The Effects of Microbial Inoculation on Short-to-Long Fermentation and Aerobic Stability of Grass-Legume Silage Ensiled in Big Bales

Wilted (35.9 % DM and 2.6% WSC) moderately difficult to ensile grass-legume mixture (red clover, alfalfa and timothy 50:20:30) was ensiled in cylindrical big bales (1.2 m hight and 1.2 m diameter) with a weight about 700 kg. The crop was ensiled for 8, 32 and 120 days with or without a microbial inoculation (SiloSolve® FC containing Lactococcus lactis DSM 11037/1k2081 and Lactobacillus buchneri DSM 22501/1k20738 applied at 1.5×105 CFU g-1 forage). Ten bales per treatment were prepared for each fermentation period. After each period of ensiling the big bales were opened, sampled, and tested for fermentation parameters, yeast and mould counts and aerobic stability. Weight loss during fermentation and aerobic exposure were recorded and DM losses were calculated. After 8 days of fermentation, the addition of SiloSolve® FC showed only significant positive effects on pH, acetic and butyric acid, while after 32 and 120 days of fermentation periods, significant improvements of adding SiloSolve® FC were observed across all parameters investigated. The results show that SiloSolve® FC is an effective treatment to reduce ammonia, ethanol, and butyric acid production, to control yeast and mould growth, and to improve acetic acid levels with a resulting improved aerobic stability of grass-legume mixture fermented in big bales. Total lactic acid bacteria increased significantly and an appreciable decrease number of yeasts were detected in the inoculated silage at all fermentation time points and after aerobic exposure if compared with untreated silage. Reduction in yeast and mould population during anaerobic phase of silage fermentation and during silage aerobic exposure period appears to be the main reason for the improvement aerobic stability of the inoculated silage. Improved fermentation, reduced DM loss during fermentation and during aerobic exposure periods lead to increase nutritive value of the inoculated silage

Spatially Resolving the Inner Disk of TW Hya

We present Keck Interferometer observations of TW Hya that spatially resolve its emission at 2 micron wavelength. Analyzing these data together with existing K-band veiling and near-infrared photometric measurements, we conclude that the inner disk consists of optically thin, sub-micron-sized dust extending from ~4 AU to within 0.06 AU of the central star. The inner disk edge may be magnetospherically truncated. Even if we account for the presence of gas in the inner disk, these small dust grains have survival times against radiation blow-out that are orders of magnitude shorter than the age of the system, suggesting continual replenishment through collisions of larger bodies.Comment: 11 pages, including 2 figures. Accepted by ApJ

On Phase Transition of NH4H2PO4NH_{4}H_{2}PO_{4}-Type Crystals by Cluster Variation Method

The Cluster Variation Method (CVM) is applied to the Ishibashi model for ammonium dihydrogen phosphate ($\rm NH_{4}H_{2}PO_{4}$) of a typical hydrogen bonded anti-ferroelectric crystal. The staggered and the uniform susceptibility without hysteresis are calculated at equilibrium. On the other hand, by making use of the natural iteration method (NIM) for the CVM, hysteresis phenomena of uniform susceptibility versus temperature observed in experiments is well explained on the basis of local minimum in Landau type variational free energy. The polarization $P$ curves against the uniform field is also calculated.Comment: 14 pages, 10 figure

Observations of T Tauri Disks at Sub-AU Radii: Implications for Magnetospheric Accretion and Planet Formation

We determine inner disk sizes and temperatures for four solar-type (1-2 M$_{\odot}$) classical T Tauri stars (AS 207A, V2508 Oph, AS 205A, and PX Vul) using 2.2 $\mu$m observations from the Keck Interferometer. Nearly contemporaneous near-IR adaptive optics imaging photometry, optical photometry, and high-dispersion optical spectroscopy are used to distinguish contributions from the inner disks and central stars in the interferometric observations. In addition, the spectroscopic and photometric data provide estimates of stellar properties, mass accretion rates, and disk co-rotation radii. We model our interferometric and photometric data in the context of geometrically flat accretion disk models with inner holes, and flared disks with puffed-up inner walls. Models incorporating puffed-up inner disk walls generally provide better fits to the data, similar to previous results for higher-mass Herbig Ae stars. Our measured inner disk sizes are larger than disk truncation radii predicted by magnetospheric accretion models, with larger discrepancies for sources with higher mass accretion rates. We suggest that our measured sizes correspond to dust sublimation radii, and that optically-thin gaseous material may extend further inward to the magnetospheric truncation radii. Finally, our inner disk measurements constrain the location of terrestrial planet formation as well as potential mechanisms for halting giant planet migration.Comment: Accepted for publication in ApJ (May 1, 2005 issue

Common Cause Versus Dynamic Mutualism: An Empirical Comparison of Two Theories of Psychopathology in Two Large Longitudinal Cohorts

Mental disorders are among the leading causes of global disease burden. To respond effectively, a strong understanding of the structure of psychopathology is critical. We empirically compared two competing frameworks, dynamic-mutualism theory and common-cause theory, that vie to explain the development of psychopathology. We formalized these theories in statistical models and applied them to explain change in the general factor of psychopathology (p factor) from early to late adolescence ( N = 1,482) and major depression in middle adulthood and old age ( N = 6,443). Change in the p factor was better explained by mutualism according to model-fit indices. However, a core prediction of mutualism was not supported (i.e., predominantly positive causal interactions among distinct domains). The evidence for change in depression was more ambiguous. Our results support a multicausal approach to understanding psychopathology and showcase the value of translating theories into testable statistical models for understanding developmental processes in clinical sciences

Common cause versus dynamic mutualism:An empirical comparison of two theories of psychopathology in two large longitudinal cohorts

Stress and Psychopatholog

No Evidence That Substance Use Causes ADHD Symptoms in Adolescence

There is a robust association between attention-deficit hyperactivity disorder (ADHD) symptoms and elevated substance use. Several plausible causal pathways from ADHD to substance use have been articulated and supported empirically. In this study, we tested the recent suggestion that substance use could also influence levels of ADHD symptoms. Using the three most recent waves of data from the Zurich Project on the Social Development of Children and Youth (z-proso), we found significant and strong cross-lagged effects of ADHD symptoms on substance use but no significant effects in the opposite direction. This suggests that individual differences in substance use are not related to increases in ADHD symptoms in adolescence. Adolescent-onset symptoms of ADHD are thus unlikely to be caused by substance use, and targeting substance use problems is unlikely to reduce ADHD symptoms.Funding from the Jacobs Foundation (Grant 2010-888) and the Swiss National Science Foundation (Grants 100013_116829 & 100014_132124) is gratefully acknowledged

Embedded protostellar disks around (sub-)solar protostars. I. Disk structure and evolution

We perform a comparative numerical hydrodynamics study of embedded protostellar disks formed as a result of the gravitational collapse of cloud cores of distinct mass (M_cl=0.2--1.7 M_sun) and ratio of rotational to gravitational energy (\beta=0.0028--0.023). An increase in M_cl and/or \beta leads to the formation of protostellar disks that are more susceptible to gravitational instability. Disk fragmentation occurs in most models but its effect is often limited to the very early stage, with the fragments being either dispersed or driven onto the forming star during tens of orbital periods. Only cloud cores with high enough M_cl or \beta may eventually form wide-separation binary/multiple systems with low mass ratios and brown dwarf or sub-solar mass companions. It is feasible that such systems may eventually break up, giving birth to rogue brown dwarfs. Protostellar disks of {\it equal} age formed from cloud cores of greater mass (but equal \beta) are generally denser, hotter, larger, and more massive. On the other hand, protostellar disks formed from cloud cores of higher \beta (but equal M_cl) are generally thinner and colder but larger and more massive. In all models, the difference between the irradiation temperature and midplane temperature \triangle T is small, except for the innermost regions of young disks, dense fragments, and disk's outer edge where \triangle T is negative and may reach a factor of two or even more. Gravitationally unstable, embedded disks show radial pulsations, the amplitude of which increases along the line of increasing M_cl and \beta but tends to diminish as the envelope clears. We find that single stars with a disk-to-star mass ratio of order unity can be formed only from high-\beta cloud cores, but such massive disks are unstable and quickly fragment into binary/multiple systems.Comment: Accepted for publication in the astrophysical Journa