bluuebunny/crossref_metadata_2025 huggingface dataset:
Probabilistic assessment of landslide tsunami hazard for the northern Gulf of Mexico
Authors: Pampell‐Manis A. , Horrillo J. , Shigihara Y. , Parambath L.
Published: January 2016

The devastating consequences of recent tsunamis affecting Indonesia and Japan have prompted a scientific response to better assess unexpected tsunami hazards. Although much uncertainty exists regarding the recurrence of large‐scale tsunami events in the Gulf of Mexico (GoM), geological evidence indicates that a tsunami is possible and would most likely come from a submarine landslide triggered by an earthquake. This study customizes for the GoM a first‐order probabilistic landslide tsunami hazard assessment. Monte Carlo Simulation (MCS) is employed to determine landslide configurations based on distributions obtained from observational submarine mass failure (SMF) data. Our MCS approach incorporates a Cholesky decomposition method for correlated landslide size parameters to capture correlations seen in the data as well as uncertainty inherent in these events. Slope stability analyses are performed using landslide and sediment properties and regional seismic loading to determine landslide configurations which fail and produce a tsunami. The probability of each tsunamigenic failure is calculated based on the joint probability of slope failure and probability of the triggering earthquake. We are thus able to estimate sizes and return periods for probabilistic maximum credible landslide scenarios. We find that the Cholesky decomposition approach generates landslide parameter distributions that retain the trends seen in observational data, improving the statistical validity and relevancy of the MCS technique in the context of landslide tsunami hazard assessment. Estimated return periods suggest that probabilistic maximum credible SMF events in the north and northwest GoM have a recurrence of 5000–8000 years, in agreement with age dates of observed deposits.
Reply to comment by Rashid et al. on “Asynchronous variation in the East Asian winter monsoon during the Holocene”
Authors: Jin Liya , Zhang Xiaojian , Leduc Guillaume
Published: January 2016

Rashid et al. (2016) questioned the use of the Mg‐/Ca‐based sea surface temperature (SST) data from the subpolar North Atlantic Ocean as well as the alkenone‐based SST data from the western tropical Indian Ocean we used to reflect the winter SSTs or regional changes in the Holocene SSTs. We first would like to reemphasize that the main message we wanted to convey in our article is that the East Asian winter monsoon (EAWM) strength decreased and then increased again during the Holocene but with a substantial lag in southern China as compared to northern China. We, of course, wanted to back up our model results with published SST data that may have detected such an asynchronous variation in the EAWM. For convenience, we used a series of proxy records extracted from the extended Global database for alkenone‐derived HOlocene Sea‐surface Temperature (GHOST) database that were initially intended to provide a template of Holocene SST trends for model/data comparison purpose (http://doi.pangaea.de/10.1594/PANGAEA.737370). Rashid et al. (2016) questioned our model/data comparison exercise, arguing that the data we present in Zhang et al. (2015a) cannot be used to track leads and lags in winter SSTs in the North Atlantic and northern Indian Ocean. Below we address point by point the issues raised by Rashid et al. (2016) and thank the authors for giving us the opportunity to sharpen our model/data comparison analysis.
Understanding climate change projections for precipitation over western Europe with a weather typing approach
Authors: Santos João A. , Belo‐Pereira Margarida , Fraga Helder , Pinto Joaquim G.
Published: January 2016

Precipitation over western Europe (WE) is projected to increase (decrease) roughly northward (equatorward) of 50°N during the 21st century. These changes are generally attributed to alterations in the regional large‐scale circulation, e.g., jet stream, cyclone activity, and blocking frequencies. A novel weather typing within the sector (30°W–10°E, 25–70°N) is used for a more comprehensive dynamical interpretation of precipitation changes. A k‐means clustering on daily mean sea level pressure was undertaken for ERA‐Interim reanalysis (1979–2014). Eight weather types are identified: S1, S2, S3 (summertime types), W1, W2, W3 (wintertime types), B1, and B2 (blocking‐like types). Their distinctive dynamical characteristics allow identifying the main large‐scale precipitation‐driving mechanisms. Simulations with 22 Coupled Model Intercomparison Project 5 models for recent climate conditions show biases in reproducing the observed seasonality of weather types. In particular, an overestimation of weather type frequencies associated with zonal airflow is identified. Considering projections following the (Representative Concentration Pathways) RCP8.5 scenario over 2071–2100, the frequencies of the three driest types (S1, B2, and W3) are projected to increase (mainly S1, +4%) in detriment of the rainiest types, particularly W1 (−3%). These changes explain most of the precipitation projections over WE. However, a weather type‐independent background signal is identified (increase/decrease in precipitation over northern/southern WE), suggesting modifications in precipitation‐generating processes and/or model inability to accurately simulate these processes. Despite these caveats in the precipitation scenarios for WE, which must be duly taken into account, our approach permits a better understanding of the projected trends for precipitation over WE.
Near‐neutral carbon dioxide balance at a seminatural, temperate bog ecosystem
Authors: Hurkuck Miriam , Brümmer Christian , Kutsch Werner L.
Published: January 2016

The majority of peatlands in the temperate zone is subjected to drainage and agricultural land use and have been found to be anthropogenic emission hot spots for greenhouse gases. At the same time, many peatlands receive increased atmospheric nitrogen (N) deposition by intensive agricultural practices. Here we provide eddy covariance measurements determining net ecosystem carbon dioxide (CO2) exchange at a protected but moderately drained ombrotrophic bog in Northwestern Germany over three consecutive years. The region is dominated by intensive agricultural land use with total (wet and dry) atmospheric N deposition being about 25 kg N ha−1 yr−1. The investigated peat bog was a small net CO2 sink during all three years ranging from −9 to −73 g C m−2 yr−1. We found temperature‐ and light‐dependent ecosystem respiration (Reco) and gross primary production, respectively, but only weak correlations to water table depths despite large interannual and seasonal variability. Significant short‐term effects of atmospheric N deposition on CO2 flux components could not be observed, as the primary controlling factors for N deposition and C sequestration, i.e., fertilization of adjacent fields as well as temperature and light availability, respectively, exceeded potential interactions between the two.
Comparative analysis of NOAA REFM and SNB3GEO tools for the forecast of the fluxes of high‐energy electrons at GEO
Authors: Balikhin M. A. , Rodriguez J. V. , Boynton R. J. , Walker S. N. , Aryan H. , Sibeck D. G. , Billings S. A.
Published: January 2016

Reliable forecasts of relativistic electrons at geostationary orbit (GEO) are important for the mitigation of their hazardous effects on spacecraft at GEO. For a number of years the Space Weather Prediction Center at NOAA has provided advanced online forecasts of the fluence of electrons with energy >2 MeV at GEO using the Relativistic Electron Forecast Model (REFM). The REFM forecasts are based on real‐time solar wind speed observations at L1. The high reliability of this forecasting tool serves as a benchmark for the assessment of other forecasting tools. Since 2012 the Sheffield SNB3GEO model has been operating online, providing a 24 h ahead forecast of the same fluxes. In addition to solar wind speed, the SNB3GEO forecasts use solar wind density and interplanetary magnetic field Bz observations at L1.The period of joint operation of both of these forecasts has been used to compare their accuracy. Daily averaged measurements of electron fluxes by GOES 13 have been used to estimate the prediction efficiency of both forecasting tools. To assess the reliability of both models to forecast infrequent events of very high fluxes, the Heidke skill score was employed. The results obtained indicate that SNB3GEO provides a more accurate 1 day ahead forecast when compared to REFM. It is shown that the correction methodology utilized by REFM potentially can improve the SNB3GEO forecast.
Evapotranspiration of rubber (Hevea brasiliensis) cultivated at two plantation sites in Southeast Asia
Authors: Giambelluca Thomas W. , Mudd Ryan G. , Liu Wen , Ziegler Alan D. , Kobayashi Nakako , Kumagai Tomo'omi , Miyazawa Yoshiyuki , Lim Tiva Khan , Huang Maoyi , Fox Jefferson , Yin Song , Mak Sophea Veasna , Kasemsap Poonpipope
Published: January 2016

To investigate the effects of expanding rubber (Hevea brasiliensis) cultivation on water cycling in Mainland Southeast Asia (MSEA), evapotranspiration (ET) was measured within rubber plantations at Bueng Kan, Thailand, and Kampong Cham, Cambodia. After energy closure adjustment, mean annual rubber ET was 1211 and 1459 mm yr−1 at the Thailand and Cambodia sites, respectively, higher than that of other tree‐dominated land covers in the region, including tropical seasonal forest (812–1140 mm yr−1), and savanna (538–1060 mm yr−1). The mean proportion of net radiation used for ET by rubber (0.725) is similar to that of tropical rainforest (0.729) and much higher than that of tropical seasonal forest (0.595) and savanna (0.548). Plant area index (varies with leaf area changes), explains 88.2% and 73.1% of the variance in the ratio of latent energy flux (energy equivalent of ET) to potential latent energy flux (LE/LEpot) for midday rain‐free periods at the Thailand and Cambodia sites, respectively. High annual rubber ET results from high late dry season water use, associated with rapid refoliation by this brevideciduous species, facilitated by tapping of deep soil water, and by very high wet season ET, a characteristic of deciduous trees. Spatially, mean annual rubber ET increases strongly with increasing net radiation (Rn) across the three available rubber plantation observation sites, unlike nonrubber tropical ecosystems, which reduce canopy conductance at high Rn sites. High water use by rubber raises concerns about potential effects of continued expansion of tree plantations on water and food security in MSEA.
Looking at Both Sides of the Coin: Mixed Representation Moderates Attribute‐framing Bias in Written and Auditory Messages
Authors: Kreiner Hamutal , Gamliel Eyal
Published: January 2016

Objects and events are often evaluated more favourably when presented in a positive frame than when presented in the complementary negative framing. Recent studies show that this attribute‐framing bias can be moderated when both positive and negative frames are represented in the message. Most attribute‐framing studies used written messages, although important messages are often conveyed auditorily. Unlike written messages, recipients cannot reread auditory messages and have to rely on their memory when evaluating them; consequently, the moderating effect of mixed representation may depend on memory constraints. The current study compared the framing bias in single‐attribute versus mixed‐attribute representations in written and auditory messages. In both written and auditory messages, single‐attribute representation yielded substantial framing bias whereas mixed‐attribute representation moderated the bias. The results are discussed in terms of the role of memory and attention in the attribute‐framing bias. Theoretical and practical implications are considered, and future research is suggested. Copyright © 2016 John Wiley & Sons, Ltd.
Model reference adaptive control for nonlinear switched systems under asynchronous switching
Authors: Xie Jing , Zhao Jun
Published: January 2016

In this paper, the problem of model reference adaptive control for nonlinear switched systems with parametric uncertainties is investigated. Asynchronous switching between subsystems and adaptive controllers is also considered. Firstly, a state feedback adaptive controller is designed. Then, sufficient conditions ensuring the global practical stability of the error switched system with average dwell time are proposed. The boundedness of all signals in the closed‐loop system is guaranteed by the proposed adaptive controller. Finally, a practical example is given to demonstrate the validity of the main results. Copyright © 2016 John Wiley & Sons, Ltd.
Large Nonclassical Electrostriction in (Y, Nb)‐Stabilized δ‐Bi2O3
Authors: Yavo Nimrod , Smith Alaric D. , Yeheskel Ori , Cohen Sydney , Korobko Roman , Wachtel Ellen , Slater Peter R. , Lubomirsky Igor
Published: January 2016

Classical electrostriction, describing a second‐order electromechanical response of insulating solids, scales with elastic compliance, S, and inversely with dielectric susceptibility, ε. This behavior, first noted 20 years ago by Robert Newnham, is shown to apply to a wide range of electrostrictors including polymers, glasses, crystalline linear dielectrics, and relaxor ferroelectrics. Electrostriction in fluorite ceramics of (Y, Nb)‐stabilized δ‐Bi2O3 is examined with 16%–23% vacant oxygen sites. Given the values of compliance and dielectric susceptibility, the electrostriction coefficients are orders of magnitude larger than those expected from Newnham's scaling law. In ambient temperature nanoindentation measurements, (Y, Nb)‐stabilized δ‐Bi2O3 displays primary creep. These findings, which are strikingly similar to those reported for Gd‐doped ceria, support the suggestion that ion conducting ceramics with the fluorite structure, a large concentration of anion vacancies and anelastic behavior, may constitute a previously unknown class of electrostrictors.
Spatially and Spectrally Resolved Narrowband Optical Absorber Based on 2D Grating Nanostructures on Metallic Films
Authors: Qu Yurui , Li Qiang , Gong Hanmo , Du Kaikai , Bai Songang , Zhao Ding , Ye Hui , Qiu Min
Published: January 2016

Two spatially and spectrally resolved narrowband absorbers based on 2D grating nanostructures (polymethylmethacrylate (PMMA) grating and gold grating) on metallic films are designed, fabricated, and characterized. For PMMA grating on a metallic film, the measured absorption bandwidth is 12 nm with a nearly 80% absorption at normal incidence. The transverse electric (TE) localized mode shows a calculated 3.5° angular width. The transverse magnetic (TM) resonant mode supports both a localized mode and a lattice mode. The TM lattice mode shows a calculated angular width of 0.75° and exhibits a large wavelength‐angle sensitivity of nearly 15 nm per degree and a large absorption‐angle sensitivity of 77.5% per degree. For gold grating on a metallic film, the measured absorption bandwidth is 40 nm with a nearly 70% absorption. Such spatially and spectrally resolved 2D nanostructure arrays with large angle sensitivities have potential applications in angle measurement, thermal emitters, optical filters, and biosensors.
Rational Design of TADF Polymers Using a Donor–Acceptor Monomer with Enhanced TADF Efficiency Induced by the Energy Alignment of Charge Transfer and Local Triplet Excited States
Authors: Nobuyasu Roberto S. , Ren Zhongjie , Griffiths Gareth C. , Batsanov Andrei S. , Data Przemyslaw , Yan Shouke , Monkman Andrew P. , Bryce Martin R. , Dias Fernando B.
Published: January 2016

The photophysics of thermally activated delayed fluorescence (TADF) in phenothiazine‐dibenzothiophene‐S,S‐dioxide (PTZ‐DBTO2) molecule is investigated in detail. First, it is shown that the proximity of local triplet excited states (3LE), e.g., 3D or 3A, above or below the DA charge transfer states (CT) is crucial for the efficiency of the TADF mechanism in PTZ‐DBTO2. This TADF emitter is then used as a monomer unit to design polymer materials with efficient TADF. The reverse intersystem crossing mechanism (RISC) that supports TADF is able to compete with internal conversion and triplet–triplet annihilation (TTA) in the polymer chains and generates efficient TADF emission in the polymer pristine films. Prototype devices with PTZ‐DBTO2 dispersed in 4,4′‐bis(N‐carbazolyl)‐2,2′‐biphenyl (CBP) host give excellent performance with EQE of ≈22% at low luminance (<100 cd m−2), for 100 cd m−2 the EQE is 19.4%. In the case of solution processed devices, using the novel TADF polymers, the performance is much lower, EQE ≈3.5% at 100 cd m−2, which is still the highest value for a polymer TADF system at useful brightness, yet reported. This results from a combination of weak charge transport properties in these materials and device fabrication methods that require further improvement. Nevertheless, these results pave the way to explore TADF in polymer light emitting diodes (PLEDs), using less costly deposition methods, such as spin‐coating and inkjet printing, which are more appropriate for large area deposition.
Palladium‐Catalyzed Selective CH Activation: A Simple Method to Synthesize C‐3 Site Arylated Quinoline Derivatives
Authors: He Yongqin , Wu Zhaoyang , Ma Chaowei , Zhou Xiaoqiang , Liu Xingxing , Wang Xiajun , Huang Guosheng
Published: January 2016

A novel protocol for the synthesis of 3‐arylated quinoline derivatives has been developed using silver carbonate (Ag2CO3) and dioxygen (O2) as the oxidants. In this method, quinolines acting as the parent reagent react with arenes under palladium acetate [Pd(OAc)2] catalysis along with 1‐adamantanecarboxylic acid (Adm). The combination of the 1‐adamantanecarboxylic acid ligand and the palladium catalyst is found to be an essential factor for achieving high activity and selectivity, and allows a wide range of 3‐arylquinoline derivatives to be obtained in high yields. Moreover, a relevant mechanism is proposed, revealing that un der the palladium(II) catalysis a migratory insertion to C‐3H of quinolines and insertion to the CH of arenes are key steps in this reaction. Mild reaction conditions and high selectivity of the reactive site provide potential for promising applications in drug discovery and functional materials.

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Stereocontrolled Construction of 3,4‐Dihydrocoumarin Scaffolds with a Quaternary Amino Acid Moiety via Chiral Squaramide‐Catalyzed Cascade Michael Addition/Lactonization Reaction
Authors: Wang Yuehua , Pan Jianping , Jiang Rongrong , Wang Youming , Zhou Zhenghong
Published: January 2016

An asymmetric tandem Michael addition–lactonization between ortho‐nitrovinylphenols and azalactones was investigated for constructing 3,4‐dihydrocoumarin backbones with a quaternary amino acid moiety. Under the catalysis of the chiral squaramide derived from L‐tert‐leucine, a wide range of substituted (E)‐2‐(2‐nitrovinyl)phenols and azalactones were well tolerated in this tandem reaction to provide the corresponding biologically significant 3,4‐dihydrocoumarin derivatives in excellent yields with high levels of diastereo‐ and enantioselectivity.

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Iodine‐Mediated Synthesis of Aromatic Thioethers with Aromatic Amines and Sulfonyl Hydrazides in High Regioselectivity via C(sp2)H Bond Functionalization
Authors: Pang Xiaobo , Xiang Likui , Yang Xiaodong , Yan Rulong
Published: January 2016

An iodine‐mediated synthesis of aromatic thioethers from aromatic amines and sulfonyl hydrazides via C(sp2)H bond functionalization and CS bond formation has been developed. In this procedure, various substituents on the sulfonyl hydrazides, such as alkyl, methoxyl, chloro, bromo and fluoro groups, and aromatic amines are tolerated in the thiolation which generates the desired products in moderate to good yields.

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Conversion of isopropanol and mixed alcohols to hydrocarbons using HZSM‐5 catalyst in the MixAlco™ process. Part 2: Studies at 5000 kPa (abs)
Authors: Taco‐Vasquez Sebastian , Holtzapple Mark T.
Published: January 2016

This study employed HZSM‐5 (SiO2/Al2O3 = 280 mol/mol) to produce hydrocarbons from reagent‐grade isopropanol and mixed alcohols made from lignocellulosic biomass (waste office paper and chicken manure) using the MixAlco™ process. All studies were performed at P = 5000 kPa (abs). The experiments were conducted in two sets: (1) vary temperature (300–450°C) at weight hourly space velocity (WHSV) = 1.92 h−1, and (2) vary WHSV (1.92–11.52 h−1) at T = 370°C. For isopropanol at higher temperatures, the olefins undergo more cracking reactions to produce smaller molecules and more aromatics. At low temperatures, the molecules have less energy so they do not crack and therefore form larger molecules. At T = 300°C, the carbon distribution is bimodal at C9 and C12, which shows trimerization and tetramerization of propene. At 300°C, propene was the only gas produced, cracking did not occur and therefore preserved high‐molecular‐weight molecules. For mixed alcohols, higher temperatures show significant catalyst deactivation; however, isopropanol did not show any catalyst deactivation. © 2016 American Institute of Chemical Engineers AIChE J, 62: 1707–1715, 2016
12th International CHARGE syndrome conference proceedings
Authors: Martin Donna M. , Salem‐Hartshorne Nancy , Hartshorne Timothy S. , Scacheri Peter C. , Hefner Margaret A.
Published: January 2016

The CHARGE Syndrome Foundation holds an International conference for families and professionals every other summer. In July, 2015, the 12th meeting was held in Schaumburg, Illinois, at the Renaissance Schaumburg Hotel. Day one of the 4‐day conference was dedicated to professionals caring for and researching various aspects of CHARGE, including education, medical management, animal models, and stem cell‐based approaches to understanding and treating individuals with CHARGE. Here, we summarize presentations from the meeting, including a synopsis of each of the three different breakout sessions (Medical/Clinical, Basic Science/CHD7, and Education), followed by a list of abstracts and authors for both platform and poster presentations. © 2016 Wiley Periodicals, Inc.
Autism spectrum disorder traits inSlc9a9knock‐out mice
Authors: Yang Lina , Faraone Stephen V. , Zhang‐James Yanli
Published: January 2016

Autism spectrum disorders (ASDs) are a group of neurodevelopmental disorders which begin in childhood and persist into adulthood. They cause lifelong impairments and are associated with substantial burdens to patients, families, and society. Genetic studies have implicated the sodium/proton exchanger (NHE) nine gene,Slc9a9, to ASDs and attention‐deficit/hyperactivity disorder(ADHD).Slc9a9encodes, NHE9, a membrane protein of the late recycling endosomes. The recycling endosome plays an important role in synapse development and plasticity by regulating the trafficking of membrane neurotransmitter receptors and transporters. Here we tested the hypothesis thatSlc9a9knock‐out (KO) mice would show ADHD‐like and ASD‐like traits. Ultrasonic vocalization (USV) recording showed thatSlc9a9KO mice emitted fewer calls and had shorter call durations, which suggest communication impairment.Slc9a9KO mice lacked a preference for social novelty, but did not show deficits in social approach;Slc9a9KO mice spent more time self‐grooming, an indicator for restricted and repetitive behavior. We did not observe hyperactivity or other behavior impairments which are commonly comorbid with ASDs in human, such as anxiety‐like behavior. Our study is the first animal behavior study that linksSlc9a9to ASDs. By eliminatingNHE9 activity, it provides strong evidence that lack ofSlc9a9leads to ASD‐like behaviors in mice and provides the field with a new mouse model of ASDs. © 2016 Wiley Periodicals, Inc.
Comparative Effectiveness of Prestroke Aspirin on Stroke Severity and Outcome
Authors: Park Jong‐Moo , Kang Kyusik , Cho Yong‐Jin , Hong Keun‐Sik , Lee Kyung Bok , Park Tai Hwan , Lee Soo Joo , Ko Youngchai , Han Moon‐Ku , Lee Jun , Cha Jae‐Kwan , Kim Dae‐Hyun , Kim Dong‐Eog , Kim Joon‐Tae , Choi Jay Chol , Yu Kyung‐Ho , Lee Byung‐Chul , Lee Ji Sung , Lee Juneyoung , Gorelick Philip B. , Bae Hee‐Joon ,   on the behalf of CRCS‐5 Investigators
Published: January 2016

Objective

The effect of prestroke aspirin use on initial severity, hemorrhagic transformation, and functional outcome of ischemic stroke is uncertain.

Methods

Using a multicenter stroke registry database, patients with acute ischemic stroke of three subtypes (large artery atherosclerosis [LAA], small vessel occlusion [SVO], or cardioembolism [CE]) were identified. NIH stroke scale (NIHSS) and hemorrhagic transformation at presentation and discharge modified Rankin Scale (mRS) were compared between prestroke aspirin users and nonusers.

Results

Among the 10,433 patients, 1,914 (18.3%) reported prestroke aspirin use. On crude analysis, initial NIHSS scores of aspirin users were higher than nonusers (mean difference: 0.35; 95% confidence interval [CI]: 0.04–0.66). However, a multivariable analysis with an application of inverse probability of treatment weighting based on a propensity score of prestroke aspirin, having an interaction effect of prestroke aspirin use and stroke subtype in the model, showed less stroke severity for aspirin users in LAA, but not in SVO and CE than for nonusers; mean difference in NIHSS scores in LAA was –0.97 (95% CI: –1.45 to –0.49). With respect to hemorrhagic transformation and mRS, no significant interaction effects were found. Prestroke aspirin use increased the risk of hemorrhagic transformation (adjusted odd ratio: 1.34; 95% CI: 1.05–1.73), but decreased the odds of the higher discharge mRS (0.86; 0.76–0.96).

Interpretation

Prestroke aspirin use may reduce initial stroke severity in atherothrombotic stroke and can improve functional outcome at discharge despite an increase of hemorrhagic transformation irrespective of stroke subtype. Ann Neurol 2016;79:560–568
Niedermolekulare PROTACs: neue Wege zum Abbau von Proteinen
Authors: Toure Momar , Crews Craig M.
Published: January 2016

Die heutigen, auf Inhibitoren basierenden Therapieansätze sind zwangsläufig eingeschränkt durch 1) die Notwendigkeit von hoher systemischer Exposition, um ausreichende In‐vivo‐Effekte zu gewährleisten, 2) mögliche Nebenwirkungen aufgrund von hohen In‐vivo‐Konzentrationen des Wirkstoffs und 3) die Notwendigkeit, an ein aktives Zentrum zu binden, und die damit einhergehende Einschränkung der zugänglichen Zielproteine. Ein alternativer Ansatz nutzt einen neuen, katalytischen Mechanismus, um die Funktion eines Proteins irreversibel zu hemmen: den induzierten Abbau des Proteins durch die Rekrutierung an die zelluläre Maschinerie zur Qualitätskontrolle. Frühere Proteinabbau‐Strategien hatten kein hohes therapeutisches Anwendungspotenzial, doch neue Studien zu niedermolekularen PROTACs (“Proteolysis Targeting Chimeras”) haben gezeigt, dass diese Technik den Abbau von mehreren verschiedenen Proteinklassen überaus effizient vermitteln kann.
Organocatalytic Strategy for the Enantioselective Cycloaddition to Trisubstituted Nitroolefins to Create Spirocyclohexene‐Oxetane Scaffolds
Authors: Monleón Alicia , Glaus Florian , Vergura Stefania , Jørgensen Karl Anker
Published: January 2016

The first catalytic enantioselective cycloaddition reaction to α,β,β‐trisubstituted nitroolefins is reported. For this purpose, nitroolefin oxetanes were employed in the reaction with 2,4‐dienals promoted by trienamine catalysis. This methodology provides a facile and efficient strategy for the synthesis of highly functionalized chiral spirocyclohexene‐oxetanes with two adjacent tetrasubstituted carbon atoms in high yields and excellent selectivities. This strategy also enabled access to chiral spirocyclohexene‐cyclobutanes and ‐azetidines. Additionally, the obtained scaffolds can undergo diverse transformations leading to complex structures with up to four stereocenters, and we demonstrate that the nitro group, under nucleophilic conditions, can be applied for ring‐opening of the oxetane.
Effects of co‐hard segments on the microstructure and properties thermoplastic poly(ether ester) elastomers
Authors: Hao Tonghui , Zhang Cheng , Hu Guo‐Hua , Jiang Tao , Zhang Qunchao
Published: January 2016

A thermoplastic poly(ether ester) elastomer (TPEE) is composed of polyester hard segments and polyether soft segments. Polyester and polyether segments are often homopolymer segments. This work aims at incorporating poly(butylene phthalate (PBP) as co‐hard segments in the hard segments of poly(butylene terephthalate) (PBT)‐b‐poly(tetramethylene oxide) (PTMO) thermoplastic elastomer, and investigating structures and properties of the resulting materials, denoted as (PBT‐co‐PBP)‐b‐PTMO. (PBT‐co‐PBP)‐b‐PTMO was synthesized from dimethyl terephthalate (DMT), dimethyl phthalate (DMP), PTMO (Mn = 1000 g/mol), and 1,4‐butanediol (BDO). The crystallinity of (PBT‐co‐PBP)‐b‐PTMO first decreased and then increased with increasing PBP content from 5% to 10% due to a decrease in the average sequence length of the PBT hard segments. Its elongation at break was increased by 200–350%. When the mass fractions of PBT and PBP were 42% and 8%, respectively, the (PBT‐co‐PBP)‐b‐PTMO showed the best performance in terms of permanent deformation, strength, and hardness whose values were 30%, 25 MPa, and 37 D, respectively. All the synthesized copolymers had good thermal stability with a decomposition temperature of 400°C or so. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43337.
Remote C−H Activation of Quinolines through Copper‐Catalyzed Radical Cross‐Coupling
Authors: Xu Jun , Shen Chao , Zhu Xiaolei , Zhang Pengfei , Ajitha Manjaly J. , Huang Kuo‐Wei , An Zhongfu , Liu Xiaogang
Published: January 2016

Achieving site selectivity in carbon–hydrogen (C−H) functionalization reactions is a formidable challenge in organic chemistry. Herein, we report a novel approach to activating remote C−H bonds at the C5 position of 8‐aminoquinoline through copper‐catalyzed sulfonylation under mild conditions. Our strategy shows high conversion efficiency, a broad substrate scope, and good toleration with different functional groups. Furthermore, our mechanistic investigations suggest that a single‐electron‐transfer process plays a vital role in generating sulfonyl radicals and subsequently initiating C−S cross‐coupling. Importantly, our copper‐catalyzed remote functionalization protocol can be expanded for the construction of a variety of chemical bonds, including C−O, C−Br, C−N, C−C, and C−I. These findings provide a fundamental insight into the activation of remote C−H bonds, while offering new possibilities for rational design of drug molecules and optoelectronic materials requiring specific modification of functional groups.
Evolution of translation initiation sequences using in vitro yeast ribosome display
Authors: Gan Rui , Jewett Michael C.
Published: January 2016

We report a novel in vitro yeast ribosome display method based on cell‐free protein synthesis (CFPS) using linear DNA templates. We demonstrate that our platform can enrich a target gene from a model library by 100‐fold per round of selection. We demonstrate the utility of our approach by evolving cap‐independent translation initiation (CITI) sequences, which result in a 13‐fold increase in CFPS yields after four rounds of selection, and a threefold further increase by placing the beneficial short sequences in tandem. We also show that 12 of the selected CITI sequences permit precise control of gene expression in vitro over a range of up to 80‐fold by enhancing translation (and not as cryptic promoters). These 12 sequences are then shown to tune protein expression in vivo, though likely due to a different mechanism. Looking forward, yeast ribosome display holds promise for evolving libraries of proteins and DNA regulatory parts for protein engineering and synthetic biology. Biotechnol. Bioeng. 2016;113: 1777–1786. © 2016 Wiley Periodicals, Inc.
Impact of body mass index on the outcomes following transcatheter aortic valve implantation
Authors: Abramowitz Yigal , Chakravarty Tarun , Jilaihawi Hasan , Cox Justin , Sharma Rahul P. , Mangat Geeteshwar , Nakamura Mamoo , Cheng Wen , Makkar Raj R.
Published: January 2016

Objectives

To investigate the influence of body mass index (BMI) on short‐ and midterm outcomes following transcatheter aortic valve implantation (TAVI).

Background

Although obesity is a major risk factor for cardiovascular mortality, numerous studies reported a beneficial effect of obesity on survival in patients with cardiovascular disease and in patients after cardiac interventions. Moreover, all previous reports examining the relation between BMI and outcomes following TAVI have underscored the “obesity paradox” in these patients.

Methods

During a 3 year period, 805 patients with severe aortic stenosis that underwent TAVI at our institute were evaluated. Based on baseline BMI, patients were classified as normal weight (18.5–24.9 kg/m2), overweight (25.0–29.9 kg/m2), or obese (≥30 kg/m2). TAVI endpoints, device success, and adverse events were considered according to the Valve Academic Research Consortium (VARC)−2 definitions.

Results

Obese patients were significantly younger, had higher prevalence of diabetes mellitus and chronic lung disease, and had lower prevalence of frailty. Device success was similar between the 3 groups. All‐cause mortality up to 30 days was 2.9% (10/340) vs 4.5% (12/268) vs 0.5% (1/186) in patients with normal weight, overweight, and obesity, respectively (p = 0.048). In a multivariable model, overweight and obese patients had similar overall mortality compared to patients with normal weight.

Conclusions

We found no evidence for the existence of an obesity paradox following TAVI. Correction for possible confounders such as frailty in the present cohort may explain the discrepancy between the current report and the previous reports that suggested a protective effect for increased BMI following TAVI. © 2016 Wiley Periodicals, Inc.
Impact of coronary artery calcification in percutaneous coronary intervention with paclitaxel‐eluting stents: Two‐year clinical outcomes of paclitaxel‐eluting stents in patients from the ARRIVE program
Authors: Lee Michael S. , Yang Tae , Lasala John , Cox David
Published: January 2016

Objectives

The purpose of this study was to evaluate clinical outcomes after percutaneous coronary intervention (PCI) in patients with coronary artery calcification (CAC).

Background

Smaller studies have reported worse clinical outcomes in patients with CAC who undergo PCI. The impact of CAC in the drug‐eluting stent era is unclear.

Methods

Data from 7,492 patients treated by PCI with ≥1 TAXUS Express stent in the ARRIVE registry with no inclusion/exclusion criteria were stratified by the severity of CAC, as determined by the operator. Endpoints were independently adjudicated. All major adverse cardiac events were assessed at 2 years.

Results

Moderate/severe CAC was present in 19.6%. The nil/mild CAC group had higher rate of current smokers. The moderate/severe CAC group was older and had a higher prevalence of hypertension, kidney disease, prior coronary artery bypass grafting, congestive heart failure, and left main disease. After adjustment for imbalanced baseline variables, patients with moderate/severe CAC had higher 2 year rates of major adverse cardiac events (18.3% vs 13.5%, p = 0.01) and death (10.3% vs 5.6%, p = 0.02).

Conclusions

Moderate/severe CAC was associated with increased clinical events in patients who underwent PCI with TAXUS stents. This may be explained in part due to differences important baseline characteristics including more patients with more comorbidities and more complex lesions. After adjustment for imbalanced baseline variables, the moderate/severe CAC group had a higher risk of major adverse cardiac events and death. Improvements in treatment strategies are needed for this high‐risk group of patients who undergo PCI. © 2016 Wiley Periodicals, Inc.
Exploring Scaling Relations for Chemisorption Energies on Transition‐Metal‐Exchanged Zeolites ZSM‐22 and ZSM‐5
Authors: Siahrostami Samira , Falsig Hanne , Beato Pablo , Moses Poul Georg , Nørskov Jens K. , Studt Felix
Published: January 2016

Copper exchange on all the different T sites of ZSM‐22 and ZSM‐5 is considered and the chemisorption energies of dioxygen, OH, and O species are studied. We show that for different T sites the adsorption energies vary significantly. The oxygen adsorption energy on copper‐exchanged zeolites is quite similar to those of the most selective catalysts for oxidation reactions, that is, Ag and Au surfaces. The chemisorption energies of oxygen, carbon‐, and nitrogen‐containing species on different transition metals exchanged in ZSM‐22 are also investigated. The study covers three different oxidation states, that is, 1+, 2+, and 3+ for the transition‐metal exchanges. Scaling relations are presented for the corresponding species. Chemisorption of O scales with chemisorption of OH for all three considered exchanges, whereas there are essentially rough correlations for NH2 and N as well as CH3 and C.
Unveiling the Oxidation Processes of Pt3Ni(1 1 1) by Real‐Time Surface Core‐Level Spectroscopy
Authors: Politano Antonio , Chiarello Gennaro
Published: January 2016

Pt3Ni(1 1 1) is the most efficient catalyst for the oxygen reduction reaction. Herein, we investigated the oxidation process of Pt3Ni(1 1 1) by time‐resolved X‐ray photoemission spectroscopy experiments with synchrotron radiation. For O2 exposure at room temperature, two well‐distinct O species are present with a sticking coefficient of 0.23–0.24 in the temperature range of interest for fuel‐cell technology. We show that the Pt skin of Pt3Ni(1 1 1) is selectively replaced by Ni2O3 and NiO surface‐skin layers upon heating in an O2 environment at 700 and 900 K, respectively. By dosing with O atoms, the formation of PtO is possible at 293 K, whereas Ni2O3 is formed at 353 K.
Insights into the Major Reaction Pathways of Vapor‐Phase Hydrodeoxygenation of m‐Cresol on a Pt/HBeta Catalyst
Authors: Sun Qianqian , Chen Guanyi , Wang Hua , Liu Xiao , Han Jinyu , Ge Qingfeng , Zhu Xinli
Published: January 2016

Conversion of m‐cresol was studied on a Pt/HBeta catalyst at 225–350 °C and ambient hydrogen pressure. At 250 °C, the reaction proceeds through two major reaction pathways: (1) direct deoxygenation to toluene (DDO path); (2) hydrogenation of m‐cresol to methylcyclohexanone and methylcyclohexanol on Pt, followed by fast dehydration on Brønsted acid sites (BAS) to methylcyclohexene, which is either hydrogenated to methylcyclohexane on Pt or ring‐contracted to dimethylcyclopentanes and ethylcyclopentane on BAS (HYD path). The initial hydrogenation is the rate‐determining step of the HYD path as its rate is significantly lower than those of subsequent steps. The apparent activation energy of the DDO path is 49.7 kJ mol−1 but the activation energy is negative for the HYD path. Therefore, higher temperatures lead to the DDO path becoming the dominant path to toluene, whereas the HYD path, followed by fast equilibration to toluene, is less dominant, owing to the inhibition of the initial hydrogenation of m‐cresol.
Kinetics of low‐temperature Fischer‐Tropsch synthesis on cobalt catalysts: Are both slurry autoclave and tubular packed‐bed reactors adequate to collect relevant data at lab‐scale?
Authors: Visconti Carlo Giorgio , Lietti Luca , Tronconi Enrico , Rossini Stefano
Published: January 2016

To verify the equivalence of kinetic data obtained in lab‐scale packed‐bed and slurry reactors for low‐temperature Fischer‐Tropsch synthesis over cobalt‐based catalysts, the same Co/γ‐Al2O3 catalyst was tested in both reactors, studying the effects of the process conditions (temperature, pressure, syngas composition, gas space velocity) on CO conversion rate and on product distribution. Then, both a lumped CO conversion rate equation and detailed kinetics (i.e. describing the rates of reactants conversion and product formation) were developed based on the data collected in the packed‐bed tubular reactor. The two models were finally used to simulate the performance of the slurry autoclave. By describing the slurry autoclave as a continuous stirred tank reactor and the packed‐bed as plug‐flow reactor, the kinetic information collected with the two reactors is fully equivalent and can be used indiscriminately to describe the rates of reactant consumption and product formation.
Improvement of Deduplication Efficiency by Two‐Layer Deduplication System
Authors: OGATA MIKITO , KOMODA NORIHISA
Published: January 2016

This paper proposes a two‐layer deduplication system for the backup process in an IT environment. The proposed system implements two chunk sizes in a descendent way and activates them simultaneously in a sequence. They eliminate duplicated parts among backup target data more efficiently than any conventional single‐layer deduplication system. The system weakens a substantial trade‐off between the deduplication rate and the performance, which is defined as the number of chunks reduced. Compared to a conventional approach, the proposed system provides an equivalent deduplication rate with much less performance degradation or more performance with less compensation of the deduplication rate. In addition, it achieves better stability of performance when small chunk sizes are used to manipulate heavily duplicated data and densely changed data. The positive effects of the proposed system are evaluated quantitatively and are compared to a conventional approach by using a simulation. The results are certified with a prototype machine.
Multiagent‐Based Electric Power Interchange between Microgrids
Authors: OKAMOTO KAZUYA , KURISU SHINYA , UTATANI MASAHIRO , NAGATA TAKESHI
Published: January 2016

In this paper, we propose a multiagent‐based electric power interchange method between microgrids (MGs). The proposed multiagent system consists of eight types of agent: a single micro virtual power plant (MVPP) agent , several MG controller agents (MGCs), several load agents, several gas turbine (gas engine) agents, several photovoltaic generation agents, several wind turbine generation agents, several battery agents, and a single grid agent. In the proposed system, the MVPP plays an important role, facilitating electric power exchange between MGCs. Simulation results suggest that the proposed multiagent system could improve the load factor and reduce the MG operation cost.
Cavitand Scission by Transition‐Metal Centres – Cleaved Cavitand Chirality and Its Consequences
Authors: Chavagnan Thierry , Sémeril David , Matt Dominique , Toupet Loïc , Harrowfield Jack , Welter Richard
Published: January 2016

Two molecules of the phosphine cavitand 5‐diphenylphosphanyl‐4(24),6(10),12(16),18(22)‐tetramethylenedioxy‐2,8,14,20‐tetrapentylresorcin[4]arene (1) each underwent cleavage of an O–CH2O bond when treated with 1 equiv. of [Ni(η5‐C5H5)(1,5‐cyclooctadiene)]BF4 to form a bis(phosphino–phenolato) complex (2) without a cyclopentadienyl ligand. The partially cleaved (P,O) ligands in 2 are chiral, and a single‐crystal X‐ray structure determination of 2 has shown that the complex molecule has close to twofold rotational symmetry with both ligand units in the same absolute configuration. As expected, the primary coordination sphere has a cis‐NiO2P2 geometry. In contrast, C–O bond breaking occurred only once per metal centre when 1 was treated with [RuBr2(p‐cymene)]2. This led to a crystallographically characterised complex [RuBr(P,O)(p‐cymene)] (4) along with a minor amount of a species (5) that is assumed to be a stereoisomer. Upon crystallisation of 4, two distinct types of crystals were isolated from the same solution; some of these were the racemic compound, while the others were the racemic conglomerate.
Hybrid Hierarchical Porous Silica Templated in Nanoemulsions for Drug Release
Authors: Riachy Philippe , Roig Ferran , García‐Celma Maria‐José , Stébé Marie‐José , Pasc Andrea , Esquena Jordi , Solans Conxita , Blin Jean Luc
Published: January 2016

A new nanocarrier for loading and releasing drugs is reported, and ketoprofen was used as a model drug. More precisely, the carrier is a hybrid material prepared by combining oil‐in‐water (O/W) nanoemulsions, into which the drug has been solubilized, with mesostructured silica. This organic–inorganic hybrid material shows a controlled release of the drug that is pH dependent. If the drug is impregnated into the bare hierarchical meso‐/macroporous dual silica material, obtained after the removal of the organic components by extraction, only 8 wt.‐% of ketoprofen is released in a phosphate buffer medium (pH 7.4), probably owing to its low solubility in the aqueous phase. The drug solubility and release are increased strongly by the addition of Pluronic micelles to the receptor phase; this suggests a micelle‐promoted and ‐assisted release mechanism. Whatever the vehicle, the release profiles of ketoprofen always follow the Korsmeyer–Peppas model with a diffusional release exponent value lower than 0.5, characteristic of a pseudo‐Fickian release mechanism. Moreover, the release of ketoprofen is better controlled from the hybrid nanocarrier than from the hierarchical bare porous silica.
Incorporation of the Constrained Peptidomimetic, 5‐Methylpyridin‐2‐one into Peptide Vinyl Sulfones and Peptide Epoxy Ketones is Detrimental for Proteasome Inhibition
Authors: Xin Bo‐Tao , de Bruin Gerjan , Plomp Jan‐Willem , Florea Bogdan I. , van der Marel Gijsbert A. , Overkleeft Herman S.
Published: January 2016

Human proteasomes are validated targets in oncology and are promising targets in immune related diseases. A number of peptide‐based proteasome inhibitors have reached the clinic and several others are currently investigated in clinical trials. Despite these achievements, peptide‐based inhibitors may be susceptible to protease‐mediated degradation. In this paper, we report on our results on the introduction of 5‐methylpyridin‐2‐one moiety in peptide vinyl sulfone and peptide epoxy ketone‐based proteasome inhibitors. Pyridin‐2‐ones have previously been used as constrained peptide isosteres capable to act as a hydrogen‐bond acceptor. Our results demonstrate that 5‐methylpyridin‐2‐one can be introduced into proteasome inhibitors, but that the activity of the resulting compounds is compromised compared to their parent peptide vinyl sulfones and peptide epoxy ketones.
The Light Emitter of the 2‐Coumar­anone Chemiluminescence: Theoretical and Experimental Elucidation of a Possible Model for Bioluminescent Systems
Authors: Schramm Stefan , Navizet Isabelle , Naumov Panče , Nath Naba K. , Berraud‐Pache Romain , Oesau Pascal , Weiss Dieter , Beckert Rainer
Published: January 2016

The bioluminescence reaction of many biological subspecies, most notably fireflies, forms dioxetanone derivatives as high‐energy intermediates. The thermal instability of dioxetanones complicates understanding of the transition from the ground state to the first excited state that leads to light emission. Herein, we report the reaction mechanism of 2‐coumaranones, synthetically accessible strongly chemiluminescent materials that mimic the bioluminescence reaction. The pathways of chemiexcitation and photorelaxation are clarified on the basis of synthetic evidence and spectrochemical as well as computational mechanistic analysis.