Abstract: The disclosure relates to a thermal switch system and application thereof in improving yield of amino acid, and particularly relates to a method for improving the yield of amino acid by regulating intracellular metabolic flux distribution using the thermal switch system, which belongs to the technical fields of genetic engineering and microbial fermentation. The system rebalances metabolic flux between pyruvate and oxaloacetate by controlling heterologous expression of pyruvate carboxylase and in combination with chemical properties that oxaloacetate is temperature-sensitive and easy to decarboxylate, and dynamically regulates a central metabolic pathway to ensure the supply of reducing cofactors, so as to promote the production of L-threonine. Temperature-controlled threonine-producing strains TWF106/pFT24rp and TWF113/pFT24rpa1 obtained in the disclosure have threonine molar conversion rates of 111.78% and 124.03% respectively.

Abstract: An optical system for imaging. The optical system includes light emitting diodes to provide light of predetermined wavelengths. The optical system further includes a charge-coupled device to receive the light emitted by one or more light emitting diodes and reflected by an object for fluorescence imaging of the object. The optical system additionally includes a broadband light source to provide broadband light. Furthermore, the optical system includes a spectrometer to receive the broadband light emitted by the broadband light source and reflected by the object for visible-near infrared-shortwave infrared spectroscopy of the object. Additionally, the optical system includes a hyperspectral camera to receive the broadband light emitted by the broadband light source and reflected by the object for hyperspectral imaging of the object as well as a controller coupled to the light emitting diodes, the broadband light source, the charge-coupled device, the spectrometer and the hyperspectral camera.

Abstract: A method of generating a layout data file for a metasurface device is disclosed. At a radial position of a metasurface device, the method determines a primitive cell of a first level having a metasurface feature pattern that is repeated around an arc corresponding to a circumference at the radial position. The method generates metasurface structures of higher levels. Each metasurface structure of a higher level includes multiple references to a structure or a primitive cell of a next lower level. The method stores at least a portion of a layout of the metasurface device to a layout data file. The layout includes references to metasurface structures of two or more of the higher levels.

Abstract: There is provided a lens for use in a human or animal body, the lens comprising a metasurface configured to modulate incident light, wherein the metasurface is composed of at least one light transmissive biomaterial. Also provided is a method of making the lens.

Abstract: A collection of optical sub-elements can be arranged sequentially, such that they share a common optical axis through which light propagates. Each of these optical sub-elements can alter a phase, an amplitude, or a polarization of incident light, by virtue of its surface curvature, such as, for example, in a refractive optical element, or using microscale and nanoscale structures, such as, for example, in a diffractive optical element. One or more of these optical sub-elements can be rotated to tune one or more parameters, such as focal power, of the complete device.

Abstract: An electrically-variable optical device includes a planar optical element (POE) and at least one electromechanical layer. The POE includes at least one optical layer. The at least one electromechanical layer is configured to spatially deform the POE to change an optical parameter of the POE. The at least one electromechanical layer may include a dielectric elastomer actuator (DEA) which includes electrodes and an elastomeric spacer between the electrodes. An electric field may be introduced between the electrodes to deform the spacer, which in turn deforms the POE.

Abstract: A method of fabricating an optical device and the associated optical device are disclosed. The optical device includes a metasurface and a substrate that are integrally formed by the same materials. The method comprises: forming a photoresist mask on a substrate, the photoresist mask defining a metasurface pattern based on an optical profile of a target optical device; generating metasurface features on the substrate, by etching away a portion of the substrate that is not covered by the photoresist mask; and producing the target optical device having the metasurface features, by removing the photoresist mask, wherein the metasurface features include a portion of a material of the substrate.

Abstract: A method of generating a layout data file for a metasurface device is disclosed. At a radial position of a metasurface device, the method determines a primitive cell of a first level having a metasurface feature pattern that is repeated around an arc corresponding to a circumference at the radial position. The method generates metasurface structures of higher levels. Each metasurface structure of a higher level includes multiple references to a structure or a primitive cell of a next lower level. The method stores at least a portion of a layout of the metasurface device to a layout data file. The layout includes references to metasurface structures of two or more of the higher levels.

Abstract: A method and device for playing audio are provided. The method for playing audio includes the following steps: acquiring audio playing information corresponding to an audio playing instruction when the audio playing instruction is received (S10); determining whether audio data obtained after an audio file corresponding to the audio playing information is decoded is stored in a preset storage location (S20); and if yes, invoking the audio data for audio playing (S30).

Abstract: The present invention provides a method for storing a streaming media file in a mobile terminal, the method comprising: starting a streaming media transmission; storing a streaming media file in the background, and marking the playback position of the streaming media file; setting the stored streaming media file as a hidden file, and/or encrypting the stored streaming media file. The present invention also provides a system for storing a streaming media file in a mobile terminal. Via the method and the system, the streaming media file can be directly stored on the mobile terminal, and can be flexibly and smoothly watched by users, without influencing the charge of operators at the same time. Thus, the copyrights of the Audio/Video (A/V) files can be protected, and the service promotion of the operators can be more beneficial.

Abstract: The disclosure provides an encryption method for a television service of a mobile terminal, a mobile terminal and a server. The method comprises: a mobile terminal ordering and obtaining a program that has not been subscribed; the mobile terminal encrypting the program to shield a part of data of the program; and the mobile terminal playing the program that is encrypted. The encryption method for the television service of the mobile terminal, the mobile terminal and the server provided in the disclosure can encrypt the program, which is ordered but has not been subscribed by the user, at the mobile terminal side or the server side so as to play the program after shielding a part of data of the program, thus certain experience can be enjoyed by the user, and the content of the program is protected.