bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adaptable Hydrogels Mediate Cofactor‐Assisted Activation of Biomarker‐Responsive Drug Delivery via Positive Feedback for Enhanced Tissue Regeneration
Authors: Zhang Kunyu , Jia Zhaofeng , Yang Boguang , Feng Qian , Xu Xiao , Yuan Weihao , Li Xingfu , Chen Xiaoyu , Duan Li , Wang Daping , Bian Liming 
Published: October 2018

AbstractThe targeted and simultaneous delivery of diverse cargoes with vastly different properties by the same vehicle is highly appealing but challenging. Here, a bioactive nanocomposite hydrogel based on hyaluronic acid and self‐assembled pamidronate‐magnesium nanoparticles for the localized elution and on‐demand simultaneous release of bioactive ions and small molecule drugs is described. The obtained nanocomposite hydrogels exhibit excellent injectability and efficient stress relaxation, thereby allowing easy injection and consequent adaptation of hydrogels to bone defects with irregular shapes. Magnesium ions released from the hydrogels promote osteogenic differentiation of the encapsulated human mesenchymal stem cells (hMSCs) and activation of alkaline phosphatase (ALP). The activated ALP subsequently catalyzes the dephosphorylation (activation) of Dex phosphate, a pro‐drug of Dex, and expedites the release of Dex from hydrogels to further promote hMSC osteogenesis. This positive feedback circuit governing the activation and release of Dex significantly enhances bone regeneration at the hydrogel implantation sites. The findings suggest that these injectable nanocomposite hydrogels mediate optimized release of diverse therapeutic cargoes and effectively promote in situ bone regeneration via minimally invasive procedures.
Umpolung of Carbonyl Groups as Alkyl Organometallic Reagent Surrogates for Palladium‐Catalyzed Allylic Alkylation
Authors: Zhu Dianhu , Lv Leiyang , Li Chen‐Chen , Ung Sosthene , Gao Jian , Li Chao‐Jun 
Published: October 2018

AbstractPalladium‐catalyzed allylic alkylation of nonstabilized carbon nucleophiles is difficult and remains a major challenge. Reported here is a highly chemo‐ and regioselective direct palladium‐catalyzed C‐allylation of hydrazones, generated from carbonyls, as a source of umpolung unstabilized alkyl carbanions and surrogates of alkyl organometallic reagents. Contrary to classical allylation techniques, this umpolung reaction utilizes hydrazones prepared not only from aryl aldehydes but also from alkyl aldehydes and ketones as renewable feedstocks. This strategy complements the palladium‐catalyzed coupling of unstabilized nucleophiles with allylic electrophiles by providing an efficient and selective catalytic alternative to the traditional use of highly reactive alkyl organometallic reagents.
Selective Degradation of Polo‐like Kinase 1 by a Hydrophobically Tagged Inhibitor of the Polo‐Box Domain
Authors: Rubner Stefan , Scharow Andrej , Schubert Sabine , Berg Thorsten 
Published: October 2018

AbstractHydrophobic tagging (HT) of bioactive compounds can induce target degradation via the proteasomal pathway. The first application of hydrophobic tagging to an existing inhibitor of protein–protein interactions is now presented. We developed Poloxin‐2HT by fusing an adamantyl tag to Poloxin‐2, an inhibitor of the polo‐box domain of the protein kinase Plk1, which is a target for tumor therapy. Poloxin‐2HT selectively reduced the protein levels of Plk1 in HeLa cells and had a significantly stronger effect on cell viability and the induction of apoptosis than the untagged PBD inhibitor Poloxin‐2. The change in cellular phenotype associated with the addition of the hydrophobic tag to Poloxin‐2 demonstrated that Poloxin‐2HT targets Plk1 in living cells. Our data validate hydrophobic tagging of selective inhibitors of protein–protein interactions as a novel strategy to target and destroy disease‐relevant proteins.
A Microstructured Graphene/Poly(N‐isopropylacrylamide) Membrane for Intelligent Solar Water Evaporation
Authors: Zhang Panpan , Liu Feng , Liao Qihua , Yao Houze , Geng Hongya , Cheng Huhu , Li Chun , Qu Liangti 
Published: October 2018

AbstractIntelligent solar water evaporation (iSWE) was achieved with a thermally responsive and microstructured graphene/poly(N‐isopropylacrylamide) (mG/PNIPAm) membrane. As the solar intensity varies, the water evaporation is tuned through reversible transformations of microstructures reminiscent of the stomatal opening and closing of leaves. Consequently, this mG/PNIPAm membrane displays a high water evaporation rate change (ΔWER) of 1.66 kg m−2 h−1 under weak sunlight (intensity<1 sun) and a low ΔWER of 0.24 kg m−2 h−1 under intense sunlight (1 sun<intensity<2 sun). Because of the double‐layer structure with predictable shape and dynamics, the leaf‐like membrane can further autonomously modulate the water evaporation by self‐curling under intense solar irradiation in accordance with simulation results. This mG/PNIPAm membrane provides a smart material platform with self‐adaptability in response to changing environments.
Bonding of Two 8‐Electron Superatom Clusters
Authors: Jin Shan , Zou Xuejuan , Xiong Lin , Du Wenjun , Wang Shuxin , Pei Yong , Zhu Manzhou 
Published: October 2018

AbstractWe report the observation of dimerization of two 8‐electron superatom cluster units in the crystallographic structures of Au2Ag42(SAdm)27(BPh4) and [Au2Ag48(S‐tBu)20(Dppm)6Br11]Br(BPh4)2 nanoclusters. The crystallographic analysis reveals that both nanoclusters have a Au2Ag24 core made of two separated icosahedral without sharing metal atoms, and each icosahedron has an eight‐electron (8e) closed shell (1S21P6). The valence electronic structures of these two nanoclusters are analogous to that of a Ne atom dimer (Ne2) according to the density functional theory (DFT) analysis. This is the first crystallographic observation of the dimerization of 8‐electron superatom units. This study enriches the fundamental knowledge on metal superatom clusters and implies the possibility for further assembling metal superatom building blocks into higher order superatom molecules.
Efficient Palladium‐Catalyzed Aerobic Arylative Carbocyclization of Enallenynes
Authors: Liu Jie , Ricke Alexander , Yang Bin , Bäckvall Jan‐E. 
Published: October 2018

AbstractHerein, we communicate a selective and efficient protocol for oxidative arylating carbocyclization of enallenynes using O2 as the oxidant. The key to success for this aerobic transformation is the application of a specific electron transfer mediator (ETM), a bifunctional catalyst consisting of a metal‐macrocycle and quinone moieties. This catalyst significantly facilitates the reoxidation of Pd0 to PdII under atmospheric pressure of O2. Diverse functionalized enallenynes react with aryl boronic acids to afford the corresponding cyclic tetraenes in moderate to good yields.
Innate Lymphoid Cells and T Cells Contribute to the Interleukin‐17A Signature Detected in the Synovial Fluid of Patients With Juvenile Idiopathic Arthritis
Authors: Rosser Elizabeth C. , Lom Hannah , Bending David , Duurland Chantal L. , Bajaj‐Elliott Mona , Wedderburn Lucy R. 
Published: October 2018

ObjectiveEvidence suggests that aberrant function of innate lymphoid cells (ILCs), whose functional and transcriptional profiles overlap with those of Th cell subsets, contributes to immune‐mediated pathologies. To date, analysis of juvenile idiopathic arthritis (JIA) immune pathology has concentrated on the contribution of CD4+ T cells; we have previously identified an expansion of Th17 cells within the synovial fluid (SF) of JIA patients. We undertook this study to extend this analysis to further investigate the role of ILCs and other interleukin‐17 (IL‐17)–producing T cell subsets in JIA.MethodsILCs and CD3+ T cell subsets were defined in peripheral blood mononuclear cells (PBMCs) from healthy adults, healthy children, and JIA patients and in SF mononuclear cells (SFMCs) from JIA patients using flow cytometry. Defined subsets in SFMCs were correlated with clinical measures including physician's global assessment of disease activity on a visual analog scale, number of joints with active disease, and erythrocyte sedimentation rate. Transcription factor and cytokine profiles of sorted ILCs were assessed by quantitative reverse transcriptase–polymerase chain reaction.ResultsGroup 1 ILCs (ILC1s), NKp44− group 3 ILCs (natural cytotoxicity receptor–negative [NCR−] ILC3s), and NKp44+ ILC3s (NCR+ ILC3s) were enriched in JIA SFMCs compared to PBMCs, which corresponded to an increase in transcripts for TBX21, IFNG, and IL17A. Of the ILC subsets, the frequency of NCR− ILC3s in JIA SFMCs displayed the strongest positive association with clinical measures, which was mirrored by an expansion in IL‐17A+CD4+, IL‐17A+CD8+, and IL‐17A+ γδ T cells.ConclusionWe demonstrate that the strength of the IL‐17A signature in JIA SFMCs is determined by multiple lymphoid cell types, including NCR− ILC3s and IL‐17A+CD4+, IL‐17A+CD8+, and IL‐17A+ γδ T cells. These observations may have important implications for the development of stratified therapeutics.
Recent Advances in Metal‐Organic Framework Derivatives as Oxygen Catalysts for Zinc‐Air Batteries
Authors: Zhong Yijun , Xu Xiaomin , Wang Wei , Shao Zongping 
Published: October 2018

AbstractElectrochemical energy storage systems with high power output, large energy density, and stable performance are urgently needed. Zn–air batteries are one of the most promising candidates owing to abundant and inexpensive resources used, decent energy density, and the high reduction potential of Zn. The most significant challenge of primary and rechargeable aqueous Zn‐air batteries is the relatively high overpotential due to the sluggish kinetics of oxygen reactions on the air cathode. Highly efficient oxygen catalysts derived from metal‐organic framework (MOF) precursors have demonstrated remarkable capabilities for facilitating the oxygen reactions. In this contribution, we review the recent progress in state‐of‐the‐art MOF‐derived materials for use as oxygen catalysts in primary and rechargeable Zn‐air batteries. We first summarize the development of several important MOF derivatives, including transition metal‐nitrogen‐carbon (TM−N−C) composites, carbon‐based transition metal compounds, and metal‐free carbons. The advantages and disadvantages of these MOF‐derived catalysts are also discussed. Strategies for optimization of the gas‐liquid diffusion and the long‐range electronic transportation on the air cathode with these MOF‐derived catalysts are also demonstrated. Finally, the main challenges and some perspectives for developing advanced MOF‐derived catalysts applied in Zn–air batteries are provided.
Design‐based inference on Bernstein type estimators for continuous populations
Authors: Franceschi Sara , Marcheselli Marzia , Naddeo Stefania , Pisani Caterina 
Published: October 2018

AbstractThe estimation of the values of a variable at any point of a study area is performed using Bernstein polynomials when the sampling scheme is implemented by selecting a point in each polygon of a regular grid overimposed onto the area. The evaluation of the precision of the resulting estimates is investigated under a completely design‐based framework. Moreover, as the main contribution to the mean squared error of the Bernstein‐type estimator is due to the bias, also a pseudo‐jackknife estimator is proposed. The performance of both estimators is investigated theoretically and by means of a simulation study. An application to a soil survey performed in Berkshire Downs in Oxfordshire (UK) is considered.
Correlation between Copper Oxide Particle Size and Selectivity towards Propylene Oxide in Selective Oxidation of Propene
Authors: Diekmann Marek , Koch Gregor , König Michaela , Ressler Thorsten 
Published: October 2018

AbstractCopper oxide catalysts supported on nanostructured silica SBA‐15 were synthesized with varying copper loadings in a range from 1.1 to 19.4 wt.%. Catalysts were structurally characterized by N2 physisorption, X‐ray diffraction and ex situ as well as in situ diffuse reflectance UV‐Vis spectroscopy. Copper oxide species contained Cu2+ in an octahedral configuration with a tetragonal distortion. Increasing the copper loading resulted in a decreasing optical band gap, which is associated with a growing particle size. Additionally, CuO/SBA‐15 samples were examined by temperature‐programmed reduction confirming a narrow particle size distribution. Structural evolution and catalytic activity were investigated during selective oxidation of propene focusing on product distribution of nucleophilic and electrophilic oxidation. Catalytic testing was carried out using an on‐line GC and MS coupled to a laboratory fixed‐bed reactor. All catalysts selectively oxidized propene to acrolein and propylene oxide (PO). With time on stream activity decreased while selectivity towards acrolein and PO increased. While selectivity towards PO increased with copper loading and, hence, copper oxide particle size, selectivity towards acrolein was largely independent of copper loading.
NiCo2O4@NiMoO4 Supported on Nickel Foam for Electrocatalytic Water Splitting
Authors: Du Xiaoqiang , Fu Jianpeng , Zhang Xiaoshuang 
Published: October 2018

AbstractSplitting water to make hydrogen is one of the most effective ways to solve the energy crisis. In this paper, we started with the catalysts of the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) of electrocatalytic water splitting, studied the catalysts with great stability and practicality, and designed NiCo2O4 nanowires as precursors, on whose surface we set NiMoO4 nanosheets. Cobalt elements were introduced on the nickel foam with electrocatalytic properties, and a flower‐like NiCo2O4@NiMoO4 core‐shell hybrid nanostructure was prepared by a hydrothermal method. The series of core‐shell nanocatalysts were characterized via XRD, SEM, XPS, etc. The electrochemical properties of the obtained catalysts were also measured, and the conclusion that the catalysts could reduce the overpotential of the reaction required was figured out. The conclusion of the overpotential of catalyzing the water splitting reaction provides new ideas for the research of the catalyst for electrocatalytic water splitting reaction.
Recent Advances in the Direct Synthesis of H2O2
Authors: Lewis Richard J. , Hutchings Graham J. 
Published: October 2018

AbstractHydrogen peroxide (H2O2) is a highly effective, green oxidant that has found application in sectors ranging from the synthesis of fine chemicals and waste stream treatment to the extraction of precious metals and the bleaching of paper pulp and textiles. The growing demand for H2O2 has seen it become one of the 100 most important chemicals in the world. The direct synthesis of H2O2 from H2 and O2 has been a challenge for the scientific community for over 100 years and represents an attractive alternative to the current means of production. Herein we discuss the historical perspective of the direct synthesis process, the recent literature regarding catalyst design and the role of additives as well as the application of H2O2 as an in situ oxidant. We discuss the key problems that remain and conclude that although there has been progress with respect to the selectivity of hydrogen utilisation, there is a need to now concentrate on catalyst activity as the key remaining problem requiring a solution is the concentration of H2O2 that can be achieved, especially in flow reactors.
Selective Removal of H2S from Gas Streams with High CO2 Concentration Using Hollow‐Fiber Membrane Contractors
Authors: Mirfendereski Seyed Mojtaba , Niazi Zahra , Mohammadi Toraj 
Published: October 2018

AbstractSelective and simultaneous separation of H2S and CO2 from CH4 was accomplished in a hollow‐fiber membrane contactor (HFMC). The absorption of both H2S and CO2 using an aqueous solution of methyldiethanolamine (MDEA) was almost complete and acid gases were totally removed. Despite the large difference between H2S and CO2 concentrations, the rate of H2S absorption was not significantly influenced by CO2 absorption. The independent effect and interactions of several process variables on the separation performance of H2S and CO2 were investigated. The results indicated that the membrane contactor could be a highly efficient choice for removal of almost all H2S in the presence of a large CO2 content even at high gas/liquid flow ratio. The selectivity of H2S was about three times higher compared to the conventional absorption packed towers.
Highly Sensitive and Selective Electrochemical Detection of Dopamine using Hybrid Bilayer Membranes
Authors: Patrice Fato T. , Zhao Li‐Jun , Fodjo Essy K. , Li Da‐Wei , Qiu Kaipei , Long Yi‐Tao 
Published: October 2018

AbstractThe rapid and precise measurement of dopamine (DA) levels is of great benefit to unveil physiological and pathological processes. The electrochemical detection approaches feature fast DA response, but remain challenging at the moment to realize ultra‐high sensitivity and selectivity to the trace amount of DA, especially in the presence of highly concentrated ascorbic acid (AA, the most common interferent in the human body). To address this issue, a negatively charged hybrid bilayer membrane (HBM) modified gold electrode was designed, which was only attractive to the positive DA but not the negative AA. As a result, this work managed to achieve an ultra‐low detection limit of 0.41 pM DA under the interference of AA of 109 times higher concentration. Such an excellent performance is over three orders of magnitude better than previously reported electrochemical sensing methods, suggesting the promise of applying HBM functionalization in electrochemical and bio‐sensing applications.
Countercation Effect on CO2 Binding to Oxo Titanate with Bulky Anilide Ligands
Authors: Paparo Albert , Silvia Jared S. , Spaniol Thomas P. , Okuda Jun , Cummins Christopher C. 
Published: October 2018

AbstractThis work focuses on nucleophilic activation of CO2 at the anionic terminal oxo titanium tris(anilide) complexes [(Solv)nM][OTi(N[tBu]Ar)3]m with M=Li, Na, K, Mg, MgMe, AlCl2, AlI2; Ar=3,5‐Me2C6H3; Solv=Et2O, THF, 12‐crown‐4, 2,2,2‐cryptand; n, m=1–2. The CO2 binding strength to the terminal oxo ligand of [OTi(N[tBu]Ar)3]− ([1]−) and the stability of the resulting carbonate moiety [O2COTi(N[tBu]Ar)3]− ([2]−) are highly dependent on the Lewis acidity of the countercation. We report herein on CO2 binding as a function of countercation and countercation coordination environment, and comment in this respect on the bottom and upper limits of the cation Lewis acidity. Thermodynamic parameters are provided for oxo complexes with lithium as countercation, that is, [(Et2O)2Li][1] and [(12‐c‐4)Li][1].
Size‐Selective Hydroformylation by a Rhodium Catalyst Confined in a Supramolecular Cage
Authors: Nurttila Sandra S. , Brenner Wolfgang , Mosquera Jesús , van Vliet Kaj M. , Nitschke Jonathan R. , Reek Joost N. H. 
Published: October 2018

AbstractSize‐selective hydroformylation of terminal alkenes was attained upon embedding a rhodium bisphosphine complex in a supramolecular metal–organic cage that was formed by subcomponent self‐assembly. The catalyst was bound in the cage by a ligand‐template approach, in which pyridyl–zinc(II) porphyrin interactions led to high association constants (>105 m−1) for the binding of the ligands and the corresponding rhodium complex. DFT calculations confirm that the second coordination sphere forces the encapsulated active species to adopt the ee coordination geometry (i.e., both phosphine ligands in equatorial positions), in line with in situ high‐pressure IR studies of the host–guest complex. The window aperture of the cage decreases slightly upon binding the catalyst. As a result, the diffusion of larger substrates into the cage is slower compared to that of smaller substrates. Consequently, the encapsulated rhodium catalyst displays substrate selectivity, converting smaller substrates faster to the corresponding aldehydes. This selectivity bears a resemblance to an effect observed in nature, where enzymes are able to discriminate between substrates based on shape and size by embedding the active site deep inside the hydrophobic pocket of a bulky protein structure.
Visible‐Light Direct Conversion of Ethanol to 1,1‐Diethoxyethane and Hydrogen over a Non‐Precious Metal Photocatalyst
Authors: Chao Yuguang , Zhang Wenqin , Wu Xuemei , Gong Nana , Bi Zhihong , Li Yunqin , Zheng Jianfeng , Zhu Zhenping , Tan Yisheng 
Published: October 2018

AbstractConverting renewable biomass and their derivatives into chemicals and fuels has received much attention to reduce the dependence on fossil resources. Photocatalytic ethanol dehydrogenation–acetalization to prepare value‐added 1,1‐diethoxyethane and H2 was achieved over non‐precious metal CdS/Ni‐MoS2 catalyst under visible light. The system displays an excellent production rate and high selectivity of 1,1‐diethoxyethane, 52.1 mmol g−1 h−1 and 99.2 %, respectively. In‐situ electron spin resonance, photoluminescence spectroscopy and transient photocurrent responses were conducted to investigate the mechanism. This study provides a promising strategy for a green application of bioethanol.
Synthesis of the Core Oligosaccharides of Lipooligosaccharides from Campylobacter jejuni: A Putative Cause of Guillain–Barré Syndrome
Authors: Yoshida Fumi , Yoshinaka Hiroki , Tanaka Hidenori , Hanashima Shinya , Yamaguchi Yoshiki , Ishihara Mikio , Saburomaru Miyuki , Kato Yuki , Saito Risa , Ando Hiromune , Kiso Makoto , Imamura Akihiro , Ishida Hideharu 
Published: October 2018

AbstractThe chemical synthesis of the highly branched core oligosaccharides of lipooligosaccharides (LOSs) found in Campylobacter jejuni, which causes Guillain–Barré syndrome by a preceding infection, is described. The target LOS mimics, consisting of eight or nine monosaccharides, were classified into three groups as key building blocks: ganglioside‐core tetra‐/pentasaccharides (GM1‐/GD1a‐like), l‐glycero‐d‐manno‐heptose‐containing trisaccharides, and 3‐deoxy‐d‐manno‐2‐octulosonic acid (KDO) residues. These synthetic fragments were obtained from commercially available monosaccharides. Less obtainable l‐glycero‐d‐manno‐heptose and KDO residues, as key components of the LOSs, were synthesized from p‐methoxyphenyl d‐mannoside and di‐O‐isopropylidene‐protected d‐mannose, respectively. The synthesis of α‐KDO glycoside, as one of the most difficult stereocontrolled glycosidic constructions, was achieved by treating a 2,3‐ene derivative of KDO with phenylselenyl trifluoromethanesulfonate as a suitable α‐directing reagent. All synthetic blocks were constructed through a convergent synthetic route, which resulted in the first synthesis of structurally challenging LOS core glycans containing ganglioside GM1 and GD1a‐core sequences.