bluuebunny/crossref_metadata_2025 huggingface dataset:
Controlling Ferromagnetic Ground States and Solitons in Thin Films and Nanowires Built from Iron Phthalocyanine Chains
Authors: Wu Zhenlin , Robaschik Peter , Fleet Luke R. , Felton Solveig , Aeppli Gabriel , Heutz Sandrine
Published: May 2019

Iron phthalocyanine (FePc) is a molecular semiconductor whose building blocks are 1D ferromagnetic chains. It is shown that its optical and magnetic properties are controlled by the growth strategy, obtaining extremely high coercivities of over 1 T and modulating the exchange constant between 15 and 29 K through switching from thin films with controlled orientations, to ultralong nanowires. Magnetization measurements are analyzed using concepts and formulas with broad applicability to all 1D ferromagnetic chains. They show that FePc is best described by a xy model with moments preferentially lying in the molecular planes. The chain Hamiltonian is very similar to that for the classic inorganic magnet CsNiF3, but with ferromagnetic rather than antiferromagnetic interchain interactions. The dominant degrees of freedom are topological excitations called solitons, namely moving 1D magnetic domain walls, and at low temperatures and fields a “super‐Curie–Weiss” law characteristic of nearly 1D xy and Heisenberg ferromagnets, where susceptibility scales as 1/(T2–θ2), is observed. The ability to control the molecular orientation and ferromagnetism of FePc systems, and produce them on flexible substrates, together with excellent transistor characteristics reported previously for phthalocyanine analogues, makes them potentially useful for magneto‐optical and spintronic devices.
Layered Ruddlesden–Popper Efficient Perovskite Solar Cells with Controlled Quantum and Dielectric Confinement Introduced via Doping
Authors: Li Hao , Wang Xikui , Zhang Tao , Gong Xiu , Sun Qiang , Pan Han , Shen Yan , Ahmad Shahzada , Wang Mingkui
Published: May 2019

Layered Ruddlesden–Popper (RP) hybrid perovskite semiconductors have recently emerged as promising materials for photovoltaics application. However, the strong quantum and dielectric confinement of RP perovskite compounds increases their optical bandgap and binding energy of exciton, which limit their application in solar cells. Herein, the doping of RP‐based (BA)2(MA)3Pb4I13 perovskite materials by means of Li+ is reported for the first time, which can significantly help to reduce dielectric confinement and thus the exciton‐binding energy via reducing the dielectric constant difference between organic spacer cation and inorganic framework. Furthermore, the Li+ doping boosts the carrier mobility, reduces the trap density states, and thus allows to achieve power conversion efficiency of ≈15% via Li+‐(BA)2(MA)3Pb4I13‐based perovskite solar cell, which is the highest efficiency for layered perovskites (n = 4) so far. This work highlights the promising ionic doping engineering for further improvement of the layered perovskite materials.
Impact of Dispersity and Hydrogen Bonding on the Lubricity of Poly(acrylamide) Brushes
Authors: Mandal Joydeb , Simic Rok , Spencer Nicholas D.
Published: May 2019

The effects of chain‐length dispersity and monomer type on the lubricity of acrylamide‐based polymer brushes have been examined in aqueous media. The polymer brushes used have been synthesized by surface‐initiated, atom‐transfer radical polymerization of N,N‐dimethylacrylamide (DMAM), N‐hydroxyethyl acrylamide (HEAM), and N‐isopropylacrylamide. Polymerization reactions have been performed in the presence and also in the absence of CuX2 and tEtAmX (X = Cl or Br), in order to achieve polymer brushes with substantial differences in their chain‐length dispersities. While an influence of the dispersity on the lubricity of the polymer brushes can be observed, it is convoluted with the competing phenomena of hydrogen bonding and increased water content. The most hydrophilic, p(HEAM) brush exhibits the highest friction coefficient (μ) of ≈0.04 compared to ≈0.004 in the case of the p(DMAM) brush. Such a large difference is presumed to originate from the hydrogen bonding between the tribological countersurface (plasma‐oxidized poly(dimethylsiloxane)) and the p(HEAM) chains, as evidenced by the substantial reduction in μ when the friction measurements are performed in 5 m urea solution instead of pure milli‐Q water.
Sea Urchin‐Like MOF‐Derived Formation of Porous Cu3P@C as an Efficient and Stable Electrocatalyst for Oxygen Evolution and Hydrogen Evolution Reactions
Authors: Rong Jian , Xu Jinchao , Qiu Fengxian , Zhu Yao , Fang Yuanyuan , Xu Jicheng , Zhang Tao
Published: May 2019

Owning to the energy crisis and environmental pollution, it is urgent to develop an efficient and earth‐abundant electrocatalyst for water splitting. In this work, the Cu2O cubes are first synthesized through a modified precipitation method, and it is subsequently selected as the Cu2+ source to synthesize 3D MOF (metal‐organic framework, Cu‐BDC) nanoarray by a facile and efficient bottom‐up method. Next, porous Cu3P@C is prepared via the low‐temperature phosphorization of 3D Cu‐BDC nanoarray as a high‐performance electrocatalyst for oxygen and hydrogen evolution reactions (OER and HER). In particular, the effect of reaction temperature on the morphology of 3D Cu‐BDC precursor is studied in detail. Experimental results reveal that Cu3P@C‐120 derived from sea urchin‐like Cu‐BDC exhibits excellent electrocatalytic performance owning to the high special surface area, developed porous structure, and the uniform dispersion of Cu3P nanoparticles, which affords the current density of 10 mA cm−2 at low overpotentials of 300 and 124 mV for OER (alkaline medium) and HER (acidic medium) with Tafel slopes of 24 and 29 mV dec−1, respectively. Remarkably, Cu3P@C‐120 also exhibits an excellent durability for OER and HER, making it an efficient bifunctional electrocatalyst for application in the production of clean hydrogen fuel.
Recent Development of Ni/Fe‐Based Micro/Nanostructures toward Photo/Electrochemical Water Oxidation
Authors: Gao Rui , Yan Dongpeng
Published: May 2019

The oxygen evolution reaction (OER), as an important process involved in water splitting and rechargeable metal–air batteries, has drawn increasing attention in the context of clean energy generation and efficient energy storage. This review concerns the progress and new discoveries in the field of Ni/Fe‐based micro/nanostructures toward electrochemical and photo‐electrochemical (PEC) water oxidation during last few years. First, toward the design and construction of new electrocatalysis, different types of current Ni/Fe‐based compounds for OER are summarized. The mechanism studies of the active phases and positions of Ni/Fe‐based micro/nanostructures are further introduced to understand the properties of catalytic active sites, which could facilitate further improving the performance of Ni/Fe‐based OER electrocatalysts. Second, splitting water using sunlight with low overpotential is another important target in making solar‐to‐hydrogen micro/nanodevices, and thus attention is then focused on the development of several important Ni/Fe‐based PEC catalysts. Third, the recent theoretical calculations on the OER mechanism during water splitting and insights into electronic structures are analyzed; finally, the future trends and perspectives are also discussed briefly.
High‐Performance and Stable Perovskite Solar Cells Based on Dopant‐Free Arylamine‐Substituted Copper(II) Phthalocyanine Hole‐Transporting Materials
Authors: Feng Yaomiao , Hu Qikun , Rezaee Ehsan , Li Minzhang , Xu Zong‐Xiang , Lorenzoni Andrea , Mercuri Francesco , Muccini Michele
Published: May 2019

A power conversion efficiency (PCE) as high as 19.7% is achieved using a novel, low‐cost, dopant‐free hole transport material (HTM) in mixed‐ion solution‐processed perovskite solar cells (PSCs). Following a rational molecular design strategy, arylamine‐substituted copper(II) phthalocyanine (CuPc) derivatives are selected as HTMs, reaching the highest PCE ever reported for PSCs employing dopant‐free HTMs. The intrinsic thermal and chemical properties of dopant‐free CuPcs result in PSCs with a long‐term stability outperforming that of the benchmark doped 2,2′,7,7′‐Tetrakis‐(N,N‐di‐p‐methoxyphenylamine)‐9,9′‐Spirobifluorene (Spiro‐OMeTAD)‐based devices. The combination of molecular modeling, synthesis, and full experimental characterization sheds light on the nanostructure and molecular aggregation of arylamine‐substituted CuPc compounds, providing a link between molecular structure and device properties. These results reveal the potential of engineering CuPc derivatives as dopant‐free HTMs to fabricate cost‐effective and highly efficient PSCs with long‐term stability, and pave the way to their commercial‐scale manufacturing. More generally, this case demonstrates how an integrated approach based on rational design and computational modeling can guide and anticipate the synthesis of new classes of materials to achieve specific functions in complex device structures.
Herbivore resistance in congeneric and sympatric Nothofagus species is not related to leaf habit
Authors: Piper Frida I. , Gundale Michael J. , Fuenzalida Tomás , Fajardo Alex
Published: May 2019

Premise

Two fundamental hypotheses on herbivore resistance and leaf habit are the resource availability hypothesis (RAH) and the carbon–nutrient balance hypothesis (CNBH). The RAH predicts higher constitutive resistance by evergreens, and the CNBH predicts higher induced resistance by deciduous species. Although support for these hypotheses is mixed, they have rarely been examined in congeneric species.

Methods

We compared leaf constitutive and induced resistance (as leaf polyphenol and tannin concentrations, and as damage level in non‐choice experiments) and leaf traits associated with herbivory of coexisting Nothofagus species using (1) a defoliation experiment and (2) natural defoliation caused by an outbreak of a common defoliator of Nothofagus species.

Results

In the defoliation experiment, polyphenol and tannin concentrations were similar between deciduous and evergreen species; regardless of leaf habit, polyphenols increased in response to defoliation. In the natural defoliation survey, N. pumilio (deciduous) had significantly higher herbivory, lower carbon/nitrogen ratio and leaf mass per area, and higher nitrogen and phosphorus concentrations than N. betuloides (evergreen); N. antarctica (deciduous) had intermediate values. Polyphenol concentrations and herbivore resistance indicated by the non‐choice experiment were lower in N. pumilio than in N. antarctica and N. betuloides, which had similar values.

Conclusions

Higher herbivory in N. pumilio was associated with a higher nutritional value and a lower level of leaf carbon‐based defenses compared to both the evergreen and the other deciduous species, indicating that herbivore resistance in Nothofagus species cannot be attributed to only leaf habit as predicted by the RAH or CNBH.
Gold‐Catalyzed Bicyclic Annulations of 2‐Alkynylbenzaldehydes with Vinyldiazo Carbonyls that Serve as Five‐atom Building Units
Authors: Raj Antony Sekar Kulandai , Liu Rai‐Shung
Published: May 2019

This work reports gold‐catalyzed bicyclic annulations of 2‐alkynyl‐1‐carbonylbenzenes with vinyldiazo ketones that serve as five‐atom building units. The importance of these reactions is to access 4,5‐dihydro‐benzo[g]indazoles, which form the structural cores of various bioactive molecules. According to our mechanistic analysis, we postulate initial [5+4]‐cycloadditions between benzopyrilium intermediates and vinyldiazo ketones, followed by 6‐π‐electrocyclizations to achieve the excellent stereoselectivity.
A Regio‐ and Stereodivergent Synthesis of Homoallylic Amines by a One‐Pot Cooperative‐Catalysis‐Based Allylic Alkylation/Hofmann Rearrangement Strategy
Authors: Pearson Colin M. , Fyfe James W. B. , Snaddon Thomas N.
Published: May 2019

Herein, we report a modular synthetic route to linear and branched homoallylic amines that operates through a sequential one‐pot Lewis base/transition‐metal catalyzed allylic alkylation/Hofmann rearrangement strategy. This protocol is operationally trivial, proceeds from simple and easily prepared substrates and catalysts, and enables all aspects of regio‐ and stereoselectivity to be controlled through a conserved experimental protocol. Overall, the high levels of enantio‐, regio‐, and diastereoselectivity obtained, in concert with the ability to access orthogonally protected or free amines, render this a straightforward and effective approach for the preparation of useful enantioenriched homoallylic amines. We have also demonstrated the utility of the products in the context of pharmaceutical synthesis.
Low‐Temperature Growth of Carbon Nanotubes Catalyzed by Sodium‐Based Ingredients
Authors: Li Richard , Antunes Erica F. , Kalfon‐Cohen Estelle , Kudo Akira , Acauan Luiz , Yang Wei‐Chang D. , Wang Canhui , Cui Kehang , Liotta Andrew H. , Rajan Ananth Govind , Gardener Jules , Bell David C. , Strano Michael S. , Liddle J. Alexander , Sharma Renu , Wardle Brian L.
Published: May 2019

Synthesis of low‐dimensional carbon nanomaterials such as carbon nanotubes (CNTs) is a key driver for achieving advances in energy storage, computing, and multifunctional composites, among other applications. Here, we report high‐yield thermal chemical vapor deposition (CVD) synthesis of CNTs catalyzed by reagent‐grade common sodium‐containing compounds, including NaCl, NaHCO3, Na2CO3, and NaOH, found in table salt, baking soda, and detergents, respectively. Coupled with an oxidative dehydrogenation reaction to crack acetylene at reduced temperatures, Na‐based nanoparticles have been observed to catalyze CNT growth at temperatures below 400 °C. Ex situ and in situ transmission electron microscopy (TEM) reveal unique CNT morphologies and growth characteristics, including a vaporizing Na catalyst phenomenon that we leverage to create CNTs without residual catalyst particles for applications that require metal‐free CNTs. Na is shown to synthesize CNTs on numerous substrates, and as the first alkali group metal catalyst demonstrated for CNT growth, holds great promise for expanding the understanding of nanocarbon synthesis.
Direct Prebiotic Pathway to DNA Nucleosides
Authors: Teichert Jennifer S. , Kruse Florian M. , Trapp Oliver
Published: May 2019

It is assumed that RNA played a key role in the origin of life, and the transition to more complex but more stable DNA for continuous information storage and replication requires the development of a ribonucleotide reductase to obtain the deoxyribonucleotides from ribonucleotides. This step, as well as an alternative path from abiotic molecules to DNA‐based life is completely unknown. Shown here is the formation of deoxyribonucleosides under relevant prebiotic conditions in water in high regio‐ and stereoselectivity, from all canonical purine and pyrimidine bases, by condensation with acetaldehyde and sugar‐forming precursors. Thus, a continuous path to deoxyribonucleosides, starting from simple, prebiotically available molecules has been discovered. Furthermore, the deoxyapionucleosides (DApiNA) were identified as a potential DNA progenitor. The results suggest that the DNA world evolved much earlier than previously assumed.
Novel 13C‐detected NMR Experiments for the Precise Detection of RNA Structure
Authors: Schnieders Robbin , Wolter Antje C. , Richter Christian , Wöhnert Jens , Schwalbe Harald , Fürtig Boris
Published: May 2019

Up to now, NMR spectroscopic investigations of RNA have utilized imino proton resonances as reporters for base pairing and RNA structure. The nucleobase amino groups are often neglected, since most of their resonances are broadened beyond detection due to rotational motion around the C–NH2 bond. Here, we present 13C‐detected NMR experiments for the characterization of all RNA amino groups irrespective of their motional behavior. We have developed a C(N)H‐HDQC experiment that enables the observation of a complete set of sharp amino resonances through the detection of proton‐NH2 double quantum coherences. Further, we present an “amino”‐NOESY experiment to detect NOEs to amino protons, which are undetectable by any other conventional NOESY experiment. Together, these experiments allow the exploration of additional chemical shift information and inter‐residual proton distances important for high‐resolution RNA secondary and tertiary structure determination.
Output feedback control of a three‐phase four‐wire unified power quality conditioner
Authors: Benazza Bouchaib , Ouadi Hamid , Giri Fouad
Published: May 2019

The increasing penetration of power electronics in electrical equipment entails a significant impact on the deterioration of power supply quality. In this paper, the problem of power quality is addressed for distorted three‐phase four‐wire power grids supplying non‐linear unbalanced loads. A unified power quality conditioner (UPQC) is considered to ensure satisfactory electrical energy quality. To this end, a UPQC controller is designed to meet four control objectives: i) compensation of the harmonics and the reactive load currents; ii) compensation for the harmonic voltages at the point of common coupling (PCC); iii) cancelation of the neutral current; iv) and regulation of the inverter DC voltage. The control design relies on the UPQC nonlinear model that accounts for the electrical grid line impedance. Unlike previous works, the proposed controller features an output‐feedback nature as it combines a nonlinear regulator, designed with a sliding‐mode technique, and a state observer designed using a Lyapunov stability based technique. The latter provides the former with online estimates of the series filter AC voltages, which are not assumed to be accessible to measurements. The closed loop error system is analyzed using the average stability approach. It turns out that all (tracking and estimation) errors are asymptotically vanishing, except for the DC bus voltage tracking error, which is periodic in steady‐state with an amplitude depending on the (DC bus) capacitor, the larger the capacitor the smaller the steady‐state DC voltage tracking error level. This theoretical result is confirmed by simulations involving wide range variations of the load current.
Development of tissue‐engineered skeletal muscle manufacturing variables
Authors: Wragg Nicholas M. , Player Darren J. , Martin Neil R. W. , Liu Yang , Lewis Mark P.
Published: May 2019

Three‐dimensional tissue‐engineered structures enable more representative determination of novel drug or material effects on tissue than traditional monolayer cell cultures. This study sought to better understand how key manufacturing variables affect the myotube characteristics of a skeletal muscle model toward reducing resource use and to develop an understanding of scaling on model consistency. C2C12 murine myoblasts were seeded in a tethered collagen scaffold from which directional myotubes form in response to lines of tension and a change in medium. Collagen polymerizing area length‐to‐width ratios greater than one were found to reduced cell–matrix attachment and remodeling forces significantly (p < .05) correlating to a reduction in cell fusion potential. Following this, utilizing a factorial design of experiment, 4 million C2C12s/ml, with a polymerizing area width 150% of the anchor point, produced the most favorable myotube characteristics and dramatically reduced the incidence of rupture. Scaled constructs showed no significant differences when compared to larger models. Approximately 20 myotubes with a variation in the alignment of <25° in the central region were consistently observed in the final models. This demonstrates the influence of initial manufacturing variables on tissue formation and has produced a benchmark model for consistent production across scaled constructs for future optimization and as a potential cost‐effective preclinical testbed.
Micropatterned substrates with physiological stiffness promote cell maturation and Pompe disease phenotype in human induced pluripotent stem cell‐derived skeletal myocytes
Authors: Jiwlawat Nunnapas , Lynch Eileen M. , Napiwocki Brett N. , Stempien Alana , Ashton Randolph S. , Kamp Timothy J. , Crone Wendy C. , Suzuki Masatoshi
Published: May 2019

Recent advances in bioengineering have enabled cell culture systems that more closely mimic the native cellular environment. Here, we demonstrated that human induced pluripotent stem cell (iPSC)‐derived myogenic progenitors formed highly‐aligned myotubes and contracted when seeded on two‐dimensional micropatterned platforms. The differentiated cells showed clear nuclear alignment and formed elongated myotubes dependent on the width of the micropatterned lanes. Topographical cues from micropatterning and physiological substrate stiffness improved the formation of well‐aligned and multinucleated myotubes similar to myofibers. These aligned myotubes exhibited spontaneous contractions specifically along the long axis of the pattern. Notably, the micropatterned platforms developed bundle‐like myotubes using patient‐derived iPSCs with a background of Pompe disease (glycogen storage disease type II) and even enhanced the disease phenotype as shown through the specific pathology of abnormal lysosome accumulations. A highly‐aligned formation of matured myotubes holds great potential in further understanding the process of human muscle development, as well as advancing in vitro pharmacological studies for skeletal muscle diseases.
Sustainable development: The effects of environmental policy disclosure in advertising
Authors: Chang Hsiu‐Hua , Tsai Shin‐Hua , Huang Chun‐Chen
Published: May 2019

Sustainable development is a key issue for society. Beside corporate's efforts, consumers should have responsibilities for environmental protection and consider sustainable coexistences between future generations and natural ecosystems. In this study, a 4 × 2 factorial between‐subject experiment is adopted to develop eight environmental policy disclosure scenarios based on different environmental advertising claims (product orientation, process orientation, image orientation, and environmental fact) and eco‐labels (available/unavailable) to explore the effect of consumer attitudes and behaviors. This study's results show that environmental advertising claims have significant effects on consumers' attitudes. The product, process, and image orientation advertising, along with advertising with eco‐labels, can induce more positive attitudes and stronger purchase intentions. Individuals with greater environmental concerns have a significant positive attitude toward environmental advertising. Consumer attitudes toward environmental advertising also have positive effects on purchase intentions and sustainable consumption behaviors. Finally, this study offers useful findings, practical implications, and insights.
Economic evaluation of the development of a phage therapy product for the control of Salmonella in poultry
Authors: Torres‐Acosta Mario A. , Clavijo Viviana , Vaglio Christopher , González‐Barrios Andrés F. , Vives‐Flórez Martha J. , Rito‐Palomares Marco
Published: May 2019

Poultry products are one of the major transmission media of Salmonella enteritidis to humans. A promising alternative to reduce the load of Salmonella in poultry are bacteriophages. Elsewhere, a mixture of six bacteriophages has been used successfully, but large‐scale production would be necessary to supply potential poultry market and costs analyses have not been calculated yet. For this, a powerful tool to predict production costs is bioprocess modeling coupled with economic analyses. This work aims to model the scaled‐up production of a six bacteriophages mixture based on a laboratory/pilot‐scale production using Biosolve Process. For the model construction, a combination of experimental and reported data was applied, in which different production alternatives and the range of 1–100% of the Colombian poultry market (at broiler's farm and slaughterhouse) were analyzed. Results indicate that the best cost‐effective process configuration/scale is to use one bioreactor (156 L) for the six bacteriophages, then a 0.45 μm filtration for removal of biomass, and a 0.22 μm filtration for sterility; this to supply the 35% of the market size for broiler farms (equivalent to 210 million chickens). This configuration gives a production cost per chicken of US$ 0.02. Additionally, a sensitivity analysis and a theoretical contrast for understanding the impact that titer and recovery have on production scale determined that titer affects the most the cost and requires optimization. The present works serves as a first, and required, approach for the development of phage therapy products that are alternatives to present‐day pathogens control strategies.
Multitask learning on monocular water images: Surface reconstruction and image synthesis
Authors: Xie Xueguang , Zhai Xiao , Hou Fei , Hao Aimin , Qin Hong
Published: May 2019

In this paper, we present a new strategy, a joint deep learning architecture, for two classic tasks in computer graphics: water surface reconstruction and water image synthesis. Modeling water surfaces from single images can be regarded as the inverse of image rendering, which converts surface geometries into photorealistic images. On the basis of this fact, we therefore consider these two problems as a cycle image‐to‐image translation and propose to tackle them together using a pair of neural networks, with the three‐dimensional surface geometries being represented as two‐dimensional surface normal maps. Furthermore, we also estimate the imaging parameters from the existing water images with a subnetwork to reuse the lighting conditions when synthesizing new images. Experiments demonstrate that our method achieves an accurate reconstruction of surfaces from monocular images efficiently and produces visually plausible new images under variable lighting conditions.
Intravascular modality‐guided versus angiography‐guided percutaneous coronary intervention in acute myocardial infarction
Authors: Kim Namkyun , Lee Jang Hoon , Jang Se Yong , Bae Myung Hwan , Yang Dong Heon , Park Hun Sik , Cho Yongkeun , Jeong Myung Ho , Park Jong‐Seon , Kim Hyo‐Soo , Hur Seung‐Ho , Seong In‐Whan , Cho Myeong‐Chan , Kim Chong‐Jin , Chae Shung Chull ,   for the Korea Acute Myocardial Infarction Registry ‐ National Institute of Health Investigators
Published: May 2019

Background

Few data are available for current usage patterns of intravascular modalities such as intravascular ultrasound (IVUS), optical coherence tomography (OCT), and fractional flow reserve (FFR) in acute myocardial infarction (AMI). Moreover, patient and procedural‐based outcomes related to intravascular modality guidance compared to angiography guidance have not been fully investigated yet.

Methods

We examined 11,731 patients who underwent percutaneous coronary intervention (PCI) from the Korea AMI Registry–National Institute of Health database. Patient‐oriented composite endpoint (POCE) was defined as all‐cause death, any infarction, and any revascularization. Device‐oriented composite endpoint (DOCE) was defined as cardiac death, target‐vessel reinfarction, and target‐lesion revascularization.

Results

Overall, intravascular modalities were utilized in 2,659 (22.7%) patients including 2,333 (19.9%) IVUS, 277 (2.4%) OCT, and 157 (1.3%) FFR. In the unmatched cohort, POCE (5.4 vs. 8.5%; adjusted hazard ratio (HR) 0.75; 95% confidence interval (CI) 0.61–0.93; p = .008) and DOCE (4.6 vs. 7.4%; adjusted HR 0.77; 95% CI 0.61–0.97; p = .028) were significantly lower in intravascular modality‐guided PCI compared with angiography‐guided PCI. In the propensity‐score‐matched cohorts, POCE (5.9 vs. 7.7%; HR 0.74; 95% CI 0.60–0.92; p = .006) and DOCE (5.0 vs. 6.8%; HR 0.72; 95% CI 0.57–0.90; p = .004) were significantly lower in intravascular modality guidance compared with angiography guidance. The difference was mainly driven by reduced all‐cause mortality (4.4 vs. 7.0%; p < .001) and cardiac mortality (3.3 vs. 5.2%; p < .001).

Conclusion

In this large‐scale AMI registry, intravascular modality guidance was associated with an improving clinical outcome in selected high‐risk patients.
Long‐term transesophageal echocardiography after patent foramen ovale closure by BioSTAR and Amplatzer patent foramen ovale occluders
Authors: Suligoj Natasa Cernic , Rojko Maja , Suligoj Brina , Zorc Metka , Kar Saibal , Noc Marko
Published: May 2019

Objectives

To compare transesophageal echocardiography (TOE) findings after patent foramen ovale (PFO) closure by BioSTAR (NMT Medical Inc, Boston, MA) and Amplatzer PFO occluders (Abbott Vascular, Plymouth, MN).

Background

PFO closure with a biodegradable device represents an attractive alternative to permanent devices. Long‐term effectiveness and morphology after biodegradation remain unknown.

Methods

Between February 2008 and June 2014, 49 patients received BioSTAR and 48 Amplatzer PFO occluder. TOE was performed after closure, at 6 months and beyond 2 years.

Results

PFO features were comparable between the groups. Immediate effective closure (<5 bubbles on Valsalva) was obtained in 96% by BioSTAR and 88% by Amplatzer PFO occluder (p = .16). Except for transient fever after BioSTAR (10.8 vs. 0%; p = .08), there was no adverse events. TOE at 6 months revealed comparable effective closure (93 vs. 89%; p = .74), all devices in correct position and no thrombus/pericardial effusion. In the BioSTAR group, a peri‐device left‐to‐right color Doppler shunt was documented in one patient (2.2%), protrusion of the nitinol framework strut(s) into the atrial cavity in two patients (4.3%), and both events in one patient (2.2%). TOE beyond 2 years showed comparable effective closure (92 vs. 96%; p = 1.00) and again BioSTAR‐associated peri‐device left‐to‐right shunt and metal framework strut(s) protrusion. There was no stroke or peripheral embolization in either group while TIA was numerically greater in BioSTAR patients (6.8 vs. 2.5%; p = .61).

Conclusion

BioSTAR provided similar PFO closure rate as Amplatzer PFO occluder. As yet unreported BioSTAR‐associated peri‐device left‐to‐right shunt and metal framework strut(s) protrusion may have practical implications for further development of biodegradable devices.
Copper‐Catalyzed Tandem C−H/N−H Activation, Cyclization[4+2] and Dehydration of Arylamides with Formamide: Synthesis of 4(3H)‐Quinazolinones Derivatives
Authors: Sun Jian , Wang Guodong , Hao Liqiang , Han Junfen , Li Hongshuang , Duan Guiyun , You Guirong , Li Furong , Xia Chengcai
Published: May 2019

A novel route for copper‐catalyzed tandem C−H/N−H activation, cyclization[4+2] and dehydration of arylamides with formamide to synthesize 4(3H)‐quinazolinone derivatives was developed. This approach is assisted by an 8‐aminoquinoline group and the formamide provide the nitrogen and carbon source. This reaction is compatible with various functional groups, and the reaction conditions are mild. In addition, it uses cheaply and commercially available reagents, and provides direct access to 4(3H)‐quinazolinones.
Effect of Ca Promoter on the Structure and Catalytic Behavior of FeK/Al2O3 Catalyst in Fischer‐Tropsch Synthesis
Authors: Wang Hongyu , Huang Shouying , Wang Jian , Zhao Qiao , Wang Yifei , Wang Yue , Ma Xinbin
Published: May 2019

Fischer‐Tropsch synthesis (FTS) to olefins is an alternative route for lower olefins production. The role of alkaline‐earth metals as promoters in FTS was not so clear. Herein, we prepared a series of FeKCa/Al2O3 catalysts by excessive co‐impregnation method to elucidate the promotion effect of Ca on catalytic performance. Characterization technologies of N2 physisorption, XRD, Raman spectrum, TEM and CO chemisorption were used to study the textural properties, phase composition and dispersion of Fe species. The results showed that the addition of Ca promotes dispersion of iron species thus leads to much smaller crystallite size. Meanwhile, no electron donation effect was observed upon Ca introduction, as evidenced by XPS and H2‐TPR. A maximum of FTY is achieved at 1.0 wt.% Ca, followed by a decline when adding excessive Ca due to less exposed active sites. Notably, the product distribution is almost unchanged. The nearly constant TOF values with and without Ca addition indicates Ca works only as a structural promoter rather than chemical promoter.
On‐the‐fly Catalyst Modification: Strategy to Improve Catalytic Processes Selectivity and Understanding
Authors: Sá Jacinto , Medlin J. Will
Published: May 2019

Hydrogenation is a quintessential process to the chemical industry. It is heavily involved in organic synthesis and fuel production, among other processes. Preferentially the reactions are carried out with heterogeneous catalysts and when possible in flow mode. Herein, we provide a retrospective on selective surface modification of catalysts for improved selectivity and understanding of catalytic reactivity. In addition, we provide a prospectus for an emerging strategy of carrying out surface modification on‐the‐fly to produce novel catalysts in a fast and reproducible way and to understand catalytic phenomena.
Selective Depolymerisation of γ‐Oxidised Lignin via NHC Catalysed Redox Esterification
Authors: Xiao Ganyuan , Lancefield Christopher S. , Westwood Nicholas J.
Published: May 2019

The development of new catalytic methods for the processing of lignocellulose‐derived renewable feedstocks continues to gain momentum, despite the considerable challenges associated with the use of complex biopolymers such as lignin. Here, we report a new two‐step depolymerisation method for lignin involving primary alcohol oxidation followed by a NHC‐mediated redox esterification‐depolymerisation step. The process takes advantage of the inherent structure of the β‐aryl ether units present in the specific type of lignin that was used (butanosolv) and delivers 4 novel aromatic monomers which retain the C3 side chain present in the lignin subunits. The utility of the major product is assessed suggesting that rapid access to a wide range of interesting chemical could be achieved from this renewable building block.
A Scandium Metalloligand‐Based Heterobimetallic Pd−Sc Complex: Electronic Tuning Through a Very Short Pd→Sc Dative Bond
Authors: Du Jun , Huang Zeming , Zhang Yanan , Wang Shaowu , Zhou Shuangliu , Fang Huayi , Cui Peng
Published: May 2019

The first heterobimetallic Pd−Sc complex featuring a very short Pd→Sc dative bond has been synthesized and characterized by multinuclear NMR spectroscopy, X‐ray diffraction analysis, and electrochemistry. Computational studies elucidated the nature of the Pd→Sc bond as a donor–acceptor interaction, which generates a more electron‐deficient Pd0 metal center as compared to that in the mono Pd0 complex in their reactions with isonitrile and carbon monoxide. Cooperative reactivity has been demonstrated in the reaction with MeI.
Silicate‐Phenolic Networks: Coordination‐Mediated Deposition of Bioinspired Tannic Acid Coatings
Authors: Weber Florian , Liao Wei‐Chih , Barrantes Alejandro , Edén Mattias , Tiainen Hanna
Published: May 2019

Surface modification with polyphenolic molecules has been pursued in biomedical materials owing to their antioxidant, anti‐inflammatory, and antimicrobial characteristics. Recently, the use of silicic acid (Siaq) as a mediator for efficient surface deposition of tannic acid (TA) was reported, but the postulated Si‐TA polymeric networks were not characterized. Herein, we present unambiguous evidence for silicate‐TA networks that involve Si−O−C motifs by using solid‐state NMR spectroscopy, further supported by XPS and ToF‐SIMS. By using QCM‐D we demonstrate the advantages of Siaq, compared to using transition‐metal ions, to improve the coating efficiency under mildly acidic conditions. The presented homogenous coating buildup and validated applicability in inorganic buffers broadens the use of TA for surface modifications in technological and biomedical applications.
Non‐linear absorption of an intense laser pulse propagating in wiggler‐assisted underdense collisional plasma
Authors: Abedi‐Varaki Mehdi , Panahi Nasser
Published: May 2019

In this article, the propagation of an intense laser pulse through underdense collisional plasma in the presence of planar magnetostatic wiggler is studied. It is shown that the electron density distribution, in the presence of planar wiggler with increasing of the normalized plasma length, increases initially and then reaches a peak for different values of wiggler amplitudes. In addition, it is found that the existence of wiggler field leads to an increase in the electron density distribution and subsequently enhancement of electric field. Moreover, it is observed that by increasing the wiggler field, as a result of the increase of the electron density distribution, the dielectric permittivity constant is reduced. It is seen that while wiggler magnetic field was applied appropriately, the total absorption coefficient in the underdense collisional isothermal magnetized plasma improves. In fact, increase of wiggler magnetic field causes the enhancement of the total absorption coefficient of plasma medium.
Environmental factors affect the distribution of two Epichloë fungal endophyte species inhabiting a common host grove bluegrass (Poa alsodes)
Authors: Shymanovich Tatsiana , Faeth Stanley H.
Published: May 2019

Aim

The endophyte Epichloë alsodes, with known insecticidal properties, is found in a majority of Poa alsodes populations across a latitudinal gradient from North Carolina to New York. A second endophyte, E. schardlii var. pennsylvanica, with known insect‐deterring effects, is limited to a few populations in Pennsylvania. We explored whether such disparate differences in distributions could be explained by selection from biotic and abiotic environmental factors.

Location

Along the Appalachian Mountains from North Carolina to New York, USA.

Taxon

Fungi.

Methods

Studied correlations of infection frequencies with abiotic and biotic environmental factors. Checked endophyte vertical transmission rates and effects on overwintering survival. With artificial inoculations for two host populations with two isolates per endophyte species, tested endophyte–host compatibility. Studied effects of isolates on host performances in greenhouse experiment with four water‐nutrients treatments.

Results

Correlation analysis revealed positive associations of E. alsodes frequency with July Max temperatures, July precipitation, and soil nitrogen and phosphorous and negative associations with insect damage and soil magnesium and potassium. Plants infected with E. alsodes had increased overwintering survival compared to plants infected with E. schardlii or uninfected (E−) plants. Artificial inoculations indicated that E. alsodes had better compatibility with a variety of host genotypes than did E. schardlii. The experiment with reciprocally inoculated plants grown under different treatments revealed a complexity of interactions among hosts, endophyte species, isolate within species, host plant origin, and environmental factors. Neither of the endophyte species increased plant biomass, but some of the isolates within each species had other effects on plant growth such as increased root:shoot ratio, number of tillers, and changes in plant height that might affect host fitness.

Main conclusion

In the absence of clear and consistent effects of the endophytes on host growth, the differences in endophyte‐mediated protection against herbivores may be the key factor determining distribution differences of the two endophyte species.
Macroevolution of arboreality in salamanders
Authors: Baken Erica K. , Adams Dean C.
Published: May 2019

Evolutionary theory predicts that selection in distinct microhabitats generates correlations between morphological and ecological traits, and may increase both phenotypic and taxonomic diversity. However, some microhabitats exert unique selective pressures that act as a restraining force on macroevolutionary patterns of diversification. In this study, we use phylogenetic comparative methods to investigate the evolutionary outcomes of inhabiting the arboreal microhabitat in salamanders. We find that arboreality has independently evolved at least five times in Caudata and has arisen primarily from terrestrial ancestors. However, the rate of transition from arboreality back to terrestriality is 24 times higher than the converse. This suggests that macroevolutionary trends in microhabitat use tend toward terrestriality over arboreality, which influences the extent to which use of the arboreal microhabitat proliferates. Morphologically, we find no evidence for an arboreal phenotype in overall body proportions or in foot shape, as variation in both traits overlaps broadly with species that utilize different microhabitats. However, both body shape and foot shape display reduced rates of phenotypic evolution in arboreal taxa, and evidence of morphological convergence among arboreal lineages is observed. Taken together, these patterns suggest that arboreality has played a unique role in the evolution of this family, providing neither an evolutionary opportunity, nor an evolutionary dead end.
Transient stability monitoring and preventive control based on CCT distribution factor
Authors: Nakamura Yuki , Yorino Naoto , Sasaki Yutaka , Zoka Yoshifumi
Published: May 2019

This paper proposes a monitoring and control method for transient stability (TS). First, it is clarified that there may exist various critical patterns of uncertain power flows causing instability due to photovoltaic generations. Then, the use of critical clearing time (CCT) is suggested as a TS index, which can be computed by conventional TS analysis tools. A distribution factor (DF) for controlling CCT is investigated, referred to as CCT‐DF in this paper. Then, three optimization problems using CCT‐DF are formulated based on bilevel optimization to obtain reliable operation planning. The combined use of the optimizations guarantees the power system robust security under uncertainties.
Synthesis and Reactivity of Tris(pentafluoroethyl)gallium Compounds
Authors: Niemann Mark , Neumann Beate , Stammler Hans‐Georg , Hoge Berthold
Published: May 2019

The reaction of [GaCl3(OEt2)n] with LiC2F5 surprisingly leads to the formation of the anion [Ga(C2F5)3Cl]–. The obtained lithium and tetraphenylphosphonium salts are useful starting materials for new pentafluoroethylgallium compounds. [PPh4][Ga(C2F5)3Cl] was conveniently transformed into [PPh4][Ga(C2F5)3X] (X = F, Br, I) with HF, NaBr, and NaI. Treatment of [Li(OEt2)n][Ga(C2F5)3Cl] with aqueous hydrogen chloride gives rise to the tris(pentafluoroethyl)gallane adduct [Ga(C2F5)3{(OH2)(OEt2)}]. Thermolysis of [Li(OEt2)n][Ga(C2F5)3Cl] affords another tris(pentafluoroethyl)gallane adduct, [Ga(C2F5)3(OEt2)], which can be converted into [Ga(C2F5)3(dmap)] (dmap = 4‐dimethylaminopyridine). [Ga(C2F5)3(OEt2)] as well as [Ga(C2F5)3(dmap)] react with [PPh4]Cl to [PPh4][Ga(C2F5)3Cl] and with HF to [HDMAP][Ga(C2F5)3F]. Both [Ga(C2F5)3(OEt2)] and [Ga(C2F5)3(dmap)] are precursors for the previously reported weakly coordinating anion [Ga(C2F5)4]–. Characterizations of the new compounds were carried out by NMR and IR spectroscopy, mass spectrometry, X‐ray diffraction and elemental analyses.
Technical and economic evaluation of separation of dimethyl disulfide from disulfide oil at liquefied petroleum gas treatment facilities of Assaluyeh gas refinery
Authors: Shabani Mohammad R. , Royaee Sayed J.
Published: May 2019

Disulfide oil (DSO) is produced as a hydrocarbon sulfide waste stream in liquefied petroleum gas and condensate sweetening units in refineries and can cause acute environmental pollutions. In this article, a simple process composed of two units including a distillation unit and a hydrodesulfurization (HDS) unit is proposed to overcome the disulfide oil problem in refineries. The commercial HDS catalyst is CoMo type that is applicable for hydrotreating of DSO. This catalyst is developed by different licensors such as Axens. The high sulfur content in DSO feed causes an increase in heat of reaction and partial pressure of H2S in HDS reactor. By using special design techniques such as reactor quenching or increase H2/oil ratio, the reactor can be designed properly for DSO feed. The waste stream DSO is converted to valuable products including: dimethyl disulfide (DMDS), sweet gas and condensate. A process flow diagram consisting of distillation and HDS units together with amine treating and hydrogen compression system is proposed and simulation of the process is carried out by Aspen plus: The distillation unit separates DMDS and the HDS unit removes sulfur from remainder DSO. Capital cost estimation methodology is based on bare module factor. The capital and operating cost of the process are estimated for a real capacity of DSO just produced in south pars of Iran. Financial parameters and sensitivity analysis show that the process is feasible both technically and economically with an internal rate of return of 73.6%. The proposed process is accepted environmentally by converting a harmful waste to saleable products.
Correlation and principal component regression analysis for studying air quality and meteorological elements in Wuhan, China
Authors: Song Zhe , Deng Qinli , Ren Zhigang
Published: May 2019

The states of human health and the environment are closely related to air quality (AQ). Further, in addition to pollutant emissions, meteorological elements are key factors that affect AQ. In this study, variations in the air quality index (AQI) were analyzed; the relationships between AQI and meteorological elements during 2013–2017 in Wuhan were examined, using the Pearson correlation coefficient (PCC) technique. Meanwhile, the principal component regression (PCR) technique was used to predict the daily AQI based on the previous day's AQI and five meteorological variables. An obvious seasonal pattern was seen in the AQI variations. Temperature, relative humidity, precipitation, and wind speed were negatively correlated with AQI, while atmospheric pressure was positively correlated with AQI for the entire study period. The performance of the PCR model was evaluated using different statistical indicators. The results showed that the PCR model could predict the daily AQI effectively at all six monitoring stations with determination coefficient (R2) values of 0.549, 0.563, 0.561, 0.596, 0.534, and 0.602, respectively.