The bearing pads of a hydrodynamic tilting pad thrust bearing are cut from a ring and arranged in a circle within a retainer for bearing the load of a collar fastened to a rotating shaft. The leading and trailing edges of respective adjacent pads contain open edge grooves which together form a pocket for receiving and dispensing lubricating and cooling oil under controlled conditions. Semicircular grooves in the edges of the adjacent pads together form generally circular ducts through which the oil is conducted to the pockets.

The disclosure herein relates to thrust bearing assemblies that typically comprise a retainer ring encompassing a plurality of thrust bearing pads arranged in circumferential spaced relationship around a shaft axis. A shaft that is to be axially supported for rotation usually has a radially extending collar providing a bearing surface that interfaces with the circular array of thrust pads which are bathed in a fluid, such as oil, which lubricates and cools the bearings. The thrust pads are customarily supported on a circular array of overlapping pivotal upper and lower leveling links that transmit forces between each other to equalize the load on the thrust pads. The pads are free to tilt to a limited extent so as to develop a wedge-shaped film of lubricant that supports the load. To equalize the load among the pads, the leveling links lower the overloaded thrust pad and raise the underloaded thrust pads. Since the leveling links are in contact, any unbalanced forces are transmitted through the leveling links until equilibrium is reached. The retainer or base through which the load on the shaft is transmitted to ground or the machine frame is in the form of an annular channel having a closed bottom and an open top and in which the leveling links and tilting bearing pads reside.
Whether the shaft is turning about a horizontal axis or a vertical axis, a thrust bearing assembly is encased in a housing through which the oil is forced at relatively low pressure for cooling and lubricating the bearings. Flat bronze floating ring seals are installed on the shaft on each side of the bearing assembly. These ring seals act as a barrier against flow or leakage of cooling oil along the longitudinal surface of the shaft. There is a small clearance between the shaft and the inside of the ring so the shaft can rotate without dragging the seal around with it. A design that permits getting rid of these floating ring seals would be desirable because, they not only add to manufacturing costs, but they do produce some non-useful energy dissipation because of the shear forces that are developed in the lubricant between rotating and stationary parts.
Conventional hydrodynamic thrust bearings used in high speed machinery require circulating a large quantity of lubricating oil through the bearing housing at low pressure. The practical effect is that high capacity circulating pumps are necessary which increases system costs. In addition, if lubricating oil flow rate can be reduced, the size of other elements in the cooling system can be reduced such as the oil sump, heat exchangers, valves, filters and other fittings.
The thrust pads whose leading edges must tilt away from the load transmitting collar on the shaft in order to form a wedge of lubricating oil between the collar and pads are usually cut from a solid ring of bearing material. More specifically, the ring comprises a steel annulus on one surface of which there is a coating of babbitt or other low friction material. The annulus or ring is then milled or sawed along radial lines to divide it into a number of sectors or generally pie-shaped segments. In conventional tilting pad bearing assemblies which use high flow lubricating and cooling systems, a substantial amount of space is allowed between the leading edge of one pad and the trailing edge of the next preceding pad all the way around the circular array of pads in the retainer. The leading and trailing edges of the pads are machined to fairly high accuracy after they are sawed since they must fit in the annular channel of the retainer with enough clearance on their radially inward and outward ends to permit a slight amount of tilting during operation without jamming up against the walls of the retainer. No provision is made in conventional bearings for radial inward or outward adjustment of the bearing pads. The gaps between pads defined by the trailing edge of one pad and the leading edge of the adjacent pad must be rather large because these gaps are major passageways for the lubricating and cooling fluid flow. Under these conditions, there is no way to control the amount of leakage flow at the gap between pads for bearings with low surface frictional drag properties. This can be disadvantageous because it prevents conventional bearings from performing properly at low oil flow. Expired Lakey U.S. Pat. No. 2,507,021 appears on first impression to have a feature which might possibly solve some of the problems in conventional bearings which are discussed above. The feature of interest is a radially extending groove or channel which is formed in the load bearing face of the pads, particularly inwardly from and in parallelism with the leading edge of the pads. The groove, of course, is open at its top and has closed ends. A tube feeds oil into the bottom of the groove so it fills the groove with oil. The reason for supplying oil to the pads in the region of the groove is to compensate for the amount of oil that is centrifuged radially outwardly of the pad surfaces by rotation of the interfacing load transmitting surface on the collar. The oil is fed through a duct under each pad which duct is connected to the input port or bottom hole in the groove by means of a connecting tube which has spherical outside ends so that the pads can tilt without being blocked by the tube. Because the radially extending groove is set inwardly from a radially extending leading edge of the pad there is no provision for controlling the amount of fluid that flows into the gap between pads as is the case with the invention described herein.


A method for controlling and removing dust and other fine particles in a material comprising i) electrostatically charging carrier particles in powder form to give the carrier particles a minimum charge to mass ratio of +/xe2x88x921xc3x9710xe2x88x924 C/kg, ii) delivering the electrostatical charged carrier particles to the material, whereby the dust and other fine particles in the material agglomerate with the charged carrier particles and iii) removing the resultant agglomerates from the material (for example by vacuuming or brushing). An apparatus for delivering electrostatically charged particles to a material, the apparatus comprising a) a container, in which particles to be electrostatically charged are stoned and b) means for delivering the particles from the container to the carpet of fabric material, the delivery means comprising i) a tube or pipe for delivering the carrier particles to the carpet or fine fabric material; and ii) means for expelling particles at high velocity from the container to the material; the tube or pipe being made of such a material that, when carrier particles are passed down the de tube at high velocity, a minimum charge to mass ratio of +/xe2x88x921xc3x9710xe2x88x924C/kg is imparted to the particles by the frictional contact of the particles on the inside of the tube or pipe.

The present invention relates to a method for removing dust and particles, which may include allergens, found in carpet and fine fabric material as well as to an apparatus for delivering electrostatically charged particles to the said material.
The invention, we believe functions, by the dust and fine particles agglomerating with electrostatically charged particles, after which the resulting agglomerates can be removed, for example by vacuuming.
It is well known to remove dust and fine particles from carpets by vacuuming. Although most commercial vacuum cleaners will remove some dust and fine particles from carpets, there will always be some fine dust particles left in the carpet that due to their size cannot be sucked into the vacuum cleaner. It is normally the very fine particles which are the most difficult to remove. Particles below 10 xcexcm in diameter, commonly called PM10s, which are lodged deep in the carpet pile near the backing, are always difficult to remove efficiently. It is these particles that are considered to be most hazardous in terms of health implications.
In addition even those PM10s which are removed by the vacuum cleaner may well not be retained in the vacuum cleaner filter and may therefore subsequently be released into the atmosphere through the filtration system of the vacuum cleaner. As a result it is often necessary to have special filter bags to retain the dust and fine particles actually in the vacuum cleaner.
During vacuum cleaning of such materials as carpets, those particles which are not removed have a tendency to be disturbed and thus become airborne. Thus a high level of airborne particles (which may include allergens) may occur. Particles of up to 10 xcexcm in diameter can remain airborne for long periods of time and are small enough to be inhaled into the human respiratory system. In this way, the faeces of the house dust mite (Dermatophagoides pteronyssinus or Dermatophagoides farinae)xe2x80x94now recognised as the most common allergen carrier associated with asthma, enters the respiratory system. These allergens are known as known as the Der p and Der f allergen series. In addition, the feline allergen (Fel d series) can also be transmitted to the respiratory system.
It is an aim of the present invention to provide an improved method and apparatus for controlling and removing dust and other fine particles, especially the Der f and Der p allergens in, for example, a carpet.
It is a further aim of the present invention to provide an improved method of dispensing charged particles to a surface.
According to one aspect of the present invention there is provided a method for controlling and removing dust and other fine particles in a material, such as a carpet or fine fabric material, comprising
i) electrostatically charging carrier particles (for example by tribo-electric charging, induction charging or corona charging) in powder form to give the carrier particles a minimum charge to mass ratio of +/xe2x88x921xc3x9710xe2x88x924 C/kg,
ii) delivering the electrostatically charged carrier particles to the material, whereby the dust and other fine particles in the material agglomerate with the charged carrier particles and
iii) removing the resultant agglomerates from the material.
The agglomerates can be removed from the carpet or other material by a vacuum cleaning process or by a brush. The agglomerates, which are significantly larger than individual dust particles, will be easier to remove by vacuum cleaning, especially where the cleaning process includes mechanical agitation and vacuum suction.
In addition, the agglomerates are less likely to become airborne than the individual dust particles and certainly will not be able to remain airborne for long periods of time. In addition, once the small particles (PM10s) are in a vacuum cleaner as a component of the agglomerates, their escape through the filtration system of the vacuum cleaner will likewise be significantly reduced.
Where the material to be treated is a carpet, the charged carrier particles penetrate right down to the backing of the carpet and attract dust and other fine particles from the depths of the carpet, so that these can also be removed more efficiently.
The carrier particles used in the method of the invention may be electrostatically charged as they are being applied to the carpet or other material. For example, the carrier particles may be stored in the container or a device having a delivery system which is designed so that on delivery an electrostatic charge is imparted, eg by tribo-electric charging, to the particles.
In such an apparatus the carrier particles will become charged as they are expelled through the delivery system onto the carpet or other material.
Alternatively, the carrier particles may be charged and stored in a container before they are applied to the carpet or other material. A process for the preparation of electrostatically charged particles of a high resistivity is described in European Patent Application No. 95921916.3. The already charged particles are then delivered from the container and applied directly to the carpet or other material.
The electrostatically charged carrier particles are preferably powder particles formed from compounds selected from celite, maize, cyclodextrin, polyvinylpyrrolidone, polyester, nylon, calcite treated with oils, polyvinyl chloride (PVC), polytetra fluoroethylene, polystyrene, polycarbonate, polyimides, xe2x80x9cimmobilised tannic acidxe2x80x9d (as defined below) and wax materials (such as a synthetic paraffin wax or a natural wax, for example Carnauba wax).
By the term xe2x80x9cImmobilised tannic acidxe2x80x9d as used herein is meant tannic acid immobilized on polyvinylpyrrolidone beads. xe2x80x9cImmobilised Tannic Acidxe2x80x9d is prepared as follows:
100 mg of tannic acid dissolved in water, 50 mg of Polyclar 10 (ISP, Guildford Sumg) polyvinylpyrrolidone beads were added and stirred for one hour. The beads were filtered from the solution and washed with a few mls of iced water until no colour was seen in the washings. They were then dried in an oven at 50xc2x0 C.
The minimum level of charging required on the carrier particles is such as to provide a charge to mass ratio of xc2x11xc3x9710xe2x88x924 C/kg, although ratios in excess of xc2x11xc3x9710xe2x88x923 C/kg may be achieved using the charged particle application system hereinafter described with reference to FIGS. 2, 3 and 4 of the accompanying drawings.
The electrostatic charge on the carrier particle may be of positive or negative polarity, or may be a mixture of both when the particles are frictionally charged mixtures of different electrically insulating materials.
The charged particles used in the method of the invention preferably have a diameter in the range of from 10 to 500 xcexcm, more preferably 100 to 300 xcexcm.
In carrying out the method according to the invention, at the same time as (or after) the electrostatically charged carrier particles are applied to the material, the surface of the material is preferably agitated in order to ensure that the dust and small particles agglomerate with the charged carrier particles and are therefore captured. Agitation may be carried out at the same time as the electrostatically charged particles are delivered to the carpet, or as an intermediate agitation step between delivery of the electrostatically charged carrier particles and their final removal, or during the final removal step.
The method of the invention therefore enhances the removal of small particles from the carpet or other material (xe2x80x9cMop-Upxe2x80x9d), restricts the number of particles becoming airborne during the removal of the small particles (xe2x80x9cDamp-Downxe2x80x9d), and increases the capacity of a vacuum cleaner to retain the small particles (xe2x80x9cStay-Putxe2x80x9d).
It has been found that the charging levels on the powder are increased when the velocity of the particles through the charging tube or pipe is increased. Generally the velocity of the particles being passed down the tube or pipe will be in the range of from 10 to 80 m/sec, preferably from 30 to 60 m/sec and more preferably 42 m/sec, in order to achieve the desired charge levels.
The length of the charging tube or pipe and the number and diameter of any apertures formed in the charging tube will also affect the charging levels on the powder. Generally the charging tube or pipe will have a length in the range of from 50 to 500 mm, preferably 100 mm to 300 mm. During the charging of the powder the air pressure in the charging tube is higher, than atmospheric pressure. The number, size and arrangement of any holes formed in the charging tube or pipe will preferably be such that continuous tribo-electric charging can occur without the holes allowing so much air to escape from the holes because of the pressure difference that the loss in air and powder velocity will reduce the level of triboelectric charge. Preferably, therefore, the holes will each have a diameter of less than 5 micrometres, more preferably from 2 to 3 micrometres in diameter. The holes may be of this size since electrical discharge through the holes does not require a large cross-sectional area.
It is possible to increase the amount of turbulence of the particles during charging and hence the contact of the particles with the surface of the tube or pipe by arranging for the particles to travel along a tortuous path. This may be achieved, for example, by arranging the tube or pipe in a non-linear fashion for example as a coil. When the tube or pipe is arranged in this manner, longer tubes or pipes are preferably used in order to maximise the contact of the powder with the surface thereof. For example tubes or pipes of up to 300 mm in length may be used.
An additional aspect of the present invention is that the powder may comprise a mixture of at least two different powdered materials which, on charging in the manner as previously described, will accept charges of opposite polarity. This system may be termed a bipolar system. The charging tube or pipe for a bipolar system does not require any discharge holes. The reason for this is that in a bipolar charged system that is balanced there should not be any net build up of charge on the inner surface of the tube or pipe which requires to be discharged. If the bipolar system is unbalanced and a net charge of one polarity builds up on the inner surface of the tube or pipe, this will act to dynamically limit and equalise the imbalance by providing extra charge for one powder and inhibiting charge transfer from the other powder.
Accordingly, in a further aspect the present invention provides a method of dispensing charged particles to a surface from a container which contains uncharged particles, which method comprises the steps of:
entraining the particles in a stream of gas;
directing the stream of gas and entrained particles through a tube or pipe capable of imparting to the particles a minimum charge to mass ratio of +/xe2x88x921xc3x9710xe2x88x924 C/kg, by frictional contact of the particles with the inner surface of the tube or pipe; and directing the stream of gas and entrained charged particles to a surface;
wherein a mixture of particles of at least two different materials is employed, the particles of a first material being capable of assuming, on charging, a charge of a particular polarity and the particles of a second material being capable of assuming, on charging, a charge of the opposite polarity to that of the first particles.
It will be appreciated that use of such a mixture of charged particles has particular advantages in controlling and removing dust and other fine particles in a material, for example, a carpet. This is because, in practice, the dust and other fine particles in the material will themselves be charged and will be attracted to a charged particle of opposite polarity directed onto the material. This has distinct advantages in both the xe2x80x9cMop-Upxe2x80x9d and xe2x80x9cDamp-Downxe2x80x9d phases of removal of small particles from the material.
In a still further aspect the present invention provides a method of dispensing charged particles to a surface from a container which contains uncharged particles,
which method comprises the steps of entraining the particles in a stream of gas;
directing the stream of gas and entrained particles through a tube or pipe capable of imparting to the particles a minimum charge to mass ratio of +/xe2x88x921xc3x9710xe2x88x924 C/kg, by frictional contact of the particles with the inner surface of the tube or pipe; and directing the stream of gas and entrained charged particles to a surface;
wherein the tube or pipe includes a plurality of holes therein which are dimensioned so as to allow for electrical discharge through the holes, without allowing gas flow through the holes to the extent that the velocity of the stream of gas which entrains the particles is substantially reduced.
Such methods of directing charged particles to a surface represent a significant improvement over the known art for particle delivery. In particular, the charged particles, especially those of higher charge, now experience a much higher rate of dispersion and have an increased ability to stick to surfaces to which they are delivered, including glass, ceramics, plastics, metals, skin and hair. In addition to this, the charged particles have an ability to stick to those parts of the surface to which they are directed which are not directly exposed to the charged particles and other inaccessible places, for example, around and behind cylinders such as glasses and bottles, behind door handles and the like and in-between and around toes and fingers. As such, the charged particles so delivered stick evenly on the surface avoiding build-up and uneven distribution of the charged particles on the surface. This has particular advantages when it is desired that a substantially even distribution of charged particle is required in a particular application, for example, delivery to a toilet bowl or rubbish bin.
It will be appreciated that this has particular advantages in the delivery of an active ingredient to a surface as required, for example, in the treatment of a fungal infection such as athlete""s foot. In such an instance, the active ingredient may either be included in the charged particles themselves, or the active ingredient may itself be a charged particle.
In so far as the above outlined advantages are concerned, it is preferred that a charged particle mixture of a single polarity is used. Whilst not wishing to be bound by theory, it is believed that the repulsion between like charged particles aids in both the even distribution of the charged particles on the surface as well as the unique dispersion of the charged particles.
According to another aspect of the invention there is provided an apparatus for delivering electrostatically charged particles to a material, such as carpet or fabric material, the apparatus comprising
a) a container, in which particles to be electrostatically charged are stored and
b) means for delivering the particles from the container to the carpet or fabric material, the delivery means comprising
i) a tube or pipe for delivering the carrier particles to the carpet or fabric material; and
ii) means for expelling particles, preferably at high velocity (eq a velocity of 1 to 100 m/sec), from the container to the material;
the tube or pipe being made of such a material that, when carrier particles are passed down the delivery tube at high velocity, a minimum charge to mass ratio of +/xe2x88x921xc3x9710xe2x88x924 C/kg (preferably from +/xe2x88x921xc3x9710xe2x88x924 to +/xe2x88x921xc3x9710xe2x88x923 C/kg) is imparted to the particles by the frictional contact of the particles on the inside of the tube or pipe.
The tube of the apparatus can preferably be made from plastics material, for example
perforated polyethylene
unperforated and preferably perforated nylon and, unperforated and preferably perforated polytetra-fluoroethylene (PTFE) commercially available as Teflon.
Without wishing to be bound by theory, we believe that the preferred tube used is depend ant on the carrier particles to be used. For example if the particles used are towards the positive end of the series, the preferred tube is made of a material towards the negative end of the tribo-electric series and if the particles are towards the negative end of the tribo-electric series, the material of the tube is towards the positive end of the series.
Preferably when the tube is made of perforated polyethylene, the preferred carrier particles are xe2x80x9cimmobilised tannic acidxe2x80x9d as defined above.
Preferably when the tube is made of perforated and unperforated PVC, the preferred carrier particles are selected from nylon, polyvinylpyrrolidone (PVPP), xe2x80x9cimmobilised tannic acidxe2x80x9d, maize, calcite treated with oils and celite.
Preferably when the tube is made of perforated and unperforated nylon, the preferred carrier particles are selected from polyester, PVPP, xe2x80x9cimmobilised tannic acidxe2x80x9d, cyclodextrin, and calcite, untreated or treated with oils.
Preferably when the tube is made of PTFE, the preferred carrier particles are selected from nylon, PVPP, xe2x80x9cimmobilised tannic acidxe2x80x9d, cyclodextrin and calcite, untreated or treated with oils.
Preferably the delivery means include means for expelling particles at high velocity from the container to the material. Such means may be driven by compressed air (i.e. compressor systems such as xe2x80x9cpufferxe2x80x9d packs or by the use of pressurised gases such as in aerosols). The carrier particles may also be applied to the material by a feed tube that works off the suction effect of a vacuum cleaner, such as a VAX wet and dry vacuum cleaner.
In a yet further aspect the present invention provides apparatus for dispensing charged particles, which apparatus comprises:
a container for housing the particles to be dispensed;
a tube or pipe capable, in use, of imparting to the particles a minimum charge to mass ratio of +/xe2x88x921xc3x9710xe2x88x924 C/kg by frictional contact of the particles with the inner surface of the tube or pipe; and
means for entraining the particles in a stream of gas and directing the stream into the tube or pipe;
wherein the tube or pipe is arranged within the container in order to facilitate frictional charging of the particles by contact, in use, of the particles with the inner surface of the tube

Method for controlling and removing dust and other particles from a material


A method for aqueous phase nucleic acid isolation from a sample, comprising a step of nucleic acid adsorption on a particulate substrate, is disclosed. The method comprises an adsorption reagent preparation step (a) that includes a sol consisting of a aqueous continuous phase and a dispersed particulate substrate phase including a functionalized particulate polymer prepared by polymerizing (1) a first water-soluble acrylamide or acrylamide derivative monomer, (2) at least one cross-linking agent and (3) at least one second water-soluble, cationic and functional monomer, said polymer having a predetermined lower critical solubility temperature (LCST) of 25-45xc2x0 C.; a contact step (b) wherein the adsorption reagent is contacted with the sample containing the nucleic acid; an adsorption step (c) wherein, to carry out the contact step (b), at least one parameter is selected for the reaction medium, said parameters being a pH no higher than 7, an ionic strength no higher than 10xe2x88x922 M, and a temperature lower than the polymer LCST; a separation step (d) wherein the dispersed phase is separated from the continuous phase, optionally after it has been observed that adsorption has occurred; and a desorption step (e) wherein the nucleic acid is desorbed from the particulate substrate by increasing the ionic strength until an ionic strength higher than 10xe2x88x922 M is achieved.

The present invention belongs to the field of purification of nucleic acids, in aqueous medium.
A process is known according to the document WO-A-95/04140 for purifying, in aqueous medium, nucleic acids present in a sample, according to which said sample is brought into contact with a particulate system consisting of silica beads, in the presence of a chaotropic substance, and then the nucleic acids attached to the beads are separated from the final aqueous solution.
In accordance with the document F. Meunier et al., Polymers for Advanced Technologies, Volume 6, pp. 489-496, (1995), the preparation of a polymer called PNIPAM, by polymerization of (1) N-isopropylacrylamide, (2) N,N-methylenebisacrylamide and (3) 2-aminoethylmethacrylate chloride, in the presence of a polymerization initiator, is described. The behavior of this surface-functionalized polymer can make it particularly suited to a covalent attachment of biological molecules.
The document EP-A-0 161 881 teaches that a heat-sensitive polymer such as the polymers obtained by copolymerization of monomers of N-alkyl- or of N-alkylene-acrylamide or methacrylamide and of monomers of acrylic or methacrylic derivatives, can be used in the isolation of biological material, by virtue of its capacity to change structure as a function of the temperature. It has an open structure at low temperature, which facilitates the attachment of a biological material, and a retracted structure at high temperature, which allows the liberation of the attached biological material. The control of the steps of attachment and liberation of the biological material can therefore be performed by varying the temperature. For a better control, it is possible, in addition, to vary the pH.
The use proposed by this document extends to the isolation of any biological material present in a sample, and in particular nucleic material and protein material, without any specificity.
According to the invention, a process for the selective isolation of a nucleic material present in a sample is provided. Even if the sample is complex and contains a protein material and/or inhibitors of enzymatic reaction, the process of the invention limits or even eliminates any isolation of the protein material and/or of said inhibitors, while promoting the isolation of the nucleic material.
A process for the isolation in aqueous phase, according to the invention, of a nucleic material present in a sample, comprises the following steps:
according to a so-called step (a) for producing the adsorption reagent, an adsorption reagent is available which comprises a sol consisting of an aqueous continuous phase and a discontinuous phase of the particulate support which comprises a functionalized, particulate polymer, said polymer being obtained by polymerization of (1) a first water-soluble monomer of acrylamide or of an acrylamide derivative, (2) at least one cross-linking agent and (3) at least a second cationic and water-soluble functional monomer, said polymer having a predetermined lower critical solubility temperature (LCST) which is between 25 and 45xc2x0 C., preferably between 30 and 40xc2x0 C., according to a so-called step (b) for bringing into contact, the adsorption reagent is brought into contact with the sample containing the nucleic material,
according to a so-called adsorption step (c), for the bringing into contact according to (b), at least one and preferably at least two of the following parameters for the reaction medium are chosen:
pH at most equal to 7,
ionic strength at most equal to 10xe2x88x922 M,
temperature less than the LCST of the polymer,
according to a so-called separation step (d), after having optionally observed that the adsorption has taken place, the discontinuous phase and in particular that having adsorbed the nucleic material are separated from the continuous phase,
according to a so-called desorption step (e), the nucleic material is dissociated, by desorption, from the particulate support by increasing the ionic strength up to an ionic strength greater than 10xe2x88x922 M.
Advantageously, for the desorption step (e), at least one of the parameters selected from the pH and the temperature is in addition varied as follows:
increase in the pH up to a pH greater than 7,
increase in the temperature up to a temperature greater than the LCST of the polymer.
The invention also relates to a process for the isolation, in aqueous phase, of a nucleic material present in a sample, comprising a step of adsorption of said nucleic material, onto a particulate support, allowing a use as such of the nucleic material adsorbed onto the particulate support, in a subsequent analytical step. This process comprises the following steps:
according to a so-called step (a) for producing the adsorption reagent, an adsorption reagent is available which comprises a sol consisting of an aqueous continuous phase and a discontinuous phase of the particulate support which comprises a functionalized, particulate polymer, said polymer being obtained by polymerization of (1) a first water-soluble monomer of acrylamide or of an acrylamide derivative, (2) at least one cross-linking agent and (3) at least a second cationic and water-soluble functional monomer, and said polymer having a predetermined lower critical solubility temperature (LCST) which is between 25 and 45xc2x0 C.,
according to a so-called step (b) for bringing into contact, the adsorption reagent is brought into contact with the sample containing the nucleic material,
according to a so-called adsorption step (c), for the bringing into contact according to (b), an ionic strength at most equal to 10xe2x88x922 M is selected for the reaction medium,
according to a so-called separation step (d), after having optionally observed that the adsorption has taken place, the discontinuous phase is separated from the continuous phase, according to which process the desorption step is optional.
In accordance with a preferred embodiment of the latter process, according to the adsorption step (c), for the bringing into contact according to (b), at least one of the following parameters is in addition selected for the reaction medium:
pH at most equal to 7,
temperature less than the LCST of the polymer.
Of course, this process may comprise, after the separation step (d), a so-called desorption step according to which the nucleic material is dissociated, by desorption, from the particulate support by varying at least one of the parameters selected from the ionic strength, the pH and the temperature, as follows,
increase in the ionic strength up to an ionic strength greater than 10-2 M
increase in the pH up to a pH greater than 7,
increase in the temperature up to a temperature greater than the LCST of the polymer.
At least the ionic strength is advantageously varied.
The processes defined above according to the invention will be preferably carried out according to two variants related to step (a).
According to a first variant which will be illustrated in the examples, the particulate support consists of said particulate polymer, and in this case, the cross-linking agent(s) (2) are water-soluble.
According to a second variant, the particulate support comprises, in addition, an organic or inorganic core, completely or partially coated with said particulate polymer, said core not modifying the adsorption properties of the polymer in relation to said nucleic material. The core or core portion then fulfills the function of the cross-linking agent (2), it being possible to provide another cross-linking agent of the water-soluble cross-linking agent type. By way of example, the core may be a polystyrene core, and/or comprise a magnetic compound.
According to a specific and preferred embodiment of these processes, at least one probe and/or one primer capable of specifically hybridizing to the nucleic material before or after step (b) is added to the sample before step (b), or to the reaction medium after step (b), and in particular after step (c) or step (d).
In another specific embodiment, the nucleic material consists of a probe or a primer, and according to (b) and (c), the adsorption reagent is brought into contact with said nucleic material in order to obtain a hybridization reagent, and then according to (bxe2x80x2), after having optionally observed that the adsorption has taken place, and separated the hybridization reagent from the reaction medium, said hybridization reagent is brought into contact with a medium containing at least one nucleic acid or nucleic acid fragment, under suitable conditions for the hybridization or the extension of the primer.
The particulate polymer is advantageously obtained by free radical polymerization in the presence of a cationic or neutral, and water-soluble, polymerization initiator.
The first monomer (1) is preferably selected from the N-alkylacrylamides and the N,N-dialkylacrylamides, and more particularly from N-isopropylacrylamide, N-ethylmethacrylamide, N-n-propylacrylamide, N-n-propylmethacrylamide, N-isopropylmethacrylamide, N-cyclopropylacrylamide, N,N-diethylacrylamide, N-methyl-N-isopropylacrylamide, N-methyl-N-n-propylacrylamide, the first monomer being preferably N-isopropylacrylamide (NIPAM).
The second functional monomer(s) (3) are preferably selected from the acrylic and methacrylic derivatives, 2-aminoethylmethacrylate chloride (AEM), the N-vinylpyridine derivatives, the trialkylammonium derivatives and the isothiouronium chloride derivatives.
Advantageously, the water-soluble cross-linking agent (2) is selected from N,N-methylenebisacrylamide (MBA), ethylene glycol dimethacrylate, and the polymerization initiator is 2,2xe2x80x2-azobisamidinopropane chloride (V50).
The separation step (d) is preferably carried out according to a technique selected from centrifugation, filtration, precipitation, sedimentation and the application of a magnetic field.
Before the separation step (d), it can be optionally observed that the adsorption reaction has occurred. By way of example, HPLC or capillary electrophoresis techniques may be used.
Before disclosing the invention in greater detail, some terms used in the present description and in the claims are defined below:
isolation of a nucleic material according to the invention is understood to mean the separation, detection of this material, the enrichment of a fraction with nucleic material, according to a specific or a specific method of isolation, in a qualitative and/or quantitative manner.
A nucleic material according to the invention is a nucleic acid, a nucleic acid fragment, a mixture of nucleic acids and/or of nucleic acid fragments, or a fraction of nucleic acids and/or of fragments of nucleic acids. Nucleic acid is understood to mean any nucleic acid, in a free form or optionally combined with proteins, regardless of its cellular, bacterial or viral origin or the like. It is either a deoxyribonucleic acid or ribonucleic acid, consisting of a stretch of natural nucleotides whose constituent elements are a sugar, a phosphate group and a nitrogen base selected from adenine, guanine, uracil, cytosine, thymine and/or of nucleotides modified in at least one of the three constituent elements; by way of example, the modification may take place at the level of the bases, generating modified bases, such as inosine, 5-methyldeoxycytidine, deoxyuridine, 5-dimethylaminodeoxyuridine, 2,6-diaminopurine, 5-bromodeoxyuridine, and such as bases modified by a tracer detectable directly or indirectly by techniques known to persons skilled in the art, by way of example bases modified by biotin; at the level of the sugar, namely the replacement of at least one deoxyribose by a polyamide; and/or at the level of the phosphate group, for example its replacement by esters selected in particular from the diphosphate, alkyl- and arylphosphonate and alkyl- and arylphosphorothioate esters. The nucleic acid according to the invention is completely or partially single-stranded and/or double-stranded, in particular it may consist of a probe-nucleic acid, probe-nucleic acid fragment, primer-nucleic acid or primer-nucleic acid fragment duplex; the duplex may be a homoduplex or a heteroduplex.
The invention is of course applied to the isolation of fragments of nucleic acids as defined above, or oligonucleotides (ODN), of variable sizes.
The nucleic material may be of natural origin, and/or obtained by genetic recombination and/or by chemical synthesis; by way of example, it may consist of a probe or a primer.
The present invention is applied to the aspecific isolation of a fraction of nucleic acids and/or of fragments of nucleic acids, which is contained in a sample, but also to the specific isolation of a nucleic acid or a nucleic acid fragment, or of a mixture of nucleic acids or of fragments of nucleic acids, which are present in a sample.
A sample as understood according to the invention comprises any sample capable of containing a nucleic material, in particular a biological sample such as that obtained from a biological fluid, a sample of food origin. The sample consists wholly or partly of a sample, in particular it may consist of an aliquot, a dilution. The sample may or may not have been subjected to a preliminary treatment, in particular of purification or lysis in order to facilitate the liberation of the nucleic acids.
The LCST of a polymer such as that which is the subject of the present invention is in particular defined and measured by techniques described in the following documents: Hiroshi Inomata et al., Macromolecules 1994, 27, 6459-6464.
A probe is a nucleotide fragment possessing a hybridization specificity under determined conditions for forming a hybridization complex with a nucleotide fragment. A probe used within the framework of the present invention will be preferably a capture probe, without nevertheless excluding the other types of probes from this context.
Primerr according to the invention is understood to mean a probe possessing a hybridization specificity under determined conditions for the initiation of an enzymatic polymerization, for example in an amplification technique such as PCR (Polymerase Chain Reaction), the so-called NASBA technique (xe2x80x9cNucleic Acid Sequence-Based Amplificationxe2x80x9d) or alternatively the so-called TMA technique (Transcription Mediated Amplification), in an extension process, such as sequencing, in a reverse transcription method or the like.
Acrylamide derivative according to the invention is understood to mean a polymerizable monomer corresponding to the formula R0xe2x80x94CHxe2x95x90C(R1)xe2x80x94CONR2R3, in which R0, R1, R2 and R3 represent a group selected independently from hydrogen, aliphatic or cyclic, linear or branched lower hydrocarbon groups, nitrogen-containing heterocyclic groups such as imidazole.
The adsorption of nucleic material as understood according to the present invention is defined as follows: a nucleic material is adsorbed onto a particulate support if, after a period of contact between said material and said support, at least one of the groups belonging to the constituent components of the nucleic material is attached to the surface of the support; the adsorption results from ionic interactions and/or hydrogen bonds, and possibly hydrophobic interactions, excluding any covalent bond, between the material and the support.
Finally, functionalized polymer is understood to mean a polymer having at least one interface carrying functional groups capable of generating with groups of the constituent components of the nucleic material any one of the interactions and/or bonds involved in the adsorption phenomenon. Preferably, these functional groups are selected from NH3+; NH4+; NR3+ or R represents an aliphatic or cyclic, saturated or unsaturated hydrocarbon group, it being possible for NR3+ to represent the pyridinium group; and the isothiouronium group.


In one example, a dual-axis hinge assembly for an electronic device is disclosed, which may include a casing defining a pair of slots and an elastic member disposed in the casing. The elastic member may include mounting features at opposite ends. The dual-axis hinge assembly may include a pair of shafts received through a respective one of the mounting features and the slots, and engaged with display housing and a main housing of the electronic device to pivotably connect the display housing to the man housing. The elastic member may enable at least one of the shafts to slide along the slots to variably adjust a distance between a pivot axis of the display housing and a pivot axis of the main housing.

Electronic devices such as laptop computers, tablet computers, personal digital assistants (PDAs), flip mobile phones, and the like may include a main housing, a display housing, and a hinge assembly mounted between the main housing and the display housing. For example, the main housing may house a keyboard, a motherboard, and/or other components. The display housing may house a display. The hinge assembly may connect the display housing to the main housing and allow the display housing to rotate relative to the main housing.

Dual-axis hinge assembly for electronic devices

Hewlett-Packard Development Company, L.P.


An airbag system having a crash sensor generates a crash trigger signal when a crash is detected. A passenger detected system detects at least a passenger in the motor vehicle to generate data regarding the passenger. In response to the crash trigger signal, a latest piece of the data regarding the passenger is held in non-volitile memory when the crash is detected to provide the data for the accident analysis.

1. Field of the Invention
This invention relates to a passenger protection apparatus for a motor vehicle with a data recording function.
2. Description of the Prior Art
An airbag unit in which the expansion is controlled in accordance with the detected weight of the passenger is disclosed in Japanese patent application provisional publication No. 11-01153. FIG. 3 shows this prior art airbag system.
The airbag unit 90 includes a gas generation unit with a plurality of inflators 92 which generate gas in response to a controller 70. The controller 70 is supplied with a crash detection signal from a crash sensor 80 and with weight detection signals from weight sensors 71 to 74. When the crash sensor detects a crash, the controller 70 determines the number of inflators to be operated in accordance with the weight determined from the weight detection signals from the weight sensors 71 to 74 and sends the result to the airbag unit 90. This operates the determined number of inflators 92 to expand the airbags 91.
This airbag unit 90 can control the expansion of the airbags to reduce the possibility of airbag side effect.
On the other hand, if a crash accident occurs, data regarding the passenger was not left because of no drive recorder like a flight recorder in an aircraft. That is, it is required to record the data regarding the passenger at the crash accident to analyze the accident.
The aim of the present invention is to provide a superior passenger protection apparatus for a motor vehicle.
According to the present invention, a first aspect of the present invention provides a passenger protection apparatus for a motor vehicle comprising:
an airbag system having a crash sensor and an airbag for generating a crash trigger signal when a crash is detected;
a passenger detection system for detecting said passenger in said motor vehicle to generate data regarding said passenger; and
data holding means having a non-volatile memory for holding said data up to said detected crash in said non-volatile memory in response to said crash trigger signal.
According to the present invention, a second aspect of the present invention provides the passenger protection apparatus based on the first aspect, wherein said passenger detection system having a passenger sensor for detecting said passenger to output a passenger sensor signal and a processing circuit for processing said passenger sensor signal to periodically output said data and an intermediate processing result obtained while said sensor signal is processed, and wherein said data holding means further holds said intermediate results up to said detected crash when said crash is detected.
According to the present invention, a third aspect of the present invention provides the passenger protection apparatus based on the first aspect, wherein said airbag system further comprises an airbag electronic control unit responsive to said crash trigger signal, said airbag being controlled by said airbag electronic control unit, and said passenger detection system comprises a passenger sensor for detecting said passenger to output a passenger sensor signal and a passenger electronic control unit for processing said passenger sensor signal to generate said data.
According to the present invention, a fourth aspect of the present invention provides the passenger protection apparatus based on the third aspect, wherein said airbag electronic control unit includes an acceleration sensor, an airbag control central processing unit, and an airbag communication interface, and said passenger detection electronic control unit includes a memory, a passenger detection central processing unit, and a passenger detection communication interface coupled to said airbag communication interface.
According to the present invention, a fifth aspect of the present invention provides the passenger protection apparatus based on the fourth aspect, wherein said airbag electronic control unit processes the outputs from said crash sensor and said acceleration sensor to generate an operation value indicative of a magnitude of crash and generates said crash trigger signal when said operation value exceeds a light crash level and sends said crash trigger signal only to said passenger detection electronic control unit and supplies said crash trigger signal to said passenger detection electronic control unit and to said airbag when said operation value exceeds a heavy crash level which is higher than said light crash level.
According to the present invention, a sixth aspect of the present invention provides the passenger protection apparatus based on the third aspect, wherein when said passenger detection electronic control unit receives said crash trigger signal, said passenger detection electronic control unit sends said data to said airbag electronic control unit, and when said airbag electronic control unit control said airbag on the basis of the received data from said passenger detection electronic control unit.
According to the present invention, a seventh aspect of the present invention provides the passenger protection apparatus based on the first aspect, wherein said data holding means holds a latest piece of said data in said non-volatile memory when said crash is detected.
According to the present invention, an eighth aspect of the present invention provides the passenger protection apparatus based on the first aspect, wherein said data holding means periodically holds said data in said non-volatile memory and inhibits rewriting said data in said non-volatile memory when said crash is detected.
According to the present invention, a ninth aspect of the present invention provides the passenger protection apparatus based on the first aspect, wherein said data holding means has a temporary memory, periodically holds said data in said temporary memory, and holds the data from said temporary memory in said non-volatile memory in response to said crash trigger signal.
According to the present invention, a tenth aspect of the present invention provides the passenger protection apparatus based on the first aspect, wherein said passenger detection system includes a sensor for detecting a load by said passenger, said data holding means holds said output of said sensor as said data.
According to the present invention, an eleventh aspect of the present invention provides the passenger protection apparatus based on the first aspect, wherein said passenger detection system includes a sensor for detecting a load by said passenger and processes an output of the sensor to have a waveform-shaped signal, said data holding means holds a result from said processed output as said data.
According to the present invention, a twelfth aspect of the present invention provides the passenger protection apparatus based on the first aspect, further comprising a processing circuit for processing a sensor signal from said crash sensor to output processing result, wherein said data holding means further holds said processing result in said non-volatile memory just after said detected crash in response to said crash trigger signal.

Passenger protection apparatus for a motor vehicle


In the double-side pressure-sensitive tapes (A and B) of the first embodiment of the present invention, a first pressure-sensitive adhesive layer (2) comprising a blend of 100 parts by weight of an acrylic or rubber-based pressure-sensitive adhesive composition with from 0.01 to 30 parts by weight of a silicone polymer is formed on one side of a substrate and an acrylic or rubber-based pressure-sensitive adhesive layer is formed as a second pressure-sensitive adhesive layer (3) on the other side. By this, a double-side pressure-sensitive tape in which the pressure-sensitive adhesives, even when being bonded to each other, can thereafter be easily separated is obtained. For the pressure-sensitive tape of the second embodiment of the present invention, a second pressure-sensitive adhesive layer (54) is formed on one inner surface (53a) of both inner surfaces of a tape substrate (53) which are faced to each other and a first pressure-sensitive adhesive layer (55) is formed on the other inner surface (53b), with the second pressure-sensitive adhesive layer and the first pressure-sensitive adhesive layer being formed from pressure-sensitive adhesives having compositions different from each other so as to be separably bonded to each other, and a third pressure-sensitive adhesive layer (56) is formed on a suitable part of the tape substrate (53) other than the both faced surfaces. By this, it becomes possible to improve fixing strength without increasing the area of the tape substrate.

As a double-side pressure-sensitive tape which does not use a release paper (separator), a tape obtained by coating a support on one side with an acrylic pressure-sensitive adhesive and on the other side with a rubber-based pressure-sensitive adhesive is known so far. However, this has drawbacks that adherends to which this tape is applicable are limited, that the property of separating pressure-sensitive adhesives from each other after laminating is unequivocally determined by the modulus of elasticity or the like of the pressure-sensitive adhesives and cannot be varied, and further that since acrylic pressure-sensitive adhesives, for example, have poor storage stability, they are unusable in articles to be used over a long period of time. Further, acrylic pressure-sensitive adhesives and rubber-based pressure-sensitive adhesives differ considerably from each other in properties such as adhesive force, heat resistance, and solvent resistance, and use of the rubber-based pressure-sensitive adhesive is unsuitable in case of bonding with the pressure-sensitive tape, followed by heat treatment, resin processing, or long-term use.
Also, a tape is known as a double-side pressure-sensitive tape free from the necessity of a release paper, which is obtained by coating a support on one side with a pressure-sensitive adhesive prepared by partially crosslinking an acrylic resin having a carboxyl group in a side chain with an isocyanate and on the other side with a pressure-sensitive adhesive prepared by partially crosslinking an acrylic resin having a hydroxyl group in a side chain with a melamine resin (e.g., Unexamined Published Japanese Patent Application 54-108833). However, this tape has a drawback that since the main components of the pressure-sensitive adhesives are limited to acrylic resins, adherends are limited naturally and adhesion to adherends such as polyolefins is poor. Further, use of this tape in sanitary articles or the like has been not preferable since there is a fear that formalin may be emitted because of the crosslinking with a melamine resin.
The first object of the present invention, which has been attained to solve those problems, is to provide a double-side pressure-sensitive tape which is free from the necessity of use of a release paper and which, even when those tapes are laminated with each other, can be easily separated at the interface between pressure-sensitive adhesive layers, by using a pressure-sensitive adhesive layer having a specific composition on one side thereof.
On the other hand, known as a pressure-sensitive tape for use as a fastener tape for fixing the front part of a disposable diaper to the back part thereof is, as shown, for example, in FIG. 20 and FIG. 21, a pressure-sensitive tape 10 produced by double-folding a tape substrate 11 in a manner such that a near-one-end part 11a and a near-other-end part 11b of the substrate become faced to each other, forming a first pressure-sensitive adhesive layer 12 on an inner surface of the near-one-end part 11a in the tape substrate 11, on the other hand, forming a release layer 13 for the first pressure-sensitive adhesive layer 12 on an inner surface of the near-other-end part 11b in the tape substrate 11, and further forming a second pressure-sensitive adhesive layer 14 on an outer surface of the near-other-end part 11b in the tape substrate 11 (Unexamined Published Japanese Utility Model Application 61-94536).
That is, this pressure-sensitive tape 10 has been designed to be used in a manner such that the pressure-sensitive tape 10 is applied beforehand through the second pressure-sensitive adhesive layer 14 to the inner surface of a back part 5A1 in a diaper 5A, the diaper 5A is applied to a baby or infant, the near-one-end part 11a of the tape substrate 11 is peeled from the near-other-end part 11b, and this near-one-end part 11a is bonded to a center tape 5A3 disposed on a front part 5A2 of the diaper 5A, thereby fixing the back part 5A1 of the diaper 5A to the front part 5A2.
According to this pressure-sensitive tape, there is no need to separately dispose a release tape because the tape substrate 11 itself functions as a release tape for the first pressure-sensitive adhesive layer 12 and protects the first pressure-sensitive adhesive layer 12. The above pressure-sensitive tape, therefore, has an advantage that the production process can be simplified and the cost can be reduced.
However, in this pressure-sensitive tape 10, since the inner surface of the near-one-end part 11a in the tape substrate 11 is the only part where the first pressure-sensitive adhesive layer 12 can be formed, the area in which the tape substrate 11 is bonded to the center tape 5A3 is small. Because of this, there has been a problem that the fixing strength to the front part 5A2 of the diaper 5A is so low that the tape substrate 11 shifts as shown by the alternate long and short dash line in FIG. 22 if a tensile force is applied, according to the movement of the baby or infant wearing the diaper 5A, to the tape substrate 11 in a direction along the length of the substrate, and this not only loosens the diaper 5A but also is prone to cause rubefaction or a rash on the skin 5B of the baby or infant because the other end part in the tape substrate 11 contacts with the skin 5B of the baby or infant.
Although it is thought that the above problem may be solved by increasing the area of the first pressure-sensitive adhesive layer 12 by elongating the length size of the tape substrate 11, this results in an increase in the amount of a material used for producing the tape substrate 11 and, as a result, the effect of cost reduction brought about by unnecessity of a release paper is lost.
The second object of the present invention is to provide a pressure-sensitive tape which can markedly improve a fixing strength without increasing the area of the tape substrate.

Double-sided pressure-sensitive adhesive tape, laminated structure comprising the same, and method of use of same


A color filter composition comprises a mixture of a binder and a monomer in a predetermined ratio, a pigment, and a solvent. The predetermined ratio is a ratio of the binder to the monomer and ranges from about 50:50 to about 60:40. The color filter composition further comprises a solid powder having a weight percent in the color filter composition ranging from about 12% to about 18%, wherein the solid powder includes the pigment. The pigment has a weight percent in the solid powder ranging from about 28% to about 38%.

1. Technical Field
The present disclosure relates to a color filter composition, and a method and apparatus for manufacturing a color filter having the color filter composition.
2. Discussion of the Related Art
Devices such as personal and notebook computers, car navigation systems, television sets, etc. may include a liquid crystal display (LCD). The LCD is frequently used because the LCD is lighter and smaller than a display having a cathode-ray tube.
The general structure of an LCD consists of a liquid crystal (LC) layer that is positioned between a pair of panels including field generating electrodes and polarizers. The LC layer is subject to an electric field generated by the electrodes and variations in the field strength change the molecular orientation of the LC layer. For example, upon application of an electric field, the molecules of the LC layer change their orientation and polarize light passing through the LC layer. Appropriately positioned polarized filters block the polarized light, creating dark areas that can represent desired images.
An LCD may include color filters including a red (R) color filter, a green (G) color filter and a blue (B) color filter. Light having a wavelength according to red, green and blue colors may pass through the R, G and B color filters, respectively.
A known color filter composition may include a photo polymerization initiator, a light filtering pigment and a solvent which are spin coated on a substrate to a predetermined thickness to be patterned using a photo process or a photolithography process, thereby forming a conventional color filter. The photo polymerization initiator may be removed using light.
When an LCD apparatus having a large screen size is manufactured using the spin coating process, consumption of components of the color filter and energy is greatly increased and the substrate may be broken by centrifugal force.
A slit coating process also may be used to manufacture an LCD apparatus having the large screen size. In a slit coating process, the color filter composition is discharged through an extended slit to coat a substrate using a slit coater, thereby forming a color filter layer.
However, because the slit is narrow, a portion of the color filter composition may be clogged in the slit or harden in the slit coater. If a portion of the color filter composition adheres to a surface of the slit coater, the color filter layer may be dotted or striped.

Color filter composition, method and apparatus for manufacturing a color filter having the same


Embodiments of the invention relate to graphics rendering in which Z-buffering tests are performed at the front of the rendering pipeline. Particularly, Z-buffering test logic at the front of the rendering pipeline is coupled to a render cache memory, which includes a Z-buffer, such that Z-buffering can be accomplished at the front of the rendering pipeline.

1. Field
Embodiments of the invention relate to the field of Z-buffering. More particularly, embodiments of the invention relate to techniques for improved Z-buffering for graphics rendering in the creation of 3-D graphics.
2. Description of Related Art
Computer graphics systems are frequently used to model a scene having three-dimensional (3-D) objects and then to display them on a two-dimensional display device such as a cathode ray tube. One such system in common use is a polygon-based, object-order graphics system in which 3-D objects in a scene are each represented by a multitude of polygons (or primitives) that approximate the shapes thereof. Depending upon the orientation selected for viewing the scene in two dimensions, many of the primitives representing objects in the scene will be hidden behind other primitives and thus not displayed. Primitives not completely hidden are termed visible and will be displayed, either in full or in part depending upon whether a portion of a given primitive is hidden, in the rendered image on the display device. As the depth complexity (i.e. the number of levels of primitives hidden behind one another) of a scene to be rendered increases, the percentage of all primitives representing the scene that will ultimately be visible by an observer on the display device decreases significantly. Thus, in many cases, most of the primitives for a scene will be hidden.
Conventional computer graphics systems typically have a frame buffer and a Z-buffer. The frame buffer is typically a memory (e.g. Dynamic Random Access Memory (DRAM) or Synchronous Random Access Memory (SRAM)) which holds the digital representation of the color and intensity for each pixel in the image. The frame buffer is also referred to as a video bitmap. The Z-buffer (also referred to as a depth buffer) is a large array of memory with an entry for each pixel in the frame buffer.
One method for determining which primitives will be visible or hidden involves the use of the Z-buffer, and is often termed Z-buffering. The Z-axis in a graphics system reflects the distance from a specific observer's viewpoint. Thus, a larger Z-value represents a greater distance from the viewpoint. Z-buffering involves the comparison of Z-values of points on generated objects to determine which object is closest to the viewpoint and therefore should appear on the two-dimensional display. As a part of processing the graphical data for a scene, pixels are generated for each of the primitives in the scene.
In conventional Z-buffer systems, as each pixel is generated, its Z coordinate (Znew) is compared with the Z coordinate previously stored in the Z-buffer (Zold). Before processing the first primitive for a scene, the Z-buffer is initialized by storing the value corresponding to a maximum distance (Zmax) in the Z-buffer entry for every pixel so that initially Zold corresponds to Zmax. In general, if Znew is less than Zold (indicating that this pixel is closer to the viewpoint than the previous viewpoint), then the pixel is written to the display device and the Z-buffer memory is updated to contain Znew. If Znew is greater than or equal to Zold, then the pixel is not written and the Z-buffer remains unchanged. All of the pixels for a primitive that is completely hidden will ultimately be overwritten in the Z-buffer during this process so that the primitive is not displayed.
In computer graphics, "rendering" is the process of translating a set of data into a picture that can be displayed. In the rendering process, a picture database typically holding polygon data is read, and calculations are performed by the rendering hardware, pixel by pixel, to decide the color of each pixel. A color calculator often performs this functionality. When a polygon is rendered, a color sample is obtained for each pixel that the polygon covers. If over-sampling is carried out, each pixel will have multiple corresponding color samples that are averaged to give the final color of the pixel. Each color sample has an associated Z-value and a location. The Z-buffer stores the smallest Z-value so far encountered for each location. If a color sample has a Z-value smaller than the value for that location as recorded in the Z-buffer, that sample is written into the frame buffer and the Z-buffer is updated. Otherwise, the color sample is discarded.
The Z-buffering process, the color determination of each pixel, as well as many other functions associated with 3-D graphics, such as utilizing different textures that may include different shadings, holes, transparent textures, translucent textures, etc., is typically performed by a rendering engine of a graphics processor. The rendering engine performs these functions utilizing a rendering pipeline. Graphics data flows along a rendering path through the rendering pipeline. Typically, Z-buffering is not performed until the very end of the rendering pipeline. Unfortunately, a major disadvantage of utilizing the conventional Z-buffering process with current rendering pipeline architectures is that it is inefficient in terms of memory usage.

Z-buffering techniques for graphics rendering


A device for moving a movable furniture part, the device including a basic component on which a force accumulator is present such that the movable furniture part under the action of the force accumulator is capable of being put in the opening direction of the movable furniture part. A separate cover component, configured so as to match the basic component, of the device is present, which cover component covers the basic component, wherein connection means on the cover component are configured in such a manner that integration of the device on a counter portion on the item of furniture and/or the guide means is arrangeable using the connection means which are present on the cover component.

In the case of furniture parts such as, for example, drawers, furniture doors, or furniture flaps which are movably received on a basic furniture structure of an item of furniture by way of guide means, devices for influencing the movement of the furniture part are employed. Devices of this type are formed by a unit which is attachable to the furniture part or to the basic furniture structure or the guide means at a suitable point, for example.
In particular, the guide means comprise a sliding guide such as a full pullout or a part pullout, or a pivoting guide such as a furniture hinge.
In the case of modern and user-friendly items of furniture, devices for moving the furniture part are known, which may optionally be provided for making available an additional function, for example, in particular, in order to facilitate a user in opening the furniture part. The additional function is, in particular, adaptable to the type and size of the furniture part. The device for influencing the movement of the furniture part relates to systems for providing a force-assisted opening function for the furniture part, for example. Herein, the type of integration of the device has to be considered in each case.

Device for moving a movable furniture part, and item of furniture


In a static random access memory formed by an array of rows and columns of memory cells, separate bit lines convey a data bit to or from memory cells of separate columns. Gates controlled by an input row address connect only a single memory cell of each column to the bit lines of the column so that only a single memory cell of the column transmits or receives a data bit on the bit line. Gates controlled by a column address connect the bit lines of only a single column to data input and output circuits. During a write cycle, the memory cell connected to each bit line pair attempts to bias the bit line pair in accordance with the state of its stored data bit, but bit line pairs of non-addressed columns are coupled to a voltage source to prevent a row addressed memory cell of that column from strongly biasing the bit lines. Following the end of a write cycle, a precharge circuit temporarily clamps all bit lines to the voltage source to precharge bit line capacitance. The selective clamping of bit lines of non-addressed columns during the write cycle minimizes a charging current spike produced by the precharge circuit.

The present invention relates to a static random access memory having column decoded bit line bias.
A typical static random access memory includes an array of rows and columns of memory cells, each cell storing a data bit. During either a memory read or a memory write cycle, input row and column addresses identify the row and column of the particular memory cell with respect to which it is desired to read out or store a data bit. During a write cycle, a data input circuit receives a data bit from an external bus and passes it to the addressed memory cell for storage therein. During a data read cycle, a data output circuit receives a stored data bit from an addressed memory cell and passes it to the external bus.
Each column of memory cells uses a pair of "bit lines" to convey a data bit between cells of the column and the data input and output circuits. The polarity of bias across the bit lines represents the state of the data bit. However, gates controlled by the row address connect only one cell in each column to the column bit lines, and gates controlled by the column address connect only the bit lines of one column to the data input and output circuits. Thus, during a read or write cycle, only the memory cell residing both in the addressed row and in the addressed column is connected to a data output or input circuit and only that one cell transmits or receives a data bit via the bit lines.
Each memory cell is a relatively weak bistable latch, and when connected to the bit lines, a memory cell attempts to bias the bit lines to a polarity determined by the state of its stored bit. However, the data input circuit has a more powerful output stage, and when connected to bit lines during a write cycle, the data input circuit biases the bit lines to a polarity determined by the state of a memory input bit regardless of the state of a bit stored by the row addressed memory cell connected to the bit lines. The row addressed memory cell responds by setting the state of its stored bit to match the state of the bit line bias.
During a write cycle, the data input circuit biases only the bit lines of the addressed column. But one memory cell of each non-addressed column of the array is connected to the column bit lines during the write cycle, and each of these cells biases its column bit lines in accordance with the state of its stored bit. During a subsequent memory read cycle, the next cell connected to a pair of bit lines may have to change the polarity of the bias on those bit lines. Since the bit lines have inherent capacitance, the extra time required to charge or discharge this capacitance to overcome the bit line prebias reduces the memory access speed.
To improve memory access speed, static random access memories typically include a "precharge" circuit that temporarily clamps all bit lines to a high logic level at the end of the write cycle to remove bit line bias established during the write cycle. This enables an addressed memory cell to more quickly bias its bit lines to the appropriate state during a subsequent read cycle. However, in restoring the charge on all the bit lines of the memory, the precharge circuit produces a large current spike, particularly in large memories having many bit lines. This current spike can cause excessive noise in a memory chip and in the electronic system using the memory chip, and the current spike contributes to rated memory chip power consumption.

Static random access memory having column decoded bit line bias


An apparatus for cloud key management may include a networking interface, a memory, and a processor, coupled to the memory and the networking interface, the networking interface to couple the apparatus to one or more endpoint servers (EPSs) of a cloud service provider (CSP), each EPS including a hardware accelerator, and a management node (MN) of the CSP. The apparatus may further include an accelerator functional unit (AFU) developer interface module operated by the processor to receive cryptographic material (CM) for each of one or more AFU developers (AFUDs) and store it into the memory, the CM includes a public key hash (PKH), and an encryption key (EK) to decrypt an AFU of the AFUD. The apparatus may also include an EK communication module operated by the processor to: receive, from the MN, a request to send to a targeted EPS an encrypted lookup table (LUT), the LUT including PKHs and associated EKs for a set of the one or more AFUDs from which the targeted EPS is authorized to receive AFUs, and in response to the request, send, to the targeted EPS, the LUT.

AFUs, such as, for example, Field Programmable Gate Array (FPGA) bit-streams, have value to AFU developers, those that deploy them and users. As such, developers may choose to encrypt their AFUs, which generally requires a developer to share an encryption key with a cloud service provider (CSP) deploying the AFU. The CSP, which may support AFUs from multiple sources, may then need to manage and establish security schemes to support key usage. While some CSPs may utilize a cloud based Key Management Service (KMS) to provision key material and store keys in a secure database, these keys are typically clear-text when in use in server dynamic random access memory (DRAM) and/or central processing unit (CPU) registers. Thus, current KMSs do not support a secure mechanism to deploy AFU related keys.


An image sensor may include a plurality of imaging pixels with high dynamic range. Each imaging pixel may have a photodiode, a floating diffusion region, and a transfer transistor configured to transfer charge from the photodiode to the floating diffusion region. Each imaging pixel may also include an overflow capacitor and an overflow transistor interposed between the photodiode and the overflow capacitor. A dual conversion gain transistor may be interposed between the overflow capacitor and the floating diffusion region. To reduce noise associated with operation of the pixel, a ring-shaped conductive layer may form a gate for both the overflow transistor and the dual conversion gain transistor. This common gate may be set to an intermediate level during integration to allow charge to overflow past the overflow transistor to the overflow capacitor. The common gate may also be used to assert the dual conversion gain transistor.

This relates generally to image sensors, and more specifically, to image sensors configured to produce high dynamic range (HDR) images.
Modern electronic devices such a cellular telephones, cameras, and computers often use digital image sensors. Imagers (i.e., image sensors) are formed from a two-dimensional array of image sensing pixels. Each pixel may include a photosensor such as a photodiode that receives incident photons (light) and converts the photons into electrical charges. Conventional image pixel arrays include frontside illuminated image pixels or backside illuminated image pixels. The image sensors may include photodiodes and other operational circuitry such as transistors formed in a front surface of the substrate. A single image sensing pixel in the two-dimensional array of image sensing pixels includes a single photosensitive region, a color filter formed over the photosensitive region, and a single dome-shaped micro-lens formed over the color filter.
Conventional imaging systems may have images with artifacts associated with low dynamic range. Scenes with bright and dark portions may produce artifacts in conventional image sensors, as portions of the image may be over exposed or under exposed. Conventional imaging systems may also have a lower signal-to-noise ratio than desired.
It would therefore be desirable to provide image sensors having improved dynamic range with reduced noise.

Image sensors having imaging pixels with ring-shaped gates

SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC


A power supply circuit, wherein a power supply in a backup system is operational effectively even when a normal power supply to be used at a normal operation is turned off, including an A power supply system for supplying a first voltage to a circuit unit at a normal operation and a backup B power supply system, which starts to operate instantly when the A power supply system becomes abnormal to supply the first voltage to the circuit unit; wherein the B power supply system includes a regulator for outputting a second voltage equivalent to the first voltage, and a feedback circuit for detecting a voltage to be applied to the circuit unit and feeding back the detected voltage to the regulator; and the regulator adjusts an output voltage thereof, so that the voltage to be applied to the circuit unit becomes the first voltage when the voltage detected by the feedback circuit is lower than the first voltage.

1. Field of the Invention
The present invention relates to a power supply circuit and an electronic device supplied with power from the power supply circuit, and particularly relates to a power supply circuit provided with a backup system and an electronic device supplied with a power from the power supply circuit.
2. Description of the Related Art
In an electronic device (electronic equipment), such as a digital equipment, when the power is turned off (cutoff) and a voltage of a power supply and a current become unstable or when a power cannot be normally supplied, for example, due to an instant voltage down (temporary blackout), etc., the problems described below may occur.
(1) When the power supply voltage becomes low and an operation voltage of electronic device components becomes insufficient, the electronic device may runaway, for example, because values of a program and data read from a RAM in the electronic device become abnormal or an operation of a CPU in the electronic device becomes unstable, etc. Also, abnormal information may be stored in a recording medium, such as a flash memory and a disk.
(2) The flash memory, etc. is, for example, an EEPROM, so that the power supply has to be kept for a while to execute writing by receiving an instruction from the CPU as a control unit to save processing data, which has to be kept when turning off the power. If the power is not kept during the time, data inside the flash memory, etc. may be destroyed.
To prevent such disadvantages, even when the power is turned off, the power has to be supplied for a while until an operation of turning off the power is completed for performing a saving processing of the memory.
When turning off the power, to supply a voltage desired to be kept until operations of circuits, such as a memory and a CPU, in the electronic device, the countermeasures described below have been taken in the related art.
As shown in FIG. 1, by providing a capacitor 14 having a largish capacitance in a circuit composed of a power supply 11 of, for example, 5V, a constant voltage power supply 12 for outputting a constant voltage of, for example, 2.5V and a circuit unit 13, such as a flash memory, CPU and RAM, so that the capacitor 14 maintains the power supply voltage for a predetermined time required to backup processing even after turning off the power supply 11.
However, in this type of a power supply circuit, the capacitor 14 having a large-size capacitor, that is, a large capacitor has to be provided outside.
Comparing with the circuit configuration shown in FIG. 1, the circuit shown in FIG. 2 is provided with a power supply 15 having a larger current capacity instead of the power supply 11 and provided with a capacitor 14 having a large capacitance at the output side of the power supply 15.
However, in this type of a power supply circuit, the power supply 15 having a large current capacity has to be provided and, furthermore, the capacitor having a large capacitance, that is, a large capacitor has to be provided outside.
A circuit shown in FIG. 3 is provided with a B-system for backup in addition to an A-system composed of a power supply 11 of, for example, 5V, a constant voltage power supply 12 for outputting a constant voltage of, for example, 2.5V shown in FIG. 1. The B-system includes, for example, a second power supply 21 of 5V in a different system from that of the power supply 11, a second constant voltage power supply 22 for outputting a constant voltage of, for example, 2.5V, and a diode 23 for preventing a reverse current flow. Preferably, a Schottky barrier diode having a characteristic of a low voltage drop is used as the reverse flow preventing diode 23.
Normally, the circuit unit 13 such as a flash memory, a CPU and a RAM, etc. is supplied with a voltage of, for example, 2.5V from the first constant voltage power supply 12 in the A-system. A voltage of, for example, 2.5V is also supplied from the second constant voltage power supply 22 in the same way as the first constant voltage power supply 12, but the voltage from the second constant voltage power supply 22 becomes lower than the voltage from the first constant voltage power supply 12 due to a voltage drop (falls) in the reverse flow preventing diode 23, so that power is not supplied from the second constant voltage power supply 22 to the circuit unit 13. Also, a voltage in the A-system is not supplied to the B-system because of the reverse flow preventing diode 23.
When the first power supply 11 is turned off, an output voltage of the first constant voltage power supply 12 is lowered to 0. Since the voltage of the power supply in the B-system is normal, the circuit unit 13 such as a flash memory, CPU and RAM, etc. is supplied with a voltage from a power supply circuit in the B-system, that is, the second power supply 21 and the second constant voltage power supply 22 through the reverse flow preventing diode 23.
Even when using the Schottky barrier diode, showing a low voltage drop as the reverse flow preventing diode 23, however, the forward voltage drops, for example, by 0.4V or so, so that a voltage applied to the circuit unit 13 such as the flash memory, CPU and RAM, etc. becomes 2.1V or so even if a voltage of 2.5V is output from the second constant voltage power supply 22. This voltage is lower by about 20% than the drive voltage of the circuit unit 13 such as the a flush memory, CPU and RAM, etc. operating at a rated voltage of 2.5V, consequently, operations of the circuit unit 13 such as the flash memory, CPU and RAM, etc. may be adversely affected.
To overcome the disadvantages above, the raise of output voltages of the second power supply 21 and the second constant voltage power supply 22 may be considered. However, the reverse flow preventing diode 23 flows a current in a forward direction when a power supply voltage in the B-system is raised, and there is a possibility that power is supplied from the power supply in the B-system to the circuit unit 13 such as the flash memory, CPU and RAM, etc. even in a normal state, so that the power supply circuit may be adversely affected in terms of a current capacity, etc., systematically as the power supply in some cases.
The forward voltage of the diode changes due to a temperature and the characteristics vary due to an element, and thus an unfavorable result has been brought in a low voltage range in some cases.
From the above viewpoint, a memory and a CPU to be used are often operated by relying on a capable performance of being operational even at a low voltage at the time of saving.
Particularly in a flash memory, stored data may become unreadable or destroyed if an operation in the flash memory continues when the CPU normally starts a shut down operation.
FIG. 4 is a view of the configuration of another power supply circuit of the related art.
The power supply circuit shown in FIG. 4 includes an alternating power supply AC of a commercial frequency, for supplying a power to the circuit unit 13 such as a flash memory, CPU and RAM, etc., a power supply switch 32, a first rectifier circuit 10, a DC-DC converter 11, a first constant voltage circuit 12, a standby (backup) transformer 20, a second rectifier circuit 21, a second constant voltage circuit 22 and a reverse flow preventing diode 23.
When comparing the power supply circuit shown in FIG. 4 with that shown in FIG. 3, the power supply switch 32, the first rectifier circuit 10, the DC-DC converter 11 and the first constant voltage circuit 12 are included as a power supply circuit in the A-system; and the circuit illustrated as the first power supply 11 in FIG. 3 is configured by the power supply switch 32, the first rectifier circuit 10 and the DC-DC converter 11 in FIG. 4. Also, the power supply circuit in the B-system is configured by the standby transformer 20, the second rectifier circuit 21, the second constant voltage circuit 22 and the reverse flow preventing diode 23; and the circuit illustrated as the second power supply 21 in FIG. 3 is configured by the standby transformer 20, the second rectifier circuit 21.
In the power supply voltage shown in FIG. 4, in a normal operation, the power supply switch 32 is in a turned-on state, and power is supplied to the circuit unit 13 from the A-system power supply circuit including the first rectifier circuit 10, DC-DC converter 11 and first constant voltage circuit 12. In this state, the B-system power supply circuit, that is, the standby transformer 20, the second rectifier circuit 21 and the second constant voltage circuit 22 are also in operation, but power is not supplied from the power supply circuit in the B-system to the circuit unit 13 due to a voltage drop in the reverse flow preventing diode 23.
For example, when the power supply switch 32 is turned off (an open state), power supply from the A-system circuit to the circuit unit 13 is suspended. However, since the power supply circuit in the B-system is in operation, power is supplied from the B-system power supply circuit to the circuit unit 13 without any discontinuity.
The operation of the power supply circuit in FIG. 4 explained above is the same as that of the power supply circuit explained with reference to FIG. 3.
In the same way as the first constant voltage circuit 12 and the second constant voltage circuit 22 shown in FIG. 3, when assuming that a constant voltage of 2.5V is output from the first constant voltage circuit 12 and the second constant voltage circuit 22 shown in FIG. 4, at the time of supplying power from the B-system power supply circuit to the circuit unit 13, a lack of a voltage to the circuit 13 due to a voltage drop in the reverse flow preventing diode 23 explained above becomes disadvantageous.
On the other hand, when an output voltage of the second constant voltage circuit 22 is raised to improve the voltage shortage, the disadvantageous effects explained above are caused.
The Japanese Unexamined Patent Publication No. 11-175203 discloses a technique of saving data not by using a backup power supply, etc. but by using power generated by using an inertial force of a rotating recording medium.

Power supply circuit and electronic device


Embodiments of the invention provide a video display technique with which a stable video with a high contrast can be obtained according to brightness of a screen. In one embodiment, a video signal processing system for a video display apparatus which performs display on the basis of a video signal comprises a gain control module configured to provide a feedback signal based upon maximum luminance level information and average luminance level information of a luminance signal corresponding to the video signal, the feedback signal being used to control a gain of the luminance signal; and a correction module configured to apply a gamma correction based upon the average luminance level information to the video signal after the gain of the luminance signal has been controlled by the gain control module.

The present invention relates to a technique for displaying a video on the basis of a television signal or a video signal inputted from a personal computer or the like.
As a conventional art related to the present invention, there is one described in JP-A-8-317250 (Patent Literature 1). In the laid-open patent application, there is described a technique for calculating an APL and a histogram from an inputted video signal to analyze them, expanding ranges of a minimum level and a maximum level of the video signal to increase a gamma value of input/output characteristics corresponding to the vicinity of the APL, and increasing a contrast ratio of a displayed picture.
In a video display apparatus using a fixed pixel device such as a PDP or a liquid crystal panel, a higher contrast ratio corresponding to brightness of a screen is desired. However, in the above-mentioned conventional art, there is a defect in this respect because, for example, gain control of a video signal is not associated with a luminance level. In addition, calculation and analysis processing of a histogram are also required, which complicates the constitution and signal processing.

Video signal processing circuit, video display apparatus, and video display method


A method for cleaning tubes and heat exchangers provides a cavitation enhancement unit between a source of pressurized fluid an a lance. The pressurized fluid flows through jets, which impart a high speed rotation to a set of propellers, preferably square in profile canted at a 15° angle. Generation of cavitation develops a cleaning vibration in the fluid discharged from the lance.

A heat exchanger is normally formed of a plurality of tubes oriented generally parallel to one another. In normal operation, a fluid to be heated or cooled is delivered through the inside of the tubes of such a heat exchanger. The outside surface of the tubes are contacted with a fluid which adds heat or removes heat as required. The plurality of generally parallel tubes forms a bundle. A set of end plates, known as heads, commonly support the bundle of tubes at each end.
Heat exchangers usually operate in a continuous fashion, often for months at a time. However, such continuous operation may be periodically interrupted to clean the tubes. The cleaning process is necessary to remove residue which collects on the inside surface of the tubes which reduces their heat transfer capability. The tubes are normally formed of metal which has a relatively high thermal conductivity. The material which may coat the interior of the tubes, however, has a much lower thermal efficiency for heat transfer. Therefore, the coating formed on the interior of the tubes is detrimental to the efficiency of the operation of the heat exchanger.
As residue builds up on the inside surface of a heat exchanger tube, the tube becomes less and less efficient. One way to counteract this effect is to raise the temperature differential across the tube. However, there are limits to this solution. For instance, the metal used in the tubes of the heat exchanger has a limited capacity for heat as a result of metallurgical considerations. Exceeding the design temperature differential across through the tubes increases fatigue and therefore reduces the useful lifetime of the heat exchanger.
In a well known U-tube design, the bundle of tubes takes a 180° bend or elbow at more or less the mid-point of the respective tubes. Fluid enters an inlet box which is separated by a divider plate from an outlet box. The fluid then flows through the head, through the tubes in first one direction then the reverse direction, back through the head and finally into the outlet box on the other side of the divider plate. Cleaning the tubes involves removing the accumulated coating material on the inside of the tubes and the difficulty of cleaning the inside surfaces of the tubes is exacerbated by the bend in the tubes. Also, as exchanger designs have improved, the effective length of the tubes has increased. This makes the task of cleaning the tubes more difficult because the long and relatively narrow tubes do not permit easy access to the tubes.
One way that the tubes can be cleaned is by pumping water or perhaps chemically active solvents into the tubes. That is successful but it has limitations. Moreover, since a typical heat exchanger includes a large number of tubes, it is necessary to undertake the cleaning in a repetitive fashion so that a large number of tubes can be cleaned.
In my U.S. Pat. No. 5,423,917, I described a system and a method for cleaning heat exchanger tubes. The system described therein has proven very successful. However, the system includes a control panel with a ganged set of valves to set up a shock wave to be injected into a tube. For particularly stubborn and tenacious fowling, especially involving hundreds of tubes, this manual alignment of the control panel valves can become tiresome and tedious. In related application titled Pump Valve Mechanism, I describe a solution to this problem. The cleaning action of that system, however, can be enhance by creating vapor bubbles in the stream of fluid. The cavitation creates a high intensity vibration, particularly at the harmonics of the region to be cleaned, thereby enhancing the cleaning operation of the system.

Cleaning apparatus with cavitation enhancement unit


The invention relates to novel heterocyclic compounds and pharmaceutical preparations thereof. The invention further relates to methods of treatment using the novel heterocyclic compounds of the invention.

Glutamine supports cell survival, growth and proliferation through metabolic and non-metabolic mechanisms. In actively proliferating cells, the metabolism of glutamine to lactate, also referred to as "glutaminolysis" is a major source of energy in the form of NADPH. The first step in glutaminolysis is the deamination of glutamine to form glutamate and ammonia, which is catalyzed by the glutaminase enzyme. Thus, deamination via glutaminase is a control point for glutamine metabolism.
Ever since Warburg's observation that ascites tumor cells exhibited high rates of glucose consumption and lactate secretion in the presence of oxygen (Warburg, 1956), researchers have been exploring how cancer cells utilize metabolic pathways to be able to continue actively proliferating. Several reports have demonstrated how glutamine metabolism supports macromolecular synthesis necessary for cells to replicate (Curthoys, 1995; DeBardinis, 2008).
Thus, glutaminase has been theorized to be a potential therapeutic target for the treatment of diseases characterized by actively proliferating cells, such as cancer. The lack of suitable glutaminase inhibitors has made validation of this target impossible. Therefore, the creation of glutaminase inhibitors that are specific and capable of being formulated for in vivo use could lead to a new class of therapeutics.