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Abstract: Peroxisome proliferator-activated receptor (PPAR) γ coactivator 1-α (PGC-1α) is a transcriptional coactivator identified as an upstream regulator of lipid catabolism, mitochondrial number and function. PGC-1α protects neurons against oxidative damage by inducing several members of the mitochondrial antioxidant system such as superoxide dismutase 2 (SOD2) and uncoupling protein 2 (UCP2). Its role in seizure-induced oxidative stress has not been studied. Here we showed that pilocarpine-induced status epilepticus (SE) stimulates the PGC-1α/mitochondrial antioxidant system signaling pathway in the rat hippocampus. Because nitric oxide (NO) is the key factor of mitochondrial biogenesis through the transcriptional induction of PGC-1α, we investigated whether NO is involved in activation of the PGC-1α/mitochondrial antioxidant system after SE. Treatment with the NO synthase (NOS) inhibitor NG-nitro-l-argininemethyl ester (l-NAME) attenuated the increased expression of the PGC-1α/mitochondrial antioxidant system after SE and enhanced oxidative stress. These results suggest that SE can induce the PGC-1α/mitochondrial antioxidant system signaling pathway, which may represent a protective mechanism against SE-induced oxidative stress. Furthermore, NO may positively regulate the mitochondrial antioxidant system by inducing PGC-1α in pilocarpine-induced SE. [Copyright &y& Elsevier]

Abstract: Diamond nucleation on copper (Cu) substrates was investigated by graphite seeding and CO2 laser irradiation at initial stages of the combustion-flame deposition. A graphite aerosol spray was used to generate a thin layer of graphite powders (less than 1μm) on Cu substrates. The graphite-seeded Cu substrates were then heated by a continuous CO2 laser to about 750°C within 1min. It was found that diamond nucleation density after this treatment was more than three times as much as that on the virgin Cu substrates. As a consequence, diamond films up to 4μm were obtained in 5min. The enhancement of diamond nucleation on the graphite-seeded Cu substrates was attributed to the formation of defects and edges during the etching of the seeding graphite layers by the OH radicals in the flame. The defects and edges served as nucleation sites for diamond formation. The function of the CO2 laser was to rapidly heat the deposition areas to create a favorable temperature for diamond nucleation and growth. [Copyright &y& Elsevier]

Abstract: Diamond nucleation and growth in the combustion-flame method were monitored in real time using thermionic emission current from the deposited diamond films. It was observed that the emission current evolved over three periods, the incubation, the fast increase, and the saturation periods. Ball-shaped diamond particles, faceted diamond crystals, and diamond films with well-faceted crystals were formed in the three periods. The current from a diamond-seeded substrate started to increase immediately without an incubation period, confirming that the current is from the diamond. Therefore, the current could be used for real-time monitoring of the diamond nucleation and growth. [Copyright &y& Elsevier]

The transport of particles in a spatially periodic field driven by multiplicative noise is investigated. The probability current shows that the correlation of the noise with the space is an ingredient for the net flux of particles. By two special models, we illustrate the transport induced by the multiplicative noise in the absence of spatial asymmetry. [Copyright &y& Elsevier]

• A newly developed runaway detection system on HL-2M tokamak withn time-resolution of 10 µs. • This diagnostic system is based on the Cherenkov effect, and Al 2 O 3 is chose as the radiator. • The clear experimental evidences of enhanced losses of REs during sawtooth instabilities have been obtained by means of the Cherenkov probe system. An energetic particle diagnostic system based on the Cherenkov effect has been developed to detect the characteristics of runaway electrons (REs) in the HL-2M tokamak. The Cherenkov radiator is a cylinder made of sapphire with a diameter of 5 mm and a height of 10 mm. Its surface is coated with molybdenum film with thickness of 5 µm. The Cherenkov light spectrum which is emitted by REs when they pass through radiator with different energy is simulated by Geant4. Simulation results show that REs with energy above 120 keV can be effectively measured. The A l 2 O 3 radiator is mounted at the end of an adjustable long shaft. The shaft can enter or withdraw from the chamber to optimize the radial position of the radiator. The Cherenkov signal can be transmitted through an optical path to the Silicon Photomultiplier (SiPM) and the sampling frequency of the signal acquisition system is 100 kHz. This probe was installed on the HL-2M device in 2022 and successfully obtained valid data during the autumn experiments. Measurements of the RE losses by the Cherenkov probe have been performed during HL-2M Ohmic discharges. Clear experimental evidences of the enhancement of RE losses during sawtooth instabilities have been obtained by the Cherenkov probe system. A detailed description of the probe system and the first experimental results are reported. [ABSTRACT FROM AUTHOR]

• The trajectory of the fast ions of HL-2M tokamak is simulated. • The probe of the FILP has been designed, and the strike area was obtained. • A comprehensive description of the new FILP system on the HL-2M tokamak. The fast ion loss detector provides information on the pitch angle and gyroradius of the lost fast ions when energetic ion-driven MHD instability occurs. Based on the device's operating parameters, a fast ion loss detector system based on a scintillator detector was designed and developed on the HL-2M tokamak. In this paper, the trajectory of fast ions on HL-2M is simulated by a self-developed program. The detector used in this system is a ZnS: Ag (23×58 mm2) scintillation detector, which can measure the loss of fast ions at large angles. The light signal emitted by the scintillator will be divided into two paths through the spectroscope. One path transmits light signals to a high-speed camera to capture real-time lossless fast ion evolution images. The other path reaches the photomultiplier tube array to measure the loss rate of fast ions. [ABSTRACT FROM AUTHOR]