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Evaluation of the prognostic nutritional index for the prognosis of Chinese patients with high/extremely high-risk prostate cancer after radical prostatectomy 被引量:3
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作者 Fan Yang Min Pan +2 位作者 Jin Nie Fan Xiao Yuan Zhang 《World Journal of Clinical Cases》 SCIE 2022年第25期8863-8871,共9页
BACKGROUND The incidence of prostate cancer(PCa)is on the rise in China.The risk level of patients with PCa is associated with disease-free survival rate at 10 years after radical prostatectomy.Predicting prognosis in... BACKGROUND The incidence of prostate cancer(PCa)is on the rise in China.The risk level of patients with PCa is associated with disease-free survival rate at 10 years after radical prostatectomy.Predicting prognosis in advance according to the degree of risk can provide a reference for patients,especially treatment options and postoperative adjuvant treatment measures for high-risk/extremely high-risk patients.AIM To explore the predictive value of the prognostic nutritional index(PNI)for biological recurrence in Chinese patients with high/extremely high-risk PCa after radical prostatectomy.METHODS The biochemical test results and clinical data of 193 patients who underwent radical prostatectomy for the first time from January 2015 to December 2020 were retrospectively collected.The PNI value of peripheral blood within 1 wk before surgery was calculated,and during the follow-up period,prostate-specific antigen≥0.2 ng/mL was considered to have biological recurrence.The receiver operating characteristic(ROC)curve was used to calculate the optimal critical value and area under the curve(AUC)of the patients.According to the critical value,the progression-free survival of the high PNI group and low PNI group was compared.The independent influencing factors of the patients’prognosis were obtained by the Cox proportional hazards regression model.RESULTS The non-biological recurrence rates at 1,3,and 5 years were 92.02%,84.05%,and 74.85%,respectively.The optimal critical value for PNI to predict biological recurrence was 46.23,and the AUC was 0.789(95%confidence interval:0.651-0.860;P<0.001).The sensitivity and specificity were 82.93%and 62.30%,respectively.In accordance with the optimal critical value of the ROC curve(46.23),193 patients were further divided into a high PNI group(PNI≤46.23,n=108)and low PNI group(PNI>46.23,n=85).The incidence of postoperative complications in the high PNI group was lower than that in the low PNI group(21.18%vs 38.96%).Kaplan-Meier survival analysis showed that the overall survival rate at 5 years in the low PNI group was 87.96%(13/108),which was lower than that in the high PNI group(61.18%,33/85;P<0.05).Low PNI[hazard ratio(HR)=1.74;P=0.003]and positive incisal margin status(HR=2.14;P=0.001)were independent predictors of biological recurrence in patients with high/extremely high-risk PCa.CONCLUSION The PNI has predictive value for the prognosis of patients with high/extremely high-risk PCa,and is an independent prognostic factor.Patients with low PNI value have a shorter time of nonbiological recurrence after prostatectomy.It is expected that the combined prediction of other clinicopathological data will further improve the accuracy and guide postoperative adjuvant therapy to improve the quality of prognosis. 展开更多
关键词 high/extremely high-risk Prostate cancer Prognostic nutrition index Prognostic evaluation Radical prostatectomy
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Key technologies for construction of Jinping traffic tunnel with an extremely deep overburden and a high water pressure 被引量:6
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作者 Shougen CHEN Heng ZHANG Xinrong TAN Liang CHEN 《Journal of Modern Transportation》 2011年第2期94-103,共10页
Jinping traffic tunnel is one of the deepest traffic tunnels in the world with a maximum overburden of 2 375 m and the overburden over 73% of its total length is larger than 1 500 m. The tunnel is 17.5 km long and des... Jinping traffic tunnel is one of the deepest traffic tunnels in the world with a maximum overburden of 2 375 m and the overburden over 73% of its total length is larger than 1 500 m. The tunnel is 17.5 km long and designed to provide a shortcut road between two hydropower stations: Jinping I and Jinping II of the Jinping Hydropower Project, located on Yalong River, Liangshan State, Sichuan Province, China. The tunnel is so deep that building any shafts is impossible. The construction starts from both ends (east and west ends), and the construction length from the west end is 10 km with a blind heading. This paper deals with an overview of this project and analysis of the engineering features, as well as key technologies developed and applied during the construction, including geological prediction, rock burst prevention under a super high in-situ stress, sealing of groundwater with a high pressure and big flow rate, ventilation for a blind heading of 10 km, wet spraying of shotcrete at zones of rock burst and rich water, etc. The application of the new technologies to the construction achieved a high quality tunnel within the contract period. 展开更多
关键词 key technologies Jinping traffic tunnel extremely deep overburden high water pressure
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EXTREMELY HIGH FREQUENCY (EHF) PUNCTURE THERAPY AND SYNDROMES OF TRADITIONAL CHINESE MEDICINE 被引量:1
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作者 MikhailTeppone AlexeyKrotenko 《World Journal of Acupuncture-Moxibustion》 1996年第1期9-16,共8页
ExtremeIy high frequency (EHF) puncture is a new method of treatment based uponbiological effects of low power electromagnetic waves of millimetric band and acupuncture theory oftraditional Chinese medicine (TCM). It ... ExtremeIy high frequency (EHF) puncture is a new method of treatment based uponbiological effects of low power electromagnetic waves of millimetric band and acupuncture theory oftraditional Chinese medicine (TCM). It is non-invasive, painless and effective. Extensiveness and variety of the specific sensations (Deqi phenomenon) during EHF-puncture re-flect intensive reactions of the patient’s organism and provide individualization of therapy. EHF-puncture is a step of integration of traditional Chinese with modern Western medicines. 展开更多
关键词 extremely high frquency THERAPY Syndrome of TCM MILLIMETER electromagnetic radiation
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AcrySof phakic angle-supported intraocular lens for the correction of high to extremely high myopia:one-year follow-up results 被引量:2
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作者 Rui-Bo Yang Shao-Zhen Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2012年第3期360-365,共6页
AIM: To assess the safety, efficacy and predictability of the AcrySof phakic angle-supported intraocular lens (IOL) (Alcon Inc., U.S.A.) for correction of high-to-extremely high myopia in adults. METHODS: In this pros... AIM: To assess the safety, efficacy and predictability of the AcrySof phakic angle-supported intraocular lens (IOL) (Alcon Inc., U.S.A.) for correction of high-to-extremely high myopia in adults. METHODS: In this prospective study performed in Tianjin Medical University Eye Center & College of Optometry, Tianjin, China, 25 eyes of 13 patients were implanted with AcrySof phakic angle-supported IOLs and followed for 1 year postoperatively. Preoperative manifest refractive sphere was (-12.08 +/- 2.44) diopters (D) and cylinder was (-1.35 +/- 0.62)D. Visual acuity, predictability and stability of manifest refraction spherical equivalent (MRSE), adverse events, and endothelial cell density were analyzed during 1-year of follow-up. RESULTS: After 1 year of follow-up, no eyes lost 1 line (best spectacle-corrected visual acuity)BSCVA; an uncorrected visual acuity (UCVA) of 20/20 or better was achieved in 60% of eyes; 100% had an UCVA of 20/40 or better; a BSCVA of 20/30 or better was achieved by 100% of eyes; 84% had a BSCVA of 20/20 or better. The overall mean percentage change in endothelial cell density 1 year after surgery was (-0.27 +/- 3.60)%. Two eyes (8%) had increased intraocular pressure (IOP) on the day of surgery. No pupil ovalization, pupillary block, or retinal detachment events were observed. CONCLUSION: After 1 year of follow-up, the implantation of AcrySof phakic angle-supported IOL is proved to be safe, effective and predictable with minimal complications in patients with high-to-extremely high myopia. Due to the limitation of visiting time, long-term of clinical investigation is necessary to verify the safety and efficacy of this IOL. 展开更多
关键词 phakic eye lens INTRAOCULAR high myopia foldable angle-supported
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Circulation anomalies in the mid–high latitudes responsible for the extremely hot summer of 2018 over northeast Asia 被引量:12
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作者 XU Ke LU Riyu +1 位作者 MAO Jiangyu CHEN Ruidan 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第4期231-237,共7页
This study investigated the contributions of mid–high-latitude circulation anomalies to the extremely hot summer(July and August;JA)of 2018 over Northeast Asia(NEA).The JA-mean surface air temperature in 2018 was 1.2... This study investigated the contributions of mid–high-latitude circulation anomalies to the extremely hot summer(July and August;JA)of 2018 over Northeast Asia(NEA).The JA-mean surface air temperature in 2018 was 1.2°C higher than that of the 1979–2018 climatology,with the amplitude of such an anomaly almost doubling the interannual standard deviation,making 2018 the hottest year during the analysis period 1979–2018.The abnormal warming over NEA was caused by a local positive geopotential height anomaly reaching strongest intensity in JA 2018.Further investigation suggested that the upper-tropospheric circulation anomalies over northern Europe and the Caspian Sea were crucial to forming this NEA circulation anomaly through initiating downstream wave trains.Particularly,the geopotential heights over these two regions were concurrently at their highest in JA 2018,and therefore jointly contributed to the profound circulation anomaly over NEA and the hottest summer on record.Due to these two teleconnection patterns,the temperature anomalies in NEA are closely related to those in both northern Europe and the Caspian Sea,where the similarly extreme warming also happened in 2018. 展开更多
关键词 Northeast Asia summer temperature mid–high latitudes circulation anomalies
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High?Voltage Flexible Aqueous Zn?Ion Battery with Extremely Low Dropout Voltage and Super?Flat Platform 被引量:2
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作者 Zhe Chen Panpan Wang +5 位作者 Zhenyuan Ji Hua Wang Jie Liu Jiaqi Wang Mengmeng Hu Yan Huang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第6期126-137,共12页
Flexible rechargeable aqueous zinc-ion batteries(ZIBs)have attracted extensive attentions in the energy storage field due to their high safety,environmental friendliness,and outstanding electrochemical performance whi... Flexible rechargeable aqueous zinc-ion batteries(ZIBs)have attracted extensive attentions in the energy storage field due to their high safety,environmental friendliness,and outstanding electrochemical performance while the exploration of high-voltage aqueous ZIBs with excellent rate capability is still a great challenge for the further application them in flexible and wearable electronics.Herein,we fabricated a 2.4 V high-voltage flexible aqueous ZIB,being among the highest voltage reported in aqueous ZIBs.Moreover,it exhibits extremely flat charging/discharging voltage platforms and the dropout voltage is only 0.1 V,which is the smallest gap in all aqueous batteries to our best knowledge.Furthermore,the prepared ZIB performs high rate capability of 25 C and energy density of 120 Wh kg?1 and exhibits excellent safety under various destructive conditions including hammering,sewing,punching,and soaking.These extraordinary results indicate the great application potential of our high-voltage flexible aqueous ZIB in wearable electronics. 展开更多
关键词 Flexible AQUEOUS zinc-ion BATTERY high VOLTAGE FLAT PLATFORM Rate capability
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Effect of the Blocking High-East Asian Trough on Three Extreme Cold Events in Eastern Asia
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作者 Ziqun ZHANG Hongyan CUI +4 位作者 Fangli QIAO Baoxu CHEN Yang SONG Xiaohui SUN Chang GAO 《Advances in Atmospheric Sciences》 2025年第5期892-903,共12页
Three extreme cold events occurred in eastern Asia in January 2016,January 2021,and December 2023.As important factors in atmospheric circulation anomalies,the Blocking High and East Asian Trough(BH-ET)structure playe... Three extreme cold events occurred in eastern Asia in January 2016,January 2021,and December 2023.As important factors in atmospheric circulation anomalies,the Blocking High and East Asian Trough(BH-ET)structure played key roles during these three extreme cold wave events.Among these two dynamic patterns,the BH affected the development of the cold waves in two different ways:(1)before the cold waves in 2016 and 2023,the BH pushed the cold air southward,resulting in a slow and gradual cooling,with a cooling rate(CR)in eastern Asia of 1.34℃d^(-1)and 1.2℃d^(-1),respectively,and(2)in January 2021,the sudden collapse of BH caused the cold air to rapidly attack mid-latitude regions,with a CR of 1.87℃d^(-1).In terms of the spatial CR,the temperature drop in 2021 occurred 38.8%and 55%faster than those in 2016 and 2023,respectively.At the same time,the ET influences the wind direction of cold waves by modulating the pressure gradient.Before the cold waves occurred,the meridional wind field near the ET showed negative values,forming northwesterly or northeasterly winds,which continued to affect the southern part of East Asia.The meridional wind in January 2021 was stronger than those in 2016 and 2023,which is thought to be the reason for the strength of the 2021 cold wave.Finally,results from the temperature Empirical Orthogonal Function(EOF)analysis from 1980-2023 verify an obvious BH-ET structure in the three cold wave events,which suggests that this particular climatological state provides a climatic background for the occurrence of cold waves. 展开更多
关键词 extreme cold waves blocking high East Asian trough cooling rate
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Co-Production of High-Grade Dissolving Pulp,Furfural,and Lignin from Eucalyptus via Extremely Low Acid Pretreatment and Pulping Technologies and Catalysis 被引量:1
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作者 Chengxiang Li Yue Wu +3 位作者 Chunhui Zhang Yao Liu Qixuan Lin Junli Ren 《Journal of Renewable Materials》 SCIE EI 2023年第6期2555-2574,共20页
Hemicellulose and lignin are not reasonably utilized during the dissolved pulp preparation process.This work aimed to propose a process for the co-production of dissolving pulp,furfural,and lignin from eucalyptus.High... Hemicellulose and lignin are not reasonably utilized during the dissolved pulp preparation process.This work aimed to propose a process for the co-production of dissolving pulp,furfural,and lignin from eucalyptus.High-grade dissolving pulp was prepared from eucalyptus using a combination of extremely low acid(ELA)pretreatment,Kraft cooking,and elementary chlorine-free(ECF)bleaching.The obtained pre-hydrolysate was catalytic conversion into furfural in a biphasic system,and lignin during Kraft cooking and ECF was recovered.The process condition was discussed as well as the mass flow direction.The results showed that ELA pretreatment could effectively remove 80.1%hemicellulose.Compared with traditional hydrothermal pretreatment,the ELA pretreatment significantly increased the xylose yield from 5.05 to 14.18 g/L at 170℃ for 2 h,which had practical significance for furfural production.The 82.7%furfural yield and 82.9%furfural selectivity were obtained from xylose-rich pre-hydrolysate using NaCl as a phase modifier in a biphasic system with 4-methyl-2-pentanone(MIBK)as an organic phase by ion exchange resin catalysts at 190℃ for 2 h.Subsequently,the pretreated eucalyptus was subjected to Kraft cooking,and the optimal alkali amount was 14%.Then,the Kraft pulp was bleached using the O-D1-EP-D_(2) sequence,and dissolving pulp was obtained with an ISO brightness of 86.0%,viscosity of 463 mL/g,andα-cellulose content of 95.4%.The Kraft lignin which has a potential application was investigated by 2D-HSQC NMR and 31P NMR.The results showed that the S/G ratio of Kraft lignin was 1.93,and the content of phenolic hydroxyl groups was 2.53 mmol/g.Moreover,based on the above proposed process,30.5 g dissolving pulp,5.5 g furfural,and 21.2 g lignin per 100 g eucalyptus chips(oven dry)were produced.This research will provide new catalysis and pulping technical routes for dissolving pulp,furfural,and Kraft lignin products,which are in great demand in the chemical industry. 展开更多
关键词 EUCALYPTUS extremely low acid pretreatment dissolving pulp FURFURAL kraft lignin
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Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures
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作者 Jie Bai Jian Hui Jia +2 位作者 Yu Wang Chun Cheng Yang Qing Jiang 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期152-167,共16页
Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or lower.However,the key capability o... Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or lower.However,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely reported.Herein,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock method.Such a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1) at 2 A g^(−1))at−60℃,outperforming all reported SIB anode materials.Coupled with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1) at−40°C.Based on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current. 展开更多
关键词 Bi nanoparticles high temperature shock high-rate activation Ultrafast charging Low-temperature sodium-ion batteries
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Synergistic Influences from High,Middle,and Low Latitudes on the Extreme Precipitation Events in the Beijing-Tianjin-Hebei Region During the Summer of 2023
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作者 YU Peiyi QIAN Shengyi +4 位作者 HU Haibo HE Shengping XIONG Yijie FU Tianxiang WANG Yu 《Journal of Ocean University of China》 2025年第5期1157-1168,共12页
East Asia is a region characterized by a typical monsoon climate,which is accompanied by strong precipitation with complex spatiotemporal variability during summer.Previous works have emphasized the impact of tropical... East Asia is a region characterized by a typical monsoon climate,which is accompanied by strong precipitation with complex spatiotemporal variability during summer.Previous works have emphasized the impact of tropical signals on extreme summer precipitation over East Asia,but the roles of the mid-high latitude cyclones are still unclear.Using a reanalysis dataset,this study discloses the synergistic influences of anomalous signals from different latitudes on the extreme precipitation event in the Beijing-Tianjin-Hebei(BTH)region during the summer of 2023.The main conclusions are obtained as follows:the decreased sea ice density caused more Arctic cyclones to generate at positions further west in the Barents Sea and the west of the Kara Sea and then move southeast to East Asia in 2023.Furthermore,the synergistic influences of the outward Arctic cyclones and anomalous signals from middle and low latitudes are discussed.First,the significant northward jump of the Western Pacific Subtropical High(WPSH)provid-ed the favorable condition of large-scale background circulation for summer precipitation in the BTH region in 2023.In addition,the southward intrusion of the Arctic cyclones and the mid-latitude zonal wave trains transported massive cold air to the BTH region.Subsequently,the cold air masses met with the warm moist air carried by the landfall typhoon‘Doksuri’,which generated strong fronts and triggered the extreme precipitation on July 29.However,another severe typhoon,‘Kanu’,generated and moved northward from the tropical Pacific,which caused the further northward shift of the WPSH and the termination of this persistent extreme precipitation on August 1. 展开更多
关键词 extreme summer precipitation Beijing-Tianjin-Hebei region outward arctic cyclone mid-latitude zonal wave train west pacific subtropical high tropical cyclone
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Prevalence of Congenital Heart Disease at Extremely High Altitudes in Tibet and the Establishment of a New Free Treatment Model 被引量:1
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作者 Shuting Chang Guanzhao Zhang +14 位作者 Nengjun Sun Xinpeng Yuan Qingting Wang Lin Zhu Feiyue Zhang Yu Xiu Yang Dong Yonghong Chen Zhanpeng Zhao Xiao Liu Qiang Shao Xiaofeng Xu Anshun Wang Mengjiao Li Bo Li 《Congenital Heart Disease》 SCIE 2022年第6期709-716,共8页
Background:This study aimed to illustrate the prevalence of CHD by screening children in extremely high-altitudeareas(over 4000 m to even 5000 m above sea level)and explore an aid model for early diagnosis and treatme... Background:This study aimed to illustrate the prevalence of CHD by screening children in extremely high-altitudeareas(over 4000 m to even 5000 m above sea level)and explore an aid model for early diagnosis and treatmentfor the Tibetan population.Methods:A total of 2242 students from different schools in Ngamring County,Xigaze City,Tibet from September 2019 to September 2020 were selected for screening.The students were examinedthrough the inquiry of their current medical history and family history,cardiac auscultation and a physicalexamination,in order to screen out the suspected cases of CHD,and then the suspected cases were confirmed bycardiac color ultrasound examinations.After that,positive patients were be transferred to Shandong Province forfree treatment.Results:The prevalence of CHD among children in Ngamring County was 3.70%(83 cases),which is the highest incidence rate ever reported.The most common type of CHD was patent ductus arteriosus(PDA),accounting for 55.42%of the total number of cases screened,followed by atrial septal defect(ASD)andventricular septal defect(VSD),accounting for 28.92%and 12.05%,respectively.The prevalence of CHD in childrenat high altitude was significantly higher than that in children at low altitude.The children with CHD weretransferred to Shandong Province for surgery,the operations were successful and their recoveries went well.Conclusions:The results show that high altitude is closely related to the prevalence of CHD,and the incidencein Ngamring County is much higher than that in previous reports. 展开更多
关键词 TIBET high altitude CHD free treatment model
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A Novel Sensing Imaging Equipment Under Extremely Dim Light for Blast Furnace Burden Surface:Starlight High-Temperature Industrial Endoscope 被引量:1
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作者 Zhipeng Chen Xinyi Wang +3 位作者 Weihua Gui Jilin Zhu Chunhua Yang Zhaohui Jiang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期893-906,共14页
Blast furnace(BF)burden surface contains the most abundant,intuitive and credible smelting information and acquiring high-definition and high-brightness optical images of which is essential to realize precise material... Blast furnace(BF)burden surface contains the most abundant,intuitive and credible smelting information and acquiring high-definition and high-brightness optical images of which is essential to realize precise material charging control,optimize gas flow distribution and improve ironmaking efficiency.It has been challengeable to obtain high-quality optical burden surface images under high-temperature,high-dust,and extremelydim(less than 0.001 Lux)environment.Based on a novel endoscopic sensing detection idea,a reverse telephoto structure starlight imaging system with large field of view and large aperture is designed.Combined with a water-air dual cooling intelligent self-maintenance protection device and the imaging system,a starlight high-temperature industrial endoscope is developed to obtain clear optical burden surface images stably under the harsh environment.Based on an endoscope imaging area model,a material flow trajectory model and a gas-dust coupling distribution model,an optimal installation position and posture configuration method for the endoscope is proposed,which maximizes the effective imaging area and ensures large-area,safe and stable imaging of the device in a confined space.Industrial experiments and applications indicate that the proposed method obtains clear and reliable large-area optical burden surface images and reveals new BF conditions,providing key data support for green iron smelting. 展开更多
关键词 Blast furnace(BF) burden surface extremely dim light industrial endoscope sensing imaging STARLIGHT
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A Nonlinear Multi-Scale Interaction Model for Atmospheric Blocking:A Tool for Exploring the Impact of Changing Climate on Mid-to-High Latitude Weather Extremes 被引量:1
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作者 Dehai LUO Wenqi ZHANG Binhe LUO 《Advances in Atmospheric Sciences》 2025年第10期2018-2035,共18页
A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and... A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and development of the NMI model and then emphasize that the NMI model represents a new tool for identifying the basic physics of how climate change influences mid-to-high latitude weather extremes.The building of the NMI model took place over three main periods.In the 1990s,a nonlinear Schr?dinger(NLS)equation model was presented to describe atmospheric blocking as a wave packet;however,it could not depict the lifetime(10-20 days)of atmospheric blocking.In the 2000s,we proposed an NMI model of atmospheric blocking in a uniform basic flow by making a scale-separation assumption and deriving an eddyforced NLS equation.This model succeeded in describing the life cycle of atmospheric blocking.In the 2020s,the NMI model was extended to include the impact of a changing climate mainly by altering the basic zonal winds and the magnitude of the meridional background potential vorticity gradient(PVy).Model results show that when PVy is smaller,blocking has a weaker dispersion and a stronger nonlinearity,so blocking can be more persistent and have a larger zonal scale and weaker eastward movement,thus favoring stronger weather extremes.However,when PVy is much smaller and below a critical threshold under much stronger winter Arctic warming of global warming,atmospheric blocking becomes locally less persistent and shows a much stronger westward movement,which acts to inhibit local cold extremes.Such a case does not happen in summer under global warming because PVy fails to fall below the critical threshold.Thus,our theory indicates that global warming can render summer-blocking anticyclones and mid-to-high latitude heatwaves more persistent,intense,and widespread. 展开更多
关键词 nonlinear Schrödinger equation nonlinear multi-scale interaction model of atmospheric blocking meridional background potential vorticity gradient climate change mid-to-high latitude weather extremes
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Natural gas density under extremely high pressure and high temperature: Comparison of molecular dynamics simulation with corresponding state model 被引量:1
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作者 Luchao Jin Yongming He +3 位作者 Guobing Zhou Qiuhao Chang Liangliang Huang Xingru Wu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第3期2-9,共8页
This work applied molecular dynamics(MD)simulation to calculate densities of natural gas mixtures at extremely high pressure(>138 MPa)and high temperature(>200℃)conditions(x HPHT)to bridge the knowledge and tec... This work applied molecular dynamics(MD)simulation to calculate densities of natural gas mixtures at extremely high pressure(>138 MPa)and high temperature(>200℃)conditions(x HPHT)to bridge the knowledge and technical gaps between experiments and classical theories.The experimental data are scarce at these conditions which are also out of assumptions for classical predictive correlations,such as the Dranchuk&Abou-Kassem(DAK)equation of state(EOS).Force fields of natural gas components were carefully chosen from literatures and the simulation results are validated with experimental data.The largest relative error is 2.67%for pure hydrocarbons,2.99%for C1/C3 mixture,7.85%for C1/C4 mixture,and 8.47%for pure H2S.These satisfactory predictions demonstrate that the MD simulation approach is reliable to predict natural-and acid-gases thermodynamic properties.The validated model is further used to generate data for the study of the EOS with pressure up to 276 MPa and temperature up to 573 K.Our results also reveal that the Dranchuk&Abou-Kassem(DAK)EOS is capable of predicting natural gas compressibility to a satisfactory accuracy at x HPHT conditions,which extends the confidence range of the DAK EOS. 展开更多
关键词 high-pressure high temperature Z-factor Molecular dynamics simulation Natural gas density CORRELATIONS
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Highly Differentiated Target Detection under Extremely Low-Light Conditions Based on Improved YOLOX Model
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作者 Haijian Shao Suqin Lei +2 位作者 Chenxu Yan Xing Deng Yunsong Qi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1507-1537,共31页
This paper expounds upon a novel target detection methodology distinguished by its elevated discriminatory efficacy,specifically tailored for environments characterized by markedly low luminance levels.Conventional me... This paper expounds upon a novel target detection methodology distinguished by its elevated discriminatory efficacy,specifically tailored for environments characterized by markedly low luminance levels.Conventional methodologies struggle with the challenges posed by luminosity fluctuations,especially in settings characterized by diminished radiance,further exacerbated by the utilization of suboptimal imaging instrumentation.The envisioned approach mandates a departure from the conventional YOLOX model,which exhibits inadequacies in mitigating these challenges.To enhance the efficacy of this approach in low-light conditions,the dehazing algorithm undergoes refinement,effecting a discerning regulation of the transmission rate at the pixel level,reducing it to values below 0.5,thereby resulting in an augmentation of image contrast.Subsequently,the coiflet wavelet transform is employed to discern and isolate high-discriminatory attributes by dismantling low-frequency image attributes and extracting high-frequency attributes across divergent axes.The utilization of CycleGAN serves to elevate the features of low-light imagery across an array of stylistic variances.Advanced computational methodologies are then employed to amalgamate and conflate intricate attributes originating from images characterized by distinct stylistic orientations,thereby augmenting the model’s erudition potential.Empirical validation conducted on the PASCAL VOC and MS COCO 2017 datasets substantiates pronounced advancements.The refined low-light enhancement algorithm yields a discernible 5.9%augmentation in the target detection evaluation index when compared to the original imagery.Mean Average Precision(mAP)undergoes enhancements of 9.45%and 0.052%in low-light visual renditions relative to conventional YOLOX outcomes.The envisaged approach presents a myriad of advantages over prevailing benchmark methodologies in the realm of target detection within environments marked by an acute scarcity of luminosity. 展开更多
关键词 Target detection extremely low-light wavelet transformation highly differentiated features YOLOX
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The influence of low-intensity electromagnetic radiation of extremely high frequency upon experimental focal epileptic syndrome 被引量:1
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作者 V.N.Zaporozhan L.S.Godlevsky S.L.Tsevelev 《中国现代医学杂志》 CAS CSCD 北大核心 2011年第27期3331-3334,共4页
The aim of the work was confined to the investigation of the epileptic activity dynamics under conditions of extremely high frequency electromagnetic waves(EHF) radiation(7.1 mm,0.1 mW/cm2) upon focal epileptic activi... The aim of the work was confined to the investigation of the epileptic activity dynamics under conditions of extremely high frequency electromagnetic waves(EHF) radiation(7.1 mm,0.1 mW/cm2) upon focal epileptic activity,which was penicillin-induced(10 000 IU/ml) in frontal zone of the brain cortex in myorelaxed and artificially ventilated rats under acute experimental condition.It was established that preliminarily performed hypogeomagnetic period(3.0 h) with the inductivity of geomagnetic field reduction not less than by 100 times caused the intensification of antiepileptic effects of EHF(15.0 min of exposition).It was pronounced in the form of decrease of foci intensity and significant reduction of life-span of foci-up to 115.3±13.4 minutes,which was both significant when compared with separate effects of hypogeomagnetic influence(187.3±12.5 min) and EHF(15.0 minutes of exposition) effect(164.2±12.5 minutes)(P <0.05). 展开更多
关键词 癫痫症 临床 治疗 疗效
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Extremely large magnetoresistance in single-crystalline ZrBi_(2)
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作者 Cundong Li Binbin Ruan +9 位作者 Qingxin Dong Jianli Bai Libo Zhang Qiaoyu Liu Jingwen Cheng Pinyu Liu Yu Huang Yingrui Sun Zhian Ren Genfu Chen 《Chinese Physics B》 2025年第9期552-558,共7页
Magnetoresistance(MR)is a pivotal transport phenomenon within the realm of condensed matter physics.In recent years,materials exhibiting extremely large unsaturated magnetoresistance(XMR),which are often potential top... Magnetoresistance(MR)is a pivotal transport phenomenon within the realm of condensed matter physics.In recent years,materials exhibiting extremely large unsaturated magnetoresistance(XMR),which are often potential topological materials,have garnered significant attention.In this study,we synthesized single crystals of ZrBi_(2) and performed electrical and specific heat measurements on them.The resistivity of ZrBi_(2) displays metallic behavior with a high residual resistance ratio.Notably,the MR of ZrBi_(2) reaches approximately 2.0×10^(3)%at 2 K and 16 T without saturation.Weak Shubnikov-de Haas oscillations with two frequencies were observed above 13.5 T,which correspond to 237 T and 663 T.Hall effect fitting yields nearly equal concentrations of electron and hole carriers with concentrations of approximately 10^(21)cm^(-3)and mobilities of approximately 5000 cm^(2)·V^(-1)·s^(-1)at 2 K.The XMR could be attributed to the electron-hole compensation with high mobility. 展开更多
关键词 extremely large magnetoresistance SdH oscillation electron-hole compensation
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Refinement and strengthening mechanism of Mg−Zn−Cu−Zr−Ca alloy solidified under extremely high pressure 被引量:4
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作者 Xiao-ping LIN Yang KUO +4 位作者 Lin WANG Jie YE Chong ZHANG Li WANG Kun-yu GUO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第6期1587-1598,共12页
Mg−Zn−Cu−Zr−Ca samples were solidified under high pressures of 2-6 GPa.Scanning electron microscopy and electron backscatter diffraction were used to study the distribution of Ca in the microstructure and its effect o... Mg−Zn−Cu−Zr−Ca samples were solidified under high pressures of 2-6 GPa.Scanning electron microscopy and electron backscatter diffraction were used to study the distribution of Ca in the microstructure and its effect on the solidification structure.The mechanical properties of the samples were investigated through compression tests.The results show that Ca is mostly dissolved in the matrix and the Mg_(2)Ca phase is formed under high pressure,but it is mainly segregated among dendrites under atmospheric pressure.The Mg_(2)Ca particles are effective heterogeneous nuclei ofα-Mg crystals,which significantly increases the number of crystal nuclei and refines the solidification structure of the alloy,with the grain size reduced to 22μm at 6 GPa.As no Ca segregating among the dendrites exists,more Zn is dissolved in the matrix.Consequently,the intergranular second phase changes from MgZn with a higher Zn/Mg ratio to Mg7Zn3 with a lower Zn/Mg ratio.The volume fraction of the intergranular second phase also increases to 22%.Owing to the combined strengthening of grain refinement,solid solution,and dispersion,the compression strength of the Mg-Zn-Cu-Zr-Ca alloy solidified under 6 GPa is up to 520 MPa. 展开更多
关键词 high pressure solidification Mg−Zn−Cu−Zr−Ca alloy Mg_(2)Ca particle solution strengthening grain refinement strengthening
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Extreme removal of fine inclusions from 304 stainless steel via high-temperature supergravity fields
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作者 Shuai Zhang Lei Guo Zhancheng Guo 《International Journal of Minerals,Metallurgy and Materials》 2025年第10期2483-2494,共12页
The extreme removal of SiO2 and MnO inclusions in 304 stainless steel in supergravity fields was investigated using an inhouse high-temperature supergravity equipment.The influences of the gravity coefficient and sepa... The extreme removal of SiO2 and MnO inclusions in 304 stainless steel in supergravity fields was investigated using an inhouse high-temperature supergravity equipment.The influences of the gravity coefficient and separation time on the removal efficiency of the inclusions were studied.After supergravity treatment,the inclusions migrated to the top of the sample and formed large aggregates.Meanwhile,the lower part of the sample was purified considerably and appeared significantly cleaner than the raw material.At the gravity coefficient of 500 and separation time of 600 s,the total oxygen content at the bottom of the sample(position E)decreased from 240 to 28 ppm.This corresponded to a total oxygen removal rate of 88.33%.The volume fraction and number density of inclusions exhibited a gradient distribution along the supergravity direction,with values of 8.5%and 106 mm^(-2) at the top of the sample(position A)and 0.06%and 22 mm^(-2) at its bottom. 展开更多
关键词 304 stainless steel INCLUSIONS supergravity fields separation extreme removal
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Endovascular electrocoagulation for treating a blister-like microaneurysm with an extremely narrow neck:A case report
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作者 Zhi-Yuan Zhang Xian-Yi Zhang +3 位作者 Guo-Zhang Lu Shi-Lei Wang Ji-Heng Hao Li-Yong Zhang 《World Journal of Clinical Cases》 2025年第32期110-115,共6页
BACKGROUND Intracranial blister-like microaneurysms are an extremely rare disease.Rupture of intracranial aneurysms can lead to subarachnoid hemorrhage(SAH).Patients with SAH may experience severe neurological symptom... BACKGROUND Intracranial blister-like microaneurysms are an extremely rare disease.Rupture of intracranial aneurysms can lead to subarachnoid hemorrhage(SAH).Patients with SAH may experience severe neurological symptoms,including severe headache,nausea,vomiting,transient or persistent loss of consciousness,limb weakness,and blurred vision.Ruptured aneurysms should be surgically treated as soon as possible.Intravascular electrocoagulation is becoming a promising treatment method for intracranial blister-like microaneurysms.The short-term follow-up results demonstrated that this method is safe and effective.This article presents a case of endovascular electrocoagulation for the treatment of a blisterlike microaneurysm.CASE SUMMARY This article reports the case of 71-year-old female patient with an intracranial aneurysm.The patient experienced a sudden headache with vomiting for 3 hours.Brain computed tomography(CT)scan showed a subarachnoid hemorrhage.She was diagnosed with rupture of an aneurysm and subarachnoid hemorrhage.The aneurysm was located in the choroidal segment of the right internal carotid artery.The size of the aneurysm was 2.00 mm×1.80 mm×1.97 mm,and the neck of the aneurysm was less than 0.5 mm wide.We successfully treated this aneurysm with endovascular electrocoagulation,and the patient was safely returned to the ward and discharged after subsequent supportive treatment.CT angiography reexamination 3 months after surgery revealed no contrast agent extravasation in the original lesion,with a good prognosis.CONCLUSION Endovascular electrocoagulation is an effective and safe method for the treatment of intracranial blister-like microaneurysms. 展开更多
关键词 MICROANEURYSM Blister-like Endovascular electrocoagulation extremely narrow neck Case report
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