COMPUTER APPLICATIONS IN QUANTITATIVE EPR SPECTROSCOPY OF METALLOPROTEINS (FERRITIN, APOFERRITIN, IRON)

This dissertation examines the use of computers in quantitative EPR spectroscopy. The computers used ranged from hand held calculators to large main frame systems. Applications discussed are protein assay calculations, an EPR minicomputer interface and software system and the modification of an existing EPR simulation program to include corrections for strains in the g and A tensors. The modification permits more accurate linewidth simulation for lines with large M(,I) values. The computer interface and software allows for the collection of EPR spectra, which can then be stored, scaled, added, subtracted (for comparison) and double integrated. The program enhances weak signals by signal averaging. Double integration was used to assist in the study of early iron binding in horse spleen apoferritin. Iron(II) was added to apoferritin followed by oxidation by a variety of methods. In all cases an iron(III) EPR signal was observed at g\u27 = 4.3 which was attributed to mononuclear Fe(III) bound to the protein; this signal increased until 0.5 equivalent per subunit of added iron. In another experiment increasing amounts of Tb(III) were added to apoferritin solutions. Subsequent addition of 0.5 equivalent of iron(II) per subunit resulted in an Fe(III) signal that decreased as a function of added Tb(III). It was also found that ultracentrifugation of commercial ferritin yields a light, low iron content, fraction which showed a majority of the iron signal intensity relative to the heavy, iron rich, fraction. These results suggest that iron core starts to form at an initial binding site that lies between two adjacent subunits resulting in a 0.5 equivalent of binding site per subunit and that this site also serves as the nucleus of core formation within the ferritin molecule. As the core grows beyond 0.5 equivalents per subunit more of the mononuclear sites are converted into growing core. At 0.5 equivalents per subunit double integration shows that only 20% of the added iron is EPR active suggesting a majority of the added iron is present as polymeric iron (core) species

An Empirical Study of Dynamic Scheduling on Rings of Processors

The authors empirically analyze and compare two distributed low-overhead policies for scheduling dynamic tree-structured computations on rings of identical PEs. The experiments show that both policies give significant parallel speedup on large classes of computations, and that one yields almost optimal speedup on moderate size rings. They believe that the methodology of experiment design and analysis will prove useful in other such studies

Galaxy pairs in the Sloan Digital Sky Survey – X. Does gas content alter star formation rate enhancement in galaxy interactions?

New spectral line observations, obtained with the Jansky Very Large Array (VLA), of a sample of 34 galaxies in 17 close pairs are presented in this paper. The sample of galaxy pairs is selected to contain galaxies in close, major interactions (i.e. projected separations 3σ. We compare the H i gas fraction of the galaxies with the triggered star formation present in that galaxy. When compared to the star formation rates (SFRs) of non-pair galaxies matched in mass, redshift, and local environment, we find that the star formation enhancement is weakly positively correlated (∼2.5σ) with H i gas fraction. In order to help understand the physical mechanisms driving this weak correlation, we also present results from a small suite of binary galaxy merger simulations with varying gas fractions. The simulated galaxies indicate that larger initial gas fractions are associated with lower levels of interaction-triggered star formation (relative to an identical galaxy in isolation), but also show that high gas fraction galaxies have higher absolute SFRs prior to an interaction. We show that when interaction-driven SFR enhancements are calculated relative to a galaxy with an average gas fraction for its stellar mass, the relationship between SFR and initial gas fraction dominates over the SFR enhancements driven by the interaction. Simulated galaxy interactions that are matched in stellar mass but not in gas fraction, like our VLA sample, yield the same general positive correlation between SFR enhancement and gas fraction that we observe

Factors Associated with Transgender and Gender Diverse People's Experience of Sexual Coercion, and Help-Seeking and Wellbeing Among Victims/Survivors: Results of the First Australian Trans and Gender Diverse Sexual Health Survey

Purpose: Our study examined factors associated with transgender and gender diverse (“trans”) people's experience of sexual coercion, as well as the factors associated with help-seeking and wellbeing among victims/survivors. Methods: We analyzed cross-sectional data from the first Australian Trans and Gender Diverse Sexual Health Survey, conducted in 2018. Logistic regressions were undertaken to identify factors associated with sexual coercion, help-seeking, and wellbeing. Results: Of the sample of 1448 participants, 53.4% had been sexually coerced, which was associated with older age, Aboriginal or Torres Strait Islander descent, nonbinary gender, being presumed female gender at birth, currently living publicly some or all the time as their affirmed gender, having regular sex, and use of drugs to enhance or alter sexual experiences. Protective factors included having a higher income and access to gender affirming care. Help-seeking was reported among 49.5% of victims/survivors and was associated with having more trans friends. Wellbeing among victims/survivors was associated with being older, residing in regional/remote areas, having higher levels of education and annual income, being presumed female gender at birth, having stronger satisfaction with one's sex life, and good health care access. Wellbeing was not associated with help-seeking. Conclusion: Sexual coercion was prevalent among participants, but help-seeking behavior was low. Protective factors identified underscore the importance of socioeconomic supports, access to health and gender affirming care, and peers. Accessible peer-led and culturally safe preventive and trauma-focused supports should also be considered for trans people who experience sexual coercion

Biosynthesis of phenolic tetrahydroisoquinoline alkaloids of peyote

Data are presented supporting a proposed pathway of biosynthesis of the phenolic tetrahydroisoquinoline alkaloids of peyote from dopamine. It is suggested that meta-O-methylation of dopamine, hydroxylation in the 5-position, para-O-methylation and finally cyclizations yield anhalamine, anhalidine, anhalonidine and pellotine.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32728/1/0000096.pd