A priori estimates for the motion of a self-gravitating incompressible liquid with free surface boundary

In this paper, we prove a priori estimates in Lagrangian coordinates for the equations of motion of an incompressible, inviscid, self-gravitating fluid with free boundary. The estimates show that on a finite time interval we control five derivatives of the fluid velocity and five and a half derivatives of the coordinates of the moving domain.Comment: To appear in Journal of Hyperbolic Differential Equation

Taxonomische und nomenklatorische Neuigkeiten zur Flora Deutschlands 1

Die Reihe soll zukünftig in unregelmäßiger Folge über Fortschritte in der taxonomischen Forschung und über nomenklatorische Änderungen informieren, sofern Farn- und Samenpflanzen der deutschen Flora betroffen sind. Sie knüpft an die ähnlich strukturierten "Literaturberichte. Floristik und Systematik" in der Zeitschrift "Botanik und Naturschutz in Hessen" an, die von Heft 1 (1987) bis zu Heft 17 (2004) erschienen sind

Contributions to an updated checklist of the German flora (Pteridophyta, Spermatophyta)

Im Rahmen der Vorarbeiten für eine neue Florenliste Deutschlands werden Nomenklaturaspekte bei Achillea collina, Anthriscus, Betula pubescens subsp. carpatica, Camelina microcarpa, Hordelymus, Populus nigra subsp. betulifolia, Silene baccifera sowie bei einigen von Cesati publizierten Unterart- Kombinationen diskutiert. Bei Urtica wird ein alternatives taxonomisches Konzept vorgeschlagen. Die beiden folgenden bisher nicht verfügbaren Kombinationen wurden notwendig: Populus nigra subsp. betulifolia und Urtica subinermis.Details concerning the nomenclature of the taxa Achillea collina, Anthriscus, Betula pubescens subsp. carpatica, Camelina microcarpa, Hordelymus, Populus nigra subsp. betulifolia, Silene baccifera, and some subspecific names published by Cesati respectively are discussed. In the genus Urtica an alternative taxonomical treatment is proposed. Consequently, the following two combinations are implemented: Populus nigra subsp. betulifolia and Urtica subinermis

Taxonomische und nomenklatorische Neuigkeiten zur Flora Deutschlands 2

Im Abschnitt "Taxonomie" werden folgende Sippen besprochen: Festuca ser. Psammophilae, Hierochloë, Orchis ustalata, Sorbus und Viola. Es folgt ein Abschnitt "Molekulare Phylogenetik" mit Hinweisen betreffend Alisma, Betula, Brassicaceae, Coeloglossum/Dactylorhiza, Crataegus/Mespilus, Helichrysum/Pseudognaphalium, Loteae, Plantaginaceae und Salsoleae. Den Abschluss bilden Nachrichten zur Nomenklatur

Buchbesprechungen aus Botanik und Naturschutz in Hessen Bd. 8

Unter anderem folgende Publikationen werden rezensiert: Adler et al.: Exkursionsflora von Österreich. Bestimmungsbuch für alle in Österreich wildwachsenden sowie die wichtigsten kultivierten Gefäßpflanzen (Farnpflanzen und Samenpflanzen) mit Angaben über ihre Ökologie und Verbreitung. Jahn & Schönfelder: Exkursionsflora für Kreta. Wirth: Die Flechten Baden-Württembergs. Adolphi: Neophytische Kultur- und Anbaupflanzen als Kulturflüchtlinge des Rheinlandes. Arbeitsgemeinschaft für Fledermausschutz in Hessen (Herausgeber): Die Fledermäuse Hessens. Sautter: Untersuchungen zur Diasporen- und Samenökologie in bedrohten Pflanzengesellschaften sandiger Böden. Denz: Natürliche Habichtskraut-Traubeneichenwälder bodensaurer Felsstandorte und ihre Vegetationskomplexe im Rheinischen Schiefergebirge und weiteren silikatischen Mittelgebirgen Wißkirchen: Verbreitung und Ökologie von Flußufer-Pioniergesellschaften (Chenopodion rubri) im mittleren und westlichen Europa. Goebel: Die Vegetation der Wiesen, Magerrasen und Rieder im Rhein-Main-Gebiet. Gilbert: Städtische Ökosysteme. Garve: Atlas der gefährdeten Farn- und Blütenpflanzen in Niedersachsen und Bremen

Thermodynamic parameters of bonds in glassy materials from viscosity-temperature relationships

Doremus's model of viscosity assumes that viscous flow in amorphous materials is mediated by broken bonds (configurons). The resulting equation contains four coefficients, which are directly related to the entropies and enthalpies of formation and motion of the configurons. Thus by fitting this viscosity equation to experimental viscosity data these enthalpy and entropy terms can be obtained. The non-linear nature of the equation obtained means that the fitting process is non-trivial. A genetic algorithm based approach has been developed to fit the equation to experimental viscosity data for a number of glassy materials, including SiO2, GeO2, B2O3, anorthite, diopside, xNa2O–(1-x)SiO2, xPbO–(1-x)SiO2, soda-lime-silica glasses, salol, and α-phenyl-o-cresol. Excellent fits of the equation to the viscosity data were obtained over the entire temperature range. The fitting parameters were used to quantitatively determine the enthalpies and entropies of formation and motion of configurons in the analysed systems and the activation energies for flow at high and low temperatures as well as fragility ratios using the Doremus criterion for fragility. A direct anti-correlation between fragility ratio and configuron percolation threshold, which determines the glass transition temperature in the analysed materials, was found

Enhancing wind erosion monitoring and assessment for U.S. rangelands

Wind erosion is a major resource concern for rangeland managers because it can impact soil health, ecosystem structure and function, hydrologic processes, agricultural production, and air quality. Despite its significance, little is known about which landscapes are eroding, by how much, and when. The National Wind Erosion Research Network was established in 2014 to develop tools for monitoring and assessing wind erosion and dust emissions across the United States. The Network, currently consisting of 13 sites, creates opportunities to enhance existing rangeland soil, vegetation, and air quality monitoring programs. Decision-support tools developed by the Network will improve the prediction and management of wind erosion across rangeland ecosystems. © 2017 The Author(s)The Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information

Impacts of increasing anthropogenic soluble iron and nitrogen deposition on ocean biogeochemistry

Author Posting. © American Geophysical Union, 2009. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Global Biogeochemical Cycles 23 (2009): GB3016, doi:10.1029/2008GB003440.We present results from transient sensitivity studies with the Biogeochemical Elemental Cycling (BEC) ocean model to increasing anthropogenic atmospheric inorganic nitrogen (N) and soluble iron (Fe) deposition over the industrial era. Elevated N deposition results from fossil fuel combustion and agriculture, and elevated soluble Fe deposition results from increased atmospheric processing in the presence of anthropogenic pollutants and soluble Fe from combustion sources. Simulations with increasing Fe and increasing Fe and N inputs raised simulated marine nitrogen fixation, with the majority of the increase in the subtropical North and South Pacific, and raised primary production and export in the high-nutrient low-chlorophyll (HNLC) regions. Increasing N inputs alone elevated small phytoplankton and diatom production, resulting in increased phosphorus (P) and Fe limitation for diazotrophs, hence reducing nitrogen fixation (∼6%). Globally, the simulated primary production, sinking particulate organic carbon (POC) export. and atmospheric CO2 uptake were highest under combined increase in Fe and N inputs compared to preindustrial control. Our results suggest that increasing combustion iron sources and aerosol Fe solubility along with atmospheric anthropogenic nitrogen deposition are perturbing marine biogeochemical cycling and could partially explain the observed trend toward increased P limitation at station ALOHA in the subtropical North Pacific. Excess inorganic nitrogen ([NO3 −] + [NH4 +] − 16[PO4 3−]) distributions may offer useful insights for understanding changing ocean circulation and biogeochemistry.This work was supported by funding from NSF grant OCE-0452972 to J. K. Moore and C. S. Zender. Computations were supported by the Earth System Modeling Facility at UCI (NSFATMO321380) and by the Climate Simulation Laboratory at National Center for Atmospheric Research. The National Center for Atmospheric Research is sponsored by the U.S. National Science Foundation. N.M. would like to acknowledge the assistance of NSF– Carbon and Water (ATM-0628472), and N.M., S.D., and C.L. would like to acknowledge the assistance of NASA-IDS (NNX07AL80G)

Impact of Anthropogenic Combustion Emissions on The Fractional Solubility of Aeroosol Iron: Evidence From The Sargasso Sea

We report empirical estimates of the fractional solubility of aerosol iron over the Sargasso Sea during periods characterized by high concentrations of Saharan dust (summer 2003) and by low concentrations of aerosols in North American/maritime North Atlantic air masses (spring 2004 and early summer 2004). We observed a strong inverse relationship between the operational solubility of aerosol iron (defined using a flow-through deionized-water leaching protocol) and the total concentration of aerosol iron, whereby the operational solubility of aerosol iron was elevated when total aerosol iron loadings were low. This relationship is consistent with source-dependent differences in the solubility characteristics of our aerosol samples and can be described by a simple mixing model, wherein bulk aerosols represent a conservative mixture of two air mass end-members that carry different aerosol types: Saharan air,\u27\u27 which contains a relatively high loading of aerosol iron (27.8 nmol Fe m-3) that has a low fractional solubility (0.44%), and North American air,\u27\u27 which contains a relatively low concentration of aerosol iron (0.5 nmol Fe m-3) that has a high fractional solubility (19%). Historical data for aerosols collected on Bermuda indicate that the low iron loadings associated with North American air masses are typically accompanied by elevated V/Al, Fe/Al, and V/Mn mass ratios in the bulk aerosol, relative to Saharan dust, which are indicative of anthropogenic fuel-combustion products. The identification of similar compositional trends in our Sargasso Sea aerosol samples leads us to suggest that the elevated solubility of iron in the aerosols associated with North American air masses reflects the presence of anthropogenic combustion products, which contain iron that is readily soluble relative to iron in Saharan soil dust. We thus propose that the source-dependent composition of aerosol particles (specifically, the relative proportion of anthropogenic combustion products) is a primary determinant for the fractional solubility of aerosol iron over the Sargasso Sea. This hypothesis implies that anthropogenic combustion emissions could play a significant role in determining the atmospheric input of soluble iron to the surface ocean