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Clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas) systems are prokaryotic adaptive immune systems against invading nucleic acids. CRISPR locus variability has been exploited in evolutionary and epidemiological studies of Mycobacterium tuberculosis, the causative agent of tuberculosis, for over 20 yr, yet the biological function of this type III-A system is largely unexplored. Here, using cell biology and biochemical, mutagenic, and RNA-seq approaches, we show it is active in invader defense and has features atypical of type III-A systems: mature CRISPR RNA (crRNA) in its crRNA-CRISPR/Cas protein complex are of uniform length (∼71 nt) and appear not to be subject to 3'-end processing after Cas6 cleavage of repeat RNA 8 nt from its 3' end. crRNAs generated resemble mature crRNA in type I systems, having both 5' (8 nt) and 3' (28 nt) repeat tags. Cas6 cleavage of repeat RNA is ion dependent, and accurate cleavage depends on the presence of a 3' hairpin in the repeat RNA and the sequence of its stem base nucleotides. This study unveils further diversity among CRISPR/Cas systems and provides insight into the crRNA recognition mechanism in M. tuberculosis, providing a foundation for investigating the potential of a type III-A-based genome editing system.-Wei, W., Zhang, S., Fleming, J., Chen, Y., Li, Z., Fan, S., Liu, Y., Wang, W., Wang, T., Liu, Y., Ren, B., Wang, M., Jiao, J., Chen, Y., Zhou, Y., Zhou, Y., Gu, S., Zhang, X., Wan, L., Chen, T., Zhou, L., Chen, Y., Zhang, X.-E., Li, C., Zhang, H., Bi, L. Mycobacterium tuberculosis type III-A CRISPR/Cas system crRNA and its maturation have atypical features.

A new type of all fiber inline Mach-Zehnder interferometer (MZI) based on single mode-multimode-thin core-multimode optical fiber and cascaded with a fiber Bragg grating (FBG) structure is proposed. Its temperature performance is experimental studied. In our experiments, the sensitivity of this MZI is about 157pm/℃ from 17 to 95°C. When FBG is heated only, the temperature sensitivity of FBG cascaded MZI is 9.83pm/℃. It can be found that the reference spectrum dip wavelength of MIZ can be modulated by cascaded FBG.

The defects detection based on algorithms of discrete wavelet packet transform and back propagation artificial neural network is described firstly. Then the reconfigurable architecture of the defects detection in embedded reconfigurable system is discussed. Upon the reconfigurable architecture, the algorithms of discrete wavelet packet transform and back propagation neural net work are rearranged. The reconfigurable architectures of both algorithms are carried out eventually. According to the experiments of ultrasonic signal processing, the reconfigurable architecture of the defect detection can provides a flexible and efficient solution to embedded reconfigurable signal processing system.