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1.
J Opt Soc Am A Opt Image Sci Vis ; 40(6): 1051-1057, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37706758

ABSTRACT

At present, the methods for measuring cloud height and thickness mainly include using micro-pulse lidar and microwave radiometer data. To further study cloud height and thickness, a superconducting nanowire single-photon detector (SNSPD) is applied to a lidar system for the first time, to the best of our knowledge, to analyze the cloud height and thickness. In the experiment, a 1.2-m-diameter horizon telescope is used for laser emitting and echo receiving, a 1064 nm near-IR pulse laser with a single pulse energy of 4 mJ is used as the system emission laser, and a 4-pixel SNSPD array detector is used as the end receiver to complete the echo photon reception. By analyzing the experimental data, the distributions of cloud height and cloud thickness can be obtained using the laser ranging system. The cloud cover condition on a certain day was measured, and the obtained cloud bottom height was about 1222 m, cloud top height was about 1394 m, and cloud cover thickness was about 172 m. The difference between the cloud cover thickness and the forecast value was 28 m. The cloud cover height and thickness measured by this method are true and credible.

2.
Appl Opt ; 60(36): 11058-11065, 2021 Dec 20.
Article in English | MEDLINE | ID: mdl-35201094

ABSTRACT

High-repetition-rate lunar laser ranging (LLR) has great prospects and significance. We have successfully obtained the effective echo signals of all five corner-cube reflectors (CCRs) on the lunar surface by using a 100 Hz repetition rate. This method can effectively improve the detection ability but has some defects: for example, the main wave and echo signals overlap. In this paper, the frequency selection and signal overlap are theoretically analyzed. The results show that the existing target prediction accuracy can meet the requirement of a 100 Hz repetition rate LLR. In the experiment, the use of a high-repetition-rate pulse laser allowed us to obtain detailed CCR information, such as the column number of CCRs, which will prove that the effective echo signals of LLR are reflected by the CCRs. Finally, we propose to use the resolved data to calculate the precision of inner coincidence and believe the accuracy can be within a millimeter.

3.
Biometals ; 29(2): 265-74, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26857738

ABSTRACT

Three experiments were conducted to investigate the effects of inorganic and organic Mn sources on MnSOD mRNA, protein and enzymatic activity and the possible signal pathways. The primary broiler myocardial cells were treated with MnCl2 (I) or one of organic chelates of Mn and amino acids with weak, moderate (M) or strong (S) chelation strength for 12 and 48 h. Cells were preincubated with superoxide radical anions scavenger N-acetylcysteine (NAC) or specific inhibitors for MAPKs and protein tyrosine kinase (PTK) or protein kinase C (PKC) for 30 min before treatments of I and M. The MnSOD mRNA, protein and enzymatic activity, phosphorylated MAPKs or protein kinases activations were examined. The results showed that additions of Mn increased (P < 0.05) MnSOD mRNA levels and M was more effective than I. Additions of Mn elevated (P < 0.05) MnSOD protein levels and enzymatic activities, and no differences were found among I and M. Addition of NAC did not decrease (P > 0.05) Mn-induced MnSOD mRNA and protein levels. None of the three MAPKs was phosphorylated (P > 0.05) by Mn. Additions of Mn decreased (P < 0.05) the PTK activities and increased (P < 0.05) the membrane PKC contents. Inhibitors for PTK or PKC decreased (P < 0.05) Mn-induced MnSOD protein levels. The results suggested that Mn-induced MnSOD mRNA and protein expressions be not related with NAC, and MAPK pathways might not involve in Mn-induced MnSOD mRNA expression. PKC and PTK mediated the Mn-induced MnSOD protein expression.


Subject(s)
Avian Proteins/metabolism , Manganese/pharmacology , Protein Kinase C/metabolism , Protein-Tyrosine Kinases/metabolism , Superoxide Dismutase/metabolism , Animals , Cells, Cultured , Chickens , Enzyme Activation , Male , Phosphorylation , Protein Biosynthesis , Protein Processing, Post-Translational
4.
Biol Trace Elem Res ; 144(1-3): 695-704, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21671088

ABSTRACT

Previous studies showed that dietary manganese can increase the MnSOD mRNA expression in a dose-dependent manner in the heart of broilers. In order to explore the specific mechanism of the MnSOD expression induced by manganese, a model of MnSOD expression was developed with primary cultured broiler myocardial cells. The objective of the present study was to investigate whether the model was working or not and to determine how manganese affects the expression of the enzyme in broiler myocardial cells in vitro. In experiment 1, various amount of manganese (0, 0.25, 0.5, 1, 2, and 4 mM) were added into the cultures for 24-h incubation to investigate MnSOD expression and for 0-, 6-, 12-, 24-, 36-, and 48-h incubation to measure the cell viability. In experiment 2, the most suitable Mn supplementation based on the results of experiment 1 was added into cultures for 6-, 12-, 24-, and 48-h incubation. The results showed that MnSOD mRNA, MnSOD protein, and MnSOD activity were induced by manganese in dose- and time-dependent manner. Manganese regulates MnSOD expression not only at transcriptional level but also at translational and/or posttranslational levels.


Subject(s)
Chickens/physiology , Gene Expression Regulation, Enzymologic/drug effects , Manganese/pharmacology , Myocytes, Cardiac/enzymology , Superoxide Dismutase/biosynthesis , Animals , Blotting, Western , Cell Count , Cell Separation , Cell Survival/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Male , Myocytes, Cardiac/drug effects , Nutritional Physiological Phenomena , Oxidative Stress/drug effects , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction
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