Exciton-polariton emission from organic semiconductor optical waveguides

We photo-excite slab polymer waveguides doped with J-aggregating dye molecules and measure the leaky emission from strongly coupled waveguide exciton polariton modes at room temperature. We show that the momentum of the waveguide exciton polaritons can be controlled by modifying the thickness of the excitonic waveguide. Non-resonantly pumped excitons in the slab excitonic waveguide decay into transverse electric and transverse magnetic strongly coupled exciton waveguide modes with radial symmetry. These leak to cones of light with radial and azimuthal polarizations

Grasses and other forage plants

About seventy-live kinds of grasses and other forage plants were sown last spring. A considerable number of these were in one-eighth-acre plots, with a thin seeding of rye for protection. The rye proved to be the winter, instead of the spring variety, as was intended, and it grew so rank as to cover the ground and greatly injure the grasses. It was cut and removed July 7, but the weather following was so hot and dry that some of the kinds failed to recover. In addition to this, a severe attack of chinch bugs occurred in the* latter part of July and nearly destroyed many of the other kinds. Only the true grasses were attacked. The coarser kinds of these, such as Johnson grass, sorghum, teosinte, and the pearl and German millets, suffered least

The work in crossing

To obtain improved varieties of fruits which shall be hardy in Iowa, several thousand successful crosses were made during the past season, mostly upon apples. About one thousand seeds of these crosses, representing nearly fifty varieties, are now preserved in damp sand to be planted next spring. The crosses were mainly of the best American winter apples upon Russian varieties growing at the College. In this work I was aided by the Director’s assistant, Mr. John Craig, and by the following students of the Agricultural College: Mr. F. W. Mally, Mr. J. G. Abraham, Mr. E. A. Sheafe, Mr. Albert McClelland, and Mr. Fred L. Lightner. The selection of the varieties to be crossed was made by the Director and Prof. J. L. Budd. Thanks are due to G. B. Brackett, Denmark, Iowa, N. K. Fluke, Davenport, Iowa, John Saul, Washington D. C., O. R. L. Crozier of Ann Arbor, Michigan, and others, for pollen which they kindly furnished. It is not expected that all the crossed varieties will prove worthy of propagation, but it is believed that a much larger percentage will possess the desired qualities than with chance seedlings. The young trees will be carefully studied, and those found sufficiently hardy and vigorous will be grafted on older stocks to bring them into bearing at an early date

Some injurious fungi

In treating of the following injurious fungi only such facts in regard to their manner of growth are mentioned as is necessary to enable one to apply intelligently the given remedies. A few preliminary remarks therefore concerning fungi as a class will be useful. First, fungi are true plants which originate from spores, often of more than one kind, which answer the purpose of seeds, but which are much simpler in structure. Where no spores are present therefore no fungus or fungus disease can appear, any more than weeds can grow where no seeds have been allowed to ripen. Fungi however produce spores eyen more abundantly than weeds produce seeds, and there is hardly a locality in which fungus spores of some kind are not present. Many fungi however are limited to particular localities, and spread to other regions only when the spores are accidentally introduced, or when the plants upon which they live are introduced for cultivation. Thus the grape rot, which is common through the Eastern States, is still unknown in many parts of the country, and it has but recently been accidentally introduced from this country into France, where it threatened, until checked by artificial remedies, to seriously interfere with grape culture in that country. Many similar examples could be given

Preliminary report on two Triassic dicynodonts from Zambia.

Main articleThe purpose of this communication is to establish the presence of a species of Stahleckeriid, hitherto known only from India, in the Zambian Triassic N'tawere Formation and to establish the new specific name of the Kannemeyeria specimen also recorded from the same locality. The skulls and some post-cranial material of these two dicynodonts were collected by Mr. James Kitching from the Luangwa Valley, Zambia in 1961. The material comes from Locality 16, of the Lower Fossiliferous Horizon in the N'tawere Formation. One large skull has been assigned to genus and species Rechnisaurus cristarhynchus Roy Chowdhury, 1970. The other skull and the postcranial material has been named Kannemeyeria latirostris sp. nov. One other specimen has been described from this locality, Diademodon rhodesiensis (Brink 1963), which marks it as being of near Cynognathus-zone age.Non

Using Preconditioning Programs as a Management Tool for Value Added Calves

This publication discusses using preconditioning programs as a management tool for value added calves

Fat transforms ascorbic acid from inhibiting to promoting acid-catalysed N-nitrosation

<b>Background</b>: The major potential site of acid nitrosation is the proximal stomach, an anatomical site prone to a rising incidence of metaplasia and adenocarcinoma. Nitrite, a pre-carcinogen present in saliva, can be converted to nitrosating species and N-nitroso compounds by acidification at low gastric pH in the presence of thiocyanate. <b>Aims</b>: To assess the effect of lipid and ascorbic acid on the nitrosative chemistry under conditions simulating the human proximal stomach. <b>Methods</b>: The nitrosative chemistry was modelled in vitro by measuring the nitrosation of four secondary amines under conditions simulating the proximal stomach. The N-nitrosamines formed were measured by gas chromatography–ion-trap tandem mass spectrometry, while nitric oxide and oxygen levels were measured amperometrically. <b>Results</b>: In absence of lipid, nitrosative stress was inhibited by ascorbic acid through conversion of nitrosating species to nitric oxide. Addition of ascorbic acid reduced the amount of N-nitrosodimethylamine formed by fivefold, N-nitrosomorpholine by .1000-fold, and totally prevented the formation of N-nitrosodiethylamine and N-nitrosopiperidine. In contrast, when 10% lipid was present, ascorbic acid increased the amount of Nnitrosodimethylamine, N-nitrosodiethylamine and N-nitrosopiperidine formed by approximately 8-, 60- and 140-fold, respectively, compared with absence of ascorbic acid. <b>Conclusion</b>: The presence of lipid converts ascorbic acid from inhibiting to promoting acid nitrosation. This may be explained by nitric oxide, formed by ascorbic acid in the aqueous phase, being able to regenerate nitrosating species by reacting with oxygen in the lipid phase

Bridging the Gap: Engaging Business Sophomores to Ensure Information Literacy Competency

This project showcases a two-week series of assignments that are designed to illustrate the value of information literacy skills to undergraduate sophomore business students. We demonstrate how the project integrates with our business curricula and show how leveraging the expertise of librarians ultimately improves the quality of education for our students