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Efficient particles acceleration technology is of unique significance to the exploration of elementary particles, defeating cancer, and developing new materials. With the injection of the relativistic electron beam into the micro-tube, the strong transverse self-consistent field acts on the inner-wall of the plasma or the metal tube and causes the surface-nanometer electron film to oscillate in and out of the surface. Due to the mid-infrared radiation from the oscillating electrons continuously, a stable and periodic intense field of about tens of GV/m, propagates synchronously with the electron beam and accelerates the positron bunch in a stable phase. Several micrometers of the transverse spatial misalignment of the positron injection is tolerant due to the uniformity of the intense field. The acceleration scheme can realize cascade acceleration of a single positron bunch and series acceleration of multiple positron bunches easily, making it possible to accelerate positron bunch continuously, stably and efficiently., Comment: 22 pages, 7 figures

The dark photon is a new gauge boson which arises from an extra $$U'(1)$$ U ′ ( 1 ) gauge symmetry. In this paper, a novel dark photon production mechanism based on MeV-scale $$\gamma $$ γ – $$\gamma $$ γ collider is considered: $$\gamma \gamma \rightarrow \gamma A'$$ γ γ → γ A ′ . With the aid of PACKAGE-X, differential cross section of $$\gamma \gamma \rightarrow \gamma A'$$ γ γ → γ A ′ is obtained, as a function of the kinetic mixing parameter $$\varepsilon $$ ε and dark photon mass $$m_{A'}$$ m A ′ . Taking the light-by-light scattering as background, the constraints on the dark photon parameter space for different time intervals in a MeV-scale $$\gamma $$ γ – $$\gamma $$ γ collider are also given.

Additional file 2: Supplement Table 2. Results of differential expression analysis of RBPs in the TCGA database ccRCC.

Additional file 4: Supplementary Figure 1. Survival analysis of 17 survival-related RBPs in ccRCC.

Additional file 5. RNA extraction from tissues.

We explore the axionic dark matter search sensitivity with a narrow-band detection scheme aiming at the axion-photon conversion by the static electric field inside a cylindrical capacitor. An alternating magnetic field signal is induced by effective currents as the axion dark matter flows perpendicularly through the electric field. At low axion masses, like in a KKLT scenario, front-end narrow band filtering is provided by using LC resonance with a high $Q$ factor, which enhances the detectability of the tiny magnetic field signal and also leads to a thermal noise as the major background that can be reduced at cryogenic conditions. We demonstrate that high $g_{a\gamma}$ sensitivity can be achieved by using a strong electric field. The QCD axion theoretical parameter space can be reached with high $E\sim$ GVm$^{-1}$ field strength. Using the static electric field scheme essentially avoids exposing the sensitive superconducting pickup to an applied laboratory magnetic field., Comment: 6 pages, 2 figures, 1 table

Additional file 3: Supplement Table 3: Number of nodes in the PPI network.

Additional file 1: Supplement Table 1. The 1542 RBPs genes in human cells.

Recently, high electrical conductors have been detected beneath some fore-arcs and are believed to store voluminous slab-derived fluids. This implies that the for-arc mantle wedge is permeable for aqueous fluids. Here, we precisely determine the dihedral (wetting) angle in an olivine–NaCl–H2O system at fore-arc mantle conditions to assess the effect of salinity of subduction-zone fluids on the fluid connectivity. We find that NaCl significantly decreases the dihedral angle to below 60° in all investigated conditions at concentrations above 5 wt% and, importantly, even at 1 wt% at 2 GPa. Our results show that slab-released fluid forms an interconnected network at relatively shallow depths of ~80 km and can partly reach the fore-arc crust without causing wet-melting and serpentinization of the mantle. Fluid transport through this permeable window of mantle wedge accounts for the location of the high electrical conductivity anomalies detected in fore-arc regions., The authors here perform experiments to investigate the dihedral angle of olivine-H2O and olivine-H2O-NaCl systems. The observed effect of NaCl to decrease dihedral angles allows fluids to percolate through forearc mantle wedge and to accumulate in the overlying crust, accounting for the high electrical conductivity anomalies in forearc regions.

[Objectives] In order to numerically predict the self-propulsion factors of high speed underwater vehicles equipped with Contra-Rotating Propellers (CRP),[Methods] RANS modeling approaches are developed for vehicle resistance,self-propulsion and CRP open-water simulation. In terms of resistance and open-water performance,the modeling accuracy are validated by comparisons with model experiments. Based on quasi-steady and unsteady simulations of a high speed underwater vehicle at full scale,the self-propulsion factors are analyzed and compared.[Results] The comparison of the numerical and experimental results at the model scale indicates that the simulation error margin of vehicle resistance is less than 3%,while those of CRP thrust and torque are less than 2% and 4% respectively. The numerically simulated full-scale resistance is 3% lower than that predicted by the model test data. The self-propulsion factors yielded from full-scale RANS simulations are all reasonable in magnitude. The self-propulsion factors yielded from the quasi-steady and unsteady models differ by less than 2%, indicating that the quasi-steady model is an economical choice for engineering applications.[Conclusions] The present modeling approaches are capable of supplying self-propulsion factors for CRP design with reasonable accuracy,and are expected to enhance design accuracy and work efficiency.

The dark photon is a new gauge boson which arises from an extra U'(1) gauge symmetry. In this paper, a novel dark photon production mechanism based on MeV-scale $��$-$��$ collider is considered: $����\rightarrow ��A'$. With the aid of PACKAGE-X, differential cross section of $����\rightarrow ��A'$ is obtained, as a function of the kinetic mixing parameter $\varepsilon$ and dark photon mass $m_{A'}$. Taking the light-by-light scattering as background, the constraints on the dark photon parameter space for different time intervals in a MeV-scale $��$-$��$ collider are also given.

Pertechnetate (TcO4-) is a component of low-activity waste (LAW) fractions of legacy nuclear waste, and the adsorption removal of TcO4- from LAW effluents would greatly benefit the site remediation process. However, available adsorbent materials lack the desired combination of low cost, radiolytic stability, and high selectivity. In this study, a ZnO nanoparticle-anchored biochar composite (ZBC) was fabricated and applied to potentially separate TcO4- from radioactive effluents. The as-synthesized material exhibited γ radiation resistance and superhydrophobicity, with a strong sorption capacity of 25,916 mg/kg for perrhenate (ReO4-), which was used in this study as a surrogate for radioactive pertechnetate (TcO4-). Additionally, the selectivity for ReO4- exceeded that for the competing ions I-, NO2-, NO3-, SO42-, PO43-, Cu2+, Fe3+, Al3+, and UO22+. These unique features show that ZBC is capable of selectively removing ReO4- from Hanford LAW melter off-gas scrubber simulant effluent. This selectivity stems from the synergistic effects of both the superhydrophobic surface of the sorbent and the inherent nature of sorbates. Furthermore, density functional theory (DFT) calculations indicated that ReO4- can form stable complexes on both the (100) and (002) planes of ZnO, of which, the (002) complexes have greater stability. Electron transfer from ReO4- on (002) was greater than that on (100). These phenomena may be because (002) has a lower surface energy than (100). Partial density of state (PDOS) analysis further confirms that ReO4- is chemisorbed on ZBC, which agrees with the findings of the Elovich kinetic model. This work provides a feasible pathway for scale-up to produce high-efficiency and cost-effective biosorbents for the removal of radionuclides.

The nature of matter creation is one of the most basic processes in the universe. According to the quantum electrodynamics theory, matters can be created from pure light through the Breit Wheeler (BW) process. The multi-photon BW process has been demonstrated in 1997 at the SLAC, yet the two-photon BW process has never been observed in the laboratory. Interest has been aroused to investigate this process with lasers due to the developments of the laser technology and the laser based electron accelerators. The laser based proposals may be achieved with NIF and ELI, provided that the signal-to-noise (S/N) ratio of BW is high enough for observation. Here, we present a clean channel to observe the matter creation via a gamma-gamma collider by using the collimated {\gamma}-ray pulses generated in the interaction between 10-PW lasers and narrow tubes. More than $3.2\times 10^8$ positrons with a divergence angle of $\sim 7$ degrees can be created in a single pulse, and the S/N is higher than 2000. This scheme, which provides the first realization of gamma-gamma collider in the laboratory, would pave the developments of quantum electrodynamics, high-energy physics and laboratory astrophysics.

The laser-ion acceleration from the ultra-short and ultra-intense laser-matter interactions attracts more and more interest nowadays. When a laser pulse interacts with a target, relativistic electrons are generated in a period of few femtoseconds and driven away by the ponderomotive force, then a huge charge-separation field forms. In general cases, the ion acceleration is determined by this charge-separation field and the scale length of the plasma density. A general time-dependent solution is obtained to describe laser-plasma isothermal expansions into a vacuum, which is the fundamental theory of the laser-ion acceleration. It is adequate for non-quasi-neutral plasmas and different types of the scale length of the density gradient. The previous solutions are some special cases of our general solution. It is found that there exist both a compression layer of the ion velocity distribution and a potential well for some initial conditions. However, many unaccounted idiographic solutions, which may be used to reveal new mechanisms of ion acceleration, may be deduced from our general solutions.

Calibration of solid state nuclear track detector CR-39 was carried out with very low-energy monoenergetic protons of 20–100 keV from a Cockcroft Walton accelerator. To reduce the beam of the proton from the accelerator, a novel method was adopted by means of a high voltage pulse generator. The irradiation time of the proton beam on each CR-39 sheet was shortened to one pulse with duration of 100 ns, so that very separated proton tracks around 10 4 cm - 2 can be irradiated and observed and measured on the surface of the CR-39 detector after etching. The variations of track diameter with etching time as well as with proton energy response curve has been carefully calibrated for the first time in this very low energy region. The calibration shows that the optical limit for the observation of etched tracks of protons in CR-39 is about or a little lower that 20 keV, above which the proton tracks can be seen clearly and the response curve can be used to distinguish protons from the other ions and determine the energy of the protons. The extension of response curve of protons from traditionally 20 to 100 keV in CR-39 is significant in retrieving information of protons produced in the studies of nuclear physics, plasma physics, ultrahigh intensity laser physics and laser acceleration.

We investigate the kinetic energy of expanding plasma of a solid target heated by a ultra-short and ultra-intense laser pulse and the efficiency of energy coupling between the ultra-intense laser pulse and the solid target, in order to increase the utilization ratio of laser energy and to raise the neutron generation farther. Some new ideas about improving the energy utilization by head-on collisions between the expanding plasmas are proposed. The significance is the raise of generation of shorter duration neutron, of the order of picoseconds, which allows for an increase of energy resolution in time-of-flight experiments and also for the investigation of the dynamics of nuclear processes with high temporal resolution.

Proton acceleration experiments were performed by using an ultra-short laser to irradiate gold foils of 5 m and 2.1 m in thickness. The ultra-short laser pulse had the pulse duration of 120 fs and energy of 11 mJ. The peak focal intensity remained around 61016 W/cm2. A Thomson ion spectrometer with CR39 plastic nuclear track detectors were used to observe spectra of the accelerated protons. The spectrum of the 2.1 m foil featured a single peak around 74 keV due to the inefficiency of protons. The maximum energies and efficiencies of accelerated protons increased with decreasing the target thickness. The results were explained by the energy loss of electron transmission and a geometrical effect on hot electron recirculation.

With the increasing scale of the Peer-to-Peer (P2P) network, the contradictions among the scope expanding, the expenditure of time is reducing and the network loading of content search is growing more serious. In this chapter, an evolving model of P2P content distribution network (CDN) based on the prediction of user requirements is proposed in which the organization of the P2P CDN is evolved continuously according to the improvement of the prediction of user requirements. In the model, the peers and the surrogates that have the requiring contents of a designate peer will be assembled at nearby locations to the designated peer, and then more replicas can be found in smaller search scope and shorter time expending. Simulative experiments indicate the evolving model can acquire much smaller mean response time and mean distribution time.

A new laser-proton acceleration structure combined by two relativistic electron shells, a suprathermal electron shell and a thermal electron cloud is proposed for $a\gtrapprox80\sigma_0$, where a is the normalized laser field and $\sigma_0$ is the normalized plasma surface density. In the new region, a uniform energy distribution of several GeV and a monoenergetic hundreds-of-MeV proton beam have been obtained for $a=39.5$. The first relativistic electron shell maintains opaque for incident laser pulse in the whole process. A monoenergetic electron beam has been generated with energy hundreds of MeV and charge of hundreds of pC. It is proposed a stirring solution for relativistic laser-particle acceleration., Comment: 9 pages, 5 figures

Collaborative filtering is a widely-used recommendation algorithm. Neighbor selection is an important step in collaborative filtering recommendation. Selected neighbors will have direct influence to the recommendation. In traditional collaborative filtering algorithm, similarity is the only factor to determine which users should be selected as neighbors. However, the count of common rated items can indicate the effect of the similarity of both users. In this paper, an improved approach to collaborative filtering algorithm is proposed in which the count of common rated items is taken as an important factor in neighbor selection. Experimental results demonstrate the approach can achieve better recommendation quality.

Siemens Automotive (VDO) algorithm is widely used in the evaluation of knock. But VDO algorithm can't evaluate the intensity accurately when the knock occurs earlier than the peak pressure. An algorithm based on VDO algorithm to evaluate the knock has been developed, and is called Moving Windows algorithm. Moving Windows algorithm uses two moving windows of the same width to analyze the high frequency pressure oscillation in a specified crank angle period. The high frequency pressure oscillations' energy in one window can be evaluated by the integral of the modulus of the high frequency pressure oscillations. The knock indicators ΔK max and K I of the Moving Windows algorithm were determined by comparing the two moving windows' energy. The Moving Windows algorithm can detect the start point of the knock, and its knock intensity indicators have better accuracy than that of the VDO algorithm.

Although a variety of recommendation techniques have been proposed in recent years, collaborative filtering (CF) has been considered to be the most successful recommendation technique. Data sparsity is one of the problems which attract most attention from researchers. Data sparsity means there are lots of users having no or a small amount of rated item. Prediction to rating score of user's unrated items is imprecision. In contrast to the data sparsity problem, what is called as loyal-user problem in this paper is neglected. In this paper, the loyal-user problem is analyzed and an approach is proposed to solve the problem. The experimental results also demonstrate the effectiveness of the method.

A two-dimension self-similar solution is proposed for a plasma expansion with anisotropic pressure. With the solution, it depends on the relationship between the ratio of the longitudinal and the transverse temperature of the plasma, $\kappa^2$ and the electron-ion mass ratio, $\mu$, that the plasma front is composed by a part of hyperbolic (or a plane) and a small pointed projection at the center or a part of an ellipse. Zhang and coworkers's experiments (PRL, 99, 167602 (2007))support our results for $\kappa^2\in(\tau,1]$. For $\kappa^2\leq\tau$, there is an anomalous high-energy plasma emission at the angle of near $90^{\text{o}}$ due to longitudinal Coulomb explosion., Comment: 10 pages, 4 figures, submitted to Physical Review Letters

Contrary to the superposition principle, it is well known that photorefraction exists in the vacuum with the presence of a strong static field, a laser field, or a rotational magnetic field. Different from the classical optical crystals, the refractive index also depends on the phase of the strong electromagnetic field. We obtain the phase and direction dependence of the refractive index of a probe wave incident in the strong field of a circular-polarized plane wave by solving the Maxwell equations corrected by the effective Lagrangian. It may provide a valuable theoretical basis to calculate the polarization evolution of waves in the strong electromagnetic circumstances of pulsar or neutron stars.

Ultrashort 1022–1024 W/cm2 laser pulses will offer the possibility of producing monoenergetic electron beams in the GeV—TeV level in the future. A laser-electron acceleration scheme is proposed by the interaction between a thin solid foil and an ultra-intense laser pulse for α0 ≥ 800σ0, where α0 is the normalized laser field and σ0 is the normalized plasma surface density. The energy of the electrons as a function of time can be described by a simple model which indicates that an exponential relationship exists between the energy and the normalized time τ. A quasi-monoenergetic high density electron beam with 1.3 GeV energy and a 2.2% energy spread has been predicted for α0 = 223.5 by particle-in-cell simulations. Characteristics of the ultra-high density electron layer formed in the early period of the acceleration are discussed.

A new laser-proton acceleration scheme consisting of two relativistic electron layers, a suprathermal electron layer and a thermal electron cloud is proposed for a0 80σ0, where a0 is the normalized laser field and σ0 is the normalized plasma surface density. This is essentially different from target normal sheath acceleration and radiation pressure acceleration. The persistent opaqueness of the first relativistic electron layer for the incident circular-polarization laser pulse and electron recirculation are key points in forming the new acceleration scheme. A proton beam with a uniform energy distribution in the energy range 1–2 GeV and a monoenergetic proton beam with hundreds of MeV have been predicted for a0 = 39.5.

Forward fast protons are generated by the moderate-intensity laser–foil interaction. Protons with maximum energy 190 keV are measured by using magnetic spectrometer and CR-39 solid state track detectors along the direction normal to the rear surface. The experimental results are also modeled by the particle-in-cell method, investigating the time-varying electron temperature and the rear sheath field. The temporal and spatial structure of the sheath electrical field, revealed in the simulation, suggests that these protons are accelerated by target normal sheath acceleration (TNSA) mechanism.

要約のみ, 課程

The Circular Electron Positron Collider (CEPC) is a large international scientific facility proposed by the Chinese particle physics community to explore the Higgs boson and provide critical tests of the underlying fundamental physics principles of the Standard Model that might reveal new physics. The CEPC, to be hosted in China in a circular underground tunnel of approximately 100 km in circumference, is designed to operate as a Higgs factory producing electron-positron collisions with a center-of-mass energy of 240 GeV. The collider will also operate at around 91.2 GeV, as a Z factory, and at the WW production threshold (around 160 GeV). The CEPC will produce close to one trillion Z bosons, 100 million W bosons and over one million Higgs bosons. The vast amount of bottom quarks, charm quarks and tau-leptons produced in the decays of the Z bosons also makes the CEPC an effective B-factory and tau-charm factory. The CEPC will have two interaction points where two large detectors will be located. This document is the second volume of the CEPC Conceptual Design Report (CDR). It presents the physics case for the CEPC, describes conceptual designs of possible detectors and their technological options, highlights the expected detector and physics performance, and discusses future plans for detector R&D and physics investigations. The final CEPC detectors will be proposed and built by international collaborations but they are likely to be composed of the detector technologies included in the conceptual designs described in this document. A separate volume, Volume I, recently released, describes the design of the CEPC accelerator complex, its associated civil engineering, and strategic alternative scenarios., 424 pages