bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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 &lt;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

Abstract
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

Abstract
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

AbstractRecently, 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.
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

Abstract
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

AbstractAngiosarcoma 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

AbstractHevea 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.