Analysis of the Interference Signal of the Distributed Optical Fiber Sensing Based on DSP

In this paper, the author analyzes characteristics and extracting method of interference signal of the distributed optical fiber sensing. In the distributed optical fiber sensing, realizing alarm and positioning function only through the cross-correlation operation will increase the load of the system, can make misinformation rate of the system be improved greatly. Therefore, before the localization algorithm, adding a interference signal feature recognition is very necessary, can reduce unnecessary operation loss and reduce the load of the system, also reducing the number of the false positives.

Hyperoside promotes pollen tube growth by regulating the depolymerization effect of actin depolymerizing factor 1 on microfilaments in okra

Mature pollen germinates rapidly on the stigma,extending its pollen tube to deliver sperm cells to the ovule for fertilization.The success of this process is an important factor that limits output.The flavonoid content increased signi ficantly during pollen germination and pollen tube growth,which suggests it may play an important role in these processes.However,the speci fi c mechanism of this involvement has been little researched.Our previous research found that hyperoside can prolong the flowering period of Abelmoschus esculentus(okra),but its speci fic mechanism is still unclear.Therefore,in this study,we focused on the effect of hyperoside in regulating the actin-depolymerizing factor(ADF),which further affects the germination and growth of pollen.We found that hyperoside can prolong the effective pollination period of okra by 2-3-fold and promote the growth of pollen tubes in the style.Then,we used Nicotiana benthamiana cells as a research system and found that hyperoside accelerates the depolymerization of intercellular micro fi laments.Hyperoside can promote pollen germination and pollen tube elongation in vitro.Moreover,AeADFl was identi fied out of all AeADF genes as being highly expressed in pollen tubes in response to hyperoside.In addition,hyperoside promoted AeADF1-mediated micro filament dissipation according to micro filament severing experiments in vitro.In the pollen tube,the gene expression of AeADFl was reduced to 1/5 by oligonucleotide transfection.The decrease in the expression level of AeADFl partially reduced the promoting effect of hyperoside on pollen germination and pollen tube growth.This research provides new research directions for flavonoids in reproductive development.

Based on Fluent Numerical Calculation of Refractive Index on Rocket Engine Nozzle Plume

Numerical 2D simulation and research on internal flow field and external flow field of rocket motor nozzle using FLUENT software. Analyze the flow condition of internal flow field and external flow field, and according to add in the amount of the different gas components, obtain the clear distribution of contour of density flow field, pressure flow field and various material components and so on. Simulation results agree with the results observed from the test on the ground, and provide reference for solid rocket motor development.

ACAT1 deficiency in myeloid cells promotes glioblastoma progression by enhancing the accumulation of myeloid-derived suppressor cells

Glioblastoma(GBM)is a highly aggressive and lethal brain tumor with an immunosuppressive tumor microenvironment(TME).In this environment,myeloid cells,such as myeloid-derived suppressor cells(MDSCs),play a pivotal role in suppressing antitumor immunity.Lipometabolism is closely related to the function of myeloid cells.Here,our study reports that acetyl-CoA acetyltransferase 1(ACAT1),the key enzyme of fatty acid oxidation(FAO)and ketogenesis,is significantly downregulated in the MDSCs infiltrated in GBM patients.To investigate the effects of ACAT1 on myeloid cells,we generated mice with myeloid-specific(LyzM-cre)depletion of ACAT1.The results show that these mice exhibited a remarkable accumulation of MDSCs and increased tumor progression both ectopically and orthotopically.The mechanism behind this effect is elevated secretion of C-X-C motif ligand 1(CXCLI)of macrophages(Mo).Overall,our findings demonstrate that ACAT1 could serve as a promising drug target for GBM by regulating the function of MDSCs in the TME.

Numerical analysis and experimental research on detection of welding defects in pipelines based on magnetic flux leakage

Regular inspection of long-distance oil and gas pipelines plays an important role in ensuring the safe transportation of oil and gas,and inspection on welding defects is an important part of the inspection process.Magnetic flux leakage(MFL)is an electromagnetic non-destructive testing technique which has been commonly utilized to detect welding defects in pipelines.In the present study,Maxwell electro-magnetic simulation software was used to carry out numerical study on the welding defects in pipelines,including incomplete penetration and undercut.TheФ406 pipeline with a wall thickness of 7 mm was selected as the study case to establish the numerical model.Setting the life-off value at 1 mm,the distribution of magnetic leakage field was investigated for pipeline without defect,pipeline with incomplete penetration defect and pipeline with undercut defect respectively,the characteristic values describing the depth and width of defects were found.Furthermore,quantified equations which can be used to describe the defect depth were proposed.Finally,experimental research was carried out to validate the effectiveness of the numerical model,and the experimental results showed good consistence with the numerical calculation results.The research results indicate that,it is technically feasible and reliable to diagnose the incomplete penetration and undercut welding defects in pipelines using MFL.

纳秒激光调控CFRP复合材料表面润湿性及其对胶接性能的影响

采用纳秒激光对碳纤维增强树脂基(CFRP)复合材料进行表面预处理,调控其表面成分、粗糙度和表面润湿性,然后采用SEM、接触角测量仪、光学轮廓仪、XPS等表征CFRP复合材料的表面微观形貌、接触角、粗糙度和化学成分,并通过拉伸剪切实验评价和分析激光表面处理对CFRP复合材料胶接强度的影响规律和机制。结果表明:优化激光表面处理参数,可以去除CFRP复合材料表面的环氧树脂胶,调控其表面成分、粗糙度和表面润湿性;与未处理的CFRP复合材料相比,激光表面处理后的CFRP复合材料表面化学成分改变,表面粗糙度有所增加,润湿性提高,胶接强度也增大;与未处理CFRP复合材料相比,激光离焦量分别为5 mm、10 mm和15 mm时,处理后的CFRP复合材料胶接强度分别提高了129.41%、112.13%和105.88%;激光表面处理CFRP复合材料的表面润湿性和表面粗糙度均高于机械处理CFRP复合材料,但激光处理导致的热损伤对胶接强度提高有负面影响。

YPD-30, a prodrug of YPD-29B, is an oral small-molecule inhibitor targeting PD-L1 for the treatment of human cancer

PD-1 and PD-L1 antibodies have brought about extraordinary clinical benefits for cancer patients,and their indications are expanding incessantly.Currently,most PD-1/PD-L1 agents are administered intravenously,which may be uncomfortable for some cancer patients.Herein,we develop a novel oral-delivered small molecular,YPD-29B,which specifically targets human PD-L1.Our data suggested that YPD-29B could potently and selectively block the interaction between PD-L1 and PD-1,but did not inhibit any other immune checkpoints.Mechanistically,YPD-29B induced human PD-L1 dimerization and internalization,which subsequently activated T lymphocytes and therefore overcomes immunity tolerance in vitro.YDP-29B was modified as the YPD-30 prodrug to improve druggability.Using humanized mice with human PD-1 xenografts of human PD-L1 knock-in mouse MC38 cancer cells,we demonstrated that YPD-30 exhibited significant antitumor activity and was well tolerated in vivo.Taken together,our results indicate that YPD-30 serves as a promising therapeutic candidate for anti-human PD-L1 cancer immunotherapy.

The relationship between the contents of 13 amino acids in brain tissues and the progression of NAFLD via C57BL/6 model mice

Non-alcoholic fatty liver disease(NAFLD)is the steatosis of liver parenchyma unrelated to alcoholism,autoimmunity,and viral infection.It is also a metabolism-related syndrome,which has an unseparated relationship with adipose tissue dysfunction and obesity.Hepatic encephalopathy(HE)is one of the severe complications of chronic liver disease and one of the end-stage syndromes of liver disease.Some researchers have suggested that NAFLD,like other forms of liver injury,may be related to the metabolic disorder of branched-chain amino acids(BCAAs),which have been approved to be associated with HE influencing ammonia and energy metabolism.However,several studies have revealed the relationship among amino acids in serum,HE,and chronic liver disease;there are few studies on the contents of amino acids in brain tissues of an animal model with NAFLD.In the present research,we established a NAFLD mouse model with C57 BL/6 mice and determined the contents of 13 amino acids in brain tissues of model mice by HPLC-FLD derivatization method using ortho-phthalaldehyde(OPA)to explore the relationship between the contents of amino acids in brain tissues and the progression of NAFLD.Moreover,the study showed that the changes of amino acid contents in the brain of the C57 BL/6 mice were associated with the advancement of NAFLD,and this change might be related to the mechanism of HE.

Synergistic effects of plant hormones on spontaneous late-ripening mutant of'Jinghong'peach detected by transcriptome analysis

Objectives:Peach(Prunus persica L.)is an ancient fruit tree that originated from China.It is the climacteric fruit belonging to genus Prunus in family Rosaceae.Ethylene,which is produced during ripening,accelerates fruit softening,and therefore peaches cannot be stored for a long time.Materials and Methods:To study the mechanism of fruit late ripening,transcriptome analysis of the fruit of a late-ripening mutant of'Jinghong'peach was performed to identify genes and pathways involved in fruit late ripening.Results:A total of 1805,1511,and 2309 genes were found to be differentially expressed in W2_vs_M1,W3_vs_M2,and W3_vs_M3,respectively.Functional enrichment analysis of the differentially expressed genes showed they were related to carotenoid biosynthesis,starch and sucrose metabolism plant hormone signal transduction,flavonoid biosynthesis,and photosynthesis.The expression trends of ripening-related genes that encode transcription factors and plant hormone signal transduction-related genes that encode enzymes were similar.Conclusions:It will help to elucidate the transcriptional regulatory network of fruit development in the spontaneous late-ripening mutant of‘Jinghong’peach and provide a theoretical basis for understanding the molecular regulatory mechanism of fruit ripening.

Characteristics of flow and heat transfer of shell-and-tube heat exchangers with overlapped helical baffles

The characteristics of flow and heat transfer of shell-and-tube heat exchangers with overlapped helical baffles (STHXsHB) were illustrated through a theoretical analysis and numerical simulation. The ideal helical flow model was constructed to demonstrate parts of the flow characteristics of the STHXsHB, providing theoretical evidence of short-circuit and back flows in a triangular zone. The numerical simulation was adopted to describe the characteristics of helical, leakage, and bypass streams. In a fully developed section, the distribution of velocity and wall heat transfer coefficient has a similar trend, which presents the effect of leakage and bypass streams. The short-circuit flow accelerates the axial velocity of the flow through the triangular zone. Moreover, the back flow enhances the local heat transfer and causes the ascent of flow resistance. This study shows the detailed features of helical flow in STHXsHB, which can inspire a reasonable optimization on the shell-side structure.