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Objectives The present study sought to examine the association between maternal depressive symptoms and characteristics of offspring physical health, including health status, health behaviors, and healthcare utilization, among low-income families. Maternal engagement was explored as a mediator of observed effects. Methods Cross-sectional survey data from a community sample of 4589 low-income women and their preschool-age children participating in the WIC program in Los Angeles County were analyzed using logistic, Poisson, and zero-inflated negative binomial regression. Mediation was tested via conditional process analyses. Results After controlling for the effects of demographic characteristics including maternal health insurance coverage, employment status, education, and preferred language, children of depressed women (N = 1025) were significantly more likely than children of non-depressed women (N = 3564) to receive a "poor" or "fair" maternal rating of general health (OR 2.34), eat fewer vegetables (IRR: 0.94) more sweets (IRR: 1.20) and sugary drinks daily (IRR: 1.32), and consume fast food more often (OR 1.21). These children were also less likely to have health insurance (OR 1.59) and more likely to receive medical care from a public medical clinic or hospital emergency room (OR 1.30). Reduced maternal engagement partially mediated associations between maternal depressive symptoms and several child health outcomes including poor diet, health insurance coverage, and use of public medical services. Conclusions for Practice Maternal depressive symptoms are associated with poor health among preschool-age children in low-income families. Prevention, screening, and treatment efforts aimed at reducing the prevalence of maternal depression may positively affect young children's health.

Studies of electrosensory systems have led to insights into a number of general issues in biology. However, investigations of these systems have been limited by the inability to precisely control spatial patterns of electrosensory input. In this paper, an electrode array and a system to selectively stimulate spatially restricted regions of an electroreceptor array are presented. The array has 96 channels consisting of chrome/gold electrodes patterned on a flexible parylene‐C substrate and encapsulated with another parylene‐C layer. The conformability of the electrode array allows for optimal current driving and surface interface conditions. Recordings of neural activity at the first central processing stage in weakly electric mormyrid fish support the potential of this system for high spatial resolution stimulation and mapping of electrosensory systems. [ABSTRACT FROM AUTHOR]

Presents a case study of a middle school with discipline problems leading to high suspension rates. The school implemented a voluntary peer mediation program as part of a comprehensive conflict resolution program. Discusses the program's objectives, selection and training of students, implementation, supervision of mediators, and program evaluation. (KW)

In this paper, the authors report on the investigation on the effect of inserting an epitaxial MgO layer on the structural and magnetic properties of [Fe.sub.3][O.sub.4] ultrathin films grown on GaAs(100) by combined techniques of molecular beam epitaxy and postgrowth annealing in an oxygen atmosphere. The MgO films were grown with a cube-on-cube orientation to GaAs. The epitaxial [Fe.sub.3][O.sub.4] lattice cell was rotated by 45[degrees] in respect to that of MgO and GaAs due to the lattice relaxation of the magnetic layer. All samples studied exhibited strong fourfold cubic magnetic anisotropy with easy axes along the directions of GaAs. A dramatic decrease in the uniaxial anisotropy constant in the presence of the MgO barrier was observed. The existence of the uniaxial magnetic anisotropy in the [Fe.sub.3][O.sub.4]/GaAs hybrid structure has been attributed to the interfacial contact between the magnetite film and the GaAs. Index Terms--Half metal, magnetic anisotropy, magnetite, molecular beam epitaxy, spintronics.

A prototype instrument is presented which can quickly and cost-effectively make noncontact measurements of giant magnetoresistance (GMR). The instrument is based on the magnetorefractive effect (MRE) which has previously been shown to be strongly related to GMR in metallic materials. The realization of the instrument exploits mid-to-far infrared transmitting optical fibers which shield the infrared radiation from the environment and enable its efficient focussing. The instrument is tested on a GMR CoFe/Cu multilayer and its response compared to a control sample of Cr. Index Terms--Giant magnetoresistance (GMR), infrared magnetorefractive effect, magnetorefractive effect (MRE), noncontact GMR measurement.

A new method for correlating the far infrared magnetorefractive effect (MRE) and giant magnetoresistance (GMR) is tested on commercially grown CoFe/Cu multilayers. Parameters are determined to demonstrate a simple relationship between prominent features of an MRE spectrum and the size of the electrical magnetoresistance. The results encourage the use of the new approach for sensing GMR in thin films. Index Terms--Conductivity, giant magnetoresistance, infrared spectroscopy, magnetic films, magnetooptic effects.

We report the evolution of Fe oxide nanostructures on GaAs(100) upon pre- and post-growth annealing conditions. GaAs nanoscale pyramids were formed on the GaAs surface due to wet etching and thermal annealing. An 8.0-nm epitaxial Fe film was grown, oxidized, and annealed using a gradient temperature method. During the process the nanostripes were formed, and the evolution has been demonstrated using transmission and reflection high energy electron diffraction, and scanning electron microscopy. These nanostripes exhibited uniaxial magnetic anisotropy. The formation of these nanostructures is attributed to surface anisotropy, which in addition could explain the observed uniaxial magnetic anisotropy. Index Terms--Annealing, magnetic Fe oxide, magnetic uniaxial anisotropy, nanostructures.

Ultrathin Fe oxide films of various thicknesses prepared by post-growth oxidation on GaAs(100) surface have been investigated with X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), and X-ray magnetic circular dichroism (XMCD). The XPS confirms that the surfaces of the oxide are [Fe.sub.3][O.sub.4] rather than [Fe.sub.2][O.sub.3]. XAS and XMCD measurements indicate the presence of insulating Fe divalent oxide phases (FeO) beneath the surface [Fe.sub.3][O.sub.4] layer with the sample thickness above 4 nm. This FeO might act as a barrier for the spin injection into the GaAs. Index Terms--Half-metallic [Fe.sub.3][O.sub.4], post-growth oxidation, spintronics, XMCD.

Spin injection into and spin transport through silicon space layers in iron/silicon/cobalt structures are investigated. Sharp metal-semiconductor interfaces were achieved in this way, but no spin dependent transport, putting an upper limit on the spin diffusion length in device quality silicon wafers.

The effect of the micromagnetic configuration on the giant magnetoresistance of a metastable cobalt-silver thin film prepared by sputtering is investigated. The difference between the magnetoresistance immediately after cooling in zero field and after field cycling is interpreted by invoking interactions between the active magnetic regions in the sample.

The feasibility of using the magnetorefractive effect (MRE) in reflection mode for the measurement of GMR in Co(sub 30)Ag(sub 70) granular films is demonstrated. The angular dependence of the s-polarization enhancement and the region of negative MRE are not easily explained and may stem from phenomena related to macroscopic structure within the film.

The spin polarising properties of the iron oxide magnetite ( Fe 3 O 4 ) make it attractive for use in spintronic devices, but its sensitivity to compositional and structural variations make it challenging to prepare reliably. Infrared microspectroscopy and modelling are used to determine the spatial variation in the chemical composition of three thin films of iron oxide; one prepared by pulsed laser deposition (PLD), one by molecular beam epitaxy (MBE) deposition of iron whilst simultaneously flowing oxygen into the chamber and one by flowing oxygen only once deposition is complete. The technique is easily able to distinguish between films which contain metallic iron and different iron oxide phases as well as spatial variations in composition across the films. The film grown by post-oxidising iron is spatially uniform but not fully oxidised, the film grown by simultaneously oxidising iron showed spatial variation in oxide composition while the film grown by PLD was spatially uniform magnetite. [ABSTRACT FROM AUTHOR]