Profile Characteristics of Some Forest-Formed Soils Derived from Iowan Till

Three profiles were collected in Bremer and Floyd counties to represent the proposed Coggon series; detailed field and laboratory studies were conducted on these profiles. The Coggon soils have developed under forest vegetation from a two-story parent material consisting of a silty mantle-pebble band-glacial till sequence. Being formed from Iowan-age glacial till, the Coggon profiles exhibit an amount of development that is low compared to other Gray-Brown Podzolic soils of Iowa. Coarser parent material might possibly explain why Coggon is less developed than the Weller soils, which are formed from presumably younger, loessial parent material. On the other hand, the lack of development in Coggon could be explained by its youth if one considers the possibility that the present geomorphic surface of the Iowan till represents a rather young pedi-sedimented surface which is more recent than the last glaciation

Characteristics of the Floyd and Some Related Soils in Floyd and Bremer Counties, Iowa

This study deals with imperfectly and poorly drained soils generally considered to have developed under prairie from a parent material consisting of a sandy-silt mantle overlying Iowan glacial loam till. Three Floyd profiles, two profiles of the proposed Tripoli series (Floyd, poorly drained variant), and one Clyde profile were studied in the field and in the laboratory. Results indicate that the Tripoli soils should be separated from the Floyd and mapped as a separate series. The present concepts of the Floyd series as a minimal Brunizem and the Tripoli as a minimal Wiesenboden are substantiated by field studies and laboratory data

First principles investigations of the electronic, magnetic and chemical bonding properties of CeTSn (T=Rh,Ru)

The electronic structures of CeRhSn and CeRuSn are self-consistently calculated within density functional theory using the local spin density approximation for exchange and correlation. In agreement with experimental findings, the analyses of the electronic structures and of the chemical bonding properties point to the absence of magnetization within the mixed valent Rh based system while a finite magnetic moment is observed for trivalent cerium within the Ru-based stannide, which contains both trivalent and intermediate valent Ce.Comment: 6 pages, 7 figures, for more information see http://www.physik.uni-augsburg.de/~eyert

Causes of Differences in Soil Series of the Missouri River Bottomlands of Monona County

The current soil survey of Monona County has revealed many differences in the alluvial deposits occurring in the Missouri River bottomlands. As a consequence the soils developed from these different deposits show numerous dissimilarities. It is the purpose of this paper to describe and explain the causes of the differences encountered. The principal factors in soil formation are climate, organisms, topography, parent material and time. In the Missouri River bottomlands of Monona County it can be assumed that climate and organisms are not important causes of soil differences. In general, differences in topography are closely related to differences in parent material. Thus parent material or time of deposition or both, must be the principal cause or causes of soil differences. The soils found on the Missouri River bottomlands are, for the most part, formed from alluvial materials. Some coarser alluvium may have been resorted by wind action subsequent to deposition but areas showing evidence of wind action are not extensive. The principal source of alluvium is the Missouri River; next, the tributary rivers and streams; and, of least importance, the steep bluffs that form the sides of the valley

Properties of Two Profiles of the Hayden Series

The soils formed under forest vegetation from Late Wisconsin glacial till in Northcentral Iowa were classified, according to the summary by Brown (1936), chiefly with the Conover series. In the soil survey of Story County, similar soils were classified with the Ames and Lindley series according to Meldrum, Perfect, and Mogen (1941). The Ames series is a Planosol formed under forest vegetation and occurs on nearly level to slightly level areas. As the Lindley soils occur principally in the Kansan till area, they include soils with ferretto-like profiles. Thus, it seemed desirable to introduce a new series for most of those soils classified as Lindley in the Story County soil survey and for the sloping soils mainly classified as Conover in Boone County. Therefore, the Hayden series, originally established in Minnesota as the Gray Brown Podzolic correlative of the Clarion series, a Brunizem, has been introduced into Iowa as has been discussed by Simonson, Riecken, and Smith (1952). This paper is a report of a study of two Hayden profiles, with a discussion of its relationship to the Clarion series and also to some other Gray Brown Padzolic series

Estimated crop yields on Iowa soils

Everyone interested in agriculture is concerned, to some degree, with estimating crop yields. Estimated yields are a basis for appraising farmland and frequently are used for establishing rental arrangements and determining farm sale and loan values. They also are used in planning the farm business and in developing various agricultural programs.https://lib.dr.iastate.edu/specialreports/1022/thumbnail.jp

Searching for hexagonal analogues of the half-metallic half-Heusler XYZ compounds

The XYZ half-Heusler crystal structure can conveniently be described as a tetrahedral zinc blende YZ structure which is stuffed by a slightly ionic X species. This description is well suited to understand the electronic structure of semiconducting 8-electron compounds such as LiAlSi (formulated Li$^+$[AlSi]$^-$) or semiconducting 18-electron compounds such as TiCoSb (formulated Ti$^{4+}$[CoSb]$^{4-}$). The basis for this is that [AlSi]$^-$ (with the same electron count as Si$_2$) and [CoSb]$^{4-}$ (the same electron count as GaSb), are both structurally and electronically, zinc-blende semiconductors. The electronic structure of half-metallic ferromagnets in this structure type can then be described as semiconductors with stuffing magnetic ions which have a local moment: For example, 22 electron MnNiSb can be written Mn$^{3+}$[NiSb]$^{3-}$. The tendency in the 18 electron compound for a semiconducting gap -- believed to arise from strong covalency -- is carried over in MnNiSb to a tendency for a gap in one spin direction. Here we similarly propose the systematic examination of 18-electron hexagonal compounds for semiconducting gaps; these would be the "stuffed wurtzite" analogues of the "stuffed zinc blende" half-Heusler compounds. These semiconductors could then serve as the basis for possibly new families of half-metallic compounds, attained through appropriate replacement of non-magnetic ions by magnetic ones. These semiconductors and semimetals with tunable charge carrier concentrations could also be interesting in the context of magnetoresistive and thermoelectric materials.Comment: 11 pages, 6 figures, of which 4 are colou

Profile Properties of Some Loess-Derived Brunizem Soils of Southeastern Iowa

Brown (1936, p 18) summarized the information up to 1936 on the geography and classification of the prairie loess-derived soils of southeastern Iowa. The Tama and Grundy were the major series recognized. Field studies since 1942 indicated there was a need to revise the concept of these series. The present paper presents some data on selected profiles formerly classed with these series

Collagen type XVIII/endostatin is differentially expressed in primary and metastatic colorectal cancers and ovarian carcinomas

Collagen type XVIII (C18) is a nonfibrillar collagen of basement membranes. Its C-terminal fragment, endostatin, has been identified as an inhibitor of angiogenesis. C18 is predominantly expressed by hepatocytes of normal, cirrhotic and neoplastic liver. We compared the patterns of C18 RNA-expression in colonic adenocarcinoma metastases, which represent the most frequently occurring liver tumours, to normal colon mucosa, to primary colon cancers and to ovarian cancers which are often morphologically similar to colonic cancer or metastasis. Two C18-specific RNA-probes were generated to perform in situ hybridization combined with immunohistochemistry for cytokeratin, vimentin and the endothelial marker CD31, in order to characterize the C18-expressing cells. C18/endostatin protein was localized by immunohistology. In colorectal carcinomas and their liver metastases high levels of C18 transcripts were observed in endothelial cells and fibroblasts/myofibroblasts, whereas C18 RNA was virtually absent from carcinoma cells. Ovarian carcinomas displayed high C18 RNA expression both in carcinoma and stromal cells, indicating that induction of C18 transcription in tumour stromal cells is independent of the ability of carcinoma cells to express C18. While the role of tumour cell derived C18 in cancer growth regulation remains unknown, stimulation of proteolysis of the locally strongly expressed C18 to endostatin could offer an attractive approach for a targeted antineoplastic therapy. © 2001 Cancer Research Campaign   http://www.bjcancer.co

Measuring The Evolutionary Rate Of Cooling Of ZZ Ceti

We have finally measured the evolutionary rate of cooling of the pulsating hydrogen atmosphere (DA) white dwarf ZZ Ceti (Ross 548), as reflected by the drift rate of the 213.13260694 s period. Using 41 yr of time-series photometry from 1970 November to 2012 January, we determine the rate of change of this period with time to be dP/dt = (5.2 +/- 1.4) x 10(-15) s s(-1) employing the O - C method and (5.45 +/- 0.79) x 10(-15) s s(-1) using a direct nonlinear least squares fit to the entire lightcurve. We adopt the dP/dt obtained from the nonlinear least squares program as our final determination, but augment the corresponding uncertainty to a more realistic value, ultimately arriving at the measurement of dP/dt = (5.5 +/- 1.0) x 10(-15) s s(-1). After correcting for proper motion, the evolutionary rate of cooling of ZZ Ceti is computed to be (3.3 +/- 1.1) x 10(-15) s s(-1). This value is consistent within uncertainties with the measurement of (4.19 +/- 0.73) x 10(-15) s s(-1) for another similar pulsating DA white dwarf, G 117-B15A. Measuring the cooling rate of ZZ Ceti helps us refine our stellar structure and evolutionary models, as cooling depends mainly on the core composition and stellar mass. Calibrating white dwarf cooling curves with this measurement will reduce the theoretical uncertainties involved in white dwarf cosmochronometry. Should the 213.13 s period be trapped in the hydrogen envelope, then our determination of its drift rate compared to the expected evolutionary rate suggests an additional source of stellar cooling. Attributing the excess cooling to the emission of axions imposes a constraint on the mass of the hypothetical axion particle.NSF AST-1008734, AST-0909107Norman Hackerman Advanced Research Program 003658-0252-2009Astronom