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1.
Phys Rev Lett ; 126(2): 020503, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33512193

RESUMO

Entanglement distribution has been accomplished using a flying drone, and this mobile platform can be generalized for multiple mobile nodes with optical relay among them. Here we develop the first optical relay to reshape the wave front of photons for their low diffraction loss in free-space transmission. Using two drones, where one distributes the entangled photons and the other serves as relay node, we achieve entanglement distribution with Clauser-Horne-Shimony-Holt S parameter of 2.59±0.11 at 1 km distance. Key components for entangled source, tracking, and relay are developed with high performance and are lightweight, constructing a scalable airborne system for multinode connectio and toward mobile quantum networks.

2.
Natl Sci Rev ; 7(5): 921-928, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-34691535

RESUMO

Satellites have shown free-space quantum-communication ability; however, they are orbit-limited from full-time all-location coverage. Meanwhile, practical quantum networks require satellite constellations, which are complicated and expensive, whereas the airborne mobile quantum communication may be a practical alternative to offering full-time all-location multi-weather coverage in a cost-effective way. Here, we demonstrate the first mobile entanglement distribution based on drones, realizing multi-weather operation including daytime and rainy nights, with a Clauser-Horne-Shimony-Holt S-parameter measured to be 2.41 ± 0.14 and 2.49 ± 0.06, respectively. Such a system shows unparalleled mobility, flexibility and reconfigurability compared to the existing satellite and fiber-based quantum communication, and reveals its potential to establish a multinode quantum network, with a scalable design using symmetrical lens diameter and single-mode-fiber coupling. All key technologies have been developed to pack quantum nodes into lightweight mobile platforms for local-area coverage, and arouse further technical improvements to establish wide-area quantum networks with high-altitude mobile communication.

3.
J Biosci Bioeng ; 105(4): 335-40, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18499048

RESUMO

In order to increase the yield of S-adenosylmethionine (SAM) in recombinant Pichia pastoris, a strategy of adding oxygen vectors and supplemental carbon sources was described. Three organic solutions were used as oxygen vectors for SAM accumulation at different concentrations and addition times. Firstly, n-hexane (0.5%) or n-heptane (1.0%) was added after 72 h of cultivation to improve SAM production. Carbon metabolism was scarce during the induction phase because of low methanol concentration. Secondly, sorbitol (1.2%), selected from three candidates (glycerol, lactic acid, and sorbitol), was used as the supplemental carbon source. The yield of SAM was improved significantly (53.26%) at 1.0%n-heptane added at 72 h (48 h induction), 1.2% sorbitol added at 72, 96, and 120 h of cultivation and 1.0% methanol added every 24 h during cultivation.


Assuntos
Metionina Adenosiltransferase/biossíntese , Pichia/crescimento & desenvolvimento , Proteínas Recombinantes/biossíntese , S-Adenosilmetionina/metabolismo , Proteínas de Saccharomyces cerevisiae/biossíntese , Saccharomyces cerevisiae/enzimologia , Sorbitol/química , Meios de Cultura/química , Expressão Gênica , Metionina Adenosiltransferase/genética , Pichia/enzimologia , Pichia/genética , Proteínas Recombinantes/genética , S-Adenosilmetionina/genética , S-Adenosilmetionina/isolamento & purificação , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Tempo
4.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 28(11): 981-5, 2008 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19213338

RESUMO

OBJECTIVE: To investigate the regulatory effect of ligustrazine and Radix Astragalus (Chinese drugs for supplementing qi and activating blood circulation) on uterine mucosa stromal cyto-chemotactic factor RANTES and receptor CCR5 expression. METHODS: The eutopic and ectopic endometrial stromal cells (EMSC) isolated and purified from 10 patients with ovarian endometrial cyst were selected as the experimental group, while those from 10 patients with benign lesion were selected as the control group. After they were intervened by different factors, including astragalus injection (AI), ligustrazine injection (LI), AI + LI, and Danazol, the expression levels of RANTES and CCR5 in the cells were detected by ELISA and RT-PCR. RESULTS: RANTES expressions in eutopic and ectopic EMSC were different insignificantly (P > 0.05). The ectopic EMSC RANTES expression was 13.602 +/- 3.358 ng/L and eutopic EMSC RANTES was 12.850 +/- 7.997 ng/L in the positive control group, which was significantly higher than that in the negative control group (both being 0.027 +/- 0.016 ng/L, P <0.05), and the ectopic EMSC expressions after intervened with Chinese drugs were significantly lower than that in the positive control group (P <0.05). CCR5 expression in ectopic EMSC was 0.759 +/- 0.039 ng/L, which was higher than that in eutopic EMSC (0.249 +/- 0.026 ng/L, P <0.05). Ectopic EMSC CCR5 expression was higher in the positive control group than that in the negative control group (0.759 +/- 0.039 ng/L vs 0.478 +/- 0.094 ng/L, P <0.05). Similar situation also was shown between the positive and negative control groups in terms of eutopic EMSC CCR5 expression (0.249 +/- 0.026 ng/L vs 0.131 +/- 0.021 ng/L, P < 0.01), and the expression was significantly lower in all the Chinese drugs treated EMSC groups as compared with that in the positive control group (P < 0.01). CONCLUSION: CCR5 expression was higher in ectopic EMSC than that in eutopic EMSC. Ligustrazine and Radix Astragalus could down-regulate the auto-secretion of RANTES and CCR5 in patients with endometriosis.


Assuntos
Astrágalo/química , Quimiocina CCL5/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Endometriose/metabolismo , Receptores CCR5/metabolismo , Adulto , Células Cultivadas , Quimiocina CCL5/genética , Regulação para Baixo/efeitos dos fármacos , Endometriose/tratamento farmacológico , Endometriose/genética , Endometriose/patologia , Endométrio/citologia , Endométrio/metabolismo , Endométrio/patologia , Feminino , Humanos , Pirazinas/farmacologia , Receptores CCR5/genética , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo
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