Abstract: A chimeric lysozyme variant has an improved heat resistance and is encoded by a polynucleotide. A novel chimeric lysozyme sequence is constructed, and high-efficiency expression in a host cell is achieved. The thermal stability of the chimeric lysozyme under the condition of 60° C. is nearly doubled compared to a parental sequence. The chimeric lysozyme variant can be used to prepare product that is antibiotic, for example, animal feed additive containing the chimeric lysozyme variant and an animal feed containing the animal feed additive.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for current-limiting protection of an amplifier, such as a power amplifier in a radio frequency (RF) front-end. One example current-limiting circuit generally includes a node coupled to a current source, a plurality of current-sinking devices coupled to the node, one or more switches coupled between the node and at least one of the plurality of current-sinking devices, and a bias circuit having an input coupled to the node and an output for coupling to an input of the amplifier.

Abstract: The present application provides a load balancing system. In an example, the load balancing system includes a client, a first load balancer coupled to the client, a plurality of security forwarding devices whose load sides are coupled to the first load balancer and forwarding sides are coupled to a second load balancer, the second load balancer, and a server coupled with the second load balancer. In the load balancing system, service traffic resources can be accurately allocated to the target security forwarding device selected by the scheduling algorithm, so as to balance load.

Abstract: A circuit including a radio frequency (RF) amplifier including a transistor configured to receive an RF signal at its control terminal, a capacitor coupled to a first terminal of the transistor, an inductor coupled to a second terminal of the transistor, wherein the capacitor and inductor form a loop from the first terminal to the second terminal, wherein the loop bypasses a parasitic inductance between the second terminal and ground.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for operating a power amplifier. In one example, the apparatus includes a power amplifier configured to amplify an input signal having a frequency to produce a radio frequency (RF) output signal at an output and a harmonic tuning circuit coupled between a power supply and the power amplifier output, the harmonic tuning circuit configured to reduce a current or voltage provided to the power amplifier via a resonance at one or more harmonics of the frequency of the input signal.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for operating a power amplifier. In one example, the apparatus includes a power amplifier configured to amplify an input signal having a frequency to produce a radio frequency (RF) output signal at an output and a harmonic tuning circuit coupled between a power supply and the power amplifier output, the harmonic tuning circuit configured to reduce a current or voltage provided to the power amplifier via a resonance at one or more harmonics of the frequency of the input signal.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for current-limiting protection of an amplifier, such as a power amplifier in a radio frequency (RF) front-end. One example current-limiting circuit generally includes a node coupled to a current source, a plurality of current-sinking devices coupled to the node, one or more switches coupled between the node and at least one of the plurality of current-sinking devices, and a bias circuit having an input coupled to the node and an output for coupling to an input of the amplifier.

Abstract: A circuit including a radio frequency (RF) amplifier including a transistor configured to receive an RF signal at its control terminal, a capacitor coupled to a first terminal of the transistor, an inductor coupled to a second terminal of the transistor, wherein the capacitor and inductor form a loop from the first terminal to the second terminal, wherein the loop bypasses a parasitic inductance between the second terminal and ground.

Abstract: Techniques for efficiently integrating directional coupler circuitry with other circuit elements of an RF front end. In an aspect, one or more inductors of an RF front end filter is incorporated into a first inductor of the directional coupler, and a capacitor is further coupled in parallel with the first inductor. In another aspect, circuitry associated with matching components of the RF front end may further be incorporated into the directional coupler design. Further techniques are provided for coupling directivity tuning elements to a second inductor of the directional coupler to improve the linearity of the coupler over other tuning techniques.