bluuebunny/crossref_metadata_2025 huggingface dataset:
Superexchange Effects on Oxygen Reduction Activity of Edge‐Sharing [CoxMn1−xO6] Octahedra in Spinel Oxide
Authors: Zhou Ye , Sun Shengnan , Xi Shibo , Duan Yan , Sritharan Thirumany , Du Yonghua , Xu Zhichuan J.
Published: January 2018

Mn–Co containing spinel oxides are promising, low‐cost electrocatalysts for the oxygen reduction reaction (ORR). Most studies are devoted to the design of porous Mn–Co spinels or to strongly coupled hybrids (e.g., MnCo2O4/N‐doped‐rmGO) to maximize the mass efficiency. The lack of analyses by metal oxide intrinsic activity (activity normalized to catalysts' surface area) hinders the development of fundamental understanding of the physicochemical principles behind the catalytic activities. A systematic study on the composition dependence of ORR in ZnCoxMn2−xO4 (x = 0.0–2.0) spinel is presented here with special attention to the role of edge sharing [CoxMn1−xO6] octahedra in the spinel structure. The ORR specific activity of ZnCoxMn2−xO4 spans across a potential window of 200 mV, indicating an activity difference of ≈3 orders of magnitude. The curve of composition‐dependent ORR specific activity as a function of Co substitution exhibits a volcano shape with an optimum Mn/Co ratio of 0.43. It is revealed that the modulated eg occupancy of active Mn cations (0.3–0.9), as a consequence of the superexchange effect between edge sharing [CoO6] and [MnO6], reflects the ORR activity of edge sharing [CoxMn1−xO6] octahedra in the ZnCoxMn2−xO4 spinel oxide. These findings offer crucial insights in designing spinel oxide catalysts with fine‐tuned eg occupancy for efficient catalysis.
Scalable 2D Hierarchical Porous Carbon Nanosheets for Flexible Supercapacitors with Ultrahigh Energy Density
Authors: Yao Lei , Wu Qin , Zhang Peixin , Zhang Junmin , Wang Dongrui , Li Yongliang , Ren Xiangzhong , Mi Hongwei , Deng Libo , Zheng Zijian
Published: January 2018

2D carbon nanomaterials such as graphene and its derivatives, have gained tremendous research interests in energy storage because of their high capacitance and chemical stability. However, scalable synthesis of ultrathin carbon nanosheets with well‐defined pore architectures remains a great challenge. Herein, the first synthesis of 2D hierarchical porous carbon nanosheets (2D‐HPCs) with rich nitrogen dopants is reported, which is prepared with high scalability through a rapid polymerization of a nitrogen‐containing thermoset and a subsequent one‐step pyrolysis and activation into 2D porous nanosheets. 2D‐HPCs, which are typically 1.5 nm thick and 1–3 µm wide, show a high surface area (2406 m2 g−1) and with hierarchical micro‐, meso‐, and macropores. This 2D and hierarchical porous structure leads to robust flexibility and good energy‐storage capability, being 139 Wh kg−1 for a symmetric supercapacitor. Flexible supercapacitor devices fabricated by these 2D‐HPCs also present an ultrahigh volumetric energy density of 8.4 mWh cm−3 at a power density of 24.9 mW cm−3, which is retained at 80% even when the power density is increased by 20‐fold. The devices show very high electrochemical life (96% retention after 10000 charge/discharge cycles) and excellent mechanical flexibility.
3D, Reconfigurable, Multimodal Electronic Whiskers via Directed Air Assembly
Authors: Reeder Jonathan T. , Kang Tong , Rains Sarah , Voit Walter
Published: January 2018

A batch‐assembly technique for forming 3D electronics on shape memory polymer substrates is demonstrated and is used to create dense, highly sensitive, multimodal arrays of electronic whiskers. Directed air flow at temperatures above the substrate's glass transition temperature transforms planar photolithographically defined resistive sensors from 2D precursors into shape‐tunable, deterministic 3D assemblies. Reversible 3D assembly and flattening is achieved by exploiting the shape memory properties of the substrate, enabling context‐driven shape reconfiguration to isolate/enhance specific sensing modes. In particular, measurement schemes and device configurations are introduced that allow for the sensing of temperature, stiffness, contact force, proximity, and surface texture and roughness. The assemblies offer highly spatiotemporally resolved, wide‐range measurements of surface topology (50 nm to 500 µm), material stiffness (200 kPa to 7.5 GPa), and temperature (0–100 °C), with response times of <250 µs. The development of a scalable process for 3D assembly of reconfigurable electronic sensors, as well as the large breadth and sensitivity of complex sensing modes demonstrated, has applications in the growing fields of 3D assembly, electronic skin, and human–machine interfaces.
Improved Performance of Zinc Oxide Thin Film Transistor Pressure Sensors and a Demonstration of a Commercial Chip Compatibility with the New Force Sensing Technology
Authors: Vishniakou Siarhei , Chen Renjie , Ro Yun Goo , Brennan Christopher J. , Levy Cooper , Yu Edward T. , Dayeh Shadi A.
Published: January 2018

A zinc oxide thin film transistor is developed and optimized that simultaneously functions as a transistor and a force sensor, thus allowing for scalable integration of sensors into arrays without the need for additional addressing elements. Through systematic material deposition, microscopy, and piezoelectric characterization, it is determined that an O2 rich deposition condition improves the transistor performance and pressure sensing characteristics. With these optimizations, a sensitivity of 4 nA kPa−1 and a latency of below 1 ms are achieved, exceeding the criteria for successful commercialization of arrayed pressure sensors. The functionality of 16 × 16 pressure sensor arrays on thin bendable glass substrates for integrated low weight and flexible touchscreen displays is fabricated and demonstrated and read‐out electronics to interface with the arrays and to record their response in real‐time are developed. Finally, the application of these sensors for mobile displays via their operation with an existing commercial touch integrated circuit controller is demonstrated.
The Catalyst‐Controlled Divergent Cascade Reactions of Homo‐Propargylic Amines and Nitrones: Synthesis of Pyrrolo‐Isoxazolidines and γ‐Lactams
Authors: Kong Yuanfang , Liu Yingze , Wang Boyi , Li Shengli , Liu Lingyan , Chang Weixing , Li Jing
Published: January 2018

Two controllable one‐pot cascade cyclization reactions of homopropargylic amines and nitrones were developed by using different metal Cu and Ag salts. The pyrroloisoxazolidines and γ‐lactams were obtained in good to high yields, respectively. Herein, nitrones played dual roles, both as 1,3‐dipoles and oxidants, and four stereocenters were simultaneously formed in the hydroamination cyclization‐1,3‐dipolar cycloaddition cascade reaction of homopropargylic amines and nitrones in the presence of AgOAc.

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Establishment of highly effective flame‐retardant unsaturated polyester resin system based on multiple strategies
Authors: Jiang Guo , Chen Liang , Jiang Saihua , Zhou Keqing , Shi Xingxing , Mou Wenjie
Published: January 2018

Considered that unsaturated polyester resin (UPR) as one of the most commonly used thermoset materials often exhibit severe fire hazards, graphene can be used to act as barriers to enhance the flame retardancy ofUPR. However, graphene easily shows irreversible aggregation when being introduced into polymer matrix, which limits its further application in industry. In this work, we synthesized a novel organophosphorus oligomer (DHP), which contained double bond and multivalent phosphorus (−1 and +5) with highly effective flame retardancy, onto graphene oxide via in situ atom‐transfer radical polymerization (ATRP). Then, the obtained graphene‐DHPwas incorporated intoUPRmatrix by curing. The homogeneous dispersion of graphene‐DHPinUPRmatrix was confirmed by transmission electron microscopy (TEM). The addition of 2.0 wt% graphene‐DHPsignificantly improved the flame retardancy ofUPR/graphene‐DHPnanocomposites, which was demonstrated by the peak of heat release rate (PHRR) decreased by 41.79%. Moreover, it is found that graphene‐DHPin nanocomposites cannot only act as barriers, but also catalyze the char formation in condensed phase as well as capture free radicals in gaseous phase. This work provides a feasible approach to combine graphene and phosphorus‐containing flame retardant and would also trigger more scientific interest in exploiting new type nanocomposites for flame retardants.
Decoupling Photocurrent Loss Mechanisms in Photovoltaic Cells Using Complementary Measurements of Exciton Diffusion
Authors: Curtin Ian J. , Holmes Russell J.
Published: January 2018

Significant work has been directed at measuring the exciton diffusion length (LD) in organic semiconductors due to its significance in determining the performance of photovoltaic cells. Several techniques have been developed to measure LD, often probing photoluminescence or charge carrier generation. Interestingly, in this study it is shown that when different techniques are compared, both the diffusive behavior of the exciton and active carrier recombination loss pathways can be decoupled. Here, a planar heterojunction device based on the donor–acceptor pairing of boron subphthalocyanine chloride‐C60 is examined using photoluminescence quenching, photovoltage‐, and photocurrent‐based LD measurement techniques. Photovoltage yields the device relevant LD of both active materials as a function of forward bias subject to geminate recombination losses. These values are used to accurately predict the photocurrent as a function of voltage, suggesting geminate recombination is the dominant mechanism responsible for photocurrent loss. By combining these measurements with photocurrent and photoluminescence quenching, the intrinsic LD, as well as the voltage‐dependent charge transfer state dissociation and charge collection efficiencies are quantitatively determined. The results of this work provide a method to decouple all relevant loss pathways during photoconversion, and establish the factors that can limit the performance of excitonic photovoltaic cells.
Lithiation Mechanism of Methylated Amorphous Silicon Unveiled by Operando ATR‐FTIR Spectroscopy
Authors: Koo Bon Min , Corte Daniel Alves Dalla , Chazalviel Jean‐Noël , Maroun Fouad , Rosso Michel , Ozanam François
Published: January 2018

The lithiation mechanism of methylated amorphous silicon, a‐Si1−x(CH3)x:H, with various methyl contents (x = 0 ‐ 0.12) is investigated using operando attenuated total reflection Fourier transform infrared spectroscopy. As in hydrogenated amorphous silicon, a‐Si:H, the first lithiation proceeds via a two‐phase mechanism. The concentration of the invading Li‐rich phase nonmonotonously depends on the methyl content of the active material. This behavior is tentatively explained by two distinct effects: a softening of the material due to a methyl‐induced lowering of its reticulation degree and its cohesion, and the presence of nanovoids at high enough methyl content.
Efficient Perovskite Photovoltaic‐Thermoelectric Hybrid Device
Authors: Xu Ling , Xiong Yan , Mei Anyi , Hu Yue , Rong Yaoguang , Zhou Yinhua , Hu Bin , Han Hongwei
Published: January 2018

An efficient perovskite photovoltaic‐thermoelectric hybrid device is demonstrated by integrating the hole‐conductor‐free perovskite solar cell based on TiO2/ZrO2/carbon structure and the thermoelectric generator. The whole solar spectrum of AM 1.5 G is fully utilized with the ≈1.55 eV band gap perovskite (5‐AVA)x(MA)1−xPbI3 absorbing the visible light and the carbon back contact absorbing the infrared light. The added thermoelectric generator improves the device performance by converting the thermal energy into electricity via the Seebeck effect. An optimized hybrid device is obtained with a maximum point power output of 20.3% and open‐circuit voltage of 1.29 V under the irradiation of 100 mW cm−2.
Diffraction‐Grated Perovskite Induced Highly Efficient Solar Cells through Nanophotonic Light Trapping
Authors: Wang Yang , Wang Peng , Zhou Xue , Li Chang , Li Huizeng , Hu Xiaotian , Li Fengyu , Liu Xiaoping , Li Mingzhu , Song Yanlin
Published: January 2018

Achieving light harvesting is crucial for the efficiency of the solar cell. Constructing optical structures often can benefit from micro‐nanophotonic imprinting. Here, a simple and facile strategy is developed to introduce a large area grating structure into the perovskite‐active layer of a solar cell by utilizing commercial optical discs (CD‐R and DVD‐R) and achieve high photovoltaic performance. The constructed diffraction grating on the perovskite active layer realizes nanophotonic light trapping by diffraction and effectively suppresses carrier recombination. Compared to the pristine perovskite solar cells (PSCs), the diffraction‐grating perovskite devices with DVD obtain higher power conversion efficiency and photocurrent density, which are improved from 16.71% and 21.67 mA cm−2 to 19.71% and 23.11 mA cm−2. Moreover, the stability of the PSCs with diffraction‐grating‐structured perovskite active layer is greatly enhanced. The method can boost photonics merge into the remarkable perovskite materials for various applications.
Rapid and Efficient Generation of Stable Antibody–Drug Conjugates via an Encoded Cyclopropene and an Inverse‐Electron‐Demand Diels–Alder Reaction
Authors: Oller‐Salvia Benjamí , Kym Gene , Chin Jason W.
Published: January 2018

Homogeneous antibody–drug conjugates (ADCs), generated by site‐specific toxin linkage, show improved therapeutic indices with respect to traditional ADCs. However, current methods to produce site‐specific conjugates suffer from low protein expression, slow reaction kinetics, and low yields, or are limited to particular conjugation sites. Here we describe high yielding expression systems that efficiently incorporate a cyclopropene derivative of lysine (CypK) into antibodies through genetic‐code expansion. We express trastuzumab bearing CypK and conjugate tetrazine derivatives to the antibody. We show that the dihydropyridazine linkage resulting from the conjugation reaction is stable in serum, and generate an ADC bearing monomethyl auristatin E that selectively kills cells expressing a high level of HER2. Our results demonstrate that CypK is a minimal bioorthogonal handle for the rapid production of stable therapeutic protein conjugates.
Design of Metal‐Free Polymer Carbon Dots: A New Class of Room‐Temperature Phosphorescent Materials
Authors: Tao Songyuan , Lu Siyu , Geng Yijia , Zhu Shoujun , Redfern Simon A. T. , Song Yubin , Feng Tanglue , Xu Weiqing , Yang Bai
Published: January 2018

Polymer carbon dots (PCDs) are proposed as a new class of room‐temperature phosphorescence (RTP) materials. The abundant energy levels in PCDs increase the probability of intersystem crossing (ISC) and their covalently crosslinked framework structures greatly suppress the nonradiative transitions. The efficient methods allow the manufacture of PCDs with unique RTP properties in air without additional metal complexation or complicated matrix composition. They thus provide a route towards the rational design of metal‐free RTP materials that may be synthesized easily. Furthermore, we find that RTP is associated with a crosslink‐enhanced emission (CEE) effect, which provides further routes to design improved PCDs with diverse RTP performance. Our results show the potential of PCDs as a universal route to achieve effective metal‐free RTP.
Stable Enantiomers Displaying Thermally Activated Delayed Fluorescence: Efficient OLEDs with Circularly Polarized Electroluminescence
Authors: Li Meng , Li Si‐Hua , Zhang Dongdong , Cai Minghan , Duan Lian , Fung Man‐Keung , Chen Chuan‐Feng
Published: January 2018

Aromatic‐imide‐based thermally activated delayed fluorescent (TADF) enantiomers, (+)‐(S,S)‐CAI‐Cz and (−)‐(R,R)‐CAI‐Cz, were efficiently synthesized by introducing a chiral 1,2‐diaminocyclohexane to the achiral TADF unit. The TADF enantiomers exhibited high PLQYs of up to 98 %, small ΔEST values of 0.06 eV, as well as obvious temperature‐dependent transient PL spectra, thus demonstrating their excellent TADF properties. Moreover, the TADF enantiomers showed mirror‐image CD and CPL activities. Notably, the CP‐OLEDs with CPEL properties based on the TADF enantiomers not only achieved high EQE values of up to 19.7 and 19.8 %, but also displayed opposite CPEL signals with gEL values of −1.7×10−3 and 2.3×10−3, which represents the first CP‐OLEDs, based on the enantiomerically pure TADF materials, having both high efficiencies and intense CPEL.
Kinetic Analysis and Structural Interpretation of Competitive Ligand Binding for NO Dioxygenation in Truncated Hemoglobin N
Authors: Das Akshaya Kumar , Meuwly Markus
Published: January 2018

The conversion of nitric oxide (NO) into nitrate (NO3−) by dioxygenation protects cells from lethal NO. Starting from NO‐bound heme, the first step in converting NO into benign NO3− is the ligand exchange reaction FeNO+O2→FeO2+NO, which is still poorly understood at a molecular level. For wild‐type (WT) truncated hemoglobin N (trHbN) and its Y33A mutant, the calculated barriers for the exchange reaction differ by 1.5 kcal mol−1, compared with 1.7 kcal mol−1 from experiment. It is directly confirmed that the ligand exchange reaction is rate‐limiting in trHbN and that entropic contributions account for 75 % of the difference between the WT and the mutant. Residues Tyr 33, Phe 46, Val 80, His 81, and Gln 82 surrounding the active site are expected to control the reaction path. By comparison with electronic structure calculations, the transition state separating the two ligand‐bound states was assigned to a 2A state.
Effect of stereoisomerism of poly(lactic acid) during neural guide conduit membrane synthesis
Authors: Domingues Rui Carlos Castro , Pereira Cristina Cardoso , Borges Cristiano Piacsek
Published: January 2018

Poly(lactic acid) membranes are being developed as biomaterials for several purposes such as artificial implants for peripheral nerve injury, also known as neural guide conduits (NGC). These membranes need to meet standards of mechanical, degradability, and permeability properties, besides dimensional and structural requirements. Among the stereoisomers of polylactides, poly(l‐lactic acid), and poly(d,l‐lactic acid) are the most used as biomaterials, having significant differences in solubility, crystallinity thermal, and mechanical properties. In this work, PLLA and PDLLA were compared for hollow fiber membrane synthesis by liquid induced phase separation. PLLA samples presented 18% of crystallinity, while PDLLA is amorphous. PDLLA and PLLA polymer solutions on N‐methyl‐pyrrolidone presented values of 3428 and 320.2 cP, respectively. In immersion of PLA‐NMP solutions in water, PLLA solution presented instantaneous demixing, while PDLLA showed a 28 s delay on precipitation. The PLLA–NMP–water has a larger demixing region compared to PDLLA–NMP–water system. Hollow fibers of both polymers presented closed external surface with finger‐like macropores morphology in their cross‐sections. PDLLA presented typical liquid–liquid demixing pores while PLLA presented spherulitical crystalline solid–liquid separation structures, which deeply compromised its mechanical properties. PDLLA presented as a good candidate for hollow fiber NGC material, as presented good mechanical resistance in tensile and suture simulating tests. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46190.
[(18‐Crown‐6)K][Fe(1)Cl(1)4]0.5[Fe(2)Cl(2)4]0.5: A Multifunctional Molecular Switch of Dielectric, Conductivity and Magnetic Properties
Authors: Tong Yuan‐Bo , Tian Zheng‐Fang , Duan Hai‐Bao , Zhu Zhong‐Peng , He Wei , Hong Tian‐Yu , Yu Gui , He Yu‐Jian , Yang Jing‐Kui
Published: January 2018

Multifunctional materials that exhibit different physical properties in a single phase have potential for use in multifunctional devices. Herein, we reported an organic–inorganic hybrid compound [(18‐crown‐6)K][Fe(1)Cl(1)4]0.5[Fe(2)Cl(2)4]0.5 (1) by incorporating KCl and FeCl3 into a 18‐crown‐6 molecule, which acts as a host of the six O atoms providing a lone pair of electrons to anchor the guest potassium cation, and [FeCl4]− as a counterion for charge balance to construct a complex salt. This salt exhibited a one‐step reversible structural transformation giving two separate high and low temperature phases at 373 K, which was confirmed by systematic characterizations including differential scanning calorimetry (DSC) measurements, variable‐temperature structural analyses, and dielectric, impedance, variable‐temperature magnetic susceptibility measurements. Interestingly, the structural transformation was coupled to both hysteretic dielectric phase transition, conductivity switch and magnetic‐phase transition at 373 K. This result gives an idea for designing a new type of phase‐transition materials harboring technologically important magnetic, conductivity and dielectric properties.
Precision Fluorescent Labeling of an Adeno‐Associated Virus Vector to Monitor the Viral Infection Pathway
Authors: Zhang Chuanling , Zhou Xueying , Yao Tianzhuo , Tian Zhenyu , Zhou Demin
Published: January 2018

Adeno‐associated virus 2 (AAV2) is a common vehicle for the delivery of a variety of therapeutic genes. A better understanding of the process of infection of AAV2 will advance our knowledge of AAV2 biology and allow for the optimization of AAV2 capsids with favorable transduction profiles. However, the precise fluorescent labeling of an AAV2 vector for probing virus tracking without affecting the nature of the virus remains a challenge. In this study, a lab‐synthesized azide‐moieties on the viral capsid at modifiable sites is precisely displayed. Upon bioorthogonal copper‐less click reaction, fluorophores are subsequently conjugated to AAV2 vectors for visualization of particles. Using this principle, the authors demonstrate that it can be used for visibly studying the cell entry, and intracellular trafficking of AAV2 particles, enabling the monitoring of the intracellular dynamics of AAV2 infection. This study provides new insights into the precision labeling of AAV2 particles with important implications for a better understanding of the molecular mechanism of therapeutic gene delivery.
Accurate determination of a novel vasodilatory β‐blocker TJ0711 using LC‐MS/MS: Resolution of an isobaric metabolite interference in dog plasma
Authors: Hu Yang , Zhu Wenwen , Guan Yeli , Wu Sanlan , Zhang Xiaoyin , Li Gao , Si Luqin , Huang Jiangeng
Published: January 2018

A rapid, robust and sensitive liquid chromatography–tandem mass spectrometry method was developed and validated for bioanalysis of TJ0711, a novel vasodilatory β‐blocker in dog plasma. This assay is able to chromatographically separate TJ0711 from its isobaric metabolite as well as glucuronide conjugates. Chromatographic separation was achieved on a Welch Ultimate‐XB C18 column (2.1 × 100 mm, 3 μm). The analyte and internal standard (propranolol) were extracted from plasma by liquid–liquid extraction using ethyl acetate. The mass spectrometric detection was carried out in positive ion multiple reaction monitoring mode. Good linearity was obtained over the concentration range of 0.5–500 ng/mL (r > 0.99) for TJ0711. Moreover, the method had good accuracy (RE ranging from −2.70 to −0.32%) and precision (RSD < 7.55%). TJ0711 was stable in dog plasma for at least 6 h at ambient temperature, for at least 30 days at −20°C and after three freeze–thaw cycles. This method was successfully applied to a preclinical pharmacokinetic study and the results demonstrated linear pharmacokinetics of TJ0711 over a dose range from 0.03 to 0.3 mg/kg. No significant gender differences were observed in TJ0711 plasma pharmacokinetic parameters.
Six New Polyhydroxysteroidal Glycosides, Anthenosides S1 – S6, from the Starfish Anthenea sibogae
Authors: Kicha Alla A. , Ha Dinh T. , Ivanchina Natalia V. , Malyarenko Timofey V. , Kalinovsky Anatoly I. , Dmitrenok Pavel S. , Ermakova Svetlana P. , Malyarenko Olesya S. , Hung Nguyen A. , Thuy Tran T. T. , Long Pham Q.
Published: January 2018

Six new polyhydroxysteroidal glycosides, anthenosides S1  – S6 (1 – 6), along with a mixture of two previously known related glycosides, 7 and 8, were isolated from the methanolic extract of the starfish Anthenea sibogae. The structures of 1 – 6 were established by NMR and HR‐ESI‐MS techniques as well as by chemical transformations. All new compounds have a 5α‐cholest‐8(14)‐ene‐3α,6β,7β,16α‐tetrahydroxysteroidal nucleus and differ from majority of starfish glycosides in positions of carbohydrate moieties at C(7) and C(16) (1 – 4, 6) or only at C(16) (5). The 4‐O‐methyl‐β‐d‐glucopyranose residue (2) and Δ24‐cholestane side chain (3) have not been found earlier in the starfish steroidal glycosides. The mixture of 7 and 8 slightly inhibited the proliferation of human breast cancer T‐47D cells and decreased the colony size in the colony formation assay.
A Modular Nanoswitch for Mix‐and‐Detect Protein Assay Based on Binding‐Induced Cascade Dissociation of Kissing Complex
Authors: Tian Yishen , Zhang Shanshan , Wang Li , Liu Shufeng
Published: January 2018

A new modular nanoswitch was described for versatile, rapid (within 1 h), homogeneous, and sensitive protein detection. The system employs two hairpins (HP1 and HP2) that can be reciprocally recognized through the apical loop–loop interaction. HP2 possesses a conformation‐switching stem–loop structure, with appended single‐stranded tails on each end, which can hybridize with the recognition‐element‐conjugated DNA strands to construct a protein‐responsive HP2 scaffold. It works according to a simple mix‐and‐detect assay format, with the first formation of a kissing complex between HP1 and HP2 scaffolds for fluorescence quenching, and then cascade propagation from steric strain through protein binding to the dissociation of the kissing complex for fluorescence recovery. The detection universality of such a modular nanoswitch was demonstrated by using three multivalent proteins, including anti‐digoxigenin (Anti‐Dig) antibody, streptavidin, and thrombin, with detection limits of 0.33, 0.17, and 0.5 nm, respectively.
Antiplatelet drug selection in PCI to vein grafts in patients with acute coronary syndrome and adverse clinical outcomes: Insights from the British Cardiovascular Intervention Society database
Authors: Sirker Alex , Kwok Chun Shing , Kontopantelis Evangelos , Johnson Tom , Freeman Philip , de Belder Mark A , Ludman Peter , Zaman Azfar , Mamas Mamas A
Published: January 2018

Objective

This study aims to evaluate outcomes associated with different P2Y12 agents in Saphenous Vein graft (SVG) percutaneous coronary intervention (PCI).

Background

SVG PCI is associated with greater risks of ischemic complications, compared with native coronary PCI. Outcomes associated with the use of potent P2Y12 blocking drugs, Prasugrel and Ticagrelor, in SVG PCI are unknown.

Methods

Patients included in the study underwent SVG PCI in the United Kingdom between 2007 and 2014 for acute coronary syndrome and were grouped by P2Y12 antiplatelet use. In‐hospital major adverse cardiac events, major bleeding and 30‐day and 1‐year mortality were examined. Multiple imputations with chained equations to impute missing data were used. Adjustment for baseline imbalances was performed using (1) multiple logistic regression (MLR) and (separately) (2) propensity score matching (PSM).

Results

Data weres analyzed from 8,119 patients and most cases were treated with Clopidogrel (n = 7,401), followed by Ticagrelor (n = 497) and Prasugrel (n = 221). In both MLR and PSM models, there was no significant evidence to suggest that either Prasugrel or Ticagrelor was associated with significantly lower 30‐day mortality compared with Clopidogrel. The odds ratios reported from the multivariable analysis were 1.22 (95% CI: 0.60–2.51) for Prasugrel vs. Clopidogrel and 0.48 (95% CI: 0.20–1.16) for Ticagrelor vs. Clopidogrel. No significant differences were seen for in‐hospital ischemic or bleeding events.

Conclusions

Our real world national study provides no clear evidence to indicate that use of potent P2Y12 blockers in SVG PCI is associated with improved clinical outcomes.
Effects of parboiling and other hydrothermal treatments on the physical, functional, and nutritional properties of rice and other cereals
Authors: Rocha‐Villarreal Verónica , Serna‐Saldivar Sergio O. , García‐Lara Silverio
Published: January 2018

Background and objectives

Parboiling is a hydrothermal treatment, rarely used in cereals other than rice, which consists in three sequential steps: grain conditioning or soaking, cooking, and drying. The aim of this process was to partially gelatinize the starch to seal fissures/cracks and therefore improve milling yield. This review aims to discuss the reported effects of parboiling and similar hydrothermal treatments on the physicochemical, nutritional, processing, and storage properties of rice but mostly of other cereals.

Findings

Independently of the type of cereal, parboiling leads to changes in physicochemical, nutritional, and technological properties. However, the standardization and commercial scaling of these processes have been limited.

Conclusions

The parboiling effect varies according to the grain intrinsic properties and the processing conditions. Some cereals behave similar to rice, but others are affected oppositely. Further research is needed to better understand the effects of parboiling and hydrothermal treatments in cereal grains, and for the development of a standardized methodology for hydrothermally treating grains.

Significance and novelty

The understanding of the effects and the proper implementation of these hydrothermal treatments in corn could lead to significant enhancements in grains properties that could play a key role to solve hunger, malnutrition, and related food security problems.
Characterizing whole‐wheat flours produced using a commercial stone mill, laboratory mills, and household single‐stream flour mills
Authors: Ross Andrew S. , Kongraksawech Teepakorn
Published: January 2018

Background and objectives

One hard wheat and one semi‐hard wheat were milled on commercial, laboratory, and household‐scale flour mills with rotating elements ranging from 0.1 to 1.0 m in diameter and speeds ranging from 65 to 40,000 rpm. The aim of the study was to assess and compare the quality of the flour from each of mills.

Findings

Pasting viscosities, Farinograph development time and stability, and loaf volumes (LVOL) were all markedly influenced by whole‐wheat flour particle size, which differed markedly between mills. LVOLs were acceptable using the flours produced by all the mills. Best flour quality came from the three mills that produced the finest whole‐wheat flour. Of these, the superior flour came from the 1.0‐m‐diameter Osttiroler stone mill. This mill produced whole‐wheat flours with more optimal levels of starch damage and higher water absorption than did the smaller mills. There was no evidence of degradation of gluten functionality even at a flour temperature of 51°C.

Conclusions

The mill used affected almost all flour quality traits. However, the characteristics of the wheat applied to the mill were the dominant influence on flour functionality. Starch damage may better indicate milling severity than the heat generated during the milling process.

Significance and novelty

This is the only study, that we know of, on the comparative performance of household‐scale flour mills. The study also presents an alternative way of visualizing particle size distributions of flours.
Factors affecting Asian wheat noodle color and time‐dependent discoloration—A review
Authors: Siah Siem , Quail Kenneth J.
Published: January 2018

Background and objectives

Wheat noodles are a staple food for many Asian populations, particularly in East and South‐East Asian countries. Fresh noodles are subject to discoloration or darkening over storage time if not cooked or preserved. The physical appearance of noodles has the very first and often most significant impact on consumer perception leading to purchasing decisions. This review paper outlines the different noodle types followed by discussing factors affecting noodle color and time‐dependent discoloration. Methods used for preserving noodle freshness and color are also discussed.

Findings

Wheat noodles are generally categorized as white salted noodles made with the addition of sodium chloride, and yellow alkaline noodles made with the addition of different combinations of sodium chloride and alkaline salts. The intrinsic factors relating to wheat and flour quality affecting noodle color and discoloration include protein content, wheat bran color, falling number and preharvest sprouting, ash content, polyphenol oxidase, carotenoids, phenolic compounds, and flour color. The extrinsic factors relating to processing parameters affecting noodle color and time‐dependent discoloration include selection of flour mill streams, flour milling extraction rates, starch damage, noodle processing methods, addition of different salt types, addition of eggs, gluten, starch and emulsifiers, water addition and absorption levels, and addition of plant materials.

Conclusions

It is important for manufacturers to select the right wheat type, processing methods, and formulation to produce noodles with desirable color appearance and less susceptible to time‐dependent discoloration.

Significance and novelty

This review paper details intrinsic factors relating to wheat and flour quality, and extrinsic factors relating to processing parameters that affect wheat noodle color and time‐dependent discoloration.
Recent Advances in Germanium‐Based Photoinitiator Chemistry
Authors: Haas Michael , Radebner Judith , Eibel Anna , Gescheidt Georg , Stueger Harald
Published: January 2018

Acylgermanes provide an outstanding photoinduced reactivity at very useful absorption wavelengths. This encouraged multidisciplinary research groups to utilize them as highly effective and non‐toxic photoinitiators particularly for medical applications. In this Minireview, we present the most recent breakthroughs to synthesize acylgermanes. We also outline mechanistic aspects of photoinduced reactions of several acylgermane derivatives based on fundamental spectroscopic insights. These studies may aid future developments for tailor‐made photoinitiators.
Copper‐Catalyzed Aziridination with Redox‐Active Ligands: Molecular Spin Catalysis
Authors: Ren Yufeng , Cheaib Khaled , Jacquet Jérémy , Vezin Hervé , Fensterbank Louis , Orio Maylis , Blanchard Sébastien , Desage‐El Murr Marine
Published: January 2018

Small‐molecule catalysts as mimics of biological systems illustrate the chemists’ attempts at emulating the tantalizing abilities displayed by nature's metalloenzymes. Among these innate behaviors, spin multistate reactivity is used by biological systems as it offers thermodynamic leverage towards challenging chemical reactivity but this concept is difficult to translate into the realm of synthetic organometallic catalysis. Here, we report a rare example of molecular spin catalysis involving multistate reactivity in a small‐molecule biomimetic copper catalyst applied to aziridination. This behavior is supported by spin state flexibility enabled by the redox‐active ligand.
Crystal Field in Rare‐Earth Complexes: From Electrostatics to Bonding
Authors: Alessandri Riccardo , Zulfikri Habiburrahman , Autschbach Jochen , Bolvin Hélène
Published: January 2018

The flexibility of first‐principles (ab initio) calculations with the SO‐CASSCF (complete active space self‐consistent field theory with a treatment of the spin‐orbit (SO) coupling by state interaction) method is used to quantify the electrostatic and covalent contributions to crystal field parameters. Two types of systems are chosen for illustration: 1) The ionic and experimentally well‐characterized PrCl3 crystal; this study permits a revisitation of the partition of contributions proposed in the early days of crystal field theory; and 2) a series of sandwich molecules [Ln(ηn‐CnHn)2]q, with Ln=Dy, Ho, Er, and Tm and n=5, 6, and 8, in which the interaction between LnIII and the aromatic ligands is more difficult to describe within an electrostatic approach. It is shown that a model with three layers of charges reproduces the electrostatic field generated by the ligands and that the covalency plays a qualitative role. The one‐electron character of crystal field theory is discussed and shown to be valuable, although it is not completely quantitative. This permits a reduction of the many‐electron problem to a discussion of the energy of the seven 4f orbitals.
Phenylboronic Acid Derivatives as Validated Leads Active in Clinical Strains Overexpressing KPC‐2: A Step against Bacterial Resistance
Authors: Celenza Giuseppe , Vicario Mattia , Bellio Pierangelo , Linciano Pasquale , Perilli Mariagrazia , Oliver Antonio , Blazquez Jesús , Cendron Laura , Tondi Donatella
Published: January 2018

The emergence and dissemination of multidrug resistant (MDR) pathogens resistant to nearly all available antibiotics poses a significant threat in clinical therapy. Among them, Klebsiella pneumoniae clinical isolates overexpressing KPC‐2 carbapenemase are the most worrisome, extending bacterial resistance to last‐resort carbapenems. In this study, we investigate the molecular recognition requirements in the KPC‐2 active site by small phenylboronic acid derivatives. Four new phenylboronic acid derivatives were designed and tested against KPC‐2. For the most active, despite their simple chemical structures, nanomolar affinity was achieved. The new derivatives restored susceptibility to meropenem in clinical strains overexpressing KPC‐2. Moreover, no cytotoxicity was detected in cell‐viability assays, which further validated the designed leads. Two crystallographic binary complexes of the best inhibitors binding KPC‐2 were obtained at high resolution. Kinetic descriptions of slow binding, time‐dependent inhibition, and interaction geometries in KPC‐2 were fully investigated. This study will ultimately lead toward the optimization and development of more‐effective KPC‐2 inhibitors.
Essential role of hippocampal noradrenaline in the regulation of spatial working memory and TDP‐43 tissue pathology
Authors: Pintus Roberta , Riggi Margherita , Cannarozzo Cecilia , Valeri Andrea , de Leo Gioacchino , Romano Maurizio , Gulino Rosario , Leanza Giampiero
Published: January 2018

Extensive loss of noradrenaline‐containing neurons and fibers is a nearly invariant feature of Alzheimer's Disease (AD). However, the exact noradrenergic contribution to cognitive and histopathological changes in AD is still unclear. Here, this issue was addressed following selective lesioning and intrahippocampal implantation of embryonic noradrenergic progenitors in developing rats. Starting from about 3 months and up to 12 months post‐surgery, animals underwent behavioral tests to evaluate sensory‐motor, as well as spatial learning and memory, followed by post‐mortem morphometric analyses. At 9 months, Control, Lesioned and Lesion + Transplant animals exhibited equally efficient sensory‐motor and reference memory performance. Interestingly, working memory abilities were seen severely impaired in Lesion‐only rats and fully recovered in Transplanted rats, and appeared partly lost again 2 months after ablation of the implanted neuroblasts. Morphological analyses confirmed the almost total lesion‐induced noradrenergic neuronal and terminal fiber loss, the near‐normal reinnervation of the hippocampus promoted by the transplants, and its complete removal by the second lesion. Notably, the noradrenergic‐rich transplants normalized also the nuclear expression of the transactive response DNA‐binding protein 43 (TDP‐43) in various hippocampal subregions, whose cytoplasmic (i.e., pathological) occurrence appeared dramatically increased as a result of the lesions. Thus, integrity of ascending noradrenergic inputs to the hippocampus may be required for the regulation of specific aspects of learning and memory and to prevent TDP‐43 tissue pathology.
Application of the Interacting Quantum Atoms Approach to the S66 and Ionic‐Hydrogen‐Bond Datasets for Noncovalent Interactions
Authors: Suárez Dimas , Díaz Natalia , Francisco Evelio , Martín Pendás Angel
Published: January 2018

The interacting quantum atoms (IQA) method can assess, systematically and in great detail, the strength and physics of both covalent and noncovalent interactions. The lack of a pair density in density functional theory (DFT), which precludes the direct IQA decomposition of the characteristic exchange–correlation energy, has been recently overcome by means of a scaling technique, which can largely expand the applicability of the method. To better assess the utility of the augmented IQA methodology to derive quantum chemical decompositions at the atomic and molecular levels, we report the results of Hartree–Fock (HF) and DFT calculations on the complexes included in the S66 and the ionic H‐bond databases of benchmark geometry and binding energies. For all structures, we perform single‐point and geometry optimizations using HF and selected DFT methods with triple‐ζ basis sets followed by full IQA calculations. Pairwise dispersion energies are accounted for by the D3 method. We analyze the goodness of the HF‐D3 and DFT‐D3 binding energies, the magnitude of numerical errors, the fragment and atomic distribution of formation energies, etc. It is shown that fragment‐based IQA decomposes the formation energies in comparable terms to those of perturbative approaches and that the atomic IQA energies hold the promise of rigorously quantifying atomic and group energy contributions in larger biomolecular systems.
The Controversial Orientation of Adenine on Gold and Silver
Authors: Harroun Scott G.
Published: January 2018

In which orientation does adenine adsorb on gold and silver surfaces? This question has been a matter of debate for over 30 years. Since the dawn of surface‐enhanced Raman spectroscopy (SERS); it and other techniques such as tip‐enhanced Raman spectroscopy (TERS), surface‐enhanced infrared absorption spectroscopy (SEIRAS), scanning tunneling microscopy (STM), density functional theory (DFT) simulations, and more, have been used in many attempts to answer this seemingly straightforward, yet controversial, question. Herein, the timeline and recent advances on this topic are explored, and the frequently contradictory findings are put into context and discussed.
Room Temperature Synthesis of Graphene Nanosheets
Authors: Mandal Peetam , Naik M. Jaya Prakash , Saha Mitali
Published: January 2018

The domain of graphene's application is highly multifaceted in the recent years but developing quintessential quality of graphene is quite challenging for industrial sectors via facile route. In this article, an indigenous one step production of graphene from graphite powder by mere stirring and using eco‐friendly aqueous solvent is reported. This fabrication process also bypass the conventional multistep involved previously. The role of sodium dodecyl sulfate (SDS) as a surfactant and the effect of stirring at different time intervals are studied, which clearly indicates that the surfactant facilitates the dispersion of the precursor in water at room temperature and the prolonged stirring helps to break the labile van der Waals forces within the graphitic structure.
Invincible AODV to detect black hole and gray hole attacks in mobile ad hoc networks
Authors: Sandhya Venu Vasantha , Avula Damodaram
Published: January 2018

Today's communication world is majorly driven by mobile nodes that demand wireless systems for their data relay. One such network is mobile ad hoc network, which is a purely wireless network with which communication is feasible instantly without any aid of preexisting infrastructure; due to this magnificent feature, it has a wide variety of applications. Mobile ad hoc network hinges on cooperative nature of the mobile nodes for relaying data. But at the same time, nodes relaying data for others may compromise, leading to various security attacks. Two main security attacks that drastically bring down the performance of mobile ad hoc network are black hole and gray hole attacks. In this paper, we propose 2 versions of invincible Ad hoc On‐Demand Distance Vector protocol to detect black hole and gray hole nodes that have bypassed preventive mechanism during route discovery process. First is the basic version, which is based on node‐to‐node frame check sequence tracking mechanism, and second is the enhanced version, which is based on signed frame check sequence tracking mechanism. They create a deterrent environment addressing all kinds of black and gray hole attacks. They also provide reliable data transmission to all the nonmalicious nodes in the network by using end‐to‐end authentication mechanism. Simulation results show better performance in packet delivery ratio when compared with other contemporary solutions while addressing all kinds of black and gray hole attacks. It shows significant improvement in end‐to‐end delay and normalized routing load over Ad hoc On‐Demand Distance Vector under black hole or gray hole attacks and also shows better throughput and packet delivery ratio than the existing solution.
Pass the baton of leadership with grace
Authors: Hodges Dawn Z.
Published: January 2018

Later this year I will retire. It is time for me to pass the baton to my successor. I will be doing so very soon. It will happen prior to my retirement. Because my successor and I will be on campus at the same time, it is extremely important that I pass the baton with grace and dignity.
Disability resources in higher education, part 1: Budget and finance fundamentals
Authors: Thompson Tom L.
Published: January 2018

If you listen carefully, you can hear groans and sounds of exasperation coming from provost or chief student affairs officer offices! Why? They have just received news from their Disability Resources and Services Office that $25,000 is needed for a book to be produced in Braille, or that a deaf medical student's interpreting and captioning is estimated to cost $40,000.
Temporal heterogeneity increases with spatial heterogeneity in ecological communities
Authors: Collins Scott L. , Avolio Meghan L. , Gries Corinna , Hallett Lauren M. , Koerner Sally E. , La Pierre Kimberly J. , Rypel Andrew L. , Sokol Eric R. , Fey Samuel B. , Flynn Dan F. B. , Jones Sydney K. , Ladwig Laura M. , Ripplinger Julie , Jones Matt B.
Published: January 2018

Heterogeneity is increasingly recognized as a foundational characteristic of ecological systems. Under global change, understanding temporal community heterogeneity is necessary for predicting the stability of ecosystem functions and services. Indeed, spatial heterogeneity is commonly used in alternative stable state theory as a predictor of temporal heterogeneity and therefore an early indicator of regime shifts. To evaluate whether spatial heterogeneity in species composition is predictive of temporal heterogeneity in ecological communities, we analyzed 68 community data sets spanning freshwater and terrestrial systems where measures of species abundance were replicated over space and time. Of the 68 data sets, 55 (81%) had a weak to strongly positive relationship between spatial and temporal heterogeneity, while in the remaining communities the relationship was weak to strongly negative (19%). Based on a mixed model analysis, we found a significant but weak overall positive relationship between spatial and temporal heterogeneity across all data sets combined, and within aquatic and terrestrial data sets separately. In addition, lifespan and successional stage were negatively and positively related to temporal heterogeneity, respectively. We conclude that spatial heterogeneity may be a predictor of temporal heterogeneity in ecological communities, and that this relationship may be a general property of many terrestrial and aquatic communities.