A Planetary Companion to the Nearby M4 Dwarf, Gliese 876

Doppler measurements of the M4 dwarf star, Gliese 876, taken at both Lick and Keck Observatory reveal periodic, Keplerian velocity variations with a period of 61 days. The orbital fit implies that the companion has a mass of, M = 2.1 MJUP /sin i, an orbital eccentricity of, e = 0.27+-0.03, and a semimajor axis of, a = 0.21 AU. The planet is the first found around an M dwarf, and was drawn from a survey of 24 such stars at Lick Observatory. It is the closest extrasolar planet yet found, providing opportunities for follow--up detection. The presence of a giant planet on a non-circular orbit, 0.2 AU from a 1/3 M_Sun star, presents a challenge to planet formation theory. This planet detection around an M dwarf suggests that giant planets are numerous in the Galaxy.Comment: 13 pages, 3 Figure

Uric Acid as a Potential Peripheral Biomarker for Disease Features in Huntington's Patients.

Oxidative stress has long been implicated in the pathophysiology and progression of Huntington's disease (HD). Uric acid (UA) is a naturally occurring antioxidant that is present in the brain and periphery. Growing evidence has implicated UA as a molecular biomarker for several neurodegenerative diseases, most notably Parkinson's disease (PD). In this study, we investigated UA levels in clinical samples from HD patients and normal controls (NCs) and assessed potential relationships between UA levels and disease and clinical data. UA levels were measured in plasma (n = 107) and saliva (n = 178) samples from premanifest (pre-HD) and manifest HD patients and control subjects. Gender effects of UA levels were observed in both biofluids, with male patients showing higher UA levels compared to female patients. Comparisons of UA levels across diagnostic groups, separated by gender, revealed that both plasma and salivary UA levels were significantly lower in female pre-HD and manifest HD patients compared to NCs. Salivary levels of UA were also significantly lower in male manifest HD patients versus controls, but not in plasma. Correlations of peripheral UA levels to clinical data also showed differences according to gender. In male HD patients, both plasma and salivary UA levels were significantly negatively correlated with total functional capacity (TFC), while positive correlations were observed with total motor score (TMS). Female HD patients showed a significant positive correlation between plasma UA levels and TMS, while salivary UA levels from female patients were significantly correlated to disease burden. Finally, in a separate cohort, we show that UA levels are decreased in postmortem prefrontal cortical samples (n = 20) from HD subjects compared to matched controls. These findings suggest that decreased levels of UA in the brains of HD patients can be reflected in peripheral fluids, with salivary measures of UA particularly offering significant promise as a potentially relevant, non-invasive biomarker of disease symptoms and burden. Our findings further highlight the impact of sexual dimorphism in HD pathophysiology

On the 2:1 Orbital Resonance in the HD 82943 Planetary System

We present an analysis of the HD 82943 planetary system based on a radial velocity data set that combines new measurements obtained with the Keck telescope and the CORALIE measurements published in graphical form. We examine simultaneously the goodness of fit and the dynamical properties of the best-fit double-Keplerian model as a function of the poorly constrained eccentricity and argument of periapse of the outer planet's orbit. The fit with the minimum chi_{nu}^2 is dynamically unstable if the orbits are assumed to be coplanar. However, the minimum is relatively shallow, and there is a wide range of fits outside the minimum with reasonable chi_{nu}^2. For an assumed coplanar inclination i = 30 deg. (sin i = 0.5), only good fits with both of the lowest order, eccentricity-type mean-motion resonance variables at the 2:1 commensurability, theta_1 and theta_2, librating about 0 deg. are stable. For sin i = 1, there are also some good fits with only theta_1 (involving the inner planet's periapse longitude) librating that are stable for at least 10^8 years. The libration semiamplitudes are about 6 deg. for theta_1 and 10 deg. for theta_2 for the stable good fit with the smallest libration amplitudes of both theta_1 and theta_2. We do not find any good fits that are non-resonant and stable. Thus the two planets in the HD 82943 system are almost certainly in 2:1 mean-motion resonance, with at least theta_1 librating, and the observations may even be consistent with small-amplitude librations of both theta_1 and theta_2.Comment: 24 pages, including 10 figures; accepted for publication in Ap

Comparison of Swine Performance When Fed Diets Containing Corn Root Worm Protected Corn, Parental Line Corn, or Conventional Corn Grown During 2000 in Nebraska

This experiment was conducted to evaluate growth performance and carcass quality measurements in growing-finishing pigs fed diets containing either Corn Root Worm Protected Corn (CRW0586), the parental control corn (RX670), or two commercial sources of non-genetically modified corn (DK647 and RX740). The experiment used 72 barrows and 72 gilts with an average initial body weight of 50 lb. The pigs were allotted to a randomized complete block design with a 2 x 4 factorial arrangement of treatments (two sexes x four corn hybrids). The experiment continued until the average body weight was 260 lb, at which time all pigs were slaughtered. Real-time ultrasound measurements were taken on the final day of the experiment. Carcass quality measurements were made 24 hours postmortem. Corn hybrid did not affect average daily gain (ADG) or average daily feed intake (ADFI), but there was an effect of sex, with barrows having greater (P\u3c0.01) ADG and ADFI than gilts. Feed efficiency was not affected by the different corn hybrids, but gilts had improved (P\u3c0.01) feed efficiency compared to barrows during Finisher 1 (0.37 versus 0.35) and Finisher 2 (0.32 versus 0.30). Real-time ultrasound measurements were similar corns; however, a sex effect was detected for backfat (BF) depth, with gilts having less (P\u3c0.01) BJ than barrows (0.78 versus 0.98 in). There were no differences in carcass midline BF measurements among corns, but there was a significant difference between barrows and gilts, with gilts having less (P\u3c0.05) BF than barrows. Hot carcass weight was greater (P\u3c0.01) in barrows than gilts (210 versus 190 lb). Also, the percent carcass lean was greater (P\u3c0.01) in gilts than barrows (51.7 versus 49.5%). Longissimus muscle quality scores were similar among corns and between barrows and gilts. Analysis of longissimus muscle composition revealed no main effect of corn (P\u3e0.20) or sex (P\u3e0.30) for protein, fat, and water percentages. However, Corn Root Worm Protected Corn (73.1%) differed (P\u3c0.04) from parental control corn (73.6%) but not commercial corns (73.3 and 73.3%) in longissimus water content. In summary, there were no differences in growth performance or carcass measurements in growing-finishing pigs fed diets containing either Corn Root Worm Protected Corn, the parental control corn, or two commercial sources of non-genetically modified corn. Thus, the replacement of non-genetically modified corn. Thus, the replacement of non-transgenic corn with Corn Root Worm Protected Corn in growing-finishing diets will result in similar growth performance and(or) carcass measurements

Scaling Functions for Baby Universes in Two-Dimensional Quantum Gravity

We apply the recently proposed transfer matrix formalism to 2-dimensional quantum gravity coupled to $(2, 2k-1)$ minimal models. We find that the propagation of a parent universe in geodesic (Euclidean) time is accompanied by continual emission of baby universes and derive a distribution function describing their sizes. The $k\to \infty~ (c\to -\infty)$ limit is generally thought to correspond to classical geometry, and we indeed find a classical peak in the universe distribution function. However, we also observe dramatic quantum effects associated with baby universes at finite length scales.Comment: 20 pages, 6 figures (not included, available upon request), PUPT-142

Planetary Companions Around Two Solar Type Stars: HD 195019 and HD 217107

We have enlarged the sample of stars in the planet search at Lick Observatory. Doppler measurements of 82 new stars observed at Lick Observatory, with additional velocities from Keck Observatory, have revealed two new planet candidates. The G3V/IV star, HD 195019, exhibits Keplerian velocity variations with a period of 18.27 d, an orbital eccentricity of 0.03 +/- 0.03, and M sin i = 3.51 M_Jup. Based on a measurement of Ca II H&K emission, this star is chromospherically inactive. We estimate the metallicity of HD 195019 to be approximately solar from ubvy photometry. The second planet candidate was detected around HD 217107, a G7V star. This star exhibits a 7.12 d Keplerian period with eccentricity 0.14 +/- 0.05 and M sin i = 1.27 M_Jup. HD 217107 is also chromospherically inactive. The photometric metallicity is found to be [Fe/H] = +0.29 +/- 0.1 dex. Given the relatively short orbital period, the absence of tidal spin-up of HD 217107 provides a theoretical constraint on the upper limit of the companion mass of < 11 M_Jup.Comment: 15 pages, plus 6 figures. To appear in Jan 1999 PAS

Fourteen New Companions from the Keck & Lick Radial Velocity Survey Including Five Brown Dwarf Candidates

We present radial velocities for 14 stars on the California & Carnegie Planet Search target list that reveal new companions. One star, HD 167665, was fit with a definitive Keplerian orbit leading to a minimum mass for the companion of 50.3 Mjup at a separation from its host of ~5.5 AU. Incomplete or limited phase coverage for the remaining 13 stars prevents us from assigning to them unique orbital parameters. Instead, we fit their radial velocities with Keplerian orbits across a grid of fixed values for Msini and period, P, and use the resulting reduced chi-square surface to place constraints on Msini, P, and semimajor axis, a. This technique allowed us to restrict Msini below the brown dwarf -- stellar mass boundary for an additional 4 companions (HD 150554, HD 8765, HD 72780, HD 74014). If the combined 5 companions are confirmed as brown dwarfs, these results would comprise the first major catch of such objects from our survey beyond ~3 AU.Comment: 29 pages, 14 figures, accepted to Ap

Untargeted Plasma Metabolite Profiling Reveals the Broad Systemic Consequences of Xanthine Oxidoreductase Inactivation in Mice

A major challenge in systems biology is integration of molecular findings for individual enzyme activities into a cohesive high-level understanding of cellular metabolism and physiology/pathophysiology. However, meaningful prediction for how a perturbed enzyme activity will globally impact metabolism in a cell, tissue or intact organisms is precluded by multiple unknowns, including in vivo enzymatic rates, subcellular distribution and pathway interactions. To address this challenge, metabolomics offers the potential to simultaneously survey changes in thousands of structurally diverse metabolites within complex biological matrices. The present study assessed the capability of untargeted plasma metabolite profiling to discover systemic changes arising from inactivation of xanthine oxidoreductase (XOR), an enzyme that catalyzes the final steps in purine degradation. Using LC-MS coupled with a multivariate statistical data analysis platform, we confidently surveyed >3,700 plasma metabolites (50–1,000 Da) for differential expression in XOR wildtype vs. mice with inactivated XOR, arising from gene deletion or pharmacological inhibition. Results confirmed the predicted derangements in purine metabolism, but also revealed unanticipated perturbations in metabolism of pyrimidines, nicotinamides, tryptophan, phospholipids, Krebs and urea cycles, and revealed kidney dysfunction biomarkers. Histochemical studies confirmed and characterized kidney failure in xor-nullizygous mice. These findings provide new insight into XOR functions and demonstrate the power of untargeted metabolite profiling for systemic discovery of direct and indirect consequences of gene mutations and drug treatments

Two Jovian-Mass Planets in Earthlike Orbits

We report the discovery of two new planets: a 1.94 M_Jup planet in a 1.8-year orbit of HD 5319, and a 2.51 M_Jup planet in a 1.1-year orbit of HD 75898. The measured eccentricities are 0.12 for HD 5319 b and 0.10 for HD 75898 b, and Markov Chain Monte Carlo simulations based on derived orbital parameters indicate that the radial velocities of both stars are consistent with circular planet orbits. With low eccentricity and 1 < a < 2 AU, our new planets have orbits similar to terrestrial planets in the solar system. The radial velocity residuals of both stars have significant trends, likely arising from substellar or low-mass stellar companions.Comment: 32 pages, including 11 figures and 5 tables. Accepted by Ap