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Melbourne, FL, United States

The Florida Institute of Technology , is a private doctoral/research university in Melbourne, Florida. Florida Tech has five academic divisions with emphases on science, technology, engineering, and mathematics . The university's 130-acre primary, residential campus is located near the Melbourne International Airport and the Florida Tech Research Park; it is about 50 miles from the Kennedy Space Center and 75 miles from Orlando.The university was founded in 1958, as Brevard Engineering College, and has been known by its present name since 1966. In 2013, Florida Tech had an on-campus student body of 4,633, almost equally divided between graduate- and undergraduate-level students, with the plurality of them focusing their studies on engineering and the science. Across the 2012-2013 academic year, the university served approximately 16,000 students in total.Florida Tech is ranked among the best national doctoral-granting universities in the US and the world's best universities. The university has more than 60,000 alumni, including a National Teacher of the Year recipient, director of a NASA center, five astronauts, several astronaut candidates, the first female four-star general, two other four-star generals and nearly two dozen other generals, a 1992 Olympic medalist, a major league pitcher and others that serve as scientists, engineers, pilots, and managers in many high-technology enterprises. Wikipedia.

Batcheldor D.,Florida Institute of Technology
Astrophysical Journal Letters | Year: 2010

The observed relation between supermassive black hole (SMBH) mass (M •) and bulge stellar velocity dispersion (σ *) is described by log M• = α + βlog(σ*/200 km s-1). As this relation has important implications for models of galaxy and SMBH formation and evolution, there continues to be great interest in adding to the M• catalog. The "sphere of influence" (ri ) argument uses spatial resolution to exclude some M• estimates and pre-select additional galaxies for further SMBH studies. This Letter quantifies the effects of applying the ri argument to a population of galaxies and SMBHs that do not follow the M•-σ* relation. All galaxies with known values of σ*, closer than 100Mpc, are given a random M• and selected when ri is spatially resolved. These random SMBHs produce a M•- σ* relation of α = 8.3 ± 0.2, β = 4.0 ± 0.3, consistent with observed values. Consequently, future proposed M• estimates should not be justified solely on the basis of resolving ri . This Letter shows that the observed M •-σ* relation may simply be a result of available spatial resolution. However, it also implies that the observed M •-σ* relation defines an upper limit. This potentially provides valuable new insight into the processes of galaxy and SMBH formation and evolution. © 2010. The American Astronomical Society. All rights reserved. Source

Dwyer J.R.,Florida Institute of Technology
Journal of Geophysical Research: Space Physics | Year: 2012

As thunderclouds charge, the large-scale fields may approach the relativistic feedback threshold, above which the production of relativistic runaway electron avalanches becomes self-sustaining through the generation of backward propagating runaway positrons and backscattered X-rays. Positive intracloud (IC) lightning may force the large-scale electric fields inside thunderclouds above the relativistic feedback threshold, causing the number of runaway electrons, and the resulting X-ray and gamma ray emission, to grow exponentially, producing very large fluxes of energetic radiation. As the flux of runaway electrons increases, ionization eventually causes the electric field to discharge, bringing the field below the relativistic feedback threshold again and reducing the flux of runaway electrons. These processes are investigated with a new model that includes the production, propagation, diffusion, and avalanche multiplication of runaway electrons; the production and propagation of X-rays and gamma rays; and the production, propagation, and annihilation of runaway positrons. In this model, referred to as the relativistic feedback discharge model, the large-scale electric fields are calculated self-consistently from the charge motion of the drifting low-energy electrons and ions, produced from the ionization of air by the runaway electrons, including two- and three-body attachment and recombination. Simulation results show that when relativistic feedback is considered, bright gamma ray flashes are a natural consequence of upward +IC lightning propagating in large-scale thundercloud fields. Furthermore, these flashes have the same time structures, including both single and multiple pulses, intensities, angular distributions, current moments, and energy spectra as terrestrial gamma ray flashes, and produce large current moments that should be observable in radio waves. Copyright 2012 by the American Geophysical Union. Source

Liu N.,Florida Institute of Technology
Journal of Geophysical Research: Space Physics | Year: 2012

A two-dimensional fluid model with multiple charged species is developed for simulating the ionospheric responses to the lightning quasi-static electric (QE) field. In addition to electrons, the model takes into account four symbolic ion species and O- ions that are considered separately to investigate the role of the fast electron detachment process from O- in the ionospheric response. The modeling results of a sprite halo driven by positive cloud-to-ground lightning indicate that the halo can descend to lower altitude with much higher electron density behind its front when the O - detachment process is included. Electron density ahead of the halo front is not significantly reduced from the ambient value, so there is no attachment "hole" forming in that region that is commonly observed in previous modeling studies. The fast O- detachment process affects the dynamics of the halo by allowing the growth of electron density in the upper atmosphere under sub-breakdown condition, i.e., the electric field is smaller than the conventional breakdown threshold field. The implications of the results reported here to sprite streamer initiation include (1) low ambient electron density at sprite initiation altitude may be the only means to avoid avalanche overlapping before the avalanche-to-streamer transition; and (2) the large downward extent of the halo may offer an explanation for the initiation of sprites at the altitude as low as 65-70km, which was observed in previous studies. Source

Leonard A.C.,Florida Institute of Technology | Mechali M.,French National Center for Scientific Research
Cold Spring Harbor Perspectives in Medicine | Year: 2013

The onset of genomic DNA synthesis requires precise interactions of specialized initiator proteins with DNA at sites where the replication machinery can be loaded. These sites, defined as replication origins, are found at a few unique locations in all of the prokaryotic chromosomes examined so far. However, replication origins are dispersed among tens of thousands of loci in metazoan chromosomes, thereby raising questions regarding the role of specific nucleotide sequences and chromatin environment in origin selection and the mechanisms used by in itiatorsto recognize replication origins. Close examination of bacterial and archaeal replication origins reveals an array of DNA sequence motifs that position individual initiator protein molecules and promote initiator oligomerization on origin DNA. Conversely, the need for specific recognition sequences in eukaryotic replication origins is relaxed. In fact, the primary rule for origin selection appears to be flexibility, a feature that is modulated either by structural elements or by epigenetic mechanisms at least partly linked to the organization of the genome for gene expression. © 2013 Cold Spring Harbor Laboratory Press; all rights reserved. Source

van Woesik R.,Florida Institute of Technology
Proceedings. Biological sciences / The Royal Society | Year: 2012

The risk of global extinction of reef-building coral species is increasing. We evaluated extinction risk using a biological trait-based resiliency index that was compared with Caribbean extinction during the Plio-Pleistocene, and with extinction risk determined by the International Union for Conservation of Nature (IUCN). Through the Plio-Pleistocene, the Caribbean supported more diverse coral assemblages than today and shared considerable overlap with contemporary Indo-Pacific reefs. A clear association was found between extant Plio-Pleistocene coral genera and our positive resilience scores. Regional extinction in the past and vulnerability in the present suggests that Pocillopora, Stylophora and foliose Pavona are among the most susceptible taxa to local and regional isolation. These same taxa were among the most abundant corals in the Caribbean Pliocene. Therefore, a widespread distribution did not equate with immunity to regional extinction. The strong relationship between past and present vulnerability suggests that regional extinction events are trait-based and not merely random episodes. We found several inconsistencies between our data and the IUCN scores, which suggest a need to critically re-examine what constitutes coral vulnerability. Source

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