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1.
Appl Opt ; 63(3): 604-610, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38294370

RESUMO

In this work, a spatiotemporal metasurface is proposed to manipulate the path of photons flexibly. The spatial modulation is induced by the rectangle silicon units aligned on silica in a manner with a phase gradient only for y-polarized photons, and the temporal modulation is contributed by the pumps of constructing Kerr dynamic gratings. By quantizing designed metasurfaces, the analytical solutions of output photon states can be derived correspondingly. Reversal design could be implemented by tailoring the profile of higher harmonics to infer the intensity of pumps, size of meta-atoms, and initial state. The path-polarization entanglement and correlations of output photons are realized, and then a CNOT gate is obtained by utilizing the deflection of the photon path. This work provides a scheme to deal with the spatiotemporal metasurfaces and expands the applications of metasurfaces in the quantum realm.

2.
Front Plant Sci ; 14: 1275141, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023893

RESUMO

Introduction: Climate change and mono-afforestation or mono-reforestation have continuously caused a decline in biodiversity and ecosystem services on forest plantations. Key plant functional traits in forests or plantations may affect ecosystem functions after forest management practices. Plant clonality, a key functional trait, frequently links to biodiversity and ecosystem functions and affects the biodiversity-ecosystem functioning relationship. However, little is known about how plant clonality affects ecosystem functions and services of plantations after forest management. Methods: We conducted a field experiment to discuss the diversity and proportion of clonal plants, plant diversity of the communities, and ecosystem service functions and their relationships under 10 years of close-to-nature (CTN) management, artificial gap management, and control (i.e., without management) in the three stages of C. Lanceolata plantations. Results: Our results showed that CTN and gap management modes significantly facilitated diversity of clonal plants, plant diversity of the communities, and parameters of ecosystem service functions in C. lanceolata plantations. Moreover, CTN management promoted plant community diversity, soil water conservation, and carbon storage the most in the earlier stand stages. Diversity of clonal plants was significantly positively correlated with ecosystem service functions after forest management. Structural equation modeling analysis indicated that forest gap or CTN management indirectly positively affected ecosystem service functions through increasing diversity of clonal woody plants and plant diversity of the communities. Conclusion: Our results indicate a highly positive effect of gap or CTN management on diversity and proportion of clonal plants and on plant diversity of the communities, which link to improvements in ecosystem service functions (i.e., water and soil conservation and carbon storage). The link between forest management, diversity, and ecosystem functions suggests that key functional traits or plant functional groups should be considered to underline the mechanism of traits-ecosystem functioning relationships and the restoration of degraded plantations.

3.
Pharmaceuticals (Basel) ; 16(2)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-37259426

RESUMO

Morphine, one of the most efficacious analgesics, is effective in severe pain, especially in patients with concomitant painful cancers. The clinical use of morphine may be accompanied by increased immunosuppression, susceptibility to infection and postoperative tumor metastatic recurrence, and the specific mechanisms and clinical strategies to alleviate this suppression remain to be investigated. Expression of CD11b is closely associated with the macrophage phagocytosis of xenobiotic particles, bacteria or tumor cells. Here, we find that morphine at 0.1-10 nM levels inhibited CD11b expression and function on macrophages via a µ-opioid receptor (MOR)-dependent mechanism, thereby reducing macrophage phagocytosis of tumor cells, a process that can be reversed by thymopentin (TP5), a commonly used immune-enhancing adjuvant in clinical practice. By knocking down or overexpressing MOR on macrophages and using naloxone, an antagonist of the MOR receptor, and LA1, a molecule that promotes macrophage CD11b activation, we suggest that morphine may regulate macrophage phagocytosis by inhibiting the surface expression and function of macrophage CD11b through the membrane expression and activation of MOR. The CD47/SIRPα axis, which is engaged in macrophage-tumor immune escape, was not significantly affected by morphine. Notably, TP5, when combined with morphine, reversed the inhibition of macrophage phagocytosis by morphine through mechanisms that promote membrane expression of CD11b and modulate its downstream signaling (e.g., NOS2, IFNG, IL1B and TNFA, as well as AGR1, PDGFB, IL6, STAT3, and MYC). Thus, altered membrane expression and function of CD11b may mediate the inhibition of macrophage phagocytosis by therapeutic doses of morphine, and the reversal of this process by TP5 may provide an effective palliative option for clinical immunosuppression by morphine.

4.
Front Plant Sci ; 13: 857972, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35548285

RESUMO

Pinus elliottii × Pinus caribaea is an interspecific pine hybrid of major economic importance. Somatic embryogenesis and plant regeneration in P. elliottii × P. caribaea on solid medium have been reported previously; however, a current limitation is the lack of a stable and effective method for its commercial use. The objective of this study was to establish a suspension culture system and evaluate the effect of multiple methods synergistically on the synchronization of embryo development in P. elliottii × P. caribaea. For the former, a protocol to initiate and establish a suspension culture system of P. elliottii × P. caribaea was presented. Based on biomass growth, the growth of embryogenic calli (EC) followed an S-shape curve in suspensions grown for a 15-day period, and the exponential phase of cell suspensions was reached between days 3 and 6. The initial packed cell volume (PCV) and revolutions per minute (rpm) have a significant effect on the proliferation of EC, and the highest proliferation multiple reached 6.86 (±0.06) at the initial density of 5 ml PCV under a 9-10 days transfer interval in the dark on a rotary shaker at 70 rpm. For the latter, the influence of abscisic acid (ABA), ammonium (NH4 +), nitrate (NO3 -), low temperature, and polyethylene glycol (PEG) on somatic embryogenesis was very significant. When EC were suspended in the medium at a presence of 37.84 µM/L ABA, as many as 274 mature cotyledonary embryos/ml PCV of cells were thereafter formed in the mature medium, and 266 somatic embryos were obtained on mature medium after suspension culture in liquid medium containing 10 mmol/L NH4 + and 30 mmol/L NO3 -. Furthermore, reducing the concentration of 2,4-dichlorophenoxyacetic acid gradually and at 4°C incubation for 12 h in the initial exponential phase could promote the synchronization of somatic embryogenesis, which resulted in 260 mature cotyledonary embryos. This suspension culture system and method of synchronic control can be used in the large-scale production of P. elliottii × P. caribaea seedlings.

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