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We have employed the highly accurate multistate complete active space second‐order perturbation theory (MS‐CASPT2) method to investigate the photoinduced excited state relaxation properties of one unnatural base, namely Z. Upon excitation to the S2 state of Z, the internal conversion to the S1 state would be dominant. From the S1 state, two intersystem crossing paths leading to the T2 and T1 states and one internal conversion path to the S0 state are possible. However, considering the large barrier to access the S1/S0 conical intersection and the strong spin‐orbit coupling between S1 and T2 states (>40 cm−1), the intersystem crossing to the triplet manifolds is predicted to be more preferred. Arriving at the T2 state, the internal conversion to the T1 state and the intersystem crossing back to the S1 state are both possible considering the S1/T2/T1 three‐state intersection near the T2 minimum. Upon arrival at the T1 state, the deactivation to S0 can be efficient after overcoming a small barrier to access T1/S0 crossing point, where the spin‐orbit coupling (SOC) is as large as 39.7 cm−1. Our present work not only provides in‐depth insights into the photoinduced process of unnatural base Z, but can also help the future design of novel unnatural bases with better photostability. [ABSTRACT FROM AUTHOR]

The monopile is the most common foundation to support offshore wind turbines. In the marine environment, local scour due to combined currents and waves is a significant issue that must be considered in the design of wind turbine foundations. In this paper, a full-scale numerical model was developed and validated based on field data from Rudong, China. The scour development around monopiles was investigated, and the effects of waves and the Reynolds number Re were analyzed. Several formulas for predicting the scour depth in the literature have been evaluated. It is found that waves can accelerate scour development even if the KC number is small (0.78a) is proposed and validated with field data. The equilibrium scour depth predicted using the proposed equation is evaluated and compared with those from nine equations in the literature. It is demonstrated that the values predicted from the proposed equation and from the S/M (Sheppard/Melville) equation are closer to the field data. [ABSTRACT FROM AUTHOR]

Wetting-drying alternation irrigation (WDI) can harvest high grain yield under effective irrigation water saving conditions. However, the kernel cadmium (Cd) content usually exceeds the national standard of 0.20 mg Cd per kg kernel in WDI. Applying a passivating agent with high-efficient repairing capabilities could be a feasible approach to reduce Cd content lower than 0.20 mg·kg -1 in WDI. Therefore, a field experiment was conducted with different irrigation regimes and passivating agents in a mildly Cd-polluted paddy field, of which the irrigation regimes were WDI and traditional flooded irrigation (FI) and the six passivating agents treatments were CK (no passivating agent; T1), slaked lime with 1125 kg·hm -2 (T2), 1125 kg slaked lime and 3000 kg biochar per hectare (T3), 1125 kg slaked lime and 3000 kg organic fertilizer per hectare (T4), 1500 kg porous Nano stupalith per hectare (T5), and 1125 kg slaked lime combined with 1500 kg porous Nano stupalith per hectare (T6). Two typical Indica hybrid rice varieties with a high accumulated capacity named cultivar Shenliangyou 1813 and a low accumulated trait named cultivar Liangyou 6206 were utilized. The main reason that Indica hybrid rice cultivars were selected was their higher absorbed and accumulated characteristics than that of Japonica rice. The results indicated that available Cd content of the soil significantly declined with 17.13%-61.01% decreasing amplitude at maturity when compared with pre-transplanting in WDI; however, the reduction was in the range of -43.45%-21.07% for the FI treatment across cultivars and passivating agents treatments. The available Cd content at maturity was significantly greater in FI than in WDI ( P <0.05). In contrast, WDI had higher Cd content on stem, leaf, and kernel organs at maturity than with FI treatment of both cultivars and all of the passivating agents ( P <0.05). Generally, the T1 treatment had the maximum available Cd content in the soil layer and highest accumulated Cd content on different aboveground organs, followed by the T2, T3, T4, T5, and T6 treatments considering both cultivars and irrigation regimes. The Cd kernel contents were 0.23-0.24 mg·kg -1 and 0.16-0.21 mg·kg -1 for cultivars Shenliangyou 1813 and Liangyou 6206, respectively, in the T6 treatment. The higher Cd kernel content was generally related to a larger Cd content in the stem organ. For the grain yield, no significant differences were observed among cultivars, irrigation regimes, or passivating agents treatments ( P >0.05). Under WDI, the kernel Cd content was still slightly higher than 0.20 mg·kg -1 in the T6 treatment (0.24 mg·kg -1 for cultivar Shenliangyou 1813 and 0.21 mg·kg -1 for cultivar Liangyou 6206); however, there is a predictability potential to produce lower than 0.20 mg·kg -1 kernel content in the T6 treatment if a cultivar with low accumulated capacity is used. Thus, the combined mode of the WDI+T6+cultivar with accumulated low Cd content could be considered an optimized cultivation scheme to obtain no Cd contaminated kernels with high grain yield and water-use efficiency in mildly polluted paddy fields.

Aim: To explore the subpopulation of CD4(+); CD25(+); Foxp3(+); regulatory T cells (Treg), CD4(+); CD25(+); CD127(low/-); Treg in peripheral blood of HIV-infected patients and study its correlation with other immune indicators., Methods: We enrolled 68 cases of HIV/AIDS patients without anti-HIV treatment [29 cases of long-term non-progressive (LTNP) group, 27 cases of typical progressive HIV infection group and 12 cases of AIDS group] and 20 healthy individuals as a control group. Blood samples of these cases were analyzed by flow cytometry after immunofluorescent staining to determine the levels of CD4(+); T cells, CD8(+); T cells, NK cells and CD4(+); CD25(+); Foxp3(+);/CD127(low/-); Treg., Results: Except CD8(+); T cells, the levels of CD4(+); T, NK cells and CD4(+);/CD8(+); in peripheral blood of HIV/AIDS patients were significantly lower than those in the control group (P<0.05); With the progression of disease, the percentage and absolute count of CD4(+);T cells, the absolute counts of CD8(+);T cells and NK cells, and CD4(+);/CD8(+); T cell ratio in the LTNP group, HIV group and AIDS group decreased gradually, while the percentage of CD8(+);T cells increased gradually. Our multiple comparison analysis revealed that the percentages of CD4(+); CD25(+); Foxp3(+); Treg and CD4(+); CD25(+); CD127(low/-); Treg in CD4(+); T cells were significantly different among groups (P<0.05). With the progression of disease, the percentages of CD4(+); CD25(+); Foxp3(+); Treg and CD4(+); CD25(+); CD127(low/-); Treg increased gradually; in addition, the difference in the absolute count of CD4(+); CD25(+); Foxp3(+);/CD127(low/-); Treg was not statistically significant between LTNP group and healthy control group(P>0.05), so was between HIV and AIDS groups (P>0.05); no significant difference was found in every other two groups (P<0.05); the absolute count of CD4(+); CD25(+); Foxp3(+);/CD127(low/-); Treg decreased gradually., Conclusion: CD4(+); CD25(+); Foxp3(+);/CD127(low/-); Treg may play a role in the immunopathogenesis of persistent HIV infection.

Objective: To investigate the effect of resveratrol on the proliferation and apoptosis of synoviocytes in patients with rheumatoid arthritis (RA) in vitro and explore its mechanism., Methods: The levels of cell proliferation of synoviocytes in RA after 24 h treated with different concentrations of resveratrol were measured by monotetrazolium colourmetric assay method. The percentages of synoviocytes apoptosis in RA after 24 h treated with different concentrations of resveratrol were tested by TUNEL and flow cytometry. The relative activities of caspase-3 were determined by colorimetric assay after 4, 8, 12, 18, and 24 h treated with resveratrol (200 micromol/L) and 12 h treated with different concentrations of resveratrol. The cleavages of pro-caspase-3 were analyzed by Western blot after 24 h treated with different concentrations of resveratrol., Results: The levels of cell proliferation of synoviocytes with RA after 24 h treated with different concentrations of resveratrol were significantly decreased compared with the control group (P<0.01). The percentages of the apoptotic cells were increased of resveratrol-treated after 24 h, the apoptosis rates between the treated groups and the control group were significantly different (P<0.01). When the synoviocytes in RA were treated with 200 micromol/L resveratrol for different time respectively, the caspase-3 activity began to rise significantly at 4h, reaching the peak at 12 h, and was still much higher than that of the control group at 24 h (P<0.01). After the cells were treated with different concentrations of resveratrol for 12 h, caspase-3 activity increased in a concentration-dependent manner. After synoviocytes in RA were treated with different concentrations of resveratrol for 24 h, the expressions of pro-caspase-3 decreased as the concentration increased, the caspase-3 active fragment P11 (11 kD) appeared at 100 micromol/L and was increased at 400 micromol/L., Conclusion: Resveratrol inhibits the proliferation of synoviocytes and induces cell apoptosis in rheumatoid arthritis in vitro, which may relate to the activation of caspase-3.