Gravitational Radiation from Compact Binary Pulsars

An outstanding question in modern Physics is whether general relativity (GR) is a complete description of gravity among bodies at macroscopic scales. Currently, the best experiments supporting this hypothesis are based on high-precision timing of radio pulsars. This chapter reviews recent advances in the field with a focus on compact binary millisecond pulsars with white-dwarf (WD) companions. These systems - if modeled properly - provide an unparalleled test ground for physically motivated alternatives to GR that deviate significantly in the strong-field regime. Recent improvements in observational techniques and advances in our understanding of WD interiors have enabled a series of precise mass measurements in such systems. These masses, combined with high-precision radio timing of the pulsars, result to stringent constraints on the radiative properties of gravity, qualitatively very different from what was available in the past.Comment: Short review chapter to appear in "Gravitational Wave Astrophysics" by Springer-Verlag, edited by Carlos F. Sopuerta; v3: a few major corrections and updated references. Comments are welcome

Horizontal Branch Stars: The Interplay between Observations and Theory, and Insights into the Formation of the Galaxy

We review HB stars in a broad astrophysical context, including both variable and non-variable stars. A reassessment of the Oosterhoff dichotomy is presented, which provides unprecedented detail regarding its origin and systematics. We show that the Oosterhoff dichotomy and the distribution of globular clusters (GCs) in the HB morphology-metallicity plane both exclude, with high statistical significance, the possibility that the Galactic halo may have formed from the accretion of dwarf galaxies resembling present-day Milky Way satellites such as Fornax, Sagittarius, and the LMC. A rediscussion of the second-parameter problem is presented. A technique is proposed to estimate the HB types of extragalactic GCs on the basis of integrated far-UV photometry. The relationship between the absolute V magnitude of the HB at the RR Lyrae level and metallicity, as obtained on the basis of trigonometric parallax measurements for the star RR Lyrae, is also revisited, giving a distance modulus to the LMC of (m-M)_0 = 18.44+/-0.11. RR Lyrae period change rates are studied. Finally, the conductive opacities used in evolutionary calculations of low-mass stars are investigated. [ABRIDGED]Comment: 56 pages, 22 figures. Invited review, to appear in Astrophysics and Space Scienc

Serodiagnosis of enzootic pneumonia

Enzootic pneumonia is an economically significant disease in pig herds. As no serological tests were available in Queensland an efficient test was required for its identification in minimal disease herd

Serodiagnosis of enzootic pneumonia

Enzootic pneumonia is an economically significant disease in pig herds. As no serological tests were available in Queensland an efficient test was required for its identification in minimal disease herd

Early weaning in Northern Great Plains beef cattle production systems: III. Steer weaning, finishing and carcass characteristics

Studies were conducted to evaluate the effect of early weaning steer calves on BW gain, feedlot performance, and carcass characteristics in two herds located in the Northern Great Plains, USA. Steer calves from predominantly Angus x Hereford dams were stratified within damage and calving date (Fort Keogh Livestock and Range Research Laboratory (LARRL), Miles City, MT, USA; n=354)and randomly assigned to one of three weaning treatments. In addition, steer calves from Angus and Angus x Simmental dams (n=200; Judith Gap (JG), MT, USA) were stratified within breed group by age, calving date, and AI sire. Steer calves either remained with their dams until normal weaning (NW) at approximately 213-d of age or were early weaned at approximately 80-d of age on to one of two early weaning (EW) diets. Steer calves assigned to EW treatments received one of the following diets: (1)17.5% CP (69% RDP and 7.53 MJ/kg NEm); or (2)17.5% CP (57% RDP and 7.69MJ/kg NEm). At time of normal weaning all LARRL steers were gathered and brought into pens at LARRL and held for 22 (2005) or 28-d (2006) before being sold to a commercial feedlot. Sire-identified steers from JG were sent to the University of Illinois for a finishing trial following a 28-d holding period. Steers that were EW were heavier (PPP=0.79) regardless of weaning treatment whereas sire-identified JG steers that received EW treatment were harvested at a younger age (PP=0.05; upper 2/3 choice or better) than NW treated steers (

The effect of feed supplementation on the onset of puberty in Brazilian dairy heifers Efeito da suplementação alimentar no início da puberdade em novilhas brasileiras

Most Brazilian dairy production is conducted by small holders whose general management skills and feeding programs are often deficient. One common problem directly attributed to underfeeding is that heifers rarely reach sexual maturity before 15 months of age. Groups of growing heifers were treated to detect the effects of protein supplementation and antihelmintic treatment on sexual maturity. The first ovulation occurred at 513 &plusmn; 44 and 573 &plusmn; 36 days (P<.01) in supplemented and control groups, respectively. Liveweight gains from start of the trial to the first ovulation were 378 &plusmn;.02 and 331 &plusmn;.04 g for suplemented (S) and control (C) groups. Only 52.17 % of heifers in C group (11 of 23) but 95.65 % in S group (22 of 23) reached sexual maturity before the age of 18 mo (P< .01). Animals with anthelmintic treatment had better growth performance than the controls.<br>A maior parte da produção de leite no Brasil é fornecida por pequenos proprietários cujos programas de alimentação e manejo são freqüentemente deficientes. Um problema freqüente diretamente relacionado com a subnutrição é que raramente uma novilha atinge a maturidade sexual antes dos 15 meses de idade. Grupos de novilhas foram tratadas para detectar os efeitos da suplementação proteica e tratamento antihelmíntico sobre a maturidade sexual. A primeira ovulação ocorreu 513 &plusmn; 44 e 573 &plusmn; 36 dias (P < 0,01) nos grupos suplementados e controle, respectivamente. Os ganhos de peso vivo do início do ensaio à primeira ovulação foram 378 &plusmn; 0,02 e 331 &plusmn; 0,04g para os grupos suplementados (S) e controle (C). Somente 52,17% das novilhas no grupo C (11 em 23) mas 95,65% no grupo S (22 em 23) alcançaram a maturidade sexual antes de 18 meses de idade (P<0,01). Os animais com tratamento antihelmíntico tiveram uma melhor desempenho no crescimento que os controles