bluuebunny/crossref_metadata_2025 huggingface dataset:
Initiation of nanosecond-pulsed discharge in water: Electrostriction effect
Authors: Li Yuan , Li Lin-Bo , Wen Jia-Ye , Ni Zheng-Quan , Zhang Guan-Jun ,   State Key Laboratory of Electrical Insulation and Power Equipment, School of Electrical Engineering,  Xi’an Jiaotong University, Xi’an 710049, China
Published: January 2021

Underwater nanosecond-pulsed discharges have been widely utilized in numerous industrial applications. The initial stage of nanosecond-pulsed discharge in water contains extremely abundant physical processes, however, it is still difficult to reveal the details of charge transportation and multiplicative process in liquid within several nanoseconds by currently existing experimental diagnostic techniques. Up to now, the initiation mechanism of underwater nanosecond discharge has been still a puzzle. In this paper, we develop a two-dimensional axially symmetric underwater discharge model of pin-to-plane, and numerically investigate the electrostriction process, cavitation process, and ionization process in water, induced by nanosecond-pulsed voltage. The negative pressure in water caused by tensile ponderomotive force is calculated. The creation of nanoscale cavities (so-called nanopores) in liquid due to negative pressure is modeled by classical nucleation theory with modified nucleation energy barrier. When estimating the temporal development of nanopore radius, a varying hydrostatic pressure is considered to restrain the unlimited expansion of nanopores. We estimate the electron generation rate by the product of the generation rate of incident electrons and the number density of nanopores. The simulation results show that cavitation occurs in liquid within several microns from pin electrode due to the electrostriction, which results in the formation of a large number of nanopores. The expansion of nanopore, caused by electrostrictive pressure on nanopore surface, provides a sufficient acceleration distance for electrons. The impact ionization of water molecules can be triggered by energetic electrons, leading the local liquid to be ionized rapidly. The effects of nanopores on rapid electron generation in water are discussed. Once nanopores are formed, the electrons can be generated in the following ways: 1) Field ionization of water molecules on the nanopore wall continuously provides seed electrons; 2) the seed electrons accelerated in nanopores enter into the liquid and collide with water molecules, resulting in the rapid increase of electrons. It can be inferred that the randomly scattered nanopores act as micro-sources of charges that contribute to the continuing ionization of liquid water in cavitation region near pin electrode. Electrostriction mechanism provides a new perspective for understanding the initiation of nanosecond-pulsed discharge in water.
Photogating effect in two-dimensional photodetectors
Authors: Lei Ting , Lü Wei-Ming , Lü Wen-Xing , Cui Bo-Yao , Hu Rui , Shi Wen-Hua , Zeng Zhong-Ming ,   Key Laboratory of Multifunctional Nanomaterials and Smart Systems, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China,   School of Nano-Tech and Nano-Bionics, University of Science and Technology of China, Hefei 230026, China
Published: January 2021

In recent years, due to their unique physical, chemical and electronic properties, two-dimensional materials have received more and more researchers’ attention. In particular, the excellent optoelectronic properties and transport properties of two-dimensional materials such as graphene, black phosphorous and transition metal sulfide materials make them have broad application prospects in the field of next-generation optoelectronic devices. In this article, we will mainly introduce the advantages of two-dimensional materials in the field of photodetection, outline the basic principles and parameters of photodetectors, focus on the difference between the grating effect and the traditional photoconductive effect, and the reasons and characteristics of improving optical gain and optical responsivity. Then we review the latest developments and applications of grating local control in photodetectors, and finally summarize the problems faced by the photodetectors of this kind and their prospects for the future.
Valleytronic properties and devices based on two-dimensional atomic layer materials
Authors: Sun Zhen-Hao , Guan Hong-Ming , Fu Lei , Shen Bo , Tang Ning ,   State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, Peking University, Beijing 100871, China
Published: January 2021

Artificial manipulation of electronic degrees of freedom is the key point to realize modern electronic devices. Both charge and spin of electron have been widely studied and applied to logic circuits and information storage devices. Valley, the unique degree of freedom of crystal electrons, has also attracted great attention of the researchers in the past decade. The valleytronics progress benefits from the tremendous improvements of the two-dimensional atomic layer material growth technologies and in-depth explorations of valley properties. Valleytronic materials, represented by two-dimensional transition metal dichalcogenides, have become an excellent platform for the research and design of new electronic devices due to their special optical responses and distinctive electronic transport properties. The valley devices have the advantages of fast operation, low energy consumption, less information loss, high integration and long transmission distance.

In this review, we first introduce the basic concepts and properties of the energy valley, such as the valley Hall effect and the valley circular dichroism. Second, we describe the crystal structures and energy band diagrams of the two-dimensional transition metal dichalcogenides. Third, the progress in artificial manipulation of the valley effects is summarized. Some approaches which can break the inversion symmetry and therefore induce the valley degree of freedom are introduced. Fourth, we discuss the methods of realizing valley polarization. Fifth, the developments of valleytronic devices in recent years are reviewed. Finally, a summary and an outlook are given.
Measurement of radioactive residual nuclides induced in Cu target by 80.5 MeV/u carbon ions
Authors: Zhou Bin , Yu Quan-Zhi , Zhang Hong-Bin , Zhang Xue-Ying , Ju Yong-Qin , Chen Liang , Ruan Xi-Chao ,   Spallation Neutron Source Science Center, Dongguan 523803, China,   Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China,   Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China,   China Institute of Atomic Energy, Beijing 102413, China,   Songshan Lake Materials Laboratory, Dongguan 523808, China
Published: January 2021

Radioactive residual nuclides, which are usually closely related to radiation protection and personnel safety, will be generated when target materials are irradiated by high energy particles. Based on different nuclear reaction models, Monte Carlo code is a usual method to obtain residual nuclide production. The simulation accuracy needs to be evaluated by experimental data. In this paper, an irradiation experiment of thin copper target irradiated by 12C6+ particles with energy of 80.5 MeV/u is carried out. The radioactivities and cross-sections of 18 radioactive residual nuclides are obtained by gamma spectrometry analysis. Compared with the Monte Carlo simulation by PHITS, the results show that the spallation model of PHITS has a high reliability in estimating the types of radioactive residual nuclei, and it could be optimized in the aspect of the absolute yield.
Atomic scale characterization of three-dimensional structure, magnetic properties and dynamic evolutions of materials by transmission electron microscopy
Authors: Zhong Xiao-Yan , Li Zhuo ,   Department of Materials Science and Engineering, City University of Hong Kong, Kowloon 999077, China,   City University of Hong Kong Shenzhen Futian Research Institute, Shenzhen 518048, China,   Nanomanufacturing Laboratory (NML), City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China,   State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials (MOE), National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
Published: January 2021

Atomic scale characterization and manipulation is one of the physical bottlenecks, which needs to be broken when realizing atom manufacturing. The aberration-corrected transmission electron microscopy (TEM) is a powerful tool for structural characterization due to its exceptional spatial resolution. Therefore, it is very crucial to co-characterize atomic-scale three-dimensional structure and properties of atomic manufacturing materials by using TEM, which allows us to further understand the physics mechanism of atomic manipulation of materials. Nano-clusters and nanoparticles are two of the main objects in the studies of atomic manufacturing materials and devices, and possess rich physical and chemical properties and high manoeuverability. In this paper, we summarize the recent progress of quantitatively determining three-dimensional structures and magnetic properties of nanocluster, nanoparticles and nanograins, as well as their dynamic evolutions under the working conditions. The methodological breakthrough and development of electron microscopy techniques provide a solid foundation for precisely controlling atomic manufacturing materials.
A simple and effective F0 knockout method for rapid screening of behaviour and other complex phenotypes
Authors: Kroll François , Powell Gareth T , Ghosh Marcus , Gestri Gaia , Antinucci Paride , Hearn Timothy J , Tunbak Hande , Lim Sumi , Dennis Harvey W , Fernandez Joseph M , Whitmore David , Dreosti Elena , Wilson Stephen W , Hoffman Ellen J , Rihel Jason
Published: January 2021

Hundreds of human genes are associated with neurological diseases, but translation into tractable biological mechanisms is lagging. Larval zebrafish are an attractive model to investigate genetic contributions to neurological diseases. However, current CRISPR-Cas9 methods are difficult to apply to large genetic screens studying behavioural phenotypes. To facilitate rapid genetic screening, we developed a simple sequencing-free tool to validate gRNAs and a highly effective CRISPR-Cas9 method capable of converting >90% of injected embryos directly into F0 biallelic knockouts. We demonstrate that F0 knockouts reliably recapitulate complex mutant phenotypes, such as altered molecular rhythms of the circadian clock, escape responses to irritants, and multi-parameter day-night locomotor behaviours. The technique is sufficiently robust to knockout multiple genes in the same animal, for example to create the transparent triple knockout crystal fish for imaging. Our F0 knockout method cuts the experimental time from gene to behavioural phenotype in zebrafish from months to one week.
A Bayesian analysis of the association between Leukotriene A4 Hydrolase genotype and survival in tuberculous meningitis
Authors: Whitworth Laura , Coxon Jacob , van Laarhoven Arjan , Thuong Nguyen Thuy Thuong , Dian Sofiati , Alisjahbana Bachti , Ganiem Ahmad Rizal , van Crevel Reinout , Thwaites Guy E , Troll Mark , Edelstein Paul H , Sewell Roger , Ramakrishnan Lalita
Published: January 2021

Tuberculous meningitis has high mortality, linked to excessive inflammation. However, adjunctive anti-inflammatory corticosteroids reduce mortality by only 30%, suggesting that inflammatory pathophysiology causes only a subset of deaths. In Vietnam, the survival benefit of anti-inflammatory corticosteroids was most pronounced in patients with a C/T promoter variant in the leukotriene A4 hydrolase (LTA4H) gene encoding an enzyme that regulates inflammatory eicosanoids. LTA4H TT patients with increased expression had increased survival, consistent with corticosteroids benefiting individuals with hyper-inflammatory responses. However, an Indonesia study did not find an LTA4H TT genotype survival benefit. Here using Bayesian methods to analyse both studies, we find that LTA4H TT genotype confers survival benefit that begins early and continues long-term in both populations. This benefit is nullified in the most severe cases with high early mortality. LTA4H genotyping together with disease severity assessment may target glucocorticoid therapy to patients most likely to benefit from it.
Mutations in SKI in Shprintzen–Goldberg syndrome lead to attenuated TGF-β responses through SKI stabilization
Authors: Gori Ilaria , George Roger , Purkiss Andrew G , Strohbuecker Stephanie , Randall Rebecca A , Ogrodowicz Roksana , Carmignac Virginie , Faivre Laurence , Joshi Dhira , Kjær Svend , Hill Caroline S
Published: January 2021

Shprintzen–Goldberg syndrome (SGS) is a multisystemic connective tissue disorder, with considerable clinical overlap with Marfan and Loeys–Dietz syndromes. These syndromes have commonly been associated with enhanced TGF-β signaling. In SGS patients, heterozygous point mutations have been mapped to the transcriptional co-repressor SKI, which is a negative regulator of TGF-β signaling that is rapidly degraded upon ligand stimulation. The molecular consequences of these mutations, however, are not understood. Here we use a combination of structural biology, genome editing, and biochemistry to show that SGS mutations in SKI abolish its binding to phosphorylated SMAD2 and SMAD3. This results in stabilization of SKI and consequently attenuation of TGF-β responses, both in knockin cells expressing an SGS mutation and in fibroblasts from SGS patients. Thus, we reveal that SGS is associated with an attenuation of TGF-β-induced transcriptional responses, and not enhancement, which has important implications for other Marfan-related syndromes.
Por qué el cuerpo vivido no existe Traducción de Elkin Gutiérrez
Authors:   Pontificia Universidad Católica de Chile, Romano Claude
Published: January 2021

Romano, C. (2021). Por qué el cuerpo vivido no existe: Traducción de Elkin Gutiérrez. Aporía · Revista Internacional De Investigaciones Filosóficas, (20), 120-136. https://doi.org/10.7764/aporia.20.16921
Virtualización y existencia: la técnica en el ámbito general de la vida
Authors:   Pontificia Universidad Javeriana (Colombia), Velásquez Camelo Edgar Enrique
Published: January 2021

El objetivo de este artículo es presentar una reflexión acerca de la técnica en el ámbito general de la vida; en otras palabras, entender el impacto de los dispositivos tecnológicos en los múltiples escenarios vitales del ser humano en la actualidad- como hemos podido constatar con mayor fuerza en la pandemia Covid19-2020. La virtualización ha cobrado los línderos ontológicos del ser, ha modificado la comprensión del tiempo y el espacio y ha configurado una manera nueva de comprendernos en el mundo. En primer lugar, indagaremos los efectos de la virtualización en el mundo actual, para que, en segundo lugar, desde la propuesta de Heidegger en Serenidad proponer una forma loable de cultivar el pensamiento reflexivo en un mundo tecnificado. ¿La virtualización de la vida social afecta la constitución antropológica existencial del ser humano? En otras palabras ¿de qué manera afecta los procesos de virtualización digital la vida del ser humano?
Valorization of Green Clay from Bouaflé (Ivory Coast) in the Simultaneous Elimination of Organic Pollutants and Metallic Trace Elements by Adsorption: Case of Methylene Blue and Cadmium Ions
Authors: Coulibaly Bintou , Guillaume Pohan Lemeyonouin Aliou , Kambiré Ollo , Kouakou Lébé Prisca Sandrine , Goure-Doubi Hervé , Diabaté Donourou , Ouattara Lassiné
Published: January 2021

The objective of this work was to valorize the clays of Côte d'Ivoire in the treatment of wastewater. The study focused on the ability of raw clays from Bouaflé city to adsorb methylene blue and cadmium ions, in aqueous solution. The physicochemical characteristics of the clay were determined using the measurement of its specific surface area, chemical analysis and mineralogical analysis. It emerges from these characterizations that clay is essentially composed of type 2/1 minerals such as illite (32.94%), type 1/1 kaolinite (8.47%), quartz (40.23 %) and approximately iron oxy-hydroxides (18.36%). Its specific surface is 37.58 m2 / g. The kinetics, thermodynamics and isotherms of adsorption have been used to understand the mechanism of adsorption. The results obtained show that the organic pollutant alone in solution (methylene blue (MB)) is adsorbed quite quickly. We obtained a decoloration yield greater than 90% after 40 min of adsorbate-adsorbent contact. The elimination of methylene blue is greater in a basic medium. The BM adsorption kinetics were modeled. The comparison of the correlation factors of the different kinetic models used has shown that the adsorption kinetics of the organic pollutant (MB) better match the pseudo second order kinetic model. Thermodynamics predicted a spontaneous endothermic surface reaction, due to the positive sign of  and the negative sign of , obtained (  = 31.398;  = -12.635). Analysis of adsorption isotherms allowed us to show that the adsorption of methylene blue on clay is physisorption type and in monolayer. The experiments were also performed with an aqueous solution containing both methylene blue and cadmium ions. After a contact time of 120 min, 60% of the cadmium ions are adsorbed on the clay against only 20% of methylene blue. Thus, clay preferentially eliminates trace metal elements (Cd2+) compared to organic pollutants (methylene blue).
Development of Solar Operated Walking Type Power Weeder
Authors: Kachhot A. R. , Dulawat M. S. , Makavana J. M. , Dobariya U. D. , Vadher A. L.
Published: January 2021

Power weeders are most commonly used machines for removing weeds, to prevent them from competing with main crops. However, these power weeders are power by either petrol or diesel engine. With the shortage of fossil fuel, its unavailability in rural areas and for reducing emission due to burning of fossil fuel, an alternative energy powered weeder is very much required. As solar energy was very available and weeding usually carried out during daytime, hence an attempt made to develop a solar energy operated weeder for dryland. It comprised of a powering system and a blade assembly. The power source included solar photovoltaic panel, solar charge controller, battery, motor charge controller and BLDC motor. The sweep type blade was used, which is mounted behind the main frame and power was given to the rear wheels by 750 watt 48 volt BLDC motor using a chain and sprocket drive. The performance of weeder was evaluated at three different forward speed of S1, S2 and S3 is 1.0 - 1.5, 1.5 - 2.0 and 2.0 – 2.5 km/h respectively. Total weight of weeder is 88 kg and total force required to push the weeder at 2.5 km/h was 107 kg (730 watt).  Four batteries, each of size 12 V, 12 amp, powered the motor. Two solar panels were use to charge the battery, each with a power of 150 watts, and it takes 2 h to completely charge the battery while weeder is in steady state. The battery was discharge in 1.3 h in field when solar panel disconnected. With simultaneous charging and discharging of battery, this solar power system could run the weeder for 7.3 h. The developed weeder was teste in groundnut crop having 600 mm row-to-row spacing up to 30 to 40 mm depth with a field capacity of S1, S2 and S3 was 0.042, 0.059 and 0.075 ha/h. The weeding and field efficiency for S1, S2 and S3 were found to be 90.94, 84.69, 83.50% and 79.21, 83.97, 85.68% respectively. The effect of forward speed S1, S2 and S3 on Energy expenditure rate and heart rate was found to be 8.23, 9.27 and 10.34 kJ/min or 94, 98 and 50 bpm respectively. The plant damage increased with increasing forward speed of operation, Hence the developed solar operated walking type power weeder could be used successfully by the a small scale farmer for carrying out weeding operations.
Solvent‐Dependent Adsorption‐Driven Mechanism for MOFs‐Based Yolk–Shell Nanostructures
Authors: Wang Weiwei , Xu Bolong , Pan Xueting , Zhang Junfeng , Liu Huiyu
Published: January 2021

Metal‐organic frameworks (MOFs)‐based yolk–shell nanostructures have drawn enormous attention recently due to their multifunctionality. However, the regulations of the size and morphology of yolk–shell nanostructures are still limited by the unclear formation mechanism. Herein, we first demonstrated a solvent‐dependent adsorption‐driven mechanism for synthesizing yolk–shelled MOFs‐based nanostructures coated with mesoporous SiO2 shells (ZIF‐8@mSiO2) with tunable size and morphology. The selective and competitive adsorption of methanol (CH3OH) and water (H2O) on ZIF‐8 core were found to have decisive effects on inducing the morphology evolution of yolk–shell nanostructures. The obtained yolk–shelled ZIF‐8@mSiO2 nanostructures show great promise in generating acoustic cavitation effect for sonodynamic cancer therapy in vitro. We believe that this work will not only help us to design novel MOFs‐based yolk–shell nanostructures, but also promote the widespread application of MOFs materials.
Zugang zu (tBuCP)n‐Gerüsten (n=2, 4) durch P‐C‐Bindungsspaltung von Di‐tert‐butyldiphosphatetrahedran
Authors: Hierlmeier Gabriele , Wolf Robert
Published: January 2021

Die ersten gemischten Phosphatetrahedrane wurden erst vor kurzem synthetisiert, und ihre Reaktivität ist weitgehend unbekannt. Hier berichten wir über die Reaktivität von Di‐tert‐butyldiphosphatetrahedran (1), dem Dimer von tert‐Butylphosphaalkin. Mit N‐heterocyclischen Carbenkomplexen von Nickel(I) und Nickel(0) wird die selektive Aktivierung des (tBuCP)2‐Tetraeders beobachtet. Hieraus resultieren neue Verbindungen mit vielfältigen (tBuCP)n‐Gerüsten (n=2, 4). Die Umsetzung eines der Komplexe mit CO‐Gas führt zum Ladderan (tBuCP)4. Des Weiteren kann 1 durch Eliminierung von Di‐tert‐butylacetylen in der Koordinationssphäre von Nickel als Quelle für P2‐Einheiten genutzt werden.
A Universal Approach for Controllable Synthesis of n‐Specific Layered 2D Perovskite Nanoplates
Authors: Lin Jin‐Tai , Chen Deng‐Gao , Wu Cheng‐Ham , Hsu Chia‐Shuo , Chien Chia‐Ying , Chen Hao‐Ming , Chou Pi‐Tai , Chiu Ching‐Wen
Published: January 2021

2D perovskites with chemical formula A′2An−1BnX3n+1 have recently attracted considerable attention due to their tunable optical and electronic properties, which can be attained by varying the chemical composition. While high color‐purity emitting perovskite nanomaterials have been accomplished through changing the halide composition, the preparation of single‐phase, specific n‐layer 2D perovskite nanomaterials is still pending because of the fast nucleation process of nanoparticles. We demonstrate a facile, rational and efficacious approach to synthesizing single‐phase 2D perovskite nanoplates with a designated n number for both lead‐ and tin‐based perovskites through kinetic control. Casting carboxylic acid additives in the reaction medium promotes selective formation of the kinetic product—multilayer 2D perovskite—in preference to the single‐layer thermodynamic product. For the n‐specific layered 2D perovskites, decreasing the number of octahedral layers per inorganic sheet leads to an increase of photoluminescence energy, radiative decay rate, and a significant boost in photostability.
Visible‐Light‐Induced 1,3‐Aminopyridylation of [1.1.1]Propellane with N‐Aminopyridinium Salts
Authors: Shin Sanghoon , Lee Seojin , Choi Wonjun , Kim Namhoon , Hong Sungwoo
Published: January 2021

Through the formation of an electron donor–acceptor (EDA) complex, strain‐release aminopyridylation of [1.1.1]propellane with N‐aminopyridinium salts as bifunctional reagents enabled the direct installation of amino and pyridyl groups onto bicyclo[1.1.1]pentane (BCP) frameworks in the absence of an external photocatalyst. The robustness of this method to synthesize 1,3‐aminopyridylated BCPs under mild and metal‐free conditions is highlighted by the late‐stage modification of structurally complex biorelevant molecules. Moreover, the strategy was extended to P‐centered and CF3 radicals for the unprecedented incorporation of such functional groups with pyridine across the BCP core in a three‐component coupling. This practical method lays the foundation for the straightforward construction of new valuable C4‐pyridine‐functionalized BCP chemical entities, thus significantly expanding the range of accessibility of BCP‐type bioisosteres for applications in drug discovery.
A MOF‐based Ultra‐Strong Acetylene Nano‐trap for Highly Efficient C2H2/CO2 Separation
Authors: Niu Zheng , Cui Xili , Pham Tony , Verma Gaurav , Lan Pui Ching , Shan Chuan , Xing Huabin , Forrest Katherine A. , Suepaul Shanelle , Space Brian , Nafady Ayman , Al‐Enizi Abdullah M. , Ma Shengqian
Published: January 2021

Porous materials with open metal sites have been investigated to separate various gas mixtures. However, open metal sites show the limitation in the separation of some challenging gas mixtures, such as C2H2/CO2. Herein, we propose a new type of ultra‐strong C2H2 nano‐trap based on multiple binding interactions to efficiently capture C2H2 molecules and separate C2H2/CO2 mixture. The ultra‐strong acetylene nano‐trap shows a benchmark Qst of 79.1 kJ mol−1 for C2H2, a record high pure C2H2 uptake of 2.54 mmol g−1 at 1×10−2 bar, and the highest C2H2/CO2 selectivity (53.6), making it as a new benchmark material for the capture of C2H2 and the separation of C2H2/CO2. The locations of C2H2 molecules within the MOF‐based nanotrap have been visualized by the in situ single‐crystal X‐ray diffraction studies, which also identify the multiple binding sites accountable for the strong interactions with C2H2.
A General Approach for Monolayer Adsorption of High Weight Loadings of Uniform Nanocrystals on Oxide Supports
Authors: Kao Kun‐Che , Yang An‐Chih , Huang Weixin , Zhou Chengshuang , Goodman Emmett D. , Holm Alexander , Frank Curtis W. , Cargnello Matteo
Published: January 2021

Monodispersed metal and semiconductor nanocrystals have attracted great attention in fundamental and applied research due to their tunable size, morphology, and well‐defined chemical composition. Utilizing these nanocrystals in a controllable way is highly desirable especially when using them as building blocks for the preparation of nanostructured materials. Their deposition onto oxide materials provide them with wide applicability in many areas, including catalysis. However, so far deposition methods are limited and do not provide control to achieve high particle loadings. This study demonstrates a general approach for the deposition of hydrophobic ligand‐stabilized nanocrystals on hydrophilic oxide supports without ligand‐exchange. Surface functionalization of the supports with primary amine groups either using an organosilane ((3‐aminopropyl)trimethoxysilane) or bonding with aminoalcohols (3‐amino‐1,2‐propanediol) were found to significantly improve the interaction between nanocrystals and supports achieving high loadings (>10 wt. %). The bonding method with aminoalcohols guarantees the opportunity to remove the binding molecules thus allowing clean metal/oxide materials to be obtained, which is of great importance in the preparation of supported nanocrystals for heterogeneous catalysis.
Activation of Di‐tert‐butyldiphosphatetrahedrane: Access to (tBuCP)n (n=2, 4) Ligand Frameworks by P−C Bond Cleavage
Authors: Hierlmeier Gabriele , Wolf Robert
Published: January 2021

The first mixed phosphatetrahedranes were reported only recently and their reactivity is virtually unexplored. Herein, we present a reactivity study on di‐tert‐butyldiphosphatetrahedrane (1), which is the dimer of tert‐butylphosphaalkyne. The (tBuCP)2 tetrahedron is activated selectively by N‐heterocyclic carbene (NHC) nickel(I) and nickel(0) complexes, resulting in novel complexes featuring diverse (tBuCP)n‐frameworks (n=2, 4). Release of the (tBuCP)4 framework from one of the complexes was achieved by addition of CO gas. Furthermore, 1 can be used as a source for P2 units by elimination of di‐tert‐butylacetylene in the coordination sphere of nickel.
DNA Ring‐Opening Polymerization Driven by Base Stacking
Authors: Zhang Zhe , Yu Shuang , Zuo Hua
Published: January 2021

Supramolecular polymers, relying on reversible intermolecular interactions, promise a wide range of applications, including optoelectronic materials, self‐healing materials, and biomedical delivery materials. Among potential molecular candidates, DNA strands act as an excellent platform. DNA has a well‐established secondary structure (double helix), and its intermolecular interactions can be readily thermodynamically engineered and kinetically controlled. Extensive studies have demonstrated that various DNA motifs can polymerize/assemble into large polymers with different topology, geometry, and dimensionalities. Most of the reported polymerization is driven by hybridization of DNA strands. Herein, we report a novel system of DNA supramolecular polymerization that is driven by DNA base stacking. The polymerization has been confirmed by native polyacrylamide gel electrophoresis (PAGE) and atomic force microscopy (AFM). We believe that this work will expand the toolbox for DNA supramolecular polymerization and would, with further development, increase further control of DNA supramolecular polymerization.
A Robust Mesoporous Al2O3‐Based Nanocomposite Catalyst for Abundant NOx Storage with Rational Design of Pt and Ba Species
Authors: Wakabayashi Ryutaro , Tomita Atsuko , Kimura Tatsuo
Published: January 2021

The nanostructural design of heterogeneous catalysts has often been demanded for assessing synergetic effects, which should be developed further by using high‐surface‐area porous metal oxide supports. However, such opportunities have been undermined by the poor stability of ordered mesoporous structures. Herein, rational design is demonstrated to obtain nanocomposite catalysts showing improved NOx storage properties owing to the presence of Ba species over a well‐designed mesoporous alumina (Al2O3) support. It is found that Ba species are impregnated successfully only after the stabilization of the mesoporous structure by full crystallization of Al2O3 frameworks to the γ‐phase, with the formation of Pt nanoparticles coinciding with complete removal of organic components. All the insights during this synthetic procedure are essential for designing high‐performance catalysts to purify and recover NOx molecules, and are applied for designing a variety of cutting‐edge mesoporous nanocomposite catalysts.
Corporate sustainability and the market pricing of accounting numbers
Authors: Choi Hyunjung , Moon Doocheol , Guiral Andres , Choi Byungchul
Published: January 2021

This study investigates the association between CSR and the market pricing of accounting income numbers' persistence. More specifically, we examine whether the market evaluation of earnings persistence relies on the firm's CSR activities. We find that the market overestimates the persistence of earnings, leading the market to overprice the earnings for CSR companies in Korean setting. We also find that market overprices components of earnings, which are accruals and cash flow from operations, for CSR companies. However, results show that the level of CSR activities does not affect investors' rational pricing of earnings. This study suggests that market participants prefer companies engaging in CSR activities because they are more likely to provide better financial performance and earnings quality. This preference leads investors to overestimate the persistence of earnings and its components for CSR companies.
Performance analysis of an efficient linear constellation precoded generalized frequency division multiplexing with index modulation in 5G heterogeneous wireless network
Authors: Kumar Relangi Anil , Prasad K. Satya
Published: January 2021

Nowadays, wireless accesses are demanded with new applications, but they generate many technical issues. Moreover, the issues related to the beyond fifth generation (5G) wireless networks can be tackled using an orthogonal frequency division multiplexing (OFDM) schemes. Due to the huge growth of wireless users, this scheme exists with some technical challenges. An enhanced radio access technology is required to tackle the technical constraints of upcoming 5G wireless network applications. Nowadays, the generalized frequency division multiplexing (GFDM) scheme is exploited by wireless networks because of their benefits like spectral efficiency, low latency, and out‐of‐band (OOB) emission. In this paper, a linear constellation precoded GFDM with interleaved quadrature index modulation (LCP‐GFDM‐IQIM) scheme is proposed to harvest extra diversity gain by spreading the information symbols in‐phase/quadrature component. Also, in‐phase/quadrature (I and Q) dimensions are explored in index modulation (IM). Both theoretical and simulation analysis shows that the proposed LCP‐GFDM‐IQIM scheme achieves better spectral efficiency and energy efficiency as compared to the existing methods.
Experimental and DFT studies on Hexacoordinated acyl(alkyl)and Pentacooordinated Hydroxyalkyl(phosphinite)erhodium(III). Catalytic Hydrolysis of Ammonia Borane
Authors: Azpeitia Susan , Mendicute‐Fierro Claudio , Huertos Miguel A. , Rodríguez‐Diéguez Antonio , Seco José M. , Mota Antonio J. , Garralda María A.
Published: January 2021

[Rh(nbd)Cl]2(nbd=norbornadiene) reacts with quinoline‐8‐carbaldehyde (C9H6NCHO) and pyrazole (Hpz) affording, depending on Rh/Hpz ratio, acyl‐alkyl [Rh(μ‐Cl)(C9H6NCO)(Hpz)(σ‐C7H9)]2(1) or [RhCl(C9H6NCO)(Hpz)2(σ‐norbornenyl)] (2), stereoselectively as confirmed by DFT calculations. Hydrogen bond between NH‐pyrazole and O‐acyl occurs.1and2react with diphenylphosphine oxide (SPO) giving 16e [RhCl(C9H6NC(nbyl))(Ph2PO)(Hpz)] (3) through SPO κ1‐P‐coordination, C−C bond coupling between acyl and norbornenyl and outer‐sphere O(P)‐to‐O(C) hydrogen transfer.3shows distorted trigonal bipyramidal structure with weak intramolecular (C)−OH⋅⋅⋅O(=P) and NH⋅⋅⋅Cl hydrogen bonds. DFT calculations indicate this 16e structure being favoured by σ‐ and π‐type orbital multi‐overlapping between pyrazole and both the OH⋅⋅⋅O and chlorine and by intermolecular forces in the crystal. Solutions of3contain an equilibrium between trigonal bipyramid and a square‐planar pyramid with OH interacting with phosphoryl and NH, confirmed by DFT13C NMR calculations.1is very efficient homogeneous catalyst for H3N−BH3hydrolysis to release hydrogen under air.
Effects of Gouda cheese and Allium hookeri on thermogenesis in mice
Authors: Kim Yong‐An , Lee Sang‐Soo , Yoo Jayeon , Kim Eun‐Mi , Nam Myoung Soo , Kim Kee K.
Published: January 2021

Cheese contains various beneficial nutrients, including calcium and whey protein, as well as large amounts of saturated fatty acids. Thus, intake of cheese increases the production of low‐density lipoprotein‐cholesterol (LDL‐C), a well‐defined risk factor for cardiovascular disease. Therefore, identification of natural products that inhibit LDL‐C production following cheese intake and verification of the efficacy of such products in animal models are essential. Here, we evaluated the effects of Allium hookeri, a well‐known traditional herbal remedy, on metabolism and thermogenesis in mice consuming a cheese‐containing diet. Intake of A. hookeri extracts significantly blocked increases in body weight and fat mass caused by intake of Gouda cheese in mice. Additionally, increases in blood triglyceride levels following intake of Gouda cheese were alleviated by A. hookeri. Moreover, intake of Gouda cheese enhanced thermogenesis efficiency. Thus, A. hookeri may have applications as an important additive for reducing the risk of metabolic disease resulting from cheese consumption.
Multimodal imaging of a rare interventricular septum dissecting aneurysm: A case report
Authors: Zhao Li , Chen Jian , Wang Qinghui , Li Jianhua , Song Xiaolei , Ding Yunchuan
Published: January 2021

We report the case of a patient who presented with chest pain and palpitation, and in whom multimodality imaging, including transthoracic echocardiography, computer tomography angiogram, and coronary angiogram led to the diagnosis of interventricular septum dissecting aneurysm resulting from the rupture of a sinus of Valsalva aneurysm and paravalvular aortic root pseudoaneurysm. The patient underwent the modified Cabrol procedure in the cardiac surgery department. His ruptured sinus of Valsalva aneurysm was repaired and its communication with the pseudoaneurysm was closed. This case report highlights the role of multimodality cardiac imaging.
Antiretroviral therapy and Kaposi’s sarcoma trends and outcomes among adults with HIV in Latin America
Authors: Castilho Jessica L , Kim Ahra , Jenkins Cathy A , Grinsztejn Beatriz , Gotuzzo Eduardo , Fink Valeria , Padgett Denis , Belaunzaran‐Zamudio Pablo F , Crabtree‐Ramírez Brenda , Escuder Maria Mercedes , Souza Rosa Alencar , Tenore Simone B , Pimentel Sidnei R , Ikeda Maria Letícia Rodrigues , de Alencastro Paulo R , Tupinanbas Unai , Brites Carlos , Luz Estela , Netto Juliana , Cortes Claudia P , Grangeiro Alexandre , Shepherd Bryan E , McGowan Catherine C ,   the Caribbean, Central, South America network for HIV Epidemiology (CCASAnet)
Published: January 2021

Introduction

Kaposi’s sarcoma (KS) remains the most frequent malignancy in persons living with HIV (PWH) in Latin America. We examined KS trends and outcomes from Latin American clinical sites in the era of increased access to antiretroviral therapy (ART).

Methods

Cohorts in Brazil, Peru, Mexico, Honduras, Argentina and Chile contributed clinical data of PWH ≥16 years old from 2000 to 2017, excluding patients with KS diagnosed before clinic enrolment. We compared KS incidence over time using multivariable incidence rate ratios. Predictors of KS before/at or after ART initiation and of mortality after KS were examined using Cox regression.

Results

Of 25 981 PWH, 481 had incident KS, including 200 ART‐naïve and 281 ART‐treated patients. From 2000 to 2017, the incidence of KS decreased from 55.1 to 3.0 per 1000 person‐years. In models adjusting for CD4 and other factors, the relative risk for KS decreased from 2000 to 2008. Since 2010, the adjusted risk of KS increased in the periods before and ≤90 days after ART initiation but decreased >90 days after ART. In addition to low CD4 and male‐to‐male sex, KS risk after ART was associated with age and history of other AIDS‐defining illnesses. Mortality after KS (approximately 25% after five years) was not associated with either year of KS diagnosis nor timing of diagnosis relative to ART initiation.

Conclusions

KS incidence in Latin America has remained stable in recent years and risk is highest before and shortly after ART initiation. Early diagnosis of HIV and ART initiation remain critical priorities in the region.
The commonality of core biological groups across freshwater food webs
Authors: Lansac‐Tôha Fernando Miranda , Quirino Bárbara Angélio , Souza Yasmin Rodrigues , Lansac‐Tôha Fábio Amodêo , Velho Luiz Felipe Machado , Baumgartner Matheus Tenório
Published: January 2021

Assessing how organisms interact is fundamental to understand biodiversity patterns. Like many ecosystems, most freshwater environments are susceptible to spatial and temporal variations, especially floodplains. In spite of the expected variability, the structure of interactions in food webs is a paramount aspect to uncover processes related to ecosystem functioning. Here, we surveyed four large floodplains to identify the biological groups that are protagonists across different freshwater food webs. We used limnological data on physical and biochemical variables, combined with biological information on 10 communities grouped into 41 trait‐based categories. Despite the expected differences among floodplains and between hydrologic periods (dry and flood), we identified that complex freshwater food webs shared core network compartments. Using the eigenvector centrality as a measure of importance to the whole food web, we found that both primary producers (i.e., phytoplankton) and potential top predators (i.e., fish) were the core groups in freshwater trophic networks. These biological groups were consistently among the most linked compartments in all reconstructed food webs. Considering variations among food webs, we found that most differences were dictated by how compartments interact, rather than by their co‐occurrences. Perhaps equally important is that omnivory was important for the reconstructed food webs, drawing attention to this interaction type as a fundamental aspect to unveil ecosystem processes. Although more empirical research is required to fully understand the importance of biotic interactions in freshwater food webs, our findings underline that ecosystems are more likely to collapse when disturbances affect the boundaries of the energy paths.
Measuring transverse relaxation rates of the major brain metabolites from single‐voxel PRESS acquisitions at a single TE
Authors: Nosrati Reyhaneh , Balasubramanian Mukund , Mulkern Robert
Published: January 2021

Purpose

To compare transverse relaxation rates of brain metabolites estimated from single‐TE PRESS acquisitions with more conventionally derived rates estimated from multiple‐TE PRESS acquisitions.

Methods

Single‐voxel (8 mL) PRESS data within white matter from 6 subjects were acquired at five different TEs. Transverse relaxation rates R2 of N‐acetylaspartate, creatine, and choline were estimated from a single TE using full versus right‐side‐only sampling of the echo. These R2 values were compared with R2Hahn values obtained from the multiple‐TE PRESS acquisitions.

Results

Following baseline subtraction and RMS weighting, interindividual mean R2 values from TE = 288 ms magnitude spectra for choline, creatine, and N‐acetylaspartate were highly correlated with respective R2Hahn values (r2 = 0.99). Paired individual measurements at this TE showed less correlation (r2 = 0.48), primarily due to the N‐acetylaspartate resonance. Using TE = 360 ms data for N‐acetylaspartate and 288 ms for choline and creatine resulted in an improved correlation coefficient (r2 = 0.80). The average absolute intra‐individual differences in the estimated R2s between single‐TE and Hahn method was 9.6 ± 7.7%.

Conclusion

For the major brain metabolite singlets, R2Hahn values showed correlations with more fragile measurements of R2 from a single TE that are worthy of interest. Because the left side of long‐TE spin echoes is available “for free” from an acquisition perspective, and although the single‐TE method for estimating R2 values is associated with lower precision, the reduction in scan time may be clinically helpful.
Acute chest syndrome in pediatric sickle cell disease: Associations with racial composition and neighborhood deprivation
Authors: Alishlash Ammar Saadoon , Rutland Sarah B. , Friedman Annabelle J. , Hampton Jane I. , Nourani Anis , Lebensburger Jeffrey , Oates Gabriela R.
Published: January 2021

Background

Acute chest syndrome (ACS) is the leading cause of death for children with sickle cell disease (SCD). Recurrent ACS has detrimental effects on pulmonary health and health care costs. Neighborhood characteristics affect the outcomes of many pediatric chronic diseases, but their role in SCD is not well studied. In this study, we investigated the effects of area‐level socioeconomic deprivation and racial composition on the recurrence of ACS.

Study Design

We performed a retrospective cross‐sectional analysis of clinical data from a large pediatric SCD center. Patients’ residential addresses were geocoded and linked to a composite area deprivation index (ADI) and percent African American population at the level of Census block groups. The association of recurrent ACS with neighborhood characteristics was evaluated using logistic regression analysis.

Results

The sample included 709 children with SCD. Residence in a socioeconomically deprived neighborhood was associated with 27% less risk of recurrent ACS, and residence in a predominantly African American neighborhood was associated with 41% less risk of ACS recurrence. The racial composition explained the protective effect of living in a high‐deprivation area after adjusting for sociodemographic and clinical covariates. Demographic and clinical factors associated with recurrent ACS included older age, male gender, asthma, hydroxyurea use, and chronic transfusion therapy.

Conclusions

This is the first study to report a protective effect of residing in a predominantly African American community for ACS recurrence. Further prospective studies are needed to confirm the association and to understand the mechanisms of such relationship.
School and educational support programmes for paediatric oncology patients and survivors: A systematic review of evidence and recommendations for future research and practice
Authors: Burns Mary A. , Fardell Joanna E. , Wakefield Claire E. , Cohn Richard J. , Marshall Glenn M. , Lum Alistair , Ellis Sarah J. , Donnan Barb , Walwyn Thomas , Carter Amanda , Barton Belinda , Lah Suncica
Published: January 2021

Objectives

The Psychosocial Standards of Care (PSSC) in paediatric oncology prescribe the minimum standards for education support. It is unknown, however, if published education support programmes for children with cancer meet the PSSC standards for education support. Successful implementation of standards for education support is challenging but may be achieved with guidance. We aimed to (1) review education support programmes for childhood cancer patients and survivors against the PSSC standards and (2) provide practical recommendations for future research and implementation of education support programmes.

Methods

We searched PsycINFO, PubMed, CINAHL, EMBASE, and Educational Resources Information and Center databases. We reviewed the education support programmes using five evaluation criteria derived from the PSSC and summarised the structure of identified programmes. We examined the features and limitations of programmes that met all evaluation criteria.

Results

We identified 20 education support programmes in paediatric oncology, including peer programmes (n = 3), teacher programmes (n = 5), and school re‐entry programmes (SRPsn = 12). We found that three SRPs met all evaluation criteria and that SRP components were timed according to the child's position on the cancer trajectory (e.g., diagnosis and treatment, school re‐entry, and follow up throughout schooling). The supporting evidence of the programmes, however, is unclear due to the lack of adequately designed studies.

Conclusions

SRPs provide a promising structure for future education support programmes. We recommend strategies for developing and evaluating education support that adheres to the PSSC and adapts to international and local contexts.