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Reliability Topology Optimization Based on Kriging-Assisted Level Set Function and Novel Dynamic Hybrid Particle Swarm Optimization Algorithm
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作者 Hang Zhou Xiaojun Ding +1 位作者 Song Chen Qijun Zhang 《Computer Modeling in Engineering & Sciences》 2025年第8期1907-1933,共27页
Structural Reliability-Based Topology Optimization(RBTO),as an efficient design methodology,serves as a crucial means to ensure the development ofmodern engineering structures towards high performance,long service lif... Structural Reliability-Based Topology Optimization(RBTO),as an efficient design methodology,serves as a crucial means to ensure the development ofmodern engineering structures towards high performance,long service life,and high reliability.However,in practical design processes,topology optimization must not only account for the static performance of structures but also consider the impacts of various responses and uncertainties under complex dynamic conditions,which traditional methods often struggle accommodate.Therefore,this study proposes an RBTO framework based on a Kriging-assisted level set function and a novel Dynamic Hybrid Particle Swarm Optimization(DHPSO)algorithm.By leveraging the Kriging model as a surrogate,the high cost associated with repeatedly running finite element analysis processes is reduced,addressing the issue of minimizing structural compliance.Meanwhile,the DHPSO algorithm enables a better balance between the population’s developmental and exploratory capabilities,significantly accelerating convergence speed and enhancing global convergence performance.Finally,the proposed method is validated through three different structural examples,demonstrating its superior performance.Observed that the computational that,compared to the traditional Solid Isotropic Material with Penalization(SIMP)method,the proposed approach reduces the upper bound of structural compliance by approximately 30%.Additionally,the optimized results exhibit clear material interfaces without grayscale elements,and the stress concentration factor is reduced by approximately 42%.Consequently,the computational results fromdifferent examples verify the effectiveness and superiority of this study across various fields,achieving the goal of providing more precise optimization results within a shorter timeframe. 展开更多
关键词 Reliability topology optimization kriging model level set function dynamic hybrid particle swarm optimization engineering structure
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Algae functional group characteristics in reservoirs and lakes with different trophic levels in northwestern semi-humid and semi-arid regions in China 被引量:7
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作者 Jinsuo Lu Zhe Yang Ying Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第2期166-173,共8页
In order to study the differences in algae species and their biomass in water bodies in a region, three reservoirs and two lakes at the center of Guanzhong Plain were chosen to identify algae functional groups, measur... In order to study the differences in algae species and their biomass in water bodies in a region, three reservoirs and two lakes at the center of Guanzhong Plain were chosen to identify algae functional groups, measure biomass, and assess water quality, from January2013 to December 2014. The water bodies represented different trophic levels: one oligotrophic, three mesotrophic, and one eutrophic. Based on the Reynolds’ functional groups, they had 10 groups in common—B, P, D, X1, M, MP, F, S1, J, and G, but the algae biomasses and proportions were different. In the oligotrophic reservoir, functional group B reached a peak biomass of 576 × 104 L-1, which accounted for 31.27%. In the eutrophic lake,functional group D reached a peak biomass of 3227 × 104 L-1, which accounted for only13.38%. When samples collected from other water bodies with similar trophic levels were compared, we found differences in the algae species functional groups. The potential reasons for the differences in algae functional group characteristics in the different water bodies in the region were water temperature and nutritional states. 展开更多
关键词 functional group classifications Lakes and reservoirs Trophic levels functional group characteristics
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Effect of Intermittent Pneumatic Compression on Functional Level and Quality of Life in Community-Dwelling Older Adults with Limited Ambulation Due to Leg Pain: A Randomized Controlled Trial
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作者 Weerasinghe Mudiyanselage Sujeewa Weerasinghe Thunpaththu Mudiyanselage Upul Sanjeewa Thunpaththu +4 位作者 Weerasinghe Mudiyanselage Sandali Anjana Weerasinghe Weerasinghe Mudiyanselage Shalindu Thushen Weerasinghe Pahala Walpola Gamarallage Shirani Walpola Dissanayaka Mudiyanselage Tharanga Padmini Dissanayaka Angelo Karunaratne 《Health》 2021年第10期1145-1169,共25页
Background and Purpose: Walking difficulties are defined as any reduction in speed, balance, or change of gait, causing limited ambulation. These difficulties are a common problem in older adults and may greatly affec... Background and Purpose: Walking difficulties are defined as any reduction in speed, balance, or change of gait, causing limited ambulation. These difficulties are a common problem in older adults and may greatly affect their quality of life (QOL) and restrict their personal independence and participation. This study aimed to determine the effect of intermittent pneumatic compression (IPC) on lower leg pain, walking capacity, functional mobility, ankle range of motion (AROM), and QOL of community-dwelling older people with walking difficulties. Methods: In this randomized controlled trial, 34 eligible participants with self-reported lower limb pain and limited ambulation were randomized either to the intermittent pneumatic compression intervention group (IPCIG) or static compression control group (SCCG). The IPCIG and SCCG were trained to receive IPC and SC respectively for both lower legs and instructed to continue the application independently at home for 15 minutes per session, 2 sessions a day, 7 days per week for 4 weeks independently at the home. Outcome measures of lower leg pain, AROM, walking capacity, and functional mobility were assessed at baseline and at the first, second, third, and fourth weeks after randomization. Quality of life was assessed at baseline and immediately after the intervention. Results and Discussion: IPCIG showed a more significant improvement compared to the SCCG at the post-interventional stage for QOL and all the subscales. The findings show that “80% improved QOL” is 53% higher with the application of IPC than with SC for 4 weeks. The IPCIG showed a more significant improvement in the 6-minute walk test (6 MWT) at the third and fourth weeks compared to the SCCG. A pairwise comparison of mean values of 6 MWT over 4 weeks within the IPCIG showed a significant difference between all the weeks. Pairwise comparisons between groups at each time point showed that the IPCIG showed a more significant improvement in the timed up and go (TUG) test at the third and fourth weeks compared to the SCCG. Pairwise comparison of mean values of TUG test within the IPCIG showed a significant difference over 4 weeks, except between the second and third weeks, fourth week, and third and fourth weeks. The IPCIG showed a more significant improvement in lower leg pain between all weeks except the first week compared to the SCCG. Pairwise comparison of mean values of lower leg pain over 4 weeks within the IPCIG showed a significant difference among all weekly outcomes except between 1 and 2 weeks. The IPCIG showed a more significant improvement in left and right ankle dorsiflexion ROM at the third and fourth weeks compared to the SCCG. Conclusions: The IPC was effective in reducing lower leg pain and increasing the AROM and improving the walking capacity, functional mobility level, and QOL of community-dwelling older people with walking disabilities. Walking disability in old age is a common condition requiring physical therapy. Intermittent pneumatic compression can be used as a physical therapy modality for this patient group. 展开更多
关键词 Intermittent Pneumatic Compression functional level Quality of Life Older Adults Limited Ambulation Leg Pain
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Weighted Multi-sensor Data Level Fusion Method of Vibration Signal Based on Correlation Function 被引量:7
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作者 BIN Guangfu JIANG Zhinong +1 位作者 LI Xuejun DHILLON B S 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第5期899-904,共6页
As the differences of sensor's precision and some random factors are difficult to control,the actual measurement signals are far from the target signals that affect the reliability and precision of rotating machinery... As the differences of sensor's precision and some random factors are difficult to control,the actual measurement signals are far from the target signals that affect the reliability and precision of rotating machinery fault diagnosis.The traditional signal processing methods,such as classical inference and weighted averaging algorithm usually lack dynamic adaptability that is easy for trends to cause the faults to be misjudged or left out.To enhance the measuring veracity and precision of vibration signal in rotary machine multi-sensor vibration signal fault diagnosis,a novel data level fusion approach is presented on the basis of correlation function analysis to fast determine the weighted value of multi-sensor vibration signals.The approach doesn't require knowing the prior information about sensors,and the weighted value of sensors can be confirmed depending on the correlation measure of real-time data tested in the data level fusion process.It gives greater weighted value to the greater correlation measure of sensor signals,and vice versa.The approach can effectively suppress large errors and even can still fuse data in the case of sensor failures because it takes full advantage of sensor's own-information to determine the weighted value.Moreover,it has good performance of anti-jamming due to the correlation measures between noise and effective signals are usually small.Through the simulation of typical signal collected from multi-sensors,the comparative analysis of dynamic adaptability and fault tolerance between the proposed approach and traditional weighted averaging approach is taken.Finally,the rotor dynamics and integrated fault simulator is taken as an example to verify the feasibility and advantages of the proposed approach,it is shown that the multi-sensor data level fusion based on correlation function weighted approach is better than the traditional weighted average approach with respect to fusion precision and dynamic adaptability.Meantime,the approach is adaptable and easy to use,can be applied to other areas of vibration measurement. 展开更多
关键词 vibration signal MULTI-SENSOR data level fusion correlation function weighted value
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Emotion processing in Parkinson's disease: a blood oxygenation level-dependent functional magnetic resonance imaging study 被引量:6
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作者 Mohammed Benzagmout Sa?d Boujraf +8 位作者 Badreeddine Alami Hassane Ali Amadou Halima El Hamdaoui Amine Bennani Mounir Jaafari Ismail Rammouz Mustapha Maaroufi Rabia Magoul Driss Boussaoud 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第4期666-672,共7页
Parkinson's disease is a neurodegenerative disorder caused by loss of dopamine neurons in the substantia nigra pars compacta. Tremor, rigidity, and bradykinesia are the major symptoms of the disease. These motor i... Parkinson's disease is a neurodegenerative disorder caused by loss of dopamine neurons in the substantia nigra pars compacta. Tremor, rigidity, and bradykinesia are the major symptoms of the disease. These motor impairments are often accompanied by affective and emotional dysfunctions which have been largely studied over the last decade. The aim of this study was to investigate emotional processing organization in the brain of patients with Parkinson's disease and to explore whether there are differences between recognition of different types of emotions in Parkinson's disease. We examined 18 patients with Parkinson's disease(8 men, 10 women) with no history of neurological or psychiatric comorbidities. All these patients underwent identical brain blood oxygenation level-dependent functional magnetic resonance imaging for emotion evaluation. Blood oxygenation level-dependent functional magnetic resonance imaging results revealed that the occipito-temporal cortices, insula, orbitofrontal cortex, basal ganglia, and parietal cortex which are involved in emotion processing, were activated during the functional control. Additionally, positive emotions activate larger volumes of the same anatomical entities than neutral and negative emotions. Results also revealed that Parkinson's disease associated with emotional disorders are increasingly recognized as disabling as classic motor symptoms. These findings help clinical physicians to recognize the emotional dysfunction of patients with Parkinson's disease. 展开更多
关键词 Parkinson’s disease EMOTION processing BLOOD OXYGENATION level-dependent functional magnetic resonance imaging brain activation DOPAMINE neural REGENERATION
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Nonconstant Harmonic Functions on the Level 3 Sierpinski Gasket
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作者 Donglei Tang Rui Hu 《Analysis in Theory and Applications》 2014年第4期417-424,共8页
We give a detailed description of nonconstant harmonic functions on the level 3 Sierpinski gasket. Then we extend the method onβ-set with 1/3〈β〈1/2.
关键词 Nonconstant harmonic function level 3 Sierpinski gasket β-set.
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The Single Valley Character of Level Degree Function
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作者 傅增明 佟晓石 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期153-155,共3页
Strict proof has been given to single valley character of level degree function by use of convex analysis theory, which provides reliable theoretical basis for the optimization of the data processing with respect to l... Strict proof has been given to single valley character of level degree function by use of convex analysis theory, which provides reliable theoretical basis for the optimization of the data processing with respect to level degree. As circle degree and cylindrical degree have the same mathematical structures, their single valley character can be proved by the same method. 展开更多
关键词 Convex Analysis Theory level Degree function Single Valley Character.
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Philosophy of GodForm:Power Authorities, Functional Position Levels, Religion and Science
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作者 Refet Ramiz 《Journal of Philosophy Study》 2021年第3期166-215,共50页
In this work,author expressed new R-Synthesis specifically.Good and/or correct perspective that must be behind the definitions and administration generally expressed.New perspective of the philosophy explained general... In this work,author expressed new R-Synthesis specifically.Good and/or correct perspective that must be behind the definitions and administration generally expressed.New perspective of the philosophy explained generally.Philosophy of GodForm is defined and expressed as connected/related with the following concepts:(a)basic principles,(b)17 upper constructional philosophies,(c)14 lower constructional philosophies,(d)eight basic philosophies.As special cases,Philosophy of Engineering and Technology,Philosophy of Wireless Administration and others defined as hybrid philosophies.17 specific components/units which can be considered to define the basic principles of the related formation,are proposed to be designed by GodForm and defined by the author.Philosophy of GodForm and its relation with Values and Positions specifically defined.New Era Theory and New Era Belief explained generally.Some specific religions/beliefs are defined as variants/forms of the Progressive Religion.Good and/or correct power authorities(R-Power Authority)are defined due to 29 categories.Functional position levels defined for the R-Power Authorities with a unique table.As result of the R-Synthesis,functional position levels of some philosophers,some scientists,and of Prophet Jesus,Prophet Mohamed,Prophets Mouses,Buddha,and of Confucius generally/specifically defined.Integration and past/present effects of some R-Power Authorities in 5 x 5 Ideal Political Construction specifically explained.New Era Belief,Concepts of GodX and Science relation explained with the following concepts:(1)Religion of GodForm,(2)Knowledge of GodX,(3)Nature of GodX.With this respect,some other characteristics of 7 GodX power authorities expressed with details as complementary information.Following concepts/systems defined to arrange and solve some/most/all religious problems,which are determined with R-Synthesis:(a)Religious Responsibilities and Positions,(b)Ideal Religious Administration,(c)Sustainable/Continuable Political Administration System,(d)Community Values Council/Authority for each world country,(e)Progressive Councils.15 general religious position categories defined to express their good and/or correct meanings/values/responsibilities in the religious system.21 general/specific cases/programs defined due to New Era Belief to solve possible past/present/future community values problems,to have continuous,judicious,and progressive administration about the 36 kinds of community values.Progressive Councils,which are related with the CUS-WW-HO,are defined.Progressive Religion Council and some of the related religious responsibilities expressed for the kind progressive religion studies due to the Philosophy of Progressive Religions. 展开更多
关键词 PHILOSOPHY New Era Philosophy Philosophy of GodX philosophy of religion religion and science New Era Theory New Era Belief Progressive Religions power authorities functional position levels
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Random testing for system-level functional verification of system-on-chip 被引量:4
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作者 Ma Qinsheng Cao Yang +1 位作者 Yang Jun Wang Min 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第6期1378-1383,共6页
In order to deal with the limitations during the register transfer level verification, a new functional verification method based on the random testing for the system-level of system-on-chip is proposed.The validity o... In order to deal with the limitations during the register transfer level verification, a new functional verification method based on the random testing for the system-level of system-on-chip is proposed.The validity of this method is proven theoretically.Specifically, testcases are generated according to many approaches of randomization.Moreover, the testbench for the system-level verification according to the proposed method is designed by using advanced modeling language.Therefore, under the circumstances that the testbench generates testcases quickly, the hardware/software co-simulation and co-verification can be implemented and the hardware/software partitioning planning can be evaluated easily.The comparison method is put to use in the evaluation approach of the testing validity.The evaluation result indicates that the efficiency of the partition testing is better than that of the random testing only when one or more subdomains are covered over with the area of errors, although the efficiency of the random testing is generally better than that of the partition testing.The experimental result indicates that this method has a good performance in the functional coverage and the cost of testing and can discover the functional errors as soon as possible. 展开更多
关键词 VLSI circuit VERIFICATION random process function TESTING SYSTEM-ON-CHIP system-level.
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Impact of Nonlethal Levels of Metacid-50 and Carbaryl on Thyroid Function and Cholinergic System of Channa punctatus 被引量:1
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作者 PROBODHGHOSH SAMIRBHATTACHARYA SHELLEYBHATTACHARYA 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1989年第2期92-97,共6页
With regard to brain acetylcholinesterase and acetylcholine and serum triiodothyronine(T_3) and thyroxine(T_4)profiles,a biphasic response pattern was elicited in Channa punctatus chroni- cally exposed to nonlethal do... With regard to brain acetylcholinesterase and acetylcholine and serum triiodothyronine(T_3) and thyroxine(T_4)profiles,a biphasic response pattern was elicited in Channa punctatus chroni- cally exposed to nonlethal doses of locally used pesticides,namely,Metacid-50 and Carbaryl. Data revealed that these xenobiotics caused significant inhibition of brain acetylcholinesterase activity and a decrease in thyroxine level accompanied by a concurrent increase in acetylcholine accumulation and T_3 level.It is surmised that Metacid-50 and Carbaryl influence both neural and hormonal functions.1989 Academic Press.Inc. 展开更多
关键词 In Impact of Nonlethal levels of Metacid-50 and Carbaryl on Thyroid function and Cholinergic System of Channa punctatus ACHE
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Investigation of analytical harmonic frequency and potential energy function, vibrational levels for the X^2∑^+ and A^2Л states of CN radical
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作者 Wang Jian-Kun Wu Zhen-Sen 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期2919-2924,共6页
This paper calculates the equilibrium structure and the potential energy functions of the ground state (X^2∑^+) and the low lying excited electronic state (A^2Л) of CN radical are calculated by using CASSCF met... This paper calculates the equilibrium structure and the potential energy functions of the ground state (X^2∑^+) and the low lying excited electronic state (A^2Л) of CN radical are calculated by using CASSCF method. The potential energy curves are obtained by a least square fitting to the modified Murrell-Sorbie function. On the basis of physical theory of potential energy function, harmonic frequency (ωe) and other spectroscopic constants (ωeχe, βe and αe) are calculated by employing the Rydberg-Klei-Rees method. The theoretical calculation results are in excellent agreement with the experimental and other complicated theoretical calculation data. In addition, the eigenvalues of vibrational levels have been calculated by solving the radial one-dimensional SchrSdinger equation of nuclear motion using the algebraic method based on the analytical potential energy function. 展开更多
关键词 potential energy function harmonic frequency vibrational levels algebraic method
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TWO-LEVEL METHOD FOR UNSTEADY NAVIER-STOKES EQUATIONS IN STREAM FUNCTION FORM
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作者 RenChunfeng MaYichen XuHui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第1期105-120,共16页
Two-level finite element approximation to stream function form of unsteady Navier-Stokes equations is studied.This algorithm involves solving one nonlinear system on a coarse grid and one linear problem on a fine grid... Two-level finite element approximation to stream function form of unsteady Navier-Stokes equations is studied.This algorithm involves solving one nonlinear system on a coarse grid and one linear problem on a fine grid.Moreover,the scaling between these two grid sizes is super-linear.Approximation,stability and convergence aspects of a fully discrete scheme are analyzed.At last a numrical example is given whose results show that the algorithm proposed in this paper is effcient. 展开更多
关键词 Navier-Stokes equations two-level method stream function APPROXIMATION STABILITY convergence.
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LEVEL SET METHODS BASED ON DISTANCE FUNCTION
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作者 王德军 唐云 +1 位作者 于洪川 唐泽圣 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第8期950-960,共11页
Some basic problems on the level set methods were discussed, such as the method used to preserve the distance junction , the existence and uniqueness of solution for the level set equations. The main contribution is t... Some basic problems on the level set methods were discussed, such as the method used to preserve the distance junction , the existence and uniqueness of solution for the level set equations. The main contribution is to prove that in a neighborhood of the initial zero level set, the level set equations with the restriction of the distance function have a unique solution, which must be the signed distance function with respect to the evolving surface. Some skillful approaches were used: Noticing that any solution for the original equation was a distance function, the original level set equations were transformed into a simpler alternative form. Moreover, since the new system was not a classical one, the system was transformed into an ordinary one, for which the implicit function method was adopted. 展开更多
关键词 level set methods distance function existence and uniqueness of the solution
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改良术前肠道准备对腹腔镜全子宫切除术患者胃肠功能及电解质水平的影响
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作者 王征 李素红 +3 位作者 张清伟 林宁 杨欢 张慧 《黑龙江医学》 2026年第2期169-171,共3页
目的:探讨改良术前肠道准备在腹腔镜全子宫切除术(TLH)患者中的应用效果。方法:选取2023年1—4月漯河市中心医院收治的60例行TLH患者作为研究对象,随机将其分为对照组(n=30)和观察组(n=30)。对照组采用常规术前肠道准备,观察组采用改良... 目的:探讨改良术前肠道准备在腹腔镜全子宫切除术(TLH)患者中的应用效果。方法:选取2023年1—4月漯河市中心医院收治的60例行TLH患者作为研究对象,随机将其分为对照组(n=30)和观察组(n=30)。对照组采用常规术前肠道准备,观察组采用改良术前肠道准备。对比两组患者肠道准备效果、胃肠功能、电解质水平、不良反应发生情况、护理满意度。结果:观察组患者肠道准备效果、胃肠功能恢复情况、电解质水平、护理满意度均优于对照组,差异均有统计学意义(P<0.05);观察组患者不良反应发生率低于对照组,差异有统计学意义(P<0.05)。结论:改良术前肠道准备在TLH患者中具有较好的肠道准备效果,有利于促进术后胃肠功能早期恢复,减轻电解质水平波动,稳定机体状态,还可减少不良反应的发生,患者护理满意度较高。 展开更多
关键词 腹腔镜全子宫切除术 改良术前肠道准备 胃肠功能 电解质水平
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复方丹参滴丸结合阿托伐他汀对冠心病并高脂血症疗效及血清TRAIL水平表达的影响
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作者 周云 镇海涛 李军 《中国医药指南》 2026年第3期154-156,共3页
目的探究复方丹参滴丸+阿托伐他汀方案用于冠心病并高脂血症患者的效果,以及血清TRAIL表达的影响。方法选取冠心病伴高脂血症患者84例为研究对象,均于2022年7月至2025年1月在湖北科技学院附属第二医院进行治疗,随机数字表法分组,每组42... 目的探究复方丹参滴丸+阿托伐他汀方案用于冠心病并高脂血症患者的效果,以及血清TRAIL表达的影响。方法选取冠心病伴高脂血症患者84例为研究对象,均于2022年7月至2025年1月在湖北科技学院附属第二医院进行治疗,随机数字表法分组,每组42例,对照组为阿托伐他汀治疗,观察组则联合复方丹参滴丸治疗,比较两组心功能、血脂水平、肿瘤坏死因子α(TNF-α)、肿瘤坏死因子相关凋亡诱导配体(TRAIL)及疗效。结果经治疗后,观察组心功能及血脂指标水平均优于对照组(P<0.05);观察组TNF-α、TRAIL均低于对照组(P<0.05);疗效分析,观察组(95.24%)与对照组(76.19%)比较更高(P<0.05)。结论通过中西医联合治疗可有效改善冠心病合并高脂血症患者心功能,降低其血脂状态,且可促使外周血TRAIL水平下调,进一步提高治疗效果,对患者预后改善有重要意义。 展开更多
关键词 冠心病 高脂血症 复方丹参滴丸 阿托伐他汀 疗效 心功能 血脂水平
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凝胶体系中的凝聚态化学:从制备和结构到物理化学性质与材料应用
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作者 李豹 刘梦杰 吴立新 《化学进展》 北大核心 2026年第1期151-162,共12页
凝聚态化学具有丰富的内涵概念和广泛的外延空间,能为化学学科多个领域的理解和认识提供全新的视角和思路。虽然凝聚态化学在固态和液态体系中的应用已经得到一定的阐述,但其在更多化学相关研究领域及物质状态的拓展仍有待进一步加强。... 凝聚态化学具有丰富的内涵概念和广泛的外延空间,能为化学学科多个领域的理解和认识提供全新的视角和思路。虽然凝聚态化学在固态和液态体系中的应用已经得到一定的阐述,但其在更多化学相关研究领域及物质状态的拓展仍有待进一步加强。凝胶作为一类介于液态和固态之间的物质,具有多层次网络结构、丰富的物理化学性质以及广泛的应用前景,是凝聚态化学研究的理想候选体系。本文从凝聚态化学角度出发,通过对凝胶体系中基本概念和研究内容展开探究,系统阐述和说明凝胶体系中的凝聚态化学问题以及二者的相互印证关系。具体内容包括凝聚态化学思想在凝胶制备策略中的灵活运用以及由此产生的结构变化、凝胶从微观的原子、分子排列,到介观的纳米尺度结构,再到宏观的材料整体构型的多层次结构及相互之间的关系、凝胶研究中的表征方法与技术及其与凝胶结构之间的关系、利用凝聚态化学的思想理解凝胶的物理化学性质及凝胶体系中化学反应的途径和机制、凝胶材料的结构与性能的关系以及复杂体系中各组分之间的相互作用、凝胶材料在组织工程、药物递送、人机接口和环境领域的典型应用。通过对以上方面内容的阐述和总结,将加深凝聚态化学在凝胶体系中应用的理解,并为高效凝胶材料的设计与优化提供理论支撑。 展开更多
关键词 凝聚态化学 凝胶 多层次网络结构 功能材料
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新时期国土空间综合治理的理论框架与科学议题——基于统筹发展与安全的视角
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作者 周侃 樊杰 +7 位作者 徐勇 李平星 王强 刘汉初 陶岸君 孙勇 张健 魏佳荣 《资源科学》 北大核心 2026年第1期1-13,共13页
面向新时期国土空间治理中非线性风险增强与人地系统复杂性凸显的双重挑战,本文融合人文地理学的地域功能理论、资源科学的要素流动配置分析以及生态学的生态系统服务流研究等多学科视角,构建了统筹高质量发展和高水平安全的国土空间综... 面向新时期国土空间治理中非线性风险增强与人地系统复杂性凸显的双重挑战,本文融合人文地理学的地域功能理论、资源科学的要素流动配置分析以及生态学的生态系统服务流研究等多学科视角,构建了统筹高质量发展和高水平安全的国土空间综合治理理论框架。该框架以地域功能时空优化与综合效益协调为核心,确立演进韧性增强与协同效率提升相结合的适应性治理导向,并强调通过培育新质生产力推动国土空间利用模式向创新驱动、场景融合与系统韧性并重转型。在此基础上,阐释了生态价值实现机制、资源要素优化配置、空间韧性治理、绿色低碳转型路径以及全周期智慧治理体系等科学议题。结合《资源科学》本期专刊《新时期国土空间综合治理理论与方法创新》相关实证研究,从微观主体行为响应、中观区域供需匹配与宏观空间形态演变3个尺度,验证了该理论框架在应对生态修复、食物系统转型、城市更新及能源结构优化等现实议题中的解释力与指导价值,旨在为构建安全、韧性、高效、绿色的中国式现代化国土空间格局提供理论依据与实践参考。 展开更多
关键词 国土空间综合治理 高质量发展 高水平安全 地域功能 空间均衡 新质生产力
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新时代对村巡察的政治功能、实践特征与运行机制
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作者 廖冲绪 孙珩 《廉政文化研究》 2026年第1期98-107,共10页
党的十八大以来,以习近平同志为核心的党中央坚持大抓基层的鲜明导向,不断推动全面从严治党向基层延伸、向纵深发展。新时代开展对村巡察作为党内监督的重要制度创新,在治理农村微腐败问题、建强村级党组织、厚植党的执政根基等方面发... 党的十八大以来,以习近平同志为核心的党中央坚持大抓基层的鲜明导向,不断推动全面从严治党向基层延伸、向纵深发展。新时代开展对村巡察作为党内监督的重要制度创新,在治理农村微腐败问题、建强村级党组织、厚植党的执政根基等方面发挥了重要作用,其政治监督、政治引领以及政治保障功能日益彰显。在实践中,对村巡察基于特定的政治场域、监督层级以及社会环境,在运行逻辑、巡察方式、监督网络和价值导向方面呈现“制度分殊”现象,基层性、灵活性、贯通性和民生性成为对村巡察区别于其他党内监督的标识性特征。随着新时代党的建设总要求的深入贯彻和国家治理现代化进程的深入推进,高质量开展对村巡察必须在责任落实、协同联动、动力激发、权力制约等机制构建方面着力,切实发挥其“利剑”作用。 展开更多
关键词 对村巡察 政治功能 实践特征 运行机制
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福建地区地震背景噪声特征分析
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作者 巫立华 张宝剑 +2 位作者 黄鹤凌 戴丽金 赵文波 《华南地震》 2026年第1期9-17,共9页
为提高福建地区背景噪声特性认识和福建预警台网观测数据质量,选取福建地震预警台网120个测震台站2023年全年连续波形数据,应用地震噪声功率谱密度(PSD)、概率密度函数(PDF)及均方根值(RMS)分析方法,评估福建地区地震噪声水平和背景噪... 为提高福建地区背景噪声特性认识和福建预警台网观测数据质量,选取福建地震预警台网120个测震台站2023年全年连续波形数据,应用地震噪声功率谱密度(PSD)、概率密度函数(PDF)及均方根值(RMS)分析方法,评估福建地区地震噪声水平和背景噪声特征。结果表明:福建预警测震台网整体噪声水平以II级为主,空间分布呈现一定区域规律,沿海人口密集、工业活动频繁区域的台站噪声水平高于中西部山区台站。噪声频谱特征分析表明:低频段(<0.1 Hz)噪声主要受温湿度扰动及气流影响,噪声PSD值在-170 dB至-130 dB之间波动,部分台站水平通道噪声明显高于垂直通道,建议加强地震计防护措施和基准面校准;中频段(0.1~1 Hz)噪声与海洋活动密切相关,其PSD值较全球最低噪声模型(NLNM)高约20 dB,且卓越频率(0.3 Hz)较全球最低噪声模型偏移0.1 Hz,冬季双频微震能量略高于夏季;高频段(>1 Hz)噪声以人文噪声为主导,昼夜变化显著,通过远离人口密集的城镇或者山洞安装可以有效地降低台站周围干扰源。 展开更多
关键词 背景噪声 噪声水平 功率谱密度 概率密度函数
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基于网函数插值的MODIS Level 1B图像Bowtie效应修正 被引量:7
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作者 宋莎莎 张杰 孟俊敏 《遥感技术与应用》 CSCD 北大核心 2010年第4期552-559,共8页
MODIS图像中Bowtie效应普遍存在,严重影响着数据的广泛应用和后续处理,因此Bowtie修正是MODIS图像处理必不可少的步骤。提出了基于网函数插值的MODIS图像Bowtie效应修正方法,其特点是利用MODIS Level 1B产品自带的地理纬度数据确定重复... MODIS图像中Bowtie效应普遍存在,严重影响着数据的广泛应用和后续处理,因此Bowtie修正是MODIS图像处理必不可少的步骤。提出了基于网函数插值的MODIS图像Bowtie效应修正方法,其特点是利用MODIS Level 1B产品自带的地理纬度数据确定重复行数。应用个例表明,基于网函数插值的方法可以有效地对Bowtie效应进行修正,并且可以避免相关系数方法计算重复行数的不稳定性问题。 展开更多
关键词 网函数插值 MODIS level 1B Bowtie效应
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