The quantizer (2′) has an input network (5) which generates N different drive signals (Vij) as a function of the quantizer input signal (VI+−VI−). The input network (5) is designed in such a way that a value of the respective drive signal (Vij) which is greater than a comparison value indicates that the quantization threshold which is associated with the respective drive signal (Vij) has been exceeded. Furthermore, the quantizer has a switching network (9), which associates the N drive signals (Vij) with the N comparator inputs.

FIG. 1 shows a block diagram of a sigma-delta analogue/digital converter (SD-ADC). This has a closed control loop which includes a loop filter 1 (frequently also referred to as a noise-shaping filter), a quantizer 2 and a digital/analogue converter 3 (DAC). The SD-ADC illustrated in FIG. 1 is a so-called continuous-time SD-ADC, that is to say the loop filter 1 of the SD-ADC is an analogue, continuous-time filter, whose output value is valid throughout the entire time period. In contrast, so-called switched capacitor SD-ADCs are known from the prior art, whose loop filters have capacitances which are switched in order to model resistive filter components, and in which case the output signal is valid only at specific times.
The SD-ADC in FIG. 1 has an analogue signal X that is to be converted applied to its input. The difference between the analogue input signal X and the output signal from the DAC 3 is fed to the analogue loop filter 1, whose output side drives the quantizer 2. The quantizer 2 generates an oversampled digital signal Y on the output side, whose clock rate corresponds to the clock rate of the signal clk used to clock the quantizer 2. The quantizer 2 thus represents an analogue/digital converter. The mean value of the signal Y corresponds to the analogue input signal X. The SD-ADC illustrated in FIG. 1 is a multilevel SD-ADC (also referred to as a multibit SD-ADC). In the case of a multilevel SD-ADC the quantizer 2, as a multilevel or multibit quantizer, has a plurality of N quantization thresholds. In the typical implementation of the quantizer 2 as a flash quantizer, the quantizer has N comparators which operate in parallel, in which case each comparator has a specific associated reference REFj, where REFj<REFj+1. The references REFj are typically reference voltages. However, it is also feasible to use reference currents as references.
If the input signal to the quantizer 2 is in the region above REFj and below REFj+1, then all of the comparators with reference voltages of less than or equal to REFj produce a logic 1 at their output, while the comparators with reference voltages of greater than or equal to REFj+1 produce a logic 0 at their output. The resultant code of the output signal Y from the quantizer 2, which output signal Y has a length of N bits and results from the combination of the binary comparator output signals, is referred to, by analogy with a liquid thermometer, as a "thermometer code".
The output signal Y from the quantizer 2 is converted by means of the DAC 3 to an analogue signal which is compared with the analogue input signal X. When the control loop is in the steady state, the analogue input signal X and the output signal from the DAC 3 correspond to one another.
The loop illustrated in FIG. 1 is typically followed by a code converter (not illustrated) which converts the output signal Y from the quantizer 2 from the thermometer-code representation to a binary-code representation. Furthermore, a digital low-pass filter and a decimator (not illustrated) are arranged on the output side of the code converter, with the low-pass filter carrying out an averaging process, and with the decimator reducing the sampling rate.
The performance of the multilevel SD-ADC is governed primarily by the linearity of the internal DAC 3. The DAC 3 in general has N unit elements which—if no code conversion is carried out in the quantizer 2—are activated or deactivated as a function of the thermometer-code output signal, which has a length of N bits, from the quantizer 2. The unit elements are typically switchable unit current sources, with the output signal from the DAC 3 being obtained from the superimposition of the currents from the N unit current sources. The unit elements of the DAC 3 are ideally completely identical. In a real DAC, the unit elements are, however, slightly different, that is to say the output currents from the unit current sources are not completely identical in the activated state. There is thus a so-called mismatch, which results in non-linear distortion with respect to the output signal from the DAC 3. Since the output signal from the DAC 3 is applied to the control loop in the same way as the input signal X of the SD-ADC, any non-ideal property of the output signal from the DAC 3 is not suppressed in the control loop, and is evident as distortion in the signal Y.
In order to improve the linearity of the DAC 3, it is known for a so-called DEM block (DEM—dynamic element matching; frequently also referred to as a randomizer or scrambler block) to be provided directly at the input of the DAC 3 or within the DAC 3 (see FIG. 2). This results in the same unit elements in the DAC 3 not always being activated, but in different unit elements DAC 3 being activated at different times for a specific output signal from the quantizer 2, in which case the number of active unit elements remains constant. The linearity error of the DAC 3 is in this way reduced when averaged over time. The scrambling of the association of the unit elements of the DAC 3 can be achieved by dynamic scrambling of the code of the output signal Y from the quantizer 2, that is to say by interchanging the digits in the code signal. By way of example, a code "00111000" is generated on scrambling of a thermometer code "11100000" with a length of 8 bits. The scrambling process can be carried out using various DEM algorithms. DEM algorithms which are based on noise shaping are particularly important, in which the influence of the mismatch between the DAC unit elements is initially randomly distributed, and is then removed from the signal band.
In order to carry out the code scrambling, the DEM block 4 has digital logic which has a latency time, that is to say the output signal of the DEM block 4 reacts to a change in the signal Y only after a certain delay. This latency time acts as a dead time in the control loop and causes a deterioration in the stability characteristics of the control loop.
It is known from the document U.S. Pat. No. 6,346,898 B1 that any deterioration in the stability of the control loop caused by code scrambling can be overcome by placing a DEM block upstream of the reference inputs of the comparators within the quantizer 2′ rather than a DEM block 4 being placed between the output of the quantizer 2 and the input of the DAC 3 (see FIG. 3). In an SD-ADC such as this, the association between the references and the individual comparators in the quantizer 2′ is dynamically scrambled using a predetermined DEM algorithm. This approach is thus referred to as dynamic element matching in a reference path.
As a result of the scrambling of the references, different output bit lines of the signal Y are activated at different sampling times for one specific input signal to the quantizer 2′. Since each comparator output is permanently connected to one unit element in the DAC 3, different unit elements in the DAC 3 are thus also activated at different sampling times. The effect of the DEM block located outside the control loop, as shown in FIG. 3, is thus analogous to that of the DEM block 4 arranged within the control loop, as shown in FIG. 2, although the dynamic scrambling process shown in FIG. 3 does not involve any additional dead time within the control loop. Furthermore, in the case of the approach illustrated in FIG. 3, the influence of any mismatch within the quantizer 2′ (for example in the production of the references or with respect to the comparators themselves) is randomly distributed, and is removed from the signal band.
A network which comprises a resistor chain, coming from identical resistors, and identical current sources feeding the nodes in the resistor chain is known from the document "A Monolithic Microsystem for Analog Synthesis of Trigonometric Functions and their Inverses", G. Gilbert, IEEE Journal of Solid-state Circuits, Vol. 17, pages 1179–1191, December 1982. If the resistor chain is fed with a differential input voltage, Ex, this results in a parabolic potential profile over the individual nodes in the resistor chain. The maximum in the parabolic potential profile for the situation where Ex=0 is located at the central node in the resistor chain, and migrates in one direction or the other when the voltage Ex is increased or decreased.

Quantizer in a multilevel sigma-delta analogue/digital converter


A screening method for detecting the vulnerability of patients on clozapine therapy to developing agranulocytosis which comprises establishing the concentration of N-desmethylclozapine in the blood or bone marrow of said patient. In addition, a method of determining patient sensitivity to N-desmethylclozapine is provided which comprises collecting heparinized blood and assaying it for stem cell sensitivity to N-desmethylclozapine.

Agranulocytosis is an infrequent but potentially fatal complication associated with certain drugs that otherwise have less serious side effects and ordinarily are harmless to most patients. The complication is characterized by leukopenia (white blood count less than 2000/cu.mm.), a total absence of polymorphonuclear leukocytes (defined as less than 500/cu.mm.) and relative lymphopenia. If the disorder goes unrecognized and treatment with the drug is not discontinued, agranulocytosis will run a progressive course of increasing severity culminating in death from infection. If treatment with the drug is discontinued, complete recovery usually occurs. The period of greatest risk of agranulocytosis developing is in the first 3 to 12 weeks of treatment.
Antipsychotic drugs such as neuroleptics, tricyclic antidepressants and the benzodiazepines have been implicated in producing agranulocytosis. The most significant of these is the atypical neuroleptic drug, clozapine, whose chemical name is 8-chloro-11-(4-methyl-1-piperazinyl)-5H-dibenzo[b,e]-[1,4]diazepine. Clinical studies have shown that clozapine is effective as an antipsychotic agent in patients who are refractory and/or intolerant to classical antipsychotic drug treatment. The compound was found to be superior to standard neuroleptics; and approximately 30% of the patients conservatively defined as being refractory to these neuroleptics significantly improved with clozapine treatment. At the same time, it was found that clozapine does not cause parkinsonism or tardive dyskinesia to the same extent as classical neuroleptics and that it does not elevate prolactin secretion. With regard to tardive dyskinesia, long term treatment with clozapine appears to have a therapeutic effect against this neuroleptic side-effect, particularly the more severe form, tardive dystonia.
Despite its advantages, development of clozapine has been hampered by the apparent increased risk of agranuylocytosis. Based on clinical data, the incidence in patients treated for 52 weeks with clozapine is approximately 2%. Because of this risk, patients on a clozapine regimen have to be monitored continually for hematological signs of agranulocytosis onset. A simple screening procedure which reduced or eliminated the hematological monitoring required in clozapine therapy would be highly desirable in view of the considerable therapeutic potential of clozapine for patients who are unresponsive to or intolerant of the standard neuroleptic drugs.

Screening method for controlling agranulocytosis


The present invention relates to an improved and industrial friendly process for lactonization to produce compound of the Formula [I], from compound of the Formula [II] in presence of an inorganic compound as a suitable lactonizing agent, preferably alkali metal hydrogen sulfate, and crystallizing the obtained lactone product in a solvent; or treating compound of the Formula [II] in the presence of an inorganic compound preferably alkali metal hydrogen sulfate using phase transfer catalyst in heterogeneous phase followed by crystallizing the obtained lactone product in a solvent.

Lactonization, a well-known process is widely used in the preparation of statins. In this process δ-hydroxy carboxylic acid loses one molecule of water to form an intramolecular ester—a lactone. It is an equilibrium reaction as illustrated in the scheme below and therefore, some means of shifting the equilibrium to the "right" is required to achieve the product in high yield and purity.

Several methods are known in the prior art for lactonization of lovastatin or synthesis of simvastatin. All these methods broadly fall into two categories i.e. thermal dehydration or acid catalysed cyclization.
U.S. Pat. No. 4,444,784 to Hoffman et al., U.S. Pat. No. 4,582,915 to Sleteinger, et al., U.S. Pat. No. 4,820,850 to Verhoeven et al., and U.S. Pat. No. 6,307,066 to Keshava et al., describe the lactonization processes, by heating the statin acid and/or ammonium salt in a suitable solvent such as toluene, butyl acetate, ethyl acetate, cyclohexane to boiling, whereby the azeotropic mixture of the solvent and the water is removed by distillation and the reaction equilibrium is shifted to the formation of the lactone. The process of lactonization at reflux temperatures is complicated by the formation of dimeric impurity of Formula [III]. Moreover, its removal from the product is difficult, thereby affecting the quality of the final lactone product. To minimize dimerization, high dilutions are often used in the lactonization reaction, which is disadvantageous on large-scale manufacturing. Another disadvantage of these processes is that long reaction time is required for completing the reaction, thereby reducing the manufacturing capacity.

U.S. Pat. No. 4,916,239 to Treiber, U.S. Pat. No. 5,917,058 to Kumar et al., and U.S. Pat. No. 5,159,104 to Dabora et al., disclose lactonization processes by treating the open ring hydroxy acid form of the statins preferably in their ammonium salt form in the presence of a strong acid catalyst or a mixture of acid catalyst and water. The resulting lactonized product is isolated after completion of the reaction by the addition of anti-solvent selected from water, hexane, heptane or cyclohexane and the like. The strong acid catalyst used in the process varies from 1.2-1.5 molar equivalents, and is difficult to handle and poses industrially unacceptable disposal problems especially on an industrial scale. The reaction and the subsequent work-up takes about 9-12 hours thereby decreasing the efficiency of the process.
Similarly U.S. Pat. No. 6,562,984 to Peters, et al., describes the lactonization of statin acid or its salt in solvent selected from dichloromethane or acetonitrile under anhydrous reaction conditions in presence of organic or inorganic catalyst with the removal of insoluble hydrated complex formed during the lactonization reaction. However, in this method removal of the insoluble hydrated complex from the reaction mixture and thereafter its disposal reduces the efficiency of the process.
In addition, many of the lactonization methods of the prior art require the use of the strong mineral acid or an organic acid catalyst, thereby making the process hazardous and moreover these corrosive reagents require special care to handle. Furthermore, the generation of large amount of effluent requires special treatment procedures. All these require additional investments thereby increasing the cost of production. In addition, some of the prior art methods describe the lactonization reaction at subzero temperature thereby adding the additional utility costs.
Therefore, there is a need to develop an easy to operate, industrial friendly and yet cost effective process for preparing lactone compounds and still this process should ensure the formation of dimeric impurity to a level less than 0.1%. The present invention addresses these needs.

Process for lactonization in the preparation of statins


Nuclear fuel rod tubes of zirconium alloy are heat treated in an induction furnace to produce a protective oxide coating two to fifteen microns in thickness. The furnace is only slightly larger than the tubes and receives the endmost eight inches of the tube. The furnace is controllable in zones along the tube. To calibrate the furnace to produce the desired temperature profile, typically a flat profile at a temperature between 650.degree. and 750.degree. C..+-.1.5.degree. C., a temperature calibration probe is provided with spaced thermocouples for sensing the temperature developed in the probe at each of the zones when heated. The probe is made of inconel 600 stainless or the like, and is dimensioned and shaped to correspond closely to the dimensions of the fuel rod tubes, including having a closed chamfered end. At the opposite end the probe protrudes from the furnace, where the thermocouple leads are terminated. The leads pass through a potting compound in the probe, such as magnesium oxide. Whereas the probe conductive structures are substantially identical to the tube, the probe responds to the electromagnetic field in the induction furnace substantially the same as does the end of the tube, permitting calibration of the induction furnace zones for a desired temperature profile, e.g., flat along the length of the tube, notwithstanding differences in induced currents that would otherwise occur due to the end of the tube or the adjacent tube material.

1. Field of the Invention
The invention relates to the field of temperature measurement and control, in particular in an induction furnace for heating the end of a zirconium alloy nuclear fuel rod in the presence of an oxidizing gas, to form a protective zirconium oxide layer in an area of the fuel rod at which a fuel assembly structure tends to fret captured debris against the fuel rod. According to the invention, a probe that is configured to correspond to a fuel rod is provided with an array of spaced thermocouples for monitoring the temperature contour obtained in the induction furnace, enabling precise measurement and control of the temperature profile that occurs when a fuel rod is treated in the induction furnace under the same conditions.
2. Prior Art
In a nuclear power plant, coolant is heated in a vessel disposed along a primary coolant circuit, by nuclear fuel in the form of vertically elongated fuel rods carried in fuel assemblies. Each fuel rod comprises a stack of enriched uranium pellets in a hollow tube typically made of a zirconium alloy such as Zircalloy. The zirconium alloy presents a low nuclear cross section to neutrons that carry on the fission reaction leading to heating of the fuel. Zirconium is a highly active metal that, like aluminum, seems passive because a stable and cohesive thin zirconium oxide (ZrO.sub.2) film forms on the surface in the presence of oxygen, e.g., when exposed to air or water. Formation of the oxide layer is accelerated with heating.
Zirconium is advantageous for its subatomic properties, but is not the most durable of metals. It is possible to treat zirconium fuel rod tubes prior to their use in a reactor, to add a protective cladding layer that is more durable, thicker and/or more chemically resistant than the basic tube material. Such a cladding can comprise a plated-on alloy or a distinct metal. Heating of the fuel rod tube may be involved in the process. Typically the entire tube is treated; however, it is also possible to treat only particular areas that are considered vulnerable to corrosion or the like, for example the inside of the tube. Particular claddings are chosen for corrosion resistance, especially resistance to corrosion from reaction of the zirconium with iodine and other elements released during fission of the nuclear fuel. Examples of protective treatment of the inside or outside of fuel rod tubes are disclosed, for example, in the following patents:
______________________________________ 4,100,020 Andrews 4,233,086 Vesterlund 4,411,861 Steinberg 4,609,524 Ferrari 4,613,479 Foster 4,659,545 Ferrari 4,675,153 Boyle et al. 4,894,203 Adamson 5,026,516 Taylor 5,073,336 Taylor 5,137,683 Hertz et al. ______________________________________
In pressurized water and boiling water reactors, the fuel rods are grouped in fuel assembly structures that have vertically spaced grids for holding the fuel rods in a parallel array, whereby a number of the fuel rods can be handled as a fuel assembly unit. The liquid coolant is heated in a vessel by fission in the fuel rods, causing a vigorous and turbulent upward flow of coolant over the fuel rods due to convection. The fuel assembly grids are openwork panels disposed perpendicular to the elongation of the fuel rods, with spring structures that bear against the fuel rods to hold them in place. However, in the turbulent flow of the reactor coolant, loose metallic debris may be stopped by the grids, especially at the endmost grid facing the direction of flow. This captured debris vibrates against the fuel rods, leading to fretting damage to the zirconium alloy tube in the area of the endmost grid. A breach of the fuel rod tube can lead to release of fuel into the coolant, which is undesirable due to the resulting circulation of radioactive material with the coolant.
Fretting damage to the fuel rods has been found to occur primarily during the first cycle of their irradiation. Fissile heating of the fuel rods in the water coolant of the reactor during use thickens the zirconium oxide layer on the outer surfaces of the fuel rods and thereafter protects the fuel rods from fretting damage. Operational temperatures and pressures in a pressurized water reactor, for example, may be on the order of 300.degree. to 400.degree. C. and 150 bar. As described in commonly owned U.S. patent application Ser. No. 08/025,361, filed Mar. 2, 1993, it is possible to pretreat the fuel rod tubes to form a protective zirconium oxide layer prior to installation of the fuel rods. The protective layer is formed along the endmost four to eight inches (10 to 20 cm) of the fuel rod and reduces or eliminates fuel rod failure during initial use. This end portion of the fuel rod is the approximate length that protrudes from the lowermost grid of the fuel assembly, in the direction facing the coolant flow, i.e., the area in which the lowermost grid is likely to capture debris that will fret against the fuel rod.
The protective zirconium oxide layer can be formed by heating the fuel rod tube in the presence of oxygen. The thickness of the resulting ZrO.sub.2 layer is a function of the time of heat treatment, the temperature, and the oxygen concentration in the treating atmosphere, typically air. It is desirable to form a uniform coating that completely encompasses the end of the tube, and has a depth of two to fifteen microns. Formation of a protective oxide by heating in this manner is of course much easier than application of an alloy cladding, for example requiring a plasma arc or other process, such as in U.S. Pat. No. 5,227,129 - Bryan et al.
There are a variety of means by which a fuel rod tube can be heated, for example using convection, laser irradiation, application of a flame, etc. An advantageous method is heating via electrical induction. The end of the fuel rod tube is placed in an electrical induction furnace having coils coupled to an AC power source, for inducing a current in the metallic zirconium material. Induced eddy currents dissipate electrical power by resistance heating. This form of heating is advantageous in that the power can be concentrated at the area to be treated (at least subject to conduction of the heat to the remainder of the fuel rod tube).
Preferably, the induction furnace is only barely larger than the fuel rod or rods being treated. In this manner, the electromagnetic field intensity can be maximized by minimizing the gap between the coils (or the ferromagnetic material coupling the field to the fuel rod) in the magnetic circuit. To achieve uniform application of electromagnetic energy, a series of adjacent or spaced coil pairs can be disposed on opposite sides of the fuel rod tube, each of the coils in a pair being energized at opposite polarity and each coil pair encompassing a limited axial length of the fuel rod. These individual coil pairs can be controlled separately, for applying the precise power level needed to achieve uniform heating of the fuel rod tube.
It is advantageous to apply the minimum power necessary to obtain the required thickness of ZrO.sub.2 over all the end of the fuel rod tube to be treated. A uniform coating of ZrO.sub.2 that is of sufficient thickness over all the area of treatment requires precise temperature control. To achieve the uniform heating needed over the length of the fuel rod end, some means is needed to measure the induced heat from the respective coils, and to adjust or control the power level applied to the coils as necessary. It is not entirely adequate simply to apply equal power levels to each of the coil pairs, because the effects of the induction heating may be uneven even if the field strengths are equal, due to the variations in the eddy currents induced in the fuel rods occurring due to differences in geometry along the fuel rods. For example, the induced currents may vary between the center of the treated length of the fuel rod and the extreme end of the fuel rod, or between the center and the area at which the treated portion meets the proximal portion of the fuel rod, due to end effects and due to the adjacent conductive metal, respectively. The present invention concerns a method and apparatus for sensing the temperature effects of electromagnetic induction in a fuel rod by providing a temperature probe structured to simulate the conductive and/or resistive aspects of the fuel rod tube, and has an array of thermocouples disposed to measure the temperatures at specific spaced points. In this manner a temperature profile can be measured and used to adjust the electromagnetic field strengths of the coil pairs, for obtaining a desired temperature profile when the probe is replaced by an actual fuel rod to be treated.
Temperature probes for measuring the heat in a furnace are known generally. In a typical application, the probe is moved to different areas of the furnace in order to develop a temperature profile from a series of successive measurements. It is also possible to use an array of temperature sensors on a probe, for example as shown by U.S. Pat. Nos. 4,176,554 or 4,242,907, both to Kazmierowicz, or 4,098,122- Landman et al. For such uses, the spaced temperature sensing elements of the probe are intended to measure the ambient temperature at different points in the furnace or kiln. It is assumed that the ambient temperature as so measured is the temperature to which the workpieces will be heated when at the corresponding location. The furnace or kiln is then adjusted to obtain a desired temperature profile.
This technique cannot be used effectively if the presence or movement of the workpiece being heated in the furnace has an effect on the temperature to which the workpiece is heated. In a tunnel furnace, for example, cool workpieces entering the furnace reduce the ambient temperature there, other things being equal. Similarly, where a tunnel furnace has workpieces moving from a zone at one temperature into a zone at another temperature, it will take a certain time for the workpieces to reach the temperature of the new zone, assuming that the workpieces remain long enough to reach the ambient temperature at all. The reason for providing a probe having spaced temperature sensors is to obtain a measurement of the differences in temperature from point to point in the furnace, for example due to the workpieces, so that such effects can be addressed.
Temperature probes as disclosed in Kazmierowicz or Landman et al. are not suitable for measuring the temperature profile of an electromagnetic induction furnace, for adjustment of the field generating means as needed to develop the required temperature profile in workpieces when inserted to be heated. The electrical induction form of heating apparatus is particularly affected by the presence of the workpiece, because for the most part the heat is generated in the workpiece rather than in the ambient air of the furnace. Although indirect temperature sensing means could be installed in the furnace to sense the workpiece temperature at different points, this is a complex and expensive solution to the problem. According to the present invention, a probe having spaced temperature sensors is configured to resemble a workpiece, in particular the end of a fuel rod tube to be heated for producing a protective oxide layer, whereby currents induced in the probe and the temperature to which the probe is heated, closely model the situation for actual fuel rod workpieces.

Calibration fixture for induction furnace


A device for slowing the burning and smoke output of a resting cigarette between drags thereon by a smoker includes a base with an inclined or sloped open channel therein shaped to closely receive and cradle the burning end of a cigarette around about one-half the circumference of the cigarette. The cigarette is held in a sloped condition with the burning end downwardly. A passage extending along the length of the channel serves to provide air to the cigarette in addition to the air provided by the open side of the channel. The passage is dimensioned to provide a controlled amount of air to the cigarette and the dimensions of the passage may vary along its length to vary the amount of air supplied to the burning end of the cigarette depending upon its position in the channel.

1. Field:
The invention is in the field of ash trays.
2. State of the Art:
Ash trays in use today provide a receptacle for ashes from cigarettes as they burn and for cigarette butts after smoking of the cigarette has been completed. Ash trays usually also provide a rest for cigarettes to hold the cigarette as it burns, when not being smoked, but when the smoker desires to keep it lit and available for smoking.
With the current concern for reducing the smoke in the air that non-smokers breath, it would be desirable to reduce the amount of smoke released by a cigarette while not being smoked by a smoker, for example, the smoke released by a cigarette while resting in an ash tray between drags by a smoker.
In my U.S. Pat. No. 4,982,746 I disclose that the smoke output of a cigarette may be reduced as it sits in an ash tray by providing a channel in which the cigarette may be placed and which fits closely about the outside of the cigarette for at least a third of the circumference of the cigarette, and preferably for a half of the circumference of the cigarette. While this channel is effective to reduce smoke output, I have found that it can cause discoloration of the cigarette. Further, it does not result in the controlled burning necessary to ensure that the cigarette can be picked up and smoked normally after being in the channel for an extended time.

Device for slowing the burning of a resting cigarette


An intrinsic polarizer, including a sheet of PVA-type matrix that includes vinylene polymer blocks, the sheet defining a pass polarization axis and a block polarization axis perpendicular to the pass polarization axis, light having an electrical vector parallel to the pass polarization axis being substantially transmitted through the sheet and light having an electrical vector parallel to the block polarization axis being substantially absorbed by the vinylene blocks, the sheet exhibiting a dichroic ratio of more than 100.

Normally, light waves vibrate in a large number of planes about the axis of a light beam. If the waves vibrate in one plane only, the light is said to be plane polarized. Several useful optical systems can be implemented using polarized light. For example, in the manufacture of electro-optical devices such as liquid crystals display screens, cross polarizers are used in conjunction with an addressable liquid crystal interlayer to provide the basis for image formation. In the field of photography, polarizing filters have been used to reduce the glare and the brightness of specular reflection. Polarizing filters, circular polarizers or other optical components have also been used for glare reduction in display device screens.
Linear light polarizing films, in general, owe their properties of selectively passing radiation vibrating along a given electromagnetic radiation vector, and absorbing electromagnetic radiation vibrating along a second given electromagnetic radiation vector, to the anisotropic character of the transmitting film medium. Dichroic polarizers are absorptive, linear polarizers having a vectoral anisotropy in the absorption of incident light. The term "dichroism" is used herein as meaning the property of differential absorption and transmission of the components of an incident beam of light depending on the polarization direction of the incident light. Generally, a dichroic polarizer will transmit radiant energy polarized along one electromagnetic vector and absorb energy polarized along a perpendicular electromagnetic vector. A beam of incident light, on entering a dichroic polarizer, encounters two different absorption coefficients, one low and one high, so that the emergent light vibrates substantially in the direction of low absorption (high transmission).


A system for automatically electrically connecting electronic components, such as an input/output board and a power supply, with a motherboard includes attaching in a tray with electronic components with a frame. In one embodiment, a tray is pivotably attached to a computer housing frame and a connector extends from the under side of the tray. As the tray is pivoted about its axis, the connector is engaged or disengaged from a connector fixedly mounted on the motherboard. The connector on the motherboard has a flexible funneled opening to facilitate insertion of the pivoting connector. In another embodiment, a tray with electronic components can be quickly disconnected from the motherboard by lifting the tray straight up guided by frame tracks. By lifting the tray, a series of leads mounted on the tray are disengaged from the slot connector mounted on the motherboard. Advantageously, a method for disconnecting electronic components from a motherboard in a computer frame is disclosed.

1. Field of the Invention
The present invention relates to a computer, and particularly to a system to electrically disconnect and connect a power supply and input/output boards to a motherboard.
2. Description of the Related Art
Though the computer industry has, over the years, been an area of innovation, improvements are desired in quick connection and disconnection of components of the computer system to increase accessibility to components of the computer system for additions, upgrades, repairs, maintenance and service.
Because of the desire to expand or add on to the features of a computer system and replace components with upgrades, such as more powerful microprocessors, and the need for repairs and maintenance service to the computer system, either by the user or a service center, quick accessibility of computer components have remained a concern. U.S. Pat. No. 5,491,611, assigned to the assignee of the present invention, proposes a computer system having a quick connect cover having a user panel and a service panel for access to circuit boards, power supply and drive units, such as floppy disk drives, hard drives and tape drives. U.S. Pat. No. 5,653,518 to Thomas T. Hardt, assigned to the assignee of the present invention, proposes quick release rail members for a computer drive unit with an arm including a detent movable relative to a slot in the computer frame. U.S. Pat. No. 5,491,611 and U.S. Pat. No. 5,653,518, are incorporated herein by reference for all purposes.
In the past, Compaq Computer Corporation of Houston, Tex., has addressed these concerns by manufacturing computer systems with a motherboard having a microprocessor positioned on a tray that is slidable relative to the frame of the computer housing. Additionally, Compaq Computer Corporation has manufactured a frame having a track member so that a tray having electronic components can be removably positioned with the frame but the electronic components were not automatically connected with a motherboard, or any other board, while positioning the tray in the frame track. Similarly, Compaq Computer Corporation has manufactured a drive tray that is pivotably attached to the frame of a computer housing. The drive tray, that holds a floppy disc drive and a hard drive, pivots upwardly approximately 45.degree. to provide access to the drives. However, the drive tray is not positioned over a motherboard having a microprocessor, or any other printed circuit board and does not automatically electrically connect to the motherboard.
Therefore, it would be desirable to provide a system for aligned quick electrical disconnect and connect of electronic components with a motherboard. In particular, it would be desirable to have an aligned quick electrical connect of electronic components in a tray where upon moving the tray from the motherboard access position to an operating position, the electronic components in the tray are automatically electrically connected with the motherboard.

Aligned pivoting power supply tray and guided input/output tray for connection of the power supply and input/output to the computer motherboard


Discrimination is effected as to which of low-pressure and high-pressure conditions the pressure of fuel to be fed to a fuel injection valve is in. If in the low-pressure condition, the fuel injection pulse widths are corrected by assuming that the fuel pressure is a predetermined reference pressure, since the detection errors of a fuel pressure sensor are large. If in the high-pressure condition, the fuel injection pulse widths are corrected based on an actual fuel pressure detected by the fuel pressure sensor.

1. Field of the Invention
This invention relates to apparatus and method for controlling fuel injection of a direct injection gasoline internal combustion engine, and particularly to a correction control for injection pulse widths during an increasing change of fuel pressure just after starting of the engine.
2. Related Art of the Invention
There has been known a direct injection internal combustion engine in which a fuel is directly injected into a combustion chamber.
In such a direct injection internal combustion engine, the fuel feeding system comprises an engine-driven high-pressure fuel pump for feeding fuel to a fuel injection valve, an electric low-pressure fuel pump for feeding fuel to the high-pressure fuel pump, a low-pressure pressure regulator for regulating a pressure within a low pressure fuel system between the low-pressure fuel pump and high-pressure fuel pump to a predetermined low pressure, and a high-pressure pressure regulator for regulating a pressure within a high pressure fuel system on a downstream side of the high-pressure fuel pump to a predetermined high pressure (such as disclosed in Japanese Unexamined Patent Publication No. 7-77119).
If a pressure of fuel to be fed to the fuel injection valve (hereinafter called "fuel pressure") deviates from a desired pressure, the quantity of fuel to be actually injected into the fuel injection valve changes with respect to pulse widths of an injection pulse signal supplied to the fuel injection valve (hereinafter called "fuel injection pulse width"), resulting in deterioration of precision in air fuel ratio control. Thus, it is required to provide a sensor for detecting the fuel pressure to thereby correct the fuel injection pulse widths in response to a fuel pressure detected by such a fuel pressure sensor.
Unfortunately, as general characteristics of sensors for detecting fuel pressure, the error ratios become larger as the fuel pressure decreases. As a result, the errors in correcting the fuel injection pulse widths become larger during a low pressure state just after starting. Thus, the precision in air-fuel ratio control may be rather deteriorated, if the fuel injection pulse widths are corrected based on the detected result of the fuel pressure under such a condition.

Apparatus and method for controlling fuel injection of direct injection gasoline internal combustion engine


A human-powered vehicle component includes an input device, to which first information related to at least one of a human-powered vehicle, a rider of the human-powered vehicle, and environment of the human-powered vehicle is input. The human-powered vehicle component further comprises an electric actuator and an artificial intelligence processor configured to generate second information for controlling the electric actuator in accordance with the first information input to the input device.

The present disclosure relates to a human-powered vehicle component, a mobile electronic device, and human-powered vehicle equipment.
Patent document 1 discloses an example of a human-powered vehicle component. The human-powered vehicle component executes various calculations in accordance with an output of a detector provided on the human-powered vehicle.
Patent Document 1: Japanese Laid-Open Patent Publication No. 2012-144061

This patent is subject to a terminal disclaimer.

Human-powered vehicle component, mobile electronic device, and equipment for human-powered vehicle


There is provided a printer including: an ink-jet head; a first rotatable body; a first attaching mechanism attaching a printing medium to the first rotatable body; a separating mechanism separating the printing medium from the first rotatable body; and a control mechanism. In the printer, first to forth routes are formed. In transporting the printing medium, the control mechanism causes the printing medium having been subjected to printing on a first surface by the ink-jet head to pass through the first route, next to pass through the second route and the third route at least once, thereafter to separate from the first rotatable body, and further to pass through the fourth route to be reversed.

1. Field of the Invention
The present invention relates to a printer capable of printing on both surfaces of a printing medium.
2. Description of the Related Art
Conventionally, there has been known a double-sided printer that includes a mechanism turning a printing medium such as a printing paper upside down and is capable of printing on one surface of the printing medium and thereafter printing on the other surface by turning the printing medium upside down. For example, as described in Japanese Patent Application Laid-open No. 2001-31309, there has been known a printer that prints on one surface (front surface) of a printing paper by a printing head, thereafter turns the printing paper upside down by a switchback mechanism, then feeds the printing paper to the printing head again, and prints on the other surface (rear surface) of the printing paper.
As described in Japanese Patent Application Laid-open No. 2001-31309, the conventional double-sided printer prints on the front surface of the printing medium by the printing head, immediately thereafter, turns the printing medium upside down by the switchback mechanism or the like, and feeds the printing medium to the printing head again to print on the rear surface. However, especially when the printing head is an inkjet head, if the printing medium is turned upside down immediately after the printing on the front surface of the printing medium, the printing medium is turned upside down in a state where ink on the front surface is not completely dried, which leads to a risk that the printing on the front surface gets dirty when it comes into contact with a roller or the like.


Disclosed herein is a chip-type network resistor characterized in that resistance layers are formed between a common electrode extending across an insulative substrate and each of a plurality of separate electrodes disposed in the opposite sides of the insulative substrate used to support the common electrode, and overcoat layers are provided to cover the resistance layers and positioned to expose the common electrode, whereby the plating process is applied to the common electrode and the separate electrodes.

1. Field of the Invention
The present invention relates to a chip-type network resistor suitable for high density wiring.
2. Description of the Related Art
There has recently been used a chip-type network resistor shown in FIG. 3 as an alternative to individual chip resistors mounted side by side for wiring.
In the same drawing, separate electrodes 2 are formed on the opposite sides of an insulative substrate 1 made of ceramic by printing four areas of silver paste (or silver/palladium paste) on one of both sides of the insulative substrate 1, i.e., eight areas in total on both sides thereof. Each of resistance layers 3 is formed by printing on a position for connecting between the separate electrodes 2, 2 set in pair on the insulative substrate 1. Then, these resistance layers 3 are subjected to primary coating with glass material or the like, and thereafter trimming grooves (not shown) are defined in the resistance layers 3 by a means such as laser trimming, thereby adjusting the resistance values of the resistance layers 3. After a trimming process has been made, the so-adjusted resistance layers 3 are covered with an overcoat layer 4, as secondary coating, comprised of glass material or the like. After the overcoat layer 4 has been formed thereon, a nickel plating process for preventing silver from being excessively consumed and a solder plating process for ensuring wettability by solder are successively applied to the respective separate electrodes 2. However, since the plating material does not adhere to each of the resistance layers 3 which have been covered with the overcoat layer 4 at the time of such a plating step, there is no possibility of variations in preset resistance values, and moisture-proof characteristics are kept satisfactory.
If such a chip-type network resistor is used, a plurality of chip-type resistors is equivalently mounted as a single unit by simply mounting one chip-type network resistor, thereby greatly improving the workability. When the intervals defined between the adjacent resistance layers 3 on the insulative substrate 1 are reduced, the chip-type network resistor can be mounted even on a high-density type printed-wiring board in which the pitch between adjacent patterns is narrow.
In recent years, there have widely been used, as printed-wiring boards, those subjected to high density increasingly and in which the pitch between adjacent patterns is set to be narrowest. Thus, the chip-type network resistor of the above-described type is not suitable in many cases. In order to permit higher-density wiring or mounting, there has been proposed, as shown in FIG. 4, a chip-type network resistor of a type in which a plurality of resistance layers 3 each mounted between a common electrode 5 extending across an insulative substrate 1 and each of separate electrodes 2 are disposed on both sides of the common electrode 5 in a zigzag manner, and the thus-disposed resistance layers 3 are covered with an overcoat layer 4. However, this type of chip-type network resistor has the problem that the impedance of the common electrode 5 is slightly large and is susceptible to the influence of noise.


Voice stream augmented note taking may be provided. An audio stream associated with at least one speaker may be recorded and converted into text chunks. A text entry may be received from a user, such as in an electronic document. The text entry may be compared to the text chunks to identify matches, and the matching text chunks may be displayed to the user for selection.

Voice stream augmented note taking is a process for capturing information from an audio recording and associating that information with user-generated content. In some situations, it can be helpful for a user to be provided with additional information when the user is reviewing notes taken. For example, a user may be typing notes during a presentation such as a lecture or a meeting, but may not remember additional details associated with those notes during a later review. Attempts by the note taker to include all those details while listening to the presentation may result in the note taker missing later details as they try to keep up. Conventional systems, such as short hand, stenography, and rapid typing are often difficult to learn and may be impractical for casual conversations.


A dental prostheses modeling system includes a tray having in an upper part thereof a trough for receiving a semi-liquid modeling material or casting material such as plaster of Paris or die stone, the trough having opposed vertical walls in which are formed alternating vertically disposed ribs and grooves for forming complementary shapes in sides of a casting molded in said tray, a base portion of which has in outer walls thereof alternating vertically disposed grooves and ribs, the trough having a frangible base plate which overlies an upwardly concave cavity for receiving liquid die stone after the upper casting has solidified, hardened and been removed, the base plate being broken and removed to uncover an elongated aperture joining the upper trough to the lower cavity enabling the cast to be ejected from the tray, pins fitted into selected portions of the casting base, the casting reinserted into the trough, and the tray inverted to receive liquid die stone which hardens to form a stone base matrix for insertably receiving pins protruding downwardly from portions of the casting, the casting being then removed from the trough in the upper portion of the tray and severed into segments which are releasably re-engageable along with adjacent portions of the casting within the tray, proper registration between segments of the casting being effected by insertable receipt of pins within holes formed in the die stone base during hardening thereof, and engagement between ribs and grooves of the casting segments with complementarily-shaped grooves and ribs in the inner side walls of the upper tray trough.

A. Field of the Invention
The present invention relates to articles and methods used in the fabrication of dental prostheses such as crowns and bridges made of various combinations of metal and ceramic materials and used to overlie or replace imperfect or missing teeth. More particularly, the invention relates to a system for use in fabricating crowns and bridges, the system including an apparatus and method for making from a mold or impression of a patient's teeth, a dental model cast which is formed from solidified liquid die stone poured into the mold. The dental model cast is segmentable into die segments, each of which has both horizontally protruding ribs and grooves for releasably engagement with complementary-shaped grooves and ribs formed in a support tray, and a pin protruding downwardly from the die segment and adjacent segments for receipt within indexing holes formed through a base member matrix formed within the tray, the pin facilitating gripping and manipulating of the die during various fabrication operations performed by a dental technician.
B. Description of Background Art
A dental procedure which is routinely used to restore function and aesthetic appearance to a person's mouth after a tooth has become broken, structurally degraded by disease or removed entirely, consists of capping or replacing the tooth with a prosthetic restoration, such as a crown or bridge. One form of dental prosthesis or artificial tooth replacement which is widely used consists of a cap or crown for a tooth that is made of a resin, molded ceramic material, a precious metal such as gold or an alloy thereof, or a layered combination of metals and resins or ceramic materials. Various combinations of the foregoing materials provide tooth restorations which possess requisite durability and aesthetic appearance, as well as sufficient hardness to be suitable for chewing foods. The process of fabricating tooth restorations has been in use for a substantially long time, and includes a well-defined sequence of steps, which are briefly summarized below.
According to a first step in existing methods of fabricating dental prostheses or artificial replacement teeth, a negative impression mold is made of a group of a patient's teeth, including missing, broken or decayed teeth which are to be repaired or replaced and teeth which are laterally adjacent to the defective teeth. Such impressions are typically made by positioning within the mouth of a patient, adjacent to teeth to be restored, a shallow curved tray which contains a polymer material such as alginate, elastomer, hydrocolloid or a polyether, which is capable of being indented by a tooth, and forming and retaining a stable impression of the tooth. The impression material is initially in the form of a putty, slurry or thick paste which rapidly solidifies at ambient room temperature and pressure. The tray is inserted into a patient's mouth positioned generally horizontally and in vertical alignment with a subject area of the teeth, and the patient bites down on the tray, or the tray is pressed into contact with the teeth, thus pressing the teeth into the viscous semi-liquid mold impression material held by the tray. After a few minutes, the mold impression material solidifies into a rubber-like elastomeric state which has formed therein precise negative impressions of teeth in a subject area of the patient's mouth.
Dental impression trays for use as described above are available in a variety of styles. One type tray has an arcuately curved plan-view shape which is similar to the curved arrangement of teeth in the jaw. The curved arc length of the tray approximates that of about one half an upper or lower jaw and hence is referred to as a quadrant tray. A flat, paddle-like handle protruding horizontally outwards from one end of the tray is usually provided, to facilitate inserting and removing the tray from a patient's mouth. A typical quadrant tray has on one side thereof a curved trough for receiving impression mold material, may be used to make impressions of upper or lower jaw quadrants and is referred to as a standard quadrant or single-bite tray.
Since an important structural feature of a dental prosthesis is proper registration and biting contact or occlusion between the prosthesis and teeth located in the opposing jaw, it is desirable to make an impression of occluding teeth in the opposing jaw in addition to the impression made of teeth that are to be restored. Therefore, it has been a trend in dentistry for the dental professional to simultaneously make impressions of teeth that are to be restored and occluding teeth in the opposing jaw. A convenient method for simultaneously making restorative and opposing impressions utilizes a tray which has a plan-view shape similar to that of a single-bite, standard quadrant impression tray, but which has upper and lower troughs for holding mold impression material in both upper and lower sides of the tray. Both the upper and lower troughs of these "double-bite" or "triple" trays are filled with viscous impression material and inserted into the patient's mouth between the upper and lower jaws in vertical alignment with teeth to be restored, whereupon the patient bites down on the tray, simultaneously forming impressions of upper and lower teeth.
After impressions of teeth have been made in the manner described above, and the mold impression material solidified, the tray holding solidified mold impression material containing negative impressions of a patient's teeth is removed. The mold, typically referred to as an "impression," is then used to make positive replicas of teeth by pouring a semi-liquid molding material such as plaster of Paris, or die stone, into the depressions formed in the impression, which are accurate negative replicas of the teeth. After the die stone has solidified into a hard stone-like casting, or cast, the cast is removed from the impression, a task which is facilitated by the fact that the impression material is elastomeric, enabling it to be readily peeled away from the die. The casting is then used to fabricate one or more tooth restorations or prostheses in the following manner.
A master cast, i.e., a cast which includes replicas of teeth which are to be restored, is partitioned into one or more individual segments and/or dies, each consisting of a replica of a tooth which is to be replaced by or fitted with a dental prosthesis. Partitioning of a master cast into die segments is typically accomplished by making parallel vertical saw cuts through the master cast. The individual die segment or segments are then used as three-dimensional models or templates for fabricating crowns or bridges. In general, the exterior surfaces of the prosthesis cannot simply replicate those of the die segments. This is because the occlusal surface of the prosthetic tooth restoration, and to a lesser extent, lateral surfaces of the restoration, may require contouring which is different from that of the die segment. For example, the process of fabricating crowns for diseased or damaged teeth entails grinding decayed or broken outer portions of the tooth down until a stump of healthy dentin or enamel remains, a procedure referred to as "prepping" the tooth. Obviously, a crown which is fabricated to fit onto a stump must have a substantially different, tooth-like shape rather than a stump-like shape.
From the foregoing discussion, it can be appreciated that the fabrication of dental prosthesis models from die segments is a labor-intensive task requiring the skills of a prosthodontist or skilled, experienced, dental lab technician. Fabrication of prosthetic dental models typically requires that die segments be contoured by applying a workable material to exterior portions of the die segment, and sculpting the material. The die segment is then replaced into the space in the master cast from which it has been removed, and proper occlusion of the sculpted prosthetic model confirmed by bringing model teeth replicated in the opposing cast into bite-like contacting registration with the occlusal surfaces of the prosthetic model and adjacent teeth replicas of the master cast. This registration check, generally must be repeated several times, to ensure proper sculpting of the occlusal surface of the die segment which serves as a model for fabricating a dental prosthesis. Moreover, it is essential that the biting contact or occlusion between the teeth replicated by the master cast and opposing cast precisely duplicate occlusion of the patient's teeth. Therefore, the master cast and opposing cast must be precisely and repetitively pivotably contacted against one another in a motion which simulates the opening and closing of a patient's jaws. Upon satisfactory completion of sculpting of lateral and occlusal surfaces of die segments, the die segment is used as a mold pattern for casting a metal, ceramic, or metal-ceramic composite dental prosthesis.
One type of device which is used to pivotably register master and opposing dental models or arches is referred as an articulator. For example, Cho, U.S. Pat. No. 6,019,601, Tray Modeling System With Articulator Assembly And Ejection Mechanism For Producing A Dental Model, discloses a pair of trays which are removably and pivotably joined together by detachable hinge members. Each tray has formed upon an upper surface thereof a rectangularly-shaped, trough-like depression, the longest inner facing side walls of the trough having formed therein alternating vertically disposed ribs and grooves. The device is used by pouring a thick paste of liquid die stone slurry into both a dental impression and the tray, and inverting the impression to enable the liquid die stone slurries in the impression and tray to commingle. When the die stone has solidified, the impression is removed from the cast, and the cast removed from the tray by punching through a frangible base panel in the tray, forcing the cast vertically outwards from the trough. The cast is then sawed into segments, which are returnable to precisely repeatable locations within the trough because of the interlocking ribs and grooves formed in the vertical walls of the cast by die stone solidifying in the grooves and ribs, respectively, of the trough side walls, during hardening of the die stone. In the same manner, an opposing cast is made in the other tray, and the trays pivoted towards one another on the hinge pins to precisely and repeatedly bring the occlusal surfaces of the opposing cast and master cast into occlusal registration.
The Cho modeling system and articulator provides a convenient means for preparing and articulating dental models. However, some dental technicians prefer working with die segments which have an elongated cylindrical pin protruding from the base of the die segment. In modeling systems using pinned die segments, the pins are insertably received in holes provided in the base of a tray, and are used to reproducibly position or relate individual die segments to adjacent portions of the master cast. Moreover, a pin protruding from a die segment provides a convenient handle which enables the dental technician to hold a die segment while working on it, including rotating the die segment a full 360 degrees by twisting the die segment pin between the thumb and forefinger of the dental technician. Thus, Sim, U.S. Pat. No. 6,402,513, Dental Model Articulator, discloses a dental model articulator which has pinned die segments. The dental model articulator disclosed in Sim utilizes a top insert which has front and rear upwardly protruding ridges that have grooved upper surfaces. The insert is detachably supported on a lower frame. To pour a master cast of a dental impression, a middle frame must be fastened to a lower frame and around the top insert by engaging slots on left and right sides of the middle frame with retentive latches which protrude upwards from the lower frame, on left and right sides of an upper opening in the lower frame which holds the top insert. According to the disclosure of Sim, the middle frame is discarded after completion of a second pour of liquid die stone through a bottom opening of lower frame, to form a perforated matrix for receipt of pins installed in the base of the first impression casting. The grooved insert is discarded after the first pour.
The present invention was conceived of to provide an improved dental prostheses modeling system which utilizes die segments that each have ribs and grooves which enable repeatable removal from and re-registration of segments within a cast. Each die, segment also has a downwardly protruding pin for facilitating both manipulation of the die segment and reinsertion into the cast, the die segment being quickly and easily fabricated using a sparse number of components and steps.

Pin-tray dental prostheses modeling system


An incline press exercise apparatus is provided. The incline press apparatus includes a selectable weight mechanism and a support member which pivotably supports a pair of four-bar linkage mechanisms. The four-bar linkage mechanisms are pivotably mounted at their rearward ends about axes which are disposed at an angle relative to a horizontal plane, i.e. are tilted relative to vertical, such that a pair of elongated bars of the four-bar linkage mechanisms travel in planes which are tilted relative to vertical. The tilted planes through which the four-bar linkage mechanisms travel enable the handles to travel along a slightly curvilinear downwardly diverging path which simulates as natural a human musculoskeletal pushing motion as possible.

1. Field of the Invention
The present invention relates to an apparati for exercising regions of the upper body, and more particularly to an improved incline press exercise machine.
2. Background of the Invention
A variety of exercise machines which utilize resistance or strength training have become very popular in recent years. Such strength machines are often used in place of conventional free weights to exercise a variety of muscles within the human body. Most strength machines are designed with the goal of optimizing resistance training benefits to the user by combining adjustable weight resistance with ease of use, while also attempting to maintain proper biomechanical alignment of the user's joints.
While such machines offer convenience and other benefits to the user in comparison to free weights, conventional designs typically include a frame superstructure for providing symmetrical balance and support for various levers and weight components of the machines. Such conventional frame superstructures generally result in machines that are oversized in height, width, and architecture. In addition, many of such conventional machines may be inconvenient to users performing more than one repetition of an exercise with varying weights, as the user is generally required to be physically removed from the machine in order to place weights on, or otherwise select the desired weight force before performing each set.
Another limitation found in conventional strength machines utilizing selectable weights is the inability of the user to perform high velocity exercises. In such conventional machines the weights have inertial problems at higher speeds which can result in inconsistent resistance through a complete range of motion, therefore, users are encouraged to perform the exercises slowly. Training at lower velocities produces greater increases in muscular force at slow speeds for the user. Therefore, low velocity training only improves an individual's capabilities at slower speeds. In contrast, training at higher contractal velocities produces increases in an individual's muscular force at all speeds of contraction at and below the training velocity. Therefore, high velocity training improves an individual's functional capabilities at normal contractal velocities, i.e. velocities utilized for activities such as golfing and tennis which are more likely to be a part of every day living. Although there are many forms of strength training which allow for higher velocity training, the resistance mechanisms of such equipment generally do not include selectable weights, these devices do not utilize selectable weights as part of their resistance mechanism, and many users prefer training with selectable weights as opposed to other forms of resistance training, for example, resistance bands.
Conventional resistance equipment may also be limited by designs that prevent users from maintaining the proper biomechanical alignment of joints through a complete range of motion. A variety of machines have been proposed to improve the range of motion of the user, in order to make the exercise performed through the range more effective. Such machines are disclosed in, but not limited to, U.S. Pat. Nos. 5,437,589 and 5,273,504. However, the equipment disclosed in such references does not consistently provide proper biomechanical alignment of the user's joints through the complete range of motion.
Therefore, a need exists in the field of resistance training for selectable weight equipment that allows users to maintain the proper biomechanical alignment of joints through a complete range of motion, while performing exercises at high contractal velocities.

Incline press apparatus for exercising regions of the upper body


A portable cigar ashtray includes a cup-shaped base portion having a closed bottom, a side wall extending upwardly from the closed bottom, and an open top. A resting platform is disposed inside the cup-shaped base portion and spaced from the closed bottom. A retaining assembly is disposed near an upper end of the cup-shaped base portion and includes a retaining ring and a nub holder.

People that smoke cigarettes, cigars, and pipes typically use ashtrays both to rest or hold the cigarette, cigar, or pipe and to catch and hold ash. Traditionally, ashtrays were provided in cars and a variety of public places, but have become less available over time. Additionally, traditional ashtrays, even when provided, are generally not properly sized or shaped to hold a cigar. Unlike cigarettes, a cigar takes an extended period of time to smoke and the smoker may wish to rest the cigar on or in an ashtray for an extended period and for the cigar to be supported in a stable position.


Optical storage media often contain data structures for a menu suitable for selection of a title, a chapter, a parameter or others. Such menus usually comprise a number of buttons to be displayed, with each button having a state. Possible states of buttons are “unselected”, “selected” or “activated”. According to the invention, the representation of a menu button may vary, depending on its state. An image or an image sequence, e.g. cartoon, may be associated to a buttons state, providing user animation. Further, a sound or sound sequence, e.g. melody or click, may be associated to a buttons state, and may be played back when the button enters this state. A data structure is disclosed which allows storage of such menu data e.g. on a Blu-ray disc.

Today's optical storage media formats are capable of supporting visual menus, e.g. for content management or control functions. Applications of such visual menus are the selection of one out of multiple titles on the disc, the selection of a chapter within a title, and others. From the user perspective, such menus consist of a number of buttons shown on the display. The user may navigate within the menu, e.g. by pushing the up, down, left and right buttons on his remote control to select a menu button, and may activate a menu button through some kind of "OK" button on the remote control. An indicator, usually a highlight or an arrow, may provide feedback to the user, showing which button is currently selected or activated. A menu button may have one of the states "normal", "selected" or "activated". However, known DVD menus are rather limited concerning extra features, since they contain only static visual buttons.
Further, a subtitling specification contained in the document "ETS 300 743: Digital Video Broadcasting (DVB); Subtitling System" (DVB-ST), provided by the European Telecommunication Standardization Institute (ETSI), is known for embedding subtitles into video sequences.

Method for representing animated menu buttons


The present invention relates generally to adsorbents for use in pressure swing adsorption (PSA) prepurification processes. The invention more particularly relates to the design of adsorbent zones to be used in PSA prepurification processes that are expected to provide for extensions in PSA cycle time, thereby reducing blowdown loss and operating costs associated with the process. One particular embodiment of the present invention includes a first adsorption zone containing activated alumina and a second adsorption zone of an alumina-zeolite mixture or composite adsorbent in which the volume of the first zone does not exceed 50% of the total volume of the first and second zone.

Gas purification, more specifically air prepurification, represents a class of adsorption separation processes where multiple adsorbents can be applied to improve process performance. The operation of cryogenic air separation plants requires large quantities of pretreated air. To prevent freezing and plugging of the primary heat exchanger, the concentration in the pretreated air of contaminants or impurities such as CO2 and H2O are required to be lowered to less than 1 ppm. In addition, the concentration of light hydrocarbons such as acetylene which have a low solubility in cryogenic liquids must be kept very low, typically less than 1 ppb, to prevent accumulation within the cryogenic distillation system. Nitrogen oxides (e.g., N2O) also need to be removed to the sub ppm level.
Removal of contaminants or impurities can usually be accomplished by an adsorption process employing two or more vessels containing one or more adsorbents selective towards the impurities. When an adsorption bed is saturated with impurities, the bed needs to be regenerated by either one or a combination of two different general methods: pressure swing adsorption (PSA), during which a change in pressure is utilized to regenerate the sorbent, or temperature swing adsorption (TSA), during which the impurities are desorbed by using a thermal driving force such as a heated purge gas. The TSA process may also optionally superimpose a pressure swing to enhance its regeneration capability and reduce its purge requirement. The TSA process usually requires a much lower amount of purge flow relative to the PSA process and affords a longer cycle time, typically in the range of about 4-10 hours. On the other hand, the PSA process typically requires a greater amount of purge flow and has a much shorter cycle time, on the order of 10-50 minutes. The PSA process, however, can operate with ambient feed temperatures contrary to the TSA process, which typically needs a feed cooled to sub-ambient temperature by means of a refrigeration system. Moreover, there is no requirement for regeneration heat energy in PSA as opposed to TSA.
When there is sufficient waste nitrogen available from a cryogenic air separation plant, the nitrogen can be used as the purge flow gas as it typically contains no impurities and would otherwise be vented. Accordingly, when such nitrogen is available, PSA is therefore usually a preferred option for air prepurification due to its simplicity, lower capital cost as well as lower operating cost.
Notwithstanding the advantages of the PSA process compared to the TSA process, PSA processes have been limited in that the adsorbents are typically not completely regenerated at the completion of the purge step. Consequently, the bed dynamic capacity is less than it would be for a TSA process. As a result, the PSA process is typically run for short cycle times which thus necessitates that the bed(s) undergo blowdown and repressurization at fairly frequent intervals. During the blowdown step, there is a noticeable loss of air trapped within the void spaces of the vessel(s) and piping as well as the air adsorbed on the adsorbents therein. This collective air loss, referred to by various terms such as blowdown loss, vent loss or bed switch loss, can represent a significant energy waste as the air is compressed but not utilized for air separation downstream of the prepurifier. Reducing the blowdown loss can provide significant operating cost savings in terms of reduced compression power.
There are other disadvantages associated with frequent bed switches in a PSA cycle. For example, in a dual bed PSA process, the repressurization phase can cause upsets in the flow of purified air to the cryogenic distillation columns downstream of the prepurifier. Such frequent flow fluctuations can disturb the dynamics of the distillation process, thus resulting in lower efficiency for air separation in addition to causing a variation in the product purity.
Most prior art techniques to reduce or minimize the blowdown loss in a PSA process have focused on the reduction of the co-adsorption of the bulk components of air, namely O2 and N2, on a per cycle basis. Such techniques prompt the selection of an adsorbent configuration with a larger proportion of a weak adsorbent such as activated alumina which has very low capacity for O2 and N2, and a relatively smaller proportion of the stronger adsorbent, such as a molecular sieve.
An alternative approach to lower the power requirement of the PSA process is to reduce the frequency of the blowdown or bed switch loss mentioned above. This can be accomplished by extending the cycle time for which the bed is kept online prior to being switched to regeneration. Because the adsorbents and the bed configurations described in the prior art typically afford fairly modest dynamic capacities for impurity removal, an increase in cycle time would require either reducing the feed flow significantly at a fixed bed size, or require a significant increase in the bed size at a fixed feed flow rate. Both of these options can have adverse consequences on the capital and operating costs of the PSA prepurification process.
K. Chihara and M. Suzuki, "Simulation of Nonisothermal Pressure Swing Adsorption," Journal of Chemical Engineering of Japan, Vol. 16, No. 1, pg. 53-61 (1983) describe a computer simulation study of a non-isothermal PSA case study involving the drying of air using a single layer bed composed of either activated alumina or silica gel. An optimization of various process parameters such as bed length, cycle time and purge to feed ratio was presented. It is suggested from this work that an increase in adsorption cycle time would either require a longer bed length or a higher purge to feed ratio to maintain the product purity at a desired level.
German Patent Application DE 3,045,451 A1 (1981) describes a PSA process in which air is passed through a first stage having 13× zeolite to remove CO2 and H2O in their high concentration zones, and then through a second stage having activated alumina to remove the remaining CO2 and H2O in their low concentration zones.
U.S. Pat. No. 4,711,645 to Kumar proposes a PSA process with improved energy savings relative to conventional TSA processes. The PSA process includes feeding air through an initial layer of alumina for H2O removal followed by a bed of zeolite for CO2 and residual H2O removal. The lower heat of adsorption of H2O in alumina compared to that of water in zeolite reportedly results in a smaller temperature rise and improves the bed capacity for CO2 removal in the downstream layer of zeolite.
U.S. Pat. No. 5,232,474 to Jain relates to a PSA process in which an alumina layer is reportedly designed to remove at least 75 mole percent of the CO2 present in a feed stream containing at least 250 ppm of CO2. The feed may optionally be passed through a second adsorption zone containing a zeolite such as 13× to remove residual CO2 and hydrocarbons. In such layered configurations, the alumina occupies more than 80% of the total bed volume.
U.S. Pat. No. 5,769,928 to Leavitt discusses a PSA bed composed of at least two discrete layers of adsorbents, at least one of the adsorbents being comparatively strong and at least another of the adsorbents being comparatively weak with respect to the adsorption of water and other contaminants. More specifically, the patent relates to the use of a comparatively weaker adsorbent such as activated alumina, followed by a stronger adsorbent such as NaY. This configuration is said to ensure a consistent breakthrough of CO2 ahead of the C2H2 front, providing improved plant safety.
U.S. Pat. No. 5,779,767 to Golden et al. relates to a mixture of adsorbent composed of activated alumina (or an alkali-modified alumina) and a zeolite without maintaining the two adsorbents in separate beds or layers for the removal of various air impurities. Such a bed design reportedly has a high working capacity for CO2 to reduce bed size. In addition, the adsorbents are said to have high reversible capacity for acetylene, water and nitrogen oxides.
The use of an activated alumina and zeolite composite or a homogeneous mixture formed by blending beads of activated alumina and zeolite for the removal of CO2 from feed streams is also disclosed in Jain, et al., EP 0 904 825 A2. H2O in the feed may be removed in the mixed alumina-zeolite layer itself or by using a preliminary layer containing a desiccant such as activated alumina or silica gel.
Ackley et al., in U.S. Pat. No. 6,027,548, propose a PSA prepurifier bed composed of a mixture or a composite of at least two adsorbents, one of which is comparatively strong (e.g., NaY or NaX) and the other which is comparatively weak (e.g., activated alumina). Such a bed configuration is said to preferentially adsorb acetylene or C3-C8 hydrocarbons over CO2 and is self-cleaning with respect to these contaminants at a lower purge than that required by 13× zeolite. A preferred embodiment is to utilize activated alumina near the feed end and the mixed adsorbent near the product end of the bed.
The removal of CO2 and H2O from air using a layered bed of y-alumina and 13× zeolite using numerical computer simulations is discussed in Rege et al., "Air-Prepurification by Pressure Swing Adsorption Using Single/Layered Beds," Chemical Engineering Science, Vol. 56 No. 8, pg. 2745-2759 (2001). At certain fixed process conditions such as constant bed length, purge to feed ratio, feed flow and cycle time, the relative proportion of alumina and 13× zeolite layer heights in the bed were varied to reportedly optimize the design. The authors concluded that a minimum impurity concentration results when the ratio of alumina to the zeolite is 7:3.
Given the growing cost of energy worldwide, there is an increasing need to reduce power and increase the operational efficiency of the PSA prepurification process. In view of the teachings of the prior art, it would therefore be desirable to provide an adsorbent zone configuration suitable for use in a PSA prepurifier that allows for extension in PSA cycle times and that can lower blowdown loss and reduce operating costs associated therewith.

Adsorbents for pressure swing adsorption systems and methods of use therefor


The present invention provides a vaccine for inducing an immune response in mammal to a specific antigen, where the vaccine comprises a unit dose of a binary toxin protective antigen and the antigen, which is bound to a binary toxin protective antigen binding protein. In one embodiment the vaccine is comprised of an anthrax protective antigen and the antigen bound to anthrax protective antigen binding protein. The present invention also provides a method of immunizing a mammal against an antigen using the vaccine, and a method of inducing antigen-presenting mammalian cells to present specific antigens via the MHC class I processing pathway.

The mammalian system reacts to invading pathogens by mounting two broad defenses: the cell-mediated response and the humoral response. Viral and other intracellular infections are controlled primarily by the cell-mediated immune system. This control is achieved through recognition of foreign antigen displayed on the cell surface of an infected cell. The present invention describes a vaccine that stimulates the cell-mediated immune system and a method for immunizing mammals. The present invention also describes a method for inducing antigen-presenting cells to present specific antigens using the MHC class I processing pathway.
The cell-mediated immune system responds to endogenous antigen presented by the MHC class I processing pathway. Cells can process foreign proteins found in the cell cytosol and display relevant peptide epitopes using this processing pathway (Harding, in Cellular Proteolytic Systems, pp. 163–180 (1994); Carbone & Bevan, in Fundamental Immunology, pp. 541–567 (Paul, ed., 1989); Townsend & Bodmer, Annu. Rev. Immunol. 7: 601–624 (1989)). The MHC class I processing pathway involves digestion of the antigen by the proteasome complex and transport of the resulting peptides into the endoplasmic reticulum, where they bind to nascent MHC class I molecules (Germain & Margulies, Annu. Rev. Immunol. 11: 403–450 (1993)). Cytotoxic T lymphocytes (CTLs) specifically recognize the foreign antigen displayed by the MHC class I molecules and lyse the antigen-presenting cells. A population of memory T cells is also established that can react to presentation of the specific antigen. The cellular immune system is thus primed to swiftly respond to an intracellular infection by a pathogenic organism such as a virus.
The objective for a vaccine that stimulates the cell-mediated immune system is to deliver protein antigen to the cell cytosol for processing and subsequent presentation by MHC class I molecules. Several bacterial toxins including diphtheria toxin (DT), Pseudomonas exotoxin A (PE), pertussis toxin (PT), and the pertussis adenylate cyclase (CYA) have been used in attempts to deliver peptide epitopes to the cell cytosol as internal or amino-terminal fusions (Stenmark et al., J. Cell Biol. 113: 1025–1032 (1991); Donnelly et al., Proc. Natl. Acad. Sci. U.S.A. 90: 3530–3534 (1993); Carbonetti et al., Abstr. Annu. Meet. Am. Soc. Microbiol. 95: 295 (1995); Sebo et al., Infect. Immun. 63: 3851–3857 (1995)). These systems are restricted in their use as potential vaccines because they do not provide access to the MHC I processing pathway for antigen presentation, but instead likely operate through an alternative, less efficient pathway (see Kovacsovics-Bankowski & Rock, Science 267: 243–246 (1995); Rock, Immunology Today 17: 131–137 (1996)).
Surprisingly, the present invention provides antigen access to the MHC class I processing pathway via the anthrax binary toxin system. The Bacillus anthracis binary toxin consists of two distinct proteins (Smith & Stoner, Fed. Proc. 2: 1554–1557 (1967); Leppla, in Bacterial Toxins and Virulence Factors in Disease. Handbook of Natural Toxins, vol 8, pp. 543–572 (Moss et al., eds., 1995)). Protective antigen (PA) combines with lethal factor (LF) to make "lethal toxin" or "anthrax" toxin. (Friedlander, J. Biol. Chem. 261: 7123–7126 (1986); Leppla, Proc. Natl. Acad. Sci. U.S.A. 79, 3162–3166 (1982). In addition to lethal toxin, PA combined with edema factor (EF) makes edema toxin (Friedlander, Leppla, supra).
In this system, PA (83 kDa) binds to a protein receptor on the surface of cells. PA is then cleaved by a cellular protease (furin) and a amino-terminal 20-kDa fragment is released, leaving a 63-kDa fragment, PA63, bound to the cell (Leppla et al., in Molecular Mechanisms of Bacterial Virulence, pp. 127–139 (Kado & Crosa, eds., 1994); Klimpel et al., Proc. Natl. Acad. Sci. U.S.A. 89: 10277–10281 (1992)); Novak et al., J. Biol. Chem. 267: 17186–17193 1992)). PA63 binds to LF and the binary anthrax toxin is then endocytosed and transported into the cell. PA facilitates the delivery of LF from the endosome to the cytosol of the cell (Milne et al., J. Biol. Chem. 269: 20607–20612 (1994); Milne et al., Mol. Microbiol. 15: 661–666 (1995)). LF fusion proteins are also translocated into the cytosol by PA.
Once in the cytosol, in contrast to other binary toxin systems, the anthrax toxin and LF fusion proteins are processed by the MHC class I processing pathway. Cells treated with anthrax toxin fusion proteins are recognized and lysed by antigen specific CTLs. Dependence on processing via the MHC class I pathway was demonstrated by treating antigen-presenting cells with lactacystin, which inhibits proteasome function required for MHC class I processing. Thus, the anthrax toxin system can be used to create vaccines that efficiently stimulate the cell-mediated immune system.
In addition, binary toxins that have similar functional qualities can be used for the present invention. For example, the iota toxin of Clostridium perfringens is a binary toxin homologous to the lethal toxin of B. anthracis. Protein Ib of C. perfringens binds to protein Ia to form the toxin, and protein Ib is involved in cell surface binding and internalization of the toxin (Perelle et al., Infect. Immun., 61: 5147–5156 (1993)). The predicted amino acid sequence of Ib shows 33.9% identity with and 54.4% homology with PA (Perelle, supra).
One advantage of the anthrax system is its ability to accommodate large fusion proteins. Unlike the anthrax system, other bacterial toxin systems are limited in their capacity to deliver large protein antigen to the cell. While peptides are able to stimulate a cell-mediated immune response, whole protein antigens may be better suited for use in an effective vaccine, for two reasons. First, the epitope that is essential for protection in one genetic background may be irrelevant in another. Therefore, it is beneficial for a broadly applied T-cell vaccine to use the full length protein from which the various relevant epitopes are derived. Second, epitopes recognized by CTL are processed from the whole protein by specialized degradative machinery. In certain instances, the processing of the relevant epitopes is dependent on the flanking amino acid sequences (Del Val et al., Cell 66: 1145–1153 (1991)). Because it is currently not possible to accurately predict which epitopes are dependent on their context for proper processing, it is important to deliver the entire antigen to the cell cytosol for optimal processing and presentation. A final drawback to other bacterial toxin systems is that many individuals have already been immunized against the carrier toxin. However, anthrax toxin is not widely used for immunization.
With this invention, the efficient delivery of anthrax fusion proteins to the cytosol can be safely used as a method to intracellularly inoculate living cells with whole protein antigens. These antigens are then displayed by MHC I molecules. This system provides the basis for new, potent vaccines that target the cell-mediated immune system.

Targeting antigens to the MHC class I processing pathway with an anthrax toxin fusion protein

The United States of America as represented by the Department of Health and Human Services


A delay device has series-connected multiplexers in a differential form. First connections of the multiplexers are connected to the output of an upstream multiplexer. Second inputs of the multiplexers are connected to the input connection to which the signal to be delayed can be supplied. A control signal controls the switch setting of one of the multiplexers such that its output is connected to the input of the delay device. The other multiplexers have the other switch setting. In consequence, a specific delay time is set for the delay device. The multiplexers have four current paths which are coupled in pairs. One of the current path pairs can be decoupled from the current source via a transistor.

Such integratable, controllable delay devices are widely used for delaying a clock signal in integrated semiconductor circuits. One particular use of the delay device is in a delay locked loop. Delay locked loops are used to produce clock signals with a predetermined phase angle in digitally processing circuits. For example, in synchronously operated integrated semiconductor memories which operate on the double data rate principle, i.e., DDR SDRAMs (Double Data Rate Synchronous Dynamic Random Access Memories), a delay locked loop (DLL) is used in order to account for internal signal delay times in production, on the output side, of a clock signal, with the data to be emitted being produced in synchronism with an input clock signal supplied at a different point in the integrated circuit.
A delay locked loop compares the clock signal which is supplied to the input side of the delay unit with the delayed clock signal that is produced on the output side, and readjusts the delay as a function of the phase difference until the phase difference is as close to zero as possible. It is particularly important for the clock on the output side to be as stable and free of jitter as possible. For example, the clock on the output side should be influenced as little as possible by fluctuations in the supply voltage and its current delay time setting shall be independent of the drive of the delay unit.

Integratable, controllable delay device, use of a delay device, as well as an integratable multiplexer for use in a delay device


The present invention relates to novel vitamin D receptor related (VDRR) polypeptides, and formulations containing the same. Nucleic acid sequences encoding the VDRR polypeptides, expression vectors containing such sequences and host cells transformed with such expression vectors are also disclosed, as are methods for the expression of the novel VDRR polypeptides of the invention. The invention further relates to VDRR polypeptides for use as medicaments, and use of substances affecting VDRR signal transduction for the manufacture of medicaments for treating metabolic, proliferative or inflammatory conditions. The present invention also relates to methods for identifying clones encoding a VDRR polypeptide, methods for identifying ligands to a VDRR and methods for identifying substances for treatment of conditions affected by a VDRR polypeptide. More specifically, the novel VDRR polypeptide can be the polypeptide designated VDRRγ, which may be regulated by any small chemical molecule similar in structure to known ligands for nuclear receptors.

Nuclear hormone receptors is a large group of conditionally regulated transcription factors. These receptors are activated and regulate target gene expression in response to binding a variety of small chemical molecules (ligands) including steroids, vitamin D3, retinoids, eicosanoides (prostanoids), thyroid hormone and cholesterol derivatives.
A growing number of structurally related receptors have been identified for which no ligands yet have been identified. This group of receptors is referred to as orphan nuclear receptors (ONRs). A review of the ONRs can be found in Enmark et al, Mol. Endo., vol. 10, No. 11 (1996) pp. 1293–1307, which is hereby incorporated by reference. The pivotal importance of a number of ONRs for processes such as metabolic homeostasis, cell differentiation and development have been demonstrated both by biochemical and genetic techniques. In addition, several ONRs have also been implicated as key factors in a variety of common diseases and disorders such as diabetes, obesity, inflammatory conditions and proliferative diseases.
Based on these findings it is generally believed that novel ONRs are going to become potential drug targets for therapeutic invention of common diseases Thus, it is of great importance to identify such receptors.

Nucleic acid encoding vitamin D receptor related polypeptide


Nonmonolithic laser arrays having a plurality of lasing elements mounted on protruding members of a stacked support which includes spacers between the protruding members. The protruding members and spacers are comprised of thermally conductive, but electrically insulative material such as BeO. The conductive layers on the spacers and protruding members assist in providing electrical contact to the lasing elements. The stacked support accurately locates and separates the lasing elements and enables low thermal and electrical crosstalk between the lasing elements.

Many laser based devices such as laser printers and optical memories can be improved by incorporating arrays of independently controlled lasing elements. For example, a laser printer using an array of lasing elements can have higher printing speeds and better spot acuity than a printer using only a single lasing element.
Monolithic laser arrays usually output light at one wavelength. Typically, that wavelength is only variable over a small range. However, in many applications, including color printing, it is desirable to output multiple wavelengths that span a wide range; for example, from the infrared through the visible. In color printing this enables one to match laser characteristics to photoreceptor response windows, or to separate overlapping laser beams after scanning by using dichroic filters. When using an array of lasing elements to output multiple wavelengths it is almost always desirable to have low electrical, optical, and thermal crosstalk between the lasing elements.
As compared to present day monolithic laser arrays, nonmonolithic laser arrays can provide a greater range of laser beam characteristics (such as wavelength, polarization and spot sizes) and lower crosstalk. A nonmonolithic laser array usually consists of a plurality of individual laser diodes mounted on a support. In applications such as laser printing, the output laser beams must be accurately spatially separated. Thus, the lasing elements of the nonmonolithic array must be supported such that accurate positioning of the lasing elements is achieved.
Prior art nonmonolithic semiconductor laser arrays usually arrange their lasing elements along a planar support. Alignment of the lasing elements involves external manipulations of the lasing elements on the support. Such laser arrays suffer from several problems. A first is the difficulty of accurately aligning the laser outputs. A second is that achieving closely spaced laser elements is difficult since edge effects limit the minimum spacing between lasing elements, especially in arrays containing more than two elements.
An alternate approach is to vertically stack the lasing elements. Such an arrangement is used in U.S. Pat. No. 4,716,568, issued Dec. 29, 1987, to make an assembly of monolithic bars of diode laser emitters. In that assembly, the laser emitters in each bar are electrically connected in parallel, while the laser bars are electrically connected in series. Thus current simultaneously passes through all of the laser emitters, thereby precluding the separate addressing of the individual emitters.
Thus, there exists a need for methods and devices that enable close, accurate spacing of lasing elements in a nonmonolithic laser array without excessive thermal, optical, and/or electrical crosstalk. Such methods and devices are even more desirable if they permit the accurate orientation of the lasing elements.

Vertically stacked, accurately positioned diode lasers