bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theoretical and Experimental Approaches to Identification of a Fiber Surface Cell Binding Domain in Collagen and its Application in Tissue Engineering.
Authors: Bhatnagar Rajendra S , Shattuck Mark B , Qian Jing Jing , Gough Craig A , Nicoll Steven B 
Published: July 2020

Abstract
Type I collagen comprises between 75-95% of the stationary extracellular matrix of most tissues, forming a continuum in which most of the static cells are anchored. Collagen serves as the track for haptotactic cell migration. The junction between collagen, its receptor integrins, and the cells’ cytoskeleton plays a crucial role in cell differentiation and morphogenesis by serving as the agent for transducing mechanical forces into chemical and biochemical work. The physiological, functional organization of collagen is the solid state in the form of a network of fibers. The only molecules available for engaging the receptors are those located on the fiber surface. Cryogenic scanning force microscopy (SFM) of single molecules of collagen allowed us to correlate surface features with known sequence and stereochemical markers within collagen. Theoretical conformational studies to locate markers for intermolecular recognition and allosteric binding showed that collagen a 1(1) chain residues 766GTPGPQGIAGQRGVV780 generate a distinctive conformation, characterized by a relatively stable (3-bend at the core (Fig. 1) within the triple helical polyproline II conformation extant in the rest of the molecule (1).
Detection of Early Cancers by Quantitative Cytology
Authors: Palcic B , Garner D , Sun XR 
Published: July 2020

Abstract
It has long been recognized that detecting cancers in their early, non-invasive stage is the best strategy to control malignant diseases. This has been best demonstrated by the example of cancer of the uterine cervix. Before screening for early signs of this malignancy, the prevalence of invasive cancer of the uterine cervix in the developed world was as high as 30 women per 100,000 and the mortality was 12-15 per 100,000 women per year, (all figures represent age standardized data). Since the introduction of cervical screening programs by Pap smears, the incidence of invasive cervical cancer and mortality due to this cancer has fallen dramatically. In British Columbia, for example, where population screening was introduced 50 years ago, the incidence and mortality have decreased several-fold and are at present below 6 and 3 per 100,000, respectively (1,2). It is believed that these figures could be even lower by encouraging more women into the program and by improving both sensitivity and specificity of the cytology.
7-Parameter Automated Measurement of the Shapes of Nanoscale Inclusion by TEM
Authors: Gabrisch H , Cong G , Parvin B , Kjeldgaard L , Johnson E , Dahmen U 
Published: July 2020

Abstract
The equilibrium shape of liquid inclusions in a crystalline matrix is a direct measure of the orientation dependence, or anisotropy, of the liquid/solid interfacial energy. In this work we have used diffraction contrast imaging in TEM to observe the shape of nanoscale liquid Pb inclusions in a solid Al matrix as a function of temperature. While a previous investigation reported a highly anisotropy equilibrium shape [1], more recent work showed that the inclusion shape depends on size, temperature and thermal history [2-4]. Here we report on a new method to make accurate automated measurements of these particle shapes during in-situ heating above the melting point of the inclusions.
Fig.l shows a typical bright field image of an array of liquid Pb inclusions in a solid Al matrix recorded at temperature during in-situ heating to 423°C. Under these two-beam diffraction conditions, particles are visible by absorption contrast and appear dark on a light background.
HRTEM Image Simulations of Structural Defects in Gate Oxides
Authors: Taylor S , Mardinly J , O'Keefe MA , Gronsky R 
Published: July 2020

Abstract
High-resolution transmission electron microscopy (HRTEM) is used extensively in the semiconductor industry for device characterization, and has become one of the highly favored techniques for characterizing the latest generation of ultra-thin gate oxides in MOSFET devices. However, relatively little is understood (either quantitatively or experimentally) about the limitations of HRTEM in detecting structural defects in gate oxides that could affect device performance. To investigate model defects experimentally, it would be necessary to construct “perfect” gate oxides, introduce defects with size and morphology known perfectly a priori, successfully make thin specimens that capture the defects, and then perform imaging experiments in the HRTEM. Since that task is virtually impossible, we have performed HRTEM image simulations to assess the visibility of various structural defects in gate oxides. The gate oxide was modeled as an amorphous silicon oxide 16.3Å-thick, sandwiched between a gate and substrate. The substrate was (100) silicon viewed along the [110] direction.
Diffusion of Ion Implanted Elements in Silicon by TEM And SIMS
Authors: Vanfleet RR , Francois-Saint-Cyr H , Stevie F , Giannuzzi L , Irwin R , Kempshell B , Shofner T 
Published: July 2020

Abstract
With the need to introduce new materials and processes to the semiconductor fabrication process, there is a great need to understand the diffusion of a large number of elements in silicon. To this end, a systematic SIMS study was done for implanted elements with subsequent annealing. There is a surprising lack of earlier work on many of the elements of the periodic table and the work that was done did not involve the additional effects of ion implantation.
The recent SIMS results allow the diffusion of the many elements to be categorized into several groups. These effects range from elements that do not appear to move substantially upon annealing, rapid diffusion to the surface, and formation of various peaks in the concentration profile.
Based on the SIMS results, we have used TEM to study the microstructure and composition of subset of the implants. The figure below shows the SIMS and TEM results for a Chromium implant.
Imaging Ionic Aggregates in Zn-Neutralized Sulfonated Polystyrene Ionomers: Shape and Spatial Heterogeneity
Authors: Kirkmeyer Brian P , Weiss Robert A , Winey Karen I 
Published: July 2020

Abstract
Ionomers are ionically-associating copolymers whose distinctive rheological and mechanical properties arise from the formation of ionic aggregates. The ionic aggregates form when dipoles of minority anionic polymer backbone segments and cationic neutralizing species locally associate and dissociate among each other. Specific ionomer properties depend upon the base copolymer, the minority constituent and the neutralizing agent. One system that has been studied extensively is sulfonated polystyrene ionomer neutralized with Zn (Zn-SPS). The most common technique to date for studying ionomer morphology is small-angle x-ray scattering (SAXS). This technique has provided quantitative information about the aggregate morphology by imposing morphology models that have not been independently confirmed.
In the present study, we demonstrate the capability to directly image the ionic aggregates of Zn-SPS ionomers using scanning transmission electron microscopy (STEM). This method will allow us to confirm or deny the competing morphological models applied to SAXS data. We have applied similar methods to polyethylene-based ionomers.
Development of a 1-MV Field-Emission Electron Microscope III. Electron Optical Design and Development of Field-Emission Electron Gun
Authors: Yoshida Takaho , Kawasaki Takeshi , Endo Junji , Furutsu Tadao , Matsui Isao , Matsuda Tsuyoshi , Osakabe Nobuyuki , Tonomura Akira , Kitazawa Koichi 
Published: July 2020

Abstract
Bright and coherent electron beams have been opening new frontiers in science and technology. So far, we have developed several field-emission transmission electron microscopes (FE-TEM) with increasing accelerating voltages to provide higher beam brightness. By using a 200-kV FE-TEM and electron holography techniques, we directly confirmed the Aharonov-Bohm effect. A 350-kV FE-TEM equipped with a low-temperature specimen stage enabled us to observe moving vortices in superconductors.2 Most Recently, we have developed a new 1-MV FE-TEM with a newly designed FE gun to obtain an even brighter and more coherent electron beam.
Electron beam brightness, Br, defined in Figure 1, is suitable for measuring the performance of electron guns, since both lens aberrations and mechanical/electrical vibrations contribute to a decrease in beam brightness, and beam coherency is proportional to (Br)1/2. Therefore, we optimized design of the illuminating system and its operation by maximizing the electron beam brightness.
Computer Controlled High-Throughput Integration System: FasTEM
Authors: Fukushima K , O'Donnell RM , Fujiwara K , Kai H , Okunishi E , Kawasaki M , Kersker M , Naruse M 
Published: July 2020

Abstract
Introduction
For the nano-area analysis of materials, it is necessary to evaluate all data obtained by HRTEM, EDS, EELS, and/or Energy Filter. Up till now, each analytical/imaging instrument required its original computer control system. Thus, the total operational environment for the nano-area analysis was not convenient for us. Recent progress of computer technology provides the ability to build a high performance environment for seamless operation by Client/Server design.
We have developed computer controlled high-throughput integration system based on PC, called FasTEM system, having seamless integration function and real-time remote control function of all instruments related to nano-area analysis. The FasTEM system is composed of Windows NT based Server PC System that is connected to the target TEM via RS232C for integrated operation, and Client PC SYSTEM connected to the Server PC via TCP/IP for remote operation (Fig.l).
Seamless Integration Function
All user interfaces of the analytical/imaging instruments, such as HRTEM, STEM BF/DF, EDS, PEELS and GIF can be seamlessly integrated into the Server PC.
Student Microscopes, A View from Down in the Trenches
Authors: Newberry S P 
Published: July 2020

Abstract
The use of microscopes in education has proved be a powerful tool in grades K through 12 for catching the student's interest in the sciences, the humanities and the arts. While the equipment and the approach varies with the grade level, the questions of availability, teacher training and cost are each important to obtaining full and successful use of microscopes in the classroom. The one item which is beyond the control of the school is the high cost of appropriate quality microscopes. A projection system capable of showing bacteria should be available to the teacher at all times and a number of microscopes which the students can use themselves should also be present Because of the cost, many schools, both public and private, have only one microscope room or share one set of microscopes for the entire school. The result is a study of the tool rather than using the tool to better appreciate history, ecology, high technology, medicine, and so forth.
Atom Probe Tomography: A Tutorial
Authors: Miller M K 
Published: July 2020

Abstract
Atom probe tomography (APT) is an ultrahigh resolution microanalytical technique that enables the spatial coordinates and elemental identities of the atoms in a small volume of material to be determined. The specimen volume that may be analyzed is typically ∼ 10 to 20 nm square by ∼ 100 to 250 nm deep, and contains up to ∼ 1 million atoms. The distribution of the solute atoms within this volume may then be reconstructed from these data. The compositions of small volumes are determined by simply counting the number of atoms of each type within that volume, and thus the technique provides a fundamental measure of local concentrations. Atom probe tomography requires that the specimen has some electrical conductivity and may be applied to almost all metals and alloys, many semiconductors, and some electrically conducting ceramics. The sharp needle-shaped specimens may be fabricated from bulk and thin film materials with the use of electropolishing, chemical or ion milling methods.
Changes in the balance between formal and informal care supply in England between 2001 and 2011: evidence from census data
Authors: Zigante Valentina , Fernandez Jose-Luis , Mazzotta Fernanda 
Published: July 2020

AbstractInformal care plays a crucial role in the social care system in England and is increasingly recognised as a cornerstone of future sustainability of the long-term care (LTC) system. This paper explores the variation in informal care provision over time, and in particular, whether the considerable reduction in publicly-funded formal LTC after 2008 had an impact on the provision of informal care. We used small area data from the 2001 and 2011 English censuses to measure the prevalence and intensity (i.e. the number of hours of informal care provided) of informal care in the population. We controlled for changes in age structure, health, deprivation, income, employment and education. The effects of the change in formal social care provision on informal care were analysed through instrumental variable models to account for the well-known endogeneity. We found that informal care provision had increased over the period, particularly among high-intensity carers (20+ hours per week). We also found that the reduction in publicly-funded formal care provision was associated with significant increases in high-intensity (20+ hours per week) informal care provision, suggesting a substitutive relationship between formal and informal care of that intensity in the English system.
A BRIDGE BETWEEN Q-WORLDS
Authors: DÖRING ANDREAS , EVA BENJAMIN , OZAWA MASANAO 
Published: July 2020

AbstractQuantum set theory (QST) and topos quantum theory (TQT) are two long running projects in the mathematical foundations of quantum mechanics (QM) that share a great deal of conceptual and technical affinity. Most pertinently, both approaches attempt to resolve some of the conceptual difficulties surrounding QM by reformulating parts of the theory inside of nonclassical mathematical universes, albeit with very different internal logics. We call such mathematical universes, together with those mathematical and logical structures within them that are pertinent to the physical interpretation, ‘Q-worlds’. Here, we provide a unifying framework that allows us to (i) better understand the relationship between different Q-worlds, and (ii) define a general method for transferring concepts and results between TQT and QST, thereby significantly increasing the expressive power of both approaches. Along the way, we develop a novel connection to paraconsistent logic and introduce a new class of structures that have significant implications for recent work on paraconsistent set theory.
DEPENDENT CHOICE, PROPERNESS, AND GENERIC ABSOLUTENESS
Authors: ASPERÓ DAVID , KARAGILA ASAF 
Published: July 2020

AbstractWe show that Dependent Choice is a sufficient choice principle for developing the basic theory of proper forcing, and for deriving generic absoluteness for the Chang model in the presence of large cardinals, even with respect to
$\mathsf {DC}$
-preserving symmetric submodels of forcing extensions. Hence,
$\mathsf {ZF}+\mathsf {DC}$
not only provides the right framework for developing classical analysis, but is also the right base theory over which to safeguard truth in analysis from the independence phenomenon in the presence of large cardinals. We also investigate some basic consequences of the Proper Forcing Axiom in
$\mathsf {ZF}$
, and formulate a natural question about the generic absoluteness of the Proper Forcing Axiom in
$\mathsf {ZF}+\mathsf {DC}$
and
$\mathsf {ZFC}$
. Our results confirm
$\mathsf {ZF} + \mathsf {DC}$
as a natural foundation for a significant portion of “classical mathematics” and provide support to the idea of this theory being also a natural foundation for a large part of set theory.
Increased Fractured Rock Permeability After Percolation Despite Limited Crack Growth
Authors: Renshaw Carl E. , Schulson Erland M. , Iliescu Daniel , Murdza Andrii 
Published: July 2020

AbstractFractured rock permeability can increase by crack extension that creates additional flow pathways or by increases in crack openings that increase crack transmissivity. Understanding the partitioning between these two mechanisms during rock deformation is critical for conceptual models of fluid flow and transport in crystalline rocks and sedimentary layers with low matrix permeability and for the hydromechanics of crustal rocks. Using ice as a model for rock, new systematic experiments reveal that when subject to uniaxial loading at a constant strain rate, crack density remains nearly constant after the onset of percolation even while permeability increases, indicating that after the onset of percolation the increase in permeability is primarily due to the opening of existing cracks rather than the extension of cracks. These observations have implications for conceptual models of fractured rock permeability that often focus on the evolution of permeability with changing fracture density rather than changing fracture transmissivity and for attempts to link fractured rock permeability to seismic properties that often dominantly consider changes in crack density rather than crack apertures.
Geomagnetic Storm‐Induced Plasma Density Enhancements in the Southern Polar Ionospheric Region: A Comparative Study Using St. Patrick's Day Storms of 2013 and 2015
Authors: Shreedevi P. R. , Choudhary R. K. , Thampi Smitha V. , Yadav Sneha , Pant T. K. , Yu Yiqun , McGranaghan Ryan , Thomas Evan G. , Bhardwaj Anil , Sinha A. K. 
Published: July 2020

AbstractThe occurrence of St. Patrick's Day (17 March) geomagnetic storms during two different years (2013 and 2015) with similar solar flux levels but varying storm intensity provided an opportunity to compare and contrast the responses of the ionosphere‐thermosphere (IT) system to different levels of geomagnetic activity. The evolution of positive ionospheric storms at the southern polar stations Bharati (76.6°S MLAT) and Davis (76.2°S MLAT) and its causative connection to the solar wind driving mechanisms during these storms has been investigated in this paper. During the main phase of both the storms, significant enhancements in TEC and phase scintillation were observed in the magnetic noon/ midnight period at Bharati and Davis. The TEC in the midnight sector on 17 March 2015 was significantly higher compared to that on 17 March 2013, in line with the storm intensity. The TEC enhancements during both the storm events are associated with the formation of the storm‐enhanced densities (SEDs)/tongue of ionization (TOI). The strong and sustained magnetopause erosion led to the prevalence of stronger storm time electric fields (prompt penetration electric field (PPEF)/subauroral polarization streams (SAPS)) for long duration on 17 March 2015. This combined with the action of neutral winds at midlatitudes favored the formation of higher plasma densities in the regions of SED formation on this day. The same was weaker during the 17 March 2013 storm due to the fast fluctuating nature of interplanetary magnetic field (IMF) Bz. This study shows that the duration and extent of magnetopause erosion play an important role in the spatiotemporal evolution of the plasma density distribution in the high‐midlatitude ionosphere.
Changes in Antarctic Bottom Water Formation During Interglacial Periods
Authors: Glasscock S. K. , Hayes C. T. , Redmond N. , Rohde E. 
Published: July 2020

AbstractIn the modern Southern Ocean and during the last interglacial period, Marine Isotope Stage 5e, there are observations that point to reduced Antarctic Bottom Water (AABW) formation. These reductions are believed to be driven by an increase in the strength of the Southern Ocean density stratification due to Antarctic ice melt‐induced surface water freshening. Any reduction in AABW formation has important implications for global climate as AABW plays a vital role in the cycling of carbon in the world's ocean. The primary question this study seeks to answer is do these AABW reductions occur during any of the other interglacials of the past 470,000 years? To study AABW changes in the paleoceanographic record, we look at changes in the redox record. Newly formed AABW is oxygen‐rich, so any reduction should lead to a decrease in oxygen concentrations in the deep Southern Ocean. The trace element uranium is useful for studying these redox changes as it is enriched in marine sediments under low‐oxygen conditions. When accounting for other factors, such as paleoproductivity, that can also decrease the oxygen concentrations in sedimentary porewater, it is possible to identify changes in AABW using authigenic uranium. The survey conducted by this study found a possible AABW reduction during late Marine Isotope Stage 11 (~397 ka). The cause of this event is less clear than others studied, and we explore the possibilities of ice melt‐induced freshening or a change in the position or strength of the Southern Hemisphere westerly winds.
Paleomagnetism of the Late Cretaceous Red Beds From the Far Western Lhasa Terrane: Inclination Discrepancy and Tectonic Implications
Authors: Bian Weiwei , Yang Tianshui , Jiang Zelei , Jin Jingjie , Gao Feng , Wang Suo , Peng Wenxiao , Zhang Shihong , Wu Huaichun , Li Haiyan , Cao Liwan , Deng Chenglong 
Published: July 2020

AbstractThe precollisional locations and geometries of the Lhasa terrane (LT) are critical to constrain the India‐Asia collision. However, the inclinations of the Cretaceous paleomagnetic data obtained from the northern limb of folds are obviously lower than those obtained from the southern limb, which cause large discrepant paleolatitudes of the LT prior to India‐Asia collision. Here, we carried out a new paleomagnetic investigation on the Late Cretaceous Jingzhushan Formation red beds in the far western LT. The tilt‐corrected site mean direction yielded a palaeopole at 74.4°N, 226.0°E with A95 = 3.8° (N = 54). This paleomagnetic data set passes fold tests and indicates that the studied area was located at 19.6° ± 3.8°N during the Late Cretaceous. However, the mean inclination calculated from the northern limb of folds (Is = 19.0°) is significantly lower than that of the southern limb of folds (Is = 51.8°). This inclination discrepancy of the Jingzhushan Formation red beds may be attributed to the syntectonic sedimentation. Nevertheless, the site mean direction obtained from both limbs of folds is generally consistent with the site mean direction after syntectonic‐sedimentation correction. Our new paleomagnetic results, combined with the reliable Cretaceous paleomagnetic results from the LT showed that the southern margin of Asia had a present‐day relatively east‐west alignment prior to India‐Asia collision.
Pathomechanisms in schwannoma development and progression
Authors: Helbing Dario-Lucas , Schulz Alexander , Morrison Helen 
Published: July 2020

AbstractSchwannomas are tumors of the peripheral nervous system, consisting of different cell types. These include tumorigenic Schwann cells, axons, macrophages, T cells, fibroblasts, blood vessels, and an extracellular matrix. All cell types involved constitute an intricate “tumor microenvironment” and play relevant roles in the development and progression of schwannomas. Although Nf2 tumor suppressor gene-deficient Schwann cells are the primary tumorigenic element and principle focus of current research efforts, evidence is accumulating regarding the contributory roles of other cell types in schwannoma pathology. In this review, we aim to provide an overview of intra- and intercellular mechanisms contributing to schwannoma formation.
“Genes load the gun, environment pulls the trigger.”
-George A. Bray