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Analysis of sparteines in the seeds of Ammopiptanthus mongolica

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Frontiers in Biology 2008年第4期3卷 459-462页

作者： wen XIAO Huixian jia Gansu Agricultural University Lanzhou 730070China

Seven alkaloids were isolated from the seeds of Ammopiptanthus mongolica by thin layer chromatography and silica gel column chromatography,and the chemical structures of five alkaloids,17-oxosparteine,b-isosparteine,3a-hydroxysparteine,sparteine,and 3b-hydroxysparteine were identified by 1H nuclear magnetic resonance(NMR)and electron ionization mass spectrum(EIMS).

关键词： Ammopiptanthus mongolicus(Maxim)Cheng f. alkaloids sparteine 1HNMR electron ionization mass spectrum(EIMS)

Research progress in drug therapy of juvenile idiopathic arthritis

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World Journal of Pediatrics 2022年第6期18卷 383-397页

作者： wen-jia Zhao jiang-Hong Deng Cai-Feng Li Department of Rheumatology Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthNo.56Nan Li Shi RoadBeijing100045China

Background Juvenile idiopathic arthritis(jia)is the most common chronic rheumatic disease in *** the gradual expansion of the incidence of jia in the population,the pathogenesis and treatment of jia were further explored and analyzed,and jia has achieved some success in drug *** sources A systemic literature search was conducted on PubMed,Cochrane Library,EMBASE,ISI Web of Science,the US National Institutes of Health Ongoing Trials Register,and the EU Clinical Trials *** the searching of clinical trials of jia in recent years,we summarized the progress of the clinical treatment of *** The main treatment drugs for jia include non-steroidal anti-inflammatory drugs,glucocorticoids,disease-modifying antirheumatic drugs and biological *** far,a variety of biological agents targeting the cytokines and receptors involved in its pathogenesis have been gradually approved for jia in many *** application of biological agents in jia showed good efficacy and safety,bringing unprecedented experience to children and adolescents with *** The potential and advantages of biologic agents in the treatment of jia are significant,and the application of biologic agents in the treatment of jia will be more and more common.

关键词： Juvenile idiopathic arthritis Progress Treatment

Clinical characteristics of COVID-19 in family clusters: a systematic review

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World Journal of Pediatrics 2021年第4期17卷 355-363页

作者： wen-Liang Song Ning Zou wen-He Guan jia-Li Pan Wei Xu Department of Pediatrics Shengjing Hospital of China Medical UniversityNo.36SanHao StreetShenyang110004China

Background Coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has spread around the world and reports of children during early epidemic period showed features of family *** aim of this study is to assess clinical profiles of COVID-19 in family clusters with *** We performed a systematic literature review of English database(PubMed,Web of Science)and Chinese database(“***”,“***”and“***”)to identify papers on family clusters of COVID-19 with children and their family *** Eighteen studies involving 34 children and 98 adults from 28 families were ***,cough and ground-grass opacity change of chest computed tomography(CT)were the dominant features,whereas proportion of asymptomatic infections for children was higher than adults with statistical significance(32.4%and 13.3%,respectively,Pwenty-seven families reported adults as first case of COVID-19 in family *** The same virus strain can cause milder disease in children compared with their *** of COVID-19 were infected by adults in family during the early epidemic *** patients can transmit the virus.

关键词： Children Coronavirus disease 2019 Family clusters Severe acute respiratory syndrome coronavirus 2

Enhancement and selective production of avermectin B by recombinants of Streptomyces avermitilis via intraspecific protoplast fusion

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Chinese Science Bulletin 2007年第5期52卷 616-622页

作者： CHEN Zhi wen jia SONG Yuant wen Ying LI JiLun Department of Microbiology College of Biological Sciences China Agricultural University Beijing 100094 China

Among eight components of avermectin, B1 fractions have the most effective antiparasitic activities and the lowest level of toxic side-effects and are used widely in veterinary and agricultural fields. In-traspecific protoplast fusion between two strains of Streptomyces avermitilis, one an avermectin high producer (strain 76-05) and the other a genetically engineered strain containing the mutations aveDˉ and olmAˉ (strain 73-12) was performed for enhancement and selective production of avermectin B in the absence of oligomycin. Two recombinant strains (F23 and F29) were isolated and characterized with regards to the parental merits. F23 and F29 produced only the four avermectin B components with high yield and produced no oligomycin. The avermectin production of F23 and F29 was about 84.20% and 103.45% of the parental strain 76-05, respectively, and increased about 2.66-fold and 3.50-fold, re-spectively, compared to that of parental strain 73-12. F23 and F29 were genetically stable prototrophic recombinants and F29 was quite tolerant of fermentation conditions compared to avermectin high producer parental strain 76-05. The ability to produce avermectin B with high yield without the produc-tion of other avermectin components and oligomycin will make F23 and F29 useful strains for aver-mectin production. Strain F29's tolerance of fermentation conditions will also make it suitable for in-dustrial applications.

关键词：除虫链霉菌重组体种内原生质体融合除虫菌素B 高产菌株选择性生产阿维菌素B

Effect of Martian atmosphere on aerodynamic performance of supersonic parachute two-body systems

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Chinese Journal of Aeronautics 2022年第4期35卷 45-54页

作者： Xiaopeng XUE He jia Wei RONG Qi WANG Chih-yung wen School of Aeronautics and Astronautics Central South UniversityChangsha 410083China Beijing Institute of Space Mechanics and Electricity Beijing 100094China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong KongChina

Supersonic flows around parachute two-body systems are numerically investigated by solving the compressible Navier-Stokes equations. In the present study, both rigid and flexible parachute models are considered, which comprise a capsule and a canopy. The objective of the present study is to investigate the effects of the Martian atmosphere on the unsteady flows produced by these parachute two-body models and the structural behavior of the flexible canopy. It was found that in the Martian atmosphere, the supersonic rigid parachutes with shorter trailing distances exhibited weaker aerodynamic interactions between the capsule wake and canopy shock, resulting in a smaller pressure distribution on the typical surfaces of the canopy. By contrast, because the flow modes around the flexible parachute in the Martian atmosphere were similar to those of the rigid parachute under the air conditions of the wind tunnel tests, the canopy shape was almost unchanged. When a new canopy material was designed by decreasing the Young’s modulus and damping coefficient, an area oscillation phenomenon was observed in the flexible parachute with a trailing distance of 10 in the Martian atmosphere. Consequently, the Martian atmosphere(low density and pressure) has a significant effect on the aerodynamic performance of the flexible parachute system.

关键词： Canopy flexibility Fluid structure interaction Martian atmosphere Supersonic parachute Unsteady flow

Numerical Study on the Pulsation Characteristics of An Attached Air Bubble Under A Nearby Oscillating Bubble

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China Ocean Engineering 2023年第2期37卷 299-311页

作者： jiaNG Ming-zuo LIU Kun WANG jia-xia wen Xiao-hu College of Automation Jiangsu University of Science and TechnologyZhenjiang 212003China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Numerical simulations of the non-spherical evolution of a pulsating bubble interacting with a stationary air bubble attached to a fixed structure were performed using a three-dimensional boundary integral method by implementing the mirror image method to simplify the processing of the numerical model. Code validation was accomplished by comparing the numerical results with the laboratory experimental data obtained in our previous study. Complex phenomena were observed, including three types of bubble jet forms, which depended strongly on the distance parameter with respect to the initial location of the bubble from the plate, the bubble strength parameter and the initial air bubble radius parameters. The results of the simulations provide detail insight into interesting bubble jetting phenomena,such as bubble splitting, jets moving away from the plate, and bubble shedding. The dimensionless distance parameter and the initial air bubble radius parameter play a major role in determining the shapes of two bubbles and the jetting direction. The air bubble strength parameter did not change the bubble jet direction but influenced the bubble *** detachment of the attached air bubble under oscillating bubble suction was easily observed for a small initial air bubble. These results showed that bubble jetting toward the plate was manipulated through the effect of attached air bubble, and that cavitation-based applications and underwater explosion bubble may benefit from this erosion mitigation approach.

关键词： bubble dynamics attached air bubble bubble collapse liquid jet

Simulation Study on Constraining Gravitational Wave Propagation Speed by Gravitational Wave and Gamma-ray Burst Joint Observation on Binary Neutron Star Mergers

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Research in Astronomy and Astrophysics 2024年第8期24卷 42-51页

作者： Jin-Hui rao Shu-Xu Yi Lian Tao Qing-wen Tang Department of Physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Theories of modified gravity suggest that the propagation speed of gravitational waves(GW)v_gmay deviate from the speed of light c.A constraint can be placed on the difference between c and v_gwith a simple method that uses the arrival time delay between GW and electromagnetic wave simultaneously emitted from a burst *** simulated the joint observation of GW and short gamma-ray burst signals from binary neutron star merger events in different observation campaigns,involving advanced LIGO(aLIGO)in design sensitivity and Einstein Telescope(ET)joint-detected with Fermi/*** a result,the relative precision of constraint on v_gcan reach~10~(-17)(aLIGO)and~10^(-18)(ET),which are one and two orders of magnitude better than that from GW170817,*** continue to obtain the bound of graviton mass m_g≤7.1(3.2)×10~(-20)eV with aLIGO(ET).Applying the Standard-Model Extension test framework,the constraint on v_gallows us to study the Lorentz violation in the nondispersive,nonbirefringent limit of the gravitational *** obtain the constraints of the dimensionless isotropic coefficients S_(00)^(4)at mass dimension d=4,which are-1×10^(-15)

关键词： gravitational waves-(stars)gamma-ray burst general-stars neutron

Viscoplastic constitutive model of a nickel-based superalloy under multiaxial loading conditions

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Journal of Iron and Steel Research International 2021年第9期28卷 1190-1202页

作者： wen-bin jia Xin Li Zhi Chen Kai Zhao Lei Fang Key Laboratory of Aero-Engine Thermal Environment and Structure Ministry of Industry and Information TechnologyJiangsu Province Key Laboratory of Aerospace Power SystemState Key Laboratory of Mechanics and Control of Mechanical StructuresCollege of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing210016JiangsuChina

Based on Chaboche constitutive model,a viscoplastic constitutive model of nickel-based alloy under multiaxial loading is proposed by introducing Lemaitre damage model and non-proportional hardening *** damage model can characterize the effect of microscopic defects on the fatigue behavior and non-proportional hardening factor is used to describe non-proportional hardening ***,the stress–strain hysteresis loops at room and high temperatures under different loading conditions are simulated by the proposed constitutive *** between experiments and simulations confirms that the proposed model can reasonably predict the fatigue behavior of nickel-based alloy under different multiaxial *** last,the fatigue life predictions under different multiaxial loadings are investigated,and comparison between experiments and simulations verifies the accuracy of the proposed model.

关键词： Nickel-based alloy Multiaxial loading Viscoplastic constitutive model Lemaitre damage model Non-proportional hardening factor

Optical biometry intraocular lens power calculation using different formulas in patients with different axial lengths

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International Journal of Ophthalmology(English edition) 2013年第2期6卷 150-154页

作者： jia-Kang Wang Shu-wen Chang Department of Ophthalmology Far Eastern Memorial Hospital Oriental Institute of Technology Department of Medicine National Yang Ming University

AIM: To investigate the predictability of intraocular lens (IOL) power calculation using the IOLMaster and different IOL power calculation formulas in eyes with various axial length (AL). METHODS: Patients were included who underwent uneventful phacoemulsification with IOL implantation in the Department of Ophthalmology, Far Eastern Memorial Hospital, Taipei, Taiwan, China from February 2007 to January 2009. Preoperative AL and keratometric values (Ks) were measured by IOLMaster optical biometry. Patients were divided into 3 groups based on AL less than 22mm (Group 1), 22-26mm (Group 2), and more than 26mm (Group 3). The power of the implanted IOL was used to calculate the predicted postoperative spherical equivalence (SE) by various formulas: the Haigis, Hoffer Q, Holladay 1, and SRK/T. The predictive accuracy of each formula was analyzed by comparing the difference between the actual and predicted postoperative SE (MedAE, median absolute error). All the patients had follow-up periods exceeding 3 months. RESULTS: Totally, there were 200 eyes (33 eyes in Group 1, 92 eyes in Group 2, 75 eyes in Group 3). In all patients, the Haigis had the significantly lower MedAE generated by the other formulas (P<0.05). In Group 1 to 3, the MedAE calculated by the Haigis was either significantly lower or comparable to those calculated by the other ***: Compared with other formulas using IOLMaster biometric data, the Haigis formula yields superior refractive results in eyes with various AL.

关键词： intraocular lens optical biometry calculation formula