Poverty has been shown to negatively influence child health and development along a number of dimensions. For example, poverty-net of a variety of potentially confounding factors-is associated with increased neonatal and postneonatal mortality rates, greater risk of injuries resulting from accidents or physical abuse/neglect, higher risk for asthma, and lower developmental scores in a range of tests at multiple ages.Despite the extensive literature available that addresses the relationship between poverty and child health and development, as yet there is no consensus on how poverty should be operationalized to reflect its dynamic nature. Perhaps more important is the lack of agreement on the set of controls that should be included in the modeling of this relationship in order to determine the "true" or net effect of poverty, independent of its cofactors. In this paper, we suggest a general model that should be adhered to when investigating the effects of poverty on children. We propose a standard set of controls and various measures of poverty that should be incorporated in any study, when possible. 463

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This study describes a green method for preparing all-cellulose nanocomposites through a dissolution and regeneration process. Cotton linter pulp was dissolved in 7 wt % NaOH/12 wt % urea aqueous solution precooled to −12 C. Self-assembly of cellulose molecules into nanostructured cellulose fiber is achieved by using water addition and controlling the temperature to regenerate cellulose. By changing the microenvironment of the cellulose solution, the morphology of the nanostructured cellulose fibers and the mechanical properties of the regenerated cellulose films can be tuned. Then, a series of regenerated cellulose films have been prepared and characterized from various aspects. Compared with other all-cellulose films in the literature, the regenerated all-cellulose nanocomposite films prepared in this work exhibited good optical transparency, thermal stability, and excellent tensile strength (up to 135 MPa) when the regeneration temperature was adjusted to 50 C. This work provided a green and promising approach to prepare high-performance and environmentally friendly all-cellulose nanocomposites.These two authors contributed equally to this work.

To improve the epitaxial crystallization ability of poly(3-hexylthiophene) (P3HT) on a highly oriented polyethylene (PE) substrate, controlled solvent vapor treatment (CSVT) is employed. The anisotropic structures and related optical properties depend not only on the solvent used to prepare the film but also on the subsequent solvent vapor treatment pressure and time. A highly oriented PE film facilitates the "side-on" chain orientation of P3HT with its c axis parallel to the drawing direction of the PE film. The dichroic ratio (DR) of the P3HT film reflected by UV−vis spectra can reach as high as 7.1, which is much larger than the value treated by thermal annealing. Moreover, the excitation bandwidth W, indicating the effective conjugation length and molecular order, shows significant anisotropic features. Solvent used for solution processing with a high boiling point is more favorable for inducing anisotropic multiscale structures. In particular, the oriented structures lead to obvious anisotropic carrier mobility. The carrier mobility of P3HT after CSVT along the PE molecular chain direction is 7.5 times higher than that measured perpendicular to the PE chain direction. This is of great importance in fabricating anisotropic thin films of conjugated polymeric semiconductors with enhanced performance.

In this paper, a kind of novel filaments/short fibers composite yarns containing stainless steel (SS) were produced by an innovative ring-spinning method. On the basis of the shielding mechanism of the electromagnetic (EM) shielding material, a method for fabricating a multifunctional SS composite fabric with EM shielding characteristics was successfully developed. Coaxial transmission line method was used to investigate the influences of different factors, such as radiant frequency, metal content, metal mesh size, and geometry, on electromagnetic shielding effectiveness (EMSE) of the composite fabrics in the frequency range of 15-3000 MHz. The notabilities of these factors were examined using analysis of variance (ANOVA). A regression model equation was setup using the above factors as variables, and verification of accuracy and practicability to this model was also carried out. The experimental results indicate that average EMSE of composite fabrics is 20.76-51.92 dB in the frequency of 15-3000 MHz, which indicates that the influence of the studied factors was considerable.

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