bluuebunny/crossref_metadata_2025_split huggingface dataset:
Critical Influence of 5‐Hydroxymethylfurfural Aging and Decomposition on the Utility of Biomass Conversion in Organic Synthesis
Authors: Galkin Konstantin I. , Krivodaeva Elena A. , Romashov Leonid V. , Zalesskiy Sergey S. , Kachala Vadim V. , Burykina Julia V. , Ananikov Valentine P. 
Published: June 2016

AbstractSpectral studies revealed the presence of a specific arrangement of 5‐hydroxymethylfurfural (5‐HMF) molecules in solution as a result of a hydrogen–bonding network, and this arrangement readily facilitates the aging of 5‐HMF. Deterioration of the quality of this platform chemical limits its practical applications, especially in synthesis/pharma areas. The model drug Ranitidine (Zantac®) was synthesized with only 15 % yield starting from 5‐HMF which was isolated and stored as an oil after a biomass conversion process. In contrast, a much higher yield of 65 % was obtained by using 5‐HMF isolated in crystalline state from an optimized biomass conversion process. The molecular mechanisms responsible for 5‐HMF decomposition in solution were established by NMR and ESI‐MS studies. A highly selective synthesis of a 5‐HMF derivative from glucose was achieved using a protecting group at O(6) position.
Synthetic Nucleosomes Reveal that GlcNAcylation Modulates Direct Interaction with the FACT Complex
Authors: Raj Ritu , Lercher Lukas , Mohammed Shabaz , Davis Benjamin G. 
Published: June 2016

AbstractTranscriptional regulation can be established by various post‐translational modifications (PTMs) on histone proteins in the nucleosome and by nucleobase modifications on chromosomal DNA. Functional consequences of histone O‐GlcNAcylation (O‐GlcNAc=O‐linked β‐N‐acetylglucosamine) are largely unexplored. Herein, we generate homogeneously GlcNAcylated histones and nucleosomes by chemical post‐translational modification. Mass‐spectrometry‐based quantitative interaction proteomics reveals a direct interaction between GlcNAcylated nucleosomes and the “facilitates chromatin transcription” (FACT) complex. Preferential binding of FACT to GlcNAcylated nucleosomes may point towards O‐GlcNAcylation as one of the triggers for FACT‐driven transcriptional control.
Determination of the Preassembled Nucleating Units That Are Critical for the Crystal Growth of the Metal–Organic Framework CdIF‐4
Authors: Wagia Raghidah , Strashnov Ilya , Anderson Michael W. , Attfield Martin P. 
Published: June 2016

AbstractIdentifying the form and role of the chemical species that traverse the stages of crystallization is critical to understanding the formation process of coordination polymers. Herein, we report the combined use of in situ atomic force microscopy and mass spectrometry to identify preformed, complex, cadmium 2‐ethylimidazole containing solution species in the growth solution of the cadmium 2‐ethylimidazolate metal–organic framework CdIF‐4, and show that they are critical in the surface nucleation for the crystal growth of this material. Surface nucleation appears to be instigated by these [Cdx(CH3CO2)y(C5H7N2/C5H8N2)z]‐containing solution species and not by sole addition of the ligand molecules. The CH3CO2− or Cd(CH3CO2)2 groups of the former are substituted subsequently as the framework growth proceeds. Our greater understanding of such solution species and their role in crystallization will guide future syntheses of designed functional coordination polymers.
Thermally Induced Carbohydroxylation of Styrenes with Aryldiazonium Salts
Authors: Kindt Stephanie , Wicht Karina , Heinrich Markus R. 
Published: June 2016

AbstractThe radical carbohydroxylation of styrenes with aryldiazonium salts has been achieved under mild thermal conditions. A broad range of aryldiazonium salts was tolerated, and the reaction principle based on a radical–polar crossover mechanism could be extended to carboetherification as well as to a two‐step, metal‐free variant of the Meerwein arylation leading to stilbenes.
Direct Measurement of Single‐Molecule DNA Hybridization Dynamics with Single‐Base Resolution
Authors: He Gen , Li Jie , Ci Haina , Qi Chuanmin , Guo Xuefeng 
Published: June 2016

AbstractHerein, we report label‐free detection of single‐molecule DNA hybridization dynamics with single‐base resolution. By using an electronic circuit based on point‐decorated silicon nanowires as electrical probes, we directly record the folding/unfolding process of individual hairpin DNAs with sufficiently high signal‐to‐noise ratio and bandwidth. These measurements reveal two‐level current oscillations with strong temperature dependence, enabling us to determine the thermodynamic and kinetic properties of hairpin DNA hybridization. More importantly, successive, stepwise increases and decreases in device conductance at low temperature on a microsecond timescale are successfully observed, indicating a base‐by‐base unfolding/folding process. The process demonstrates a kinetic zipper model for DNA hybridization/dehybridization at the single base‐pair level. This measurement capability promises a label‐free single‐molecule approach to probe biomolecular interactions with fast dynamics.
Oxidation State 10 Exists
Authors: Yu Haoyu S. , Truhlar Donald G. 
Published: June 2016

AbstractIn a recent paper, Wang et al. found an iridium‐containing compound with a formal oxidation state of 9. This is the highest oxidation state ever found in a stable compound. To learn if this is the highest chemical oxidation state possible, Kohn–Sham density functional theory was used to study various compounds, including PdO42+, PtO42+, PtO3F22+, PtO4OH+, PtO5, and PtO4SH+, in which the metal has an oxidation state of 10. It was found that PtO42+ has a metastable state that is kinetically stable with a barrier height for decomposition of 31 kcal mol−1 and a calculated lifetime of 0.9 years. All other compounds studied would readily decompose to lower oxidation states.
The effect of the addition of poly(styrene‐co‐glycidyl methacrylate) copolymer on the properties of polylactide/poly(methyl methacrylate) blend
Authors: Anakabe Jon , Zaldua Huici Ane Miren , Eceiza Arantxa , Arbelaiz Aitor 
Published: June 2016

ABSTRACTThe effect of the addition of poly(styrene‐co‐glycidyl methacrylate) P(S‐co‐GMA) copolymer on the properties of melt blended polylactide/poly(methyl methacrylate) (PLA/PMMA) 80/20 (wt %) composition was studied. In the literature high ductility levels were achieved by melt blending PLA with different additives. However, the gained ductility was counter balanced with drastic drops in strength and modulus values. The novelty of this work was the preparation of PLA‐based blends with polylactide content higher than 75 wt % which showed an impact resistance value improvement of about 60% compared with the neat PLA and maintained similar tensile strength and modulus values as well as glass transition temperature to neat PLA. The addition of only 3 pph of copolymer to PLA/PMMA blend improved the impact resistance almost 100%. The chemical reaction between PLA/PMMA blend and P(S‐co‐GMA) copolymer were analyzed by FTIR, rotational rheometry, and GPC/SEC. Phase structure and morphology were studied by Differential Scanning Calorimetry and Scanning Electronic Microscopy. Tensile and impact properties as well as thermal stability were also studied. Results showed that as the amount of copolymer in the blend was increased then higher was average molecular weight and polydispersity index. After the addition of P(S‐co‐GMA) copolymer to the PLA/PMMA blend the impact resistance, elongation at break and thermal stability were improved while tensile strength and elastic modulus remained almost unaltered. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43935.
Poverty Measurement: We Know Less than Policy Makers Realize
Authors: Gibson John 
Published: June 2016

AbstractThere is a widespread policy interest in poverty estimates at both national and global level. There has been an explosion of poverty measurement in the last two decades enabled by the growing availability of household survey data. These measurements are used by policy‐makers to assess progress towards national and global goals for inclusive growth and poverty reduction. But the evidence base rests on shaky foundations, and policy‐makers may have undue confidence in poverty and inequality estimates. Many household surveys are poorly designed to measure monetary living standards and poverty in an era of rising affluence and urban transition. Some key problems in measuring food consumption, housing services and the cost of living are discussed here. Alternatives to monetary measurement, such as using questions on life satisfaction and happiness, also rest on shaky foundations.
Prognostic significance of S100A4 expression in stage II and III colorectal cancer: results from a population‐based series and a randomized phase III study on adjuvant chemotherapy
Authors: Boye Kjetil , Jacob Havjin , Frikstad Kari‐Anne M. , Nesland Jahn M. , Mælandsmo Gunhild M. , Dahl Olav , Nesbakken Arild , Flatmark Kjersti 
Published: June 2016

AbstractCurrent clinical algorithms are unable to precisely predict which colorectal cancer patients would benefit from adjuvant chemotherapy, and there is a need for novel biomarkers to improve the selection of patients. The metastasis‐promoting protein S100A4 predicts poor outcome in colorectal cancer, but whether it could be used to guide clinical decision making remains to be resolved. S100A4 expression was analyzed by immunohistochemistry in primary colorectal carcinomas from a consecutively collected, population‐representative cohort and a randomized phase III study on adjuvant 5‐fluorouracil/levamisole. Sensitivity to treatment with 5‐fluorouracil in S100A4 knockdown cells was investigated using 2D and 3D cell culture assays. Strong nuclear expression of S100A4 was detected in 19% and 23% of the tumors in the two study cohorts, respectively. In both cohorts, nuclear immunoreactivity was associated with reduced relapse‐free (P < 0.001 and P = 0.010) and overall survival (P = 0.046 and P = 0.006) in univariate analysis. In multivariate analysis, nuclear S100A4 was a predictor of poor relapse‐free survival in the consecutive series (P = 0.002; HR 1.9), but not in the randomized study. Sensitivity to treatment with 5‐fluorouracil was not affected by S100A4 expression in in vitro cell culture assays, and there was no indication from subgroup analyses in the randomized study that S100A4 expression was associated with increased benefit of adjuvant treatment with 5‐fluorouracil/levamisole. The present study confirms that nuclear S100A4 expression is a negative prognostic biomarker in colorectal cancer, but the clinical utility in selection of patients for adjuvant fluoropyrimidine‐based chemotherapy is limited.
Minimalistic Ditopic Ligands: An α‐S,N‐Donor‐Substituted Alkyne as Effective Intermetallic Conjugation Linker
Authors: Rüger Julia , Timmermann Christopher , Villinger Alexander , Hinz Alexander , Hollmann Dirk , Seidel Wolfram W. 
Published: June 2016

AbstractThe capability of donor‐substituted alkynes to link different metal ions in a side‐on carbon donor‐chelate coordination mode is extended from the donor centers S and P to the second period element N. The complex [Tp′W(CO)2{η2‐C2(S)(NHBn)}] (Tp′=hydrido‐tris(3,5‐dimethylpyrazolyl)borate, Bn=benzyl) bearing a terminal sulfur atom and a secondary amine substituent is accessible by a metal‐template synthesis. Subsequent deprotonation allowed the formation of remarkably stable heterobimetallic complexes with the [(η5‐C5H5)Ru(PPh3)] and the [Ir(ppy)2] moiety. Electrochemical and spectroscopic investigations (cyclic voltammetry, IR, UV/Vis, luminescence, EPR), as well as DFT calculations, and X‐ray structure determinations of the W–Ru complex in two oxidation states reveal a strong metal–metal coupling but also a limited delocalization of excited states.
Ring‐Shaped Phosphinoamido‐Magnesium‐Hydride Complexes: Syntheses, Structures, Reactivity, and Catalysis
Authors: Fohlmeister Lea , Stasch Andreas 
Published: June 2016

AbstractA series of magnesium(II) complexes bearing the sterically demanding phosphinoamide ligand, L−=Ph2PNDip−, Dip=2,6‐diisopropylphenyl, including heteroleptic magnesium alkyl and hydride complexes are described. The ligand geometry enforces various novel ring and cluster geometries for the heteroleptic compounds. We have studied the stoichiometric reactivity of [(LMgH)4] towards unsaturated substrates, and investigated catalytic hydroborations and hydrosilylations of ketones and pyridines. We found that hydroborations of two ketones with pinacolborane using various Mg precatalysts is very rapid at room temperature with very low catalyst loadings, and ketone hydrosilylation using phenylsilane is rapid at 70 °C. Our studies point to an insertion/σ‐bond metathesis catalytic cycle of an in situ formed “MgH2” active species.
Aluminium Diphosphamethanides: Hidden Frustrated Lewis Pairs
Authors: Styra Steffen , Radius Michael , Moos Eric , Bihlmeier Angela , Breher Frank 
Published: June 2016

AbstractThe synthesis and characterisation of two aluminium diphosphamethanide complexes, [Al(tBu)2{κ2P,P′‐Mes*PCHPMes*}] (3) and [Al(C6F5)2{κ2P,P′‐Mes*PCHPMes*}] (4), and the silylated analogue, Mes*PCHP(SiMe3)Mes* (5), are reported. The aluminium complexes feature four‐membered PCPAl core structures consisting of diphosphaallyl ligands. The silylated phosphine 5 was found to be a valuable precursor for the synthesis of 4 as it cleanly reacts with the diaryl aluminium chloride [(C6F5)2AlCl]2. The aluminium complex 3 reacts with molecular dihydrogen at room temperature under formation of the acyclic σ2λ3,σ3λ3‐diphosphine Mes*PCHP(H)Mes* and the corresponding dialkyl aluminium hydride [tBu2AlH]3. Thus, 3 belongs to the family of so‐called hidden frustrated Lewis pairs.
A Robust Metal–Organic Framework for Dynamic Light‐Induced Swing Adsorption of Carbon Dioxide
Authors: Li Haiqing , Martinez Marta Rubio , Perry Zachary , Zhou Hong‐Cai , Falcaro Paolo , Doblin Christian , Lim Seng , Hill Anita J. , Halstead Barry , Hill Matthew R. 
Published: June 2016

AbstractAdsorbents for CO2 capture need to demonstrate efficient release. Light‐induced swing adsorption (LISA) is an attractive new method to release captured CO2 that utilizes solar energy rather than electricity. MOFs, which can be tailored for use in LISA owing to their chemical functionality, are often unstable in moist atmospheres, precluding their use. A MOF is used that can release large quantities of CO2 via LISA and is resistant to moisture across a large pH range. PCN‐250 undergoes LISA, with UV flux regulating the CO2 desorption capacity. Furthermore, under UV light, the azo residues within PCN‐250 have constrained, local, structural flexibility. This is dynamic, rapidly switching back to the native state. Reusability tests demonstrate a 7.3 % and 4.9 % loss in both adsorption and LISA capacity after exposure to water for five cycles. These minimal changes confirm the structural robustness of PCN‐250 and its great potential for triggered release applications.
Individual mediodorsal thalamic neurons project to multiple areas of the rat prefrontal cortex: A single neuron‐tracing study using virus vectors
Authors: Kuramoto Eriko , Pan Shixiu , Furuta Takahiro , Tanaka Yasuhiro R. , Iwai Haruki , Yamanaka Atsushi , Ohno Sachi , Kaneko Takeshi , Goto Tetsuya , Hioki Hiroyuki 
Published: June 2016

ABSTRACTThe prefrontal cortex has an important role in a variety of cognitive and executive processes, and is generally defined by its reciprocal connections with the mediodorsal thalamic nucleus (MD). The rat MD is mainly subdivided into three segments, the medial (MDm), central (MDc), and lateral (MDl) divisions, on the basis of the cytoarchitecture and chemoarchitecture. The MD segments are known to topographically project to multiple prefrontal areas at the population level: the MDm mainly to the prelimbic, infralimbic, and agranular insular areas; the MDc to the orbital and agranular insular areas; and the MDl to the prelimbic and anterior cingulate areas. However, it is unknown whether individual MD neurons project to single or multiple prefrontal cortical areas. In the present study, we visualized individual MD neurons with Sindbis virus vectors, and reconstructed whole structures of MD neurons. While the main cortical projection targets of MDm, MDc, and MDl neurons were generally consistent with those of previous results, it was found that individual MD neurons sent their axon fibers to multiple prefrontal areas, and displayed various projection patterns in the target areas. Furthermore, the axons of single MD neurons were not homogeneously spread, but were rather distributed to form patchy axon arbors approximately 1 mm in diameter. The multiple‐area projections and patchy axon arbors of single MD neurons might be able to coactivate cortical neuron groups in distant prefrontal areas simultaneously. Furthermore, considerable heterogeneity of the projection patterns is likely, to recruit the different sets of cortical neurons, and thus contributes to a variety of prefrontal functions. J. Comp. Neurol. 525:166–185, 2017. © 2016 Wiley Periodicals, Inc.
Effect of Pradigastat, a Diacylglycerol Acyltransferase 1 Inhibitor, on the QTcF Interval in Humans
Authors: Meyers Charles D. , Noe Adele , Salunke Atish , Movva Aishwarya , Kulmatycki Kenneth , Neelakantham Srikanth , Crissey Anne , Majumdar Tapan , Chen Jin 
Published: June 2016

AbstractPradigastat, a novel diacylglycerol acyltransferase 1 inhibitor, has been studied in familial chylomicronemia syndrome. To evaluate the effects of supratherapeutic concentrations of pradigastat on the QTc interval, 2 studies were conducted. The first study assessed the safety, tolerability, and pharmacokinetics of single escalating intravenous doses of pradigastat (10, 30, 100, and 115 mg over 60 minutes) in healthy adults. Single intravenous doses were safe, well tolerated, and at the higher doses resulted in supratherapeutic pradigastat exposure. The second was a parallel, 3‐arm thorough QTc study in which healthy male subjects were randomized to pradigastat (115 mg intravenously), moxifloxacin (400 mg oral, positive control), or placebo. Following intravenous administration, pradigastat exposure peaked at 4 times the therapeutic concentration and did not prolong the baseline‐adjusted and placebo‐corrected QTc intervals. During the 60‐minute pradigastat infusion, a number of infusion reactions and a small mean decrease in QTc were observed. Both effects disappeared when the infusion was stopped, suggesting that an infusate excipient may have been responsible. As expected, moxifloxacin significantly increased the QTc interval at multiple points, confirming the study's sensitivity to detect a true positive effect. Pradigastat is therefore unlikely to increase the risk of dysrhythmias associated with QTc prolongation in humans.
A conceptual review of mate choice: stochastic demography, within‐sex phenotypic plasticity, and individual flexibility
Authors: Ah‐King Malin , Gowaty Patricia Adair 
Published: June 2016

AbstractMate choice hypotheses usually focus on trait variation of chosen individuals. Recently, mate choice studies have increasingly attended to the environmental circumstances affecting variation in choosers' behavior and choosers' traits. We reviewed the literature on phenotypic plasticity in mate choice with the goal of exploring whether phenotypic plasticity can be interpreted as individual flexibility in the context of the switch point theorem, SPT (Gowaty and Hubbell ). We found >3000 studies; 198 were empirical studies of within‐sex phenotypic plasticity, and sixteen showed no evidence of mate choice plasticity. Most studies reported changes from choosy to indiscriminate behavior of subjects. Investigators attributed changes to one or more causes including operational sex ratio, adult sex ratio, potential reproductive rate, predation risk, disease risk, chooser's mating experience, chooser's age, chooser's condition, or chooser's resources. The studies together indicate that “choosiness” of potential mates is environmentally and socially labile, that is, induced – not fixed – in “the choosy sex” with results consistent with choosers' intrinsic characteristics or their ecological circumstances mattering more to mate choice than the traits of potential mates. We show that plasticity‐associated variables factor into the simpler SPT variables. We propose that it is time to complete the move from questions about within‐sex plasticity in the choosy sex to between‐ and within‐individual flexibility in reproductive decision‐making of both sexes simultaneously. Currently, unanswered empirical questions are about the force of alternative constraints and opportunities as inducers of individual flexibility in reproductive decision‐making, and the ecological, social, and developmental sources of similarities and differences between individuals. To make progress, we need studies (1) of simultaneous and symmetric attention to individual mate preferences and subsequent behavior in both sexes, (2) controlled for within‐individual variation in choice behavior as demography changes, and which (3) report effects on fitness from movement of individual's switch points.
Frogs in the spotlight: a 16‐year survey of native frogs and invasive toads on a floodplain in tropical Australia
Authors: Brown Gregory P. , Shine Richard 
Published: June 2016

AbstractAlthough widespread declines in anuran populations have attracted considerable concern, the stochastic demographics of these animals make it difficult to detect consistent trends against a background of spatial and temporal variation. To identify long‐term trends, we need datasets gathered over long time periods, especially from tropical areas where anuran biodiversity is highest. We conducted road surveys of four anurans in the Australian wet–dry tropics on 4637 nights over a 16‐year period. Our surveys spanned the arrival of invasive cane toads (Rhinella marina), allowing us to assess the invader's impact on native anuran populations. Our counts demonstrate abrupt and asynchronous shifts in abundance and species composition from one year to the next, not clearly linked to rainfall patterns. Typically, periods of decline in numbers of a species were limited to 1–2 years and were followed by 1‐ to 2‐year periods of increase. No taxa showed consistent declines over time, although trajectories for some species showed significant perturbations coincident with the arrival of toads. None of the four focal frog species was less common at the end of the study than at the beginning, and three of the species reached peak abundances after toad arrival. Survey counts of cane toads increased rapidly during the initial stage of invasion but have subsequently declined and fluctuated. Distinguishing consistent declines versus stochastic fluctuations in anuran populations requires extensive time‐series analysis, coupled with an understanding of the shifts expected under local climatic conditions. This is especially pertinent when assessing impacts of specific perturbations such as invasive species.