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Predictors of pain response after endoscopic ultrasound-guided celiac plexus neurolysis for abdominal pain caused by pancreatic malignancy

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World Journal of Gastroenterology 2021年第1期27卷 69-79页

作者： Chao-Qun Han Xue-Lian Tang Qin Zhang chi nie Jun Liu Zhen Ding Division of Gastroenterology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina

BACKGROUND Endoscopic ultrasound-guided celiac plexus neurolysis(EUS-CPN)has gained popularity as a minimally invasive approach and is currently widely used to treat pancreatic cancer-associated ***,response to treatment is *** To identify the efficacy of EUS-CPN and explore determinants of pain response in EUS-CPN for pancreatic cancer-associated *** A retrospective study of 58 patients with abdominal pain due to inoperable pancreatic cancer who underwent EUS-CPN were *** efficacy for palliation of pain was evaluated based on the visual analog scale pain score at 1 wk and 4 wk after *** and multivariable logistic regression analyses were performed to explore predictors of pain *** A good pain response was obtained in 74.1%and 67.2%of patients at 1 wk and 4 wk,*** located in the body/tail of the pancreas and patients receiving bilateral treatment were weakly associated with a good *** analysis revealed patients with invisible ganglia and metastatic disease were significant factors for a negative response to EUS-CPN at 1 wk and 4 wk,respectively,particularly for invasion of the celiac plexus(odds ratio(OR)=13.20,P=0.003 for 1 wk and OR=15.11,P=0.001 for 4 wk).No severe adverse events were *** EUS-CPN is a safe and effective form of treatment for intractable pancreatic cancer-associated *** ganglia,distant metastasis,and invasion of the celiac plexus were predictors of less effective response in EUS-CPN for pancreatic cancer-related *** these patients,efficacy warrants attention.

关键词： Endoscopic ultrasound Celiac plexus neurolysis Pancreatic cancer Pain Predictor

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PALES: Optimizing Secure Data Deletion in SSDs via Page Group and Reprogram Speedup

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chinese Journal of Electronics 2022年第1期31卷 40-51页

作者： nie Shiqiang WU Weiguo ZHANG chi ZHANG Chen Department of Computer Science and Technology Xi'an Jiaotong University

As solid-state drives(SSD) have been widely adopted, secure data deletion becomes an essential component for ensuring user privacy, preventing sensitive data leakage. Due to the erase-before-write property,erasure operation and scrub operation substituting for overwriting technologies are proposed to meet the requirements. However, both methods bring the severe page-copying issue, declining read/write performance, and shortening the lifetime of SSD. In this paper, this issue is alleviated by reserving pages at the page allocation stage to mitigate program disturbance and increasing program step voltage during reprogramming operation to reduce the reprogram latency. The proposed scheme is evaluated by a series of experiments; the results show that the proposed scheme could achieve significant deletion time reduction and alleviate page-copying overhead.

关键词： reprogramming operation storage management solid-state drives SSD flash memories page group page-copying overhead erase-before-write property secure data deletion PALES data privacy erasure operation page allocation stage user privacy security of data program step voltage sensitive data leakage reprogram speedup

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正常足月儿畸变产物耳声发射(DPOAEs)特性分析

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生物物理学报 1999年第4期15卷 694-694页

作者：戚以胜聂迎玖于小千赵天卫北京市耳鼻咽喉科研究所北京100005 北京海淀妇幼保健院北京100080

研究提出正常足月儿畸变产物耳声发射（ＤＰＯＡＥｓ）特性分析如下：１．ＤＰＯＡＥｓ反应强度曲线，ＤＰ图显示两个反应峰（ｆ２＝１．６和５．０ｋＨｚ）和一个反应谷（ｆ２＝３．１～４．０ｋＨｚ）；２．ＤＰ... 详细信息

研究提出正常足月儿畸变产物耳声发射（ＤＰＯＡＥｓ）特性分析如下：１．ＤＰＯＡＥｓ反应强度曲线，ＤＰ图显示两个反应峰（ｆ２＝１．６和５．０ｋＨｚ）和一个反应谷（ｆ２＝３．１～４．０ｋＨｚ）；２．ＤＰＯＡＥ本底噪声及其特性，ｆ２＝１．０ｋＨｚ其测试频率点（２ｆ１－ｆ２）本底噪声最高（Ｐ＜０．０５），ｆ２＝３．１，４．０和５．０ｋＨｚ，测试频率点（２ｆ１－ｆ２）本底噪声较低（Ｐ＜０．０５）；除ｆ２＝４．０ｋＨｚ外，ＤＰＯＡＥ本底噪声与其反应强度均未呈现直线相关特性；３．ＤＰＯＡＥＳＮＲ特性，ｆ２＝１．０ｋＨｚ其ＳＮＲ最小（Ｐ＝０．０００），ｆ２＝２．０ｋＨｚ其ＳＮＲ最大（Ｐ０．００３）；４．ＤＰＯＡＥＳＮＲ和ＴＥＯＡＥＳＮＲ相关特性，除１．０ｋＨｚ频段外，其余频段其二者间均有着非常显著的直线相关特性。

关键词：畸变产物耳声发射瞬态诱发耳声发射信噪比

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Drill string dynamic characteristics simulation for the ultra-deep well drilling on the south margins of Junggar Basin

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Petroleum 2023年第2期9卷 205-213页

作者： Yuan Li Jianggang Shi Minghu nie chi Peng Yingjie Wang Institute of Petrol Engineering Technology of Petrochina Xinjiang Oilfield Branch KaramayChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Engineering Southwest Petroleum UniversityChengdu610500China

Improper drilling parameters may cause severe vibration of drill string which leads to reduce the rate of penetration and drilling tool premature failure accidents in the drilling process of ultra-deep *** study on dynamic characteristics of drill string plays an important role in increasing the safety of drilling tool and optimizing the drilling *** the influences of real borehole trajectory,interaction between bit and formation,contact between drill string and borehole wall,stiction of drilling fluid and other factors,a comprehensive drill string dynamic model was established to simulate the changes of wellhead hook load,torque,equivalent stress of drill string and BHA(bottomhole assembly)section acceleration and motion trajectory with time at different WOBs(weights on bit)and rotary *** safety factor and overpull margin of wellhead drill string were calculated and the strength of drilling tool in ultra-deep well was checked using the fourth strength *** analysis results show that,in the drilling process of ultra-deep well,the transverse motion amplitude of the drill string near the wellhead is relatively small and vibration of drill string mainly occurs in the lower well *** the rotary speed increases,the number of collision between lower drilling tool and borehole wall increases,wellhead transverse stress increases,change in torque is not large and change in wellhead equivalent stress is relatively *** the WOB increases,wellhead torque will increase,axial load and equivalent stress will decrease and vibration acceleration of BHA will increase *** overpull margin and safety factor will decrease with the increase of rotary speed and increase with the increase of *** safety factor of S135 drilling tool in an F190.5 mm ultra-deep well on the south margins of Junggar basin changes around *** drilling tool is safe and has relatively sufficient ability to deal with the downhole accidents if a l

关键词： Ultra-deep well Drilling tool failure Drill string dynamics Drill string strength check Drilling parameter optimization

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恩施山区一次严重中小河流域山洪事故成因

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湖北农业科学 2022年第S01期61卷 74-81页

作者：罗菊英周建山王珊珊聂池祥湖北省恩施州气象局湖北恩施445000 武汉中心气象台武汉430074 恩施州水文水资源勘测局湖北恩施445000

2019年8月4日,恩施州鹤峰县躲避峡流域因短时强降雨诱发中小河流域山洪暴发,发生13人伤亡的重大灾害事故。本研究利用常规资料,数值预报再分析资料,地面加密雨量站、多普勒雷达和卫星监测资料以及相关水文资料,围绕导致山洪暴发的短时... 详细信息

2019年8月4日,恩施州鹤峰县躲避峡流域因短时强降雨诱发中小河流域山洪暴发,发生13人伤亡的重大灾害事故。本研究利用常规资料,数值预报再分析资料,地面加密雨量站、多普勒雷达和卫星监测资料以及相关水文资料,围绕导致山洪暴发的短时强降雨形成的天气形势背景和中小尺度对流系统特征、水文耦合特征、地形影响等进行综合分析,揭示其致灾成因。结果表明,(1)中高纬度维持“两槽一脊”的大环流背景,对流层中低层受热带低值系统扰动影响,加上高温高湿高能的大气层结不稳定,对午后出现强对流天气有利;(2)鹤峰典型的迎风坡地形抬升作用下在边界层形成局地中小尺度辐合系统,加上躲避峡流域东北—西南带状的峡谷地形,使得峡谷内形成了向后传播持续较长具有MCS模态特征的强对流回波带,是躲避峡流域出现短时强降雨的直接原因;(3)短时强降雨发生后,窄而陡峭的峡谷地形下,致洪雨量阈值偏低,水流快速汇集,上涨速度快、水流速度大,上游遇突发性短时强降雨时,下游人员因来不及避险是导致伤亡事故的重要原因;(4)水文耦合分析结果得出,躲避峡流域洪峰出现一般滞后于短时强降雨2~3 h,故针对短时强降雨诱发中小河流域山洪致灾阀值研究,做好水雨情监测和及时预警,对防范中小河流域灾害事故具有积极意义。

关键词：山区中小河流域山洪灾害

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Experiment of gas diffusion and its diffusion mechanism in coal

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International Journal of Mining Science and Technology 2012年第6期22卷 885-889页

作者： Li Xiangchun nie Baisheng Zhang Ruming chi Leilei School of Resource and Safety Engineering China University of Mining & Technology State Key Laboratory of Coal Resources and Safe Mining

In coal,the gas mainly exists in a free or an adsorption *** the coal containing gas is damaged,gas desorption and diffusion will occur which can result in gas *** research on gas desorption and diffusion provides a theoretical basis for gas disaster mechanism and *** influence of pressure and temperature on gas diffusion is studied by the *** the mechanism of pressure and temperature on gas diffusion is also *** research results indicate that gas diffusion capacity increases with increasing temperature under the same pressure for the same coal *** is mainly because the temperature increases,gas molecular hot motion is severer,kinetic energy of gas molecular increases,and gas desorption quickens,therefore gas diffusion capacity changes *** other unchanged conditions,the greater gas adsorption balance pressure,the more gas adsorption content,and the higher the initial gas *** gas diffusion begins,the greater the gas concentration gradient,the faster the gas diffusion speeds.

关键词： Gas Coal Diffusion Pressure Temperature

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Light-induced variation in environmentally persistent free radicals and the generation of reactive radical species in humic substances

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Frontiers of Environmental Science & Engineering 2020年第6期14卷 171-180页

作者： Yafang Shi Yunchao Dai Ziwen Liu Xiaofeng nie Song Zhao chi Zhang Hanzhong Jia College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China Key Laboratory of Plant Nutrition and the Agri-environment in Northwest china Ministry of AgricultureYangling 712100China

Environmentally persistent free radicals(EPFRs)in humic substances play an essential role in soil geochemical *** is known to induce EPFRs formation for dissolved organic matter in aquatic environments;however,the impacts of light irradiation on the variation of EPFRs in soil humic substances remain *** this study,humic acid,fulvic acid,and humin were extracted from peat soil and then in situ irradiated using simulated *** paramagnetic resonance spectroscopy results showed that with the increasing irradiation time,the spin densities and g-factors of humic substances rapidly increased during the initial 20 min and then gradually reached a *** irradiation for 2h,the maximum spin density levels were up to 1.63×10^17,2.06×10^17,and 1.77×10^×10^17 spins/g for the humic acid,fulvic acid,and humin,*** the superoxide radicals increased to 1.05×10^l4-1.46×10^14spins/g while the alkyl radicals increased to 0.47×10^14-1.76×10^14 spins/*** light-induced EPFRs were relatively unstable and readily returned back to their original state under dark and oxic *** positive correlations were observed between the concentrations of EPFRs and reactive radical species(R2=0.65-0.98,/?<0.05),which suggested that the newly produced EPFRs contributed to the formation of reactive radical *** findings indicate that under the irradiation humic substances are likely to be more toxic and reactive in soil due to the formation of EPFRs.

关键词： Peat Humic substances Environmentally persistent free radicals Light irradiation Reactive radical species

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Methoxy n-fatty acids in surface soils from the Gongga and Kunlun Mountains:Ecological implications

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chinese Science Bulletin 2010年第21期55卷 2258-2267页

作者： BAI Yan FANG XiaoMin nie JunSheng MENG QiangXiang chi YunPing Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Key Laboratory of Western china's Environmental Systems Ministry of Education of China and College of Resources and Environment Lanzhou University Lanzhou 730000 China Department of Geological Sciences Jackson School of Geosciences University of Texas Austin TX 78712 USA Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China

GC-MS characteristics of surface soil samples from the eastern and northern Tibetan Plateau provide tentative identification of 8(-14)-Methoxy hexadecanoic acid(iME-16:0)and 9(-17)-methoxy octadecanoic acid(iME-18:0).Sixty surface soil samples were collected from the eastern slope of Gongga Mountain,at elevations ranging from～1230 to 4500 m(eastern Tibetan Plateau),and from the northern slope of West Kunlun Mountains,ranging from～1300 to 5500 m(northern Tibetan Plateau).This study also analyzed the methoxy n-fatty acids(MFAs)of Gongga Mountain tree leaves from six common living species,at the elevation of 2900-4200 *** dominate these samples,with more centrally located methoxy groups eluting earlier than those with methoxy groups located closer to the end of the main carbon *** occur prominently in most of the Gongga Mountain soil samples(and from six tree samples)from dominantly coniferous and deciduous broadleaved *** than in two narrow vegetation zones between 4000-4350 m and 2900-3300 m,no MFAs were found in 19 Kunlun Mountains soil samples from areas covered mainly with montane desert and alpine desert steppe *** on the inventory of plants and soils from which MFAs have been isolated,we conclude that the MFAs most probably originate from specific woody *** we can exclude some particular grasses as sources,MFAs may be specific woody plants-derived biomarkers;thus they would serve as an important additional proxy for comprehensive and precise ecological reconstructions.

关键词：表层土壤西昆仑山生态重建甲氧基脂肪酸欧米茄青藏高原东部土壤样品

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A novel fractional grey forecasting model with variable weighted buffer operator and its application in forecasting china's crude oil consumption

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Petroleum 2022年第2期8卷 139-157页

作者： Yong Wang Yuyang Zhang Rui nie Pei chi Xinbo He Lei Zhang School of Sciences Southwest Petroleum UniversityChengdu610500China

Oil is an important strategic material and civil *** prediction of oil consumption can provide basis for relevant departments to reasonably arrange crude oil production,oil import and export,and optimize the allocation of social ***,a new grey model FENBGM(1,1)is proposed to predict oil consumption in ***,the grey effect of the traditional GM(1,1)model was transformed into a quadratic *** different parameters were introduced to improve the accuracy of the model,and the new initial conditions were designed by optimizing the initial values by weighted buffer *** with the reprocessing of the original data,the scheme eliminates the random disturbance effect,improves the stability of the system sequence,and can effectively extract the potential pattern of future ***,the cumulative order of the new model was optimized by fractional cumulative generation *** the same time,the smoothness rate quasi-smoothness condition was introduced to verify the stability of the model,and the particle swarm optimization algorithm(PSO)was used to search the optimal parameters of the model to enhance the adaptability of the *** on the above improvements,the new combination prediction model overcomes the limitation of the traditional grey model and obtains more accurate and robust prediction ***,taking the petroleum consumption of china's manufacturing industry and transportation,storage and postal industry as an example,this paper verifies the validity of FENBGM(1,1)model,analyzes and forecasts china's crude oil consumption with several commonly used forecasting models,and uses FENBGM(1,1)model to forecast china's oil consumption in the next four *** results show that FENBGM(1,1)model performs best in all ***,based on the prediction results of FENBGM(1,1)model,some reasonable suggestions are put forward for china's oil consumption planning.

关键词： Grey forecasting model Variable weighted buffer operator Particle swarm optimization Oil consumption forecast

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全国地球化学基准网建立与土壤地球化学基准值特征

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中国地质 2016年第5期43卷 1469-1480页

作者：王学求周建徐善法迟清华聂兰仕张必敏姚文生王玮刘汉粮刘东盛韩志轩柳青青国土资源部地球化学探测技术重点实验室中国地质科学院地球物理地球化学勘查研究所河北廊坊065000 联合国教科文组织全球尺度地球化学国际研究中心河北廊坊065000

全球一致性和权威性地球化学观测数据是资源与环境评价的定量标尺。中国实施的"全国地球化学基准计划"作为"全球地球化学基准计划"的一部分,于2008—2014年实施,建立了覆盖全国的地球化学基准网。按照1∶20万图幅为网格单元,在全国1600... 详细信息

全球一致性和权威性地球化学观测数据是资源与环境评价的定量标尺。中国实施的"全国地球化学基准计划"作为"全球地球化学基准计划"的一部分,于2008—2014年实施,建立了覆盖全国的地球化学基准网。按照1∶20万图幅为网格单元,在全国1600个网格单元中,共部署3382个汇水域采样基准点,每个基准点同时采集了表层和深层土壤样品,共计采集6617件样品,使用高精度分析技术和严格的质量控制,分析了81个地球化学指标。本文首次给出了全国土壤81个指标地球化学基准值数据,初步阐释了地球化学基准值数据和空间分布特征与地质背景、成矿作用、表生作用以及人类活动的关系。

关键词：中国地球化学基准网基准值 76种元素

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