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Effects of cold narcosis on memory acquisition, consolidation and retrieval in honeybees (Apis mellifera) 被引量:1
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作者 yan-mei chen Yu FU +1 位作者 Jing HE Jian-Hong WANG 《Zoological Research》 CAS CSCD 北大核心 2014年第2期118-123,共6页
In learning and memory studies on honeybees (Apis mellifera), cold-induced narcosis has been widely used to temporarily immobilize honeybees. In this study, we investigated the effects of cold narcosis on the associ... In learning and memory studies on honeybees (Apis mellifera), cold-induced narcosis has been widely used to temporarily immobilize honeybees. In this study, we investigated the effects of cold narcosis on the associative memories in honeybees by using the proboscis extension response (PER) paradigm. Severe impairments in memory acquisition was found when cold narcosis was performed 30 rain, instead of 1 h before training. Locomotor activities were reduced when honeybees were tested 15 min, instead of 30 rain after cold narcosis. These results indicate that cold narcosis impairs locomotor activities, as well as memory acquisition in a time-dependent manner, but by comparison no such effects on memory retrieval have yet been observed.[0] 展开更多
关键词 HONEYBEE Cold narcosis Associative learning Memory
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Radio Luminosity,Black Hole Mass and Eddington Ratio for Quasars from the Sloan Digital Sky Survey 被引量:1
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作者 Wei-Hao Bian yan-mei chen +2 位作者 chen Hu Kai Huang Yan Xu 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第5期522-536,共15页
We investigate the MBH-σ* relation for radio-loud quasars with redshifl z 〈 0.83 in Data Release 3 of the Sloan Digital Sky Survey (SDSS). The sample consists of 3772 quasars with better models of the H/4 and [O ... We investigate the MBH-σ* relation for radio-loud quasars with redshifl z 〈 0.83 in Data Release 3 of the Sloan Digital Sky Survey (SDSS). The sample consists of 3772 quasars with better models of the H/4 and [O Ⅲ] lines and available radio luminosity, including 306 radio-loud quasars, 3466 radio-quiet quasars with measured radio luminosity or upper-limit of radio luminosity (181 radio-quiet quasars with measured radio luminosity). The virial supermassive black hole mass (MBH) is calculated from the broad Hβline, and the host stellar velocity dispersion (σ*) is traced by the core [O Ⅲ] gaseous velocity dispersion. The radio luminosity and radio loudness are derived from the FIRST catalog. Our results are as follows: (1) For radio-quiet quasars, we confirm that there is no obvious deviation from the MBH-σ* relation defined for inactive galaxies when the uncertainties in ~IBH and the luminosity bias are concerned. (2) We find that the radio-loud quasars deviate more from the MBH-σ* relation than do the radio-quiet quasars. This deviation is only partly due to a possible cosmological evolution of the MBH-σ* relation and the luminosity bias. (3) The radio luminosity is proportional to MBH1.28+0.23-0.16(LBol/LEdd) ^1.29+0.31-0.24 for radio-quiet quasars and to -MBH3.10+0.60-0.70(LBol/LEdd)^4.18+1.40-1.10 - for radio-loud quasars. The weaker dependence of the radio luminosity on the mass and the Eddington ratio for radio-loud quasars shows that other physical effects would account for their radio luminosities, such as the spin of the black hole. 展开更多
关键词 QUASARS emission lines - galaxies nuclei -galaxies bulges - black hole physics
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Spatially resolved properties of supernova host galaxies in SDSS-IV MaNGA
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作者 Hong-Xuan Zhang yan-mei chen +2 位作者 Yong Shi Min Bao Xiao-Ling Yu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第12期383-395,共13页
We crossmatch galaxies from Mapping Nearby Galaxies at Apache Point Observatory with the Open Supernova Catalog,obtaining a total of 132 SNe within MaNGA bundle.These 132 SNe can be classified into 67 Type Ia and 65 T... We crossmatch galaxies from Mapping Nearby Galaxies at Apache Point Observatory with the Open Supernova Catalog,obtaining a total of 132 SNe within MaNGA bundle.These 132 SNe can be classified into 67 Type Ia and 65 Type CC.We study the global and local properties of supernova host galaxies statistically.Type Ia SNe are distributed in both star-forming galaxies and quiescent galaxies,while Type CC SNe are all distributed along the star-forming main sequence.As the stellar mass increases,the Type Ia/CC number ratio increases.We find:(1)there is no obvious difference in the interaction possibilities and environments between Type Ia SN hosts and a control sample of galaxies with similar stellar mass and SFR distributions,except that Type Ia SNe tend to appear in galaxies which are more bulge-dominated than their controls.For Type CC SNe,there is no difference between their hosts and the control galaxies in galaxy morphology,interaction possibilities as well as environments;(2)compared to galaxy centers,the SN locations have smaller velocity dispersion,lower metallicity,and younger stellar population.This is a natural result of radius gradients for all these parameters.The SN location and its symmetrical position relative to the galaxy center,as well as regions with similar effective radii have very similar[Mg/Fe],gasphase metallicity,gas velocity dispersion and stellar population age. 展开更多
关键词 galaxies:general galaxies:abundances supernovae:general techniques:spectroscopic
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The morphology, kinematics and metallicity of blue-core galaxies
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作者 Yong-Yun chen yan-mei chen +3 位作者 Qiu-Sheng Gu Yong Shi Long-Ji Bing Xiao-Ling Yu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第6期51-62,共12页
We select 107 blue-core galaxies from the MaNGA survey, studying their morphology, kinematics as well as the gas-phase metallicity. Our results are as follows:(i) In our sample, 26% of blue-core galaxies have decouple... We select 107 blue-core galaxies from the MaNGA survey, studying their morphology, kinematics as well as the gas-phase metallicity. Our results are as follows:(i) In our sample, 26% of blue-core galaxies have decoupled gas-star kinematics, indicating external gas accretion;15% have bar-like structure and 8% show post-merger features, such as tidal tails and irregular gas/star velocity field. All these processes/features, such as accreting external misaligned gas, interaction and bar, can trigger gas inflow. Thus the central star-forming activities lead to bluer colors in their centers(blue-core galaxies).(ii) By comparing with the SDSS DR7 star-forming galaxy sample, we find that the blue-core galaxies have higher central gas-phase metallicity than what is predicted by the local mass-metallicity relation. We explore the origin of the higher metallicity, finding that not only the blue-core galaxies, but also the flat-gradient and red-core galaxies all have higher metallicity. This can be explained by the combined effect of redshift and galaxy color. 展开更多
关键词 GALAXIES abundances-galaxies formation-galaxies structure
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Quasar SDSS J142507.32+323137.4: dual AGNs?
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作者 Zhi-Xin Peng yan-mei chen +1 位作者 Qiu-Sheng Gu chen Hu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第4期411-418,共8页
We analyze the optical spectrum of type 1 QSO SDSS J1425+3231. This object is interesting since its narrow emission lines, such as [O Ⅲ]λλ4959, 5007, are double-peaked, and the line structure can be modeled well b... We analyze the optical spectrum of type 1 QSO SDSS J1425+3231. This object is interesting since its narrow emission lines, such as [O Ⅲ]λλ4959, 5007, are double-peaked, and the line structure can be modeled well by three Gaussian components: two components for the two peaks (we refer to the peaks at low/high redshift as "the blue/red component") and another one for the line wing which has the same line center as that of the blue component, but is- 3 times broader. The separation between the blue and red components is -500km s-1 with the blue component being -2 times broader than the red one. The Hβ emission can be separated into four components: two for the double-peaked narrow line and two for the broad line which comes from the broad line regions. The black hole mass estimated from the broad Hβ emission line using the typical reverberation mapping relation is 0.85 × 108 M⊙, which is consistent with that derived from parameters of [O Ⅲ]λ 5007 of the blue component. We suggest that this QSO might be a dual AGN system; the broad Hβ emission line is mainly contributed by the primary black hole (traced by the blue component) while the broad Hβ component of the secondary black hole (traced by the red component) is hard to be separated out considering a resolution of - 2 000 for SDSS spectra or it may be totally obscured by the dusty torus. 展开更多
关键词 galaxie active -- galaxies individual (SDSS J142507.32+323137.4)-- quasars emission lines
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Glycated albumin as a biomarker for diagnosis of diabetes mellitus:A systematic review and meta-analysis
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作者 Jia-Yao Xiong Jun-Mei Wang +5 位作者 Xiao-Lan Zhao Chao Yang Xian-Shu Jiang yan-mei chen Chang-Qin chen Zhi-Yong Li 《World Journal of Clinical Cases》 SCIE 2021年第31期9520-9534,共15页
BACKGROUND Glycated albumin(GA),the non-enzymatic glycation product of albumin in plasma,became a glycemic marker in the beginning of the 21st century.The assay is not affected by hemoglobin levels and reflects the gl... BACKGROUND Glycated albumin(GA),the non-enzymatic glycation product of albumin in plasma,became a glycemic marker in the beginning of the 21st century.The assay is not affected by hemoglobin levels and reflects the glycemic status over a shorter period as compared to HbA1c measurements.Thus,GA may contributes as an intermediate glucose index in the current diabetes mellitus(DM)diagnostic system.AIM To search and summarize the available data on glycated albumin measurements required for the diagnosis of diabetes mellitus.METHODS Databases,including PubMed,Embase,Web of Science,and Cochrane Central Register of Controlled Trials(CENTRAL),among others,were systematically searched.The Quality Assessment of Diagnostic Accuracy Studies-2 tool was applied for the assessment of quality,and the bivariate model was used to pool the sensitivity and specificity.The hierarchical summary receiver operator characteristic curves(HSROC)model was utilized to estimate the summary receiver operating characteristics curve(SROC).Sensitivity analysis was performed to investigate the association of the study design and patient characteristics with the test accuracy and meta-regression to find the source of heterogeneity.RESULTS Three studies regarding gestational diabetes mellitus(GDM)and a meta-analysis of 16 non-GDM studies,comprising a total sample size of 12876,were included in the work.Results reveal that the average cut-off values of GA reported for the diagnosis of GDM diagnosis was much lower than those for non-GDM.For non-GDM cases,diagnosing DM with a circulating GA cut-off of 14.0%had a sensitivity of 0.766(95%CI:0.539,0.901),specificity of 0.687(95%CI:0.364,0.894),and area under the curve of 0.80(95%CI:0.76,0.83)for the SROC.The estimated SROC at different GA cut-off values for non-GDM exhibited that the average location parameter lambda of 16 non-GDM studies was 2.354(95%CI:2.002,2.707),and the scale parameter beta was-0.163(95%CI:-0.614,0.288).These non-GDM studies with various thresholds had substantial heterogeneity,which may be attributed to the type of DM,age,and body mass index as possible sources.CONCLUSION Glycated albumin in non-DM exhibits a moderate diagnostic accuracy.Further research on the diagnostic accuracy of GA for GDM and combinational measurements of GA and other assays is suggested. 展开更多
关键词 Glycated albumin Diabetes mellitus DIAGNOSIS Sensitivity and Specificity Systematic review META-ANALYSIS
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Disk-Corona Model in Active Galactic Nuclei: an Observational Test
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作者 Fang Yang chen Hu +1 位作者 yan-mei chen Jian-Min Wang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2007年第3期353-363,共11页
We compiled a sample of 98 radio-quiet active galactic nuclei observed by ASCA, Chandra, XMM-Newton, INTEGRAL and Swift with the aim of testing the formation of hot corona and the magnetic shear stress operating in a ... We compiled a sample of 98 radio-quiet active galactic nuclei observed by ASCA, Chandra, XMM-Newton, INTEGRAL and Swift with the aim of testing the formation of hot corona and the magnetic shear stress operating in a disk-corona system. We found a strong correlation between the hard X-ray luminosity, bolometric luminosity LBol and Eddington luminosity LEdd, in the sense that the fraction f of hard X-ray to the bolometric luminosity is inversely proportional to the Eddington ratio. This correlation favors the shear stress tensor being of the form of trФ∝ Pgas, with which the disk-corona structure is stable. 展开更多
关键词 accretion accretion disks - galaxies active - magnetic fields
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The broad wing of the [O Ⅲ] λ5007 emission line in active galactic nuclei
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作者 Zhi-Xin Peng yan-mei chen +1 位作者 Qiu-Sheng Gu Kai Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第8期913-922,共10页
We use a sample of type 2 active galactic nuclei (AGNs) from SDSS DR7 in which the [O Ⅲ] )λ5007 emission line can be modeled by two Gaussian components, a broad wing plus a narrow core, to investigate the origin ... We use a sample of type 2 active galactic nuclei (AGNs) from SDSS DR7 in which the [O Ⅲ] )λ5007 emission line can be modeled by two Gaussian components, a broad wing plus a narrow core, to investigate the origin of the broad wing and the connection between the velocity shift of the broad wing and the physical parameters of AGNs, as well as their host galaxies. We find that the flux of the wing components is statistically roughly equal to that of the core components. However, the velocity shift of the wing component has only weak, if any, correlations with the physical properties of AGNs and the host galaxies, such as bolometric luminosity, the Eddington ratio, the mass of supermassive black holes, D4000, H3A or stellar mass. Comparing the velocity shift from our type 2 AGN sample to that from the type 1 sample in Zhang et al., we suggest that the [O Ⅲ]] broad wing originates from outflow. 展开更多
关键词 galaxies: active -- galaxies: Seyfert -- quasars: emission lines
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Identifying the Risk of SARS-CoV-2 Infection and Environmental Monitoring in Airborne Infectious Isolation Rooms(AIIRs) 被引量:3
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作者 Zhi-Gang Song yan-mei chen +10 位作者 Fan Wu Lin Xu Bang-Fang Wang Lei Shi Xiao chen Fa-Hui Dai Jia-Lei She Jian-Min chen Edward CHolmes Tong-Yu Zhu Yong-Zhen Zhang 《Virologica Sinica》 SCIE CAS CSCD 2020年第6期785-792,共8页
Healthcare workers(HCWs)are at high risk of occupational exposure to the new pandemic human coronavirus,SARSCoV-2,and are a source of nosocomial transmission in airborne infectious isolation rooms(AIIRs).Here,we perfo... Healthcare workers(HCWs)are at high risk of occupational exposure to the new pandemic human coronavirus,SARSCoV-2,and are a source of nosocomial transmission in airborne infectious isolation rooms(AIIRs).Here,we performed comprehensive environmental contamination surveillance to evaluate the risk of viral transmission in AIIRs with 115 rooms in three buildings at the Shanghai Public Health Clinical Center,Shanghai,during the treatment of 334 patients infected with SARS-CoV-2.The results showed that the risk of airborne transmission of SARS-CoV-2 in AIIRs was low(1.62%,25/1544)due to the directional airflow and strong environmental hygiene procedures.However,we detected viral RNA on the surface of foot-operated openers and bathroom sinks in AIIRs(viral load:55.00–3154.50 copies/mL).This might be a source of contamination to connecting corridors and object surfaces through the footwear and gloves used by HCWs.The risk of infection was eliminated by the use of disposable footwear covers and the application of more effective environmental and personal hygiene measures.With the help of effective infection control procedures,none of 290 HCWs was infected when working in the AIIRs at this hospital.This study has provided information pertinent for infection control in AIIRs during the treatment of COVID-19 patients. 展开更多
关键词 SARS-CoV-2 COVID-19 Nosocomial transmission AIIRs Environmental sampling
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Mass Loss and Direct Reduction Characteristics of Iron Ore-coal Composite Pellets 被引量:2
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作者 Yi MAN Jun-xiao FENG +1 位作者 yan-mei chen Jing-zhi ZHOU 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 2014年第12期1090-1094,共5页
Mass loss and direct reduction characteristics of iron ore-coal composite pellets under different technological parameters were investigated. Meanwhile, changes of iron phase at different temperatures were analyzed by... Mass loss and direct reduction characteristics of iron ore-coal composite pellets under different technological parameters were investigated. Meanwhile, changes of iron phase at different temperatures were analyzed by using X-ray diffraction (XRD), and characteristics of crushed products were studied by using a scanning electron microscope (SEM). The results showed that heating rate had little influence on the reduction, but the temperature played an important role in the reduction process. The mass loss rate increased rapidly from 800 to 1 100 ℃. The reduction process can be divided into three steps which correspond to different temperature ranges. Fe2 03 began to transform into Fe304 below 500 ℃, and FeO was reduced into Fe from 900 ℃. At 900 ℃, the reduction product showed a clear porous structure, which promoted the reduction progress. At 1000 ℃, the metallic Fe dominated the sample, and the reduction reached a very high degree. 展开更多
关键词 iron ore coal composite pellet direct reduction mass loss reduction characteristics
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Interactive effects of morphine and dopaminergic compounds on spatial working memory in rhesus monkeys
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作者 Jian-Hong Wang Joshua Dominie Rizak +3 位作者 yan-mei chen Liang Li Xin-Tian Hu Yuan-Ye Ma 《Neuroscience Bulletin》 SCIE CAS CSCD 2013年第1期37-46,共10页
Opiates and dopamine (DA) play key roles in learning and memory in humans and animals. Although interactions between these neurotransmitters have been found, their functional roles remain to be fully elucidated, and... Opiates and dopamine (DA) play key roles in learning and memory in humans and animals. Although interactions between these neurotransmitters have been found, their functional roles remain to be fully elucidated, and their dysfunction may contribute to human diseases and addiction. Here we investigated the interactions of morphine and dopaminergic neurotransmitter systems with respect to learning and memory in rhesus monkeys by using the Wisconsin General Test Apparatus (WGTA) delayed-response task. Morphine and DA agonists (SKF-38393, apomorphine and bromocriptine) or DA antagonists (SKF-83566, haloperidol and sulpiride) were co-administered to the monkeys 30 min prior to the task. We found that dose-patterned co-administration of morphine with D1 or D2 antagonists or agonists reversed the impaired spatial working memory induced by morphine or the compounds alone. For example, morphine at 0.01 mg/kg impaired spatial working memory, while morphine (0.01 mg/kg) and apomorphine (0.01 or 0.06 mg/kg) co-treatment ameliorated this effect. Our findings suggest that the interactions between morphine and dopaminergic compounds influence spatial working memory in rhesus monkeys. A better understanding of these interactive relationships may provide insights into human addiction. 展开更多
关键词 working memory MORPHINE DOPAMINE rhesus monkey
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