20 research outputs found
Excavation Support for the Newseum Development at 555 Pennsylvania Avenue in Washington DC, USA
The Newseum consists of a 650,000 square-foot development that includes a six-level, 215,000 square-foot interactive museum of news. Also included is office space for the Newseum and Freedom Forum staff, a 9,000 square-foot conference center, more than 30,000 square feet of retail space and approximately 100 condominiums. The Newseum is located on Pennsylvania Avenue, between the U.S. Capital and the White House next to the Washington, D.C. mall and its museums and monuments. The building is supported on a mat foundation. The project is located just north of the Old Tiber Creek that was filled in the early 1800’s. Soft and compressible soils are present in the area that are prone to settlement from dewatering. These soils have also been associated with large movements of conventional H-pile and wood lagging excavation support systems and other problems in the past. Therefore, various “cut-off” walls were considered for excavation support that would not allow ground water levels around the building excavation to drop and would be less prone to soil erosion through wood lagging boards. Various cut-off walls were considered including a slurry wall, soil-mix wall, secant pile wall and Pile-in-Self-Hardening-Grout (PSHG) wall. A PSHG wall was selected for three sides of the excavation. The PSHG wall was constructed by inserting pre-fabricated panels consisting of steel H-piles and wood lagging into pre-excavated trenches using clamshell equipment normally used for slurry wall construction. A low strength self-hardening grout was used within the excavations to keep the sidewalls from caving, which hardened to strength of about 60 to 70 psi within a few days after installation of panels. The PSHG wall resulted in a relatively impermeable cutoff wall around three sides of the excavation. A secant pile wall was constructed at the east end of the excavation adjacent to the Canadian Embassy. The Canadian Embassy is founded on a mat foundation supported on relativity soft and compressible terrace age clay soils. A secant pile wall was selected adjacent to the Canadian Embassy to reduce the risk of settlement of the existing mat foundation. Ground water observation wells were monitored during construction to confirm that excessive ground water lowering below the Canadian Embassy mat did not occur. In addition, inclinometers and settlement points were monitored to measure movements of the Canadian Embassy, the secant pile wall, and PSHG wall. Both PSHG and secant pile walls were supported with tiebacks and both systems performed well within specified tolerances
Red Onion Mountain Maximum Security Prison − A Case Study in Ground Improvement
The Red Onion Mountain project involved the construction of a high security prison facility in a remote area of southwest Virginia. The site of the proposed construction was covered with a thick layer of uncontrolled mine spoil fill material containing a random matrix of soil and boulders. This material was unsuitable for the proposed construction in its existing condition. Charged with evaluating feasible and cost effective alternatives for site development and structural support, the project\u27s geotechnical engineers devised a two-phase ground improvement plan designed to adequately improve the existing mine spoil fill. Full-time observation, documentation and testing during the site preparation phase provided data that was used to evaluate the effectiveness of the ground improvement procedures. Building construction proceeded on the improved soils after an evaluation of the data indicated the existing mine spoil had been adequately improved
Тhe nature and characteristics of the evolution of the phenomenon of geopolitics
The article has revealed the nature of the phenomenon of geopolitics as being the basis of the international relations and serving both as a scientific methodology to explain the behavior and relationships of a state with other countries in accordance with the geographical location and the interests. The concept of modern geopolitics is multifaceted, and scientists disagree regarding the definition of geopolitics as an independent science. Geopolitics is a methodology of international relations and foreign policy. Ultimately, the key to modern understanding of geopolitics is the policy and the image of a state within its geographical location, which can impact other subjects / objects of international life to ensure their national interests and national security. A number of conceptual approaches have been formed in the scientific discourse aiming to ensure the geopolitical advantage of a state. New processes and conflicts have been associated with the expansion of the Internet space and information technology. Recently, geopolitical theories have taken into account the latest tools and capabilities to influence used by leading states, including use of information, "hybrid" and "semantic" warfares. One of most urgent problems of the modern world is information warfare targeting creation of favorable conditions to gain geopolitical and geo-economic priority
RomUkrSeis : seismic model of the crust and upper mantle across the Eastern Carpathians – from the Apuseni Mountains to the Ukrainian Shield
RomUkrSeis was carried out by a consortium of organisations, the Faculty of Geology and Geophysics and the Doctoral School of Geology of the University of Bucharest (Romania), the Subbotin Institute of Geophysics of the National Academy of Sciences of Ukraine (Kiev), the Institute of Geophysics of the Polish Academy of Sciences (Warsaw), the Deutsches GeoForschungsZentrum (Potsdam) and the School of Geosciences of the University of Aberdeen (Scotland). Financial support for drilling/shooting works on the territory of Romania came from S.C. Prospectiuni S.A. (with a special mention to former CEO Gehrig Stannard Schultz, currently at EPI Group, United Kingdom), Hunt Oil of Romania, Repsol Romania and on the territory of Ukraine from Ukrgeofizika. Participation of the Polish group in this work was supported within statutory activities No 3841/E-41/S/2014-2020 of the Ministry of Science and Higher Education of Poland. The authors express their sincere appreciation of the activities of many people who took part in field work and data acquisition. A large part of the instrumentation was provided by the Geophysical Instrument Pool of the Deutsches GeoForschungsZentrum (GFZ), Potsdam, Germany. Christian Haberland is thanked for his support and kindness facilitating the loan of this equipment to the RomUkrSeis consortium. The public domain packages GMT (Wessel and Smith, 1995) and Seismic Unix (Cohen and Stockwell Jr., 1997) were used in the preparation of maps and for seismic data processing. Tesseral Technologies Inc. (Calgary) developed the software for the full waveform modelling and we express our gratitude to their staff for technical support. The authors also wish to thank Professor Richard England (University of Leicester) and an anonymous reviewer for their constructive comments on an earlier version of this manuscript. This version is much improved as a result.Peer reviewedPostprin
Velocity model of the crust and upper mantle at the southern margin of the East European Craton (Azov Sea-Crimea-Black Sea area), DOBRE-2 & DOBRE'99 transect
The Wolbachia Genome of Brugia malayi: Endosymbiont Evolution within a Human Pathogenic Nematode
Complete genome DNA sequence and analysis is presented for Wolbachia, the obligate alpha-proteobacterial endosymbiont required for fertility and survival of the human filarial parasitic nematode Brugia malayi. Although, quantitatively, the genome is even more degraded than those of closely related Rickettsia species, Wolbachia has retained more intact metabolic pathways. The ability to provide riboflavin, flavin adenine dinucleotide, heme, and nucleotides is likely to be Wolbachia's principal contribution to the mutualistic relationship, whereas the host nematode likely supplies amino acids required for Wolbachia growth. Genome comparison of the Wolbachia endosymbiont of B. malayi (wBm) with the Wolbachia endosymbiont of Drosophila melanogaster (wMel) shows that they share similar metabolic trends, although their genomes show a high degree of genome shuffling. In contrast to wMel, wBm contains no prophage and has a reduced level of repeated DNA. Both Wolbachia have lost a considerable number of membrane biogenesis genes that apparently make them unable to synthesize lipid A, the usual component of proteobacterial membranes. However, differences in their peptidoglycan structures may reflect the mutualistic lifestyle of wBm in contrast to the parasitic lifestyle of wMel. The smaller genome size of wBm, relative to wMel, may reflect the loss of genes required for infecting host cells and avoiding host defense systems. Analysis of this first sequenced endosymbiont genome from a filarial nematode provides insight into endosymbiont evolution and additionally provides new potential targets for elimination of cutaneous and lymphatic human filarial disease
Resource-saving technologies for the production of elastic leather materials
This monograph contains a collection of recent research papers focusing on advancing existing technologies and developing new technologies to improve the environmentally friendliness and save resources during the production of elastic leather materials. The papers are organized based on the type of technological process used to preserve raw hides. A lot of attention is devoted to mathematical planning, simulations, and multicriteria optimization of the technological processes using newly developed chemical reagents. The monograph contains a complex study of physicochemical properties and characteristics of the resulting leather materials. The developed technologies were tested by the private joint-stock company Chinbar (Kyiv, Ukraine) and implemented at Ukrainian tanneries. Total number of figures – 58, tables – 95, and references – 491
A mechanically active heterotypic E-cadherin/N-cadherin adhesion enables fibroblasts to drive cancer cell invasion
Cancer-associated fibroblasts (CAFs) promote tumour invasion and metastasis. We show that CAFs exert a physical force on cancer cells that enables their collective invasion. Force transmission is mediated by a heterophilic adhesion involving N-cadherin at the CAF membrane and E-cadherin at the cancer cell membrane. This adhesion is mechanically active; when subjected to force it triggers β-catenin recruitment and adhesion reinforcement dependent on α-catenin/vinculin interaction. Impairment of E-cadherin/N-cadherin adhesion abrogates the ability of CAFs to guide collective cell migration and blocks cancer cell invasion. N-cadherin also mediates repolarization of the CAFs away from the cancer cells. In parallel, nectins and afadin are recruited to the cancer cell/CAF interface and CAF repolarization is afadin dependent. Heterotypic junctions between CAFs and cancer cells are observed in patient-derived material. Together, our findings show that a mechanically active heterophilic adhesion between CAFs and cancer cells enables cooperative tumour invasion
FORMAL METHODS: FOR ALL OR FOR CHOSEN?
Abstract: The article presents an approach to teaching formal methods that may make them accessible for ordinary software engineers, especially those who are not skilled in the underlying mathematics. The approach is based on two ideas. First, we propose modification of course contents to hide the underlying mathematical techniques under some terms and actions familiar to the engineer or student learning the corresponding application domain. This usually requires availability of mature tools supporting formal methods under consideration. Second, we modify the presentation of course material and focuse mostly on active learning and more deep students' involvement in the learning process. This approach was successfully used in traditional courses and trainings in UniTESK, a test development technology based on formal specifications