A polarization converting device for converting a light from a light source into a polarized light comprises a first prism having a first slant plane for receiving the light from the light source and dividing it into first and second lights with their polarized planes orthogonal, a first emergent surface from which the first light exits, and a second emergent surface from which the second light exits, a second prism having an incident surface opposed to the second emergent surface of the first prism, a second slant plane for reflecting and deflecting the second light from the incident surface so as to direct it to an optical path almost parallel to that of the first light, and a third emergent surface from which the second light reflected from the second slant plane exits, and a transparent layer carried between the second emergent surface of the first prism and the incident surface of the second prism, the transparent layer having a smaller refractive index than the first prism.

1. Field of the Invention
The present invention relates to a polarization converting device, a polarized light illuminating system using the device and an image display unit using the device.
2. Related Background Art
FIG. 1 is a constitutional view showing a conventional example of a projection type display unit.
This projection type display unit comprises a light source 1 consisting of a tungsten halogen lamp or metal halide lamp, a reflection mirror 2 for reflecting a part of light emitted from the light source 1, a heat ray cut filter 3 for absorbing or reflecting the heat ray of light incident thereupon directly or via the reflection mirror 2 from the light source 1, a condenser lens 4 for transforming the light after removing the heat ray to parallel light, a polarizing plate 5 for transforming the parallel light to linear polarized light, a liquid crystal light bulb 7 for modulating the linear polarized light in accordance with an image signal, a polarizing plate 8 for transimtting only component lying in a direction of transmission axis for the modulated linear polarized light, and a projection lens system 10 for projecting on larger scale the transmitted linear polarized light on to a screen, not shown.
FIG. 2 is a constitutional view showing another conventional example of a projection type display unit.
This projection type display unit has two polarizing beam splitters 6, 9 disposed before and after a liquid crystal light bulb 7, respectively, instead of two polarizing plates 5, 8 of the projection type display unit as shown in FIG. 1.
The projection type display unit as shown in FIGS. 1 and 2 has such a disadvantage that a linear polarized light component emitted from the light source 1 and transmitted through the polarizing plate 5 or the polarizing beam splitter 6 is only used for lighting the liquid crystal light bulb 7, and a linear polarized light component orthogonal to the above linear polarized light component is lost, so that the utilization efficiency of light is reduced to less than 50%.
A projection type display unit which improves the above disadvantage is that as described in Japanese Laid-Open Application No. 61-90584, as shown in FIG. 3.
In this projection type display unit, parallel light emerging through the condenser lens 4 enters a polarizing beam splitter 11, wherein its P polarized light component Lp is transmitted directly through an action surface 11a (a deposition film formed on a slant plane having two rectangular prisms bonded with each other) of the polarizing beam splitter 11, while its S polarized light component Ls is reflected therefrom at right angle and enters a total reflection prism 12. The S polarized light component Ls is reflected again at right angle by the total reflection prism 12 to emerge therefrom in the same direction as that of the P polarized light component Lp transmitted through the polarizing beam splitter 11. It is noted that the S polarized light component Ls is a polarized light component parallel to the action surface 11a of polarizing beam splitter 11, and the P polarized light component Lp is that orthogonal to the S polarized light component.
On the emergent side of the total reflection prism 12, a .lambda./2 optical phase plate 13 is disposed, in which the S polarized light component Ls emerging from the total reflection prism 12 has its polarized direction rotated 90.degree. by the .lambda./2 optical phase plate 13 and is converted to a P polarized light component Lp*. On the light emergent side of the polarizing beam splitter 11 and the .lambda./2 optical phase plate 13 are disposed wedge lenses 14, 15 for changing the optical path, whereby each optical path for the P polarized light component Lp transmitted through the polarizing beam splitter 11 and the P polarized light component Lp* converted by the .lambda./2 optical phase plate 13 is deflected and built up in such a manner as to intersect at a point P.sub.O on an incident side of the liquid crystal light bulb 7.
Accordingly, this projection type display units has a utilization efficiency of light twice as great as that as shown in FIGS. 1 and 2, because the liquid crystal light bulb 7 is illuminated with both the S polarized light component Ls and the P polarized light component Lp which are separated by the polarizing beam splitter 11.
As to the above projection type display unit as disclosed in Japanese Laid-Open Patent Application No. 61-90584, there is a problem that the light source 1 is usually made of a lamp, which is not a complete point or line light source, so that the light emerging from the condenser lens 4 is not completely parallel, and the P polarized light component Lp and the converted P polarized light component Lp* are not made parallel completely.
That problem will be described below with reference to FIG. 4.
The light emitted from the light source 1 having a finite diameter .phi. is converged by the condenser lens 4 disposed a distance 1 apart therefrom, but the emergent ray therefrom is not rendered a parallel light completely, producing unparallel light dispersed over a range of an angle 2.omega. (.omega.=tan.sup.-1 ((.phi./2)/1)). A light ray .alpha. of Unparallel light is not influenced by the polarizing beam splitter 11, but passes through an interface between the polarizing beam splitter 11 and the prism 12 to enter the .lambda./2 optical phase plate 13 and emerges therefrom as the ray containing both the S polarized light component and the P polarized light component. Also, a light ray .beta. is made the S polarized light component Ls at the polarizing beam splitter 11, in which after reflecting from the total reflection prism 12, it passes through the interface between the polarizing beam splitter 11 and the prism 12, and is reflected again by the polarizing beam splitter 11 so as to exit from the .lambda./2 optical phase plate 13 as the P polarized light component Lp* at a quite different position as indicated by a light ray .beta..sub.1, or be absorbed into an interface of the .lambda./2 optical phase plate 13 or transmitted directly as indicated by a light ray .beta..sub.2 in FIG. 4, thereby being lost.

Polarization converting device and polarized-light illuminating system using the device and image display unit using the device


A shock-resistant gun rack for holding guns. The gun rack includes a plurality of main support tubes. Each tube includes a movable carrier supported by a coil spring. Connected to the movable carrier is a generally U-shaped gun holder that is disposed exteriorly of the tube. In the event of a shock or impact, the U-shaped gun holder will move downwardly against the coil spring, compressing the same and in the process, absorbing the shock or impact. After such an impact, the coil spring will then bias push the carrier and connected holder to an upper position.

Gun racks are conventionally mounted in or on vehicles. Such conventional gun racks customarily include a pair of laterally spaced main frames with each main frame having a series of generally U-shaped supports secured thereto for receiving and holding a gun such as a shotgun or rifle.
A common problem associated with conventional gun racks is that the gun holders are not designed with shock-absorbing capabilities incorporated therein. Consequently, when the vehicle encounters a bump and there is a resulting shock or impact, it is not unusual for the gun holder to scar or scratch the gun or to impact against a scope secured to the gun and cause the scope to become misaligned. Moreover, such impact can cause the gun to be jarred from the gun rack or can even cause the gun to be accidentially discharged.
Today guns, particularly shotguns and rifles, are very expensive goods. Gun owners desire to protect their investment in such guns and desire to keep the guns from being scratched and damaged due to impact and shocks that are absorbed by the gun rack mounted in or on a vehicle.


The motor efficiency of a rotating X-ray tube having an anode assembly and a cathode assembly, can be greatly improved. The improved efficiency x-ray tube motor comprises a stator and rotor assembly having an air gap between the stator and rotor. The improved efficiency is achieved by reducing the air gap. The stator is operated at anode potential and electrically connected through an anode high voltage cable.

X-ray tubes used in medical diagnostic imaging are built with a rotating anode structure for the purpose of distributing the heat generated at the focal spot. The anode is rotated by an induction motor consisting of a cylindrical rotor built into a cantilevered axle that supports the disc shaped anode target, and an iron stator structure with copper windings that surrounds the elongated neck of the x-ray tube that contains the rotor. The rotor of the rotating anode assembly being driven by the stator which surrounds the rotor of the anode assembly is at anodic potential while the stator is referenced electrically to ground. The X-ray tube cathode provides a focused electron beam which is accelerated across the anode-to-cathode vacuum gap and produces X-rays upon impact with the anode.
Such an arrangement is typical of rotating X-ray tubes and has remained relatively unchanged in concept of operation since its introduction. Unfortunately, this type of motor arrangement with the combined stator and rotor is very inefficient. For example, in low speed steady state operation, where the rotor is driven with a frequency of 3600 rotations per minute (RPM), the peak motor efficiency is only approximately 8% and the average motor efficiency is only approximately 4.5%. In high speed steady state operation, where the rotor is driven with a frequency of 10,800 RPM, the peak motor efficiency is approximately 24% and the average motor efficiency is approximately 12%. The poor efficiency of the current motor design results in low torque delivered to the rotor assembly and a large amount of heat (typically 300-400 Watts in the run mode of operation) delivered to the tube housing environment.
The low efficiency of the existing design results from the need to employ a significant air gap between the rotor assembly and stator due to the differences in potential. As the stator operates at or near ground potential and the anode may be raised to 75,000 VDC positive with respect to ground, a large air gap on the order of 0.400 inches or greater is needed to maintain stable, discharge free operation in the current design techniques.
Several attempts have been made to improve the efficiency of the stator through other design techniques, such as increasing the length of the stator core and varying the material in the stator core. Unfortunately, such attempts have resulted in, at best, only incremental improvements in delivered torque to the rotor. For instance, a 40% increase in stator core length yields only a 25% improvement in delivered torque to the rotor assembly during steady state run operation. Also, it has been found that variations in the core material have little to no significant effect.
It would be desirable then to have a design which improves the efficiency of the stator and rotor assembly.


The system for managing bird populations includes a drone; a disruptor comprising an extension arm having a proximal end and a distal end, the proximal end being operatively coupled with the drone, and the distal end comprising a tool portion, where the tool portion comprises a piercing element constructed for engagement with one or more eggs in a nest; and a remote control system. The remote control system may comprise one or more remote control units and a monitor.

Certain species of birds, such as seagulls, may become a nuisance in urban areas when the birds nest on or near buildings or other areas used by humans. The birds may generally cause unsanitary conditions in the area and may become aggressive toward humans during breeding season. In an effort to protect their young or to try to gain access to food, the birds may even attack humans. In some areas reports of seagull attacks leading to injuries have become increasingly common.
Populations of such birds nesting on or near buildings, such as on roof tops or other areas, can be managed by removing nests or eggs, or by breaking eggs to prevent them from hatching. However, such work can be very challenging, as the nests can be in hard-to-reach areas that cannot be easily or safely accessed even by the use of long-armed tools, and because the birds may become aggressive when the nests are disturbed.
It is against this background that the present disclosure is made.

Device and method for managing bird populations


The present invention provides improved methods for manipulating recombinant DNA in gene cloning and expression. More specifically, the invention provides methods capable of altering a nucleic acid sequence present at the termini of a target sequence.

Recombinant DNA methodologies capable of amplifying purified nucleic acid fragments have long been recognized. Typically, such methodologies involve the introduction of a desired nucleic acid fragment into a DNA or RNA vector, the clonal amplification of the vector, and the recovery of the amplified nucleic acid fragment. Examples of such methodologies are provided by Cohen et al. (U.S. Pat. No. 4,237,224), Maniatis, T. et al., Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Laboratory, 1982, etc.
In some instances, the desired nucleic acid molecule can be readily obtained from a source material. The molecule can then be inserted into a suitable vector by either adding "linker molecules" (see Scheller et al., Science 196:177-180 (1977)) or by treating the desired molecule with a restriction endonuclease.
In other instances, however, the desired nucleic acid molecule cannot be obtained from a source material at a concentration or in an amount sufficient to permit gene cloning. In such a situation, it is necessary to amplify the nucleic acid molecule by, for example, template-directed extension, prior to introducing it into a suitable vector. Primer extension can be mediated by the "polymerase chain reaction" ("PCR"), or other means.
In the "polymerase chain reaction" or "PCR" the amplification of a specific nucleic acid sequence is achieved using two oligonucleotide primers complementary to regions of the sequence to be amplified (FIG. 1).
The polymerase chain reaction provides a method for selectively increasing the concentration of a nucleic acid molecule having a particular sequence even when that molecule has not been previously purified and is present only in a single copy in a particular sample. The method can be used to amplify either single or double stranded DNA. Reviews of the polymerase chain reaction are provided by Mullis, K. B. (Cold Spring Harbor Symp. Quant. Biol. 51:263-273 (1986)); Saiki, R. K., et al. (Bio/Technology 3:1008-1012 (1985)); Mullis, K. B., et al. (Met. Enzymol. 155:335-350 (1987); Erlich H. et al., (EP 50,424; EP 84,796, EP 258,017, EP 237,362); Mullis, K. (EP 201,184); Mullis K. et al., (U.S. Pat. No. 4,683,202); Erlich, H. (U.S. Pat. No. 4,582,788); and Saiki, R. et al. (U.S. Pat. No. 4,683,194) all of which references are incorporated herein by reference).
The ability to incorporate a gene sequence into a suitable vector is typically performed using restriction endonucleases. Thus, the vector and the desired gene sequence are treated with a restriction nuclease capable of producing compatible termini which can then be ligated together to form a covalently closed vector molecule. Preferably, the restriction enzyme is selected such that its recognition site is not present in the desired gene sequence.
It would be desirable to be able to generally alter the nucleotide sequences of a desired target sequence in order to permit it to be cloned into a suitable vector without using oligonucleotide linkers/adapters, and regardless of the availability or suitability of restriction sites. The present invention provides methods suitable for accomplishing these goals.

Use of exo-sample nucleotides in gene cloning


The present invention relates to a process for reacting isopulegol to menthone in the gas phase and to the use of the reaction products thus prepared as additives in foods, cosmetics, pharmaceutical products, tobacco formulations, household products, and laundry care products.

Menthol (1), the principal constituent of wild mint (Mentha arvensis), is among the most important aroma compounds in the fragrance and flavors industry and may take the form of four diastereomers. The oxidized diastereomers of menthol are referred to as menthone (2) and isomenthone (3), respectively. In the case of the diastereomers of menthone, the two alkyl substituents are in trans position; in the case of isomenthone, the substituents are in cis configuration.
On the basis of its odor and flavor profile, which is reminiscent of peppermint, menthone is employed in numerous formulations, for oral care and chewing gum applications, for example.

Menthone is customarily obtained by oxidation starting from menthol. Oxidizing agents used in this process are sodium chromate/sulfuric acid (Spec. Chem. 1987, 7, 193; Acta Chem. Scand. B 1979, 33, 148), sodium hypochlorite/acetic acid (J. Org. Chem. 1980, 45, 2030), ozone/ethyl acetate (JP 82180463) or pyridinium chlorochromate/silica gel (Tetrahedron 1979, 35, 1789). All in all, the oxidative methods for menthone preparation cannot be considered to be satisfactory, in view of the use of reagents which are of concern in relation to occupational hygiene and environmental compatibility.
DE 4236111 A1 describes a process for preparing menthone from menthol in a fixed-bed reactor, using a heterogeneous, copper-based dehydrogenation catalyst.
W. Treibs et al. (Chem. Ber. 1927, 60, 2335) describe the reaction of isopulegol (4) to menthone (2) in the presence of a catalyst which is obtained from copper acetate by precipitation with NaOH.

At a reaction temperature of 280° C., after the starting material has been passed over the catalyst, a mixture of menthone, isomenthone, and thymol can be isolated. The reaction regime disclosed therein is considered disadvantageous in view primarily of the awkward preparation of the catalyst and the high temperatures, which promote the formation of by-products.
Another means of preparing menthone, in this case starting from citronellol (5), is described in U.S. Pat. No. 4,134,919.

Here, over the course of four hours, at temperatures of 150-260° C. and under continuous hydrogen pressure, citronellol is reacted to give a menthone/isomenthone mixture. Catalysts used are copper-based compounds, e.g., Cu/Cr, Cu/Al, or Cu/Zn. Isomenthone and menthone can also be obtained in enantiomerically enriched form. In that case enantiomeric excesses of not more than 80% are attained.
Citronellal (6) as well can be used as a starting material for preparing menthone. Forti et al. (Synthesis 2001, 1, 52) describe the cyclization of citronellal in the presence of calcium phyllosilicates, aluminum nitrate, and iron nitrate, and also of a solution of NaOH in dichloroethane. The product mixture contains menthone and isomenthone in a ratio of 69/31.

In summary it is observed that the processes known from the prior art do allow the synthesis of menthone, even in enantiomerically enriched form, but entail the use of reagents which are harmful to health or the environment. Moreover, the processes disclosed only afford enantiomeric excesses of 80% at most. Moreover, the conduct of the reaction primarily in liquid reaction media, and the use of catalysts which are difficult to obtain, represent substantial disadvantages.
It is an object of the invention, therefore, to provide an Improved process for the catalyzed preparation of menthone, in which menthone in particular is obtained with an increased fraction of one enantiomer, more particularly in enantiomerically pure form.

Method for producing menthones from isopulegol in the gas phase


A slip element, including a substrate at least partially formed from a material degradable upon exposure to a fluid; and an outer surface disposed on the substrate. A method of removing a slip element including exposing a substrate of the slip element to a downhole fluid for degrading the substrate.

Slips are known in the downhole drilling and completions industry for anchoring components in a borehole. Slips are generally wedge-shaped devices that have teeth or other protrusions for "biting" into a tubular wall, typically a casing, as load is applied to the slips by components that are being anchored by the slips. When no longer needed, it is common to remove the components by milling or drilling operations. Current slip assemblies may include, e.g., a sleeve or series of segmented wedges made of cast iron or other materials that are difficult to remove by drilling or milling. The drilling/milling operations are time consuming and damaging to the bits used. Also, large chunks of cast iron or other materials often remain in the borehole after milling and are very difficult to fish out. As a result of the above, advances in slip assemblies are well received by the industry.


A coin mechanism for use with a vending machine where there is a coin barrel that receives the particular coins inserted vertically downwardly by the customer into a coin receiver. The coin barrel has an outer position where the coins can be inserted into the coin receiver and an inner position where the coins are checked by a coin discriminating mechanism, and, if proper, will allow the coin barrel to be rotated further by the customer to activate the vending machine to release the particular selected product. In the even the customer has made a mistake or has had a change of mind, the coin barrel is also allowed to be rotated by the customer, when in its outer position, to a position where the coin receiver is facing substantially downwardly so that the coins can be readily retrieved by the customer and are allowed to fall downwardly by the force of gravity.

The present invention relates to a coin operated vending machine, and more, particularly, to a multiple coin mechanism that receives the coins for operation of the vending machine and which allows the easy recovery of coins that need to be retrieved from the machine.
The use of various vending machines is, of course, well known and there are a great variety of such machines currently in use for a wide range of products to be dispensed. In the operation of such vending machines, the products desired by the customer are located securely within the particular vending machine, albeit, sometimes on display in that vending machine for the user. Thus, the customer inserts a predetermined combination of coins to reach the aggregate sum required for the specific product whereupon a coin discriminating mechanism acts to identify the particular coins that have been inserted into a coin slot to verify that the proper amount of money has been proffered to the vending machine and that discriminating mechanism thus allows the vending machine to release the product to the user upon correct verification of the amount of money.
In such machines, there are also a wide variety of coin mechanisms that are used to allow the user to insert the proper coins as well as a wide range of discriminating mechanisms that verify the coinage and allow the release of the product. One of the present coin mechanisms currently in use comprises a housing or body that is affixed to the vending machine and which has a coin barrel that can be moved between an outer position and an inner position. In the outer position, the coin barrel extends outwardly from the body and has an upwardly facing coin receiver into which the coins are inserted vertically downwardly. Within that coin receiver, there are a number of individual coin slots that are specially sized so as to receive a particular coin.
When the customer has inserted the proper combination of coins into the coin slots, the coin barrel containing those coin is pushed inwardly by the customer to its inner position where there is located the coin discriminating mechanism. The coin discriminating mechanism thus recognizes the number and denomination of coins that the customer has inserted into the coin slots and allows the coin barrel to be rotated in a direction, generally clockwise, in order to operate the vending machine to release the desired product. If, of course, the proper coins are not inserted into the coin slots, the coin discriminating mechanism will not allow the coin barrel to rotate at all so that no product is released from the vending machine.
One of the difficulties with the aforedescribed coin mechanism is that it is extremely difficult to remove a coin from the coin slot if an error has been made in the insertion of that coin. For example, if a dime is inadvertently dropped into a coin slot intended for a quarter, the dime will still drop into the quarter coin slot but the coin discriminating mechanism will, no doubt, recognize that a quarter is not in that coin slot and will not allow the coin barrel to rotate to operate the vending machine. In such instance, while the coin barrel can be returned to its outer position and the coins within the coin slots thus are visible, it is still very difficult to remove the small coin from the large slot intended for a quarter.
Since, in the outer position, the coin barrel is movable axially but not rotatable, it requires the user to try to fish out the incorrect coin, even to the extent of requiring tweezers, in an effort to correct the problem. It is a tedious task and one that some users become frustrated and simply leave the improper coin in the slot, thereby rendering the vending machine inoperative for the next user who is faced with the same problem of trying to remove the coin that is in the improper slot. The result is frustration on the part of the customers of the vending machine and potentially considerable downtime for a vending machine that would otherwise be generating revenue.
In other situations, there are times that the customer simply changes his or her mind and decides not to purchase one of the products within the vending machine after one or more coins has been inserted into the slots. At that point, the customer is interested in retrieving all of the coins, however, the same problem persists, that is, the coins are securely with the appropriate slot for the particular coin, however there still is no easy means of retrieving those coins back to the prospective purchaser without considerable difficulty.
Thus, it would be advantageous for the coin mechanism for such a vending machine to have some means of retrieving an inadvertently, incorrectly placed coin with ease and without a great deal of maneuvering or the need to use some retrieval implement or device to aid in the recovery of the coin.
In accordance with the present invention, therefore, there is a coin mechanism provided that overcomes the difficulties and problems of the present prior art coin mechanisms by allowing the user to easily and readily retrieve coins from the coin mechanism if the customer has a change of mind or has inadvertently inserted a coin into an incorrect coin slot.
In the present invention, the coin mechanism comprises a body, preferable of a molded plastic construction having a coin barrel that is both rotatable and axially movable within that body. The coin barrel includes a coin receiver that faces vertically upwardly when located in position affixed to the vending machine. Thus, the customer can insert the coins into the coin receiver vertically downwardly. The coin receiver itself, comprises a plurality of individual coin slots, each specifically designed to accept a particular denomination of coin.
When the coins have been inserted by the customer into the coin receiver, the coin barrel can be moved axially inwardly by the customer such that the coins enter the internal, secure area of the vending machine where a coin discriminating mechanism evaluates the number and denomination of the coins to be sure that the correct aggregate amount of money has been proffered to the vending machine by the customer.
If the proper coinage has, in effect, been inserted by the user and is recognized by the coin discriminating mechanism, that mechanism releases a locking system to allow the customer to rotate the coin barrel in a first direction to operate the vending machine and thereby have the product released to the customer.
The present coin mechanism also has a advantageous feature that allows the customer to retrieve the coins that have been inserted vertically downwardly into the coin receiver in the event one or more of those coins has been inadvertently inserted into the wrong coin slot i.e. one intended for another denomination of coin, or, alternatively, the customer simply has had a change of mind and wants the coins returned. In such event, the present coin mechanism allows the customer, when the coin barrel is in its outer position, to rotate the coin barrel in a second direction such that the coin receiver faces substantially downwardly and the coins can fall out by the force of gravity, thereby making it simple and easy for the customer to retrieve the coins. In the preferred embodiment, the first direction is the clockwise direction and the second direction is the counter clockwise direction of rotation, however, the directions may be opposite that of the preferred embodiment or, as a further alternative the first and second directions may be the same direction.
In any event, with the present invention, the customer can simply rotate the coin barrel, when in its outer position, and quickly retrieve any coins that have been inserted into the coin receiver by rotating the coin barrel to a position where the coin receiver is substantially facing the downward direction so that the coins can readily fall downwardly by the force of gravity to be retrieved by the customer.
Other features of the present coin mechanism will become apparent in light of the following detailed description of a preferred embodiment thereof and as illustrated in the accompanying drawings.


The solid scintillator according to the present invention is expressed by the following formula (1):

Inspection using a radiographic inspection apparatus such as an x-ray tomographic imaging apparatus (X-ray CT scanner) is performed in medical diagnosis, industrial inspection, and security fields. In general, the X-ray CT scanner includes an X-ray tube (X-ray source) which emits a fan-beam X-ray or a fan-shaped x-ray beam; an X-ray detector arranged facing the X-ray tube and having a large number of X-ray detection elements; and an image reconstruction apparatus which reconstructs an image based on data from the X-ray detector. An object is placed between the X-ray tube and the X-ray detector, and a tomographic plane thereof is imaged by fan-beam X-ray radiation.
The X-ray CT scanner emits a fan-beam X-ray and collects X-ray absorption data. The X-ray CT scanner repeats this processing by changing the radiation angle to the tomographic plane, for example, each by one degree. Then, the X-ray CT scanner analyzes the obtained data by a computer to calculate the X-ray absorption rate on the tomographic plane of the object and constructs an image of the tomographic plane according to the X-ray absorption rate.
As the X-ray detector of the X-ray CT scanner, there is used a solid scintillator which emits visible light by X-ray stimulation. The solid scintillator refers to a scintillator made of ceramic or single crystal.
It is preferable to use a solid scintillator as the X-ray detector of the X-ray CT scanner because the use of the solid scintillator as the X-ray detector can reduce the size of a detection element and thus can easily increase the number of channels for higher resolution.
As the solid scintillator used as a radiation detector such as the X-ray detector, conventionally there are known a single crystal such as cadmium tungstate (CdWO4), sodium iodide (NaI), and cesium iodide (CsI); europium-activated barium fluorochloride (BaFCl:Eu); terbium-activated lanthanum oxybromide (LaOBr:Tb); thallium-activated cesium iodide (CsI:Tl); calcium tungstate (CaWO4); cadmium tungstate (CdWO4); praseodymium-activated gadolinium oxysulfide (Gd2O2S:Pr) disclosed in Japanese Patent Laid-Open No. S58-204088 (Patent document 1); and the like.
Patent Document 1: Japanese Patent Laid-Open No. S58-204088

Solid scintillator, radiation detector, and X-ray tomographic imaging apparatus

Abstract: [Formula 1](M1-x-yGdxCey)3J5O12  (1)

Abstract: (wherein M is at least one element of La and Tb; J is at least one metal selected from the group consisting of Al, Ga, and In; and x and y are such that 0.5≦x≦1 and 0.000001≦y≦0.2). The transmittance of light having a wavelength of 550 nm measured at a thickness of 2 mm is equal to or greater than 40%. The solid scintillator according to the present invention can be manufactured at low cost, has a high light emitting power, and does not release Cd because Cd is not contained.


A prosthesis for replacement of the human knee joint, having separate femoral and tibial components which after implantation are freely relatively rotatable about a proximal-distal axis and are hingedly connected about a transverse axis posterior of the axis of rotational movement.

The knee is generally regarded as being the most inherently unstable of the joints of the human body, due in part to the complex of inter-related types of motions to which the several knee elements are subjected during the normal acts of walking, running, climbing and the like, which include relative sliding and rolling movements as well as rotation about both horizontal and vertical axes. In the past various mechanical approaches have been proposed in the attempt to approximate, through an artifical joint, the natural action of the human knee. Advanced conditions of disease or serious traumatic injury of the knee joint complicate surgical repair and efforts to simulate the natural knee motion through use of a prosthesis.
Under circumstances wherein the condyles of the knee are beyond acceptable repair by means of surgical replacement of only the articular surfaces thereof, it has been common practice to attempt joint reconstruction by means of one or the other of three general types of prothesis, which are: a first type which relies on a mechanical hinge, a second which is characterized by a ball-and-socket arrangement, and a third in which the femoral and tibial components are unconnected. Each of these has typical advantages and disadvantages of implantation and of therapeutic value.
The general objects of the present invention are to provide a new and improved joint prosthesis, generally of the hinged type, for the replacement of a seriously impaired human knee, which combines the mechanical strength of a pintle hinge with rotational freedom, which situates the horizontal pivot in a natural location posteriorly offset from the location of tibial-femoral contact, which affords ease of alignment and assembly during its surgical installation, and which incorporates means for absorbing any shock of engagement between the femoral and tibial components.


Implementations described and claimed herein provide implantable electronic devices having a thin film feedthrough and methods of manufacturing the same. In one implementation, an implantable electronic device includes a housing enclosing one or more internal electronic components within a hermetic environment. A feedthrough port is defined in a wall of the housing. A thin film feedthrough has a feedthrough body extending through the feedthrough port. The feedthrough body provides one or more electrical pathways between external contacts and internal contacts. The external contacts are disposed outside the hermetic environment, and the internal contacts are electrically connected to the one or more internal electronic components at an internal connection junction. A hermetic junction is disposed in the feedthrough port isolating the thin film feedthrough from the housing.

Treatment and/or monitoring of various types of medical conditions may utilize implantable electronic devices (IEDs). Such IEDs may include, without limitation, implantable pulse generators (IPGs), implantable cardiac monitors (ICMs), and the like. IPGs generate an electrical current for delivery to a target location of a patient for treatment. For example, pacemakers and implantable cardioverter defibrillators (ICDs) drive an electrical current into cardiac tissue to treat various cardia conditions. Similarly, neuromodulators or neurostimulators deliver electrical current into particular regions of the spinal cord or other body system to manage chronic pain and/or actuate or otherwise control an aspect of that body system. ICMs, on the other hand, are generally used to monitor heart function and/or other electrical signals without administering electrotherapy.
IEDs typically include a housing that isolates internal electronic components from tissues and bodily fluids surrounding the IED. Discrete electrical signals are passed through the housing along an electrical pathway between the internal electronic components within a hermetic environment and external electronic components outside the hermetic environment. Conventionally, the electronic pathway is a feedthrough comprised of conductive elements assembled within a dielectric material through a process providing a hermetic seal between the dielectric materials and the conductive elements.
Such conventional feedthrough assembly procedures are often cumbersome, complex, and unaccommodating for disparate configurations and/or treatment applications. For example, a number of conductive elements may range from a single conductor to hundreds, with the inputs and outputs needed for passing each conductor through varying depending on the electrical current and/or sensitivity parameters of the treatment application. Further, a size, shape, material, and/or location of each of the conductors is often dependent on an input/output from the internal electrical components, and connection methods for each end of the conductors varies based on whether the connection is within or outside of the hermetic environment.
The hermetic seal of the feedthroughs are commonly created using a high temperature reflow, brazing, or sintering process, where the choice of material for the feedthrough must be carefully selected to provide sufficient thermal stability during the process. This material selection thus limits the ability to adapt aspects of the feedthrough to accommodate various configurations and/or treatment applications. With the complexity and number of input/outputs for IEDs continuing to grow with the enhancement of therapeutic and diagnostic capabilities, there is a need in the art for a customizable IED that is less expensive and labor intensive to manufacture. It is with these observations in mind, among others, that various aspects of the present disclosure were conceived and developed.

Implantable devices with thin film feedthrough


A patient lift including a lifting member and a hoist assembly connected to the lifting member. The hoist assembly has an enabled state to move the lifting member between a raised position and a lowered position, and a disabled state wherein the hoist assembly cannot move the lifting member between the raised and lowered positions. An elongated switch member descends from the hoist assembly such that the switch member is reachable by an operator. Urging the switch member in a first direction in an axial sense along the length of the elongated switch member or a rotational sense about the length of the elongated switch member, places the hoist assembly in the enabled state or the disabled state. Urging the switch member in a second direction different from the first direction places the assembly in the other of the enabled state and the disabled state.

Patient hoists, also referred to as patient lifts, are commonly used to raise, lower, and transport patients who are disabled or who otherwise have mobility problems. Two common types of patient hoists are the stanchion-mounted hoist and the ceiling hoist. Stanchion-mounted hoists often have a hoist assembly situated at the upper end of a stanchion having a wheeled base, whereby the hoist assembly can be wheeled to different locations. A lifting member (e.g., a spreader bar bearing a patient harness, a sling, or a spreader bar bearing a harness or sling) descends from the hoist assembly on a strap, cable, or other flexible length of material which may be wound or unwound from a motorized spool situated within the hoist assembly. Thus, for example, the hoist might be wheeled to position the hoist assembly and lifting member over or adjacent to a patient; the lifting member can be lowered to receive the patient; and the hoist assembly may then raise the lifting member and patient so that they may be wheeled elsewhere (e.g., to a bathtub) to be lowered and placed. Ceiling hoists are similar, but tend to have their hoist assemblies movably engaged to ceiling-mounted tracks such that the hoist assembly can be moved about the track from location to location, e.g., between a patient's bed and bathroom.
The controls for stanchion-mounted hoists tend to be on the stanchions and/or on the stanchion-mounted hoist assemblies, whereas the controls for ceiling hoists tend to be on wall-mounted controls and/or on the ceiling-mounted hoist assemblies. Wall-mounted controls can be problematic for ceiling hoists because the controls may not be within easy reach of the patient's caregiver while he or she is standing near the patient. Similarly, controls mounted on ceiling-mounted hoist assemblies can be too high to conveniently reach (if they can be reached at all): a user may need to fetch a stepladder or stool to adjust the controls and difficulties may arise if the patient is suspended below the hoist assembly in the region where the caregiver needs to situate the stepladder/stool. Out-of-reach controls pose particular problems when a lifting operation needs to be urgently terminated, e.g., if lifting causes pain to the patient, or if it appears during lifting that the patient is in danger of falling. For this reason, ceiling hoists sometimes bear emergency stop or "lockout" switches that can be conveniently reached by caregivers standing next to or below the hoists. A common switch of this type resembles a pull-cord for an electric light, and has a flexible cord descending from the hoist assembly. A first pull on the cord disables the hoist, i.e., halts lifting or lowering of the lifting member and/or halts other motion, such as motion of the hoist assembly along any associated ceiling-mounted track, tilting of the hoist assembly (or a portion thereof) with respect to the track, etc. A second pull on the cord then re-enables the hoist assembly, i.e., allows motion of the lifting member with respect to the hoist assembly and/or allows other motion. A disadvantage of these types of switches is that their use of the same type of (pull-and-release) motion for hoist activation and deactivation can lead to mistaken activation after deactivation occurs, owing to events such as caregiver error (e.g., the caregiver's hand "bouncing" on the cord during an emergency stop situation), owing to the cord's catching on an item in the cord's surroundings, or other factors.
Other emergency switches similarly allow hoist operation to be disabled upon pulling a flexible cord or strap, but a user must then actuate a second switch situated on the hoist assembly to re-enable hoist operation. Since the first (enable) switch (the cord) is separate from the second (enable) switch on the hoist assembly, this arrangement deters accidental re-enablement of the hoist assembly. However, re-enabling the hoist assembly is inconvenient and time-consuming owing to difficulty in conveniently reaching the second switch, as discussed above. It would therefore be useful to have available emergency stop or "lockout" switches for patient hoists which are readily reachable from the floor at areas below and/or adjacent to the hoists, and which allow disabling and re-enabling of the hoists from these areas, while protecting against accidental re-enablement.

Emergency stop (lockout) system for patient hoists/lifts


Perlite particles, after being expanded and treated with a silicone have the ability to selectively absorb hydrocarbons while rejecting water on or in which the hydrocarbons may be present. A carefully designed cartridge having an apertured top and an apertured bottom permits runoff water to percolate through a body of particulate perlite so that the desired separation can be accomplished. The cartridge in which the perlite is contained is easily removed from a catch basin when the perlite has become spent. The cartridge may then be opened and the spent perlite removed, after which the cartridge may be refilled with fresh perlite and replaced in the catch basin.

1. Field of the Invention
The present invention is in the field of pollution control and specifically relates to a reusable cartridge for use in a storm drain to prevent liquid hydrocarbons from being carried by runoff water into sensitive waterways.
2. The Prior Art
In U.S. Pat. No. 3,382,170 Pape discloses a method of removing an oil film from a body of water by using expanded perlite that has been coated with a silicone for preferentially absorbing the oil and rejecting the water. Perlite is a generic term for a naturally occurring siliceous volcanic rock. Variations of Pape's disclosure are found in U.S. Pat. No. 3,674,683 to Ranier; U.S. Pat. No. 3,770,575 to Ball; U.S. Pat. No. 4,142,969 to Funk et al.; and, U.S. Pat. No. 5,302,590 to Newman.
Of course one cannot simply fill the storm drain with treated perlite; that would greatly reduce the capacity of the storm drain to handle heavy runoff. Also, after it has absorbed several times its own weight in hydrocarbons, the perlite becomes spent and needs to be replaced.
To avoid interfering with the flow of large amounts of water through the storm drain, a pending U.S. patent application of a different inventor discloses the use of an insert that fits into the mouth of a storm drain and that confines the perlite to a space immediately adjacent the vertical walls of the storm drain. In this arrangement, at low runoff rates the water will trickle through the perlite filter, but at greater runoff rates the water will simply cascade over the filter, bypassing it.
Although in theory the perlite could be disposed loosely in the insert, that approach is not practical for several reasons. Turbulence of the water would flush the perlite away unless the perlite were contained. However, if the perlite is contained loosely in the insert, removal of the spent perlite and its replacement by fresh perlite would become a problem. Further, the flow pattern of the incoming stream might be heavier in one region than in another, and this could cause displacement of the loose perlite and/or the production of rat holes to such an extent that the filtering action would be impaired.
The present inventor has solved all of these problems by providing a cartridge to confine the perlite within the insert, which cartridge is replaceable, refillable, and reusable.

Filter cartridge for separating liquid hydrocarbons from water


Apparatus is provided for monitoring the level of a liquid in a reservoir, especially in the situation where the liquid is a high temperature, molten material. The device operates as a static-tube differential pressure sensor and includes an open-ended tube with one end adapted for direct immersion in the liquid and with the other end being in pneumatic communication with a conventional differential pressure transducer. The meniscus of the liquid entering the tube essentially acts as a diaphragm membrane and eliminates the need for an immersible diaphragm, as conventionally used with static-tubes. The device may actuate a controller for compensating any change in the liquid level from a reference.

This invention relates generally to the monitoring of a liquid level within a reservoir and specifically to such monitoring utilizing a type of static-tube level sensor and more specifically to such monitoring wherein the liquid is a molten alloy.
Extruding a molten alloy from a pressurized crucible through an extrusion nozzle onto a rotating chill surface is one of several technologically significant methods available for the continuous casting of continuous glassy alloy filaments, as representatively shown in U.S. Pat. No. 4,142,571 "Continuous Casting Method for Metallic Strips" issued Mar. 6, 1979 to M. Narasimhan.
The degree of transverse dimensional constancy along the length of the filament is sensitive to variations in the stream of extruded melt impinging upon the rotating chill surface and therefore sensitive to extrusion pressure at the extrusion nozzle. Nozzle pressure is determined by the total effect of the static head of the molten alloy above the nozzle and the gas over-pressure within the pressurized crucible. Thus, to maintain a substantially constant nozzle pressure during extrusion, either a compensating molten alloy flow to the crucible must be provided or the pressurization of the crucible must be increased accordingly. In either situation, it is fundamental to monitor the level of the molten alloy in the crucible.
It is known to use pressure-tube devices to sense a liquid level. These devices are attractive for such use owing primarily to their simplicity. However, substantial materials problems are frequently encountered in applying these devices for sensing the level of a high temperature, molten material. There are basically two types of pressure-tube level sensors: the static-tube in combination with an immersible diaphragm, wherein the differential pressure between the static head in the liquid and the tube pressure causes deflection of the diaphragm membrane which is correlated with liquid level; and the bubbler-tube, wherein one opening of the tube is placed in the liquid and a flow of gas is passed through the tube with the resulting back-pressure being correlated to the liquid level. The static-tube with diaphragm device is not suitable for immersion in a molten material as the high temperature environment likely will cause destruction of the diaphragm or, at the least, contamination of the melt. The bubbler-tube may be unsatisfactory where the bubbling action interferes with the particular metallurgical process, especially in a small scale, sensitive process, for example by gas bubbles being entrained in the extruded flow of the above described filament casting process.
The present invention overcomes these limitations by utilizing only a static-tube whereby the meniscus of the liquid in the static-tube essentially acts as a diaphragm.


A system includes a processor configured to receive a request from a mobile device to utilize a vehicle resource. The processor is also configured to determine that a first key has been used to start a vehicle a first time. The processor is further configured to determine that a second key has been used to start the vehicle a second time and approve the request based on the determination that both the first key and the second key were used to start the vehicle a first time and a second time respectively.

Utilization of mobile applications for various smartphone platforms, as well as mobile applications used to communicate with and control vehicle functions is a rapidly growing customer demand within the automotive field. Because vehicles have been provided with the capability to interface with, receive commands from, and grant control of functions to a smartphone, security measures must be taken to prevent unauthorized access to the vehicle via a smartphone or other mobile device. Previous solutions have included direct on-screen access via a vehicle screen to pair a device, but this can permit a limited-time user (someone who borrows the vehicle, for example) to pair to the vehicle. Another previous option included some form of time delay following a request for verification purposes and to prevent immediate access to a party for whom access may not be desired. This can be onerous, however.
In another illustrative existing example, systems and methods may provide for determining a first proximity status of a first mobile device with respect to a vehicle, and determining a second proximity status of a second mobile device with respect to the vehicle. Additionally, an accessibility of one or more functions of the vehicle may be configured based at least in part on the first proximity status and the second proximity status. In one example, a policy associated with one or more of the first mobile device and the second mobile device may be identified, wherein the accessibility is configured further based on the policy.


An exercise bar, for use by weight lifters in performing wide grip bench presses, which comprises a straight horizontally elongated relatively long central section of uniform diameter. The bar also employs two like straight downwardly and outwardly extending short inclined sections. The diameter of the inclined sections is equal to that of the central section. The inclined and central sections lie in a common plane. The upper end of each inclined section is integral with a corresponding end of the central section. Each inclined section intersects the central section with a like included angle. Each inclined section is adapted to be grasped by a corresponding one of the hands of the lifter when the bar is in use. The bar also employs two like straight horizontally elongated end sections of intermediate length which fall along a corresponding horizontal line and lie in the common plane. One end of each end section is integral with the lower end of the corresponding inclined section. The end sections extend outwardly from the inclined sections. The diameter of the end sections is equal to that of the central section. Each end section is adapted to have weights secured thereto when the bar is in use.

Weight lifters and other individuals who exercise using weights often practice what is called a bench press. The individual so engated lies flat on a bench, grasps a bar having weights at each end and first extends his arms straight upward to hold the weighted bar above his chest and then lowers the bar until it rests upon his chest. In this exercise the individual's wrists extend at right angles to the bar.
In order to exercise certain additional muscles, this exercise can be varied by modifying it into a wide grip bench press. In this modification, the user spreads his arms outward so that the separation of the hands is increased and the wrists are no longer disposed at right angles to the bar but rather the center line of each wrist intersects the bar at an acute angle. In the bench press, the arms are disposed at right angles to the shoulder. In the wide bench press the arms extend outward beyond the shoulder. Under these conditions, when the bar is raised, the wrists are subject to very severe strain and the weights on the bar must be reduced as compared to the weights used during a bench press wherein the strain is more upon the arms and less upon the wrists.
In this invention, the bar geometry is changed in such manner that the user can perform wide grip bench presses while the wrists are disposed at right angles to the portions of the bar held in the hands. This arrangement greatly reduces the wrist strain and enables the user to perform wide grip bench presses with much heavier weights and the desired muscle exercise is greatly enhanced.


Disclosed is an archwire with a varied cross section which is formed integrally with a hook. The archwire includes a customized archwire body corresponding to a setup model of patient's teeth, and the hook which is formed integrally with the archwire body. The archwire body is formed in such a way that at least one region has a cross section different from that of another region.

In general, orthodontic therapy is to straighten crooked teeth by bonding brackets to the teeth and placing and ligating an archwire to slots of the brackets, wherein the teeth are corrected by retracting the teeth using a restoring force of the archwire or controlling torque of the archwire.
A method for retracting six anterior teeth usually employs a loop technique or a sliding technique.
The loop technique includes bending a portion of an archwire to form loops, ligating the archwire to brackets, and anchoring the hooks to the brackets by a ligating wire to produce a retraction force.
FIG. 1 is a view illustrating a process of forming a loop according to the related art.
Referring to FIG. 1, a loop 1′ is formed by bending a portion of a wire 1 using a tool. If necessary, a wire hook 2 may be mounted to a portion of the wire beside the loop 1′.
And then, as illustrated in FIGS. 2A, 2B and 2C, the wire is ligated to brackets 4 bonded to patient's teeth.
Finally, the hook 2 is ligated to the brackets by other ligating wire 3.
FIG. 2A shows an early stage before the loop 1′ starts activation, and FIG. 2B shows an advanced stage in which retraction of the teeth is completed.
If the activation is completed, the loop 1′ is supposed to be disposed at a center of both brackets. Actually, if the teeth are retracted by about 2 mm, the hook 2 abuts against the bracket 4, so that the hook is not further retracted. As a result, the hook 2 already mounted should be removed from the wire, and a new hook should be mounted onto the wire beside the loop.
FIG. 2C shows a new stage in which activation starts again after the hook 2 is mounted onto the wire.
The wire hook 2 is commonly used even in the case of retracting the teeth by the sliding technique.
The sliding technique includes ligating an orthodontic archwire to brackets and linking a closed coil spring or an elastic power chain to a hook to produce a retraction force.
FIG. 3 shows a process of mounting a wire hook according to the related art.
Referring to FIG. 3, a hook 2 is mounted to a proper location of the archwire 1, and a closed coil spring is linked to the hook 2 to produce a traction force.
Since the hook is mounted to the archwire by hands, the degree of precision is lowered. In particular, since a lower end of the hook is fastened to the wire, there is a drawback in that a volume of the archwire is significantly increased.
In particular, the above drawback is remarkable in the case of lingual orthodontic treatment in which a space is limited.

Variable cross-sectioned orthodontic archwire equipped with integrated hook


An indoor air quality sensor designed to be utilized in a zone of a building to control the ventilation of the zone and the method of effecting such control. The sensor comprises a first sensor for sensing a selected leading indicator of contamination in the zone and providing an output signal representative thereof and at least one additional sensor for sensing at least one selected secondary indicator of contamination in the zone and providing an output signal representative thereof. A processor, utilized for generating an output signal representative of the indoor air quality in the zone, receives the output signals from the first sensor and the least one additional sensor and generates the output signal representative of the indoor air quality in the zone by influencing the output of the first sensor by an amount that is a function of the output signal of the least one additional sensor.

Indoor air quality is becoming an increasingly important issue in today's building environment, particular in commercial office buildings. In order to provide guidance to building and HVAC system designers, the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) has specified minimums for ventilation rates and indoor air quality that will be acceptable to human occupants and will avoid adverse health effects. These requirements were published in ASHRAE Standard 62-1989. This standard, entitled "Ventilation Standard for Acceptable Indoor Air Quality", presents a series of general requirements for ventilation systems and two alternative procedures for providing acceptable indoor air quality.
Outside ambient air is brought into the zone to correct for unsatisfactory indoor air quality. Outside air may be either substantially colder than the desired indoor air temperature or may be substantially hotter than the desired indoor air temperature. In either case the heating, ventilation, and air conditioning (HVAC) system that serves the particular zone is going to have to work harder to set the desired temperature in the zone when outside ambient air is brought into the zone in substantial quantities. This results in energy inefficiencies for the building. It is desirable in all cases to minimize the amount of outside air that is brought into the zone consistent with maintaining a satisfactory air quality in the zone.
The first such procedure for controlling indoor air quality in the ASHRAE standard is the Ventilation Rate Procedure and uses ventilation air of specified quality in a fixed quantity for the specific zone to achieve acceptable indoor air quality in the zone. The Indoor Air Quality Procedure, on the other hand, uses sensing of known and specifiable contaminants to control the amount of ventilation in order to achieve acceptable indoor air quality in the zone. In typical circumstances, the ventilation system is designed according to the "Ventilation Rate" or "Prescriptive" method, i.e., provide 30 cubic feet per minute (CFM) per person for N persons where N is the design occupancy level of the zone.
The Ventilation Rate Procedure does not use direct sensing of air quality. Instead, it defines the amount of outside air to be delivered to the space based on the design occupancy level of the zone. This method by itself does not insure acceptable air quality and frequently results in inappropriate higher energy costs, since the procedure requires an assumption of the worst indoor air quality and ventilates to correct for this condition at all times, even when the air quality in the zone is satisfactory.
The "IAQ" or "Performance" procedure allows modulation of the ventilation rate when occupancy falls below the design level. This procedure is to directly measure indoor air quality and control the amount of outside air accordingly. Utilization of the IAQ procedure reduces energy costs for the building by increasing outside air flow only when there is a specific need. The drawback to this approach has been the lack of availability of good, low cost air quality sensors and the fact that designers cannot comply until the building is actually occupied.
It is important to note that, utilizing current equipment, system designers can approach compliance with the Ventilation Rate Procedure but cannot comply with the more energy efficient IAQ Procedure that are specified in Standard 62-1989.
Up to now, two different sensing techniques have been used to determine air quality when attempting to meet the IAQ Procedure standard. The first is CO.sub.2 sensing and the second is VOC sensing. Each sensor does an adequate job on its own of sensing the parameter that it is designed to sense, but is inadequate in determining true air quality in the zone. In addition, these sensors have been expensive, bulky, and lack long term stability, requiring frequent calibration.
CO.sub.2 concentration alone has, in the past, been utilized to regulate the amount of ventilation that is brought into a particular zone. CO.sub.2 is generally seen as an indicator of the occupancy and activity by humans of the zone , since it is the occupants and their activity that generate the CO.sub.2. It is desirable to increase ventilation when the concentration of CO.sub.2 reaches a certain defined level. Absent other contaminants, the modulation of the ventilation based solely on the concentration of CO.sub.2 is a reasonable procedure to ensure an adequate indoor air quality.
CO.sub.2 is not, however, the sole indicator of indoor air quality. As previously indicated, such items as the level of VOC's, temperature, and the relative humidity also are indicators of the indoor air quality. Of particular interest at the present is the level of VOC's. Such organic compounds typically escape from the fabric utilized in the furnishings of offices over a period of time. For example, the organic compound formaldehyde frequently contaminates the indoor air as it escapes from newly laid carpet. Organic compounds are also generated during the remodeling of spaces by glues, paints, and stains.
There are sensors that will very accurately sense a great number of individual organic compounds and accurately provide the concentration thereof. At present, such sensors are limited to very expensive laboratory instruments and are not practical for use in individual zones of buildings. Accordingly, the VOC sensing that is practical and cost effective for use in air conditioned zones is in general not very selective with respect to which organic compound is present and additionally does not provide a very accurate indication of the level of concentration. As a result of these limitations, reliance on VOC sensing within the zone as the sole indicator of the indoor air quality is not practicable.
It would be a distinct advantage in the industry to develop a low cost CO.sub.2 /IAQ sensor that is cost effective enough to be applied on a zone by zone basis. The IAQ sensor must sense contaminants other than CO.sub.2 and provide an output that reflects the sensing of those other contaminants. In addition, it must be available in both duct and wall mount versions. For the wall mount version, the size of the sensor must approximate the size of the common thermostat.
Additionally, such a low cost IAQ sensor could be modified to sense secondary indicators other than volatile organic compounds. In greenhouse applications, it is preferable to sense combinations using CO.sub.2 as the leading value combined with CO, Hydrocarbons or Ethylene. In fruit storage applications, CO.sub.2 may be combined with Ethylene or hydrocarbons. In tunnel applications, CO.sub.2 may be combined with CO or hydrocarbons. In pig farm applications, CO.sub.2 may be combined with Ammonia, CO or hydrocarbons.


A method for producing D-galactose from a dissolved solution of dried whey permeate or a liquid whey permeate is disclosed. The method comprises: removing non-sugar insoluble materials from the dissolved solution of dried whey permeate or the liquid whey permeate; removing protein from the dissolved solution of dried whey permeate or the liquid whey permeate from which non-sugar solid precipitates are removed; and removing ash, salts or both from the dissolved solution of dried whey permeate or the liquid whey permeate from which the proteins are removed. Another method for producing D-tagatose is disclosed. The other method comprises isomerizing D-galactose produced by the foregoing method.

There has been an explosion in demand for low-calorie and functional sweeteners capable of preventing excessive caloric intake, obesity and tooth decay owing to sugar consumption.
D-tagatose is an ideal low-calorie sweetener as an alternative sugar that can satisfy such consumer demand. D-tagatose has about 90% the sweetness of sucrose, thus being substantially identical thereto, but has 30% the calories of sucrose.
Further, it is known that D-tagatose, a stereoisomer of D-galactose, has low metabolic speed and absorption rate in the body, and thus can be used as a low-calorie sweetener without side effects (see: JECFA Sixty-third meeting, Geneva, 8-17 Jun. 2004—Food Additives).
Only 20% of D-tagatose is absorbed in the small intestine and the remaining 80% thereof is moved to the large intestine where intestinal microbes live and selectively accelerates the production of lactobacillus, thereby producing short chain fatty acids. Particularly, D-tagatose has a prebiotic characteristic of producing butyrate, which is known to help prevent colon cancer, in large quantities (up to 50% of the total short chain fatty acids). Further, D-tagatose is a natural sugar having a low-calorie value of 1.5 kcal/g and has attained GRAS (Generally Recognized As Safe) status under the U.S. Food and Drug Administration (FDA), thereby allowing use as a functional sweetener in foods, beverages, health foods, diet additives, and the like.
However, D-tagatose is not often found in nature and is a rare sugar present only in trace amounts in dairy products and some plants. In order to use D-tagatose as a low-calorie and functional sweetener, it is essential to develop a method for mass production of D-tagatose from inexpensive raw materials.
U.S. Pat. Nos. 5,002,612 and 5,078,796 disclose a method for producing D-tagatose by hydrolyzing lactose or lactose-containing materials by adding lactase to a mixture of D-galactose and D-glucose, removing optional D-glucose from the mixture, and then chemically isomerizing D-galactose into D-tagatose.
Thus, an essential intermediate in the enzymatic production of D-tagatose is D-galactose. Currently, supply of D-galactose developed up to now is restricted to hydrolysis of lactose
However, lactose prices vary due to unpredictable factors, such as amount of raw milk produced according to weather, demand for powder milk, changes in lactose consumption in third world countries, and the like, and exhibit a unique price pattern of repeating fall and rise in price. Such price fluctuations in the raw milk market make stable supply of raw materials for producing D-tagatose difficult.
According to the present invention, it is possible to obtain D-galactose from inexpensive whey permeate or dried whey permeate occurring in the process of producing whey protein isolates and to use D-galactose to produce D-tagatose. Therefore, stable supply of raw materials and price stabilization of D-tagatose can be ensured, thereby creating considerable added value.

Method of manufacturing D-galactose for use of the production of D-tagatose from whey permeate or dried whey permeate


A zoom lens system includes a positive first lens group, a negative second lens group, a positive intermediate lens group, and a negative image-side lens group. Upon zooming from the short to long focal length extremities, a distance between the first and second lens groups increases, and a distance between the second and intermediate lens groups decreases. The image-side lens group consists of two lens elements. The following conditions are satisfied:−6.0<f1/f2<−4.3,−5.4<f1/fIMG<−3.9, and0.3<D2/fw<3.0,                f1, f2 and fIMG designate the focal lengths of the first, second and the image-side lens groups, respectively, D2 designates a distance between the second lens group and the intermediate lens group, at the short focal length extremity, fw designates the focal length of the zoom lens system at the short focal length extremity.

1. Field of the Invention
The present invention relates to a zoom lens system applied to, e.g., a surveillance camera, a digital camera, and an interchangeable lens.
2. Description of Related Art
In recent years, there has been a demand for a zoom lens system that is miniaturized, has a higher zoom ratio, and has an extended (long) focal length at the telephoto side for photographing distant objects using a high zoom ratio. Furthermore, there is a demand to have a high optical quality for an object distance from infinity through to a close distance. However, generally, a large amount of aberrations (especially spherical aberration) occur in a zoom lens system that includes a telephoto range.
Japanese Unexamined Patent Publication Nos. H11-352401 (Patent Literature 1) and 2012-27261 (Patent Literature 2) each disclose a zoom lens system including a telephoto range and configured of a positive first lens group, a negative second lens group, a positive third lens group, and a negative fourth lens group, in that order from the object side; known as a positive-lead zoom lens system.
However, in the zoom lens systems disclosed in Patent Literature 1 and 2, the correction of various aberrations over the zooming range from the short focal length extremity to the long focal length extremity is insufficient, and the optical quality tends to deteriorate.


An expansible enclosure, suitable for use as a camper, trailer, display booth or display counter, having a box-like structure with six sides mutually interconnected at their respective peripheries, with telescoping frame facilities for expanding and contracting the enclosure by varying the distance between opposed sides, allowing expansion and contraction in three dimensions while maintaining substantial rigidity and integrity of the enclosure.

This invention relates to enclosure apparatus which can be expanded or contracted to various dimensions. It relates particularly to expansible mobile trailers which can be readily transported from one site to another. With the present invention, if utilized as an expansible mobile home, camper or work trailer, it can be contracted such that it is of moderate size and easily transportable from location to location, and then expanded in height, width and length to provide a relatively spacious and commodious mobile home, camper or work trailer.


A variable refrigerant flow (VRF) system for a building. The VRF system includes at least one outdoor VRF unit configured to heat or cool a refrigerant for use in heating or cooling the building. The at least one outdoor VRF unit includes a sub-cooler and a bypass expansion valve configured to control a flow of the refrigerant through the sub-cooler and an extremum-seeking controller configured to generate a sub-cooling temperature setpoint for the at least one outdoor VRF unit. The extremum-seeking controller is configured to determine a total power consumption of the at least one outdoor VRF unit, generate a sub-cooling temperature setpoint for the at least one outdoor VRF unit using an extremum-seeking control technique that drives the total power consumption toward an extremum, and use the sub-cooling temperature setpoint to operate the at least one outdoor VRF unit.

The present disclosure relates generally to a variable refrigerant flow (VRF) system and more particularly to a VRF system that uses extremum-seeking control (ESC) to control the operation thereof. VRF systems may be used in heating or cooling a building Refrigerant can be either heated or cooled within outdoor VRF units and delivered to indoor VRF units within the building The refrigerant can then be returned to the outdoor VRF units to be either heated or cooled again.
ESC is a class of self-optimizing control strategies that can dynamically search for the unknown and/or time-varying inputs of a system for optimizing a certain performance index. ESC can be considered a dynamic realization of gradient searching through the use of dither signals. The gradient of the system output y with respect to the system input u can be obtained by slightly perturbing the system operation and applying a demodulation measure. Optimization of system performance can be obtained by driving the gradient towards zero by using a negative feedback loop in the closed-loop system. ESC is a non-model based control strategy, meaning that a model for the controlled system is not necessary for ESC to optimize the system.

Variable refrigerant flow system with sub-cooling temperature optimization using extremum-seeking control


A control system for adjusting an antenna rotatably mounted on a vehicle to directly receive a transmitting signal from a geostationary satellite so as to apply it to a receiving equipment on the vehicle. The control system comprises a first sensor for sensing a first difference between a standard direction and a travelling direction of the vehicle, a second sensor for sensing a second difference between the travelling direction of the vehicle and a direction of the antenna, a microcomputer programmed to determine a third difference between the travelling direction of the vehicle and a direction of the satellite in accordance with the first difference on a basis of a predetermined difference between the standard direction and the direction of the satellite and to determine an adjustment angle for rotation of the antenna in accordance with the second and third differences, and an actuator for effecting for rotation of the antenna with the adjustment angle.

The present invention relates to a control system adapted to an antenna of receiving equipment, and more particularly to a control system for controlling an antenna mounted on a moving body such as an automotive vehicle, a ship or the like.
With remarkable developments of modern communication technology, mutual broadcast communications between broadcast stations located very far from each other on the earth are effectively relayed by synchronous or geostationary satellites located above the earth's equator in space. This means that radio or television programs broadcasted from distant localities on the earth can be seen and heard at homes, thanks to the satellite. As a result, it is desired to attain direct relay from the satellite to a radio or television receiver installed on an automotive vehicle, a ship or the like.

Control system for antenna of receiving equipment installed on moving body


The present invention relates to a method for regulating wrinkles and/or atrophy in mammalian skin comprising treating the skin with a safe and effective amount of salicylic acid and/or additional active component.

Skin is subject to abuse by many extrinsic (environmental) factors as well as intrinsic (chronoaging) factors. A common extrinsic factor is exposure to ultraviolet radiation. Whether extrinsic or intrinsic, the abuse results in wrinkling of the skin. To many people, skin wrinkles are a reminder of the disappearance of youth. As a result, the elimination of wrinkles has become a booming business in youth-conscious societies. Treatments range from cosmetic creams and moisturizers to various forms of cosmetic surgery.
Chronoaging results in the thinning and general degradation of skin. As the skin naturally ages, there is a reduction in the cells and blood vessels that supply the skin. There is also a flattening of the dermal-epidermal junction which results in weaker mechanical resistance of this junction. As a consequence, older persons are more susceptive to blister formation in cases of mechanical trauma or disease processes. (See Oikarinen, (1990) "The Aging of Skin: Chronoaging Versus Photoaging", Photodermatal. Photoimmunol. Photomed., Vol. 7, pp 3-4).
It is known to use salicyclic acid for the treatment of acne, see for example, U.S. Pat. Nos. 4,891,227 and 4,891,228, to Thaman et al., both issued Jan. 2, 1990 the disclosure of which are incorporated herein. Further, salacyclic acid has been used for the removal of wart, corns and calluses; for the treatment of psoriasis, seborrheic dermatitis and dandruff; and for the topical treatment of ringworm infection. A listing of commercially available products containing salicyclic acid will be found in the Physician's Desk Reference, 45th Edition, 1991, page 323. However, these prior art uses of saliciylic acid have generally involved short term treatments in which relatively large doses of the acid are applied (i.e., sufficient to cause significant irritation and often peeling) in order to obtain a cure or treatment of the particular condition, such as removal of comedones, as opposed to persistent treatment of normal aging skin.

Salicylic acid for regulating skin wrinkles and/or skin atrophy


Biologically pure strains of microorganisms capable of degrading indigo and indigo carmine are disclosed. A preferred strain is bacteria strain ATCC 55396. The bacteria is used for treating water polluted with indigo or indigo carmine by bringing the water into contact with the microorganisms or with enzymes extracted from the bacteria.

The present invention relates to microorganisms including bacterial strains capable of degrading indigo and indigo carmine. The present invention also relates to enzymes produced by these microbial strains which are capable of degrading indigo and indigo carmine.
Indigo is a well known dark blue dye. It is commercially available as a crystalline powder having a bronze luster. Indigo is insoluble in water, alcohol, ether, and dilute acids. It is slightly soluble in chloroform, aniline, and other nonpolar organic solvents. The 5,5'-disulfonate derivative of indigo is also a blue dye known as indigo carmine. In contrast to indigo, indigo carmine is soluble in water. The chemical structures of indigo and indigo carmine are shown below. ##STR1##
As in the case of many other dyes, the intense coloring of indigo and indigo carmine is due to the .pi. conjugation system. Rupturing the .pi. conjugation system of these compounds will result in decolorized products. Furthermore, because the .pi. conjugation system of indigo and indigo carmine is the same, substances which decolorize indigo are expected to decolorize indigo carmine as well.
Indigo is used extensively as a dye by the textile industry, particularly for denim products. The annual world production of indigo exceeded 14,000 tons by 1988 (Ref: American Dye Stuff Reporter, vol. A14, p. 154 [A-06141]). In many Asian countries where denim is manufactured, such as Hong Kong, Taiwan, China, etc., indigo presents an environmental problem. For example, about 4,000 tons of indigo are imported per year into Hong Kong, of which about 350 tons per year are consumed. A significant fraction of the remaining indigo is discharged into the environment by hundreds of textile and dyeing factories. Thus, indigo is a major man-made pollutant in the water streams of many Asian countries where denim is produced.
In recent years, efforts have been made to isolate microorganisms which are capable of degrading pollutants. Among these are several microorganisms which have been isolated because of their ability to degrade dyes. Microbes capable of degrading azo dyes have been identified by Horitsu et al., 4 Eur. J. Appl. Microbial 217-224 (1977); Idaka et al., 24B. J.S.D.C. 91-94 (1978); Kulla in Microbial Degradation of Xenobiotics and Recalcitrant Compounds, by Leisinger, et al., 389-399, Academic Press, London (1981); and Yatome et al, 13 NA J.S.D.C. 97:166-169 (1981). The initial strains were isolated for their ability to degrade food azo dyes (see Childs et al., 16 Biochem. Pharmacol. 1551-1561 (1967) and Roxon et al., 4 Fd. Cosmot. Toxicol. 419-426 (1966)). In later years, several investigators have identified species of Pseudomonas, Bacillus, and Flavobacterium able to degrade textile azo dyes. See Wilcox et al., 21 Forest Products Journal 50-52 (1970); Horitsu et al., supra; Idaka et al., supra; Yatome et al., supra; and Kulla et al., supra. More recently, it was found that triphenyl methane and crystal violet can be degraded by the yeast Rhodotorulae and the fungus Phanerochaete. See Kwasmiewska, 34 Bull. Environ. Contam. Toxicol. 323-330 (1985), and Bumpus et al., 54 Appl. Environ. Microbial. 1143-1150 (1988).
Until now, however, there have been no reports or suggestions for isolating a microorganism, or an enzyme produced by a microorganism, capable of degrading the dyes indigo and indigo carmine.
Accordingly, it is an object of the present invention to isolate one or more microorganisms which are capable of degrading the dyes indigo and indigo carmine.
It is a further object of the invention to isolate the enzymes produced by these microorganisms which enzymes are capable of degrading the dyes indigo and indigo carmine.
It is a further object of the present invention to provide a method for treating waste water containing the dyes indigo and indigo carmine by bringing the waste water into contact with microorganisms or enzymes produced by microorganisms which are capable of degrading indigo and indigo carmine.
It is a further object of the present invention to provide a method for bleaching a substrate, such as a denim, dyed with indigo or indigo carmine by treatment of the substrate with a suspension of a microorganism or an enzyme extracted from a microorganism capable of degrading indigo and indigo carmine.

Microbial degradation of indigo and indigo carmine with bacteria strain


An impact absorber for a vehicle includes an outer body including a cavity having an axis, and an inner body situated partially within the cavity for relative movement into the cavity when the absorber is subjected to an impact. The inner body has at least one lateral protrusion. A number of deformable units are located in the outer body at different positions along the cavity. The deformable units partially protrude into the cavity for successive engagements and deformations, one unit after another unit, along the cavity, by the protrusion of the inner body moving into the outer body, thereby absorbing the energy of an impact in different stages. Each deformable unit includes a rigid ball protruding into the cavity and a deformable plate fixed behind the ball.

Impart energy absorbing apparatus for motor vehicles are known, for example as disclosed in U.S. Pat. Nos. 3,392,599, 3,788,148, 4,006,647 and 5,984,354. Such apparatus, which are intended for use in the steering shaft of a vehicle, comprise a shaft enclosed by an outer cylindrical sleeve in a telescopic manner, and a number of balls rotatably mounted in the gap between the shaft and the sleeve. Upon impact, the sleeve and shaft collapse relative to each other, with the balls continuously rolling therebetween to absorb the impact energy.
Although part of the impact energy will be absorbed as described, much of the impact energy will remain unabsorbed and be applied continuously to the vehicle, hence injuring the driver. Furthermore, the structures of those apparatus are complicated and not easy to install or replace.
The invention seeks to mitigate or at least alleviate such problems by providing an improved impact absorber.


A backflow prevention assembly is disclosed which provides for detection of backflow conditions. The backflow preventer assembly includes a housing having an inlet, an outlet and a discharge opening. A pair of independent check valves is positioned within the housing between the inlet and the outlet. The check valves are mechanically and hydraulically independent from each other and each adapted to seal the inlet from the outlet during backflow conditions. A relief valve is positioned within the housing between the check valves to selectively seal the discharge opening. An alarm is coupled to the relief valve to provide a signal when the relief valve is opened indicating backflow and discharge conditions.

1. Field of the Invention
The present invention relates to backflow prevention assembly and, more specifically, to a backflow prevention assembly which includes a detection system for detecting backflow conditions.
2. Background Information
Backflow prevention assemblies have long been used to prevent a fluid source, such as a source of drinking water, from being contaminated with potentially unsafe liquids within a distribution system to which the fluid source is connected. A typical situation includes connection of drinking water supply to process systems of industrial buildings, steam boilers, pressure steam cookers, irrigation systems and fire suppression systems. Government regulations typically require the use of a backflow preventer when such cross connections are present.
Most modern building codes require that backflow preventers include a pair of independently spring-loaded positive check valves connected in tandem within the backflow preventer. The pair of check valves are provided so that each can serve as a backup in case the other should fail. In the event that both check valves should become fouled or otherwise fail, a discharge and a relief valve are often positioned between the first and second check valves. In this manner, if both check valves should fail during backflow conditions, the system will be emptied by the actuation of the relief valve opening the discharge. Examples of such check valves and relief valve systems can be found in U.S. Pat. No. 4,991,655 to McHugh. Further examples are Wilkins Backflow Preventer Models 975 and 975DA sold by Wilkins Regulator Division of Zurn Industries, Inc. The disadvantage of these prior art systems is that there is no indication as to when the relief valve is open and backflow condition is occurring. This presents a large problem in areas where the discharge is positioned in locations susceptible to flood damage, such as hidden areas or areas protected from freezing, or in areas where there is a high premium for water.
It is an object of the present invention to overcome the problems of these prior art systems. It is a further object of the present invention to provide a backflow prevention and detection system which provides a simple, effective and efficient mechanism for preventing backflow and indicating when backflow conditions are present.

Backflow prevention and detection system


The invention relates to a method, apparatus and computer program for reducing the number of data elements checkpointed in a system having at least one data store where operations on said at least one data store are recorded in a log. A point in the log is recorded. The oldest data element in each of the least one data store is determined and it is then determined for each of the at least one data store whether a logged representation of the data store's oldest data element is more recent than the point recorded. Responsive to determining that a data store's logged representation is more recent than the point recorded, it is realised that it is not necessary to force data elements from that data store to disk if the point recorded is made the point of restart for that data store.

Asynchronous transfer of messages between application programs running different data processing systems within a network is well known in the art, and is implemented by a number of commercially available messaging systems. These systems include IBM Corporation's MQSeries family of messaging products, which use asynchronous messaging via queues. A sender application program issues a PutMessage command to send (put) a message to a target queue, and MQSeries queue manager programs handle the complexities of transferring the message from the sender to the target queue, which may be remotely located across a heterogeneous computer network. The target queue is a local input queue for another application program, which retrieves (gets) the message from this input queue by issuing a GetMessage command asynchronously from the send operation. The receiver application program then performs its processing on the message, and may generate further messages. (IBM and MQSeries are trademarks of International Business Machines Corporation).
Messaging products such as MQSeries provide for assured once and once-only message delivery of messages even in the event of system or communications failures. This is achieved by not finally deleting a message from storage on a sender system until it is confirmed as safely stored by a receiver system, and by the use of sophisticated recovery facilities. Prior to commitment of transfer of the message upon confirmation of successful storage, both the deletion of the message from storage at the sender system and insertion into storage at the receiver system are kept 'in doubt' and can be backed out atomically in the event of a failure. This message transmission protocol and the associated transactional concepts and recovery facilities are described in international patent application WO 95/10805 and U.S. Pat. No. 5,465,328.
One key aspect of providing such an assured delivery of messages capability is the maintenance of a log in each system. A log is used to keep track of completed message activity and because a log is typically maintained a direct access non-volatile storage device (such as a hard disk drive), the information stored therein is permanently accessible. The log can therefore be used to recover the state of a system (i.e. queue(s) state) in the event of a failure thereof. Each time a recoverable message is sent to a queue, a record that the message was sent, including the message data, is written to the log, and each time a message is retrieved from a queue, a record that the message was retrieved is written to the log. In the event of a failure, the log is replayed to recover each queue to the state it was in at the point when the failure occurred.
A queue's message throughput in such a system can however be high. Further a log may be recording message activity for more than one queue. Consequently a large number of operations may be written to the log and having to replay the whole log at restart would not be feasible (this may involve replaying millions of records). In order to avoid the need to replay the entire log at restart, the queue manager periodically writes consolidated queue manager state to disk. This process is known as checkpointing. The data written at checkpoint time allows the queue manager to restart using only data that was written to the log relatively recently. A checkpoint typically hardens the current state of all queues which have changed since the previous checkpoint to permanent storage (disk).
FIGS. 1a and 1b illustrate a simplified view of logging and checkpointing according to the prior art. In FIG. 1a the state of a queue is shown in steps 1 through 8 and FIG. 1b illustrates the corresponding operations written to the log.
At step 1, messages A, B and C are put to a queue. This is recorded in the log (+A, +B, +C). An application then removes B from the queue (step 2) and this is reflected in the log (−B). Message D is subsequently added to the queue and so the queue now contains messages A, C and D (step 3). At this point the system takes a checkpoint by forcing the current state of the queue (as shown) to disk (step 4). A start checkpoint marker is placed in the log and only when checkpointing has completed is an end check point marker placed therein.
Whilst checkpointing is taking place, messages continue to be put and got from the queue and these operations are recorded in the log between the start and end markers. Thus, at step 5 message E is added to the queue and the log (+E). A is then removed from the queue (step 6) and recorded in the log (−A). At step 7, F is put to the queue and at step 8 C is removed from the queue. Once again this is all recorded in the log (+F, −C). At this point checkpointing finishes and the end checkpoint marker is placed in the log. Messages continue to be put and got from the queue and these operations recorded in the log (+G, −F). It is after F is got from the queue that the system fails and the current state of the queue (D E G) must be recovered.
As previously mentioned the whole log could be replayed in order to return the queue to its lost state. However, this would involve a large number of operations and is wasteful of both time and processing power. Thus because the consolidated state written to disk at step 4 (e.g. A C D) is recoverable, the operations stored in the log need only be replayed from the start checkpoint marker to the end of the log. Thus in this instance, A, C and D are safely on disk and only six operations have to be replayed to restore the queue. This is instead of 11 operations if the log had had to be replayed from the beginning.
Note, whilst FIG. 1a shows A, C and D being forced to disk at step 4, this is not necessarily the case. In reality what is forced to disk could be any queue state occurring between the start checkpoint marker and the end checkpoint marker. In any case checkpointing is well-known in the art and thus this should be understood by the skilled person.
Obviously FIGS. 1a and 1b show a greatly simplified view of the processing that takes place. It will be appreciated that in reality the message throughput in a messaging system will typically be far greater and that as a result the number of operations logged will be far larger. Consequently checkpoints have to be taken relatively frequently and because checkpointing involves forcing I/O it is expensive, especially considering that failures are rare occurrences and thus the majority of checkpoint data written will never be called upon.

Method, apparatus and computer program for reducing the amount of data checkpointed