A cellulosic fibrous structure, such as paper. The fibrous structure has at least three intensively distinct regions. The regions are distinguished from one another by intensive properties such is basis weight, density and projected average pore size, or thickness. In one embodiment, the fibrous structure has regions of two basis weights, a high basis weight region and a low basis weight region. The high basis weight region is further subdivided into low and high density regions so that a fibrous structure having three regions is produced.. A second embodiment is a four region fibrous structure. Two of the regions have generally equivalent relatively high basis weights and two of the regions having generally equivalent relatively low basis weights. The high basis weight regions and low basis weight regions are further subdivided according to relatively high and relatively low densities, so that when the high and low basis weight regions are permuted with the high and low density regions, four different regions result. The regions distinguished by density will have inversely proportionate projected average pore sizes.

Cellulosic fibrous structures, such as paper, are well known in the art. Frequently, it is desirable to have regions of different basis weights within the same cellulosic fibrous product. The two regions, as exhibited by paper in the prior art, serve different purposes. The regions of higher basis weight impart tensile strength to the fibrous structure. The regions of lower basis weight may be utilized for economizing raw materials, particularly the fibers used in the papermaking process and to impart absorbency to the fibrous structure. In a degenerate case, the low basis weight regions may represent apertures or holes in the fibrous structure. However, it is not necessary that the low basis weight regions be apertured.
The properties of absorbency and strength, and further the property of softness, become important when the fibrous structure is used for its intended purpose. Particularly, the fibrous structure described herein may be used for facial tissues, toilet tissue, and a paper towel, each of which is in frequent use today. If these products are to perform their intended tasks and find wide acceptance, the products must exhibit and maximize the physical properties discussed above. Tensile strength is the ability of a fibrous structure to retain its physical integrity during use. Absorbency is the property of the fibrous structure which allows it to retain contacted fluids. Both the absolute quantity of fluid and the rate at which the fibrous structure will absorb such fluid must be considered when evaluating one of the aforementioned consumer products. Further, such paper products have been used in disposable absorbent articles such as sanitary napkins and diapers.
Several attempts have been made in the art to provide efficient and economical means to manufacture paper having two different basis weights. One of the very early attempts is illustrated in U.S. Pat. No. 795,719 issued Jul. 25, 1905 to Motz, which patent discloses a Fourdrinier wire having a number of upstanding protuberances and which is passed between two rollers. One advance over Motz is illustrated by U.S. Pat. No. 3,025,585 issued Mar. 20, 1962 to Griswold, which discloses a belt having tapered projections 61 that rearrange fibers deposited thereon.
Various shapes of protuberances have been used in conjunction with papermaking machines, yielding differing basis weight regions, such as low basis weight regions of varying shapes. For example, U.S. Pat. No. 3,034,180 issued May 15, 1962 to Greiner et al. discloses protuberances which are pyramid shaped, cross-shaped, etc. Even the knuckles of a Fourdrinier wire may be utilized as upstanding protuberances, as illustrated in U.S. Pat. No. 3,159,530 issued Dec. 1, 1964 to Heller et al.
Instead of apertures, U.S. Pat. No. 3,549,742 issued Dec. 22, 1970 to Benz shows a foraminous drainage member having flow control members which project above the surface of the drainage member a distance less than the thickness of the fibrous structure formed thereon and the fibrous structure may be later densified in a hard nip. Another teaching that fiber concentrations in areas of a fibrous structure may be dispersed so that, dependent upon the length of the fibers, island areas of extremely thin cross-section may be produced is shown by U.S. Pat. No. 3,322,617 issued May 30, 1967 to Osborne.
Finally, several attempts to provide an improved foraminous member for making such cellulosic fibrous structures are known, one of the most significant being illustrated in U.S. Pat. No. 4,514,345 issued Apr. 30, 1985 to Johnson et al. Johnson et al. teaches hexagonal elements attached to the framework in a batch liquid coating process.
However, one problem present with the paper made according to each of these references is that the tensile strength of such paper is limited by the strength of the high basis weight regions of such paper. If the high basis weight regions are strengthened by adding more fibers, a noneconomical use of raw materials results.
Another problem with the paper made according to the foregoing references is that the absorbency is limited by the low basis weight regions of the paper. Because the low basis weight regions are taught to be of constant density and thickness, such paper is limited in how absorbent it will be for the user.
One explanation for the limited properties of the paper produced according to the prior art may be that such paper is produced entirely in registration with the protuberances, as taught in the aforementioned references. That is, after the fibrous slurry which forms the paper having plural basis weights is deposited on the Fourdrinier wire, all subsequent operations, such as drying, etc., are carried out in registration with the high and low basis weight regions as originally formed.
One attempt to vary the density of paper made according to the prior art is by joining two plies of the paper together and knob-to-knob embossing the resulting laminate as taught in U.S. Pat. No. 3,414,459 issued Dec. 3, 1968 to Wells. However, while this operation increases the density of the embossed areas, it . has no effect on basis weight and adds a converting step to the papermaking process.
Accordingly, it is an object of this invention to overcome such problems of the prior art and particularly to overcome such problems as they relate to a single lamina of paper. Specifically, it is an object of this invention to provide a paper which increases the tensile strength through providing a stronger high basis weight region, without substantially increasing the number of fibers utilized to make the high basis weight region. Also, it is an object of this invention to provide low basis weight regions having enhanced absorbency by providing plural densities and/or plural projected average pore sizes in such low basis weight regions. Further, it is an object of this invention to provide plural densities and/or plural projected average pore sizes without a dedicated converting operation, such as embossing. It is also an object of this invention to accomplish the foregoing without radical departure from known papermaking machinery and techniques.
The foregoing may be accomplished by carrying out steps in the process of forming the claimed cellulosic fibrous structure which comprise operations which are selectively applied to regions is of the fibrous structure, which selected regions are not coincident the regions distinguished and defined by mutually different basis weights or densities. Particularly, the step of applying a noncoincident differential pressure to the fibrous structure is useful. Such noncoincidence may occur through differences in size, pattern registration, or combinations thereof, between the originally formed plural basis weight and density regions and the regions to which a differential pressure is selectively applied.

Cellulosic fibrous structures having at least three regions distinguished by intensive properties


A D/A converter has one single input transistor used in common with a plurality of output transistors to together form current mirrors, and a decoder serves to sequentially select the current mirrors in response to a digital input, causing to generate a corresponding analog output from currents from selected ones of the current mirrors. The commonly used input transistor is centrally located with respect to the current mirrors such that the difference between the maximum and minimum distances, or that between the maximum and minimum parasitic resistances, between the input transistor used in common and the output transistors is reduced and the conversion characteristic can be improved.

This invention relates to a digital-to-analog (D/A) converter of the current cell type comprising a plurality of current mirrors and selecting means therefor. More particularly, this invention relates to such a D/A converter formed by taking into consideration the effects of parasitic resistances of conductive lines through which power is supplied to the current mirrors.
FIG. 6A shows, for illustration, the circuit structure of a prior art D/A converter of the current cell type having six current mirrors, or six pairs of transistors Tr0+Tr1, Tr0+Tr2, Tr0+Tr3, Tr0+Tr4, Tr0+Tr5 and Tr0+Tr6, and a decoder (selecting means) 3 for decoding a digital input D and generating and outputting selection signals to the current mirrors. As an analog output A is generated corresponding to the digital input D by totaling output currents from those of the transistors Tr1-Tr6 selected by the selection signals, output currents i1-i6 of the plurality of current mirrors are selected to form the analog output A according to the digital input D.
Explained more in detail, transistor Tr0 is a MOS transistor on the input side of the current mirrors, its drain being connected to a power source line 1, its source being connected to a constant current source 2 for a reference current i0 and its gate being connected to the gates of the transistors Tr1-Tr6. In other words, transistor Tr0 serves as an input transistor for providing a constant reference current.
Transistor Tr1 is a MOS transistor on the output side of one of the current mirrors. Its drain is connected to the power source line 1, and its source, through which mirror current i1 flows, is connected through a switch SW1 to an output line for the analog output A. Transistor Tr2, too, is a MOS transistor on the output side of a current mirror, its drain being connected to the power source line 1 and its source, through which mirror current i2 flows, being connected through another switch SW2 to the output line for the analog output A. The other transistors Tr3-Tr6 may be similarly described, each being a MOS transistor on the output side of a corresponding current mirror, the drain of each being connected to the power source line 1 and the source of each being connected through a corresponding one of switches SW3-SW6 to the output line for the analog output A and having a corresponding mirror current i3, i4, i5 or i6 to flow therethrough. In summary, transistors Tr1-Tr6 are all transistors on the output side, having the same transistor (Tr0) in common on the input side. The aforementioned plurality of pairs of transistors Tr0+Tr1, Tr0+Tr2, Tr0+Tr3, Tr0+Tr4, Tr0+Tr5 and Tr0+Tr6 form a partially overlapping plurality of current mirrors, and their output currents i1-i6 may or may not be included in the analog output A, depending on whether the corresponding switches SW1-SW6 are in the conductive or closed (ON) condition or in the cut-off or open (OFF) condition.
The decoder 3 serves to switch on by simple means a suitable number of the switches SW1-SW6 corresponding to the digital input D while the selection signals to the current mirrors, or their ON and OFF conditions, are controlled. As the value of the digital input D increases from "0" sequentially to "1", "2", "3", "4", "5" and "6", for example, the decoder 3 switches on switches SW1, SW2, SW3, SW4, SW5 and SW6 from OFF to ON positions at each of the corresponding points in time. Similarly, when the value of the digital input D decreases, these switches are switched off from the ON to OFF positions in the reverse order. In other words, the decoder 3 usually selects the output transistors in the order of their proximity to the input transistor Tr0 when the digital input D increases (and in the reverse order when the digital input D decreases).
If each current mirror of such a D/A converter functioned ideally, the currents i1-i6 would be all equal, and the current values i1, i1+i2, i1+i2+i3, . . . , i1+i2+i3+i4+i5+i6 of the analog output A corresponding to the values of digital input D "0", "1", "2", . . . "6" would form a step function curve with equal steps, as shown by two-dot dashed line in FIG. 6B. In the case of a D/A converter of a similar structure with an increased number of current mirrors corresponding to an increased number of bits for the digital input D, the input-output curve would become a straight line with a constant slope, as shown by a two-dot dashed line in FIG. 6C.
In reality, however, the power source line 1 has parasitic resistance and the current which flows therethrough is fairly large. Thus, unless the resistance of the power source line 1 can be reduced to a negligible level, the conversion characteristic of the D/A converter is significantly different from the ideal situation described above.
What is herein referred to as the power source line 1 actually includes not only the line from the power supply terminal of the source voltage Vdd to the transistor Tr0 on the input side but also the first branch line branching therefrom and reaching the first transistor Tr1, the second branch line branching from the first branch line and reaching the second transistor Tr2, and so on to the last branch line branching from the penultimate branch line and reaching the last transistor Tr6. In other words, resistances Ra-Rf and R0-R6 are parasitically distributed among the lead lines as shown in FIG. 6A such that the currents i1-i6 are not all equal but tend to sequentially decrease, or i1>i2>i3>i4>i5>i6. As a result, the input-output characteristic of such a D/A converter is usually a step function curve with unequal steps (as shown by a solid line in FIG. 6B). In the case of such a D/A converter with an increased number of bits for the digital input D, the deviation from the ideal situation becomes greater as the value increases as shown by a solid line in FIG. 6C.
Japanese Patent Publication Tokkai 7-154260 disclosed a method of counteracting such ill effects of parasitic resistances in conductive lines. According to this technology, the power source terminal and each conductive line are duplicated such that the output currents from the individual current mirrors can be uniformized and a layout is made such that the sums of the lengths of the paths will become equal.
This method, however, cannot solve the problem for all cases because there are situations wherein it is difficult to duplicate the power source terminal or the conductive lines. There may also be situations wherein, although such duplication is not impossible to carry out, it is still not desirable to increase the number of power source terminals or the area for the wiring or the layout of the wiring may be difficult. Thus, it is not desirable to resort to such a conventional duplication method just in order to counteract the ill-effects of parasitic resistances of the conductive lines on the conversion characteristic.
For D/A converters to be mounted to an LSI circuit, limitations on the design become severer regarding the number of terminals, the area for the wiring and the layout as a whole because LSI circuits are requires to be miniaturized and highly integrated.

Digital-to-analog converter with current source centrally located between a plurality of current mirrors


A method of determining a local causal neighborhood of a target variable from a data set can include identifying variables of the data set as candidates of the local causal neighborhood using statistical characteristics, and including the identified variables within a candidate set. False positive variables can be removed from the candidate set according to further statistical characteristics applied to each variable of the candidate set. The remaining variables of the candidate set can be identified as the local causal neighborhood of the target variable.

1. Technical Field
The present invention relates to data processing and analysis and, more particularly, to causal discovery and feature selection for classification.
2. Description of the Related Art
Advances in computing technology have allowed researchers across many fields of endeavor to collect and maintain vast amounts of observational statistical data such as clinical data, biological patient data, data regarding access of web sites, financial data, and the like. Using computational methods, these data can be processed in order to learn to classify a particular target variable of interest. For example, a patient can be classified into a high or low risk group given his or her demographic data, historical data, lab tests, etc.
As only recently proved, under certain conditions the observational statistical data also can be processed to induce causal relations among the observed quantities, also referred to as variables or features. For example, by processing such observational statistical data, it can be induced that smoking probabilistically causes lung cancer, that the placement of an item in a grocery store increases sales, or that increasing the amount of vacation time provided to factory workers increases productivity. Notably, the aforementioned causal relationships are induced without controlled experiments. See Spirtes, P., C. Glymour, and R. Schemes, Causation, Prediction, and Search, Cambridge, Mass., London, England: The MIT Press (Second ed. 2000).
While some of these data sets may include only 10–100 or so variables, others can include upwards of hundreds of thousands of variables. Within data networks of thousands of variables, variable selection—that is the identification of a minimal, or close to minimal, subset of variables that best predicts the target variable of interest—can be difficult. The identification of the relevant variables that best predict a target variable, however, has become an essential component of quantitative modeling, data-driven construction of decision support models, and computer-assisted discovery.
Similarly, the identification of the variables that directly cause or are caused by the target variable is difficult. In this context, if A is said to directly cause B, no other variables from the set of observed variables in the data causally intervene between A and B. The problem of identifying a causal neighborhood around the target variable, that is variables that are directly caused or cause the target variable, is referred to as local causal discovery. The identification of all direct causal relations among all variables is referred to as global causal discovery. The identification of the direct causes and direct effects of the target variable is extremely important with respect to manipulating various systems. For example, in order to build a drug to treat a disease, one needs to know what causes the disease, not simply how to predict or diagnose the occurrence of the disease (i.e., classify the patient as having the disease or not).
The problem of variable selection for classification in biomedicine has become more pressing than ever with the emergence of such extremely large data sets. The number of variables in these data sets, as noted, can number into the hundreds of thousands, while the sample-to-variable ratio of the data sets remains small in comparison. Such data sets are common in gene-expression array studies, proteomics, and computational biology, for example where one attempts to diagnose a patient given as variables the expression levels of tens of thousands of genes, or the concentration level of hundreds of thousands of protein fragments. With regard to medical diagnosis, the identification of relevant variables, for example as derived from lab tests, for a particular condition can help to eliminate redundant tests from consideration thereby reducing risks to patients and lowering healthcare costs. Similarly, in biomedical discovery tasks, identification of causal relations can allow researchers to conduct focused and efficient experiments to verify these relations.
Other domains such as text-categorization, information retrieval, data mining of electronic medical records, consumer profile analysis, and temporal modeling share characteristics with the aforementioned domains. In particular, these domains also have a very large number of variables and a small sample-to-variable ratio. Identifying a reduced but still predictive variable set can significantly benefit computer, statistical, and paper-based decision support models pertaining to these fields in terms of understandability, user acceptance, speed of computation, and smoother integration into clinical practice and application in general.
The theory of causal discovery from observational data is based on Bayesian Networks, specifically a special class of Bayesian Networks, known as Causal Bayesian Networks, or Causal Probabilistic Networks (CPNs). In a causal Bayesian Network, an arc (edge) from a variable A to a variable B, means that A is causing B. The same theory also can be used for solving variable selection problems. Bayesian Networks are mathematical objects that capture probabilistic properties of the statistical data. One component of a Bayesian Network is a graph of causal relations depicting that A is directly causing B. Further details regarding Bayesian Network theory are provided in Neapolitan, R. E., Probabilistic Reasoning in Expert Systems. Theory and Algorithms, John Wiley and Sons (1990).
Bayesian Networks provide a useful tool for analyzing large data sets derived, for example, from the aforementioned domains. More particularly, Bayesian Networks provide a conceptual framework for problem solving within areas such as prediction, classification, diagnosis, modeling, decision making under uncertainty, and causal discovery. As such, Bayesian Networks have been the subject of a significant amount of research which has yielded a variety of analysis tools and techniques.
Still, known techniques for inducing a Bayesian Network, and thus the causal relations, from statistical data and determining the relevant variables for the prediction of a target variable are limited. That is, known techniques for determining which variables influence a selected target variable are limited to operating upon data sets having only several hundred variables at most. Such conventional techniques are unable to scale upward to effectively process data sets having more than several hundred variables. Accordingly, conventional Bayesian Network analysis techniques are not able to work effectively upon larger data sets such as those derived from gene-expression array studies, proteomics, computational biology, text-categorization, information retrieval, data mining of electronic medical and financial records, consumer profile analysis, temporal modeling, or other domains.

Method, system, and apparatus for casual discovery and variable selection for classification


In a sliding contact having a base made of an elastic material and a precious metal contact connected to the base, the base extends along a sliding face, and the precious metal contact is connected to the base in the almost vertical direction with respect to the contact position of the precious metal contact and the sliding face by beam welding.

1. Field of the Invention
The present invention relates to a sliding contact and a method of producing the contact.
2. Description of the Related Art
A well-known type of a sliding contact of an encoder for used in what is called a mouse and the like is shown in FIGS. 10(a) and 10(b). Such a sliding contact has a support 2 for moving above a resistor 1 (a pulse switch substrate may be used instead of the resistor) in the direction indicated by the arrow. A relatively wide base 3 made of an elastic material is supported by the support 2. The leading end of the base 3 is extended toward the resistor 1, and connected to an abrasive-resistant precious metal contact 4 in contact with the resistor 1 by, for example, welding. The precious metal contact 4 is formed by fixing fine wires 4a, each having a folded portion in contact with the resistor 1 at its end and a portion in contact with the base 3 at its other end, onto a linear plate 4b by electric resistance welding.
FIGS. 10(c) and 10(d) show another type of sliding contact having a construction which is basically similar to that of the contact shown in FIG. 10(a). In this case, the portion in contact with the resistor 1 is specially devised in its shape.
However, the above sliding contacts of the prior art have the following problems:
(1) Since the precious metal contact 4 has, at its end, the folded portion in contact with the resistor 1 and the fine wires are arranged in a row, the processing of the contact 4 is troublesome.
(2) The precious metal contact 4 needs a sufficient contact area in order to prevent the contact portion from falling due to the pressure when the other end of the precious metal contact 4 abuts against the resistor 1 located in the extending direction of the base 3. The length of the base 3 is thereby shortened. The base 3 is made of an elastic material, and the shortening of the base 3 hinders free deformation of the base 3, thereby making the pressure of the precious metal contact 4 against the resistor 1 unstable and lowering reliability of the precious metal contact 4.
(3) Since the precious metal contact 4 is formed with wires, there are many useless portions except for the contact point, and thus the cost is high. Furthermore, although the precious metal contact 4 is given a function for stabilizing the pressure by being made of an elastic precious metal and lengthened in order to solve the problem (2), the material of the contact 4 is limited to specific precious metals, and the amount of the used precious metal is increased, thereby increasing the cost.
(4) Since the assembling of the precious metal contact 4 and the connection of the precious metal contact 4 and the base 3 are performed by welding, the welding process takes much time. Furthermore, since the precious metal contact 4 is formed with wires as described above, it is necessary to take special trouble in positioning the precious metal contact 4 during the welding process.

Method for manufacturing slide electrical contact


A self-powering tamper detection system architecture includes a power source, a tamper detector configured to identify a tamper event, a tamper switch electrically connected to the power source and mechanically connected to the tamper detector, a tamper controller configured to produce a tamper response when the tamper event is identified, and program memory configured to store program data. The tamper detector is configured to mechanically actuate the tamper switch when a tamper event occurs, and the tamper response provides a disruption of the program data. The tamper detector and the tamper switch can include printed circuit board and embedded transformer, whereby the embedded transformer includes an axially-moveable ferromagnetic core.

The present disclosure relates to tamper detection systems, and more particularly, to a self-powering tamper detection and response system architecture for electronic circuitry.
The protection of critical information contained on printed circuit boards from unwanted access is necessary to ensure the integrity of components and systems in which those circuits can reside. For example, sensitive program data that can be stored in circuitry must not be accessed by unauthorized persons, competitors, or adversaries. In some situations, the unauthorized tampering of program data can affect the proper functioning of a component. In other situations, the unauthorized access of program data can pose a risk to competitive advantage and/or national security. Multiple levels of security can often be used to prevent the unauthorized access to program data, but as a final measure of security, an electronic component may have a means of detecting when unauthorized tampering is occurring. When a tampering event is triggered, an electronic component is instructed to erase or disrupt the stored program data so that the data cannot be accessed by an unauthorized party.
Several anti-tamper systems have been developed to achieve the goal of detecting and responding to a tampering event. For example, U.S. Pat. No. 9,798,902, to Ludlow, discloses anti-tamper sensors involving transducers. Tamper detection systems involving transducers are known in the art, whereby a transducer utilizes the conversion of one form of energy into another to achieve a response. For example, U.S. Pat. No. 8,499,173, to Caci, discloses a light emitter, a light receiver, and a reflector for detecting tampering on a circuit board. Tamper detections have also been developed to detect tampering on consumer electronics products, which can be useful for products that are under a manufacturer's warranty. For example, U.S. Pat. No. 8,736,286, to Johnson, discloses a means of detecting consumer abuse without having to rely upon the explanatory statements of the user who may be returning a unit that is no longer working according to the original specification of the manufacturer.

Self-powering tamper detection and response system architecture


An electric power steering apparatus includes a speed reducing mechanism for decelerating the rotation of a rotatable shaft in an electric motor and a converting mechanism for converting the output rotation of the speed reducing mechanism into the axial movement of a steering shaft extending toward the right and left sides of a vehicle. The speed reducing mechanism includes an input pulley driven by the electric motor, an output pulley arranged with the steering shaft enclosed thereby, a belt for connecting the input pulley and the output pulley to each other, and a belt tension adjuster.

1. Field of the Invention
The present invention relates to an electronic power steering apparatus that generates a steering assist force by an electric motor.
2. Description of Related Arts
In a rack assist type electronic power steering apparatus, the rotation of an electric motor is decelerated through a pulley/belt mechanism, and is then converted into the axial movement of a rack shaft through a screw ball mechanism enclosing a rack shaft (see JP-B-4-28583, for example).
In this case, a belt is interposed in a power transmission path between the electric motor and the rack shaft. Accordingly, a shock load and vibration from the rack shaft are not transmitted to the electric motor.
However, vibration may be generated in the belt due to fluctuations in the tension of the belt, and transmitted to a housing to propagate into a vehicle chamber, to be noise.


An Internal Combustion Engine including a plurality of reciprocating pistons disposed about the periphery of a central housing, and a pair of drive cams responsive to the displacement of the pistons for driving one or more output drive shafts. A piston rod cross member engages cam raceways of a pair of drive cams. Each raceway comprises a plurality of lobes defining power and compression stroke surfaces. Axial displacement of the cross member within the raceway effects rotation of the drive cams and output drive shafts which are rotational coupled to each drive cam. The drive cams and output drive shafts may rotate in the same or opposite directions, delivering high torque at low rotational speeds and, in one embodiment providing a torque-balanced output. Furthermore, the drive cams may include peripheral teeth for driving a timing gear which is timed relative to the output drive shafts for driving auxiliary equipment.

Designers of power output devices, e.g., automobile, aircraft and locomotive engines, are faced with a myriad of competing design criteria that result in various design compromises. For example, if it is desirable to optimize power output, a compromise in engine torque is often necessary. Similarly, if one desires optimal energy conversion, e.g., specific fuel consumption, a designer must choose an appropriate air-standard combustion cycle to match this requirement. In yet other examples, if it is desirable to optimize horsepower and torque, one may need to accept weight and/or fuel consumption penalties.
While there are literally thousands of internal combustion engine designs and variations thereof, all employ certain fundamental or basic principles. These include the intake of a combustible mixture, e.g., oxygen and gasoline, into a working area, compression of the combustible mixture, ignition of the mixture to effect its expansion, capturing the energy of the expansion to produce work, and expelling combustion by-products into an exhaust system so as to prepare the working area for a subsequent cycle.
Internal Combustion Engines (ICEs)
Commercially successful internal combustion engines include reciprocating-piston, rotary, and gas-turbine engines. Following is a brief discussion of each followed by the advantages and disadvantages of each. Applications of each are also discussed.
Traditional reciprocating internal combustion engines employ the reciprocating motion of a piston/cylinder to perform the functions described above. Linear motion of the piston is translated into rotational motion by means of a piston rod that is articulately mounted to the underside of the piston at one end thereof and pivotally mounted at the other end to an eccentric portion of a crankshaft. Generally, these internal combustion engines employ the Carnot two-stroke, Otto four-stroke or Diesel two and/or four-stroke air-standard cycles.
The Carnot two-stroke engine typically employs a piston/cylinder arrangement wherein the cylinder comprises inlet and exhaust ports located on opposite sides of the cylinder walls. The inlet port is located slightly above the lowest point of piston travel, e.g., bottom dead center, and the exhaust port is located on the opposing side about a midpoint relative to piston travel. The combustible mixture is first introduced into the cylinder chamber as the piston uncovers the inlet port. The downward motion of the piston from the prior stroke, causes the combustible mixture (located within the housing) to be pressurized thus being forced into the cylinder chamber. As the piston moves upwardly and past the exhaust port, the combustible mixture is compressed and ignited upon reaching the top of the piston's stroke, i.e., top dead center. The expansion of the combustible mixture produces a downward power stoke and, upon passing the exhaust port, begins to be expelled from the cylinder chamber. As the piston travels downward yet further, the combustible mixture is pressured by the underside of the piston (traveling downwardly) and is injected into the cylinder as the piston passes the inlet port. This injection of newly-introduced combustible mixture further augments the expulsion of exhaust gases through the exhaust port. The Carnot two-stroke produces a power stroke for every two strokes of the piston, or once per revolution, i.e., of the drive shaft.
The Otto four-stroke engine typically employs a piston/cylinder arrangement wherein the inlet and exhaust ports are located at the top or uppermost portion of the cylinder and are operated, i.e., opened and closed, by means of cam-driven valves. The combustible mixture is first introduced upon opening the inlet port whereby the downward motion of the piston generates a vacuum for drawing the combustible mixture into the cylinder. The next stroke is the compression stroke, wherein the inlet and exhaust valves are both closed and the combustible mixture is compressed as the piston traverses upwardly. At or near the top of the piston stroke, the air-gas mixture is ignited thus initiating its expansion and downward motion of the piston. Upon completion of the downward or power stroke, the exhaust port is opened such that the subsequent upward stroke of the piston expels the combusted gases outwardly into an exhaust manifold. The Otto four-stroke cycle produces a power stoke for every four stokes of the piston, or once every two revolutions of the drive shaft.
More recent innovations include the Wankel Rotary engine which employ the eccentric motion of a polygonal-shaped rotor within a substantially elliptically-shaped, or more accurately, a epitrochoidally-shaped housing or chamber. The apexes of the polygonal-shaped rotor create discrete chambers which, upon rotation of the rotor within the housing, pass inlet ports, ignition spark plugs and exhaust ports. More specifically, as the rotor passes the inlet port, the combustible mixture is introduced within one of the chambers. As this chamber rotates approximately 90 degrees, the mixture is compressed against a wall of the epitrochoidally-shaped housing. Ignition or spark plugs are located at this angular position and, upon ignition, the combustible mixture expands causing the rotor to be driven approximately 120 degrees within the housing. An exhaust port is located at the next rotational position and the combusted gases are expelled from the chamber. Similar to the compression stage of the Wankel cycle, the chamber is caused to be reduced in volume, i.e., against the wall of the epitrochoidally-shaped housing, thereby expelling the exhaust gases outwardly.
In conventional turbine engines, a compressor section is used to compress air into a combustion chamber. Fuel is introduced into the chamber and ignited to expand the air-gas mixture. Turbine vanes capture the energy of the expanded air-gases to turn a turbine shaft which also drives the compressor section to continue the combustion cycle. Generally, this form of internal combustion engine employs the Brayton air-standard cycle. From its brief description, it will be appreciated that the turbine engine is, perhaps, the most elegant, however, it too has disadvantages which limits its application.
Advantages/Disadvantages & Practical Applications of Reciprocating Piston ICEs
The following is a brief examination of reciprocating piston ICEs in terms of their properties, performance, and practical applications. Inasmuch as the Wankel rotary and turbine engines are not widely employed or have specific/limited applications, these will only be mentioned in terms of there need for gear reduction apparatus to lower output velocities to useable speeds. Furthermore, these engine designs represent a significant departure from the elements and teachings of this invention.
A two stroke air-standard cycle (or Carnot Cycle) delivers a power stoke with each revolution as compared to the four-stroke cycle which delivers a power stroke with every two revolutions. Consequently, reciprocating ICEs employing a two stroke cycle can deliver twice the power of a four stroke. Two stroke engines do not require valves and the associated mechanisms for the intake of fuel and exhaust of combusted gases. Four stroke engines, on the other hand, require a complex array of cam-driven valves for intake and exhaust. ICEs employing a two stroke cycle can operate at any orientation, which can be important in applications wherein the powered-vehicle or device pitches or rolls such as an acrobatic fixed-wing aircraft, helicopter or chainsaw. Engines employing a four-stroke cycle require that oil be delivered from a gravity-based sump. Consequently, four stroke engines typically are designed with the forces of gravity in mind. Two-stroke engines, therefore, offer simplicity and a significant power-to-weight ratio as compared to many four-stroke engine designs.
Disadvantages of the two-stroke air-standard cycle generally involve wear, fuel efficiency and pollution. The lack of a dedicated lubrication system typically results in a high rate of component wear. Further, two-stroke reciprocating engines, which employ a conventional crankshaft, also experience accelerated wear of the piston. To better understand this phenomena, it should be appreciated that the eccentricity of the crankshaft causes the piston rod to be oriented off-axis relative to the piston/cylinder axis. As such, a lateral component of the resultant force vector imposes high frictional forces between the piston and cylinder. Consequently, the piston rings wear, pressure is reduced i.e., causing blow-by, and fuel efficiency decreased. Other disadvantages are simply due to the way fuel is burned (or not burned) in two stroke engines. For example, the exhaust phase of the cycle is, at least in part, combined with the fuel intake and compression phase of the cycle. Consequently, exhaust gases are intermixed with a fresh charge of air-gas, hence, the mixture for ignition is non-optimum, i.e., contaminated by exhaust gases from the previous stroke. Similarly, inasmuch as the intake and exhaust occur nearly simultaneously, but along opposite sides of the cylinder, fresh fuel may be exhausted before ever being compressed and ignited. Consequently, two-stroke engines are not highly fuel efficient.
The principle advantage to a four stroke air-standard cycle (or Otto cycle) relates to fuel efficiency. More specifically, four stroke engines employ a stroke entirely dedicated to the exhaust of combusted gases, hence, four stroke engines burn cleaner and more efficiently that two stroke engines. That is, combusted gases do not intermix with a fresh charge of air-fuel in or during the compression/ignition stroke. Furthermore, four-stroke engines can have independent/dedicated oil and fuel reservoirs, i.e., do not use a gas-oil mixture, hence four stoke engines experience less wear and are less costly to operate.
The disadvantages of four stroke engines have been discussed above, i.e., when being compared to a two stroke engine, however, suffice it to say that four stroke engines deliver significantly less power output than two stroke engines.
Diesel two and four stroke cycles have the same advantages and disadvantages as those discussed above in connection with the Carnot and Otto air-standard cycles. Diesel engines do, however, allow high compression ratios inasmuch as the flash point (i.e., the temperature at which the fuel ignites) of Diesel fuel is substantially higher than conventional gasoline fuel. While this can offer the advantage of high power output, Diesel fuel contains less energy than gasoline (on a BTU/in3 or volumetric basis) and does not produce the same power output when compared to gasoline bumming engines. Generally, the advantage of Diesel engines relates to the low cost of Diesel fuel and the relatively high efficiency with which it burns.
All of the above air-standard cycles and engine designs operate efficiently at relatively high rotational speeds. For example, a gas turbine engine is typically efficient at about ten-thousand (10,000) RPM. Four-stroke automobile engines are efficient within a range of about fifteen hundred to three thousand (1,500 to 3000) RPM. This is also true for the Wankel rotary engine. Typically, such rotational velocities are orders of magnitude above useful speeds to, for example, drive automobile tires, helicopter rotors, ship propellers etc. Consequently, all require speed reduction devices, e.g., transmissions, to lower and control the speed of output drive shafts. It will be appreciated that such devices add significant weight, require periodic maintenance, and are costly to fabricate, operate and maintain.
Other disadvantages of ICEs of the prior art relate to the weight distribution of conventional designs and to a lack of balanced torque output. With respect to the former, the center of gravity (C.G.) of prior art ICEs is frequently offset with respect to the output shaft axis. While this does not present difficulties in many applications, in other applications, such as a compound helicopter, it is beneficial to have the engine C.G coincident with the output drive shaft axis. For example, helicopters typically are designed such that the turbine engines are juxtaposed relative to the helicopter transmission. Despite the output orientation of the turbine engine (which faces forward), a rather elaborate bevel gearing system is employed to ensure that the center of gravity of the turbine engine lies in the same plane (normal to the longitudinal axis of the helicopter). As such, this drive-train configuration is non-optimal in terms of weight and is highly mechanically complex.
With respect to the latter, helicopters typically employ anti-torque devices to counter-act the torque developed in the fuselage as a result of the high torque required to drive the main rotor system. Conventional anti-torque devices employ tail rotors or propulsive thrusters to generate a force vector equal and opposite to the engine-generated moment vector, i.e., at a calculated distance from the rotational axis. As such these devices, which include tail cone structure, tail drive shafts, tail rotor gearboxes also add unnecessary weight.
A need, therefore, exists for an ICE which maximizes energy conversion, eliminates the need for intermediate speed reduction devices, e.g., speed reducing transmissions, improves performance, enhances reliability, reduces weight and minimizes mechanical complexity.

High torque, low velocity, internal combustion engine


A water-soluble prolamin composition, such as a zein composition, and methods for producing the same. A method for tagging items comprising applying a plurality of non-coding DNA tags in a prolamin composition, such as a zein composition, wherein the selection of the particular taggants corresponds with a binary or nonbinary code sequence containing information about the tagged items.

Prolamins are plant proteins having a high proline amino acid content. Applications that require even dispersion of prolamin, such as where it is combined with sequences of non-coding DNA in the form of combinations of DNA taggants applied to food products in a supply chain, often require that the prolamin not aggregate into clumps. One approach is to dissolve the prolamin-based taggants in solution and apply the solution to the food products, allowing the solvent to evaporate and leave well-distributed food-safe taggants on the food products.
Prolamins are typically insoluble in water but are soluble in water-ethanol mixtures and so applications that require a prolamin in solution often involve the use of ethanol although ethanol might be disfavored as a solvent in many environments. But one issue with using ethanol in an industrial process is its flammability.
There is a need for a method to produce stable, discrete zein particles, which are capable of aqueous dispersion.

Water-soluble prolamin, preparation thereof, and uses thereof for food-grade application including prolamin compositions combining prolamin and DNA taggants


An adjustable golf cup providing multiple cup diameters, a puttable upper surface, and advertising opportunity.

It is estimated that the modern game of golf originated in 15th-century Scotland and has continued to grow into a popular sport that is widely played both on the amateur level and on the professional level. Currently, the game is played by approximately 25 million people in the United States and approximately 60 million people worldwide. There are approximately 17,600 golf courses in the United States and approximately 35,000 golf courses worldwide.

Adjustable golf cup with puttable surface


A disclosed method may include (1) receiving, at a local gateway device included in a network, a query message that initiates a topology discovery process from a remote gateway device included in the network, (2) identifying, within the query message, at least one characteristic of a first interface included on the remote gateway device, (3) selecting, for the first interface, a second interface included on the local gateway device based at least in part on the characteristic of the first interface identified within the query message, and then (4) sending, to the remote gateway device, a response message that (A) includes at least one characteristic of the second interface included on the local gateway device and (B) enables the remote gateway device to map the first interface to the second interface in connection with the topology discovery process. Various other apparatuses, systems, and methods are also disclosed.

In today's world, uninterrupted Internet connectivity has become essential for many gateway and/or enterprise users. Gateway devices are often used to forward traffic within a network and/or across networks. These gateway devices may represent and/or form part of the essential infrastructure of such networks. In some examples, a set of gateway devices may each include and/or house various access interfaces. In such examples, these access interfaces may each be assigned to and/or provisioned for certain subscribers of a service provider that manages the set of gateway devices.
Unfortunately, such gateway devices may occasionally experience downtime for one reason or another. For example, a power outage may limit the amount of power that is available to a data center that houses various gateway devices in connection with the service provider. As a result, the subscribers whose traffic is forwarded by the access interfaces included in those gateway devices may be left—at least temporarily—without Internet connectivity unless the service provider is able to offer geographical redundancy.
The instant disclosure, therefore, identifies and addresses a need for additional and improved apparatuses, systems, and methods for topology discovery across geographically redundant gateway devices.

Apparatus, system, and method for topology discovery across geographically redundant gateway devices


A computerized system and method of teaching spelling interfaces with an application that captures a user's misspelled words and adds them to a word database. A teacher or instructor may also add words to the word database based on a user's curriculum, cross-curriculum or words of interest. The words in the word database are utilized to automatically create an individualized spelling teaching assignment and spelling Journal for a user. The user corrects any spelling mistakes that he or she has made and performs assignments with new words including hearing the words pronounced, spelling the words and writing sentences using the words. Spelling tests are also assigned. The teacher or instructor monitors the completion of the various assignments by the students and also monitors how well the assignments are performed.

Spell checking programs are well known. These programs work in conjunction with various computer-based programs such as word processors, e-mail programs, web page generation programs and the like, to provide built-in spell checking functions to assist the user in creating correctly spelled documents. Unfortunately, however, users and especially children or those for whom English (or other language) is a second language, have come to rely more and more on these programs with a corresponding decline in people's ability to correctly spell words. This is particularly true for students. Students would rather rely on spell checking to correct their errors than to learn how to properly spell words.
Computer programs that aim to teach students how to spell are also known. These programs, however, typically provide spelling lessons using "canned" words—that is, words that the program or teacher has chosen to present to the student. The words that are chosen to be taught to the student have no bearing or connection with the words that the student selects to use in his or her own writing.
Accordingly, a need exists for a system and method which will capture a user's misspelled words while a user is engaged in authentic writing, and allow those words to be used in a teaching application and/or in a spelling journal type of application whether alone, or with other words as directed by an instructor.

This patent is subject to a terminal disclaimer.


Only a region where TFTs constituting a high-performance circuit will be disposed in a precursor semiconductor film PCS on an insulating substrate GLS with an insulating layer UCL serving as an undercoat is irradiated with a first energy beam LSR so as to be poly-crystallized while growing crystal grains laterally. Further a second rapid thermal treatment is performed all over the panel so as to reduce defects in the crystal grains in a region PSI poly-crystallized by the aforementioned energy beam. Thus, a high-quality polycrystalline semiconductor thin film serving as TFTs for a high-performance circuit and having a high on-current, a low threshold value, a low variation and a sharp leading edge characteristic is obtained. Concurrently, the precursor semiconductor layer in the other region is poly-crystallized by the second rapid thermal treatment so as to obtain a low-quality polycrystalline semiconductor thin film serving as pixel circuit TFTs and having a low on-current and properties of a low leak current and a high withstand voltage due to its high resistance. Accordingly, it is possible to form polycrystalline semiconductor TFTs high in driving performance and TFTs having properties of a low leak current and a high withstand voltage concurrently on one and the same insulating substrate.

Thin film transistors (TFT) whose channels are formed out of polycrystalline semiconductors have been developed as pixels and pixel drive circuit devices in image display devices such as active matrix type liquid crystal displays or organic/inorganic EL displays, or image sensors. The polycrystalline semiconductor TFTs are advantageous due to their high driving capacity as compared with other drive circuit devices. Thus, peripheral drive circuits can be mounted on one and the same glass substrate together with pixels. As a result, it can be expected to customize circuit specification, to reduce the cost due to simultaneous progress of a process for designing pixels and a process for forming the pixels, or to increase the reliability due to avoidance of mechanical vulnerability in a connection portion between a drive LSI and each pixel. The displays will be also referred to as display devices or image display devices herein.
Polycrystalline semiconductor TFTs for a liquid crystal display are formed on a glass substrate in order to reduce the cost. In a process for forming the TFTs on the glass substrate, the heat resistance temperature of the glass defines the process temperature. An ELA (Excimer Laser Annealing) method for melting and recrystallizing a precursor semiconductor layer with an excimer laser has prevailed as a method for forming a high-quality polycrystalline semiconductor thin film without thermally damaging the glass substrate. The driving capacity of a polycrystalline semiconductor TFT obtained in this method is improved to be 100 or more times as high as that of a TFT whose channel is made of an amorphous semiconductor and which has been used in a background-art liquid crystal display. It is therefore possible to mount a part of circuits such as drivers on the glass substrate. In order to mount higher-performance integrated circuits, however, it is necessary to realize polycrystalline semiconductor TFTs having higher driving capacity.
As a method for forming polycrystalline semiconductor TFTs having higher driving capacity, for example, there is a method in which a semiconductor thin film is scanned relatively with a CW laser beam continuously outputting energy or a pulsed laser beam with a longer time than that in the ELA method, so that the semiconductor thin film is irradiated with an energy beam outputting energy continuously or for a fixed time, as disclosed in Non-Patent Document 1 or Non-Patent Document 2. When the melting time of a semiconductor layer is prolonged, crystal grains are grown in the laser scanning direction. Thus, it is possible to obtain a polycrystalline semiconductor thin film having a large crystal grain size and a uniform grain width and having a flat surface. Hereinafter, growth of crystal grains substantially in the laser scanning direction will be also referred to as lateral growth.
As disclosed in Non-Patent Document 3 or Non-Patent Document 4, repetitious multistage irradiation with a pulsed laser beam with a short time as in the ELA method may be performed with the irradiation position being shifted while scanning with the laser. Thus, crystal grains produced by laser irradiation in the first stage are used as nuclei so that crystals are grown laterally. When the crystals are connected with one another, it is possible to obtain a polycrystalline semiconductor thin film having a large crystal gain size in the laser scanning direction and a uniform grain width.
Polycrystalline semiconductor TFTs manufactured in these background-art methods have driving capacity in their N channels two or three or more times as high as that of polycrystalline semiconductor TFTs manufactured by an excimer laser. Thus, more peripheral drive circuits can be mounted on one and the same glass substrate together with pixels.
Non-Patent Document 1: International Electron Devices Meeting (Washington D.C., 2001) pp. 747-751
Non-Patent Document 2: Society For Information Display International Symposium Digest 2002 pp. 158-161
Non-Patent Document 3: Society For Information Display International Symposium Digest 2004, pp. 868-871
Non-Patent Document 4: IEEE Electron Device Letters vol. 19 1998 pp. 306-308
Patent Document 1: JP-A-2004-22648
In a polycrystalline semiconductor thin film grown laterally as typified by Non-Patent Documents 1 to 4, crystal grain boundaries are formed substantially in parallel with the growing direction. On the other hand, in a polycrystalline semiconductor thin film formed in the ELA method according to the background art, crystal grain boundaries have random directions. The crystal grain boundaries behave as inhibitors of electric conduction. When the current direction is parallel to the laterally growing direction in the former polycrystalline semiconductor thin film, the crystal grain boundaries are no longer primary inhibitors of electric conductions but show a good electric conduction characteristic. However, the crystal grains are not single crystals in a strict sense but contain many crystal defects such as dislocations, stacking defects, point defects, etc. Of these crystal grains, there are some serving as inhibitors of electric conductions.
As crystal grain boundaries often observed in a polycrystalline semiconductor thin film grown laterally, small crystal grain boundary groups each composed of three or more linear crystal grain boundaries arranged in parallel with one another and in an interval not larger than 100 nm are distributed. According to the ELA method, the effect of crystal grain boundaries inhibiting electric conduction is so great that these small crystal grain boundary groups as inhibitors do not manifest themselves. However, in a polycrystalline semiconductor thin film grown laterally, the small crystal grain boundary groups become one of main factors in deterioration of the characteristic of polycrystalline semiconductor TFTs and in increase of variation among the devices. For this reason, the performance of the polycrystalline semiconductor TFTs is not equal to the performance of mono-crystalline semiconductor TFTs, so that circuits the polycrystalline semiconductor TFTs can constitute are limited.
In order to mount drive circuits or peripheral circuits (hereinafter also referred to as peripheral drive circuits) on one and the same glass substrate together with pixels, TFTs having different specifications have to be formed on the same glass substrate together. For example, in a liquid crystal display device, TFTs constituting a pixel circuit thereof have to satisfy properties of a low leak current and a high withstand voltage. On the other hand, TFTs constituting a peripheral drive circuit for processing an external input signal and converting the signal into an analog signal are requested to have a high on-current, a low threshold value, a low variation and a steep rising edge. There is no polycrystalline semiconductor thin film for supplying TFTs satisfying these specifications simultaneously. It is therefore necessary to produce polycrystalline semiconductor thin films having different film qualities on one and the same glass substrate.
As a method in which polycrystalline semiconductor thin films having difference film qualities are produced on one and the same glass substrate, there is a method including a first irradiation step in which a silicon material is irradiated with a CW laser and a second irradiation step in which at least a part of the silicon material is irradiated with a pulsed laser beam in an oxygen-containing atmosphere, wherein the film surface is oxidized and formed into a thin film by abrasion in the first and second irradiation steps, as disclosed in Patent Document 1. According to this method, it is supposed that two kinds of polycrystalline semiconductor thin films having different film thicknesses can be produced on one and the same glass substrate. In this method, however, the polycrystalline semiconductor thin film obtained in the first irradiation step is not reformed so that the inhibitors of electric conduction as described above cannot be removed. It is also difficult to control the film thickness by abrasion. In addition, in order to obtain the effect of reduction in leak current according to the aforementioned Patent Document 1, it is more effective to shield an active layer from backlight by use of a light shielding film or the like than to reduce the film thickness of the polycrystalline semiconductor thin film so as to control the effect.

Image display device and method for manufacturing the same


One embodiment of the present invention is a channel loading method, comprising: storing channel parameters; generating a channel loading instruction according to a status of an operation menu and a user instruction; acquiring the channel parameters when the channel loading instruction is obtained, and loading the acquired channel parameters into a television service list database. Another embodiment is a display device having a channel parameter storing module and a channel loading method. A non-transient storage medium is also a part of the present invention.

Field of the Invention
This disclosure relates to the field of display device technologies, and in particular, to a channel loading method, a channel loading apparatus, a display device, a computer program, and a storage medium.
Description of the Prior Art
Before normal use of a display device, television channels need to be searched using an automatic channel search function of the display device. It takes a period of time to search one channel on the display device by means of frequency modulation. Accordingly, much time is consumed in channel searching. This problem is prominent in the factory manufacture test phase of the display device, because in this phase, product test personnel will spend a large amount of time in channel searching, and the time for channel searching is fixed and may not change with the proficiency level of the product test personnel. As a result, the product test personnel spend too much time during the channel test for the display device, and thus the channel test efficiency is low. The display device may be a television or another product device capable of receiving a broadcast signal and having the channel receiving function.

Channel loading method, display device, and non-transient storage medium

BEIJING BOE DISPLAY TECHNOLOGY CO., LTD.


The invention relates to alcohol-free, oral pre-rinse and rinse emulsions containing cleaning and coating compositions that are non-irritating and low foaming thus allowing a residence time sufficient to condition teeth and gums and disruptively affect the plaque matrix. Such disruption allows for the reduction of plaque build-up by either of two efficacious and convenient mechanisms: (1) immediate removal of disrupted plaque matrix by normal brushing or (2) interruption of plaque forming activity in the mouth by frequently cleaning out plaque and plaque precursors, coupled with reduced attachment of plaque by altering the tooth surfaces with the coating compositions.

Dental plaque is present to some degree, in the form of a film; i.e., pellicle, on virtually all dental surfaces. It is a by-product of microbial growth, and comprises a dense microbial layer consisting of a mass of microorganisms embedded in a polysaccharide matrix. The microorganisms present in plaque are mainly coccoidal organisms, particularly in early, soft plaque, which, in the mouths of some persons at least, change to filamentous organisms after a few days. Plaque itself adheres firmly to dental surfaces and is removed only with difficulty even through a rigorous brushing regimen. Moreover, plaque rapidly reforms on the tooth surface after it is removed.
A wide variety of microorganisms are found in the oral cavity, and among these are gram-positive anaerobic rods associated with the development of plaque such as Corynebacterium. Nocardia and Neisseria streptococci, such as S. mutans. S. bovis, S. salivarius. Gram-positive streptococci of the genus Peotostreotococcus have also been identified (see, Robert J. Fitzgerald in The Alabama Journal of Medical Sciences. Vol. 5, No. 3, Jul., 1968, pp. 241-242).
The above mentioned microorganisms play a key role in the etiology of plaque. The bacterial organisms associated with plaque formation produce a capsular material which apparently causes the cells of the organism to adhere to each other, holding the plaque together and allowing for further growth. For example, one of the capsule forming bacteria which occurs in large numbers in early plaque is Neisseria sicca. In addition to the aforementioned microorganisms, there is also present in plaque relatively small amounts of other substances such as salivary proteins, carbohydrates, epithelial cells and leukocytes.
Plaque may form on any parts of the tooth surface, and is found particularly at the gingival margin, in cracks in the enamel, and on the surface of the dental calculus. As discussed in greater detail below, the danger associated with the formation of plaque on the teeth lies in the tendency of plaque to build up and eventually produce gingivitis, periodontitis and other types of periodontal disease, as well as dental caries and dental calculus.
More specifically, dental plaque is a precursor to the formation of the hard crystalline buildup on teeth referred to as dental calculus. Both the bacterial and the nonbacterial components of plaque mineralize to form calculus, which comprises mineralized bacteria as well as organic constituents, such as epithelial cells, live bacteria, salivary proteins, leukocytes, and crystals of substances having molecularly bound calcium and phosphorus, e.g., hydroxyapatite, 3Ca.sub.3 (PO.sub.4).sub.2 .multidot.Ca(OH).sub.2, octacalcium phosphate, Ca.sub.8 (HPO.sub.4).sub.2 (PO.sub.4).sub.4 .multidot.5H.sub.2 O, brushite, CaHPO.sub.4 .multidot.2H.sub.2 O, and whitlockite, which is considered to have the form of a beta-Ca.sub.3 (PO.sub.4).sub.2.
Dental plaque and, hence, calculus are particularly prone to form at the gingival margin, i.e., the junction of tho tooth and gingiva. The buildup of plaque at the qingival margin is believed to be the prime cause of gingivitis and other periodontal disorders.
Regular tooth brushing with a conventional dentifrice for some persons greatly retards or even prevents the accumulation of significant amounts of plaque and calculus. For other persons, however, plaque builds up rapidly even with regular brushing which, in turn. leads to the formation of calculus, caries, and presents the danger of periodontal diseases. Removal of plaque and/or calculus by a dentist is currently the only safeguard against serious gingival inflammation caused by the accumulation of significant amounts of plaque in some individuals. It is widely recognized in dentistry that a rigorous brushing regimen alone for many individuals will not prevent the formation of significant amounts of plaque.
Mouthwashes are employed in conventional regimens of oral hygiene. However, conventional mouthwashes serve primarily to sweeten the breath, are formulated for that purpose, and are believed not to function in any significant way to loosen or remove plaque from the dental surfaces. Moreover, since the user typically does not employ a mouthwash expressly for the purpose of cleansing the teeth of plaque, mouthwashes are not routinely used immediately prior to brushing as a way of rendering plaque and/or calculus more amenable to removal during the subsequent brushing process.
Most mouthwashes and pre-rinses contain alcohol and other antimicrobial substances which may alter the critically balanced microflora of the mouth. Generally, these alcohol containing preparations cannot be used on sensitive or irritated gums nor safely by children or those individuals recovering from alcohol abuse. Moreover, the alcohol content in these preparations usually restricts the practical requirement of sufficient contact time in the mouth due to the irritation of the oral mucosa. Most rinse and pre-rinse preparations include instructions advising the consumer to swish the product in the mouth for about 60 seconds. The pain and mucosa irritation due primarily to alcohol astringency is often so intense that most rinse and pre-rinse users actually expectorate in only a few seconds which is usually followed by a water rinse. This relatively short residence time followed by water rinsing dramatically reduces any mouth cleansing and/or plaque fighting effect that these preparations might have.
Most oral rinses sold commercially today contain alcohol in concentrations ranging from between about 5 and about 27% by weight. These high alcohol concentrations impart microbial stability to these rinses. These antiseptic rinses also usually contain other antimicrobial substances such as phenolics, thymol, eucalyptol, cetylpyridinium chloride, sodium benzoate, sanguanarine root, etc., at levels far beyond that required for preservation during storage. The cleaner concentrations generally range from 0.1 to about 0.25%, and generally less than 1.0%. Most rinses make various claims ranging from germ kill, cavity fighting and plaque or tartar control to breath freshening, but few address the critical issue; cleaning the oral cavity.
Various types of commercial oral rinses are employed in diverse regimens of oral hygiene. These include:
a. Conventional mouthwashes which serve primarily to sweeten the breath with volatile flavor odors and are not formulated to function in any significant way to cleanse the mouth of debris and/or to loosen or remove plaque from dental surfaces. PA1 b. Pre-rinse formulations, used immediately prior to brushing as a way of rendering plaque and/or calculus more amenable to removal during the subsequent brushing process. See for example, U.S. Pat. No. 4,657,758, and PA1 c. Gingivitis and/or tartar control rinses containing antimicrobials such as phenols, sanguinaria, chlorhexidine and stannous fluoride; and antitartar or plaque fighters such as sodium or potassium pyrophosphates and sodium benzoate. Some of these are described in the review by K. S. Kornman, Dent. Placue Control Meas. Oral Hyg. Pract. Proc., pp. 121-142 (1986). PA1 a. interfere with the continued swishing action required i.e., up to 60 seconds, PA1 b. does not fill the mouth to an unpleasant level, and PA1 c. does not interfere with effective liquid contact with tooth and mouth surfaces. PA1 a. condition gums and teeth, PA1 b. coat surfaces of the mouth with a lasting, plaque disrupting coating and cleaning mixtures that is ingestible, PA1 c. clear the mouth of debris, PA1 d. impart a lasting smooth, clean, just-brushed feeling to the mouth, PA1 e. are low-foaming and ingestible, PA1 f. disrupt the plaque matrix and control plaque formation without killing germs and/or altering the microflora of the mouth, PA1 g. are particularly effective in conditioning sensitive and irritated gums, and PA1 h. can be safely used as children's rinses; not only because they are alcohol free but also because the cleaner/coating compositions of the invention can be ingested and thus are not harmful if accidentally swallowed by a child.
All of these commercial rinses are characterized by a relatively high alcohol content and antimicrobial and/or antiseptic activity that disrupts the critically balanced microflora of the mouth. This alcohol content also provides the rinse a microbially stable formulation, which does not support the growth of microorganisms, and allows the rinse to be stored for prolonged periods and/or used without concern for microbial contamination. The alcohol also serves to reduce the foamability of the rinse. However, this foaming control is limited to relatively low surfactant concentrations in the rinse. Finally, alcohol also functions as a solvent for the flavor oils typically included in commercial rinses.
There are inherent limitations in the use of alcohol containing oral rinses. For example, most adults will experience some form of gum irritation, on average about once a year. This irritation ranges from sites of early gingivitis, canker sores and trench mouth to periodontal disease. At such times, alcohol rinses cause even greater pain and are often replaced by rinsing with water.
Alcohol containing rinses and/or pre-rinses are generally not used by children. Most parents are concerned about the alcohol content, while many children reject the alcohol bite and astringency characteristic of such products. Indeed, most alcohol containing rinses and/or pre-rinses boldly display the language "Keep Away From Children" on their labels. Similarly large numbers of adults reject alcohol based rinses for various personal reasons. Additionally, recovering alcoholics avoid alcohol rinses because of the threat that these substances can trigger a negative response. For example, most institutionalized personnel are not allowed to use alcohol based rinses.
There is, therefore, a definite need in the art for an oral hygiene composition which is microbially stable, alcohol-free and non-irritating; that can be used as an oral rinse or pre-rinse to clean and condition the teeth and gums, cleanse the mouth of debris and disrupt plaque matrix formation, without substantially altering the microflora balance of the oral cavity.
In view of the foregoing, it is an object of this invention to provide an improved dental rinse which is non-irritating and which has a disruptive cleaning effect upon plaque; which conditions the teeth and gums and which clears the mouth of debris, and disrupts plaque matrix formation, all without altering the balanced microflora of the oral cavity; wherein the rinse is alcohol-free yet microbiologically stable.
It is also an object of this invention to provide an improved method of oral hygiene, i.e., the method of disrupting plaque, clearing the mouth of debris, conditioning teeth and gums without altering the microflora balances of the oral cavity, which entails using the alcohol-free rinse of the present invention.
It is a further object of this invention to provide an improved process for manufacturing an alcohol-free dental rinse.

Alcohol-free, oral rinse and pre-rinse emulsions method of prepration and method of use


The invention provides methods and compositions for identifying modulators, particularly peptide modulators, of cell surface receptor activity. Specifically, the invention provides a cell containing a recombinant nucleic acid encoding a polypeptide modified for intracellular presentation, which cell may further comprise one or both of a recombinant nucleic acid encoding a binding partner for that polypeptide and recombinant nucleic acid encoding a test polypeptide. The subject cell may be a member of a library of cells, and the library may be used in screening methods for identifying test polypeptides (e.g., conformationally restrained polypeptides) having cell surface receptor modulatory activity. The invention finds use in a variety of drug-discovery applications.

Extracellular signaling molecules are typically hydrophilic and do not generally cross the hydrophobic plasma membrane of a cell by simple diffusion. Accordingly, extracellular signaling molecules are usually specifically bound by receptors that are situated on the surface of a target cell (i.e., "cell surface receptors"), and binding of a signaling molecule to a cell surface receptor modulates activity of the receptor to initiate a signal in the target cell.
Cell surface receptors play a pivotal role in almost every aspect of cell biology. Because of this role, as well as their accessibility to hydrophilic molecules, cell surface receptors have become an attractive target for drug discovery. Because peptides are relatively small, hydrophilic (making them easily formulated for administration), and can be made in large quantities either synthetically or recombinantly, peptide modulators are in particularly great demand.
Non-naturally occurring modulators of a particular cell surface receptor are typically identified from a large library of candidate agents (a library having, e.g., 106-109 different compounds). Each member of such a library is typically assayed for receptor modulatory activity, and receptor modulators are identified using the assay. Assuming the sensitivity of the assay is not limiting, the success of such screening assays primarily depends on the size of the library of candidate agents screened: the larger the library used, the more modulatory agents will be identified. Accordingly, in view of the great demand for peptide modulators of cell surface receptor activity, there is a also great demand for methods of screening large peptide libraries to identify those peptides.
However, libraries containing large numbers (e.g., 107-1012) of candidate peptides are generally prohibitively expensive to make, and, as such, are generally not available. For example, assuming that a single peptide can be synthesized in an amount suitable for assaying for the cost of $10, a library of 107 peptides would cost $100M. As such, while there is a great need for methods of identifying peptide modulators of cell surface receptor activity, this need is generally unmet because large libraries of candidate peptides are not generally available.
Accordingly, a great need still exist for methods of identifying peptide modulators of cell surface receptor activity. The invention described herein meets this need, and others.

Methods and compositions for identifying peptide modulators of cell surface receptors


Methods for dispersing and binding ceramic materials in aqueous media are disclosed. The methods utilize water-soluble polymers having pendant derivatized amide, ester or ether functionalities for dispersing and binding various classes of ceramic materials.

Ceramic materials are commonly prepared by mixing powdered ceramic oxides such as magnesia, alumina, titania and zirconia, in a slurry along with additives, such as dispersants and binders. The slurry may be spray dried to produce ceramic particles. The particles are pressed into an aggregate structure, called a "green ceramic," having a desired shape and subsequently subjected to a severe heat treatment known as sintering. The sintering process converts the green ceramic into a cohesive "fired ceramic", having a nearly monolithic polycrystalline ceramic phase.
The binder serves to hold the ceramic particles of the green ceramic in the desired shape after pressing. The binder can also provide lubrication while the particles are pressed. Preferably, the binder combusts or vaporizes completely during the sintering process leaving no trace of the binder in the fired ceramic. In performing these functions, binders significantly affect the properties of the fired ceramics which are ultimately produced.
In commercial practice, poly(vinyl alcohols) are widely used as ceramic binders. Additionally, poly(ethylene oxide) and ethylene-vinyl acetate copolymers reportedly have been used as binders for particulate material, such as granular silica gel.
For example, polymeric binders containing substantially hydrolyzed copolymers made from monomers having ester or amide functional groups, poly(vinylformamide) or a copolymer of vinyl alcohol and vinyl amine are disclosed in U.S. Pat. Nos. 5,358,911; 5,487,855 and 5,525,665.
Furthermore, polymeric treatments have been disclosed in U.S. Pat. Nos. 4,680,339; 4,731,419; 4,885,345 and 5,084,520. Utility for the treatments has been disclosed to be as dispersants in water treatment, scale inhibitors in industrial and natural waters, flocculants, coagulants and thickeners; but ceramics applications of binding and dispersancy have not been disclosed.
Although commercially available binders are satisfactory for many applications, a need exists for improved binders which provide still greater strength and/or increased density in green ceramic materials. Greater green strength reduces breakage during handling of the green ceramics and, generally, is associated with higher quality fired ceramics. Preferably, the improved binders would be cheaper and more versatile than previously known binders.
Spray drying is an evaporative process in which liquid is removed from a slurry containing a liquid and a substantially non-volatile solid. The liquid is vaporized by direct contact with a drying medium, usually air, in an extremely short retention time, on the order of about 3 to about 30 seconds. The primary controlling factors in a spray drying process are particle size, particle size distribution, particle shape, slurry density, slurry viscosity, temperature, residence time, and product moisture.
The viscosity of the slurry must be suitable for handling and spray-drying. Although spray-drying equipment conditions may be adjusted to handle a variety of viscosities, larger particles will usually result from higher viscosity slurries.
Those of ordinary skill in the art are familiar with the spray-drying process used in the production of ceramic materials, and will be able to optimize the control factors of spray-drying to best advantage. Alternatively, the spray drying process may be replaced by other well known drying methods, such as granulation, tape casting and slip casting.
Spray drying of the slurry produces substantially dry, free-flowing powder particles which contain the ceramic, the binder and the optional materials described above. The dry particles are granules which are generally spheroidal in shape and have an effective diameter of about 50 to about 300 micrometers. Typically, about 0.5 percent to about 8 percent of the binder, based on the dry weight of the ceramic powder, is present in the dry particles.
In granulation, a mixture of dry powder or powders is mixed or rolled, commonly in a barrel shaped apparatus. Water and/or a binder solution is sprayed into the mixing powder causing aggregation of the small particles into larger granules. The size of the granules is controlled by the amount of material sprayed into the powders and the speed with which it is sprayed. Granulated powders may be screened to a desired size and pressed to shape in a pressing operation prior to sintering. Alternatively, the granules themselves may be the desired product and may be sintered directly.
Tape casting is commonly used to produce thin substrates for the computer industry. In the process, a thick ceramic slurry containing ceramic powder, dispersant and binders is prepared. This slurry is cast onto a smooth surface such as a Mylar or plastic sheet and the thickness is controlled by passing the sheet under a blade which smoothes the slurry surface and scrapes off excess material. The slurry tape is dried to a plastic state and cut and shaped to specification. The amount of binders present in tape casting is very high, typically on the order of 15 to 20 wt. % of the ceramic powder mass.
In fluidized bed spray drying, small "seed" particles are placed in a column and hot air is blown into the seed powder from below suspending the particles in the column. A ceramic slurry is sprayed onto the seed particles from above, causing them to grow. When the particles reach a large enough size, they are siphoned out of the dryer while more seed particles are introduced. This process can produce powder for further forming processes, or the powder itself may represent the desired product, in which case it would be sintered to produce the final ceramic.
The dry particles are compacted to produce an aggregate, green ceramic structure. Preferably, the particles are compacted by pressing in dies having an internal volume which approximates the shape desired for the final fired ceramic product. Alternatively, the particles are compacted by roll compacting or other well-known compacting methods. The spray dried blend of powder, binder, and optional surfactants and lubricants is relatively free flowing so that it can enter and closely conform to the shape of the pressing dies.
Inside the dies, the dry particles are subjected to a pressure which is typically in the range of about 5000 to about 50,000 psi. Pressing the particles produces an aggregate structure, called a green ceramic, which retains its shape after removal from the die.
One forming technique used for spray dried or granulated material is roll compaction, also referred to as roll pressing. This technique takes a dry powder and crushes it between two rollers in a continuous process. This process produces sheets of ceramic of various widths and thicknesses. These sheets can be cut to shape and sintered to produce the final ceramic body. The process is commonly used to produce ceramic substrates for the electronics industry.
Dry pressing involves filling a shaped die with spray dried or granulated powder and pressing it at high pressures. The pressing occurs through movable pistons at the top and/or bottom of the die cavity. The process can be used to produce fairly complex geometries in a single forming step. The ceramic body that results is ejected from the die and sintered to produce a final ceramic product.
Isostatic pressing is similar to dry pressing in that a ceramic powder is pressed in a die cavity. In isostatic pressing, however, all or part of the die wall consists of a flexible material. After filling the die cavity with powder, the die is submerged in a liquid pressure chamber and pressure is applied to squeeze the die and compact the powder. Unlike dry pressing, no movable parts are involved. Isostatic pressing is commonly used on large or very long parts to minimize cracking or lamination of the final ceramic green body.
Extrusion involves the pushing of a concentrated, plastic, slurry through an orifice. The orifice is of the size and shape of the desired ceramic body. This process is commonly used to produce ceramic tubes or similarly shaped pieces. The slurry used is prepared from dry powders which are mixed with water, organic binders and lubricants, and a coagulant. This slurry is usually predried in a filter press or similar apparatus to remove excess water and thicken the slurry to a plastic material. The material is then extruded through a press which is either piston or screw driven. The extruded material is cut to length, dried, and sintered.
Jiggering is commonly used in the whiteware industry to shape an extruded or filter pressed ceramic slurry. Typically, a portion of the plastic slurry is placed on a rotating wheel and shaped by rollers and/or knife blades to a desired geometry. This body is then dried and sintered.
Another ceramic forming method, that is used for parts of complex shape, is slip casting. In slip casting, a concentrated ceramic slurry (slip) is poured into a mold with an internal shape of the desired ceramic body. The slurry used must be highly concentrated to prevent settling of particles and/or excessive shrinkage during drying. At the same time, the slip must be fluid enough to completely fill the mold and allow escape of air bubbles. The presence of a polymeric binder adds strength to the cast body preventing breakage during mold removal and handling of the body prior to sintering.
Heating the aggregate structure drives off volatile materials such as water, and bums off organic materials, such as binders or surfactants. When a sufficiently high temperature is reached, the particles of the aggregate structure begin to fuse, but do not fuse completely, and become fastened to one another to reproduce a relatively strong fired ceramic material having essentially the desired shape.
The slurry is, for example, spray dried to produce substantially dry particles. The particles are preferably pressed to produce an aggregate, green ceramic structure and heated to produce a fired ceramic material. Alternatively, the particles can be formed into an aggregate, green ceramic structure by roll compaction or other well-known methods.
Although commercially available binders are satisfactory for many applications, a need exists for improved binders which provide still greater strength and/or high density in green ceramic materials. Greater green strength reduces breakage during handling of the green ceramics and, generally, is associated with higher quality fired ceramics. Preferably, the improved binders would be cheaper and more versatile than previously known binders.
The present invention also relates to a method for dispersing ceramic materials. In particular, the present invention relates to a method for dispersing one or more ceramic materials in an aqueous medium by using a polymeric dispersant formed from acid-containing monomers and hydroxy functional monomers.
Ceramic materials are often used to prepare lightweight, strong, thermally and chemically resistant products. Because of difficulties associated with the handling of solid ceramic materials, it is desirable for the ceramic materials to be in the form of an aqueous dispersion. Aqueous dispersions of ceramic materials are, however, often unstable, exhibiting sediment formation upon standing. Upon standing, the dispersion agglomerates and becomes non-homogeneous, and creates difficulty in handling. These agglomerates may also damage pipes, pumps, and other dispersion handling mechanical equipment. The use of dispersants overcomes these difficulties, and also improves strength and density of formed ceramic parts, particularly those made by dry press, slip casting, and tape casting processes.
Polymers are known for use as dispersants for ceramic materials. Typical polymeric dispersants for ceramic materials include polymers formed from acid-containing monomers such as, for example, poly(acrylic acid) and poly(methacrylic acid). For example, anionic polymers produced by hydrolyzing a terpolymer of maleic anhydride, N-vinylpyrrolidinone and a vinyl compound selected from the group consisting of acrylic acid, acrylamide, methyl methacrylate and butyl vinyl ether is disclosed in U.S. Pat. No. 5,266,243. Additionally, polymeric dispersants consisting of from 5 to 95 percent by weight of one or more hydroxy functional monomers and from 95% to 5% by weight of one or more acid-containing monomers are disclosed in U.S. Pat. Nos. 5,567,353 and 5,532,307. The hydroxy functional monomer is selected from the group consisting of hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, allyl alcohol, allyloxyethanol, allyl propoxylate, vinyl acetate, 1-butene-3,4-diol and 3-allyloxy-1,2-propane diol.
Furthermore, imidized acrylic polymers have been disclosed for the increase of flowability in cement compositions in U.S. Pat. No. 5,393,343.
While such polymers perform adequately in dispersing some ceramic materials, certain ceramic materials are more difficult to disperse, and conventional polymeric dispersants are not adequate. Ceramic materials which present particular difficulty in forming dispersions include nitrides such as, for example, boron nitride. U.S. Pat. No. 5,209,885 describes dispersing silicon nitride for extrusion by the use of a graft copolymer comprising a polyoxyalkylene backbone with polyacrylate side chains.
The present invention seeks to provide a method for dispersing ceramic material, including several ceramic materials known to be difficult to disperse.

Preparation and utility of water-soluble polymers having pendant derivatized amide, ester or ether functionalities as ceramics dispersants and binders