Multiphoton Imaging of Labeled Breast Cancer Cells to Quantify Intra and Extracellular Receptors

Every year 200,000 women in the United States are diagnosed with breast cancer. Of the cases diagnosed, 10% -15% are classified as triple negative breast cancer (TNBC) due to the absence of estrogen, progesterone, and HER-2/Neu receptors. This breast cancer sub-type is markedly more aggressive and twice as likely to develop in premenopausal women. TNBC is resistant to endocrine therapies and current targeted agents, making clinical need for the development of validated therapeutics for TNBC a pressing matter. To initiate drug development, the internalization of directly immunolabeled epidermal growth factor receptors (EGFR) in SK-BR-3 human breast adenocarcinoma cells was quantitated using live-cell multiphoton microscopy for 30 minutes over 5 minute intervals. EGFR targeting is of interest because its internalization triggers the signaling pathway that disrupts cell-cell adhesion and induces cell motility. The images acquired were processed using ImageJ and analyzed through line profiles. After measuring the full width half max at each time point of the 30-minute time series, it was determined that significant EGFR internalization did not occur

Time-frequency analysis of chaotic systems

We describe a method for analyzing the phase space structures of Hamiltonian systems. This method is based on a time-frequency decomposition of a trajectory using wavelets. The ridges of the time-frequency landscape of a trajectory, also called instantaneous frequencies, enable us to analyze the phase space structures. In particular, this method detects resonance trappings and transitions and allows a characterization of the notion of weak and strong chaos. We illustrate the method with the trajectories of the standard map and the hydrogen atom in crossed magnetic and elliptically polarized microwave fields.Comment: 36 pages, 18 figure

Transmitter switch for high-power microwave output

Combiner system can be used for combining output powers of two transmitters or for switching from one to the other. This can be done when pair of transmitters operate on same frequency and carriers are phase coherent as by excitation from single exciter

Researcher’s Reactions to Compelled Disclosure of Scientific Information

Demands placed on researchers by subpoenas for scientific information are not necessarily any greater than those placed on other third-party recipients of subpoenas

Coupling of transverse and longitudinal response in stiff polymers

The time-dependent transverse response of stiff polymers, represented as weakly-bending wormlike chains (WLCs), is well-understood on the linear level, where transverse degrees of freedom evolve independently from the longitudinal ones. We show that, beyond a characteristic time scale, the nonlinear coupling of transverse and longitudinal motion in an inextensible WLC significantly weakens the polymer response compared to the widely used linear response predictions. The corresponding feedback mechanism is rationalized by scaling arguments and quantified by a multiple scale approach that exploits an inherent separation of transverse and longitudinal correlation length scales. Crossover scaling laws and exact analytical and numerical solutions for characteristic response quantities are derived for different experimentally relevant setups. Our findings are applicable to cytoskeletal filaments as well as DNA under tension.Comment: 4 pages, 3 figures, 1 table; final versio

A Computational Procedure to Detect a New Type of High Dimensional Chaotic Saddle and its Application to the 3-D Hill's Problem

A computational procedure that allows the detection of a new type of high-dimensional chaotic saddle in Hamiltonian systems with three degrees of freedom is presented. The chaotic saddle is associated with a so-called normally hyperbolic invariant manifold (NHIM). The procedure allows to compute appropriate homoclinic orbits to the NHIM from which we can infer the existence a chaotic saddle. NHIMs control the phase space transport across an equilibrium point of saddle-centre-...-centre stability type, which is a fundamental mechanism for chemical reactions, capture and escape, scattering, and, more generally, ``transformation'' in many different areas of physics. Consequently, the presented methods and results are of broad interest. The procedure is illustrated for the spatial Hill's problem which is a well known model in celestial mechanics and which gained much interest e.g. in the study of the formation of binaries in the Kuiper belt.Comment: 12 pages, 6 figures, pdflatex, submitted to JPhys

Chemochromic Hydrogen Sensors

As fossil fuel supplies decline, hydrogen is quickly becoming an increasingly important fuel source. Currently hydrogen is the prime fuel of today's space vehicles (e.g., Space Shuttle) and featured as a fuel for some prototype vehicles such as the BMW seven series model. Hydrogen is a colorless, odorless gas with a 4% lower explosive limit which makes leak detection a priority. In an effort to support the use of hydrogen, a chemochromic (color changing) sensor was developed that is robust, simple to use, and does not require active operation. It can be made into a thin tape which can be conveniently used for leak detection at flanges, valves, or outlets. Chemochromic sensors can be either reversible or irreversible; however, irreversible chemochromic sensors will be analyzed in this report. The irreversible sensor is useful during hazardous operations when personnel cannot be present. To actively monitor leaks, testing of the irreversible sensor against environmental effects was completed and results indicated this material is suitable for outdoor use in the harsh beachside environment of Kennedy Space Center. The experiments in this report will give additional results to the environmental testing by adding solid rocket booster residue as a variable. The primary motivation for these experiments is to prepare the sensors for the launch pad environment at the Kennedy Space Center. In an effort to simulate the atmosphere at the pads before and after launch, the chemochromic sensors are exposed to solid rocket residue under various conditions

The spectrum of podocytopathies: A unifying view of glomerular diseases

Glomerular diseases encompass a broad array of clinicopathologically defined syndromes which together account for 90% of end-stage kidney disease costing $20 billion per annum to treat in the United States alone. Recent insights have defined the central role of the podocyte as both the regulator of glomerular development as well as the determinant of progression to glomerulosclerosis. We can now place all glomerular diseases within this spectrum of podocytopathies with predictable outcomes based on podocyte biology impacted by temporal, genetic, and environmental cues. This simplified construct is particularly useful to rationalize clinical effort toward podocyte preservation and prevention of progression as well as to focus basic research effort on understanding podocyte biology and for clinical research toward development of practical monitoring strategies for podocyte injury, dysfunction, and loss

The Making of a Movement: The Archival Reconstruction of Chicanismo in Northern New Mexico

The recovery of a movement is explored in this project inspired by the New Mexico Highlands University (HU) Archives and Special Collections. Known for its liberal student body in the 1960s and 1970s, I argue that HU was a catalyst for the Chicano Movement in northern New Mexico. The movement was punctuated by an influx of visitations by prominent activists such as Reies Lopez Tijerina and Rudolfo “Corky” Gonzales. Campus life at HU shifted from an Anglo-centric atmosphere to fostering a cultural space fueled by the Spanish language and the overt accusations of racism against minority students. Through my work, I show how Anglo and Chicano students confided in their school newspaper to express personal opinions and engage in racially charged correspondences across both groups. These conversations ignited a Chicano-student-based effort to elect the first Nuevomexicano and Chicano president of HU. These protests necessitated the involvement of the HU Board of Regents, whose readiness to elect a university president under such stipulations oscillated over the course of a year. Their responses to Chicano students are recorded in the HU Archives. I assert that the contrast of dialogues produced from the administrative entity and Chicano students reveals the latent racial tensions present on the HU campus. Finally, I demonstrate the manifestation of Mexican-American identity by investigating its historical contexts in New Mexico and its implications through a national lens. Post-Vietnam War sentiments speckle the racial commentary of students’ published works through art, poetry, and articles published in Spanish. By investigating primary, non-fictional sources, I work to reconstruct an historical movement and weave social commentary within a politically infused undertaking of exploring identity