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Additional file 2. Multivariate analysis of the prognosis of the integrated GTV-TNM stratification system in the training cohort and validation cohort.

We investigate theoretically the spin accumulation in a Rashba spin-orbit coupling (SOC) nanoribbon nonadiabatically connected to a normal conductor. Both the nanoribbon and conductor are described by a hard-wall confining potential. Using the scattering matrix approach within the effective free-electron approximation, we have calculated the out-of-plane spin accumulation in the nanoribbon. It is found that the spin accumulation shifts toward the two edges of nanoribbon with the increasing of propagation modes. Specifically, as the Rashba SOC strength increases the spin accumulation in the nanoribbon will be enhanced and this result may suggest us a simple method to control the spin accumulation of the system by Rashba SOC strength.

We investigate theoretically the spin current in a quantum wire with weak Dresselhaus spin-orbit coupling connected to two normal conductors. Both the quantum wire and conductors are described by a hard-wall confining potential. Using the electron wave-functions in the quantum wire and a new definition of spin current, we have calculated the elements of linear spin current density js,xiT and js,yiT (i = x, y, z). We find that the elements jTs,xx and jTs,yy have a antisymmetrical relation and the element jTs,yz has the same amount level as js,xxT and js,yyT. We also find a net linear spin current density, which has peaks at the center of quantum wire. The net linear spin current can induce a linear electric field, which may imply a way of spin current detection.

We theoretically study the electron transport properties for two coupled single-walled carbon nanotube quantum dots connected to metallic electrodes under the irradiation of an external electromagnetic field at low temperatures. Using the standard nonequilibrium Green's function techniques, we examine the time-averaged transmission coefficient and linear conductance. It is shown that by some numerical examples, the photon-assisted inter-dot coupling causes Fano resonance and the conductance of the system is sensitive to the external field parameters. The transport dependence on the external field parameters may be used to detect the high-frequency microwave irradiation.

Protein phosphatase 1 (PP1), a major protein phosphatase important for a variety of cellular responses, is activated in response to ionizing irradiation (IR)-induced DNA damage. Here, we report that IR induces the rapid dissociation of PP1 from its regulatory subunit inhibitor-2 (I-2) and that the process requires ataxia-telangiectasia mutated (ATM), a protein kinase central to DNA damage responses. In response to IR, ATM phosphorylates I-2 on serine 43, leading to the dissociation of the PP1-I-2 complex and the activation of PP1. Furthermore, ATM-mediated I-2 phosphorylation results in the inhibition of the Aurora-B kinase, the down-regulation of histone H3 serine 10 phosphorylation, and the activation of the G(2)/M checkpoint. Collectively, the results of these studies demonstrate a novel pathway that links ATM, PP1, and I-2 in the cellular response to DNA damage.

We theoretically investigate the electrical transport property of a quantum dot with longitudinal optical phonons. The conductance through the dot connected to two leads is calculated by the nonequilibrium Green function within the Landauer-Buttiker framework. The numerical examples of the conductance with different electron-phonon coupling strengths show that the presence of a phonon field typically results in the suppression of the main peak accompanied by some phonon side peaks. Both the main peak and the side peaks are sensitive to the electron-phonon coupling strength, which is related to temperature. Our results for this system are consistent with some related previous works but the calculation is comparatively simple.

We investigate theoretically the ac conductivity of a clean two-channel spinless quantum wire in the presence of both short-ranged intra- and inter-channel electron-electron interactions. In the Luttinger-liquid regime, we formulize the action functional of the system with an external time-varying electric field. The obtained expression of ac conductivity for the system within linear response theory is generally an oscillation function of the interaction strength, the driving frequency as well as the measured position in the wire. The numerical examples demonstrate that the amplitude of ac conductivity is renormalized by the both interactions, and the do conductivity of the system with inter-channel interaction is smaller than that without inter-channel interaction.

We investigate theoretically the electron transport of a two-level quantum dot irradiated under a weak laser held at low temperatures in the rotating wave approximation. Using the method of the Keldysh equation of motion for nonequilibrium Green function, we examine the conductance for the system with photon polarization perpendicular to the tunnelling current direction. It is demonstrated that by analytic analysing and numerical examples, a feature of conductance peak splitting appears, and the dependence of conductance on the incident laser frequency and self-energy are discussed.

We theoretically investigate the spin current for a parabolically confined semiconductor heterojunction quantum wire with weak Rashba spin-orbit coupling by means of the perturbation method. By analytical calculation, it is found that only two components of spin current density is non-zero in the equilibrium case. Numerical examples have demonstrated that the spin current of electron transverse motion is 10(-3) times that of electron longitudinal motion. However, the former one is much more sensitive to the strength of Rashba spin-orbit coupling. These results may suggest an approach to the spin storage device and to the measurement of spin current through its induced electric field.

We theoretically study the low temperature electron transport properties of a weak Rashba spin-orbit coupling (SOC) semiconductor quantum wire connected nonadiabatically to two electrode leads without SOC. The wire and the leads are defined by a parabolic confining potential, and the influence of both the wire-lead connection and the Rashba SOC on the electron transport is treated analytically by means of scattering matrix within effective free-electron approximation. From analytical analysis and numerical examples, we End that the system shows some fractional quantum conductance behaviour, and for some particular wire width a pure spin polarized current exists. Our result may imply a simple method for the design of a spin Elter without involving any magnetic materials or magnetic fields.

We investigate theoretically the electron transport properties of a two-sublevel quantum wire irradiated by a strong laser held resonant with the quasiparticle transition at low temperatures. Using the method of the Keldysh equation of motion for nonequilibrium Green function, we examine the time-averaged conductance for the system with photon polarization parallel and perpendicular to the tunnelling current direction, respectively. We demonstrate that, by analysing some numerical examples, a feature of absolute negative conductance appears in the parallel case, while the conductance shows a symmetry distributed peaks in the perpendicular case.

Using the equation of motion, we investigate theoretically the dynamical ac conductance of a clean Luttinger-liquid quantum wire adiabatically coupled to Fermi liquid electron reservoirs in the presence of short-ranged electron-electron interactions. For a perfect single mode quantum wire, in the limit of zero-ranged interaction we conclude that the static dc conductance of omega -> 0 is e(2)/h, which is independent of the electron interactions. While in the dynamical case of omega not equal 0, the ac conductance oscillates with the amplitude e(2)/h and the period which depends on the interaction strength and the driving frequency as well as the position in the wire.

We theoretically investigate the effect of a single finite-size attractive impurity on the electron transport of a semiconductor quantum wire under the influence of a terahertz electromagnetic field illumination. In the free-particle framework, the time-dependent electronic states are obtained by introducing an unitary transformation, and the electronic transmission of the system is obtained by using the scattering matrix approach. In the case of the field frequency resonant with the lateral energy spacing of the two lowest levels, a step-like structure for the transmission probability versus the total electron energy is predicted. Furthermore, due to the interplay between the single impurity and the applied field, the transmission probability curve in the non-resonant case shows a structure of a resonance dip on the interference pattern background with certain parameters of the impurity.

We study theoretically the low-temperature electronic transport property of a straight quantum wire under the irradiation of a finite-range transversely polarized external terahertz (THz) electromagnetic (EM) field. Using the free-electron model and the scattering matrix approach, we show an unusual behaviour of the electronic transmission of this system. A sharp step-structure appears in the electronic transmission probability as the EM field strength increases to a threshold value when a coherent EM field is applied. We demonstrate that this effect physically comes from the inelastic scattering of electrons with lateral photons through intersubband transitions.

We study the electronic transport of a quantum wire partly irradiated under an external terahertz (THz) electromagnetic field. Using the free-electron model and scattering matrix approach we demonstrate that although the electrons in a ballistic quantum wire only suffer from lateral collision with photons, the reflection of electrons also takes place. More interestingly there is a sharp step-structure in the transmission probability as the total energy of electron increases to a threshold value when the frequency of electromagnetic field is resonant with the separation of lateral levels of the wire. The interference structure of transmission for the system apparently appears when the field only irradiates the middle part of the wire.

We study the nonlinear lattice effect on the ground state in a one-dimensional spinless Holstein model with nonadiabitical coupling and squeezing by means of the parameter variational approach. Our results show that the introduction of a hard quartic term in the lattice potential increases the ground state energy of the system when electron-phonon coupling is strong, and the increment is sensitive to the magnitude of the lattice quartic force constant. In this case the nonlinear lattice effects should be taken into account to describe satisfactorily some physical properties of the coupling system.

A direct approach has been developed for soliton perturbations based on the Green's function. We first linearized the soliton equation and then derived the Green's function corresponding to approximation equations of different orders. Finally, we obtained the effects of perturbation on a soliton, namely both the slow time dependence of the soliton parameters and the corrections up to the second-order approximation. The higher-order effects can also be obtained in the same way.

We analytically study the nonlinear localized gap modes in a one-dimensional atomic chain with uniform atomic mass but two periodically alternating force constants between the nearest neighbors by means of a quasi-continuum approximation. This model simulates a row of atoms in the direction of a diamond-structure type of crystals or molecular crystals with alternating double and single bonds. For this lattice system, we find that the harmonic plus quartic anharmonic terms of inter-site potential produce a new type of nonlinear localized gap modes with a slightly asymmetry distribution of atomic displacements. These localized gap modes are somewhat different from widely studied localized gap modes with a symmetry atomic displacement distribution in diatomic ion lattices.

The soliton perturbations of the modified Korteweg de Vries equation corresponding to different signs of the nonlinear term are studied. The first-order effects of perturbation on a soliton, namely, both the slow time-dependence of the soliton parameters and first-order corrections are derived in a direct approach based on the separation of variables.

A direct approach is used to investigate perturbations about a kink solution for nonlinear Klein–Gordon models. Effects of perturbations on a kink are derived in this scheme. After linearizing the initial equations by making use of derivative expansion method from classical perturbation theory, the solution for the first-order correction is derived by means of the method of Laplace transformation. The parameter variations are naturally given by the secular conditions.

We address velocity-modulation control of electron wave propagation in a normal/ferromagnetic/normal silicene junction with local variation of Fermi velocity, where the properties of charge, valley, and spin transport through the junction are investigated. By matching the wavefunctions at the normal-ferromagnetic interfaces, it is demonstrated that the variation of Fermi velocity in a small range can largely enhance the total conductance while keeping the current nearly fully valley- and spin-polarized. Further, the variation of Fermi velocity in ferromagnetic silicene has significant influence on the valley and spin polarization, especially in the low-energy regime. It may drastically reduce the high polarizations, which can be realized by adjusting the local application of a gate voltage and exchange field on the junction.

We numerically study the intrinsic localized vibrational modes in a diatomic chain with different masses and alternating force constants between nearest neighbors. This model simulates a row of atoms in the [111] direction of sphalerite-structure crystal. We found that the harmonic and quartic anharmonic terms in the nearest-neighbor interaction potential produce the intrinsic localized modes with frequencies above the optical branch or in the gap of the linear spectrum, the distribution patterns of atom amplitudes are asymmetry with a form of quasi-even or quasi-odd-parity, and the inclusion of cubic term in the potential lowers the frequencies of the modes and introduces static displacements for the atoms.

The soliton perturbations for the combined Korteweg de Vries and modified Korteweg de Vries (KdV-MKdV) equation are studied. The first-order effects of perturbation on a soliton, namely both the slow time-dependence of the soliton parameters and the first-order correction are derived through constructing the appropriate Green's function.

Irradiation often causes cell cycle arrest in tumor cells. This study was to observe the abrogation of radiation-induced G(2) phase arrest of p53 mutated human cancer cell lines by 7-hydroxystaurosporine (UCN-01), and explore the mechanism.Human nasopharyngeal carcinoma cell line CNE-1 and human lung adenocarcinoma cell line 973, both with p53 mutation, were used in this study. Human fibroblastoma cell line HT-1080 was used as control. Flow cytometry was used to observe the effects of irradiation on cell cycle of these 3 cell lines, and abrogation effect of UCN-01 on radiation-induced G(2) phase arrest. Western blot was used to detect phosphorylated CDC2-Tyr15 during the abrogation process.Irradiation resulted in G(2) phase arrest in CNE-1 cells and 973 cells. Proportion of cells in G(2) phase increased from 18.4% to 43.6% in CNE-1 cell line, and from 14.8% to 42.8% in 973 cell line after 2 Gy of irradiation. G(1) phase arrests, measured by "S phase cells consumption", of CNE-1 cells and 973 cells were much lower than that of HT-1080 cells (14.8% and -1.2% vs. 57.0%). Radiation-induced G(2) phase arrests were abrogated by UCN-01 from 63.5% to 16.1% in CNE-1 cell line, and from 35.4% to 16.3% in 973 cell line. UCN-01 suppressed the expression of radiation-induced phosphorylation of CDC2-Tyr15, which was in accordance with the abrogation of radiation-induced G(2) phase delay.Main effect of irradiation on cell cycle of p53 mutated CNE-1 cells and 973 cells is G(2) phase arrest. UCN-01 is able to abrogate radiation-induced G(2) phase, which is associated with the reduction of phosphorylated CDC2-Tyr15.