Rectangular illumination method using LED arrays for machine vision.

Machine vision image quality is significantly affected by illumination. Uniform illumination of a rectangular target surface requires a function for evaluating the illumination system. In this study, based on an LED array light source illuminance model, such an evaluation function was established. Further, the influence of the light source's structure on illumination was analyzed using a single-factor analysis method to determine the boundary conditions, and it was then solved using a genetic algorithm to finalize the structural design. An experimental platform was built to measure the illuminance uniformity. The experimental results were consistent with the numerical results, verifying the effectiveness and feasibility of the proposed illumination method. Thus, this research provides a theoretical reference for the illumination of a rectangular target surface for vision-based detection.

miR-497 promotes the migration and invasion of human medulloblast Daoy cell line through targeted regulation of ARHGDIA in vitro.

OBJECTIVES: To further investigate the effects of miR-497 on the biological behavior of human medulloblastoma cell line in vitro. METHODS: Human medulloblastoma cell lines, Daoy and D341, were used in this study, and the miR-497 expression in the cells was measured by Quantitative PCR with fluorescence. The Daoy cells were divided into the mimics group (Daoy cells treated with mimics), inhibitor group (Daoy cells treated with inhibitor), normal Daoy cells, ARHGDIA siRNA group (Daoy cells transfected with ARHGDIA siRNA), ARHGDIA control group (Daoy cells did not receive any treatment), and negative control group (normal cells transfected with ARHGDIA siRNA). The expression of miR-497 and ARHGDIA mRNA was measured by Quantitative PCR with fluorescence, while the level of ARHGDIA protein was measured by Western blot. The binding capability of ARHGDIA and miR-497 was assessed by luciferase assay, the migration of cells was assessed by wound healing assay, and the invasion of cells was assessed by Transwell assay. RESULTS: Compared to D341 cells, the miR-497 level was significantly higher in the Daoy cells (P < 0.01). The dual-luciferase reporter assay showed that miR-497 targets ARHGDIA. Transfecting the normal Daoy cells with miR-497 mimics significantly reduced the expression of ARHGDIA protein (P < 0.05), while transfecting normal Daoy cells with miR-497 inhibitor significantly increased the expression of ARHGDIA protein (P < 0.05). Consequently, the migration and invasion capability of cells increased significantly after transfection with miR-497 mimic (P < 0.05), and decreased significantly after transfection with miR-497 inhibitor (P < 0.05). In addition, the migration and invasion capabilities of the cells also increased significantly after transfection with ARHGDIA siRNA (P < 0.05). CONCLUSIONS: miR-497/ARHGDIA axis participates in the in vitro migration and invasion of human medulloblastoma cell lines.

[Effect of long noncoding RNA SPRY4-IT1 on proliferation and metastasis of medulloblastoma].

OBJECTIVE: To investigate the effects of long non-coding RNA SPRY4-IT1 (LncRNA) on proliferation and metastasis of medul-loblastoma cells. METHODS: SPRY4-IT1siRNA and control fluorescence siRNA were transfected into medulloblastoma cell line Daoy with Lipo-fe ctamine 2000 and were divided into control group and si-SPRY4-IT1 group. Relative expression of SPRY4-IT1 mRNA were detected by real-time quantitative PCR. The change of cell proliferation were examined using CCK-8 kit and clone forming experiment. The change of cell inva-sion and metastasis were examined by matrigel invasion assay and cell metastasis experiment respectively, The expression of matrix metallopro-teinase MMP-2 and MMP-9 were detected by Western blot. RESULTS: In si-SPRY4-IT1 group,the SPRY4-IT1 mRNA expression level, cell pro-liferation in vitro,cell invasion and migration ability, MMP-2 protein expression were significantly lower than those in the control group. CONCLUSIONS: Interference SPRY4-IT1 expression has prominent inhibitory effect on the cell proliferation、invasion and metastasis of medulloblastoma cell line Daoy.

[The relationship between hypermethylation of Syk gene promoter and medulloblastoma cell invasion and metastasis].

OBJECTIVE: To investigate the effect of demethylation of Syk gene promoter by the methylation transferase inhibitor 5-aza-CdR on the invasion and metastasis of medulloblastoma cell line Daoy. METHODS: Medulloblastoma cell line Daoy was treated with 5-aza-CdR in vitro. Methylation-specific PCR, real time-PCR and Western blot were used to detect Syk gene promoter methylation status, Syk mRNA and protein expression respectively. Transwell was employed to study the invasion and metastasis of medulloblastoma cell line Daoyby counting the cells that had invaded through Matrigel and migrated to the undersurface of the membrane before and after treatment of 5-aza-CdR. RESULTS: In comparison to control group, Syk gene promoter of 5-aza-CdR-treated groups was demethylated and expression of Syk mRNA and protein was significantly up-regulated by 3.40±0.24 folds (P<0.01) and 3.23±0.19 folds (P<0.01) respectively. The invasiveness and metastasis of medulloblastoma cell line Daoy was decreased(P<0.05). CONCLUSIONS: Hypermethylation of Syk gene promoter is responsible for the down-regulation of Syk gene expression in medulloblastoma cell line Daoy, which may be one of the mechanisms that enhanced cell invasion and metastasis. While 5-aza-CdR can reverse the hypermethylation of Syk gene promoter and restore Syk gene expression and thus suppresses invasiveness and metastasis of tumor cells.

Variable range hopping conductivity and spin glass behavior in spin-ladder Ba0.6K0.4Fe2Se3 single crystals.

Ba0.6K0.4Fe2Se3 (BKFS) single crystals were investigated by means of measurements of powder x-ray diffraction, temperature-dependent resistivity, anisotropic dc magnetization, ac magnetic susceptibility and specific heat. The powder x-ray diffraction indicates staggered iron displacements along the ladders with short and long Fe-Fe bond lengths (2.64(2) and 2.91(2) Å) variation. The resistivity of BKFS exhibits variable range hopping behavior with ln(ρ) ~ T(-1/2) at low temperature. The magnetic susceptibility χ(T) exhibits a sharp cusp at around 20 K in a zero-field-cooled process. The frequency-dependent ac magnetic susceptibility reveals that the cusp feature is attributable to spin glass behavior. The anisotropic ac magnetic susceptibility indicates that BKFS is probably an anisotropic Heisenberg-like spin glass with its easy magnetization plane perpendicular to the chain direction. The specific heat also supports an insulating and spin glass ground state. Extended Curie-Weiss behavior above 40 K was observed with a reduced effective moment (µ(eff) = 1.66 µ(B)/Fe for H is perpendicular to b and µ(eff) = 1.82 µB/Fe for H is parallel to b) in BKFS, which is close to the spin-only magnetism with S=1/2.

[The expression and significance of apoptosis related gene BAG-1 in meningioma].

OBJECTIVE: To analyze the expressions of BAG-1 in meningioma for further understanding of biological behaviors of meningiomas. METHODS: The specimens included in this study were collected from 158 meningioma cases. Streptavidin-peroxidase were used in immunohistochemical staining. The results of immunohistochemical score were depending on the positive ratio and intensity of the immunoreactivity. The expressions of BAG-1 in meningioma were analyzed in relationship with histopathologic grading, postoperative recurrence. RESULTS: The difference in the expression degree of BAG-1 between each subtype in the same histopathologic grade and various subtypes between the grade of II to III were not statically significant (P > 0.05). The expression degree of BAG-1 between each subtype in the pathological grade I to the each subtype pathological grade I or III was different, the difference had statistical significance (P < 0.05 or P < 0.01). The immunohistochemical score of the expression of BAG-1 was decreased gradually with the pathologic grading of WHO increased, and the result was statistically significant (chi2 = 141.49, P < 0.01). As the immunohistochemical score of the expression of BAG-1 decreased the postoperative meningioma was easy to recur, the result was statistically significant (x2 = 55.13, P < 0.01). CONCLUSION: The expression degree of BAG-1 is in close correlations with the WHO pathologic grading of meningioma. The lower the expressions of BAG-1, the more recurrent with postoperation of meningiomas will be.