Experimental demonstration of a classical analog to quantum noise cancellation for use in gravitational wave detection.

We present results that are a classical analog to quantum noise cancellation. It is possible to breach the standard quantum limit in an interferometer by the use of squeezing to correlate orthogonal quadratures of quantum noise, causing their effects on the resulting sensitivity to cancel. A laser beam incident on a Fabry-Perot cavity was imprinted with classical, correlated noise in the same quadratures that cause shot noise and radiation pressure noise. Couplings between these quadratures due to a movable mirror, sensitive to radiation pressure, cause the excess classical noise to cancel. This cancellation was shown to improve the signal to noise ratio of an injected signal by approximately a factor of 10.

Lock acquisition of a gravitational-wave interferometer.

Interferometric gravitational-wave detectors, such as the Laser Interferometer Gravitational Wave Observatory (LIGO) detectors currently under construction, are based on kilometer-scale Michelson interferometers, with sensitivity that is enhanced by addition of multiple coupled optical resonators. Reducing the relative optic motions to bring the system to the resonant operating point is a significant challenge. We present a new approach to lock acquisition, used to lock a LIGO interferometer, whereby the sensor transformation matrix is dynamically calculated to sequentially bring the cavities into resonance.

Comparison of soluble and immobilized acetate for removing Pb from contaminated soil.

Five lead (Pb) contaminated soils were used in a laboratory and modeling study to examine the effects of soluble and immobilized acetate on Pb removal from a contaminated soil as a function of pH. Soluble acetate was added as sodium acetate; immobilized acetate was added in the form of a cation exchange resin. For comparative purposes, Pb adsorption with no acetate also was measured as a function of pH. A surface complexation modeling framework was used to interpret experimental data. Experimental results showed the cation exchange resin was much more effective than soluble acetate in removing Pb from soils due to a strong affinity of the resin for Pb. In addition, concentrations of soluble Pb in resin/soil slurry were very low, minimizing the pollution threat if discharged. As deduced from modeling studies, soluble acetate performed poorly compared to the resin, in part, due to adsorption of the soluble PbAc(+) complex. The effectiveness of both soluble and immobilized acetate was diminished below pH 4 as a result of competition by H(+) for acetate. Modeling results based on resin affinity for Pb compare well with experimental data for resin/soil mixtures, suggesting that Pb partitioning in resin/soil mixtures may be predicted reasonably well if soil/Pb and resin/Pb partitioning are known. Thus, the modeling approach may be used as a screening tool to determine the performance of alternative resins.

Analysis of light noise sources in a recycled Michelson interferometer with Fabry-Perot arms.

We present a method by which the effect of laser field variations on the signal output of an interferometric gravitational wave detector is rigorously determined. Using the Laser Interferometer Gravitational Wave Observatory (LIGO) optical configuration of a power recycled Michelson interferometer with Fabry-Perot arm cavities as an example, we calculate the excess noise after the input filter cavity (mode cleaner) and the dependence of the detector strain sensitivity on laser frequency and amplitude noise, radio frequency oscillator noise, and scattered-light phase noise. We find that noise on the radio frequency sidebands generally limits the detector's sensitivity.

Arm cavity resonant sideband control for laser interferometric gravitational wave detectors.

We present a new optical control scheme for a laser interferometric gravitational wave detector that has a high degree of tolerance to interferometer spatial distortions and noise on the input light. The scheme involves resonating the rf sidebands in an interferometer arm cavity.

Treatment of the refractory schizophrenic patient.

As antipsychotic treatment evolves toward a broader range of efficacy and more benign side effect profiles, our criteria for treatment-refractory schizophrenia may become more subtle. Unidimensional concepts of treatment resistance may be replaced by multiaxial descriptions of the target symptoms, side effects, and compliance issues that limit the ultimate goals of enhanced psychosocial function and quality of life. Augmentation strategies, increasing insight into dose response relationships, and atypical agents may benefit patients who failed to respond to or tolerate previous therapies. The advantages of newer agents in treatment-resistant schizophrenia may arise in part from their preferential targeting of newer agents in treatment-resistant schizophrenia may arise in part from their preferential targeting of mesolimbic compared with motor and tuberoinfundibular dopaminergic pathways.

Interleukin-1 beta and tumor necrosis factor-alpha production by human monocytes cultured with L-thyroxine and thyrocalcitonin: relation to severe root shortening.

The objectives of this study were to determine whether L-thyroxine (T4) and thyrocalcitonin (TCA) influence monocyte production of interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) and to examine IL-1 beta and TNF-alpha production in monocytes from a group of orthodontic patients with severe root shortening. Human monocytes were incubated with varying concentrations of T4 and TCA for 24 hours, and IL-1 beta and TNF-alpha levels were measured by ELISA. At a concentration of 0.1 microgram/ml, T4 and TCA induced significantly more IL-1 beta than untreated controls, and T4 induced more IL-1 beta than TCA. Neither hormone induced significant TNF-alpha release, conversely, TCA had an inhibitory effect on unstimulated monocyte release of TNF-alpha. TCA was also shown to inhibit, but not reverse, the activational effect of lipopolysaccharide on monocyte TNF-alpha release. T4 and TCA concentrations as low as 0.1 pg/ml caused monocytes to release significant amounts of IL-1 beta. The highest concentration of T4 tested (1.0 microgram/ml) induced significantly less IL-1 beta production than lower concentrations. T4- and TCA-treated monocytes bound more labeled IL-1 beta than untreated controls, which suggests that these hormones increase IL-1 receptor expression. There was a wide range of unstimulated and stimulated IL-1 beta and TNF-alpha production by root resorption subject monocytes with no significant differences between resorption and nonresorption group means. This data suggest that patient monocytes did not differ from control monocytes in regard to these cytokine parameters, and therefore in vitro IL-1 beta and TNF-alpha levels could not distinguish resorption subjects.

Demonstration of a power-recycled Michelson interferometer with Fabry-Perot arms by frontal modulation.

Large-scale gravitational-wave detectors currently under construction such as the LIGO detectors use multiplemirror resonant optical systems containing several surfaces at which the relative phase of interfering light beams must be controlled. We describe a tabletop experiment that demonstrates a scheme for extracting signals in such an interferometer corresponding to deviations from perfect interference.

Immunohistochemical mapping of epidermal growth-factor receptors in normal human oral soft tissue.

Epidermal growth-factor receptor (EGF-r) has been identified on basilar cells of stratified squamous epithelia and skin adnexa in man. Recent studies have mapped EGF-r to various oral cells in animals; however, complete mapping of EGF-r in normal human oral mucosa has not been done. Normal tissues from eight sites in human oral mucosa were examined for their expression of EGF-r using avidin-biotin peroxidase complex with mouse anti-EGF-r monoclonal antibody. Immunoreactivity was detected in palatal gingiva, buccal gingiva, soft palate, lateral tongue, dorsal tongue and floor of the mouth. The connective tissues of the periodontal ligament and dental pulp were non-reactive. EGF is known to exist in most body fluids, particularly saliva. In normal human mucosa, EGF is localized to connective tissue subjacent to epithelium. With the receptor in the overlying epithelium, a possible epithelial-mesenchymal interaction may exist between the receptor and ligand. A paracrine mode of action may be postulated, functioning to regulate the complex biological functions of the human oral tissues.

LIGO: The Laser Interferometer Gravitational-Wave Observatory.

The goal of the Laser Interferometer Gravitational-Wave Observatory (LIGO) Project is to detect and study astrophysical gravitational waves and use data from them for research in physics and astronomy. LIGO will support studies concerning the nature and nonlinear dynamics of gravity, the structures of black holes, and the equation of state of nuclear matter. It will also measure the masses, birth rates, collisions, and distributions of black holes and neutron stars in the universe and probe the cores of supernovae and the very early universe. The technology for LIGO has been developed during the past 20 years. Construction will begin in 1992, and under the present schedule, LIGO's gravitational-wave searches will begin in 1998.

Brightness Temperatures of Saturn's Disk and Rings at 400 and 700 Micrometers.

Saturn was observed in two broad submillimeter photometric bands with the rings nearly edge-on. The observed brightness temperatures fall below the predictions of atmospheric models constructed from data at shorter wavelenths, indicating the presence of an opacity source besides pressure-broadened hydrogen lines in the submillimeter region. In combination with earlier measurements at larger inclination angles, these results yield a 400-micrometer brightness temperature for the rings of approximately 75 K.

Compact infrared heat trap field optics.

A design is presented for achieving compact ir heat trap field optics by incorporation of a lens into the light collector.