bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of Janus Titanium Dioxide Particles via Ultraviolet Irradiation of Pickering Emulsions
Authors: Tan Jasmine Si Jia , Wong Serena Lee Yan , Chen Zhong
Published: January 2020

Pickering emulsions are stabilized by solid particles assembled at an immiscible liquid–liquid interface. In this work, the use of such emulsions to prepare semiconductor Janus particles through UV‐irradiation is explored. Titanium dioxide particles that are prefunctionalized with an alkylsilane or a fluoroalkylsilane are employed to obtain wax‐in‐water emulsion droplets, which consist of the particles partially embedded in the wax core. Different emulsion formation mechanisms are discussed. The emulsified wax droplets are then subjected to ultraviolet irradiation, which photocatalytically degrades the silanes on the exposed portion of the particle surfaces, leading to Janus particles containing partial silane coatings. The particles are finally recovered through dissolution of wax. The Janus particles, which have contrasting wettabilities over their surface, are characterized based on self‐assembly behavior and bulk wetting performance in a compact film, as compared with nonfunctionalized and fully‐functionalized homogeneous particles. Three different types of Janus particles are created and their characters are explained using the concept of the Janus balance. The method has the potential to produce large scale yields in a relatively short time, and can be potentially applied to other semiconductor particles for the generation of Janus particles.
Simple and Ultrafast Fabrication of Invisible Photonic Prints with Reconfigurable Patterns
Authors: Hu Yang , Yang Dongpeng , Huang Shaoming
Published: January 2020

Photonic prints integrated with invisible and reconfigurable patterns are highly desired due to their potential applications in combining anti‐counterfeiting, anti‐photobleaching, and low‐resource consuming. Here, a simple and fast approach is reported to fabricate invisible photonic prints, which are prepared by coating a layer of oleylamine (OAm) on the selective region of hydrophilic photonic paper. Owing to the different wettability and swelling ability between the pattern and background regions, the pattern of the as‐prepared sample is invisible (Δλ = 0) at normal conditions, while it can be revealed with a large color contrast (Δλ = 140 nm) in the presence of water with a very short time (≈2 s). The hiding–showing transition is fully reversible and the sample shows good performance in long lasting stability. With elaborate mask, the presented method is also capable of preparing microscopic invisible photonic print with high resolution. Moreover, the pattern of the invisible photonic print can be reconfigured repeatedly through the erasing and reconstructing process, which works well in macro/microscopic scale. The combination of invisible and reconfigurable properties as well as the invisible photonic prints with macro and microscopic patterns will facilitate their practical applications such as anti‐counterfeiting, message storage, and display.
Polymer Nanofibers Exhibiting Remarkable Activity in Driving the Living Polymerization under Visible Light and Reusability
Authors: Xia Lei , Cheng Bo‐Fei , Zeng Tian‐You , Nie Xuan , Chen Guang , Zhang Ze , Zhang Wen‐Jian , Hong Chun‐Yan , You Ye‐Zi
Published: January 2020

Visible light‐driving syntheses have emerged as a powerful tool for organic synthesis and for the preparation of macromolecules under mild and environmentally benign conditions. However, precious but nonreusable photosensitizers or photocatalysts are often required to activate the reaction, limiting its practicality. Here, it is reported that poly(1,4‐diphenylbutadiyne) (PDPB) nanofibers exhibit remarkable activity in driving the living free radical polymerization under visible light. Moreover, PDPB nanofibers are very stable under irradiation of visible light and can be reused without appreciable loss of activity even after repeated cycling. The nanofiber will be a promising photocatalyst with excellent reusability and stability for the reactions driven by visible light.
High‐Electric‐Field‐Induced Phase Transition and Electrical Breakdown of MoTe2
Authors: Kim Changsik , Issarapanacheewin Sudarat , Moon Inyong , Lee Kwang Young , Ra Changho , Lee Sungwon , Yang Zheng , Yoo Won Jong
Published: January 2020

2D molybdenum ditelluride (MoTe2) has recently received significant attention due to its unique phase transition and ambipolar behavior as well as thickness‐dependent bandgap. The phase transition and electrical breakdown of various thickness MoTe2 field‐effect transistors observed under high electric fields are addressed. Interestingly, the MoTe2 exhibits phase transition from a semiconducting 2H phase to a metallic 1T′ almost simultaneously with electrical breakdown, and this is confirmed by a Raman peak of 1T′‐MoTe2 at 125 cm−1. Using Raman mapping results of MoTe2 FETs obtained after the breakdown, it is revealed that the phase transition is initiated from the metal contacting electrode regions of source and drain. All the Raman peaks of MoTe2 shifted to low frequency with increasing drain voltage. Based on the Raman peak shifts, the temperature change in the MoTe2 FETs while device operation is in progress is estimated. The maximum temperature and dissipated power of a tri‐layer MoTe2 device are found to reach 495 K and 5.85 mW, respectively, at an electric field of 6.5 V µm−1. This research provides guidelines for circuit design toward the application of 2D semiconductor devices, related to the energy dissipation and electrical breakdown unique to 2D phase transitional materials.
Malleability and Pliability of Silk‐Derived Electrodes for Efficient Deformable Perovskite Solar Cells
Authors: Ma Peipei , Lou Yanhui , Cong Shan , Lu Zheng , Zhu Kaiping , Zhao Jie , Zou Guifu
Published: January 2020

For the fabrication of deformable electronic devices, electrodes that are robust against repeated bending, twisting, stretching, folding, reversible plasticizing, and that maintain electrical conductivity, and so on, are required. Malleable and pliable silk‐derived electrodes are fabricated to enable the shape deformation of perovskite solar cells. Moisture‐driven silk‐derived electrodes show reversible plasticization with malleability and pliability, realizing diverse deformation from simple operations (including bending, folding, stretching, etc.) to complicated structures (including flower, bowknot, and paper crane). It is worth noting that the silk‐derived electrodes maintain electrical conductivity (15.8 Ω sq−1) compared to their initial value (15 Ω sq−1) even after suffering from reversible mechanical plasticization of complicated structures. Deformable perovskite solar cells are fabricated with the silk‐derived electrodes and achieve a power conversion efficiency of 10.40%. The devices maintain 92% of the initial efficiency after 1000 bends at a curvature radius of 2.5 mm. The power does not decline at 50% strain and keeps more than 60% of the initial value after stretching for 50 cycles. Malleability and pliability of silk‐derived electrodes benefit the realization of stretchable perovskite solar cells and deformable electronic devices.
Cross‐Linking between Sodalite Nanoparticles and Graphene Oxide in Composite Membranes to Trigger High Gas Permeance, Selectivity, and Stability in Hydrogen Separation
Authors: Guo Hailing , Kong Guodong , Yang Ge , Pang Jia , Kang Zixi , Feng Shou , Zhao Lei , Fan Lili , Zhu Liangkui , Vicente Aurélie , Peng Peng , Yan Zifeng , Sun Daofeng , Mintova Svetlana
Published: January 2020

Thin membranes (900 nm) were prepared by direct transformation of infiltrated amorphous precursor nanoparticles, impregnated in a graphene oxide (GO) matrix, into hydroxy sodalite (SOD) nanocrystals. The amorphous precursor particles rich in silanols (Si−OH) enhanced the interactions with the GO, thus leading to the formation of highly adhesive and stable SOD/GO membranes via strong bonding. The cross‐linking of SOD nanoparticles with the GO in the membranes promoted both the high gas permeance and enhanced selectivity towards H2 from a mixture containing CO2 and H2O. The SOD/GO membranes are moisture resistance and exhibit steady separation performance (H2 permeance of about 4900 GPU and H2/CO2 selectivity of 56, with no degradation in performance during the test of 50 h) at high temperature (200 °C) under water vapor (4 mol %).
Synthesis of Electron‐Deficient Corona[5]arenes and Their Selective Complexation with Dihydrogen Phosphate: Cooperative Effects of Anion–π Interactions
Authors: Guo Shen‐Yi , Guo Qing‐Hui , Tong Shuo , Wang Mei‐Xiang
Published: January 2020

Reported here are the syntheses, conformational structures, electrochemical properties, and noncovalent anion binding of corona[5]arenes. A (3+2) fragment coupling reaction proceeded efficiently under mild reaction conditions to produce a number of novel heteroatom‐ and methylene‐bridged corona[3]arene[2]tetrazine macrocycles. Selective oxidation of the sulfur atom between two phenylene rings afforded sulfoxide‐ and sulfone‐linked corona[5]arenes in good yields. All corona[5]arenes synthesized adopted similar 1,2,4‐alternate conformational structures, forming pentagonal cavities. The cavity sizes and the electronic properties such as redox potentials, were measured with CV and DPV, and were influenced by the different bridging units. As electron‐deficient macrocycles, the acquired corona[3]arene[2]tetrazines served as highly selective hosts, forming complexes with the hydrogen‐bonded dimer of dihydrogen phosphate through cooperative anion–π interactions.
Enhancing Multicomponent Metal–Organic Frameworks for Low Pressure Liquid Organic Hydrogen Carrier Separations
Authors: Macreadie Lauren K. , Babarao Ravichandar , Setter Caitlin J. , Lee Seok J. , Qazvini Omid T. , Seeber Aaron J. , Tsanaktsidis John , Telfer Shane G. , Batten Stuart R. , Hill Matthew R.
Published: January 2020

The resurgence of interest in the hydrogen economy could hinge on the distribution of hydrogen in a safe and efficient manner. Whilst great progress has been made with cryogenic hydrogen storage or liquefied ammonia, liquid organic hydrogen carriers (LOHCs) remain attractive due to their lack of need for cryogenic temperatures or high pressures, most commonly a cycle between methylcyclohexane and toluene. Oxidation of methylcyclohexane to release hydrogen will be more efficient if the equilibrium limitations can be removed by separating the mixture. This report describes a family of six ternary and quaternary multicomponent metal–organic frameworks (MOFs) that contain the three‐dimensional cubane‐1,4‐dicarboxylate (cdc) ligand. Of these MOFs, the most promising is a quaternary MOF (CUB‐30), comprising cdc, 4,4′‐biphenyldicarboxylate (bpdc) and tritopic truxene linkers. Contrary to conventional wisdom that adsorptive interactions with larger, hydrocarbon guests are dominated by π–π interactions, here we report that contoured aliphatic pore environments can exhibit high selectivity and capacity for LOHC separations at low pressures. This is the first time, to the best of our knowledge, where selective adsorption for cyclohexane over benzene is witnessed, underlining the unique adsorptive behavior afforded by the unconventional cubane moiety.
Early Transition Metal Catalysis for Olefin–Polar Monomer Copolymerization
Authors: Chen Jiazhen , Gao Yanshan , Marks Tobin J.
Published: January 2020

Introducing polar functional groups into widely used polyolefins can enhance polymer surface, rheological, mixing, and other properties, potentially upgrading polyolefins for advanced, value‐added applications. The metal catalyst‐mediated copolymerization of non‐polar olefins with polar comonomers represents the seemingly most straightforward, atom‐ and energy‐efficient approach for synthesizing polar functionalized polyolefins. However, electrophilic early transition metal (groups 3 and 4)‐catalyzed processes which have achieved remarkable success in conventional olefin polymerizations, encounter severe limitations here, largely associated with the Lewis basicity of the polar co‐monomers. In recent years, however, new catalytic systems have been developed and successful strategies have emerged. In this Minireview, we summarize the recent progress in early transition metal polymerization catalyst development, categorized by the catalytic metal complex and polar comonomer identity. Furthermore, we discuss advances in the mechanistic understanding of these polymerizations, focusing on critical challenges and strategies that mitigate them.
Univariate and multivariate strategies for the rheological tests evaluation: Influence of additives in composite materials
Authors: Vita Silvia , Ricotti Rico , Malegori Cristina , Oliveri Paolo , Castellano Maila , Vicini Silvia
Published: January 2020

Filler formulations are complex systems, characterized by a high number of components with different nature, as resins, extenders, additives. One of the main properties of a two‐component epoxy filler used for yacht application is the rheology. Thus, rheological additives are studied in both components after different times from the production. Rheological analysis produces a very large amount of information so statistical methods are useful to elaborate the data. In this study, a univariate approach (ANOVA) and a multivariate data processing, namely, principal component analysis after low‐level data fusion are carried out. It is shown that the multivariate approach provides the maximum useful information on the system. No differences are highlighted in the rheological behavior for the epoxy component, by using different additives while, for the polyamide component, the best rheological additive among the tested is the one that has a polyamide nature, being a polar system as itself.
Study on flame retardancy of APP/PEPA/MoO3synergism in vinyl ester resins
Authors: Zeng Gaofeng , Zhang Weiwei , Zhang Xin , Zhang Wenchao , Du Jianxin , He Jiyu , Yang Rongjie
Published: January 2020

A range of flame retardant vinyl ester resins (VERs) samples have been produced containing different contents of PEPA (1‐oxo‐4‐hydroxymethyl‐2,6,7‐trioxa‐l‐phosphabicyclo[2.2.2]octane), APP (ammonium polyphosphate), and MoO3(molybdenum trioxide). By investigating the flame retardancy of VER samples such as limiting oxygen index and UL‐94, the synergistic flame retardance of APP, PEPA, and MoO3 has been revealed. The cone calorimeter is an instrument that measures the combustion data of samples. In the VER composites on fire, the synergistic smoke suppression effect of the APP, PEPA, and MoO3was detected. The gas and condensed phase of VER composites with APP, PEPA, and MoO3were tested by the thermogravimetric analysis (TGA)–Fourier transform infrared spectroscopy (FTIR) and FTIR. The char residues of samples have been studied at length by scanning electron microscopy and FTIR. The results show that the presence of MoO3 can promote the formation of PO and PO structures.
Moderate prenatal ethanol exposure in the rat promotes kidney cell apoptosis, nephron deficits, and sex‐specific kidney dysfunction in adult offspring
Authors: Akison Lisa K. , Probyn Megan E. , Gray Stephen P. , Cullen‐McEwen Louise A. , Tep Karrona , Steane Sarah E. , Gobe Glenda C. , Wlodek Mary E. , Bertram John F. , Moritz Karen M.
Published: January 2020

Alcohol during pregnancy can impair fetal development and result in offspring with neurodevelopmental deficits. Less is known about how low to moderate alcohol exposure can affect other organs, such as the kidney. Here, the effects of moderate ethanol exposure throughout pregnancy on kidney development were examined using a rat model. Rats were fed a liquid diet containing 6% ethanol (vol/vol) or control (0% ethanol) throughout pregnancy. Kidneys were collected at embryonic day (E) 20 or postnatal day (PN) 30 and total glomerular (nephron) number determined using unbiased stereology. Kidney function was examined in offspring at 8 and 19 months. At E20, fetuses exposed to ethanol had fewer nephrons with increased apoptosis. Alcohol exposure caused kidney dysregulation of pro‐ (Bax) and anti‐ (Bcl‐2) apoptotic factors, and reduced expression of the cell proliferation marker, Ki67. Prenatal alcohol decreased expression of Gdnf and Tgfb1, important regulators of branching morphogenesis, in male fetuses. At PN30, kidney volume and nephron number were lower in offspring exposed to prenatal alcohol. Urine flow and osmolality were normal in offspring exposed to alcohol however sodium excretion tended to be lower in females prenatally exposed to alcohol. Findings suggest exposure to moderate levels of alcohol during pregnancy results in impaired kidney development and leads to a permanent nephron deficit. Although the impact on adult kidney function was relatively minor, these data highlight that even at moderate levels, alcohol consumption during pregnancy can have deleterious long‐term outcomes and should be avoided.
Unique Thia‐Baeyer–Villiger‐Type Oxidation of Dibenzothiophene Sulfoxides Derivatives
Authors: Shi Wenjun , Zhou Xinrui , Kong Yang , Li Jie , Markó István E.
Published: January 2020

The present research has demonstrated that selective C−S bond cleavages of dibenzothiophene and its derivatives are feasible by thia‐Baeyer–Villiger type oxidation, i. e. the oxygen insertion process within a sulfoxide‐carbon linkage, in the presence of porphyrin iron (III) and by ultraviolet irradiation originating from sunlight, high pressure Hg‐lamp or residentially germicidal ultraviolet lamp under very mild conditions. This reaction with tert‐butylhydroperoxide at 30.0 °C leads to dibenzo[1,2]oxathiin‐6‐oxide (PBS) in 83.2 % isolated yield or its hydrated products, 2‐(2‐hydroxyphenyl)‐benzenesulfinic derivatives (HPBS) in near 100 % yield based HPLC data. PBS and HPBS are a type of biological products detected on the C−S bond cleavage step through various oxidative biodesulfurization (OBDS) pathways, and are useful synthetic intermediates and fine chemicals. These observations may contribute on understanding delicately molecular aspect of OBDS in the photosynthesis system, expanding the C‐S cleavage chemistry of S‐heterocyclic compounds and approaching toward biomemic desulfurization with respect to converting sulfur contaminants to chemically beneficial blocks as needed and performing under the ambient conditions.
A highly sensitive and selective detection of picric acid using fluorescent sulfur‐doped graphene quantum dots
Authors: Kadian Sachin , Manik Gaurav
Published: January 2020

The development of an analytical probe to monitor highly mutagenic picric acid (PA) carries enormous significance for the environment and for health. A novel, simple and rapid fluorescence analytical assay using sulfur‐doped graphene quantum dots (SGQDs) was designed for the highly sensitive and selective detection of PA. SGQDs were synthesized via simple pyrolysis of 3‐mercaptopropionic acid and citric acid and characterized using advanced analytical techniques. Fluorescence intensity (FI) of SGQDs was markedly quenched by addition of PA, attributed to the inner filter effect and dominating static quenching mechanism between the two, in addition to a significant colour change. The calibration curve of the proposed assay exhibited a favourable linearity between quenched FI and PA concentration over the 0.1–100 μΜ range with a lowest detection limit of 0.093 μΜ and a correlation coefficient of 0.9967. The analytical assay was investigated for detection of trace amounts of PA in pond and rain water samples and showed great potential for practical applications with both acceptable recovery (98.0–100.8%) and relative standard deviation (1.24–4.67%). Analytical performance of the assay in terms of its detection limit, linearity range, and recovery exhibited reasonable superiority over previously reported methods, thereby holding enormous promise as a simple, sensitive, and selective method for detection of PA.
Uric acid is associated with cognitive impairment in the elderly patients receiving maintenance hemodialysis—A two‐center study
Authors: Zhang Jing , Tang Lijuan , Hu Jun , Wang Yuwei , Xu Yuzhen
Published: January 2020

Background

Elevated serum uric acid (SUA) has been associated with vascular cognitive impairment (CI) in the elderly. However, its relationship with cognitive function in the elderly patients receiving maintenance hemodialysis (MHD) has not yet been elucidated.

Objective

The cognitive impairment is prevalent in MHD patients. Various insults may contribute to cognitive impairment in patients with MHD. The aim of this study was to investigate the relationship between SUA and CI in the elderly patients receiving MHD.

Methods

A total of 180 elderly MHD subjects from two hospitals were enrolled in our study. Cognitive function domains were evaluated by MMSE at the beginning of the trial. Demographic and clinical characteristics were collected and recorded.

Results

The subjects were stratified into quartiles according to SUA level. Demographic and clinical characteristics such as age, gender, smoking habit, education year, blood pressure (BP), hemoglobin, albumin, blood glucose (BG), total cholesterol (TC), triglycerides (TG), high‐density lipoprotein cholesterol (HDL), low‐density lipoprotein cholesterol (LDL), blood urea nitrogen (BUN), and serum creatinine (Scr) did not differ dramatically among groups (p > .05). The Q1 group showed the highest MMSE scores, and the Q4 group showed the lowest MMSE sores (p < .05). There was a negative correlation between SUA and MMSE scores (r = −.307, p = .014), and this correlation was independent of demographic and clinical characteristics.

Conclusions

Elevated SUA maybe contributes to CI in the elderly MHD patients. SUA level is independent risk for the CI in the elderly MHD patients.
Using time‐lagged panel data analysis to study mechanisms of change in psychotherapy research: Methodological recommendations
Authors: Falkenström Fredrik , Solomonov Nili , Rubel Julian
Published: January 2020

The introduction of novel methodologies in the past decade has advanced research on mechanisms of change in observational studies. Time‐lagged panel models allow us to track session‐by‐session changes and focus on within‐patient associations between predictors and outcomes. This shift is crucial as change in mechanisms inherently takes place at a within‐patient level. These models also enable preliminary casual inferences, which can guide the development of effective personalised interventions that target mechanisms of change, used at specific treatment phases for optimal effect. Given their complexity, panel models need to be implemented with caution, as different modelling choices can significantly affect results and reduce replicability. We outline three central methodological recommendations for use of time‐lagged panel analysis to study mechanisms of change: (a) taking patient‐specific effects into account, separating out stable between‐person differences from within‐person fluctuations over time; (b) properly controlling for autoregressive effects; and (c) considering long‐term time trends. We demonstrate these recommendations in an applied example examining the session‐by‐session alliance–outcome association in a naturalistic psychotherapy study. We present limitations of time‐lagged panel analysis and future directions.
Pr2O3 Supported Nano‐layered Ruthenium Catalyzed Acceptorless Dehydrogenative Synthesis of 2‐Substituted Quinolines and 1,8‐Naphthyridines from 2‐Aminoaryl Alcohols and Ketones
Authors: Chaudhari Chandan , Sato Katsutoshi , Ogura Yuta , Miayahara Shin‐Ichiro , Nagaoka Katsutoshi
Published: January 2020

Pr2O3 supported Ru nanolayers and Ru nanoparticles catalysts were examined for the synthesis of quinolines. The Ru nanolayer was most active catalyst and showed a broad substrate scope. Structure‐activity relationship demonstrated that the metallic state and morphology of Ru as well as the basic site of Pr2O3 were indispensable factors of this catalytic system.
Polymer Film Heat Transfer Surfaces in Seawater Desalination: Fouling Layer Formation and Technology
Authors: Kiepfer Hendrik , Omar Waid , Schröder Timo , Bart Hans-Jörg
Published: January 2020

The emerging polyether ether ketone (PEEK) films were evaluated as future heat exchanger materials in seawater thermal desalination processes. Fouling resistance curves were measured in a pilot plant for pure PEEK films, talcum‐filled PEEK films, and stainless‐steel films with artificial seawater, showing that pure PEEK films have the advantage of weaker forces of adhesion or cohesion between the scaling materials and the film surface. Increasing the flow rate from 18 to 24 L min−1 results in decreases of both the fouling rate and the asymptotic values. This was attributed to the lower polarity of 10.4 %, the lower arithmetic average roughness of 0.06 μm, and the homogeneous topography of the PEEK film. This polymer film is adaptable to in situ cleaning in thermal seawater desalination processes.
Analysis of organophosphate pesticides in surface water—Comparison of method optimization approaches
Authors: Habedank Friederike , Feldhusen Frerk , Schulz‐Bull Detlef , Kanwischer Marion
Published: January 2020

A multiresidue method optimization was conducted using the design of experiment approach. Out of 43 tested organophosphate compounds, 27 could be validated in surface water, yielding limits of detection of 0.6 to 2.5 ng L
by dispersive liquid‐liquid micro‐extraction and subsequent liquid chromatography‐tandem quadrupole mass spectrometry (LC‐MSMS) detection. For the optimization of the sample preparation, the factors sonication time, sample volume, binary extraction ratio, and addition of salt have been investigated by the Taguchi design of experiment approach. One hundred fifty milliliters sample were extracted for 1 minute with 400 
 L acetone and 800 
 L tetrachloroethene (TCE) three times subsequently. No salts were added. Combined extracts were reconstituted in 65 
 L methanol, ready for analysis.

The design of experiment approach for method optimization is discussed thoroughly. The comparison to one factor at a time approach focuses on overall experimental expenditure, factor space coverage, acquired information regarding factor interactions, and statistical confirmation of results. Based on two similar analytical methods, it is illustrated that fewer but statistically derived experiments yield more information about the overall system enabling enhanced evaluation of experiment results.
Engineering of Laccase CueO for Improved Electron Transfer in Bioelectrocatalysis by Semi‐Rational Design
Authors: Zhang Lingling , Cui Haiyang , Dhoke Gaurao V. , Zou Zhi , Sauer Daniel F. , Davari Mehdi D. , Schwaneberg Ulrich
Published: January 2020

Copper efflux oxidase (CueO) from Escherichia coli is a special bacterial laccase due to its fifth copper binding site. Herein, it is discovered that the fifth Cu occupancy plays a crucial and favorable role of electron relay in bioelectrocatalytic oxygen reduction. By substituting the residues at the four coordinated positions of the fifth Cu, 11 beneficial variants are identified with ≥2.5‐fold increased currents at −250 mV (up to 6.13 mA cm−2). Detailed electrocatalytic characterization suggests the microenvironment of the fifth Cu binding site governs the electrocatalytic current of CueO. Additionally, further electron transfer analysis assisted by molecular dynamics (MD) simulation demonstrates that an increase in localized structural stability and a decrease of distance between the fifth Cu and the T1 Cu are two main factors contributing to the improved kinetics of CueO variants. It may guide a novel way to tailor laccases and perhaps other oxidoreductases for bioelectrocatalytic applications.
Modulating the Electronic and Solid‐State Structure of Organic Semiconductors by Site‐Specific Substitution: The Case of Tetrafluoropentacenes
Authors: Geiger Thomas , Schundelmeier Simon , Hummel Thorsten , Ströbele Markus , Leis Wolfgang , Seitz Michael , Zeiser Clemens , Moretti Luca , Maiuri Margherita , Cerullo Giulio , Broch Katharina , Vahland Jörn , Leo Karl , Maichle‐Mössmer Cäcilia , Speiser Bernd , Bettinger Holger F.
Published: January 2020

The properties as well as solid‐state structures, singlet fission, and organic field‐effect transistor (OFET) performance of three tetrafluoropentacenes (1,4,8,11: 10, 1,4,9,10: 11, 2,3,9,10: 12) are compared herein. The novel compounds 10 and 11 were synthesized in high purity from the corresponding 6,13‐etheno‐bridged precursors by reaction with dimethyl 1,2,4,5‐tetrazine‐3,6‐dicarboxylate at elevated temperatures. Although most of the molecular properties of the compounds are similar, their chemical reactivity and crystal structures differ considerably. Isomer 10 undergoes the orbital symmetry forbidden thermal [4+4] dimerization, whereas 11 and 12 are much less reactive. The isomers 11 and 12 crystallize in a herringbone motif, but 10 prefers π–π stacking. Although the energy of the first electric dipole‐allowed optical transition varies only within 370 cm−1 (0.05 eV) for the neutral compounds, this amounts to roughly 1600 cm−1 (0.20 eV) for radical cations and 1300 cm−1 (0.16 eV) for dications. Transient spectroscopy of films of 11 and 12 reveals singlet‐fission time constants (91±11, 73±3 fs, respectively) that are shorter than for pentacene (112±9 fs). OFET devices constructed from 11 and 12 show close to ideal thin‐film transistor (TFT) characteristics with electron mobilities of 2×10−3 and 6×10−2 cm2 V−1 s−1, respectively.
Peritheliomatous pattern: A diagnostic clue for diagnosing metastatic melanoma in cytology
Authors: Upadhyay Baskota Swikrity , Monaco Sara E. , Xing Juan , Pantanowitz Liron
Published: January 2020

Background

A peritheliomatous pattern (PP) in tumors is characterized by a sheath of viable tumor cells closely surrounding a central blood vessel. In the authors' cytology practice, such a PP has been recognized in several metastatic melanoma specimens. The aim of this study was to evaluate the frequency of a PP in cytology samples of melanoma in comparison with other tumors.

Methods

Eighty archival fine‐needle aspiration (FNA) cases of metastatic melanoma were compared with 65 control cases (35 poorly differentiated/metastatic carcinomas, 15 lymphomas, and 15 recurrent/metastatic/high‐grade sarcomas). Cytologic findings were correlated with corresponding histologic specimens, which were available for 44 cases (55%) in the melanoma group and for 23 cases (35.38%) in the control group. All slides were examined for a PP and were semiquantitatively graded for comparison.

Results

A PP was present in 51.3% of the cytologic preparations (n = 41) among the melanoma group cases, whereas in the control group, a PP was present in only 3.1% of the cases (n = 2). A PP was present in 65.9% of melanomas with available histologic sections (n = 29) and in 8.7% of tissue samples from the control group (n = 2). A PP was seen more often in cell blocks than direct smear preparations (51.3% vs 40.0%) from patients with melanoma.

Conclusions

The presence of a characteristic PP can be helpful in diagnosing melanoma in FNA samples because it was present in almost half of the metastatic melanoma cases in this study and was rarely present in other tumor types. A PP is easier to recognize and more often presents in cell blocks than aspirate smears. Ancillary studies such as immunohistochemistry are helpful for excluding other entities that may exhibit a PP.
Sunlight‐Driven Synthesis of 1,2,4‐Thiadiazoles via Oxidative Construction of a Nitrogen‐Sulfur Bond Catalyzed by a Reusable Covalent Organic Framework
Authors: Yuan Jiangpei , Xia Qiangqiang , Zhu Weiwei , Wu Cunluo , Wang Bingxin , Liu Baoying , Yang Xiaobo , Xu Yuanqing , Xu Hao
Published: January 2020

Employing a two‐dimensional covalent organic framework as the reusable solar photosensitizer, the sunlight‐driven aerobic oxidative construction of a nitrogen‐sulfur bond has been achieved. 3,5‐Disubstituted 1,2,4‐thiadiazoles are smoothly prepared in water by using this procedure. Furthermore, a radical mechanism with a sunlight‐promoted single electron transfer (SET) process is proposed for this transformation.
Low power and area efficient error tolerant adder for image processing application
Authors: Priyadharshni M , Kumaravel Sundaram
Published: January 2020

Approximate computing‐based arithmetic units are oriented towards reduction in power, delay, and area. Intrinsic error tolerance capability of emerging application domains, like multimedia, Internet of Things (IoT), and image processing provides better opportunities for optimization of approximate arithmetic units. In this paper, a novel 1‐bit imprecise full adder (IFA) is proposed with less gate count. Also, two versions of 16‐bit error tolerant adders (ETAs), namely a low power and area efficient error tolerant adder (LETA) and improved low power and area efficient error tolerant adder (ILETA), are proposed. In these proposed ETAs, the most significant bit (MSB) segments are realized in same approach, whereas the least significant bit (LSB) segment of LETA and ILETA are realized using an existing modified full adder (MFA) and proposed IFAs, respectively. The proposed and existing ETA adders are implemented using a Verilog hardware description language (HDL) and synthesized in a Synopsys electronic design automation (EDA) Tool using Taiwan Semiconductor Manufacturing Company (TSMC) 65nm technology. The proposed (ILETA, LETA) adders exhibit (55%, 50%) reduction in power consumption and achieve significant reduction in area (68%, 61%). Further, in this work, a new performance metric namely power and error product (PEP) is proposed in order to evaluate the approximate adders in terms of power and error metrics. It is found that the proposed ILETA achieves a low PEP of 1.05

compared with other ETAs. To study the efficacy of the proposed ETA adders in image processing application, an image blending algorithm is implemented and simulated using MATLAB. From simulation results, it is observed that the proposed ETA adders exhibit a high peak signal‐to‐noise ratio (PSNR).
Screening and confirmatory analysis of recombinant human erythropoietin for racing camels' doping control
Authors: Delcourt Vivian , Garcia Patrice , Chabot Benjamin , Loup Benoit , Remy Pierre , Popot Marie‐Agnès , Bailly‐Chouriberry Ludovic
Published: January 2020

Recombinant human erythropoietin (rHuEPO) belongs to the therapeutic class of erythropoiesis stimulating agents (ESAs) due to its implication in the creation pathway of red blood cells and thus enhancement of oxygenation. Because of this bioactivity, rHuEPO has been considered as a major doping agent in sports competitions for decades. Over the years, doping control laboratories designed several analytical strategies applied to human and animal samples to highlight any misuse. Even though multiple analytical approaches have been reported, none has yet been dedicated to racing camels. Here, we describe an analytical strategy to test camel plasma samples at screening using an ELISA assay and a targeted nano‐liquid chromatography–high‐resolution tandem mass spectrometry for confirmatory analysis. The method was validated and has been successfully applied to post‐race samples, allowing the detection of a positive case of rHuEPO administration.
Overlooked side effects of organic farming inputs attract soil insect crop pests
Authors: Nyamwasa Innocent , Li Kebin , Zhang Shuai , Yin Jiao , Li Xiaofeng , Liu Jie , Li Ertao , Sun Xiulian
Published: January 2020

Organic farming has been praised for many sound reasons, but there are some negative effects of organic practices. Research on the interactions between soil insect pests and organic farming practices is still scarce, although such interactions might sometimes lead to severe crop damage. Here, we explore the influences of organic farming inputs and key host crops on the oviposition behavior of soil insect pests likely to infest crops. We also shed light on the factors driving this behavior and analyze 4 yr of data from an on‐farm investigation. Our study offers clear support to the idea that decomposing organic matter and legume crops affect oviposition behavior and provides evidence that butyric acid and 1‐hexanol are major attractants. The results suggest that poor management or returning decomposing organic matter to the field is risky. The silver lining, however, is that oviposition behavior can be disrupted by the identified key attractants to benefit crop protection.
Connectivity but not recruitment: Response of the fish community to a large‐scale flood on a heavily regulated floodplain
Authors: Cruz Derrick O. , Kingsford Richard T. , Suthers Iain M. , Rayner Thomas S. , Smith James A. , Arthington Angela H.
Published: January 2020

Recent environmental flow management in the Murray–Darling basin, south‐eastern Australia, has centred on restoring natural flooding regimes to meet ecological requirements, including the promotion of native fish recruitment, despite uncertainty about the effectiveness of managed environmental flooding. This study investigated recruitment responses of small‐bodied native and non‐native fish species to a large natural flood, supported by managed environmental flows in the Macquarie Marshes of the Murray–Darling basin. We surveyed the fish community within the heavily regulated, dryland floodplain system of the marshes, the year after breaking of the Millennium drought (2002–2009). During the spring–summer of 2010, the Macquarie Marshes experienced a one‐in‐10‐year flood, sustained by two environmental flow allocations, flooding 174,000 ha of floodplain. Five native species were collected across the nine study sites. Two non‐native species were particularly abundant during the flood, outnumbering the five native species in a ratio of 32:1, with Gambusia holbrooki the most abundant species, comprising 87% of all native and non‐native individuals captured. There was no marked effect of flood stage on the total abundance of small‐bodied native or non‐native fishes, but the composition of the fish community varied between surveys of the rising and falling phases of the flood. We did not capture any larval or post‐larval fish despite using a variety of suitable sampling methods. The lack of larvae in the Macquarie Marshes, following extensive flooding, most likely reflected the overall poor condition of native fish communities and low standing stocks of mature fish, resulting from deleterious long‐term effects of flow regulation exacerbated by drought. A gradual rebuilding of ecosystem health, fish health, and resilient fish populations by active management of environmental flows to impose more natural boom and bust dynamics may be needed to restore fish reproduction and recruitment in this regulated river.
Komodo dragons are not ecological analogs of apex mammalian predators
Authors: Jessop Tim S. , Ariefiandy Achmad , Forsyth David M. , Purwandana Deni , White Craig R. , Benu Yunias Jackson , Madsen Thomas , Harlow Henry J. , Letnic Mike
Published: January 2020

Apex predators can have substantial and complex ecological roles in ecosystems. However, differences in species‐specific traits, population densities, and interspecific interactions are likely to determine the strength of apex predators’ roles. Here we report complementary studies examining how interactions between predator per capita metabolic rate and population density influenced the biomass, population energy use, and ecological effects of apex predators on their large mammalian prey. We first investigated how large mammal prey resources and field metabolic rates of terrestrial apex predators, comprising large mammals and the Komodo dragon (Varanus komodoensis), influenced their biomass densities and population energy use requirements. We next evaluated whether Komodo dragons, like apex mammalian predators, exerted top‐down regulation of their large mammal prey. Comparison of results from field studies demonstrates that Komodo dragons attain mean population biomass densities that are 5.75−231.82 times higher than that of apex mammalian predator species and their guilds in Africa, Asia, and North America. The high biomass of Komodo dragons resulted in 1.96−108.12 times greater population energy use than that of apex mammalian predators. Nevertheless, substantial temporal and spatial variation in Komodo dragon population energy use did not regulate the population growth rates of either of two large mammal prey species, rusa deer (Rusa timorensis) and wild pig (Sus scrofa). We suggest that multiple processes weaken the capacity of Komodo dragons to regulate large mammal prey populations. For example, a low per capita metabolic rate requiring an infrequent and inactive hunting strategy (including scavenging), would minimize lethal and nonlethal impacts on prey populations. We conclude that Komodo dragons differ in their predatory role from, including not being the ecological analogs of, apex mammalian predators.
The role of conflict framing and social identity in public opinion about land use change: An experimental test in the Australian context
Authors: Colvin R. M. , Witt G. Bradd , Lacey Justine , McCrea Rod
Published: January 2020

Decision makers use public opinion as an indicator of social acceptance for land use changes. However, public opinion is informed by, inter alia, the media, which tends to “frame” issues of public interest in terms of social conflict rather than the substantive details of the issue. Previous research about the influence of conflict on public opinion about politics has yielded contradictory results about the effect of this “conflict framing.” Some studies have shown that conflict framing polarises public opinion, whereas others have found that it moderates public opinion. Similarly, there is no clear understanding of how conflict framing may affect public opinion about the social acceptance of land use changes. This study presents an experimental survey with a quota sample of the Australian population (n = 1,147) where fictional land use change headlines were manipulated to represent three levels of conflict framing (no conflict; conflict; and conflict between identified parties). The results showed that heightened conflict framing led to the strength of support or opposition for land use changes to become weaker. Importantly, these findings show that perceived social conflict can shape public opinion on land use change. As a consequence, public opinion may not represent genuine social acceptance of land use change in cases where conflict is pronounced in the media. This raises the need for attentiveness to disentangling the influence of conflict framing from the substantive issues of land use change.
Comparison of symptomatic and functional responses to vagus nerve stimulation in ANTHEM‐HF, INOVATE‐HF, and NECTAR‐HF
Authors: Anand Inder S. , Konstam Marvin A. , Klein Helmut U. , Mann Douglas L. , Ardell Jeffrey L. , Gregory Douglas D. , Massaro Joseph M. , Libbus Imad , DiCarlo Lorenzo A. , Udelson John James E. , Butler Javed , Parker John D. , Teerlink John R.
Published: January 2020

Aims

Clinical studies of vagal nerve stimulation (VNS) for heart failure with reduced ejection fraction have had mixed results to date. We sought to compare VNS delivery and associated changes in symptoms and function in autonomic regulation therapy via left or right cervical vagus nerve stimulation in patients with chronic heart failure (ANTHEM‐HF), increase of vagal tone in heart failure (INOVATE‐HF), and neural cardiac therapy for heart failure (NECTAR‐HF) for hypothesis generation.

Methods and results

Descriptive statistics were used to analyse data from the public domain for differences in proportions using Pearson's chi‐square test, differences in mean values using Student's unpaired t‐test, and differences in changes of mean values using two‐sample t‐tests.

Guideline‐directed medical therapy recommendations were similar across studies. Fewer patients were in New York Heart Association 3, and baseline heart rate (HR) was higher in ANTHEM‐HF. In INOVATE‐HF, VNS was aimed at peripheral neural targets, using closed‐loop delivery that required synchronization of VNS to R‐wave sensing by an intracardiac lead. Pulse frequency was low (1–2 Hz) because of a timing schedule allowing ≤3 pulses of VNS following at most 25% of detected R waves. NECTAR‐HF and ANTHEM‐HF used open‐loop VNS delivery (i.e. independent of any external signal) aimed at both central and peripheral targets. In NECTAR‐HF, VNS delivery at 20 Hz caused off‐target effects that limited VNS up‐titration in a majority of patients. In ANTHEM‐HF, VNS delivery at 10 Hz allowed up‐titration until changes in HR dynamics were confirmed. Six months after VNS titration, significant improvements in both HR and HR variability occurred only in ANTHEM‐HF. When ANTHEM‐HF and NECTAR‐HF were compared, greater improvements from baseline were observed in ANTHEM‐HF in standard deviation in normal‐to‐normal R‐R intervals (94 ± 26 to 111 ± 50 vs. 146 ± 48 to 130 ± 52 ms; P < 0.001), left ventricular ejection fraction (32 ± 7 to 37 ± 0.4 vs. 31 ± 6 to 33 ± 6; P < 0.05), and Minnesota Living with Heart Failure mean score (40 ± 14 to 21 ± 10 vs. 44 ± 22 to 36 ± 21; P < 0.002). When compared with INOVATE‐HF, greater improvement in 6‐min walk distance was observed in ANTHEM‐HF (287 ± 66 to 346 ± 78 vs. 304 ± 111 to 334 ± 111 m; P < 0.04).

Conclusions

In this post‐hoc analysis, differences in patient demographics were seen and may have caused the differential responses in symptoms and function observed in association with VNS. Major differences in technology platforms, neural targets, VNS delivery, and HR and HR variability responses could have also potentially played a very important role. Further study is underway in a randomized controlled trial with these considerations in mind.
Economic impact of heart failure with preserved ejection fraction: insights from the ALDO‐DHF trial
Authors: Hashemi Djawid , Dettmann Ludwig , Trippel Tobias D. , Holzendorf Volker , Petutschnigg Johannes , Wachter Rolf , Hasenfuß Gerd , Pieske Burkert , Zapf Antonia , Edelmann Frank
Published: January 2020

Aims

Although heart failure (HF) with preserved ejection fraction (HFpEF) is a leading cause for hospitalization, its overall costs remain unclear.

Therefore, we assessed the health care‐related costs of ambulatory HFpEF patients and the effect of spironolactone.

Methods and results

The aldosterone receptor blockade in diastolic HF trial is a multicentre, prospective, randomized, double‐blind, placebo‐controlled trial conducted between March 2007 and April 2011 at 10 sites in Germany and Austria that included 422 ambulatory patients [mean age: 67 years (standard deviation: 8); 52% women]. All subjects suffered from chronic New York Heart Association (NYHA) class II or III HF and preserved left ventricular ejection fraction of 50% or greater. They also showed evidence of diastolic dysfunction.

Patients were randomly assigned to receive 25 mg of spironolactone once daily (n = 213) or matching placebo (n = 209) with 12 months of follow‐up. We used a single‐patient approach to explore the resulting general cost structure and included medication, number of general practitioner and cardiologist visits, and hospitalization in both acute and rehabilitative care facilities.

The average annual costs per patient in this cohort came up to €1, 118 (±2,475), and the median costs were €332. We confirmed that the main cost factor was hospitalization and spironolactone did not affect the overall costs. We identified higher HF functional class (NYHA), male patients with low haemoglobin level, with high oxygen uptake (VO2max) and coronary artery disease, hyperlipidaemia, and atrial fibrillation as independent predictors for higher costs.

Conclusions

In this relatively young, oligosymptomatic, and with regard to the protocol without major comorbidities patient cohort, the overall costs are lower than expected compared with the HFrEF population. Further investigation is needed to investigate the impact of, for example, comorbidities and their effect over a longer period of time. Simultaneously, this analysis suggests that prevention of comorbidities are necessary to reduce costs in the health care system.