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1.
ISA Trans ; 110: 172-197, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33097222

RESUMO

Initial positioning errors and the low adaptability of a priori digital elevation maps result in large positioning uncertainty intervals in the initial stage of terrain-aided navigation (TAN). This produces pseudo-peaks and mismatches in the initial position likelihood function and renders the convergence of the particle filter (PF) slow and unstable, while even causing divergence. Thus, the occurrence of the "kidnapped robot problem" is highly probable during the initial stage of TAN and is a scenario frequently faced by deep-sea and ultra-long-range underwater vehicles. In this study, a PF initialization method based on non-linear multi-terrain aided fusion position (NLMTP) is proposed to improve the stability and accuracy of TAN. NLMTP uses the terrain-aided position (TAP) information during the initial stage of TAN to estimate the high-precision probability distribution of the starting position via backward smoothing. Accordingly, a PF initialization method for non-Gaussian prior distribution probability is proposed to improve the convergence speed of the PF during the initial stage of underwater TAN. Finally, a performance comparison of PF initialized via the NLMTP, TAP confidence interval, and TERCOM methods was performed using the survey data obtained via onboard sensors. The experimental results show that NLMTP initialization improves the convergence speed and positioning accuracy of PF in the initial TAN phase; this improvement is clear in the low terrain-adaptability area.

2.
Chinese Journal of Geriatrics ; (12): 709-714, 2018.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-709340

RESUMO

Resveratrol is a non-flavonoid polyphenolic compound which presents in plants such as grapes.It has a variety of physiological effects such as antioxidant ,anti-inflammatory ,anti-cancer , cardiovascular and neurological protection. In cardiovascular disease ,through the anti-inflammatory , anti-oxidation and regulating a variety of factors ,resveratrol involves in atherosclerosis ,hypertension , ischemic heart disease ,heart failure and other cardiovascular disease process ,thus plays a protective function for heart. Related clinical researches are also widely carried out ,and resveratrol may be one of the candidate interventions for prevention and treatment of cardiovascular disease.

3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-615948

RESUMO

Objective To explore the mechanism that Staphylococcus aureus(S.aureus) α-toxin(Hla) regulate miR-142 expression and inhibit macrophage phagocytosis.Methods BALB/C mice and RAW264.7 cells were infected with wild type S.aureus(WT S.aureus),Hla deletion S.aureus(△HlaS.aureus) or phosphate buffered saline(PBS),and the expression level of miR-142 of skin tissues and cells were detected.miR-142 mimics and inhibitor were then applied in the RAW264.7 culture to examine the effect on phagocytosis.Direct targeting of miR-142 on protein kinase Cα(PKCα) was assessed by luciferase assay and western blotting.Results miR-142 expression in △HlaS.aureus group were significantly down-regulated than WT S.aureus group(P<0.05).MiR-142 mimics inhibited RAW264.7 phagocytosis ability and inhibitor enhanced RAW264.7 phagocytosis ability.PKCα was directly targeted by miR-142.MiR-142 mimics significantly decreased the mRNA expression levels of PKCα in RAW264.7 cells(P<0.05).Conclusion Hla could promote miR-142 expression in macrophages.MiR-142 could inhibit macrophage phagocytosis through down-regulated PKCα.

4.
The Journal of Practical Medicine ; (24): 1744-1747, 2015.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-467622

RESUMO

Objective To design and construct a controlled adenovirus vector in degradating by itself after induction for solving the problem of stimulating host immune and producing replication adenovirus and providing a secure exogenous gene vectors for clinical practice. Methods Based on the traditional adenovirus vector AdEasyTM system, we inserted the Cre gene which belongs to Cre-LoxP system into the downstream of Tet-On inducible expression system. Two LoxP sites were inserted into two sides of the shuttle plasmid′s right arm genome. Then, the full-length human insulin gene was inserted HindIII enzyme site. After the recombinant adenovirus infected the rat bone marrow-derived mesenchymal stem cells , fluorescent protein expression and insulin secretion were detected before or after induction by Dox. Results A new controlled recombinant adenovirus vector carrying human insulin gene was constructed successfully, and was named AdEasyN/INS. After the transfection of this new vector into QBI-293A cells and rat bone marrow mesenchymal stem cells , green fluorescent protein could be observed. After induction by Dox, both of the ratio of fluorescent cells/total cell and the levels of insulin significantly decreased. Conclusion Construction and preliminary validation of a controlledrecombinant adenovirus vector carrying human insulin gene is constructed successfully , it could infect rat bone marrow mesenchymal stem cells, and degradate by itself after Dox induction, realize the controllability of exogenous gene carrier.

5.
Chinese Journal of Dermatology ; (12): 285-287, 2008.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-400997

RESUMO

Objective To investigate the expressions of transforming growth factor beta receptors (TGF beta R), receptor-activated Smads and common-partner Smad in condylomata acuminata. Methods Tissue samples were collected from 20 patients with condylomata acuminata and 15 normal human controls.EliVisionTM plus immunohistochemical technique was used to detect the distribution and expression of TGF beta R Ⅰ , TGF beta R Ⅱ, Smad1/2/3, phosphorylated Smad2/3 and Smad4 in condylomata acuminata and normal control skin. Results Positive immunohistochemical staining for TGFbeta R Ⅰ , TGFbeta R Ⅱ,Smad1/2/3, p-Smad2/3 and Smad4 was detected in the epidermis of normal control skin. The intensity of im-munohistochemical staining was significantly lower for TGFbeta R Ⅰ , TGFbeta R Ⅱ, Smad1/2/3, p-Smad2/3and Smad4 in the epidermis of condylomata acuminata than in that of normal control skin (P < 0.05 or < 0.01). Conclusion The expressions of TGF beta R, receptor-activated Smads and common-partner Smad are decreased or absent in the epidermis of condylomata acuminata, which might interfere with TGF be-ta/Smad signaling and contribute to the development of epidermal hyperplasia in condylomata acuminata.

6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-563140

RESUMO

Objective To observe the biological activity of the recombinant immunotoxin hIL-2-LuffinP1 derived by gene engineering in vitro.Methods To observe the inhibitory effect on lymphocytes in vitro,the splenocytes isolated from C57 and BALB/c mice were used for mixed mouse lymphocyte response(MLR),and the lymphocyte proliferation was observed in vitro with BALB/c mice splenocytes stimulated by concanavalin A(ConA).Different concentrations of hIL-2-LuffinP1 was added into the reaction system,with LuffinP1 adopted as control.3H-TdR incorporation assay was used to detect the effects of hIL-2-LuffinP1 on lymphocyte proliferation,and its effects on CTLL-2 cells(IL-2 dependent cells) were also observed.The experiments consisted of six groups(PBS,IL-2,LuffinP1,LuffinP1+IL-2,hIL-2-LuffinP1 and hIL-2-LuffinP1+IL-2).CTLL-2 cells were cultured for 12h after being treated with different agents,and then the cells were stained by trypan blue to estimate the dead cells in every 100 cells.Results It was showed that CPM declined correspondingly to the gradually increased concentration of hIL-2-LuffinP1,and cell proliferation was inhibited obviously.The inhibition rate was up to 97% at the concentration of 10-6mmol/L of hIL-2-LuffinP1.The activity of inhibiting lymphocyte proliferation was proportional to the dosage.On the contrary,no obvious inhibition to lymphocyte proliferation was found in the control group treated with LuffinP1,the inhibition ratio only reached to 14% with the same concentration of hIL-2-LuffinP1.It was also found that,when hIL-2-LuffinP1 and LuffinP1 in different concentrations added to spleen cells stimulated by ConA,hIL-2-LuffinP1 still exhibited strong ability of inhibition on the splenocyte proliferation,while LuffinP1 has no obvious inhibiting effect on the lymphocyte proliferation in the two reaction systems mentioned above.MLR showed the same results.Furthermore,in the experiment of cytotoxic effects of IL-2-LuffinP1 on CTLL-2 cells,the inhibition rates of hIL-2-LuffinP1+IL-2 group and hIL-2-LuffinP1 group were 29.6% and 47.4% respectively,the difference was significant compared with IL-2 group(P

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