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Using data-limited approaches to assess data-rich Indian Ocean bigeye tuna:Data quantity evaluation and critical information for management implications

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Acta Oceanologica Sinica 2022年第3期41卷 11-23页

作者： ya'nan li Jiangfeng Zhu Xiaojie Dai Dan Fu Yong Chen College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China School of Marine Sciences University of MaineOronoME 04469USA Key Laboratory of Oceanic Fisheries Exploration Ministry of Agriculture and Rural AffairsShanghai 201306China Indian Ocean Tuna Commission Victoria 361Seychelles

The majority of fishery stocks in the world are data limited,which limits formal stock assessments.Identifying the impacts of input data on stock assessment is critical for improving stock assessment and developing precautionary management strategies.We compare catch advice obtained from applications of various datalimited methods(DLMs)with forecasted catch advice from existing data-rich stock assessment models for the Indian Ocean bigeye tuna(Thunnus obesus).Our goal was to evaluate the consistency of catch advice derived from data-rich methods and data-limited approaches when only a subset of data is available.The Stock Synthesis(SS)results were treated as benchmarks for comparison because they reflect the most comprehensive and best possible scientific information of the stock.This study indicated that although the DLMs examined appeared robust for the Indian Ocean bigeye tuna,the implied catch advice differed between data-limited approaches and the current assessment,due to different data inputs and model assumptions.Most DLMs tended to provide more optimistic catch advice compared with the SS,which was mostly influenced by historical catches,current abundance and depletion estimates,and natural mortality,but was less sensitive to life-history parameters(particularly those related to growth).This study highlights the utility of DLMs and their implications on catch advice for the management of tuna stocks.

关键词： stock assessment bigeye tuna data-limited fisheries management Indian Ocean

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Hepatic MR imaging using IDEAL-IQ sequence:Will Gd-EOB-DTPA interfere with reproductivity of fat fraction quantification?

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世界临床病例杂志 2023年第25期11卷 5887-5896页

作者： Yuan Tian Peng-Fei liu Jia-Yu li ya-nan li Peng Sun Department of Magnetic Resonance Imaging The First Affiliated Hospital of Harbin Medical UniversityHarbin 150001Heilongjiang ProvinceChina

BACKGROUND Iterative decomposition of water and fat with echo asymmetry and least squares estimation quantification sequence(IDEAL-IQ)is based on chemical shift-based water and fat separation technique to get proton density fat fraction.Multiple studies have shown that using IDEAL-IQ to test the stability and repeatability of liver fat is acceptable and has high accuracy.AIM To explore whether Gadoxetate Disodium(Gd-EOB-DTPA)interferes with the measurement of the hepatic fat content quantified with the IDEAL-IQ and to evaluate the robustness of this technique.METHODS IDEAL-IQ was used to quantify the liver fat content at 3.0T in 65 patients injected with Gd-EOB-DTPA contrast.After injection,IDEAL-IQ was estimated four times,and the fat fraction(FF)and R2* were measured at the following time points:Precontrast,between the portal phase(70 s)and the late phase(180 s),the delayed phase(5 min)and the hepatobiliary phase(20 min).One-way repeated-measures analysis was conducted to evaluate the difference in the FFs between the four time points.Bland-Altman plots were adopted to assess the FF changes before and after injection of the contrast agent.Pliver,spleen and spine showed no significant differences,and the measurements of hepatic FF yielded good consistency between T1 and T2[95%confidence interval:-0.6768%,0.6658%],T1 and T3(-0.3900%,0.3178%),and T1 and T4(-0.3750%,0.2825%).R2* of the liver,spleen and spine increased significantly after injection(Plity of the IDEAL-IQ sequence makes it available in the scanning interval to save time during multiphase examinations.

关键词： Gadoxetate Disodium Iterative decomposition of water and fat with echo asymmetry and least squares estimation quantification sequence Fat fraction Enhanced-Magnetic resonance imaging R2*

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Research on bubble trajectory and flow structure in helical-axial multiphase pump

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水动力学研究与进展B辑:英文版 2023年第3期35卷 533-548页

作者： Hui Quan Chen-xi Sun Kai Song ya-nan li Xiao-yi liu Xue-ling yang liang Wang College of Energy and Power Engineering Lanzhou University of TechnologyLanzhou 730050China College of Engineering Nihon UniversityKoriyamaFukushimaJapan Shenyang Shengtai Environmental Protection Technology Co.Ltd Shenyang 110122China

The oil-gas two-phase hybrid transportation technology is one of the innovative technology directions for the exploitation and transportation of marginal and deep ocean oilfields.The helical-axial multiphase pump is a key equipment for oil and gas extraction.At this stage,most of the research on this kind of pump focuses on the improvement of the structure and conveying performance.However,because of insufficient understanding of the flow behavior and mechanism of bubbles,it is easy to cause the gas-liquid separation.In this paper,the numerical simulation and test are combined to explore the changes in the bubble trajectory and flow structure of the helical-axial multiphase pump.The results shown that when the speed is lower than 1200 r/min,the bubble reaches the maximum volume at 1/2 of the midline of the impeller blade and it contact with the pressure surface,broken to the suction surface.When the rotation speed is higher than 1450 r/min,the number of bubbles in the impeller increases and the size decreases.The backflow occurs in the tip clearance and strength increases continuously.The research results have important significance for the theoretical design and engineering application of the helical-axial multiphase pump.

关键词： Helical-axial multiphase pump gas-liquid two-phase flow visualization experiment bubble trajectory flow structure

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Fractal characterization of pore structure and its influence on CH_(4) adsorption and seepage capacity of low-rank coals

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Frontiers of Earth Science 2022年第4期16卷 916-933页

作者： Guangyuan MU Haihai HOU Jiaqiang ZHANG Yue TANG ya-nan li Bin SUN Yong li Tim JONES Yuan YUAN Longyi SHAO State Key Laboratory of Coal Resources and Safe Mining and College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing 100083China College of Mining Liaoning Technical UniversityFuxin 123000China Oil&Gas Resource Survey Center China Geological SurveyMinistry of Land and ResourceBeijing 100029China Department of Coalbed Methane Research Institute of Petroleum Exploration and DevelopmentPetroChinaBeijing 100083China School of Earth and Environmental Sciences Cardiff UniversityCardiff CF103YEUK

The pore structures of coal can directly affect the adsorption and seepage capacity of coalbed methane(CBM),which therefore is an important influence on CBM exploration and development.In this study,the pore structures of low-rank coals from the Middle Jurassic Xishanyao Formation in the southern Junggar Basin were analyzed,and the fractal dimensions(D1,D2,D3 and D4 corresponding to pore sizes of 0-5 nm,5-100 nm,100-1000 nm and 1000-20000 nm,respectively)were calculated to quantitatively describe these coal pore structures.The results show that Xishanyao coal is characterized by open pore morphology,good pore connectivity and well-developed seepage pores and microfractures,which is beneficial to CBM seepage.The D1 and D2 can be used to characterize the pore surface and structure of adsorption pores respectively.The D3 and D4 can be used to represent the pore structure of seepage pores.Compared with adsorption pores,the structure of seepage pores is more affected by the change of coal rank.The D1 is better than D2 in characterizing the methane adsorption capacity.When D1>2.2,D1 is positively correlated with Langmuir volume(VL)and negatively correlated with Langmuir pressure(PL),while D2 shows a weak opposite trend.The coals with the higher D1 and lower D2 are associated with a higher VL,indicating the coal reservoir with more complex pore surfaces and simpler pore structures has stronger methane adsorption capacity.D4 is better than D3 in characterizing the methane seepage capacity.The porosity and permeability of coal reservoirs increase with the increase of D4,while D3 displays an opposite trend,which is mainly related to the well-developed microfractures.The well-developed fracture system enhances the seepage capacity of the Xishanyao coal reservoir.This study reveals the fractal characteristics of pore structure and its significant influence on adsorption and seepage capacity of low-rank coal.

关键词： southern Junggar Basin Middle Jurassic low-rank coal coalbed methane pore structure fractal dimensions

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Effect of the Addition of High li Concentration on the Microstructure and Mechanical Properties of Al-Mg-Si Alloys with Different Mg Contents

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Acta Metallurgica Sinica(English Letters) 2021年第12期34卷 1721-1733页

作者： Xiao-Kun yang Bai-Qing Xiong Xi-Wu li li-Zhen yan Zhi-Hui li Yong-An Zhang ya-nan li Kai Wen State Key Laboratory of Nonferrous Metals and Processes GRINM Group Co.LtdBeijing 100088China GRIMAT Engineering Institute Co. LTDBeijing 101407China General Research Institute for Nonferrous Metals Beijing 100088China

In the present work,the microstructural characteristics and mechanical properties of Al-1.5 Mg-0.6Si and Al-3.0 Mg-0.6Si alloy containing 3 wt%li were investigated by optical microscopy(OM),X-ray diffraction analysis(XRD),scanning electron microscopy(SEM),time of flight-secondary ion mass spectrometry(SIMS),transmission electron microscopy(TEM),and mechanical performance testing.The addition of li reduces the density of the base alloy by up to 8.4%.The residual second phases contain Mg and Si in the hot-rolled condition,but the Mg/Si atomic ratio decreases after quenching,which means that li substitute some of the Mg and convert Mg_(2)Si into a(Mg,li)_(2)Si phase during solution treatment.The results of SIMS observations confirm this.The high Mg-containing alloy has a more rapid hardening response compared to the low Mg-containing alloy.TEM observation reveals that theδ′-Al3li+β′′-Mg_(2)Si dual phases can be observed in the high Mg-containing alloy after aging for 100 h at 170°C.The higher Mg content enhances the precipitation of theδ′phase,which results in the high Mg-containing alloy having a larger average diameter size ofδ′particles and widerδ′-precipitate-free zones(δ′-PFZs).The mechanical properties are significantly improved with the elastic modulus increasing by more than 16.5%.However,the existence of large second phases and wideδ′-PFZs in li-containing alloys is detrimental to their ductility;as a result,their elongation is much lower than that of the base alloy.

关键词： Al-Mg-Si alloy li addition Microstructure Aging behavior Mechanical properties Secondary ion mass spectrometer

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nanosized Rh grown on single-walled carbon nanohorns for efficient methanol oxidation reaction

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Rare Metals 2022年第6期41卷 2108-2117页

作者： Xiang-Jie Guo Qi Zhang ya-nan li yang Chen Lu yang Hai-yan He Xing-Tao Xu Hua-Jie Huang Collegeof Mechanics and Materials Hohai University Nanjing 210098China International Center for Materials nanoarchitectonics(WPI-MANA) National Institute for Materials ScienceIbaraki 305-0044Japan

Reasonable design and controllable synthesis of non-Pt catalysts with high methanol oxidation activity are regarded as a valid way to promote the large-scale com-mercial applications of direct methanol fuel cells(DMFCs).Herein,we develop a convenient and cost-ef-fective approach to the successful fabrication of nanosized Rh grown on single-walled carbon nanohorns(Rh/SWCNH)as anode catalysts for DMFCs.The unique architectural configuration endows the as-obtained hybrids with a series of intriguing structural merits,including large specific surface areas,abundant opened holes,optimized electronic structures,homogeneous Rh dispersion,and good electrical conductivity.As a consequence,the resulting Rh/SWCNH catalysts exhibit exceptional elec-trocatalytic properties in terms of a large electrochemically active surface area of 102.5 m^(2)·g^(-1),a high mass activity of 784.0 mA·mg^(-1),as well as reliable long-term durability towards the methanol oxidation reaction in alkaline media,thereby holding great potential as alternatives for com-mercial Pt/carbon black and Pd/carbon black catalysts.

关键词： Rhodium Carbon nanohorns Electrocatalysts Methanol oxidation Fuel cells

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Gut microbiota of hepatitis B virus-infected patients in the immunetolerant and immune-active phases and their implications in metabolite changes

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World Journal of Gastroenterology 2022年第35期28卷 5188-5202页

作者： ya-nan li Na-ling Kang Jia-Ji Jiang Yue-Yong Zhu Yu-Rui liu Da-Wu Zeng Fei Wang Department of Hepatology Hepatology Research InstituteThe First Affiliated HospitalFujian Medical UniversityFuzhou 350001Fujian ProvinceChina Department of Pharmacy Fujian Geriatric HospitalFuzhou 350001Fujian ProvinceChina

BACKGROUND The microbes and metabolomics of microbiota dysbiosis in the gut in the different phases of hepatitis B virus(HBV) infection are not fully understood.AIM To investigate the specific gut microbiota and metabolites of the immune-tolerant(IT) and immune-active(IA) phases of chronic hepatitis B(CHB).METHODS Clinical fecal samples from healthy individuals and patients in the IT and IA phases of HBV infection were collected. Next, non-target metabolomics, bioinformatics, and 16S rDNA sequencing analyses were performed.RESULTS A total of 293 different metabolites in 14 phyla, 22 classes, 29 orders, 51 families, and 190 genera were identified. The four phyla of Firmicutes, Bacteroidetes, Actinobacteria, and Proteobacteria were the most abundant, accounting for 99.72%, 99.79%, and 99.55% in the healthy controls, IT-phase patients, and IA-phase patients, respectively. We further identified 16 genera with different richness in the IT phase and IA phase of HBV infection. Of the 134 named metabolites, 57 were upregulated and 77 were downregulated. A total of 101 different metabolic functions were predicted in this study, with 6 metabolic pathways having the highest enrichments, namely carbohydrate metabolism(14.85%), amino acid metabolism(12.87%), lipid metabolism(11.88%), metabolism of cofactors and vitamins(11.88%), xenobiotic biodegradation(9.9%), and metabolism of terpenoids and polyketides(7.92%).CONCLUSION These findings provide observational evidence of compositional alterations of the gut microbiome and some related metabolites in patients with IT-phase or IA-phase HBV infection. Further studies should investigate whether microbiota modulation can facilitate the progression of CHB and the cause-effect relationship between the gut microbiota and CHB.

关键词： Microbes Metabolomics Gut microbiota Immune-tolerant phase Hepatitis B virus

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Trends in operating room-based glaucoma procedures at a single eye center from 2016–2020

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International Journal of Ophthalmology(English edition) 2023年第2期16卷 208-214页

作者： Di Zhang Jin-Hong Miao ling-Ge Suo ya-nan li Xu-Hao Chen De-Fu Wu Qian-Ru Wu Chun Zhang Department of Ophthalmology Peking University Third HospitalBeijing 100191China Beijing Key Laboratory of Restoration of Damaged Ocular Nerve Peking University Third HospitalBeijing 100191China Beijing Tongren Eye Center Beijing Tongren HospitalBeijing Institute of OphthalmologyCapital Medical UniversityBeijing 100730China

AIM:To evaluate trends in glaucoma procedures at the Peking University Eye Center in 2016–2020.METHODS:A retrospective search of all glaucoma procedures performed at our institution were performed.Data were analyzed by calculating the absolute numbers and relative weightage of each procedure per year.RESULTS:The average age of glaucoma patients undergoing surgical procedures was 62.33±17.87y,and 55%were women.From 2016 to 2019,the number of surgical procedures performed in glaucoma patients showed an overall upward trend from 749 to 1460,although it decreased slightly in 2020(n=1393),probably due to the COVID-19 pandemic.The number of trabeculectomies did not change significantly in 2016(n=161)to 2018(n=164)but decreased in 2019(n=139)to 2020(n=121),indicating a reduction in its relative weightage among glaucoma procedures(from 21.50%to 8.69%).The number of glaucoma drainage device implantations and minimally invasive glaucoma surgeries both increased(50and 58 respectively in 2019),except in 2020.The number of transscleral cyclophotocoagulation procedures was relatively stable,increasing until 2017(n=218)and then decreasing.Cataract surgeries with or without glaucoma procedures accounted for a large number of the total surgeries,increasing from 247(32.97%)in 2016 to 967(69.42%),among which cataract extraction combined with goniosynechialysis was the most frequent.CONCLUSION:The overall increase in the number of operating room-based surgical procedures is significant.Trabeculectomy is one of the most commonly performed procedures,despite the relative decline in its weightage.Other procedures,including use of glaucoma drainage devices and mini shunts and minimally invasive glaucoma surgeries,are gaining greater acceptance.Notably,lensrelated surgery plays an important role in glaucoma management.

关键词： glaucoma surgery trends minimally invasive glaucoma surgery

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Au core-PtAu alloy shell nanowires for formic acid electrolysis

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Journal of Energy Chemistry 2022年第2期31卷 94-102页

作者： Qi Xue Xin-Yu Bai Yue Zhao ya-nan li Tian-Jiao Wang Hui-Ying Sun Fu-Min li Pei Chen Pujun Jin Shi-Bin Yin Yu Chen Key Laboratory of Macromolecular Science of Shaanxi Province Key Laboratory of Applied Surface and Colloid Chemistry(MOE)Shaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710062ShaanxiChina MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured MaterialsGuangxi UniversityNanning 530004GuangxiChina

Inefficient electrocatalysts and high-power consumption are two thorny problems for electrochemical hydrogen(H2)production from acidic water electrolysis.Herein we report the one-pot precise synthesis of ultrafine Au core-Pt Au alloy shell nanowires(Au@PtxAu UFNWs).Among them,Au@Pt_(0.077) Au UFNWs exhibit the best performance for formic acid oxidation reaction(FAOR)and hydrogen evolution reaction(HER),which only require applied potentials of 0.29 V and-22.6 m V to achieve a current density of 10 m A cm^(-2),respectively.The corresponding formic acid electrolyzer realizes the electrochemical H2 production at a voltage of only 0.51 V with 10 m A cm^(-2) current density.Density functional theory(DFT)calculations reveal that the Au-riched Pt Au alloy structure can facilitates the direct oxidation pathway of FAOR and consequently elevates the FAOR activity of Au@Pt_(0.077) Au UFNWs.This work provides meaningful insights into the electrochemical H_(2) production from both the construction of advanced bifunctional electrocatalysts and the replacement of OER.

关键词： Au core-PtAu alloy shell nanowires Formic acid oxidation reaction Reaction pathway Hydrogen evolution reaction Acidic water electrolysis

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Busemann–Petty Problems for General L_p-Intersection Bodies

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Acta Mathematica Sinica,English Series 2015年第5期31卷 777-786页

作者： Wei Dong WANG ya nan li Department of Mathematics China Three Gorges University

For 0 〈 p 〈 1, Haberl and Ludwig defined the notions of symmetric Lp-intersection body and nonsymmetric Lp-intersection body. In this paper, we introduce the general Lp-intersection bodies. Furthermore, the Busemann... 详细信息

关键词： General Lp-intersection body Busemann-Petty problem

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