bluuebunny/crossref_metadata_2025 huggingface dataset:
Gegensätzliche Reaktionsweisen magnesium‐ und zinkbasierter Germaniumnukleophile in der C(sp3)‐Ge‐Kreuzkupplung mit Alkylelektrophilen
Authors: Xue Weichao , Mao Wenbin , Zhang Liangliang , Oestreich Martin
Published: March 2019

Es wird über robuste Reaktionsvorschriften zweier mechanistisch ungleicher C(sp3)‐Ge‐Bindungsknüpfungen ausgehend von Alkylelektrophilen und Germaniumnukleophilen berichtet. Die Germaniumreagenzien stehen nach Lithium‐auf‐Magnesium‐ bzw. Lithium‐auf‐Zink‐Ummetallierung als stabile Stammlösungen zur Verfügung. Das Germanium‐Grignard‐Reagens reagiert mit mehreren 1° und 2° Alkylelektrophilen in einem ionischen nukleophilen Austausch. Im Gegensatz dazu erfordert die Kupplung des entsprechenden Zinkreagens einen Nickelkatalysator, und jenes nimmt dann an radikalischen Bindungsknüpfungen mit 1°, 2° und selbst 3° Alkylbromiden teil. Beide Methoden umgehen das Regioselektivitätsproblem der Hydrogermylierung von Alkenen und ermöglichen die Darstellung einer breiten Palette funktionalisierter alkylsubstituierter Germane.
Photoprintable nanowire–polymer blends synthesized by dynamic emulsion polycondensation
Authors: Zhang Linqi , Karumuri Sriharsha , Alavi S. Habib , Bai He , Harimkar Sandip P. , Kalkan A. Kaan
Published: March 2019

In this article, we report a photoprintable nanocomposite synthesized at room temperature in less than 10 s by aggressive mixing of two monomer solutions. Polycondensation occurs in the dispersed phase of the dynamic emulsion, microdroplets, in which the nanofillers are suspended. Hence, the synthesized composite microparticles have a high dispersion and high loading of nanofillers. Specifically, silver nanowire (AgNW)–nylon 66 blends with various Ag weight fractions are synthesized and studied. The poly(vinyl pyrrolidone) (PVP)‐functionalized AgNWs (by polyol synthesis) are singly dispersed and tethered to the nylon matrix by PVP with a slight depression of the glass‐transition temperature. The Ag–nylon powder melts under low‐intensity visible continuous wave laser radiation; this allows convenient photoprinting of the nanocomposite structures. Photoprinting is demonstrated at a radiation intensity of 0.3 kW/cm2 (405 nm laser) and a scan rate of 5 mm/s for a 1.49 wt % Ag content. This enhanced photothermal characteristic of the nanocomposite, which allows printing at low radiation intensities, is attributed to the efficient coupling of light to the AgNW plasmon modes and the high dispersion of nanowires in the polymer. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47670.
Creep performance of CNT reinforced glass fiber/epoxy composites: Roles of temperature and stress
Authors: Nomula Sai Seetha Ram , Rathore Dinesh Kumar , Ray Bankim Chandra , Prusty Rajesh Kumar
Published: March 2019

Carbon nanotubes (CNTs) have been emerged as a potential nanofiller to reinforce polymeric materials to improve their mechanical properties, like strength and modulus. However, time‐dependent deformation of such materials under a constant load and elevated temperature is a matter of concern for long‐term durability of these materials. The present article primarily demonstrates the effects of creep temperature and stress on the reinforcement efficiency of CNT in a glass fiber/epoxy (GE) composite. Two types of materials were investigated in this study—GE which was used as a control material, as well as CNT embedded GE composite. To elucidate the impact of CNT on the long‐term durability of GE composite, creep tests have been performed at different temperatures (50, 80, and 110 °C) under bending loading. As applied stress has also significant contribution toward the elevated creep deformation of materials, creep tests have also been carried out under different stresses (5, 10, and 40 MPa). The strength of the CNT‐GE composite exhibited 8.7 and 18.3% higher than that of control GE composite under tensile and bending load, respectively. Results suggest CNT reinforcement to be beneficial for low temperature applications, both in terms of creep strain and strain rate. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47674.
IR spectroscopy: Suitable method for determination of curing degree and crosslinking type in melamine–formaldehyde resins
Authors: Weiss Stephanie , Urdl Katharina , Mayer Hermann A. , Zikulnig‐Rusch Edith M. , Kandelbauer Andreas
Published: March 2019

Melamine–formaldehyde (MF) resins are widely used as adhesives and finishing materials in the wood industry. During resin cure, either methylene ether or methylene bridges are formed, leading to the formation of a three‐dimensional resin network. Not only the curing degree, but also the chemical species present in the cured resin determine the quality of the final product. Analytical methods allowing a detailed investigation of network formation are of great benefit to manufacturers. In the present work, resin cure of an MF precondensate is studied at different temperatures (100–200 °C) without considering the initial pH as a factor. Isoconversional kinetic analysis based on exothermal curing enthalpies enables calculation of the crosslinking degree at a given time/temperature regime. A semiquantitative determination of the chemical groups present is performed based on solid‐state nuclear magnetic resonance data. Fourier transform infrared spectroscopy has shown to be a fast and reliable analytical tool with high sensitivity toward functional groups and with great potential for at‐line process control. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47691.
Normal frailty probit model for clustered interval‐censored failure time data
Authors: Wu Haifeng , Wang Lianming
Published: March 2019

Clustered interval‐censored data commonly arise in many studies of biomedical research where the failure time of interest is subject to interval‐censoring and subjects are correlated for being in the same cluster. A new semiparametric frailty probit regression model is proposed to study covariate effects on the failure time by accounting for the intracluster dependence. Under the proposed normal frailty probit model, the marginal distribution of the failure time is a semiparametric probit model, the regression parameters can be interpreted as both the conditional covariate effects given frailty and the marginal covariate effects up to a multiplicative constant, and the intracluster association can be summarized by two nonparametric measures in simple and explicit form. A fully Bayesian estimation approach is developed based on the use of monotone splines for the unknown nondecreasing function and a data augmentation using normal latent variables. The proposed Gibbs sampler is straightforward to implement since all unknowns have standard form in their full conditional distributions. The proposed method performs very well in estimating the regression parameters as well as the intracluster association, and the method is robust to frailty distribution misspecifications as shown in our simulation studies. Two real‐life data sets are analyzed for illustration.
Microwave‐assisted Transition Metal‐catalyzed Coupling Approach to Indazole Diversity
Authors: Oh Yoo Jin , Yum Eul Kgun
Published: March 2019

Diverse mono or biaryl substituents were introduced to indazole moieties under microwave‐assisted palladium‐catalyzed coupling reactions with isomeric bromoindazoles and aryl boronic acids. 1,3‐Disubstituted indazoles were also obtained by CC or CN coupling of monosubstituted indazoles with functionalized terminal alkenes and arylhalides. Facile introduction of diverse substituents to indazoles showed useful synthetic approach for creating indazole compound library to discover biologically active small molecules.
Environmentally sustainable or economically sustainable? The effect of Chinese manufacturing firms' corporate sustainable strategy on their green performances
Authors: Yang Morgan X. , Li Ji , Yu Irina Y. , Zeng Kevin J. , Sun Jian‐Min (James)
Published: March 2019

Environmentally and economically sustainable strategies are predicted to influence the public perception of a firm's green performance in terms of environmental protection as well as corporate social responsibility as a whole. We empirically tested this prediction with the data from 214 Chinese manufacturing firms. Our empirical findings showed that firms' environmentally sustainable strategies are more important compared with the economic ones in shaping firms' green performances. Moreover, we also found a significant moderating effect of employees' education on the relationship between the two sustainable strategies and firms' green performances. We explain the findings and conclude with a discussion of the implications of our findings for academic researchers and practitioners.
Corporate sustainability and institutional shareholders: The pressure of social responsible pension funds on environmental firm practices
Authors: Alda Mercedes
Published: March 2019

This paper analyses the role of social responsible (SR) pension funds as influential institutional shareholders in the corporate sustainability of investee firms. We study the influence of 197 UK SR pension funds on 1,253 firms with 31 environmental, social, and governance (ESG) indicators from 2002 to 2018. According to the indicator nature, we perform logit and ordinary least square (OLS) estimations with panel error correction models to control causality. Our results show that SR pension funds significantly impact on 41.93% of the ESG indicators studied. We find that larger pension‐fund shareholding positively influences on ESG firm performance and encourages proactive behaviour towards environmental practices. Firms with larger pension‐fund shareholding are more likely to use renewable energies and disclose environmental information, increasing the firm transparency towards stakeholders. This study contributes to understand that, besides stakeholders, institutional shareholders (SR pension funds) demand sustainable development and are able to transfer important values for the society and the environment to corporate governance.
TNF‐α mediated MEK–ERK signaling in invasion with putative network involving NF‐κB and STAT‐6: a new perspective in glioma
Authors: Ramaswamy Palaniswamy , Goswami Kalyan , Dalavaikodihalli Nanjaiah Nandakumar , Srinivas Dwarakanath , Prasad Chandrajit
Published: March 2019

Glioblastoma is the most common malignant primary brain tumor with poor prognosis. Invasion involves pro‐inflammatory cytokines and major signaling hubs. Tumor necrosis factor‐α (TNF‐α) acts as a master switch in establishing an intricate link between inflammation and cancer. The present study attempted to explore the possible implication of MAPK extracellular signaling‐regulated kinase kinase (MEK)–extracellular signaling‐regulated kinase (ERK) signaling pathway and expression of nuclear factor‐κB (NF‐κB), signal transducers and activators of transcription‐6 (STAT‐6), ERK, and phosphorylated‐ERK (p‐ERK) signaling proteins in TNF‐α microenvironment. U0126 and PD98059 were used to inhibit the MEK–ERK1/2 pathway. TNF‐α stimulation enhanced invasion in U87MG, U251MG and patient‐derived primary glioma cells, whereas cell viability was not altered. Matrix metalloproteinase‐2 (MMP‐2) activity was increased only in U251MG glioma cells. These data suggest that TNF‐α microenvironment plays an important role in the invasion of U251MG, U87MG, and patient‐derived primary glioma cells, without any cytotoxic effect. The MMP‐2 activity is differentially regulated by TNF‐α stimulation in these cells. TNF‐α stimulation upregulated the protein expression of ERK‐1, ERK‐2 and also increased the level of p‐ERK1/2. TNF‐α stimulation further upregulated the expression of NF‐κB1, STAT‐6 in tandem with Ras–MEK signaling system in U87MG cells, which emphasized the possible involvement of these signaling hubs in the glioma microenvironment. MEK–ERK inhibitors significantly attenuated the invasion of U87MG cells mediated by the TNF‐α stimulation, probably through their inhibitory impact on p‐ERK1/2 and ERK‐2. This study provides the possible rationale of invasion by glioma cells in a TNF‐α‐induced pro‐inflammatory milieu, which involves direct role of MEK–ERK signaling, with possible implication of NF‐κB and STAT‐6.
Wet milling technique applied to deoxynivalenol‐contaminated wheat dry‐milled fractions
Authors: Magallanes López Ana M. , Manthey Frank A. , Simsek Senay
Published: March 2019

Background and objectives

The consumption of wheat contaminated with deoxynivalenol (DON), a highly water‐soluble Fusarium mycotoxin, represents a health threat to animals and humans. Dry milling does not destroy or remove DON from the grain but physically separates the bran and germ from the endosperm. Information is limited concerning the effectiveness of wet milling processes in removing DON from contaminated wheat dry milling fractions (farina/semolina, shorts, bran). The aim of this research was to determine the extent of DON removal from these wheat fractions during wet milling using the Martin process.

Findings

After wet milling farina and semolina containing 2.76–5.07 mg/kg and 3.53–10.39 mg/kg DON, respectively, gluten extracted from hard red spring wheat (HRSW) contained low levels of DON < 0.60 mg/kg, while gluten extracted from durum wheat (DW) contained no detectable DON. The remainder of DON was found in the water‐soluble fraction. After wet milling shorts, DON levels were only detected in the freeze‐dried water‐soluble fraction. After wet milling the bran fraction, DON was found in isolated starch and destarched bran from HRSW and DW; the highest DON concentration was found in the freeze‐dried water‐soluble fraction accounting 83% and 88% in HRSW and DW, respectively.

Conclusions

Results indicated that wet milling was effective in removing DON from the studied dry‐milled fractions.

Significance and novelty

The implementation of the wet milling technique could be useful in reducing or eliminating DON from dry milling products, which would allow them to be used in animal and human food.
Massive subchorionic hematoma (Breus’ mole) presents a variety of ultrasonic appearances: A case report and literature review
Authors: Yanagisawa Fumi , Aoki Shigeru , Odagami Mizuha , Miyagi Etsuko
Published: March 2019

Key Clinical Message

Massive subchorionic hematoma (MSH) presents a variety of ultrasonic appearances. Placentomegaly with fetal growth restriction should be included as one of the differential diagnoses for intraplacental MSH. Care management of MSH requires to be tailored to each individual's responses while taking the NICU's capabilities and the patient's wishes into consideration.
Uranyl–Peroxide Capsule Self‐Assembly in Slow Motion
Authors: Arteaga Ana , Zhang Lei , Hickam Sarah , Dembowski Mateusz , Burns Peter C. , Nyman May
Published: March 2019

Uranyl‐peroxide capsules are the newest family of polyoxometalates. Although discovered 13 years previously with over 70 topologies reported, there is a lack in the fundamental understanding of assembly mechanisms, particularly the role of the alkali counterions. Herein, the reaction pathway and assembly of uranyl peroxide capsules is reported by tracking the conversion from K+ uranyl triperoxide monomer to the K+ uranyl‐peroxide U28 capsule by means of small‐angle X‐ray scattering and Raman spectroscopy. For the first time, the K+ uranyl‐peroxide pentamer face is isolated and structurally characterized, giving credence to the long‐held belief that these geometric faces serve as building blocks to the fully formed capsules. Once isolated and re‐dissolved, the pentamer face undergoes rapid conversion to capsule forms, underlining its high reactivity that challenges its isolation. Calorimetric measurements of the studied species confirms the pentamer lies on the energy landscape between the monomer and capsule.
Sonochemical Formation of Copper/Iron‐Modified Graphene Oxide Nanocomposites for Ketorolac Delivery
Authors: Radziuk Darya , Mikhnavets Lubov , Vorokhta Mykhailo , Matolín Vladimír , Tabulina Ludmila , Labunov Vladimir
Published: March 2019

A feasible sonochemical approach is described for the preparation of copper/iron‐modified graphene oxide nanocomposites through ultrasonication (20 kHz, 18 W cm−2) of an aqueous solution containing copper and iron ion precursors. Unique copper‐, copper/iron‐ and iron‐modified graphene oxide nanocomposites have a submicron size that is smaller than that of pristine GO and a higher surface area enriched with Cu2O, CuO, and Fe2O3 of multiform phases (α‐, β‐, ϵ‐, or γ), FeO(OH), and sulfur‐ or carbon‐containing compounds. These nanocomposites are sonochemically intercalated with the nonsteroidal anti‐inflammatory drug ketorolac, which results in the formation of nanoscale carriers. Ketorolac monotonically disintegrates from these nanoscale carriers in aqueous solution upon adjustment of the pH from 1 to 8. The disintegration of ketorolac proceeds at a slower rate from the copper/iron‐modified graphene oxide at increased pH, but at a faster rate from the iron‐modified graphene oxide under acidic conditions.
Dynamic Methanation of CO2 – Effect of Concentration Forcing
Authors: Kreitz Bjarne , Friedland Jens , Güttel Robert , Wehinger Gregor D. , Turek Thomas
Published: March 2019

Investigating the effect of concentration forcing of the CO2 methanation is not only relevant for power‐to‐gas plants but also for the study of dynamic phenomena of this reaction. In this study a Ni/Al2O3 catalyst is investigated under concentration forcing at industrially relevant conditions. The dynamic experiments allow an evaluation in terms of the reaction rate and enable the study of the reaction mechanism. The experiments show that no methane is formed in the CO2‐rich part of the cycle, whereas a fast hydrogenation of carbonaceous species to methane takes place upon switching to H2.
Recent Advances in Constructing Nitrogen‐Containing Heterocycles via Electrochemical Dehydrogenation
Authors: Ye Zenghui , Zhang Fengzhi
Published: March 2019

In consideration of the importance of nitrogen‐containing heterocycles in both medicinal and material chemistry, herein, we intend to summarize the most recent advances about their synthesis by electrochemical dehydrogenation.
Coconut‐Shell‐Derived Carbon/Carbon Nanotube Composite for Fluoride Adsorption from Aqueous Solution
Authors: Araga Ramya , Kali Suresh , Sharma Chandra S.
Published: March 2019

Devastating effect of fluoride in drinking water on human health is a great concern and defluoridation is essential to make groundwater suitable for drinking. The aim of this study is to evaluate the dissolved fluoride removal efficiency of a novel and low‐cost carbon/carbon nanotube (CNT) composite under batch conditions. CNTs are coated on the coconut‐shell charcoal surface at 450 °C by using plasma‐enhanced chemical vapor deposition. Thereafter, processed charcoal samples are ball milled and used for the fluoride removal from aqueous medium. The amount of fluoride removal is found to be ≈65% of the initial concentration of 4.4 mg L−1 in 3 h contact time at the adsorbent dose of 10 g L−1. The linear forms of three isotherm models (Langmuir, Freundlich, and Temkin) and two kinetic models (pseudo‐first order and pseudo‐second order) are applied to the adsorption data to determine the best fit for equilibrium expression. Isotherm data fit the Langmuir model while the adsorption kinetics is represented by the pseudo‐second‐order kinetic model. The fluoride adsorption process onto prepared carbon/CNT composite occurred spontaneously (ΔG° = −1.656 kJ mol−1) in an endothermic nature (ΔH° = 11.07 kJ mol−1) with increased randomness (ΔS° = 41.69 J mol−1 K−1). To validate the performance further, the as‐prepared adsorbent is successfully used to treat groundwater samples with excess fluoride concentration collected from Nalgonda district, Telangana, India.
Anticancer potential of naturally occurring immunoepigenetic modulators: A promising avenue?
Authors: Schnekenburger Michael , Dicato Mario , Diederich Marc F.
Published: March 2019

The immune system represents the major primary defense line against carcinogenesis and acts by identifying and eradicating nascent transformed cells. A growing body of evidence is indicating that aberrant epigenetic reprogramming plays a key role in tumor immune escape through: 1) impaired efficient recognition of neoplastic cells by the immune system, resulting from a downregulation or loss of the expression of tumor‐associated antigens, human leukocyte antigens, antigen processing and presenting machinery, and costimulatory molecule genes; 2) aberrant expression of immune checkpoint proteins and their ligands; and 3) modification of cytokine profiles and tumor‐associated immune cell populations toward an immunosuppressive state in the tumor microenvironment. Consistent with the inherent reversibility of epigenetic alterations, epigenetic drugs, including DNA methyltransferase and histone deacetylase inhibitors, have the unique potential to favorably modify the tumor microenvironment, restore tumor recognition and stimulate an antitumor immune response. The objective of this review is to highlight selected, naturally occurring epigenetic modulators, namely, butyrate, curcumin, (−)‐epigallocatechin‐3‐gallate, resveratrol, romidepsin, and trichostatin A, with a special focus on their antitumor immune properties.
Image encryption based on a single‐round dictionary and chaotic sequences in cloud computing
Authors: Li Yinghua , Yu He , Song Bin , Chen Jinjun
Published: March 2019

With the increasing popularity of multimedia technology and the prevalence of various smart electronic devices, severe security problems have recently arisen in information and communication systems. The image maintenance can be treated as a typical example of cloud storage outsourcing as images require much more storage space than text documents. An image encryption method with high efficiency is crucial to preserve the privacy of sensitive and critical images in cloud‐edge communications. Compressive sensing (CS) is capable of reconstructing compressible or sparse signals using fewer measurements than traditional methods when the support of the signals is unobtainable in advance. Encryption methods based on CS decrease resources demands during signal acquisition and protect the image data to avoid theft of confidential information by malicious users. Moreover, the CS‐based encryption method can achieve the encryption and the compression of an image simultaneously. Recently, a considerable amount of work using CS theory has been reported. However, most of the existing methods result in recovered images with unsatisfactory quality and employ a massive measurement matrix as the encryption key. This paper proposes an encryption scheme for images on cloud based on a single‐round dictionary and chaotic sequences. Both the experimental and analytical results verify the proposed scheme's effectiveness, high level of security, and substantial image quality improvement after decryption.
Electrochemical Formation of Fe(IV)=O Derived from H2O2 on a Hematite Electrode as an Active Catalytic Site for Selective Hydrocarbon Oxidation Reactions
Authors: Kamiya Kazuhide , Kuwabara Akito , Harada Takashi , Nakanishi Shuji
Published: March 2019

The front cover artwork is provided by the group of Prof. Shuji Nakanishi. The image shows that Fe(lV)=O is generated from H2O2 on a hematite electrode and serve as the active center for selective styrene epoxidation. Read the full text of the Communication at 10.1002/cphc.201801207.
Phase Transformation Behavior and Stability of LiNiO2 Cathode Material for Li‐Ion Batteries Obtained from In Situ Gas Analysis and Operando X‐Ray Diffraction
Authors: de Biasi Lea , Schiele Alexander , Roca‐Ayats Maria , Garcia Grecia , Brezesinski Torsten , Hartmann Pascal , Janek Jürgen
Published: March 2019

Ni‐rich layered oxide cathode materials, in particular the end member LiNiO2, suffer from drawbacks such as high surface reactivity and severe structural changes during de‐/lithiation, leading to accelerated degradation and limiting practical implementation of these otherwise highly promising electrode materials in Li‐ion batteries. Among all known phase transformations occurring in LiNiO2, the one from the H2 phase to the H3 phase at high state of charge is believed to have the most detrimental impact on the material's stability. In this work, the multistep phase transformation process and associated effects are analyzed by galvanostatic cycling, operando X‐ray diffraction, and in situ pressure and gas analysis. The combined results provide thorough insights into the structural changes and how they affect the stability of LiNiO2. During the H2–H3 transformation, the most significant change occurs in the c‐lattice parameter, resulting in large mechanical stress in LiNiO2. As for electrochemical stability, it suffers strongly in the H3 region. Oxygen evolution is observed not only during charge but also during discharge and found to be correlated with the presence of the H2 and H3 phases. Taken together, the experimental data improve the understanding of the degradation processes and the inherent instability of LiNiO2 in Li‐ion cells when operated above around 75 % state of charge.
Fabrication of Efficient and Stable Perovskite Solar Cells in High‐Humidity Environment through Trace‐Doping of Large‐Sized Cations
Authors: Liu Xueping , He Jiang , Wang Pengfei , Liu Yuhao , Xiao Junyan , Ku Zhiliang , Peng Yong , Huang Fuzhi , Cheng Yi‐Bing , Zhong Jie
Published: March 2019

Solution‐processed organic–inorganic lead halide perovskites have shown photovoltaic performance above 23 %, attracting great attention. However, the champion devices require fabrication in a controlled inert/dry atmosphere. The development of highly efficient and stable perovskite solar cells under high‐humidity atmosphere conditions for future commercialization is still challenging, especially for CH3NH3PbI3 (MAPbI3), which is vulnerable to moisture. In this study, a large‐sized tert‐butylammonium [C(CH3)3NH3+] organic cation was incorporated into the MAPbI3 crystalline structure, which could form a more stable 3 D crystalline structure and alleviate the decomposition caused by the humidity. It delivered a power conversion efficiency of 19.3 % upon preparation under a humid environment condition of 50 % relative humidity as well as improved humidity and thermal stability. Our work provides a facile strategy for improving perovskite performance and stability by introducing a new chemical additive for the future application of perovskite solar cells.
Carbonaceous Anodes Derived from Sugarcane Bagasse for Sodium‐Ion Batteries
Authors: Rath Purna Chandra , Patra Jagabandhu , Huang Hao‐Tzu , Bresser Dominic , Wu Tzi‐Yi , Chang Jeng‐Kuei
Published: March 2019

To realize the sustainability of Na‐ion batteries (NIBs) for large‐scale energy storage applications, a resource‐abundant and cost‐effective anode material is required. In this study, sugarcane bagasse (SB), one of the most abundant types of biowaste, is chosen as the carbon precursor to produce a hard carbon (HC) anode for NIBs. SB has a great balance of cellulose, hemicellulose, and lignin, which prevents full graphitization of the pyrolyzed carbon but ensures a sufficiently ordered carbon structure for Na+ transport. Compared with HC derived from waste apples, which are pectin‐rich and have less cellulose than SB, SB‐derived HC (SB‐HC) has fewer defects and a lower oxygen content. SB‐HC thus has a higher first‐cycle sodiation/desodiation coulombic efficiency and better cycling stability. In addition, SB‐HC has a unique flake‐like morphology, which can shorten the Na+ diffusion length, and higher electronic conductivity (owing to more sp2‐hybridized carbon), resulting in superior high‐rate charge–discharge performance to apple‐derived HC. The effects of pyrolysis temperature on the material characteristics and electrochemical properties, evaluated by using chronopotentiometry, cyclic voltammetry, and electrochemical impedance spectroscopy, are systematically investigated for both kinds of HC.
AuPd‐Fe3O4 Nanoparticle‐Catalyzed Synthesis of Furan‐2,5‐dimethylcarboxylate from 5‐Hydroxymethylfurfural under Mild Conditions
Authors: Cho Ahra , Byun Sangmoon , Cho Jin Hee , Kim Byeong Moon
Published: March 2019

Efficient one‐pot oxidative esterification of 5‐hydroxymethylfurfural (HMF) to furan‐2,5‐dimethylcarboxylate (FDMC) was achieved under extremely mild reaction conditions by using AuPd alloy nanoparticles (NPs) supported on Fe3O4. A high yield of FDMC (92 %) was obtained at room temperature under atmospheric O2. The reaction proceeded through the synergistic effects of the AuPd heterobimetallic catalyst system. The most effective molar ratio of noble metal contents for HMF oxidation was 1.00:1.18. If Au‐Fe3O4 NPs were used as the catalyst, selective synthesis of 5‐hydroxymethylfuroic acid methyl ester (HMFE) was achieved. Additionally, the AuPd‐Fe3O4 catalyst could be successfully reused.
Understanding the Oxygen Reduction Reaction Activity and Oxidative Stability of Pt Supported on Nb‐Doped TiO2
Authors: He Cheng , Sankarasubramanian Shrihari , Matanovic Ivana , Atanassov Plamen , Ramani Vijay
Published: March 2019

Commercial fuel cell electrocatalyst degradation results from carbon electrocatalyst support oxidation at high operating potential transients. Guided by density functional theory (DFT) calculations, Nb‐doped TiO2 (NTO) was synthesized, which exhibits a unique combination of high surface area, high electrical conductivity, and high porosity. This catalyst retained 78 % of its initial electrochemically active surface area compared with 57.6 % retained by Pt/C following the DOE/FCCJ protocol for accelerated stability test. Strong metal–support interactions, which were predicted by DFT calculations and confirmed experimentally by X‐ray photoelectron spectroscopy and kinetics measurements, resulted in 21 % higher oxygen reduction reaction mass activity (at 0.9 V vs. reversible hydrogen electrode) on Pt/NTO compared with commercial Pt/C. The ex situ activity and durability of Pt/NTO translated to a fuel cell. The rise in electrode ohmic resistance and non‐electrode concentration overpotential indicate that improving the conductivity of NTO and optimizing the catalyst ink formulation are critical next steps in the development of Pt/NTO‐catalyzed proton exchange membrane fuel cells.
On the performance of two‐user full‐duplex network‐coded cooperation
Authors: Mafra Samuel B. , Fernández Evelio M. G. , Montejo‐Sánchez Samuel , Souza Richard D. , Rayel Ohara K. , Rebelatto João L.
Published: March 2019

In this paper, we propose two schemes based on a full‐duplex network‐coded cooperative communication (FD‐NCC) strategy, namely, full‐duplex dynamic network coding (FD‐DNC) and full‐duplex generalized dynamic network coding (FD‐GDNC). The use of full‐duplex communication aims at improving the spectrum efficiency of a two‐user network where the users cooperatively transmit their independent information to a common destination. In the proposed FD‐NCC schemes, the self‐interference imposed by full‐duplexing is modeled as a fading channel, whose harmful effect can be partially mitigated by interference cancellation techniques. Nevertheless, our results show that, even in the presence of self‐interference, the proposed FD‐NCC schemes can outperform (in terms of outage probability) the equivalent half‐duplex network‐coded cooperative (HD‐NCC) schemes, as well as traditional cooperation techniques. Moreover, the ϵ‐outage capacity, that is, the maximum information rate achieved by the users given a target outage probability, is evaluated. Finally, we examine the use of multiple antennas at the destination node, which increases the advantage of the FD‐NCC (in terms of the diversity‐multiplexing trade‐off and ϵ‐outage capacity).
Provably secure and efficient PUF‐based broadcast authentication schemes for smart grid applications
Authors: Ameri Mohammad Hassan , Delavar Mahshid , Mohajeri Javad
Published: March 2019

Many smart grid applications need broadcast communications. Because of the critical role of the broadcasted messages in these applications, their authentication is very important to prevent message forgery attacks. Smart grid consists of plenty of low‐resource devices such as smart meters or phasor measurement units (PMUs) that are located in physically unprotected environments. Therefore, the storage and computational constraints of these devices as well as their security against physical attacks must be considered in designing broadcast authentication schemes. In this paper, we consider two communication models based on the resources of the broadcasters and receivers and propose a physical unclonable function (PUF)–based broadcast authentication scheme for each of them including Broadcast Authentication with High‐Resource Broadcaster (BA‐HRB) and Broadcast Authentication with Low‐Resource Broadcaster (BA‐LRB). We formally prove that both schemes are unforgeable and memory leakage resilient. Moreover, we analyze the performance of our proposed schemes and compare them with related works. The comparison results demonstrate a significant improvement in the storage and computational overhead of our schemes compared with the related works.
English foreign language teachers' linguistic knowledge, beliefs, and reported practices regarding reading and spelling instruction
Authors: Vaisman Esther Emma , Kahn‐Horwitz Janina
Published: March 2019

The study investigated English as a foreign language (EFL) teachers' knowledge of the linguistic foundations of the English language, teachers' reported classroom practices regarding time allocation to different language teaching and learning activities, and the relationship between these two parameters. An additional goal was to investigate teachers' beliefs regarding various aspects of literacy acquisition. Results indicated low scores for language constructs, especially those related to phonology and orthography. EFL teachers reported dedicating the largest amount of classroom time to vocabulary‐related activities whereas the smallest amounts of time were allotted to teaching phonemic awareness and word reading. Teachers with higher scores on phonological, syllabic, and orthographic knowledge allocated more time to teaching and practicing phonemic awareness, grapheme‐phoneme correspondence, and reading skills. Educational implications include the importance of research based, focused teacher professional training both in content knowledge of basic language constructs and in pedagogical knowledge of EFL literacy acquisition.
Warm, dry winters truncate timing and size distribution of seaward‐migrating salmon across a large, regulated watershed
Authors: Munsch Stuart H. , Greene Correigh M. , Johnson Rachel C. , Satterthwaite William H. , Imaki Hiroo , Brandes Patricia L.
Published: March 2019

Ecologists are pressed to understand how climate constrains the timings of annual biological events (phenology). Climate influences on phenology are likely significant in estuarine watersheds because many watersheds provide seasonal fish nurseries where juvenile presence is synched with favorable conditions. While ecologists have long recognized that estuaries are generally important to juvenile fish, we incompletely understand the specific ecosystem dynamics that contribute to their nursery habitat value, limiting our ability to identify and protect vital habitat components. Here we examined the annual timing of juvenile coldwater fish migrating through a seasonally warm, hydrologically managed watershed. Our goal was to (1) understand how climate constrained the seasonal timing of water conditions necessary for juvenile fish to use nursery habitats and (2) inform management decisions about (a) mitigating climate‐mediated stress on nursery habitat function and (b) conserving heat‐constrained species in warming environments. Cool, wet winters deposited snow and cold water into mountains and reservoirs, which kept the lower watershed adequately cool for juveniles through the spring despite the region approaching its hot, dry summers. For every 1°C waters in April were colder, the juvenile fish population (1) inhabited the watershed 4–7 d longer and (2) entered marine waters, where survival is size selective, at maximum sizes 2.1 mm larger. Climate therefore appeared to constrain the nursery functions of this system by determining seasonal windows of tolerable rearing conditions, and cold water appeared to be a vital ecosystem component that promoted juvenile rearing. Fish in this system inhabit the southernmost extent of their range and already rear during the coolest part of the year, suggesting that a warming climate will truncate rather than shift their annual presence. Our findings are concerning for coldwater diadromous species in general because warming climates may constrain watershed use and diminish viability of life histories (e.g., late springtime rearing) and associated portfolio benefits over the long term. Lower watershed nurseries for coldwater fish in warming climates may be enhanced through allocating coldwater reservoir releases to prolong juvenile rearing periods downstream or restorations that facilitate colder conditions.
Genetic diversity and differentiation in narrow versus widespread taxa ofHelianthemum(Cistaceae) in a hotspot: The role of geographic range, habitat, and reproductive traits
Authors: Martín‐Hernanz Sara , Martínez‐Sánchez Sara , Albaladejo Rafael G. , Lorite Juan , Arroyo Juan , Aparicio Abelardo
Published: March 2019

Unraveling the relationships between ecological, functional traits and genetic diversity of narrow endemic plants provide opportunities for understanding how evolutionary processes operate over local spatial scales and ultimately how diversity is created and maintained. To explore these aspects in Sierra Nevada, the core of the Mediterranean Betic‐Rifean hotspot, we have analyzed nuclearDNAmicrosatellite diversity and a set of biological and environmental factors (physicochemical soil parameters, floral traits, and community composition) in two strictly endemic taxa from dolomite outcrops of Sierra Nevada (Helianthemum pannosumandH. apenninumsubsp. estevei) and two congeneric widespread taxa (H. cinereumsubsp. rotundifoliumandH. apenninumsubsp. apenninum) that further belong to two different lineages (subgenera) ofHelianthemum. We obtained rather unexpected results contrasting with the theory: (a) The narrow endemic taxa showed higher values of genetic diversity as well as higher average values of pollen production per flower and pollen‐to‐ovule ratio than their widespread relatives; and (b) the two taxa of subg.Helianthemum, with larger corollas, approach herkogamy and higher pollen production than the two taxa of subg.Plectolobum, displayed lower genetic diversity and higher values of inbreeding. Altogether, these results disclose how genetic diversity may be affected simultaneously by a large number of intrinsic and extrinsic factors, especially in Pleistocene glacial refugia in mountains where the spatial context harbors a great ecological heterogeneity. On the other hand, differences in mating system and the significant effect of the substrate profile, both being highly diverse in the genusHelianthemum, in the genetic variability illustrate about the importance of these two factors in the diversification and species differentiation of this paradigmatic genus in the Mediterranean and open the field to formulate and test new hypotheses of local adaptation, trait evolution, and habitat diversification.
An integrated model decomposing the components of detection probability and abundance in unmarked populations
Authors: Hostetter Nathan J. , Gardner Beth , Sillett T. Scott , Pollock Kenneth H. , Simons Theodore R.
Published: March 2019

Accurate estimates of population abundance are essential to both theoretical and applied ecology. Rarely are all individuals detected during a survey and abundance models often incorporate some form of imperfect detection. Detection probability, however, consists of three components: probability of presence during a survey, probability of availability given presence, and probability of detection given availability and presence. We develop an integrated model to separate these three detection components and provide abundance estimates for the available, present, and superpopulation of individuals. Our framework integrates several common survey methods for unmarked populations: spatially and temporally replicated counts, distance sampling data, and time‐of‐detection data. Simulations indicated relatively unbiased estimates for detection and availability probabilities. Negative bias in estimated superpopulation abundance was present with three temporally replicated surveys, but greatly reduced with six surveys. In a case study of Island Scrub‐Jays (Aphelocoma insularis), posterior modes for presence, availability, and detection probabilities were 0.78, 0.96, and 0.26, respectively, from 10‐min point counts repeated at 97 sites on three occasions, with noticeable differences among available, present, and superpopulation abundance estimates. This generalizable framework integrates common sampling protocols and provides joint inferences on the components of detection probability, spatial and non‐spatial temporary emigration, and abundance in unmarked populations.
Linking the ball‐and‐cup analogy and ordination trajectories to describe ecosystem stability, resistance, and resilience
Authors: Lamothe Karl A. , Somers Keith M. , Jackson Donald A.
Published: March 2019

The ball‐and‐cup diagram for conceptualizing ecosystem stability, resistance, and resilience is often presented as a ball rolling around within and between two or more cups. This analogy has a long history in ecology and has been used to illustrate ecosystem changes over time where the magnitude of changes required to push the ball from one cup to another represents a regime shift to an alternative state. Another approach for visualizing ecosystem stability, resistance, and resilience involves ordinations of repeated measures of community data or environmental variables and tracking trajectories over time in ordination space. Interestingly, the two approaches have not been linked in a meaningful way. Here, we provide a conceptual link between trajectories of ecological change in ordination space to the ball‐and‐cup analogy and show how distance‐based measures calculated from ordination scores can be used to quantitatively classify and evaluate the relative stability and resilience of ecological systems.
A meta food web for invertebrate species collected in a European grassland
Authors: Hines Jes , Giling Darren P. , Rzanny Michael , Voigt Winfried , Meyer Sebastian T. , Weisser Wolfgang W. , Eisenhauer Nico , Ebeling Anne
Published: March 2019

Patterns of feeding interactions between species are thought to influence the stability of communities and the flux of nutrients and energy through ecosystems. However, surprisingly few well‐resolved food webs allow us to evaluate factors that influence the architecture of species interactions. We constructed a meta food web consisting of 714 invertebrate species collected over 9 years of suction and pitfall sampling campaigns in the Jena Experiment, a long‐term grassland biodiversity experiment located in Jena, Germany. We summarize information on the 51,496 potential trophic links, which were established using information on diet specificity and species traits that typically constrain feeding interactions (trophic group, body size, and vertical stratification). The list of species identities, traits, and link‐derivation rules will be useful not only for tests of plant diversity effects on food web structure within the Jena Experiment, but also for considering consistent construction of food webs from empirical data, and for comparisons of network structure across ecosystems. No copyright or proprietary restrictions are associated with the use of this data set other than citation of this Data Paper.
Decrease in Intramuscular Levels of Phosphatidylethanolamine Bearing Arachidonic Acid During Postmortem Aging Depends on Meat Cuts and Breed
Authors: Yamashita Shinji , Shimada Kenichiro , Sakurai Riho , Yasuda Nohara , Oikawa Nayoko , Kamiyoshihara Reina , Otoki Yurika , Nakagawa Kiyotaka , Miyazawa Teruo , Kinoshita Mikio
Published: March 2019

The intramuscular phospholipid (PL) level is reported to decrease upon postmortem aging of beef, pork, and chicken, and the change affects meat qualities (e.g., myofibrillar fragmentation and drip loss); however, there is still little information on the effect of muscle position and breed on PL compositions. A preliminary study is performed to investigate the effect of intramuscular PL composition on postmortem aging of beef and venison. Loin and round parts of beef and venison are kept at 4 °C for 28 postmortem days to elucidate the maximum effect of meat aging. The arachidonic acid (20:4n‐6) content in PL decreases in round meat during postmortem aging, while the PL 20:4n‐6 content is not affected in loin meat. The PL molecular species analysis reveals that such content reduction is consistent with decreases in phosphatidylethanolamine (PtdEtn) levels, especially that bearing 20:4n‐6. In addition, the content reduction by aging is affected by the meat cuts and the breed. These results suggest that PL variation depends on meat cuts and breed, and the release of 20:4n‐6 from PL has a considerable influence on meat qualities owing to the high reactivity of the polyunsaturated chain. The present results will enable eventual improvement of the taste, smell, and texture of meat during postmortem aging.

Practical Applications: This preliminary study investigates the changes in intramuscular PL composition in beef and venison after postmortem aging. Consequently, PL variation depends on meat cuts and may be induced potentially owing to activity of cytosolic phospholipase A2. Meat properties (e.g., drip, flavor, and taste) are considered as affected by the PL hydrolysis and the 20:4n‐6 release. Therefore, monitoring of variation of PL species might be useful to estimate the condition of meat quality by postmortem aging.

Our preliminary study investigates the changes in intramuscular phospholipid (PL) composition in beef and venison after postmortem aging. Postmortem aging decreases the phospholipid levels in meats. The 20:4n‐6 is released from the meat phospholipid during postmortem aging. The two above‐mentioned are considered due to hydrolyzation of the diacylglycerophospholipids in meats. The hydrolysis of phospholipid may depend on meat cuts and breed.
Pillar[5]arene Based Pseudo[1]rotaxane Operating as Acid/Base‐Controllable Two State Molecular Shuttle
Authors: Zhao Qian , Chen Yuan , Sun Baobao , Qian Cheng , Cheng Ming , Jiang Juli , Lin Chen , Wang Leyong
Published: March 2019

A ethylene glycol bridged pyridine and pillar[5]arene based mechanically selflocked pseudo[1]rotaxane was constructed successfully. The structure and selflocked conformation of pseudo[1]rotaxane were confirmed by 1H, 2D NMR spectrum and HR‐ESI‐MS. It was found that in dilute solution the pseudo[1]rotaxane could be operated as an acid/base‐controllable two state molecular shuttle while In concentrated solution, the pseudo[1]rotaxane existed as a dimer and could be operated from shrinking state to extension state.