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Neoadjuvant therapy is recommended for locally advanced esophageal cancer, but the optimal strategy remains unclear. We aimed to evaluate the safety and efficacy of neoadjuvant chemoradiotherapy (nCRT) vs neoadjuvant chemotherapy (nCT) followed by minimally invasive esophagectomy (MIE) for locally advanced esophageal squamous cell carcinoma (ESCC).Eligible patients staged as cT3-4aN0-1M0 ESCC were randomly assigned (1:1) to the nCRT or nCT group stratified by age, cN stage and centers. The chemotherapy, based on paclitaxel and cisplatin, was administered to both groups, while concurrent radiotherapy added for nCRT group; then MIE was performed. The primary endpoint was 3-year overall survival. This study is registered with ClinicalTrials.gov, NCT03001596.A total of 264 patients were eligible for the intention-to-treat analysis. By November 30, 2021, 121 deaths had occurred. The median follow-up was 43.9 months (interquartile range, 36.6-49.3 months). The overall survival in the intention-to-treat population were comparable between nCRT and nCT strategy (hazard ratio [HR], 0.82; 95% CI, 0.58-1.18; P = 0.28), with a 3-year survival rate of 64.1% (95% CI, 56.4% to 72.9%) vs. 54.9% (95% CI, 47.0% to 64.2%), respectively. There were also no differences in progression-free survival (HR, 0.83; 95% CI, 0.59-1.16; P = 0.27) and recurrence-free survival (HR, 1.07; 95% CI, 0.71-1.60; P = 0.75), although the pathological complete response (pCR) in the nCRT group (27.7%, 31/112) was significantly higher than that in the nCT group (2.9%, 3/104) (P0.001). Besides, a trend of lower risk of recurrence was observed in the nCRT group (P = 0.063), while the recurrence pattern was similar (P = 0.802).NCRT followed by MIE was not associated with significantly better overall survival than nCT among patients with cT3-4aN0-1M0 ESCC. The results underscore the pending issue of the best strategy of neoadjuvant therapy for locally advanced bulky ESCC.

The β-delayed γ-ray spectroscopy of neutron-rich 123;125Ag isotopes is investigated at the Radioactive Isotope Beam Factory of RIKEN and the long-predicted 1/2¯ β-emitting isomers in 123;125Ag are identified for the first time. With the new experimental results, the systematic trend of energy spacing between the lowest 9/2+ and 1/2¯ levels is extended in Ag isotopes up to N = 78, providing a clear signal for the reduction of the Z = 40 subshell gap in Ag towards N = 82. Shellmodel calculations with the state-of-the-art VMU plus M3Y spin-orbit interaction give a satisfactory description of the low-lying states in 123;125Ag. The tensor force is found to play a crucial role in the evolution of the size of the Z = 40 subshell gap. The observed inversion of the single particle levels around 123Ag can be well interpreted in terms of the monopole shift of the π1g9/2 orbitals mainly caused by the increasing occupation of ʋ1h11/2 orbitals.

The first heavy ion fusion–evaporation reaction study for 74Ge has been performed through the reaction channel Zn70(Li7,2np)Ge74 at beam energies of 30 and 35 MeV. Previously known yrast band is extended to higher spins and five new collective bands are established. Based on comparison with the neighboring 72,76Ge isotopes, an intermediate pattern of energy staggering S(I) is observed in the γ band of 74Ge. The collective structure of 74Ge, including the excitation energies and transition probabilities of ground-state band and γ band, is reproduced by the state-of-the-art five-dimensional collective Hamiltonian (5DCH) model constructed from the covariant density functional. By including the 72,76,78Ge isotopes, systematical investigation of the structure evolution in Ge isotopes is performed. Based on the systematic comparisons and analysis, the triaxial evolution with spin in 74Ge is revealed and 74Ge is found to be the crucial nucleus marking the triaxial evolution from soft to rigid in Ge isotopes.

A knockout reaction induced by 6He at 61.2 MeV/u was carried out at the HIRFL-RIBLL radioactive beam line. The α core fragments at forward angles were detected in coincidence with the recoiled protons at large angles. From this coincident measurement the valence nucleon knockout mechanism and the core knockout mechanism can be separated according to the polar angle correlation between the core fragments and the recoiled protons. It is demonstrated that, when reconstructing the resonant state of a weakly bound nucleus, the contamination resulting from the core knockout mechanism should be eliminated in order to obtain the correct structure information.

The timing performance of a two-dimensional position-sensitive silicon detector (PSD) was tested using 6He beam. An approximately linear relationship between the position of incident particles and the timing output of the detector is found. A qualitative explanation is given to why a relatively long charge collection time on the resistive anode leads to the large time diffusion of the timing output. It is estimated that the maximum timing shift between the edge area and the central area may attain an order of ∼ 1 μ s .

Neutron detection efficiency for a long wedge-shaped plastic scintillation detector was measured by using the Am/Be neutron source. The overall efficiency attains 23% at around 2 MeV and decreases to 15% at about 5 MeV. The experimental results are in agreement with the Monte Carlo simulation calculations.

Low Pressure Multi-Wire Proportional Chambers (LPMWPC) were made in the laboratory and the systematic tests were carried out. The position resolution of the chamber is about 0.5 mm and the time resolution is about 1.5 ns. The detection efficiency is higher than 90% for light nuclei at low and intermediate energies, and for beam intensities lower than 105 pps. This kind of detector is applicable for monitoring the radioactive ion beam which is in general characterized by low intensity and large spot. Application of new read-out techniques may allow to improve the beam intensity capability.

To reduce the steam loss and raise the efficiency of the steam turbine, the vapour seals are applied in the inner cylinder of the steam turbine. The small gap may easily results in the rubbing happening in the inner cylinder. Sometimes, the rotor is a flexible rotor. In this paper, dynamic response of rubbing happening in a flexible rotor-bearing system was studied. A simplified flexible rotor-bearing system was constructed, whose rotating speed was between the 1st and 2nd critical rotating speed. Thermal effect was considered in the analysis, i.e. the rubbing introduce heat and result in the thermally induced vibration. The transient thermal bow was treated as a pair of moments functioning on the shaft segment where rubbing happened. Simulation shows the amplitude and phase of vibration would be stable after a long time. The severity of rubbing affect the stabilization time, which could be regarded as a diagnostic feature to identify the severity of rub happening in a flexible rotor-bearing system. Keywords-thermally induced vibration; equivalent thermal moment; stabilization time; rubbing; flexible rotor-bearing system

Measurements of α -fragment coincidences in the reaction plane in the reaction 84 Kr+ 27 Al at 8.5 MeV/u show that the fully energy-damped symmetric fragments are dominantly produced in deeply inelastic collisions. From the measured α and proton multiplicities, the reaction time is deduced to be 8×10 −21 seconds. The diffusion model calculations incorporating this reaction time reproduce well the measured fragment charge distributions.

Fission fragments, heavy reaction residues and the multiplicity of all simultaneously evaporated neutrons are observed from the reactions 40 Ar + Au, Th over a wide range of incident 40 Ar energy from 27 to 77 MeV/u. The inclusive neutron-multiplicity distributions prove the invariance of energy dissipation with incident energy in these reactions: peripheral collisions with low dissipation and central collisions with high dissipation contribute invariably about half of the reaction cross section. Two fragment correlations and fragment angular distributions show that fission is, for energies in excess of 35 MeV/u, progressively escorted by the emission of lighter complex particles, while the importance of fission generally fades away in favour of very heavy-residue production and, to a smaller extent yet in the considered energy range, eventually also in favour of true multifragmentation.

Differential cross sections for the elastic scattering of halo nucleus 6He on proton target were measured at 82.3 MeV/u. The experimental results are well reproduced by optical model calculations using global potential KD02 with a reduction of the depth of real volume part by a factor of 0.7. A systematic analysis shows that this behavior might be related to the weakly bound property of unstable nuclei.

Projectile-like fragments have been measured in 40 Ar induced reactions on 197 Au at 27, 35 and 44 MeV/u and on 103 Rh at 27 MeV/u. The excitation energies deposited in the associated target-like fragments have been estimated from multiplicities of coincident neutrons measured with a 4π detector. The angular and energy distributions of the projectile-like fragments can be understood in terms of a damped process. The energy dissipation can be understood by assuming a non-equilibrium emission or abrasion of nucleons from the system. For the lightest detected fragments, the occurrence of yet other mechanisms cannot be excluded.

The differential cross sections for reactions 8He(p, d)7Heg.s and 8He(p, t)6He2+ were measured by the coincidence of d + 6 He and t + 4He in a wide angular range from 15 to 130 degree in the center-of-mass system. The cross sections of the 8He(p, t)6Heg.s reaction were extremely lower than that of 8He(p, t)6He2+ reaction, and was not obtained from the present data. The experimental results were compared to the preliminary theoretical calculations in the frame of adiabatic distorted-wave approximation with the code Fresco. The results show that the configuration of (1p3/2)2(1p1/2)2 may have some probability in the ground state wave function of 8He. The cluster structure of 8He = 5H + 3H could not be neglected.

Breakup reactions of the double borromean nucleus 8He were measured at 82.3 MeV/u on CH2 and C targets. The coincident detection of two decaying neutrons and the high performance for neutron cross talk rejection are realized in this experiment. The relative energy spectrum for 8He was reconstructed with good statistics. The spectrum exhibits a structure of two resonant peaks, one at an excitation energy of about 3.0 and the other at about 4.14 MeV, respectively. Substantially larger cross section for the first resonance is observed in comparison to the results reported previously.

Inclusive neutron multiplicity distributions were measured by means of 4π liquid-scintillator detectors for Ar and Kr-induced reactions at 44 MeV/nucleon and 32 MeV/nucleon, respectively. For all the systems studied, the observed distributions exhibit a bump structure at large multiplicity, corresponding to highly dissipative collisions. For Ar-induced reactions, the excitation energies necessary to explain the most probable neutron multiplicity associated with these dissipative collisions are estimated, the correspondence between excitation energy and neutron multiplicity being calculated in the framework of the statistical model. The so-obtained values of excitation energies, which are systematically lower than those predicted using the massive-transfer picture, are discussed.

Complex-fragment emission from the 44 and 77 A · MeV 40 Ar + 197 Au reaction has been investigated. Equilibrium and non-equilibrium components have been identified which are discussed in terms of statistical emission from the hot target-like fragment and of a possible persistence of a deep-inelastic process.

Multiplicities of neutrons and light charged particles associated with central collisions have been measured in the energy range 27–77 MeV/u for the systems 40Ar+197Au, 232Th. The experiments demonstrate the occurrence of a saturation of the thermal energy deposited in the system around 650 MeV, corresponding to a constant internal temperature close to 5 MeV.

A 4π detector has been used to measure the neutron multiplicity associated with peripheral heavy ion reactions induced at 27.2 MeV/u. A strong correlation is observed between the number of emerging neutrons and the mass of the projectile-like-fragment. However, the large energy dissipation which is observed is still too small to support the idea of a pure massive transfer process.