The hypermethylation in the promoter region of the SEPT9 gene is associated with the development of colorectal cancer (CRC). Although its clinical significance for early diagnosis and screening of CRC has been demonstrated, the tedious operations in the conventional DNA methylation (DNAm) detection hinder its wide application. Herein, an electronic method for determining SEPT9 methylation in CRC patients is proposed by using the carbon dot-modified liquid exfoliated graphene field effect transistor (CDs-LEG-FET) as the DNAm sensor, the specifically designed probes to capture the SEPT9 gene and the immunologic recognition to recognize 5-methylcytosine (5mC) positions on the anchored sequences. The identification and nanomorphology of the as-prepared materials and devices are executed first by the characterizations of UV−vis, Raman, atomic force microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and electronic measurements. Then, the role of CDs in enhancing DNAm sensitivity of CD-LEG-FET is manifested by comparing it with that of CD-free LEG-FET. Third, the captured SEPT9 genes on CD-LEG-FETs by different probes are evaluated, and the optimized temperature for hybridizing the target ssDNA sequences is determined to be 48 °C. Furthermore, the detection sensitivity for the low-quantity of DNA samples is demonstrated to be as low as 2 ng. Finally, the methylation degree of the tumor and corresponding noncancerous tissue DNA samples were examined by the proposed electric method and methylight assay in parallel. The diagnostic value of the electrical assay is confirmed by using the receiver operating characteristic curves; meanwhile, the superiority of the CD-LEG-FET platform is found to present a methylation panorama of the target gene.

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A light addressable potentiometric sensor (LAPS) is a versatile sensing platform for bioassay. However, the lack of carbon-based LAPS (C-LAPS) is a bottleneck for its sustainable development in a carbon electronic era. Herein, a study of C-LAPS based on the combinations of carbon dots (CDs) and liquid exfoliated graphene (LEG) is presented. Devices of C-LAPS are first fabricated by self-assembling the hydrothermally synthesized CDs and the cosolvent ultrasonic delaminated LEG on poly(diallyldimethylammonium chloride) (PDDA)-modified indium tin oxide (ITO) glasses. According to the stacking orders of CDs and LEG, C-LAPS are named as CDs/LEG@PDDA/ITO and LEG/CDs@PDDA/ITO. Then, their electronic and photoelectronic features are measured and compared with the pure CD-and pure LEG-decorated ITO electrodes. Furthermore, working mechanisms are proposed by means of the classical theories of energy band bending and built-in electric field at the heterojunction of CDs and LEG. The resemblances of CDs/LEG@PDDA/ITO-based C-LAPS with Si-based LAPS (Si-LAPS) are confirmed from the points of view of production and separation of the photogenerated carriers, the formation of photocurrent, and the distinction with LEG/CDs@PDDA/ITO. Finally, its feasibility for biological application is justified by using the immune reaction of 5-methylcytosine (5mC) and its antibody (anti-5mC) as a proof of concept. The improved linear responses are evidenced by the comparisons with Si-LAPS' results. Conclusively, the proposed C-LAPS is believed to be a candidate for traditional semiconductor-based LAPS, with the merit of solutionprocessable. Meanwhile, the theoretical deductions about C-LAPS' principle can also pave the way for developing similar carbonbased sensors.

Ferula sinkiangensis K. M. Shen is a valuable traditional Chinese medicine historically used to treat stomachache and rheumatoid arthritis. The chloroplast genome of Ferula genus plant has not been previously reported. This study reported the complete chloroplast genome sequence of F. sinkiangensis based on high-throughput sequencing. The genome was 166,583 bp in length, containing a small single-copy (SSC) region of 17,595 bp and a large single-copy (LSC) region of 85,242 bp, separated by two inverted repeats (IRs) of 31,873 bp, each. The genome contained 114 unique genes, including 80 protein-coding genes (PCGs), four rRNA genes, and 30 tRNA genes. In addition, 17 genes contained one or two introns, including nine PCG genes with a single intron, two PCG genes harboring two introns, and six tRNA genes harboring a single intron. In this study, F. sinkiangensis K. M. had the closest genetic relationship with Torilis scabra and clustered with the Umbelliferae family species.

Building a map of the environment is a prerequisite for mobile robot navigation. In this paper, we present a semantic map building method for indoor navigation of a robot using only the image sequence acquired by a monocular camera installed on the robot. First, a topological map of the environment is created, where each key frame forms a node of the map represented as visual words (VWs). The edges between two adjacent nodes are built from relative poses obtained by performing a novel pose estimation approach, called one-point RANSAC camera pose estimation (ORPE). Then, taking advantage of an improved deformable part model (iDPM) for object detection, the topological map is extended by assigning semantic attributes to the nodes. Extensive experimental evaluations demonstrate the effectiveness of the proposed monocular SLAM method.