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Prevalence and risk factors of osteoporosis detected by dual-energy X-ray absorptiometry among Chinese patients with primary biliary cholangitis

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World Journal of Gastroenterology 2023年第29期29卷 4580-4592页

作者： Jia-Liang Chen Yao Liu Yu-Fei Bi Xian-Bo Wang Center of Integrative Medicine Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China

BACKGROUND Osteoporosis is an extrahepatic complication of primary biliary cholangitis(PBC)that increases the risk of fractures and mortality.However,Epidemiological studies of osteoporosis in patients with PBC in China and the Asia-Pacific region is lack.AIM To assess the prevalence and clinical characteristics of osteoporosis in Chinese patients with PBC.METHODS This retrospective analysis included consecutive patients with PBC from a tertiary care center in China who underwent bone mineral density(BMD)assessment using dual-energy X-ray absorptiometry between January 2013 and December 2021.We defined subjects with T-scores≤-2.5 in any sites(L1 to L4,femoral neck,or total hip)as having osteoporosis.Demographic,serological,clinical,and histological data were collected.Independent risk factors for osteoporosis were identified by multivariate logistic regression analysis.RESULTS A total of 268 patients with PBC[236 women(88.1%);mean age,56.7±10.6 years;163 liver biopsies(60.8%)]were included.The overall prevalence of osteoporosis in patients with PBC was 45.5%(122/268),with the prevalence of osteoporosis in women and men being 47.0%and 34.4%,respectively.The prevalence of osteoporosis in postmenopausal women was significantly higher than that in premenopausal women(56.3%vs 21.0%,P<0.001).Osteoporosis in patients with PBC is associated with age,fatigue,menopausal status,previous steroid therapy,body mass index(BMI),splenomegaly,gastroesophageal varices,ascites,Mayo risk score,histological stage,alanine aminotransferase,albumin,bilirubin,platelet and prothrombin activity.Multivariate regression analysis identified that older age,lower BMI,previous steroid therapy,higher Mayo risk score,and advanced histological stage as the main independent risk factors for osteoporosis in PBC.CONCLUSION Osteoporosis is very common in Chinese patients with PBC,allowing for prior screening of BMD in those PBC patients with older age,lower BMI,previous steroid therapy and advanced liver disease.

关键词： Primary biliary cholangitis Osteoporosis Bone mineral density Dual-energy X-ray absorptiometry Prevalence Chinese

Joint Optimization of Task Caching,Computation Offloading and Resource Allocation for Mobile Edge Computing

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China Communications 2022年第12期19卷 142-159页

作者： Zhixiong chen Zhengchuan chen Zhi Ren liang liang Wanli Wen Yunjian jia School of Microelectronics and Communication Engineering Chongqing UniversityChongqing400044 China Chongqing Key Laboratory of Space Information Network and Intelligent Information Fusion Chongqing400044 China National Mobile Communications Research Laboratory Southeast UniversityNanjing210096 China School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400065 China

Applications with sensitive delay and sizeable data volumes,such as interactive gaming and augmented reality,have become popular in recent years.These applications pose a huge challenge for mobile users with limited resources.Computation offloading is a mainstream technique to reduce execution delay and save energy for mobile users.However,computation offloading requires communication between mobile users and mobile edge computing(MEC) servers.Such a mechanism would difficultly meet users’ demand in some data-hungry and computation-intensive applications because the energy consumption and delay caused by transmissions are considerable expenses for users.Caching task data can effectively reduce the data transmissions when users offload their tasks to the MEC server.The limited caching space at the MEC server calls for judiciously decide which tasks should be cached.Motivated by this,we consider the joint optimization of computation offloading and task caching in a cellular network.In particular,it allows users to proactively cache or offload their tasks at the MEC server.The objective of this paper is to minimize the system cost,which is defined as the weighted sum of task execution delay and energy consumption for all users.Aiming at establishing optimal performance bound for the system design,we formulate an optimization problem by jointly optimizing the task caching,computation offloading,and resource allocation.The problem is a challenging mixed-integer non-linear programming problem and is NP-hard in general.To solve it efficiently,by using convex optimization,Karmarkar ’s algorithm and the proposed fast search algorithm,we obtain an optimal solution of the formulated problem with manageable computational complexity.Extensive simulation results show that in comparison to some representative benchmark methods,the proposed solution can effectively reduce the system cost.

关键词： mobile edge computing computation offloading caching resource allocation

Correlation between indoor and outdoor corrosion tests for coal train body steel in a coal medium environment

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Journal of Iron and Steel Research(International) 2022年第9期29卷 1495-1504页

作者： jia-liang Song Jun-hang chen Pan Yi Na-na chen Zhao-liang Li Kui Xiao Institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Corrosion and Protection Center University of Science and Technology BeijingBeijing 100083China China Electric Power Research Institute Beijing 100192China

Q345B carbon steel as well as Q450NQR1 and S500AW weathering steels were subjected to outdoor exposure corrosion tests in coal environments and indoor periodic immersion accelerated corrosion tests with a simulated coal leaching solution.The corrosion kinetics were studied by the weight loss method,and the corrosion morphology and corrosion product composition were observed and analyzed by scanning electron microscopy,energy-dispersive spectroscopy and X-ray diffraction.Afterward,correlation analysis of the indoor and outdoor tests was carried out by the gray correlation analysis method.The results show that the relationship between the corrosion weight loss and corrosion time of the three steels conforms to follow the exponent power law.In particular,Q450NQR1 steel has the best corrosion resistance.The types of corrosion products and the distribution of elements in the rust layer of the three steels are similar in the indoor and outdoor tests.The gray correlation degrees of the three steels in the indoor and outdoor tests are all greater than 0.6;thus,the two corrosion tests have a good correlation.Based on this,the accelerated simulation test method of the coal leaching solution is determined,and life prediction models of three steels in coal leaching solution are established to simulate the corrosion of the bottom board and side board.

关键词： Coal train body steel Coal environment-Corrosion Outdoor exposure test Indoor acceleration test Correlation

Dication-accelerated anion transport inside micropores for the rapid decontamination of pertechnetate

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Nuclear Science and Techniques 2022年第4期33卷 19-32页

作者： Peng Zhang Yi-Zhi chen Han-Qin Weng Zi-Fang Guo Jia-Liang Chen Xing Zhao Guo-An Ye Ming-Zhang Lin School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China Department of Beam Material Science SANKENThe Institute of Scientific and Industrial ResearchOsaka University8-1 MihogaokaIbarakiOsaka 567-0047Japan Radiochemistry Department of China Institute of Atomic Energy China Institute of Atomic EnergyBeijing 102413China

Over 70%of the treated contaminated water at the Fukushima Daiichi Nuclear Power Station contains radionuclides beyond the regulatory standard for discharge that need to be re-purified.Technetium-99(^(99)Tc),mainly in the form of pertechnetate Tc(VII)O_(4)^(-),is one of the main sources of long-term radiotoxicity that jeopardizes the environment and human health.Herein,we used a series of dicationic pyridinium(DCP)derivative groups(–Py^(+)C_(n)H_(2n)N^(+)Me_(3),n=2,3,and 5)to modify commercial Reillex 425 resins containing tertiary pyridyl groups to improve the adsorption performance of rhenium(Re,an analog of radioactive Tc)and Tc.As the quaternary pyridinium and ammonium sites in one DCP group can adsorb ReO_(4)^(-) simultaneously,DCP-modified Reillex 425(Reillex-Cn)exhibited high maximum adsorption capacities for Re under neutral conditions.Adsorption capacities reached 344.8,416.7,and 588.2 mg g^(-)1 for Reillex 425-C2,Reillex 425-C3,and Reillex 425-C5,respectively.Intraparticle diffusion of ReO_(4)^(-)/TcO_(4)^(-) in Reillex 425-Cn was verified to be the rate-limiting step of adsorption.However,adsorption can be adjusted by the length of the alkyl spacers between the two positively charged N sites in DCP.–Py^(+)C_(2)H_(4)N^(+)Me_(3) significantly enhanced intraparticle diffusion compared to–Py^(+)C_(5)H_(10)N^(+)Me_(3).The two positive sites in–Py^(+)C_(2)H_(4)N^(+)Me_(3) would be laterally distributed,leading to a smaller steric hindrance for ReO_(4)–/TcO_(4)^(-) transport inside the microporous channels.Meanwhile,the longer alkyl spacers in–Py^(+)C_(5)H_(10)N^(+)Me_(3) formed hydrophobic microphases,repulsing the hydrated ReO_(4)–/TcO_(4)^(-) anions.Thus,the adsorptions of both ReO_(4)^(-) and TcO_(4)^(-) on Reillex 425-C2 were faster than those on Reillex 425-C5.Moreover,Reillex 425-Cn exhibited an exothermic nature,good selectivity,excellent reusability,and strong salinity tolerance.This study provides a simple strategy to enhance the Tc removal performance of adsorbents containing abundant micropores,wh

关键词： Quaternary pyridinium Dicationic pyridyl derivatives Pertechnetate Intraparticle diffusion

Digital signal acquisition system for complex nuclear reaction experiments

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Nuclear Science and Techniques 2024年第1期35卷 124-133页

作者： Wei-liang Pu Yan-Lin Ye jian-Ling Lou jia-Hao chen School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Institute of Applied Physics and Computational Mathematics Beijing 100094China

A digital data-acquisition system based on XIA LLC products was used in a complex nuclear reaction experiment using radioactive ion beams.A flexible trigger system based on a field-programmable gate array(FPGA)parametrization was developed to adapt to different experimental sizes.A user-friendly interface was implemented,which allows converting script language expressions into FPGA internal control parameters.The proposed digital system can be combined with a conventional analog data acquisition system to provide more flexibility.The performance of the combined system was veri-fied using experimental data.

关键词： Digital signal acquisition system Trigger Programmable logic Timestamp

Bulky Thiolate-Protected Silver Nanocluster Ag_(213)(Adm-S)_(44)Cl_(33)with Excellent Electrocatalytic Performance toward Oxygen Reduction

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CCS Chemistry 2023年第5期5卷 1154-1162页

作者： chen-Guang Shi jian-Hua jia Yaling jia Guangqin Li Ming-liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-sen UniversityGuangzhouGuangdong 510006

Atomically precise gold and/or silver nanoclusters play a key role in crystallography and coordination chemistry.Compared with gold nanoclusters,silver nanoclusters become unstable and difficult to crystallize due to the high reactivity ofmetal silver.Herein,we report a silver nanocluster Ag_(213)(Adm-S)_(44)Cl_(33)(Ag_(213))coprotected by bulky thiolates and chlorides.The low surface thiolate coverage(about 45%)endows Ag_(213)with high catalytic activity.Supported on activated carbon,Ag_(213)nanoclusters exhibit excellent electrocatalytic oxygen reduction performance with Eonset and E_(1/2)values of 0.89 and 0.72 V,respectively,close to the values of commercial Pt/C catalyst.This is the first report on the electrocatalytic oxygen reduction reaction of nanoclusters with more than 100 silver atoms.Ag_(213)with the diameter of 2.75 nm comprises a core–shell structure Ag_(7)@Ag_(32)@Ag_(77)@Ag_(97).The strong plasmonic absorption band at 454 nm reveals the metallic nature of Ag_(213).Interestingly,halide is of importance.Chloride facilitates the formation of Ag_(213)and Ag_(56)(Adm-S)_(33)Cl_(16)(Ag_(56)^(Cl))while bromide can promote the formation of Ag_(56)(Adm-S)_(33)Br_(16)(Ag_(56)Br).This work provides an example for the study of largesized metal nanoclusters and nanocluster-based electrocatalysts.

关键词： silver nanoclusters atomically precise structure oxygen reduction reaction electrocatalysis

DPPS: A novel dual privacy-preserving scheme for enhancing query privacy in continuous location-based services

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Frontiers of Computer Science 2023年第5期17卷 197-205页

作者： Long LI jianbo HUANG liang CHANG jian WENG jia chen Jingjing LI College of Cyber Security Jinan UniversityGuangzhou 510632China Guangxi Key Laboratory of Trusted Software Guilin University of Electronic TechnologyGuilin 541004China Department of Computer Applications Guilin University of Technology at NanningNanning 530000China

Since smartphones embedded with positioning systems and digital maps are widely used,location-based services(LBSs)are rapidly growing in popularity and providing unprecedented convenience in people’s daily lives;however,they also cause great concern about privacy leakage.In particular,location queries can be used to infer users’sensitive private information,such as home addresses,places of work and appointment locations.Hence,many schemes providing query anonymity have been proposed,but they typically ignore the fact that an adversary can infer real locations from the correlations between consecutive locations in a continuous LBS.To address this challenge,a novel dual privacy-preserving scheme(DPPS)is proposed that includes two privacy protection mechanisms.First,to prevent privacy disclosure caused by correlations between locations,a correlation model is proposed based on a hidden Markov model(HMM)to simulate users’mobility and the adversary’s prediction probability.Second,to provide query probability anonymity of each single location,an advanced k-anonymity algorithm is proposed to construct cloaking regions,in which realistic and indistinguishable dummy locations are generated.To validate the effectiveness and efficiency of DPPS,theoretical analysis and experimental verification are further performed on a real-life dataset published by Microsoft,i.e.,GeoLife dataset.

关键词： location-based services privacy-preserving hidden Markov model k-anonymity query probability

Selective lithium recovery from black powder of spent lithiumion batteries via sulfation reaction:phase conversion and impurities influence

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Rare Metals 2023年第7期42卷 2350-2360页

作者： Hao Liu jia-liang Zhang Guo-Qiang liang Meng Wang Yong-Qiang chen cheng-Yan Wang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Green Recycling and Extraction of Metals Beijing100083China

The aim of this study is to present a new understanding for the selective lithium recovery from spent lithium-ion batteries(LIBs)via sulfation roasting.The composition of roasting products and reaction behavior of impurity elements were analyzed through thermodynamic calculations.Then,the effects of sulfuric acid dosage,roasting temperature,roasting time,and impurity elements were assessed on the leaching efficiency of valuable metals.Characterization methods such as X-ray diffraction(XRD),scanning electron microscopy-energy dispersive spectroscopy(SEM-EDS),and X-ray photoelectron spectroscopy(XPS)were employed to analyze the phase transformation mechanism during roasting process.The results indicate that after sulfation roasting(n(H_(2)SO_(4)):n(Li)=0.5,550℃,2 h),94%lithium can be selectively recovered by water leaching and more than 95%Ni,Co,and Mn can be leached through acid leaching without the addition of reduction agent.During the sulfation roasting process,the lithium in LiNi_(x)Mn_(y)Co_zO_(2)is mainly converted to Li_(2)SO_(4),while the Ni,Co and Mn are first transformed to sulfate and then converted into oxide form.In addition,impurity elements such as Al and F will combine with lithium to form LiF and LiAlO_(2),which will reduce the leaching rate of lithium.These results provide a new understanding on the mechanisms of phase conversion during sulfation roasting and reveal the influence of impurity elements for the lithium recovery from spent LIBs.

关键词： Spent lithium-ion batteries(LIBs) Thermodynamic calculations Sulfation roasting Impurity elements Conversion mechanism

Efficient 3D Hilbert Curve Encoding and Decoding Algorithms

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Chinese Journal of Electronics 2022年第2期31卷 277-284页

作者： jia Lianyin liang Binbin LI Mengjuan LIU Yong chen Yinong DING jiaman Faculty of Information Engineering and Automation Kunming University of Science and Technology Yunnan Key Laboratory of Artificial Intelligence Kunming University of Science and Technology Library Yunnan Normal University School of Information Science and Engineering Guangxi University for Nationalities School of Computing Informatics and Decision Systems Arizona State University

Hilbert curve describes a one-to-one mapping between multidimensional space and 1 D space.Most traditional 3D Hilbert encoding and decoding algorithms work on order-wise manner and are not aware of the difference between different input data and spend equivalent computing costs on them, thus resulting in a low efficiency. To solve this problem, in this paper we design efficient 3D state views for fast encoding and decoding. Based on the state views designed, a new encoding algorithm(JFK-3HE) and a new decoding algorithm(JFK-3HD) are proposed. JFK-3HE and JFK-3HD can avoid executing iteratively encoding or decoding each order by skipping the first 0 s in input data, thus decreasing the complexity and improving the efficiency. Experimental results show that JFK-3HE and JFK-3HD outperform the state-of-the-arts algorithms for both uniform and skew-distributed data.

关键词： 3D Hilbert curve Space-filling curve state view JFK-3HE JFK-3HD