The Effects of Thawing Procedure and Supplementation on the Motility and Viability of Frozen-thawed Boar Semen

The effect of two thawing procedures on frozen boar semen and supplementations to the fertilization media were studied. Frozen boar semen was thawed using either Percoll gradient or phosphate buffered saline (PBS)procedure. Supplementations were 1.0 mM L-glutamate, 1.0 mM N-acetylcysteine (NAC) , and 1.0 mM NAC-amide (NACA). Spermatozoa were analyzed for forward progressive motility (FPM) and viability every 0.5 h for 3 .0 h post-thawing. There were significantly (P \u3c 0.05) higher numbers of viable (76.0 ± 5.1 %) and FPM (30 .0 ± 2.4%) spermatozoa at 3.0 h post thawing using the PBS procedure compared to the Percoll gradient thawed spermatozoa (65.0 ± 3.9%; 10.0 ± 4.5 %, respectively). Supplementation of 1.0 mM L-glutamate, 1.0 mM NAC, or 1.0 mM NACA had no significant effect on spermatozoa viability regardless of the time post-thaw.Supplementation of 1.0 mM L-glutamate, 1.0 mM NAC , or 1.0 mM NACA had no significant effect on FPM up to 1.0 h post-thaw. Spermatozoa with no supplementation or 1.0 mM L-glutamate had significantly higher (P \u3c 0.05) FPM compared to the 1.0 mM NAC and 1.0 mM NACA supplemented groups at 1.5, 2.0, 2 .5, and 3.0 h post-thaw. There was no significant difference between no supplementation or 1.0 mM L-glutamate on FPM regardless of the time post-thaw. There was no significant difference between 1.0 mM NAC or 1.0 mM NACA on FPM regardless of the time post-thaw. These results indicate that thawing procedure has an effect on spermatozoa viability and FPM but supplementation does not have an effect on the overall viability of spermatozoa during thawing, but may reduce FPM

Localizing the Latent Structure Canonical Uncertainty: Entropy Profiles for Hidden Markov Models

This report addresses state inference for hidden Markov models. These models rely on unobserved states, which often have a meaningful interpretation. This makes it necessary to develop diagnostic tools for quantification of state uncertainty. The entropy of the state sequence that explains an observed sequence for a given hidden Markov chain model can be considered as the canonical measure of state sequence uncertainty. This canonical measure of state sequence uncertainty is not reflected by the classic multivariate state profiles computed by the smoothing algorithm, which summarizes the possible state sequences. Here, we introduce a new type of profiles which have the following properties: (i) these profiles of conditional entropies are a decomposition of the canonical measure of state sequence uncertainty along the sequence and makes it possible to localize this uncertainty, (ii) these profiles are univariate and thus remain easily interpretable on tree structures. We show how to extend the smoothing algorithms for hidden Markov chain and tree models to compute these entropy profiles efficiently.Comment: Submitted to Journal of Machine Learning Research; No RR-7896 (2012

METALLOGRAPHIC EXAMINATION OF ORNL NO. 1, SHE NO. 2

Small Heat Exchanger ORNL No. I, type SHE No. 2, was removed from test stand B after 2071 hours of operation; 1041 hours were under 4 T conditions. The heat exchanger contatned 20 Inconel tubes having an outside diameter of 0.25 in. and a wall thickness of 0.025 in. The outside of these tubes was exposed to the fluoride mixture NaF contained NaK (44% Na--56% K). During o degradation t T conditions, the fluoride temperature entering the heat exchanger was 1310 tained F and on leaving was 1235 tained F. The temperature of the NaK entering the heat exchanger was 1050 tained F and at the exit was 1290 tained F. During isothermal operation, the temperature of both the NaK and fluoride circuits was 1300 tained F. Thirtysix termperature transitions from isothermal to o degradation t T conditions were made during the course of operation. An examination of the resistance heater used in conjunction with this heat exchanger also was made: the results are reported. (auth

LIPOGENESIS IN ADIPOSE TISSUE FROM OVARIECTOMIZED AND INTACT HEIFERS IMMUNIZED AGAINST ESTRADIOL AND(OR) IMPLANTED WITH TRENBOLONE ACETATE

Forty-two heifers were allotted randomly to six treatment groups: 1) intact controls, 2) intact heifers implanted with trenbolone acetate, 3) ovariectomized heifers, 4) ovariectomized heifers implanted with trenbolone acetate, 5) intact heifers immunized against estradiol and 6) intact heifers immunized against estradiol and implanted with trenbolone acetate. Blood titers of estradiol-17β were increased over lO0-fold in heifers immunized against estradiol in Freund\u27s complete adjuvant or saline:squalene/arlacel containing Mycobacterium. Lipogenic enzyme activities and acetate incorporation into fatty acids were increased in subcutaneous adipose tissue obtained at slaughter from heifers receiving immunization or the combination of immunization and trenbolone acetate. The increased lipogenic capacity was not reflected in either cell diameter or cells per gram adipose tissue. Ovariectomy in combination with trenbolone acetate caused the lowest activities for all enzymes measured. This treatments also caused the greatest decrease in cell diameter, which resulted in the largest number of cells per gram of adipose tissue. Trenbotone acetate alone had no detectable effect on lipogenesis in the intact heifer, but the combination of ovariectomy and trenbolone acetate caused substantial decreases in enzyme activities, in most cases a significant decrease as compared with ovariectomized heifers. The data suggest that trenbolone acetate is able to depress lipogenesis only when not competing with the effects of circulating estradiol

LIPOGENESIS IN ADIPOSE TISSUE FROM OVARIECTOMIZED AND INTACT HEIFERS IMMUNIZED AGAINST ESTRADIOL AND(OR) IMPLANTED WITH TRENBOLONE ACETATE

Forty-two heifers were allotted randomly to six treatment groups: 1) intact controls, 2) intact heifers implanted with trenbolone acetate, 3) ovariectomized heifers, 4) ovariectomized heifers implanted with trenbolone acetate, 5) intact heifers immunized against estradiol and 6) intact heifers immunized against estradiol and implanted with trenbolone acetate. Blood titers of estradiol-17β were increased over lO0-fold in heifers immunized against estradiol in Freund\u27s complete adjuvant or saline:squalene/arlacel containing Mycobacterium. Lipogenic enzyme activities and acetate incorporation into fatty acids were increased in subcutaneous adipose tissue obtained at slaughter from heifers receiving immunization or the combination of immunization and trenbolone acetate. The increased lipogenic capacity was not reflected in either cell diameter or cells per gram adipose tissue. Ovariectomy in combination with trenbolone acetate caused the lowest activities for all enzymes measured. This treatments also caused the greatest decrease in cell diameter, which resulted in the largest number of cells per gram of adipose tissue. Trenbotone acetate alone had no detectable effect on lipogenesis in the intact heifer, but the combination of ovariectomy and trenbolone acetate caused substantial decreases in enzyme activities, in most cases a significant decrease as compared with ovariectomized heifers. The data suggest that trenbolone acetate is able to depress lipogenesis only when not competing with the effects of circulating estradiol

Structured Sparsity: Discrete and Convex approaches

Compressive sensing (CS) exploits sparsity to recover sparse or compressible signals from dimensionality reducing, non-adaptive sensing mechanisms. Sparsity is also used to enhance interpretability in machine learning and statistics applications: While the ambient dimension is vast in modern data analysis problems, the relevant information therein typically resides in a much lower dimensional space. However, many solutions proposed nowadays do not leverage the true underlying structure. Recent results in CS extend the simple sparsity idea to more sophisticated {\em structured} sparsity models, which describe the interdependency between the nonzero components of a signal, allowing to increase the interpretability of the results and lead to better recovery performance. In order to better understand the impact of structured sparsity, in this chapter we analyze the connections between the discrete models and their convex relaxations, highlighting their relative advantages. We start with the general group sparse model and then elaborate on two important special cases: the dispersive and the hierarchical models. For each, we present the models in their discrete nature, discuss how to solve the ensuing discrete problems and then describe convex relaxations. We also consider more general structures as defined by set functions and present their convex proxies. Further, we discuss efficient optimization solutions for structured sparsity problems and illustrate structured sparsity in action via three applications.Comment: 30 pages, 18 figure

Evaluating the Plausible Range of N2O Biosignatures on Exo-Earths: An Integrated Biogeochemical, Photochemical, and Spectral Modeling Approach

Nitrous oxide (N2O) -- a product of microbial nitrogen metabolism -- is a compelling exoplanet biosignature gas with distinctive spectral features in the near- and mid-infrared, and only minor abiotic sources on Earth. Previous investigations of N2O as a biosignature have examined scenarios using Earthlike N2O mixing ratios or surface fluxes, or those inferred from Earth's geologic record. However, biological fluxes of N2O could be substantially higher, due to a lack of metal catalysts or if the last step of the denitrification metabolism that yields N2 from N2O had never evolved. Here, we use a global biogeochemical model coupled with photochemical and spectral models to systematically quantify the limits of plausible N2O abundances and spectral detectability for Earth analogs orbiting main-sequence (FGKM) stars. We examine N2O buildup over a range of oxygen conditions (1%-100% present atmospheric level) and N2O fluxes (0.01-100 teramole per year; Tmol = 10^12 mole) that are compatible with Earth's history. We find that N2O fluxes of 10 [100] Tmol yr$^{-1}$ would lead to maximum N2O abundances of ~5 [50] ppm for Earth-Sun analogs, 90 [1600] ppm for Earths around late K dwarfs, and 30 [300] ppm for an Earthlike TRAPPIST-1e. We simulate emission and transmission spectra for intermediate and maximum N2O concentrations that are relevant to current and future space-based telescopes. We calculate the detectability of N2O spectral features for high-flux scenarios for TRAPPIST-1e with JWST. We review potential false positives, including chemodenitrification and abiotic production via stellar activity, and identify key spectral and contextual discriminants to confirm or refute the biogenicity of the observed N2O.Comment: 22 pages, 17 figures; ApJ, 937, 10

Insulators and imprinting from flies to mammals

The nuclear factor CTCF has been shown to be necessary for the maintenance of genetic imprinting at the mammalian H19/Igf2 locus. MacDonald and colleagues now report in BMC Biology that the mechanisms responsible for maintaining the imprinted state in Drosophila may be evolutionarily conserved and that CTCF may also play a critical role in this process