This invention provides a charging member exhibiting high electrical charge injection efficiency.

1. Field of the Invention
The present invention relates to a charging member and an electrophotographic image forming apparatus.
2. Description of the Related Art
In the charging mechanism (charging principle) of contact charging, two kinds of charging mechanisms of (1) discharge charging mechanism and (2) direct injection charging mechanism are mixed, and the characteristics of a more dominant mechanism thereof appear.
According to the direct injection charging mechanism, charges are directly injected from a contact charging member to a body to be charged, whereby the surface of the body to be charged is charged. A charging apparatus employing a charging brush as the contact charging member is simple in terms of mechanism and is more advantageous in terms of cost than a roller charging method employing a charging roller. Therefore, the charging apparatus is being put into practical use.
However, according to the charging method including performing contact injection charging, sufficient properties in terms of injection efficiency and the like are still difficult to obtain.
In charging with a charging brush, the brush hair of the charging brush needs to be brought into uniform contact with the surface of a photosensitive member. Therefore, as fibers constituting the brush hair, electro conductive fibers in which an electro conductive filler, such as carbon, is dispersed in a base resin, such as Nylon-6, Nylon-66, Nylon-12, polyethylene terephthalate, polyethylene, and polypropylene, are used.
The electro conductive fiber is manufactured by kneading and melting resin compound pellets containing a base resin and an electro conductive filler with a desired ratio in, for example, an extruder, extruding the molten substance from a nozzle plate, and then cooling and drawing the same.
The surface of the electro conductive fiber manufactured by the above-described method almost contains an electrically insulating base resin.
Therefore, when it is attempted to charge a photosensitive member using a charging brush having the brush hair containing such electro conductive fibers, injection of charges from the charging brush to the photosensitive member is performed only when the electro conductive filler exposed to the surface of the electro conductive fiber directly contacts the photosensitive member. Therefore, there has been a problem in that the charging efficiency has been poor.
Japanese Patent No. 4089122 discloses increasing the electrical charge injection rate in a charging member which charges the surface of a body to be charged by mechanically polishing and/or cutting an electro conductive resin molded product to project a part in the longitudinal direction of a carbon nanotube out of the electro conductive resin molded product.
Moreover, Japanese Patent Laid-Open No. 2007-34196 discloses that, by the use of electro conductive fibers in which carbon nanotubes as an electro conductive filler dispersed in a base resin are almost oriented to the longitudinal direction of the fiber, a variation in the electrical resistance values of the electro conductive fibers can be reduced in a charging member for an image forming apparatus.
Moreover, Japanese Patent Laid-Open No. 2008-138304 discloses that, in order to remove a skin layer on the surface of an electro conductive fiber in which carbon nanofibers are dispersed in a polyester resin, the electro conductive fiber is immersed in an aqueous alkaline solution to perform etching treatment of dissolving a resin portion of the fiber surface to thereby reduce the contact resistance of the electro conductive fiber surface.
However, under the injection charging conditions of an increase in speed or an increase in image quality desired in an image forming apparatus, it cannot be expected to give a sufficient charging voltage to the surface of a photosensitive member for reasons described later.
In the charging member disclosed in Japanese Patent No. 4089122, all or some of the carbon nanotubes project from the charging member surface, and therefore, when charges are injected to a photosensitive member, charge are injected only from the tip portion of the carbon nanotubes directly contacting the photosensitive member. Therefore, highly efficient electrical charge injection cannot be expected.
In the electro conductive fiber disclosed in Japanese Patent Laid-Open No. 2007-34196, the direction of the carbon nanotubes dispersed in the base resin are almost uniform in the length direction of the fiber in the base resin. Therefore, when charges are injected to a photosensitive member, a skin layer having electrically high resistance present on the surface of the electro conductive fiber contacts the photosensitive member. Therefore, the injection of charges from the side surface of the electro conductive fiber is not almost performed, so that highly efficient electrical charge injection cannot be expected.
In the electro conductive fiber disclosed in Japanese Patent Laid-Open No. 2008-138304, the skin layer on the fiber surface is removed by chemical etching treatment. However, carbon nanofibers as an electro conductive filler are uniformly arranged in the length direction of the fiber in the polyester resin manufactured by melt spinning method, and therefore when charges are injected to a photosensitive member, charges are injected to the surface of the photosensitive member only in a portion of the carbon nanofibers present on the surface at the side surface of the electro conductive fiber, so that highly efficient electrical charge injection cannot be expected. Furthermore, the chemical etching treatment can be substantially performed only to polyester as a base resin, and is difficult to apply to another resin.

Charging member and electrophotographic image forming apparatus

Abstract: The charging member has an electro conductive base and an electro conductive fiber, one end of which is connected to the base, in which the fiber contains a plurality of carbon nanotubes which are entangled, and the carbon nanotubes are exposed at the tip portion of the fiber.


A sort buffer includes a phase sector determination circuit, a phase sector update circuit, and a phase sector completion circuit. The phase sector determination circuit is configured to determine a phase sector corresponding to a phase of a first sine and cosine sample pair received from an encoder or resolver. The phase sector update circuit is configured to determine whether a second sine and cosine sample pair corresponding to the phase sector is stored in a lookup table (LUT) and, in response to a determination that a second sine and cosine sample pair corresponding to the phase sector is not stored in the LUT, store the first sine and cosine sample pair in the LUT. The phase sector completion circuit is configured to determine whether the LUT has stored, for each of a plurality of phase sectors, a corresponding sine and cosine sample pair.

Position detectors, such as encoders and resolvers, may be utilized to determine the angular position of an electric motor. Sine and cosine incremental angle encoders and/or resolvers encode the angular position of the motor into two quadrature modulated sine and cosine signals. The number of sinusoidal periods per revolution depends on the encoder line count and is typically in the range of 50 to 5000 for an encoder and one period per revolution for a resolver. Sine and cosine incremental encoders and/or resolvers allow high-resolution angle determination due to interpolation. More particularly, the high-resolution angle is typically calculated using the arctangent of the ratio between the sine signal and the cosine signal.

Motor drive phase sector buffer, offset and gain error circuitry


A digitizer with increased dynamic range is provided by applying varying gains/attenuations to an input signal and feeding the resulting scaled signals to several conventional analog-to-digital converters to be digitized. The digitized version of the largest scaled signal which does not result in its respective analog-to-digital converter from saturating is selected by a multiplexer to be fed through as the digitizer output. Each of the gains(attenuations) differ by multiples of approximately 6 dB, since one bit in an ADC represents this value. The multiplexer outputs a digital sample size which is larger than that of the analog-to-digital converters and with the selected digitized version being output as the appropriate subset of the larger sample size to account for the gain(attenuation) of the selected signal. Preferably, this is used in a wideband receiver to increase the dynamic range of the receiver.

It is a problem with existing wideband radios in basestations that they include ADCs (analog-to-digital converters) which do not have sufficient dynamic range to simultaneously handle properly the large signal strengths from mobiles which are close to the basestation and the small signal strengths from mobiles which are far from the basestation close to the basestation's cell boundary. Typically, when the signal strength becomes too large, the ADC saturates, and outputs a digital signal which contains no useful information.
Some existing systems attempt to overcome this problem through the use of AGC (automatic gain control) in which a variable attenuator is used to insert a variable loss in the analog signal before it is digitized. Due to the dynamic range required and the lower frequency limit of PIN diode switches, AGC cannot be implemented at baseband, and implementing the AGC at RF (radio frequency) would degrade the noise figure of the receiver unduly. A compromise solution involves using the AGC at the IF (intermediate frequency). Such a solution has at least three problems. Firstly, a significant noise figure degradation results due to the limited amount of gain in front of the variable attenuator. Adding more gain in front of the attenuator is not feasible due to the linearity constraint of subsequent components. Secondly, the overload is easiest detected at the digital side of the ADC. By the time the overload is detected, a finite amount of signal is lost due to ADC overload, and clicks are detected at audio. In addition, data is lost in CDPD (cellular digital packet data) and modem applications. Thirdly, the circuit implementation is complex and costly.
In U.S. Pat. No.5,422,643 which issued Jun. 6, 1995 to Chu et al., an ADC with expanded dynamic range is proposed wherein the analog signal is duplicated in a plurality of channels each with a different attenuation or gain inserted. Then, depending upon the amplitude of the signal, a particular channel is chosen such that the resulting compensated signal will not saturate the ADC but will be close to full scale of the ADC. At the output of the ADC, the digitized signal must be adjusted to reflect the attenuation or gain inserted. The circuitry for selecting the particular analog channel is complex and requires complicated calibration procedures. Furthermore, there is no suggestion in Chu et al. that this type of ADC would be appropriate for use in a wideband receiver context.

Dynamic range extension of wideband receiver


A pharmaceutical composition with an immunomodulating function is provided, including an extract of Bupleurum obtained by grinding the Bupleurum, adding the ground Bupleurum to a solvent and isolating the extract from the solvent, wherein the Bupleurum comprises Bupleurum krlovianum, Bupleurum longiradiatum, Bupleurum smithii, Bupleurum pusillum, Bupleurum longicaule, Bupleurum salicifolium, Bupleurum scorzonerifolium and Bupleurums with at least one of the nucleotide sequences selected from a group consisting of SEQ ID NOs. 1˜6 and a nucleotide sequence with no more than 1% of the nucleotide sequence divergences of SEQ ID NOs. 1˜6, or combinations thereof.

1. Technical Field
The disclosed relates to a pharmaceutical composition with an immunomodulating function, and in particular relates to an extract of Bupleurum with an immunomodulating function.
2. Description of the Related Art
The mechanism for immune disorders has been reported in several studies. Many studies indicate that the over-expressed tumor necrosis factor (TNF-α) is related to immuno-inflammatory diseases, such as rheumatoid arthritis (RA), Crohn's disease, psoriatic arthritis or ankylosing spondylitis.
TNF-α functions like cytokines, modulates cell recruitment, cell proliferation, cell death and immune regulation. At low concentrations in tissues, TNF-α may augment host defense mechanisms against infection. At high concentrations, TNF-α results in excess inflammation leading to organ injuries. Thus, Brennan et al. reported that the removal of excess TNF from the sites of inflammation can treat the immune disorders caused by inflammatory responses (Brennan et al., 1989, Inhibitory effect of TNF-α antibodies on synovial cell interleukin-1 production in rheumatoid arthritis. Lancet 2, 244-247).
Feldmann et al. reported that TNF plays a particularly important role in the regulation of a cascade of pathogenic events in RA, Crohn's disease, psoriasis and other diseases, exemplified by the rapid induction of cytokines, such as IL-1β and IL-6 (Feldmann et al., 2002, Discovery of TNF-α as a therapeutic target in rheumatoid arthritis: preclinical and clinical studies. Joint Bone Spine 69, 12-18). TNF is over-expressed particularly in animal models of RA (Keffer et al., 1991, Transgenic mice expressing human tumor necrosis factor: a predictive genetic model of arthritis. EMBO J 10, 4025-4031). It has been suggested that a dramatic reduction in serum IL-6 concentrations occurred within 1 day of infliximab therapy was a direct effect of TNF neutralization (Charles et al., 1999, Regulation of cytokines, cytokine inhibitors, and acute-phase proteins following anti-TNF-α therapy in rheumatoid arthritis. J Immunol 163, 1521-1528).
Many biologics with inhibition of TNF-α have been produced, such as adalimumab, etanercept, infliximab, DMARDs (for example, methotrexate), or NSAIDs. Due to fast drug efficacy, dramatic effects and well immune toleration, these biologics have become main stream market products. However, biologics are expensive, demanding intravenous administration and have adverse effects, such as risks of inducing undesired immune responses or infection. Developing a drug which is safe for the immune system is challenging.
Bupleurum is a genus of plants used in Chinese medicine for reducing fever, relieving pain, eliminating toxins and reducing inflammation. In Chinese medicine, Bupleurum primarily treats fullness and discomfort in the chest, bitterness in the mouth, dryness in the throat, alternate spell of chill and fever, jaundice, hepatitis, enterogastritis and cholecystitis. The root of Bupleurum is usually used. It has been reported that saikosaponin, longispinogenin, sterols, lipid oil, isoflavones and sugars were isolated from the root of a plant of Bupleurum, and saikosaponin was determined as the chief component. Saikosaponin a and d have been proved to have medicinal effects (Liu S. U., et al., Development Diversity of Bupleurum, Journal of Agricultural Research of China, v. 53, No. 2 (June, 2004)).
Bupleurum has been enthusiastically studied for hepatitis. However, there is no study or journal published implementing the application of Bupleurum to immunomodulation. The inventors have studied the extraction of Bupleurum, wherein the active ingredient of the extract was identified, and the relationship between the active ingredient and TNF-α or IL-6 in vivo was determined. Finally, a novel pharmaceutical composition with an immunomodulation has been developed.

Pharmaceutical composition with immunomodulating function

Industrial Technology Research Institute


Bacillus licheniformis O.W.U. 138B and 88B and other bacterial strains capable of degrading feathers isolated from wild birds, are disclosed. The strains and the keratinases produced by these strains are useful for degrading waste feathers produced by commercial poultry processing; producing animal feed, fertilizer, or natural gas from poultry waste; and cleaning of certain fabrics.

Keratins are a major class of structural proteins that are highly resistant to biological degradation. Common enzymes which break down protein, such as trypsin, do not affect keratin. Keratins are insoluble in water. Keratins, like other proteins, are made of a long string of various amino acids, which fold into a final 3-dimensional form. Alpha helix and beta sheet are common parts of such a 3-dimensional form. Long, thin biological structures often contain alpha helixes, while flat structures are often built from beta sheets. Some keratins are rich in alpha helix structures, while others are mostly beta sheet. These two major types of keratin are known as alpha-keratin and beta-keratin. Wool and hair are largely composed of alpha-keratin. Feathers are largely composed of beta-keratin.
The poultry processing industry produces huge quantities of turkey and chicken feathers as a by-product. These feathers constitute a sizable waste disposal problem. Several different approaches have been used for disposing of feather waste, including landfilling, burning, natural gas production, and treatment for animal feed. Most feather waste in the United States is landfilled or burned, which involves expense and can cause contamination of air, soil and water.
Natural gas production from waste materials is rarely used in the U.S., due to the low price of U.S. natural gas and the availability of land for landfilling. Thermophilic anaerobic poultry waste digestors are known which can produce significant amounts of natural gas from poultry manure and other waste. Bacteria are combined in these digestors with the poultry waste, fermented, and the natural gas produced is collected. The effluent remaining after fermentation can be used as animal feed or fertilizer.
Animal feed typically includes a carbohydrate source and a protein source. The protein source provides needed amino acids to the animal. Common protein sources used in animal feed include soy meal; fish meal; blood meal; meat or poultry by-products; and meat and poultry meal. These protein sources are generally expensive. Feather waste is high in protein and very inexpensive, but cannot be used directly in animal feed, as it is difficult for animals to digest. A small percentage of feather waste is steamed, chemically treated, ground, or some combination of these to form feather meal. Feather meal is used as a dietary protein supplement for animals. Typical treatments to form feather meal are expensive. These treatments also tend to destroy some amino acids, such as heat-sensitive amino acids when steam treatment is used. This lowers the quality of the protein in the feed. Due to these problems, feather meal is not extensively used in feed, despite the expense of other sources of dietary protein.
Bacterial strains are known which are capable of degrading feathers. These bacterial strains produce enzymes which selectively degrade the beta-keratin found in feathers. These enzymes make it possible for the bacteria to obtain carbon, sulfur, and energy for their growth and maintenance from the degradation of beta-keratin. An enzyme capable of degrading protein is known as a protease, and is described as having proteolytic activity. An enzyme which degrades keratin is a keratinase, while a beta-keratinase is an enzyme capable of degrading beta-keratin. An enzyme which degrades keratin can also be described as having keratinolytic activity. The same enzyme can be referred to as a protease, a keratinase, and a beta-keratinase if it has all three properties.
Prior feather-degrading bacterial strains, such as Bacillus licheniformis PWD-1 (ATCC 53757), have been isolated from chicken waste and poultry waste digestors. See generally Williams, C. M. et al, Isolation, Identification, and Characterization of a Feather-Degrading Bacterium, Applied and Environmental Microbiology, Vol. 56, No. 6, June 1990, pp. 1509-1515. Specific primers, probes, and polymerase chain reaction (PCR) techniques for the keratinase gene of B. licheniformis PWD-1 are known. Keratinolytic microorganisms have been found in soil and agricultural compost. U.S. Pat. Nos. 5,063,161 and 4,959,311 describe methods of degrading keratinaceous material and bacteria useful for such degradation. U.S. Pat. No. 5,171,682 describes a purified B. licheniformis PWD-1 keratinase capable of degrading feathers. U.S. Pat. No. 5,186,961 describes a method and composition for maintaining animals on a keratin-containing diet. U.S. Pat. No. 4,908,220 describes a hydrolyzed feather feed ingredient (feather-lysate) and animal feeds containing feather-lysate.
Large numbers of dead, unsaleable birds are another waste product produced by commercial poultry processing. Since the feathers are resistant to degradation, the feathers often remain after the soft parts of a dead bird have decomposed. Other wastes from poultry processing, such as poultry manure, often contain significant amounts of difficult-to-degrade feathers. The feathers in these waste products make disposal more difficult and expensive.
Proteins make up many common stains that are found on clothing. When the proteins involved are insoluble in water, the stain is often difficult to remove. Blood stains are an example. Addition of enzymes capable of degrading proteins to detergents for cleaning clothes is well known in the art, U.S. Pat. No. 5,079,154. Since keratin is a protein which is insoluble in water, enzymes with keratin-degrading activity are known to be effective detergent additives.
B. licheniformis is a rod-shaped, endospore-forming bacteria. The rods are often in chains. Colonies on agar are opaque with dull to rough surface. Wrinkled outgrowths are common. The colonies are usually attached strongly to the agar, and mounds and lobes consisting largely of slime often accumulate on the colony, especially on glucose agar or glutamate-glyceral agar. Glutamyl polypeptide is formed as an extracellular amorphous slime. Levan is produced extracellularly from sucrose and raffinose. Red pigment is formed by many strains on carbohydrate media containing sufficient iron Aged cultures may become brown. Freshly isolated strains grow with ammonia as the sole source of nitrogen in the absence of growth factors. Spores are known to occur in soil. Many spores survive severe heat treatment. Refer generally to Bergey's Manual of Systematic Bacteriology, Vol. 2, Section 13, P.H.A. Sneath, ed., Williams & Wilkins, L.A.


A method, digital video display and digital video recording (DVR) device/system and computer program provide a mechanism for controlling an amount of differing types of media viewed by users. A number of time quotas are set for various media types and/or programs and viewing or recording of video media is monitored to determine whether any of the quotas has been exceeded. If a quota is exceeded, the viewing or recording can be immediately halted, or a warning or alert can be issued. If an absolute limit is exceeded after an alert is issue, further viewing or recording can be halted.

1. Field of the Invention
The present invention is related to consumer digital video display and digital video recording devices (DVRs), and more particularly to a method and system that manage viewing, recording and/or playback of video content according to quotas for different genres.
2. Description of Related Art
Digital video recorder (DVRs), which may be in the form of a portable device such as a personal video recorder (PVR), a set-top box or a computer having a video interface and/or video capability provided from a digital or analog network source are becoming ubiquitous in households and other locations. Further, present-day monitors and televisions provide a greater degree of programmable control than has been available in the past.
For the purposes of parental control/monitoring, parental controls have been implemented that block the viewing and/or recording of video material that carries an indication that the material may be unsuitable for children below a specified age. Such controls have been extended to digital media that carries rating information or title information that permits determining whether media may be unsuitable for viewing by some viewers and therefore requires a personal identification number (PIN) or other token to provide access.
However, even permissible media, when viewed in excess, may be undesirable. Depending on what the particular media is being viewed by a child or younger adult, parents, educational institutions and others may desire to promote certain content over other content or restrict the amount of less-desirable content that is displayed or recorded by such users.
Therefore, it would be desirable to provide a method and system that can provide control of video viewing or recording that is adaptable to the desirability of content of the media being viewed or recorded by a particular user or class of users, such as an age group of children.

International Business Machines Corporation


A system and an article of manufacture for de-duplicating virtual machine image accesses include identifying one or more identical blocks in two or more images in a virtual machine image repository, generating a block map for mapping different blocks with identical content into a same block, deploying a virtual machine image by reconstituting an image from the block map and fetching any unique blocks remotely on-demand, and de-duplicating virtual machine image accesses by storing the deployed virtual machine image in a local disk cache.

Challenges exist in the de-duplication of virtual machine (VM) images. Input/output (I/O) contention occurs when accessing VM images, and managing such contention can be important for application performance, user experience, infrastructure cost, etc. However, challenges can arise due to, for example, a high density virtualized environment, a large number of VM images, and/or limited resources (memory and disk space) for caching images locally on compute nodes.
Different VM images often have common portions of data. Reasons for similarity can include, for example, similar operating systems, similar applications, and/or the fact that many new images are created by slightly modifying existing images. Accordingly, VM image access de-duplication aims to avoid I/O operations on blocks with identical content.
Existing approaches include on-demand streaming of a VM image, which includes copy-on-read (CoR), copy-on-write (CoW), and adaptive pre-fetching. Such approaches, however, do not exploit image similarity. Existing approaches can also include the use of a de-duplicated VM image repository. Such approaches attempt to exploit image similarity to combat image sprawl, but lack run-time support (that is, retrieving an image requires reconstituting and copying the entire image).
Other approaches include a general de-duplicated file system, which attempts to exploit file content similarity to reduce disk space occupation, but requires replacing existing file systems. Also, such approaches only consider de-duplicating block allocation instead of file access. Additionally, existing approaches can include VM memory page/cache sharing. Such approaches attempt to discover and share identical memory pages by content scanning or exchanging page information, but introduce high overhead costs.

This patent is subject to a terminal disclaimer.

Virtual machine image access de-duplication


A method and apparatus for improving the signal-to-noise ratio (SNR) and dynamic range of an optical fiber system. An optical fiber system (10) includes a laser(12) that produces a coherent light signal conveyed over an optical fiber (14) to a Mach-Zehnder modulator (16). An input signal modulates the coherent light, producing modulated side bands, which together with the carrier comprise a modulated light signal. The modulated light signal is filtered using an integrated optical filter (24) that substantially attenuates the carrier frequency, while passing light at the frequency of the modulated side bands. A detector (28) demodulates the filtered light with a substantially greater SNR than would otherwise have been possible. In one preferred form of the invention, the integrated optical filter comprises an imbalanced interferometer (40), and in another embodiment, tile interferometer produces imperfect nulls aligned with the carrier frequency. A relatively higher power laser(12) can be used without damage to detector (28), since the integrated optical filter substantially reduces the average power of the modulated light by attenuating the carrier, thereby enhancing SNR and dynamic range of the system.

There are numerous applications in which it is preferable to transmit an analog or digital signal over an optical fiber instead of through an electrically conductive cable. An optical fiber offers several inherent advantages over a copper conductor, such as lighter weight and resistance to electromagnetic interference. In recent years, the cost of optical fiber systems has dramatically decreased, while their efficiency has proportionally improved, with losses typically less than 0.1 dB/km. Components, including diode-pumped lasers, modulators, and detectors are readily available from commercial sources to construct a system that can produce coherent light, modulate the light with an analog or digital signal, and convey the modulated signal some distance to a remote detector for demodulation to recover the signal.
However, the transmission of signals over optical fibers is not without its problems. For example, noise on a signal transmission system can significantly impact its ability to convey low amplitude signals developed by radio frequency (RF) remote antenna sources, due to the small optical modulation depth such signals typically develop. Noise affecting a modulated signal in a fiber optic system typically comprises three types, including thermal, shot, and intensity noise, any one or more of which can substantially degrade the system's signal-to-noise ratio (SNR). Aside from noise, several other problems with optical fibers systems have become more evident as low noise diode-pumped solid-state laser sources of increasing power have been developed. Although the higher power provided by such devices can help to improve the SNR signal distortion resulting from harmonic generation in the detector used to demodulate the light signal is a potential source of degraded performance in the system and potentially represents the primary disadvantage of higher power light sources. The problem arises because the higher power light produced by such sources develop high levels of photogenerated charge in the detector, which shield the electric fields comprising the optical signal from the applied bias voltage. If the light signal applied to the detector is sinusoidally modulated, shielding of the electric fields in the detector produces harmonics that distort its output signal.
Thermal damage to detectors can also occur when the power produced by the light source is sufficient to cause over heating. If high frequency photodetectors are required for a particular application, their size must be kept small to limit the effects of capacitance. However, a smaller photodetector is more susceptible to damaging thermal heating caused by receiving an optical signal from a high power laser source.
Higher power laser sources also tend to be more limited by Brillouin scattering, since this characteristic, which is associated with the propagation of an optical signal, increases exponentially with the product of optical power and the length of the optical fiber. Brillouin scattering is due to a coupling between acoustic waves in the optical fiber and the electromagnetic field associated with the optical signal; the scattered light produced by this effect propagates in the opposite direction from that of the optical signal. Since noise initiates the Brillouin scattering process, the SNR is deleteriously affected. Reducing the optical power minimizes the scattering process, but also reduces the SNR.
The conventional method for improving the SNR of an optically modulated signal is to increase the optical power of the signal or to increase the degree of modulation. For certain applications, it is not possible to increase the modulation depth, because the drive signal to the optical modulator is very weak, or because a higher modulation signal would drive the modulator into a non-linear region. The alternative is then to use higher power laser sources; yet, as noted above, increases in optical power are limited by the onset of signal distortion caused by harmonic generation in the detector, Brillouin scattering, or by the maximum photodetector current that might damage the detector. Thus, even though higher optical power sources are more readily available, the power of such sources is not usable in conventional systems. Accordingly, it is evident that there is a need for a new method of handling modulated light signals and for a system that uses higher powered optical sources to convey weak modulation depth signals at acceptable SNR levels not limited by detector distortion, possible detector damage, or Brillouin scattering.

Optical carrier filtering for signal/noise and dynamic range improvement


An improved folder includes a first series of belts which grips and moves sheet material along converging deflectors to fold the sheet material. As the space between the deflectors narrows, a second series of belts grips the sheet material and continues its movement between the deflectors. The first series of belts includes a first plurality of tapes disposed on a first side of a fold line and a second plurality of tapes disposed on a second side of the fold line. The second series of belts includes a pair of creaser belts which extend from between the tapes to an outlet portion of the folder. The speed of movement of the tapes and creaser belts is coordinated by using speed signal generators which are driven at the speed of movement of the tapes and creaser belts. A controller compares the speed signals and maintains a desired relationship between the speed of movement of the tapes and creaser belts. It is believed that the creaser belts will usually be driven at the same speed. However, the creaser belts may be driven at slightly different speeds in order to compensate for deformation imparted to the sheet material before it moved between the creaser belts.

The present invention relates to a new and improved sheet material handling apparatus in which the speed of movement of a plurality of belts is coordinated to prevent unintended deformation of the sheet material.
A sheet material folding apparatus is disclosed in a copending U.S. Pat. application filed by Richard E. Breton and David B. Staley and entitled "Folder Apparatus". This application discloses a folder apparatus which is operable at a relatively high speed to form a plurality of folds in sheet material. The folds are formed by a series of folder assemblies through which the sheet material continuously moves at a relatively high speed. The folded sheet material is stacked on edge by a stacker assembly.
One of the folder assemblies includes a tapered array of belts which move the sheet material to be folded into the folder assembly. As the sheet material is moved by the tapered array belts,, it is engaged by a pair of creaser belts. The creaser belts grip opposites sides of the sheet material and move the sheet material out of the folder assembly.
During operation of this folder assembly, the speed of movement of the sheet material by the tapered array of belts and by the creaser belts must be accurately coordinated so that the sheet material can be gripped by the creaser belts while it is being moved by the tapered array of belts. Once the sheet material has been gripped by the creaser belts, the speed of movement of the upper and lower creaser belts must be accurately coordinated in order to prevent unintended deformation of the sheet material. Thus, if one of the creaser belts is moving faster than the other creaser belt, one side of the sheet material will be pulled forwardly relative to the other side of the sheet material.
Difficulties are encountered in coordinating the speed of movement of the creaser belts. This is because, the effective pitch diameters of the pulleys or sheaves which support and drive the creaser belts varies during operation of the folder. Variations in the effective pitch diameters of the creaser belt pulleys are due to several different factors. Included among these factors are: (1) the V-shaped configuration of cooperating surfaces on the pulleys and the creaser belts and (2) variations in the cross-sectional size of the creaser belts along the length of the creaser belt.
The creaser belt pulleys are of the well known V-type. A slight change in the spacing between the side surfaces of a creaser belt which engages a pulley results in a larger change in the pitch diameter of the pulley. Thus, if the distance between the side surfaces of a creaser belt decreases slightly, the creaser belt will move a larger distance inwardly toward the center of rotation of the pulley which it engages. Similarly, if the distance between the side surfaces of the creaser belt increases, the creaser belt will move a larger distance outwardly away from the center of rotation of the pulley. Therefore, the cooperation between the creaser belts and pulleys effectively magnifies any change in the cross section of the creaser belts.
The creaser belts may be commercially fabricated by an extrusion process. During extrusion of a creaser belt, it is extremely difficult to hold very close tolerances on the cross sectional size of the creaser belt. Therefore, the cross section of the creaser belt, as originally formed, varies along the length of the belt. During use, the creaser belt will tend to stretch due to tension on the belt and centrifugal effects. Of course, stretching of the creaser belt will change the cross sectional size of the belt.
The foregoing and other factors make it very difficult to maintain the effective pitch diameter of the pulleys around which the creaser belts extend constant during movement of the belts. Of course, if the effective diameter of the pulleys which engage the creaser belts vary during movement of the belts, the speed of movement of the creaser belts will vary. When the speeds of creaser belts vary, one of the belts will move further than the other belt. Thus, in a test, one creaser belt of a pair of creaser belts moved 1.25 inches further than the other belt in four feet of belt travel. Of course, if creaser belts engaging opposite sides of a signature travel through different distances, the signature will be deformed by the creaser belts.


A surgical instrument is provided that includes a first input mechanism having axial slots formed in a periphery and a second input mechanism having helical slots formed in a surface. The instrument also includes an insert having pins extending from a surface thereof, the insert coupled to the second input mechanism such that the one or more pins extend into the helical slots, and a surgical device coupled to an end. The surgical device is moved in a first degree of freedom in response to a mechanical driving force applied to both the first input mechanism and the second input mechanism, respectively, and the surgical device is moved in a second degree of freedom in response to a mechanical driving force applied to the second input mechanism while the first input mechanism is held stationary.

1. Technical Field
The present disclosure is related to a minimally invasive surgical instrument. In particular, the present disclosure is related to a minimally invasive surgical instrument for providing needle-based therapy including ablation therapy.
2. Discussion of Related Art
Minimally invasive surgery is known under various names (e.g., endoscopy, laparoscopy, arthroscopy, endovascular, keyhole, etc.), often specific to the anatomical area in which work is done. Such surgery includes the use of both hand-held and teleoperated/telemanipulated/telepresence (robot assisted/telerobotics) equipment, such as the da Vinci® Surgical System commercialized by Intuitive Surgical, Inc. of Sunnyvale, Calif. Both diagnostic (e.g., biopsy) and therapeutic procedures may be performed using such robot assisted equipment. Instruments may be inserted into a patient percutaneously via surgical incision or via natural orifice. Although teleoperative surgery using the da Vinci® Surgical System provides great benefits over, for instance, many hand-held procedures, for some patients and for some anatomical areas the da Vinci® Surgical System is unable to effectively access a surgical site. For example, the da Vinci® Surgical System may be inadequate for performing certain types of surgeries and therapies, including needle-based surgeries and percutaneous procedures such as prostate focal therapy.
Prostate cancer is among the most common noncutaneous cancers in American men. There are two common screening methods for prostrate cancer, namely the prostate-specific antigen test (PSA) and the digital rectal exam (DRE). The PSA test, which determines a likelihood of prostate cancer from antigen concentrations in the blood sample, is not conclusive. In the DRE, the physician can determine whether the prostate gland is enlarged or there are abnormal nodules present. In either case, needle biopsies are often recommended to determine if tumors exist and whether or not any tumor is benign or malignant. Each year 1.5 million core needle biopsies are performed, yielding several hundred thousand new cases of prostate cancer. In many cases, early detection of the cancer results in higher efficacy of the treatment methods utilized. Further, MRI-guided needle based therapies (biopsies, localized laser ablations, delivery of implantable seeds utilized in low-dose-rate (LDR) permanent brachytherapy, which is a common treatment for prostrate cancer, or other treatment) have been demonstrated to be successful. However, manipulation of the needle in the confined space afforded by the typical MRI instrument has proven challenging.
What is needed is a minimally invasive surgical instrument that can be used to perform image guided needle-based therapies and surgeries.

Minimally invasive surgical instrument to provide needle-based therapy


The aromatic heterocyclic copolymer is produced by (a) reacting (i) an aromatic diaminodithiol compound, hydrogen atoms of thiol groups of which compound are substituted with substituted or unsubstituted alkyl groups, with (ii) an aromatic diamino compound and (iii) a dicarboxylic acid derivative in an organic solvent, to produce a precopolymer; and (b) heating the precopolymer to cause a thiazole ring closure reaction. This aromatic heterocyclic copolymer is contained as a reinforcing polymer in a molecular composite material.

The present invention relates to a method of producing an aromatic heterocyclic copolymer having excellent heat resistance, mechanical properties, chemical resistance, electric properties, etc., and to a method of producing a molecular composite material comprising such an aromatic heterocyclic copolymer and a matrix polymer suitable as a structural material for aircrafts, automobiles, spacecrafts, etc.
Recently, to achieve the reduction of weight of aircrafts, automobiles, etc., plastic materials called "engineering plastics" having excellent mechanical properties, heat resistance, etc. have been increasingly used. Apart from this, development has been actively carried out to provide composite materials such as FRPs consisting of plastic materials and high-strength, high-modulus fibers such as carbon fibers, and these composite materials are being used in many applications.
It is known that the strength of these composite materials largely depend not only on the strength of plastics and reinforcing fibers but also on the interfacial bonding strength of the fibers to the matrix resins. Also, the impregnating capability of matrix resins into the fiber-reinforced preforms affect the easiness of production of composite materials and the strength of the resulting products. Accordingly, the use of high-strength, high-modulus fibers and resins would not necessarily result in composite materials having excellent strength.
Under such circumstances, to overcome the above problems, proposals have been made to develop high-strength polymer blend composites (molecular composite materials) by finely dispersing rigid polymers such as aromatic polyamides, etc. in matrix resins to a molecular level.
Aromatic polymers suitable for molecular composite materials include those containing heterocyclic repeating units such as thiazole rings, imidazole rings, oxazole rings, etc. Among them, an aromatic polythiazole having a thiazole ring is highly promising because of its excellent mechanical strength.
In the meantime, the homogeneous dispersion of a reinforcing polymer such as an aromatic polythiazole in a matrix polymer cannot be achieved if the reinforcing polymer is simply blended with the matrix polymer, because of the rigidity of the reinforcing polymer which makes it less compatible with the matrix polymer. This means that simple blending fails to provide a molecular composite material having excellent mechanical properties. Therefore, various attempts have been made so far.
For instance, Japanese Patent Laid-Open No. 1-287167 discloses a method of producing a polymer composite comprising the steps of introducing a polymer solution mainly containing (A) a reinforcing polymer consisting of polythiazole having a substantially rod-shaped skeleton and (B) a matrix polymer fusable with the reinforcing polymer into a solidification bath, and forming it into a film, the above polymer solution showing an optical anisotropy and being solidified via a phase apparently having an optical isotropy, after immersion in the solidification bath.
Japanese Patent Publication No. 2-7976 discloses a polymer composition comprising a reinforcing polymer A consisting of polythiazole having a substantially rod-shaped skeleton, and a matrix polymer B consisting of a less-crystallizable aromatic copolyamide having a glass transition temperature of 200.degree. C. or higher and a flow-initiation temperature of 500.degree. C. or lower, a weight ratio of A/(A+B) being 0.15-0.70. When the aromatic copolyamide is kept at a temperature between its glass transition temperature and its flow-initiation temperature for an arbitrary period of time within 5 hours, the resulting crystals have apparent sizes of 25 .ANG. or less.
However, in the methods of producing polymer composites as disclosed in Japanese Patent Laid-Open No. 1-287167 and Japanese Patent Publication No. 2-7976, homogeneous dispersions of the reinforcing polymers in matrix polymers are not expected. This means that the resulting molecular composite materials do not show largely improved mechanical strength, etc. This appears to be due to the fact that the rigid reinforcing polymers and the matrix polymers do not show good compatibility with each other.
Thus, proposals have been made to provide a method of producing a molecular composite material of a rigid aromatic polymer without resorting to direct mixing of the rigid aromatic polymer and a matrix polymer, the method comprising the steps of homogeneously mixing a prepolymer of the rigid aromatic polymer and a matrix polymer or its prepolymer in an organic solvent, removing the organic solvent and then heating it so that the rigid aromatic polymer is formed from its prepolymer in the molecular composite material (Japanese Patent Laid-Open Nos. 64-1760 and 64-1761). By the above methods, molecular composite materials having relatively good mechanical strength, etc. can be produced.
However, the inventors have noticed that when thermal compression moldings of these molecular composite materials are produced from the aromatic polythiazole prepolymers and thermoplastic resins as matrix polymers by the methods of Japanese Patent Laid-Open Nos. 64-1760 and 64-1761, part of thiol groups in the prepolymers is subjected to a thiazole ring-closure reaction in the process of thermal forming of homogeneous mixtures of the aromatic polythiazole prepolymers and the matrix polymers, and that the resulting molecular composite materials show poor mechanical properties.
With respect to the rigid aromatic polymers, polymers having in their repeating units heterocyclic rings such as a thiazole ring, an imidazole ring, an oxazole ring, an oxazinone ring, etc. have been attracting much attention as high-strength, high-modulus, high-heat resistance polymers with high rigidity.
Among them, an aromatic polythiazole having a thiazole ring can be expected to show good properties as a plastic substitute for metal materials when used alone or in combination with other engineering plastics.
However, the rigid aromatic polymer such as the aromatic polythiazole generally has a poor solubility in organic solvents, etc. due to its high rigidity, and it is soluble only in limited kinds of strong acids such as metasulfonic acid, chlorosulfonic acid, etc. Also, it has only poor elongation and flexibility, meaning that it is poor in moldability. Accordingly, it is difficult to mold the rigid aromatic polymer without mixing with other materials.
Also, even in the case of forming a composite material of the rigid aromatic polymer and a matrix polymer, the above problem of poor moldability still remains. Further, since the rigid aromatic polymer does not show a good compatibility with the matrix polymer, it is difficult to blend the rigid aromatic polymer with the matrix polymer at a desired proportion.
To overcome such problems, it is possible to introduce a flexible moiety into the rigid aromatic polymer, thereby improving the moldability of the rigid aromatic polymer. Also, to improve the compatibility of the rigid aromatic polymer with the other polymer, it is possible to introduce a moiety compatible with the other polymer, which has the same structure as or a similar structure to the repeating unit of the other polymer, into the rigid aromatic polymer.
One example of such an attempt is disclosed by Japanese Patent Laid-Open No. 63-256622, which is a method of producing an aromatic heterocyclic block copolymer by reacting a particular aromatic oligomer with a monomer having a benzene ring provided with at least one carboxyl group and at least one amino group in a polyphosphoric acid. The aromatic heterocyclic block copolymers obtained by this method have rigid molecular chain moieties and soft chain moieties.
However, in the above method, the synthesis of the aromatic heterocyclic block copolymer is conducted while being heated in a polyphosphoric acid. Also, when the aromatic heterocyclic block copolymer obtained by this method is combined as a reinforcing material with another polymer to provide a molecular composite material, the aromatic heterocyclic block copolymer does not show a high compatibility with the matrix polymer because it already has a rigid molecular chain moiety such as a thiazole ring. Therefore, the aromatic heterocyclic block copolymer obtained by the method of Japanese Patent Laid-Open No. 63-256622 is not suitable for use in a molecular composite material.

Method of producing aromatic heterocyclic copolymer and molecular composite material containing same


A semi-automatic pistol is provided having a frame, a slide and an arced cam surface extending longitudinally on an inner surface of the slide. The pistol has a barrel mounted between the frame and the slide, and a firing pin mechanism mounted in the slide. A trigger is mounted on the frame. A trigger bar and a sear are also provided. The trigger bar includes a generally planar surface extending between the ends of the trigger bar. The first end is connected to the trigger and the second end has a sear disconnect surface to engage and disengage a sear rotatably disposed in the frame that engages an end of the firing pin. A tab is disposed at an angle to the generally planar surface, where the tab has a top curved surface to slide along the arced cam surface of the slide as the slide moves.

The present invention is directed to semi-automatic pistols. More particularly, the present invention is directed to a feature of a trigger bar for a semi-automatic pistol that provides for optimal timing of sear disconnection during a firing sequence.
In certain prior art automatic pistols, an thin upper portion of a stamped trigger bar of a semi-automatic pistol rides in an arced cam surface extending longitudinally on an inner surface of the slide adjacent to a side edge of the slide. It would be highly desirable to provide improved smooth and timely sear disconnection utilizing the trigger bar of a semi-automatic pistol and, subsequently smooth and reliable resetting of the various firing elements of an the semi-automatic pistol during a firing sequence. The present invention is directed to a modification of a portion of the trigger bar of an automatic pistol to provide improved operation.

Trigger bar cam for sear disconnect for a semi-automatic pistol


A system for efficiently storing and activating credential seeds that are embedded in authentication devices. Device manufacturers provide copies of credential seeds embedded in the devices to an authentication service. The authentication service stores the credential seeds for authentication devices in a pre-active credential seed data store. When a credential seed is needed to perform a real-time or near real-time authentication of a One Time Password, the credential is fetched from the pre-active credential seed data store, used to authenticate the OTP and injected into the active credential seed data store, which can be a database. Thereafter, the credential seed is fetched from the active credential seed data store for real-time and near real-time authentication of OTPs. The credential seeds can be stored in the data stores with additional information, such as user profile data, permissions and authorizations, OTP authentication algorithm information, metadata, OTP moving factor data, time-to-live, and other attributes.

An authentication device such as a token can generate a One Time Password (OTP) based upon an embedded secret called a credential seed. The token can process the credential seed with other factors such as a timestamp to generate a unique OTP that is used once to authenticate the token holder.
When a token generates an OTP, it is sent with the token identifier to an authentication service provider. For example, an OTP and identifier can be sent from a customer to a bank to authenticate the customer for online banking. The bank can send the identifier, OTP and other factors (such as a timestamp) to a third party authentication service for authentication. The third party looks up the credential seed based upon the token identifier, computes its own version of the OTP and compares it to the OTP received form the bank. If the third party's version of the OTP corresponds to the one received from the bank, the third party sends a message to the bank indicating a successful authentication. If not, an authentication failure message is sent to the bank.
A token manufacturer generally provisions its tokens with credential seeds by preloading each token with one or more unique credential seeds at its time of manufacture. It sends copies of the credential seeds along with their corresponding token identifiers to the party hosting authentication service. The credential seeds and identifiers are indexed and stored by the authentication service for lookup when needed. When large numbers of credential seeds that may be from different manufacturers are stored, it requires a significant amount of memory and resources to index, store and look up a particular credential seed. When credential seed files become larger, it introduces undesirable latency into the lookup and OTP verification process. It would be desirable to keep credential seed lookup tables that are used for real-time or near real-time authentication of OTPs as small and efficient as possible so as to reduce the amount of memory required to store them and improve the timeliness with which OTPs may be looked up and verified.
Many of the credential seeds sent to the authentication service are dormant because many of the tokens with which they are associated are pre-active, e.g., they have not yet been issued to users. Thus, many of the credential seed records that are indexed and stored in lookup tables used for live OTP authentication are not relevant to a token lookup operation at the time an OTP is received for verification by the service. The large number of pre-active credential seeds mixed with the active seeds can slow the lookup of active seeds in response to requests for real-time or near real-time authentication of OTPs.
In addition to the lookup performance challenge, a relational database storage that is typically used to store credential seeds may also have capacity limitations.
What is needed is a more efficient way to store credential seeds to facilitate lookups and speed the authentication process for OTPs while handling large volume of credential seeds.


A carbon material and a method of manufacturing the carbon material are provided. By affixing diamond particles onto a carbonaceous substrate in a condition in which etching caused by hydrogen radicals is unlikely to occur, the substrate etching rate can be suppressed, and the carbon material is allowed to have a diamond thin film having excellent adhesion capability. The carbon material has a carbonaceous substrate showing a weight decrease under a diamond synthesis condition, diamond particles disposed on a surface of the carbonaceous substrate, and a diamond layer having the diamond particles as seeds. The weight of the diamond particles per unit area is set to from 1.0×10−4 g/cm2 to less than 3.0×10−3 g/cm2.

Diamond has remarkable characteristics in terms of, for example, strength, thermal conductivity, and chemical resistance, and it is a material with very high potential for applications in mainly industrial materials in which such physical properties can be utilized. CVD diamond has long been known since the discovery of the deposition technique, and it has already been used widely in various industrial application fields, from the uses for cutting and grinding processes to various components including heat dissipating boards (for electronic circuit components), sensors (used in severe environments), optical window materials, detectors (for particle physics experiments), and speaker diaphragms. It is expected that the uses will expand more and more in the future.
The techniques for fabricating diamond for industrial uses can be classified roughly into two techniques, high-pressure synthesis and chemical vapor deposition. The former is the technique in which graphite, for example, serving as the carbon source that is the source material of diamond, is converted into diamond by applying high temperature and high pressure. This technique imitates the generation of diamond in nature. The latter is the technique in which a source material originating from carbon, the constituent element of diamond, is put into a gas state, is then subjected to chemical reactions such as excitation and decomposition with the use of electromagnetic waves or a heating element, and is restructured on a substrate into diamond.
Typical examples of the just-mentioned chemical vapor deposition technique include a plasma CVD (Plasma-assisted Chemical Vapor Deposition) technique, a hot filament CVD (HFCVD: Hot Filament Chemical Vapor Deposition) technique, and a chamber flame method. The differences between these techniques are that these techniques use different means of decomposition and excitation of molecules in vapor phase space, namely, electrons, ions, and radical species in plasma, a heating element, or thermal energy. That is, the ways of imparting energy are different.
The diamond synthesized by the foregoing techniques is formed in a film-like shape, and the diamond is obtained in such a form that the surface shape of the cover material is transferred thereto. By selecting the type of the source material gas, impurities such as boron, phosphorus, and nitrogen can be contained (doped) in the film. The film in which these elements are introduced shows semiconductor-like behaviors electrically, and as the content of the impurity increases, the characteristics of the film change into those of a conductor.
In depositing CVD diamond on various types of carbonaceous substrates, there is a difference in thermal expansion coefficient between the substrate and the CVD diamond layer. If there is an excessive difference in thermal expansion coefficient, the CVD diamond layer is compressed to the substrate or is put under stress in a stretching direction during the cooling process after the deposition and preparation, so the CVD diamond layer may be peeled off.
Conventionally, various techniques to solve this problem have been investigated. In an example, mechanical anchoring of the diamond layer is effected by roughening the substrate surface as a technique of increasing the adhesiveness between the CVD diamond layer and the substrate. For example, Patent Document 1 describes a method of forming a diamond layer on a substrate by a CVD technique, in which a substrate surface is roughened by a blasting process and a film is formed by a CVD technique on the resulting roughened surface. By this method, the film is formed in such a manner that the roughened surface is transferred thereto, whereby the contact area is increased. At the same time, the film is anchored to the substrate in such a manner that wedges are pushed into the film, whereby the adhesiveness between the film and the substrate is increased. The process according to this method can prevent peeling and cracks resulting from the contraction and expansion of the film due to the thermal expansion coefficient difference between the film and the substrate. This process is practiced as a very useful surface treatment technique.

Carbon material covered with diamond thin film and method of manufacturing same


A system and method for defining, structuring, and trading political event contracts is disclosed that implement a systematic process for defining political event contracts. The systematic process comprises a rigorous taxonomy of risk event classes that delimit the types of contracts to be defined. An event relevance scoring mechanism determines whether a derivative instrument embodying a specified event is economically warranted and useful to the marketplace as a mechanism for hedging risks not easily addressed through other market tools. The disclosed apparatus further comprises apparatus for modeling the value of a specified political event contract that captures both rational and intuitive analysis about an event using criteria based decision trees to provide highly structured calculation of relative probabilities. The tree components are weighted and compared by an analyst or other user to determine probabilities for various alternative outcomes to a specified political event.

Political event contracts are typically bilateral financial agreements pursuant to which one party agrees to pay a second party a fixed sum of money in the event that a triggering political event specified in the contract occurs. For example, the first party may agree to pay the second party one thousand dollars ($1000) in the event that a specified election is won by a specified candidate. If the specified candidate prevails in the election, the contract is said to settle at one thousand dollars ($1000) and the first party pays that amount to the second party. If, by contrast, the candidate loses the election, the contract is said to settle at zero dollars ($0) and no payment is made by the first party to the second party.
Once a political event contract is defined, it may be listed on an exchange and traded by persons or entities wishing to hedge against risks that they encounter in connection with their primary activities which correlate to the underlying event used to define the contract. For example, a company doing significant business in a specified foreign country may wish to hedge against the risk that its business will decrease if there is a military coup in that foreign country. If a political event contract is available that pays one thousand dollars ($1000) in the event of such a military coup, the company can hedge as much or as little of the risk it perceives from the coup by purchasing as many contracts in the market as it deems sufficient or appropriate.
A market for political event contracts may also include speculators. Speculators are market participants who try to profit from buying and selling contracts by anticipating future price movements. Speculators benefit such a market by assuming price risk and adding depth and liquidity to the market.
Political event contracts are today listed and traded on a number of internet marketplaces such as on the internet marketplace operated at www.intrade.com. The intrade marketplace describes itself as an exchange at which traders may express a view on a wide variety of world events by buying and selling event contracts at published prices. Contracts on the intrade exchange are divided into six event categories: politics, entertainment, financial indicators, weather, current events, and legal affairs. Further information concerning the intrade exchange is available at the company's website address above.
In the United States, the operation of marketplaces or exchanges such as that provided by intrade raises significant legal and regulatory concerns. In May 2008, the Commodity Futures Trading Commission (CFTC) solicited public comments on the appropriate regulatory treatment for event contracts. See 73 Fed. Reg. 25669-74 (May 7, 2008). One significant concern voiced by the CFTC was how to address the potential gaming aspects of some contracts which may not satisfy any real economic purpose, but instead merely provide a mechanism for wagering on events of general interest. Listing of such contracts on financial exchanges could convert such exchanges to surrogate gambling venues counter to public policy.
In addition to these regulatory concerns, defining and trading political event contracts on an established financial exchange in the United States present certain practical problems. For example, because the number of potential political events from around the world that can be used as the basis for defining a political event contract is immense, it is difficult to determine which particular events should be selected to maximize the economic value of the contract and its use as a hedging vehicle by market participants. Contracts that do not provide sufficient economic value as a hedging mechanism are not likely to attract significant liquidity, making such contracts less viable and ultimately less profitable for the listing exchange.
There is therefore a need in the art for a system and method for defining, structuring, and trading political event contracts that are of significant economic value so as to maximize trading in the contracts and the likelihood that they will receive regulatory approval for trading on regulated exchanges, rather than being deemed to represent simple gambling.

System and method for defining, structuring, and trading political event contracts


Construction elements of predetermined cross-sectional and end profiles are formed. These construction elements are useful in building construction. Included is an I-shaped element, a corner/connecting block and a D-shaped profile material. In addition, end cuts may be provided to provide interlocking assembly of the different elements, to establish a family of parts. The element can be pre-cut to desired lengths and assembled as kits, or as raw material, for use in all aspects of construction.

1. Field of the Invention
This is a continuation in part of co-pending application Ser. No. 333,705, filed Apr. 3, 1989, which is a divisional of application Ser. No. 016,364 filed Feb. 19, 1987, now issued as U.S. Pat. No. 4,817,356, which is a divisional of application Ser. No. 578,285 filed Feb. 8, 1984, now abandoned.
This invention relates to building construction systems and the elements thereof. In one aspect, this invention relates to wooden profiled lumber for use in the construction and related industries.
2. Background of the Invention
Wooden lumber commonly used by the building industry is of a rectangular cross section. However, for a large number of applications, the actual strength properties of lumber, as a building material, are far greater than structurally required. It would, therefore, be advantageous to design and engineer lumber material to the dimensions required to satisfy the minimum strength requirement. This would not only reduce the cost of material, but also reduce the weight of the lumber thereby lowering the transportation cost. However the size of the lumber material cannot be reduced below a minimum needed for providing a minimum surface area for joining together the various construction elements, or for satisfying other construction needs. For example, the thickness of lumber must be such as to allow adequate surface area for nailing the edges of two adjacent panels onto the edge of the lumber, or its width must be sufficient to provide adequate air or insulation in the spacing in a wall.
In addition, prior art building construction systems and elements require that the fasteners, i.e. nails, be able to withstand the full load being placed at the connecting points of a conventional frame structure. Ordinary rectangular studs can be twisted out of position due to structural stress. This can result in bent nails, separated joints, and structural weakness. Prior art building elements, because of the rectangular design, require more lumber and natural resources to manufacture. Also, the conventional rectangular cross section studs have significant weight and space requirements for shipping, handling and storing. In addition, the flat surfaces of the lumber allow high stacks to become unstable and become a potential safety hazard.
Prior art wooden lumber also has the disadvantage of warping and twisting as the lumber dries out. In addition, such conventional wood tends to split. Another disadvantage of conventional prior art building construction systems and elements is that the elements must be properly cut and fit together by highly skilled craftsman at the construction site to maintain accurate lines in construction, e.g. accurate right angles and proper horizontal and vertical placement. Significant amounts of experienced labor at the construction site is required. The fastening system is also relatively arcane in that brute force is required, and there are safety considerations in hammering nails or using staple guns.
Accordingly, it is an object of the present invention to provide a construction system and elements which comprise a family of parts which can fit together to provide more structural strength with less material. It is another object of the present invention to provide a construction system and elements which have less storage space requirements, and are conducive to more consistent building accuracy. It is yet another object to provide a construction system and elements which can be pre-cut to accurate dimensions, and then assembled in a relatively simple and convenient manner at the construction site.

Construction systems and elements thereof


A belt tensioner with a retainer can be brought into contact with a belt via a belt support for applying a tensile force. The retainer is joined at a distance from the belt support to a radial plain bearing and it can be swivelled about the axis of rotation of the radial plain bearing, whereby the tensioning and swivel movements of the belt support occur under the action of a coil spring. For a belt tensioner of this type, which with a compact construction runs essentially wear-free, it is suggested that the retainer is subject to the action of a spring, which exerts a force (F3) essentially parallel to the axis of rotation on the retainer, the said force (F3) counteracting the force (F1) exerted by the belt on the retainer.

1. Field of the Invention
The invention relates to a belt tensioner of the type for automotive vehicles.
2. Description of the Related Art
Typical belt tensioners are known, for example from DE-A-43 27 141 or DE-A-40 10 928. These belt tensioners are employed in motor vehicles for tightening the V-belt and comprise a retainer with a tension arm, which is fitted with an idler pulley at one end, that is applied to the belt, and which is joined to a radial plain bearing at its other end. The radial plain bearing includes a bearing bush part and a bearing pin part, whereby one of the parts is fixed to the tension arm and the other part is held spatially fixed. A rotary spring in the form of a spiral coil spring is wrapped coaxially around the bearing bush and bearing pin and is held by one end on the retainer and held spatially fixed at the other end. These known belt tensioners are fitted in a state in which the bearing bush and the bearing pin have been rotated against one another under the pretension of the rotary spring, so that the idler pulley already exerts a predetermined force on the belt. Due to the spring force of the pretensioned rotary spring, the belt is held under a predetermined tension, but the idler pulley can deflect or take up the slack if the length of the belt changes.
Due to the type of construction, the tension arm bearing the belt idler pulley must, however, be arranged off center in relation to the axial length of the radial plain bearing on the bearing bush or bearing pin. Consequently, the radial plain bearing is, however, stressed by tilting forces which cause increased wear. Attempts have been made in DE-A-43 27 141 to arrange the deflecting point of the swivel spring in the axial direction to the rotating axis so far removed from the radial plain bearing that the resultant of the force introduced into the radial plain bearing meets approximately the center of the axial length of the radial plain bearing. This is however only possible where there is sufficient installation space available.
The object of the invention is to develop a belt tensioner such that the susceptibility to wear is reduced with a compact, short construction.


The Mig protein gene of Streptococcus dysgalactiae, and the correspondingamino acid sequence, is described, as is the use of the Mig protein in vaccine compositions to prevent and treat bacterial infections in general, and mastitis in particular.

The present invention relates generally to bacterial antigens and genes encoding the same. More particularly, the present invention pertains to the cloning, expression and characterization of the Mig Fc-receptor protein from several Streptococcus bacteria species, and the use of the same in vaccine compositions.
Mastitis is an infection of the mammary gland usually caused by bacteria or fungus. The inflammatory response following infection results in decreased milk yield as well as quality, and causes major annual economic losses to the dairy industry.
Among the bacterial species most commonly associated with mastitis are various species of the genus Streptococcus, including Streptococcus aureus, Streptococcus uberis (untypeable), Streptococcus agalactiae (Lancefield group B), Streptococcus dysgalactiae (Lancefield group C), Streptococcus zooepidemicus, and the Lancefield groups D, G, L and N streptococci. Some of those species are contagions (e.g. S. agalactiae), while others are considered environmental pathogens (e.g. S. dysgalactiae and S. uberis).
The environmental pathogen S. uberis is responsible for about 20% of all clinical cases of mastitis (Bramley, A. J. and Dodd, F. H. (1984) J. Dairy Res. 51:481-512; Bramley, A. J. (1987) Animal Health Nutrition 42:12-16; Watts, J. L. (1988) J. Dairy Sci. 71:1616-1624); it is the predominant organism isolated from mammary glands during the non-lactating period (Bramley, A. J. (1984) Br. Vet. J. 140:328-335; Bramley and Dodd (1984) J. Dairy Res. 51:481-512; Oliver, S. P. (1988) Am. J. Vet. Res. 49:1789-1793).
Mastitis resulting from infection with S. uberis is commonly subclinical, characterized by apparently normal milk with an increase in somatic cell counts due to the influx of leukocytes. The chemical composition of milk is changed due to suppression of secretion with the transfer of sodium chloride and bicarbonate from blood to milk, causing a shift of pH to a more alkaline level. S. uberis mastitis may also take the form of an acute clinical condition, with obvious signs of disease such as clots or discoloration of the milk and swelling or hardness of the mammary gland. Some cases of the clinical disease can be severe and pyrexia may be present. For a review of the clinical manifestations of S. uberis mastitis, see, Bramley (1991) Mastitis: physiology or pathology. p. 3-9. In C. Burvenich, G. Vandeputte-van Messom, and A. W. Hill (ed.), New insights into the pathogenesis of mastitis. Rijksuniversiteit Gent, Belgium; and Schalm et al. (1971) The mastitis complex-A brief summary. p. 1-3. In Bovine Mastitis. Lea and Febiger, Philadelphia.
Conventional antibacterial control methods such as teat dipping and antibiotic therapy are effective in the control of many types of contagious mastitis, but the environmental organisms typically found in all dairy barns are often resistant to such measures. Vaccination is therefore an attractive strategy to prevent infections of the mammary glands, and has been shown to be beneficial in the case of some contagious mastitis pathogens.
However, the literature is limited regarding vaccination studies with environmental pathogens such as S. dysgalactiae and S. uberis, and variable results have been observed. In some cases, immunization has resulted in increased sensitivity to the specific organism and in other cases strain-specific protection has been obtained.
For example, previous studies have shown that primary infection with S. uberis can considerably reduce the rate of infection following a second challenge with the same strain (Hill, A. W. (1988) Res. Vet. Sci. 44:386-387). Local vaccination with killed S. uberis protects the bovine mammary gland against intramammary challenge with the homologous strain (Finch et al. (1994) Infect. Immun. 62:3599-3603). Similarly, subcutaneous vaccination with live S. uberis has been shown to cause a dramatic modification of the pathogenesis of mastitis with the same strain (Hill et al. (1994) FEMS Immunol. Med. Microbiol. 8:109-118). Animals vaccinated in this way shed fewer bacteria in their milk and many quarters remain free of infection.
Nonetheless, vaccination with live or attenuated bacteria can pose risks to the recipient. Further, it is clear that conventional killed vaccines are in general largely ineffective against S. uberis and S. agalactiae, either due to lack of protective antigens on in vitro-grown cells or masking of these antigens by molecular mimicry.
The current lack of existing mastitis vaccines against S. agalactiae or the contagious streptococcus strains is due at least in part to a lack of knowledge regarding the virulence determinants and protective antigens produced by those organisms which are involved in invasion and protection of the mammary gland (Collins et al. (1988) J. Dairy Res. 55: 25-32; Leigh et al. (1990) Res. Vet. Sci. 49: 85-87; Marshall et al. (1986) J. Dairy Res. 53: 507-514).
S. dysgalactiae is known to bind several extracellular and plasma-derived proteins such as fibronectin, fibrinogen, collagen, alpha-II-macroglobulin, IgG, albumin and other compounds. The organism also produces hyaluronidase and fibrinolysin and is capable of adhering to and invading bovine mammary epithelial cells. However, the exact roles of the bacterial components responsible for these phenotypes in pathogenesis is not known.
Similarly, the pathogenesis of S. uberis infection is poorly understood. Furthermore, the influence of S. uberis virulence factors on host defense mechanisms and mammary gland physiology is not well defined. Known virulence factors associated with S. uberis include a hyaluronic acid capsule (Hill, A. W. (1988) Res. Vet. Sci. 45:400-404), hyaluronidase (Schaufuss et al. (1989) Zentralbl. Bakteriol. Ser. A 271:46-53), R-like protein (Groschup, M. H. and Timoney, J. F. (1993) Res. Vet. Sci. 54:124-126), and a cohemolysin, the CAMP factor, also known as UBERIS factor (Skalka, B. and Smola, J. (1981) Zentralbl. Bakteriol. Ser. A 249:190-194), R-like protein, plasminogen activator and CAMP factor. However, very little is known of their roles in pathogenicity.
The use of virulence determinants from Streptococcus as immunogenic agents has been proposed. For example, the CAMP factor of S. uberis has been shown to protect vertebrate subject from infection by that organism (Jiang, et al., U.S. Pat. No. 5,863,543).
The xcex3 antigen of the group B Streptococci strain A909 (ATCC No. 27591) is a component of the c protein marker complex, which additionally comprises an xcex1 and xcex2 subunit (Boyle, U.S. Pat. No. 5,721,339). Subsets of serotype Ia, II, and virtually all serotype Ib cells of group B streptococci, have been reported to express components of the c protein. Use of the xcex3 subunit as an immunogenic agent against infections by Lancefield Group B Streptococcus infection has been proposed. However, its use to prevent or treat bacterial infections in animals, including mastitis in cattle, has not been studied.
The group A streptococcal M protein is considered to be one of the major virulence factors of this organism by virtue of its ability to impede attack by human phagocytes (Lancefield, R. C. (1962) J. Immunol. 89:307-313). The bacteria persist in the infected tissue until antibodies are produced against the M molecule. Type-specific antibodies to the M protein are able to reverse the antiphagocytic effect of the molecule and allow efficient clearance of the invading organism.
M proteins are one of the key virulence factors of Streptococcus pyogenes, due to their involvement in mediating resistance to phagocytosis (Kehoe, M. A. (1991) Vaccine 9:797-806) and their ability to induce potentially harmful host immune responses via their superantigenicity and their capacity to induce host-cross-reactive antibody responses (Bisno, A. L. (1991) New Engl. J. Med. 325:783-793; Froude et al. (1989) Curr. Top. Microbiol. Immunol. 145:5-26; Stollerman, G. H. (1991) Clin. Immunol. Immunopathol. 61:131-142).
However, obstacles exist to using intact M proteins as vaccines. The protein""s opsonic epitopes are extremely type-specific, resulting in narrow, type-specific protection. Further, some M proteins appear to contain epitopes that cross react with tissues of the immunized subject, causing a harmful autoimmune response (See e.g. Dale, J. G. and Beachey, E. H. (1982) J. Exp. Med. 156:1165-1176; Dale, J. B. and Beachey, E. H. (1985) J. Exp. Med. 161:113-122; Baird, R. W., Bronze, M. S., Draus, W., Hill, H. R., Veasey, L. G. and Dale, J. B. (1991) J. Immun. 146:3132-3137; Bronze, M. S. and Dale, J. B. (1993) J. Immun 151:2820-2828; Cunningham, M. W. and Russell, S. M. (1983) Infect. Immun. 42:531-538).
Chimeric proteins containing three different fibronectin binding domains (FNBDs) derived from fibronectin binding proteins of S. dysgalactiae and Staphylococcus aureus have been expressed on the surface of Staph. Carnosus cells. In the case of one of these proteins, intranasal immunizations with live recombinant Staph. Carnosus cells expressing the chimeric protein on their surface resulted in an improved antibody response to a model immunogen present within the chimeric surface protein (Liljeqvist, S. et al. (1999) FEBS Letters 446:299-304).
Bacterial Fc receptors (surface moieties that bind to immunoglobulin molecules through a non-immune mechanism, i.e., to the Fc portion of the antibody) are a class of binding proteins further categorized by their reactivity with different classes and subclasses of mammalian immunoglobulins. The type I receptor (also known as Protein A), the most extensively studied and characterized, has been isolated from Staphylococcus aureus, and binds to IgG types 1,2 and 4; this receptor type further exhibits cross-reactivity with IgA and IgM. The type II Fc receptor, found on a few Lancefield Group A streptococci, and the type III receptor (also known as Protein G), found on the majority of human group C and group G strains of streptococcus, have been reported to react with all four types of IgG. In the case of the type III receptor, binding to IgG is highly specific; the protein does not cross-react with IgA or IgM. The type IV receptor is found in certain bovine group G streptococci, and the type V receptor is found on certain strains of Streptococcus zooepidemicus. The type VI Fc receptor has been isolated from S. zooepidemicus strains S212 and RSS-212, and binds rat IgG with high affinity, i.e., 100 times that of Protein A binding, and 30 to 40 times as great as Protein G binding. (Boyle, et al., U.S. Pat. No. 4,977,082). For a discussion of Fc receptors, see Langone (1982) Adv. Immunol. 32:167 and Myhre et al. (1984) Basic Concepts of Streptococci and Streptococcal Diseases (Holm and Christensen, eds.) Redbook Ltd., Chertsey, Surrey, England.
Utility for Fc binding proteins have to date been limited to antibody detection and purification. With respect to clinical applications, a method of extracorporeal blood treatment of autoimmune disease which employs Fc binding proteins to remove antigen-antibody complexes has been proposed (see e.g. Fahnestock, U.S. Pat. No. 4,954,618). However, their use in vaccine compositions has not previously been described nor suggested.
Until now, the protective capability of the S. dysgalactiae Mig protein against mastitis has not been studied, nor has the S. dysgalactiae Mig protein been isolated or characterized.
Accordingly, the present invention provides Fc receptor proteins and uses therefor. In one embodiment, the invention is directed to a vaccine composition comprising a pharmaceutically acceptable vehicle and an Fc receptor protein. In certain embodiments, the Fc receptor protein is selected from the group consisting of:
(a) a Streptococcus dysgalactiae Mig protein comprising the amino acid sequence shown at amino acid positions 1 to 669, inclusive, of FIGS. 1A-1D (SEQ ID NO:4);
(b) an Fc receptor protein having at least about 70% sequence identity to (a); and
(c) immunogenic fragments of (a) and (b), said fragments comprising at least about 5 amino acids.
In some embodiments, the vaccine composition comprises and adjuvant.
In yet further embodiments, the invention is directed to a method of producing a vaccine composition. The method comprises the steps of
(a) providing an Fc receptor protein or an immunogenic fragment thereof, the fragment comprising at least about 5 amino acids, and
(b) combining said protein with a pharmaceutically acceptable vehicle.
In another embodiment, the invention is directed to a method of treating or preventing a bacterial infection in a vertebrate subject. The method comprises administering to the subject a therapeutically effective amount of a vaccine composition as described above.
In certain embodiments the bacterial infection is a streptococcal infection. Additionally, the bacterial infection may cause mastitis.
In yet another embodiment, the invention is directed to a method of treating or preventing a bacterial infection in a vertebrate subject comprising administering to the subject a therapeutically effective amount of a polynucleotide that comprises a coding sequence for an Fc receptor protein.
In certain embodiments, the bacterial infection is a streptococcal infection and may cause mastitis.
These and other embodiments of the present invention will readily occur to those of ordinary skill in the art in view of the disclosure herein.

Immunization of dairy cattle with Mig protein


The invention relates to a CO.sub.2 detector for the detection of CO.sub.2 in respiratory gases. In particular, the invention relates to medical devices which contain a CO.sub.2 detector disposed within the devices to allow detection of CO.sub.2 within respiratory gases.. The invention also relates to a method for determining the proper placement of an intubation device comprising inserting a tracheal tube having a CO.sub.2 detector disposed within, and observing whether the CO.sub.2 detector changes color in response to the CO.sub.2 which is present in respiratory gases.. The CO.sub.2 detectors of the invention comprise a pH sensitive dye and a solid phase support. The CO.sub.2 detectors of the invention may further comprise a phase transport enhancer which allows the CO.sub.2 detector to respond contemporaneously with the presence or absence of CO.sub.2 in a respiratory gas on a breath by breath basis.

1. Field of the Invention
This invention relates generally to medical devices, and more particularly to a detection device for determining whether a tracheal tube is properly positioned within the trachea of a patient.
2. Description of Related Art
There are a number of methods used by anesthesiologists to confirm that a tracheal tube has been properly positioned within the trachea of a patient. While anesthesiologists take great care to make certain that intubation of the esophagus does not occur, it is often difficult to know contemporaneously with insertion of the endotracheal device whether the device has unintentionally been placed in the esophagus. Undiagnosed intubation of the esophagus leads, in some cases, to death of the patient. It is therefore critical that there be a simple and accurate method of determining whether a tracheal tube has been properly positioned within the trachea of a patient.
In addition to the importance of proper placement of a tracheal tube, one problem which is encountered by anesthesiologists and others is the question of whether a patient is breathing. A device which confirms both proper placement of a tracheal tube and breathing would provide a much needed tool for use by the medical community.
One device which attempts to address the tracheal tube placement problem is described in "The Einstein Carbon Dioxide Detector," 60 Anesthesiology 613 (1983). In this article, a device is described which recognizes the well established fact that gases expelled from the trachea contain CO.sub.2 while gases within the esophagus do not.
The operation of the Einstein detector device is broadly based upon a visual indication of the carbon dioxide concentration found in expired gases. The technique described in the Anesthesiology article is based on the fact that gases expired from the lungs contain between 4% and 6% CO.sub.2 whereas atmospheric air, which is expelled from the esophagus, has a negligible amount of CO.sub.2. The device utilizes an adapter connected at one end to a mucous trap. A tube connected to the trap is filled with a liquid indicator solution, and the catheter end of the trap is positioned to be well below the indicator fluid level. The adapter is attached to the endotracheal tube, and expired gases are pumped through the indicator solution and are allowed to bubble therethrough. Utilizing a cresol red and phenolphthalein solution, a gradual color change from red to yellow occurs after several seconds upon proper tracheal intubation. No color change of the solution suggests esophageal intubation.
The Einstein detector has many drawbacks. Because the gas is bubbled through a liquid indicator, expired gas must be pumped through the liquid. This, of course, requires additional equipment not usually associated with a conventional tracheal tube, such as a conduit or sample tube, a mucous trap, and of course, the liquid chemicals themselves. Liquid chemicals have their own inherent disadvantages; in particular, they are impractical because they can spill. Further, the change in color does not occur until three to five seconds after trap chamber. The Einstein CO.sub.2 detector also does not follow the breathing pattern of the patient. In other words, the indicator used by the Einstein CO.sub.2 detector is not reversible on a time frame which would enable visual confirmation of breathing. Thus, the Einstein CO.sub.2 detector is limited in its ability to provide an indication of proper or improper intubation. It does not actively detect breathing; it only detects placement.
There are, of course, a number of different types of detectors associated with intubation devices which are used in varying applications. For example, U.S. Pat. No. 3,373,735 to Gallagher, teaches a device which indicates proper placement of a tube into a patient's stomach. After the tube is inserted into the stomach of a patient, a small amount of the stomach fluid is drawn into the tube to wet a color-change indicator. When the tube is properly inserted within the stomach of a patient, the indicator will turn red. If, however, the end of the tube has been improperly placed into the lungs, the indicator would remain a blue color. This device, of course, has nothing to do with the detection of respiration.
In addition to the Einstein CO.sub.2 detector, there are other carbon dioxide detectors for both medical and nonmedical applications. In the medical area, infrared and mass spectroscopy are used as CO.sub.2 detectors. In the non-medical area, U.S. Pat. No. 3,694,164 to Guenther discloses a system for sensing the carbon dioxide content of a gas. One embodiment taught by Guenther utilizes an infrared source which is mounted a fixed distance from a cell constructed on a conductive material such as aluminum. Radiation from the infrared source is focused onto the face of the cell and covers a major portion of the face of the cell. The face of the cell contains a small aperture which is sealed by a window which transmits virtually 100% of the infrared radiation which is absorbed by pure CO.sub.2 which fills the cell. Both the inner chamber of the cell and the face of the cell are fitted with thermistors which are connected to a sensing device for detecting the differences between the temperatures of the two thermistors. The source and sensor are turned on and allowed to come to temperature equilibrium in an atmosphere virtually free of CO.sub.2, and the sensor is set to a chosen reference. Upon exposure to an atmosphere of CO.sub.2 gas, the radiation formerly absorbed by the gas in the cell is decreased, whereas that radiation absorbed by the face of the cell is affected only slightly. The temperature differential allows the user to detect the content of carbon dioxide in the cell. While this device detects CO.sub.2, it is not colorometric, it is not rapid and is not positioned in a gas stream.
In another embodiment shown in the Guenther patent, a porous impregnated surface contains a color-change indicator which changes in accordance with the carbon dioxide content. This embodiment, however, does not discuss the ability of the device to cycle from one color to another at a rate which is on the same order of magnitude as is the rate of breathing. In general, Guenther is not directed toward providing a CO.sub.2 detector for use as a medical device.
U.S. Pat. No. 3,068,073 to Stanford discloses a device for detecting the presence and determining the content of carbon dioxide in gases. The gas containing an undetermined amount of carbon dioxide is passed through a solid reagent which includes alumina carrying parent container and changes color by contact with carbon dioxide. The quantity of carbon dioxide is determined by the length of time it takes for the color indicator to change the colors. In medical applications such as determining whether the intubation of the trachea has occurred, a rapid time change is preferred. Thus, such a time-consuming procedure would not be appropriate for medical applications.
It is therefore one object of the invention to provide a CO.sub.2 indicator which is contained within the respired gas stream of a tracheal tube.
It is a further object of the invention to provide a tracheal tube having a colorimetric CO.sub.2 detector which follows the breathing pattern of a patient.

CO.sub.2 indicator and the use thereof to evaluate placement of tracheal tubes