Factors affecting protein synthesis in vitro in rabbit reticulocytes

Rabbit reticulocytes in vitro rapidly incorporate labeled amino acids into their proteins. The process is accelerated by the plasma of every mammal investigated and also by extracts of normal erythrocytes, rabbit reticulocytes, liver, spleen, and yeast (1). We have described two sets of stimulating factors: one of these sets consists of certain amino acids (1), the other of fructose-amino acids in liver (2-4). The latter set is ineffective without the addition of iron to the reaction medium. The effect of iron has been referred to in preceding publications (2-5), but without detail. After the necessity of adding iron was recognized, in order to obtain a maximal rate of protein synthesis the reaction mixture was improved further by adding to it certain substances which depend upon added iron for their effect. These increased the effect of plasma. Eventually the total (potential as well as actual) accelerating effects of plasma and liver extract were accounted for by known substances. This led to the devising of a reaction mixture formula in which the amino acid incorporation is about five times as fast as that observed when the cells are incubated in saline

Chromospheric Activity and Jitter Measurements for 2630 Stars on the California Planet Search

We present time series measurements of chromospheric activity for more than 2600 main sequence and subgiant stars on the California Planet Search (CPS) program with spectral types ranging from about F5V to M4V for main sequence stars and from G0IV to about K5IV for subgiants. The large data set of more than 44,000 spectra allows us to identify an empirical baseline floor for chromospheric activity as a function of color and height above the main sequence. We define $\Delta S$ as an excess in emission in the Ca II H\&K lines above the baseline activity floor and define radial velocity jitter as a function of $\Delta S$ and \bv\ for main sequence and subgiant stars. Although the jitter for any individual star can always exceed the baseline level, we find that K dwarfs have the lowest level of jitter. The lack of correlation between observed jitter and chromospheric activity in K dwarfs suggests that the observed jitter is dominated by instrumental or analysis errors and not astrophysical noise sources. Thus, given the long-term precision for the CPS program, radial velocities are not correlated with astrophysical noise for chromospherically quiet K dwarf stars, making these stars particularly well-suited for the highest precision Doppler surveys. Chromospherically quiet F and G dwarfs and subgiants exhibit higher baseline levels of astrophysical jitter than K dwarfs. Despite the fact that the \rms\ in Doppler velocities is correlated with the mean chromospheric activity, it is rare to see one-to-one correlations between the individual time series activity and Doppler measurements, diminishing the prospects for correcting activity-induced velocity variations.Comment: 17 figures, two large tex tables, accepted Ap

Recent Traumatic Disease Claims

Claimants over the years have alleged a causal relation between trauma and almost every conceivable disease. Medicolegal literature abounds with articles concerning the relation between trauma and the more commonly occurring diseases, such as cancer, diabetes, arthritis, bursitis, heart disease, multiple sclerosis, and epilepsy. Numerous books wholly devoted to the relation of trauma and disease, have been written.This article is primarily concerned with cases wherein an allegation is made that a single trauma caused a disease

An AC method of measuring the conductivity of dielectric liquids.

The problem undertaken in this thesis is the presentation of a method of measuring the conductivity of dielectric liquids in which the liquid is used as the parallel tank circuit of a modified Wien-bridge oscillator. The main advantage of this method is that the frequency of the voltage applied to the liquid can be varied by simply varying the oscillator frequency. This allows the selection of a frequency which is best suited to the liquid in regard to polarization and relaxation time. An oscillator was designed, built and used in the laboratory to measure the conductivity of the dielectric liquids -- distilled water, glycerin, and chloroform. The results of these measurements, which are presented in tabular form, agree well with published values for these liquids --Abstract, page ii

Recent Traumatic Disease Claims

Claimants over the years have alleged a causal relation between trauma and almost every conceivable disease. Medicolegal literature abounds with articles concerning the relation between trauma and the more commonly occurring diseases, such as cancer, diabetes, arthritis, bursitis, heart disease, multiple sclerosis, and epilepsy. Numerous books wholly devoted to the relation of trauma and disease, have been written.This article is primarily concerned with cases wherein an allegation is made that a single trauma caused a disease

Rotation periods of exoplanet host stars

The stellar rotation periods of ten exoplanet host stars have been determined using newly analysed Ca II H & K flux records from Mount Wilson Observatory and Stromgren b, y photometric measurements from Tennessee State University's automatic photometric telescopes (APTs) at Fairborn Observatory. Five of the rotation periods have not previously been reported, with that of HD 130322 very strongly detected at Prot = 26.1 \pm 3.5 d. The rotation periods of five other stars have been updated using new data. We use the rotation periods to derive the line-of-sight inclinations of the stellar rotation axes, which may be used to probe theories of planet formation and evolution when combined with the planetary orbital inclination found from other methods. Finally, we estimate the masses of fourteen exoplanets under the assumption that the stellar rotation axis is aligned with the orbital axis. We calculate the mass of HD 92788 b (28 MJ) to be within the low-mass brown dwarf regime and suggest that this object warrants further investigation to confirm its true nature.Comment: Accepted for publication in MNRAS. 15 pages, 11 figure

Distributions and associations of single nucleotide polymorphisms in the leptin gene of Bos taurus and Bos indicus cattle

In recent years, the use of genetic markers has become more and more prevalent in beef breeding programs. This research focused on four previously identified single nucleotide polymorphisms in a leptin gene on chromosome 4 of beef cows. The SNP were E2FB, T945M, UA1, and UA2. Beef cows used in this research were maintained at the Louisiana State University AgCenter Central Research Station. Cows consisted of purebred Bos tauras and Bos indicus cattle as well as crossbreds. The objectives were to estimate genotypic and allelic frequencies for each SNP and to determine the influence of cow breed type, cow age, and SNP genotypes on cow calving rate and date of calving in 2006, cow plasma leptin concentration, body condition score, and pregnancy status in September of 2006, and cow weight change from April to September in 2006. Over all cows, each of the genetic markers showed polymorphism. Allelic frequency for T in these SNP was greater than 0.10. Within cow breed groups the trend for lower or higher frequencies of homozygous genotypes tended to be consistent. Genotypes TT in E2FB, TT in T945M, CC in UA1, and TT in UA2 had lower frequencies. Brahman cows were missing both CT and TT genotypes in UA2 and the UA2‐TT genotype was not present in Braford, Romosinuano F1 and Brahman F1 breed groups. Neither of the genetic marker genotypes influenced variation in plasma leptin level (P \u3e 0.05). Several genetic markers had effects associated with cow traits that were of interest to this research. UA1 genotypes tended (P=0.07) to have an effect on calving rate. UA2 genotypes were associated (P\u3c0.05) with calving date as well as weight loss. Cow breed group influenced (P \u3c 0.05) calving rate, Julian calving date, weight change, and palpation status. Six year and older cows had a larger plasma leptin level and two year old cows had lower body condition scores than other ages of cows. These results indicate that after adjusting for cow breed group and cow age, genetic markers UA1 and UA2 appear to be associated with several reproductive and weight change traits of beef cows