Thermomechanical testing techniques for high-temparature composites: TMF behavior of SiC(SCS-6)/Ti-15-3

Thermomechanical testing techniques recently developed for monolithic structural alloys were successfully extended to continuous fiber reinforced composite materials in plate form. The success of this adaptation was verified on a model metal matrix composite (MMC) material, namely SiC(SCS-6)/Ti-15V-3Cr-3Al-3Sn. Effects of heating system type and specimen preparation are also addressed. Cyclic lives determined under full thermo-mechanical conditions were shown to be significantly reduced from those obtained under comparable isothermal and in-phase bi-thermal conditions. Fractography and metallography from specimens subjected to isothermal, out-of-phase and in-phase conditions reveal distinct differences in damage-failure modes. Isothermal metallography revealed extensive matrix cracking associated with fiber damage throughout the entire cross-section of the specimen. Out-of-phase metallography revealed extensive matrix damage associated with minimal (if any) fiber cracking. However, the damage was located exclusively at surface and near-surface locations. In-phase conditions produced extensive fiber cracking throughout the entire cross-section, associated with minimal (if any) matrix damage

Infrasonic observations of large-scale HE events

The Los Alamos Infrasound Program has been operating since about mid-1982, making routine measurements of low frequency atmospheric acoustic propagation. Generally, the authors work between 0.1 Hz to 10 Hz; however, much of the work is concerned with the narrower range of 0.5 to 5.0 Hz. Two permanent stations, St. George, UT, and Los Alamos, NM, have been operational since 1983, collecting data 24 hours a day. For the purposes of this discussion, the authors concentrate on their measurements of large, high explosive (HE) events at ranges of 250 km to 5330 km. Because their equipment is well suited for mobile deployments, they can easily establish temporary observing sites for special events. The measurements are from the permanent sites, as well as from various temporary sites. A few observations that are typical of the full data set are given

DOES SPORTSBOOK.COM SET POINTSPREADS TO MAXIMIZE PROFITS?

The Levitt (2004) model of sportsbook behavior is tested using actual percentages of dollars bet on NFL games from the internet sportsbook, Sportsbook.com.  Simple regression results suggest that Sportsbook.com sets pointspreads (prices) to maximize profits, as the Levitt model assumes, not to balance the betting dollars, as the traditional model of sportsbook behavior assumes.  Sportsbook.com is found to accept significantly more wagering dollars on road favorites, larger favorites, and on the over for the highest totals in the over/under betting market.  Bettor liquidity constraints and sportsbook betting limits may help explain this result.  

The Minor League Experience: What Drives Attendance at South Atlantic League Baseball Games?

An examination of the determinants of minor league baseball attendance in the South Atlantic League is performed through regression analysis. Potential determinants included in the regression model include demographic variables, team performance variables, and dummies for various categories of promotions. Overall, South Atlantic League baseball appears to be an inferior good, fans do not significantly respond to winning teams, fans do respond favorably to high-scoring games, and promotional events play a major role in attendance. The events that are shown to have the biggest impact at the gate are fireworks and concerts. It appears that the overall entertainment experience, not the success of the home team, is what attracts fans to South Atlantic League baseball games

Nuclear gene phylogeography using PHASE: dealing with unresolved genotypes, lost alleles, and systematic bias in parameter estimation

<p>Abstract</p> <p>Background</p> <p>A widely-used approach for screening nuclear DNA markers is to obtain sequence data and use bioinformatic algorithms to estimate which two alleles are present in heterozygous individuals. It is common practice to omit unresolved genotypes from downstream analyses, but the implications of this have not been investigated. We evaluated the haplotype reconstruction method implemented by PHASE in the context of phylogeographic applications. Empirical sequence datasets from five non-coding nuclear loci with gametic phase ascribed by molecular approaches were coupled with simulated datasets to investigate three key issues: (1) haplotype reconstruction error rates and the nature of inference errors, (2) dataset features and genotypic configurations that drive haplotype reconstruction uncertainty, and (3) impacts of omitting unresolved genotypes on levels of observed phylogenetic diversity and the accuracy of downstream phylogeographic analyses.</p> <p>Results</p> <p>We found that PHASE usually had very low false-positives (i.e., a low rate of confidently inferring haplotype pairs that were incorrect). The majority of genotypes that could not be resolved with high confidence included an allele occurring only once in a dataset, and genotypic configurations involving two low-frequency alleles were disproportionately represented in the pool of unresolved genotypes. The standard practice of omitting unresolved genotypes from downstream analyses can lead to considerable reductions in overall phylogenetic diversity that is skewed towards the loss of alleles with larger-than-average pairwise sequence divergences, and in turn, this causes systematic bias in estimates of important population genetic parameters.</p> <p>Conclusions</p> <p>A combination of experimental and computational approaches for resolving phase of segregating sites in phylogeographic applications is essential. We outline practical approaches to mitigating potential impacts of computational haplotype reconstruction on phylogeographic inferences. With targeted application of laboratory procedures that enable unambiguous phase determination via physical isolation of alleles from diploid PCR products, relatively little investment of time and effort is needed to overcome the observed biases.</p

Altered gene expression in the superior temporal gyrus in schizophrenia

Background: The superior temporal gyrus (STG), which encompasses the primary auditory cortex, is believed to be a major anatomical substrate for speech, language and communication. The STG connects to the limbic system (hippocampus and amygdala), the thalamus and neocortical association areas in the prefrontal cortex, all of which have been implicated in schizophrenia. Results: To identify altered mRNA expression in the superior temporal gyrus (STG) in schizophrenia, oligonucleotide microarrays were used with RNA from postmortem STG tissue from 7 individuals with schizophrenia and 7 matched non-psychiatric controls. Overall, there was a trend towards down-regulation in gene expression, and altered expression of genes involved in neurotransmission, neurodevelopment, and presynaptic function was identified. To confirm altered expression identified by microarray analysis, the mRNA expression levels of four genes, IPLA2γ, PIK31R1, Lin-7b and ATBF1, were semi-quantitatively measured using relative real-time PCR. A number of genes with altered expression in the STG were also shown to have similar changes in expression as shown in our previous study of peripheral blood lymphocytes in schizophrenia. Conclusion: This study has identified altered expression of genes in the STG involved in neurotransmission and neurodevelopment, and to a lesser extent presynaptic function, which further support the notion of these functions playing an integral role in the development of schizophrenia

A tandem duplication within the fibrillin 1 gene is associated with the mouse tight skin mutation.

Mice carrying the Tight skin (Tsk) mutation have thickened skin and visceral fibrosis resulting from an accumulation of extracellular matrix molecules. These and other connective tissue abnormalities have made Tskl + mice models for scleroderma, hereditary emphysema, and myocardial hypertrophy. Previously we localized Tsk to mouse chromosome 2 in a region syntenic with human chromosome 15. The microfibrillar glycoprotein gene, fibrillin 1 (FBN1), on human chromosome 15q, provided a candidate for the Tsk mutation. We now demonstrate that the Tsk chromosome harbors a 30- to 40-kb genomic duplication within the Fbn1 gene that results in a larger than normal in-frame Fbn1 transcript. These findings provide hypotheses to explain some of the phenotypic characteristics of Tskl + mice and the lethality of Tsk/Tsk embryos

Effects of Phosphate and Citrate on the Gelation Properties of Casein Micelles in Renneted Ultra-High Temperature (UHT) Sterilized Concentrated Milk

Milk was concentrated to 3X (volume reduction) by ultrafiltration. Disodium phosphate and sodium citrate were added, and the milk concemrates were homogenized. The concentrates were then heated at 135°C for 50 s in a labora· tory ultra-high temperature (UHT) heating system. Rennet gels were made from heated and unheated milk concentrates and their curd firmness measured using a Fonnagraph. Gel microstructures were ex:amined by electron microscopy. When rennet was added to unhomogenized milk concentrate before UHT heating, the resultant gel consisted of a strong protein network that encapsulated the fat globules. Pockets of milk serum were associated with the fat. Homogenization caused the fat droplets to be coated with casein micelles and become tied into the protein network as an integral pan of the gel structure. The microstructure of UHT milk concentrate gels was different from gels made from unheated milk. Gelation of UHT milk proceeded more slowly and the gels were weaker. Much of the casein in such samples had lost their micellar identity and was present as a homogeneous mass around the fat droplets. Large areas in the gel lacked protein network, which weakened the UHT milk gels. Samples with disodium phosphate added did not gel after UHT treatment, even if high concentrations of ren net were added. Samples with sodium citrate added formed only a weak rennet gel after UHT treatment

The effects of dietary fish oil on hepatic high density and low density lipoprotein receptor activities in the rat

AbstractRats were fed either a standard ration diet or that diet supplemented with 8% by wt of a marine fish oil or safflower oil. After 10 days, plasma triacylglycerols, total cholesterol, high density lipoprotein (HDL) cholesterol, hepatic cholesterol and fatty acid synthesis and hepatic low density lipoprotein (LDL) receptor activity were significantly depressed while HDL receptor activity was significantly increased in rats fed fish oil. Fish oil-induced effects on cholesterol metabolism in the rat therefore include reciprocal changes in the activities of hepatic LDL and HDL receptors