bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rationalizing the Structural Variability of the Exocyclic Amino Groups in Nucleobases and Their Metal Complexes: Cytosine and Adenine
Authors: Fonseca Guerra Célia , Sanz Miguel Pablo J. , Cebollada Andrea , Bickelhaupt F. Matthias , Lippert Bernhard 
Published: July 2014

AbstractThe exocyclic amino groups of cytosine and adenine nucleobases are normally almost flat, with the N atoms essentially sp2 hybridized and the lone pair largely delocalized into the heterocyclic rings. However, a change to marked pyramidality of the amino group (N then sp3 hybridized, lone pair essentially localized at N) occurs during i) involvement of an amino proton in strong hydrogen bonding donor conditions or ii) with monofunctional metal coordination following removal of one of the two protons.
Taming Gold(I)–Counterion Interplay in the De‐aromatization of Indoles with Allenamides
Authors: Jia Minqiang , Cera Gianpiero , Perrotta Daniele , Monari Magda , Bandini Marco 
Published: July 2014

AbstractA careful interplay between the π electrophilicity of a cationic AuI center and the basicity of the corresponding counterion allowed for the chemo‐ and regioselective inter‐ as well as intramolecular de‐aromatization of 2,3‐disubstituted indoles with allenamides. The silver‐free bifunctional Lewis acid/Brønsted base complex [{2,4‐(tBu)2C6H3O}3PAuTFA] assisted the formation of a range of densely functionalized indolenines under mild conditions.
A Simple Assay for Quality Binders to Cucurbiturils
Authors: Vázquez Julián , Remón Patricia , Dsouza Roy N. , Lazar Alexandra I. , Arteaga Jesús F. , Nau Werner M. , Pischel Uwe 
Published: July 2014

AbstractA new approach towards the rapid identification of quality binders to cucurbiturils—those that combine high affinity with high selectivity for a particular homologue—was developed. The assay exploits macrocycle‐specific optical fingerprints (colorimetric or fluorimetric) of carefully selected indicators dyes. The screening of a guest library revealed known (e.g., adamantane derivatives) and new (e.g., terpenes) quality binders. The predictive power of the assay was underpinned by the modeling of the involved thermodynamic equilibria.
Chirality and Polarity in the f‐Block Borates M4[B16O26(OH)4(H2O)3Cl4] (M=Sm, Eu, Gd, Pu, Am, Cm, and Cf)
Authors: Polinski Matthew J. , Pace Kristen A. , Stritzinger Jared. T. , Lin Jian , Cross Justin N. , Cary Samantha K. , Cleve Shelley M. Van , Alekseev Evgeny V. , Albrecht‐Schmitt Thomas E. 
Published: July 2014

AbstractThe reactions of trivalent lanthanides and actinides with molten boric acid in high chloride concentrations result in the formation of M4[B16O26(OH)4(H2O)3Cl4] (M=Sm, Eu, Gd, Pu, Am, Cm, Cf). This cubic structure type is remarkably complex and displays both chirality and polarity. The polymeric borate network forms helical features that are linked via two different types of nine‐coordinate f‐element environments. The f–f transitions are unusually intense and result in dark coloration of these compounds with actinides.
High‐Resolution 3D Proton MRI of Hyperpolarized Gas Enabled by Parahydrogen and Rh/TiO2 Heterogeneous Catalyst
Authors: Kovtunov Kirill V. , Barskiy Danila A. , Coffey Aaron M. , Truong Milton L. , Salnikov Oleg G. , Khudorozhkov Alexander K. , Inozemtseva Elizaveta A. , Prosvirin Igor P. , Bukhtiyarov Valery I. , Waddell Kevin W. , Chekmenev Eduard Y. , Koptyug Igor V. 
Published: July 2014

AbstractInvited for the cover of this issue is the group of Igor V. Koptyug at International Tomography Center; Valery I. Bukhtiyarov at Boreskov Institute of Catalysis of Russian Academy of Science; and Eduard Y. Chekmenev and Kevin W. Waddell at Vanderbilt University Institute of Imaging Science, Nashville. The image depicts the synthesis of hyperpolarized propane gas using parahydrogen‐induced polarization on the surface of a heterogeneous solid‐phase Rh catalyst, which enables very high‐resolution 3D magnetic resonance imaging of flowing propane gas. Read the full text of the article at 10.1002/chem.201403604.
Affordable Enteric Virus Detection Techniques Are Needed to Support Changing Paradigms in Water Quality Management
Authors: Symonds Erin M. , Breitbart Mya 
Published: July 2014

AbstractIn light of water quality monitoring paradigms shifting to a more holistic approach, it is essential that environmental microbiologists embrace new methodological developments in clinical virology to create rapid, laboratory‐free methods for the identification of wastewater pollution. It is widely accepted that routine monitoring of fecal indicator bacteria (FIB) does not adequately reflect human health risks associated with fecal pollution, especially risks posed by viruses. Enteric viruses are typically more resistant to wastewater treatment and persist longer in the environment than FIB. Furthermore, enteric viruses often have extremely low infectious doses. Currently, the incorporation of sanitary surveys, short‐term monitoring of reference pathogens, exploratory quantitative microbial risk assessments, and predictive ecological models is being championed as the preferred approach to water management. In addition to improved virus concentration methods, simple, point‐of‐use tests for enteric viruses and/or improved viral indicators are needed to complement this emerging paradigm and ensure microbial safety worldwide.
Effects of peginesatide injection on QTc interval in healthy adults
Authors: Czerniak Richard , Kukulka Michael , Wu Jing Tao , Qiu Ping 
Published: July 2014

AbstractA single‐dose, randomized, double‐blind, placebo‐ and positive‐controlled, three‐period crossover study was conducted to evaluate the effect of peginesatide injection on QT interval in healthy adults. Subjects received single doses of placebo, peginesatide injection 0.1 mg/kg intravenous, or moxifloxacin 400 mg during three treatment periods, separated by 14‐day washout intervals. ECG recordings and blood samples for peginesatide and moxifloxacin plasma concentrations were collected prior to dosing and through 22 hours postdose. QT intervals were measured with a high resolution manual on‐screen caliper method. The study endpoint was the mean difference between peginesatide and placebo in baseline‐adjusted corrected QT interval (ddQTc). The maximum upper bound of the one‐sided 95% CI was 2.2 milliseconds at 0.75 hours for Fridericia‐corrected ddQTc (ddQTcF) and 2.2 milliseconds at 0.25 hours for individual corrected ddQTcI. The linear relationship between ddQTcF and peginesatide concentrations was essentially flat and not statistically significant [slope = 0.001, P = 0.126, 90% CI: (<−0.0005, 0.002)]. Using this model, the projected ddQTcF effect at the observed mean peak plasma concentration is estimated to be 0.9 milliseconds, 90% CI: (−2.0, 0.3 milliseconds). There were no peginesatide‐related effects on heart rate, PR interval, or QRS interval. Thus, there is no anticipated cardiovascular effect of peginesatide injection 0.1 mg/kg in patients.
Oxytocin levels are lower in premenopausal women with type 1 diabetes mellitus compared with matched controls
Authors: Kujath Amber S. , Quinn Lauretta , Elliott Mary E. , Varady Krista A. , LeCaire Tamara J. , Carter C. Sue , Danielson Kirstie K. 
Published: July 2014

AbstractBackgroundOxytocin, a hormone most commonly associated with parturition and lactation, may have additional roles in diabetes complications. We determined oxytocin levels in premenopausal women with type 1 diabetes mellitus (T1DM) compared with non‐diabetic controls and examined associations of oxytocin with health behaviours, clinical factors, biomarkers, kidney function and bone health. Lower oxytocin was hypothesized for T1DM.MethodsA cross‐sectional study of premenopausal women with T1DM (n = 88) from the Wisconsin Diabetes Registry Study, a population‐based cohort of incident T1DM cases, and matched non‐diabetic controls (n = 74) was conducted.ResultsWomen with T1DM had lower oxytocin levels than controls adjusting for caffeine and alcohol use (p = 0.03). Health behaviours associated with oxytocin differed between women with and without T1DM: oxytocin was negatively associated with hormonal contraceptive use (quantified as lifetime contraceptive oestrogen exposure) in women with T1DM (p = 0.003), whereas positively related to hormonal contraceptive use (quantified as never/former/current) in controls (p < 0.001). Oxytocin had a positive association with adiposity (waist‐to‐hip ratio and leptin) in women with T1DM and a negative relationship with adiposity (weight gain) in controls. In T1DM only, oxytocin was positively associated with caffeine intake (p = 0.01) and negatively associated with alcohol use (p = 0.01). Oxytocin was not related to glycemic control, kidney function or bone health in T1DM.ConclusionsOxytocin levels are lower in women with T1DM than matched controls. Oxytocin also has opposing associations with hormonal contraceptives and adiposity in women with and without T1DM. Research is needed to determine if the altered oxytocin milieu in T1DM is associated with oxytocinher health outcomes. Copyright © 2014 John Wiley & Sons, Ltd.
Temporal and spatial dynamics of amphioxus population (Branchiostoma belcheri tsingtaneuse) and its influential factors in Luan River Estuary, China
Authors: Hao Luo , Minghui Ma , Bin Liang , Chenguang Bao 
Published: July 2014

AbstractPopulation distribution of amphioxus (Branchiostoma belcheri tsingtauense) was investigated in the Luan River Estuary from 1999 to 2011, to describe its trends and discover the factors that influence its decline. Amphioxus are distributed on the seabed at 5–10 m depth, between the Xinkai Estuary and the Dapu River Estuary, where the primary sand components of the sediment are medium and fine, with particle size ranging from 0.001 to 1 mm. In recent years, the population density and biomass of amphioxus have sharply decreased. Changes in sediment granularity composition may significantly influence amphioxus distribution. Our data showed that the highest density region of amphioxus occurred where >90% of the sediment particles were between 0.063 and 0.5 mm in size. A reduction in sediment discharge from Luan River and the expansion of raft‐breeding mariculture may be causing the decline in amphioxus through habitat destruction.
Fog, fog drip, and streamflow in the Santa Cruz Mountains of the California Coast Range
Authors: Sawaske Spencer R. , Freyberg David L. 
Published: July 2014

AbstractThe onshore movement of marine fog is a common occurrence during summer months along much of the contiguous US Pacific Coast. Because the fog season tends to occur during the precipitation‐free dry season, any additional input of moisture or reduction in loss of moisture through evapotranspiration provided by the marine layer can be an important factor in local hydrologic systems. To quantify some of the effects of fog on regional dry‐season hydrology, a study site within the Santa Cruz Mountains of central California was established. The fog‐laden coastside and predominately fog‐free San Francisco Bay side of the study area provide an excellent opportunity to assess the impacts of the presence and absence of fog on ecohydrological processes. Streamflow, fog drip, and soil moisture were measured from May to September. Fog drip was essentially nonexistent on the bayside and highly variable on the coastside. Maximum rates and seasonal totals of drip occurred within stands of mature conifers (Sequoia sempervirensandPseudotsuga menziesii) along exposed, often windy ridgelines. Fog‐drip totals up to 961 mm were recorded over 2·5 months. Consequently, frequent infiltration events to depths of 23 cm were documented. Over the course of the study, soil moisture levels at high‐fog‐drip locations either increased or were equivalent to spring conditions at the onset of data collection. Increases of flow in coastside streams, under otherwise receding conditions, were found to coincide with fog and fog‐drip events. These results confirm that the presence of fog can significantly affect dry‐season hydrologic conditions of some coastal locations. Copyright © 2014 John Wiley & Sons, Ltd.
Spatiotemporal patterns of evapotranspiration along the North American east coast as influenced by multiple environmental changes
Authors: Yang Qichun , Tian Hanqin , Li Xia , Tao Bo , Ren Wei , Chen Guangsheng , Lu Chaoqun , Yang Jia , Pan Shufen , Banger Kamaljit , Zhang Bowen 
Published: July 2014

AbstractThe North American east coast has experienced significant land‐use and climate changes since the beginning of the 20th century. In this study, using the Dynamic Land Ecosystem Model 2.0 driven by time‐series input data of land use, climate and atmospheric CO2, we examined how these driving forces have affected the spatiotemporal trends and variability of evapotranspiration (ET) in this region during 1901–2008. Annual ET in the North American east coast during this period was 648.3 ± 38.6 mm/year and demonstrated an increasing trend. Factorial model simulations indicated that climate variability explained 76% of the inter‐annual ET variability. Although land‐use change only explained 16% of the ET temporal variability, afforestation induced the upward trend of ET and increased annual ET by 12.8 mm/year. Elevated atmospheric CO2 reduced annual ET by 0.84 mm, and its potential impacts under future atmospheric CO2 levels could be much larger than estimates for the historical 1901–2008 period. Climate change determined the spatial pattern of ET changes across the entire study area, whereas land‐use changes dramatically affected ET in watersheds with significant land conversions. In spite of the multiple benefits from afforestation, its impacts on water resources should be considered in future land‐use policy making. Elevated ET may also affect fresh water availability for the increasing social and economic water demands. Copyright © 2014 John Wiley & Sons, Ltd.
Use of Organomolybdenum Compounds for Promoted Hydrolysis of Phosphoester Bonds in Aqueous Media
Authors: Gomes Ana C. , Gamelas Carla A. , Fernandes José A. , Almeida Paz Filipe A. , Nunes Patrique , Pillinger Martyn , Gonçalves Isabel S. , Romão Carlos C. , Abrantes Marta 
Published: July 2014

AbstractThe dissolution of the indenyl (Ind) complex [{(η5‐Ind)Mo(CO)2(μ‐Cl)}2] (1) in N,N′‐dimethylformamide (DMF) gives the ring‐slipped complex [(η3‐Ind)Mo(CO)2Cl(DMF)2] (2). The aerial oxidation of 2 leads to the formation of the dinuclear oxomolybdenum(V) chloride [Mo2O2(DMF)4(μ‐O)2Cl2] (3). The structures of 2 and 3·DMF have been determined by single‐crystal X‐ray diffraction. Compounds 1 and 3 were examined as promoters of phosphoester bond hydrolysis in para‐nitrophenylphosphate (pNPP), which was used as a model substrate. The reactions were performed in aqueous solution at 55 °C and followed by 1H NMR spectroscopy. For assays performed with 30–100 mol‐% of 1 or 3 relative to pNPP, both compounds promote the production of para‐nitrophenol (pNPh) from pNPP. Compound 3 is especially active in promoting the hydrolytic cleavage of the phosphoester bond (t1/2 < 80 min).
Close Correlation between Metal Oxidation States and Molecular Structures in a Cobalt–Gold Multinuclear Coordination System with Mixed D‐Penicillaminate and Tripodal Triphosphine
Authors: Hashimoto Yuji , Yoshinari Nobuto , Matsushita Natsuko , Konno Takumi 
Published: July 2014

AbstractA unique cobalt–gold coordination system, in which the oxidation states of the cobalt centers are closely correlated with the multinuclear molecular structures, is reported. This system contains a CoII3AuI6 nonanuclear structure in [Co3{Au3(tdme)(D‐pen‐N,O,S)3}2] ([2]) and a CoIIIAuI3 tetranuclear structure in [Co{Au3(tdme)(D‐pen‐N,S)3}] ([3]) [tdme = 1,1,1‐tris(diphenylphosphinomethyl)ethane, D‐pen = D‐penicillamininate], which are stereoselectively prepared from the reaction of a tripod‐type trigold(I) metalloligand [Au3(tdme)(D‐pen)3]3– ([1]3–) with Co2+ and Co3+, respectively. The anomalous stability of the +II oxidation state of each octahedral cobalt center in [2], despite the coordination of two aliphatic amine and two aliphatic thiolato groups that commonly provide a strong ligand field, is notable.
Ruthenium‐Catalyzed Synthesis of 1,2‐Diketones from Alkynes
Authors: Miao Yanan , Dupé Antoine , Bruneau Christian , Fischmeister Cédric 
Published: July 2014

AbstractThe ruthenium‐catalyzed synthesis of 1,2‐diketones through the oxidation of alkynes by using sodium hypochlorite has been investigated. RuO4 was generated in situ from inexpensive RuCl3·xH2O, and NaOCl as the oxidant demonstrated high performance at room temperature in the solvent diethyl carbonate. A variety of diketones were prepared in good yields by using this environmentally friendly procedure.
Temporal and spatial aspects of experimental tonic pain: Understanding pain adaptation and intensification
Authors: Weissman‐Fogel I. , Dror A. , Defrin R. 
Published: July 2014

AbstractBackgroundThe underlying mechanisms of adaptations to pain are unclear. In order to explore whether central or peripheral mechanisms predominate, the effects of two centrally mediated phenomena – spatial summation of pain (SSP) and transcutaneous electrical nerve stimulation (TENS) – were examined. The effect of the degree of painfulness, rather than absolute stimulation intensity, was also examined.MethodsSeventeen participants received several series of individually adjusted tonic noxious‐heat stimuli (300 s), inducing an initial perceived pain of 2 (mild pain), 4 (moderate pain) and 6 (strong pain) on a visual analogue scale (VAS). The stimuli were administered to small (2.25 cm2) and large (9 cm2) areas to produce SSP and also during TENS treatment, during which 12 VAS ratings were obtained.ResultsAdaptation occurred during VAS‐2 stimulation and was minimal, followed by intensification during VAS‐4 stimulation, whereas VAS‐6 stimulation always induced pain intensification. TENS failed to produce analgesia and SSP did not affect adaptation but affected intensification. Stimulation temperatures affected the magnitude of adaptation and intensification within each degree of painfulness. The mathematical models that best fitted the time trend with VAS‐2 and VAS‐4 were linear, whereas a power function best fitted VAS‐6 stimulation.ConclusionsThe mathematical models and the lack of effect of SSP on adaptation suggest that its dominant component is peripheral. Whereas relative painfulness determines whether pain adaptation or intensification occurs (probably a defence mechanism), absolute stimulation intensities influence the magnitude of the effect. Pain intensification is differentially affected by probe size, depending upon the occurrence of initial adaptation.
Geometrically exact theory of contact interactions – a general approach with a special focus on curve‐tosurface contact
Authors: Konyukhov Alexander , Schweizerhof Karl 
Published: July 2014

AbstractGeometrically exact theory of contact interactions is aiming on the development of the unified geometrical formulation of computational contact algorithms for various geometrical situations of contacting bodies leading to contact pairs: surface‐to‐surface, curve‐to‐surface, point‐to‐surface, curve‐to‐curve, point‐to‐curve, point‐to‐point. The construction of the corresponding computational contact algorithms is considered in accordance with the geometry of contacting bodies in covariant and closed forms. These forms can be easily discretized within finite element methods independently of the order of approximation and, therefore, the result is straightforwardly applied within any further method: high order finite element methods, iso‐geometric finite element methods etc. Application for contact between bodies with iso‐ and anisotropic surface, for contact between cables and curvilinear beams is straightforward. Recent developments include the various approaches to describe the ”Curve‐to‐Surface” contact pair; and the “Solid Beam‐to‐Solid Beam” contact algorithm, fully resolving the problem of “parallel tangents” of “Curve‐to‐Curve” contact algorithm. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dual mortar methods for computational contact mechanics – overview and recent developments
Authors: Popp A. , Wall W. A. 
Published: July 2014

AbstractMortar‐based finite element discretization in computational contact mechanics has seen a great thrust of research activities over the last years. In this contribution, we review the most important features of the so‐called dual mortar finite element approach for finite deformation contact and friction. Advantageous properties of the devised algorithms comprise superior robustness as compared with the traditional node‐to‐segment (NTS) approach, the absence of any unphysical user‐defined parameters (e.g. penalty parameter), the integration of all types of nonlinearities into one single iteration loop and the possibility to condense the biorthogonal discrete Lagrange multipliers from the global system of equations. Beside this general overview, some recent developments are highlighted, such as improved consistency and robustness of dual mortar methods, investigations on efficient numerical integration schemes, an extension to second‐order interpolation as well as the combined treatment of contact and elastoplasticity. Several numerical examples are presented to illustrate the high quality of results obtained with the proposed methods. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Isogeometric contact: a review
Authors: De Lorenzis Laura , Wriggers Peter , Hughes Thomas J.R. 
Published: July 2014

AbstractThis paper reviews the currently available computational contact formulations within the framework of isogeometric analysis (IGA). As opposed to conventional Lagrange discretizations, IGA basis functions feature higher and tailorable inter‐element continuity, which translates into evident advantages for the description of interacting surfaces, especially in presence of large displacements and large sliding. This has recently motivated the proposal of several isogeometric contact treatments, based on different ways to incorporate the contact contribution into the variational form of a continuum mechanics problem and to formulate its discretized version. After a brief overview of conventional and isogeometric basis functions as well as conventional contact mechanics approaches, the available isogeometric contact formulations are examined. Attention is paid to the favorable and unfavorable features they share with their finite element counterparts, as well as to the consequences stemming from the use of IGA basis functions. The main needs for future research emerging from the current state of the art are outlined. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)