Learning-Based Slip Detection for Robotic Fruit Grasping and Manipulation under Leaf Interference.

Robotic harvesting research has seen significant achievements in the past decade, with breakthroughs being made in machine vision, robot manipulation, autonomous navigation and mapping. However, the missing capability of obstacle handling during the grasping process has severely reduced harvest success rate and limited the overall performance of robotic harvesting. This work focuses on leaf interference caused slip detection and handling, where solutions to robotic grasping in an unstructured environment are proposed. Through analysis of the motion and force of fruit grasping under leaf interference, the connection between object slip caused by leaf interference and inadequate harvest performance is identified for the first time in the literature. A learning-based perception and manipulation method is proposed to detect slip that causes problematic grasps of objects, allowing the robot to implement timely reaction. Our results indicate that the proposed algorithm detects grasp slip with an accuracy of 94%. The proposed sensing-based manipulation demonstrated great potential in robotic fruit harvesting, and could be extended to other pick-place applications.

Ropivacaine inhibits proliferation, migration, and invasion while inducing apoptosis of glioma cells by regulating the SNHG16/miR-424-5p axis.

BACKGROUND: Regional anesthesia has anti-proliferative and pro-apoptotic effects in various cancers. Therefore, the purpose of this study was to investigate the effects of ropivacaine on the proliferation, migration, invasion, and apoptosis of glioma cells in vitro. METHODS: Under ropivacaine stimulation conditions, proliferation, apoptosis, migration, and invasion of glioma cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazol-3-ium bromide (MTT), flow cytometry, and transwell assays, respectively. Western blot assay was employed to measure the protein expression levels in glioma cells. The expression levels of small nucleolar RNA host gene 16 (SNHG16) and miR-424-5p were assessed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The interaction relationship between SNHG16 and miR-424-5p was predicted and confirmed using a bioinformatics database and dual-luciferase reporter, RNA immunoprecipitation (RIP) and RNA pull-down assays. RESULTS: After treatment with ropivacaine, proliferation, migration, and invasion were repressed while apoptosis was enhanced in glioma cells in a dose-depended manner. In addition, ropivacaine impeded SNHG16 expression in glioma cells. Importantly, overexpression of SNHG16 abolished the ropivacaine-induced effects on glioma cells. Analogously, knockdown of miR-424-5p counteracted the function of ropivacaine in glioma cells. We also found that SNHG16 bound to miR-424-5p and negatively regulated miR-424-5p expression in glioma cells. The rescue experiments indicated that ropivacaine might regulate glioma progression by targeting the SNHG16/miR-424-5p axis. CONCLUSION: Our findings revealed the anti-tumor effects of ropivacaine in glioma by targeting the SNHG16/miR-424-5p axis. These data might extend the understanding of regulatory mechanisms by which ropivacaine could suppress glioma development.

[A survey of Japanese encephalitis antibody migrant workers in Shenzhen 2009].

OBJECTIVE: To understand the immunological status of Japanese encephalitis (JE) antibodies amongst migrant workers and to provide epidemiological basis for public health strategies on JE prevention and control in Shenzhen. METHODS: A multi-stage random sampling method was used, and 1003 migrant workers aged 18 to 60 from 44 factories were investigated and their serum specimens were collected. The enzyme-linked immunosorbent assay (ELISA) was used to detect JE antibodies qualitatively. RESULTS: The gross IgG seroprevalence rate for JE was 20.2% (203/1003). Sex-specified seroprevalence was 21.2% (103/485) for male and 19.3% (100/518) for female, respectively (χ(2) = 579, P > 0.05). Age-specific seropositive rates were 22.6% (12/53) for those below 20 years old, 18.7% (120/642) for those between 20-years old, 26.0% (58/223) for those between 30-years old and 15.3% (13/85) for those on or above 40 years old (χ(2) = 7.96, P > 0.05). Proportions for self-reported positive immunization, non-immunization and unclear immunization history were 22.1% (30/136), 22.1% (51/231) and 19.2% (122/636), respectively (χ(2) = 501, P > 0.05). Seroprevalence by region of origins showed that workers from Guangdong province was the highest (30.5%, 50/164), followed by workers from Guangxi (29.7%, 22/74) whilst workers from Shan(3)xi (5.4%, 2/37) had the lowest rate. Seroprevalence rate for managers (29.0%, 31/107) was higher than that of technicians (7.1%, 1/14) (χ(2) = 21.78, P < 0.05). Serological positive rate of workers with university or above educational background was the highest (32.7%, 16/49), followed by that for individuals with college degree (10.3%, 10/97) (χ(2) = 13.02, P < 0.05). CONCLUSION: No associations are detected between JE seroprevalence and age, or sex, or self-reported immunization histories amongst migrant labor workers in Shenzhen. However, correlations between JE serological positive rate and region of origins, occupation and educational attainment are found to be significant. The gross seroprevalence of JE antibodies suggests that the level of JE antibodies amongst Shenzhen migrant workers is low and the population immunity barrier has yet to be established. It is necessary to strengthen prevention and control strategies of JE among labor workers of Shenzhen.

[A 1:2 matched case-control study on congenital external malformation during perinatal period].

OBJECTIVE: To investigate the risk factors for congenital external malformation. METHODS: A 1:2 matched case-control study was conducted with 52 cases of congenital external malformation during perinantal period collected from surveillance in Baoan District of Shenzhen City from January to June in 2000. RESULTS: Simple and multiple conditional logistic regression analysis showed that the major risk factors for congenital external malformations during perinatal period were preterm labor (beta(k) = 1.4171, s(theta, beta(kappa)) = 0.4601, OR = 4.115), adverse mental stimulus (beta(kappa) = 2.1870, s(theta beta(kappa)) = 0.7873, OR = 8.909), taking medicine (beta(k) = 1.9178, s(theta beta(kappa)) = 0.8072, OR = 6.808) and exposure to hazardous chemicals during early pregnancy (beta(k) = 0.9602, s(theta beta(kappa)) = 0.4262, OR = 2.612). CONCLUSIONS: Congenital external malformation during perinatal period was caused by multiple risk factors and results of the study showed that environmental and mental factors were in obvious connection with its occurrence.