Reflected Light from Giant Planets in Habitable Zones: Tapping into the Power of the Cross-Correlation Function.

The direct detection of reflected light from exoplanets is an excellent probe for the characterization of their atmospheres. The greatest challenge for this task is the low planet-to-star flux ratio, which even in the most favourable case is of the order of 10-4 in the optical. This ratio decreases even more for planets in their host's habitable zone, typically lower than 10-7. To reach the signal-to-noise level required for such detections, we propose to unleash the power of the Cross Correlation Function in combination with the collecting power of next generation observing facilities. The technique we propose has already yielded positive results by detecting the reflected spectral signature of 51 Pegasi b (see Martins et al. 2015). In this work, we attempted to infer the number of hours required for the detection of several planets in their host's habitable zone using the aforementioned technique from theoretical EELT observations. Our results show that for 5 of the selected planets it should be possible to directly recover their reflected spectral signature.

Impact of puberty status and melengestrol acetate supplementation before the breeding period on reproductive efficiency of Bos indicus beef heifers.

Two experiments were designed to evaluate the impact of puberty status and the administration of melengestrol acetate (MGA) before onset of the breeding period on ovulatory responses (Exp. 1) and conception rate after AI performed on estrus detection during 10 d and the pregnancy rate through 80 d of breeding period (Exp. 2) of pasture-grazed beef heifers. In Exp. 1, heifers (15 pubertal and 15 prepubertal) received 0.5 mg per heifer/d -1 of MGA over 14 d. No differences in the ovulatory responses were found 10 d after the MGA administration (pubertal = 46.7% vs. prepubertal P = 53.3%; P = 0.72). In Exp. 2, 368 heifers were randomly assigned to groups according to pubertal status and the MGA treatment. All heifers were inseminated on estrus detection for up 10 d after MGA administration and following exposure to bulls between 20 and 80 d. The MGA-treated heifers exhibited a greater AI service rate than control heifers (72.1 vs. 41.6%;P < 0.01); however, heifers receiving MGA had lower conception results following AI (51.6 vs. 71.4%; P = 0.01). In addition, MGA-treated heifers were more likely to have a corpus luteum in the middle of the breeding period (95.3 vs. 87.5%;P < 0.01), although the Cox proportional hazard of pregnancy rate was similar (P = 0.29) at the end of the breeding period. At onset of the breeding period, pubertal heifers presented a greater pregnancy rate following AI (pubertal P = 42.2% vs. prepubertal P = 24.9%; P = 0.01). Therefore, pubertal heifers seem to have greater overall reproductive efficiency than prepubertal heifers, particularly at the beginning of the breeding period. Interestingly, administration of MGA before the onset of the breeding period increased AI service rate but did not alter the rate of pregnancy throughout the breeding period of pasture-grazed beef heifers.