To increase the adhesion strength of coagulated blood on a surface by increasing the surface interaction of blood-inherent components like fibrin/fibrinogen and thrombocytes it is described to treat the surface by exposing it to ionized atoms or molecules. The surface treatment according to the invention is applied on plastic disposables used in blood diagnostics (e.g. hemostasis analysis) as well as medical implants like artery sealings. The improved blood clot adhesion results in higher diagnostic security due to reduced measurement failure (e.g., for patients with increased thrombocyte content) and in better significance of special tests (e.g., hyperfibrinolysis diagnosis).

It is essential for survival that a wound stops bleeding, i.e. that the body possesses an adequate mechanism for hemostasis. The process of blood clotting can be activated in the case of injuries or inflammations by either extrinsic or intrinsic factors, e.g. tissue factor (TF) or Hagemann factor (F XII), respectively. Both activation channels are continued in a common branch of the cascade resulting in thrombin formation. The thrombin itself finally initiates the formation of fibrin fibers, which represent the protein backbone of blood clots.
Various methods have been introduced to assess the potential of blood to form an adequate clot and to determine the blood clots stability. One group of tests is summarized by the term "viscoelastic methods". The common feature of these methods is that the blood clot firmness (or other parameters dependent on it) is continuously determined, from the formation of the first fibrin fibers, till the dissolution of the blood clot by fibrinolysis. Blood clot firmness is a functional parameter, which is important for hemostasis in vivo, as a clot must resist blood pressure and shear stress at the site of vascular injury. Clot firmness results from multiple interlinked processes: coagulation activation, thrombin formation, fibrin formation and polymerisation, platelet activation and fibrin-platelet interaction and can be compromised by fibrinolysis. Thus, by the use of the viscoelastic monitoring all these mechanisms of the coagulation system can be assessed.
The publications and other materials referred to herein to illustrate the invention and, in particular, to provide additional details respecting the practice are incorporated herein by reference.
The first viscoelastic method was called "thrombelastography" (Hartert H: Blutgerinnungsstudien mit der Thrombelastographie, einem neuen Untersuchungsverfahren. Klin Wochenschrift 26:577-583, 1948). In the thromboelastography, the sample is placed in a cup that is periodically rotated to the left and right by about 5°. A pin is freely suspended by a torsion wire. When a clot is formed it starts to transfer the movement of the cup to the pin against the reverse momentum of the torsion wire. The movement of the pin is continuously recorded and plotted against time.
The fibrin backbone creates a mechanical, elastic linkage between the two surfaces of the blood-containing cup and a pin plunged therein. A proceeding coagulation process induced by adding one or more activating factor(s) can thus be observed. In this way, various deficiencies of a patient's hemostatic status can be revealed and used for proper medical intervention.
Modifications of the original thromboelastography technique (also called thromboelastometry) have been described by Cavallari et al. (U.S. Pat. No. 4,193,293), by Do et al. (U.S. Pat. No. 4,148,216), by Cohen (U.S. Pat. No. 6,537,819), by Hartert et al. (U.S. Pat. No. 3,714,815) and by Calatzis et al. (U.S. Pat. No. 5,777,215).
A common feature of all the methods used for coagulation diagnosis is that the blood clot is placed between two cylindrical bodies and the ability of the blood clot to couple those two bodies is determined. However, the measurement can only be evaluated as long as the fibrin network is sufficiently bound to the surfaces of these two bodies, i.e. of cup and pin. If the fibers tear off even partly, the disturbed measurement becomes hard to interpret because of interference between this effect and the pathologic pattern of hyperfibrinolysis. Unfortunately, such tear-offs of the fibrin network can occur in the case of increased thrombocyte concentrations as observable for example in the blood of hematologic patients (thrombocytosis). In these patients the strength of the blood clot is enhanced and this can lead to too strong forces on the plastic surface, which can tear the clot off the material. For that reason, an enhancement of the blood-clot adhesion strength would improve the therapeutic security considerably.
The original cup and pin material used for thromboelastometry during the forties until the seventies was stainless steel. These cups and pins were cleaned between measurements and reused.
When thromboelastometry was developed most devices used in the medical laboratory were reused and were usually made of steel, other metals, glass or other durable materials. During the sixties and seventies most of these devices have been exchanged by disposable items made of plastic. These plastic parts are usually economically produced by injection moulding or equivalent techniques.
Disposable cups and pins for the use in thromboelastometry have been described in U.S. Pat. No. 4,148,216 by Do et al and in U.S. Pat. No. 5,223,227 by Zuckerman. In the U.S. Pat. No. 5,223,227 a production process for the cup and pin material is disclosed, which involves a roughening process of the moulds used for the injection moulding of the cups and pins. Roughening of the mould is the common strategy for enhancing the surface roughness of plastic parts produced by injection moulding. In the U.S. Pat. No. 5,223,227 mechanically roughening of the mould by sand-blasting is described.
The approach of roughening the mould to roughen the surface of the cup and pin to thereby enhance the adhesion of blood on the surface of the cup and the pin has several disadvantages:
The blood-plastic interaction takes place especially in a microscopic range of the single plastic and of the fibrin molecules. In contrast, the roughness produced by the injection moulding process is in a much larger range. Because of this the plastic surfaces produced by injection moulding provide only a limited adhesion of the blood clot. This may be sufficient for the analysis of normal blood, but may be inadequate when factors are present in the blood which compete with the adhesion of fibrin onto the plastic surfaces.
To obtain a reproducible adhesion of blood on a surface it is important to have a reproducible surface roughness.
However, the surface roughness of the injection mould changes during long-term use of the mould and also varies when a new mould has to be produced, or when several cavities are used for the production of the same part (in multi-cavity injection moulding tools).
The process for reaching an identical surface roughness on an injection moulding tool compared to previously applied tools can be very expensive and time-consuming. Several surface modifications may need to be performed, sample parts have to be produced and evaluated.
In addition, the surface properties produced by injection moulding vary depending on several injection moulding parameters (pressure, temperature) as well as by the batch of the plastic material applied.
The need for improved blood-clot anchoring at artificial surfaces also exists for implants or special artery sealings. In both cases the surface properties must allow a sufficient adhesion of coagulated blood. In the case of implants the blood clot serves as a scaffold for tissue regeneration. Although most polymeric surfaces show in general a good ability to bind blood-inherent coagulation components like thrombocytes and fibrin, the maximum tearing force is not adequate in the case of higher blood pressures or vascular motions. In view of this, improvements of the blood anchoring ability at artificial surfaces enable the use of highly sufficient vascular sealings.
In conclusion a method to improve the adhesion strength of blood clots onto plastic surfaces for diagnostic as well as for biomedical uses is highly desirable.
In the last decade, a rather overwhelming number of plasma applications to enhance the biocompatibility of medical devices in blood contact was disclosed (e.g. U.S. Pat. No. 6,159,531; U.S. Pat. No. 5,591,140; U.S. Pat. No. 5,262,451). These attempts were made to reduce the common blood affinity of artificial surfaces, thus preventing disadvantageous blood clotting and/or tissue deposition. The reported applications contain surgical equipments and in-vivo implants as well as disposables for blood storage or diagnostic purposes.
From U.S. Pat. No. 5,344,611 it is known to treat the surface of, e.g. polystyrene parts with plasma, to further accelerate the clotting activation of blood in contact to surfaces made from such polymers.
There remains a need for a device to the surface of which a blood clot adheres with high adhesion strength. There is also a need for a method for preparing a surface such that the adhesion of a blood clot or to a clot of blood components to the surface is enhanced. In addition, there is a need for a device for more reliable coagulation analysis.
The present invention is directed to a method of treating the surface of a device which is to be coupled to a clot of blood or to a clot of blood components, a device which is to be coupled to a clot of blood or to a clot of blood components and a device for coagulation analysis.
The method of treating the surface is especially advantageous in that the blood adhesion strength of a clot of blood or blood components on a surface is increased compared with an untreated surface.
The device for coagulation diagnosis has, among others, the advantage over other devices that coagulation properties of blood or blood components can also be measured reliably in case of abnormal blood properties which is of high value in such a device.

Device with novel and improved surface properties


This invention is for an improvement in amplifiers resulting in ultra low distortion. It relates to amplifiers consisting of three stages, an input stage which amplifies an input signal and provides a first signal to an intermediate stage which amplifies the first signal and provides a second signal to an output stage which amplifies that second signal and provides an amplifier output signal, the amplifier further including a power supply to provide power to the three stages and wherein the low distortion is achieved by the output stage including output transistors connected to provide the amplifier output signal and further including an error correction means that comprises an input buffer means, an adding means, a subtracting means and a voltage follower buffer means wherein the adding means sums the second signal with a difference signal to produce an output sum signal the said output sum signal fed to the voltage follower buffer means which then provides a buffered output sum signal, which is then fed to the inputs of the output transistors and to the subtracting means, the amplifier output signal is also fed to the subtracting means which is adapted to subtract the amplifier output signal from the buffered output sum signal to produce a difference signal and a first bootstrap power supply to provide power to the error correction means, the bootstrap power supply closely tracking the output signal by means of bootstrapping.

Most amplifiers consist of three stages:
1. An input stage, normally a differential voltage to current converter stage, in which current variations are relatively small; PA1 2. followed by an intermediate stage whose output may produce large voltage variations and about which the amplifier's dominant pole is often formed; PA1 3. which is then followed by an output stage most often in the form of a voltage follower.
All three stages produce distortion which affects the signal to be amplified, the output stage usually being the worst.
Throughout this specification the following descriptions are used:
The input signal to the amplifier is termed an "amplifier input signal" and is supplied to an "amplifier input", which is used to denote the input of an "input stage" adapted to amplify the amplifier input signal and to provide a "first signal."
The first signal is fed to a next stage, termed an "intermediate stage" which is adapted to amplify the said first signal and further adapted to provide a "second signal." The second signal is fed to an input of an "output stage" adapted to amplify the said second signal and further adapted to provide an "amplifier output signal" to an "amplifier output."
A "power supply means" is adapted to provide power to the input stage, the intermediate stage and the output stage.
A review of the current state of the art in low distortion has been given by D. Self in a series of articles in "Electronic World+Wireless World" from August 1993 to January 1994. In these articles distortions in each of the three stages as set out above are described and current best methods for achieving low distortion are discussed.
The D. Self articles discussed above recommended that the first stage is a differential voltage to current converter, followed by an intermediate stage about which the dominant amplifier pole is formed. This intermediate stage is a cascade amplifier feeding a constant current source so that distortion from the well known "Early effect" is avoided. Buffer transistors are inserted between the output transistors and the intermediate stage. The lowest distortion is achieved by using a symmetrical complementary bi-polar transistors in the output stage, where the one half is a driver-npn-cum-power-pnp pair configured with a large measure of local negative feedback and the other half is similarly a driver-pnp-cum-power-npn pair configured with a large measure of local negative feedback. The Self articles also recommends and teach certain circuit layouts so that spurious sources of distortion causing mechanisms may be avoided.
The lowest combination of distortion as taught by those articles gives a total harmonic distortion of about 10 parts per million (10 ppm) at 1 kHz and a little over 100 ppm at 20 kHz. However this was measured in a amplifier of very modest power, namely 10 watts. These figures are thought to be consistent with the best state-of-the-art low distortion amplifiers presently commercially available and possible from currently known techniques.


A rotating speed detecting apparatus has: a bearing sensor configured to detect rotation of a motor and output detection pulses whose frequency depending on a rotating speed of the motor; and a calculating unit configured to receive the detection pulses from the bearing sensor. The detection pulses include a first pulse and a second pulse output next to the first pulse. The calculating unit calculates a revolution of the motor from a pulse interval between the first pulse and the second pulse.

1. Field of the Invention
The present invention relates to a rotating speed detecting apparatus. In particular, the present invention relates to a rotating speed detecting apparatus having a bearing sensor.
2. Description of the Related Art
A sensor for detecting rotation of a motor has been known in the past. The sensor outputs detection pulses indicating that the rotation of the motor is detected. For example, the sensor outputs thousands of detection pulses when the motor makes one rotation. A calculating unit connected to the sensor receives the detection pulses, and is able to calculate a revolution (rotating speed) of the motor based on the number of the received detection pulses. The calculated revolution is used for controlling a vehicle equipped with the motor.
FIG. 1 is a figure for explaining a conventional method of calculating the rotating speed. Output pulses (output pulse group) output from the sensor are shown in FIG. 1. According to the conventional technique, the revolution of the motor is calculated (estimated) by counting the number of the output pulses in a predetermined sampling period. The count value becomes larger, as the motor rotates at a higher speed. The count value becomes smaller, as the motor rotates at a lower speed. However, there is a problem with the conventional technique in that computation error of the calculated revolution becomes larger as the rotating speed of the motor becomes lower. For example, let us consider a case where the count value of the output pulses is 8. In this case, a certain revolution is calculated by the calculating unit. However, an actual revolution is different between in a case where the revolution is calculated immediately after the eighth output pulse is output and in a case where the revolution is calculated immediately before the ninth output pulse is output. Therefore, the calculated revolution may differ greatly from the actual revolution.
Moreover, accuracy of the calculation of revolution also depends to the number of pulses (referred to as a "pulse number" hereinafter) output during the motor makes one rotation. The pulse number with regard to a typical sensor is, for example, 1000 to 2000. However, the pulse number with regard to a "bearing sensor" consisting of ball bearings and a pulse sensor is at most 100 to 200 because of its structure. In a case where the revolution of the motor is the same, the typical sensor associated with the large pulse number outputs more detection pulses than the bearing sensor associated with the small pulse number, as shown in FIG. 1. Therefore, when the bearing sensor is used, the number of pulses which the calculating unit receives during a sampling period is relatively small and hence the error of the calculated revolution is increased. In particular, when the motor rotates at a low speed, the number of pulses which the calculating unit receives becomes extremely small and thus the error of the calculated revolution becomes extremely large. This is not preferable from the viewpoint of the stable control of the vehicle.
Meanwhile, the above-mentioned bearing sensor is favorable in terms of cost and size. For example, a battery forklift is often equipped with the bearing sensor having a small pulse number. In this case, the cost can be reduced, and a large working space for an operator of the battery forklift can be obtained. It is desired to improve stability of a vehicle equipped with the bearing sensor such as the forklift. It is particularly desired to improve the stability when the vehicle runs at a low-speed.
Japanese Laid-Open Patent Application (JP-A-Heisei, 10-38906) discloses a technique relating to the detection of the rotating speed. According to the technique disclosed in the patent document, a pulse width of a pulse signal is detected at a predetermined calculation timing on the basis of a middle edge calculating method. When a change in a pulse signal has been detected, the pulse width of the pulse signal is measured at the calculation timing. On the other hand, when a change in a pulse signal has not been detected, the pulse width of at the calculation timing is estimated on the basis of a difference between the latest pulse width and the previous pulse width.


Test structures and methods for superconducting bump bond electrical characterization are used to verify the superconductivity of bump bonds that electrically connect two superconducting integrated circuit chips fabricated using a flip-chip process, and can also ascertain the self-inductance of bump bond(s) between chips. The structures and methods leverage a behavioral property of superconducting DC SQUIDs to modulate a critical current upon injection of magnetic flux in the SQUID loop, which behavior is not present when the SQUID is not superconducting, by including bump bond(s) within the loop, which loop is split among chips. The sensitivity of the bump bond superconductivity verification is therefore effectively perfect, independent of any multi-milliohm noise floor that may exist in measurement equipment.

"Flip chip" fabrication, also known as controlled collapse chip connection (C4), is a manufacturing method for interconnecting semiconductor devices, such as integrated circuit (IC) chips, to external circuitry with balls of solder, called "bump bonds," deposited onto chip pads on the top side of a first chip near the end of a wafer process used to fabricate the first chip. To mount the first chip to external circuitry (e.g., a circuit board or a second chip or wafer), the first chip is flipped over so that what was initially its top side during its own fabrication faces down, and then is aligned so that its pads align with matching pads on the external circuitry. The solder is then reflowed to complete the interconnect. Flip chip fabrication stands in contrast to wire bonding, in which a chip is mounted upright and wires are used to interconnect the chip pads to external circuitry. Flip chip processes are used in making traditional CMOS devices, and now also in the construction of superconducting circuit devices that typically operate in refrigerated cold spaces at temperatures of around 4 kelvins or less.

Superconducting bump bond electrical characterization


Compositions and methods for the treatment of Chlamydial infection are disclosed. The compositions provided include polypeptides that contain at least one antigenic portion of a Chlamydia antigen and DNA sequences encoding such polypeptides. Pharmaceutical compositions, vaccines and diagnostic kits are also disclosed.

Human infections caused by the obligate intracellular pathogen Chlamydia trachomatishave a marked impact on human health. C. trachomatis serovariants are the leading cause of bacterial sexually transmitted disease and infectious preventable blindness. Despite decades of effort, there is no practical vaccine against C. trachomatis diseases.
C. trachomatis is an obligate intracellular bacterial pathogen that colonizes and infects oculogenital mucosal surfaces. The organism exists as multiple serovariants that infect millions of people worldwide. Ocular infections cause trachoma, a chronic follicular conjunctivitis that results in scarring and blindness. WHO estimates that 300-500 million people are afflicted by trachoma (1), making it the most prevalent form of infectious preventable blindness (2). Urogenital infections are the leading cause of bacterial sexually transmitted disease (STD) in both industrialized and developing nations (3). Moreover, STD are risk factors for infertility (4), the transmission of HIV (5) and human papilloma virus induced cervical neoplasia (6). Control of C. trachomatis infections is an important public health goal. However, aggressive measures aimed at managing these infections have not altered incidence or disease severity (7). Thus, there is a need in the art for effective control of chlamydial diseases (8).

The United States of America, as represented by the Secretary, Department of Health & Human Services


An impregnated carbon film expanded into a honeycomb structure is employed in a tapered notch phased array antenna and is used to absorb cross-polarized incident fields to reduce the reflections from shorted TEM parallel plate modes existing between radiator elements of the antenna. The carbon loading used to achieve this absorption may comprise a resistive taper, or analog circuit or anisotropic elements having a predetermined tapering resistive profile. The honeycomb cross-polarized load of the present invention provides the electrical performance necessary to meet tapered notch phased array antenna electrical requirements while reducing the weight and cost of antennas in which it is employed.

The present invention relates to ferrite load devices, and more particularly, to honeycomb cross-polarized loads for use in tapered notch phased array antennas.
The present approach of the assignee of the present invention to active phased array antenna technology employs the use of tapered notch radiators. Currently, a tapered ferrite load is used to absorb a cross-polarized field incident on the tapered notch radiators. Such conventional ferrite loads have been employed in trough regions between linear arrays of the tapered radiators that make up a phase array antenna, but it has been found that these components are relatively heavy due to their relatively high density.
It would therefore be an improvement in the art to have a component that is capable of absorbing the cross-polarized field incident on tapered notch radiators of a tapered notch phased array antenna that provides the same or improved performance when compared to conventional ferrite loads, but which reduces the weight and cost of the load.


The present invention provides a method for measuring a two-dimensional distribution of ionizing radiation doses with high spatial resolution. The method comprises exposing radiation sensitive film to a pattern of ionizing radiation to form a measurement film, exposing areas of radiation sensitive film to a plurality of known doses of the ionizing radiation to form a calibration film(s), scanning all the exposed films together with an unexposed radiation sensitive film at a single time to produce a digital image, measuring those areas of the digital image corresponding to the unexposed film and the calibration film(s) exposed to different known doses, associating the measured responses in the areas to the known doses and using the association to convert the values in the scanned image corresponding to the measurement film from scanner response values to dose values. In a preferred embodiment, all of the radiation sensitive films are the same type of film.

The present invention relates to an efficient method for radiation sensitive film dosimetry, and in particular, to methods for measuring a distribution of ionizing radiation doses.
Radiotherapy has been used for years as a method for irradiating and selectively killing cancer cells while minimizing radiation exposure to adjacent tissue. The effectiveness of radiotherapy depends upon the absorbed dose or the amount of energy deposited within a tissue mass. Absorbed dose is typically measured in centigray or cGy units.
A radiation detection medium may be used to determine the amount and location of radiation to which a patient is subjected during radiation treatment. Particularly useful is a two-dimensional radiation detection medium that can determine radiation dose over an area. Examples are radiographic film, radiochromic film, phosphor plates, two-dimensional arrays of diodes or ion chambers and the like. The radiation detection medium typically has a response that varies systematically in accordance with the degree of radiation exposure. After exposure to ionizing radiation, radiation detection media such as radiographic and radiochromic films typically have a light transmission or optical density that varies systematically in proportion to the radiation dose. Calibration of the radiation sensitive film allows one to measure the absorbed dose indirectly by measuring the light transmission or optical density of the exposed radiation detection medium.
Radiochromic films are widely used by Medical Physicists to perform radiation dosimetry. Film is widely recognized as a "gold standard" for performing radiation dosimetry because of its exceptional spatial resolution, reaching to a level of at least 0.025 mm. Such high resolution is not possible with other measurement modalities including ion chambers, diodes and TLD. These other techniques are limited to spatial resolution in the range of 1 mm or coarser. Another advantage of radiochromic film is its tissue equivalence that the adsorbed radiation dose is truly reflection of the dose adsorbed by tissue.
Calibration curves for a radiation detection medium are often prepared by exposing one or more areas of the detection medium to different and known amounts of radiation using a linear accelerator or a similar device capable of generating a range of known dose levels. Another method frequently used is to expose the detection means to a continuously varying level of doses. This can be done by interposing a wedge of material with continuously varying thickness between the radiation source and the detection medium. Alternatively, the radiation sensitive medium may be sandwiched between two blocks and positioned so that the medium is in a plane parallel to the beam when it is exposed. In this configuration the dose applied to the radiation sensitive medium decreases continuously with depth below the top surface of the blocks. This type of exposure is often referred to as a depth-dose exposure. Typically, calibration curves are generated by measuring the response of the radiation sensitive medium for numerous different dose levels. In the instance of radiation films, it is common to measure the light transmission or optical density of the medium for numerous different radiation dosage levels.
Until now, a disadvantage of dosimetry with radiochromic film relative to the use arrays of ion chambers and diodes, is that it is less time-efficient. For example, commercial devices comprising arrays of ion chambers or diodes are commonly used to validate intensity modulated radiotherapy treatment (IMRT) plans delivered by linear accelerators. The time needed to set-up the array device on a linear accelerator, make the measurement, compare the measured values with the treatment plan and then pack up the device is of the order of 30 to 40 minutes. On top of this is an overhead for calibration of the array. However, this overhead is small since the array may be calibrated only once every few months during which time dozens of validation measurements would be made.
For a number of reasons it has required a significantly longer time to do a similar measurement using radiochromic film. Also, the use of film has brought other inconveniences. Firstly, the calibration of radiochromic film can be inefficient in that new production lots of film require new calibration. —The time required to set up and expose film to an IMRT plan is less than is required for the array devices. However, once the film has been exposed it must be scanned on a film digitizer and then the scan data must be processed to produce a measurement result. Usually a measurement with film will have required multiple scans and on top of that the scanning must be done at a well regulated time-after-exposure corresponding to the time-after-exposure of the calibration film. The restriction of time-after-exposure is due to the fact that the polymerization reaction initiated by the exposure continues after the exposure at a rate that diminishes with time. In practical terms this meant that several hours elapsed between exposure and scanning, meaning that the results of the measurement are only available after a considerable and inconvenient time delay. In total, the time required for the film measurement can be as much as 3× the time required to make measurements with the array devices.
As alluded to above, though the spatial resolution of a single ion chamber or diode is on the order of 1 mm, the array devices can comprise many hundreds or even a few thousand devices, but in order to cover a large area, typically 400-1000 cm2, the individual sensors can be 5-10 mm apart, severely decreasing the spatial resolution of the array device. Since these devices are used to validate treatment plans calculated at a resolution of 1 mm, or better, the array devices are not sufficient to their function.
Having spatial resolution orders of magnitude better than 1 mm, radiochromic dosimetry film could be the best choice for dose measurement and radiotherapy treatment plan validation if it were more convenient and faster to use.

Efficient method for radiochromic film dosimetry


In a data storage subsystem providing data storage to host processors, a process of configuration defines a subset of the data storage that each host may access. A vector specification is a convenient mechanism for specifying a set of storage volumes that a host may access. For example, for each host processor, there is stored in memory of the data storage subsystem a list of contiguous ranges or vectors of the storage volumes that the host may access. To determine whether or not a specified logical volume number is included in the vector, a mudulus of the stride of the vector is computed from the difference between the address of the specified logical volume and the beginning address of the vector, and the modulus is compared to zero. To provide a mapping between logical unit numbers specified by the host and the logical volumes, a contiguous range of logical unit numbers may also be specified for each contiguous range or vector of storage volumes. The logical volume number is computed from a specified logical unit number by computing a difference between the specified logical unit number and the beginning logical unit number, multiplying the difference by the stride of the vector to produce a product, and adding the product to the beginning address of the vector.

1. Technical Field
The present invention relates generally to data processing networks and data storage subsystems, and more particularly to a data processing network in which a number of hosts can access volumes of data storage in a data storage subsystem.
2. Description of the Related Art
Due to advances in computer technology, there has been an ever increasing need for data storage in data processing networks. In a typical data processing network, there has been an increase in the number of volumes of data storage and an increase in the number of hosts needing access to the volumes. This has been especially true for networks of workstations. Not only have a greater number of workstations been added to the typical network, but also the increase in data processing capabilities of a typical workstation has required more data storage per workstation for enhanced graphics and video applications.
The increased demand for data storage in a network is typically met by using more storage servers in the network or by using storage servers of increased storage capacity and data transmission bandwidth. From the standpoint of cost of storage, either of these solutions appears to be satisfactory. However, a greater number of storage servers in a network substantially increases the cost of managing the storage. This increased cost of management often appears some time after installation, when one of the servers reaches its capacity and some of its volumes must be reassigned to less heavily loaded servers. Network administrators aware of the cost of storage management realize that network storage should be consolidated to the minimum possible number of servers. The management problem is reduced by reducing the number of objects to be managed.
Due to the storage needs of present networks and the desire to consolidate servers, it is practical to provide a single storage subsystem with up to 20 terabytes (TB) storage, or approximately 4000 logical volumes. It may be possible for any host to have access to any volume in a data storage subsystem to which the host has access. However, it may be desirable to restrict the set of volumes that can be seen by any one host. Restricted access is desirable for security of private data. For example, private volumes should be assigned to each host for storage of private data, and other hosts should not be permitted to see or modify the private volumes of other hosts. Moreover, the xe2x80x9cbootxe2x80x9d process for a host is slowed down by searching for and reporting all the volumes to which the host has access. Certain operating systems are limited by the number of storage devices that they can manage at a given period of time, and for a host running such an operating system, it is not only desirable but also necessary to limit the number of volumes that the host can access.
It is possible to restrict access of a host to a limited set of logical volumes in the data storage subsystem by restricting the set of logical volumes accessible through a particular port adapter of the storage subsystem and linking the host to only that particular port adapter. For convenience, however, there should not be any restrictions on which logical storage volumes are accessible from each port adapter. Otherwise, during a reconfiguration of the data processing system, it may be necessary to physically switch the links that are connected to the network ports of the hosts or the port adapters, for example by manually disconnecting and reconnecting the links to the ports. Even in the case where the data network has a fabric for automatically establishing a link between any of the hosts and any of the port adapters, the physical possibility of any port adapter to access any logical storage volume provides alternative data paths that could be used in case of port adapter failure or port adapter congestion. For example, if a host sends a data access request to a port adapter and receives a busy response from the port adapter, then the host can send the data access request to another port adapter. Port adapter congestion is likely, for example, if the storage subsystem is a continuous media server, in which video data is often streamed through a single port adapter to a host for a relatively long period of time.
In accordance with one aspect of the invention, there is provided a method of configuring data storage in a data storage subsystem for restricting access of host processors to the data storage. The method includes subdividing the data storage into addressable logical storage units, and assigning to each host processor a respective subset of the data storage to which access of said each host processor is restricted. The assignment of at least one respective subset includes at least one vector specification of a series of the addressable logical storage units. The addressable logical storage units in the series of addressable logical storage units having addresses that form a vector. The vector includes a beginning address (BEGIN) and a stride (S) that is a difference between neighboring addresses of the addressable logical storage units in the series of addressable logical storage units, such that the addresses of the logical storage units in the series are BEGIN, BEGIN+S, BEGIN+2S, . . . , and wherein the stride (S) is a non-zero integer different from one.
In accordance with another aspect, the invention provides a data storage subsystem. The data storage subsystem includes data storage, and a storage controller coupled to the data storage for controlling access to the data storage. The storage controller has at least one data port for linking the data storage to a plurality of host processors for transfer of data between the data storage and the host processors. The storage controller is programmed to access addressable logical storage units of the data storage, and to restrict access of the host processors to the data storage by assigning to each host processor a respective subset of the data storage to which access of the host processor is restricted. The assignment of at least one respective subset includes at least one vector specification of a series of the addressable logical storage units. The addressable logical storage units in the series of addressable logical storage units have addresses that form a vector. The vector includes a beginning address (BEGIN) and a stride (S) that is a difference between neighboring addresses of the addressable logical storage units in the series of addressable logical storage units, such that the addresses of the logical storage units in the series are BEGIN, BEGIN+S, BEGIN+2S . . . S , and wherein the stride (S) is a non-zero integer different from one.
In accordance with a final aspect, the invention provides a machine-readable program storage device containing a program for a storage controller for controlling access of a plurality of host processors to data storage. The program is executable by the storage controller to access addressable logical storage units of the data storage, and to restrict access of the host processors to the data storage by assigning to each host processor a respective subset of the data storage to which access of said each host processor is restricted. The assignment of at least one respective subset includes at least one vector specification of a series of the addressable logical storage units. The addressable logical storage units in the series of addressable logical storage units have addresses that form a vector. The vector includes a beginning address (BEGIN) and a stride (S) that is a difference between neighboring addresses of the addressable logical storage units in the series of addressable logical storage units, such that the addresses of the logical storage units in the series are BEGIN, BEGIN+S, BEGIN+2S . . . , and wherein the stride (S) is a non-zero integer different from one.

Configuring vectors of logical storage units for data storage partitioning and sharing


An image display apparatus which is subjected to getter flashing during manufacturing, for the purpose of increasing the degree of vacuum in the air-tight container thereof, is provided with a getter scattering prevention member comprised of a plurality of getter scattering prevention walls. The getter scattering prevention walls prevent getter material from scattering to the image display portion of the image display apparatus, while allowing for smooth conductance of gas in the air-tight container during evacuation. Thus, evacuation by the getter can be further improved by increasing the area to which getter adheres to, deterioration of the image quality can be prevented by not allowing getter to adhere to the image display portion, the air-tight container can be evacuated in a shorter time, irregularities in brightness of the screen due to uneven pressure within the display portion can be done away with, and a higher degree of vacuum can be attained. Consequently, an image display apparatus with good image quality and a long life expectancy is provided.

1. Field of the Invention
The present invention relates to a flat-type image display apparatus, and particularly to an image display comprising getter and a getter scattering preventive member.
2. Related Background Art
There have been known image display apparatuses such as those using liquid crystal, electron beam, EL (electro-luminescence), and of these the most commonly used image display apparatus for television is that employing the cathode-ray tube.
Television apparatuses using a cathode-ray tube generally have a disadvantage in that the depth of the apparatus is great in comparison to the size of the screen, thereby limiting the locations at which the television apparatus may be placed. Accordingly, in recent years, there has been research conducted on flat-type image display apparatuses which use electron beams, this arrangement requiring less depth of the apparatus than such employing the cathode-ray tube.
While flat-type image display apparatuses are smaller in volume than such employing cathode-ray tubes, the amount of gas emitted from the fluorescent material is great. Accordingly, a high level of skill is required to raise the degree of vacuum within the image display apparatus and further maintain that state.
Generally, in order to maintain the state within the sealed envelope at a high degree of vacuum, getter is employed. There are two types of getter; evaporation type, and non-evaporation type. With the evaporation type getter, the getter material is stored within an open container, following which this getter material is heated by means of conductive heating or electrical induction heating or the like, thus causing the getter material to evaporate (this process hereafter referred to as xe2x80x9cflashingxe2x80x9d), thereby causing the getter material to adhere to the interior of the envelope, consequently removing the gas from the airtight container. The non-evaporation type involves getter material being stored within an open container, following which the gas from is removed from the airtight container without causing flashing.
FIGS. 20A and 20B illustrate on e example of the structure of a known vacuum fluorescent display tube as disclosed in Japanese Patent Publication No. 56-44534, with FIG. 20A being a plan view, and FIG. 20B being a cross-sectional view along the line denoted by 20Bxe2x80x9420B in FIG. 20A.
As illustrated in FIG. 20B, this known example comprises a face plate 1601 composed of insulating material such as glass serving as an image display screen, and a rear plate 1602 set so as to oppose the face plate 1601. The area of contact between the face plate 1601 and the rear plate 1602 is sealed by means of glass with a low melting point, supersonic soldering, or resin which hardens in the presence of ultraviolet rays.
Further, a getter scattering prevention wall 1608 which doubles as a filament support is provided within this envelope so as to face the face plate 1601 and the rear plate 1602 in a generally vertical manner, and to this getter scattering prevention wall 1608, getter 1605 is fixed. Further, on the face plate 1601 situated on the other side of the getter scattering prevention member 1608 from the side provided with getter, a plurality of display units are arrayed, with each display unit comprising an image pattern 4, a control grid 1610 for controlling the content of the image, and a filament 1609. The getter scattering prevention wall 1608 is provided so that the getter material from the getter 1605 does not pass over to the image display unit side. Incidentally, reference numeral 9 in FIGS. 20A and 20B denotes a getter film, this formed by means of flashing of the getter 1605.
The image display apparatus constructed as described above is generally evacuated by means of connecting a turbo molecular pump or the like to an evacuation tube (not shown) and evacuating, and when the degree of vacuum within the envelope reaches a sufficient level, the evacuation tube is sealed by means of being stopped and severed, following which the getter 1605 is flashed, thus completing the image display apparatus.
After completion of the image display apparatus, heating the filament (thermionic cathode) 1609 causes electrons generated by means of the heating to be accelerated by means of an anode comprising an image pattern 4 (not shown), and strike fluorescent material (not shown) comprising an image pattern. Consequently, an image is displayed on the face plate 1601.
On the other hand, Japanese Laid-Open Patent Application No. 61-32336 mentions that with a flat-type image display apparatus, the amount of metal, glass, and ceramic comprising the electrode structure is several times that of a cathode-ray tube, whereas the area to which getter can be deposited to by flashing is less. Particularly, the inner wall area of the glass container is markedly smaller with a flat-type image display apparatus as compared to a cathode-ray tube. Accordingly, within the Japanese Laid-Open Patent Application No. 61-32336 is disclosed a fibrous shielding member such as steel wool or steel wool coated with graphite, for the purpose of increasing the area to which getter can be deposited by flashing, and preventing the getter subjected to flashing from passing over to the electrode structure or wires, causing short-circuiting between the electrodes or wires. This fibrous member is placed, for example, continuously or intermittently around the space formed between the inner wall of the glass container and the rear side of the electrode structure, i.e., the space where evaporation deposition of the getter is conducted, thus limiting the spread of the getter which attempts to pass over, and also increasing the area to which deposition of getter occurs by means of causing evaporation deposition of the getter to the surface of the shielding member.
However, known image display apparatuses constructed as described above have problems such as described below.
(1) Narrowing the distance between the outer edges of the getter scattering prevention wall and the outer frame, or increasing the density of the fibrous shielding material, as is done with known art, decrease the flowability of residual gas, i.e., the conductance thereof, to the getter flashing area within the envelope. In such an event, the capability of the getter may not be sufficiently exhibited, or modifications in the brightness of the image may occur due to the pressure being uneven within the envelope. Further, this lengthens the amount of time required to evacuate the container via the evacuation tube.
(2) Widening the distance between the outer edges of the getter scattering prevention wall and the outer frame, or decreasing the density of the fibrous shielding material improves the conductance, but the getter material may pass over to the image display portion via the gap between the getter scattering prevention wall and the outer frame or via the gaps in the fibrous shielding material, thus adhering to the electron emission source or fluorescent material, and possibly causing short-circuiting of the wiring.
(3) Further, in the case of flat-type image display apparatuses, the area occupied by the electron emission source and the area occupied by the fluorescent material are often approximately the same, and moreover, the distance between the electron emission source and the fluorescent material corresponding to the depth of the CRT is around several hundred xcexcm to several tens of mm.
Accordingly, the area capable of placement of getter within the flat-type image display apparatus is markedly reduced compared to that of the CRT, although the area of getter adhesion required therein is equal to or greater than that of the CRT, due to the degree of vacuum required being equal to or greater than that of the CRT. Consequently, it becomes important to secure area for placement of getter therein, increasing the amount of getter placed, and also preventing the aforementioned getter from passing over.
The present invention has been made to solve the aforementioned problems with the known art, and accordingly, it is an object of the present invention to provide an image display apparatus with a high degree of vacuum and a long working life expectancy, wherein the area to which getter adheres is great, the time require to evacuate the envelope by means of the evacuation tube is short, vapor evaporation of the getter is conducted without the getter material passing over to the image display portion, evacuation following sealing of the evacuation tube is conducted efficiently by means of the getter, and wherein pressure modifications within the image display apparatus do not occur.
According to an aspect of the present invention, there is provided an image display apparatus comprising: a face plate carrying fluorescent material; a rear plate situated so as to oppose the face plate; an outer frame disposed between the aforementioned face plate and rear plate, the outer frame being bonded to both plates, thus forming an envelope comprised of the aforementioned face plate, rear plate, and outer frame; fluorescent material excitation means situated within the aforementioned envelope; evaporation type getter situated within the aforementioned envelope at a position other than the position at which the aforementioned fluorescent material excitation means and getter are situated; and a plurality of getter scattering prevention walls provided as a means to prevent the getter evaporating from the aforementioned evaporation type getter from scattering to the portion within the aforementioned envelope where the fluorescent material and fluorescent material excitation means are situated.
Providing the getter scattering prevention member according to the present invention between the getter flashing portion and the image display portion provides the below-described advantages.
1. The getter material that has evaporated from the getter scatters radially in all directions. While the getter material has properties of adhering to walls with which collision occurs, rather than being deflected from the walls, molecules or atoms comprising gas are deflected from any walls they may collide with, and do not adhere to these walls. To be more precise, these molecules or atoms are not completely deflected with absolutely no adhesion whatsoever; a certain amount adheres thereto, depending on the gas, wall material, temperature, etc. The present invention takes advantage of the difference in properties between the getter material and gas, and provides a plurality of getter scattering prevention walls arrayed so that there is no linear optical path between the getter flashing portion where the getter is situated and the image display portion. Accordingly, there is no passing over of getter material to the display portion, thus avoiding undesirable effects such as shorting of wiring or undesirable effects to the electron-emitting devices and fluorescent material. Consequently, pixel defects owing to getter, which are fatal to the quality of an image display apparatus, are eradicated. Further, since there is no passing over of getter material as described above, there is no restriction to the image pattern (screen size) within the display area, as with known-apparatuses which have taken into account beforehand the passing over of getter. Rather, according to the present intention, the entirety of the image dispay area can be employed as image pattern (screen size), thus allowing for a larger and more imposing screen on an image display apparatus of the same size.
2. Particularly, in the event that a getter scattering prevention member is constructed of a plurality of plates forming a getter scattering prevention wall, the number of getters to be situated needs only be restricted by mechanical concerns, since there is no restriction regarding the direction of getter flash. Accordingly, a great number of getters may be deployed. Further, the total area of the face plate, rear plate, outer frame, and getter scattering prevention walls of the getter flashing portion are subject to getter material adhesion, thus effectively securing a large getter area, so that evacuation by means of getter can be conducted for a long period of time.
3. As described above, the getter material that has evaporated from the getter scatters radially in all directions. While the getter material has properties of adhering to walls with which collision occurs, rather than being deflected from the walls, molecules or atoms comprising gas are deflected from any walls they may collide with, and do not adhere to these walls. To be more precise, these molecules or atoms are not completely deflected with absolutely no adhesion whatsoever; a certain amount adheres thereto, depending on the gas, wall material, temperature, etc. The present invention takes advantage of the difference in properties between the getter material and gas, and provides a plurality of getter scattering prevention walls arrayed so that there is no linear optical path between the getter flashing portion where the getter is situated and the image display portion. Accordingly, the gas is capable of freely passing through the paths between walls neighboring the aforementioned walls, and can reach the getter flashing portion from the image display portion. Further, the paths neighboring the aforementioned walls are constructed throughout the entire area, so that conductance is good. Moreover, the conductance can be designed and controlled, so that the amount of time required for evacuation by means of the evacuation tube is shortened.
Accordingly, manufacturing costs of image display apparatuses can be lowered greatly. Further, conductance is good as described above, so that pressure distribution within the image display apparatus is reduced, the amount of time required for evacuation of gas which is generated from the fluorescent material and the like upon driving the apparatus, this evacuation conducted by means of getter, is shortened, and as a result, an image display apparatus wherein modifiedities in brightness and discharge are suppressed can be provided.
According to the above-described, an image display apparatus can be provided with a long working life expectancy, one which is stable over a long period of time, having high quality with no pixel defects or brightness modifiedities, and at a low cost.


A mixture of particulate silicone based material and small hollow elements, such as spheres and/or fibers, is provided. The particulate silicone based material is heated to a temperature between about 200° F. and about 400° F. The particulate silicone based material is cooled until a solid body is formed. The solid body is resistant to melting and thermal decomposition when heated to temperatures of at least 3000° F. The solid body may contain cavities formed by the small hollow elements. The solid body may contain reinforcing fibers. The solid body may contain both small hollow elements and fibers.

The casting of metal articles using sand molds and sand cores is well known in the art. A sand mold can be made from a mixture of sand and an organic binder by packing the mixture loosely or tightly around a pattern. The pattern is then removed, leaving a cavity in the sand that replicates the shape of the pattern. Once the organic binder is shape-stabilized by a curing technique, the cavity in the mold is filled with a molten metal by pouring the molten metal into the mold.
Sand mold cores can be made by placing a sand and binder mixture into a core box. There, the sand and binder mixture takes the shape of the cavity in the box, becomes hard, and is removed. After the mold is made, the core is then set in the mold. Molten metal is poured in the mold and fills the mold except where the sand core is present.
The binder materials used in making the sand molds, and sand cores can include inorganic binders, organic binders, and organometallic binders. Oraganometallic binders are uniquely suited for use as binders for sand molds and sand cores because they provide strength to the sand molds and sand cores at extremely low binder levels. Additionally, organometallic binders can be used to bind particles together to make shapes directly.
U.S. Pat. No. 5,884,688 discloses a method of fabricating shaped bodies such as negatives of parts to be made, as well as, shapes directly. The method comprises coating sand with liquid organic-metallic binder, forming a shape from said binder mixture, and hardening said binder mixture to form the shaped body. One organometallic binder is a polyureasilazane.
U.S. Pat. No. 5,552,466 discloses a method of producing an article with high temperature and thermal shock resistance comprising forming a blend of at least one lower viscosity silicone polymer. The blend is disclosed as being "cermitizable" at a temperature above about 1100° F. (590° C.). An article, formed in accordance with the patent, contains a layer of material formed from a silicone blend.

Heat resistant material for molds and other articles


Self-service recovery of application data. A list of recoverable objects for the application is generated in response to the receipt of a request for an application recovery from a user. The list of recoverable objects for the application is sent to the user. A selected recoverable object from the user is received. In response, the execution of a recovery job on the backup and restore application is initiated for the selected recoverable object.

With the increased specialization of roles and workloads in organizations, there are more and more instances of application owners being different than the backup and recovery owners. In these situations, it becomes increasingly difficult to coordinate between the application owners and the backup owners to define and meet the organization's data protection and recovery SLAs (Service Level Agreements).
Application owners often invest in and manage their own backup systems with little or no coordination with the backup team in their organization. In turn, the complexity, cost and points of failure of an organization wide protection SLAs are increased. For example, a large number of database administrators perform their own backups and expect the backup team to back up these files using the enterprise backup tools.


The present disclosure, for example, relates to one or more techniques for linearizing a signal in a communications system. An input signal may be obtained at a beginning of a signal path of a radio frequency (RF) communication device. The RF communication device may estimate subsequent distortion of the input signal due to the signal path. The estimated distortion may include estimated phase distortion and estimated amplitude distortion of the input signal. The RF communication device may adjust phase and amplitude within the signal path to compensate for the estimated phase distortion and the estimated amplitude distortion to produce an adjusted signal. The phase within the signal path of the input signal may be adjusted separately from the amplitude within the signal path of the input signal. The RF communication device may generate a linearized signal at an end of the signal path based at least in part on the adjusted signal.

The present disclosure, for example, relates to communications systems, and more particularly to linearizing signals in a radio frequency (RF) communications system.
Transmitters and receivers of a RF communications system may employ amplitude and phase modulation of a signal. The signal being modulated may become distorted in the transmitter or receiver due to various factors. For example, components of the transmitter or receiver may experience non-linear behaviors when first switched on. The non-linear behavior of the components may cause amplitude and phase distortion of the signal. The amplitude and phase distortion may result in less reliable or slower communication between the transmitter and receiver, as the communication may be dependent upon accurate amplitude and phase modulation.
The phase and amplitude of the signal may be adjusted in the transmitter or receiver to overcome the distortion. For example, the phase and amplitude of the signal may be shaped so that a resulting signal exhibits linear amplitude and phase characteristics. A signal having linear amplitude and phase characteristics may allow for improved reliability and speed of communications between the transmitter and receiver.
Conventional approaches for shaping phase and amplitude may involve complex pre-distortion or feedback schemes to overcome the non-linear behavior of the components of the transmitter or receiver. In these approaches, the shaping of the amplitude and phase may be coupled. A change in amplitude may result in a change in phase, and a change in phase may result in a change in amplitude. This coupling may cause increased difficulty in maintaining both linear amplitude and linear phase at the same time. Therefore, it may be expensive and difficult to overcome the phase and amplitude distortion in transmitters and receivers.

This patent is subject to a terminal disclaimer.

Techniques for linearizing phase independently of amplitude in a communications system


In one aspect, the present invention generally provides methods for fabricating substrates for use in a variety of analytical and/or diagnostic applications. Such a substrate can be generated by exposing a semiconductor surface (e.g., silicon surface) to a plurality of short laser pulses to generate micron-sized, and preferably submicron-sized, structures on the surface. The structured surface can then be coated with a thin metallic layer, e.g., one having a thickness in a range of about 10 nm to about 1000 nm.

The present invention relates generally to methods for fabricating substrates suitable for use in analytical and diagnostic optical systems, and in particular, substrates for use in Raman spectroscopy.
Raman spectroscopy can be employed as an analytical as well as a diagnostic technique in a variety of applications, such as material characterization and identification. It relies on inelastic scattering of incident photons by a molecule, via coupling to its vibrational modes, to provide an essentially unique signature for that molecule. In particular, such inelastic scattering (commonly known as Raman scattering) can cause a decrease or an increase in the scattered photon energy, which appear as "Stokes" and "anti-Stokes" peaks in a wavelength-dispersed spectrum of the scattered photons. A drawback of Raman spectroscopy is the relatively few incidences of such inelastic scattering. The probability that a scattering event will occur is typically called "cross-section," which is expressed in terms of area.
Raman scattering cross-sections can, however, be significantly enhanced by placing the molecule on or near a conductive surface. Such a mode of performing Raman spectroscopy is commonly known as surface enhanced Raman spectroscopy (SERS). Although SERS is a promising technique for extending the use of Raman spectroscopy to a variety of new applications, its use is currently limited due to a dearth of reliable, high performance substrates.
Accordingly, there is a need for substrates for use in SERS, as well as other applications, that can provide a high degree of reliability and performance. There is also a need for methods of fabricating such substrates with a high degree of reproducibility, which can be easily and, preferably inexpensively, implemented.

Metalized semiconductor substrates for raman spectroscopy


A generally T-shaped clip is fit into notches formed in the field shell of a permanent magnet D.C. motor. The clip has a passageway formed through its top surface for receiving a screw or the like to secure the field shell to a surrounding tool housing. The notches have a top portion with an elongated portion that has a concave inner side to abut the outer surface of the field shell and retain the clip in the notches. The clip has a bottom portion that is bent so that it contacts the screw to prevent it from turning and loosening.

The use of universal motors, including a field coil and a stator coil, to operate various tools is well known in the art. The field coil is excited with an electrical current from a power source, such as a typical electrical outlet. The field coil then rotates to induce an electrical current in the stator coil and provide the necessary power to operate the tool. Universal motors are typically attached to the tool housing by mount screws that are screwed through both the motor housing and the tool housing.
Permanent magnet D.C. motors are also known for use in operating tools. The permanent magnet D.C. motors include a field shell with a plurality of permanent magnets attached to the inside of the shell. Centered within the field shell is an armature core. A commutator is located outside of the field shell and is connected to a pair of coil windings that provide electrical current to the armature core to drive the armature. Once the armature has begun rotating, the polarity of the permanent magnets and the resultant magnetic field, drive the armature such that a shaft extending out of the field shell is driven, thus driving the power tool.
The permanent magnet motor assembly cannot be drilled for mounting screws because of its thickness, thus other methods and apparatus for attaching the field shell of these motors to the motor housing have been utilized. These methods and apparatus typically extend from the sides or the ends of the permanent magnet motors thus taking up valuable space. These methods and apparatus are also time consuming and expensive to manufacture.

Field retaining mechanism for a permanent magnet D.C. motor


Methods of enzymatically resolving acyloxyalkyl thiocarbonates useful in the synthesis of acyloxyalkyl carbamate prodrugs are disclosed.

The oral bioavailability of certain drugs can be improved by conversion to prodrugs. Certain prodrugs are derivatives of the parent drug in which a functional group is "masked" by a promoiety. Following administration to a patient the prodrug is metabolized to release the parent drug. The 1-(acyloxy)-alkyl group is an example of a promoiety that has been used to functionalize amine-containing drugs such as pregabalin and baclofen.
Pregabalin ((3S)-(aminomethyl)-5-methyl-hexanoic acid) is an FDA approved drug that is marketed for the treatment of, for example, post herpetic neuralgia, peripheral diabetic neuropathy, fibromyalgia, and epilepsy. Pregabalin is not absorbed from the lower gastrointestinal tract and exhibits a short half life in vivo, and therefore frequent dosing is required to maintain therapeutic levels in the body when orally administered. (3S)-{[1-Isobutanoyloxyethoxy]carbonylaminomethyl}-5-methyl-hexanoic acid, (3S)-{[1-isobutanoyloxyisobutoxy]carbonylaminomethyl}-5-methyl-hexanoic acid, and (3S)-{[1-benzoyloxyethoxy]carbonylaminomethyl}-5-methyl-hexanoic acid are examples of 1-(acyloxy)-alkyl carbamate prodrugs of pregabalin, which exhibit high bioavailability as pregabalin when dosed either orally or directly into the colon of a mammal (Gallop et al., U.S. Pat. Nos. 6,972,341 and 7,186,855; and Yao and Gallop, U.S. Provisional Application Nos. 61/023,808 filed Jan. 25, 2008 and 61/023,813 filed Jan. 25, 2008, each of which is incorporated by reference in its entirety).
The 1-(acyloxy)-alkyl promoiety has also been used to provide prodrugs of baclofen, (±)-4-amino-3-(4-chlorophenyl)butanoic acid. Gallop et al., U.S. Pat. No. 7,109,239 and U.S. Pat. No. 7,300,956 (each of which is incorporated by reference in its entirety) disclose 1-(acyloxy)-alkyl carbamate prodrugs of R-baclofen such as (3R)-4-{[(1S)-2-methyl-1-(2-methylpropanoyloxy)propoxy]carbonylamino}-3-(4-chlorophenyl)butanoic acid. Baclofen is an analog of gamma-aminobutyric acid (GABA) that selectively activates GABAB receptors, resulting in neuronal hyperpolarization. Baclofen is an FDA approved drug that is marketed for the treatment of spasticity and muscle relaxation. More recent studies have indicated that the R-isomer of baclofen is effective for treating gastroesophageal reflux disease (GERD). Baclofen and R-baclofen, like pregabalin, have poor colonic absorption and a short half life in vivo, and when orally administered frequent dosing is required to maintain therapeutic levels in the body.
The (acyloxy)alkylcarbamate functionality has been widely used to prepare prodrugs for therapeutics containing amine groups (Gogate et al., International Journal of Pharmaceutics 1987, 40, 235-248; Alexander et al., J. Med. Chem. 1988, 31, 318-322; Sun et al., Bioorganic & Medicinal Chemistry Letters 2001, 11, 1875-1879; Alexander et al., J. Med. Chem. 1991, 34, 78-81; and Gallop et al., U.S. Pat. No. 6,972,341). Methods of synthesizing 1-(acyloxy)-alkyl carbamate prodrugs are disclosed in Gallop et al., U.S. Pat. Nos. 6,818,787, 6,927,036, 6,972,341, 7,186,855, 7,026,351, 7,109,239, and 7,227,028; Raillard et al., U.S. Pat. No. 7,232,924; Gallop and Bhat, WO 2005/010011; Raillard et al., U.S. Provisional Application No. 61/087,056 filed Aug. 7, 2008 and 61/087,038 filed Aug. 7, 2008, each of which is incorporated by reference in its entirety); and in Alexander, U.S. Pat. Nos. 4,760,057, 4,916,230, and 5,684,018. One method, as outlined in FIG. 1, involves an acyloxyalkylthiocarbonate intermediate (Sun et al., Bioorganic & Medicinal Chemistry Letters 2001, 11, 1875-1879; and Gallop et al., U.S. Pat. Nos. 7,026,351 and 7,227,028).
A deficiency common to such methods for synthesizing acyloxyalkyl derivatives is that, except when the R2 substituent is hydrogen, the prodrugs are generated as racemates or diastereomeric mixtures. The presence of an additional chiral center in the promoiety may lead to differences in the physical properties and in the pharmacokinetics of the prodrug. Complexities associated with the introduction of an uncontrolled stereocenter in acyloxyalkyl promoieties have led others to focus prodrug design efforts around the achiral acyloxymethyl moiety (R2 is hydrogen). Further, many (acyloxy)alkylcarbamate prodrugs generate formaldehyde as a toxic metabolite during hydrolysis in vivo. In comparison with acetaldehyde, formaldehyde shows greater acute mammalian toxicity and mutagenicity, and its oxidative metabolite formate is associated with specific ocular toxicity in humans. Furthermore, because the thiocarbonates do not have acidic or basic functional groups, they are not readily resolved by classical chemical methods.
Thus, improved methods of synthesizing enantiomerically enriched acyloxyalkyl thiocarbonates are desirable.

Enantiomerically resolving acyloxyalkyl thiocarbonates used in synthesizing acyloxyalkyl carbamate prodrugs


The present invention is an electromechanical high load separation apparatus with a smooth release which can be utilized in various applications such as a structural separation mechanism for a nut/bolt, a cable release mechanism, or a replacement of cable cutters.

1. Field of The Invention
The present invention relates to the field of separation mechanisms. In particular, the present invention is an electromechanical high load separation apparatus with a smooth release which can be used in various applications such as a structural separation mechanism for a nut/bolt, a cable release mechanism, a replacement of cable cutters, etc.
2. Description of The Prior Art
Separation devices are widely used in manufacturing and construction industries. The main purpose of utilizing separation devices is to provide a release in a quick releasible manner of the external attached structure in a smooth manner without damaging the external structure. The following ten (10) prior art patents were uncovered in the pertinent field of the present invention:
1. U.S. Pat. No. 1,027,481 issued to Huff on May 28, 1912 for "Releasing Hook for Life Boats and the Like" (hereafter "the Huff Patent"). PA1 2. U.S. Pat. No. 1,190,491 issued to Dunn on Jul. 11, 1916 for "Coupling" (hereafter "the Dunn Patent"). PA1 3. U.S. Pat. No. 1,929,869 issued to Hissner on Oct. 10, 1933 for "Quick Change Chuck" (hereafter "the Hassner Patent"). PA1 4. U.S. Pat. No. 3,012,811 issued to Sandrock on Dec. 12, 1961 for "Gripping Tool" (hereafter "the Sandrock Patent"). PA1 5. U.S. Pat. No. 3,109,677 issued to Hoover on Nov. 5, 1963 for "Self-Releasing Grappling Device" (hereafter "the Hoover Patent"). PA1 6. U.S. Pat. No. 3,718,951 issued to Pasbrig on Mar. 6, 1973 for "Rope Clamp" (hereafter "the Pasbrig Patent"). PA1 7. U.S. Pat. No. 3,877,343 issued to Newell on Apr. 15, 1975 for "Stores Carriers" (hereafter "the Newell Patent"). PA1 8. U.S. Pat. No. 4,258,888 issued to Sawn on Mar. 31, 1981 for "Quick Releasing High Strength Connector" (hereafter "the Sawn Patent"). PA1 9. U.S. Pat. No. 5,064,235 issued to Lessard on Nov. 12, 1991 for "Automatic Sling Device" (hereafter "the Lessard Patent"). PA1 10. U.S. Pat. No. 5,131,705 issued to Glock on Jul. 21, 1992 for "Device for Remote-Controlled Grasping and Coupling" (hereafter "the Gluck Patent").
The Huff Patent discloses a releasing hook for life boats and the like. The releasing hook assembly includes two gripping jaws which are bounded by a sleeve. The sleeve is biased by a spring to hold two gripping jaws close to each other for gripping the head portion of a stem. The sleeve can be pulled against the spring force to allow the separation of the two gripping jaws, to thereby release the stem.
The Dunn Patent discloses a coupling tube which includes a series of internal jaws. The internal jaws are biased by a coil spring for coupling an inserted head portion of a wire. To release the wire, an external sleeve is inserted into the tube to separate the internal jaws so that the head portion of the wire can be pulled out.
The Hissner Patent discloses a quick change chuck. The quick change chuck assembly includes two locking levers which are bounded by a slidable ring. The slidable ring has internal cam surfaces engagable with the two locking levers. The slidable ring is biased by a coil spring for closing the locking levers to lock an inserted collar. When the slidable ring is slid against the spring force, the internal cam surfaces force the two locking levers to open for releasing the collar.
The Sandrock Patent discloses a gripping tool. The gripping tool has two grasping members which are pivotally mounted on the tool and operable by the up and down movement of a plunger. The plunger has a necked down portion for allowing the two grasping members to move closer or apart, depending on the moving direction of the plunger.
The Hoover Patent discloses a self-releasing grappling device. The grappling device includes two separable jaws for grappling a lifting lug. An external releasing sleeve is attached to the lifting lug and is utilized for engaging the two separable jaws and forcing them to open to release the lifting lug.
The Pasbrig Patent discloses a rope clamp. The clamp assembly includes two elongated clamping members which are bound by a clamping body and biased by a shackle spring. The elongated clamping members are further connected to a spring biased sleeve which can be shifted to allow the clamping members to move relatively with respect to the clamping body, so that the two clamping members are separated which allows the clamped rope to release.
The Newell Patent discloses a stores carrier. The carrier assembly includes two jaws having integral cams. The carrier assembly further includes rollers which can engage on the cam to close or open the jaws.
The Sawn Patent discloses a quick releasing high strength connector. The connector assembly includes a plurality of spring biased over-center dogs for holding a load. The over-center dogs are pivotally mounted and engaged by a spring biased latching ring to lock the load. By pulling a release cable, the latching ring can be lifted up to allow the over-center dogs to rotate for releasing the load.
The Lessard Patent discloses an automatic sling lock. The sling lock assembly includes two locking pawls which are controlled by two actuating rods respectively. The actuating rods are connected to a same butt plate which is biased by a spring.
The Gluck Patent discloses a remote-controlled grasping and couplingdevice. The grasping and coupling device includes two pivotally mounted load latches for holding an electrical plug connection. A slidable outer ring isprovided for binding the two load latches. The outer ring can be lifted up by a pair of forks to allow the load latches to rotate for releasing the electricalplug connection to a storage station.
It can be seen that various structures of the clamping or retaining members and spring biased sleeves have been utilized in the art. However, none of the prior art has disclosed the tiltable rocker which allows the releaseof the external structure upon actuation of any one of the two initiators. However, in many aerospace apparatus such as satellites, it is highly desirable to utilize an electromechanical high load separation apparatus with asmooth release without damaging the highly sensitive external structure.
Therefore, it is highly desirable to have a very efficient and also very effective design and construction of an electromechanical high load separation apparatus with a smooth release which can be used in various applications such as a structural separation mechanism for a nut/bolt, a cable release mechanism, a replacement of cable cutters, etc.

Electromechanical high load separation apparatus with a smooth release


Methods for producing surface-emitting semi-conductor lasers with tunable waveguiding are disclosed. The laser comprises an active zone containing a pn-transition, surrounded by a first n-doped semiconductor layer and at least one p-doped semiconductor layer. In addition to a tunnel junction on the p-side of the active zone, the tunnel junction borders a second n-doped semi-conductor layer with the exception of an area forming an aperture. An n-doped layer is provided between the layer provided for the tunnel junction and the at least one p-doped semiconductor layer. The tunnel junction may be arranged in a maximum or minimum of the vertical intensity distribution of the electric field strength. This enables surface-emitting laser diodes to be produced in high yields with stabilization of the lateral single-mode operation, high performance and wave guiding properties.

Surface-emitting laser diodes or Vertical-Cavity Surface-Emitting Lasers (VCSEL) are semiconductor lasers, in which light emission occurs perpendicular to the surface of the semiconductor chip. Compared with conventional edge-emitting laser diodes the surface-emitting laser diodes have numerous advantages such as low electrical power consumption, the possibility of direct monitoring of the laser diode on the wafer, ease of coupling to a glass fiber, production of longitudinal single mode spectra and the possibility of connecting the surface-emitting laser diodes together to form a two-dimensional matrix.
In the field of fiberoptic communications technology—because of the wavelength-dependent dispersion or absorption—devices producing radiation in a wavelength range from about 1.3 to 2 μm, and in particular wavelengths of about 1.31 μm or 1.55 μm, are needed. Longwave laser diodes with useful properties, particularly for the wavelength range above 1.3 μm, have been produced from InP-based connecting semiconductors. GaAs-based VCSELs are suitable for the shorter wavelength range of less than 1.3 μm.
A continuous wave VCSEL which emits at an output of 1 mW at 1.55 μm has been constructed of an InP substrate with metamorphic layers or mirrors (IEEE Photonics Technology Letters, 11(6), June 1999, pp. 629-631). Lateral wave guiding is achieved by proton implanting.
A VCSEL produced in a single epitactic growth process with an output of 0.45 mW at a wavelength of 1.5 to 1.6 μm with a metamorphic mirror on the light emitting side is known from "High Performance 1.6 μm Single-Epitaxy Top-Emitting VCSEL", (Conference on Lasers & Electro-Optics (CLEO) 2000, San Francisco, USA, Post-Deadline Paper CPD 12, pp. 23-24). Current and wave guiding were achieved by selective oxidation.
A VCSEL with an air-semiconductor mirror (InP—air gap Distributed Bragg Reflectors (DBRs)) was proposed in IEEE ISLC 2002, pp. 145-146. A tunnel junction was applied between the active zone and the upper DBR mirror, whereby a current was achieved by under-etching the tunnel junction layer. The air gap surrounding the remaining tunnel junction area serves as a waveguide for the optical field.
A VCSEL with antimonide-based mirrors, in which an under-etched InGaAs active zone is enclosed by two n-doped InP layers, adjoined by AlGaAsSb-DBR mirrors, is known from the 26th European Conference on Optical Communication, ECOC 2000, "88° C., Continuous-Wave Operation of 1.55 μm Vertical-Cavity Surface-Emitting Lasers". The selective under-etching in this case brings about lateral wave guiding.
The optimum properties in terms of performance, operating temperature range, single mode power and modulation bandwidth, however, are found in VCSELs with buried tunnel junctions (BTJs). The manufacture and structure of the buried tunnel junction will be described hereinafter with reference to FIG. 1. A highly doped p+/n+ pair of layers 101, 102 with a small band spacing is produced by molecular beam epitaxy (MBE). The actual tunnel junction 103 is formed between these layers. By reactive ion etching (RIE) a circular or elliptical area is shaped, which is essentially formed by the n+-doped layer 102, the tunnel junction 103 and some or all of the p+-doped layer 101. This area is overgrown with n-doped InP (layer 104) in a second epitaxy procedure, so that the tunnel junction 103 is "buried". The contact area between the overgrown layer 104 and the p+-doped layer 101 acts as a barrier layer when voltage is applied. The current flows through the tunnel junction with resistances of typically 3×10−6 Ω cm2. In this way, the current flow can be restricted to the actual area of the active zone 108. Moreover, little heat is generated, as the current flows from a high-resistance p-doped layer to a low resistance n-doped layer.
The overgrowing of the tunnel junction leads to slight variations in thickness which have an unfavorable effect on lateral wave guiding, with the result that the production of higher lateral modes is made easier, particularly in the case of larger apertures. Therefore, only small apertures can be used with less corresponding laser power for single mode operation, which is required in fiber optic communications technology.
Examples and applications of VCSELs with buried tunnel junctions can be found, for example, in "Low-threshold index-guided 1.5 μm long wavelength vertical-cavity surface-emitting laser with high efficiency", Applied Physics Lett., 76(16), Apr. 17, 2000, pp. 2179-2181; in "Long Wavelength Buried-Tunnel-Junction Vertical-Cavity Surface-Emitting Lasers", Adv. in Solid State Phys. 41, 75-85, 2001; in "Vertical-cavity surface-emitting laser diodes at 1.55 μm with large output power and high operation temperature", Electronics Letters, 37(21), Oct. 11, 2001, pp. 1295-1296; in "90° C. Continuous-Wave Operation of 1.83 μm Vertical-Cavity Surface-Emitting Lasers", IEEE Photonics Technology Letters, 12(11), November 2000, pp. 1435-1437; and in "High-speed modulation up to 10 Gbit/s with 1.55 μm wavelength InGaAlAs VCSELs", Electronics Letters, 38(20), Sep. 26, 2002. Lateral wave guiding is provided in these examples by lateral variation in the resonator length.
The structure of the InP-based VCSEL discussed in the above-mentioned literature will be briefly explained below with reference to FIG. 2, starting from the structure of the buried tunnel junction in FIG. 1 described above.
The Buried Tunnel Junction (BTJ) in this structure is arranged in reverse relative to FIG. 1. The active zone 106 is situated above the tunnel junction having a diameter DBTJ determined by the p+-doped layer 101 and the n+-doped layer 102. The laser radiation travels in the direction indicated by arrow 116. The active zone 106 is surrounded by a p-doped layer 105 (InAlAs) and an n-doped layer 108 (InAlAs). A front mirror 109 above the active zone 106 consists of an epitaxial DBR with 35 pairs of InGaAlAs/InAlAs layers, producing a reflectivity of about 99.4%. A rear mirror 112 consists of a stack of dielectric layers as DBRs and ends with a layer of gold, producing a reflectivity of nearly 99.75%. An insulating layer 113 prevents direct contact of the n-InP layer 104 with the p-end contact layer 114, which is generally comprised of gold or silver (in this context see DE 101 07 349 A1). Reference numeral 111 designates the p-end contact layer which is annular in structure.
The combination of the dielectric mirror 112, the integrated contact layer 114 and heat sink 115 results in a significantly increased thermal conductivity compared to epitaxial multi-layer structures. Current is injected through the contact layer 114 or through the integrated heat sink 115 and the n-end contact points 110. For further details of the manufacture and properties of the VCSEL types shown in FIG. 2, express reference is made to the literature mentioned above.
In the proposed VCSEL diodes, particularly for the wavelength range between about 1.3 and 2 μm, there is a need to be able to adjust the lateral radiation profile thereof within wide ranges by lateral wave guiding. Here, too, manufacturing should take place with the usual epitaxial overgrowth, and for this reason Al-free InP-based VCSELs, in particular, are suitable for wavelengths above 1 μm.
In GaAs-based VCSELs, which can only be used in wavelength ranges below about 1.3 μm, lateral wave guiding is produced by selectively oxidized AlAs layers (in this context see "Advances in Selective Wet Oxidation of AlGaAs Alloys", in IEEE Journal of Selected Topics in Quantum Electronics, 3(3), June 1997, pp. 916-926). The VCSEL discussed therein consists of multiple layers of GaAs—AlGaAs, produced epitaxially by Metal Organic Vapour Phase Epitaxy (MOVPE). By wet oxidation of the AlGaAs layers, buried oxide layers are formed which leave an unoxidized aperture open in the center of the VCSEL. This method has not hitherto been successfully applied to the InP-based VCSELs, as AlAs cannot be applied or can only be applied in layers that are too thin because of mismatching of the lattice constants, and other oxidizable materials such as, for example, AlGaSb have hitherto not produced an oxide layer of sufficient quality. Therefore, with long wave VCSELs, other methods of lateral wave guiding have been used, such as for example lateral variation of the resonator length, selectively etched layers, proton implanting or metamorphic AlAs layers, as explained above in connection with references cited.

Method for producing a waveguide structure in a surface-emitting semiconductor laser and surface-emitting semiconductor laser


A biological information detection device includes: a video capture unit, a blood flow analysis unit, a local pulse wave detection unit, a pulse wave propagation velocity calculation unit, and a blood pressure estimation unit. The video capture unit obtains video information on a face of a living body. The blood flow analysis unit analyzes video data of at least three skin areas in the video information, as blood flow information. The local pulse wave detection unit is provided for each skin area to calculate pulse information based on the blood flow information sequenced chronologically. The pulse wave propagation velocity calculation unit calculates a pulse wave propagation velocity based on a phase difference between pieces of the pulse information at each skin area calculated by the local pulse wave detection unit. The blood pressure estimation unit estimates blood pressure based on the pulse wave propagation velocity.

Such a technique has been attracting attention in recent years that the dynamic state of a living body is detected in real time using a microwave or a camera in a non-contact manner. For example, a technique of detecting the heart rate and the like, based on the temporal change of a subject's face video obtained by a camera, has been mounted on mobile terminals such as smartphones, along with a camera module being reduced in size, and has rapidly become popular. In addition, the technique has been evolved into a technique of measuring the blood pressure of a subject in real time using a smartphone or the like.
Japanese Patent Application Publication No. 2015-054223 A (hereinafter referred to as Patent Document 1), for example, discloses a technique of detecting pulse wave signals, from an imaged video for two portions of a subject, at the respective portions, to obtain a pulse wave propagation velocity from the pulse wave signals at the two portions, and estimating a subject's blood pressure based on a Moens-Korteweg blood vessel model and the relationship between elasticity of a blood vessel wall and blood pressure.

Biological information detection device, biological information detection method and non-transitory computer-readable storage medium for biological information detection


A method and apparatus are provided for monitoring a liquid level in a closed tank with a differential pressure sensor module disposed in a bottom portion of the tank, by routing a pressure reference tube extending from the pressure sensor module through the interior of the tank and attaching an opposite, open, vented end of the pressure reference tube to the tank at a point inside of the tank in an upper portion of the tank.

As shown in FIGS. 1 and 2, in one widely used approach to measuring the liquid level 10 in a closed tank 12, a differential pressure monitoring apparatus 14 includes a differential pressure sensor 16 attached by an umbilical cord 18 to a sensor housing 20 including a sealed closure 22 adapted for attachment to an opening, such as a bung-hole 24, located on an upper surface of the tank 12. The umbilical cord 18 has sufficient length to allow the differential pressure sensor 16 to lie on, or be suspended very close to the bottom of the tank 12 when the closure 22 of the monitor 14 is operatively sealing the opening 24 in the tank 12.
As shown in FIG. 1, the differential pressure sensor 16, of such prior monitoring apparatuses 14, have typically been electrical in nature, and have generated electrical signals which are transmitted through one or more electrical transmission elements 26, in the form of wires or metallic strips, which extend through the umbilical cord 18 from the pressure sensor 16 to a termination point on an electric circuit board 28 located within the housing 20 of the pressure monitoring apparatus 14.
A pressure reference tube 30 also extends through the umbilical cord 18 from the pressure sensor 16 to an open-ended termination point located inside of the housing 20. The housing 20 is typically vented to the atmosphere surrounding the housing 20 through a vent 32, which may include internal structures to preclude the entry of fluid into the housing 20, or provide a flame arrester, where volatile fumes or liquids may be involved.
By virtue of this arrangement, ambient air pressure surrounding the housing 20 is communicated through the vent 32 and the open end of the pressure reference tube 30 to the differential pressure sensor 16 located below the liquid level 10 in the tank 12. By sensing changes in differential pressure, the pressure sensor 16 is able to provide an output to the internal circuit 28 indicative of the fluid level 10 in the tank 12. In some instances, the circuitry 28 has included provisions for also determining changes in the level of the liquid 10 in the tank 12 over time, as a function of inputs received from the differential pressure sensor 16.
While such an approach works well in many applications, under certain conditions, and with certain fluids such as propane, it is desirable to have a differential pressure sensor monitor a difference in pressure between an upper, gas-filled portion 34 of the tank 12 and a lower, liquid-filled portion 36 of the tank 12.

Integral in tank vent construction for pressure based level monitors


Systems and methodologies are described that facilitate handing off from a first sector to a second sector. An established link to the first sector may be employed to communicate with the second sector. A handoff request from a wireless terminal to the second sector and an associated handoff response from the second sector to the wireless terminal may both traverse the first sector.

I. Field
The following description relates generally to wireless communications, and more particularly to handoff between access points or base stations in wireless communications.
II. Background
Wireless communication systems are widely deployed to provide various types of communication; for instance, voice and/or data may be provided via such wireless communication systems. A typical wireless communication system, or network, can provide multiple users access to one or more shared resources. For instance, a system may use a variety of multiple access techniques such as Frequency Division Multiplexing (FDM), Time Division Multiplexing (TDM), Code Division Multiplexing (CDM), and others.
Common wireless communication systems employ one or more base stations that provide a coverage area. A typical base station can transmit multiple data streams for broadcast, multicast and/or unicast services, wherein a data stream may be a stream of data that can be of independent reception interest to a wireless terminal. A wireless terminal within the coverage area of such base station can be employed to receive one, more than one, or all the data streams carried by the composite stream. Likewise, a wireless terminal can transmit data to the base station or another wireless terminal.
Handoffs between base stations and/or base station sectors commonly occur within wireless communication systems. For instance, handoffs may be mobile-directed such that upon detecting a signal with a signal quality (e.g., signal to noise ratio (SNR)) above a threshold from a disparate sector differing from a sector to which the wireless terminal is currently connected, the wireless terminal may attempt to access the disparate sector. Oftentimes, make before break handoffs may be utilized such that a link to the current sector may be broken prior to accessing the disparate, detected sector. Further, access to a sector may be contention-based where two or more wireless terminals may transmit access requests to the sector at a substantially similar time over a shared resource (e.g., channel); thus, by employing contention-based techniques, handoffs within typical wireless communication systems may encounter significant time delays. Moreover, wireless terminals that perform conventional handoffs within a multicarrier setting where different sectors may be associated with disparate carriers may probe for other sectors and/or carriers for handing off to by way of retuning, which may cause loss of a current connection.