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Ferrimagnetic Properties of Bond Dilution Mixed Blume-Capel Model with Random Single-Ion Anisotropy
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作者 LIU Lei YAN Shi-Lei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期743-748,共6页
We study the ferrimagnetic properties of spin 1/2 and spin-1 systems by means of the effective field theory. The system is considered in the framework of bond dilution mixed Blume-Capel mode/ (BCM) with random singl... We study the ferrimagnetic properties of spin 1/2 and spin-1 systems by means of the effective field theory. The system is considered in the framework of bond dilution mixed Blume-Capel mode/ (BCM) with random single-ion anisotropy. The investigation of phase diagrams and magnetization curves indicates the existence of induced magnetic ordering and single or multi-compensation points. Special emphasis is placed on the influence of bond dilution and random single-ion anisotropy on normal or induced magnetic ordering states and single or multi-compensation points. Normal magnetic ordering states take on new phase diagrams with increasing randomness (bond and anisotropy), while anisotropy induced magnetic ordering states are always occurrence no matter whether concentration of anisotropy is large or small. Existence and disappearance of compensation points rely strongly on bond dilution and random singleion anisotropy. Some results have not been revealed in previous papers and predicted by Néel theory of ferrimagnetism. 展开更多
关键词 ferrimagnetic property mixed Blume-Capel model induced magnetic ordering compensation point bond dilution and random single-ion anisotropy
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基于JK落重和Bond球磨功指数试验的铁矿石碎磨特性及流程模拟计算
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作者 杨晓峰 孙昊 +2 位作者 傅国辉 余建文 谷安成 《有色金属(选矿部分)》 CAS 2024年第5期172-179,共8页
弓长岭选厂目前采用传统的“三段一闭路破碎”、“阶段磨矿”的碎磨工艺流程,存在生产工艺流程长且磨矿能耗偏高等问题。因此拟在粗碎后增加(半)自磨作业,降低进入球磨物料的粒度,以期降低磨矿作业能耗,优化碎磨作业工艺流程,提高选厂... 弓长岭选厂目前采用传统的“三段一闭路破碎”、“阶段磨矿”的碎磨工艺流程,存在生产工艺流程长且磨矿能耗偏高等问题。因此拟在粗碎后增加(半)自磨作业,降低进入球磨物料的粒度,以期降低磨矿作业能耗,优化碎磨作业工艺流程,提高选厂的作业生产能力,降低磨矿作业生产成本。试验原料铁矿石品位为28.27%,其中铁主要以磁铁矿的形式存在,脉石主要为SiO2,含量为48.61%。以鞍钢弓长岭选厂作业流程中粗碎产品进行JK落重试验,细碎产品进行Bond球磨功指数试验,对矿石的碎磨特性参数进行深入研究。研究结果表明,矿石的冲击破碎模型t10=70.099×(1-exp-0.647×Ecs),其中A为冲击粉碎参数,其值为70.099,b为0.647,A×b为45.354,矿石的抗冲击破碎能力属于中等级别,且随着颗粒粒度的减小而增大;矿石磨蚀系数ta为0.361,抗磨蚀能力为中等级别;矿石的相对密度为3.26。Bond球磨功指数试验获得的功指数Wib=11.7665kWh/t,属于中硬矿石,可以采用(半)自磨工艺。半自磨机设计给矿粒度为F80=160mm,最终产品粒度P80=86μm,JKsimMet软件模拟结果表明,需要2台Φ8.8m×5.1m半自磨机(装机功率7000kW)可满足生产要求。该试验结果对后续选厂工艺流程的优化具有重要意义。 展开更多
关键词 bond功指数 JK落重试验 碎磨参数 冲击 磨蚀
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Accelerating Oxygen Electrocatalysis Kinetics on Metal-Organic Frameworks via Bond Length Optimization 被引量:2
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作者 Fan He Yingnan Liu +10 位作者 Xiaoxuan Yang Yaqi Chen Cheng‑Chieh Yang Chung‑Li Dong Qinggang He Bin Yang Zhongjian Li Yongbo Kuang Lecheng Lei Liming Dai Yang Hou 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期279-290,共12页
Metal-organic frameworks(MOFs)have been developed as an ideal platform for exploration of the relationship between intrinsic structure and catalytic activity,but the limited catalytic activity and stability has hamper... Metal-organic frameworks(MOFs)have been developed as an ideal platform for exploration of the relationship between intrinsic structure and catalytic activity,but the limited catalytic activity and stability has hampered their practical use in water splitting.Herein,we develop a bond length adjustment strategy for optimizing naphthalene-based MOFs that synthesized by acid etching Co-naphthalenedicarboxylic acid-based MOFs(donated as AE-CoNDA)to serve as efficient catalyst for water splitting.AE-CoNDA exhibits a low overpotential of 260 mV to reach 10 mA cm^(−2)and a small Tafel slope of 62 mV dec^(−1)with excellent stability over 100 h.After integrated AE-CoNDA onto BiVO_(4),photocurrent density of 4.3 mA cm^(−2)is achieved at 1.23 V.Experimental investigations demonstrate that the stretched Co-O bond length was found to optimize the orbitals hybridization of Co 3d and O 2p,which accounts for the fast kinetics and high activity.Theoretical calculations reveal that the stretched Co-O bond length strengthens the adsorption of oxygen-contained intermediates at the Co active sites for highly efficient water splitting. 展开更多
关键词 Metal-organic frameworks bond length adjustment Spin state transition Orbitals hybridization Water splitting
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Theoretical and experimental study of a bi-stable piezoelectric energy harvester under hybrid galloping and band-limited random excitations 被引量:1
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作者 Haitao LI Tianyu ZHENG +4 位作者 Weiyang QIN Ruilan TIAN Hu DING J.C.JI Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第3期461-478,共18页
In the practical environment,it is very common for the simultaneous occurrence of base excitation and crosswind.Scavenging the combined energy of vibration and wind with a single energy harvesting structure is fascina... In the practical environment,it is very common for the simultaneous occurrence of base excitation and crosswind.Scavenging the combined energy of vibration and wind with a single energy harvesting structure is fascinating.For this purpose,the effects of the wind speed and random excitation level are investigated with the stochastic averaging method(SAM)based on the energy envelope.The results of the analytical prediction are verified with the Monte-Carlo method(MCM).The numerical simulation shows that the introduction of wind can reduce the critical excitation level for triggering an inter-well jump and make a bi-stable energy harvester(BEH)realize the performance enhancement for a weak base excitation.However,as the strength of the wind increases to a particular level,the influence of the random base excitation on the dynamic responses is weakened,and the system exhibits a periodic galloping response.A comparison between a BEH and a linear energy harvester(LEH)indicates that the BEH demonstrates inferior performance for high-speed wind.Relevant experiments are conducted to investigate the validity of the theoretical prediction and numerical simulation.The experimental findings also show that strong random excitation is favorable for the BEH in the range of low wind speeds.However,as the speed of the incoming wind is up to a particular level,the disadvantage of the BEH becomes clear and evident. 展开更多
关键词 bi-stability inter-well response GALLOPING band-limited random
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Immune cell signatures and causal association with irritable bowel syndrome:A mendelian randomization study 被引量:1
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作者 Wei-Hao Chai Yan Ma +3 位作者 Jia-Jia Li Fei Guo Yi-Zhan Wu Jiang-Wei Liu 《World Journal of Clinical Cases》 SCIE 2024年第17期3094-3104,共11页
BACKGROUND The mucosal barrier's immune-brain interactions,pivotal for neural development and function,are increasingly recognized for their potential causal and therapeutic relevance to irritable bowel syndrome(I... BACKGROUND The mucosal barrier's immune-brain interactions,pivotal for neural development and function,are increasingly recognized for their potential causal and therapeutic relevance to irritable bowel syndrome(IBS).Prior studies linking immune inflammation with IBS have been inconsistent.To further elucidate this relationship,we conducted a Mendelian randomization(MR)analysis of 731 immune cell markers to dissect the influence of various immune phenotypes on IBS.Our goal was to deepen our understanding of the disrupted brain-gut axis in IBS and to identify novel therapeutic targets.AIM To leverage publicly available data to perform MR analysis on 731 immune cell markers and explore their impact on IBS.We aimed to uncover immunophenotypic associations with IBS that could inform future drug development and therapeutic strategies.METHODS We performed a comprehensive two-sample MR analysis to evaluate the causal relationship between immune cell markers and IBS.By utilizing genetic data from public databases,we examined the causal associations between 731 immune cell markers,encompassing median fluorescence intensity,relative cell abundance,absolute cell count,and morphological parameters,with IBS susceptibility.Sensitivity analyses were conducted to validate our findings and address potential heterogeneity and pleiotropy.RESULTS Bidirectional false discovery rate correction indicated no significant influence of IBS on immunophenotypes.However,our analysis revealed a causal impact of IBS on 30 out of 731 immune phenotypes(P<0.05).Nine immune phenotypes demonstrated a protective effect against IBS[inverse variance weighting(IVW)<0.05,odd ratio(OR)<1],while 21 others were associated with an increased risk of IBS onset(IVW≥0.05,OR≥1).CONCLUSION Our findings underscore a substantial genetic correlation between immune cell phenotypes and IBS,providing valuable insights into the pathophysiology of the condition.These results pave the way for the development of more precise biomarkers and targeted therapies for IBS.Furthermore,this research enriches our comprehension of immune cell roles in IBS pathogenesis,offering a foundation for more effective,personalized treatment approaches.These advancements hold promise for improving IBS patient quality of life and reducing the disease burden on individuals and their families. 展开更多
关键词 Irritable bowel syndrome Immunophenotypes CAUSALITY Brain-gut axis Mendelian randomization Sensitivity analysis
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An Optimized System of Random Forest Model by Global Harmony Search with Generalized Opposition-Based Learning for Forecasting TBM Advance Rate 被引量:1
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作者 Yingui Qiu Shuai Huang +3 位作者 Danial Jahed Armaghani Biswajeet Pradhan Annan Zhou Jian Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2873-2897,共25页
As massive underground projects have become popular in dense urban cities,a problem has arisen:which model predicts the best for Tunnel Boring Machine(TBM)performance in these tunneling projects?However,performance le... As massive underground projects have become popular in dense urban cities,a problem has arisen:which model predicts the best for Tunnel Boring Machine(TBM)performance in these tunneling projects?However,performance level of TBMs in complex geological conditions is still a great challenge for practitioners and researchers.On the other hand,a reliable and accurate prediction of TBM performance is essential to planning an applicable tunnel construction schedule.The performance of TBM is very difficult to estimate due to various geotechnical and geological factors and machine specifications.The previously-proposed intelligent techniques in this field are mostly based on a single or base model with a low level of accuracy.Hence,this study aims to introduce a hybrid randomforest(RF)technique optimized by global harmony search with generalized oppositionbased learning(GOGHS)for forecasting TBM advance rate(AR).Optimizing the RF hyper-parameters in terms of,e.g.,tree number and maximum tree depth is the main objective of using the GOGHS-RF model.In the modelling of this study,a comprehensive databasewith themost influential parameters onTBMtogetherwithTBM AR were used as input and output variables,respectively.To examine the capability and power of the GOGHSRF model,three more hybrid models of particle swarm optimization-RF,genetic algorithm-RF and artificial bee colony-RF were also constructed to forecast TBM AR.Evaluation of the developed models was performed by calculating several performance indices,including determination coefficient(R2),root-mean-square-error(RMSE),and mean-absolute-percentage-error(MAPE).The results showed that theGOGHS-RF is a more accurate technique for estimatingTBMAR compared to the other applied models.The newly-developedGOGHS-RFmodel enjoyed R2=0.9937 and 0.9844,respectively,for train and test stages,which are higher than a pre-developed RF.Also,the importance of the input parameters was interpreted through the SHapley Additive exPlanations(SHAP)method,and it was found that thrust force per cutter is the most important variable on TBMAR.The GOGHS-RF model can be used in mechanized tunnel projects for predicting and checking performance. 展开更多
关键词 Tunnel boring machine random forest GOGHS optimization PSO optimization GA optimization ABC optimization SHAP
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Causal associations between gastroesophageal reflux disease and essential hypertension: A bidirectional Mendelian randomization study 被引量:1
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作者 Ning Wei Ming-Hui Liu Yu-Hu Song 《World Journal of Clinical Cases》 SCIE 2024年第5期880-890,共11页
BACKGROUND Clinical studies have reported that patients with gastroesophageal reflux disease(GERD)have a higher prevalence of hypertension.AIM To performed a bidirectional Mendelian randomization(MR)analysis to invest... BACKGROUND Clinical studies have reported that patients with gastroesophageal reflux disease(GERD)have a higher prevalence of hypertension.AIM To performed a bidirectional Mendelian randomization(MR)analysis to investi-gate the causal link between GERD and essential hypertension.METHODS Eligible single nucleotide polymorphisms(SNPs)were selected,and weighted median,inverse variance weighted(IVW)as well as MR egger(MR-Egger)re-gression were used to examine the potential causal association between GERD and hypertension.The MR-Pleiotropy RESidual Sum and Outlier analysis was used to detect and attempt to reduce horizontal pleiotropy by removing outliers SNPs.The MR-Egger intercept test,Cochran’s Q test and“leave-one-out”sen-sitivity analysis were performed to evaluate the horizontal pleiotropy,heterogen-eities,and stability of single instrumental variable.RESULTS IVW analysis exhibited an increased risk of hypertension(OR=1.46,95%CI:1.33-1.59,P=2.14E-16)in GERD patients.And the same result was obtained in replication practice(OR=1.002,95%CI:1.0008-1.003,P=0.000498).Meanwhile,the IVW analysis showed an increased risk of systolic blood pressure(β=0.78,95%CI:0.11-1.44,P=0.021)and hypertensive heart disease(OR=1.68,95%CI:1.36-2.08,P=0.0000016)in GERD patients.Moreover,we found an decreased risk of Barrett's esophagus(OR=0.91,95%CI:0.83-0.99,P=0.043)in essential hypertension patients.CONCLUSION We found that GERD would increase the risk of essential hypertension,which provided a novel prevent and therapeutic perspectives of essential hypertension. 展开更多
关键词 Gastroesophageal reflux disease Essential hypertension Hypertensive heart disease Mendelian randomization study
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Covalency competition induced selective bond breakage and surface reconstruction in manganese cobaltite towards enhanced electrochemical charge storage 被引量:1
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作者 Peng Gao Pei Tang +7 位作者 Ying Mo Peitao Xiao Wang Zhou Shi Chen Hongliang Dong Ziwei Li Chaohe Xu Jilei Liu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期909-918,共10页
Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn ... Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn are prone to react with the hydroxyl ions in alkaline electrolyte upon electrochemical cycling and separates on the surface of spinel to reconstruct into d-MnO_(2) nanosheets irreversibly,thus results in a change of the reaction mechanism with Kþion intercalation.However,the low capacity has greatly limited its practical application.Herein,we found that the tetrahedrally-coordinated Co_(2) þions were leached when MnCo_(2)_(4) was equilibrated in 1 mol L^(-1) HCl solution,leading to the formation of layered CoOOH on MnCo_(2)_(4) surface which is originated from the covalency competition induced selective breakage of the CoT–O bond in CoT–O–CoO and subsequent rearrangement of free Co_(6) octahedra.The as-formed CoOOH is stable upon cycling in alkaline electrolyte,exhibits conversion reaction mechanism with facile proton diffusion and is free of massive structural evolution,thus enables utilization of the bulk electrode material and realizes enhanced specific capacity as well as facilitated charge transfer and ion diffusion.In general,our work not only offers a feasible approach to deliberate modification of MnCo_(2)_(4)'s surface structure,but also provides an in-depth understanding of its charge storage mechanism,which enables rational design of the spinel oxides with promising charge storage properties. 展开更多
关键词 Manganese cobaltite Tetrahedrally-coordinated Co^(2+)leaching Selective bond breakage Surface reconstruction Charge storage mechanisms
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Transient liquid phase bonding of DD5 superalloy using a designed interlayer: microstructure and mechanical properties 被引量:1
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作者 周昌杰 范骁乐 +3 位作者 朱立华 陈闯 贺建超 计红军 《China Welding》 CAS 2024年第2期1-10,共10页
Nickel based single crystal superalloy is currently widely used as the material for turbine blades in aerospace engines.However,metallurgical defects during the manufacturing process and damage during harsh environmen... Nickel based single crystal superalloy is currently widely used as the material for turbine blades in aerospace engines.However,metallurgical defects during the manufacturing process and damage during harsh environmental service are inevitable challenges for turbine blades.Therefore,bonding techniques play a very important role in the manufacturing and repair of turbine blades.The transient liquid phase(TLP)bonding of DD5 Ni-based single crystal superalloy was performed using the designed H1 interlayer.A new third-generation Ni-based superalloy T1 powder was mixed with H1 powder as another interlayer to improve the mechanical properties of the bonded joints.The res-ults show that,such a designed H1 interlayer is beneficial to the improvement of shear strength of DD5 alloy bonded joints by adjusting the bonding temperature and the prolongation of holding time.The maximum shear strength at room temperature of the joint with H1 interlayer reached 681 MPa when bonded at 1260℃for 3 h.The addition of T1 powder can effectively reduce holding time or relatively lower bond-ing temperature,while maintaining relatively high shear strength.When 1 wt.%T1 powder was mixed into H1 interlayer,the maximum room temperature shear strength of the joint bonded at 1260℃reached 641 MPa,which could be obtained for only 1 h.Considering the bonding temperature and the efficiency,the acceptable process parameter of H1+5 wt.%T1 interlayer was 1240℃/2 h,and the room tem-perature shear strength reached 613 MPa. 展开更多
关键词 Ni-based superalloy powder transient liquid phase bonded joint shear strength
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Genetically predicted fatty liver disease and risk of psychiatric disorders: A mendelian randomization study 被引量:1
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作者 Wei-Ming Xu Hai-Fu Zhang +2 位作者 Yong-Hang Feng Shuo-Jun Li Bi-Yun Xie 《World Journal of Clinical Cases》 SCIE 2024年第14期2359-2369,共11页
BACKGROUND Non-alcoholic fatty liver disease(NAFLD)and alcohol-related liver disease(Ar-LD)constitute the primary forms of chronic liver disease,and their incidence is progressively increasing with changes in lifestyl... BACKGROUND Non-alcoholic fatty liver disease(NAFLD)and alcohol-related liver disease(Ar-LD)constitute the primary forms of chronic liver disease,and their incidence is progressively increasing with changes in lifestyle habits.Earlier studies have do-cumented a correlation between the occurrence and development of prevalent mental disorders and fatty liver.AIM To investigate the correlation between fatty liver and mental disorders,thus ne-cessitating the implementation of a mendelian randomization(MR)study to elu-cidate this association.METHODS Data on NAFLD and ArLD were retrieved from the genome-wide association studies catalog,while information on mental disorders,including Alzheimer's disease,schizophrenia,anxiety disorder,attention deficit hyperactivity disorder(ADHD),bipolar disorder,major depressive disorder,multiple personality dis-order,obsessive-compulsive disorder(OCD),post-traumatic stress disorder(PTSD),and schizophrenia was acquired from the psychiatric genomics consor-tium.A two-sample MR method was applied to investigate mediators in signifi-cant associations.RESULTS After excluding weak instrumental variables,a causal relationship was identified between fatty liver disease and the occurrence and development of some psychia-tric disorders.Specifically,the findings indicated that ArLD was associated with a significantly elevated risk of developing ADHD(OR:5.81,95%CI:5.59-6.03,P<0.01),bipolar disorder(OR:5.73,95%CI:5.42-6.05,P=0.03),OCD(OR:6.42,95%CI:5.60-7.36,P<0.01),and PTSD(OR:5.66,95%CI:5.33-6.01,P<0.01).Meanwhile,NAFLD significantly increased the risk of developing bipolar disorder(OR:55.08,95%CI:3.59-845.51,P<0.01),OCD(OR:61.50,95%CI:6.69-565.45,P<0.01),and PTSD(OR:52.09,95%CI:4.24-639.32,P<0.01).CONCLUSION Associations were found between genetic predisposition to fatty liver disease and an increased risk of a broad range of psychiatric disorders,namely bipolar disorder,OCD,and PTSD,highlighting the significance of preven-tive measures against psychiatric disorders in patients with fatty liver disease. 展开更多
关键词 Non-alcoholic fatty liver disease Alcohol-related liver disease Psychiatric disorders Mendelian randomization Single nucleotide polymorphisms
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一种基于KMeans与Random Forest的异常温升捕捉方法
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作者 汪海良 《现代建筑电气》 2024年第6期21-26,49,共7页
针对线路老化、线路过载的火灾频发问题,分析了线路老化、线路过载与异常温升之间的关联性,以电流值、线缆温度作为输入,利用KMeans聚类算法划分可能存在异常温升的区间,通过Random Forest算法识别线路过载问题,可以提前通知用户整改线... 针对线路老化、线路过载的火灾频发问题,分析了线路老化、线路过载与异常温升之间的关联性,以电流值、线缆温度作为输入,利用KMeans聚类算法划分可能存在异常温升的区间,通过Random Forest算法识别线路过载问题,可以提前通知用户整改线路,预防火灾的发生。 展开更多
关键词 线路过载 异常温升 random Forest KMeans
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Hybrid bonding of GaAs and Si wafers at low temperature by Ar plasma activation
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作者 Rui Huang Zhiyong Wang +3 位作者 Kai Wu Hao Xu Qing Wang Yecai Guo 《Journal of Semiconductors》 EI CAS CSCD 2024年第4期69-75,共7页
High-quality bonding of 4-inch GaAs and Si is achieved using plasma-activated bonding technology.The influence of Ar plasma activation on surface morphology is discussed.When the annealing temperature is 300℃,the bon... High-quality bonding of 4-inch GaAs and Si is achieved using plasma-activated bonding technology.The influence of Ar plasma activation on surface morphology is discussed.When the annealing temperature is 300℃,the bonding strength reaches a maximum of 6.2 MPa.In addition,a thermal stress model for GaAs/Si wafers is established based on finite element analysis to obtain the distribution of equivalent stress and deformation variables at different temperatures.The shape varia-tion of the wafer is directly proportional to the annealing temperature.At an annealing temperature of 400℃,the maximum protrusion of 4 inches GaAs/Si wafers is 3.6 mm.The interface of GaAs/Si wafers is observed to be dense and defect-free using a transmission electron microscope.The characterization of interface elements by X-ray energy dispersion spectroscopy indi-cates that the elements at the interface undergo mutual diffusion,which is beneficial for improving the bonding strength of the interface.There is an amorphous transition layer with a thickness of about 5 nm at the bonding interface.The preparation of Si-based GaAs heterojunctions can enrich the types of materials required for the development of integrated circuits,improve the performance of materials and devices,and promote the development of microelectronics technology. 展开更多
关键词 plasma-activated bonding bonding strength thermal stress model mutual diffusion
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Exploring the Impact of Alcohol Consumption and Smoking on Primary Open Angle Glaucoma: A Mendelian Randomization Study
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作者 Meng Xu Longlong Chen +1 位作者 Dongkan Li Bin Lin 《American Journal of Molecular Biology》 CAS 2024年第3期152-165,共14页
Objective: Utilizing Mendelian Randomization, this study employs Single Nucleotide Polymorphisms (SNPs) as instrumental variables to explore the causal relationships between bibulosity, smoking, and Primary Open Angle... Objective: Utilizing Mendelian Randomization, this study employs Single Nucleotide Polymorphisms (SNPs) as instrumental variables to explore the causal relationships between bibulosity, smoking, and Primary Open Angle Glaucoma (POAG). Methods: GWAS data for bibulosity, smoking, and POAG were obtained from the Social Science Genetic Association Consortium website and the IEU OpenGWAS Project website, respectively. Using a P-value threshold of −8, a linkage disequilibrium coefficient (r2) of 0.001, and a linkage disequilibrium region width of 10,000 kb, the data were aggregated, resulting in 6 SNPs for bibulosity and 253 SNPs for smoking. Three regression models, MR-Egger, Weighted Median Estimator (WME), and Random-Effects Inverse-Variance Weighted (IVW) were applied to analyze the causal impact of bibulosity and smoking on POAG. Results: The GWAS data for alcohol consumption and smoking were derived from European populations, while the GWAS data for Primary Open-Angle Glaucoma (POAG) were sourced from East Asian populations, with no gender restrictions. Analysis using three different regression models revealed that neither excessive alcohol consumption nor smoking significantly increased the risk of developing POAG. Specifically, the odds ratios with 95% confidence intervals for the alcohol consumption group were 0.854 (0.597 - 1.221) in MR-Egger regression, 0.922 (0.691 - 1.231) in WME regression, and 0.944 (0.711 - 1.252) in IVW regression. For the smoking group, the odds ratios were 1.146 (0.546 - 2.406) in MR-Egger regression, 0.850 (0.653 - 1.111) in WME regression, and 0.939 (0.780 - 1.131) in IVW regression. Given the significant heterogeneity in the SNPs associated with smoking, the focus was primarily on the results from the IVW regression model. Conclusion: Alcohol consumption and smoking are not significant risk factors for the development of POAG. 展开更多
关键词 Alcohol Abuse SMOKING GLAUCOMA Causal Relationship Mendelian randomization
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Python语言random库经典案例教学 被引量:1
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作者 崔赛英 《电脑编程技巧与维护》 2024年第5期19-21,44,共4页
Python是一种计算生态语言,也是开源的语言,具有丰富和强大的类库,语法简洁、清晰明了。随着物联网、大数据、人工智能等技术的兴起,Python位于PYPL全球编程语言排行榜的榜首,成为受人们欢迎的编程语言。主要阐述利用Python的random库... Python是一种计算生态语言,也是开源的语言,具有丰富和强大的类库,语法简洁、清晰明了。随着物联网、大数据、人工智能等技术的兴起,Python位于PYPL全球编程语言排行榜的榜首,成为受人们欢迎的编程语言。主要阐述利用Python的random库解决一些实际问题,既提高学习者的兴趣和积极性,又能提高学习者利用所学知识分析和处理实际问题的能力。 展开更多
关键词 PYTHON语言 random 案例教学
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Understanding the educational inequalities in suicide attempts and their mediators:a Mendelian randomisation study
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作者 Jiahao Zhu Houpu Liu +5 位作者 Rui Gao Lilu Ding Jing Wang Ye Yang Dan Zhou Yingjun Li 《General Psychiatry》 CSCD 2024年第1期133-142,共10页
Background Educational inequalities in suicide have become increasingly prominent over the past decade.Elucidating modifiable risk factors that serve as intermediaries in the impact of low educational attainment on su... Background Educational inequalities in suicide have become increasingly prominent over the past decade.Elucidating modifiable risk factors that serve as intermediaries in the impact of low educational attainment on suicide has the potential to reduce health disparities.Aims To examine the risk factors that mediate the relationship between educational attainment and suicide attempts and quantify their contributions to the mediation effect.Methods We conducted a two-sample Mendelian randomisation(MR)analysis to estimate the causal effect of educational attainment on suicide attempts,utilising genome-wide association study summary statistics from the Integrative Psychiatric Research(iPSYCH;6024 cases and 44240 controls)and FinnGen(8978 cases and 368299 controls).We systematically evaluated 42 putative mediators within the causal pathway connecting reduced educational attainment to suicide attempts and employed two-step and multivariable MR to quantify the proportion of the mediated effect.Results In the combined analysis of iPSYCH and FinnGen,each standard deviation(SD)decrease in genetically predicted educational attainment(equating to 3.4 years of education)was associated with a 105%higher risk of suicide attempts(odds ratio(OR):2.05;95%confidence interval(Cl):1.81 to 2.31).0f the 42 risk factors analysed,the two-step MR identified five factors that mediated the association between educational attainment and suicide attempts.The respective proportions of mediation were 47%(95%Cl:29%to 66%)for smoking behaviour,36%(95%Cl:0%to 84%)for chronic pain,49%(95%Cl:36%to 61%)for depression,35%(95%Cl:12%to 59%)for anxiety and 26%(95%Cl:18%to 34%)for insomnia.Multivariable MR implicated these five mediators collectively,accounting for 68%(95%Cl:40%to 96%)of the total effect.Conclusions This study identified smoking,chronic pain and mental disorders as primary intervention targets for attenuating suicide risk attributable to lower educational levels in the European population. 展开更多
关键词 effect. random INEQUALITIES
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Different effects of 24 dietary intakes on gastroesophageal reflux disease: A mendelian randomization
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作者 Yu-Xin Liu Wen-Tao Yang Yang Li 《World Journal of Clinical Cases》 SCIE 2024年第14期2370-2381,共12页
BACKGROUND In observational studies,dietary intakes are associated with gastroesophageal re-flux disease(GERD).AIM To conduct a two-sample mendelian randomization(MR)analysis to determine whether those associations ar... BACKGROUND In observational studies,dietary intakes are associated with gastroesophageal re-flux disease(GERD).AIM To conduct a two-sample mendelian randomization(MR)analysis to determine whether those associations are causal.METHODS To explore the relationship between dietary intake and the risk of GERD,we extracted appropriate single nucleotide polymorphisms from genome-wide asso-ciation study data on 24 dietary intakes.Three methods were adopted for data analysis:Inverse variance weighting,weighted median methods,and MR-Egger's method.The odds ratio(OR)and 95%confidence interval(CI)were used to eva-luate the causal association between dietary intake and GERD.RESULTS Our univariate Mendelian randomization(UVMR)results showed significant evidence that pork intake(OR,2.83;95%CI:1.76-4.55;P=1.84×10–5),beer intake(OR,2.70,95%CI:2.00-3.64;P=6.54×10–11),non-oily fish intake(OR,2.41;95%CI:1.49-3.91;P=3.59×10–4)have a protective effect on GERD.In addition,dried fruit intake(OR,0.37;95%CI:0.27-0.50;6.27×10–11),red wine intake(OR,0.34;95%CI:0.25-0.47;P=1.90×10-11),cheese intake(OR,0.46;95%CI:0.39-0.55;P=3.73×10-19),bread intake(OR,0.72;95%CI:0.56-0.92;P=0.0009)and cereal intake(OR,0.45;95%CI:0.36-0.57;P=2.07×10-11)were negatively associated with the risk of GERD.There was a suggestive asso-ciation for genetically predicted coffee intake(OR per one SD increase,1.22,95%CI:1.03-1.44;P=0.019).Multi-variate Mendelian randomization further confirmed that dried fruit intake,red wine intake,cheese intake,and cereal intake directly affected GERD.In contrast,the impact of pork intake,beer intake,non-oily fish intake,and bread intake on GERD was partly driven by the common risk factors for GERD.However,after adjusting for all four elements,there was no longer a suggestive association between coffee intake and GERD.CONCLUSION This study provides MR evidence to support the causal relationship between a broad range of dietary intake and GERD,providing new insights for the treatment and prevention of GERD. 展开更多
关键词 DIETARY Gastroesophageal reflux disease Mendelian randomization Disease management randomized controlled trial
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Dissecting the association between gut microbiota,body mass index and specific depressive symptoms:a mediation Mendelian randomisation study
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作者 Tong Yu Chengfeng Chen +7 位作者 Yuqing Yang Mingqia Wang Yantianyu Yang Wanting Feng Shiqi Yuan Xiancang Ma Jie Li Bin Zhang 《General Psychiatry》 CSCD 2024年第4期492-501,共10页
Background Observational studies highlight the association between gut microbiota(GM)composition and depression;however,evidence for the causal relationship between GM and specific depressive symptoms remains lacking.... Background Observational studies highlight the association between gut microbiota(GM)composition and depression;however,evidence for the causal relationship between GM and specific depressive symptoms remains lacking.Aims We aimed to evaluate the causal relationship between GM and specific depressive symptoms as well as the mediating role of body mass index(BMI).Methods We performed a two-sample Mendelian randomisation(MR)analysis using genetic variants associated with GM and specific depressive symptoms from genome-wide association studies.The mediating role of BMI was subsequently explored using mediation analysis via two-step MR.Results MR evidence suggested the Bifidobacterium genus(β=0.03;95%CI-0.05 to-0.02;p<0.001 andβ=0.03;95%CI-0.05 to-0.02;p<0.001)and Actinobacteria phylum(β=-0.04;95%CI-0.06 to-0.02;p<0.001 andβ=-0.03;95%CI-0.05 to-0.03;p=0.001)had protective effects on both anhedonia and depressed mood.The Actinobacteria phylum also had protective effects on appetite changes(β=-0.04;95%CI-0.06 to-0.01;p=0.005),while the FamilyⅪhad an antiprotective effect(β=0.03;95%CI 0.01 to 0.04;p<0.001).The Bifidobacteriaceae family(β=-0.01;95%CI-0.02 to-0.01;p=0.001)and Actinobacteria phylum(β=-0.02;95%CI-0.03 to-0.01;p=0.001)showed protective effects against suicidality.The two-step MR analysis revealed that BMl also acted as a mediating moderator between the Actinobacteria phylum and appetite changes(mediated proportion,34.42%)and that BMI partially mediated the effect of the Bifidobacterium genus(14.14%and 8.05%)and Actinobacteria phylum(13.10%and 8.31%)on both anhedonia and depressed mood.Conclusions These findings suggest a potential therapeutic effect of Actinobacteria and Bifidobacterium on both depression and obesity.Further studies are required to translate these findings into clinical practice. 展开更多
关键词 protective SYMPTOMS random
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Strong invariance principle for a counterbalanced random walk
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作者 TAN Hui-qun HU Zhi-shui DONG Liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期370-380,共11页
We study a counterbalanced random walkS_(n)=X_(1)+…+X_(n),which is a discrete time non-Markovian process andX_(n) are given recursively as follows.For n≥2,X_(n) is a new independent sample from some fixed law̸=0 wit... We study a counterbalanced random walkS_(n)=X_(1)+…+X_(n),which is a discrete time non-Markovian process andX_(n) are given recursively as follows.For n≥2,X_(n) is a new independent sample from some fixed law̸=0 with a fixed probability p,andX_(n)=−X_(v(n))with probability 1−p,where v(n)is a uniform random variable on{1;…;n−1}.We apply martingale method to obtain a strong invariance principle forS_(n). 展开更多
关键词 random walk MARTINGALE invariance principle
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Socioeconomic traits and the risk of Barrett’s esophagus and gastroesophageal reflux disease: A Mendelian randomization study
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作者 Yu-Xin Liu Cheng-Li Bin +2 位作者 Lu Zhang Wen-Tao Yang Bai-Ping An 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2631-2645,共15页
BACKGROUND Previous observational studies have shown that the prevalence of gastroesophageal reflux disease(GERD)and Barrett’s esophagus(BE)is associated with socioeconomic status.However,due to the methodological li... BACKGROUND Previous observational studies have shown that the prevalence of gastroesophageal reflux disease(GERD)and Barrett’s esophagus(BE)is associated with socioeconomic status.However,due to the methodological limitations of traditional observational studies,it is challenging to definitively establish causality.AIM To explore the causal relationship between the prevalence of these conditions and socioeconomic status using Mendelian randomization(MR).METHODS We initially screened single nucleotide polymorphisms(SNPs)to serve as proxies for eight socioeconomic status phenotypes for univariate MR analysis.The inverse variance weighted(IVW)method was used as the primary analytical method to estimate the causal relationship between the eight socioeconomic status phenotypes and the risk of GERD and BE.We then collected combinations of SNPs as composite proxies for the eight socioeconomic phenotypes to perform multivariate MR(MVMR)analyses based on the IVW MVMR model.Furthermore,a two-step MR mediation analysis was used to examine the potential mediation of the associations by body mass index,major depressive disorder(MDD),smoking,alcohol consumption,and sleep duration.RESULTS The study identified three socioeconomic statuses that had a significant impact on GERD.These included household income[odds ratio(OR):0.46;95% confidence interval(95%CI):0.31-0.70],education attainment(OR:0.23;95%CI:0.18-0.29),and the Townsend Deprivation Index at recruitment(OR:1.57;95%CI:1.04-2.37).These factors were found to independently and predominantly influence the genetic causal effect of GERD.Furthermore,the mediating effect of educational attainment on GERD was found to be mediated by MDD(proportion mediated:10.83%).Similarly,the effect of educational attainment on BE was mediated by MDD(proportion mediated:10.58%)and the number of cigarettes smoked per day(proportion mediated:3.50%).Additionally,the mediating effect of household income on GERD was observed to be mediated by sleep duration(proportion mediated:9.75%)CONCLUSION This MR study shed light on the link between socioeconomic status and GERD or BE,providing insights for the prevention of esophageal cancer and precancerous lesions. 展开更多
关键词 Socioeconomic status Gastroesophageal reflux disease Barrett’s esophagus Two-step Mendelian randomization Multivariate Mendelian randomization
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OFDMA-Based Unsourced Random Access in LEO Satellite Internet of Things
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作者 Jiaqi Fang Gangle Sun +2 位作者 Wenjin Wang Li You Rui Ding 《China Communications》 SCIE CSCD 2024年第1期13-23,共11页
This paper investigates the low earth orbit(LEO)satellite-enabled coded compressed sensing(CCS)unsourced random access(URA)in orthogonal frequency division multiple access(OFDMA)framework,where a massive uniform plana... This paper investigates the low earth orbit(LEO)satellite-enabled coded compressed sensing(CCS)unsourced random access(URA)in orthogonal frequency division multiple access(OFDMA)framework,where a massive uniform planar array(UPA)is equipped on the satellite.In LEO satellite communications,unavoidable timing and frequency offsets cause phase shifts in the transmitted signals,substantially diminishing the decoding performance of current terrestrial CCS URA receiver.To cope with this issue,we expand the inner codebook with predefined timing and frequency offsets and formulate the inner decoding as a tractable compressed sensing(CS)problem.Additionally,we leverage the inherent sparsity of the UPA-equipped LEO satellite angular domain channels,thereby enabling the outer decoder to support more active devices.Furthermore,the outputs of the outer decoder are used to reduce the search space of the inner decoder,which cuts down the computational complexity and accelerates the convergence of the inner decoding.Simulation results verify the effectiveness of the proposed scheme. 展开更多
关键词 LEO OFDMA SATELLITE unsourced random access UPA
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