An intraoral mandibular advancement device to treat sleep disorders in a user having an obstructed airway includes a maxillary appliance with a main body for removable attachment to the maxillary teeth; a protrusive element distending from the central portion of the main body; and retention means extending from the main body for retention of the device on the maxillary teeth during sleep. A mandibular appliance removably attaches to the mandibular anterior teeth and includes a lingual spacer that extends posteriorly from the mandibular anterior teeth. The anterior aspect of the protrusive element of the maxillary appliance contacts the posterior edge of the lingual space and thereby causes mandibular advancement.

1. Field of the Invention
The present invention relates generally to devices for treatment of sleep disorders, and more particularly to an intraoral mandibular advancement device for the treatment of snoring, obstructive sleep apnea, gastroesophageal reflux disease, and bruxism and method for delivering the same.
2. Discussion of the Background
Among the health problems associated with sleep disorders are inter alia, snoring, gastroesophageal reflux disease ("GERD"), obstructive sleep apnea ("OSA"), bruxism, diabetes, high blood pressure (hypertension), and increased risk of stroke or heart attack.
The most widespread sleep disorder is snoring which is a common affliction that affects tens of millions of people worldwide, and can potentially have very serious health and social consequences. Snoring is a sound produced by the vibration of tissue caused by a breathing obstruction during sleep. There are many factors associated with snoring including, but not limited to: heredity, body weight, age, gender, smoking history, nasal, tonsil, or soft palate deformities, use of alcohol, allergies, and sleep position. Commonly, both the snorer and the snorer's sleep partner lose sleep due to the snorer's snoring. The sleep partner is awakened by the sounds caused by snoring, perhaps repeatedly each night. Movement by the sleep partner in subsequently attempting to fall back asleep may then awaken the snorer, if the noise of his or her own snoring has not already done so. Lack of sleep subsequently leads to daytime fatigue, a compromised immune system, poor mental and emotional health, irritability and lack of productivity, which can lead to further repercussions. Snoring is thus problematic for many people.
Obstructive sleep apnea is a potentially lethal sleep and breathing disorder defined as the cessation of breathing for 10 seconds or more (an apnea) at least five times per hour of sleep. In severe cases, individuals can wake up 300 times per night. When breathing is interrupted by an obstruction in the airway, the body reacts by waking enough to start breathing again. Arousals may occur hundreds of times each night, and may not fully awaken the individual, who remains otherwise unaware of the loud snoring, choking and gasping for air typically associated with OSA.
Although not all snorers have OSA, snoring is a cardinal symptom of OSA and clearly indicative of and associated therewith. Many OSA sufferers do not receive a sufficient amount of sleep due to repeated apneatic events and arousals which act to prevent REM and deep stage sleep, which can lead to chronic daytime exhaustion and long-term cardiovascular stress. OSA is the direct cause of at least 38,000 deaths each year. An estimated 30 million Americans suffer from some degree of OSA, yet less than 3% are currently undergoing any type of treatment.
Pathogenesis of OSA involves a combination of reduced upper airway size and altered upper airway muscle activity, which causes oral tissue to collapse, and hence a blockage to occur. Other factors which are thought to contribute to OSA include tongue size, soft palate volume, a retrognathic mandible, an anteroposterior discrepancy between the maxilla and the mandible, and obesity.
Snoring and OSA are often associated, as generally both are caused by blockage of the pharyngeal airway by, for example, excess tissue when various muscles of the body, including the tongue, relax. As the tongue relaxes, it moves posteriorly, blocking the breathing airway. When the breathing airway is blocked, exhaled air is forced through the airway with increased velocity thereby causing vibration of the tongue, tissue, or other obstruction, thereby creating noise. Snoring is caused by the partial obstruction of breathing during sleep while OSA occurs when the tongue and soft palate collapse onto the back of the throat and completely block the pharyngeal airway, thereby stopping breathing during sleep and restricting the flow of essential oxygen. Thus, a correlation between snoring and OSA is generally recognized in the medical community.
Many attempts have been made to reduce or eliminate snoring and OSA in individuals. Various types of surgery, including tracheostomy, surgery of the soft palate and oropharynx, and reconstructive surgery have been utilized in the treatment of snoring and OSA. Invasive surgery however is costly and not without risk, which effectively eliminates this modality as a truly viable solution to snoring and OSA for the general population. Indeed, many practitioners and patients alike would generally seek to avoid surgical intervention and would welcome a minimally invasive route—a general object and feature of the instant invention.
It has been recognized that opening or enlarging an airway that may be constricted due to collapse of tissue about the oropharynx will normalize the airflow to the lungs and in doing so will have a direct effect of resolving snoring and OSA as well as diminishing pressure fluctuations in the esophagus which have been associated with GERD. Known in the art are devices (heretofore cumbersome or ineffective) which are designed to restrict the velocity of the ingress and egress of air with the goal of reducing or eliminating snoring. It is scientifically concluded herein that by opening the aperture of the airway and maintaining the same, the consequences of a collapsed airway are avoided. When the airway is collapsed, the velocity of air flow increases and causes the vibration of the tongue, soft palate, and other tissue present in the pharyngeal wall during sleep. Thus, when expanded and maintained by the invention herein, the airflow is also maintained and snoring and OSA (where it theretofore resulted therefrom) are minimized or eliminated.
For example, U.S. Pat. No. 6,263,877 to Gall shows a device which essentially consists of a mouth guard with a small aperture for which are can pass through. The amount of air flow is therefore directly proportional to the size of the aperture. U.S. Pat. No. 5,642,738 to Lilly, Jr. shows a device which is designed to eliminate snoring via a membrane which is placed on the exterior surface of the anterior teeth to reduce the volume of air which is allowed to flow in and out of the mouth. U.S. Pat. No. 4,817,636 to Woods likewise shows a device which seeks to eliminate snoring via a membrane which is placed on the exterior surface of the anterior teeth to reduce the volume of air which is allowed to flow in and out of the mouth. Yet, reduction of airflow can cause a cascade of other symptomology and situations, including potential OSA.
Also known in the art are devices which seek to reduce or eliminate snoring or OSA by inhibiting vibration of the soft palate. For example, U.S. Pat. No. 6,467,485 to Schmidt shows a device made of a flexible material which is placed over the soft palate in an attempt to inhibit vibration of the soft palate. U.S. Pat. No. 4,669,459 to Spiewak shows an intraoral device which seeks to eliminate snoring by positioning a button on the soft palate to prevent vibration thereof. Yet, such devices do not address the source of the problem or intervene to increase the airway (as does the instant invention), and thus the cascade effect is still a present risk if such devices are employed.
Various devices have sought to alleviate snoring by aiming to keep the pharyngeal airway open to prevent the collapse of the tongue and soft tissues in the back of the throat, yet are bulky and uncomfortable, often resulting in reduced patient compliance. For example, U.S. Pat. No. 6,386,201 to Fard shows a pillow which seeks to keep the user's head in proper position to make snoring less likely. U.S. Pat. No. 4,366,815 to Broomes and U.S. Pat. No. 5,357,981 encompass other designs aimed at maintaining the user's body in a position which makes snoring less likely. U.S. Pat. No. 6,668,834 shows a device which seeks to eliminate or reduce snoring by maintaining the user's chin above the user's chest while in the supine position in order to facilitate breathing as well as to aid in the prevention of snoring.
Positioning of the body does not eliminate the cause of snoring. Since tongue posture appears to have a substantial effect on upper airway morphology, several devices show a design which seeks to hold the tongue in a forward position in order to increase the diameter of the pharyngeal airway during sleep. For example, U.S. Pat. No. 6,494,209 to Kulick shows a device which consists essentially of a mouthpiece with an anterior suction mechanism which creates a vacuum which acts to maintain the tongue in an anterior position. U.S. Pat. No. 6,408,851 shows a device which clamps the tongue in order to maintain the tongue in a forward position. U.S. Pat. No. 6,055,986 to Meade shows a device for the reduction of snoring which encompasses both upper and lower positions which together form a cavity which encompasses the user's tongue when in use to maintain the tongue in a predetermined position or to prevent the tongue from moving posteriorly and thus blocking the pharyngeal airway. U.S. Pat. No. 5,988,170 shows a snoring prevention apparatus consisting essentially of a mask having a tongue depressing member, which acts to maintain the tongue in an anterior position during use. U.S. Pat. No. 6,845,774 to Gaskell shows a mandibular splint which acts to maintain the user's jaws at a predetermined space apart to prevent the tongue from moving posteriorly in order to open the breathing passage. One can only image how truly uncomfortable such devices must be if used at all, and thus the likelihood of patient compliance is small to nil.
There is also recognition of those of ordinary skill in the art of a correlation between OSA and nocturnal gastroesophageal reflex disease ("GERD"). Both OSA and GERD involve a reduction in air pressure in the trachea and esophagus caused by blockage during sleeping, thereby resulting in an increase in the draw of pressure through the esophagus as the diaphragm distends. While the body tends to increase breathing by such distention, the blockage results in the pulling of fluid upwardly in the esophagus and hence results in GERD for the snorer or OSA patient. Yet, the currently recommended solutions involve some version of a "CPAP" (continuous positive airway pressure) or pharmacological intervention. The former involves a face mask and a pump to provide pressure directly to the trachea of the patient which is cumbersome and unaesthetic. The latter obviously includes a plethora of side effects associated with the pharmacology employed, while not directly addressing the physical/mechanical source of the problem.
It is herein recognized that advancing the mandible in an anterior position relative to the maxilla during sleep opens the pharyngeal airway by indirectly urging the tongue forward to stimulate activity of the muscles in the tongue and thereby also increases the forward rigidity of the tongue. Since the tongue attaches to the posterior portion of the mandibular symphysis, advancing the mandible forward relative to the maxilla also pulls the tongue forward, thus preventing the tongue from obstructing the pharyngeal airway. Since the palatoglossus muscle attaches from the tongue to the soft palate, resultant forward movement of the tongue thereby creates tension on the soft palate thereby reducing vibration. Mandibular advancement devices therefore function to move the lower jaw, and hence the tongue forward to open the oropharynx. Snoring thus decreases proportionally with the increase in airway size or diameter.
It should therefore be appreciated that by so urging, and as an object of the instant invention, there can be a positive effect on reduction of snoring and OSA, and also upon GERD which is associated with the existence of large intrapleural pressure swings, which occur during apneatic events.
A number of different appliances for the treatment of snoring or OSA which move the mandible forward relative to the maxilla have been suggested, yet such devices typically fit over both the arches of teeth and are thus large and cumbersome. Several such different devices allegedly for the treatment of snoring or OSA move the mandible forward relative to the maxilla can be observed in the following U.S. patents: Halstrom, U.S. Pat. No. 6,729,335; Thornton, U.S. Pat. No. 6,516,805; Orrico, U.S. Pat. No. 6,170,485; Belfer, U.S. Pat. No. 6,092,523; Bergersen, U.S. Pat. No. 6,129,084; Fenton, U.S. Pat. No. 5,499,633; Tomasi, U.S. Pat. No. 5,313,960; Hays, U.S. Pat. No. 5,277,202; Shapiro, U.S. Pat. No. 5,177,816; and Strong, U.S. Pat. No. 6,526,982. These devices consist essentially of acrylic or elastomeric upper and lower bite trays which fit over both the maxillary and mandibular teeth, respectively, with some connecting means to shift the user's bite so that the mandible is urged forward relative to the maxilla. Thus, to achieve anterior movement of the mandible, these devices essentially move one jaw against the other in a cumbersome manner which no doubt has an effect on patient compliance.
Such appliances which fit over both arches of teeth were derived from the orthodontic domain which it has ordinarily been considered prudent to cover all the teeth in order to prevent undesired movement (eruption) of any teeth not covered by the device resulting from a lack of opposition. Studies have shown however that partial coverage of the teeth during sleep does not result in undesired eruption of uncovered teeth, therefore rendering previous concerns unwarranted. These devices are therefore unnecessarily bulky and difficult to fit over the user's teeth. Bulky devices also occupy a large portion of the oropharyngeal volume, thus making breathing, and the passage of air around the bulky device difficult—the very antithesis of the goal herein sought: to increase the dimensional size of the airway. Breathing difficulty substantially reduces the efficacy of such devices to treat snoring or OSA, let alone the secondary effects of GERD caused by airway obstruction.
Many devices claimed for treatment of snoring or OSA which move the mandible forward relative to the maxilla fit over both the arches of teeth and also move one jaw substantially against the other, thereby posing other potentially damaging effects. Mandibular advancement devices that fit over both the maxillary and mandibular teeth are typically held nearly stationary, thereby restricting movement, causing discomfort, and potential permanent repositioning of the jaw. Since these types of devices restrict the user's natural lateral movements as well as anterior and posterior movements, continued use can potentially aggravate the tempromandibular joint (TMJ) and the related facial musculature, which would worsen over time, with continued use. Thus, it is an object of the instant invention to permit such movements, increase comfort and compliance, and additionally avoid TMJ effects.
Also shown in the art are appliances which are worn only upon the user's maxillary teeth, thus leaving the mandibular teeth uncovered. For example, U.S. Pat. No. 5,915,385 to Hakimi discloses a snore and stress relief device which seeks to engage the user's upper dentition and includes an anterior extension which appears to advance the user's lower jaw forward with respect to the user's upper jaw such that the user's upper airway is enlarged and the passage of air through the upper airway is facilitated. The device disclosed in Hakimi has a posterior position which fits against the dorsal surface of the user's soft palate to secure the device, which may also cause gagging or other discomfort, thus reducing or eliminating efficacy.
Although prior devices may have effect in treating snoring and OSA by moving the mandible forward relative to the maxilla to open the airway, such devices have unwanted side effects or are ineffective due to, inter alia, their bulk. As stated herein, many of the devices which appear to be designed to alleviate snoring and OSA restrict the user's natural nocturnal movements of the lower jaw which can potentially aggravate the tempromandibular joint and related jaw muscles and ligaments. Due to their bulk, devices prior to that shown herein that claim a design to eliminate or reduce snoring or OSA rely largely on the user's ability to breath through the nose. Thus, such devices would not function properly with users who have difficulty breathing through their noses. Furthermore, many of these devices must be removed or unhinged or otherwise disengaged to allow the user freedom to speak, swallow, or drink water, thus creating serious inconvenience to the user (and poor aesthetics). It is thus an object of the instant invention to overcome these shortcomings in prior devices.
Gastroesophageal reflex disease ("GERD"), also known as acid reflux, is a chronic condition which affects at lest 5 to 7% of the global population, including over seven (7) million people (reportedly as high as 30 million) in the United States alone. GERD is characterized by movement of the liquid contents of the stomach from the stomach into the esophagus. Almost everyone experiences gastroesophageal reflux at some time or another. When reflux is frequent or severe enough to cause more significant problems, it is characterized as GERD. GERD can cause serious complications including inflammation of the esophagus from stomach acid that causes bleeding or ulcers. Asthma, chronic cough, and pulmonary fibrosis may be aggravated or even caused by GERD.
The liquid content of the stomach typically contains acid, pepsin, and bile, which are harmful to the delicate lining of the esophagus when regurgitated. Damage to the esophageal lining can result in scarring and narrowing of the esophagus, and can be linked to the development of esophageal cancer.
Pressure created by the lower esophageal sphincter ("LES") and diaphragm surrounding the LES ordinarily create a barrier to reflux. During snoring or an apneatic event, however, a large negative intrapleural pressure swing often occurs facilitating reflex events. Thus, blockage of the esophageal airway creates a negative pressure which allows reflux to occur by facilitating the upward movement of the liquid contents of the stomach. When in an upright position, most refluxed liquid naturally flows back into the stomach due to the force of gravity. When in a supine position however, most refluxed liquid is forced upwardly, into the esophagus, typically causing damage thereto. Due to the increased potential for reflex during sleep in the supine position, it is therefore beneficial to have a method of treatment which can be applied during sleeping hours to maintain the pressure system without creating negative esophageal pressure and concomitant potential reflex. See, e.g., Green, B T, et al., Marked Improvement in Nocturnal Gastroesophageal Reflux in a Large Cohort of Patients with Obstructive Sleep Apnea with Continuous Positive Airway Pressure, Arch. Intern. Med., 2003 Jan. 13; 163(1):41-5.
Symptoms of gastroesophageal reflux disease include regurgitation, heartburn, difficulty swallowing, chest pain and nausea. As a chronic disease, treatment of gastroesophageal reflux disease typically continues indefinitely. It is therefore preferable that a method of treatment for gastroesophageal reflux disease is comfortable for nightly use.
Among the heretofore shown methods used to treat GERD are the use of antacids, histamine antagonists, proton pump inhibitors, promobility drugs which stimulate the muscles of the gastrointestinal tract, foam barriers which form a physical barrier to the reflux of liquid, and surgery. For example, U.S. Pat. No. 6,979,750 to Scanlan et al. shows thyronamine derivatives and analogs for the treatment of GERD. U.S. Pat. No. 6,974,837 to Jerussi et al. shows pharmaceutical compositions that comprise a racemic or optically pure sibutramine metabolite and a phosphodiesterase inhibitor for the treatment of GERD. U.S. Pat. No. 6,548,518 to Rubin et al. shows the use of norcisapride in combination with proton pump inhibitors or H2 receptor antagonists for the treatment of GERD.
Continuous Positive Airway Pressure ("CPAP") therapy has been shown to reduce GERD by increasing intra-esophageal pressure. Yet these devices have drawbacks, as herein stated, and thus are not of choice especially if non-invasive, easily placeable and removable, and not uncomfortable alternatives, like that of the instant invention, are available. Although there exists a broad range of dentally-retained intraoral appliances worn at night for the treatment of snoring and obstructive sleep apnea, no such appliances heretofore satisfied such criteria and, also, were directed at treatment of GERD. It is thus an object of the instant invention to present a noninvasive alternative to drug therapy and surgical intervention for the treatment of GERD.
Bruxism is the technical description for clenching, gnashing or grinding of teeth. Bruxing is common in almost all individuals and can occur subconsciously or when an individual becomes stresses or aggravated. The risk of bruxism increases with age, stress, and use of caffeine, nicotine and other drugs. In most cases, bruxism is mild and does not require treatment. When bruxing is more frequent however it can lead to jaw disorders, headaches, earaches, damaged teeth, chronic facial pains, and other problems. Therapy such as muscle relaxers and botox are currently used as remedies for bruxism. Alleged dental solutions include mouth guards and splints which appear to be designed to prevent damage to the teeth or decrease muscle activity. For example, U.S. Pat. No. 7,004,172 to Zacco shows a device which seeks to separate a user's mandibular and maxillary teeth by creating a space in the posterior portion of said mandibular and maxillary teeth. U.S. Pat. No. 6,886,566 to Eubank shows a device having a multiplicity of arches which act to maintain the tempromandibular joint in the proper position in an attempt to prevent bruxing. U.S. Pat. No. 6,675,804 to Pivovarov shows a device which maintains the tongue and mandibular and maxillary teeth in a position which seeks to eliminate the potential for bruxing. However, the device in Pivovarov encompasses both the mandibular and maxillary teeth, and is bulky and uncomfortable. U.S. Pat. No. 6,604,528 to Duncan shows a device that contains guide elements to position the device relative to the mouth and teeth and at the same time appears to prevent mating of the teeth when the mouth is closed and therefore gnashing or grinding of teeth during sleep. Yet, such devices heretofore shown in the art that are aimed to prevent bruxism or damage caused by bruxing fail to address or effectively aid in the treatment of snoring, OSA and GERD. An object and feature of the instant invention is the separation of the posterior teeth thereby eliminating the possibility of clenching which is a prerequisite for bruxing, while nonetheless permitting nocturnal jaw movements.
Hence, an object of the instant invention is the presentation of an effective intraoral appliance for treatment of sleep disorders including snoring, OSA, GERD or bruxing by moving the user's mandible forward with respect to the user's maxilla in order to open the airway in a manner which is comfortable, easily placeable, and without adverse effects. As shown above, prior devices have struggled to optimize the size and design parameters to facilitate the dual goals of comfort and effectiveness, but have woefully failed to achieve this goal. Thus, compliance is a predominant issue.

Intraoral mandibular advancement device for treatment of sleep disorders


A mode of a rectifier may be changed between at least fully passive and fully synchronous based upon direct current (DC) output by the rectifier and/or direct current voltage output by the rectifier. This extends the range of direct current output by the rectifier for a given range of DC voltage output by the rectifier.

A generator on aircraft is used to convert mechanical energy from an engine or a ram air turbine into alternating current (AC) electrical power, or to convert received AC electrical power into mechanical energy used to start the engine or the ram air turbine. Typically, a wound field generator or a brush generator is used. However, wound field generators typically are larger and heavier than other types of generators, and brush generators undesirably must periodically have their brushes replaced.

Apparatuses and methods for an alternating current to direct current converter


A feed pump designed as side-channel pump has a shaft for a rotationally fixed connection to an impeller. Two flattenings are arranged on the shaft so that they are nonparallel to one another. The impeller is thereby mountable on the shaft only in an intended position so that the impeller is rotated in an intended direction of rotation in a casing. The feed pump may therefore be assembled in a particularly simple way.

1. Field of the Invention
The invention relates to a feed pump for feeding fuel out of a fuel tank of a motor vehicle or for feeding washing fluid of a windshield washing system, the feed pump including a casing, an impeller arranged in the casing and connected on a driven shaft such that the impeller is fixed with respect to rotation relative to the driven shaft and such that a portion of the impeller is arranged with a slight clearance relative to the casing.
2. Description of the Related Art
Feed pumps for feeding fuel out of a fuel tank or for feeding washing fluid for a windshield washing system are typically designed as peripheral pumps or side-channel pumps and are known from practice. Each of these known pumps includes an impeller with guide blades for accelerating a medium to be fed and feeding the medium from an inlet channel to an outlet channel. The guide blades are shaped appropriately for the maximum possible efficiency. Accordingly, it is essential that the impeller be mounted in the intended direction of rotation during assembly in a pump casing. A shaft of the electric motor which drives the impeller usually has a lateral flattening at its free end and the impeller has a recess configured in conformity to the free end of the shaft for receiving the free end of the shaft. However, the dimensions of the guide blades for feeding fuel or washing fluid in a motor vehicle are usually very small and can therefore be ascertained only with great difficulty. As a consequence, there is no guarantee of a faultfree mounting of the impeller.
The object of the present invention is to design a feed pump such that the feed pump can be assembled in a particular simple and faultfree manner.
The object is met according to the present invention by a feed pump having an impeller connected to a shaft driven by an electric motor and at least one of the shaft and the impeller has means for mounting the impeller and shaft in the correct relative position.
This configuration prevents mounting of the feed pump when the impeller is not arranged in its intended position thereby ensuring that the impeller is arranged in its intended position on the shaft when the feed pump is mounted. This configuration prevents the impeller from being arranged out of place on the shaft, so that its direction of rotation in which the feed pump has high efficiency is fixed reliably. As a consequence, the impeller may be mounted in a very simple and faultfree way even when the guide blades have very small dimensions.
According to an embodiment of the invention, the means for mounting the impeller in the correct position are configured particularly simply in terms of design when the means for mounting the impeller in the correct position include a projection arranged near one of the end faces of the impeller arranged for engaging into a step-like recess of the shaft. The recess is configured in conformity to the projection. The shaft is held axially nondisplaceably with respect to the casing. Accordingly, the casing may be mounted only when the impeller is fastened in the correct position on the shaft.
According to another embodiment of the invention, the means for mounting the impeller in the correct position require a particularly low outlay in terms of construction when the means for mounting the impeller in the correct position include two flattenings on the outer surface of shaft which are nonparallel and/or have different dimensions and are arranged for connection to a correspondingly configured recess of the impeller. The connection is positive in the direction of rotation. This configuration allows the correct mounted position of the impeller on the shaft to be ascertained before the casing is mounted.
The feed pump according to the present invention has particularly high efficiency when the impeller includes means for the moveability of an outer edge of the impeller in a pivoting direction relative to the shaft of the electric motor about an axis arranged transversely to the shaft and/or in an axial direction relative to a radially inner region of the impeller. This configuration allows the radially outer region of the impeller to be tilted or slightly displaced by an intended amount in the casing. The position of the impeller in the casing may thereby be adapted in response to forces of an axial bearing acting between the impeller and the casing. The means for movability of the outer edge of the impeller leads to a simple assembly of the feed pump because the invention obviates the need for a particularly accurate mounting of the impeller. Rubbing of the impeller on the casing is reliably avoided as a result. Furthermore, the formation of noise is kept particularly low due to the present invention.
To generate the pivotability of the impeller with respect to the shaft, a particularly large play may be arranged between the impeller and the shaft. However, the large play produces rattling noises when the shaft is driven and in the case of fluctuations in flow in the feed pump. According to an embodiment of the present invention, rattling noises may be kept particularly low when the impeller has, in its region adjacent to the shaft, a depression which surrounds the shaft. This configuration allows the connection of the impeller to the shaft to be restricted to intended dimensions for an intended height of the impeller. In the case of the very small play of the impeller with respect to the shaft, these dimensions are critical for the intended pivotability of the impeller. Another advantage of this configuration is that the impeller does not rub on the casing in the region of the depression.
The depression may be arranged on one end face of the impeller. However, the generation of noise in the feed pump according to the present invention is further reduced when a depression is arranged in each of the two end faces of the impeller.
According to another embodiment of the invention, play between the shaft and the impeller is kept particularly low, along with an intended pivotability of the impeller, when the impeller is designed to be elastic at least in its radially inner region. In the most favorable case, the impeller may be pressed on the shaft. The elastic design of the radially inner region allows simple pivotability and axial movability of the radially outer edge of the impeller.
The elastic region of the impeller could be generated, for example, by the impeller having in this region an insert consisting of an elastic material. However, according to another advantageous development of the invention, the elastic region of the impeller is particularly cost-effective when the impeller has a groove arranged concentrically to the shaft.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of the disclosure. For a better understanding of the invention, its operating advantages, and specific objects attained by its use, reference should be had to the drawing and descriptive matter in which there are illustrated and described preferred embodiments of the invention.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.


Methods and systems are provided for creating an adaptive thesaurus. A term pair including an index term and an expansion term is received. A recall gain, an expansion independence, and a semantic similarity of the term pair are calculated using a processor. Whether to store the term pair is determined based on the recall gain, the expansion independence, and the semantic similarity. The term pair is stored based on the determination. Methods and systems are provided for searching using an adaptive thesaurus. A search query including a query term is received. An expansion term stored in association with an index term matching the query term in the adaptive thesaurus is retrieved. Using a processor, the search query is expanded using the expansion term based on a recall gain, an expansion independence, and a semantic similarity.

1. Technical Field
The present disclosure generally relates to searching information. More particularly, and without limitation, the present disclosure relates to methods and systems for creating an adaptive thesaurus and for enhancing a search using an adaptive thesaurus.
2. Background Information
With vast amounts of information being stored in electronic form, search tools help users find specific information they are looking for. For example, Internet search engines enable users to search for specific information on the Internet, and database search tools enable users to search for specific information stored in large databases. However, conventional search techniques have several problems, discussed below.
In the search field, the term "recall" refers to the proportion of all relevant documents in a corpus of documents that is retrieved by a search. In a Boolean full-text search engine, a query for "automobile" will fail to retrieve or "recall" any text that refers to the concept of automobiles using the term "car." Therefore, a user who searches for "automobile" may fail to find important and desired documents containing text that instead discuss automobiles using the term "car." Expanding the search query to "automobile OR car" will retrieve or "recall" the text missed by the "automobile" query. Accordingly, one strategy for improving recall is to enhance a query by expanding the original terms of the query with synonyms obtained from a thesaurus.
However, in general, no two terms are perfectly synonymous, and thus expansion of one term with a second term will typically result in a loss of precision. That is, searching for "automobile OR car" rather than just "automobile" will likely return texts with references to railroad car, which is not encompassed in the automobile concept being searched by the user. The inclusion of such texts that are irrelevant to automobiles would therefore diminish the "precision" of the search result, which refers to the proportion of all retrieved documents that are relevant to a given concept. If precision falls too low, a simple query expansion may fail to effectively enhance the search.
A second method of expanding a query to enhance the recall of texts pertaining to a concept is known as "stemming." For example, the concept of "to consider" can be referenced in a text by any of the following morphological variants of "to consider," i.e., consider, considers, considered, considering, and consideration. These variants can each be used to expand the other. However, as with the example of the railroad car, expanding "consider" with a non-synonymous morphological variant (e.g., considerate) will undesirably diminish precision, again failing to enhance the search.
Thus, there are several potential problems associated with query expansion. As the preceding examples illustrate, although query expansion increases recall by increasing the number of documents retrieved, it also normally reduces precision. This follows mathematically from the fact that the number of retrieved documents appears in the denominator of the formula for calculating precision. Queries must therefore be expanded to increase recall without significantly decreasing precision.
Another problem with query expansion is data glut. A data glut occurs when a search returns more texts than can be analyzed by the user. Since query expansion normally results in the recall of more texts, query expansion often entails a risk of creating a data glut. To mitigate this problem, query expansion may be accompanied by a relevance ranking system. A popular ranking algorithm called "term frequency-inverse document frequency" (TF-IDF) can rank texts returned by a search by "relevance" and order the most relevant retrieved texts at the top of a result set, thereby mitigating the data glut problem. Even still, expansion of a query with terms that occur too frequently or that are insufficiently synonymous can still create a data glut that the ranking algorithms cannot sufficiently mitigate.
Furthermore, words of natural languages may be polysemous (have multiple meanings). For example, in the English language, the word "bow" may be a gesture, a weapon, the front of a ship, or a decoration. Thus, using a conventional thesaurus to expand a search query for "prow" with "bow" will retrieve many texts unrelated to prow and thereby appreciably diminish precision. Conventional, general-purpose thesauri are therefore unsuited to specific domains of knowledge, because they contain weak or false synonyms that unacceptably diminish precision. Conversely, special-purpose thesauri are unsuited to general domains, because they may not contain commonly-accepted synonyms, and may fail to adequately expand queries to enhance recall.
In addition, conventional statistical thesauri (also known as association thesauri) use co-occurrence matrices, wherein terms that co-occur in a text are deemed synonyms. However, such synonyms do not comport with the usual linguistic definition of synonyms as terms that individually refer to a single concept. For example, the terms gun and bullet often co-occur in the same document. Consequently, conventional statistical methods of thesaurus construction will find the terms gun and bullet in frequent co-occurrence and will consider these two terms synonyms. Therefore, context-free expansion of a term with such false synonyms can lead to a considerable loss of precision.
In view of the foregoing, there is a need for improved methods and systems that provide accurate search results.

This patent is subject to a terminal disclaimer.

Methods and systems for creating and using an adaptive thesaurus

LexisNexis, a division of Reed Elsevier Inc.


An image forming apparatus includes: an image data processing unit that extracts one image area for each page from bitmap images for a continuous even number of pages of an identical sheet size and creates a combined image obtained by combining these image areas; and a print processing unit that prints the combined image on one print sheet or a size same as the sheet size.

1. Field of the Invention
The present invention relates to image forming apparatuses such as a digital copying machine and a printer and an image printing method of printing a bitmap image created by combining bitmap images for plural pages.
2. Description of the Related Art
As an image forming apparatus functioning as a digital copying machine and a printer, there is known an image forming apparatus having a function of printing a document with plural sheets on one print sheet (so-called N-in-1 printing function). For example, JP-A-2001-197286 discloses a method of forming a combined image of a document with sheets of different sizes or directions and printing the combined image on one print sheet.
In an N-in-1 printing method disclosed in JP-A-2001-197286, sizes of images actually drawn on sheets of the document, that is, image areas, are not taken into account. For example, in the case where a document comprised of A3 size sheets is subjected to N-in-1 print processing, it may be necessary to reduce A3 size to A4 size. In this case, even if a size of an image actually drawn on the sheet of A3 size is slightly larger than A4 size and other areas of the sheet are margins, A3 size including the image area and the margin area is reduced to A4 size. Therefore, an indistinct document including the small image area and the large margins is created.
When a user prints an image displayed on a display of a personal computer (PC), the user often performs print processing without knowing a size of the image or prints the image without checking a preview. In this case, although the user desires to print the image on one print sheet, the image may be divided according to a size of a sheet set in a printer and printed on plural sheets in a divided state. Even if the N-in-1 printing is performed, since gaps are formed among the divided images, it is impossible to obtain a print result desired by the user. When the print result desired by the user is not obtained in this way, sheets, toner, and the like are wasted. Further, since it is necessary to adjust the image size on software of the PC or a printer browser and repeat the printing, a work load imposed on the user increases.

Image forming apparatus and printing method for creating a combined image


An electron emitter assembly and a method for adjusting a size of electron beams are provided. The electron emitter assembly includes a laser configured to emit a first light beam. The electron emitter assembly further includes a lens assembly configured to receive the first light beam. The lens assembly is configured to adjust a size of the first light beam between a first predetermined size and a second predetermined size larger than the first predetermined size. The lens assembly emits the first light beam toward a photo-cathode. The photo-cathode is configured to emit a first electron beam having a third predetermined size when the first light beam having the first predetermined size contacts the photo-cathode. The photo-cathode is further configured to emit a second electron beam having a fourth predetermined size when the first light beam having the second predetermined size contacts the photo-cathode. The electron emitter assembly further includes an anode configured to receive the first and second electrons beams from the photo-cathode.

In computed tomography (CT) imaging systems, an x-ray source device and a detector array have been utilized to generate images of an object. The x-ray source device includes an electron emitter device that emits an electron beam that contacts a substrate that subsequently emits an x-ray beam in response to the electron beam.
A disadvantage of the CT imaging system is that the electron emitter device can only adjust a size of the electron beam by utilizing first and second heating coils in the electron emitter device which can only adjust the beam size over a relatively large amount of time.
Accordingly, there is a need for an improved electron emitter device that can adjust the size of an electron beam during relatively small amounts of time without utilizing heating coils.

Electron emitter assembly and method for adjusting a size of electron beams


The present disclosure describes a method utilizing an ion beam etch process, instead of a RIE etch process, to form magnetic tunnel junction (MTJ) structures. For example, the method includes forming MTJ structure layers on an interconnect layer, where the interconnect layer includes a first area and a second area. The method further includes depositing a mask layer over the MTJ structure layers in the first area and forming masking structures over the MTJ structure layers in the second area. The method also includes etching with an ion beam etch process, the MTJ structure layers between the masking structures to form MTJ structures over vias in the second area of the interconnect layer; and removing, with the ion beam etch process, the mask layer, the top electrode, the MTJ stack, and a portion of the bottom electrode in the first area of the interconnect layer.

Magnetic tunneling junctions (MTJs) are an integral part of magnetic random access memories (MRAMs). A fabrication process of an MTJ structure may involve a variety of operations, such as metal and dielectric depositions, photolithography and etch processes, etc. Some of these fabrication processes may damage the MTJ layers and compromise electrical properties of the resulting MTJ structures.

Taiwan Semiconductor Manufacturing Co., Ltd.


A system for acquiring environmental information measurements. The 5 system (100) utilize a sensor, (205) a front-end circuit, (310) a loop filter (315), a switch controller (206), and a reduced-order loop control circuit to provide reliable data measurements while providing robust system behavior. The system further includes a sensor simulator (330) for simulating the operation of the sensor (205) and testing the operation of the front-end circuit (310) and the loop filter (315).

This invention relates generally to data measurement and, more specifically, to a control system for data measurement.
Sensor equipment is used in a variety of applications to acquire environmental data measurements. The existing technology for acquiring data measurements suffers from a number of limitations. For example, the existing technology may suffer from a degradation of system performance as a result of system startup, system overloading, or stray capacitance within the system. Furthermore, testing the output of a sensor controller in the existing technology is time-consuming and expensive.
The present invention is directed to overcoming one or more of the limitations of the existing technology for acquiring environmental data measurements.


A query facility for database queries saves and re-uses query execution strategies, and automatically detects that a strategy should be re-optimized as a result of changes to an indexed variable value. Preferably, the number of records evaluated and selected by the index value condition is dynamically monitored during execution, and an alternative query strategy is initiated when this number appears to be out of proportion to expectations. In an exemplary embodiment, an indexed search strategy is changed to a table scan strategy (or vice versa) as a result of a change to the number of records eliminated by the indexed value, although other examples are possible. Preferably, the query engine initiates an alternative search strategy and concurrently continues to execute the original search strategy as separate threads. Search results are obtained from whichever thread completes first.

In the latter half of the twentieth century, there began a phenomenon known as the information revolution. While the information revolution is a historical development broader in scope than any one event or machine, no single device has come to represent the information revolution more than the digital electronic computer. The development of computer systems has surely been a revolution. Each year, computer systems grow faster, store more data, and provide more applications to their users.
A modern computer system typically comprises hardware in the form of one or more central processing units (CPU) for processing instructions, memory for storing instructions and other data, and other supporting hardware necessary to transfer information, communicate with the external world, and so forth. From the standpoint of the computer's hardware, most systems operate in fundamentally the same manner. Processors are capable of performing a limited set of very simple operations, such as arithmetic, logical comparisons, and movement of data from one location to another. But each operation is performed very quickly. Programs which direct a computer to perform massive numbers of these simple operations give the illusion that the computer is doing something sophisticated. What is perceived by the user as a new or improved capability of a computer system is made possible by performing essentially the same set of very simple operations, but doing it much faster. Therefore continuing improvements to computer systems require that these systems be made ever faster.
The overall speed at which a computer system performs day-to-day tasks (also called "throughput") can be increased by making various improvements to the computer's hardware design, which in one way or another increase the average number of simple operations performed per unit of time. The overall speed of the system can also be increased by making algorithmic improvements to the system design, and particularly, to the design of software executing on the system. Unlike most hardware improvements, many algorithmic improvements to software increase the throughput not by increasing the average number of operations executed per unit time, but by reducing the total number of operations which must be executed to perform a given task.
Complex systems may be used to support a variety of applications, but one common use is the maintenance of large databases, from which information may be obtained. Large databases usually support some form of database query for obtaining information which is extracted from selected database fields and records. Such queries can consume significant system resources, particularly processor resources, and the speed at which queries are performed can have a substantial influence on the overall system throughput.
Conceptually, a database may be viewed as one or more tables of information, each table having a large number of entries (analogous to row of a table), each entry having multiple respective data fields (analogous to columns of the table). The function of a database query is to find all rows, for which the data in the columns of the row matches some set of parameters defined by the query. A query may be as simple as matching a single column field to a specified value, but is often far more complex, involving multiple field values and logical conditions.
To support queries, a database typically includes one or more indexes for some of the database fields. An index is a sorting of the records in one of the database tables according to the value of a corresponding field. For example, if the database table contains records about people, one of the fields may contain a birthdate, and a corresponding index contains a sorting of the records by birthdate. If a query requests the records of all persons born before a particular date, the sorted index is used to find the responsive records, without the need to examine each and every record to determine whether there is a match. A well-designed database typically contains a respective index for each field having an ordered value which is likely to be used in queries.
Execution of a query involves retrieving and examining records in the database according to some search strategy. For any given logical query, not all search strategies are equal. Various factors may affect the choice of optimum search strategy. In particular, where a logical AND (or logical OR) of multiple conditions is specified, the sequential order in which the conditions are evaluated and the use of indexes can make a significant difference in the time required to execute the query.
If one of the conditions in a query having multiple conditions involves an indexed value, it is often, although not necessarily always, advantageous to use the index to identify a subset of records to be examined, and to examine only those records. As a simple example, suppose a query contains two conditions, A and B, conjoined by a logical AND, in which condition A involves comparing an indexed value to a constant. By accessing the index, it is possible to determine a subset of records which satisfy condition A, without the need to retrieve and examine all the records. This subset is typically obtained from a portion of the index as a form of sorted list. It is then possible to retrieve and examine each record on the sorted list to determine whether the record satisfies condition B. This type of execution strategy is referred to herein as an "index search".
In the above example, it would alternatively be possible to retrieve each and every record in the database table, to determine whether it satisfies one of the conditions (e.g., condition A), and if so, to determine whether it also satisfies the other condition. This type of execution strategy is referred to herein as a "table scan".
In general, the total number of records retrieved and examined will be fewer in the case of an index search, so it may appear that such a search would always be faster, or at least as fast. However, this is not always the case. When performing an index search, records are accessed in the indexed order, which is unrelated to the way in which the records are stored on a storage device, such as a rotating magnetic disk drive. Thus, from the standpoint of storage location, the order of record access is more or less random. On the other hand, when performing a table scan, records are retrieved in an order related to the way in which they are stored, to optimize storage accesses. E.g., records will typically be retrieved in sequentially addressed blocks of storage. If a single block (the smallest unit of I/O) contains multiple records, all records are retrieved at the same time and examined sequentially. Sequential blocks of storage are quickly accessed from a conventional disk drive data storage device, because there is generally little or no latency and seek time. Moreover, because sequential access is predictable, it is possible to access blocks from storage in advance of CPU need. As a result of these factors, the average amount of system resource required to retrieve and examine each record is significantly less in the case of a table scan than it is in the case of an index search.
In many cases, such as that of the simple example above, whether an index search is more efficient than a table scan will depend on the number of records eliminated from consideration by the index. In the simplified example above, if condition A is false for 99% of the records, then an index search will require that only 1% of the records be retrieved and examined for satisfaction of condition B. In this case, the index search is probably faster, notwithstanding the fact that the random nature of the access requires more resource per record examined. But if condition A is false for only 10% of the records, then a table search is probably faster, because the efficiencies of sequential access will outweigh the fact that slightly more records have to be examined.
To support database queries, large databases typically include a query engine which executes the queries according to some automatically selected search strategy, using the known characteristics of the database and other factors. Some large database applications further have query optimizers which construct search strategies, and save the query and its corresponding search strategy for reuse. These strategies include, among other things, whether an index search or a table scan will be conducted.
A re-usable query may include one or more imported variable values in its logical conditions. I.e., where the query compares a field of each database record to some value, the query may be written so that the compared-to value is a variable, to be provided ("imported") when the query is invoked for execution. In this manner, the same query can be re-used for multiple possible compared-to values, without the necessity of writing and maintaining separate queries for all possible compared-to values.
As explained above, whether an index search or a table scan is optimum for a given query depends largely on the relative number of records examined. A query optimizer or similar function may generate and save a search strategy for a query based on certain assumptions about the number of records eliminated from consideration by the indexed value. Since the number of records eliminated by the indexed value will depend on the value of the variable to which it is compared, this number could vary considerably for different executions of the same query if the query contains imported variables. A query strategy which is optimized using one variable value will not necessarily be optimal using a different query strategy. This problem can be particularly acute if a search strategy optimized for a particular variable value uses an index search, and, as a result of a change in the variable value, relatively few records are eliminated from consideration, resulting in an index search which evaluates almost the entire database table.
It would be possible to simply re-optimize a query every time it is executed, but this involves considerable overhead. If intelligent determinations could be made to automatically re-evaluate the execution strategies of queries under certain conditions, particularly where the relative number of records eliminated by an indexed value changes, the execution performance of such queries could be improved. A need therefore exists, not necessarily recognized, for an improved database query engine or optimizer which can automatically make intelligent choices in determining when to re-evaluate the execution strategies of certain queries.

Method and apparatus for re-evaluating execution strategy for a database query

International Business Machines Corporation


A disposable for use in blood treatment including a blood treatment unit and two membrane pumps connected in parallel on one side of the blood treatment unit. The disposable is operable in a single-needle mode, in which the pumps generate a pulsatile flow of blood through the blood treatment unit, and in a double-needle mode, in which the pumps generate an essentially continuous flow of blood through the blood treatment unit. The pumps connect to a supply of treatment fluid such that alternating flows of treatment fluid causes the pumps to generate the desired flows of blood in the single-needle and double-needle modes. The treatment fluid may be used as motive fluid for displacing the blood in the membrane pumps and/or as control fluid for controlling opening and/or closing of upstream and downstream commutation valves in the membrane pumps.

Today, various methods for hemodialysis are known, which include so-called double-needle or dual-needle (DN) dialysis and single-needle (SN) dialysis.
In DN dialysis, blood is withdrawn from a patient via one access device (e.g. a needle or catheter), and returned to the patient via another access device (e.g. a needle or catheter). A DN dialysis system is typically configured to generate a steady flow of blood from and to the patient, and to pump the blood continuously through the dialyzer.
In SN dialysis, one and the same access device (e.g. needle or catheter) is used for withdrawing and returning blood, which may be advantageous in a self-care setting since there is little risk of significant blood loss if the access device is accidentally dislodged from the patient. Also, when using SN dialysis, fewer needle punctures for accessing the patient's blood are required compared to DN dialysis. However, since SN dialysis withdraws and returns blood cyclically via one and the same access device, more time may be required for completing a dialysis treatment in comparison with DN dialysis.
Accordingly, DN dialysis has both advantages and disadvantages in comparison with SN dialysis, and vice versa. For this reason, it is desirable to offer blood treatment devices and dialysis machines that allow both DN and SN operation.
For home dialysis, as well as for dialysis in a clinical setting, it may be desirable to provide part of the dialysis system as a disposable which is designed to be attached to a dialysis machine. For ease of use and patient safety, such a disposable may comprise the extracorporeal blood circuit, including blood lines, connectors for access device(s), a dialyzer and a blood pump. At the start of a treatment, in such a scenario, the disposable may be connected to a dialysis machine so as to receive appropriately conditioned dialysis fluid and to be controlled to circulate the dialysis fluid through the dialyzer. After completed treatment, the disposable may be disconnected from the dialysis machine and discarded.
U.S. Pat. No. 6,645,166 discloses a disposable kit that permits both SN and DN operation when connected to a dialysis machine. The disposable kit comprises a dialyzer with an inlet connected to a feed line and an outlet connected to a return line. The feed line comprises two parallel line branches, each having a membrane pump. Each membrane pump comprises a pressure chamber, which is controlled to expand or compress by being alternately filled and emptied of a gas or a liquid, and electromagnetically or pneumatically actuated control valves on both sides of the pressure chamber to control the direction of the blood flow generated by the pressure chamber. For DN operation, the feed and return lines are connected to different access devices, and for SN operation, the feed and return lines are connected to a common access device. A connection line is arranged to extend between the outlet of the dialyzer and one of the membrane pumps and is provided with a control valve which is controlled to open or close to ensure a continuous flow of blood through the dialyzer in both DN and SN operation. Such a disposable kit requires use of a special dialysis machine, which has a dedicated system for alternately filling and emptying the pressure chamber with gas/liquid. It also requires the dialysis machine to provide proper control signals for the control valves. Still further, the disposable defines relatively complicated blood flow paths, which may lead to in an elevated risk for clogging, blood leakage and/or hemolysis.
The prior art also comprises US2009/0137940, which discloses a double diaphragm pump for application as a single use disposable medical blood pump, e.g. in dialysis systems. The pump comprises two pump chambers connected in parallel, where each pump chamber contains a flexible chamber diaphragm for pumping blood. An inlet valve and an outlet valve, in the form of diaphragm valves, are arranged on either side of each pump chamber. The operation of the pump is controlled by selectively applying vacuum or pneumatic pressure to the chamber diaphragm and the diaphragm valves. The pump is suggested for use in a dual-needle hemodialysis system, e.g. to generate a substantially constant blood flow from the patient to the extracorporeal circuit and/or from extracorporeal circuit to the patient, or to provide a pulsatile blood flow to the dialyzer downstream of the pump in the extracorporeal circuit and essentially constant blood flow from the patient to the extracorporeal circuit.
A similar pump, denoted PULSAR™ Blood Movement System, is described in "Renal Solutions™—Blood Pump", located at http://www.t-med.co.uk/dialysis/renalsolutions-bloodpump.htm. This pump consists of two chambers with a flexible medial diaphragm in each chamber. The top and bottom of each chamber opens to bloodlines; the back is attached to a pneumatic system, which is used to move the diaphragm. During dialysis, clamps below the chambers open and a vacuum is used to draw the diaphragm to the side of each chamber, which pulls blood into the chambers. The lower clamps then close, the upper clamps (between pump and dialyzer inlet) open, and positive pressure applied to the diaphragm pushes the blood from the chamber and towards the dialyzer. The chambers fill and empty in unison for SN dialysis and alternate, one filling while the other empties, in DN operation. It is stated that the pump is part of the arterial bloodline and designed as a single-use disposable. Such a disposable may operate with simple blood flow paths, but needs a special dialysis machine containing a pneumatic system for generating alternating positive and negative pressures within the pump chambers. The dialysis machine must also be provided with adequately controlled clamps.
US2010/0241062 discloses a medical fluid pump system comprising reciprocating piston heads which are attached to a membrane that defines a pair of fluid pump chambers. Thereby, the pump system contains a pair of mechanically actuated membrane pumps. The movement of fluid into and out of the fluid pump chambers is controlled by selectively inflating and deflating inflatable members, which thereby are brought into and out of contact with depressible dome regions in flow channels extending to the fluid pump chambers.
The prior art also comprises WO2009/127627, which aims at eliminating the need for pressure sensors in the blood lines of the extracorporeal circuit in a dialysis system. This is achieved by arranging one or more membrane pumps as blood pumps in the extracorporeal circuit, and using the dialysis fluid as working medium of the membrane pump, whereby the pressure of the dialysis fluid may be monitored for measuring the pressure of the blood in the extracorporeal circuit.

Disposables for blood treatment, and methods of operating the same


The invention concerns new tumor necrosis factor receptor associated factors, designated TRAF. The new factors are capable of specific association with the intracellular domain of the type 2 TNF receptor (TNF-R2), and are involved in the mediation of TNF biological activities.

The present invention concerns novel polypeptide factors. More particularly, the invention concerns factors associated with the type 2 tumor necrosis factor receptor (TNF-R2).
Tumor necrosis factor (TNF, also referred to as TNF-xcex1) is a potent cytokine produced mainly by activated macrophages and a few other cell types. The large number of biological effects elicited by TNF include hemorrhagic necrosis of transplanted tumors, cytotoxicity, a role in endotoxin shock, inflammatory, immunoregulatory, proliferative, and antiviral responses [reviewed in Goeddel, D. V. et al., Cold Spring Harbor Symposia on Quantitative Biology 51, 597-609 (1986); Beutler, B. and Cerami, A., Ann. Rev. Biochem. 57, 505-518 (1988); Old, L. J., Sci. Am. 258(5), 59-75 (1988); Fiers, W. FEBS Lett. 285(2), 199-212 (1991)]. The literature has reported that TNF and other cytokines such as IL-1 may protect against the deleterious effects of ionizing radiation produced during the course of radiotherapy, such as denaturation of enzymes, lipid peroxidation, and DNA damage [(Neta et al., J. Immunol. 136(7): 2483, (1987); Neta et al., Fed. Proc. 46: 1200 (abstract), (1987); Urbaschek, Lymphhokine Res. 6:179 (1987); U.S. Pat. No. 4,861,587; Neta et al., J. Immunol. 140: 108 (1988)]. A related molecule, lymphotoxin (LT, also referred to as TNF-xcex2), that is produced by activated lymphocytes shows a similar but not identical spectrum of biological activities as TNF (see, e.g. Goeddel, D. V. et al., supra, and Fiers, W., supra). TNF was described by Pennica et al., Nature 312, 721 (1984); LT was described by Gray et al., Nature 312. 724 (1984).
The first step in the induction of the various cellular responses mediated by TNF or LT is their binding to specific cell surface receptors. Two distinct TNF receptors of approximately 55-kDa (TNF-R1) and 75-kDa (TNF-R2) have been identified [Hohmann, H. P. et al., J. Biol. Chem. 264, 14927-14934 (1989); Brockhaus, M. et al., Proc. Natl. Acad. Sci. USA 87, 3127-3131 (1990)], and human and mouse cDNAs corresponding to both receptor types have been isolated and characterized [Loetscher, H. et al., Cell 61, 351 (1990); Schall, T. J. et al., Cell 61, 361 (1990); Smith, C. A. et al., Science 248, 1019 (1990); Lewis, M. et al., Proc. Natl. Acad. Sci. USA 88, 2830-2834 (1991); Goodwin, R. G. et al., Mol. Cell. Biol. 11, 3020-3026 (1991)]. Both TNF-Rs share the typical structure of cell surface receptors including extracellular, transmembrane and intracellular regions. The extracellular portions of both receptors are found naturally also as soluble TNF-binding proteins [Nophar, Y. et al., EMBO J. 9, 3269 (1990); and Kohno, T. et al., Proc. Natl. Acad. Sci. U. S. A.,87 8331 (1990)]]. The amino acid sequence of human TNF-R1 and the underlying nucleotide sequence are disclosed in EP 417,563 (published Mar. 20, 1991), whereas EP 418,014 (published Mar. 20, 1991) discloses the amino acid and nucleotide sequences of human TNF-R2.
Although not yet systematically investigated, the majority of cell types and tissues appear to express both TNF receptors.
The individual roles of the two TNF receptors, and particularly those of TNF-R2, in cell signaling are far from entirely understood, although studies performed by poly- and monoclonal antibodies (mAbs) that are specific for either TNF-R1 or TNF-R2 have provided some very valuable insight into the functions and interactions of these receptors.
It has been observed that both polyclonal and monoclonal antibodies directed against TNF-R1 can act as specific agonists for this receptor and elicit several TNF activities such as cytotoxicity, fibroblast proliferation, resistance to chlamydiae, and synthesis of prostaglandin E2 [Engelmann, H. et al., J. Biol. Chem. 265. 14497-14504 (1990); Espevik, T. et al., J. Exp. Med. 171, 415-426 (1990); Shalaby, M. R. et al., J. Exp. Med. 172, 1517-1520 (1990)]. Agonist antibodies to TNF-R1 with antiviral activity are disclosed in copending application Ser. No. 07/856,989 filed Mar. 24, 1992.
In addition, polyclonal antibodies to both murine TNF-R1 and TNF-R2 have been developed, have been shown to behave as specific receptor agonists and induce a subset of murine TNF activities. While the murine TNF-R1 was shown to be responsible for signaling cytotoxicity and the induction of several genes, the murine TNF-R2 was shown to be capable of signaling proliferation of primary thymocytes and a cytotoxic T cell line, CT6 [Tartaglia, L. A. et al., Proc. Natl. Acad. Sci. USA 88, 9292-9296 (1991)]. The ability of TNF-R2 to stimulate human thymocyte proliferation has been demonstrated in experiments with monoclonal antibodies directed against the human receptor.
Monoclonal antibodies against human TNF-R1 that block the binding of TNF to TNF-R1 and antagonize several of the TNF effects have also been described [Espevik, T. et al., Supra; Shalaby, M. R. et al., Supra; Naume, B. et al., J. Immunol. 146, 3035-3048 (1991)].
In addition, several reports described monoclonal antibodies directed against TNF-R2 that can partially antagonize the same TNF responses (such as cytotoxicity and activation of NF-xcexaB) that are induced by TNF-R1 agonists [Shalaby, M. R. et al., Supra; Naume, B. et al., Supra; and Hohmann, H. P. et al., J. Biol. Chem. 265, 22409-22417 (1990)].
It is now well established that although the two human TNF receptors are both active in signal transduction, they are able to mediate distinct cellular responses. While TNF-R1 appears to be responsible for signaling most TNF responses, the thymocyte proliferation stimulating activity of TNF is specifically mediated by TNF-R2. In addition, TNF-R2 activates the transcription factor NF-xcexaB (Lenardo and Baltimore, Cell 58: 227-229 [1989]) and mediates the transcriptional induction of the granulocyte-macrophage colony stimulating factor (GM-CSF) gene (Miyatake et al., EMBO J. 4: 2561-2568 [1985]; Stanley et al., EMBO J. 4: 2569-2573 [1985]) and the A20 zinc finger protein gene (Opipari et al., J. Biol. Chem. 265: 14705-14708 [1990]) in CT6 cells. TNF-R2 also participates as an accessory component to TNF-R1 in the signaling of responses primarily mediated by TNF-R1, like cytotoxicity ( [Tartaglia, L. A. and Goeddel, D. V., Immunol. Today 151-153 [1992]).
Although TNF itself, the TNF receptors and TNF activities mediated by the two receptors have been studied extensively, the post-receptor signal transduction mechanisms are unknown (see the review article by Beyaert, R. and Fiers, W., xe2x80x9cMolecular mechanisms of tumor necrosis factor-induced cytotoxicity: what we do understand and what we do notxe2x80x9d, FEBS Letters 340, 9-16 (1994)). This is especially true for the very first step in the TNF receptor signal transduction cascade, i.e. for the question of how the membrane-bound receptor sends a signal into the cell after activation by the ligand, TNF.
The present invention is based on the hypothesis that polypeptide factors associated with the intracellular domain of TNF-R2 exist and participate in the TNF-R2 signal transduction cascade. More specifically, this invention is based on research directed to the identification and isolation of native polypeptide factors that are capable of association with the intracellular domain of TNF-R2 and participate in the intracellular post-receptor signaling of TNF biological activities.
It is known that the TNF induced proliferation of murine CT6 cells is mediated by TNF-R2 (Tartaglia et al., [1991], supra). To identify factors that are associated with the intracellular domain of hTNF-R2, the receptor was immunoprecipitated from lysates of [35S]-labeled transfected CT6 cells and from unlabeled transfected human embryonic kidney 293 cells, which were then incubated with labeled lysate from untransfected CT6 cells. Several polypeptides with apparent molecular weights of 45-50 kD and one with an approximate molecular weight of 68 kD were specifically coprecipitated with the immunoprecipitated hTNF-R2. These are hereinafter collectively referred to as tumor necrosis factor receptor associated polypeptides, or TRAFs. Of the factors identified two have so far been purified and cloned. These two factors are designated as tumor necrosis factor receptor associated factors 1 and 2 (TRAF1 and TRAF2; SEQ. ID. NOs: 2 and 4). A comparison of the amino acid sequences of TRAF1 and TRAF2 revealed that they share a high degree of amino acid identity in their C-terminal domains (53% identity over 230 amino acids), while their N-terminal domains are unrelated. These new factors are believed to play a key role in the post-receptor signaling of TNF. Since the intracellular domain of TNF-R2 does not display any sequence homology to any other known receptor or protein, these signaling molecules might represent a novel signal transduction mechanism, the understanding of which can greatly contribute to the development of new strategies to improve the therapeutic value of TNF.
In one aspect, the present invention concerns a family of novel factors (TRAFs) capable of specific association with the intracellular domain of a native TNF-R2. The invention specifically concerns tumor necrosis factor receptor associated factors 1 and 2 (TRAF1 and TRAF2, SEQ. ID. NOs. 2 and 4), including the native factors from any human or non-human animal species and their functional derivatives.
In another aspect, the invention concerns an isolated nucleic acid molecule comprising a nucleotide sequence encoding a TRAF polypeptide.
In yet another aspect, the invention concerns an expression vector comprising the foregoing nucleic acid molecule operably linked to control sequences recognized by a host cell transformed with the vector.
In a further aspect, the invention concerns a host cell transformed with the foregoing expression vector.
In a still further aspect, the invention concerns molecules (including polypeptides, e.g. antibodies and TRAF analogs and fragments, peptides and small organic molecules) which disrupt the interaction of a TNF-R2 receptor associated factor and TNF-R2.
The invention specifically concerns antibodies, capable of specific binding to a native TRAF polypeptide, and hybridoma cell lines producing such antibodies.
In a different aspect, the invention concerns a method of using a nucleic acid molecule encoding a TRAF polypeptide as hereinabove defined, comprising expressing such nucleic acid molecule in a cultured host cell transformed with a vector comprising said nucleic acid molecule operably linked to control sequences recognized by the host cell transformed with the vector, and recovering the encoded polypeptide from the host cell.
The invention further concerns a method for producing a TRAF polypeptide as hereinabove defined, comprising inserting into the DNA of a cell containing nucleic acid encoding said polypeptide a transcription modulatory element in sufficient proximity and orientation to the nucleic acid molecule to influence the transcription thereof.
The invention also provides a method of determining the presence of a TRAF polypeptide, comprising hybridizing DNA encoding such polypeptide to a test sample nucleic acid and determining the presence of TRAF polypeptide DNA.
In a further aspect, the invention concerns an isolated nucleic acid molecule encoding a fusion of an intracellular domain sequence of a native TNF-R2 and the DNA-binding domain of a transcriptional activator.
In a still further aspect, the invention concerns an isolated nucleic acid molecule encoding a fusion of a TRAF to the activation domain of a transcriptional activator.
The invention further concerns hybrid (fusion) polypeptides encoded by the foregoing nucleic acids.
The invention also covers vectors comprising one or both of the nucleic acid molecules encoding the foregoing fusion proteins.
In a different aspect, the invention concerns an assay for identifying a factor capable of specific binding to the intracellular domain of a native TNF-R2, comprising
(a) expressing, in a single host cell carrying a reporter gene, nucleic acid molecules encoding a polypeptide comprising a fusion of an intracellular domain sequence of a native TNF-R2 to the DNA-binding domain of a transcriptional activator, and a fusion of a candidate factor to the activation domain of a transcriptional activator; and
(b) monitoring the binding of the candidate factor to the TNF-R2 intracellular domain sequence by detecting the molecule encoded by the reporter gene.
The invention further relates to an assay for identifying a factor capable of specific association with the intracellular domain of a native TNF-R2, comprising
(a) expressing nucleic acid molecules encoding a polypeptide comprising a fusion of an intracellular domain sequence of a native TNF-R2 to the DNA-binding domain of a transcriptional activator, and a second polypeptide comprising a fusion of a candidate polypeptide factor to the activation domain of a transcriptional activator, in a single host cell transfected with nucleic acid encoding a polypeptide factor capable of specific binding to said TNF-R2, and with nucleic acid encoding a reporter gene; and
(b) monitoring the association of said candidate factor with said TNF-R2 or with said polypeptide factor capable of specific binding to said TNF-R2 by detecting the polypeptide encoded by said reporter gene.
In a further aspect, the invention concerns an assay for identifying a molecule capable of disrupting the association of a TRAF with the intracellular domain of a native TNF-R2, comprising contacting a cell expressing 1. a fusion of an intracellular domain sequence of a native TNF-R2 to the DNA-binding domain of a transcriptional activator, 2. a fusion of a native TRAF polypeptide to the activation domain of said transcriptional activator, and 3. a reporter gene, with a candidate molecule, and monitoring the ability of said candidate molecule to disrupt the association of said TRAF and TNF-R2 intracellular domain sequence by detecting the molecule encoded by the reporter gene. The cell, just in the previous assays is preferably a yeast cell.
In addition to the xe2x80x9ctwo-hybridxe2x80x9d format described above, the assay my be performed in any conventional binding/inhibitor assay format. For example, one binding partner (TNF-R2 or TRAF) may be immobilized, and contacted with the other binding partner equipped with a detectable label, such as a radioactive label, e.g. 32P and the binding (association) of the two partners is detected in the presence of a candidate inhibitor. The design of a specific binding assay is well within the skill of a person skilled in the art.
In a different aspect, the invention concerns a method of amplifying a nucleic acid test sample comprising priming a nucleic acid polymerase reaction with nucleic acid encoding a TRAF polypeptide, as defined above.
In another aspect, the invention concerns a method for detecting a nucleic acid sequence coding for a polypeptide molecule which comprises all or part of a TRAF polypeptide or a related nucleic acid sequence, comprising contacting the nucleic acid sequence with a detectable marker which binds specifically to at least part of the nucleic acid sequence, and detecting the marker so bound.
In yet another aspect, the invention concerns a method for treating a pathological condition associated with a TNF biological activity mediated, fully or partially, by TNF-R2, comprising administering to a patient in need a therapeutically effective amount of a TRAF or a molecule capable of disrupting the interaction of a TRAF and TNF-R2.

Tumor necrosis factor receptor-associated factors


A method for tuning a vibratory device including a cantilevered resonator comprising the steps of increasing a voltage V0 supplied to the vibratory device to thereby increase the bandwidth of the vibratory device; and keeping the resonant frequency of the vibratory device at substantially that natural frequency of the cantilevered resonator, wherein the vibratory device comprises: a capacitor including a movable plate and a fixed plate spaced from each other, the movable plate being part of the cantilevered resonator; a voltage source connected to the capacitor for providing voltage V0 across the capacitor to produce an attractive force between movable plate and fixed plate; a circuit connecting the voltage source to the capacitor; and a load resistor in said circuit having a resistance RL satisfying the following equation:   μ  =                    ω        0                          c        0                          R        L                    (              1        -        λ            )      where: μ is at least 10; ω0 is the beam constant for the cantilevered resonator; c0 is the capacitance for the capacitor; and λ is the voltage dependent coupling parameter for voltage V0.

1. Field of the Invention
The present invention relates to a tunable MEMS resonator and a method for actively tuning a MEMS resonator.
2. Description of the Prior Art
Microelectromechnical systems (MEMS) are miniaturized devices that provide low power consumption, and high frequency and greater sensitivity. MEMS components may be etched from a single material, such as crystal silicon. Prior devices have incorporated the technology of MEMS to resonators.
However, prior MEMS resonators have several limitations. One limitation is that prior MEMS resonators may only have resonant frequency changed in one direction, i.e. an increase the resonant frequency, and do not have the capability to have resonant frequencies both increased and decreased from the natural resonant frequency. In addition, another limitation of prior MEMS resonators is that the bandwidth Q is inadvertently changed and reduced along with the change in resonant frequency. Prior MEMS resonators also have no capability to have the resonant frequency and bandwidth of the resonators independently tuned.
A characteristic problem of MEMS resonators is that resonant frequency and bandwidth, i.e. Q value, which are strongly set by the mechanical properties of the resonators require tuning in real environments. This problem limits the applicability of MEMS resonators.

Multi-tunable microelectromechanical system (MEMS) resonators


An image display controlling apparatus comprises a memory means for storing an attention area information and a date and time information for each image data of a plurality of images to be displayed on an image display means, an evaluation means for evaluating the attention area information based on a standard date and time information and the date and time information and producing a protection area information for a protection area set within the attention area, and an adjusting means for listing and displaying the plurality of the images with a superimposition controlled based on the protection area information, the plurality of the images are listed and displayed.

1. Field of the Invention
The present invention relates to an image display controlling apparatus, an image display controlling method and an image display controlling program, which can be employed particularly preferably in a technique for displaying a plurality of image data easily viewable by a viewer in an apparatus for displaying and observing digital image data.
2. Description of the Relates Art
With the start of the digital high vision broadcast and spread of television receivers compatible to the high vision, dynamic and high quality video images can be enjoyed compared with the conventional ones. In contrast, according to the spread of electronic still cameras, more and more users enjoy electronic still images and video images displayed not only on a personal computer but also on a television monitor screen.
Then, in the case the user view a still image or a video image on the television receiver, in general, the user selects the data to be reproduced by viewing a list of thumbnails displayed on the monitor screen and selecting the thumbnail.
In contrast, recently, a memory with the memory capacity dramatically increased can be utilized, and thereby the number of the images to be stored is increased dramatically. For example, digital photographs of more than 500 pieces can be stored in a memory card. Therefore, it is not easy for a user to find out a desired image datum out of the image data of the large amount.
As a technique for arranging the image data of a large amount efficiently on a screen for facilitating the selection by the user himself, for example, the techniques disclosed in the patent document 1 (Unexamined Patent Publication No. 2001-306375) and the patent document 2 (Unexamined Patent Publication No. Hei 09-259130) can be presented. Among them, the patent document 1 discloses a technique for easily finding out desired data by moving thumbnail images while superimposing and displaying the same. Moreover, the patent document 2 discloses a technique for finding out desired data by displaying the image data in a three dimensional space (3D space) and moving the virtual view point.
However, according to the above-mentioned conventional techniques, since the thumbnail images are displayed while being superimposed, and thus the important portions for judging the photographs can be hidden.
Specifically, as shown in FIG. 18, for example, in the case the photograph (a) and the photograph (b) are present as the thumbnail images, the image of the "running" children on the left side of the image is the important portion in the photograph (a), and on the other hand, the person on the right side of the image in the photograph (b) is the important portion.
However, in the case these photographs are displayed with the other photographs while being superimposed, as shown in FIG. 18, they may be displayed with the important portions hidden. Therefore, according to the inventions displayed in the above-mentioned patent documents 1 and 2, a method of judging the photographs for viewing the important portions of the photographs by the operation of scrolling the displayed images or moving the virtual view point positions by the user had to be adopted.

Image display controlling method, image display controlling apparatus and image display controlling program


A method for measuring a magnetic read width MRW of a magnetic read sensor directly from the derivative of a full track profile, with better accuracy and more advantages than the micro-track method was invented and also there is no need to use a separate wide write head. The magnetic write width MWW of the write head, without the influence of sensor side reading, can also be obtained by this method along with the MRW with no additional calculations.

A main component of a computer is an assembly that is referred to as a magnetic hard disk drive, HDD. The HDD includes rotating magnetic disks, write and read heads that are suspended by a suspension arm adjacent to the surfaces of the rotating magnetic disks and an actuator that swings the suspension arm to place the read and write heads over selected circular tracks on the rotating disks. The read and write heads are directly located on a slider that has an air bearing surface (ABS). The suspension arm biases the slider into contact with the surface of the disk when the disk is not rotating but, when the disk rotates, air is swirled by the rotating disk. When the slider rides on the air bearing, the write and read heads are employed for writing magnetic impressions to and reading magnetic impressions from the rotating disk. The read and write heads are connected to processing circuitry that operates according to a computer program to implement the writing and reading functions.
The write head includes a coil layer embedded in insulation layers (insulation stack), the insulation stack being sandwiched between first and second pole piece layers. A gap is formed between the first and second pole piece layers by a gap layer at the air bearing surface (ABS) of the write head and the pole piece layers are connected at the back gap. Current conducted to the coil layer induces a magnetic flux in the pole pieces which causes a magnetic field to fringe out at a write gap at the ABS for the purpose of writing the aforementioned magnetic impressions in tracks on the moving media, such as in circular tracks on the aforementioned rotating disk.
In recent read head designs a spin valve sensor, also referred to as a giant magnetoresistive (GMR) sensor, has been employed for sensing magnetic fields from the rotating magnetic disk. The sensor includes a nonmagnetic conductive layer, hereinafter referred to as a spacer layer, sandwiched between first and second ferromagnetic layers, hereinafter referred to as a pinned layer and a free layer. First and second leads are connected to the spin valve sensor for conducting a sense current. The magnetization of the pinned layer is pinned perpendicular to the air bearing surface (ABS) and the magnetic moment of the free layer is located parallel to the ABS, but free to rotate in response to external magnetic fields. The magnetization of the pinned layer is typically pinned by exchange coupling with an antiferromagnetic layer.
The thickness of the spacer layer is chosen to be less than the mean free path of conduction electrons through the sensor. With this arrangement, a portion of the conduction electrons is scattered by the interfaces of the spacer layer with each of the pinned and free layers. When the magnetizations of the pinned and free layers are parallel with respect to one another, scattering is minimal and when the magnetizations of the pinned and free layer are antiparallel, scattering is maximized. Changes in scattering alter the resistance of the spin valve sensor in proportion to cosθ, where θ is the angle between the magnetizations of the pinned and free layers. In the read mode the resistance of the spin valve sensor changes proportionally to the magnitudes of the magnetic fields from the rotating disk. When a sense current is conducted through the spin valve sensor, resistance changes cause potential changes that are detected and processed as playback signals.
A spin valve sensor is characterized by a magnetoresistive (MR) coefficient that is substantially higher than the MR coefficient of an anisotropic magnetoresistive (AMR) sensor. For this reason a spin valve sensor is sometimes referred to as a giant magnetoresistive (GMR) sensor. When a spin valve sensor employs a single pinned layer it is referred to as a simple spin valve. When a spin valve employs an antiparallel (AP) pinned layer it is referred to as an AP pinned spin valve. An AP spin valve includes first and second magnetic layers separated by a thin non-magnetic coupling layer such as Ru. The thickness of the spacer layer is chosen so as to antiparallel couple the magnetizations of the ferromagnetic layers of the pinned layer. A spin valve is also known as a top or bottom spin valve depending upon whether the pinning layer is at the top (formed after the free layer) or at the bottom (before the free layer).
A critical performance parameter for a read head or a write head is the magnetic track width that can be read or written by the head. A write head having the smallest possible magnetic write width (MWW) while having sufficient performance is of course desired. Similarly, magnetic read sensors are designed to have the smallest possible magnetic read width (MRW) while having sufficient signal amplitude to allow the largest possible density of data tracks to be recorded on a given magnetic disk.
Since the track width, (MRW, or MWW) is such a critical parameter, one can appreciate the importance of having an accurate means of measuring the MRW for a read sensor.
Magnetic read width, MRW, is defined as the half maximum width of reader response function in the cross track direction. The definition of reader response function should be:R(x)=Lim(micro-track width-0)Amplitude of output signal(x)/width of micro-track.Where x is the position of reader in the cross track direction and micro-track is a data track on the media with a width much narrower than MRW. Therefore, a current method, that has been used to measure a read head MRW and has currently been considered the best one, has required the creation of a micro track of data. A micro track is constructed by a multi-step process that involves first recording a magnetic track, also known as a full-track, and then erasing, or "shaving off" one or both sides of the data track, leaving just a very small portion of the track that is much narrower than the actual track width of the read head as well as the write head.
This micro-track is then read while moving the read sensor from side to side until the signal drops to ½ of that which it was at its peak value. The distance between those points is defined as the value of the MRW in this micro-track measurement.
The key to having accurate and reliable results using this method is to obtain a micro-track with fixed and narrow-enough track width. However, when track pitch becomes very narrow it is very difficult to obtain such a micro-track with strong enough signal relative to be background noise level and consistent micro-track width from run to run. This is exacerbated by several factors such as TMR (Track Misregistration), spindle runout, write width variation, etc, especially at high frequencies. There also remains a great deal of disagreement over what method should best be used to generate such a micro-track. For example, some researchers believe that the micro-track should be generated using a DC erase, while others prefer an AC erase. Whether the erasure should be made on one side or both sides of the full-track is still a controversial subject now.
Therefore, as track width becomes smaller, there is a strong felt need for a means for measuring the magnetic read width (MRW) of a read head directly from a full track profile, without the need for creating a micro-track. Such a means for measuring MRW would not only eliminate a lot of unnecessary confusion and arguments regarding how to generate a micro-track, but would also allow us to have much more accurate results for the measurement of very narrow track widths, such as those of current and future disk drive products. Such a means for measuring track width would also preferably be useful in a production disk drive, since the creation of a micro-track would not be necessary.

Full track profile derivative method for read and write width measurements of magnetic recording head

Hitachi Global Storage Technologies, Netherlands B.V.


A voice coil motor (VCM) includes a fixing portion, a moving portion, a magnet assembly, a coil, and an elastic sheet. The fixing portion includes an upper plate and a sidewall extending from edges of the upper plate. The moving portion is received in the fixing portion, and includes a top surface and an outer surface connected to the top surface. The moving portion defines a plurality of glue receiving recesses in the top surface and a plurality of second connecting portions each extending from a bottom surface of each glue receiving recess. The magnet assembly is fixed on the inner surface. The coil is circled around the outer surface of the moving portion, and is opposite to the magnet assembly. The elastic sheet is connected between the first connecting portions and the second connecting portions.

1. Technical Field
The present disclosure relates to voice coil motors (VCMs) and, particularly, to a VCM avoiding glue from overflowing and a lens module using the VCM.
2. Description of Related Art
VCMs are used in lens modules for image focusing. Each VCM generally includes a moving portion, a fixing portion, and an elastic sheet connected between the moving portion and the fixing portion. The elastic sheet is generally connected to the fixing portion using glue. An amount of the glue must be enough to avoid the elastic sheet from being separated from the fixing portion. However, if the glue overflows to a space between the fixing portion and the moving portion, the result will be that the moving portion will not able to move relative to the fixing portion.
Therefore, it is desirable to provide a VCM that can overcome the limitations described.