bluuebunny/crossref_metadata_2025 huggingface dataset:
Bidirectional associations between affective empathy and proactive and reactive aggression
Authors: Tampke Elizabeth C. , Fite Paula J. , Cooley John L.
Published: March 2020

Preliminary evidence indicates that affective empathy is differentially related to proactive and reactive functions of aggression. However, additional longitudinal research is needed to understand the potential reciprocal nature of these links. The current study examined the bidirectional associations between affective empathy and proactive and reactive aggression over a 6‐month period during middle childhood, with attention to potential gender differences. Data were collected from 294 elementary school children (52% girls; M = 9.25 years; SD = 0.944 years) and their homeroom teachers. Affective empathy was assessed using self‐reports, and teachers provided ratings of children's functions of aggression. Data were collected during the fall and spring of one academic year. Overall, results suggest some evidence that affective empathy and functions of aggression are reciprocally linked over time. As predicted, Time 1 empathy was inversely associated with Time 2 proactive aggression and Time 1 reactive aggression was inversely associated with Time 2 empathy. Contrary to expectations, Time 1 proactive aggression was marginally positively associated with Time 2 empathy, and Time 1 empathy was not significantly associated with Time 2 reactive aggression. These prospective links did not differ according to gender. Implications and directions for future research are discussed.
Self‐reported rates of impulsivity in Parkinson’s Disease
Authors: Aumann Megan A. , Stark Adam J. , Hughes Shelby B. , Lin Ya‐Chen , Kang Hakmook , Bradley Elise , Zald David H. , Claassen Daniel O.
Published: March 2020

Objective

Impulsive decision‐making is characterized by actions taken without considering consequences. Patients with Parkinson's disease (PD) who receive dopaminergic treatment, especially dopamine agonists, are at risk of developing impulsive–compulsive behaviors (ICBs). We assessed impulse‐related changes across a large heterogeneous PD population using the Barratt impulsivity scale (BIS‐11) by evaluating BIS‐11 first‐ and second‐order factors.

Methods

We assessed a total of 204 subjects: 93 healthy controls (HCs), and 68 ICB– and 43 ICB + PD patients who completed the BIS‐11. Using a general linear model and a least absolute shrinkage and selection operation regression, we compared BIS‐11 scores between the HC, ICB– PD, and ICB + PD groups.

Results

Patients with PD rated themselves as more impulsive than HCs in the BIS‐11 total score, second‐order attention domain, and first‐order attention and self‐control domains. ICB + patients recorded higher total scores as well as higher scores in the second‐order non‐planning domain and in self‐control and cognitive complexity than ICB– patients.

Interpretation

These results indicate that the patients with PD show particular problems with attentional control, whereas ICB + patients show a distinct problem in cognitive control and complexity. Additionally, it appears that all patients with PD are more impulsive than their age‐ and sex‐matched healthy peers. Increased impulsivity may be a result of the disease course, or attributed to dopaminergic medication use, but these results emphasize the importance of the cognitive components of impulsivity in patients with PD.
Corrosion in Hank's Solution and Mechanical Strength of Ultrafine‐Grained Pure Iron
Authors: Batista Beatriz Araújo , Soares Renata Braga , Lins Vanessa de Freitas Cunha , Figueiredo Roberto Braga , Hohenwarter Anton , Matencio Tulio
Published: March 2020

In recent years, there has been a growing interest in developing biodegradable implants which are absorbed by the body after fulfilling a task. Pure iron is a candidate for such applications because it is considered biocompatible and it does not passivate in physiological media. Herein, the potential to increase the strength of pure iron through grain refinement is evaluated to allow a reduction in size of implants and its effect on corrosion behavior. High‐pressure torsion is applied to process pure iron and to refine the grain size of less than 1 μm. Annealing at different temperatures is used to produce samples with different grain sizes. Compression tests show a significant increase in flow stress to over 1 GPa in samples with very small grain sizes. However, such structure is associated with negligible strain hardening and strain‐rate sensitivity. Electrochemical and immersion tests in Hank's solution show that the grain refinement reduces the corrosion rate significantly. Samples with grain sizes smaller than 1 μm display uniform corrosion and develop a homogeneous surface layer of corrosion products. Thus, severe plastic deformation followed by annealing produces mechanically stronger pure iron with reduced biodegradability.
An Effective Method for Recovering Nonradiative Recombination Loss in Scalable Organic Solar Cells
Authors: Xing Zhi , Meng Xiangchuan , Sun Rui , Hu Ting , Huang Zengqi , Min Jie , Hu Xiaotian , Chen Yiwang
Published: March 2020

Regarded as a critical step in commercial applications, scalable printing technology has become a research frontier in the field of organic solar cells. However, inevitable efficiency loss always occurs in the lab‐to‐manufacturing translation due to the different fabrication processes. In fact, the decline of photovoltaic performance is mainly related to voltage loss, which is mainly affected by the diversity of phase separation morphology and the chemical structures of photoactive materials. Fullerene derivative indene‐C60 bisadduct (ICBA) is introduced into a PBDB‐T‐2F:IT‐4F system to control the active layer morphology during blade‐coating process. Accordingly, as a symmetrical fullerene derivative, ICBA can regulate the crystallization tendency and molecular packing orientation and suppress charge carrier recombination. This ternary strategy overcomes the morphology issues caused by weaker shear impulse in blade‐coating process. Benefiting from the reduced nonradiative recombination loss, 1.05 cm2 devices are fabricated by blade coating with a power conversion efficiency of 13.70%. This approach provides an effective support for recovering the voltage loss during scalable printing approaches.
Transition‐Metal Dichalcogenide NiTe2: An Ambient‐Stable Material for Catalysis and Nanoelectronics
Authors: Nappini Silvia , Boukhvalov Danil W. , D'Olimpio Gianluca , Zhang Libo , Ghosh Barun , Kuo Chia‐Nung , Zhu Haoshan , Cheng Jia , Nardone Michele , Ottaviano Luca , Mondal Debashis , Edla Raju , Fuji Jun , Lue Chin Shan , Vobornik Ivana , Yarmoff Jory A. , Agarwal Amit , Wang Lin , Zhang Lixue , Bondino Federica , Politano Antonio
Published: March 2020

By means of theory and experiments, the application capability of nickel ditelluride (NiTe2) transition‐metal dichalcogenide in catalysis and nanoelectronics is assessed. The Te surface termination forms a TeO2 skin in an oxygen environment. In ambient atmosphere, passivation is achieved in less than 30 min with the TeO2 skin having a thickness of about 7 Å. NiTe2 shows outstanding tolerance to CO exposure and stability in water environment, with subsequent good performance in both hydrogen and oxygen evolution reactions. NiTe2‐based devices consistently demonstrate superb ambient stability over a timescale as long as one month. Specifically, NiTe2 has been implemented in a device that exhibits both superior performance and environmental stability at frequencies above 40 GHz, with possible applications as a receiver beyond the cutoff frequency of a nanotransistor.
Conversion‐Type MnO Nanorods as a Surprisingly Stable Anode Framework for Sodium‐Ion Batteries
Authors: Wang Shitong , Dong Yanhao , Cao Fangjun , Li Yutong , Zhang Zhongtai , Tang Zilong
Published: March 2020

The emergence of nanomaterials in the past decades has greatly advanced modern energy storage devices. Nanomaterials can offer high capacity and fast kinetics yet are prone to rapid morphological evolution and degradation. As a result, they are often hybridized with a stable framework in order to gain stability and fully utilize its advantages. However, candidates for such framework materials are rather limited, with carbon, conductive polymers, and Ti‐based oxides being the only choices; note these are all inactive or intercalation compounds. Conventionally, alloying‐/conversion‐type electrodes, which are thought to be electrochemically unstable by themselves, have never been considered as framework materials. This concept is challenged. Successful application of conversion‐type MnO nanorod as a anode framework for high‐capacity Mo2C/MoOx nanoparticles has been demonstrated in sodium‐ion batteries. Surprisingly, it can stably deliver 110 mAh g−1 under extremely high rate of 8000 mA g−1 (≈70 C) over 40 000 cycles with no capacity decay. More generally, this is considered as a proof of concept and much more alloying‐/conversion‐type materials are expected to be explored for such applications.
Graphene‐Assisted Epitaxy of Nitrogen Lattice Polarity GaN Films on Non‐Polar Sapphire Substrates for Green Light Emitting Diodes
Authors: Liu Fang , Zhang Zhihong , Rong Xin , Yu Ye , Wang Tao , Sheng Bowen , Wei Jiaqi , Zhou Siyuan , Yang Xuelin , Xu Fujun , Qin Zhixin , Zhang Yuantao , Liu Kaihui , Shen Bo , Wang Xinqiang
Published: March 2020

Lattice polarity is a key point for hexagonal semiconductors such as GaN. Unfortunately, only Ga‐polarity GaN have been achieved on graphene till now. Here, the epitaxy of high quality nitrogen‐polarity GaN films on transferred graphene on non‐polar sapphire substrates by molecular beam epitaxy is reported. This success is achieved through atomic nitrogen irradiation, where CN bonds are formed in graphene and provide nucleation sites for GaN and leading to N‐polarity GaN epitaxy. The N‐polarity characteristics are confirmed by chemical etching and transmission electron microscopy measurement. Due to the higher growth temperature of InGaN at N‐polarity than that at Ga‐polarity, green light emitting diodes are fabricated on the graphene‐assisted substrate, where a large redshift of emission wavelength is observed. These results open a new avenue for the polarity modulation of III‐nitride films based on 2D materials, and also pave the way for potential application in longer wavelength light emitting devices.
Universal Elaboration of Al‐Doped TiO2 as an Electron Extraction Layer in Inorganic–Organic Hybrid Perovskite and Organic Solar Cells
Authors: Kim Jun Young , Rhee Seunghyun , Lee Hyunho , An Kunsik , Biswas Swarup , Lee Yongju , Shim Jae Won , Lee Changhee , Kim Hyeok
Published: March 2020

Fabricating an electron extraction layer (EEL) with a metal doping transition metal oxide (TMO) in inorganic–organic hybrid perovskite solar cells (PeSCs) and organic solar cells (OSCs) is a simple and efficient process for enhancing photovoltaic properties. Here, the universal benefits and common factors that influence both PeSCs and OSCs as a result of changes in Al‐doped TiO2 properties are investigated. These common factors are identified in two separate mechanisms. The first involves surface smoothing of TiO2 films, which affects the formation of a high crystalline active layer and reduces recombination between the electron extraction and active layers. The second involves bandgap widening of TiO2, which reduces the activation energy and enhances the quenching efficiency of devices. These factors are demonstrated in various measurements. The results will help in understanding the fundamental benefits of Al‐doped TiO2 in solution‐processed thin‐film solar cells.
Effect of the Degree of the Gate‐Dielectric Surface Roughness on the Performance of Bottom‐Gate Organic Thin‐Film Transistors
Authors: Geiger Michael , Acharya Rachana , Reutter Eric , Ferschke Thomas , Zschieschang Ute , Weis Jürgen , Pflaum Jens , Klauk Hagen , Weitz Ralf Thomas
Published: March 2020

In organic thin‐film transistors (TFTs) fabricated in the inverted (bottom‐gate) device structure, the surface roughness of the gate dielectric onto which the organic‐semiconductor layer is deposited is expected to have a significant effect on the TFT characteristics. To quantitatively evaluate this effect, a method to tune the surface roughness of a gate dielectric consisting of a thin layer of aluminum oxide and an alkylphosphonic acid self‐assembled monolayer over a wide range by controlling a single process parameter, namely the substrate temperature during the deposition of the aluminum gate electrodes, is developed. All other process parameters remain constant in the experiments, so that any differences observed in the TFT performance can be confidently ascribed to effects related to the difference in the gate‐dielectric surface roughness. It is found that an increase in surface roughness leads to a significant decrease in the effective charge‐carrier mobility and an increase in the subthreshold swing. It is shown that a larger gate‐dielectric surface roughness leads to a larger density of grain boundaries in the semiconductor layer, which in turn produces a larger density of localized trap states in the semiconductor.
Topological Space‐Time Photonic Transitions in Angular‐Momentum‐Biased Metasurfaces
Authors: Barati Sedeh Hooman , Salary Mohammad Mahdi , Mosallaei Hossein
Published: March 2020

In this paper, topological space‐time photonic transition of light in angular‐momentum‐biased metasurfaces is established, which yields a superposition of orbital‐angular‐momentum (OAM)‐carrying beams at distinct frequency harmonics upon scattering whose topological charges and frequency shifts are correlated. A reflective dielectric metasurface is considered that consists of silicon nanodisk heterostructures integrated with indium‐tin‐oxide and gate dielectric layers placed on a back mirror forming a dual‐gated field effect modulator. The metasurface is divided into several azimuthal sections wherein the nanodisk heterostructures are interconnected via biasing lines. Addressing each azimuthal section with radio‐frequency biasing signals separately allows for flexible implementation of different spatiotemporal modulation profiles. Active tuning of OAM states with high mode‐purity is demonstrated, which yields minimal cross‐talk between OAM channels in a mode‐multiplexed communication system. Moreover, the role of spatiotemporal modulation profile on the spectral and spatial diversity of OAM states is explored. It is shown that angular‐momentum‐biased metasurfaces allow opportunities for hybridized mode‐division and wavelength‐division multiple access through multiplexing and multicasting across distinct OAM states and wavelengths. The nonreciprocity of topological space‐time photonic transitions across the temporal frequency domain and Hilbert space of OAM states is also investigated giving rise to distinct twisted light channels in up‐ and down‐links.
Effective Ratiometric Luminescent Thermal Sensor by Cr3+‐Doped Mullite Bi2Al4O9 with Robust and Reliable Performances
Authors: Back Michele , Ueda Jumpei , Xu Jian , Asami Kazuki , Brik Mikhail G. , Tanabe Setsuhisa
Published: March 2020

The design of effective optical systems featuring high thermal sensitivity able to discriminate ever smaller variations of temperature in noncontact mode is of critical importance to face the challenges brought by the modern‐day technological revolution. If from one hand, the ratiometric optical thermometers based on Boltzmann distribution are demonstrated to be characterized by a unique reliability, on the other hand, robust performances in different environments are highly desired for new applications such as in situ thermal sensing of catalytic reactions. Here, the crystal field experienced by Cr3+ in Bi2Al4O9 is investigated demonstrating the potential of this system as ratiometric self‐referencing thermal sensor being characterized by high relative sensitivity (1.24% K−1 at 290 K). The remarkable absolute sensitivity results in an exceptional low thermal resolution of ≈0.2 K, 15‐fold lower than for the conventional Nd3+‐based thermometers used in biological applications. The comparison of the performances among different systems evidences the potential of Cr3+‐based thermometers with thermal resolution even lower than the state of the art diamond. In addition, the pH dependence of the photoluminescence emission confirms a high stability also at extreme conditions of basic and acid environments and the aging effects are tested for one week.
Large Out‐of‐Plane Second Harmonic Generation Susceptibility in Penta‐ZnS2 Sheet
Authors: Shen Yiheng , Guo Yaguang , Wang Qian
Published: March 2020

Second harmonic generation (SHG) of 2D materials has received considerable attention because of the enhanced response to the incident light as compared to that of their bulk counterparts. A significant SHG effect in a new 2D pentagon‐based structure of ZnS2 sheet, penta‐ZnS2, is reported for the first time. On the basis of first‐principles calculations combined with global structure search and independent particle approximation, penta‐ZnS2 is found to be dynamically, thermally, and mechanically stable. Unlike most reported 2D materials with only in‐plane SHG response, penta‐ZnS2 exhibits giant out‐of‐plane SHG susceptibility, which is two to three orders of magnitude larger than that of Janus 2D materials, due to the lack of centrosymmetry and out‐of‐plane mirror symmetry of its geometric structure. The underlying mechanism of the large SHG effect can be applied to other pentagon‐based sheets consisting of different elements, thus expanding the family of 2D materials with strong out‐of‐plane SHG response.
Common mycorrhizal networks contribute to overyielding in faba bean/coix intercropping systems
Authors: Qiao Xu , Guo Xinwei , Li Ailian
Published: March 2020

Intercropping typically results in overyielding, particularly in sustainable, low‐input agriculture systems. We designed a greenhouse experiment to understand how common mycorrhizal networks (CMNs) regulate intra‐ and inter‐specific plant−plant interactions in intercropping systems, utilizing microcosms divided into one inner and four outer compartments. The inner compartment was separated from the outer compartments by a 0.45 μm mesh (+Soil water and nutrients−CMNs−Roots), a 30 μm mesh (+Soil water and nutrients+CMNs−Roots), a solid barrier (−Soil water and nutrients−CMNs−Roots), and no barrier (+Soil water and nutrients+CMNs+Roots). Both faba bean (Vicia faba L.) and coix (Coix lachryrma‐jobi L.) were grown as the donor plants in the inner compartment. The plant combinations were donor coix−receiver coix, donor coix−receiver faba bean, donor faba bean−receiver faba bean, and donor faba bean−receiver coix. The inner compartment was inoculated with Flomus intraradices, or Funneliformis mosseae, or remained noninoculated in soil with low P content (< 5 g/kg soil). Our study found that there were clear advantages of interspecific interaction (coix/faba bean combination) over intraspecific (coix/coix and faba bean/faba bean combinations) in the both presence and absence of arbuscular mycorrhizal fungus (AMF). The establishment of CMNs appears to promote intra‐ and inter‐specific interactions between donor and receiver plants, and exhibits strong positive effects on plant growth and P uptake. The contribution to plant growth and P uptake of CMNs formed by F. mosseae was greater than by F. intraradices.
Optimization of the amines‐CO2 capture process by a nonequilibrium rate‐based modeling approach
Authors: López‐Bautista Luis Angel , Flores‐Tlacuahuac Antonio
Published: March 2020

Amine‐based chemical absorption has become the most mature technology among carbon dioxide capture processes, featuring the advantages of high separation efficiencies and its simplicity to attach it to existent industrial facilities. Nevertheless, further improvements on its performance are required in order to implement this technology to a wider extent. Energy expenditure at the solvent regeneration unit has been remarked as the major drawback of the process under discussion; therefore, the main objective of this work is to compute optimal operating policies which ensure minimum heat load at the reboiler along with reasonable removal efficiencies. A deterministic mathematical model of a reported pilot plant was deployed as the basis for the nonlinear programming optimization formulations, using a rate‐based approach and an eNRTL thermodynamic framework. Several optimization scenarios were studied to account for diverse capture targets and degrees of freedom. Furthermore, sensitivity analyses were performed to understand the stand‐alone effect of some variables on the process. Results reflect the importance of optimizing the complete plant to account for significant interactions between variables, as well as choosing an operational arrangement according to the separation goal demanded.
A scoping review to identify strategies that work to prevent four important occupational diseases
Authors: Keefe Anya R. , Demers Paul A. , Neis Barbara , Arrandale Victoria H. , Davies Hugh W. , Gao Zhiwei , Hedges Kevin , Holness D. Linn , Koehoorn Mieke , Stock Susan R. , Bornstein Stephen
Published: March 2020

Background

Despite being largely preventable, many occupational diseases continue to be highly prevalent and extremely costly. Effective strategies are required to reduce their human, economic, and social impacts.

Methods

To better understand which approaches are most likely to lead to progress in preventing noise‐related hearing loss, occupational contact dermatitis, occupational cancers, and occupational asthma, we undertook a scoping review and consulted with a number of key informants.

Results

We examined a total of 404 articles and found that various types of interventions are reported to contribute to occupational disease prevention but each has its limitations and each is often insufficient on its own. Our principal findings included: legislation and regulations can be an effective means of primary prevention, but their impact depends on both the nature of the regulations and the degree of enforcement; measures across the hierarchy of controls can reduce the risk of some of these diseases and reduce exposures; monitoring, surveillance, and screening are effective prevention tools and for evaluating the impact of legislative/policy change; the effect of education and training is context‐dependent and influenced by the manner of delivery; and, multifaceted interventions are often more effective than ones consisting of a single activity.

Conclusions

This scoping review identifies occupational disease prevention strategies worthy of further exploration by decisionmakers and stakeholders and of future systematic evaluation by researchers. It also identified important gaps, including a lack of studies of precarious workers and the need for more studies that rigorously evaluate the effectiveness of interventions.
Exploring and Using Business Solutions In Mediation Settlement Agreements
Authors: Thompson Roderick M.
Published: March 2020

It has long been recognized that one of mediation's great strengths is that the parties are not limited to the narrow, binary win‐lose results available in litigated resolutions.
Who Cares? Me and You, But Never ‘I’
Authors: Creo Robert A.
Published: March 2020

There is no “I” in TEAM!
“Anti‐elektrostatische” Halogenbrücken
Authors: Holthoff Jana M. , Engelage Elric , Weiss Robert , Huber Stefan M.
Published: March 2020

Halogenbrücken (XB) werden oft als primär elektrostatische Wechselwirkung beschrieben. Deshalb scheinen Addukte zwischen anionischen XB‐Donoren (halogen‐basierten Lewis‐Säuren) und Anionen der Intuition zu widersprechen. Solche “anti‐elektrostatischen” XBs wurden anhand von theoretischen Studien vorhergesagt, für organische XB‐Donoren sind jedoch keine experimentellen Beispiele bekannt, mit Ausnahme einiger weniger Fälle von Selbstassoziation. Im Rahmen dieser Veröffentlichung berichten wir von der Synthese zweier anionischer Organoiodverbindungen, die auf ihre Befähigung zur Ausbildung “anti‐elektrostatischer” XBs mit Anionen untersucht wurden. Obwohl das elektrostatische Potential auf der gesamten Oberfläche beider Verbindungen durchgängig negativ ist, weisen DFT‐Rechnungen auf eine kinetische Stabilisierung der entsprechenden Halogenidkomplexe in der Gasphase und insbesondere in Lösung hin. Experimentell konnte die Selbstassoziation zu Ketten, Dimeren und Trimeren der anionischen XB‐Donoren im Kristall beobachtet werden. Zusätzlich konnten Cokristalle mit Halogenid‐Ionen erhalten werden. Diese sind das erste Beispiel für Halogenbrücken zwischen organischen anionischen XB‐Donoren und strukturell unterschiedlichen Anionen. Die Bindungslängen aller beobachteten Addukte sind 14–21 % kürzer als die Summe der Van‐der‐Waals‐Radien.
Photocatalytic Difunctionalization of Vinyl Ureas by Radical Addition Polar Truce–Smiles Rearrangement Cascades
Authors: Abrams Roman , Clayden Jonathan
Published: March 2020

We report tandem alkyl‐arylations and phosphonyl‐arylations of vinyl ureas by way of a photocatalytic radical‐polar crossover mechanism. Addition of photoredox‐generated radicals to the alkene forms a new C−C or C−P bond and generates a product radical adjacent to the urea function. Reductive termination of the photocatalytic cycle generates an anion that undergoes a polar Truce–Smiles rearrangement, forming a C−C bond. The reaction is successful with a range of α‐fluorinated alkyl sodium sulfinate salts and diarylphosphine oxides as radical precursors, and the conformationally accelerated Truce–Smiles rearrangement is not restricted by the electronic nature of the migrating aromatic ring. Formally the reaction constitutes an α,β‐difuctionalisation of a carbon–carbon double bond, and proceeds under mild conditions with visible light and a readily available organic photocatalyst. The products are α,α‐diaryl alkylureas typically functionalized with F or P substituents that may be readily converted into α,α‐diaryl alkylamines.
High‐Valent Metal–Oxo Species at the Nodes of Metal–Triazolate Frameworks: The Effects of Ligand Exchange and Two‐State Reactivity for C−H Bond Activation
Authors: Rosen Andrew S. , Notestein Justin M. , Snurr Randall Q.
Published: March 2020

Through quantum‐chemical calculations, we investigate a family of metal–organic frameworks (MOFs) containing triazolate linkers, M2X2(BBTA) (M=metal, X=bridging anion, H2BBTA=1H,5H‐benzo(1,2‐d:4,5‐d′)bistriazole), for their ability to form terminal metal–oxo sites and subsequently activate the C−H bond of methane. By varying the metal and bridging anion in the framework, we show how to significantly tune the reactivity of this series of MOFs. The electronic structure of the metal–oxo active site is analyzed for each combination of metal and bridging ligand, and we find that spin density localized on the oxo ligand is not an inherent requirement for low C−H activation barriers. For the Mn‐ and Fe‐containing frameworks, a transition from ferromagnetic to antiferromagnetic coupling between the metal binding site and terminal oxo ligand during the C−H activation process can greatly reduce the kinetic barrier, a unique case of two‐state reactivity without a change in the net spin multiplicity.
A Double Cation–π‐Driven Strategy Enabling Two‐Dimensional Supramolecular Polymers as Efficient Catalyst Carriers
Authors: Xiao Xuedong , Chen Hongbo , Dong Xuxu , Ren Dazhuo , Deng Qiang , Wang Dapeng , Tian Wei
Published: March 2020

The cation–π interaction is a strong non‐covalent interaction that can be used to prepare high‐strength, stable supramolecular materials. However, because the molecular plane of a cation‐containing group and that of aromatic structure are usually perpendicular when forming a cation–π complex, it is difficult to exploit the cation–π interaction to prepare a 2D self‐assembly in which the molecular plane of all the building blocks are parallel. Herein, a double cation–π‐driven strategy is proposed to overcome this difficulty and have prepared 2D self‐assemblies with long‐range ordered molecular hollow hexagons. The double cation–π interaction makes the 2D self‐assemblies stable. The 2D self‐assemblies are to be an effective carrier that can eliminate metal‐nanoparticle aggregation. Such 2D assembly/palladium nanoparticle hybrids are shown to exhibit recyclability and superior catalytic activity for a model reaction.
Alkyl Carbazates for Electrochemical Deoxygenative Functionalization of Heteroarenes
Authors: Gao Yongyuan , Wu Zhengguang , Yu Lei , Wang Yi , Pan Yi
Published: March 2020

The C−O bond cleavage for activation of alcohols is synthetically useful and practically challenging. This work describes carbazate as a new type of electrochemically activated alkylating agent derived from ubiquitous alcohols for direct functionalization of heteroarenes under mild electrolytic conditions. The simple undivided cell at low oxidative potentials with carbon/platinum electrode set‐ups offers excellent substrate tolerance, affording a variety of primary, secondary and tertiary alkyl‐decorated heterocycles in good chemical yields. Furthermore, the mechanism for this electrochemical deoxyalkylation reaction has been investigated.
Two Distinct Structures of Membrane‐Associated Homodimers of GTP‐ and GDP‐Bound KRAS4B Revealed by Paramagnetic Relaxation Enhancement
Authors: Lee Ki‐Young , Fang Zhenhao , Enomoto Masahiro , Gasmi‐Seabrook Genevieve , Zheng Le , Koide Shohei , Ikura Mitsuhiko , Marshall Christopher B.
Published: March 2020

KRAS homo‐dimerization has been implicated in the activation of RAF kinases, however, the mechanism and structural basis remain elusive. We developed a system to study KRAS dimerization on nanodiscs using paramagnetic relaxation enhancement (PRE) NMR spectroscopy, and determined distinct structures of membrane‐anchored KRAS dimers in the active GTP‐ and inactive GDP‐loaded states. Both dimerize through an α4–α5 interface, but the relative orientation of the protomers and their contacts differ substantially. Dimerization of KRAS‐GTP, stabilized by electrostatic interactions between R135 and E168, favors an orientation on the membrane that promotes accessibility of the effector‐binding site. Remarkably, “cross”‐dimerization between GTP‐ and GDP‐bound KRAS molecules is unfavorable. These models provide a platform to elucidate the structural basis of RAF activation by RAS and to develop inhibitors that can disrupt the KRAS dimerization. The methodology is applicable to many other farnesylated small GTPases.
Slurry‐Coated Sulfur/Sulfide Cathode with Li Metal Anode for All‐Solid‐State Lithium‐Sulfur Pouch Cells
Authors: Yuan Hong , Nan Hao‐Xiong , Zhao Chen‐Zi , Zhu Gao‐Long , Lu Yang , Cheng Xin‐Bing , Liu Quan‐Bing , He Chuan‐Xin , Huang Jia‐Qi , Zhang Qiang
Published: March 2020

All‐solid‐state lithium‐sulfur batteries are strongly considered as the most promising next‐generation electrochemical energy storage systems due to their high safety and energy density. However, in view of practical application, it is difficult to obtain large‐scale solid‐state sulfur cathode continuously. Herein we achieve the large‐scale fabrication of solid sulfur cathode by a facile slurry‐coating process through the screening of various solvents and binder contents. The composite cathodes in all‐solid‐state lithium‐sulfur pouch cells exhibit a high specific capacity of 1169 mAh g−1 and excellent cycling stability. Furthermore, a practical lithium‐sulfur pouch cell with an areal discharge capacity of up to 2.3 mAh cm−2 is also demonstrated. This work makes a leap towards the practical application of all‐solid‐state lithium‐sulfur batteries.
Introducing the 21st Century's New Four Horsemen of the Coronapocalypse
Authors: Cheong Kang Hao , Jones Michael C.
Published: March 2020

As the world struggles through the COVID‐19 pandemic, we should also be asking what systems‐level measures will be needed to prevent this or even worse disasters from happening in the future. We argue that the pandemic is merely one of potentially myriad and pleiomorphic future global disasters generated by the same underlying dynamical system. We explain that there are four broad but easily identifiable systemic, pathologically networked conditions that are hurtling civilization toward potential self‐destruction. As long as these conditions are not resolved, we should consider catastrophe as an inevitable emergent endpoint from the dynamics. All four conditions can be reversed with collective action to begin creating an enduring and thriving post‐ COVID‐19 world. This will require maximal application of the precautionary principle.
Improved confidence intervals for a difference of two cause‐specific cumulative incidence functions estimated in the presence of competing risks and random censoring
Authors: Scosyrev Emil
Published: March 2020

A cause‐specific cumulative incidence function (CIF) is the probability of failure from a specific cause as a function of time. In randomized trials, a difference of cause‐specific CIFs (treatment minus control) represents a treatment effect. Cause‐specific CIF in each intervention arm can be estimated based on the usual non‐parametric Aalen–Johansen estimator which generalizes the Kaplan–Meier estimator of CIF in the presence of competing risks. Under random censoring, asymptotically valid Wald‐type confidence intervals (CIs) for a difference of cause‐specific CIFs at a specific time point can be constructed using one of the published variance estimators. Unfortunately, these intervals can suffer from substantial under‐coverage when the outcome of interest is a rare event, as may be the case for example in the analysis of uncommon adverse events. We propose two new approximate interval estimators for a difference of cause‐specific CIFs estimated in the presence of competing risks and random censoring. Theoretical analysis and simulations indicate that the new interval estimators are superior to the Wald CIs in the sense of avoiding substantial under‐coverage with rare events, while being equivalent to the Wald CIs asymptotically. In the absence of censoring, one of the two proposed interval estimators reduces to the well‐known Agresti–Caffo CI for a difference of two binomial parameters. The new methods can be easily implemented with any software package producing point and variance estimates for the Aalen–Johansen estimator, as illustrated in a real data example.
Sitagliptin affects gastric cancer cells proliferation by suppressing Melanoma‐associated antigen‐A3 expression through Yes‐associated protein inactivation
Authors: Wang Qi , Lu Pan , Wang Tao , Zheng Qianqian , Li Yan , Leng Sean X. , Meng Xin , Wang Biao , Xie Jisheng , Zhang Haiyan
Published: March 2020

Sitagliptin is an emerging oral hypoglycemic agent that inhibits the development of a wide variety of tumors. Current researches indicate that the abnormal activation of Yes‐associated protein (YAP) promotes the proliferation and poor prognosis of multiple tumors. However, the ability of sitagliptin to regulate YAP and its effects on gastric cancer (GC) cells remain unclear. Here, we first showed that sitagliptin inhibited the proliferation of GC cells, and this inhibition was regulated by Hippo pathway. Sitagliptin phosphorylated YAP in a large tumor suppressor homolog‐dependent manner, thereby inhibiting YAP nuclear translocation, and promoted YAP cytoplasm retention. This inhibition can be blocked by adenosine 5′‐monophosphate‐activated protein kinase (AMPK). Moreover, sitagliptin could reduce the expression of tumor‐testis antigen Melanoma‐associated antigen‐A3 through YAP. In conclusion, sitagliptin may have a potential inhibitory effect on GC by AMPK/YAP/melanoma‐associated antigen‐A3 pathway.
Understanding Substrate Selectivity of Phoslactomycin Polyketide Synthase by Using Reconstituted in Vitro Systems
Authors: Geyer Kyra , Sundaram Srividhya , Sušnik Peter , Koert Ulrich , Erb Tobias J.
Published: March 2020

Polyketide synthases (PKSs) use simple extender units to synthesize complex natural products. A fundamental question is how different extender units are site‐specifically incorporated into the growing polyketide. Here we established phoslactomycin (Pn) PKS, which incorporates malonyl‐ and ethylmalonyl‐CoA, as an in vitro model to study substrate specificity. We combined up to six Pn PKS modules with different termination sites for the controlled release of tetra‐, penta‐ and hexaketides, and challenged these systems with up to seven different extender units in competitive assays to test for the specificity of Pn modules. While malonyl‐CoA modules of Pn PKS exclusively accept their natural substrate, the ethylmalonyl‐CoA module PnC tolerates different α‐substituted derivatives, but discriminates against malonyl‐CoA. We show that the ratio of extender transacylation to hydrolysis controls incorporation in PnC, thus explaining site‐specific selectivity and promiscuity in the natural context of Pn PKS.
Pure Hydrogen and Propylene Coproduction in Catalytic Membrane Reactor‐Assisted Propane Dehydrogenation
Authors: Saidi Majid , Safaripour Maryam
Published: March 2020

Propane dehydrogenation on a commercial Pt‐Sn/Al2O3 catalyst in a Pd‐Ag membrane reactor is considered. A mathematical model is developed to evaluate the performance of the catalytic membrane reactor for the process of propane dehydrogenation. Design and operating conditions are systematically evaluated for key performance metrics such as propane conversion, propylene selectivity, hydrogen selectivity, and hydrogen recovery under different operating conditions. The results confirm that the high performance of the membrane reactor is related to the continuous removal of hydrogen from the reaction zone to shift the reaction equilibrium towards the formation of more propylene and hydrogen.
Thermal Hysteresis and Bursting Rate in Sucrose Solutions with Antifreeze Proteins
Authors: Kiran-Yildirim Bercem , Gaukel Volker
Published: March 2020

Antifreeze proteins (AFPs) modify the ice shape and inhibit further growth leading to thermal hysteresis (TH). Numerous studies have been performed with the addtition of AFPs to preserve frozen products but the influence of sucrose on the effects of AFPs has not been investigated as of yet. Therefore, the TH activities of type I antifreeze protein (AFP I) and antifreeze glycoprotein (AFGP) were measured as a function of concentration, type of AFPs, and also sucrose concentration. The results showed that the TH values rose with increase in concentration of AFPs and sucrose concentration. The crystals experienced shape modification and grew in the c‐axis direction in the presence of both AFPs. The bursting rate of crystals changed depending on both the concentrations of AFPs and sucrose.
Analysis of Transient Inhomogeneous Flow and Thermal Characteristics in a Drying Room via Large Eddy Simulation
Authors: Li Jin , Zhao Peng , Shi Yajun , Chang Xing , Zhang Chungang , Guo Yong , Liu Yali , Liu Chongying , Chen Yan , Yin Dachuan
Published: March 2020

To optimize the flow structure in a soft‐capsule drying room, the notable inhomogeneous characteristics of flow behavior and thermal feature are numerically explored. An advanced three‐dimensional numerical model is established and a verified large eddy simulation (LES) model is adopted. The results indicated that there is a highly inhomogeneous flow structure especially approaching the bilateral region of the drying room, mainly caused by the large velocity gradient whereas a relatively uniform flow structure is observed in the middle region. In the drying process, the inhomogeneous flow feature is sensitive to the increased inlet velocity and aspect ratio λ. It was found that a suitable inlet velocity and a small aspect ratio λ can provide a better drying flow environment.
Methyl Ethyl Ketone Production through an Intensified Process
Authors: Torres-Vinces Leopoldo , Contreras-Zarazua Gabriel , Huerta-Rosas Brenda , Sánchez-Ramírez Eduardo , Segovia-Hernández Juan Gabriel
Published: March 2020

Methyl ethyl ketone (MEK) is widely used in the industry and is mainly produced from petroleum. Some works have projected MEK as a possible fuel since its performance in spark engines has overcome the performance of gasoline in certain indexes. Two intensified alternatives to produce MEK are introduced here, consisting of a reactive distillation column, an extractive distillation column, and three conventional distillation columns. The direct alternative resulted as the most promising when it was evaluated based on energy consumption, greenhouse gas emissions, and an environmental index. The obtained energy consumption for MEK production was 11.62 MJ kgMEK−1 for the entire process. Moreover, those intensified alternatives showed better performance indexes in comparison with a conventional process.
Staged Condensation of Coal Tar from the Pyrolysis of Coal in a Screw Pyrolyzer
Authors: Liu Ermei , Wang Ze , Li Songgeng , Song Wenli , Zhang Hua
Published: March 2020

Staged condensation of coal tar was studied with a three‐staged condensation system (first stage S1, 100–300 °C; second stage S2, 30–70 °C; third stage S3, 0 °C) to perform on‐line preliminary removal of dust and fundamental fractionation of tar components. The dust and heavy components are predominantly distributed in S1. The polycyclic aromatic hydrocarbons are abundant in S1. Aliphatics and monocyclic phenols are abundant in S2, and the tar in S3 is rich in aliphatics and monocyclic aromatic hydrocarbons. With increasing S2 temperature from 30 to 70 °C, the total organics in the water phase in S2 and S3 are least at an S2 temperature of 50 °C, which is advantageous for post‐treatment of wastewater.
One‐Pot Fabrication of Crumpled N‐Doped Graphene Anchored with Cobalt for High‐Performance Lithium–Sulfur Batteries
Authors: Mao Wutao , Ma Chao , Ni Ping , Li Maolong , Ding Yiming , Zhang Shaojie , Pan Junli , Cao Fengpu , Bao Keyan
Published: March 2020

The commercialization of sulfur batteries is hindered by a few inherent drawbacks. In this study, crumpled N‐doped graphene anchored with cobalt (Co‐NCG) was fabricated in one pot via a sample solvothermal method and applied to lithium‐sulfur (Li−S) batteries. The crumpled structure not only gives graphene a large specific surface area and abundant pores, but also endows graphene superb stability by preventing its restacking; these features are beneficial for loading and efficient utilization of sulfur. The lone pair electrons on the nitrogen atom underwent strong chemical interactions with Li ions, which lent the Co‐NCG/S material the ability to chemically immobilize polysulfide species. Cobalt acts as an electrocatalyst in the battery and kinetically accelerates sulfur redox reactions. As a result of these multifunctional arrangements, the Co‐NCG/S cathode showed excellent capacity retention and reaction kinetics and high sulfur loading capacity.
An Efficient and Stable MoS2/Zn0.5Cd0.5S Nanocatalyst for Photocatalytic Hydrogen Evolution
Authors: Liu Wenxiang , Lu Lele , Li Qiang , Wu Boyuan , Zhang Ruizhe , Shi Wei , Cheng Peng
Published: March 2020

Photocatalytic hydrogen evolution by water splitting is highly important for the application of hydrogen energy and the replacement of fossil fuel by solar energy, which needs the development of efficient catalysts with long‐term catalytic stability under light irradiation in aqueous solution. Herein, Zn0.5Cd0.5S solid solution was synthesized by a metal–organic framework‐templated strategy and then loaded with MoS2 by a hydrothermal method to fabricate a MoS2/Zn0.5Cd0.5S heterojunction for photocatalytic hydrogen evolution. The composition of MoS2/Zn0.5Cd0.5S was fine‐tuned to obtain the optimized 5 wt % MoS2/Zn0.5Cd0.5S heterojunction, which showed a superior hydrogen evolution rate of 23.80 mmol h−1 g−1 and steady photocatalytic stability over 25 h. The photocatalytic performance is due to the appropriate composition and the formation of an intimate interface between MoS2 and Zn0.5Cd0.5S, which endows the photocatalyst with high light‐harvesting ability and effective separation of photogenerated carriers.
Group 6 Oxyfluoro‐Anion Salts of [XeF5]+ and [Xe2F11]+: Syntheses and Structures of [XeF5][M2O2F9] (M=Mo, W), [Xe2F11][M′OF5] (M′=Cr, Mo, W), [XeF5][HF2]⋅CrOF4, and [XeF5][WOF5]⋅XeOF4
Authors: Bortolus Mark R. , Mercier Hélène P. A. , Schrobilgen Gary J.
Published: March 2020

The reactions of the fluoride‐ion donor, XeF6, with the fluoride‐ion acceptors, M′OF4 (M′=Cr, Mo, W), yield [XeF5]+ and [Xe2F11]+ salts of [M′OF5]− and [M2O2F9]− (M=Mo, W). Xenon hexafluoride and MOF4 react in anhydrous hydrogen fluoride (aHF) to give equilibrium mixtures of [Xe2F11]+, [XeF5]+, [(HF)nF]−, [MOF5]−, and [M2O2F9]− from which the title salts were crystallized. The [XeF5][CrOF5] and [Xe2F11][CrOF5] salts could not be formed from mixtures of CrOF4 and XeF6 in aHF at low temperature (LT) owing to the low fluoride‐ion affinity of CrOF4, but yielded [XeF5][HF2]⋅CrOF4 instead. In contrast, MoOF4 and WOF4 are sufficiently Lewis acidic to abstract F− ion from [(HF)nF]− in aHF to give the [MOF5]− and [M2O2F9]− salts of [XeF5]+ and [Xe2F11]+. To circumvent [(HF)nF]− formation, [Xe2F11][CrOF5] was synthesized at LT in CF2ClCF2Cl solvent. The salts were characterized by LT Raman spectroscopy and LT single‐crystal X‐ray diffraction, which provided the first X‐ray crystal structure of the [CrOF5]− anion and high‐precision geometric parameters for [MOF5]− and [M2O2F9]−. Hydrolysis of [Xe2F11][WOF5] by water contaminant in HF solvent yielded [XeF5][WOF5]⋅XeOF4. Quantum‐chemical calculations were carried out for M′OF4, [M′OF5]−, [M′2O2F9]−, {[Xe2F11][CrOF5]}2, [Xe2F11][MOF5], and {[XeF5][M2O2F9]}2 to obtain their gas‐phase geometries and vibrational frequencies to aid in their vibrational mode assignments and to assess chemical bonding.
Dicht‐ und Klebstoffe auf Silikonbasis
Authors: Wolf Andreas T.
Published: March 2020

Der Vergleich verschiedener Anwendungsgebiete von Dicht‐ und Klebstoffen auf Silikonbasis zeigt rasch, dass ihr breites Leistungs‐ und Anwendungsspektrum sowohl auf ihrer Polymerstruktur als auch auf der Formulierung beruht. Diese synthetischen Werkstoffe sind gekennzeichnet durch einen großen Temperatureinsatzbereich, sehr gute elektrische Eigenschaften, hohe Flexibilität, exzellente UV‐Beständigkeit, gute chemische Beständigkeit, hervorragende Witterungsbeständigkeit, geringe Brennbarkeit, keine oder nur sehr geringe Toxizität, sowie einfache Verarbeitung und Anwendung. Diese inhärenten Eigenschaften der Silikone, die auf der besonderen Natur der Siloxanbindung beruhen, können durch Variation der Produktformulierung, zum Beispiel durch den Zusatz von Füllstoffen oder anderen chemischen Additiven, noch verändert werden. Hierdurch lassen sich spezifische Funktionen und Eigenschaften verbessern oder hinzufügen. Ebenso lassen sich über die Formulierung des Kleb‐ oder Dichtstoffes dessen rheologische und mechanische Eigenschaften einstellen sowie die Hafteigenschaften beeinflussen.
Expedient Synthesis of Ketones viaN‐Heterocyclic Carbene/Nickel‐Catalyzed Redox‐Economical Coupling of Alcohols and Alkynes†
Authors: Li Yu‐Qing , Li Feng , Shi Shi‐Liang
Published: March 2020

Summary of main observation and conclusion

An N‐heterocyclic carbene/nickel‐catalyzed direct coupling of alcohols and internal alkynes to form α‐branched ketones has been developed. This methodology provides a new approach to afford branched ketones, which are difficult to access through the hydroacylation of simple internal alkenes with aldehydes. This redox‐neutral and redox‐economical coupling is free from any oxidative or reductive additives as well as stoichiometric byproducts. These reactions convert both benzylic and aliphatic alcohols and alkynes, two basic feedstock chemicals, into various α‐branched ketones in a single chemical step.