Research on Properties of Silicone-Modified Epoxy Resin and 3D Printing Materials.

A kind of organosilicon intermediate was prepared using isophorone diisocyanate (IPDI), hydroxyl silicone oil (HSO), and hydroxyethyl acrylate (HEA). The organosilicon modification of epoxy resin was realized by introducing a -Si-O- group into the side chain of epoxy resin by chemical grafting. The effects of organosilicon modification of epoxy resin on the mechanical properties systematically discuss its heat resistance and micromorphology. The results indicate that the curing shrinkage of the resin was decreased and the printing accuracy was improved. At the same time, the mechanical properties of the material are enhanced; the IS and elongation at break (EAB) are enhanced by 32.8 and 8.65%, respectively. The brittle fracture is changed to a ductile fracture, and the tensile strength (TS) of the material is decreased. The glass transition temperature (GTT) of the modified epoxy resin increased by 8.46 °C, and T50% and Tmax increased by 1.9 and 6 °C, respectively, indicating that the heat resistance of the modified epoxy resin was improved.

Entropy Stable DGSEM Schemes of Gauss Points Based on Subcell Limiting.

The discontinuous Galerkin spectral element method (DGSEM) is a compact and high-order method applicable to complex meshes. However, the aliasing errors in simulating under-resolved vortex flows and non-physical oscillations in simulating shock waves may lead to instability of the DGSEM. In this paper, an entropy-stable DGSEM (ESDGSEM) based on subcell limiting is proposed to improve the non-linear stability of the method. First, we discuss the stability and resolution of the entropy-stable DGSEM based on different solution points. Second, a provably entropy-stable DGSEM based on subcell limiting is established on Legendre-Gauss (LG) solution points. Numerical experiments demonstrate that the ESDGSEM-LG scheme is superior in non-linear stability and resolution, and ESDGSEM-LG with subcell limiting is robust in shock-capturing.

Energy Stability Property of the CPR Method Based on Subcell Second-Order CNNW Limiting in Solving Conservation Laws.

This paper studies the energy stability property of the correction procedure via reconstruction (CPR) method with staggered flux points based on second-order subcell limiting. The CPR method with staggered flux points uses the Gauss point as the solution point, dividing flux points based on Gauss weights, with the flux points being one more point than the solution points. For subcell limiting, a shock indicator is used to detect troubled cells where discontinuities may exist. Troubled cells are calculated by the second-order subcell compact nonuniform nonlinear weighted (CNNW2) scheme, which has the same solution points as the CPR method. The smooth cells are calculated by the CPR method. The linear energy stability of the linear CNNW2 scheme is proven theoretically. Through various numerical experiments, we demonstrate that the CNNW2 scheme and CPR method based on subcell linear CNNW2 limiting are energy-stable and that the CPR method based on subcell nonlinear CNNW2 limiting is nonlinearly stable.

Bioactive components, antioxidant and antimicrobial activities of Paeonia rockii fruit during development.

In last ten years, much attention focused on tree peony fruit (TPF) for edible oil production despite other potential utilization. The present study identified and quantified 29 bioactive components by liquid chromatography-electrospray ionization-triple quadrupole-mass spectrometry (LC-ESI-QqQ-MS) targeted approach during the development of TPF. Trans-resveratrol, benzoic acid, luteolin, and methyl gallate were selected as predominant chemical markers between seeds and pods through principal component analysis (PCA) and orthogonal partial least square-discriminant analysis (OPLS-DA). Extremely high levels of paeoniflorin (1893 mg/100 g) and trans-resveratrol (1793 mg/100 g) were observed at stage 2 (S2) and S6 in seeds, respectively. Antioxidant activities determined by ABTS+•, DPPH•, and FRAP assays showed significant correlations with total phenolic content (TPC) and total flavonoid content (TFC). The strongest antibacterial effects of pod and seed against Staphylococcus aureus and Proteus vulgaris occurred at initial stages and maturation stages. TPF could be a potential source of bioactive compounds with functional properties.

New Insights into the Impact of Ecological Factor on Bioactivities and Phytochemical Composition of Paeonia veitchii.

Paeonia veitchii has been widely distributed in China under different ecological types. Its roots contain diverse phytochemical constituents, which possess very high bioactivities. However, the influence of ecological factors on activities and ingredients of P. veitchii roots still remains unknown. The purpose of this research was to analyze the variation in bioactivities and phytochemical composition of P. veitchii roots upon exposure to various ecological factors. Seven P. veitchii populations collected from different regions in China were evaluated. The results of correlation analysis suggested that four major ecological factors, including average annual temperature, elevation, total potassium, and organic matter, had a strong correlation with the bioactivities of P. veitchii roots. Further, the major ecological factors were also highly correlated with the contents of naringin, gallic acid, benzoylpaeoniflorin, and paeoniflorin. The principal component analysis results supported four major metabolites as the main contributing ingredients. All populations were classified into three groups, G1, G2, and G3, through hierarchical cluster analysis. G1 showed more significant advantages in the above-mentioned four ecological factors, four active ingredients, and bioactivities compared to the other two groups. P. veitchii roots growing at lower average annual temperature, high elevation, rich total potassium and organic matter in the soils were presumed to have relatively higher bioactivities. These data expand the study on the bioactivities and phytochemical composition of P. veitchii roots and have a guiding significance for the ecological factor selection during the cultivation process of this herbaceous peony species.

Phenotypic Characteristics and Fatty Acid Composition of Seeds from Different Herbaceous Peony Species Native to China.

Herbaceous peony has been widely cultivated in China due to its substantial ornamental and medicinal value. In the present study, the phenotypic characteristics, total fatty acid (FA) content, and nine FA compositions of herbaceous peony seeds from 14 populations belonging to six species and one subspecies were determined by normal test and gas chromatography/mass spectrometry (GC/MS). The results showed that the phenotypic characteristics of seeds varied dramatically among species. The concentrations of five major FAs in seed oils were as follows: linoleic acid (173.95-236.51 µg/mg), linolenic acid (227.82-302.71 µg/mg), oleic acid (135.32-208.81 µg/mg), stearic acid (6.52-11.7 µg/mg), and palmitic acid (30.67-47.64 µg/mg). Correlation analysis demonstrated that oleic acid had the highest partial correlation coefficient with total FAs and might be applied to develop a model of phenotypic characteristics. FAs were significantly influenced by the following environmental factors: latitude, elevation, and annual average temperature. Based on the FA levels in the seed oils, clustering analysis divided 14 populations into two clusters. It was found that the average contents of oleic acid, linoleic acid, and total FAs in cluster I (147.16 µg/mg, 200.31 µg/mg, and 671.24 µg/mg, respectively) were significantly lower than those in cluster II (196.65 µg/mg, 220.16 µg/mg, and 741.78 µg/mg, respectively). Cluster I was perfectly consistent with subsect. Foliolatae, while cluster II was in good agreement with subsect. Dissectifoliae. Therefore, the FA composition of wild herbaceous peony seed oil might be used as a chemotaxonomic marker.

[Study on force feedback of acupuncture at Fengchi (GB 20)].

Acupuncture manipulations on Fengchi (GB 20) of famous doctors were taken through force feedback device, then the data was input into a digitized virtual human. Virtual Fengchi (GB 20) acupuncture force feedback simulation system was built through the virtual reality technology to achieve one-to-one high simulative manipulation effect for acupuncture students. The interaction force of the needle body and human tissues was analyzed during the acupuncture process on the 3D digital human integrated with information of Fengchi (GB 20) according to the physical characteristics of the tissues under this point. The mechanical model which is used to imitate the stress received by the body of the needle was established, and transmitted truly to the operator by the force feedback device. Thus, Fengchi (GB 20) virtual acupuncture force feedback simulation was preliminary established, and the sense of touch could be reproduced lively on the visualized virtual acupuncture human. It is held that Fengchi (GB 20) acupuncture force feedback research is a preliminary exploration for virtual acupuncture that integrated with the information of visual, tactile and force feedback. And it also provided a dynamic one-to-one simulation approach for acupuncture teaching.

[Study on the angle and depth of needle insertion at Huantiao (GB 30) by three-dimensional reconstruction].

OBJECTIVE: To observe the anatomic structure of Huantiao (GB 30) visually, to imitate the inserting process of the needle to explore the safty of needle insertion and improve the therapeutic effect of acupuncture in clinic. METHODS: Combined with anatomic structure of acupoint, muscles and other tissues related with Huantiao (GB 30) were interactively segmented in VOXEL-MAN with the computer graphics technology. Nerves and blood vessels were reconstructed by establishing mathematic model, and the needle-inserting animation of Huantiso (GB 30) was obtained by running script file. RESULTS: The three-dimensional (3-D) visualization of Huantiao (GB 30) on needle-inserting animation was accomplished, the spatial location and expression of Huantiao (GB 30) in the digitized virtual human body were observed, the virtual inserting process was imitated realistically, and the 3-D animation of needle insertion at Huantiao (GB 30) was created. CONCLUSION: Building mathematic model is favorable for expressing the anatomic structure of Huantiao (GB 30) in 3-D space, imitating the process of needle insertion realistically and observing the spatial structure of the point and the around tissues, which can provide a solid foundation for the safety of needle insertion of acupoints and improve therapeutic effect of acupuncture in clinic.

[Meta-analysis of fibrin glue for attaching conjunctival autografts in pterygium surgery].

OBJECTIVE: To evaluate the clinical efficacy of FG for attaching conjunctival autografts in pterygium surgery. METHODS: Search was conducted in Pubmed, EMbase, Cochrane Library, CNKI, Wanfang database, CBM and VIP, and hand-search was also performed, the methodological quality were carried out according to evidence-based medicine (EBM). The qualities of the randomized controlled trials (RCT) were evaluated according to the Cochrane Handbook for Systematic Reviews of Interventions Version 5.0. The Cochrane Collaboration's software RevMan 5.0 was used for Meta-analysis. RESULTS: Only 7 trials, involving 366 eyes, were included. Meta-analysis showed that significant differences were found between the FG and suture in recurrence [RR = 0.34, 95%CI (0.15, 0.80), P = 0.01], but there is no difference in reducing the complications [RR = 2.53, 95%CI (0.47, 13.51), P = 0.28]. CONCLUSION: Fibrin glue-assisted conjunctival autograft in pterygium surgery reduces postoperative recurrence.

[The neuroglobin expression when retinal ganglion cells death in acute rats' retina ischemia].

OBJECTIVE: To investigate the intra-retinal expression of neuroglobin (Ngb) and death of retinal ganglion cells (RGCs) in acute retina ischemia rats. METHODS: It was an experimental study. The acute retina ischemia model was established by specific hypothesised left retina artery of Sprague-Dawley rats. Forty rats were divided into four groups (0, 15, 30, 60 min) by the time of retina ischemia. Every group has 10 rats, in one group random 3 rats were detected by Western blotting; 4 rats were detected by ganglion cell counted by hematoxylin and eosin stain and immunohistochemistry fluorescence intensity analysis. The rest 3 rats were detected by Western blotting. The difference among different data were analyzed statistically by One-factor analysis of variance and LSD-t analysis. RESULTS: The intra-retinal expression of Ngb reached maximum after acute ischemia 15 minute (P = 0.000). then the expression began decreasing. After 30 minute acute ischemia, the expression of Ngb had approached normal (P = 0.728), while, the cell number of RGCs began lower than 0 min group (P = 0.011); after 60 minute acute ischemia, the expression of Ngb had been obviously lower than 0 min group (P = 0.001), the cell number of RGCs had been further lower than 0 min group (P = 0.000). The expression of Ngb in RGCs layer was highest in rat retina. The expression in inner plexiform layer and external plexiform layer were lower than the former. The expression of Ngb RGCs was mostly intracytoplasm. After 30 minute acute ischemia, the expression of Ngb were detected in mitochondrial outer compartment and mitochondrial cristae, but in cytoplasm of inner nuclear layer and outer nuclear layer the Ngb was not found. CONCLUSION: Ngb quickly steps-up when RGCs die in acute retina ischemia, and mainly expresses intracytoplasm of RGCs. It has tense relationships with nerve cells' survival in hypoxia.

[Effect of Nogo-66 on retinal microglia in chronic ocular hypertension rats].

OBJECTIVE: To study the effect of protein Nogo-66 on the expression of CD11b and MHC-II in retinal microglia of chronic ocular hypertension SD rats and the effects of protein Nogo-66 on the immunogenicity of injured retinal tissues. METHODS: It was a control experimental study. Chronic ocular hypertension rat model was established by laser photocoagulation on the anterior chamber angle and superficial vein of the sclera. One ml of Nogo-66 (0.01%) in PBS was injected subcutaneously on the day of laser treatment and 0.005% Nogo-66 PBS solution was injected into the vitreous 7 days and 1 month latter. PBS without Nogo-66 was injected in the control group. The expression of cell surface antigen CD11b and MHC-II were detected by immunohistochemistry 1 month and 1 day after the establishment of hypertension model. The difference of average IOP among groups was analyzed by variance analysis. The difference of expression of CD11b and MHC-II between the experimental and control groups was analyzed by t-test. RESULTS: The intraocular pressure (IOP) of experimental groups rised from the seventh day after model-building and the highest IOP was (24.16 ± 2.70) mm Hg (1 mm Hg = 0.133 kPa) 1 month later while that in the control groups was (15.93 ± 3.28) mm Hg. The difference between them was statistically significant (F = 2.10, P < 0.05). Expression of CD11b was (1.78 ± 0.63)% and MHC-II was (3.92 ± 1.03)% in Nogo-66 with hypertension groups, these results was significantly lower than those in Nogo-66 with normal intraocular pressure groups in which the expression of CD11b was (8.15 ± 1.97)% (t = 2.35, P < 0.05) and MHC-II was (11.45 ± 1.97)% (t = 2.14, P < 0.05). CONCLUSIONS: Protein Nogo-66 activated the cell surface antigen CD11b in nerve fiber layer of retina and induced antigen presenting molecules (MHC-II). This indicates that Nogo has the center immunogenicity and this protein could activate antigen-presenting cells to present injury antigen.

[Study on force feedback of acupuncture manipulation at Jianliao (TE 14) based on VOXEL-MAN].

OBJECTIVE: To discuss the mechanical virtual reality when acupuncture on Jianliao (TE 14) so as to get perform perceptual knowledge of acupuncture for beginners through studying 3D reconstruction of surrounding tissues of this acupoint. METHODS: Related tissues were segmented and reconstructed by establishing mathematics model based on the operational platform of VOXEL-MAN (vision reappearance); and mechanical model was constructed and fused with related data of virtual human (touch reappearance); data communication between the force feedback apparatus and the operational platform of virtual human were set up by interchanging vision reappearance module and touch reappearance module. RESULTS: In Linux system, the operator could experience the mechanical changes while needle-tip passing various tissues of Jianliao (TE 14) as well as lifting and thrusting evenly in needling process through the force feedback apparatus. CONCLUSION: Based on the platform of VOXEL-MAN, the sensation of needling at jianliao (TE 14) could be reappeared idealy by strength feedback instrument, so that the beginners could imitate, learn and practice the virtual acupuncture.

[Expression of CD11b in the retinal microglia in chronic hypertension rat].

OBJECTIVE: To study the expression of CD11b in the retinal microglia in laser induced ocular hypertension (OHT) SD rat. METHODS: It was an experimental study. OHT was induced by the coagulation of trabecular meshwork using 532-laser in sixty SD rats. Intraocular pressure (IOP) was measured by Tonopen-XL, the expression of CD11b in retinal microglia detected by immunohistochemistry, and retinal ganglion cells (RGCs) were labeled with Dextran Tetramethyl Rhodamine (DTR) and counted by Image-Pro Plus Version 6.0 image analysis software at 2 weeks, 1, 2, 3, 4, 5, and 6 months, respectively. All the numerical data were statistically analyzed by SPSS 13.0 software. RESULTS: Although the IOP of experimental groups are still the similar level at 2w after coagulation (t = 1.124, P = 0.287), Compared to control eyes, IOP in lasered eyes was significantly (t = 2.487, P = 0.036) increased at 1 month, lasting for 3 months and returned to normal from 5 to 6 months (t = 1.103, P = 0.290). The expression of CD11b in the retinal microglia in the lasered eyes was significantly more intensive than that in control eyes at 1 month (t = 3.333, P = 0.008) and faded after 5 months, a similar pattern to IOP response, that two group data shows significant dependability (r = 0.891, P = 0.014). The number of RGC was significantly reduced from 1 month to 6 months (t = 3.316, P = 0.009), the velocity of reducing seems dependability to the advancing of IOP (r = 0.757, P = 0.021). CONCLUSIONS: The expression of CD11b in retinal microglia is fluctuated with chronic OHT pattern and RGCs injury level indicating that the injury antigens by microglia are presented in the retina with the increase of IOP and activate the immunologic process leading to glaucomatous RGCs damage. It suggests that it is important to effectively control the IOP in order to reduce the risk of immune induced retinal damage by microglia.

[Study on the visualization of the Lung Meridian of Hand-Taiyin].

OBJECTIVE: To display the Lung Meridian of Hand-Taiyin at the body surface in a virtual human. METHODS: After defining the acupoints as the control points, chose suitable function interpolation to compose skeleton curve, actualize surface rendering and to rebuild a tube-like meridian model. RESULTS: The rebuilt tubular meridian model had a good visual effect, and clearly showed different anatomic structures of the Lung Meridian of Hand-Taiyin. CONCLUSION: We primarily and successfully accomplish the visualization display of the Lung Meridian of Hand-Taiyin in a virtual human, which affords a data carrier for building a meridian research platform.

[Brief analysis on scientifity of the international scalp acupuncture].

By comparing and analyzing the similarity among the international scalp acupuncture, JIAO's scalp acupuncture and ZHU's scalp acupuncture, it is believed that the international scalp acupuncture is a combination of traditional acupuncture and other scalp acupuncture on the basis of channel theory of TCM, and this combination is worthy of discussion. However JIAO's scalp acupuncture lacks scientific evidence. So, the international scalp acupuncture following most contents of JIAO's scalp acupuncture is worthy of discussion.

[Preliminary study on force feedback of acupuncture in virtual reality based on the visible human].

This paper discusses the application of virtual reality technology in the 3-D visible human body and acupuncture research. Based on the 3-D visible human fused with the localization information and hierarchy of acupoints, the paper analyzes the force against the needle and haptic rendering during the needle manipulation according to the physical properties of different tissues. A haptic model is constructed to demonstrate the force behaviors during acupuncture, and the force will be produced and passed to the manipulator by a force feedback device. It enriches the contents of 3-D visible human project, provides a dynamic simulation instrument for acupuncture teaching, and supplies a platform for acupuncture research.

[Three-D visualization study on the acupoint of Jianliao (TE 14) based on the operational platform of Voxel-man].

OBJECTIVE: To discuss the problem difficult to be presented for nerves and blood vessels in the 3D reconstruction of acupoints through studying 3D reconstruction of Jianliao (TE 14). METHODS: Muscles and other tissues were segmented by applying cointeractive segmentation method based on chromatic characteristic space; the nerve and blood vessels can be reconstructed by establishing mathematics model, and the needle-inserting animation of Jianliao (TE 14) could be obtained by running script file. RESULTS: During the course of 3D needle-inserting animation of Jianliao (TE 14), the spatial location between all kinds of tissues including the nerve and blood vessels and the needle body could be systematically observed. CONCLUSION: The difficulty of presenting the nerve and blood vessels in the study on 3D reconstruction of acupoints can be resolved by establishing mathematics model. The generation of 3D animation for acupoints with the nerve and blood vessels is benefit to acupuncture teaching and study on the essence of acupoints and channels.

[Study on the visible display of Meridian on the dummy human body].

OBJECTIVE: To study on visible display of Meridian on the dummy human body. METHODS: Tube model-building method and computer technique were used, and data came from Voxel-Man dummy human body development platform. RESULTS: The visual effect of re-building Meridian is very good and it can display the different layers of anatomic structures on the Meridian lines. CONCLUSION: The visible display of Meridian on the dummy human body is preliminary realized, which provides data carriers for establishing the platform of Meridian study.

[Comparative experimental study on treatment of rat's injured sciatic nerve with electroacupuncture and Buyang Huanwu Decoction].

OBJECTIVE: To study the effect of the electroacupuncture and Buyang Huanwu Decoction (BYHWD) on the regeneration of the rat's injured sciatic nerve. METHODS: Rat's sciatic nerve injury model was made by operation. The rats were treated with electroacupuncture or BYHWD and their nerve electro-physiological indices and histological changes tested by HRP were observed. RESULTS: It was demonstrated that the recovery ratios of nerve conduction velocity and muscle evoked action potential of the group treated with electroacupuncture and the group treated with BYHWD were higher than those of the group treated with western medicine or the group without treatment. The differences were significant. The labeling cells in anterior horn of spinal marrow and spinal ganglion of the group treated with electroacupuncture and the group treated with BYHWD were more abundant than those of the group treated with western medicine or the group without treatment. The differences were significant. The effect of electroacupuncture was better than that of the BYHWD. CONCLUSION: It suggests that both electroacupuncture therapy and BYHWD can promote the recovery of the function in early stage of injured nerve, and they are effective methods for promoting the regeneration of injured peripheral nerve.