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Differentially private SGD with random features

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 1-23页

作者： WANG Yi-guang GUO zheng-chu Polytechnic Institute of Zhejiang University Zhejiang UniversityHangzhou 310015China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China

In the realm of large-scale machine learning,it is crucial to explore methods for reducing computational complexity and memory demands while maintaining generalization performance.Additionally,since the collected data may contain some sensitive information,it is also of great significance to study privacy-preserving machine learning algorithms.This paper focuses on the performance of the differentially private stochastic gradient descent(SGD)algorithm based on random features.To begin,the algorithm maps the original data into a lowdimensional space,thereby avoiding the traditional kernel method for large-scale data storage requirement.Subsequently,the algorithm iteratively optimizes parameters using the stochastic gradient descent approach.Lastly,the output perturbation mechanism is employed to introduce random noise,ensuring algorithmic privacy.We prove that the proposed algorithm satisfies the differential privacy while achieving fast convergence rates under some mild conditions.

关键词： learning theory differential privacy stochastic gradient descent random features reproducing kernel Hilbert spaces

Structural characterization of three acidic polysaccharides from Opuntia dillenii Haw.fruits and their protective effect against hydrogen peroxide-induced oxidative stress in Huh-7 cells

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Food Science and Human Wellness 2024年第4期13卷 1929-1942页

作者： Rui Liu Fangxin chu zheng Yan Hanqing Chen School of Food and Biological Engineering Hefei University of TechnologyHefei 230601China Engineering Research Center of Bio-Process Ministry of EducationHefei University of TechnologyHefei 230601China

Three novel acidic polysaccharide fractions(OFPP-1,OFPP-2,OFPP-3)with different m olecular weights(803.7,555.1 and 414.5 k Da)were isolated from the peeled Opuntia dillenii Haw.fruits by alkali-extraction,graded alcohol precipitation and column chromatography.Structural analysis indicated that OFPPs were pectic polysaccharides consisting of rhamnose,arabinose and galactose residues.The backbone of OFPP-1 consisted of a repeating unit→6-α-D-Galp A-(1→2)-α-L-Rhap-(1→with T-α-D-Galp A-(1→6)-α-D-Galp A-(1→4)-α-D-Glcp-(1→,T-β-D-Xylp-(1→6)-α-D-Galp A-(1→4)-α-D-Glcp-(1→or T-α-D-Galp A-(1→3)-α-L-Araf-(1→as the side chains.The backbone of OFPP-2 consisted of a disaccharide repeating unit→2)-α-L-Rhap-(1→4)-β-D-Galp A-(1→with T-β-L-Araf-(1→as the branches substituted at the O-4 position of→2,4)-α-LRhap-(1→.Whereas the backbone of OFPP-3 was→2,4)-α-L-Rhap-(1→2)-α-L-Rhap-(1→3)-β-L-Araf-(1→or→2,4)-α-L-Rhap-(1→2)-α-L-Rhap-(1→4)-β-D-Galp A-(1→,which was branched at the O-4 position of→2,4)-α-L-Rhap-(1→.Moreover,these three polysaccharide fractions could protect Huh-7 cells against H2O2-induced oxidative stress to different extents by decreasing the MDA content and increasing the SOD,CAT,GSH-Px activities and the GSH level in the Huh-7 cells.These results suggest that OFPPs have the potential to be used as natural antioxidants.

关键词： Opuntia dillenii Haw.fruits Polysaccharide Alkali extraction Structural characterization Oxidative stress

TGF-βsignaling in health,disease,and therapeutics

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1466-1505页

作者： Ziqin Deng Tao Fan chu Xiao He Tian Yujia zheng chunxiang Li Jie He Department of Thoracic Surgery National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

ransforming growth factor(TGF)-βis a multifunctional cytokine expressed by almost every tissue and cell type.The signal transduction of TGF-βcan stimulate diverse cellular responses and is particularly critical to embryonic development,wound healing,tissue homeostasis,and immune homeostasis in health.The dysfunction of TGF-βcan play key roles in many diseases,and numerous targeted therapies have been developed to rectify its pathogenic activity.In the past decades,a large number of studies on TGF-βsignaling have been carried out,covering a broad spectrum of topics in health,disease,and therapeutics.Thus,a comprehensive overview of TGF-βsignaling is required for a general picture of the studies in this field.In this review,we retrace the research history of TGF-βand introduce the molecular mechanisms regarding its biosynthesis,activation,and signal transduction.We also provide deep insights into the functions of TGF-βsignaling in physiological conditions as well as in pathological processes.TGF-β-targeting therapies which have brought fresh hope to the treatment of relevant diseases are highlighted.Through the summary of previous knowledge and recent updates,this review aims to provide a systematic understanding of TGF-βsignaling and to attract more attention and interest to this research area.

关键词： homeostasis healing wound

DLF-YOLOF:an improved YOLOF-based surface defect detection for steel plate

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Journal of Iron and Steel Research(International) 2024年第2期31卷 442-451页

作者： Guang-hu Liu Mao-xiang chu Rong-fen Gong Ze-hao zheng School of Electronic and Information Engineering University of Science and Technology LiaoningAnshan114051LiaoningChina

Surface defects can affect the quality of steel plate.Many methods based on computer vision are currently applied to surface defect detection of steel plate.However,their real-time performance and object detection of small defect are still unsatisfactory.An improved object detection network based on You Only Look One-level Feature(YOLOF)is proposed to show excellent performance in surface defect detection of steel plate,called DLF-YOLOF.First,the anchor-free detector is used to reduce the network hyperparameters.Secondly,deformable convolution network and local spatial attention module are introduced into the feature extraction network to increase the contextual information in the feature maps.Also,the soft non-maximum suppression is used to improve detection accuracy significantly.Finally,data augmentation is performed for small defect objects during training to improve detection accuracy.Experiments show the average precision and average precision for small objects are 42.7%and 33.5%at a detection speed of 62 frames per second on a single GPU,respectively.This shows that DLF-YOLOF has excellent performance to meet the needs of industrial real-time detection.

关键词： Steel surface defects detection YOLOF Anchor-free detector Small object detection Real-time detection

New perspectives in free nitrous acid (FNA) uses for sustainable wastewater management

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 161-168页

作者： Zhiqiang Zuo min zheng Tao Liu Yongzhen Peng Zhiguo Yuan National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology Engineering Research Center of BeijingBeijing University of TechnologyBeijing 100124China Australian Centre for Water and Environmental Biotechnology The University of QueenslandSt.LuciaQLD 4072Australia Water Research Centre School of Civil and Environmental EngineeringUniversity of New South WalesSydneyNew South Wales 2052Australia Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077China School of Energy and Environment City University of Hong KongHong Kong 999077China

The biocidal effects of free nitrous acid (FNA) have found applications in multiple units in an urban wastewater system, including sewer networks, wastewater treatment processes, and sludge treatment processes. However, these applications are associated with chemical costs as both nitrite and acid are needed to produce FNA at the required levels. The recent discovery of novel acid-tolerant ammonia oxidizers offers the possibility to produce FNA from domestic wastewater, enabling the development of next-generation FNA-based technologies capable of achieving self-sustaining FNA production. In this study, we focus on the concept of in situ FNA generation facilitated by acid-tolerant ammonia oxidizers and highlight the multiple benefits it creates, after a brief review of the historical development of FNA-based technologies. We will discuss how wastewater systems can be made more energy-efficient and sustainable by leveraging the potential of acid-tolerant ammonia oxidizers.

关键词： Free nitrous acid Acid-toler antammonia oxidizer In situ generationl Wastewater management

Molecular regulation of the key specialized metabolism pathways in medicinal plants

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Journal of Integrative Plant Biology 2024年第3期66卷 510-531页

作者： min Shi Siwei Zhang Zizhen zheng Itay Maoz Lei Zhang Guoyin Kai Zhejiang Provincial International S&T Cooperation Base for Active Ingredients of Medicinal and Edible Plants and Health Zhejiang Provincial Key TCM Laboratory for Chinese Resource Innovation and TransformationSchool of Pharmaceutical SciencesJinhua AcademyZhejiang Chinese Medical UniversityHangzhou 310053China Department of Postharvest Science Agricultural Research OrganizationVolcani CenterRishonLeZion 7505101Israel Department of Pharmaceutical Botany School of PharmacyNaval Medical UniversityShanghai 200433China

The basis of modern pharmacology is the human ability to exploit the production of specialized metabolites from medical plants,for example,terpenoids,alkaloids,and phenolic acids.However,in most cases,the availability of these valuable compounds is limited by cellular or organelle barriers or spatio-temporal accumulation patterns within different plant tissues.Transcription factors(TFs)regulate biosynthesis of these specialized metabolites by tightly controlling the expression of biosynthetic genes.Cutting-edge technologies and/or combining multiple strategies and approaches have been applied to elucidate the role of TFs.In this review,we focus on recent progress in the transcription regulation mechanism of representative high-value products and describe the transcriptional regulatory network,and future perspectives are discussed,which will help develop high-yield plant resources.

关键词： biosynthesis medicinal plants omics secondary metabolism transcription factors

π-conjugated chromophore functionalized high-nuclearity titanium-oxo clusters containing structural unit of anatase for photocatalytic selective oxidation of sulfides

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Rare Metals 2024年第4期43卷 1736-1746页

作者： Ling-Rong Liao Dong-chun zheng Pin-Xi Ou Qi-Xin Zhao Wei-min Xuan Qi zheng State Key Laboratory for Modification of Chemical Fibers and Polymer Materials & College of Materials Science and Engineering Donghua University State Key Laboratory for Modification of Chemical Fibers and Polymer Materials and College of Chemistry and Chemical Engineering Donghua University

N-doping has significant influence in manipulating the properties of TiO2,and this has stimulated the development of N-donor-functionalized titanium-oxo clusters（TOCs） as molecular models to study the structure-property relationship.However,the structural type and photoresponsive application are still limited for such TOCs,especially regarding the high-nuclearity TOCs that contain structure unit of TiO2for photocatalysis.Herein,we showed the synthesis of a series of high-nuclearity TOCs 1-3 compounds using π-conjugated 1,10-phenanthroline（phen） as chromophore and N-donor functional ligand.Compound 1 features cocrystal structure composed of one [Ti26]2+and half [Ti22]2+,which renders it as the first cocrystallized TOC containing two positively charged species and phen-functionalized TOC showing the highest nuclearity up to 37 Ti centers.By adjusting the synthetic conditions,the individual {Ti22} and {Ti26} clusters can also be isolated as Compounds 2 and 3,respectively.The core structure of {Ti22} is mainly constructed from four lacunary {Ti4} derived from pentagonal {Ti（Ti）5} unit,while {Ti26} is built from four complete {Ti（Ti）5} unit.Notably,a {Ti8O14} structure unit of anatase TiO2can be identified in {Ti26}.Based on the unique structural features and proper photophysical and photochemical properties of Compounds 1-3,they are applied for photocatalytic sulfoxidation.Owing to the presence of anatase structure unit in {Ti26} and the synergistic effect from {Ti22} and {Ti26},the catalytic performance presents in the order of Compound 1> Compound 3> Compound 2.This work provides excellent models to understand the structureproperty relationship from the perspective of cocrystallization and Ti-O binding model and will further promote the application of TOCs as functional catalysts for organic transformation.

关键词： Titanium-oxo cluster Molecular model of anatase TiO 2 High nuclearity π-conjugated chromophore Photocatalytic sulfoxidation

Effect of titanium on the sticking of pellets based on hydrogen metallurgy shaft furnace:Behavior analysis and mechanism evolution

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International Journal of minerals,Metallurgy and Materials 2024年第2期31卷 282-291页

作者： Jinge Feng Jue Tang Zichuan Zhao Mansheng chu Aijun zheng Xiaobing Li Xiao’ai Wang School of Metallurgy Northeastern UniversityShenyang 110819China Institute for Frontier Technologies of Low-carbon Steelmaking Northeastern UniversityShenyang 110819China Liaoning Low-carbon Steelmaking Technology Engineering Research Center Northeastern UniversityShenyang 110819China Engineering Research Center of Frontier Technologies for Low-carbon Steelmaking(ministry of Education Shenyang 110819China Zhang Xuan Technology of HBIS Group Co. Ltd.Shijiazhuang 050000China Xuanhua Iron and Steel Group Co. Ltd.Shijiazhuang 050000China Iron and Steel Research Institute of HBIS Group Co. Ltd.Shijiazhuang 050000China

Direct reduction based on hydrogen metallurgical gas-based shaft furnace is a promising technology for the efficient and low-carbon smelting of vanadium-titanium magnetite.However,in this process,the sticking of pellets occurs due to the aggregation of metal-lic iron between the contact surfaces of adjacent pellets and has a serious negative effect on the continuous operation.This paper presents a detailed experimental study of the effect of TiO2 on the sticking behavior of pellets during direct reduction under different conditions.Results showed that the sticking index(SI)decreased linearly with the increasing TiO2 addition.This phenomenon can be attributed to the increase in unreduced FeTiO3 during reduction,leading to a decrease in the number and strength of metallic iron interconnections at the sticking interface.When the TiO2 addition amount was raised from 0 to 15wt%at 1100°C,the SI also increased from 0.71%to 59.91%.The connection of the slag phase could be attributed to the sticking at a low reduction temperature,corresponding to the low sticking strength.Moreover,the interconnection of metallic iron became the dominant factor,and the SI increased sharply with the increase in re-duction temperature.TiO2 had a greater effect on SI at a high reduction temperature than at a low reduction temperature.

关键词： titanium sticking index hydrogen metallurgy direct reduction pellets

A simple and successful treatment for rupture and defect of the posterior third superior sagittal sinus caused by open depressed skull fracture:A case report

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Chinese Journal of Traumatology 2022年第2期25卷 115-117页

作者： Geng-Huan Wang He-Ping Shen zheng-min chu Jian-Guo Shen Jian Shen Department of Neurosurgery The Second Affiliated Hospital of Jiaxing UniversityJiaxing314000Zhejiang ProvinceChina

It is extremely dangerous to treat the posterior third of the superior sagittal sinus (PTSSS) surgically, since it is usually not completely ligated. In this report, the authors described the case of a 27-year-old man with a ruptured and defective PTSSS caused by an open depressed skull fracture, which was treated by ligation of the PTSSS and the patient achieved a positive recovery. The patient's occiput was hit by a height-limiting rod and was in a mild coma. A CT scan showed an open depressed skull fracture overlying the PTSSS and a diffuse brain swelling. He underwent emergency surgery. When the skull fragments were removed, a 4 cm segment of the superior sagittal sinus (SSS) and the adjacent dura mater were removed together with bone fragments. Haemorrhage occurred and blood pressure dropped. We completed the operation by ligating the severed ends of the fractured sagittal sinus. One month after the operation, apart from visual field defects, he recovered well. In our opinion, in primary hospitals, when patients with severely injured PTSSS cannot sustain a long-time and complicated operation, e.g., the bypass using venous graft, and face life-threatening conditions, ligation of the PTSSS is another option, which may unexpectedly achieve good results.

关键词： Depressed skull fracture Superior sagittal sinus Ligation Prognoses