Abstract: For generation and delivery of ions from an ionization chamber through an ion entrance orifice to a mass analyzer operating at high vacuum, high pass ion filtration is effected within the ionization chamber by application of electrical potentials to an electrode associated with the ion entrance orifice and to an electrode between the ionization region and the ion entrance orifice to create a retarding electric field upstream from the ion entrance orifice. The retarding electric field hinders the movement to the ion entrance orifice of ions having drift velocities below a lower limit, and as the retarding voltage gradient is made steeper, the lower limit increases.

Abstract: A method and system for economically packaging microarrays into sealed reaction chambers and storage vessels. A pocket strip is manufactured as a linear sequence of pockets, or wells, into which microarrays are positioned. A cover strip is then heat sealed to the upper surface of the pocket strip to create a linear sequence of sealed reaction chambers or storage vessels each containing a microarray. Mechanical features or optical features are included along the length of the pocket strip to facilitate mechanical translation and positioning of microarrays embedded within the microarray strip. Septa are affixed to, or embedded within, the cover strip to provide resealable ports through which solutions can be introduced into, or extracted from, the reaction chambers.

Abstract: A method of using a vector network analyzer (VNA) for coordinated Voltage Standing-Wave Ratio (VSWR) and Time Domain Reflectometry (TDR) measurement includes configuring the VNA for identifying discontinuities correlated to a VSWR lobe. In some embodiments, the method includes identifying a largest VSWR lobe in a frequency band of interest, using phase data associated with an S11 scattering parameter to find the correct electrical delay required to align Low Pass Step Transform data, and configuring the Low Pass Step Transform span and center time to align coherent inductive and capacitive discontinuities relative to grid lines of a TDR display. In some embodiments, the method is automated.

Abstract: A mass spectrometer having an ionization source, a ion trap mass analyzer, an ion guide and gating apparatus between the ion guide and the ion trap. The gating apparatus includes sealing apparatus. A stream of ions from the ion source are guided to through the gating apparatus in pulses to the ion trap. The number of ions in each pulse are controlled by the scaling apparatus.

Abstract: A network analyzing apparatus (100) and method for analyzing the network properties of a device under test (20) to which modulated signals are applied including modulating data contained in output signals (10) of the device under test (20), generating modulated signals (140) based on demodulated data and setting data supplied in advance, outputting the modulated signals as reference signals, and analyzing (150) the network properties of the device under test (20) by comparing or referencing the output signals of the device under test and these reference signals.

Abstract: An optical property of a device under test is determined from a detected DUT response signal, or a signal derived therefrom, whereby the DUT response signal represents a signal response of the DUT in response to a composite signal or a signal derived from said composite signal. The composite signal comprises superimposed signals delayed with respect to each other.

Abstract: Disclosed is a novel electrical probe that stores probe-specific information. A probe implemented in accordance with the invention includes a processor, memory, and a communications interface. Probe-specific information such as a probe identifier and/or calibration parameters that affect the true value of a measurement are stored in the probe memory. The probe-specific information may be retrieved by the processor from the probe memory via the communications interface.

Abstract: In one embodiment, a method for reducing signal noise in a relay having pass-through and attenuator circuits which are alternately closed by operation of an armature assembly of the relay is disclosed. In accordance with the method, the armature assembly is provided with a grounding portion. The grounding portion of the armature assembly is oriented to make contact with the pass-through circuit when the attenuator circuit is closed, but not when the pass-through circuit is closed.

Abstract: A method of data acquisition for a digital instrument having a bandwidth. The method includes receiving a signal and associated trigger. Using that trigger, a plurality of signal values is sampled at multiple time intervals to create an acquisition record representing a continuous fractional segment of the signal. The plurality of samples meets the Nyquist requirement for the bandwidth but is in error according to at least one known error mechanism. The acquisition record is then processed with DSP techniques to produce a compensated acquisition record corrected for the at least one known error mechanism. Each associated compensated acquisition record is incorporated into a result acquisition record as a segment thereof corresponding to a continuous fractional segment of the signal whose signal values were sampled in an associated instance. An additional signal and additional associated trigger are received. The above steps are then repeated for the additional signal and additional associated trigger.

Abstract: A protocol sleuthing system according to the present invention for load testing a network server includes a computer configured to interconnect with the network server, a protocol engine stored in and implemented by the computer and operative to generate a plurality of synthetic users, to generate a synthetic transaction in accordance with a specified protocol, and to cause each of the plurality of synthetic users to sequentially implement a plurality of the synthetic transactions with the network sever for load testing thereof, a configuration file connected to the protocol engine that includes variables required to generate the synthetic transaction, information that defines the behavior of the plurality of synthetic users implementing the synthetic transaction, and information that defines the number of synthetic users to be created by the protocol engine, and a module that is operative to monitor each of the plurality of synthetic transactions implemented by each of the plurality of synthetic users with t

Abstract: The present invention provides methods for analyzing a peptide or peptides of interest in a protein sample using a combination of a relatively generic isotope tag with a decoupled selection process, allowing simplified customization of the application with a single reagent. These methods comprise providing a first and a second protein sample; labeling the first protein sample with a first Universal Peptide Isotope Tag (U-PIT) reagent and the second protein sample with a second U-PIT reagent; separating the peptide of interest from the combined first and second protein samples; and determining the relative amount of the first U-PIT reagent and the second U-PIT reagent bound to the peptide or peptides of interest. The U-PIT label of the present inventive methods has the following general formula A-B-C wherein A is a nucleophilic reactive group, B is a detectable moiety that can be isotopically labeled, and C is a charge replacement group.

Abstract: Methods and compositions for detecting cross-contamination between samples contacted with different arrays of a multi-array substrate are provided. The methods involve contacting sample to arrays of a multi-array substrate that contains cross-contamination probes in each of its arrays, and evaluating the resultant sample contacted arrays for cross-contamination between the samples. In many embodiments, the arrays of the multi-array substrate contain a set of cross-contamination probes for a corresponding set of cross-contamination targets in the sample(s). Kits and systems are provided for performing the invention. The subject methods may be used in a variety of different applications, such as gene expression analysis, DNA sequencing, mutation detection, as well as other genomics and proteomics applications.

Abstract: The present invention relates to an apparatus and to a method of measurement of optical loss of a DUT having a first end and a second end, comprising the steps of: coupling an optical signal into the first end of the DUT, measuring the optical power of the optical signal by a first detector, reflecting the optical signal at the second end of the DUT to send back a reflected optical signal into the DUT, measuring a reflected optical power of the reflected optical signal by a second detector, evaluating a two-way optical loss on the basis of measurements of the first and the second detectors.

Abstract: A calibration technique is presented for calibrating non-reference indirect measurement systems with respect to a reference indirect measurement system. A reference map function filling procedure fits a reference map function based on known values of a parameter of interest associated with reference calibration samples and corresponding reference values associated with the reference calibration samples. A correction function fining procedure fits a correction function based on reference values for calibration samples measured on or simulated for the reference indirect measurement system and corresponding values measured on the non-reference indirect measurement system. During normal use, the non-reference indirect measurement system obtains measurements, corrects the measurements using the correction function, and estimates the parameter of interest of the object of interest using the reference map function based on the corrected measurements.

Abstract: A spectrum analyzer used for making a spectrum emission mask measurement reorganizes execution of the measurement so that all frequency bands to be measured at the same resolution bandwidth are measured in a single sweep, extending between the extreme frequency limits of those bands, thereby avoiding setup delays involved in specifying successive measurements for each band individually. Portions of each measurement which correspond to frequency bands to be measured at the respective resolution bandwidth of that measurement are extracted, resized as necessary, and assembled into a complete spectrum measurement.

Abstract: An optical fiber device with reduced thermal sensitivity comprises a first optical fiber arm having a first composite coefficient of thermal expansion and a first length and a second optical fiber arm having a second composite coefficient of thermal expansion and a second length. A ratio of the first and second lengths inversely matches a ratio of the first and second composite coefficients of thermal expansion to minimize thermal sensitivity in the device.

Abstract: A multi dynode device (MDD) for electron multiplication and detection and a hybrid detector using the MDD have high peak signal output currents and large dynamic range while preserving the time-dependent information of the input event and avoiding the generation of significant distortions or artifacts on the output signal. The MDD and hybrid detector overcome saturation problems observed in conventional hybrid detectors by providing a unique electron multiplier portion that avoids the path-length differences. The MDD and hybrid detector can be used in mass spectrometry, in particular, time-of-flight mass spectrometry. The MDD comprises a plurality of dynode plates arranged in a stacked configuration. Each dynode plate in the stack has a plurality of apertures for cascading secondary electrons through the stack. Each aperture comprises a mechanical bias or offset with respect to the apertures in adjacent plates. The offset is such that the electrons will impact with one or more of the dynode plates.

Abstract: Methods, devices and apparatus are disclosed for carrying out multiple chemical reactions, such as in situ synthesis of polynucleotides, on a surface comprising an array of discrete sites. Molecules are deposited at a predetermined number of the discrete sites on the surface for reaction at the discrete sites. The surface is positioned relative to an outlet of a fluid ejection device, which is activated to dispense a small volume of a fluid through the outlet to the surface to provide uniform coating of a continuous region of the surface comprising a multiple of the discrete sites. The fluid is dispensed as uniform particles having a diameter such that the uniform particles form a sheet to coat the continuous region of the surface. In one embodiment of the present invention, liquid is dispensed as uniform particles through a fluid ejection device activated by means of ultrasonic energy. The invention has particular application to the in situ synthesis of polynucleotides in arrays on a surface.

Abstract: A system for forming an image of an object. The system includes a first scanning x-ray source for generating x-rays that diverge from a source point along a first scan path, the point being variable and determined by an input signal provided by a controller. A plurality of x-ray detectors are positioned with respect to the first scan path and are readout by the controller. A conveyor moves the object relative to the first scanning x-ray source and the plurality of x-ray detectors. The object is divided into a plurality of voxels, and the x-ray detectors are positioned such that x-rays pass through each voxel and arrive at one of the detectors when the source point is located at a plurality of points along the first scan path. The controller preferably generates a three-dimensional representation of the object from the x-ray measurements.

Abstract: For determining a signal response characteristic of a device, a first signal is varied with a first function of time and simultaneously a second signal is varied with a second function of time, wherein the first function is different from the second function. The first and second signals are coupled to the device, wherein the device is exposed to a time-dependent disturbance signal. A signal response is received from the device in response to the first and second signals and the time-dependent disturbance signal. The signal response characteristic is derived by analyzing the received signal response in conjunction with the first and second signals, or a signal derived therefrom, and at least partially removing the time-dependent disturbance signal using the received signal response and the first and second signals, or a signal derived therefrom.