bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrogen bonding driven self‐assembly of side‐chain amino acid and fatty acid appended poly(methacrylate)s: Gelation and application in oil spill recovery
Authors: Nandi Mridula , Maiti Binoy , Banerjee Soham , De Priyadarsi
Published: December 2018

We report an interesting class of fatty acid appended side‐chain phenylalanine (Phe) containing poly(methacrylate) homopolymers that undergo self‐assembly leading to gelation in selective organic hydrocarbons, due to association among the side‐chain functionalities. Fatty acids of different n‐alkyl chain lengths have been attached to the N‐terminal of the Phe‐based methacrylate and the corresponding homopolymers have been synthesized via reversible addition–fragmentation chain transfer polymerization. These homopolymers undergo gelation in selective organic hydrocarbons. The morphology of these organogels has been characterized by field emission scanning electron microscopy which revealed macroporous structure of the organogels. Viscoelastic properties of organogels and the thermoreversible gel‐to‐sol transition have been investigated by rheological measurements. Powder X‐ray diffraction study has been performed to understand the effect of long n‐alkyl chains on the gelation process. FTIR study reveals inter‐/intra‐chain hydrogen bonding which is the driving force of organogelation of the polymers in suitable solvents. In absence of hydrogen bonding interaction, hydrophobic association fails to direct the self‐assembly process and no gelation is observed. An interesting feature of the homopolymeric gelators is that it can selectively congeal the diesel part from an oil–water biphasic mixture, which might be useful in oil spill treatment. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 511–521
Tributes Received in Honor of M. Sam Mannan
Authors: Sanders Roy E.
Published: December 2018

Dr. M. Sam Mannan was a great promoter of Chemical Process Safety. He was friendly, playful, respectful, and supportive to everyone he encountered. Upon his death, heartfelt tributes from his students, his friends, and his colleagues both in the United States and internationally came pouring in. There was not sufficient space to accommodate them all; however, below is a selection. Several tributes below were initially posted on the Hillier Funeral Home Tribute Wall. © 2018 American Institute of Chemical Engineers Process Saf Prog 37: 448–451, 2018
Geometric calibration of markerless optical surgical navigation system
Authors: Lin Qinyong , Cai Ken , Yang Rongqian , Xiao Weihu , Huang Jinhua , Zhan Yinwei , Zhuang Jian
Published: December 2018

Background

Patient‐to‐image registration is required for image‐guided surgical navigation, but marker‐based registration is time consuming and is subject to manual error. Markerless registration is an alternative solution to avoid these issues.

Methods

This study designs a calibration board and proposes a geometric calibration method to calibrate the near‐infrared tracking and structured light components of the proposed optical surgical navigation system simultaneously.

Results

A planar board and a cylinder are used to evaluate the accuracy of calibration. The mean error for the board experiment is 0.035 mm, and the diameter error for the cylinder experiment is 0.119 mm. A calibration board is reconstructed to evaluate the accuracy of the calibration, and the measured mean error is 0.012 mm. A head phantom is reconstructed and tracked by the proposed optical surgical navigation system. The tracking error is less than 0.3 mm.

Conclusions

Experimental results show that the proposed method obtains high accessibility and accuracy and satisfies application requirements.
Microwave‐Assisted Biogenic Synthesis of Metal‐Decorated Reduced Graphene Oxide and their Electrochemical Properties.
Authors: Gannavarapu Krishna Prasad , Azizighannad Samar , Muthukumar Sai , Mitra Somenath , Dandamudi Rajesh Babu
Published: December 2018

Herein we report a microwave assisted, fungal (Ganoderma lucidum) extract mediated synthesis of noble metal decorated reduced graphene oxide(r‐GO). The carbon to oxygen ratio increased from 1.46 in GO to 2.72 in r‐GO. The electron rate transfer capabilities of Pt, Pd, Ru, Pt−Pd and Pt−Ru decorated r‐GO were tested in ferri‐ferro coupling reaction. Excellent electrochemical behaviour were observed in their ability to oxidize hydrazine, reduce H2O2, as well as oxygen reduction in alkaline medium and hydrogen evolution in acidic medium. These reactions represent diverse applications in energy production, storage, electrochemical sensing and electro catalysis, thus the method presented here can be quite useful in diverse applications.
(Ni,Co)Se2/NiCo‐LDH Core/Shell Structural Electrode with the Cactus‐Like (Ni,Co)Se2 Core for Asymmetric Supercapacitors
Authors: Li Xin , Wu Haijun , Guan Cao , Elshahawy Abdelnaby M. , Dong Yangtao , Pennycook Stephen J. , Wang John
Published: December 2018

Supercapacitors (SCs) have been widely studied as a class of promising energy‐storage systems for powering next‐generation E‐vehicles and wearable electronics. Fabricating hybrid‐types of electrode materials and designing smart nanoarchitectures are effective approaches to developing high‐performance SCs. Herein, first, a Ni‐Co selenide material (Ni,Co)Se2 with special cactus‐like structure as the core, to scaffold the NiCo‐layered double hydroxides (LDHs) shell, is designed and fabricated. The cactus‐like structural (Ni,Co)Se2 core, as a highly conductive and robust support, promotes the electron transport as well as hinders the agglomeration of LDHs. The synergistic contributions from the two types of active materials together with the superior properties of the cactus‐like nanostructure enable the (Ni,Co)Se2/NiCo‐LDH hybrid electrode to exhibit a high capacity of ≈170 mA h g−1 (≈1224 F g−1), good rate performance, and long durability. The as‐assembled (Ni,Co)Se2/NiCo‐LDH//PC (porous carbon) asymmetric supercapacitor (ASC) with an operating voltage of 1.65 V delivers a high energy density of 39 W h kg−1 at a power density of 1650 W kg−1. Therefore, the cactus‐like core/shell structure offers an effective pathway to engineer advanced electrodes. The assembled flexible ASC is demonstrated to effectively power electronic devices.
Ionic Liquid‐Controlled Growth of NiCo2S4 3D Hierarchical Hollow Nanoarrow Arrays on Ni Foam for Superior Performance Binder Free Hybrid Supercapacitors
Authors: Cui Yingxue , Zhang Jing , Jin Cen , Liu Yanxia , Luo Wenhao , Zheng Wenjun
Published: December 2018

A significant development in the design of a NiCo2S4 3D hierarchical hollow nanoarrow arrays (HNA)‐based supercapacitor binder free electrode assembled by 1D hollow nanoneedles and 2D nanosheets on a Ni foam collector through controlling ionic liquid 1‐octyl‐3‐methylimidazolium chloride ([OMIm]Cl) concentration is reported. The unique NiCo2S4‐HNA electrode acquires high specific capacity (1297 C g−1 at 1 A g−1, 2.59 C cm−2 at 2 mA cm−2), excellent rate capability (maintaining 73.0% at 20 A g−1), and long operational life (maintaining 92.4% after 10 000 cycles at 5 A g−1), which are superior to those for 1D hollow nanoneedle arrays (HNN) and 2D porous nanoflake arrays (PNF). The outstanding electrochemical performance is attributed to the novel 3D structure with large specific surface, hollow cores, high porosity as well as stable architecture. In addition, a hybrid supercapacitor applying 3D NiCo2S4‐HNA as the positive electrode and active carbon as the negative electrode exhibits a high energy density of 42.5 Wh kg−1 at a power density of 2684.2 W kg−1 in an operating voltage of 1.6 V. Robust cycling stability is also expressed with 84.9% retention after repeating 10 000 cycles at 5 A g−1, implying their great potential in superior‐performance supercapacitors.
Multifunctional Noncontact Micromanipulation Using Whirling Flow Generated by Vibrating a Single Piezo Actuator
Authors: Liu Xiaoming , Shi Qing , Lin Yuqing , Kojima Masaru , Mae Yasushi , Fukuda Toshio , Huang Qiang , Arai Tatsuo
Published: December 2018

A noncontact method that can achieve immobilization, transportation, and rotation in the microscale is desired in biological micromanipulation. A multifunctional noncontact micromanipulation method is proposed here based on a vibration‐generated whirling flow. Resonance of a cantilever structure is utilized to extend the straight vibration of a single piezo actuator to the 2D circular vibration of a micropipette. The circular vibration in fluids can generate the whirling flow featured with low pressure in the core area and flow velocity gradient. The low pressure can immobilize the objects nearby and transport them together with the micropipette, and the flow velocity gradient is utilized to form a torque to rotate the immobilized object. Experiments of the microbeads are conducted to evaluate the claimed functions and quantify the key parameters that influence the rotation velocity. The cell spheroid is immobilized and rotated for 3D observation, and by assessing the viability of the cells containing in the spheroid, the proposed method is proved noninvasive to living cells. Finally, another important application in operations of mouse egg cells is shown, which indicates that the proposed method is a potential valuable tool in biological micromanipulation.
The reported point centromeres of Scheffersomyces stipitis are retrotransposon long terminal repeats
Authors: Coughlan Aisling Y. , Wolfe Kenneth H.
Published: December 2018

Point centromeres, found in some ascomycete yeasts such Saccharomyces cerevisiae, are very different in structure from the centromeres of other eukaryotes. They are tiny and nonrepetitive and contain only two short conserved sequence motifs. Until recently, point centromeres were thought to have a single evolutionary origin, in the budding yeast family Saccharomycetaceae. Most yeasts outside this family have centromeres that are many kilobases in size. Some have centromeres consisting of a large inverted repeat sequence, others have centromeric clusters of retrotransposons, and a third group including Candida albicans has centromeres with no conserved sequence features. It was recently reported that Scheffersomyces stipitis has point centromeres with a strongly conserved 125‐bp core sequence, which is unexpected because S. stipitis is only distantly related to the known point‐centromere species. We show here that the 125‐bp core sequence is actually part of the long terminal repeat (LTR) of the Ty5‐like retrotransposon Tps5, which forms a cluster in the centromeric region of each S. stipitis chromosome. Thus, the LTR of a centromere‐associated retrotransposon confers centromere‐like mitotic stability when cloned into a plasmid. The centromeric regions of S. stipitis contain three types of Tps5 element (Tps5a, Tps5b, and Tps5c) and a noncoding nonautonomous large retrotransposon derivative.
Einleitung
Authors: Krimmer Holger
Published: December 2018

Der Datenreport Zivilgesellschaft bietet erstmals einen Überblick über Stand und Entwicklung von Zivilgesellschaft und bürgerschaftlichem Engagement auf verbindender Grundlage der ganzen Bandbreite vorliegender Erhebungsdaten zu diesen Themen. Ein solcher Zugang ist möglich geworden durch die Zusammenarbeit der entsprechenden Institutionen und Akteure im Forum Zivilgesellschaftsdaten (FZD). Das Forum ist Plattform und Netzwerk aller datenerhebenden Akteure in dem genannten Thema und wurde seit Mai 2016 bis Juli 2018 vom Bundesministerium für Familie, Senioren, Frauen und Jugend gefördert und von ZiviZ im Stifterverband organisiert.
Organisierte Zivilgesellschaft
Authors: Priemer Jana , Bischoff Antje , Hohendanner Christian , Krebstakies Ralf , Rump Boris , Schmitt Wolfgang
Published: December 2018

Warum benötigen wir empirische Daten zu Vereinen, Stiftungen und anderen gemeinnützigen Organisationen ? Der Großteil bürgerschaftlichen Engagements findet nach wie vor überwiegend in Vereinen und anderen Organisationen des Dritten Sektors statt. Sie bilden also einen organisationalen Rahmen für bürgerschaftliches Engagement (vgl. Abschnitt 4.8). Zudem leisten diese Organisationen vielfältige gesellschaftliche Beiträge.
2D Spatial Distributions for Measures of Random Sequences Using Conjugate Maps
Authors: Li Qingping , Zheng Jeffrey
Published: December 2018

Advanced visual tools are useful to provide additional information for modern information warfare. 2D spatial distributions of random sequences play an important role to understand properties of complex sequences. This chapter proposes time sequences from a given logical function of 1D cellular automata in both Poincare map and conjugate map. Multiple measure sequences of Markov chains can be used to display spatial distributions using conjugate maps. Measure sequences are recursively produced by different logical functions generating maps. Possible complementary feature exists between pair functions. Conjugate symmetry relationships between a pair of logical functions in conjugate maps can be observed.
Novel Pseudorandom Number Generation Using Variant Logic Framework
Authors: Zheng Jeffrey
Published: December 2018

Cybersecurity requires cryptology for the basic protection. Among different ECRYPT technologies, stream cipher plays a central role in advanced network security applications; in addition, pseudorandom number generators are placed in the core position of the mechanism. In this chapter, a novel method of pseudorandom number generation is proposed to take advantage of the large functional space described using variant logic, a new framework for binary logic. Using permutation and complementary operations on classical truth table to form relevant variant table, numbers can be selected from table entries having pseudorandom properties. A simple generation mechanism is described and shown, and pseudorandom sequences are analyzed for their cycle property and complexity. Applying this novel method, it can play a useful role in future applications for higher performance of cybersecurity environments.
Meta Model on Concept Cell
Authors: Zheng Jeffrey , Zheng Chris
Published: December 2018

Applying network topology schemes, two types of three levels of meta knowledge representations have been established. This chapter proposes a meta model on concept cell that provides a meta organisation of knowledge in natural and artificial intelligent systems structurally.
Two-current correlations in the pion on the lattice
Authors: Bali Gunnar S. , Bruns Peter C. , Castagnini Luca , Diehl Markus , Gaunt Jonathan R. , Gläßle Benjamin , Schäfer Andreas , Sternbeck André , Zimmermann Christian
Published: December 2018

Abstract

We perform a systematic study of the correlation functions of two quark currents in a pion using lattice QCD. We obtain good signals for all but one of the relevant Wick contractions of quark fields. We investigate the quark mass dependence of our results and test the importance of correlations between the quark and the antiquark in the pion. Our lattice data are compared with predictions from chiral perturbation theory.
Modular flow as a disentangler
Authors: Chen Yiming , Dong Xi , Lewkowycz Aitor , Qi Xiao-Liang
Published: December 2018

Abstract

In holographic duality, the entanglement entropy of a boundary region is proposed to be dual to the area of an extremal codimension-2 surface that is homologous to the boundary region, known as the Hubeny-Rangamani-Takayanagi (HRT) surface. In this paper, we study when the HRT surfaces of two boundary subregions R, A are in the same Cauchy slice. This condition is necessary for the subregion-subregion mapping to be local for both subregions and for states to have a tensor network description. To quantify this, we study the area of a surface that is homologous to A and is extremal except at possible intersections with the HRT surface of R (minimizing over all such possible surfaces), which we call the constrained area. We give a boundary proposal for an upper bound of this quantity, a bound which is saturated when the constrained surface intersects the HRT surface of R at a constant angle. This boundary quantity is the minimum entropy of region A in a modular evolved state — a state that has been evolved unitarily with the modular Hamiltonian of R. We can prove this formula in two boundary dimensions or when the modular Hamiltonian is local. This modular minimal entropy is a boundary quantity that probes bulk causality and, from this quantity, we can extract whether two HRT surfaces are in the future or past of each other. These entropies satisfy some inequalities reminiscent of strong subadditivity and can be used to remove certain corner divergences.
Probing pseudo Nambu-Goldstone boson dark matter at loop level
Authors: Ishiwata Koji , Toma Takashi
Published: December 2018

Abstract

In the standard model extended by a single complex scalar boson with a softly broken global U(1) symmetry, a pseudo Nambu-Goldstone boson becomes a candidate for dark matter. In this paper, we discuss the direct detection of the pseudo Nambu-Goldstone boson dark matter. Since the tree-level amplitude for dark matter-nucleon scattering vanishes, higher order quantum corrections for the amplitude should be taken into account. We perform the calculation at the next-to-leading order in QCD in a systematic manner.
Modular Hamiltonians and large diffeomorphisms in AdS3
Authors: Das Suchetan , Ezhuthachan Bobby
Published: December 2018

Abstract

We generalize the work of Kabat and Lifshytz (arXiv:1703.06523), of reconstructing bulk scalar fields using the intersecting modular Hamiltonian approach discussed therein, to any locally AdS3 space related to AdS3 by large diffeomorphisms. We present several checks for our result including matching with their result in appropriate limits as well as consistency with bulk diffeomorphisms. As a further check, from our expressions we also compute the first correction due to gravitational dressing to the bulk scalar field in AdS3 and match with known results in the literature.
Numerical Prediction of the Microstructure and Stress Evolution During Surface Grinding of AISI 52100 (DIN 100Cr6)
Authors: Rajaei Ali , Hallstedt Bengt , Broeckmann Christoph , Barth Sebastian , Trauth Daniel , Bergs Thomas
Published: December 2018

Grinding is one of the most important finishing processes in industrial production. During grinding, the workpiece is subjected to thermomechanical loads. Thermal damage can occur in terms of microstructure changes due to a critical temperature history. A holistic model of the relevant physical load fields and their interactions would help describe and predict the influence of grinding loads on the residual stresses in the surface zone of the workpiece. In this paper, a very promising approach is introduced to simulate grinding of the hardened and tempered bearing steel AISI 52100 using the Finite Element Method (FEM). A material model was developed to describe the thermomechanical and metallurgical changes of the bearing steel under the process loads. Material properties were modeled depending on the temperature and microstructure changes. Temperature gradients, microstructure evolution, thermal, and phase transformation strains were integrated in the model to predict the residual stress state after grinding. Experimental and simulative investigations were conducted for pendulum grinding, and the measured and simulated residuals stresses were compared. The depth of the subsurface zone, where thermally influenced microstructural changes occur, varied with changes of the process parameters. Experiments and simulations showed compressive stresses in the re-hardened zone and tensile stresses in the tempered area.
Digital Content Marketing's Role in Fostering Consumer Engagement, Trust, and Value: Framework, Fundamental Propositions, and Implications
Authors: Hollebeek Linda D. , Macky Keith
Published: December 2018

In a landscape of growing online consumer/firm interactions, digital content marketing (DCM) which aims to foster consumers’ brand engagement and trust, is on the rise. However, despite significant practitioner interest, academic DCM research is lagging, resulting in an important knowledge gap. Based on an extensive review, we conceptualize DCM as the creation and dissemination of relevant, valuable brand-related content to current or prospective customers on digital platforms to develop their favorable brand engagement, trust, and relationships (vs. directly persuading consumers to purchase). We also develop a conceptual framework that identifies important consumer-based DCM antecedents, including uses-and-gratifications (U&G)-informed functional, hedonic, and authenticity-based motives for DCM interactions. DCM's first-tier, intra-interaction consequences include consumers’ cognitive, emotional, and behavioral engagement that foster brand-related sense-making, identification, and citizenship behaviors, respectively. These in turn trigger DCM's second-tier, extra-interaction consequences of brand trust and attitude, which successively contribute to the development of DCM's third-tier, value-based consequences of consumer and firm-based brand equity. We summarize our findings in a set of Fundamental Propositions (FPs) of DCM and conclude by deriving key implications from our analyses.
Evaluation of the Efficacy of Psychological Interventions in Promoting Preparedness to Armed Conflicts – A Randomized Controlled Study
Authors: Bodas Moran , Siman-Tov Maya , Kreitler Shulamith , Peleg Kobi
Published: December 2018

Objective

Despite efforts by civil defense authorities, levels of households’ preparedness to emergencies remain insufficient in many countries. Engaging the public in preparedness behavior is a challenge worldwide. The purpose of this study was to explore the efficacy of psychological intervention in promoting preparedness behavior to armed conflicts in Israel.

Methods

A randomized controlled trial (N = 381) with two control groups and three intervention groups was used. The psychological interventions studied were elevated threat perception, external reward, and manipulation of a cognitive cluster related to preparedness.

Results

The results of the analysis suggest a significant effect of intervention on the increase of reported preparedness (F4,375= 4.511,P= 0.001). The effect is attributed to the intervention group in which external reward was offered. Participants in this group were about two times more likely to report greater levels of preparedness compared to the control group (RR = 1.855; 95% CI: 1.065, 3.233).

Conclusions

The findings suggest that preparedness behavior can be promoted through external incentives. These are presumably effective motivators because they encourage preparedness while allowing subjects to retain their denial as an adaptive coping mechanism. Innovative thinking is required to overcome the psychological barriers associated with public reluctance to engage in preparedness. (Disaster Med Public Health Preparedness. 2018;13:713–723)
Active Shooter and Terrorist Event-Related Posttraumatic Stress and Depression: Television Viewing and Perceived Safety
Authors: Fullerton Carol S. , Mash Holly B. Herberman , Morganstein Joshua C. , Ursano Robert J.
Published: December 2018

Objective

This study examined the relationship of sniper-related television viewing (TV) and perceived safety to posttraumatic stress (PTS) and depressive symptoms during the Washington, DC sniper attacks.

Methods

Participants were 1238 Washington, DC area residents assessed using an internet survey including the Impact of Event Scale-Revised, Patient Health Questionnaire-9, hours of TV, and perceived safety.

Results

Almost 40% (n = 459) of participants watched at least 2 hours of sniper-related TV daily. TV viewing was associated with lower total perceived safety. After adjusting for demographics, more TV viewing and decreased perceived safety were related to increased PTS and depressive symptoms. TV viewing modified the effect of safety on PTS and depressive symptoms. Among participants with low and high perceived safety, hours of TV were positively associated with PTS; however, the effect was stronger among those with low perceived safety. The relationship of TV to increased depressive symptoms was identified only in participants who reported low perceived safety.

Conclusions

The influence of media exposure and perceived safety have implications for intervention by community leaders and mental health care providers. Recommendations include limiting media exposure during a terrorist event, particularly among those who perceive that their safety is at risk, and targeting safety in communication strategies. (Disaster Med Public Health Preparedness. 2019;13:570-576)
Making the Countryside Global: The Bucharest School of Sociology and International Networks of Knowledge
Authors: Muşat Raluca
Published: December 2018

The interwar period was a time when the rural world gained new prominence in visions of modernity and modernisation across the world. The newly reconfigured countries of Eastern Europe played a key role in focusing attention on the countryside as an important area of state intervention. This coincided with a greater involvement of the social sciences in debates and in projects of development and modernisation, both nationally and internationally. This article examines the contribution of the Bucharest School of Sociology to the creation of an idea of ‘the global countryside’ that emerged in the interwar years and only matured in the post-war period.
Die „schwer erziehbaren Kinder“ benötigten dringend einen Arzt – verbandspolitische Vorgeschichte der Einführung des Facharzttitels für Kinder- und Jugendpsychiatrie in Deutschland 1968
Authors: Schepker Klaus , Harsch Daniela , Fegert Jörg M.
Published: December 2018

Zusammenfassung. In den Jahren nach 1945 war die entstehende Kinder- und Jugendpsychiatrie in Deutschland noch nicht eigenständig, sondern personell und organisatorisch Teil der gesamten Nervenheilkunde. Das vorrangige fachpolitische Ziel deren führender Vertreter aus der (Erwachsenen-)Psychiatrie war der Erhalt des „Machtbereiches“ der gesamten Nervenheilkunde als Einheit von Neurologie und Psychiatrie. Interessen von „kleinen Psycho-Fächern“ wie der Kinder- und Jugendpsychiatrie, Psychotherapie wurden dabei als nachrangig betrachtet. Als Perspektive für diese Fächer wurden primär Zusatzqualifikationen und Zusatzbezeichnungen zum Facharzt Nervenheilkunde erwogen. In vielen Industrienationen erfolgte ein Ausbau der Kinder- und Jugendpsychiatrie um besser mit den „Schwierigkeiten“ umzugehen, die „schwierige Kinder haben und machen“. Bedingt durch Säuberung und Gleichschaltung des Fürsorge- und Gesundheitswesens im Nationalsozialismus und die Kriegsfolgen erfolgte der Ausbau der kinder- und jugendpsychiatrischen Versorgung in der Bundesrepublik unter besonderen Rahmenbedingungen und es fehlten (Fach-)Ärzte für diese „soziale Aufgabe“. Interessenskonflikte führender Jugendpsychiater als Repräsentanten der gesamten Nervenheilkunde hemmten eine eigenständige Entwicklung. Erst nachdem die Kernfrage der Trennung von Neurologie und Psychiatrie durch den Kompromiss der Einführung von drei Facharzttiteln (Psychiatrie, Neurologie, Nervenheilkunde) gelöst wurde, wurde auf dem Ärztetag 1968 die Einführung der Gebietsbezeichnung Kinder- und Jugendpsychiatrie beschlossen.
Structure and Metamorphism of Markam Gneiss Dome From the Eastern Tibetan Plateau and Its Implications for Crustal Thickening, Metamorphism, and Exhumation
Authors: Zhao Z. B. , Du J. X. , Liang F. H. , Wu C. , Liu X. J.
Published: December 2018

Gneiss domes developed in the eastern Songpan‐Ganzi Flysch (SGF) belt, located in the hinterland of the Longmen Shan Thrust belt of the eastern Tibetan Plateau. These domes have similar pressure‐temperature (denoted as P‐T below) paths and formed during Late Triassic‐Early Jurassic. One of them, the Markam Gneiss Dome (MGD), is cored by granite and is mantled by a metaturbidite aureole. Our structural observations show top‐to‐the‐south shearing that transposed an upright S1 foliation into a flat‐lying NW‐SE striking S2 composite foliation in the Triassic metaturbidites. Thin sections reveal that the metamorphic index minerals biotite, garnet, and staurolite grew prior to the transposition into S2, whereas kyanite and sillimanite crystallized syn‐S2 development. P‐T pseudosections for the metaturbidites indicate a temperature peak of approximately 618–632 °C and a pressure peak of approximately 6–8 kbar. The highest P‐T condition was immediately followed by isothermal decompression, which is represented by the sillimanite overgrowing andalusite and biotite. Granite was emplaced at ~10‐ to 15‐km depth, during isothermal decompression. Zircon U‐Pb geochronology of metaturbidites, granite, and pegmatite of the MGD indicates that (1) the metaturbidites are younger than 240 Ma, (2) the granite was mainly sourced from the metaturbidites, and (3) deformation leading to the transposition of S1 into S2 mainly occurred ca. 215–170 Ma. Our new P‐T‐D‐t results from the MGD confirm those of other gneiss domes in the SGF and indicate Late Triassic‐Early Jurassic crustal shortening and thickening that probably reflects coeval low‐viscosity crustal flow of the SGF.
A Statistical Study on the Properties of Dips Ahead of Dipolarization Fronts Observed by MMS
Authors: Schmid D. , Volwerk M. , Plaschke F. , Nakamura R. , Baumjohann W. , Wang G. Q. , Wu M. Y. , Zhang T. L.
Published: December 2018

Magnetic reconnection in the magnetotail accelerates plasma in short‐duration bursts of fast flows, referred to as bursty bulk flows toward the Earth. These bursty bulk flows are typically accompanied by a sharp increase in the northward magnetic field component, the so‐called dipolarization front (DF). This rapid increase in northward magnetic field is often preceded by a decrease, the so called DF‐dip, where the northward magnetic field component sometimes even changes sign and turns southward. Here we present a statistical study of the DF‐dip of 43 events, using observations from the Magnetospheric Multiscale (MMS) mission during summer 2017, when MMS's apogee was located in the magnetotail around 25 RE. The 43 events are subdivided into two categories according to their DF‐dip: 20 events where the DF‐dip stays northward (positive DF‐dip category) and 23 events where the DF‐dip turns fully southward (negative DF‐dip category). We find that (1) the magnetic field depression ahead of the DF of the positive DF‐dip events correlates mainly with perpendicular currents and diamagnetic currents flowing ahead of the DF and (2) the magnetic field depression ahead of the DF of the negative DF‐dip events correlates mainly with field‐aligned currents and that this type of events might be (a) earthward moving flux rope‐like structures caused by multiple X‐line reconnection and/or (b) are a result of localized, single X‐line reconnection under a guide field.
Temporal Characteristic of the Mesoscale Plasma Flow Perturbations in the High‐Latitude Ionosphere
Authors: Chen Yun‐Ju , Heelis Roderick A.
Published: December 2018

Spatial and temporal characteristics of flow perturbations in the high‐latitude ionosphere are important considerations for energy deposition from the magnetosphere. In this study, we examine the temporal characteristics of plasma flow perturbations with spatial scales between 100 and 400 km from two consecutive Defense Meteorological Satellite Program (DMSP) passes that have about the same orbital plane and sample time spacing between a few seconds and 20 min during local summer seasons in 2007‐2015. The temporal characteristics of mesoscale flow perturbations are described by rise and saturation times for growth and decay derived from the changes in magnitude of perturbations and the time separation between consecutive samples. Observations suggest that the rise times for both growth and decay are shorter for small spatial scales (1–2 min, 100–200 km) and longer for large spatial scales (3–5 min, 200–400 km). The saturation time for decay is ~10 min for small scales and ~20 min for large scales. The growth saturation time is about 5–10 min for both scale sizes. These characteristic times for growth are always shorter than the decay times. If the difference in these characteristic times between growth and decay is produced by motion of a perturbation with the background flow through the observed volume, then a longitudinal scale size of 750 km or 1.5 hr of local time is implied.
Earthquake Nucleation Size: Evidence of Loading Rate Dependence in Laboratory Faults
Authors: Guérin‐Marthe Simon , Nielsen Stefan , Bird Robert , Giani Stefano , Di Toro Giulio
Published: December 2018

Recent Global Positioning System observations of major earthquakes such as the 2014 Chile megathrust show a slow preslip phase releasing a significant portion of the total moment (Ruiz et al., 2014, https://doi.org/10.1126/science.1256074). Despite advances from theoretical stability analysis (Rubin & Ampuero, 2005, https://doi.org/10.1029/2005JB003686; Ruina, 1983, https://doi.org/10.1029/jb088ib12p10359) and modeling (Kaneko et al., 2017, https://doi.org/10.1002/2016GL071569), it is not fully understood what controls the prevalence and the amount of slip in the nucleation process. Here we present laboratory observations of slow slip preceding dynamic rupture, where we observe a dependence of nucleation size and position on the loading rate (laboratory equivalent of tectonic loading rate). The setup is composed of two polycarbonate plates under direct shear with a 30‐cm long slip interface. The results of our laboratory experiments are in agreement with the preslip model outlined by Ellsworth and Beroza (1995, https://doi.org/10.1126/science.268.5212.851) and observed in laboratory experiments (Latour et al., 2013, https://doi.org/10.1002/grl.50974; Nielsen et al., 2010, https://doi.org/10.1111/j.1365-246x.2009.04444.x; Ohnaka & Kuwahara, 1990, https://doi.org/10.1016/0040-1951(90)90138-X), which show a slow slip followed by an acceleration up to dynamic rupture velocity. However, further complexity arises from the effect of (1) rate of shear loading and (2) inhomogeneities on the fault surface. In particular, we show that when the loading rate is increased from 10−2 to 6 MPa/s, the nucleation length can shrink by a factor of 3, and the rupture nucleates consistently on higher shear stress areas. The nucleation lengths measured fall within the range of the theoretical limits Lb and
derived by Rubin and Ampuero (2005, https://doi.org/10.1029/2005JB003686) for rate‐and‐state friction laws.
Merging of Storm Time Midlatitude Traveling Ionospheric Disturbances and Equatorial Plasma Bubbles
Authors: Aa Ercha , Zou Shasha , Ridley Aaron , Zhang Shunrong , Coster Anthea J. , Erickson Philip J. , Liu Siqing , Ren Jiaen
Published: December 2018

Postsunset midlatitude traveling ionospheric disturbances (TIDs) and equatorial plasma bubbles (EPBs) were simultaneously observed over American sector during the geomagnetic storm on 8 September 2017. The characteristics of TIDs are analyzed by using a combination of the Millstone Hill incoherent scatter radar data and 2‐D detrended total electron content (TEC) from ground‐based Global Navigation Satellite System receivers. The main results associated with EPBs are as follows: (1) stream‐like structures of TEC depletion occurred simultaneously at geomagnetically conjugate points, (2) poleward extension of the TEC irregularities/depletions along the magnetic field lines, (3) severe equatorial and midlatitude electron density (Ne) bite outs observed by Defense Meteorological Satellite Program and Swarm satellites, and (4) enhancements of ionosphere F layer virtual height and vertical drifts observed by equatorial ionosondes near the EPBs initiation region. The stream‐like TEC depletions reached 46° magnetic latitudes that map to an apex altitude of 6,800 km over the magnetic equator using International Geomagnetic Reference Field. The formation of this extended density depletion structure is suggested to be due to the merging between the altitudinal/latitudinal extension of EPBs driven by strong prompt penetration electric field and midlatitude TIDs. Moreover, the poleward portion of the depletion/irregularity drifted westward and reached the equatorward boundary of the ionospheric main trough. This westward drift occurred at the same time as the sudden expansion of the convection pattern and could be attributed to the strong returning westward flow near the subauroral polarization stream region. Other possible mechanisms for the westward tilt are also discussed.
miR-100 maintains phenotype of tumor-associated macrophages by targeting mTOR to promote tumor metastasis via Stat5a/IL-1ra pathway in mouse breast cancer
Authors: Wang Wei , Liu Yan , Guo Jian , He Huiwen , Mi Xue , Chen Chong , Xie Junling , Wang Shengnan , Wu Peng , Cao Fengqi , Bai Lipeng , Si Qin , Xiang Rong , Luo Yunping
Published: December 2018

Tumor-associated macrophages (TAMs), the main part of immune cells in tumor microenvironment (TME), play a potent role in promoting tumorigenesis through mechanisms such as stimulating angiogenesis, enhancing tumor migration and suppressing antitumor immunity. MicroRNAs (miRNAs) are considered as crucial regulators in multiple biological processes. The relationship between miRNAs and macrophages function has been extensively reported, but the roles that miRNAs play in regulating TAMs phenotype remain unclear. In this study, we screened highly expressed microRNAs in TAMs, and first identified that miR-100 represented a TAMs-high expression pattern and maintained TAMs phenotype by targeting mTOR signaling pathway. Moreover, miR-100 expression level in TAMs was positively related to IL-1ra secretion, a traditional immune-suppressive cytokine, which was determined to promote tumor cells stemness via stimulating Hedgehog pathway. Mechanism study suggested that mTOR/Stat5a pathway was involved in IL-1ra transcriptional regulation process mediated by miR-100. More importantly, tumor metastasis and invasion capacity were significantly decreased in a 4T1 mouse breast cancer model injected intratumorally with miR-100 antagomir, and combination therapy with cisplatin showed much better benefit. In this study, we confirm that highly expressed miR-100 maintains the phenotype of TAMs and promotes tumor metastasis via enhancing IL-1ra secretion. Interfering miR-100 expression of TAMs in mouse breast cancer model could inhibit TAMs pro-tumor function and reduce tumor metastasis, which suggests that miR-100 could serve as a potential therapy target to remodel tumor microenvironment in breast cancer.
A virus-encoded type I interferon decoy receptor enables evasion of host immunity through cell-surface binding
Authors: Hernáez Bruno , Alonso-Lobo Juan Manuel , Montanuy Imma , Fischer Cornelius , Sauer Sascha , Sigal Luis , Sevilla Noemí , Alcamí Antonio
Published: December 2018

Soluble cytokine decoy receptors are potent immune modulatory reagents with therapeutic applications. Some virus-encoded secreted cytokine receptors interact with glycosaminoglycans expressed at the cell surface, but the biological significance of this activity in vivo is poorly understood. Here, we show the type I interferon binding protein (IFNα/βBP) encoded by vaccinia and ectromelia viruses requires of this cell binding activity to confer full virulence to these viruses and to retain immunomodulatory activity. Expression of a variant form of the IFNα/βBP that inhibits IFN activity, but does not interact with cell surface glycosaminoglycans, results in highly attenuated viruses with a virulence similar to that of the IFNα/βBP deletion mutant viruses. Transcriptomics analysis and infection of IFN receptor-deficient mice confirmed that the control of IFN activity is the main function of the IFNα/βBP in vivo. We propose that retention of secreted cytokine receptors at the cell surface may largely enhance their immunomodulatory activity.
Geometric quenching of orbital pair breaking in a single crystalline superconducting nanomesh network
Authors: Nam Hyoungdo , Chen Hua , Adams Philip W. , Guan Syu-You , Chuang Tien-Ming , Chang Chia-Seng , MacDonald Allan H. , Shih Chih-Kang
Published: December 2018

In a superconductor Cooper pairs condense into a single state and in so doing support dissipation free charge flow and perfect diamagnetism. In a magnetic field the minimum kinetic energy of the Cooper pairs increases, producing an orbital pair breaking effect. We show that it is possible to significantly quench the orbital pair breaking effect for both parallel and perpendicular magnetic fields in a thin film superconductor with lateral nanostructure on a length scale smaller than the magnetic length. By growing an ultra-thin (2 nm thick) single crystalline Pb nanowire network, we establish nm scale lateral structure without introducing weak links. Our network suppresses orbital pair breaking for both perpendicular and in-plane fields with a negligible reduction in zero-field resistive critical temperatures. Our study opens a frontier in nanoscale superconductivity by providing a strategy for maintaining pairing in strong field environments in all directions with important technological implications.
The open-ocean missing backscattering is in the structural complexity of particles
Authors: Organelli Emanuele , Dall’Olmo Giorgio , Brewin Robert J. W. , Tarran Glen A. , Boss Emmanuel , Bricaud Annick
Published: December 2018

Marine microscopic particles profoundly impact global biogeochemical cycles, but our understanding of their dynamics is hindered by lack of observations. To fill this gap, optical backscattering measured by satellite sensors and in-situ autonomous platforms can be exploited. Unfortunately, these observations remain critically limited by an incomplete mechanistic understanding of what particles generate the backscattering signal. To achieve this understanding, optical models are employed. The simplest of these models—the homogeneous sphere—severely underestimates the measured backscattering and the missing signal has been attributed to submicron particles. This issue is known as the missing backscattering enigma. Here we show that a slightly more complex optical model—the coated sphere—can predict the measured backscattering and suggests that most of the signal comes from particles >1 µm. These findings were confirmed by independent size-fractionation experiments. Our results demonstrate that the structural complexity of particles is critical to understand open-ocean backscattering and contribute to solving the enigma.
An electrogenic redox loop in sulfate reduction reveals a likely widespread mechanism of energy conservation
Authors: Duarte Américo G. , Catarino Teresa , White Gaye F. , Lousa Diana , Neukirchen Sinje , Soares Cláudio M. , Sousa Filipa L. , Clarke Thomas A. , Pereira Inês A. C.
Published: December 2018

The bioenergetics of anaerobic metabolism frequently relies on redox loops performed by membrane complexes with substrate- and quinone-binding sites on opposite sides of the membrane. However, in sulfate respiration (a key process in the biogeochemical sulfur cycle), the substrate- and quinone-binding sites of the QrcABCD complex are periplasmic, and their role in energy conservation has not been elucidated. Here we show that the QrcABCD complex of Desulfovibrio vulgaris is electrogenic, as protons and electrons required for quinone reduction are extracted from opposite sides of the membrane, with a H+/e− ratio of 1. Although the complex does not act as a H+-pump, QrcD may include a conserved proton channel leading from the N-side to the P-side menaquinone pocket. Our work provides evidence of how energy is conserved during dissimilatory sulfate reduction, and suggests mechanisms behind the functions of related bacterial respiratory complexes in other bioenergetic contexts.
Ezh2 programs TFH differentiation by integrating phosphorylation-dependent activation of Bcl6 and polycomb-dependent repression of p19Arf
Authors: Li Fengyin , Zeng Zhouhao , Xing Shaojun , Gullicksrud Jodi A. , Shan Qiang , Choi Jinyong , Badovinac Vladimir P. , Crotty Shane , Peng Weiqun , Xue Hai-Hui
Published: December 2018

Ezh2 is an histone methyltransferase (HMT) that catalyzes H3K27me3 and functions in TH1, TH2, and Treg cells primarily via HMT activity. Here we show that Ezh2 ablation impairs T follicular helper (TFH) cell differentiation and activation of the TFH transcription program. In TFH cells, most Ezh2-occupied genomic sites, including the Bcl6 promoter, are associated with H3K27ac rather than H3K27me3. Mechanistically, Ezh2 is recruited by Tcf1 to directly activate Bcl6 transcription, with this function requiring Ezh2 phosphorylation at Ser21. Meanwhile, Ezh2 deploys H3K27me3 to repress Cdkn2a expression in TFH cells, where aberrantly upregulated p19Arf, a Cdkn2a protein product, triggers TFH cell apoptosis and antagonizes Bcl6 function via protein-protein interaction. Either forced expression of Bcl6 or genetic ablation of p19Arf in Ezh2-deficient cells improves TFH cell differentiation and helper function. Thus, Ezh2 orchestrates TFH-lineage specification and function maturation by integrating phosphorylation-dependent transcriptional activation and HMT-dependent gene repression.
Serine synthesis through PHGDH coordinates nucleotide levels by maintaining central carbon metabolism
Authors: Reid Michael A. , Allen Annamarie E. , Liu Shiyu , Liberti Maria V. , Liu Pei , Liu Xiaojing , Dai Ziwei , Gao Xia , Wang Qian , Liu Ying , Lai Luhua , Locasale Jason W.
Published: December 2018

Phosphoglycerate dehydrogenase (PHGDH) catalyzes the committed step in de novo serine biosynthesis. Paradoxically, PHGDH and serine synthesis are required in the presence of abundant environmental serine even when serine uptake exceeds the requirements for nucleotide synthesis. Here, we establish a mechanism for how PHGDH maintains nucleotide metabolism. We show that inhibition of PHGDH induces alterations in nucleotide metabolism independent of serine utilization. These changes are not attributable to defects in serine-derived nucleotide synthesis and redox maintenance, another key aspect of serine metabolism, but result from disruption of mass balance within central carbon metabolism. Mechanistically, this leads to simultaneous alterations in both the pentose phosphate pathway and the tri-carboxylic acid cycle, as we demonstrate based on a quantitative model. These findings define a mechanism whereby disruption of one metabolic pathway induces toxicity by simultaneously affecting the activity of multiple related pathways.
Broadband single molecule SERS detection designed by warped optical spaces
Authors: Mao Peng , Liu Changxu , Favraud Gael , Chen Qiang , Han Min , Fratalocchi Andrea , Zhang Shuang
Published: December 2018

Engineering hotspots is of crucial importance in many applications including energy harvesting, nano-lasers, subwavelength imaging, and biomedical sensing. Surface-enhanced Raman scattering spectroscopy is a key technique to identify analytes that would otherwise be difficult to diagnose. In standard systems, hotspots are realised with nanostructures made by acute tips or narrow gaps. Owing to the low probability for molecules to reach such tiny active regions, high sensitivity is always accompanied by a large preparation time for analyte accumulation which hinders the time response. Inspired by transformation optics, we introduce an approach based on warped spaces to manipulate hotspots, resulting in broadband enhancements in both the magnitude and volume. Experiments for single molecule detection with a fast soaking time are realised in conjunction with broadband response and uniformity. Such engineering could provide a new design platform for a rich manifold of devices, which can benefit from broadband and huge field enhancements.