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Insight into the seepage patterns of fluid flow within fractured rocks can lead to a better understanding of many challenging issues, such as oil or gas exploitation, heat extraction from hot dry rock (HDR), and controlling water inflow through cement grouting. However, these can only be assessed via some macroscopic phenomena like inlet or outlet flow properties or numeral simulation with synthetic rock fractures. This situation is because the real-time seepage diffusion features within rock fractures cannot be directly observed via conventional techniques, including the CT scanning technique, even if the colored solution is used as a developer. Therefore, we remove the obstacles that prevent fluid flow visualization within rock fractures by developing a transparent rock replica, and introducing Particle Image Velocity (PIV) technology. In addition to overcoming the opacity of rock, this method can help analyze the distribution patterns of velocity and vorticity fields, as well as the main seepage path by capturing the migration of particles and the fluid flow. The results show that the fluid transports along the low part of the rough fractures. Meanwhile, the flow direction is less affected by the fracture geometry if the flow rate exceeds a certain value. When the number of vortices on the fractures increases, they are mainly distributed in areas with large surface fluctuations. Interestingly, the maximum vorticity first grows slowly and then increases rapidly with increasing pumping rates. This study contributes to a more comprehensive understanding of the seepage patterns of fluid flow within rock fractures and their related engineering applications. Highlights: Based on PIV technology, a set of visual test equipment for seepage in rock fractures is developed. The distribution information of velocity vector, flow field and vorticity field on rock fractures can be obtained in real time. The digital extraction of fracture surface of rock samples is realized. [ABSTRACT FROM AUTHOR]

In order to improve the strength of the composite folding inflatable flexible wing cover of unmanned plane, the lay-up of the cover of honeycomb sandwich structure is optimized and designed by adopting multi-objective wolf colony algorithm. Aimed at the characteristic of discretization of the optimal variable of composite structure, multi-objective wolf colony algorithm with integer coding method was adopted and fitness function is proposed. Constraint condition was given by referring to the lay-up principle of composite. Multi-objective wolf colony algorithm based on population density was adopted for the optimization of algorithm module. Then the strategy of using the evaluation of estimate of the above simulation module to optimize the surface structure of the folding inflatable flexible wind was adopted. Non-dominated ranking and diversity of population density was introduced in algorithm MOWCA to maintain the operation, which effectively improved the front distribution diversity and convergence precision. The experimental result verifies the effectiveness of scheduling algorithm in multi-objective optimization. [ABSTRACT FROM AUTHOR]

Several years ago, in quantum mechanics, Davies proposed a method to calculate particle's traveling time with the phase difference of wave function. The method is convenient for calculating the sojourn time inside a potential step and the tunneling time through a potential hill. We extend Davies' non-relativistic calculation to relativistic quantum mechanics, with and without particle-antiparticle creation, using Klein-Gordon equation and Dirac Equation, for different forms of energy-momentum relation. The extension is successful only when the particle and antiparticle creation/annihilation effect is negligible. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of sodium copper chlorophyllin (SCC) on the proliferation, differentiation and immunomodulatory function of mesenchymal stem cells (MSCs) from mice with aplastic anemia. Methods: A mouse model of aplastic anemia was established by exposure of BALB/c mice to sublethal doses of 5.0 Gy Co60 γ radiation, followed by transplantation of 2×10 lymph node cells from DBA/2 donor mice within 4 h after radiation. Aplastic anemic BALB/c mice were randomly divided into six groups: the treated groups, which received 25, 50, or 100 mg/kg/day SCC, respectively; a positive control group treated with cyclosporine A (CsA); and an untreated model control group (model group); while, the non-irradiated mice as the normal control group. SCC or CsA were administered by gastrogavage for 20 days, starting on day 4 after irradiation. Peripheral blood cells were counted and colony-forming fibroblasts (CFU-F) in the bone marrow were assayed. The ability of MSCs to form calcium nodes after culture in osteoinductive medium was also observed. The immunosuppressive effect of MSCs on T lymphocytes was analyzed by enzyme-linked immunosorbent assay and flow cytometry, to evaluate the efficacy of SCC in mice with aplastic anemia. Results: Peripheral blood white cell and platelet counts were increased by medium and high SCC doses, compared with the untreated control. CFU-Fs were also increased compared with the untreated control, and the numbers of calcium nodes in MSCs in osteoinductive medium were elevated in response to SCC treatment. The percentage of Forkhead box protein 3 (FOXP3) T cells was increased in T cell-MSC cocultures, and the cytokine transforming growth factor β1 was up-regulated in SCC-treated groups. Conclusion: The results of this study suggest that SCC not only promotes the proliferation and differentiation of MSCs, but also improves their immunoregulatory capacity in mice with aplastic anemia. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of Panax notoginseng saponins (PNS) on the proliferation and differentiation in NIH3T3 cells. Methods: NIH3T3 cells were treated by various concentrations of PNS 0, 0.05, 0.10, 0.20, and 0.40 g/L. The vitality and proliferation potential of cells were detected by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, the alkaline phosphatase (ALP) activity was measured by p-nitrophenyl phosphate (pNPP) assay, and the mineralization formation ability was tested for the cellular differentiation toward osteoblast, as well as the expression level of phosphorylated extracellular signal-regulated kinase1/2(P-ERK1/2), extracellular signal-regulated kinase1/2 (ERK1/2) protein kinase was analyzed by Western blot with total cell lysate of NIH3T3 cells treated by PNS. Results: Both MTT and pNPP assay showed that optical density (OD) values were increased in response to PNS treatment at a dose-dependent pattern. The mineralization formation ability was enhanced in PNS-treated NIH3T3 cells compared with untreated cells. Meanwhile, the expression level of P-ERK1/2 protein kinase was up-regulated in PNS-treated NIH3T3 cells, while, the expression level of ERK1/2 protein kinase revealed no obvious difference with or without PNS treated cells. Conclusion: PNS could pay a role to promote the proliferation and differentiation in NIH3T3 cells by means of up-regulation of P-ERK1/2 protein kinase. [ABSTRACT FROM AUTHOR]

Abstract  NADH:ubiquinone oxidoreductase (complex I ) of the mitochondrial respiratory chain catalyzes the transfer of electrons from NADH to ubiquinone coupled to proton translocation across the membrane. The cDNA sequence of Dunaliella salina mitochondrial NADH: ubiquinone oxidoreductase 19-kD subunit contains a 682-bp ORF encoding a protein with an apparent molecular mass of 19 kD. The sequence has been submitted to the GenBank database under Accession No. EF566890 (cDNA sequences) and EF566891 (genomic sequence). The deduced amino-acid sequence is 74% identical to Chlamydomonas reinhardtii mitochondrial NADH:ubiquinone oxidoreductase 18-kD subunit. The 19-kD subunit mRNA expression was observed in oxygen deficiency, salt treatment, and rotenone treatment with lower levels. It demonstrate that the 19-kD subunit of Complex I from Dunaliella salina is regulated by these stresses . [ABSTRACT FROM AUTHOR]

Aim: To investigate the effects of panax notoginosides (PNS) on the proliferation of human hematopoietic stem/progenitor cells, and to explore the signaling pathway of the nuclear transcription factor of the glucocorticoid receptor (GR-NTF) initiated by PNS related with the proliferation. Methods: The human CD34+ cells and bone marrow nuclear cells were exposed to PNS at a concentration of 0,10,25, 50, and 100 mg/L, respectively, in semi-solid culture system to observe colony forming unite of all lineages, granulocyte, erythrocyte, and megakaryocyte (CFU-GEMM, CFU-GM, CFU-E, and CFU-MK). Three lineages of human hematopoietic cell lines, including granulocytic HL-60, erythrocytic K562, megakaryocytic CHRF-288, and Meg-01 cells were incubated with PNS at 20 mg/L for 14 d. Meanwhile, dexamethasone (Dex) was used as a positive control. The nuclear protein of the cells was analyzed by Western blotting with monoclonal antibodies against the amino or carboxyl terminus of GR-NTF. Electrophoretic mobility shift assay performed by using the 32P-radiolabeled GR-NTF consensus oligonucleotide. Results: PNS promoted the proliferation of CD34+ cells and significantly raised the colony numbers of CFU-GEMM by 34.7%±16.0% over the non-PNS control (P<0.01). PNS also enhanced the proliferation of CFU-GM, CFU-E, and CFU-MK by 39.3%± 5.7%, 33.3%±7.3%, and 26.2%±3.2%, respectively. GR-NTF protein levels of either the amino or carboxyl terminus in K562, CHRF-288, and Meg-01 treated by PNS increased by 2.4- 2.8 fold and 1.3- 3.9 fold over the untreated cells. GR-NTF binding activity, initiated by either PNS or Dex, was apparently elevated to form the complex of GR-NTF with DNA as higher density bands in K562 and CHRF-288 cells, and some activity appeared as a band in HL-60 cells induced by PNS. Conclusion: PNS displayed the action of hematopoietic growth factor-like or synergistic efficacy to promote proliferation of human progenitor cells, may play a role in the upregulation of gene expression related to proliferation of hematopoietic cells through increasing the GR-NTF synthesis and its DNA binding activity. [ABSTRACT FROM AUTHOR]