Motion blur processing method for visual SLAM system based on local residual blur discrimination network

Jiahao Chen,Yehu Shen,Qixin Zhu,Quansheng Jiang,Ou Xie,Jing Miao 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.7

In visual simultaneous localization and mapping (vSLAM) systems, motion blur often leads to insufficient number of matched features, resulting in tracking failure. Existing solutions often tackle this problem by restoring sharp images from blurry ones. However, the computational costs are high, and the restored sharp images are usually distorted. The effect of blurry image sequences to vSLAM system is analyzed, and the relationships between feature matching and motion blur are acquired to deal with the above mentioned problems. A local residual motion blur discrimination network is proposed to detect images with motion blur efficiently. Motion blur recognition results are coupled with a vSLAM system so that the feature extraction process is guided by the results from the local residual motion blur discrimination network. The performance of the vSLAM system can be effectively enhanced when it is applied to sequences with motion blur. Experimental results on the Technische Universität München dataset show that the proposed algorithm increases the average tracking length by about 200 frames compared with the original method on some image sequences with violent motions. This algorithm effectively improves the stability and accuracy of the vSLAM system.

Comparative Genomic and Genetic Functional Analysis of Industrial L-Leucine- and L-Valine-Producing Corynebacterium glutamicum Strains

( Yuechao Ma ),( Qixin Chen ),( Yi Cui ),( Lihong Du ),( Tuo Shi ),( Qingyang Xu ),( Qian Ma ),( Xixian Xie ),( Ning Chen ) 한국미생물생명공학회(구 한국산업미생물학회) 2018 Journal of microbiology and biotechnology Vol.28 No.11

Corynebacterium glutamicum is an excellent platform for the production of amino acids, and is widely used in the fermentation industry. Most industrial strains are traditionally obtained by repeated processes of random mutation and selection, but the genotype of these strains is often unclear owing to the absence of genomic information. As such, it is difficult to improve the growth and amino acid production of these strains via metabolic engineering. In this study, we generated a complete genome map of an industrial L-valine-producing strain, C. glutamicum XV. In order to establish the relationship between genotypes and physiological characteristics, a comparative genomic analysis was performed to explore the core genome, structural variations, and gene mutations referring to an industrial L-leucine-producing strain, C. glutamicum CP, and the widely used C. glutamicum ATCC 13032. The results indicate that a 36,349 bp repeat sequence in the CP genome contained an additional copy each of lrp and brnFE genes, which benefited the export of L-leucine. However, in XV, the kgd and panB genes were disrupted by nucleotide insertion, which increase the availability of precursors to synthesize L-valine. Moreover, the specific amino acid substitutions in key enzymes increased their activities. Additionally, a novel strategy is proposed to remodel central carbon metabolism and reduce pyruvate consumption without having a negative impact on cell growth by introducing the CP-derived mutant H+/citrate symporter. These results further our understanding regarding the metabolic networks in these strains and help to elucidate the influence of different genotypes on these processes.

Does the Access Angle Change the Risk of Approach-Related Complications in Minimally Invasive Lateral Lumbar Interbody Fusion? An MRI Study

Huang, Chunneng,Xu, Zhengkuan,Li, Fangcai,Chen, Qixin The Korean Neurosurgical Society 2018 Journal of Korean neurosurgical society Vol.61 No.6

Objective : To investigate the potential risk of approach-related complications at different access angles in minimally invasive lateral lumbar interbody fusion. Methods : Eighty-six axial magnetic resonance images were obtained to analyze the risk of approach-related complications. The access corridor were simulated at different access angles and the potential risk of neurovascular structure injury was evaluated when the access corridor touching or overlapping the corresponding structures at each angle. Furthermore, the safe corridor length was measured when the corridor width was 18 and 22 mm. Results : When access angle was $0^{\circ}$, the potential risk of ipsilateral nerve roots injury was 54.7% at L4-L5. When access angle was $45^{\circ}$, the potential risk of abdominal aorta, contralateral nerve roots or central canal injury at L4-L5 was 79.1%, 74.4%, and 30.2%, respectively. The length of the 18 mm-wide access corridor was largest at $0^{\circ}$ and it could reach 44.5 mm at L3-L4 and 46.4 mm at L4-L5. While the length of the 22 mm-wide access corridor was 42.3 mm at L3-L4 and 44.1 mm at L4-L5 at $0^{\circ}$. Conclusion : Changes in the access angle would not only affect the ipsilateral neurovascular structures, but also might adversely influence the contralateral neural elements. It should be also noted to surgeons that alteration of the access angle changed the corridor length.

Comparative portrayal of ocular surface microbe with and without dry eye

ZhenHao Li,Yufang Gong,ShuZe Chen,SiQi Li,Yu Zhang,HuiMin Zhong,ZhouCheng Wang,YiFan Chen,QiXin Deng,YuTing Jiang,LiYing Li,Min Fu,GuoGuo Yi 한국미생물학회 2019 The journal of microbiology Vol.57 No.11

To compare the ocular surface (OS) microbial communities and diversity between dry eye (DE) and non-DE (NDE). Furthermore, we compared meibomian gland dysfunction (MGD) and non-MGD (NMGD) among DE subjects. The V3-V4 region of 16S rRNA gene high-throughput sequencing was performed in the conjunctival swab samples to investigate the composition of the OS bacterial community in DE (n=35) and NDE (n=54) and compared the composition of MGD (n=25) and NMGD (n=10) among DE subjects. Deep sequencing of OS 16S rDNA from DE (n=35) and NDE (n=54) demonstrated great a difference in alpha and beta diversity between the OS bacterial flora (P < 0.05). The similar OS microbial structures were shown at the phylum and genus levels by bioinformatics analysis between them, and in LEfSe (linear discriminant analysis effect size) analysis, Bacteroidia and Bacteroidetes were enriched in DE, while Pseudomonas was plentiful in NDE (linear discriminant analysis [LDA] > 4.0). Among the DE group, there was no significant difference in α and β diversity between MGD and NMGD (P > 0.05). Surprisingly, Bacilli was the dominant microbe in MGD, and Bacteroidetes was the superior bacteria in NMGD among DE subjects (LDA > 4.0). Different diversity of OS bacteria composition between DE and NDE and the altered diversity of OS bacteria may play an important role in DE. Moreover, the lower dominance of OS bacteria in DE may be associated with the occurrence and development of DE. Although there was no significant difference in alpha and beta analysis, the OS dominant microbe between MGD and NMGD among DE was different.

Small Molecule-Based Strategy Promotes Nucleus Pulposus Specific Differentiation of Adipose-Derived Mesenchymal Stem Cells

Hua, Jianming,Shen, Ning,Wang, Jingkai,Tao, Yiqing,Li, Fangcai,Chen, Qixin,Zhou, Xiaopeng Korean Society for Molecular and Cellular Biology 2019 Molecules and cells Vol.42 No.9

Adipose tissue-derived mesenchymal stem cells (ADSCs) are promising for regenerating degenerated intervertebral discs (IVDs), but the low efficiency of nucleus pulposus (NP)-specific differentiation limits their clinical applications. The Sonic hedgehog (Shh) signaling pathway is important in NP-specific differentiation of ADSCs, and Smoothened Agonist (SAG) is a highly specific and effective agonist of Shh signaling. In this study, we proposed a new differentiation strategy with the use of the small molecule SAG. The NP-specific differentiation and extracellular matrix (ECM) synthesis of ADSCs were measured in vitro, and the regenerative effects of SAG pretreated ADSCs in degenerated IVDs were verified in vivo. The results showed that the combination of SAG and transforming growth factor-${\beta}3$ ($TGF-{\beta}3$) is able to increase the ECM synthesis of ADSCs. In addition, the gene and protein expression levels of NP-specific markers were increased by treatment with SAG and $TGF-{\beta}3$. Furthermore, SAG pretreated ADSCs can also improve the disc height, water content, ECM content, and structure of degenerated IVDs in vivo. Our new differentiation scheme has high efficiency in inducing NP-specific differentiation of ADSCs and is promising for stem cell-based treatment of degenerated IVDs.

Molecular Cloning, Characterization, and Expression Analysis of Chicken Δ-6 Desaturase

Kang, Xiangtao,Bai, Yichun,Sun, Guirong,Huang, Yanqun,Chen, Qixin,Han, Ruili,Li, Guoxi,Li, Fadi Asian Australasian Association of Animal Productio 2010 Animal Bioscience Vol.23 No.1

Long-chain polyunsaturated fatty acids (LC-PUFA) promote the development of brain and vision of the fetus, relieve inflammation, inhibit oral dysplasia of rumor cell, decrease the incidence of cardiovascular disease and regulate arrhythmia. ${\Delta}-6$ desaturase is the rate-limited enzyme in the desaturation process. This study reports the cloning, characterization and tissue expression of a ${\Delta}-6$ desaturase gene in the chicken. PCR primers were designed based on the predicted sequence of chicken ${\Delta}-6$ desaturase (accession number: XM421053) and used to isolate a cDNA fragment of 1,323 bp from chicken liver. Based on the 1,323 bp fragment an EST (BI390105) was obtained by BLAST. The EST and 5'nd of the 1,323 bp fragment were partially overlapped. Gene specific primers derived from the EST were used for amplification of the 5'nd. Another gene-specific primer derived from the 1,323 bp fragment was used for amplification of the 3'nd by 3'ACE. Then the three overlapping cDNA sequences obtained were assembled with DNAMAN software and a full-length ${\Delta}-6$ desaturase of 2,153 bp was obtained. The full-length cDNA contained an ORF of 1,335 bp with a 5'ntranslated region of 147 nucleotides followed by an ATG initiation codon. Stop codon TGA was at position 1,481-1,483 bp. The deduced amino acids shared an homology above 77% with bovine, mice, orangutan, rat and human. The protein sequence had three histidine-rich regions HDFGH (HisI region), HFQHH (HisII region) and HH (HisIII region), a cytochrome $b_{5}$-like domain containing a heme-binding motif and two transmembrane domains. Sequence analysis of the chicken genomic DNA revealed that the coding sequence of chicken ${\Delta}-6$ desaturase included 12 exons and 11 introns. Semi-quantitative RT-PCR showed that the ${\Delta}-6$ desaturase expression levels were in turn liver, spleen, pancreas, lung, breast muscle, heart, and abdominal fat. The expression of ${\Delta}-6$ desaturase in liver was significantly higher than that in breast muscle (p<0.01). The expression of ${\Delta}-6$ desaturase in lung was significantly higher than that in abdominal fat (p<0.01). This is the first clone of chicken ${\Delta}-6$ desaturase.

Small Molecule-Based Strategy Promotes Nucleus Pulposus Specific Differentiation of Adipose-Derived Mesenchymal Stem Cells

Jianming Hua,Ning Shen,Jingkai Wang,Yiqing Tao,Fangcai Li,Qixin Chen,Xiaopeng Zhou 한국분자세포생물학회 2019 Molecules and cells Vol.42 No.9

Adipose tissue-derived mesenchymal stem cells (ADSCs) are promising for regenerating degenerated intervertebral discs (IVDs), but the low efficiency of nucleus pulposus (NP)-specific differentiation limits their clinical applications. The Sonic hedgehog (Shh) signaling pathway is important in NP-specific differentiation of ADSCs, and Smoothened Agonist (SAG) is a highly specific and effective agonist of Shh signaling. In this study, we proposed a new differentiation strategy with the use of the small molecule SAG. The NP-specific differentiation and extracellular matrix (ECM) synthesis of ADSCs were measured in vitro, and the regenerative effects of SAG pretreated ADSCs in degenerated IVDs were verified in vivo. The results showed that the combination of SAG and transforming growth factor-β3 (TGF-β3) is able to increase the ECM synthesis of ADSCs. In addition, the gene and protein expression levels of NP-specific markers were increased by treatment with SAG and TGF-β3. Furthermore, SAG pretreated ADSCs can also improve the disc height, water content, ECM content, and structure of degenerated IVDs in vivo. Our new differentiation scheme has high efficiency in inducing NP-specific differentiation of ADSCs and is promising for stem cell-based treatment of degenerated IVDs.

Chemical, optical, and electrical characterization of Ga2O3 thin films grown by plasma-enhanced atomic layer deposition

Xing Li,Hong-Liang Lu,Hong-Ping Ma,Jian-Guo Yang,Jin-Xin Chen,Wei Huang,Qixin Guo,Jijun Feng,David Wei Zhang 한국물리학회 2019 Current Applied Physics Vol.19 No.2

Thin Ga2O3 films were grown on Si (100) using trimethylgallium (TMG) and oxygen as the precursors through plasma-enhanced atomic layer deposition. The depositions were made over a temperature range of 80–250 °C with a growth per cycle of around 0.07 nm/cycle. Surface self-saturating growth was obtained with TMG pulse time ≥20 ms at a temperature of 150 °C. The root mean square surface roughness of the obtained Ga2O3 films increased from 0.1 nm to 0.3 nm with increasing the growth temperature. Moreover, the x-ray photoelectron spectroscopy analysis indicated that the obtained film was Ga-rich with the chemical oxidation states Ga3+ and Ga1+, and no carbon contamination was detected in the films after Ar+ sputtering. The electron density of films measured by x-ray reflectivity varied with the growth temperature, increasing from 4.72 to 5.80 g/cm3 . The transmittance of Ga2O3 film deposited on a quartz substrate was obtained through ultraviolet visible (UV–Vis) spectroscopy. An obvious absorption in the deep UV region was demonstrated with a wide band gap of 4.6–4.8 eV. The spectroscopic ellipsometry analysis indicated that the average refractive index of the Ga2O3 film was 1.91 at 632.8 nm and increased with the growth temperature due to the dense structure of the films. Finally, the I-V and C-V characteristics proved that the Ga2O3 films prepared in this work had a low leakage current of 7.2 × 10−11 A/cm2 at 1.0 MV/cm and a high permittivity of 11.9, suitable to be gate dielectric.