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Science China mathematics 2006年第11期49卷 1611-1624页

作者： BAOUENDI m S EBENFELT peter ROTHSCHILD Linda P Department of mathematics University of California at San Diego La JollaCA 92093-0112USA

It is shown that a germ of a holomorphic mapping sending a real-analytic generic submanifold of finite type into another is determined by its projection on the Segre variety of the target manifold. A necessary and sufficient condition is given for a germ of a mapping into the Segre variety of the target manifold to be the projection of a holomorphic mapping sending the source manifold into the target. An application to the biholomorphic equivalence problem is also given.

关键词： Segre variety, generic submanifold, Segre mappings, finite type, biholomorphic equivalence.

Semantic linking of complex properties,monitoring processes and facilities in web-based representations of the environment

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International Journal of Digital Earth 2016年第3期9卷 300-324页

作者： Adam m.Leadbetter peter N.Vodden marine Institute Co.GalwayIreland Centre for Ecology and Hydrology Lancaster Environment CentreLancasterUK

Where a virtual representation of the Earth must contain data values observed within the physical Earth system,data models are required that allow the integration of data across the silos of various Earth and environmental sciences *** a mapping between the well-defined terminologies of these silos is a stubborn *** paper presents a generalised ontology for use within Web 3.0 services,which builds on European Commission spatial data infrastructure *** presented ontology acknowledges that there are many complexities to the description of environmental properties which can be observed within the physical Earth *** ontology is shown to be flexible and robust enough to describe concepts drawn from a range of Earth science disciplines,including ecology,geochemistry,hydrology and *** paper also demonstrates the alignment and compatibility of the ontology with existing systems and shows applications in which the ontology may be deployed.

关键词： observable properties monitoring properties environmental monitoring facilities semantic web geospatial data integration

A Novel ABA Insensitive mutant of Lotus japonicus with a Wilty Phenotype Displays Unaltered Nodulation Regulation

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molecular Plant 2009年第3期2卷 487-499页

作者： Bandana Biswas Pick Kuen Chan peter m Gresshoff ARC Centre of Excellence for Integrative Legume Research The University of Queensland St Lucia Brisbane QId 4072 Australia

An ABA insensitive mutant, Beyma, was isolated in Lotus japonicus mG-20 from an EmS mutagenesis population using root growth inhibition to applied ABA as the screening criterion. （The name ＂Beyma＂ was taken from the Australian Aboriginal language, Wagiman, beyma, meaning ‘drying up＇.） The stable mutant that segregates as a dominant mendelian mutation is insensitive to ABA induced inhibition of germination, vegetative growth, stomatal opening, as well as nodulation. Tissue ABA levels were normal, suggesting a sensitivity rather than biosynthesis mutation. It is slow-growing （50-70% of wild-type mG-20） and has a near-constitutive wilty phenotype associated with its inability to regulate stomatal opening. Whilst showing a wide range of ABA insensitive phenotypes, Beyma did not show alteration of nodule number control, as, in the absence of added ABA, the number and patterning （but not size） of nodules formed in the mutant were similar to that of mG-20. Split root experiments on mG-20 showed that application of ABA on one side of the root inhibited nodulation locally but not systemically. We propose that ABA is not involved directly in systemic autoregulation of nodulation （AON）.

关键词： hormone biology water relations genetics development symbiosis legume.

The genetics and biology of KRAS in lung cancer

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Chinese Journal of Cancer 2013年第2期32卷 63-70页

作者： peter m.K.Westcott minh D.To Pharmaceutical Sciences and Pharmacogenomics Program University of California SanFrancisco Helen Diller Comprehensive Cancer Center University of California SanFrancisco Thoracic Oncology Program Department of SurgeryUniversity of California SanFrancisco

mutational activation of KRAS is a common oncogenic event in lung cancer and other epithelial cancer *** to develop therapies that counteract the oncogenic effects of mutant KRAS have been largely unsuccessful,and cancers driven by mutant KRAS remain among the most refractory to available *** undertaken over the past decades have produced a wealth of information regarding the clinical relevance of KRAS mutations in lung *** Kras-driven mouse models of cancer,together with cellular and molecular studies,have provided a deeper appreciation for the complex functions of KRAS in ***,a much more thorough understanding of these complexities is needed before clinically effective therapies targeting mutant KRAS-driven cancers can be achieved.

关键词： RAS基因肺癌生物学遗传学基因突变致癌作用临床意义小鼠模型

metabolomic, Transcriptional, Hormonal, and Signaling Cross-Talk in Superroot2

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molecular Plant 2010年第1期3卷 192-211页

作者： marc morant Claus Ekstrom peter Ulvskov Charlotte Kristensen mats Rudemo Carl Erik Olsen Jorgen hansen Kirsten Jorgensena Bodil Jorgensen Birger Lindberg moilera Soren Bak Plant Biochemistry Laboratory Department of Plant Biology and Biotechnology University of Copenhagen 40 Thorvaldsensvej DK-1871 FrederiksbergC Copenhagen Denmark Center for molecular Plant Physiology University of Copenhagen. DK-1871 Frederiksberg C Copenhagen Denmark Department of Natural Sciences University of Copenhagen DK-1871 Frederiksberg C Copenhagen Denmark VKR research centre 'Pro-Active Plants' Plant Biochemistry Laboratory Department of Plant Biology and Biotechnology University of Copenhagen DK-1871 Frederiksberg C Copenhagen Denmark Evolva A/S Bulowsvej 25 DK-1870 Frederiksberg C Copenhagen Denmark Center for Applied Bioinformatics at LIFE University of Copenhagen 40 Thorvaldsensvej DK-1871 Frederiksberg C Copenhagen Denmark

Auxin homeostasis is pivotal for normal plant growth and development. The superroot2 （sur2） mutant was initially isolated in a forward genetic screen for auxin overproducers, and SUR2 was suggested to control auxin conju- gation and thereby regulate auxin homeostasis. However, the phenotype was not uniform and could not be described as a pure high auxin phenotype, indicating that knockout of CYP83B1 has multiple effects. Subsequently, SUR2 was identified as CYP83B1, a cytochrome P450 positioned at the metabolic branch point between auxin and indole glucosinolate metabolism. To investigate concomitant global alterations triggered by knockout of CYP83B1 and the countermeasures chosen by the mutant to cope with hormonal and metabolic imbalances, 10-day-old mutant seedlings were characterized with respect to their transcriptome and metabolome profiles. Here, we report a global analysis of the sur2 mutant by the use of a combined transcriptomic and metabolomic approach revealing pronounced effects on several metabolic grids including the intersection between secondary metabolism, cell wall turnover, hormone metabolism, and stress responses. metabolic and transcriptional cross-talks in sur2 were found to be regulated by complex interactions between both positively and negatively acting transcription factors. The complex phenotype of sur2 may thus not only be assigned to elevated levels of auxin, but also to ethylene and abscisic acid responses as well as drought responses in the absence of a water deficiency. The delicate balance between these signals explains why minute changes in growth conditions may result in the non-uniform phenotype. The large phenotypic variation observed between and within the different surveys may be reconciled by the complex and intricate hormonal balances in sur2 seedlings decoded in this study.

关键词： Abiotic/environmental stress hormonal regulation metabolomics secondary metabolism/natural products transcriptome analysis development.

On some aspects of minimum redundancy maximum relevance feature selection

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Science China(Information Sciences) 2020年第1期63卷 89-103页

作者： peter BUGATA peter DROTAR Intelligent Information Systems Lab Technical University of Kosice

The feature selection is an important challenge in many areas of machine learning because it plays a crucial role in the interpretations of machine-driven decisions. There are various approaches to the feature selection problem and methods based on the information theory comprise an important ***, the minimum redundancy maximum relevance(m RmR) feature selection is undoubtedly the most popular one with widespread application. In this paper, we prove in contrast to an existing finding that the m RmR is not equivalent to max-Dependency criterion for first-order incremental feature selection. We present another form of equivalence leading to a generalization of m RmR feature selection. Additionally,we compare several feature selection methods based on m RmR, max-Dependency, and feature ranking,employing different measures of dependency. The results on high-dimensional real-world datasets show that the distance correlation is the suitable measure for dependency-based feature selection methods. The results also indicate that the max-Dependency incremental algorithm combined with distance correlation appears to be a promising feature selection approach.

关键词： big data information theory feature selection dimensionality reduction minimum redundancy maximum relevance m RmR

Waist circumference thresholds and cardiorespiratory fitness

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Journal of Sport and Health Science 2019年第1期8卷 17-22页

作者： Sindre m.Dyrstad Elisabeth Edvardsen Bj?rge H.hansen Sigmund A.Anderssen Department of Education and Sport Science University of Stavanger Department of Sports medicine Norwegian School of Sport Sciences Department of Pulmonary medicine Oslo University Hospital

Purpose: This study's purpose was to examine whether established risk categories of waist circumference(WC)—normal, high risk, and very high health risk—reflected significant differences in cardiorespiratory fitness(CRF) and physical activity(PA) ***: CRF was directly measured as maximal oxygen uptake during a progressive graded treadmill test to exhaustion in 722 individuals(349 women) aged 20à85 years. WC was measured between the lower rib and the iliac crest. Objectively measured PA was assessed using an ***: men in the normal risk group(WC m) had a 31% higher CRF and 43% higher level of moderate-to-vigorous PA than men in the very high risk group(with a WC > 102 cm). Corresponding numbers for women within normal(WC m) and very high risk group(WC > 88 cm) were 25% and 18%(p men(r = ?0.68), and a moderate correlation for women(r = ?0.49; p m increase in WC, CRF was reduced by 0.48 and 0.27 mL/kg/min in men and women,respectively(p mmended WC thresholds for abdominal obesity reflected significant differences in CRF for both men and women, and could serve as a useful instrument for estimating health-related differences in CRF.

关键词： Abdominal obesity Fit fat maximal oxygen uptake Obesity Public health Waist circumference

A generic and extensible model for the martensite start temperature incorporating thermodynamic data mining and deep learning framework

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Journal of materials Science & Technology 2022年第33期128卷 31-43页

作者： Chenchong Wang Kaiyu Zhu peter Hedström Yong Li Wei Xu State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Department of materials Science and Engineering KTH Royal Institute of TechnologyStockholm 10044Sweden

The martensite start temperature is a critical parameter for steels with metastable *** numerous models have been developed to predict the martensite start(ms)temperature,the complexity of the martensitic transformation greatly limits their performance and *** this work,we apply deep data mining of thermodynamic calculations and deep learning to develop a generic model for *** data mining was used to establish a hierarchical database with three levels of ***,a convolutional neural network model,which can accurately treat the hierarchical data structure,was used to obtain the final *** integrating thermodynamic calculations,traditional machine learning and deep learning modeling,the final predictor model shows excellent generalizability and extensibility,*** performance both within and beyond the composition range of the original *** effects of 15 alloying elements were considered successfully using the proposed *** work suggests that,with the help of deep data mining considering the physical mechanisms,deep learning methods can partially mitigate the challenge with limited data in materials science and provide a means for solving complex problems with small databases.

关键词： martensite transformation Data mining Deep learning Extensibility Small-sample problem

干旱绿洲区包气带土壤盐分分布特征及运移机制——以新疆焉耆盆地为例

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地质论评 2024年第5期70卷 1857-1872页

作者：陈振宇赵禹白金赵寒森梁楠刘拓姚远中国地质调查局西安地质调查中心(西北地质科技创新中心) 西安710054 中国地质调查局造山带地质研究中心西安710054 中国地质调查局干旱半干旱区地下水与生态重点实验室西安710054

土壤盐渍化问题严重制约着我国干旱—半干旱区农业可持续高质量发展,了解包气带土壤盐分离子分布特征及垂向运移机制对科学防治土壤盐渍化具有重要意义。通过精细化采集新疆焉耆盆地2 m深度剖面土壤,测定样品机械组成和8种盐分离子含量... 详细信息

土壤盐渍化问题严重制约着我国干旱—半干旱区农业可持续高质量发展,了解包气带土壤盐分离子分布特征及垂向运移机制对科学防治土壤盐渍化具有重要意义。通过精细化采集新疆焉耆盆地2 m深度剖面土壤,测定样品机械组成和8种盐分离子含量,计算土壤颗粒分形维数,采用统计学方法分析包气带土壤盐分离子垂向分布特征,对包气带土壤质地与水盐运移间的关系进行探讨。结果表明,博湖剖面包气带土壤主要为非盐渍土,土壤盐分主要受开都河下游地下水水化学类型和矿化度控制,阴阳离子比值约为2∶5,盐分类型主要为Ca^(2+)—HCO_(3)^(2-)和Na^(+)—SO_(4)^(2-)型;焉耆剖面包气带土壤普遍为重度盐渍土,土壤盐分受到开都河下游地下水水化学类型和自身包气带盐分的综合影响,阴阳离子比值约为1∶2,盐分类型主要为Ca^(2+)—SO_(4)^(2-)型和Na^(+)—Cl^(-)型。土壤分形维数和黏粒含量之间显著正相关,与砂粒含量显著负相关,包气带土壤盐分与分形维数间相关性不明显,主要受到土壤粒径组成及其所处深度等综合作用的影响。博湖包气带土壤质地由表层至深部逐渐变粗,盐分含量呈现出在0~80 cm深度的表层和125~200 cm的底部波动大,80~125 cm稳定的变化趋势,盐分离子主要聚集在约30 cm深度粉质黏壤土与粉质黏土层的交界处。土壤盐分运移大致可划分为交互作用段(0~80 cm)、平衡段(80~125 cm)和地下水扰动段(125~200 cm)3个部分,蒸发作用影响深度约80 cm。焉耆包气带土壤质地由表层至深部逐渐变细,随深度的增加,盐分含量和波动程度均逐渐减小,盐分离子主要聚集在0~10 cm表土层。盐分运移大致可划分为盐分离子上升段(0~120 cm)和平衡段(120~200 cm)两个部分,蒸发作用影响深度约为120 cm。上细下粗型的包气带土壤质地组成是抑制土壤盐渍化较为理想的分布模式,对于焉耆剖面类型可先采取灌溉压盐,然后进行约40 cm深度的翻耕,博湖剖面类型可直接采取50 cm左右深度的深耕,一定程度上能够抑制盐渍化的发生。

关键词：包气带土壤质地盐分离子分形维数运移机制焉耆盆地

A comparison of conventional and computer-assisted semen analysis.（CRISmAS software） using samples from 166 young Danish men

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Asian Journal of Andrology 2011年第3期13卷 453-458,513页

作者： Anne Vested Cecilia H Ramlau-hansen Jens P Bonde Ane m Thulstrup Susanne L Kristensen Gunnar Toft Danish Ramazzini Center Department of Occupational Medicine Aarhus University Hospital DK-8000 Aarhus C Denmark Department of Occupational and Environmental medicine Copenhagen University Hospital Bispebjerg DK-2400 Copenhagen NV Denmark

The aim of the present study was to compare assessments of sperm concentration and sperm motility analysed by conventional semen analysis with those obtained by computer-assisted semen analysis （CASA）（Copenhagen Rigshospitalet Image House Sperm motility Analysis System （CRISmAS） 4.6 software） using semen samples from 166 young Danish men. The CRISmAS software identifies sperm concentration and classifies spermatozoa into three motility categories. To enable comparison of the two methods, the four motility stages obtained by conventional semen analysis were, based on their velocity classifications, divided into three stages, comparable to the three CRISmAS motility categories： rapidly progressive （A）, slowly progressive （B） and non-progressive （C＋ D）. Differences between the two methods were large for all investigated parameters （P〈0.001）. CRISmAS overestimated sperm concentration and the proportion of rapidly progressive spermatozoa and, consequently, underestimated the percentages of slowly progressive and non-progressive spermatozoa, compared to the conventional method. To investigate whether results drifted according to time of semen analysis, results were pooled into quarters according to date of semen analysis. CRISmAS motility results appeared more stable over time compared to the conventional analysis; however, neither method showed any trends. Apparently, CRISmAS CASA results and results from the conventional method were not comparable with respect to sperm concentration and motility analysis. This needs to be accounted for in clinics using this software and in studies of determinants of these semen characteristics.

关键词： computer-assisted semen analysis reproduction semen analysis sperm concentration sperm motility