Abstract: Thermal isolation chambers that can be used to heat or cool a chromatography column are described. Certain configurations include at least one plate and an insulative barrier. The plate and insulative barrier can form a cyclical air flow path such that air in the cyclical air flow path can be provided to a chromatography column to remove heat from the chromatography column. The heat can be transferred to the plate. Systems including the thermal isolation chambers, and methods of using the thermal isolation chambers to perform chromatographic separations are also described.

Abstract: Magnetic couplers and sample introduction devices including them are described. In certain configurations, a sample introduction device can include a magnetic coupler that can be used to hold down a sampling device to permit introduction of an analyte sample from the sampling device to an instrument or another component. Systems including the magnetic couplers, and methods and devices to produce them are also described.

Abstract: Magnetic couplers and sample introduction devices including them are described. In certain configurations, a sample introduction device can include a magnetic coupler that can be used to hold down a sampling device to permit introduction of an analyte sample from the sampling device to an instrument or another component. Systems including the magnetic couplers, and methods and devices to produce them are also described.

Abstract: A duckbill valve assembly includes a duckbill valve and a spring member. The duckbill valve has a longitudinal axis, a lateral axis transverse to the longitudinal axis, and opposed proximal and distal ends spaced apart along the longitudinal axis. The duckbill valve defines a valve direction extending from the proximal end to the distal end. The duckbill valve includes a first port at the proximal end, and first and second opposed sidewalls. The first and second sidewalls taper inwardly toward one another in the valve direction to form a duckbill structure. The duckbill structure includes a slit proximate the distal end. The duckbill valve is transitionable from a closed position, wherein the slit is closed, and an open position, wherein the first and second sidewalls are laterally separated proximate the slit to form a second port. The spring member includes a spring leg disposed laterally adjacent the first side wall.

Abstract: A duckbill valve assembly includes a duckbill valve and a spring member. The duckbill valve has a longitudinal axis, a lateral axis transverse to the longitudinal axis, and opposed proximal and distal ends spaced apart along the longitudinal axis. The duckbill valve defines a valve direction extending from the proximal end to the distal end. The duckbill valve includes a first port at the proximal end, and first and second opposed sidewalls. The first and second sidewalls taper inwardly toward one another in the valve direction to form a duckbill structure. The duckbill structure includes a slit proximate the distal end. The duckbill valve is transitionable from a closed position, wherein the slit is closed, and an open position, wherein the first and second sidewalls are laterally separated proximate the slit to form a second port. The spring member includes a spring leg disposed laterally adjacent the first side wall.

Abstract: Embodiments are directed to establishing caches that provide authoritative domain name system (DNS) answers to DNS requests. In one scenario, a computer system establishes a cache that stores authoritative DNS answers to DNS queries. The cache corresponds to a specified DNS zone that includes authoritative DNS answers for a subset of DNS queries. The cache is configured to store the authoritative DNS answers for at least a specified period of time during which the authoritative DNS answers are updatable. The cache then receives an update indicating that at least one cached DNS answer is out-of-date and the computer system purges the out-of-date DNS answer from the cache, ensuring that the cache continually provides authoritative DNS answers for DNS queries assigned to the specified DNS zone.

Abstract: A method and system for pointing a Internet user requesting access to content on a particular web site to one of a plurality of content servers associated with that web site based on one or more cost measurements associated with serving said content. The identification of the web site is mapped to the content servers associated with that web site. The user's IP address is then mapped to a particular content server based on a cost function and the IP address of the selected content server is provided to the user.

Abstract: A Private Network Access Point (PNAP) packet switched network is provided where two customers connected to the same PNAP exchange traffic through the PNAP without transiting over the backbones of the Internet. In addition, a multi-homed customer connected to the PNAP is provided with access to the PNAP optimized routing table so that the customer will also have the ability to know the best route for a particular destination. In this way, if a multi-homed customer connected to a particular National Service Provider (NSP) to which a destination is also connected, the PNAP customer can use the PNAP information regarding the NSP to send the information to the destination through that commonly connected NSP in the most direct fashion.