16,935 research outputs found
Types of absences allowed teachers without loss of pay in Massachusetts
Thesis (Ed.M.)--Boston Universit
Multifractal dimensions for all moments for certain critical random matrix ensembles in the strong multifractality regime
We construct perturbation series for the q-th moment of eigenfunctions of
various critical random matrix ensembles in the strong multifractality regime
close to localization. Contrary to previous investigations, our results are
valid in the region q<1/2. Our findings allow to verify, at first leading
orders in the strong multifractality limit, the symmetry relation for anomalous
fractal dimensions Delta(q)=Delta(1-q), recently conjectured for critical
models where an analogue of the metal-insulator transition takes place. It is
known that this relation is verified at leading order in the weak
multifractality regime. Our results thus indicate that this symmetry holds in
both limits of small and large coupling constant. For general values of the
coupling constant we present careful numerical verifications of this symmetry
relation for different critical random matrix ensembles. We also present an
example of a system closely related to one of these critical ensembles, but
where the symmetry relation, at least numerically, is not fulfilled.Comment: 12 pages, 12 figure
What Has Mattered to Economics Since 1970
We compile the list of articles published in major refereed economics journals during the last 35 years that have received more than 500 citations. We document major shifts in the mode of contribution and in the importance of different sub-fields: Theory loses out to empirical work, and micro and macro give way to growth and development in the 1990s. While we do not witness any decline in the primacy of production in the United States over the period, the concentration of institutions within the U.S. hosting and training authors of the highly-cited articles has declined substantially.
Seasonal reproduction in a fluctuating energy environment: Insolation-driven synchronized broadcast spawning in corals
*Background/Question/Methods:* Colonies of spawning corals reproduce in mass-spawning events, in which polyps within each colony release sperm and eggs for fertilization in the water column, with fertilization occurring only between gametes from different colonies. Participating colonies synchronize their gamete release to a window of a few hours once a year (for the species Acropora digitifera we study experimentally). This remarkable synchrony is essential for successful coral reproduction and thus, maintenance of the coral reef ecosystem that is currently under threat from local and global environmental effects such as pollution, global warming and ocean acidification. The mechanisms determining this tight synchrony in reproduction are not well understood, although several influences have been hypothesized and studied including lunar phase, solar insolation, and influences of temperature and tides. Moreover, most corals are in a symbiotic relationship with photosynthetic algae (Symbiodinium spp.) that live within the host tissue. Experiments supported by detailed bioenergetic modeling of the coral-algae symbiosis have shown that corals receive >90% of their energy needs from these symbionts. We develop a bioenergetic integrate-and-fire model in order to investigate whether annual insolation rhythms can entrain the gametogenetic cycles that produce mature gametes to the appropriate spawning season, since photosynthate is their primary source of energy. We solve the integrate-and-fire bioenergetic model numerically using the Fokker-Planck equation and use analytical tools such as rotation number to study entrainment.

*Results/Conclusions:* In the presence of short-term fluctuations in the energy input, our model shows that a feedback regulatory mechanism is required to achieve coherence of spawning times to within one lunar cycle, in order for subsequent cues such as lunar and diurnal light cycles to unambiguously determine the “correct” night of spawning. Entrainment to the annual insolation cycle is by itself not sufficient to produce the observed coherence in spawning. The feedback mechanism can also provide robustness against population heterogeneity due to genetic and environmental effects. We also discuss how such bioenergetic, stochastic, integrate-and-fire models are also more generally applicable: for example to aquatic insect emergence, synchrony in cell division and masting in trees
Preliminary design study of nuclear Brayton cycle/Heat Exchanger and Duct Assembly /HXDA/, phase 3 Topical report
Nuclear Brayton cycle heat exchanger and duct assembl
James Joyce and the Life Cycle: The Unfolded Picture
Joyce in his fiction ambitiously attempted to capture the whole of the human life cycle “from infancy through maturity to decay,” as he graphically phrases it in Ulysses (697). Beginning with the child’s earliest memories in A Portrait of an Artist as a Young Man and progressing through the vicissitudes of childhood, recorded in that novel along with the early stories in Dubliners, Joyce went on to analyze adolescence and early adulthood in the middle storiesin Dubliners, as well as in the bulk of A Portrait of an Artist as a Young Man. He then memorably depicted the middle mature years in his portrait of Leopoldand Molly Bloom in Ulysses. Finally, he pictured the evening of life in “The Dead” and its end and re-beginning in Finnegans Wake. Joyce’s works taken asa whole from A Portrait of the Artist as a Young Man and Dubliners through Ulysses and Exiles to Finnegans Wake – embody Erik Erickson’s “meaningfulinterplay between beginning and end as well as some finite sense of summary and, possibly, a more active anticipation of dying.”Joyce in his fiction ambitiously attempted to capture the whole of the human life cycle “from infancy through maturity to decay,” as he graphically phrases it in Ulysses (697). Beginning with the child’s earliest memories in A Portrait of an Artist as a Young Man and progressing through the vicissitudes of childhood, recorded in that novel along with the early stories in Dubliners, Joyce went on to analyze adolescence and early adulthood in the middle storiesin Dubliners, as well as in the bulk of A Portrait of an Artist as a Young Man. He then memorably depicted the middle mature years in his portrait of Leopoldand Molly Bloom in Ulysses. Finally, he pictured the evening of life in “The Dead” and its end and re-beginning in Finnegans Wake. Joyce’s works taken asa whole from A Portrait of the Artist as a Young Man and Dubliners through Ulysses and Exiles to Finnegans Wake – embody Erik Erickson’s “meaningfulinterplay between beginning and end as well as some finite sense of summary and, possibly, a more active anticipation of dying.
Quantized Non-Abelian Monopoles on S^3
A possible electric-magnetic duality suggests that the confinement of
non-Abelian electric charges manifests itself as a perturbative quantum effect
for the dual magnetic charges. Motivated by this possibility, we study vacuum
fluctuations around a non-Abelian monopole-antimonopole pair treated as point
objects with charges g=\pm n/2 (n=1,2,...), and placed on the antipodes of a
three sphere of radius R. We explicitly find all the fluctuation modes by
linearizing and solving the Yang-Mills equations about this background field on
a three sphere. We recover, generalize and extend earlier results, including
those on the stability analysis of non-Abelian magnetic monopoles. We find that
for g \ge 1 monopoles there is an unstable mode that tends to squeeze magnetic
flux in the angular directions. We sum the vacuum energy contributions of the
fluctuation modes for the g=1/2 case and find oscillatory dependence on the
cutoff scale. Subject to certain assumptions, we find that the contribution of
the fluctuation modes to the quantum zero point energy behaves as -R^{-2/3} and
hence decays more slowly than the classical -R^{-1} Coulomb potential for large
R. However, this correction to the zero point energy does not agree with the
linear growth expected if the monopoles are confined.Comment: 18 pages, 5 figures. Minor changes, reference list update
Sports Data Science Job Requirements
Data science is an extremely fast growing field in which job opportunities are opening in every industry related to data science. Within the data science field is the sports data science industry which has it\u27s own requirements and specificities that may not be present in other industries. In this paper, research is done using multiple job posting websites such as LinkedIn, Indeed, Sportstek jobs, and TeamworkOnline to explore the job descriptions of many different sports data science jobs. These job descriptions are then examined using Python coding to find the frequencies of specific data science skills in the various job postings to see which skills are most important for aspiring sports data scientists to learn
Death and the Playwright:Chris Lee’s The Electrocution of Children (1998) and The Map Maker’s Sorrow (1999)
The award-winning Irish playwright Chris Lee’s The Electrocution of Children (1998) was produced at the Peacock Theatre in 1998 while The Map Maker’s Sorrow became the Abbey entry in the 1999 Dublin Theatre Festival. The Electrocution of Children, an intellectually ambitious play depicts a world in which people have forgotten how precious the gift of life is, and how fragile human beings are. Characters in the play squander opportunities to be creative, turn their backs on relationships, fail in their attempts to communicate, and prey upon one another. Like the characters in Alfred Jarry’s Ubu Roi (1896), those in Lee’s play often appear to be wayward children who fail utterly to follow any rules of logic or propriety. The play itself moves sequentially through a series of scenes drawn from the debris of lives and the isolation of relationships. In contrast, The Map Maker’s Sorrow begins abruptly and confusingly with the suicide of a character the audience has not met and, therefore, does not know and then proceeds through no clear development to a harmonious end. (The play’s structure reflects Lee’s use of a map’s “simultaneous spatial logic” [40]). At the very beginning of the play, the audience finds itself in a position similar to that of the bereaved family in the play or that of any survivors who find a member of their family dead by his or her own hand. Suicide, like Lee’s opening scene, declares the strangeness of the other that the play then explores.The award-winning Irish playwright Chris Lee’s The Electrocution of Children (1998) was produced at the Peacock Theatre in 1998 while The Map Maker’s Sorrow became the Abbey entry in the 1999 Dublin Theatre Festival. The Electrocution of Children, an intellectually ambitious play depicts a world in which people have forgotten how precious the gift of life is, and how fragile human beings are. Characters in the play squander opportunities to be creative, turn their backs on relationships, fail in their attempts to communicate, and prey upon one another. Like the characters in Alfred Jarry’s Ubu Roi (1896), those in Lee’s play often appear to be wayward children who fail utterly to follow any rules of logic or propriety. The play itself moves sequentially through a series of scenes drawn from the debris of lives and the isolation of relationships. In contrast, The Map Maker’s Sorrow begins abruptly and confusingly with the suicide of a character the audience has not met and, therefore, does not know and then proceeds through no clear development to a harmonious end. (The play’s structure reflects Lee’s use of a map’s “simultaneous spatial logic” [40]). At the very beginning of the play, the audience finds itself in a position similar to that of the bereaved family in the play or that of any survivors who find a member of their family dead by his or her own hand. Suicide, like Lee’s opening scene, declares the strangeness of the other that the play then explores
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