bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bayesian Decision‐Making with Application to Resource Allocation
Authors: Betancourt Brenda , Steorts Rebecca C. 
Published: January 2018

AbstractIn decision theory, we start with the end in mind – how does one use inference results to make decisions and what consequences do these decisions have? Such statistical decision problems are becoming increasingly important as data are readily available at our fingertips. We outline the fundamental ideas of loss for decision theoretic tasks, Bayesian point estimation, and both frequentist and Bayesian risks. We focus on the Bayesian approach to statistical decision‐making and show the connections to Bayesian point estimation, while also contrasting it with the frequentist approach. We illustrate the decision theoretic tasks on a resource allocation problem where one is faced with estimating the proportion of individuals affected by a disease. By performing Bayesian sensitivity analysis, we explore several solutions to this problem and discuss their practical implications.
Minimal Sufficient Balance – A Better Alternative to Minimization for Randomized Controlled Trials
Authors: Zhao Wenle 
Published: January 2018

AbstractWhen stratified randomization fails owing to the large number of strata, the minimization method proposed by Taves, Pocock, and Simon in the 1970s becomes the only effective method for balancing multiple baseline covariates across treatment groups in clinical trials. It uses deterministic or biased‐coin assignments to reduce the sum of treatment imbalances in the margins of multiple baseline covariates, no matter how small these imbalances are. Controversies over the use of minimization in randomized controlled trials focus on the lack of allocation randomness, which is the root of selection bias. Theminimal sufficient balancestrategy recently proposed by Zhaoet al. uses biased‐coin treatment assignments only when the baseline covariate imbalance is serious, and such a biased‐coin assignment can meaningfully reduce the imbalance. Otherwise, the complete random treatment assignment is applied in order to minimize treatment allocation predictability.
A Type of 1 nm Molybdenum Carbide Confined within Carbon Nanomesh as Highly Efficient Bifunctional Electrocatalyst
Authors: Cheng Zhihua , Fu Qiang , Han Qing , Xiao Yukun , Liang Yuan , Zhao Yang , Qu Liangti 
Published: January 2018

AbstractHighly efficient platinum‐alternative bifunctional catalysts by using abundant non‐noble metal species are of critical importance to the future sustainable energy reserves. Unfortunately, current electrocatalysts toward hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) are far from satisfactory because of lacking reasonable design and assembly protocols. A type of 1‐nm molybdenum carbide nanoparticles confined in mesh‐like nitrogen‐doped carbon (Mo2C@NC nanomesh) with high specific surface area is reported here. In addition to the superior ORR performance comparable to platinum, the catalyst offers a high HER activity with small Tafel slope of 33.7 mV dec−1 and low overpotential of 36 mV to reach −10 mA cm−2. Theoretical calculations indicate that the active sites of the catalyst are mainly located at Mo atoms adjacent to the N‐doped carbon layer, which contributes the high HER activity. These findings show the great potential of Mo2C species in wide electrocatalysis applications.
Thermally Activated Delayed Fluorescence Conjugated Polymers with Backbone‐Donor/Pendant‐Acceptor Architecture for Nondoped OLEDs with High External Quantum Efficiency and Low Roll‐Off
Authors: Yang Yike , Wang Shumeng , Zhu Yunhui , Wang Yanjie , Zhan Hongmei , Cheng Yanxiang 
Published: January 2018

AbstractMost thermally activated delayed fluorescence (TADF) emitters have to be doped in the host for fabricating efficient organic light‐emitting diodes (OLEDs) and always suffer from quick efficiency roll‐off at high brightness, which severely affect their commercial application in display and lighting fields. In the work, a series of the polymers are synthesized by copolymerization of two carbazole monomers and one acridine derivative monomer containing benzophenone acceptor group. The obtained polymers therefore possess a conjugated backbone with carbazole/acridine moieties and benzophenone pendant to form the twisted donor/acceptor structure. Consequently, the TADF features inherited from the acridine derivative are maintained and improved by managing the content of acridine derivative monomer in the polymers. Solution‐processed OLEDs obtained from using neat polymer films exhibit comparable performance with organic TADF small molecules, achieving a maximum external quantum efficiency (EQE) of 18.1% and a very slow roll‐off with EQE of 17.8% at the luminance of 1000 cd m−2.
3D Printing of Materials with Tunable Failure via Bioinspired Mechanical Gradients
Authors: Kokkinis Dimitri , Bouville Florian , Studart André R. 
Published: January 2018

AbstractMechanical gradients are useful to reduce strain mismatches in heterogeneous materials and thus prevent premature failure of devices in a wide range of applications. While complex graded designs are a hallmark of biological materials, gradients in manmade materials are often limited to 1D profiles due to the lack of adequate fabrication tools. Here, a multimaterial 3D‐printing platform is developed to fabricate elastomer gradients spanning three orders of magnitude in elastic modulus and used to investigate the role of various bioinspired gradient designs on the local and global mechanical behavior of synthetic materials. The digital image correlation data and finite element modeling indicate that gradients can be effectively used to manipulate the stress state and thus circumvent the weakening effect of defect‐rich interfaces or program the failure behavior of heterogeneous materials. Implementing this concept in materials with bioinspired designs can potentially lead to defect‐tolerant structures and to materials whose tunable failure facilitates repair of biomedical implants, stretchable electronics, or soft robotics.
Reversible CO2 Addition to a Si=O Bond and Synthesis of a Persistent SiO2–CO2 Cycloadduct Stabilized by a Lewis Donor–Acceptor Ligand
Authors: Rodriguez Ricardo , Alvarado‐Beltran Isabel , Saouli Jérémy , Saffon‐Merceron Nathalie , Baceiredo Antoine , Branchadell Vicenç , Kato Tsuyoshi 
Published: January 2018

AbstractThe donor‐stabilized sila‐β‐lactone 1 reacts with CO2 via a remarkable reversible [2+2]‐cycloaddition reaction to form the spiro‐cyclic silicon carbonate derivative 2. Furthermore, photolysis of 2 under pressure of CO2 affords the first persistent SiO2–CO2 cycloadduct 3, presenting a Si2O4‐like structure, which is stabilized by a Lewis donor–acceptor type ligand. As predicted by theoretical calculations, in marked contrast to the thermodynamically stable SiO2 dimer, the SiO2–CO2 mixed cycloadduct 3 is labile and readily releases CO2.
Silver(I)‐Catalyzed Widely Applicable Aerobic 1,2‐Diol Oxidative Cleavage
Authors: Zhou Zhong‐zhen , Liu Mingxin , Lv Leiyang , Li Chao‐Jun 
Published: January 2018

AbstractThe oxidative cleavage of 1,2‐diols is a fundamental organic transformation. The stoichiometric oxidants that are still predominantly used for such oxidative cleavage, such as H5IO6 , Pb(OAc)4 , and KMnO4 , generate stoichiometric hazardous waste. Herein, we describe a widely applicable and highly selective silver(I)‐catalyzed oxidative cleavage of 1,2‐diols that consumes atmospheric oxygen as the sole oxidant, thus serving as a potentially greener alternative to the classical transformations.
Palladium‐Catalyzed Asymmetric Aminohydroxylation of 1,3‐Dienes
Authors: Shen Hong‐Cheng , Wu Yu‐Feng , Zhang Ying , Fan Lian‐Feng , Han Zhi‐Yong , Gong Liu‐Zhu 
Published: January 2018

AbstractA PdII‐catalyzed asymmetric aminohydroxylation of 1,3‐dienes with N‐tosyl‐2‐aminophenols was developed by making use of a chiral pyridinebis(oxazoline) ligand. The highly regioselective reaction provides direct and efficient access to chiral 3,4‐dihydro‐2H‐1,4‐benzoxazines in high yield and enantioselectivity (up to 96:4 e.r.). The reaction employs readily available N‐tosyl‐2‐aminophenols as a unique aminohydroxylation reagent and is complementary to known asymmetric aminohydroxylation methods.
Fused‐Ring Formation by an Intramolecular “Cut‐and‐Sew” Reaction between Cyclobutanones and Alkynes
Authors: Deng Lin , Jin Likun , Dong Guangbin 
Published: January 2018

AbstractThe development of a catalytic intramolecular “cut‐and‐sew” transformation between cyclobutanones and alkynes to construct cyclohexenone‐fused rings is described herein. The challenge arises from the need for selective coupling at the more sterically hindered proximal position, and can be addressed by using an electron‐rich, but less bulky, phosphine ligand. The control experiment and 13C‐labelling study suggest that the reaction may start with cleavage of the less hindered distal C−C bond of cyclobutanones, followed by decarbonylation and CO reinsertion to enable Rh insertion at the more hindered proximal position.
Fe2Si5N8: Access to Open‐Shell Transition‐Metal Nitridosilicates
Authors: Bielec Philipp , Janka Oliver , Block Theresa , Pöttgen Rainer , Schnick Wolfgang 
Published: January 2018

AbstractHighly condensed nitridosilicates doped with Eu2+ or Ce3+ play an important role in saving energy by converting the blue light of (In,Ga)N‐LEDs. Although nitridosilicates are known for great structural variety based on covalent anionic Si‐N networks, elemental variety is restricted. Presenting a significant extension of the latter, this work describes a general access to open‐shell transition‐metal nitridosilicates. As a proof‐of‐principle, the first iron nitridosilicate, namely Fe2Si5N8, was prepared by exchanging Ca2+ in α‐Ca2Si5N8 applying a FeCl2 melt (salt metathesis). The title compound was analyzed by powder X‐ray diffraction, EDX, ICP‐OES, combustion analysis, TG/DSC, Mössbauer spectroscopy and magnetic susceptibility measurements. Furthermore, the structure of α‐Ca2Si5N8 was determined at 1073 and 1173 K confirming the anionic network of α‐Ca2Si5N8 providing possible migration pathways for the ion‐exchange reaction.
Implications of microwave drying using 915 MHz frequency on rice physicochemical properties
Authors: Smith Deandrae L. , Atungulu Griffiths G. , Sadaka Sammy , Rogers Stephen 
Published: January 2018

Background and objectivesHigh moisture content (MC) rough rice was dried using an industrial microwave (MW) operated at a frequency of 915 MHz, and the impacts of the drying on the rice physicochemical properties were investigated. The treatments were performed at MW power levels 5, 10, and 15 kW, treatment durations 4, 6, and 8 min and for rice at initial MC of 24% (w.b.) and bed thicknesses 5, 10, and 15 cm. Near infrared spectroscopy and a rapid visco‐analyzer were used to assess the milled rice protein content, surface lipid content (SLC), total color difference (TCD), and rice peak and final viscosities.FindingsThe effect of increasing MW specific energy was statistically significant for all of the responses studied. Increasing MW specific energy resulted in an increase in measured rice SLC, protein content, and final and peak viscosities. Responses increased to a maximum then decreased at specific energies over 800 kJ/kg‐grain. The opposite profile was true for TCD. The TCD decreased as a result of increasing MW specific energy to a trough at 533.33 kJ/kg‐grain then increased at specific energies over 600 kJ/kg‐grain. The effect of varying rice bed thicknesses was not statistically significant.ConclusionsIt is vital to select appropriate MW specific energy to maintain the rice physicochemical properties.Significance and noveltyUsing MW heating with a frequency at 915 MHz provides new avenues to scale up the MW heating technology for rice drying; this may allow rapid, one‐pass rice drying while maintaining important quality characteristics.
Variation in asparagine concentration in Nebraska wheat
Authors: Navrotskyi Sviatoslav , Baenziger Peter Stephen , Regassa Teshome , Guttieri Mary J. , Rose Devin J. 
Published: January 2018

Background and objectivesAcrylamide can be formed from asparagine during baking of wheat products. Therefore, evaluation of different wheat cultivars and environmental conditions is needed to assess the potential risk of acrylamide formation in baked products made from Nebraska wheats. Three widely grown wheat cultivars (Goodstreak, Camelot, Freeman) and seven experimental lines were grown at five locations in 2014. Due to the large environmental effect on asparagine concentration, the named cultivars were also evaluated at twelve locations in 2016.FindingsAsparagine concentration varied widely among samples (200–1,100 mg/kg). In 2014, the highest concentration of asparagine was measured in samples grown at a location where delayed harvest resulted in excess solar radiation. In 2016, the highest asparagine concentration was measured in wheat grains grown in a location that experienced high disease pressure. In pairwise comparisons among all 17 locations sampled, asparagine was generally lower in Freeman compared with Goodstreak and Camelot. Asparagine concentration was positively correlated with kernel size and weight (r = .37; p = .03).ConclusionsThe major differences in asparagine concentration were due to growing environment, although the cultivar Freeman may be a low asparagine accumulating genotype.Significance and noveltyConditions that are associated with elevated asparagine include delayed harvest, disease pressure, and larger kernel size.
Interrogating Protein Phosphatases with Chemical Activity Probes
Authors: Casey Garrett R. , Stains Cliff I. 
Published: January 2018

AbstractProtein phosphatases, while long overlooked, have recently become appreciated as drivers of both normal‐ and disease‐associated signaling events. As a result, the spotlight is now turning torwards this enzyme family and efforts geared towards the development of modern chemical tools for studying these enzymes are well underway. This Minireview focuses on the evolution of chemical activity probes, both optical and covalent, for the study of protein phosphatases. Small‐molecule probes, global monitoring of phosphatase activity through the use of covalent modifiers, and targeted fluorescence‐based activity probes are discussed. We conclude with an overview of open questions in the field and highlight the potential impact of chemical tools for studying protein phosphatases.
9,9′‐Bifluorenylidene‐Core Perylene Diimide Acceptors for As‐Cast Non‐Fullerene Organic Solar Cells: The Isomeric Effect on Optoelectronic Properties
Authors: Zhao Yuan , Wang Huan , Xia Shengpeng , Zhou Feng , Luo Zhenghui , Luo Jiajia , He Feng , Yang Chuluo 
Published: January 2018

AbstractTwo different non‐fullerene small‐molecule acceptors, m‐PIB and p‐PIB, based on 9,9′‐bifluorenylidene (BF) and perylene diimide (PDI) were designed and synthesized. Four β‐substituted PDIs were linked to BF in different positions. Based on DFT analysis, derivative p‐PIB exhibited reduced intramolecular twisting between the PDI moieties, more delocalized wave function, and sufficiently wider π‐electron delocalization than that of m‐PIB. The absorption ability of p‐PIB was enhanced due to increased intermolecular interactions. By blending p‐PIB with poly{4,8‐bis[5‐(2ethylhexyl)thiophen‐2‐yl]benzo[1,2‐b:4,5‐b′]dithiophene‐co‐3‐fluorothieno[3,4‐b]‐thiophene‐2‐carboxylate} (PTB7‐Th), organic solar cells (OSCs) based on p‐PIB obtained a maximum power conversion efficiency of 5.95 % without any treatments. Due to the improved and balanced hole and electron mobilities, the short‐circuit current and fill factor of OSCs based on PTB7‐Th and p‐PIB were significantly increased. The AFM and TEM results revealed that the PTB7‐Th:p‐PIB film had favorable nanoscale phase separation and formed a bicontinuous interpenetrating network.
Organotin Dyes Bearing Anionic Boron Clusters as Cell‐Staining Fluorescent Probes
Authors: Muñoz‐Flores Blanca M. , Cabrera‐González Justo , Viñas Clara , Chávez‐Reyes Arturo , Dias H. V. Rasika , Jiménez‐Pérez Víctor M. , Núñez Rosario 
Published: January 2018

AbstractWithin the cell nucleus, in the nucleoli, ribosomal RNAs are synthesized and participate in several biological processes. To better understand nucleoli‐related processes, their visualization is often required, for which specific markers are needed. Herein, we report the design of novel fluorescent organotin compounds derived from 4‐hydroxy‐N′‐((2‐hydroxynaphthalen‐1‐yl)methylene)benzohydrazide and their cytoplasm and nucleoli staining of B16F10 cells in vitro. Tin compounds bearing an aliphatic carbon chain (‐C12H25) and an electron‐donating group (‐OH) were prepared, and the latter could be derivatized to bear the boron cluster anions [B12H12]2− and [3,3′‐Co(1,2‐C2B9H11)2]− (COSAN). All of the conjugates have been fully characterized and their luminescence properties have been assessed. In general, they show good quantum yields in solution (24–49 %), those for the COSAN derivatives being lower. Remarkably, the linking of [B12H12]2− and COSAN to the complexes made them more soluble, without being detrimental to their luminescence properties. Living B16F10 cells were treated with all of the compounds to determine their fluorescence staining properties; the compounds bearing the aliphatic chain showed a reduced staining capacity due to the formation of aggregates. Notably, the complexes bearing different boron clusters showed different staining effects; those bearing [B12H12]2− showed extraordinary staining of the nucleoli and cytoplasm, whereas those bearing COSAN were only detected in the cytoplasm. The remarkable fluorescence staining properties shown by these organotin compounds make them excellent candidates for fluorescence bioimaging in vitro.
A Combined Photochemical and Multicomponent Reaction Approach to Precision Oligomers
Authors: Konrad Waldemar , Bloesser Fabian R. , Wetzel Katharina S. , Boukis Andreas C. , Meier Michael A. R. , Barner‐Kowollik Christopher 
Published: January 2018

AbstractWe introduce the convergent synthesis of linear monodisperse sequence‐defined oligomers through a unique approach, combining the Passerini three‐component reaction (P‐3CR) and a Diels–Alder (DA) reaction based on photocaged dienes. A set of oligomers is prepared resting on a Passerini linker unit carrying an isocyano group for chain extension by P‐3CR and a maleimide moiety for photoenol conjugation enabling a modular approach for chain growth. Monodisperse oligomers are accessible in a stepwise fashion by switching between both reaction types. Employing sebacic acid as a core unit allows the synthesis of a library of symmetric sequence‐defined oligomers. The oligomers consist of alternating P‐3CR and photoblocks with molecular weights up to 3532.16 g mol−1, demonstrating the successful switching from P‐3CR to photoenol conjugation. In‐depth characterization was carried out including size‐exclusion chromatography (SEC), high‐resolution electrospray ionization mass spectrometry (ESI‐MS) and NMR spectroscopy, evidencing the monodisperse nature of the precision oligomers.
Fixing the Conformation of Calix[4]arenes: When Are Three Carbons Not Enough?
Authors: Matthews Susan E. , Cecioni Samy , O'Brien John E. , MacDonald Colin J. , Hughes David L. , Jones Garth A. , Ashworth Stephen H. , Vidal Sébastien 
Published: January 2018

AbstractCalix[4]arenes are unique macrocycles that through judicious functionalisation at the lower rim can be either fixed in one of four conformations or remain conformationally flexible. Introduction of propynyl or propenyl groups unexpectedly provides a new possibility; a unidirectional conformational switch, with the 1,3‐alternate and 1,2‐alternate conformers switching to the partial cone conformation, whilst the cone conformation is unchanged, under standard experimental conditions. Using 1H NMR kinetic studies, rates of switching have been shown to be dependent on the starting conformation, upper‐rim substituent, where reduction in bulk enables faster switching, solvent and temperature with 1,2‐alternate conformations switching fastest. Ab initio calculations (DFT) confirmed the relative stabilities of the conformations and point towards the partial cone conformer being the most stable of the four. The potential impact on synthesis through the “click” reaction has been investigated and found not to be significant.
Synthesis of Multifunctional Spirocyclic Azetidines and Their Application in Drug Discovery
Authors: Kirichok Alexander A. , Shton Irina O. , Pishel Irina M. , Zozulya Sergey A. , Borysko Petro O. , Kubyshkin Vladimir , Zaporozhets Olha A. , Tolmachev Andrei A. , Mykhailiuk Pavel K. 
Published: January 2018

AbstractThe synthesis of multifunctional spirocycles was achieved from common cyclic carboxylic acids (cyclobutane carboxylate, cyclopentane carboxylate, l‐proline, etc.). The whole sequence included only two chemical steps—synthesis of azetidinones, and reduction into azetidines. The obtained spirocyclic amino acids were incorporated into a structure of the known anesthetic drug Bupivacaine. The obtained analogues were more active and less toxic than the original drug. We believe that this discovery will lead to a wide use of spirocyclic building blocks in drug discovery in the near future.
Mechanochromic Polymers That Turn Green Upon the Dissociation of Diarylbibenzothiophenonyl: The Missing Piece toward Rainbow Mechanochromism
Authors: Ishizuki Kuniaki , Oka Hironori , Aoki Daisuke , Goseki Raita , Otsuka Hideyuki 
Published: January 2018

AbstractMechanochromic polymers, that is, polymers sensitive to mechanical impact, promise great potential for applications in damage sensors. In particular, radical‐type mechanochromic polymers, which produce colored radical species in response to mechanical stress, may enable not only the visualization of mechanical stress, but also its quantitative evaluation by electron paramagnetic resonance analysis. Herein, a radical‐type mechanochromic polymer that exhibits a color change from white to green upon dissociation of a diarylbibenzothiophenonyl moiety at the mid‐point of a polystyrene chain is presented, and its mechanochromic behavior is examined. Mechanochromic materials that show a variety of colors (“rainbow colors”) in response to mechanical stress were prepared by simply mixing radical‐type mechanochromic polymers of primary colors.