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Reproductive toxicity and underlying mechanisms of di(2-ethylhexyl) phthalate in nematode Caenorhabditis elegans

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Journal of Environmental Sciences 2021年第7期33卷 1-10页

作者： Jingjing Li Man Qu Mei Wang Ying Yue Zhaofang Chen ran Liu Yuanqing Bu yunhui Li Key Laboratory of Environmental Medicine Engineering Ministry of EducationSchool of Public HealthSoutheast UniversityNanjing 210009China State Key Laboratory of Pollution Control&Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023China Nanjing Institute of Environmental Science Key Laboratory of Pesticide Environmental Assessment and Pollution ControlMinistry of Ecology and EnvironmentNanjing 210042China

DEHP(di(2-ethylhexyl) phthalate) is an endocrine disruptor commonly found in plastic products that has been associated with reproduction alterations, but the effect of DEHP on toxicity is still widely unknown. Using DEHP concentrations of 10, 1, and 0.1 mg/L, we showed that DEHP reduced the reproductive capacity of Caenorhabditis elegans after 72 hr. of exposure. DEHP exposure reduced the reproductive capacity in terms of decreased brood sizes, egg hatchability(0.1, 1 and 10 mg/L), and egg-laying rate(1 and 10 mg/L), and increased numbers of fertilized eggs in the uterus(1 and 10 mg/L). DEHP also caused damage to gonad development. DEHP decreased the total number of germline cells, and decreased the relative area of the gonad arm of all exposure groups, with worms in the 1 mg/L DEHP exposure group having the minimum gonad arm area. Additionally, DEHP caused a significant concentration-dependent increase in the expression of unc-86. Autophagy and ROS contributed to the enhancement of DEHP toxicity in reducing reproductive capacity, and glutathione peroxidase and superoxide dismutase were activated as the antioxidant defense in this study. Hence, we found that DEHP has a dual effect on nematodes. Higher concentration(10 mg/L) DEHP can inhibit the expression of autophagy genes( atg-18, atg-7, bec-1, lgg-1 and unc-51), and lower concentrations(0.1 and 1 mg/L) can promote the expression of autophagy genes. Our data highlight the potential environmental risk of DEHP in inducing reproductive toxicity toward the gonad development and reproductive capacity of environmental organisms.

关键词： DEHP Brood sizes Autophagy Reactive oxygen species Superoxide dismutase Glutathione peroxidase

Probing Structural Evolution of High-capacity Layered Oxide Cathode

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Chinese Journal of Structural Chemistry 2022年第10期41卷 2-3页

作者： yunhui Huang School of Materials Science and Engineering Huazhong University of Science and TechnologyWuhan 330074China

In transitional metal (TM) layered oxide cathode materials, the energy storage relies on Li-ion intercalation/de-intercalation in the Li layers. To achieve higher energy density, lithium- and manganese-rich (LMR) layered oxides are developed by enabling Listorage in TM layers. Nevertheless, this process involves structural evolution (e.g., oxygen release) of cathode materials that might eventually lead to performance degradation.

关键词： eventually intercalation manganese

Clustering algorithm based on density function and nichePSO

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Journal of Systems Engineering and Electronics 2012年第3期23卷 445-452页

作者： Chonghui Guo yunhui Zang Institute of Systems Engineering Dalian University of TechnologyDalian 116024E R.China

This paper introduces niching particle swarm optimiza- tion （nichePSO） into clustering analysis and puts forward a cluster- ing algorithm which uses nichePSO to optimize density functions. Firstly, this paper improves main swarm training models and in- creases their ability of space searching. Secondly, the radius of sub-swarms is defined adaptively according to the actual clus- tering problem, which can be useful for the niches＇ forming and searching. At last, a novel method that distributes samples to the corresponding cluster is proposed. Numerical results illustrate that this algorithm based on the density function and nichePSO could cluster unbalanced density datasets into the correct clusters auto- matically and accurately.

关键词： niching particle swarm optimization (nichePSO) density-based clustering automatic clustering.

Direct silylation reactions of inert C-H bonds via transition metal catalysis

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Science China Chemistry 2015年第8期58卷 1266-1279页

作者： yunhui Yang Congyang Wang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences

In the past thirty years,transition metal catalyzed silylation of inert C–H bonds has attracted intensive attention due to the importance and wide use of organosilicon *** this review,the silylation reactions of inert C–H bonds catalyzed by transition metal complexes of Ir,Rh,Ru,Pt,Pd,Ni,and Sc,and the strategies utilized to access the site-selective C–H silylation products have been ***,the mechanisms of C–H silylation reactions have been discussed briefly.

关键词： transition metal inert C-H bond catalysis silylation regioselectivity

Image-Based 3D Pose Reconstruction of Surgical Needle for Robot-Assisted Laparoscopic Suturing

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Chinese Journal of Electronics 2018年第3期27卷 476-482页

作者： ZHONG Fangxun LIU yunhui CUHK T Stone Robotics Institute The Chinese University of Hong Kong

We present a new method to solve the recognition and localisation problem of a surgical needle for robot-assisted laparoscopy. Based on the observation from a single monocular laparoscopic image, we propose a new modelling method to parametrise the full 3 D pose of the surgical needle by constrained Degrees of freedom(DOFs) using only two generalised variables. To obtain effective image feedback for the modelling, a feature segmentation algorithm is introduced from probabilistic linear constraints in RGB colour space, constructed from typical laparoscopic images. An iterative algorithm using gradient descent rule is implemented to converge the computed needle's pose to its real one. Experiments demonstrate the feasibility of the proposed scheme using laparoscopic torso models.

关键词： Suturing needle Pose reconstruction Robot-assisted laparoscopy Image segmentation

Strategic Response to a Powerful Downstream Retailer:Difference-Setting Wholesale Pricing Contract and Partial Forward Integration

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Journal of Systems Science and Systems Engineering 2022年第1期31卷 89-110页

作者： Conglin Hu Bin Liu yunhui Liu School of Economics and Management Shanghai Maritime UniversityShanghaiChina201306 Research Center for Contemporary Management Key Research Institute of Humanities and Social Sciences at UniversitiesSchool of Economics and ManagementTsinghua UniversityBeijing100084China

We study a supply chain consisted of a supplier and both retailers,and the supplier sells a single product through a dominant retailer and a weak *** aggressive bargaining behavior of the dominant retailer brings the supplier much concern and two feasible strategies are presented to respond to that:difference-setting wholesale pricing contract and integration with the weak *** investigate the decisions of supply chain members under each solution and find that,compared to the traditional form,the supplier always benefits from announcing the difference-setting wholesale pricing contract for it not only raises the marginal wholesale profits of both channels but also reduces the market share of the dominant retailer,thus potentially weakening its channel *** addition,we show that combining with the weak retailer is not a wise choice for suppliers when the dominant retailer with relatively little bargaining power enjoys a large market ***,by comparing the equilibria of these two solutions,we find that the optimal choice for suppliers depends not only on the difference in market share but also on the dominant retailer's bargaining power in the negotiation.

关键词： Channel power bargaining wholesale-price contract forward integration

Forging Three Single Bonds on One Carbon via Metal Carbynes or Carbyne Equivalents

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Chinese Journal of Chemistry 2021年第12期39卷 3481-3484页

作者： yunhui Yang Congyang Wang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Metal carbyne(M≡C)complexes have been discovered for nearly half a century,however,they gained far less study in comparison with metal-carbon single bond(M—C)and metal carbene(M=C)species in synthetic *** to three sigma bonds are possibly forged on a single carbon through metal carbynes or carbyne equivalents,which holds great potentials in organic synthesis but also requires high efficiency of bond formation and precise control of reactivity and *** this line,two systems based on stoi-chiometric transformations of manganese carbynes and ruthenium/rhodium-catalyzed reactions of diazo hypervalent iodine reagents,carbyne equivalents,have emerged recently,which will be highlighted *** potentials and challenges in this intriguing area are also briefly discussed.

关键词： Transition metals Carbyne ligands Manganese Three sigma bonds Stoichiometric/Catalytic reactions

Multi-camera calibration method based on minimizing the difference of reprojection error vectors

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Journal of Systems Engineering and Electronics 2018年第4期29卷 844-853页

作者： HUO Ju LI yunhui YANG Ming School of Electrical Engineering Harbin Institute of Technology Control and Simulation Center Harbin Institute of Technology

In order to achieve a high precision in three-dimensional（3D） multi-camera measurement system, an efficient multi-cameracalibration method is proposed. A stitching method of large scalecalibration targets is deduced, and a fundamental of multi-cameracalibration based on the large scale calibration target is *** avoid the shortcomings of the method, the vector differencesof reprojection error with the presence of the constraint conditionof the constant rigid body transformation is modelled, and mini-mized by the Levenberg-Marquardt （LM） method. Results of thesimulation and observation data calibration experiment show thatthe accuracy of the system calibrated by the proposed methodreaches 2 mm when measuring distance section of 20 000 mmand scale section of 7 000 mm × 7 000 mm. Consequently, theproposed method of multi-camera calibration performs better thanthe fundamental in stability. This technique offers a more uniformerror distribution for measuring large scale space.

关键词： vision measurement multi-camera calibration field stitching vector error

Excellent plasma electrolytic oxidation coating on AZ61 magnesium alloy under ordinal discharge mode

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Journal of Magnesium and Alloys 2022年第9期10卷 2460-2474页

作者： Weiyi Zhang yunhui Du Peng Zhang School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

In the preparation of plasma electrolytic oxidation(PEO)coating,the rapid heating of freely-happened electron avalanche under traditional discharge(TD)mode inevitably results in a strong eruption of electric breakdown *** PEO coating is loose and invariably composed of a very thin inner dense layer and an outer loose layer,as a result of which its properties and application have been limited *** this work,for purpose of weakening the eruption of breakdown melt,thickening the inner dense layer,densifying the outer loose layer and improving the performance of PEO coating,ordinal discharge(OD)mode of PEO coating is developed by regulating the mass ratio of MgF_(2) to MgO(α)and voltage in the PEO investigation on AZ61 magnesium alloy in KF-KOH *** formation mechanism under different discharge mode,electrochemical corrosion and wear of PEO coatings are *** results show that the suitableαand voltage for effective OD are 1.3 and 130 V under which the freely-happened electron avalanche in MgF_(2) under TD mode can be restricted by the adequate adjacent *** with TD mode,the inner dense layer,in which the(10¯1)plane of MgF_(2) is parallel to the(111)plane of MgO at their well-knit semi-coherent interface,is thickened to 2.4∼7.2 times,the corrosion potential(E_(corr))improvement is enlarged to 3.6∼13.2 times and the corrosion current intensity(I_(corr))is reduced from 10.8∼9.499 to 0.433(10^(−6) A/cm^(2)).The outer loose layer is densified and the wear rate is lessened 65.5%∼89.8%by the evident melioration in surface porosity,impedance and *** work deepens the understanding about the discharge of PEO coating and provides an available OD mode for preparing excellent PEO coating.

关键词： Magnesium alloy Plasma electrolytic oxidation coating Ordinal discharge Microstructure Performance