Study of rock experiments to measure interplanetary energetic hydrogen fluxes and hydrogen fluxes during an auroral breakup

Flux, energy spectra, and pitch angle distributions of precipitated low energy hydrogen and electrons from Nike-Tomahawk auroral hydrogen experimen

Auroral rocket experiment 2 Final report

Detecting fluxes of energetic neutral hydrogen atoms in interplanetary medium by auroral rocket flight

Measurement of angular distributions by use of low-coherence interferometry for light-scattering spectroscopy

We present a novel interferometer for measuring angular distributions of backscattered light. The new system exploits a low-coherence source in a modified Michelson interferometer to provide depth resolution, as in optical coherence tomography, but includes an imaging system that permits the angle of the reference field to be varied in the detector plane by simple translation of an optical element. We employ this system to examine the angular distribution of light scattered by polystyrene microspheres. The measured data indicate that size information can be recovered from angular-scattering distributions and that the coherence length of the source influences the applicability of Mie theory

Phase-dispersion optical tomography

We report on phase-dispersion optical tomography, a new imaging technique based on phase measurements using low-coherence interferometry. The technique simultaneously probes the target with fundamental and second-harmonic light and interferometrically measures the relative phase shift of the backscattered light fields. This phase change can arise either from reflection at an interface within a sample or from bulk refraction. We show that this highly sensitive 5 phase technique can complement optical coherence tomography, which measures electric field amplitude, by revealing otherwise undetectable dispersive variations in the sample

Study of an auroral zone rocket experiment Final report

Measurement of flux and energy spectra of protons, energetic particles, hydrogen atoms, and electrons in auroral zone by Nike-Tomahawk sounding rocke

Determination of particle size by using the angular distribution of backscattered light as measured with low-coherence interferometry

We employ a novel interferometer to measure the angular distribution of light backscattered by a turbid medium. Through comparison of the measured data with the predictions of Mie theory, we are able to determine the size of the scatterers comprising the medium with subwavelength precision. As the technique is based on low-coherence interferometry, we are able to examine the evolution of the angular distribution of scattered light as it propagates into the medium. The effects of multiple scattering as a function of penetration depth in the medium are analyzed. We also present various considerations for extending this technique to determining structural information in biological tissues, such as the effects of a distribution of particle sizes and the need to average out speckle contributions

Phase-referenced interferometer with subwavelength and subhertz sensitivity applied to the study of cell membrane dynamics

We report a highly sensitive means of measuring cellular dynamics with a novel interferometer that can measure motional phase changes. The system is based on a modified Michelson interferometer with a composite laser beam of 1550-nm low-coherence light and 775-nm CW light. The sample is prepared on a coverslip that is highly reflective at 775nm. By referencing the heterodyne phase of the 1550-nm light reflected from the sample to that of the 775-nm light reflected from the coverslip, small motions in the sample are detected, and motional artifacts from vibrations in the interferometer are completely eliminated. We demonstrate that the system is sensitive to motions as small as 3.6nm and velocities as small as 1nm/s. Using the instrument, we study transient volume changes of a few (approximately three) cells in a monolayer immersed in weakly hypotonic and hypertonic solutions

Interferometric phase-dispersion microscopy

We describe a new scanning microscopy technique, phase-dispersion microscopy (PDM). The technique is based on measuring the phase difference between the fundamental and the second-harmonic light in a novel interferometer. PDM is highly sensitive to subtle refractive-index differences that are due to dispersion (differential optical path sensitivity, 5 nm). We apply PDM to measure minute amounts of DNA in solution and to study biological tissue sections. We demonstrate that PDM performs better than conventional phase-contrast microscopy in imaging dispersive and weakly scattering samples

Harmonic phase-dispersion microscope with a Mach-Zehnder interferometer

Harmonic phase-dispersion microscopy (PDM) is a new imaging technique in which contrast is provided by differences in refractive index at two harmonically related wavelengths. We report a new configuration of the harmonic phase-dispersion microscope in a Mach-Zehnder geometry as an instrument for imaging biological samples. Several improvements on the earlier design are demonstrated, including a single-pass configuration and acousto-optic modulators for generating the heterodyne signals without mechanical arm scanning. We demonstrate quantitative phase-dispersion images of test structures and biological samples

Collaborating with Families: Supporting and Including Caregivers in Early Intervention

An essential element of early intervention services is the inclusion of families throughout the intervention process. Caregiver-mediated intervention consists of caregiver coaching and collaboration, supporting interactions between the caregiver and child, as well as supporting caregiver learning and competence (Friedman & Woods, 2012). In order to implement caregiver-mediated intervention, early intervention providers must hone their abilities to collaborate with and support caregivers to deliver high-quality services, empower caregivers, and build competence (Friedman & Woods, 2012). It is important for interventionists to build consensus with caregivers on the child’s short term and long term goals, as well as opportunities for learning within the family’s everyday activities. During the initial stages of intervention, it is critical for interventionists to gain information from families, as well as share information related to child development and the child’s needs. It is important that early intervention providers have coaching strategies and conversational strategies to ensure their conversations are clear, supportive, collaborative, and educational in order for caregivers to best implement strategies for their children. Interventionists should use coaching strategies to match caregivers where they are, from the initial stages of intervention to caregiver independence, ultimately building caregiver capacity. An interventionist’s ability to recognize family strengths and stressors while coaching caregivers is essential to successful early intervention, and can naturally lead to opportunities for crucial conversations surrounding the child’s development, the family system, and family stressors and supports. These conversations are built on a foundation of sharing and gaining sensitive information with a caregiver about the family as a whole and the child’s particular needs. Collaboration with families and building capacity in caregivers are ongoing processes throughout the course of early intervention, allowing caregivers to be well-equipped to utilize skills in everyday life as children continue to grow and develop