Abstract: Provided in the present invention are a 3-hydroxyl-5-pregnane-20-one derivative as shown in formula I or a pharmaceutically acceptable salt thereof, and a pharmaceutical composition comprising the derivative or the pharmaceutically acceptable salt thereof. The derivative or the pharmaceutically acceptable salt thereof or the pharmaceutical composition comprising the above-mentioned derivative or salt of the present invention can be used to prepare a drug for treating a disease caused by abnormalities in the central nervous system.

Abstract: A clamping device for mounting a mobile terminal device to a hot shoe of an image photographing apparatus includes a quick release structure and a clamping assembly. The quick release structure includes a cold shoe fixing piece for connecting to a quick release interface of the hot shoe, and a first locking structure for selectively quickly locking the cold shoe fixing piece to the hot shoe, or quickly unlocking the cold shoe fixing piece from the hot shoe. The clamping assembly is configured to clamp the mobile terminal device, so that the mobile terminal device can be mounted, together with the quick release structure, to a quick release interface of the image photographing apparatus along with the clamping device. This facilitates quick and reliable mounting of the mobile terminal device to the image photographing apparatus, and quick removal of the mobile terminal device from the image photographing apparatus.

Abstract: A follow focus device for a gimbal carrying an image capturing device includes a power assembly connected to the image capturing device, a connection member, and an adjustment member electrically connected to the power assembly. The power assembly is configured to adjust at least one lens parameter of the image capturing device. The connection member is configured to fix the power assembly to the gimbal. The adjustment member generates a control signal to adjust the lens parameter of the image capturing device. The power assembly receives the control signal from the adjustment member and, based on the control signal, rotates a part of the image capturing device to adjust the lens parameter of the image capturing device.

Abstract: A method for improving the uniformity of high-frequency discharge plasma by means of frequency modulation is disclosed. In a plasma discharge chamber, there is a pair of parallel electrodes. A high-frequency power supply is adopted to feed the electrodes. The frequency range of the electromagnetic field is 13.56 MHz˜160 MHz. Discharge gas is input to form plasma. The frequency of the fed-in high-frequency electromagnetic field is under automatic tuning control, and keeps changing cyclically without stop in the course of plasma discharge. The range of the frequency change may fall into either a portion of or the entire range of 13.56 MHz˜160 MHz and makes the locations with higher plasma density on the plane in parallel with the electrodes and in the plasma discharge space changed cyclically. In a time slot longer than one frequency change cycle, the average plasma density between the parallel electrodes is uniform.

Abstract: A method for improving the uniformity of high-frequency discharge plasma by means of frequency modulation is disclosed. In a plasma discharge chamber, there is a pair of parallel electrodes. A high-frequency power supply is adopted to feed the electrodes. The frequency range of the electromagnetic field is 13.56 MHz˜160 MHz. Discharge gas is input to form plasma. The frequency of the fed-in high-frequency electromagnetic field is under automatic tuning control, and keeps changing cyclically without stop in the course of plasma discharge. The range of the frequency change may fall into either a portion of or the entire range of 13.56 MHz˜160 MHz and makes the locations with higher plasma density on the plane in parallel with the electrodes and in the plasma discharge space changed cyclically. In a time slot longer than one frequency change cycle, the average plasma density between the parallel electrodes is uniform.