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Titanium base alloys can be used as potential candidate of structural materials in nuclear reactor due to their outstanding corrosion resistance and mechanical properties. By using molecular dynamics (MD) methods, this paper simulated the displacement cascade processes in α-Ti metal at various temperatures (T=300, 500, 700 and 900 K) with primary knock-on atom (PKA) (EPKA=1, 5, 10 and 20 keV) incident in various directions ([0001], [1010] and [1100]). The displacement cascades were designed as follows, the model was initially relaxed at each specified temperature for 10 ps with periodic boundary conditions applied. Then, a PKA was randomly selected and assigned specific kinetic energy to initiate the displacement cascade. At length, the data production, defect analysis and visualization were done to elucidate the irradiation cascade processes. The results show that the defect number increases with the increase of PKA energy or temperature, whereas the incident directions of PKA does not affect the defect number during the evolution a lot. With the increase of temperature, the number of peak defects in α-Ti increase significantly, and the time required for the defect recombination process extends. With the increase of PKA energy, the number of defect in the entire defect evolution process increases significantly, and the steady-state defect number also shows an increasing tendency. However, the PKA incident direction has slightly effect on the defect evolution during the cascade process. The Norgett-Robinson-Torrens (NRT) model was used to calculate the trendency of defect number as functional of PKA energy and it is consistent with the MD calculations. Considering the simulated temperature and PKA energy, and the number of remaining defects after cascade collision accounted for about 30% of NRT. The results in this paper help to understand the primary irradiation defect and atomic effect evolution mechanisms in α-Ti from the perspective of theoretical calculations. Moreover, discussing how to enhance the radiation resistance of metallic titanium and titanium alloys under the current theoretical research content has certain guiding significance for the design of future nuclear reactor shell materials.

Objective To observe the effects of amarogentinon liver cancer stem cells (LCSCs) after insufficient thermal ablation and its mechanism. Methods A insufficient thermal ablation model of HepG2 cells was established by water bath method.The percentage of CD133-positive LCSCs and the mRNA and protein levels of CD133 were detected by flow cytometry, qRT-PCR and Western blot.The insufficient thermal ablation model of HepG2 cells was treated with variable doses of amarogentin for 24 h; the percentage of CD133-positive LCSCs, the proliferation and apoptosis of liver cancer cells, and the mRNA and protein levels of CD133, TBC1D15, and p53were detected by flow cytometry, qRT-PCR and Western blot. Results The percentage of CD133-positive HepG2 cells and the mRNA and protein levels of CD133 and TBC1D15in the insufficient thermal ablation model were significantly higher than those in the normal HepG2 cells.Amarogentin then markedly decreased the percentage of CD133-positive LCSCs, the proliferation rate of HepG2 cells, and the mRNA and protein levels of CD133 and TBC1D15 in the insufficient thermal ablationresidual model (all P < 0.05);inversely, the apoptosis rate of HepG2 cells and the phosphorylated levels of p53 in the insufficient thermal ablation model were significantly increased (all P < 0.05). Conclusion Amarogentin could reduce the proportion of LCSCs after insufficient thermal ablation, inhibit the proliferation, and promote the apoptosis of LCSCs, which maybe associated with increasing the phosphorylation of p53 and inhibiting the expression of TBC1D15.

BackgroundNickel-, iron- and tungsten-based alloys are commonly used as structural materials of reactors. During their operational life, these alloys undergo intense neutron irradiation.PurposeThis study aims to analyze the post-irradiation defect evolution and its mechanisms in these materials for comprehending the effects of irradiation on them.MethodsThe displacement cascades in nickel, iron, and tungsten were examined at various temperatures (300⁓500 K), primary knock-on atom (PKA) energies (, and ) by using molecular dynamics (MD) simulations. Firstly, the model was initially relaxed at each specified temperature under a canonical ensemble for 10 ps, applying periodic boundary conditions in every direction. Then, an atom was randomly chosen as a PKA and assigned kinetic energy to initiate the cascade collision simulation in the micro-canonical ensemble. Finally, the Open Visualization Tool package was employed for visualization and data analysis of the irradiation cascade processes.ResultsThe simulation results reveal that nickel and iron exhibit similar steady-state defects. At lower PKA energies (

In order to improve the desorption of coal methane by the sonic vibration of cavitation water jets, aiming at overcoming the weakness of originally developed simulation test platform, an experimental cavitation chamber and its coal shaping device have been improved and redesigned. Using the technologies of omnidirectional sealing,such as ring direction and surface sealing,etc.,a good sealing result of triaxial pressure chamber and cavitation chamber for a long time under confining pressure and 5 MPa gas pressure is obtained. Using Venturi nozzle and high-pressure jet device in the cavitation chamber, the cavitation bubble cloud formed in the cavitation chamber enhances the desorption of coal methane. With the installation of pressure sensor at water inlet and outlet, the cavitation effect is monitored in real time. Depending on the temperature and methane pressure sensor, extensometer and the supporting test control software, the permeability characteristics of methane desorption of coal sample under gas pressure and the evolution laws of stress-strain process of coal sample during sonic vibration process can be simulated. The temperature in the cavitation chamber and the variation of gas seepage during sonic vibration process can be monitored in real time. In addition, three-phase separator is designed in the recycle system, and the test maneuverability is improved. The feasibility of separating gas-liquid-solid matters via this separator is realistically proved. The simulation experiments using the improved experimental device show that the sonic vibration of cavitation water jets improves the desorption of coal methane, gas desorption quantity and desorption speed. The variation of temperature in the cavitation chamber and the deformation laws of coal sample verify the thermal effects of sonic vibration, the effects of mechanical vibration and crack damage. [ABSTRACT FROM AUTHOR]

Objective: To analyze adenovirus-mediated endosome lysis of T cells, we developed a novel approach based on pHrodo dextran (pH-sensitive fluorescent dye)., Methods: After incubating Jurkat cells (T cell leukemia) with serotype 5 adenovirus (Ad5) and pHrodo dextran, we determined the optimal incubation time and concentration of pHrodo dextran. To assess viral lysis of the endosome, we monitored the ratio changes of mean fluorescence intensity in different time points by laser scanning confocal microscopy., Results: After incubating Jurkat cells with Ad5 and 80 μg/mL pHrodo dextran for 10 minutes, we observed the fluorescence intensity was significantly reduced at 30 minutes compared with that of endosomes at 0 minute. However, we found the mean fluorescence intensity was only slightly reduced by inhibiting V-ATPase with the bafilomycin A1 treatment., Conclusion: The method based on pH-sensitive dye can be used to analyze the adenovirus-mediated endosome lysis of T cells.

Objective: To test a novel gene carrier, named polyethyleneimine nanogel particles (PEI-NP), for delivering the mircroRNA (miRNA) into Kupffer cells (KCs) for silencing the expression of nuclear transcription factor κB (NF-κB) P65., Methods: The capacity of PEI-NPs to carry miRNA was tested by gel electrophoresis. RAW264.7 cell line was transfected with the cationic polymers which mixed together PEI-NP and miRNA. Then, the cytotoxicity of the RAW264.7 cells was detected by cell counting kit-8 (CCK-8); the cell apoptosis and transfection efficiency were analyzed by flow cytometry combined with annexin V-FITC/PI staining; the gene and protein levels of NF-κB P65 were determined respectively by real-time quantitative PCR (qRT-PCR) and Western blotting. The distribution of the cationic polymers in RAW264.7 cells and liver KCs was observed by transmission electron microscope (TEM). The protein level of NF-κB P65 in KCs was detected by immunohistochemistry., Results: PEI-NPs were able to completely combine with miRNA at the least mass ratio of 20:1. The highest transfection efficiency of 48 hours was (33.63±1.94)% in vitro. The protein level of NF-κB P65 at 48 hours of PEI-NP/miRNA transfection into RAW264.7 cells was significantly inhibited. TEM showed the cationic polymers in RAW264.7 cytoplasm and only in KCs of liver tissue after transfection. Immunohistochemistry indicated that the protein expression of NF-κB P65 in KCs was significantly lower than that in control group., Conclusion: Macrophages and KCs were successfully transfected with the cationic polymers in vitro and in vivo, respectively. The expression of NF-κB P65 was knocked down significantly after transfection.

The research on intracellular trafficking of adenovirus has been described mainly through observations of subgroup C adenoviruses in transformed cell lines. The basic elements of the trafficking pathway include binding to receptors at the cell surface, internalization by endocytosis, lysis of the endosomal membrane, escape to the cytosol, intracellular trafficking along microtubules, nuclear pore docking, and viral genome translocation into the nucleus. More than 80% of the adenovirus genome is delivered to the nucleus in a highly efficient manner in approximately 1 h. However, exceptions to this trafficking pattern have been noted, including: variations based on target cell type, cell physiology, and adenovirus serotype. This review summarizes mechanism of adenovirus infection pathway and intracellular trafficking, providinging a foundation for the development of clinical adenoviral vector.

Objective: To investigate the characteristics of ultrasonography in haemophilic arthropathy in knee joints., Methods: The knee joints (n=135) of 68 patients with haemophilia A (n=59) or haemophilia B (n=9) were consecutively evaluated with ultrasonography and scored according to MELCHIORRE ultrasound score. The correlations between ultrasound score and the number of knee joint bleeding episodes, age, and World Federation Haemophilic orthopedic (WFHO) score were studied., Results: 68 male patients with median age 20 (3-48) years old were enrolled in this study. The prevalences of hydrops articuli, fibrotic septa, synovial hypertrophy, synovial hypertrophy with angiogenesis, haemosiderin deposition were 39.2% (53/135), 3.0% (4/135), 77.0% (104/135), 49.6% (67/135), 37.8% (51/135), respectively; and the prevalences of cartilage damage, bone erosion, bone remodeling, osteophytes were 63.7% (86/135), 48.1% (65/135), 3.0% (4/135), 13.3% (18/135) respectively. The average ultrasound score was 5.21[95% CI (4.50-5.93)]. The ultrasound score of knees joints according to age 0-6, 7-18 and > 18 years old groups were 0.63[95% CI (0.15-1.10)], 2.88[95% CI (1.90-3.85)], 7.83[95% CI (7.07-8.60)], respectively; and the difference among groups was statistically significant (P<0.01). The significant difference of ultrasound score was not found among moderate, mild and severe haemophilia (F=0.90, P=0.914). A significant positive correlation between ultrasound and WFHO scores was demonstrated (r=0.745, P<0.01). The ultrasound score increased significantly with the increase of number of knee bleed Episodes (F=49.926, P<0.01)., Conclusion: The main characteristics of ultrasonography of haemophilic arthropathy in knee joints were identified as followings: synovial hypertrophy, cartilage damage, bone erosion, hydrops articuli, and haemosiderin deposition. Ultrasonography was a fast, effective, safe, and available inspection method in assessment of haemophilic arthropathy.

Objective: To report 4 methods of reconstructing soft tissue defects in oral and maxillofacial regions after tumors resection using cervical pedicle tissue flaps., Methods: One hundred seventy-two soft tissue defects were repaired with cervical myocutaneous flaps after resection of oral and facial cancer (165 cases of squamous cell carcinoma and 7 cases of salivary carcinoma). The clinical stage of the tumors was stage I in 21 cases, stage II in 116 cases and stage III in 35 cases. Primary sites of the lesions were the tongue (59 cases), buccal mucosa (55 cases), lower gingiva (26 cases), floor of the mouth (25 cases), parotid gland (4 cases) and oropharynx (3 cases). Infrahyoid myocutaneous flaps were used in 60 cases, platysma flaps in 45 cases, sternocleidomastoid flaps in 59 cases and submental island flaps in 8 cases. The sizes of skin paddle ranged from 2.5 cm x 5.0 cm to 5.0 cm x 8.0 cm., Results: Among 153 survival flaps, there were 55 infrahyoid myocutaneous flaps, 40 platysma flaps, 52 sternocleidomastoid flaps and 6 submental island flaps. There were 11 cases of total flap necrosis and 8 cases of partial flap necrosis. The success rates were 91.67% (55/60) for infrahyoid myocutaneous flap, 88.89% (40/45) for platysma flap, 88.14% (52/59) for sternocleidomastoid flap and 75% (6/8) for submental island flap. After a follow-up of 3 11 years (5.7 years on average) among 101 cases local recurrence in 18 cases, cervical recurrence in 4 cases, distance metastasis in 2 cases. The survival rate at 3 years were 83.17% (84/101)., Conclusion: Cervical pedicle tissue flaps have clinical value in reconstruction of small and medium-sized soft tissue defects after resection of oral and maxillofacial tumors.