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The Dark Energy Survey (DES) is a next generation optical survey aimed at understanding the accelerating expansion of the universe using four complementary methods: weak gravitational lensing, galaxy cluster counts, baryon acoustic oscillations, and Type Ia supernovae. To perform the 5000 sq-degree wide field and 30 sq-degree supernova surveys, the DES Collaboration built the Dark Energy Camera (DECam), a 3 square-degree, 570-Megapixel CCD camera that was installed at the prime focus of the Blanco 4-meter telescope at the Cerro Tololo Inter-American Observatory (CTIO). DES started its first observing season on August 31, 2013 and observed for 105 nights through mid-February 2014. This paper describes DES “Year 1” (Y1), the strategy and goals for the first year's data, provides an outline of the operations procedures, lists the efficiency of survey operations and the causes of lost observing time, provides details about the quality of the first year's data, and hints at the “Year 2” plan and outlook.

PreCam, a precursor observational campaign supporting the Dark Energy Survey (DES), is designed to produce a photometric and astrometric catalog of nearly a hundred thousand standard stars within the DES footprint, while the PreCam instrument also serves as a prototype testbed for the Dark Energy Camera (DECam)'s hardware and software. This catalog represents a potential 100-fold increase in Southern Hemisphere photometric standard stars, and therefore will be an important component in the calibration of the Dark Energy Survey. We provide details on the PreCam instrument's design, construction and testing, as well as results from a subset of the 51 nights of PreCam survey observations on the University of Michigan Department of Astronomy's Curtis-Schmidt telescope at Cerro Tololo Inter-American Observatory. We briefly describe the preliminary data processing pipeline that has been developed for PreCam data and the preliminary results of the instrument performance, as well as astrometry and photometry of a sample of stars previously included in other southern sky surveys., Comment: 21 pages, 15 figures, submitted to PASP

Total quantities of urine and feces excreted daily were collected from 12 lactating Holstein dairy cows averaging 567 kg (1250 lb) on fixed feed intake averaging 20 kg (44 lb) of dry matter per day, or 16 kg (36 lb) of dry matter per day per 454 kg (1000 lb) of body weight. Amounts of total and volatile solids, acid detergent lignin, phosphorus in feces, and phosphorus in urine were determined. Cows excreted an average of 44.6 kg (98.1 lb) of raw waste, 6.08 kg (13.1 lb) of total solids in feces, and 0.16 kg (0.3 lb) of fixed solids in feces daily, expressed per 454 kg (1000 lb) of body weight. Total solids of feces represented 36.4% of the daily diet dry matter intake. These values are greater than table values developed by previous researchers and used to design dairy farm facilities. Feces to urine ratio (w/w) ranged from 1.4:1 to 1.9:1. Fecal grab samples (n = 383) from cows on commercial dairies, for which estimated daily intake of feed was available, had greater acid detergent lignin content (16.9 vs. 13.8%) and about 60% more than cows on the total collection trial (4.2 vs. 2.6%), perhaps due to some ingestion of sand on pasture. For all fecal samples fixed solids percentages were much less than table values developed by previous researchers. Differences may be due, in part, to improved genetic potential of cows, because of increased feed intake, climate, or intensive management practices. Our research also confirmed that the quantity of phosphorus (P) excreted in feces was variable, but depended on intake of dietary P.

A series of studies examined the binding characteristics and ontogeny of hepatic growth hormone binding sites in dairy bulls on d 2, 30, 180, and 365 of age. Binding of iodinated recombinant bovine growth hormone ([125I]rbGH) to liver membrane receptors was membrane protein-dependent. Receptors were considered growth hormone-specific, because physiological concentrations of bovine prolactin (bPRL) failed to displace [125I]rbGH from bovine hepatocyte membranes. Only 50% of [125I]rbGH was bound reversibly to hepatic microsomes. Addition of dithiothreitol (DTT) to the receptor-assay buffer increased the binding of [125I]rbGH to hepatic membranes in a time-dependent manner. Moderate concentrations of Ca++ and Mg++ in the receptor-assay buffer had no detectable effects on binding of [125I]rbGH to hepatic microsomes. In growing dairy bulls, specific binding of [125I]rbGH per milligram of membrane protein increased from 1.9 +/- 1.8% at d 2 to 14.1 +/- 1.8% at d 180 and then declined to 5.2 +/- 1.6% at d 365. Likewise, concentration of insulin-like growth factor (IGF)-I in serum was low during the 1st mo of age (d 2, 13.3 +/- 8.8 ng/ml; d 30, 9.7 +/- 8.8 ng/ml), but it became maximal at d 180 (151.0 +/- 8.8 ng/ml). Circulating concentrations of IGF-II increased linearly during the 1st yr of growth. Serum concentrations of GH, triiodothyronine, and thyroxine declined from 39.9 +/- 6.5, 2.7 +/- .2, and 75.4 +/- 4.6 ng/ml at d 2 to 16.5 +/- 6.5, 1.3 +/- .2, and 53.4 +/- 4.6 ng/ml at d 30, respectively, and remained low through 1 yr of age. Insulin concentration in serum did not change significantly with development. Results indicated that increasing concentrations of specific bGH receptors in the bovine liver may play a key role in regulating postnatal growth in cattle.

A short-term treatment with estradiol-17 beta and progesterone induced mammary gland growth and lactogenesis in non-pregnant ewes. These events normally occur during the second half of pregnancy. In order to compare the hormonal environment during the treatment to that during pregnancy, the concentrations of total estrogens (TE), progesterone (P4), glucocorticoids (G) and prolactin (Prl) in the plasma were characterized in non-pregnant, intact ewes induced into lactation with subcutaneous injections of estradiol-17 beta (E2-beta) and P4 for 7 consecutive days (days 1 to 7). Eight non-pregnant, intact, multiparous ewes were divided into two groups (groups I and II, 4 ewes each), according to their milk yields recorded during the previous lactation. All the ewes received the short-term treatment with E2-beta and P4; the ewes of group II were also injected with hydrocortisone acetate (H) and growth hormone (GH) twice daily on days 18 to 20. Blood was collected twice daily for 21 days and milking was initiated 19 days after the first injection of E2-beta and P4. Concentrations of TE, P4, G and Prl were measured in the plasma of ewes in group I but only G and Prl were measured in the plasma of the ewes in group II. Two ewes of group I and one of group II failed to lactate. Mean milk yields (2.5 +/- 0.4 and 6.3 +/- 0.9 kg/34 days) were highest when injections of H and GH were included. Average pretreatment concentrations of plasma TE and P4 were 3.1 +/- 0.8 and 2.1 +/- 0.4 ng/ml, respectively; these increased to 10.2 +/- 1.3 and 5.6 +/- 0.6 ng/ml during the week of the E2-beta and P4 injections. Peak concentrations occurred on days 7 and 6, respectively, and the plasma levels had returned to pretreatment values by days 18 to 20. Concentrations of G in plasma were higher (13.0 +/- 1.0 ng/ml) during E2-beta and P4 injections than during pre- or post-injection (7.4 +/- 1.4 and 8.2 +/- 0.7 ng/ml, respectively). Plasma Prl showed biphasic two to six-fold increases on days 4 and 7 during E2-beta and P4 injections and thereafter declined to lower average daily concentrations on days 10 to 13. Plasma Prl began to increase, and its average concentration was 579 +/- 56 ng/ml by days 18 to 20. These results suggest that the amount of the P4 injections should be increased and that the treatment with E2-beta and P4 should last long enough to insure the induction of an endocrine balance which would correspond more accurately to the hormonal events occurring during the second half of pregnancy in the ewe.