As one of the key components in wavelength-division multiplexing (WDM) circuits, integrated WDM filters that are implemented on the silicon-on-insulator (SOI) platform provide a low-cost and compact solution for combining and separating multiple optical carrier signals. WDM filters are usually represented by their transmission characteristics in the frequency domain whereas their time-domain evaluation is of paramount importance for co-designing and co-optimizing with other electronic and photonic devices for achieving high-speed and high-capacity WDM circuits. This paper proposes an accurate and efficient time-domain modeling and simulation approach for WDM filters. The method starts with transmission parameters and allows for the comprehensive representation of all time-domain transmission and crosstalk characteristics within a single unified model. Notably, the built model could take into account dispersion and wavelength-dependent effects, which are often overlooked by some other modeling techniques. Through a single simulation of such model, transmission and crosstalk signals at all channels can be obtained simultaneously. To illustrate the advantages of our proposed approach, we have conducted a study involving three different types of WDM filters.

Background Human species and guinea pigs have to obtain vitamin C (VC) from food because they are unable to synthesize ascorbic acid due to the absence of the gene that encodes L-gulonolactone oxidase (Gulo). The spontaneous bone fracture (sfx) mouse is a mouse model which is deficient in the synthesis of VC because of the deletion in Gulo gene. Because muscle forces are a strong determinant of bone structure, particularly during the process of growth and development, we examined the gene expression of muscle in sfx mice.

Previously, a quantitative trait loci (QTL) for hearing loss on chromosome 16 in a 118 TNE and CAST background has been identified. The overlap of two of interval specific congenic recombinant strains (ISCRS) strains reduced the QTL interval into a 5,378,407 bps genome region. By examining the genomic information of the QTL on chromosome 16, between the two flanking markers, D16mit191 and D16mit86, we identified a total of 84 genetic elements in the 5,378,407 bps genome region. Among these genetic elements, we found seven with potential function in hearing loss preference (Table 1 ). We then examined the SNPs, insertions and deletions, and gene expression levels of those seven genes. Our current data suggest that the Kcne1 and Sod1 genes are potentially the most hearing loss relevant genes. However, further experiments and examination are still needed to confirm their candidacy. Several other candidate genes are also in the process of being identified.