bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemically Induced Pheochromocytomas in Rats: Mechanisms and Relevance for Human Risk Assessment [MAK Value Documentation, 2010]
Authors: Greim H. , Hartwig A. ,   MAK Commission
Published: October 2016

Pheochromocytomas are tumors originating from chromaffin cells of the adrenal medulla, which have been observed in numerous carcinogenicity studies. We have evaluated their concurrence with other effects and the possible mechanisms to assess the relevance of such data for the classification of carcinogenic effects and their relevance to humans. The evaluation revealed that pheochromocytomas occur with relative frequency in male rats, especially when the following conditions are involved: hypoxia, uncoupling of oxidative phosphorylation, disturbance in calcium homeostasis, disturbance of the hypothalamic endocrine axis. The underlying biochemical mechanisms suggest that other substances that interfer with these biochemical endpoints also produce pheochromocytomas. Such endpoints include enzymes involved in catecholamine synthesis, receptor tyrosine kinase (RET), hypoxia‐inducible factor (HIF), succinate dehydrogenase, fumarate hydratase, pyruvate dehydrogenase. To date there is no indication that the substances inducing pheochromocytomas in animal experiments also induce corresponding tumors in humans. Since the mechanisms of action identified in rats are to be expected in humans, pheochromocytomas may be induced after exposure conditions similar to those used in the animal studies. Whether hereditary mutations represent a risk factor in humans is not clear. Pheochromocytomas that occur in animal experiments currently appear to have little relevance for conditions at the work place. When sufficiently documented and evaluated, such secondary pheochromocytomas are not relevant for classification and human risk assessment.
Micropatterned Down‐Converting Coating for White Bio‐Hybrid Light‐Emitting Diodes
Authors: Niklaus Lukas , Tansaz Samira , Dakhil Haider , Weber Katharina T. , Pröschel Marlene , Lang Martina , Kostrzewa Monika , Coto Pedro B. , Detsch Rainer , Sonnewald Uwe , Wierschem Andreas , Boccaccini Aldo R. , Costa Rubén D.
Published: October 2016

White hybrid light‐emitting diodes (WHLEDs) are considered as a solid approach toward environmentally sustainable lighting sources that meet the “Green Photonics” requirements. Here, WHLEDs with protein‐based down‐converting coatings, i.e., Bio‐WHLEDs, are demonstrated and exhibit worthy white color quality, luminous efficiency, and stability values. The coatings feature a multilayered cascade‐like architecture with thicknesses of 1–3 mm. This limits the efficiency due to the low optical transmittance. Thus, submillimeter coatings, where the location of the proteins is well‐defined, are highly desired. It is in this context where the thrust of this work sets in. Here, a straightforward way to design microstructured single‐layer coatings, in which the proteins are placed at our command by using 3D printing, is presented. Based on comprehensive spectroscopic and rheological investigations, the optimization of the matrix and the plotting to prepare different micropatterns, i.e., lines, open‐grids, and closed‐grids, is rationalized. The latter are applied to prepare Bio‐WHLEDs with ≈5‐fold enhancement of the luminous efficiency compared to the reference devices with a cascade‐like coating, without losing stability and color quality. As such, this work shows a new route to exploit proteins for optoelectronics, setting a new avenue of research into the emerging field of Bio‐WHLEDs.
Spin Crossover of Yb2+ in CsCaX3 and CsSrX3 (X = Cl, Br, I) – A Guideline to Novel Halide‐Based Scintillators
Authors: Suta Markus , Wickleder Claudia
Published: October 2016

In this paper, the temperature dependence of the photoluminescence of Yb2+ doped into the halidoperovskites CsMX3 (M = Ca, Sr; X = Cl, Br, I) is presented. Yb2+ shows spin‐forbidden high‐spin (HS) and spin‐allowed low‐spin (LS) emission bands in all compounds. Upon excitation of the higher energetic LS transition, very different behaviors of the interplay of the two emissive transitions are observed. In the chlorides, the HS‐based emission becomes already dominant at higher temperatures than 50 K; in the bromides, a temperature‐dependent population of the HS state is observed at higher temperatures than 200 K, whereas in the iodides, the LS emission remains dominant even above 300 K. A vibrational relaxation model is attempted for the explanation of this behavior that reveals a very delicate dependence on the mode energies of the [YbX6]4− octahedra. FIR spectra of the pure Yb2+‐based compounds CsYbX3 are also presented to experimentally verify the estimated average mode energies from the model. Finally, the relevance for novel Yb2+‐based scintillators is discussed.
Superhydrophilic Coating Induced Temporary Conductivity for Low‐Cost Coating and Patterning of Insulating Surfaces
Authors: Zheng Shuang , Wang Dianyu , Tian Ye , Jiang Lei
Published: October 2016

Superhydrophilic surfaces have attracted attention from more and more fields. Here, based on superhydrophilic coatings, insulating substrates are made temporarily conductive and suited for electrostatic powder coating (EPC). Furthermore, by manipulating surface wettability of the substrate, epoxy‐polyester powder particles are directly assembled into patterns in air under electrostatic attraction. First, electrically insulating substrates are treated to be superhydrophilic with composite nanoparticles of TiO2and SiO2. Water droplets sprayed onto the surface could spread completely and connect together to form uniform thin water films (40 μm). The liquid films make the insulating surfaces conductive enough for EPC, which is an environmentally friendly coating process widely applied to conductive workpieces, such as metals. The first pass transfer efficiency (FPTE) is promoted to more than 80%, which is equal to or even greater than those of metal workpieces. Second, FPTE is quite different on surfaces with different wettability. Negatively charged epoxy‐polyester powder particles are attracted toward positively charged water film formed on superhydrophilic coatings. And few powders deposit on untreated nonconductive areas. Compared with electrostatic self‐assembly in solutions, this strategy is suited for rapid assembling various kinds of particles into large area patterns.
Visible‐Light Excited Luminescent Thermometer Based on Single Lanthanide Organic Frameworks
Authors: Li Liang , Zhu Yali , Zhou Xinhui , Brites Carlos D. S. , Ananias Duarte , Lin Zhi , Paz Filipe A. Almeida , Rocha João , Huang Wei , Carlos Luís D.
Published: October 2016

Isostructural lanthanide organic frameworks (Me2NH2)3[Ln3(FDC)4(NO3)4]·4H2O (Ln = Eu (1), Gd (2), Tb (3), H2FDC = 9‐fluorenone‐2,7‐dicarboxylic acid), synthesized under solvothermal conditions, feature a Ln‐O‐C rod‐packing 3D framework. Time‐resolved luminescence studies show that in 1 the energy difference between the H2FDC triplet excited state (17794 cm−1) and the 5D0 Eu3+ level (17241 cm−1) is small enough to allow a strong thermally activated ion‐to‐ligand back energy transfer. Whereas the emission of the ligand is essentially constant the 5D0→7F2 intensity is quenched when the temperature increases from 12 to 320 K, rendering 1 the first single‐lanthanide organic framework ratiometric luminescent thermometer based on ion‐to‐ligand back energy transfer. More importantly, this material is also the first example of a metal organic framework thermometer operative over a wide temperature range including the physiological (12‐320 K), upon excitation with visible light (450 nm).
A Multiresponsive Anisotropic Hydrogel with Macroscopic 3D Complex Deformations
Authors: Ma Chunxin , Le Xiaoxia , Tang Xinlei , He Jiang , Xiao Peng , Zheng Jing , Xiao He , Lu Wei , Zhang Jiawei , Huang Youju , Chen Tao
Published: October 2016

As one of the most promising smart materials, stimuli‐responsive polymer hydrogels (SPHs) can reversibly change volume or shape in response to external stimuli. They thus have shown promising applications in many fields. While considerable progress of 2D deformation of SPHs has been achieved, the realization of 3D or even more complex deformation still remains a significant challenge. Here, a general strategy towards designing multiresponsive, macroscopically anisotropic SPHs (MA‐SPHs) with the ability of 3D complex deformations is reported. Through a local UV‐reduction of graphene oxide sheets (GOs) with a patterned fashion in the GO‐poly(N‐isopropylacrylamide) (GO‐PNIPAM) composite hydrogel sheet, MA‐SPHs can be achieved after the introduction of a second poly(methylacrylic acid) network in the unreduced part of GO‐PNIPAM hydrogel sheet. The resulting 3D MA‐SPHs can provide remote‐controllable light‐driven, as well as thermo‐, pH‐, and ionic strength‐triggered multiresponsive 3D complex deformations. Approaches in this study may provide new insights in designing and fabricating intelligent soft materials for bioinspired applications.
Advanced Lithium–Sulfur Batteries Enabled by a Bio‐Inspired Polysulfide Adsorptive Brush
Authors: Zhao Teng , Ye Yusheng , Peng Xiaoyu , Divitini Giorgio , Kim Hyun‐Kyung , Lao Cheng‐Yen , Coxon Paul R. , Xi Kai , Liu Yingjun , Ducati Caterina , Chen Renjie , Kumar R. Vasant
Published: October 2016

Issues with the dissolution and diffusion of polysulfides in liquid organic electrolytes hinder the advance of lithium–sulfur batteries for next‐generation energy storage. To trap and re‐utilize the polysulfides without hampering lithium ion conductivity, a bio‐inspired, brush‐like interlayer consisting of zinc oxide (ZnO) nanowires and interconnected conductive frameworks is proposed. The chemical effect of ZnO on capturing polysulfides has been conceptually confirmed, initially by using a commercially available macroporous nickel foam as a conductive backbone, which is then replaced by a free‐standing, ultra‐light micro/mesoporous carbon (C) nanofiber mat for practical application. Having a high sulfur loading of 3 mg cm−2, the sulfur/multi‐walled carbon nanotube composite cathode with a ZnO/C interlayer exhibits a reversible capacity of 776 mA h g−1 after 200 cycles at 1C with only 0.05% average capacity loss per cycle. A good cycle performance at a high rate can be mainly attributed to the strong chemical bonding between ZnO and polysulfides, fast electron transfer, and an optimized ion diffusion path arising from a well‐organized nanoarchitecture. These results herald a new approach to advanced lithium–sulfur batteries using brush‐like chemi‐functional interlayers.
A Fluorinated Bola‐Amphiphilic Dendrimer for On‐Demand Delivery of siRNA, via Specific Response to Reactive Oxygen Species
Authors: Liu Xiaoxuan , Wang Yang , Chen Chao , Tintaru Aura , Cao Yu , Liu Juan , Ziarelli Fabio , Tang Jingjie , Guo Hongbo , Rosas Roseline , Giorgio Suzanne , Charles Laurence , Rocchi Palma , Peng Ling
Published: October 2016

Functional materials capable of responding to stimuli intrinsic to diseases are extremely important for specific drug delivery at the disease site. However, developing on‐demand stimulus‐responsive vectors for targeted delivery is highly challenging. Here, a stimulus‐responsive fluorinated bola‐amphiphilic dendrimer is reported for on‐demand delivery of small interfering RNA (siRNA) in response to the characteristic high level of reactive oxygen species (ROS) in cancer cells. This dendrimer bears a ROS‐sensitive thioacetal in the hydrophobic core and positively charged poly(amidoamine) dendrons at the terminals, capable of interacting and compacting the negatively charged siRNA into nanoparticles to protect the siRNA and promote cellular uptake. The ROS‐sensitive feature of this dendrimer boosts specific and efficient disassembly of the siRNA/vector complexes in ROS‐rich cancer cells for effective siRNA delivery and gene silencing. Moreover, the fluorine tags in the vector enable 19F‐NMR analysis of the ROS‐responsive delivery process. In addition, this ingenious and distinct bola‐amphiphilic dendrimer is also able to combine the advantageous delivery features of both lipid and dendrimer vectors. Therefore, it represents an innovative on‐demand stimulus‐responsive delivery platform.
Chemical Blowing Approach for Ultramicroporous Carbon Nitride Frameworks and Their Applications in Gas and Energy Storage
Authors: Talapaneni Siddulu Naidu , Lee Ji Hoon , Je Sang Hyun , Buyukcakir Onur , Kwon Tae‐woo , Polychronopoulou Kyriaki , Choi Jang Wook , Coskun Ali
Published: October 2016

A scalable, template‐free synthetic strategy is presented for the preparation of ultramicroporous carbon nitride frameworks (CNFs) through a chemical blowing approach by using ammonium chloride as blowing agent and hexamethylene tetraamine as the C and N precursor and a subsequent potassium hydroxide chemical activation is employed to obtain CNFs with surface areas up to 1730 m2 g−1 along with a high nitrogen content of 13.3 wt%. CNFs showed CO2 uptake capacities up to 5.74 mmol g−1 at 1 bar and 1.67 mmol g−1 at 0.15 bar, 273 K along with a very high CO2/N2 selectivity. In addition, H2 uptake capacity of 1.9 wt% and the isosteric heats of adsorption (Qst) value of 9.0 kJ mol−1 at zero coverage have been also observed. Moreover, the presence of nitrogen‐doped graphene walls in CNFs also facilitated their application as supercapacitors, with capacitance values up to ≈114 F g−1 at 0.5 A g−1, along with a good cyclability and capacitance retention. This approach effectively extends unique surface properties of carbon nitrides into the micropore regime for effective capture of small gases and energy storage applications. Importantly, textural properties of CNFs can be simply tuned by judicious choice of organic precursors and the blowing agent.
Micro–Nanocomposites in Environmental Management
Authors: Chen Dongyun , Zhu Haiguang , Yang Shun , Li Najun , Xu Qingfeng , Li Hua , He Jinghui , Lu Jianmei
Published: October 2016

Water pollution, a worldwide issue for the human society, has raised global concerns on environmental sustainability, calling for high‐performance materials for effective treatments. Since the traditional techniques have inherent limitations in treatment speed and efficiency, nanotechnology is subsequently used as an environmental technology to remove pollutants through a rapid adsorption and degradation process. Therefore, here, various adsorbent and photodegradation composite materials leading to effective water remediation are summarized and predicted. Notably, recent advances in simultaneous adsorption and photodegradation micro–nanocomposites are outlined. Such materials can not only completely adsorb and remove contaminants, but the micro–nanocomposites can also be directly reused without further treatment. Finally, the future development of this unique system is discussed.
Control of Mesoscale Morphology and Photovoltaic Performance in Diketopyrrolopyrrole‐Based Small Band Gap Terpolymers
Authors: Ye Long , Jiao Xuechen , Zhang Shaoqing , Yao Huifeng , Qin Yunpeng , Ade Harald , Hou Jianhui
Published: October 2016

Morphology control is one of the key strategies in optimizing the performance of organic photovoltaic materials, particularly for diketopyrrolopyrrole (DPP)‐based donor polymers. The design of DPP‐based polymers that provide high power conversion efficiency (PCE) presents a significant challenge that requires optimization of both energetics and morphology. Herein, a series of high performance, small band gap DPP‐based terpolymers are designed via two‐step side chain engineering, namely introducing alternating short and long alkyls for reducing the domain spacing and inserting alkylthio for modulating the energy levels. The new DPP‐based terpolymers are compared to delineate how the side chain impacts the mesoscale morphology. By employing the alkylthio‐substituted terpolymer PBDPP‐TS, the new polymer solar cell (PSC) device realizes a good balance of a high Voc of 0.77 V and a high Jsc over 15 mA cm−2, and thus realizes desirable PCE in excess of 8% and 9.5% in single junction and tandem PSC devices, respectively. The study indicates better control of domain purity will greatly improve performance of single junction DPP‐based PSCs toward 10% efficiency. More significantly, the utility of this stepwise side chain engineering can be readily expanded to other classes of well‐defined copolymers and triggers efficiency breakthroughs in novel terpolymers for photovoltaic and related electronic applications.
Electrocatalytic Oxygen Evolution Reaction in Acidic Environments – Reaction Mechanisms and Catalysts
Authors: Reier Tobias , Nong Hong Nhan , Teschner Detre , Schlögl Robert , Strasser Peter
Published: October 2016

The low efficiency of the electrocatalytic oxidation of water to O2 (oxygen evolution reaction‐OER) is considered as one of the major roadblocks for the storage of electricity from renewable sources in form of molecular fuels like H2 or hydrocarbons. Especially in acidic environments, compatible with the powerful proton exchange membrane (PEM), an earth‐abundant OER catalyst that combines high activity and high stability is still unknown. Current PEM‐compatible OER catalysts still rely mostly on Ir and/or Ru as active components, which are both very scarce elements of the platinum group. Hence, the Ir and/or Ru amount in OER catalysts has to be strictly minimized. Unfortunately, the OER mechanism, which is the most powerful tool for OER catalyst optimization, still remains unclear. In this review, we first summarize the current state of our understanding of the OER mechanism on PEM‐compatible heterogeneous electrocatalysts, before we compare and contrast that to the OER mechanism on homogenous catalysts. Thereafter, an overview over monometallic OER catalysts is provided to obtain insights into structure‐function relations followed by a review of current material optimization concepts and support materials. Moreover, missing links required to complete the mechanistic picture as well as the most promising material optimization concepts are pointed out.
Ornamental Plants in the United States: An Econometric Analysis of a Household‐Level Demand System
Authors: Hovhannisyan Vardges , Khachatryan Hayk
Published: October 2016

This study provides an empirical analysis of demand for a large group of ornamental plants using a theory‐based demand model. Specifically, consumer preferences are represented by the Almost Ideal Demand System where allowance is made for demand censoring. Given that revealed‐preference data are usually limited to certain ornamental plants and geographical locations, we exploit unique hypothetical purchase data collected via an online survey regarding 16 annual, perennial, and foliage plants from across the United States. The effect of various socio‐economic and demographic factors on demand for plants is quantified. Our findings indicate that ornamental plants are predominantly price‐elastic with foliage plants being more price‐responsive vis‐a‐vis other plant categories. Further, a majority of plants are expenditure‐elastic with the estimates of foliage plants manifesting the greatest variability. Finally, plants in the same category appear to be closer substitutes. Results benefit ornamental plant industry stakeholders as they determine the best pricing strategies in their specific markets.
Synthetic Routes to Thiol‐Functionalized Organic Semiconductors for Molecular and Organic Electronics
Authors: Operamolla Alessandra , Punzi Angela , Farinola Gianluca M.
Published: October 2016

Over the few last decades, the potential of using thiol functionalities to induce the self‐assembly of various kinds of molecules on metal surfaces has been widely demonstrated. In particular, π‐conjugated molecules can undergo self‐assembly on metallic surfaces to create electroactive supramolecular layers, which have found important applications in organic and molecular electronics. For this reason, the synthesis of thiol‐functionalized conjugated molecules has been the object of extensive research and many routes have been developed for their synthesis. This Focus Review provides an overview of the state‐of‐the‐art methods for the syntheses of organic semiconductors that are decorated with pendant thiol groups for applications in self‐assembly and molecular and organic electronics. Particular attention is given to synthetic strategies based on organometallic cross‐coupling reactions for the preparation of compounds with extended conjugation.
Total Synthesis of Camptothecin and Related Natural Products by a Flexible Strategy
Authors: Li Ke , Ou Jinjie , Gao Shuanhu
Published: October 2016

A flexible strategy for constructing natural products containing indolizinone or quinolizinone scaffolds and their analogues was developed, which was based on a cascade exo hydroamination followed by spontaneous lactamization. This method was applied in the total synthesis of camptothecin in nine steps in a new ring‐forming approach. It was also used to efficiently prepare five biogenetically or structurally related natural alkaloids, including 22‐hydroxyacuminatine, oxypalmatine, norketoyobyrine, naucleficine, and nauclefine, as well as 35 natural‐product‐like molecules. We believe that this method and the small‐molecule library prepared with it can open new avenues for studying the bioactivity of camptothecin and Nauclea natural products.
Mild and Selective Cobalt‐Catalyzed Chemodivergent Transfer Hydrogenation of Nitriles
Authors: Shao Zhihui , Fu Shaomin , Wei Mufeng , Zhou Shaolin , Liu Qiang
Published: October 2016

Herein, we describe a selective cobalt‐catalyzed chemodivergent transfer hydrogenation of nitriles to synthesize primary, secondary, and tertiary amines. The solvent effect plays a key role for the selectivity control. The general applicability of this procedure was highlighted by the synthesis of more than 70 amine products bearing various functional groups in high chemoselectivity. Moreover, this mild system achieved >2000 TONs (turnover numbers) for the transfer hydrogenation of nitriles.
Regio‐ and Stereoselective Homologation of 1,2‐Bis(Boronic Esters): Stereocontrolled Synthesis of 1,3‐Diols and Sch 725674
Authors: Fawcett Alexander , Nitsch Dominik , Ali Muhammad , Bateman Joseph M. , Myers Eddie L. , Aggarwal Varinder K.
Published: October 2016

1,2‐Bis(boronic esters), derived from the enantioselective diboration of terminal alkenes, can be selectively homologated at the primary boronic ester by using enantioenriched primary/secondary lithiated carbamates or benzoates to give 1,3‐bis(boronic esters), which can be subsequently oxidized to the corresponding secondary‐secondary and secondary‐tertiary 1,3‐diols with full stereocontrol. The transformation was applied to a concise total synthesis of the 14‐membered macrolactone, Sch 725674. The nine‐step synthetic route also features a novel desymmetrizing enantioselective diboration of a divinyl carbinol derivative and high‐yielding late‐stage cross‐metathesis and Yamaguchi macrolactonization reactions.
[Cu13{S2CNnBu2}6(acetylide)4]+: A Two‐Electron Superatom
Authors: Chakrahari Kiran Kumarvarma , Liao Jian‐Hong , Kahlal Samia , Liu Yu‐Chiao , Chiang Ming‐Hsi , Saillard Jean‐Yves , Liu C. W.
Published: October 2016

The first structurally characterized copper cluster with a Cu13 centered cuboctahedral arrangement, a model of the bulk copper fcc structure, was observed in [Cu13(S2CNnBu2)6(C≡CR)4](PF6) (R=C(O)OMe, C6H4F) nanoclusters. Four of the eight triangular faces of the cuboctahedron are capped by acetylide groups in μ3 fashion, and each of the six square faces is bridged by a dithiolate ligand in μ2,μ2 fashion, which leads to a truncated tetrahedron of twelve sulfur atoms. DFT calculations are fully consistent with the description of these Cu13 clusters as two‐electron superatoms, that is, a [Cu13]11+ core passivated by ten monoanionic ligands, with an a1 HOMO containing two 1S jellium electrons.
(C6F5)3B Catalyzed Chemoselective and ortho‐Selective Substitution of Phenols with α‐Aryl α‐Diazoesters
Authors: Yu Zhunzhun , Li Yongfeng , Shi Jiameng , Ma Ben , Liu Lu , Zhang Junliang
Published: October 2016

The development of an efficient method for the site‐selective substitution of unprotected phenols has long been considered as an attractive but challenging task. Herein, we describe a highly chemo‐ and ortho‐selective substitution reaction of phenols with α‐aryl α‐diazoacetates with commercially available (C6F5)3B as the catalyst. This reaction proceeds under simple and mild conditions with high efficiency, it features a wide substrate scope and can be easily scaled up.
Substrate‐Modulated Reductive Graphene Functionalization
Authors: Schäfer Ricarda A. , Weber Konstantin , Koleśnik‐Gray Maria , Hauke Frank , Krstić Vojislav , Meyer Bernd , Hirsch Andreas
Published: October 2016

Covalently functionalizing mechanical exfoliated mono‐ and bilayer graphenides with λ‐iodanes led to the discovery that the monolayers supported on a SiO2 substrate are considerably more reactive than bilayers as demonstrated by statistical Raman spectroscopy/microscopy. Supported by DFT calculations we show that ditopic addend binding leads to much more stable products than the corresponding monotopic reactions as a result of the much lower lattice strain of the reactions products. The chemical nature of the substrate (graphene versus SiO2) plays a crucial role.
Long chain branched poly(butylene succinate‐co‐terephthalate) copolyesters using pentaerythritol as branching agent: Synthesis, thermo‐mechanical, and rheological properties
Authors: Lu Jing , Wu Linbo , Li Bo‐Geng
Published: October 2016

Incorporating long chain branching (LCB) structure into biodegradable copolyesters can effectively improve their melt strength and film blowing processability. However, branching also results in deterioration of crystallizability which is also important for copolyester properties and processing. In this study, pentaerythritol (PER) was used as branching agent (BA) instead of previous used in‐situ BA, diglycidyl 1,2,3,6‐tetrahydrophthalate (DGT), to synthesize LCB poly(butylene succinate‐co‐terephthalate) (PBST) copolyesters. The chain structure was characterized and the effects of branching on thermal transition, mechanical, and rheological properties were investigated. Similar to DGT, copolymerizing small amount of PER (0.1–0.4 mol %) generates LCB structure and, therefore, improves the melt elasticity or strength and tensile modulus but reduces the elongation at break. Differing from DGT, PER showed higher branching efficiency, and PER‐branched PBSTs exhibited unchanged or even improved crystallization ability compared with linear PBST. The improved melt strength coupled with good crystallizability will endow PER‐branched PBSTs with better film blowing processability. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2017,134, 44544.
Molecular imprinting of dibenzothiophene using vinyl pyridine monomers: Fabrication and performance
Authors: Chen Li , Sun Hui , Zhong Yonghui , Zhang Kaiyu , Zheng Tiantian , Lin Ligang , Cheng Bowen
Published: October 2016

Molecular imprinting process was proposed for the sulfur removal from fuels. The novel network‐structured molecularly imprinted polymers (MIPs) were fabricated by arranging 4‐vinyl pyridine functional monomers around dibenzothiophene template compounds, and fixing them with ethylene glycol dimethacrylate as crosslinking agent. The effects of dispersed phase, washing after treatment, content of template molecule, and crosslinking agent on the recognition ability of MIPs have been investigated. The practical performance is obtained by the FT‐IR, morphology, and thermal analysis as well as the recognition ability for dibenzothiophene under various feed sulfur concentrations and recognition time. The recognition ability of MIPs under 1000 mg/L feed sulfur concentration was 4.53 mg S/g. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44552.
Pebax–polydopamine microsphere mixed‐matrix membranes for efficient CO2 separation
Authors: Liu Yuanyuan , Li Xueqin , Qin Yun , Guo Ruili , Zhang Jianshu
Published: October 2016

Novel facilitated‐transport mixed‐matrix membrane (MMM) were prepared through the incorporation of polydopamine (PDA) microspheres into a poly(amide‐b‐ethylene oxide) (Pebax MH 1657) matrix to separate CO2–CH4 gas mixtures. The Pebax–PDA microsphere MMMs were characterized by Fourier transform infrared spectroscopy, scanning electron microcopy, X‐ray diffraction, differential scanning calorimetry, and thermogravimetric analysis. The PDA microspheres acted as an adhesive filler and generated strong interfacial interactions with the polymer matrix; this generated a polymer chain rigidification region near the polymer–filler interface. Polymer chain rigidification usually results in a larger resistance to the transport of gas with a larger molecular diameter and a higher CO2–CH4 selectivity. In addition, the surface of PDA microspheres contained larger numbers of amine, imine, and catechol groups; these were beneficial to the improvement of the CO2 separation performance. Compared with the pristine Pebax membrane, the MMM with a 5 wt % PDA microsphere loading displayed a higher gas permeability and selectivity; their CO2 permeability and CO2–CH4 selectivity were increased by 61 and 60%, respectively, and surpassed the 2008 Robeson upper bound line. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44564.
Synthesis of CNT‐polyurethane nanocomposites using ester‐based polyols with different molecular structure: Mechanical, thermal, and electrical properties
Authors: Shamsi Ramin , Mahyari Mojtaba , Koosha Mojtaba
Published: October 2016

Polyurethanes (PUs) were prepared by in situ polymerization of three diisocyanate with three synthesized low cost ester‐based polyols. The effect of diisocyanate type, diol structure, and molar ratio of diisocyanate to polyol on the mechanical properties was examined and the optimum chemical structure was introduced regarding the superior mechanical properties. Also, in presence of well dispersed hydroxylated multiwalled carbon nanotubes (CNT), PU/CNT nanocomposites were synthesized and fully characterized. The results showed that PU synthesized based on 1,4‐butane diol (BDO) has the best mechanical properties and thermal stability. Also, the PU samples synthesized from 1,6‐hexamethylene diisocyanate (HDI) were more profitable than aromatic diisocyanate structures due to higher crystallinity and microstructure packing. The nanocomposite sample containing 1.5% CNT was the optimum composition for the maximum tensile strength and electrical conductivity. This result was related to the uniform dispersion and bonding of CNTs to PU chains at this composition, while aggregates were formed at higher concentration of CNTs which increased the defects and reduced the uniformity of the structure. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44567.
Upgrading Electroresistive Memory from Binary to Ternary Through Single‐Atom Substitution in the Molecular Design
Authors: Cheng Xue‐Feng , Shi Er‐Bo , Hou Xiang , Xia Shu‐Gang , He Jing‐Hui , Xu Qing‐Feng , Li Hua , Li Na‐Jun , Chen Dong‐Yun , Lu Jian‐Mei
Published: October 2016

Herein, two molecules based on urea and thiourea, which differ by only a single atom, were designed, successfully synthesized, and fabricated into resistive random‐access memory devices (RRAM). The urea‐based molecule showed binary write‐once‐read‐many (WORM) storage behavior, whereas the thiourea‐based molecule demonstrated ternary storage behavior. Atomic‐force microscopy (AFM) and X‐ray diffraction (XRD) patterns show that both molecules have smooth morphology and ordered layer‐by‐layer lamellar packing, which is beneficial for charge transportation and, consequently, device performance. Additionally, the optical and electrochemical properties indicate that the thiourea‐based molecule has a lower bandgap and may be polarized by trapped charges, thus the formation of a continuous conductive channel and electric switching occurs at lower bias voltage, which results in ternary WORM behavior. This study, together with our previous work on single‐atom substitution, may be useful to tune and improve device performance in the future design of organic memory.
Design of nanoscale enzyme complexes based on various scaffolding materials for biomass conversion and immobilization
Authors: Hyeon Jeong Eun , Shin Sang Kyu , Han Sung Ok
Published: October 2016

The utilization of scaffolds for enzyme immobilization involves advanced bionanotechnology applications in biorefinery fields, which can be achieved by optimizing the function of various enzymes. This review presents various current scaffolding techniques based on proteins, microbes and nanomaterials for enzyme immobilization, as well as the impact of these techniques on the biorefinery of lignocellulosic materials. Among them, architectural scaffolds have applied to useful strategies for protein engineering to improve the performance of immobilized enzymes in several industrial and research fields. In complexed enzyme systems that have critical roles in carbon metabolism, scaffolding proteins assemble different proteins in relatively durable configurations and facilitate collaborative protein interactions and functions. Additionally, a microbial strain, combined with designer enzyme complexes, can be applied to the immobilizing scaffold because the in vivo immobilizing technique has several benefits in enzymatic reaction systems related to both synthetic biology and metabolic engineering. Furthermore, with the advent of nanotechnology, nanomaterials possessing ideal physicochemical characteristics, such as mass transfer resistance, specific surface area and efficient enzyme loading, can be applied as novel and interesting scaffolds for enzyme immobilization. Intelligent application of various scaffolds to couple with nanoscale engineering tools and metabolic engineering technology may offer particular benefits in research.
Theoretical Calculations on the Feasibility of Microalgal Biofuels: Utilization of Marine Resources Could Help Realizing the Potential of Microalgae
Authors: Park Hanwool , Lee Choul‐Gyun
Published: October 2016

Microalgae have long been considered as one of most promising feedstocks with better characteristics for biofuels production over conventional energy crops. There have been a wide range of estimations on the feasibility of microalgal biofuels based on various productivity assumptions and data from different scales. The theoretical maximum algal biofuel productivity, however, can be calculated by the amount of solar irradiance and photosynthetic efficiency (PE), assuming other conditions are within the optimal range. Using the actual surface solar irradiance data around the world and PE of algal culture systems, maximum algal biomass and biofuel productivities were calculated, and feasibility of algal biofuel were assessed with the estimation. The results revealed that biofuel production would not easily meet the economic break‐even point and may not be sustainable at a large‐scale with the current algal biotechnology. Substantial reductions in the production cost, improvements in lipid productivity, recycling of resources, and utilization of non‐conventional resources will be necessary for feasible mass production of algal biofuel. Among the emerging technologies, cultivation of microalgae in the ocean shows great potentials to meet the resource requirements and economic feasibility in algal biofuel production by utilizing various marine resources.
Protease substrate profiling using bacterial display of self‐blocking affinity proteins and flow‐cytometric sorting
Authors: Sandersjöö Lisa , Jonsson Andreas , Löfblom John
Published: October 2016

Proteases are involved in fundamental biological processes and are important tools in both biotechnological and biomedical research. An important property of proteases is to discriminate among potential substrates. Here, a new method for substrate profiling of proteases is presented. The substrates are displayed between two anti‐idiotypic affinity domains on the Gram‐positive bacterium Staphylococcus carnosus. The first domain functions as a reporter tag and has affinity for a labeled reporter protein, whereas the second domain blocks the reporter tag from interacting with the reporter protein. Site‐specific proteolysis of the substrate results in release of the blocking domain, enabling the reporter tag to bind the labeled reporter protein. Proteolysis is therefore reflected in reporter binding, which is quantified by flow cytometry. First, the method with tobacco etch virus protease (TEVp) is evaluated and then the substrate preference of matrix metalloprotease‐1 (MMP‐1) is determined using two libraries of around three million substrates each. Identified substrate peptides contained the previously reported motif (PXXXHy) and on‐cell determination of apparent kcat/KM revealed that the enriched substrate peptides are hydrolyzed six to eight‐fold more efficiently than a previously reported substrate peptide. The method thus works as intended and the authors believe it has potential as an efficient tool for substrate profiling.
Overexpression of SRC‐3 promotes esophageal squamous cell carcinoma aggressiveness by enhancing cell growth and invasiveness
Authors: Xu Fang‐Ping , Liu Yan‐Hui , Luo Xin‐Lan , Zhang Fen , Zhou Hai‐Yu , Ge Yan , Liu Chao , Chen Jie , Luo Dong‐Lan , Yan Li‐Xu , Mei Ping , Xu Jie , Zhuang Heng‐Guo
Published: October 2016

Steroid receptor coactivator‐3 (SRC‐3), a transcriptional coactivator for nuclear receptors and other transcription factors, plays an important role in the genesis and progression of several cancers. However, studies investigated the role of SRC‐3 in esophageal squamous cell carcinomas (ESCCs) are limited, and the role of SRC‐3 in tumor progression remains unclear. We examined the expression of SRC‐3 in 8 ESCC cell lines and 302 human ESCC tissues by qPCR, Western blot, and immunohistochemistry. In addition, ESCC cell lines were subjected to proliferation and invasion assays, tumorigenicity assay, flow cytometry assay, qPCR, Western blot, and Chromatin Immunoprecipitation assay to investigate the role of SRC‐3 in cancer progression. SRC‐3 was overexpressed in 48% of cases and correlated with poor overall (P = 0.0076) and progression‐free (P = 0.0069) survival of surgically resected ESCC patient. Cox regression analysis revealed that SRC‐3 is an independent prognostic marker. Furthermore, we found that activation of insulin‐like growth factor (IGF)/AKT) was involved in the SRC‐3 on the cell growth and invasiveness in two ESCC cell lines, Eca109 and EC18 cells. SRC‐3 overexpression is clinically and functionally relevant to the progression of human ESCC, and might be a useful molecular target for ESCC prognosis and treatment.
A Fluorescent Probe for Neural Stem/Progenitor Cells with High Differentiation Capability into Neurons
Authors: Kim Beomsue , Feng Suihan , Yun Seong‐Wook , Leong Cheryl , Satapathy Rudrakanta , Wan Si Yan Diana , Chang Young‐Tae
Published: October 2016

Selection of a specific neural stem/progenitor cells (NSPCs) has attracted broad attention in regenerative medicine for neurological disorders. Here, we report a fluorescent probe, CDg13, and its application for isolating strong neurogenic NSPCs. In comparison to the NSPCs isolated by other biomarkers, CDg13‐stained NSPCs showed higher capability to differentiate into neurons. Target identification revealed that the fluorescence intensity of the probe within cells is inversely proportional to the expression levels of mouse and human Abcg2 transporters. These findings suggest that low Abcg2 expression is a biomarker for neurogenic NSPCs in mouse brain. Furthermore, CDg13 can be used to isolate Abcg2low cells from heterogeneous cell populations.
A Tandem Green–Red Heterodimeric Fluorescent Protein with High FRET Efficiency
Authors: Wiens Matthew D. , Shen Yi , Li Xi , Salem M. Alaraby , Smisdom Nick , Zhang Wei , Brown Alex , Campbell Robert E.
Published: October 2016

The tetrameric red fluorescent protein from Discosoma sp. coral (DsRed) has previously been engineered to produce dimeric and monomeric fluorescent variants with excitation and emission profiles that span the visible spectrum. The brightest of the effectively monomeric DsRed variants is tdTomato—a tandem fusion of a dimeric DsRed variant. Here we describe the engineering of brighter red (RRvT), green (GGvT), and green–red heterodimeric (GRvT) tdTomato variants. GRvT exhibited 99 % intramolecular FRET efficiency, resulting in long Stokes shift red fluorescence. These new variants could prove useful for multicolor live‐cell imaging applications.
Suicide in young children compared to young adolescents: Differences and commonalities
Authors: Knopf Alison
Published: October 2016

Children ages 5 to 11 who died by suicide were less likely to have shown signs of depression than children ages 12–14 who died by suicide, according to a new study. The younger children were more likely to have impulsivity as a precipitating factor, while the young adolescents were more likely to be depressed. Both groups had relationship problems, the younger children with family members or friends, and the adolescents with boyfriends or girlfriends. The rate of suicide among black children and adolescents has been increasing, while that among whites has been decreasing.
Palladium‐Catalyzed Direct Cross‐Coupling of Carboranyllithium with (Hetero)Aryl Halides
Authors: Lu Ju‐You , Wan Hong , Zhang Jianwei , Wang Zhixuan , Li Yang , Du Yongmei , Li Chunying , Liu Zhao‐Tie , Liu Zhong‐Wen , Lu Jian
Published: October 2016

A palladium‐catalyzed direct C‐arylation reaction of readily available cage carboranyllithium reagents with aryl halides has been developed for the first time. This method is applicable to a wide range of aryl halide substrates including aryl iodides, aryl bromides, and heteroaromatic halides.
Cytotoxicity of Exfoliated Layered Vanadium Dichalcogenides
Authors: Latiff Naziah Mohamad , Sofer Zdeněk , Fisher Adrian C. , Pumera Martin
Published: October 2016

Transition‐metal Group 5 vanadium dichalcogenides have shown promising properties for many applications, such as batteries, capacitors, electrocatalysts for hydrogen production and many more. However, their toxicological effects have not yet been well understood. Here, we studied the cytotoxicity of exfoliated VS2, VSe2 and VTe2 by incubating various concentrations of the materials with human lung carcinoma (A549) cells for 24 h and measuring the remaining cell viabilities after the treatment. We found that these vanadium dichalcogenides are relatively more toxic compared to Group 6 transition‐metal dichalcogenides (TMDs), namely MoS2, WS2 and WSe2. This study is important for a better understanding of the toxicity of TMDs in preparation for their actual commercialisation in the future.
Tribolumineszenz
Authors: Brandl Herbert , Täuscher Eric , Weiß Dieter
Published: October 2016

Der Beitrag gibt einen Überblick zum Thema Tribolumineszenz. Es wird die geschichtliche Entwicklung der Forschung dargestellt, gleichzeitig werden neuere Entdeckungen angesprochen sowie einige wissenschaftliche Grundlagen vermittelt. Ein umfangreicher experimenteller Teil soll dazu anregen, selber Experimente auf diesem wenig beachteten Gebiet der Chemie durchzuführen.
Assessment of reduced‐order unscented Kalman filter for parameter identification in 1‐dimensional blood flow models using experimental data
Authors: Caiazzo A. , Caforio Federica , Montecinos Gino , Muller Lucas O. , Blanco Pablo J. , Toro Eluterio F.
Published: October 2016

This work presents a detailed investigation of a parameter estimation approach on the basis of the reduced‐order unscented Kalman filter (ROUKF) in the context of 1‐dimensional blood flow models. In particular, the main aims of this study are (1) to investigate the effects of using real measurements versus synthetic data for the estimation procedure (i.e., numerical results of the same in silico model, perturbed with noise) and (2) to identify potential difficulties and limitations of the approach in clinically realistic applications to assess the applicability of the filter to such setups. For these purposes, the present numerical study is based on a recently published in vitro model of the arterial network, for which experimental flow and pressure measurements are available at few selected locations. To mimic clinically relevant situations, we focus on the estimation of terminal resistances and arterial wall parameters related to vessel mechanics (Young's modulus and wall thickness) using few experimental observations (at most a single pressure or flow measurement per vessel). In all cases, we first perform a theoretical identifiability analysis on the basis of the generalized sensitivity function, comparing then the results owith the ROUKF, using either synthetic or experimental data, to results obtained using reference parameters and to available measurements.
Automated femoral landmark extraction for optimal prosthesis placement in total hip arthroplasty
Authors: de Almeida Diogo F. , Ruben Rui B. , Folgado João , Fernandes Paulo R. , Gamelas João , Verhegghe Benedict , De Beule Matthieu
Published: October 2016

The automated extraction of anatomical reference landmarks in the femoral volume may improve speed, precision, and accuracy of surgical procedures, such as total hip arthroplasty. These landmarks are often hard to achieve, even via surgical incision. In addition, it provides a presurgical guidance for prosthesis sizing and placement. This study presents an automated workflow for femoral orientation and landmark extraction from a 3D surface mesh. The extraction of parameters such as the femoral neck axis, the femoral middle diaphysis axis, both trochanters and the center of the femoral head will allow the surgeon to establish the correct position of bony cuts to restore leg length and femoral offset. The definition of the medullary canal endosteal wall is used to position the prosthesis' stem. Furthermore, prosthesis alignment and sizing methods were implemented to provide the surgeon with presurgical information about performance of each of the patient‐specific femur‐implant couplings. The workflow considers different commercially available hip stems and has the potential to help the preoperative planning of a total hip arthroplasty in an accurate, repeatable, and reliable way. The positional and orientation errors are significantly reduced, and therefore, the risk of implant failure and subsequent revision surgery are also reduced.
Hepatic Vitamin A Content Investigation Using Coherent Anti‐Stokes Raman Scattering Microscopy
Authors: Legesse Fisseha Bekele , Heuke Sandro , Galler Kerstin , Hoffmann Patrick , Schmitt Michael , Neugebauer Ute , Bauer Michael , Popp Jürgen
Published: October 2016

Standard techniques for examining the distribution of vitamin A in liver either require staining or lead to rapid photobleaching of the molecule. A potentially better alternative approach is to use coherent anti‐Stokes Raman scattering (CARS) microscopy; a fast, label‐free, non‐disruptive imaging method that provides contrast based on molecular vibrations. This contribution evaluates the viability of CARS microscopy for imaging vitamin A within thick hepatic tissue under physiological conditions by tuning into its characteristic vibrational band in the fingerprint region. Additional information about the morphology and architecture of the tissue was acquired using second harmonic generation (SHG) and multi‐photon excited fluorescence (MPEF) to help mapping the intra‐lobular positions of the vitamin A droplets. We demonstrate the capability of our multimodal imaging framework to selectively image lipid‐soluble vitamin A droplets deep in bulk liver tissue with a high contrast while co‐registering a complementary morphological background that clearly visualizes hepatic lobules. The results obtained envisage the good prospect of the technique for in vivo studies assessing vitamin A distribution heterogeneity and how it is affected by the progression of hepatic diseases.