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The Influence of Different Solar System Planetary ephemerides on Pulsar Timing

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Research in Astronomy and Astrophysics 2024年第8期24卷 85-99页

作者： Jian-Peng Dai Wei Han na Wang School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China

Pulsar timing offers a comprehensive avenue for exploring diverse topics in physics and *** solar system planetary ephemeris is crucial for pulsar timing as it provides the positions and velocities of solar system planets including the ***,it is inevitable that inherent inconsistencies exist in these *** between various ephemerides can significantly impact pulsar timing and parameter ***,pulsar timing highly depends on the JPL De ephemeris,for instance,the Pulsar Timing Array data analysis predominantly utilizes *** this study,we examine inconsistencies across various ephemeris series,including JPL De,ePM,and ***,discrepancies emerge particularly between the current ephemeris De436 and the earliest released ephemeris De200,as well as the most recent ephemerides,e.g.,De440,INPOP21A,and *** detailed analysis of the effects of ephemeris on geometric correction procedures for the conversion of measured topocentric times of arrival is presented in this *** researches reveal that variations in the Roemer delays across different ephemerides lead to distinct *** timing residuals and the fact that these discrepancies can be readily incorporated into the subsequent pulsar parameters,leading to inconsistent fitting estimates,suggest that the influence of errors in the ephemeris on the timing process might currently be underappreciated.

关键词： (stars)pulsars general-Planetary Systems-time-ephemerides

Using deep neural networks coupled with principal component analysis for ore production forecasting at open-pit mines

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Journal of Rock Mechanics and Geotechnical engineering 2024年第3期16卷 727-740页

作者： Chengkai Fan na Zhang Bei Jiang Wei Victor Liu Department of Civil and environmental engineering University of AlbertaEdmontonAlbertaT6G 2E3Canada Department of Mathematical and Statistical Sciences University of AlbertaEdmontonAlbertaT6G 2G1Canada

Ore production is usually affected by multiple influencing inputs at open-pit ***,the complex nonlinear relationships between these inputs and ore production remain *** becomes even more challenging when training data(*** haulage information and weather conditions)are *** machine learning(ML)algorithms,deep neural network(DNN)is a superior method for processing nonlinear and massive data by adjusting the amount of neurons and hidden *** study adopted DNN to forecast ore production using truck haulage information and weather conditions at open-pit mines as training *** the prediction models were built,principal component analysis(PCA)was employed to reduce the data dimensionality and eliminate the multicollinearity among highly correlated input *** verify the superiority of DNN,three ANNs containing only one hidden layer and six traditional ML models were established as benchmark *** DNN model with multiple hidden layers performed better than the ANN models with a single hidden *** DNN model outperformed the extensively applied benchmark models in predicting ore *** can provide engineers and researchers with an accurate method to forecast ore production,which helps make sound budgetary decisions and mine planning at open-pit mines.

关键词： Oil sands production Open-pit mining Deep learning Principal component analysis(PCA) Artificial neural network Mining engineering

Multi-objective optimization and evaluation of supercritical CO_(2) Brayton cycle for nuclear power generation

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Nuclear Science and Techniques 2024年第2期35卷 183-209页

作者： Guo-Peng Yu Yong-Feng Cheng na Zhang Ping-Jian Ming Sino-French Institute of Nuclear engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China School of Civil engineering and Architecture East China Jiaotong UniversityNanchang 330013China

The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle *** models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear *** analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic *** show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic *** the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOe)of 0.012$/(kWh).The nuclear Brayton cycle system’s overall performance has been improved due to *** performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,*** performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited *** the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully.

关键词： Supercritical CO_(2)Brayton cycle Nuclear power generation Thermo-economic analysis Multi-objective optimization Decision-making methods

Oleanolic acid improved intestinal immune function by activating and potentiating bile acids receptor signaling in e. coli-challenged piglets

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Journal of Animal Science and Biotechnology 2024年第5期15卷 2137-2155页

作者： Chenyu Xue Hongpeng Jia Rujing Cao Wenjie Cai Weichen Hong Jianing Tu Songtao Wang Qianzhi Jiang Chongpeng Bi Anshan Shan na Dong The Laboratory of Molecular Nutrition and Immunity College of Animal Science and TechnologyNortheast Agricultural UniversityHarbinP.R.China

Background Infection with pathogenic bacteria during nonantibiotic breeding is one of the main causes of animal intestinal *** acid(OA)is a pentacyclic triterpene that is ubiquitous in *** previous work demonstrated the protective effect of OA on intestinal health,but the underlying molecular mechanisms remain *** study investigated whether dietary supplementation with OA can prevent diarrhea and intestinal immune dysregulation caused by enterotoxigenic escherichia coli(eTeC)in *** key molecular role of bile acid receptor signaling in this process has also been *** Our results demonstrated that OA supplementation alleviated the disturbance of bile acid metabolism in eTeC-infected piglets(Pementation stabilized the composition of the bile acid pool in piglets by regulating the enterohepatic circulation of bile acids and significantly increased the contents of UDCA and CDCA in the ileum and cecum(Pexplain why OA can maintain the stability of the intestinal microbiota structure in eTeC-challenged *** addition,as a natural ligand of bile acid receptors,OA can reduce the severity of intestinal inflammation and enhance the strength of intestinal epithelial cell antimicrobial programs through the bile acid receptors TGR5 and FXR(Pecifically,OA inhibited NF-κB-mediated intestinal inflammation by directly activating TGR5 and its downstream c AMP-PKA-CReB signaling pathway(Permore,OA enhanced CDCA-mediated MeK-eRK signaling in intestinal epithelial cells by upregulating the expression of FXR(Pereby upregulating the expression of endogenous defense molecules in intestinal epithelial *** In conclusion,our findings suggest that OA-mediated regulation of bile acid metabolism plays an important role in the innate immune response,which provides a new diet-based intervention for intestinal diseases caused by pathogenic bacterial infections in pig

关键词： Bile acid receptors enterotoxigenic escherichia coli Intestinal innate immunity Oleanolic acid

Transverse mode-coupling instability with longitudinal impedance

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Nuclear Science and Techniques 2024年第6期35卷 40-53页

作者： Hai-Sheng Xu Chun-Tao Lin na Wang Jing-Ye Xu Yuan Zhang Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Institute of Advanced Science Facilities Shenzhen 518107GuangdongChina

Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle *** mechanism of TMCI can be explained by the coupling of transverse coherent oscillation modes owing to the transverse short-range wakefield(i.e.,the transverse broadband impedance).Recent studies on future circular colliders,e.g.,FCC-ee,showed that the threshold of TMCI decreased significantly when both longitudinal and transverse impedances were *** performed computations for the circular electron-positron collider(CePC)and observed a similar *** studies on the influence of longitudinal impedance on the TMCI threshold were *** concluded that the imaginary part of the longitudinal impedance,which caused a reduction in the incoherent synchrotron tune,was the primary reason for the reduction in the TMCI ***,the real part of the longitudinal impedance assists in increasing the TMCI threshold.

关键词： Transverse mode-coupling instability Longitudinal impedance

Critical Role of ethylene-Propylene Block Copolymer in Impact Polypropylene Copolymer

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Chinese Journal of Polymer Science 2024年第3期42卷 344-351,I0007页

作者： Yu-Hui Tang na Zhang Wei Bao Wei Jiang Yuan Lin Zhao-Hui Su State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and engineering University of Science and Technology of ChinaHefei 230026China

ethylene-propylene block copolymer(ebP) is a vital component in impact polypropylene copolymer(IPC), yet its distribution in the multiphase composite material and how it influences the phase structure and the mechanical properties are not well understood. In this work,four IPCs were investigated by atomic force microscopy-infrared(AFM-IR) to assess the phase compositions in situ, based on which in conjunction with the chain microstructure information obtained ex situ the distributions of the copolymer components were derived for each alloy. For the IPCs whose ebP comprises long P and long e segments, the ebP fraction was found to phase separate from the rubber and the PP matrix to form the cores of the disperse particles with the e-P segmented copolymer(esP). In contrast, in the IPC with ebP composed of long P and short e segments, the ebP fraction formed an outer shell for the rubber particles with the cores comprising the esP alone, and this IPC, containing a lower e comonomer content than its counterpart, exhibited both better impact resistance and higher flexural modulus. These results clarify how the chain structure of ebP governs the phase morphology in IPC, which in turn impacts the properties of the composite material.

关键词： Impact polypropylene copolymers AFM-IR ethylene-propylene block copolymers Core-shell rubber particles

Insights into sensitizing and eliciting capacity of gastric and gastrointestinal digestion products of shrimp(Penaeus vannamei)proteins in BALB/c mice

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Food Science and Human Wellness 2024年第1期13卷 339-348页

作者： Yao Liu Songyi Lin Kexin Liu Shan Wang Wang Li na Sun national engineering Research Center of Seafood School of Food Science and TechnologyDalian Polytechnic UniversityDalian 116034China Collaborative Innovation Center of Seafood Deep Processing Dalian Polytechnic UniversityDalian 116034China

Shrimp(Penaeus vannamei)proteins have been shown an allergenic potential;however,little information is available on the sensitizing and eliciting capacity of shrimp protein digestion *** this study,a BALB/c mice model was used to explore the allergenicity of shrimp protein sample(SPS)and their gastric and gastrointestinal digestion products(GDS/GIDS).As compared with the SPS groups,the GDS/GIDS groups caused lower specific immunoglobulins(Ig e/Ig G1)levels(Per than the control groups,indicating that the digestion products sensitized the ***,spleen index,mouse mast cell protease-1(m MCP-1)concentration and proportion of degranulated mast cells were significantly reduced in the GDS/GIDS groups(Peously,allergic symptoms,vascular permeability and histopathological changes of tissues were ***,the allergenicity of digestion products cannot be eliminated and still cause systemic allergic reactions in *** study showed that the digestion products of shrimp still had high sensitizing and eliciting capacity.

关键词： Penaeus vannamei Allergenicity Digestion BALB/c mice model

efficient and selective upcycling of waste polylactic acid into acetate using nickel selenide

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Journal of energy Chemistry 2024年第10期97卷 575-584页

作者： Bing Lan Yinfang Chen nantian Xiao na Liu Chao Juan Chuan Xia Fan Zhang national engineering Laboratory of eco-Friendly Polymeric Materials College of Chemistry Sichuan University School of Materials and energy University of Electronic Science and Technology of China

The conversion of waste polylactic acid（PLA） plastics into high-value-added chemicals through electrochemical methods is a promising and sustainable ***,developing efficient and highly selective catalysts for lactic acid oxidation reaction（LAOR） and understanding the reaction process are ***,we report the electrooxidation of waste PLA to acetate at a high current density of 100 mA cm-2 with high Faraday efficiency（～95%） and excellent stability（>100 h） over a nickel selenide nanosheet *** addition,a total Faraday efficiency of up to 190% was achieved for carboxylic acids,including acetic acid and formic acid,by coupling with the cathodic CO2reduction *** situ experimental results and theoretical simulations revealed that the catalytic activity center of LAOR was dynamically formed NiOOH species,and the surface-adsorbed SeOxspecies accelerated the formation of Ni3+species,thus promoting catalytic *** mechanism of lactic acid electrooxidation was further *** acid was dehydrogenated to produce pyruvate first and then formed CH3CO due to preferential C-C bond cleavage,resulting in the presence of *** work demonstrated a sustainable method for recycling waste PLA and CO2into high-value-added products.

关键词： Acetic acid Lactic acid electro-oxidation Poly (lactic acid) Waste plastic upcycling

efficacy and safety of electroacupuncture for insomnia:A systematic review and meta-analysis

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Journal of Integrative Medicine 2024年第4期22卷 459-472页

作者： Han-yu Xu Lin-na Wu Yuan Zhang Te Ba Xiao-feng Zhao Acupuncture and Moxibustion Department First Teaching Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300193China national Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion Tianjin 300193China

Background:electroacupuncture is often used to treat ***:To evaluate the efficacy and safety of electroacupuncture for *** strategy:Databases including PubMed,Cochrane Library,embase,Web of Science,Chinese Biomedical Literature Database,China national Knowledge Infrastructure,Wanfang Data and VIP Fulltext e-Journals Database were searched up to January 15,*** criteria:Randomized clinical trials were included if they compared the clinical efficacy and safety of electroacupuncture with sham acupuncture,no treatment or usual care (UC) and general *** extraction and analysis:The full texts of the studies were reviewed to remove ineligible *** extracted data included authors,publication year,diagnostic criteria,sample size,population characteristics,interventions and *** above steps were performed independently by two reviewers and the data were cross ***15.0 software was used to analyze the extracted outcome *** continuous data (Pittsburgh Sleep Quality Index[PSQI]score and Insomnia Severity Index score),weighted mean difference (WMD) was calculated and 95% confidence interval (CI) was reported when the same scale was *** dichotomous variables (clinical response rate and adverse events),a meta-analysis was performed using risk ratio (RR) as the effect ***:Thirty-one trials with 2226 subjects were *** meta-analysis suggested that electroacupuncture was more effective in improving insomnia compared with the control group (sham acupuncture,no treatment,UC and general acupuncture)(RR=1.21;95 CI:[1.16,1.27]),significantly reducing the PSQI score in insomnia patients after treatment and at follow-up (WMD=-3.23;95%CI:[-4.29,-2.17];Pere was no significant difference in the incidence of adverse events between the eA and control groups (sham acupuncture and no treatment or ***=1.48;95%CI:[0.91,2.40];P=0.117).In addition,the regression results revealed t

关键词： electroacupuncture Insomnia Systematic review Meta-analysis