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改良BLUE方案肺超声评分在机械通气患者中的应用价值
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作者 秦桂香 储鑫 +2 位作者 吕学东 朱保锋 陈建荣 《生物医学工程与临床》 CAS 2024年第3期348-353,共6页
目的比较改良BLUE方案肺超声评分与传统区域评分法在机械通气患者中的应用优劣,探讨改良BLUE方案与序贯器官衰竭评估(SOFA)评分、氧合指数(OI)的相关性及其对机械通气患者预后评估的价值。方法选择南通大学第二附属医院急诊医学科行机... 目的比较改良BLUE方案肺超声评分与传统区域评分法在机械通气患者中的应用优劣,探讨改良BLUE方案与序贯器官衰竭评估(SOFA)评分、氧合指数(OI)的相关性及其对机械通气患者预后评估的价值。方法选择南通大学第二附属医院急诊医学科行机械通气的危重症患者66例,其中男性45例,女性21例;年龄35~95岁,平均年龄72.11岁;病程2~37 d,平均病程12.03 d;疾病类型:肺炎、感染性休克等感染相关19例,心力衰竭16例,慢性阻塞性肺疾病急性发作呼吸衰竭15例,心肺复苏后11例,间质性肺炎2例,中毒2例,外伤1例。根据患者的转归情况(28 d生存或死亡)分为好转组28例与死亡组38例。分别使用改良BLUE方案、4分区、6分区、8分区及12分区评分方法对患者进行肺部超声检查,以12分区评分为对照,分别比较改良BLUE方案、4分区、6分区、8分区超声评分与12分区评分结果的相关性。记录各检查方案检查时间,比较各评分法耗时差异。分析改良BLUE方案与SOFA评分和OI的相关性。比较两组改良BLUE方案肺超声评分差异。结果在机械通气患者中,改良BLUE方案、4分区、6分区、8分区超声评分结果,均与12分区法评分结果呈正相关(r=0.98、0.94、0.96、0.95,P均<0.05),其中改良BLUE方案肺超声评分与12分区评分相关性最高。改良BLUE方案、4分区、6分区、8分区及12分区肺超声检查操作时间分别为(5.86±0.76)min、(4.86±0.71)min、(6.79±0.88)min、(8.18±1.02)min、(11.79±1.45)min,改良BLUE方案较6分区、8分区及12分区操作时间短(P均<0.05)。改良BLUE方案肺超声评分与OI呈负相关,与SOFA评分呈正相关(r=-0.42、0.25)。好转组与死亡组改良BLUE方案肺超声评分平均值分别为(12.04±5.87)分、(15.79±5.94)分。好转组改良BLUE方案肺超声评分明显低于死亡组,差异有统计学意义(P<0.05)。结论在机械通气危重症患者中,使用改良BLUE方案肺超声评分具有准确度高、耗时短的优势,更适宜在急诊环境中对机械通气危重症患者进行快速病情评估。改良BLUE方案肺超声评分对机械通气患者病情严重程度及预后有一定指导价值。 展开更多
关键词 肺超声 肺超声评分 改良blue方案 机械通气
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BLUE-plus方案的肺超声评分在急性呼吸衰竭患者胸部物理治疗中的应用
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作者 陈春艳 张艳阳 王柱 《湖北理工学院学报》 2024年第5期63-68,共6页
为了探究BLUE-plus方案的肺超声评分引导胸部物理治疗(CPT)在急性呼吸衰竭患者氧合能力、感染指标和肺通气功能方面的效果,根据样本量估算招募急性呼吸衰竭患者102例,随机分为试验组和对照组。试验组根据BLUE-plus肺超声征象、肺超声评... 为了探究BLUE-plus方案的肺超声评分引导胸部物理治疗(CPT)在急性呼吸衰竭患者氧合能力、感染指标和肺通气功能方面的效果,根据样本量估算招募急性呼吸衰竭患者102例,随机分为试验组和对照组。试验组根据BLUE-plus肺超声征象、肺超声评分实施精准CPT,对照组采用常规CPT。比较两组患者入ICU第1~5天的氧合指数和第1、5天的血感染指标(降钙素原(PCT)、白介素-6(IL-6))及肺部超声评分、机械通气时长和ICU住院时长,发现BLUE-plus方案的肺超声评分指导的CPT可以改善急性呼吸衰竭患者的氧合指数、感染指标(IL-6)、肺部情况,缩短机械通气的时间。相较于对照组,试验组在第3~5天的氧合指数具有统计学差异(P<0.05),第5天IL-6、肺部超声评分、机械通气时长差异具有统计学意义(P<0.05),PCT、ICU住院时长无统计学差异(P>0.05)。 展开更多
关键词 blue-plus肺超声引导 急性呼吸衰竭 胸部物理治疗 氧合指数 肺超声评分
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Apatinib and gamabufotalin co-loaded lipid/Prussian blue nanoparticles for synergistic therapy to gastric cancer with metastasis 被引量:1
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作者 Binlong Chen Yanzhong Zhao +5 位作者 Zichang Lin Jiahao Liang Jialong Fan Yanyan Huang Leye He Bin Liu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第5期707-721,共15页
Due to the non-targeted release and low solubility of anti-gastric cancer agent,apatinib(Apa),a first-line drug with long-term usage in a high dosage often induces multi-drug resistance and causes serious side effects... Due to the non-targeted release and low solubility of anti-gastric cancer agent,apatinib(Apa),a first-line drug with long-term usage in a high dosage often induces multi-drug resistance and causes serious side effects.In order to avoid these drawbacks,lipid-film-coated Prussian blue nanoparticles(PB NPs)with hyaluronan(HA)modification was used for Apa loading to improve its solubility and targeting ability.Furthermore,anti-tumor compound of gamabufotalin(CS-6)was selected as a partner of Apawith reducing dosage for combinational gastric therapy.Thus,HA-Apa-Lip@PB-CS-6 NPs were constructed to synchronously transport the two drugs into tumor tissue.In vitro assay indicated that HA-Apa-Lip@PB-CS-6 NPs can synergistically inhibit proliferation and invasion/metastasis of BGC-823 cells via downregulating vascular endothelial growth factor receptor(VEGFR)and matrix metalloproteinase-9(MMP-9).In vivo assay demonstrated strongest anti-tumor growth and liver metastasis of HA-Apa-Lip@PB-CS-6 NPs administration in BGC-823 cells-bearing mice compared with other groups due to the excellent penetration in tumor tissues and outstanding synergistic effects.In summary,we have successfully developed a new nanocomplexes for synchronous Apa/CS-6 delivery and synergistic gastric cancer(GC)therapy. 展开更多
关键词 Apatinib Gamabufotalin Lipid/Prussian blue nanoparticles Gastric cancer
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Progress on Transition Metal Ions Dissolution Suppression Strategies in Prussian Blue Analogs for Aqueous Sodium-/Potassium-Ion Batteries 被引量:1
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作者 Wenli Shu Junxian Li +3 位作者 Guangwan Zhang Jiashen Meng Xuanpeng Wang Liqiang Mai 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期142-168,共27页
Aqueous sodium-ion batteries(ASIBs)and aqueous potassium-ion batteries(APIBs)present significant potential for large-scale energy storage due to their cost-effectiveness,safety,and environmental compatibility.Nonethel... Aqueous sodium-ion batteries(ASIBs)and aqueous potassium-ion batteries(APIBs)present significant potential for large-scale energy storage due to their cost-effectiveness,safety,and environmental compatibility.Nonetheless,the intricate energy storage mechanisms in aqueous electrolytes place stringent require-ments on the host materials.Prussian blue analogs(PBAs),with their open three-dimensional framework and facile synthesis,stand out as leading candidates for aqueous energy storage.However,PBAs possess a swift capacity fade and limited cycle longevity,for their structural integrity is compromised by the pronounced dis-solution of transition metal(TM)ions in the aqueous milieu.This manuscript provides an exhaustive review of the recent advancements concerning PBAs in ASIBs and APIBs.The dissolution mechanisms of TM ions in PBAs,informed by their structural attributes and redox processes,are thoroughly examined.Moreover,this study delves into innovative design tactics to alleviate the dissolution issue of TM ions.In conclusion,the paper consolidates various strategies for suppressing the dissolution of TM ions in PBAs and posits avenues for prospective exploration of high-safety aqueous sodium-/potassium-ion batteries. 展开更多
关键词 Prussian blue analogs Transition metal ions dissolution Suppression strategies Aqueous sodium-ion batteries Aqueous potassium-ion batteries
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Four Late-type Galaxies with Double Radio Lobes and Properties of Such Galaxies
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作者 Z.S.Yuan X.Y.Gao +1 位作者 Z.L.Wen J.L.Han 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期84-90,共7页
The triggering mechanism for radio lobes from late-type galaxies is not fully understood.More samples are desired for a thorough investigation and statistics.By utilizing the optical data from the newly released Dark ... The triggering mechanism for radio lobes from late-type galaxies is not fully understood.More samples are desired for a thorough investigation and statistics.By utilizing the optical data from the newly released Dark Energy Spectroscopic Instrument imaging surveys and the radio sources from the NRAO VLA Sky Survey and the Faint Images of the Radio Sky at Twenty-centimeter,we identify four Late-type Galaxies with double Radio Lobes(La GRLs):J0217-3645,J0947+6220,J1412+3723 and J1736+5108.Including previously known La GRLs,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host galaxies.Most(25/35)La GRLs belong to the blue cloud galaxies,while the newly identified cases in this work are located within the region of the red sequence.We find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio lobes.Furthermore,the majority(31/36)of La GRLs are either located in a galaxy group or displaying a disturbed morphology.We suggest that all of the galaxy mass,color and surrounding environment could play important roles in triggering radio lobes in late-type galaxies. 展开更多
关键词 galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies
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Stellar Populations of AGN-host Dwarf Galaxies Selected with Different Methods
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作者 Xiejin Li 赵应和 Jinming Bai 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期52-67,共16页
In this paper we investigate the stellar populations and star formation histories of 235 active galactic nucleus(AGN)-host dwarf galaxies,consisting of four samples identified separately with different methods(i.e.,ra... In this paper we investigate the stellar populations and star formation histories of 235 active galactic nucleus(AGN)-host dwarf galaxies,consisting of four samples identified separately with different methods(i.e.,radio,X-ray,mid-IR and variability),utilizing the synthesis code STARLIGHT and spectra from the Sloan Digital Sky Survey Data Release 8.Our results show that the variability sample is the oldest,while the mid-IR sample is the youngest,for which the luminosity at 4020?is dominated(>50%)by the young population(t<10~8yr).The light-weighted mean stellar age of the whole sample is in general about 0.7 dex younger than the optical sample studied in Cai et al.We compare the population results between fitting models with and without a power-law(PL)component and find that the neglect of a PL component would lead to an under-and over-estimation by 0.2 and0.1 dex for the light-and mass-weighted mean stellar age,respectively,for our sample of dwarf galaxies,which has a mean fractional contribution of~16%from the AGN.In addition,we obtain further evidence for a possible suppression of star formation in the host galaxy by the central AGN.We also find that there exists an anticorrelation between the extinction-corrected[O III]luminosity and light-weighted mean stellar age,confirming our previous finding that there is a physical connection between AGN and star-forming activities in AGN-host dwarfs. 展开更多
关键词 galaxies:dwarf galaxies:active galaxies:stellar content
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Morphological Classification of Infrared Galaxies Based on WISE
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作者 Zhi-Ren Pan Bo Qiu +3 位作者 Cui-Xiang Liu A-Li Luo Xia Jiang Xiao-Yu Guo 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期222-236,共15页
This study introduces a novel convolutional neural network,the WISE Galaxy Classification Network(WGC),for classifying spiral and elliptical galaxies using Wide-field Infrared Survey Explorer(WISE)images.WGC attains a... This study introduces a novel convolutional neural network,the WISE Galaxy Classification Network(WGC),for classifying spiral and elliptical galaxies using Wide-field Infrared Survey Explorer(WISE)images.WGC attains an accuracy of 89.03%,surpassing the combined use of K-means or SVM with the Color-Color method in more accurately identifying galaxy morphologies.The enhanced variant,WGC_mag,integrates magnitude parameters with image features,further boosting the accuracy to 89.89%.The research also delves into the criteria for galaxy classification,discovering that WGC primarily categorizes dust-rich images as elliptical galaxies,corresponding to their lower star formation rates,and classifies less dusty images as spiral galaxies.The paper explores the consistency and complementarity of WISE infrared images with SDSS optical images in galaxy morphology classification.The SDSS Galaxy Classification Network(SGC),trained on SDSS images,achieved an accuracy of 94.64%.The accuracy reached 99.30% when predictions from SGC and WGC were consistent.Leveraging the complementarity of features in WISE and SDSS images,a novel variant of a classifier,namely the Multi-band Galaxy Morphology Integrated Classifier,has been developed.This classifier elevates the overall prediction accuracy to 95.39%.Lastly,the versatility of WGC was validated in other data sets.On the HyperLEDA data set,the distinction between elliptical galaxies and Sc,Scd and Sd spiral galaxies was most pronounced,achieving an accuracy of 90%,surpassing the classification results of the Galaxy Zoo 2 labeled WISE data set.This research not only demonstrates the effectiveness of WISE images in galaxy morphology classification but also represents an attempt to integrate multi-band astronomical data to enhance understanding of galaxy structures and evolution. 展开更多
关键词 methods:data analysis infrared:galaxies galaxies:spiral galaxies:elliptical and lenticular CD
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Observation of HⅠaround three Satellite Galaxies of M31 with FAST:AndromedaⅡ,NGC 205,and NGC 185
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作者 Ziming Liu Jie Wang +6 位作者 Yingjie Jing Chen Xu Tiantian Liang Qingze Chen Zerui Liu Zhipeng Hou Yougang Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第8期52-59,共8页
With the exceptional sensitivity of the Five-hundred-meter Aperture Spherical radio Telescope,we conducted observations of the neutral hydrogen(HⅠ)in the circumgalactic medium of Andromeda’s(M31)satellite galaxies,s... With the exceptional sensitivity of the Five-hundred-meter Aperture Spherical radio Telescope,we conducted observations of the neutral hydrogen(HⅠ)in the circumgalactic medium of Andromeda’s(M31)satellite galaxies,specifically AndromedaⅡ,NGC 205,and NGC 185.Initially,three drift scans were executed for these satellites,with a detection limit of 4×10^(18)cm^(-2)(approximately 1.88×10^(3)M_Θof HⅠmass),followed by a more in-depth scan of a specific region.We discovered a C-shaped HⅠarc structure sharing a position and line-of-sight velocity similar to a stellar ring structure around AndromedaⅡ,hinting at a potential connection with AndromedaⅡ.In the context of NGC 205,we identified two mass concentrations in the northeast direction,which could be indicative of tidal streams resulting from the interaction between this galaxy and M31.These new lumps discovered could be very helpful in solving the missing interstellar medium problem for NGC 205.Observations regarding NGC 185are consistent with previous studies,and we did not detect any additional HⅠmaterial around this galaxy.These observational results enhance our understanding of the evolution of these satellite galaxies and provide insight into their historical interactions with the galaxy M31. 展开更多
关键词 ISM structure-(Galaxy)local interstellar matter-galaxies interactions-galaxies ISM-(galaxies)Local Group-radio lines ISM-radio lines galaxies
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A Dark Matter Theory by Quantum Gravitation for Galaxies and Clusters
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作者 Manuel Abarca 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1749-1784,共36页
This paper develops an original theory of dark matter in the current ΛCDM framework, whose main hypothesis is that DM is generated by the own gravitational field, according to an unknown quantum gravitational phenome... This paper develops an original theory of dark matter in the current ΛCDM framework, whose main hypothesis is that DM is generated by the own gravitational field, according to an unknown quantum gravitational phenomenon. This work is the best version of the theory, which I have been developing and publishing since 2014. The hypothesis of DM by quantum gravitation, DMbQG hereafter, has two main consequences: the first one is that the law of DM generation has to be the same, in the halo region, for all the galaxies and the second one is that the haloes are unbounded, so the total DM goes up without limit as the gravitational field is unbounded as well. The first one consequence is backed by the fact that M31 and MW has a fitted function with the same power exponent for the rotation curve at the halo region and both giant galaxies are the only ones whose rotation curves at the halo region may be studied with accuracy. This paper is firstly developed all the theory with M31 rotation curve data up to Chapter 9. The most important formula of the theory is the called Direct mass, which calculates the total mass at a specific radius into the halo region. Chapter 10 is dedicated to apply the theory to Milky Way, it is calculated its total mass at different radius into the halo and such results have been validated successfully using the data of masses at different radius published by two researcher teams. In Chapter 11, it is calculated the direct mass for the Local Group, and it is shown how the DMbQG theory is able to calculate the total mass at 770 kpc, that the dynamical methods estimate to be 5×1012MΘ. In Chapter 12, it is shown a method to estimate the Direct mass formula for a cluster of galaxies, using only its virial mass and virial radius. By this method, it is estimated the parameter a2 of the Local Group, which match with the one calculated in previous chapter by a different method. Also are calculated the parameters a2 associated to Virgo and Coma clusters. In Chapter 13, it is demonstrated how the DE is able to counterbalance the DM at cluster scale, as the Direct mass grows up with the square root of radius whereas the DE grows up with the cubic power. The chapter is an introduction to the DMbQG theory for cluster of galaxies, which has been developed fully by the author in other works. This theory aims to be a powerful method to study DM in the halo region of galaxies and cluster of galaxies and conversely the measures in galaxies and clusters offer the possibility to validate the theory. 展开更多
关键词 Dark Matter Dark Energy galaxies Local Group of galaxies CLUSTERS
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Low Surface Brightness Galaxies Selected by Different Model Fitting
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作者 Bing-Qing Zhang Hong Wu +3 位作者 Wei Du Pin-Song Zhao Min He Feng-Jie Lei 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期223-236,共14页
We present a study of low surface brightness galaxies(LSBGs) selected by fitting the images for all the galaxies inα.40 SDSS DR7 sample with two kinds of single-component models and two kinds of two-component models(... We present a study of low surface brightness galaxies(LSBGs) selected by fitting the images for all the galaxies inα.40 SDSS DR7 sample with two kinds of single-component models and two kinds of two-component models(disk+bulge):single exponential,single sersic,exponential+deVaucular(exp+deV),and exponential+sérsic(exp+ser).Under the criteria of the B band disk central surface brightness μ_(0,disk)(B)≥22.5 mag arcsec^(-2) and the axis ratio b/a> 0.3,we selected four none-edge-on LSBG samples from each of the models which contain 1105,1038,207,and 75 galaxies,respectively.There are 756 galaxies in common between LSBGs selected by exponential and sersic models,corresponding to 68.42% of LSBGs selected by the exponential model and 72.83% of LSBGs selected by the sersic model,the rest of the discrepancy is due to the difference in obtaining μ_(0) between the exponential and sersic models.Based on the fitting,in the range of 0.5≤n≤1.5,the relation of μ_(0) from two models can be written as μ_(0,sérsic)-μ_(0,exp)=-1.34(n-1).The LSBGs selected by disk+bulge models(LSBG_(2)comps) are more massive than LSBGs selected by single-component models(LSBG_1comp),and also show a larger disk component.Though the bulges in the majority of our LSBG_(2)comps are not prominent,more than 60% of our LSBG_(2)comps will not be selected if we adopt a single-component model only.We also identified 31 giant low surface brightness galaxies(gLSBGs) from LSBG_(2)comps.They are located at the same region in the color-magnitude diagram as other gLSBGs.After we compared different criteria of gLSBGs selection,we find that for gas-rich LSBGs,M_(*)> 10^(10)M_⊙ is the best to distinguish between gLSBGs and normal LSBGs with bulge. 展开更多
关键词 catalogs galaxies:spiral galaxies:bulges methods:data analysis methods:statistical
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The Clumpy Structure of Five Star-bursting Dwarf Galaxies in the MaNGA Survey
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作者 Mengting Ju Jun Yin +6 位作者 Lei Hao Chenxu Liu Chao-Wei Tsai Junfeng Wang Zhengyi Shao Shuai Feng Yu Rong 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期83-103,共21页
The star-forming clumps in star-bursting dwarf galaxies provide valuable insights into understanding the evolution of dwarf galaxies.In this paper,we focus on five star-bursting dwarf galaxies featuring off-centered c... The star-forming clumps in star-bursting dwarf galaxies provide valuable insights into understanding the evolution of dwarf galaxies.In this paper,we focus on five star-bursting dwarf galaxies featuring off-centered clumps in the Mapping Nearby Galaxies at Apache Point Observatory survey.Using the stellar population synthesis software Fitting Analysis using Differential evolution Optimization,we obtain the spatially resolved distribution of the star formation history,which allows us to construct the g-band images of the five galaxies at different ages.These images can help us to probe the evolution of the morphological structures of these galaxies.While images of a stellar population older than 1 Gyr are typically smooth,images of a stellar population younger than 1 Gyr reveal significant clumps,including multiple clumps which appear at different locations and even different ages.To study the evolutionary connections of these five galaxies to other dwarf galaxies before their star-forming clumps appear,we construct the images of the stellar populations older than three age nodes,and define them to be the images of the"host"galaxies.We find that the properties such as the central surface brightness and the effective radii of the hosts of the five galaxies are in between those of dwarf ellipticals(dEs)and dwarf irregulars(dIrrs),with two clearly more similar to dEs and one more similar to dIrrs.Among the five galaxies,8257-3704 is particularly interesting,as it shows a previous starburst event that is not quite visible from its gri image,but only visible from images of the stellar population at a few hundred million years.The star-forming clump associated with this event may have appeared at around 600 Myr ago and disappeared at around 40 Myr ago. 展开更多
关键词 galaxies dwarf-galaxies evolution-galaxies formation-Galaxy STRUCTURE
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Cosmological Constraints on Neutrino Masses in Light of JWST Red and Massive Candidate Galaxies
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作者 Jian-Qi Liu Zhi-Qi Huang Yan Su 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期7-12,共6页
The overabundance of the red and massive candidate galaxies observed by the James Webb Space Telescope(JWST)implies efficient structure formation or large star formation efficiency at high redshift z~10.In the scenari... The overabundance of the red and massive candidate galaxies observed by the James Webb Space Telescope(JWST)implies efficient structure formation or large star formation efficiency at high redshift z~10.In the scenario of a low or moderate star formation efficiency,because massive neutrinos tend to suppress the growth of structure of the universe,the JWST observation tightens the upper bound of the neutrino masses.Assuming A cold dark matter cosmology and a star formation efficiency∈[0.05,0.3](flat prior),we perform joint analyses of Planck+JWST and Planck+BAO+JWST,and obtain improved constraints∑m_(ν)<0.196 eV and ∑m_(ν)+<0.111 eV at 95% confidence level,respectively.Based on the above assumptions,the inverted mass ordering,which implies ∑m_(ν)≥0.1 eV,is excluded by Planck+BAO+JWST at 92.7% confidence level. 展开更多
关键词 (cosmology:)cosmological parameters galaxies:abundances galaxies:formation NEUTRINOS
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Comparing the Structural Parameters of the Milky Way to Other Spiral Galaxies
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作者 Jacob A.Guerrette Aleksandr V.Mosenkov +1 位作者 Dallin Spencer Zacory D.Shakespear 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期10-28,共19页
The structural parameters of a galaxy can be used to gain insight into its formation and evolution history.In this paper,we strive to compare the Milky Way’s structural parameters to other,primarily edge-on,spiral ga... The structural parameters of a galaxy can be used to gain insight into its formation and evolution history.In this paper,we strive to compare the Milky Way’s structural parameters to other,primarily edge-on,spiral galaxies in order to determine how our Galaxy measures up to the Local Universe.For our comparison,we use the galaxy structural parameters gathered from a variety of literature sources in the optical and near-infrared wave bands.We compare the scale length,scale height,and disk flatness for both the thin and thick disks,the thick-to-thin disk mass ratio,the bulge-to-total luminosity ratio,and the mean pitch angle of the Milky Way’s spiral arms to those in other galaxies.We conclude that many of the Milky Way’s structural parameters are largely ordinary and typical of spiral galaxies in the Local Universe,though the Galaxy’s thick disk appears to be appreciably thinner and less extended than expected from zoom-in cosmological simulations of Milky Way-mass galaxies with a significant contribution of galaxy mergers involving satellite galaxies. 展开更多
关键词 GALAXY disk-galaxies fundamental parameters-Galaxy STRUCTURE
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The Mass Assembly History for Galaxies with MaNGA
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作者 Xue Ge Hong-Tao Wang +3 位作者 Cheng-Long Lei Yun-Jun Guo Yi-Long Jiang Xiao-Xiao Cao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期58-69,共12页
How galaxies assemble masses through their own star formation or interaction with the external environment is still an important topic in the field of galaxy formation and evolution.We use Value Added Catalogs with ga... How galaxies assemble masses through their own star formation or interaction with the external environment is still an important topic in the field of galaxy formation and evolution.We use Value Added Catalogs with galaxy features that are spatially and temporally resolved from Sloan Digital Sky Survey Data Release 17 to investigate the mass growth histories of early-type galaxies(ETGs)and late-type galaxies(LTGs).We find that the mass growth of ETGs is earlier than that of LTGs for massive galaxies(M_(*)>10^(10)M_⊙),while low-mass(M_(*)≤10^(10)M_⊙)ETGs have statistically similar mass assembly histories as low-mass LTGs.The stellar metallicity of all massive galaxies shows a negative gradient and basically does not change with time.However,in low-mass galaxies,the stellar metallicity gradient of elliptical galaxies is negative,and the stellar metallicity gradient of lenticular and spiral galaxies evolves from positive to negative.ETGs are not all in a high-density environment,but exhibit mass dependence.As the tidal strength increases,the star formation rate of low-mass ETGs rapidly decreases.These results support a picture where massive galaxies exhibit inside-out quenching mode,while low-mass galaxies show outside-in quenching mode.Environmental effects play an important role in regulating the mass assembly histories of low-mass ETGs. 展开更多
关键词 GALAXY evolution-galaxies star formation-Galaxy FORMATION
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Quantifying the Tension between Cosmological Models and JWST Red Candidate Massive Galaxies
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作者 Jun-Chao Wang Zhi-Qi Huang +1 位作者 Lu Huang Jianqi Liu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期1-6,共6页
We develop a Python tool to estimate the tail distribution of the number of dark matter halos beyond a mass threshold and in a given volume in a light-cone.The code is based on the extended Press-Schechter model and i... We develop a Python tool to estimate the tail distribution of the number of dark matter halos beyond a mass threshold and in a given volume in a light-cone.The code is based on the extended Press-Schechter model and is computationally efficient,typically taking a few seconds on a personal laptop for a given set of cosmological parameters.The high efficiency of the code allows a quick estimation of the tension between cosmological models and the red candidate massive galaxies released by the James Webb Space Telescope,as well as scanning the theory space with the Markov Chain Monte Carlo method.As an example application,we use the tool to study the cosmological implication of the candidate galaxies presented in Labbéet al.The standard Λcold dark matter(ΛCDM)model is well consistent with the data if the star formation efficiency can reach~0.3 at high redshift.For a low star formation efficiency ε~0.1,theΛCDM model is disfavored at~2σ-3σconfidence level. 展开更多
关键词 (cosmology:)cosmological parameters Galaxy:abundances Galaxy:formation
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Formation of Superthin Galaxies in IllustrisTNG
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作者 Jianhong Hu Dandan Xu Cheng Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第7期235-248,共14页
Superthin galaxies are observed to have stellar disks with extremely small minor-to-major axis ratios.In this work,we investigate the formation of superthin galaxies in the TNG100 simulation.We trace the merger histor... Superthin galaxies are observed to have stellar disks with extremely small minor-to-major axis ratios.In this work,we investigate the formation of superthin galaxies in the TNG100 simulation.We trace the merger history and investigate the evolution of galaxy properties of a selected sample of superthin galaxies and a control sample of galaxies that share the same joint probability distribution in the stellar-mass and color diagram.Through making comparisons between the two galaxy samples,we find that present-day superthin galaxies had similar morphologies as the control sample counterparts at higher redshifts,but have developed extended flat“superthin”morphologies since z~1.During this latter evolution stage,superthin galaxies undergo an overwhelmingly higher frequency of prograde mergers(with orbit-spin angleθ_(orb)≤40°).Accordingly the spins of their dark matter halos have grown significantly and become noticeably higher than those of their normal disk counterparts.This further results in the buildup of their stellar disks at larger distances much beyond the regimes of normal disk galaxies.We also discuss the formation scenario of those superthin galaxies that live in larger dark matter halos as satellite galaxies therein. 展开更多
关键词 galaxies formation-galaxies evolution-galaxies interactions-galaxies star formation
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Isotherm,kinetic and thermodynamic investigations of boron phosphide to remove methylene blue from aqueous solution
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作者 YILDIRIM Furkan Murat ISIK Birol UGRASKAN Volkan 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3034-3049,共16页
In this work,the boron phosphide(BP)was synthesized and used for the adsorptive removal of methylene blue(MB)dye from aqueous solutions.To determine the optimum adsorption conditions,studies were performed by varying ... In this work,the boron phosphide(BP)was synthesized and used for the adsorptive removal of methylene blue(MB)dye from aqueous solutions.To determine the optimum adsorption conditions,studies were performed by varying parameters of temperature(298–328 K),pH(2–12),contact time(0–120 min),adsorbent dose(0.01–0.20 g/50 mL),and dye concentration(10–50 mg/L).Different isotherm and kinetic models were applied to the adsorption data.The linear correlations coefficient showed that the Langmuir isotherm best fits(R^(2)=0.9996).The maximum adsorption capacity of BP was obtained as 555.56 mg/g at 55℃and the removal rate reached up to 84.11%.Additionally,the pseudo-second-order kinetic model described the adsorption process best(R^(2)=0.9998).The thermodynamic studies represented that the adsorption occurred spontaneously(ΔG_(A)^(Θ)=−24.90 kJ/mol)and endothermically(ΔH_(A)^(Θ)=16.67 kJ/mol).The results showed that BP is an efficient adsorbent for removing cationic dyes from aqueous solutions. 展开更多
关键词 adsorption boron phosphide methylene blue
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On the Relation Between Symmetry of Radio Galaxies and Their Physical Parameters
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作者 Mohsen Javaherian Halime Miraghaei Hooman Moradpour 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第9期37-59,共23页
Gravity as a fundamental force plays a dominant role in the formation and evolution of cosmic objects and leaves its effect in the emergence of symmetric and asymmetric structures.Thus,analyzing the symmetry criteria ... Gravity as a fundamental force plays a dominant role in the formation and evolution of cosmic objects and leaves its effect in the emergence of symmetric and asymmetric structures.Thus,analyzing the symmetry criteria allows us to uncover mechanisms behind the gravity interaction and understand the underlying physical processes that contribute to the formation of large-scale structures such as galaxies.We use a segmentation process using intensity thresholding and the k-means clustering algorithm to analyze radio galaxy images.We employ a symmetry criterion and explore the relation between morphological symmetry in radio maps and host galaxy properties.Optical properties(stellar mass,black hole mass,optical size(R_(50)),concentration,stellar mass surface density(μ_(50)),and stellar age)and radio properties(radio flux density,radio luminosity,and radio size)are considered.We found that there is a correlation between symmetry and radio size,indicating larger radio sources have smaller symmetry indices.Therefore,size of radio sources should be considered in any investigation of symmetry.Weak correlations are also observed with other properties,such as R_(50)for FRI galaxies and stellar age.We compare the symmetry differences between FRI and FRII radio galaxies.FRII galaxies show higher symmetry in 1.4 GHz and 150 MHz maps.Investigating the influence of radio source sizes,we discovered that this result is independent of the sizes of radio sources.These findings contribute to our understanding of the morphological properties and analyses of radio galaxies. 展开更多
关键词 methods:data analysis techniques:image processing catalogs galaxies:nuclei galaxies:distances and redshifts
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Close Major-merger Pairs at z=0: Star-forming Galaxies with Pseudobulges
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作者 何川 徐聪 +5 位作者 Ute Lisenfeld 戴昱 方陶陶 黄家声 王炜 余清正 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第5期35-60,共26页
We present a study of star-forming galaxies (SFGs) with pseudobulges (bulges with Sérsic index n<2) in a loca close major-merger galaxy pair sample (H-KPAIR).With data from new aperture photometries in the opt... We present a study of star-forming galaxies (SFGs) with pseudobulges (bulges with Sérsic index n<2) in a loca close major-merger galaxy pair sample (H-KPAIR).With data from new aperture photometries in the optical and near-infrared bands (aperture size of 7 kpc) and from the literature,we find that the mean Age of central stellar populations in Spirals with pseudobulges is consistent with that of disky galaxies and is nearly constant against the bulge-to-total ratio (B/T).Paired Spirals have a slightly lower fraction of pure disk galaxies (B/T≤0.1) than their counterparts in the control sample.Compared to SFGs with classical bulges,those with pseudobulges have a higher (>2σ) mean of specific star formation rate (sSFR) enhancement (sSFR_(enh)=0.33±0.07 versus sSFR_(enh)=0.12±0.06) and broader scatter (by~1 dex).The eight SFGs that have the highest sSFR_(enh)in the sample all have pseudobulges.A majority (69%) of paired SFGs with strong enhancement (having sSFR more than5 times the median of the control galaxies) have pseudobulges.The Spitzer data show that the pseudobulges in these galaxies are tightly linked to nuclear/circum-nuclear starbursts.Pseudobulge SFGs in S+S and in S+E pairs have significantly (>3σ) different sSFR enhancement,with the means of sSFR_(enh)=0.45±0.08 and-0.04±0.11respectively.We find a decrease in the sSFR enhancements with the density of the environment for SFGs with pseudobulges.Since a high fraction (5/11) of pseudobulge SFGs in S+E pairs are in rich groups/clusters (loca density N_(1Mpc)≥7),the dense environment might be the cause for their low s SFR_(enh). 展开更多
关键词 galaxies evolution-galaxies interactions-galaxies star formation-galaxies structure-galaxies bulges-galaxies PHOTOMETRY
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Cross-method Analysis of Corotation Radii Data Set for Spiral Galaxies
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作者 V.S.Kostiuk A.A.Marchuk A.S.Gusev 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第7期95-110,共16页
A corotation radius is a key characteristic of disk galaxies that is essential to determine the angular speed of the spiral structureΩ_p,and therefore understand its nature.In the literature,there are plenty of metho... A corotation radius is a key characteristic of disk galaxies that is essential to determine the angular speed of the spiral structureΩ_p,and therefore understand its nature.In the literature,there are plenty of methods to estimate this value,but do these measurements have any consistency?In this work,we collected a data set of corotation radius measurements for 547 galaxies,300 of which had at least two values.An initial analysis reveals that most objects have rather inconsistent corotation radius positions.Moreover,a significant fraction of galactic disks is distinguished by a large error coverage and almost uniform distribution of measurements.These findings do not have any relation to spiral type,Hubble classification,or presence of a bar.Among other reasons,obtained results could be explained by the transient nature of spirals in a considerable part of galaxies.We have made our collected data sample publicly available,and have demonstrated on one example how it could be useful for future research by investigating a winding time value for a sample of galaxies with possible multiple spiral arm patterns. 展开更多
关键词 galaxies fundamental parameters-galaxies kinematics and dynamics-galaxies STRUCTURE
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