bluuebunny/crossref_metadata_2025_split huggingface dataset:
Constraining the Ratio of Micrometeoroids From Short‐ and Long‐Period Comets at 1 AU From LADEE Observations of the Lunar Dust Cloud
Authors: Janches Diego , Pokorný Petr , Sarantos Menelaos , Szalay Jamey R. , Horányi Mihaly , Nesvorný David 
Published: January 2018

AbstractWe interpret recent observations of the secondary dust ejecta cloud around the Moon from the Lunar Dust Experiment (LDEX) on board the NASA Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft with help from dynamical models of meteoroids. Results suggest that in order to match the spatial structure of observed ejecta profiles, the flux of meteoroids on the Moon must be primarily provided by short‐period comets with an excess ratio of at least 1.3:1 compared to long‐period comets. This ratio increases significantly if the dependence of the ejecta yield on impactor velocity is stronger than generally believed. The model accounts for the orbital geometry of LADEE and shows no indication of a large asymmetry in the meteoroid flux impacting from the Helion and Anti‐Helion directions.
Formation of the Lunar Fossil Bulges and Its Implication for the Early Earth and Moon
Authors: Qin Chuan , Zhong Shijie , Phillips Roger 
Published: January 2018

AbstractFirst recognized by Laplace over two centuries ago, the Moon's present tidal‐rotational bulges are significantly larger than hydrostatic predictions. They are likely relics of a former hydrostatic state when the Moon was closer to the Earth and had larger bulges, and they were established when stresses in a thickening lunar lithosphere could maintain the bulges against hydrostatic adjustment. We formulate the first dynamically self‐consistent model of this process and show that bulge formation is controlled by the relative timing of lithosphere thickening and lunar orbit recession. Viable solutions indicate that lunar bulge formation was a geologically slow process lasting several hundred million years, that the process was complete about 4 Ga when the Moon‐Earth distance was less than ~32 Earth radii, and that the Earth in Hadean was significantly less dissipative to lunar tides than during the last 4 Gyr, possibly implying a frozen hydrosphere due to the fainter young Sun.
Prompt Disappearance and Emergence of Radiation Belt Magnetosonic Waves Induced by Solar Wind Dynamic Pressure Variations
Authors: Liu Nigang , Su Zhenpeng , Zheng Huinan , Wang Yuming , Wang Shui 
Published: January 2018

AbstractMagnetosonic waves are highly oblique whistler mode emissions transferring energy from the ring current protons to the radiation belt electrons in the inner magnetosphere. Here we present the first report of prompt disappearance and emergence of magnetosonic waves induced by the solar wind dynamic pressure variations. The solar wind dynamic pressure reduction caused the magnetosphere expansion, adiabatically decelerated the ring current protons for the Bernstein mode instability, and produced the prompt disappearance of magnetosonic waves. On the contrary, because of the adiabatic acceleration of the ring current protons by the solar wind dynamic pressure enhancement, magnetosonic waves emerged suddenly. In the absence of impulsive injections of hot protons, magnetosonic waves were observable even only during the time period with the enhanced solar wind dynamic pressure. Our results demonstrate that the solar wind dynamic pressure is an essential parameter for modeling of magnetosonic waves and their effect on the radiation belt electrons.
Bed Load Variability and Morphology of Gravel Bed Rivers Subject to Unsteady Flow: A Laboratory Investigation
Authors: Redolfi M. , Bertoldi W. , Tubino M. , Welber M. 
Published: January 2018

AbstractMeasurement and estimation of bed load transport in gravel bed rivers are highly affected by its temporal fluctuations. Such variability is primarily driven by the flow regime but is also associated with a variety of inherent channel processes, such as flow turbulence, grain entrainment, and bed forms migration. These internal and external controls often act at comparable time scales, and are therefore difficult to disentangle, thus hindering the study of bed load variability under unsteady flow regime. In this paper, we report on laboratory experiments performed in a large, mobile bed flume where typical hydromorphological conditions of gravel bed rivers were reproduced. Data from a large number of replicated runs, including triangular and square‐wave hydrographs, were used to build a statistically sound description of sediment transport processes. We found that the inherent variability of bed load flux strongly depends on the sampling interval, and it is significantly higher in complex, wandering or braided channels. This variability can be filtered out by computing the mean response over the experimental replicates, which allows us to highlight two distinctive phenomena: (i) an overshooting (undershooting) response of the mean bed load flux to a sudden increase (decrease) of discharge, and (ii) a clockwise hysteresis in the sediment rating curve. We then provide an interpretation of these findings through a conceptual mathematical model, showing how both phenomena are associated with a lagging morphological adaptation to unsteady flow. Overall, this work provides basic information for evaluating, monitoring, and managing gravel transport in morphologically active rivers.
Structured Goal Planning and Supportive Telephone Follow‐up in Rheumatology Care: Results From a Pragmatic, Stepped‐Wedge, Cluster‐Randomized Trial
Authors: Berdal Gunnhild , Bø Ingvild , Dager Turid N. , Dingsør Anne , Eppeland Siv G. , Hagfors Jon , Hamnes Bente , Mowinckel Petter , Nielsen Merete , Sand‐Svartrud Anne‐Lene , Slungaard Bente , Wigers Sigrid H. , Hagen Kåre B. , Dagfinrud Hanne S. , Kjeken Ingvild 
Published: January 2018

ObjectiveTo evaluate patient‐reported health effects of an add‐on structured goal‐planning and supportive telephone follow‐up rehabilitation program compared with traditional rehabilitation programs in patients with rheumatic diseases.MethodsIn this pragmatic stepped‐wedge, cluster‐randomized, controlled trial, 389 patients with rheumatic diseases recruited from 6 rehabilitation centers received either traditional rehabilitation or traditional rehabilitation extended with an add‐on program tailored to individual needs. The add‐on program comprised a self‐management booklet, motivational interviewing in structured individualized goal planning, and 4 supportive follow‐up phone calls after discharge. Data were collected by questionnaires on admission and discharge from rehabilitation stay, and at 6 months and 12 months after discharge. The primary outcome was health‐related quality of life (HRQoL) measured by the Patient Generated Index (range 0–100, where 0 = low). Secondary outcomes included patient‐reported health status, self‐efficacy, pain, fatigue, global disease activity, and motivation for change. The main statistical analysis was a linear repeated measures mixed model performed on the intent‐to‐treat population using all available data.ResultsA significant treatment effect of the add‐on intervention on HRQoL was found on discharge (mean difference 3.32 [95% confidence interval 0.27, 6.37]; P = 0.03). No significant between‐group differences were found after 6 or 12 months. Both groups showed positive changes in HRQoL following rehabilitation, which gradually declined, although the values remained at higher levels after 6 and 12 months compared with baseline values.ConclusionThe add‐on program enhanced the short‐term effect of rehabilitation with respect to patient‐specific HRQoL, but it did not prolong the effect as intended.
New Layered Triazine Framework/Exfoliated 2D Polymer with Superior Sodium‐Storage Properties
Authors: Liu Jingjing , Lyu Pengbo , Zhang Yu , Nachtigall Petr , Xu Yuxi 
Published: January 2018

AbstractThe efficient synthesis of 2D polymers (2DPs) with tailorable structures and properties is highly desired but remains a considerable challenge. Here, the first solution synthesis of millimeter‐size crystalline covalent triazine frameworks (CTFs) with a clear lamellar structure, which can be exfoliated into micrometer‐size few‐layer 2DP sheets via both micromechanical cleavage and liquid sonication, is reported. The obtained CTFs or 2DPs show a unique staggered AB stacking with a dominant pore size of ≈0.6 nm, which is different from the common eclipsed AA stacking in various covalent organic frameworks. The preference for AB stacking is due to the specific interaction of triflic acid with CTFs as revealed computationally. When explored as new polymeric anodes for sodium‐ion batteries, both crystalline bulk CTF and exfoliated 2DP exhibit very high capacities (225 and 262 mA h g−1 at 0.1 A g−1, respectively), impressive rate capabilities (67 and 119 mA h g−1 at 5.0 A g−1, respectively), and excellent cycling stability (95% capacity retention after 1200 cycles) due to their robust conjugated porous structure, outperforming most organic/polymeric sodium‐ion battery anodes ever reported.
Cosensitized Quantum Dot Solar Cells with Conversion Efficiency over 12%
Authors: Wang Wei , Feng Wenliang , Du Jun , Xue Weinan , Zhang Linlin , Zhao Leilei , Li Yan , Zhong Xinhua 
Published: January 2018

AbstractThe improvement of sunlight utilization is a fundamental approach for the construction of high‐efficiency quantum‐dot‐based solar cells (QDSCs). To boost light harvesting, cosensitized photoanodes are fabricated in this work by a sequential deposition of presynthesized Zn–Cu–In–Se (ZCISe) and CdSe quantum dots (QDs) on mesoporous TiO2 films via the control of the interactions between QDs and TiO2 films using 3‐mercaptopropionic acid bifunctional linkers. By the synergistic effect of ZCISe‐alloyed QDs with a wide light absorption range and CdSe QDs with a high extinction coefficient, the incident photon‐to‐electron conversion efficiency is significantly improved over single QD‐based QDSCs. It is found that the performance of cosensitized photoanodes can be optimized by adjusting the size of CdSe QDs introduced. In combination with titanium mesh supported mesoporous carbon as a counterelectrode and a modified polysulfide solution as an electrolyte, a champion power conversion efficiency up to 12.75% (Voc = 0.752 V, Jsc = 27.39 mA cm−2, FF = 0.619) is achieved, which is, as far as it is known, the highest efficiency for liquid‐junction QD‐based solar cells reported.
Palladium‐Catalyzed Regioselective Aerobic Allylic C−H Oxygenation: Direct Synthesis of α,β‐Unsaturated Aldehydes and Allylic Alcohols
Authors: Li Chunsheng , Chen Huoji , Li Jianxiao , Li Meng , Liao Jianhua , Wu Wanqing , Jiang Huanfeng 
Published: January 2018

AbstractA protocol for the synthesis of α,β‐unsaturated aldehydes and allylic alcohols from simple allylic hydrocarbons with water via palladium‐catalyzed functionalization of allylic C−H bonds was described. Molecular oxygen is utilized as the sole oxidant in this oxygenation of terminal alkenes. This protocol features good functional group compatibility, broad substrate scope, and high atom‐ and step‐economy. Moreover, the synthetic utility of this method can be highlighted by its application to the synthesis of ibuprofen, which is a highly potent analgesic.magnified image
Hierarchically Porous Network‐Like Ni/Co3O4: Noble Metal‐Free Catalysts for Carbon Dioxide Methanation
Authors: Wang Yuan , Arandiyan Hamidreza , Scott Jason , Dai Hongxing , Amal Rose 
Published: January 2018

AbstractThe impasse always present regarding catalysts for energy conversion reactions is that noble metals with promising activity are limited by their high price and scarcity, whereas base metals with a lower price show moderate activity performance. Herein, a purely transition metal‐based, Ni‐promoted 3D draped porous Co3O4 (Ni/3DDP‐Co3O4) catalyst is demonstrated to be highly effective for CO2 methanation, achieving 100% CO2 conversion and CH4 selectivity at 250 °C and a space velocity of 48 000 mL (g h)−1. Dispersing Ni nanodeposits on the large surface of the 3DDP‐Co3O4 promotes a 2.6 times increase in reaction rate and a 20% drop in apparent activation energy relative to 3DDP‐Co3O4. An abundance of surface oxygen vacancies extrinsically forms on the Ni/3DDP‐Co3O4 by both Co–Ni charge‐compensating mechanisms and hydrogen treatment, in conjunction with the low‐temperature reducibility, high surface area, and strong Co–Ni interaction effect, enabling the enhanced catalytic performance for CO2 methanation.
Capacitor‐Integrated Triboelectric Nanogenerator Based on Metal–Metal Contact for Current Amplification
Authors: Chung Jihoon , Yong Hyungseok , Moon Haksung , Choi Seung Tae , Bhatia Divij , Choi Dukhyun , Kim Dongseob , Lee Sangmin 
Published: January 2018

AbstractThe electrical power of triboelectric nanogenerators (TENGs) is increased by surface modifications, and they can successfully power portable devices alone. However, modifying the material and its surface may limit the device lifetime, and most of the portable applications demonstrated in previous studies have excessive input conditions. In this study, a capacitor‐integrated TENG (CI‐TENG) that uses the fundamental mechanisms of the Leyden jar is developed. In this device, a long sheet metal (capacitor electrode)–polymer–metal composite (TENG electrode) is rolled inside the casing cylinder, and a capacitor unit is fabricated at the end of the sheet composite. This new operating mechanism of the CI‐TENG is analyzed in terms of the dielectric constant of the capacitor unit and the metal‐to‐metal contact between electrodes. By instantaneous charging and discharging of the capacitor unit inside the CI‐TENG, it can generate a peak open‐circuit voltage of 156 V and a peak closed‐circuit current of 4.3 mA under manual input. It charges a capacitor more than three times faster than a conventional TENG does. Furthermore, the internal impedance of the CI‐TENG is decreased to 200 kΩ without any external circuit.
Accelerating Population Transfer in a Transmon Qutrit Via Shortcuts to Adiabaticity
Authors: Chen Ye‐Hong , Shi Zhi‐Cheng , Song Jie , Xia Yan , Zheng Shi‐Biao 
Published: January 2018

AbstractIn this paper, a method to accelerate population transfer by designing nonadiabatic evolution paths is proposed. We apply the method to realize robust and accelerated population transfer with a transmon qutrit. By numerical simulation, we show that this method allows a robust population transfer between the ground states in a Λ system. Moreover, the total pulse area for the population transfer is low as 1.9π that verifies the evolution is accelerated without increasing the pulse intensity. Therefore, the method is easily implementable based on the modern pulse shaper technology and it provides selectable schemes with interesting applications in quantum information processing.
Moderne Aspekte der Elektrochemie zur Synthese hochwertiger organischer Produkte
Authors: Möhle Sabine , Zirbes Michael , Rodrigo Eduardo , Gieshoff Tile , Wiebe Anton , Waldvogel Siegfried R. 
Published: January 2018

AbstractDie stoffliche Nutzung von Elektrizität anstelle stöchiometrischer Mengen an Oxidations‐ oder Reduktionsmitteln ist ökonomisch und ökologisch sehr attraktiv und stellt eine wichtige Triebkraft für die Forschungen in der Elektrosynthese dar. Um den Elektronentransfer an der Elektrode für eine organische Umsetzung zu nutzen, müssen die intermediär gebildeten Radikalspezies stabilisiert werden. Die Kombination der Elektrosynthese mit anderen Ansätzen der organischen Chemie oder aktuellen Synthesekonzepten ermöglicht die Entwicklung effizienter Synthesewege. Die zentrale Aufgabe des 21. Jahrhunderts besteht darin, möglichst wenig fossilen Kohlenstoff zu verwenden, weshalb die Nutzung erneuerbarer Energien immer wichtiger wird. Von steigendem Interesse ist auch die direkte Umsetzung erneuerbarer Rohstoffe, die zuvor hauptsächlich verbrannt wurden. Dieser Aufsatz gibt einen Überblick über viele der wichtigsten, zukunftsweisenden Entwicklungen der letzten Zeit, welche die Zukunft dieses sich rasch entwickelnden Feldes bestimmen werden.
Bioorthogonal Catalytic Activation of Platinum and Ruthenium Anticancer Complexes by FAD and Flavoproteins
Authors: Alonso‐de Castro Silvia , Cortajarena Aitziber L. , López‐Gallego Fernando , Salassa Luca 
Published: January 2018

AbstractRecent advances in bioorthogonal catalysis promise to deliver new chemical tools for performing chemoselective transformations in complex biological environments. Herein, we report how FAD (flavin adenine dinucleotide), FMN (flavin mononucleotide), and four flavoproteins act as unconventional photocatalysts capable of converting PtIV and RuII complexes into potentially toxic PtII or RuII−OH2 species. In the presence of electron donors and low doses of visible light, the flavoproteins mini singlet oxygen generator (miniSOG) and NADH oxidase (NOX) catalytically activate PtIV prodrugs with bioorthogonal selectivity. In the presence of NADH, NOX catalyzes PtIV activation in the dark as well, indicating for the first time that flavoenzymes may contribute to initiating the activity of PtIV chemotherapeutic agents.
Phosphine‐Catalyzed anti‐Carboboration of Alkynoates with 9‐BBN‐Based 1,1‐Diborylalkanes: Synthesis and Use of Multisubstituted γ‐Borylallylboranes
Authors: Yamazaki Ayaka , Nagao Kazunori , Iwai Tomohiro , Ohmiya Hirohisa , Sawamura Masaya 
Published: January 2018

AbstractTrialkylphosphine organocatalysis has enabled the regioselective anti‐carboboration of alkynoates with 9‐BBN‐based 1,1‐diborylalkanes to produce secondary allylboranes with β‐alkoxycarbonyl and γ‐boryl substituents. The utility of the densely functionalized allylboranes was demonstrated by the highly diastereoselective allylation of N‐(trimethylsilyl)aldimines to produce homoallylamines containing tertiary allylborane and acrylate moieties.
Rhodium(I)‐Catalyzed Cycloisomerization of Homopropargylallene‐Alkynes through C(sp3)−C(sp) Bond Activation
Authors: Kawaguchi Yasuaki , Yabushita Kenya , Mukai Chisato 
Published: January 2018

AbstractUpon exposure to a catalytic amount of [RhCl(CO)2]2 in 1,4‐dioxane, homopropargylallene‐alkynes underwent a novel cycloisomerization accompanied by the migration of the alkyne moiety of the homopropargyl functional group to produce six/five/five tricyclic compounds in good yields. A plausible mechanism was proposed on the basis of an experiment with 13C‐labeled substrate. The resulting tricyclic derivatives were further converted into the corresponding bicyclo[3.3.0] skeletons with vicinal cis dihydroxy groups.
Rhodium(I)‐Catalyzed Carboacylation/Aromatization Cascade Initiated by Regioselective C−C Activation of Benzocyclobutenones
Authors: Sun Tianwen , Zhang Yuna , Qiu Bo , Wang Yafei , Qin Yuting , Dong Guangbin , Xu Tao 
Published: January 2018

AbstractDescribed here is the first example of a rhodium‐catalyzed carboacylation/aromatization cascade of a C=O bond by C−C activation. In this transformation, a reactive rhodaindanone complex is regioselectively generated and adds across a C=O bond with subsequent elimination, thus providing a unique strategy to access a multisubstituted benzofuran scaffold. A diverse range of benzofuran analogues were obtained in good yields. Mechanistic studies show a tricyclic lactone was a viable intermediate. Application of this methodology to the total synthesis of C13‐deOH‐viniferifuran and C13‐deOH‐diptoindonesin G was achieved.
Hybrid of bamboo charcoal and silica by tetraethoxysilane hydrolysis over acid catalyst reinforced styrene‐butadiene rubber
Authors: Li Qingyuan , Li Xiangxu , Lee Dam‐Hee , Fan Yuan , Nam Byeong‐Uk , Lee Jong‐Eun , Cho Ur‐Ryong 
Published: January 2018

ABSTRACTThe hybrid of bamboo charcoal (BCC) and silica‐reinforced styrene‐butadiene rubber was prepared by a modified sol–gel method of hydrolyzing tetraethoxysilane over an acid catalyst. The fracture surface of the samples after tensile test was characterized by field emission‐scanning electron microscopy. The tensile strength, storage modulus, hardness, friction coefficient, and swelling test were discussed based on the samples with or without 3‐(methacryloxy) propyl trimethoxy silane modification. The results showed that the storage modulus clearly increased with the increasing of silica contents among the hybrid of BCC and silica‐reinforced samples. The storage modulus of the sample decreased after modification by 3‐(methacryloxy) propyl trimethoxy silane, indicating the improvement of the filler in SBR matrix. The tensile stress and the hardness both increased with the increasing of silica contents in the SBR matrix. Besides, the friction coefficient and the swelling ratio for the hybrid of BCC and silica‐reinforced SBR decreased with the decreasing of BCC contents in SBR matrix. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46219.
Highly Sensitive Bioluminescent Probe for Thiol Detection in Living Cells
Authors: Hemmi Mayu , Ikeda Yuma , Shindo Yutaka , Nakajima Takahiro , Nishiyama Shigeru , Oka Kotaro , Sato Moritoshi , Hiruta Yuki , Citterio Daniel , Suzuki Koji 
Published: January 2018

AbstractThe sensitive detection of thiols including glutathione and cysteine is desirable owing to their roles as indispensable biomolecules in maintaining intracellular biological redox homeostasis. Herein, we report the design and synthesis of SEluc‐1 (sulfinate ester luciferin), a chemoselective probe exhibiting a ratiometric and turn‐on response towards thiols selectively in fluorescence and bioluminescence, respectively. The probe, which was designed based on the “caged” luciferin strategy, displays excellent selectivity, high signal/noise ratio (>240 in the case of bioluminescence), and a biologically relevant limit of detection (LOD, 80 nm for cysteine), which are all desirable traits for a sensitive bioluminescent sensor. SEluc‐1 was further applied to fluorescence imaging of thiol activity in living human cervical cancer HeLa cell cultures, and was successfully able to detect fluctuations in thiol concentrations induced by oxidative stress in a bioluminescent assay utilizing African green monkey fibroblast COS‐7 cells and human breast adenocarcinoma MCF‐7 cells.