Dairy and hog farming in northeastern Iowa

On Northeastern Iowa dairy and hog farms, highest returns were obtained where the number of milk cows equaled litters of pigs. This meant about 6 pounds of hogs were produced to each pound of butterfat. Where hog production was less, returns were lower. The butterfat-hog price ratio, during the years of the study, favored hogs, with 1 pound butterfat worth only 3.5 pounds of hogs. Generally, the strictly dairy herds were more profitable than the dual-purpose herds, even though butterfat prices were unfavorable in comparison to beef, during the period studied. Income from beef in the dual-purpose herds was not enough to offset the lower sales of butterfat. The dairy herds, with 16.6 cows, averaged 229 pounds butterfat sold or used in the household, and 493 pounds beef per cow, while the dual-purpose herds, with 14.1 cows, averaged 162 pounds butterfat output and 711 pounds beef per cow

K0 form factor and charge radius in a covariant Salpeter model

The electromagnetic form factor for the $K^0$ is calculated in a covariant formulation of the Salpeter equation for $q\bar q$ - bound states, which has been presented recently for the mass spectrum, decay properties and form factors of the light pseudoscalar and vector mesons. The $K^0$ charge radius dependence on the difference between strange and down constituent quark mass is discussed.Comment: 5 pages including 3 uuencoded figures, RevTe

An economic study of the dairy enterprise in northeastern Iowa

In a study of 51 dairy and dual-purpose herds in 1935 and ] 936 it was found that the average value per head of the milk cows was $66 in the high producing dairy herds, compared to$49 in the low producing ones; while investment in buildings and fences was $120 per cow in the high as compared to$90 in the low producing herds. Investment per pound of butterfat produced, however , was lower with the higher producing and more valuable cows. The cows in the higher producing herds were fed more heavily and received better balanced rations; the total amount of concentrates amounting to approximately 2,300 pounds in the high and 1,200 in the low producing herds, while total value of all feeds plus pasture amounted to $72, compared to$50. When expressed per pound of butterfat, however, the values of feed and pasture were but little different between the high and low producing herds. In fact, the advantage was slightly with the high producing herds. There was a wide variation in amount of feed fed per cow, which was only partly related to the production per cow. The cows receiving the most feed generally produced more butterfat but not necessarily in proportion to the difference in amount of feed. Consequently, the cows receiving the most feed did not give the highest return per $100 of feed fed

Characterization of Knots and Links Arising From Site-specific Recombination on Twist Knots

We develop a model characterizing all possible knots and links arising from recombination starting with a twist knot substrate, extending previous work of Buck and Flapan. We show that all knot or link products fall into three well-understood families of knots and links, and prove that given a positive integer $n$, the number of product knots and links with minimal crossing number equal to $n$ grows proportionally to $n^5$. In the (common) case of twist knot substrates whose products have minimal crossing number one more than the substrate, we prove that the types of products are tightly prescribed. Finally, we give two simple examples to illustrate how this model can help determine previously uncharacterized experimental data.Comment: 32 pages, 7 tables, 27 figures, revised: figures re-arranged, and minor corrections. To appear in Journal of Physics

State-to-State Differential and Relative Integral Cross Sections for Rotationally Inelastic Scattering of H2O by Hydrogen

State-to-state differential cross sections (DCSs) for rotationally inelastic scattering of H2O by H2 have been measured at 71.2 meV (574 cm-1) and 44.8 meV (361 cm-1) collision energy using crossed molecular beams combined with velocity map imaging. A molecular beam containing variable compositions of the (J = 0, 1, 2) rotational states of hydrogen collides with a molecular beam of argon seeded with water vapor that is cooled by supersonic expansion to its lowest para or ortho rotational levels (JKaKc= 000 and 101, respectively). Angular speed distributions of fully specified rotationally excited final states are obtained using velocity map imaging. Relative integral cross sections are obtained by integrating the DCSs taken with the same experimental conditions. Experimental state-specific DCSs are compared with predictions from fully quantum scattering calculations on the most complete H2O-H2 potential energy surface. Comparison of relative total cross sections and state-specific DCSs show excellent agreement with theory in almost all detailsComment: 46 page

Isomorphic classical molecular dynamics model for an excess electron in a supercritical fluid

Ring polymer molecular dynamics (RPMD) is used to directly simulate the dynamics of an excess electron in a supercritical fluid over a broad range of densities. The accuracy of the RPMD model is tested against numerically exact path integral statistics through the use of analytical continuation techniques. At low fluid densities, the RPMD model substantially underestimates the contribution of delocalized states to the dynamics of the excess electron. However, with increasing solvent density, the RPMD model improves, nearly satisfying analytical continuation constraints at densities approaching those of typical liquids. In the high density regime, quantum dispersion substantially decreases the self-diffusion of the solvated electron. In this regime where the dynamics of the electron is strongly coupled to the dynamics of the atoms in the fluid, trajectories that can reveal diffusive motion of the electron are long in comparison to $\beta\hbar$.Comment: 24 pages, 4 figure