Abstract: IFN-alpha mutants are obtained by substituting Cys for Tyr at position 85 or 86 in existing IFN-alpha. Their polyethylene glycol derivatives with high in vitro antiviral activity and prolonged in vivo half-life are also provided, wherein a polyethylene glycol moiety is covalently bound to the free Cys residue of an IFN-alpha mutant. The preparation methods of PEG derivatives of IFN-alpha mutants and medical compositions comprising the derivatives are also provided. The test results showed that the IFN-alpha mutants of the present invention are ready to prepare and have high activity; their polyethylene glycol derivatives have extended lifetime in the body and low clearance rate.

Abstract: A method for controlling a current flowing through one or more light emitting diodes (LEDs) comprising receiving a Pulse Width Modulation (PWM) control signal, which includes rising and falling edges; receiving a first voltage signal; generating a second voltage signal based on the PWM control signal and the first voltage signal, wherein the second voltage increases gradually in response to one of the rising and falling edges of the PWM signal and decreases gradually in response to the other of the rising and falling edges of the PWM signal; and providing a current to the one or more LEDs, wherein the current varies gradually according to the second voltage.

Abstract: An embodiment of the present invention relates to a method for detection of short circuit conditions in an LED array having one or more LED strings, each of which includes one or more LED devices. The method includes determining a minimum voltage that is the lowest of voltages associated with cathode terminals of the one or more LED strings. The method also includes determining if said minimum voltage is between a lower limit voltage and an upper voltage limit. If said minimum voltage is between the lower limit voltage and the upper voltage limit, then a result of a short circuit testing can be considered valid. Here, the short circuit testing includes comparing a sampled voltage associated with a cathode voltage of one of the LED strings with a short-circuit reference voltage.

Abstract: IFN-alpha mutants are obtained by substituting Cys for Tyr at position 85 or 86 in existing IFN-alpha. Their polyethylene glycol derivatives with high in vitro antiviral activity and prolonged in vivo half-life are also provided, wherein a polyethylene glycol moiety is covalently bound to the free Cys residue of an IFN-alpha mutant. The preparation methods of PEG derivatives of IFN-alpha mutants and medical compositions comprising the derivatives are also provided. The test results showed that the IFN-alpha mutants of the present invention are ready to prepare and have high activity; their polyethylene glycol derivatives have extended lifetime in the body and low clearance rate.

Abstract: The present invention relates to a parallel light emitting diode (“LED”) drive circuit and provides a drive circuit configured to drive a parallel array of LEDs. The drive circuit comprises: a plurality of switches, a plurality of sampling resistors, and a plurality of chopper amplifiers. Each switch is coupled to a respective LED in the LED array. Each chopper operational amplifier configured to receive a reference voltage and a switching control signal and generate an input offset voltage. Each chopper operational amplifier includes a differential amplifier including an input transistor pair and a current mirror transistor pair, of which the electrical positions can be reserved when the switching control signal is switched between a first state and a second state, wherein the offset voltage, which causes the lightness mismatching in a parallel LED circuit, can be cancelled.

Abstract: The present invention relates to a parallel light emitting diode (“LED”) drive circuit and provides a drive circuit configured to drive a parallel array of LEDs. The drive circuit comprises: a switching control signal generator, a plurality of switches, a plurality of sampling resistors, and a plurality of chopper amplifiers. Each switch is coupled to a respective LED in the LED array. Each chopper operational amplifier configured to receive a reference voltage and a switching control signal generated by the switching control signal generator and generate an input offset voltage. Each chopper operational amplifier includes a differential amplifier including an input transistor pair and a current mirror transistor pair, of which the electrical positions can be reserved when the switching control signal is switched between a first state and a second state, wherein the offset voltage, which causes the lightness mismatching in a parallel LED circuit, can be cancelled.

Abstract: The present invention relates to a parallel light emitting diode (“LED”) drive circuit and provides a drive circuit configured to drive a parallel array of LEDs. The drive circuit comprises: a switching control signal generator, a plurality of switches, a plurality of sampling resistors, and a plurality of chopper amplifiers. Each switch is coupled to a respective LED in the LED array. Each chopper operational amplifier configured to receive a reference voltage and a switching control signal generated by the switching control signal generator and generate an input offset voltage. Each chopper operational amplifier includes a differential amplifier including an input transistor pair and a current mirror transistor pair, of which the electrical positions can be reserved when the switching control signal is switched between a first state and a second state, wherein the offset voltage, which causes the lightness mismatching in a parallel LED circuit, can be cancelled.

Abstract: IFN-alpha mutants are obtained by substituting Cys for Tyr at position 85 or 86 in existing IFN-alpha. Their polyethylene glycol derivatives with high in vitro antiviral activity and prolonged in vivo half-life are also provided, wherein a polyethylene glycol moiety is covalently bound to the free Cys residue of an IFN-alpha mutant. The preparation methods of PEG derivatives of IFN-alpha mutants and medical compositions comprising the derivatives are also provided. The test results showed that the IFN-alpha mutants of the present invention are ready to prepare and have high activity; their polyethylene glycol derivatives have extended lifetime in the body and low clearance rate.

Abstract: An embodiment of the present invention relates to a method for detection of short circuit conditions in an LED array having one or more LED strings, each of which includes one or more LED devices. The method includes determining a minimum voltage that is the lowest of voltages associated with cathode terminals of the one or more LED strings. The method also includes determining if said minimum voltage is between a lower limit voltage and an upper voltage limit. If said minimum voltage is between the lower limit voltage and the upper voltage limit, then a result of a short circuit testing can be considered valid. Here, the short circuit testing includes comparing a sampled voltage associated with a cathode voltage of one of the LED strings with a short-circuit reference voltage.

Abstract: The present invention relates to a parallel light emitting diode (“LED”) drive circuit and provides a drive circuit configured to drive a parallel array of LEDs. The drive circuit comprises: a switching control signal generator, a plurality of switches, a plurality of sampling resistors, and a plurality of chopper amplifiers. Each switch is coupled to a respective LED in the LED array. Each chopper operational amplifier configured to receive a reference voltage and a switching control signal generated by the switching control signal generator and generate an input offset voltage. Each chopper operational amplifier includes a differential amplifier including an input transistor pair and a current mirror transistor pair, of which the electrical positions can be reserved when the switching control signal is switched between a first state and a second state, wherein the offset voltage, which causes the lightness mismatching in a parallel LED circuit, can be cancelled.

Abstract: The present invention relates to a parallel light emitting diode (“LED”) drive circuit and provides a drive circuit configured to drive a parallel array of LEDs. The drive circuit comprises: a plurality of switches, a plurality of sampling resistors, and a plurality of chopper amplifiers. Each switch is coupled to a respective LED in the LED array. Each chopper operational amplifier configured to receive a reference voltage and a switching control signal and generate an input offset voltage. Each chopper operational amplifier includes a differential amplifier including an input transistor pair and a current mirror transistor pair, of which the electrical positions can be reserved when the switching control signal is switched between a first state and a second state, wherein the offset voltage, which causes the lightness mismatching in a parallel LED circuit, can be cancelled.

Abstract: IFN-alpha mutants are obtained by substituting Cys for Tyr at position 85 or 86 in existing IFN-alpha. Their polyethylene glycol derivatives with high in vitro antiviral activity and prolonged in vivo half-life are also provided, wherein a polyethylene glycol moiety is covalently bound to the free Cys residue of an IFN-alpha mutant. The preparation methods of PEG derivatives of IFN-alpha mutants and medical compositions comprising the derivatives are also provided. The test results showed that the IFN-alpha mutants of the present invention are ready to prepare and have high activity; their polyethylene glycol derivatives have extended lifetime in the body and low clearance rate.

Abstract: Nucleic acids can be made available for amplification or other treatment after admixture of a sample with specific weakly basic polymers to form a precipitate with the nucleic acids at acidic pH. After removing non-precipitated materials, the pH is then made basic, thereby releasing the nucleic acids from the polymer. This method for preparing specimen samples is simple and quite rapid, and the released nucleic acids can be further treated in hybridization assays or amplification procedures. No surfactant or other cell lysing reagents are employed. The weakly basic polymers are water-soluble and cationic at acidic pH, but neutral in charge at basic pH.

Abstract: Nucleic acids can be made available for amplification or other treatment after admixture of a sample with specific weakly basic polymers to form a precipitate with the nucleic acids at acidic pH. After removing non-precipitated materials, the pH is then made basic, thereby releasing the nucleic acids from the polymer. This method for preparing specimen samples is simple and quite rapid, and the released nucleic acids can be further treated in hybridization assays or amplification procedures. No surfactant or other cell lysing reagents are employed. The weakly basic polymers are water-soluble and cationic at acidic pH, but neutral in charge at basic pH.

Abstract: Nucleic acids can be made available for amplification or other treatment after admixture of a sample with specific weakly basic polymers to form a precipitate with the nucleic acids at acidic pH. After removing non-precipitated materials, the pH is then made basic, thereby releasing the nucleic acids from the polymer. This method for preparing specimen samples is simple and quite rapid, and the released nucleic acids can be further treated in hybridization assays or amplification procedures. No surfactant or other cell lysing reagents are employed. The weakly basic polymers are water-soluble and cationic at acidic pH, but neutral in charge at basic pH.

Abstract: Nucleic acids can be made available for amplification or other treatment after admixture of a sample with specific weakly basic polymers to form a precipitate with the nucleic acids at acidic pH. After removing non-precipitated materials, the pH is then made basic, thereby releasing the nucleic acids from the polymer. This method for preparing specimen samples is simple and quite rapid, and the released nucleic acids can be further treated in hybridization assays or amplification procedures. No surfactant or other cell lysing reagents are employed. The weakly basic polymers are water-soluble and cationic at acidic pH, but neutral in charge at basic pH.