The invention relates to an insect cell vector for the production of proteins from the DEAD protein family.

The present invention relates to an insect cell vector for the production of proteins from the DEAD protein family.
The modulation of the RNA structure plays an essential role in cellular processes, such as, for example, in pre-mRNA splicing, in RNA transport or in protein translation, as the cellular RNA is present in the cell in different secondary and tertiary structures and, in addition, a large number of RNA-binding proteins provides for further structuring of the RNA. Proteins from the family of the so-called DEAD box proteins, inter alia, are involved in these modulation processes. The members of this protein superfamily, which as a characteristic contain a number of homologous protein sequences, so-called xe2x80x9cprotein boxesxe2x80x9d, are named after the highly conserved tetrapeptide Asp-Glu-Ala-Asp (residues 21-24 of SEQ ID NO: 23) in the single-letter code D-E-A-D, as a motif. This protein superfamily also includes a number of RNA and DNA helicases.
The characteristic protein sequences of the DEAD proteins are highly conserved in evolution. A schematic representation of the proteins from the DEAD superfamily and its subfamilies as in FIG. 1 shows the similarity between the individual family members (see also Schmid, S. R. and Linder, P. (1992) Molecular Microbiology, 6, 283, No. 3; Fuller-Pace F. V. (1994) Trends in Cell Biology, 4, 271). It is recognized that the DEAD superfamily is divided into various subfamilies, which according to their sequence motif are called DEAH, DEXH or DEAH* subfamily. All family members have an ATP-binding and RNA-binding function and also an ATP hydrolysis and RNA helicase function.
EP-A-0778347 now describes a novel ATP- and nucleic acid-binding protein having putative helicase and ATPase properties, which is assigned to the DEAH subfamily. In addition to the properties mentioned, the RNA helicase described is also connected with the tolerance of certain cells to leflunomide and related compounds and is thus suitable for the production of cell lines which are helpful in cancer, inflammation and apoptosis research and also in the elucidation of mechanisms of action of pharmaceuticals. A further possibility of application of this helicase is the identification of already known substances with respect to possible pharmaceutical properties such as, for example, an anticarcinogenic or antiviral action in a test or assay system. Sufficient amounts of the protein, however, are necessary for the desired types of use of the RNA helicase.
Interestingly, it has not been possible to date to homologously or heterologously express proteins from the DEAD protein superfamily in adequate amounts functionally. In addition to the size of the proteins, many representatives of this family have a molecular mass of 100 kD and above, certain structural motifs appear to inhibit the expression in foreign organisms. In particular, it is suspected of the so-called RS domain, a region of between 50 and 200 amino acids in size, which exhibits a greatly increased number of argenine-serine repetitions (single-letter code RS), that it directly or indirectly complicates protein expression. A direct effect can be caused, for example, by incorrect phosphorylation of the serine residues in this region. Indirectly, overexpression of proteins with this domain can cause toxic effects in the cell, as specific protein-protein interactions are mediated via this protein domain. In the case of heterologous protein overexpression, the native interaction can thus be disturbed or inhibited via RS domains.
The family of RS proteins is a xe2x80x9csubfamilyxe2x80x9d of proteins which is defined by the possession of the RS domain. These proteins are involved in the most different of processes of pre-mRNA splicing. RS domains can mediate protein-protein interactions, influence RNA binding, modulate RNA-RNA annealing and function as subcellular location signals. The relationship between the DEAD box and the RS proteins consists in the fact that both are involved in the modulation of RNA structure and function and therefore many proteins are to be assigned to the protein families.
The RS domain in human RNA helicase according to SEQ ID No. 7 is in the range from about 131 to about 253 and in particular in the range from about 175 to about 216 based on the amino acid position.
It was therefore the object of the present invention to make available a process which makes possible the production by genetic engineering of proteins from the DEAD protein superfamily in large amounts.
It has now surprisingly been found that, in contrast to expression in E. coli or yeast, expression in insect cells is possible in an advantageous manner.
One subject of the present invention is therefore an insect cell vector comprising a nucleic acid coding for a protein from the DEAD protein superfamily. The term xe2x80x9cnucleic acidxe2x80x9d is understood according to the present invention as meaning preferably single- or double-stranded DNA or RNA, in particular double-stranded DNA.
In a preferred embodiment, the coding nucleic acid at the 3xe2x80x2 end of the coding region additionally contains a native 3xe2x80x2-noncoding region, which in preferred embodiments is at least about 50, preferably about 50 to about 450, in particular about 50 to about 400, nucleotides long.
xe2x80x9cNativexe2x80x9d within the meaning of the present invention designates 3xe2x80x2-noncoding nucleic acid regions which originates from the same organism, preferably from the same gene as the coding nucleic acid. If, for example, the nucleic acid codes for a human RNA helicase according to EP-A-0778347, the 3xe2x80x2-noncoding region according to the preferred embodiment likewise originates from human cells, in particular from the gene coding for the designated RNA helicase. The 3xe2x80x2-noncoding region according to SEQ ID No. 10 is preferred.
It is known that the 3xe2x80x2-noncoding region of genes can bind various regulatory proteins or factors. Thus, for example, the so-called xe2x80x9cCleavage and Polyadenylation Specificity Factorxe2x80x9d (CPSF) binds to the noncoding RNA sequence AAUAAA. The CPSF protein consists of a complex of subunits with molecular weights of 160, 100, 73 and 30 kD. A further RNA binding protein is the so-called xe2x80x9cCleavage Stimulation Factorxe2x80x9d (CstF). This protein is a heterotrimer of three subunits of 77, 64 and 50 kD. In addition, there are further RNA binding proteins such as the so-called xe2x80x9cCleavage Factorsxe2x80x9d CF I and CF II and also a poly(A) polymerase. The poly(A) polymerase is a polypeptide with a molecular mass of 83 kD. The polymerase is involved both in the poly(A) tail synthesis and in its cleavage. The extension of the poly(A) tail is strongly stimulated by the so-called xe2x80x9cpoly(A) binding protein IIxe2x80x9d (PABII). Further information and literature references are found in Wahle, E. (1995) Biochemica at Biophysica Acta, 1261, 183. Thus in addition to the AAUAAA binding sequence, Wahle, E. (1995), for example, also describes further consensus motifs such as a GU-rich region having the proposed consensus sequence YGUGUUYY and U-rich elements (see also Proudfoot, N. (1991) Cell, 64, 671-674).
In a preferred embodiment, the present invention therefore relates to 3xe2x80x2-noncoding regions which contains a binding site for the CPSF protein, the CstF protein, the CF I protein, the CF II protein, the poly(A) polymerase and/or the poly(A)-binding protein II (PABII), such as, for example, an AATAAA binding site, ATTAAA binding site, a GT-rich element, in particular a YGTGTTYY element, and/or a T-rich element designated in the form of its cDNA form.
A protein from the DEAD protein superfamily is understood according to the present invention as meaning proteins which have conserved motifs, under which a conserved motif contains the amino acid sequence DEAD, DEAH or DEXH. The proteins preferably contain sequence motifs which are responsible for a nucleic acid-binding activity, a helicase activity and/or an ATPase activity. The proteins in particular contain an RNA helicase and ATPase activity. FIG. 1 and FIG. 2 shows examples of the conserved motifs for the DEAD protein superfamily and the DEAH, DEXH or DEAH* subfamilies.
Within the meaning of the present invention, the term xe2x80x9cDEAD protein superfamilyxe2x80x9d thus includes all proteins which fall within a group according to FIG. 1 or 2. Examples of proteins of this type are described in Fuller-Pace, F. V. (1994), supra, and Schmid, S. R. and Linder, P. (1992), supra. Further preferred proteins are those which impart to cells tolerance to isoxazole derivatives, such as, for example, leflunomide, and compounds related in action, such as, for example, brequinar. Human proteins are particularly preferred, in particular those from Table 1 and the RNA helicase from EP-A-0778347. Within the meaning of the present invention, proteins with a molecular mass of about 100 to about 150 kD, in particular with a molecular mass of about 130 kD, and those with a so-called SR domain, i.e. a region of about 50 to 200 amino acids in size with an increased number of arginine-serine repetitions, are preferably suitable. Within the meaning of the present invention, a nucleic acid coding for the human RNA helicase p135 according to EP 0778347 with the amino acid sequence as in FIG. 3 is particularly suitable.
A further preferred example of a nucleic acid coding for a protein from the DEAH protein subfamily with a native 3xe2x80x2-noncoding region is the cDNA of the human RNA helicase from EP-A-0778347 as in FIG. 5 of the present invention. The 3xe2x80x2-noncoding region of the RNA helicase mentioned according to SEQ ID No. 10 is generally suitable within the meaning of the present invention as a native 3xe2x80x2-noncoding region of human proteins from the DEAD protein superfamily and in particular from the DEAH protein subfamily.
In a preferred embodiment, the vector according to the invention contains regulatory sequences which control the expression of the nucleic acid coding for a protein from the DEAD protein superfamily. All the regulatory sequences known to the person skilled in the art are suitable for this. A promoter of a xe2x80x9clong terminal repeatxe2x80x9d (LTR), in particular of a retroviral LTR or of an LTR of a transposable element according to, for example, U.S. Pat. No. 5,004,687 are particularly suitable. Regulatory sequences from insect viruses, preferably baculoviruses, in particular the promoter of the polyhedrin gene or of the 10K protein (see, for example, EP-B1-0127839) are particularly suitable. In a further preferred embodiment, the native ATG start codon of the nucleic acid coding for a protein from DEAD protein superfamily is replaced by a polyhedrin-ATG translation initiation start site. The nucleic acid according to the present invention is thus a chimeric nucleic acid from insect virus sequences at the 5xe2x80x2 end and heterologous sequences following downstream, the 3xe2x80x2-noncoding part preferably containing sequences native to the heterologous part. This construct according to the invention makes possible a further advantageous increase in expression in insect cells.
In another preferred embodiment, the nucleic acid according to the invention contains a nucleic acid coding for an oligopeptide of at least about 4, preferably of about 6, histidines between the ATG translation initiation start site and the region coding for the protein from the DEAD protein superfamily. After expression of the designated nucleic acid, a fusion protein is obtained from the chosen protein from the DEAD protein superfamily and an N-terminally fused peptide which contains the histidines mentioned. By this means, the protein can be purified in a particularly simple and effective manner, for example, by means of a metal ion-containing chromatography column, such as, for example, a nickel-containing chromatography column, such as Ni-NTA resin-containing chromatography column. xe2x80x9cNTAxe2x80x9d stands for the chelator xe2x80x9cnitrilotriacetic acidxe2x80x9d (Qiagen GmbH, Hilden). Instead of or in addition to the nucleic acid coding for the histidines mentioned, a nucleic acid can also be used which codes for the glutathione S-transferase (Smith, D. B. and Johnson, K. S. 1988) Gene, 67, 31-40). The fusion proteins thus obtained can likewise be purified in a simple manner by means of affinity chromatography and detected by means of a calorimetric test or by means of an immunoassay. A suitable system is, for example, the vector PGEX from Pharmacia, Freiburg as a starting vector.
For the removal of the foreign protein component from the fusion protein mentioned, it is advantageous if the nucleic acid codes for a protease cleavage site. Suitable proteases are, for example, thrombin, or factor Xa. The thrombin cleavage site contains for example, the amino acid sequence Leu-Val-Pro-Arg-Gly-Ser (SEQ ID NO: 1) (see, for example, FIG. 3B). The factor Xa cleavage site contains, for example, the amino acid sequence lle-Glu-Gly-Arg (SEQ ID NO: 2).
A preferred 5xe2x80x2 region of the nucleic acid according to the present invention is, for example, a nucleic acid according to FIG. 3B, which begins in the start codon ATG and ends after the thrombin cleavage site at one of the designated restriction enzyme cleavage sites. The nucleic acid concerned can then be ligated according to generally known processes at the selected restriction enzyme cleavage site. A suitable nucleic acid according to the invention is a nucleic acid comprising the polyhedrin promoter, e.g. according to EP-B1-0 127 839, the nucleic acid p135-NT5C according to SEQ ID No. 12 comprising the polyhedrin-ATG translation initiation start site and a sequence coding for 6 histidines and a nucleic acid according to SEQ ID No. 9 comprising a nucleic acid coding for the RNA helicase p135 and its native 3xe2x80x2-noncoding region.
In a further preferred embodiment, the 5xe2x80x2 region of the nucleic acid according to the invention contains a nucleic acid which codes for a signal sequence, for example an insulin signal sequence, e.g. according to SEQ ID No. 13, in the form of the construct p135-NT5S. This construct also has the advantage that the desired protein can be worked up and purified particularly easily, as on account of the signal sequence it is secreted directly into the culture medium and in the course of this the signal sequence is removed, instead of accumulating the desired protein intracellularly in the insect cells. Further suitable signal sequences are the signal sequence of bombyxin of the silkworm (Congote, L. F. and Li, Q., (1994) Biochem. J., 299, 101-107), signal sequence of the human placental alkaline phosphatase (Mroczkowski, B. S. et al., (1994), J. Biol. Chem., 269, 13522-28), signal sequence of melittin from the honeybee (Mroczkowski, B. S. et al. (1994) J. Biol. Chem., 269, 13522-28; Chai, H. et al. (1993) Biotechnol. Appl. Biochem. (1993) 18, 259-73), signal sequence of the human plasminogen activator (Jarvis, D. L. and Summers, M. D. (1989) Mol. Cell. Biol., 9, 214-23), signal sequences of certain insect cell proteins (WO90/05783) or leader sequences of prokaryotic genes (EP-A1-0 486 170).
Another subject of the present invention is a process for the production of recombinant insect viruses which code for a protein from the DEAD protein superfamily according to the present invention, in which a vector according to the invention is introduced into insect cells together with insect virus wild-type DNA and the resulting recombinant insect viruses are isolated.
A suitable insect virus is, for example, the baculovirus, in particular the Autographa Californica virus. Suitable insect cells are, for example, Spodoptera Frugiperda, Trichoplusia ni, Rachiplusia ou or Galleria Mellonela. The Autographa Californica strains E2, R9, S1 or S3, especially the Autographa Californica strain S3, Spodoptera Frugiperda strain 21 or Trichoplusia ni egg cells are particularly suitable. In addition to the insect cells, ovarian cells of the corresponding insects or their larvae are also suitable. The recombinant insect virus according to the invention is formed in the insect cells by homologous recombination of the vector according to the invention with the insect virus wild type concerned (see, for example, EP-B1-0127839 or U.S. Pat. No. 5,004,687). The recombinant insect virus can then be used for the production of the desired protein.
A further subject of the present invention therefore also relates to a process for the production of a protein from the DEAD protein superfamily, in which a vector according to the invention or a recombinant insect virus according to the invention is introduced into insect cells or insect larvae, the insect cells or larvae are cultured under suitable conditions and the expressed protein is isolated. Preferably, insect cells are infected with recombinant insect virus, the infection period preferably being about 40 to about 90, in particular about 70, hours. The production of a recombinant insect virus or the production of a desired protein in insect cells is carried out by processes generally known to the person skilled in the art, such as are described, for example, in EP-B1-0127839 or U.S. Pat. No. 5,004,687. However, commercially obtainable baculovirus expression systems such as, for example, the Baculo Gold(trademark) transfection kit from Pharmingen or the Bac-to-Bac(trademark) baculovirus expression system from Gibco BRL are also suitable.
It is an advantage of the insect cell expression vectors according to the invention and the processes according to the invention that, surprisingly, relatively large amounts, in general about 300-400 mg per 10 cells, of proteins from the DEAD protein superfamily, in particular of proteins having a molecular mass of  greater than about 100 kD and especially proteins having a so-called SR domain, can be produced.
A further subject of the present invention therefore relates to the use from an insect cell vector according to the invention for the production of a protein from the DEAD protein superfamily. The designated proteins are suitable, for example, for the production of appropriate test systems according to EP-A-0778347 or for the treatment of a disorder as described in EP-A-0778347 or in Ellis N. A. (1997), supra.
The following figures and examples are intended to illustrate the invention in greater detail without restricting it thereto.

Expression vector for the production of dead proteins

Aventis Research and Technologies GmbH and Co.


An article of furniture is formed of a plurality of interconnected modules. Each module comprises a cabinet module in that it is formed by exterior wall members which define an interior storage space therewithin. The module is constructed having one or more slidable drawers or a lid for providing access to the interior storage space. The modules are provided with connecting members, such as male and female fasteners on appropriate side wall members thereof for mutually interconnecting a plurality of such cabinet modules so as to form a desired article of furniture thereby inherently imbuing the article of furniture so formed with cabinet or storage capabilities. The modules can be interconnected in a multitude of different configurations to obtain a variety of different articles of furniture. In one embodiment, the modules are interconnected to form four rectilinearly extending module sub-assemblies to define the periphery of a mattress-receiving area, thus providing a bed having an inherently built-in cabinet or storage capability.

This invention relates generally to articles of furniture and, more particularly, to articles of furniture which are constructed utilizing a plurality of interconnected cabinet modules and to the modules for forming such articles of furniture.
Inhabitants of living areas which provide only a limited amount of usable space such, for example, as apartment dwellers, often find that an inadequate amount of space is available in a given room for various articles of furniture which are necessary are sufficient to meet their needs. Thus, for example, it is not uncommon for an apartment dweller having a bedroom of limited area to find an insufficient amount of space is available for both a bed having comfortable proportions and for cabinet space large enough in which to provide storage for various items, e.g., clothes, sleepwear, toiletries, etc. Under such circumstances, it has been necessary for such an inhabitant to compromise on the size or configuration of the articles of furniture or, in some cases, to do without such article of furniture completely.
Another problem frequently encountered in connection with home furnishings is that an expensive piece of furniture may be purchased having particular dimensions or configurations which render them particularly suitable for use at a certain location within the dwelling. Thus, for example, a person may purchase an expensive cabinet having particular length, height and/or depth dimensions to suit a particular wall or corner of a home. However, it frequently happens that such a person will relocate and find that this piece of furniture is either too large or too small for any appropriate area in his new dwelling. Of course, this is a disadvantage of conventional furniture which may become quite costly to the consumer.
Further, in recent years the cost to the consumer of aesthetically pleasing furniture has drastically increased. Although this fact is applicable equally to furniture of all periods, it is at least as true, if not more applicable, to so-called contemporary and modern furniture. Thus, the cost of such furniture in some cases has risen to the point where the purchase of a large article of furniture is beyond the reach of some if not most consumers.

Article of furniture and modules for forming the same


A method of constructing a concrete block wall of concrete blocks each having one or more vertical openings includes the steps of the layering the blocks one upon the other in positions that generally align the vertical openings to initiate formation of the wall and placing a first reinforcing bar through the aligned openings, the first bar having a diameter, the lower end of the bar being anchored at a lower portion of the wall. A connector is placed on the upper end of the first bar, the connector having upper and lower end portions, a central longitudinal open ended bore and at least one reduced diameter section that extends inwardly from the interior surface of the connector wall. Additional layers of concrete blocks can then be added to the wall in positions that generally align the block openings of the added blocks with the first bar. After these additional layers of blocks have been added, a second reinforcing bar is placed through the aligned block openings of the additional layers of blocks until the second reinforcing bar is inserted into the connector. The connector tightly grips each respective bar to form a frictional engagement of the connector and the bars. The method prevents the extra work of having to lift each block above two bars in the making of the additional block layers.

1. Field of the Invention
The present invention relates to the construction of concrete block walls, and more particularly relates to a reinforcing bar assembly and its method of use for reinforcing concrete block walls. Even more particularly, the present invention relates to an improved connector plus reinforcing bar arrangement for joining two elongated reinforcing bars in, end-to-end orientation, wherein the assembled bars are used in a method of constructing a concrete block wall.
2. General Background of the Invention
In the construction of structures such as walls using concrete blocks, it is known in the industry to reinforce the wall by placing vertically oriented reinforcing bars through aligned vertical openings in the blocks. These vertical openings in the blocks are filled with a concrete "grout" material that surrounds the reinforcing bar.
Presently, as the wall increases in height, additional reinforcing bars must be added to the lowest reinforcing bar that is first placed through vertically aligned openings of the blocks. The present prior art practice is to couple the vertically oriented bars with wire that is wrapped several times around the respective end portions of the two connected bars, and to then continue to build the wall upwardly.
One of the problems encountered in constructing a concrete block wall in this fashion is that a bricklayer must lift each block an extra three or four feet into the air in order to place the vertical opening of the block over an upper reinforcing bar that has been connected to a lower reinforcing bar. Such is required because the bar sections are connected together when the ends of both bars are visible and accessible to the bricklayer.
Connectors for joining reinforcing rods per se are known. One example is the Howlett U.S. Pat. No. 3,415,552, entitled "Splicing Metallic Reinforcing Rods with a Threaded Coupling Sleeve".
The Bengston, et al. U.S. Pat. No. 5,138,808 uses rods in combination with a wall structure. The system includes a plurality of courses of masonry block, each block of which is formed with minimum webbing to minimize heat flow there through. The wall system is forced into a unitary structure through the utilization of post tensioning rods tied to reinforcing rods in the wall footer and extending through the voids in the respective blocks to a top plate position on the top of the wall. The rods are threaded and are post tensioned, the voids contained a polyurethane foam.
A connector for reinforcing rods is the subject of U.S. Pat. No. 1,213,589 issued to Collings. The Collings patent discloses connectors that includes circumferentially spaced, radially extending tongues stamped or cut and bent inwardly of a tube. FIGS. 5 and 7 of the Collings patent show two embodiments of a connector that is said to be useful with reinforcing rods that are used in reinforced concrete construction work, particularly reinforced concrete column construction work.
Various patented constructions relate to the joining of electrical connectors, such as for example the Toquet U.S. Pat. No. 557,037 and the Durant U.S. Pat. No. 2,235,255.
The method of connecting cables the like and articles produced thereby is the subject of the Anderson U.S. Pat. No. 1,959,402.
Other connectors in general are seen in the Bourdon U.S. Pat. No. 1,753,041, entitled "Grommet for Pneumatic Tires" and the Rockne U.S. Pat. No. 2,316,890, entitled "Welding Rod Connector".

Method and apparatus for constructing a concrete block wall


Methods, devices and systems for obtaining heart rate by obtaining apical and non-apical heart rate datum using first and second heart rate monitoring devices. The apical and non-apical heart rate data are input into a heart rate verification module (HRVM) that includes a number of programming instructions for effecting the invention. An apical heart rate measure and non-apical heart rate measure are calculated in the HRVM, and an acceptable heart rate range is generated using the apical heart rate measure. Whether the non-apical heart rate measure is a reliable measure of a true heart rate is identified by determining whether the non-apical heart rate measure falls within or outside the acceptable heart rate range. A split display screen of the HRVM displays the apical heart rate measure, non-apical heart rate measure, and information identifying whether the non-apical heart rate measure falls within or outside the acceptable heart rate range.

1. Field of the Invention
The present invention relates in general to the field of heart monitoring, and more particularly, to devices, methods and systems for determining and outputting in real-time the heart rate, pulse and oxygenation of a patient.
2. Description of Related Art
Pulse and heart rate are both well-known measures to obtain vital statistics of a patient. The pulse can be obtained and pulse rate measured at any location on the body where an artery's pulsation can be transmitted to the surface, typically through pressure. For instance, the pulse may be detected, and pulse rate measured, at locations on the body where an artery can be pressed against bone, including, at the neck (carotid pulse), wrist (radial pulse), finger, hand, foot, etc. At any of these locations, the pulse may be measured by a medical professional pressing their fingers down on the location to feel the pulse and count the number of pulses or beats at such location.
The pulse and pulse rate may also be detected and measured through indirect methods. One such indirect approach is through the measure of light absorption of varying wavelengths in a patient's blood to determine the oxygenation of the patient's hemoglobin. This technique is known as pulse oximetry. Conventional pulse oximetry uses a sensor placed on a thin part of the patient's body, whereby light at red (660 nm) and infrared (940 nm) wavelengths is passed sequentially through the patient to a photodetector. Oxygenation of the blood is measured based upon the ratio of changing absorbance of such red and infrared light through spectral anaylsis. Once measured, both the obtained oxygen level and pulse rate are then displayed on a monitor to the medical professional(s).
Pulse oximetry data is important whenever a patient's oxygenation may be unstable, such as, for instance in intensive care, surgery, emergency and even at birth. However, current pulse oximeters used to detect and measure pulse and pulse rate have a lag time. This lag time extends from the time the pulse oximeter is applied to the patient, to the time a pulse is detected, to the time needed to calculate oxygen level and pulse rate, to the final output of such measures to the medical professional. When time is of the essence, especially at birth when mere seconds are critical to the well-being of the newborn, any such lag time is undesirable. Known pulse oximeters are also influenced by several external conditions including, altitude, temperature, lighting, involuntary movements and nail polish, that affect the accuracy and validity of the readings output by such conventional pulse oximeters. Internal conditions of the patient may also affect the output readings of known pulse oximeters.
Heart rate is another vital statistic, and is often used interchangeably with pulse rate. Heart rate is the number of heartbeats per unit of time, often expressed as beats per minute (i.e., bpm). The heart rate measure may be the same as, or different from, the pulse rate measure.
One approach of obtaining heart rate is by finding a pulse on the patient, counting the pulses or beats, and then calculating the heart rate. For instance, the radial pulse resides at the wrist whereby the radial pulse is felt and measured to obtain a radial pulse rate. Alternatively, the pulse may be detected auditorily and listened-to-beats counted. For an essentially accurate reading, heart rate is obtained by measuring the pulse at a point of maximal impulse (PMI). This type of pulse is referred to as an apical pulse and is generally taken with a stethoscope located on the left side of the chest, about 2 inches to the left from the end of the sternum. As such, an apical heart rate is obtained by taking the pulse over the apex of the heart. An apical heart rate is generally a more accurate and reliable measure of heart rate, as compared to obtaining a heart rate at a location other than at the apex of the heart (e.g., as compared to obtaining a radial pulse/heart rate at the radial bone of the wrist).
In most cases, the apical heart rate will equal heart rates obtained at other locations across the body (i.e., at non-apical pulse locations), and vice versa. However, when the apical heart rate is higher than the non-apical heart rate (e.g. the radial pulse/heart rate), a pulse deficit is observed. This pulse deficit indicates that there is a problem with the blood getting to the arterial point at which such non-apical pulse was taken. Medical attention is often required in such situations. While a pulse deficit may be observed with the apical pulse being lower than the radial pulse, such an occurrence is typically due to human and/or mechanical error.
The heart rate may also be measured using a heart-monitoring device that has a probe positioned over the patient's heart for outputting a heart rate measure to a medical professional. This enables the medical professional to both diagnose and monitor various medical conditions.
One example of a heart-monitoring device is taught in U.S. Pat. No. 6,210,344, issued to Perin, et al., for a method and apparatus for passive heart rate detection. Briefly, this reference teaches a method and apparatus for measuring the heart rate of a patient, which includes a hollow bell mounted on a diaphragm. A transducer element is positioned to receive sound transmitted through the diaphragm, convert the sounds into electrical impulses, and transmit the electrical impulses to a microprocessor. The electrical impulses have real-time wave patterns corresponding to the real-time wave patterns of the original sounds. The microprocessor performs mathematical operations on wave pattern data conveyed by the electrical impulses to determine a numerical value corresponding to the frequency of the wave patterns. This numerical value is sent to a digital output and displayed thereon.
U.S. Pat. No. 5,218,969, issued to Bredesen, et al., discloses an intelligent stethoscope. This intelligent stethoscope is used for performing auscultation and for automatically diagnosing abnormalities based on body sounds wherein the body sounds are received, digitized and stored in memory. The body sounds are recorded from a plurality of locations on the body, and all of the sounds are categorized according to specific characteristics to form a matrix of information. The generated matrix is then compared against a plurality of stored matrices using a technique similar to analysis. Each of the stored matrices contain information indicative of known abnormalities such as specific heart murmurs, lung abnormalities, etc. When a matrix match is found, the diagnosis is displayed on an LCD display formed in the body of the stethoscope. The LCD display is also capable of displaying a visual representation of the recorded body sounds.
Still another prior art reference, U.S. Pat. No. 4,436,096, issued to Dyck, et al., discloses a portable digital heart rate meter/stethoscope. This prior art reference discloses that electrical signals corresponding to heart sounds detected by a pulse/sound transducer are filtered in a narrow band pass filter, whose pass band is centered on a characteristic heart sound frequency of 33 Hz. The filter improves signal-to-noise ratio and enables the transducer to be used over a patient's clothing. The unfiltered signal is amplified and fed to binaural leads to provide the function of an electronic stethoscope. In addition, the filtered signal is converted into pulses in response to which a count corresponding to the detected heart rate is established in a counter and displayed as a digital heart rate indication.
While known mechanical heart rate and pulse monitoring devices are each individually useful after baseline information has been attained, such as those described above, they are not useful when time is of the essence and only a hands-on auscultation is reliable. Furthermore, such known devices do not allow the entire medical team to have a comprehensive awareness of the medical condition of the patient in an immediate and reliable manner. Accordingly, a need continues to exist in the art for improved heart rate and pulse monitoring devices that can be relied on when time is of the essence, and subsequent to such time.


A brake shoe adapted to engage the tread of a railroad car wheel via which such railroad car is guidably supported on a railed track. The brake shoe comprises a backing plate which has a predetermined configuration and a means disposed on each end of the backing plate for securing such backing plate to a brake head. The brake shoe further includes a brake lining that is affixed to the backing plate and has a braking surface engageable with the wheel tread of a railroad car wheel.

The present invention relates, in general, to brake shoes and brake heads for railway vehicles; i.e., railway cars, transit cars and locomotives and, more particularly, the present invention relates to a keyless attachment of a brake shoe to the brake head.
Railway vehicles traditionally use a braking system wherein a brake shoe is forced against the wheel surface of the vehicle to provide a retarding force. The brake shoe is mounted to a brake head that is used to locate the brake shoe and provide the braking force to the brake shoe.
These railway brake shoes are typically mounted on such brake rigging of railway vehicles by means of a brake shoe key, which passes through a longitudinal slot in the brake shoe holder or brake head of the brake rigging and concurrently through mounting holes of the brake shoe backing plate. Such holes are normally located in a central xe2x80x9ckeybridgexe2x80x9d area of the brake shoe backing plate. The keybridge area of the backing plate is generally formed in such a way that it is adapted to protrude into or intersect with a longitudinal slot in the brake head at or near the center of the brake head""s length. Thus, the shoe is held in place in the brake head by this key that passes through openings in the brake head and the brake shoe as is seen in FIG. 1.
The brake shoe keys that are used to retain the brake shoes have a history of problems including not only working loose due to vibration but also breaking while in service. If either of these problems occur then the brake shoe will not be held in place properly and will not contact the wheel properly and more likely the brake shoe will fall off. If the brake shoe falls off then the brake head will contact the wheel during a brake application which results in both an unsafe brake application and possible detrimental damage to both the wheel and brake head. Further, the use of these brake shoe keys means that these keys must be kept in inventory and thus be available to maintenance personnel for attaching a new brake shoe.
The present invention provides a brake shoe adapted to engage the tread of a railroad car wheel via which such railroad car is guidably supported on a railed track. The brake shoe comprises a backing plate which has a predetermined configuration and a means disposed adjacent each end of the backing plate for securing such backing plate to a brake head. The brake shoe further includes a brake lining that is affixed to the backing plate and has a braking surface engageable with the wheel tread of a railroad car wheel.
Accordingly, it is a primary object of this invention to provide a new and improved brake shoe for railway vehicles having improved means for securing the brake shoe to the brake head.
Another object of this invention is to provide a brake shoe for railway vehicles wherein the means for securing the brake shoe to the brake head can be formed integrally as a portion of the backing plate of such brake shoe.
Yet another object of the present invention is to provide a brake shoe for railway vehicles wherein the means for securing the brake shoe to the brake head can be welded to the backing plate.
It is still another object of the present invention to provide a specially configured spring clip to secure the brake shoe to the brake head.
Another object of this invention is to provide a brake shoe for railway vehicles wherein the means for securing the brake shoe to the brake head can minimize damage to brake heads and wheels.
Still another object of the present invention is to provide a brake shoe for railway vehicles wherein the specially configured spring clip can reduce inventory.
Yet another object of this invention is to provide a brake shoe for railway vehicles wherein the means for securing the brake shoe to the brake head which will be cost effective.
Another object of this invention is to provide a brake shoe for railway vehicles wherein the means for securing the brake shoe to the brake head can be retrofitted to existing brake heads.
Still yet another object of this invention is to provide a brake shoe for railway vehicles wherein the means for securing the brake shoe to the brake head is easier to install.
These and other objects and advantages of this invention will become apparent after a full reading of the following detailed description, particularly, when read in conjunction with the attached drawings as described below and the appended claims.

Westinghouse Air Brake Technologies Corporation


Water produced in a fuel cell is managed and/or regulated by an assembly comprising at least one hydrophobic element and a hydrophilic element. The hydrophilic element is in contact with at least one first area of an outer surface of the cathode. The hydrophobic element covers the whole of a face of the hydrophilic element opposite the outer surface of the cathode and comprises at least one through opening releasing an area of said face of the hydrophilic element.

The invention relates to a fuel cell and more particularly a fuel microcell comprising:                a successive stacking of an anode, an electrolytic membrane and a cathode,        and an assembly arranged on at least a part of an outer surface of said cathode and comprising at least one hydrophilic element in contact with at least one first area of the outer surface of the cathode and a hydrophobic element covering the whole of a face of the hydrophilic element opposite the outer surface of the cathode.

Fuel cell comprising an assembly capable of managing the water generated by said cell


Message are broadcast in a vehicular environment using a network of nodes, wherein each node includes a transceiver and a processor arranged in a vehicle, and a bandwidth of the network is partitioned into a control channel (CCH) and multiple service channel (SCH). Time is partitioned into alternating control channel intervals (CCHI) and service channel intervals (SCHI). A source node detects an event and broadcasts a message related to the event. The message specifies current channels and next channels used by the source node to broadcast the message. The message is received in a set of relay nodes. Then, each relay node that receives the message rebroadcasts the message during the SCHI on the CCH or any other channels not specified in the message.

Governments and manufacturers are cooperating to improve traffic and vehicle safety using vehicular ad-hoc networks (VANETs), e.g., as specified by the IEEE 802.11p and IEEE P1609 standards. Other standards, such as continuous air-interface, long and medium range (CALM) can also be used. Vehicles in VANETS broadcast traffic and vehicle information, such as a location, velocity, acceleration, and braking status in periodic heartbeat messages, typically every 100 milliseconds.
The Federal Communications Commission (FCC) has allocated a 75 MHz bandwidth at 5.9 GHz for intelligent traffic system (ITS) applications such as VANETS. The bandwidth is allocated exclusively for vehicle-to-vehicle (V2V) communications and vehicle-to-infrastructure (V2I) communications. Dedicated short range (≈0.3 to 1 km) communications (DSRC) has been adopted as a technique for ITS services on this bandwidth.
The bandwidth is partitioned into multiple channels, e.g., seven 10 MHz channels including a control channel (CCH) and six service channels (SCH). The CCH CH178 is only used for public safety and control purposes. No private services are allowed on the CCH. The six SCH service channels are CH172, CH174, CH176, CH180, CH182, and CH184. Channels CH174, CH176, CH180, and CH182 are used for public safety and private services. Channels CH172 and CH184 are allocated as dedicated public safety channels, V2V public safety channel and intersection public safety channel, respectively. It should be noted that other channel partitioning schemes can be used.
Transmit powers limits are defined for the channels. CH178 has two transmission power limits, 33 dBm for non-emergency vehicles, and 44.8 dBm for emergency vehicles. For the middle range service channel CH174 and CH176, the transmission power limit is 33 dBm. For the short range service channel CH180 and CH182, the transmission power limit is 23 dBm. For dedicated public safety channels CH172 and CH184, the transmission power limits are 33 dBm and 40 dBm, respectively.
DSRC is standardized in a Wireless Access in Vehicular Environments (WAVE) protocol according to the IEEE 802.11p and IEEE P1609 standards. For channel coordination and channel synchronization, WAVE partitions time into 100 millisecond Sync Intervals. Each Sync Interval is further partitioned into a 50 milliseconds control channel interval (CCHI), and a 50 milliseconds service channel interval (SCHI). A 4 millisecond Guard Interval (GI) at the beginning of each channel interval accommodates variations in timing.
During the CCHI, high priority messages are broadcasted on the CCH while all transceivers monitor the CCH. The messages can be broadcasted on any channel during the SCHI. In a multi-channel wireless communication network, it is more difficult to reliably broadcast high priority messages than in a single channel network where all transceivers use a common channel all of the time.
WAVE imposes a 54 millisecond latency due to the existence of SCHI and Guard Interval. If an event is detected near the beginning of the SCHI, it takes at least 54 milliseconds to receive the corresponding message during the next CCHI. Even if the message is broadcasted immediately on current operation channel, the latency can still be at least 54 milliseconds for transceivers using different channels. A vehicle moving at 100 km/h travels 1.5 meters in 54 milliseconds, which is long enough to cause an accident. Therefore, a latency of 54 milliseconds is unacceptable.
The FCC has established three priority levels for ITS messages: safety of life, public safety, and non-priority. The lower priority messages can tolerate transmission latency, while high priority messages cannot. Based on the three priority levels, the SAE J2735 standard defines formats for a la carte message, a basic safety message, a common safety request message, an emergency vehicle alert message, and a generic transfer message.
The basic safety message contains safety-related information that is periodically broadcast. The common safety request message allows for specific vehicle safety-related information requests to be made that are required by vehicle safety applications. The emergency vehicle alert message is used for broadcasting warnings that an emergency vehicle is operating in the vicinity. The probe vehicle data message contains status information about the vehicle for different periods of time that is broadcasted to roadside equipment. The a la carte and generic transfer messages allow for flexible structural or bulk message exchange.
Of particular concern to the invention are high priority messages, such as crash-pending notification, hard brake, and control loss, which can only have a latency of up to 10 milliseconds. Other warning messages can have a latency up to 20 milliseconds, e.g., emergency vehicle approaching The messages, such as probe and general traffic information, can have a latency of more than 20 milliseconds.
The 54 milliseconds or greater latencies in the WAVE standard do not satisfy latency requirements of the SAE. Therefore, the latency in WAVE networks needs to be reduced.

Broadcasting messages in multi-channel vehicular networks

Mitsubishi Electric Research Laboratories, Inc.


An alkali metal, solid cathode, nonaqueous electrochemical cell capable of delivering high current pulses, rapidly recovering its open circuit voltage and having high current capacity, is described. The stated benefits are realized by the addition of at least one organic sulfate additive to an electrolyte comprising an alkali metal salt dissolved in a mixture of a low viscosity solvent and a high permittivity solvent. A preferred solvent mixture includes propylene carbonate, dimethoxyethane and a sulfate additive having at least one unsaturated hydrocarbon containing a C(sp.sup.2 or sp.sup.3 )--C(sp.sup.3) bond unit having the C(sp.sup.3) carbon directly connected to the --OSO.sub.3 -- functional group, or a silyl sulfate or a tin sulfate.

1. Field of the Invention
The present invention generally relates to an alkali metal electrochemical cell, and more particularly, to an alkali metal cell suitable for current pulse discharge applications with reduced or no appreciable voltage delay.
2. Prior Art
The voltage response of a cell which does not exhibit voltage delay during the application of a short duration pulse or pulse train has distinct features. First, the cell potential decreases throughout the application of the pulse until it reaches a minimum at the end of the pulse, and second, the minimum potential of the first pulse in a series of pulses is higher than the minimum potential of the last pulse. FIG. 1 is a graph showing an illustrative discharge curve 10 as a typical or "ideal" response of a cell during the application of a series of pulses as a pulse train that does not exhibit voltage delay.
On the other hand, the voltage response of a cell which exhibits voltage delay during the application of a short duration pulse or during a pulse train can take one or both of two forms. One form is that the leading edge potential of the first pulse is lower than the end edge potential of the first pulse. In other words, the voltage of the cell at the instant the first pulse is applied is lower than the voltage of the cell immediately before the first pulse is removed. The second form of voltage delay is that the minimum potential of the first pulse is lower than the minimum potential of the last pulse when a series of pulses have been applied. FIG. 2 is a graph showing an illustrative discharge curve 12 as the voltage response of a cell that exhibits both forms of voltage delay.
The initial drop in cell potential during the application of a short duration pulse reflects the resistance of the cell, i.e., the resistance due to the cathode, the cathode-electrolyte interphase, the anode, and the anode-electrolyte interphase. In the absence of voltage delay, the resistance due to passivated films on the anode and/or cathode is negligible. However, the formation of a surface film is unavoidable for alkali metal, and in particular, lithium metal anodes, and for lithium intercalated carbon anodes, due to their relatively low potential and high reactivity towards organic electrolytes. Thus, the ideal anode surface film should be electrically insulating and ionically conducting. While most alkali metal, and in particular, lithium electrochemical systems meet the first requirement, the second requirement is difficult to achieve. In the event of voltage delay, the resistance of these films is not negligible, and as a result, impedance builds up inside the cell due to this surface layer formation which often results in reduced discharge voltage and reduced cell capacity. In other words, the drop in potential between the background voltage and the lowest voltage under pulse discharge conditions, excluding voltage delay, is an indication of the conductivity of the cell, i.e., the conductivity of the cathode, anode, electrolyte, and surface films, while the gradual decrease in cell potential during the application of the pulse train is due to the polarization of the electrodes and electrolyte.
Thus, the existence of voltage delay is an undesirable characteristic of alkali metal/mixed metal oxide cells subjected to current pulse discharge conditions in terms of its influence on devices such as medical devices including implantable pacemakers and cardiac defibrillators. Voltage delay is undesirable because it limits the effectiveness and even the proper functioning of both the cell and the associated electrically powered device under current pulse discharge conditions.
The present invention is directed to the provision of sulfate additives in the electrolyte of an alkali metal electrochemical cell to beneficially modify the anode surface film. The sulfate additives preferably include at least one unsaturated hydrocarbon containing a C(sp.sup.2 or sp.sup.3)--C(sp.sup.3) bond unit having the C(sp.sup.3) carbon directly connected to the --OSO.sub.3 -- functional group, or are a silyl sulfate or a tin sulfate, and are provided as a co-solvent with commonly used organic aprotic solvents. The organic sulfate additives are in a condensed phase which makes them easy to handle in electrolyte preparation. When used as a co-solvent in an activating electrolyte, the sulfate additives interact with the alkali metal anode to form an conically conductive surface protective layer thereon. The conductive surface layer improves the discharge performance of the alkali metal electrochemical cell and minimizes or even eliminates voltage delay in the high current pulse discharge of such cells.

Method for reducing voltage delay in an alkali metal electrochemical cell activated with a nonaqueous electrolyte having a sulfate additive


A process for preparing an alkoxyalkanoic acid by reacting the corresponding alkoxyalkanol with a resin-supported stable free radical nitroxide in the presence of a chlorine-containing oxidant and a solvent at a temperature in the range of from about 0.degree. C. to about 35.degree. C. and thereafter separating out the alkoxyalkanoic acid.

Alkoxyalkanoic acids are useful as anionic surfactants or emulsifying agents. These acids, being composed of only the elements C, H and O, do not pose the environmental problems that other detergents containing heteroatoms such as N, S, and P pose. The alkoxyalkanoic acids can be prepared in a two-step process of first reacting an alkanol with an alkoxylate and a suitable alkoxylation catalyst and thereafter converting the resultant alkoxyalkanol to the alkoxyalkanoic acid.
It is also known to convert alkoxyalkanols such as methyl carbitol to the corresponding carboxylic acids by oxidizing them with nitric acid. However, relatively large amounts of nitric acid are required and not all of the nitric acid can be separated by distillation. In addition, cleavage of the ether linkages occurs to a large degree during this process.
Japanese Patent No. 50-96516, issued Jul. 31, 1975, discloses a process for the preparation of carboxylic acid salts by the liquid phase dehydrogenation of alcohols with caustic alkali in the presence of precious metal catalysts, including palladium. This process uses a relatively high temperature, 100.degree. C.-270.degree. C. These high temperatures can degrade the ether linkages especially in the highly ethoxylated alcohols.
It is known to use nitroxyl radicals/oxoammonium salts in the oxidation of primary alcohols to produce aldehydes and acids and secondary alcohols to ketones. Journal of Organic Chemistry, Vol. 52(12), pp. 2559-2562; Pure and Applied Chemistry, Vol. 62(2), 1990, pp. 217-222; Journal of Organic Chemistry, Vol. 55, 1990, pp. 462-466. The primary products produced in these processes are aldehydes and the stoichiometrically consumed oxidant is hypochlorite.
It is generally more difficult to oxidize alkoxyalkanols than alkanols as it is difficult to oxidize alkoxyalkanols without splitting the molecular chain at the ether linkage and thereby produce a large proportion of undesired by-product. It would therefore be advantageous to produce alkoxyalkanoic acids in high yields and with high selectivities without producing large amounts of other products such as aldehydes, esters, and alkanoic acids. It would also be advantageous to have a supported nitroxide to make separation of the product easier and to enable the supported nitroxide to be isolated and reused.
It has been found that alkoxyalkanoic acids having high selectivities can be produced without forming highly corrosive, difficult to separate, side-products by using catalytic amounts of a resin-supported stable free radical nitroxide, a chlorine-containing oxidant and a solvent.


A towed vehicle deployment and retrieval system for attachment to an aircraft. The system includes a pylon support that is designed to mount to an aircraft and project outward therefrom. A stores pylon is mounted to the pylon support. The stores pylon has at least one swaybrace reciprocally attached to it for removably engaging with a towed vehicle. The system also includes a winch that is configured for mounting within the aircraft. The winch controls the feeding and retrieval of a winch cable that is attached to the towed vehicle. A tow cable is removably attached to the aircraft and is engaged with the winch cable using a tow pole such that the tow cable fully supports the towed vehicle when the towed vehicle is in the towing position. A method is also disclosed for attaching a winch cable and towed vehicle to a tow cable.

Mines and similar water submersed explosive devices can cause significant damage to naval vessels, not to mention harm and/or death to personnel on such vessels. One of the methods currently employed to detect and destroy submersed mines is by dragging a towed vehicle over the area of concern. The towed vehicle is submersed behind an aircraft and includes electrical circuitry for detecting and destroying submersed mines. Raytheon Corporation makes an AQ-S20 towed vehicle which is submersible and controlled via fiber optics embedded into a tow cable. Typically, the towed vehicle is hauled behind a helicopter during an Airborne Mine Countermeasures (AMCM) mission. The importance of the AMCM mission was highlighted during the Persian Gulf War when three US Navy warships struck World War I era mines, causing significant damage to the ships and nearly sinking one.
Currently, the AMCM towing mission is performed using a Sikorsky Aircraft Corporation S-65 series aircraft, particularly, the US Navy MH-53E and the Japan Naval Defense Force S-80M. These aircraft are very large and include an interior cabin with a retractable ramp. An airborne towed vehicle is retained within the cabin until deployment. The towed vehicle is stored in a cradle which can be moved fore and aft in the cabin. When it is desired to deploy the towed vehicle, the cradle is moved to the rear ramp. An A-frame assembly mounted to the aircraft above the ramp is used to lift the towed vehicle from the cradle. The cradle is then moved away and the ramp is lowered to a vertical position, clearing the area beneath the suspended towed vehicle. The towed vehicle is then lowered into the water using a cabin mounted winch. The cable that supports the towed vehicle includes a tow ball which is designed to engage with a hook formed on a tow boom mounted to the helicopter. This allows the tow boom and helicopter to support the towing loads and unload the winch. The operation is reversed to recover and stow the vehicle.
Due to the large size of the S-65 aircraft used in the AMCM mission, these aircraft are only compatible with large naval vessels, such as helicopter/aircraft carriers. To meet the diverse needs of the Navy, the United States military currently maintains forces that are dedicated to performing the AMCM mission. These forces are deployed to areas of concern on an as-needed basis. Accordingly. deployed naval forces must wait until the AMCM forces to arrive, detect and clear the area of mines.
A need therefore exists for a more versatile airborne towed vehicle deployment and retrieval system that can be used with smaller aircraft which are more readily available to the naval forces.

System for deployment and retrieval of airborne towed vehicles


The three dimensional configuration of an article is generated from a plurality of sheets of polymer material having a base resin constituent, a reactive diluent constituent and a reaction modifying constituent which effects a latent change in chemical reactivity of the polymer material in an area of each sheet imaged with actinic radiation in the configuration of an incremental heighth of the article, successive sheets are exposed to actinic radiation corresponding to the configuration of successive incremental planar heighths of the article and are stacked in a matrix. The imaged areas of all sheets are thereafter simultaneously cured with heat or aging, the configuration of the article is separated from the remainder of the matrix by altering the dimensional stability of the uncured polymer material. The sheets may be initially positioned on a carrier web for transport through an apparatus for constructing the shape of an article. The apparatus includes an imaging station wherein successive sheets are exposed to actinic radiation and a stacking station wherein exposed sheets are stripped from the carrier web and placed in a stack to form the matrix.

1. Field of the Invention
This invention relates generally to the formation of a solid article from a mathematical or graphical representation and more particularly to a system for generating the shape of an article by actinic irradiation of successive sheets which comprise a matrix which supports the article during formation.
2. Related History
Since the implementation of computer technology for physical design purposes, there has been an appreciation of the need for expanding use of computers to control the fabrication of prototypes of articles which have been designed. While the principle of irradiating an article to effect changes in molecular structure and physical properties has been long recognized, such phenomenon had not been employed for the purpose of generating three-dimensional articles until recent years. In this regard, attempts have been made to utilize a fluid medium containing a curable material which was irradiated by a plurality of beams. The energy level at the intersection of the beams was sufficient to cure the material within the fluid medium. Such apparatus did not gain widespread acceptance due to many inherent disadvantages including cost, resolution difficulties and insufficient energy levels as a result of absorption as the depth of beam penetration into the fluid medium increased.
In U.S. Pat. No. 4,575,330, an apparatus for constructing an article by ultra violet polymerization of the upper surface of a photopolymeric fluid medium was disclosed. Successive layers of the article were generated by successively lowering built up polymerized layers into the fluid medium so that the upper surface of the fluid medium contained unpolymerized material suitable for polymerization and generation of the next layer.
While the apparatus did not require multiple beams, it suffered from several disadvantages, including restricted photopolymeric material requirements. It was limited to use with ultra violet beams and required photopolymers responsive to the ultra violet wavelengths. In addition, difficulties were encountered in maintaining the upper surface of the fluid medium at a planar reference level due to fluid turbulence, reduction in fluid level as a result of the polymerization of prior layers and uneven shrinkage of the polymerized material. Also, the apparatus lacked precise control over the depth of polymerization into the fluid medium which resulted in loss of axial resolution.
Further, because a fluid medium was used, the article being constructed could not be supported except by the underlying built up article layers and a support platform, movable within the medium, was required. As such, articles having surfaces contoured with undercuts and the like could not be generated without providing a complicated mechanism capable of moving the platform along multiple axes.
In addition, in order to provide sufficient energy levels for curing, the maximum scan speed of the ultra violet beam was relatively slow, resulting in a correspondingly slow overall throughput.
In copending application Ser. No. 07/312,613 filed Feb. 17, 1989, an article shaping system was described wherein sheets of thermoplastic polymer mixture were stacked on a platen and the uppermost sheet was irradiated with an electron beam deflected to trace the configuration of a incremental planar heighth of the article. The beam effected cross-linking of the polymer along the trace to convert, for example, a thermoplastic polymer to a thermoset. As successive sheets were placed on top of one another and irradiated, the stack formed a matrix which supported the built up configuration of the article. The matrix was thereafter removed by heat and/or solvents. Such system provided enhanced image resolution, reduced mechanical complexity and greater material compatibility than prior methods. Throughput was increased because the electron beam provided an efficient irradiation source and the sheets could be stacked and referenced rapidly.
Unfortunately, the production of large and detailed components could still take many hours. Further, the efficient production of a suitable electron beam required expensive evacuation hardware systems and high voltage biasing equipment. Additionally, image penetration into underlying sheets presented a problem which could be alleviated by precise control of the beam energy level or the use of sheets of polymer mixture with depthwise varying degrees of reactivity.
A system for computer aided generation of three dimensional articles utilizes sheets of thermoplastic polymer mixture adhered in discrete locations on a continuous carrier web. Successive sheets are individually imaged with actinic radiation in the configuration of successive incremental planar heighths of the article. The actinic radiation affects the tendency of the imaged areas of each sheet to undergo subsequent curing which results in a modification of a physical property such as a change in solubility and/or rheology. The irradiated sheets are stripped from the carrier web and stacked in a matrix. The imaged areas of all sheets are simultaneously cured with heat and/or aging.
Depending upon the particular polymer mixtures employed, the actinic radiation serves, e.g. to facilitate subsequent curing which changes a thermoplastic into a thermoset or alters the solubility of a constituent polymer in a particular solvent by modifying functional side groups of linearly branched polymer chain structures and/or the molecular weight of the polymer.
The polymer mixture chosen for the sheets comprises a base resin, a reactive diluent and a reaction modifying compound coupled with an activating compound responsive to the radiation employed for imaging. Although the components of the polymer mixture are functionally distinct, they are not required to be physically distinct.
For catalytically induced reactions, the base resins are typically higher molecular weight polymers which act as film formers and contain functional groups typical of such reactions, e.g. epoxy, hydroxy, carboxy. The reactive diluents contain mono- or multi-functionalities typically co-reactive with those of the base resin, and are generally lower molecular weight monomers, oligomers, or prepolymers which, when reacted with the base resin, substantially alter the physical and/or chemical properties of the polymer mixture. Reaction modifying compounds include cationic photo catalysts such as diaryliodonium, triarylsulfonium, and mixed-ligand arene cyclopentadienyl metal salts, and may also include photosensitizers compatible with such catalysts.
In lieu of catalytic activation mechanisms, an article shape can be realized through a photo-activated deprotection of reactive functionalities which results in subsequent polymer structure modification. The base resins employed are film forming polymers which may contain blocked and/or mutually non-reactive free functionalities such as suitable combinations of hydroxyl, aldehyde, amine, and isocyanate moieties. The reactive diluents contain mono- or multi-functionalities which may be co-reactive with those of the base resin. The diluents are generally lower molecular weight monomers, oligomers and prepolymers with blocked and/or mutually non-reactive free functionalities.
The reaction modifying protecting groups are previously reacted with specific functionalities in either the base resin or the reactive diluent or both, and cleave under actinic radiation to free these functionalities. Cleavage may be obtained by a direct photolytic activation, or indirectly such as by a photo-catalyzed de-blocking. Additional photo-sensitizing compounds may be used to alter the spectral-response of these reactions.
The sheets of polymer mixture are adhered onto the carrier web in discrete areas and comprise a substantially uniform thickness stratum of polymer mixture. When the stratum is not typically self-adherent, a substratum or tack layer may be formed of a polymer mixture similar to the stratum with lower molecular weight constituents or additional tackifying resins to temporarily adhere the sheet to the web and to thereafter adhere imaged sheets to one another when stacked.
An apparatus for imaging and consolidating the sheets includes a mechanism for transporting successive sheets carried on the web to an imaging station and for transporting the imaged sheets to a stacking station. The imaging station includes a cathode ray tube or a sequence of photomasks, and an optical projection system. At the stacking station the sheets are stripped from the web and placed on a stack which forms a matrix.
The image irradiated on each sheet comprises the configuration of the article to be formed at an incremental heighth which conforms to the thickness and Dosition of such sheet. The actinic radiation initiates a modification of the reactive properties of the imaged areas on a sheet. Under the subsequent influence of heat and/or age curing, a substantially simultaneous differentiation of the image and non-image areas of the sheets occurs. After curing, the remainder of the stack is removed by heat, pressure or chemical dissolution or dispersion.
From the foregoing compendium, it will be appreciated that it is an aspect of the present invention to provide an article shaping system of the general character described which is not subject to the disadvantages of the related history aforementioned.
A feature of the present invention is to provide an article shaping system of the general character described capable of constructing three-dimensional prototypes of computer designed articles with precise dimensional accuracy.
A consideration of the present invention is to provide an article shaping system of the general character described which does not require complex mechanical structures or multiple irradiation beams to form intricate shapes.
It is another consideration of the present invention to provide an article shaping system of the general character described wherein the article may be formed from a wide variety of materials having different physical properties.
Another feature of the present invention is to provide an article shaping system of the general character described capable of generating a three-dimensional article with relatively high speed.
To provide an article shaping system of the general character described which is relatively low in cost is a further aspect of the present invention.
Providing a computer controlled article shaping system of the general character described with enhanced vertical definition is another aspect of the present invention.
A further consideration of the present invention is to provide an article shaping system of the general character described which utilizes low intensity actinic rays for configuring an article shape in successive sheets of a built up support matrix.
Another feature of the present invention is to provide an article shaping system of the general character described which utilizes actinic imaging for initiating latent chemical modification in the form of the shape of an incremental planar heighth of an article on successive sheets of a support matrix.
A still further feature of the present invention is to provide a method of the general character described for shaping an article whereby the configuration of the article is generated by latent imaging of sheets which are stacked to provide a support matrix for the article as its shape is being generated.
Yet another aspect of the present invention is to provide an article shaping system of the general character described which is relatively simple to use.
Other aspects, features and considerations in part will be obvious and in part will be pointed out hereinafter.
With these aims in view, the invention finds embodiment in certain combinations of elements, arrangements of parts and series of steps by which the said aspects, features and considerations and certain other aspects, features and considerations are attained, all with reference to the accompanying drawings and the scope of which is more Darticularly pointed out and indicated in the appended claims.

Actinic activation article shaping system


An infrared and ultraviolet radiation absorbing glass suitable for use in building and vehicle windows, which comprises, on a weight basis, 68-74% of SiO.sub.2, 0.1-3.0% of Al.sub.2 O.sub.3, 8-11% of CaO, 2.0-4.5% of MgO, 11.5-16.0% of Na.sub.2 O, 0.5-3.0% of K.sub.2 O, 0.1-0.4% of SO.sub.3, 0.10-0.55% of total iron expressed as Fe.sub.2 O.sub.3, 0.2-0.6% of CeO.sub.2, 0.3-14 ppm of CoO and 5-20 ppm of Se. In the glass the ratio of ferrous iron to ferric iron is in the range from 0.17 to 0.55. The glass has a bronzy tint and is well balanced in visible light transmittance, infrared radiation absorption and ultraviolet radiation absorption, and a sheet of the glass can be easily tempered by a conventional method.

This invention relates to an infrared and ultraviolet radiation absorbing glass. The glass has a bronze color and sufficiently high transmittance for visible light and is particularly suitable for use in building and vehicle windows.
For windows of buildings, automobiles and other vehicles there is an increasing demand for sheet glass that is sufficiently transparent to visible light and absorptive of not only infrared rays but also ultraviolet rays.
It is known to render a soda-lime-silica glass absorptive of infrared and ultraviolet rays by incorporating iron in the glass. Ferrous iron expressed as FeO provides the glass with the absorption of infrared radiation, whereas ferric iron expressed as Fe.sub.2 O.sub.3 provides the glass with the absorption of ultraviolet radiation. In practice Fe.sub.2 O.sub.3 is used as the source of the entire iron, and an adequate portion of Fe.sub.2 O.sub.3 is reduced to FeO during the glassmaking process.
Also it is known to incorporate CeO.sub.2 and/or TiO.sub.2 in a soda-lime-silica glass for the absorption of ultraviolet radiation.
From an industrial point of view, it is desired that an infrared and ultraviolet absorbing glass in the form of sheet glass can be produced without significantly changing the conditions of conventional glass melting and refining operations. Also it is desired that an infrared and ultraviolet absorbing glass sheet can easily be toughened by a conventional tempering method. Besides, an infrared and ultraviolet absorbing glass sheet is desired to have a pleasing tint such as bronzy tint.
JP-A-52-102310 shows a neutral grayish- or bronze-colored infrared absorbing soda-lime-silica glass containing as essential components, on a weight basis, 65-75% of SiO.sub.2, 0-5% of Al.sub.2 O.sub.3, 5-15% of CaO, 0-10% of MgO, 10-18% of Na.sub.2 O, 0-5% of K.sub.2 O, 0.0005-0.02% of Cr.sub.2 O.sub.3, 0.0010-0.01% of CoO, 0.0001-0.03% of Se and 0.1-0.19% of Fe.sub.2 O.sub.3 with provisos that the total of CaO and MgO is from 0 to 16% and that the total of Na.sub.2 O and K.sub.2 O is from 10 to 20%. However, this glass is insufficient in absorption of infrared and ultraviolet radiation, and thus is not useful for vehicle windows.
JP-B-58-13504 shows a bronze-colored ultraviolet absorbing soda-lime-silica glass containing, on a weight basis, 0.2-0.5% of total iron expressed as Fe.sub.2 O.sub.3, 5-25 ppm of Se and 0-20 ppm of CoO. The optical characteristics of this glass at a thickness of 3 mm with using standard illuminant C are as follows.
Visible light transmittance Y is not less than 70%. Light transmittance in the wavelengths of ultraviolet rays is smaller than that in the wavelengths of visible light rays. The excitation purity Pe is from 2 to 6%. The dominant wavelength .lambda..sub.D is from 570 to 580 nm. However, this glass is still insufficient in ultraviolet radiation absorption.
JP-B-63-44695 shows a bronze-colored ultraviolet absorbing soda-lime-silica glass containing as essential components, on a weight basis, 65-75% of SiO.sub.2, 0.3-5% of Al.sub.2 O.sub.3, 5-15% of CaO, 1-10% of MgO, 10-18% of Na.sub.2 O, 0-5% of K.sub.2 O, 0.22-2% of Fe.sub.2 O.sub.3, 0-0.01% of CoO, 0.1-0.003% of NiO and 0.0005-0.015% of Se with provisos that the total of CaO and MgO is from 6 to 16%, that the total of Na.sub.2 O and K.sub.2 O is from 10 to 20% and that the weight ratio of Fe.sub.2 O.sub.3 to CoO is not less than 100. This glass exhibits a dominant wavelength of 580 to 590 nm by the 2.degree. visual field measurement with using standard illuminant A. However, this glass may change in color and may become weak in strength in heat treatment due to the addition of NiO.
U.S. Pat. No. 2,444,976 shows a ultraviolet absorbing glass having a golden tint, which contains, on a weight basis, 65.6% of SiO.sub.2, 0.4% of the total of Al.sub.2 O.sub.3 and Fe.sub.2 O.sub.3, 11.8% of CaO, 12.2% of Na.sub.2 O, 0.5% of As.sub.2 O.sub.3, 7.5% of TiO.sub.2 and 2.0% of CeO.sub.2. However, this glass is insufficient in infrared absorption.

Bronze-colored infrared and ultraviolet radiation absorbing glass


A method of applying a corrosion-resistant coating to a fastener that includes preheating an area of the fastener to be coated to elevate a temperature of the area and spraying the preheated area of the fastener with a molten or semi-molten metal. In one embodiment, a corrosion-resistant coating applicator includes a support structure, a rotatable slotted fastener conveyer supported by the support structure, a feeder configured to feed fasteners to the rotatable slotted fastener conveyer, a fastener aligner configured to make head portions of the fasteners aligned with each other, a heater configured to heat head portions of the fasteners as the fasteners are being conveyed by the slotted fastener conveyer, and a sprayer configured to apply a corrosion-resistant coating to the heated head portions of the fasteners being conveyed by the slotted fastener conveyer. The present disclosure also provides corrosion-resistant coated fasteners made using the coating methods and/or coating apparatus.

Steel nails often rust when exposed to the elements. To prevent this, corrosion-resistant finishes are typically utilized to protect the nails. One such method of incorporating corrosion protection is to manufacture nails from steel wire that is pre-plated with zinc to provide galvanic protection.
One problem with such method relates to the protection of the head or head portion of the nail. More specifically, the head portion of the nail is typically formed by deforming the steel wire. When the head portion of the nail is formed, the zinc plating on the steel wire is also deformed and often results in uneven distribution of zinc across the entire nail head portion. While the resulting zinc layer still provides certain amounts of galvanic corrosion protection, especially during the harsh conditions of exposure to moisture, the head portion of the nail thus often experiences at least some cosmetic corrosion over time at one or more of the locations on the head portion where the zinc is thinner or non-existent. This corrosion typically occurs in relatively milder dry conditions, where galvanic protection is only provided to areas covered with zinc. Improving the uniformity and continuity of the zinc layer on the nail head portion is highly desirable to improve corrosion resistance in all conditions.
Another problem relates to conventional methods used to entirely coat steel nails with heavy levels of zinc that require immersion of the nails in molten zinc at temperatures of 800 degrees to 1100 degrees Fahrenheit (which is sometimes referred to as "hot-dip galvanizing"). Such hot-dip galvanizing has various processing issues. First, hot-dip galvanizing is a batch process that can introduce variation from batch to batch. Second, adding a batch process in the middle of manufacturing a product can add to operational complexity, inefficiency, and expense. This process is also especially cumbersome when nails will be subsequently processed to be aligned and collated for use in automatic nail-driving tools. For instance, untreated nails are removed from the manufacturing line, hot-dip galvanized in a batch, and then the treated nails are reintroduced into the manufacturing line. The inventory of untreated nails and treated nails must be managed carefully not to cause delays in the manufacturing process. For example, if the inventory of treated nails is exhausted before the next batch of untreated nails finishes the hot-dip galvanizing batch process, the manufacturing process will be delayed. Third, handling the nails during hot-dip galvanizing typically heats the nails to a level that can cause the heated nails to become weakened and bend. Bent nails increase waste in the post-galvanizing processes and in many instances cannot be sold and need to be discarded. This increases waste and also increases cost. Fourth, the quality of the galvanized layer must be inspected for each batch that is processed. Variations from batch to batch can result in subsequent manufacturing difficulties and inconsistent quality of corrosion protection that is provided.
A known improved method versus this conventional hot-dip galvanizing process is to manufacture hot-dip galvanized wire and then cut and form the nails from that wire. There are advantages to this method. First, the wire galvanizing processes result in substantially smoother and more uniform zinc plating layers than the batch-galvanized nails. Nails made from such wire are substantially more uniform in dimension, and improvements in manufacturing efficiency and reductions in scrap are realized when nails are aligned and collated for use in automatic nail-driving tools. Second, galvanization of wire is typically a continuous process, which enables much larger quantities of steel to be galvanized in a batch than pre-formed nails. This greatly reduces the amount of inspection that must be performed to ensure that the zinc plating on the nails meets manufacturing and corrosion protection requirements.
However, a disadvantage to the manufacturing of nails from galvanized wire is that coverage of the zinc plating may not extend across the entirety of the formed nail head or head section. When the galvanized wire is cut and the head portion is stamped, the zinc plating on or around the head portion is disrupted. The zinc tends to be malleable and can flow in the same manner as the underlying steel to form the head; however, continuity is compromised and areas with little or no zinc can result on the top of the nail head surface. Practically, relatively enough corrosion resistance is maintained across and around the nail head surfaces due to the overall presence of zinc. Typical harsh environmental conditions that necessitate corrosion resistance in application include rain and condensation. Wet environmental factors enable the zinc to provide broad galvanic protection across the entire nail head surface when it is wet, almost regardless of the uniformity or continuity of the zinc layer. While drier conditions are not considered to be as corrosive to metals, drier environmental conditions do not permit zinc to have as much "throwing power", which enables exposed steel on the nail heads to oxidize locally and create superficial rust. Cosmetically, this is undesirable. The known solution to remedy this cosmetic issue is to apply an anti-corrosion paint on the nail head surface. This solution is not satisfactory because it provides a mixed barrier or mixed galvanic method of protection that is not the same as the rest of the nail.
Accordingly, there is a need to provide a new method and apparatus for applying a more consistent corrosion-resistant coating to fasteners (such as nails) that solve these problems. There is a need to provide new fasteners (such as nails) that solve these problems.

Method and apparatus for applying a corrosion-resistant coating to fasteners


When virtual printers are collectively registered with a plurality of print services through one operation, a virtual printer may be registered also with print services not utilized. In the present invention, by acquiring information regarding print services, provided by a plurality of print services, and information regarding virtual printers registered with the print services, it is determined, on a basis of the information regarding the virtual printers and a printer ID of the local printer, whether or not the local printer has been registered as a virtual printer with the print services. Information regarding the print service with which the local printer is determined not to have been registered is displayed, and when instructed by a user to register the local printer with the displayed print service as a virtual printer, the local printer is registered as the virtual printer with the instructed print service.

A technique is known in which, when a client transmits a print instruction to a server, the server which has received the print instruction converts content to be printed into print data and performs print processing by using the converted print data.
In PTL 1, a client apparatus, which has received from a user a request for printing application data created by an application within a server, transmits a generation request for generating print data from the application data to an application of the server. The server, upon receipt of the generation request and information regarding a client which has issued the generation request, generates print data in accordance with print control information according to the information regarding the client. In other words, the server described in PTL 1 provides a client with a service for generating print data.
Such a form of service in which a server provides a print service to a client is known. On the other hand, cloud computing, which has drawn attention in recent years, is also a form of service in which a server provides a service to a client. Cloud computing is mainly characterized in that requests from a plurality of clients are simultaneously processed in such a manner that data conversion or data processing is performed by using a lot of computing resources, through distributed computing. At present, there are a plurality of vendors which provide various services by implementing web services in this cloud computing environment.
On the other hand, a method is known in which printing is performed by directly transmitting print data from a mobile terminal, such as a smart phone, to a printer. In this method, document data needs to be converted into print data within the mobile terminal, thereby causing a shortage of memory in some cases, depending on the mobile terminal. The web server disclosed in PTL 2, upon receipt of a print request from an image forming apparatus, instructs a print service to generate print data. The image forming apparatus receives the print data from the print service and performs printing, and notifies the print service of a print status whenever the print status changes. A system for performing printing through the combination of such a mobile terminal, a printer, and a server is called cloud printing.
In order to make a plurality of print services that exist on a network available for use, registration of a virtual printer needs to be made for the printer services. A method for avoiding these laborious registration operations may involve collectively instructing the print services to register virtual printers. However, when virtual printers are collectively registered with all the print services, virtual printers, which are not actually used, may be registered.

Printer registration apparatus, display apparatus, and method for printer registration


A method for the computer-assisted configuration of an electrical power grid is provided. Grid forming generating unit nodes are provided in the power grid as first grid nodes and grid-boosting generating unit nodes are optionally provided as second grid nodes. The latter nodes are regenerative energy generation plants such as, for example, photovoltaic systems. In the method, closed-loop control methods and in particular proportional control of the generating unit nodes are set on the basis of a suitable dynamic model of the power grid such that an optimization problem is solved with the aim of optimum operation of the power grid in respect of one or more optimization criteria.

Electrical power grids comprise a plurality of grid nodes which are connected via power lines and in which electrical energy is produced or from which electrical energy is removed. In this case, the grid nodes are often controlled within the scope of proportional control in which the voltage and frequency of the individual nodes and their active power and reactive power which are fed in are set for said nodes. A distinction is made between grid-forming producer nodes and grid-supporting producer nodes. In a grid-forming producer node, which is also referred to as a voltage-controlled producer node, the amplitude and frequency of the voltage in this node are set within the scope of the proportional control. In contrast, in a grid-supporting producer node, which is also referred to as a current-controlled producer node, the active power and reactive power fed in are controlled within the scope of the proportional control.
In modern power grids, grid-supporting producer nodes are often regenerative energy production plants which contain power electronics, for example inverters, which are designed only for a particular maximum current. In the event of excessive fluctuations in the load in the power grid, the power grid may become unstable on account of current limitation of the grid-supporting producer nodes, which, under certain circumstances, may result in failure of the power grid. Consequently, the operation of the grid-supporting producer nodes is generally designed in such a manner that the maximum current is not reached in the event of sudden load changes. However, this results in the proportion of energy which is provided via regenerative energy production in the power grid being limited. This increases the power production costs since grid-forming producer nodes are increasingly being used for this purpose and are generally conventional generators, for example diesel generators or gas turbines.
Only a few approaches relating to how the proportion of regenerative energy production can be increased in a power grid are known from the prior art. Document [1] describes power grids in the form of so-called micro grids having a high proportion of regenerative energy production. However, large and overdimensioned electrical energy stores are used as grid-forming nodes in such grids. Simulation methods which are used to simulate different load changes in the grid are also known for the purpose of optimizing power grids. However, these methods are computationally intensive and can generally provide results only for a small number of possible load changes.

Method for the computer-assisted configuration of an electrical power grid


A multichannel recorder, such as for color video, reduces the width of recording heads that record low frequencies, and interchanges the order of one such head with a high frequency head. This both reduces crosstalk and keeps interchannel time displacement low.

The present invention relates to magnetic recording heads, and more particularly, to heads that are used in video tape recording such as for electronic news gathering apparatus.
In small portable recorders it is customary, due to the size and weight limitations, to record a video signal using two channels, one for the luminance signal and the other for the chrominance signal. The chrominance signal is usually directly recorded at base band, while the luminance signal is usually recorded using frequency modulation of a high frequency carrier. This approach allows a smaller headwheel to be used, while permitting the bandwidth and the signal-to-noise ratio to remain within acceptable limits. However, this approach does have problems. In particular, because of slight variations in tape tension across the width of the tape, one side of the tape may stretch slightly more than the other side during either recording or playback. This results in the chrominance signal begin slightly time displaced with respect to the luminance signal, and is therefore called "interchannel time displacement". To avoid this problem, it is desired to have the two recording tracks as close together on the tape as possible. Further, in order to minimize the size of the cassette, the length of the tape should be made as short as possible. This also requires that the recorded tracks should be made as close as possible. However, there is another problem in recording; during playback a head can pickup the recorded signal from an adjacent track, and during both record and playback inductive coupling between heads can occur. These effects are called "crosstalk". The crosstalk in the first case is proportional to the recorded wavelength, while the second crosstalk, since it is an inductive effect, increases at higher frequencies for a given fixed distance between adjacent heads. Therefore to minimize crosstalk, the heads should be located as far apart as possible. This clearly is in conflict with the requirement for minimizing the interchannel time displacement and tape length. It is possible to have the recording heads set at an azimuth angle to reduce the crosstalk, but this does not solve the problem since mistracking can occur which causes crosstalk despite the head angle.
It is therefore desirable to have a magnetic recording and playback head structure which minimizes both sources of crosstalk and interchannel time displacement.

Magnetic recording with reduced cross-talk and interchannel time displacement


A rail-rail comparator having an input stage with independent positive and negative differential voltage offset compensation tracks changes in Gm (transconductance) of the input stage. By tracking the changes in Gm (transconductance) of the input stage, hysteresis of the rail-rail comparator becomes insensitive to the input common mode voltage. A two-stage rail-rail comparator may be used for adding hysteresis to a second stage. The first stage of the two-stage rail-rail comparator operates at substantially unity gain. The second stage of the two-stage rail-rail comparator operates as a regular high gain amplifier with hysteresis. Additional circuitry tracks the Gm (transconductance) change of the first stage to make the second stage hysteresis insensitive to the input common mode voltage at the first stage. This also makes it easier to create a programmable hysteresis that is accurate over all input voltage values.

A rail-rail comparator input stage has two types of differential-pairs that have to be offset calibrated separately. This requirement complicates the addition of precision hysteresis to the rail-rail comparator because the Gm (transconductance) of the rail-rail comparator input stage varies with input common mode voltages. As a result the hysteresis voltage becomes a variable, especially when the input common mode voltage is near the middle of the voltage rails the hysteresis becomes half the value near either rail, e.g., Vdd or common (ground).

Offset calibration and precision hysteresis for a rail-rail comparator with large dynamic range


A tubular seal is formed of an elastic material and equipped on the outer periphery of a first tube. A second tube is inserted in the tubular seal and connected with the first tube via the tubular seal. A clamp is in a strap shape formed of a metallic material and is attached on an outer periphery of the tubular seal. The second tube or the clamp has a tab, which is protruded in a radial direction. The tubular seal has a slit extending in the radial direction. The tab is engaged with and latched on the slit.

Conventionally, an internal combustion engine of a vehicle is equipped with a throttle valve for controlling intake air. In a conventional structure, the throttle valve is equipped to an intake passage through which the engine draws intake air into combustion chambers. In a conventional structure, the piston of the engine produces negative pressure when drawing intake air in an intake stroke, and the negative pressure is applied to a joint portion between the intake passage and the throttle valve.
In a turbocharged engine, a throttle valve may be located on the downstream side of a compressor of a turbocharger. In this configuration, the compressor produces a positive pressure to pressurize intake air and feeds the pressurized air through an intake passage into the throttle valve. Consequently, a joint portion between the intake passage and the throttle valve may be applied with the positive pressure. Consequently, leakage is concerned at the joint portion.