Critically-evaluated propagation rate coefficients in free radical polymerizations .1. Styrene and methyl methacrylate

Critically evaluated rate coefficients and confidence limits, with derived Arrhenius parameters and confidence ellipses, are reported for the propagation rate coefficients of styrene and methyl methacrylate at low conversion in bulk. Data were obtained by pulsed-laser polymerization in several laboratories, and obey the consistency criteria established for this technique. These results provide useful ''benchmarks'' for measurements of propagation rate coefficients by other workers and other techniques

Consistent values of rate parameters in free-radical polymerization systems

To overcome the wide divergence in literature values of kinetic parameters for free radical polymerizations under ostensibly the same conditions, agreed values are given of some fundamental kinetic parameters for simple monomers: propagation rate coefficients and initiator efficiencies for styrene and MMA obtained independently using quite different methods and assumptions. These results and the methodologies employed provide useful "benchmark" tests for other workers and for new techniques. Literature discrepancies are ascribed to subtle mechanistic assumptions made in data interpretation, which are considered in detail. A series of recommendations to assist in overcoming these problems, and to highlight their origins, are presented, with emphasis placed on new techniques including those employing laser photolysis and EPR

Heat and moisture removed by a dairy stable ventilation system during diurnal temperature rhythms.

Missouri Agricultural Experiment Station and the United States Department of Agriculture cooperating.Digitized 2007 AES.Includes bibliographical references (page [27])

The histone H3K4 demethylase JARID1A directly interacts with haematopoietic transcription factor GATA1 in erythroid cells through its second PHD domain

Chromatin remodelling and transcription factors play important roles in lineage commitment and development through control of gene expression. Activation of selected lineage-specific genes and repression of alternative lineage-affiliated genes results in tightly regulated cell differentiation transcriptional programmes. However, the complex functional and physical interplay between transcription factors and chromatin modifying enzymes remains elusive. Recent evidence has implicated histone demethylases in normal haematopoietic differentiation as well as in malignant haematopoiesis. Here we report an interaction between H3K4 demethylase JARID1A and the haematopoietic-specific master transcription proteins SCL and GATA1 in red blood cells. Specifically, we observe a direct physical contact between GATA1 and the second PHD domain of JARID1A. This interaction has potential implications for normal and malignant haematopoiesis

New data and the hard pomeron

New structure-function data are in excellent agreement with the existence of a hard pomeron, with intercept about 1.4. It gives a very economical description of the data. Having fixed 2 parameters from the data for the real-photon cross section $\sigma^{\gamma p}$, we need just 5 further parameters to fit the data for $F_2(x,Q^2)$ with $x\leq 0.001$. The available data range from $Q^2=0.045$ to 35 GeV$^2$. With guesses consistent with dimensional counting for the $x$ dependences of our three separate terms, the fit extends well to larger $x$ and to $Q^2=5000$ GeV$^2$. With no additional parameters, it gives a good description of data for the charm structure function $F_2^c(x,Q^2)$ from $Q^2=0$ to 130 GeV$^2$. The two pomerons also give a good description of both the $W$ and the $t$ dependence of $\gamma p\to J/\psi p$.Comment: 11 pages, plain tex, with 10 figures embedded using epsf. (Spurious figure removed.

Aggregate and emulsion properties of enzymatically-modified octenylsuccinylated waxy starches

Sorghum and maize waxy starches were hydrophobically modified with octenylsuccinic anhydride (OSA) and treated with enzymes before being used to emulsify β-carotene (beta,beta-carotene) and oil in water. Enzyme treatment with β-amylase resulted in emulsions that were broken (separated) earlier and suffered increased degradation of β-carotene, whereas treatment with pullulanase had little effect on emulsions. Combinations of surfactants with high and low hydrodynamic volume (V) indicated that there is a relationship between V and emulsion stability. Degree of branching (DB) had little direct influence on emulsions, though surfactants with the highest DB were poor emulsifiers due to their reduced molecular size. Results indicate that V and branch length (including linear components) are the primary influences on octenylsuccinylated starches forming stable emulsions, due to the increased steric hindrance from short amphiphilic branches, consistent with current understanding of electrosteric stabilization. The success of OSA-modified sorghum starch points to possible new products of interest in arid climates

Moisture vaporization by Jersey and Holstein cows during diurnal temperature cycles as measured with a hygrometric tent.

Missouri Agricultural Experiment Station and the United States Department of Agriculture cooperating.Digitized 2007 AES.Includes bibliographical references (page [19])