bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrafast Synthesis of Ultrasmall Poly(Vinylpyrrolidone)‐Protected Bismuth Nanodots as a Multifunctional Theranostic Agent for In Vivo Dual‐Modal CT/Photothermal‐Imaging‐Guided Photothermal Therapy
Authors: Lei Pengpeng , An Ran , Zhang Peng , Yao Shuang , Song Shuyan , Dong Lile , Xu Xia , Du Kaimin , Feng Jing , Zhang Hongjie
Published: July 2017

To elaborately fabricate real‐time monitoring and therapeutic function into a biocompatible nanoplatform is a promising route in the cancer therapy field. However, the package of diagnosis and treatment into a single‐“element” nanoparticle remains challenge. Herein, ultrasmall poly(vinylpyrrolidone)‐protected bismuth nanodots (PVP‐Bi nanodots) are successfully synthesized through an ultrafacile strategy (1 min only under ambient conditions). The nanodots are easy to synthesize in both laboratory and large scale using low‐cost bismuth ingredients. PVP‐Bi nanodots with ultrasmall size show good biocompatibility. Due to the high X‐ray attenuation ability of Bi element, PVP‐Bi nanodots have prominent performance on X‐ray computed tomography (CT) imaging. Moreover, PVP‐Bi nanodots exhibit a high photothermal conversion efficiency (η = 30%) because of the strong near‐infrared absorbance, which can serve as nanotheranostic agent for photothermal imaging and cancer therapy. The subsequent PVP‐Bi‐nanodot‐mediated photothermal therapy (PTT) result shows highly efficient ablation of cancer cells both in vitro and in vivo. PVP‐Bi nanodots can be almost completely excreted from mice after 7 d. Blood biochemistry and histology analysis suggests that PVP‐Bi nanodots have negligible toxicity. All the positive results reveal that PVP‐Bi nanodots produced through the ultrafacile method are promising single‐“element” nanotheranostic platform for dual‐modal CT/photothermal‐imaging‐guided PTT.
Mechanically Tunable Bioink for 3D Bioprinting of Human Cells
Authors: Forget Aurelien , Blaeser Andreas , Miessmer Florian , Köpf Marius , Campos Daniela F. Duarte , Voelcker Nicolas H. , Blencowe Anton , Fischer Horst , Shastri V. Prasad
Published: July 2017

This study introduces a thermogelling bioink based on carboxylated agarose (CA) for bioprinting of mechanically defined microenvironments mimicking natural tissues. In CA system, by adjusting the degree of carboxylation, the elastic modulus of printed gels can be tuned over several orders of magnitudes (5–230 Pa) while ensuring almost no change to the shear viscosity (10–17 mPa) of the bioink solution; thus enabling the fabrication of 3D structures made of different mechanical domains under identical printing parameters and low nozzle shear stress. Human mesenchymal stem cells printed using CA as a bioink show significantly higher survival (95%) in comparison to when printed using native agarose (62%), a commonly used thermogelling hydrogel for 3D‐bioprinting applications. This work paves the way toward the printing of complex tissue‐like structures composed of a range of mechanically discrete microdomains that could potentially reproduce natural mechanical aspects of functional tissues.
Scaffold‐Free Liver‐On‐A‐Chip with Multiscale Organotypic Cultures
Authors: Weng Yu‐Shih , Chang Shau‐Feng , Shih Ming‐Cheng , Tseng Shih‐Heng , Lai Chih‐Huang
Published: July 2017

The considerable advances that have been made in the development of organotypic cultures have failed to overcome the challenges of expressing tissue‐specific functions and complexities, especially for organs that require multitasking and complex biological processes, such as the liver. Primary liver cells are ideal biological building blocks for functional organotypic reconstruction, but are limited by their rapid loss of physiological integrity in vitro. Here the concept of lattice growth used in material science is applied to develop a tissue incubator, which provides physiological cues and controls the 3D assembly of primary cells. The cues include a biological growing template, spatial coculture, biomimetic radial flow, and circulation in a scaffold‐free condition. The feasibility of recapitulating a multiscale physiological structural hierarchy, complex drug clearance, and zonal physiology from the cell to tissue level in long‐term cultured liver‐on‐a‐chip is demonstrated. These methods are promising for future applications in pharmacodynamics and personal medicine.
Extremely Low Density and Super‐Compressible Graphene Cellular Materials
Authors: Qiu Ling , Huang Bing , He Zijun , Wang Yuanyuan , Tian Zhiming , Liu Jefferson Zhe , Wang Kun , Song Jingchao , Gengenbach Thomas R. , Li Dan
Published: July 2017

Development of extremely low density graphene elastomer (GE) holds the potential to enable new properties that traditional cellular materials cannot offer, which are promising for a range of emerging applications, ranging from flexible electronics to multifunctional scaffolds. However, existing graphene foams with extremely low density are generally found to have very poor mechanical resilience. It is scientifically intriguing but remains unresolved whether and how the density limit of this class of cellular materials can be further pushed down while their mechanical resilience is being retained. In this work, a simple annealing strategy is developed to investigate the role of intersheet interactions in the formation of extreme‐low‐density of graphene‐based cellular materials. It is discovered that the density limit of mechanically resilient cellular GEs can be further pushed down as low as 0.16 mg cm−3 through thermal annealing. The resultant extremely low density GEs reveal a range of unprecedented properties, including complete recovery from 98% compression in both of liquid and air, ultrahigh solvent adsorption capacity, ultrahigh pressure sensitivity, and light transmittance.
Ferroelectrics as Smart Mechanical Materials
Authors: Cordero‐Edwards Kumara , Domingo Neus , Abdollahi Amir , Sort Jordi , Catalan Gustau
Published: July 2017

The mechanical properties of materials are insensitive to space inversion, even when they are crystallographically asymmetric. In practice, this means that turning a piezoelectric crystal upside down or switching the polarization of a ferroelectric should not change its mechanical response. Strain gradients, however, introduce an additional source of asymmetry that has mechanical consequences. Using nanoindentation and contact‐resonance force microscopy, this study demonstrates that the mechanical response to indentation of a uniaxial ferroelectric (LiNbO3) does change when its polarity is switched, and use this mechanical asymmetry both to quantify its flexoelectricity and to mechanically read the sign of its ferroelectric domains.
Polarized Light‐Emitting Diodes Based on Patterned MoS2 Nanosheet Hole Transport Layer
Authors: Choi Gyu Jin , Van Le Quyet , Choi Kyoung Soon , Kwon Ki Chang , Jang Ho Won , Gwag Jin Seog , Kim Soo Young
Published: July 2017

Here, this study successfully fabricates few‐layer MoS2 nanosheets from (NH4)2MoS4 and applies them as the hole transport layer as well as the template for highly polarized organic light‐emitting diodes (OLEDs). The obtained material consists of polycrystalline MoS2 nanosheets with thicknesses of 2 nm. The MoS2 nanosheets are patterned by rubbing/ion‐beam treatment. The Raman spectra shows that {poly(9,9‐dioctylfluorene‐alt‐benzothiadiazole), poly[(9,9‐di‐n‐octylfluorenyl‐2,7‐diyl)‐alt‐(benzo[2,1,3]thiadiazol‐4,8‐diyl)]} (F8BT) on patterned MoS2 exhibits distinctive polarization behavior. It is discovered that patterned MoS2 not only improves the device efficiency but also changes the polarization behavior of the devices owing to the alignment of F8BT. This work demonstrates a highly efficient polarized OLED with a polarization ratio of 62.5:1 in the emission spectrum (166.7:1 at the peak intensity of 540 nm), which meets the manufacturing requirement. In addition, the use of patterned MoS2 nanosheets not only tunes the polarization of the OLEDs but also dramatically improves the device performance as compared with that of devices using untreated MoS2.
Two‐Photon Absorption‐Free Ultrafast Optical Switching in Carbon‐Rich SixC1−x Microring
Authors: Huang Bo‐Ji , Wu Chung‐Lun , Lin Yung‐Hsiang , Wang Huai‐Yung , Tsai Cheng‐Ting , Cheng Chih‐Hsien , Chi Yu‐Chieh , Chang Po‐Han , Wu Chih‐I , Soref Richard A. , Lin Gong‐Ru
Published: July 2017

Ultrafast Kerr effect switching in near‐infrared two‐photon absorption (TPA)‐free and free‐carrier‐absorption (FCA)‐free nonstoichiometric silicon carbide (SixC1−x) microring waveguides is performed and investigated. With pulsed return‐to‐zero on–off‐keying (PRZ‐OOK) stream for the Si‐rich SixC1−x‐based all‐optical switches, the inversely modulated probe reveals an asymmetric bit shape data extinction ratio (ER) of only 8.7 dB owing to the TPA + FCA effect. By eliminating the FCA effects in nearly stoichiometric SixC1−x microring waveguide, the high‐speed wavelength conversion of a data stream with an ER of 14 dB can be observed when coinciding the probe wavelength with the transmission dip. Slightly deviating the probe wavelength from the transmission dip, most probe power still remains in bus waveguide to cause a strong FCA effect to degrade the ER down to 7.4 dB. A symmetrically converted and inverted data stream with high on/off extinction can be observed in the C‐rich SixC1−x‐based microring waveguide with completely suppressed trailing‐edge response. To further approach the upper limitation on bandwidth, the wavelength‐converted and sign‐reversible PRZ‐OOK data switching at a bit rate up to 12 Gbit s−1 can be obtained with similar ER of better than 20 dB, as contributed mainly by the enhanced Kerr nonlinearity in the C‐rich SixC1−x.
Biocompatible and Flexible Hydrogel Diode‐Based Mechanical Energy Harvesting
Authors: Zhou Yue , Hou Ying , Li Qi , Yang Lu , Cao Ye , Choi Kyoung Hwan , Wang Qing , Zhang Q. M.
Published: July 2017

Energy harvesting devices which convert low frequency mechanical energy sources such as human motions and ocean waves into electricity are attractive for powering portable devices and for green‐energy generation. To date the state‐of‐the‐art mechanical energy harvesting devices can only work efficiently at high vibration frequencies. Here, a biocompatible and flexible mechanical energy harvesting device is reported utilizing ionic diode as the transducer. This device utilizes the redistribution of cations and anions at the two hydrogel electrodes under stress to convert mechanical energy to electricity. It is shown that the device can be operated at low frequencies with high output current, e.g., 13.5 µA cm−2, owing to the high ion concentration and unique working mechanism of the device. Moreover, the output current density and power density can be improved further by employing a multilayer configuration. By stacking five units with parallel structure, the hydrogel diode device can generate an output current of 64.3 µA cm−2 and power density of 0.48 µW cm−2. Considering the very high electric energy density of ionic devices, the hydrogel energy harvesting device demonstrated herein paves a way for efficient mechanical energy harvesting from many common low frequency sources.
Exciton Transport in Molecular Aggregates – From Natural Antennas to Synthetic Chromophore Systems
Authors: Brixner Tobias , Hildner Richard , Köhler Jürgen , Lambert Christoph , Würthner Frank
Published: July 2017

The transport of excitation energy in molecular aggregates is of crucial importance for the function of organic optoelectronic devices and next‐generation solar cells. First, this review summarizes the theoretical background of the nature of the electronically excited states of molecular aggregates. For these systems, the electronic interaction between the monomers leads to the formation of exciton states. This goes along with a shift of the excitation energies and a redistribution of the oscillator strength with respect to the monomers. Next, a brief overview is provided over experimental techniques that allow to study the properties of excitons in molecular aggregates. This includes single‐molecule spectroscopy, coherent two‐dimensional (2D) spectroscopy, and single‐molecule coherent spectroscopy. Finally, examples of molecular aggregates spanning the range from natural systems that act in photosynthesis as light‐harvesting antennas to artificial aggregates built from synthetic chromophores are illustrated.
A Postspinel Anode Enabling Sodium‐Ion Ultralong Cycling and Superfast Transport via 1D Channels
Authors: Li Qi , Guo Shaohua , Zhu Kai , Jiang Kezhu , Zhang Xiaoyu , He Ping , Zhou Haoshen
Published: July 2017

Sodium‐ion batteries are intensively investigated for large‐scale energy storage due to the favorable sodium availability. However, the anode materials have encountered numerous problems, such as insufficient cycling performance, dissatisfactory capacity, and low safety. Here, a novel post‐spinel anode material, i.e., single‐crystalline NaVSnO4, is presented with the confined 1D channels and the shortest diffusion path. This material delivers an ultra long cycling life (84% capacity retention after 10 000 cycles), a high discharging capacity (163 mA h g−1), and a safe average potential of 0.84 V. Results indicate that the post‐spinel structure is well maintained over 10 000 cycles, surprisingly, with 0.9% volume change, the Sn4+/Sn2+ based redox enables two sodium ions for reversible release and uptake, and the diffusion coefficient of sodium ions is characterized by 1.26 × 10−11 cm2 s−1. The findings of this study provide a new insight into design of new frameworks with polyelectronic transfers for full performance electrode materials of sodium‐ion batteries.
Polymer Main‐Chain Substitution Effects on the Efficiency of Nonfullerene BHJ Solar Cells
Authors: Firdaus Yuliar , Maffei Luna Pratali , Cruciani Federico , Müller Michael A. , Liu Shengjian , Lopatin Sergei , Wehbe Nimer , Ndjawa Guy O. Ngongang , Amassian Aram , Laquai Frederic , Beaujuge Pierre M.
Published: July 2017

“Nonfullerene” acceptors are proving effective in bulk heterojunction (BHJ) solar cells when paired with selected polymer donors. However, the principles that guide the selection of adequate polymer donors for high‐efficiency BHJ solar cells with nonfullerene acceptors remain a matter of some debate and, while polymer main‐chain substitutions may have a direct influence on the donor–acceptor interplay, those effects should be examined and correlated with BHJ device performance patterns. This report examines a set of wide‐bandgap polymer donor analogues composed of benzo[1,2‐b:4,5‐b′]dithiophene (BDT), and thienyl ([2H]T) or 3,4‐difluorothiophene ([2F]T) motifs, and their BHJ device performance pattern with the nonfullerene acceptor “ITIC”. Studies show that the fluorine‐ and ring‐substituted derivative PBDT(T)[2F]T largely outperforms its other two polymer donor counterparts, reaching power conversion efficiencies as high as 9.8%. Combining several characterization techniques, the gradual device performance improvements observed on swapping PBDT[2H]T for PBDT[2F]T, and then for PBDT(T)[2F]T, are found to result from (i) notably improved charge generation and collection efficiencies (estimated as ≈60%, 80%, and 90%, respectively), and (ii) reduced geminate recombination (being suppressed from ≈30%, 25% to 10%) and bimolecular recombination (inferred from recombination rate constant comparisons). These examinations will have broader implications for further studies on the optimization of BHJ solar cell efficiencies with polymer donors and a wider range of nonfullerene acceptors.
Quantum Zeno Dynamics Through Stochastic Protocols
Authors: Müller Matthias M. , Gherardini Stefano , Caruso Filippo
Published: July 2017

Quantum measurements play a crucial role in quantum mechanics since they perturb, unavoidably and irreversibly, the state of the measured quantum system. More extremely, the constant observation of a quantum system can even freeze its dynamics to a subspace, effectively truncating the Hilbert space of the system. It represents the quantum version of the famous flying arrow Zeno paradox, and is called quantum Zeno dynamics. In general, it can be obtained by applying frequent consecutive quantum measurements that are equally spaced in time. Here, we introduce time disorder in the measurement sequence, and analytically investigate how this temporal stochasticity may affect the confinement probability of the system in the subspace. As main result, we then exploit how different dissipative and coherent Zeno protocols can be generalized to this stochastic scenario. Finally, our analytical predictions are numerically tested on a paradigmatic spin chain where we find a trade‐off between a probabilistic scheme with high fidelity (compared to perfect subspace dynamics) and a deterministic one with a slightly lower fidelity, moving further steps towards new schemes of Zeno‐based control for future quantum technologies.
Graphene Nanoribbons for Electronic Devices
Authors: Geng Zhansong , Hähnlein Bernd , Granzner Ralf , Auge Manuel , Lebedev Alexander A. , Davydov Valery Y. , Kittler Mario , Pezoldt Jörg , Schwierz Frank
Published: July 2017

Graphene nanoribbons show unique properties and have attracted a lot of attention in the recent past. Intensive theoretical and experimental studies on such nanostructures at both the fundamental and application‐oriented levels have been performed. The present paper discusses the suitability of graphene nanoribbons devices for nanoelectronics and focuses on three specific device types – graphene nanoribbon MOSFETs, side‐gate transistors, and three terminal junctions. It is shown that, on the one hand, experimental devices of each type of the three nanoribbon‐based structures have been reported, that promising performance of these devices has been demonstrated and/or predicted, and that in part they possess functionalities not attainable with conventional semiconductor devices. On the other hand, it is emphasized that – in spite of the remarkable progress achieved during the past 10 years – graphene nanoribbon devices still face a lot of problems and that their prospects for future applications remain unclear.
Modulated Structure Calculated for Superconducting Hydrogen Sulfide
Authors: Majumdar Arnab , Tse John S. , Yao Yansun
Published: July 2017

Compression of hydrogen sulfide using first principles metadynamics and molecular dynamics calculations revealed a modulated structure with high proton mobility which exhibits a diffraction pattern matching well with experiment. The structure consists of a sublattice of rectangular meandering SH− chains and molecular‐like H3S+ stacked alternately in tetragonal and cubic slabs forming a long‐period modulation. The novel structure offers a new perspective on the possible origin of the superconductivity at very high temperatures in which the conducting electrons in the SH chains are perturbed by the fluxional motions of the H3S resulting in strong electron‐phonon coupling.
Discovery and Total Synthesis of Natural Cystobactamid Derivatives with Superior Activity against Gram‐Negative Pathogens
Authors: Hüttel Stephan , Testolin Giambattista , Herrmann Jennifer , Planke Therese , Gille Franziska , Moreno Maria , Stadler Marc , Brönstrup Mark , Kirschning Andreas , Müller Rolf
Published: July 2017

Antibiotic discovery and development is challenging as chemical scaffolds of synthetic origin often lack the required pharmaceutical properties, and the discovery of novel ones from natural sources is tedious. Herein, we report the discovery of new cystobactamids with a significantly improved antibacterial profile in a detailed screening of myxobacterial producer strains. Some of these new derivatives display antibacterial activities in the low‐μg mL−1 range against Gram‐negative pathogens, including clinical isolates of Klebsiella oxytoca, Pseudomonas aeruginosa, and fluoroquinolone‐resistant Enterobacteriaceae, which were not observed for previously reported cystobactamids. Our findings provide structure–activity relationships and show how pathogen resistance can be overcome by natural scaffold diversity. The most promising derivative 861‐2 was prepared by total synthesis, enabling further chemical optimization of this privileged scaffold.
Copper(I) complex covalently anchored on graphene oxide as an efficient and recyclable catalyst for Sonogashira reaction
Authors: Fath Roghayeh Hashemi , Hoseini S. Jafar
Published: July 2017

In this study, the organosilane‐functionalized graphene oxide as a stabilizer was prepared by a facile one‐step silylation approach. [Cu(PPh3)3Cl] complex was successfully immobilized onto the graphene oxide surface through coordination interaction with organosilane ligand spacers. The supported catalyst showed enhanced catalytic performance toward Sonogashira reaction of aryl halides with phenylacetylene in water solvent compared with the homogeneous analogues, and it could be readily recycled and reused several times without discernible loss of its activity.
Tribological behaviors of polyurethane composites containing self‐lubricating microcapsules and reinforced by short carbon fibers
Authors: Mu Bo , Li Xin , Yang Baoping , Cui Jinfeng , Wang Xia , Guo Junhong , Bao Xuemei , Chen Li
Published: July 2017

Self‐lubricating microcapsules containing methyl silicone oil as core materials, were prepared with poly(melamine‐formaldehyde) as shell material by in situ polymerization method. Combining with synergistic effect of the short carbon fibers (SCFs) which were systematically treated by liquid‐phase oxidation and chemical grafting, they were simultaneously adopted as reinforcing additives to improve the tribological and mechanical properties of polyurethane materials. The tribological behaviors and mechanical properties of the polyurethane composites have been investigated by a block‐on‐ring wear tester and electronic universal testing machine, respectively. The results indicate that the friction coefficient and wear rate of polyurethane composites without SCFs significantly decreased with increased self‐lubricating microcapsule concentration from 2.5 to 10 wt % due to the release of methyl silicone oil; meanwhile, the polyurethane composites filled with 10 wt % microcapsule and 15 wt % SCFs not only exhibited the lowest friction and wear behaviors, but also improved mechanical strength and thermal stability of polyurethane composites. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45331.
Porosity reduction of polyethylene glycol phase change materials by using nanoscale thermal‐energy‐conducting medium during crystallization process
Authors: Zhang Haiquan , Sun Qinrong , Yuan Yanping , Cao Xiaoling
Published: July 2017

Poly(ethylene glycols) (PEGs) are phase change materials (PCMs) that exhibit undesirable heat transfer properties, which restrict their industrial utility. Apart from the intrinsic material properties, a large quantity of micropores in the crystalline PEG polymers cause poor heat transfer performance. In this work, the formation and growth of micropores are reported through in situ characterization. The addition of a nanoscale thermal‐energy‐conducting medium into PCMs has been proposed for reducing their porosity. The mechanism for reducing porosity is reported for prepared composite PCMs. The intrinsic causes are thought to be the following. Metal oxide nanoparticles can migrate with the liquid PEG flow, which can reduce the thermal stresses in the crystal growth process. In addition, the nanoscale medium promotes heterogeneous nucleation. The results of this study show that reducing the porosity of the polymer crystals is an important approach for improving the heat transfer properties of the PEG PCMs. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45446.
Isothermal crystallization kinetics and spherulite morphologies of poly(lactic acid)/ethylene acrylate copolymer blends
Authors: Mat Taib Razaina , Tham Cho Yin
Published: July 2017

Isothermal crystallization kinetics and spherulite morphologies of partially immiscible blends of poly(lactic acid) (PLA) and ethylene acrylate copolymer (EAC) were investigated by differential scanning calorimetry (DSC) and polarized optical microscopy. The DSC data obtained was analyzed using the Avrami equation. Crystallization kinetics of PLA from the melt was strongly influenced by the blend composition and the crystallization temperature. At a given crystallization temperature, the overall crystallization rate value was greater in the blends than in PLA suggesting that the presence of EAC enhanced crystallization of PLA. Polarized optical micrographs showed that the crystallization of PLA initially took place at the PLA/EAC interface. At high EAC content (>1 wt %), EAC domains acted as hindrance to crystallization reducing the overall crystallization rate of PLA in the blends. Based on the DSC analysis, the crystallization rate was maximum when PLA blend with 1 wt % EAC was isothermally crystallized at 103 °C. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45487.
Synergistic effects of dual imidazolium polyoxometalates on intumescent flame retardant polypropylene
Authors: Wang Chengle , Wang Zhijing , Li Juan
Published: July 2017

The role of dual imidazolium polyoxometalates (POMs) in the flame retardancy of polypropylene/intumescent flame retardant (PP/IFR) composites was studied. The results showed that the structures of dual imidazolium POMs have a great effect on the flame retardancy of PP composites. The dual imidazolium POMs based on an ethyl group (EMIPMA) obtain the best flame retardant efficiency. With 15.5 wt % IFR and 0.5 wt % EMIPMA, the PP composites reach a limiting oxygen index of 25.7 and the UL‐94 V‐0 standard. However, the dual imidazolium POMs containing a butyl (BMIPMA) or hexyl (HMIPMA) group cannot achieve the UL‐94 V‐0 standard at the same formulation. Dual imidazolium POMs not only promote the formation of good char, but also induce the formation of intumescent char with a hierarchical and microporous structure that helps to prevent gas and heat from transferring from the flame to the resin. Therefore, the flame retardancy of PP/IFR composites is improved. However, excessive combustible components produced by BMIPMA or HMIPMA deteriorate the flame retardancy of PP/IFR composites. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45491.
Preparation of poly(acrylamide‐co‐acrylic acid)/silica nanocomposite microspheres and their performance as a plugging material for deep profile control
Authors: Ji Jingqi , Zeng Chenlu , Ke Yangchuan , Pei Yang
Published: July 2017

In this work, poly(acrylamide‐co‐acrylic acid)/silica [poly(AM‐co‐AA)/SiO2] microspheres were prepared by inverse phase suspension polymerization in the presence of γ‐3‐(trimethoxysilyl) propyl methacrylate (or 3‐methacryloxypropyltrimethoxysilane) modified SiO2. The effects of SiO2 nanoparticles on tuning morphology and properties of the nanocomposite microspheres were studied. Plugging ability and oil displacement performance were also systematically investigated by single‐ and double‐tube sand pack models. The results showed that SiO2 nanoparticles can effectively adjust surface smoothness, swelling behavior, and thermal stability of the nanocomposite microspheres. Compared with pure copolymer microspheres, these nanocomposite microspheres also displayed better salt tolerance and shear resistance. Such multifunctional nanocomposite microspheres can provide effective plugging in the high‐permeability channels and can also achieve deep profile control. The highest plugging rate can be 86.11% and the oil recovery for low‐permeability tube was enhanced by 19.69%. This research will provide a candidate material for the further enhanced oil recovery (EOR) research and supply the theoretical support for profile control system in field application. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45502.
Mesoporous water adsorbent material from poly high internal phase emulsion for agriculture application
Authors: Preechawong Jitima , Chindacharin Supakorn , Sapsrithong Pornsri , Nithitanakul Manit
Published: July 2017

Mesoporous water adsorbent materials were prepared by high internal phase emulsion (HIPE) technique: a technique which used aqueous phase (water phase) as a temporary template (in the form of droplets) and oil phase (polymer phase) as a continuous structure. This research describes the preparation of porous poly[S/ethylene glycol dimethylacrylate (EGDMA)]HIPE from styrene crosslinked with EGDMA. Effects of chemical composition on the pores of the mesoporous adsorbents were investigated. The EGDMA concentration was varied between 0 and 40% of oil phase by total volume to give polyHIPE with various amounts of hydroxyl groups. Effects of oil: aqueous phase ratio on mesoporous adsorbent polyHIPEs resulted in interconnected pores in their morphology. The EGDMA concentration also affected the obtained polyHIPE morphology. The water adsorption of poly(S/EGDMA)HIPE gave high water adsorption, up to 350% of dry weight. The obtained polyHIPE with large average pore size were also found to give high water adsorption capacity. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45509.
Synovial Immunophenotype and Anti–Citrullinated Peptide Antibodies in Rheumatoid Arthritis Patients
Authors: Orr Carl , Najm Aurelie , Biniecka Monika , McGarry Trudy , Ng Chin‐Teck , Young Francis , Fearon Ursula , Veale Douglas J.
Published: July 2017

Objective

Serum anti–citrullinated peptide antibodies (ACPAs) may be present before the development of rheumatoid arthritis (RA) and may be predictive of more severe, erosive disease. This study was undertaken to examine the synovial tissue immunophenotype according to ACPA status in patients with RA, as well as the response to treatment and erosion status.

Methods

Consecutive RA patients were prospectively recruited and underwent clinical and serologic assessments before and after treatment. Radiologic assessment was performed at the time of clinical follow‐up. Synovial tissue was immunostained for specific markers of B cells (CD19), T cells (CD3, CD4, and CD8), macrophages (CD68), and blood vessels (factor VIII). Serum CXCL13 levels were quantified by enzyme‐linked immunosorbent assay. Synovial tissue sections were analyzed for immunophenotype according to ACPA status, using a validated semiquantitative scoring method, and also analyzed for the presence of lymphoid aggregates. Response to treatment with nonbiologic or biologic disease‐modifying antirheumatic drugs was assessed using the European League Against Rheumatism (EULAR) response criteria.

Results

In total, 123 subjects (78 ACPA+) were included. Compared to ACPA– RA patients, synovium from ACPA+ RA patients was characterized by significantly higher levels of CD19+ B cells and CD3+ and CD8+ T cells (each P < 0.05), and CD19+ B cell levels were significantly higher in patients who were naive to treatment. The CD19+ B cell infiltrate level was higher in patients with erosions at follow‐up (P = 0.0128). Levels of lymphoid aggregates of CD19+ B cells were significantly higher in ACPA+ patients (P < 0.05), and this was associated with increased serum CXCL13 levels. The EULAR response was significantly associated with the level of CD3+ T cell infiltrates (P < 0.05), while CD68+ macrophage and CD8+ T cell levels were predictive of the response to tumor necrosis factor inhibitors (P < 0.05).

Conclusion

The results of this prospective study demonstrate that the levels of synovial B cell infiltrates and lymphoid aggregates were significantly higher in ACPA+ RA patients, especially those who were naive to treatment. In addition, ACPA+ subjects developed more erosions during progression of the disease and had higher serum levels of CXCL13. The EULAR response to therapy in ACPA+ RA patients was associated with increased levels of T cell and macrophage markers.
Synthesis, Structure, and Properties of Near‐Infrared [b]Phenanthrene‐Fused BF2 Azadipyrromethenes
Authors: Cui Jiuen , Sheng Wanle , Wu Qinghua , Yu Changjiang , Hao Erhong , Bobadova‐Parvanova Petia , Storer Marie , Asiri Abdullah M. , Marwani Hadi M. , Jiao Lijuan
Published: July 2017

A new class of phenanthrene‐fused BF2 azadipyrromethene (azaBODIPY) dyes have been synthesized through a tandem Suzuki reaction and oxidative ring‐fusion reaction, or a palladium‐catalyzed intramolecular C−H activation reaction. These phenanthrene‐fused azaBODIPY dyes are highly photostable and display markedly redshifted absorption (up to λ=771 nm) and emission bands (λ≈800 nm) in the near‐infrared region. DFT calculations and cyclic voltammetry studies indicate that, upon annulation, more pronounced stabilization of the LUMO is the origin of the bathochromic shift of the absorption and high photostability.
Innovative Bohrverfahren und ihr Einfluss auf die Beschaffenheit und Geometrie von Bohrlöchern
Authors: Schwenn Michael , Lamplmair Stefan , Zeman Oliver , Bergmeister Konrad
Published: July 2017

Nachträglich installierte Befestigungen sind aus der Baupraxis nicht mehr wegzudenken und seit Jahrzehnten erfolgreich im Einsatz. Technologische Innovationen und vermehrt geänderte Rahmenbedingungen beim Einbau nachträglicher Befestigungen führen zu einem ansteigenden Einsatz alternativer Bohrmethoden. Im Gegensatz zum klassischen Hammerbohrer (Mauerbohrer) zählen hierzu u. a. Bohrer mit integrierter Bohrlochreinigung (Saugbohrer bzw. Hohlbohrer) und Diamantbohrsysteme, welche in Ausführungen mit und ohne Wasserkühlung eingesetzt werden. An Hammerbohrer werden im Bereich der nachträglichen Befestigungen durch die entsprechende Bewertung bzw. Zulassung bestimmte Anforderungen gestellt, was die einzuhaltenden Toleranzen des Schneidendurchmessers betrifft. In diesem Beitrag wird die Fragestellung behandelt, inwiefern die Geometrie und Oberflächenbeschaffenheit von Bohrlöchern, welche mit alternativen Bohrmethoden hergestellt wurden, durch den Einsatz ebendieser beeinflusst wird. In einem ersten Schritt werden auf Grundlage einer Oberflächenanalyse die verschiedenen Bohrmethoden klassifiziert. Darauf aufbauend erfolgt auf der Grundlage eines dreidimensionalen Modells des Bohrlochs ein direkter Vergleich zwischen hammer‐ und diamantgebohrten Bohrlöchern. Dabei zeigt sich, dass das gemessene Bohreckmaß bei einem Diamantbohrer eine andere Geometrie im Bohrloch verursacht, als dies bei Hammerbohrern der Fall ist. Diese geometrischen Verhältnisse können sich auf die Tragfähigkeit von Befestigungen auswirken.
Transcriptional regulation of APP by apoE: To boldly go where no isoform has gone before
Authors: Lee Liying Corinne , Goh Michele Q. L. , Koo Edward H.
Published: July 2017

Alzheimer's disease (AD) is the most common form of dementia that gradually disrupts the brain network to impair memory, language and cognition. While the amyloid hypothesis remains the leading proposed mechanism to explain AD pathophysiology, anti‐amyloid therapeutic strategies have yet to translate into useful therapies, suggesting that amyloid β‐protein and its precursor, the amyloid precursor protein (APP) are but a part of the disease cascade. Further, risk of AD can be modulated by a number of factors, the most impactful being the ɛ4 isoform of apolipoprotein E (apoE). A recent study reported a novel isoform‐dependent transcriptional regulation of APP by apoE. These interesting new results add to the myriad of mechanisms that have been proposed to explain how apoE4 enhances AD risk, highlighting the complexities of not only apoE and AD pathophysiology, but also of disease itself. Also see the video abstract here: https://youtu.be/yd14MBdPkCY
Polyol Structure Influences Enzymatic Hydrolysis of Bio‐Based 2,5‐Furandicarboxylic Acid (FDCA) Polyesters
Authors: Haernvall Karolina , Zitzenbacher Sabine , Amer Hassan , Zumstein Michael T. , Sander Michael , McNeill Kristopher , Yamamoto Motonori , Schick Michael B. , Ribitsch Doris , Guebitz Georg M.
Published: July 2017

Polyesters of 2,5‐furandicarboxylic acid (FDCA) have gained attention as they can be regarded as the bio‐based alternatives to the petroleum‐based polyesters of terephthalic acid. However, only little is known about the biodegradation and enzymatic hydrolysis of FDCA‐based polyesters. This work aims to investigate the influence of different polyols on enzymatic hydrolysis of FDCA‐based polyesters. A series of polyesters containing various polyols are synthesized and analyzed regarding susceptibility to enzymatic hydrolysis by cutinase 1 from Thermobifida cellulosilytica (Thc_Cut1). FDCA‐based polyesters’ number average molecular weight (Mn) ranged from 9360–35 800 g mol−1 according to gel permeation chromatography (GPC) analysis. Differential scanning calorimetry (DSC) analyses show decreasing glass transition temperature (Tg) with increasing diol chain length. Crystallinity of all polyesters is below 1% except for polyesters containing 1,6‐hexanediol, 1,8‐octanediol, and 1,12‐dodecanediol for which calculated crystallinities are 27, 37, and 30%, respectively. Thc_Cut1 hydrolyzes all tested polyesters with preference for polyesters containing 1,5‐pentanediol and 1,9‐nonanediol (57.7 ± 7.5 and 52.8 ± 4.0% released FDCA). Enzyme activity increases when the linear diol 1,3‐propanediol is replaced by the branched analog 1,2‐propanediol or ethoxy units are introduced into the polyester chain. The results will contribute to expand the knowledge of microbial biodegradation of FDCA‐based polyesters.
Improvement of d‐Lactic Acid Production in Saccharomyces cerevisiae Under Acidic Conditions by Evolutionary and Rational Metabolic Engineering
Authors: Baek Seung‐Ho , Kwon Eunice Y. , Bae Sang‐Jeong , Cho Bo‐Ram , Kim Seon‐Young , Hahn Ji‐Sook
Published: July 2017

Microbial lactic acid (LA) production under acidic fermentation conditions is favorable to reduce the production cost, but circumventing LA toxicity is a major challenge. A d‐LA‐producing Saccharomyces cerevisiae strain JHY5610 is generated by expressing d‐lactate dehydrogenase gene (Lm. ldhA) from Leuconostoc mesenteroides, while deleting genes involved in ethanol production (ADH1, ADH2, ADH3, ADH4, and ADH5), glycerol production (GPD1 and GPD2), and degradation of d‐LA (DLD1). Adaptive laboratory evolution of JHY5610 lead to a strain JHY5710 having higher LA tolerance and d‐LA‐production capability. Genome sequencing of JHY5710 reveal that SUR1I245S mutation increases LA tolerance and d‐LA‐production, whereas a loss‐of‐function mutation of ERF2 only contributes to increasing d‐LA production. Introduction of both SUR1I245S and erf2Δ mutations into JHY5610 largely mimic the d‐LA‐production capability of JHY5710, suggesting that these two mutations, which could modulate sphingolipid production and protein palmitoylation, are mainly responsible for the improved d‐LA production in JHY5710. JHY5710 is further improved by deleting PDC1 encoding pyruvate decarboxylase and additional integration of Lm. ldhA gene. The resulting strain JHY5730 produce up to 82.6 g L−1 of d‐LA with a yield of 0.83 g g−1 glucose and a productivity of 1.50 g/(L · h) in fed‐batch fermentation at pH 3.5.
Rewiring the Glucose Transportation and Central Metabolic Pathways for Overproduction of N‐Acetylglucosamine in Bacillus subtilis
Authors: Gu Yang , Deng Jieying , Liu Yanfeng , Li Jianghua , Shin Hyun‐dong , Du Guocheng , Chen Jian , Liu Long
Published: July 2017

N‐acetylglucosamine (GlcNAc) is an important amino sugar extensively used in the healthcare field. In a previous study, the recombinant Bacillus subtilis strain BSGN6‐PxylA‐glmS‐pP43NMK‐GNA1 (BN0‐GNA1) had been constructed for microbial production of GlcNAc by pathway design and modular optimization. Here, the production of GlcNAc is further improved by rewiring both the glucose transportation and central metabolic pathways. First, the phosphotransferase system (PTS) is blocked by deletion of three genes, yyzE (encoding the PTS system transporter subunit IIA YyzE), ypqE (encoding the PTS system transporter subunit IIA YpqE), and ptsG (encoding the PTS system glucose‐specific EIICBA component), resulting in 47.6% increase in the GlcNAc titer (from 6.5 ± 0.25 to 9.6 ± 0.16 g L−1) in shake flasks. Then, reinforcement of the expression of the glcP and glcK genes and optimization of glucose facilitator proteins are performed to promote glucose import and phosphorylation. Next, the competitive pathways for GlcNAc synthesis, namely glycolysis, peptidoglycan synthesis pathway, pentose phosphate pathway, and tricarboxylic acid cycle, are repressed by initiation codon‐optimization strategies, and the GlcNAc titer in shake flasks is improved from 10.8 ± 0.25 to 13.2 ± 0.31 g L−1. Finally, the GlcNAc titer is further increased to 42.1 ± 1.1 g L−1 in a 3‐L fed‐batch bioreactor, which is 1.72‐fold that of the original strain, BN0‐GNA1. This study shows considerably enhanced GlcNAc production, and the metabolic engineering strategy described here will be useful for engineering other prokaryotic microorganisms for the production of GlcNAc and related molecules.
A Strong Hybrid Fatty Acid Inducible Transcriptional Sensor Built From Yarrowia lipolytica Upstream Activating and Regulatory Sequences
Authors: Shabbir Hussain Murtaza , Wheeldon Ian , Blenner Mark A.
Published: July 2017

The engineering of Yarrowia lipolytica to accumulate lipids with high titers and productivities has been enabled with a handful of constitutive promoters for pathway engineering. However, the development of promoters that are both strong and lipid responsive could greatly benefit the bioproduction efficiency of lipid‐derived oleochemicals in oleaginous yeast. In this study, a fatty acid regulated hybrid promoter for use in Y. lipolytica is engineered. A 200 bp upstream regulatory sequence in the peroxisomal acyl CoA oxidase 2 (POX2) promoter is identified. Further analysis of the promoter sequence reveal a regulatory sequence, that when used in tandem repeats, lead to a 48‐fold induction of gene expression relative to glucose and fourfold higher than the native POX2 promoter. To date, this is the strongest inducible promoter reported in Y. lipolytica. Taken together, the results show that it is possible to engineer strong promoters that retain strong inducibility. These types of promoters will be useful in controlling metabolism and as fatty acid sensors.
Improved PKS Gene Expression With Strong Endogenous Promoter Resulted in Geldanamycin Yield Increase
Authors: Wang Xinran , Ning Xinjuan , Zhao Qinqin , Kang Qianjin , Bai Linquan
Published: July 2017

The type I polyketide geldanamycin is a potent anti‐tumor reagent. Its biosynthesis includes three steps: the biosynthesis of precursors, such as 3‐amino‐5‐hydroxybenzoic acid (AHBA), the polyketide synthase (PKS) chain extension, and the post‐PKS modifications. According to the genomic and transcriptomic analysis, the PKS chain extension was deduced to be the rate‐limiting step for geldanamycin production in Streptomyces hygroscopicus XM201. In order to improve the expression of PKS genes, a strong endogenous promoter 5063p was obtained based on the transcriptomic analysis and XylE enzymatic assay. By replacing the native PKS promoter gdmA1p with 5063p, the expression of the PKS genes during geldanamycin fermentation was increased by 4–141‐folds, and the geldanamycin yield was increased by 39%. Interestingly, AHBA feeding experiment showed that the supply of AHBA in turn become a new rate‐limiting factor for geldanamycin production. Further combined overexpression of the 6‐gene AHBA biosynthetic cassette and PKS genes increased the yield of geldanamycin by 88%, from 773 mg L−1 of the wild‐type to 1450 mg L−1 in the derived strain. Our results suggested that improved expression of all PKS genes in a particular biosynthetic gene cluster is important for the yield increase of the corresponding polyketide natural product.
Residual dynamic and risk assessment of dimethomorph in Swiss chard grown at two different sites
Authors: Kabir Md. Humayun , Abd El‐Aty A. M. , Rahman Md. Musfiqur , Chung Hyung Suk , Lee Han Sol , Kim Mi‐Ra , Chang Byung‐Joon , Wang Jing , Shin Ho‐Chul , Shim Jae‐Han
Published: July 2017

Residue analysis of dimethomorph in Swiss chard cultivated at two different locations under greenhouse conditions was conducted using high‐performance liquid chromatography–ultraviolet detection and confirmed by tandem mass spectrometry. The randomly collected samples (over 14 days) were extracted with acetonitrile and purified using a Florisil solid‐phase extraction cartridge. Linearity over a concentration range of 0.05–50.0 mg/L had an excellent coefficient of determination of 0.9996. Recovery rate ranged from 82.98 to 95.43% with relative standard deviations ≤5.12% and limits of detection and quantification of 0.003 and 0.01 mg/kg, respectively. The initial deposits [day 0 (2 h post‐application)] were considerably lower (7.57 and 8.55 mg/kg for sites 1 and 2, respectively) than the maximum residue limit (30 mg/kg) set by the Korean Ministry of Food and Drug Safety. The dissipation half‐life was approximately the same, being 5.0 and 5.1 days for sites 1 and 2, respectively. Risk assessment estimated as acceptable daily intake revealed a value of 0.084 or 0.094% (day 0) and 0.014% (10 days post‐application), for sites 1 and 2, respectively. The values indicated that dimethomorph can be safely used on Swiss chard, with no hazardous effects expected for Korean consumers.
Serum galectin‐3 levels and delirium among postpartum intensive care unit women
Authors: Zhu Ying , Hu Wei , Zhu Ming‐Li , Yin Ting , Su Jun , Wang Jian‐Rong
Published: July 2017

Objective

Inflammation correlates with delirium. Galectin‐3 is a proinflammatory protein. This study aimed to determine relation of serum galectin‐3 levels to delirium of postpartum intensive care unit (ICU) women.

Materials and Methods

In this prospective observational study, serum galectin‐3, S100B, and C‐reactive protein levels of 412 postpartum ICU women and 412 healthy women were measured. Delirium and Acute Physiology and Chronic Health Care Evaluation II (APCHCE II) scores were recorded.

Results

Serum levels of galectin‐3, S100B, and C‐reactive protein were significantly elevated in the postpartum women than in the healthy women. Galectin‐3 levels were highly associated with APCHCE II scores and S100B and C‐reactive protein levels. Galectin‐3, C‐reactive protein, and S100B levels and APCHCE II scores were identified as independent predictors for delirium. Area under the curve (AUC) of serum galectin‐3 levels was similar to that of S100B levels, and significantly exceeded those of C‐reactive protein levels and APCHCE II scores. Moreover, galectin‐3 significantly improved the AUCs of APCHCE II scores, S100B levels, and C‐reactive protein levels.

Conclusions

Galectin‐3, involved in inflammatory process underlying delirium‐related brain injury, might be a potential biomarker to predict delirium of postpartum ICU women.