bluuebunny/crossref_metadata_2025 huggingface dataset:
The photocatalytic mechanism of organic dithienophosphole derivatives as highly efficient photo-redox catalysts
Authors: Sun Ping-Ping , Chi Weijie , Kripalani Devesh R. , Zhou Kun
Published: August 2020

Low activation barriers and high rate constants are obtained in both activation and deactivation processes featuring DTP derivatives as highly efficient photo-redox catalysts.
Optical absorption properties of metal–organic frameworks: solid state versus molecular perspective
Authors: Fumanal Maria , Corminboeuf Clémence , Smit Berend , Tavernelli Ivano
Published: August 2020

The challenges of the description of excited states in MOF crystals are addressed by periodic and molecular computations.
Aggregation and deposition behaviors of dissolved black carbon with coexisting heavy metals in aquatic solution
Authors: Xu Yanghui , Ou Qin , Liu Caihong , Zhou Xiaojun , He Qiang , Wu Zhengsong , Huang Ruixing , Ma Jun , Lu Dongming , Huangfu Xiaoliu
Published: August 2020

Existing heavy metals promoted aggregation and deposition of dissolved black carbon, which was related to the physicochemical properties of the metal cations.
Enhanced photocatalytic reduction of Cr(vi) to Cr(iii) over g-C3N4 catalysts with Ag nanoclusters in conjunction with Cr(iii) quantification based on operando low-field NMR relaxometry
Authors: Niu Xingxing , Dong Jingxian , Wang Xue Lu , Yao Ye-Feng
Published: August 2020

Ag nanoclusters are anchored on g-C3N4 for the photocatalytic reduction of Cr(vi), and experience real-time monitoring by operando low-field NMR relaxometry via quantifying the concentration of paramagnetic Cr(iii) in solution.
Post-screening characterization of an acidic polysaccharide from Echinacea purpurea with potent anti-inflammatory properties in vivo
Authors: Li Qiu , Yang Fenfang , Hou Ranran , Huang Tingting , Hao Zhihui
Published: August 2020

We obtained three polysaccharides from Echinacea purpurea and found EPPS-3 had solid anti-inflammatory activity.
Quercetin improves gut dysbiosis in antibiotic-treated mice
Authors: Shi Tala , Bian Xiangyu , Yao Zhanxin , Wang Yawen , Gao Weina , Guo Changjiang
Published: August 2020

Diversity and activity of gut microbiota residing in humans and animals are significantly influenced by the diet. A quercetin containing diet is effective in recovering gut microbiota in mice after antibiotic treatment and may act as a prebiotic in combating gut dysbiosis.
Using iron sulphate to form both n-type and p-typepseudo-thermoelectrics: non-hazardous and ‘second life’ thermogalvanic cells
Authors: Buckingham Mark A. , Laws Kristine , Sengel Jason T. , Aldous Leigh
Published: August 2020

Conventional electrically in-series thermogalvanic cells are proven options to chemically convert waste heat into electricity, but often utilise incompatible chemicals. This work reports significantly safer and more robust cell chemistry.
In the search of active nanocarriers for delivery of mitomycin C drug
Authors: Mohajeri Afshan , Amigh Soode
Published: August 2020

The application of chitosan, poly-caprolactone, carbon nanotubes, and boron nitride nanotubes as potential nanocarriers for the delivery of mitomycin C drug is investigated.
Design, characterization, and application of elemental 2D materials for electrochemical energy storage, sensing, and catalysis
Authors: Mujib Shakir Bin , Ren Zhongkan , Mukherjee Santanu , Soares Davi Marcelo , Singh Gurpreet
Published: August 2020

Elemental 2D materials have emerged as promising candidates for electrochemical applications that require miniaturized devices and superior performance.
Novel 1,3,4-thiadiazole compounds as potential MAO-A inhibitors – design, synthesis, biological evaluation and molecular modelling
Authors: Sağlık Begüm Nurpelin , Kaya Çavuşoğlu Betül , Acar Çevik Ulviye , Osmaniye Derya , Levent Serkan , Özkay Yusuf , Kaplancıklı Zafer Asım
Published: August 2020

Compound 6b is a reversible and competitive hMAO-A inhibitor.
Proposed mechanical method for switching the spin transport channel in two-dimensional magnetic metal–magnetic semiconductor van der Waals contacts
Authors: Gao Pengfei , Li Xingxing , Yang Jinlong
Published: August 2020

Controlling the spin transport across two-dimensional magnetic metal–magnetic semiconductor contacts via mechanically regulating the interfacial magnetic coupling.
Modulating the electro-optical properties of doped C3N monolayers and graphene bilayers via mechanical strain and pressure
Authors: Bafekry A. , Nguyen C. , Obeid M. M. , Ghergherehchi M.
Published: August 2020

The effect of atomic doping on the electronic properties of C3N monolayer and graphene bilayer is investigated. We found that doped C3N monolayer and doped graphene bilayer are a direct semiconductor. Our result show that the electronic properties of the studied structures can be modulated by electric field and mechanical strain.
Modular design of Bi-specific nanoplatform engaged in malignant lymphoma immunotherapy
Authors: Bai Chen , Hu Pengcheng , Zhang Wei , Song Lina , Liu Di , Chen Yi , Ma Ming , Gu Ning , Zhang Yu
Published: August 2020

The bi-specific nanoplatform (BSNP) composed of Fe3O4 nanoparticles and CD20 and CD3 antibodies, was synthesized via modular designed method. BSNP can induce direct apoptosis of Raji cell and T cell-mediated Raji cell lysis, respectively.
Multi-functional photoelectric sensors based on a series of isopolymolybdate-based compounds for detecting different ions
Authors: Wang Chen , Ying Jun , Mou Hai-chen , Tian Ai-xiang , Wang Xiu-li
Published: August 2020

Five molybdate-based compounds can be used as multi-functional photoelectric sensors. They act as electrochemical sensors for sensing NO2− and Cr(vi). Compound 3 also can be used as a fluorescent sensor for detecting Hg2+.
Effective demulsification for oil–water separation through metal–organic frameworks with an amphipathic micro-domain
Authors: Wang Rui , Feng Yi , Xu Haijuan , Zou Yanzhao , Fan Leiyi , Zhang Ruiyang , Zhou Ying
Published: August 2020

MIL-100(Fe), a metal organic framework (MOF), is an intrinsic heterogeneous demulsifier which can demulsify O/W and W/O emulsions effectively and resist the negative effects of pH and salinity as well as the degradation of the surfactant.
Fusion of aggregation-induced emission and photochromics for promising photoresponsive smart materials
Authors: Yan Qing , Wang Sheng
Published: August 2020

This review summarizes the recent progresses made in AIE-active photochromic materials with respect to molecular structures, material morphology, and practical applications.
Boosting the ionic conductivity of PEO electrolytes by waste eggshell-derived fillers for high-performance solid lithium/sodium batteries
Authors: Xu Laiqiang , Li Jiayang , Deng Wentao , Li Lin , Zou Guoqiang , Hou Hongshuai , Huang Lanping , Ji Xiaobo
Published: August 2020

Poly(ethylene oxide) (PEO)-based polymer electrolytes are extensively investigated, and they have rapidly developed in all-solid-state batteries (ASSBs) over recent years for their good interface contact with electrodes, easy shaping and decent flexibility.
Effect of substituents and promoters on the Diels–Alder cycloaddition reaction in the biorenewable synthesis of trimellitic acid
Authors: Khan Tuhin Suvra , Gupta Shelaka , Ahmad Maaz , Alam Md Imteyaz , Haider M. Ali
Published: August 2020

Production of biobased trimellitic acid via Diels–Alder cycloaddition reaction.
Effect of bimodal mesoporous carbon as PtRu catalyst support for direct methanol fuel cells
Authors: Montiel Gonzalo , Fuentes-Quezada Eduardo , Bruno Mariano M. , Corti Horacio R. , Viva Federico A.
Published: August 2020

A porous carbon with different pore sizes was synthesized and employed as support for PtRu nanoparticles.
In situ formation of Fe3O4/N-doped carbon coating on the surface of carbon fiber with improved electromagnetic wave-absorption property
Authors: Sun Qilong , Ji Yue , He LiFen , Long Xiaoyun
Published: August 2020

Carbon fiber is an absorbing material with high strength, acid and alkali resistance, high temperature resistance, flexibility, and processability and plays an important role in the electromagnetic (EM) wave absorption of civil buildings and military equipment.
Probing intrinsic dynamics and conformational transition of HIV gp120 by molecular dynamics simulation
Authors: Li Yi , Zhang Xiao-Ling , Yuan Xue , Hou Jiang-Chun , Sang Peng , Yang Li-Quan
Published: August 2020

The HIV envelope glycoprotein gp120 has evolved two distinct conformational states to balance viral infection and immune escape.
Recent developments in the chemistry of non-trigonal pnictogen pincer compounds: from bonding to catalysis
Authors: Abbenseth Josh , Goicoechea Jose M.
Published: August 2020

Pnictogen pincer complexes exhibit unique electronic structures which allow activation of a range of E–H bonds and carbon nucleophiles.
Recent advances in AFM-based biological characterization and applications at multiple levels
Authors: Liang Wenfeng , Shi Haohao , Yang Xieliu , Wang Junhai , Yang Wenguang , Zhang Hemin , Liu Lianqing
Published: August 2020

Atomic force microscopy (AFM) has found a wide range of bio-applications in the past few decades due to its ability to measure biological samples in natural environments at a high spatial resolution.
Stimuli-responsive functional materials for soft robotics
Authors: Shen Zequn , Chen Feifei , Zhu Xiangyang , Yong Ken-Tye , Gu Guoying
Published: August 2020

This review provides an overview of stimuli-responsive functional materials and their applications in soft robotics.
Withdrawn: Lipid nanoparticles co-loaded with miRNA-22 and methotrexate for enhanced anti-inflammatory response in rheumatoid arthritis
Authors: Yuan Hao , Peng Ya-Meng , Long Zhen-Yi , Wu Si-Xian , Zhou Yi-Feng
Published: August 2020

The Accepted Manuscript version of this article (published on 18 August 2020) was withdrawn on 3 December 2020 due to concerns over data validity.
Eicosanoids
Authors: Calder Philip C.
Published: August 2020

This article describes the pathways of eicosanoid synthesis, eicosanoid receptors, the action of eicosanoids in different physiological systems, the roles of eicosanoids in selected diseases, and the major inhibitors of eicosanoid synthesis and action. Eicosanoids are oxidised derivatives of 20-carbon polyunsaturated fatty acids (PUFAs) formed by the cyclooxygenase (COX), lipoxygenase (LOX) and cytochrome P450 (cytP450) pathways. Arachidonic acid (ARA) is the usual substrate for eicosanoid synthesis. The COX pathways form prostaglandins (PGs) and thromboxanes (TXs), the LOX pathways form leukotrienes (LTs) and lipoxins (LXs), and the cytP450 pathways form various epoxy, hydroxy and dihydroxy derivatives. Eicosanoids are highly bioactive acting on many cell types through cell membrane G-protein coupled receptors, although some eicosanoids are also ligands for nuclear receptors. Because they are rapidly catabolised, eicosanoids mainly act locally to the site of their production. Many eicosanoids have multiple, sometimes pleiotropic, effects on inflammation and immunity. The most widely studied is PGE2. Many eicosanoids have roles in the regulation of the vascular, renal, gastrointestinal and female reproductive systems. Despite their vital role in physiology, eicosanoids are often associated with disease, including inflammatory disease and cancer. Inhibitors have been developed that interfere with the synthesis or action of various eicosanoids and some of these are used in disease treatment, especially for inflammation.
Lyso-glycosphingolipids: presence and consequences
Authors: van Eijk Marco , Ferraz Maria J. , Boot Rolf G. , Aerts Johannes M.F.G.
Published: August 2020

Lyso-glycosphingolipids are generated in excess in glycosphingolipid storage disorders. In the course of these pathologies glycosylated sphingolipid species accumulate within lysosomes due to flaws in the respective lipid degrading machinery. Deacylation of accumulating glycosphingolipids drives the formation of lyso-glycosphingolipids. In lysosomal storage diseases such as Gaucher Disease, Fabry Disease, Krabbe disease, GM1 -and GM2 gangliosidosis, Niemann Pick type C and Metachromatic leukodystrophy massive intra-lysosomal glycosphingolipid accumulation occurs. The lysosomal enzyme acid ceramidase generates the deacylated lyso-glycosphingolipid species. This review discusses how the various lyso-glycosphingolipids are synthesized, how they may contribute to abnormal immunity in glycosphingolipid storing lysosomal diseases and what therapeutic opportunities exist.
Language and Speech Markers of Primary Progressive Aphasia: A Systematic Review
Authors: Stalpaert Jara , Cocquyt Elissa-Marie , Criel Yana , Segers Lieselot , Miatton Marijke , Van Langenhove Tim , van Mierlo Pieter , De Letter Miet
Published: August 2020

Purpose

This systematic review aimed to establish language and speech markers to support the clinical diagnosis of primary progressive aphasia (PPA) and its clinical phenotypes. Our first objective was to identify behavioral language and speech markers of early-stage PPA. Our second objective was to identify the electrophysiological correlates of the language and speech characteristics in PPA.

Method

The databases MEDLINE, Web of Science, and Embase were searched for relevant articles. To identify behavioral markers, the initial subjective complaints and the language and speech deficits detected during the initial diagnostic evaluation were summarized for PPA in general and each clinical variant according to the 2011 consensus diagnostic criteria (nonfluent variant [NFV], semantic variant, and logopenic variant [LV]). To identify electrophysiological markers, the studies in which event-related potentials (ERPs) were elicited by a language or speech paradigm in patients with PPA were included.

Results

In total, 114 relevant studies were identified, including 110 behavioral studies and only four electrophysiological studies. This review suggests that patients with the semantic variant could be accurately differentiated from the NFV and LV in the initial stages based on the consensus criteria. Nonetheless, the early differentiation between the NFV and LV is not straightforward. In the four electrophysiological studies, differences in the latency, amplitude, and topographical distribution of the semantic N400 component were found between patients with PPA and healthy controls.

Conclusions

To accurately differentiate the NFV from the LV, it could be important to assess the language and speech degeneration by more specific assessments and by more objective diagnostic methods that offer insights into the language-related processes. Electrophysiological markers of PPA were not identified in this review due to the low number of studies that investigated language-related ERPs. More controlled ERP studies in larger patient cohorts are needed to investigate the diagnostic applicability of language-related ERPs in PPA.

Supplemental Material

https://doi.org/10.23641/asha.12798080
The anisotropic optical properties of different polytypes (ε,β,δ,γ) of GaSe lamellar materials
Authors: Al-Hattab Mohamed , Moudou Lhoucine , Chrafih Younes , Khenfouch Mohammed , Bajjou Omar , Rahmani Khalid
Published: August 2020

In this paper, we have calculated the optical properties of the different polytypes of GaSe lamellar materials. The calculations are based on the DFT method and is performed using the CASTEP code. All optical properties have been studied in a domain that extends energetically from 10 meV to 35 eV and have been measured for a polarization // and ⊥ with thecaxis. A strong anisotropic was observed, which indicates that the optical properties of the GaSe material are essentially determined by the symmetry of a single layer, exactly by the symmetry resulting from the stacking of the layers. Moreover, the absorption starts in the UV–vis spectral range, the peaks appear in the UV range. The refractive index values arenxx = 2.54, 2.55, 2.88, 10.85,nzz = 3.90, 3.90, 3.26, 11.73 forε,β,γ,δ, respectively at zero photon energy. Furthermore, we notice that the optical properties of different polytypes (ε,β,δ,γ) of GaSe lamellar materials are obtained both in the ultraviolet field or in the visible domain are significant and give a strong argument for the use of these materials in various applications, namely photovoltaic cells, nanoelectronic, optoelectronic, optical fiber and photo-catalytic applications.
Numerical design of thorium and uranium fuel samples irradiation in lead environment
Authors: Oettingen Mikolaj
Published: August 2020

The paper shows capabilities of thorium-lead fuel assembly for design of irradiation experiments on ThO2 and natural UO2 fuel samples using radioisotope neutron source. The main purpose of the current analysis was to determine the irradiation environment in the samples, especially: neutron spectrum, power, activity, reaction rates, production of 233Pa and 239Np as well as breeding of 233U and 239Pu. An advanced three-dimensional numerical model for Monte Carlo radiation transport and burnup simulations was developed using the Monte Carlo Continuous Energy Burnup Code (MCB). The versatility of the assembly gives a perfect opportunity to perform many irradiation experiments for R&D on the thorium and uranium fuel cycle in a different material and geometrical environments.
Nervus vagus: Verlauf und Zuständigkeiten
Authors: Corts Magga
Published: August 2020

Der Nervus (N.) vagus ist der längste Hirnnerv und hat das ausgedehnteste Innervationsgebiet aller Hirnnerven. Er ist der einzige parasympathische Nerv, der vom Kopf zum Thorax bis zu den Bauchorganen verläuft. Zu den Kerngebieten des N. vagus gehören fünf Nervenkerne.
Prüfungsthema: Vegetatives Nervensystem
Authors: Schmid Eva C.
Published: August 2020

In diesem HPA-Prüfungstrainer beschäftigen sich alle Fragen mit dem vegetativen Nervensystem.
Vegetative Dystonie
Authors: Stern Cornelia , Vigl Sebastian , Ahl Anja M. , Heyny Rosemarie
Published: August 2020

Vier Experten stellen die Behandlung von vegetativer Dystonie mithilfe von Spagyrik, Phytotherapie, Aromatherapie und TCM vor.
Vagus auf Grün oder Rot?
Authors: Konwiarz Dieter
Published: August 2020

Der Neurophysiologe Stephen W. Porges räumte mit dem Mythos des Wohlfühlnervs auf: Nach seiner Polyvagal-Theorie vermittelt der Nervus vagus nicht nur Entspannung, sondern auch Schockstarre. Die Differenzierung zwischen ventraler (Ruhefunktionen) und dorsaler (Erstarrung) Vagusaktivität eröffnet neue Sichten auf Selbstregulation und Traumatherapie. Moderne Methoden der Polyvagal-Therapie wurden unter anderem von der Traumatherapeutin Deb Dana und dem Craniosacraltherapeuten Stanley Rosenberg entwickelt und haben sich insbesondere im Rahmen der Traumatherapie bewährt.
Der Moment als Ziel
Authors: Krudup Karin , Känner Sylke
Published: August 2020

MBSR (Mindfulness-based Stress Reduction) dient zur Stressreduktion durch Achtsamkeitstraining, das in einem achtwöchigen Kurs vermittelt wird. Ein MBSR-Kurs setzt sich vor allem aus drei formalen Übungen, informellen Übungen für den Alltag und Psychoedukation zusammen. Zentral in einem MBSR-Kurs ist, das gegenwärtige Erleben gemeinsam zu erforschen, Erfahrungen zu teilen und die gemeinsame Menschlichkeit zu erkennen.
Verdauung neu lernen
Authors: Grafen Keren
Published: August 2020

Das enterische Nervensystem (ENS) steuert die Motilität, Sekretion, Versorgung und Abwehr des Darmes und ist mit 150 Millionen Neuronen die größte Ansammlung von Nervenzellen außerhalb des Zentralnervensystems. Zu den ENS-assoziierten gastrointestinalen Störungen zählen Morbus Hirschsprung, Achalasie, die Chagas-Krankheit und als Leiterkrankung das Reizdarmsyndrom. Am Beispiel des Reizdarmsyndroms lässt sich die effektive Therapie von ENS-Störungen in Form einer Kombination aus Ernährungsumstellung, Stressreduktion und orthomolekularer Versorgung zeigen.
Synthesis of Quinoxalin-2(1H)-ones and Hexahydroquinoxalin-2(1H)-ones via Oxidative Amidation–Heterocycloannulation
Authors: Tadiparthi Krishnaji , Kumar U. K. Syam , Raghunadh Akula , Meruva Suresh Babu , Murthy V. Narayana , Rao L. Vaikunta
Published: August 2020

A metal-catalyst-free synthesis of substituted quinoxalin-2-ones from 2,2-dibromo-1-arylethanone by employing an oxidative amidation–heterocycloannulation protocol is reported. The substrate scope of the reaction has been demonstrated and a possible mechanism for this reaction has also been proposed.
Magnetic field sweep rate influence on the critical current capabilities of a Fe(Se,Te) crystal
Authors: Galluzzi A. , Buchkov K. , Nazarova E. , Tomov V. , Leo A. , Grimaldi G. , Pace S. , Polichetti M.
Published: August 2020

The relaxation phenomena of a FeSe0.5Te0.5 single crystal sample, with twinned morphology, exhibiting a second magnetization peak effect have been analyzed by means of dc magnetization measurements as a function of magnetic field (H). Using different magnetic field sweep rates for performing the superconducting hysteresis loops m(H), a change in the width of these curves has been observed together with a shift of the second peak field position. A consequent and significant variation of critical current density Jc has been extracted from the superconducting m(H) curves within the Bean critical state model. In this framework, the ratio between the critical current densities Jc calculated at 200 Oe/s and 5 Oe/s has been calculated showing interesting results in terms of transport capabilities. From the Jc(H) curves at T = 10 K for different sweep rates, the irreversibility field has been obtained for T = 10 K and fitted with a power law. The increasing trend of the irreversibility field as a function of sweep rate could suggest the use of this material for power applications where overheating due to vortices movement inside the superconductor has to be limited.
Piezotronic effect on Rashba spin–orbit coupling based on MAPbI3/ZnO heterostructures
Authors: Zhu Laipan , Wang Zhong Lin
Published: August 2020

Rashba spin–orbit coupling (SOC) is a core issue in semiconductor spintronics, which allows the manipulation of electron spin through an electric field rather than an external magnetic field, revealing a bright prospect for advanced electronic devices with ultra-high speed and integration. Conversely, the emerging piezotronic effect is the born characteristic for many semiconductors that have a non-central symmetric structure, such as ZnO and GaN. Here, we design three heterostructure devices, based on piezoelectric p-type (CH3NH3)PbI3 single crystals and n-type wurtzite-structured ZnO thin films, to theoretically study how the piezotronic effect can effectively work on the Rashba spin–orbit coupling. Benefiting from large piezoelectric charges at the interface when a vertical strain is applied, a high concentration of two-dimensional electron gas is induced in the plane of the heterostructure, which can tune the built-in electric field at the interface and further manipulate the Rashba SOC. With the increase in pressure, both the Rashba parameter and spin splitting are found to first vanish and then increase linearly for ZnO with doping densities of 1015 and 1016 cm−3. This work provides insight for manipulating electron spins via the introduction of piezocharges, showing great application potential of the piezotronic effect in tuning spintronic devices.
Collisional gyrokinetics teases the existence of metriplectic reduction
Authors: Hirvijoki Eero , Burby Joshua W.
Published: August 2020

In purely non-dissipative systems, Lagrangian and Hamiltonian reduction have been proven to be powerful tools for deriving physical models with exact conservation laws. We have discovered a hint that an analogous reduction method exists also for dissipative systems that respect the first and second laws of thermodynamics. In this paper, we show that modern electrostatic gyrokinetics, a reduced plasma turbulence model, exhibits a serendipitous metriplectic structure. Metriplectic dynamics, in general, is a well developed formalism for extending the concept of Poisson brackets to dissipative systems. Better yet, our discovery enables an intuitive particle-in-cell discretization of the collision operator that also satisfies the first and second laws of thermodynamics. These results suggest that collisional gyrokinetics, and other dissipative physical models that obey the laws of thermodynamics, could be obtained using an as-yet undiscovered metriplectic reduction theory and that numerical methods could benefit from such theory significantly. Once uncovered, the theory would generalize Lagrangian and Hamiltonian reduction in a substantial manner.
Full-quantum descriptions of molecular systems from constrained nuclear–electronic orbital density functional theory
Authors: Xu Xi , Yang Yang
Published: August 2020

We develop a full-quantum formulation of constrained nuclear–electronic orbital density functional theory (cNEO-DFT). This formulation deviates from the conventional Born–Oppenheimer framework, and all nuclei and electrons are treated on an equal footing within the molecular orbital picture. Compared to the conventional DFT, the ground state energy in full-quantum cNEO-DFT inherently includes all vibrational zero-point energies. We also derived and implemented the analytic gradient of the full-quantum cNEO-DFT energy with respect to the quantum nuclear expectation positions. With the analytic gradient, the geometry optimizations are performed, which naturally include the nuclear quantum effects and describe the geometric isotope effects. The full-quantum cNEO-DFT is tested on a series of small molecules and the transition states of two hydrogen transfer reactions. The results are compared with those from conventional DFT, DFT-VPT2, and NEO-DFT with only key protons treated quantum mechanically. It is found that the nuclear quantum effects have notable impacts on molecular equilibrium geometries and transition state geometries. The full-quantum cNEO-DFT can be a promising method for describing the nuclear quantum effects in many chemical processes.
Thermal resistance of an interfacial molecular layer by first-principles molecular dynamics
Authors: Duong Thuy-Quynh , Massobrio Carlo , Ori Guido , Boero Mauro , Martin Evelyne
Published: August 2020

The approach-to-equilibrium molecular dynamics (AEMD) methodology is applied in combination with first-principles molecular dynamics to investigate the thermal transfer between two silicon blocks connected by a molecular layer. Our configuration consists of alkanes molecules strongly coupled to the silicon surfaces via covalent bonds. In phase 1 of AEMD, the two Si blocks are thermalized at high and low temperatures to form the hot and cold reservoirs. During phase 2 of AEMD, a transfer between reservoirs occurs until thermal equilibrium is reached. The transfer across the interface dominates the transient over heat conduction within the reservoirs. The value of the thermal interface conductance is in agreement with the experimental data obtained for analogous bonding cases between molecules and reservoirs. The dependence on the length of the thermal interface resistance features two contributions. One is constant (the resistance at the silicon/molecule interface), while the other varies linearly with the length of the molecular chains (diffusive transport). The corresponding value of the thermal conductivity agrees well with experiments.
Composition dependent mobility and bandgaps in (La0.05BaxSr0.95−x)SnO3 epitaxial films
Authors: Li Kaifeng , Gao Qiang , Zhao Li , Lv Kai , Yin Lichang , Liu Qinzhuang
Published: August 2020

Perovskite stannates ASnO3 (A = Ba, Sr) as transparent conducting oxides have recently attracted much attention due to their high electron mobility and high optical transparency. Here, we investigated experimentally and theoretically the composition-dependent structural, electrical, and optical properties of (La0.05BaxSr0.95−x)SnO3 (LBSSO, x = 0–0.95) thin films. Detailed x-ray diffraction characterization studies show that the LBSSO films were epitaxially grown on the LaAlO3(001) substrates. The out-of-plane lattice constants of the LBSSO films increase from 4.045 to 4.122 Å with incorporation of the Ba content from 0 up to 0.95 in the films. The electron mobility values of the films increase gradually from 22.2 to 34.4 cm2/V s with the increasing Ba contents. The direct/indirect optical bandgaps decrease monotonously from 4.64/4.04 to 4.05/3.40 eV upon changing the Ba content from 0 to 0.95. Density functional theory calculations indicated that the Ba substitution can reduce the electron effective mass and the bandgaps, leading to a higher carrier mobility.
Data-driven kinetic energy density fitting for orbital-free DFT: Linear vs Gaussian process regression
Authors: Manzhos Sergei , Golub Pavlo
Published: August 2020

We study the dependence of kinetic energy densities (KEDs) on density-dependent variables that have been suggested in previous works on kinetic energy functionals for orbital-free density functional theory. We focus on the role of data distribution and on data and regressor selection. We compare unweighted and weighted linear and Gaussian process regressions of KEDs for light metals and a semiconductor. We find that good quality linear regression resulting in good energy–volume dependence is possible over density-dependent variables suggested in previous literature studies. This is achieved with weighted fitting based on the KED histogram. With Gaussian process regressions, excellent KED fit quality well exceeding that of linear regressions is obtained as well as a good energy–volume dependence, which was somewhat better than that of best linear regressions. We find that while the use of the effective potential as a descriptor improves linear KED fitting, it does not improve the quality of the energy–volume dependence with linear regressions but substantially improves it with Gaussian process regression. Gaussian process regression is also able to perform well without data weighting.
Quasilinear modeling of heat flux from microtearing turbulence
Authors: Xie T. , Pueschel M. J. , Hatch D. R.
Published: August 2020

Microtearing (MT) turbulence affects plasma confinement and profile evolution in many different magnetic-confinement scenarios, ranging from tokamak core plasmas to the H-mode pedestal and from spherical tokamaks to reversed-field pinches. Thus, an urgent need exists to design and test reduced models of MT turbulence and transport. Here, a heuristic quasilinear model is composed and verified by comparing its predictions against nonlinear MT simulations. It is found to yield good predictions of magnetic flutter transport as key parameters are varied: the collision frequency, the electron temperature gradient, and the normalized plasma pressure.
Methodological aspects and impact on grain weight of source reduction through shade meshes during grain filling of bread wheat
Authors: Maydup Maria L. , Antonietta Mariana , Rouillet Nicolás , Cano Maria G. , Guiamet Juan J. , Tambussi Eduardo A.
Published: August 2020

In crop studies, shading is a common approach for reducing source activity (i.e. assimilates produced by photosynthesis); however, if source reduction is not directly proportional to the degree of light attenuation, estimations could be flawed. We analysed the effects of shading at three levels on light transmittance, air and canopy temperatures, and actual photosynthetic activity at different times of day, and on grain weight in a modern genotype of bread wheat (Triticum aestivum L.). The treatments were imposed 10 days after anthesis and comprised three levels of shading with meshes: 80%, 50% and 10% transmittance during midday. The decrease in midday photosynthetic activity (electron transport rate, ETR; and CO2 assimilation, An) in the shading treatments compared with control plants did not fit a 1:1 relationship with light transmittance of the meshes; for example, the reduction in ETR and An was <50% under the mesh with 50% light transmittance. The decrease in light transmittance and photosynthesis caused by the meshes was higher during the morning and afternoon than midday. In the grain-filling period, midday ETR showed a progressive, age-dependent decrease in control plants compared with shading treatments. Initial differences in photosynthetic activity between treatments were attenuated throughout the grain-filling period. The diurnal course of air temperature showed a progressive decrease from control to shade treatments, mainly during midday. This pattern was confirmed by infrared thermometry of canopy temperature, with severe shade showing the lowest temperature. Greenness measurements at 19 days after anthesis showed delayed senescence in shaded plants, possibly due to the decrease in temperature under shade. Grain weight per ear was reduced in shading treatments (mainly with 50% and 10% light transmittance). The decrease in grain weight per ear plotted against the decrease in photosynthesis (evaluated through ETR or An) did not fit a 1:1 relationship. This could be explained in part by an observed increase in dry matter retranslocation from the stem. In summary, estimations of source reduction on the basis of light attenuation could be biased, because the photosynthesis decrease is less than proportional, and photosynthesis differences are attenuated throughout grain filling.
A novel polymorphism in the 5′ UTR of HvDEP1 is associated with grain length and 1000-grain weight in barley (Hordeum vulgare)
Authors: Watt Calum , Zhou Gaofeng , Angessa Tefera Tolera , Moody David , Li Chengdao
Published: August 2020

The gene HvDEP1, on barley (Hordeum vulgare L.) chromosome 5H, encodes a γ-subunit of the heterotrimeric G-protein complex and was previously determined to be a candidate gene underlying a major quantitative trait locus for grain length. In the present study, we identified a 9 bp indel (insertion–deletion mutation) at position –84 bp from the start codon within a reported upstream open reading frame located in the 5′ UTR (untranslated region) and developed a diagnostic molecular marker. We also identified a 13 bp indel (–514 bp) in linkage disequilibrium that bridges an important regulatory motif. Using a doubled-haploid population and a barley diversity panel, we were able to show that the effects of these indels were environmentally stable and consistently delineated phenotypic groups based on grain length and 1000-grain weight. Genotypes represented by deletions at these two positions relative to the reference cv. Morex had consistently shorter grains, by 3.69–3.96%, and lower 1000-grain weight, by 2.38–4.21%, in a doubled-haploid population studied. Additionally, a diversity panel was tested but consistent differences were observed only for grain length, reinforcing literature indicating the importance of this gene for grain-length regulation. The frequency of the longer and heavier grained reference allele was higher in modern cultivars, suggesting that indirect selection for longer grain may have occurred through direct selection for grain yield via grain-weight improvement. These results indicate that grain length and 1000-grain weight in barley can be manipulated by targeting variation in gene promoters through marker-assisted selection.
The SARS-CoV-2 ‘perfect storm’: from humble betacoronavirus to global pandemic
Authors: Howard-Jones Annaleise R , Kok Jen
Published: August 2020

The novel betacoronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused a global pandemic unprecedented in modern times. Understanding the key features that have enabled this virus to propagate so widely in the global community is critical to current and future clinical and public health efforts. High proportions of mild disease and peak viral loads at, and likely prior to, symptom onset have hindered efforts to identify and isolate infected persons effectively, facilitating undetected spread of the virus. In countries with limited diagnostic and/or contact tracing capabilities, population-wide transmission escalated beyond a critical threshold, challenging even well-developed healthcare systems. This ‘perfect storm’ for transmissibility has led to widespread outbreaks and deaths in many regions around the world. Extensive testing and contact tracing, together with Australia’s geographic advantage, tightening of international travel restrictions, physical distancing and public health messaging measures, have contributed to limiting the extent of coronavirus disease 2019 (COVID-19) spread in the country, but recent case escalation in Victoria highlights the country’s vulnerability to future outbreaks due to low population immunity.
Deconstructing bias in social preferences reveals groupy and not-groupy behavior
Authors: Kranton Rachel , Pease Matthew , Sanders Seth , Huettel Scott
Published: August 2020

Significance

Group divisions are a continual feature of human history. Using methods from experimental and behavioral economics, this study deconstructs the typical in-group bias in allocation decisions and social preferences by considering bias at the individual level. The results reveal stable individual predilections to engage in group-related discrimination, such that the same individuals who show in-group bias in a political setting also show in-group bias in a highly simplified social context. The findings point to a role for individual “groupiness” in understanding social divisions.
Defined microbiota transplant restores Th17/RORγt+regulatory T cell balance in mice colonized with inflammatory bowel disease microbiotas
Authors: Britton Graham J. , Contijoch Eduardo J. , Spindler Matthew P. , Aggarwala Varun , Dogan Belgin , Bongers Gerold , San Mateo Lani , Baltus Andrew , Das Anuk , Gevers Dirk , Borody Thomas J. , Kaakoush Nadeem O. , Kamm Michael A. , Mitchell Hazel , Paramsothy Sudarshan , Clemente Jose C. , Colombel Jean-Frederic , Simpson Kenneth W. , Dubinsky Marla C. , Grinspan Ari , Faith Jeremiah J.
Published: August 2020

Significance

Composition of gut microbiota is altered in many human diseases, including inflammatory bowel disease. Some hope that restoring microbiota to a healthy state could help treat such diseases. We have used mice colonized with microbiotas from humans with inflammatory bowel disease to study what happens when these mice receive a microbiota transplant from a set of healthy humans. We find that the mouse gut immune system is changed by microbiota transplants, becoming broadly less inflammatory and protecting mice from colitis. By culturing bacteria from these microbiotas, we identify one strain that induces inflammatory responses in mice and show that it is modified by microbiota transplant. We also show that increases in the density of microbiota following transplant may be antiinflammatory.
A method for scoring the cell type-specific impacts of noncoding variants in personal genomes
Authors: Li Wenran , Duren Zhana , Jiang Rui , Wong Wing Hung
Published: August 2020

Significance

Here we use the expression and accessibility data from a diverse set of cell types to learn a model for the dependence of the accessibility of a regulatory element on its DNA sequence and TF expression. Using GTEx samples with WGS data, we show that the noncoding variants predicted to affect accessibility are more strongly associated with the expression of nearby genes. To interpret a personal genome, we combine the sequence information with context-specific TF expression to prioritize variants and regulatory elements in any genomic region of interest. This approach should be helpful in the study of risk loci previously identified by GWAS. Results from analysis of height and WGS data from the GTEx project support this hypothesis.
Compression stiffening of fibrous networks with stiff inclusions
Authors: Shivers Jordan L. , Feng Jingchen , van Oosten Anne S. G. , Levine Herbert , Janmey Paul A. , MacKintosh Fred C.
Published: August 2020

Significance

Fat, brain, and liver tissue stiffen when squished. Although tissues are complex materials consisting of deformable, active cells within a biopolymer matrix, recent work has shown that a simple tissue analogue constructed from stiff, inert colloidal particles embedded in a reconstituted biopolymer network exhibits similar compression-stiffening behavior. Here, we show via simulations that compressing a material composed of stiff particles embedded within a fibrous network induces inhomogeneous particle displacement which, in turn, drives stretching of the interstitial network and macroscopic stiffening of the composite. We generate predictive phase diagrams for compression stiffening in 2D and 3D systems as a function of particle volume fraction and network critical strain and explore its relationship to contact percolation and jamming.
mRNA adenosine methylase (MTA) deposits m
6
A on pri-miRNAs to modulate miRNA biogenesis in
Arabidopsis thaliana
Authors: Bhat Susheel Sagar , Bielewicz Dawid , Gulanicz Tomasz , Bodi Zsuzsanna , Yu Xiang , Anderson Stephen J. , Szewc Lukasz , Bajczyk Mateusz , Dolata Jakub , Grzelak Natalia , Smolinski Dariusz J. , Gregory Brian D. , Fray Rupert G. , Jarmolowski Artur , Szweykowska-Kulinska Zofia
Published: August 2020

Significance

Recently
N
6
-methyladenosine (m
6
A) methylation has emerged as a biological process with significant impact on cellular functions. However, almost all the research regarding m
6
A methylation has been based on mRNAs. In our research, we focus on how m
6
A methylation affects microRNA (miRNA) biogenesis in
Arabidopsis
. In brief, we show that m
6
A methylation is necessary to maintain proper levels of mature miRNAs as well as their precursors. m
6
A mark affects pri-miRNA secondary structures and affects the recruitment of the Microprocessor to pri-miRNAs. We also demonstrate the interactions of MTA (m
6
A writer) with other proteins involved in miRNA biogenesis, namely RNA Polymerase II and TOUGH. Our study provides evidence of the role played by m
6
A in plant miRNA biogenesis.
Talin folding as the tuning fork of cellular mechanotransduction
Authors: Tapia-Rojo Rafael , Alonso-Caballero Álvaro , Fernández Julio M.
Published: August 2020

Significance

Talin is an adaptor protein that transduces mechanical signals into biochemical cues by recruiting a network of protein ligands in a force-dependent way. These force cues have a complex nature, oscillate in time with different frequency components, and are often embedded in noise. However, most assays to explore the mechanics of force-sensing proteins rely on simple perturbations, such as constant or ramped forces. Here, we use our magnetic tweezers design to subject single talin domains to oscillatory forces and external mechanical noise. We show that talin ignores random external fluctuations but synchronizes its folding dynamics with force oscillations in a frequency-dependent way. We hypothesize that this finely tuned response could underpin talin force-sensing properties.
Illuminating the physics of dynamic friction through laboratory earthquakes on thrust faults
Authors: Tal Yuval , Rubino Vito , Rosakis Ares J. , Lapusta Nadia
Published: August 2020

Significance

Our study explores a major challenge in earthquake science—the dynamics of thrust earthquake ruptures as they interact with the Earth’s surface, which is relevant to some of the most destructive earthquakes that have ever occurred. The work illustrates key features of the complex dynamic behavior associated with this interaction using an ultrahigh-speed imaging technique. The interaction leads to large and rapid reductions in normal stress. However, the frictional shear resistance does not decrease instantaneously with normal stress, as typically assumed, but experiences a significant delay. Such delay is important for a range of earthquake source problems that involve rapid normal stress variations.
A cryptic tubulin-binding domain links MEKK1 to curved tubulin protomers
Authors: Filipčík Pavel , Latham Sharissa L. , Cadell Antonia L. , Day Catherine L. , Croucher David R. , Mace Peter D.
Published: August 2020

Significance

The protein kinase MEKK1 activates stress-signaling pathways in response to various cellular stressors, including chemotherapies that disrupt dynamics of the tubulin cytoskeleton. We show that MEKK1 contains a previously uncharacterized domain that can preferentially bind to the curved tubulin heterodimer—which is found in soluble tubulin and at sites of microtubule assembly and disassembly. Mutations that interfere with MEKK1−tubulin binding disrupt microtubule networks in migrating cells and are enriched in patient-derived tumor sequences. These results suggest that MEKK1−tubulin binding may be relevant to cancer progression, and the efficacy of microtubule-disrupting chemotherapies that require the activity of MEKK1.
Naming guides how 12-month-old infants encode and remember objects
Authors: LaTourrette Alexander S. , Waxman Sandra R.
Published: August 2020

Significance

Encoding objects in memory and recalling them later is fundamental to human cognition and emerges in infancy. Here, using a new recognition memory paradigm, we show that the way an object is named, either as a unique individual or as a member of a category, is instrumental in 12-mo-old infants’ encoding of and memory for that object. When the same name is applied consistently to a set of objects, infants encode primarily their commonalities. In contrast, when a unique name is applied to each object, infants encode each object’s unique features. Thus, even as infants begin to produce their first words, a single naming event exerts powerful, nuanced effects on the fundamental cognitive processes of object representation and memory.
Device-quality, reconfigurable metamaterials from shape-directed nanocrystal assembly
Authors: Zhou Wenjie , Liu Zizhuo , Huang Ziyin , Lin Haixin , Samanta Devleena , Lin Qing-Yuan , Aydin Koray , Mirkin Chad A.
Published: August 2020

Significance

Colloidal nanocrystals with defined sizes and shapes are ideal building blocks for nanofabrication. However, the ability to arbitrarily arrange them on surfaces with control over their orientation remains elusive. Here we report a shallow-template-assisted DNA-mediated assembly strategy to precisely arrange colloidal nanocrystals on surfaces, with single-particle control across submillimeter areas. In addition, the oligonucleotide bonds between the nanocrystals and substrate can be reversibly expanded and contracted enabling postsynthetic tunability of the assembled structures. Using this approach, we synthesized a nanocrystal-based, dynamically tunable metasurface (an anomalous reflector), thereby illustrating the potential for unique device construction via DNA programmable assembly.
Quantifying the information impact of future searches for exoplanetary biosignatures
Authors: Balbi Amedeo , Grimaldi Claudio
Published: August 2020

Significance

The search for life on extrasolar worlds by way of spectroscopic biosignature detection is among the most compelling scientific endeavors of the next decades. This article explores the implications of either discovering or ruling out the presence of detectable biosignatures on planets within a few tens of light years from Earth, a distance within reach of future searches. Using a Bayesian methodology, we show that not detecting biosignatures in such sample volume would bring no added information about the galactic population of life-hosting exoplanets. Conversely, if life arose independently on other planets, even a single detection would imply exobiospheres to be more abundant than pulsars. Putative interstellar transfer of life through the panspermia mechanism may, however, significantly lower this estimate.