bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthetic Biomaterials to Rival Nature's Complexity—a Path Forward with Combinatorics, High‐Throughput Discovery, and High‐Content Analysis
Authors: Zhang Douglas , Lee Junmin , Kilian Kristopher A. 
Published: August 2017

AbstractCells in tissue receive a host of soluble and insoluble signals in a context‐dependent fashion, where integration of these cues through a complex network of signal transduction cascades will define a particular outcome. Biomaterials scientists and engineers are tasked with designing materials that can at least partially recreate this complex signaling milieu towards new materials for biomedical applications. In this progress report, recent advances in high throughput techniques and high content imaging approaches that are facilitating the discovery of efficacious biomaterials are described. From microarrays of synthetic polymers, peptides and full‐length proteins, to designer cell culture systems that present multiple biophysical and biochemical cues in tandem, it is discussed how the integration of combinatorics with high content imaging and analysis is essential to extracting biologically meaningful information from large scale cellular screens to inform the design of next generation biomaterials.
Reprogrammable Phononic Metasurfaces
Authors: Bilal Osama R. , Foehr André , Daraio Chiara 
Published: August 2017

AbstractPhononic metamaterials rely on the presence of resonances in a structured medium to control the propagation of elastic waves. Their response depends on the geometry of their fundamental building blocks. A major challenge in metamaterials design is the realization of basic building blocks that can be tuned dynamically. Here, a metamaterial plate is realized that can be dynamically tuned by harnessing geometric and magnetic nonlinearities in the individual unit cells. The proposed tuning mechanism allows a stiffness variability of the individual unit cells and can control the amplitude of transmitted excitation through the plate over three orders of magnitude. The concepts can be extended to metamaterials at different scales, and they can be applied in a broad range of engineering applications, from seismic shielding at low frequency to ultrasonic cloaking at higher frequency ranges.
Motion Manipulation of Micro‐ and Nanomotors
Authors: Tu Yingfeng , Peng Fei , Wilson Daniela A. 
Published: August 2017

AbstractInspired by the self‐migration of microorganisms in nature, artificial micro‐ and nanomotors can mimic this fantastic behavior by converting chemical fuel or external energy into mechanical motion. These self‐propelled micro‐ and nanomotors, designed either by top‐down or bottom‐up approaches, are able to achieve different applications, such as environmental remediation, sensing, cargo/sperm transportation, drug delivery, and even precision micro‐/nanosurgery. For these various applications, especially biomedical applications, regulating on‐demand the motion of micro‐ and nanomotors is quite essential. However, it remains a continuing challenge to increase the controllability over motors themselves. Here, we will discuss the recent advancements regarding the motion manipulation of micro‐ and nanomotors by different approaches.
Superior Photocatalytic H2 Production with Cocatalytic Co/Ni Species Anchored on Sulfide Semiconductor
Authors: Zhao Guixia , Sun Yubin , Zhou Wei , Wang Xiangke , Chang Kun , Liu Guigao , Liu Huimin , Kako Tetsuya , Ye Jinhua 
Published: August 2017

AbstractDownsizing transition metal‐based cocatalysts on semiconductors to promote photocatalytic efficiency is important for research and industrial applications. This study presents a novel and facile strategy for anchoring well‐dispersed metal species on CdS surface through controlled decarboxylation of the ethylenediaminetetraacetate (EDTA) ligand in the metal–EDTA (M–EDTA) complex and CdS mixture precursor to function as a cocatalyst in the photocatalytic H2 evolution. Microstructure characterization and performance evaluation reveal that under visible light the resulting pentacoordinated Co(II) and hexacoordinated Ni(II) on CdS exhibits a high activity of 3.1 mmol h−1 (with turnover frequency (TOF) of 626 h−1 and apparent quantum efficiency (AQE) of 56.2% at 420 nm) and 4.3 mmol h−1 (with TOF of 864 h−1 and AQE of 67.5% at 420 nm), respectively, toward cocatalytic hydrogen evolution, and the cocatalytic activity of such a hexacoordinated Ni(II) even exceeds that of platinum. Further mechanistic study and theoretical modeling indicate that the fully utilized Co(II)/Ni(II) active sites, efficient charge transfer, and favorable kinetics guarantee the efficient activities. This work introduces a promising precursor, i.e., M–EDTA for planting well‐dispersed transition metal species on the sulfide supports by a facile wet‐chemistry approach, providing new opportunities for photocatalytic H2 production at the atomic/molecular scale.
Doxorubicin Adsorbed on Carbon Nanotubes: Helical Structure and New Release Trigger
Authors: Sadaf Shamaila , Walder Lorenz 
Published: August 2017

AbstractThe well‐known drug delivery system “doxorubicin physically loaded on carbon nanotubes” (Dox@CNT) is visualized by scanning tunneling microscopy at the molecular level, revealing rich architectural variability of Dox@CNT, and allowing to measure and rationalize reported loading efficiencies (80–200%) for the first time from image analysis. Reduction of Dox@CNT is identified as a so far unknown intrinsic release mechanism of biochemically relevance for Dox from Dox@CNT requiring no further CNT surface modification beside Dox loading. Electron injection into Dox@CNT from an electrode or from the biological reducing agent glutathione (GSH) leads to irreversible release of Dox. Its rate follows a linear free energy relationship (reduction potential vs log (Dox release rate)) with half‐life times from below seconds to hours. With extracellular GSH levels in the micromolar range and intracellular GSH concentrations of 10 × 10−3m or even higher, the findings can explain the preferential intracellular release of Dox from its physically adsorbed state on CNTs. The influence of acidity on the release rate of Dox on pristine 6,5‐CNTs in the absence of GSH is found to be negligible. The experimental findings are strongly supported by semi‐empirical calculations.
Van Der Waals Hybrid Perovskite of High Optical Quality by Chemical Vapor Deposition
Authors: Chen Zhizhong , Wang Yiping , Sun Xin , Guo Yuwei , Hu Yang , Wertz Esther , Wang Xi , Gao Hanwei , Lu Toh‐Ming , Shi Jian 
Published: August 2017

Abstract2D hybrid perovksite (RNH3)2PbX4 materials not only serve as ideal platforms to study fundamental physics such as polariton dynamics but also show promise for optoelectronic and electro‐optic applications. However, for the preparation of high optical quality crystals, mechanical exfoliation has to be applied in the past. In this work, the vapor phase growth of single crystalline (C4H9NH3)2PbI4 flakes with high optical quality is reported. Individual single crystalline domains show lateral size about 5–10 µm with defined rectangular shape. Spectroscopic studies show room temperature photoluminescence full width at half maximum of 70 meV and decay lifetime of several nanoseconds, indicating comparably high quality with mechanically exfoliated counterparts. Exciton binding energy 279 ± 46 meV and electron–phonon coupling strength around 20 meV are revealed. This vacuum‐based method may provide a solution for integrating layered perovskites into optoelectronic devices and systems.
All‐Polymer Photonic Microcavities Doped with Perylene Bisimide J‐Aggregates
Authors: Lova Paola , Grande Vincenzo , Manfredi Giovanni , Patrini Maddalena , Herbst Stefanie , Würthner Frank , Comoretto Davide 
Published: August 2017

AbstractThanks to exciting chemical and optical features, perylene bisimide J‐aggregates are ideal candidates to be employed for high‐performance plastic photonic devices. However, they generally tend to form π–π stacked H‐aggregates that are unsuitable for implementation in polymer resonant cavities. In this work, the efficient compatibilization of a tailored perylene bisimide forming robust J‐aggregated supramolecular polymers into amorphous polypropylene is introduced. The new nanocomposite is then implemented into an all‐polymer planar microcavity, which provides strong and directional spectral redistribution of the J‐aggregate photoluminescence, due to a strong modification of the photonic states. A systematic analysis of the photoemitting processes, including photoluminescence decay and quantum yields, shows that the optical confinement in the polymeric microcavity does not introduce any additional nonradiative de‐excitation pathways to those already found in the J‐aggregate nanocomposite film and pave the way to PBI‐based high‐performance plastic photonic devices.
Maskless Fabrication of Aluminum Nanoparticles for Plasmonic Enhancement of Lead Halide Perovskite Lasers
Authors: Wang Shuai , Fang Jimao , Zhang Chen , Sun Shang , Wang Kaiyang , Xiao Shumin , Song Qinghai 
Published: August 2017

AbstractLead halide perovskite microlasers have been intensively studied in the past few years. While a number of unique laser properties have been demonstrated, the main laser characteristics are determined by the crystal quality and the shapes of synthesized materials. Patterning the semiconductors with plasmonic nanostructures is an effective way to control light emission and absorption. However, due to the instability of perovskites, most of nanofabrication technologies of plasmonic nanostructures will significantly spoil the qualities of perovskite devices. Here the surface plasmon enhanced laser emissions from all‐inorganic lead halide perovskites are experimentally demonstrated. Without using any mask or expensive pattern generations, relatively uniform aluminum nanoparticles (NPs) are deposited onto the top surface of CsPbBr3 perovskites with electron beam evaporation. After the deposition of optimized aluminum NPs, the thresholds of whispering‐gallery‐mode lasers in CsPbBr3 perovskite microrods are significantly reduced by more than 20% and the output intensities of perovskite microlasers are significantly enhanced by more than an order of magnitude via the plasmonic resonances. Considering the simple, controllable, and cost‐effective fabrication process, this research shall route a new avenue to the control of perovskite microlasers and their applications.
Phosphorescent Ionic Iridium(III) Complexes Displaying Counterion‐Dependent Emission Colors for Flexible Electrochromic Luminescence Device
Authors: Ma Yun , Yang Jin , Liu Shujuan , Xia Huiting , She Pengfei , Jiang Rui , Zhao Qiang 
Published: August 2017

AbstractStimulus‐responsive luminescent materials have drawn considerable interest because they are ideal candidates for optoelectronic applications. Herein, a series of phosphorescent iridium(III) complexes [(CZPY)2IrNH]+X− (X− = PF6−, I−, Br−, Cl−) containing two NH moieties in the N^N ligand is reported. These complexes exhibit significantly counterion‐dependent emission color change from green (493 nm) to orange (590 nm) in CH3CN. Besides, the emission color of [(CZPY)2IrNH]+PF6− is sensitive to the external electric field. Upon applying a voltage, the emission color of the complex in solution is changed evidently from orange to green at the cathode within several seconds. Moreover, with the advantages of high ionic conductivity, thermal stability, and mechanical strength, a bisimidazolium‐based polymeric ionic liquid is designed and synthesized as the electrolyte. Ultimately, a flexible electrochromic luminescence device is successfully fabricated, which exhibits excellent performance and properties, such as good flexibility, low operation voltage, fast response time, and good reversibility.
Nickel‐Catalyzed C−N Cross‐Coupling of Primary Imines with Subsequent In Situ [2+2] Cycloaddition or Alkylation
Authors: Power Dennis J. , Jones Kieran D. , Kampmann Sven S. , Flematti Gavin R. , Stewart Scott G. 
Published: August 2017

AbstractHerein, we report a new method for the C−N cross‐coupling of primary imines by using an inexpensive air‐stable nickel catalyst. This procedure allows for a subsequent in situ reaction with moisture‐sensitive reagents. In this study, we also report secondary [2+2] cycloaddition and alkylation reactions. A diverse range of substrates were explored to highlight the usefulness of this combination of reactions. The reaction products from the cycloaddition pathway, through a Staudinger reaction, have potential applications as β‐lactam antibiotics.
Recognition‐then‐Reaction Enables Site‐Selective Bioconjugation to Proteins on Live‐Cell Surfaces
Authors: Cui Cheng , Zhang Hui , Wang Ruowen , Cansiz Sena , Pan Xiaoshu , Wan Shuo , Hou Weijia , Li Long , Chen Meiwan , Liu Yuan , Chen Xigao , Liu Qiaoling , Tan Weihong 
Published: August 2017

AbstractSite‐selective protein modification is a key step in facilitating protein functionalization and manipulation. To accomplish this, genetically engineered proteins were previously required, but the procedure was laborious, complex, and technically challenging. Herein we report the development of aptamer‐based recognition‐then‐reaction to guide site‐selective protein/DNA conjugation in a single step with outstanding selectivity and efficiency. As models, several proteins, including human thrombin, PDGF‐BB, Avidin, and His‐tagged recombinant protein, were studied, and the results showed excellent selectivity under mild reaction conditions. Taking advantage of aptamers as recognition elements with extraordinary selectivity and affinity, this simple preparation method can tag a protein in a complex milieu. Thus, with the aptamer obtained from cell‐SELEX, real‐time modification of live‐cell membrane proteins can be achieved in one step without any pre‐treatment.
Tuning Crystallization Pathways through the Mesoscale Assembly of Biomacromolecular Nanocrystals
Authors: Tao Fei , Han Qian , Liu Kaiqiang , Yang Peng 
Published: August 2017

AbstractMacromolecular crystallization has many implications in biological and materials science. Similar to the crystallization of other molecules, macromolecular crystallization conventionally considers a critical nucleus, followed by crystallographic packing of macromolecules to drive further crystal growth. Herein, we discover a distinctive macromolecular crystallization pathway by developing the concept of a macromolecular mesocrystal. This nonclassical polymer crystallization occurs through the mesoscale self‐assembly of (bio)macromolecular nanocrystals. The new concept for macromolecular crystallization presented herein is fundamental and relevant to many fields, including materials science, chemistry, biomimetics, nanoscience, and structural biology.
Radical Hydrodehalogenation of Aryl Bromides and Chlorides with Sodium Hydride and 1,4‐Dioxane
Authors: Hokamp Tobias , Dewanji Abhishek , Lübbesmeyer Maximilian , Mück‐Lichtenfeld Christian , Würthwein Ernst‐Ulrich , Studer Armido 
Published: August 2017

AbstractA practical method for radical chain reduction of various aryl bromides and chlorides is introduced. The thermal process uses NaH and 1,4‐dioxane as reagents and 1,10‐phenanthroline as an initiator. Hydrodehalogenation can be combined with typical cyclization reactions, proving the nature of the radical mechanism. These chain reactions proceed by electron catalysis. DFT calculations and mechanistic studies support the suggested mechanism.
Release of Enzymatically Active Deubiquitinating Enzymes upon Reversible Capture by Disulfide Ubiquitin Reagents
Authors: de Jong Annemieke , Witting Katharina , Kooij Raymond , Flierman Dennis , Ovaa Huib 
Published: August 2017

AbstractDeubiquitinating enzymes (DUBs) catalyze the cleavage of ubiquitin from target proteins. Ubiquitin is post‐translationally attached to proteins and serves as an important regulatory signal for key cellular processes. In this study, novel activity‐based probes to study DUBs were synthesized that comprise a ubiquitin moiety and a novel disulfide warhead at the C‐terminus. These reagents can bind DUBs covalently by forming a disulfide bridge between the active‐site cysteine residue and the ubiquitin‐based probe. As disulfide bridges can be broken by the addition of a reducing agent, these novel ubiquitin reagents can be used to capture and subsequently release catalytically active DUBs, whereas existing capturing agents bind irreversibly. These novel reagents allow for the study of these enzymes in their active state under various conditions.
Characterization of the RhI/dppe‐Catalyzed Ring Expansion of 2‐Alkyl‐Benzocyclobutenones by DFT Calculations
Authors: Qin Hua‐Li , Zhao Chuang , Leng Jing , Kantchev Eric Assen B. 
Published: August 2017

AbstractThe [(dppe)RhCl]‐catalysed ring expansion of 2‐methylbenzocyclobutenone has been proposed to occur by C−C oxidative addition to rhodaindanone, β‐hydride elimination, hydrorhodation and C−C reductive elimination. DFT calculations [IEFPCM(1,4‐dioxane, 383.15 K)/PBE0/DGDZVP level of theory] here confirm this mechanism. As proposed, oxidative addition into CHMe−CO bond is preferred over the alternative CHMe‐aryl insertion. The barriers of oxidative addition, β‐hydride elimination hydrorhodation, and reductive elimination are 23.6 (rate‐determining), 8.9, 10.4, and 13.1 kcal mol−1, respectively. Therefore, the β‐hydride elimination/hydrorhodation steps to/from an octahedral RhIII‐hydride serve as a fast equilibrating hydrogen shuffle flanking the two slower C−C bond breaking/making steps. This is consistent with the weak kinetic isotope effect observed experimentally when 2‐CH3 and 2‐CD3benzocyclobutenone react competitively in a 1:1 ratio. The reaction barriers calculated with more modern, dispersion interaction‐corrected methods (SMD/M06 and IEFPCM/ωB97xD) follow identical trends.
Effect of time to initiation of postoperative radiation therapy on survival in surgically managed head and neck cancer
Authors: Graboyes Evan M. , Garrett‐Mayer Elizabeth , Ellis Mark A. , Sharma Anand K. , Wahlquist Amy E. , Lentsch Eric J. , Nussenbaum Brian , Day Terry A. 
Published: August 2017

BACKGROUNDThe objective of this study was to determine the effects of National Comprehensive Cancer Network (NCCN) guideline–adherent initiation of postoperative radiation therapy (PORT) and different time‐to‐PORT intervals on the overall survival (OS) of patients with head and neck squamous cell carcinoma (HNSCC).METHODSThe National Cancer Data Base was reviewed for the period of 2006‐2014, and patients with HNSCC undergoing surgery and PORT were identified. Kaplan‐Meier survival estimates, Cox regression analysis, and propensity score matching were used to determine the effects of initiating PORT within 6 weeks of surgery and different time‐to‐PORT intervals on survival.RESULTSThis study included 41,291 patients. After adjustments for covariates, starting PORT >6 weeks postoperatively was associated with decreased OS (adjusted hazard ratio [aHR], 1.13; 99% confidence interval [CI], 1.08‐1.19). This finding remained in the propensity score–matched subset (hazard ratio, 1.21; 99% CI, 1.15‐1.28). In comparison with starting PORT 5 to 6 weeks postoperatively, initiating PORT earlier was not associated with improved survival (aHR for ≤ 4 weeks, 0.93; 99% CI, 0.85‐1.02; aHR for 4‐5 weeks, 0.92; 99% CI, 0.84‐1.01). Increasing durations of delay beyond 7 weeks were associated with small, progressive survival decrements (aHR, 1.09, 1.10, and 1.12 for 7‐8, 8‐10, and >10 weeks, respectively).CONCLUSIONSNonadherence to NCCN guidelines for initiating PORT within 6 weeks of surgery was associated with decreased survival. There was no survival benefit to initiating PORT earlier within the recommended 6‐week timeframe. Increasing durations of delay beyond 7 weeks were associated with small, progressive survival decrements. Cancer 2017;123:4841‐50. © 2017 American Cancer Society.
Inhibiting heat shock protein 90 and the ubiquitin‐proteasome pathway impairs metabolic homeostasis and leads to cell death in human pancreatic cancer cells
Authors: Belalcazar Astrid , Shaib Walid L. , Farren Matthew R. , Zhang Chao , Chen Zhengjia , Yang Lily , Lesinski Gregory B. , El‐Rayes Bassel F. , Nagaraju Ganji Purnachandra 
Published: August 2017

BACKGROUNDHeat shock protein 90 (HSP90) and the ubiquitin‐proteasome pathway play crucial roles in the homeostasis of pancreatic cancer cells. This study combined for the first time the HSP90 inhibitor ganetespib (Gan) and the proteasome inhibitor carfilzomib (Carf) to target key mechanisms of homeostasis in pancreatic cancer. It was hypothesized that Gan plus Carf would elicit potent antitumor activity by modulating complementary homeostatic processes.METHODSIn vitro and in vivo effects of this combination on mechanisms of cell growth and viability were evaluated with human pancreatic cancer cell lines (MIA PaCa‐2 and HPAC).RESULTSCombined treatment with Gan and Carf significantly decreased cell viability. The mechanism varied by cell line and involved G2‐M cell‐cycle arrest accompanied by a consistent reduction in key cell‐cycle regulatory proteins and concomitant upregulation of p27. Further studies revealed increased autophagy markers, including the upregulation of autophagy related 7 and light chain 3 cleavage, and evidence of apoptosis (increased Bax expression and processing of caspase 3). Immunoblot analyses confirmed the modulation of other pathways that influence cell viability, including phosphoinositide 3‐kinase/Akt and nuclear factor κB. Finally, the treatment of athymic mice bearing HPAC tumors with Gan and Carf significantly reduced tumor growth in vivo. An immunoblot analysis of freshly isolated tumors from animals at the end of the study confirmed in vivo modulation of key signaling pathways.CONCLUSIONSThe results reveal Gan plus Carf to be a promising combination with synergistic antiproliferative, apoptotic, and pro‐autophagy effects in preclinical studies of pancreatic cancer and will further the exploration of the utility of this treatment combination in clinical trials. Cancer 2017;123:4924‐33. © 2017 American Cancer Society.
Digitally reconstructing Van Gogh'sField with Irises near Arles.Part 2: Pigment concentration maps
Authors: Kirchner Eric , van der Lans Ivo , Ligterink Frank , Geldof Muriel , Ness Proano Gaibor Art , Hendriks Ella , Janssens Koen , Delaney John 
Published: August 2017

AbstractColors in many paintings of great art historical value have changed over time, due to the combined effects of natural ageing, accumulated surface grime, and materials added during later conservation treatments. The physical restoration of the colors in such paintings is not possible. This article describes one part of work done to digitally restore the colors of Van Gogh's paintingField with Irises near Arles, dating from May 1888. We have used multispectral reflectance data to estimate absorption K and backscattering S parameters of Kubelka‐Munk 2‐constant theory. This was done for all 13 pigments known to have been used by Van Gogh in this painting, and based on this the concentration maps for each of these pigments were calculated. We validated the calculated concentration maps in several ways. For some pigments, we were able to predict spots on the painting where the pigment is expected to occur in unmixed form based on visual examination. For several other pigments, the concentration maps could be shown to agree with XRF data. Finally, for some other pigments the concentration maps were supported by additional evidence from microscopic examinations, remarks in Van Gogh's letters and from early color reproductions. For the 1.7 million pixels for which multispectral data is available, the average color difference between the calculated and measured spectral reflectance curves is CIEDE2000 = 1.05. This further confirms that the Kubelka‐Munk calculations are well suited to describe the variety of spectral reflectance on the painting.