bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Spirocyclic Ethers by Enantioselective Copper‐Catalyzed Carboetherification of Alkenols
Authors: Karyakarte Shuklendu D. , Um Chanchamnan , Berhane Ilyas A. , Chemler Sherry R. 
Published: August 2018

AbstractSpirocyclic ethers can be found in bioactive compounds. This copper‐catalyzed enantioselective alkene carboetherification provides 5,5‐, 5,6‐ and 6,6‐spirocyclic products containing fully substituted chiral carbon centers with up to 99 % enantiomeric excess. This reaction features the formation of two rings from acyclic substrates, 1,1‐disubstituted alkenols functionalized with either arenes, alkenes, or alkynes, and clearly constitutes a powerful way to synthesize chiral spirocyclic ethers.
Nickel‐Catalyzed Amide Bond Formation from Methyl Esters
Authors: Ben Halima Taoufik , Masson‐Makdissi Jeanne , Newman Stephen G. 
Published: August 2018

AbstractDespite being one of the most important and frequently run chemical reactions, the synthesis of amide bonds is accomplished primarily by wasteful methods that proceed by stoichiometric activation of one of the starting materials. We report a nickel‐catalyzed procedure that can enable diverse amides to be synthesized from abundant methyl ester starting materials, producing only volatile alcohol as a stoichiometric waste product. In contrast to acid‐ and base‐mediated amidations, the reaction is proposed to proceed by a neutral cross coupling‐type mechanism, opening up new opportunities for direct, efficient, chemoselective synthesis.
Operando X‐Ray Absorption Spectroscopy Shows Iron Oxidation Is Concurrent with Oxygen Evolution in Cobalt–Iron (Oxy)hydroxide Electrocatalysts
Authors: Enman Lisa J. , Stevens Michaela Burke , Dahan Meir Haim , Nellist Michael R. , Toroker Maytal Caspary , Boettcher Shannon W. 
Published: August 2018

AbstractIron cations are essential for the high activity of nickel and cobalt‐based (oxy)hydroxides for the oxygen evolution reaction, but the role of iron in the catalytic mechanism remains under active investigation. Operando X‐ray absorption spectroscopy and density functional theory calculations are used to demonstrate partial Fe oxidation and a shortening of the Fe−O bond length during oxygen evolution on Co(Fe)OxHy. Cobalt oxidation during oxygen evolution is only observed in the absence of iron. These results demonstrate a different mechanism for water oxidation in the presence and absence of iron and support the hypothesis that oxidized iron species are involved in water‐oxidation catalysis on Co(Fe)OxHy.
Liquid polyoctahedral silsesquioxanes as an effective and facile reinforcement for liquid silicone rubber
Authors: Sun Jiaotong , Kong Junhua , He Chaobin 
Published: August 2018

ABSTRACTAcrylo polyoctahedral silsesquioxanes (POSS), a liquid POSS derivative with reactive C=C double bond, is used to modify addition‐cured liquid silicone rubber (LSR) as an effective nanofiller for the first time. Significant enhancements on mechanical properties are obtained. With addition of only 1.5 parts per hundred rubbers (phr) of acrylo POSS to fumed silica‐strengthened silicones, the Young's modulus and ultimate tensile strength are increased by 432% and 66%, respectively, and the hardness of resulting LSR composites is improved as well. Proton nuclear magnetic resonance and Fourier transform infrared spectroscopies prove the efficient hydrosilylation between Acrylo POSS and hydrosiloxane directly. The thermal stability and morphology investigations also confirm that POSS is covalently incorporated into the network of silicone rubber. The increment of crosslink density is proved by extraction and swelling experiment and dynamic mechanical analysis. It can be envisioned that this simple and effective method could help produce high performance silicone rubber composites. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 46996.
Lost in the labyrinth: Understanding idiosyncratic interpretations of Kubrick's The Shining
Authors: Merced Matthew 
Published: August 2018

AbstractStanley Kubrick's The Shining still generates intense interest nearly four decades after its release. There are numerous books, documentary films, websites, blogs, and YouTube videos dedicated to analyzing the film's content. Many of these analyses are wildly speculative. For example, the film is a coded confession by Kubrick that he faked the Apollo 11 moon landing footage. What about The Shining's content may contribute to some viewers generating such unusual interpretations? The present article applies psychoanalytic theory, supported by findings from cognitive science, to answer this question. It is argued that The Shining's ambiguity generates an “intolerance of uncertainty” for some viewers, which leads them to project their own beliefs and experiences onto the film's scenes and narrative. Additionally, the film's oedipally themed content evokes archaic associations that some viewers may struggle to integrate, which promotes cognitive regression to a less demanding mode of thought. Although this article focuses on a fictional film, its method and findings are potentially generalizable to other phenomena in which idiosyncratic interpretations are expressed.
3‐(7‐Azaindolyl)‐4‐indolylmaleimides as a novel class of mutant isocitrate dehydrogenase‐1 inhibitors: Design, synthesis, and biological evaluation
Authors: Hu Yuanyuan , Gao Anhui , Liao Honghui , Zhang Mengmeng , Xu Gaoya , Gao Lixin , Xu Lei , Zhou Yubo , Gao Jianrong , Ye Qing , Li Jia 
Published: August 2018

AbstractA series of 3‐(7‐azainodyl)‐4‐indolylmaleimides was designed, synthesized, and evaluated for their isocitrate dehydrogenase 1 (IDH1)/R132H inhibitory activities. Many compounds such as 11a, 11c, 11e, 11g, and 11s exhibited favorable inhibitory effects on IDH1/R132H and were highly selective against the wild‐type IDH1. Evaluation of the biological activities at the cellular level showed that compounds 11a, 11c, 11e, 11g, and 11s could effectively suppress the production of 2‐hydroxyglutaric acid in U87MG cells expressing IDH1/R132H. Preliminary structure–activity relationship (SAR) and molecular modeling studies were discussed based on the experimental data obtained. These findings may provide new insights into the development of novel IDH1/R132H inhibitors.
Durrington walls and the Stonehenge Hidden Landscape Project 2010–2016
Authors: Gaffney Vincent , Neubauer Wolfgang , Garwood Paul , Gaffney Christopher , Löcker Klaus , Bates Richard , De Smedt Phillipe , Baldwin Eamonn , Chapman Henry , Hinterleitner Alois , Wallner Mario , Nau Erich , Filzwieser Roland , Kainz Jakob , Trausmuth Tanja , Schneidhofer Petra , Zotti Georg , Lugmayer Agatha , Trinks Immo , Corkum Alexander 
Published: August 2018

AbstractSince 2010 the Stonehenge Hidden Landscapes Project (SHLP) has undertaken extensive archaeological prospection across much of the landscape surrounding Stonehenge. These remote sensing and geophysical surveys have revealed a significant number of new sites and landscape features whilst providing new information on many previously known monuments. The project goal to integrate multimethod mapping over large areas of the landscape has also provided opportunities to re‐interpret the landscape context of individual monuments and, in the case of the major henge at Durrington Walls, to generate novel insights into the structure and sequence of a monument which has attracted considerable research attention over many decades. This article outlines the recent work of the SHLP and the results of the survey at Durrington Walls that shed new light on this enigmatic monument including a site ‘hidden’ within the monument.
Deploying multispectral remote sensing for multi‐temporal analysis of archaeological crop stress at Ravenshall, Fife, Scotland
Authors: Moriarty Charles , Cowley Dave C. , Wade Tom , Nichol Caroline J. 
Published: August 2018

AbstractDiminishing returns of archaeological crop marks in lowland areas from traditional observer‐directed visible spectrum aerial survey with standard photographic cameras highlights a need to explore alternative approaches to maintain the effectiveness of survey programmes. Developments in low‐cost multispectral remote sensing have in part been driven by the growth of precision agriculture and, whilst contributing to the intensification of land use, these technologies may offer new spectral and temporal capacities for detecting, recording and monitoring historic landscapes. However, there are significant challenges to the deployment of such approaches, not least the costs of data acquisition and uncertainty about the best conditions for data collection. This study assesses the effectiveness of the Parrot Sequoia, a relatively low‐cost multispectral sensor recently developed for agricultural applications, for the detection of crop marks to inform archaeological survey. A series of observations were taken with the sensor mounted on an unmanned aerial vehicle (UAV) at Ravenshall, Fife, Scotland, between April and July 2017. The resulting reflectance maps are compared to red, green and blue (RGB) photographs taken with a Nikon D800E digital camera during seven light aircraft surveys, with the aim of testing the sensors' comparative ability to record crop mark developments over time. The contrast in reflectance between vegetation samples growing over buried archaeological remains and the surrounding field was assessed through separability in regional histogram values across different image band combinations. Separable values indicative of crop marks were found in both the multispectral and RGB results from June 2017 onwards. Several vegetation index (VI) maps, particularly the Simple Ratio (SR) and Normalised Difference Vegetation Index (NDVI), were found to be effective for distinguishing crop marks in the multispectral results. The Sequoia is a cost‐effective sensor offering improved spectral resolution over the RGB photographs, showing potential for subtle crop mark detection across compact study areas.
CBP/p300 inhibitor C646 prevents high glucose exposure induced neuroepithelial cell proliferation
Authors: Bai Baoling , Zhang Qin , Wan Chunlei , Li Dan , Zhang Ting , Li Huili 
Published: August 2018

BackgroundMaternal diabetes related neural tube defects (NTDs) are a result of oxidative stress and apoptosis. However, the molecular mechanism behind the pathogenesis is not fully understood. Here, we report that high glucose exposure‐induced epigenetic changes influence histone H4 acetylation and neuroepithelial cell proliferation. We also show that the acetyltransferase inhibitor C646 can prevent high glucose induced changes in histone H4 acetylation and neuroepithelial cell proliferation.MethodsBy using LC‐MS/MS as an unbiased approach, we screened the histone acetylation profile in an E9 neuroepithelial cell line (NE‐4C) under high glucose exposure. We further explored the mechanism in cells in vitro and in maternal diabetes‐induced mouse embryos in vivo.ResultsWe identified 35 core histone acetylation marks in normal E9 neuroepithelial cells, whereas high glucose exposure resulted in novel acetylation sites on H4K31 and H4K44. Acetylation levels of embryonic development associated H4K5/K8/K12/K16 increased in neuroepithelial cells exposed to high glucose in vitro and in brain tissue from maternal diabetes induced exencephalic embryos in vivo. Further, mRNA level of histone acetyltransferase CBP encoded gene Crebbp was significantly increased both in vitro and in vivo. The addition of C646, a selective inhibitor for CBP/p300, significantly rescued increase of H4K5/K8/K12/K16 acetylation levels and H3S10pi‐labeled neuroepithelial cell proliferation induced by high glucose exposure.ConclusionOur data provide complementary insights for potential mechanisms of maternal diabetes induced NTDs.
Functional connectivity changes in the entorhinal cortex of taxi drivers
Authors: Peng Limin , Zeng Ling‐Li , Liu Qiang , Wang Lubin , Qin Jian , Xu Huaze , Shen Hui , Li Hong , Hu Dewen 
Published: August 2018

AbstractIntroductionAs a major interface between the hippocampus and the neocortex, the entorhinal cortex (EC) is widely known to play a pivotal role in spatial memory and navigation. Previous studies have suggested that the EC can be divided into the anterior‐lateral (alEC) and the posterior‐medial subregions (pmEC), with the former receiving object‐related information from the perirhinal cortex and the latter receiving scene‐related information from the parahippocampal cortex. However, the functional connectivity maps of the EC subregions in the context of extensive navigation experience remain elusive. In this study, we analyzed the functional connectivity of the EC in subjects with long‐term navigation experience and aimed to find the navigation‐related change in the functional properties of the human EC.MethodsWe investigated the resting‐state functional connectivity changes in the EC subregions by comparing the EC functional connectivity maps of 20 taxi drivers with those of 20 nondriver controls. Furthermore, we examined whether the functional connectivity changes of the EC were related to the number of taxi driving years.ResultsSignificantly reduced functional connectivity was found in the taxi drivers between the left pmEC and the right anterior cingulate cortex (ACC), right angular gyrus, and bilateral precuneus as well as some temporal regions, and between the right pmEC and the left inferior temporal gyrus. Notably, the strength of the functional connectivity between the left pmEC and the left precuneus, as well as the right ACC, was negatively correlated with the years of taxi driving.ConclusionThis is the first study to explore the impact of long‐term navigation experience on the connectivity patterns of the EC, the results of which may shed new light on the potential influence of extensive navigational training on the functional organization of the EC in healthy human brains.
Altered physiological brain variation in drug‐resistant epilepsy
Authors: Kananen Janne , Tuovinen Timo , Ansakorpi Hanna , Rytky Seppo , Helakari Heta , Huotari Niko , Raitamaa Lauri , Raatikainen Ville , Rasila Aleksi , Borchardt Viola , Korhonen Vesa , LeVan Pierre , Nedergaard Maiken , Kiviniemi Vesa 
Published: August 2018

AbstractIntroductionFunctional magnetic resonance imaging (fMRI) combined with simultaneous electroencephalography (EEG‐fMRI) has become a major tool in mapping epilepsy sources. In the absence of detectable epileptiform activity, the resting state fMRI may still detect changes in the blood oxygen level‐dependent signal, suggesting intrinsic alterations in the underlying brain physiology.MethodsIn this study, we used coefficient of variation (CV) of critically sampled 10 Hz ultra‐fast fMRI (magnetoencephalography, MREG) signal to compare physiological variance between healthy controls (n = 10) and patients (n = 10) with drug‐resistant epilepsy (DRE).ResultsWe showed highly significant voxel‐level (p < 0.01, TFCE‐corrected) increase in the physiological variance in DRE patients. At individual level, the elevations range over three standard deviations (σ) above the control mean (μ) CVMREG values solely in DRE patients, enabling patient‐specific mapping of elevated physiological variance. The most apparent differences in group‐level analysis are found on white matter, brainstem, and cerebellum. Respiratory (0.12–0.4 Hz) and very‐low‐frequency (VLF = 0.009–0.1 Hz) signal variances were most affected.ConclusionsThe CVMREG increase was not explained by head motion or physiological cardiorespiratory activity, that is, it seems to be linked to intrinsic physiological pulsations. We suggest that intrinsic brain pulsations play a role in DRE and that critically sampled fMRI may provide a powerful tool for their identification.
Long‐term risk of cardiovascular mortality in lymphoma survivors: A systematic review and meta‐analysis
Authors: Boyne Devon J. , Mickle Alexis T. , Brenner Darren R. , Friedenreich Christine M. , Cheung Winson Y. , Tang Karen L. , Wilson Todd A. , Lorenzetti Diane L. , James Matthew T. , Ronksley Paul E. , Rabi Doreen M. 
Published: August 2018

AbstractCardiovascular disease has been identified as one of the late complications of cancer therapy. The purpose of this study was to quantify the long‐term risk of cardiovascular mortality among lymphoma survivors relative to that of the general population. A systematic review and meta‐analysis were conducted. Articles were identified in November 2016 by searching EMBASE, MEDLINE, and CINAHL databases. Observational studies were included if they assessed cardiovascular mortality in patients with lymphoma who survived for at least 5 years from time of diagnosis or if they had a median follow‐up of 10 years. A pooled standardized mortality ratio (SMR) was estimated using a DerSimonian and Laird random‐effects model. The Q and I2 statistics were used to assess heterogeneity. Funnel plots and Begg's and Egger's tests were used to evaluate publication bias. Of the 7450 articles screened, 27 studies were included in the systematic review representing 46 829 Hodgkin and 14 764 non‐Hodgkin lymphoma survivors. The pooled number of deaths attributable to cardiovascular disease among Hodgkin and non‐Hodgkin disease was estimated to be 7.31 (95% CI: 5.29‐10.10; I2 = 95.4%) and 5.35 (95% CI: 2.55‐11.24; I2 = 94.0%) times that of the general population, respectively. This association was greater among Hodgkin lymphoma survivors treated before the age of 21 (pooled SMR = 13.43; 95% CI: 9.22‐19.57; I2 = 78.9%). There was a high degree of heterogeneity and a high risk of bias due to confounding in this body of literature. Lymphoma survivors have an increased risk of fatal cardiovascular events compared to the general population and should be targeted for cardiovascular screening and prevention campaigns.
Targeting of AKT/ERK/CTNNB1 by DAW22 as a potential therapeutic compound for malignant peripheral nerve sheath tumor
Authors: Li Xiao‐Xiao , Zhang Shi‐Jie , Chiu Amy P. , Lo Lilian H. , Huang Jian , Rowlands Dewi K. , Wang Jinhui , Keng Vincent W. 
Published: August 2018

AbstractMalignant peripheral nerve sheath tumors (MPNSTs) are an aggressive form of soft tissue neoplasm with extremely poor prognosis and no effective medical options currently available. MPNSTs can occur either sporadically or in association with the neurofibromatosis type 1 (NF1) syndrome. Importantly, activation of RAS/RAF/MEK/ERK, PI3K/AKT/mTOR, and WNT/CTNNB1 signaling pathways has been reported in both NF1‐related and late‐stage sporadic MPNSTs. In this study, we found that DAW22, a natural sesquiterpene coumarin compound isolated from Ferula ferulaeoides (Steud.) Korov., could inhibit cell proliferation and colony formation in five established human MPNST cancer cell lines. Further molecular mechanism exploration indicated that DAW22 could target the main components in the MPNST tumorigenic pathways: namely suppress phosphorylation of AKT and ERK, and reduce levels of non‐phospho (active) CTNNB1. Using the xenograft mouse model transplanted with human MPNST cancer cell line, daily treatment with DAW22 for 25 days was effective in reducing tumor growth. These results support DAW22 as an alternative therapeutic compound for MPNST treatment by affecting multiple signaling transduction pathways in its disease progression.
Genomics‐Driven Discovery of a Symbiont‐Specific Cyclopeptide from Bacteria Residing in the Rice Seedling Blight Fungus
Authors: Niehs Sarah P. , Dose Benjamin , Scherlach Kirstin , Roth Martin , Hertweck Christian 
Published: August 2018

AbstractThe rice seedling blight fungus Rhizopus microsporus harbors endosymbiotic bacteria (Burkholderia rhizoxinica) that produce the virulence factor rhizoxin and control host development. Genome mining indicated a massive inventory of cryptic nonribosomal peptide synthetase (NRPS) genes, which have not yet been linked to any natural products. The discovery and full characterization of a novel cyclopeptide from endofungal bacteria is reported. In silico analysis of an orphan, symbiont‐specific NRPS predicted the structure of a nonribosomal peptide, which was targeted by LC‐MS/MS profiling of wild‐type and engineered null mutants. NMR spectroscopy and chemical derivatization elucidated the structure of the bacterial cyclopeptide. Phylogenetic analyses revealed the relationship of starter C domains for rare N‐acetyl‐capped peptides. Heptarhizin is produced under symbiotic conditions in geographically constrained strains from the Pacific clade; this indicates a potential ecological role of the peptide.
Hollow Mesoporous Organic Polymeric Nanospheres (HMOPNs)‐Supported Carbene Rovis Catalyst: Mesopore and Morphology‐Dependent Catalytic Performances in Asymmetric Organocascade
Authors: Teng Fei , Xie Guangxing , Zhang Li , Ma Xuebing 
Published: August 2018

AbstractIn view of the vital functions of mesopore and hydrophobicity of organic polymer in the mass transfer of reactants and enantioselectivity in heterogeneous asymmetric organocatalysis, a novel type of well‐shaped hollow mesoporous organic polymeric nanospheres (HMOPNs)‐supported triazolium carbene Rovis catalyst was developed for the first time by the copolymerization of styrene and vinylated triazoline on the surface of polystyrene nanosphere (PS), etching of PS template by THF and then trityl cation‐mediated oxidation. The as‐fabricated well‐shaped HMOPNs with mesoporous shell and thin shell thickness was proven to be highly active in asymmetric Michael/Stetter cascade with the higher yields and enantioselectivities than mesopore‐deficient polystyrene‐supported triazolium carbene Rovis catalyst (PS‐7), and achieve the same enantioselectivities as corresponding homogeneous triazolium carbene Rovis catalyst. The as‐fabricated mesopores in the shell of HMOPNs played an important role in enantioselectivity on the basis of the calculated transition state of Breslow intermediate. Moreover, the HMOPNs‐supported Rovis catalyst displayed good reusability and mechanical stability in batch repeated experiments.
Discovery of Layered Indium Hydroxide via a Hydroperoxyl Anion Coordinated Precursor at Room Temperature
Authors: Qiu Yaming , Lin Cong , Li Jian , Zhang Lei , Xu Le , Zhao Yifang , Du X. Xin , Wang Ligang , Pan Fengjuan , Liao Fuhui , Sun Junliang 
Published: August 2018

AbstractAll reported layered metal hydroxides have brucite‐like metal‐hydroxyl host layers, and the discovery of other types of layered metal hydroxides could significantly extend the layered metal hydroxide families, which is meaningful in both theory and applications. Here, through hydroperoxyl anion coordinated In3+ cations as a precursor, a new layered indium hydroxide was synthesized, where only a three‐dimensional cubic phase had existed before. The layer of the product exhibits an unusual structure where In(OH)6 octahedra share edges and vertexes with each other to form layers, which is completely different from the common edge‐sharing brucite‐like metal‐hydroxyl layers. By investigating the formation mechanism, the new layered structure is found to be formed by changing the traditional crystallization path through the hydroperoxyl anion coordinated intermediates. Many other new phases could also be discovered by following the same intrinsic principle.