bluuebunny/crossref_metadata_2025_split huggingface dataset:
Uniformly Confined Germanium Quantum Dots in 3D Ordered Porous Carbon Framework for High‐Performance Li‐ion Battery
Authors: Wang Yan , Luo Sainan , Chen Min , Wu Limin 
Published: February 2020

AbstractAlthough abundant germanium (Ge)‐based anode materials have been explored to obtain high specific capacity, high rate performance, and long charge/discharge lifespans for lithium‐ion batteries (LIBs), their performances are still far from satisfactory due to the intrinsic defects of Ge and the relatively intricate anode structure. To work out these issues, a 3D ordered porous N‐doped carbon framework with Ge quantum dots uniformly embedded (3DOP Ge@NC) as a binder‐free anode for LIBs via a facile polystyrene colloidal nanospheres template‐confined strategy is proposed. This unique structure not only facilitates Li‐ion diffusion and electron transport that can guarantee rapid de/alloying reaction, but also alleviates the huge volume changes during reactions and improves cycling stability. Notably, the resulting anode delivers a high specific reversible capacity (≈1160 mA h g−1 at 1 A g−1), superior rate properties (exceeding 500 mA h g−1 at 40 A g−1), and excellent cycling stability (over 90% capacity retention after 1200 cycles even at 5 A g−1). Furthermore, both the 3DOP Ge@NC anode with high areal mass loading (up to 8 mg cm−2) and the full cell coupled with LiFePO4 cathode display high capacity and cycling stability, further indicative of the favorable real‐life application prospects for high‐energy LIBs.
Ag Nanoparticles Cluster with pH‐Triggered Reassembly in Targeting Antimicrobial Applications
Authors: Xie Xianli , Sun TianCi , Xue Jingzhe , Miao Zhaohua , Yan Xu , Fang WeiWei , Li Qing , Tang Rupei , Lu Yang , Tang Longxiang , Zha Zhengbao , He Tao 
Published: February 2020

AbstractAntibacterial efficiency can be effectively improved by applying targeting antibacterial materials and strategies. Herein, the successful synthesis of uniform pH‐responsive Ag nanoparticle clusters (AgNCs) is demonstrated, which can collapse and reassemble into nonuniform Ag NPs upon exposure to the acidic microenvironment of bacterial infections. This pH triggered reassembly contributes greatly to the improved antibacterial activities of AgNCs against both methicillin‐resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli). The minimum inhibitory concentration and minimum bactericidal concentration against MRSA are as low as 4 and 32 µg mL−1 (which are 8 and 32 µg mL−1 for E. coli), respectively. In vivo skin wound healing experiments confirm AgNCs can serve as an effective wound dressing to accelerate the healing of MRSA infection. The development of responsive AgNCs offers new materials and strategies in targeting antibacterial applications.
Cellulose Nanofibril Hydrogel Promotes Hepatic Differentiation of Human Liver Organoids
Authors: Krüger Melanie , Oosterhoff Loes A. , van Wolferen Monique E. , Schiele Simon A. , Walther Andreas , Geijsen Niels , De Laporte Laura , van der Laan Luc J. W. , Kock Linda M. , Spee Bart 
Published: February 2020

AbstractTo replicate functional liver tissue in vitro for drug testing or transplantation, 3D tissue engineering requires representative cell models as well as scaffolds that not only promote tissue production but also are applicable in a clinical setting. Recently, adult liver‐derived liver organoids are found to be of much interest due to their genetic stability, expansion potential, and ability to differentiate toward a hepatocyte‐like fate. The current standard for culturing these organoids is a basement membrane hydrogel like Matrigel (MG), which is derived from murine tumor material and apart from its variability and high costs, possesses an undefined composition and is therefore not clinically applicable. Here, a cellulose nanofibril (CNF) hydrogel is investigated with regard to its potential to serve as an alternative clinical grade scaffold to differentiate liver organoids. The results show that its mechanical properties are suitable for differentiation with overall, either equal or improved, functionality of the hepatocyte‐like cells compared to MG. Therefore, and because of its defined and tunable chemical definition, the CNF hydrogel presents a viable alternative to MG for liver tissue engineering with the option for clinical use.
Atomic Doping and Anion Reconstructed CoF2 Electrocatalyst for Oxygen Evolution Reaction
Authors: Dong Qiuchun , Su Tingting , Ge Wei , Ren Yanfang , Liu Yunlong , Wang Wenjun , Wang Qian , Dong Xiaochen 
Published: February 2020

AbstractElectrocatalytic water splitting is one of the most promising green solutions for large‐scale hydrogen production, which has developed rapidly in recent years. The slow reaction rate of oxygen evolution reaction (OER) has become the bottleneck to improve the electrocatalytic efficiency. Herein, Fe‐doped CoF2 nanowire arrays on 3D nickel foam are prepared by two steps of hydrothermal reaction and fluorination process. The increased catalytic activity sites and accelerated charge transfer rate make the self‐supported Fe‐doped CoF2 electrode show excellent OER performance in alkaline electrolyte. An overpotential of 230 mV is only required to release a current density of 10 mA cm−2. The Tafel slope derived from the polarization curves is 59 mV dec−1, indicating outstanding electrochemical kinetics performance. A stable output current density of 84 mA cm−2 for more than 96 h is achieved under an invariant overpotential of 338 mV, attributing to the anion reconstruction making part of CoF2 transform into cobalt hydroxide and further improving its electrocatalytic performance.
Scanning Nanowire Probe Interferometer for Scalable Humidity Mapping
Authors: Kim Namho , Lee Junho , Yong Moon‐Jung , Yang Un , Kim Ji Tae , Kim Jonghwan , Weon Byung Mook , Kim Chong Cook , Je Jung Ho 
Published: February 2020

AbstractQuantifying humidity has long been an unavoidable task in science, industry, and society. Recent developments of nanoscience and technology that deal with ultrasmall droplets have aroused interest in microscopic moisture. Utilization of nanomaterials has been emerging as a promising strategy to miniaturize hygrometers for high‐sensitive, ultrasmall‐area sensing. However, a lack of high‐precision, on‐demand position control of sensing nanomaterials makes it difficult to explore spatial distribution of humidity at the micro‐ and nanoscale. Here, a scanning probe hygrometry (SPH) is developed that enables not only micro/nanoresolution but also scalable spatial mapping of humidity distribution. The SPH is realized with an unprecedented scanning nanowire probe interferometer (NPI) that is produced by direct 3D nanoprinting of a moisture‐sensitive polymer on a tapered optical fiber. Notably, the interferometric response of the NPI probe in ultrasmall areas quantitatively depends on humidity, arising from its refractive index change and volumetric swelling. By scanning the NPI probe and reading out the interferometric signals, multiscale spatial mapping of humidity distribution with versatile scanning steps from ≈102 nm to a few mm is demonstrated. The NPI is expected to provide a new nanoscale metrology that can answer fundamental questions about evaporation‐related science and engineering.
Sensitive and Fast Direct Conversion X‐Ray Detectors Based on Single‐Crystalline HgI2 Photoconductor and ZnO Nanowire Vacuum Diode
Authors: Zhang Zhipeng , Zhang Zhaojun , Zheng Wei , Wang Kai , Chen Huanjun , Deng Shaozhi , Huang Feng , Chen Jun 
Published: February 2020

AbstractPhotoconductive cold cathode X‐ray detectors are highly promising for use in medical diagnosis, industrial inspection, and scientific research applications. However, development of highly sensitive, fast, and stable direct conversion X‐ray detectors remains very challenging because of structural and material limitations. This article presents a direct conversion X‐ray detector based on a HgI2 crystal and a ZnO nanowire vacuum diode with sensitivity of 6.8 × 103 µCGyair−1 cm−2, which is nearly two orders of magnitude higher than that of a commercial a‐Se X‐ray detector. The X‐ray detector, which uses a high‐crystallization HgI2 photoconductor, shows a response time of 0.24 ms, thus significantly outperforming the polycrystalline HgI2 X‐ray detector. In addition, the current limitation between the HgI2 photoconductor and the ZnO nanowire cold cathodes guaranteed device reliability under high applied electric fields for practical applications. The findings presented in this work demonstrate that the proposed X‐ray detector based on the HgI2 photoconductor and the ZnO nanowire vacuum diode is highly efficient and stable.
Indirekte und direkte Anknüpfung von Übergangsmetallen an Silicoide
Authors: Poitiers Nadine E. , Giarrana Luisa , Leszczyńska Kinga I. , Huch Volker , Zimmer Michael , Scheschkewitz David 
Published: February 2020

AbstractUngesättigte, ladungsneutrale Siliciumcluster (Silicoide) sind wichtige Zwischenprodukte bei der Gasphasenabscheidung an der Grenze zwischen Molekülen und Materialien. Mit den stabilen Zirconocen‐ und Hafnocensubstituierten Derivaten berichten wir nun über die ersten Beispiele mit direkt gebundenen Übergangsmetallfragmenten, die aus dem ligato‐lithiierten Si6‐Silicoid (1Li) und Cp2MCl2 (M=Zr, Hf) leicht zugängig sind. Ladungsneutrale Silicoidliganden mit angehängter Tetrylenfunktionalität werden durch die Umsetzung von 1Li mit Amidinato‐Chlortetrylenen (PhC(NtBu)2ECl (E=Si, Ge, Sn) erhalten, was zudem die prinzipielle Kompatibilität solcher niedervalenter Funktionalitäten mit dem ungesättigten Si6‐Clustergerüst beweist. Die ausgeprägten Donoreigenschaften der Tetrylen/Silicoid‐Hybride ermöglichen deren Koordination an das Fe(CO)4‐Fragment.
High energy storage capacitance of defluorinated polyvinylidene fluoride and polyvinylidene fluoride blend alloy for capacitor applications
Authors: Lu Hongwei , Du Jianxin , Zhang Huilong , Guo Xiaojie , Du Jiayou , Zhang Yishan , Li Chenxiang , Dong Linxi , Chen Yingxin 
Published: February 2020

AbstractWith the development of high energy density and high dielectric materials, the potential applications in modern microelectronics and power systems are receiving more and more attention. It has been found herein that the elimination reaction can occur by placing polyvinylidene fluoride (PVDF) in an aqueous solution of polyvinylpyrrolidone (PVP) and potassium hydroxide. Moreover, the combination of dehydrofluorinated polyvinylidene fluoride (MD‐PVDF) and untreated PVDF can efficiently increase the dielectric constant and the storage density. When the content of MD‐PVDF reaches 5%, the storage density is the largest, that is, at the field strength of 400 MV m−1, the storage density can reach 12 J cm−3. This work provides a novel approach to improve the energy storage performance of polymer dielectrics.
Knocking down the sex peptide receptor by dsRNA feeding results in reduced oviposition rate in olive fruit flies
Authors: Gregoriou Maria‐Eleni , Mathiopoulos Kostas D. 
Published: February 2020

AbstractInsect pests can cause crop damage in yield or quality, resulting in profit losses for farmers. The primary approach to control them is still the use of chemical pesticides resulting in significant hazards to the environment and human health. Biological control and the sterile insect technique are alternative strategies to improve agriculture protection. However, both strategies have significant limitations. A newly introduced approach that could be both effective and species‐specific is the RNA interference mechanism. One key point for the success of this strategy is the delivery method of double‐strand RNA (dsRNA) to the insects. A method of dsRNA delivery to insects with potential use in the field is the oral delivery, feeding the insects engineered microorganisms that produce dsRNA. Here, we present the first protocol for dsRNA feeding using modified bacteria, in the olive fruit fly, the most important insect pest of cultivated olives. We chose to target the sex peptide receptor gene. The sex peptide receptor interacts with the sex peptide, a peptide that is responsible for the postmating behavior in the model organism, Drosophila melanogaster. Feeding the female olive fruit fly with bacteria that produced dsRNA for the sex peptide receptor gene resulted in the development of female insects with significantly lower oviposition rates. Administration of dsRNA producing bacteria in insect diet against target genes that lead to genetic sexing or female‐specific lethality could be added in the armory of control methods.
Association Between Race and Radiographic, Symptomatic, and Clinical Hand Osteoarthritis: A Propensity Score–Matched Study Using Osteoarthritis Initiative Data
Authors: Pishgar Farhad , Kwee Robert M. , Haj‐Mirzaian Arya , Guermazi Ali , Haugen Ida K. , Demehri Shadpour 
Published: February 2020

ObjectiveTo determine the associations between Black race and the presence of radiographic, symptomatic, and clinical hand osteoarthritis (OA).MethodsUsing available hand radiographs from the Osteoarthritis Initiative cohort (total 4,699; n = 849 Black subjects [18.1%], n = 3,850 non‐Black subjects [81.9%]), a propensity score–matching method was used to match Black subjects with non‐Black subjects for known potential risk factors of hand OA (age, sex, body mass index, smoking status, cardiovascular disease, osteoporosis, excessive occupation‐ or recreation‐related hand use, and knee OA). Posteroanterior radiographs of subjects’ dominant hands were reviewed by a musculoskeletal radiologist in a blinded manner. To assess the severity of hand OA, the modified Kellgren/Lawrence (K/L) radiographic OA scoring scale (grades 0–4) was used, and the presence of erosive OA in the hand joints was recorded. Associations between race and the severity of hand OA (measured as the summed modified K/L grade), presence of radiographic hand OA (modified K/L grade ≥2), presence of erosive hand OA, presence of symptomatic hand OA (radiographic OA with hand pain), and presence of clinical hand OA (indicated by clinical findings of Heberden's nodes in the hands) were studied using regression models. In these models, beta coefficients or odds ratios (ORs) with 95% confidence intervals (95% CIs) were calculated for the associations between Black race and any of these radiographic and symptomatic hand OA phenotypes.ResultsBlack subjects had less severe hand OA (β = –1.93 [95% CI –2.53, –1.34]), as well as a lower risk of developing radiographic hand OA (OR 0.79 [95% CI 0.66, 0.94]), erosive hand OA (OR 0.23 [95% CI 0.11, 0.47]), symptomatic hand OA (OR 0.63 [95% CI 0.49, 0.82]), and clinical hand OA (OR 0.49 [95% CI 0.41, 0.60]), as compared to non‐Black subjects.ConclusionIn contrast to the well‐established association between Black race and knee or hip OA, the findings of this study suggest that the risk of hand OA is lower in Black subjects compared to non‐Black subjects, which is not mediated by known hand OA risk factors. Future studies are warranted to determine the mediating protective factors for hand OA among Black subjects.
The stability of Twitter metrics: A study on unavailable Twitter mentions of scientific publications
Authors: Fang Zhichao , Dudek Jonathan , Costas Rodrigo 
Published: February 2020

AbstractThis study investigated the stability of Twitter counts of scientific publications over time. For this, we conducted an analysis of the availability statuses of over 2.6 million Twitter mentions received by the 1,154 most tweeted scientific publications recorded by Altmetric.com up to October 2017. The results show that of the Twitter mentions for these highly tweeted publications, about 14.3% had become unavailable by April 2019. Deletion of tweets by users is the main reason for unavailability, followed by suspension and protection of Twitter user accounts. This study proposes two measures for describing the Twitter dissemination structures of publications: Degree of Originality (i.e., the proportion of original tweets received by an article) and Degree of Concentration (i.e., the degree to which retweets concentrate on a single original tweet). Twitter metrics of publications with relatively low Degree of Originality and relatively high Degree of Concentration were observed to be at greater risk of becoming unstable due to the potential disappearance of their Twitter mentions. In light of these results, we emphasize the importance of paying attention to the potential risk of unstable Twitter counts, and the significance of identifying the different Twitter dissemination structures when studying the Twitter metrics of scientific publications.
Unexpected loss of sensitivity to the nicotinic acetylcholine receptor antagonist activity of mecamylamine and dihydro‐β‐erythroidine in nicotine‐tolerant mice
Authors: de Moura Fernando B. , Wilkerson Jenny L. , McMahon Lance R. 
Published: February 2020

AbstractObjectivesThere is a long‐standing interest in developing nicotinic acetylcholine receptor (nAChR) antagonists for concomitant use with nAChR agonists (e.g., nicotine replacement) as complementary smoking cessation aids. Previous studies demonstrate that daily nicotine treatment confers tolerance to some effects of nicotine, as well as cross‐tolerance to other nAChR agonists. The current study assessed the extent to which antagonism of nicotine varies as a function of daily nicotine treatment.MethodsSchedule‐controlled responding and hypothermia were selected for study because they have been previously used to examine the pharmacology of nicotine, and both are sensitive to the development nicotine tolerance. The rate‐decreasing and hypothermic effects of nicotine, as well as antagonism of those effects, were examined in C57BL/6J mice before, during treatment with, and after discontinuation of three daily injections of 1.78 mg/kg nicotine. The nonselective nAChR antagonist mecamylamine and the β2 nAChR antagonist dihydro‐β‐erythroidine (DHβE) were studied in combination with nicotine.ResultsThe ED50 values of nicotine to produce rate‐decreasing and hypothermic effects were, respectively, 0.44 and 0.82 mg/kg prior, 1.6 and 3.2 mg/kg during, and 0.74 and 1.1 mg/kg after discontinuation of daily nicotine treatment. Prior to daily nicotine treatment, mecamylamine decreased response rate and rectal temperature. However, during daily nicotine, mecamylamine (up to 5.6 mg/kg) only decreased rectal temperature. DHβE (up to 5.6 mg/kg) when studied prior to daily nicotine decreased rectal temperature, but that decrease was abolished during chronic nicotine treatment. Mecamylamine and DHβE antagonized the rate‐decreasing and hypothermic effects of nicotine before and after daily nicotine; however, during daily nicotine, mecamylamine and DHβE antagonized only the hypothermic effects of nicotine.ConclusionsThe differential antagonism of rate‐decreasing and hypothermic effects implicates differential involvement of nAChR subtypes. The decreased capacity of mecamylamine and DHβE to antagonize nicotine during chronic nicotine treatment may indicate that their effectiveness as smoking cessations might vary as a function of nicotine tolerance and dependence.
Entrepreneurial finance and new venture success ‐ the moderating role of government support
Authors: Anwar Muhammad , Tajeddini Kayhan , Ullah Rizwan 
Published: February 2020

AbstractThe high failure ratio in newly born ventures across the globe has been raised a challenging question. Numerous strategies have been introduced to enhance the survival of new ventures in the long run, but the results are fragmented. The research model examined the influence of entrepreneurial finance on new venture success. The model also considered a moderating role of government support while predicting ventures success. This area is under‐researched particularly in the context of Pakistan; therefore, this research may contribute to the existing body of knowledge to appraise the industry in Pakistan. Data were collected from 182 new ventures operating in an emerging economy in Pakistan and analyzed by SmartPLS. The results indicate that entrepreneurial finance and government support have a significant influence on new venture success. Moderation analysis demonstrates that government support strengthens the relationship between entrepreneurial finance and new venture success. The findings suggest implications for policymakers to initiate effective policies and programs for newly started ventures regarding financial and nonfinancial support; in this backdrop, the incubation services are important.
Spotlight on Large Surface Copper Cluster Role of Cu‐SAPO‐34 Catalyst in Standard NH3‐SCR Performances
Authors: Pétaud Guillaume , Gaillard François , Tayakout Melaz , Gil Sonia , Giroir‐Fendler Anne 
Published: February 2020

AbstractIn the present study, the catalytic role and behavior of different copper cluster configurations during NH3 SCR, NO and NH3 oxidation reactions will be studied in detail. For this purpose, two preparation methods were performed. The physico‐chemical and surface properties were characterized by different techniques, such as XRD, ICP, N2 ads/des, HR‐TEM, XPS, NMR, ex‐situ/in‐situ DRIFT, NH3 TPD and H2 TPR, in order to evaluate the impact of copper incorporation method on redox active sites, and, as a consequence, to better understand the mechanism of the NH3 SCR reaction.
Multiporous Carbon Encapsulated Ni Nanoparticles Promoting Glycerol Valorisation towards Hydrogenation against Rearrangement†
Authors: Zhang Bin , Chen Bin , Douthwaite Mark , Tang Lipeng , Zhang Yibo , Wang Meng , Ma Ding 
Published: February 2020

Summary of main observation and conclusionA dual‐templating method was used to synthesize a series of hierarchical carbon supports containing different proportions of spherical macropores (ca. 200 nm in diameter) and mesoporous channels (ca. 4 nm in diameter). These and some other conventional carbon materials were subsequently impregnated with Ni and tested for the conversion of glycerol. The hierarchical catalysts exhibited a significantly higher conversion (96%) and selectivity (77%) to 1,2‐propanediol, and the specificity selectivity coefficient (6.1) towards 1,2‐propanediol against lactic acid was three times higher than that observed over a conventional Ni/Cmicro catalyst (2.1). The enhanced performance of these materials, compared with the Ni nanoparticles supported on conventional carbon supports, was attributed to their high surface areas (> 1110 m2∙g−1) and large pore volumes (ca. 0.4 cm3∙g−1) permitting greater accessibility of substrate and/or intermediates to Ni active sites. Given that the concentration of accessible Ni sites in these materials is higher, a competitive benzilic‐acid‐rearrangement reaction to produce lactic acid was suppressed, leading to an enhanced hydrogenation selectivity to 1,2‐propanediol. This study evidences the potential benefits, which can be established from utilizing hierarchical support materials in the valorization of biomass.