The assassination of Leon Trotsky: The proofs of Stalin\u27s guilt

https://stars.library.ucf.edu/prism/1597/thumbnail.jp

What is socialism?: Three lectures for workers

https://stars.library.ucf.edu/prism/1049/thumbnail.jp

Paired Storage Distributed Energy System Design for a Local Community Farm

This project considers the design of a renewable energy microgrid for a 19-acre community farm in San Luis Obispo, CA as the farm seeks to increase the magnitude of its electrical loads, and gain back-up electrical capability. The microgrid design will enable lower carbon emissions, reduce demand on the utility grid while saving on energy costs, and provide improved reliability and resiliency to the operator of the community farm. The eventual implementation of the design by a professional engineering entity will allow the community farm to expand its education program to include renewable energy as well as gain notoriety in the sustainability conscience community that City Farm relies on for donations. The design process will consist of 1) analysis of the farm’s existing electrical system and its loads, 2) a dive into State, local, and utility rules defining under what circumstances microgrids can be built interconnected to the grid, 3) analysis to estimate optimal component and resource sizing, and 4) recommending locations, components, protection and component settings for the smart distributed energy generation facility 5) analysis on safety, back up capacity, and financial feasibility of the design

A dearth of OH/IR stars in the Small Magellanic Cloud

We present the results of targeted observations and a survey of 1612-, 1665-, and 1667-MHz circumstellar OH maser emission from asymptotic giant branch (AGB) stars and red supergiants (RSGs) in the Small Magellanic Cloud (SMC), using the Parkes and Australia Telescope Compact Array radio telescopes. No clear OH maser emission has been detected in any of our observations targeting luminous, long-period, large-amplitude variable stars, which have been confirmed spectroscopically and photometrically to be mid- to late-M spectral type. These observations have probed 3 - 4 times deeper than any OH maser survey in the SMC. Using a bootstrapping method with LMC and Galactic OH/IR star samples and our SMC observation upper limits, we have calculated the likelihood of not detecting maser emission in any of the two sources considered to be the top maser candidates to be less than 0.05%, assuming a similar pumping mechanism as the LMC and Galactic OH/IR sources. We have performed a population comparison of the Magellanic Clouds and used Spitzer IRAC and MIPS photometry to confirm that we have observed all high luminosity SMC sources that are expected to exhibit maser emission. We suspect that, compared to the OH/IR stars in the Galaxy and LMC, the reduction in metallicity may curtail the dusty wind phase at the end of the evolution of the most massive cool stars. We also suspect that the conditions in the circumstellar envelope change beyond a simple scaling of abundances and wind speed with metallicity

Whither Evidentialist Reliabilism?

Evidentialism and Reliabilism are two of the main contemporary theories of epistemic justification. Some authors have thought that the theories are not incompatible with each other, and that a hybrid theory which incorporates elements of both should be taken into account. More recently, other authors have argued that the resulting theory is well- placed to deal with fine-grained doxastic attitudes (credences). In this paper I review the reasons for adopting this kind of hybrid theory, paying attention to the case of credences and the notion of probability involved in their treatment. I argue that the notion of probability in question can only be an epistemic (or evidential) kind of probability. I conclude that the resulting theory will be incompatible with Reliabilism in one important respect: it cannot deliver on the reductivist promise of Reliabilism. I also argue that attention to the justification of basic beliefs reveals limitations in the Evidentialist framework as well. The theory that results from the right combination of Evidentialism and Reliabilism, therefore, is neither Evidentialist nor Reliabilist

The contribution of Oxygen-Neon white dwarfs to the MACHO content of the Galactic Halo

The interpretation of microlensing results towards the Large Magellanic Cloud (LMC) still remains controversial. White dwarfs have been proposed to explain these results and, hence, to contribute significantly to the mass budget of our Galaxy. However, several constraints on the role played by regular carbon-oxygen white dwarfs exist. Massivewhite dwarfs are thought to be made of a mixture of oxygen and neon. Correspondingly, their cooling rate is larger than those of typical carbon-oxygen white dwarfs and they fade to invisibility in short timescales. Consequently, they constitute a good candidate for explaining the microlensing results. Here, we examine in detail this hypothesis by using the most recent and up-to-date cooling tracks for massive white dwarfs and a Monte Carlo simulator which takes into account the most relevant Galactic inputs. We find that oxygen-neon white dwarfs cannot account for a substantial fraction of the microlensing depth towards the LMC, independently of the adopted initial mass function, although some microlensing events could be due to oxygen--neon white dwarfs. The white dwarf population contributes at most a 5% to the mass of the Galactic halo.Comment: 10 pages, 4 figures. Accepted for publication in Astronomy & Astrophysic

Modeling dimethylsulphide production in the upper ocean

Dimethylsulphide (DMS) is produced by upper ocean ecosystems and emitted to the atmosphere, where it may have an important role in climate regulation. Several attempts to quantify the role of DMS in climate change have been undertaken in modeling studies. We examine a model of biogenic DMS production and describe its endogenous dynamics and sensitivities. We extend the model to develop a one-dimensional version that more accurately resolves the important processes of the mixed layer in determining the ecosystem dynamics. Comparisons of the results of the one-dimensional model with an empirical relationship that describes the global distribution of DMS, and also with vertical profiles of DMS in the upper ocean measured at the Bermuda Atlantic Time Series, suggest that the model represents the interaction between the biological and physical processes well on local and global scales. Our analysis of the model confirms its veracity and provides insights into the important processes determining DMS concentration in the oceans

An Investigation of Clinical Correlates of Lewy Bodies in Autopsy-Proven Alzheimer Disease

Background: Studies of patients meeting clinical and pathologic criteria for Alzheimer disease (AD) have not consistently found associations between the presence of Lewy bodies (LBs) at postmortem examination and a higher frequency during life of the clinical features of dementia with LBs. Objective: To evaluate the clinical correlates of LBs in patients with AD. Design and Methods: Fifty-one patients were diagnosed as having probable AD during life and met pathologic criteria for AD. Semiquantitative ratings for LBs were obtained in 4 brain regions: substantia nigra, cingulate, insular cortex, and hippocampus. The patients had been followed up semiannually for up to 9.9 years before death, and clinical features associated with dementia with LBs, including extrapyramidal signs and visual hallucinations, were assessed at each study visit. Logistic regression analyses determined whether patients who had LBs were more likely than those without LBs to express specific clinical signs during follow-up. Cox analyses determined whether patients with LBs developed clinical signs or died earlier. Generalized estimating equations were used to compare rates of cognitive or functional change. Results: Nineteen of the 51 patients had at least 1 LB in one of the studied regions. In no case was a significant relation noted between LBs and the presence of a measured clinical sign. No LB measure was associated with an increased risk of developing any of the evaluated clinical signs earlier in the disease. There was no association between the presence of LBs and more rapid mortality or more rapid disease progression. Conclusions: In patients diagnosed as having AD during life, we did not observe a relation of LBs noted during postmortem examination with the presence of any clinical feature that we assessed or with the rapidity of disease progression. The relation between LBs and specific clinical manifestations may be tenuous in these patients

Do motor control genes contribute to interindividual variability in decreased movement in patients with pain?

<p>Abstract</p> <p>Background</p> <p>Because excessive reduction in activities after back injury may impair recovery, it is important to understand and address the factors contributing to the variability in motor responses to pain. The current dominant theory is the "fear-avoidance model", in which the some patients' heightened fears of further injury cause them to avoid movement. We propose that in addition to psychological factors, neurochemical variants in the circuits controlling movement and their modification by pain may contribute to this variability. A systematic search of the motor research literature and genetic databases yielded a prioritized list of polymorphic motor control candidate genes. We demonstrate an analytic method that we applied to 14 of these genes in 290 patients with acute sciatica, whose reduction in movement was estimated by items from the Roland-Morris Disability Questionnaire.</p> <p>Results</p> <p>We genotyped a total of 121 single nucleotide polymorphisms (SNPs) in 14 of these genes, which code for the dopamine D2 receptor, GTP cyclohydrolase I, glycine receptor α1 subunit, GABA-A receptor α2 subunit, GABA-A receptor β1 subunit, α-adrenergic 1C, 2A, and 2C receptors, serotonin 1A and 2A receptors, cannabinoid CB-1 receptor, M1 muscarinic receptor, and the tyrosine hydroxylase, and tachykinin precursor-1 molecules. No SNP showed a significant association with the movement score after a Bonferroni correction for the 14 genes tested. Haplotype analysis of one of the blocks in the GABA-A receptor β1 subunit showed that a haplotype of 11% frequency was associated with less limitation of movement at a nominal significance level value (p = 0.0025) almost strong enough to correct for testing 22 haplotype blocks.</p> <p>Conclusion</p> <p>If confirmed, the current results may suggest that a common haplotype in the GABA-A β1 subunit acts like an "endogenous muscle relaxant" in an individual with subacute sciatica. Similar methods might be applied a larger set of genes in animal models and human laboratory and clinical studies to understand the causes and prevention of pain-related reduction in movement.</p

Galactic Bulge Microlensing Optical Depth from EROS-2

We present a new EROS-2 measurement of the microlensing optical depth toward the Galactic Bulge. Light curves of $5.6\times 10^{6}$ clump-giant stars distributed over $66 \deg^2$ of the Bulge were monitored during seven Bulge seasons. 120 events were found with apparent amplifications greater than 1.6 and Einstein radius crossing times in the range 5 {\rm d}. This is the largest existing sample of clump-giant events and the first to include northern Galactic fields. In the Galactic latitude range 1.4\degr<|b|<7.0\degr, we find $\tau/10^{-6}=(1.62 \pm 0.23)\exp[-a(|b|-3 {\rm deg})]$ with $a=(0.43 \pm0.16)\deg^{-1}$. These results are in good agreement with our previous measurement, with recent measurements of the MACHO and OGLE-II groups, and with predictions of Bulge models.Comment: accepted A&A, minor revision