bluuebunny/crossref_metadata_2025 huggingface dataset:
Modern mass spectrometry in atmospheric sciences: Measurement of volatile organic compounds in the troposphere using proton‐transfer‐reaction mass spectrometry
Authors: Sekimoto Kanako , Koss Abigail R.
Published: July 2020

Volatile organic compounds (VOCs) in the troposphere are emitted from a wide variety of natural and man‐made sources and resulting in environmental issues such as air pollution and climate change. Proton‐transfer‐reaction mass spectrometry (PTR‐MS), a chemical ionization mass spectrometry technique using H3O+ reagent ions, allows real‐time measurements of various VOCs in air with high sensitivity (parts‐per‐trillion to parts‐per‐billion level) and fast time response (<1 s). Modern PTR‐MS equipped with time‐of‐flight mass analyzers can measure hundreds of compounds simultaneously. The applications of PTR‐MS have greatly promoted understanding VOC sources and their roles in environmental issues, and therefore, PTR‐MS has become a well‐established analytical technique for in situ VOC measurements in atmospheric sciences. Here, the principles and implementation of PTR‐MS are described. We additionally highlight modern PTR‐MS techniques for accurate identification and comprehensive quantification of various VOCs. Finally, recent applications for atmospheric science are presented, using examples from research in biomass burning emissions and chemistry.
Fast geometric distortion correction using a deep neural network: Implementation for the 1 Tesla MRI‐Linac system
Authors: Li Mao , Shan Shanshan , Chandra Shekhar S. , Liu Feng , Crozier Stuart
Published: July 2020

Purpose

Combining high‐resolution magnetic resonance imaging (MRI) with a linear accelerator (Linac) as a single MRI‐Linac system provides the capability to monitor intra‐fractional motion and anatomical changes during radiotherapy, which facilitates more accurate delivery of radiation dose to the tumor and less exposure to healthy tissue. The gradient nonlinearity (GNL)‐induced distortions in MRI, however, hinder the implementation of MRI‐Linac system in image‐guided radiotherapy where highly accurate geometry and anatomy of the target tumor is indispensable.

Methods

To correct the geometric distortions in MR images, in particular, for the 1 Tesla (T) MRI‐Linac system, a deep fully connected neural network was proposed to automatically learn the intricate relationship between the undistorted (theoretical) and distorted (real) space. A dataset, consisting of spatial samples acquired by phantom measurement that covers both inside and outside the working diameter of spherical volume (DSV), was utilized for training the neural network, which offers the ability to describe subtle deviations of the GNL field within the entire region of interest (ROI).

Results

The performance of the proposed method was evaluated on MR images of a three‐dimensional (3D) phantom and the pelvic region of an adult volunteer scanned in the 1T MRI‐Linac system. The experimental results showed that the severe geometric distortions within the entire ROI had been successfully corrected with an error less than the pixel size. Also, the presented network is highly efficient, which achieved significant improvement in terms of computational efficiency compared to existing methods.

Conclusions

The feasibility of the presented deep neural network for characterizing the GNL field deviations in the 1T MRI‐Linac system was demonstrated in this study, which shows promise in facilitating the MRI‐Linac system to be routinely implemented in real‐time MRI‐guided radiotherapy.
Copolymer Structure and Performance Consequences of High‐Impact Ethylene–Propylene Copolymers Based on a Ziegler–Natta Catalyst with Novel Internal Donor
Authors: Pellecchia Roberta , Shutov Pavel , Wang Jingbo , Gahleitner Markus
Published: July 2020

Catalyst development for advanced isotactic polypropylene copolymer grades cannot be considered without parallel work on the polymerization process, especially when multi‐phase high‐impact ethylene‐propylene copolymers (also called heterophasic copolymers, HECOs) of complex composition are considered. Using a Ziegler–Natta type catalyst produced in an emulsion process and using citraconate ester as internal donor, a series of such high‐impact copolymers is first produced in a bench‐scale reactor. At this stage, the content of ethylene‐propylene copolymer (EPC) phase is varied in a wide range for understanding the catalyst performance as well as the resulting structure‐property relations, using three‐stage polymerization to emulate multiple reactors. Selected compositions are subsequently scaled up to a multi‐reactor pilot plant, demonstrating composition effects on mechanical performance. Both stages are accompanied by structural investigations using 13C‐NMR spectroscopy and atomic force microscopy. The novel catalyst is found to be capable of synthesizing HECOs in a wide range of elastomer (EPC) content, achieving free‐flowing polymer powders up to an elastomer content as expressed by the xylene cold soluble fraction of 37 wt%.
Enhancement of surface insulation properties of alumina/epoxy composites through ZrO2 film sprayed by plasma atomization
Authors: Lian Hongliang , Yan Jiyuan , Xie Jun , Song Yanze , Zhou Huahao , Kang Yuchan , Lü Fangcheng , Xie Qing
Published: July 2020

Alumina/epoxy composites are widely used in the manufacture of basin insulators, but their surfaces tend to accumulate charges under the high‐voltage direct current (HVDC), which induce the decline of surface insulating property. In this article, the modification method of depositing ZrO2 film sprayed by plasma atomization was proposed to improve the surface insulation performance of the material. Argon was used as the plasma discharge gas, and ZrO (NO3)2.xH2O was used as the zirconium source. The morphology, surface roughness and the element content of materials were measured, and the surface conductivity, flashover voltage, and charge characteristics of the treated samples were tested. The experimental results displayed that a zirconia film was formed on the epoxy resin surface, which restrain the accumulation of surface charges. The surface conductivity of the modified sample was improved by 3 to 4 orders of magnitude, and the flashover voltage was increased by 20%. Studies have shown that: ZrO2 film sprayed by plasma atomization can improve the insulation performance of epoxy resin surface, and it provides an effective method for the surface modification of insulating materials.
Automatic positive airway pressure for obstructive sleep apnea in heart failure with reduced ejection fraction
Authors: Fox Henrik , Bitter Thomas , Sauzet Odile , Rudolph Volker , Oldenburg Olaf
Published: July 2020

Background

Moderate-to-severe obstructive sleep apnea (OSA) is highly prevalent in heart failure patients with reduced left ventricular ejection fraction (HFrEF), and is associated with worsening cardiac function and increased mortality.

Objectives

The automatic positive airway pressure (APAP) trial tested the impact of APAP treatment on changes for the pre-specified endpoints: changes in peak oxygen uptake (peak VO2), percent-predicted peak VO2 and oxygen uptake at anaerobic threshold (VO2-AT).

Methods

This randomized, controlled pilot study included patients with chronic, stable HFrEF who had moderate-to-severe OSA. Patients were randomized 1:1 to either APAP (AutoSet™, ResMed) or nasal strips (control) for 6 months.

Results

76 patients have been randomized and 58 had complete data for final analysis. There was a statistically significant change in the APAP intervention arm for the primary endpoint percent-predicted peak VO2 in comparison to control (67 ± 17 to 73 ± 19%; p = 0.01). Additional primary endpoints peak VO2 and VO2-AT showed a trend in increase in the APAP group. Moreover, there were significant improvements within the APAP group for hypoxemia, left ventricular function and quality of life from baseline to 6 months, but not within the control group (p = 0.001 and p = 0.037, respectively).

Conclusion

APAP intervention was shown to significantly improve outcome compared to control group, represented in percent-predicted peak VO2, an established surrogate marker for cardiovascular prognosis in HFrEF. APAP has additional beneficial effects on hypoxemia, cardiac function and quality of life.
Reading the archive against the grain: Power relations, affective affinities and subjectivity in the documenta Archive
Authors: Dávila-Freire Mela
Published: July 2020

In this article, the documenta Archive is read ‘against the grain’, that is, not in search for art-historically relevant information, but, instead, so as to find traces of subjective biases in its structure and/or emotional contents in its records. The aim of this exercise is to examine the subjective nuances in the archival structure, which every archive preserves even if these are not intentionally recorded. These nuances provide glimpses into an intellectual construction that is otherwise hidden.
Not just a collection of old books: Making the most of donations at the Paul Mellon Centre Library
Authors: Floyd Emma
Published: July 2020

This article shows how large donations of books have transformed the library of the Paul Mellon Centre for Studies in British Art in recent years. Not only have they augmented the collection but they have enhanced the Centre's wider outreach effort and its ability to engage with new audiences.
Hegel’s Dialectical Method: A Response to the Modification View
Authors: Werner Andrew
Published: July 2020

A prevailing view in the literature on Hegel’s dialectical method is that employing it involves advancing a false account and then modifying it to be closer to the truth. I will call this the Modification View. In this essay, I argue that the Modification View is incorrect. Hegel’s insight, I show, is that one can only explain the objective validity of a form of thought through employing that very form. Consequently, the dialectical method cannot relate to its subject matter as something given to it, and so cannot involve advancing and then correcting errors in one’s account.
Comparative studies on two phases of Archaean TTG magmas from different blocks of the North China Craton: petrogenesis and constraints on crustal evolution
Authors: Shan Houxiang , Zhai Mingguo , Mitchell RN , Liu Fu , Guo Jinghui
Published: July 2020

Whole-rock major and trace elements and Hf isotopes of magmatic zircons of tonalite–trondhjemite–granodiorite (TTG) rocks with different ages (2.9, 2.7 and 2.5 Ga) from the three blocks (the Eastern Block, Western Block and Trans-North China Orogen) of the North China Craton were compiled to investigate their respective petrogenesis, tectonic setting and implications for crustal growth and evolution. Geochemical features of the 2.5 Ga TTGs of the Eastern Block require melting of predominant rutile-bearing eclogite and subordinate garnet-amphibolite at higher pressure, while the source material of the 2.7 Ga TTGs is garnet-amphibolite or granulite at lower pressure. The 2.5 Ga TTGs have high Mg#, Cr and Ni, negative Nb–Ta anomalies and a juvenile basaltic crustal source, indicating derivation from the melting of a subducting slab. In contrast, features of the 2.7 Ga TTGs suggest generation from melting of thickened lower crust. The 2.5 and 2.7 Ga TTGs in the Trans-North China Orogen were formed at garnet-amphibolite to eclogite facies, and the source material of the 2.5 Ga TTGs in the Western Block is most likely garnet-amphibolite or eclogite. The 2.5 Ga TTGs in the Trans-North China Orogen and Western Block were generated by the melting of a subducting slab, whereas the 2.7 Ga TTGs in the Trans-North China Orogen derived from melting of thickened lower crust. The Hf isotopic data suggest both the 2.5 and 2.7 Ga TTG magmas were involved with contemporary crustal growth and reworking. The two-stage model age (TDM2) histograms show major crustal growth between 2.9 and 2.7 Ga for the whole North China Craton.
New Lights on Raja Krishnachandra and Early Hindu-European Intellectual Exchange
Authors: EHRLICH JOSHUA
Published: July 2020

This article presents and analyses two previously unknown sources on Raja Krishnachandra of Nadia (1710–83). While the raja has long been famed in Bengal as a patron of brahmans, scholarship on him has had to contend with a lack of evidence. The two new sources, reports of conversations between Krishnachandra and Europeans, furnish insights into his mind and milieu. They support recent arguments that he used brahmanical patronage to buttress his authority, and deception to deal with the ascendant East India Company. Their greatest contribution, however, is to reveal that the raja sought an active engagement with foreign intellectual traditions. They suggest that eighteenth-century Hindu learning, far from being inherently hidebound or insular, was amenable to outside influences.
Methodische Anmerkungen und Anwendungsbereiche der Furchtkonditionierung in verschiedenen psychologischen Disziplinen
Authors: Merz Christian J. , Lonsdorf Tina B.
Published: July 2020

Zusammenfassung. Die Furchtkonditionierung stellt ein bedeutsames Paradigma zur Untersuchung von emotionalen Lern- und Gedächtnisprozessen dar. Nach einer ungefähr hundertjährigen Geschichte wird deutlich, dass die Furchtkonditionierung nicht nur einen wichtigen Beitrag zur speziesübergreifenden Grundlagenforschung liefert, sondern auch unterschiedliche Anwendungsfelder zu neuen Erkenntnissen inspirieren kann. In diesem Übersichtartikel soll das grundlegende Paradigma mit verschiedenen methodischen Überlegungen zur experimentellen Durchführung vorgestellt werden. Im Anschluss werden ausgewählte Anwendungsbereiche der Furchtkonditionierung innerhalb der psychologischen Disziplinen dargestellt: die Allgemeine Psychologie wird bezüglich allgemeingültiger Gesetzmäßigkeiten von Lern- und Gedächtnisprozessen angesprochen, die Differentielle Psychologie wegen bedeutsamer interindividueller Unterschiede, die Biologische Psychologie und Neuropsychologie in Bezug auf physiologische und anatomische Grundlagen der Furchtkonditionierung, die Sozialpsychologie im Zuge der Einstellungsforschung, die Entwicklungspsychologie aufgrund altersspezifischer Aspekte sowie die Klinische Psychologie und Psychotherapie im Hinblick auf die Pathogenese von Angsterkrankungen und der Expositionstherapie. Insgesamt betrachtet hat die Furchtkonditionierung das Potenzial nicht nur unterschiedliche Disziplinen der Psychologie in synergistischer Weise zusammenzubringen, sondern auch die verschiedenen inhaltlichen Schwerpunkte zu unterstreichen.
Current trends in gene recovery mediated by the CRISPR-Cas system
Authors: Jang Hyeon-Ki , Song Beomjong , Hwang Gue-Ho , Bae Sangsu
Published: July 2020

The CRISPR-Cas system has undoubtedly revolutionized the genome editing field, enabling targeted gene disruption, regulation, and recovery in a guide RNA-specific manner. In this review, we focus on currently available gene recovery strategies that use CRISPR nucleases, particularly for the treatment of genetic disorders. Through the action of DNA repair mechanisms, CRISPR-mediated DNA cleavage at a genomic target can shift the reading frame to correct abnormal frameshifts, whereas DNA cleavage at two sites, which can induce large deletions or inversions, can correct structural abnormalities in DNA. Homology-mediated or homology-independent gene recovery strategies that require donor DNAs have been developed and widely applied to precisely correct mutated sequences in genes of interest. In contrast to the DNA cleavage-mediated gene correction methods listed above, base-editing tools enable base conversion in the absence of donor DNAs. In addition, CRISPR-associated transposases have been harnessed to generate a targeted knockin, and prime editors have been developed to edit tens of nucleotides in cells. Here, we introduce currently developed gene recovery strategies and discuss the pros and cons of each.
Structural basis of seamless excision and specific targeting by piggyBac transposase
Authors: Chen Qiujia , Luo Wentian , Veach Ruth Ann , Hickman Alison B. , Wilson Matthew H. , Dyda Fred
Published: July 2020

The piggyBac DNA transposon is used widely in genome engineering applications. Unlike other transposons, its excision site can be precisely repaired without leaving footprints and it integrates specifically at TTAA tetranucleotides. We present cryo-EM structures of piggyBac transpososomes: a synaptic complex with hairpin DNA intermediates and a strand transfer complex capturing the integration step. The results show that the excised TTAA hairpin intermediate and the TTAA target adopt essentially identical conformations, providing a mechanistic link connecting the two unique properties of piggyBac. The transposase forms an asymmetric dimer in which the two central domains synapse the ends while two C-terminal domains form a separate dimer that contacts only one transposon end. In the strand transfer structure, target DNA is severely bent and the TTAA target is unpaired. In-cell data suggest that asymmetry promotes synaptic complex formation, and modifying ends with additional transposase binding sites stimulates activity.
Mechano-modulatory synthetic niches for liver organoid derivation
Authors: Sorrentino Giovanni , Rezakhani Saba , Yildiz Ece , Nuciforo Sandro , Heim Markus H. , Lutolf Matthias P. , Schoonjans Kristina
Published: July 2020

The recent demonstration that primary cells from the liver can be expanded in vitro as organoids holds enormous promise for regenerative medicine and disease modelling. The use of three-dimensional (3D) cultures based on ill-defined and potentially immunogenic matrices, however, hampers the translation of liver organoid technology into real-life applications. We here use chemically defined hydrogels for the efficient derivation of both mouse and human hepatic organoids. Organoid growth is found to be highly stiffness-sensitive, a mechanism independent of acto-myosin contractility and requiring instead activation of the Src family of kinases (SFKs) and yes-associated protein 1 (YAP). Aberrant matrix stiffness, on the other hand, results in compromised proliferative capacity. Finally, we demonstrate the establishment of biopsy-derived human liver organoids without the use of animal components at any step of the process. Our approach thus opens up exciting perspectives for the establishment of protocols for liver organoid-based regenerative medicine.
Giant room temperature anomalous Hall effect and tunable topology in a ferromagnetic topological semimetal Co2MnAl
Authors: Li Peigang , Koo Jahyun , Ning Wei , Li Jinguo , Miao Leixin , Min Lujin , Zhu Yanglin , Wang Yu , Alem Nasim , Liu Chao-Xing , Mao Zhiqiang , Yan Binghai
Published: July 2020

Weyl semimetals exhibit unusual surface states and anomalous transport phenomena. It is hard to manipulate the band structure topology of specific Weyl materials. Topological transport phenomena usually appear at very low temperatures, which sets challenges for applications. In this work, we demonstrate the band topology modification via a weak magnetic field in a ferromagnetic Weyl semimetal candidate, Co2MnAl, at room temperature. We observe a tunable, giant anomalous Hall effect (AHE) induced by the transition involving Weyl points and nodal rings. The AHE conductivity is as large as that of a 3D quantum AHE, with the Hall angle (ΘH) reaching a record value ($$\tan {\Theta }^{H}=0.21$$
tan

Θ

H

=
0.21
) at the room temperature among magnetic conductors. Furthermore, we propose a material recipe to generate large AHE by gaping nodal rings without requiring Weyl points. Our work reveals an intrinsically magnetic platform to explore the interplay between magnetic dynamics and topological physics for developing spintronic devices.
A single-hole spin qubit
Authors: Hendrickx N. W. , Lawrie W. I. L. , Petit L. , Sammak A. , Scappucci G. , Veldhorst M.
Published: July 2020

Qubits based on quantum dots have excellent prospects for scalable quantum technology due to their compatibility with standard semiconductor manufacturing. While early research focused on the simpler electron system, recent demonstrations using multi-hole quantum dots illustrated the favourable properties holes can offer for fast and scalable quantum control. Here, we establish a single-hole spin qubit in germanium and demonstrate the integration of single-shot readout and quantum control. We deplete a planar germanium double quantum dot to the last hole, confirmed by radio-frequency reflectrometry charge sensing. To demonstrate the integration of single-shot readout and qubit operation, we show Rabi driving on both qubits. We find remarkable electric control over the qubit resonance frequencies, providing great qubit addressability. Finally, we analyse the spin relaxation time, which we find to exceed one millisecond, setting the benchmark for hole quantum dot qubits. The ability to coherently manipulate a single hole spin underpins the quality of strained germanium and defines an excellent starting point for the construction of quantum hardware.
Modular microfluidics enables kinetic insight from time-resolved cryo-EM
Authors: Mäeots Märt-Erik , Lee Byungjin , Nans Andrea , Jeong Seung-Geun , Esfahani Mohammad M. N. , Ding Shan , Smith Daniel J. , Lee Chang-Soo , Lee Sung Sik , Peter Matthias , Enchev Radoslav I.
Published: July 2020

Mechanistic understanding of biochemical reactions requires structural and kinetic characterization of the underlying chemical processes. However, no single experimental technique can provide this information in a broadly applicable manner and thus structural studies of static macromolecules are often complemented by biophysical analysis. Moreover, the common strategy of utilizing mutants or crosslinking probes to stabilize intermediates is prone to trapping off-pathway artefacts and precludes determining the order of molecular events. Here we report a time-resolved sample preparation method for cryo-electron microscopy (trEM) using a modular microfluidic device, featuring a 3D-mixing unit and variable delay lines that enables automated, fast, and blot-free sample vitrification. This approach not only preserves high-resolution structural detail but also substantially improves sample integrity and protein distribution across the vitreous ice. We validate the method by visualising reaction intermediates of early RecA filament growth across three orders of magnitude on sub-second timescales. The trEM method reported here is versatile, reproducible, and readily adaptable to a broad spectrum of fundamental questions in biology.
Spatial defects nanoengineering for bipolar conductivity in MoS2
Authors: Zheng Xiaorui , Calò Annalisa , Cao Tengfei , Liu Xiangyu , Huang Zhujun , Das Paul Masih , Drndic Marija , Albisetti Edoardo , Lavini Francesco , Li Tai-De , Narang Vishal , King William P. , Harrold John W. , Vittadello Michele , Aruta Carmela , Shahrjerdi Davood , Riedo Elisa
Published: July 2020

Understanding the atomistic origin of defects in two-dimensional transition metal dichalcogenides, their impact on the electronic properties, and how to control them is critical for future electronics and optoelectronics. Here, we demonstrate the integration of thermochemical scanning probe lithography (tc-SPL) with a flow-through reactive gas cell to achieve nanoscale control of defects in monolayer MoS2. The tc-SPL produced defects can present either p- or n-type doping on demand, depending on the used gasses, allowing the realization of field effect transistors, and p-n junctions with precise sub-μm spatial control, and a rectification ratio of over 104. Doping and defects formation are elucidated by means of X-Ray photoelectron spectroscopy, scanning transmission electron microscopy, and density functional theory. We find that p-type doping in HCl/H2O atmosphere is related to the rearrangement of sulfur atoms, and the formation of protruding covalent S-S bonds on the surface. Alternatively, local heating MoS2 in N2 produces n-character.
3D printing of multi-scalable structures via high penetration near-infrared photopolymerization
Authors: Zhu Junzhe , Zhang Qiang , Yang Tianqing , Liu Yu , Liu Ren
Published: July 2020

3D printing consisted of in-situ UV-curing module can build complex 3D structures, in which direct ink writing can handle versatile materials. However, UV-based direct ink writing (DIW) is facing a trade-off between required curing intensity and effectiveness range, and it cannot implement multiscale parallelization at ease. We overcome these difficulties by ink design and introducing near-infrared (NIR) laser assisted module, and this increases the scalability of direct ink writing to solidify the deposited filament with diameter up to 4 mm, which is much beyond any of existing UV-assisted DIW. The NIR effectiveness range can expand to tens of centimeters and deliver the embedded writing capability. We also demonstrate its parallel manufacturing capability for simultaneous curing of multi-color filaments and freestanding objects. The strategy owns further advantages to be integrated with other types of ink-based 3D printing technologies for extensive applications.
A cytoskeleton regulator AVIL drives tumorigenesis in glioblastoma
Authors: Xie Zhongqiu , Janczyk Pawel Ł. , Zhang Ying , Liu Aiqun , Shi Xinrui , Singh Sandeep , Facemire Loryn , Kubow Kristopher , Li Zi , Jia Yuemeng , Schafer Dorothy , Mandell James W. , Abounader Roger , Li Hui
Published: July 2020

Glioblastoma is a deadly cancer, with no effective therapies. Better understanding and identification of selective targets are urgently needed. We found that advillin (AVIL) is overexpressed in all the glioblastomas we tested including glioblastoma stem/initiating cells, but hardly detectable in non-neoplastic astrocytes, neural stem cells or normal brain. Glioma patients with increased AVIL expression have a worse prognosis. Silencing AVIL nearly eradicated glioblastoma cells in culture, and dramatically inhibited in vivo xenografts in mice, but had no effect on normal control cells. Conversely, overexpressing AVIL promoted cell proliferation and migration, enabled fibroblasts to escape contact inhibition, and transformed immortalized astrocytes, supporting AVIL being a bona fide oncogene. We provide evidence that the tumorigenic effect of AVIL is partly mediated by FOXM1, which regulates LIN28B, whose expression also correlates with clinical prognosis. AVIL regulates the cytoskeleton through modulating F-actin, while mutants disrupting F-actin binding are defective in its tumorigenic capabilities.
Biological rhythms in the deep-sea hydrothermal mussel Bathymodiolus azoricus
Authors: Mat Audrey M. , Sarrazin Jozée , Markov Gabriel V. , Apremont Vincent , Dubreuil Christine , Eché Camille , Fabioux Caroline , Klopp Christophe , Sarradin Pierre-Marie , Tanguy Arnaud , Huvet Arnaud , Matabos Marjolaine
Published: July 2020

Biological rhythms are a fundamental property of life. The deep ocean covers 66% of our planet surface and is one of the largest biomes. The deep sea has long been considered as an arrhythmic environment because sunlight is totally absent below 1,000 m depth. In the present study, we have sequenced the temporal transcriptomes of a deep-sea species, the ecosystem-structuring vent mussel Bathymodiolus azoricus. We reveal that tidal cycles predominate in the transcriptome and physiology of mussels fixed directly at hydrothermal vents at 1,688 m depth at the Mid-Atlantic Ridge, whereas daily cycles prevail in mussels sampled after laboratory acclimation. We identify B. azoricus canonical circadian clock genes, and show that oscillations observed in deep-sea mussels could be either a direct response to environmental stimulus, or be driven endogenously by one or more biological clocks. This work generates in situ insights into temporal organisation in a deep-sea organism.
Mnemonic prediction errors bias hippocampal states
Authors: Bein Oded , Duncan Katherine , Davachi Lila
Published: July 2020

When our experience violates our predictions, it is adaptive to upregulate encoding of novel information, while down-weighting retrieval of erroneous memory predictions to promote an updated representation of the world. We asked whether mnemonic prediction errors promote hippocampal encoding versus retrieval states, as marked by distinct network connectivity between hippocampal subfields. During fMRI scanning, participants were cued to internally retrieve well-learned complex room-images and were then presented with either an identical or a modified image (0-4 changes). In the left hemisphere, we find that CA1-entorhinal connectivity increases, and CA1-CA3 connectivity decreases, with the number of changes. Further, in the left CA1, the similarity between activity patterns during cued-retrieval of the learned room and during the image is lower when the image includes changes, consistent with a prediction error signal in CA1. Our findings provide a mechanism by which mnemonic prediction errors may drive memory updating—by biasing hippocampal states.
Liquid metal-based synthesis of high performance monolayer SnS piezoelectric nanogenerators
Authors: Khan Hareem , Mahmood Nasir , Zavabeti Ali , Elbourne Aaron , Rahman Md. Ataur , Zhang Bao Yue , Krishnamurthi Vaishnavi , Atkin Paul , Ghasemian Mohammad B. , Yang Jiong , Zheng Guolin , Ravindran Anil R. , Walia Sumeet , Wang Lan , Russo Salvy P. , Daeneke Torben , Li Yongxiang , Kalantar-Zadeh Kourosh
Published: July 2020

The predicted strong piezoelectricity for monolayers of group IV monochalcogenides, together with their inherent flexibility, makes them likely candidates for developing flexible nanogenerators. Within this group, SnS is a potential choice for such nanogenerators due to its favourable semiconducting properties. To date, access to large-area and highly crystalline monolayer SnS has been challenging due to the presence of strong inter-layer interactions by the lone-pair electrons of S. Here we report single crystal across-the-plane and large-area monolayer SnS synthesis using a liquid metal-based technique. The characterisations confirm the formation of atomically thin SnS with a remarkable carrier mobility of ~35 cm2 V−1 s−1 and piezoelectric coefficient of ~26 pm V−1. Piezoelectric nanogenerators fabricated using the SnS monolayers demonstrate a peak output voltage of ~150 mV at 0.7% strain. The stable and flexible monolayer SnS can be implemented into a variety of systems for efficient energy harvesting.
A diradical based on odd-electron σ-bonds
Authors: Yang Wenbang , Zhang Li , Xiao Dengmengfei , Feng Rui , Wang Wenqing , Pan Sudip , Zhao Yue , Zhao Lili , Frenking Gernot , Wang Xinping
Published: July 2020

The concept of odd-electron σ–bond was first proposed by Linus Pauling. Species containing such a bond have been recognized as important intermediates encountered in many fields. A number of radicals with a one-electron or three-electron σ-bond have been isolated, however, no example of a diradical based odd-electron σ-bonds has been reported. So far all stable diradicals are based on twos/p-localized orπ-delocalized unpaired electrons (radicals). Here, we report a dication diradical that is based on two Se∴Se three-electron σ–bonds. In contrast, the dication of sulfur analogue does not display diradical character but exhibits a closed-shell singlet.
Cryo-EM structure of catalytic ribonucleoprotein complex RNase MRP
Authors: Perederina Anna , Li Di , Lee Hyunwook , Bator Carol , Berezin Igor , Hafenstein Susan L. , Krasilnikov Andrey S.
Published: July 2020

RNase MRP is an essential eukaryotic ribonucleoprotein complex involved in the maturation of rRNA and the regulation of the cell cycle. RNase MRP is related to the ribozyme-based RNase P, but it has evolved to have distinct cellular roles. We report a cryo-EM structure of the S. cerevisiae RNase MRP holoenzyme solved to 3.0 Å. We describe the structure of this 450 kDa complex, interactions between its components, and the organization of its catalytic RNA. We show that some of the RNase MRP proteins shared with RNase P undergo an unexpected RNA-driven remodeling that allows them to bind to divergent RNAs. Further, we reveal how this RNA-driven protein remodeling, acting together with the introduction of new auxiliary elements, results in the functional diversification of RNase MRP and its progenitor, RNase P, and demonstrate structural underpinnings of the acquisition of new functions by catalytic RNPs.
Exchange-correlation functionals for band gaps of solids: benchmark, reparametrization and machine learning
Authors: Borlido Pedro , Schmidt Jonathan , Huran Ahmad W. , Tran Fabien , Marques Miguel A. L. , Botti Silvana
Published: July 2020

We conducted a large-scale density-functional theory study on the influence of the exchange-correlation functional in the calculation of electronic band gaps of solids. First, we use the large materials data set that we have recently proposed to benchmark 21 different functionals, with a particular focus on approximations of the meta-generalized-gradient family. Combining these data with the results for 12 functionals in our previous work, we can analyze in detail the characteristics of each approximation and identify its strong and/or weak points. Beside confirming that mBJ, HLE16 and HSE06 are the most accurate functionals for band gap calculations, we reveal several other interesting functionals, chief among which are the local Slater potential approximation, the GGA AK13LDA, and the meta-GGAs HLE17 and TASK. We also compare the computational efficiency of these different approximations. Relying on these data, we investigate the potential for improvement of a promising subset of functionals by varying their internal parameters. The identified optimal parameters yield a family of functionals fitted for the calculation of band gaps. Finally, we demonstrate how to train machine learning models for accurate band gap prediction, using as input structural and composition data, as well as approximate band gaps obtained from density-functional theory.
Group structure and kinship in beluga whale societies
Authors: O’Corry-Crowe Greg , Suydam Robert , Quakenbush Lori , Smith Thomas G. , Lydersen Christian , Kovacs Kit M. , Orr Jack , Harwood Lois , Litovka Dennis , Ferrer Tatiana
Published: July 2020

Evolutionary explanations for mammalian sociality typically center on inclusive-fitness benefits of associating and cooperating with close kin, or close maternal kin as in some whale societies, including killer and sperm whales. Their matrilineal structure has strongly influenced the thinking about social structure in less well-studied cetaceans, including beluga whales. In a cross-sectional study of group structure and kinship we found that belugas formed a limited number of distinct group types, consistently observed across populations and habitats. Certain behaviours were associated with group type, but group membership was often dynamic. MtDNA-microsatellite profiling combined with relatedness and network analysis revealed, contrary to predictions, that most social groupings were not predominantly organized around close maternal relatives. They comprised both kin and non-kin, many group members were paternal rather than maternal relatives, and unrelated adult males often traveled together. The evolutionary mechanisms that shape beluga societies are likely complex; fitness benefits may be achieved through reciprocity, mutualism and kin selection. At the largest scales these societies are communities comprising all ages and both sexes where multiple social learning pathways involving kin and non-kin can foster the emergence of cultures. We explore the implications of these findings for species management and the evolution of menopause.
Associations of nicotidamide-N-methyltransferase, FTO, and IRX3 genetic variants with body mass index and resting energy expenditure in Mexican subjects
Authors: Bañales-Luna Maciel , Figueroa-Vega Nicté , Marín-Aragón Carolina Ivet , Perez-Luque Elva , Ibarra-Reynoso Lorena , Gallardo-Blanco Hugo L. , López-Aguilar Itzel , Malacara Juan Manuel
Published: July 2020

The enzyme nicotidamide-N-methyltransferase (NNMT) regulates adipose tissue energy expenditure through increasing nicotinamide adenosine dinucleotide (NAD+) content. NNMT methylates nicotinamide to N1-methylnicotidamide (MNA-1) using S-adenosyl methionine. The rs694539 NNMT polymorphism is associated with non-alcoholic steatohepatitis, and rs1941404 is associated with hyperlipidemia. The rs1421085 FTO is related to poor eating behaviors, and rs3751723 IRX3 is associated with obesity. To investigate the association of rs694539 and rs1941404 NNMT, rs140285 FTO and rs3751723 IRX3 polymorphisms with MNA-1 concentrations, resting energy expenditure (REE) and BMI, we included clinically healthy Mexican subjects 30 to 50 years old, 100 subjects (35 men/65 women) with BMI > 30 kg/m2 and 100 subjects (32 men/68 women) with BMI < 25 kg/m2. Glucose, lipid profile, insulin, leptin, acylated ghrelin, and MNA-1 (LC–MS) were quantified. Resting energy expenditure (REE) was estimated using indirect calorimetry with a Fitmate instrument. Genotyping was performed using PCR–RFLP, and allelic discrimination was examined using TaqMan probes. MNA-1 concentrations and REE were significantly higher in obese subjects. Subjects with the rs694539AA NNMT genotype (recessive model) had lower weight, BMI, and REE. BMI showed an association with HDL-C, triglycerides, MNA-1, acetylated ghrelin, leptin, insulin concentrations, HOMA-IR, REE, and rs1421085. Subjects with the TC or CC genotypes of rs1421085 FTO showed 6 kg and 2 units of BMI more than did those with the TT wild type. The CG of the rs1421085 and rs3751723 haplotypes was associated with BMI. These findings showed that BMI was strongly associated with REE, rs1421085 FTO and the CG rs1421085 FTO and rs3751723 IRX3 haplotypes. We used the GMDR approach in obesity phenotype to show the interaction of four SNPs and metabolic variables.
Non-reassuring foetal status and sleep problems in 1-year-old infants in the Japan Environment and Children’s Study: a cohort study
Authors: Nakahara Kazushige , Michikawa Takehiro , Morokuma Seiichi , Ogawa Masanobu , Kato Kiyoko , Sanefuji Masafumi , Shibata Eiji , Tsuji Mayumi , Shimono Masayuki , Kawamoto Toshihiro , Ohga Shouichi , Kusuhara Koichi ,   The Japan Environment and Children’s Study Group, Kamijima Michihiro , Yamazaki Shin , Ohya Yukihiro , Kishi Reiko , Yaegashi Nobuo , Hashimoto Koichi , Mori Chisato , Ito Shuichi , Yamagata Zentaro , Inadera Hidekuni , Nakayama Takeo , Iso Hiroyasu , Shima Masayuki , Kurozawa Youichi , Suganuma Narufumi , Katoh Takahiko
Published: July 2020

Abnormal autonomic function may cause false-positive non-reassuring foetal status (fpNRFS) and may also cause sleeping problems after birth. However, an association between fpNRFS and sleeping problems in infants has not been reported. We previously showed an association of NRFS with temperament, including bad mood and frequent crying for long durations in 1-month-old infants. In the present study, we aimed to assess this association in 1-year-old infants. A total of 62,612 single pregnant women were included in the analysis. fpNRFS was identified from medical records. Sleep problems, such as short sleep duration or crying at night, were investigated in 1-year-old infants using a questionnaire for mothers. We used a log-binominal regression model to explore the association of fpNRFS with each sleep problem and to estimate risk ratios (RRs). The number of fpNRFS cases was 2,071, with a frequency of 3.3%. We observed an association of fpNRFS with shorter sleep duration of less than 8 h a night (RR 1.30, 95% confidence intervals [CI] 1.10–1.54), crying at night (RR 1.19, 95% CI 1.03–1.39), and bedtime after 22:00 (RR 1.09, 95% CI 1.00–1.18). fpNRFS may be associated with sleep problems in 1-year-old infants.
Cortical spreading depolarisation-induced facial hyperalgesia, photophobia and hypomotility are ameliorated by sumatriptan and olcegepant
Authors: Tang Chunhua , Unekawa Miyuki , Kitagawa Satoshi , Takizawa Tsubasa , Kayama Yohei , Nakahara Jin , Shibata Mamoru
Published: July 2020

Cortical spreading depolarisation (CSD), the neural mechanism underlying migraine aura, may cause headache by sensitising the trigeminal system. Photophobia, the most bothersome accompanying symptom during migraine attacks, is more prevalent in migraine with aura than in migraine without aura. Whether CSD plays a role in developing photophobia remains unknown. Moreover, migraine-induced physical hypoactivity contributes to loss of productivity. We aimed to investigate the development of trigeminal sensitisation, photophobia and locomotive abnormality after KCl-induced CSD using 86 male C57BL/6 mice. Sham-operated mice were used as controls. We confirmed the presence of trigeminal sensitisation and photophobia at 24 h after CSD. CSD-subjected mice also exhibited significantly reduced locomotive activity in both light and dark zones. Hence, the CSD-induced hypomobility was likely to be independent of photophobia. The 5-HT1B/1D agonist, sumatriptan, corrected all these CSD-induced abnormalities. Moreover, dose dependency was demonstrated in the ameliorating effect of the calcitonin gene-related peptide (CGRP) receptor antagonist, olcegepant, on these abnormalities. Sumatriptan and olcegepant improved mouse locomotion with therapeutic lags ranging from 20 to 30 min. Collectively, CSD caused trigeminal sensitisation, photophobia and hypomobility that persisted for at least 24 h by a mechanism involving the 5-HT1B/1D and CGRP activity.
Increased large-scale inter-network connectivity in relation to impulsivity in Parkinson’s disease
Authors: Koh Jinsoo , Kaneoke Yoshiki , Donishi Tomohiro , Ishida Takuya , Sakata Mayumi , Hiwatani Yasuhiro , Nakayama Yoshiaki , Yasui Masaaki , Ishiguchi Hiroshi , Hironishi Masaya , Murata Ken-ya , Terada Masaki , Ito Hidefumi
Published: July 2020

Impulsivity is a neuropsychiatric feature of Parkinson’s disease (PD). We investigated the pathophysiology of impulsivity in PD using resting-state functional magnetic resonance imaging (rs-fMRI). We investigated 45 patients with idiopathic PD and 21 healthy controls. Based on Barratt Impulsiveness Scale (BIS-11) score, PD patients were classified as higher (PD-HI) or lower impulsivity (PD-LI). Functional connectivity (FC) between various large-scale brain networks were analysed using the CONN toolbox. FC between the right frontoparietal network (FPN) and medial visual network (MVN) was significantly higher in PD-HI patients than PD-LI patients (false discovery rate [FDR]-adjusted p = 0.0315). FC between the right FPN and MVN had a significant positive correlation with total BIS-11 score (FDR-adjusted p = 0.010) and the attentional impulsivity (FDR-adjusted p = 0.046) and non-planning impulsivity subscale scores (FDR-adjusted p = 0.018). On the other hand, motor impulsivity subscale score had a significant negative correlation with the FC between the default-mode and salience networks (right supramarginal gyrus, FDR-adjusted p = 0.018; anterior cingulate cortex, FDR-adjusted p = 0.027); this trend was observed in healthy controls. The attentional and non-planning impulsivity, regarded as ‘cognitive’ impulsivity, may be associated with dysfunction in integration of perceptual information and flexible cognitive control in PD.
The profiles and tensile strength on straight roots of plants withstand transient tensile injured after self-repair
Authors: Wang Chenglong , Zhang Xin , Liu Jing , Wang Bo , Li Youfang , Li Qiang
Published: July 2020

Plants roots are severely injured during the process of withstanding transient tensile, and the injured roots can self-repair. We investigated the change law of the growth characteristics and tensile strength on straight roots withstand transient tensile injured after self-repair. The survival rate of two kinds of injured plants roots was between 60 and 89%. The test roots after self-repaired, the tensile strength reduction rate of Hippophae rhamnoides L. roots was greater than that of Salix psammophila roots. The tensile force was positively related to the power function of root diameter, the tensile strength was negatively related to the root diameter in a power function. The tensile strength of straight roots under small injured force showed an increasing trend, but the straight roots under the large injured force showed the opposite result. The survival rate of rough roots was greater than that of fine roots. The large injured force was not conducive to the repair and force again of the straight roots of two kinds of plants. The reduction rate of tensile strength after repaired with small force was less than that of large force. The self-repair ability of fine roots was weaker than that of rough roots.
Predicting in-season maize (Zea mays L.) yield potential using crop sensors and climatological data
Authors: Dhillon Jagmandeep , Aula Lawrence , Eickhoff Elizabeth , Raun William
Published: July 2020

The environment randomly influences nitrogen (N) response, demand, and optimum N rates. Field experiments were conducted at Lake Carl Blackwell (LCB) and Efaw Agronomy Research Station (Efaw) from 2015 to 2018 in Oklahoma, USA. Fourteen site years of data were used from two different trials, namely Regional Corn (Regional) and Optimum N rate (Optimum N). Three algorithms developed by Oklahoma State University (OSU) to predict yield potential were tested on both trials. Furthermore, three new models for predicting potential yield using optical crop sensors and climatological data were developed for maize in rain-fed conditions. The models were trained/built using Regional and were then validated/tested on the Optimum N trial. Out of three models, one model was developed using all of the Regional trial (combined model), and the other two were prepared from each location LCB and Efaw model. Of the three current algorithms; one worked best at predicting final grain yield at LCB location only. The coefficient of determination R2 = 0.15 and 0.16 between actual grain yield and predicted grain yield was observed for Regional and Optimum N rate trials, respectively. The results further indicated that the new models were better at predicting final grain yield except for Efaw model (R2 = 0.04) when tested on optimum N trial. Grain yield prediction for the combined model had an R2 = 0.31. The best yield prediction was obtained at LCB with an R2 = 0.52. Including climatological data significantly improved the ability to predict final grain yield along with using mid-season sensor data.
Topologically protected spin diffusion and spin generator using chalcogenide superlattices
Authors: Tominaga Junji , Miyata Noriyuki , Sumi Satoshi , Awano Hiroyuki , Murakami Shuichi
Published: July 2020

Spintronics is expected to be the basis for future ultra-low-energy nanoelectronic devices. To operate such devices at room temperature, amplifiers, batteries, capacitors, as well as spin current sources are required. Here we report a chalcogenide superlattice composed of GeTe and Sb2Te3 layers that have a topologically protected spin diffusion length exceeding 100 μm at room temperature. A spin generator is demonstrated by combining magnetic injectors (TbFeCo) with this superlattice. The spin current was found to increase exponentially with the number of superlattice periods. We used this effect to demonstrate a 15-fold increase in the spin current. In addition, spin rectification is possible by growing the superlattice layers with atomic-level thickness accuracy. The reported chalcogenide superlattice spin generators and rectifiers open new opportunities to design low-energy spintronic integrated circuits and quantum computers.
Dietary bioactive ingredients to modulate the gut microbiota-derived metabolite TMAO. New opportunities for functional food development
Authors: Simó C. , García-Cañas V.
Published: July 2020

Diet could play a dual role in the production of the TMA/TMAOmeta-organismal pathway since it provides TMA precursors, but also other dietary constituents that reduce endogenous TMAO or its damaging effects through different mechanisms.
Correlative cathodoluminescence electron microscopy bioimaging: towards single protein labelling with ultrastructural context
Authors: Keevend Kerda , Coenen Toon , Herrmann Inge K.
Published: July 2020

We discuss the opportunities and challenges of correlative cathodoluminescence electron microscopy for biomedical applications.