The Role of Sphagnum Fimbriatum in Secondary Succession in a Road-Salt Impacted Bog

Secondary succession of Sphagnum mosses was studied for 7 years along a belt transect in a bog that had been impacted by sodium chloride highway deicing salts. Laboratory studies on Sphagnumfimbriatum Wils., the dominant recolonizing species, were conducted to determine its salt tolerance level and ability to reproduce from spores and fragments across a salt gradient. Vegetative reproduction was also compared with that of four other recolonizing species. Sphagnumfimbriatum represented a high percentage of all recolonizing Sphagnum and generally began growing on low hummocks in quadrats where the salt content of the interstitial peat pore waters had dropped to about 300 mg/L as chloride. This salt concentration was also found to be the basic tolerance limit for mature plants and reproducing spores and fragments. The success of Sphagnum fimbriatum as a pioneer species seems to be associated with its prolific production and probable dispersal of spores, its superior vegetative reproduction, its tolerance of mineralized waters, and its ability to grow on hummocks out of direct contact with mineralized waters

New Records for Sphagnum in Indiana

The Indiana Sphagnum flora is expanded from 10 to 28 species. Sphagnum.henryense, S. recurvum, and S. bartlettianum are more southerly species reaching northern limits while S.centrale, S. papillosum, S. squarrosum, S. teres, S. contortum, S. platyphyllum, S. fallax, S.flexuosum, S. augustifolium, S. pulchrum, S. riparium, S. capillifolium, S. subtile, S. rubellum, S.fuscum, S. girgensohnii, S. russowii, S. fimbriatum, and S. wulfianum are northern species which reach a southern limit in Indiana. One half of the northern species are limited to the three northern counties bordering Lake Michigan, but the occurrence of the other half in an apparently recently colonized abandoned sandstone quarry in the middle of the state suggests that the limiting factor may be habitat more than climate. The most extensive peatland in the state, Pinhook Bog, is briefly characterized

BOTPPI, a New Wittig Salt Used in the Synthesis of 12-(S)-Hydroxy-Eicosatetraenoic Acid [12-(S)-HETE]

An efficient route to (Z)-(8-benzyloxy-8-oxooct-3-en-1-yl)triphenylphosphonium iodide, or BOTPPI, is disclosed, complete with full experimental details, NMR spectra, and HRMS data. BOTPPI serves as a surrogate for (Z)-(8-methoxy-8-oxooct-3-en-1-yl)triphenylphosphonium iodide, or MOTPPI, a Wittig salt previously used in two 12-HETE syntheses. BOTPPI has the advantage over MOTPPI of being derived from a sequence for which every intermediate is UV-active and amenable to large-scale chromatographic purification. A formal asymmetric total synthesis of 12-(S)-HETE is also reported, involving a stereoselective phase-transfer catalyzed (PTC) alkylation in its key step

Формирование активной самостоятельности студентов технических университетов в процессе модульного обучения экономических дисциплин

У статті розглядаються проблеми формування активної самостійності студентів технічних університетів в процесі модульного навчання економічних дисциплін. Автор показує, що ефективність навчання зростає при використанні активних форм і методів – проблемних лекцій, ситуацій, кейсів, ділових ігор, дискусій, наукових досліджень.The paper discusses the issues of development of active independency of technical university students in the process of modular economic training. The paper demonstrates that efficiency of education increases if active forms and methods, such as case studies, situation, business games, discussions, academic research, are used.В статье рассматриваются проблемы формирования активной самостоятельности студентов технических университетов в процессе модульного обучения экономических дисциплин. Автор показывает, что эффективность обучения возрастает при использовании активных форм и методов – проблемных лекций, ситуаций, кейсов, деловых игр, дискуссий, научных исследований

Cross-platform validation of notional baseline architecture models of naval electric ship power systems

To support efforts in assessing the relative merit of alternative power system architectures for future naval combatants, the Electric Ship Research and Development Consortium (ESRDC) has developed notional baseline models for each of the primary candidate architectures currently considered, medium-voltage DC (MVDC), conventional 60 Hz medium-voltage (MVAC), and high-frequency medium-voltage (HFAC). Initial efforts have focused on the development of a consistent set of component models, of which the system models can be comprised, and the basic definition of the system models. The broader objectives of the consortium, however, go beyond the definition of the baseline models. The focus is on the process by which the models are implemented in software and validated, the process by which the performance of the disparate system models are objectively and quantitatively assessed and compared, and, ultimately, the process by which the relative merits of the architectures may be assessed. This paper focuses specifically on cross-platform component validation.Center for Electromechanic

Kinematic analysis of conically scanned environmental properties

A method for determining the velocity of features such as wind. The method preferably includes producing sensor signals and projecting the sensor signals sequentially along lines lying on the surface of a cone. The sensor signals may be in the form of lidar, radar or sonar for example. As the sensor signals are transmitted, the signals contact objects and are backscattered. The backscattered sensor signals are received to determine the location of objects as they pass through the transmission path. The speed and direction the object is moving may be calculated using the backscattered data. The data may be plotted in a two dimensional array with a scan angle on one axis and a scan time on the other axis. The prominent curves that appear in the plot may be analyzed to determine the speed and direction the object is traveling

The Impacts Of Climate Change and Biotic Disturbances On Regeneration Dynamics In Subalpine Forests

Tree regeneration is essential for maintaining forest cover as tree mortality rates continue to increase with warming climate and shifting disturbance regimes. The goal of this research was to examine forest dynamics and potential limitations for tree regeneration under climate warming in Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) forests in Colorado. I used vital rates (e.g., height growth, mortality), quantified from seedling ages and long-term monitoring of trees (1982-2017), to explain the shift from seedling bank dominance by fir to codominance of the forest canopy by spruce and fir. I show that spruce seedlings outcompete the much higher abundances of fir seedlings with faster height grow rates. Higher rates of net population increase (recruitment greater than mortality) and longer residence time of spruce than fir in the forest canopy increases spruce&rsquo;s abundance relative to fir in the forest canopy. Forest cover may shift under climate warming if spruce and fir regeneration is limited by seed availability, unsuitable climate, or severe disturbances. From multiple years of field observations of spruce and fir cone abundance (indicator of seed availability), I found that cone abundance is affected primarily by tree characteristics and stand structure, rather than crowding from neighboring trees. Using models of cone abundance, I interpret how cone abundance may limit spruce and fir tree regeneration following different types of disturbances. To examine the suitable climate conditions for spruce and fir regeneration, I reconstructed germination dates for fir and spruce seedlings from 1940-2010. High abundances of spruce and fir regenerated during years with high moisture availability from above-average snowpack and/or cool and wet summers. Using extensive field sampling from spruce-fir forests affected by three biotic disturbances, I demonstrate that most forests will recover from coincident mortality of spruce and fir from outbreaks of two bark beetle species followed by ungulate herbivory on juvenile trees expected for recovery. The composition of the future forest canopy is, however, uncertain. Collectively, my results highlight that spruce-fir forests have a high capacity to recover from biotic disturbances, but regeneration declines across moisture-limited spruce-fir forests will likely occur as climate warming drives increasing moisture deficits.</p

The Ocean Lifeguard Intervention Continuum: A Cognitive Aid for Surf Lifeguard Education

Ocean lifeguards are constantly engaged in beach risk analysis, required to efficiently evaluate a variety of environmental and other factors quickly in order to triage and prioritize who needs help. Teaching these skills is a challenge for introductory training programs. We sought to improve new lifeguards’ understanding of the interaction of various risk components in the beach environment and aid decision-making related to when a lifeguard should intervene in a situation. We developed a two-part cognitive aid for introductory ocean lifeguard education depicting individual and interacting elements of a beach goer’s risk of drowning or injury and the process by which that risk increases with associated lifeguard interventions on a continuum from low risk and no distress to drowning. This new cognitive aid represented an advancement in the presentation of complex material in introductory training programs for those involved in aquatic rescue