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Dedicated lactation rooms are a modern development as mothers return to work while still providing breastmilk to their absent infants. This study describes the built environment microbiome of lactation rooms and daycares, and explores the influence of temperature and humidity on the microbiome of lactation rooms. Sterile swabs were used to collect samples from five different sites in lactation rooms at University of California, Davis and from five different sites in daycares located in Davis, California. DNA from the swabs was extracted and the V4 region of the 16S rRNA gene was sequenced using Illumina MiSeq. Temperature and relative humidity data were collected on a subset of the lactation rooms. Sampled lactation rooms could be either dedicated lactation rooms or could also serve other functions (e.g., combined lactation room and restroom lounge). The majority of sequence reads were identified as belonging to family Moraxellaceae, with 73% of all reads included in analysis identified as an unknown species of Acinetobacter. Alpha diversity was analyzed using the Shannon index, while beta diversity was analyzed using unweighted and weighted UniFrac distance. The Jaccard distance was used to measure amount of change at sampling locations between time points for analysis of the impact of temperature and humidity on the microbiome. There were significant differences in the beta diversity of the microbiome of lactation rooms by room type. There were also significant differences in the beta diversity of the microbiome by sample collection location. There were no significant differences in either alpha or beta diversity associated with room temperature or humidity. Additional studies are needed to understand if the differences in lactation room type may result in differences in the breastmilk microbiome of milk collected in those rooms, and to what extent any such differences may influence the infant microbiome. [ABSTRACT FROM AUTHOR]

The supramolecular organization of the two major plant polysaccharides, glucose and starch, remains poorly understood, despite decades of investigation. Almost all recent advances in the field have relied on methods requiring crystalline samples: as a consequence, relatively little is known about the so-called amorphous regions of either cellulose or starch, or the relationship between crystalline and noncrystalline regions. Parametric nonlinear optical properties such as second harmonic generation, sum frequency generation vibrational spectroscopy, and third harmonic generation are ideally suited for studying both crystalline and amorphous regions in intact samples. In this paper we review the nonlinear optical properties of cellulose and starch in the context of their molecular and supramolecular structure. We speculate on specific questions that could be addressed with this approach, and how they might contribute to a better understanding of common structural themes in biological macromolecules. [ABSTRACT FROM AUTHOR]

The molecular origins of second order nonlinear optical properties in proteins structures identified by sum-frequency vibrational spectroscopy are discussed. Noncentrosymmetry, existing at a molecular level, is translated to a macroscopic scale through non-covalent intermolecular interactions. In an alpha-helix hydrogen bonds align C=O and N--H groups parallel to a main axis. In contrast, in a collagen triple helix hydrogen bonds align C=O and N--H groups almost perpendicular to a main axis. The hydrogen bonds create a helical ladder. The effect of these unipolar and helical alignments on the second order nonlinearity is to produce achiral and chiral contributions, respectively. In the collagen triple helix, there is also an achiral contribution caused by methylene molecular groups. [ABSTRACT FROM AUTHOR]

One of the most -widely utilized absorbing boundaries for the finite difference frequency domain (FDFD) method is the perfectly matched layer (PML); however, this boundary is not ideal, as it significantly increases the computational complexity of a simulation. We compare three alternatives to the PML for modal solution using the FDFD method: the Higdon absorbing boundary condition, the complementary operators method, and the transparent absorbing boundary. These methods are integrated into an FDFD algorithm and applied to a well-known ridge waveguide test structure. The errors introduced by the absorbing boundaries are quantified in terms of propagation constant error and modal distortion, and compared to reported results using the PML. [ABSTRACT FROM AUTHOR]

Real-time process metrics are standard for the majority of fermentation-based industries but have not been widely adopted by the wine industry. In this study, replicate fermentations were conducted with temperature as the main process parameter and assessed via in-line Oxidation Reduction Potential (ORP) probes and at-line profiling of phenolics compounds by UV-Vis spectroscopy. The California and Oregon vineyards used in this study displayed consistent vinification outcomes over five vintages and are representative of sites producing faster- and slower-fermenting musts. The selected sites have been previously characterized by fermentation kinetics, elemental profile, phenolics, and sensory analysis. ORP probes were integrated into individual fermentors to record how ORP changed throughout the fermentation process. The ORP profiles generally followed expected trends with deviations revealing previously undetectable process differences between sites and replicates. Site-specific differences were also observed in phenolic and anthocyanin extraction. Elemental composition was also analyzed for each vineyard, revealing distinctive profiles that correlated with the fermentation kinetics and may influence the redox status of these wines. The rapid ORP responses observed related to winemaking decisions and yeast activity suggest ORP is a useful process parameter that should be tracked in addition to Brix, temperature, and phenolics extraction for monitoring fermentations. [ABSTRACT FROM AUTHOR]

Describes the implementation of the compound semiconductor device gallium-arsenide/aluminum-gallium-arsenide in-line fiber intensity modulator. Schematic diagram of the device structure; Phase matching of the two waveguides at specific wavelengths using distributed Bragg mirrors; Technique to modulate light intensity transmission.