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Serum cystatin C,monocyte/high-density lipoprotein-C ratio,and uric acid for the diagnosis of coronary heart disease and heart failure 被引量:1
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作者 Ming Li Da-Hao Yuan +2 位作者 Zhi Yang Teng-Xiang Luw Xiao-Biao Zou 《World Journal of Clinical Cases》 SCIE 2024年第18期3461-3467,共7页
BACKGROUND Coronary heart disease(CHD)and heart failure(HF)are the major causes of morbidity and mortality worldwide.Early and accurate diagnoses of CHD and HF are essential for optimal management and prognosis.Howeve... BACKGROUND Coronary heart disease(CHD)and heart failure(HF)are the major causes of morbidity and mortality worldwide.Early and accurate diagnoses of CHD and HF are essential for optimal management and prognosis.However,conventional diagnostic methods such as electrocardiography,echocardiography,and cardiac biomarkers have certain limitations,such as low sensitivity,specificity,availability,and cost-effectiveness.Therefore,there is a need for simple,noninvasive,and reliable biomarkers to diagnose CHD and HF.AIM To investigate serum cystatin C(Cys-C),monocyte/high-density lipoprotein cholesterol ratio(MHR),and uric acid(UA)diagnostic values for CHD and HF.METHODS We enrolled 80 patients with suspected CHD or HF who were admitted to our hospital between July 2022 and July 2023.The patients were divided into CHD(n=20),HF(n=20),CHD+HF(n=20),and control groups(n=20).The serum levels of Cys-C,MHR,and UA were measured using immunonephelometry and an enzymatic method,respectively,and the diagnostic values for CHD and HF were evaluated using receiver operating characteristic(ROC)curve analysis.RESULTS Serum levels of Cys-C,MHR,and UA were significantly higher in the CHD,HF,and CHD+HF groups than those in the control group.The serum levels of Cys-C,MHR,and UA were significantly higher in the CHD+HF group than those in the CHD or HF group.The ROC curve analysis showed that serum Cys-C,MHR,and UA had good diagnostic performance for CHD and HF,with areas under the curve ranging from 0.78 to 0.93.The optimal cutoff values of serum Cys-C,MHR,and UA for diagnosing CHD,HF,and CHD+HF were 1.2 mg/L,0.9×10^(9),and 389μmol/L;1.4 mg/L,1.0×10^(9),and 449μmol/L;and 1.6 mg/L,1.1×10^(9),and 508μmol/L,respectively.CONCLUSION Serum Cys-C,MHR,and UA are useful biomarkers for diagnosing CHD and HF,and CHD+HF.These can provide information for decision-making and risk stratification in patients with CHD and HF. 展开更多
关键词 Serum cystatin C Monocyte/high-density lipoprotein-C ratio Uric acid Coronary heart disease Heart failure Risk stratification
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Tandem hydroalkylation and deoxygenation of lignin-derived phenolics to synthesize high-density fuels
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作者 Rui Yu Zhensheng Shen +6 位作者 Yanan Liu Chengxiang Shi Juncong Qu Lun Pan Zhenfeng Huang Xiangwen Zhan g Ji-Jun Zou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期104-109,共6页
Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels usin... Lignin is the most abundant naturally phenolic biomass,and the synthesis of high-performance renewable fuel from lignin has attracted significant attention.We propose the efficient synthesis of high-density fuels using simulated lignin cracked oil in tandem with hydroalkylation and deoxygenation reactions.First,we investigated the reaction pathway for the hydroalkylation of phenol,which competes with the hydrodeoxygenation form cyclohexane.And then,we investigated the effects of metal catalyst types,the loading amount of metallic,acid dosage,and reactant ratio on the reaction results.The phenol hydroalkylation and hydrodeoxygenation were balanced when 180℃ and 5 MPa H_(2)with the alkanes yield of 95%.By extending the substrate to other lignin-derived phenolics and simulated lignin cracked oil,we obtained the polycyclic alkane fuel with high density of 0.918 g·ml^(-1)and calorific value of41.2 MJ·L^(-1).Besides,the fuel has good low-temperature properties(viscosity of 9.3 mm^(2)·s^(-1)at 20℃ and freezing point below-55℃),which is expected to be used as jet fuel.This work provides a promising way for the easy and green production of high-density fuel directly from real lignin oil. 展开更多
关键词 high-density fuel BIOFUEL Hydrogenation ALKYLATION Lignin Phenolics
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Kinetic-Thermodynamic Promotion Engineering toward High-Density Hierarchical and Zn-Doping Activity-Enhancing ZnNiO@CF for High-Capacity Desalination
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作者 Jie Ma Siyang Xing +2 位作者 Yabo Wang Jinhu Yang Fei Yu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期35-50,共16页
Despite the promising potential of transition metal oxides(TMOs)as capacitive deionization(CDI)electrodes,the actual capacity of TMOs electrodes for sodium storage is significantly lower than the theoretical capacity,... Despite the promising potential of transition metal oxides(TMOs)as capacitive deionization(CDI)electrodes,the actual capacity of TMOs electrodes for sodium storage is significantly lower than the theoretical capacity,posing a major obstacle.Herein,we prepared the kinetically favorable Zn_(x)Ni_(1−x)O electrode in situ growth on carbon felt(Zn_(x)Ni_(1−x)O@CF)through constraining the rate of OH^(−)generation in the hydrothermal method.Zn_(x)Ni_(1−x)O@CF exhibited a high-density hierarchical nanosheet structure with three-dimensional open pores,benefitting the ion transport/electron transfer.And tuning the moderate amount of redox-inert Zn-doping can enhance surface electroactive sites,actual activity of redox-active Ni species,and lower adsorption energy,promoting the adsorption kinetic and thermodynamic of the Zn_(0.2)Ni_(0.8)O@CF.Benefitting from the kinetic-thermodynamic facilitation mechanism,Zn_(0.2)Ni_(0.8)O@CF achieved ultrahigh desalination capacity(128.9 mgNaCl g^(-1)),ultra-low energy consumption(0.164 kW h kgNaCl^(-1)),high salt removal rate(1.21 mgNaCl g^(-1) min^(-1)),and good cyclability.The thermodynamic facilitation and Na^(+)intercalation mechanism of Zn_(0.2)Ni_(0.8)O@CF are identified by the density functional theory calculations and electrochemical quartz crystal microbalance with dissipation monitoring,respectively.This research provides new insights into controlling electrochemically favorable morphology and demonstrates that Zn-doping,which is redox-inert,is essential for enhancing the electrochemical performance of CDI electrodes. 展开更多
关键词 Zinc-nickel metal oxide high-density hierarchical Capacitive deionization Zinc-doping
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Monocyte to high-density lipoprotein cholesterol ratio as a predictor of the activity of thyroid-associated ophthalmopathy
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作者 Xing-Hong Sun Xiao-Wen Zhang +5 位作者 Chen Han Xin Dou Xue-Ying He Meng-Ru Su Feng Jiang Song-Tao Yuan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第12期2276-2281,共6页
AIM:To evaluate the relationship between monocyte to high-density lipoprotein cholesterol ratio(MHR)and the disease activity of thyroid-associated ophthalmopathy(TAO).METHODS:A total of 87 patients were classified int... AIM:To evaluate the relationship between monocyte to high-density lipoprotein cholesterol ratio(MHR)and the disease activity of thyroid-associated ophthalmopathy(TAO).METHODS:A total of 87 patients were classified into two groups based on clinical activity score(CAS)scoring criteria:high CAS group(n=62,the CAS score was≥3);low CAS group(n=25,the CAS score was<3).In addition,a group of healthy people(n=114)were included to compared the MHR.Proptosis,MHR,average signal intensity ratio(SIR),average lacrimal gland(LG)-SIR,average extraocular muscles(EOM)area from 87 patients with TAO were calculated in magnetic resonance imaging(MRI),and compared between these two groups.Correlation testing was utilized to evaluate the association of parameters among the clinical variables.RESULTS:Patients in high CAS group had a higher proptosis(P=0.041)and MHR(P=0.048).Compared to the healthy group,the MHR in the TAO group was higher(P=0.001).Correlation testing declared that CAS score was strongly associated with proptosis and average SIR,and MHR was positively associated with CAS score,average SIR,and average LG-SIR.The area under the receiver operating characteristic curve(AUC)of MHR was 0.6755.CONCLUSION:MHR,a novel inflammatory biomarker,has a significant association with CAS score and MRI imaging(average SIR and LG-SIR)and it can be a new promising predictor during the active phase of TAO. 展开更多
关键词 thyroid-associated ophthalmopathy monocyte to high-density lipoprotein cholesterol ratio disease activity
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A model for fast electron-driven high-density plasma in the double-cone ignition scheme
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作者 Zhong-Yi Chen Kai-Ge Zhao Ying-Jun Li 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期322-330,共9页
A model for fast electron-driven high-density plasma is proposed to describe the effect of injected fast electrons on the temperature and inner pressure of the plasma in the fast heating process of the double-cone ign... A model for fast electron-driven high-density plasma is proposed to describe the effect of injected fast electrons on the temperature and inner pressure of the plasma in the fast heating process of the double-cone ignition(DCI)scheme.Due to the collision of the two low-density plasmas,the density and volume of the high-density plasma vary.Therefore,the ignition temperature and energy requirement of the high-density plasma vary at different moments,and the required energy for hot electrons to heat the plasma also changes.In practical experiments,the energy input of hot electrons needs to be considered.To reduce the energy input of hot electrons,the optimal moment and the shortest time for injecting hot electrons with minimum energy are analyzed.In this paper,it is proposed to inject hot electrons for a short time to heat the high-density plasma to a relatively high temperature.Then,the alpha particles with the high heating rate and PdV work heat the plasma to the ignition temperature,further reducing the energy required to inject hot electrons.The study of the injection time of fast electrons can reduce the energy requirement of fast electrons for the high-density plasma and increase the probability of successful ignition of the high-density plasma. 展开更多
关键词 fast electrons the high-density plasma alpha particles double-cone ignition scheme the optimal moment the shortest time
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Low Stress TSV Arrays for High-Density Interconnection
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作者 Binbin Jiao Jingping Qiao +8 位作者 Shiqi Jia Ruiwen Liu Xueyong Wei Shichang Yun Yanmei Kong Yuxin Ye Xiangbin Du Lihang Yu Bo Cong 《Engineering》 SCIE EI CAS CSCD 2024年第7期201-208,共8页
In three-dimensional(3D)stacking,the thermal stress of through-silicon via(TSV)has a significant influence on chip performance and reliability,and this problem is exacerbated in high-density TSV arrays.In this study,a... In three-dimensional(3D)stacking,the thermal stress of through-silicon via(TSV)has a significant influence on chip performance and reliability,and this problem is exacerbated in high-density TSV arrays.In this study,a novel hollow tungsten TSV(W-TSV)is presented and developed.The hollow structure provides space for the release of thermal stress.Simulation results showed that the hollow W-TSV structure can release 60.3%of thermal stress within the top 2 lm from the surface,and thermal stress can be decreased to less than 20 MPa in the radial area of 3 lm.The ultra-high-density(1600 TSV∙mm2)TSV array with a size of 640×512,a pitch of 25 lm,and an aspect ratio of 20.3 was fabricated,and the test results demonstrated that the proposed TSV has excellent electrical and reliability performances.The average resistance of the TSV was 1.21 X.The leakage current was 643 pA and the breakdown voltage was greater than 100 V.The resistance change is less than 2%after 100 temperature cycles from40 to 125℃.Raman spectroscopy showed that the maximum stress on the wafer surface caused by the hollow W-TSV was 31.02 MPa,which means that there was no keep-out zone(KOZ)caused by the TSV array.These results indicate that this structure has great potential for applications in large-array photodetectors and 3D integrated circuits. 展开更多
关键词 Thermal stress Through-silicon via(TSV)high-density integration
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Predictive value of intracranial high-density areas in neurological function
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作者 Zhi-Juan Lu Jin-Xing Lai +2 位作者 Jing-Ru Huang Shu-Hua Xie Zhao-Hui Lai 《World Journal of Psychiatry》 SCIE 2024年第7期1080-1086,共7页
BACKGROUND Intracranial high-density areas(HDAs)have attracted considerable attention for predicting clinical outcomes;however,whether HDAs predict worse neurological function and mental health remains controversial a... BACKGROUND Intracranial high-density areas(HDAs)have attracted considerable attention for predicting clinical outcomes;however,whether HDAs predict worse neurological function and mental health remains controversial and unclear,which requires further investigation.In this prospective study,96 patients with acute ischemic stroke(AIS)who accepted endovascular mechanical thrombectomy(EMT)were included.The enrolled patients underwent cranial computed tomography(CT)examination within 24 hours after EMT.Clinical data in terms of National Institutes of Health Stroke Scale(NIHSS),the 3-month modified Rankin Scale(mRS),self-rating depression scale(SDS),and self-rating anxiety scale(SAS)scores were collected and compared between patients with HDAs and non-HDAs and between patients with good and poor clinical prognosis.Compared to patients without HDAs,patients with HDAs presented severe neurological deficits(admission NIHSS score:18±3 vs 19±4),were more likely to have post-stroke disabilities(mRS<3:35%vs 62%),and suffered more severe depression(SDS score:58±16 vs 64±13)and anxiety disorder(SAS score:52±8 vs 59±10).Compared to patients with a good prognosis,patients with a poor prognosis presented severe neurological deficits(admission NIHSS score:17±4 vs 20±3),were more likely to have HDAs on CT images(64%vs 33%),and suffered more severe depression(SDS score:55±19 vs 65±11)and anxiety(SAS score:50±8 vs 58±12).Multivariate analysis revealed that HDAs were independent nega-tive prognostic factors.CONCLUSION In conclusion,HDAs on CT images predicted poor prognosis and severe depressive and anxiety symptoms in patients with AIS who underwent EMT. 展开更多
关键词 Acute ischemic stroke Endovascular mechanical thrombectomy high-density areas Depressive disorder Anxiety disorder
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Correlation of Helicobacter pylori infection with high-density lipoprotein cholesterol levels and pulse wave conduction velocity
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作者 Yue-Xi Li Xiao-Qin Liu +1 位作者 Yu-Han Luo Qiao-Li Wang 《Clinical Research Communications》 2024年第4期33-38,共6页
Background:Helicobacter pylori(HP)is associated with several gastrointestinal diseases,including peptic ulcer diseases and gastric cancer,and non-gastrointestinal diseases such as hypertension and Alzheimer's dise... Background:Helicobacter pylori(HP)is associated with several gastrointestinal diseases,including peptic ulcer diseases and gastric cancer,and non-gastrointestinal diseases such as hypertension and Alzheimer's disease.However,the relationship between HP and lipid metabolism and atherosclerosis remains unclear.This study aims to investigate the association between H.pylori infection and high-density lipoprotein cholesterol levels and pulse wave conduction velocity.Methods:This is a report of a cross-sectional study that collected data from 2,827 participants.The data collected included results of life questionnaires,laboratory tests,13C-urea breath test(13C-UBT),and pulse wave conduction velocity test.Based on the results of the 13C-UBT test,the subjects were divided into two groups:the HP-uninfected group(HP−)and the HP-infected group(HP+).The study compared the differences in HDL-C levels and brachial-ankle pulse wave velocity(baPWV)between the two groups.One-way regression analysis was used to identify potential factors affecting HDL-C levels in the study population.Multiple regression equations were presented to analyze whether HP infection was an independent risk factor for abnormal HDL-C metabolism in the population.Results:Univariate analysis demonstrated that high-density lipoprotein cholesterol(HDL-C)levels were significantly lower in the HP+group compared to the HP−group,with a mean difference ofβ=−18.1 mg/dl(95%CI:−19.3 to−17.0,P<0.001).After adjusting for all variables,the HDL-C levels remained lower in the HP+group compared to the HP-group,with a mean difference ofβ=−17.4 mg/dl(95%CI:−18.2 to−16.7,P<0.001).These findings suggest that H.pylori infection is independently associated with abnormal HDL-C metabolism.Additionally,brachial-ankle pulse wave velocity(baPWV)was higher in the HP+group than in the HP−group on both sides.On the right side,the baPWV was 1,713.4±231.4 cm/s in the HP+group compared to 1,542.8±237.5 cm/s in the HP−group(t=−18.30,P<0.001).On the left side,the baPWV was 1,743.7±238.8 cm/s in the HP+group compared to 1,562.8±256.3 cm/s in the HP−group(t=−18.23,P<0.001).These results indicate a significant association between H.pylori infection and increased arterial stiffness,as measured by baPWV.Conclusion:Helicobacter pylori infection is associated with a decrease in high-density lipoprotein cholesterol levels and an increase in pulse wave conduction velocity. 展开更多
关键词 Helicobacter pylori CHOLESTEROL high-density lipoprotein ATHEROSCLEROSIS
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Smart Cellulose‑Based Janus Fabrics with Switchable Liquid Transportation for Personal Moisture and Thermal Management
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作者 Jianfeng Xi Yanling Lou +5 位作者 Liucheng Meng Chao Deng Youlu Chu Zhaoyang Xu Huining Xiao Weibing Wu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期333-347,共15页
The Janus fabrics designed for personal moisture/thermal regulation have garnered significant attention for their potential to enhance human comfort.However,the development of smart and dynamic fabrics capable of mana... The Janus fabrics designed for personal moisture/thermal regulation have garnered significant attention for their potential to enhance human comfort.However,the development of smart and dynamic fabrics capable of managing personal moisture/thermal comfort in response to changing external environments remains a challenge.Herein,a smart cellulose-based Janus fabric was designed to dynamically manage personal moisture/heat.The cotton fabric was grafted with N-isopropylacrylamide to construct a temperature-stimulated transport channel.Subsequently,hydrophobic ethyl cellulose and hydrophilic cellulose nanofiber were sprayed on the bottom and top sides of the fabric to obtain wettability gradient.The fabric exhibits anti-gravity directional liquid transportation from hydrophobic side to hydrophilic side,and can dynamically and continuously control the transportation time in a wide range of 3–66 s as the temperature increases from 10 to 40℃.This smart fabric can quickly dissipate heat at high temperatures,while at low temperatures,it can slow down the heat dissipation rate and prevent the human from becoming too cold.In addition,the fabric has UV shielding and photodynamic antibacterial properties through depositing graphitic carbon nitride nanosheets on the hydrophilic side.This smart fabric offers an innovative approach to maximizing personal comfort in environments with significant temperature variations. 展开更多
关键词 Directional water transport Cotton fabric Anti-gravity directional liquid transportation Janus wettability
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Decorative Wood Fiber/High-Density Polyethylene Composite with Canvas or Polyester Fabric
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作者 Jialin Lv Rao Fu +4 位作者 Yinan Liu Xuelian Zhou Weihong Wang Pengbo Xie Tingwei Hu 《Journal of Renewable Materials》 SCIE EI 2020年第8期879-890,共12页
Wood-plastic composite is an environmentally friendly material,due to its use of recycled thermoplastics and plant fibers.However,its surface lacks attractive aesthetic qualities.In this paper,a method of decorating w... Wood-plastic composite is an environmentally friendly material,due to its use of recycled thermoplastics and plant fibers.However,its surface lacks attractive aesthetic qualities.In this paper,a method of decorating wood fiber/high-density polyethylene(WF/HDPE)without adding adhesive was explored.Canvas or polyester fabrics were selected as the surface decoration materials.The influence of hot-pressing temperature and WF/HDPE ratio on the adhesion was studied.The surface bonding strength,water resistance,and surface color were evaluated,and observation within the infrared spectrum and under scanning electron microscopy was used to analyze the bonding process.The results showed that the fabric and WF/HDPE substrate could be closely laminated together depending on the HDPE layer accumulated on the WF/HDPE surface.The molten HDPE matrix penetrates canvas more easily than polyester fabric,and the canvasveneered composite shows a greater bonding strength than does the polyester fabric-veneered composite.A higher proportion of the thermoplastic component in the substrate improved the bonding.When the hot-pressing temperature exceeded 160°C,the fabric-veneered WF/HDPE panels had greater water resistance,although the canvas fabric changed more obviously in terms of fiber shape and color,compared with the polyester fabric.For the canvas fabric,140°C–160°C was a suitable hot-pressing temperature,whereas 160°C–180°C was more suitable for polyester fabric.The proportion of the thermoplastic component in the composite should be not less than 30%to achieve adequate bonding strength. 展开更多
关键词 wood-plastic composites high-density polyethylene polyester fiber CANVAS surface decoration
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Optimization of Extrusion Process Parameters of Recycled High-Density Polyethylene-Thermoplastic Starch Composite for Fused Filament Fabrication
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作者 Grace Njeri Wamuti James Wamai Mwangi +2 位作者 Samuel Kabini Karanja Leif Micke Henning Zeidler 《Open Journal of Composite Materials》 2023年第4期69-86,共18页
High-density poly-ethylene (HDPE) is a nonbiodegradable recyclable plastic which is widely utilized in single use packaging applications. Consequently, it constitutes a significant amount of plastic waste found in lan... High-density poly-ethylene (HDPE) is a nonbiodegradable recyclable plastic which is widely utilized in single use packaging applications. Consequently, it constitutes a significant amount of plastic waste found in landfills. From literature, it has been shown that parts produced using composites of HDPE with carbohydrate-based polymers, such as thermoplastic starch (TPS), experience mechanical degradation through hydrolytic degradation process. The possible utilization of recycled-HDPE (rHDPE) and TPS composite in nonconventional manufacturing processes such as Fused filament fabrication (FFF) has however not been explored. This study explores the potential application of rHDPE and TPS composites in FFF and optimizes the extrusion process parameters used in rHDPE-TPS filament production process. Taguchi method was utilized to analyze the extrusion process. The extrusion process parameters studied were the spooling speed, extrusion speed and the extrusion temperatures. The response variable studied was the filament diameter. In this research, the maximum TPS content achieved during filament production was 40 wt%. This filament was however challenging to use in FFF printers due to frequent nozzle clogging. Printing was therefore done with filaments that contained 0 - 30 wt% TPS. The experimental results showed that the most significant parameter in extrusion process was the spooling speed, followed by extrusion speed. Extrusion temperature had the least significant influence on the filament diameter. It was observed that increase in TPS content resulted in reduced warping and increased rate of hydrolytic degradation. Mechanical properties of printed parts were investigated and the results showed that increasing TPS content resulted in reduction in tensile strength, reduction in compression strength and increase in stiffness. The findings of this research provide valuable insights to plastic recycling industries and researchers regarding the utilization of recycled HDPE and TPS composites as substitute materials in FFF. 展开更多
关键词 Additive Manufacturing (AM) Fused Filament fabrication (FFF) High Density Polyethylene (HDPE) Thermoplastic Starch (TPS) Bio-Composite
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Contrast between 2D inversion and 3D inversion based on 2D high-density resistivity data 被引量:2
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作者 冯德山 戴前伟 肖波 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第1期224-232,共9页
The 2D data processing adopted by the high-density resistivity method regards the geological structures as two degrees, which makes the results of the 2D data inversion only an approximate interpretation;the accuracy ... The 2D data processing adopted by the high-density resistivity method regards the geological structures as two degrees, which makes the results of the 2D data inversion only an approximate interpretation;the accuracy and effect can not meet the precise requirement of the inversion. Two typical models of the geological bodies were designed, and forward calculation was carried out using finite element method. The forward-modeled profiles were obtained. 1% Gaussian random error was added in the forward models and then 2D and 3D inversions using a high-density resistivity method were undertaken to realistically simulate field data and analyze the sensitivity of the 2D and 3D inversion algorithms to noise. Contrast between the 2D and 3D inversion results of least squares inversion shows that two inversion results of high-density resistivity method all can basically reflect the spatial position of an anomalous body. However, the 3D inversion can more effectively eliminate the influence of interference from Gaussian random error and better reflect the distribution of resistivity in the anomalous bodies. Overall, the 3D inversion was better than 2D inversion in terms of embodying anomalous body positions, morphology and resistivity properties. 展开更多
关键词 high-density resistivity method finite element method forward simulation least square inversion 2D inversion 3D inversion apparent resistivity
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一种面向联盟链Hyperledger Fabric的并发冲突事务优化方法
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作者 吴海博 刘辉 +1 位作者 孙毅 李俊 《计算机研究与发展》 EI CSCD 北大核心 2024年第8期2110-2126,共17页
随着区块链技术应用的普及,联盟链Hyperledger Fabric(简称Fabric)已成为知名区块链开源平台,并得到广泛关注.然而Fabric仍受困于并发事务间冲突问题,冲突发生时会引发大量无效交易上链,导致吞吐量下降,阻碍其发展.对于该问题,现有面向... 随着区块链技术应用的普及,联盟链Hyperledger Fabric(简称Fabric)已成为知名区块链开源平台,并得到广泛关注.然而Fabric仍受困于并发事务间冲突问题,冲突发生时会引发大量无效交易上链,导致吞吐量下降,阻碍其发展.对于该问题,现有面向块内冲突的方案缺乏高效的冲突检测和避免方法,同时现有研究往往忽略区块间冲突对吞吐量的不利影响.提出了一种Fabric的优化方案Fabric-HT(fabric with high throughput),从区块内和区块间2方面入手,有效降低事务间并发冲突和提高系统吞吐量.针对区块内事务冲突,提出了一种事务调度机制,根据块内冲突事务集定义了一种高效数据结构——依赖关系链,识别具有“危险结构”的事务并提前中止,合理调度事务和消除冲突;针对区块间事务冲突,将冲突事务检测提前至排序节点完成,建立以“推送-匹配”为核心的冲突事务早期避免机制.在多场景下开展大量实验,结果表明Fabric-HT在吞吐量、事务中止率、事务平均执行时间、无效事务空间占用率等方面均优于对比方案.Fabric-HT吞吐量最高可达Fabric的9.51倍,是最新优化方案FabricSharp的1.18倍;空间利用率上相比FabricSharp提升了14%.此外,Fabric-HT也表现出较好的鲁棒性和抗攻击能力. 展开更多
关键词 并发冲突 区块链 Hyperledger fabric 事务调度 冲突检测
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基于Fabric的海量交易数据上链预处理机制 被引量:1
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作者 刘颖 马玉鹏 +2 位作者 赵凡 王轶 蒋同海 《计算机工程》 CSCD 北大核心 2024年第1期39-49,共11页
Hyperledger Fabric是一种国内外广泛使用的联盟链框架,在基于Fabric技术的一些业务中具有协同组织众多、交易操作频繁、事务冲突增加等特点。Fabric采用的多版本并发控制技术能够在一定程度上解决部分交易冲突,提升系统并发性,但其机... Hyperledger Fabric是一种国内外广泛使用的联盟链框架,在基于Fabric技术的一些业务中具有协同组织众多、交易操作频繁、事务冲突增加等特点。Fabric采用的多版本并发控制技术能够在一定程度上解决部分交易冲突,提升系统并发性,但其机制不完善,会出现部分交易数据无法正常上链存储的问题。为了实现海量交易数据完整、高效、可信的上链存储,提出一种基于Fabric预言机的数据上链预处理机制。设计海量数据冲突预处理(MCPP)方法,通过检测、监听、延时提交、事务加锁、重排序缓存等方式实现主键冲突交易数据的完整上链。引入数据传输保障措施,在传输过程中利用非对称加密技术防止恶意节点伪造认证信息,确保交易数据链外处理前后的一致性。通过理论分析和实验结果表明,该机制可有效解决联盟链平台中海量交易数据上链时的并发冲突问题,当交易数据规模达到1 000和10 000时,MCPP的时效性比LMLS提高了38%和21.4%,且成功率接近100%,具有高效性和安全性,同时在无并发冲突情况下不影响Fabric系统性能。 展开更多
关键词 联盟链 Hyperledger fabric平台 预言机 海量交易数据 并发冲突 数据传输
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High-density lipoprotein and atherosclerosis: Roles of lipid transporters 被引量:10
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作者 Yoshinari Uehara Keijiro Saku 《World Journal of Cardiology》 CAS 2014年第10期1049-1059,共11页
Various previous studies have found a negative cor-relation between the risk of cardiovascular events and serum high-density lipoprotein(HDL) cholesterol levels. The reverse cholesterol transport, a pathway of choles-... Various previous studies have found a negative cor-relation between the risk of cardiovascular events and serum high-density lipoprotein(HDL) cholesterol levels. The reverse cholesterol transport, a pathway of choles-terol from peripheral tissue to liver which has several potent antiatherogenic properties. For instance, the particles of HDL mediate to transport cholesterol from cells in arterial tissues, particularly from atherosclerotic plaques, to the liver. Both ATP-binding cassette trans-porters(ABC) A1 and ABCG1 are membrane cholesterol transporters and have been implicated in mediating cholesterol effluxes from cells in the presence of HDL and apolipoprotein A-I, a major protein constituent of HDL. Previous studies demonstrated that ABCA1 and ABCG1 or the interaction between ABCA1 and ABCG1 exerted antiatherosclerotic effects. As a therapeutic approach for increasing HDL cholesterol levels, much focus has been placed on increasing HDL cholesterol levels as well as enhancing HDL biochemical functions. HDL therapies that use injections of reconstituted HDL, apoA-I mimetics, or full-length apoA-I have shown dramatic effectiveness. In particular, a novel apoA-I mi-metic peptide, Fukuoka University ApoA-I Mimetic Pep-tide, effectively removes cholesterol via specific ABCA1 and other transporters, such as ABCG1, and has an an-tiatherosclerotic effect by enhancing the biological func-tions of HDL without changing circulating HDL choles-terol levels. Thus, HDL-targeting therapy has significant atheroprotective potential, as it uses lipid transporter-targeting agents, and may prove to be a therapeutic tool for atherosclerotic cardiovascular diseases. 展开更多
关键词 ATP-BINDING CASSETTE transporter ATP-bind-ing CASSETTE A1 ATP-BINDING CASSETTE G1 Apolipopro-tein A-I high-density LIPOPROTEIN high-density lipopro-tein therapy APOA-I MIMETIC peptide Reconstitutedf high-density LIPOPROTEIN
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基于CP-ABE算法的Fabric隐私保护模型 被引量:2
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作者 王有恒 王瑞民 张建辉 《计算机工程与设计》 北大核心 2024年第4期961-966,共6页
传统区块链系统缺少对区块数据的隐私保护。结合CP-ABE(基于属性加密的密文策略)算法和IPFS(星际文件系统),提出一种可以对Fabric区块链实现访问控制的隐私保护模型CP-PPM。CP-PPM的数据所有者可以灵活设置访问控制策略。仿真结果表明,... 传统区块链系统缺少对区块数据的隐私保护。结合CP-ABE(基于属性加密的密文策略)算法和IPFS(星际文件系统),提出一种可以对Fabric区块链实现访问控制的隐私保护模型CP-PPM。CP-PPM的数据所有者可以灵活设置访问控制策略。仿真结果表明,与现有Fabric区块链系统相比,CP-PPM模型支持细粒度的访问控制,具有更强的隐私保护效果;CP-ABE算法可以安全初始化,对数据的加解密效率更高,同时增强了区块链系统的存储性能。 展开更多
关键词 CP-ABE算法 fabric区块链 CP-PPM 隐私保护 IPFS 访问控制 存储优化
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High-resolution crustal velocity imaging using ambient noise recordings from a high-density seismic array:An example from the Shangrao section of the Xinjiang basin,China 被引量:9
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作者 Gaochun Wang Xiaobo Tian +2 位作者 Lianglei Guo Jiayong Yan Qingtian Lyu 《Earthquake Science》 CSCD 2018年第5期242-251,共10页
A profile of shallow crustal velocity structure(1–2 km) may greatly enhance interpretation of the sedimentary environment and shallow tectonic deformation.Recent advances in surface wave tomography, using ambient noi... A profile of shallow crustal velocity structure(1–2 km) may greatly enhance interpretation of the sedimentary environment and shallow tectonic deformation.Recent advances in surface wave tomography, using ambient noise data recorded with high-density seismic arrays, have improved the understanding of regional crustal structure. As the interest in detailed shallow crustal structure imaging has increased, dense seismic array methods have become increasingly efficient. This study used a high-density seismic array deployed in the Xinjiang basin in southeastern China, to record seismic data, which was then processed with the ambient noise tomography method. The high-density seismic array contained 203 short-period seismometers, spaced at short intervals(~ 400 m). The array collected continuous records of ambient noise for 32 days. Data preprocessing,cross correlation calculation, and Rayleigh surface wave phase-velocity dispersion curve extraction, yielded more than 16,000 Rayleigh surface wave phase-velocity dispersion curves, which were then analyzed using the direct-inversion method. Checkerboard tests indicate that the shear wave velocity is recovered in the study area, at depths of 0–1.4 km,with a lateral image resolution of ~ 400 m. Model test results show that the seismic array effectively images a 50 m thick slab at a depth of 0–300 m, a 150 m thick anomalous body at a depth of 300–600 m, and a 400 m thick anomalous body at a depth of 0.6–1.4 km. The shear wave velocity profile reveals features very similar to those detected by a deep seismic reflection profile across the study area. This demonstrates that analysis of shallow crustal velocity structure provides high-resolution imaging of crustal features.Thus, ambient noise tomography with a high-density seismic array may play an important role in imaging shallow crustal structure. 展开更多
关键词 high-density seismic array ambient noise tomography shallow crustal structure HIGH-RESOLUTION
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Effect of low high-density lipoprotein levels on mortality of septic patients: A systematic review and meta-analysis of cohort studies 被引量:8
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作者 Shao-hua Liu Huo-yan Liang +3 位作者 Hong-yi Li Xian-fei Ding Tong-wen Sun Jing Wang 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2020年第2期109-116,共8页
BACKGROUND:An increase in high-density lipoprotein(HDL)is well associated with a decreased cardiovascular risk,especially atherosclerosis.Recent studies suggest that lower levels of HDL may also be associated with an ... BACKGROUND:An increase in high-density lipoprotein(HDL)is well associated with a decreased cardiovascular risk,especially atherosclerosis.Recent studies suggest that lower levels of HDL may also be associated with an increased risk of sepsis and an increased rate of mortality in septic patients.However,this conclusion remains controversial.METHODS:MEDLINE,EMBASE,and CENTRAL databases were searched from inception to September 30,2019.All studies were conducted to evaluate the correlation of lipoprotein levels and the risk and outcomes of sepsis in adult patients.The primary outcomes were the risk and mortality of sepsis.RESULTS:Seven studies comprising 791 patients were included.Lower levels of HDL had no marked relevance with the risk of sepsis(odds radio[OR]for each 1 mg/dL increase,0.94;95%CI 0.86–1.02;P=0.078),whereas lower HDL levels were related to an increased mortality rate in septic patients(OR for below about median HDL levels,2.00;95%CI 1.23–3.24;P=0.005).CONCLUSION:This meta-analysis did not reveal a signifi cant association between lower HDL levels and an increase in the risk of sepsis,whereas it showed that lower HDL levels are associated with a higher mortality rate in septic adult patients.These findings suggest that HDL may be considered as a promising factor for the prevention and treatment of sepsis in the future. 展开更多
关键词 high-density lipoprotein SEPSIS MORTALITY META-ANALYSIS
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High-density lipoproteins:an emerging target in the prevention of cardiovascular disease 被引量:6
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作者 Belinda A Cutri Neil J Hime Stephen J Nicholls 《Cell Research》 SCIE CAS CSCD 2006年第10期799-808,共10页
High-density lipoproteins (HDLs) have been well established to protect against the development of atherosclerotic cardiovascular disease. It has become apparent that in addition to the promotion of reverse cholester... High-density lipoproteins (HDLs) have been well established to protect against the development of atherosclerotic cardiovascular disease. It has become apparent that in addition to the promotion of reverse cholesterol transport, HDLs possess a number of additional functional properties that may contribute to their beneficial influence on the arterial wall. A number of exciting therapeutic strategies have been developed that target HDL and its ability to protect against the development of atherosclerotic plaque. This paper will review how the promotion of the functional properties of HDL inhibits the formation of atherosclerotic plaque and stabilises lesions in patients with established disease. 展开更多
关键词 high-density lipoproteins cardiovascular disease atherosclerotic plaque stabilises lesions
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High-density lipoprotein as a potential carrier for delivery of a lipophilic antitumoral drug into hepatoma cells 被引量:12
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作者 BinLou Xue-LingLiao Man-PingWu Pei-FangCheng Chun-YanYin ZhengFei 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第7期954-959,共6页
AIM: To investigate the possibility of recombinant highdensity lipoprotein (rHDL) being a carrier for delivering antitumoral drug to hepatoma cells. METHODS: Recombinant complex of HDL and aclacinomycin (rHDL-ACM) was... AIM: To investigate the possibility of recombinant highdensity lipoprotein (rHDL) being a carrier for delivering antitumoral drug to hepatoma cells. METHODS: Recombinant complex of HDL and aclacinomycin (rHDL-ACM) was prepared by cosonication of apoproteins from HDL (Apo HDL) and ACM as well as phosphatidylcholine. Characteristics of the rHDL-ACM were elucidated by electrophoretic mobility, including the size of particles, morphology and entrapment efficiency. Binding activity of rHDL-ACM to human hepatoma cells was determined by competition assay in the presence of excess native HDL. The cytotoxicity of rHDL-ACM was assessed by MTT method. RESULTS: The density range of rHDL-ACM was 1.063-1.210 g/mL, and the same as that of native HDL. The purity of all rHDL-ACM preparations was more than 92%. Encapsulated efficiencies of rHDL-ACM were more than 90%. rHDL-ACM particles were typical sphere model of lipoproteins and heterogeneous in particle size. The average diameter was 31.26±5.62 nm by measure of 110 rHDL-ACM particles in the range of diameter of lipoproteins. rHDL-ACM could bind on SMMC-7721 cells, and such binding could be competed against in the presence of excess native HDL. rHDL-ACM had same binding capacity as native HDL. The cellular uptake of rHDL-ACM by SMMC-7721 hepatoma cells was significantly higher than that of free ACM at the concentration range of 0.5-10 μg/mL (P<0.01). Cytotoxicity of rHDL-ACM to SMMC-7721 cells was significantly higher than that of free ACM at concentration range of less than 5 ug/mL (P<0.01) and IC50 of rHDL-ACM was lower than IC50 of free ACM (1.68 nmol/L vs3 nmol/L). Compared to L02 hepatocytes, a normal liver cell line, the cellular uptake of rHDL-ACM by SMMC-7721 cells was significantly higher (P<0.01) and in a dose-dependent manner at the concentration range of 0.5-10 μg/mL.Cytotoxicity of the rHDL-ACM to SMMC- 7721 cells was significantly higher than that to L02 cells at concentration range of 1-7.5μg/mL (P<0.01). IC50 for SMMC-7721 cells (1.68 nmol/L) was lower than that for L02 cells (5.68 nmol/L), showing a preferential cytotoxicity of rHDL-ACM for SMMC-7721 cells. CONCLUSION: rHDL-ACM complex keeps the basic physical and biological binding properties of native HDL and shows a preferential cytotoxicity for SMMC-7721 hepatoma to normal L02 hepatocytes, HDL is a potential carrier for delivering lipophilic antitumoral drug to hepatoma cells. 展开更多
关键词 high-density lipoprotein CARRIER Antitumoral drug: SMMC-7721 hepatoma cell
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