In order to improve the machining efficiency of the dish wheel grinding face gear, two changes are proposed:a disk wheel grinding face gear with a long radius and a multi-axis movement optimization method for tooth su...In order to improve the machining efficiency of the dish wheel grinding face gear, two changes are proposed:a disk wheel grinding face gear with a long radius and a multi-axis movement optimization method for tooth surface correction. Based on the grinding principle of face gears, the equation of the long radius disk wheel is deduced. Based on the structure of the machining tool, the tooth surface equations of the face gear shaped by the long radius disk wheel are established. Furthermore, an optimization model of face gear tooth surface correction is established, and the machine tool motion optimization of face gear tooth surface correction is completed;Finally, a long radius disk wheel grinding face gear test is performed. After the face gear tooth surface correction, the maximum value of the tooth surface deviation is reduced from 180 μm to 16 μm which verified the correctness of the machining method.展开更多
Saxitoxin(STX)is a marine biotoxin produced by cyanobacteria and methanobacteria,which is harmful to humans and aquatic organisms.Therefore,it is urgent to establish an efficient,sensitive and selective method for the...Saxitoxin(STX)is a marine biotoxin produced by cyanobacteria and methanobacteria,which is harmful to humans and aquatic organisms.Therefore,it is urgent to establish an efficient,sensitive and selective method for the screening of STX.In this paper,based on the HAuCl_(4)/H_(2)O_(2)reaction system,gold nanoparticles(Au NPs)decorated Fe_(3)O_(4)magnetic beads(Fe3O4@Au NPs)and Pt/Au nanozymes(Pt/Au NZs),an improved surface-enhanced Raman scattering(SERS)aptasensor was proposed for sensitive and selective detection of STX.Firstly,SERS tag(4-mercaptobenzoic acid)and aptamer modified Fe3O4@Au NPs were hybridized with complementary DNA modified Pt/Au NZs(Pt/Au-cDNA)to form the specific complexes.Wherein,aptamer acted as capture agent to specifically recognize STX,Pt/Au NZs catalyzed HAuCl_(4)/H_(2)O_(2)reaction to enhance SERS signal,and Fe_(3)O_(4)facilitated the magnetic separation and simple detection operations.The SERS aptasensor achieved sensitive detection of STX with a wide linear range from 0.02 to 0.8μmol/L and a low limit of detection(LOD)of 13 nmol/L(signal-to-noise(S/N)=3).To evaluate the performance of this method,STX were detected in the spiked seafood samples with recoveries from 78.75%to 150%with relative standard deviation below 6.52%.Besides,the SERS aptasensor behaved good stability and repeatability,revealing its promising potential in STX detection and food safety detection.展开更多
Complete rectal prolapse,characterized by the protrusion of the rectal wall layers through the anal canal,poses significant treatment challenges,particularly due to controversies surrounding surgical approaches and th...Complete rectal prolapse,characterized by the protrusion of the rectal wall layers through the anal canal,poses significant treatment challenges,particularly due to controversies surrounding surgical approaches and the absence of a standardized assessment system.This study comprehensively reviews the main surgical tech-niques for complete rectal prolapse,categorized as transabdominal and transpe-rineal/transanal procedures.Despite various techniques,challenges persist,inclu-ding high recurrence rates and potential complications.Factors influencing the choice of the surgical approach include patient characteristics,symptomatology,and surgical expertise.With advances in medical technology,laparoscopic and robotic surgeries offer promising avenues,albeit with considerations of cost and accessibility.Ultimately,treatment plans tailored to the individual needs of the patient and surgical expertise are essential.Although controversies remain,the continued refinement of surgical techniques holds promise for improving out-comes in complete rectal prolapse surgery.展开更多
基金Supported by Key Project of Advanced Research Foundation(9140A18020113)Advanced Research Foundation Project(9140A18020212)+1 种基金Advanced Research Project(51318025131812)
文摘In order to improve the machining efficiency of the dish wheel grinding face gear, two changes are proposed:a disk wheel grinding face gear with a long radius and a multi-axis movement optimization method for tooth surface correction. Based on the grinding principle of face gears, the equation of the long radius disk wheel is deduced. Based on the structure of the machining tool, the tooth surface equations of the face gear shaped by the long radius disk wheel are established. Furthermore, an optimization model of face gear tooth surface correction is established, and the machine tool motion optimization of face gear tooth surface correction is completed;Finally, a long radius disk wheel grinding face gear test is performed. After the face gear tooth surface correction, the maximum value of the tooth surface deviation is reduced from 180 μm to 16 μm which verified the correctness of the machining method.
基金supported by the National Natural Science Foundation of China(3236062242388101)+2 种基金the Specific Research Fund of the Innovation Platform for Academicians of Hainan Province(YSPTZX202152)the Open Project of Key Laboratory of Tropical Fruits and Vegetables Quality and Safety,State Administration for Market Regulation(KF-2025001)the China Postdoctoral Science Foundation(2024M760311).
文摘Saxitoxin(STX)is a marine biotoxin produced by cyanobacteria and methanobacteria,which is harmful to humans and aquatic organisms.Therefore,it is urgent to establish an efficient,sensitive and selective method for the screening of STX.In this paper,based on the HAuCl_(4)/H_(2)O_(2)reaction system,gold nanoparticles(Au NPs)decorated Fe_(3)O_(4)magnetic beads(Fe3O4@Au NPs)and Pt/Au nanozymes(Pt/Au NZs),an improved surface-enhanced Raman scattering(SERS)aptasensor was proposed for sensitive and selective detection of STX.Firstly,SERS tag(4-mercaptobenzoic acid)and aptamer modified Fe3O4@Au NPs were hybridized with complementary DNA modified Pt/Au NZs(Pt/Au-cDNA)to form the specific complexes.Wherein,aptamer acted as capture agent to specifically recognize STX,Pt/Au NZs catalyzed HAuCl_(4)/H_(2)O_(2)reaction to enhance SERS signal,and Fe_(3)O_(4)facilitated the magnetic separation and simple detection operations.The SERS aptasensor achieved sensitive detection of STX with a wide linear range from 0.02 to 0.8μmol/L and a low limit of detection(LOD)of 13 nmol/L(signal-to-noise(S/N)=3).To evaluate the performance of this method,STX were detected in the spiked seafood samples with recoveries from 78.75%to 150%with relative standard deviation below 6.52%.Besides,the SERS aptasensor behaved good stability and repeatability,revealing its promising potential in STX detection and food safety detection.
基金Supported by Science and Technology Fund Project of Guizhou Health Commission,No.gzwkj2023-042 and No.gzwkj2024-010National Natural Science Foundation of China,No.82060440+2 种基金Guizhou Provincial Science and Technology Projects,No.QKHJC ZK[2024]-210Cultivation Program for General Projects of the National Natural Science Foundation of China,No.gyfynsfc[2023]-01Cultivation Program for Regional Projects of the National Natural Science Foundation of China,No.gyfynsfc[2024]-19.
文摘Complete rectal prolapse,characterized by the protrusion of the rectal wall layers through the anal canal,poses significant treatment challenges,particularly due to controversies surrounding surgical approaches and the absence of a standardized assessment system.This study comprehensively reviews the main surgical tech-niques for complete rectal prolapse,categorized as transabdominal and transpe-rineal/transanal procedures.Despite various techniques,challenges persist,inclu-ding high recurrence rates and potential complications.Factors influencing the choice of the surgical approach include patient characteristics,symptomatology,and surgical expertise.With advances in medical technology,laparoscopic and robotic surgeries offer promising avenues,albeit with considerations of cost and accessibility.Ultimately,treatment plans tailored to the individual needs of the patient and surgical expertise are essential.Although controversies remain,the continued refinement of surgical techniques holds promise for improving out-comes in complete rectal prolapse surgery.
