining analysis to identify potential adverse events (AEs) following MENACWY‐D using the tree‐temporal scan statistic in the Vaccine Safety Datalink population and demonstrate the feasibility of this method in a large distributed safety data setting.MethodsTraditional pharmacovigilance techniques used in vaccine safety are generally geared to detecting AEs based on pre‐defined sets of conditions or diagnoses. Using a newly developed tree‐temporal scan statistic data mining method, we performed a pilot study to evaluate the safety profile of the meningococcal conjugate vaccine Menactra® (MenACWY‐D), screening thousands of potential AE diagnoses and diagnosis groupings. The study cohort included enrolled participants in the Vaccine Safety Datalink aged 11 to 18 years who had received MenACWY‐D vaccination(s) between 2005 and 2014. The tree‐temporal scan statistic was employed to identify statistical associations (signals) of AEs following MENACWY‐D at a 0.05 level of significance, adjusted for multiple testing.ResultsWe detected signals for 2 groups of outcomes: diseases of the skin and subcutaneous tissue, fever, and urticaria. Both groups are known AEs following MENACWY‐D vaccination. We also identified a statistical signal for pleurisy, but further examination suggested it was likely a false signal. No new MENACWY‐D safety concerns were raised.ConclusionsAs a pilot study, we demonstrated that the tree‐temporal scan statistic data mining method can be successfully applied to screen broadly for a wide range of vaccine‐AE associations within a large health care data network.
Addressing water scarcity: cationic polyelectrolytes in water treatment and purification
Authors: Wilts Emily M , Herzberger Jana , Long Timothy E 
Published: February 2018

AbstractSynthetic cationic polyelectrolytes (CPEs) serve as coagulation and flocculation agents in wastewater treatment due to a synergy of inherent electrostatic interactions and hydrophilic properties. In wastewater treatment, CPEs act as coagulation and flocculation agents to aggregate impurities and enable water purification. New health and environmental‐related regulations provide motivation for government agencies and industrial companies to reuse wastewater. Chemical structure, molecular weight, charge density and functionality of CPEs provide tailorability for specific purification needs. Cationic polyacrylamides, ammonium‐based polymers, poly(allyldimethyl‐ammonium chloride) and epichlorohydrin/dimethylamine‐based polymers are the most common CPEs used as coagulation and flocculation agents because they are economical and water soluble with tunable charge densities at high molecular weights. Free radical polymerization, step‐growth polymerization and post‐polymerization modification methods afford each polymer system. This review highlights recent advancements in synthetic methods to yield CPEs, structure−property relationships as related to flocculation efficiency and a summary of their toxicity and environmental impact. © 2018 Society of Chemical Industry
Effects of short‐chain branches on strain‐induced polymer crystallization
Authors: Guan Xinchao , Wang Youhao , Wang Jiping , Wu Yixian , Hu Wenbing 
Published: February 2018

AbstractWe performed dynamic Monte Carlo simulations of a lattice polymer model to investigate strain‐induced crystallization behaviors of short‐chain branched polymers with variable sequence distributions, branch numbers and lengths, and their blending compositions with linear polymers. The results revealed that the branch density and distribution bring dominant effects. In the blends, there is no phase separation prior to crystallization, except that strain‐enhanced mixing is temporarily hindered by chain folding upon crystallization. Our observations shed lights onto the strain‐induced crystallization of short‐chain branched polymers. © 2018 Society of Chemical Industry
Synthesis of new ionic crosslinked polymer hydrogel combining polystyrene and poly(4‐vinyl pyridine) and its self‐healing through a reshuffling reaction of the trithiocarbonate moiety under irradiation of ultraviolet light
Authors: Dong Peng , Cui Kun , Xu Fang , Jiang Tao , Ma Zhi 
Published: February 2018

AbstractA new ionic crosslinked polymer hydrogel was achieved by the strategy of ionically crosslinking α,ω‐dibromide terminated polystyrene (Br‐PS‐Br) with poly(4‐vinyl pyridine) (P4VP) which was synthesized by reversible addition‐fragmentation chain transfer polymerization using a chain transfer agent containing a trithiocarbonate moiety. The moiety of trithiocarbonate was introduced into the crosslinked network to show the self‐healing characteristics. The chain structure and components of Br‐PS‐Br and P4VP were characterized through 1H NMR, gel permeation chromatography, Fourier transform IR spectroscopy and elemental analysis. The P4VP (Mn = 25 300 g mol−1) chains were crosslinked with Br‐PS‐Br (Mn = 2000 g mol−1) through the quaternization reaction to form a polymer network which was further crosslinked in acetonitrile by irradiation of UV light to fabricate a hydrogel. Such a hydrogel of P4VP/Br‐PS‐Br cut by a razor blade can be rapidly (1 h) and repeatedly (three times) healed through a reshuffling reaction of the trithiocarbonate moiety under irradiation by UV light. © 2018 Society of Chemical Industry
The reactions of O‐(4‐nitrophenyl) S‐aryl dithiocarbonates with anilines: Effects on the relative nucleofugality
Authors: Santos José G. , Gazitúa Marcela 
Published: February 2018

AbstractKinetic and high‐performance liquid chromatography studies were investigated for the reactions of S‐phenyl, S‐(4‐chlorophenyl), and S‐(4‐nitrophenyl) O‐(4‐nitrophenyl) dithiocarbonates with anilines. These were performed in the presence of 0.1M borate buffer in 44 wt% aqueous ethanol. For reactions of the 3 substrates, the mechanism is stepwise with 2 tetrahedral intermediates, one zwitterionic (T±), and the other anionic (T−), where the intermediate T− is formed by proton transfer from T± to the borate buffer. The nonleaving group is not passive, playing an important role in the relative nucleofugality of the groups, which depend largely on its electron withdrawing capability. The nucleofugacity of 4‐nitrophenolate ion and of 4‐nitrophenylthiolate from the same tetrahedral intermediate is similar, despite the differences in their basicities (3 pKa units). In the reactions of S‐(4‐nitrophenyl) O‐(4‐nitrophenyl) dithiocarbonate, the change of nucleophile from pyridines (only 4‐nitrophenolate ion is nucleofuge) to anilines (2 nucleofuges) shows that the nature of the amine impacts on the relative nucleofugality of groups.
Synthesis and characterization of multifunctional polyamide 1 using CO2 and urea via environment‐friendly method
Authors: Yuan Dandan , Xu Yuanting , Zhou Feng , Cai Xufu 
Published: February 2018

ABSTRACTThe polyamide 1 (PA1) containing the highest density of hydrogen bond and dipole was synthesized using carbon dioxide (CO2) and urea as raw materials under supercritical CO2 condition through environment‐friendly method. Three kinds of molecular weights of PA1 were prepared in this study to satisfy different application areas. The chemical structures of PA1 were characterized comprehensively by means of 1H and 13C NMR, Fourier transform infrared spectroscopy, elements analysis, intrinsic viscosity, and wide angle X‐ray diffraction. The thermal properties and glass transition temperature were measured by thermogravimetric analysis (TGA) and differential scanning calorimetry. The obtained products had intrinsic average molecular weights ranging from 1.29 × 103 to 1.29 × 104. And the thermal stability and glass transition temperature increased with the increasing of molecular weight. TGA results indicated that the temperatures of 5% and 10% weight loss were 378 and 395 °C, respectively and the maximum decomposition temperatures for the two stages were 416 and 457 °C for the highest molecular weight product. The PA1, a new family member of polyamides, was a potential multifunctional material and found applications as high‐performance material. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 853–859
Targeting Murine Mesenchymal Stem Cells to Kidney Injury Molecule-1 Improves Their Therapeutic Efficacy in Chronic Ischemic Kidney Injury
Authors: Zou Xiangyu , Jiang Kai , Puranik Amrutesh S. , Jordan Kyra L. , Tang Hui , Zhu Xiangyang , Lerman Lilach O. 
Published: February 2018

Abstract
Mesenchymal stem cells (MSC) have been experimentally used for kidney repair, but modest retention limits their efficacy. Cell-surface coating allows modulating MSC homing and interaction with target cells. We coated mouse adipose tissue-derived MSC with antibodies directed against kidney injury molecule-1 (ab-KIM1), which is upregulated in injured kidneys, and tested the hypothesis that this would enhance their therapeutic effects in ischemic kidney injury. Untreated MSC, ab-KIM1-coated MSC (KIM-MSC), or vehicle, were injected systemically into the carotid artery of 2-kidneys, 1-clip mice 2 weeks after surgery. MSC retention in different organs was explored 24 hours, 48 hours, or 2 weeks after injection. Renal volume, perfusion, and oxygenation were studied 2 weeks after injection using magnetic resonance imaging in vivo, and renal inflammation, apoptosis, capillary density, and fibrosis ex vivo. The ab-KIM1 coating had little effect on MSC viability or proliferation. The stenotic kidney showed upregulated KIM1 expression, selective homing, and greater retention of KIM-MSC compared to untreated MSC and compared to other organs. KIM-MSC-injected mice improved renal perfusion and capillary density, and attenuated oxidative damage, apoptosis, and fibrosis compared to mice treated with vehicle or with native MSC. In conclusion, MSC coating with ab-KIM1 increased their retention in the ischemic kidney and enhanced their therapeutic efficacy. This novel method may be useful to selectively target injured kidneys, and supports further development of strategies to enhance cell-based treatment of ischemic kidney injury.