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HUITWU： An Efficient Algorithm for High-Utility Itemset Mining in Transaction Databases

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Journal of Computer Science & Technology 2016年第4期31卷 776-786页

作者： shi-Ming guo Hong Gao School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China

Mining high-utility itemsets （HUIs） from a transaction database refers to the discovery of itemsets with high utilities like profits. Most of existing studies discover HUIs from a transaction database in two phases. In phase 1, different overestimation methods are applied to calculate the upper bounds of the utilities of itemsets. Since the overestimated utilities of itemsets are adopted, the itemsets whose overestimated utilities are no less than a user-specified threshold are selected as candidate HUIs, and they are verified by scanning the database one more time in phase 2. However, a large number of candidate HUIs incur two problems： 1） it requires excessive memory to store these candidates; 2） it needs a large amount of running time to calculate their exact utilities. Vertical data format has been applied to mine HUIs recently. However this kind of method cannot deal with transactions with the same items effectively so that the size of database cannot be reduced sufficiently. The overall performance of algorithms is degraded consequently. Thus an algorithm HUITWU is proposed in this paper for mining HUIs. A novel data structure HUITwu-Tree is adopted to efficiently calculate the utilities of itemsets in a database. Extensive studies with both sparse and dense datasets have demonstrated that our proposed algorithm is more than an order of magnitude faster and consumes less memory than the state-of-the-art algorithms.

关键词： data mining high-utility itemset pattern growth

Tensile force correction calculation method for prestressed construction of tension structures

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1201-1207页

作者： Xin ZHUO guo-fa ZHANG Koichiro IshiKAWA Dao-an LOU Department of Civtl Engmeermg Zhejiang University Hangzhou 310027 China Department of Architecture and Civil Engineering Fukui University Fukui 910-8507 Japan Zhejiang Zhancheng Construction Group Co. Ltd. Hangzhou 310005 China

factors such as errors during the fabrication or construction of structural components and errors of calculation as- sumption or calculation methods, are very likely to cause serious deviation of many strings’ actual prestressing forces from the designed values during tension structure construction or service period, and further to threaten the safety and reliability of the structure. Aiming at relatively large errors of the prestressing force of strings in a tension structure construction or service period, this paper proposes a new finite element method (FEM), the "tensile force correction calculation method". Based on the measured prestressing forces of the strings, this new method applies the structure from the zero prestressing force status approach to the measured prestressing force status for the first phase, and from the measured prestressing force status approach to the designed prestressing force status for the second phase. The construction tensile force correction value for each string can be obtained by multi-iteration with FEM. Using the results of calculation, the strings’ tensile force correction by group and in batch will be methodic, simple and accurate. This new calculation method can be applied to the prestressed correction construction simulation analysis for tension structures.

关键词： Tension structures Prestressed construction High precision

Inflammation in diabetic retinopathy: possible roles in pathogenesis and potential implications for therapy

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Neural Regeneration Research 2023年第5期18卷 976-982页

作者： Lei Tang guo-Tong Xu Jing-fa Zhang Department of Ophthalmology of Tongji Hospital Tongji Eye InstituteDepartment of Regenerative Medicineand Department of PharmacologyTongji University School of MedicineShanghaiChina Department of Ophthalmology Shanghai General Hospital(Shanghai First People’s Hospital)Shanghai Jiao Tong UniversityShanghaiChina National Clinical Research Center for Eye Diseases Shanghai Key Laboratory of Ocular Fundus DiseasesShanghai Engineering Center for Visual Science and PhotomedicineShanghai Engineering Center for Precise Diagnosis and Treatment of Eye DiseasesShanghaiChina

Diabetic retinopathy, characterized as a microangiopathy and neurodegenerative disease, is the leading cause of visual impairment in diabetic patients. Many clinical features observed in diabetic retinopathy, such as capillary occlusion, acellular capillaries and retinal non-perfusion, aggregate retinal ischemia and represent relatively late events in diabetic retinopathy. In fact, retinal microvascular injury is an early event in diabetic retinopathy involving multiple biochemical alterations, and is manifested by changes to the retinal neurovascular unit and its cellular components. Currently, intravitreal anti-vascular endothelial growth factor therapy is the firstline treatment for diabetic macular edema, and benefits the patient by decreasing the edema and improving visual acuity. However, a significant proportion of patients respond poorly to anti-vascular endothelial growth factor treatments, indicating that factors other than vascular endothelial growth factor are involved in the pathogenesis of diabetic macular edema. Accumulating evidence confirms that low-grade inflammation plays a critical role in the pathogenesis and development of diabetic retinopathy as multiple inflammatory factors, such as interleukin-1β, monocyte chemotactic protein-1 and tumor necrosis factor-α, are increased in the vitreous and retina of diabetic retinopathy patients. These inflammatory factors, together with growth factors such as vascular endothelial growth factor, contribute to blood-retinal barrier breakdown, vascular damage and neuroinflammation, as well as pathological angiogenesis in diabetic retinopathy, complicated by diabetic macular edema and proliferative diabetic retinopathy. In addition, retinal cell types including microglia, Müller glia, astrocytes, retinal pigment epithelial cells, and others are activated, to secrete inflammatory mediators, aggravating cell apoptosis and subsequent vascular leakage. New therapies, targeting these inflammatory molecules or relate

关键词： anti-inflammation therapy anti-vascular endothelial growth factor diabetic retinopathy hyperreflectivity foci inflammation inflammatory cells inflammatory cytokines leukostasis microglia Müller cells

Gamma-glutamyl transferase 5 overexpression in cerebrovascular endothelial cells improves brain pathology,cognition,and behavior in APP/PS1 mice

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Neural Regeneration Research 2025年第2期20卷 533-547页

作者： Yanli Zhang Tian Li Jie Miao Zhina Zhang Mingxuan Yang Zhuoran Wang Bo Yang Jiawei Zhang Haiting Li Qiang Su Junhong guo Department of Neurology First Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Neurology Sixth Hospital of Shanxi Medical University(General Hospital of Tisco)TaiyuanShanxi ProvinceChina Department of Physiology Key Laboratory of Cellular PhysiologyMinistry of EducationShanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Hernia and Abdominal Wall Surgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Laboratory Medicine of Fenyang College Shanxi Medical UniversityFenyangShanxi ProvinceChina

In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial ***,the functional role of GGT5 in the development of Alzheimer’s disease remains *** study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer’s disease,as well as the underlying *** observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer’s disease(Aβ_(1-42)-treated hCMEC/D3 and bEnd.3 cells),as well as in the APP/PS1 mouse ***,injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive ***,increasing GGT5 expression in cerebrovascular endothelial cells reduced levels of both soluble and insoluble amyloid-βin the brains of APP/PS1 *** effect may be attributable to inhibition of the expression ofβ-site APP cleaving enzyme 1,which is mediated by nuclear factor-kappa *** findings demonstrate that GGT5 expression in cerebrovascular endothelial cells is inversely associated with Alzheimer’s disease pathogenesis,and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 *** findings suggest that GGT5 expression in cerebrovascular endothelial cells is a potential therapeutic target and biomarker for Alzheimer’s disease.

关键词： Alzheimer’s disease amyloid-β APP/PS1 mice cerebrovascular endothelial cells cognitive deficits gamma-glutamyl transferase 5 neurovascular unit nuclear factor‐kappa B synaptic plasticity β-site APP cleaving enzyme 1

Micro/atomic-scale vibration induced superlubricity

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Friction 2021年第5期9卷 1163-1174页

作者： Shuai shi Dan guo Jianbin LUO State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China China Fortune Land Development Industrial Investment Co. Ltd.Beijing 100027China

With the rapid development of industry,the inconsistency between the rapid increase in energy consumption and the shortage of resources is becoming *** is one of the main causes of energy consumption;thus,the emergence of superlubricity technology can substantially improve the energy efficiency in motion *** this study,an efficient method to control superlubricity at the atomic‐scale is *** method employs vibrational excitation,which is called vibration induced superlubricity(VIS).The VIS can be easily and steadily achieved by employing external vibration in three *** simple method does not depend on the type of sample and *** of oscillation amplitude,frequency,scanning speed,and normal force(F_(N))on friction were *** and simulated explorations verified the practical approach for reducing energy dissipation and achieving superlubricity at the atomic‐scale.

关键词： superlubricity atomic‐scale vibration energy dissipation

Improved lateral-dynamics-intended railway vehicle model involving nonlinear wheel/rail interaction and car body flexibility

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Acta Mechanica Sinica 2021年第6期37卷 997-1012,I0003页

作者： Huailong shi Ren Luo Jinying guo State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu610031China School of Automobile and Transportation Chengdu Technological UniversityChengdu611730China

To study the vehicle hunting behavior and its coupling with car body vibrations,a simplified lateral-dynamics-intended railway vehicle model is developed.A two-truck vehicle is modeled as a 17 degrees-of-freedom rigid system,into which the car body flexural vibrations of torsion and bending modes are further *** wheel/rail interaction employs a real-time calculation for the Hertzian normal contact,in which the nonlinear curvatures of wheel and rail profiles are presented as functions of wheelset lateral movement and/or yaw *** the tangential/creep forces are analytically expressed as the Hertzian contact patch geometry,and lead to a continuous and fast calculation compared to a look-up table *** is shown that the hunting frequencies of the vehicle model and a truck model differ significantly,which verifies the necessity of the whole vehicle *** the case of low wheel/rail conicity,the hunting frequency increases linearly with vehicle speed,whereas it rises slowly at high speed for a large *** of hunting frequency and damping ratio between various conicities shows that first hunting(car body hunting)may occur when the vehicle is operated at a low speed in a small conicity case,while a second hunting(truck hunting)appears when the vehicle is operated at a high speed in a large conicity *** analysis of linear and nonlinear vehicle models was carried out through coast down method and constant speed *** tell that the linear one overestimates the lateral *** the structural vibrations of car body can be ignored in the stability *** to existing simplified models for hunting stability study,the proposed simplified vehicle model released limitations in the nonlinear geometries of wheel/rail profiles,and it is suitable for a frequency-domain analysis by deriving the analytical expressions of the normal and tangential wheel/rail contact forces.

关键词： Railroad vehicle Wheel/rail contact Analytical forms Hunting stability Car body flexibility

Enhancive effect of N,N'-dinitrosopiperazine on inducing precancerous lesion on nasal and/or nasopharyngeal epithelia of TgN(p53mt-LMP1)/HT mice

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第3期10卷 172-179页

作者： Dao-fa TIAN Ying-chun HE fang-guo LU fa-qing TANG faculty of Integrative Medicine Changsha 410007 China) faculty cf Basic Medicine Chinese Medicine University of Hunan Changsha 410007 China Department of Clinical Laboratory the First Xiangya Hospital Central South University Changsha 410008 China

Objective： To investigate the enhancive effect ofN, N′-dinitrosopiperazine （DNP） on induced carcinogenesis in nasal and/or nasopharyngeal epithelia among TgN（p53mt-LMP1）/HT transgenic mice to examine the underlying mechanism for the development of nasopharyngeal carcinoma （NPC）. Methods： TgN（p53mt-LMP1）/HT transgenic mice and the same strain of C57BL/6J wild-type mice both at the age of 5 months were randomly divided into 2 groups in parallel, respectively, i.e., TgN（p53mt-LMP1）/HT cancerous lesion-inducing group （T1）, TgN（p53mt-LMP1）/HT control group （TC）, C57BL/6J cancerous lesion-inducing group （CI）, and C57BL/6J control group （CC）. TI and CI mice were treated only with DNP for 16 weeks, twice each week, while TC and CC mice were given the same volume of saline as *** the end of treatment, animals were sacrificed to collect epithelial tissue samples from nasal cavity and nasopharynx for pathohistological evaluation by hacmatoxylin and eosin （HE） staining and for determination on the expression ofTRAF2, c-Jun, and p 16 by immunohistochemistry. Results： Atypical hyperplasia was more significant in the samples of TI than in those of TC, CI, and CC, with the rates of lesions being 90%, 10%, 0, and 0 （P〈0.01） respectively, though DNP was used alone in a much shortened inducing period at less dosage and without the use of carcinogenic promoter 12-0-tetradecanoylphorbol-13-acetate as usual. The expressions of tumor necrosis factor （TNF） receptor-associated factor 2 （TRAF2） and c-Jun in these samples were significantly up-regulated in TI （P〈0.0 I）, while tbe expression of p16 was significantly lower in TI than in the other groups （P〈0.01）. Conclusion： TgN（p53mt-LMPI）/HT mice hold inherited constitutional defect in immune surveillance function, which can be aggravated by environmental carcinogens, such as DNP used even though in a much less strength. The enhanced carcinogenesis-inducing effect of DNP on TgN（p53mt-LMP1）/HT mice should be closely associated with abn

关键词： Nasal epithelia Nasopharyngeal epithelia Precancerous lesions N N′-dinitrosopiperazine (DNP) Activator protein-1(AP- 1) pathway Signal transduction

Influence of Thermally Treated Flue Gas Desulfurization(FGD) Gypsum on Performance of the Slag Powder Concrete

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Journal of Wuhan University of Technology(Materials Science) 2013年第6期28卷 1122-1127页

作者： guo Xiaolu shi Huisheng Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education Tongji University Environmental Materials Institute

The feasibility of flue gas desulphurization （FGD） as concrete admixture was studied. A combined concrete admixture of the thermally-treated FGD gypsum and slag powder was explored. The FGD gypsum was roasted at 200℃ for 60 min and then mixed with the slag powder to form FGD gypsum-slag powder combined admixture in which the SO3 content was 3.5wt%. Cement was partially and equivalently replaced by slag powder alone or FGD gypsum-slag powder, at concentration of 25wt%, 40wt%, and 50wt%, respectively. The setting times, hydration products, total porosity and pore size distributions of the paste were determined. The compressive strength and drying shrinkage of cement mortar and concrete were also tested. The experimental results show that, in the presence of FGD gypsum, the setting times are much slower than those of pastes in the absence of FGD gypsum. The combination of FGD gypsum and slag powder provides synergistic benefits above that of slag powder alone. The addition of FGD gypsum provides benefit by promoting ettringite formation and forms a compact microstructure, increasing the compressive strength and reduces the drying shrinkage of cement mortar and concrete.

关键词： flue gas desulfurization (FGD) gypsum slag powder compressive strength drying shrinkage mortar concrete

Growth and Spectral Properties of Nd^(3+) Doped KLa(MoO_4)_2 Crystal

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Chinese Journal of Structural Chemistry 2006年第2期25卷 192-196页

作者： WANG guo-Jian HAN Xiu-Mei LONG Xi-fa WANG guo-Fu Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Nd^3＋ doped KLa（MoO4）2 single crystal with the size up to Ф25 × 40 mm^3 was grown by the Czochralski technique. The absorption and luminescence spectra of trivalent neodymium in KLa（MoO4）2 crystal were investigated at room temperature. The absorption and emission cross 10-20 sections are 3.02 ×10^-20 cm^2 at 808 nm and 20.01 × 10^-2 cm^2 at 1061 nm, respectively. The fluorescence lifetime is 164μs at room temperature.

关键词： Nd^3+ :KLa(MoO4)2 crystal crystal growth spectral properties