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The height-height correlation function for a fluctuating interface between two coexisting bulk phases is derived by means of general equilibrium properties of the corresponding density-density correlation function. A wavelength-dependent surface tension $\gamma(\mathbf{q})$ can be defined and expressed in terms of the direct correlation function $c(\mathbf{r},\mathbf{r}')$, the equilibrium density profile $\rho_{\circ}(\mathbf{r})$ and an operator which relates density to surface configurations. Neither the concept of an effective interface Hamiltonian nor the difference in pressure is needed to determine the general structure of the height-height correlations or $\gamma(\mathbf{q})$, respectively. This result generalizes the Mecke/Dietrich surface tension $\gmd$ (Phys. Rev. E {\bf 59}, p. 6766 (1999)) and modifies recently published criticism concerning $\gmd$ (P. Tarazona, R. Checa and, E.Chac\'{o}n: Phys. Rev. Lett. {\bf 99}, p. 196101 (2007))., Comment: 8 pages, 1 figure

Thermally excited capillary waves at fluid interfaces in binary liquid mixtures exhibit simultaneously both density and composition fluctuations. Based on a density functional theory for inhomogeneous binary liquid mixtures we derive an effective wavelength dependent Hamiltonian for fluid interfaces in these systems beyond the standard capillary-wave model. Explicit expressions are obtained for the surface tension, the bending rigidities, and the coupling constants of compositional capillary waves in terms of the profiles of the two number densities characterizing the mixture. These results lead to predictions for grazing-incidence x-ray scattering experiments at such interfaces., Comment: 23 pages, 11 figures

This study examined the relationship between maternal stress, changes in stress, specific stressors, and social support and quality of mother-infant attachment. Life stress of 132 mothers was assessed prenatally and when the child was 13 months old. The mothers' social support and the quality of infant-mother attachment were also measured at the child's 13th month, the latter by means of the Ainsworth Strange Situation procedure. Results indicated that high stress at 13 months, and an increase in stress from the prenatal period to 13 months, were associated with infants' anxious-resistant attachment in the strange situation. Partner stress, and stress related to changes in family relationships, differed significantly depending on attachment classification in the strange situation. Among mothers who reported low social support, there were no significant differences between the level of stress of mothers whose infants exhibited anxious-resistant attachment in the strange situation, and the stress of mothers whose infants exhibited anxious-avoidant or secure attachment. Eight references are cited. (BC)

Explored within-group effects of mother-infant attachment and day care on children's social and emotional development in a high-risk, low income sample of mothers and infants who entered day care early, and a home-reared, middle-class sample of infants and their mothers. Found that the effects of early day care are influenced by security of attachment. (DR)

A child abuse assessment center was created in Dade County, Florida, and was funded by state and local government sources. Staff includes a project director, two clinical social workers, a follow-up case monitor, clerical support, and a psychologist. The center attempts to minimize trauma to the child victim of sexual and physical abuse by a reduction in the number of interviews the child will experience. This is accomplished by center staff interviewing the child in a sensitive environment, videotaping the interview, and by inter-agency coordination. The center assists in developing a sufficient legal case (if appropriate) for prosecutorial purposes by blending investigatory and clinical dimensions in interviewing. The center develops a plan for treatment and follow-up for the child and family as a result of a comprehensive assessment. Useful practices and procedures were found to include the following: (1) despite community support for such a program, the program needs to be carefully planned; (2) before services are provided, agencies should sign co-agreements describing division of responsibilities; (3) in developing protocols, line level input as well as administrative input is necessary for implementation; (4) an advisory board with representatives from the agencies, community, and state is needed; (5) multiple funding sources necessitate clear intent and clearly stated restrictions on the funds; and (6) intra-familial as well as extra-familial abuse should be given balanced consideration. (ABL)

The process of siting large wind turbines may be divided into two broad steps: site selection, and site evaluation. Site selection is the process of locating windy sites where wind energy development shows promise of economic viability. Site evaluation is the process of determining in detail for a given site the economic potential of the site. The state of the art in the first aspect of siting, site selection is emphasized. Several techniques for assessing the wind resource were explored or developed in the Federal Wind Energy Program. Local topography and meteorology will determine which of the techniques should be used in locating potential sites. None of the techniques can do the job alone, none are foolproof, and all require considerable knowledge and experience to apply correctly. Therefore, efficient siting requires a strategy which is founded on broad based application of several techniques without relying solely on one narrow field of expertise.

A time domain reflectometer is considered as a closed loop, one-dimensional radar system. Applying the principle of time domain reflectometry to the detection of cryogenic liquid levels, measurements on the order of + or - 0. 3% of total liquid level probe length are possible. The time domain reflectometer liquid level measurement is independent of liquid density variations and is simple to calibrate and operate. Construction of the liquid level sensing probe is described.

NASA-SRI Round Robin Ablation Program summary, discussing dimensional analysis, Teflon, nylon and surface temperature

Ablation characteristics of heat shield materials measured in arc heated wind tunnels, considering influence of model scale, heating rate and pressure level

Comparative evaluation of ablative materials in arc plasma jets

Comparative evaluation of ablative materials in arc jet plasmas

Teflon and high density phenolic-nylon models evaluated at various enthalpies and heating rates under supersonic conditions

Work done to date is reported concerning Radio Frequency Mass Quantity Gauging. Experimental apparatus has been designed and tested which measures the resonant frequencies of a tank in the time domain. These frequencies correspond to the total mass of fluid within the tank. Experimental results are discussed for nitrogen and hydrogen in normal gravity both in the supercritical state and also in the two phase (liquid-gas) region. Theoretical discussions for more general cases are given.