bluuebunny/crossref_metadata_2025 huggingface dataset:
Interfacial Structure of Metastable 4H-BaRuO3 Thin Film on (111) SrTiO3 Substrate
Authors: Ding Q , Tian W , Lee M K , Eom E B , Pan X Q
Published: July 2020

BaRuO3 chemically belongs to ARuO3 family. It has unique hexagonal structure rather than an orthorhombic GdFeO3-type structure of other members, such as SrRuO3 and CaRuO3. The structure of ARuO3 compounds can be described on the basis of the close-packed stacking of AO3 layers in which the center of oxygen octahedra is occupied by ruthenium. A number of polymorph structures exist by mixing the cubic and hexagonal close-packed stacking of AO3 layers.

Up to date, only three polymorph structures have been observed in BaRuO3 bulk materials, which are denoted by 4H, 6H and 9R structure. The 9R structure (Fig. 1 (a)) is most stable at 1100 °C at atmosphere pressure. As pressure is increased, the 9R structure will transform through metastable 4H structure (Fig. 1(b)) to metastable 6H structure. The physical properties of BaRu03 polymorphs differ significantly with the variation of the structure. Hence, it is desirable to form phase pure polymorphs of BaRuO3 to examine the structure-property relationship.
Silicon Wafer Bonding: Effect of Wafer Surface Treatment on Interface Structure and Chemistry
Authors: Cox MJ , Kim MJ , Xu Hong , Carpenter RW
Published: July 2020

The two most important characteristics of any surface considered for wafer bonding are cleanliness, surface smoothness and macroscopic flatness. Silicon wafers in the as-received condition have a native oxide on the surface several nanometers thick [1], Figure la shows that they also have a layer of hydrocarbons. While they are not clean, they are smooth. Our wafers were plasma or ion cleaned, chemically treated, and ultra high vacuum (UHV) thermal desorption annealed in different combinations to find the best method for providing smooth, contamination free substrates that will produce an atomically flat, chemically clean Si/Si bonded interface.

The first approach was a single step process to remove the contaminants and then bond the clean wafers. Cleaning was accomplished by ion bombardment of the surface in an UHV chamber with base pressure 1x109 Torr. This ion cleaning chamber is connected between the UHV (2x10-10 ) bonding chamber and UHV (1x10-10) analysis chamber, allowing wafers to be cleaned, analyzed, and bonded without breaking vacuum [2].
HRTEM Image Simulations for Gate Oxide Metrology
Authors: Taylor S , Mardinly J , O'Keefe MA , Gronsky R
Published: July 2020

High resolution transmission electron microscopy (HRTEM) has found extensive use in the semiconductor industry for performing device metrology and characterization. However, shrinking device dimensions (gate oxides are rapidly approaching 10Å) present challenges to the use of HRTEM for many applications, including gate oxide metrology. In this study, we performed HRTEM image simulations of a MOSFET device to examine the accuracy of HRTEM in measuring gate oxide thickness. Length measurements extracted from simulated images were compared to actual dimensions in the model structure to assess TEM accuracy. The effects of specimen tilt, specimen thickness, objective lens defocus and coefficient of spherical aberration (CS) on measurement accuracy were explored for nominal 10Å and 16Å gate oxide thicknesses.

The gate oxide was modeled as an amorphous silicon oxide situated between a gate electrode and substrate, both modeled as single crystal Si(100). Image simulations of the sandwich structure were performed in cross-section (with Si[110] parallel to beam direction) using the multislice approximation for a 200 kV microscope with Cs=0.5mm.
Real Time Observations of Nanopipe Formation, Dislocation Motion and Nitrogen Desorption in GaN
Authors: Bailey GW , McKernan S , Price RL , Walck SD , Charest P-M , Gauvin R , Stach EA , Kisielowski CF , Wong WS , Sands T , Cheung NW
Published: July 2020

GaN and related wide band gap semiconductor alloys have received considerable attention over the past several years because of their utility in short wavelength opto-electronic and high power / high frequency devices. In most cases, GaN alloys are grown heteroepitaxially on (0001) single crystal sapphire. Due to the high lattice mismatch between GaN and sapphire, typical dislocation densities in these films vary from as high as 1010 cm-2 to, at best, 108 cm-2. Hollow core dislocations - also known as nanopipes - are also frequently observed. The presence of high defect densities is widely believed to limit the performance of GaN based electronic devices, especially the lifetime of commercially important blue and green laser diodes.

In this work, we present real time, in-situ TEM observations of the formation mechanism of nanopipes in single crystal GaN.
Effects of Confinement on Arborescent Graft Polystyrene Particle Shape
Authors: Chou TM , Aitouchen A , Libera M , Briber RM , Gauthier M
Published: July 2020

Arborescent graft polymers are highly branched materials synthesized by grafting multiple generations of macromolecular precursors on a central core [1,2]. They can be synthesized with controllable size and molecular weight depending on the number of generations and the precursor molecular weight. They possess many of the unique structural [3], thermodynamic, and rheological [4] properties of dendrimers but do so on a length scale roughly one order of magnitude higher. This research describes the effect of confinement on the shape of arborescent graft polystyrene (PS).

This work used 3rd generation arborescent graft PS synthesized with 5kg/mole linear polystyrene precursor (G3- 5K). The G3-5K PS sample was mixed to a dilution of approximately 0.005 wt% in toluene. A single drop of solution was placed on either a holey-carbon film or an ultrathin continuous carbon film. The solvent was evaporated under ambient conditions. A Philips CM20 FEG TEM/STEM equipped with a Gatan 666 PEELS and a 679 multiscan CCD camera was used to study the structure of these specimens.
Quantitative Transmission Electron Microtomography of Complex Bicontinuous Polymer Nanostructures
Authors: Spontak RJ , Jinnai H , Braunfeld MB , Agard DA
Published: July 2020

Nanostructured polymers constitute an increasingly important class of materials. Investigations into the formation of nanostructural elements in microphase-ordered block copolymers have elucidated universal mechanisms of self-organization in soft-condensed matter, since topologically comparable nanostructures develop in biological and surfactant systems. Emerging applications of such polymers include nanotemplates for inorganic materials, optical switches and nanoreactors. Despite all the efforts that have focused on these materials in previous years, basic questions regarding the characteristics of these nanostructures, especially those exhibiting bicontinuity, persist. While most attempts to address these questions have relied on small-angle scattering, a real-space approach to this problem compares slices of simulated nanostructures to 2-D transmission electron microscopy (TEM) images. An alternate strategy is transmission electron microtomography (TEMT), which utilizes 3-D images (reconstructed from a series of 2-D images collected at sequential tilt angles) for detailed structural analysis. Using this method, we have, for instance, recently confirmed that packing frustration,
Development of a 1MV-Field-Emission Electron Microscope II. Performance
Authors: Kawasaki T , Yoshida T , Gorai M , Akashi T , Matsui I , Furutsu T , Kamimura O , Matsuda T , Osakabe N , Tonomura A , Kitazawa K
Published: July 2020

The development of increasingly coherent and penetrating electron beams in electron microscopy will hasten progress in such fields as high resolution imaging, electron holography, and material structure investigation. Now that we have completed the development of the 1MV-FE- TEM (H-1000FT), we report its performance from the viewpoint of coherent illumination.

We observed thin films of gold in testing the high-resolution performance of H-1000FT.Crystal lattice fringes are formed from the interference between Bragg diffracted electron waves. In TEM observation of the films, the visibility of the fringes depends on the coherence of the electron wave and the overall stability of the microscope. Here, we calculated chromatic aberration-limited resolution d, given by ∼-(Δ ƛ)1/2, to be ∼ 0.6 Å (Δ:focus spread). We then slightly tilted the illumination to partially escape from the chromatic effect and to enable us to a shorter spacing lattice image. Figure 1 shows a lattice fringe image we obtained for a Au thin film, in which lattice fringes of 0.498 Å are clearly visible.
A Low Cost Configuration for Internetwork Telemicroscopy
Authors: Dorward D W
Published: July 2020

Advances in internetwork data transmission rates and reductions in the cost of imaging components and applications have facilitated real-time sharing of video, still images, and microscope operating systems with collaborators or observers at remote locations. Specialized direct and web-based systems for transmission electron microscopy have been described previously. However, in order to develop a generic and flexible means of sharing live images and data from light, scanning electron, and transmission electron microscope instruments, a telemicroscopy system was configured using readily available components and software that can be adapted for use with most common computer operating and networking systems.

Figure 1 diagrams the general configuration used in our laboratory. Input devices can include inexpensive desktop digital or analog video cameras, specialized fast or slow scan CCD cameras, and the analog video-screen signal generated by scanning electron microscopes. For transmission through TCP/IP networks, analog signals must be digitized with a frame grabber card.
A Novel Method for Automated Acquisition of Tilt Series for Electron Tomography Based on Pre-Calibration of the Specimen Stage
Authors: Ziese U , Janssen AH , Krift TP van der , Balen AG van , Ruijter WJ de , Roster AJ
Published: July 2020

Electron tomography is a three-dimensional (3D) imaging method with transmission electron microscopy (TEM) that provides high-resolution 3D images of structural arrangements. Conventional TEM images are in first approximation mere 2D-projections of a 3D sample under investigation. With electron tomographya series of images is acquired of a sample that is tilted over a large angular range (±70°) with small angular tilt increments (so called tilt-series). For the subsequent 3D-reconstruction, the images of the tilt series are aligned relative to each other and the 3D-reconstruction is computed. Electron tomography is the only technique that can provide true 3D information with nm-scale resolution of individual and unique samples. For (cell) biology and material science applications the availability of high-resolution 3D images of structural arrangements within individual samples provides unique architectural information that cannot be obtained otherwise. Routine application of electron tomography will comprise a major revolutionary step forward in the characterization of complex materials and cellular arrangements.
Tele-Tutoring - From Learning to Earning Part II: The use of Remote Technologies
Authors: Bailey GW , McKernan S , Price RL , Walck SD , Charest P-M , Gauvin R , Lang J , Stuan C , Casuccio G , Kennedy S , Kritikos D , Lentz H
Published: July 2020

The West Greene School District (WGSD) in partnership with RJ Lee Group (RJLG) has been designing and developing innovative programs as part of the Schoolhouse Project to provide exceptional educational and business opportunities to its students. The objective of the educational/business partnership are multiple including motivating students to pursue advanced education, especially in mathematics, computer sciences, engineering, and the basic sciences; enriching the educational experience beyond that commonly available to students in rural communities; and improving the general attractiveness of the region for business growth. Access to remote analytical instrumentation is a key component of the Schoolhouse Project. To encourage remote access, RJLG has recently developed microscopy-at-a-distance Web-based technologies which enable control and operation of a scanning electron microscope (SEM) over the internet.

The SEM was chosen as the initial advanced analytical instrumentation because 1) its imaging and elemental composition functions have made it a standard analytical tool throughout research and industry, 2) it can be applied to many disciplines, and 3) students find it easy and fun to operate.
VSEM : An Interactive Simulation and Virtual Reality Model of the Scanning Electron Microscope
Authors: Bailey GW , McKernan S , Price RL , Walck SD , Charest P-M , Gauvin R , Holburn DM , Breton BC , Robertson RP , Thompson JS , Caldwell NHM
Published: July 2020

The capabilities of the scanning electron microscope (SEM continue to grow. An understanding of and competency in operating the SEM is a vital asset to researchers in many fields. Acquiring the practical knowledge demands considerable training, which is expensive in terms of instrument time and personnel resources. Moreover confined laboratory environments severely limit the number of operators who can be trained simultaneously.

An alternative training approach is to develop software simulations. For example, the Interactive Microscope Laboratory simulates the optical microscope as part of a computer-based teaching resource for school-level biology courses. The VSEM (Virtual Scanning Electron Microscope) project extends our earlier work on emulating the operation and behaviour of the SEM and combines it with a virtual reality model of the instrument. The aim of the VSEM project has been to develop a microscopy teaching application which can be deployed on multiple platforms without the need for expensive hardware or software support facilities.
The Tech Trek - Mobile Research Laboratory Enhances Educational Outreach Efforts at Wright-Patterson Air Force Base, Ohio.
Authors: Piazza Luann , Ragland William R , Thorp Katie E G , Martin Marc C
Published: July 2020

Wright-Patterson Air Force Base (near Dayton, OH) continues to expand their local community educational outreach programs with the new mobile science research laboratory, Tech Trek - Mobile Research Laboratory. Tech Trek serves surrounding communities using a 40-foot customized Blue Bird bus equipped with an R.J. Lee Instruments Limited portable scanning electron microscope (SEM). The microscope is on loan from the Materials and Manufacturing Directorate of the Air Force Research Laboratory (AFRL) at Wright-Patterson Air Force Base.

The purpose of the Tech Trek program is to stimulate school science programs by making state-of-the-art, usually cost-prohibitive scientific equipment and experienced support staff accessible to schools. The program is focussed on providing opportunities for students currently in the grades six through twelve, our future scientists and engineers, to interact with role models in science and technology while being engaged in interesting scientific research. Using this mobile format combination classroom and laboratory,
Teaching Microscopy and Microscope Theory Based on Remote Instrument Access and Instrument Automation
Authors: Bailey GW , McKernan S , Price RL , Walck SD , Charest P-M , Gauvin R , Voelkl E , Allard LF , Tarnoff D , Williams DB , Fama LA
Published: July 2020

The intense use of computers to operate electron microscopes as well as the ability to control microscopes remotely over the Internet, is increasingly changing the way electron microscopes are being used and how microscopy is being taught. Practically all of the top-of-the-line electron microscopes offered by the microscope vendors today are fully computer controllable, and provide for digital imaging. The combination of both features with the ever increasing speed of computers has created a situation that has and will continue to change the way electron microscopists work.

Lehigh University together with Oak Ridge National Laboratory have collaborated since 1996 to make the instrumentation in the High Temperature Materials Laboratory at ORNL available for teaching purposes. The primary instrument being used is the Hitachi HF-2000 field emission TEM, which is controlled by Gatan's DigitalMicrograph™ (DM) software and uses a Ik by Ik CCD camera for digital imaging.
Telepresence Confocal Microscopy
Authors: J. H. Youngblom , J. Wilkinson , J.J. Youngblom
Published: July 2020

The advent of the Internet has allowed the development of remote access capabilities to a growing variety of microscopy systems. The Materials MicroCharacterization Collaboratory, for example, has developed an impressive facility that provides remote access to a number of highly sophisticated microscopy and microanalysis instruments. While certain types of microscopes, such as scanning electron microscopes, transmission electron microscopes, scanning probe microscopes, and others have already been established for telepresence microscopy, no one has yet reported on the development of similar capabilities for the confocal laser scanning microscope.

At California State University-Stanislaus, home of the CSUPERB (California State University Program for Education and Research in Biotechnology) Confocal Microscope Core Facility, we have established a remote access confocal laser scanning microscope facility that allows users with virtually any type of computer platform to connect to our system. Our Leica TCS NT confocal system, with an interchangeable upright (DMRXE) and inverted microscope (DMIRBE) set up,
Soaring with Scope-on-a-Rope at LSU: Development of Innovative Microscopy Technology for K-16 Classroom use
Authors: Henk M C , Silverman H
Published: July 2020

LSU began introducing a prototype SCOPE-ON-A-ROPE (SOAR) to selected teachers in Louisiana and Tennessee three years ago as part of our K-12 outreach activities. It proved to be an invaluable aid to all K-12 classrooms as well as to college classrooms or laboratories in several disciplines. The SOAR is extremely easy to use in the normal classroom setting, but can also introduce sophisticated concepts usually possible only through complicated microscopy exercises with specialized instrumentation.

The professional microscopist who occasionally teaches students how to use microscopes can only begin to appreciate the position of classroom teachers who are routinely faced with inadequate, insufficient microscopes for classes of 20- 30 students at a time. This SOAR, inspired by industrial inspection devices, aids the teacher in introducing valuable concepts in microscopy and scale while easily serving the functions of many different microscopes and accessories. It is a comfortably hand-held device that can be used capably even by a five-year-old to provide excellent,
Multi-Photon Excitation Microscopy: An Old Idea in Quantum Theory Applied to Modern Scientific Problems
Authors: Piston David W
Published: July 2020

Multi-photon excitation microscopy provides attractive advantages over confocal microscopy for three-dimensionalry resolved fluorescence imaging and photochemistry. The most commonly used type of multi-photon excitation is two-photon excitation where simultaneous absorption of two photons leads to a single quantitized event. The powerful advantages of using two-photon excitation microscopy arise from the basic physical principle that the absorption depends on the square of the excitation intensity. In practice, two-photon excitation is generated by focusing a single pulsed laser through the microscope. As the laser beam is focused, the photons become more crowded, but the only place at which they are crowded enough to generate an appreciable amount of two-photon excitation is at the focus. Above and below the focus, the photon density is not high enough for two of them to interact with a single fluorophore at the same time. This dramatic difference between confocal and two-photon excitation microscopy is shown in Fig. 1.
Structural Analysis of Proteins on Lipid Substrates
Authors: Wilson-Kubalek Elizabeth M
Published: July 2020

Electron microscopy (EM) has become an increasingly powerful method for the determination of three-dimensional (3D) structures of proteins and macromolecular complexes. EM offers advantages over X-ray crystallography and NMR for obtaining structural information about proteins in physiological conditions, as components of large assemblies, that cannot be obtained in large quantity, or that fail to yield 3D crystals. EM has been used to obtain structural data from images of isolated molecules and molecular complexes, two-dimensional (2D) protein crystals, and helical protein arrays. Helically arranged proteins allow the most rapid determination of 3D maps because they contain a complete range of equally spaced molecular views, therefore no tilting of the sample with respect to the electron beam is required. However, so far 3D structure determination of helical assemblies has been limited to proteins that naturally adopt this organization and to proteins that fortuitously crystallize as helices.
Tutorial: Single Particle Analysis of Macromolecules and Complexes: How to Get Started
Authors: Ludtke S
Published: July 2020

Single particle processing is a technique for determining the 3D structure of molecules and macromolecular assemblies using TEM images of individual molecules. In principle, individual molecules float freely in solution before freezing/fixation, so particles in the micrographs represent 2D projections of individual molecules in random, or nearly random orientations. Practically speaking, surface effects often cause preferred orientations to exist in the particle population. In addition, single particle processing makes the assumption that all of the individual molecules are either in the same conformation, or in a discrete mixture of conformations. Single particle processing refers to the computational techniques by which thousands of individual molecule images are processed to produce a 3D structure. The technology of single particle processing has advanced to the point that a low resolution reconstruction (∼ 15-25 Å) can be performed on a cooperative specimen quite rapidly, typically less than a month from purified specimen to 3D model.
Energy-Filtered Imaging: A Tutorial
Authors: Bentley J
Published: July 2020

Over the several years that imaging energy filters have been available commercially, numerous and wide-ranging applications have demonstrated elemental mapping with a resolution approaching 1 nm. A few reports have even shown resolutions <0.4 nm. Elemental mapping by energy-filtered transmission electron microscopy (EFTEM) is clearly an attractive and powerful tool, but some aspects of the techniques can be complex, with many pitfalls awaiting the unwary. This tutorial aims to cover some practical aspects of elemental mapping by EFTEM. It is based largely on the author's work at the ORNL SHaRE User Facility, where EFTEM research has been performed since 1994 with a Gatan imaging filter (GIF) interfaced to a Philips CM30T operated at 300 kV with a LaBa cathode.120 Most of the applications have been to metals and ceramics, emphasizing interfacial segregation and precipitation.

For quantitative composition mapping by EFTEM a number of interrelated parameters [field of view, resolution (δ),
The NCEM One-Angstrom Microscope Project Reaches 0.89Å Resolution
Authors: O'Keefe Michael A
Published: July 2020

Transmission electron microscopy to a resolution of 0.89Å has been achieved at the National Center for Electron Microscopy and is available to electron microscopists who have a requirement for this level of resolution. Development of this capability commenced in 1993, when the National Center for Electron Microscopy agreed to fund a proposal for a unique facility, a one- Ångstrom microscope (OÅM).2 The OÅM project provides materials scientists with transmission electron microscopy at a resolution better than one Angstrom by exploiting the significantly higher information limit of a FEG-TEM over its Scherzer resolution limit. To turn the misphased information beyond the Scherzer limit into useful resolution, the OÅM requires extensive image reconstruction. One method chosen was reconstruction from off-axis holograms; another was reconstruction from focal series of underfocused images. The OÅM is then properly a combination of a FEG-TEM (a CM300FEG-UT) together with computer software able to generate sub-Ångstrom images from experimental images obtained on the FEG-TEM.

Before the advent of the OÅM, NCEM microscopists relied on image simulation to obtain structural information beyond the TEM resolution limit.
Microstructure of Cr-B Ohmic and Rectifying Contacts on (0001) 6H Sic
Authors: Liu R-J , Porter L M , Kim M J , Carpenter R W , Davis R F
Published: July 2020

6H-SiC is a wide band-gap semiconductor. In recent years, a variety of high-power, -temperature, -speed and opto-electronic devices have been produced in 6H-SiC films. The future development of SiC device technology depends on the ability to form good ohmic and Schottky contacts. Plots of the current-voltage (I-V) characteristics of Cr-B contacts on (0001) 6H-SiC revealed that they became the most ohmic-like after annealing at 1000 °C for 240 sec. and rectifying after annealing for 300 sec, therefore TEM analysis of the microstructures of as-deposited and annealed Cr-B films should help in understanding what causes both the ohmic-like and rectifying behaviors.

In this research, CrxBy film was deposited on vicinal (0001) 6H-SiC substrates by electron beam evaporation at room temperature. The intended phase was CrB2. Fig.l shows the microstructure of the as-deposited specimen. 6H-SiC appears to be a perfect crystal, but the Cr-B film had columnar polycrystalline microstructure.
US–China Trade War: A Way Out?
Authors: Zhou Weihuan , Gao Henry
Published: July 2020

Recently, a group of eminent Chinese/US economists and legal scholars issued a thought-provoking Joint Statement on ‘US–China Trade Relations: A Way Forward’. However, the Joint Statement does not provide practical solutions to the real issues in the bilateral negotiations. Moreover, by granting excessive policy space to the two largest trading nations, it would encourage them to further deviate from WTO rules and undermine the multilateral trading system. Drawing on the Theory of Distortions and Welfare, we put forward an alternative framework for the parties to tackle protectionist and trade distortive policy instruments while leaving sufficient policy space for them to pursue non-protectionist policy goals. Our framework would minimize WTO-inconsistent outcomes and prevent further erosion of the multilateral system as we encourage the parties to negotiate in a WTO-consistent manner. Hopefully, this would also provide the groundwork for more inclusive trade negotiations under the multilateral trading system.
Medienbezogene Störungen im Kindes- und Jugendalter: Evidenzpapier der Gemeinsamen Suchtkommission der kinder- und jugendpsychiatrischen und psychotherapeutischen Fachgesellschaft und Verbände (DGKJP, BAG, BKJPP)
Authors: Paschke Kerstin , Holtmann Martin , Melchers Peter , Klein Marianne , Schimansky Gisela , Krömer Thomas , Reis Olaf , Wartberg Lutz , Thomasius Rainer
Published: July 2020

Zusammenfassung. Unter der Bezeichnung Medienbezogene Störungen (MBS) wird sowohl eine problematische Nutzung des Internets und bestimmter Endgeräte generell als auch ein problematischer Gebrauch bestimmter Anwendungen zusammengefasst. Im Kindes- und Jugendalter kommen hierbei den Anwendungen Computerspiele und Soziale Netzwerke die größte Bedeutung zu. Im Mai 2019 wurde die Computerspielstörung als erste Entität der MBS als klinische Diagnose in die ICD-11 aufgenommen. Die Prävalenz der MBS im Kindes- und Jugendalter liegt in Deutschland bei 3 bis 5 %. Bei der Mehrzahl der Betroffenen gehen MBS mit komorbiden psychischen Störungsbildern einher. MBS entstehen auf der Grundlage dysfunktionaler Lernprozesse unter Wechselwirkung allgemeiner und spezfischer Risikofaktoren und gehen mit neuronalen Veränderungen ähnlich derer bei substanzgebundenen Süchten einher. Im Rahmen der Diagnostik stehen neben der kinder- und jugendpsychiatrischen/-psychotherapeutischen Exploration Fragebögen zur Verfügung, wobei ein einheitliches klinisches Vorgehen bislang fehlt. Die Behandlung umfasst in Abhängigkeit des Schweregrades ambulante, tagesklinische oder stationäre Therapieangebote mit kognitiv-behavioralen Elementen unter Einbezug der Eltern. Diese sind bislang nicht flächendeckend vorhanden und unzureichend evaluiert. Zudem existieren bislang wenige Untersuchungen zur Wirksamkeit von Präventionsmaßnahmen bei MBS im Kindes- und Jugendalter. Eine Vertiefung der Forschung ist dringend geboten.
Space Weather Lessons from a 1928 Dirigible Debacle
Authors: Fritts Rachel
Published: July 2020

Analysis of a disrupted SOS signal during an early polar expedition showcases the importance of taking space weather into account when exploring new frontiers.
Modeling: A Powerful and Versatile Tool in Glaciology
Authors: Sergienko Olga , Morlighem Mathieu , Nowicki Sophie , Padman Laurence
Published: July 2020

Papers are invited for a new special collection presenting advances in modeling in glaciology that improve understanding of glaciers and ice sheets and their interactions with the Earth system.
New Evidence of a Giant Lava Lamp Beneath the Ancient Pacific
Authors: Evans Kate
Published: July 2020

Seismic surveys find evidence of a superplume in Earth’s mantle that fueled ancient megaeruptions in the Pacific.
Physiological dynamics of chemosynthetic symbionts in hydrothermal vent snails
Authors: Breusing Corinna , Mitchell Jessica , Delaney Jennifer , Sylva Sean P , Seewald Jeffrey S , Girguis Peter R , Beinart Roxanne A
Published: July 2020

Symbioses between invertebrate animals and chemosynthetic bacteria form the basis of hydrothermal vent ecosystems worldwide. In the Lau Basin, deep-sea vent snails of the genus Alviniconcha associate with either Gammaproteobacteria (A. kojimai, A. strummeri) or Campylobacteria (A. boucheti) that use sulfide and/or hydrogen as energy sources. While the A. boucheti host–symbiont combination (holobiont) dominates at vents with higher concentrations of sulfide and hydrogen, the A. kojimai and A. strummeri holobionts are more abundant at sites with lower concentrations of these reductants. We posit that adaptive differences in symbiont physiology and gene regulation might influence the observed niche partitioning between host taxa. To test this hypothesis, we used high-pressure respirometers to measure symbiont metabolic rates and examine changes in gene expression among holobionts exposed to in situ concentrations of hydrogen (H2: ~25 µM) or hydrogen sulfide (H2S: ~120 µM). The campylobacterial symbiont exhibited the lowest rate of H2S oxidation but the highest rate of H2 oxidation, with fewer transcriptional changes and less carbon fixation relative to the gammaproteobacterial symbionts under each experimental condition. These data reveal potential physiological adaptations among symbiont types, which may account for the observed net differences in metabolic activity and contribute to the observed niche segregation among holobionts.
Angiosarcoma of bone: a retrospective study of the European Musculoskeletal Oncology Society (EMSOS)
Authors: Palmerini Emanuela , Leithner Andreas , Windhager Reinhard , Gosheger Georg , Boye Kjetil , Laitinen Minna , Hardes Jendrik , Traub Frank , Jutte Paul , Willegger Madeleine , Casanova Jose’ , Setola Elisabetta , Righi Alberto , Picci Piero , Donati Davide Maria , Ferrari Stefano
Published: July 2020

Angiosarcoma of bone (B-AS) is a rare malignant tumor of vascular origin. The aim of this retrospective study is to report on treatments and prognosis. Data were collected from the EMSOS website. 80 patients in 9 centers included: 51 male/29 female; median age 54 years (range 17 to 92); 56% with localized disease, 44% metastatic. Primary tumor surgery: 76% (30% amputation, 26% intralesional margins); radiotherapy (RT): 41%; chemotherapy (CT): 47% (56% in metastatic, 41% in localized cases). With a median follow-up of 31 months (range 40 to 309), 5-year overall survival (OS) was 27% (95%CI 16–30): 41% (95%CI 25–56) for localized patients, and 8% (95%CI 0–20) for metastatic (p = 0.002). In metastatic patients, 1 year OS was significantly influenced by chemotherapy response: 67% (95CI% 29–100) for those who responded or had stable disease (n = 7), and 18% (95CI% 0–41) for patients with progressive disease (n = 11), p 0.002. The surgical complete remission (SCR) status was pivotal in localized patients (5-year OS 45% for SCR, 17% no SCR, p = 0.03); also 5-year OS was significantly influenced by age and site of the tumor. After multivariate analysis, the addition of radiotherapy to surgery significantly influenced the disease-free survival (DFS) rate, whereas the use of chemotherapy lost the significance showed at the univariate analysis. Overall, patients with metastatic B-AS have a dismal prognosis, with a prolonged survival in case with a response to chemotherapy. Experimental trials with more active systemic treatment regimens are needed. In patients with localized disease, the patient’s age and site of the tumor are prognostic factors and any effort must be made to achieve an SCR status. No definitive conclusions can be drawn from our data on the use of adjuvant chemotherapy, while the use of adjuvant radiotherapy might improve DSF in patients surgically free of disease.
Heterologous activation of the Hevea PEP16 promoter in the rubber-producing laticiferous tissues of Taraxacum kok-saghyz
Authors: Ganesh Irisappan , Choi Sang Chul , Bae Sung Woo , Park Jong-Chan , Ryu Stephen Beungtae
Published: July 2020

Hevea brasiliensis, the most abundant rubber crop, is used widely for the commercial production of natural rubber. To reduce the risk of a shortage in the supply of natural rubber that may arise from a single major rubber crop, rubber dandelion (Taraxacum kok-saghyz) has been developed as an alternative rubber-producing crop by using a transgenic approach. However, it is necessary to identify a suitable promoter for the transfer of rubber biosynthesis-related genes to the species. In this study, the promoter region of H. brasiliensis PEP16, which was isolated as a potentially important component in rubber biosynthesis, was sequenced and a pPEP16::GUS fusion construct was introduced into T. kok-saghyz. Histological and fluorometric studies using transgenic T. kok-saghyz plants indicated that the HbPEP16 promoter was highly activated in a laticiferous tissue-specific manner under normal growth conditions and that promoter activation was tightly regulated by various hormones and external signals. These findings suggested that the HbPEP16 promoter may be a useful molecular tool for the manipulation of gene expression in the laticiferous tissues of T. kok-saghyz.
Polycyclic aromatic hydrocarbons: bioaccumulation in dragonfly nymphs (Anisoptera), and determination of alkylated forms in sediment for an improved environmental assessment
Authors: Girardin Viviane , Grung Merete , Meland Sondre
Published: July 2020

Road runoff carries a mixture of contaminants that threatens the quality of natural water bodies and the health of aquatic organisms. The use of sedimentation ponds is a nature-based solution for the treatment of road runoff. This study assessed the concentration of polycyclic aromatic hydrocarbons (PAHs) and their alkylated homologues in sediment from seven highway sedimentation ponds and three natural urban ponds. In addition, the study explored the bioaccumulation of PAHs in dragonfly nymphs (Anisoptera). Finally, biota-sediment accumulation factors (BSAFs) were estimated. The results revealed a significant difference in the concentrations of 16 priority PAHs in sediment, with overall higher levels in sedimentation ponds (2,911 µg/kg on average) compared to natural urban ponds (606 µg/kg on average). PAH levels increased substantially once alkylated homologues were considered, with alkylated comprising between 42 and 87% of the total PAH in sediment samples. These results demonstrate the importance of alkylated forms in the environmental assessment of PAHs. The bioaccumulation assessment indicates that dragonfly nymphs bioaccumulate PAHs to a certain degree. It is not clear, however, whether they metabolize PAHs. BSAF results ranged from approx. 0.006 to 10 and indicate that BSAFs can be a powerful tool to determine the functionality of sedimentation ponds.
Unconstrained multivariate EEG decoding can help detect lexical-semantic processing in individual children
Authors: Petit Selene , Badcock Nicholas A. , Grootswagers Tijl , Woolgar Alexandra
Published: July 2020

In conditions such as minimally-verbal autism, standard assessments of language comprehension are often unreliable. Given the known heterogeneity within the autistic population, it is crucial to design tests of semantic comprehension that are sensitive in individuals. Recent efforts to develop neural signals of language comprehension have focused on the N400, a robust marker of lexical-semantic violation at the group level. However, homogeneity of response in individual neurotypical children has not been established. Here, we presented 20 neurotypical children with congruent and incongruent visual animations and spoken sentences while measuring their neural response using electroencephalography (EEG). Despite robust group-level responses, we found high inter-individual variability in response to lexico-semantic anomalies. To overcome this, we analysed our data using temporally and spatially unconstrained multivariate pattern analyses (MVPA), supplemented by descriptive analyses to examine the timecourse, topography, and strength of the effect. Our results show that neurotypical children exhibit heterogenous responses to lexical-semantic violation, implying that any application to heterogenous disorders such as autism spectrum disorder will require individual-subject analyses that are robust to variation in topology and timecourse of neural responses.
Subcritical water extraction of bioactive compounds from Orostachys japonicus A. Berger (Crassulaceae)
Authors: Ko Min-Jung , Nam Hwa-Hyun , Chung Myong-Soo
Published: July 2020

Subcritical-water extraction is an ecofriendly method for extracting antioxidant compounds only using water. The Subcritical-water extraction was employed for the extraction of bioactive compounds from Orostachys japonicus known as rock pine by investigating the use of various temperatures (110–260 °C) and extraction times (5–20 min). The Subcritical-water extraction condition at 220 °C for 15 min; the total phenolics content (39.9 ± 4.1 mg/g), flavonoids content (11.4 ± 0.6 mg/g), and antioxidant activities (90.3 ± 2.2%, 96.0 ± 2.9%, and 662.4 ± 17.2 mg/g) of Subcritical-water extract were higher under this condition than for extraction with either methanol or ethanol. Triterpene saponins were observed only in subcritical-water extraction condition at 220 °C for 15 min. Further, some of its phenolic constituents; gallic acid, quercetin, and kaempferol were quantified by high performance liquid chromatography. Subcritical-water extraction is an effective method for extracting valuable bioactive compounds from Orostachys japonicus.
Variability and sex-dependence of hypothermic neuroprotection in a rat model of neonatal hypoxic–ischaemic brain injury: a single laboratory meta-analysis
Authors: Wood Thomas R. , Gundersen Julia K. , Falck Mari , Maes Elke , Osredkar Damjan , Løberg Else Marit , Sabir Hemmen , Walløe Lars , Thoresen Marianne
Published: July 2020

Therapeutic hypothermia (HT) is standard care for term infants with hypoxic–ischaemic (HI) encephalopathy. However, the efficacy of HT in preclinical models, such as the Vannucci model of unilateral HI in the newborn rat, is often greater than that reported from clinical trials. Here, we report a meta-analysis of data from every experiment in a single laboratory, including pilot data, examining the effect of HT in the Vannucci model.
Across 21 experiments using 106 litters, median (95% CI) hemispheric area loss was 50.1% (46.0–51.9%; n = 305) in the normothermia group, and 41.3% (35.1–44.9%; n = 317) in the HT group, with a bimodal injury distribution. Median neuroprotection by HT was 17.6% (6.8–28.3%), including in severe injury, but was highly-variable across experiments. Neuroprotection was significant in females (p < 0.001), with a non-significant benefit in males (p = 0.07). Animals representing the median injury in each group within each litter (n = 277, 44.5%) were also analysed using formal neuropathology, which showed neuroprotection by HT throughout the brain, particularly in females. Our results suggest an inherent variability and sex-dependence of the neuroprotective response to HT, with the majority of studies in the Vannucci model vastly underpowered to detect true treatment effects due to the distribution of injury.
Effects of repetitive Iodine thyroid blocking on the foetal brain and thyroid in rats: a systems biology approach
Authors: Cohen David P. A. , Benadjaoud Mohamed Amine , Lestaevel Phillipe , Lebsir Dalila , Benderitter Marc , Souidi Maâmar
Published: July 2020

A single administration of an iodine thyroid blocking agent is usually sufficient to protect thyroid from radioactive iodine and prevent thyroid cancer. Repeated administration of stable iodine (rKI) may be necessary during prolonged or repeated exposure to radioactive iodine. We previously showed that rKI for eight days offers protection without toxic effects in adult rats. However, the effect of rKI administration in the developing foetus is unknown, especially on brain development, although a correlation between impaired maternal thyroid status and a decrease in intelligence quotient of the progeny has been observed. This study revealed distinct gene expression profiles between the progeny of rats receiving either rKI or saline during pregnancy. To understand the implication of these differentially expressed (DE) genes, a systems biology approach was used to construct networks for each organ using three different techniques: Bayesian statistics, sPLS-DA and manual construction of a Process Descriptive (PD) network. The PD network showed DE genes from both organs participating in the same cellular processes that affect mitophagy and neuronal outgrowth. This work may help to evaluate the doctrine for using rKI in case of repetitive or prolonged exposure to radioactive particles upon nuclear accidents.
Two latent classes of diagnostic and treatment procedures among traumatic brain injury inpatients
Authors: Beydoun Hind A. , Butt Catherine , Beydoun May A. , Eid Shaker M. , Zonderman Alan B. , Johnstone Brick
Published: July 2020

To characterize latent classes of diagnostic and/or treatment procedures among hospitalized U.S. adults, 18–64 years, with primary diagnosis of TBI from 2004–2014 Nationwide Inpatient Samples, latent class analysis (LCA) was applied to 10 procedure groups and differences between latent classes on injury, patient, hospital and healthcare utilization outcome characteristics were modeled using multivariable regression. Using 266,586 eligible records, LCA resulted in two classes of hospitalizations, namely, class I (n = 217,988) (mostly non-surgical) and class II (n = 48,598) (mostly surgical). Whereas orthopedic procedures were equally likely among latent classes, skin-related, physical medicine and rehabilitation procedures as well as behavioral health procedures were more likely among class I, and other types of procedures were more likely among class II. Class II patients were more likely to have moderate-to-severe TBI, to be admitted on weekends, to urban, medium-to-large hospitals in Midwestern, Southern or Western regions, and less likely to be > 30 years, female or non-White. Class II patients were also less likely to be discharged home and necessitated longer hospital stays and greater hospitalization charges. Surgery appears to distinguish two classes of hospitalized patients with TBI with divergent healthcare needs, informing the planning of healthcare services in this target population.
Non-contact imaging of peripheral hemodynamics during cognitive and psychological stressors
Authors: McDuff Daniel , Nishidate Izumi , Nakano Kazuya , Haneishi Hideaki , Aoki Yuta , Tanabe Chihiro , Niizeki Kyuichi , Aizu Yoshihisa
Published: July 2020

Peripheral hemodynamics, measured via the blood volume pulse and vasomotion, provide a valuable way of monitoring physiological state. Camera imaging-based systems can be used to measure these peripheral signals without contact with the body, at distances of multiple meters. While researchers have paid attention to non-contact imaging photoplethysmography, the study of peripheral hemodynamics and the effect of autonomic nervous system activity on these signals has received less attention. Using a method, based on a tissue-like model of the skin, we extract melanin$$\text {C}_{m}$$Cmand hemoglobin$$\text {C}_{HbO}$$CHbOconcentrations from videos of the hand and face and show that significant decreases in peripheral pulse signal power (by 36% ± 29%) and vasomotion signal power (by 50% ± 26%) occur during periods of cognitive and psychological stress. Via three experiments we show that similar results are achieved across different stimuli and regions of skin (face and hand). While changes in peripheral pulse and vasomotion power were significant the changes in pulse rate variability were less consistent across subjects and tasks.
Biological properties of almond proteins produced by aqueous and enzyme-assisted aqueous extraction processes from almond cake
Authors: de Souza Thaiza S. P. , Dias Fernanda F. G. , Oliveira Joana Paula S. , de Moura Bell Juliana M. L. N. , Koblitz Maria Gabriela B.
Published: July 2020

The almond cake is a protein-rich residue generated by the mechanical expression of the almond oil. The effects of the aqueous (AEP) and enzyme-assisted aqueous extraction processes (EAEP) on the biological properties of the almond cake protein were evaluated. Total phenolic content (TPC), antioxidant capacity, inhibitory effects against crucial enzymes related to metabolic syndrome, antimicrobial potential, and in vitro protein digestibility profile were assessed. EAEP provided the best results for antioxidant capacity by both ORAC (397.2 µmol TE per g) and ABTS (650.5 µmol TE per g) methods and also showed a high (~ 98%) potential for α-glucosidase inhibition. The AEP resulted in protein extracts with the highest lipase inhibition (~ 70%) in a dose-dependent way. Enzymatic kinetic analyses revealed that EAEP generated uncompetitive inhibitors against α-glucosidase, while EAEP, AEP, and HEX-AEP (used as control) generated the same kind of inhibitors against lipase. No protein extract was effective against any of the bacteria strains tested at antimicrobial assays. An in silico theoretical hydrolysis of amandin subunits corroborated with the results found for antioxidant capacity, enzyme inhibitory experiments, and antimicrobial activity. Digestibility results indicated that the digestive proteases used were efficient in hydrolyzing almond proteins, regardless of the extraction applied and that HEX-AEP presented the highest digestibility (85%). In summary, EAEP and AEP skim proteins have the potential to be used as a nutraceutical ingredient. The biological properties observed in these extracts could help mitigate the development of metabolic syndrome where EAEP and AEP skim proteins could be potentially used as a prophylactic therapy for diabetes and obesity, respectively.