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Selective internal radiation therapy segmentectomy:A new minimally invasive curative option for primary liver malignancies? 被引量:2
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作者 Riccardo Inchingolo Francesco Cortese +5 位作者 Antonio Rosario Pisani Fabrizio Acquafredda Roberto Calbi Riccardo Memeo Fotis Anagnostopoulos Stavros Spiliopoulos 《World Journal of Gastroenterology》 SCIE CAS 2024年第18期2379-2386,共8页
Transarterial radioembolization or selective internal radiation therapy(SIRT)has emerged as a minimally invasive approach for the treatment of tumors.This percutaneous technique involves the local,intra-arterial deliv... Transarterial radioembolization or selective internal radiation therapy(SIRT)has emerged as a minimally invasive approach for the treatment of tumors.This percutaneous technique involves the local,intra-arterial delivery of radioactive microspheres directly into the tumor.Historically employed as a palliative measure for liver malignancies,SIRT has gained traction over the past decade as a potential curative option,mirroring the increasing role of radiation segmentectomy.The latest update of the BCLC hepatocellular carcinoma guidelines recognizes SIRT as an effective treatment modality comparable to other local ablative methods,particularly well-suited for patients where surgical resection or ablation is not feasible.Radiation segmentectomy is a more selective approach,aiming to deliver high-dose radiation to one to three specific hepatic segments,while minimizing damage to surrounding healthy tissue.Future research efforts in radiation segmentectomy should prioritize optimizing radiation dosimetry and refining the technique for super-selective administration of radiospheres within the designated hepatic segments. 展开更多
关键词 Transarterial radioembolization Selective internal radiation therapy radiation segmentectomy Hepatocellular carcinoma Primary liver malignancies Personalised dosimetry
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Efficacy and safety of percutaneous transhepatic biliary radiofrequency ablation in patients with malignant obstructive jaundice 被引量:1
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作者 Ying Xing Zheng-Rong Liu +1 位作者 You-Guo Li Hong-Yi Zhang 《World Journal of Clinical Cases》 SCIE 2024年第17期2983-2988,共6页
BACKGROUND Percutaneous transhepatic cholangiodrainage(PTCD)and endoscopic retrograde cholangiopancreatography/endoscopic nasobiliary drainage are the most common clinical procedures for jaundice control in patients w... BACKGROUND Percutaneous transhepatic cholangiodrainage(PTCD)and endoscopic retrograde cholangiopancreatography/endoscopic nasobiliary drainage are the most common clinical procedures for jaundice control in patients with unresectable malignant obstructive jaundice,yet the safety and effect of endobiliary radiofrequency ablation(EB-RFA)combined PTCD is rarely reported,in this article,we report our experience of EB-RFA combined PTCD in such patients.AIM To retrospectively study the efficacy and safety of EB-RFA combined PTCD in patients with unresectable malignant obstructive jaundice.METHODS Patients with unresectable malignant obstructive jaundice treated with EB-RFA under PTCD were selected,the bile ducts of the right posterior lobe was selected as the target bile ducts in all cases.The general conditions of all patients,preoperative tumour markers,total bilirubin(TBIL),direct bilirubin(DBIL),albumin(ALB),alkaline phosphatase(ALP),and glutamyl transferase(GGT)before and on the 7th day after the procedure,as well as perioperative complications,stent patency time and patient survival were recorded.RESULTS All patients successfully completed the operation,TBIL and DBIL decreased significantly in all patients at the 7th postoperative day(P=0.009 and 0.006,respectively);the values of ALB,ALP and GGT also decreased compared with the preoperative period,but the difference was not statistically significant.Perioperative biliary bleeding occurred in 2 patients,which was improved after transfusion of blood and other conservative treatments,pancreatitis appeared in 1 patient after the operation,no serious complication and death happened after operation.Except for 3 patients with loss of visits,the stent patency rate of the remaining 14 patients was 100%71%and 29%at the 1^(st),3^(rd),and 6^(th)postoperative months respectively,with a median survival of 4 months.CONCLUSION EB-RFA under PTCD in patients with unresectable malignant obstructive jaundice has a satisfactory therapeutic effect and high safety,which is worthy of further clinical practice. 展开更多
关键词 Biliary tract tumour Malignant obstructive jaundice Percutaneous transhepatic cholangiodrainage Endoluminal radiofrequency ablation Biliary radiofrequency ablation
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Failure mechanism and infrared radiation characteristic of hard siltstone induced by stratification effect 被引量:1
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作者 CHENG Yun SONG Zhanping +2 位作者 XU Zhiwei YANG Tengtian TIAN Xiaoxu 《Journal of Mountain Science》 SCIE CSCD 2024年第3期1058-1074,共17页
The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and tempora... The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and temporal damage mechanism of hard siltstone. The uniaxial compression tests, coupled with acoustic emission(AE) and infrared radiation temperature(IRT) were conducted on siltstones with different stratification effects. The results revealed that the stratigraphic structure significantly affects the stress-strain response and strength degradation characteristics. The mechanical parameters exhibit anisotropy characteristics, and the stratification effect exhibits a negative correlation with the cracking stress and peak stress. The failure modes caused by the stratification effect show remarkable anisotropic features, including splitting failure(Ⅰ: 0°-22.50°, Ⅱ: 90°), composite failure(45°), and shearing failure(67.50°). The AE temporal sequences demonstrate a stepwise response characteristic to the loading stress level. The AE intensity indicates that the stress sensitivity of shearing failure and composite failure is generally greater than that of splitting failure. The IRT field has spatiotemporal migration and progressive dissimilation with stress loading and its dissimilation degree increases under higher stress levels. The stronger the stratification effect, the greater the dissimilation degree of the IRT field. The abnormal characteristic points of average infrared radiation temperature(AIRT) variance at local stress drop and peak stress can be used as early and late precursors to identify fracture instability. Theoretical analysis shows that the competitive relationship between compaction strengthening and fracturing damage intensifies the dissimilation of the infrared thermal field for an increasing stress level. The present study provides a theoretical reference for disaster warnings in hard sedimentary rock mass. 展开更多
关键词 Hard siltstone Failure mechanism Stratification effect Infrared radiation characteristic Temporal-damage mechanism DISSIMILATION
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Simulation of the Ecosystem Productivity Responses to Aerosol Diffuse Radiation Fertilization Effects over the Pan-Arctic during 2001–19 被引量:1
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作者 Zhiding ZHANG Xu YUE +3 位作者 Hao ZHOU Jun ZHU Yadong LEI Chenguang TIAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期84-96,共13页
The pan-Arctic is confronted with air pollution transported from lower latitudes.Observations have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).Whil... The pan-Arctic is confronted with air pollution transported from lower latitudes.Observations have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).While such DRFEs have been explored at low to middle latitudes,the aerosol impacts on pan-Arctic ecosystems and the contributions by anthropogenic and natural emission sources remain less quantified.Here,we perform regional simulations at 0.2o×0.2ousing a well-validated vegetation model(Yale Interactive terrestrial Biosphere,YIBs)in combination with multi-source of observations to quantify the impacts of aerosol DRFEs on the net primary productivity(NPP)in the pan-Arctic during 2001-19.Results show that aerosol DRFEs increase pan-Arctic NPP by 2.19 Pg C(12.8%)yr^(-1)under clear-sky conditions,in which natural and anthropogenic sources contribute to 8.9% and 3.9%,respectively.Under all-sky conditions,such DRFEs are largely dampened by cloud to only 0.26 Pg C(1.24%)yr^(-1),with contributions of 0.65% by natural and 0.59% by anthropogenic species.Natural aerosols cause a positive NPP trend of 0.022% yr^(-1)following the increased fire activities in the pan-Arctic.In contrast,anthropogenic aerosols induce a negative trend of-0.01% yr^(-1)due to reduced emissions from the middle latitudes.Such trends in aerosol DRFEs show a turning point in the year of 2007 with more positive NPP trends by natural aerosols but negative NPP trends by anthropogenic aerosols thereafter.Though affected by modeling uncertainties,this study suggests a likely increasing impact of aerosols on terrestrial ecosystems in the pan-Arctic under global warming. 展开更多
关键词 diffuse radiation fertilization effects anthropogenic aerosols natural aerosols pan-Arctic net primary productivity
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Nomogram predicting the prognosis of primary liver cancer after radiofrequency ablation combined with transcatheter arterial chemoembolization 被引量:1
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作者 Hai-Hua Shen Yu-Rong Hong +4 位作者 Wen Xu Lei Chen Jun-Min Chen Zhi-Gen Yang Cai-Hong Chen 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2630-2639,共10页
BACKGROUND The incidence and mortality rates of primary hepatocellular carcinoma(HCC)are high,and the conventional treatment is radiofrequency ablation(RFA)with transcatheter arterial chemoembolization(TACE);however,t... BACKGROUND The incidence and mortality rates of primary hepatocellular carcinoma(HCC)are high,and the conventional treatment is radiofrequency ablation(RFA)with transcatheter arterial chemoembolization(TACE);however,the 3-year survival rate is still low.Further,there are no visual methods to effectively predict their prognosis.AIM To explore the factors influencing the prognosis of HCC after RFA and TACE and develop a nomogram prediction model.METHODS Clinical and follow-up information of 150 patients with HCC treated using RFA and TACE in the Hangzhou Linping Hospital of Traditional Chinese Medicine from May 2020 to December 2022 was retrospectively collected and recorded.We examined their prognostic factors using multivariate logistic regression and created a nomogram prognosis prediction model using the R software(version 4.1.2).Internal verification was performed using the bootstrapping technique.The prognostic efficacy of the nomogram prediction model was evaluated using the concordance index(CI),calibration curve,and receiver operating characteristic RESULTS Of the 150 patients treated with RFA and TACE,92(61.33%)developed recurrence and metastasis.Logistic regression analysis identified six variables,and a predictive model was created.The internal validation results of the model showed a CI of 0.882.The correction curve trend of the prognosis prediction model was always near the diagonal,and the mean absolute error before and after internal validation was 0.021.The area under the curve of the prediction model after internal verification was 0.882[95%confidence interval(95%CI):0.820-0.945],with a specificity of 0.828 and sensitivity of 0.656.According to the Hosmer-Lemeshow test,χ^(2)=3.552 and P=0.895.The predictive model demonstrated a satisfactory calibration,and the decision curve analysis demonstrated its clinical applicability.CONCLUSION The prognosis of patients with HCC after RFA and TACE is affected by several factors.The developed prediction model based on the influencing parameters shows a good prognosis predictive efficacy. 展开更多
关键词 NOMOGRAM Primary liver cancer Radiofrequency ablation Transcatheter arterial chemoembolization PROGNOSIS Influencing factors Decision curve analysis
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Radiofrequency ablation combined with transcatheter arterial chemoembolization for recurrent liver cancer 被引量:1
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作者 Jin-You Guo Li-Li Zhao +2 位作者 Hui-Jun Cai Hui Zeng Wei-Dong Mei 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1756-1764,共9页
BACKGROUND The recurrence rate of liver cancer after surgery is high.Radiofrequency ablation(RFA)combined with transcatheter arterial chemoembolization(TACE)is an effective treatment for liver cancer;however,its effic... BACKGROUND The recurrence rate of liver cancer after surgery is high.Radiofrequency ablation(RFA)combined with transcatheter arterial chemoembolization(TACE)is an effective treatment for liver cancer;however,its efficacy in recurrent liver cancer remains unclear.AIM To investigate the clinical effect of TACE combined with RFA in the treatment of recurrent liver cancer.METHODS Ninety patients with recurrent liver cancer were divided into 2 groups according to treatment plan:Control(RFA alone);and experimental[TACE combined with RFA(TACE+RFA)].The incidence of increased alanine aminotransferase levels,complications,and other indices were compared between the two groups before and after the procedures.RESULTS One month after the procedures,the short-term efficacy rate and Karnofsky Performance Status scores of the experimental group were significantly higher than those of the control group(P<0.05).Alpha-fetoprotein(AFP)and total bilirubin levels were lower than those in the control group(P<0.05);The overall response rate was 82.22%and 66.67%in the experimental and control groups,respectively;The disease control rate was 93.33%and 82.22%in the experimental and control groups,respectively,the differences are statistically significant(P<0.05).And there were no statistical differences in complications between the two groups(P>0.05).CONCLUSION TACE+RFA was effective for the treatment of recurrent liver cancer and significantly reduced AFP levels and improved various indices of liver function. 展开更多
关键词 Transcatheter arterial chemoembolization Radiofrequency ablation Recurrent liver cancer Clinical efficacy Overall response rate Disease control rate
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High-speed performance self-powered short wave ultraviolet radiation detectors based onκ(ε)-Ga_(2)O_(3) 被引量:1
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作者 Aleksei Almaev Alexander Tsymbalov +5 位作者 Bogdan Kushnarev Vladimir Nikolaev Alexei Pechnikov Mikhail Scheglov Andrei Chikiryaka Petr Korusenko 《Journal of Semiconductors》 EI CAS CSCD 2024年第4期56-62,共7页
High-speed solar-blind short wavelength ultraviolet radiation detectors based onκ(ε)-Ga_(2)O_(3)layers with Pt contacts were demonstrated and their properties were studied in detail.Theκ(ε)-Ga_(2)O_(3)layers were ... High-speed solar-blind short wavelength ultraviolet radiation detectors based onκ(ε)-Ga_(2)O_(3)layers with Pt contacts were demonstrated and their properties were studied in detail.Theκ(ε)-Ga_(2)O_(3)layers were deposited by the halide vapor phase epitaxy on patterned GaN templates with sapphire substrates.The spectral dependencies of the photoelectric properties of struc-tures were analyzed in the wavelength interval 200-370 nm.The maximum photo to dark current ratio,responsivity,detectiv-ity and external quantum efficiency of structures were determined as:180.86 arb.un.,3.57 A/W,1.78×10^(12) Hz^(0.5)∙cm·W^(-1) and 2193.6%,respectively,at a wavelength of 200 nm and an applied voltage of 1 V.The enhancement of the photoresponse was caused by the decrease in the Schottky barrier at the Pt/κ(ε)-Ga_(2)O_(3)interface under ultraviolet exposure.The detectors demon-strated could functionalize in self-powered mode due to built-in electric field at the Pt/κ(ε)-Ga_(2)O_(3)interface.The responsivity and external quantum efficiency of the structures at a wavelength of 254 nm and zero applied voltage were 0.9 mA/W and 0.46%,respectively.The rise and decay times in self-powered mode did not exceed 100 ms. 展开更多
关键词 κ(ε)-gallium oxide solar-blind shortwave ultraviolet radiation detectors self-powered operation mode
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Unraveling the efficacy network: A network meta-analysis of adjuvant external beam radiation therapy methods after hepatectomy 被引量:1
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作者 Gao-Yuan Yang Zhi-Wei He +7 位作者 Yong-Chang Tang Feng Yuan Ming-Bo Cao Yu-Peng Ren Yu-Xuan Li Xiao-Rui Su Zhi-Cheng Yao Mei-Hai Deng 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期205-214,共10页
BACKGROUND Primary liver cancer is a malignant tumor with a high recurrence rate that significantly affects patient prognosis.Postoperative adjuvant external radiation therapy(RT)has been shown to effectively prevent ... BACKGROUND Primary liver cancer is a malignant tumor with a high recurrence rate that significantly affects patient prognosis.Postoperative adjuvant external radiation therapy(RT)has been shown to effectively prevent recurrence after liver cancer resection.However,there are multiple RT techniques available,and the differ-ential effects of these techniques in preventing postoperative liver cancer re-currence require further investigation.AIM To assess the advantages and disadvantages of various adjuvant external RT methods after liver resection based on overall survival(OS)and disease-free survival(DFS)and to determine the optimal strategy.METHODS This study involved network meta-analyses and followed the PRISMA guidelines.The data of qualified studies published before July 10,2023,were collected from PubMed,Embase,the Web of Science,and the Cochrane Library.We included relevant studies on postoperative external beam RT after liver resection that had OS and DFS as the primary endpoints.The magnitudes of the effects were determined using risk ratios with 95%confidential intervals.The results were analyzed using R software and STATA software.RESULTS A total of 12 studies,including 1265 patients with hepatocellular carcinoma(HCC)after liver resection,were included in this study.There was no significant heterogeneity in the direct paired comparisons,and there were no significant differences in the inclusion or exclusion criteria,intervention measures,or outcome indicators,meeting the assumptions of heterogeneity and transitivity.OS analysis revealed that patients who underwent stereotactic body radiotherapy(SBRT)after resection had longer OS than those who underwent intensity modulated radiotherapy(IMRT)or 3-dimensional conformal RT(3D-CRT).DFS analysis revealed that patients who underwent 3D-CRT after resection had the longest DFS.Patients who underwent IMRT after resection had longer OS than those who underwent 3D-CRT and longer DFS than those who underwent SBRT.CONCLUSION HCC patients who undergo liver cancer resection must consider distinct advantages and disadvantages when choosing between SBRT and 3D-CRT.IMRT,a RT technique that is associated with longer OS than 3D-CRT and longer DFS than SBRT,may be a preferred option. 展开更多
关键词 Primary liver cancer Hepatocellular carcinoma Network meta-analysis External beam radiation therapy Stereotactic body radiotherapy Intensity modulated radiotherapy
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Radiation of a TM mode from an open end of a three-layer dielectric capillary
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作者 Sergey NGalyamin Alexandr MAltmark 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期311-318,共8页
Modern trends in beam-driven radiation sources include the interaction of Cherenkov wakefields in open-ended circular waveguides with complicated dielectric linings, with a three-layer dielectric capillary recently pr... Modern trends in beam-driven radiation sources include the interaction of Cherenkov wakefields in open-ended circular waveguides with complicated dielectric linings, with a three-layer dielectric capillary recently proposed to reduce radiation divergence being a representative example [Opt. Lett. 45 5416(2020)]. We present a rigorous approach that allows for an analytical description of the electromagnetic processes that occur when the structure is excited by a single waveguide TM mode. In other words, the corresponding canonical waveguide diffraction problem is solved in a rigorous formulation. This is a continuation of our previous papers which considered simpler cases with a homogeneous or two-layer dielectric filling. Here we use the same analytical approach based on the Wiener–Hopf–Fock technique and deal with the more complicated case of a three-layer dielectric lining. Using the obtained rigorous solution, we discuss the possibility of manipulating the far-field radiation pattern using a third layer made of a low permittivity material. 展开更多
关键词 diffraction radiation open-ended waveguide Wiener–Hopf technique Cherenkov radiation
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Nano-silica modified lightweight and high-toughness carbon fiber/phenolic ablator with excellent thermal insulation and ablation performance
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作者 Wenjie Xu Wenda Song +4 位作者 Xianfeng Jia Cheng Ma Jitong Wang Wenming Qiao Licheng Ling 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期192-199,共8页
Lightweight and high-toughness carbon fiber/phenolic ablator(CFPA)is required as the Thermal Protection System(TPS)material of aerospace vehicles for next-generation space missions.To improve the ablative properties,s... Lightweight and high-toughness carbon fiber/phenolic ablator(CFPA)is required as the Thermal Protection System(TPS)material of aerospace vehicles for next-generation space missions.To improve the ablative properties,silica sol with good particle size distribution prepared using tetramethoxysilane(TMOS)was blended with natural rubber latex and deposited onto carbon fiber felt,which was then integrated with phenolic aerogel matrix,introducing nano-silica into the framework of CFPA.The modified CFPA with a low density of 0.28—0.31 g/cm3exhibits strain-in-fracture as high as 31.2%and thermal conductivity as low as 0.054 W/(m·K).Furthermore,a trace amount of nano-silica could effectively protect CFPA from erosion of oxidizing atmosphere in different high-temperature environments.The oxyacetylene ablation test of 3000°C for 20 s shows a mass ablation rate of 0.0225 g/s,a linear ablation rate of 0.209 mm/s for the modified CFPA,which are 9.64%and 24.82%lower than the unmodified one.Besides,the long-time butane ablation test of 1200°C for 200 s shows an insignificant recession with mass and linear ablation rate of 0.079 g/s and 0.039 mm/s,16.84%and 13.33%lower than the unmodified one.Meanwhile,the fixed thermocouple in the test also demonstrates a good thermal insulation performance with a low peak back-face temperature of 207.7°C,12.25%lower than the unmodified one.Therefore,the nano-silica modified CFPA with excellent overall performance presents promising prospects in high-temperature aerospace applications. 展开更多
关键词 NANO-SILICA Carbonfiber Phenolic aerogel Insulation ablation
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Effect of sample temperature on femtosecond laser ablation of copper
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作者 党伟杰 陈雨桐 +1 位作者 陈安民 金明星 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期377-385,共9页
We conduct an experimental study supported by theoretical analysis of single laser ablating copper to investigate the interactions between laser and material at different sample temperatures,and predict the changes of... We conduct an experimental study supported by theoretical analysis of single laser ablating copper to investigate the interactions between laser and material at different sample temperatures,and predict the changes of ablation morphology and lattice temperature.For investigating the effect of sample temperature on femtosecond laser processing,we conduct experiments on and simulate the thermal behavior of femtosecond laser irradiating copper by using a two-temperature model.The simulation results show that both electron peak temperature and the relaxation time needed to reach equilibrium increase as initial sample temperature rises.When the sample temperature rises from 300 K to 600 K,the maximum lattice temperature of the copper surface increases by about 6500 K under femtosecond laser irradiation,and the ablation depth increases by 20%.The simulated ablation depths follow the same general trend as the experimental values.This work provides some theoretical basis and technical support for developing femtosecond laser processing in the field of metal materials. 展开更多
关键词 femtosecond laser two-temperature model sample temperature ablation depth
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Simulation of deuterium pellet ablation and deposition in the EAST tokamak with HPI2 code
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作者 李大正 张洁 +2 位作者 侯吉磊 李懋 孙继忠 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期561-569,共9页
Pellet injection is a primary method for fueling the plasma in magnetic confinement devices.For that goal the knowledges of pellet ablation and deposition profiles are critical.In the present study,the pellet fueling ... Pellet injection is a primary method for fueling the plasma in magnetic confinement devices.For that goal the knowledges of pellet ablation and deposition profiles are critical.In the present study,the pellet fueling code HPI2 was used to predict the ablation and deposition profiles of deuterium pellets injected into a typical H-mode discharge on the EAST tokamak.Pellet ablation and deposition profiles were evaluated for various pellet injection locations,with the aim at optimizing the pellet injection to obtain a deep fueling depth.In this study,we investigate the effect of the injection angle on the deposition depth of the pellet at different velocities and sizes.The ablation and deposition of the injected pellet are mainly studied at each injection position for three different injection angles:0°,45°,and 60°.The pellet injection on the high field side(HFS)can achieve a more ideal deposition depth than on the low field side(LFS).Among these angles,horizontal injection on the middle plane is relatively better on either the HFS or the LFS.When the injection location is 0.468 m below the middle plane on the HFS or 0.40 m above the middle plane of the LFS,it can achieve a similar deposition depth to the one of its corresponding side.When the pre-cooling effect is taken into account,the deposition depth is predicted to increase only slightly when the pellet is launched from the HFS.The findings of this study will serve as a reference for the update of pellet injection systems for the EAST tokamak. 展开更多
关键词 pellet injection pellet ablation HPI2 pellet deposition
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Microstructure and ablation behavior of Zr-based ultra-high-temperature gradient composites
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作者 Qing-hua LIU Tian TIAN +2 位作者 Wei SUN Hong-bo ZHANG Xiang XIONG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2889-2899,共11页
To obtain high-performance Zr-based ultra-high-temperature composites,Zr-based ultra-high-temperature gradient composites were prepared by changing the laying method of the infiltrant via reactive melt infiltration.Th... To obtain high-performance Zr-based ultra-high-temperature composites,Zr-based ultra-high-temperature gradient composites were prepared by changing the laying method of the infiltrant via reactive melt infiltration.The effects of different infiltrant laying methods on the microstructure and ablative properties of Zr-based ultrahigh-temperature gradient composites were investigated.The results showed that the gradient structure of the Zr-based ultrahigh-temperature gradient composites differed when the composition ratio of the infiltrant was changed.When the thicknesses of the Zr/Mo/Si layers were 6/4/12 mm and 8/2/12 mm,the SiMoZrC solid solution content in the samples increased and decreased along the infiltration direction,respectively.The gradient samples were ablated in an oxyacetylene flame at 3000°C for 40 s.The ablation resistance of the sample was the highest when the infiltrant was a powder and the thickness of the Zr/Mo/Si layer was 6/4/12 mm. 展开更多
关键词 reactive melt infiltration ceramic-matrix composites gradient material MICROSTRUCTURE ablation property
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Transperineal laser ablation of the prostate as a treatment for benign prostatic hyperplasia and prostate cancer: The results of a Delphi consensus project
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作者 Andrea Cocci Marta Pezzoli +35 位作者 Fernando Bianco Franco Blefari Pierluigi Bove Francois Cornud Gaetano De Rienzo Paolo Destefanis Danilo Di Trapani Alessandro Giacobbe Luca Giovanessi Antonino Laganà Giovanni Lughezzani Guglielmo Manenti Gianluca Muto Gianluigi Patelli Novello Pinzi Stefano Regusci Giorgio I.Russo Juan I.M.Salamanca Matteo Salvi Luigi Silvestri Fabrizio Verweij Eric Walser Riccardo GBertolo Valerio Iacovelli Alessandro Bertaccini Debora Marchiori Hugo Davila Pasquale Ditonno Paolo Gontero Gennaro Iapicca Theo M De Reijke Vito Ricapito Pierluca Pellegrini Andrea Minervini Sergio Serni Francesco Sessa 《Asian Journal of Urology》 CSCD 2024年第2期271-279,共9页
Objective: To evaluate transperineal laser ablation (TPLA) with Echolaser® (Echolaser® TPLA, Elesta S.p.A., Calenzano, Italy) as a treatment for benign prostatic hyperplasia (BPH) and prostate cancer (PCa) u... Objective: To evaluate transperineal laser ablation (TPLA) with Echolaser® (Echolaser® TPLA, Elesta S.p.A., Calenzano, Italy) as a treatment for benign prostatic hyperplasia (BPH) and prostate cancer (PCa) using the Delphi consensus method.Methods: Italian and international experts on BPH and PCa participated in a collaborative consensus project. During two rounds, they expressed their opinions on Echolaser® TPLA for the treatment of BPH and PCa answering online questionnaires on indications, methodology, and potential complications of this technology. Level of agreement or disagreement to reach consensus was set at 75%. If the consensus was not achieved, questions were modified after each round. A final round was performed during an online meeting, in which results were discussed and finalized.Results: Thirty-two out of forty invited experts participated and consensus was reached on all topics. Agreement was achieved on recommending Echolaser® TPLA as a treatment of BPH in patients with ample range of prostate volume, from <40 mL (80%) to >80 mL (80%), comorbidities (100%), antiplatelet or anticoagulant treatment (96%), indwelling catheter (77%), and strong will of preserving ejaculatory function (100%). Majority of respondents agreed that Echolaser® TPLA is a potential option for the treatment of localized PCa (78%) and recommended it for low-risk PCa (90%). During the final round, experts concluded that it can be used for intermediate-risk PCa and it should be proposed as an effective alternative to radical prostatectomy for patients with strong will of avoiding urinary incontinence and sexual dysfunction. Almost all participants agreed that the transperineal approach of this organ-sparing technique is safer than transrectal and transurethral approaches typical of other techniques (97% of agreement among experts). Pre-procedural assessment, technical aspects, post-procedural catheterization, pharmacological therapy, and expected outcomes were discussed, leading to statements and recommendations.Conclusion: Echolaser® TPLA is a safe and effective procedure that treats BPH and localized PCa with satisfactory functional and sexual outcomes. 展开更多
关键词 Transperineal laser ablation Prostatecancer Benignprostatic hyperplasia Delphi consensus
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Benefits and drawbacks of radiofrequency ablation via percutaneous or minimally invasive surgery for treating hepatocellular carcinoma
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作者 Ching-Lung Hsieh Cheng-Ming Peng +3 位作者 Chun-Wen Chen Chang-Hsien Liu Chih-Tao Teng Yi-Jui Liu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第11期3400-3407,共8页
The management of early stage hepatocellular carcinoma(HCC)presents significant challenges.While radiofrequency ablation(RFA)has shown safety and effectiveness in treating HCC,with lower mortality rates and shorter ho... The management of early stage hepatocellular carcinoma(HCC)presents significant challenges.While radiofrequency ablation(RFA)has shown safety and effectiveness in treating HCC,with lower mortality rates and shorter hospital stays,its high recurrence rate remains a significant impediment.Consequently,achieving improved survival solely through RFA is challenging,particularly in retrospective studies with inherent biases.Ultrasound is commonly used for guiding percutaneous RFA,but its low contrast can lead to missed tumors and the risk of HCC recurrence.To enhance the efficiency of ultrasound-guided percutaneous RFA,various techniques such as artificial ascites and contrast-enhanced ultrasound have been developed to facilitate complete tumor ablation.Minimally invasive surgery(MIS)offers advantages over open surgery and has gained traction in various surgical fields.Recent studies suggest that laparoscopic intraoperative RFA(IORFA)may be more effective than percutaneous RFA in terms of survival for HCC patients unsuitable for surgery,highlighting its significance.Therefore,combining MIS-IORFA with these enhanced percutaneous RFA techniques may hold greater significance for HCC treatment using the MIS-IORFA approach.This article reviews liver resection and RFA in HCC treatment,comparing their merits and proposing a trajectory involving their combination in future therapy. 展开更多
关键词 Percutaneous radiofrequency ablation Minimally invasive surgery Hepatocellular carcinoma Intraoperative radiofrequency ablation Contrast-enhanced ultrasound
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Flexibility potential of Cs_(2)BX_(6)(B=Hf,Sn,Pt,Zr,Ti;X=I,Br,Cl)with application in photovoltaic devices and radiation detectors
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作者 Songya Wang Changcheng Chen +11 位作者 Shaohang Shi Ziyi Zhang Yan Cai Shuli Gao Wen Chen Shuangna Guo Elyas Abduryim Chao Dong Xiaoning Guan Ying Liu Gang Liu Pengfei Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期271-287,I0006,共18页
As interest in double perovskites is growing,especially in applications like photovoltaic devices,understanding their mechanical properties is vital for device durability.Despite extensive exploration of structure and... As interest in double perovskites is growing,especially in applications like photovoltaic devices,understanding their mechanical properties is vital for device durability.Despite extensive exploration of structure and optical properties,research on mechanical aspects is limited.This article builds a vacancyordered double perovskite model,employing first-principles calculations to analyze mechanical,bonding,electronic,and optical properties.Results show Cs_(2)Hfl_(6),Cs_(2)SnBr_(6),Cs_(2)SnI_(6),and Cs_(2)PtBr_(6)have Young's moduli below 13 GPa,indicating flexibility.Geometric parameters explain flexibility variations with the changes of B and X site composition.Bonding characteristic exploration reveals the influence of B and X site electronegativity on mechanical strength.Cs_(2)SnBr_(6)and Cs_(2)PtBr_(6)are suitable for solar cells,while Cs_(2)HfI_(6)and Cs_(2)TiCl_(6)show potential for semi-transparent solar cells.Optical property calculations highlight the high light absorption coefficients of up to 3.5×10^(5) cm^(-1)for Cs_(2)HfI_(6)and Cs_(2)TiCl_(6).Solar cell simulation shows Cs_(2)PtBr_(6)achieves 22.4%of conversion effciency.Cs_(2)ZrCl_(6)holds promise for ionizing radiation detection with its 3.68 eV bandgap and high absorption coefficient.Vacancy-ordered double perovskites offer superior flexibility,providing valuable insights for designing stable and flexible devices.This understanding enhances the development of functional devices based on these perovskites,especially for applications requiring high stability and flexibility. 展开更多
关键词 Double perovskite Mechanical properties Flexible PHOTOVOLTAIC radiation detectors
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Efficacy of radiofrequency ablation combined with sorafenib for treating liver cancer complicated with portal hypertension and prognostic factors
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作者 Li-Min Yang Hong-Juan Wang +4 位作者 Shan-Lin Li Guan-Hua Gan Wen-Wen Deng Yong-Sheng Chang Lian-Feng Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第11期1533-1544,共12页
BACKGROUND Patients with liver cancer complicated by portal hypertension present complex challenges in treatment.AIM To evaluate the efficacy of radiofrequency ablation in combination with sorafenib for improving live... BACKGROUND Patients with liver cancer complicated by portal hypertension present complex challenges in treatment.AIM To evaluate the efficacy of radiofrequency ablation in combination with sorafenib for improving liver function and its impact on the prognosis of patients with this condition.METHODS Data from 100 patients with liver cancer complicated with portal hypertension from May 2014 to March 2019 were analyzed and divided into a study group(n=50)and a control group(n=50)according to the treatment regimen.The research group received radiofrequency ablation(RFA)in combination with sorafenib,and the control group only received RFA.The short-term efficacy of both the research and control groups was observed.Liver function and portal hypertension were compared before and after treatment.Alpha-fetoprotein(AFP),glypican-3(GPC-3),and AFP-L3 levels were compared between the two groups prior to and after treatment.The occurrence of adverse reactions in both groups was observed.The 3-year survival rate was compared between the two groups.Basic data were compared between the survival and non-surviving groups.To identify the independent risk factors for poor prognosis in patients with liver cancer complicated by portal hypertension,multivariate logistic regression analysis was employed.RESULTS When comparing the two groups,the research group's total effective rate(82.00%)was significantly greater than that of the control group(56.00%;P<0.05).Following treatment,alanine aminotransferase and aspartate aminotransferase levels increased,and portal vein pressure decreased in both groups.The degree of improvement for every index was substantially greater in the research group than in the control group(P<0.05).Following treatment,the AFP,GPC-3,and AFP-L3 levels in both groups decreased,with the research group having significantly lower levels than the control group(P<0.05).The incidence of diarrhea,rash,nausea and vomiting,and fatigue in the research group was significantly greater than that in the control group(P<0.05).The 1-,2-,and 3-year survival rates of the research group(94.00%,84.00%,and 72.00%,respectively)were significantly greater than those of the control group(80.00%,64.00%,and 40.00%,respectively;P<0.05).Significant differences were observed between the survival group and the non-surviving group in terms of Child-Pugh grade,history of hepatitis,number of tumors,tumor size,use of sorafenib,stage of liver cancer,histological differentiation,history of splenectomy and other basic data(P<0.05).Logistic regression analysis demonstrated that high Child-Pugh grade,tumor size(6–10 cm),history of hepatitis,no use of sorafenib,liver cancer stage IIIC,and previous splenectomy were independent risk factors for poor prognosis in patients with liver cancer complicated with portal hypertension(P<0.05).CONCLUSION Patients suffering from liver cancer complicated by portal hypertension benefit from the combination of RFA and sorafenib therapy because it effectively restores liver function and increases survival rates.The prognosis of patients suffering from liver cancer complicated by portal hypertension is strongly associated with factors such as high Child-Pugh grade,tumor size(6-10 cm),history of hepatitis,lack of sorafenib use,liver cancer at stage IIIC,and prior splenectomy. 展开更多
关键词 Radiofrequency ablation SORAFENIB Liver cancer Portal hypertension EFFICACY Prognosis analysis
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Visualizing the Spin & Radiation of the Extended Electron in Magnetic Field
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作者 Hoa Van Nguyen 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期277-291,共15页
This article presents illustrations of an extended model of the electron to visualize how it spins and radiates in the external magnetic field. A time-varying magnetic field B produces a rotational induced electric fi... This article presents illustrations of an extended model of the electron to visualize how it spins and radiates in the external magnetic field. A time-varying magnetic field B produces a rotational induced electric field E which rotates (spins) the electron about its axis. In time-constant magnetic field: the electron radiates the cyclotron radiation. In time-varying magnetic field: synchrotron radiation is generated. The couplings between spin, acceleration and radiation will be discussed. 展开更多
关键词 Spinning Forces Spin by Inertia Radiating Forces Photon or Static Electric Dipole Cloud of Photons Spin - radiation Coupling
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Heuristic Estimation of the Vacuum Energy Density of the Universe: Part II-Analysis Based on Frequency Domain Electromagnetic Radiation
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作者 Vernon Cooray Gerald Cooray +1 位作者 Marcos Rubinstein Farhad Rachidi 《Journal of Electromagnetic Analysis and Applications》 2024年第1期1-9,共9页
In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according ... In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according to which an electron is accelerated to a constant and relativistic speed at a distance L from a perfectly conducting plane. The charge of the electron was represented by a spherical charge distribution located within the Compton wavelength of the electron. Subsequently, the electron is incident on the perfect conductor giving rise to transition radiation. The energy associated with the transition radiation depends on the parameter L. It was shown that an inequality satisfied by the vacuum energy density will emerge when the length L is pushed to cosmological dimensions and the product of the radiated energy, and the time duration of emission is constrained by Heisenberg’s uncertainty principle. In this paper, a similar analysis is conducted with a chain of electrons oscillating sinusoidally and located above a conducting plane. In the thought experiment presented in this paper, the behavior of the energy radiated by the chain of oscillating electrons is studied in the frequency domain as a function of the length L of the chain. It is shown that when the length L is pushed to cosmological dimensions and the energy radiated within a single burst of duration of half a period of oscillation is constrained by the fact that electromagnetic energy consists of photons, an inequality satisfied by the vacuum energy density emerges as a result. The derived inequality is given by where is the vacuum energy density. This result is consistent with the measured value of the vacuum energy density, which is 5.38 × 10<sup>-10</sup> J/m. The result obtained here is in better agreement with experimental data than the one obtained in Part I of this paper with time domain radiation. 展开更多
关键词 Classical Electrodynamics Electromagnetic radiation Action Radiated Energy PHOTON Heisenberg’s Uncertainty Principle Dark Energy Vacuum Energy Cosmological Constant Hubble Radius
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Progress of Radiation Belt Exploration by a Constellation of Small Satellites TGCSS/SGRB, COSPAR
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作者 WU Ji YANG Xiaochao +1 位作者 DAI Lei DENG Li 《空间科学学报》 CAS CSCD 北大核心 2024年第4期746-750,共5页
A COnstellation of Radiation BElt Survey(CORBES)program is proposed by the Sub-Group on Radiation Belt(SGRB)of TGCSS,COSPAR.To address the open qustions about the dynamics of the Earth’s radiation belt,CORBES mission... A COnstellation of Radiation BElt Survey(CORBES)program is proposed by the Sub-Group on Radiation Belt(SGRB)of TGCSS,COSPAR.To address the open qustions about the dynamics of the Earth’s radiation belt,CORBES mission would use a constellation of small/CubeSats to take an ultra-fast survey of the Earth’s radiation belt.The concept,science objectives and preliminary technical design of CORBES are introduced.This mission is an international multilateral cooperation mission coordinated by COSPAR.The SGRB Science Activities and COSPAR HQs Coordinate Activities on CORBES are summaried. 展开更多
关键词 radiation belts Ultra-fast survey CONSTELLATION
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