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L_(1)-Smooth SVM with Distributed Adaptive Proximal Stochastic Gradient Descent with Momentum for Fast Brain Tumor Detection

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Computers, Materials & Continua 2024年第5期79卷 1975-1994页

作者： Chuandong Qin yu cao Liqun Meng School of Mathematics and Information Science North Minzu UniversityYinchuan750021China Ningxia Key Laboratory of Intelligent Information and Big Data Processing Yinchuan750021China

Brain tumors come in various types,each with distinct characteristics and treatment approaches,making manual detection a time-consuming and potentially ambiguous *** tumor detection is a valuable tool for gaining a deeper understanding of tumors and improving treatment *** learning models have become key players in automating brain tumor *** descent methods are the mainstream algorithms for solving machine learning *** this paper,we propose a novel distributed proximal stochastic gradient descent approach to solve the L_(1)-Smooth Support Vector Machine(SVM)classifier for brain tumor ***,the smooth hinge loss is introduced to be used as the loss function of *** avoids the issue of nondifferentiability at the zero point encountered by the traditional hinge loss function during gradient descent ***,the L_(1) regularization method is employed to sparsify features and enhance the robustness of the ***,adaptive proximal stochastic gradient descent(PGD)with momentum,and distributed adaptive PGDwithmomentum(DPGD)are proposed and applied to the L_(1)-Smooth *** computing is crucial in large-scale data analysis,with its value manifested in extending algorithms to distributed clusters,thus enabling more efficient processing ofmassive amounts of *** DPGD algorithm leverages Spark,enabling full utilization of the computer’s multi-core *** to its sparsity induced by L_(1) regularization on parameters,it exhibits significantly accelerated convergence *** the perspective of loss reduction,DPGD converges faster than *** experimental results show that adaptive PGD withmomentumand its variants have achieved cutting-edge accuracy and efficiency in brain tumor ***-trained models,both the PGD andDPGD outperform other models,boasting an accuracy of 95.21%.

关键词： Support vector machine proximal stochastic gradient descent brain tumor detection distributed computing

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Applications of genetic code expansion technology in eukaryotes

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Protein & Cell 2024年第5期15卷 331-363页

作者： Qiao-ru Guo yu J.cao State Key Laboratory of Chemical Oncogenomic Guangdong Provincial Key Laboratory of Chemical GenomicsPeking University Shenzhen Graduate SchoolShenzhen 518055China Institute of Chemical Biology Shenzhen Bay LaboratoryShenzhen 518132China

Unnatural amino acids(UAAs)have gained significant attention in protein engineering and drug development owing to their ability to introduce new chemical functionalities to *** eukaryotes,genetic code expansion(GCE)enables the incorporation of UAAs and facilitates posttranscriptional modification(PTM),which is not feasible in prokaryotic *** is also a powerful tool for cell or animal imaging,the monitoring of protein interactions in target cells,drug development,and switch ***,there is keen interest in utilizing GCE in eukaryotic *** review provides an overview of the application of GCE in eukaryotic systems and discusses current challenges that need to be addressed.

关键词： genetic code expansion unnatural amino acid eukaryotes basic research therapeutic applications

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Aging Mongolian pine plantations face high risks of drought-induced growth decline:evidence from both individual tree and forest stand measurements

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Journal of Forestry Research 2024年第2期35卷 109-120页

作者： Mingyong Li Leilei Yang yu cao Dedong Wu Guangyou Hao CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China Key Laboratory of Terrestrial Ecosystem Carbon Neutrality Liaoning ProvinceShenyang 110016People’s Republic of China Daqinggou Ecological Research Station Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Research Institute of Sand Control and Utilization Liaoning ProvinceFuxin 123000People’s Republic of China

Discerning vulnerability differences among different aged trees to drought-driven growth decline or to mortality is critical to implement age-specific countermeasures for forest management in water-limited *** important species for afforestation in dry environments of northern China,Mongolian pine(Pinus sylvestris *** Litv.)has recently exhibited growth decline and dieback on many sites,particularly pronounced in old-growth ***,changes in response to drought stress by this species with age as well as the underlying mechanisms are poorly *** this study,tree-ring data and remotely sensed vegetation data were combined to investigate variations in growth at individual tree and stand scales for young(9-13 years)and aging(35-52 years)plantations of Mongolian pine in a water-limited area of northern China.A recent decline in tree-ring width in the older plantation also had lower values in satellited-derived normalized difference vegetation indices and normalized difference water indices relative to the younger *** addition,all measured growth-related metrics were strongly correlated with the self-calibrating Palmer drought severity index during the growing season in the older *** of growth to drought of the older plantation might be attributed to more severe hydraulic limitations,as reflected by their lower sapwood-and leaf-specific hydraulic *** study presents a comprehensive view on changes of growth with age by integrating multiple methods and provides an explanation from the perspective of plant hydraulics for growth decline with *** results indicate that old-growth Mongolian pine plantations in water-limited environments may face increased growth declines under the context of climate warming and drying.

关键词： Tree age Drought stress Mongolian pine plantation Tree rings Remote sensing Plant hydraulics

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Spatiotemporal variations of parameters of internal solitary waves in the northern South China Sea

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Journal of Oceanology and Limnology 2024年第2期42卷 421-438页

作者： yu’ang LIU Yifei JIANG Xiaojiang ZHANG Zhiyuan WANG yu cao Huizan WANG College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410000China

The dynamic parameters for internal solitary waves(ISWs)derived from the extended Korteweg-de Vries(eKdV)equation play an important role in the understanding and prediction of *** spatiotemporal variations of the dynamic parameters of the ISWs in the northern South China Sea(SCS)were studied based on the reanalysis of long-term temperature and salinity *** results for spectrum analysis show that there are definite geographical differences for the periodic variation of the parameters:in shallow water,all parameters vary with a wave period of one year,while in deep water wave components of the parameters at other frequencies *** wavelet analysis,the wavelet power spectral densities in deep water exhibited an inter-annual variation *** example,the wave component of the dispersion coefficient with a wave period of about half a year reached its power peak once every two *** on previous work,this inter-annual variation pattern was deduced to be caused by dynamic *** further work on the regulatory mechanisms,empirical orthogonal function(EOF)decomposition was *** was found that the modes of the dispersion coefficient have different geographical distributions,explaining the reason why the wave components in different frequencies appeared in different *** numerical simulation results confirm that the variations in the parameters of the ISWs derived from the eKdV equation could affect the waveforms significantly because of changes in the polarity of the ***,the periodic variations of the dynamic parameters are related to the geographical location because of dynamic processes operating.

关键词： internal solitary waves(ISWs) dynamic parameters eKdV equation spatiotemporal variation polarity empirical orthogonal function(EOF)decomposition

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Role of Stokes Drift in Ocean Dynamics Under Typhoon Conditions in the Bohai Sea

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Journal of Ocean University of China 2024年第1期23卷 33-45页

作者： LI Haoqian WAN Kai WANG Menghan DENG Zeng’an cao yu North China Sea Marine Forecasting Center Qingdao 266061China Shandong Provincial Key Laboratory of Marine Ecology and Environment&Disaster Prevention and Mitigation Qingdao 266061China North China Sea Offshore Engineering Survey Institute Qingdao 266061China School of Marine Science and Technology Tianjin UniversityTianjin 300072China South China Sea Marine Forecasting Center Guangzhou 510006China

The effect of Stokes drift production(SDP),which includes Coriolis-Stokes forcing,Langmuir circulation,and Craik-Lei-bovich vortexes,on the upper ocean during typhoon passage in the Bohai Sea(BS),China,is investigated by using a coupled wave-current *** role of SDP in turbulent mixing and the further dynamics during the entire typhoon period are comprehensively *** results show that SDP greatly increases turbulent mixing at all depths under typhoon conditions by up to seven times that under normal weather *** generally strengthens sea surface cooling by more than 0.4℃,with the maximum reduction in sea surface temperature(SST)at the during-typhoon stage exceeding 2℃,which is approximately seven times larger than that under normal weather *** SDP-induced decrease in current speed can exceed 0.2ms^(-1),and the change in current direction is generally opposite the wind *** results suggest that Stokes drift depresses the effect of strong winds on currents by intensifying turbulent *** layer depth(MLD)is distinctly increased by O(1)during typhoons due to SDP and can deepen by more than *** addition,the continuous effects of SDP on SST,current,and MLD at the after-typhoon stage indi-cate a hysteretic response between SDP and typhoon actions.

关键词： Stokes drift production Langmuir turbulence rurbulent mixing typhoon coupled model

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Uncertainties of landslide susceptibility prediction:influences of different study area scales and mapping unit scales

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International Journal of Coal Science & Technology 2024年第2期11卷 143-172页

作者： Faming Huang yu cao Wenbin Li Filippo Catani Guquan Song Jinsong Huang Changshi yu School of Civil Engineering and Architecture Nanchang UniversityNanchang 330031China Hebei International Joint Research Center for Remote Sensing of Agricultural Drought Monitoring/School of Land Science and Space Planning Hebei GEO UniversityShijiazhuang 050031China Department of Geosciences University of PadovaPaduaItaly Discipline of Civil Surveying and Environmental EngineeringPriority Research Centre for Geotechnical Science and EngineeringUniversity of NewcastleCallaghanNSWAustralia School of Information Engineering Nanchang UniversityNanchang 330031China

This study aims to investigate the effects of different mapping unit scales and study area scales on the uncertainty rules of landslide susceptibility prediction(LSP).To illustrate various study area scales,Ganzhou City in China,its eastern region(Ganzhou East),and Ruijin County in Ganzhou East were *** mapping unit scales are represented by grid units with spatial resolution of 30 and 60 m,as well as slope units that were extracted by multi-scale segmentation *** 3855 landslide locations and 21 typical environmental factors in Ganzhou City are first determined to create spatial datasets with ***,landslide susceptibility maps(LSMs)of Ganzhou City,Ganzhou East and Ruijin County are pro-duced using a support vector machine(SVM)and random forest(RF),*** LSMs of the above three regions are then extracted by mask from the LSM of Ganzhou City,along with the LSMs of Ruijin County from Ganzhou ***,LSMs of Ruijin at various mapping unit scales are generated in *** and landslide suscepti-bility indexes(LSIs)distribution are used to express LSP *** LSP uncertainties under grid units significantly decrease as study area scales decrease from Ganzhou City,Ganzhou East to Ruijin County,whereas those under slope units are less affected by study area *** course,attentions should also be paid to the broader representativeness of large study *** LSP accuracy of slope units increases by about 6%–10%compared with those under grid units with 30 m and 60 m resolution in the same study area's *** significance of environmental factors exhibits an averaging trend as study area scale increases from small to *** importance of environmental factors varies greatly with the 60 m grid unit,but it tends to be consistent to some extent in the 30 m grid unit and the slope unit.

关键词： Landslide susceptibility prediction Uncertainty analysis Study areas scales Mapping unit scales Slope units Random forest

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Spatiotemporal variation of land surface temperature and its driving factors in Xinjiang,China

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Journal of Arid Land 2024年第3期16卷 373-395页

作者： ZHANG Mingyu cao yu ZHANG Zhengyong ZHANG Xueying LIU Lin CHEN Hongjin GAO yu yu Fengchen LIU Xinyi College of Sciences Shihezi UniversityShihezi 832000China Key Laboratory of Oasis Town and Mountain-Basin System Ecology Xinjiang Production and Construction CorpsShihezi 832000China Yantai Institute of Coastal Zone Research Chinese Academy of SciencesYantai 264003China

Land surface temperature(LST) directly affects the energy balance of terrestrial surface systems and impacts regional resources, ecosystem evolution, and ecosystem structures. Xinjiang Uygur Autonomous Region is located at the arid Northwest China and is extremely sensitive to climate change. There is an urgent need to understand the distribution patterns of LST in this area and quantitatively measure the nature and intensity of the impacts of the major driving factors from a spatial perspective, as well as elucidate the formation mechanisms. In this study, we used the MOD11C3 LST product developed on the basis of Moderate Resolution Imaging Spectroradiometer(MODIS) to conduct regression analysis and determine the spatiotemporal variation and differentiation pattern of LST in Xinjiang from 2000 to 2020. We analyzed the driving mechanisms of spatial heterogeneity of LST in Xinjiang and the six geomorphic zones(the Altay Mountains, Junggar Basin, Tianshan Mountains, Tarim Basin, Turpan-Hami(Tuha) Basin, and Pakakuna Mountain Group) using geographical detector(Geodetector) and geographically weighted regression(GWR) models. The warming rate of LST in Xinjiang during the study period was 0.24℃/10a, and the spatial distribution pattern of LST had obvious topographic imprints, with 87.20% of the warming zone located in the Gobi desert and areas with frequent human activities, and the cooling zone mainly located in the mountainous areas. The seasonal LST in Xinjiang was at a cooling rate of 0.09℃/10a in autumn, and showed a warming trend in other seasons. Digital elevation model(DEM), latitude, wind speed, precipitation, normalized difference vegetation index(NDVI), and sunshine duration in the single-factor and interactive detections were the key factors driving the LST changes. The direction and intensity of each major driving factor on the spatial variations of LST in the study area were heterogeneous. The negative feedback effect of DEM on the spatial differentiation o

关键词： land surface temperature MOD11C3 climate change geographical detector(Geodetector) geographically weighted regression(GWR) source-sink effect Xinjiang

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Prediction of chemical short-range order in high-/medium-entropy alloys

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Journal of Materials Science & Technology 2024年第2期169卷 115-123页

作者： Pei-yu cao Jing Wang Ping Jiang yun-Jiang Wang Fu-Ping yuan Xiao-Lei Wu State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of ScienceBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Chemical short-range orders(CSROs),as the built-in sub-nanoscale entities in a high-/medium-entropy alloy(H/MEA),have aroused an ever-increasing *** multi-principal elements in an H/MEA to form a complex concentrated solution,a variety of sub-systems of species exist to induce the metastable ordered compounds as candidates for ultimate *** issues remain pending on the origin of CSROs as to how to judge if CSRO will form in an H/MEA and particularly,what kind of CSROs would be stably produced if there were multiple ***,the first-principles method,along with the proposed local formation energy calculation in allusion to the atomic-scale chemical heterogeneities,is used to predict the CSRO formation based on the mechanical stability,thermodynamic formation energy,and electronic *** simulations are detailed in an equiatomic ternary VCoNi MEA with three kinds of potential compounds,i.e.,L1_(1),L1_(2),and B2,in the face-centered cubic *** turns out that L1_(1)is stable but hard to grow up so as to become the final CSRO.L1_(1)is further predicted as CSROs in CrCoNi,but unable to form in FeCoNi and CrMnFeCoNi *** predictions are consistent with the experimental *** findings shed light on understanding the formation of *** method is applicable to other H/MEAs to design and tailor CSROs by tuning chemical species/contents and thermal processing for high performance.

关键词： Short-range order High-entropy alloy Microstructure First-principles calculation Gibbs free energy Local electronic density of states

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Development and validation of a nomogram model for predicting the risk of pre-hospital delay in patients with acute myocardial infarction

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World Journal of Cardiology 2024年第2期16卷 80-91页

作者： Jiao-yu cao Li-Xiang Zhang Xiao-Juan Zhou Department of Cardiology The First Affiliated Hospital of USTCDivision of Life Science and MedicineUniversity of Science and Technology of ChinaHefei 230001Anhui ProvinceChina

BACKGROUND Acute myocardial infarction(AMI)is a severe cardiovascular disease caused by the blockage of coronary arteries that leads to ischemic necrosis of the *** medical contact is critical for successful AMI treatment,and delays increase the risk of death for ***-hospital delay time(PDT)is a significant challenge for reducing treatment times,as identifying high-risk patients with AMI remains *** study aims to construct a risk prediction model to identify high-risk patients and develop targeted strategies for effective and prompt care,ultimately reducing PDT and improving treatment *** To construct a nomogram model for forecasting pre-hospital delay(PHD)likelihood in patients with AMI and to assess the precision of the nomogram model in predicting PHD *** A retrospective cohort design was employed to investigate predictive factors for PHD in patients with AMI diagnosed between January 2022 and September *** study included 252 patients,with 180 randomly assigned to the development group and the remaining 72 to the validation group in a 7:3 *** risk factors influencing PHD were identified in the development group,leading to the establishment of a nomogram model for predicting PHD in patients with *** model's predictive performance was evaluated using the receiver operating characteristic curve in both the development and validation *** Independent risk factors for PHD in patients with AMI included living alone,hyperlipidemia,age,diabetes mellitus,and digestive system diseases(P<0.05).A characteristic curve analysis indicated area under the receiver operating characteristic curve values of 0.787(95%confidence interval:0.716–0.858)and 0.770(95%confidence interval:0.660-0.879)in the development and validation groups,respectively,demonstrating the model's good discriminatory *** Hosmer–Lemeshow goodness-of-fit test revealed no statistically significant disparity between the an

关键词： Pre-hospital delay Acute myocardial infarction Risk prediction Nomogram

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细石叶技术的起源、二元分化及环境驱动因素

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人类学学报 2024年第3期43卷 355-366页

作者：仪明洁曹彧中国人民大学历史学院

在亚洲东北部地区，细石叶技术是旧石器时代晚期人类适应气候和环境的最关键因素之一。学术界围绕细石叶技术产生很多讨论，其中起源、技术演变及技术类型的区域分布是被关注的几个关键问题。细石叶技术可分为初始、成熟、简约几个技术... 详细信息

在亚洲东北部地区，细石叶技术是旧石器时代晚期人类适应气候和环境的最关键因素之一。学术界围绕细石叶技术产生很多讨论，其中起源、技术演变及技术类型的区域分布是被关注的几个关键问题。细石叶技术可分为初始、成熟、简约几个技术发展阶段，压制法的运用是细石叶技术成熟的关键，细小化的特点决定了各类细石叶使用功能上的区别并不显著。因而在实践层面上，细石叶技术的判定应重视石核和产品形态、技术生产流程、产品的使用意义、强调剥片策略分析，不应限定细石叶的剥制方法。末次盛冰期时，华北地区与中国东北地区、俄罗斯远东、日本北部等所构成的“北方区域”形成分别以船形石核、两面预制的楔形石核为主的二元分化格局，虽然出现过文化上的交叉融合，但是两个区存在以宽、窄楔形石核为主的现象，二元状态没有从根本上发生改变。细石叶技术的起源、成熟、分化与H3、H2、末次盛冰期几次冷事件间有较好的耦合关系，显示出环境驱动力仍然是导致史前人类生存策略变化的关键因素。

关键词：细石叶起源船形石核楔形石核环境驱动力

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