520 research outputs found
The nu sub 2 band CHD3; ground state parameters for CHD3 from combination differences
The nu sub 2 fundamental band of CHD3, centered near 2143/cm, was recorded at a resolution of 0.015-0.25/cm. Analysis of ground state combination differences yielded well-determined values for the ground state molecular parameters for CHD3. These parameters were used in the determination of the alpha and beta molecular parameters for nu sub 2
A Logic for Non-Deterministic Parallel Abstract State Machines
We develop a logic which enables reasoning about single steps of
non-deterministic parallel Abstract State Machines (ASMs). Our logic builds
upon the unifying logic introduced by Nanchen and St\"ark for reasoning about
hierarchical (parallel) ASMs. Our main contribution to this regard is the
handling of non-determinism (both bounded and unbounded) within the logical
formalism. Moreover, we do this without sacrificing the completeness of the
logic for statements about single steps of non-deterministic parallel ASMs,
such as invariants of rules, consistency conditions for rules, or step-by-step
equivalence of rules.Comment: arXiv admin note: substantial text overlap with arXiv:1602.0748
The 12 micron band of ethane: A spectral catalog from 765 cm(-1) to 900 cm(-1)
The high resolution laboratory absorption spectrum of the 12 micro band of ethane gas is studied. The data were obtained using the McMath Solar Telescope 1 meter Fourier Transform interferometer at Kitt Peak National Observatory and tunable diode laser spectrometers at the University of Tennessee and NASA/Goddard Space Flight Center. Over 200 individual vibration rotation transitions were analyzed taking into account many higher order effects including torsional splitting. Line positions were reproduced to better than 0.001/cm. Both ground and upper state molecular constants were determined in the analysis. The experimental details, the analysis procedures and the results are addressed. A list of ethane transitions occurring near (14)CO2 laser lines needed for heterodyne searches for C2H6 in extraterrestrial sources is also included. A spectral catalog of the ethane nu sub g fundamental from 765/cm to 900/cm is provided. A high dispersion (1/cm 12 in.) plot of both the Kitt Peak interferometric data and a simulated spectrum with Doppler limited resolution, a table of over 8500 calculated transitions listed quantum number assignments, frequencies and intensities are provided
Deconvolving Instrumental and Intrinsic Broadening in Excited State X-ray Spectroscopies
Intrinsic and experimental mechanisms frequently lead to broadening of
spectral features in excited-state spectroscopies. For example, intrinsic
broadening occurs in x-ray absorption spectroscopy (XAS) measurements of heavy
elements where the core-hole lifetime is very short. On the other hand,
nonresonant x-ray Raman scattering (XRS) and other energy loss measurements are
more limited by instrumental resolution. Here, we demonstrate that the
Richardson-Lucy (RL) iterative algorithm provides a robust method for
deconvolving instrumental and intrinsic resolutions from typical XAS and XRS
data. For the K-edge XAS of Ag, we find nearly complete removal of ~9.3 eV FWHM
broadening from the combined effects of the short core-hole lifetime and
instrumental resolution. We are also able to remove nearly all instrumental
broadening in an XRS measurement of diamond, with the resulting improved
spectrum comparing favorably with prior soft x-ray XAS measurements. We present
a practical methodology for implementing the RL algorithm to these problems,
emphasizing the importance of testing for stability of the deconvolution
process against noise amplification, perturbations in the initial spectra, and
uncertainties in the core-hole lifetime.Comment: 35 pages, 13 figure
Growing Environmental Activists: Developing Environmental Agency and Engagement Through Children’s Fiction.
We explore how story has the potential to encourage environmental engagement and a sense of agency provided that critical discussion takes place. We illuminate this with reference to the philosophies of John Macmurray on personal agency and social relations; of John Dewey on the primacy of experience for philosophy; and of Paul Ricoeur on hermeneutics, dialogue, dialectics and narrative. We view the use of fiction for environmental understanding as hermeneutic, a form of conceptualising place which interprets experience and perception. The four writers for young people discussed are Ernest Thompson Seton, Kenneth Grahame, Michelle Paver and Philip Pullman. We develop the concept of critical dialogue, and link this to Crick's demand for active democratic citizenship. We illustrate the educational potential for environmental discussions based on literature leading to deeper understanding of place and environment, encouraging the belief in young people that they can be and become agents for change. We develop from Zimbardo the key concept of heroic resister to encourage young people to overcome peer pressure. We conclude with a call to develop a greater awareness of the potential of fiction for learning, and for writers to produce more focused stories engaging with environmental responsibility and activism
Pharmacokinetics of high-dose oral thiamine hydrochloride in healthy subjects
Background: High dose oral thiamine may have a role in treating diabetes, heart failure, and hypermetabolic states. The purpose of this study was to determine the pharmacokinetic profile of oral thiamine hydrochloride at 100 mg, 500 mg and 1500 mg doses in healthy subjects. Methods: This was a randomized, double-blind, single-dose, 4-way crossover study. Pharmacokinetic measures were calculated. Results: The and values increased nonlinearly between 100 mg and 1500 mg. The slope of the vs dose, as well as the vs dose, plots are steepest at the lowest thiamine doses. Conclusion: Our study demonstrates that high blood levels of thiamine can be achieved rapidly with oral thiamine hydrochloride. Thiamine is absorbed by both an active and nonsaturable passive process
Estrogen protects neuronal cells from amyloid beta-induced apoptosis via regulation of mitochondrial proteins and function
BACKGROUND: Neurodegeneration in Alzheimer's disease is associated with increased apoptosis and parallels increased levels of amyloid beta, which can induce neuronal apoptosis. Estrogen exposure prior to neurotoxic insult of hippocampal neurons promotes neuronal defence and survival against neurodegenerative insults including amyloid beta. Although all underlying molecular mechanisms of amyloid beta neurotoxicity remain undetermined, mitochondrial dysfunction, including altered calcium homeostasis and Bcl-2 expression, are involved in neurodegenerative vulnerability. RESULTS: In this study, we investigated the mechanism of 17β-estradiol-induced prevention of amyloid beta-induced apoptosis of rat hippocampal neuronal cultures. Estradiol treatment prior to amyloid beta exposure significantly reduced the number of apoptotic neurons and the associated rise in resting intracellular calcium levels. Amyloid beta exposure provoked down regulation of a key antiapoptotic protein, Bcl-2, and resulted in mitochondrial translocation of Bax, a protein known to promote cell death, and subsequent release of cytochrome c. E(2 )pretreatment inhibited the amyloid beta-induced decrease in Bcl-2 expression, translocation of Bax to the mitochondria and subsequent release of cytochrome c. Further implicating the mitochondria as a target of estradiol action, in vivo estradiol treatment enhanced the respiratory function of whole brain mitochondria. In addition, estradiol pretreatment protected isolated mitochondria against calcium-induced loss of respiratory function. CONCLUSION: Therefore, we propose that estradiol pretreatment protects against amyloid beta neurotoxicity by limiting mitochondrial dysfunction via activation of antiapoptotic mechanisms
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CORPORATE GOVERNANCE AND INVESTORS' PERCEPTIONS OF FOREIGN IPO VALUE: AN INSTITUTIONAL PERSPECTIVE
We build on sociology-grounded research on financial market behavior and suggest a “nested” legitimacy framework to explore U.S. investor perceptions of foreign IPO value. We draw on a fuzzy-set theoretic approach to demonstrate how different combinations of monitoring and incentive-based corporate governance mechanisms lead to the same level of investor valuations of firms. We also argue that institutional factors related to the minority shareholder protection strength in the foreign IPO’s home country represent a boundary condition that affects the number of governance mechanisms required to achieve U.S. investors’ high value perceptions. Our findings, drawn from a unique, hand-collected dataset of foreign IPOs in the U.S, contribute to the sociological perspective on comparative corporate governance and the inter-dependencies between organizations and institutions
2-Deoxy-D-Glucose Treatment Induces Ketogenesis, Sustains Mitochondrial Function, and Reduces Pathology in Female Mouse Model of Alzheimer's Disease
Previously, we demonstrated that mitochondrial bioenergetic deficits preceded Alzheimer's disease (AD) pathology in the female triple-transgenic AD (3xTgAD) mouse model. In parallel, 3xTgAD mice exhibited elevated expression of ketogenic markers, indicating a compensatory mechanism for energy production in brain. This compensatory response to generate an alternative fuel source was temporary and diminished with disease progression. To determine whether this compensatory alternative fuel system could be sustained, we investigated the impact of 2-deoxy-D-glucose (2-DG), a compound known to induce ketogenesis, on bioenergetic function and AD pathology burden in brain. 6-month-old female 3xTgAD mice were fed either a regular diet (AIN-93G) or a diet containing 0.04% 2-DG for 7 weeks. 2-DG diet significantly increased serum ketone body level and brain expression of enzymes required for ketone body metabolism. The 2-DG-induced maintenance of mitochondrial bioenergetics was paralleled by simultaneous reduction in oxidative stress. Further, 2-DG treated mice exhibited a significant reduction of both amyloid precursor protein (APP) and amyloid beta (Aβ) oligomers, which was paralleled by significantly increased α-secretase and decreased γ-secretase expression, indicating that 2-DG induced a shift towards a non-amyloidogenic pathway. In addition, 2-DG increased expression of genes involved in Aβ clearance pathways, degradation, sequestering, and transport. Concomitant with increased bioenergetic capacity and reduced β-amyloid burden, 2-DG significantly increased expression of neurotrophic growth factors, BDNF and NGF. Results of these analyses demonstrate that dietary 2-DG treatment increased ketogenesis and ketone metabolism, enhanced mitochondrial bioenergetic capacity, reduced β-amyloid generation and increased mechanisms of β-amyloid clearance. Further, these data link bioenergetic capacity with β-amyloid generation and demonstrate that β-amyloid burden was dynamic and reversible, as 2-DG reduced activation of the amyloidogenic pathway and increased mechanisms of β-amyloid clearance. Collectively, these data provide preclinical evidence for dietary 2-DG as a disease-modifying intervention to delay progression of bioenergetic deficits in brain and associated β-amyloid burden
Voices off: Stanley Milgram's cyranoids in historical context
This article revisits a forgotten, late project by the social psychologist Stanley Milgram: the ‘cyranoid’ studies he conducted from 1977 to 1984. These investigations, inspired by the play Cyrano de Bergerac, explored how individuals often fail to notice when others do not speak their own thoughts but instead relay messages from a hidden source. We situate these experiments amidst the intellectual, cultural, and political concerns of late Cold-War America and show how Milgram’s studies pulled together a variety of ideas, anxieties, and interests that were prevalent at that time and have returned in new guises since. In discussing the cyranoid project’s background and afterlife, we argue that its strikingly equivocal quality has lent itself to multiple reinterpretations by historians, psychologists, performers, artists and others. Our purpose is neither to champion Milgram’s work nor amplify the critiques already made of his methods. Rather it is consider the uncertain, allusive, and elusive aspects of the cyranoid project, and to seek to place that project ‘in context’, whilst asking where ‘context’ might end. We show how the experiments’ range of meanings, in different temporal registers, far exceeded the explanatory rubric that Milgram and his intellectual critics provided at that time; and ponder the risk for the historian of making anachronistic or teleological assumptions. In short, cyranoids, we argue, invite our open-ended exploration of ‘voices off stage’ in social and psychological relations, and offer a useful tool for thinking about historical context and the nature of historical interpretations
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