CAZymes-associated method to explore glycans that mitigate DSS-induced colitis via targeting Bacteroides cellulosilyticus.

Improving Bacteroides cellulosilyticus abundance is a feasible approach to treating inflammatory bowel disease (IBD). Although B. cellulosilyticus is responsive to dietary components, untargeted manipulation cannot focus on target microbe and lead to an increase in harmful bacteria in the microbiota. Breakthroughs in methods for regulating specific microbes, but the protocols are expensive, time-consuming, and difficult to follow. Glycans based on microbial-carbohydrate-active enzymes (CAZymes) would provide a potential solution. We propose a method based on CAZymes to explore polysaccharides that target specific gut microbes and alleviate diseases. The designed polysaccharides (Arabinogalactan, AG) enrich the abundance of B. cellulosilyticus in single-strain co-cultures, fermentation in vitro, and mouse models in vivo. Supplementation with AG relieved mice from colitis and clinical symptoms. We reveal that AG directly alters B. cellulosilyticus level and cooperative microbes, resulting in remission of colitis. Our glycan design pipeline is a promising way to improve disease through the targeted enhancement of specific microbes.

Polarization independent 4-stage OTDM multiplexer using plated GRIN lens.

In this paper, a 4-stage optical time domain multiplexing (OTDM) multiplexer based on plated graded index (GRIN) lens is proposed and experimentally demonstrated. A 10Gbit/s return-to-zero (RZ) signal is upgraded to 160Gbit/s. The time-domain accuracy of the multiplexer is evaluated by analyzing the multiplexed 160Gbit/s signal. Experimental results validate the stability of the optical multiplexing behavior and the polarization insensitivity of the proposed multiplexer. The results also show the advantages of our OTDM multiplexer such as the flexible output signal speeds at the output of different stages, the low insertion loss and the temperature and wavelength stability.

Tunable PMD compensator based on highbirefringence.

The simple structure of a tunable polarization mode dispersion (PMD) compensator based on a cantilever beam and a high-birefringence linearly chirped fiber Bragg grating is proposed. A cantilever structure is used to introduce a linear strain gradient on the grating, and we can tune the compensated differential group delay (DGD) at a fixed signal wavelength just by changing the displacement at the free end of the beam. Based on numerical simulations, the performance of the cantilever structure as a PMD compensator is assessed for 10-Gbits/s nonreturn-to-zero transmission systems with a large DGD. With this compensator, a significant improvement of system performance can be achieved in the eye pattern of a received signal.

Analytical theory for polarization mode dispersion of spun and twisted fiber.

We derive an analytical expression for differential group delay of spun and twisted fibers, which should provide valuable guidance for optimization of such parameters to produce low polarization mode dispersion fiber.