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Urban Impact on Landfalling Tropical Cyclone Precipitation:A Numerical Study of Typhoon Rumbia(2018) 被引量:1
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作者 Xinguan DU Haishan CHEN +1 位作者 qingqing li Xuyang GE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第6期988-1004,共17页
Coastal urban areas are prone to serious disasters caused by landfalling tropical cyclones(TCs). Despite the crucial role of urban forcing in precipitation, how fine-scale urban features impact landfalling TC precipit... Coastal urban areas are prone to serious disasters caused by landfalling tropical cyclones(TCs). Despite the crucial role of urban forcing in precipitation, how fine-scale urban features impact landfalling TC precipitation remains poorly understood. In this study, high-resolution ensemble simulations of Typhoon Rumbia(2018), which crossed the Yangtze River Delta urban agglomeration, were conducted to analyze the potential urban impact on TC precipitation. Results show that the inner-core rainfall of Rumbia is strengthened by approximately 10% due to the urban impact near the landfall,whereas minor differences in outer-core rainfall are found when the urban impact is excluded. Further diagnostic analyses indicate that low-level upward motion is crucial for precipitation evolution, as both co-vary during landfall. Moreover, the frictionally induced upward motion plays a decisive role in enhancing the rainfall when the urban impacts are included.Urban surface friction can decelerate the tangential wind and therefore destroy the gradient balance and strengthen the radial wind within the boundary layer and thus can enhance upward motion. This study demonstrates that urban surface friction and related physical processes make the most significant contribution to landfalling TC rainfall enhancement. 展开更多
关键词 landfalling tropical cyclone urban agglomeration quantitative diagnosis rainfall physical mechanisms surface friction
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Clinical Study on Evaluation of Autonomic Nervous Dysfunction Based on Imaging Urodynamic Examination with Slow Filling and Synchronous Blood Pressure Monitoring in the Patients with Cervicothoracic Spinal Cord Injury
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作者 qingqing li Hui Chen +4 位作者 Xihui Xiao Weibin Zeng Shuqing Wu Maping Huang Xinghua Yang 《Open Journal of Urology》 2021年第4期112-123,共12页
<strong>Objective:</strong> Explore the rule of autonomic nervous dysfunction in the patients with urination disorder after high level spinal cord injury, and seek a safe, objective and accurate method to ... <strong>Objective:</strong> Explore the rule of autonomic nervous dysfunction in the patients with urination disorder after high level spinal cord injury, and seek a safe, objective and accurate method to evaluate autonomic nervous function. <strong>Patients and Method:</strong> 48 patients with dysuria after cervicothoracic SCI were selected. Before, during and after imaging urodynamic examination with slow filling in supine position, blood pressure and ECG were monitored simultaneously. The symptoms of sweating, shivering, headache, flushing and chills were observed and recorded. The study of the relationship among the changes of blood pressure, heart rate and urodynamic indexes and the above symptoms was analyzed. <strong>Results:</strong> They were divided into three groups: group A (no obvious abnormality), group B (hyperactivity) and group C (hypoactivity) according to their BP, HR and existing the symptoms or not. <strong>Conclusion:</strong> The incidence of autonomic dysfunction in the high level SCI patients with dysuria was very high (79.17%), most of them were hyperactivity, and a few were low function. The changes of SBP and DBP in the hypoactivity group all appeared an increasing and then declining trend, while the change of HR in the low function one was lower than normal and decreased continuously. The main inducements of AD are neurogenic detrusor overactivity, detrusor sphincter dyssynergia, elevated abdominal pressure and abnormal bladder sensitivity. The asymptomatic patients had a higher occurrence rate (43.75%). Only by imaging urodynamic examination with slow filling and synchronous blood pressure monitoring, can autonomic nervous function of the patients be evaluated safely, objectively, early and accurately. 展开更多
关键词 High Level Spinal Cord Injury Autonomic Nervous Function Imaging Urodynamic Examination Slow Filling Synchronous Blood Pressure Monitoring
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Catgut Implantation at Baliao and Xingfu One Acupuncture Point to Treat Dysdefecation in Patients with Incomplete Spinal Cord Injury: Three Cases Report
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作者 qingqing li Laiming Yu +6 位作者 Hui Chen Ruzhi Zhang Xinghua Yang Qiuling liu Maping Huang Dahui Zhang Shuqing Wu 《Open Journal of Urology》 2020年第6期211-216,共6页
<strong>Objective:</strong> To probe into the effect of catgut implantation at Baliao and Xingfu One Acupuncture Point on dysdefecation in patients with incomplete spinal cord injury (SCI). <strong>M... <strong>Objective:</strong> To probe into the effect of catgut implantation at Baliao and Xingfu One Acupuncture Point on dysdefecation in patients with incomplete spinal cord injury (SCI). <strong>Methods:</strong> Three SCI patients voluntarily accepted catgut embedding at Baliao and Xingfu One Acupuncture point. Before and after treatment, they were filled out the self-rating scale of defecation, including the data of defecation frequency, total defecation time, defecation effort, fecal texture, fecal characteristics and fecal incontinence, etc. <strong>Results:</strong> Compared with the baseline data, constipation was improved and fecal incontinence was disappeared. <strong>Conclusions:</strong> Catgut implantation at Baliao and Xingfu One Acupuncture Point is effectual for patients with neurogenic dysporia secondary to incomplete SCI. 展开更多
关键词 BALIAO Xingfu One Acupuncture Point Catgut Implantation Spinal Cord Injury Dysdefecation
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Catgut Implantation at Baliao and Xingfu One Acupuncture Point to Treat Urinary Incontinence in Patients with Incomplete Spinal Cord Injury: Three Cases Report 被引量:1
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作者 qingqing li Laiming Yu +6 位作者 Hui Chen Ruzhi Zhang Qiuling liu Maping Huang Dahui Zhang Shuqing Wu Jing liu 《Open Journal of Urology》 2019年第8期115-118,共4页
Objective: To explore the effect of catgut implantation at Baliao and Xingfu One Acupuncture point for patients with urinary incontinence secondary to spinal cord injury (SCI). Methods: Three SCI patients received cat... Objective: To explore the effect of catgut implantation at Baliao and Xingfu One Acupuncture point for patients with urinary incontinence secondary to spinal cord injury (SCI). Methods: Three SCI patients received catgut embedding at Baliao and Xingfu One Acupuncture point. The data of intermittent catheterization (IC) volume, intermittent catheterization frequency and the amount of using urine pad (urethral condom) were corrected. Results: Compared to the baseline data, IC volume increased and the leakage volume decreased. Conclusions: Catgut Implantation at Baliao and Xingfu One Acupuncture point is effective for patients with urinary incontinence secondary to incomplete SCI. 展开更多
关键词 BALIAO and Xingfu ONE Acupuncture Point CATGUT IMPLANTATION Spinal Cord Injury URINARY INCONTINENCE
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Zn nanosheets:An earth-abundant metallic catalyst for efficient electrochemical ammonia synthesis
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作者 qingqing li Jing Wang +1 位作者 Yonghua Cheng Ke Chu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第3期318-322,共5页
Ammonia(NH_(3)),a critical raw material for various industrial chemicals,is also recognized as a clean and efficient energy carrier for the future energy economy[1].However,the industrial-scale production of NH_(3) st... Ammonia(NH_(3)),a critical raw material for various industrial chemicals,is also recognized as a clean and efficient energy carrier for the future energy economy[1].However,the industrial-scale production of NH_(3) strongly relies on the Haber-Bosch process,which involves massive fuel consumption and enormous greenhouse gas emissions[2].Therefore,there is an urgent need to develop sustainable and energy-saving alternative routes for artificial NH3 production. 展开更多
关键词 Electrocatalytic nitrogen fixation Metallic catalysts Zn nanosheets N2 activation First-principle calculations
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Additive manufacturing of Ni-based superalloys: Residual stress, mechanisms of crack formation and strategies for crack inhibition 被引量:9
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作者 Chuan Guo Gan li +8 位作者 Sheng li Xiaogang Hu Hongxing Lu Xinggang li Zhen Xu Yuhan Chen qingqing li Jian Lu Qiang Zhu 《Nano Materials Science》 EI CAS CSCD 2023年第1期53-77,共25页
The additive manufacturing(AM)of Ni-based superalloys has attracted extensive interest from both academia and industry due to its unique capabilities to fabricate complex and high-performance components for use in hig... The additive manufacturing(AM)of Ni-based superalloys has attracted extensive interest from both academia and industry due to its unique capabilities to fabricate complex and high-performance components for use in high-end industrial systems.However,the intense temperature gradient induced by the rapid heating and cooling processes of AM can generate high levels of residual stress and metastable chemical and structural states,inevitably leading to severe metallurgical defects in Ni-based superalloys.Cracks are the greatest threat to these materials’integrity as they can rapidly propagate and thereby cause sudden and non-predictable failure.Consequently,there is a need for a deeper understanding of residual stress and cracking mechanisms in additively manufactured Ni-based superalloys and ways to potentially prevent cracking,as this knowledge will enable the wider application of these unique materials.To this end,this paper comprehensively reviews the residual stress and the various mechanisms of crack formation in Ni-based superalloys during AM.In addition,several common methods for inhibiting crack formation are presented to assist the research community to develop methods for the fabrication of crack-free additively manufactured components. 展开更多
关键词 Additive manufacturing Ni-based superalloys Residual stress Mechanisms of crack formation Methods of crack inhibition
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A Lagrangian Trajectory Analysis of Azimuthally Asymmetric Equivalent Potential Temperature in the Outer Core of Sheared Tropical Cyclones
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作者 Yufan DAI qingqing li +1 位作者 Xinhang liU lijuan WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第9期1689-1706,共18页
In this study,the characteristics of azimuthally asymmetric equivalent potential temperature(θ_(e))distributions in the outer core of tropical cyclones(TCs)encountering weak and strong vertical wind shear are examine... In this study,the characteristics of azimuthally asymmetric equivalent potential temperature(θ_(e))distributions in the outer core of tropical cyclones(TCs)encountering weak and strong vertical wind shear are examined using a Lagrangian trajectory method.Evaporatively forced downdrafts in the outer rainbands can transport low-entropy air downward,resulting in the lowestθ_(e)in the downshear-left boundary layer.Quantitative estimations ofθ_(e)recovery indicate that air parcels,especially those originating from the downshear-left outer core,can gradually revive from a low entropy state through surface enthalpy fluxes as the parcels move cyclonically.As a result,the maximumθ_(e)is observed in the downshear-right quadrant of a highly sheared TC.The trajectory analyses also indicate that parcels that move upward in the outer rainbands and those that travel through the inner core due to shear make a dominant contribution to the midlevel enhancement ofθ_(e)in the downshear-left outer core.In particular,the former plays a leading role in suchθ_(e)enhancements,while the latter plays a secondary role.As a result,moist potential stability occurs in the middle-to-lower troposphere in the downshear-left outer core. 展开更多
关键词 tropical cyclone vertical wind shear outer core asymmetric equivalent potential temperature trajectory analysis
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Cherenkov Radiation:A Stochastic Differential Model Driven by Brownian Motions
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作者 qingqing li Zhiwen Duan Dandan Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期155-168,共14页
With the development of molecular imaging,Cherenkov optical imaging technology has been widely concerned.Most studies regard the partial boundary flux as a stochastic variable and reconstruct images based on the stead... With the development of molecular imaging,Cherenkov optical imaging technology has been widely concerned.Most studies regard the partial boundary flux as a stochastic variable and reconstruct images based on the steadystate diffusion equation.In this paper,time-variable will be considered and the Cherenkov radiation emission process will be regarded as a stochastic process.Based on the original steady-state diffusion equation,we first propose a stochastic partial differential equationmodel.The numerical solution to the stochastic partial differential model is carried out by using the finite element method.When the time resolution is high enough,the numerical solution of the stochastic diffusion equation is better than the numerical solution of the steady-state diffusion equation,which may provide a new way to alleviate the problem of Cherenkov luminescent imaging quality.In addition,the process of generating Cerenkov and penetrating in vitro imaging of 18 F radionuclide inmuscle tissue are also first proposed by GEANT4Monte Carlomethod.The result of the GEANT4 simulation is compared with the numerical solution of the corresponding stochastic partial differential equations,which shows that the stochastic partial differential equation can simulate the corresponding process. 展开更多
关键词 Cherenkov radiation stochastic partial differential equations numerical approximation and analysis GEANT4 Monte Carlo simulation
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Combined Detrusor and External Urethral Sphincter BTX-A Injections for Detrusor Overactivity and Detrusor External Sphincter Dyssynergia Secondary to Spinal Cord Injury
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作者 Maping Huang Heyi Zhen +4 位作者 Tianhai Huang Xiaoyi Yang Qiuling liu qingqing li Hui Chen 《Open Journal of Urology》 2021年第2期45-51,共7页
<strong>Objective:</strong> To evaluate the efficacy and safety of Combined detrusor and external urethral sphincter BTX-A injections for detrusor overactivity (DO) and detrusor external sphincter dyssyner... <strong>Objective:</strong> To evaluate the efficacy and safety of Combined detrusor and external urethral sphincter BTX-A injections for detrusor overactivity (DO) and detrusor external sphincter dyssynergia (DESD) secondary to spinal cord injury. <strong>Study Design:</strong> Prospective study. <strong>Methods:</strong> The study was carried out in 18 SCI patients with detrusor overactivity (DO) and detrusor external sphincter dyssynergia (DESD) receiving Combined detrusor and external urethral sphincter BTX-A injections treatment. Contain 200 U botulinum toxin intradetrusor and 100 U external urethral sphincter injections. The effective outcomes included maximum detrusor pressure at first DO and DESD (PdetmaxDO-DESD), volume at first DO and DESD (VDO-DESD), maximum urethral closure pressure (MUCP), and Incontinence-Specific Quality-of-Life Instrument (I-QoL). Adverse events were recorded. <strong>Results:</strong> All patients experienced a significant mean reduction in PdetmaxDO-DESD (50.75%), maximum urethral closure pressure (26.34%) and a significant mean increase in VDO-DESD (63.00%) 12-weeks post-injection. Significant (p < 0.001) improvement in mean Incontinence-Specific Quality-of-Life Instrument was also found. No obvious adverse event and toxic effect was observed. <strong>Conclusion:</strong> Combined detrusor and external urethral sphincter BTX-A injections is a good choice for patients with DO and DESD secondary to spinal cord injury. It could not only protect the upper urinary tract but also improve quality of life. 展开更多
关键词 Detrusor Overactivity Detrusor External Sphincter Dyssynergia BTX-A Spinal Cord Injury
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Initial Experience with Mirabegron for the Treatment of Neurogenic Lower Urinary Tract Dysfunction
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作者 Heyi Zhen Tianhai Huang +4 位作者 Xiaoyi Yang Qiuling liu qingqing li Maping Huang Hui Chen 《Open Journal of Urology》 2021年第8期305-311,共7页
<strong>Background: </strong>Though anticholinergic drugs are considered the standard treatment for neurogenic detrusor overactivity, it is far from an ideal tool, because of their adverse effects such as ... <strong>Background: </strong>Though anticholinergic drugs are considered the standard treatment for neurogenic detrusor overactivity, it is far from an ideal tool, because of their adverse effects such as Constipation or not respond sufficiently for a substantial proportion of patients. Recently mirabegron has become a commonly used overactive bladder medication in the general population, but few studies about mirabegron for the treatment of neurogenic detrusor overactivity. <strong>Objective:</strong> To evaluate the efficacy and safety of mirabegron for the treatment of neurogenic lower urinary tract dysfunction. <strong>Study Design:</strong> Prospective study. <strong>Methods:</strong> This prospective study included 13 adult patients with neurogenic lower urinary tract dysfunction as a result of spinal cord injury. All patients receiving mirabegron treatment (50 mg once daily) at least 6 weeks. The effective outcomes included the mean urine volume per catheterization, urinary incontinence episodes and Incontinence Specific Quality of Life Instrument. We monitored the blood pressure and heart rate to assess the cardiovascular safety, other adverse events were also recorded. <strong>Results:</strong> A total of 13 patients were included. After 6 weeks of treatment, all patients experienced a significant increase in the mean volume of per catheterization from 238.46 ± 65.43 ml to 327.69 ± 59.04 ml (p = 0.001). There is a significant reduction in the volume of urine leakage (463.85 ± 247.98 ml VS 180.00 ± 190.96 ml, p = 0.003) and incontinence episodes per 24 h (4.46 ± 2.03 VS 1.92 ± 1.50, p = 0.001). Significant improvement in mean Incontinence Specific Quality of Life Instrument was also found (p = 0.001). No patients reported dry mouth during the study, and the cardiovascular safety were acceptable. <strong>Conclusion:</strong> Mirabegron is safe and effective in the treatment of neurogenic lower urinary tract dysfunction. It might be a good choice for reducing the cessation of clean intermittent catheterization. 展开更多
关键词 Neurogenic Lower Urinary Tract MIRABEGRON Detrusor Overactivity Spinal Cord Injury
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Autonomic Dysreflexia Severity between Urodynamics and Cystoscopy in Patients with Spinal Cord Injury above T6
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作者 Heyi Zhen Tianhai Huang +4 位作者 Xiaoyi Yang Qiuling liu qingqing li Maping Huang Hui Chen 《International Journal of Clinical Medicine》 2021年第8期351-356,共6页
<strong>Objective:</strong> The objective is to evaluate autonomic dysreflexia (AD) severity between urodynamics and cystoscopy in patients with spinal cord injury (SCI) above thoracic 6 (T6). <strong&g... <strong>Objective:</strong> The objective is to evaluate autonomic dysreflexia (AD) severity between urodynamics and cystoscopy in patients with spinal cord injury (SCI) above thoracic 6 (T6). <strong>Design:</strong> It is a cross-sectional survey. <strong>Subject and methods: </strong>The study was carried out in 22 patients with SCI above T6 who underwent both procedures of urodynamics and cystoscopy;all patients developed episodes of AD. The systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured and recorded at the beginning and during the various stages of the two examinations. AD was defined as a rise in SBP above 20 mm Hg. <strong>Results: </strong>There was no significant difference in SBP and DBP at baseline before urodynamics and cystoscopy. Both urodynamics and cystoscopy triggered episodes of AD. The volume of water instilled during cystoscopy was typically standard and smaller (150 mL) in comparison with urodynamics, where volume varied depending on cystometric bladder capacity (the mean bladder volume in our study was 234.86 ± 139.06 mL). The SBP was significantly different between cystoscopy and urodynamics (49.23 ± 23.07 mm Hg and 35.14 ± 15.75 mm Hg, respectively;P = 0.023). <strong>Conclusions: </strong>Although bladder distension during cystoscopy was less than that in urodynamics, the severity of AD was more pronounced during cystoscopy. It is recommended that monitoring of cardiovascular parameters during these procedures should be routinely performed. 展开更多
关键词 Autonomic Dysreflexi Spinal Cord Injury URODYNAMICS CYSTOSCOPY
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煤层气等压吸附实验研究
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作者 马东民 慕甜 +6 位作者 戴楠 李倩 相里海龙 杨甫 李庆庆 何倩 张晨阳 《地球科学前沿(汉斯)》 2018年第1期19-31,共13页
为厘定温度对煤层气吸附量的影响关系,采集彬长大佛寺煤矿4#长焰煤、佳县上高寨勘查区11#焦煤及晋城寺河煤矿东翼3#无烟煤,制备成空气干燥基样和平衡水样,分别进行25℃、30℃、35℃、40℃、45℃五个温度点的等温吸附/解吸实验。结果表明... 为厘定温度对煤层气吸附量的影响关系,采集彬长大佛寺煤矿4#长焰煤、佳县上高寨勘查区11#焦煤及晋城寺河煤矿东翼3#无烟煤,制备成空气干燥基样和平衡水样,分别进行25℃、30℃、35℃、40℃、45℃五个温度点的等温吸附/解吸实验。结果表明,同一温度点下,空气干燥基的吸附量基本大于平衡水样的吸附量;对实验数据进行拟合分析,发现吸附过程与解吸过程中,等压点的温度与吸附量呈线性关系。研究结果可应用于深部煤层气含气量预测、排采井等压面–采收半径的判定。 展开更多
关键词 煤层气 温度 吸附量 等压吸附
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The impact of endplate fracture on postoperative vertebral height loss and kyphotic deformity during treatment of osteoporotic vertebral compression fractures with balloon kyphoplasty 被引量:6
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作者 qingqing li Long Xiao +4 位作者 Jianwei Zhang Jin Fan Wei Zhou Guoyong Yin Yongxin Ren 《The Journal of Biomedical Research》 CAS CSCD 2016年第5期419-426,共8页
This retrospective study investigated the impact of endplate fracture on postoperative vertebral height loss and kyphotic deformity in 144 patients with osteoporotic vertebral compression fracture (OVCF), who receiv... This retrospective study investigated the impact of endplate fracture on postoperative vertebral height loss and kyphotic deformity in 144 patients with osteoporotic vertebral compression fracture (OVCF), who received balloon kyphoplasty. Patients were divided into four groups: Group 1 had no superior endplate fracture, Group 2 had fractures on the anterior portion of the superior endplate, Group 3 had fractures on the posterior portion of the superior endplate, and Group 4 had complete superior endplate fractures. Anterior and middle vertebral body height, vertebral compression ratio, vertebral height loss rate, and kyphosis Cobb angle of each patient were measured and visual analogue scale (VAS) and Oswestry disability index (ODI) scores were recorded. The anterior vertebral height and kyphosis deformity of all groups significantly improved after the surgery, whereas substantial anterior vertebral height loss and increased Cobb angle were observed in all patients at the last follow-up. Although the vertebral height loss rate and the Cobb angle in Group 2, 3 and 4 were larger compared with Group 1 at the last follow-up, only the vertebral height loss rate in Group 4 and the increase in the Cobb angle in Group 2 and 4 were statistically different from those in Group 1. The VAS and ODI scores in all groups measured after the surgery and at the last follow-up were significantly lower compared with preoperative scores, but there was no significant difference among these groups. Balloon kyphoplasty significantly improved vertebral fracture height and kyphosis. Vertebral height loss and increased kyphotic deformity were observed in OVCF patients with endplate fractures after the surgery. Postoperative aggravation of kyphosis was observed in Group 2. Furthermore, severe vertebral height loss and increased kyphotic deformity were confirmed in Group 4 after the surgery. Our results suggested that postoperative vertebral height loss and aggravation of kyphosis may be associated with biomechanical changes in the vertebral body caused by endplate fracture. Therefore, surgery should not only restore compressed vertebral body height and correct kyphosis, but also correct the deformity of endplate to achieve an effective treatment of OVCF patients with endplate fracture. 展开更多
关键词 osteoporotic vertebral compression fracture balloon kyphoplasty endplate fracture height loss KYPHOSIS
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Characteristics of the Outer Rainband Stratiform Sector in Numerically Simulated Tropical Cyclones:Lower-Layer Shear versus Upper-Layer Shear 被引量:5
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作者 Qi GAO qingqing li Yufan DAI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第4期399-419,共21页
Idealized numerical simulations are conducted in this study to comparatively investigate the characteristics of the stratiform sector in the outer rainbands of tropical cyclones(TCs)in lower-and upper-layer vertical w... Idealized numerical simulations are conducted in this study to comparatively investigate the characteristics of the stratiform sector in the outer rainbands of tropical cyclones(TCs)in lower-and upper-layer vertical wind shear(VWS)with moderate magnitude.Consistent with the results in previous studies,the outer rainband stratiform sector of the TCs simulated in both experiments is generally located downshear left.Upper-layer VWS tends to produce stronger asymmetric outflow at upper levels in the downshear-left quadrant than lower-layer shear.This stronger asymmetric outflow transports more water vapor radially outward from the inner core to the outer core at upper levels in the downshear-left quadrant in the upper-layer shear experiment.More depositional growth of both graupel and cloud ice thus occurs downshear left in upper layers in the outer core,yielding more diabatic heating and stronger upward motions,particularly in the stratiformdominated part of the stratiform sector in the upper-layer shear experiment.Resultingly,a better-organized stratiform sector in the outer rainbands is found in the upper-layer VWS experiment than in the lower-layer VWS experiment.The diabatic heating associated with the stratiform sector produces strong midlevel outflow on the radially inward side of,and weak midlevel inflow on the radially outward side of,the heating core,with lower-level inflow beneath the midlevel outflow and upper-level inflow above.The upper-layer VWS tends to produce a deeper asymmetric inflow layer in the outer rainband stratiform sector,with more significant lower-level inflow and tangential jets in the upper-layer VWS experiment. 展开更多
关键词 STRATIFORM outer rainband TROPICAL CYCLONE vertical wind shear
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Amorphization activated FeB_(2) porous nanosheets enable efficient electrocatalytic N_(2) fixation 被引量:4
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作者 Ke Chu Weicong Gu +3 位作者 qingqing li Yaping liu Ye Tian Wuming liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第2期82-89,I0004,共9页
Designing active,robust and cost-effective catalysts for the nitrogen reduction reaction(NRR) is of paramount significance for sustainable electrochemical NH3 synthesis.Transition-metal diborides(TMB_2)have been recen... Designing active,robust and cost-effective catalysts for the nitrogen reduction reaction(NRR) is of paramount significance for sustainable electrochemical NH3 synthesis.Transition-metal diborides(TMB_2)have been recently theoretically predicted to be a new class of potential NRR catalysts,but direct experimental evidence is still lacking.Herein,we present the first experimental demonstration that amorphous FeB_2 porous nanosheets(a-FeB_2 PNSs) could be a highly efficient NRR catalyst,which exhibited an NH3 yield of 39.8 μg h^(-1) mg^(-1)(-0.3 V) and a Faradaic efficiency of 16.7%(-0.2 V),significantly outperforming their crystalline counterpart and most of existing NRR catalysts.First-principle calculations unveiled that the amorphization could induce the upraised d-band center of a-FeB_2 to boost d-2π~* coupling between the active Fe site and ~*N_2 H intermediate,resulting in enhanced ~*N_2 H stabilization and reduced reaction barrier.Out study may facilitate the development and understanding of earth-abundant TMB_2-based catalysts for electrocatalytic N_2 fixation. 展开更多
关键词 Electrocatalytic nitrogen fixation Transition-metal diborides Amorphization Density functional theory
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A comparison of robot-assisted and fluoroscopy-assisted kyphoplasty in the treatment of multi-segmental osteoporotic vertebral compression fractures 被引量:5
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作者 qingqing li Chaoqin Wu +6 位作者 Zhenfei Huang Jiang Cao Jie Chang Guoyong Yin lipeng Yu Xiaojian Cao Tao Sui 《The Journal of Biomedical Research》 CAS CSCD 2022年第3期208-214,共7页
Osteoporotic vertebral compression fracture(OVCF)has become a major public health issue that becomes more pressing with increasing global aging.Percutaneous kyphoplasty(PKP)is an effective treatment for OVCF.Robot-ass... Osteoporotic vertebral compression fracture(OVCF)has become a major public health issue that becomes more pressing with increasing global aging.Percutaneous kyphoplasty(PKP)is an effective treatment for OVCF.Robot-assisted PKP has been utilized in recent years to improve accuracy and reduce complications.However,the effectiveness of robot-assisted PKP in the treatment of multi-segmental OVCF has yet to be proved.This study was designed to compare the efficacy of robot-assisted and conventional fluoroscopy-assisted multi-segmental PKP.A total of 30 cases with multi-segmental OVCF between April 2019 and April 2021 were included in this study.Fifteen cases were assigned to the robot-assisted PKP group(robot group)and 15 cases to the conventional fluoroscopy-assisted PKP group(conventional fluoroscopy group).The number of fluoroscopic exposures,fluoroscopic dose,operation time,cement leakage rate,visual analog scale(VAS)score,vertebral kyphosis angle(VKA),and height of fractured vertebral body(HFV)were compared between the 2 groups.The number of fluoroscopic exposures,fluoroscopic doses,and cement leakage rates in the robot group were lower than in the conventional fluoroscopy group(P<0.05)while the operative time in the robot group was longer than in the conventional fluoroscopy group(P<0.05).VAS score and VKA were decreased and HFV was increased after surgery in both groups(P<0.05).Therefore,robot-assisted PKP for the treatment of multi-segmental OVCF can reduce the number of fluoroscopic exposures,fluoroscopic doses,and cement leakage compared to conventional treatment.As such,robot-assisted PKP has good application prospects and is potentially more effective in the treatment of multi-segmental OVCF. 展开更多
关键词 spinal fracture percutaneous kyphoplasty ROBOT-ASSISTED
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Re-examining Tropical Cyclone Fullness Using Aircraft Reconnaissance Data 被引量:2
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作者 Zhehan CHEN qingqing li 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第9期1596-1607,共12页
We use FLIGHT+ aircraft reconnaissance data for tropical cyclones(TCs) in the North Atlantic and Eastern Pacific from 1997 to 2015 to re-examine TC fullness(TCF) characteristics at the flight level.The results show a ... We use FLIGHT+ aircraft reconnaissance data for tropical cyclones(TCs) in the North Atlantic and Eastern Pacific from 1997 to 2015 to re-examine TC fullness(TCF) characteristics at the flight level.The results show a strong positive correlation between the flight-level TCF and the intensity of TCs,with the flight-level TCF increasing much more rapidly than the near-surface TCF with increasing intensity of the TCs.The tangential wind in small-TCF hurricanes is statistically significantly stronger near the eye center than that in large-TCF hurricanes.Large-TCF hurricanes have a ring-like vorticity structure.No significant correlation is observed between the flight-level TCF and the comparative extent of the vorticityskirt region occupied in the outer core skirt.The proportion of the rapid filamentation zone in the outer core skirt increases with increasing flight-level TCF.The differences in entropy between the radius of the maximum wind and the outer boundary of the outer core skirt also increase with increasing flight-level TCF. 展开更多
关键词 tropical cyclone FULLNESS INTENSITY structure aircraft reconnaissance data
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泛素化途径在奶牛乳脂生成过程中的调控作用 被引量:2
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作者 刘莉莉 郭爱伟 +6 位作者 李青青 吴培福 杨亚晋 陈粉粉 李素华 郭盘江 张勤 《遗传》 CAS CSCD 北大核心 2020年第6期548-555,共8页
泛素化途径是真核细胞中主要的蛋白质降解途径,其中泛素–蛋白酶体途径主要降解细胞质中的蛋白,溶酶体途径主要降解细胞膜蛋白。研究表明,泛素化途径在奶牛乳腺上皮细胞脂肪酸合成过程中起着关键的调控作用。在脂肪酸摄取过程中,泛素化... 泛素化途径是真核细胞中主要的蛋白质降解途径,其中泛素–蛋白酶体途径主要降解细胞质中的蛋白,溶酶体途径主要降解细胞膜蛋白。研究表明,泛素化途径在奶牛乳腺上皮细胞脂肪酸合成过程中起着关键的调控作用。在脂肪酸摄取过程中,泛素化途径调控异常可导致细胞膜上脂肪酸转运蛋白的泛素化降解受阻,使脂肪酸转运增强,进而增加奶牛乳脂的生成。本文综述了泛素化途径在奶牛乳脂生成过程中对相关蛋白的调控作用,以期为奶牛乳脂性状后续相关研究提供参考和新的思路。 展开更多
关键词 泛素化途径 泛素–蛋白酶体系统 溶酶体系统 乳脂生成 脂肪酸
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Amorphous MoS_(3) enriched with sulfur vacancies for efficient electrocatalytic nitrogen reduction 被引量:2
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作者 Ke Chu Haifeng Nan +3 位作者 qingqing li Yali Guo YeTian Wuming liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第2期132-138,I0005,共8页
Developing low-priced,yet effective and robust catalysts for the nitrogen reduction reaction(NRR) is of vital importance for scalable and renewable electrochemical NH3 synthesis.Herein,we provide the first demonstrati... Developing low-priced,yet effective and robust catalysts for the nitrogen reduction reaction(NRR) is of vital importance for scalable and renewable electrochemical NH3 synthesis.Herein,we provide the first demonstration of MoS_3 as an efficient and durable NRR catalyst in neutral media.The prepared amorphous MoS_3 naturally possessed enriched S vacancies and delivered an NH3 yield of 51.7 μg h^(-1) mg^(-1)and a Faradaic efficiency of 12.8% at-0.3 V(RHE) in 0.5 M LiClO_4,considerably exceeding those of MoS_2 and most reported NRR catalysts.Density functional theory calculations unraveled that S vacancies involved in MoS_3 played a crucial role in activating the NRR via a consecutive mechanism with a low energetics barrier and simultaneously suppressing the hydrogen evolution reaction. 展开更多
关键词 Electrocatalytic N_2 reduction Amorphous materials VACANCY N_(2)activation
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Geometric Characteristics of Tropical Cyclone Eyes before Landfall in South China Based on Ground-Based Radar Observations 被引量:2
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作者 Xiaotong ZHU qingqing li +2 位作者 Jinhua YU Dan WU Kai YAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第5期592-603,共12页
The geometric characteristics of tropical cyclone(TC) eyes before landfall in South China are examined using groundbased radar reflectivity. It is found that the median and mean eye area decrease with TC intensity, ... The geometric characteristics of tropical cyclone(TC) eyes before landfall in South China are examined using groundbased radar reflectivity. It is found that the median and mean eye area decrease with TC intensity, except for the severe typhoon category, and the eye size increases with height. The increasing rate of eye size is relatively greater in upper layers.Moreover, the ratio of eye size change in the vertical direction does not correlate with TC intensity. No relationship is presented between the ratio of eye size change in the vertical direction and the vertical wind shear. No relationship between the vertical change in eye size and the eye size at a certain level is found, inconsistent with other studies. No relationship exists between the vertical change in eye size and the intensity tendency. The eye roundness values range mainly from 0.5 to 0.7, and more intense TCs generally have eyes that are more circular. 展开更多
关键词 tropical cyclone eye geometric characteristics pre-landfall
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