bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Chemistry of Poly(2‐oxazoline)s
Authors: Verbraeken Bart , Monnery Bryn D. , Lava Kathleen , Hoogenboom Richard 
Published: June 2018

AbstractResearch in the field of poly(2‐alkyl/aryl‐2‐oxazoline)s (PAOx) is rapidly expanding as this polymer class combines high synthetic versatility with good biocompatibility, opening up the way to highly functional (bio)materials. PAOx are prepared by living cationic ring‐opening polymerization (CROP) of 2‐oxazolines. The variety of 2‐oxazoline monomers that are readily available or can easily be synthesized allows for tuning of polymer properties and introduction of diverse functionalities.Moreover, thanks to the living nature of the CROP, well‐defined polymers with narrow molar mass distribution and high end‐group fidelity can be obtained. This article covers all aspects of PAOx ranging from the synthesis of 2‐oxazoline monomers, via an in‐depth discussion of the CROP mechanism to the synthesis and properties of functional PAOx (co)polymers. The presented research demonstrates that due to their structural adaptability and so‐called “stealth” behavior, PAOx are well‐suited for a range of biomedical applications, including polymer therapeutics, scaffolds for three‐dimensional cell culture, surface modification, matrix excipient for solid dispersions, and antimicrobial agents.The goal of this article is not to review all applications of PAOx, but to highlight key examples illustrating the numerous possibilities, broad application range and the general state‐of‐art use.
Protein Toxin Chaperoned by LRP‐1‐Targeted Virus‐Mimicking Vesicles Induces High‐Efficiency Glioblastoma Therapy In Vivo
Authors: Jiang Yu , Yang Weijing , Zhang Jian , Meng Fenghua , Zhong Zhiyuan 
Published: June 2018

AbstractGlioblastoma is a most intractable and high‐mortality malignancy because of its extremely low drug accessibility resulting from the blood–brain barrier (BBB). Here, it is reported that angiopep‐2‐directed and redox‐responsive virus‐mimicking polymersomes (ANG‐PS) (angiopep‐2 is a peptide targeting to low‐density lipoprotein receptor‐related protein‐1 (LRP‐1)) can efficiently and selectively chaperone saporin (SAP), a highly potent natural protein toxin, to orthotopic human glioblastoma xenografts in nude mice. Unlike chemotherapeutics, free SAP has a low cytotoxicity. SAP‐loaded ANG‐PS displays, however, a striking antitumor activity (half‐maximal inhibitory concentration, IC50 = 30.2 × 10−9m) toward U‐87 MG human glioblastoma cells in vitro as well as high BBB transcytosis and glioblastoma accumulation in vivo. The systemic administration of SAP‐loaded ANG‐PS to U‐87 MG orthotopic human‐glioblastoma‐bearing mice brings about little side effects, effective tumor inhibition, and significantly improved survival rate. The protein toxins chaperoned by LRP‐1‐targeted virus‐mimicking vesicles emerge as a novel and highly promising treatment modality for glioblastoma.
Black Arsenic: A Layered Semiconductor with Extreme In‐Plane Anisotropy
Authors: Chen Yabin , Chen Chaoyu , Kealhofer Robert , Liu Huili , Yuan Zhiquan , Jiang Lili , Suh Joonki , Park Joonsuk , Ko Changhyun , Choe Hwan Sung , Avila José , Zhong Mianzeng , Wei Zhongming , Li Jingbo , Li Shushen , Gao Hongjun , Liu Yunqi , Analytis James , Xia Qinglin , Asensio Maria C. , Wu Junqiao 
Published: June 2018

Abstract2D layered materials have emerged in recent years as a new platform to host novel electronic, optical, or excitonic physics and develop unprecedented nanoelectronic and energy applications. By definition, these materials are strongly anisotropic between the basal plane and cross the plane. The structural and property anisotropies inside their basal plane, however, are much less investigated. Black phosphorus, for example, is a 2D material that has such in‐plane anisotropy. Here, a rare chemical form of arsenic, called black‐arsenic (b‐As), is reported as a cousin of black phosphorus, as an extremely anisotropic layered semiconductor. Systematic characterization of the structural, electronic, thermal, and electrical properties of b‐As single crystals is performed, with particular focus on its anisotropies along two in‐plane principle axes, armchair (AC) and zigzag (ZZ). The analysis shows that b‐As exhibits higher or comparable electronic, thermal, and electric transport anisotropies between the AC and ZZ directions than any other known 2D crystals. Such extreme in‐plane anisotropies can potentially implement novel ideas for scientific research and device applications.
Increased Exciton Delocalization of Polymer upon Blending with Fullerene
Authors: Gautam Bhoj , Klump Erik , Yi Xueping , Constantinou Iordania , Shewmon Nathan , Salehi Amin , Lo Chi Kin , Zheng Zilong , Brédas Jean‐Luc , Gundogdu Kenan , Reynolds John R. , So Franky 
Published: June 2018

AbstractInterfaces between donor and acceptor in a polymer solar cell play a crucial role in exciton dissociation and charge photogeneration. While the importance of charge transfer (CT) excitons for free carrier generation is intensively studied, the effect of blending on the nature of the polymer excitons in relation to the blend nanomorphology remains largely unexplored. In this work, electroabsorption (EA) spectroscopy is used to study the excited‐state polarizability of polymer excitons in several polymer:fullerene blend systems, and it is found that excited‐state polarizability of polymer excitons in the blends is a strong function of blend nanomorphology. The increase in excited‐state polarizability with decreased domain size indicates that intermixing of states at the interface between the donor polymers and fullerene increases the exciton delocalization, resulting in an increase in exciton dissociation efficiency. This conclusion is further supported by transient absorption spectroscopy and time‐resolved photoluminescence measurements, along with the results from time‐dependent density functional theory calculations. These findings indicate that polymer excited‐state polarizability is a key parameter for efficient free carrier generation and should be considered in the design and development of high‐performance polymer solar cells.
Realization of In‐Plane p–n Junctions with Continuous Lattice of a Homogeneous Material
Authors: Huang Xiaochun , Liu Bing , Guan Jiaqi , Miao Guangyao , Lin Zijian , An Qichang , Zhu Xuetao , Wang Weihua , Guo Jiandong 
Published: June 2018

AbstractTwo‐dimensional (2D) in‐plane p–n junctions with a continuous interface have great potential in next‐generation devices. To date, the general fabrication strategies rely on lateral epitaxial growth of p‐ and n‐type 2D semiconductors. An in‐plane p–n junction is fabricated with homogeneous monolayer Te at the step edge on graphene/6H‐SiC(0001). Scanning tunneling spectroscopy reveals that Te on the terrace of trilayer graphene is p‐type, and it is n‐type on monolayer graphene. Atomic‐resolution images demonstrate the continuous lattice of the junction, and mappings of the electronic states visualize the type‐II band bending across the space‐charge region of 6.2 nm with a build‐in field of 4 × 105 V cm−1. The reported strategy can be extended to other 2D semiconductors on patternable substrates for designed fabrication of in‐plane junctions.
Rational Design of Ultrasensitive Pressure Sensors by Tailoring Microscopic Features
Authors: Peng Shuhua , Blanloeuil Philippe , Wu Shuying , Wang Chun H. 
Published: June 2018

AbstractWearable sensors are increasingly used in a wide range of applications such as tactile sensors and artificial skins for soft robotics, monitoring human motions for wellbeing and sports performance, and pressure control of compression garments for wound healing. In this work, an ultrasensitive resistive pressure sensor based on conductive polydimethylsiloxane (PDMS) thin films with different microstructures is presented. These microscopic features include micropyramids, micro‐semispheres, and micro‐semicylinders which are created by soft lithography replication of 3D printing templates. To enable piezoresistivity, a thin layer of carbon nanofibers (CNFs) is spray‐coated on the textured PDMS film. The resistance changes of the three microstructure designs under compression loading show that the micro‐semicylinder‐based sensor has the highest sensitivity of −3.6 kPa−1. Finite element modeling reveals that among the three designs, the micro‐semicylinders show the largest change in contact area under the same pressure, consistent with the experimental results that the largest resistance change under the same pressure. This sensor is capable of detecting pressure as low as 1.0 Pa. This 3D printing technology is a promising fabrication technique to design microstructured piezoresistive layers, paving the way to tailor sensor performance by engineering their microstructures and to produce ultrasensitive pressure sensors at low cost.
Robust Superhydrophobic Surface with Controlled Adhesion: In Situ Growth Depending on Its Bulk Phase Composition and Environment
Authors: Chen Kai , Hu Junyi , Wang Caoyu , Wu Mingpeng , Ding Cong , Gu Jiangjiang , Zhang Geng , Zheng Xinsheng , Cao Feifei 
Published: June 2018

AbstractIn nature, the superhydrophobic surfaces are almost in situ grown on its bulk phase under special environment. However, it is still a doubt how the bulk phase composition and external environment influence the structures and properties of in situ growth surfaces. To investigate the influence, a strategy is devised via using fluorine‐free benzoxazine as matrix model, selecting different metal chlorides to change the bulk phase composition of the matrix and utilizing different curing media to control the interface growth environment. It is found interestingly that the properties of in situ growth surfaces depend strongly on its bulk phase composition and external environment, and the superhydrophobic surface with controlled adhesion could be synthesized by in situ polymerization through one‐step curing and regulation of the bulk phase composition and growth environment. Moreover, the in situ growth superhydrophobic surface with controlled adhesion has high thermal stability, chemical stability, mechanical stability, and persistent stability. These findings not only show a unique idea for fabricating superhydrophobic surfaces with controlled adhesion, but also provide useful enlightenment for preparation and understanding of heterogeneous catalysts, sensors, and drag reducing materials.
Work Function Modification via Combined Charge‐Based Through‐Space Interaction and Surface Interaction
Authors: Yang Da Seul , Bilby David , Chung Kyeongwoon , Wenderott Jill K. , Jordahl Jacob , Kim Bo Hyun , Lahann Joerg , Green Peter F. , Kim Jinsang 
Published: June 2018

AbstractWork function modification of electrodes is an important factor to achieve high performance in organic electronics. However, a clear explanation of the origin of work function modification has remained elusive. Here, it is investigated how the work function of electrodes is affected by the charge‐based through‐space interaction with the well‐known surface interaction. The studies reveal that the formation of a surface dipole leads to a work function shift, even when the work function modifying layer and substrate are separated. A work function shift is also demonstrated by electrophoretic deposition of ionic polyelectrolytes while the same polyelectrolytes do not cause any work function shift when they are spin cast. More noteworthy is that a neutral (nonionic) polymer which has no specific surface‐interacting functional groups can induce work function shift of its substrate by a charge‐based through‐space interaction when deposited by electrospraying. These results provide a more comprehensive understanding of work function modification and motivate the design and selection of a wide range of effective work function modifying layers for organic electronics.
Direct Writing and Repairable Paper Flexible Electronics Using Nickel–Liquid Metal Ink
Authors: Chang Hao , Guo Rui , Sun Ziqiao , Wang Hongzhang , Hou Yi , Wang Qian , Rao Wei , Liu Jing 
Published: June 2018

AbstractLiquid metals such as gallium and its alloys can be printed on various substrates to form electronic circuits. However, up to now there are still few methods for the direct writing of liquid metals on common printed paper. Here, a novel conductive material prepared by adding metal powder to a gallium alloy is introduced. The proposed material exhibits low liquidity, excellent plasticity, significantly enhanced adhesivity to paper substrates, which guarantee the stable and flexible electrical connection. The oxide film wrapping the nickel powder forms a skeleton for additional oxidation products, resulting in superior adhesion to paper. In addition, several paper flexible electronic applications are showcased to demonstrate the practical value and reparability of this material. This work paves the way for the design of a facile method of preparing paper electronics.
Low‐Resistance Porous Nanocellular MnSe Electrodes for High‐Performance All‐Solid‐State Battery‐Supercapacitor Hybrid Devices
Authors: Tang Haichao , Yuan Yuliang , Meng Lu , Wang Weicheng , Lu Jianguo , Zeng Yujia , Huang Tieqi , Gao Chao 
Published: June 2018

AbstractSearching for materials with improved electrochemical behaviors is an important topic in portable energy storage devices. In this work a simple one‐step solvothermal process is developed to rationally synthesize nanocellular α‐MnSe and its applications in energy storage devices are studied. The MnSe faradic electrode shows a low internal resistance (0.37 Ω), high capacity (84.7 mAh g−1 at 10 mV s−1), good rate capability, and long cycle life. All‐solid‐state battery‐supercapacitor hybrid (BSH) devices are assembled using binder‐free nanocellular MnSe as the positive electrode and active carbon (AC) as the negative electrode. The MnSe//AC all‐solid‐state devices exhibit large energy and power densities (39.6 µWh cm−2 at 0.96 mW cm−2), extremely low internal resistance (only 1.34 Ω), fast charge process, outstanding cycle stability (119.79% retention after 8000 cycles), and flexibility with rather low bending loss. The wrist strap product by connecting three MnSe//AC all‐solid‐state devices in series can readily drive a green light‐emitting diode for 3 min after 5 s of charging process. This work demonstrates that MnSe is an ideal low‐resistance candidate of electrode materials for all‐solid‐state BSH devices, which is expected to facilitate the development in the portable and wearable energy storage.
A Combined Magnetic‐Acoustic Device for Simultaneous, Coaligned Application of Magnetic and Ultrasonic Fields
Authors: Barnsley Lester C. , Gray Michael D. , Beguin Estelle , Carugo Dario , Stride Eleanor 
Published: June 2018

AbstractAcoustically‐responsive microbubbles have been widely researched as agents for both diagnostic and therapeutic applications of ultrasound. There has also been considerable interest in magnetically‐functionalised microbubbles as multi‐modality imaging agents and carriers for targeted drug delivery. In this paper, we present a design for an integrated device capable of generating co‐aligned magnetic and acoustic fields in order to accumulate microbubbles at a specific location and to activate them acoustically. For this proof‐of‐concept study, the device was designed to concentrate microbubbles at a distance of 10 mm from the probe's surface, commensurate with relevant tissue depths in preclinical small animal models. Previous studies have indicated that both microbubble concentration and duration of cavitation activity are positively correlated with therapeutic effect. The utility of the device was assessed in vitro tests in a tissue‐mimicking phantom containing a single vessel (1.2 mm diameter). At a peak fluid velocity of 4.2 mm s−1 microbubble accumulation was observed under B‐mode ultrasound imaging and the corresponding cavitation activity was sustained for a period more than 4 times longer than that achieved with an identical acoustic field but in the absence of a magnet. The feasibility of developing a larger scale device for human applications is discussed.
Hydrophobic–hydrophilic cross‐linked matrices for controlled release formulation of Highly water‐soluble drug venlafaxine: Synthesis and evaluation studies
Authors: Asghar Saima , Minhas Muhammad Usman , Ahmad Mahmood , Khan Kifayat Ullah , Sohail Muhammad , Khalid Ikrima 
Published: June 2018

AbstractThis study was aimed to develop chemically cross‐linked matrix system of polycaprolactone‐co‐poly (methacrylic acid) through free radical polymerization method for controlled delivery of highly water‐soluble drug venlafaxine HCl. A hydrophobic polymer, polycaprolactone has been cross‐linked chemically with methacrylic acid by ethylene glycol dimethacrylate (EGDMA) as cross‐linking agent, and benzoyl peroxide was added as reaction initiator. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), and sol‐gel fraction were performed for characterization and structural analysis of polymeric system. Different feed ratios of polycaprolactone, methacrylic acid, and EGDMA were incorporated to investigate the effect of polymer, monomer, and degree of cross‐linking on swelling behavior and release pattern of model drug. pH‐responsive nature of hydrogel was evaluated at low and high pH. FTIR, TGA, and DSC confirmed the formation of new cross‐linked network. pH sensitivity of hydrogel is revealed by increased swelling at pH 7.4. Toxicity study was also performed on rabbits to evaluate cytotoxicity and biocompatibility of developed formulation. Polycaprolactone hydrogels showed low swelling with increased polymer and cross‐linker concentration while swelling increased with high concentration of monomer. Swelling controlled in vitro drug release was found in hydrogels. Gel contents were increased with increase in ratio of polymer, monomer, and cross‐linking agent. Toxicity study endorsed that developed hydrogels were nontoxic and biocompatible.
Piezoresistive E‐Skin Sensors Produced with Laser Engraved Molds
Authors: dos Santos Andreia , Pinela Nuno , Alves Pedro , Santos Rodrigo , Fortunato Elvira , Martins Rodrigo , Águas Hugo , Igreja Rui 
Published: June 2018

AbstractThe recent interest of electronic skin (e‐skin) has pushed the research toward the development of flexible sensors, namely, for pressure detection. Several mechanisms can be used to transduce pressure into electrical signals, but piezoresistivity presents advantages due to its simplicity. The microstructuration of the films composing these sensors is a common strategy to improve their sensitivity. As an alternative to conventional and expensive photolithography techniques and low customizable techniques based on natural molds, a novel strategy for the microstructuration of polydimethylsiloxane (PDMS) films is proposed, based on molds fabricated by laser engraving. After design optimization of these microstructured films, which relies on microcones, piezoresistive sensors with a limit of detection of 15 Pa and a sensitivity of −2.5 kPa−1 in the low‐pressure regime are obtained. These sensors are used with success on the detection of the blood pressure wave at the wrist, thus exhibiting a great potential for health applications.
Wanted dead or alive (probably dead): Stem group Polytrichaceae
Authors: Bippus Alexander C. , Escapa Ignacio E. , Tomescu Alexandru M. F. 
Published: June 2018

Premise of the StudyThe Polytrichaceae are a widespread and morphologically isolated moss lineage. Early attempts to characterize phylogenetic relationships within the family suggested that morphology is not phylogenetically informative. Two well‐characterized fossils similar to basal and derived Polytrichaceae (Meantoinea alophosioides and Eopolytrichum antiquum, respectively), are known from Cretaceous rocks. To assess the phylogenetic positions of these fossils and compare hypotheses of relationships recovered using molecular vs. morphological methods, we conducted a comprehensive morphology‐based phylogenetic study of Polytrichaceae.MethodsWe evaluated the phylogenetic relationships of Polytrichaceae using a data set of 100 morphological characters (including 11 continuously varying traits codified as continuous characters) scored for 44 species of acrocarpous mosses and parsimony as the optimality criterion.Key ResultsContinuous characters significantly increased the resolving power of the analyses. The overall ingroup topology was sensitive to rooting as determined by outgroup selection, with some analyses yielding results that were incongruent with those of molecular studies. Both fossils had stable phylogenetic relationships, irrespective of outgroup sampling.ConclusionsOur results suggest that morphology is useful in resolving phylogenetic relationships in the Polytrichaceae, if both discrete and continuous characters are used. However, our rooting experiments demonstrate that there is no superior way to root analyses and indicate that relationships within the family are best evaluated using unrooted networks without outgroup taxa. These rooting problems suggest that additional information is needed to understand the phylogenetic relationships of Polytrichaceae. Such additional information could come from fossils of stem group polytrichaceous mosses, which await discovery.
Copper‐Catalyzed Oxidative Cross‐Coupling/C−C Bond Cleavage/Cyclization of Aryl Methyl Ketones with 4‐Aminocoumarins: Domino Synthesis of Dicoumarin‐Fused [1,5]‐Diazocines
Authors: Peng Fei , Li Lili , Liu Jin , Chen Zhiwei 
Published: June 2018

AbstractA copper‐catalyzed domino process for the synthesis of dicoumarin‐fused [1,5]‐diazocines from aryl methyl ketones and 4‐aminocoumarins has been described, which is proposed to proceed via an unprecedented sequential oxidative cross‐coupling, C−C bond cleavage, and cyclization process. This method provides a versatile approach for the efficient synthesis of diazocines.
Catalyst and Sensitizer‐Free Visible‐Light‐Induced C(sp2)−H Chalcogenation of Arenes/ Heteroarenes with Dichalcogenides
Authors: Kumaraswamy Gullapalli , Ramesh Vankudoth , Gangadhar Maram , Vijaykumar Swargam 
Published: June 2018

AbstractA direct selenation of arenes and heteroarenes at room temperature has been accomplished. This protocol was enabled by a visible‐light‐promoted single‐electron‐transfer (SET) pathway without a directing group. An array of arenes and heteroarenes, such as indoles, pyrroles, and functionalized aryl substrates could go through this selenation with high yields and regioselectivity. The salient feature of this protocol is the SET achieved by irradiating one of two organic molecules thereby avoiding a sensitizer to form a radical ion pair.