2D LiDAR SLAM Back-End Optimization with Control Network Constraint for Mobile Mapping.

Simultaneous localization and mapping (SLAM) has been investigated in the field of robotics for two decades, as it is considered to be an effective method for solving the positioning and mapping problem in a single framework. In the SLAM community, the Extended Kalman Filter (EKF) based SLAM and particle filter SLAM are the most mature technologies. After years of development, graph-based SLAM is becoming the most promising technology and a lot of progress has been made recently with respect to accuracy and efficiency. No matter which SLAM method is used, loop closure is a vital part for overcoming the accumulated errors. However, in 2D Light Detection and Ranging (LiDAR) SLAM, on one hand, it is relatively difficult to extract distinctive features in LiDAR scans for loop closure detection, as 2D LiDAR scans encode much less information than images; on the other hand, there is also some special mapping scenery, where no loop closure exists. Thereby, in this paper, instead of loop closure detection, we first propose the method to introduce extra control network constraint (CNC) to the back-end optimization of graph-based SLAM, by aligning the LiDAR scan center with the control vertex of the presurveyed control network to optimize all the poses of scans and submaps. Field tests were carried out in a typical urban Global Navigation Satellite System (GNSS) weak outdoor area. The results prove that the position Root Mean Square (RMS) error of the selected key points is 0.3614 m, evaluated with a reference map produced by Terrestrial Laser Scanner (TLS). Mapping accuracy is significantly improved, compared to the mapping RMS of 1.6462 m without control network constraint. Adding distance constraints of the control network to the back-end optimization is an effective and practical method to solve the drift accumulation of LiDAR front-end scan matching.

[Effect of Xinfeng Capsule on Beclin1/PI3K-AKT-mTOR of Adjuvant Arthritis Rats].

Objective To observe expression levels of autophagy related 5,7,12 mRNA (Atg5, 7,12), microtubule-associated protein 1 light chain 3 (LC3-II), Beclin1, phosphatidylinositol 3-kinase (PI3K) , protein kinase B (AKT) , mammalian target of rapamycin (mTOR) , IL-1 ß, TNF-α, IL-4, and IL- 10 in adjuvant arthritis (AA) rats, and effects of Xinfeng Capsule (XFC) on them. Methods Totally 48 male SD rats were divided into 4 groups, i.e., the control group, the model group, the Western medicine (WM) group (leflunomide, 5. 0 mg/kg) , the Chinese medicine (CM) group (Xinfeng Capsule, 3.0 g/kg) , 12 in each group. Thirty days after medication body weight (BW) , toe swelling degree (E%) , arthritis in- dex (AI) , and pathological changes of ankle joint and ultrastructural changes were observed. mRNA ex- pressions of Atg5, 7, 12, protein expressions of LC3-L , Beclin1 , PI3K, AKT, mTOR, serum contents of IL-1 ß, TNF-α, IL-4, and IL-10 were detected. Results Compared with the normal group, E%, Al, IL-1 ß and TNF-α increased; BW, levels of IL-4 and IL-10, mRNA expressions of Atg5 and Atg12, protein ex- pressions of LC3-ll and Beclin1 decreased (P <0.01, P <0.05), protein expressions of PI3K, AKT, mTOR increased (P<0.01) in the model group. Compared with the model group, E%, Al, mRNA expres- sions of IL-1ß , TNF-α-, and Atg12, protein expressions of PI3K, AKT, and mTOR decreased (P <0.01, P<0.05), IL-4, IL-10, protein expressions of LC3-II and Beclinl increased (P <0.01, P <0.05) in the two medicated groups. Atg5 mRNA expression decreased (P <0.01) , Atg7 mRNA expression increased (P < 0.05) in the WM group. Compared with the WM group,BW, IL-4, mRNA expressions of Atg5 and Atg12, protein expressions of PI3K and mTOR increased in the CM group (P <0.01 , P <0. 05). Conclusions The level of autophagy in AA rats was decreased, leading to excessive proliferation of synovial cells, swollen joints, elevated proinflammatory factors, decreased inflammatory factors, resulting in inflamma- tory reactions of joints. XFC could improve Al, toe swelling degree, and expressions of synovium autoph- agy related genes and proteins.

[Effect of Xinfeng Capsule on AS Patients and Their Serum Immunoglobulin Subtypes and Peripheral Lymphocyte Autophagy].

OBJECTIVE: To observe the effect of Xinfeng Capsule (XFC) on ankylosing spondylitis (AS) patients' symptoms and signs, serum immunoglobulin levels, peripheral blood lymphocyte autophagy protein, autophagy gene, and to explore its mechanism. METHODS: Totally 59 AS patients were assigned to the treatment group (39 cases) and the control group (20 cases) according to random digit table. Patients in the treatment group received XFC, 0.5 g each pill, three pills each time, 3 times per day, while those in the control group received sulfasalazine (SASP), 0.25 g per tablet, 4 tablets each time, twice per day. Three months consisted of one therapeutic course. Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Bath Ankylosing Spondylitis Functional Index (BASFI) were statistically calculated. Serum immunoglobulins (IgG1, IgG2, IgG3, IgG4, IgA , SIgA, and IgM) were detected using ELISA. Changes of Beclin1, LC3-II, phosphatidylinositol 3-kinase (PI3K), Akt, the mammalian target of rapamycin (mTOR) were detected using Western blot. Serum autophagy related genes such as Atg1, Atg5, Atg12, Atg13, and Atg17 were detected using the polymerase chain reaction (PCR). The correlation between immunoglobulin subtypes and autophagy gene in AS patients using Spearman correlation. RESULTS: Compared with before treatment, BASDAI, IgG1, lgG3, and IgA decreased (P < 0.01); PI3K, Akt, and mTOR protein expressions decreased (P < 0.01); ATG1, ATG12, ATG13, and ATG17 mRNA expressions decreased, ATG5 mRNA expression increased (P < 0.01) in the treatment group. But BASDAI, IgG1, and IgA levels decreased (P < 0.05, P < 0.01); PI3K, Akt, and mTOR protein expressions decreased (P < 0.05); ATG1 and ATG13 mRNA expressions decreased (P < 0.05, P < 0.01) in the control group. Compared with the control group, BASDAI, IgG1, and IgA levels decreased (P < 0.05); PI3K, Akt, mTOR protein expressions decreased (P < 0.01); ATG12 and ATG17 mRNA expression decreased, ATG5 mRNA expression increased (P < 0.01) in the XFC group. Correlation analysis showed AS patients' IgG1, IgG2, IgG3, IgA, SIgA, IgM had negative correlation with ATG17; IgG4 and ATG17 were positively correlated (P < 0.05, P < 0.01). CONCLUSION: XFC could elevate clinical efficacy of AS patients and enhance their autophagy, which might be achieved by acting on PI3K/Akt/mTOR signal, affecting autophagy gene and autophagy protein expression, taking part in the regulation of proliferation and differentiation of lymphocyte B, and strengthen humoral immunity.

Xinfeng capsule improves pulmonary function in ankylosing spondylitis patients via NF-ΚB-iNOS-NO signaling pathway.

OBJECTIVE: To study changes in the nuclear factor-κB p65 (NF-κB p65)-inducible nitric oxide synthase (iNOS)-nitric oxide (NO) signaling pathway and the effects of Xinfeng capsules (XFC) in patients with ankylosing spondylitis (AS). METHODS: One hundred twenty patients with AS were randomly divided into an XFC group and a Salazopyrin group. Sixty health subjects were included as a normal control group. In the two treatment groups, pulmonary functional parameters, forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), maximal voluntary ventilation (MVV), peak expiratory flow (PEF), forced expiratory flow at 25% of forced vital capacity (FEF25), forced expiratory flow at 50% of forced vital capacity (FEF50), and forced expiratory flow at 75% of forced vital capacity (FEF75) were determined. Enzyme linked immunosorbent assays were used for detection of the serum oxidative stress indexes, NF-κB p65, iNOS, NO, reactive oxygen species (ROS), reactive nitrogen species (RNS), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), total antioxidative capacity (TAOC) and interleukin-4 (IL-4), IL-10, IL-1ß, and tumor necrosis factor-α (TNF-α) contents. Westergren's method was used for determination of erythrocyte sedimentation rate (ESR). High-sensitivity C-reactive protein (Hs-CRP) was detected with a 7060 full-automatic biochemical analyzer (Hitachi, Japan). RESULTS: The clinical therapeutic effect in the XFC group was significantly superior to that in the Salazopyrin group (P < 0.01). Compared with the normal control group, FEV1, MVV, PEF, FEF50, FEF75, SOD, CAT, TAOC, IL-4, IL-10 were significantly lower, and NF-κB p65, iNOS, NO, ROS, RNS, MDA, IL-1ß, TNF-α, ESR, and Hs-CRP significantly higher in patients with AS (P < 0.01 or P < 0.05). Compared with before treatment, FEV1, MVV, PEF, FEF50, FEF75, SOD, CAT, TAOC, IL-4, and IL-10 were significantly increased, and NF-κB p65, iNOS, NO, ROS, RNS, MDA, IL-1ß, TNF-α, ESR, CRP, visual analog scales (VAS), Bath ankylosing spondylitis disease active index, Bath ankylosing spondylitis functional index, and Bath ankylosing spondylitis global index significantly decreased in the two treatment groups after treatment (P <. 0.01 or P < 0.05), with significant differences between the XFC and Salazopyrin groups (P < 0.01 or P < 0.05). Spearman correlation analysis indicated that FEV1, MWVV, PEF, FEF50, and FEF75 were positively correlated with SOD, CAT, TAOC, IL-4, and IL-10, and were negatively correlated with NF-κB p65, iNOS, NO, ROS, RNS, MDA, IL-13, TNF-α, ESR, and CRP. CONCLUSION: Patients with AS have local pathologic changes in the spinal cord and other joints. They also have decreased pulmonary function, which is negatively correlated with the NF-κB-iNOS-NO signaling pathway, oxidative indexes, and inflammatory factors. XFC improves rigidity and pain in spinal joints and other symptoms, laboratory indexes, and pulmonary function. The mechanism is possibly related to inhibition of the NF-KB-iNOS-NO signaling pathway.

[Role of Notch-Jagged/Delta signaling pathway in arthritis rats of reduced lung function induced by adjuvant].

OBJECTIVE: To observe the changes of pulmonary function and Notch signaling pathway of lung tissues in adjuvant-induced arthritis rats, and to investigate the mechanism of reduced lung function. METHODS: A total of 30 rats were randomly divided into a normal group and a model group. Rats in the model group were induced to establish the adjuvant arthritis AA model by intradermally injecting 0.1 mL Freund's complete adjuvant into the right paw. After 30 days, we observed the paw edema volume, arthritis index, pulmonary function, histomorphology, and Notch receptor/ligand of the lung tissue. RESULTS: Compared with the normal group, the paw edema volume, arthritis index, average expiratory flow within 0.3 s (FEV0.3/FVC), and the level of Notch3, Notch4 and Jagged2 of the lung tissue in the model group was significantly increased, while maximum expiratory flow at 50% of vital capacity (FEF50), maximum expiratory flow at 75% of vital capacity (FEF75), forced expiratory flow (PEF) and the expression of Notch1 of Jagged1 and Delta1 in the lung were significantly decreased (P<0.05, P<0.01). There were significant positive correlations between FEV0.3/FVC and Notch4. FEV0.3/FVC, FEF25, FEF50 and Notch3, Delta1 were negatively correlated, respectively (P<0.05, P<0.01). CONCLUSION: While arthritis occurs in AA rats, pulmonary function declines and significantly correlates with the expression of Notch receptor/ligand. The deposition of immune complex in the lung after the injection of CFA activates the Notch signaling pathway, and results in further decline of pulmonary function by signaling cascades.

[Regional cerebral oxygen saturation in neonates with meconium aspiration syndrome].

OBJECTIVE: This study examined the changes of regional cerebral oxygen saturation (rSO2) by noninvasive near infrared spectrophotometry in neonates with meconium aspiration syndrome (MAS). METHODS: Seventy-three full neonates with MAS were divided into three groups by respiratory symptoms: asymptomatic group (group 1, n=38), common group (group 2, n=28) and severe group (group 3, n=7). Near infrared spectrophotometry was used to measure the cerebral rSO2 on days 1, 3, 5 and 7 after birth. Thirty healthy full-term newborns served as the Control group. RESULTS: The cerebral rSO2 of group 1 decreased significantly compared with that of the Control group between days 1 and 3 (P < 0.05). The cerebral rSO2 of group 2 or group 3 was significantly lower than that of group 1 and the Control group on days 1, 3 and 5 (P < 0.05). The MAS patients with mild hypoxic-ischemic encephalopathy (HIE) had significantly higher brain rSO2 levels than those with medium or severe HIE on days 2, 3 and 5 (P < 0.05). CONCLUSIONS: The cerebral rSO2 decreased in neonates with MAS. The values for rSO2 correlated with the severity of HIE in MAS patients.