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The CCD instrument background of the SMILE SXI 被引量:2
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作者 M.W.J.Hubbard O.Hetherington +6 位作者 D.J.Hall T.W.Buggey S.Parsons T.Arnold A.Holland C.Pagani S.Sembay 《Earth and Planetary Physics》 EI CSCD 2024年第1期15-24,共10页
The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation environments.The Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrou... The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation environments.The Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is high.The shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen Belts.Therefore,two radiation environments can be approximated based on the shutter door position:open and closed.The instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two environments.Due to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two extremes.The results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar maxima.This is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes. 展开更多
关键词 instrument background X-ray astronomy space radiation
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The Application of Permanent Magnet Synchronous Motor with Small Electrical Time Constant in Fiber Positioner
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作者 Shaoxiong Guo Yan Yang +3 位作者 Yanbin Yin Yihu Tang Yang Tian Chao Zhai 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期212-222,共11页
With the development of cutting-edge multi-object spectrographs,fiber positioners located in the focal plane are being scaled down in size,and miniature hollow-cup Permanent Magnet motors are now being considered as a... With the development of cutting-edge multi-object spectrographs,fiber positioners located in the focal plane are being scaled down in size,and miniature hollow-cup Permanent Magnet motors are now being considered as a suitable replacement for Faulhaber Precistep stepper motors.However,the small electrical time constant of such coreless motors poses a challenge,as the problem of severe commutation torque ripple in a fiber positioner running a position loop has been tricky.To overcome this challenge,it is advised to increase the Pulse Width Modulation(PWM)frequency as much as possible to mitigate the effects of the current fluctuation.This must be done while ensuring adequate resolution of the PWM generator.By employing a voltage open-loop field-oriented control based on a modulation frequency of 1 MHz,the drive current only costs 25 m A under a 3.3 V power supply.The sine degree of phase current is immaculate,and the repeat positioning accuracy can reach 2μm.Moreover,it is possible to further shrink the bill of devices and the layout area of the Printed Circuit Board,especially in sizesensitive applications.This device has been developed under the new generation of The Large Sky Area MultiObject Fiber Spectroscopic Telescope. 展开更多
关键词 instrumentation:adaptive optics instrumentation:spectrographs proper motions reference systems
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The Impact of Bias Row Noise to Photometric Accuracy:Case Study Based on a Scientific CMOS Detector
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作者 Li Shao Hu Zhan +4 位作者 Chao Liu Haonan Chi Qiuyan Luo Huaipu Mu Wenzhong Shi 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期228-246,共19页
We tested a new model of CMOS detector manufactured by the Gpixel Inc,for potential space astronomical application.In laboratory,we obtain some bias images under the typical application environment.In these bias image... We tested a new model of CMOS detector manufactured by the Gpixel Inc,for potential space astronomical application.In laboratory,we obtain some bias images under the typical application environment.In these bias images,clear random row noise pattern is observed.The row noise also contains some characteristic spatial frequencies.We quantitatively estimated the impact of this feature to photometric measurements,by making simulated images.We compared different bias noise types under strict parameter control.The result shows the row noise will significantly deteriorate the photometric accuracy.It effectively increases the readout noise by a factor of2-10.However,if it is properly removed,the image quality and photometric accuracy will be significantly improved. 展开更多
关键词 INSTRUMENTATION detectors-methods statistical-techniques image processing
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Ground-layer Adaptive Optics for the 2.5 m Wide-field and High-resolution Solar Telescope
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作者 Ying Yang Lan-Qiang Zhang +5 位作者 Nan-Fei Yan Jin-Sheng Yang Zhen Li Teng-Fei Song Xue-Jun Rao Chang-Hui Rao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期224-236,共13页
The 2.5 m wide-field and high-resolution solar telescope(WeHoST)is currently under developing for solar observations.WeHoST aims to achieve high-resolution observations over a super-wide field of view(FOV)of5′×5... The 2.5 m wide-field and high-resolution solar telescope(WeHoST)is currently under developing for solar observations.WeHoST aims to achieve high-resolution observations over a super-wide field of view(FOV)of5′×5′,and a desired resolution of 0.3″.To meet the scientific requirements of WeHoST,the ground-layer adaptive optics(GLAO)with a specially designed wave front sensing system is as the primary consideration.We introduce the GLAO configuration,particularly the wave front sensing scheme.Utilizing analytic method,we simulate the performance of both classical AO and GLAO systems,optimize the wave front sensing system,and evaluate GLAO performance in terms of PSF uniformity and correction improvement across whole FOV.The results indicate that,the classical AO will achieve diffraction-limited resolution;the suggested GLAO configuration will uniformly improve the seeing across the full 5′×5′FOV,reducing the FWHM across the axis FOV to less than0.3″(λ≥705 nm,r0≥11 cm),which is more than two times improvement.The specially designed wave front sensor schedule offers new potential for WeHoST’s GLAO,particularly the multi-FOV GLAO and the flexibility to select the detected area.These capabilities will significantly enhance the scientific output of the telescope. 展开更多
关键词 INSTRUMENTATION adaptive optics-instrumentation detectors-instrumentation high angular resolution-methods numerical-telescopes-Sun activity
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A Quick Calculation Method for Radiation Pattern of Submillimeter Telescope with Deformation and Displacement
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作者 Jia You Yi-Wei Yao Zheng Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期249-265,共17页
Radiation pattern captures the electromagnetic performance of reflector antennas,which is significantly affected by the deformation of the primary reflector due to gravity and the displacement of the secondary reflect... Radiation pattern captures the electromagnetic performance of reflector antennas,which is significantly affected by the deformation of the primary reflector due to gravity and the displacement of the secondary reflector.During the design process of large reflector antennas,a substantial amount of time is often dedicated to iteratively adjusting structural parameters and validating electromagnetic performance.To improve the efficiency of the design process,we first propose an approximate calculation method of optical path difference(OPD)for the deformation of the primary reflector under gravity and the displacement of the secondary reflector.Then an OPD fitting function based on the modified Zernike polynomials is proposed to capture the phase difference of radiation over the aperture plane,based on which the radiation pattern will be obtained quickly by the aperture field integration method.Numerical experiments demonstrate the effectiveness of the proposed quick calculation method for analyzing the radiation pattern of a 10.4 m submillimeter telescope antenna at its highest operating frequency of 856 GHz.In comparison with the numerical simulation method based on GRASP(which is an antenna electromagnetic analysis tool combining physical optics(PO)and physical theory of diffraction(PTD)),the quick calculation method reduces the time for radiation pattern analysis from more than one hour to less than two minutes.Furthermore,the quick calculation method exhibits excellent accuracy for the figure of merit(FOM)of the radiation pattern.Therefore,the proposed quick calculation method can obtain the radiation pattern with high speed and accuracy.Compared to the time-consuming numerical simulation method(PO and PTD),it can be employed for quick analysis of the radiation pattern for the lateral displacement of the secondary reflector and the deformation of the primary reflector under gravity in the design process of a reflector antenna. 展开更多
关键词 INSTRUMENTATION high angular resolution-methods data analysis-methods ANALYTICAL
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Development of a scintillating-fiber-based beam monitor for the coherent muon-to-electron transition experiment
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作者 Yu Xu Yun-Song Ning +7 位作者 Zhi-Zhen Qin Yao Teng Chang-Qing Feng Jian Tang Yu Chen Yoshinori Fukao Satoshi Mihara Kou Oishi 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期156-164,共9页
The coherent muon-to-electron transition(COMET)experiment is a leading experiment for the coherent conversion of μ^(-)N→e^(-)N using a high-intensity pulsed muon beamline,produced using innovative slow-extraction te... The coherent muon-to-electron transition(COMET)experiment is a leading experiment for the coherent conversion of μ^(-)N→e^(-)N using a high-intensity pulsed muon beamline,produced using innovative slow-extraction techniques.Therefore,it is critical to measure the muon beam characteristics.We set up a muon beam monitor(MBM),where scintillating fibers woven in a cross shape were coupled to silicon photomultipliers to measure the spatial profile and timing structure of the extracted muon beam for the COMET.The MBM detector was tested successfully with a proton beamline at the China Spallation Neutron Source and took data with good performance in the commissioning run.The development of the MBM,including its mechanical structure,electronic readout,and beam measurement results,are discussed. 展开更多
关键词 Beam instrumentation Profile monitor Scintillating fiber Silicon photomultipliers
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Design and Cryogenic Performance of a Hexapod Platform for a Large Ground-based Wide Field Survey Telescope
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作者 Yang Yu Xue-Wen Wang +3 位作者 Yu Zhang Jia-Lin Sun Zhen-Bang Xu Jian-Li Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期178-187,共10页
The thermal gradient is an important factor that causes degradation to the image quality of telescopes. In order to ensure the accurate alignment of the primary focus unit and the primary mirror, the hexapod platform(... The thermal gradient is an important factor that causes degradation to the image quality of telescopes. In order to ensure the accurate alignment of the primary focus unit and the primary mirror, the hexapod platform(as a corrector) is investigated in this paper. First, a ground-based telescope with 2.5 m aperture and 3.5 deg field of view is described. The telescope is under construction, and it is expected to be finished in 2023. Second, the hexapod platform with flexure hinges utilized to adjust the primary focus unit is proposed, which is applied as a corrector.Then, the inverse kinematics of the platform is established and an open-loop control system is built based on it.Finally, the cryogenic performance test for the hexapod platform is performed. The experimental results show that the resolution and repeatability of the translation for the hexapod platform can be achieved at the micrometer level.The resolution and repeatability of the rotation can be achieved at the arc-second level. Therefore, the cryogenic performance of the hexapod platform can meet the optical imaging requirements of the wide-field ground-based telescope. The kinematic analysis and cryogenic performance tests in the paper provide a technical reference for the precise alignment of the primary focus unit and the primary mirror, which can improve the imaging quality of the telescope. 展开更多
关键词 methods:miscellaneous space vehicles:instruments telescopes MISCELLANEOUS
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Disturbance Observer-based Pointing Control of Leighton Chajnantor Telescope
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作者 Weirui Chen Zheng Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期135-150,共16页
Leighton Chajnantor Telescope(LCT), i.e., the former Caltech Submillimeter Observatory telescope, will be refurbished at the new site in Chajnantor Plateau, Chile in 2023. The environment of LCT will change significan... Leighton Chajnantor Telescope(LCT), i.e., the former Caltech Submillimeter Observatory telescope, will be refurbished at the new site in Chajnantor Plateau, Chile in 2023. The environment of LCT will change significantly after its relocation, and the telescope will be exposed to large wind disturbances directly because its enclosure will be completely open during observation. The wind disturbance is expected to be a challenge for LCT's pointing control since the existing control method cannot reject this disturbance very well. Therefore, it is very necessary to develop a new pointing control method with good capability of disturbance rejection. In this research, a disturbance observer—based composite position controller(DOB-CPC) is designed, in which an H∞feedback controller is employed to compress the disturbance, and a feedforward linear quadratic regulator is employed to compensate the disturbance precisely based on the estimated disturbance signal. Moreover, a controller switching policy is adopted, which applies the proportional controller to the transient process to achieve a quick response and applies the DOB-CPC to the steady state to achieve a small position error. Numerical experiments are conducted to verify the good performance of the proposed pointing controller(i.e., DOB-CPC) for rejecting the disturbance acting on LCT. 展开更多
关键词 instrumentation:miscellaneous methods:analytical methods:numerical telescopes
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Magnetic field regression using artificial neural networks for cold atom experiments
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作者 陈子霆 黃建陶 +6 位作者 Bojeong Seo 黄明琛 Mithilesh K.Parit 何逸飞 甄浩廷 Jensen Li Gyu-Boong Jo 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期46-51,共6页
Accurately measuring magnetic fields is essential for magnetic-field sensitive experiments in areas like atomic,molecular,and optical physics,condensed matter experiments,and other areas.However,since many experiments... Accurately measuring magnetic fields is essential for magnetic-field sensitive experiments in areas like atomic,molecular,and optical physics,condensed matter experiments,and other areas.However,since many experiments are often conducted in an isolated environment that is inaccessible to experimentalists,it can be challenging to accurately determine the magnetic field at the target location.Here,we propose an efficient method for detecting magnetic fields with the assistance of an artificial neural network(NN).Instead of measuring the magnetic field directly at the desired location,we detect fields at several surrounding positions,and a trained NN can accurately predict the magnetic field at the target location.After training,we achieve a below 0.3%relative prediction error of magnetic field magnitude at the center of the vacuum chamber,and successfully apply this method to our erbium quantum gas apparatus for accurate calibration of magnetic field and long-term monitoring of environmental stray magnetic field.The demonstrated approach significantly simplifies the process of determining magnetic fields in isolated environments and can be applied to various research fields across a wide range of magnetic field magnitudes. 展开更多
关键词 ultracold gases trapped gases measurement methods and instrumentation
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Chinese version of the Perth Alexithymia Questionnaire:psychometric properties and clinical applications
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作者 Xin-Lu Cai Qingying Ye +7 位作者 Ke Ni Lin Zhu Qian Zhang Minmin Yin Zhe Zhang Wei Wei David A.Preece Bao-Ming Li 《General Psychiatry》 CSCD 2024年第2期274-283,共10页
Background The alexithymia trait is of high clinical interest.The Perth Alexithymia Questionnaire(PAQ)was recently developed to enable detailed facet-level and valence-specific assessments of alexithymia.Aims In this ... Background The alexithymia trait is of high clinical interest.The Perth Alexithymia Questionnaire(PAQ)was recently developed to enable detailed facet-level and valence-specific assessments of alexithymia.Aims In this paper,we introduce the first Chinese version of the PAQ and examine its psychometric properties and clinical applications.Methods In Study 1,the PAQ was administered to 990 Chinese participants.We examined its factor structure,internal consistency,test-retest reliability,as well as convergent,concurrent and discriminant validity.In Study 2,four groups,including a major depressive disorder(MDD)group(n=50),a matched healthy control group for MDD(n=50),a subclinical depression group(n=50)and a matched healthy control group for subclinical depression(n=50),were recruited.Group comparisons were conducted to assess the clinical relevance of the PAQ.Results In Study 1,the intended five-factor structure of the PAQ was found to fit the data well.The PAQ showed good internal consistency and test-retest reliability,as well as good convergent,concurrent and discriminant validity.In Study 2,the PAQ was able to successfully distinguish the MDD group and the subclinical depression group from their matched healthy controls.Conclusions The Chinese version of the PAQ is a valid and reliable instrument for comprehensively assessing alexithymia in the general population and adults with clinical/subclinical depression. 展开更多
关键词 CLINICAL instrument matched
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Study on the Performance of the GRANDProto300 Particle Detector Array by Simulation
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作者 Fu-Lin Dai Quan-Bu Gou +1 位作者 Xiaoyuan Huang Yi-Qing Guo 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期173-177,共5页
The Giant Radio Array for Neutrino Detection(GRAND)is a proposed large-scale observatory designed to detect cosmic rays,gamma-rays,and neutrinos with energies exceeding 100 Pe V.The GRANDProto300 experiment is propose... The Giant Radio Array for Neutrino Detection(GRAND)is a proposed large-scale observatory designed to detect cosmic rays,gamma-rays,and neutrinos with energies exceeding 100 Pe V.The GRANDProto300 experiment is proposed as the early stage of the GRAND project,consisting of a hybrid array of radio antennas and scintillator detectors.The latter,as a mature and traditional detector,is used to cross-check the nature of the candidate events selected from radio observations.In this study,we developed a simulation software called G4GRANDProto300,based on the Geant4 software package,to optimize the spacing of the scintillator detector array and to investigate its effective area.The analysis was conducted at various zenith angles under different detector spacings,including 300,500,600,700,and 900 m.Our results indicate that,for large zenith angles used to search for cosmic-ray in the GRAND project,the optimized effective area is with a detector spacing of 500 m.The G4GRANDProto300 software that we developed could be used to further optimize the layout of the particle detector array in future work. 展开更多
关键词 astroparticle physics instrumentation:detectors (ISM:)cosmic rays
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Causal roles of gut microbiota in cholangiocarcinoma etiology suggested by genetic study
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作者 Zhi-Tao Chen Chen-Chen Ding +3 位作者 Kai-Lei Chen Yang-Jun Gu Chi-Cheng Lu Qi-Yong Li 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1319-1333,共15页
BACKGROUND Cholangiocarcinoma(CCA)is a highly malignant biliary tract cancer with poor prognosis.Previous studies have implicated the gut microbiota in CCA,but evidence for causal mechanisms is lacking.AIM To investig... BACKGROUND Cholangiocarcinoma(CCA)is a highly malignant biliary tract cancer with poor prognosis.Previous studies have implicated the gut microbiota in CCA,but evidence for causal mechanisms is lacking.AIM To investigate the causal relationship between gut microbiota and CCA risk.METHODS We performed a two-sample mendelian randomization study to evaluate potential causal associations between gut microbiota and CCA risk using genome-wide association study summary statistics for 196 gut microbial taxa and CCA.Genetic variants were used as instrumental variables.Multiple sensitivity analyses assessed result robustness.RESULTS Fifteen gut microbial taxa showed significant causal associations with CCA risk.Higher genetically predicted abundance of genus Eubacteriumnodatum group,genus Ruminococcustorques group,genus Coprococcus,genus Dorea,and phylum Actinobacteria were associated with reduced risk of gallbladder cancer and extrahepatic CCA.Increased intrahepatic CCA risk was associated with higher abundance of family Veillonellaceae,genus Alistipes,order Enterobacteriales,and phylum Firmicutes.Protective effects against CCA were suggested for genus Collinsella,genus Eisenbergiella,genus Anaerostipes,genus Paraprevotella,genus Parasutterella,and phylum Verrucomicrobia.Sensitivity analyses indicated these findings were reliable without pleiotropy.CONCLUSION This pioneering study provides novel evidence that specific gut microbiota may play causal roles in CCA risk.Further experimental validation of these candidate microbes is warranted to consolidate causality and mechanisms. 展开更多
关键词 CHOLANGIOCARCINOMA Mendelian randomization Gut microbiota Instrumental variables Sensitivity analyses
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Integration of Multiple Spectral Data via a Logistic Regression Algorithm for Detection of Crop Residue Burned Areas:A Case Study of Songnen Plain,Northeast China
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作者 ZHANG Sumei ZHANG Yuan ZHAO Hongmei 《Chinese Geographical Science》 SCIE CSCD 2024年第3期548-563,共16页
The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate ... The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and aerosols.Accurate estimation of cropland burned area is both crucial and challenging,especially for the small and fragmented burned scars in China.Here we developed an automated burned area mapping algorithm that was implemented using Sentinel-2 Multi Spectral Instrument(MSI)data and its effectiveness was tested taking Songnen Plain,Northeast China as a case using satellite image of 2020.We employed a logistic regression method for integrating multiple spectral data into a synthetic indicator,and compared the results with manually interpreted burned area reference maps and the Moderate-Resolution Imaging Spectroradiometer(MODIS)MCD64A1 burned area product.The overall accuracy of the single variable logistic regression was 77.38%to 86.90%and 73.47%to 97.14%for the 52TCQ and 51TYM cases,respectively.In comparison,the accuracy of the burned area map was improved to 87.14%and 98.33%for the 52TCQ and 51TYM cases,respectively by multiple variable logistic regression of Sentind-2 images.The balance of omission error and commission error was also improved.The integration of multiple spectral data combined with a logistic regression method proves to be effective for burned area detection,offering a highly automated process with an automatic threshold determination mechanism.This method exhibits excellent extensibility and flexibility taking the image tile as the operating unit.It is suitable for burned area detection at a regional scale and can also be implemented with other satellite data. 展开更多
关键词 crop residue burning burned area Sentinel-2 Multi Spectral Instrument(MSI) logistic regression Songnen Plain China
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Exploring the Mysteries of the Universe, and Innovation Leading the Future——Astronomical Techniques and Instruments
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《Astronomical Techniques and Instruments》 CSCD 2024年第1期I0001-I0001,共1页
Dear Readers:Astronomical Techniques and Instruments is a professional English journal of open access devoted to recent develop-ments,discoveries,and theories in astronomical techniques,methods,and instruments.It will... Dear Readers:Astronomical Techniques and Instruments is a professional English journal of open access devoted to recent develop-ments,discoveries,and theories in astronomical techniques,methods,and instruments.It will serve as a platform for dis-course,learning,and information sharing for astronomic and astrophysics professionals worldwide. 展开更多
关键词 JOURNAL devoted INSTRUMENTS
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Application of prostate resectoscope in the treatment of massive rectal bleeding after transrectal prostate puncture
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作者 Hong-Mei Li Fa-Ying Yang +3 位作者 Song Tu Peng Yan Jun Qian Jia-Xi Yao 《World Journal of Clinical Cases》 SCIE 2024年第18期3438-3443,共6页
BACKGROUND Ultrasound-guided prostate biopsy is a reliable diagnostic procedure for prostate cancer diagnosis with minimal procedure-related trauma.However,complications,such as massive rectal bleeding may occur after... BACKGROUND Ultrasound-guided prostate biopsy is a reliable diagnostic procedure for prostate cancer diagnosis with minimal procedure-related trauma.However,complications,such as massive rectal bleeding may occur after the puncture.We hypothesized that using a transrectal resectoscope could help treat massive rectal bleeding after transrectal prostate punctures.AIM To identify a simple and effective treatment for massive rectal bleeding after transrectal prostate punctures.METHODS Patients requiring treatment for massive rectal bleeding after transrectal prostate punctures were included.A SIMAI resectoscope was inserted through the anus.Direct electrocoagulation was performed for superficial bleeding points.Part of the rectal mucosa or surface muscle layer was removed to expose deep bleeding points,followed by electrocoagulation.An electric cutting ring was used to compress and stop the bleeding for jet-like points before electrocoagulation.The fluid color in the drainage tube was monitored postoperatively for continuous bleeding.RESULTS Eight patients were included from 2012 to 2022.None of the patients with massive rectal bleeding after the transrectal prostate punctures improved with conventional conservative and blood transfusion treatments.Two patients had an inferior artery embolism,and digital subtraction angiography was ineffective.All patients received emergency transanal prostate resection,which immediately stopped the bleeding.Four days after the procedure,the patients had recovered and were discharged.CONCLUSION Using a transanal prostate resection instrument is a simple,safe,and effective method for treating massive rectal bleeding after transrectal prostate punctures. 展开更多
关键词 ELECTROCOAGULATION Hemostasis Transanal prostate resection instrumentation Prostate puncture
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Development and applications of the quasi‐dynamic triaxial apparatus for deep rocks
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作者 Jinzhi Luo Yanyan Cai +3 位作者 Jin Yu Jianzhi Zhang Yaoliang Zhu Yao Wei 《Deep Underground Science and Engineering》 2024年第1期70-90,共21页
The mechanical behaviors of deep rocks have always posed a challenge for the implementation and safe operation of major underground engineering projects.To this end,this study modified the existing mainstream rock mec... The mechanical behaviors of deep rocks have always posed a challenge for the implementation and safe operation of major underground engineering projects.To this end,this study modified the existing mainstream rock mechanics instruments equipped with a dynamic disturbance loading system and developed a second‐generation TFD‐2000/D triaxial instrument.The first‐generation device is equipped with an independent disturbance system and an advanced EDC‐580 all‐digital servo controller,which can apply disturbing load independently,implement the function of cyclic disturbance,and combine dynamic and static disturbances.The instrument was found to be reliable for use in analyzing the damage process of rocks in the disturbance test of marbles.The second‐generation instrument tackles three limitations of the first‐generation instrument:(i)it upgrades the strain measurement system and uses extensometers with linear variable differential transformers to accurately measure deformation;(ii)it uses the self‐balanced chamber to replace the Hoek–Franklin triaxial cell and auto‐balancing triaxial pressure chamber;and(iii)the loading rod is independently equipped with an EDC‐580 all‐digital servo controller,which measures precise loads.The experimental findings confirmed that the second‐generation instrument can be used for rock mechanics testing under cyclic disturbance loading,the disturbance–stress relaxation cycle,and the creep–fatigue cycle.In this sense,the second‐generation instrument can be a useful addition to deep rock mechanical instruments and provide a valuable reference. 展开更多
关键词 complex stress conditions deep rock disturbance loading modification of instrument rock mechanics
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Catatonia:A deep dive into its unfathomable depths
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作者 Peter Phiri Gayathri Delanerolle +4 位作者 Oliver Hope Tharangini Murugaiyan Geoffrey Dimba Shanaya Rathod Zukiswa Zingela 《World Journal of Psychiatry》 SCIE 2024年第2期210-214,共5页
This editorial addresses catatonia,a complex neuropsychiatric syndrome characterised by a spectrum of psychomotor disturbances.The editorial seeks to clarify the ambiguous aspects of catatonia,integrating recent resea... This editorial addresses catatonia,a complex neuropsychiatric syndrome characterised by a spectrum of psychomotor disturbances.The editorial seeks to clarify the ambiguous aspects of catatonia,integrating recent research findings,including global studies and diagnostic advancements.It discusses catatonia’s clinical manifestations,prevalence,and associated psychiatric and medical conditions,with particular emphasis on its frequent co-occurrence with schizophrenia and mood disorders.The prevalence of catatonia,which varies across psychiatric populations,is illustrated by a significant study conducted in Nelson Mandela Bay,South Africa.This study provides valuable insights into the effectiveness of the Bush-Francis Screening Instrument compared to the Diagnostic and Statistical Manual 5 criteria in diagnosing catatonia.The editorial evaluates treatment approaches,primarily focusing on benzodiazepines and electroconvulsive therapy,and discusses emerging therapeutic strategies.It underscores the importance of robust diagnostic frameworks and early intervention in managing catatonia,as recommended by the latest evidence-based consensus guideline.Furthermore,it suggests future research directions,particularly in exploring the neurobiological and genetic factors of catatonia,to enhance our understanding and improve treatment outcomes.This editorial succinctly aims to demystify catatonia and provide valuable insights for clinicians and researchers in mental health care. 展开更多
关键词 CATATONIA SCHIZOPHRENIA NEUROPSYCHIATRY BENZODIAZEPINES Electroconvulsive therapy Bush-Francis screening instrument Diagnosis
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The Jiao Tong University Spectroscopic Telescope Project
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作者 JUST Team Chengze Liu +28 位作者 Ying Zu Fabo Feng Zhaoyu Li Yu Yu Hua Bai Xiangqun Cui Bozhong Gu Yizhou Gu Jiaxin Han Yonghui Hou Zhongwen Hu Hangxin Ji Yipeng Jing Wei Li Zhaoxiang Qi Xianyu Tan Cairang Tian Dehua Yang Xiangyan Yuan Chao Zhai Congcong Zhang Jun Zhang Haotong Zhang Pengjie Zhang Yong Zhang Yi Zhao Xianzhong Zheng Qingfeng Zhu Xiaohu Yang 《Astronomical Techniques and Instruments》 CSCD 2024年第1期16-30,共15页
The Jiao Tong University Spectroscopic Telescope(JUST)is a 4.4-meter f/6.0 segmented-mirror telescope dedicated to spectroscopic observations.The JUST primary mirror is composed of 18 hexagonal segments,each with a di... The Jiao Tong University Spectroscopic Telescope(JUST)is a 4.4-meter f/6.0 segmented-mirror telescope dedicated to spectroscopic observations.The JUST primary mirror is composed of 18 hexagonal segments,each with a diameter of 1.1 m.JUST provides two Nasmyth platforms for placing science instruments.One Nasmyth focus fits a field of view of 10′and the other has an extended field of view of 1.2°with correction optics.A tertiary mirror is used to switch between the two Nasmyth foci.JUST will be installed at a site at Lenghu in Qinghai Province,China,and will conduct spectroscopic observations with three types of instruments to explore the dark universe,trace the dynamic universe,and search for exoplanets:(1)a multi-fiber(2000 fibers)medium-resolution spectrometer(R=4000-5000)to spectroscopically map galaxies and large-scale structure;(2)an integral field unit(IFU)array of 500 optical fibers and/or a long-slit spectrograph dedicated to fast follow-ups of transient sources for multi-messenger astronomy;(3)a high-resolution spectrometer(R~100000)designed to identify Jupiter analogs and Earth-like planets,with the capability to characterize the atmospheres of hot exoplanets. 展开更多
关键词 Astronomical instrumentation Optical telescopes Large-scale structure of the universe Redshift surveys Time domain astronomy Exoplanet astronomy
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Analysis Of Urban Planning Instruments in Comala,Colima,Mexico(1997-2009)from a Gender Perspective-A Secondary Publication
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作者 E.J.García Espíritu P.Chung Alonso +2 位作者 I.BarajasÁvalos M.S.R.Covarrubias Ruesga M.P.Ramírez Rivera 《Journal of Architectural Research and Development》 2024年第1期93-101,共9页
This work is carried out based on the analysis of urban planning instruments,taking the gender perspective as a foundation.It arises from the inclusion of women in the participation of urban development,through an ana... This work is carried out based on the analysis of urban planning instruments,taking the gender perspective as a foundation.It arises from the inclusion of women in the participation of urban development,through an analysis of the gender gaps that have marked the history of women,the inequalities serve as a basis for carrying out this study.It highlights the challenges we face today as a society in the process of building citizen participation,where we must all be recognized and have equal opportunities within the territory in which we live.This article analyzes the extent to which the Municipal Urban Development Programs of the Mexican municipality of Comala,Colima,Mexico,consider the recommendations on gender and urbanism,established since the 1990s by international entities and applied transversally to urban planning policies.Considerable differences are found between women and men in terms of empowerment and participation in urban territorial planning instruments,mainly in the oldest instrument(1997).Significant progress is observed in the most recent document and is currently in force in the municipality of Comala(2009). 展开更多
关键词 Planning instruments Gender perspective Urban planning
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Instrument Automation Control System Faults and Maintenance
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作者 Jianwei Li 《Journal of Electronic Research and Application》 2024年第1期16-21,共6页
This article explores the topic of fault diagnosis and maintenance strategies for instrument automation control systems,analyzing them through specific cases.The aim of this research is to improve the stability and re... This article explores the topic of fault diagnosis and maintenance strategies for instrument automation control systems,analyzing them through specific cases.The aim of this research is to improve the stability and reliability of the system by conducting a thorough investigation of faults and maintenance in instrument automation control systems.By doing so,this research hopes to provide a strong guarantee for the smooth progress of industrial production. 展开更多
关键词 Instrument automation Control system failure Maintenance
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