Under the Wing of a Creature of the Night

Magnificent in its sheer power and beauty, this owl wing has a wingspan of 18 inches and measures 10 inches from the shoulder bone to the secondary feathers. Wings such as the one displayed play a vital role in the lifestyle of owls and other hunting birds who fulfill their dietary requirements through stealthy foraging in the dark of the night. Being predatory animals, an owl depends upon its wings as a weapon, equipping it with an arsenal worthy of any hunter. Because of their composition of downy feathers, soft fringes, and comb-like primary feathers, these light appendages create less audible sound waves through air, giving an owl the advantage of nearly silent flight. [excerpt

Rocky Horror: A Study in Shadows and Flight

“Rocky Horror: A Study in Shadows and Flight” is a creative nonfiction piece that analyzes the infamous legacy left by the cult classic, The Rocky Horror Picture Show. As a first-year in college, the speaker strings together a series of vignettes from different encounters with the film in her life, from her first midnight showing to her first performance as Columbia in a live production. In a few pages, this piece examines the meaning of identity and freedom as the speaker works through repulsion, rebellion, and all things Rocky

Atomic and molecular matter fields in periodic potentials

This paper deals with the conversion between atoms and molecules in optical lattices. We show that in the absence of collisional interaction, the atomic and molecular components in different lattice wells combine into states with macroscopic condensate fractions, which can be observed as a strong diffraction signal, if the particles are abruptly released from the lattice. The condensate population, and the diffraction signal are governed not only by the mean number of atoms or molecules in each well, but by the precise amplitudes on state vector components with different numbers of particles. We discuss ways to control these amplitudes and to maximize the condensate fraction in the molecular formation process.Comment: Invited talk at 'Quantum Challenges', Falenty, Poland, Sep. 2003. Submitted to J. Mod. Op

Counting Components in the Lagrange Multiplier Formulation of Teleparallel Theories

We investigate the Lagrange multiplier formulation of teleparallel theories, including f(T) gravity, in which the connection is not set to zero a priori and compare it with the pure frame theory. We show explicitly that the two formulations are equivalent, in the sense that the dynamical equations have the same content. One consequence is that the manifestly local Lorentz invariant f(T) theory cannot be expected to be free of pathologies, which were previously found to plague f(T) gravity formulated in the usual pure frame approach.Comment: 6 pages, version accepted for publicatio

Traffic, urban growth and suburban sprawl

Cities are still getting bigger in the western world. Even though urbanpopulations are barely reproducing themselves and migration from thecountryside to the town has slowed to a trickle, the demand for more livingspace shows no sign of abating as cities continue to expand their bordersthrough suburban sprawl. The automobile, of course, makes this possiblebut we show no signs of moving to other forms of transport that mightenable our cities to become a little more compact. The problems of sprawlare pervasive. Besides congestion, time wasted, and the long term costs ofusing non-renewable energy, the lack of good social infrastructure inrapidly growing suburban areas together with the erosion of agriculturalland, often of high environmental quality, has focused the debate onwhether or not such forms of development are sustainable. In this paper,we begin by noting that suburban sprawl is an age-old phenomenon whichrepresents a fine balance between the forces that are pushing peopletogether in cities and those that are forcing them out. These lead todifferent types of sprawl in different places and at different times butwhatever the variety, there are costs to be borne. We briefly review these,noting how these affect suburban sprawl in Europe, and the efforts of theEuropean Commission to understand the problem. We conclude not with aplea that cities should be compacted and all automobile traffic removedbut that we should engage in policies for ?smart growth? such as thosebeing adopted in North America

Overexpression of an activated REL mutant enhances the transformed state of the human B-lymphoma BJAB cell line and alters its gene expression profile

The human REL proto-oncogene encodes a transcription factor in the nuclear factor (NF)-kappaB family. Overexpression of REL is acutely transforming in chicken lymphoid cells, but has not been shown to transform any mammalian lymphoid cell type. In this report, we show that overexpression of a highly transforming mutant of REL (RELDeltaTAD1) increases the oncogenic properties of the human B-cell lymphoma BJAB cell line, as shown by increased colony formation in soft agar, tumor formation in SCID (severe combined immunodeficient) mice, and adhesion. BJAB-RELDeltaTAD1 cells also show decreased activation of caspase in response to doxorubicin. BJAB-RELDeltaTAD1 cells have increased levels of active nuclear REL protein as determined by immunofluorescence, subcellular fractionation and electrophoretic mobility shift assay. Overexpression of RELDeltaTAD1 in BJAB cells has transformed the gene expression profile of BJAB cells from that of a germinal center B-cell subtype of diffuse large B-cell lymphoma (DLBCL) (GCB-DLBCL) to that of an activated B-cell subtype (ABC-DLBCL), as evidenced by increased expression of many ABC-defining mRNAs. Upregulated genes in BJAB-RELDeltaTAD1 cells include several NF-kappaB targets that encode proteins previously implicated in B-cell development or oncogenesis, including BCL2, IRF4, CD40 and VCAM1. The cell system we describe here may be valuable for further characterizing the molecular details of REL-induced lymphoma in humans.P42 ES007381 - NIEHS NIH HHS; R01 CA047763 - NCI NIH HHS; CA047763 - NCI NIH HHS; R01 CA047763-20 - NCI NIH HHS; P42 ES007381-140019 - NIEHS NIH HHS; 5 P42 ES07381 - NIEHS NIH HHS; P42 ES007381-150019 - NIEHS NIH HHS; R01 CA047763-19 - NCI NIH HH

Ranking Functions for Size-Change Termination II

Size-Change Termination is an increasingly-popular technique for verifying program termination. These termination proofs are deduced from an abstract representation of the program in the form of "size-change graphs". We present algorithms that, for certain classes of size-change graphs, deduce a global ranking function: an expression that ranks program states, and decreases on every transition. A ranking function serves as a witness for a termination proof, and is therefore interesting for program certification. The particular form of the ranking expressions that represent SCT termination proofs sheds light on the scope of the proof method. The complexity of the expressions is also interesting, both practicaly and theoretically. While deducing ranking functions from size-change graphs has already been shown possible, the constructions in this paper are simpler and more transparent than previously known. They improve the upper bound on the size of the ranking expression from triply exponential down to singly exponential (for certain classes of instances). We claim that this result is, in some sense, optimal. To this end, we introduce a framework for lower bounds on the complexity of ranking expressions and prove exponential lower bounds.Comment: 29 pages