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reveal that the prevalence of severe and moderate wasting were more common among children, and the overall prevalence of acute malnutrition was about 10%, indicating that it is one of the major public health problems in the country. Multivariate analysis showed that mother's BMI and media exposure, child's age and birth size, and respiratory sickness in childhood were significantly associated with both severe and moderate wasting.

We report a study on the cavity ringdown spectroscopy of acetone in both the ultraviolet (UV) and the near-infrared (NIR) spectral regions to explore the potential for development of a breath analyzer for disease diagnostics. The ringdown spectrum of acetone in the UV (282.4-285.0 nm) region is recorded and the spectrum is in good agreement with those obtained by other spectral techniques reported in the literature. The absorption cross-section of the C-H stretching overtone of acetone in the NIR (1632.7-1672.2 nm) is reported for the first time and the maximum absorption cross-section located at 1666.7 nm is 1.2 x 10(-21) cm(2). A novel, compact, atmospheric cavity with a cavity length of 10 cm has been constructed and implemented to investigate the technical feasibility of the potential instrument size, optical configuration, and detection sensitivity. The detection limit of such a mini cavity employing ringdown mirrors of reflectivity of 99.85% at 266 nm, where acetone has the strongest absorption, is approximately 1.5 ppmv based on the standard 3 criteria. No real breath gas samples are used in the present study. Discussions on the detection sensitivity and background spectral interferences for the instrument development are presented. This study demonstrates the potential of developing a portable, sensitive breath analyzer for medical applications using the cavity ringdown spectral technique.

Endohedral and exohedral polyhedral cage molecules of the form (HAO3/2)8 (A = C, Si, Ge) with double four-membered ring D4R units complexed with the atomic or ionic species (Li+, Na+, K+, F-, Cl-, Br-, He, Ne, Ar) have been investigated at the B3LYP/6-31G(d) and B3LYP/6-311++G(d,p) levels. Geometric, electronic, and energetic properties were obtained. For the endohedral complexes the noble gas atoms (X = He, Ne, and Ar) inside the cage cause the cages to expand, and the extent of the expansion depends on the size of the included atom. Endohedral alkali ions, in contrast, exhibit both attractive and repulsive interactions with the cage atoms. The cage expands when X = K+ and contracts when X = Li+ or Na+ for A = Si, Ge, and for A = C, the cage expands for all three ions. Encapsulation of the halide ions results in cage expansion throughout. Furthermore, the symmetry of the endohedral complexes when X is a cation depends critically on the relative cation and cage sizes. The binding energies of the endohedral and exohedral complexes document a clear preference for the latter, except for halides, where the endohedral complexes are more stable. The stability of endohedral complexes containing the isoelectronic species X = Na+, Ne, F- is determined by the charge transfer to the A−O cage bonding sites. The formation of the endohedral complexes is discussed in terms of transition states that connect the exohedral and endohedral minima as well as the activation barriers for insertion of the guest into the cage. Our studies predict that a fluoride anion can penetrate into the (HAO3/2)8 cage without destroying it. For X = Cl-, in contrast, the cage ruptures upon insertion of the impurity.

Modern computational methods have proved invaluable for the design and analysis of structural components using lightweight materials. The challenge of optimizing lightweight materials in the design of industrial components relates to incorporating structure-property relationships within the computational strategy to incur robust designs. One effective methodology of incorporating structure-property relationships within a simulation-based design framework is to employ a hierarchical multiscale modeling strategy. This paper reviews techniques of multiscale modeling to predict the mechanical behavior of amorphous polymers. Hierarchical multiscale methods bridge nanoscale mechanisms to the macroscale/continuum by introducing a set of structure-property relationships. This review discusses the current state of the art and challenges for three distinct scales: quantum, atomistic/coarse graining, and continuum mechanics. For each scale, we review the modeling techniques and tools, as well as discuss important recent contributions. To help focus the review, we have mainly considered research devoted to amorphous polymers.

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