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We present a joint experimental-theoretical study on the effect of the carrier-envelope phase (CEP) of a few-cycle pulse on the atomic excitation process. We focus on the excitation rates of argon as a function of CEP in the intensity range from 50-300 TW/cm$^2$, which covers the transition between the multiphoton and tunneling regimes. Through numerical simulations based on solving the time-dependent Schr\"{o}dinger equation (TDSE), we show that the resulting bound-state population is highly sensitive to both the intensity and the CEP. Because the intensity varies over the interaction region, the CEP effect is considerably reduced in the experiment. Nevertheless, the data clearly agree with the theoretical prediction, and the results encourage the use of precisely tailored laser fields to coherently control the strong-field excitation process. We find a markedly different behavior for the CEP-dependent bound-state population at low and high intensities with a clear boundary, which we attribute to the transition from the multiphoton to the tunneling regime., Comment: 6 pages, 4 figures

The aim of this study was to investigate the mechanism of hepatocyte apoptosis and regeneration after partial hepatectomy in obstructive jaundice (OJ) rats under different drainage methods of bile acid intervention. Forty male Sprague Dawley rats were randomly divided into five groups. An OJ rat model was established by the following protocols. Seven days after obstruction, an SD rats model with 70% partial hepatectomy was established by different drainage methods of OJ. Blood and liver tissue samples were collected from rats 72 h after surgery; 72 h after partial hepatectomy (PH), the liver regeneration rate, the expression of proliferating cell nuclear antigen (PCNA) and the level of mitotic index (MI) in the internal biliary drainage (IBD) group were higher than those in external biliary drainage (EBD) group (P less than 0.05). Those in the EBD group were higher compared to the OJ group (P less than 0.05). There was no significant difference among the IBD group, EBD+CA group and (SO) sham operation group (P0.05). Bax expressions had the same trend as AI in the five groups. The expression of Bcl-2 was increased in the IBD group and EBD+CA group, which was statistically higher compared to the SO group (P less than 0.05). In conclusion, both internal and external drainage can relieve biliary obstruction. The difference in liver regeneration caused by external drainage and internal drainage may be attributed to the destruction of bile acid enterohepatic circulation, which increases hepatocyte apoptosis and affects liver regeneration.

This study is focused on the preparation and characterization of microencapsulated paraffin with Poly (methyl methacrylate-co-acrylic acid) as a shell for thermal energy storage. Microencapsulation of paraffin has been carried out by emulsion polymerization. Test results show that the paraffin in the microcapsules melts at 60°C and it has a latent heat of 113 J/g at melting. Accelerated thermal cycling tests also indicate that the material had good thermal reliability. The average diameter was found to be 32 μm under the stirring speed of 400 rpm. It endows the phase change material certain leakage resistance, solvent resistance, and acid and alkali resistance to improve the compatibility to the environment.

We present percent-level accurate ionisation yields of atomic hydrogen, argon, krypton, and xenon by few-cycle lasers. From these measurements, a peak laser intensity calibration standard is derived, accurate to 1.3% in the 1014 W/cm2 regime.

We present a theoretical study of the energy loss of highly charged ions undergoing distant collisions at grazing incidence angles with the surface of microcapillary targets. The interaction of highly charged ions with the internal surface of the microcapillary is treated within the framework of linear response theory. The specular reflection model and the time-dependent density functional approach are used to calculate the linear response functions. As projectiles we consider 2.1 keV/amu Kr36+ ions and as target a Ni microcapillary. For the fraction of the ion beam that does not suffer any charge exchange, the energy loss is strongly correlated with the scattering angle. The distance-dependent stopping power and thereby the surface dielectric properties of the capillary material can be probed in detail.

In this paper, we present recent activities at the Tokyo EBIT after giving an overview of the present status of the devices. We have been studying dielectronic recombination processes by means of several techniques. In addition to X-ray observations and charge abundance observations, 2-photon observations have been recently used to study DR processes which emit two photons successively (but practically simultaneously). Recent efforts on spectroscopic work are mainly concentrated on Fe and W ions, which are relevant to astrophysical and fusion plasmas. Several spectrometers that can cover a wide range of wavelength, such as visible, EUV, and X-rays, were used for accumulating useful data for plasma diagnostics applications. HCI-surface collision processes were studied using ions extracted through the beam line, that has recently been modified. Very highly charged ions up to Bi81+ were used for studying the effect of huge potential energy.

Recombiant human telomerase reverse transcriptase (hTERT)-human IL-18(hIL18) was constructed to investigate its expression and biological function in eukaryotic cells. DCs transfected with hTERT-IL18 acquired stronger telomerase activity and were able to elicit an hTERT-specific cytotoxic T lymphocyte CTL response in vitro.hIL-18 gene fragment was amplified by polymerase chain reaction (PCR) and TA cloned. The hIL-18 gene was then subcloned into eukaryotic expression vector pcDNA3.1(+) containing human TERT via a linker. The sequence of gene fusion was confirmed using both restrictive enzyme digestion and DNA sequencer. The expression vector with gene fusion was transfected into 3T3 cell line with Lipofectamine 2000. ELISA, Western blot, immunofluorescence stain were performed to determine the expression properties of hTERT-hIL18 in 3T3 cells. Its biological effect on the anti-apoptosis was measured by Flow cytometry and its effect on INF-gamma expression was determined using ELISA. After preparation of dendritic cells, hTERT-hIL18, hTERT, hIL-18 expression vectors were transfected into DCs respectively by electroporation to generate hTERT-specific DCs lines. The peripheral blood mononuclear cells PBMCs were stimulated with different DCs lines to create specific CTL. The response of target cell (leukemia cell line-K562 cell) to hTERT-specific CTL was evaluated by LDH release assay.The human IL-18 gene fragment was amplified from the human mononuclear cells and was inserted into pcDNA3.1(+)/hTERT vector successfully. The correct sequence was proved by both restrictive enzyme digestion and sequencing. The correct open reading frame was also verified. Fusion protein of hTERT-hIL18 was effectively expressed in eukaryotic cells, which was detected by both Western-blotting and immunofluorescence stain. The expressed recombinant fusion protein induced similar levels of INF-gamma to that of native IL-18 protein. FCM assay showed that the transfected fusion protein inhibited the apoptosis, which was consistent with the effects of hTERT as a universal tumor associated antigen. CTL assay shows that hTERT- hIL18 and hTERT gene-transfected DCs stimulated T-cell responses that recognized and lysed tumor target cells of high hTERT expression, whereas DCs transfected with hIL-18 gene didn't induced the response of tumor targets lyses.The Recombinant hTERT- hIL18 fusion protein had both biological activity of hTERT and hIL-18, indicating that this rationally designed protein can be further developed as novel tumor therapeutics. DCs transfected with hTERT-IL18 gene were capable of eliciting a stronger hTERT-specific CTL response in vitro.

We demonstrate that the structure of the outermost orbitals of oxygen and nitrogen can be observed in the angular distribution of coincident ion pairs generated by the double ionization of these molecules by 8 fs laser pulses. We do this by establishing that these ions emerge from well defined excited electronic states of O2+2 and N2+2 respectively and that they are produced dominantly through a process which involves electron rescattering. The angular distributions of the ions from the two targets are very different, reflecting the different structures of the outermost orbitals of the two molecules.

We have studied the $4d$ photoabsorption process of ${\mathrm{Eu}}^{+}$ ions by the linear-density-response theory with the density-functional theory and an optimized effective potential and self-interaction correction. Different from the recent experimental observation, which found that the $4d$ photoabsorption spectrum of ${\mathrm{Eu}}^{+}$ ions is almost the same as that of neutral Eu atoms, our calculated $4d$ photoabsorption spectrum of ${\mathrm{Eu}}^{+}$ ions shows many sharp and window resonances, which do not appear in case of neutral Eu atoms. The discrepancies between the experimental observation and our calculation are due to the experimental energy resolution. The convoluted spectrum with the experimental energy resolution is in good agreement with the experimental observation. Moreover, we predict the $4d$ photoabsorption spectra with several given energy resolutions, which call for a further higher-resolution experiment.

Electron energy loss spectra of the sulfur 2p, 2s and oxygen is inner-shells of SO2 and the nitrogen is and oxygen is inner-shells of NO2 have been obtained at high energy resolution (0.046-0.090 eV fwhm) under conditions of high impact energy (1-3.7 keV) and forward scattering. The measurements are compared with multichannel quantum defect theory calculations of the transition energies and dipole oscillator strengths. The experimental and calculated results are also compared with literature reports of measurements using synchrotron radiation.