Abstract: A control circuit for an isolated power supply is disclosed, the control circuit includes a secondary-side drive signal generator, a secondary-side transistor switch turn-off detector and a primary-side control signal generator. The primary-side control signal generator is configured to: determine a second turn-on instant referring to an turn-off instant of the secondary-side synchronous rectification transistor from the turn-off acknowledgement signal; determine a first turn-on instant referring to a supposed turn-on instant for the primary-side transistor switch from the feedback signal of the output voltage of the isolated power supply; and determine the turn-on instant for the primary-side transistor switch from the second turn-on instant or the first turn-on instant whichever is later, and responsively generate the primary-side transistor switch control signal.

Abstract: A device for preparing ultra-high purity zinc based on intelligently-controlled zone melting, including a slide platform connected with a screw through a servo control system to control movement of a heating-cooling device. A quartz tube is provided inside an induction heater to protect a melting zone. An infrared thermometer is connected to the heater, and configured to monitor temperature within the melting zone, and control power of the heater. A ring magnetic stirrer with non-contact circumferential rotation cooperates with coil to stir zinc melt. A water-cooling copper jacket is connected to two ends of the heater to cool a zinc bar, and its water inlet and outlet are connected with a water chiller. The infrared thermometer monitors temperature of the zinc bar and controls water flow of the cooling system. A lifting device is connected with a base cabinet to change inclined angle of the zinc bar.

Abstract: Isolated power supply control circuits, isolated power supply and control method thereof are disclosed, the control circuit for controlling an isolated power supply includes a secondary-side control signal generator and a primary-side control signal generator. The secondary-side control signal generator produces a secondary-side transistor switch control signal containing information about a turn-off instant of a secondary-side synchronous rectification transistor, which serves as a second turn-on instant. The primary-side control signal generator derives, from a feedback signal, a supposed turn-on instant for a primary-side transistor switch, which serves as a first turn-on instant. The primary side turn-on signal generator further derives a turn-on instant for the primary-side transistor switch from the second or first turn-on instant whichever is later and responsively generates a primary-side transistor switch control signal.

Abstract: This invention generally relates to the field of vitamin D detection. In particular, the invention provides novel methods and kits for assaying a vitamin D moiety in a sample such as a biological fluid.

Abstract: Provided are methods of culturing cancer stem cells in vitro, where the cancer stem cells have been obtained from the peripheral blood of a patient, and methods of using the cultured cancer stem cells in a xenograft model of cancer and for in vivo and in vitro screening of test compounds. Also provided is an enriched population of cancer stem cells obtained from the peripheral blood of a patient.

Abstract: The present invention provides novel methods for determining the presence or amount of a hydrolytic enzyme in a sample, based on novel substrates for the enzymes, and also provides compositions and methods that provide highly sensitive assay methods for such hydrolytic enzymes.

Abstract: The present invention provides novel methods for determining the presence or amount of a hydrolytic enzyme in a sample, based on novel substrates for the enzymes, and also provides compositions and methods that provide highly sensitive assay methods for such hydrolytic enzymes.

Abstract: The present invention provides novel methods for determining the presence or amount of a hydrolytic enzyme in a sample, based on novel substrates for the enzymes, and also provides compositions and methods that provide highly sensitive assay methods for such hydrolytic enzymes.

Abstract: The present invention provides methods for assaying a vitamin D moiety in a sample, using a water miscible organic solvent, a specific binding partner that specifically binds to said vitamin D moiety, the binding partner being different from a natural vitamin D binding protein for the vitamin D moiety, and a water soluble polymer that facilitates binding between the specific binding partner and the vitamin D moiety. Kits and reaction mixtures for assaying a vitamin D moiety in a sample are also provided.

Abstract: The present invention provides novel methods for determining the presence or amount of a hydrolytic enzyme in a sample, based on novel substrates for the enzymes, and also provides compositions and methods that provide highly sensitive assay methods for such hydrolytic enzymes.

Abstract: The invention relates to a rapid, sensitive method to obtain a gene expression profile from a target cell population in a blood sample. The target cells can be circulating tumor cells. Disclosed are methods and kits for obtaining such profiles.

Abstract: Nitroxide mediated free radical polymerization of vaporized vinyl monomers, including acrylic acid (AAc), styrene (St), N-2-(hydroxypropyl)methacrylamide (HPMA) and N-isopropyl acrylamide (NIPAAm), on silicon wafers is demonstrated. FTIR, ellipsometry and contact angle goniometry were used to characterize the chemical structures, thickness and hydrophilicity of the films. The growth of film is linearly proportional to its reaction time, leading to the easy and exact control of polymer film thickness from nanometers to submicrons. The capability of polymerizing various monomers allows us to fabricate various functional polymer brushes. The reversible thermo-responsiveness of a 200 nm thick grafted poly(NIPAAm) film in aqueous solution is demonstrated with over 50% change in thickness at its lower critical solution temperature. A tri-block copolymer of poly(AAc)-b-polySt-b-poly(HPMA) is successfully synthesized, proving the renewability of TEMPO-mediated polymerization at vapor phase.

Abstract: Nitroxide mediated free radical polymerization of vaporized vinyl monomers, including acrylic acid (AAc), styrene (St), N-2-(hydroxypropyl) methacrylamide (HPMA) and N-isopropyl acrylamide (NIPAAm), on silicon wafers is demonstrated. FTIR, ellipsometry and contact angle goniometry were used to characterize the chemical structures, thickness and hydrophilicity of the films. The growth of film is linearly proportional to its reaction time, leading to the easy and exact control of polymer film thickness from nanometers to submicrons. The capability of polymerizing various monomers allows us to fabricate various functional polymer brushes. The reversible thermo-responsiveness of a 200 nm thick grafted poly(NIPAAm) film in aqueous solution is demonstrated with over 50% change in thickness at its lower critical solution temperature. A tri-block copolymer of poly(AAc)-b-polySt-b-poly(HPMA) is successfully synthesized, proving the renewability of TEMPO-mediated polymerization at vapor phase.

Abstract: A delivery system that releases a diagnostic marker or therapeutic agent in a manner sensitive to the concentration of urease in a physiological compartment, particularly the gastrointestinal tract, and methods of use.