The potential of the high resolution nuclear track detector (NTD) CR-39 is examined carefully for the measurement of relativistic nuclear projectile fragmentation cross sections and studies of related processes using ...The potential of the high resolution nuclear track detector (NTD) CR-39 is examined carefully for the measurement of relativistic nuclear projectile fragmentation cross sections and studies of related processes using the experience of many years of such measurements. The charge resolution and the charge resolving power of CR-39 detectors for the measurements of 158 A GeV 207Pb projectiles and their fragments are presented. Exposures of target-detector stacks, the chemical etching procedure and the nuclear track measurements are described in detail discussing precautions and possible errors. The procedures discussed are also valid for other NTDs. A comparison with electronic active detectors is also made considering important detection and measurement aspects. An experimental design proposing the co-use of NTDs with in-use active detectors is described.展开更多
本文对最高能量为500 A MeV的^(40)Ar与铜靶作用弹核碎裂电荷变化总截面及碎片产生分截面进行了实验研究,并与相近能区^(40)Ar诱发铜靶核碎裂的实验结果及理论模型计算结果进行了比较.结果表明:电荷变化总截面与相近能区实验结果一致,也...本文对最高能量为500 A MeV的^(40)Ar与铜靶作用弹核碎裂电荷变化总截面及碎片产生分截面进行了实验研究,并与相近能区^(40)Ar诱发铜靶核碎裂的实验结果及理论模型计算结果进行了比较.结果表明:电荷变化总截面与相近能区实验结果一致,也与Bradt-Peters及Nilsen半经验公式预言一致;NUCFRG2和PHITS模型预言低于实验结果.弹核碎片产生分截面在所研究的能区范围与束流能量没有明显依赖关系,EPAX3及FRACS半经验参数化公式可以较好地再现实验结果.展开更多
Background:The Emei Shan Liocichla(Liocichla omeiensis) is an endemic bird species to southwestern China with a small geographic range. However, little was known about the genetic status of this threatened species.Met...Background:The Emei Shan Liocichla(Liocichla omeiensis) is an endemic bird species to southwestern China with a small geographic range. However, little was known about the genetic status of this threatened species.Methods:We applied restriction-site-associated DNA sequencing(RAD-Seq) for rapid mass identification of microsatellite markers of the Emei Shan Liocichla.Results:A total of 11,564 microsatellite sequences were obtained, 600 random loci were designed for screening and 24 polymorphic microsatellite loci were selected for further validation. The average allele number, average observed heterozygosity and average expected heterozygosity were relatively low in our samples, which were 6.08, 0.6618 and 0.7048, respectively, indicating that the Emei Shan Liocichla might have lost some genetic diversity. Further analyses suggested that the populations distributed on two mountains(Daxiangling and Xiaoliangshan) showed a modest degree of genetic differentiation.Conclusions:These novel microsatellite markers provided valuable preliminary knowledge regarding the genetic status of the Emei Shan Liocichla and can be useful in further studies, as well as in the management and conservation of this species.展开更多
The emission angle distribution of projectile fragments(PFs)and the temperature of PF emission sources for fragmentation of 56Fe on polyethylene,carbon,and aluminum targets at the highest energy of 497 A MeV are inves...The emission angle distribution of projectile fragments(PFs)and the temperature of PF emission sources for fragmentation of 56Fe on polyethylene,carbon,and aluminum targets at the highest energy of 497 A MeV are investigated on the basis of corrected data,using a CR-39 plastic nuclear track detector.It is found that the average emission angle of PFs increases with the decrease in PF charge for the same target,and no obvious dependence of angular distribution on the mass of the target nucleus is found for the same PF.The cumulative squared transverse momentum distribution of PFs can be well represented by a single Rayleigh distribution.The temperature of PF emission sources is extracted from the distribution,and it is about 1.0-8.0 MeV and does not depend on the mass of the target for PFs with charges of 9≤Z≤25.展开更多
The multiplicity distribution, multiplicity moment, scaled variance, entropy and reduced entropy of target evaporated fragments emitted in forward and backward hemispheres in 12 A GeV ^4He, 3.7 A GeV ^16O, 60 A GeV ^1...The multiplicity distribution, multiplicity moment, scaled variance, entropy and reduced entropy of target evaporated fragments emitted in forward and backward hemispheres in 12 A GeV ^4He, 3.7 A GeV ^16O, 60 A GeV ^16O, 1.7 A GeV ^84Kr and 10.7 A GeV ^197Au -induced emulsion heavy target (AgBr) interactions are investigated. It is found that the multiplicity distribution of target evaporated fragments emitted in both forward and backward hemispheres can be fitted by a Gaussian distribution. The multiplicity moments of target evaporated particles emitted in the forward and backward hemispheres increase with the order of the moment q, and the secondorder multiplicity moment is energy independent over the entire energy range for all the interactions in the forward and backward hemisphere. The scaled variance, a direct measure of multiplicity fluctuations, is close to one for all the interactions, which indicate a correlation among the produced particles. The entropy of target evaporated fragments emitted in both forward and backward hemispheres are the same within experimental errors.展开更多
The topology of ^16 O fragmentation at 3.7 A GeV in reactions with emulsion nuclei is presented. The multiplicity distributions of projectile fragments, charged secondaries and their dependences on the projectile resi...The topology of ^16 O fragmentation at 3.7 A GeV in reactions with emulsion nuclei is presented. The multiplicity distributions of projectile fragments, charged secondaries and their dependences on the projectile residues are discussed.展开更多
Diabetes Mellitus is a chronic disease that affects important body organs in a very serious manner. The consequences of this disease turn out to be a significant problem for the patient, who tries to cope with the new...Diabetes Mellitus is a chronic disease that affects important body organs in a very serious manner. The consequences of this disease turn out to be a significant problem for the patient, who tries to cope with the new condition his organism has been placed in. The most common effect of the disease, hyperglycaemia, leads over time to serious damage to various body systems, such as nerves and blood vessels. What is not widely known among the population is that diabetes may have harmful effects on the reproductive system of the men suffering from diabetes type 1 and 2 and that such a parameter could lead to or might be the reason for infertility problems for couples, for example, miscarriage or embryonic failure. AGEs is a number of products which are believed to play an important role, because their presence has been detected in increased level in diabetic men. This implies that those glycation products might play a key role in diabetic complications. Their receptor, RAGE, member of the immunoglobulin superfamily has been detected in the reproductive tract of diabetic men. Reactive oxygen species (ROS), a possible product of AGEs appear in high levels in seminal plasma and are believed to be the cause of DNA fragmentation. The objective of this review was to gather all the available material i.e. studies on diabetes mellitus in one article, to study the research which has already been conducted and the conclusions that have been drawn, in order to offer, if possible, new pathways and perspectives to the scientists, who focus on fertility problems, sometimes intractable.展开更多
We use the bond percolation model to study the multifragrnentation of<sup>197</sup>Au projectiles interact-ing with Cu target at a bombarding energy of 600 MeV/u.The charge observables and some of their di...We use the bond percolation model to study the multifragrnentation of<sup>197</sup>Au projectiles interact-ing with Cu target at a bombarding energy of 600 MeV/u.The charge observables and some of their dif-ferential distributions are analyzed.The theoretical results agree well with the experimental data ofALADIN collaboration.This indicates that the percolation model can describe reasonably the universal be-havior of nuclear fragmentation in nucleus-nucleus collisions.展开更多
The properties of the relativistic helium fragments produced in interactions of ^84Kr at 1.8 A GeV and ^197Au at 10.7 A GeV in emulsion are investigated. The experimental results are compared with those obtained from ...The properties of the relativistic helium fragments produced in interactions of ^84Kr at 1.8 A GeV and ^197Au at 10.7 A GeV in emulsion are investigated. The experimental results are compared with those obtained from various projectiles with emulsion collisions at different energies. It is found that the multiplicity distribution of helium projectile fragments (HPFs) is well described by the Koba-Nielsen Olesen (KNO) scaling presentation. The second Mueller moment f2 of the HPF multiplicity distribution is independent of the projectile energy for the same projectile, but it is dependent on the projectile mass number. The value of f2 increases with the increase of projectile mass number Ap. The negative value of f2, when Ap 〈 69, means that the emission of HPFs is anticorrelated, but positive value of f2, when Ap 〉 69, refers to that the emission of HPFs is correlated. The non-zero f2 moment in this experiment implies the strong correlation existing between the HPFs.展开更多
The forward-backward multiplicity and correlations of a target evaporated fragment (black track particle) and target recoiled proton (grey track particle) emitted from 150 A MeV 4He, 290 A MeV ^12C, 400 A MeV ^12C...The forward-backward multiplicity and correlations of a target evaporated fragment (black track particle) and target recoiled proton (grey track particle) emitted from 150 A MeV 4He, 290 A MeV ^12C, 400 A MeV ^12C, 400 A MeV ^20Ne and 500 A MeV ^56Fe induced different types of nuclear emulsion target interactions are investigated. It is found that the forward and backward averaged multiplicity of a grey, black and heavily ionized track particle increases with the increase of the target size. The averaged multiplicity of a forward black track particle, backward black track particle, and backward grey track particle do not depend on the projectile size and energy, but the averaged multiplicity of a forward grey track particle increases with an increase of projectile size and energy. The backward grey track particle multiplicity distribution follows an exponential decay law and the decay constant decreases with an increase of target size. The backward-forward multiplicity correlations follow linear law which is independent of the projectile size and energy, and the saturation effect is observed in some heavy target data sets.展开更多
Multiplicity fluctuation of the target evaporated fragments emitted in 290 MeV/u 12C-AgBr, 400 MeV/u 12C-AgBr, 400 MeV/u 20Ne-AgBr and 500 MeV/u 56Fe-AgBr interactions is investigated using the scaled factorial moment...Multiplicity fluctuation of the target evaporated fragments emitted in 290 MeV/u 12C-AgBr, 400 MeV/u 12C-AgBr, 400 MeV/u 20Ne-AgBr and 500 MeV/u 56Fe-AgBr interactions is investigated using the scaled factorial moment method in two-dimensional normal phase space and cumulative variable space, respectively. It is found that in normal phase space the scaled factorial moment (ln(Fq)) increases linearly with the increase of the divided number of phase space (lnM) for lower q-value and increases linearly with the increase of lnM, and then becomes saturated or decreased for a higher q-value. In cumulative variable space ln(Fq) decreases linearly with increase of lnM. This indicates that no evidence of non-statistical multiplicity fluctuation is observed in our data sets. So, any fluctuation indicated in the results of normal variable space analysis is totally caused by the non-uniformity of the single-particle density distribution.展开更多
The projected angular distribution and transverse momentum distribution of proton projectile fragments produced in 3.7A GeV 160, 500A MeV 56Fe, and 1.7A GeV S4Kr induced by different kinds of emulsion target (H, CNO,...The projected angular distribution and transverse momentum distribution of proton projectile fragments produced in 3.7A GeV 160, 500A MeV 56Fe, and 1.7A GeV S4Kr induced by different kinds of emulsion target (H, CNO, and AgBr) interactions are investigated. It is found that the projected angular distribution and transverse momentum distribution can be well represented by a single Gaussian distribution. Comparison of transverse momentum distribution with the Maxwell-Boltzmann distribution reveals that proton projectile fragments are emitted from a single-temperature emission source. The temperature is different for different colliding systems, and linearly depends on the target size.展开更多
文摘The potential of the high resolution nuclear track detector (NTD) CR-39 is examined carefully for the measurement of relativistic nuclear projectile fragmentation cross sections and studies of related processes using the experience of many years of such measurements. The charge resolution and the charge resolving power of CR-39 detectors for the measurements of 158 A GeV 207Pb projectiles and their fragments are presented. Exposures of target-detector stacks, the chemical etching procedure and the nuclear track measurements are described in detail discussing precautions and possible errors. The procedures discussed are also valid for other NTDs. A comparison with electronic active detectors is also made considering important detection and measurement aspects. An experimental design proposing the co-use of NTDs with in-use active detectors is described.
文摘本文对最高能量为500 A MeV的^(40)Ar与铜靶作用弹核碎裂电荷变化总截面及碎片产生分截面进行了实验研究,并与相近能区^(40)Ar诱发铜靶核碎裂的实验结果及理论模型计算结果进行了比较.结果表明:电荷变化总截面与相近能区实验结果一致,也与Bradt-Peters及Nilsen半经验公式预言一致;NUCFRG2和PHITS模型预言低于实验结果.弹核碎片产生分截面在所研究的能区范围与束流能量没有明显依赖关系,EPAX3及FRACS半经验参数化公式可以较好地再现实验结果.
基金supported by the National Natural Science Foundation of China (Grant No. 31272330) to YFthe National Key Programme of Research and Development, Ministry of Science and Technology (2016YFC0503200) to ZZ
文摘Background:The Emei Shan Liocichla(Liocichla omeiensis) is an endemic bird species to southwestern China with a small geographic range. However, little was known about the genetic status of this threatened species.Methods:We applied restriction-site-associated DNA sequencing(RAD-Seq) for rapid mass identification of microsatellite markers of the Emei Shan Liocichla.Results:A total of 11,564 microsatellite sequences were obtained, 600 random loci were designed for screening and 24 polymorphic microsatellite loci were selected for further validation. The average allele number, average observed heterozygosity and average expected heterozygosity were relatively low in our samples, which were 6.08, 0.6618 and 0.7048, respectively, indicating that the Emei Shan Liocichla might have lost some genetic diversity. Further analyses suggested that the populations distributed on two mountains(Daxiangling and Xiaoliangshan) showed a modest degree of genetic differentiation.Conclusions:These novel microsatellite markers provided valuable preliminary knowledge regarding the genetic status of the Emei Shan Liocichla and can be useful in further studies, as well as in the management and conservation of this species.
基金supported by the National Natural Science Foundation of China(Nos.11075100 and 11565001)the Natural Foundation of Shanxi Province(No.2011011001-2)the Shanxi Provincial Foundation for Returned Overseas Chinese Scholars,China(No.2011-058)
文摘The emission angle distribution of projectile fragments(PFs)and the temperature of PF emission sources for fragmentation of 56Fe on polyethylene,carbon,and aluminum targets at the highest energy of 497 A MeV are investigated on the basis of corrected data,using a CR-39 plastic nuclear track detector.It is found that the average emission angle of PFs increases with the decrease in PF charge for the same target,and no obvious dependence of angular distribution on the mass of the target nucleus is found for the same PF.The cumulative squared transverse momentum distribution of PFs can be well represented by a single Rayleigh distribution.The temperature of PF emission sources is extracted from the distribution,and it is about 1.0-8.0 MeV and does not depend on the mass of the target for PFs with charges of 9≤Z≤25.
基金Supported by National Science Foundation of China(11075100)Natural Science Foundation of Shanxi Province(2011011001-2)the Shanxi Provincial Foundation for Returned Overseas Chinese Scholars,(2011-058)
文摘The multiplicity distribution, multiplicity moment, scaled variance, entropy and reduced entropy of target evaporated fragments emitted in forward and backward hemispheres in 12 A GeV ^4He, 3.7 A GeV ^16O, 60 A GeV ^16O, 1.7 A GeV ^84Kr and 10.7 A GeV ^197Au -induced emulsion heavy target (AgBr) interactions are investigated. It is found that the multiplicity distribution of target evaporated fragments emitted in both forward and backward hemispheres can be fitted by a Gaussian distribution. The multiplicity moments of target evaporated particles emitted in the forward and backward hemispheres increase with the order of the moment q, and the secondorder multiplicity moment is energy independent over the entire energy range for all the interactions in the forward and backward hemisphere. The scaled variance, a direct measure of multiplicity fluctuations, is close to one for all the interactions, which indicate a correlation among the produced particles. The entropy of target evaporated fragments emitted in both forward and backward hemispheres are the same within experimental errors.
基金Project supported by the National Natural Science Foundation of China(Grant Nos 10475054 and 10275042), the Natural Science Foundation of Shanxi Province, China (Grant No 20021007) and the Shanxi Provincial Foundation for Returned Scholars of China (Grant No 20031046).
文摘The topology of ^16 O fragmentation at 3.7 A GeV in reactions with emulsion nuclei is presented. The multiplicity distributions of projectile fragments, charged secondaries and their dependences on the projectile residues are discussed.
文摘Diabetes Mellitus is a chronic disease that affects important body organs in a very serious manner. The consequences of this disease turn out to be a significant problem for the patient, who tries to cope with the new condition his organism has been placed in. The most common effect of the disease, hyperglycaemia, leads over time to serious damage to various body systems, such as nerves and blood vessels. What is not widely known among the population is that diabetes may have harmful effects on the reproductive system of the men suffering from diabetes type 1 and 2 and that such a parameter could lead to or might be the reason for infertility problems for couples, for example, miscarriage or embryonic failure. AGEs is a number of products which are believed to play an important role, because their presence has been detected in increased level in diabetic men. This implies that those glycation products might play a key role in diabetic complications. Their receptor, RAGE, member of the immunoglobulin superfamily has been detected in the reproductive tract of diabetic men. Reactive oxygen species (ROS), a possible product of AGEs appear in high levels in seminal plasma and are believed to be the cause of DNA fragmentation. The objective of this review was to gather all the available material i.e. studies on diabetes mellitus in one article, to study the research which has already been conducted and the conclusions that have been drawn, in order to offer, if possible, new pathways and perspectives to the scientists, who focus on fertility problems, sometimes intractable.
基金①The project supported in part by the National Natural Science Foundation of Chinathe Science Foundation of Chinese Nuclear Industry
文摘We use the bond percolation model to study the multifragrnentation of<sup>197</sup>Au projectiles interact-ing with Cu target at a bombarding energy of 600 MeV/u.The charge observables and some of their dif-ferential distributions are analyzed.The theoretical results agree well with the experimental data ofALADIN collaboration.This indicates that the percolation model can describe reasonably the universal be-havior of nuclear fragmentation in nucleus-nucleus collisions.
基金supported by the National Natural Science Foundation of China (Grant Nos 10475054 and 10675077)the Foundation for Key Program of Ministry of Education of China (Grant No 2 05026)+1 种基金the Natural Science Foundation of Shanxi Province, China(Grant No 200801105)the Shanxi Provincial Foundation for Returned Scholars, China
文摘The properties of the relativistic helium fragments produced in interactions of ^84Kr at 1.8 A GeV and ^197Au at 10.7 A GeV in emulsion are investigated. The experimental results are compared with those obtained from various projectiles with emulsion collisions at different energies. It is found that the multiplicity distribution of helium projectile fragments (HPFs) is well described by the Koba-Nielsen Olesen (KNO) scaling presentation. The second Mueller moment f2 of the HPF multiplicity distribution is independent of the projectile energy for the same projectile, but it is dependent on the projectile mass number. The value of f2 increases with the increase of projectile mass number Ap. The negative value of f2, when Ap 〈 69, means that the emission of HPFs is anticorrelated, but positive value of f2, when Ap 〉 69, refers to that the emission of HPFs is correlated. The non-zero f2 moment in this experiment implies the strong correlation existing between the HPFs.
基金Supported by National Science Foundation of China(11075100)Natural Science Foundation of Shanxi Province,China(20110110012)Shanxi Provincial Foundation for Returned Overseas Chinese Scholars,China(2011-058)
文摘The forward-backward multiplicity and correlations of a target evaporated fragment (black track particle) and target recoiled proton (grey track particle) emitted from 150 A MeV 4He, 290 A MeV ^12C, 400 A MeV ^12C, 400 A MeV ^20Ne and 500 A MeV ^56Fe induced different types of nuclear emulsion target interactions are investigated. It is found that the forward and backward averaged multiplicity of a grey, black and heavily ionized track particle increases with the increase of the target size. The averaged multiplicity of a forward black track particle, backward black track particle, and backward grey track particle do not depend on the projectile size and energy, but the averaged multiplicity of a forward grey track particle increases with an increase of projectile size and energy. The backward grey track particle multiplicity distribution follows an exponential decay law and the decay constant decreases with an increase of target size. The backward-forward multiplicity correlations follow linear law which is independent of the projectile size and energy, and the saturation effect is observed in some heavy target data sets.
基金Supported by National Science Foundation of China(11075100),Natural Science Foundation of Shanxi Province,China(20110110012)Shanxi Provincial Foundation for Returned Overseas Chinese Scholars,China(2011-058)
文摘Multiplicity fluctuation of the target evaporated fragments emitted in 290 MeV/u 12C-AgBr, 400 MeV/u 12C-AgBr, 400 MeV/u 20Ne-AgBr and 500 MeV/u 56Fe-AgBr interactions is investigated using the scaled factorial moment method in two-dimensional normal phase space and cumulative variable space, respectively. It is found that in normal phase space the scaled factorial moment (ln(Fq)) increases linearly with the increase of the divided number of phase space (lnM) for lower q-value and increases linearly with the increase of lnM, and then becomes saturated or decreased for a higher q-value. In cumulative variable space ln(Fq) decreases linearly with increase of lnM. This indicates that no evidence of non-statistical multiplicity fluctuation is observed in our data sets. So, any fluctuation indicated in the results of normal variable space analysis is totally caused by the non-uniformity of the single-particle density distribution.
基金Project supported by the National Natural Science Foundation of China (Grant No. 11075100)Shanxi Scholarship Council of China (Grant No. 2011-058)
文摘The projected angular distribution and transverse momentum distribution of proton projectile fragments produced in 3.7A GeV 160, 500A MeV 56Fe, and 1.7A GeV S4Kr induced by different kinds of emulsion target (H, CNO, and AgBr) interactions are investigated. It is found that the projected angular distribution and transverse momentum distribution can be well represented by a single Gaussian distribution. Comparison of transverse momentum distribution with the Maxwell-Boltzmann distribution reveals that proton projectile fragments are emitted from a single-temperature emission source. The temperature is different for different colliding systems, and linearly depends on the target size.