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Exploring Variability in Sea Level at a Tide Gauge Station through Control Charts
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作者 H.Bâkiİz 《Journal of Environmental & Earth Sciences》 CAS 2024年第1期11-18,共8页
Monitoring temporal changes in sea level is important in assessing coastal risk.Sea level anomalies at a tide gauge station,if kinematically conceived,include systematic variations such as trend,acceleration,periodic ... Monitoring temporal changes in sea level is important in assessing coastal risk.Sea level anomalies at a tide gauge station,if kinematically conceived,include systematic variations such as trend,acceleration,periodic oscillations,and random disturbances.Among them,the non-stationary nature of the random sea level variations of known or unknown origin at coastal regions has been long recognized by the sea level community.This study proposes the analyses of subgroups of random residual statistics of a rigorously formulated kinematic model solution of tide gauge variations using X-bar and S control charts.The approach is demonstrated using Key West,Florida tide gauge records.The mean and standard errors of 5-year-long subgroups of the residuals revealed that sea level changes at this location have been progressively intensifying from 1913 to the present.Increasing oscillations in sea level at this locality may be attributed partly to the thermal expansion of seawater with increasing temperatures causing larger buoyancy-related sea level fluctuations as well as the intensification of atmospheric events including wind patterns and the impact of changes in inverted barometer effects that will alter coastal risk assessments for the future. 展开更多
关键词 Climate change sea level variance X-bar s control charts
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Comprehensive effects of traditional Chinese medicine treatment on heart failure and changes in B-type natriuretic peptide levels: A meta-analysis
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作者 Li-Li Xia Shu-Yun Yang +2 位作者 Jun-Yao Xu Han-Qing Chen Zhu-Yuan Fang 《World Journal of Clinical Cases》 SCIE 2024年第4期766-776,共11页
BACKGROUND Heart failure(HF),a common cardiovascular condition,is characterized by significant morbidity and mortality.While traditional Chinese medicine(TCM)is often used as a complementary approach in HF management,... BACKGROUND Heart failure(HF),a common cardiovascular condition,is characterized by significant morbidity and mortality.While traditional Chinese medicine(TCM)is often used as a complementary approach in HF management,systematic evalua-tions of its impact on clinical outcomes,TCM syndrome scores,and B-type natriuretic peptide(BNP)levels are lacking.This study fills this gap through a comprehensive analysis of randomized controlled trials(RCTs)focusing on TCM for HF treatment.It encompasses an assessment of methodological quality,a meta-analysis,and an evaluation of evidence quality based on established standards.The results offer crucial insights into the potential advantages and constraints of TCM in HF management.RCTs on TCM for HF treatment published since the establishment of the database were searched in four Chinese and English databases,including China National Knowledge Infrastructure,Wanfang,VIP Information Chinese Science and Technology Journal,and PubMed.Methodological quality was assessed for the included studies with the Cochrane risk-of-bias assessment tool,and the meta-analysis and publication bias assessment was performed with the RevMan5.3 software.Finally,the quality of evidence was rated according to the GRADE criteria.RESULTS A total of 1098 RCTs were initially retrieved.After screening,16 RCTs were finally included in our study,which were published between 2020 and 2023.These RCTs involved 1660 HF patients,including 832 in the TCM group[TCM combined with conventional Western medicine(CMW)treatment]and 828 in the CWM group(CWM treatment).The course of treatments varied from 1 wk to 3 months.TCM syndrome differentiation was analyzed in 11 of the included RCTs.In all included RCTs,outcome indicators included comprehensive clinical outcomes,TCM syndrome scores,and BNP levels.The meta-analysis results showed significant differences between the TCM and CWM groups in terms of comprehensive clinical outcomes[risk ratio=-0.54;95%confidence interval(CI)=-0.61,-0.47;P<0.00001],TCM syndrome scores[weighted mean difference(WMD)=-142.07;95%CI=-147.56,-136.57;P<0.00001],and BNP levels(WMD=-142.07;95%CI=-147.56,-136.57;P<0.00001).According to the GRADE criteria,RCTs where"TCM improves clinical comprehensive outcomes"were rated as low-quality evidence,and RCTs where"TCM reduces TCM syndrome scores"or"TCM decreases BNP levels"were rated as medium-quality evidence.CONCLUSION TCM combined with CWM treatment effectively improves comprehensive clinical outcomes and diminishes TCM syndrome scores and BNP levels in HF patients.Given the low and medium quality of the included RCTs,the application of these results should be cautious. 展开更多
关键词 Traditional Chinese medicine Heart failure Comprehensive clinical outcomes Traditional Chinese medicine syndrome score B-type natriuretic peptide level Meta-analysis©The Author(s)2024.Published by Baishideng Publishing Group Inc.
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用Level Set方法求解具有自由面的流动问题 被引量:11
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作者 袁德奎 陶建华 《力学学报》 EI CSCD 北大核心 2000年第3期264-271,共8页
为采用 Level Set方法来计算有自由水面的流动问题提出了一种方案.把自由水面视为水和空气的交界面,两种介质用统一的N-S方程求解,在自由面两侧分别采用各自的密度和粘性,并在自由面上给以适当的光滑;采用边界无法求解... 为采用 Level Set方法来计算有自由水面的流动问题提出了一种方案.把自由水面视为水和空气的交界面,两种介质用统一的N-S方程求解,在自由面两侧分别采用各自的密度和粘性,并在自由面上给以适当的光滑;采用边界无法求解双调和方程来确定距离函数;N-S方程用投影法求解.文中给出了二维水池水面振荡和瞬时溃坝问题的算例,可以看出用 Level Set方法求解有自由面流动问题是有效的. 展开更多
关键词 level sET方法 自由面 N-s方程 流动 水动力学
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用LEVEL SET方法计算溃坝波的传播过程 被引量:6
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作者 陶建华 谢伟松 《水利学报》 EI CSCD 北大核心 1999年第10期17-22,共6页
溃坝波的数值模拟在于正确地计算坝体溃决后上下游水面的迅速变化过程. 本文研究了近年发展起来的求解两种流体界面的Level Set 方法及其在具有自由表面的水动力学问题中的应用. 对不同底坡上的二维溃坝波进行了计算, 取得... 溃坝波的数值模拟在于正确地计算坝体溃决后上下游水面的迅速变化过程. 本文研究了近年发展起来的求解两种流体界面的Level Set 方法及其在具有自由表面的水动力学问题中的应用. 对不同底坡上的二维溃坝波进行了计算, 取得了和实验资料符合良好的结果. 展开更多
关键词 levelset方法 自由表面 溃坝波 Ns方程
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快速粒子level set方法的并行化
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作者 黄筱云 夏波 +1 位作者 程永舟 赵利平 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2018年第9期1478-1484,共7页
为缩短快速粒子level set(FPLS)方法追踪交界面的时间,分别运用区域分解和粒子分解算法来减少欧拉计算(level set对流方程和重新初始化)和拉格朗日计算(粒子时程积分和误差校正)的开销。算法采用OpenMP技术来实现,并通过Zalesak圆盘、... 为缩短快速粒子level set(FPLS)方法追踪交界面的时间,分别运用区域分解和粒子分解算法来减少欧拉计算(level set对流方程和重新初始化)和拉格朗日计算(粒子时程积分和误差校正)的开销。算法采用OpenMP技术来实现,并通过Zalesak圆盘、单涡以及三维变形等典型算例进行验证。计算结果表明:4线程下加速比能超过2,8线程下加速比也能接近4,并行化的FPLS方法具有良好的实用性和可扩展性。 展开更多
关键词 快速粒子level sET方法 并行 区域分解 粒子分解 OPENMP Zalesak圆盘 单涡
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Nucleoside diphosphate-linked moiety X-type motif 15 R139C genotypes impact 6-thioguanine nucleotide cut-off levels to predict thiopurine-induced leukopenia in Crohn’s disease patients 被引量:4
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作者 Xia Zhu Kang Chao +7 位作者 Miao Li Wen Xie Hong Zheng Jin-Xin Zhang Pin-Jin Hu Min Huang Xiang Gao Xue-Ding Wang 《World Journal of Gastroenterology》 SCIE CAS 2019年第38期5850-5861,共12页
BACKGROUND Thiopurine-induced leukopenia(TIL)is a life-threatening toxicity and occurs with a high frequency in the Asian population.Although nucleoside diphosphate-linked moiety X-type motif 15(NUDT15)variants signif... BACKGROUND Thiopurine-induced leukopenia(TIL)is a life-threatening toxicity and occurs with a high frequency in the Asian population.Although nucleoside diphosphate-linked moiety X-type motif 15(NUDT15)variants significantly improve the predictive sensitivity of TIL,more than 50%of cases of this toxicity cannot be predicted by this mutation.The potential use of the 6-thioguanine nucleotide(6TGN)level to predict TIL has been explored,but no decisive conclusion has been reached.Can we increase the predictive sensitivity based on 6TGN by subgrouping patients according to their NUDT15 R139C genotypes?AIM To determine the 6TGN cut-off levels after dividing patients into subgroups according to their NUDT15 R139C genotypes.METHODS Patients’clinical and epidemiological characteristics were collected from medical records from July 2014 to February 2017.NUDT15 R139C,thiopurine S methyltransferase,and 6TGN concentrations were measured.RESULTS A total of 411 Crohn’s disease patients were included.TIL was observed in 72 individuals with a median 6TGN level of 323.4 pmol/8×10^8 red blood cells(RBC),which was not different from that of patients without TIL(P=0.071).Then,we compared the 6TGN levels based on NUDT15 R139C.For CC(n=342)and CT(n=65)genotypes,the median 6TGN level in patients with TIL was significantly higher than that in patients without(474.8 vs 306.0 pmol/8×10^8 RBC,P=9.4×10-^5;291.7 vs 217.6 pmol/8×10^8 RBC,P=0.039,respectively).The four TT carriers developed TIL,with a median 6TGN concentration of 135.8 pmol/8×10^8 RBC.The 6TGN cut-off levels were 411.5 and 319.2 pmol/8×108 RBC for the CC and CT groups,respectively.CONCLUSION The predictive sensitivity of TIL based on 6TGN is dramatically increased after subgrouping according to NUDT15 R139C genotypes.Applying 6TGN cut-off levels to adjust thiopurine therapies based on NUDT15 is strongly recommended. 展开更多
关键词 Crohn’s disease Thioguanine NUCLEOTIDE levels NUCLEOsIDE diphosphatelinked MOIETY X-type MOTIF 15 Thiopurine-induced LEUKOPENIA
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RELATIVE SEA LEVEL RISE AND ITS EFFECTS ON ENVIRONMENT AND RESOURCES IN CHINAS COASTAL AREAS 被引量:2
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作者 杨桂山 《Chinese Geographical Science》 SCIE CSCD 1995年第2期104-115,共12页
Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21... Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21st century. It will result in a series of adverse impacts on evolution of natural environment and socioeconomic development of the coastal area. This paper analyses environmental and resource effects induced by relative sea level rise in China's coastal areas on the basis of rough estimate of future relative sea level rise. These effects include inundating tidal flat and wetlands and increase in inundated risk of coastal habitable land,exacerbating storm surge. coastal erosion, flooding and salt water intrusion hazards.as well as endangering land. water. tourism and living resources and their utilization. 展开更多
关键词 China’s COAsTAL areas. RELATIVE sEA level RIsE environmental effect resource effect
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Atomic level deposition to extend Moore’s law and beyond 被引量:9
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作者 Rong Chen Yi-Cheng Li +2 位作者 Jia-Ming Cai Kun Cao Han-Bo-Ram Lee 《International Journal of Extreme Manufacturing》 2020年第2期29-52,共24页
In the past decades,Moore’s law drives the semiconductor industry to continuously shrink the critical size of transistors down to 7 nm.As transistors further downscaling to smaller sizes,the law reaches its limitatio... In the past decades,Moore’s law drives the semiconductor industry to continuously shrink the critical size of transistors down to 7 nm.As transistors further downscaling to smaller sizes,the law reaches its limitation,and the increase of transistors density on the chip decelerates.Up to now,extreme ultraviolet lithography has been used in some key steps,and it is facing alignment precision and high costs for high-volume manufacturing.Meanwhile,the introduction of new materials and 3D complex structures brings serious challenges for top-down methods.Thus,bottom-up schemes are believed to be necessary methods combined with the top-down processes.In this article,atomic level deposition methods are reviewed and categorized to extend Moore’s law and beyond.Firstly,the deposition brings lateral angstrom resolution to the vertical direction as well as top-down etching,such as double patterning,transfer of nanowires,deposition of nanotubes,and so on.Secondly,various template-assisted selective deposition methods including dielectric templates,inhibitors and correction steps have been utilized for the alignment of 3D complex structures.Higher resolution can be achieved by inherently selective deposition,and the underlying selective mechanism is discussed.Finally,the requirements for higher precision and efficiency manufacturing are also discussed,including the equipment,integration processes,scale-up issues,etc.The article reviews low dimensional manufacturing and integration of 3D complex structures for the extension of Moore’s law in semiconductor fields,and emerging fields including but not limited to energy,catalysis,sensor and biomedicals. 展开更多
关键词 Moore’s law atomic level deposition high resolution selective deposition ALIGNMENT
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Level Set方法在自由面流动数值模拟中的应用 被引量:1
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作者 高玉丽 刘全辉 《烟台师范学院学报(自然科学版)》 2005年第1期14-16,共3页
采用建立在固定的交错网格上隐式追踪界面的LevelSet方法来计算有自由面的流动问题.在计算中求解了两种互不相溶流体的N S方程.所参考的算例是瞬时溃坝问题,计算结果和实验观测基本符合,表明Lev elSet方法在液体自由面数值模拟中具有一... 采用建立在固定的交错网格上隐式追踪界面的LevelSet方法来计算有自由面的流动问题.在计算中求解了两种互不相溶流体的N S方程.所参考的算例是瞬时溃坝问题,计算结果和实验观测基本符合,表明Lev elSet方法在液体自由面数值模拟中具有一定的适用性. 展开更多
关键词 level sET方法 自由面 N-s方程 投影法 三次插值拟粒子方法
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Infliximab trough level combined with inflammatory biomarkers predict long-term endoscopic outcomes in Crohn’s disease under infliximab therapy 被引量:1
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作者 Wan-Ting Cao Rong Huang +4 位作者 Shan Liu Yi-Hong Fan Mao-Sheng Xu Yi Xu Hui Ni 《World Journal of Gastroenterology》 SCIE CAS 2022年第23期2582-2596,共15页
BACKGROUND Infliximab trough level(ITL)severely affects therapeutic outcomes of Crohn’s disease(CD)patients under infliximab(IFX).Recently,frontier research has focused on identifying ITL based on different therapeut... BACKGROUND Infliximab trough level(ITL)severely affects therapeutic outcomes of Crohn’s disease(CD)patients under infliximab(IFX).Recently,frontier research has focused on identifying ITL based on different therapeutic targets.Although previous studies have elaborated clinical value of ITL monitoring on short-term outcomes in CD patients during therapy,studies contraposing the predictive value of ITL on long-term endoscopic outcomes in CD patients are still scarce domestically and overseas.AIM To explore the predictive value of ITL in combination with inflammatory biomarkers on long-term endoscopic outcomes in CD with clinical remission during IFX maintenance therapy.METHODS CD patients with endoscopic remission under long-term IFX maintenance therapy in the First Affiliated Hospital of Zhejiang Chinese Medicine University from January 2012 to December 2020 were collected.ITL and inflammatory biomarkers were continuously monitored during the therapy.The Step I study was conducted from weeks 14 to 54 of IFX treatment.The Step II study was conducted from weeks 54 to 108 of IFX treatment.Endoscopic outcomes were defined as endoscopic activity(Crohn’s disease endoscopic index of severity score>2 points or Rutgeerts score>i1)and endoscopic remission(Crohn’s disease endoscopic index of severity score≤2 points or Rutgeerts≤i1).Endoscopic relapse free survival was defined as endoscopic remission at the beginning of the study stage and maintaining endoscopic remission during the study stage.RESULTS At week 14,low ITL[odds ratio(OR)=0.666,95%confidence interval(CI):0.514-0.862,P<0.01]and high fecal calprotectin(FCP)level(OR=1.002,95%CI:1.001-1.004,P<0.01)increased the risk of endoscopic activity at week 54.At week 54,low ITL(OR=0.466,95%CI:0.247-0.877,P<0.01)and high C-reactive protein(CRP)level(OR=1.590,95%CI:1.007-2.510,P<0.01)increased the risk of endoscopic activity at week 108.At week 14,ITL≤5.60μg/mL[area under the curve(AUC)=0.83,95%CI:0.73-0.90,P<0.001]and FCP>238μg/g(AUC=0.82,95%CI:0.72-0.89,P<0.001)moderately predicted endoscopic activity at week 54.ITL≤5.60μg/mL in combination with FCP>238μg/g indicated 82.0%possibility of endoscopic activity.At week 54,ITL≤2.10μg/mL(AUC=0.85,95%CI:0.72-0.93,P<0.001)and CRP>3.00 mg/L(AUC=0.73,95%CI:0.60-0.84,P=0.012)moderately predicted moderate endoscopic activity at week 108.ITL≤2.10μg/mL in combination with CRP>3.00 mg/L indicated 100.0%possibility of endoscopic activity.From weeks 14 to 54 of IFX treatment,patients with ITL>5.60μg/mL had higher rate of endoscopic relapse free survival than those with ITL≤5.60μg/mL(95.83%vs 46.67%).From weeks 54 to 108 of IFX treatment,patients with ITL>2.10μg/mL had higher rate of endoscopic survival free relapsed rate than those with ITL≤2.10μg/mL(92.68%vs 30.77%).CONCLUSION Combination of ITL,CRP,and FCP contribute to long-term endoscopic prognosis monitoring.During IFX maintenance treatment,low ITL,high CRP level,and high FCP level were independent risk factors of CD patients with clinical remission in adverse endoscopy outcomes within 1-year follow-up. 展开更多
关键词 Infliximab trough level C-reactive protein Fecal calprotectin Crohn’s disease Clinical remission Long-term endoscopic outcomes
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The Quantum Condition That Should Have Been Assumed by Bohr When Deriving the Energy Levels of a Hydrogen Atom 被引量:2
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作者 Koshun Suto 《Journal of Applied Mathematics and Physics》 2021年第6期1230-1244,共15页
Bohr assumed a quantum condition when deriving the energy levels of a hydrogen atom. This famous quantum condition was not derived logically, but it beautifully explained the energy levels of the hydrogen atom. Theref... Bohr assumed a quantum condition when deriving the energy levels of a hydrogen atom. This famous quantum condition was not derived logically, but it beautifully explained the energy levels of the hydrogen atom. Therefore, Bohr’s quantum condition was accepted by physicists. However, the energy levels predicted by the eventually completed quantum mechanics do not match perfectly with the predictions of Bohr. For this reason, it cannot be said that Bohr’s quantum condition is a perfectly correct assumption. Since the mass of an electron which moves inside a hydrogen atom varies, Bohr’s quantum condition must be revised. However, the newly derived relativistic quantum condition is too complex to be assumed at the beginning. The velocity of an electron in a hydrogen atom is known as the Bohr velocity. This velocity can be derived from the formula for energy levels derived by Bohr. The velocity <em>v </em>of an electron including the principal quantum number <em>n</em> is given by <em>αc</em>/<em>n</em>. This paper elucidates the fact that this formula is built into Bohr’s quantum condition. It is also concluded in this paper that it is precisely this velocity formula that is the quantum condition that should have been assumed in the first place by Bohr. From Bohr’s quantum condition, it is impossible to derive the relativistic energy levels of a hydrogen atom, but they can be derived from the new quantum condition. This paper proposes raising the status of the previously-known Bohr velocity formula. 展开更多
关键词 Relativistic Energy levels of the Hydrogen Atom Bohr’s Quantum Condition Bohr Velocity Einstein’s Energy-Momentum Relationship suto’s Energy-Momentum Relationship Relativistic Kinetic Energy
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Topology and Shape Optimization of 2-D and 3-D Micro-ArchitecturedThermoelastic Metamaterials Using a Parametric Level Set Method 被引量:1
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作者 Ellie Vineyard Xin-Lin Gao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第6期819-854,共36页
2-D and 3-D micro-architectured multiphase thermoelastic metamaterials are designed and analyzed using a parametric level set method for topology optimization and the finite element method.An asymptotic homogenization... 2-D and 3-D micro-architectured multiphase thermoelastic metamaterials are designed and analyzed using a parametric level set method for topology optimization and the finite element method.An asymptotic homogenization approach is employed to obtain the effective thermoelastic properties of the multiphase metamaterials.Theε-constraint multi-objective optimization method is adopted in the formulation.The coefficient of thermal expansion(CTE)and Poisson’s ratio(PR)are chosen as two objective functions,with the CTE optimized and the PR treated as a constraint.The optimization problems are solved by using the method of moving asymptotes.Effective isotropic and anisotropic CTEs and stiffness constants are obtained for the topologically optimized metamaterials with prescribed values of PR under the constraints of specified effective bulk modulus,volume fractions and material symmetry.Two solid materials along with one additional void phase are involved in each of the 2-D and 3-D optimal design examples.The numerical results reveal that the newly proposed approach can integrate shape and topology optimizations and lead to optimal microstructures with distinct topological boundaries.The current method can topologically optimize metamaterials with a positive,negative or zero CTE and a positive,negative or zero Poisson’s ratio. 展开更多
关键词 Topology optimization thermoelastic metamaterial level set method sensitivity analysis Poisson’s ratio coefficient of thermal expansion effective elastic properties
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Evidences of the expanding Earth from space-geodetic data over solid land and sea level rise in recent two decades 被引量:2
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作者 Shen Wenbin Shen Ziyu +1 位作者 Sun Rong Barkin Yuri 《Geodesy and Geodynamics》 2015年第4期248-252,共5页
According to the space-geodetic data recorded at globally distributed stations over solid land spanning a period of more than 20-years under the International Terrestrial Reference Frame 2008,our previous estimate of ... According to the space-geodetic data recorded at globally distributed stations over solid land spanning a period of more than 20-years under the International Terrestrial Reference Frame 2008,our previous estimate of the average-weighted vertical variation of the Earth's solid surface suggests that the Earth's solid part is expanding at a rate of 0.24 ± 0.05 mm/a in recent two decades.In another aspect,the satellite altimetry observations spanning recent two decades demonstrate the sea level rise(SLR) rate 3.2 ± 0.4 mm/a,of which1.8 ± 0.5 mm/a is contributed by the ice melting over land.This study shows that the oceanic thermal expansion is 1.0 ± 0.1 mm/a due to the temperature increase in recent half century,which coincides with the estimate provided by previous authors.The SLR observation by altimetry is not balanced by the ice melting and thermal expansion,which is an open problem before this study.However,in this study we infer that the oceanic part of the Earth is expanding at a rate about 0.4 mm/a.Combining the expansion rates of land part and oceanic part,we conclude that the Earth is expanding at a rate of 0.35 ± 0.47 mm/a in recent two decades.If the Earth expands at this rate,then the altimetry-observed SLR can be well explained. 展开更多
关键词 ITRF2008 coordinates Ice melting Thermal expansion Earth expansion sea level rise sLR)space-geodetic data Velocities altimetry Earth's solid surface
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A Study of the Driving Force Model Revealing Changes in Land Utilization Level Based on 3S Technologies ——The Example of Yuanmou, Yunnan, China
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作者 HEJin-feng CHENGuo-jie YANGZhong 《Wuhan University Journal of Natural Sciences》 CAS 2005年第4期791-795,共5页
This paper introduced the theory and approaches of building driving forcemodels revealing the changes in land utilization level by integrating RS, GPS, and GIS technologiesbased on the example of Yuanmou County of Yun... This paper introduced the theory and approaches of building driving forcemodels revealing the changes in land utilization level by integrating RS, GPS, and GIS technologiesbased on the example of Yuanmou County of Yunnan Province. We first created the land utilizationtype database, natural driving forces for land utilization database, and human driving forces forland utilization database. Then we obtained the dependent and the independent variables of changesin land utilization level by exploring various data. Lastly we screened major factors affectingchanges in land utilization level by using the powerful spatial correlation analysis and maincomponent analysis module of GIS and obtained a multivariable linear regression model of thechangesin land utilization level by using GIS spatial regression analysis module. 展开更多
关键词 land utilization level driving forces data exploration 3s
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Mediterranean Sea level trends from long-period tide gauge time series
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作者 Haddad Mahdi Taibi Hebib 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第1期157-165,共9页
The main purpose of this study is to highlight, on the basis of statistical tests, the significant long-term changes of the Mediterranean Sea level, through the analysis of historical tide gauge records. In this frame... The main purpose of this study is to highlight, on the basis of statistical tests, the significant long-term changes of the Mediterranean Sea level, through the analysis of historical tide gauge records. In this framework, 14 tide gauge monthly series selected from the Permanent Service of the Mean Sea Level(PSMSL) database were used. The search for the presence or not of trends within these series, that have a temporal coverage from 59 to 142 years, was carried out using the Mann-Kendall test and the Sen’s slope estimator. The obtained results show that the Split Rt Marjana series are the only ones which does not exhibit a significant trend. The other 13 series show significant increasing trends. This result seems sufficient to suppose the presence, in the past century, of a new climatic phase on the scale of the Mediterranean basin, where the rising sea level is one of the consequences. 展开更多
关键词 sea level tidal heights trend analysis Mann-Kendall test sen’s slope estimates
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Effects of Physical Activity Levels on Fatigue Perception in Patients with Parkinson’s Disease and Neurologically Healthy Individuals
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作者 Paulo Cezar Rocha dos Santos Fabio Augusto Barbieri +2 位作者 Diego Orcioli-Silva Lucas Simieli Lilian Teresa Bucken Gobbi 《Health》 2014年第21期2927-2933,共7页
Background: Recent researches involving fatigue and Parkinson’s disease (PD) sought to verify its incidence and the impacts of fatigue on quality life of patients with PD. Despite the importance of regular physical a... Background: Recent researches involving fatigue and Parkinson’s disease (PD) sought to verify its incidence and the impacts of fatigue on quality life of patients with PD. Despite the importance of regular physical activity practice, there are only few studies that verified the influence of the levels of physical activity on fatigue in patients with PD. Objective: The aim of this study was to compare perception of fatigue between individuals with PD and neurologically healthy individuals (control group), considering the physical activity levels;and to verify the relation between physical activity levels and fatigue dimensions for individuals with PD and control group. Methods: Eighty individuals (40 patients with PD and 40 control individuals) participated in this study. Physical activity levels were evaluated through Modified Baecke Questionnaire for Older Adults. Multidimensional Fatigue Inventory (MFI) was used in order to evaluate fatigue dimensions (general, physical and mental fatigue, reduced motivation and activity). MANOVA two-way and Pearson linear correlation test were performed to analyze the data. Results: Patients with PD presented higher levels of fatigue, in all dimensions evaluated by MFI, comparing to control individuals. There was no association between physical activity levels and perception of fatigue for patients with PD and control individuals. Conclusion: Patients with PD showed increased perception of fatigue when compared to control individuals, due to PD characteristics. In addition, the perception of fatigue’s symptom was not influenced and had no relation by the level of physical activity. 展开更多
关键词 Parkinson’s Disease sYMPTOM of FATIGUE Physical Activity levels NON-MOTOR sYMPTOM
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Algebraic Study of the Vibrational Levels and Potential Energy Surface of the Excited Electronic State (C^1A') for S2O
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作者 Xiao-yan Wang Shi-liang Ding +2 位作者 Jin-dong Xie Peng-cheng Wang Wei-gang Zhong 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第1期43-46,共4页
The vibrational levels and potential energy surface of a stable structure for S2O in the excited electronic states C^1A' were carried out with algebraic method. The vibrational spectra were obtained (with total quan... The vibrational levels and potential energy surface of a stable structure for S2O in the excited electronic states C^1A' were carried out with algebraic method. The vibrational spectra were obtained (with total quantum number v=20) by fitting 30 spectra data. The fitted rms(root mean square) error based on the Hamiltonian witb 9 parameters was 2.40 cm^-1. The dissociation energy and force constant were also determined by the analytical potential energy surface. The method is proved to be effective by comparing these results with the experimental data. 展开更多
关键词 s2O3 Energy level Potential energy surface
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利用Level-Set函数求解的含表面张力项的N-S方程
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作者 高玉丽 《莱阳农学院学报》 2003年第2期125-127,共3页
流体的温度或组成的变化,都会引起表面张力的变化。因而在研究有关自由面的流体运动中,都要考虑自由面上的表面张力。本文利用当前流行的求解自由面的LevelSet方法给出含表面张力的N-S方程的推导。
关键词 表面张力 自由面 流体运动 level-set函数 N-s方程 曲率
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Filipin Levels as Potential Predictors of Alzheimer’s Disease Risk
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作者 Michael A. Castello Kristy D. Howard +1 位作者 Arthur J. Castaneda Salvador Soriano 《Advances in Alzheimer's Disease》 2014年第3期137-144,共8页
To date, therapies to prevent or treat Alzheimer’s disease (AD) have largely focused on removing excess aggregation-prone amyloid peptide Aβ from the brain, an approach that has produced disappointing clinical outco... To date, therapies to prevent or treat Alzheimer’s disease (AD) have largely focused on removing excess aggregation-prone amyloid peptide Aβ from the brain, an approach that has produced disappointing clinical outcomes. An alternative hypothesis proposes that Aβ production and aggregation is a symptom of a larger, systemic disease affecting the regulation of lipids, including cholesterol. In this scenario, lipid dysregulation would likely occur early in the disease process, making it an ideal target for predicting risk of mild cognitive impairment (MCI) to AD conversion. Here, we report that levels of filipin, a fluorescent polyene macrolide widely used as a diagnostic tool for diseases of lipid dysregulation, correlate with cellular damage caused by 27-hydroxycholesterol and with dementia status in human peripheral blood cells. These results provide strong preliminary data suggesting that filipin could be of use in the development of a quick and inexpensive method to measure the risk of AD conversion in patients with MCI, supplementing existing testing strategies that focus on the consequences of Aβ accumulation. 展开更多
关键词 Alzheimer’s Disease Lipid DYsREGULATION CHOLEsTEROL Mild Cognitive IMPAIRMENT FILIPIN levels
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A proposed classification of the Earth’s crustal areas by the level of geodynamic threat
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作者 Andrian Batugin 《Geodesy and Geodynamics》 CSCD 2021年第1期21-30,共10页
It is accepted as a well-known fact that in different places on the Earth’s crust,a similar anthropogenic impact causes a dissimilar response.Seismic zoning maps are not designed to predict such geodynamic hazards as... It is accepted as a well-known fact that in different places on the Earth’s crust,a similar anthropogenic impact causes a dissimilar response.Seismic zoning maps are not designed to predict such geodynamic hazards as rock bursts,induced earthquakes,reactivation of tectonic faults,etc.,and therefore require careful adjustments in places of intense impact on the subsurface strata.In this regard,we consider the classification of the Earth’s crustal areas according to the degree of geodynamic hazard,i.e.its potential geodynamic response to anthropogenic intervention.This classification is based on the concept that there exists a critically stressed layer within the Earth’s crust.It is believed that such a critically stressed layer within the Earth’s crust extends from the Earth’s surface to a certain depth,and each point depends on the nature of the interaction between crustal blocks of different hierarchical levels.From this perspective,anthropogenic impact,such as mining operations,represents a direct impact upon the critically stressed zone.We recognize the hypothesis that the thicker the critical stressed rock layer,the stronger the response might be to anthropogenic intervention,as it has more accumulated energy.Four categories of geodynamic threat have been found and mapped.To verify this classification,the manifestations of the geodynamic hazards were studied.The intensity of geodynamic hazard increased from the first area to the fourth area.The phenomenon of large induced seismic events with hypocenters at great depths is explained on the basis of this theory,and could be associated with anthropogenic impacts from the surface directly on the regional zone of the critically stressed rock massif.The approach can be used to assess the geodynamic consequences of human exposure to the Earth’s crust. 展开更多
关键词 Earth’s crust Critically stressed state Rock burst Induced earthquake Hypocenter depth Focal zone size level of geodynamic threat
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