Interconnect driver circuits that can be used in the interconnect structures of dynamic integrated circuits (ICs) such as dynamic programmable logic devices (PLDs). An exemplary IC includes two or more logic circuits, and two or more self-resetting interconnect driver circuits coupled between the logic circuits. Each self-resetting interconnect driver circuit includes a multiplexer circuit driving a buffer circuit. In a first state, the buffer circuit drives a first value onto the output terminal of the buffer circuit. In a second state, the buffer circuit first drives a second value onto the output terminal of the buffer circuit and then returns to the first state. Several different circuits are described in detail.

Programmable logic devices (PLDs) are a well-known type of integrated circuit that can be programmed to perform specified logic functions. One type of PLD, the field programmable gate array (FPGA), typically includes an array of programmable tiles. These programmable tiles can include, for example, input/output blocks (IOBs), configurable logic blocks (CLBs), dedicated random access memory blocks (BRAM), multipliers, digital signal processing blocks (DSPs), processors, clock managers, delay lock loops (DLLs), and so forth.
Each programmable tile typically includes both programmable interconnect and programmable logic. The programmable interconnect typically includes a large number of interconnect lines of varying lengths interconnected by programmable interconnect points (PIPs). The programmable logic implements the logic of a user design using programmable elements that can include, for example, function generators, registers, arithmetic logic, and so forth.
The programmable interconnect and programmable logic are typically programmed by loading a stream of configuration data into internal configuration memory cells that define how the programmable elements are configured. The configuration data can be read from memory (e.g., from an external PROM) or written into the FPGA by an external device. The collective states of the individual memory cells then determine the function of the FPGA.
Another type of PLD is the Complex Programmable Logic Device, or CPLD. A CPLD includes two or more "function blocks" connected together and to input/output (I/O) resources by an interconnect switch matrix. Each function block of the CPLD includes a two-level AND/OR structure similar to those used in Programmable Logic Arrays (PLAs) and Programmable Array Logic (PAL) devices. In CPLDs, configuration data is typically stored on-chip in non-volatile memory. In some CPLDs, configuration data is stored on-chip in non-volatile memory, then downloaded to volatile memory as part of an initial configuration sequence.
For all of these programmable logic devices (PLDs), the functionality of the device is controlled by data bits provided to the device for that purpose. The data bits can be stored in volatile memory (e.g., static memory cells, as in FPGAs and some CPLDs), in non-volatile memory (e.g., FLASH memory, as in some CPLDs), or in any other type of memory cell.
Other PLDs are programmed by applying a processing layer, such as a metal layer, that programmably interconnects the various elements on the device. These PLDs are known as mask programmable devices. PLDs can also be implemented in other ways, e.g., using fuse or antifuse technology. The terms "PLD" and "programmable logic device" include but are not limited to these exemplary devices, as well as encompassing devices that are only partially programmable.
A PLD interconnect structure can be complex and highly flexible. For example, Young et al. describe the interconnect structure of an exemplary FPGA in U.S. Pat. No. 5,914,616, issued Jun. 22, 1999 and entitled "FPGA Repeatable Interconnect Structure with Hierarchical Interconnect Lines", which is incorporated herein by reference in its entirety.
Programmable interconnect points (PIPs) are often coupled into groups that implement multiplexer circuits selecting one of several interconnect lines to provide a signal to a destination interconnect line or logic block. A routing multiplexer can be implemented, for example, as shown in FIG. 1. The illustrated circuit selects one of several different input signals and passes the selected signal to an output terminal. Note that FIG. 1 illustrates a routing multiplexer with eight inputs, but PLD routing multiplexers typically have many more inputs, e.g., 28, 30, or 32. However, FIG. 1 illustrates a smaller circuit, for clarity.
The routing multiplexer of FIG. 1 includes eight input terminals IN0-IN7 and ten pass gates 100-109. Pass gates 100-103 selectively pass input signals IN0-IN3, respectively, to a first internal node INT1. (Note that In the present specification, the same reference characters are used to refer to terminals, nodes, signal lines, and their corresponding signals.) Each pass gate 100-103 has a gate terminal driven by a configuration memory cell M12-M15, respectively. Similarly, pass gates 104-107 selectively pass input signals IN4-1N7, respectively, to a second internal node INT2. Each pass gate 104-107 has a gate terminal driven by one of the same configuration memory cells M12-M15, respectively. From internal nodes INT1, INT2, pass gates 108, 109 are controlled by configuration memory cells M10, M11, respectively, to selectively pass at most one signal to a third internal node INT3.
The signal on internal node INT3 is buffered by buffer BUF to provide output signal ROUT. Buffer BUF includes two inverters 111, 112 coupled in series, and a pullup (e.g., a P-channel transistor 113 to power high VDD) on internal node INT3 and driven by the node between the two inverters.
Values stored in configuration memory cells M10-M15 select at most one of the input signals IN0-IN7 to be passed to internal node INT3, and hence to output node ROUT. If none of the input signals is selected, output signal ROUT is held at its initial high value by pullup 113. Pullup 113 also pulls signal INT3 fully to power high VDD to fully shut off the pullup of inverter 111.
Clearly, a circuit implemented in flexible programmable logic can potentially be slower than circuitry implemented using dedicated logic (i.e., logic designed for a specific purpose). For example, a circuit implemented using programmable lookup tables (LUTs) and flip-flops might need to traverse a succession of LUTs and interconnections between each pair of successive flip-flops, as shown in FIG. 2. The exemplary signal path illustrated in FIG. 2 connects an output terminal of flip-flop 201 with an input terminal of flip-flop 209, and sequentially traverses interconnect 202, LUT 203, interconnect 204, LUT 205, interconnect 206, interconnect 207, and LUT 208. The path delay includes one clock-to-out delay for flip-flop 201, four interconnect delays, three LUT delays, and one setup time for flip-flop 209. The total of these delays determines the minimum clock period for the illustrated signal path.
In non-programmable circuits, one known method of increasing circuit performance is the use of dynamic logic. In dynamic circuitry, many or all nodes (e.g., all output nodes) are pre-charged to a first known value. This state is referred to herein as the "pre-charge state". At a later time the circuit enters the "evaluation state", in which the pre-charge is released and some of the pre-charged nodes change to a second known value, as determined by the logic. In clocked dynamic logic, for example, all nodes can be pulled high at a falling edge of a clock, and then some of the nodes are selectively pulled low at the rising edge of the clock. Therefore, whenever the clock is low the circuit is in the pre-charge state, and whenever the clock is high the circuit is in the evaluation state. (Clearly, dynamic circuits also can be designed to operate in the opposite fashion, i.e., to be in the pre-charge state whenever the clock is high, and in the evaluation state whenever the clock is low.) Thus, only the falling edge on the pre-charged nodes is speed-critical, and circuitry can be skewed for a fast falling edge and a slow rising edge on these nodes.
One of the drawbacks of clocked dynamic logic is that distributing the heavily loaded clock signal throughout the dynamic logic consumes a lot of power. Another type of known dynamic logic avoids using a clock signal by utilizing a self-resetting technique, in which the output node is pre-charged during the pre-charge state, then is conditionally discharged (evaluated) whenever an input node of the circuit changes state. Thus, a low pulse might or might not appear at the output node, based on the values of the various input signals.
As is clear from the example illustrated in FIG. 2, interconnect delays can constitute a significant portion of the delay on a critical path in a PLD design. Therefore, it is desirable to provides circuits that facilitate the reduction of interconnect delays in a PLD. It is further desirable to provide circuits that facilitate the reduction of interconnect delays in other types of integrated circuits (ICs), including non-programmable ICs.

Interconnect driver circuits for dynamic logic


An individually controlled needle tufting machine has a reciprocable latch bar for latching and unlatching selective needle holders, each needle holder being guided between a pair of guide plates and carrying a respective needle so that each needle selectively may be driven by the latch bar. The guide plates each include a plurality of curvilinear ridges and the edges of the needle holder are curvilinear and are received within a respective spaced apart pair of ridges within which they are guided as the needle holder reciprocates. The plates include vertically spaced apart inserts within which the ridges are formed. The needle holder has a yarn clamp mounted internally adjacent the bottom and a leaf spring has a leg mounted externally of the holder and has a leg entering internally to act upon and urge the yarn clamp.

This invention relates to tufting machines and more particularly to a tufting machine wherein the needles are carried by needle holders which are selectively latched to a reciprocating latch bar, the needle holders being mounted between guide plates adjustably mounted in the machine.
Tufting machines which produce carpet, basically include a large frame having a head within which a rotatable mainshaft is mounted and from which needle driving structure is supported for reciprocating a multiplicity of needles. The frame also includes a bed within which oscillating loopers or hooks are mounted for cooperating with the needles to form loops of yarn, knives being used in conjunction with the hooks to cut the loops in many tufting machines. As the tufting art has developed, there have been a substantial number of innovations to obtain unique patterning effects. One such innovation has been to shift the needles laterally in accordance with a pattern. Another innovation has been to provide each needle with a sew/no-sew capability by mounting the needles on individual needle holders which are reciprocated selectively by either being latched to or disengaged from a reciprocating latch bar, the latter being reciprocably driven continuously from mechanism driven by the rotating mainshaft. When latched to the latch bar, the needle reciprocates into cooperation with the hook to form a loop. The latching occurs by means of latch pins on pneumatic cylinders driven in accordance with a pattern. Machines of this type are known as controlled needle machines, and when each needle is individually controlled in this manner, it is known as an individual controlled needle machine.
A recent development in the tufting art is to combine the individual control needle machine concept with the shifting needle concept, and to feed the backing material intermittently. This provides a tufting machine wherein the needles may be threaded with a number of different yarns, e.g., yarns of different colors, and a needle having a yarn of a particular color may be inserted into the backing at any of a selected number of locations so that extremely precise multi-color patterns may be produced similar to the fine woven carpets produced by looms. A machine of this type is illustrated in Bardsley U. S. Pat. No. 5,653,184.
In such tufting machines, as illustrated in the aforesaid patent, the needles are individually mounted in an elongated holder, one end of which is adapted for latching to the latch bar and the other end of which mounts the needle. The needle holder is normally biased by a return spring into a non-sewing position and is driven into a sewing position during sewing against the bias of the spring by the needle drive arrangement. The needle holder includes a spring biased ratchet-like clamp arrangement which causes the yarn to be drawn from the supply when the needle holder moves from the non-sewing position to the sewing position by trapping the yarn between the clamp and a wall of the holder. When the needle holder moves back to the non-sewing position, the tension on the yarn urges the clamp away from the wall of the holder so that the yarn can pass through the clamp.
A problem that has arisen with this construction of the prior art is that the ratchet-type clamp of the needle holder is in a position whereby access to the spring for removal or replacement is difficult. In a majority of cases if these parts fail or need replacement, it has been necessary immediately to replace the entire needle holder, thereby increasing cost of replacement parts and machine down-time. The spring in the prior art is within the body of the needle holder or within an extension secured to the needle holder, the extension having a deep slot milled between two thin wall portions. Pins within the slot must be positioned so as to guide yarn and hold the ratchet-type mechanism and spring within the slot. A coil spring having two legs one of which is disposed about the pin on which the clamp is journalled and the other of which is disposed about another pin so as to bias the clamp against the yarn is disposed within the slot. The slot within the needle holder is milled so as to leave a little material at the end to permit a hole to be formed for mounting the pin about which the spring is curled.
Moreover, the needle holder on such machine is mounted for movement by means of a pair of ridged guide blocks or plates having parallel channels therein. The guide bars or plates are secured to a top and bottom surface of a needle support bar and the ridges or channels in the guide plates define therebetween positions in which respective needle holders can be mounted. A corresponding ridged pair of fixing plates are secured to a top and bottom surface of a fixing bar and can be secured in a position relative to the guide plates so that the needle holders are secured in position in a tufting machine intermediate respective ridges formed in the guide plates and fixing plates. Each of the fixing and guide plates is adjustable relative to the needle support bar and/or fixing bar in order to allow the needle holder to be adjusted to ensure accurate alignment with the drive mechanism. The drive plates and fixing plates may be modular in so far as they have a width such that each plate retains only a small number of needle holders in position in the machine.
The arrangement of the mounting blocks in the prior art is such that the needle holders cannot be removed readily from the tufting machine in a direction transverse to the direction of reciprocation, and thus in order to remove the needle holder it is presently required to penetrate the backing material, cut an opening and remove the needle holder in the vertical or reciprocation direction.
A problem arises with this existing mounting system since the correct alignment of the needle holder and the drive mechanism are dependent upon the relative positioning of at least four plates, thereby making it difficult and time consuming to achieve such correct alignment.
Additionally, thermal expansion may cause the guide plates and/or the needle holder to vary in shape or dimension. If the needle holder has a straight or dovetail cross sectional configuration as in the prior art, such expansion may result in the needle holder becoming misaligned by twisting or rotating slightly in the guide. The thermal expansion resulting in such variation may be caused by frictional heating of the guide plate and/or the fixing plate during operation.


A hybrid grounding connector is provided which combines the positive attributes of currently used connections. A recess is pre-milled, formed or extruded into the body of a compression connector and the recess is pre-filled with solder. After conductors are installed in the connector, an external heat source is applied to heat the solder until it flows into strands of the conductors and forms a solidified joint of the compression connector.

There are three common methods of providing a grounding connection for a plurality of conductors. These methods include exothermic connectors, mechanical connectors and compression connectors. Each method has its own advantages and disadvantages. Exothermic connectors are believed to be the superior connection among the three mentioned methods, as it yields a solid conductor mass if the method is carried out properly. The solid joint that is produced is not susceptible to mechanical or electrical degradation. However, some disadvantages of this method include the types of tools required and the susceptibility of this method to environmental conditions such as rain or humidity. Mechanical connectors are easy to install and require no special tools for installation of conductors. However, mechanical connectors are often not preferred as a grounding method, as a tightened mechanical connector can become loose through vibrations over time which does not provide a permanent connection. Compression connectors are considered to form a permanent connection, but are believed in some instances to be inferior to exothermic connections due to small voids which can exist in the compressed joint which may allow moisture to penetrate the joint, leading to oxidation or degradation of the connection over time. Compression connectors are considered to be inferior to exothermic for resistance to fault currents. An improved connector which combines the positive attributes of the previously described methods is desired.


A method for monitoring a select analyte in a sample in an electrochemical system. The method includes applying to the electrochemical system a time-varying potential superimposed on a DC potential to generate a signal; and discerning from the signal a contribution from the select analyte by resolving an estimation equation based on a Faradaic signal component and a nonfaradaic signal component.

The use of electrochemical means of detection has often been chosen for its simplicity, both in terms of device manufacture and in terms of ease of use. The principle mode of selectivity of electrochemistry (both for amperometric and potentiometric modes) is the reduction-oxidation (also called "redox") potential of the analyte (which is the chemical species of electrochemical interest). For example, using the technique of amperometry (where the potential is applied to the electrode, and the resulting current is measured), the selectivity towards the analyte is achieved based on the redox potential of the analyte.
The signal that is generated at the electrode can depend on many factors and properties of the electrochemical system. Examples of properties of the sample that affect the transport of the analyte include viscosity, temperature, density, and ionic strength. The variations that affect the transport of the analyte can subsequently affect the measured electrochemical signal. Examples of such transport mechanisms include diffusion, migration, and convection.
In another example, the properties of the electrode itself can affect the transport of the analytes and/or the kinetics of any reactions that may generate the measured electrochemical signals. Examples of such properties include the effective electrode area, the geometry of the electrodes, the geometry of the sample chamber, the extent of electrode fouling, diffusional bather membranes over the electrode, and catalytic properties of the electrode material.
Electrochemical sensors are commonly found in a number of sensing applications, from medical biosensors to environmental and gas sensors. There are commonly two modes of electrochemical measurement, amperometric and potentiometric. Amperometric sensors operate on the principle of applying a voltage potential to an electrode and measuring the resulting current. Examples of amperometric sensors include most commercial glucose biosensors and many gas sensors. Potentiometric sensors operate on the principle of applying a current to an electrode and measuring the resulting potential. It is often the case that the applied current is kept at zero amps. The pH electrode is an example of a potentiometric sensor.
FIG. 1 shows the action of an amperometric sensor in which a voltage is applied to the electrode 310 which causes a particular analyte (the substance being measured) in the sample to be oxidized (i.e., giving up electrons to the electrode). The oxidation causes a current 315 to be generated which can then be detected and analyzed. The potential at which the analyte oxidizes is called the "oxidation potential" of the analyte.
Generally speaking, the term "redox potential" is used to indicate the potential at which an analyte is either oxidized or reduced. In the sensor of FIG. 1, ferrocyanide ("FERRO") 300 transfers electrons to the electrode if the potential is high enough to cause the electrochemical reaction to occur. Once the electrons are transferred, ferrocyanide is oxidized to ferricyanide ("FERRI") 305.
Thus, in FIG. 1, a sufficiently high potential is being applied to oxidize ferrocyanide, the reduced form of the electroactive species, to the oxidized form, ferricyanide, and the resultant current 315 detected by the electrode depends on the concentration of the reduced species.
As discussed above, the current from amperometric sensors depends on a number of factors in addition to the concentration of the analyte of interest. Traditional amperometric methods rely on the assumption that only the concentration of the analyte changes from measurement to measurement; hence, when other factors of the electrochemical system vary, the measured signal and the estimate of the analyte concentration can be incorrect. Potentiometric sensors also suffer from related factors, including transport of the analyte and electrode fouling. Variations in these factors would add uncertainty and error to the measured signal. For example, FIG. 2 shows the DC current from two amperometric sensors where the effective electrode area is changed. Data points 455 are measured in a sample containing 10 mM ferrocyanide. Data points 450 are measured in a sample containing 20 mM ferrocyanide. In both cases, as the electrode area varies, the measured DC current signal varies as well. Furthermore, for a given electrode area, increasing the analyte concentration from 10 mM to 20 mM results in measuring an increased current signal. This illustrates the dependence of the measured DC current signal on the electrode area and on the analyte concentration.
Several factors may contribute to a sensor having variable electrode area. One source may be errors during manufacturing that may lead to variability in the electrode area from sensor to sensor. Another factor may be deterioration of the electrode during use. Another factor may be incomplete contact of the sample with the sensor electrode, examples of which are illustrated in FIGS. 8 and 9.
FIGS. 8a through 8c are schematic diagrams of a typical electrochemical test strip that forms the basis for many commercially available glucose biosensors. In FIG. 8a, there are two electrodes 355, each of which is connected to leads 350 that interface with the electronics of the meter. The electrodes 355 and leads 350 may be coupled to a support substrate 375. In this example, the test strip uses a commonly used 2-electrode configuration. In FIG. 8a, the sample 360 completely covers both electrodes, ensuring that the entire electrode area of each electrode is in contact with the sample. In FIG. 8b, sample 370 covers one electrode completely but partially covers the other electrode. In FIG. 8c, sample 365 partially covers both electrodes.
FIG. 9 illustrates partial coverage of electrodes by a sample for a different geometry of electrodes. In this example, an electrochemical test strip is made with two electrodes facing each other in a parallel plate design. Electrode 400 and electrode 405 are supported by a solid substrate material 420. Sample 410 fills the sample chamber and covers both electrode areas fully. Sample 415, however, only partially covers both electrode areas and results in a system of reduced effective electrode area. Such incomplete coverage of the electrode surface can be a result of partial filling of the sample chamber. In one example, diabetic patients that make blood glucose measurements must often use such electrochemical test strips to make measurements of blood glucose. In such cases, if enough blood does not enter into the sample chamber, incomplete coverage of the electrode system can result, yielding inaccurate glucose estimates. Thus, a method to assess the effective electrode area that is independent of the analyte concentration would be useful.
Furthermore, the volume of sample that enters into the test strip can be estimated. Referring to FIG. 9, if the three dimensions of the sample chamber that contains sample 415 are known, then the volume of sample 415 can be estimated by scaling the total geometric volume of the sample chamber by the fractional amount of the electrode coverage. In one example, the total volume of the sample chamber is 100 nL. If sample 415 is determined to cover 75% of the electrode 405, then one estimate of the volume of sample 415 would be (0.75)*100 nL=75 nL. The estimate of the sample volume would be useful when making measurements that depend on knowing the volume of the sample in the electrochemical cell. One example of where this knowledge would be useful is in coulometry.
FIG. 4 illustrates the problem of electrode fouling with electrochemical sensors. Electrode fouling, also called sensor fouling, is a term that describes material 320 adhering, adsorbing, or otherwise coating all or part of the electrode 310. In this example, the analyte is ferrocyanide 300 which must move through the fouling material 320 and then react at the electrode 320 in an oxidation reaction that yields an electronic current 315 in the electrode 310. The product of the reaction is ferricyanide 305 which then moves back out of the fouling material 320. One example of when electrode fouling may occur is during extended use of the sensor in environments that could cause fouling, such as implanting a biosensor into the body or deploying gas sensors in environments containing sulfides. In such situations, as well as other situations that would be apparent to one skilled in the art, material may deposit onto the electrode, causing a distorted signal to be measured. Often, the measured signal intensity decreases as the amount of electrode fouling increases until ultimately the sensor becomes insensitive to the target analyte. In other cases, the fouling material may act as a catalyst for certain chemical reactions and the sensor's response may actually be enhanced. In either case, if the sensor's response is altered due to fouling, then the resulting measurement is inaccurate.
In the calibration curves shown in FIG. 3, data points 470 measure the DC current from samples with different concentrations of ferrocyanide with an electrode that is not fouled. Data points 480 measure the DC current from samples with different concentrations of ferrocyanide with an electrode that is fouled by a coating of 3.33 μg of cellulose acetate. Data points 490 measure the DC current from samples with different concentrations of ferrocyanide with an electrode that is fouled by a coating of 10 μg of cellulose acetate. This example illustrates that the measured DC current signal in this amperometric sensor depends on both the analyte concentration and the extent of electrode fouling. Thus, a low DC signal may be the result of either low analyte concentration or due to increased electrode fouling. Thus, a means to determine the extent of electrode fouling which is independent of analyte concentration would be useful. Such a method could then be used to adjust the measured current signal and correct for signal distortion caused by electrode fouling.
Although the previous two examples were illustrated with amperometric sensors, one of ordinary skill in the art will recognize the application to potentiometric sensors. Potentiometric sensors also rely on analyte coming into the proximity of the electrode.
Thus, when electrochemical means of detection are used, the environmental factors—including the properties of the sample that contain the analyte—may heavily influence the signal that is measured. Such factors may introduce inaccuracies into the measurement, including but not limited to, change in calibration and change in sensitivity. Hence a method and apparatus for detecting properties of the environment that may affect the measured signal, including dielectric constant of the sample or the electrode, effective electrode area, and ionic strength of the sample, would benefit electrochemical sensor systems and may allow for corrections to be made to the estimated analyte concentration, calculated from the measured signal, based on the information about the environmental factors.

Method and apparatus for assay of electrochemical properties


A multi-layer structure (102) includes a first build-up layer structure (202) configured to connect to a heat-generating module (120), a second build-up layer structure (206) configured to connect to a substrate, and a middle layer (204) provided between the first build-up layer structure and the second build-up layer structure, the middle layer including at least one semiconductor component (110) and a heat spreader (130). A first set of thermal vias (210) extend through the first build-up layer structure to the heat spreader, and a second set of thermal vias (2100 extend through the second build-up layer structure to the heat spreader, wherein at least a portion of the first set of thermal vias is in thermal contact with the heat-generating module.

Semiconductor devices continue to decrease in size and increase in power-density, resulting in a number of challenges for system designers. One of the primary challenges relates to microelectronic device cooling—i.e., how to efficiently remove heat generated by the device during operation.
Traditional multi-layer high-density interconnects (HDI) typically have an organic substrate and are soldered to a printed circuit board (PCB) such that the heat-generating chips have an efficient heat transfer path to the board. In advanced multi-layer embedded chip packages, however, it is possible to incorporate one or more semiconductor devices (e.g., memory devices) within or on top of one or more build-up layers containing vias, dielectrics, etc., which are held together in an integrated package by encapsulants and the like. Because of the thermal boundary conditions presented by such interconnect structures, it is difficult to attach power amplifiers and other high-power components in such a way that heat from these power devices can be dissipated efficiently. That is, as such multi-layer embedded chip packages consist of low thermal conductivity layers of dielectric with sparsely-distributed metal interconnects and electrical vias, their effective thermal resistance is very high. It is therefore undesirable to stack high-power amplifiers, microprocessors, and other components on these multi-layer structures.
Accordingly, there is a need for methods and structures that improve heat transfer in embedded chip packages by overcoming these and other shortcomings of the prior art. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.

Methods and apparatus for thermal management in a multi-layer embedded chip structure


The invention provides a phase change type optical recording medium enabling an increased jitter concomitant with repeated overwriting to be restrained or substantially eliminated. In the optical recording medium comprising a phase change type recording layer on a substrate, the recording layer has a lower dielectric layer in contact with a lower side thereof and an upper dielectric layer in contact with an upper side thereof, and at least one of the upper and lower dielectric layers contains zinc sulfide, and further includes a metal element A that has a standard free energy for forming a sulfide thereof lower than a standard free energy for forming ZnS at 0 to 1,000.degree. C. The ratio of metal element A to all metal elements in the zinc sulfide-containing dielectric layer is less than 2 at %. Metal element A is typically Ce, Ca, Mg, Sr, Ba, and Na.

The present invention relates to a phase change type optical recording medium, and its fabrication method.
Highlight is recently focused on optical recording media capable of recording information at a high density and erasing the recorded information for rewriting or overwriting. One typical rewritable optical recording medium is of the phase change type wherein the recording layer is irradiated with laser beam to change its crystallographic state whereupon a change of reflectance by the crystallographic change is detected for reading. Optical recording media of the phase change type are of great interest since they can be overwritten by modulating the intensity of a single light beam and the optical system of the drive unit used for their operation is simpler as compared with magneto-optical recording media.
Most optical recording media of the phase change type use Ge--Te base materials which provide a substantial difference in reflectance between crystalline and amorphous states and have a relatively stable amorphous state. In recent years, it has been proposed to use compounds known as chalcopyrites.
Chalcopyrite compounds are extensively investigated as compound semiconductor materials, and applied to solar batteries and the like. The chalcopyrite compounds are composed of Ib-IIIb-VIb.sub.2 or IIb-IVb-Vb.sub.2 as expressed in terms of the Groups of the Periodic Table and have two stacked diamond structures. The structure of chalcopyrite compounds can be readily determined by X-ray structural analysis and their basic characteristics are described in Physics, Vol. 8, No. 8 (1987), page 441, Denki Kagaku (Electrochemistry), Vol. 56, No. 4 (1988), page 228, and other literature.
Among the chalcopyrite compounds, AgInTe.sub.2 is known to be applicable as a recording material by diluting it with antimony or Sb or bismuth or Bi. The resulting optical recording media are generally operated at a linear velocity of about 7 m/s. See JP-A's 3-240590, 3-99884, 3-82593, 3-73384 and 4-151286.
In addition to these phase change type optical recording media using chalcopyrite compounds, JP-A's 4-267192, 4-232779 and 6-166268 disclose phase change type optical recording media wherein an AgSbTe.sub.2 phase forms upon the crystallization of a recording layer.
When information is recorded on a phase change type optical recording medium, the recording layer is irradiated with laser beam of power (recording power) high enough to bring the recording layer to a temperature higher than the melting point thereof. The recording layer is melted at spots with the recording power applied thereon, and then quickly cooled so that recorded marks of amorphous nature can be formed. When the recorded marks are erased, on the other hand, the recording layer is irradiated with laser beam having such a relatively low power (erasing power) as to bring the temperature of the recording layer to a temperature higher than that the crystallization temperature thereof but lower than the melting point thereof. The recorded marks with the erasing power applied thereon go back to the amorphous state because they are slowly cooled down after heated to the temperature higher than their crystallization temperature.
In the phase change type optical recording medium, dielectric layers are formed on both sides of the recording layer. Requirements for these dielectric layers are that:
(1) they can protect the recording layer or substrate against thermal hysteresis due to irradiation with laser beam,
(2) they can amplify reading signals making use of the interference effect of light reflected at the interface of each layer, and
(3) their thermal conductivity, etc. can be properly regulated to regulate record/erase characteristics.
For a dielectric layer meeting such requirements, a dielectric layer composed mainly of ZnS having a high refractive index is often used. For instance, JP-A 63-103453 discloses an optical information recording medium having a dielectric layer comprising a mixture of ZnS and SiO.sub.2. The publication states that among the advantages of the invention there are an increase in the sensitivity to incident light power upon recording, and an increase in the number of repetition of write/read cycles to which the dielectric material is exposed, and goes on that the sensitivity increase is due to the optimization of the heat constant of the dielectric layer, and the increase in the number of repetition of write/read cycles is due to the prevention of denaturation of the dielectric layer. JP-A 4-114330, too, discloses an optical information recording medium having a dielectric layer comprising a mixture of a compound selected from the group consisting of ZnS, etc., and a compound selected from the group consisting of Ta.sub.2 O.sub.5, etc. The publication alleges that among the advantages of the invention there are excellent humidity resistance, less defects, and no interlaminar separation.
According to experiments conducted by the inventors, however, it has been found that when a ZnS-containing dielectric material is used for the dielectric layers of the phase change type optical medium, repeated overwriting gives rise to some considerable jitters, which in turn bring about a considerable reduction in the number of repetition of write/read cycles. According to TDS analysis of a ZnS--SiO.sub.2 dielectric layer, it has also been found that, upon included in the form of a simple substance or dimer in the dielectric layer during its formation, sulfur is isolated and sublimed from the dielectric layer by heating to about 400.degree. C. This temperature is close to the melting point of the recording layer. Thus, the sulfur is diffused from within the dielectric layer into the recording layer upon recording, resulting in a change in the composition of the recording layer. Such actions lead to a decrease in the rate of erasure or fluctuations in the distance between recorded marks, which are believed to be attributable to the increased jitters due to repeated overwriting.

Optical recording medium, and its fabrication method


The present invention features a method of treating leptomeningeal carcinomatosis in a subject using a peptide-therapeutic conjugate as exemplified by the agent ANG1005.

Leptomeningeal carcinomatosis (LC) is a rare complication of cancer in which the disease spreads to the membranes (meninges) surrounding the brain and spinal cord. LC occurs in approximately 5% of people with cancer and is usually terminal. If left untreated, median survival is 4-6 weeks; if treated, median survival is 2-3 months. LC may occur at any stage of cancer, either as a presenting sign or as a late complication, although it is associated frequently with relapse of cancer elsewhere in the body.
LC is generally considered incurable and is difficult to treat. Treatment goals generally include improvement or stabilization of the patients neurologic status, prolongation of survival, and palliation. Thus, there is a need for therapeutics and therapeutic regimens capable of treating LC.

Methods for the treatment of leptomeningeal carcinomatosis


The invention relates to a multi-layer decoupling and sealing system (1), in particular for the laying of ceramic paving (10) according to a thin-bed method (12). Said system comprises a layered construction containing, from the base upwards, a liquid-impermeable sealing layer (4), an anchorage layer (2, 3) that is configured from a lattice-type structural element and that is used to hold a filler material (12), which is to be incorporated into the upper face of the decoupling and sealing system (1) and which is plastic during processing and subsequently cures, in addition to a reinforcement layer (5), which is fixed, at least in some sections, to the anchorage layer (2, 3). This improves the load-bearing capacity of the decoupling and sealing system (1) and the bonding properties of ceramic paving (10) that is laid in a conventional manner on the decoupling and sealing system (1).

Today, ceramic paving, in particular ceramic tiles, is usually laid using the so-called thin-bed method, in which the ceramic paving is laid in a thin, adhesive layer of tile mortar. This method, which is satisfactory for interior applications, is problematic when ceramic paving is to be laid in an exterior area, because the effects of moisture and temperature on paving of this kind frequently result in the gradual destruction of the tiles or the base in which they are laid, and it becomes impossible to avoid the diminished reliability of this type of paving, with the result that costly repair work may be required. Moisture that penetrates through the tile paving into the substratum frequently results in damage to the building itself because the moisture cannot escape easily. This occurs frequently in the case of balconies that are to be sealed.
In addition to the foregoing, it is difficult to control the crack behaviour of the ceramic paving and of the substratum because of the very different coefficients of expansion of the substratum, the thin-bed mortar, and the ceramic paving, which are brought about by the very high temperature differences between the high temperatures caused by solar radiation and the low temperatures caused by frost that occur in the exterior area. For this reason, there is frequently cracking in the tile paving if it is joined rigidly to the substratum.
For this reason, it has frequently been proposed that ceramic paving of this type that is laid in an exterior area can be laid in a more durable fashion in that the ceramic paving is deliberately decoupled from the substratum. It is true that such decoupling ensures that mechanical decoupling is effected transversely to the area that is paved; it also entails the disadvantage that the mechanical load-bearing capacity of the tile paving is inadequate. On the one hand, the tiles are not anchored firmly enough to the decoupling system, and on the other hand, the pressure strength of the decoupling system itself is not optimal.
This type of configuration for a decoupling and sealing system is described in DE 100 60 751 C1. In this configuration, what is proposed is a decoupling and sealing system that has a plastic or bitumen layer underneath, above which are disposed a first non-woven layer that is of a first hydrophobic polymer; above this there is a drainage layer that is of a second hydrophobic polymer, and then, above this, a second non-woven layer that is of the first hydrophobic polymer. It is true that, within certain limits, this layered construction permits moisture that has penetrated to drain out of the substratum of a tile layer; however, the mechanical load-bearing capacity of a layered, construction of this kind is unsatisfactory since embedding the uppermost non-woven layer in the tile mortar does not permit adequate anchoring or reinforcing function. The drainage layer is in the form of a lattice-type layer, although no exact details for forming the lattice-type layer are provided.
For this reason, it is the objective of the present invention to so develop a multilayer decoupling and sealing system of this type such that an improvement of the mechanical load-bearing capacity and anchoring to the tile layer can be achieved.
This objective has been achieved by the distinguishing features set out in Patent Claim 1 in conjunction with the features set out in the preamble. Further advantageous embodiments of the present invention are set out in the secondary claims.

Multi-layer decoupling and sealing system


A yeast cell with reduced pyruvate to oxaloacetate conversion activity, and a method of producing lactate using the yeast cell.

1. Field
The present disclosure relates to a yeast cell with inactivated or depressed pyruvate carboxylase and a method of producing lactate using the yeast cell.
2. Description of the Related Art
Lactate is an organic acid that is broadly used in various industrial fields, such as food, pharmaceutics, chemicals, and electronics. Lactate is colorless, odorless, and a low-volatile material that dissolves well in water. Lactate is non-toxic to the human body and thus may be used as a flavor agent, a taste agent, or a preserving agent. Also, lactate is an environment-friendly alternative polymer material and a raw material of a polylactic acid (PLA) that is biodegradable plastic.
PLA is a polyester-based resin that is produced by ring-open polymerizing a dimer, i.e., lactide, which has been converted from lactic acid and may be variously processed into a film, sheet, fiber, plastic, etc. Thus, demands for PLA as bioplastic have recently increased to broadly replace conventional typical petrochemical plastic, such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), or polystylene (PS).
In addition, lactate includes both a hydroxyl group and a carboxyl group at the same time and thus is highly reactive. Accordingly, lactate is easily converted into an industrially important compound, such as lactate ester, acetaldehyde, or propyleneglycol, and thus has received attention as an alternative chemical material of the next generation in chemical industry.
Currently, lactate is produced by an industrially petrochemical synthesis process and a biotechnological fermentation process. The petrochemical synthesis process is performed by oxidizing ethylene derived from crude oil, preparing lactonitrile through addition of hydrogen cyanide after acetaldehyde, purifying by distillation, and hydrolyzing by using chloric acid or phosphoric acid. Also, the biotechnological fermentation process is used to manufacture lactate from a reproducible carbon hydrate, such as, starch, sucrose, maltose, glucose, fructose, or xylose, as a substrate.
Therefore, a strain for efficiently producing lactate and a lactate production method using the strain are needed.

Yeast cell with inactivated or depressed pyruvate carboxylase and method of producing lactate using the yeast cell


A camera with a red-eye preventing feature includes an operation unit for causing the red-eye phenomenon preventing feature to function, a timer for measuring a predetermined period when the red-eye phenomenon preventing feature functions, an indicating device for indicating the state of the timer, and an exposure unit for performing an exposure operation. The exposure unit can perform the exposure operation even during the predetermined time period.

1. Field of the Invention
The present invention relates to a camera, and more particularly, to an improvement in a camera provided with a feature for preventing a red-eye phenomenon occurring in flash photography.
2. Description of the Related Art
Recently, a large number of cameras are provided with a feature for preventing the red-eye phenomenon that occurs when a person or an animal is photographed using a flash. When such flash photography is performed by using this kind of camera, in order to prevent the red-eye phenomenon, it is necessary to turn on a red-eye phenomenon preventing lamp and to wait for about 1.2 sec. before an exposure operation is started. Thus, during this waiting time, there is a possibility of missing a photographic opportunity.
In order to solve this kind of problem, a camera is proposed which has a switch for selecting whether to operate the red-eye phenomenon preventing feature.
A camera having a red-eye phenomenon preventing selecting operation switch such as above-described is advantageous with respect to being capable of selecting whether to operate the red-eye phenomenon preventing feature in accordance with user's own will, but the user must operate the red-eye phenomenon preventing selecting operation switch in addition to a shutter release button for every photograph. Consequently, its operation is less convenient, the operational time increases resulting in missing a photographic opportunity, and the cost is increased because of the addition of the switch.

Camera provided with red-eye phenomenon preventing feature


A proximity sensor includes a capacitive touch controller. A first shielding area is coupled to a first shield terminal of the capacitive touch controller. A second shield area is coupled to a second shield terminal of the capacitive touch controller. A first sensing element is disposed adjacent to the first shielding area. The first sensing element is coupled to a first sensing terminal of the capacitive touch controller. A second sensing element is disposed adjacent to the second shielding area. The second sensing element is coupled to a second sensing terminal of the capacitive touch controller. The capacitive touch controller is configured to associate the first sensing element with the first shielding area. A self-capacitance of the first sensing element is measured while the second shielding area is inactive. The self-capacitance of the first sensing element is measured at a first frequency.

Smartphones and other mobile devices have rapidly become ubiquitous throughout the world. Mobile phones and tablet computers are commonly seen in use at restaurants, in waiting rooms, or on street corners. Mobile devices are used for gaming, photography, listening to music, social networking, or simply talking with another person via a built-in microphone and speaker.
Mobile devices enrich lives by keeping family and friends in communication, allowing any moment to be captured as a photo or video, and providing a means of contacting someone in an emergency situation. FIG. 1a illustrates a mobile device 10. Mobile device 10 is a touchscreen slate cellular (cell) phone. In other embodiments, mobile device 10 is a tablet computer, pager, GPS receiver, smartwatch or other wearable computer, laptop computer, handheld game console, or any other device utilizing capacitive proximity or touch sensing.
Mobile device 10 includes proximity sensor 11. Proximity sensor 11 detects the distance of a user from a front face of mobile device 10. Proximity sensor 11 uses the self-capacitance of a sensing element to determine whether a user is in proximity. Proximity sensor 11 also determines the distance of the user from the front face of mobile device 10. Self-capacitance of the sensing element changes as a user's body part moves nearby proximity sensor 11. The operating system of mobile device 10 is programmed to react when proximity sensor 11 reports a user is in proximity to the mobile device. In one embodiment, radio frequency (RF) output power of mobile device 10 is reduced when a user is in proximity of the mobile device to prevent exceeding specific absorption rate (SAR) regulations. SAR is a measure of the rate at which energy is absorbed by the human body when exposed to an RF electromagnetic field.
Mobile device 10 includes touchscreen 12 on a front side of the mobile device. Touchscreen 12 is used to display a graphical user interface (GUI). The GUI on touchscreen 12 presents feedback, notifications, and other information to a user as determined by an operating system of mobile device 10. Touchscreen 12 is sensitive to physical touch from body parts of a user of mobile device 10. Touchscreen 12 utilizes resistance, capacitance, acoustic waves, an infrared grid, optical imaging, or other methods to determine the presence and location of a user's touch.
In one common usage scenario of mobile device 10, touchscreen 12 displays a button as a part of the GUI, and a user touches the location of the button on the touchscreen to perform an action associated with the button. In one embodiment, touchscreen 12 displays a 3×4 telephone keypad. A user dials a telephone number on the displayed keypad by touching touchscreen 12 at the locations where the desired numbers to dial are displayed. Touchscreen 12 displays an alphanumeric keyboard along with, or as an alternative to, the telephone keypad, with a user touching the touchscreen in the location of letters, numbers, or symbols to be entered in a text input field displayed on the touchscreen. Touchscreen 12 is also used to watch downloaded or streamed videos, or play games, with a user's touch controlling playback of the video or play of the game. In some embodiments, touchscreen 12 is sensitive to a user's touch when the display component of the touchscreen is disabled. While listening to music, a user pauses the music, or advances to the next track of music, by drawing a symbol on touchscreen 12 even though nothing is displayed on the touchscreen.
Buttons 14 provide an alternative user input mechanism to touchscreen 12. Buttons 14 perform functionality depending on the programming of the operating system running on mobile device 10. In one embodiment, buttons 14 return the GUI on touchscreen 12 to a home screen, go back to a previous GUI screen, or open up a menu on the GUI. In other embodiments, the functionality of buttons 14 changes based on a context displayed on touchscreen 12. In one embodiment, buttons 14 are implemented using proximity sensors similar to proximity sensor 11. A user placing a finger on one of buttons 14 modifies the self-capacitance of a sensing element under the button. When proximity is detected, the proximity sensor for the respective button notifies the operating system of mobile device 10 to execute programming associated with the button press.
Speaker 16 provides audible feedback to a user of mobile device 10. When mobile device 10 receives an incoming message, speaker 16 produces an audible notification sound to alert a user to the received message. An incoming telephone call causes a ringing sound from speaker 16 to alert the user. In other embodiments, a musical ringtone, selectable via the GUI on touchscreen 12, is played via speaker 16 when an incoming telephone call is received. When mobile device 10 is used to participate in a telephone call, a user of the mobile device speaks into microphone 17 while the other conversation participants' voices are reproduced by speaker 16. When a user watches a movie or plays a game, the sound associated with the movie or game is produced by speaker 16 for the user to hear.
Front facing camera 18 provides visual feedback to the operating system of mobile device 10. Camera 18 creates a digital image of the area facing touchscreen 12. Camera 18 is used in video chat applications running on mobile device 10 to capture a user's face during a conversation. Mobile device 10 transmits the video of a user to another mobile device in another location, and receives a streaming video of another person using the other mobile device which is displayed on touchscreen 12. Camera 18 is also used to take selfies or other pictures. When camera 18 is used to take pictures, touchscreen 12 displays the image being captured by the camera so that the touchscreen is an electronic viewfinder. Captured photographs are stored on memory within mobile device 10 for subsequent viewing on touchscreen 12, sharing on social networks, or backing up to a personal computer.
Housing 20 provides structural support and protection for the internal components of mobile device 10. Housing 20 is made of rigid plastic or metallic materials to withstand environmental hazards which cause harm to the circuit boards and other components within mobile device 10 if exposed directly. In one embodiment, a panel of housing 20 opposite touchscreen 12 is removable to expose interchangeable parts of mobile device 10 such as a subscriber identification module (SIM) card, flash memory card, or battery. Housing 20 includes a transparent glass or plastic portion over touchscreen 12, which protects the touchscreen from environmental factors while allowing a user's touch to be sensed through the housing.
FIG. 1b illustrates a user 30 operating mobile device 10 as a telephone. User 30 holds mobile device 10 with speaker 16 over an ear of the user. Microphone 17 is oriented toward a mouth of user 30. When user 30 speaks, microphone 17 detects and digitizes the user's voice for transmission to a person the user is speaking with. The person that user 30 is speaking with transmits a digitized voice signal to mobile device 10 which is reproduced on speaker 16 and heard by the user. User 30 thereby converses with another person using mobile device 10.
When user 30 holds mobile device 10 as illustrated in FIG. 1b, proximity sensor 11 notifies the operating system that the user is in proximity. The operating system of mobile device 10 executes code to reduce RF output, disable touchscreen 12, and perform any other actions as programmed.
FIG. 1c illustrates user 30 touching or pressing a button 14. Pressing buttons 14 performs various actions of the operating system depending on the programming of mobile device 10. In one embodiment, user 30 presses a home button to return the display of touchscreen 12 to a home screen.
Proximity sensor 11 and buttons 14 each operate by measuring the self-capacitance of a corresponding sensing element located within mobile device 10. Self-capacitance of a sensing element increases as an object or a body part of user 30 is moved toward the sensing element. Self-capacitance of a sensing element decreases as an object or a body part of user 30 is moved further away from the sensing element. The self-capacitance of a sensing element is compared against a threshold to determine whether user 30 is in proximity to the sensing element. In other embodiments, the self-capacitance value of a sensing element is converted into a measurement of the distance between mobile device 10 and user 30. Measuring the distance of an object from mobile device 10 in a direction perpendicular to touchscreen 12 is known as z-axis detection.
Capacitive touch sensing utilizes shielding planes under the sensing elements to provide directionality of sensing and reduce interference from noise. The shielding planes for capacitive touch sensing are driven by the integrated circuit (IC) which senses the self-capacitance of the sensing elements. A sensing IC drives shielding planes to approximately the same voltage potential as an associated sensing element when detecting proximity. For proximity and z-axis distance of user 30 to be accurately detected, a sensing IC must be able to maintain a shielding plane near the same voltage as a sensing element. When the voltage of a shielding area and a corresponding sensing element are different, the shielding area contributes to the self-capacitance of the sensing area, thus affecting the proximity reading.
One goal of mobile device manufacturers is to provide capacitive touch sensing in multiple areas of a mobile device. Using more proximity sensors located at different locations allows mobile device manufacturers to implement the advanced functionality that consumers demand. However, when proximity sensing is required at distant areas of mobile device 10, using a single proximity sensing integrated circuit becomes challenging. Proximity sensor ICs available on the market include multiple sensing element terminals, but only a single terminal to connect a shielding plane. Driving multiple shielding planes at distant locations of mobile device 10 with a single shield output reduces the ability of a sensing IC to maintain the shielding planes at a voltage close to the voltage of an individual sensing element. The shield terminal is driving a greater load than is actually necessary for measurement of an individual sensing element. Additionally, RF and other interference from one area of mobile device 10 affects sensing in other areas of the mobile device because of the connection of each shielding area to a common shield terminal of the sensing IC.
Multiple sensing ICs can be used to provide an isolated shielding plane for capacitive touch sensing in each area of mobile device 10. However, using multiple sensing ICs takes up additional space on the circuit boards of mobile device 10. As today's consumers demand smaller and thinner mobile devices, circuit board area becomes more valuable and limited. A second goal of manufacturers is to provide consumers with smaller and lighter mobile devices. Using multiple capacitive sensing ICs also increases costs to the manufacturer.
Capacitive sensing ICs on the market today require a tradeoff between goals of mobile device manufacturers. On the one hand, a manufacturer can use multiple sensing ICs to accurately detect proximity of a user at distant areas of a mobile device. Using multiple sensing ICs increases the size and cost of the mobile device. On the other hand, a mobile device manufacturer can use a single sensing IC which only provides a single shield terminal. A single sensing IC with a single shield terminal provides results with reduced accuracy as more shielding planes are used in more areas of the mobile device. A mobile device 10 with less accurate proximity sensors, or fewer proximity sensors, is not able to provide the advanced functionality of other mobile devices.


Disclosed are Vibrio cholerae comprising a mutated transcriptional regulatory protein (ToxT) amino acid sequence, wherein the mutation results in a reduction in the expression of cholera toxin by the Vibrio cholerae. Also disclosed are Vibrio cholerae comprising a mutated transcriptional regulatory protein (ToxT) amino acid sequence, wherein the mutation results in an increase in transcription of the nucleic acid encoding the mutated ToxT. Vaccines comprising the aforementioned Vibrio cholerae are disclosed. Also disclosed are amino acid sequences that encode a mutated ToxT protein.

1. Field of the Invention
The present invention relates to the fields of infectious disease, vaccines, molecular biology, and the treatment and prevention of cholera.
2. Description of Related Art
Vibrio cholerae is a Gram-negative bacterium that is responsible for the deadly diarrheal disease cholera. The bacterium expresses virulence factors within the human intestine that lead to intestinal colonization and disease symptoms. Two of the most important virulence factors are cholera toxin (CT), an ADP-ribosylating toxin that is largely responsible for the symptoms of disease, and the toxin coregulated pilus (TCP), a type IV pilus essential for intestinal colonization (Gill, 1976; Mekalanos et al., 1983; Pearson and Mekalanos, 1982; Herrington et al., 1988).
ToxT, an AraC family protein, activates the transcription of the genes encoding CT (ctx) and TCP (tcp), as well as the genes encoding other poorly understood "accessory colonization factors" (acf) (DiRita et al., 1991). Since toxT lies within the tcp gene cluster, ToxT is also able to regulate its own expression, allowing for continuous expression of ToxT under favorable conditions (Brown and Taylor, 1995; Yu and DiRita, 1999). V. cholerae strains lacking toxT express no CT or TCP, and fail to colonize the intestine (DiRita et al., 1996; Champion et al., 1997). ToxT binds to specific sites upstream of the ctxA, tcpA, acfa, tagA and aldA promoters (Eithey and DiRita, 2005; Withey and DiRita, 2005; Hulbert and Taylor, 2002) to stimulate transcription. The location of all of these binding sites is at least 45 bp upstream of the transcription startsite, with the exception of the ctxA promoter, where ToxT protects a region up to −13. This suggests that the tcpA, acfA, tagA, and aldA promoters are "Class I" AraC-like promoters (i.e., activated from sites that do not overlap with the −35 element), and consistent with this mode of activation, it has been demonstrated that ToxT-dependent tcpA transcription requires the C-terminal domain of the α subunit of RNAP (Hulbert and Taylor, 2002). However, the overlap of ToxT binding with the −35 element (albeit at lower affinity) at the ctxA promoter may indicate that this represents activation of a "Class II" AraC-like promoter, which has been shown in some AraC-like activators [e.g., RhaS, RhaR, MelR] (Wickstrum and Egan, 2004; Grainger et al., 2004) to involve contacts between the activator and σ70.
Recently, a "toxbox" motif (yrTTTTwwTwAww) has been identified within the ToxT-bound region at ToxT-activated promoters (Withey and DiRita, 2006). At all ToxT-activated promoters with the exception of aldA, two toxbox sequences are found in either a direct or inverted orientation. It has been shown that the insertion of 5 bp and 10 bp between the two toxboxes found at the acfa and tcpA promoters prevents transcriptional activation, but still allows ToxT binding in vitro (Withey and DiRita, 2005; Withey and DiRita, 2006). These results suggest that single ToxT monomers bind each toxbox, and that interactions between monomers are likely important for transcriptional activation.
AraC family members are classified based on homology to a 99 amino acid stretch within the AraC carboxy-terminus (Gallegos et al., 1997). The crystal structures of two AraC family proteins, MarA and Rob, complexed with DNA, have been resolved and the structures demonstrated that this region encodes two distinct helix-turn-helix (HTH) motifs that function in DNA-binding (Gallegos et al., 1997; Rhee et al., 1998; Kwon et al., 2000). MarA, Rob, and another protein, SoxS, are all able to bind to the same promoter elements (alternatively referred to as marbox/robbox/soxbox) and activate an overlapping set of genes, albeit with different affinities (Jair et al., 1996; Jair et al., 1995; Greenberg et al., 1990). The crystal structure of MarA bound to the mar promoter identified base- and phosphate backbone-specific contacts made between the first HTH (HTH1) and the 4 bp recognition element (RE)1 motif of the marbox, and specific contacts made between HTH2 and the 4 bp RE2 motif; RE1 and RE2 are centered on the same face of the DNA helix and separated by a 7 bp A/T-rich spacer. However, alanine substitution mutagenesis of MarA has suggested that while both HTH motifs contribute to DNA binding, the individual contributions of contacts made between HTH1 and RE1 are more important to DNA binding than HTH2-RE2 contacts (Gillette et al., 2000), and similar conclusions were drawn from alanine substitution mutagenesis of SoxS (Griffith and Wolf, 2002). Moreover, the crystal structure of Rob bound to the micF promoter indicated base- and phosphate backbone-specific contacts between HTH1 and RE1, similar to those found in the MarA-mar structure, but no base-specific contacts between HTH2 and RE2 and only one specific contact to the phosphate backbone (Kwon et al., 2000). It has been shown that bile acids interact with Rob to induce transcription (Rosenberg et al., 2003), so perhaps the apparent lack of specific contacts between HTH2 and RE2 may be due to a lack of inducer during crystallization. Studies of DNA binding by several AraC family members including AraC, MelR, RhaS, SoxS, and MarA have indicated that the orientation of the promoter-proximally bound activator depends on the distance to the −35 element, with the HTH2 oriented closest to the −35 element at Class II-like promoters (where the activator binding site extends downstream to at least −40) and with HTH1 oriented closest to the −35 element when the binding site is further upstream of the −35 element (Grainger et al., 2004; Porter and Dorman, 2002; Grainger et al., 2003; Behnde and Egan, 1999; Niland et al., 1996; Martin and Rosner, 2001; Martin et al., 1999; Wood et al., 1999).
The amino-terminus of AraC is responsible for dimerization and binding of the effector arabinose (Bustos and Schleif, 1993). The crystal structure of the amino terminus of AraC has also been resolved and revealed arabinose bound within an eight-stranded anti-parallel beta barrel "jelly roll" structure at the N-terminal end, and an antiparallel coiled-coil that mediates dimerization at the C-terminal end of this domain (Soisson et al., 1997). In general the N-termini of AraC family proteins (if present) do not share significant sequence homology, but they often share similar functions with the AraC N-terminus, such as oligomerization and/or effector binding (Gallegos et al., 1997; Martin and Rosner, 2001).
ToxT, like AraC, appears to contain two distinct domains: an N-terminal domain involved in dimerization and possibly environmental sensing, and a C-terminal domain necessary for DNA binding (Prouty et al., 2005). The ToxT N-terminus fused to the DNA binding domain of LexA is able to repress sulA transcription, consistent with dimerization determinants being located within the N-terminal domain. The ToxT N-terminus shares little sequence homology with the AraC N-terminus, but it is predicted to share secondary and tertiary structural similarities, as determined by Threading programs (Soding et al., 2005) (discussed below). Two different mutant forms of the N-terminus were identified that exhibited altered responses to the repressive effects of bile, suggesting that there are environmentally responsive elements within the N-terminus. The ToxT C-terminus is able to bind DNA, but only when fused to a heterologous dimerization domain, demonstrating that the C-terminus is sufficient for DNA binding, and that the C-terminus requires dimerization for DNA binding. Interestingly, the dimerized C-terminus is unable to activate transcription, suggesting that, unlike AraC and several other family members (Bustos and Schleif, 1993; Poore et al., 2001 there may be additional determinants in the ToxT N-terminus required for transcriptional activation.
This invention concerns the identification of amino acids critical for ToxT function. Specific amino acids involved in dimerization, DNA binding, and environmental modulation of ToxT have been identified. This information can be applied in the prevention and treatment of cholera.

Identification of residues critical for the function of the vibrio cholerae virulence regulator ToxT by scanning alanine mutagenesis

The Board of Regents of the University of Texas System


A memory sub-system and a method for operating the same. The memory sub-system includes (a) a main memory, (b) an ECC circuit, (c) a hard fail identifier circuit, (d) a repair circuit, (e) a redundant memory, and (f) a threshold setting circuit. The ECC circuit is capable of (i) detecting a first bit fail, (ii) sending an error flag signal to the hard fail identifier circuit, (iii) sending a first location address, a first bit location of the first bit fail, and a repaired data from the first location address to the hard fail identifier circuit. The hard fail identifier circuit is capable of (i) determining the number of times of failure occurring at the first bit fail, (ii) determining whether the number of times of failure is equal to a predetermined threshold value, and (iii) if so, sending a threshold reached signal.

1. Technical Field
The present invention relates to memory hard failure repair, and more specifically, to hard failure repair during normal operation using an ECC (Error Correction Code) circuit and a hard fail identifier circuit.
2. Related Art
Prior art exists which covers detection and repair of hard failures in a memory device during the manufacturing process (i.e., at time zero). Prior art also exists which covers detection and correction of soft errors in a memory device during normal operation (e.g., Error Correction Code). Prior art also exists which covers memory error detection and address disable or device replacement during normal operation. There is a need for a subsystem (and a method for operating the same) in which hard failures are detected and repaired during normal operation of a memory device.

Repair of memory hard failures during normal operation, using ECC and a hard fail identifier circuit

International Business Machines Corporation


A method for forming a stack DRAM cell with CUB wherein coupling noise is eliminated is described. Bit-lines are formed according to one of three methods. In a first method, a first pair of bit-lines is fabricated in a first metal layer and a second pair of bit-lines is fabricated in a second metal layer separated from the first metal layer by an insulating layer wherein the first pair of bit-lines is horizontally spaced from the second pair of bit-lines. In a second method, a first of each pair of bit-lines is fabricated in a first metal layer and a second of each pair of bit-lines is fabricated in a second metal layer separated from the first metal layer by an insulating layer wherein the first of each pair of bit-lines is horizontally spaced from the second of each pair of bit-lines. In a third method, each bit-line is divided into segments. First segments of a bit-line are fabricated in a first metal layer and alternating segments of the bit-line are fabricated in a second metal layer separated from the first metal layer by an insulating layer wherein for each pair of bit-lines, facing segments of a first and second of the bit-line pair are fabricated in different metal layers wherein the first of each pair of bit-lines is horizontally spaced from the second of each pair of bit-lines.

(1) Field of the Invention
The present invention relates to the fabrication of integrated circuit devices, and more particularly, to a method of eliminating coupling capacitance between bit-lines in a stack DRAM cell with capacitor under bit-line (CUB) in the fabrication of integrated circuits.
(2) Description of the Prior Art
The popular 1-transistor (1T) dynamic random access memory (DRAM) cell is composed of a pass transistor (for switching) and a storage capacitor. The state-of-the-art DRAM cell has typically either a stacked capacitor or a trench capacitor; referred to as xe2x80x9cstack cellxe2x80x9d or xe2x80x9ctrench cellxe2x80x9d, respectively. Among stack cells, the capacitor can be fabricated either above or below the bit-line, referred to as Capacitor Over Bit-line (COB) or Capacitor Under Bit-line (CUB) structures. All of these cell structures are popular in current manufacture of 16 Mb and 64 Mb DRAM. U.S. Pat. No. 6,048,767 to Terada and U.S. Pat. No. 5,700,731 to Lin et. al. disclose COB schemes.
In integrated circuit manufacture, embedded dynamic random access (DRAM) devices have both memory cells and logic cells formed on a single silicon chip. The stack DRAM with CUB is preferred for embedded DRAM applications, since capacitors can be fabricated before logic transistors (for avoiding thermal cycle effect on logic transistors) and the metal bit-line can be shared with logic circuits. The conventional bit-lines of stack DRAM with CUB scheme are fabricated at the same metal level (e.g. M1) with minimum line and spacing design rules. U.S. Pat. No. 5,893,734 to Jeng et al discloses such a scheme. There is coupling capacitance within each bit-line pair (BL and BL-bar) as well as from adjacent bit-lines. The stack cell with CUB scheme indeed has drawbacks of larger bit-line to bit-line coupling noise (See xe2x80x9cA New DRAM Cell Structure with Capacitor-Equiplanar-to-Bitline (CEB) for Bit-line Coupling Noise Eliminationxe2x80x9d by L. Chang et al, 1998 International Conference on Solid-State and Integrated-Circuit Technology (ICSICT""98), p. 428-431, October 1998) and larger cell size than the stack cell with COB scheme, based on the same design rules. For these reasons, the COB scheme is preferred by stand-alone or commodity DRAM (See xe2x80x9cDRAM Technology Perspective for Gigabit Eraxe2x80x9d by K. Kim et al, IEEE Transactions Electron Devices, V. 45, No. 3, p. 598-608, 1998 and xe2x80x9cLimitations and Challenges of Multi-gigabit DRAM Chip Designxe2x80x9d by K. Itoh et al, IEEE Journal of Solid-State Circuits, V. 32, No. 5, p. 624-634, 1997), although the CUB scheme is preferred by embedded DRAM applications.
There are conventional ways for bit-line coupling noise reduction, e.g. using twisted bit-line. Some of these methods are disclosed in xe2x80x9cTwisted Bit-line Techniques for Multi-gigabit DRAMsxe2x80x9d by D. Min et al, IEE Electronics Letters, V. 33, No. 16, P. 1380, 1997 and xe2x80x9cTwisted Bit-line Architectures for Multi-megabit DRAMsxe2x80x9d by H. Hidaka et al, IEEE Journal of Solid-State Circuits, V. 24, No. 1, p. 35-42, 1989. U.S. Pat. No. 6,140,704 to Kang et al and U.S. Pat. No. 5,625,585 to Ahn et al show twisted bit-line layouts. One drawback of the twisted bit-line technique is its larger size for implementation. However, in the embedded DRAM process, multi-layer metal is available for both logic and DRAM. Thus, the bit-line inter-connect can utilize multi-level metal for no increase of process complexity. A new bit-line interconnect scheme is proposed in which bit-lines are fabricated in an alternating manner at multiple metal layers.
Accordingly, it is a primary object of the present invention to provide an effective and very manufacturable method for forming a stack DRAM cell with capacitor under bit-line (CUB) in the fabrication of integrated circuits.
It is a further object of the invention to provide a process for forming a stack DRAM cell with CUB wherein coupling noise is eliminated.
Another object is to provide a process for forming a stack DRAM cell with CUB for use in stand-alone or embedded DRAM wherein coupling noise is eliminated.
Yet another object is to provide a process for forming a stack DRAM cell with CUB wherein coupling noise is eliminated by alternating metal levels by bit-line pairs.
A further object is to provide a process for forming a stack DRAM cell with CUB wherein coupling noise is eliminated by alternating metal levels by each bit-line.
A still further object is to provide a process for forming a stack DRAM cell with CUB wherein coupling noise is eliminated by alternating metal levels within a bit-line.
Yet another object is to provide a process for forming a stack DRAM cell with CUB wherein coupling noise is eliminated by alternating metal levels by bit-line pairs with metal shielding between bit-lines.
Another further object is to provide a process for forming a stack DRAM cell with CUB wherein coupling noise is eliminated by alternating metal levels by each bit-line with metal shielding between bit-lines.
Another still further object is to provide a process for forming a stack DRAM cell with CUB wherein coupling noise is eliminated by alternating metal levels within a bit-line with metal shielding between bit-lines.
In accordance with the objects of the invention, a method for forming a stack DRAM cell with CUB wherein coupling noise is eliminated is achieved. A capacitor node contact junction and a plurality of bit-line junctions are provided in a semiconductor substrate. A capacitor is formed overlying the semiconductor substrate and connected to the capacitor node contact junction by a contact plug through a first insulating layer. A second insulating layer is deposited overlying the capacitor. A plurality of metal plugs is formed through the second and first insulating layers each contacting one of the plurality of bit-line junctions. Now, bit-lines are formed according to one of three methods.
In a first method, bit-lines are formed each contacting one of the plurality of metal plugs wherein a first pair of bit-lines is fabricated in a first metal layer overlying the second insulating layer and wherein a second pair of bit-lines is fabricated in a second metal layer separated from the first metal layer by a third insulating layer and wherein the second pair of bit-lines contacts one of the metal plugs by a via plug through the third insulating layer and wherein the first pair of bit-lines is horizontally spaced from the second pair of bit-lines.
In a second method, bit-lines are formed, each contacting one of the plurality of metal plugs wherein a first of each pair of bit-lines is fabricated in a first metal layer overlying the second insulating layer and wherein a second of each pair of bit-lines is fabricated in a second metal layer separated from the first metal layer by a third insulating layer and wherein the second of each pair of bit-lines contacts one of the metal plugs by a via plug-through the third insulating layer and wherein the first of each pair of bit-lines is horizontally spaced from the second of each pair of bit-lines.
In a third method, bit-lines are formed, each contacting one of the plurality of metal plugs wherein each bit-line is divided into segments and wherein first segments of a bit-line are fabricated in a first metal layer overlying the second insulating layer and wherein alternating segments of the bit-line are fabricated in a second metal layer separated from the first metal layer by a third insulating layer and wherein for each pair of bit-lines, facing segments of a first and second of the bit-line pair are fabricated in different metal layers and wherein the segments of each bit-line in the second metal layer contact one of the metal plugs by a via plug through the third insulating layer and wherein the first of each pair of bit-lines is horizontally spaced from the second of each pair of bit-lines. This completes fabrication of a DRAM with capacitor under bit-line (CUB) cell in an integrated circuit device.

Bit-line interconnection scheme for eliminating coupling noise in stack DRAM cell with capacitor under bit-line (CUB) in stand-alone or embedded DRAM

Taiwan Semiconductor Manufacturing Company


A hydraulic tensioner is designed for low cost and ease of manufacturing. A piston housing has a bore and a bore cup member received within the bore. A piston is slidably received within the bore cup member, forming a high pressure fluid chamber with the bore cup member. The piston housing can be constructed of inexpensive materials such as aluminum or plastic. The piston and bore cup member are constructed of drawn metal. A single channel connects the pressure chamber to an external source of fluid, and a single valve system regulates the flow of fluid into the pressure chamber. The inexpensive materials and simple design provide for a low cost hydraulic tensioner.

A tensioning device, such as a hydraulic tensioner, is used as a control device for a power transmission chain, or similar power transmission device, as the chain travels between a plurality of sprockets. In this device, the chain transmits power from a driving shaft to a driven shaft, so that part of the chain is slack and part of the chain is tight. Generally, it is important to impart and maintain a certain degree of tension in the chain to prevent noise, slippage, or the unmeshing of teeth in the case of a toothed chain.
Prevention of such slippage is particularly important in the case of a chain driven camshaft in an internal combustion engine because jumping of teeth will throw off the camshaft timing, possibly causing damage or rendering the engine inoperative. However, in the harsh environment of an internal combustion engine, various factors can cause fluctuations in the chain tension.
For instance, wide variations in temperature and thermal expansion coefficients among the various parts of the engine can cause the chain tension to vary between excessively high or low levels. During prolonged use, wear to the components of the power transmission system can cause a decrease in chain tension. In addition, camshaft and crankshaft induced torsional vibrations cause considerable variations in chain tensions. Reverse rotation of an engine, occurring for example in stopping or in failed attempts at starting, can also cause fluctuations in chain tension. For these reasons, a mechanism is desired to remove excessive tensioning forces on the tight side of the chain and to ensure the necessary tension on the slack side of the chain.
Hydraulic tensioners are a common method of maintaining proper chain tension. In general, these mechanisms employ a lever arm that pushes against the chain on the slack side of the power transmission system. This lever arm must push toward the chain, tightening the chain, when the chain is slack, and must be very rigid when the chain tightens.
To accomplish this result, a hydraulic tensioner typically comprises a rod or cylinder as a piston, which is biased in the direction of the chain by a tensioner spring. The piston is housed within a cylindrical piston housing, having an interior space which is open at the end facing the chain and closed at the other end. The interior space of the piston housing contains a pressure chamber in connection with a reservoir or exterior source of hydraulic fluid. The pressure chamber is typically formed between the piston housing and the piston, and it expands or contracts when the piston moves within the piston housing.
Typically, valves are employed to regulate the flow of fluid into and out of the pressure chamber. For instance, an inlet check valve typically includes a ball-check valve that opens to permit fluid flow in to the pressure chamber when the pressure inside the chamber has decreased as a result of outward movement of the piston. When the pressure in the pressure chamber is high, the inlet check valve closes, preventing fluid from exiting the pressure chamber, which in turn prevents the piston chamber from contracting, which in turn prevents the piston from retracting, achieving a so-called "no-return" function.
In some tensioners, a pressure relief valve allows the tensioner to retract in response to large increases in chain tension. The pressure relief valve typically includes a spring biased check valve. This valve opens when the pressure in the pressure chamber becomes high. The opening of the pressure relief valve allows fluid to exit the pressure chamber, which allows the pressure chamber to contract, thus allowing retraction of the piston.
In operation, the tensioner spring and hydraulic fluid urge the piston outwards, balanced against the inward force of the chain. As the tension in the chain increases, the chain exerts a force on the piston in the direction of piston retraction. As the piston is forced in the retraction direction, the fluid pressure in the pressure chamber increases, but the inlet check valve prevents the fluid from exiting the pressure chamber. If the pressure increases to a predetermined level, the pressure relief valve opens, allowing the fluid to exit the pressure chamber.
If, due to chain wear or other factors, the tension in the chain reduces so that the force of the chain on the piston no longer balances the combined force of the hydraulic pressure and the tensioner spring, then the piston will extend toward the chain, thereby tensioning the chain. As the piston extends toward the chain, the inlet valve opens, allowing hydraulic fluid from the external source of fluid to fill the pressure chamber.
A number of challenges exist in the design of hydraulic tensioners, including high cost and difficulty of manufacture and assembly. Traditionally, hydraulic tensioners have been constructed of cast iron housing bodies with turned and centerless ground pistons. This type of construction is expensive and difficult to manufacture. A need exists for a lower cost hydraulic tensioner which is easier to manufacture and assemble.
One example of a tensioner design directed to reduced cost is described in Ojima et al., U.S. Pat. No. 5,037,357. Ojima et al. disclose a spring loaded tensioner including a body having a bearing surface, a first spring seated against the bearing surface and biasing a piston in a protruding direction. A second spring functions as a damper allowing the piston to retract in response to increasing tension in the belt or chain. The body may be made of sheet metal, allowing for low cost manufacturing. The disadvantages of this design include the reliance on springs to provide the "no return" and pressure relief functions. As a result, this design does not provide the advantages in performance provided by a hydraulic tensioner.
The present invention is directed to a lower cost hydraulic tensioner. A housing body has a bore, and a bore cup received in the bore. The bore cup may be deep drawn of a suitable metal. A piston is slidably received in the bore cup, forming a pressurized fluid chamber with the inside of the bore cup. The piston may also be constructed of drawn metal. Preferably, the fluid chamber is connected to the external source of fluid by a single passage. A valve system is assembled within a valve housing which is positioned within the piston. The valve system performs the inlet check function. In one embodiment, the valve system includes an integral inlet and pressure relief valve which performs both the inlet check function and the pressure relief function.
Because the pressure chamber is formed with the bore cup, rather than the housing body as in conventional tensioners, the housing body of the present invention can be constructed of materials, such as aluminum or plastic, which are less expensive than the cast iron which is employed by conventional tensioners. In addition, the positioning of the valve system within the bore cup eliminates the need to provide a valve system within the housing body. Thus, the positioning of the valve system within the bore also reduces the cost of the tensioner.
Furthermore, the design, employing a single passage connecting the pressure chamber with the external source of fluid, in contrast to a design having two or more passages connecting to the fluid chamber, also simplifies the design of the housing body, allowing for a lower cost hydraulic tensioner. In operation, the single passage design also reduces the amount of pressure fluid lost to the system, resulting in a more efficient and less costly tensioner system.
In some embodiments, the inlet check valve assembly employs the aperture in the bore cup as a valve seat. This design provides for a lower cost valve assembly compared to designs employing a separate member as a valve seat.
Accordingly, it is an object of the present invention to provide a hydraulic tensioner capable of improved response to fluctuations in chain tension. Another object of this invention is to provide a hydraulic tensioner for which the cost of manufacture is lower than the cost of conventional hydraulic tensioners. Another object of this invention is to provide a hydraulic tensioner having a housing body constructed of an inexpensive material. A further object of the invention is to provide a hydraulic tensioner having a bore cup, piston and/or a valve housing constructed of drawn metal. Still another object of this invention is to provide a hydraulic tensioner allowing for ease of manufacture and assembly.


A system stores a plurality of data models, each data model being configured to sort datasets based on a set of criteria unique to the data model. The system further identifies a plurality of content streams on a plurality of content streaming platforms. The system then executes each data model of the plurality of data models on each content stream of the plurality of content streams to generate a labeled content file of each content stream of the plurality of content streams.

The management and understanding of large amounts of structured and unstructured content and data has become increasingly complex as data creation and acquisition continues to be rampant in the information technology fields. Machine learning models can be developed and trained to extract meaning from data such that usefulness from large scale data acquisition may be realized.

Real-time content data processing using robust data models


The invention concerns a method of inserting a watermark in an image comprising at least three components, the method comprises the steps of decomposing at least one component of the image into detail sub-bands in various directions and comprising coefficients, each coefficient being characterized by its position in the detail sub-band to which it belongs and its amplitude, of determining, for each position, information representing local amplitude variations from the amplitudes of the coefficients at this position in the various detail sub-bands and the coefficients close to this position in the various detail sub-bands, of determining a watermarking strength at each position from the information representing determined local amplitude variations in the said position and inserting a watermark composed of a plurality of binary information in the image, inserting each item of binary information at a position on the image according to the watermarking strength determined for a position corresponding to the position at which the binary information is inserted.

The present invention concerns a method and device for watermarking an image comprising at least three components.
It also concerns a method and device for detecting a signature inserted in an image comprising at least three components.
The invention is situated in the field of watermarking, images comprising several components such as for example color images. These watermarking techniques can for example be used for protecting copyright on a digital image.
The watermark inserted in an image must amongst other things be robust to the various manipulations of the image. Such manipulations are for example compression thereof.
The watermark inserted in an image must also be imperceptible in order to preserve the quality of the image.
In the French patent application filed under the number 0304592 by the present applicant and not yet published there are described a method and device for watermarking a colored image by vector approximation, taking account of its color dimension.

Method and device for watermarking an image


A mobile apparatus for turning, and otherwise agitating, compost materials in an elongated windrow, is described. The invention includes a chute structure, that can be moved into, and along, the windrow. A toothed drum, at the leading end of the chute structure, penetrates the compost material, and throws it upwardly, and rearwardly, onto an inclined conveyor. The conveyor transports the materials upwardly to a discharge point, located at the trailing end of the chute structure. Gravitational forces cause the materials to intermittently fall back toward the drum, thereby churning and mixing the materials. Pressurized air is continually sprayed onto the materials on the conveyor, in order to aerate the materials while they are being churned and transported.

The present invention relates to a mobile apparatus for turning, and otherwise agitating and aerating, compost materials, in a compost windrow. The apparatus has particular utility in long, relatively massive compost windrows, measuring, e.g., three hundred feet long, sixteen feet wide and eight feet high.
It has become a practice in the composting of biodegradable materials on a mass production basis, to arrange the compost materials in long stacks, or windrows, having humped semi-cylindrical configurations. Periodically, e.g., twice a week, it is necessary to recombine, or stir up the compost materials, in order to quicken, or facilitate, the oxidation and biodegradation process, throughout the windrow. The periodic stirring, or mixing, of the compost materials, redistributes the microbiological agents, and also breaks up the partially decomposed materials into smaller particles, that are then more readily oxidized, and biologically broken down. Another function of the periodic mixing operation, is to aerate the mass of compost materials buried within the interior of the windrow, i.e., beneath the windrow outer surface. Aeration is believed essential to reasonably short biological degradation action.
Conventional apparatus for turning or remixing the compost materials in an elongated windrow, often involves a tunnel-like apparatus that embraces the windrow and moves along the windrow length. A power-driven drum, or rotary rake mechanism, within the tunnel, churns up the compost materials, as the apparatus moves along the length of the windrow. In some cases, the rotary rake merely moves through the compost materials to spread the materials apart.
Another conventional windrow turning apparatus has a powered inclined endless web mechanism on its front end for penetrating the end face of the windrow, as the apparatus moves in a lengthwise direction along the windrow. The endless web has projecting teeth, that exert a shredding action on the compost materials, as the apparatus moves forward into the compost pile, or windrow. In the process, the motion of the web shoots the compost material upwardly, and forwardly, in front of the apparatus.
None of the conventional machines, with which we are familiar, includes the critical aeration mechanisms of the present invention. Aeration is achieved only to a very limited extent, by the churning movement of the compost materials upwardly out of the compost bed. As each particle becomes airborne, it is to a certain extent aerated, at least on its surface.
We believe that there is a clear need for a low cost compost-turning apparatus, that will also produce a greater degree of forced aeration, while at the same time achieving a satisfactory mixing and shredding action. In regard to the cost factor, it is believed that large scale composting could be made more attractive, if machines could be developed that would utilize conventional farm tractors for moving the apparatus and powering the rotary components on the apparatus. One object of the present invention is to provide just such an apparatus, i.e., a compost apparatus that can be towed and operated, in conjunction with a conventional tractor.

Mobile apparatus for turning and aerating compost materials in a compost windrow