1,053 research outputs found
Making a rainbow workstation for a chemistry lab
Chemical kinetics is the study of how quickly and by what means chemical reactions proceed. Some reactions are so fast and complicated that data must be taken very quickly and then lengthy calculations must be done to get results. Computers speed these studies greatly. The system to he described uses a DEC-Rainbow microcomputer as a terminal for a workstation. The system may collect 8k of buffered data at a rate of 1MHz and then upload the data to a VAX for analysis using the same Rainbow u a graphics terminal. The program for data analysis, called KinSim, will then accept the data and also other information about the chemical reactions in the same symbolic format that chemists use so that the analysis may be done. The analysis consists of simulating the chemical reactioll8 from the information provided and compare it with the experimental data that was collected earlier on the Rainbow
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Gathering Up the ‘Pieces of [His] Youth’: A Study of Tennessee Williams’ Non-Fiction
Tennessee Williams wrote almost daily for over forty years, leaving behind him a trove of
manuscripts that editors are only now beginning to discover. Previously unpublished work of his
has thus appeared almost yearly in journals and in book form since the mid-1990s, attesting to the
fact that Williams is enjoying a literary afterlife as fertile as the one he knew while he was still
alive. My research at Columbia University’s Rare Book & Manuscript Library (RBML) hopes to
contribute to prolonging that afterlife. During my research stay at the RBML this past August, I was able to examine many of Williams’s non-fiction manuscripts, in particular those related directly or indirectly to his Memoirs, published in 197
In Interview with American Playwright Mark SaFranko
Entretien avec l’auteur Mark SaFranko en résidence à Nancy dans le cadre du Projet ARIEL.Interview with Mark SaFranko, writer in residence in Nancy for the Projet ARIEL
Barkhausen Noise and Critical Scaling in the Demagnetization Curve
The demagnetization curve, or initial magnetization curve, is studied by
examining the embedded Barkhausen noise using the non-equilibrium, zero
temperature random-field Ising model. The demagnetization curve is found to
reflect the critical point seen as the system's disorder is changed. Critical
scaling is found for avalanche sizes and the size and number of spanning
avalanches. The critical exponents are derived from those related to the
saturation loop and subloops. Finally, the behavior in the presence of long
range demagnetizing fields is discussed. Results are presented for simulations
of up to one million spins.Comment: 4 pages, 4 figures, submitted to Physical Review Letter
Expanding the phenotypic associations of globular glial tau subtypes
AbstractIntroductionClinicopathologic correlation in non-Alzheimer's tauopathies is variable, despite refinement of pathologic diagnostic criteria. In the present study, the clinical and neuroimaging characteristics of globular glial tauopathy (GGT) were examined to determine whether subtyping according to consensus guidelines improves clinicopathologic correlation.MethodsConfirmed GGT cases (n = 11) were identified from 181 frontotemporal tauopathy cases. Clinical and neuroimaging details were collected, and cases sub-typed according to the consensus criteria for GGT diagnosis. Relationships between clinical syndrome and GGT subtype were investigated.ResultsIn total, 11 patients (seven males, four females, mean age = 67.3 +/− 10.6 years) with GGT were included. Most, but not all, presented with behavioral variant frontotemporal dementia, but none had amyotrophic lateral sclerosis. Subtyping of GGT proved to be difficult and did not improve clinicopathologic correlation.DiscussionSub-classification of GGT pathology may be difficult and did not improve clinicopathologic correlation. Better biomarkers of tau pathology are needed
Exact half-BPS Type IIB interface solutions I: Local solution and supersymmetric Janus
The complete Type IIB supergravity solutions with 16 supersymmetries are
obtained on the manifold with
symmetry in terms of two holomorphic
functions on a Riemann surface , which generally has a boundary. This
is achieved by reducing the BPS equations using the above symmetry
requirements, proving that all solutions of the BPS equations solve the full
Type IIB supergravity field equations, mapping the BPS equations onto a new
integrable system akin to the Liouville and Sine-Gordon theories, and mapping
this integrable system to a linear equation which can be solved exactly.
Amongst the infinite class of solutions, a non-singular Janus solution is
identified which provides the AdS/CFT dual of the maximally supersymmetric
Yang-Mills interface theory discovered recently. The construction of general
classes of globally non-singular solutions, including fully back-reacted and supersymmetric Janus doped with D5 and/or NS5 branes, is
deferred to a companion paper.Comment: LaTeX, 69 pages, 3 figures, v2: references adde
Low Speed, 2-D Rotor/Stator Active Noise Control at the Source Demonstration
Wake/blade-row interaction noise produced by the Annular Cascade Facility at Purdue University has been modeled using the LINFLO analysis. Actuator displacements needed for complete cancellation of the propagating acoustic response modes have been determined, along with the associated actuator power requirements. As an alternative, weighted least squares minimization of the total far-field sound power using individual actuators has also been examined. Attempts were made to translate the two-dimensional aerodynamic results into three-dimensional actuator requirements. The results lie near the limit of present actuator technology. In order to investigate the concept of noise control at the source for active rotor/stator noise control at the source, various techniques for embedding miniature actuators into vanes were examined. Numerous miniature speaker arrangements were tested and analyzed to determine their suitability as actuators for a demonstration test in the Annular Cascade Facility at Purdue. The best candidates demonstrated marginal performance. An alternative concept to using vane mounted speakers as control actuators was developed and tested. The concept uses compression drivers which are mounted externally to the stator vanes. Each compression driver is connected via a tube to an air cavity in the stator vane, from which the driver signal radiates into the working section of the experimental rig. The actual locations and dimensions of the actuators were used as input parameters for a LINFLO computational analysis of the actuator displacements required for complete cancellation of tones in the Purdue experimental rig. The actuators were designed and an arrangement determined which is compatible with the Purdue experimental rig and instrumentation. Experimental tests indicate that the actuators are capable of producing equivalent displacements greater than the requirements predicted by the LINFLO analysis. The acoustic output of the actuators was also found to be unaffected by the presence of air flow representative of the Purdue experimental rig. A test of the active noise control at the source concept for rotor/stator active noise control was demonstrated. This 2-D test demonstrated conclusively the simultaneous reduction of two acoustic modes. Reductions of over 10 dB were obtained over a wide operating range
Bilingualism, social cognition and executive functions:A tale of chickens and eggs
AbstractThe influence of bilingualism on cognitive functioning is currently a topic of intense scientific debate. The strongest evidence for a cognitive benefit of bilingualism has been demonstrated in executive functions. However, the causal direction of the relationship remains unclear: does learning other languages improve executive functions or are people with better executive abilities more likely to become bilingual?To address this, we examined 90 male participants of the Lothian Birth Cohort 1936; 26 were bilingual, 64 monolingual. All participants underwent an intelligence test at age 11 years and were assessed on a wide range of executive and social cognition tasks at age 74. The only notable differences between both groups were found for the Simon Effect (which indexes stimulus-response conflict resolution; β=−.518, p=0.025) and a trend effect for the Faux Pas task (a measure of complex theory of mind; ToM, β=0.432, p=0.060). Controlling for the influence of childhood intelligence, parental and own social class significantly attenuated the bilingual advantage on the Faux Pas test (β=0.058, p=0.816), whereas the Simon task advantage remained (β=−.589, p=0.049).We find some weak evidence that the relationship between bilingualism and cognitive functions may be selective and bi-directional. Pre-existing cognitive and social class differences from childhood may influence both ToM ability in older age and the likelihood of learning another language; yet, bilingualism does not appear to independently contribute to Faux Pas score. Conversely, learning a second language is related to better conflict processing, irrespective of initial childhood ability or social class
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