Academic literature on the topic 'Foundation plant species'

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Journal articles on the topic "Foundation plant species"

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Ellison, Aaron, Hannah Buckley, Bradley Case, Dairon Cardenas, Álvaro Duque, James Lutz, Jonathan Myers, David Orwig, and Jess Zimmerman. "Species Diversity Associated with Foundation Species in Temperate and Tropical Forests." Forests 10, no. 2 (February 5, 2019): 128. http://dx.doi.org/10.3390/f10020128.

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Foundation species define and structure ecological communities but are difficult to identify before they are declining. Yet, their defining role in ecosystems suggests they should be a high priority for protection and management while they are still common and abundant. We used comparative analyses of six large forest dynamics plots spanning a temperate-to-tropical gradient in the Western Hemisphere to identify statistical “fingerprints” of potential foundation species based on their size-frequency and abundance-diameter distributions, and their spatial association with five measures of diversity of associated woody plant species. Potential foundation species are outliers from the common “reverse-J” size-frequency distribution, and have negative effects on alpha diversity and positive effects on beta diversity at most spatial lags and directions. Potential foundation species also are more likely in temperate forests, but foundational species groups may occur in tropical forests. As foundation species (or species groups) decline, associated landscape-scale (beta) diversity is likely to decline along with them. Preservation of this component of biodiversity may be the most important consequence of protecting foundation species while they are still common.
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Valdesolo, Tommaso, Silvia Del Vecchio, and Gabriella Buffa. "Patterns of Seed Dispersal in Coastal Dune Plant Communities." Sustainability 14, no. 17 (September 2, 2022): 10983. http://dx.doi.org/10.3390/su141710983.

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Seed dispersal is a key determinant of species distribution, although it is still unclear how it contributes to species assembly in plant communities. We linked patterns of seed dispersal to coexisting species to investigate the role of dispersal in the species assembly process. We focused on 19 species coexisting in a foredune plant community, classified as “foredune foundation species”, “semi-fixed dune species,” and “alien species”. The number of seeds dispersed by the 19 species was monitored monthly in 25 plots for 12 months. Then we compared both dispersal strategies and dispersal phenology among the species. Foredune foundation species, species of the semi-fixed dune, and alien species used the same dispersal strategies, with the exception of hemerochory, which was prevalently used by alien species. The three groups of species differentiated the dispersal season: semi-fixed dune species and alien species were early and late dispersers, respectively (spring vs. late summer), while foredune foundation species dispersed seeds in summer. Seasonal differentiation in seed dispersal may play a more important role in the species assembly process than dispersal vectors. Shifts in seasonality due to climate change may influence the timing of seed dispersal and provide species with different colonization opportunities.
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Lucero, Jacob E., Taylor Noble, Stephanie Haas, Michael Westphal, H. Scott Butterfield, and Christopher J. Lortie. "The dark side of facilitation: native shrubs facilitate exotic annuals more strongly than native annuals." NeoBiota 44 (April 5, 2019): 75–93. http://dx.doi.org/10.3897/neobiota.44.33771.

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Positive interactions enhance biodiversity and ecosystem function, but can also exacerbate biological invasions. Facilitation of exotic invaders by exotic foundation species (invasional meltdown) has been studied extensively, but facilitation of exotic invaders by native foundation species has attracted less attention. Specifically, very few studies have examined the extent that native foundation species facilitate native and exotic competitors. Understanding the processes that mediate interactions between native and exotic species can help explain, predict, and improve management of biological invasions. Here, we examined the effects of native foundation shrubs on the relative abundance of the annual plant community – including native and exotic taxa – from 2015–2018 in a desert ecosystem at Carrizo Plain National Monument, California, USA (elevation: 723 m). Shrub effects varied by year and by the identity of annual species, but shrubs consistently enhanced the abundance of the annual plant community and facilitated both native (n=17 species) and exotic (n=4 species) taxa. However, at the provenance level, exotic annuals were facilitated 2.75 times stronger in abundance than native annuals, and exotic annuals were always more abundant than natives both near and away from shrubs. Our study reaffirms facilitation as an important process in the organisation of plant communities and confirms that both native and exotic species can form positive associations with native foundation species. However, facilitation by native foundation species can exacerbate biological invasions by increasing the local abundance of exotic invaders. Thus, the force of facilitation can have a dark side relevant to ecosystem function and management.
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Zerebecki, RA, AR Hughes, J. Goff, TC Hanley, W. Scheffel, and KL Heck Jr. "Effect of foundation species composition and oil exposure on wetland communities across multiple trophic levels." Marine Ecology Progress Series 662 (March 18, 2021): 53–68. http://dx.doi.org/10.3354/meps13624.

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Climate-driven range shifts can result in altered mixtures of foundation species that can affect ecosystem structure and function. Higher diversity mixed assemblages may moderate disturbance impacts, yet this prediction has rarely been tested. The Deepwater Horizon oil spill provided an opportunity to examine the effects of salt marsh foundation species identity and composition on the response of both plant and faunal communities to oil disturbance. In the northern Gulf of Mexico, salt marshes are typically dominated by the foundation species smooth cordgrass, Spartina alterniflora. However, the sub-tropical black mangrove, Avicennia germinans, is expanding northward and increasingly growing with, and even replacing, Spartina. Based on a series of field surveys in the Chandeleur Islands, Louisiana, we found that oil exposure had few impacts on the plant community 5 yr post-oiling, though oil disturbance shifted the interaction among foundation species, increasing Avicennia’s competitive advantage and likely enhancing mangrove expansion. In contrast, abundance of the epibenthic animal community was reduced by ~30% and community composition was altered at oiled sites. Mixed foundation species assemblages provided few reductions in oil impacts within either trophic level. Strong habitat associations of epibenthic taxa, coupled with oil effects on individual foundation species, likely suppressed any advantage of mixed vegetation on the associated fauna. Our survey highlights that plant and epibenthic animal responses to disturbance can be decoupled, emphasizing the importance of examining both simultaneously to better understand and predict long-term responses.
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Mukherjee, Swarnali, Rudra Prasad Das, Soumyajit Banerjee, Parthiba Basu, Goutam K. Saha, and Gautam Aditya. "Correspondence of butterfly and host plant diversity: foundation for habitat restoration and conservation." European Journal of Ecology 5, no. 1 (January 1, 2019): 49–66. http://dx.doi.org/10.2478/eje-2019-0007.

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Abstract At a spatial scale, the diversity of butterflies varies with numerous factors including the availability of the host plant species. In parity with this proposition, the correspondence of diversity of butterfly and plant in the background of the urban–rural gradient was evaluated using Kolkata, India, as a model study area. The results reveal significant positive correlation between the diversity of butterflies and the plants, with the different values for the suburban, rural, and urban areas. Identification of the butterfly loads for the plants in the respective areas can be useful in enhancing the conservation of the butterflies through enhanced plantation of the concerned plant species. Alternatively, the disclosure of the generalist and specialist pattern of the plant species preference by the butterflies may be useful in enhancing the population of the respective species in the concerned areas. The conservation strategy for butterfly species may be refined through the use of both or any one of the quantitative assessment of the butterfly–plant links in the urban–rural gradient in Kolkata, India, and similar places in the world.
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Bell, Kristian J., Tim S. Doherty, and Don A. Driscoll. "Predators, prey or temperature? Mechanisms driving niche use of a foundation plant species by specialist lizards." Proceedings of the Royal Society B: Biological Sciences 288, no. 1947 (March 31, 2021): 20202633. http://dx.doi.org/10.1098/rspb.2020.2633.

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Foundation species interact strongly with other species to profoundly influence communities, such as by providing food, refuge from predators or beneficial microclimates. We tested relative support for these mechanisms using spinifex grass ( Triodia spp.), which is a foundation species of arid Australia that provides habitat for diverse lizard communities. We first compared the attributes of live and dead spinifex, bare ground and a structurally similar plant ( Lomandra effusa ), and then tested the relative strength of association of two spinifex specialist lizard species ( Ctenophorus spinodomus and Ctenotus atlas ) with spinifex using a mesocosm experiment. Temperatures were coolest within spinifex compared to bare ground and Lomandra. Invertebrate abundance and the threat of predation were indistinguishable between treatments, suggesting temperature attenuation may be a more important driver. Overall, the dragon C. spinodomus preferred live over dead spinifex, while the skink C. atlas preferred dead spinifex, particularly at warmer air temperatures. However, both species displayed individual variability in their use of available microhabitats, with some individuals rarely using spinifex. Our results provide an example of temperature attenuation by a foundation species driving niche use by ectothermic animals.
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Lamit, L. J., T. Wojtowicz, Z. Kovacs, S. C. Wooley, M. Zinkgraf, T. G. Whitham, R. L. Lindroth, and C. A. Gehring. "Hybridization among foundation tree species influences the structure of associated understory plant communities." Botany 89, no. 3 (March 2011): 165–74. http://dx.doi.org/10.1139/b11-006.

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Understanding how genetic identity influences community structure is a major focus in evolutionary ecology, yet few studies examine interactions among organisms in the same trophic level within this context. In a common garden containing trees from a hybrid system (Populus fremontii S. Wats. × Populus angustifolia James), we tested the hypothesis that the structure of establishing understory plant communities is influenced by genetic differences among trees and explored foliar condensed tannins (CTs) and photosynthetically active radiation (PAR) as mechanisms. Several findings support our hypothesis: (i) Understory biomass and cover increase along the genetic gradient from P. angustifolia to P. fremontii. (ii) Along the same hybridization gradient, species richness decreases and species composition shifts. (iii) Populus foliar CT concentrations and PAR decrease from P. angustifolia to P. fremontii. (iv) Understory species richness increases with foliar CTs; however, biomass, cover, and composition show no relationship with CTs, and no understory variables correlate with PAR. (v) Structural equation modeling suggests that foliar CTs are a primary mechanism linking overstory tree genetics with understory richness. Using an experimental system dominated by naturally colonizing exotic species, this study demonstrates that a genetic gradient created by tree hybridization can influence understory plants.
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Gavilán, R. G., and R. M. Callaway. "Effects of foundation species above and below tree line." Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology 151, no. 4 (July 14, 2016): 665–72. http://dx.doi.org/10.1080/11263504.2016.1200687.

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Gagnon, Karine, Eli Rinde, Elizabeth G. T. Bengil, Laura Carugati, Marjolijn J. A. Christianen, Roberto Danovaro, Cristina Gambi, et al. "Facilitating foundation species: The potential for plant–bivalve interactions to improve habitat restoration success." Journal of Applied Ecology 57, no. 6 (April 6, 2020): 1161–79. http://dx.doi.org/10.1111/1365-2664.13605.

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Travis, Steven E., and C. Edward Proffitt. "Genotypic interactions limit growth and stimulate flowering in a salt marsh foundation plant species." Perspectives in Plant Ecology, Evolution and Systematics 18 (February 2016): 33–44. http://dx.doi.org/10.1016/j.ppees.2016.01.002.

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Dissertations / Theses on the topic "Foundation plant species"

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Pearce, Madison Natasha. "Laying the Foundation for a Fremont Phytolith Typology Using Select Plant Species Native to Utah County." BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6648.

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Archaeobotanical evidences for the presence of wild plants at Fremont archaeological sites are numerous. However, little can be positively argued for why those plants are present, if they were used by site inhabitants, and how they were used. Additionally, there are likely several wild plants that were used but that do not appear in the archaeobotanical record as pollen or macrobotanicals, the two most commonly identified plant remains. I argue that it is possible to provide better interpretations for how and why the Fremont used plants by researching how their historic counterparts, the Goshute, Shoshone, Ute, and Southern Paiute, used the same plants that are identified at prehistoric sites. I further argue that a phytolith typology for Fremont archaeology can provide more insight into prehistoric plant use. I demonstrate its utility through a phytolith analysis of ground stone tools from Wolf Village, a Fremont site in Utah County.
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Coutinho, M., and Lori J. Marks. "Classroom Based Performance Assessments: Using Standards and Lesson Plans to Accommodate Academic Diversity Among Students." Digital Commons @ East Tennessee State University, 1995. https://dc.etsu.edu/etsu-works/3572.

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Roy, Julien. "Microbiologie des plantes en coussin des milieux alpins : influence des facteurs biotiques et abiotiques dans l'assemblage des communautés microbiennes." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENV024/document.

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Les microorganismes occupent une place centrale dans la diversité du vivant et les processus écosystémiques, notamment dans le sol où ils sont en interaction avec les plantes. Cette thèse vise à caractériser l'influence respective des plantes et du contexte abiotique dans la distribution spatiale des microorganismes. Le travail s'appuie sur un modèle simplifié de la biologie des sols, les plantes en coussins des falaises de haute montagne. Nous avons suivi une seule espèce aux morphotypes variés, Silene acaulis, une espèce ingénieure de l'écosystème dont la croissance mène à la création d'un sol de novo. L'échantillonnage comprend le prélèvement de sol de plante et de sol extérieur comme témoin, pour des coussins distribués le long de gradients altitudinaux et géologiques. Des méthodes moléculaires ont été utilisées pour décrire la diversité microbienne et le génotypage des coussins.Les coussins structurent la beta diversité bactérienne et fongique à l'échelle régionale en agissant comme un tampon à échelle locale sur les effets de la roche mère et de l'altitude en homogénéisant le pH et par un apport de nutriments. Cet effet ingénieur est d'autant plus fort que la contrainte abiotique augmente et varie selon le génotype des coussins. La beta diversité bactérienne diffère de la beta diversité fongique. Alors que les communautés bactériennes sont sensibles au pH du sol et convergent sous les coussins, les communautés fongiques sont corrélées à la génétique des coussins, particulièrement les clades aux modes de vie biotrophes/pathogènes. Ce travail montre que les plantes sont un filtre biotique majeur de la biogéographie microbienne
Microorganisms are key component of Hearth biodiversity and ecosystem processes, especially in soils where they interact with plants. The objectives of the PhD was to caracterize the plant and abiotic respective influence on microbial spatial distribution. The work was based on a simplified soil biology model, the alpine cushion plants. We choose one species composed of variable morphotype, Silene acaulis,can ecosystem engineer species that creates de novo soil through growth. Sampling design includes soil within cushions and outside, spanning altitudinal and geological gradients. Molecular approachs were used to describe diversity and to genotype cushions.Cushions structures bacterial and fungal regional beta diversity through a local buffering of the influence of abiotic context, homogeneizing soil pH and by nutrient supply. This engineering effect increased in stressful conditions and varied according to plant genotype. Betadiversity differed between bacteria and fungi. Bacterial communities are mainly influenced by pH and converge within cushions while fungal communities correlate to cushion genetic, especially plant-associated biotrophs fungal clades. This work shows that plants act as a major biotic filter on microbial biogeography
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Mims, Pamela J. "The Importance of Implementing Systematic Instruction Plans for Students with Significant Disabilities." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/203.

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Nyarambi, Arnold. "Conducting Functional Behavior Assessments and Implementing Behavior Intervention Plans: Challenges That Novice Teacher Candidates Have to Navigate." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/8272.

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Fox, James J., Leia Blevins, H. Boreing, and M. Barrow. "Analysis of Functional Behavior Assessments and Intervention Plans Conducted by School-based Teams." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/157.

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A case study of FBAs conducted by school-based teams analyzed 26 complete FBAs from rural LEAs trained by a university-based PBIS project staff. Interviews and observations were more often used than instruments/procedures. School teams initiated FBAs quicker but took longer to complete than did independent consultants. Researchers and practitioners will identify essential FBA components; how FBAs can be analyzed per these components; describe study results; and, discuss implications for research and application.
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Kozla, Dávid. "Stavebně technologický projekt pro Mezinárodní centrum klinického výzkumu Fakultní nemocnice u sv. Anny v Brně." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2020. http://www.nusl.cz/ntk/nusl-409970.

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This diploma thesis solves the construction technology project of the International Clinical Research Center of the St. Anne’s University Hospital, Brno (ICRC), namely the first stage of the construction of the buildings "B1" and "C1". It tries to design an ideal technological process of construction with respect of local conditions. Technologically it focuses mainly on the issue of special foundation, namely protection of excavation pit with secant pile wall and pile foundation. There are processed technological regulations, time and financial plans, construction budget, control and test plan, plan of heavy equipment and safety or environmental requirements. Everything is supplemented by attachments and drawing documentation.
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Malaník, Jan. "Stavebně technologický projekt bytového domu v Brně." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227544.

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The thesis contains analysis earthworks, foundations, carcass substructure of residential house on the street Kopečná 9 in Brno. The work also includes gradual changes in site equipment, detailed schedule of work for selected works, rough schedule of the whole building, construction budget, site equipment budget and details of construction. Specialization in the work addresses the specific use of roads and traffic signs.
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Sethosa, Mosima Francisca. "Assisting teachers to support mildly intellectually disabled learners in the foundation phase in accordance with the policy of inclusion." Thesis, 2001. http://hdl.handle.net/10500/17719.

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Mildly intellectually disabled (MID) learners, in South Africa, experience a great deal of discrimination. For the Black MID learner, the situation has been the worst in that even at a time when their white counterparts received education in separate schools, nothing of the sort existed for them. Most of them found themselves in ordinary schools, a situation described by many authors as "mainstreaming by default". The new education dispensation of 1994 brought along with it the need to begin looking at ways in which these learners are to be accommodated in the education system. However, such accommodation is made difficult by the fact that teachers are not familiar with ways of catering for diversity in the classrooms. An investigation was undertaken of the phenomenon mild intellectual disability. The characteristics of these learners were studied, in order to understand how these characteristics impact on their learning. The teaching principles and learning principles that make it easier for them to learn were studied. Most of these learners experience problems with reading, writing and mathematics. Existing educational programmes in developed and developing countries were examined, together with aspects of those programmes that might be of use in South Africa. A closer look was taken at provisions for these learners in South Africa before the new dispensation. An empirical study was undertaken to investigate what manifestations these learners display, how they are assisted once they are identified and to establish if teachers receive any support from parents, school management teams and the Department of Education. Finally, it was investigated if methods used for Outcomes-Based Education can be used to accommodate MID learners. Implications were then tabled on three levels, namely, the macro level, which is the provincial level, where decisions regarding educational policy and legislation for the Province are made, the meso level, which concerns implementation at the district level, and the micro level, which is the school itself. This level concerns the teacher's task in the classroom. Finally, a training manual for school support teams was designed, tested and finalised as a document to be used in assisting teachers to support MID learners
Early Childhood Education and Development
D. Ed. (Special Needs Education)
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Books on the topic "Foundation plant species"

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Gail, Goldberg, and British Nutrition Foundation, eds. Plants: Diet and health : the report of a British Nutrition Foundation Task Force. Oxford: Blackwell Science for the British Nutrition Foundation, 2003.

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Komarova, Valentina, Svetlana Narutto, Yuliya Torop, Natal'ya Taeva, Aleksandr Ponomarenko, Andrey Budaev, Natal'ya Sokolova, Aleksey Osavelyuk, Ol'ga Rybakova, and Mihail Mityukov. Constitutional judicial process. ru: INFRA-M Academic Publishing LLC., 2023. http://dx.doi.org/10.12737/2104323.

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In the textbook, from the standpoint of the current state of the science of constitutional law and taking into account the competence-based approach to mastering the knowledge of the discipline "Constitutional Judicial process", the material and procedural foundations of the constitutional judicial process at the federal level, in the subjects of the Russian Federation, special attention is paid to the experience of foreign countries and issues of interaction with international judicial bodies. Topical issues of the theory and practice of constitutional justice of modern Russia are highlighted. For students and teachers of law and other educational institutions whose plans provide for the teaching of the constitutional judicial process; scientists and practitioners.
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Olafsson, Emil. Marine Macrophytes As Foundation Species. Taylor & Francis Group, 2021.

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Olafsson, Emil. Marine Macrophytes As Foundation Species. Taylor & Francis Group, 2016.

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Olafsson, Emil. Marine Macrophytes As Foundation Species. Taylor & Francis Group, 2016.

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Olafsson, Emil. Marine Macrophytes As Foundation Species. Taylor & Francis Group, 2016.

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Olafsson, Emil. Marine Macrophytes As Foundation Species. Taylor & Francis Group, 2016.

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Marine Macrophytes As Foundation Species. Taylor & Francis Group, 2016.

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Computer Learning Foundation: Special education lesson plans. Palo Alto, CA: Computer Learning Foundation, 1989.

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Goldberg, Gail Lynn, and British Nutrition Foundation. Plants: Diet and Health (British Nutrition Foundation). Blackwell Publishing, Incorporated, 2002.

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Book chapters on the topic "Foundation plant species"

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Brown, Gary, and Gary R. Feulner. "The Vascular Flora of the United Arab Emirates." In A Natural History of the Emirates, 387–425. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-37397-8_13.

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AbstractThis chapter discusses the flora of the United Arab Emirates (UAE), focusing on various aspects of the individual plant species. A brief overview of salient features of the flora is given in terms of species number and families, followed by a short discussion regarding some of the taxonomic problems surrounding the naming and identification of species. With respect to biogeographical aspects, it is emphasised that the current flora of the nation represents a distinct snapshot in time that has been shaped by a diversity of events in the past, all of which continue to operate on different spatio-temporal scales. After a brief discussion of keystone and foundation species in the UAE desert, autecological aspects are examined, as these are fundamental to understanding the response of plants to a changing environment. Following on from this topic, the concepts of life forms, plant functional groups and plant strategies are touched upon. In the final section, some remarkable features of the reproductive biology of desert plants are described. Chapter 5 examines the typical plant communities and also looks at the main threats to the flora and vegetation of the country.
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Rees, Paul A. "Pest, weed and disease management." In Key questions in applied ecology and conservation: a study and revision guide, 90–105. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789248494.0090.

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Abstract This chapter contains questions about pests and weeds and their control, invasive species, parasites, and animal and plant diseases. The questions are arranged by topic and divided into three levels: foundation, intermediate and advanced.
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Thomsen, Mads, Thomas Wernberg, Peter Staehr, and David Schiel. "Ecological Interactions between Marine Plants and Alien Species." In Marine Macrophytes as Foundation Species, 226–49. Taylor & Francis Group, 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487-2742: CRC Press, 2016. http://dx.doi.org/10.4324/9781315370781-11.

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Thiel, Martin, and Ceridwen Fraser. "The Role of Floating Plants in Dispersal of Biota Across Habitats and Ecosystems." In Marine Macrophytes as Foundation Species, 76–94. Taylor & Francis Group, 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487-2742: CRC Press, 2016. http://dx.doi.org/10.4324/9781315370781-5.

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Cohan, Frederick M. "Genomes reveal the cohesiveness of bacterial species taxa and provide a path towards describing all of bacterial diversity." In Trends in the systematics of bacteria and fungi, 282–300. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789244984.0282.

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Abstract This book chapter argues that bacterial systematists of the mid-20th century fortuitously created a species-level systematics that actually fits an important universal theory of speciation by discussing taxonomy would allow us to infer the important characteristics of any unknown organism once we classify it to species. It turns out, unexpectedly, that bacterial species taxa share a species-like property with the species taxa of zoology and botany. While recombination within species taxa of all these groups fails to prevent diversification within species, recombination nevertheless appears to act universally as a force of cohesion within species taxa. That is, recurrent recombination within species limits neutral sequence divergence within species taxa of plants, animals, and bacteria; recombination also allows a sharing of generally adaptive genes across a species range. The 95% ANI criterion that demarcates the traditionally defined species taxa of bacteria fortuitously also yields groups of bacteria that are subject to the species-like property of cohesion, where recombination prevents neutral sequence divergence among ecotypes within a species. Use of the ANI criterion, then, not only provides an easily used algorithm for demarcating bacterial species; it also places bacterial demarcation on the same theory-based foundation as the species taxonomy of animals and plants.
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Heleno, Ruben H. "The effect of non-native plant invasions on the dispersal of native seeds." In Plant invasions: the role of biotic interactions, 256–69. Wallingford: CABI, 2020. http://dx.doi.org/10.1079/9781789242171.0256.

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Abstract Non-native plants change the communities they integrate in multiple ways, including direct and indirect effects on co-occurring native vegetation. While direct effects are more obvious, indirect effects, i.e. those mediated by biotic interactions with other trophic levels, can also have pervasive consequences for long-term community persistence. Seed dispersal is a critical stage during the life cycle of most plants, as it lays the foundations for plant recruitment patterns and long-term vegetation dynamics. By interacting with seed-dispersing animals, primarily frugivorous birds and mammals, plants can positively or negatively affect the dispersal of co-occurring native seeds. In an increasingly invaded world, it is thus critically important to identify general trends on the direction and magnitude of these effects. This chapter reviews the empirical evidence supporting such changes and the potential underlying mechanisms driving them. While the direct impacts of plant invasions are relatively easy to document, indirect effects are much harder to detect. Nevertheless, the most important consequence of the incorporation of new fruiting plants into native communities seems to be a direct competition for the services provided by the local dispersers, negatively affecting native seed dispersal rates. However, another key message emerging from the literature is that responses are highly idiosyncratic, and usually habitat- and species-specific, and therefore resistant to broad generalizations. Fruiting phenology, and in particular the synchrony/asynchrony between the availability of native and non-native fruits, seems to be a particularly important driver of the direction of the responses (i.e. towards facilitation or competition). However, most evidence is still derived from anecdotal observations and formal community level assessments are largely missing. Similarly, how invasive plants change the emergent structure of seed dispersal networks remains uncertain, with early evidence suggesting that novel seed dispersal networks might be structurally very similar to native ones. Bringing together classic experimental designs and new technical and analytical tools to provide broad synthesis will be vital in the near future to clarify the direction, magnitude and generality of these effects.
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Poleshchuk, Olga, and Evgeny Komarov. "Clustering of the State of Plant Species in the Urban Environment Under Z-Information." In Recent Developments and the New Directions of Research, Foundations, and Applications, 261–70. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-20153-0_20.

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Schelhas, John, Janice Alexander, Mark Brunson, Tommy Cabe, Alycia Crall, Michael J. Dockry, Marla R. Emery, et al. "Social and Cultural Dynamics of Non-native Invasive Species." In Invasive Species in Forests and Rangelands of the United States, 267–91. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-45367-1_12.

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AbstractInvasive species and their management represent a complex issue spanning social and ecological systems. Invasive species present existing and potential threats to the nature of ecosystems and the products and services that people receive from them. Humans can both cause and address problems through their complex interactions with ecosystems. Yet, public awareness of invasive species and their impact is highly uneven, and public support for management and control of invasive species can be variable. Public perceptions often differ markedly from the perspectives of concerned scientists, and perceptions and support for management are influenced by a wide range of social and ecological values. In this chapter, we present a broad survey of social science research across a diversity of ecosystems and stakeholders in order to provide a foundation for understanding the social and cultural dimensions of invasive species and plan more effective management approaches. This chapter also addresses tribal perspectives on invasive species, including traditional ecological knowledge, unique cultural dimensions for tribes, and issues critical to engaging tribes as partners and leaders in invasive species management. Recognizing that natural resource managers often seek to change people’s perceptions and behaviors, we present and discuss some promising approaches that are being used to engage human communities in ways that empower and enlist stakeholders as partners in management.
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McNew, Lance B., David K. Dahlgren, and Jeffrey L. Beck. "Introduction to Rangeland Wildlife Ecology and Conservation." In Rangeland Wildlife Ecology and Conservation, 1–6. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-34037-6_1.

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AbstractRangelands are vast, dynamic, and integral to providing habitat for thousands of vertebrate and invertebrate species, while concurrently serving as the foundation of human food and fiber production in western North America. Reciprocally, wildlife species provide critical services that maintain functional rangeland ecosystems. Therefore, human management of rangelands via fire, grazing, agricultural programs, and policy can enhance, disturb, or inhibit the necessary interactions among natural processes of plants and animals that maintain rangeland ecosystems. As conservation issues involving rangelands have grown in societal awareness and complexity, rangeland managers, wildlife biologists, and others have discovered the need to work more closely together with an increasingly holistic approach, spurring a rapid accumulation of rangeland wildlife information in the early twenty-first century. This book represents a synthesis of contemporary knowledge on rangeland wildlife conservation and ecology. Accordingly, we provide a review of the state of science for new, as well as seasoned, wildlife and rangeland professionals who have stewardship of North America’s most undervalued ecosystem.
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Li, Le, Trude Schwarzacher, Paulina Tomaszewska, Qing Liu, Xiaoyu Zoe Li, Kexian Yi, Weihuai Wu, and J. S. Pat Heslop-Harrison. "Protocols for Chromosome Preparations: Molecular Cytogenetics and Studying Genome Organization in Coffee." In Mutation Breeding in Coffee with Special Reference to Leaf Rust, 291–314. Berlin, Heidelberg: Springer Berlin Heidelberg, 2023. http://dx.doi.org/10.1007/978-3-662-67273-0_21.

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AbstractCytological preparations from cell nuclei are required to count the number of chromosomes (including determining ploidy or aneuploidy), to investigate their morphology and organization. The results are valuable for genetic and evolutionary studies, and in breeding programs to understand species relationships, polyploidy, and potential introgression of chromosomes in hybrids between different species. Preparation of good chromosome spreads with well-separated metaphase chromosomes is the foundation of cytogenetic research including chromosomal mapping based on FISH (fluorescence in situ hybridization). FISH combined with specific locus probes correlated with molecular markers to specific chromosomes for integrating physical and linkage maps as well as studying the genetic evolution of allopolyploidization, has rarely been applied in Coffea spp. despite being a global high-value crop. Cytogenetic studies of Coffea are limited by the small size and similar morphology of the chromosomes, but FISH can help to map sequences to chromosome arms and identify individual chromosomes. This chapter presents protocols for germinating seeds and growing coffee plants involving pre-treatment and fixation of root-tips where the meristems of actively growing roots have many divisions. Mitotic metaphase chromosome preparation on microscope slides is described, as well as preparing probes of 5S and 18S rDNA to be used for FISH. The FISH experiments involve a two-step protocol with pre-treatments and setting up the hybridization on day 1 and the detection of probe sites on day 2 after overnight hybridization. A final section gives advice about visualization using a fluorescent microscope and capturing images.
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Conference papers on the topic "Foundation plant species"

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Yan, Y., A. Laskar, Z. Cheng, F. Menq, Y. Tang, Y. L. Mo, and Z. Shi. "Periodic Materials-Based 3D Seismic Base Isolators for Nuclear Power Plants." In ASME 2014 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/pvp2014-28611.

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The concept of periodic materials, based on solid state physics theory, is applied to earthquake engineering. The periodic material is a material which possesses distinct characteristics that do not allow waves with certain frequencies to be transmitted through; therefore, this material can be used in structural foundations to block unwanted seismic waves with certain frequencies. The frequency band of periodic material that can filter out waves is called the band gap, and the structural foundation made of periodic material is referred to as the periodic foundation. In designing a periodic foundation, the first step is to match band gaps of the periodic foundation with the natural frequencies of the superstructure. This is an iterative process. Starting with a design of the periodic foundation, the band gaps are identified by performing finite element analyses using ABAQUS. This design process is repeated until the band gaps match natural frequencies of the superstructure, and the field tests of a scaled specimen are conducted to validate the design. This is an on-going research project. Presented in this paper are the preliminary results, which show that the three dimensional periodic foundation is a promising and effective way to mitigate structural damage caused by earthquake excitations.
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Ramenskaya, A., Svetlana Degtyareva, and Valentina Dorofeeva. "ECOLOGICAL BASIS FOR THE CREATION OF BIOSPHERE RESERVES OF THE RUSSIAN FEDERATION." In Modern problems of animal and plant ecology. FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov, 2021. http://dx.doi.org/10.34220/mpeapw2021_56-59.

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The ecological foundations of the creation of some biosphere reserves of the Russian Federation are analyzed. The article focuses on the influence of abiotic environmental factors on the species of organisms and ecosystems in general. The patterns of vegetation distribution, the time of creation and the functional role of the reserve, and the status of the biosphere reserve are revealed.
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Mohammadi, Meisam, A. R. Saidi, and Mehdi Mohammadi. "Buckling Analysis of Thin Functionally Graded Rectangular Plates Resting on Elastic Foundation." In ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2010. http://dx.doi.org/10.1115/esda2010-24594.

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In the present article, the buckling analysis of thin functionally graded rectangular plates resting on elastic foundation is presented. According to the classical plate theory, (Kirchhoff plate theory) and using the principle of minimum total potential energy, the equilibrium equations are obtained for a functionally graded rectangular plate. It is assumed that the plate is rested on elastic foundation, Winkler and Pasternak elastic foundations, and is subjected to in-plane loads. Since the plate is made of functionally graded materials (FGMs), there is a coupling between the equations. In order to remove the existing coupling, a new analytical method is introduced where the coupled equations are converted to decoupled equations. Therefore, it is possible to solve the stability equations analytically for special cases of boundary conditions. It is assumed that the plate is simply supported along two opposite edges in x direction and has arbitrary boundary conditions along the other edges (Levy boundary conditions). Finally, the critical buckling loads for a functionally graded plate with different boundary conditions, some aspect ratios and thickness to side ratios, various power of FGM and foundation parameter are presented in tables and figures. It is concluded that increasing the power of FGM decreases the critical buckling load and the load carrying capacity of plate increases where the plate is rested on Pasternak in comparison with the Winkler type.
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Mellenthin Filardo, Martina, Rohith Akula, Tino Walther, and Hans-Joachim Bargstädt. "Automated framework for optimized path-planning for pile foundation drilling machines based on 4D BIM modelling." In IABSE Congress, Ghent 2021: Structural Engineering for Future Societal Needs. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2021. http://dx.doi.org/10.2749/ghent.2021.1949.

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<p>While the Building Information Modeling (BIM) method allows accurate information modelling and thus more robust predictions, it often needs to be combined with tasks beyond the model or modelling phase, especially if the goal is a model-based construction phase. This study proposes an optimization workflow for the construction of pile foundations, since they are part of a varying range of building and infrastructure projects. Pile foundation drilling is an extensive construction process, which can be optimized significantly by reducing the execution length through an effective drilling path plan and automated data transfer. This was achieved through the combination of optimization algorithms, which were linked to the 3D BIM model and selected the shortest distance between piles using Ant Colony Optimization (ACO) algorithm, based on the Travelling Salesperson Problem (TSP). Subsequently the script created separate security distance-compliant tours for drilling machines, calculated construction times and converted the resulting paths into schedules, which in turn could be updated to the 3D BIM model to generate a 4D animation of the construction process. The developed optimization framework and script were tested with a construction company focused on special foundations based in Germany.</p>
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Mellenthin Filardo, Martina, Rohith Akula, Tino Walther, and Hans-Joachim Bargstädt. "Automated framework for optimized path-planning for pile foundation drilling machines based on 4D BIM modelling." In IABSE Congress, Ghent 2021: Structural Engineering for Future Societal Needs. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2021. http://dx.doi.org/10.2749/ghent.2021.1949.

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<p>While the Building Information Modeling (BIM) method allows accurate information modelling and thus more robust predictions, it often needs to be combined with tasks beyond the model or modelling phase, especially if the goal is a model-based construction phase. This study proposes an optimization workflow for the construction of pile foundations, since they are part of a varying range of building and infrastructure projects. Pile foundation drilling is an extensive construction process, which can be optimized significantly by reducing the execution length through an effective drilling path plan and automated data transfer. This was achieved through the combination of optimization algorithms, which were linked to the 3D BIM model and selected the shortest distance between piles using Ant Colony Optimization (ACO) algorithm, based on the Travelling Salesperson Problem (TSP). Subsequently the script created separate security distance-compliant tours for drilling machines, calculated construction times and converted the resulting paths into schedules, which in turn could be updated to the 3D BIM model to generate a 4D animation of the construction process. The developed optimization framework and script were tested with a construction company focused on special foundations based in Germany.</p>
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Nawrotzki, Peter. "Earthquake Protection Strategies for Power Plant Equipment." In ASME 2009 Power Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/power2009-81161.

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Power plant machinery can be dynamically decoupled from the substructure by the effective use of helical steel springs and viscous dampers. Turbine foundations, coal mills, boiler feed pumps and other machine foundations benefit from this type of elastic support systems to mitigate the transmission of operational vibration. The application of these devices may also be used to protect against earthquakes and other catastrophic events, i.e. airplane crash, of particular importance in nuclear facilities. This article illustrates basic principles of elastic support systems and applications on power plant equipment and buildings in medium and high seismic areas. Spring-damper combinations with special stiffness properties are used to reduce seismic acceleration levels of turbine components and other safety or non-safety related structures. For turbine buildings, the integration of the turbine substructure into the machine building can further reduce stress levels in all structural members. The application of this seismic protection strategy for a spent fuel storage tank in a high seismic area is also discussed. Safety in nuclear facilities is of particular importance and recent seismic events and the resulting damage in these facilities again brings up the discussion. One of the latest events is the 2007 Chuetsu earthquake in Japan. The resulting damage in the Kashiwazaki Kariwa Nuclear Power Plant can be found in several reports. Among other vital components, turbine equipment was damaged and overflow of fuel storage pools was observed (Fukushima, 2007 and Yamashita, 2008).
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Milanesi, Riccardo R., Maithree Kurukulasuriya, Davide Bolognini, Luca Grottoli, Filippo Dacarro, and Paolo Morandi. "EXPERIMENTAL INVESTIGATION OF SEISMIC BEHAVIOUR OF EXISTING MASONRY INFILLS." In 2nd Croatian Conference on Earthquake Engineering. University of Zagreb Faculty of Civil Engineering, 2023. http://dx.doi.org/10.5592/co/2crocee.2023.55.

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The seismic vulnerability of masonry infills has been observed persistently during post seismic surveys, and their seismic behaviour has been investigated for decades due to its complexity involving different aspects that need to be addressed and the diversity of existing masonry infill typologies. Despite the copious experimental studies conducted, only a few of them had the opportunity to analyse different aspects of the same masonry typology due to the reduced number of specimens usually involved in a testing campaign. The out-of-plane response of masonry infills, and the reduction of the out-of-plane resistance of the infill panels due to the damage caused by in-plane deformations, are usually the most critical aspects regarding life safety. Furthermore, the out-of-plane experimental tests on masonry infills have almost always been conducted through pseudo-static tests with different loading techniques (4 point loading, central loading, constant pressure with airbags or other systems), meanwhile a complete experimental campaign on existing masonry infills through dynamic tests on a shaking table has not taken place yet. Within this framework, an experimental campaign focusing on non-ductile infill specimens made of horizontally hollowed weak clay units representing one of the most common infill systems present in Italy, is currently ongoing at the Eucentre Foundation of Pavia. In the present paper, the results from the first phase of the ongoing study will be discussed. In the scope of this research program, in-plane cyclic tests and out-of-plane dynamic tests are conducted on full-scale infill panels built inside single storey single bay composite steel/reinforced concrete frames, along with tests of characterization of the masonry materials. The first phase of tests included five specimens, four of them built with all edges bonded to the frame and one specimen with free vertical edges. The four specimens with the same boundary conditions were used to characterize the pure in-plane behaviour, the pure out-of-plane behaviour, and the out-of-plane behaviour with previous in-plane damage. The specimen with the vertical edges free was subjected to pure out-of-plane excitation to explore the one-way bending/arching behaviour of infills.
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Rigo, Ana, Igor Majstorović, and Željko Stepan. "Challenges of developing Transport Master Plan." In 7th International Conference on Road and Rail Infrastructure. University of Zagreb Faculty of Civil Engineering, 2022. http://dx.doi.org/10.5592/co/cetra.2022.1424.

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A transport master plan is a strategic document that aims to achieve an efficient and sustainable transport system that is in line with the needs of the economy and residents in the study area. A master plan represents a strategic foundation for all future transport projects, which speeds up preparation and increases the probability of their funding from European funds or other sources of financing. Methodologically, the development of a transport master plan involves data collection, traffic surveys research, traffic model development, transport system analysis and assessment, definition transport system development objectives definition, and finding measures that achieve the set objectives. So far, a dozen transport master plans have been developed in the territory of the Republic of Croatia, covering the area of single functional region (multiple counties), county or city. The paper presents a comparison as well as a critical review of developed transport master plans. Special accent is placed on the methodology for the development of the traffic model, as a basic tool for the transport system analysis and testing the scenarios for the future transport system development. The paper emphasizes the need to involve all stakeholders and interested public through the whole process of developing master plan.
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Yang, Qiang. "Research on Smart Nuclear Power Construction Based on Digitalization and System Engineering in TNPS." In 2022 29th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/icone29-91570.

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Abstract In order to solve the digital transformation problems faced by Jiangsu Nuclear Power Station (TNPS) under the complex situation, and to benchmark advanced enterprises to improve the current digitalization level, TNPS established a special organization to carry out the V-type system construction method which covers user needs, functional requirements, architecture design, detailed design, code implementation, unit testing, integration testing, system testing, acceptance testing, etc. TNPS is carrying out the top-level design and application implementation of intelligent station, support platform and network construction and existing information systems based on the foundation functional and digital transformation, smart application and decision-making platform construction as the main body of the smart power plant implementation plan, and combed the application scenarios from the four dimensions of “personnel, equipment, environment, and operation”, and introduced smart nuclear power using smart construction sites and smart outage as examples Implementation content and solutions for typical applications. This work has advanced design and complete system, which has certain reference significance for nuclear power enterprises to carry out digital and intelligent transformation.
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Tabatabaie, Mansour, and Thomas Ballard. "Time-Domain Nonlinear SSI Analysis of Foundation Sliding Using Frequency-Dependent Foundation Impedance Derived From SASSI." In ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61556.

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Dynamic soil-structure interaction (SSI) analysis of nuclear power plants is often performed in frequency domain using programs such as SASSI [1]. This enables the analyst to properly a) address the effects of wave radiation in an unbounded soil media, b) incorporate strain-compatible soil shear modulus and damping properties and c) specify input motion in the free field using the de-convolution method and/or spatially variable ground motions. For structures that exhibit nonlinearities such as potential base sliding and/or uplift, the frequency-domain procedure is not applicable as it is limited to linear systems. For such problems, it is necessary to solve the problem in the time domain using the direct integration method in programs such as ADINA [2]. The authors recently introduced a sub-structuring technique called distributed parameter foundation impedance (DPFI) model that allows the structure to be partitioned from the total SSI system and analyzed in the time domain while the foundation soil is modeled using the frequency-domain procedure [3]. This procedure has been validated for linear systems. In this paper we have expanded the DPFI model to incorporate nonlinearities at the soil/structure interface by introducing nonlinear shear and normal springs arranged in series between the DPFI and structure model. This combination of the linear far-field impedance (DPFI) plus nonlinear near-field soil springs allows the foundation sliding and/or uplift behavior be analyzed in time domain while maintaining the frequency-dependent stiffness and radiation damping nature of the far-field foundation impedance. To check the accuracy of this procedure, a typical NPP foundation mat supported at the surface of a layered soil system and subjected to harmonic forced vibration was first analyzed in the frequency domain using SASSI to calculate the target linear response and derive a linear, far-field DPFI model. The target linear solution was then used to validate two linear time-domain ADINA models: Model 1 consisting of the mat foundation+DPFI derived from the linear SASSI model and Model 2 consisting of the total SSI system (mat foundation plus a soil block). After linear alignment, the nonlinear springs were added to both ADINA models and re-analyzed in time domain. Model 2 provided the target nonlinear solution while Model 1 provided the results using the DPFI+nonlinear springs. By increasing the amplitude of the vibration load, different levels of foundation sliding were simulated. Good agreement between the results of two models in terms of the displacement response of the mat and cyclic force-displacement behavior of the springs validates the accuracy of the procedure presented herein.
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Reports on the topic "Foundation plant species"

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Leis, Sherry, Mike DeBacker, Lloyd Morrison, Gareth Rowell, and Jennifer Haack. Vegetation community monitoring protocol for the Heartland Inventory and Monitoring Network: Narrative, Version 4.0. Edited by Tani Hubbard. National Park Service, November 2022. http://dx.doi.org/10.36967/2294948.

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Native and restored plant communities are part of the foundation of park ecosystems and provide a natural context to cultural and historical events in parks throughout the Heartland Inventory and Monitoring Network (HTLN). Vegetation communities across the HTLN are primarily of three types: prairie, woodland, and forest. Park resource managers need an effective plant community monitoring protocol to guide the development and adaptation of management strategies for maintaining and/or restoring composition and structure of prairies, woodland, and forest communities. Our monitoring design attempts to balance the needs of managers for current information and the need for insight into the changes occurring in vegetation communities over time. This monitoring protocol consists of a protocol narrative (this document) and 18 standard operating procedures (SOPs) for monitoring plant communities in HTLN parks. The scientific objectives of HTLN plant community monitoring are to (1) describe the species composition, structure, and diversity of prairie, woodland, and forested communities; (2) determine temporal changes in the species composition, structure and diversity of prairie, woodland, and forested communities; and (3) determine the relationship between temporal and spatial changes and environmental variables, including specific management practices where possible. This protocol narrative describes the sampling design for plant communities, including the response design (data collection methods), spatial design (distribution of sampling sites within a park), and revisit design (timing and frequency of monitoring visits). Details can be found in the SOPs, which are listed in the Revision History section and available at the Integrated Resource Management Applications (IRMA) website (irma.nps.gov). Other aspects of the protocol summarized in the narrative include procedures for data management and reporting, personnel and operating requirements, and instructions for how to revise the protocol.
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Fluhr, Robert, and Volker Brendel. Harnessing the genetic diversity engendered by alternative gene splicing. United States Department of Agriculture, December 2005. http://dx.doi.org/10.32747/2005.7696517.bard.

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Our original objectives were to assess the unexplored dimension of alternative splicing as a source of genetic variation. In particular, we sought to initially establish an alternative splicing database for Arabidopsis, the only plant for which a near-complete genome has been assembled. Our goal was to then use the database, in part, to advance plant gene prediction programs that are currently a limiting factor in annotating genomic sequence data and thus will facilitate the exploitation of the ever increasing quantity of raw genomic data accumulating for plants. Additionally, the database was to be used to generate probes for establishing high-throughput alternative transcriptome analysis in the form of a splicing-specific oligonucleotide microarray. We achieved the first goal and established a database and web site termed Alternative Splicing In Plants (ASIP, http://www.plantgdb.org/ASIP/). We also thoroughly reviewed the extent of alternative splicing in plants (Arabidopsis and rice) and proposed mechanisms for transcript processing. We noted that the repertoire of plant alternative splicing differs from that encountered in animals. For example, intron retention turned out to be the major type. This surprising development was proven by direct RNA isolation techniques. We further analyzed EST databases available from many plants and developed a process to assess their alternative splicing rate. Our results show that the lager genome-sized plant species have enhanced rates of alternative splicing. We did advance gene prediction accuracy in plants by incorporating scoring for non-canonical introns. Our data and programs are now being used in the continuing annotation of plant genomes of agronomic importance, including corn, soybean, and tomato. Based on the gene annotation data developed in the early part of the project, it turned out that specific probes for different exons could not be scaled up to a large array because no uniform hybridization conditions could be found. Therefore, we modified our original objective to design and produce an oligonucleotide microarray for probing alternative splicing and realized that it may be reasonable to investigate the extent of alternative splicing using novel commercial whole genome arrays. This possibility was directly examined by establishing algorithms for the analysis of such arrays. The predictive value of the algorithms was then shown by isolation and verification of alternative splicing predictions from the published whole genome array databases. The BARD-funded work provides a significant advance in understanding the extent and possible roles of alternative splicing in plants as well as a foundation for advances in computational gene prediction.
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Chen, Junping, Zach Adam, and Arie Admon. The Role of FtsH11 Protease in Chloroplast Biogenesis and Maintenance at Elevated Temperatures in Model and Crop Plants. United States Department of Agriculture, May 2013. http://dx.doi.org/10.32747/2013.7699845.bard.

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specific objectives of this proposal were to: 1) determine the location, topology, and oligomerization of FtsH11 protease; 2) identify the substrate/s of FtsH11 and the downstream components involved in maintaining thermostability of chloroplasts; 3) identify new elements involved in FtsH11 protease regulatory network related to HT adaptation processes in chloroplast; 4) Study the role of FtsH11 homologs from crop species in HT tolerance. Background to the topic: HT-tolerant varieties that maintain high photosynthetic efficiency at HT, and cope better with daily and seasonal temperature fluctuations are in great need to alleviate the effect of global warming on food production. Photosynthesis is a very complex process requiring accurate coordination of many complex systems and constant adjustments to the changing environments. Proteolytic activities mediated by various proteases in chloroplast are essential part of this process and critical for maintaining normal chloroplast functions under HT. However, little is known about mechanisms that contribute to adaptation of photosynthetic processes to HT. Our study has shown that a chloroplast-targeted Arabidopsis FtsH11 protease plays an essential and specific role in maintaining thermostability of thylakoids and normal photosynthesis at moderate HT. We hypothesized that FtsH11 homologs recently identified in other plant species might have roles similarly to that of AtFtsH1. Thus, dissecting the underlying mechanisms of FtsH11 in the adaptation mechanisms in chloroplasts to HT stress and other elements involved will aid our effort to produce more agricultural products in less favorable environments. Major conclusions, solutions, achievements - Identified the chloroplast inner envelope membrane localization of FtsH11. - Revealed a specific association of FtsH11 with the a and b subunits of CPN60. - Identified the involvement of ARC6, a protein coordinates chloroplast division machineries in plants, in FtsH11 mediated HT adaptation process in chloroplast. -Reveal possible association of a polyribonucleotide nucleotidyltransferase (cpPNPase), coded by At3G03710, with FtsH11 mediated HT adaptation process in chloroplast. - Mapped 4 additional loci in FtsH11 mediated HT adaptation network in chloroplast. - Demonstrated importance of the proteolytic activity of FtsH11 for thermotolerance, in addition to the ATPase activity. - Demonstrated a conserved role of plant FtsH11 proteases in chloroplast biogenesis and in maintaining structural and functional thermostability of chloroplast at elevated temperatures. Implications, both scientific and agricultural:Three different components interacting with FtsH11 were identified during the course of this study. At present, it is not known whether these proteins are directly involved in FtsH11mediated thermotolerance network in chloroplast and/or how these elements are interrelated. Studies aiming to connect the dot among biological functions of these networks are underway in both labs. Nevertheless, in bacteria where it was first studied, FtsH functions in heat shock response by regulating transcription level of σ32, a heat chock factor regulates HSPsexpression. FtsH also involves in control of biosynthesis of membrane components and quality control of membrane proteins etc. In plants, both Arc 6 and CPN60 identified in this study are essential in chloroplast division and developments as mutation of either one impairs chloroplast division in Arabidopsis. The facts that we have found the specific association of both α and β CPN60 with FtsH11 protein biochemically, the suppression/ enhancement of ftsh11 thermosensitive phenotype by arc6 /pnp allele genetically, implicate inter-connection of these networks via FtsH11 mediated network(s) in regulating the dynamic adaptation processes of chloroplast to temperature increases at transcriptional, translational and post-translational levels. The conserved role of FtsH11 proteases in maintaining thermostability of chloroplast at HT demonstrated here provides a foundation for improving crop photosynthetic performance at high temperatures.
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Ramm-Granberg, Tynan, F. Rocchio, Catharine Copass, Rachel Brunner, and Eric Nelsen. Revised vegetation classification for Mount Rainier, North Cascades, and Olympic national parks: Project summary report. National Park Service, February 2021. http://dx.doi.org/10.36967/nrr-2284511.

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Field crews recently collected more than 10 years of classification and mapping data in support of the North Coast and Cascades Inventory and Monitoring Network (NCCN) vegetation maps of Mount Rainier (MORA), Olympic (OLYM), and North Cascades (NOCA) National Parks. Synthesis and analysis of these 6000+ plots by Washington Natural Heritage Program (WNHP) and Institute for Natural Resources (INR) staff built on the foundation provided by the earlier classification work of Crawford et al. (2009). These analyses provided support for most of the provisional plant associations in Crawford et al. (2009), while also revealing previously undescribed vegetation types that were not represented in the United States National Vegetation Classification (USNVC). Both provisional and undescribed types have since been submitted to the USNVC by WNHP staff through a peer-reviewed process. NCCN plots were combined with statewide forest and wetland plot data from the US Forest Service (USFS) and other sources to create a comprehensive data set for Washington. Analyses incorporated Cluster Analysis, Nonmetric Multidimensional Scaling (NMS), Multi-Response Permutation Procedure (MRPP), and Indicator Species Analysis (ISA) to identify, vet, and describe USNVC group, alliance, and association distinctions. The resulting revised classification contains 321 plant associations in 99 alliances. A total of 54 upland associations were moved through the peer review process and are now part of the USNVC. Of those, 45 were provisional or preliminary types from Crawford et al. (2009), with 9 additional new associations that were originally identified by INR. WNHP also revised the concepts of 34 associations, wrote descriptions for 2 existing associations, eliminated/archived 2 associations, and created 4 new upland alliances. Finally, WNHP created 27 new wetland alliances and revised or clarified an additional 21 as part of this project (not all of those occur in the parks). This report and accompanying vegetation descriptions, keys and synoptic and environmental tables (all products available from the NPS Data Store project reference: https://irma.nps.gov/DataStore/Reference/Profile/2279907) present the fruit of these combined efforts: a comprehensive, up-to-date vegetation classification for the three major national parks of Washington State.
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Phillips, Donald A., Yitzhak Spiegel, and Howard Ferris. Optimizing nematode management by defining natural chemical bases of behavior. United States Department of Agriculture, November 2006. http://dx.doi.org/10.32747/2006.7587234.bard.

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This project was based on the hypothesis that nematodes interacting with plants as either parasites or beneficial saprophytes are attracted to their host by natural products. This concept was supported by numerous observations that parasitic nematodes are attracted to root exudates. Our overall goal was to identify nematode sensory compounds from root exudates and to use that information for reducing nematicide applications. We applied skills of the investigators to achieve three specific objectives: 1) Identify nematode behavioral cues (e.g., attractants or repellents) in root exudates; 2) Identify new natural nematicidal compounds; and 3) Combine a natural attractant and a nematicide into a nematode trap. Because saprophytic nematodes benefit plants by mineralizing organic matter, we sought compounds attractive primarily to parasitic nematodes. The project was constructed on several complementary foundations. First, data from Dr. Spiegel’s lab showed that under aseptic conditions Ditylenchus dipsaci, a parasite on onion, is attracted to certain fractions of onion root exudates. Second, PI Phillips had a sizeable collection of natural plant products he had identified from previous work on Rhizobium-legume interactions, which could be tested “off the shelf”. Third, Dr. Ferris had access to aseptic and natural populations of various saprophytic and parasitic nematodes. The project focused on five nematode species: D.dipsaci, Heterodera avenae, and Tylenchulussemipenetransat ARO, and Meloidogyne javanicand Caenorhabditis elegans at UCD. Ten pure plant compounds, mostly flavonoids, were tested on the various nematode species using six different assay systems. Results obtained with assorted test systems and by various scientists in the same test systems were essentially irreproducible. Many convincing, Many convincing, i.e. statistically significant, results in one system or with one investigator could not be repeated with other assays or different people. A recent report from others found that these compounds, plus another 30, were inactive as attractants in three additional parasitic nematode species (Wuyts et al. Nematology 8:89- 101, 2006). Assays designed to test the hypothesis that several compounds together are required to attract nematodes have thus far failed to find a reproducibly active combination. In contrast to results using pure plant compounds, complex unfractionated exudates from aseptic onion root reproducibly attracted D. dipsaci in both the ARO and UCD labs. Onion root exudate collection, separation into HPLC fractions, assays using D. dipsaci and MS-MS experiments proceeded collaboratively between ARO and UCD without any definitive identification of an active compound. The final active fraction contained two major molecules and traces of several other compounds. In the end, analytical studies were limited by the amount of onion root exudate and the complexity of the purification process. These tests showed that aseptic plant roots release attractant molecules, but whether nematodes influence that release, as insects trigger release of attractants from plants, is unknown. Related experiments showed that the saprophyte C. elegans stimulates its prey, Pseudomonas bacteria, to increase production of 2, 4-diacetylphloroglucinol (DAPG) a compound that promotes amino acid exudation by plant roots. It is thus possible that saprophytic nematodes are attracted primarily to their bacterial or fungal prey and secondarily to effects of those microorganisms on root exudation. These observations offer promising avenues for understanding root-zone interactions, but no direct routes to controlling nematodes in agriculture were evident. Extracts from two plant sources, Chrysanthemum coronarium and Sequoia sempervirens, showed nematicidal activity at ARO and UCD, respectively. Attempts to purify an active compound from S. sempervirens failed, but preliminary results from C. coronarium are judged to form a potential basis for further work at ARO. These results highlight the problems of studying complex movement patterns in sentient organisms like nematodes and the issues associated with natural product isolation from complex mixtures. Those two difficulties combined with complications now associated with obtaining US visas, slowed and ultimately limited progress on this project. As a result, US investigators expended only 65% of the $207,400 originally planned for this project. The Israeli side of the project advanced more directly toward its scientific goals and lists its expenditures in the customary financial report.
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6

Miller, Gad, and Jeffrey F. Harper. Pollen fertility and the role of ROS and Ca signaling in heat stress tolerance. United States Department of Agriculture, January 2013. http://dx.doi.org/10.32747/2013.7598150.bard.

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The long-term goal of this research is to understand how pollen cope with stress, and identify genes that can be manipulated in crop plants to improve reproductive success during heat stress. The specific aims were to: 1) Compare heat stress dependent changes in gene expression between wild type pollen, and mutants in which pollen are heat sensitive (cngc16) or heat tolerant (apx2-1). 2) Compare cngc16 and apx2 mutants for differences in heat-stress triggered changes in ROS, cNMP, and Ca²⁺ transients. 3) Expand a mutant screen for pollen with increased or decreased thermo-tolerance. These aims were designed to provide novel and fundamental advances to our understanding of stress tolerance in pollen reproductive development, and enable research aimed at improving crop plants to be more productive under conditions of heat stress. Background: Each year crop yields are severely impacted by a variety of stress conditions, including heat, cold, drought, hypoxia, and salt. Reproductive development in flowering plants is highly sensitive to hot or cold temperatures, with even a single hot day or cold night sometimes being fatal to reproductive success. In many plants, pollen tube development and fertilization is often the weakest link. Current speculation about global climate change is that most agricultural regions will experience more extreme environmental fluctuations. With the human food supply largely dependent on seeds, it is critical that we consider ways to improve stress tolerance during fertilization. The heat stress response (HSR) has been intensively studied in vegetative tissues, but is poorly understood during reproductive development. A general paradigm is that HS is accompanied by increased production of reactive oxygen species (ROS) and induction of ROS-scavenging enzymes to protect cells from excess oxidative damage. The activation of the HSR has been linked to cytosolic Ca²⁺ signals, and transcriptional and translational responses, including the increased expression of heat shock proteins (HSPs) and antioxidative pathways. The focus of the proposed research was on two mutations, which have been discovered in a collaboration between the Harper and Miller labs, that either increase or decrease reproductive stress tolerance in a model plant, Arabidopsis thaliana (i.e., cngc16--cyclic nucleotide gated channel 16, apx2-1--ascorbate peroxidase 2,). Major conclusions, solutions, achievements. Using RNA-seq technology, the expression profiles of cngc16 and apx2 pollen grains were independently compared to wild type under favourable conditions and following HS. In comparison to a wild type HSR, there were 2,776 differences in the transcriptome response in cngc16 pollen, consistent with a model in which this heat-sensitive mutant fails to enact or maintain a normal wild-type HSR. In a comparison with apx2 pollen, there were 900 differences in the HSR. Some portion of these 900 differences might contribute to an improved HSR in apx2 pollen. Twenty-seven and 42 transcription factor changes, in cngc16 and apx2-1, respectively, were identified that could provide unique contributions to a pollen HSR. While we found that the functional HS-dependent reprogramming of the pollen transcriptome requires specific activity of CNGC16, we identified in apx2 specific activation of flavonol-biosynthesis pathway and auxin signalling that support a role in pollen thermotolerance. Results from this study have identified metabolic pathways and candidate genes of potential use in improving HS tolerance in pollen. Additionally, we developed new FACS-based methodology that can quantify the stress response for individual pollen in a high-throughput fashion. This technology is being adapted for biological screening of crop plant’s pollen to identify novel thermotolerance traits. Implications, both scientific and agricultural. This study has provided a reference data on the pollen HSR from a model plant, and supports a model that the HSR in pollen has many differences compared to vegetative cells. This provides an important foundation for understanding and improving the pollen HSR, and therefor contributes to the long-term goal of improving productivity in crop plants subjected to temperature stress conditions. A specific hypothesis that has emerged from this study is that pollen thermotolerance can be improved by increasing flavonol accumulation before or during a stress response. Efforts to test this hypothesis have been initiated, and if successful have the potential for application with major seed crops such as maize and rice.
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7

DeVivo, Joseph C. Inventories 2.0: A plan for the next generation of NPS natural resource inventories. National Park Service, 2019. http://dx.doi.org/10.36967/2266646.

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This Inventory 2.0 plan identifies IMD’s planned role in each of the ten inventories, and lays out a framework for ensuring the inventories led by IMD result in scientifically credible information for parks resource management, planning, and operations; and also identifies the means by which studies to collect new inventory data will be identified, prioritized, and implemented. Highlights include: IMD plans to lead three of the ten inventories (Species, Vegetation Community Mapping, and Surficial Geology/Soils Mapping), and contribute to the others in partnership with other programs. For the three IMD-led inventories, IMD will develop (or work with the Geologic Resources Division to develop) peer-reviewed inventory science plans that will lay out inventory objectives; and methods for data management, analysis, and integration to ensure that credible and useful inventory data are provided to parks in a timely manner. IMD will phase in implementation of IMD-led inventories during the first five years of program implementation. This will allow IMD to focus near-term efforts on meeting needs identified by the greatest number of parks (Species) while conducting necessary scoping to further refine needs for Vegetation Community Mapping and Surficial Geology/Soils Mapping inventories. During the next two years, IMD inventory efforts will be focused on implementing the Species Inventory, beginning with foundational work in advance of field data collection efforts to be funded in 2020. Additional scoping to identify suitable methods and minimum product specifications for Vegetation Community and Surficial Geology/Soils Mapping will be conducted in 2019-2020. These two new inventories will be phased in based on findings from scoping and progress toward closing out existing (1.0) inventory efforts. All I&M parks will be eligible for IMD funding to support inventories (see Appendix A). Non-I&M parks established before 2000 may be eligible for studies and activities to collect new inventory data pending approval of the project by the IMD Leadership Team. Inventories 2.0 funding cannot be spent to collect new data in parks established in 2000 or later, that are not currently served by an I&M network. Existing data from other sources may still be synthesized and delivered to these parks, however. Inventories 2.0 funding will not be used to fund programs or initiatives already funded or implemented by other programs or agencies. We will endeavor to partner with these entities when possible and appropriate to meet inventory needs identified in this plan, and to ensure IMD-created inventory (and monitoring) data are available to support other programs. Data and other information products resulting from new IMD-funded inventory studies will be managed by IMD rather than third-party repositories. This does not preclude sharing data with third parties or use of third-party tools or data distribution systems. At a minimum IMD commits to make inventory data available to others via the NPS Data Store (https://irma.nps.gov/DataStore/) as well as data and/or map services. To the extent possible, IMD management of inventory data will use the data management infrastructure used for managing monitoring data. This includes a commitment to leverage data, tools, systems, and expertise where it already exists. Because of IMD’s explicit mandate to integrate I&M data with planning, wherever practicable, IMD commits to work with NPS Planning to ensure map and data services are integrated into NPS Atlas projects for each park or other planning tools as they are developed over time.
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8

Synchak, Bohdan. Freedom of choice and freedom of action in the Ukrainian media. Ivan Franko National University of Lviv, February 2022. http://dx.doi.org/10.30970/vjo.2022.51.11400.

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The article talks about the philosophical foundations that characterize the mechanism of internal inducement to action. As an academic, constitutional, and socio-ideological concept, the boundaries of freedom are outlined, which are displayed in the field of modern media space. The term «freedom» is considered as several philosophical concepts that formed the basis of the modern interpretation of this concept. The totality of its meanings is generalized into one that is adapted for the modern system. Parallels are drawn between the interaction of the concept of user freedom with the plane of domestic mass media because despite, the fact that consciousness is knowledge, the incoming information directly affects the individual and collective consciousness. Using the example of the most popular digital platforms, the components of the impact on users and the legal aspect of their implementation are analyzed. When considering the issues of freedom of choice and freedom of action on the Internet, special attention is paid to methods of collecting and processing information, in particular, the limitations and possibilities of digital programs-algorithms of the popular search engine Google. The types of personal information collected by Google about the user are classified and the possible mechanisms of influence on personal choice and access to information on the Internet are characterized. The article analyzes the constitutional guarantees of freedom and the impact of digital technologies on them. Particular attention is paid to ethics, in particular journalistic, which nominally regulates the limits of the humane, permissible, a / moral (unacceptable/acceptable) in the implementation of professional information activities in the media. Thus, the issue of freedom of choice and freedom of action in the plane of domestic mass media is subject to an objective examination of its components, they are analyzed for a proper constitutionally suitable phenomenon, which must be investigated from the point of view of compliance with human rights and freedoms and professional standards within the media.
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9

Jury, William A., and David Russo. Characterization of Field-Scale Solute Transport in Spatially Variable Unsaturated Field Soils. United States Department of Agriculture, January 1994. http://dx.doi.org/10.32747/1994.7568772.bard.

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This report describes activity conducted in several lines of research associated with field-scale water and solute processes. A major effort was put forth developing a stochastic continuum analysis for an important class of problems involving flow of reactive and non reactive chemicals under steady unsaturated flow. The field-scale velocity covariance tensor has been derived from local soil properties and their variability, producing a large-scale description of the medium that embodies all of the local variability in a statistical sense. Special cases of anisotropic medium properties not aligned along the flow direction of spatially variable solute sorption were analysed in detail, revealing a dependence of solute spreading on subtle features of the variability of the medium, such as cross-correlations between sorption and conductivity. A novel method was developed and tested for measuring hydraulic conductivity at the scale of observation through the interpretation of a solute transport outflow curve as a stochastic-convective process. This undertaking provided a host of new K(q) relationships for existing solute experiments and also laid the foundation for future work developing a self-consistent description of flow and transport under these conditions. Numerical codes were developed for calculating K(q) functions for a variety of solute pulse outflow shapes, including lognormal, Fickian, Mobile-Immobile water, and bimodal. Testing of this new approach against conventional methodology was mixed, and agreed most closely when the assumptions of the new method were met. We conclude that this procedure offers a valuable alternative to conventional methods of measuring K(q), particularly when the application of the method is at a scale (e.g. and agricultural field) that is large compared to the common scale at which conventional K(q) devices operate. The same problem was approached from a numerical perspective, by studying the feasibility of inverting a solute outflow signal to yield the hydraulic parameters of the medium that housed the experiment. We found that the inverse problem was solvable under certain conditions, depending on the amount of noise in the signal and the degree of heterogeneity in the medium. A realistic three dimensional model of transient water and solute movement in a heterogeneous medium that contains plant roots was developed and tested. The approach taken was to generate a single realization of this complex flow event, and examine the results to see whether features were present that might be overlooked in less sophisticated model efforts. One such feature revealed is transverse dispersion, which is a critically important component in the development of macrodispersion in the longitudinal direction. The lateral mixing that was observed greatly exceeded that predicted from simpler approaches, suggesting that at least part of the important physics of the mixing process is embedded in the complexity of three dimensional flow. Another important finding was the observation that variability can produce a pseudo-kinetic behavior for solute adsorption, even when the local models used are equilibrium.
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10

Wu, Yingjie, Selim Gunay, and Khalid Mosalam. Hybrid Simulations for the Seismic Evaluation of Resilient Highway Bridge Systems. Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA, November 2020. http://dx.doi.org/10.55461/ytgv8834.

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Bridges often serve as key links in local and national transportation networks. Bridge closures can result in severe costs, not only in the form of repair or replacement, but also in the form of economic losses related to medium- and long-term interruption of businesses and disruption to surrounding communities. In addition, continuous functionality of bridges is very important after any seismic event for emergency response and recovery purposes. Considering the importance of these structures, the associated structural design philosophy is shifting from collapse prevention to maintaining functionality in the aftermath of moderate to strong earthquakes, referred to as “resiliency” in earthquake engineering research. Moreover, the associated construction philosophy is being modernized with the utilization of accelerated bridge construction (ABC) techniques, which strive to reduce the impact of construction on traffic, society, economy and on-site safety. This report presents two bridge systems that target the aforementioned issues. A study that combined numerical and experimental research was undertaken to characterize the seismic performance of these bridge systems. The first part of the study focuses on the structural system-level response of highway bridges that incorporate a class of innovative connecting devices called the “V-connector,”, which can be used to connect two components in a structural system, e.g., the column and the bridge deck, or the column and its foundation. This device, designed by ACII, Inc., results in an isolation surface at the connection plane via a connector rod placed in a V-shaped tube that is embedded into the concrete. Energy dissipation is provided by friction between a special washer located around the V-shaped tube and a top plate. Because of the period elongation due to the isolation layer and the limited amount of force transferred by the relatively flexible connector rod, bridge columns are protected from experiencing damage, thus leading to improved seismic behavior. The V-connector system also facilitates the ABC by allowing on-site assembly of prefabricated structural parts including those of the V-connector. A single-column, two-span highway bridge located in Northern California was used for the proof-of-concept of the proposed V-connector protective system. The V-connector was designed to result in an elastic bridge response based on nonlinear dynamic analyses of the bridge model with the V-connector. Accordingly, a one-third scale V-connector was fabricated based on a set of selected design parameters. A quasi-static cyclic test was first conducted to characterize the force-displacement relationship of the V-connector, followed by a hybrid simulation (HS) test in the longitudinal direction of the bridge to verify the intended linear elastic response of the bridge system. In the HS test, all bridge components were analytically modeled except for the V-connector, which was simulated as the experimental substructure in a specially designed and constructed test setup. Linear elastic bridge response was confirmed according to the HS results. The response of the bridge with the V-connector was compared against that of the as-built bridge without the V-connector, which experienced significant column damage. These results justified the effectiveness of this innovative device. The second part of the study presents the HS test conducted on a one-third scale two-column bridge bent with self-centering columns (broadly defined as “resilient columns” in this study) to reduce (or ultimately eliminate) any residual drifts. The comparison of the HS test with a previously conducted shaking table test on an identical bridge bent is one of the highlights of this study. The concept of resiliency was incorporated in the design of the bridge bent columns characterized by a well-balanced combination of self-centering, rocking, and energy-dissipating mechanisms. This combination is expected to lead to minimum damage and low levels of residual drifts. The ABC is achieved by utilizing precast columns and end members (cap beam and foundation) through an innovative socket connection. In order to conduct the HS test, a new hybrid simulation system (HSS) was developed, utilizing commonly available software and hardware components in most structural laboratories including: a computational platform using Matlab/Simulink [MathWorks 2015], an interface hardware/software platform dSPACE [2017], and MTS controllers and data acquisition (DAQ) system for the utilized actuators and sensors. Proper operation of the HSS was verified using a trial run without the test specimen before the actual HS test. In the conducted HS test, the two-column bridge bent was simulated as the experimental substructure while modeling the horizontal and vertical inertia masses and corresponding mass proportional damping in the computer. The same ground motions from the shaking table test, consisting of one horizontal component and the vertical component, were applied as input excitations to the equations of motion in the HS. Good matching was obtained between the shaking table and the HS test results, demonstrating the appropriateness of the defined governing equations of motion and the employed damping model, in addition to the reliability of the developed HSS with minimum simulation errors. The small residual drifts and the minimum level of structural damage at large peak drift levels demonstrated the superior seismic response of the innovative design of the bridge bent with self-centering columns. The reliability of the developed HS approach motivated performing a follow-up HS study focusing on the transverse direction of the bridge, where the entire two-span bridge deck and its abutments represented the computational substructure, while the two-column bridge bent was the physical substructure. This investigation was effective in shedding light on the system-level performance of the entire bridge system that incorporated innovative bridge bent design beyond what can be achieved via shaking table tests, which are usually limited by large-scale bridge system testing capacities.
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