Heavy metal tissue distributions in southwestern Alaskan waterfowl: total mercury assays from muscle, brain, and bone

Thesis (M.S.) University of Alaska Fairbanks, 2005Food containing mercury has been identified as a possible health risk. Total mercury (THg), which is inorganic (Hg²), and methylmercury (MeHg) species, has been found in the arctic food web. In Alaska, birds are an important seasonal component of the diet, but have not been studied extensively and characterized for the presence of mercury. Birds are good subjects for examination because they feed at different trophic levels, can be long-lived, and are both abundant and widely distributed. Not only can birds monitor local Alaskan food webs, but, if they are migratory, can be used to compare exposure in different regions. Mercury levels in muscle, brain, and bone tissue of 140 birds taken by subsistence hunters across southwestern Alaska were determined. I tested the null hypothesis of no interspecific differences in total mercury levels in the 18 species of Alaska birds surveyed. There were interspecific differences with the Lesser Scaup (Aythyra marila mariloides), and the Black Scoter (Melanita nigra Americana), having the highest levels of mercury. In general, mercury levels were higher in muscle than in brain or bone. The mean values for mercury in the species studied were lower than the levels known to cause adverse reproductive or behavioral effects

Using Molecular Marker Technology for Improvement in Sow Reproductive Longevity

The longevity or productive life of sows is one of the important components that contribute to the economic bottom line of swine production. Involuntary sow culling rates caused by locomotion failure, reproductive failure or death have been growing in recent years causing many females to be culled before they reach their most productive parities and before the investment costs of those females have been recovered. In addition to factors such as management, sow condition, health, nutrition, and facilities, there are likely to be genetic components controlling sow longevity that have yet to be fully identified. Research ongoing at Iowa State University, in conjunction with Sygen and PIC, has focused on identifying the genes associated with variation in sow longevity

Two ~35 day clocks in Her X-1: evidence for neutron star free precession

We present evidence for the existence of two ~35 day clocks in the Her X-1/HZ Her binary system. ~35 day modulations are observed 1) in the Turn-On cycles with two on- and two off-states, and 2) in the changing shape of the pulse profiles which re-appears regularly. The two ways of counting the 35 day cycles are generally in synchronization. This synchronization did apparently break down temporarily during the long Anomalous Low (AL3) which Her X-1 experienced in 1999/2000, in the sense that there must have been one extra Turn-On cycle. Our working hypothesis is that there are two clocks in the system, both with a period of about ~35 days: precession of the accretion disk (the less stable "Turn-On clock") and free precession of the neutron star (the more stable "Pulse profile clock"). We suggest that free precession of the neutron star is the master clock, and that the precession of the accretion disk is basically synchronized to that of the neutron star through a feed-back mechanism in the binary system. However, the Turn-On clock can slip against its master when the accretion disk has a very low inclination, as is observed to be the case during AL3. We take the apparent correlation between the histories of the Turn-Ons, of the Anomalous Lows and of the pulse period evolution, with a 5 yr quasi-periodicity, as evidence for strong physical interaction and feed-back between the major components in the system. We speculate that the 5 yr (10 yr) period is either due to a corresponding activity cycle of HZ Her or a natural ringing period of the physical system of coupled components. The question whether free precession really exists in neutron stars is of great importance for the understanding of matter with supra-nuclear density.Comment: 6 pages, 5 figures, accepted for publication by A&

Rapid Communication: The Very-Long-Chain Acyl-CoA Dehydrogenase Gene Maps to Pig Chromosome 12

Source and Description of Primers. Primers for the very-long-chain acyl-CoA dehydrogenase (ACADVL) gene were designed from a bovine cDNA sequence (GenBank accession No. U30817) aligned with the human ACADVL gene (GenBank accession No. L46590). The forward primer was 5¢-TTT GGG GAG AAA ATT CAC AAC-3¢ and the reverse primer was 5¢-GCG GCC TCT ATC TGG AAG T-3¢. The amplification product was expected to span from exon 11 to exon 12 of the ACADVL gene. Exonic parts (103 bp) of the pig sequence were 91% identical at the nucleotide level with the human ACADVL sequence. The pig sequence produced here has been submitted to GenBank (accession no. AF022255)

Rapid Communication: A HincII Polymorphism in the Porcine Calpain, Large Polypeptide L3 (CAPN3) Gene

Source and Description of Primers. Primers were designed from a published, partial porcine cDNA sequence (Genbank accession no. U05678) in positions corresponding to exons 11 and 13 of the human CAPN3 gene (Genbank accession no. X85030). Sequences were obtained from the ends of the PCR fragment and compared with the porcine cDNA sequence showing 98.1% identity in a 108-bp overlap at the exon 11 end and 99.2% identity in a 124-bp overlap at the exon 13 end. Sequences produced in this study have been submitted to Genbank (accession no. AF025660-AF025661)

Mapping of Two High Mobility Group Protein Genes for Growth and Composition traits in Pig

Using information from the human genome two new candidate genes for growth and composition traits were studied. The porcine high mobility group isoforms protein [HMGI(Y) and HMGIC] genes were chosen based on their presumed role in fat cell growth and differentiation. The HMGI(Y) gene was assigned to pig chromosome 7 by both linkage and physical mapping methods. This assignment agrees with other comparative mapping studies as the human HMGI(Y) gene maps to human chromosome 6p21, which is known to share a homology with pig chromosome 7. Interestingly, the pig HMGIC gene was assigned to the pig chromosome 1 by both methods. The localization of these candidate genes in the pig genome could improve the power of analyses for quantitative traits associated with growth and meat quality traits

Variable pulse profiles of Her X-1 repeating with the same irregular 35d clock as the turn-ons

The accreting X-ray pulsar Her X-1 shows two types of long-term variations, both with periods of ~35 days: 1) Turn-on cycles, a modulation of the flux}, with a ten-day long Main-On and a five-day long Short-On, separated by two Off-states, and 2) a systematic variation in the shape of the 1.24 s pulse profile. While there is general consensus that the flux modulation is due to variable shading of the X-ray emitting regions on the surface of the neutron star by the precessing accretion disk, the physical reason for the variation in the pulse profiles has remained controversial. Following the suggestion that free precession of the neutron star may be responsible for the variation in the pulse profiles, we developed a physical model of strong feedback interaction between the neutron star and the accretion disk in order to explain the seemingly identical values for the periods of the two types of variations, which were found to be in basic synchronization. In a deep analysis of pulse profiles observed by several different satellites over the last three decades we now find that the clock behind the pulse profile variations shows exactly the same erratic behavior as the turn-on clock, even on short time scales (a few 35 d cycles), suggesting that there may in fact be only one 35 d clock in the system. If this is true, it raises serious questions with respect to the idea of free precession of the neutron star, namely how the neutron star can change its precessional period every few years by up to 2.5% and how the feedback can be so strong, such that these changes can be transmitted to the accretion disk on rather short time scales.Comment: 9 pages, 13 figures, accepted by Astronomy & Astrophysics. arXiv admin note: substantial text overlap with arXiv:1110.671

Mapping five new candidate genes in the pig

Five new candidate genes for growth and carcass traits have recently been mapped in the pig by using either linkage analysis or analysis of a hybrid cell line panel. The genes mapped include the very long chain acyl-CoA dehydrogenase gene (ACADVL) mapped to pig chromosome 12, the adenylate cyclase activating peptide, pituitary 1 gene (ADCYAP1) on chromosome 6, the calpain large polypeptide L3 gene (CAPN3), the myocyte-specific enhancer factor 2A gene (MEF2A) on chromosome 1, and the thyroid stimulating hormone receptor gene (TSHR) on chromosome 7. All five genes have the potential to influence carcass traits in the pig. Future studies will be conducted to investigate if any of the genes actually do influence these traits

Recognition as a Measure of Learning from Television Commercials.

This is the published version. Copyright 1983 American Marketing Association.Recognition has not received extensive acceptance by practitioners as a response variable for learning of television commercials. The authors review some of the distinctions between recoil and recognition, and some of the problems associated with each. In a laboratory experiment they developed and tested a measure of recognition useful for low involvement situations in which a recall level of learning may not be necessary. Data and implications about the usefulness and limitations of the measure are presented