Fabrication of p-Si/beta-FeSi2/n-Si double-heterostructure light-emitting diode by molecular beam epitaxy

We have fabricated p-Si/beta-FeSi(2) film/n-Si double-heterstructure (DH) light-emitting diodes (LEDs) on Si(111) substrates by molecular beam epitaxy (MBE). It was found that both the thickness of an undoped Si overlayer and subsequent annealing temperature were key parameters in preventing the aggregation of the beta-FeSi(2) film and the successful formation of a Si/beta FeSi(2) film/Si DH LED on Si(111). A 1.6 mu m electroluminescence (EL) was realized at room temperature (RT) at a current density higher than 78 A/cm(2) by increasing the thickness of the beta-FeSi(2) active region from 90 nm to 250 nm, suggesting that there exist numerous defects at Si/beta-FeSi(2) heterointerfaces

Growth and characterization of Si-based light-emitting diode with beta-FeSi2 active region by molecular beam epitaxy

Si p-n junction light-emitting diodes with beta-FeSi2 particles and with a beta-FeSi2 continuous film active region were grown on Si(001) and Si(111) substrates, respectively, by molecular beam epitaxy and the electroluminescence properties were investigated

Impact of p38 mitogen-activated protein kinase inhibition on immunostimulatory properties of human 6-sulfo LacNAc dendritic cells

p38 Mitogen-activated protein kinase (MAPK) plays a crucial role in the induction and regulation of innate and adaptive immunity. Furthermore, p38 MAPK can promote tumor invasion, metastasis, and angiogenesis. Based on these properties, p38 MAPK inhibitors emerged as interesting candidates for the treatment of immune-mediated disorders and cancer. However, the majority of p38 MAPK inhibitor-based clinical trials failed due to poor efficacy or toxicity. Further studies investigating the influence of p38 MAPK inhibitors on immunomodulatory capabilities of human immune cells may improve their therapeutic potential. Here, we explored the impact of the p38 MAPK inhibitor SB203580 on the pro-inflammatory properties of native human 6-sulfo LacNAc dendritic cells (slanDCs). SB203580 did not modulate maturation of slanDCs and their capacity to promote T-cell proliferation. However, SB203580 significantly reduced the production of pro-inflammatory cytokines by activated slanDCs. Moreover, inhibition of p38 MAPK impaired the ability of slanDCs to differentiate naïve CD4(+) T cells into T helper 1 cells and to stimulate interferon-γ secretion by natural killer cells. These results provide evidence that SB203580 significantly inhibits various important immunostimulatory properties of slanDCs. This may have implications for the design of p38 MAPK inhibitor-based treatment strategies for immune-mediated disorders and cancer

Time-resolved photoluminescence study of Si/beta-FeSi2/Si structures grown by molecular beam epitaxy

Si/beta-FeSi2 particles/Si(001) and Si/beta-FeSi2 film/Si(111) structures were grown by reactive deposition epitaxy (RDE) and by molecular beam epitaxy (MBE), and time-resolved photoluminescence (PL) was measured from 8 K to 150 K. Both samples exhibited the same PL peak wavelength of 1.54 mum at low temperatures, but the PL decay time of 1.54 mum emission was different, showing that the luminescence originated from different sources. A short decay time (tau similar to 10 ns) was found to be dominant for the Si/beta-FeSi2 particles/Si(001) at low temperatures. In contrast, the decay curve of the Si/beta-FeSi2 film/Si(111) was well fitted by assuming a two-component model, with a short decay time (tau similar to 10 ns) and a long decay time (tau similar to 100 ns)

Nationwide registry of sepsis patients in Japan focused on disseminated intravascular coagulation 2011-2013

Using an energy-resolved mass spectrometer and a time-resolved Langmuir probe, the distribution of bombarding ion energies, their fluxes and energy fluxes at a substrate in an asymmetric bi-polar pulsed DC magnetron have been determined. The discharge was operated in Ar at a pressure of 0.53 Pa with a Ti target and pulsed DC frequencies of 100 and 350 kHz with a range of duty cycles (from 50 to 96%). At 100 kHz, the Ar+and Ti+ time-averaged ion energy distribution functions (IEDFs) reveal three peaks, which are at low energy (<10 eV), in a mid-range (20-50 eV) and at high energy (60-100 eV). We correlate these peaks with distinct phases of the discharge voltage. At 350 kHz the IEDFs show four peaks reflecting a more complex voltage waveform. The low-energy ions are generated in the `on' phase when the plasma potential is typically a few volts above ground. The Ti+ energy spectra show a remnant of the original sputter-neutral energy distribution function. The mid-range ions are produced in the quiescent region of the voltage reverse phase, when the plasma potential is raised globally a few volts above the cathode potential, typically 10-30 V. The high-energy ions are generated in a period of ~0.3 µs, during the discharge voltage overshoot, when the target potential rises to typically over +140 V. However, given the time resolution of the Langmuir probe (0.5 µs), it is not possible to determine if plasma potential is lifted globally to this high potential or only close to the cathode. At 350 kHz, these `fast' ions make up to about a quarter of the total ion flux at the substrate and an upper bound transient power flux of about 2.5 times the maximum delivered in the `on' phase. The total power flux to a substrate in the sustained phase of the discharge is found to increase with frequency and reverse time