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基于Group-Res2Block的智能合成语音说话人确认方法
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作者 李菲 苏兆品 +2 位作者 王年松 杨波 张国富 《应用科学学报》 CAS CSCD 北大核心 2024年第4期709-722,共14页
针对现有说话人确认任务基于自然语音条件下并不适用于智能合成语音的问题,提出一种基于Group-Res2Block的智能合成语音说话人确认方法。首先,设计了Group-Res2Block结构,在Res2Block的基础上将当前分组与相邻前后分组进行合并形成新的... 针对现有说话人确认任务基于自然语音条件下并不适用于智能合成语音的问题,提出一种基于Group-Res2Block的智能合成语音说话人确认方法。首先,设计了Group-Res2Block结构,在Res2Block的基础上将当前分组与相邻前后分组进行合并形成新的分组,以增强说话人局部特征的上下文联系;其次,设计了并行结构的多尺度通道注意力特征融合机制,利用不同大小卷积核实现同一层级的特征在通道维度的特征选择,以获取更具表现力的说话人特征,避免信息冗余;最后,设计了串行结构的多尺度层注意力特征融合机制,构建层结构,将深浅层特征整体进行融合并赋予不同权重,以获取最优的特征表达。为验证所提出特征提取网络的有效性,构建了中英文两种智能合成语音数据集进行消融实验和对比实验。结果表明本文方法在该任务的评价指标精确度(accuracy,ACC)、等错误率(equal error rate,EER)和最小检测代价函数(minimum detection cost function,minDCF)上是最优的。此外,通过对模型泛化性能进行测试,验证了本文方法对未知智能语音算法的适用性。 展开更多
关键词 说话人确认 智能合成语音 Group-Res2block深度神经网络 多尺度特征 注意力机制
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Metamorphic P-T conditions and ages of garnet-biotite schists in the Dahongshan Group from the southwestern Yangtze Block
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作者 Jun-xiao Ma Guang-shu Yang +5 位作者 Yong-feng Yan Xiao-Fei Xu Yun-hua Ren Hui Zhao Xiao-jun Zheng Yuan Qin 《Acta Geochimica》 EI CAS CSCD 2024年第4期707-718,共12页
The Dahongshan Group,situated at the southwestern margin of the Yangtze Block,represents a geological unit characterized by relatively high-grade metamorphism in the region.This paper investigates the garnet-biotite s... The Dahongshan Group,situated at the southwestern margin of the Yangtze Block,represents a geological unit characterized by relatively high-grade metamorphism in the region.This paper investigates the garnet-biotite schist from the Laochanghe Formation of the Dahongshan Group,employing an integrated approach that includes petrological analysis,phase equilibrium modeling,and zircon U-Pb dating.The schist is mainly composed of garnet,biotite,plagioclase,quartz,rutile,and ilmenite.Phase equilibrium modeling revealed the peak metamorphic conditions of 8-9 kbar and 635-675°C.By further integrating the prograde metamorphic profile of garnet and geothermobarometric results,a clockwise P-T metamorphic evolution path is constructed,which includes an increase in temperature and pressure during the prograde stage.LA-ICP-MS zircon U-Pb dating and zircon Ti thermometry constrains the post-peak metamorphic age of 831.2±7.2 Ma.Integrated with previously reported results,it is revealed that the southwestern margin of the Yangtze Block experienced a large-scale regional metamorphism during the Neoproterozoic(890-750 Ma),which is related to the collisional orogenic process.This may be associated with the late-stage assembly of the Rodinia supercontinent or with local compression and subduction processes during the breakup of the Rodinia supercontinent. 展开更多
关键词 Southwestern Yangtze block Dahongshan Group Phase equilibrium modeling Zircon U-Pb dating Neoproterozoic metamorphism
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Enhancing postoperative pain control by surgically-initiated rectus sheath block in abdominal aortic aneurysm open repair: A case report
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作者 Kuan-Hua Chen Ming-Yuan Kang +2 位作者 Yi-Ting Chang Sheng-Yang Huang Yung-Szu Wu 《World Journal of Clinical Cases》 SCIE 2025年第6期41-47,共7页
BACKGROUND Abdominal aortic aneurysm(AAA)repair often involves significant postoperative pain,traditionally managed with systemic opioids,which can cause undesirable side effects.This case report explores the novel us... BACKGROUND Abdominal aortic aneurysm(AAA)repair often involves significant postoperative pain,traditionally managed with systemic opioids,which can cause undesirable side effects.This case report explores the novel use of a surgically-initiated rectus sheath block with a catheter-over-needle assembly for pain management in AAA repair.CASE SUMMARY A 67-year-old female with hypertension and previous aortic dissection underwent elective open repair of an infrarenal AAA,which had grown from 3.4 cm to 4.3 cm over 14 months.A rectus sheath block was initiated surgically for postoperative pain control.The patient reported low pain scores and did not require systemic intravenous opioids,enabling early ambulation and discharge on postoperative day seven without complications.By preventing complications of systemic opi-oids,the method indicating a promising direction for postoperative pain management in major vascular surgeries.CONCLUSION Surgically-initiated rectus sheath block as a valuable tool for managing postoperative pain in AAA repair. 展开更多
关键词 Abdominal aortic aneurysm Postoperative pain management Rectus sheath block Surgical anesthesia Opioid-sparing techniques Case report
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Lie Triple Derivations of the Lie Algebra of Dominant Block Upper Triangular Matrices
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作者 Prakash Ghimire Huajun Huang 《Algebra Colloquium》 SCIE CSCD 2018年第3期475-492,共18页
Let N be the Lie algebra of all n x n dominant block upper triangular matrices over a field F. In this paper, we explicitly describe all Lie triple derivations of N when char(F) ≠ 2. As an application, we character... Let N be the Lie algebra of all n x n dominant block upper triangular matrices over a field F. In this paper, we explicitly describe all Lie triple derivations of N when char(F) ≠ 2. As an application, we characterize Lie derivations of N when char(F) ≠ 2. 展开更多
关键词 Lie triple derivation block upper triangular matrix Lie algebra
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Review of Infrared signature suppression systems using optical blocking method 被引量:12
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作者 Nidhi Baranwal Shripad P. Mahulikar 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第3期432-439,共8页
With rapid advancements in Infra-Red (IR) detection techniques, the range from where the IR-guided missiles are able to lock the target aircraft has increased. To avoid the detection and tracking by modern IR-guided m... With rapid advancements in Infra-Red (IR) detection techniques, the range from where the IR-guided missiles are able to lock the target aircraft has increased. To avoid the detection and tracking by modern IR-guided missiles, the aircraft and helicopters also demand progress in its stealth techniques. Hence, study of Infra-Red Signature Suppression (IRSS) systems in aircraft and helicopters has become vital even in design stage. Optical blocking (masking) is one of the effective IRSS techniques used to block the Line- Of-Sight (LOS) of the hot engine parts of the exhaust geometry. This paper reviews the various patents on IR signature suppression systems based on the optical blocking method or a combination of IRSS techniques. The performance penalties generated due to installation of various IRSS methods in aircraft and helicopters are also discussed. 展开更多
关键词 IR SIGNATURE SupPRESSION OPTICAL blockING Performance PENALTY IR SIGNATURE level Engine back-pressure
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Structure of the Upper Mantle and Transition Zone Beneath the South China Block Imaged by Finite Frequency Tomography 被引量:9
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作者 SUN Ya LIU Jianxin +3 位作者 TANG Youcai CHEN Jiawei ZHOU Keping CHEN Bo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第5期1637-1652,共16页
We applied the finite frequency tomography method to S wave data recorded by 350 broadband stations beneath the South China Block(SCB) and its surroundings from earthquakes occurring between July 2007 and July 2010,... We applied the finite frequency tomography method to S wave data recorded by 350 broadband stations beneath the South China Block(SCB) and its surroundings from earthquakes occurring between July 2007 and July 2010,to better understand upper mantle deformation.Differential travel-times in the pair of stations with appropriate weighting for each station are used in the inversion.Our results are consistent with previous tomography that show a high velocity anomaly beneath the Sichuan basin and a high velocity anomaly in the transition zone beneath the Yangtze Craton.However,the resolution of mantle heterogeneity provides new insight into the tectonic framework of subduction of Burmese lithosphere in the west part of the study region and subduction of oceanic lithosphere in the east.In the subduction realm,west of 107°E,a significant fast S-wave anomaly is located on the southeast of Sichuan Basin.East of 107°E,and two narrow and discontinuous fast S-wave anomalies occur at a depth of 400-600 km beneath the middle of the South China block overlain by the pronounced low S-wave anomalies at a depth of 100 and 400 km.If the fast anomalies located in the mantle transition zone represent stagnant slabs,their fragmented nature may suggest that they could be produced by different episodes of subduction beneath western Pacific island and the above slow velocity anomaly may associated with the back-arc regions of ongoing subduction.In addition,tomography also reveals an anomalously high S-wave velocity continental root extends eastward to a depth 400 km beneath the eastern Sichuan Basin.This anomaly may be related to eastern extrusion of Indian lithosphere associated with the collision of India and Eurasia.Moreover,our results also show large slow anomalies beneath the Red River fault region connected to deeper anomalies beneath the South China Fold Belt and South China Sea.AH these observations are consistent with the scenario that the South China block has been built by both of subduction of Paleopacific plate and eastward subduction of Burma microplate. 展开更多
关键词 finite frequency tomography South China block station pairs SUBDUCTION Paleo-pacific plate
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Reservoir Characteristics and Preservation Conditions of Longmaxi Shale in the Upper Yangtze Block, South China 被引量:8
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作者 RAN Bo LIU Shugen +9 位作者 Luba JANSA SUN Wei YANG Di WANG Shiyu YE Yuehao Christopher XIAO ZHANHG Jian ZHAI Cangbo LUO Chao ZHANG Changjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第6期2182-2205,共24页
The Upper Ordovician-Lower Silurian Longmaxi Shale in the Upper Yangtze block represents one of the most important shale gas plays in China. The shale composition, porosity, organic thermal maturity, and methane sorpt... The Upper Ordovician-Lower Silurian Longmaxi Shale in the Upper Yangtze block represents one of the most important shale gas plays in China. The shale composition, porosity, organic thermal maturity, and methane sorption were investigated at the Qilongcun section in the Dingshan area, southeastern Sichuan Basin. The results show that the Upper Ordovician-Lower Silurian Longmaxi Shale contains: (1) sapropelic I organic matter; (2) a 40-m thick bedded sequence where total organic carbon (TOC) content is 〉 2%; (3) a 30-m thick layer at the base of the Longmaxi Shale with a brittle mineral content higher than 50%; and (4) a mean methane adsorption capacity of 1.80 cm3/g (7 MPa pressure). A positive correlation between TOC and sorbed gas indicates that organic matter content exerts an important control on methane storage capacity. Based on the analysis of the shale reservoir characteristics, the lower member of the Longmaxi Shale can thus be considered a favorable stratum for shale gas exploration and exploitation. It has similar reservoir characteristics with the Longmaxi Shale in the Jiaoshiba area tested with a high-yield industrial gas flow. However, based on tectonic analysis, differences in the level of industrial gas flow between the low-yield study area and the high-yield Jiaoshiba area may result from different tectonic preservation conditions. Evidence from these studies indicates the shale gas potential of the Longmaxi Shale is constrained by the reservoir and preservation conditions. 展开更多
关键词 Longmaxi Shale shale gas RESERVOIR upper Yangtze block preservation condition
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PRESENT LANDFORMS, ACTIVE TECTONIC ZONES, DEEP STRUCTURES AND UPLIFT MECHANISMS OF THE LONGSHOUSHAN BLOCK ON THE NORTHERN MARGIN OF THE QINGHAI—TIBET PLATEAU 被引量:4
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作者 Dong Zhiping, Zhang Jie (Lanzhou Institute of Seismology, CSB, Lanzhou 730000, China) 《地学前缘》 EI CAS CSCD 2000年第S1期258-259,共2页
Located in the northern margin of the Qinghai—Tibet Plateau, the Longshoushan Mt. is a small block between Qinghai—Tibet Landmass and Alashan Landmass.Traditional tectonic viewpoint does not consider that the Longsh... Located in the northern margin of the Qinghai—Tibet Plateau, the Longshoushan Mt. is a small block between Qinghai—Tibet Landmass and Alashan Landmass.Traditional tectonic viewpoint does not consider that the Longshoushan Mt. is a single tectonic block. It is quite evident that there is only a hazy idea about the Longshoushan block. Though there is a very complex tectonic region between Qinghai—Tibet Landmass and Alashan Landmass, the Longshoushan block in the region shows unique tectonic landforms, deep structures and uplift mechanisms. Researching into the relationship between the Longshoushan block and the Qinghai—Tibet and Alashan Landmasses will contribute to the realization of boundary and orogenic belt on the northern margin of the Qinghai—Tibet block. It is a very important scientific subject.The Longshoushan Mt., longer than 150km in NWW direction and wider than 10km, is located on the northern side of Hexi corridor(100 5°~102 5°E,38 5°~39 3°N). It extends from the northwest of Zhangye to Hexibu, and from the south of Chaoshui basin to the north of Minle basin. From west to east, there are the highest peak, Dongdashan Mt.(3616m), the second peak, Dufengding(2937m) and Qianshan peak(2827m), height of the mountains is getting lower and lower, mean height above sea level is over 2000m, and relative height difference is about 1000m. The Longshoushan Mt. provides a natural defence for stopping the southward migration of sandstorm in the Hexi corridor, and forms a topographic step zone from the Alashan Plateau to the Qinghai—Tibet Plateau. In the Longshoushan area, developed landforms, such as planation surface, table\|land, terrace land, are general characters of all geomorphic units. It is shown that the Longshoushan Mt. is a intermittently uplifted block. An astonishingly similar of geometric patterns of Taohualashan Mt. and Hongshihu basin is very interesting natural landscape in the area. It is suggested that Taohualashan Mt. broke away from Hongshihu Basin in secular tectonic movement. The viewpoint is supported by major formation, lithofacies, limitation and style of active faulting. The Longshoushan block consists of two major active fault zones (the northern Longshoushan fault zone and the southern Longshoushan fault zone), the active Pingshanhu—Hongshihu fault basin belt and Taohualashan—Xieposhan tectonic uplift belt. In addition, there are the NNW\|trending West Polamading fault, NWW\|trending Maohudong fault trough, NNE\|trending Daxiahe rift valley and others on the block. the activity and formation style of these structures indicate that the block is acted not only by compressive stress, but also by tensile stress. The northern Longshoushan and southern Longshoushan fault zones are closely related to formation and evolution of the Longshoushan block, the two zones are active fault zones since late Pleistocene and boundary fault zones of the block. The genesis and activity style of the Pingshanhu\|Hongshihu basin are similar to the continental rift, which may be due to the mantle uplift. 展开更多
关键词 Qinghai—Tibet Plateau Longshoushan block Hexi CORRIDOR mantle upLIFT active STRUCTURE deep STRUCTURE block upLIFT Longshoushan Mt.
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Experimental investigation on friction and squeezing of roof structure key blocks corner upon long-wall face 被引量:7
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作者 QingxiangHuang 《Journal of University of Science and Technology Beijing》 CSCD 2005年第2期102-105,共4页
The coefficients of friction and squeezing of the key blocks comer in the roof structure of underground coalface are key factors to roof structure stability quantitative analysis. In this paper, through the special t... The coefficients of friction and squeezing of the key blocks comer in the roof structure of underground coalface are key factors to roof structure stability quantitative analysis. In this paper, through the special test of three-type corner friction and squeez- ing of real rock specimens, and physical simulation test on the roof key blocks of roof structure as well as the finite element calcula- tion of the corner stress distribution and failure mechanism, the characteristics of friction and squeezing of the roof key blocks comer are revealed. It is found that the friction angle of the roof key blocks corner is the residual friction angle, and the frictional angle of the roof key blocks is 22-32° (average 27°), so the friction coefficient is determined as 0.5. It also found the squeezing strength is less than the uniaxial strength, and the squeezing coefficient of the roof blocks corner is determined as 0.4. Based on the results, the ground control theory can be updated from qualitative analysis to quantitative analysis. 展开更多
关键词 roof structure key blocks FRICTION SQUEEZING blocks corner
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Depositional Age, Provenance Characteristics and Tectonic Setting of the Ailaoshan Group in the Southwestern South China Block 被引量:4
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作者 JI Lei LIU Fulai +1 位作者 WANG Fang TIAN Zhonghua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第6期1687-1710,共24页
The depositional and metamorphic ages and provenances of the Ailaoshan(ALS) Group in the Ailaoshan-Red River(ALS-RR) shear zone, southwestern South China Block(SCB), were investigated to constrain the tectonic history... The depositional and metamorphic ages and provenances of the Ailaoshan(ALS) Group in the Ailaoshan-Red River(ALS-RR) shear zone, southwestern South China Block(SCB), were investigated to constrain the tectonic history of the southwestern SCB. In this study, we use petrology, geochemical analysis, zircon cathodoluminescence imaging and UPb geochronology to analyse samples of quartzite, garnet-bearing two-mica schist and metapelite. The age spectra of detrital zircon grains from these metasediments show two dominant age peaks at 550–424 Ma and 876–730 Ma and two subordinate peaks at 970–955 Ma and ~2450 Ma. The youngest peak, corresponding to the early Palaeozoic, accounts for more than 20% of the total dates and constrains the deposition of the ALS Group to the Palaeozoic rather than the Palaeoproterozoic as traditionally thought. Moreover, two peaks of metamorphic ages corresponding to the Permo-Triassic and Cenozoic were also identified, and these ages document the tectonothermal events associated with the Indosinian collision between the Indochina Block and the SCB and the Himalayan collision between the Indian and Asian plates. Geochemical data suggest that the provenances of the ALS Group were dominated by continental arc and recycled metasedimentary rocks. The comparison of probability density distribution plots of the detrital zircon U-Pb age data indicates that the Neoproterozoic detritus in the ALS Group was probably derived from the arc-related Neoproterozoic intrusive bodies in the northwestern and southwestern SCB. Furthermore, the early Palaeozoic detritus might have been sourced from eroded early Palaeozoic strata and magmatic plutons in Cathaysia and volcanic rocks in the western Indochina Block. 展开更多
关键词 detrital zircon depositional age PROVENANCE Ailaoshan Group South China block
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Sedimentary microtopography in sequence stratigraphic framework of Upper Ordovician and its control over penecontemporaneous karstification,No.I slope break,Tazhong,Tarim block 被引量:5
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作者 张云峰 王振宇 +2 位作者 屈海洲 罗春树 李越 《Journal of Central South University》 SCIE EI CAS 2014年第2期735-744,共10页
In order to reveal the relationship between the penecontemporaneous karstification and sedimentary microtopography in sequence stratigraphy,the sequence stratigraphic framework of Lianglitage formation in Upper Ordovi... In order to reveal the relationship between the penecontemporaneous karstification and sedimentary microtopography in sequence stratigraphy,the sequence stratigraphic framework of Lianglitage formation in Upper Ordovician is studied according to the well drilling,logging,geophysical data,detailed observations of core and the paleontology.The Lianglitage formation belongs to the sequence Ⅳ of Ordovician.The second member of Lianglitage formation is prograde sedimentation in highstand systems tract,and is favorable for developing reef flat.The development scale and thickness of reef flat are controlled by the variation of secondary sea level.The types and characteristics of karst in the highstand systems tract show that the late highstand systems tract is dissolved and cemented by the meteoric fresh water and mixed water.Penecontemporaneous karstification is developed at the top of parasequence and high place of geomorphology.Atmospheric diagenetic lens is formed.The developing regulations and controlling factors of penecontemporaneous karstification can provide new clues to the prediction and exploration of favorable reservoir in this area. 展开更多
关键词 sequence stratigraphy sedimentary microtopography penecontemporaneous karstification upper Ordovician Tazhong I slope break Tarim block
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Numerical Study of Ural Blocking High's Effect Upon Asian Summer Monsoon Circulation and East China Flood and Drought 被引量:4
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作者 何金海 周学鸣 叶荣生 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1995年第3期361-370,共10页
In terms of Kuo-Qian pesigma incorporated coordinate five-level primitive equation spheric band (70°N-30°S)model with the Ural high's effect introduced into it as initial and boundary conditions, study i... In terms of Kuo-Qian pesigma incorporated coordinate five-level primitive equation spheric band (70°N-30°S)model with the Ural high's effect introduced into it as initial and boundary conditions, study is made of the high's influence on Asian summer monsoon circulation and dryness / wetness of eastern China based on case contrast andcontrol experiments. Rusults show that as an excitation source, the blocking high produces a SE-NW stationarywavetrain with its upper-air atnicyclonic divergent circulation oust over a lower-level trough zone) precisely over themiddle to lower reaches of the Changjiang River, enhancing East Asian westerly jet, a situation that contributes toPerturbation growth, causing an additional secondary meridional circulation at the jet entrance, which intensifies theupdraft in the monsoon area. As such, the high's presence and its excited steady wavetrain represent the large-scalekey factors and acting mechanisms for the rainstorm over the Changjiang-Huaihe River catchment in the easternpart of the land. 展开更多
关键词 Ural blocking high Asian summer monsoon circulation East China flood and drought
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Ultrasound-guided,direct suprainguinal injection for fascia iliaca block for total hip arthroplasty:A retrospective study 被引量:4
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作者 Ya-Li Wang Yun-Qing Liu +6 位作者 Hua Ni Xin-Lei Zhang Li Ding Fei Tong Hong-Ye Chen Xin-Hua Zhang Ming-Jian Kong 《World Journal of Clinical Cases》 SCIE 2021年第15期3567-3575,共9页
BACKGROUND Peripheral regional block combined with general anesthesia might be a preferable anesthetic regimen for elderly patients undergoing total hip arthroplasty.AIM To investigate whether ultrasound-guided,direct... BACKGROUND Peripheral regional block combined with general anesthesia might be a preferable anesthetic regimen for elderly patients undergoing total hip arthroplasty.AIM To investigate whether ultrasound-guided,direct suprainguinal injection for fascia iliaca block accelerated recovery after general anesthesia and relieved postoperative pain after total hip arthroplasty.METHODS Patients who underwent total hip arthroplasty under general anesthesia in 2015 or 2019 at The Second Affiliated Hospital of Xuzhou Medical University were retrospectively analyzed.The patients were grouped based on whether preoperative suprainguinal fascia iliaca block was performed or not.The time to tracheal extubation and time spent in the post-anesthesia care unit(PACU),intraoperative remifentanil dosage,fentanyl consumption in the PACU,postoperative cumulative fentanyl consumption within 48 h after operation,visual analogue scale at rest and during movement on the first and second days after surgery,and adverse reactions were compared.RESULTS Thirty-one elderly patients who underwent total hip arthroplasty were included in the study(block group,n=16;no-block group,n=15).The visual analog scale scores at rest and during movement on the first and second days were significantly lower in the block group than in the no-block group(all P<0.05).Compared with the no-block group,the intraoperative remifentanil dosage was lower,the time to tracheal extubation and the time spent in the PACU were shorter in the block group(all P<0.01).Fentanyl consumption in the PACU and postoperative cumulative fentanyl consumption in 48 h after operation were lower in the block group(all P<0.01).The incidence of dizziness was higher in the no-block group than in the block group(P=0.037).CONCLUSION Ultrasound-guided,direct suprainguinal injection for fascia iliaca block led to faster recovery after general anesthesia and early postoperative pain relief in elderly patients undergoing total hip arthroplasty. 展开更多
关键词 Suprainguinal fascia iliaca block Elderly patients Total hip arthroplasty General anesthesia recovery Postoperative pain
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Segmentations of active normal dip-slip faults around Ordos block according to their surface ruptures in historical strong earthquakes 被引量:2
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作者 沈德福 江娃利 +1 位作者 肖振敏 谢新生 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2000年第5期552-562,共11页
From the results of researches of active faults in resent years, a correlation analysis between segments of the faults according to surface ruptures in nine historical strong earthquakes occurring in downfaulted syste... From the results of researches of active faults in resent years, a correlation analysis between segments of the faults according to surface ruptures in nine historical strong earthquakes occurring in downfaulted system and active structures around Ordos block is conducted in paper. The result shows that there is a good correlation between them, except few individual data that have more uncertain parameters. It shows that intensity and segments of surface ruptures in these strong earthquakes are intrinsically related with the active structures. These strong earthquakes produced stable and unstable rupture boundaries of characteristic-earthquake type and successive occurrence of strong earthquakes on the different boundary faults in the same tectonic unit. 展开更多
关键词 surface rupture fault segmentation historical strong earthquakes normal dip-slip faults Ordos block
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Does the Luangwa Hippo Population Size and Density Distribution Vary between Upper and Lower Study Blocks? What Are the Management Implications of Such Distribution Pattern? 被引量:2
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作者 Chansa Chomba Twakundine Simpamba +1 位作者 George Kampamba Vincent Nyirenda 《Open Journal of Ecology》 2014年第5期262-280,共19页
The pattern of population distribution of the common hippopotamus was examined along the 165 km stretch of the Luangwa River in eastern Zambia. The study area was divided between the upper (A-D) and lower (E-H) study ... The pattern of population distribution of the common hippopotamus was examined along the 165 km stretch of the Luangwa River in eastern Zambia. The study area was divided between the upper (A-D) and lower (E-H) study blocks. Population data are collected between 1976-2008 and this study 2009-2012 showed a significant difference in the pattern of density distribution between upper and lower study blocks. Upper blocks had higher density of 41/km than lower blocks 29/km. Length of study blocks was discounted as density was used to determine distribution pattern. Results obtained suggest that primary production in each study block as influenced by river geomorphologic features such as river bends and confluences characterized higher hippopotamus density in the upper blocks. Further research is required to investigate other factors that may have interplayed with food (above ground grass biomass) and river meander features to separate upper and lower blocks. 展开更多
关键词 Common HIPPOPOTAMUS Pattern Density upPER blockS LOWER blockS
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Geochronology and Tectonic Implications of Diabase Intruded Into Xiangshan Group in the Southeastern Alxa Block, NW China 被引量:4
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作者 ZHANG Yiping CHEN Xuanhua ZHANG Jin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期88-91,共4页
The southeastern Alxa Block(i.e.,the Hexi Corridor)is a tectonic junction between the North China Block(NCB)to the east,the Alxa Block to the north,and the western Qinling–North Qilian Orogenic Belt to the southwest(... The southeastern Alxa Block(i.e.,the Hexi Corridor)is a tectonic junction between the North China Block(NCB)to the east,the Alxa Block to the north,and the western Qinling–North Qilian Orogenic Belt to the southwest(Fig.1).The southeastern Alxa Block had undergone 展开更多
关键词 NW China Geochronology and Tectonic Implications of Diabase Intruded Into Xiangshan Group in the Southeastern Alxa block
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Pseudophacomorphic Glaucoma Along with Pupillary Block after Visian<sup>TM</sup>Implantable Collamer Lens Implantation for High Myopia 被引量:3
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作者 Michael V. McCaughey Thomas R. Mifflin +2 位作者 Carlton R. Fenzl Jason A. Goldsmith Majid Moshirfar 《Open Journal of Ophthalmology》 2014年第4期107-111,共5页
Purpose: To report a case of bilateral glaucoma related to pseudophacomorphic mechanism in one eye and pupillary block in the other eye after Visian Implantable Collamer Lens (ICL;STAAR Surgical) insertion. Methods: A... Purpose: To report a case of bilateral glaucoma related to pseudophacomorphic mechanism in one eye and pupillary block in the other eye after Visian Implantable Collamer Lens (ICL;STAAR Surgical) insertion. Methods: A 44-year-old female with high myopia underwent bilateral ICL implantation of MICL12.6 after sulcus diameter measurements were performed by Pentacam. Results: Pseudophacomorphic glaucoma-related angle closure occurred due to lens oversizing in the right eye. The mechanism was relieved via ICL explantation. In the left eye, pupillary block developed in a subacute manner after closure of the Peripheral Iridotomy (PI). The attack was ameliorated by reestablishing patency of the iridotomy. Conclusions: ICL-related glaucomatous attacks may result from improper sizing as well as from placement of a single PI. Identification of the proper mechanism is vital as treatments differ significantly. In pseudo phacomorphic glaucoma, explantation is needed. In pupillary block glaucoma, treatment involves establishment of a patent PI. 展开更多
关键词 Pseudophacomorphic GLAUCOMA Visian ICL Pupillary block
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The Type and Evolution of Neoproterozoic Sedimentary Basin in the Dahongshan Region,Northern Margin of the Yangtze Block:An Insight from Sedimentary Characteristics of the Huashan Group 被引量:3
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作者 DENG Qi WANG Jian +3 位作者 CUI Xiaozhuang WANG Zhengjiang SHI Meifeng MA Long 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第5期1917-1918,共2页
Objective The Huashan group(composed of the lower Hongshansi Formation and the upper Liufangzui Formation)is an important Neoproterozoic stratigraphic unit along the northern margin of the Yangtze Block.Previous doc... Objective The Huashan group(composed of the lower Hongshansi Formation and the upper Liufangzui Formation)is an important Neoproterozoic stratigraphic unit along the northern margin of the Yangtze Block.Previous documents have focused on the geochronological and geochemical aspects of the Neoproterozoic sedimentary basin in the Dahongshan region.However. 展开更多
关键词 The Type and Evolution of Neoproterozoic Sedimentary Basin in the Dahongshan Region Northern Margin of the Yangtze block
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Investigation of block foundations resting on soil-rock and rock-rock media under coupled vibrations 被引量:1
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作者 Renuka Darshyamkar Ankesh Kumar Bappaditya Manna 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第2期305-317,共13页
In the present study,the dynamic response of block foundations of different equivalent radius to mass(R;/m) ratios under coupled vibrations is investigated for various homogeneous and layered systems.The frequency-d... In the present study,the dynamic response of block foundations of different equivalent radius to mass(R;/m) ratios under coupled vibrations is investigated for various homogeneous and layered systems.The frequency-dependent stiffness and damping of foundation resting on homogeneous soils and rocks are determined using the half-space theory.The dynamic response characteristics of foundation resting on the layered system considering rock-rock combination are evaluated using finite element program with transmitting boundaries.Frequencies versus amplitude responses of block foundation are obtained for both translational and rotational motion.A new methodology is proposed for determination of dynamic response of block foundations resting on soil-rock and weathered rock-rock system in the form of equations and graphs.The variations of dimensionless natural frequency and dimensionless resonant amplitude with shear wave velocity ratio are investigated for different thicknesses of top soil/weathered rock layer.The dynamic behaviors of block foundations are also analyzed for different rock-rock systems by considering sandstone,shale and limestone underlain by basalt.The variations of stiffness,damping and amplitudes of block foundations with frequency are shown in this study for various rock—rock combinations.In the analysis,two resonant peaks are observed at two different frequencies for both translational and rotational motion.It is observed that the dimensionless resonant amplitudes decrease and natural frequencies increase with increase in shear wave velocity ratio.Finally,the parametric study is performed for block foundations with dimensions of 4 m × 3 m × 2 m and 8m×5m×2m by using generalized graphs.The variations of natural frequency and peak displacement amplitude are also studied for different top layer thicknesses and eccentric moments. 展开更多
关键词 Rock-rock system block foundation Coupled vibration Homogeneous medium Equivalent radius to mass ratio Half-space theory
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SYNTHESIS AND CHARACTERIZATION OF WELL-DEFINED BLOCK COPOLYMERS CONTAINING PENDANT,SELF-COMPLEMENTARY QUADRUPLE HYDROGEN BONDING SITES 被引量:1
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作者 唐黎明 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第6期767-774,共8页
The title block copolymer (defined as PSUEA) containing pendant,self-complementary quadruple hydrogen bonding sites has been prepared successfully by three steps.First,poly(styrene-b-2-hydroxyethyl acrylate) (defined ... The title block copolymer (defined as PSUEA) containing pendant,self-complementary quadruple hydrogen bonding sites has been prepared successfully by three steps.First,poly(styrene-b-2-hydroxyethyl acrylate) (defined as PSHEA) was prepared by living radical polymerizing 2-hydroxyethyl acrylate (HEA) initiated by polystyrene (PSt) macro- initiator,which was prepared via nitroxide-mediated polymerization (NMP) technique.After treated by excessive 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI),... 展开更多
关键词 block polymer Controlled radical polymerization Nitroxide-mediated polymerization (NMP) Quadruple hydrogen bonding.
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