bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhanced Electroluminescence from Organic Light‐Emitting Diodes with an Organic–Inorganic Perovskite Host Layer
Authors: Matsushima Toshinori , Qin Chuanjiang , Goushi Kenichi , Bencheikh Fatima , Komino Takeshi , Leyden Matthew , Sandanayaka Atula S. D. , Adachi Chihaya
Published: August 2018

The development of host materials with high performance is essential for fabrication of efficient and stable organic light‐emitting diodes (OLEDs). Although host materials used in OLEDs are typically organics, in this study, it is shown that the organic–inorganic perovskite CH3NH3PbCl3 (MAPbCl3) can be used as a host layer for OLEDs. Vacuum‐evaporated MAPbCl3 films have a wide band gap of about 3 eV and very high and relatively balanced hole and electron mobilities, which are suitable for the host material. Photoluminescence and electroluminescence take place through energy transfer from MAPbCl3 to an organic emitter in films. Incorporation of an MAPbCl3 host layer into OLEDs leads to a reduction of driving voltage and enhancement of external quantum efficiency as compared to devices with a conventional organic host layer. Additionally, OLEDs with an MAPbCl3 host layer demonstrate very good operational stability under continuous current operation. These results can be extensively applied to organic‐ and perovskite‐based optoelectronics.
De Novo Synthesis and Assembly of Flexible and Biocompatible Physical Sensing Platforms
Authors: Ye Chao , Wang Jianjin , Xu Yiyi , Zheng Ke , Wang Xiaoyin , Ling Shengjie , Kaplan David L.
Published: August 2018

Flexible physical sensing platforms (PSP) that can detect and communicate with surrounding physical data, such as force, strain, and temperature, are of interest in a variety of high‐tech fields, such as for wearable electronics, soft robotics, and real‐time healthcare monitoring. However, a crucial question remains relative to the design and assembly of PSPs that can meet the multitude of requirements for such devices, such as biocompatibility, stretchability, and high‐sensitivity to the target factor. In this study, a flexible PSP system based on graphene and biodegradable copolyester poly(CL‐co‐TOSUO) (PCT), which is synthesized by ring‐opening copolymerization of ε‐caprolactone (CL) and 1,4,8‐trioxaspiro‐[4,6]‐9‐undecanone (TOSUO). In this PSP system, graphene acts as conductive layer to connect the electrical signals, while the highly‐stretchable linear copolyester with structural transfer temperature (melting temperature of crystals) at 37 °C provides an active substrate to sense moderate mechanical and temperature stimuli. The resultant PCT/graphene PSP features high sensitivity for a manifold of mild surrounding physical stimuli, such as finger touch and movement, sound vibrations, body temperature, and light bulb temperature, showing promising applications in healthcare monitoring, human–machine interface, as well as soft robotics.
Thin Metallic Heat Sink for Interfacial Thermal Management in Biointegrated Optoelectronic Devices
Authors: Jung Han Hee , Song Juwon , Nie Shuang , Jung Han Na , Kim Min Seok , Jeong Jae‐Woong , Song Young Min , Song Jizhou , Jang Kyung‐In
Published: August 2018

The applications of modern optoelectronic devices have been extended, and they now provide practical means for seamless real‐time monitoring of blood flow dynamics, by being integrated with flexible and stretchable wearable sensor platform technology. However, thermal management of these devices remains limited by undesired thermal energy originating from the heating of the light‐emitting diode. Specifically, the surface temperature of the optoelectronic device becomes very high compared to that of the adjacent biological tissue, causing challenges in skin–optoelectronics integration and functional deterioration of the light source. In this study, an optoelectronic module that integrates the light‐emitting diode, photodetector, and a thin metallic heat sink element for sustainable in situ thermal management is developed. Experimental and computational analysis results indicate that the proposed optoelectronic device has excellent heat dissipation capabilities for thermally safe long‐term usability, due to the high thermal conductivity of the device and film‐type geometrical design of the embedded heat sink for skin application. The proposed optoelectronic device architecture with metallic heat sink offers an ideal option for blood flow monitoring by providing both mechanical and thermal compatibility with biological tissue suitable for long‐term clinical applications.
Toward Electrically Pumped Polymer Lasing: Light‐Emitting Diodes Based on Microcavity Arrays of Distributed Bragg Gratings
Authors: Huang Cuiying , Zhang Xinping , Wang Jisheng , Hong Cuiyue
Published: August 2018

Electrically pumped organic lasers have been a challenge for years. The most crucial problem is that the density of charge carriers is much lower than the threshold required for lasing as compared with optical pumping. Apparently, increasing the density of charge carriers and reducing the threshold are two practical routes for solving the problem. Reducing the pump threshold depends strongly on the structural design and the operation‐mode control in the device. Here, a large‐area array of microcavities is employed to construct the light‐emitting diodes (LEDs) using distributed Bragg gratings (DBGs) as high‐efficiency reflectors and the homogeneous poly[(9,9‐dioctylfluorenyl‐2,7‐diyl)‐alt‐co‐(1,4‐benzo‐(2,1′,3)‐thiadiazole)] films in‐between as the active cavity body. Simultaneous lasing of multiple longitudinal modes at optical pumping verifies the optical feedback and oscillation mechanisms in such DBG‐based microcavities. Further successful construction of light‐emitting diodes using these microcavity arrays and the observation of narrowing of the electroluminescence spectrum due to the selectivity by the microcavities and the increase of the excitation electrical field suggest that the LED design here defines a promising step toward electrically pumped polymer lasers.
Extremely Efficient Transparent Flexible Organic Light‐Emitting Diodes with Nanostructured Composite Electrodes
Authors: Xiang Heng‐Yang , Li Yan‐Qing , Meng Shuai‐Shuai , Lee Chun‐Sing , Chen Lin‐Sen , Tang Jian‐Xin
Published: August 2018

Transparent flexible organic light‐emitting diodes (TF‐OLEDs) are emerging as a leading technique in bendable display and curved lighting applications due to their merits including superior mechanical flexibility, low power consumption, and broad color gamut. However, it is challenging to turn TF‐OLEDs into a power‐efficient large‐area light source. Here, an improved TF‐OLED structure on a plastic substrate that achieves a device transparency over 70% and extremely efficient warm‐white emission from both sides is reported. The key feature of this device structure is the combination of transparent metal–dielectric composite electrodes, which are patterned with moth‐eye nanostructures for broadband and angle‐independent light outcoupling. By collectively reducing ohmic losses and releasing the trapped photons, the TF‐OLEDs achieve a record external quantum efficiency of 72.4% and power efficiency of 168.5 lm W−1 with a color‐rendering index over 84. These results present the great potential of TF‐OLEDs for use in a wide variety of flexible applications.
Transition Metal Doped Smart Glass with Pressure and Temperature Sensitive Luminescence
Authors: Lv Shichao , Shanmugavelu B. , Wang Yunpeng , Mao Qiannan , Zhao Yujun , Yu Yongze , Hao Jianhua , Zhang Qinyuan , Qiu Jianrong , Zhou Shifeng
Published: August 2018

The development of future transparent intelligent systems demands smart glass with multifunctional sensing capabilities. Here, the realization of a smart glass with dual temperature and pressure sensing function by using Mn2+‐doped nanostructured gallate glass for the first time is reported. The material exhibits exceptional temperature response in the range of 323–523 K and the maximal relative temperature sensitivity reaches as high as 2.51% K−1 at 523 K. The material is also sensitive to the pressure fluctuation and displays bright green pressure‐induced luminescence. A combination of structural and optical analysis and theoretical calculation reveals that the local dopant orientation in nanodomain inside glass contributes to the previously unrealized sensing behavior. The critical factors governing the sensing performance are identified and the cooperative effects between the local chemical bonding and domain size contribute greatly to the remarkable enhancement of the sensitivity. The results highlight that the precise control over the doping process offers a great opportunity to design new smart glass.
Bioinspired Deamination of α‐Amino Acid Derivatives Catalyzed by a Palladium/Nickel Complex
Authors: Deng Gongtao , Chen Jie , Sun Wangbin , Bian Kehan , Jiang Yaojia , Loh Teck‐Peng
Published: August 2018

An efficient bioinspired deamination method of both natural and unnatural amino acid derivatives has been developed. This method provides easy access to a wide variety of useful α, β‐unsaturated carbonyl compounds. The reaction is realized with two transition metal catalysts (palladium and Nickel) in‐easy handling procedure. A possible reaction pathway is also proposed and the control experiments support the involvement of the palladium‐catalyzed inert sp3 C−H activation as one of the key steps.

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Molecular Simulation Studies of Cyanine‐Based Chromonic Mesogens: Spontaneous Symmetry Breaking to Form Chiral Aggregates and the Formation of a Novel Lamellar Structure
Authors: Thind Romnik , Walker Martin , Wilson Mark R.
Published: August 2018

All‐atom molecular dynamics simulations are performed on two chromonic mesogens in aqueous solution: 5,5′‐dimethoxy‐bis‐(3,3′‐di‐sulphopropyl)‐thiacyanine triethylammonium salt (Dye A) and 5,5′‐dichloro‐bis‐(3,3′‐di‐sulphopropyl)‐thiacyanine triethylammonuim salt (Dye B). Simulations demonstrate the formation of self‐assembled chromonic aggregates with an interlayer distance of ≈0.35 nm, with neighboring molecules showing a predominantly head‐to‐tail antiparallel stacking arrangement to minimize electrostatic repulsion between hydrophilic groups. Strong overlap of the aromatic rings occurs within the self‐assembled columns, characteristic of H‐aggregation in aqueous solution. At low concentrations, aggregates of Dye A form chiral columns, despite the presence of strictly achiral species. Chirality arises out of the minimization of steric repulsion between methoxy groups, which would otherwise disrupt the stacking of aromatic molecular cores. At higher concentrations, simulations suggest the interaction of short columns leads to the formation of an achiral‐layered structure in which hydrophobic aromatic regions of the molecule are sandwiched between two layers of hydrophilic groups. This novel lamellar structure is suggested as a likely candidate for the structure of a J‐aggregate. The latter is known to exhibit intense red‐shifted absorption peaks in solution but their structure has not yet been characterized. Self‐organization of such structures provides a route to the formation of “smectic” chromonic mesophases.
Synthesis and characterization of bis(oxiranylmethyl)sulfanes as new epoxide‐terminated polysulfide prepolymers and their use in synthesis of new amine‐cured polysulfide polymers
Authors: Pirayesh Amin , Salami‐Kalajahi Mehdi , Roghani‐Mamaqani Hossein , Mazloomi‐Rezvani Mahsa
Published: August 2018

The main disadvantages of polysulfide polymers are their complicated curing systems and their low solubility in different solvents. To overcome these problems, bis(oxiranylmethyl)sulfanes as new epoxide‐terminated polysulfide prepolymers were synthesized and their amine‐cured polymers were examined by different analysis methods. 1H NMR, 13C NMR, and FT‐IR have been used to characterize structure of the synthesized prepolymers and polymers and sulfur content of all samples has been investigated by CHNS elemental analysis. X‐ray diffraction analysis showed that all samples were semi‐crystalline and differential scanning calorimetry was used to study thermal transitions of prepolymers and polymers. As an advantage, all prepolymers and linear polymers were dissolved in sulfur‐ and nitrogen‐containing solvents. Synthesized polymers had low thermal stability with one‐step degradation process and they were in rubbery state with Tg values lower than 0°C. Conclusively, thermophysical properties of polymers depended on utilized prepolymer and amine‐containing compounds as precursors.
Pioneering Use of Ionic Liquid‐Based Aqueous Biphasic Systems as Membrane‐Free Batteries
Authors: Navalpotro Paula , Neves Catarina M. S. S. , Palma Jesus , Freire Mara G. , Coutinho João A. P. , Marcilla Rebeca
Published: August 2018

Aqueous biphasic systems (ABS) formed by water, ionic liquids (ILs), and salts, in which the two phases are water rich, are demonstrated here to act as potential membrane‐free batteries. This concept is feasible due to the selective enrichment of redox organic molecules in each aqueous phase of ABS, which spontaneously form two liquid‐phases above given concentrations of salt and IL. Therefore, the required separation of electrolytes in the battery is not driven by an expensive membrane that hampers mass transfer, but instead, by the intrinsic immiscibility of the two liquid phases. Moreover, the crosscontamination typically occurring through the ineffective membranes is determined by the partition coefficients of the active molecules between the two phases. The phase diagrams of a series of IL‐based ABS are characterized, the partition coefficients of several redox organic molecules are determined, and the electrochemistry of these redox‐active immiscible phases is evaluated, allowing appraisal of the battery performance. Several redox ABS that may be used in total aqueous membrane‐free batteries with theoretical battery voltages as high as 1.6 V are identified. The viability of a membrane‐free battery composed of an IL‐based ABS containing methyl viologen and 2,2,6,6‐tetramethyl‐1‐piperidinyloxy as active species is demonstrated.
Pre‐Oxidation‐Tuned Microstructures of Carbon Anodes Derived from Pitch for Enhancing Na Storage Performance
Authors: Lu Yaxiang , Zhao Chenglong , Qi Xingguo , Qi Yuruo , Li Hong , Huang Xuejie , Chen Liquan , Hu Yong‐Sheng
Published: August 2018

Disordered carbons have captured extensive interest as anode materials for Na‐ion batteries (NIBs) due to the abundant resources, competitive specific capacity, and low cost. Here, a facile strategy of pre‐oxidation is successfully adopted to tune the microstructure of carbon anode to facilitate sodium storage. Pitch is selected as the low‐cost and high carbon yield precursor. An easy pre‐oxidation treatment in air can enable pitch to realize an effective structural conversion from ordered to disordered at further carbonization processes. Compared with the carbonized pristine pitch, the carbonized pre‐oxidation pitch increases the carbon yield from 54 to 67%, the sodium storage capacity from 94.0 to 300.6 mAh g−1, and the initial Coulombic efficiency from 64.2 to 88.6%. Experiment results reveal that the introduction of oxygen based functional groups is the key to achieve the highly disordered structure, not only ensuring the cross‐linkage during low‐temperature pre‐oxidation process but also suppressing the carbon structure from melting and rearranging in the high‐temperature carbonization process. Most importantly, this facile pre‐oxidation strategy can also be extended to other carbon precursors to facilitate the low‐cost and high‐performance disordered carbon anodes for NIBs and beyond.
Mechanistic Insights of Zn2+ Storage in Sodium Vanadates
Authors: Guo Xun , Fang Guozhao , Zhang Wenyu , Zhou Jiang , Shan Lutong , Wang Liangbing , Wang Chao , Lin Tianquan , Tang Yan , Liang Shuquan
Published: August 2018

Rechargeable aqueous zinc‐ion batteries (ZIBs) with high safety and low‐cost are highly desirable for grid‐scale energy storage, yet the energy storage mechanisms in the current cathode materials are still complicated and unclear. Hence, several sodium vanadates with NaV3O8‐type layered structure (e.g., Na5V12O32 and HNaV6O16·4H2O) and β‐Na0.33V2O5‐type tunneled structure (e.g., Na0.76V6O15) are constructed and the storage/release behaviors of Zn2+ ions are deeply investigated in these two typical structures. It should be mentioned that the 2D layered Na5V12O32 and HNaV6O16·4H2O with more effective path for Zn2+ diffusion exhibit higher ion diffusion coefficients than that of tunneled Na0.76V6O15. As a result, Na5V12O32 delivers higher capacity than that of Na0.76V6O15, and a long‐term cyclic performance up to 2000 cycles at 4.0 A g−1 in spite of its capacity fading. This work provides a new perspective of Zn2+ storage mechanism in aqueous ZIB systems.
High‐Capacity All‐Solid‐State Sodium Metal Battery with Hybrid Polymer Electrolytes
Authors: Zheng Yongwei , Pan Qiwei , Clites Mallory , Byles Bryan W. , Pomerantseva Ekaterina , Li Christopher Y.
Published: August 2018

All‐solid‐state sodium metal batteries (SSMBs) are of great interest for their high theoretical capacity, nonflammability, and relatively low cost owing partially to the abundance of sodium recourses. However, it is challenging to fabricate SSMBs because compared with their counterparts, which contain lithium metal, sodium metal is mechanically softer and more reactive toward the electrolyte. Herein, the synthesis and electrochemical properties of newly designed sodium‐containing hybrid network solid polymer electrolytes (SPEs) and their application in SSMBs are reported. The hybrid network is synthesized by controlled crosslinking of octakis(3‐glycidyloxypropyldimethylsiloxy)octasilsesquioxane and amine‐terminated polyethylene glycol in existence with sodium perchlorate (NaClO4). Plating and stripping experiments using symmetric cells show prolonged cycle life of the SPEs, >5150 and 3550 h at current density of 0.1 and 0.5 mA cm−2, respectively. The results for the first time show that the SPE|sodium metal interface migrates into the SPE phase upon cycling. SSMBs fabricated with the hybrid SPE sandwiched between sodium metal anode and bilayered δ‐NaxV2O5 cathode exhibit record‐high specific capacity for solid sodium‐ion batteries of 305 mAh g−1 and excellent Coulombic efficiency. This work demonstrates that the hybrid network SPEs are promising for SSMB applications.
Surface remobilization of buoyancy‐driven surfactant‐laden drops at low reynolds and capillary numbers
Authors: White Andrew R. , Ward Thomas
Published: August 2018

It is well known that the terminal velocity of a drop settling in a viscous fluid is impacted by surface tension gradients. These gradients can develop because of nonuniform accumulation of surfactant on the surface as a result of a number of transport mechanisms. Here, a surfactant transport model based on a sorption‐limited Frumkin framework is used to describe surfactant transport in the presence of both surface convection and diffusion at low Reynolds and capillary numbers. Constants characterizing surfactant transport in the Frumkin framework are experimentally determined and used to predict aqueous drop velocities with varying surfactant concentrations and volumes. Computation is carried out by satisfying equations governing mass, momentum, and interface species conservation. Experiments demonstrate qualitative and quantitative agreement between predicted and measured drop velocities. It is shown that surface remobilization explains some observed trends in measured velocity as the drop size decreases. © 2018 American Institute of Chemical Engineers AIChE J, 65: 294–304, 2019
Highly multiplexed proteomic analysis reveals significant tissue and exosomal coagulation pathway derangement in chronic rhinosinusitis with nasal polyps
Authors: Mueller Sarina K. , Nocera Angela L. , Dillon Simon T. , Wu Dawei , Libermann Towia A. , Bleier Benjamin S.
Published: August 2018

Background

The coagulation pathway has been previously implicated in the etiopathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) through analysis of individual proteins within the cascade. The purpose of this study was to: (1) apply a large‐scale proteomic approach to confirm these previous findings; and (2) correlate the protein aberrations between tissue and exosomes to establish exosomal proteomics as a method to probe the pathophysiology of CRSwNP.

Methods

This investigation was an internal review board–approved study in which matched tissue and mucus exosomal proteomes were compared between control and CRSwNP (n = 10/group) using an aptamer‐based proteomic array and confirmed using whole transcriptome sequencing. Protein expression and the correlation between samples were calculated using Student's t‐test and Benjamini‐Hochberg procedures followed by the application of Ingenuity Pathway and MetaCore™ bioinformatics analyses.

Results

Among all protein pathways, the coagulation cascade was the most significantly associated with CRSwNP (p = 2.85e‐8). Among the 13 significantly altered coagulation‐related tissue proteins, fibronectin and fibrinogen gamma chains were the most overexpressed in CRSwNP relative to control (fold change [FC], 2.59; p = 0.006; and FC, 2.38; p < 0.001, respectively), whereas von Willebrand factor was the most underexpressed (FC, −3.06; p < 0.001). The exosomal fibrinolysis and coagulation pathway proteomes exhibited strong inverse and significant correlations with the tissue findings (r = −0.86; p = 0.013; and r = −0.79; p = 0.007, respectively).

Conclusion

Our proteomic analysis confirmed that the coagulation pathway is highly significantly deranged within nasal polyp tissue. The correlation between tissue‐ and mucus‐derived exosomal fibrinolysis and coagulation protein alterations were strong, inverse, and highly significant. This lends further support to the emerging concept of exosomal proteomic analysis as a method to study chronic sinonasal inflammation.
High tissue eosinophilia as a marker to predict recurrence for eosinophilic chronic rhinosinusitis: a systematic review and meta‐analysis
Authors: McHugh Tobial , Snidvongs Kornkiat , Xie Michael , Banglawala Sarfaraz , Sommer Doron
Published: August 2018

Background

Patients with eosinophilic chronic rhinosinusitis (ECRS) have been shown to have greater disease severity and poorer treatment outcomes after sinus surgery. Although the inflammatory pattern of ECRS is essential to diagnosing this subtype, there is currently no consensus for diagnosis. Our aim in this study was to determine whether high tissue eosinophilia (HTE), measured as eosinophils per high‐power field (eos/HPF), could be used to define ECRS based on likelihood of recurrence.

Methods

Embase, Medline, and PubMed databases were searched for studies that reported HTE and recurrence in ECRS patients after surgical treatment. We used a random‐effects bivariate meta‐analysis to calculate summary sensitivity, specificity, and diagnostic odds ratios (DORs) for detecting ECRS at different HTE cut‐off scores using risk of recurrence as the primary outcome.

Results

We identified 11 articles (n = 3183) that reported HTE associated with recurrence. A cut‐off value of >55 eos/HPF showed the highest sensitivity (0.87; 95% confidence interval [CI], 0.82‐0.91), specificity (0.97; 95% CI, 0.93‐0.99), and DOR (232.7; 95% CI, 91.0‐595.1). Meta‐regression analysis performed showed that the Quality Assessment of Diagnostic Accuracy Studies score (p = 0.1287), geographic location (p = 0.3745), follow‐up time (p = 0.2879), and study design (p = 0.1865) did not affect the test accuracy.

Conclusion

Our findings suggest that using eos/HPF has good diagnostic accuracy and may be a useful tool for identifying ECRS patients. Based on the results of our meta‐analysis, we recommend a cut‐off value of >55 eos/HPF for predicting the likelihood of recurrence of ECRS.
Spiroverknüpfte und ringanellierte 1,2,4‐Trioxepan‐, 1,2,4‐Trioxocan‐ und 1,2,4‐Trioxonan‐Cyclohexadienone: cyclische Peroxide mit ungewöhnlicher Ringkonformationsdynamik
Authors: Eske Angelika , Ecker Sabrina , Fendinger Carolina , Goldfuss Bernd , Jonen Matthis , Lefarth Jens , Neudörfl Jörg‐M. , Spilles Matthias , Griesbeck Axel G.
Published: August 2018

C‐3‐ oder C‐4‐hydroxyalkylierte Phenole sind hochreaktive Substrate für die Hydroperoxierung durch Oxone® und führen zur Bildung von tertiären C‐4‐Hydroperoxiden. Diese Reaktion kann auch mit photochemisch erzeugtem Singulett‐Sauerstoff durchgeführt werden. Andere charakteristische Singulett‐Sauerstoffreaktionen verlaufen jedoch nicht mit Caroat. Die zunächst gebildeten Hydroperoxide werden unter Lewis‐Säure‐Katalyse mit Bor‐, Indium‐ oder Eisen‐basierten Katalysatoren zu spiroverknüpften Peroxiden 6, 9 cyclisiert, die eine eingeschränkte Ringinversion aufweisen, während die größeren neungliedrigen Peroxide 12 thermisch weniger stabil sind und – möglicherweise korreliert – auch eine höhere Ringflexibilität aufweisen (durch NMR‐Analyse).
Enantioselective Construction of Tertiary Boronic Esters by Conjunctive Cross‐Coupling
Authors: Myhill Jesse A. , Zhang Liang , Lovinger Gabriel J. , Morken James P.
Published: August 2018

Catalytic enantioselective conjunctive cross‐coupling has been developed to construct tertiary alkylboronic esters. These reactions occur with good yield and enantioselectivity for a range of substrates. Mechanistic experiments reveal aspects of the catalytic cycle that allow hindered substrates to react without significant complicating side reactions.
Modular Functionalization of Arenes in a Triply Selective Sequence: Rapid C(sp2) and C(sp3) Coupling of C−Br, C−OTf, and C−Cl Bonds Enabled by a Single Palladium(I) Dimer
Authors: Keaveney Sinead T. , Kundu Gourab , Schoenebeck Franziska
Published: August 2018

Full control over multiple competing coupling sites would enable straightforward access to densely functionalized compound libraries. Historically, the site selection in Pd0‐catalyzed functionalizations of poly(pseudo)halogenated arenes has been unpredictable, being dependent on the employed catalyst, the reaction conditions, and the substrate itself. Building on our previous report of C−Br‐selective functionalization in the presence of C−OTf and C−Cl bonds, we herein complete the sequence and demonstrate the first general arylations and alkylations of C−OTf bonds (in <10 min), followed by functionalization of the C−Cl site (in <25 min), at room temperature using the same air‐ and moisture‐stable PdI dimer. This allowed the realization of the first general and triply selective sequential C−C coupling (in 2D and 3D space) of C−Br followed by C−OTf and then C−Cl bonds.
A Homoleptic KrF2 Complex, [Hg(KrF2)8][AsF6]2⋅2 HF
Authors: De Backere John R. , Schrobilgen Gary J.
Published: August 2018

The reaction of Hg(AsF6)2 with a large molar excess of KrF2 in anhydrous HF has afforded the first homoleptic KrF2 coordination complex of a metal cation, [Hg(KrF2)8][AsF6]2⋅2 HF. The [Hg(KrF2)8]2+ dication is well‐isolated in the low‐temperature crystal structure of its HF‐solvated [AsF6]− salt, and consists of eight KrF2 molecules that are terminally coordinated to Hg2+ by means of Hg−F(KrF) bonds to form a slightly distorted, square‐antiprismatic coordination sphere around mercury. The Raman spectrum of [Hg(KrF2)8]2+ was assigned with the aid of calculated gas‐phase vibrational frequencies. Computational studies indicate that both electrostatic and orbital interactions are important for metal–ligand bonding and provide insight into the geometry of the [Hg(KrF2)8]2+ cation and the nature of noble‐gas difluoride ligand bonding.
Moving beyond fitting fish into equations: Progressing the fish passage debate in the Anthropocene
Authors: Birnie‐Gauvin Kim , Franklin Paul , Wilkes Martin , Aarestrup Kim
Published: August 2018

Realization of the importance of fish passage for migratory species has led to the development of innovative and creative solutions (‘fishways’) to mitigate the effects of artificial barriers in freshwater systems in the last few decades.

In many instances, however, the first move has been to attempt to engineer a solution to the problem, thus attempting to ‘fit fish into an equation’. These fishways are often derived from designs targeting salmonids in the Northern Hemisphere. They are rarely adequate, even for these strong‐swimming fish, and certainly appear to be unsuitable for most other species, not least for those of tropical regions.

Fishway design criteria do not adequately account for natural variation among individuals, populations and species. Moreover, engineered solutions cannot reinstate the natural habitat and geomorphological properties of the river, objectives that have been largely ignored.

This article discusses the most prominent issues with the current management and conservation of freshwater ecosystems as it pertains to fish passage. It is not intended as a review on fish passage, but rather a perspective on the issues related to fishways, as seen by practitioners.
User‐Centered evaluation of metadata schema for nonmovable cultural heritage: Murals and stone cave temples
Authors: Hu Xiao , Ng Jeremy , Xia Shengping
Published: August 2018

Digitization provides a solution for documentation and preservation of nonmovable cultural heritages. Despite efforts for the preservation of cultural heritages around the world, no well‐accepted metadata schema has been developed for murals and stone cave temples, which are often high‐value heritages built in ancient times. In addition, the literature is scarce on the user‐centered evaluation of metadata schemas of this kind. This study therefore aims to offer insights on developing and evaluating a metadata schema for organizing information of these historic and complex cultural heritages. In‐depth interviews were conducted with a total of 30 users, including 18 professional and 12 public users, and interview transcripts were coded through a qualitative content analysis approach. Findings reveal the importance of specific metadata elements as perceived by the two groups of end users, which correlated with their cultural heritage information‐seeking behaviors. In addition, the issues of standardization of cataloging of cultural heritage information and interoperability among metadata schemas have been raised by users for enhancing the user experience with digital platforms of cultural heritage information. The coding schema developed in this study can serve as a framework for follow‐up evaluations of metadata schemas, contributing to the ongoing development of cultural heritage metadata.
PSI: A probabilistic semantic interpretable framework for fine‐grained image ranking
Authors: Li Hanhui , Wu Hefeng , Li Donghui , Lin Shujin , Su Zhuo , Luo Xiaonan
Published: August 2018

Image Ranking is one of the key problems in information science research area. However, most current methods focus on increasing the performance, leaving the semantic gap problem, which refers to the learned ranking models are hard to be understood, remaining intact. Therefore, in this article, we aim at learning an interpretable ranking model to tackle the semantic gap in fine‐grained image ranking. We propose to combine attribute‐based representation and online passive‐aggressive (PA) learning based ranking models to achieve this goal. Besides, considering the highly localized instances in fine‐grained image ranking, we introduce a supervised constrained clustering method to gather class‐balanced training instances for local PA‐based models, and incorporate the learned local models into a unified probabilistic framework. Extensive experiments on the benchmark demonstrate that the proposed framework outperforms state‐of‐the‐art methods in terms of accuracy and speed.
Control for Time‐Varying Delay Systems by Integrating Semi‐Discretization and Hysteresis‐Based Switching
Authors: Shao Chenhui , Li Shuang , Li Haitao , Sheng Jie
Published: August 2018

In this paper, we develop an innovative control method for linear systems with time‐varying delay by integrating the semi‐discretization method and the hysteresis‐based switching algorithm. The semi‐discretization method is adopted to design an optimal controller for each fixed time‐delay and form a candidate controller family. The switching algorithm acts as the principal law for switching among various controllers according to the instantaneous value of the time‐delay. A theoretical proof is presented regarding the stability of the switching time‐delay system. It is shown that the most significant factors that affect the system stability are the size of the candidate controller family, the value of the switching coefficient, and the changing rate of the time‐delay. Two case studies are presented to show the effectiveness of the proposed method.
A Sensitivity‐Based Construction Approach to Variance Minimization of Markov Decision Processes
Authors: Huang Yonghao , Chen Xi
Published: August 2018

With a long‐run average performance as the primary criterion for a Markov decision process, variance measures are studied as its secondary criteria. The steady‐state variance and the limiting average variance along a sample path are discussed. The latter one is difficult to handle due to its special form. With a sensitivity‐based approach, the difference formula for the sample‐path variance under different policies is intuitively constructed and then the optimality equation is presented. Moreover a policy iteration algorithm is developed. This work extends the sensitivity‐based construction approach to Markov decision processes with non‐standard performance criteria. The difference between these two types of variance and bias criteria is illustrated with a numerical example.
Finite‐Time Stabilization of Coupled Systems on Networks with Time‐Varying Delays via Periodically Intermittent Control
Authors: Wu Yongbao , Liu Yuntao , Li Wenxue
Published: August 2018

In this paper, finite‐time stabilization of coupled systems on networks with time‐varying delays (CSNTDs) via periodically intermittent control is studied. Both delayed subsystems and delayed couplings are considered; the self‐delays of different subsystems in delayed couplings are not identical. A periodically intermittent controller is designed to stabilize CSNTDs within finite time, and the stabilization duration is closely related to the topological structures of networks. Furthermore, two sufficient criteria are developed to ensure CSNTDs under periodically intermittent control can be stabilized within finite time by using an approach that combines the Lyapunov method with Kirchhoff's Matrix Tree Theorem. Then finite‐time stabilization of coupled oscillators with time‐varying delays is given as a practical application and sufficient criteria is obtained. Finally, a numerical simulation is proposed to support our results and show the effectiveness of the controller.
Finite‐Time Stability of Linear Caputo‐Katugampola Fractional‐Order Time Delay Systems
Authors: Ben Makhlouf Abdellatif , Nagy A. M.
Published: August 2018

In this paper, a finite‐time stability procedure is suggested for a class of Caputo‐Katugampola fractional‐order time delay systems. Sufficient conditions are derived to prove this fact. Numerical results are provided to demonstrate the validity of our theoretical results.
Two colorimetric fluorescent turn‐on chemosensors for detection of Al3+and N3−: Synthesis, photophysical and computational studies
Authors: Abebe Fasil , Sutton Treshaun , Perkins Pierce , Shaw Roosevelt
Published: August 2018

Two new rhodamine derivative L1 and L2 bearing 2‐methoxy‐1‐naphthaldehyde and 5‐bromo‐3‐methoxy salicylaldehyde units were designed and synthesized using microwave‐assisted organic synthesis and utilized towards sequential fluorescence detection of aluminum ion (Al3+) and azide (N3−) in aqueous acetonitrile solution. Aluminum ion (Al3+) triggers the formation of highly fluorescent ring‐open spirolactam. The fluorescence and colorimetric response of the L1‐Al3+ and L2‐Al3+ complexes were quenched by the addition of N3−, which extracting the Al3+ from the complexes and turn‐off the sensors, confirming that the recognition process is reversible. The recognition ability of the sensors was investigated by fluorescence titration, Job's plot, 1H‐NMR spectroscopy and density functional theory (DFT) calculations.
MyMOOCSpace: Mobile cloud‐based system tool to improve collaboration and preparation of group assessments in traditional engineering courses in higher education
Authors: Ramírez‐Donoso Luis , Pérez‐Sanagustín Mar , Neyem Andrés
Published: August 2018

Assessments in traditional university courses continue to be an accepted tool for validating the knowledge acquired in the different subjects. It is in this context that students use a variety of practices to prepare assessments and exams appropriately. On the other hand, in recent years, higher education institutions have been using the Massive Open Online Courses (MOOCs) as an alternative to expand and innovate their traditional classroom practices. In this field, some alternatives have been generated in these platforms to extend their functions beyond the courses proposed. MyMOOCSpace is a cloud‐based tool that improves the interaction of students participating in a MOOC course. However, a variation of this tool allows for improved collaboration and preparation of assessments and/or tests for students in a traditional higher education class. This article presents a study using the MyMOOCSpace tool as an alternative to encourage collaboration and preparation of students to take traditional tests or assessments in the field of higher education. To evaluate this application and demonstrate the impact on the results of the evaluations, a case study is presented in which 40 computer engineering students from a Chilean university participated. The results show that MyMOOCSpace generates a positive increase in student interaction regarding the subjects covered in the course, and that it helped them to study and prepare for the final exam of the subject.
Learn to apply EU's privacy rules to college athletics
Authors: O'Brien Timothy
Published: August 2018

The last thing coaches and athletics directors likely want to hear is the need to take more administrative steps to comply with yet another time‐consuming and complex law or regulation. Unfortunately, as it turns out, a new privacy law recently implemented by the European Union directly applies to schools and coaches involved in the recruitment and enrollment of international student‐athletes from Europe.
Carbaboranylation of Truncated C‐Terminal Neuropeptide Y Analogue Leads to Full hY1 Receptor Agonism
Authors: Hofmann Sven , Lindner Josephin , Beck‐Sickinger Annette G. , Hey‐Hawkins Evamarie , Bellmann‐Sickert Kathrin
Published: August 2018

The human Y1 receptor is overexpressed in breast tumour cells and is, therefore, a valuable target for site‐selective drug delivery. The well‐established hY1R‐selective ligand [Phe7,Pro34]NPY has been used to couple to drugs but its length of 36 amino acids also implies complex synthesis and high production costs. Therefore, shorter ligands are desirable. However, truncated versions of neuropeptide Y (NPY) usually result in reduced binding, antagonists, or only partial G‐protein‐biased agonists. Herein, we report on a nonamer peptide derived from the C terminus of NPY that is modified by a carbaborane, which is able to activate hY1R fully in terms of G‐protein activation but also arrestin recruitment and internalisation. We provide evidence that this unique behaviour is due to the bulky nature of the carbaborane cluster, which might address a specific second binding pocket in hY1R that is crucial for arrestin recruitment. Thus, this study helps in deciphering ligand‐induced onset of different pathways in hY1R mediated signalling.
The Role of Gender When Faculty Members Assign Consequences for Academic Dishonesty
Authors: Witmer Hope , Johansson Jonas
Published: August 2018

This chapter presents a gender perspective on the faculty members’ role in assigning discipline for academic dishonesty. Results of a study on this topic, along with recommendations for equitable practices, are included.
A Case Study in Updating Academic Integrity Policy and Procedures
Authors: Shane Mary Jo , Carson Loredana , Edwards Mark
Published: August 2018

This chapter discusses how a change model was used to create an updated academic integrity plan. A detailed account provides valuable information for any community college wanting to effectively implement such a plan.
Impact of simulated MitraClip on forward flow obstruction in the setting of mitral leaflet tethering: An in vitro investigation
Authors: Bloodworth Charles H. , Pierce Eric L. , Kohli Keshav , Deaton Nancy J. , Jones Kaitlin J. , Duvvuri Radhika , Kamioka Norihiko , Babaliaros Vasilis C. , Yoganathan Ajit P.
Published: August 2018

Objectives

We aimed to evaluate diastolic leaflet tethering as a factor that may cause mitral stenosis (MS) after simulated MitraClip implantation, using an in vitro left heart simulator.

Background

Leaflet tethering commonly seen in functional mitral regurgitation may be a significant factor affecting the severity of MS after MitraClip implantation.

Methods

A left heart simulator with excised ovine mitral valves (N = 6), and custom edge‐to‐edge clip devices (GTclip) was used to mimic implantation of MitraClip in a variety of positions. Anterior mitral leaflet (AML) tethering severity was varied for each case (leaflet excursion of 75°, 60°, and 45°, consistent with mild, moderate and severe tethering), and the baseline mitral annular area (MAA) was varied across samples (3.6–4.8 cm2). The resulting mitral valve area (MVA), and peak/mean mitral valve gradient (MVG) were measured in each case.

Results

AML tethering severity was a highly significant factor increasing MVG and decreasing MVA (P < 0.001). When GTclip placement was simulated with severe AML tethering, mean MVG >5 mmHg resulted more frequently than with GTclip placement alone (46% vs. 4%, respectively). However, severe AML tethering alone significantly reduced baseline MVA to 3.6 ± 0.2 cm2, and increased baseline MVG to 3.0 ± 0.4 mmHg. At MAA above 4.7 cm2, severe AML tethering did not cause moderate MS, even with placement of two GTclips (95% confidence).

Conclusions

Our results show that diastolic AML tethering may predispose to MS after clip placement, however, MS was not observed when baseline MVA was above 4.0 cm2. Severity of AML tethering may be an important criterion in selecting patients for edge‐to‐edge repair.
Massive air embolism as a complication of upper gastrointestinal endoscopy: A case report illustrating a stroke mimic, literature review, and suggested management
Authors: Kjellberg Anders , Nyström Harriet , Söderberg Martin , Dlugosz Aldona , Jörnvall Henrik , Steinberg Anna
Published: August 2018

Key Clinical Message

Cerebral air embolism should be considered in case of stroke symptoms during any invasive procedure. Transport to a hospital with neurosurgical/hyperbaric oxygen treatment (HBOT) facility could improve the outcome for the patient. Absence of air on computed tomography (CT) scan should not disqualify a patient from HBOT if air embolism is suspected.
Visible‐Light‐Driven Photocatalytic Oxidation of Organic Chlorides Using Air and an Inorganic‐Ligand Supported Nickel‐Catalyst Without Photosensitizers
Authors: Yu Han , Wang Jingjing , Zhai Yongyan , Zhang Mengqi , Ru Shi , Han Sheng , Wei Yongge
Published: August 2018

Engineering photoredox‐triggered chemical transformation via visible light has been an emerging area in organic synthesis. However, most of the well‐established photocatalysts are based upon either transition metal complexes involved with noble metals and organic ligands or photosensitive organic dyes, the development of pure inorganic molecular photocatalysts that could provide better stability and durability is greatly retarded. Herein we discover that the Anderson polyoxometalate (POM) Na4[NiMo6O18(OH)6] (1), which consists of pure inorganic framework built from a central NiII core supported by six MoVIO6 inorganic scaffold/ligands, can be used as a powerful photocatalyst. Upon irradiation with visible light (>400 nm), the compound can catalyze, in high efficiency, a wide range of reactions, including the oxidative cross‐coupling reaction of chlorides with amines, as well as oxidation of chlorides using molecular oxygen, affording various imines, aldehydes, and ketones, respectively in high selectivity and good yields. Owing to the robust inorganic framework, this catalyst exhibits excellent stability during the catalysis and reusability with little loss of the catalytic activity, thus providing an alternative without use of complicated organic ligands and expensive noble metal‐based photosensitizers.
Ceria‐Zirconia/Zeolite Bifunctional Catalyst for Highly Selective Conversion of Syngas into Aromatics
Authors: Huang Zhen , Wang Sheng , Qin Feng , Huang Liang , Yue Yinghong , Hua Weiming , Qiao Minghua , He Heyong , Shen Wei , Xu Hualong
Published: August 2018

Ceria‐zirconia solid solutions with tunable surface oxygen vacancy have been used in the direct conversion of syngas into aromatics after coupling with ZSM‐5 zeolite. A high selectivity of 83.1 % to aromatics has been achieved from syngas with low H2/CO ratio over Ce0.2Zr0.8O2/ZSM‐5 bifunctional catalyst. The surface oxygen vacancy of Ce0.2Zr0.8O2 is supposed to facilitate the formation of oxygenates which act as intermediates for C−C coupling and aromatization on ZSM‐5, and thus contribute to the well kinetic matching between C−O activation and C−C coupling over these two components of catalyst. The ceria‐zirconia with abundant surface oxygen vacancies and enhanced lattice oxygen mobility intimately mixed with ZSM‐5 zeolite with moderate acidity and crystal size play an important role in the catalytic performance.
Aminal‐based Hypercrosslinked Polymer Modified with Small Palladium Nanoparticles for Efficiently Catalytic Reduction of Nitroarenes
Authors: Xu Dan , Wang Fushan , Yu Guiqin , Zhao Hong , Yang Jing , Yuan Man , Zhang Xiaoyun , Dong Zhengping
Published: August 2018

Fabrication of heterogeneous catalysts with excellent activity, selectivity and stability is significant for various catalytic applications. Here, we prepared a hypercrosslinked polymer (HCP) via a facile and cost‐effective strategy using ferrocenecarboxaldehyde and melamine as building blocks. Then, the HCP was modified with highly dispersed ultrafine Pd nanoparticles (Pd/HCP). The obtained Pd/HCP shows excellent catalytic activity in the catalytic reduction of nitroarenes under mild reaction conditions. It′s worth mentioning that the N atoms in the HCP can efficiently coordinate Pd ions to form small Pd nanoparticles (NPs) and subsequently prevent the aggregation and leaching of Pd NPs during the reaction, so the Pd/HCP catalyst is highly stable and can be reused at least eight cycles without loss of catalytic activity. Therefore, this work may provide possibilities for using HCPs as ideal supporting materials for fabricating highly stable and efficient heterogeneous catalysts.