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A Blockchain-Based Protocol for Malicious Price Discrimination

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Journal of Computer Science & Technology 2022年第1期37卷 266-276页

作者： Li-De Xue ya-jun liu Wei yang Wei-Lin Chen liu-Sheng Huang School of Computer Science and Technology University of Science and Technology of ChinaHefei 230000China Information Department the First Affiliated Hospital of Soochow UniversitySuzhou 215000China

Serious price discrimination emerges with the development of big data and mobile networks,which harms the interests of *** solve this problem,we propose a blockchain-based price consensus protocol to solve the malicious price discrimination faced by *** give a mathematical definition of price discrimination,which requires the system to satisfy consistency and *** distributed blockchain can make the different pricing of merchants transparent to consumers,thus satisfying the *** aging window mechanism of our protocol ensures that there is no disagreement between any node on the consensus on price or price discrimination within a fixed period,which meets the ***,we evaluate its performance through a prototype implementation and experiments with up to 100 user *** results show that our protocol achieves all the expected goals like price transparency,consistency,and timeliness,and it additionally guarantees the consensus of the optimal price with a high probability.

关键词： blockchain digital economy distributed application price discrimination price transparency

Shortening the delivery time of proton therapy by real-time compensation method with raster scanning

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Nuclear Science and Techniques 2022年第6期33卷 62-74页

作者： Xiang-Shang Sun Yong-Jiang Li jun-ya liu Wen-Tao Liao Chao Wu Yue-Hu Pu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai APACTRON Particle Equipment Co. LtdShanghai 201800China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Medical Equipment Innovation Research Center West China HospitalSichuan UniversityChengdu 610041China

Among the various scanning techniques, spot and raster scanning are the most frequently adopted. Raster scanning turns off the beam only when each isoenergy slice irradiation is completed. This feature intrinsically solves the leakage dose and frequent beam-switching problems encountered during spot scanning. However, to shorten the delivery time of raster scanning, a sophisticated dose control strategy is required to guarantee dose *** this study, a real-time compensation method with raster scanning for synchrotron systems was designed. It is characterized by a small spot-spacing planning strategy and real-time subtraction of the transient number of particles delivered between two planning-spot positions from the planned number of particles of the subsequent raster *** efficacy of the compensation method was demonstrated by performing accurate raster scanning simulations with an in-house simulation code and accurate final dose evaluations with a commercial treatment planning *** the similar dose evaluation criteria under a practical high scanning speed, compared with the spot scanning method, the total delivery time of the compensated raster scanning method was significantly shortened by 53.3% in the case of irradiating a cubical target and by 28.8% in a pelvic case. Therefore, it can be concluded that real-time compensated raster scanning with a fast scanning configuration can significantly shorten the delivery time compared to that of spot scanning. It is important to reduce the pressure on patients caused by prolonged immobilization and to improve patient throughput capacity at particle therapy centers.

关键词： Proton therapy Raster scanning Delivery time Scanning simulation

QM/MM Study on Enzymatic Mechanism in Sinigrin Biosynthesis

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Chinese Journal of Chemical Physics 2022年第1期35卷 193-199,I0041-I0057,I0064页

作者： ya-Jie Guo ya-jun liu Key Laboratory of Theoretical and Computational Photochemistry Ministry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China Center for Advanced Materials Research Advanced Institute of Natural SciencesBeijing Normal University at ZhuhaiZhuhai 519087China

As the major and abundant type of glucosinolates(GL)in plants,sinigrin has potential functions in promoting health and insect *** final step in the biosynthesis of sinigrin core structure is highly representative in GL compounds,which corresponds to the process from 3-methylthiopropyl ds-GL to 3-methylthiopropyl GL catalyzed by sulfotransferase(SOT).However,due to the lack of the crystallographic structure of SOT complexed with the 3-methylthiopropyl GL,little is known about this sulfonation ***,the crystal structure of SOT 18 from Arabidopsis thaliana(At SOT18)containing the substance(sinigrin)similar to 3-methylthiopropyl GL has been *** understand the enzymatic mechanism,we employed molecular dynamics(MD)simulation and quantum mechanics combined with molecular mechanics(QM/MM)methods to study the conversion from ds-sinigrin to sinigrin catalyzed by *** calculated results demonstrate that the reaction occurs through a concerted dissociative ***,Lys93,Thr96,Thr97,Tyr130,His155,and two enzyme peptide chains(Pro92-Lys93 and Gln95-Thr96-Thr97)play a role in positioning the substrates and promoting the catalytic reaction by stabilizing the transition state ***,His155 acts as a catalytic base while Lys93 acts as a catalytic acid in the reaction *** presently proposed concerted dissociative mechanism explains the role of At SOT18 in sinigrin biosynthesis,and could be instructive for the study of GL biosynthesis catalyzed by other SOTs.

关键词： Sinigrin Sulfotransferase Molecular dynamics Quantum mechanics and molecular mechanics

A New Epidithiodioxopiperazine Metabolite Isolated from Gliocladium roseum YMF1.00133

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Chinese Chemical Letters 2006年第7期17卷 922-924页

作者： Jin yah DONG Wei ZHOU Lei LI Guo Hong LI ya jun liu Ke Qing ZHANG Laboratory for Conservation and Utilization of Bioresources Yunnan University Kunming 650091

Glioclatine, a novel epidithiodioxopiperazine was isolated from wheat solid-substrate fermentation of Gliocladium roseum YMF1.00133. Its structure was elucidated by HRESI-MS and NMR spectra.

关键词： Glioclatine epidithiodioxopiperazine Gliocladium roseum.

Cross-talk between microRNA-let7c and transforming growth factor-β2 during epithelial-to-mesenchymal transition of retinal pigment epithelial cells

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International Journal of Ophthalmology(English edition) 2020年第5期13卷 693-700页

作者： Qu-Zhen Deji Feng yan Wang-Dui Zhaba ya-jun liu Jie Yin Zhen-Ping Huang Department of Ophthalmology Affiliated Jinling HospitalMedical School of Nanjing UniversityNanjing 210002Jiangsu ProvinceChina Department of Neurosurgery Affiliated Jinling HospitalMedical School of Nanjing UniversityNanjing 210002Jiangsu ProvinceChina Department of Ophthalmology Affiliated Drum Tower HospitalMedical School of Nanjing UniversityNanjing 210008Jiangsu ProvinceChina

AIM: To explore the roles of microRNA-let7 c(miR-let7 c) and transforming growth factor-β2(TGF-β2) and cellular signaling during epithelial-to-mesenchymal transition(EMT) of retinal pigment epithelial cells. METHODS: Retinal pigment epithelial(ARPE-19) cells were cultured with no serum for 12 h, and then with recombinant human TGF-β2 for different lengths of time. ARPE-19 cells were transfected with 1×106 TU/mL miR-let7 c mimcs(miR-let7 cM), miR-let7 c mimcs negative control(miR-let7cMNC) and miR-let7 c inhibitor(miR-let7 cI) using the transfection reagent. The expression of keratin-18, vimentin, N-cadherin, IKB alpha, p65 were detected by Western blot, quantitative polymerase chain reaction and immunofluorescence. RESULTS: The expression of miR-let7c was dramatically reduced and the nuclear factor-kappa B(NF-κB) signaling pathway was activated after induction by TGF-β2(P<0.05). In turn, overexpressed miR-let7 c significantly inhibited TGF-β2-induced EMT(P<0.05). However, miR-let7 c was unable to inhibit TGF-β2-induced EMT when the NF-κB signaling pathway was inhibited by BAY11-7082(P<0.01). CONCLUSION: The miR-let7 c regulates TGF-β2-induced EMT through the NF-κB signaling pathway in ARPE-19 cells.

关键词： microRNA-let7c transforming growth factor-β2 epithelial-to-mesenchymal transition human retinal pigment epithelial cells nuclear factor-kappa B pathway

The role of mechanical stretch and TGF-β2 in epithelial-mesenchymal transition of retinal pigment epithelial cells

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International Journal of Ophthalmology(English edition) 2019年第12期12卷 1832-1838页

作者： Qian Cao Qu-Zhen Deji ya-jun liu Wei Ye Wang-Dui Zhaba Qin Jiang Feng yan Eye Hospital Nanjing Medical UniversityNanjing 210002Jiangsu ProvinceChina The Fourth School of Clinical Medicine Nanjing Medical UniversityNanjing 210002Jiangsu ProvinceChina Affiliated Jinling Hospital Medical School of Nanjing UniversityNanjing 210002Jiangsu ProvinceChina Departm ent of Ophthalm ology N anjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210008Jiangsu ProvinceChina School of Second Military Medical University Department of OphthalmologyJinling HospitalNanjing 210002Jiangsu ProvinceChina

AIM: To explore the effects and mechanisms of mechanical stress and transforming growth factor-beta2(TGF-β2) on epithelial-mesenchymal transition(EMT) in cultured human retinal pigment epithelial(RPE) cells. METHODS: Human RPE cells were inoculated on BioF ex 6-well plates and RPE cells received 0, 1, 2, 3, or 4 mild stretch injuries delivered 3h apart after 24h of culture. The device of mechanical stress parameters were set to sine wave, frequency 1 Hz, stretch strength 20%. For treatment with TGF-β2, when the inoculated RPE cells in 6-well plates were around 60% confluent, serum was reduced to 0 for 12h and recombinant human TGF-β2(0, 1, 5, 10 ng/mL)was added for 48h. α-SMA, Vimentin and N-Cadherin, fibronectin proteins expressions were detected by Western blotting, confocal cell immunofluorescence and quantitative real-time polymerase chain reaction(q RT-PCR). Then we detected the change of mi RNA-29b and ascertained the changes of phosphatidylinositol 3-kinase-serine threonine protein kinase(PI3K/Akt) pathway after RPE cells were stretched by the device of mechanical stress and induced by TGF-β2 by Western blotting, confocal cell immunofluorescence and qR T-PCR. RESULTS: Mechanical stress induce EMT and activate the PI3K/Akt pathway in ways that lead to the EMT process. TGF-β2 induce RPE cells EMT and in a certain range and TGF-β2 decrease the miR NA-29b expression in RPE cells, and the inhibitory effect is more obvious with the increase of TGF-β2 concentration. CONCLUSION: Our findings are crucial steps in determining the critical roles of the PI3K/Akt signaling pathway and mi RNA-29b in pathogenesis of proliferative vitreoretinopathy(PVR) which may be a potential target for preventing or treating PVR.

关键词： mechanical stress transforming growth factor-beta2 microRNA 29b epithelial-mesenchymal transition phosphatidylinositol 3-kinase-serine threonine protein kinase pathway proliferative vitreoretinopathy

Long-term clinical effects of intravitreal injections of conbercept for the treatment of choroidal neovascularization in patients with pathological myopia

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International Journal of Ophthalmology(English edition) 2022年第12期15卷 1971-1977页

作者： Si Zhang Zi-Fang He Fei-Fei Chen Wen-Wen Zhang ya-jun liu Hui Chen Zheng-Gao Xie Nanjing Drum Tower Hospital the Affiliated Hospital of Nanjing University Medical SchoolNanjing 210008Jiangsu ProvinceChina

AIM:To observe the long-term clinical efficacy of intravitreal injections of conbercept,a novel vascular growth factor inhibitor,for the treatment of pathological myopia choroidal neovascularization(PM-CNV).METHODS:A total of 67 eyes(from 67 patients;mean age,54.90±12.7y)with PM-CNV were retrospectively *** on the different schemes used for the administration of the drug,the patients were divided into two groups:group A(n=35;average age,53.31±13.6y;average diopter,9.25±1.72 D),which received only one injection of pro re nata(PRN;1+PRN regimen),and group B(n=32;average age,56.49±11.8y;average diopter,9.63±2.24 D),which received one injection per month for 3mo(3+PRN regimen).Best-corrected visual acuity(BCVA)analysis,intraocular pressure(IOP)examination,slit-lamp microscopy,fundus examination and optical coherence tomography were per formed at each *** recurrence and treatment times of CNV were *** patients were followed up for at least ***:The BCVA was increased in 29 eyes(82.9%)in group A and 30 eyes(93.75%)in group B;no increase or decrease was observed in 6(17.1%)and 2(6.25%)eyes in groups A and B,*** BCVA(log MAR)values before treatment(0.67±0.48 and 0.71±0.56)were significantly higher than those 12mo after treatment(0.31±0.26 and 0.33±0.17)in groups A and B,respectively(P<0.05).The mean central macular thickness(CMT)values had significantly decreased from 346.49±65.99 and 360.10±82.31μm at baseline to 257.29±40.47 and 251.97±48.26μm in groups A and B,respectively,after 12mo of treatment.A total of 21 eyes in group A needed reinjection(60%;average number of injections,2.51±0.98);the corresponding values in group B were 6 eyes(18.75%;average number of injections,3.74±1.22).There were no adverse ocular and systemic complications during the treatment and ***:Intravitreal injection of conbercept with 1+PRN or 3+PRN improve the visual acuity,reduce macular edema and reduce the level of CMT in patie

关键词： pathological myopia choroidal neovascularization conbercept best-corrected visual acuity central macular thickness

Robot-assisted Percutaneous Pedicle Screw Placement Using Three-dimensional Fluoroscopy： A Preliminary Clinical Study

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Chinese Medical Journal 2017年第13期130卷 1617-1618页

作者： Wei Tian Ming-Xing Fan ya-jun liu Department of Spine Surgery Beijing Jishuitan Hospital Beijing 100035 China

Pedicle screw placement is an advanced posterior fixation technique that can provide patients with great biomechanical benefits. However, the morphology of the vertebrae is complex and it is very difficult to insert screws without penetrating the cortex. Thus, new techniques for improving the accuracy of pedicle screw placement and safety are required. Herein,

关键词： Navigation Pedicle Screw Spine Surgical Robot

The Proton-Coupled Electron Transfer Reaction of Lumiflavin with Oxygen: Revealing the Oxygenation Mechanism in Bacterial Bioluminescence

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The Proton-Coupled Electron Transfer Reaction of Lumiflavin ...