Short Retraction NoticeThe paper does not meet the standards of "Journal of Applied Mathematics and Physics". This article has been retracted to straighten the academic record. In making this decision the Ed...Short Retraction NoticeThe paper does not meet the standards of "Journal of Applied Mathematics and Physics". This article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of scientific research by offering an ideal research publication platform with due consideration of internationally accepted standards on publication ethics. The Editorial Board would like to extend its sincere apologies for any inconvenience this retraction may have caused.Editor guiding this retraction: Prof. Wen-Xiu Ma (EiC of JAMP)The full retraction notice in PDF is preceding the original paper, which is marked "RETRACTED".展开更多
To compare with the predictions of the transitional dynamical symmetry X(5) proposed by Iachello (2001 Phys. Rev. Lett. 87 052502), the critical behaviours of U(5) SU(3) are studied in the space of two control...To compare with the predictions of the transitional dynamical symmetry X(5) proposed by Iachello (2001 Phys. Rev. Lett. 87 052502), the critical behaviours of U(5) SU(3) are studied in the space of two control parameters in the interacting boson model (IBM). A simple-shaped phased diagram has been presented. It is found that X(5) predictions cannot be exactly reproduced by our calculations and that the best agreement is close to the calculations with boson numbers N = 11 and 12. By comparing with experimental data on X(5)-like nuclei, we find that X(5) predictions and IBM calculations can reproduce the energy ratios and E2 transition ones.展开更多
The number of traditionally excellent coastal lithologic nuclear power plants is limited.It is a trend to develop nuclear power plants on soil sites in inland areas.Therefore,the seismic safety and adaptability of non...The number of traditionally excellent coastal lithologic nuclear power plants is limited.It is a trend to develop nuclear power plants on soil sites in inland areas.Therefore,the seismic safety and adaptability of non-rock nuclear power plant(NPP)sites are the key concerns of nuclear safety researchers.Although the five site categories are clearly defined in the AP1000 design control documents,the effects of nuclear power five site conditions and soil nonlinearity on the seismic response characteristics of nuclear island buildings have not been systematically considered in previous related studies.In this study,targeting the AP1000 nuclear island structure as the research object,three-dimensional finite element models of a nuclear island structure at five types of sites(firm rock site(FR),soft rock site(SR),soft-to-medium soil site(SMS),upper bound soft-to-medium site(SMS-UB),and soft soil site(SS))are established.The partitioned analysis method of soil-structure interaction(PASSI)in the time-domain is used to investigate the effects of site hardness and nonlinearity on the acceleration,displacement,and acceleration response spectrum of the nuclear island structure under seismic excitation.The incremental equilibrium equation and explicit decoupling method are used to analyze the soil nonlinearity described by the Davidenkov model with simplified loading-reloading rules.The results show that,in the linear case,with the increase of site hardness,the peak ground acceleration(PGA)and the peak of acceleration response spectrum of the nuclear island structure increase except for the FR site,while the maximum displacement decreases.In nonlinear analysis,as the site hardness increases,the PGA,maximum displacement,and the peak of acceleration response spectrum of the nuclear island structure increase.The peak value of the acceleration response spectrum in the nonlinear case is greater than that in the linear case for FR,while smaller for SR and soil sites.The site nonlinearity reduces the peak values of the response spectrum for SR and soil sites much more as the site hardness decreases.The results of this study can provide a reference for design of nuclear island structures on soil and rock sites.展开更多
The 12th National Conference on Nuclear Structure and the 8th Symposium on Nuclear Structure, hosted by Southwest University and organized by the Nuclear Structure Committee of the Chinese Nuclear Physics Society, Chi...The 12th National Conference on Nuclear Structure and the 8th Symposium on Nuclear Structure, hosted by Southwest University and organized by the Nuclear Structure Committee of the Chinese Nuclear Physics Society, China Center of Advanced展开更多
Heterogeneous nuclear ribonucleoprotein (hnRNP) C plays a key role in RNA processing but also exerts a dominant negative effect on responses to 1,25-dihydroxyvitamin D (1,25(OH)2D) by functioning as a vitamin D ...Heterogeneous nuclear ribonucleoprotein (hnRNP) C plays a key role in RNA processing but also exerts a dominant negative effect on responses to 1,25-dihydroxyvitamin D (1,25(OH)2D) by functioning as a vitamin D response element-binding protein (VDRE-BP). hnRNPC acts a tetramer of hnRNPC1 (huC1) and hnRNPC2 (huC2), and organization of these subunits is critical to in vivo nucleic acid-binding. Overexpression of either huC1 or huC2 in human osteoblasts is sufficient to confer VDRE-BP suppression of 1,25(OH)2D-mediated transcription. However, huC1 or huC2 alone did not suppress 1,25(OH)2D-induced transcription in mouse osteoblastic cells. By contrast, overexpression of huC1 and huC2 in combination or transfection with a bone-specific polycistronic vector using a "self-cleaving" 2A peptide to co-express huC1/C2 suppressed 1,25D-mediated induction of osteoblast target gene expression. Structural diversity of hnRNPC between human/NWPs and mouse/rat/rabbit/dog was investigated by analysis of sequence variations within the hnRNP CLZ domain. The predicted loss of distal helical function in hnRNPC from lower species provides an explanation for the altered interaction between huC1/C2 and their mouse counterparts. These data provide new evidence of a role for hnRNPC1/C2 in 1,25(OH)2D-driven gene expression, and further suggest that species-specific tetramerization is a crucial determinant of its actions as a regulator of VDR-directed transactivation.展开更多
In this paper we study the structure coeficients of collective pairs with spin zero and spin two (SD) in a number of configurations by a few realistic nuclei. We investigate the robustness of these structure coeffcien...In this paper we study the structure coeficients of collective pairs with spin zero and spin two (SD) in a number of configurations by a few realistic nuclei. We investigate the robustness of these structure coeffcients with respect to different configurations and the evolution of SD-pair structure coeffcients with valence nucleon number.展开更多
Prostate cancer (PCa) results from a multistep process. This process includes initiation, which occurs through various aging events and multiple insults (such as chronic infection, inflammation and genetic instabil...Prostate cancer (PCa) results from a multistep process. This process includes initiation, which occurs through various aging events and multiple insults (such as chronic infection, inflammation and genetic instability through reactive oxygen species causing DNA double-strand breaks), followed by a multistep process of progression. These steps include several genetic and epigenetic alterations, as well as alterations to the chromatin structure, which occur in response to the carcinogenic stress-related events that sustain proliferative signaling. Events such as evading growth suppressors, resisting cell death, enabling replicative immortality, inducing angiogenesis, and activating invasion and metastasis are readily observed. In addition, in conjunction with these critical drivers of carcinogenesis, other factors related to the etiopathogenesis of PCa, involving energy metabolism and evasion of the immune surveillance system, appear to be involved. In addition, when cancer spread and metastasis occur, the 'tumor microenvironment' in the bone of PCa patients may provide a way to sustain dormancy or senescence and eventually establish a 'seed and soil' site where PCa proliferation and growth may occur over time. When PCa is initiated and progression ensues, significant alterations in nuclear size, shape and heterochromatin (DNA transcription) organization are found, and key nuclear transcriptional and structural proteins, as well as multiple nuclear bodies can lead to precancerous and malignant changes. These series of cellular and tissue-related malignancy-associated events can be quantified to assess disease progression and management.展开更多
Constrained spherical Hartree-Fock (CSHF) calculations under radial compression are presented for <sup>90</sup>Zr in a model space consisting of nine major oscillator shells. An effective baryon-baryon int...Constrained spherical Hartree-Fock (CSHF) calculations under radial compression are presented for <sup>90</sup>Zr in a model space consisting of nine major oscillator shells. An effective baryon-baryon interaction which includes the Δ resonances is used. The nucleon-nucleon (N-N) interaction is Reid Soft Core (RSC) potential. The sensitivity of the results to the choice model space is examined. It is found that the nuclear system becomes more compressible when the model space is increased. The radial density and the number of Δs are decreased by increasing model space. The results suggest that the behavior of single particle energies is independent of the model space.展开更多
A more compact representation of the Segré chart of nuclides can be obtained replacing the isotopic neutron with the corresponding neutron excess number;a first sight inspection of all the natural isotopes is pro...A more compact representation of the Segré chart of nuclides can be obtained replacing the isotopic neutron with the corresponding neutron excess number;a first sight inspection of all the natural isotopes is produced. The resulting representation shows a built-inorder in the organization of the nuclear components into the nuclei of the natural isotopes, sustained by the relevant role of the magic numbers. The interpretation, on the identical foot, of the nuclear instability of Tc, Pm and of the elements following Bi is suggested. The present representation reminds the spheron model of the nuclear structure suggested by L. Pauling. The alpha decay paths of radioactive isotopes are shown, side by side to the low energy nuclear transmutations (LENR). Representations of the artificial isotopes of the chemical elements and of the stellar nucleosynthesis processes are also proposed.展开更多
The high-spin states of 141pro nucleus have been studied by using in-beam v-ray spectroscopy technology through the126Te(19F, 4n) reaction at a beam energy of 90 MeV. The previous level scheme has been extended with...The high-spin states of 141pro nucleus have been studied by using in-beam v-ray spectroscopy technology through the126Te(19F, 4n) reaction at a beam energy of 90 MeV. The previous level scheme has been extended with spin up to 49/2 h. Many new levels and transitions are identified. Five collective band structures are observed. Based on systematic comparison with the neighboring nuclei, two bands with strong AI = 1 M1 transitions inside the bands are proposed as the oblate bands with γ--60°, and three bands with large signature splitting have been suggested as the oblate-triaxial deformation with γ--90°. The characteristics for these bands have been discussed.展开更多
An angular momentum projected potential-energy-surface (PES) calculation, which takes both rotational symmetry restoration and multi-quasiparticle excitation into account, is developed by using the macroscopic-micro...An angular momentum projected potential-energy-surface (PES) calculation, which takes both rotational symmetry restoration and multi-quasiparticle excitation into account, is developed by using the macroscopic-microscopic model and the projected shell model (PSM). Within this method, it may become possible to modify the excitation spectra which are influenced by shape-softness of nuclei, including high-K states. As our first example, this method is adopted to study the collective and multi-quasiparticle excitations of 178Hf~ and the results are in good agreement with the existing experimental data. In addition, as for the dominant structure of non- collective 6+ bands, the conflict between experimental result and the previous PSM calculation is clarified.展开更多
Recently an algorithm that acts the variational principle directly to a coherent-pair condensate (VDPC) has been proposed. This algorithm can avoid time-consuming projection while maintaining particle number conservat...Recently an algorithm that acts the variational principle directly to a coherent-pair condensate (VDPC) has been proposed. This algorithm can avoid time-consuming projection while maintaining particle number conservation. Quickly computation of many-pair density matrix (MPDM) is one of the keys to improve the computational efficiency of VDPC algorithm. In this work, we propose a scheme that limits the energy range of block particles to the vicinity of the Fermi surface, which reduces the time complexity of computing the MPDM without losing physical details. The results show that by appropriately limiting the energy range, we can greatly reduce the number of matrix elements that need to be computed, and reducing the time required for the computation.展开更多
Extended quark distribution functions are presented obtained by fitting a large amount of experimental data of the l-A DIS process on the basis of an improved nuclear density model. The experimental data of l-A DIS pr...Extended quark distribution functions are presented obtained by fitting a large amount of experimental data of the l-A DIS process on the basis of an improved nuclear density model. The experimental data of l-A DIS processes with A≥ 3 in the region 0.0010 ≤ x ≤ 0.9500 are quite satisfactorily described by using the extended formulae. Our knowledge of the influence of nuclear matter on the quark distributions is deepened.展开更多
Molecular dynamics simulations are performed with the recently developed empirical interaction potential by Morelon et al. Thermodynamics properties of solid UO2 that have been assessed include melt point, density, en...Molecular dynamics simulations are performed with the recently developed empirical interaction potential by Morelon et al. Thermodynamics properties of solid UO2 that have been assessed include melt point, density, enthalpy, heat capacity, lattice parameter variation with temperature, mean-square-displacement and diffusion coefficients of oxygen ion. The results are compared with the data in literature and it is suggested that the rigid ionic potential provides perfect results below the superionic range. The data showing thermodynamics properties will become unacceptable when the temperature is higher than 2500 K. Compared with the previous empirical potentials, the empirical potential developed by Morelon et al. improves the agreement of these data with the recommend ones.展开更多
This paper presents the NUBASE2016 evaluation that contains the recommended values for nuclear and decay properties of 3437 nuclides in their ground and excited isomeric (T1/2〉 100 ns) states. All nuclides for whic...This paper presents the NUBASE2016 evaluation that contains the recommended values for nuclear and decay properties of 3437 nuclides in their ground and excited isomeric (T1/2〉 100 ns) states. All nuclides for which any experimental information is known were considered. NUSASE2016 covers all data published by October 2016 in primary (journal articles) and secondary (mainly laboratory reports and conference proceedings) references, together with the corresponding bibliographical information. During the development of NUBASE2016, the data available in the "Evaluated Nuclear Structure Data File" (ENSDF) database were consulted and critically assessed for their validity and completeness. Furthermore, a large amount of new data and some older experimental results that were missing from ENSDF were compiled, evaluated and included in NUBASE2016. The atomic mass values were taken from the "Atomic Mass Evaluation" (AME2016, second and third parts of the present issue). In cases where no experimental data were available for a particular nuclide, trends in the behavior of specific properties in neighboring nuclides (TNN) were examined. This approach allowed to estimate values for a range of properties that are labeled in NUBASE2016 as "non-experimental" (flagged "#"). Evaluation procedures and policies used during the development of this database are presented, together with a detailed table of recommended values and their uncertainties.展开更多
We discuss cluster phenomena in light nuclei. As examples of typical cluster structures, we first review cluster structures of 12C, 16O, and 20Ne, and then introduce some topics of cluster phenomena in light neutron-r...We discuss cluster phenomena in light nuclei. As examples of typical cluster structures, we first review cluster structures of 12C, 16O, and 20Ne, and then introduce some topics of cluster phenomena in light neutron-rich nuclei such as Be and C isotopes. A particular attention is paid on coexistence of cluster and shell-model aspects.展开更多
The Shanghai Laser Electron Gamma Source(SLEGS, located in BL03SSID) beamline at the Shanghai Synchrotron Radiation Facility(SSRF) is a Laser Compton Scattering(LCS) gamma source used for the investigation of nuclear ...The Shanghai Laser Electron Gamma Source(SLEGS, located in BL03SSID) beamline at the Shanghai Synchrotron Radiation Facility(SSRF) is a Laser Compton Scattering(LCS) gamma source used for the investigation of nuclear structure, which is in extensive demand in fields such as nuclear astrophysics, nuclear cluster structure, polarization physics, and nuclear energy. The beamline is based on the inverse Compton scattering of 10640 nm photons on 3.5 GeV electrons and a gamma source with variable energy by changing the scattering angle from 20° to 160°. γ rays of 0.25-21.1 MeV can be extracted by the scheme consisting of the interaction chamber, coarse collimator, fine collimator, and attenuator. The maximum photon flux for 180° is approximately 10~7 photons/s at the target at 21.7 MeV, with a 3-mm-diameter beam. The beamline was equipped with four types of spectrometers for experiments in( γ,γ'),( γ,n),( γ,p), and( γ,α). At present, Nuclear Resonance Fluorescence(NRF) spectrometry, Flat-Efficiency neutron Detector(FED) spectrometry, neutron Time-Of-Flight(TOF) spectrometry, and Light-Charged Particle(LCP) spectrometry methods have been developed.展开更多
The structures of the neutron deficient Nd isotopes of A=128~140 are studied in a schematic hamiltonian in the interacting boson model. The level structure and E2 transitions can be well described in the sch...The structures of the neutron deficient Nd isotopes of A=128~140 are studied in a schematic hamiltonian in the interacting boson model. The level structure and E2 transitions can be well described in the scheme. In particular, the backbending in the ground state band is well reproduced.展开更多
The paper includes discussions on the important role of neutron and alpha configurations in proton-rich nuclei in nuclear astrophysics in terms of nucleosynthesis under extremely high-temperature hydrogenburning condi...The paper includes discussions on the important role of neutron and alpha configurations in proton-rich nuclei in nuclear astrophysics in terms of nucleosynthesis under extremely high-temperature hydrogenburning conditions. The νp-process, which is supposed to take place at the very early epoch of type II supernovae, has considerable neutrons and alphas together with protons. The alpha-induced reactions on proton-rich unstable nuclei in the light mass regions is expected to play a crucial role, but very few of them were investigated well yet because of the experimental difficulties. Specifically, I report our recent experimental effort for the breakout process from the pp-chain region,~7Be(α, γ)^(11)C(α,p)^(14)N under the νp-process. The neutron-induced reactions on proton-rich nuclei, which is even more a challenging subject, were investigated previously for very few nuclei. One possible experimental method is the Trojan Horse Method(THM). We successfully have applied THM to the ^(18)F(n,α)^(14)N reaction study with an unstable beam of ^(18)F.展开更多
In relativistic heavy ion collisions,the fluctuations of initial entropy density convert to the correlations of final state hadrons in momentum space through the collective expansion of strongly interacting QCD matter...In relativistic heavy ion collisions,the fluctuations of initial entropy density convert to the correlations of final state hadrons in momentum space through the collective expansion of strongly interacting QCD matter.Using a(3+1)D viscous hydrodynamic program,CL Visc,we consider whether the nuclear structure,which provides initial state fluctuations as well as correlations,can affect the final state of heavy ion collisions,and whether one can find signals of α cluster structures in oxygen using final state observables in ^(16)O+ ^(16)O collisions at the CERN Large Hadron Collider.For the initial nucleon distributions in oxygen nuclei,we compare three different configurations,a tetrahedral structure with four-α clusters,the deformed Woods-Saxon distribution,and a spherical symmetric Woods-Saxon distribution.Our results show that the charged multiplicity as a function of centrality and the elliptic flow at the most central collisions using the four-α structure differs from those with the Woods-Saxon and deformed Woods-Saxon distributions,which may help to identify α clustering structures in oxygen nuclei.展开更多
文摘Short Retraction NoticeThe paper does not meet the standards of "Journal of Applied Mathematics and Physics". This article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of scientific research by offering an ideal research publication platform with due consideration of internationally accepted standards on publication ethics. The Editorial Board would like to extend its sincere apologies for any inconvenience this retraction may have caused.Editor guiding this retraction: Prof. Wen-Xiu Ma (EiC of JAMP)The full retraction notice in PDF is preceding the original paper, which is marked "RETRACTED".
基金Project supported in part by the National Natural Science Foundation of China (Grant Nos 10265001 and 10547003), the Natural Science Foundation of Inner Mongolian, China (Grant No 200607010111), and Chifeng College Scientific Research Fund of China (Grant No ZRZD200604). Acknowledgement The authors are greatly indebted to Professor Long G L for his continuing interest in this work and his many suggestions.
文摘To compare with the predictions of the transitional dynamical symmetry X(5) proposed by Iachello (2001 Phys. Rev. Lett. 87 052502), the critical behaviours of U(5) SU(3) are studied in the space of two control parameters in the interacting boson model (IBM). A simple-shaped phased diagram has been presented. It is found that X(5) predictions cannot be exactly reproduced by our calculations and that the best agreement is close to the calculations with boson numbers N = 11 and 12. By comparing with experimental data on X(5)-like nuclei, we find that X(5) predictions and IBM calculations can reproduce the energy ratios and E2 transition ones.
基金National Natural Science Foundation of China under Grant Nos.51978337 and U2039209。
文摘The number of traditionally excellent coastal lithologic nuclear power plants is limited.It is a trend to develop nuclear power plants on soil sites in inland areas.Therefore,the seismic safety and adaptability of non-rock nuclear power plant(NPP)sites are the key concerns of nuclear safety researchers.Although the five site categories are clearly defined in the AP1000 design control documents,the effects of nuclear power five site conditions and soil nonlinearity on the seismic response characteristics of nuclear island buildings have not been systematically considered in previous related studies.In this study,targeting the AP1000 nuclear island structure as the research object,three-dimensional finite element models of a nuclear island structure at five types of sites(firm rock site(FR),soft rock site(SR),soft-to-medium soil site(SMS),upper bound soft-to-medium site(SMS-UB),and soft soil site(SS))are established.The partitioned analysis method of soil-structure interaction(PASSI)in the time-domain is used to investigate the effects of site hardness and nonlinearity on the acceleration,displacement,and acceleration response spectrum of the nuclear island structure under seismic excitation.The incremental equilibrium equation and explicit decoupling method are used to analyze the soil nonlinearity described by the Davidenkov model with simplified loading-reloading rules.The results show that,in the linear case,with the increase of site hardness,the peak ground acceleration(PGA)and the peak of acceleration response spectrum of the nuclear island structure increase except for the FR site,while the maximum displacement decreases.In nonlinear analysis,as the site hardness increases,the PGA,maximum displacement,and the peak of acceleration response spectrum of the nuclear island structure increase.The peak value of the acceleration response spectrum in the nonlinear case is greater than that in the linear case for FR,while smaller for SR and soil sites.The site nonlinearity reduces the peak values of the response spectrum for SR and soil sites much more as the site hardness decreases.The results of this study can provide a reference for design of nuclear island structures on soil and rock sites.
文摘The 12th National Conference on Nuclear Structure and the 8th Symposium on Nuclear Structure, hosted by Southwest University and organized by the Nuclear Structure Committee of the Chinese Nuclear Physics Society, China Center of Advanced
基金supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health under Award Number 5R01AR037399the UCLA Vector Core (Emmanuelle Faure and Kip Hermann) for vector and viral preparations supported by JCCC/P30 CA016042 and CURE/P30 DK41301
文摘Heterogeneous nuclear ribonucleoprotein (hnRNP) C plays a key role in RNA processing but also exerts a dominant negative effect on responses to 1,25-dihydroxyvitamin D (1,25(OH)2D) by functioning as a vitamin D response element-binding protein (VDRE-BP). hnRNPC acts a tetramer of hnRNPC1 (huC1) and hnRNPC2 (huC2), and organization of these subunits is critical to in vivo nucleic acid-binding. Overexpression of either huC1 or huC2 in human osteoblasts is sufficient to confer VDRE-BP suppression of 1,25(OH)2D-mediated transcription. However, huC1 or huC2 alone did not suppress 1,25(OH)2D-induced transcription in mouse osteoblastic cells. By contrast, overexpression of huC1 and huC2 in combination or transfection with a bone-specific polycistronic vector using a "self-cleaving" 2A peptide to co-express huC1/C2 suppressed 1,25D-mediated induction of osteoblast target gene expression. Structural diversity of hnRNPC between human/NWPs and mouse/rat/rabbit/dog was investigated by analysis of sequence variations within the hnRNP CLZ domain. The predicted loss of distal helical function in hnRNPC from lower species provides an explanation for the altered interaction between huC1/C2 and their mouse counterparts. These data provide new evidence of a role for hnRNPC1/C2 in 1,25(OH)2D-driven gene expression, and further suggest that species-specific tetramerization is a crucial determinant of its actions as a regulator of VDR-directed transactivation.
基金the National Natural Science Foundation of China (Grant No.10675081) for supporting this worksupported partlyby the Research Foundation for Doctoral Program of Higher Education inChina (Grant No. 20060248050)+1 种基金the Scientific Research Foundation of Min-istry of Education in China for Returned Scholars (Grant No. NCET-07-0557)the Chinese Major State Basic Research Developing Program(Grant No. 2007CB815000)
文摘In this paper we study the structure coeficients of collective pairs with spin zero and spin two (SD) in a number of configurations by a few realistic nuclei. We investigate the robustness of these structure coeffcients with respect to different configurations and the evolution of SD-pair structure coeffcients with valence nucleon number.
文摘Prostate cancer (PCa) results from a multistep process. This process includes initiation, which occurs through various aging events and multiple insults (such as chronic infection, inflammation and genetic instability through reactive oxygen species causing DNA double-strand breaks), followed by a multistep process of progression. These steps include several genetic and epigenetic alterations, as well as alterations to the chromatin structure, which occur in response to the carcinogenic stress-related events that sustain proliferative signaling. Events such as evading growth suppressors, resisting cell death, enabling replicative immortality, inducing angiogenesis, and activating invasion and metastasis are readily observed. In addition, in conjunction with these critical drivers of carcinogenesis, other factors related to the etiopathogenesis of PCa, involving energy metabolism and evasion of the immune surveillance system, appear to be involved. In addition, when cancer spread and metastasis occur, the 'tumor microenvironment' in the bone of PCa patients may provide a way to sustain dormancy or senescence and eventually establish a 'seed and soil' site where PCa proliferation and growth may occur over time. When PCa is initiated and progression ensues, significant alterations in nuclear size, shape and heterochromatin (DNA transcription) organization are found, and key nuclear transcriptional and structural proteins, as well as multiple nuclear bodies can lead to precancerous and malignant changes. These series of cellular and tissue-related malignancy-associated events can be quantified to assess disease progression and management.
文摘Constrained spherical Hartree-Fock (CSHF) calculations under radial compression are presented for <sup>90</sup>Zr in a model space consisting of nine major oscillator shells. An effective baryon-baryon interaction which includes the Δ resonances is used. The nucleon-nucleon (N-N) interaction is Reid Soft Core (RSC) potential. The sensitivity of the results to the choice model space is examined. It is found that the nuclear system becomes more compressible when the model space is increased. The radial density and the number of Δs are decreased by increasing model space. The results suggest that the behavior of single particle energies is independent of the model space.
文摘A more compact representation of the Segré chart of nuclides can be obtained replacing the isotopic neutron with the corresponding neutron excess number;a first sight inspection of all the natural isotopes is produced. The resulting representation shows a built-inorder in the organization of the nuclear components into the nuclei of the natural isotopes, sustained by the relevant role of the magic numbers. The interpretation, on the identical foot, of the nuclear instability of Tc, Pm and of the elements following Bi is suggested. The present representation reminds the spheron model of the nuclear structure suggested by L. Pauling. The alpha decay paths of radioactive isotopes are shown, side by side to the low energy nuclear transmutations (LENR). Representations of the artificial isotopes of the chemical elements and of the stellar nucleosynthesis processes are also proposed.
基金supported by National Natural Science Foundation of China (Nos. 10975082, 10775078)the Major State Basic Research Development Program of China (No. 2007CB815005)the Special Program of Higher Education Science Foundation of China (No. 20070003149)
文摘The high-spin states of 141pro nucleus have been studied by using in-beam v-ray spectroscopy technology through the126Te(19F, 4n) reaction at a beam energy of 90 MeV. The previous level scheme has been extended with spin up to 49/2 h. Many new levels and transitions are identified. Five collective band structures are observed. Based on systematic comparison with the neighboring nuclei, two bands with strong AI = 1 M1 transitions inside the bands are proposed as the oblate bands with γ--60°, and three bands with large signature splitting have been suggested as the oblate-triaxial deformation with γ--90°. The characteristics for these bands have been discussed.
基金supported by Natural Science Foundation of China (Nos. 10735010, 10975006)the Chinese Major State Basic Research Development Program (No. 2007CB815000)
文摘An angular momentum projected potential-energy-surface (PES) calculation, which takes both rotational symmetry restoration and multi-quasiparticle excitation into account, is developed by using the macroscopic-microscopic model and the projected shell model (PSM). Within this method, it may become possible to modify the excitation spectra which are influenced by shape-softness of nuclei, including high-K states. As our first example, this method is adopted to study the collective and multi-quasiparticle excitations of 178Hf~ and the results are in good agreement with the existing experimental data. In addition, as for the dominant structure of non- collective 6+ bands, the conflict between experimental result and the previous PSM calculation is clarified.
文摘Recently an algorithm that acts the variational principle directly to a coherent-pair condensate (VDPC) has been proposed. This algorithm can avoid time-consuming projection while maintaining particle number conservation. Quickly computation of many-pair density matrix (MPDM) is one of the keys to improve the computational efficiency of VDPC algorithm. In this work, we propose a scheme that limits the energy range of block particles to the vicinity of the Fermi surface, which reduces the time complexity of computing the MPDM without losing physical details. The results show that by appropriately limiting the energy range, we can greatly reduce the number of matrix elements that need to be computed, and reducing the time required for the computation.
基金Supported by Natural Science Foundation of China (100775061, 10505016, 10575119)CAS Knowledge Innovation Project(KJCX-SYW-N02)+1 种基金Major State Basic Research Developing Program of China (2007CB815004)Natural Science Foundationof Hebei Province in China (A2005000535, 103143)
文摘Extended quark distribution functions are presented obtained by fitting a large amount of experimental data of the l-A DIS process on the basis of an improved nuclear density model. The experimental data of l-A DIS processes with A≥ 3 in the region 0.0010 ≤ x ≤ 0.9500 are quite satisfactorily described by using the extended formulae. Our knowledge of the influence of nuclear matter on the quark distributions is deepened.
文摘Molecular dynamics simulations are performed with the recently developed empirical interaction potential by Morelon et al. Thermodynamics properties of solid UO2 that have been assessed include melt point, density, enthalpy, heat capacity, lattice parameter variation with temperature, mean-square-displacement and diffusion coefficients of oxygen ion. The results are compared with the data in literature and it is suggested that the rigid ionic potential provides perfect results below the superionic range. The data showing thermodynamics properties will become unacceptable when the temperature is higher than 2500 K. Compared with the previous empirical potentials, the empirical potential developed by Morelon et al. improves the agreement of these data with the recommend ones.
基金This work has been undertaken with the efidorsement of the IUPAP Commission on Symbols, Units, Nomenclature, Atomic Masses and Fundamental Constants (SUNAMCO).
文摘This paper presents the NUBASE2016 evaluation that contains the recommended values for nuclear and decay properties of 3437 nuclides in their ground and excited isomeric (T1/2〉 100 ns) states. All nuclides for which any experimental information is known were considered. NUSASE2016 covers all data published by October 2016 in primary (journal articles) and secondary (mainly laboratory reports and conference proceedings) references, together with the corresponding bibliographical information. During the development of NUBASE2016, the data available in the "Evaluated Nuclear Structure Data File" (ENSDF) database were consulted and critically assessed for their validity and completeness. Furthermore, a large amount of new data and some older experimental results that were missing from ENSDF were compiled, evaluated and included in NUBASE2016. The atomic mass values were taken from the "Atomic Mass Evaluation" (AME2016, second and third parts of the present issue). In cases where no experimental data were available for a particular nuclide, trends in the behavior of specific properties in neighboring nuclides (TNN) were examined. This approach allowed to estimate values for a range of properties that are labeled in NUBASE2016 as "non-experimental" (flagged "#"). Evaluation procedures and policies used during the development of this database are presented, together with a detailed table of recommended values and their uncertainties.
文摘We discuss cluster phenomena in light nuclei. As examples of typical cluster structures, we first review cluster structures of 12C, 16O, and 20Ne, and then introduce some topics of cluster phenomena in light neutron-rich nuclei such as Be and C isotopes. A particular attention is paid on coexistence of cluster and shell-model aspects.
文摘The Shanghai Laser Electron Gamma Source(SLEGS, located in BL03SSID) beamline at the Shanghai Synchrotron Radiation Facility(SSRF) is a Laser Compton Scattering(LCS) gamma source used for the investigation of nuclear structure, which is in extensive demand in fields such as nuclear astrophysics, nuclear cluster structure, polarization physics, and nuclear energy. The beamline is based on the inverse Compton scattering of 10640 nm photons on 3.5 GeV electrons and a gamma source with variable energy by changing the scattering angle from 20° to 160°. γ rays of 0.25-21.1 MeV can be extracted by the scheme consisting of the interaction chamber, coarse collimator, fine collimator, and attenuator. The maximum photon flux for 180° is approximately 10~7 photons/s at the target at 21.7 MeV, with a 3-mm-diameter beam. The beamline was equipped with four types of spectrometers for experiments in( γ,γ'),( γ,n),( γ,p), and( γ,α). At present, Nuclear Resonance Fluorescence(NRF) spectrometry, Flat-Efficiency neutron Detector(FED) spectrometry, neutron Time-Of-Flight(TOF) spectrometry, and Light-Charged Particle(LCP) spectrometry methods have been developed.
基金Supported by the National Natural Scie-nce Foundation of China and the Nuclear
文摘The structures of the neutron deficient Nd isotopes of A=128~140 are studied in a schematic hamiltonian in the interacting boson model. The level structure and E2 transitions can be well described in the scheme. In particular, the backbending in the ground state band is well reproduced.
基金Japan Society for the Promotion of Science(JSPS)Research(KAKENHI)(26287058)
文摘The paper includes discussions on the important role of neutron and alpha configurations in proton-rich nuclei in nuclear astrophysics in terms of nucleosynthesis under extremely high-temperature hydrogenburning conditions. The νp-process, which is supposed to take place at the very early epoch of type II supernovae, has considerable neutrons and alphas together with protons. The alpha-induced reactions on proton-rich unstable nuclei in the light mass regions is expected to play a crucial role, but very few of them were investigated well yet because of the experimental difficulties. Specifically, I report our recent experimental effort for the breakout process from the pp-chain region,~7Be(α, γ)^(11)C(α,p)^(14)N under the νp-process. The neutron-induced reactions on proton-rich nuclei, which is even more a challenging subject, were investigated previously for very few nuclei. One possible experimental method is the Trojan Horse Method(THM). We successfully have applied THM to the ^(18)F(n,α)^(14)N reaction study with an unstable beam of ^(18)F.
基金Supported in part by the National Natural Science Foundation of China (12075098, 12147101, 11875066, 11861131009)Computations Were Performed at the Nuclear Science Computer Center at the CCNU (NSC3)。
文摘In relativistic heavy ion collisions,the fluctuations of initial entropy density convert to the correlations of final state hadrons in momentum space through the collective expansion of strongly interacting QCD matter.Using a(3+1)D viscous hydrodynamic program,CL Visc,we consider whether the nuclear structure,which provides initial state fluctuations as well as correlations,can affect the final state of heavy ion collisions,and whether one can find signals of α cluster structures in oxygen using final state observables in ^(16)O+ ^(16)O collisions at the CERN Large Hadron Collider.For the initial nucleon distributions in oxygen nuclei,we compare three different configurations,a tetrahedral structure with four-α clusters,the deformed Woods-Saxon distribution,and a spherical symmetric Woods-Saxon distribution.Our results show that the charged multiplicity as a function of centrality and the elliptic flow at the most central collisions using the four-α structure differs from those with the Woods-Saxon and deformed Woods-Saxon distributions,which may help to identify α clustering structures in oxygen nuclei.