An apparatus and method for differential spectral interferometry comprising providing an interferometer comprising a light source; employing an element to provide a dithered relative phase shift between target and reference arms of the interferometer, detecting output from the interferometer, demodulating signals received from the detector at different multiples of the dither frequencies, generating more than one real-valued interferograms from demodulated signals, and using the real-valued interferograms to obtain the complex spectral interferogram.

1. Field of the Invention (Technical Field)
The present invention relates to the field of full phase interferometry wherein the phase of the interferogram is recovered from only intensity measurements. Applications of the invention include phase-shifting interferometry, Fourier domain optical coherence tomography, and Fourier domain optical coherence reflectometry.
2. Description of Related Art
Note that the following discussion refers to a number of publications by author(s) and year of publication, and that due to recent publication dates certain publications are not to be considered as prior art vis-a-vis the present invention. Discussion of such publications herein is given for more complete background and is not to be construed as an admission that such publications are prior art for patentability determination purposes.
The ability to perform high resolution, subsurface imaging is needed in many fields including biology and medicine (tissue structure and pathology, cell morphology, tumor detection), materials science (composite, ceramic and microstructured materials characterization), and semiconductor device characterization. Application of optical techniques to biological materials is especially difficult because of the absorption and scattering characteristics of tissues. Several optical techniques that provide micrometer scale or better resolution have been applied to biological and medical imaging and each has different strengths and weaknesses. These techniques include confocal and two-photon fluorescence microscopy, confocal Raman spectroscopy, near-field optical microscopy, and optical coherence tomography (OCT), which is a term used for optical coherence reflectometry (OCR) when applied to biomedical imaging. Methods based on fluorescence or Raman scattering can provide high resolution and chemical specificity, but are not as useful for high resolution subsurface imaging because of absorption of either the input or signal wavelengths. On the other hand, OCT and other reflectometry techniques, such as spectral interferometry (SI), can provide structural information in scattering media at depths up to a few millimeters with a spatial resolution of a few micrometers. Imaging through centimeters of tissue can also be performed with reflectometry methods, but with much lower resolution. Since such methods detect reflective or back-scattering sites, they generally do not provide chemical identification. However, they are very useful for elucidating structure in heterogeneous or layered materials—such as skin tissue, for example. Furthermore, techniques like OCT and SI do not require fluorescence tagging, staining, or fixing of the sample.
The present invention is related to a rapid, high resolution optical imaging method and apparatus for, among other applications, clinical and biomedical research problems including studies of tissue response to drugs or radiation exposure, detection of cancerous and precancerous tissues, imaging of venous and arterial structures, and imaging of ocular pathologies. The method and apparatus, which will be referred to as complex differential spectral interferometry (CDSI), is based on the technique called differential spectral interferometry (DSI) described in U.S. Patent Application Publication No. 2004/0239946. The invention significantly improves the performance of DSI by allowing instantaneous acquisition of the full complex spectral interferogram and better resolving of the complex conjugate ambiguity, the major artifact problem of the DSI method. The CDSI method and apparatus can be easily used with fiber optics and can be incorporated into endoscopes, catheters and similar devices for in vivo applications.
Both CDSI and DSI are extensions of spectral interferometry (SI), a low coherence scattering technique, which performs measurements in Fourier domain (or frequency domain), as opposed to time-domain OCT (TD-OCT), which performs measurements in time domain. SI and TD-OCT are Fourier transform analogs. "Spectral interferometry" is also known as "Fourier domain Optical Coherence Tomography," "frequency domain Optical Coherence Tomography," "spectral domain Optical Coherence Tomography," and "Spectral radar." Both SI and TD-OCT have potential for imaging in tissue. Recent work has postulated that SI or Fourier domain OCT (FD-OCT) has the potential to have a large sensitivity advantage over conventional TD-OCT systems. Leitgib et al., Opt. Express 11, p. 889 (2003); Choma et al., Opt. Express 11, p. 2183 (2003); and de Boer et al., Opt. Lett. 28, p. 2067 (2003). However, this work also admits that the improvement in sensitivity is difficult to implement in practice. There are three reasons for the low sensitivity of conventional SI as compared to TD-OCT. First, SI is a DC measurement that causes large amounts of DC and 1/f noise to be integrated into the measured signal. Second, SI has background artifacts (so called autocorrelation terms) that cannot be removed by averaging. Third, SI images obtained from real-valued spectral interferograms suffer form the complex conjugate ambiguity (also known as reflection ambiguity or reflected image ambiguity), an artifact that is inherent to real Fourier transform. Because of this artifact, an SI image obtained from a real-valued interferogram consists of two overlapped images that are symmetrical with respect to the zero phase delay of the interferometer. To avoid ambiguity in interpretation of the image, the zero phase delay plane must be positioned outside of the imaged sample. Thus only one half of the imaging depth range is useful in practice.
An example of the "complex conjugate ambiguity" or "reflected image ambiguity" is shown schematically in FIG. 2. The figure depicts light being scattered from two surfaces of a thick, non-scattering object (glass plate, for example). The "center point" corresponding to zero phase delay of the interferometer is the center of the scan. In the case of TD-OCT, there is no reflection ambiguity about the center of the scan. In other words, the position of all scattering points relative to each other is preserved. In the case of SI, however, there appears to be two points on each side of the center scan. Worse, SI has a large DC background that is difficult to remove; it is a DC measurement with a large 1/f noise component. (The 1/f noise component can also contain sample movement and vibration-all low frequency noise sources.)
To remove the DC and autocorrelation artifacts, Applicants developed the DSI technique. Vakhtin et al., Opt. Lett. 28, p. 1332 (2003). DSI removes the DC component in SI measurements because lock-in or differential detection, phase-locked to a dither in the reference arm, passes detection frequencies only around the dither frequency. All frequencies at DC are removed where the majority of 1/f noise resides. (It should be noted, however, that the detection bandwidth can be quite small even though the detection frequency can be large.) The autocorrelation artifacts are also removed. Thus, DSI allows the greater dynamic range and sensitivity inherent in SI detection to be realized. DSI has additional advantages over conventional TD-OCT that result in a robust instrument suitable for research and clinical settings. These advantages include faster imaging rates and the simplification of the interferometer. However, the basic, single modulation version of DSI does not remove the complex conjugate artifact.
The problem of complex conjugate ambiguity has been addressed using different approaches, including phase-shifting methods, simultaneous detection of the quadrature components of the interferogram by using 3×3 fiber-optic couplers, and separation of the two complex conjugate images by choosing the appropriate carrier frequency in swept-source FD-OCT.
Phase-shifting methods allow acquisition of the complex spectral interferogram to be obtained in a multi-frame sequence. Schmitt and Creath, Appl. Opt. 34, p. 3610 (1995); and Wojtkowski et al., Opt. Lett 27, p. 1415 (2002). A multiple-phase-shift extension of DSI resolves the complex conjugate ambiguity. However, in practice the complex conjugate rejection ratio is limited by accuracy of the phase steps and also by the mechanical stability of the interferometer and the sample during the acquisition time of the frame sequence. Phase-shifting methods are sequential in nature and cannot provide simultaneous acquisition of the quadrature components of the complex spectral interferogram.
The detection of the complex interferogram using 3×3 fiber couplers as phase-shifting elements allows simultaneous detection of the real and imaginary components of the spectral interferogram. Choma et al., Opt. Left. 28, p. 2162 (2003); and Sarunic et al., Opt. Express 13, p. 957 (2005). This requires two separate detectors for acquiring the quadrature components. Slight misalignments in matching the spectrometers (in the case of broadband FD-OCT) and uneven wavelength-dependent splitting ratios in the coupler that lead to imperfect subtraction of the spectra (in the case of swept source FT-OCT) limit the suppression of the complex conjugate artifacts. The reported maximum complex conjugate rejection ratio is 20 dB for broadband FD-OCT and 25 dB for swept source FD-OCT. Sarunic et al., Opt. Express 13, p. 957 (2005).
Choosing the appropriate carrier frequency in swept-source FD-OCT separates the two mirror images and resolves the complex conjugate ambiguity. Zhang et al., Opt. Lett. 30, p. 147 (2005). However, this is not applicable to the parallel implementation of FD-OCT (which involves a broadband light source and detection of the spectral interferograms with an array detector). Also, when the full complex interferogram is not obtained, spectral information is lost.
The present invention, CDSI, improves DSI to better recover complex interferograms and resolve the complex conjugate ambiguity. Compared to other methods of full phase interferometry, the present invention provides a better complex conjugate rejection ratio and allows simultaneous acquisition of the quadrature components of the complex spectral interferogram.
The present CDSI invention has several important advantages over the current state of DSI including more accurate and instantaneous measurement of the complete complex interferogram with higher dynamic range than is possible using TD-OCT methods and possibility of combining spectral and structural imaging into one device. CDSI provides the potential for combining spectral and structure data. While some work has demonstrated that SI can provide some spectral information together with structural information, the best results have indicated that the full complex interferogram is required. Indeed, mathematically this is the case. Work with ultrashort laser pulse measurement (reconstruction of the pulse from spectrograms) indicates that full interferograms will be required to combine spectral and structural information in TD-OCT systems. Thus, only TD-OCT with complete digitization of the interferogram can provide both spectral and structural information together. Normally TD-OCT uses envelope detection which does not record much of the information required to obtain both spectral and structure information. Attempts to record the entire interferogram significantly reduce the dynamic range of the TD-OCT device. Morgner et al., Opt. Lett. 25, p. 111 (2000). In contrast, CDSI recovers the full complex interferogram, which provides the potential of combining both structural and spectroscopic imaging into one device without losing the dynamic range.

Method and apparatus for full phase interferometry


An arm support and positioning assembly is provided that includes a vertical member, an engagement member and a horizontal member having one end engaged with the vertical member through a ball joint assembly and the other end affixed with the engagement member through a wedge lock. The engagement member receives and retains a patient's arm support during the surgical or medical procedures. The vertical member is attached to the clamp support assembly affixed with the operating table. The ball joint assembly includes a first hinge plate, a second hinge plate, and a ball joint having an elongated ball neck on one end and a spherical ball on other end. The ball shape end allows the horizontal member to rotate at a varied angular position with respect to the vertical member thereby providing a greater degree of adjustability to the surgeon.

The present invention relates generally to a limb support and positioning structure used for maintaining a patient's arm in the desired position for surgery thereon. More specifically, the present invention relates to a surgical limb support and positioning structure that allows for the adjustable positioning of the patient's arm during the implementation of a surgical procedure.
Limb support and positioning devices, also referred to as traction devices, are commonly used by surgeons to maintain a patient's limb or extremity in a controlled and elevated position during a surgical procedure. For example, if a person has a broken arm, a traction device may be employed to elevate the arm while the person is reclining on an operating table in order to immobilize and align the arm so that the fracture can be repaired properly. In this regard, numerous devices and structures are currently available in the prior art that are tailored for use as support structures for a limb or the limbs of a patient and particularly for use during the implementation of surgical procedures where it is of extreme importance that the limb or limbs being operated on are immobilized in a desired position in order to insure proper alignment during the procedure.
The difficulty with a great number of the prior art devices is that they are tailored to a shape that provides positioning for only a single procedure and are therefore not useful in other contexts. Further, because of their specialized nature, such devices often do not include any adjustability for the positioning of the limb retained therein. Such devices take the form of bolsters and arm boards that are designed to constrain the forearm of the patient while a medical device is applied to the patient's arm. In these devices there is some degree of adjustability relative to the longitudinal extension of the support and some minor adjustability for supporting the hand. However, the degree of angular adjustment in supporting the forearm, elbow, arm and shoulder is only of relatively limited nature.
In one prior art device, an assembly is provided that is mounted in a stand on the floor or on the base of the surgical table. A supporting rod extends upwardly from beneath the table and supports a secondary member using an articulated joint that in turn engages the patient's hand or forearm in order to support and position the limb. In operation however, the primary support bar is positioned such that it is often in the way of accessing the patient's elbow, requiring instead that the surgeon work around the bar. Further, when the patient is in a supine position and the elbow is in an extended position the bar of the support must be fully extended wherein it hits the patient's body, thereby limiting the overall total extension that is possible. In another prior art device, a rope weight design is used in positioning the patient's arm. However, since the device is applied in a non-sterile fashion, the surgeon is limited in the intraoperative adjustments that can be achieved.
Therefore, although a variety of traction assemblies are known in a prior art, there still exit a need to provide an arm support assembly that can better position a patient's arm during a surgical process. There is a further need for an arm positioning apparatus that can fully sterilized and that allows fully adjustable support of a patient's arm in a manner that facilitates better positioning and support of the shoulder arm and elbow joint while allowing unimpeded access thereto.


An apparatus for transplanting seedling from a first ray to a second tray. The apparatus includes a frame, a moveable gantry connected to the frame, and a conveyor system. In the preferred embodiment, a first conveyor is used to shuttle seedlings into the operative reaches of the apparatus and a second conveyor shuttles the transplanted seedlings out of the operative reaches of the apparatus. The gantry includes a gripper assembly comprised of a plurality of grippers slidably mounted to a track. A positioning mechanism is employed to move the gantry and associated gripper assembly. The grippers includes an upright support and a pair of pivotally connected spaced apart gripper fingers. The gripper fingers are separated by a plunger mechanism preferably having a beveled surface for ease of insertion between the gripper fingers.

1. Field of the Invention
The present invention relates generally to machines used in the nursery industry for taking seedlings extracted from a first seedling tray or "plug tray" and transplanting them into yet another second growing tray generally having a greater area of separation between the newly transplanted seedlings than the first plug tray from which they were extracted in order to encourage continued unimpeded growth of each individual seedling.
2. Description of the Related Art
In the nursery industry, plants are initially germinated and grown in trays having an array of small compartments within the tray. These small compartments are sufficient to accommodate the plant in the early stages of its development from a single seed into a small seedling while economically making use of the limited space available within a greenhouse or other nursery building. Once the seedlings have germinated and have approached the maximum size desirable while remaining in the small germination compartments, each seedling must be transplanted to a larger tray or pot for further growth and eventual outdoor planting or commercial sale.
The roots of the seedlings will typically form a compact ball with the soil contained within the tray compartments, which allows the seedling and the associated soil to be transplanted as a unit (the seedling "plug"). In the past, seedlings have been transplanted by hand into pots or other trays with larger compartments that have been pre-filled with soil. Hand transplanting allows seedlings to be easily transplanted from seedling arrays of any configuration to single pots or, more commonly, arrays of pots contained within a unitizing flat. However, the high cost of labor and the seasonal nature of such transplanting work has made this method undesirable.
Automatic transplanters are known which utilize specially fabricated seedling flats which permit the seedlings to be pressed through the base of a germination compartment into a pot located below. Other known transplanters use cam-driven rotating pairs of plate-like fingers to extract the seedlings, or utilize pre-bent metallic wire fingers which are retained in a straight configuration and injected into the soil surrounding the seedling. These known devices move the germinating tray on an indexable table with respect to the transplanting head of the apparatus.
What is needed is an apparatus of sturdy construction which may readily accommodate germinating trays of varying compartmental array dimensions, and which will rapidly transplant seedlings to larger trays of other compartmental array configurations. The present invention relates to apparatuses and methods of transplanting young plants from seedling trays to larger trays.
In the art to which the invention relates, complicated systems have been developed to transplant plants from a seedling plug tray, where they have initially germinated, to a larger flat tray where they will have more room to grow. These systems have been unduly complicated, and have sometimes injured the seedlings. In the case of a begonia seedling for example, begonia leaves are broad and grow close to the surface of the soil from which the primary stem extends. The prior systems and machines have been known to damage these types of plants (e.g., begonias) when the seedling is extracted from the tray in which it germinates originally.
It would be desirable to develop a plant transplant apparatus and method which can quickly and accurately transplant plants from a seedling tray to a larger tray. Further, it would be desirable to develop such an apparatus and method which can transplant the plants without damaging the seedlings, and have it adaptable to various sizes and types of trays and plants.

Seedling transplanter with planting fingers


A system for confirming authorization of a operator for controlling a vehicle on fixed paths, the system having at least one ride vehicle with an onboard control system being configured to confirm operator authorization prior to allowing operator control thereof and an electronic device dimensioned and configured to be supported by an operator, the electronic device being further configured to remotely authorize operator control of the onboard control system. A method for confirming authorization of an operator for controlling a vehicle on fixed paths is also provided.

The present invention relates to vehicles that reside on a fixed path. More specifically, the present invention relates to a control system and method for vehicles that reside on a fixed path.
Since the early twentieth century, controlling vehicles that reside on a fixed path such as trains, intrafactory cargo vehicles, and amusement park rides has lead to important industrial growth and consumer satisfaction. In the case of amusement parks, guests have demanded bigger, better, and more elaborate rides, they also require and expect a positive park experience, which entails progressively shorter waits to enter a ride. This requires Park management to balance two very important interests—guest satisfaction and safety.
Integrated control systems for a number of rides, from rollercoasters to log flumes, is known. In the past, human operators along the ride path would control breaking mechanisms to maintain vehicle spacing. More recently, path-mounted sensors have been used to control breaking and vehicle spacing. Other attractions use a plurality of platen drives, having a wheel or other path-mounted drive element that contacts a platen of each ride vehicle, to drive and control speed of the ride vehicles at all locations along the path. These control systems are generally limited to controlling ride vehicles at the operator control console, typically located at the boarding station. From the operator control console, the operators also have the ability to control not only breaking, but dispatch, reentry and tuning as well.
Recently, an onboard control system was disclosed by Baxter, et al., EP 0 667 798 B1. Baxter discloses an onboard control system that controls actions of the particular vehicle in the form of one of steering, velocity and articulation of a motion base relative to a passenger supporting structure, according to a programmably defined motion pattern defined by sequenced program instructions of a ride program, the motion pattern providing a defined spatial interaction with a dimensional set element.
The above types of control systems are insufficient because in many cases, two operators are required for dispatching a car. For example, in the case of rollercoasters, one operator must support the operator control console while another operator checks the safety feature of the car such as shoulder bars and seat belts. This, in effect, doubles the cost of labor for each ride.
Accordingly, to date, no suitable system or method for controlling vehicles on a fixed path is available.

System and method for controlling a vehicle on fixed path


A child-resistant closure includes a plastic inner shell having a base wall with a peripheral skirt, at least one internal thread segment on the peripheral skirt and a plurality of internal lugs on the base wall adjacent to the skirt. A plastic outer shell has a base wall with a peripheral skirt and a plurality of internal L-shaped lugs at a juncture of the base wall and the peripheral skirt. Each of the L-shaped lugs includes a first portion extending radially inwardly along an undersurface of the base wall of the outer shell for engaging the external lugs on the inner shell, and a second portion extending axially along an inner surface of the peripheral skirt of the outer shell for slidably engaging the inner shell and aligning the inner shell within the outer shell. The second portions of the L-shaped lugs preferably have rounded radially inwardly facing surfaces for reduced sliding friction with the skirt of the inner shell.

U.S. Pat. No. 4,997,096 discloses a child-resistant closure having inner and outer plastic shells. The outer plastic shell has a base wall, a peripheral skirt and a circumferential array of lugs on an undersurface of the base wall. The inner plastic shell has a base wall, a peripheral skirt, at least one internal thread segment on the skirt, and a circumferential array of lugs on an outer surface of the base wall for opposed engagement by the internal lugs on the base wall of the outer shell. To remove the closure when it is threaded onto a container neck finish, the outer shell must be pushed axially against the inner shell and simultaneously rotated so that the lugs on the outer shell engage the lugs on the inner shell and rotate the inner shell with respect to the container neck finish. When the outer shell is rotated without applying an axial force to the outer shell, the lugs on the outer shell simply cam over the lugs on the inner shell and do not rotate the inner shell with respect to the container neck finish. Child-resistant closures of this type have been marketed for many years by applicants' assignee under the trademark ARGUS-LOC. See also GB 1529999. A general object of the present disclosure is to provide improvements in child-resistant closures of this type, and to provide packages that include such improved closures.
The present disclosure embodies a number of aspects that can be implemented separately from or in combination with each other.
A child-resistant closure in accordance with one aspect of the present disclosure includes a plastic inner shell having a base wall with a peripheral skirt, at least one internal thread segment on the peripheral skirt and a plurality of internal lugs on the base wall adjacent to the skirt. A plastic outer shell has a base wall with a peripheral skirt and a plurality of internal L-shaped lugs at a juncture of the base wall and the peripheral skirt. Each of the L-shaped lugs includes a first portion extending radially inwardly along an undersurface of the base wall of the outer shell for engaging the external lugs on the inner shell, and a second portion extending axially along an inner surface of the peripheral skirt of the outer shell for slidably engaging the inner shell and aligning the inner shell within the outer shell. The second portions of the L-shaped lugs preferably have rounded radially inwardly facing surfaces for reduced sliding friction with the skirt of the inner shell.
A child-resistant closure in accordance with another aspect of the present disclosure includes a plastic inner shell having a base wall, a peripheral skirt with at least one internal thread segment and an angularly spaced circumferential array of external lugs on the base wall. A plastic outer shell has a base wall, a peripheral skirt and an angularly spaced circumferential array of internal lugs on the base wall. The inner plastic shell is received within the outer plastic shell such that the internal lugs on the base wall of the outer plastic shell are disposed for engagement with the external lugs on the base wall of the inner plastic shell to apply or remove the closure to or from a container neck finish. The internal lugs on the outer shell and the external lugs on the inner shell have opposed rounded axially facing surfaces such that the internal lugs on the outer shell cannot rest on the external lugs of the inner shell upon application of force to the outer shell.
A child-resistant closure in accordance with a further aspect of the present disclosure includes a plastic outer shell having a base wall with a peripheral skirt and a plurality of internal lugs on the base wall adjacent to the skirt, and a plastic inner shell disposed within the outer shell and having a base wall with a peripheral skirt, at least one internal thread segment on the peripheral skirt and a plurality of external lugs on the base wall adjacent to the skirt. The base wall of the outer shell has a peripheral portion of a first thickness on which the internal lugs are disposed and an imperforate central portion of a second thickness less than the first thickness. The base wall of the inner shell has a peripheral portion of a third thickness on which the external lugs are disposed and an imperforate central portion of a fourth thickness less than the first thickness. The thinner central portions of the inner and outer shell reduce the weight and cost of the closure.

Two-piece child-resistant closure and package


A variable conductance heat pipe includes an electronic component mounting plate serving as the evaporator of the heat pipe. The evaporator is connected to an air cooled condenser which condenses vapor flowing from the evaporator. The evaporator has a sump located at the lowest gravity point of the evaporator passage. By either vaporizing or pumping liquid from the sump and passing it back through the heat pipe a continuing wetted condition exists in the heat pipe which can accommodate heat dissipation transients by the electronic components. A control loop is closed through the heat pipe for controlling the penetration of an inert gas into the heat pipe condenser to maintain a constant temperature for the electronic components mounted thereto.

In many applications, temperature control of electronic components is critical. For example, as a resistor heats up, the resistance itself increases and this can seriously alter the operation of the circuit in which the resistor is connected. In sensitive applications, a simple mechanical heat sink is insufficient to maintain a constant temperature.
Frequently, heat pipes are employed for cooling the environment of electronic circuits. However, they normally operate with a range of temperature variations which may be unacceptable for sensitive applications. More complicated refrigeration techniques, having feedback temperature control, may be employed. Unfortunately, they are quite expensive, require substantial power, and demonstrate limited reliability due to their complicated electromechanical nature.

Closed loop feedback control variable conductance heat pipe


The present invention provides a sripline-type transmission line which can easily change and control transmission characteristics by changing the permittivity of a substrate, and also provides an antenna that can extensively change and control the direction of radiation with the frequency of an electromagnetic wave constant, by using this transmission line.

It is possible to artificially constitute a medium that has properties not found in nature by arranging small pieces (unit cells) of a metal, a dielectric, magnetic material and a superconductor at sufficiently shorter intervals than a wavelength (about 1/10 of the wavelength or less). A medium like this is called a metamaterial, in the sense that it is a medium that belongs to a category that is larger than the category of a medium found in the natural world. The properties of a metamaterial change in various ways depending on the shape and material properties of the unit cell, and the arrangement thereof.
Among these, a metamaterial that has an equivalent permittivity ∈ and magnetic permeability μ and is simultaneously negative has been called a "left-handed medium (LHM: Left-Handed Materials)" because its electric field, magnetic field and wave vector form a left-handed system. In contrast to this, a normal medium that has an equivalent permittivity ∈ and magnetic permeability μ and is simultaneously positive is called a "right-handed medium (RHM: Right-Handed Materials)". The relationship between the permittivity ∈ and magnetic permeability μ and the type of medium is shown in FIG. 1. Mediums can be classified into a first quadrant to a fourth quadrant in accordance with a positive and negative permittivity ∈ and a positive and negative magnetic permeability μ. A right-handed medium is a first quadrant medium, and a left-handed medium is a third quadrant medium.
In particular, the left-handed medium has peculiar properties, such as the existence of a wave (called a backward-wave) having a wave group velocity (propagation velocity of energy) and a phase velocity (progression velocity of phase) with opposite signs, and an amplification of an evanescent wave, which exponentially decays in a nonpropagation region. Now then, it is possible to use a left-handed medium to artificially constitute a transmission line that transmits a backward-wave. This fact is disclosed in Non-Patent Document 1 and Non-Patent Document 2 cited hereinbelow.
Based on this concept of a left-handed medium constitution, a transmission line that propagates a backward-wave by periodically lining up unit cells comprising a metal pattern, is proposed. This transmission characteristic has been handled theoretically until now, and it has become theoretically evident that this transmission line has a left-handed transmission band, that a bandgap occurs between the left-handed transmission band and the right-handed transmission band, and that the bandgap width thereof can be controlled by the reactance among the unit cells. Further, a transmission line that is capable of simultaneously transmitting a left-handed transmission band and a right-handed transmission band is called a composite right/left-handed transmission line. These points are disclosed in Non-Patent Document 3 cited hereinbelow.
FIG. 2 is a diagram showing the constitution of a microstrip line commonly used in the past. FIG. 2(A) is an oblique view of the microstrip line, and FIG. 2(B) is a cross-sectional view showing an overview of the electromagnetic field of an electromagnetic wave propagated over the microstrip line. The microstrip line comprises a conductor 4 that serves as a transmission line disposed on the front surface of a substrate 1 of thickness d comprising a dielectric substance, and a ground conductor 3 disposed on the rear surface of the substrate 1. The electric field E and magnetic field H of the electromagnetic wave propagated over this microstrip line are as shown in FIG. 2(B). Since a half-space is opened on the one side of the transmission line (the top surface side) of the microstrip line, radiation toward the space occurs in the radiation region (region in which the phase constant of the propagation wave of the transmission line is smaller than the in-vacuum wave number).
A right/left-handed transmission line based on the constitution of the transmission line of this type of microstrip line has already been produced, and the transmission characteristics of this microstrip line-type right/left-handed transmission line have been verified experimentally. This is disclosed in Non-Patent Documents 2 and 3. The microstrip line-type right/left-handed transmission line is such that unit cells comprising conductors that are insulated from one another are periodically arrayed in the z direction as conductors 4 in FIG. 2(A).
Because the microstrip line-type right/left-handed transmission line has a property that radiates a portion of the transmission energy in a frequency region in which the phase constant of a wave is smaller than the in-vacuum wave number, it is confirmed that the right/left-handed transmission line can be used as an antenna by taking advantage of this property. This is disclosed in Non-Patent Documents 2 and 3.
In addition to the microstrip line, a stripline has also been used as a transmission line for some time now. FIG. 3 is a diagram showing the constitution of a stripline. FIG. 3(A) is an oblique view of the stripline, and FIG. 3(B) is a cross-sectional view showing an overview of the electromagnetic field of an electromagnetic wave propagated over the stripline. The stripline is such that ground conductors 2 and 3 are disposed on the front surface and rear surface of a substrate 1 of thickness s comprising a dielectric substance, and a conductor 4 is disposed as a transmission line in an intermediate plane of the substrate 1 (plane located at a thickness of s/2). The electrical field E and magnetic field H of the electromagnetic wave propagated over this stripline are as shown in FIG. 3(B). Radiation essentially does not occur because both the front surface and rear surface of the stripline are covered by ground conductors 2, 3.
The inventors have already proposed a composite right/left-handed transmission line and left-handed transmission line based on this stripline-type transmission line constitution. This is the transmission line shown in FIGS. 4(A) and (B). FIG. 4(A) is an oblique view displaying only the conductor that constitutes the transmission line, and FIG. 4(B) is a cross-sectional view of the transmission line. This transmission line is such that ground conductors 2 and 3 are disposed on the front surface and rear surface of a substrate 1 of thickness s comprising a dielectric substance, and a conductor pattern 4 is disposed as a transmission line in an intermediate plane of the substrate 1 (plane located at a thickness of s/2). The conductor pattern 4 is such that unit cells comprising conductors that are insulated from one another are arrayed periodically in the direction of transmission.
[Non-Patent Document 1] D. R. Smith, W. J. Padilla, D. C. Vier, S. C. Nemat-Nasser, and S. Schultz, "Composite medium with simultaneously negative permeability and permittivity", Phys. Rev. Lett., vol. 84, no. 18, pp. 4184-4187, May 2000
[Non-Patent Document 2] C. Caloz and T. Itoh, "Application of the transmission line theory of left-handed (LH) materials to the realization of a microstrip LH line", IEEE-APS Int'l Symp. Digest, vol. 2, pp. 412-415, June 2002
[Non-Patent Document 3] Atsushi Sanada, Christophe Caloz and Tatsuo Itoh, "Characteristics of the Composite Right/Left-Handed Transmission Lines", IEEE Microwave and Wireless Component Letters, Vol. 14, No. 2, pp. 68-70, February 2004
When a conventional microstrip line-type right/left handed transmission line is used as a leaky-wave antenna, the direction of a radiating electromagnetic wave can be changed by changing the frequency of the electromagnetic wave to be propagated. However, when the frequency variability range is small, the change in the direction of the radiating electromagnetic wave cannot be controlled across a broad range. Further, it is the same when a constitution for radiating an electromagnetic wave is added to a stripline-type right/left-handed transmission line, and this stripline-type right/left-handed transmission line is used as a leaky-wave antenna, and the change in the direction of the radiating electromagnetic wave cannot be controlled across a broad range when the frequency variability range is small.

Stripline-type composite right/left-handed transmission line or left-handed transmission line, and antenna that uses same


An outer ring has a spherically convex outer surface mounted within a bore of a housing such that the outer ring may be misaligned with respect to the axis of the bore. A sensor target is mounted on an inner ring that is rotatable with respect to the outer ring, and a seal is mounted on the outer ring. A sensor is mounted on the seal in proximity to the sensor target, and a flexible electrical conductor is connected to the sensor for transmitting signals from the sensor. A portion of the flexible electrical conductor is fixed with respect to the housing. Circuitry may be electrically connected to the flexible electrical conductor. The flexible conductor and circuitry may be provided by a flexible circuit board.

This invention relates generally to a self-aligning bearing mounted within a housing and, more particularly, to a housed, self-aligning bearing with an integral sensor for detecting speed or position of a rotating shaft.
Various bearings are available commercially with integral sensors for the purpose of measuring bearing or system parameters such as speed or position of a shaft rotating within the bearing. However, a problem experienced with those designs is lack of protection for the sensor components with respect to vibration, chemical or water contamination, dust or debris, impact, etc. This is especially true when the sensors and related electrical circuitry are miniaturized and are not robust.
Although such bearings with integral sensors work well in many applications, they may be unsuitable in the harsh working environments of applications requiring a rugged, self-aligning bearing. In those applications, the sensor, circuitry components or wiring could be damaged. Those sensor components may also be damaged in less severe applications if the self-aligning bearing is subjected to rough handling, either prior to or during a difficult installation, for example.
The foregoing illustrates limitations known to exist in present devices and methods. Thus, it is apparent that it would be advantageous to provide a more robust housed self-aligning bearing with integral sensor to overcome one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.


A safety closure for use on a container neck having a closure top wall, an annular sidewall depending downwardly from an outer periphery of the top wall defining an open bottom opposite the top wall. The sidewall has inner annular surface with a plurality of lugs projecting inward therefrom, wherein each lug has a lug top surface forming an angle of incidence of greater than 90° with the inner annular surface of the annular sidewall. The plurality of lugs are engageable with a plurality of lug receiving notches in a plurality of bayonet lugs on a container neck. A spring member depends from the closure top wall and is resiliently engageable with the container neck to bias the safety closure away from the container neck. Optional closure retaining means may be incorporated within the closure, container, or both.

The use of cooperating locking lugs on safety closures and containers to prevent children from gaining access to the contents of the container is well known in the prior art. Drugs, corrosive products, and antifreeze are examples of substances that are commonly packaged in containers or bottles having child-resistant or safety closures. The closures and their complementary containers are designed to allow the user to open the container without allowing a child to open the same.
An example of a child resistant closure and container is a push-and-turn system which is typically used for pill containers. This system requires that the closure or cap for the pill container be pushed axially downwardly and rotated at the same time. These containers are typical a two-piece, ramp and lug design. Essentially, the closure comprises an inner cap and an outer cap which are rotatably attached to one another. A plurality of lugs on one cap project towards a plurality of corresponding ramps on the opposite cap. Generally, the ramps and lugs engage each other when turned in a fastening direction such that the two caps turn in tandem. However, when the cap is merely rotated in an "unfastening" direction, the lugs tend to slide over the ramps. The outer cap turns freely from the inner cap, and the inner cap remains fastened to the container. In order to open the cap, the outer cap must be pushed downward in order to counteract the tendency of the lugs to slide over the ramps while the cap is being turned.
Another safety closure found in the prior art has bayonet type closures in which one of the closure and the container has a set of bayonet lugs and the other has a set of mating lugs so that it is necessary to urge the closure toward the container while applying a rotative force in order to disengage the bayonet lugs from the mating lugs to remove the closure from the container.
A typical configuration of the bayonet type closures found in the prior art are such that they have lugs or other features in the cap or closure that have a lug top surface forming an angle near 90° with an inner annular surface of the closure. This lug top surface cooperates with a bayonet lug having a lug receiving notch where the lug receiving notch has a top surface forming an angle near 90° with an outer surface of the container neck. This "square" cooperation retains the closure on the container by countering an axial force on the closure.
This "square" configuration found in the prior art creates costly and inefficient manufacturing problems. In the injection molding process the closure is axially removed from a mold core. In order to accomplish this removal, a collapsible mold core is typically used or alternatively holes are placed in the top wall of the closure to remove a portion of the mold which forms the lug top wall. This provides channels in the mold core for the closure lugs thus enabling axial removal of the closure from the mold core.

Bayonet closure container combination with angled bayonet lugs


A plurality of land sections, each enclosed by two slits, are formed in a ground wire provided on a side of a flexible wiring board to which a piezoelectric element is connected. Since the ground wire and the land sections are connected by only a thin connection section, the solder deposited on the land sections does not flow to the ground wire.

The present invention relates to an inkjet head that ejects an ink from a plurality of ejection outlets by pressure generated by a piezoelectric element when a drive element drives the piezoelectric element through a wiring board.
In an inkjet printer, color printing is performed using a plurality of ink cartridges, such as cyan, magenta, yellow and black cartridges, and inks supplied from a plurality of ink cartridges are ejected from a plurality of ejection outlets formed in the inkjet head by pressure generated by a piezoelectric element. The piezoelectric element generates pressure according to a drive voltage supplied from a driving IC, and the drive voltage from the driving IC is supplied to the piezoelectric element through a flexible wiring board.
The flexible wiring board is constructed by providing a plurality of wires on one or both surfaces of an insulating film. Using the flexible wiring board for the transmission of a drive voltage, a control signal, etc. is advantageous because it is possible to increase the degree of freedom in mounting an inkjet head in an inkjet printer and decrease the size of the inkjet printer. In recent years, a COF (Chip On Film) comprising a driving IC mounted directly on a flexible wiring board has been put into practical use. Since the COF can shorten the distance from the driving IC to the piezoelectric element, it is possible to reduce the attenuation and delay of the drive voltage, and it is possible to efficiently drive the piezoelectric element.
In a connection structure of a flexible wiring board disclosed in Japanese Patent Application Laid-Open No. 2004-114609, a plurality of terminal lands and wires are formed on one surface of a band-shaped insulating body, through-holes for exposing the terminal lands from the other side are formed in the insulating body, and the terminal section of the piezoelectric element of the inkjet head and the terminal land are connected by solder through the through-hole. In other words, the solder is deposited only on the terminal lands exposed at the other side of the insulating body. Thus, since the terminal lands and the wires on one surface are isolated from the solder by the insulating body, a short circuit of wires due to leakage of solder will never occur.

Inkjet head and connection structure of wiring board


A multi-purpose, front-loading display frame includes a front frame member having a window section for viewing a display item disposed therebehind and a rear frame member for releasably supporting at least one interchangeable display item. The front frame member is hingedly secured to the rear frame member so as to allow for pivotable movement of the frame members between a closed position, in which the frame members are disposed closely adjacent to one another so that a display item supported on the rear frame member is disposed behind the window section for viewing, and an open position, in which the frame members are pivoted apart from one another to permit removal and replacement of the display item. A closure member is mounted on at least one of the front and rear frame members for releasably maintaining the front and rear frame members in the closed position thereof. The closure member is positioned to allow the front frame member to be swung open while the rear frame member is still mounted on a support.

1. Field of the Invention
The present invention relates to a multi-purpose display frame. More particularly, it relates to a swing-open, front loading wall display frame for displaying printed memorabilia, such as magazines, comic books, paintings, photographs, documents, diplomas and other graphic art items and collectibles.
2. The Prior Art
Various picture, poster and other multi-purpose frames are available for displaying a wide variety of printed graphic art material. (See, for example U.S. Pat. No. 4,822,195, to Lu; U.S. Pat. No. 5,018,291, to Pasquale et al; and U.S. Pat. No. 4,984,798, to Silberstein.) In particular, U.S. Pat. No. 4,446,206, to Meadows, discloses a picture frame which includes a substantially flat transparent window surrounded by a frame member which, in turn, is hingeably secured to a substantially flat closure back panel holding the intended graphic against the transparent window when the closure back panel is in a closed position. A combination latch and hanger member is provided for hanging the frame and maintaining the front and back panels in a closed position, and the device preferably includes a plurality of compression pads which press against the graphic when the closure back panel is in the closed position. However, to change the picture, one most remove the frame from the wall to enable one to open the latch, swing open the back flap, and remove and replace the old picture. This procedure occurs every time the art work needs to be inserted, removed or replaced. In addition, the top portion of the latch protrudes above the frame which is aesthetically unacceptable.
U.S. Pat. No. 4,958,458, to Hillstrom et al, discloses a poster display frame fastened via conventional means to a rigid supporting member such as posts, walls or the like. The sides of the Hillstrom frame comprise sets of both front and back frame members which are interconnected and pivotably engaged and made from extruded metal or molded plastic. A spring member is necessary to bias the front and back frame members into mating pivotal engagement and bias the front frame members against the poster and backing frame member when the frame sections are closed, as well to hold the front frame members in their open positions. This frame requires complicated fabrication/molding of the frame members and hinge assembly. The Hillstrom frame requires a rather complicated cylindrical hinge o pivot pintle formation on the back of the back frame member and a corresponding cup-shaped socket portion formed on the back panel of the front frame member. The two are joined either slidably or snapped together. The Hillstrom device also cannot use conventional industry standard metal picture frame extrusions.
U.S. Pat. No. 4,947,565, to Shadwell, discloses a picture framing assembly which includes a rectangular picture frame that can be opened and closed repeatedly for mounting and changing the picture to be displayed in the frame. The picture framing device is characterized by a rigid backing sheet which is hinge mounted along one edge of the frame and releasably secured to the frame along the other three edges with adhesive tape. The device has a backing sheet having an adhesive strip on the surface of the mat facing the backing sheet for releasably securing the picture to be displayed to the mat. Here, too, like Meadows, the picture frame must be removed from the wall to allow for the opening and closing of the backing sheet. In addition, the backing sheet is hinged by tape which is also taped around the other edges of the frame. Slight finger pressure must be used in an opening in the corner of the backing sheet to release the backing sheet and provide access to the recessed cross-section of the frame to enable one to insert, remove, or replace the picture to be displayed. The picture frame is re-sealed by re-securing the tape all around the back of the frame. This does not permit ready access and is time consuming.
U.S. Pat. No. 4,756,108, to Lackay et al, discloses a display frame for displaying posters, advertisements and other printed matter which has a rectangular front frame which supports a transparent window which, in turn, is hingeably mounted at its bottom to a vertical solid face via vertical support modules. The vertical solid face includes a compressible backing for holding display material in place behind the window which must be removed when replacing the picture. The device also requires a rather complicated hinge and clamping device.
In summary, each of the above frames have substantial disadvantages. Some are rather complicated in construction, and others are difficult to use to effect replacement of the display item. Furthermore, others do not afford sufficient protection and ease of use for framing collectibles in a non-damaging manner, which is important for maintaining the value of the printed graphic such as comic books cartoon cells, baseball cards and the like.


An adjustable chair headrest frame includes a headrest provided with a pivotal frame at the rear side. A support frame is pivotally assembled with the pivotal frame of the headrest, having its inner side formed with a recessed face having its outer periphery fixed with plural female-thread studs. An adjusting device is combined at the inside of the support frame, composed of a fit plate, plural stop blocks, a holding plate, springs and a back plate. A combining plate is threadably combined with the fit plate of the adjusting device and assembled at the rear side of a chair. By so designing, the headrest frame can be adjusted upward or downward, and the headrest can be adjusted and positioned at different angles.

1. Field of the Invention
This invention relates to an adjustable chair headrest frame, particularly to one assembled on a chair for a user's head to rest thereon, able to be adjusted upward or downward for matching with a user's height and enabling a headrest to be adjusted at different angles.
2. Description of the Prior Art
A chair with a headrest enables a user to rest on the chair and lean his head on the headrest for relaxing tense muscles of the shoulders and the neck after the user has done office work for a long time. However, a conventional chair headrest is generally fixed immovably on a chair and hence cannot be adjusted upward or downward for tallying with different heights of users, nor can it be adjusted in angles for effectively supporting a user's head on the headrest.


Provided are apparatus and methods for forming a multidimensional image of inanimate or animate objects which utilize a magnetization source (112) to magnetize a volume of an object to be imaged, a radiation source (118) for applying a radiation field to the object to be imaged, an output signal detector (120) for producing output signals in response to the secondary radiation at a plurality of spatial locations outside of the object as a function of time, processors (126, 126a and 126b) for determining a plurality of Fourier components, for associating the Fourier components due to each voxel (14) by phase, and for converting each set of components into a voxel location, and an image processor (128) for producing an image.

Nuclear Magnetic Imaging (NAMR) which is commonly called magnetic resonance imaging(MRI) entails 1.) magnetizing a volume with a constant primary magnetic field in a z-direction, 2.) providing a gradient along the axis of the z-directed field to select a slice in the xy-plane, the plane perpendicular to the direction of the primary field, 3.) providing electromagnetic radiation resonant with the Larmor frequency of protons in the slice, 4.) providing a pulse of resonant electromagnetic radiation to flip the magnetization vector into the transverse plane or plane of the slice, and 5.) applying a magnetic field gradient along an axis in the xy-plane of the z-directed field with excitation at the Larmor frequency to provide phase dispersion of the NMR signal along the axis to encode spatial information, and 6.) recording the free induction decay (FID) radio emission signals following excitation, 7.) recording a plurality of such FIDs, each recorded following an excitation with a rotated direction of the gradient in the xy-plane, and 8.) reconstructing the image from the plurality of the FIDs. An integer n of FIDs each having a phase gradient that corresponds to the magnetic field gradient that was rotated to n unique directions in the xy-plane comprise a set along two orthogonal axes in phase or k-space. A two dimensional Fourier transform of the data set is used to reconstruct an n by n pixel image.
MRI is of primary utility in assessing brain anatomy and pathology. But long NMR relaxation times, a parameter based on how rapidly excited nuclei relax, have prevented NMR from being of utility as a high resolution body imager. The most severe limitation of NMR technology is that for spin echo imaging n, the number of free induction decays ("FIDs"), a nuclear radio frequency energy emitting process, must equal the number of lines in the image. A single FID occurs over approximately 0.1 seconds. Not considering the spin/lattice relaxation time, the time for the nuclei to reestablish equilibrium following an RF pulse, which may be seconds, requires an irreducible imaging time of n times 0.1 seconds, which for 512×512 resolution requires approximately one minute per each two dimensional slice. This represents a multiple of 1500 times longer that the time that would freeze organ movements and avoid image deterioration by motion artifact. For example, to avoid deterioration of cardiac images, the imaging time must not exceed 30 msec. A method for speeding NMR imaging flips the magnetization vector of the nuclei by less than 90 degrees onto the xy-plane, and records less FIDs. Such a method, known as the flash method, can obtain a 128×128 resolution in approximately 40 seconds. Another technique used to decrease imaging time is to use a field gradient and dynamic phase dispersion, corresponding to rotation of the field gradient, during a single FID to produce imaging times typically of 50 msec. Both methods produce a decreased signal-to-noise ratio ("SNR") relative to spin echo methods. The magnitude of the magnetization vector which links the coil is less for the flash case because the vector is flipped only a few degrees into the xy-plane. The echo-planar technique requires shorter recording times with a concomitant increase in bandwidth and noise. Both methods compensate for decreased SNR by increasing the voxel size with a concomitant decrease in image quality. Physical limitations of these techniques render obtaining high resolution, high contrast vascular images impractical.

4 dimensional magnetic resonance imaging


An outboard motor having a steering control and a rudder reference sensor, both connectible to a computer-operated guidance system. The steering control utilizes a linear actuator connected through a linkage to the motor. The actuator utilizes a rack that moves along the axis about which the motor pivots from its use position to its storage position, thereby enabling the rudder position sensor to remain connected to the motor when the motor is pivoted from its use position to its storage position. The sensor can include a follower disposed in a sloping groove on the rack, a pin on the rack engaged in a helical groove on a cylinder, or an externally mounted sensor connected to the steering linkage through an auxiliary linkage.

Steering assemblies are known that can be used to steer inboard/outboard or outboard motors attached to the stern of a boat and used to propel the boat, which steering assemblies include a rudder reference sensor including a variable resistance potentiometer that can provide a different electrical signal for each position to which the rudder and propeller of the outboard motor or outboard portion of the inboard/outboard can be rotated with respect to the stern of the boat. That signal from the rudder reference sensor is sent to a known type of computer-operated guidance system on the boat that can attempt to keep the boat traveling along a desired directional heading by determining the actual heading of the boat and, if that actual heading is not the same as the desired heading, can determine an appropriate direction and amount to rotate the rudder and propeller of the outboard motor or outboard portion of the inboard/outboard in an attempt to correct the heading of the boat . Then, based on that determination, the guidance system can operate the steering mechanism to position the rudder and propeller of the outboard motor or outboard portion of the inboard/outboard motor so that it will change the heading of the boat toward or to the desired heading.
Known rudder reference sensors, (e.g., the Raymarine E15022 "Rotary Rudder Reference Bracket", model 5915368, or the Raymarine M81188 Linear Rudder Reference sensor for outboards, model 251251, both of which are commercially available from West Marine, Watsonville, Calif.) while suitable for use with inboard/outboard type drive systems, are not easily adaptable for use with small horsepower outboard motors (e.g., 5 to 10 h. p.) used to propel fishing boats at slow speeds (e.g., 1 to 3 m.p.h.) while trolling for fish. A major portion of such an outboard trolling motor including its rudder and propeller is typically pivoted over about 40 degrees between a use position with the rudder and propeller of the outboard motor under the water where it can propel the boat during trolling, and a storage position with all of the outboard motor including its rudder and propeller above the water surface where they will not interfere with operation of the boat at high speed by a main drive system on the boat. The known way in which commercially available rudder reference sensors are used to indicate the position of such outboard motors is to connect the rudder reference sensor to the outboard motor only when the outboard motor is in its use position, and then disconnect the rudder reference sensor from the outboard motor before the outboard motor is pivoted to its storage position with its rudder and propeller above the water's surface. This can be very inconvenient, particularly when structure at the stern of the boat (e.g., a row of fishing rods in sockets) limits access to the outboard motor.

Outboard motor steering assembly with rudder reference sensor


Several lines of transgenic mice have been generated using the prostate-specific rat probasin (PB) gene promoter to drive expression of the SV40 T antigen (Tag) coding region. Mice expressing high levels of the transgene specifically display progressive forms of prostatic cancer that histologically resemble human prostate cancer ranging from mild prostatic intraepithelial neoplasia (PIN) to large multinodular malignant adenocarcinoma with metastasis. Adenocarcinomas of the prostate have been detected as early as 10 weeks of age with extracapsular extension (ECE) and seminal vesicle invasion (SVI). Immunohistochemical analysis of tumor tissue has demonstrated that dorsolateral prostate-specific secretory proteins were confined to well differentiated ductal epithelial cells adjacent to, or within the poorly differentiated tumor mass. Prostate tumors in the mice also display elevated levels of nuclear p53, and a decreased heterogenous pattern of androgen receptor (AR) expression as observed in advanced human prostate cancer. The establishment of breeding lines of transgenic mice that reproducibly develop prostate cancer with metastasis provides a unique animal model system to study the molecular basis of transformation of normal prostatic cells and the factors influencing the progression to metastatic prostate cancer.

Prostate Cancer PA0 Probasin Gene PA0 SV40 T Antigen PA0 Transgenic Animal Models
Prostate cancer will likely claim the lives of 35,000 men in the United States this year alone and some 200,000 more men will be diagnosed with the disease (Silverger, Boring & Squires, 1990). However, progress toward understanding the biology of prostate cancer and the development of new therapies for this disease has been slowed, in part, by the need for new in vivo model systems that adequately reproduce the spectrum of benign, latent, aggressive and metastatic forms of the human disease.
Prostate cancer is a disease quite unique to man. Although naturally occurring prostatic disease has been reported in some canine (Berry, Coffey, & Ewing, 1984) and rodent (Noble, 1977; Pollard, 1973; Pollard & Luckert, 1987; Shain, McCullough, Nitchuk, & Boesel, 1977; Shain, McCullough, & Segaloff, 1975) species, these animals have not provided the appropriate models to adequately study the molecular mechanisms related to the early development and progression of human prostate cancer. To this end, we initiated a research program to establish a transgenic animal model for prostate cancer using a prostate-specific transgene expression system that has been developed based on the regulatory elements of the rat probasin (rPB) gene.
The rPB gene encodes an androgen- and zinc-regulated protein specific to the dorsolateral epithelium (Dodd, Sheppard & Matusik, 1983; Matusik, Kreis, McNicol, Sweetland, Mullin, Fleming, et al., 1986; Sweetland, Sheppard, Dodd & Matusik, 1988). Isolation of the rPB gene has facilitated identification of cis-acting androgen response regions within the 5' flanking region (Rennie, Bruchovsky, Leco, Sheppard, McQueen, cheng, et al., 1993). More recently, the ability of the prostate specific rPB gene promoter to target heterologous genes specifically to the prostate in transgenic mice has been demonstrated (Greenber, DeMayo, Sheppard, Barrios, Lebovitz, Finegold, et al., 1994). In these studies, an expression cassette carrying 426 base pairs (bp) of the rPB gene promoter and 28 bp of 5' untranslated region (5'UT) was found to be sufficient to target expression of a bacterial chloramphenicol acetyl transferase (CAT) reporter gene specifically to the prostatic epithelium. These studies demonstrated that the minimal rat probasin promoter was specifically regulated by androgens in vivo with the ability to target developmentally- and hormonally- regulated expression of a heterologous gene specifically to the prostate in transgenic mice.
The latter studies, showing prostate-specific targeting of heterologous gene expression products is described in the aforementioned U.S. Ser. No. 08/351,365 and published in the corresponding WO 94/03594, the disclosures of which are incorporated herein by reference.
The SV40 early region-tumor antigens (Tag) have the ability to induce transformation in vivo (Brinstar, Chen, Messing, Van Dyke, Levine, & Palmiter, 1984). The SV40 large T antigen acts as an oncoprotein through interactions with the retinoblastoma(Rb) (DeCaprio, Ludlow, Figge, Shew, Huang, Lee, et al., 1988) and p53 (Lane & Crawford, 1979; Linzer & Levine, 1979) tumor suppressor gene products. The small t antigen interacts with a protein phosphatase (Pallas, Shahrik, Martin, Jaspers, Miller, Brautigan, et al., 1990) presumably to regulate activity of the mitogen activated protein kinase activation pathway and the AP-1transcription factor activity (Frost, Alberts, Sontag, Guan, Mumby, & Feramisco, 1994). The SV40 early region tumor antigens have been used successfully in transgenic mice to induce a transformed state in a variety of systems from pancreas (Hanahan, 1985), mammary gland (Tzeng, Guhl, Graessmann, & Graessmann, 1993), to the ductal epithelium of lung and kidney (Choi, Lee & Ross, 1988) and others (see (Adams & Cory, 1991) for review). Since the loss of wild-type p53 and Rb have been implicated in development and progression of prostate cancer (Bookstein, Rio, Madreperla, Hong, Allred, Grizzle, et al., 1990; Cooke, Quarmby, Mickey, Isaacs, & French, 1988; Isaacs, Carter, & Ewing, 1991; Rubin, Hallahan, Ashman, Brachman, Beckett, Virudachalam, et al., 1991), we hypothesized that directly expressing SV40 tumor antigens in the prostate epithelium of transgenic mice might provide a new mouse model for the development and progression of prostate cancer.
Previous efforts to establish experimental animal models of prostate cancer have explored other primate systems (Habenicht, el-Etreby, Lewis, Ghoniem, & Roberts, 1989), or have focussed primarily on the effects of sex hormones that displays a very low frequency of spontaneous prostatic disease. For example, rats treated with sex hormones (Noble, 1977) developed adenocarcinoma of the prostate, as did rats treated with methylnitrosourea (Pollard & Luckert, 1987), testosterone and cyproterone (Pollard, Luckert & Snyder, 1989) or methylnitrosourea, dimethylbenzanthracene, or dimethylaminobiphenyl after sequential treatment with cyproterone acetate and testosterone propionate (Bosland & Prinsen, 1990; Bosland, Prinsen, Dirksen, & Spit, 1990). In addition, prostate tumors arise following cadmium (Waalkes, Rehm, Riggs, Bare, Devor, Poirer, et al., 1988) administration to WistarCrl:(WI)BR! rats and estradiol and dimethylaminobiphenyl (Shirai, Fukushima, Ikawa, & Ito, 1986) administration to F344 rats. Unfortunately, these protocols induce highly variable primary tumors and are not amenable to studying the molecular events involved in the progression of latent locally defined disease to adenocarcinoma and metastasis. Similarly, efforts to develop in vitro models for prostate cancer have produced the Dunning (Bogden, Taylor, Moreau, & Coy, 1990) (Cooke, et al., 1988), PC-3 (Rubin, et al., 1991) and PC-82 (van & Schroder, 1988) cell lines that are capable of inducing xenograft tumors. More recently, new LnCaP sublines have been developed that are androgen-independent (Thalman, Anezinis, Chang, Zhau, Kim, Hopwood, et al., 1994). However, these systems do not facilitate characterization of the earliest events in the progression of prostate cancer and established tumor cell lines may have been selected either for a number of genetic alterations not found in the primary tumors or acquired mutations in vitro (Carroll, Voeller, Sugars, & Gelmann, 1993; Rubin, et al., 1991). To this end, in vivo gene transfer studies were pursued recently in an attempt to develop a new generation of prostate cancer research models.
Retrovirus mediated gene transfer has been used to develop a mouse prostate reconstitution model (MPR). In this system, the Ha-ras and c-myc genes are first introduced into the fetal urogenital sinus and a reconstituted organ is then transplanted under the renal capsule of host mice leading to the rapid development of adenocarcinoma (Thompson, Southgate, Kitchener, & Land, 1989). MPR has been used previously to demonstrate that co-operativity between Ha-ras and c-myc leads to the transformation of reconstituted prostates (Thompson, Kadmon, Timme, Merz, Egawa, Krebs, et al., 1991; Thompson, Timme, Kadmon, Park, Egawa, & Yoshida, 1993a; Thompson, Truong, Timme, Kadmon, McCune, Flanders, et al., 1993b; Thompson, et al., 1989), and that dietary fenretinide can reduce the incidence of these tumors (Slawin, Kadmon, Park, Scardino, Anzano, Sporn, et al., 1993). Furthermore, MPR studies have demonstrated that TGF.beta.1 may be a marker in the progression of prostate disease from benign to malignant status (Thompson, et al., 1993b), and more recently, that p53 inactivation is related to increase tumorigenesis, and metastasis (Timme, Park, Ren, Eastham, Baley, Kadmon, et al., 1994).
Previous attempts by other investigators to establish transgenic targeting systems based on the regulatory elements of cellular or viral genes known to be expressed in the prostate have met only with limited success.
Studies in vivo demonstrate that C3(1) is induced 2-to-4 fold transcriptional by androgens (Parker et al, 1988; Parker and Needham, 1985), causing the authors to suggest post-transcriptional regulation (page and Parker, 1982).
When a fragment of the rat C3(1) gene was fused to a heterologous .beta.-gal reporter gene, the spatial pattern of C3(1)-.beta.gal fusion transgene expression was not found to be uniform (Buttyan & Slawin, 1993). Mice carrying a C3(1)-Tag transgene have recently been generated (Maroulakou, Anver, Garrett, & Green, 1994). In the two lines of C3(1)-Tag mice that have been propagated, the males develop prostatic hyperplasia and adenocarcinoma while the female mice develop mammary carcinoma. In general, the majority of male mice were observed to develop prostate adenocarcinoma by 8 months of age. Interestingly, a number of phenotypic abnormalities were also observed in the founder mice with only two animals surviving longer than 20 weeks. The founders displayed osteosarcomas, proliferative lesions of the thyroid, salivary glands and nasal epithelium as well as an unusual form of chondrodysplasia. Therefore, the C3(1)-Tag construct used in these studies appears to lack regulatory regions required to limit expression exclusively to the prostate. In addition, the C3(1) transgene is responsive to both male and female sex hormones. In another case, mice carrying a truncated mouse mammary tumor virus long terminal repeat (MMTV-LTR)-int-2 cDNA construct were originally reported to exhibit a phenotype consistent with benign prostatic hyperplasia (Muller, Lee, Dickson, Peters, Pattengale, & Leder, 1990; Tutrone, Ball, Ornitz, Leder, & Richie, 1993). However, further histological evaluation has revealed the pathology actually occurs in the ampullary gland (G. Cunha, unpublished observations). When a fragment of the promoter for human prostate specific antigen (PSA) was used to target an activated Ha-ras oncogene to the prostate in transgenic mice, the mice developed salivary gland tumors with no apparent pathology in prostate gland (Schaffner, Barrios, Shaker, Rajagopalan, Huang, Tindall, et al., 1994). It is interesting to note that the promoter for the PSA gene, a member of the kallikrein gene family (Riegman, Vlietstra, van, Romijn, & Trapman, 1989), directed expression in salivary gland in transgenic mice since similar observations were not reported in previous transgenic studies using a kallikrein rKlK1 promoter Tag constructs (Smith, Lechago, Wines, MacDonald, & Hammer, 1992).

Transgenic mouse model for prostate cancer


Copper-based metallization is formed in a trench on an integrated circuit substrate by forming a liner of refractory metal in the trench using physical vapor deposition, forming a copper plating seed layer on the liner using physical vapor deposition and then plating copper on the copper plating seed layer. Prior to plating copper on the copper plating seed layer, the liner and/or copper plating seed layer is stuffed with hydrogen, for example by exposing the liner and/or copper plating seed layer to a hydrogen-containing plasma during and/or after formation of the liner and/or copper plating seed layer. Related structures also are disclosed.

Integrated circuit devices are widely used for consumer, commercial and other applications. As is well known to those having skill in the art, integrated circuit devices typically include a large number of active devices such as transistors in a microelectronic substrate, such as a semiconductor substrate. The devices are interconnected in a desired interconnection pattern using one or more levels of patterned conductor layers, often referred to as "metallization". As the integration density of integrated circuit devices continues to increase, copper-based metallization schemes have been developed to allow improved interconnect performance.
Copper interconnections are often formed using a damascene and/or dual damascene process, wherein trenches and/or vias are formed in one or more dielectric layers, overfilled with copper and then polished to remove the excess copper outside the trenches. Conventionally, a copper-based metallization is formed in a trench on an integrated circuit substrate by forming a liner that comprises refractory metal in the trench, forming a copper plating seed layer on the liner, and then plating copper on the copper plating seed layer. The refractory metal may be tantalum, although other refractory metals such as titanium and tungsten also may be used.
Conventionally, the liner includes a refractory metal nitride layer, such as a tantalum nitride layer, and a refractory metal layer, such as a tantalum layer, on the refractory metal nitride layer. The liner and the copper plating seed layer may be fabricated using physical vapor deposition and/or chemical vapor deposition.
As is well known to those having skill in the art, vapor deposition refers to processes in which materials in a vapor state are condensed through condensation, chemical reaction and/or conversion, to form a solid material. Vapor deposition processes may be classified into physical vapor deposition and chemical vapor deposition.
In physical vapor deposition, a thin film of material is deposited on a substrate by converting the material into vapor by physical means, transporting the vapor across a region of low pressure from its source to the substrate, and causing the vapor to undergo condensation on the substrate to form the thin film. Sputtering is a widely used physical vapor deposition method for integrated circuit fabrication. In sputtering, atoms are dislodged from the surface of a material as a result of collision with high energy particles. The atoms or molecules that are ejected from the target material condense on the substrate as a thin film.
In contrast, chemical vapor deposition refers to formation of a solid film on a substrate from a reaction of vapor phase chemical reactants containing the desired constituents. A reaction chamber is used for this process, into which reactive gases are introduced, to decompose and react with the substrate to form a film. Thus, in chemical vapor deposition, a predefined mix of reactant gases and diluent inert gases are introduced at a specified flow rate into a reaction chamber. The gas species move to the substrate, and the reactants are adsorbed to the surface of the substrate. The reactants undergo chemical reactions with the substrate to form the film. Atomic layer deposition is one form of chemical vapor deposition in which a film is deposited one atomic or molecular layer at a time.
In forming a liner with tantalum and/or tantalum nitride, it is known that these materials may be oxidized by adsorbed water during processing, according to the following chemical reactions:

This oxidation can degrade the adhesion between the liner and the subsequently formed copper layers, which can degrade the reliability of the interconnects by creating voids, as described, for example, in Yatsuta et al., Quantitative Control of Plasma-Surface Interactions for Highly Reliable Interconnects, Proceedings of the IEEE 2004 International Interconnect Technology Conference, Jun. 7-9, 2004, pp. 90-92. These voids may cause electromigration problems in the interconnect.
It is also known that enough hydrogen partial pressure can reduce or suppress the reaction between Ta/TaN and water, as shown by the following reactions:

Accordingly, it is known to perform a hydrogen-containing plasma treatment on a copper-based metallization system, by exposing the plated copper layer to a hydrogen plasma treatment, before depositing a subsequent dielectric layer. This hydrogen pretreatment may be performed at 350° C. after chemical mechanical polishing is performed on the integrated circuit substrate to remove the plated copper, the copper seed layer and/or the liner layer outside the trench, but prior to forming a subsequent dielectric layer on the copper-filled trenches.
It has been found that the hydrogen pretreatment of the copper layers in the trenches can provide electromigration lifetime improvements of up to 5 to 10 times or more. Unfortunately, however, this increase in electromigration lifetime may be accompanied by an undesirable increase in leakage current and/or line resistance of the copper metallization.

Physical vapor deposition methods for forming hydrogen-stuffed trench liners for copper-based metallization


A digital-to-analog (D/A) converter provides superior linearity and reduces glitches by setting optimum dimensions for MOS transistors. The D/A converter is configured from a R-2R ladder circuit and a switching circuit. The R-2R ladder circuit consists of series resistors (R) and shunt resistors (2R), which are connected together at respective nodes corresponding to the bit stages. The switching circuit is configured from MOS transistors which are connected between reference potentials and the shunt resistors for each bit stage. The width/length (W/L) ratios of the MOS transistors are set such that the on-resistances of the transistors are sequentially increased by a factor of 2 in bit-stage descending order from the most significant bit (MSB) to the least significant bit (LSB) to maintain the linearity of the R-2R ladder circuit. Dummy gates are provided in parallel to the MOS transistors, except for the MOS transistors which correspond to the MSB, so that the same effective gate capacitance is set for each bit stage to provide uniform switching speed for each stage avoiding the occurrence of glitches.

This invention relates to digital-to-analog converters which use R-2R ladder circuits (or R/2R ladder network).
FIG. 5 shows an example of a digital-to-analog converter (simply, a D/A converter) which is used in semiconductor LSI circuits (where `LSI` is an abbreviation for `Large Scale Integration`). The D/A converter of FIG. 5 is configured using a R-2R ladder circuit 1 which contains series resistors (R) and shunt resistors (2R). The D/A converter of FIG. 5 is designed as a 4-bit converter. A node of a series resistor R corresponding to a most significant bit (MSB) provides an analog output Aout. The series resistors 2R are connected to terminals (or nodes) N1 to N4 respectively. Connections of the terminals N1 to N4 are switched over by a switch-over circuit 2 such that the terminals N1 to N4 are connected to a positive potential terminal of a first reference potential Vref(+) or a negative potential terminal of a second reference potential Vref(-). The switch-over circuit 2 is controlled by bits IN1 to IN4 of a 4-bit digital input. Herein, IN4 denotes the most significant bit (MSB), while IN1 denotes the least significant bit (LSB).
The switch-over circuit 2 is configured by MOS transistors Q11 to Q41, which are connected between the terminals N1 to N4 and the positive potential terminal of Vref(+), as well as MOS transistors Q12 to Q42, which are connected between the terminals N1 to N4 and the negative potential terminal of Vref(-), wherein `MOS` is an abbreviation for `Metal-Oxide Semiconductor`. All of the MOS transistors are configured as n-channel MOS transistors of the enhancement type. There are provided two stages of inverters, i.e., I11 to I41 and I12 to I42. Those inverters receive the bits IN1 to IN4 respectively to produce signals which are in reverse phases to each other. The signals selectively switch on or off the MOS transistors.
A node of the series resistor R corresponding to the LSB is connected to the negative potential terminal of Vref(-) via a resistor 2R. To obtain a balance of resistance in consideration of the ON-resistances of the MOS transistors Q11 and Q12, a n-channel MOS transistor Q5 is provided between the resistor 2R and the negative potential terminal of Vref(-). Herein, the n-channel MOS transistor Q5 is normally biased in an ON state.
The operating principle of the D/A converter is well known. An analog output voltage Aout is obtained in accordance with an equation as follows: EQU Aout={(1/2)IN4+(1/4)IN3+(1/8)IN2+(1/16)IN1}.times.(Vref(+)-Vref(-))
Depending on the construction of the circuit elements, the resistors of the R-2R ladder circuit may be out of balance due to the ON-resistances of the MOS transistors of the switch-over circuit 2. So, there is a potential problem in that the linearity in the conversion characteristic of the D/A converter may be deteriorated. To obtain the superior linearity in the conversion characteristic of the D/A converter, it is ideal to use MOS transistors whose ON-resistances are negligible. Such a MOS transistor whose ON-resistance is negligible requires a relatively large area in channel width. This limits damages the highly integrated state of the LSI circuit. In addition, high gate capacity of the MOS transistor is required. Such high capacity limits the high-speed performance of the MOS transistor, which acts as a circuit element to switch over the connections.
To obtain a balance of resistance of the R-2R ladder circuit 1, it is preferable that the shunt resistors 2R are designed by giving consideration to the ON-resistances of the MOS transistors in advance. It may be relatively easy to accurately produce a resistance ratio of "1/2" with respect to the R-2R ladder circuit 1 by controlling resistances of the resistor elements only. That is, pattern measurements of the resistor elements are controlled to be "1/2". However, it is difficult to accurately realize a resistance ratio of 1/2 with respect to the circuit elements, containing the resistor elements and MOS transistors, in consideration of the ON-resistances of the MOS transistors.
If dispersion occurs at the operating speeds of the MOS transistors comprising the switch-over circuit 2, the aforementioned D/A converter suffers from another problem. That is, beard-like voltage pulses, called "glitches ", occur on an output voltage waveform due to deviations in the switch-over timings.

Digital-to-analog converter utilizing MOS transistor switching circuit with accompanying dummy gates to set same effective gate capacitance


A method and apparatus for providing geographically authenticated electronic documents is disclosed. Authentication for attributes for an electronic document stored on a computer network are defined, the attributes comprise at least one attribute describing a geographic location associated with the electronic document. Authenticated attributes (e.g., geographic location) of electronic documents (e.g., Web pages) allow for more accurate geographic searching and filtering. An authenticated digital certificate is created and associated with an electronic document. The authenticated digital certificate can be stored within the electronic document, such as can be done with HTML tags on a Web page. The digital certificate can also be stored as a separate file associated with the electronic document, as a separate signed digital certificate and as a database record.

This invention relates generally to enhanced searching techniques for electronic documents, and more specifically to the authenticating of electronic documents, referenced by electronic document addresses associated with geographic locations used in searching.
Searching for a particular electronic document on a network based upon geographic location currently presents many problems. For example, searching to find an HTML document on the World Wide Web associated with a geographic location returns many false positives (electronic documents not really associated with the geographic location specified) while also resulting in many misses (electronic documents not found that really are associated with the geographic location). The enormous number of electronic documents on the World Wide Web (it is estimated that 2.2 million Web sites offer 300 million Web documents) multiplies the problem of false positives in a geographic based search.
Keyword-based geographic searching functionality, such as GeoSearch by Vicinity Corporation (used on www.northernlight.com) provides some geographic restricted search capability. In these systems a keyword search based upon the geographic location specified is executed, then the user's location is determined and found electronic documents that are determined to be within a predefined range of the user are reported. The user's location is usually determined by querying the user for their city, state, country or zip code information. The geographic location of the electronic documents is determined by a specialized keyword parsing algorithm designed to identify addresses within electronic documents. Simply finding keywords that indicate an electronic document contains an address does not guarantee that the address corresponds to a geographic location associated with the electronic document. For example, when searching for a list of electronic documents related to "stores selling books in Boston, Mass." many false positives are possible, including electronic documents listing "books I read while in Boston, Mass.". Additionally, stores that do not format their addresses in such a way as to be recognized by the geographic keyword searching algorithm, or exclude their address completely, will not be reported. On the World Wide Web these electronic documents are referenced by electronic document addresses in the form of a Uniform Resource Locator ("URL").
Another approach to searching for electronic documents associated with geographic locations is the use of "online yellow pages" type functionality. In these systems a directory of business names is created that is searchable and sortable using geographic location. Providers of online yellow pages directories solicit data from prospective businesses and provide a searchable online listing for the businesses. Typically, the listing includes a name, address and phone number and is searchable by business name or business category. Yellow page directories typically exclude non-business entities (e.g., schools, government offices). Some services provide a URL if the business has a Web site. An exemplary online yellow pages site is www.yellowpages.com.
Yet another approach is the creation of "localized" portals (e.g., www.ca.yahoo.com for Yahoo! Canada) and "city pages" (e.g., www.citysearch.com) which restrict their content to that associated with a specific, predetermined, geographic area. These portals allow users to restrict searches to a preselected geographic region (e.g., Canada), but the regions tend to be countries or large, well populated, cities. These localized portals and city pages are typically built by human operators indexing Web pages associated with the specific, predefined geographic location.

Method and apparatus for providing geographically authenticated electronic documents


A heat sink retention apparatus includes a frame having a first end and a second end. A rotatable shaft is mounted on the frame. A heat sink retention arm is provided on the shaft and is rotatable with the shaft between a lock position and an unlock position. A driven member is provided on the shaft. The driven member includes a slot and a plurality of grooves. A rotatable driving member is mounted on the frame adjacent the driven member. A tab on the driving member engages the slot for rotating the driven member in response to rotation of the driving member. A plurality of arcuate members on the driving member engage the grooves in response to rotation of the driving member. As a result, the retention arm is movable between the lock position and the unlock position.

The disclosures herein relate generally to a computer system and more particularly to retention of a heat sink for cooling the computer system.
As the speed of computer microprocessors continues to increase, the heat that they are generating increases. Heat dissipating bodies such as heat sinks are often used to cool microprocessors. Faster processors are requiring larger, heavier heat sinks whose weight can cause the computer board to bend and flex when the heat sink is mounted to the board and when the board is subject to shock and vibrations while mounted to the computer chassis. Flexing of the computer board can be extremely damaging to the traces and components on the board.
Increased processor power has demanded heavier heat sinks and stronger heat sink clips and fasteners. Presently used clips require a large amount of force to open and close. In addition, if a clip is incorrectly installed, damage to the motherboard may result.
The use of higher force clips causes ergonomic issues for manufacturing personnel. As a result, an installation tool may be needed to supply a needed mechanical advantage. This can create a problem for field service repair needing the tool for removal and replacement.
In order to preserve contact between the processor and the heat sink, some clips create a large amount of preload force.
One approach has used metal leaf springs placed on each side of the heat sink and attached to a plastic base. This approach creates an accessibility issue inside the chassis creating multiple areas that need to be accessed in order to assemble and disassemble the heat sink.
Another approach is a metal clip that spans across the middle of the heat sink and attaches to the socket. This creates a single contact area on the sink which permits the sink to wobble. This approach is no longer feasible because the newer sockets are too small.
Therefore, what is needed is a heat sink retention apparatus which provides sufficient retention during shock events, and which provides an optional thermal interface between the heat sink and a processor with which the heat sink is engaged.
One embodiment, accordingly, provides a torsionally originated force to retain a heat sink. To this end, a frame has a first end and a second end. A rotatable shaft is mounted on the frame. A heat sink retention arm is provided on the shaft and is rotatable with the shaft between a lock position and an unlock position. A driven member is provided on the shaft. The driven member includes a slot and a plurality of grooves. A rotatable driving member is mounted on the frame adjacent the driven member. A tab on the driving member engages the slot for rotating the driven member in response to rotation of the driving member. A plurality of arcuate members on the driving member engage the grooves in response to rotation of the driving member. As a result, the retention arm is movable between the lock position and the unlock position.
A principal advantage of this embodiment is advantage of this embodiment is reduced manufacturing time and easy access for repair or replacement. The torsion spring also provides a preload on the processor socket and limits tolerance stack-up of the processor.