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1.
Phys Rev Lett ; 133(7): 072502, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39213578

RESUMO

Excited states in ^{10}B were populated with the ^{10}B(p,p^{'}γ)^{10}B^{*} reaction at 8.5 MeV and their γ decay was investigated via coincidence γ-ray spectroscopy. The emitted γ rays were measured using large-volume LaBr_{3}:Ce and CeBr_{3} detectors placed in anti-Compton shields. This allowed the observation of weak γ-ray transitions, such as the M3 transition between the J^{π},T=0^{+},1 isobaric analog state (IAS) and the J^{π},T=3^{+},0 ground state and the E2 transition between the J^{π},T=2_{1}^{+},0 state and the IAS, i.e., performing measurements of branching ratios at the level of λ≥10^{-4}. For the first time in ^{10}B, the competing M1 and M3 transitions from the decay of the IAS have been observed in a γ spectroscopy experiment. The experimental results are compared with ab initio no-core shell model calculation using the newest version of the local position-space chiral N^{3}LO nucleon-nucleon interaction. The calculations reproduce correctly the ordering of the bound states in ^{10}B, and are in reasonable agreement with the observed branching ratios and reduced transition probabilities.

2.
Phys Rev Lett ; 130(19): 192501, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37243656

RESUMO

Using a novel method of isochronous mass spectrometry, the masses of ^{62}Ge, ^{64}As, ^{66}Se, and ^{70}Kr are measured for the first time, and the masses of ^{58}Zn, ^{61}Ga, ^{63}Ge, ^{65}As, ^{67}Se, ^{71}Kr, and ^{75}Sr are redetermined with improved accuracy. The new masses allow us to derive residual proton-neutron interactions (δV_{pn}) in the N=Z nuclei, which are found to decrease (increase) with increasing mass A for even-even (odd-odd) nuclei beyond Z=28. This bifurcation of δV_{pn} cannot be reproduced by the available mass models, nor is it consistent with expectations of a pseudo-SU(4) symmetry restoration in the fp shell. We performed ab initio calculations with a chiral three-nucleon force (3NF) included, which indicate the enhancement of the T=1 pn pairing over the T=0 pn pairing in this mass region, leading to the opposite evolving trends of δV_{pn} in even-even and odd-odd nuclei.

3.
Phys Rev Lett ; 131(24): 242501, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38181133

RESUMO

We report here the first observation of the 0_{2}^{+} state of ^{8}He, which has been predicted to feature the condensatelike α+^{2}n+^{2}n cluster structure. We show that this state is characterized by a spin parity of 0^{+}, a large isoscalar monopole transition strength, and the emission of a strongly correlated neutron pair, in line with theoretical predictions. Our finding is further supported by the state-of-the-art microscopic α+4n model calculations. The present results may lead to new insights into clustering in neutron-rich nuclear systems and the pair correlation and condensation in quantum many-body systems under strong interactions.

4.
J Appl Microbiol ; 130(2): 592-603, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32026569

RESUMO

AIMS: Diseases caused by pathogenic fungi was a major constrain in increasing productivity and improving quality of Panax notoginseng. The aim of this research was to evaluate the inhibitory activity of essential oils (EOs) from Asteraceae family, Chrysanthemum indicum and Laggera pterodonta, against pathogenic fungi of P. notoginseng. METHODS AND RESULTS: The antifungal activity was investigated using multiple methods, disclosing that the EOs from C. indicum and L. pterodonta are active against hypha growth of different fungi but with different degrees of potency. Checkerboard testing indicated that the combination of EOs with hymexazol had synergistic effect against Pythium aphanidermatum, and exhibited additive effects against bulk of targeted pathogenic fungi. Besides, we found that the baseline sensitivity of Fusarium oxysporum to L. pterodonta EOs was higher than those of C. indicum by means of mycelium growth rate method. Finally, the practicability of those EOs as plant pesticide was confirmed by in vivo model showing that EOs can significantly inhibit the occurrence of root rot of P. notoginseng caused by F. oxysporum. CONCLUSION: Those studies suggest that the EOs from C. indicum and L. pterodonta had the potential to develop into new pollution-free pesticides for the protection of precious Chinese herbal medicines. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provided a new way of biological control for overcoming the frequent diseases occurrence of P. notoginseng.


Assuntos
Asteraceae/química , Fungos/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Óleos Voláteis/farmacologia , Panax notoginseng/microbiologia , Asteraceae/classificação , Sinergismo Farmacológico , Fungos/classificação , Fungos/crescimento & desenvolvimento , Hifas/classificação , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Oxazóis/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Óleos de Plantas/farmacologia
5.
Phys Rev Lett ; 125(19): 192505, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33216598

RESUMO

Mass-separated ^{187}Ta_{114} in a high-spin isomeric state has been produced for the first time by multinucleon transfer reactions, employing an argon gas-stopping cell and laser ionization. Internal γ rays revealed a T_{1/2}=7.3±0.9 s isomer at 1778±1 keV, which decays through a rotational band with perturbations associated with the approach to a prolate-oblate shape transition. Model calculations show less influence from triaxiality compared to heavier elements in the same mass region. The isomer-decay reduced E2 hindrance factor f_{ν}=27±1 supports the interpretation that axial symmetry is approximately conserved.

7.
Phys Rev Lett ; 124(22): 222501, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32567911

RESUMO

Here we present new information on the shape evolution of the very neutron-rich ^{92,94}Se nuclei from an isomer-decay spectroscopy experiment at the Radioactive Isotope Beam Factory at RIKEN. High-resolution germanium detectors were used to identify delayed γ rays emitted following the decay of their isomers. New transitions are reported extending the previously known level schemes. The isomeric levels are interpreted as originating from high-K quasineutron states with an oblate deformation of ß∼0.25, with the high-K state in ^{94}Se being metastable and K hindered. Following this, ^{94}Se is the lowest-mass neutron-rich nucleus known to date with such a substantial K hindrance. Furthermore, it is the first observation of an oblate K isomer in a deformed nucleus. This opens up the possibility for a new region of K isomers at low Z and at oblate deformation, involving the same neutron orbitals as the prolate orbitals within the classic Z∼72 deformed hafnium region. From an interpretation of the level scheme guided by theoretical calculations, an oblate deformation is also suggested for the ^{94}Se_{60} ground-state band.

8.
Zhonghua Wai Ke Za Zhi ; 58(2): 91-94, 2020 Feb 01.
Artigo em Chinês | MEDLINE | ID: mdl-32074805

RESUMO

Real-world study is increasingly becoming an important source of evidence for changing clinical practice, especially for clinical problems that can't be randomized. In recent years, real-world research in the field of breast cancer has gradually became a boom. Existing research results have begun to assist in the epidemiological analysis of breast cancer, promote the approval of rare diseases diagnosis and indication, and promote the analysis of real-world treatment status and evaluation of curative effects. Chinese scholars have also established databases and carried out relevant real-world research, providing real-world evidence for clinical practice in China. But domestic research is still in its infancy. The number of real-world research literature published by domestic scholars is relatively small, and there is a lack of pragmatic randomized clinical trial and real-world research for decision-making. In the future, we need to take advantage of the abundant diagnosis and treatment resources, further improve the database, and carry out real-world study on drug development based on population data in China.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , China , Tomada de Decisões , Humanos
9.
Zhonghua Wai Ke Za Zhi ; 57(2): 85-87, 2019 Feb 01.
Artigo em Chinês | MEDLINE | ID: mdl-30704208

RESUMO

Artificial intelligence clinical decision-support system is an important direction of artificial intelligence in the medical field. Both international and domestic researchers are exploring the application value of intelligent decision-making system in the field of cancer. But at the same time of the craze, there are still some problems in the intelligent decision-making system. Combining the work of the research groups in this field, this paper explores the current confusions and solutions, and hopes to help clinicians better understand intelligent decision-making. It is believed that with the deepening of the concept and the advancement of technology, intelligent decision-making will become a good help for doctors in the future.


Assuntos
Inteligência Artificial , Sistemas de Apoio a Decisões Clínicas , Neoplasias , Humanos
10.
Zhonghua Yi Xue Za Zhi ; 98(16): 1231-1235, 2018 Apr 24.
Artigo em Chinês | MEDLINE | ID: mdl-29747310

RESUMO

Objective: To explore the efficacy and safety of polyethylene glycal recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF) in preventing chemotherapy-induced neutropenia in patiens with breast cancer. Methods: There were two parts in the present phase Ⅳ clinical study. One was a randomized, controlled clinical study. Patients in this study received PEG-rhG-CSF or rhG-CSF in the first cycle and followed with both PEG-rhG-CSF in the rest of 3 cycles. The other one was a single arm study. Patients who developed Ⅲ/Ⅳ grade neutropenia in the screening cycle received PEG-rhG-CSF in the rest of 3 cycles chemotherapy. Results: In the first cycle of randomized, controlled study, the incidence of Ⅳ grade neutropenia are 31.48% and 35.58% respectively in PEG-rhG-CSF and rhG-CSF group, with no statistically significant differences (P=0.527 6). The duration of Ⅳ grade neutropenia respectively are 2.22±1.58 and 3.00±1.59 days, with a statistically significant difference (P=0.016 6). In the single arm study, the incidence of Ⅳ grade neutropenia was 57.76% in screening cycle. And the incidence decreased to 16.35%, 10%, and 8.57% in the followed 3 cycle after the use of PEG-rhG-CSF. The incidence of adverse effects was 5.06%, and the major adverse effect was bone pain which with an incidence of 2.8%. Conclusion: The fixed 6mg dose of PEG-rhG-CSF can effectively prevent neutropenia in patients with breast cancer in multicycle chemotherapy and it has a low incidence of adverse events and mild adverse reaction.


Assuntos
Neutropenia/induzido quimicamente , Neoplasias da Mama , Fator Estimulador de Colônias de Granulócitos , Humanos , Neoplasias Pulmonares , Polietileno , Proteínas Recombinantes
11.
Zhonghua Yi Xue Za Zhi ; 98(4): 244-247, 2018 Jan 23.
Artigo em Chinês | MEDLINE | ID: mdl-29397609
12.
Zhonghua Yi Xue Za Zhi ; 97(30): 2349-2352, 2017 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-28822452

RESUMO

Obiective: To explorethe correlation between Neo-Bioscore and disease-free survival (DFS) after neoadjuvant therapy in patients with breast cancer in China. Methods: The clinical and pathological data of 429 patients with early or locally advanced breast cancer who received neoadjuvant therapy at the No.307 Hospital of PLA from January 1, 2005 to December 31, 2015 were analyzed and we followed up their DFS. Results: Neo-Bioscore were closely related to DFS (χ(2)=47.662, P<0.001). When the groups were divided by Neo-Bioscore 3, they weremore relevantto DFS (HR=5.093 vs HR=2.044), equivalent tothe role of traditional recurrence risk grouping in guiding the choice of adjuvantendocrine regimen for hormone receptor (HR) positive patients who were premenopausalafter neoadjuvant chemotherapy, andmore relevantto DFS than whetherthe pathologic complete response (pCR)grouping in the same molecular pathology subgroup of HR positive/human epidermal growth factor receptor 2 (HER-2)negative (P<0.001 vs P=0.166), HER-2 positive (P<0.001 vs P=0.166), HRnegative/HER-2 negative (P<0.001 vs P=0.166). Conclusions: Neo-Bioscore could be used as an early indicator of predicting DFS for breast cancer patients after neoadjuvant therapy.When the groups were divided by Neo-Bioscore 3, they were more relevant to DFS, equivalent to the role of traditional recurrence risk grouping in guiding the choice of adjuvantendocrine regimen for premenopausal HR positive patients, andmore relevantto DFS than whetherthe pCRgrouping in the same molecular pathology subgroup.


Assuntos
Neoplasias da Mama , Terapia Neoadjuvante , Protocolos de Quimioterapia Combinada Antineoplásica , Quimioterapia Adjuvante , China , Intervalo Livre de Doença , Feminino , Humanos , Intervalo Livre de Progressão , Receptor ErbB-2
14.
Zhonghua Wai Ke Za Zhi ; 55(2): 90-94, 2017 Feb 01.
Artigo em Chinês | MEDLINE | ID: mdl-28162205

RESUMO

In the past two years, researchers have been exploring the precision medicine. Thanks to the development of sequence industry and clinical study, the big data about the precision medicine have been more and more sufficient. However, how to deal with the precision data is still a question for clinicians. We focus on the hot issues that disturb clinicians most, wanting to help them to make suitable decisions between the traditional and precision medicine of breast cancer. We believe the precision medicine is on the way.


Assuntos
Neoplasias da Mama/terapia , Medicina de Precisão , Pesquisa Biomédica , Feminino , Humanos
15.
Phys Rev Lett ; 117(18): 182503, 2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-27835000

RESUMO

Masses of ^{52g,52m}Co were measured for the first time with an accuracy of ∼10 keV, an unprecedented precision reached for short-lived nuclei in the isochronous mass spectrometry. Combining our results with the previous ß-γ measurements of ^{52}Ni, the T=2, J^{π}=0^{+} isobaric analog state (IAS) in ^{52}Co was newly assigned, questioning the conventional identification of IASs from the ß-delayed proton emissions. Using our energy of the IAS in ^{52}Co, the masses of the T=2 multiplet fit well into the isobaric multiplet mass equation. We find that the IAS in ^{52}Co decays predominantly via γ transitions while the proton emission is negligibly small. According to our large-scale shell model calculations, this phenomenon has been interpreted to be due to very low isospin mixing in the IAS.

16.
Phys Rev Lett ; 112(16): 162501, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24815641

RESUMO

In a recent breakup-reaction experiment using a Be12 beam at 29 MeV/nucleon, the 0+ band head of the expected He4+He8 molecular rotation was clearly identified at about 10.3 MeV, from which a large monopole matrix element of 7.0±1.0 fm2 and a large cluster-decay width were determined for the first time. These findings support the picture of strong clustering in Be12, which has been a subject of intense investigations over the past decade. The results were obtained thanks to a specially arranged detection system around zero degrees, which is essential in determining the newly emphasized monopole strengths to signal the cluster formation in a nucleus.

17.
Phys Rev Lett ; 113(26): 262502, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25615314

RESUMO

Excited states in the N=102 isotones 166Gd and 164Sm have been observed following isomeric decay for the first time at RIBF, RIKEN. The half-lives of the isomeric states have been measured to be 950(60) and 600(140) ns for 166Gd and 164Sm, respectively. Based on the decay patterns and potential energy surface calculations, including ß6 deformation, a spin and parity of 6- has been assigned to the isomeric states in both nuclei. Collective observables are discussed in light of the systematics of the region, giving insight into nuclear shape evolution. The decrease in the ground-band energies of 166Gd and 164Sm (N=102) compared to 164Gd and 162Sm (N=100), respectively, presents evidence for the predicted deformed shell closure at N=100.

18.
Phys Rev Lett ; 108(9): 092501, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22463627

RESUMO

Stimulated by recent experimental discoveries, triaxial strongly deformed (TSD) states in (158)Er at ultrahigh spins have been studied by means of the Skyrme-Hartree-Fock model and the tilted-axis-cranking method. Restricting the rotational axis to one of the principal axes--as done in previous cranking calculations--two well-defined TSD minima in the total Routhian surface are found for a given configuration: one with positive and another with negative triaxial deformation γ. By allowing the rotational axis to change direction, the higher-energy minimum is shown to be a saddle point. This resolves the long-standing question of the physical interpretation of the two triaxial minima at a very similar quadrupole shape obtained in the principal-axis-cranking approach. Several TSD configurations have been predicted, including a highly deformed band, which is a candidate for the structure observed in experiment.

19.
Appl Radiat Isot ; 70(7): 1321-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22182628

RESUMO

The quadrupole deformations for the low-lying states in the transitional nuclei 100,101Pd have been deduced through the measurement of their electric quadrupole transition probabilities using the Recoil Distance Doppler Shift Method. The nuclei were studied using a 268 MeV 80Se beam impinging on a thin, self-supporting 24Mg target. States in 100Pd and 101Pd populated by the four and three neutron evaporation channels respectively, with reaction gamma-rays detected using the SPEEDY gamma-ray detection array. The recoiling nuclei were stopped in a copper foil and gamma-ray coincidence data taken at 10 separate target-stopper distances between 35 µm and 750 µm. The mean-lifetimes for the lowest lying 2+ (in 100Pd) and 15/2- (in 101Pd) states were measured to be 13.3(9) ps and 10.8(8) ps respectively. These data are compared with predictions from nuclear Total Routhian Surface calculations, which are found to agree with the experimentally deduced values to within 10%.

20.
Phys Rev Lett ; 105(7): 072501, 2010 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-20868034

RESUMO

The charge exchange spin-dipole (SD) excitations of 208Pb are studied by using a fully self-consistent Skyrme Hartree-Fock plus random phase approximation formalism which includes the tensor interaction. It is found, for the first time, that the tensor correlations have a unique, multipole-dependent effect on the SD excitations; that is, they produce a softening of 1{-} states, but a hardening of 0{-} and 2{-} states. This paves the way to a clear assessment of the strength of the tensor terms. We compare our results with a recent measurement, showing that our choice of tensor terms improves the agreement with experiment. The robustness of our results is supported by the analytic form of the tensor matrix elements.

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