This invention relates generally to a codon optimized nucleic acid encoding a retinitis pigmentosa GTPase regulator (RPGR) protein. The nucleic acid has enhanced stability during plasmid production relative to a wildtype cDNA encoding the RPGR protein. The invention also relates to expression cassettes, vectors, and host cells comprising the codon optimized nucleic acid. Methods for preparing a recombinant adeno-associated (rAAV) expression vector comprising the codon optimized nucleic acid sequence are also provided. The nucleic acids, expression cassettes, vectors, and host cells provided may be useful in the large scale production of rAAV expression vectors for gene therapy applications.

Retinitis pigmentosa (RP) is an inherited degenerative disease of the retina that affects approximately one in 3,500 individuals, with an estimated 1.5 million patients worldwide. See Churchill et al., 2013, Invest. Ophthalmol. Vis. Sci. 54(2): 1411-1416. RP is caused by progressive loss of rod and cone photoreceptors, resulting in night blindness followed by loss of visual fields. The disease may result in legal or even complete blindness. Mutations in the retinitis pigmentosa GTPase regulator (RPGR) gene account for greater than 70% of the cases of human X-linked retinitis pigmentosa (XLRP), the most severe subtype of RP. See Beltran et al., 2012, PNAS 109(6): 2132-2137 and Bader et al., 2003, Invest. Ophthalmol. Vis. Sci. (44)4: 1458-1463.
Alternative splicing of the RPGR gene results in expression of multiple isoforms of the RPGR protein. The mRNA for isoform A contains all 19 exons of the gene, while the mRNA for isoform C contains exons 1 to 15 and a large part of intron 15. Intron 15 is a purine-rich region that contains highly repetitive sequences that code for glutamate and glycine repeats (EEEGEGEGE in human (SEQ ID NO: 9) and EEGEGE in mouse (SEQ ID NO: 10)), see Vervoort et al., Mutational hot spot within a new RPGR exon in X-linked retinitis pigmentosa. Nat Genet 2000; 25:462-6. Isoform A is constitutively expressed in all tissues while isoform C, which is also referred to as "ORF15", is the predominant form expressed in the connecting cilium of photoreceptor, see Hong et al., Invest Ophthalmol Vis Sci 2002; 43:3373-82, and Hong et al., Invest Ophthalmol Vis Sci 2003; 44:2413-21.
A total of 55% of RPGR-related XLRP is caused by mutations in ORF15, all of which result from deletions that lead to truncated proteins. Most of the other cases are caused by mutations in exons 1-13, which can be either missense or nonsense mutations, with a small number caused by mutations in introns or large deletions. No cases have been identified due to mutations in exons 16 to 19.
Recent studies have demonstrated the potential of gene therapy approaches to treating XLRP caused by mutations in the RPGR gene. For example, Beltran et al. have shown that subretinal injections of adeno-associated virus (AAV) vectors expressing human RPGR increased rod and cone photoreceptor function in a canine model of XLRP.
However one of the challenges in large-scale production of AAV vectors for clinical use is that nucleic acid sequences encoding a protein of interest such as RPGR may be unstable, resulting in the accumulation of several mutations and deletions. For example, the RPGR gene contains a region of 1.2 kb called ORF15 near the 3′ end of the cDNA that is highly repetitive and GA rich. This region is a mutation "hot spot" in population. This repetitive region is very unstable during cloning and vector preparation and clones obtained generally contain mutations and deletions. These mutations can potentially alter or eliminate RPGR protein function, limiting the use of this protein in gene therapy applications. Therefore a need exists to identify methods of stabilizing RPGR cDNAs during large-scale production of AAV vectors.

Codon optimized nucleic acid encoding a retinitis pigmentosa gtpase regulator (RPGR)

Applied Genetic Technologies Corporation


A catheter includes a tubular proximal shaft having relatively high rigidity, a tubular distal shaft having rigidity lower than that of the proximal shaft, a tubular intermediate section disposed between the proximal shaft and the distal shaft, a hub arranged near a proximal end of the proximal shaft, a balloon provided to a distal portion of the distal shaft to be in fluid communication, and a guide wire lumen having a distal aperture located on a distal end side of the distal end of the balloon and a proximal aperture located on a proximal end side of the proximal end of the balloon, through which a guide wire is inserted, wherein a reinforcing member consisting of a braided member made of at least one linear member, is embedded in the intermediate section. The catheter is capable of effectively avoiding kink caused by heavy concentration of flexural stress.

This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 11-274379, filed Sep. 28, 1999, the entire contents of which are incorporated herein by reference.
The present invention relates to a catheter such as a balloon catheter, or an intravascular therapeutic or diagnostic catheter.
In accordance with the development of the microcatheter, it becomes possible to perform microvascular or intravascular therapy and diagnosis, which has been considered impossible with conventional catheters. Examples of the microcatheter are catheters for percutaneous transluminal coronary angioplasty, used for cardiac infarction or angia pertoris (referred to as a balloon catheter hereinafter). In the operation of angioplasty, it is necessary to exchange one catheter for another many times. The catheter must be exchanged, for example, when the balloon size is changed or a diagnostic or treatment device for diagnosing or treating a vicinity of a stenosed portion is changed. As an example of the method of exchanging a catheter, there is a conventionally known technique in which a long exchange guide wire is used. However, it requires not only a long period of time to handle such a long wire, but also at least two operators for the operation, and therefore the handling of the wire is not easy. In order to solve this drawback, a so-called xe2x80x9crapid exchangexe2x80x9d type catheter has been proposed. The catheter of this type has a structure in which only the distal portion thereof tracks the guide wire.
Examples of the catheter of the rapid-exchange type are discussed in U.S. Pat. Nos. 5,040,548, 5,061,273 (to Yock), U.S. Pat. No. 4,762,129 (to Bonzel), U.S. Pat. No. 5,135,535 (to Kramer) and the like.
Here, the rapid-exchange type catheter disclosed in PCT Publication WO93/15786 will now be described in detail. This catheter consists of a proximal shaft, a distal shaft, a balloon and a tube for guide wire lumen, and a core wire which extends in the direction of the distal shaft, is bonded to the proximal shaft. The core wire imparts rigidity to the distal shaft having a relatively low rigidity, which is attached to the distal side of the proximal shaft having a relatively high rigidity. In this manner, kinking in the distal shaft due to heavy concentration of flexural stress, can be prevented.
However, in this catheter, the core wire is present inside the inflation lumen, which narrows the cross sectional area of the inflation lumen. This causes the problem of inhibiting of shortening the balloon inflation/deflating time. As a result, the time for stemming the blood flow during the inflation of the balloon is prolonged, putting stress on a patient. Not only the rapid-exchange type catheter has such a drawback, but it is also common to all the catheters of the type in which a core wire is installed in a flow path as a reinforcing member.
In the meantime, PCT Publication WO92/03178 discloses a rapid-exchange catheter having such a structure that an intermediate sleeve section is provided between a proximal shaft made of a metal tube and a distal shaft having high flexibility, and a coil member is provided around the outer circumference of the sleeve section for reinforcement.
However, even if a coil member is provided around the outer circumference of the intermediate sleeve section, it is not possible to effectively avoid kinking caused by heavy concentration of flexural stress. The coil member is would in only one direction toward the distal end of the catheter, and therefore as the operator rotates the catheter in an opposite direction while gripping the hub, the wound coil is loosened and accordingly gaps between adjacent coil wires are widened, thereby causing deterioration of the kink resistance. Moreover, because the intermediate sleeve section is superfluously bent due to the loosening of the coil, there may be caused a problem that torque or pushing force, which is provided on the proximal end of the catheter, is hard to be surely transmitted to the distal end of the catheter.
The object of the present invention is to provide a catheter capable of effectively avoiding kink caused by heavy concentration of flexural stress, without narrowing cross sectional area of the inflation lumen.
A balloon catheter of the present invention includes: a tubular proximal shaft having a relatively high rigidity; a tubular distal shaft having rigidity lower than that of the proximal shaft; a tubular intermediate section disposed between the proximal shaft and the distal shaft; a hub arranged near a proximal end of the proximal shaft, to which a pressure applying device is attached; a balloon provided to a distal portion of the distal shaft to be in fluid communication, to which pressure is applied from the hub; and a guide wire lumen having a distal aperture located on a distal end side of the distal end of the balloon and a proximal aperture located on a further proximal end side of the proximal end of the balloon, through which a guide wire is inserted; wherein a reinforcing member consisting of a braided member formed by braiding at least one linear member, is embedded in the intermediate section.
A catheter of the present invention includes: a proximal shaft having relatively high rigidity; a distal shaft having rigidity lower than that of the proximal shaft; an intermediate section disposed between the proximal shaft and the distal shaft; a hub arranged near a proximal end of the proximal shaft; a treatment device (device for therapy or diagnose, such as an ultrasonic diagnostic device, a laser, an atherectomy cutter, a medicine supply device, a radio frequency generator or an ultrasonic therapy device) attached on a distal portion of the distal shaft; and a guide wire lumen having a distal aperture located on a distal end side of the treatment device and a proximal aperture located on a proximal end side of the proximal end of the treatment device, through which a guide wire is inserted; wherein a reinforcing member consisting of a braided member formed by braiding at least one linear member, is embedded in the intermediate section.
In the present invention, it is preferable that the distal shaft having relatively high rigidity should be made of a metal tube. Further, the present invention may be of a structure in which the intermediate section has an inner layer and an outer layer, and the reinforcing member is embedded between the inner surface and outer surface of the intermediate section, or of a structure in which the reinforcing member is embedded in the intermediate section such that it is exposed to an internal lumen of the intermediate section.
It is preferable in the present invention that the reinforcing member should be made by braiding linear member(s) such that there are sections where the inclination angles of the linear member(s) which constituting the reinforcing member are relatively large and relatively small with respect to the axial direction of the intermediate section.
According to the catheter of the present invention, the cross section of the inflation lumen is not narrowed and therefore the balloon inflation/deflation time is not prolonged, unlike in the prior art where the core wire is used. Therefore, it becomes possible to reduce the stress on a patient. Further, the reinforcing member which is made of a braided member exhibits a greater effect of preventing kink, than in the case of a reinforcing member made of a conventional coil member. Furthermore, when the reinforcing member is made by braiding at least one linear member such that there are sections where the inclination angles of the linear member(s) constituting the reinforcement member are relatively large and relatively small with respect to the axial direction of the intermediate section, it becomes possible to vary the rigidity of the shaft gradually. Consequently, the kink can be more efficiently avoided.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.


Staple  Stable, aqueous gel vehicles are provided for the topical application to the skin of irritating active ingredients such as retinoids, particularly tretinoin, with slow release of the active ingredient and minimal irritancy to the skin. The vehicles include a gelling agent effective to form a gel and hold the active ingredient in the aqueous medium for slow release on the skin, and an effective amount of an antioxidant to retard decomposition of the active ingredient. The vehicles and formulations are preferably aqueous emulsions which contain a solubilizing agent for the generally non-water soluble active ingredients, as well as usually an emulsifying agent and/or surfactant. Chelating agents, emollients, preservatives and other adjuvants and additives may also be included in the vehicles and formulations.

Topical retinoids have been widely used for multiple cutaneous disorders, as reported in A. Haas et al. "Selected Therapeutic Applications of Topical Tretinoin." JAAD, 15:870 (1986) (See Table I below). In many instances, the application of tretinoin has alleviated or induced remission in many such conditions, although these disorders reflect a variety of pathogenic mechanisms.
TABLE ISelected Therapeutic Application of Topical TretinoinDisorders with altered keratinizationAcneiform follicular, or nevoidNevus comdeonicusSenile comedonesSteroid folliculitisPsuedofolliculitisFox-Fordyce diseaseHair castsMonilethrixAlopeciaThrichiostasis spinulosaLinear verrucous nevusIchthyosiformEpidermolytic hyperkeratosis(congenital ichthyosiform erythroderma)Ichthyosis vulgarisLamellar ichthyosisX-linked ichthyosisPsoriasiform, hyperkeratotic, or dyskeratoticAcanthosis and psuedoachanthosisnigricansCallositesKeratosis follicularis (Darier's)Keratosis palmaris et plantarisKyrle's diseasePsoriasisReactive perforating collagenosisInfectious/inflammatory disordersMolluscum contagiosumFlat wartsPlantar wartsTinea versicolorLeg ulcersKeloids and hypertrophic scarsMucecutaneous disordersGeographic tongueLichen planusLeukoplakiaXerophthalmia (dry eye)Hairy leukoplakiaPigmentation disordersEphelidesMelasmaPostinflammatory hyperpigmentationMalignant and premalignant disordersActinic keratoses, photoagingKeratoacanthomasMelanomasCertival dysplasisBasal cell epithelioma
It has been demonstrated that prolonged topical application of Vitamin A acid (tretinoin or all-trans retinoic acid) is effective in the treatment of acne (See U.S. Pat. No. 3,729,568 and Kligman, A. M., "Topical Vitamin A Acid in Acne Vulgaris." Arch. Derm., 99: 469-476 (1969)). Kligman utilizes a composition in which Vitamin A acid is dispersed in a water miscible (substantially oil- and fat-free) liquid carrier having high solvating action. The topical application of this Vitamin A acid composition causes irritation of the skin in the treated areas. A presently available gel form with alcohol base or cream formulation also causes irritation. (See U.S. Pat. Nos. 3,906,108 and 4,247,547.)
A cream formulation of tretinoin is presently approved and is commercially available from Ortho Pharmaceutical Company under the trademark RETIN-A. It contains a therapeutically effective amount of tretinoin, a hydrophobic material selected from the liquid and solid fatty acids, fatty alcohols, fatty acid esters, pharmaceutical grades of waxes and hydrocarbons, the latter ranging from liquids through semisolids, such as petrolatum, to solids, and the like, a non-ionic emulsifier, xanthan gum, a preservative, an antioxidant and water. This formulation is more generally acceptable in a low dose 0.025% formulation, but it is still unacceptable to certain individuals with sensitive skin for continued daily applications.
Furthermore, the above tretinoin cream is relatively dense and pasty, and the pharmaceutical base is not elegant. The necessity to stabilize the cream with xanthan gum and to apply daily or twice daily a fatty substrate to the skin leaves a greasy film with a pasty residue.
Therefore, the problem has been to find vehicles for retinoids, particularly tretinoin, and other irritating active ingredients in which the active ingredient would remain stable and non-oxidized in the presence of large amounts of water, while dramatically reducing the amount of irritation caused by the active ingredient. It is also desirable to have a vehicle which can provide sufficient hydration to allow good percutaneous absorption, while at the same time allowing the active ingredient to be spread very thinly over the skin.

Slow release vehicles for minimizing skin irritancy of topical compositions


A method for the preparation of pulp by means of alkaline cooking, in which method spent liquor is transferred to pressurized tanks, and at least one liquor is expanded corresponding to a temperature difference of 1 to 5° C. The generated steam is led to turpentine recovery. Thus, the removal of turpentine and gases dissolved in said liquor is effective, the amount of recovered turpentine increases, and pulp of better washability and higher quality is obtained.

Alkaline pulping processes and especially kraft pulping are dominant in the production of cellulose, because alkaline pulping provides pulp fibers which are stronger than those from any other commercial pulping process. A well-known method for cooking wood chips is the batch process. In a conventional kraft batch process, wood chips are fed to the digester from bins, directly or by conveyor systems, and cooking liquor is added. The cooking liquor includes fresh cooking liquor containing a water solution of sodium hydroxide and sulfur compounds, normally referred to as white liquor, and spent liquor from previous cooks (black liquor) to cover the chips and control the liquor-to-wood ratio. When chips and liquor have been added, the cook is started by introduction of heat either indirectly or directly by steam. The cook itself consists of a heating period and an "at pressure" period. The cooking conditions are usually about 160-180° C., with a pressure equivalent to the corresponding boiling point. At the conclusion of the cook when the delignification has proceeded to the desired reaction degree, a blow valve in the digester is opened and the contents of the digester are discharged into a blow tank, as the hot liquor in the digester flashing into steam and forces the cooked pulp out of the digester.
During the cooking cycle the digester is continuously vented to remove air and other non-condensable gases from the system. Turpentine, steam and other volatile compounds are also released during this venting or gas-off period. If the digester has been heated and vented properly, most of the turpentine will come over by the time the cooking temperature and pressure has been reached (Drew, D. et al., Sulfate Turpentine Recovery, Pulp Chemicals Association, New York, 1971, p. 70). The vapors from the digester go to a separator, where black liquor and/or pulp that have been carried over is separated, and the turpentine, steam and non-condensable gases go to one or more condensers. The condensate, consisting of turpentine and water, goes to a decanter where the two separate. The turpentine overflow goes to the turpentine storage tank. The turpentine recovery of batch digesters is extensively described in the chapter "Turpentine Recovery from Batch Digesters" in the book Sulfate Turpentine Recovery by Drew, D. et al., Pulp Chemicals Association, New York, 1971, p. 65-93.
However, the above-mentioned conventional batch process is energy inefficient and produces pulp of low strength delivery.
Batch processes have therefore been developed for the purposes of, among others, saving energy. From the early 1980's, new emerging efficient kraft batch processes using various kinds of displacements started to gain ground. Characteristic for the liquor displacement batch processes is the recovery of hot black liquor at the end of cooking and reuse of its energy in subsequent batches. Good examples of this development are processes described in, e.g., Fagerlund, U.S. Pat. No. 5,578,149 and Östman, U.S. Pat. No. 4,764,251. The displaced liquors of usually over 100° C. are stored in one or several pressurized accumulators which usually contain a continuous heat recovery system (see, e.g. U.S. Pat. No. 6,643,410). As a result, the energy efficiency of batch cooking has increased.
The quality of the pulp was also improved by the liquor displacement batch method by avoiding digester discharge which utilizes hard hot blow techniques. Gentle digester discharge is typically accomplished by cooling the digester prior to discharge, relieving the overpressure in the digester and then pumping the cooked material from the digester (see, e.g., U.S. Pat. No. 4,814,042). Further development of liquor-displacement kraft batch cooking has also involved the combination of energy efficiency and efficient usage of residual and fresh cooking chemicals to achieve facilitated delignification and high pulp strength (see, e.g., U.S. Pat. Nos. 5,183,535 and 6,643,410). This can be accomplished by arranging the displacement at the end of the cook to first recover the "mother" black liquor, hot and rich in residual sulfur, in one accumulator and then to recover the portion of black liquor contaminated by wash filtrate and lower in solids and temperature in another accumulator. The accumulated black liquors are then reused in reverse order to impregnate and react with, respectively, the next batch of wood chips prior to finalization of the cook with hot white liquor. By this means it is has become possible to start a kraft cook with a high charge of sulfur and a low charge of hydroxyl ion and thus carry out important sulfur-lignin reactions in the hot black liquor pretreatment phase.
In liquor-displacement batch processes, the chips are normally totally covered by liquor. Typically, higher liquor-to-wood ratios are used compared to conventional batch cooking as higher liquor-to-wood ratio enables liquor displacements and more efficient liquor circulations. Moreover, the higher liquor-to-wood and the displacement procedure results in more even distribution of chemicals and heat throughout the contents of the digester. As a result, the produced pulp is more uniform.
Thus, the above-mentioned development of the batch cooking technology which mostly took part in the 1980's has been characterized by improvements in terms of energy savings but also provided improved strength delivery of the delignified cellulosic material and made it possible to extend delignification in cooking.
It has, however, been noticed that the introduction of liquor displacement batch systems results in lower turpentine yield. Minor attention has been paid to turpentine recovery as in general; the turpentine recovery has played a minor economical role for mills. In studies, it has however been found that the turpentine is partly found in the pulp discharged from the digester and/or in the spent liquors. Other, non-condensable gases are also influenced by the digester and cooking plant venting and thus turpentine recovery. Thus, other gases may also be found in the discharge pulp and/or in the spent liquors when venting is ineffective. In black liquors, turpentine affects for example the soap solubility and thus changes the behavior of soap. A high turpentine content in black liquors lowers the soap solubility. Soap separation from spent liquors is affected in e.g. the pulp washing area. During the cooking cycle, ineffective removal of turpentine decreases the solubility of extractives, e.g. soap, from the lignocellulosic material into the cooking liquor. The turpentine affects soap in the same way in a pulp suspension and thus higher levels of turpentine cause low solubility of extractives into the liquor phase of a pulp suspension. As a consequence, the pulp is difficult to de-water and wash, and technical problems in washing occur when relieving of turpentine is ineffective. Problems in washing can for example cause production difficulties; increase chemical consumption and lower quality of produced pulp due to higher wash losses in bleach stages. High turpentine levels in the discharge pulp are an environmental harm and safety risks may also occur, as the volatile compounds may evaporate in e.g. the washing plant. As recent studies have shown that high-quality pulp, efficient pulp production and high recovery efficiency of turpentine often work together; development of the liquor-displacement batch system has to occur.
In prior liquor-displacement batch processes, the digester is either degassed to a pressurized spent liquor accumulator wherefrom the gases are vented to the turpentine recovery (e.g. in the RDH system (Foran, C. D., Recovery notes for Kamyr Digester Systems—Cold blow Batch Digester Systems—TMP Process Condensor, Decanter and Storage Systems, 1994 PCA/TAPPI By-Product Recovery Short Course, Mar. 14-16. 1994, Stone Mountain, Ga., p. 17-19)) or the digester is directly vented to the turpentine recovery system (e.g. the cold-blow system (see e.g., Petterson, B., Ernelfeldt, B., "Advances in technology make batch pulping as efficient as continuous", Pulp & Paper November 1985, p. 90-93)). Combinations of the above-mentioned degassing methods are also found, i.e. both direct degassing of digesters and degassing of accumulators to turpentine recovery. The turpentine recovery itself, i.e. liquor separator, condensers and decanters, does not essentially differ from the one used in conventional batch cooking. When applying degassing from the digester to a pressurized spent liquor accumulator, the accumulator degassing to the turpentine recovery is based on pressure control and the target is to retain overpressure and more particularly a constant overpressure in said accumulator, since the overpressure forces the liquor through heat recovery to an atmospheric tank and suppresses uncontrolled boiling of the liquor. Consequently, little vaporization of volatile compound occurs in the accumulator. The turpentine is solubilized in the black liquor and turpentine recovery will be lower (Foran, C. D., Recovery notes for Kamyr Digester Systems—Cold blow Batch Digester Systems—TMP Process Condensor, Decanter and Storage Systems, 1994 PCA/TAPPI By-Product Recovery Short Course, Mar. 14-16. 1994, Stone Mountain, Ga., p. 18).
Typical of prior liquor displacement processes are also that the digester has a high starting temperature in the actual cooking phase when circulation is applied following chip pretreatment. Accordingly, the digester is heated to the cooking temperature more rapidly than in conventional cooking. Thus, the time at gas-off is short, as no gas-off occurs during chip pretreatment.
Other differences relative to conventional batch cooking are that the digester is operated at a higher liquor-to-wood ratio. Therefore, the turpentine dissolves in the black liquor and the amount of recovered turpentine decreases compared to conventional batch cooking, Methods wherein a portion of hot liquor is removed to create a liquid-vapor interface in the top of the digester followed by removal of the vapors disposed directly to the turpentine recovery have also been suggested, as described in PCT application WO 98/56978 and application 951399. However, our experience of the so-called Cold Blow process using a clear liquid-vapor interface in the top of the digester, liquor circulation to above the liquor-vapor interface and direct degassing to the turpentine recovery, as well as of mill trials using the above-mentioned methods wherein the digester was not hydraulically full, a liquor-gas interface was present and direct degassing was used, also showed that the turpentine yield was not at the level of conventional batch cooking.
Accordingly, a need for an improved liquor-displacement batch process, which more efficiently recovers turpentine and removes other volatile gases more efficiently from the cooking process, is evident.
In continuous cooking processes, the chip material is heated before introduction of the chips into the digester with flash steam obtained from flashing the hot black liquor. The turpentine and non-condensable gases are not removed from the digester during continuous cooking. Instead, the turpentine must be removed from the spent (black) liquor extracted, typically at a temperature of 150-170° C., from the digester. In continuous cooking, the spent liquor is flashed before going to evaporator feed storage. The liquor is flashed in multiple stages, typically twice to a temperature of about 100° C. The primary flash steam is returned to the steaming vessel to preheat the incoming chips. The underflow from the primary flash tank is flashed again. The flash steam from the secondary flash tank in older continuous cooking designs is combined with the gases from the steaming vessel and sent on to a cyclone separator, condensers and turpentine decanter. The primary flash steam contains more turpentine than the secondary flash steam. The drawback of older designs is that the turpentine in the primary flash steam is condensed in the steaming vessel.
In newer designs of continuous digesters, a portion of the secondary flash steam is returned to the bottom of the chip bin to pre-steam the chips. As the secondary flash steam is returned to heat chips in the chip bin, the turpentine in the secondary flash steam condenses on the chips. The heat released from the primary flash steam to heat the chips in the steaming vessel results primarily from the condensation of water. This results in venting of turpentine from the steaming vessel by preventing condensation of primary flash steam turpentine on cold chips in the steaming vessel. In newer continuous cooking designs, the gases from the steaming vessel are sent on to a cyclone separator, condensers and turpentine decanter. Portions of the secondary steam are also conducted to the condensers and turpentine decanter. However, the turpentine recovery yields of continuous cooking is clearly lower than from conventional batch digesters. More details of the turpentine recovery in continuous cooking is found in Foran, C. D., Recovery notes for Kamyr Digester Systems—Cold blow Batch Digester Systems—TMP Process Condensor, Decanter and Storage Systems, 1994 PCA/TAPPI By-Product Recovery Short Course, Mar. 14-16. 1994, Stone Mountain, Ga., p. 4-14. Accordingly, a need for improved recovery of turpentine and other volatile compounds is also evident in continuous cooking.

Method for improved turpentine recovery from modern cooking plants


Methods and apparatus relating to network routing protocols to support power savings in network elements. A most utilized link path network topology for a computer network is discovered using a routing protocol such as a Spanning Tree, link-state, or distance vector routing protocol. In view of the most utilized link path network topology, links are identified as candidates for power management under which a power state of the link and associated network ports are managed to save power under applicable link conditions, such as low utilization. Link power-state change conditions are detected, and in response a corresponding change to the power state of a link is effected by changing the power-state of the network ports at the ends of the link. Power state changes include putting a link into a reduced power state, taking a link offline, and powering a link back up.

Ever since the introduction of the microprocessor, computer systems have been getting faster and faster. In approximate accordance with Moore's law (based on Intel® Corporation co-founder Gordon Moore's 1965 publication predicting the number of transistors on integrated circuits to double every two years), the speed increase has shot upward at a fairly even rate for nearly three decades. At the same time, the size of both memory and non-volatile storage has also steadily increased, such that many of today's personal computers are more powerful than supercomputers from just 10-15 years ago. In addition, the speed of network communications has likewise seen astronomical increases.
Increases in processor speeds, memory, storage, and network bandwidth technologies have resulted in the build-out and deployment of networks with ever substantial capacities. More recently, the introduction of cloud-based services, such as those provided by Amazon (e.g., Amazon Elastic Compute Cloud (EC2) and Simple Storage Service (S3)) and Microsoft (e.g., Azure and Office 365) has resulted in additional network build-out for public network infrastructure, and addition to the deployment of massive data centers to support these services which employ private network infrastructure. Additionally, the new generation (i.e., 4G) of mobile network data services is expected to significantly impact the utilization of land-line networks in the near future. The result of these and other considerations is that the utilization of computer networks is expected to continue to grow at a high rate for the foreseeable future.
Typically, computer network deployments are designed to provide sufficient levels of Quality of Service (QoS) during peak workload conditions and/or over sustained periods of operation. These networks are also designed to be highly reliable, typically with built-in redundancies in both equipment and network links. Moreover, modern network routing schemes have inherent built in redundancies, since packets can typically be routed along many different routes between two network endpoints. This is facilitated via the widespread deployment of numerous network elements comprising switches, routers, and bridges that are configured to dynamically route network traffic via high-bandwidth links between the network elements using well-known protocols such as TCP/IP, UDP, RIP, Ethernet, etc.
The result of network deployments designed for peak workload conditions is that networks may have excess capacities during fairly lengthy timeframes. For example, for a given time-zone, utilization of networks may be dramatically lower during late-night and early-morning hours. This provides an opportunity for power savings, by selectively reducing network capacity while maintaining full routing functionality (meaning a packet can still be routed between any two endpoints via the network or subnet).

Network routing protocol power saving method for network elements


A mechanical compression method can be used to tune semiconductor nanoparticle lattice structure and synthesize new semiconductor nanostructures including nanorods, nanowires, nanosheets, and other three-dimensional interconnected structures. II-VI or IV-VI compound semiconductor nanoparticle assemblies can be used as starting materials, including CdSe, CdTe, ZnSe, ZnS, PbSe, and PbS.

Nanoparticles (e.g., sizes below about 100 nm) of II-VI semiconductor compounds have been known to exhibit quantum confinement. Quantum confinement results when the electrons in a material are confined to a very small volume. Quantum confinement is size and shape dependent, meaning the properties of the nanoparticles are tunable based on their size and shape. Such nanoparticles may have applications in opto-electronic devices, laser diodes, nanosensing, and biomedical imaging. However, there remains a need for a method to synthesize semiconductor compounds in other nanostructure architectures that may exhibit quantum confinement.

This patent is subject to a terminal disclaimer.

Tuning and synthesis of semiconductor nanostructures by mechanical compression


A semiconductor memory enabling a read modify write operation of data, comprising: a memory cell array including a plurality of memory cells arranged in a matrix and able to be written with and read out data; a read address decoding means for independently decoding an address of a read memory cell in response to a read address; a write address decoding means for independently decoding an address of a write memory cell in response to a write address; a data reading means for reading data of a memory cell addressed by the read address decoding means; a data writing means for writing data to a memory cell addressed by the write address decoding means; and an address delay means by which a write address decoded by the write address decoding means is delayed by a predetermined time from a read address decoded by the read address decoding means, wherein the predetermined time is set as a predetermined plurality of times of basic synchronization pulse periods so that the data read modify write operation is accomplished in a pipeline manner by the basic synchronized pulse.

1. Field of the Invention
The present invention relates to a semiconductor memory device capable of performing a high speed read modify write (hereinafter referred to as an "RMW") operation aimed at a z-buffer for performing hidden-surface processing in the field for example of three dimensional computer graphics (hereinafter referred to as "3DCG").
2. Description of the Related Art
In recent years, high speed, large capacity memories, for example, a clock synchronization (synchronous) dynamic random access memories (DRAM) and a run-bus specification type have appeared.
Further, the field of 3DCG is rapidly spreading due to the improvement of the performances of personal computers, family computer game machines, etc. on the one hand and demands for higher speed and larger capacity memory than the past as the image memory for 3DCG.
For one application of an image memory, there are a frame buffer for storing drawing data and a z-buffer for storing a z-coordinate necessary for performing the hidden-surface processing indispensable for 3DCG.
In hidden-surface processing, polygonal drawing information referred to as polygons is generated. The size of the z-coordinate is compared with the periphery to calculate whether the polygon exists before or after other polygons, and processing of a drawing image is carried out by the polygons existing before the other polygon.
Accordingly, in the z-buffer for storing the z-coordinate, it is necessary to read the z-address of each polygon and perform the write modification after comparison with the other z-address. The operation thereof is basically an RMW operation.
FIG. 1 is a block diagram of a related art clock synchronization type memory.
In the figure, reference numeral 20 denotes a memory array, 22 an address decoder, 24 a register for temporarily holding an input signal of the address decoder 22, 26 an input buffer, and 28 an output buffer. Further, ADD represents an address signal, R/W-Data represents input/output data, and OE-cnt. represents an output control signal.
At present, in a generally commercially available general purpose memory, the same terminals are used for input/output of the data to and from the memory array 20 for decreasing the number of pins of the package as shown in FIG. 1, and the input and output of the data is switched by an output control signal OE-cnt. Namely, the input buffer 26 and the output buffer 28 are connected in parallel in inverse directions. The output buffer 28 is not operated when there is no input of the output control signal OE-cnt.
FIG. 2 is a flowchart of the operation when making general purpose memory perform an RMW operation for performing the hidden-surface processing of 3DCG.
In the figure, symbols A0, A1, denote address numbers in the memory array. The address signal ADD in the command is decoded (Ad-Dec) for every clock signal CLK with respect to the memory cell of this address number and output (D-out) after the stored data is read out (mem-R). After this data output, the z-address is subjected to the comparison processing in the next several clock sections, and the write modification to an original address in the memory is carried out. This RMW operation is continuously repeated in units of several addresses while shifting each address by one pulse each by the clock signal CLK.
In actuality, about three clocks are enough for the comparison processing per se, but in this illustrated example, continuous processing is carried out in units of six addresses. Further, as described above, it is necessary to use the same terminals for input/output, shift the output buffer 28 to the non-operating state by the output control signal OE-cot. at the switching thereof, and guarantee a high input impedance, therefore eight clock sections are required until the write modification from the data output is carried out in each address. For this reason, when viewing this from the command, as illustrated, a waiting section (in this case, 4 clocks worth) becomes necessary in the period of from R5 to W0, and the efficiency of RMW is bad.
In order to shorten the waiting section of this command, it can be considered too to make the address unit to be continuously processed small and shorten the clock section until the write modification from the data output of each address is carried out, but the number of times of switching of the output buffer 28 will be increased by this. For this reason, there is a limit in also the shortening of the command waiting section, and the control becomes complex if the input/output terminal is frequently switched.
In order to avoid this command waiting time, as shown in FIG. 3, the commonly used input/output pin can be separated.
When this separated input/output type memory is used for the RMW operation, as shown in the timing chart of FIG. 4, the waiting section of a command can be eliminated.
In a memory having the configuration shown in FIG. 3, it suffers from the disadvantage that the number of pins is increased, thus it was not practical, but a great increase of the bit width has become possible by the memory/logic mixing process in recent years, therefore the efficiency of the RMW can be enhanced to a certain extent by using this type of memory.
However, even if this method is adopted, as shown in FIG. 4, the input of the address signal is made common at the time of reading and writing of the data so as to suppress an increase in the number of pins, therefore the read/write operation of data still takes two clock sections and, thus, in this meaning, it does not lead to a drastic enhancement of efficiency of a RMW.
Namely, when it is desired to further improve the drawing performance of 3DCG, the fact that a plurality of clock sections are required for every read/write operation of the data becomes a major obstacle.

Method and circuit for enabling a clock-synchronized read-modify-write operation on a memory array


A modular power reclining chair is disclosed which includes a unibody chair frame supported on a power base assembly. A power-assisted linear drive mechanism is operably coupled to an actuation mechanism of the reclining chair to provide power assistance in positioning of a leg rest assembly, a tilt control mechanism and a swing linkage mechanism for moving the reclining chair through its various ranges of motion.

The present invention relates generally to reclining chairs and more particularly to a modular reclining chair having a power-assisted linear drive mechanism operably coupled to an actuation mechanism for positioning a leg rest assembly between extended and retracted positions, for tilting a chair frame relative to the base assembly, and for positioning a seat assembly between upright and reclined positions.
Recent developments in the design and fabrication of various articles of furniture, and in particular reclining chairs, has resulted in the replacement of the "chair within a chair" design by the integrated chair design. The integrated or "knock down" construction of a reclining chair utilizes unique fabrication and assembly techniques which effectively result in increased production efficiency and cost savings while concomitantly producing a high-quality article of furniture. In general, the construction of these integrated reclining chairs is such that a preassembled actuation mechanism is integrated into various frame components which, when assembled, are rigidly interconnected to define a "unibody" chair frame. In this manner, the conventional construction of supporting the actuation mechanism within a separate and distinct frame assembly is no longer required.
The actuation mechanism includes a drive rod and a front support shaft which are supported by and suspended between left and right side frame assemblies. Front and rear frame rail members interconnect the left and right side frame assemblies to define a rigid unibody chair frame which minimizes side-to-side movement of the actuation mechanism suspended therein, as well as lateral flexion of the side assemblies themselves. A major benefit of the "knock-down" assembly can be found in its ability to manufacture a wide variety of reclining-type chairs. The actuation mechanism further includes various mechanisms which relatively position components of the chair to provide certain comfort features. These mechanisms include a pantograph linkage mechanism for positioning a leg rest assembly, a swing linkage mechanism for positioning a seat assembly, and a tilt control mechanism for position the chair frame relative to a base assembly.
There have also been recent developments in power-assisted chairs which include a motor-operated drive mechanism for permitting a seated occupant to actuate the leg rest assembly, to tilt the chair frame relative to the base assembly, and/or to recline the seat assembly between an upright and fully reclined position. However, such chairs generally require the use of multiple motors for driving the separate linkage mechanisms associated with these motion features, thereby resulting in extremely large, heavy and expensive chairs. As such, power reclining chairs have, in the past, typically been targeted for very specific applications, such as to aid those persons needing assistance entering/exiting and operating the chair. Thus, there is a need for a reclining chair which combines the improved structure of a unibody chair frame with a power-assisted reclining mechanism, thereby providing a high-quality, affordable article of furniture.


The present invention discloses a hinge structure with changeable frictional faces, comprising a spindle socketingly disposed with a first enclosing part and a second enclosing part with the openings of the first and second enclosing parts pointing to the same direction to change the frictional face for torsion from the second enclosing face to the first enclosing part and thus to extend the service life and further to form a frictional face with four steps of different torsions to meet the demands of customers.

"Hinge Structure (11)," developed by the present inventor, is disclosed in the ROC Patent No. M304197 on Jan. 1, 2007. The invention mainly involves disposing two oppositely arranged sheathing parts (2) onto the shaft-connecting part (1), and when the two sheathing parts (2) rotate jointly with the shaft (11), the torsion difference generated by a bushing (2) with respect to the shaft (11) can be balanced by the torsion difference generated by the other oppositely arranged sheathing part (2) with respect to the shaft (11), such that the balance of torsion can be maintained.
In a conventional art, when the shaft-connecting part (1) is in rotation, the two sheathing parts (2) should form frictional faces for joint rotation on the shaft (11). If the frictional face can be replaced, the hinge structure's service life can be extended. Consequently, there is still room for improvement in the design of hinge devices.

Hinge structure with changeable frictional faces


Disclosed is a metal post filter assembly, of a millimeter wave band, using an NRD guide. A filter to which an electromagnetic wave travels is disposed in a filter housing which includes parallel conductive plates facing each other. The filter forms a plurality of inserting holes, by segmenting them into multi-stages, along the length direction of side surface of a dielectric line and parallel to the parallel conductive plates. The filter has a structure that multi-staged dielectric resonators are formed in a single body by inserting metal posts which provide discontinuous surfaces which cause a reflection with respect to the electromagnetic wave in each of the inserting holes. Each impedance of the multi-staged dielectric resonators has an impedance coupling relationship that the impedance becomes gradually and symmetrically smaller to both end stages. According to the impedance coupling relationship, a reflection amount of, and a transmission amount of, the electromagnetic wave traveling along the filter are properly determined. As a result, the filter provides a filtering function which selectively passes only a certain frequency band of the electromagnetic wave. The filter assembly is suitable for a commercial use due to its simple structure, a small loss and superiority in processing, assembly and productivity.

1. Field of the Invention
The present invention relates to a filter in a millimeter wave band, and more particularly to a millimeter wave band filter to which the technology of a non-radiative dielectric waveguide (xe2x80x9cNRD guidexe2x80x9d) is applied.
2. Description of Prior Art
An NRD guide circuit has attracted attention as a transmission line for a micro wave band, particularly a millimeter wave band above 30 GHz, due to its small transmission loss in comparison with a microstrip line and due to its easiness in manufacturing the transmission line in comparison with prior waveguides.
The structure of a general prior NRD guide circuit is illustrated in FIG. 1. The NRD guide circuit has a structure that a dielectric line 10 through which an electromagnetic wave is transmitted is sandwiched between two parallel conductive plates 12a, 12b made from conductive metal. A space h of the two parallel plates 12a, 12b is less than half a free space wavelength of a using frequency. Accordingly, the electromagnetic wave is blocked in places other than the dielectric line 10 and its radiation is restricted, so that the NRD guide circuit can transmit the electromagnetic wave along the dielectric line 10 at a small loss. Paying attention to such transmission superiority of the NRD guide circuit, there have been proposed NRD guide filters of the 35 GHz and 50 GHz bands.
FIGS. 2 and 3 illustrate the structure of a prior air gap coupled filter using an NRD guide. The prior air gap coupled filter has a structure that multi-staged dielectric blocks are sandwiched between the parallel conductive plates 12a, 12b. One dielectric line is cut into multiple dielectric blocks with proper lengths. The dielectric blocks 14axcx9c14e are straight aligned, with maintaining certain gaps therebetween, in the direction to which a signal proceeds and is air gap coupled with dielectric lines 10a, 10b on input and output sides, respectively. Each of the dielectric blocks operates as a dielectric resonator at each stage of the filter. The number of the dielectric resonator blocks is proportional to an order number of the filter. The air gap coupled filter shown in FIG. 2 is the fifth order filter because it has five dielectric resonator blocks 14axcx9c14e.
The typical raw material for the dielectric line of the NRD guide which is applicable to millimeter waves is teflon. Teflon has an advantage that transmission loss is small whereas it has such disadvantages arising from its material characteristic that its processing is difficult due to its weakness and that its assembly is difficult because it does not easily adhere to other materials like metal. These disadvantages are the reason why the NRD guide has not been commercially used since the first introduction by Professor Yoneyama in the early 1980""s.
Since the using frequency is as high as the millimeter wave band, a wavelength of the electromagnetic wave transmitted along the dielectric resonator blocks in the waveguide, i.e., within the parallel conductive plates, is very short. The characteristic of the filter, in this case, is sensitively changed in accordance with the physical dimensions of structural bodies and fixtures for setting the resonator. Thus, it is necessary not only that a length of each of the dielectric resonator blocks 14axcx9c14e should be so accurately calculated as to be resonated at a certain frequency within a passing band, but also that each of the dielectric resonator blocks should be made as precisely as a predetermined length to obtain a wanted characteristic of the filter.
Further, each of the multi-staged dielectric resonator blocks 14axcx9c14e should be spaced to maintain a proper gap apart from its adjacent dielectric resonator blocks. This gap should be determined to obtain an optimal impedance matching between the two adjacent resonator blocks. That is, in order to obtain a good characteristic of a designed filter, there should be a precision of several microns not only in the length of each of the dielectric resonator blocks 14axcx9c14e but also in the distance between the resonators.
However, in manufacturing the prior air gap coupled filter using the NRD guide, it is difficult to make the dielectric resonator blocks 14axcx9c14e have such a precision. And also, with maintaining the precision of several microns, it is difficult to align the dielectric resonator blocks 14axcx9c14e which have different lengths in a straight line in the direction that a wave proceeds. In doing so, a lot of time and labor are required. Due to these reasons, the prior air gap coupled filter is a disadvantageous structure in terms of making, assembly and production, and is not suitable for a commercial model which is applicable to a high frequency in the millimeter wave band.
That is, in the case of the prior NRD guide air gap coupled filter, the resonator of each stage exists as a single independent block having a different length from one another, and has a structure that an impedance of each stage is controlled by adjusting a distance between each resonator. In this kind of structure, it is difficult to precisely make the dielectric resonators and to align the independent block of each stage in the right position within the filter housing with maintaining a predetermined distance.
In order to improve the above problems, an object of the present invention is to provide a metal post filter assembly, using an NRD guide, which is designed for an easy making and a good productivity resulting from a convenient and accurate assembly and is capable of stably having filter characteristics to a wanted degree.
To accomplish the object of the present invention, there is provided a metal post filter assembly using a non-radiative dielectric waveguide, comprising: a filter housing which includes parallel conductive plates facing each other; and a filter, disposed between said parallel conductive plates, for filtering a certain frequency band of a traveling electromagnetic wave, said filter including, a single body type dielectric line, made from a non-radiative dielectric, whose side surface is formed with a plurality of inserting holes running parallel to said parallel conductive plates, said dielectric line being segmented into multi-stages by one or more sets of said inserting holes which are spaced apart by a predetermined distance along a length direction of said dielectric line, and the number of the sets corresponding to a filtering order of said filter assembly, and a plurality of metal posts, each of which having a diameter to be fittingly inserted in each of said inserting holes.
The filter is formed with multi-staged dielectric resonators cascaded as a single body and segmented by said metal posts, said multi-staged dielectric resonators providing a filtering function which selectively allows only the certain frequency band of the traveling electromagnetic wave to pass therethrough by a predetermined impedance coupling relationship. It is particularly preferable that an impedance of said multi-staged dielectric resonators is largest in a middle stage and becomes gradually and symmetrically smaller to both end stages. Further, it is preferable that a length of said multi-staged dielectric resonators is longest in a middle stage and becomes gradually and symmetrically shorter to both end stages.
According to one preferred embodiment of the filter, one inserting hole is formed per each stage on the side surface of said dielectric line, said inserting hole in each stage having a diameter which is largest in the middle stage and becomes gradually and symmetrically smaller to both end stages and being disposed along an approximately half-height of said side surface in line.
According to another preferred embodiment of the filter, two inserting holes whose diameters are identical are disposed, per each stage, above and below an approximately half-height point of said side surface of said dielectric line and a vertical distance of said two inserting holes in each stage is narrowest in the middle stage and becomes gradually and symmetrically wider to both end stages.
According to a third preferred embodiment of the filter, one or more inserting holes are formed per each stage on said dielectric line, the number of, and diameters of, the inserting holes in each stage being determined in the manner that a reflection rate in each stage against the electromagnetic wave traveling through said dielectric line is highest in the middle stage and becomes gradually and symmetrically lower to both end stages.
The metal window filter assembly further comprises a plurality of tuning screws inserted, parallel to said metal posts toward said dielectric line, through both side walls of said filter housing, for tuning a resonance frequency of the filter by adjusting insertion lengths of said tuning screws.
According to the metal post filter of the present invention, the filter can be made by forming the inserting holes in the dielectric line made from a material which is difficult for being processed, and the dielectric resonators having the desired number of stages can be made as a single body by inserting the metal posts in the inserting holes. And also, the filter assembly is easily assembled by inserting the filter between the upper and lower conductive plates of the filter housing.
Therefore, the filter assembly according to the present invention can remarkably maximize production efficiency and reduce manufacturing costs due to its simple structure and superiority in the processing and assembling thereof. Further, since the filter assembly of the present invention is designed to minimize the factors of error occurrence during its assembly, it has advantages of maintaining the precision of the processing machine for the filter structure of the millimeter wave band which requires the precision of several microns and of accurately maintaining the characteristic of the filter to the designed level as it can be assembled without an extra auxiliary zig.
Other characteristics and advantages of the present invention will become more apparent by describing in detail preferred embodiments thereof with reference to the accompanying drawings.

Metal post filter assembly using non-radiative dielectric waveguide


There is provided a head control apparatus that controls the flying height of a head with respect to a disk by controlling heater current supplied to a heater for head protrusion adjustment. The head control apparatus includes: an acquisition section that acquires flying height information which is information concerning a variation in the flying height of the head; a determination section that determines whether the flying height variation is caused by a variation in atmospheric pressure based on a measured temperature and the flying height information acquired by the acquisition section; and a control section that controls, in the case where the determination section has determined that the flying height variation is caused by a variation in atmospheric pressure, heater current based on control information corresponding to the flying height variation caused by the atmospheric pressure variation.

With a recent reduction in size and an increase in capacity, a magnetic disk apparatus has become available for portable use and, accordingly, resistance to environmental conditions such as vibration and impact, temperature, and atmospheric pressure is required to be improved.
In order to increase a mechanical strength of a magnetic disk apparatus under a reduced pressure, conventionally the air-bearing shape of a slider has been improved or parameters of a suspension spring pressure have been optimized.
Further, in recent years, as a technique for responding to a reduction in the flying height of a head, there is available a technique of setting the flying height to a desired height by using a heater provided near a read/write element positioned at the end of a head slider.
As a conventional art relating to the present invention, there are known the following apparatuses: a control apparatus that checks a change in the flying height caused due to a difference in atmospheric pressure by detecting a data error rate to thereby control a heater; a magnetic recording apparatus that controls the flying height in association with temperature; and a magnetic recording apparatus that checks an abnormal flying height by detecting the output of a head (refer, e.g., to Patent Document 1: Japanese Laid-open Patent Publication No. 2007-310957, Patent Document 2: Japanese Laid-open Patent Publication No. 2005-158088, and Patent Document 3: Japanese Laid-open Patent Publication No. 2005-141798).
With an enlargement of application of a magnetic disk apparatus, the level of a market demand in terms of a reduced pressure condition has become higher. Concretely, reduced pressure condition corresponding to an altitude of 4000 m to 5000 m class (conventionally, 3000 m) is required. Therefore, the reduced pressure resistance of a magnetic disk apparatus needs to be improved. Further, at the same time, with an increase in recording density of the magnetic disk apparatus, the flying height of a head slider needs to be reduced. Considering production variations including relative height between the slider and disk or disk flatness, it has become difficult to respond to a change in the flying height caused due to a reduction in pressure by improving the air-bearing shape of the slider.
Further, in order to ensure reliability of the magnetic disk apparatus, a crucial failure such as occurrence of scratches on the surface of a disk or occurrence of stiction between the head and disk due to a reduction in the flying height of the slider under a reduced pressure needs to be avoided.

Head control apparatus, head control method, and magnetic disk apparatus


The use of inorganic additives such as mica in the polyolefin layer of paper polyolefin paper laminates improves the electrical characteristics, gives resistance to discharge, and facilitates reduction of swelling in contact with oil. Accordingly, the present invention provides laminated paper polyolefin paper composites comprising first and second fiber paper layers, and a polyolefin layer comprising an inorganic additive such as mica.

The present invention relates to laminated paper polyolefin paper composites used in high voltage cables. These composites are formed by bonding together fiber paper layers of paper grade cellulose and a polyolefin layer. The invention relates more specifically to composites which have increased discharge resistance and which swell less than conventional composites when contacted with insulating oils.
Polyolefin laminate paper has good dielectric characteristic and high dielectric strength. Therefore, it is often used as an insulating material for high voltage or extra high voltage cables. However, various difficulties are present in conventional polyolefin laminates which prevent their use as replacements for more common paper insulation for transmission cable applications. One of these difficulties is the occurrence of partial discharges when there are flaws or air spaces in the laminates. Another difficulty is the swelling of the polyolefin layer which occurs when it is contacted with insulating oils. This swelling causes the tape not to slide and therefore wrinkle; it also leads to a reduction in dielectric strength of the polypropylene.
Various methods have been used to attempt to provide a superior laminated insulation construction. A first method is an "annealing method" where a cable, after taping, is subjected to a heat treatment carried out in a vacuum at a temperature lower than the melting point of polyolefin for a predetermined period of time to increase the degree of crystallinity of the polyolefin film, and thereby decrease swelling in the insulating oil. A second method is a "humidity adjusting method" where the paper layers are caused to absorb moisture to expand in advance; the decrease in thickness of the paper layers caused by drying after the taping operation is utilized to counter the increase in thickness of the polyolefin film layer which is caused by the swelling. A third method is an "after-embossing method" in which a paper polyolefin laminate is embossed so that irregularities are mechanically formed thereon. Deformation of these irregularities absorbs the increase in thickness of the polyolefin layer when it is swelled in the insulating oil. A fourth method is a "pre-embossing method" in which the paper layers are embossed prior to lamination.
It is an object of the present invention to provide laminate paper polyolefin paper composites which are discharge-resistant.
It is a further object of the present invention to provide laminate paper polyolefin paper composites which exhibit reduced swelling on contact with insulating oils.
Methods for making the above-referenced composites are also provided as yet a further object of this invention.
It is yet a further object of the present invention to provide high voltage cables with improved discharge-resistance and swelling characteristics. This in turn will lead to longer life and greater reliability.

Laminated paper polyolefin paper composite


A method for network analysis in an access network (1) in connection with a data transmission network, in particular an xDSL network, with a plurality of subscriber lines (4.1-4.3). The method comprising the step of collecting data on physical layer operational parameters ({φoi}) of at least one subscriber line (4.1-4.3) and the steps of simulating a behavior of higher network layers based on said collected data when deploying at least one application (6.1-6.3) on said subscriber line (4.1-4.3); generating data on higher layer performance parameters for said application (6.1-6.3); and generating an advice signal (AS) based on said data and indicative of the compatibility of the physical layer/application couple with predetermined Quality-of-Service (QoS) requirements for said application (6.1-6.3). Thus, the proposed method provides network operators with information concerning the question if a given service application (6.1-6.3) will run on a respective data transmission (core and access) network (1, 1′) in accordance with the QoS values recommended for said application (6.1-6.3), in particular a high-bandwidth rich media service type application, e.g. a triple-play service.

The invention is based on a priority application EP05291927.1 which is hereby incorporated by reference.
The invention relates to a method for network analysis in an access network in connection with a data transmission network, in particular an xDSL network, with a plurality of subscriber lines, the method comprising the step of collecting data on physical layer operational parameters of at least one subscriber line.
The invention also relates to a network analyser module for an access network in connection with a data transmission network, in particular an xDSL network, with a plurality of subscriber lines, the network analyser module comprising means for collecting data on physical layer operational parameters of at least one subscriber line.
Additionally, the invention relates to an xDSL network analyser, an integrated circuit, and an access multiplexer linecard comprising an inventive network analyser module, as well as to a computer program product for network analysis being operable to translate the inventive method into practise.
Due to the fast introduction and spreading of broadband technologies as well as in response to increased competitive pressure and consumer demands, a great number of new applications in the field of rich media services, e.g. delivery of video, VoIP (voice over IP), or gaming, are being developed. Other services of this kind are referred to as triple-play services (voice, video, and data), and require stable high-quality broadband connections—in addition to an overall increased bandwidth—for effective and reliable service delivery over data transmission (or communications) networks, such as a DSL and ADSL networks. In this context, the performance of a communication system is usually expressed in terms of QoS (Quality of Service). Depending upon the communication system in question, QoS may relate to service performance, SNR (Signal to Noise Ratio), BER (Bit Error Ratio), throughput rate, reliability, priority, delay, packet loss, number of visual disturbances per hour and other factors specific to each service. QoS is of particular concern for the continuous transmission of the above-mentioned high-bandwidth video and multimedia information, and can be measured in terms of an average delay, losses of transmission units (bits, cells, frames, or packets), or a transmission error rate, for instance. However, the network operators generally do not know if a newly developed application will run on their network (core and access) with the recommended QoS values. Furthermore, it is generally not possible for them to determine the error rate at the level of the application, e.g. video, VoIP, gaming, etc.
DLM (Dynamic Line Management) is a known prior art approach which is aimed at maximising data rates and maintaining quality and stability in communications networks (cf. ALCATEL Technology White Paper "Dynamic Line Management for Digital Subscriber Lines"). DLM allows switching of user/service profiles based on physical layer measurements of the MTBE (Mean Time Between Error Events) or MTBR (Mean Time Between (spontaneous) Resynchronisations). To this end, operational data is collected in order to determine physical line conditions during operation of the network in a non-stationary noise environment. Lines that are identified as stable are then assigned profiles with the highest bit rates possible, based on the physical quality of the line. In accordance with the measurement of physical layer operational parameters, a DLM module will switch a given line to a different profile in an attempt to offer a higher bit rate, ensure improved quality and stability, or reduce crosstalk owing to reduced transmit PSD (Power Spectral Density).
However, as only physical layer parameters are considered DLM does not provide a solution to the above-mentioned issue concerning the QoS requirements per type of application, e.g. delay, errors, etc.

Method for network analysis and network analyser module


Methods and apparatus, including computer program products, for protecting colors from being clipped during color adjustment. A first set of colors is identified in a source color space, and a first color mapping is specified to associate colors in the source color space with mapped colors. The first set of colors and the first color mapping are used to construct a third color mapping that can be represented as a concatenation of an injective second color mapping with the first color mapping. The third color mapping is constructed such that each color in the first set of colors is associated with a mapped color inside a destination color space.

The present invention relates to adjusting colors in digital images.
In a digital image, colors are represented by a set of color components of a color space. Examples of color spaces include RGB colors using red, green, and blue ("RGB") components; CMYK colors using cyan, magenta, yellow, and black ("CMYK") components; or Lab colors using scientifically defined components. A color space is typically finite and restricted to a representable range of values in each color component. For example, an RGB color space can be represented by a "cube" where each component has a value between 0.0 and 1.0.
Colors in digital images can be adjusted by using computer based technologies, such as the Adobe® Photoshop® image editing software, available from Adobe Systems Incorporated of San Jose, Calif., to achieve coloring effects, corrections, or color matching in different images. For example, image contrast can be increased by "stretching out" colors in a limited region to a larger region in a color space that represents colors in the image. Similarly, the image contrast can be decreased by "compressing" a region in the color space. Alternatively, colors can be "cast," i.e., biased, to make an image, e.g., greener; inversely, a color cast in an image can be corrected or removed.
A color adjustment can be generated by a color mapping that associates colors in the image with mapped colors. Based on the associated mapped color, a color in the image can be adjusted, i.e., replaced with the mapped color, if the mapped color can be represented in the image. When a color mapping provides a mapped color that is outside of the color space, e.g., a RGB component is out of the available range of 0.0 to 1.0, the mapped color is typically "clipped" to a color within (e.g., at the boundary of) the color space. For example, a negative RGB value can be clipped to, i.e., replaced with, 0.0 due to the adjustment. As a result of the clipping, information may be lost in the adjusted image when originally distinct colors are clipped to the same color.


Integrated optical devices and methods of forming the same are disclosed. A method of forming an integrated optical device includes the following steps. A substrate is provided. The substrate includes, from bottom to top, a first semiconductor layer, an insulating layer and a second semiconductor layer. The second semiconductor layer is patterned to form a waveguide pattern. A surface smoothing treatment is performed to the waveguide pattern until a surface roughness Rz of the waveguide pattern is equal to or less than a desired value. A cladding layer is formed over the waveguide pattern.

Integrated optical devices such as waveguides are often used as components in integrated optical circuits, which integrate multiple photonic functions. The waveguides are used to confine and guide light from a first point to a second point of an integrated chip (IC) with minimal attenuation. Although the existing waveguide structures have been generally adequate for their intended purposes, they have not been entirely satisfactory in all respects.

Integrated optical devices and methos of forming the same

Taiwan Semiconductor Manufacturing Company, Ltd.


A graphics rendering and editing apparatus includes a rendering unit configured to render a graphic object, a position specifying unit configured to specify a pre-change position and a post-change position of an arbitrary point on the graphic object, an attribute specifying unit configured to specify a deformation attribute of the graphic object, the deformation attribute being related to how the graphic object is deformed as a position of the arbitrary point changes, and a deformation unit configured to deform, when the position specifying unit has specified the pre-change position and the post-change position the graphic object in accordance with the pre-change position, the post-change position, and the attribute specified by the attribute specifying unit.

1. Field of the Invention
The present invention relates to a graphic rendering and editing apparatus and method for deforming graphic objects.
2. Description of the Related Art
A graphic rendering and editing apparatus may execute a rendering program that may dispose a graphic object, set up the graphic object, and edit the individual object. The rendering program may include a program that creates a curve by adding curve-control points of, for example, a Bezier curve, to a straight line and a curve. The rendering program renders a curve by first creating a line, then adding curve-control points, and then setting weights representing influences of the curve-control points.
Japanese Patent Laid-Open No. 2002-63586 discloses an apparatus that creates a curve fitted to the shape of a graphic object, such as a circle or an ellipse. The apparatus creates the curve fitted to the graphic object by fixing one end of a straight line and dragging and moving another end so as to surround the graphic object. A desired curve can be created with a small number of steps when the desired curve is a part of an existing graphic object.
However, in the rendering program that renders a curve by adding curve-control points and setting weights for the curve-control points, the relationship between curved portions and the positions of curve-control points may be complicated. Therefore, in order to create a desired curve, a user has to perform a large number of input operations. Moreover, in order to create a curve with a plurality of inflection points, such as a wavy line, a user has to add control points for the inflection points, which also requires the user to perform a large number of input operations.
The apparatus described in Japanese Patent Laid-Open No. 2002-63586 creates a curve such that the curve surrounds and fits to a graphic object, and the user has to prepare many graphic objects when there are no existing objects available for rendering a target curve, which requires the user to perform a large number of input operations. Furthermore, in order to further curve a middle portion of a curve once created, a user has to set a fixed end in the curve and drag another end such that the curve surrounds and fits to a graphic object, which requires the user to drag the other end over a long distance.

Graphics rendering and editing apparatus and method


A coolant sealing structure for a solar cell of which the sealing property is maintained with high reliability in use for a long period. A solar cell has its light receiving surface and a reinforced portion formed around the fringe portion of the light receiving surface. The plate member is joined with the top of the reinforced portion by means of an anode joint process. A transparent member is joined with the plate member to form a coolant passage. This structure allows the solar cell to be directly cooled with the coolant flowing through the coolant passage. Since the solar cell is joined with the plate member, separation does not occur at the joined portion under repeated temperature changes. The coolant sealing structure can be used with high reliability for a long period.

1. Field of the Invention
The present invention relates to a solar battery, and more particularly to a solar battery cooling structure.
2. Description of the Related Art
Generally, a solar cell tends to have decreased power generation capability as its temperature rises. For example, when the temperature of a solar cell rises up to 100.degree. C., its power generation capability decreases by about 60% compared to that at 25.degree. C. Hence, various solar cell cooling techniques have been conventionally proposed to suppress a fall in power generation and to improve the durability. Such a solar cell cooling technique is disclosed in Japanese patent laid-open publication Hei 5-83881. This publication teaches the technique of immersing a solar cell element into water according to a cooling jacket system. In this example, a solar module is formed by arranging solar cells and then covering the intermediate product with a waterproof resin. Hence, it is considered that the solar cells are indirectly cooled via the resin.
However, in order to reduce energy recovering years or energy payback term (years in which the energy used for production of a solar module can be recovered as generated power) and to reduce the cost of building a solar-cell built-in power generating system, much attention has recently been focused on the light-gathering-type solar module that gathers the sunlight using a condenser, thus increasing the incident light amount on a solar cell and reducing the use area for expensive solar cells. In such a light-gathering solar module unit, since the temperature of the solar cell rises significantly with an increase of the light condensing degree, it is difficult to obtain a sufficient cooling effect in the conventional cooling method. In order to cool the solar cell effectively and efficiently, the solar cell may be directly cooled with a coolant. A technique of directly cooling a solar cell is shown in FIG. 5. Referring to FIG. 5, the solar cell 10 is formed on the substrate 100. The generated power is taken out of the electrodes 12 formed on the rear surface of the solar cell 10 via the bus lines 102. Bank-like reinforced portions 14 are formed around the fringe of the light receiving surface of the solar cell 10. The sealing agent 104 such as an epoxy resin seals surfaces ranging from the reinforced portion 14 to the substrate 100 and is filled in the gap between the solar cell 10 and the substrate 100. Even when the solar cell 10 is directly cooled with a coolant such as water, this sealing agent prevents the coolant from flowing onto the electrode 12. As a result, the electrode can be prevented from being corroded. However, when the solar cell is used for a long period of time, the solar cell 10 experiences repetitive changes in temperature. The difference in thermal expansion coefficient between silicon, or a material forming the solar cell 10, and the sealing agent 104 causes the sealing agent 104 to come away from the solar cell 10. It is considered that this coming away occurs when the solar cell is used for 2 to 6 years. For that reason, there is the problem in that the coolant is leaked from the interface between the solar cell 10 and the sealing agent 104 to the electrode 12, thus corroding the electrode 12.

Coolant sealing structure for a solar cell


A method of dry cleaning articles such as clothing and the like including the use of Dipropylene Glycol Monomethyl Etheracetate as the cleaning solvent and the use of vacuum to assist in the removal of solvent from the articles and the use of vacuum distillation of the solvent after a cleaning cycle.

I. Field of the Invention
This invention is in the general field of dry cleaning of clothing, other fabrics, and the like;
The invention is more particularly directed to a method for dry cleaning utilizing specially designed machinery and uniquely modified solvents and treatment cycles;
The invention is more particularly directed to a dry cleaning method wherein a solution is utilized which has the desirable and safe flash point rating and the fabric-safe qualities required, together with superior, specially designed dry cleaning machinery;
The invention, therefore, is most particularly directed to a totally new dry cleaning method.
II. Description of the Prior Art
The prior art in dry cleaning includes the use of various solvents with appropriate machinery to accomplish the cleaning. In the most recent past the solvent most widely used has been perchloroethylene ( hereafter generally referred to as "perc") Perc has the disadvantage that it is environmentally very destructive and undesirable. In some areas perc is no longer allowed to be used. Additionally, in the past other solvents such as petroleum based solvents and glycol esters, ethers, and acetates have been tried and used. These various solvents have been used with machinery which may not have been ideal.
The present invention is distinct from the prior art in that it relies upon a specially formulated solvent with unusual characteristics as described below, together with a specific method involving the use of specialized machinery designed specifically into a complete dry cleaning method.


An electronic device is configured to perform a method of previewing images photographed by a plurality of cameras. The method includes displaying a main preview image of a first one of the cameras, and displaying a sub preview image of a second one of the cameras in the main preview image; changing a property of the sub preview image in response to movement of the electronic device; and when the movement of the electronic device stops, restoring the changed property to an original property before the changing.

Generally, an electronic device such as a smart phone, a cellular phone, etc. has a camera, previews an image photographed by a camera to a user, and stores the image photographed by the camera in a memory in response to selecting of a shutter key of the electronic device by the user. The electronic device may have two or more cameras, and may operate in a multi-preview mode in which images corresponding to the cameras are previewed.

Method of performing previewing and electronic device for implementing the same


An Osteospermum cultivar particularly distinguished by purple and white inflorescences, an upright and medium-sized plant habit, and a freely branching and vigorous growth habit, is disclosed.

The present invention comprises a new and distinct cultivar of Osteospermum, botanically known as Osteospermum ecklonis Norl., and hereinafter referred to by the cultivar name 'Trad Purbilor'. The new cultivar originated from a hybridization made in June 1999. The female parent was the proprietary 'OY-85-6' (unpatented) Osteospermum plant, with light purple inflorescences, while the male parent was the proprietary 'OY-81-2' (unpatented) Osteospermum plant, with purple inflorescences. The seeds produced by the hybridization were sown in August 2003. A single plant selection was chosen for further evaluation and for asexual propagation in January 2004.
The new cultivar was created in 1999 in Andijk, The Netherlands, and has been asexually reproduced repeatedly by vegetative cuttings and tissue culture in Andijk, The Netherlands, Gilroy, Calif. and Hillscheid, Germany over a 2 and a half year period. The present invention has been found to retain its distinctive characteristics through successive asexual propagations.
Plant Breeder's Rights for this cultivar have been applied for in Canada on Mar. 21, 2006 and in Switzerland on Nov. 13, 2006.

Osteospermum plant named ‘Trad Purbilor’


The present invention relates, among other things, to a method for forming a workpiece (240) of a material having an exponential tensile stress-strain behavior into a thin-walled, hollow shell (243). In this method, the workpiece (240) is clamped on its periphery and is actively rotated about its center line (M). A freely rotatable spinning die (4) having an external side (4a) with the desired shell shape (243) is pressed with a suitable pressure force against a workpiece side (24a). At least one path-controlled spinning roller (14, 17) is pressed against the other workpiece side (24b) so that the rotating workpiece (240) is formed into shell (243) exclusively by the local pressure forces, the relative velocity between the workpiece (240) and the at least one spinning roller (14, 17) and the force exerted on the workpiece (240) by the at least one spinning roller (14, 17) and the spinning die (4) being matched to one another such that the pressure forces applied to the workpiece (240) are below the yield strength of the workpiece (240). In addition, the present invention relates to a device for carrying out the method. Moreover, the present invention relates to a method and a device for forming a workpiece of a material which was previously only formable at known hot-forming temperatures, but as a result of the present invention, is now able to be formed into a thin-walled, hollow shell at a temperature below the hot-forming temperature known for the material of the workpiece.

Workpieces of the aforementioned type exist for example in the form of round sheet metal blanks or sheet metal blanks which are only able to be formed into the desired shell shape in a complicated and thus expensive manner due to the indicated material properties. As a result of their low weight and good corrosion resistance, titanium and its alloys in particular are consequently used for fuel tanks and the like in the aviation and aerospace industries. However, the titanium-β alloys which are particularly suitable for this purpose are difficult to use in a cold-forming process. These alloys namely have an exponential tensile stress-strain behaviour. It is fundamentally only possible to form such materials into thin shells, in particular into a hemispherical shell, or into a hemisphere-like shell shape via pressure forming since the high-strength, light materials and their corresponding properties would otherwise be damaged. Such methods are also referred to as net-shape methods.
In general, EP 0 457 358 A2 describes a method and a device for metal spinning. It proposes clamping a blank of difficult to form material at the periphery and using a motion-controlled spinning tool 3 to curve it freely, i.e., without the use of a spinning chuck, into a free space to the final dimensions. A similar method and device are known from U.S. Pat. No. 3,342,051 in which forming without the use of a spinning chuck is also described. DE-OS 1 527 973 also teaches a similar method for producing surfaces of revolution without the use of a spinning die.
GB 2 302 832 A describes a method and device for metal shaping. In this known method, a blank is held by a centrally situated counterpunch on a rotating spinning die. The blank is formed via a spinning roller which follows a certain contour and forms the blank according to the shape. Such a method is not usable for forming materials of the type recited at the outset having a particularly high material tensile strength.
EP 0 593 799 B1 describes the forming of workpieces from the indicated materials. In particular, the specific forming problems are discussed in detail. In addition, the problems of other forming methods in the case of workpieces of the indicated materials are elucidated in detail. EP 0 593 799 B1 and parallel U.S. Pat. No. 5,426,964 teach a simpler and more cost-effective method for cold forming a material having an exponential tensile stress-strain behaviour into hollow shells having a low wall thickness. As a result, a sheet metal blank is clamped on the periphery and is rotated about its centre line via a drive. The rotating sheet metal blank is formed between a first and a second path-controlled spinning roller acting on opposite sides of the sheet metal blank and is cold-formed into a shell solely by local pressure forces. The relative velocity between the workpiece and spinning rollers and the force exerted by the spinning rollers on the workpiece are matched to one another such that tension forces applied to the workpiece are less than the yield strength of the material. According to this proposed method, the material is namely not exposed to any tension forces in the plastic area and the material is formed exclusively by pressure forces exerted on the workpiece by the two opposing spinning rollers.
This proposed method renders it possible to use cold forming to produce hollow shells having a large diameter and a relatively thin wall thickness to the final dimension without fatigue cracks or bulges being able to be detected and without occurrence of the problems resulting from heating of the material. A reason for this is that the achievable high cold-forming degree effects a grain refinement in the structure of the titanium-β alloy which then results in high strength and toughness so that the supporting cross section and thus the weight are able to be further reduced. In addition, the high cold forming degree in the peripheral direction results in a change in the texture of the original rolling direction of the cold-rolled sheet metal blank so that the risk of distortion due to residual stress associated with this texture is reduced. The pressure forces to be exerted via the spinning rollers are able to be regulated very precisely so that shells having a constant wall thickness as well as having a wall thickness varying over the periphery of the shell may be readily produced. As a result of the use of spinning rollers opposite one another, the occurring springback may be controlled so precisely that shells having very high dimensional accuracy are able to be produced. However, many "forming passes" may be necessary to achieve the desired shell shape, thereby making the method time-intensive and consequently also entailing relatively high manufacturing costs. It should be noted here that in this case the term "forming pass or forming steps" refers to the moving or passing through of a spinning roller from its starting position (in the area of the centre line of the workpiece to be formed) to its end position (near the periphery edge of the workpiece).
Finally for the sake of completeness, U.S. Pat. No. 3,248,918 is mentioned here. It describes a method for forming reflectors. In this method spherically formed metal reflectors are to be produced without a die which is referred to as expensive. In this case a flat circular blank of a metallic, radiation reflective material is clamped by a clamping means. The clamped sheet metal blank is rotated in order to bend the outer edge over. The thus pre-formed sheet metal blank is then secured again via other clamping means, is rotated again, and is then formed into the desired shaped. Forming special materials of the type recited at the outset having an exponential tensile stress-strain behaviour is obviously not possible using this method.

Method and device for deforming a workpiece made of a material having an exponential tensile stress-strain behavior into a thin-walled, hollow shell


An embodiment provides a method for measuring a flow of a fluid using a magnetic flow sensor, including: introducing a magnetic flow sensor into a fluid, wherein the fluid has a flow path, wherein the magnetic flow sensor comprises a coil and metallic field disrupter; positioning the magnetic flow sensor such that a distal end of the magnetic flow sensor is parallel with the flow path of the fluid; and measuring a flow of the fluid by measuring a voltage received from the magnetic flow sensor. Other aspects are described and claimed.

Magnetic flow sensors or magnetic flow meter may measure a fluid flow. The fluid flow may be measured by a voltage. The voltage may be induced by a flow of a liquid through a magnetic field. Magnetic flow meters operate via magnetic induction. Magnetic flow meters operate when the fluid passing the sensor is conductive. For example, the conductive fluid may be water containing ions. A magnetic flow sensor may be placed in a flow of a conductive liquid. For example, the sensor may be placed in a pipe carrying the conductive fluid.


A seat assembly includes a seat and a headrest connected to the seat and movable between a first position and a second position with respect to the seat. The seat assembly also includes a biasing element biasing the headrest toward the second position. A releasable headrest restraining mechanism restrains the headrest in the first position when the seat is unoccupied and releases the headrest to permit movement of the headrest via the biasing element to the second position when the seat is occupied. A method of moving the headrest is also provided.

A seat assembly, such as a vehicle seat assembly, often includes a headrest connected to the seat. It is desirable to be able to move a vehicle headrest between a variety of positions for occupant comfort and for enhanced driver visibility. The art includes a variety of headrest positioning mechanisms.

Occupant detecting seat assembly with headrest and method of moving headrest