AIM: To investigate the levels of serum soluble intercellular adhesion molecules-1 (sICAM-1) and neutrophilic expression of CD18 in patients with various stages of diabetic retinopathy and to determine their different...AIM: To investigate the levels of serum soluble intercellular adhesion molecules-1 (sICAM-1) and neutrophilic expression of CD18 in patients with various stages of diabetic retinopathy and to determine their different expression pattern in the development of diabetic retinopathy(DR). METHODS: Levels of serum sICAM-1 and CD18 on the surface of neutrophile were measured in 41 DR patients, they were classified in three subgroups according to the stage of retinopathy as determined by fund's ophthalmoscopy; 10 control subjects were also studied. sICAM-1 were measured by enzyme-linked immunosorbent assay and CD18 by flow cytometry. RESULTS: The neutrophilic CD18 expression and serum sICAM-1 level were all significantly elevated in all diabetic subgroups compared to control subjects (P <0.01). The differences of CD18 and sICAM-1 among the diabetic subgroups were significant in CD18 but not in sICAM-1. The progression of retinopathy was associated with an increase both in CD18 and in sICAM-1 levels by simple correlation analysis (beta =0.74, P<0.001; beta =0.38, P<0.01, respectively). But stepwise multiple regression analysis revealed that only CD18 Was independent determinant of retinopathy (beta =1.04, P<0.01). CONCLUSION: Our results confirm the contribution of endothelial and neutrophilic activation in the development of DR as indicated by increased levels of CD18 and sICAM-1. However, a direct implication of CD18 and ICAM-1 in the progression of DR can be supported only in the CD18 but not ICAM-1. CD18 and ICAM-1 may play different role in the development of diabetic retinopathy.展开更多
The C_(2)H N=1-0 transition was used to investigate the possible line of sight sub-structures from the dense and optically thick in 13CO J=1-0 regions in the Ophiuchus star-forming molecular cloud.With a 0.2 K or lowe...The C_(2)H N=1-0 transition was used to investigate the possible line of sight sub-structures from the dense and optically thick in 13CO J=1-0 regions in the Ophiuchus star-forming molecular cloud.With a 0.2 K or lower noise,multi-peak spectra were obtained and then used for identifying sub-structures.There are clues,e.g.,the core velocity dispersion remains unchanged with the increasing scale that this cloud has a mild thickness in the line of sight direction and a large amount of overlapping CO cores,as expected,at least two coherent layers have been found.The integrated intensity maps of these two layers are different in shape and morphology.Inferred from the point velocity dispersion,one sub-structure with a thickness of∼1 pc was found,while other substructures were more likely to be fragments.展开更多
We obtain the rotational spectra for cyanopolyynes HC_(2n+1)N(n=0-8)and their cations through quantum chemical calculations.Rotational constants,quartic centrifugal distortion constants,and hyperfine constants are cal...We obtain the rotational spectra for cyanopolyynes HC_(2n+1)N(n=0-8)and their cations through quantum chemical calculations.Rotational constants,quartic centrifugal distortion constants,and hyperfine constants are calculated.The rotational constants are determined at the theoretical level of B3PW91/cc-pVTZ,incorporating with the calibration for the moment of inertia.This significantly improves the accuracy with respect to the uncalibrated ones.Quartic centrifugal distortion constants are estimated using the empirical relation,achieving an accuracy of∼0.02%with respect to the experiment.Hyperfine constants are computed at the B3PW91/6-311+G(df,pd)and B3PW91/aug-cc-pVTZ levels.The overall frequency characteristics of all the target molecules are discussed and their detectability in the interstellar medium is also quantitatively evaluated.The rotational spectra of selected species(HC_(13)N,HC_(15)N,HC_(17)N,and HC_(5)N^(+))are reproduced,showing satisfied consistency with experiments or observations.Our results provide useful reference for observations and experiments,even that more advanced calculation levels and basis sets are required to achieve better accuracy.展开更多
OBJECTIVE: To study the ehanges of platelet endothelial cell adhesion molecule-1 (PECAM-1) expression on polymorphonuclear leukocytes (PMNs) in peripheral circulation anti pancreatic microcirculation in rats with acut...OBJECTIVE: To study the ehanges of platelet endothelial cell adhesion molecule-1 (PECAM-1) expression on polymorphonuclear leukocytes (PMNs) in peripheral circulation anti pancreatic microcirculation in rats with acute edematous pancreatitis (AEP). METHODS: The model of AEP was established with 50 Wistar rats, and the changes of PECAM-1 expression on PMNs from the splenic vein and inferior vena cava were determined by flow cytometry. RESULTS: PECAM-I expression on PMNs showed no significant difference between pancreatic microcirculation and peripheral circulation at AEP2h and AEP4h time points. From the AEP4h to the AEP8h time point, PECAM-1 expression in peripheral circulation was up-regulated, but PECAM-1 expression in pancreatic microcirculation was down-regulated. PECAM-1 expression had a significant difference between pancreatic microcirculation and peripheral circulation at the AEP8h time point (P<0.05). CONCLUSION: PECAM-1 expression on PMNs is in a converse way between pancreatic microcirculation and peripheral circulation in AEP.展开更多
A filament is an important structure for studying star formation,especially intersections of filaments which are believed to be more dense than other regions.Identifying filament intersections is the first step in stu...A filament is an important structure for studying star formation,especially intersections of filaments which are believed to be more dense than other regions.Identifying filament intersections is the first step in studying them.Current methods can only extract two-dimensional intersections without considering the velocity dimension.In this paper,we propose a method to identify three-dimensional(3 D)intersections by combining Harris Corner Detection and Hough Line Transform,which achieve a precision of 98%.We apply this method for extracting intersection structures of the OMC-2/3 molecular cloud and to study its physical properties and obtain the associated PDF distribution.Results show denser gas is concentrated in those 3 D intersections.展开更多
The excitation temperature T_(ex)for molecular emission and absorption lines is an essential parameter for interpreting the molecular environment.This temperature can be obtained by observing multiple molecular transi...The excitation temperature T_(ex)for molecular emission and absorption lines is an essential parameter for interpreting the molecular environment.This temperature can be obtained by observing multiple molecular transitions or hyperfine structures of a single transition,but it remains unknown for a single transition without hyperfine structure lines.Earlier H_(2)CO absorption experiments for a single transition without hyperfine structures adopted a constant value of T_(ex),which is not correct for molecular regions with active star formation and H II regions.For H_(2)CO,two equations with two unknowns may be used to determine the excitation temperature T_(ex)and the optical depthτ,if other parameters can be determined from measurements.Published observational data of the4.83 GHz(λ=6 cm)H_(2)CO(1_(10)-1_(11))absorption line for three star formation regions,W40,M17 and DR17,have been used to verify this method.The distributions of T_(ex)in these sources are in good agreement with the contours of the H110αemission of the H II regions in M17 and DR17 and with the H_(2)CO(1_(10)-1_(11))absorption in W40.The distributions of T_(ex)in the three sources indicate that there can be significant variation in the excitation temperature across star formation and H II regions and that the use of a fixed(low)value results in misinterpretation.展开更多
Stars form through the gravitational collapse of molecular cloud cores.Before collapsing,the cores are supported by thermal pressure and turbulent motions.A question of critical importance for the understanding of sta...Stars form through the gravitational collapse of molecular cloud cores.Before collapsing,the cores are supported by thermal pressure and turbulent motions.A question of critical importance for the understanding of star formation is how to observationally discern whether a core has already initiated gravitational collapse or is still in hydrostatic balance.The canonical method to identify gravitational collapse is based on the observed radial density profile,which would change from Bonnor-Ebert type toward power laws as the core collapses.In practice,due to the projection effect,the resolution limit and other caveats,it has been difficult to directly reveal the dynamical status of cores,particularly in massive star forming regions.We here propose a novel,straightforward diagnostic,namely,the collapsing index(CI),which can be modeled and calculated based on the radial profile of the line width of dense gas.A meaningful measurement of CI requires spatially and spectrally resolved images of optically thin and chemically stable dense gas tracers.ALMA observations are making such data sets increasingly available for massive star forming regions.Applying our method to one of the deepest dense-gas spectral images ever taken toward such a region,namely,the Orion molecular cloud,we detect the dynamical status of selected cores.We observationally distinguished a collapsing core in a massive star forming region from a hydrostatical one.Our approach would help significantly improve our understanding of the interaction between gravity and turbulence within molecular cloud cores in the process of star formation.展开更多
We report the results of ^12CO of Ultra-Compact （UC） HII regions with and ^13CO J=1-0 observations of eight candidates the Purple Mountain Observatory （PMO） Qinghai 13.7 -m telescope, which resulted in revealing 1...We report the results of ^12CO of Ultra-Compact （UC） HII regions with and ^13CO J=1-0 observations of eight candidates the Purple Mountain Observatory （PMO） Qinghai 13.7 -m telescope, which resulted in revealing 11 molecular cores. Their masses range from 130 to 1.7 × 10^4 M⊙, with different spatial scales （1 - 6 pc）. Also presented are the relevant HCO＋ j=1-0 maps, which enabled us to investigate more detailed structures of these cores. Further comparisons show that four of the cores deviated from the centers of infrared （MIR） emission of Midcourse Space Experiment （MSX）, while others correspond either to bright MIR sources or diffuse MIR background. This indicates various evolutionary phases of the cores, including quite early ones for those without MIR sources.展开更多
Phenol,which belongs to the C_(6)H_(6)O isomeric group,is the simplest molecule in the family of alcohol of the aromatic series.Although phenol has yet to be detected in the interstellar medium,a tentative identificat...Phenol,which belongs to the C_(6)H_(6)O isomeric group,is the simplest molecule in the family of alcohol of the aromatic series.Although phenol has yet to be detected in the interstellar medium,a tentative identification was reported toward the Orion KL hot core using the IRAM-30 m line survey.To explore some more species of this isomeric group,we consider ten species to study the fate of their astronomical detection.It is noticed that phenol is the most energetically favorable isomer of this group.In contrast,propargyl ether is the least favorable(having relative energy~103kcal mol^(-1)compared to phenol)species of this group.So far,the studies associated with the formation of phenol are heavily concentrated on combustion chemistry.Here,we suggest a few key reactions(C_(6)H_(6)+OH→C_(6)H_(5)+H_(2)O,C_(6)H_(6)+O→C_(6)H_(5)OH,C_(6)H_(6)+H→C_(6)H_(5)+H_(2),and C_(6)H_(5)+OH→C_(6)H_(5)OH+hν)for the formation of phenol.All these pathways are included in a large gas-grain chemical network to study its formation in high mass star-forming regions and dark cloud environments.It is noticed that the phenyl(-C_(6)H_(5))formation by the ice-phase hydrogen abstraction reaction of benzene(i.e.,C_(6)H_(6)+OH→C_(6)H_(5)+H_(2)O if allowed at~10 K)could serve as the starting point for the formation of phenol in the gas phase by radiative association reaction C_(6)H_(5)+OH→C_(6)H_(5)OH+hν.The gasphase reaction C_(6)H_(6)+O→C_(6)H_(5)OH significantly contributes to the formation of phenol,when the ice-phase reaction C_(6)H_(6)+OH→C_(6)H_(5)+H_(2)O is not considered at low temperature.Band 4 ALMA archival data of a hot molecular core,G10.47+0.03,are analyzed.It yields an upper limit on phenol abundance of 5.19×10^(-9).Our astrochemical model delivers an upper limit on phenol abundance of~2.20×10^(-9)in the hot molecular core,whereas its production in the dark cloud is not satisfactory.展开更多
基金Supported by Natural Science Foundation of Shaanxi Province, China (No. 2011JM4048)
文摘AIM: To investigate the levels of serum soluble intercellular adhesion molecules-1 (sICAM-1) and neutrophilic expression of CD18 in patients with various stages of diabetic retinopathy and to determine their different expression pattern in the development of diabetic retinopathy(DR). METHODS: Levels of serum sICAM-1 and CD18 on the surface of neutrophile were measured in 41 DR patients, they were classified in three subgroups according to the stage of retinopathy as determined by fund's ophthalmoscopy; 10 control subjects were also studied. sICAM-1 were measured by enzyme-linked immunosorbent assay and CD18 by flow cytometry. RESULTS: The neutrophilic CD18 expression and serum sICAM-1 level were all significantly elevated in all diabetic subgroups compared to control subjects (P <0.01). The differences of CD18 and sICAM-1 among the diabetic subgroups were significant in CD18 but not in sICAM-1. The progression of retinopathy was associated with an increase both in CD18 and in sICAM-1 levels by simple correlation analysis (beta =0.74, P<0.001; beta =0.38, P<0.01, respectively). But stepwise multiple regression analysis revealed that only CD18 Was independent determinant of retinopathy (beta =1.04, P<0.01). CONCLUSION: Our results confirm the contribution of endothelial and neutrophilic activation in the development of DR as indicated by increased levels of CD18 and sICAM-1. However, a direct implication of CD18 and ICAM-1 in the progression of DR can be supported only in the CD18 but not ICAM-1. CD18 and ICAM-1 may play different role in the development of diabetic retinopathy.
基金supported by the National SKA Program of China No.2020SKA0120100the National Natural Science Foundation of China(NSFC)under grant Nos.12003047,11773041,U2031119,12173052,and 12173053+1 种基金Both Lei Qian and Zhichen Pan were supported by the Youth Innovation Promotion Association of CAS(id.2018075,Y2022027,and 2023064)the CAS“Light of West China”Program.
文摘The C_(2)H N=1-0 transition was used to investigate the possible line of sight sub-structures from the dense and optically thick in 13CO J=1-0 regions in the Ophiuchus star-forming molecular cloud.With a 0.2 K or lower noise,multi-peak spectra were obtained and then used for identifying sub-structures.There are clues,e.g.,the core velocity dispersion remains unchanged with the increasing scale that this cloud has a mild thickness in the line of sight direction and a large amount of overlapping CO cores,as expected,at least two coherent layers have been found.The integrated intensity maps of these two layers are different in shape and morphology.Inferred from the point velocity dispersion,one sub-structure with a thickness of∼1 pc was found,while other substructures were more likely to be fragments.
基金funded by the Scientific Research Foundation of Education Bureau of Hunan Province(No.23A0132)the National Natural Science Foundation of China(NSFC)under Nos.12333005,12122302 and 62205278the Innovative Research Group Project of Natural Science Foundation of Hunan Province of China No.2024JJ1008.
文摘We obtain the rotational spectra for cyanopolyynes HC_(2n+1)N(n=0-8)and their cations through quantum chemical calculations.Rotational constants,quartic centrifugal distortion constants,and hyperfine constants are calculated.The rotational constants are determined at the theoretical level of B3PW91/cc-pVTZ,incorporating with the calibration for the moment of inertia.This significantly improves the accuracy with respect to the uncalibrated ones.Quartic centrifugal distortion constants are estimated using the empirical relation,achieving an accuracy of∼0.02%with respect to the experiment.Hyperfine constants are computed at the B3PW91/6-311+G(df,pd)and B3PW91/aug-cc-pVTZ levels.The overall frequency characteristics of all the target molecules are discussed and their detectability in the interstellar medium is also quantitatively evaluated.The rotational spectra of selected species(HC_(13)N,HC_(15)N,HC_(17)N,and HC_(5)N^(+))are reproduced,showing satisfied consistency with experiments or observations.Our results provide useful reference for observations and experiments,even that more advanced calculation levels and basis sets are required to achieve better accuracy.
文摘OBJECTIVE: To study the ehanges of platelet endothelial cell adhesion molecule-1 (PECAM-1) expression on polymorphonuclear leukocytes (PMNs) in peripheral circulation anti pancreatic microcirculation in rats with acute edematous pancreatitis (AEP). METHODS: The model of AEP was established with 50 Wistar rats, and the changes of PECAM-1 expression on PMNs from the splenic vein and inferior vena cava were determined by flow cytometry. RESULTS: PECAM-I expression on PMNs showed no significant difference between pancreatic microcirculation and peripheral circulation at AEP2h and AEP4h time points. From the AEP4h to the AEP8h time point, PECAM-1 expression in peripheral circulation was up-regulated, but PECAM-1 expression in pancreatic microcirculation was down-regulated. PECAM-1 expression had a significant difference between pancreatic microcirculation and peripheral circulation at the AEP8h time point (P<0.05). CONCLUSION: PECAM-1 expression on PMNs is in a converse way between pancreatic microcirculation and peripheral circulation in AEP.
基金supported by the National Natural Science Foundation of China(Grant Nos.11988101,11725313,11403041,11373038 and 11373045)CAS International Partnership Program(No.114A11KYSB20160008)the Young Researcher Grant of National Astronomical Observatories,Chinese Academy of Sciences.
文摘A filament is an important structure for studying star formation,especially intersections of filaments which are believed to be more dense than other regions.Identifying filament intersections is the first step in studying them.Current methods can only extract two-dimensional intersections without considering the velocity dimension.In this paper,we propose a method to identify three-dimensional(3 D)intersections by combining Harris Corner Detection and Hough Line Transform,which achieve a precision of 98%.We apply this method for extracting intersection structures of the OMC-2/3 molecular cloud and to study its physical properties and obtain the associated PDF distribution.Results show denser gas is concentrated in those 3 D intersections.
基金funded by the National Key R&D Program of China under grant No.2022YFA1603103partially funded by the Regional Collaborative Innovation Project of Xinjiang Uyghur Autonomous Region under grant No.2022E01050+7 种基金the Tianshan Talent Program of Xinjiang Uygur Autonomous Region under grant No.2022TSYCLJ0005the Natural Science Foundation of Xinjiang Uygur Autonomous Region under grant No.2022D01E06the Chinese Academy of Sciences(CAS)Light of West China Program under grants Nos.xbzg-zdsys-202212,2020-XBQNXZ-017,and 2021-XBQNXZ-028the National Natural Science Foundation of China(NSFC,grant Nos.12173075,11973076,and 12103082)the Xinjiang Key Laboratory of Radio Astrophysics under grant No.2022D04033the Youth Innovation Promotion Association CASfunded by the Chinese Academy of Sciences Presidents International Fellowship Initiative under grants Nos.2022VMA0019 and 2023VMA0030funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan under grant No.AP13067768。
文摘The excitation temperature T_(ex)for molecular emission and absorption lines is an essential parameter for interpreting the molecular environment.This temperature can be obtained by observing multiple molecular transitions or hyperfine structures of a single transition,but it remains unknown for a single transition without hyperfine structure lines.Earlier H_(2)CO absorption experiments for a single transition without hyperfine structures adopted a constant value of T_(ex),which is not correct for molecular regions with active star formation and H II regions.For H_(2)CO,two equations with two unknowns may be used to determine the excitation temperature T_(ex)and the optical depthτ,if other parameters can be determined from measurements.Published observational data of the4.83 GHz(λ=6 cm)H_(2)CO(1_(10)-1_(11))absorption line for three star formation regions,W40,M17 and DR17,have been used to verify this method.The distributions of T_(ex)in these sources are in good agreement with the contours of the H110αemission of the H II regions in M17 and DR17 and with the H_(2)CO(1_(10)-1_(11))absorption in W40.The distributions of T_(ex)in the three sources indicate that there can be significant variation in the excitation temperature across star formation and H II regions and that the use of a fixed(low)value results in misinterpretation.
文摘Stars form through the gravitational collapse of molecular cloud cores.Before collapsing,the cores are supported by thermal pressure and turbulent motions.A question of critical importance for the understanding of star formation is how to observationally discern whether a core has already initiated gravitational collapse or is still in hydrostatic balance.The canonical method to identify gravitational collapse is based on the observed radial density profile,which would change from Bonnor-Ebert type toward power laws as the core collapses.In practice,due to the projection effect,the resolution limit and other caveats,it has been difficult to directly reveal the dynamical status of cores,particularly in massive star forming regions.We here propose a novel,straightforward diagnostic,namely,the collapsing index(CI),which can be modeled and calculated based on the radial profile of the line width of dense gas.A meaningful measurement of CI requires spatially and spectrally resolved images of optically thin and chemically stable dense gas tracers.ALMA observations are making such data sets increasingly available for massive star forming regions.Applying our method to one of the deepest dense-gas spectral images ever taken toward such a region,namely,the Orion molecular cloud,we detect the dynamical status of selected cores.We observationally distinguished a collapsing core in a massive star forming region from a hydrostatical one.Our approach would help significantly improve our understanding of the interaction between gravity and turbulence within molecular cloud cores in the process of star formation.
基金the National Natural Science Foundation of China
文摘We report the results of ^12CO of Ultra-Compact （UC） HII regions with and ^13CO J=1-0 observations of eight candidates the Purple Mountain Observatory （PMO） Qinghai 13.7 -m telescope, which resulted in revealing 11 molecular cores. Their masses range from 130 to 1.7 × 10^4 M⊙, with different spatial scales （1 - 6 pc）. Also presented are the relevant HCO＋ j=1-0 maps, which enabled us to investigate more detailed structures of these cores. Further comparisons show that four of the cores deviated from the centers of infrared （MIR） emission of Midcourse Space Experiment （MSX）, while others correspond either to bright MIR sources or diffuse MIR background. This indicates various evolutionary phases of the cores, including quite early ones for those without MIR sources.
基金the SVMCM scholarship,Government of West Bengalthe DST-INSPIRE Fellowship scheme for financial assistancethe CSIR fellowship。
文摘Phenol,which belongs to the C_(6)H_(6)O isomeric group,is the simplest molecule in the family of alcohol of the aromatic series.Although phenol has yet to be detected in the interstellar medium,a tentative identification was reported toward the Orion KL hot core using the IRAM-30 m line survey.To explore some more species of this isomeric group,we consider ten species to study the fate of their astronomical detection.It is noticed that phenol is the most energetically favorable isomer of this group.In contrast,propargyl ether is the least favorable(having relative energy~103kcal mol^(-1)compared to phenol)species of this group.So far,the studies associated with the formation of phenol are heavily concentrated on combustion chemistry.Here,we suggest a few key reactions(C_(6)H_(6)+OH→C_(6)H_(5)+H_(2)O,C_(6)H_(6)+O→C_(6)H_(5)OH,C_(6)H_(6)+H→C_(6)H_(5)+H_(2),and C_(6)H_(5)+OH→C_(6)H_(5)OH+hν)for the formation of phenol.All these pathways are included in a large gas-grain chemical network to study its formation in high mass star-forming regions and dark cloud environments.It is noticed that the phenyl(-C_(6)H_(5))formation by the ice-phase hydrogen abstraction reaction of benzene(i.e.,C_(6)H_(6)+OH→C_(6)H_(5)+H_(2)O if allowed at~10 K)could serve as the starting point for the formation of phenol in the gas phase by radiative association reaction C_(6)H_(5)+OH→C_(6)H_(5)OH+hν.The gasphase reaction C_(6)H_(6)+O→C_(6)H_(5)OH significantly contributes to the formation of phenol,when the ice-phase reaction C_(6)H_(6)+OH→C_(6)H_(5)+H_(2)O is not considered at low temperature.Band 4 ALMA archival data of a hot molecular core,G10.47+0.03,are analyzed.It yields an upper limit on phenol abundance of 5.19×10^(-9).Our astrochemical model delivers an upper limit on phenol abundance of~2.20×10^(-9)in the hot molecular core,whereas its production in the dark cloud is not satisfactory.
