bluuebunny/crossref_metadata_2025 huggingface dataset:
Precise synthesis of heterogeneous glycopolymers with well‐defined saccharide motifs in the side chain via post‐polymerization modification and recognition with lectin
Authors: Liu Meina , Miao Dengyun , Wang Xingyou , Wang Caiyun , Deng Wei
Published: July 2020

Heterogeneous glycopolymers with different sugar units in the side chain have been receiving considerable attention due to their potential properties in enhancing molecular recognition abilities toward a specific receptor, yet there are limited synthetic approaches to introduce different sugar motifs into the glycopolymer backbone. Herein, a series of heterogeneous glycopolymers consisting of different sugar units in the side chains were synthesized by post‐polymerization modification of activated PFPA ester precursor polymers. The functionalized amines bearing two different sugar motifs have been synthesized by gradient CuAAC reaction, which could serve as a platform for achieving heterogeneous sugar units with functional control in concise steps. Isothermal titration calorimetry (ITC) measurements of the obtained glycopolymers with Concanavalin A indicated that the heterogeneous glycopolymers, poly(Man‐βGlu‐OH) and poly(Man‐βGa‐OH) bearing α‐D‐mannose and other non‐binding β‐Glucose or β‐Galatose units, show higher affinities toward Concanavalin A in comparison to monoglycopolymer poly(Man‐Alkyne‐OH) in which the non‐binding sugar motifs was substituted with non‐sugar unit due to synergistic effects of non‐binding sugar units. Moreover, this work allows for precise fabrication of a broad variety of glycopolymers in which it significantly broadens the library of accessible polymer structures, either homogeneous or heterogeneous glycopolymers.
Preparation, characterization, and dilute solution properties of four‐branched cage‐shaped poly(ethylene oxide)
Authors: Noda Takashi , Doi Yuya , Ohta Yutaka , Takata Shin‐ichi , Takano Atsushi , Matsushita Yushu
Published: July 2020

A four‐branched cage‐shaped poly(ethylene oxide) (4C‐PEO) was prepared by a coupling reaction at very dilute condition between two kinds of end‐functional four‐armed star‐shaped PEOs having amino and N‐hydroxysuccinimide groups on their four ends, followed by purification using α‐cyclodextrin (α‐CD). The raw coupling reaction product shows multiple peaks including various high molecular weight multimeric products in size‐exclusion chromatography measurements, while the product after α‐CD purification shows a single peak eluted slightly earlier than the precursor star PEOs. Moreover, the final product obtained has about twice higher molecular weight than the star precursors. These results suggest that the targeted 4C‐PEO polymer was successfully isolated through the α‐CD purification. Small‐angle neutron scattering (SANS) measurements of the final product in dilute solution were conducted, and its chain conformation was evaluated from the scattering profile in comparison with linear and star polymers. It has been found that the cage‐shaped sample exhibits a distinct peak at lower q‐region in the Kratky plot, which is in strong contrast with the linear counterpart. This result must be originated from the characteristic cage‐shaped architecture, that is, having branched and closed‐loop configurations, and hence having higher segmental density than simple linear and star molecules. In fact, the present experimental result is consistent with the recent Monte Carlo simulation reported by Uehara and Deguchi.
Phase II Dose Selection for Alpha Synuclein–Targeting Antibody Cinpanemab (BIIB054) Based on Target Protein Binding Levels in the Brain
Authors: Kuchimanchi Mita , Monine Michael , Kandadi Muralidharan Kumar , Woodward Caroline , Penner Natalia
Published: July 2020

This modeling and simulation analysis was aimed at selecting doses of cinpanemab (BIIB054), a monoclonal antibody targeting aggregated α‐synuclein, for a phase II study in Parkinson’s disease (PD). Doses and regimens were proposed based on anticipated target concentration in brain interstitial fluid (ISF); in vitro/in vivo data on the affinity of monoclonal antibodies to the target protein; and safety, tolerability, and pharmacokinetic data (1–135 mg/kg intravenous administration) from a phase I single ascending dose (SAD) study. A population pharmacokinetic modeling approach was used to select intravenous doses of 250, 1,250, and 3,500 mg every 4 weeks, to maintain 50%, 90%, and > 90% of target binding in ISF of PD participants. A favorable safety profile from the SAD study—which showed that cinpanemab was generally well‐tolerated at doses up to 90 mg/kg, supported by modeling and simulations of the anticipated safety margins—allowed implementation of a fixed‐dose approach.
High‐Performance Broadband Tungsten Disulfide Photodetector Decorated with Indium Arsenide Nanoislands
Authors: Yang Yuekun , Liu Guanyu , Li Panlin , Zhang Miao , Wang Jianlu , Hu Weida , Xue Zhongying , Di Zengfeng
Published: July 2020

The 2D tungsten disulfide (WS2), as a typical transition metal dichalcogenide (TMD), has aroused intense research interests in photodetection. However, the limited detection wavelength ranges and low photoresponsivity hinder its further application. To promote the application of WS2 in optoelectronics fields, indium arsenide (InAs) nanoislands decorated WS2 are utilized to fabricate photodetectors in this work. Owing to the photogating effect and localized surface plasmon resonance (LSPR), a significant enhancement of photocurrent response (≈1 mA W−1) is obtained by coupling WS2 with InAs nanoislands. Furthermore, the extended detection wavelength up to 1060 nm is realized due to the efficient light absorption in IR range of InAs nanoislands. The high performance, stability, and reliability in ambient temperature strongly indicate that the InAs nanoislands/WS2 heterostructure can be considered as a promising material for TMDs‐based broadband optoelectronic devices in the future.
Informative Aspects of Molten KOH Etch Pits Formed at Basal Plane Dislocations on the Surface of 4H‐SiC
Authors: Nishio Johji , Ota Chiharu , Okada Aoi , Iijima Ryosuke
Published: July 2020

Despite being a destructive technique, molten KOH etch pits at basal plane dislocations are found to have informative aspects, as revealed by photoluminescence imaging and optical microscopy, on the 4° off‐cut (0001) surface of 4H‐SiC p–i–n diode chips, where single Shockley‐type stacking faults have expanded during electroluminescence experiments. Smaller etch pits are observed aligning on single lines along ±[100] that are the shallowest sides of stacking faults. Through closer observation of the pits, the facing directions are found to agree well with a model explaining the two types of partial dislocations constituting the line. Other basal plane dislocation pits are observed by scanning electron microscopy on the sublimation‐grown wafer surface before epitaxial growth. The distances between the partial dislocation cores are measured at each pit. No basal plane dislocation etch pit facing toward ±[100] is found, but a weak correlation is noted between the partial dislocation distance at the cores and the direction that the basal plane dislocations face. The corresponding results are discussed in terms of the image force and the force exerted on steps perpendicular to the (0001) plane, to understand the mechanisms of basal plane dislocation propagation and/or conversion to threading edge dislocations.
Low Current Densities Toggle Optical Polarization Switching in Pt/Yttrium Iron Garnet Magnetic Heterostructures Using Energy Resolution
Authors: Chien Wan-Hsiu Chang , Huang Jing-Ya , Lin Jun-Xiao , Liao Yen-Fa , Su Hung-Wen , Liang Hsia-Ling , Huang Ssu-Yen , Yao Yeong-Der , Hsu Hua-Shu
Published: July 2020

Spin current, which is converted from the charge current in heavy metals, is widely used to manipulate magnetization in heavy metal/magnetic insulator systems. However, there is scant research on how the spin‐polarized density of states (DOS) is affected by the absorption of spin current. This study investigates the spin‐current‐induced magnetic variation of an yttrium iron garnet (YIG) ﬁlm driven by charge current in an overlayer of Pt that uses energy‐resolved magnetic circular dichroism (MCD) spectra as an example. MCD intensity can be manipulated reversibly using an applied current at near d–d transitions. Furthermore, the MCD sign, which is associated with an elliptically polarized direction, is reversed by a relatively low current density (≈108 A m−2) near YIG charge transfer transitions, even without the assistance of a magnetic field. The spin accumulation in Fe orbits and the corresponding change in spin‐polarized DOS explain the observed phenomenon. This paves the way to low‐dissipation spintronics and electrically controlled magneto‐optical devices based on magnetic insulators.
Naringenin, a flavanone with antiviral and anti‐inflammatory effects: A promising treatment strategy against COVID‐19
Authors: Tutunchi Helda , Naeini Fatemeh , Ostadrahimi Alireza , Hosseinzadeh‐Attar Mohammad Javad
Published: July 2020

At the end of 2019, a novel flu‐like coronavirus named COVID‐19 (coronavirus disease 2019) was recognized by World Health Organization. No specific treatments exist for COVID‐19 at this time. New evidence suggests that therapeutic options focusing on antiviral agents may alleviate COVID‐19 symptoms as well as those that lead to the decrease in the inflammatory responses. Flavonoids, as phenolic compounds, have attracted considerable attention due to their various biological properties. In this review, the promising effects and possible mechanisms of action of naringenin, a citrus‐derived flavonoid, against COVID‐19 were discussed. We searched PubMed/Medline, Science direct, Scopus, and Google Scholar databases up to March 2020 using the definitive keywords. The evidence reviewed here indicates that naringenin might exert therapeutic effects against COVID‐19 through the inhibition of COVID‐19 main protease, 3‐chymotrypsin‐like protease (3CLpro), and reduction of angiotensin converting enzyme receptors activity. One of the other mechanisms by which naringenin might exert therapeutic effects against COVID‐19 is, at least partly, by attenuating inflammatory responses. The antiviral activity of the flavanone naringenin against some viruses has also been reported. On the whole, the favorable effects of naringenin lead to a conclusion that naringenin may be a promising treatment strategy against COVID‐19.
Effects of heterocyclic ring and amino‐ethyl‐amino group on the electronic and photophysical properties of a triphenylamine‐pyrimidine dye
Authors: Yang Jieqiong , Liu Dongzhi , Lu Ting , Sun Haiya , Li Wei , Testoff Thomas T. , Zhou Xueqin , Wang Lichang
Published: July 2020

Introduction of a heterocyclic ring and an amino‐ethyl‐amino group to donor‐acceptor (D‐A) type photosensitive dyes can modulate the lifetime of the charge separation generated in the D‐A dyes as well as their electronic and UV‐vis absorption properties. Here we perform density functional theory (DFT) and time‐dependent density functional theory (TD‐DFT) calculations to study 11 derivatives of a triphenylamine‐pyrimidine, namely MTPA‐Pyc, in order to improve the performance of MTPA‐Pyc as solar cell sensitizers. Five heterocyclic rings and an amino‐ethyl‐amino group were introduced on the styryl moiety of MTPA‐Pyc. The results show that the introduction of heterocyclic rings generally causes an absorption red shift, but the absorption intensity reduces as a result of the increase in the dihedral angle between the donor and acceptor. Further, introduction of an amino‐ethyl‐amino group to these dyes with a heterocyclic ring modification disrupts the conjugation between the donor and acceptor, which does not benefit the absorption but may have the potential to increase the lifetime of charge separation of the dyes. We identify 2 out of 11 dyes that have the best potential for solar cell applications.
Strain‐tunable electronic properties and optical properties of Hf2CO2 MXene
Authors: Li Shan‐Shan , Li Xiao‐Hong , Zhang Rui‐Zhou , Cui Hong‐Ling
Published: July 2020

Two‐dimensional materials have been extensively applied because of their unusual electronic, mechanical, and optical properties. In this paper, the electronic structure and optical properties of Hf2CO2 MXene under biaxial and uniaxial strains are investigated by the Heys‐Scuseria‐Ernzerhof (HSE06) method. Monolayer Hf2CO2 can sustain stress up to 6.453 N/M for biaxial strain and 3.072 N/M for uniaxial strain. Monolayer Hf2CO2 undergoes the transition from semiconductor to metal under −12% strain whether it is under biaxial or uniaxial strain. With the increasing biaxial compressive strain, the blue shift of Hf‐d, O‐p, and C‐p orbitals in valence band maximum results in the metallization of monolayer Hf2CO2, while the red shift of Hf‐d and O‐p orbitals in conduction band minimum results in the metallization of monolayer Hf2CO2 with increasing uniaxial compressive strain. The analysis of optical properties indicates that uniaxial strain weakens the reflectivity and refractive index of monolayer Hf2CO2 in the visible‐light range. In addition, the effective mass and the charge distribution under biaxial and uniaxial strains are also explored.
The effects of strain and charge doping on the electronic properties of graphitic C3N5
Authors: Yang Qiang , Cai Xing Hong , Pang Yong , Wang Min
Published: July 2020

Inspired by the successful synthesis of a new graphitic C3N5 (termed as g‐C3N5), we systematically investigate its geometry and electronic properties. The layered g‐C3N5 has a nanopore diameter of 13.8 Å. It is a direct semiconductor with a band gap of 0.53 eV. The influence of strains on the electronic properties is considered. When applying uniaxial or biaxial compressive strain, the band gap can decrease until zero, resulting in a semiconductor‐to‐metal transition. The effects of charge doping on the electronic properties are also studied. With the increase of negative charge doping, the band gap becomes narrow until zero, indicating that a semiconductor‐to‐metal transition occurs as well. In addition, the electronic properties of g‐C3N5 can be tuned by both strain and charge doping. Thus, we provide a fundamental understanding of g‐C3N5, and its semiconductor‐to‐metal transition could be possibly experimentally approached by strain and charge doping, extending the electronic usage of g‐C3N5.
Aggressive lung involvement in a patient with T‐acute lymphoblastic leukaemia/lymphoblastic lymphoma: a tricky and rare case report
Authors: Miyaoka Chika , Saraya Takeshi , Honda Kojiro , Fujiwara Masachika , Ishii Haruyuki , Takizawa Hajime
Published: July 2020

A 39‐year‐old man was admitted to our university hospital because of diffuse pulmonary infiltrates on chest X‐ray. He had been diagnosed with T‐acute lymphoblastic leukaemia/lymphoblastic lymphoma three years before and had been treated with chemotherapy and cord blood stem cell transplantation twice. Although he had neither blast cells in the peripheral blood nor leucocytosis, urgent bronchoscopy findings demonstrated blast cells invading both the alveolar spaces/alveolar septa and the vein walls. These pathological findings corresponded to ground‐glass opacities and thickening of the interlobular septa on thoracic computed tomography (CT). In acute lymphoblastic leukaemia/lymphoblastic lymphoma patients presenting with infiltrates on thoracic CT, leukaemic pulmonary involvement should be considered in the differential diagnoses, even in the absence of hyperleucocytosis or blast cells in the blood, similar to pulmonary involvement in myeloid leukaemias.
An automatic parameter calibration method for the SWAT model in runoff simulation
Authors: Wang Yongzhi , Zhu Sijing , Yuan Liu , Deng Rui
Published: July 2020

Runoff simulation is highly significant for hydrological monitoring, flood peak simulation, water resource management, and basin protection. Runoff simulation by distributed hydrological models, such as the soil and water assessment tool (SWAT) model which is the most widely used, is becoming a hotspot for hydrological forecasting research. However, parameter calibration is inefficient and inaccurate for the SWAT model. An automatic parameter calibration (APC) method of the SWAT model was developed by hybrid of the genetic algorithm (GA) and particle swarm optimization (PSO). Multi‐station and multi‐period runoff simulation and accuracy analysis were conducted in the basin of the Zhangjiang River on the basis of this hybrid algorithm. For example, in the Yaoxiaba Station, the calibration results produced an R2 of 0.87 and Nash Sutcliffe efficiency (NSE) index of 0.85, while verification results revealed an R2 of 0.83 and NSE of 0.83. Results of this study show that the proposed method can effectively improve the efficiency and simulation accuracy of the model parameters. It can be concluded that the feasibility and applicability of GA‐PSO as an APC method for the SWAT model were confirmed via case studies. The proposed method can provide theoretical guidance for many hydrological research fields, such as hydrological simulation, flood prevention, and forecasting.
Work function and negative electron affinity of ultrathin barium fluoride films
Authors: Mezzi Alessio , Bolli Eleonora , Kaciulis Saulius , Mastellone Matteo , Girolami Marco , Serpente Valerio , Bellucci Alessandro , Carducci Riccardo , Polini Riccardo , Trucchi Daniele M.
Published: July 2020

Thin films of barium fluorides with different thicknesses were deposited on GaAs substrate by electron beam evaporation. The aim of the work was to identify the best growth conditions for the production of coatings with a low work function suitable for the anode of hybrid thermionic‐photovoltaic (TIPV) devices. The chemical composition and work function φ of the films with different thicknesses were investigated by X‐ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). The lowest value of φ = 2.1 eV was obtained for the film with a thickness of ~2 nm. In the valence band spectra of the films at low kinetic energy, near the cutoff, a characteristic peak of negative electron affinity was present. This effect contributed to a further reduction of the film's work function.
Integrated Effect of Comonomer and Catalyst on Copolymerization of Ethylene with Allylcyclopentane or Allylcyclohexane by Using Metallocene Catalysts
Authors: Wang Wei , Hou Liping , Zhang Taoyi
Published: July 2020

An integrated effect of the catalysts and the comonomers has been observed when the copolymerizations of ethylene with allylcyclopentane or allylcyclohexane are conducted by using two metallocene catalysts. The effect results in the differences in the microstructure and macroscopic properties (e. g. the melting point and enthalpy) of the copolymers. Under the different combination of the catalysts and the comonomers, the microstructure of copolymer changes from ideal random to rich successive comonomer segment, although the two comonomers are very similar in the structure. Allylcyclohexane prefers to form the copolymer with the feature of rich successive comonomer segment, and the more random structure could be observed in the copolymer of allylcyclopentane. The catalyst used makes the difference even more pronounced.
Long‐Lasting Electrospun Co3O4 Nanofibers for Electrocatalytic Oxygen Evolution Reaction
Authors: Aljabour Abdalaziz
Published: July 2020

Electrocatalytic water splitting is one of the key phenomena in establishing renewable and sustainable energy technologies. Despite advances in hydrogen evolving industrial science, the oxygen electrochemistry lags behind due to the complexity in seeking suitable and stable electrocatalysts, in unifying electrolytic conditions and hence sluggish reaction kinetics. Herein, we report on the electrocatalytic activity of the cobalt oxide nanofibers in alkaline oxygen evolution reaction with a substantial operation lifetime of 120 hours. The unique preparation of fibers by electrospinning enables increased electrode networking and nanofibrous interaction thus leading to extended catalytically active surface area, imperative for well‐performing electrolysis. Operating at low overpotential of 293 mV at a current density of 10 mA cm−2, as well as low Tafel slope of 60.5 mV dec−1 in 1 M KOH indicate the efficient utilization of nanofibrous Co3O4 electrocatalyst towards oxygen evolution with an excellent long‐term durability over 100 hours.
Ultrasound‐Assisted Synthesis of Nitrogen and Oxygen Containing Heterocycles Using Fluorinated Graphene Oxide as Catalyst: Evaluation of Their Anthelmintic Activities
Authors: Dutta Arup , Chhetri Bhusan , Nongrum Ridaphun , Kupar Kharmawlong George , Yadav Arun K. , Nongkhlaw Rishanlang
Published: July 2020

Spirooxindole derivatives have been efficiently synthesized via a three‐component reaction consisting of isatin, malononitrile/ pyrazole and various 1,3‐diketones using Fluorinated Graphene Oxide (FGO) as a green and metal free carbocatalyst, under sonication. The main advantages of this synthetic approach lie in its operational simplicity, easy catalyst recovery and recyclability, high yields and short reaction times. The prepared catalyst was characterized by various analytical techniques viz., UV‐Vis, FT‐IR Spectroscopy, TGA, TEM, FE‐SEM and EDX. The in vitro anthelmintic screening of synthesized compounds against a cestode, Raillietina sp. and a nematode parasite, Syphacia obvelata at 200 μg/mL and 800 μg/mL were also carried out which revealed a profound activity, with much reduced morality time of parasite. The SEM study indicated structure alterations in treated parasite, further validating the in vitro anthelmintic property. In addition, molecular docking studies were carried out against β‐tubulin protein to determine binding affinity of the synthesized compounds. All test compound followed the “Lipinski Rule of Five” and in silico pharmacokinetic investigation showed inhibitory activity against CYP enzyme and P‐glycoprotein which may further improve the bio efficacy of compounds.
Fe(III)‐Functionalized Magnetic Covalent Organic Frameworks for Fast Adsorption and Removal of Phenylbutazone in Aqueous Solution
Authors: Zheng Ruijuan , Feng Dan , Xia Yan
Published: July 2020

An Fe(III) functionalized magnetic covalent organic framework, named MCOF(Fe), was fast synthesized at ambient temperature for the removal of phenylbutazone in aqueous solution. The adsorption kinetics, isotherms, and thermodynamics were investigated to describe the adsorption process. The effects of adsorption factors and regeneration were studied as well. The adsorption mechanism may be explained with electrostatic interaction, π‐π interaction, and hydrogen bonding between phenylbutazone and the adsorbent. A pseudo‐second‐order rate equation described the adsorption kinetics mechanisms was revealed effectively, and phenylbutazone was removed in 2 h. The multi‐site Langmuir‐Freundlich model fitted adsorption process well, and the maximum adsorption capacity for phenylbutazone was 60.04 mg g−1 at 25 °C. Recyclability experiments indicated that MCOF(Fe) could be regenerated at least 3 times without significant loss of adsorption capacity. Finally, it can be suggested that MCOF(Fe) having excellent performance can be attractive for removal phenylbutazone from aqueous solution.
Direct Synthesis of Phenols from Phenylboronic Acids in Aqueous Media Catalyzed by a Cu(0)‐Nanoparticles Biohybrid
Authors: McCarthy Caitlin , Losada‐Garcia Noelia , Palomo Jose M.
Published: July 2020

Selective hydroxylation of different phenylboronic acids to phenols was successfully carried out by using Cu nanoparticles‐enzyme hybrid catalysts in water and room temperature. Different Cu‐enzyme hybrids containing Cu(II), Cu(I) and Cu(0) nanoparticles species respectively were tested on the monohydroxylation of phenylboronic acid under these mild conditions being hybrids containing Cu(0)NPs the best catalysts, with total selectivity and formation of phenol as unique product. Also, the addition of hydrogen peroxide or the increase of reaction temperature were tested but did not improved these results. The substrate scope was also demonstrated and the Cu(0)NPs hybrid showed excellent results in the monohydroxylation of different o‐, m‐, p‐substituted phenylboronic acid with final yields >95 %. This catalyst showed excellent recyclability after 5 cycles of use.
Graphitic Carbon Nitride Stabilizers Meet Microfluidics: From Stable Emulsions to Photoinduced Synthesis of Hollow Polymer Spheres
Authors: Yandrapalli Naresh , Robinson Tom , Antonietti Markus , Kumru Baris
Published: July 2020

Graphitic carbon nitride (g‐CN) has been utilized as a heterogeneous catalyst, but is usually not very well dispersible. The amphiphilic character of g‐CN can be altered by surface modifications of g‐CN nanopowders. Introducing hydrophilicity or hydrophobicity is a promising avenue for producing advanced emulsion systems. In this study, a special surface‐modified g‐CN is used to form stable Pickering emulsions. Using a PDMS‐based microfluidic device designed for stable production of both single and double emulsions, it is shown that surface‐modified g‐CNs allow the manufacture of unconventionally stable and precise Pickering emulsions. Shell thickness of the double emulsions is varied to emphasize the robustness of the device and also to demonstrate the extraordinary stabilization brought by the surface‐modified carbon nitride used in this study. Due to the electrostatic stabilization also in the oil phase, double emulsions are centered. Finally, when produced from polymerizable styrene, hollow polymer microparticles are formed with precise and tunable sizes, where g‐CN is utilized as the only stabilizer and photoinitiator.
A Unique Double‐Layered Carbon Nanobowl‐Confined Lithium Borohydride for Highly Reversible Hydrogen Storage
Authors: Wu Ruyan , Zhang Xin , Liu Yongfeng , Zhang Lingchao , Hu Jianjiang , Gao Mingxia , Pan Hongge
Published: July 2020

Poor reversibility and high desorption temperature restricts the practical use of lithium borohydride (LiBH4) as an advanced hydrogen store. Herein, a LiBH4 composite confined in unique double‐layered carbon nanobowls prepared by a facile melt infiltration process is demonstrated, thanks to powerful capillary effect under 100 bar of H2 pressure. The gradual formation of double‐layered carbon nanobowls is witnessed by transmission electron microscopy (TEM) observation. Benefiting from the nanoconfinement effect and catalytic function of carbon, this composite releases hydrogen from 225 °C and peaks at 353 °C, with a hydrogen release amount up to 10.9 wt%. The peak temperature of dehydriding is lowered by 112 °C compared with bulk LiBH4. More importantly, the composite readily desorbs and absorbs ≈8.5 wt% of H2 at 300 °C and 100 bar H2, showing a significant reversibility of hydrogen storage. Such a high reversible capacity has not ever been observed under the identical conditions. The usable volumetric energy density reaches as high as 82.4 g L−1 with considerable dehydriding kinetics. The findings provide insights in the design and development of nanosized complex hydrides for on‐board applications.
Phosphorus‐Doped Iron Nitride Nanoparticles Encapsulated by Nitrogen‐Doped Carbon Nanosheets on Iron Foam In Situ Derived from Saccharomycetes Cerevisiae for Electrocatalytic Overall Water Splitting
Authors: Li Guixiang , Yu Jiayuan , Yu Wanqiang , Yang Linjing , Zhang Xiaoli , Liu Xiaoyan , Liu Hong , Zhou Weijia
Published: July 2020

It is vitally essential to propose a novel, economical, and safe preparation method to design highly efficient electrocatalysts. Herein, phosphorus‐doped iron nitride nanoparticles encapsulated by nitrogen‐doped carbon nanosheets are grown directly on the iron foam substrate (P‐Fe3N@NC NSs/IF) by in situ deriving from Saccharomycetes cerevisiae (S. cerevisiae), where anion elements of C, N, and P all from S. cerevisiae replace the hazardous CH4, NH3, and H3P. The diffusion pattern of N, P in S. cerevisiae and contact form between metal and S. cerevisiae observably affect the composition and phase of the product during high‐temperature calcination. The obtained P‐Fe3N@NC NSs/IF demonstrates superior electrocatalytic performance for the hydrogen evolution reaction and oxygen evolution reaction, also satisfying durability. Theoretical calculation confirms that Fe sites of P‐Fe3N serve as the active center, and N sites and P doping regulate the hydrogen binding strength to enhance catalytic ability. Additionally, the two‐electrode electrolyzer assembled by P‐Fe3N@NC NSs/IF as both anode and cathode electrodes needs only 1.61 V to reach 10 mA cm−2 for overall water splitting with a superb stability. The S. cerevisiae‐based process presents a feasible approach for synthesis of nitrides, carbides, phosphides, and electrocatalytic applications.
Hierarchically Well‐Developed Porous Graphene Nanofibers Comprising N‐Doped Graphitic C‐Coated Cobalt Oxide Hollow Nanospheres As Anodes for High‐Rate Li‐Ion Batteries
Authors: Lee Jae Seob , Jo Min Su , Saroha Rakesh , Jung Dae Soo , Seon Young Hoe , Lee Jun Su , Kang Yun Chan , Kang Dong‐Won , Cho Jung Sang
Published: July 2020

Hierarchically well‐developed porous graphene nanofibers comprising N‐doped graphitic C (NGC)‐coated cobalt oxide hollow nanospheres are introduced as anodes for high‐rate Li‐ion batteries. For this, three strategies, comprising the Kirkendall effect, metal–organic frameworks, and compositing with highly conductive C, are applied to the 1D architecture. In particular, NGC layers are coated on cobalt oxide hollow nanospheres as a primary transport path of electrons followed by graphene‐nanonetwork‐constituting nanofibers as a continuous and secondary electron transport path. Superior cycling performance is achieved, as the unique nanostructure delivers a discharge capacity of 823 mAh g−1 after 500 cycles at 3.0 A g−1 with a low decay rate of 0.092% per cycle. The rate capability is also noteworthy as the structure exhibits high discharge capacities of 1035, 929, 847, 787, 747, 703, 672, 650, 625, 610, 570, 537, 475, 422, 294, and 222 mAh g−1 at current densities of 0.5, 1.5, 3, 5, 7, 10, 12, 15, 18, 20, 25, 30, 40, 50, 80, and 100 A g−1, respectively. In view of the highly efficient Li+ ion/electron diffusion and high structural stability, the present nanostructuring strategy has a huge potential in opening new frontiers for high‐rate and long‐lived stable energy storage systems.
Temperature‐Dependent Tip‐Induced Motion of Ga Adatom on GaAs (110) Surface
Authors: Kaku Shigeru , Yoshino Junji
Published: July 2020

The temperature‐dependent tip‐induced‐motion of a Ga adatom on a GaAs (110) surface is experimentally demonstrated using scanning tunneling microscopy (STM). The surface adsorption energy profile obtained by first‐principle electronic structure calculations reveals that the origin of the Ga motion observed at 78 K is attributable to the tip‐induced Ga adatom hopping between the most stable potential minima among the three local minima, whereas that observed at 4.2 K is attributable to the tip‐induced hopping and sliding motions through the next stable minima as well as the most stable minima. Furthermore, it is shown that a slight progressive modification of the adatom motion observed only at 4.2 K resulting from repeated STM line scans is consistent with the overall picture taking account of the heating of the adatom owing to the tip current.
Critical considerations for trimethylsilyl derivatives of 24 primary metabolites measured by gas chromatography–tandem mass spectrometry
Authors: Engel Benedikt , Suralik Peter , Marchetti‐Deschmann Martina
Published: July 2020

Cellular reactions are very important for biological systems and understanding metabolic changes is therefore crucial. Here, a gas chromatography–tandem mass spectrometry method based on multiple reaction monitoring is presented, increasing specificity and sensitivity of the method. Twenty‐four metabolites of the primary carbon metabolism were selected for method development as representatives of different analyte classes (carbohydrates and their phosphates, amino acids, organic acids). The derivatization strategy necessary for analysis includes trimethylsilyl derivatization or its combination with methoximation. Derivatization products and reaction kinetics were carefully studied and compared. It is shown in detail that mere silylation results in up to seven monosaccharide derivatives and that irregular derivatization products were observed for particular amino acids showing either one or two silylation products for the ε‐amino groups. Additionally, it was found that there is not a defined endpoint for this reaction. Methoximation/silylation was also optimized and studied in detail (time, temperature, kinetics) and showed reduced complexity for the derivatization products. However, some metabolites exhibited significantly lower signal responses. Most interestingly, it was observed that in the presence of amino acids the derivatization products for monosaccharides are altered when compared to monosaccharide standards, as demonstrated by the detailed discussion of glucose derivatization in the presence of lysine.
Platform to study intracellular polystyrene nanoplastic pollution and clinical outcomes
Authors: Bojic Sanja , Falco Matias M. , Stojkovic Petra , Ljujic Biljana , Gazdic Jankovic Marina , Armstrong Lyle , Markovic Nebojsa , Dopazo Joaquin , Lako Majlinda , Bauer Roman , Stojkovic Miodrag
Published: July 2020

Increased pollution by plastics has become a serious global environmental problem, but the concerns for human health have been raised after reported presence of microplastics (MPs) and nanoplastics (NPs) in food and beverages. Unfortunately, few studies have investigate the potentially harmful effects of MPs/NPs on early human development and human health. Therefore, we used a new platform to study possible effects of polystyrene NPs (PSNPs) on the transcription profile of preimplantation human embryos and human induced pluripotent stem cells (hiPSCs). Two pluripotency genes, LEFTY1 and LEFTY2, which encode secreted ligands of the transforming growth factor-beta, were downregulated, while CA4 and OCLM, which are related to eye development, were upregulated in both samples. The gene set enrichment analysis showed that the development of atrioventricular heart valves and the dysfunction of cellular components, including extracellular matrix, were significantly affected after exposure of hiPSCs to PSNPs. Finally, using the HiPathia method, which uncovers disease mechanisms and predicts clinical outcomes, we determined the APOC3 circuit, which is responsible for increased risk for ischemic cardiovascular disease. These results clearly demonstrate that better understanding of NPs bioactivities and its implications for human health is of extreme importance. Thus, the presented platform opens further aspects to study interactions between different environmental and intracellular pollutions with the aim to decipher the mechanism and origin of human diseases.
Novel Two‐Dimensional Porous Materials for Electrochemical Energy Storage: A Minireview
Authors: Mao Lei , Zhao Xun , Wang Huayu , Xu Hong , Xie Li , Zhao Chenglan , Chen Lingyun
Published: July 2020

Two dimensional (2D) porous materials have great potential in electrochemical energy conversion and storage. Over the past five years, our research group has focused on Simple, Mass, Homogeneous and Repeatable Synthesis of various 2D porous materials and their applications for electrochemical energy storage especially for supercapacitors (SCs). During the experimental process, through precisely controlling the experimental parameters, such as reaction species, molar ratio of different ions, concentration, pH value of reaction solution, heating temperature, and reaction time, we have successfully achieved the control of crystal structure, composition, crystallinity, morphology, and size of these 2D porous materials including transition metal oxides (TMOs), transition metal hydroxides (TMHOs), transition metal oxalates (TMOXs), transition metal coordination complexes (TMCCs) and carbon materials, as well as their derivatives and composites. We have also named some of them with CQU‐Chen (CQU is the initialism of Chongqing University, Chen is the last name of Lingyun Chen), such as CQU‐Chen‐Co−O‐1, CQU‐Chen‐Ni−O−H‐1, CQU‐Chen‐Zn−Co−O‐1, CQU‐Chen‐Zn−Co−O‐2, CQU‐Chen‐OA−Co‐2‐1, CQU‐Chen‐Co−OA‐1, CQU‐Chen‐Ni−OA‐1, CQU‐Chen‐Gly−Co‐3‐1, CQU‐Chen‐Gly−Ni‐2‐1, CQU‐Chen‐Gly−Co−Ni‐1, etc. The introduction of 2D porous materials as electrode materials for SCs improves the energy storage performances. These materials provide a large number of active sites for ion adsorption, supply plentiful channels for fast ion transport and boost electrical conductivity and facilitate electron transportation and ion penetration. The unique 2D porous structures review is mainly devoted to the introduction of our contribution in the 2D porous nanostructured materials for SC. Finally, the further directions about the preparation of 2D porous materials and electrochemical energy conversion and storage applications are also included.
Characterization of the ablation zones produced by three commercially available systems from a single vendor for radiofrequency thermoablation in an ex vivo swine liver model
Authors: Bullone Michela , Garberoglio Roberto , Pregel Paola , Cannizzo Francesca T. , Gagliardo Arianna , Martano Marina , Bollo Enrico , Scaglione Frine E.
Published: July 2020

Background

Radiofrequency Ablation (RFA) is rarely performed in veterinary medicine. A rationale exists for its use in selected cases of canine liver tumours. RFA induces ablation zones of variable size and geometry depending on the technique used and on the impedance of the targeted organ.

Objectives

(a) to describe the geometry and reproducibility of the ablation zones produced by three commercially available systems from a single company, using isolated swine liver parenchyma as a model for future veterinary applications in vivo; (b) to study the effects of local saline perfusion into the ablated parenchyma through the electrode tip and of single versus double passage of the electrode on size, geometry and reproducibility of the ablation zones produced.

Methods

Size, and geometry of ablation zones reproduced in six livers with one cooled and perfused (saline) and two cooled and non‐perfused systems, after single or double passage (n = 6/condition), were assessed macroscopically on digitalized images by a blinded operator. Longitudinal and transverse diameters, equivalent diameter, estimated volume and roundness index were measured. Reproducibility was assessed as coefficient of variation.

Results and Conclusions

Ablation zone reproducibility was higher when expressed in terms of ablation zone diameters than estimated volume. Local saline perfusion of the parenchyma through the electrode tip during RFA increased the ablation zone longitudinal diameter. Ablation zone estimated volume increased with saline perfusion only when double passage was performed. These data may provide useful information for those clinicians who intend to include RFA as an additive tool in veterinary interventional radiology.
Gambel's Quail Survey Variability and Implications for Survey Design in the Mojave Desert
Authors: Overton Cory T. , Casazza Michael L. , Connelly Daniel , Gardner Scott
Published: July 2020

Careful design of a wildlife population monitoring strategy is necessary to obtain accurate and precise results whether the purpose of the survey is development of habitat suitability models, to estimate abundance, or assess site occupancy. Important characteristics to consider in survey design are sources of elevated variability, particularly within‐subject variability, which increases the amount of data needed to achieve statistical certainty either in terms of population trend analysis, hypothesis testing, or statistical power. However, alternative objectives, such as associating counts with habitat characteristics, may benefit from increased variation among counts when differences covary with habitat measures. This difference can result in competing needs when developing survey protocols. We investigated the relative precision of differing gamebird monitoring protocols to identify methods with the greatest statistical efficiency. We assessed call‐count transects using standard Breeding Bird Survey protocols (Passive call‐counts) and modified by including longer survey periods and call playback (Active call‐counts), autonomous recording units with supervised call detection (ARU‐recorded calls), camera traps, and roadside covey‐counts for Gambel's quail (Callipepla gambelii) in the Mojave Desert (CA, USA) during the spring of 2016. Active call‐counts had the lowest within‐site variation relative to estimated population index values, but Passive call‐count transects may be more efficient for some purposes because more survey stations can be completed within a single survey timeframe. The ARU‐recorded calls may provide a suitable alternative despite larger sample size needs, especially for occupancy surveys because multiple units can be deployed concurrently. The ultimate sample size required will depend on specific study objectives and scope of interest, but camera traps and breeding‐season covey counts are not likely to meet objectives in desert environments. © 2020 The Wildlife Society.
Computing the p-modulus of systems of measures via optimal plans
Authors: Ciska-Niedziałomska Małgorzata
Published: July 2020

We use the notion of the optimal plan associated with the Fuglede p-modulus of a family of Borel measures to derive formulas for the p-modulus and the extremal function in many special cases. Among others, we deduce Rodin’s formula for a family of Hausdorff measures associated with leaves of a foliation defined by a single chart.
Analysis of improved Nernst–Planck–Poisson models of compressible isothermal electrolytes
Authors: Dreyer Wolfgang , Druet Pierre-Étienne , Gajewski Paul , Guhlke Clemens
Published: July 2020

We consider an improved Nernst–Planck–Poisson model first proposed by Dreyer et al. in 2013 for compressible isothermal electrolytes in non-equilibrium. The elastic deformation of the medium, that induces an inherent coupling of mass and momentum transport, is taken into account. The model consists of convection–diffusion–reaction equations for the constituents of the mixture, of the Navier–Stokes equation for the barycentric velocity and of the Poisson equation for the electrical potential. Due to the principle of mass conservation, cross-diffusion phenomena must occur, and the mobility matrix (Onsager matrix) has a non-trivial kernel. In this paper, we establish the existence of a global-in-time weak solution, allowing for a general structure of the mobility tensor and for chemical reactions with fast nonlinear rates in the bulk and on the active boundary. We characterise the singular states of the system, showing that the chemical species can vanish only globally in space, and that this phenomenon must be concentrated in a compact set of measure zero in time.
A one-stop perineal clinic: our eleven-year experience
Authors: Wan Osanna Yee Ki , Taithongchai Annika , Veiga Susana I. , Sultan Abdul H. , Thakar Ranee
Published: July 2020

Introduction and hypothesis

The perineal clinic is a dedicated setting offering assessment for various childbirth-related presentations including obstetric anal sphincter injuries (OASIs), perineal wound complications, pelvic floor dysfunction and other conditions such as female genital mutilation(FGM). We describe the clinical presentation and outcomes of women from a tertiary perineal clinic based on data collected over an 11-year period.

Methods

This is a retrospective observational study. A one-stop outpatient service was offered to all women who sustained OASIs (postnatally and antenatally in a subsequent pregnancy), perineal complications (within 16 weeks postpartum), FGM and/or peripartum symptoms of urinary/anal incontinence or prolapse. Assessment included history with validated questionnaires, examination and anal manometry and endoanal ultrasound when appropriate. Outcomes were compared among different grades of OASIs. Management of each type of presentation was reported with outcomes.

Results

There were 3254 first attendance episodes between 2006 and 2016. The majority (58.1%) were for OASIs, followed by perineal wound complications. Compared to the lower grades, the higher grades of OASI were associated with poorer outcomes in terms of symptoms, investigations and complications. Women with OASIs had unrelated symptoms such as urinary incontinence, perineal pain and wound infections that needed further intervention. A high proportion(42%) of wound complications required further specialist management.

Conclusion

We describe a dedicated, one-stop perineal clinic model for antenatal and postnatal women for management of perineal and pelvic floor disorders. This comprehensive and novel data will enable clinicians to better counsel women regarding of outcomes after OASI and focus training to minimize risks of morbidities.
Clinical characteristics and comparison of the outcome in young versus older patients with upper gastrointestinal carcinoma
Authors: Puhr Hannah Christina , Karner Alexander , Taghizadeh Hossein , Jomrich Gerd , Schoppmann Sebastian Friedrich , Preusser Matthias , Ilhan-Mutlu Aysegül
Published: July 2020

Background

The clinical behaviour and outcome of young patients with gastroesophageal tumours (GET) is surmised to differ from older patients, yet data on the comparison of these two patient subgroups is scarce. This study focuses on the investigation of the clinical characteristics and survival outcome of younger-age people with GET, when compared to older patients.

Methods

Patients diagnosed with GET at the Medical University of Vienna between 2004 and 2016 were included in this study. Clinical parameters and the overall survival (OS) were compared between young (≤ 45 years) and elderly (≥ 65 years) patients.

Results

Among 796 patients, who were eligible for this analysis, fifty-eight patients (7%) were ≤ 45 years at the initial onset of the disease. These 58 young patients were then matched to elderly patients based on the gender, tumour stage, histology and tumour location. The number of metastatic lesions was significantly higher among young patients (p < 0.05). In a non-metastatic setting younger patients showed a significant longer OS than older patients (median 1226 versus 801 days, p = 0.028). Furthermore, young patients with extensive metastatic disease (2 or more metastatic site) had a significantly poorer OS than elderly patients (median 450 versus 646 days, p = 0.033).

Conclusion

These results indicate that young patients might be diagnosed very late, which might lead to the development of a more aggressive disease compared to older patients, but a relatively long OS when diagnosed and treated in a non-metastatic setting. Thus, screening methods for younger patients might be considerable to enhance the outcome of young patients with GET.
A numerical method for the generation of hierarchical Poisson Voronoi microstructures applied in micromechanical finite element simulations—part I: method
Authors: Schneider Y. , Weber U. , Wasserbäch W. , Zielke R. , Schmauder S. , Tillmann W.
Published: July 2020

Poisson Voronoi (PV) tessellations as artificial microstructures are widely used in investigations of material deformation behaviors. However, a PV structure usually describes a relative homogeneous field. This work presents a simple numerical method for generating 2D/3D artificial microstructures based on hierarchical PV tessellations. If grains/particles of a phase cover a large size span, the concept of “artificial phases” can be used to create a more realistic size distribution. From case to case, detailed microstructural features cannot be directly achieved by commercial or free softwares, but they are necessary for a deep or thorough study of the material deformation behavior. PV tessellations created in our process can fulfill individual requirements from material designs. Another reason to use PV tessellations is due to the limited experimental data. Concerning the application of PV microstructures, four examples are given. The FE models and results will be presented in consecutive works, i.e. “part II: applications”.