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    题名 作者 年代 出处 被引量
1Deep forest显示文摘Current deep-learning models are mostly built upon neural networks, i.e. multiple layers of parameterized differentiable non-linear modules that can be trained by backpropagation. In this paper, we explore the possibility of building deep models based on non-differentiable modules such as decision trees. After a discussion about the mystery behind deep neural networks, particularly by contrasting them with shallow neural networks and traditional machine-learning techniques such as decision trees and boosting machines,we conjecture that the success of deep neural networks owes much to three characteristics, i.e.layer-by-layer processing, in-model feature transformation and sufficient model complexity. On one hand,our conjecture may offer inspiration for theoretical understanding of deep learning; on the other hand, to verify the conjecture, we propose an approach that generates deep forest holding these characteristics. This is a decision-tree ensemble approach, with fewer hyper-parameters than deep neural networks, and its model complexity can be automatically determined in a data-dependent way. Experiments show that its performance is quite robust to hyper-parameter settings, such that in most cases, even across different data from different domains, it is able to achieve excellent performance by using the same default setting. This study opens the door to deep learning based on non-differentiable modules without gradient-based adjustment, and exhibits the possibility of constructing deep models without backpropagation.Zhi-Hua Zhou Ji Feng 2019National Science Review2019,6,1:52
2Recent advances and perspectives of nucleic acid detection for coronavirus显示文摘The recent pneumonia outbreak caused by a novel coronavirus(SARS-CoV-2)is posing a great threat to global public health.Therefore,rapid and accurate identification of pathogenic viruses plays a vital role in selecting appropriate treatments,saving people's lives and preventing epidemics.It is important to establish a quick standard diagnostic test for the detection of the infectious disease(COVID-19)to prevent subsequent secondary spread.Polymerase chain reaction(PCR)is regarded as a gold standard test for the molecular diagnosis of viral and bacterial infections with high sensitivity and specificity.Isothermal nucleic acid amplification is considered to be a highly promising candidate method due to its fundamental advantage in quick procedure time at constant temperature without thermocycler opera-tion.A variety of improved or new approaches also have been developed.This review summarizes the currently available detection methods for coronavirus nucleic acid.It is anticipated that this will assist researchers and clinicians in developing better techniques for timely and effective detection of coro-navirus infection.Minzhe Shen Ying Zhou Jiawei Ye Abdu Ahmed Abdullah AL-maskri Yu Kang Su Zeng Sheng Cai 2020Journal of Pharmaceutical Analysis2020,10,2:27
3CURVILINEAR PATHS AND TRUST REGION METHODS WITH NONMONOTONIC BACK TRACKING TECHNIQUE FOR UNCONSTRAINED OPTIMIZATION显示文摘In this paper we modify type approximate trust region methods via two curvilinear paths for unconstrained optimization. A mired strategy using both trust region and line search techniques is adopted which switches to back tracking steps when a trial step produced by the trust region subproblem is unacceptable. We give a series of properties of both optimal path and modified gradient path. The global convergence and fast local convergence rate of the proposed algorithms are established under some reasonable conditions. A nonmonotonic criterion is used to speed up the convergence progress in some ill-conditioned cases.De-tong Zhu (Department of Mathematics, Shanghai Normal University, Shanghai 200234, China) 2001Journal of Computational Mathematics2001,19,3:26
4GENERALIZED DIFFERENCE METHODS ON ARBITRARYQUADRILATERAL NETWORKS显示文摘1.IntroductionConsidertheboundaryvalueproblemofthePoissonequationwherefiisaconvexpolygonregon;r^OfftheboundaryofOandf(x,y)aknownfunctiononfi.Thegeneralizeddifferencemethodsonquadrilateralnetworksforellipticequationsareproposedin[11],'wheretheconverge...Yong-hai Li Rong-hua Li(Institute of Mathematics, Jinn University, Changchun 130023, China) 1999Journal of Computational Mathematics1999,17,6:22
5伪双曲型积分-微分方程的H^1-Galerkin混合元法误差估计显示文摘1引言考虑如下一类具有Lipschitz连续边界(?)Ω的凸有界区域Ω上的伪双曲型积分微分方程其中Ω(?)Rd,(d=1,2,3)J=(0,T],对于固定的T,0刘洋 李宏 何斯日古楞 2010高等学校计算数学学报2010,32,1:21
6Precision surgical approach with lymph-node dissection in early gastric cancer显示文摘The gravest prognostic factor in early gastric cancer is lymph-node metastasis,with an incidence of about 10% overall. About two-thirds of early gastric cancer patients can be diagnosed as node-negative prior to treatment based on clinicpathological data. Thus, the tumor can be resected by endoscopic submucosal dissection. In the remaining third, surgical resection is necessary because of the possibility of nodal metastasis. Nevertheless, almost all patients can be cured by gastrectomy with D1+ lymph-node dissection. Laparoscopic or robotic gastrectomy has become widespread in East Asia because perioperative and oncological safety are similar to open surgery. However, after D1+ gastrectomy,functional symptoms may still result. Physicians must strive to minimize postgastrectomy symptoms and optimize long-term quality of life after this operation.Depending on the location and size of the primary lesion, preservation of the pylorus or cardia should be considered. In addition, the extent of lymph-node dissection can be individualized, and significant gastric-volume preservation can be achieved if sentinel node biopsy is used to distinguish node-negative patients.Though the surgical treatment for early gastric cancer may be less radical than in the past, the operative method itself seems to be still in transition.Shinichi Kinami Naohiko Nakamura Yasuto Tomita Takashi Miyata Hideto Fujita Nobuhiko Ueda Takeo Kosaka 2019World Journal of Gastroenterology2019,25,14:21
7Safety Research in Traditional Chinese Medicine: Methods, Applications, and Outlook显示文摘Traditional Chinese medicine (TCM) is a medical system that has collected and summarized abundant clinical experience over its long history of more than 2000 years. However, the frequent occurrence of TCM-induced adverse reactions has hindered the modernization and internationalization of TCM, while attracting increasing attention from around the world. Unlike chemical drugs and biological agents, the difficulties involved in research on the toxicity and safety of TCM mainly include the complexity of its components and the unpredictability of drug–body interactions. Much of TCM, which has overall therapeutic effects, has the typical mechanisms of multiple components, multiple pathways, and multiple targets. While considering the gradualness and unpredictability of TCM toxicity, the ambiguity of toxicants and safe dosage, and individual differences during long-term TCM administration, we have systematically established key techniques for the toxicity assessment of TCM. These techniques mainly include TCM toxicity discovery in an early phase, based on a combination of drug toxicology genomics and metabolomics;methods to identify dose–toxicity relationships in TCM;and integrated techniques for the exploration of TCM interactions, such as fast-screening tests based on drug-metabolizing enzymes and receptor pathways. In particular, we have developed a new technical system for TCM safety evaluation using molecular toxicology, which has been validated well in research on TCM compatibility contraindication, quality control, and allergen discovery. The application of this key technical platform is introduced here in detail. This application includes model organisms, toxicant biomarkers, a magnetic suspension technique, and the application of network toxicology and computational toxicology in research on the toxicity of Fructus toosendan, Semen cassiae, Polygonum multiflorum, and Fructus psoraleae.Yue Gao Aihua Liang Xiaohui Fan Limin Hu Feiran Hao Yubo Li 2019Engineering2019,5,1:19
8Effect of wide-narrow row arrangement in mechanical pot-seedling transplanting and plant density on yield formation and grain quality of japonica rice显示文摘Mechanical pot-seedling transplanting is an innovatively developed transplanting method that has the potential to replace mechanical carpet-seedling transplanting. However, the initial pot-seedling transplanting machine lacked optimized density spacing and limited yield potential for japonica rice. Therefore, ascertaining the optimized density by wide-narrow rows and the appropriate transplanting method for yield formation and grain quality of japonica rice is of great importance for high-quality rice production. Field experiments were conducted using two japonica rice cultivars Nanjing 9108 and Nanjing 5055 under three transplanting methods in 2016 and 2017: mechanical pot-seedling transplanting with wide-narrow row(K, average row spacing of 30 cm);equidistant row(D, 33 cm×12 cm);and mechanical carpet-seedling transplanting(T, 30 cm×12.4 cm). In addition, five different density treatments were set in K(K1–K5, from 18.62×10~4 to 28.49×10~4 hills ha^(–1)). The results showed that the highest yield was produced by a planting density of 26.88×104 hills ha^(–1) in mechanical pot-seedling transplanting with wide-narrow row with a greater number of total spikelets that resulted from significantly more panicles per area and slightly more grain number per panicle, as compared with equidistant row, and yield among density in wide-narrow row showed a parabolic trend. Compared with mechanical carpet-seedling transplanting, the treatment of the highest yield increased yield significantly, which was mainly attributed to the larger sink size with improved filled-grain percentage and grain weight, higher harvest index, and increased total dry matter accumulation, especially the larger amount accumulated from heading stage to maturity stage. With the density in wide-narrow row decreasing, processing quality, appearance quality, and nutrition quality were all improved, whereas amylose content and the taste value were decreased. Compared with mechanical carpet-seedling transplanting, mechanical pot-seedling transplanting improved processing quality and nutrition quality, but decreased amylose content and deteriorated appearance quality. These results suggested that mechanical pot-seedling transplanting with wide-narrow row coupling produced a suitable planting density of 26.88×10~4 hills ha^(–1) and may be an alternative approach to improving grain yield and quality for japonica rice.HU Qun JIANG Wei-qin QIU Shi XING Zhi-peng HU Ya-jie GUO Bao-wei LIU Guo-dong GAO Hui ZHANG Hong-cheng WEI Hai-yan 2020Journal of Integrative Agriculture2020,19,5:19
9小麦茎基腐病苗期快速接种鉴定方法研究显示文摘为建立一种小麦茎基腐病快速接种鉴定方法,以扬麦158、Sunco、Kennedy为材料,采用4种接种方法评价了小麦苗期茎基腐病抗性鉴定效果,并以扬麦158/CI12633群体验证了所采纳的最优接种方法的致病效果。结果表明:采用苗期棉球接种法小麦品种间抗性差异明显,操作方便,发病稳定性等方面优于其他方法。因此,小麦茎基腐病抗性种质资源筛选时可以将棉球接种法作为鉴定评价的首选方法。霍燕 张鹏 任丽娟 姚金保 马鸿翔 2010江西农业学报2010,22,8:15
10基于β-微管蛋白基因部分序列探讨灵芝属菌株的亲缘关系显示文摘PCR分别扩增了38个灵芝属菌株的β-微管蛋白基因片段,并对PCR产物进行序列测定,得到419bp的一段核苷酸系列。根据MEGA2.1软件中的neighbour-joiningmethods对上述序列进行聚类分析,结果所有供试菌株被分成9个聚类组。中国栽培灵芝菌株分布于6个聚类组,其中树舌亚属、紫芝组的菌株各自聚成一组,灵芝组的菌株分成四组,但大部分灵芝组菌株均聚于同一组,这表明树舌亚属、紫芝组和灵芝组间的遗传差异较大,灵芝组内虽然存在着一定的遗传差异,但总体上亲缘关系比较近,遗传多样性并不丰富。同时,序列分析的结果显示,β-tubulin基因序列在第三位密码子和内含子部位有高的碱基替换率,这些变异提供了丰富的系统发育信息,提示β-tubulin基因适合于灵芝属菌株的亲缘关系研究。苏春丽 唐传红 张劲松 潘迎捷 2006菌物学报2006,25,3:15
11Research advances in the detection of miRNA显示文摘MicroRNAs (miRNAs) are a family of endogenous, small (approximately 22 nucleotides in length), noncoding, functional RNAs. With the development of molecular biology, the research of miRNA biological function has attracted significant interest, as abnormal miRNA expression is identified to contribute to serious human diseases such as cancers. Traditional methods for miRNA detection do not meet current demands. In particular, nanomaterial-based methods, nucleic acid amplification-based methods such as rolling circle amplification (RCA), loop-mediated isothermal amplification (LAMP), strand-displacement amplification (SDA) and some enzyme-free amplifications have been employed widely for the highly sensitive detection of miRNA. MiRNA functional research and clinical diagnostics have been accelerated by these new techniques. Herein, we summarize and discuss the recent progress in the development of miRNA detection methods and new applications. This review will provide guidelines for the development of follow-up miRNA detection methods with high sensitivity and specificity, and applicability to disease diagnosis and therapy.Jiawei Ye Mingcheng Xu Xueke Tian Sheng Cai Su Zeng 2019Journal of Pharmaceutical Analysis2019,9,4:15
12A SCALED CENTRAL PATH FOR LINEAR PROGRAMMING显示文摘Interior point methods are very efficient methods for solving large scale linear programming problems. The central path plays a very important role in interior point methods. In this paper we propose a new central path, which scales the variables. Thus it has the advantage of forcing the path to have roughly the same distance from each active constraint boundary near the solution.Ya-xiang Yuan (State Key Laboratory of Scientific and Engineering Computing, Institute of Computational Mathematics and Scientific/Engineering Computing Chinese Academy of Sciences, Beijing 100080, China) 2001Journal of Computational Mathematics2001,19,1:14
13振荡型波浪能转换装置中两种优化方法研究显示文摘该文基于线性波理论,从载体在波浪中的运动方程出发,以两种不同的优化角度推导了波能装置输出能量最大时的表现形式,最后以圆柱体作为波浪能转换的载体分析了两者方法的差异。数值计算表明在同一水深下,波能装置浮体的水线面决定了波能装置最优转换效率的趋势,而吃水深度决定了波能装置可达到的最大转换效率;对波能装置参数优化后运动在共振点的波能装置其转换效率并不是最大,而优化后的最大转换效率并不发生在共振点上。吴必军 吝红军 游亚戈 冯波 盛松伟 2010太阳能学报2010,31,6:12
14Derwent Innovations Index数据库的主要特点及其检索方法显示文摘Derwent Innovations Index收录全面的专利文献,可以综合检索世界各国的专利文献,包括世界各地化学、电子电气以及工程技术领域内综合全面的发明信息,本文介绍该系统的特点、检索途径与方法等。郑伟 2009中国索引2009,7,1:12
15TOTAL GENERALIZED MINIMUM BACKWARD ERROR ALGORITHM FOR SOLVING NONSYMMETRIC LINEAR SYSTEMS显示文摘This paper extendes the results by E.M. Kasenally[7] on a Generalized Minimum Backward Error Algorithm for nonsymmetric linear systems Ax=b to the problem in which pertubations are simultaneously permitted on A and b. The approach adopted by Kasenally has been to view the approximate solution as the exact solution to a perturbed linear system in which changes are permitted to the matrix A only. The new method introduced in this paper is a Krylov subspace iterative method which minimizes the norm of the perturbations to both the observation vector b and the data matrix A and has better performance than the Kasenally’s method and the restarted GMRES method[12]. The minimization problem amounts to computing the smallest singular value and the corresponding right singular vector of a low-order upper-Hessenberg matrix. Theoratical properties of the algorithm are discussed and practical implementation issues are considered.The numerical examples are also given.Zhi-hao Cao (Dearptment of Mathematics, Fudan University, Shanghai 200433, China) 1998Journal of Computational Mathematics1998,16,6:12
16Development as adaptation: Framing and measuring urban resilience in Beijing显示文摘As part of their efforts to cope with climate change, many municipal governments have considered the improvement of urban resilience as an important strategy. In this study, we take the megacity of Beijing as an example and conduct a mixed-methods research using both qualitative and quantitative methods to explore linkage between resilience and development. First, based on expert consultation, we develop an analytical framework and propose reference indicators for measuring urban resilience. Second, we conduct an exploratory factor analysis to justify this analytical framework and rank the urban resilience index for 16 districts in Beijing. Results indicate that urban resilience at the district level is distinguished by the characteristics of the district's functional zones. This implies that the development focus of each district influences the driving factors of urban resilience. This article provides evidence that development and adaptation can be complementary. We showcase in Beijing that urban generic resilience is highly dependent on socio-economic development and urbanization, whereas specific resilience to climatic extremes can be attributed to natural endowment and environmental investment. In conclusion, using this study's findings as a guideline, mega-cities are urged to adopt development-oriented adaptation as a strategy of proactive risk planning in the context of rapid urbanization and global climate change in China.ZHENG Yan XIE Xin-Lu LIN Chen-Zhen WANG Mou HE Xiao-Jia 2018Advances in Climate Change Research2018,9,4:11
17Review on fate of chlorine during thermal processing of solid wastes显示文摘Chlorine(Cl) is extensively present in solid wastes, causing significant problems during the thermal conversion of waste to energy or fuels, by combustion, gasification or pyrolysis.This paper introduces the analytical methods for determining the Cl content in solid materials and presents the concentrations of Cl in various types of wastes, as reported in literature. Then, it provides a comprehensive analysis on the Cl emission behavior and Cl species formed during the thermal processing of the inorganic and organic Cl sources. The challenges resulted from the reactions between the formed Cl species and the ferrous metals, the heavy metals and the organic matters are summarized and discussed, e.g., high temperature corrosion, heavy metal evaporation and dioxin formation. The quality degradation of products(oil, char and syngas) by Cl is analyzed. Finally, the available controlling methods of Cl emission, including pre-treatment(water washing, sorting,microwave irradiation and stepwise pyrolysis) and in-furnace(absorbents, co-treatment and catalysts) methods are assessed.Peng Lu Qunxing Huang A.C.(Thanos) Bourtsalas Nickolas J.Themelis Yong Chi Jianhua Yan 2019Journal of Environmental Sciences2019,31,4:11
18A Survey of Multi-robot Regular and Adversarial Patrolling显示文摘Multi-robot systems can be applied to patrol a concerned environment for security purposes.According to different goals,this work reviews the existing researches in a multi-robot patrolling field from the perspectives of regular and adversarial patrolling.Regular patrolling requires robots to visit important locations as frequently as possible and a series of deterministic strategies are proposed,while adversarial one focuses on unpredictable robots’moving patterns to maximize adversary detection probability.Under each category,a systematic survey is done including problem statements and modeling,patrolling objectives and evaluation criteria,and representative patrolling strategies and approaches.Existing problems and open questions are presented accordingly.Li Huang MengChu Zhou Kuangrong Hao Edwin Hou 2019IEEE/CAA Journal of Automatica Sinica2019,6,4:10
19Helicobacter pylori:a foodborne pathogen?显示文摘Helicobacter pylori(H. pylori) is an organism that is widespread in the human population and is sometimes responsible for some of the most common chronic clinical disorders of the upper gastrointestinal tract in humans, such as chronic-active gastritis, duodenal and gastric ulcer disease, low-grade B-cell mucosa associated lymphoid tissue lymphoma of the stomach, and gastric adenocarcinoma, which is the third leading cause of cancer death worldwide. The routes of infection have not yet been firmly established, and different routes of transmission have been suggested, although the most commonly accepted hypothesis is that infection takes place through the faecal-oral route and that contaminated water and foods might play an important role in transmission of the microorganism to humans. Furthermore, several authors have considered H. pylori to be a foodborne pathogen because of some of its microbiological and epidemiological characteristics. H. pylori has been detected in drinking water, seawater, vegetables and foods of animal origin. H. pylori survives in complex foodstuffs such as milk, vegetables and ready-to-eat foods. This review article presents an overview of the present knowledge on the microbiological aspects in terms of phenotypic characteristics and growth requirements of H. pylori, focusing on the potential role that foodstuffs and water may play in the transmission of the pathogen to humans and the methods successfully used for the detection of this microorganism in foodstuffs and water.Nicoletta C Quaglia Angela Dambrosio 2018World Journal of Gastroenterology2018,24,31:10
20Gastric leptomeningeal carcinomatosis: Multi-center retrospective analysis of 54 cases显示文摘AIM: To identify the clinical features and outcomes of infrequently reported leptomeningeal carcinomatosis (LMC) of gastric cancer.METHODS: We analyzed 54 cases of cytologically confirmed gastric LMC at four institutions from 1994 to 2007.RESULTS: The male-to-female ratio was 32:22, and the patients ranged in age from 28 to 78 years (median,48.5 years). The majority of patients had advanced disease at initial diagnosis of gastric cancer. The clini-cal or pathologic tumor, node and metastasis stage ofthe primary gastric cancer wasin 38 patients (70%).The median interval from diagnosis of the primarymalignancy to the diagnosis of LMC was 6.3 mo, rang-ing between 0 and 73.1 mo. Of the initial endoscopic f indings for the 45 available patients, 23 (51%) of the patients were Bormann typeand 15 (33%) patientswere Bormann type. Pathologically, 94% of cases proved to be poorly differentiated adenocarcinomas. Signet ring cell component was also observed in 40% of patients. Headache (85%) and nausea/vomiting (58%) were the most common presenting symptoms of LMC. A gadolinium-enhanced magnetic resonance imaging was conducted in 51 patients. Leptomeningeal enhancement was noted in 45 cases (82%). Intrathecal (IT) chemotherapy was administered to 36 patients-primarily methotrexate alone (61%), but also in combi-nation with hydrocortisone/± Ara-C (39%). The median number of IT treatments was 7 (range, 1-18). Concomitant radiotherapy was administered to 18 patients, and concomitant chemotherapy to seven patients. Sev-enteen patients (46%) achieved cytological negative conversion. Median overall survival duration from the diagnosis of LMC was 6.7 wk (95% CI: 4.3-9.1 wk). In the univariate analysis of survival duration, hemoglobin, IT chemotherapy, and cytological negative conversion showed superior survival duration (P = 0.038, P = 0.010, and P = 0.002, respectively). However, in our multivariate analysis, only cytological negative conversion was predictive of relatively longer survival duration (3.6, 6.7 and 14.6 wk, P = 0.030, RR: 0.415, 95% CI: 0.188-0.918).CONCLUSION: Although these patients had a fatal clinical course, cytologic negative conversion by IT chemotherapy may improve survival.Sung Yong Oh Su-Jin Lee Jeeyun Lee Suee Lee Sung-Hyun Kim Hyuk-Chan Kwon Gyeong-Won Lee Jung Hun Kang In Gyu Hwang Joung-Soon Jang Ho Yeong Lim Young Suk Park Won Ki Kang Hyo-Jin Kim 2009World Journal of Gastroenterology2009,15,40:10
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