1,051 research outputs found
James Bond: international man of gastronomy
This article is concerned with the representation of food and drink in Ian Fleming’s James Bond novels. In particular, it examines how the author uses Bond’s culinary knowledge and habits of consumption as an important constituent of his hero’s character. Similarly, the food choices of other characters, notably villains, are shown to be linked, by Fleming, to core aspects of their identity − principally their ethnicity. Bond’s impulse to observe and classify, very much in evidence in the novels’ food sequences, is examined in terms of the texts’ construction of Bond as a skilled identifier of signs
On X-Ray Optical Depth in the Coronae of Active Stars
We have investigated the optical thickness of the coronal plasma through the analysis of high-resolution X-ray spectra of a large sample of active stars observed with the High Energy Transmission Grating Spectrometer on Chandra. In particular, we probed for the presence of significant resonant scattering in the strong Lyman series lines arising from hydrogen-like oxygen and neon ions. The active RS CVn-type binaries II Peg and IM Peg and the single M dwarf EV Lac show significant optical depth. For these active coronae, the Lyα/Lyβ ratios are significantly depleted as compared with theoretical predictions and with the same ratios observed in similar active stars. Interpreting these decrements in terms of resonance scattering of line photons out of the line of sight, we are able to derive an estimate for the typical size of coronal structures, and from these we also derive estimates of coronal filling factors. For all three sources we find that both the photon path length as a fraction of the stellar radius and the implied surface filling factors are very small and amount to a few percent at most. The measured Lyα/Lyβ ratios are in good agreement with APED theoretical predictions, thus indicating negligible optical depth, for the other sources in our sample. We discuss the implications for coronal structuring and heating flux requirements. For the stellar sample as a whole, the data suggest increasing quenching of Lyα relative to Lyβ as a function of both LX/Lbol and the density-sensitive Mg XI forbidden-to-intercombination line ratio, as might generally be expected
Development of a submerged aquatic vegetation growth model in the coupled ocean-atmosphere-wave-sediment transport (COAWST v3.4) model
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Kalra, T. S., Ganju, N. K., & Testa, J. M. Development of a submerged aquatic vegetation growth model in the coupled ocean-atmosphere-wave-sediment transport (COAWST v3.4) model. Geoscientific Model Development, 13(11), (2020): 5211-5228, doi:10.5194/gmd-13-5211-2020.The coupled biophysical interactions between submerged aquatic vegetation (SAV), hydrodynamics (currents and waves), sediment dynamics, and nutrient cycling have long been of interest in estuarine environments. Recent observational studies have addressed feedbacks between SAV meadows and their role in modifying current velocity, sedimentation, and nutrient cycling. To represent these dynamic processes in a numerical model, the presence of SAV and its effect on hydrodynamics (currents and waves) and sediment dynamics was incorporated into the open-source Coupled Ocean–Atmosphere–Wave–Sediment Transport (COAWST) model. In this study, we extend the COAWST modeling framework to account for dynamic changes of SAV and associated epiphyte biomass. Modeled SAV biomass is represented as a function of temperature, light, and nutrient availability. The modeled SAV community exchanges nutrients, detritus, dissolved inorganic carbon, and dissolved oxygen with the water-column biogeochemistry model. The dynamic simulation of SAV biomass allows the plants to both respond to and cause changes in the water column and sediment bed properties, hydrodynamics, and sediment transport (i.e., a two-way feedback). We demonstrate the behavior of these modeled processes through application to an idealized domain and then apply the model to a eutrophic harbor where SAV dieback is a result of anthropogenic nitrate loading and eutrophication. These cases demonstrate an advance in the deterministic modeling of coupled biophysical processes and will further our understanding of future ecosystem change.This is University of Maryland Center for Environmental Contribution no. 5909
Selective anticancer activity of a hexapeptide with sequence homology to a non-kinase domain of Cyclin Dependent Kinase 4
Background: cyclin-dependent kinases 2, 4 and 6 (Cdk2, Cdk4, Cdk6) are closely structurally homologous proteins which are classically understood to control the transition from the G1 to the S-phases of the cell cycle by combining with their appropriate cyclin D or cyclin E partners to form kinase-active holoenzymes. Deregulation of Cdk4 is widespread in human cancer, CDK4 gene knockout is highly protective against chemical and oncogene-mediated epithelial carcinogenesis, despite the continued presence of CDK2 and CDK6; and overexpresssion of Cdk4 promotes skin carcinogenesis. Surprisingly, however, Cdk4 kinase inhibitors have not yet fulfilled their expectation as 'blockbuster' anticancer agents. Resistance to inhibition of Cdk4 kinase in some cases could potentially be due to a non-kinase activity, as recently reported with epidermal growth factor receptor. Results: a search for a potential functional site of non-kinase activity present in Cdk4 but not Cdk2 or Cdk6 revealed a previously-unidentified loop on the outside of the C'-terminal non-kinase domain of Cdk4, containing a central amino-acid sequence, Pro-Arg-Gly-Pro-Arg-Pro (PRGPRP). An isolated hexapeptide with this sequence and its cyclic amphiphilic congeners are selectively lethal at high doses to a wide range of human cancer cell lines whilst sparing normal diploid keratinocytes and fibroblasts. Treated cancer cells do not exhibit the wide variability of dose response typically seen with other anticancer agents. Cancer cell killing by PRGPRP, in a cyclic amphiphilic cassette, requires cells to be in cycle but does not perturb cell cycle distribution and is accompanied by altered relative Cdk4/Cdk1 expression and selective decrease in ATP levels. Morphological features of apoptosis are absent and cancer cell death does not appear to involve autophagy. Conclusion: these findings suggest a potential new paradigm for the development of broad-spectrum cancer specific therapeutics with a companion diagnostic biomarker and a putative functional site for kinase-unrelated activities of Cdk4
Advances in Our Understanding of Pelagic–Benthic Coupling
We synthesized our present understanding of pelagic–benthic (P–B) interactions in the northern Adriatic Sea (NAS) and Chesapeake Bay (CB) in a comparative analysis that builds on a prior comparison. We focus on primary production (PP) in the water column and benthos, the sedimentation and horizontal transport of particlulate organic matter (POM), and biogeochemical responses of the benthic community to sedimentation. Phytoplankton net PP (NPP) remains higher in CB (five times that in NAS) and rates of benthic respiration appear greater in CB (three times that in NAS). A lower fraction of phytoplankton NPP plus riverine inputs of POM is deposited to sediments in the NAS (23%) compared to CB (83%). A high percentage of organic matter inputs are respired by plankton and exported in the NAS and CB, and benthic communities respired a similar percentage of POM (86% in the NAS, 92% in CB). Net release of regenerated N from the benthos (0.2–0.3 mol N m−2 year−1) is also similar in both systems. At 0.53 mol N m−2 year−1, rates of benthic denitrification are higher in CB than in the NAS (0.3 mol N m−2 year−1), and the NAS appears to bury similar fractions of deposited N and P (N: 23% in NAS, 19% in CB; P: 50% in NAS, 45% in CB). To address the impacts of future climate‐driven warming and acceleration of the water cycle, we recommend a return to sustained monitoring combined with numerical simulations to allow improved understanding and predictions of changes in P–B interactions
Expanding the synthesis of distributed memory implementations
Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2015.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (page 63).In this thesis, I expanded the programming model implemented by the Sketch language to supplement its distributed memory parallelism with shared memory parallelism that uses the popular fork-join model. The primary contribution of this thesis is the means by which the code is assured to be free of race conditions. Sketch uses constraint satisfaction analysis to ensure it synthesizes code the functions properly for all inputs, and I demonstrate how assertions can be generated and inserted into the analysis to guarantee freedom from race conditions. This expanded programming model is then evaluated using test cases to ensure correct operation and benchmarks to examine overall performance.by Jeremy Edward Sharpe.M. Eng
An interpreter for a novice-oriented programming language with runtime macros
Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (pages 77-78).In this thesis, we present the design and implementation of a new novice-oriented programming language with automatically hygienic runtime macros, as well as an interpreter framework for creating such languages. The language is intended to be used as a pedagogical tool for introducing basic programming concepts to introductory programming students. We designed it to have a simple notional machine and to be similar to other modern languages in order to ease a student's transition into other programming languages.by Jeremy Daniel Kaplan.M. Eng
A low power display driver with simultaneous image transformation
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (leaves 70-73).In this thesis, I designed, implemented, and evaluated the energy consumption of a system that uses a liquid crystal display to perform a one-dimensional transform. The RMS response of the liquid crystal elements themselves were exploited to perform a matrix multiplication (image transformation) over a single frame period. This image transformation was used as the last step of the decompression process in an image processing system. The system was implemented first in Matlab, then as a printed circuit board, and finally as an integrated circuit. While the initial Matlab and printed circuit board implementations looked promising, a number of practical considerations arose during the integrated circuit design that ultimately resulted in moderate performance: 14.3% energy savings.by Jeremy Zaks Walker.M.Eng
Interactive debugger with reversible state
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Thesis: M. Eng. in Computer Science and Engineering, Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2019Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (page 43).This thesis describes PSI (Python Semantic Investigator), a program designed to help students explore their code by allowing them to see the state of their program at any step along its execution. PSI enables them to move forwards or backwards freely along the timeline of their program. It also enables them to designate variable names or object IDs and jump back to the last time such a variable or object was modified. Doing so is intended to help novice students learn to debug more effectively.by Jeremy Theard Wright.M. Eng. in Computer Science and EngineeringM.Eng.inComputerScienceandEngineering Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Scienc
- …
