Optimum transfer to Mars via Venus

Thrust maneuver at Venus for optimum Earth-Mars rendezvous trajectory in flyby missio

Nest site selection and differential defense responses based on nest substrate in Neotropical termites (Nasutitermes spp.)

Nest site selection in a variety of species can be impacted by the assessment of predation risk. Predation risk can be evaluated by factors such as nest height, concealment, and substrate type. With the assumption that predation risk varies among substrate types, Nasutitermes spp. termites were predicted to non-randomly select nest sites based on substrate type and to display differential defense response as a function of substrate. If given vibratory cues prior to nest breach, Nasutitermes spp. termites were predicted to react to the breach more quickly or with more soldiers. Seventy five nests were surveyed at the Palo Verde Biological Station to record nest substrate type, nest area, nest coverage by vegetation, and potential nest sites within a 10m radius. Upon nest breach, the time to the first soldier’s arrival and the subsequent number of soldiers that flocked to the disturbance site were recorded for each active nest. Nasutitermes spp. nest site selection reflected the availability of accessible substrate types rather than reflecting a preference for one type. There was no change in defense response in relation to substrate type or the presence of advance vibratory cues. Nasutitermes spp. nest site selection is not influenced by substrate type, suggesting that substrate types may not experience differential predation risk

Standup Comedy as Artistic Expression: Lenny Bruce, the 1950s, and American Humor

STANDUP COMEDY AS ARTISTIC EXPRESSION: LENNY BRUCE, THE 1950s, AND AMERICAN HUMOR by ANDREA SHANNON PRUSSING-HOLLOWELL Under the Direction of Michelle Brattain ABSTRACT Despite the common memory of the 1950s being an intolerant, conformist decade, many “underground” cultures developed and thrived in response to America’s homogenized national culture. Lenny Bruce was immersed within these cultures, using standup comedy as a vehicle to express his and his audiences’ disillusionment. This thesis aims to place Bruce back in his original context of the 1950s in order to understand why the 1960s youth embraced him as their own. By examining the 1950s underground, the history of standup comedy, and Bruce’s comedy, the 1950s youth emerge as an important precursor to the 1960s social movements, and Bruce’s martyrdom as a free speech crusader becomes more understandable and tragic. INDEX WORDS: Lenny Bruce, Standup comedy, 1950s, Humor, Beats, Obscenity, Free speech, Satir

What do the orbital motions of the outer planets of the Solar System tell us about the Pioneer anomaly?

In this paper we investigate the effects that an anomalous acceleration as that experienced by the Pioneer spacecraft after they passed the 20 AU threshold would induce on the orbital motions of the Solar System planets placed at heliocentric distances of 20 AU or larger as Uranus, Neptune and Pluto. It turns out that such an acceleration, with a magnitude of 8.74\times 10^-10 m s^-2, would affect their orbits with secular and short-period signals large enough to be detected according to the latest published results by E.V. Pitjeva, even by considering errors up to 30 times larger than those released. The absence of such anomalous signatures in the latest data rules out the possibility that in the region 20-40 AU of the Solar System an anomalous force field inducing a constant and radial acceleration with those characteristics affects the motion of the major planets.Comment: Latex2e, 19 pages, 3 tables, 10 figures, 18 references. Authorship changed; new figures added for a direct comparison with the observable quantities. Accepted for publication in New Astronom

A PRELIMINARY STUDY OF THE INFLUENCE OF BREEDING AREA DENSITY ON SANDHILL CRANE HABITAT SELECTION IN SOUTH-CENTRAL WISCONSIN

We hypothesized that territorial sandhill cranes (Grus canadensis) in densely populated breeding areas occupy smaller home ranges that are richer in optimal habitat than those in less densely populated breeding areas. We analyzed satellite telemetry data collected from 2012 to 2016 for 3 and 2 sandhill cranes from dense and less dense breeding areas, respectively. Tracked sandhill cranes in a dense breeding area tended to have smaller home ranges (0.37-14.25 km2) with higher concentrations of wetlands (27%) and row crops (40%) than tracked sandhill cranes in the less dense breeding area (8.80-48.81 km2, 14% wetlands and 26% row crops). Studies on variation of breeding season habitat use will help to better understand the areas where breeding sandhill cranes are likely to congregate and can inform management and harvest decisions for sandhill cranes

NASA/USRA University advanced design program

The participation of the University of Illinois at Urbana-Champaign in the NASA/USRA University Advanced Design Program for the 1988 to 1989 academic year is reviewed. The University's design project was the Logistics Resupply and Emergency Crew Return System for Space Station Freedom. Sixty-one students divided into eight groups, participated in the spring 1989 semester. A presentation prepared by three students and a graduate teaching assistant for the program's summer conference summarized the project results. Teamed with the NASA Marshall Space Flight Center (MSFC), the University received support in the form of remote telecon lectures, reference material, and previously acquired applications software. In addition, a graduate teaching assistant was awarded a summer 1989 internship at MSFC

An investigation of surface shape effects on near-field radiative transfer

It has been shown that the energy exchange between two objects can be greatly enhanced when the separation between the objects is on the order of the wavelength of thermal emission. The earliest theoretical and computational work focused on simple planar and spherical geometries, or they resorted to approximations that separated the object to outside of the thermal wavelength $\lambda_T = hc/(k_BT)$. Since those original works, the study of near-field energy exchange has expanded to object shapes that can be described by a separable coordinate system using a spectral expansion of the dyadic Green function of the system. The boundary element method has also been used to study arbitrary shapes in thermal equilibrium. Application of these new expansion methods to general shapes out of thermal equilibrium will facilitate in the optimization of nanoscale structures. A three step process is used to investigate the effects of object shape on the total and directionality of the energy exchange between objects. First, a general expression for the energy flux between the objects will be formulated. Second, a computational method to evaluate the expression will be implemented. Finally, the effects of varying the surface geometry will be explored. The computational results demonstrate that the total energy exchange between two bodies is influenced by the surface shape of the objects even when the surface areas are held constant. While the primary increase over the classical blackbody energy exchange $\sigma T^4 A$ is primarily governed by separation of the surfaces, we show that the view factors from classical far-field radiative transfer can be used to predict the change in the total energy exchange from a reference configuration at the same separation when the surface area of the two objects is comparable. Additionally, we demonstrate that the spatial distribution of the energy exchange can be localized into small spatial region with a peak value increased over \SI{30}{\percent} by using two objects with dramatically different projected areas.Ph.D

QYMSYM: A GPU-Accelerated Hybrid Symplectic Integrator That Permits Close Encounters

We describe a parallel hybrid symplectic integrator for planetary system integration that runs on a graphics processing unit (GPU). The integrator identifies close approaches between particles and switches from symplectic to Hermite algorithms for particles that require higher resolution integrations. The integrator is approximately as accurate as other hybrid symplectic integrators but is GPU accelerated.Comment: 17 pages, 2 figure

Discrete Routh Reduction

This paper develops the theory of abelian Routh reduction for discrete mechanical systems and applies it to the variational integration of mechanical systems with abelian symmetry. The reduction of variational Runge-Kutta discretizations is considered, as well as the extent to which symmetry reduction and discretization commute. These reduced methods allow the direct simulation of dynamical features such as relative equilibria and relative periodic orbits that can be obscured or difficult to identify in the unreduced dynamics. The methods are demonstrated for the dynamics of an Earth orbiting satellite with a non-spherical $J_2$ correction, as well as the double spherical pendulum. The $J_2$ problem is interesting because in the unreduced picture, geometric phases inherent in the model and those due to numerical discretization can be hard to distinguish, but this issue does not appear in the reduced algorithm, where one can directly observe interesting dynamical structures in the reduced phase space (the cotangent bundle of shape space), in which the geometric phases have been removed. The main feature of the double spherical pendulum example is that it has a nontrivial magnetic term in its reduced symplectic form. Our method is still efficient as it can directly handle the essential non-canonical nature of the symplectic structure. In contrast, a traditional symplectic method for canonical systems could require repeated coordinate changes if one is evoking Darboux' theorem to transform the symplectic structure into canonical form, thereby incurring additional computational cost. Our method allows one to design reduced symplectic integrators in a natural way, despite the noncanonical nature of the symplectic structure.Comment: 24 pages, 7 figures, numerous minor improvements, references added, fixed typo

Nyssorhynchus dunhami: bionomics and natural infection by Plasmodium falciparum and P. vivax in the Peruvian Amazon.

BACKGROUND Nyssorhynchus dunhami, a member of the Nuneztovari Complex, has been collected in Brazil, Colombia, and Peru and described as zoophilic. Although to date Ny. dunhami has not been documented to be naturally infected by Plasmodium, it is frequently misidentified as other Oswaldoi subgroup species that are local or regional malaria vectors. OBJECTIVES The current study seeks to verify the morphological identification of Nuneztovari Complex species collected in the peri-Iquitos region of Amazonian Peru, to determine their Plasmodium infection status, and to describe ecological characteristics of their larval habitats. METHODS We collected Ny. nuneztovari s.l. adults in 2011-2012, and Ny. nuneztovari s.l. larvae and adults in 2016-2017. When possible, samples were identified molecularly using cytochrome c oxidase subunit I (COI) barcode sequencing. Adult Ny. nuneztovari s.l. from 2011-2012 were tested for Plasmodium using real-time PCR. Environmental characteristics associated with Ny. nuneztovari s.l. larvae-positive water bodies were evaluated. FINDINGS We collected 590 Ny. nuneztovari s.l. adults and 116 larvae from eight villages in peri-Iquitos. Of these, 191 adults and 111 larvae were identified by COI sequencing; all were Ny. dunhami. Three Ny. dunhami were infected with P. falciparum, and one with P. vivax, all collected from one village on one night. Ny. dunhami larvae were collected from natural and artificial water bodies, and their presence was positively associated with other Anophelinae larvae and amphibians, and negatively associated with people living within 250m. MAIN CONCLUSIONS Of Nuneztovari Complex species, we identified only Ny. dunhami across multiple years in eight peri-Iquitos localities. This study is, to our knowledge, the first report of natural infection of molecularly identified Ny. dunhami with Plasmodium. We advocate the use of molecular identification methods in this region to monitor Ny. dunhami and other putative secondary malaria vectors to more precisely evaluate their importance in malaria transmission