A method for permanently sealing an ultra-high vacuum within a glass enclosure. This is accomplished by first forming a hole, either in one of the flat plates that form the enclosure or in one of the standoffs that separate the plates, and then sealing a metal tube to the glass. In one embodiment, the metal tube is positioned so as to be partly inside the hole while in another a flange at the end of the tube is positioned to cover the hole. In both cases, a glass frit paste is then applied all around the glass metal interface. This is followed by heating so that the frit softens and becomes a glass-to-metal seal. Once the structure has cooled down the attached metal tube is used as a pumping port to evacuate it and, while still under vacuum, the metal tube is pinched off to form a permanent seal.

(1) Field of the Invention
The invention relates to the general field of vacuum enclosures, more particularly to flat panel displays and methods for sealing in the vacuum.
(2) Description of the Prior Art
A considerable body of art already exists with respect to ways to seal a permanent vacuum inside a glass or metal enclosure. Most widely used is the tipping off method wherein the glass enclosure includes a tube that is an integral part of it, being either cast or blown in place during manufacture. This tube is then used as a vacuum port through which the interior of the structure is evacuated. Once the requisite level of vacuum has been achieved, the tube is heated over a small annular area well removed from the main enclosure. This heat treatment serves to soften the glass which, under the influence of atmospheric pressure, then slowly collapses until the vacuum has been sealed in place. The heat is then immediately removed to prevent further collapse and any tubing that extends beyond the seal is removed.
There are several problems associated with the tipping off method outlined above. Even though a good vacuum may have been achieved just prior to tip-off, the softening of the glass results in considerable outgassing, just as evacuation ceases, so the final permanent vacuum inside the enclosure is only of the order of 10.sup.-4 torr. In order to achieve an acceptable level of vacuum it becomes necessary to make use of a gettering procedure. While usually effective, gettering adds significantly to the overall cost of manufacturing the product.
Another problem associated with tip-off is that the glass material used is fragile. Aside from being susceptible to mechanical breakage during its life, there is also the possibility that the tip-off tube may crack during sealing if the heat is not uniformly applied. Finally, heaters that generate temperatures around 1,000.degree. C. need to be provided for tip-off to work reliably in a production environment. Such heaters, temperature cycled many times a day, have a relatively short operating life, further adding to the manufacturing costs.
A different approach to the problem of sealing in a permanent vacuum is pinch-off. Here, the tube that is used for the vacuum port is made of metal. Once the requisite vacuum level has been achieved, the metal tube is pinched off using a suitable crimping tool. The latter is a pair of parallel jaws that press in on the tube from opposite sides. The metal is soft enough so that it deforms without cracking until the inner surfaces (of the tubing) that are being pushed together meet and then fuse as a cold weld. Provided the jaws remain parallel while the tube deforms and the inside surface of the tubing is free of grease, oxide, etc., the weld that is formed provides an effective vacuum tight seal. Any excess metal tubing is then removed.
The pinch-off method enjoys several advantages over tip-off. In particular, since no heating is involved there is no danger to the nearby glass enclosure that has been evacuated and, since outgassing is avoided, gettering is not usually needed, although it may still be used if an exceptionally high vacuum is to be maintained over a long period of time. The main problem with using pinch-off is how to achieve a reliable, low cost connection between the metal tubing that is to be pinched-off and the glass enclosure itself. In the current art, such glass to metal unions are formed by glass-to-metal seals or by housekeeper seals. These are limited to a small subset of both metal and glass types. In general, the metals are limited to OFHC copper, stainless steel 304, nickel, and gold, while the glass has been limited to Corning codes 7740 and 7052FN. A wider selection of glasses and metals has not been used because of thermal mismatch problems as well as cost.
A number of references relating to this problem can be found but none, as will be seen, anticipates the present invention. Akimoto et al. (U.S. Pat. No. 5,336,287 August 1994) describe a method for bonding metal to glass. A glass frit is used but the key feature of the invention is the inclusion of an aluminum borate whisker in the frit mix. The metal that is used is in the form of a stud that is to be bonded to the glass surface. The relative expansion coefficients of glass, metal, and frit are all carefully controlled.
Glass frit is also used by Tsukui et al. (U.S. Pat. No. 5,304,890 April 1994) to weld a reinforcing frame to a cathode ray tube while Schoene (U.S. Pat. No. 4,713,580 December 1987) teaches how a seal button may be used as part of assembling a metal vapor arc discharge lamp.

Seal for vacuum devices and methods for making same

Industrial Technology Research Institute


Disclosed is a universally-adaptable cell preconditioning and storage medium that can be used for the effective cryopreservation of cells at temperatures less than 4xc2x0 C. The aqueous medium contains adenosine, a calcium channel blocker, and a nutrient-rich matrix that has a sufficient amount of cell metabolites to sustain the metabolic needs of the harvested cells while incubating the cells for a period of at least 10 minutes, without producing detectable levels of lactate or substantially depleting the metabolic substrates of the cell.

1. Field of the Invention
This invention is related generally to the preservation of viable cells and in particular to a medium for conditioning and long term storage of viable cells.
2. Discussion of the Related Art
The preservation of viable cells which have been harvested from a donor source is of great importance and utility in the scientific and medical communities. Indeed, cells which have been harvested and preserved are routinely used in scientific research and development. For instance, preserved cells are often tested to aid in the development of medical treatments or to provide information on physical or chemical properties of the cells. Further, a collection of readily available viable cells allows scientists to conduct experiments at times which are suitable to laboratory availability or the researcher""s schedule. To be useful, the preserved cells must retain the integrity and viability of the cells at the time of harvest. Thus, the process of preserving the cells must not, in itself, damage or destroy the cells.
In conventional cryopreservation techniques, cells are harvested, suspended in a storage solution, then preserved by freezing. When the cells are to be used, they are thawed, for example, cells taken from human donor sources are brought back to the normal human body temperature (i.e., approximately 37xc2x0 C.), and then placed in a cell culture medium. Cryopreservation protocols subject the cells to a multitude of stresses and insults throughout the process of cell harvesting, freezing, and thawing. These stresses and insults can cause irreparable damage to the cell.
Ischemia, a lack of blood flow, occurs as soon as the life of the cell""s donor is terminated. Immediately thereafter, the cell experiences hypoxia, or oxygen deprivation, due to the lack of blood flow. Hypoxia causes anaerobic metabolism in normally aerobic cells. Anaerobic metabolism produces toxic byproducts, such as the build-up of lactic acid (acidosis). Some of the byproducts of anaerobic metabolism produce oxygen free-radicals that damage or destroy the cells when the cells are reoxygenated. Accordingly, prior to taking a tissue sample, the temperature of the donor source is reduced such that metabolic activity in the cells of the donor source is minimized. Reduction of temperature of the donor source reduces the energy state of the cells which aids in reducing the affects of ischemia and hypoxia. Typically, the temperature of the donor source is lowered to 4xc2x0 C. Although some residual metabolic activity exists in the cells at 4xc2x0 C., 4xc2x0 C. is about the lowest temperature available which does not cause the formation of ice crystals on the cells.
The cells are typically isolated from the tissue sample by addition of a hydrolytic enzyme. The hydrolytic enzyme deteriorates the extracellular tissue structure, thus causing the release of the desired cells. Unfortunately, the hydrolytic enzyme also harms the isolated cells. Some of the cells are destroyed during isolation. Other cells are weakened by exposure to the hydrolytic enzyme. It is believed that cells weakened by such enzymatic insult are less viable.
Once the cells are harvested, the cells are suspended in a storage solution which is also, typically, at 4xc2x0 C. One example of a widely used cell storage medium is Dulbecco""s Modified Eagle Medium (xe2x80x9cDMEMxe2x80x9d), an aqueous solution containing 10 wt. % fetal calf serum and low levels of glucose. DMEM is intended to provide support for the minimal metabolic activity which occurs just before the cells are frozen and just after the cells are brought to normal body temperature. Because cells are frozen as soon after harvest as possible, in order to completely arrest cell metabolism, the amount of glucose needed to support metabolic activity is quite low.
The harvested cells can also be harmed by the initial freezing and the subsequent thawing of the cell suspension. The cell membranes can be damaged primarily due to the rapid change in osmotic pressure that results when liquid inside or outside the cell is frozen or thawed. Freezing and thawing of the cell suspension causes a dramatic change in the concentration of liquid on one side of the membrane relative to the other. The dramatic change in concentration creates an osmotic pressure differential. The transmembrane pressure differential causes liquid to flow into the cell or liquid in the cell to flow out of the cell to reach equilibrium osmotic pressure. When excess liquid flows into a cell, the cells burst. When too much liquid leaves a cell, the cell shrivels and dies.
It is known to add cryopreservatives to a cell storage medium, such as DMEM, to prevent cell damage during freezing. Cryopreservatives include dimethyl sulfoxide (DMSO), glycerol, propylene glycol, and other large molecules with a high bonding affinity to water. Cryopreservatives are absorbed into the cells and have sufficient size that they are not likely to be rapidly transported across the membrane. Thus, when osmotic pressures change, the water remains bound to the cryopreservative and is stabilized to the change in transmembrane osmotic pressure. Of all the cryopreservatives, DMSO is by far the most preferred because of its high bonding affinity to water. However, DMSO is toxic to cells if added when the cells are at normal body temperature, and it is generally rapidly added to the cells just before the cells are frozen, i.e., when the temperature of the cells has been lowered to approximately 4xc2x0 C. Furthermore, the cells must be carefully washed to remove DMSO after the cells are subsequently thawed to a temperature of about 4xc2x0 C.
In addition to the above-stated problems, current preservation protocols are limited in that they are not necessarily transferrable between samples. Indeed, the type of sample has, in part, dictated the requirements of the preservation technique such that the technique employed is dependent, in part, upon the sample to be stored. Examples of various techniques of freezing and thawing of different sample types are found, for example, in U.S. Pat. No. 4,004,975 to Lionetti et al., directed to freezing and thawing of human white cells; U.S. Pat. No. 4,890,457 to McNally et al., directed to the freezing and thawing of collagen-rich tissue, such as heart valves; and U.S. Pat. No. 4,965,185 to Grischenko et al., directed to the freezing and thawing of embryos, more specifically, mammal embryos.
U.S. Pat. No. 5,328,821 to Fischer et al. discloses a cryopreservation solution for tissue slices. The solution contains (a) glucose and (b) a cryopreservative. Other ingredients include (c) impermeates, such as potassium gluconate, potassium saccharate, and mannitol, to prevent or minimize hypothermic induced cell swelling, (d) hydrogen ion buffers, such as a phosphate, (e) adenosine, an ATP precursor for the regeneration of high energy phosphate compounds, (f) free-radical inhibitors, such as allopurinol and mannitol, (g) reducing agents, such as glutathione, (h) inorganic salts, such as KCl, MgSO4, MgCl, NaHCO3, and KHCO3, (i) vitamins, such as vitamin E and vitamin C, (j) hormones, such as dexamethasone and insulin, (k) calcium channel blockers, such as verapamil, and (1) acid generating substrates, such as succinate, fructose and glucose. One of the drawbacks of the cell cryopreservation solution described in the Fischer et al. patent is that its use is limited to cryopreservation of tissue slices. Consequently, the utility of the solution disclosed in the Fischer patent has unproven effectiveness with harvested cells that have been weakened because they have been isolated by treatment with a hydrolytic enzyme.
Although some cryopreservation protocols have altered the conventional methods, these altered methods have failed to address all of the above mentioned problems. For instance, U.S. Pat. Nos. 5,171,660 and 5,424,207, both to Carpenter et al., describe an alternative to the immediate freezing of tissue samples. These patents give examples of placing heart leaflets in DMEM and then preincubating the tissue, for from about 5 minutes to about 24 hours, at a temperature of from about 27xc2x0 C. to about 42xc2x0 C. The preincubation is said to assure that the metabolic energy status and functional capacity of the tissue are restored when the tissue is thawed.
In U.S. Pat. No. 4,559,298 to Fahy, directed to vitrification of biological material, the cryopreservative is introduced and removed in step-wise concentrations. Specifically, the method in Fahy uses step-wise concentrations of greater than 10% per step. The large step-wise additions are aimed at inhibiting re-establishment of the isotonic volume of the cells prior to vitrification, i.e., osmotic equilibrium of the cells is not desired. Further, despite the step-wise addition and removal of a cryopreservative, intra-cellular concentrations are about 30% which is too high of a concentration and is not acceptable for some sample types, such as, for example, eukaryotes and aerobic prokaryotes. In U.S. Pat. No. 4,890,457 to McNally et al., which is directed toward collagen-rich tissue, the cryopreservative, DMSO, is removed in a 2.5% step-wise concentration. Nonetheless, the cryopreservative is not introduced in the same gradual step-wise concentrations, thus, potentially introducing cell stresses prior to freezing.
Thus, there remains a need for a generally applicable method for cell cryopreservation that more effectively maintains the integrity, viability and function of all types of cells during the cryopreservation process, more specifically, eukaryote, and aerobic prokaryote cells. The present invention satisfies these and other needs and provides further related advantages.
The present invention is a universally-adaptable cell preconditioning and storage medium that can be used for the effective cryopreservation of cells at temperatures less than 4xc2x0 C. The aqueous medium contains adenosine, a calcium channel blocker, and a nutrient-rich matrix that has a sufficient amount of cell metabolites to sustain the metabolic needs of the harvested cells while incubating the cells, generally at a temperature of from about 35xc2x0 C. to about 38xc2x0 C., preferably, about 37xc2x0 C. for a period of at least 10 minutes, preferably about 25 minutes, without producing detectable levels of lactate or substantially depleting the metabolic substrates of the cell.
Adenosine is included in the cell medium, typically in a concentration ranging from about 2.7 mM to about 3.6 mM. Preferably, the adenosine concentration ranges from about 2.9 mM to about 3.1 mM, and, more preferably, is about 3.0 mM. The adenosine is rapidly converted by the cells into adenosine triphosphate to supply immediate energy to the cells during preconditioning. The medium can also include other cell energy sources, such as saccharides like glucose, or metabolites of glucose, such as pyruvate.
A calcium channel blocker is included in the cell medium to prevent calcium-regulated membrane transport of the adenosine. An example of a preferred calcium channel blocker is verapamil. In one embodiment, verapamil is added to the cell medium in an amount ranging from about 0.04 mM to about 0.07 mM. It is added preferably in an amount ranging from about 0.05 mM to about 0.06 and more preferably in an amount of about 0.05 mM.
The other cell metabolites include nutrients that are easily absorbed into the cells to be preserved. Representative nutrients include one or more amino acids selected from alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine. Additionally, the cell metabolites. preferably include one or more vitamins selected from the group comprising pantothenate, choline chloride, folic acid, inositol, niacinamide, pyridoxal, riboflavin, and thiamine. The concentration of the amino acids is chosen to match the amino acid concentration found in the healthy cytoplasm of the cells to be preconditioned. Alternatively, the concentration of amino acids in the medium is chosen to be proportional to the metabolic needs of the cells during normal cell metabolism.
In some embodiments, the cell medium includes an inorganic salt. Suitable salt-forming inorganic anions include chloride, phosphate, sulfate, and selenite. Suitable salt-forming inorganic cations include sodium, potassium, magnesium, copper, and zinc cations. And in some embodiments, the cell medium has a concentration of inorganic salts substantially equal to the concentration of inorganic salts found in the in vivo donor cells.
Also in some embodiments, the cell cryopreservation medium contains at least one hormone. Representative hormones include insulin, and preferably bovine pancreas insulin; dexamethasone; leutropic hormone and preferably sheep leutropic hormone; transferrin and preferably human transferrin; somatropin; linoleic acid; fetal bovine serum.
In some embodiments, the medium also contains a cryopreservative for protecting the cells during freezing and thawing. Preferably, the cryopreservative is DMSO.
It is also preferable for the medium to include a oxygen free radical scavenger to protect the cells from oxygen free radicals produced during reoxygenation after storage. Most preferably, the oxygen free radical scavengers are allopurinol and/or glutathione. Alternatively, the cell salvage medium comprises glycine, glutamine, glutamic acid, and cysteine, proteins that are rapidly converted by the cell into glutathione.
The cell medium preferably is buffered with a mild buffer solution having a content and concentration such that the cell medium has a first pH that ranges from about 7.3 to about 7.5 at a temperature above 35xc2x0 C. and has a second pH ranging from about 6.3 to about 6.6, preferably form about 6.4 to about 6.5, and most preferably about 6.4, at a temperature below about 4xc2x0 C. A suitable buffer includes a sodium carbonate buffer, an N-[Hydroxyethyl]piperazine-Nxe2x80x2[2-ethananesulfonic acid] (xe2x80x9cHEPESxe2x80x9d) buffer or a combination of the two. Overall, the concentration of all of the components preferably create a solution that is slightly hyperosmolar.
The present invention is also directed to a preserved cell sample, that includes a sample of eukaryotic or prokaryotic cells, suspended and frozen, preferably at the boiling point of liquid nitrogen, in the cell cryopreservation medium, as well as to a kit for preserving a sample of cells comprising a storage vessel and the cell cryopreservation and cryopreservation medium. In some embodiments, the kit further includes instructions to incubate cell at 37xc2x0 C. for a period ranging from about 10 minutes to about 1 hour and preferably about 25 minutes prior to storing the cells at a temperature below 4xc2x0 C. Preferably, the kit also includes an oxygen source for oxygenating the cell preconditioning and cryopreservation and medium during the preconditioning. Most preferably, the kit includes instructions to oxygenate the solution with a gas having an oxygen content of no less than 80 vol. % while the cells are incubated at 37xc2x0 C.
The present invention is a universally-adaptable, aqueous cell preconditioning and cryopreservation medium useful for preserving cells at temperatures less than 4xc2x0 C. and in some embodiments less than 0xc2x0 C. The same medium is used to first precondition the cells thereby effectively reinvigorating cells damaged by harvesting from a donor source. Unlike conventional cell storage media, the inventive cell medium is capable of sustaining aerobic metabolism for a period of at least 10 minutes, preferably at least about 25 minutes, without producing detectable levels of lactate or substantially depleting the metabolic substrates of the cell. After preconditioning, the same cell media is used as an effective medium for cryopreservation of the cells. Furthermore, the cell medium also can be used after storage during reconditioning and reoxygenation of the preserved cells.
The cell medium contains adenosine, typically in a concentration ranging from about 2.7 mM to about 3.6 mM. Preferably, the adenosine concentration ranges from about 2.9 mM to about 3.1 mM, and, more preferably, is about 3.0 mM. Adenosine is rapidly converted by cells into adenosine triphosphate. The adenosine triphosphate is a cell energy source immediately available to promote cell growth and regeneration during preconditioning.
The cell medium can also include other cell energy sources, such as saccharides. Any saccharide, such as glucose, or metabolite of the glycolytic pathway, such a pyruvate, a metabolite of glucose, can be added to the cell cryopreservation medium as a potential energy source. The cell medium of one embodiment contains glucose in an amount ranging from about 18 mM to about 24 mM. Preferably, the solution contains glucose in an amount ranging from about 19 mM to about 21 mM, and most preferably about 20 mM. The cell medium of another embodiment contains sodium pyruvate in an amount ranging from about 0.9 mM to about 1.1 mM, preferably, about 1.0 mM.
The cell medium also includes a calcium channel blocker to prevent the calcium-regulated export of adenosine from the cell. This allows higher levels of adenosine in the cell which fortifies the cell with rapidly available energy. An example of a suitable calcium channel blocker is verapamil. In one embodiment, verapamil is added to the cell medium in an amount ranging from about 0.04 mM to about 0.07 mM. It is added preferably in an amount ranging from about 0.05 mM to about 0.06 and more preferably in an amount of about 0.05 mM.
Importantly, the cell medium contains various cell metabolites, such as nutrients that are easily absorbed into the cells during preconditioning. For example, the cell medium preferably contains one or more amino acids. Since each of the amino acids can be absorbed by the cell and consumed during the cell""s normal metabolism, it is preferable to have a concentration of all amino acids in the cell medium. However, it is believed that the addition of any amino acid will serve to strengthen the cell during preconditioning, even if other amino acids are not present.
The concentration of the amino acids is chosen to match the amino acid concentration found in the healthy cytoplasm of the cells to be preconditioned. Alternatively, the concentration of amino acids in the medium is chosen to be proportional to the metabolic needs of the cells during normal cell metabolism. Some amino acids are used more frequently and should be present in higher amounts.
L-alanine is preferably added in an amount ranging from about 0.09 mM to about 0.11 mM and more preferably added in the amount of about 0.10 mM. Arginine is preferably added in an amount ranging from 0.6 mM to about 0.8 mM and is more preferably added in an amount of about 0.7 mM. Asparagine and/or aspartic acid are preferably added in a total amount ranging from about 0.9 mM to about 1.1 mM and most preferably added in an amount of about 1.0 mM. In one embodiment, the ratio of asparagine to aspartic acid is 10:1.
Cysteine is preferably added in an amount ranging from about 0.9 mM to about 1.1 mM and most preferably added in an amount of about 1.0 mM. Glutamine and/or glutamic acid are preferably added in a total amount ranging from about 2.7 mM to about 3.3 mM and more preferably added in an amount of about 3.0 mM. The ratio of glutamine to glutamic acid is about 2:1 in one embodiment of the present invention. Glycine is preferably added in an amount ranging from about 0.9 mM to about 1.1 mM and more preferably added in an amount of about 1.0 mM. Histidine is preferably added in an amount ranging from about 0.25 mM to about 0.30 mM and more preferably added in an amount of about 0.28 mM. Isoleucine is added in an amount preferably ranging from about 0.7 mM to about 0.9 mM and more preferably added in an amount of about 0.8 mM. Leucine is added in an amount ranging from 0.7 mM to about 0.9 mM and more preferably added in an amount of about 0.8 mM.
Lysine is added in an amount ranging from about 0.7 mM to about 0.9 mM and more preferably added in an amount of about 0.8 mM. Methionine is added in an amount ranging from 0.18 mM to 0.22 mM and more preferably added in an amount of about 0.20 mM. Phenylalanine is added in an amount ranging from about 0.35 mM to 0.45 mM and more preferably added in an amount of about 0.40 mM. Proline is added in an amount ranging from about 0.09 mM to about 0.11 mM and more preferably added in an amount of about 0.10 mM. Serine is added in an amount ranging from about 0.35 mM to about 0.45 mM and more preferably added in an amount of about 0.40 mM. Threonine is added in an amount from about 0.35 mM to about 0.45 mM and more preferably added in an amount of about 0.40 mM. Tryptophan is added in an amount ranging from 0.12 mM to about 0.15 mM and more preferably added in an amount of about 0.13 mM. Tyrosine is added in amount ranging from about 0.55 mM to about 0.65 mM and more preferably added in an amount of about 0.60 mM. Valine is added from about 0.7 mM to about 0.9 mM and more preferably 0.8 mM.
Additionally, the cell media preferably contains one or more vitamins selected from the group comprising pantothenate, choline chloride, folic acid, inositol, niacinamide, pyridoxal, riboflavin, and thiamine. Vitamins are supplied to fortify the cell after cell harvesting. They serve to replenish vitamins lost during treatment with the hydrolytic enzyme or that might have been deficient in the donor source of the cells.
While it is preferred that all of the known vitamins are added to the cell medium. the addition of vitamins are optional. In one embodiment, the following vitamins are added in the stated amounts. Pantothenate is added in an amount ranging from about 0.003 to about 0.009 mM and more preferably about 0.008 mM. Choline chloride is preferably added in an amount ranging from about 0.026 mM to 0.032 mM and more preferably about 0.029 mM. Folic acid is added in an amount ranging from about 0.008 mM to 0.010 mM and more preferably about 0.009 mM. Inositol is added in an amount ranging from about 0.036 mM to 0.044 mM and more preferably about 0.040 mM. Niacinamide is added preferably in an amount ranging from about 0.030 mM to 0.036 mM and more preferably about 0.033 mM. Pyridoxal is added in an amount ranging from about 0.018 mM to 0.022 mM and more preferably about 0.020 mM. Riboflavin is added in an amount ranging from about 0.0009 mM to 0.0011 mM and more preferably about 0.001 mM. Thiamine is added in an amount ranging from about 0.011 mM to 0.013 mM and more preferably about 0.012 mM.
In some embodiments, the cell medium contains one or more inorganic salt. The salt is added to the medium to prevent the cell reserves from being depleted. Since the inorganic ions forming the salts are very small, they readily pass through the cell membrane and are lost from the cell. Suitable inorganic anions include chloride, phosphate, sulfate, or selenite ions. Suitable inorganic cations include sodium, potassium, magnesium, copper, or zinc ions. In these embodiments, the cell medium preferably has a concentration of inorganic ions substantially equal to the intercellular concentration of the ions in a cell in vivo.
In preferred embodiments, the cell medium contains inorganic salts in an amount sufficient to create a slightly hypertonic medium, i.e., is slightly hypertonic compared to the osmolarity of the cell cytoplasm. The cells shrink slightly when in such a slightly hypertonic medium. Thus, there is less stress on the membrane which benefits the cell during cold preservation and cryopreservation. Accordingly, in a preferred embodiment, the cell medium has an osmolarity of approximately 330 mOsml/L.
The following concentration of salts have been found effective in maintaining appropriate ionic levels. Sodium chloride is added preferably in an amount ranging from 110 mM to about 120 mM and more preferably in an amount of about 115 mM. Potassium chloride is added preferably in an amount ranging from approximately 4.75 mM to 5.25 mM and more preferably in an amount of about 5 mM. Potassium phosphate is added preferably in an amount ranging from about 2.85 mM to about 3.15 mM and more preferably in an amount of about 3 mM. Magnesium sulphate is added preferably in an amount ranging from 1.15 mM to about 1.25 mM and more preferably in an amount of approximately 1.2 mM.
Copper sulfate is available in a hydrated form (CuO4.H2O) and is added in an amount ranging from approximately 8.5 mM to approximately 9.4 mM and more preferably 8.9 mM. Zinc sulphate is available in a hydrated form having a formula (ZnSO4.H2O) and is added in an amount ranging from 4.2xc3x9710xe2x88x928 mM to about 4.6xc3x9710xe2x88x928 mM and more preferably 4.4xc3x9710xe2x88x928 mM. Sodium selenite (Na2SeO3) is preferably added in an amount ranging from about 2.8xc3x9710xe2x88x926 through 3.2xc3x9710xe2x88x926 mM and more preferably 3.0xc3x9710xe2x88x926 mM.
Also in some embodiments, the cell cryopreservation medium contains at least one hormone. Suitable hormones include insulin, and preferably bovine pancreas insulin; dexamethasone; leutropic hormone and preferably sheep leutropic hormone; transferrin and preferably human transferrin; somatropin; linoleic acid; and fetal bovine serum.
Because the cell suspension is to be frozen, a cryopreservative is preferably added to the cell medium. Suitable cryopreservatives include DMSO, glycerol, propylene glycol, and other large molecules with a high bonding affinity to water, with DMSO being most preferred. Since DMSO is potentially toxic, it is not added to the cell medium until after the cell medium has been combined with the cells and the resulting suspension cooled to a temperature below that which DMSO adversely affects the cells. It is preferred that DMSO be added to the suspension at a temperature at or below about 4xc2x0 C. In one embodiment of the invention, the DMSO has a concentration ranging from about 8 vol. % to about 15 vol %. Preferably, the concentration of DMSO is about 12 vol. %.
It is also preferable for the cell medium to include an oxygen free-radical scavenger to protect the cells from any oxygen free-radicals that may be present during reoxygenation after storage. Oxygen free-radicals are highly reactive and cause considerable damage to a cell. Typically, oxygen free-radical scavengers are large organometallic molecules that readily react with the oxygen free-radicals, before the radicals can damage the cell.
Preferred oxygen free-radical scavengers include allopurinol and/or glutathione. In one embodiment, allopurinol is added in an amount ranging from about 0.9 mM to about 1.2 mM and is added more preferably in an amount of about 1 mM. In another embodiment, glutathione is added in an amount ranging from about 2.7 mM to about 3.6 mM. It is added preferably in an amount ranging from about 2.9 mM to about 3.1 mM and is added more preferably in an amount of about 3.0 mM.
Alternatively, the cell produces glutathione naturally when glutathione levels are low. Glutathione is formed from three amino acids, namely glycine, glutamate, and cysteine. Thus, the oxygen free radical scavenger function can be satisfied or, at least, supported by a medium that combines these three amino acids.
The cell medium of one embodiment is buffered. The normal pH of a cell is typically about 7.4 but can fluctuate under normal situations. In a healthy cell in vivo the pH will fall within a first range of from about 7.3 to about 7.5 without dramatically affecting the performance of the cell. During cell cooling, the pH of the cell becomes more acidic. As the cell becomes acidic, the enzymes of the cell do not function normally which arrests the cell metabolism and other enzymatic activity.
Conventional cell cryopreservation media are buffered so as to maintain the pH of the medium at the pH of natural extracellular fluid during the entire preconditioning and cryopreservation process. In contrast to such conventional media, in some embodiments, the buffer included with the inventive cell medium allows the pH of the medium to drop from about 6.3 to about 6.6, preferably form about 6.4 to about 6.5, and most preferably about 6.4, when the cell suspension is cooled to temperature of about 4xc2x0 C.
Preferred buffers include a sodium carbonate buffer, an N-[Hydroxyethyl]piperazine-Nxe2x80x2[2-ethananesulfonic acid] (xe2x80x9cHEPESxe2x80x9d) buffer or a combination of the two. In accordance with a most preferred embodiment, the amount of sodium bicarbonate ranges from about 22.5 mM to about 27.5 mM, preferably from about 24 mM to about 26 mM and, more preferably, about 25 mM, while the amount of HEPES ranges from about 9 mM to about 11 mM and more preferably about 10 mM.
When, the cell medium is combined with the cell samples at 37xc2x0 C., the pH of the mixture should be within the above stated first range of from about 7.3 to about 7.5 and should preferably be as close to 7.4 as possible. Then, as the sample is cooled, the pH will drop. When the pH is 4xc2x0 C., the pH should fall within the above stated second range of from about 6.3 to about 6.6, preferably form about 6.4 to about 6.5, and most preferably about 6.4. If the pH does not fall within the second range or it is desired that the medium have a pH closer to 6.4, the medium can be titrated with a mild sodium carbonate solution or a mild carbonic acid solution to adjust the pH to the desired value. One benefit of the inventive medium is that the pH will return to a pH close to 7.4 when the cells are warmed to 37xc2x0 C.
The method of using the cell medium is described in copending application by the inventors of the present patent application and which is filed the same day as the present application. This application is Ser. No. 09/168,366, now U.S. Pat. No. 6,140,123 and is fully incorporated by reference into the present application.
The method begins by taking harvested eukaryotic or prokaryotic cells and suspending the cells in the cell medium, while maintaining the temperature at about 35-40xc2x0 C., and more preferably about 37xc2x0 C. The medium is oxygenated by bubbling oxygen through the solution using a gas having an oxygen content of no less than 80 vol. %. In one embodiment, the medium is saturated at a pressure exceeding atmospheric pressure. The cells are preconditioned in this matter for a period ranging from about 10 minutes to about 48 hours. Preferably, the cells are preconditioned for a period ranging from about 10 minutes to about 2 hours, and more preferably about 25 minutes.
The cell suspension is then cooled to about 4xc2x0 C. DMSO is slowly added to the suspension until the amount of DMSO reached has a concentration ranging from about 8 vol. % to about 15 vol %., preferably about 12 vol. %. The suspension is placed in cryo-vials for freezing. Cryo-vials containing the suspension are first placed in a freezer that maintained at xe2x88x9270xc2x0 C. for about two hours to allow the water inside the cell to penetrate into extracellular space. Then the cryo-vials are transferred to the vapor phase of a liquid nitrogen tank for 10-24 hours. Thereafter, the cryo-vials are immersed in liquid nitrogen for long term storage at xe2x88x92196xc2x0, the boiling point of liquid nitrogen.
The cells are recovered by placing the frozen suspension in a water bath maintained at 37xc2x0 C.-42xc2x0 C. and gently agitating until the temperature of the cell suspension reaches 37xc2x0 C. The cell suspension is then transferred into a round bottom glass tube, spun to separate the cells from a supernatant, and the supernatant removed. Next the cells are washed with additional cell cryopreservation medium, including DMSO, and having an osmolarity of 1500 mOsml/l . The cell medium is slowly added to the cells and the cells resuspended. After resuspension, the cells are spun the supernatant again removed, and the cells recovered. The cells are then washed with an oxygenated cell cryopreservation medium that includes DMSO but has an osmolarity of 900 mOsml/l. Finally, the cells are resuspended in a cell cryopreservation medium having no DMSO, spun, and recovered. The cells are then ready for use.
The present invention also comprises a kit for storage of cells. The kit includes a cell medium as described above with a vessel for containing the cells. Also included in the kit is a set of instructions. The instructions include directions on using the cell medium in accordance with the principles of the present invention. In one embodiment, the instructions direct the user to oxygenate the cell medium and precondition the cells at a temperature of approximately 37xc2x0 C. for a length of time ranging from about 10 minutes to about 48 hours. According to this embodiment, the kit preferably includes a source of oxygen and an oxygen delivery device. The oxygen delivery device enables the medium to be saturated with oxygen.
The instructions according to another embodiment of the invention, provide directions to measure the pH of the medium when the medium is at a temperature of about 4xc2x0 C. The directions further include instructions on titrating the medium to a pH of about 6.3 to about 6.5, preferably about 6.4.
The present invention also includes a preserved cell sample that includes a sample of eukaryotic or prokaryotic cells suspended in a cell medium according to the principles of the present invention. The cell sample is preferably kept at a temperature below 4xc2x0 C. In another embodiment the cell sample is frozen and is preferably frozen at the boiling point of liquid nitrogen.
The following examples are included to further illustrate the invention. They are not limitations thereon.

Cell preconditioning and cryopresevation medium


A cabinet has a tread base rotatably connected to be oriented in an exercise position extending outwardly and in a stored position extending inwardly secured within the enclosure of the cabinet. The underside of the tread base may be configured to provide a suitable aesthetic exterior surface. A latching arrangement provided to secure the tread base within the enclosure in the second or stored position. Elevation structure and motor structure are provided to elevate the tread base when in the first position and to power the endless belt of the tread base when in the first position. The elevation structure may be operated to vary the inclination of the tread base when in the first position. The underside of the tread base has a decorative panel and functions as a door for the cabinet. The elevation structure may include an electrically driven rack and pinion as well as a gas cylinder system.

1. Field of the Invention
This invention relates to treadmills and, more particularly, the treadmills that have a tread base which is reorientable from a first exercise position to a second storage position within the cabinet, which cabinet includes latching structure for latching the tread base in the cabinet.
2. State of the Art
Exercise treadmills typically include a frame having a left side and a right side spaced apart from the left side and in general alignment therewith. A rigid deck is also typically secured between the left side and the right side. A front roller and rear roller are typically connected to and extend between the left side and the right side forward and rearward of the deck. An endless belt is trained around the front roller and the rear roller. The user exercises on the treadmill by walking, jogging or running on the endless belt on top of a deck underlying the endless belt.
Typical treadmills also include surface engaging structure to support the treadmill on a support surface. The surface engaging structure typically includes feet positioned proximate the rear of the treadmill and feet positioned proximate the front of treadmill. The front feet or the rear feet may be operable to vary the inclination of the treadmill with respect to the support surface. For example, U.S. Pat. No. 4,913,396 (Dalebout et al.) discloses a system for varying or adjusting the incline of a treadmill through the use of a pneumatic cylinder. U.S. Pat. No. 4,998,725 (Watterson et al.) discloses an alternate arrangement for varying the inclination of a treadmill.
Treadmills also include handles or other upright structure such as that shown in U.S. Des. Pat. No. 304,849 (Watterson), U.S. Des. Pat. No. 306,468 (Watterson), U.S. Des. Pat. No. 306,891 (Watterson), U.S. Des. Pat. No. 316,124 (Dalebout et al.), U.S. Des. Pat. No. 318,699 (Jacobson et al.), U.S. Des. Pat. No. 323,198 (Dalebout et al.), and U.S. Des. Pat. No. 323,199 (Dalebout et al.). Reorientation or repositioning of the upright structure to facilitate storage has also been disclosed. U.S. Pat. No. 5,102,380 (Jacobson et al.) shows a treadmill in which a center post may be reoriented from an upright operating position to a lowered position in alignment with the treadmill and with the belt or deck. U.S. Des. Pat. No. 211,801 (Quinton) shows a treadmill with structure that may be moved from an upright position to a lowered position in general alignment with the treadmill belt or deck. U.S. Patent Des. 207,541 shows a treadmill that may be reoriented from a horizontal operating condition to an upright storage position.
Storing exercise equipment inside a cabinet or other enclosure is also known. U.S. Pat. No. 4,300,761 (Howard) shows an exercise bench which may be repositioned interior a cabinet for purposes of storage. U.S. Pat. No. 3,741,538 (Lewis et al.) shows an arrangement in which the exercising structure is folded upright for storage against a wall surface. U.S. Pat. No. 3,642,279 (Cutter) shows a treadmill in which an upright structure may be reoriented to be generally in alignment with the endless belt for purposes of reorienting the treadmill to an upright or storage configuration.
U.S. Pat. No. 4,679,787 (Guilbault) shows a bed combined with a treadmill or rolling structure in which the bed is positioned over the top of the treadmill or rolling structure for purposes of storage. U.S. Pat. No. 4,757,987 (Allemand) shows a treadmill which may be reconfigured into a compact foldable structure which may, in turn, be transported. U.S. Pat. No. 4,066,257 (Moller) shows a treadmill positioned within a cabinet that is secured to a wall and reoriented between an upright stored position and an extended or horizontal position for use.


A method for generating acoustic waves, the method having the steps of: extending a tine from a support structure so that a proximal end of the tine is attached to the support structure and a distal end of the tine is uninhibited; positioning an oscillator so as to be supported by the support structure and to mechanically communicate with the tine; and oscillating the tine with the oscillator.

This invention relates to cleaning of screens, gravel packs and formations in producing well having installed production tubing. In particular, this invention relates to methods that provide downhole acoustic cleaning.
In any typical hydrocarbon well, damage to the surrounding formation can impede fluid flow and cause production levels to drop. While many damage mechanisms plague wells, one of the most pervasive problems is particles clogging the formation pores that usually allow hydrocarbon flow. These clogging particles can also obstruct fluid pathways in screens; preslotted, predrilled, or cemented and perforated liners; and gravel packs that may line a well. Clogging particles may even restrict fluid flow in open-hole wells. Drilling mud, drilled solid invasion, or even the porous formation medium itself may be sources for these particles. In particular, in situ fines mobilized during production can lodge themselves in the formation pores, preslotted liners, screens and gravel packs, sealing them to fluid flow. Referred to as the "skin effect," this damage is often unavoidable and can arise at any stage in the life of a typical hydrocarbon well. The hydrocarbon production industry has thus developed well-stimulation techniques to repair affected wells or at least mitigate skin-effect damage.
The two classic stimulation techniques for formation damage, matrix acidizing and hydraulic fracturing, suffer from limitations that often make them impractical. Both techniques require the operator to pump customized fluids into the well, a process that is expensive, invasive and difficult to control. In matrix acidizing, pumps inject thousands of gallons of acid into the well to dissolve away precipitates, fines, or scale on the inside of tubulars, in the pores of a screen or gravel pack, or inside the formation. Any tool, screen, liner or casing that comes into contact with the acid must be protected from its corrosive effects. A corrosion inhibitor must be used to prevent tubulars from corrosion. Also, the acid must be removed from the well. Often, the well must also be flushed with pre- and post-acid solutions. Aside from the difficulties of determining the proper chemical composition for these fluids and pumping them down the well, the environmental costs of matrix acidizing can render the process undesirable. Screens, preslotted liners and gravel packs may also be flushed with a brine solution to remove solid particles. While this brine treatment is cheap and relatively easy to complete, it offers only a temporary and localized respite from the skin effect. Moreover, frequent flushing can damage the formation and further decrease production. In hydraulic fracturing, a customized fluid is ejected at extremely high pressure against the well bore walls to force the surrounding formation to fracture. The customized gel-based fluid contains a proppant to hold the fractures open to fluid flow. While this procedure is highly effective at overcoming near-borehole skin effects, it requires both specialized equipment and specialized fluids and therefore can be costly. Fracturing can also result in particle deposition in the formation because the gels involved may leave residue in the vicinity of the fractures.
The hydrocarbon production industry developed acoustic stimulation as an alternative to the classic stimulation techniques. In acoustic stimulation used for near-well bore cleaning, high-intensity acoustic waves transfer vibrational energy to the solid particles clogging formation pores. The ensuing vibrations of the solid particles loosen them from the pores. Production-fluid flow out of the formation in producing wells causes the solid particles to migrate out of the pores, clearing the way for greater production-fluid flow. In injection wells, either injection-fluid flow or production-fluid flow can flush the loosened solid particles from the pores. Acoustic stimulation may also be used to clean preslotted and predrilled liners, screens and gravel packs. Near-well bore cleaning by acoustic stimulation has shown great promise in laboratory experiments, and the industry has developed several tools using this technique for use in real-world wells.
One type of acoustic tool that has been described employs an oval configuration. In an oval configuration, the tool has a cylindrical housing with a set of piezoelectric drivers mounted a various locations around the side walls of the housing. Separate control signals are used to activate the individual piezoelectric drivers according to a desired mode of operation. According to one exemplary oval mode configuration, four divers are position equidistant around the circumference of the housing. A four divers make up two sets with two drivers in each set. In each set of drivers, the drivers are positioned exactly opposite from each other on the housing. During operation, a first set of drivers is activated to pull outwardly on the sidewall of the housing, while the second set of drivers is activated to push inwardly on the housing. According to separate control signals, the drivers are then activated to push/pull in the opposite directions. In particular, the first set of drivers is activated to push inwardly on the sidewall of the housing, while the second set of drivers is activated to pull outwardly on the housing. As the piezoelectric drivers vibrate, the housing flexes between an oval having its major axis along the first set of drivers and an oval having its major axis along the second set of drivers. The radiated energy is strongest at the antinodes (the wall locations intersected by the diameters having maximum deflection. Midway between the antinodes on the wall are locations that remain stationary during vibration. The stationary points are nodes. Depending on the wall thickness and the material properties of the housing and the size of the piezoelectric drivers, the drivers may be activated at a frequency equal to a harmonic frequency of the housing so that the amplitude of deflection is maximized.
The lowest frequency oval mode has four antinodes and four nodes. Higher-order oval modes have even integer numbers of antinodes and nodes (six, eight, etc.). While it is theoretically possible to operate a tool with any order of oval mode resonance by driving the tool at the resonant frequency of that order of mode, practical limits on electrical impedance matching and driver placement constrain the number of useful driving frequencies.

Acoustic stimulation method with axial driver actuating moment arms on tines

Shell International Exploration and Production B.V.


A method for processing video image data for display during interactive game play is provided. During a game play session, processing of one or more images of the game play session is performed to adjust scene representation of objects at a first distance relative to objects at a second distance. During the game play session, the method generates a sharp image for a scene and produces a blur image of the scene. The method then generates a composited blend image of the sharp and blur images using data from z-dimension image data. The composited blend image has depth of field information provided by the z-dimension image data, and then rendering of the scene for display during the interactive game play. The method then repeats for the one or more images during the game play session.

1. Field of the Invention
This invention relates generally to computer graphics and, more particularly, to computer-produced display images with enhanced realism.
2. Description of the Related Art
Computers are being used to depict "virtual reality" worlds that do not exist anywhere except in a three-dimensional space maintained by the computer. Objects can "exist" in the virtual reality world and can move about in the coordinate space of the virtual reality. Such worlds are quite useful for simulations of real-world events where it is not practical to use real objects, such as laboratory investigations and event simulations, and are useful for entertainment purposes such as computer games and cinematic works (animation). The field of computer graphics strives to provide images depicting a computer's virtual reality world with greater realism.
A computer display image is specified as a combination of picture elements, each of which is called a pixel. The pixels in a display image specify a combination of red, blue, and green color information, much like a conventional television image is specified. Each pixel is associated with data specifying color intensity information for each red, blue, and green pixel of the image. The color intensity data is typically represented by an 8-bit data word. Most virtual reality simulations represent objects in a scene as data objects that have associated characteristics such as shape, size, position, and color. When an object is to be drawn, or rendered, on the computer display, a graphics processor determines an appropriate mixture of red, blue, and green pixel information for depiction of the image and generates video information for the correct mixture of red, blue, and green colors for each pixel. Display devices may have different-sized pixels with which images are produced. Many computer flat panel displays, for example, may have individual circular pixels each having a diameter of approximately 0.29 mm (0.0116 inch).
A computer graphics processor or display processor provides picture rendering processing for a computing device so that images created by a computer application program or other source of computer-generated pictures will be properly displayed. Computer graphics involves the creation, storage, and manipulation of models and images of objects based on pictorial synthesis of the objects from computer-based models. The creation, storage, and manipulation of the objects may occur in real time and may be an interactive process involving a computer user with an input device such as a keyboard, display mouse, controller, or touch-screen display panel. An important part of the picture rendering process involves image processing, in which the position and movement of objects in the images are carefully reproduced in two-dimensional and three-dimensional space.
For example, to determine what objects are being represented and what will be visible in the rendered or drawn image, a graphics processor maintains position information for all the pixels in a scene, representing the points of an object in the computer-drawn scene. Some of the position information is maintained in the form of a z-buffer for the image. The z-buffer for an image or frame of a scene is a set of data values, one data value for each pixel in the image, based on coordinates that determine the position of an object in the scene. That is, the z-buffer data is used to specify how far a pixel of an object is from the camera perspective. Thus, there is one z-buffer data entry for each pixel in a display image, and the graphics processor will maintain the data that specifies the position of that pixel in the computer model.
Each z-buffer data point may be represented by a data word, such as a 32-bit data word. See, for example, Section 1.5, "Hidden surface removal algorithm" at p. 22 in Advanced Animation and Rendering Techniques by A. Watt and M. Watt (ACM Press, 1992). The fidelity and detail of the computer image depends in part on the ability of the graphics processor to perform the necessary mathematical calculations on the object position information embodied in the z-buffer, and commercially available graphics processors are being continuously improved with respect to their mathematical processing capabilities and other image-processing power.
Computer-drawn virtual reality images typically have a different appearance from real images (such as photographs or video frames) of actual objects. One of the reasons for the discrepancy between computer images of virtual reality and images of actual physical objects is that virtual reality images do not realistically show expected depth of field information. Generally, depth of field refers to the changing amount of detail the human eye expects to perceive for objects in an image, depending on whether an object is close or far away from the viewer's perspective. For example, objects in a photograph that are farther away from the viewer's perspective will have fewer discernible image details and will be less distinct than objects that are closer to the viewer. Thus, far away objects have a "fuzzy" look and are not as sharp and clear as close up objects.
One of the reasons for the "cartoonish" appearance of most virtual reality images is because close up objects in the images typically are not sharper and have no more detail than far away objects, and far away objects do not appear any more fuzzy than close up objects. In other words, depth of field is constant throughout the virtual reality image. This is contrary to the appearance of "real world" images. Thus, a cartoon appearance results when discernible details of an object do not change in the expected manner when the object is closer or farther away in the image. A more realistic appearance would require close objects to have more detail and be sharper than objects that are farther away.
Some techniques have been used to provide enhanced depth of field information in computer image displays. For example, a stochastic sampling technique is used in distributed ray tracing to integrate depth of field information in a pre-rendered computer generated image. Another post-processing technique uses pixel intensity and z-buffer image depth data to determine the size and intensity distribution of the circle of confusion for each image point as it relates to its z-buffer value and the lens aperture being used. The intensity of each point in the output image is calculated as a weighted average of the intensities in the circles of confusion that overlap at each point. This technique is described by Potmesil and Chakravarty, referenced in Computer Graphics: Principles and Practice, Second Edition in C, by J. Foley et al. (Addison-Wesley Publishing Company, Inc., 1996) in Section 16.10 at 774–775. These techniques, however, are post-processing techniques and are not used to render images in a real time process. Thus, they are not suitable for any interactive use.
From the discussion above, it should be apparent that there is a need for realistic computer-drawn images with enhanced depth of field information. The present invention fulfills this need.

This patent is subject to a terminal disclaimer.

Image data processing using depth image data for realistic scene representation

Sony Computer Entertainment America Inc.


A semiconductor light emitting device capable of improving the light extraction efficiency while preventing deterioration of the light emission characteristic with time and a semiconductor light emitting device assembly including the semiconductor light emitting device are provided. The semiconductor light emitting device includes a semiconductor light emitting element containing a metal element, a cap portion formed from a material which contains a sulfur or halogen element and which is capable of transmitting the light from the semiconductor light emitting element, and a shielding film which is disposed between the semiconductor light emitting element and the cap portion, which transmits the light from the semiconductor light emitting element to the cap portion, and which separates the semiconductor light emitting element side and the cap portion side.

1. Field of the Invention
The present invention relates to a semiconductor light emitting device including a cap portion formed from a resin material and a semiconductor light emitting device assembly to be used for a light source device including the semiconductor light emitting device.
2. Description of the Related Art
In recent years, with respect to light emitting diodes (LEDs) including GaN based semiconductors or InGaN based semiconductors, so-called back emitting (flip chip type) LEDs have become in the mainstream in order to improve light extraction efficiency. In the flip chip type LED, a semiconductor layered structure including an active layer is disposed between a transparent substrate and a reflection electrode and, thereby, the light generated from the active layer is emitted from the back side (transparent substrate side).
FIG. 11 shows an example of a cross-sectional configuration of a known semiconductor light emitting device (LED device 101) including a flip chip type LED. In the LED device 101, an LED chip 102 which generates emitted light L101 is disposed on a sub-mount substrate 131, and electrodes (not shown in the drawing) in the LED chip 102 are electrically connected to lead frame electrodes 141A and 141B with bonding wires 142A and 142B. The sub-mount substrate 131 is bonded to a slug 132, which is a heat dissipation structure, with a thermally conductive adhesive 133. The slug 132 and a part of the lead frame electrodes 141A and 141B are covered with a case 143. The circumference of the LED chip 102 is also covered with a filler 154 and a cap 152 so as to be sealed against the outside.
For example, a highly flexible material, e.g., silicone gel, or a highly fluid material is used as the filler 154. On the other hand, for the cap 152, an epoxy resin or the like is used, and besides, resin materials have been proposed, as described in Japanese Patent Nos. 2989787, 3155925, 3439582, and 3491660, for example. When hard materials, e.g., epoxy based resins, are used, fillers also function as caps.

Semiconductor light emitting device and semiconductor light emitting device assembly


A computer-implemented user notification method includes displaying, in a status area near a perimeter of a graphical interface, a notification of a recent alert event for a mobile device, receiving a user selection in the status area, and in response to the receipt of the user selection, displaying, in a central zone of the graphical interface, detail regarding a plurality of recent messaging events for the mobile device.

More and more, people are on the run, using mobile communication devices to keep communicating. From mobile devices, people make and receive telephone calls, send and receive electronic mail, surf the web, and text with various friends and acquaintances.
When messages come in or when other events occur on a mobile device, it is customary for the device to make a noise signaling the event. Such an action derives from traditional telephones, which rang and still ring a bell when someone is calling. Such ringtones can now be customized depending on the identity of the caller for the incoming call. Also, a device may be switched to vibrate mode when silence is golden, such as at a meeting, a movie, or a play. For other sorts of incoming messages, such as e-mails, or for other events, the device may beep, vibrate, or provide some other form of alert.


A technique facilitates conveyance of equipment along a wellbore or other tubular structure. A tractor is provided with a plurality of wheels oriented to engage a surrounding wall. Rotation of the wheels drives the tractor and causes longitudinal movement of the tractor with respect to the surrounding wall via a tangential force created between each wheel and the surrounding wall. Each wheel comprises teeth having a wheel tooth geometry which enhances cooperation with the surrounding wall. For example, the wheel tooth geometry may be designed to cooperate with the tangential force to push debris out of the teeth of each wheel during rotation of the wheel along the surrounding wall. In some applications, the wheel tooth geometry is designed to present a plurality of raised, rounded surfaces which engage the surrounding wall with a low stress impact.

In many well applications, tractors are employed to facilitate movement of equipment along a wellbore. A tractor may be connected to the well equipment in a manner such that the tractor acts against a surrounding wellbore wall to apply a force which moves the equipment in a desired direction along the wellbore. Many tractors are designed with driving wheels which rotate while gripping the surrounding wellbore wall to move the tractor. Such tractors may be employed in a variety of downhole environments, including oil well environments which have high concentrations of paraffin or wax content, large amounts of built up scale, or other types of debris. The debris found in wellbore environments tends to clog teeth on the driving wheels which reduces the gripping capability of the driving wheels. In some of these applications, the casing or other tubing against which the tractor acts to move the equipment may comprise plastic coatings that can be damaged by the tractor.


Apparatus for determining which bulb or bulbs in a string of miniature incandescent light bulbs is burned out. The apparatus includes a socket adaptor with wire contacts at the base thereof for making conductive contact with both circuit contacts in the base of a selected bulb socket in the light circuit. Light emitting diodes are located within the adaptor body between each wire contact and a junction connected to one contact of a battery. The other contact of the battery is connected to both contacts of a female receptacle body. The male plug of the light circuit is inserted into the female receptacle of the socket adaptor, thus placing both ends of the string of bulbs in connective communication with one contact of the battery. The diodes are located in the socket adaptor body so that when either diode lights up, the direction in the light circuit of the inoperative bulb is indicated.

1. Field of the Invention
The present invention is concerned with an apparatus and method for testing strings of miniature incandescent light bulbs to locate inoperative bulbs. Strings of miniature incandescent light bulbs are extremely popular currently for various decorative purposes. One of the most common is for decoration of Christmas trees. The sets are usually strung in series with a minimum of 15 bulbs or more. Since the lamp filaments are generally 2.5 to 7 volts and in series, the total filament voltage should add up to 110 to 120 volts of common household current. Sets with large numbers of bulbs are generally divided into multiple sections in which the bulbs in each section are connected in series. When one bulb fails, a whole section fails to light and it is very frustrating and time consuming to locate and replace the failed bulb. Usually many bulbs have to be checked and replaced before finding the failed bulb.
While there are presently various apparatus available for testing individual bulbs there is no apparatus presently known which is inexpensive, simple to use and can be used to rapidly locate the failed bulb by removing one bulb and connecting the apparatus of the present invention to the bulb socket to determine if that is the failed bulb and if it is not, the direction on the string of bulbs to the location of the failed bulb.
2. Prior Art
U.S. Pat. No. 4,943,752, Todd. While this reference specifically discloses a Christmas tree lamp tester which is simple and utilizes a portable 9 volt battery, it fails to eliminate the need of testing multiple individual lamp bulbs, more or less blindly, since it gives no indication as to the direction of the failed lamp if the socket selected randomly is not the socket of the failed lamp. It uses a piezoelectric circuit suitable for testing Christmas tree lights and related devices. The device, however is suitable for testing only bulbs singularly by inducing a spark across a broken filament of the bulb.
U.S. Pat. No. 5,008,626, Boyd. Also discloses a portable DC miniature lamp tester which includes a translucent plastic body with an open socket for receiving the bayonet end of the lamp, and terminals connecting to a nine volt dry cell battery. This is specifically designed for testing light strings.
The general difficulties in testing Christmas tree lamps are discussed in column 1 of this patent which also refers to the Olin U.S. Pat. No. 3,725,780 which specifically discloses a Christmas tree lamp tester that utilizes a nine volt battery.
U.S. Pat. No. 5,047,721, Farley. Shows a detector for testing a string of lights; i.e. Christmas tree lights by providing means for testing lamps without removing the lamps from the sockets utilizing capacitor plates. Once again, no directional capability is disclosed.
U.S. Pat. No. 3,760,266, Ocasio, Tuman. Shows a simple Christmas tree light socket tester to determine which in a series of lights is burned out. Again, no directional capability is disclosed.

Apparatus for locating inoperative miniature bulbs in a string of bulbs


An imaging agent and a method of its use for imaging a necrosis in a tissue of a subject. The imaging method may be positron emission tomography (PET). In at least one embodiment the imaging agent comprises 2-deoxy-2-[18F]fluoroglucaric acid (18F-FGA), or a pharmaceutically-acceptable salt thereof. The imaging agent may be disposed in a pharmaceutically-acceptable excipient, carrier, diluent, or vehicle. The imaging agent may be contained within a kit. The disclosure includes in at least one embodiment a method of preparing a radiopharmaceutical such as 18F-FGA for use in imaging.

Myocardial infarction (MI) is a leading cause of death in the United States and in most developed nations throughout the world. MI can be an acute manifestation, due to a mismatch in oxygen demand and supply to the cardiac tissue, or chronic heart failure attributed mostly to the left ventricular dysfunction. Acute MI requires rapid diagnosis for effective and timely thrombolytic therapy, whereas chronic heart failure needs accurate assessment of myocardial viability and localization of dysfunctional region prior to revascularization. Non-invasive nuclear imaging procedures exhibit immense diagnostic value in evaluation of patients with MI. Depending on the parameter assessed, these procedures are categorized as perfusion imaging for assessing coronary blood flow (e.g., 99mTc-sesta-methoxyisobutylisonitrile (99mTc-sestamibi) and 201Tl—TlCl2) or metabolic imaging for quantifying cardiac metabolism (e.g., 18F-FDG (2-deoxy-2-[18F]fluoro-D-glucose) and 11C-acetate). A third nuclear technique is the infarct-avid scintigraphy. Infarct-avid scintigraphy is a relatively less utilized procedure, because an effective radiopharmaceutical is currently unavailable. Perfusion imaging tests rely on imaging agents which are taken up by living tissues, thus the areas of infarct or necrosis are indicated only indirectly. Perfusion imaging cannot differentiate between areas of low flow, ventricular thinning, and attenuation. Additionally, high liver uptake creates imaging artifacts which make image interpretation difficult. Finally, perfusion scans cannot discriminate between ischemic and necrotic regions because both show reduced perfusion.
In contrast to perfusion imaging agents, infarct-avid agents accumulate in the site of injury. Infarct-avid scintigraphy exhibits less background and enhanced signal-to-noise ratio, as there is no uptake by normal myocardium. The two currently usable infarct-avid agents are 99mTc-pyrophosphate (PyP) and 111In-antimyosin. They are called 'hot-spot' markers because of their tendency to accumulate in regions of infarcted myocardium. However, these agents have drawbacks. For example, regarding 111In-antimyosin, deficiencies include the relatively poor radionuclidic characteristics of 111In, delayed blood clearance, and pronounced hepatic uptake. On the other hand, PyP lacks specificity (64%), and exhibits poor sensitivity (40%) for subendocardial infarct detection. Moreover, PyP is not very useful in early diagnosis of acute MI as its uptake only becomes positive after 24-48 h of infarction. In addition to PyP and anti-myosin, a 99mTc-labeled analog of glucaric acid has been investigated for the acute localization of MI. Its avidity towards infarct is based on its binding to highly basic histones that are exposed in injured tissue. Single photon emission computed tomography (SPECT) with 99mTc-glucarate has been shown to be specific for the presence of myocardial necrosis, and has been able to address most drawbacks of PyP and 111In-antimyosin. However, a shortcoming of 99mTc-glucarate used in SPECT is that the 99mTc is only complexed with, not covalently linked to, the glucarate molecule. As a result over time the 99mTc may dissociate from glucarate and transchelate to other circulating ligands resulting in a less accurate diagnosis.
Positron emission tomography (PET) provides improved resolution and sensitivity of detection as compared to SPECT. Moreover, PET is less prone to image artifacts and attenuation. With recent introduction of 18F-labeled perfusion agents such as Flurpiridaz, myocardial perfusion imaging (MPI) with PET is likely to complement or supplant traditional SPECT/PET protocols for objective decision-making in the management of MI patients. However, there is currently no PET agent for specifically imaging myocardial infarcts.
Like acute MI, the pathology of brain stroke also involves the development of necrosis very early post-ictus. Brain stroke is the second most common cause of death worldwide, with considerable disability among survivors. Stroke-survivors exhibit considerable disability for a prolonged period, which totaled about 113 million disability-adjusted life years in 2013. Approximately 80% of brain strokes are from ischemic infarction due to thrombotic or embolic cerebrovascular occlusion, and the rest are categorized as hemorrhagic stroke. After transient ischemic attack (TIA) or minor stroke, the risk of further stroke reaches as high as 30% within the first month in some subgroups. Stroke consumes 2-4% of total health-care costs worldwide, but in developed countries the figure exceeds 4%. Current management of stroke patients is aimed at preventing the progression of at-risk cerebral tissue towards infarction by restoring blood supply to ischemic but viable tissue (a.k.a. penumbra). The timing of treatment with respect to the type and stage of evolution of stroke critically determines the treatment success. Neuroimaging based on diffusion-perfusion mismatch in magnetic resonance (MR) or computed tomography (CT) images is routinely employed for discerning non-viable and viable tissue and optimize treatment in brain stroke patients. However, diffusion-perfusion mismatch is not always a reliable indicator of salvageable tissue because some lesions show acute reversal, whereas others fail to transition into infarct. There also exists lack of consensus on thresholds employed for delineating diffusion and perfusion deficits in MR or CT images. Thus, infarct imaging would provide significant assistance in diagnosis and treatment planning of brain stroke.

THE BOARD OF REGENTS OF THE UNIVERSITY OF OKLAHOMA


A circuit with a sampling network may include a pair of capacitors, where each of the capacitors has a first node and a second node; a first pair of switches communicatively coupling corresponding differential input voltage signals to the first node of each of the capacitors; and a second pair of switches communicatively coupling the second node of each of the capacitors to a common mode voltage source. Corresponding differential output voltage signals at the second node of each of the capacitors may be communicatively coupled using a differential switch. The second pair of switches may be coupled in parallel with the differential switch. A clock signal of the differential switch may be de-asserted prior to de-asserting corresponding clock signals for each of the second pair of switches.

Sampling networks are widely used in many types of integrated circuits, such as analog-to-digital converters and filters, to convert a continuous time signal to a sampled-and-held signal. However, a key impairment in integrated circuits using sampling networks is distortion over a large input range. The signal distortion is largely due to signal dependent charge injection and kick-back on the driver of the sampling network.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such approaches with some aspects of the present method and apparatus set forth in the remainder of this disclosure with reference to the drawings.


A vehicle occupant restraint system, particularly for vehicle occupant side restraint, includes an inflatable gas bag which, in a restraint situation, is fully inflated and is arranged in a final, desired position to restrain a vehicle occupant, a gas generator and a means engaging the gas bag. The means pulls the gas bag in a restraint situation into the desired position and maintains it in this position when the vehicle occupant impacts the gas bag.

In a restraint situation an inflated gas bag needs to absorb the forces acting on it due to impact of the vehicle occupant and to direct them into the vehicle. For this purpose, a gas bag protecting in the case of a head-on collision is supported by the steering wheel hub or the dashboard, depending on whether a driver gas bag or a front passenger gas bag is involved. A cushion-shaped head gas bag as part of a side-acting restraint system is known from DE-U 92 11 423. In this arrangement a head gas bag is disposed under the cover of the roof frame from which it emerges in a collision situation. Eye-lugs at the outer surrounding edge of the gas bag surround a cable disposed along the B-pillar. On deployment of the gas bag the cable serves to guide the gas bag, as a result of which it expands downwards guided at the sides until it has assumed a defined final position. Prior to and during impact of the occupant on the gas bag provided in the case of the restraint system according to DE-U 92 11 423, the gas bag may move along this cable guide and partly change its position, which is undesirable.
Furthermore, cushion-shaped side gas bags are known which in a restraint situation are supported by the side window of the vehicle. If, however, the window shatters in the case of a side collision, the gas bag is lacking support to a major extent so that its restraint effect is at least severely restricted.


A controller for a drive train of a motor vehicle having an engine and an automatic transmission, includes an engine controller through which variables that influence the torque of the engine are controlled, a transmission controller through which shift processes of the automatic transmission are controlled, and an interface which connects the engine controller and the transmission controller to one another and through which data are transmitted to give the vehicle good handling. The interface is used to transmit a status signal which signals to the transmission controller that catalytic converter regeneration is taking place, and through which a shift process in the transmission is changed in the transmission controller.

Field of the Invention
The invention relates to a controller for the drive train of a motor vehicle (a drive train controller) having an engine and an automatic transmission.
As disclosed in German Patent DE 29 34 477 C3, conventional transmission and engine controllers vary the ignition angle to reduce engine torque with the aim of improving the ease of gear shifting and of reducing the stress on the transmission. In the case of engine and transmission controllers that are to be developed as new items, one prime necessity is to reduce pollution emissions. In order to do that, local improvements are being aimed for, that is to say an improvement in the engine system on one hand and in the transmission system on the other hand. However, since the two systems influence one another, such improvements result in limitations to the operation of the motor vehicle.
In the case of a known motor vehicle drive train according to U.S. Pat. No. 5,311,794, the cylinder of a lean-burn engine has a plurality of inlet valves, one of which (a swirl control valve) is open when the engine load is relatively high and is closed when the load is low. The air-fuel mixture ratio is higher when that valve is closed than when it is open. The fact that the valve is switched on or off for changing its position is a signal to the transmission controller, which suppresses any transmission shift process then and for a time interval after the change. Special engine operating conditions are not taken into account in the process.
A known motor vehicle according to German Published, Non-Prosecuted patent application DE 43 32 456 A1 has an engine with an exhaust catalytic converter, having an exhaust purity level that reduces with age. The automatic transmission in that motor vehicle has at least one economy shift program and one sport shift program, and it is provided with a device through which the transmission is automatically switched to the sport program at the start of the engine warming-up phase, in order to heat the catalytic converter more quickly. The transmission is automatically switched back to the economy program once the sport program has been switched on for a time that becomes longer as the total operating duration or total distance driven becomes greater.
A motor vehicle drive train having a Diesel engine and a transmission has a fuel controller which is dependent on the performance required by the driver. A plurality of families of characteristics contain empirically derived data relating to exhaust components and fuel consumption, according to Published European Patent Application EP 0 474 401 A2. The transmission controller uses the vehicle speed and the performance requirement together with an evaluation of the families of characteristics to determine which of those gear ratios that may be used for a permissible engine operating range is the "optimum". The optimum gear ratio is indicated. The optimization is carried out on the basis of low fuel consumption and the exhaust characteristics, and those criteria can be weighted in the process. That results in adaptive correction of the data in the fields of characteristics for the most useful engine operating range.

Controller for the drive train of a motor vehicle


Various embodiments are directed to systems and methods for work queue thread balancing. A global thread pool manager may be configured to receive a request to add a work item to a constituent work queue. The constituent work queue may be described by a work queue thread property. The global thread pool manager may add the work item to the constituent work queue and match the work item to a global thread selected from a global thread pool. The global thread may be configured according to the work queue thread property to generate a configured global thread. The configured global thread may execute the work item.

Work queues are utilized by many modern operating systems to manage asynchronous processing tasks. When an application or other system component discovers a processing task, e.g., a work item, that does not need to be completed immediately, it places the work item on a work queue. The work queue typically has one or more dedicated threads. A thread is a unit of software that can be executed by a processor or processor core. A different component manages the execution of the work queue threads, as well as other threads. When executed, the work queue threads pull items from the work queue and execute them, often according to a first in-first out (FIFO) arrangement. In this way, work items that are not time sensitive or that benefit from "batch" processing can be queued and performed when the computer has available processing resources. Examples of work items that are often queued include interrupt processing, input/output (I/O) requests, garbage collection, etc.
Many systems support both platform work queues and user work queues. Platform work queues are typically managed by the operating system and are made available to a wide range of applications and/or other system components. User work queues are created by applications and are used by a limited set of system components. User work queues are often used to avoid race and deadlock conditions that can occur with platform work queues or existing user work queues. For example, when a work item (A) requires a result of another work item (B) to complete its processing task, the work item (A) cannot be completed until after the work item (B) is completed. If the work item (A) begins to execute before the work item (B) is completed, the thread executing the work item (A) will go into a wait state. If there are not sufficient dedicated threads to process the work item (B), then the thread executing the work item (A) will remain it its wait state indefinitely, which is referred to as a deadlock condition. In another example, a work item (X) may be coded to assume that another work item (Y) has already executed and made particular changes to system data. If the work item (X) is executed before the work item (Y), system data may not be in the state expected by work item (X), resulting in a race condition.
User work queues give software developers additional control to prevent race and deadlock conditions. At the same time, however, each work queue consumes system resources. For example, each active thread for a work queue utilizes physical memory space that is either filled or reserved for the thread. As more and more work queues are used, more resources are consumed. Thus, while individual applications may be optimized overall system performance suffers.


A method to prioritize sidelink logical channel (SL LCH) during destination UE selection for sidelink Logical Channel Prioritization (LCP) procedure in NR sidelink communication is proposed to avoid resource starvation. A TX UE prioritizes an RX UE having at least one SL LCH that has not satisfied a required minimum bit rate during destination UE selection when allocating SL resource to a new MAC PDU for SL transmission. The TX UE maintains a value Bj for each SL LCH j, where Bj>0 indicates that the logical channel has not met the requirement of prioritized bit rate. If at least one destination UE has SL LCH with data available for transmission and with Bj>0, then the selected destination UE is the one has the highest-priority SL LCH with data available for transmission and with Bj>0.

Third generation partnership project (3GPP) and Long-Term Evolution (LTE) mobile telecommunication systems provide high data rate, lower latency and improved system performances. In 3GPP LTE networks, an evolved universal terrestrial radio access network (E-UTRAN) includes a plurality of base stations, e.g., evolved Node-Bs (eNBs) communicating with a plurality of mobile stations referred as user equipment (UEs). Orthogonal Frequency Division Multiple Access (OFDMA) has been selected for LTE downlink (DL) radio access scheme due to its robustness to multipath fading, higher spectral efficiency, and bandwidth scalability. Multiple access in the downlink is achieved by assigning different sub-bands (i.e., groups of subcarriers, denoted as resource blocks (RBs)) of the system bandwidth to individual users based on their existing channel condition.
To meet the demand of this exponential increase in communications, additional spectrum (i.e. radio frequency spectrum) is needed. The amount of licensed spectrum is limited. Therefore, communications providers need to look to unlicensed spectrum to meet the exponential increase in communication demand. An established communication protocol such as 4G LTE and 5G New Radio (NR) can be used over the licensed spectrum to provide a first communication link, and LTE/NR can also be used over the unlicensed spectrum to provide a second communication link. In New Radio-Unlicensed (NR-U), any downlink and uplink access have to follow the listen-before-talk (LBT) channel access procedure, as unlicensed frequencies are also used by other networks such as WiFi.
For in-coverage UEs, a base station can schedule the data traffic over Uu link. For out-of-coverage UEs, UE can schedule the data traffic over PC5 (or sidelink). As compared to WiFi and NR unlicensed spectrum operation, a PC5 link (or sidelink) based mobile device potentially possesses the following features: 1) deployment by both operator can user; 2) operation in both unlicensed spectrum and licensed spectrum; 3) similar protocol stacks complexity to WiFi; 4) better multiplexing efficiency than WiFi; 5) better mobility support than WiFi, e.g., service continuity; 6) larger maximal TX power than WiFi for larger coverage: 7) support multi-hop relay.
There are potential problems in the current LTE vehicle-to-everything (V2X) design utilizing sidelink transmission. First, there may be resource starvation among destination UEs. In LTE V2X, a transmitter UE always selects the destination UE with the highest-priority sidelink logical channel (SL LCH) with data available for transmission among multiple receiver UEs. However, if such LTE V2X design for destination UE selection is directly applied, there is a problem of resource starvation among destination UEs. That is, a destination UE with a highest-priority SL LCH can always occupy the whole MAC PDU (SL grant) of the transmitter UE regardless of how much SL data the transmitter UE had sent for the high-priority SL LCH in previous MAC PDUs. This means other destination UEs without the highest-priority SL LCH cannot be scheduled by the transmitter UE with any SL transmission (i.e. resource starvation) until the transmitter UE has transmitted all the data of the highest-priority SL LCH. Second, diverse communication range is not yet supported. In NR V2X, diverse V2X applications are supported. Based on the applications different minimum communication ranges are supported. If UE is configured with a huge SL grant, due to power limitation in sidelink, UE may not able to send the large SL grant with a wide coverage. In other words, for some V2X applications requiring a large communication range (i.e. wide coverage), the applicable SL grant cannot be too large, i.e. a limit is needed to ensure the minimum communication range is satisfied. Currently, the restriction is not yet considered in the procedure for SL resource allocation. Third, there are issues of Hybrid Automatic Repeat reQuest (HARQ) collision. In mixed mode operation, both NW and UE can select SL resource for transmission. Each new SL grant transmission is associated with a HARQ process for new transmission and retransmission. Since there is no coordination between NW and UE scheduler, it is possible that NW and UE perform SL transmission for the same destination UE and the same HARQ process ID. It is not clear how to handle the case of HARQ collision.
A solution is sought.

Enhancement of logical channel prioritization for sidelink transmission


Disclosed is an internal voltage generator, which includes a detecting means for detecting a level of an internal voltage, an oscillator for generating a driving pulse signal in response to an output signal of the detecting means, a first driving unit for outputting a first pulse signal after receiving the driving pulse signal, a second driving unit for outputting a second pulse signal after receiving the driving pulse signal, and a pumping unit for changing a potential level of the internal voltage after selectively receiving one of the first pulse signal and the second pulse signal.

1. Field of the Invention
The present invention relates to an internal voltage generator, and more particularly to an internal voltage generator capable of outputting a back-bias voltage used as a substrate bias voltage of a semiconductor device.
2. Description of the Prior Art
Generally, an internal voltage generator is a circuit for generating an internal voltage used in a semiconductor device. The internal voltage generator includes a high voltage generator for generating an internal voltage larger than a supply voltage, a back-bias voltage generator for generating an internal voltage smaller than a ground voltage, a reference voltage generator for generating a predetermined reference voltage, etc.
For example, in a case of a memory device, which is a kind of semiconductor device, a high voltage generator is used for activating a word line. Further, a back-bias voltage generated by a back-bias voltage generator is applied to an N-well including a PMOS transistor, thereby adjusting the threshold voltage of the PMOS transistor.
FIG. 1 is a block diagram of a general internal voltage generator (in particular, a back-bias voltage generator).
As shown in FIG. 1, the back-bias voltage generator for generating a back-bias voltage VBB (internal voltage) includes a detection circuit 101 for detecting a back-bias voltage, a driving circuit 102 for outputting a predetermined pulse signal in response to the output signal of the detection circuit 101, and a pumping circuit 103 for lowering the back-bias voltage by a pumping operation when the pulse signal is applied from the driving circuit 102.
In the operation of the back-bias voltage generator, the pumping circuit 103 continues to perform the pumping operation until the back-bias voltage outputted from the pumping circuit 103 reaches a target level. Accordingly, after the back-bias voltage has reached the target level, the pumping circuit 103 stops the pumping operation and maintains the back-bias voltage at that time.
However, in the prior art, when a supply voltage VDD operating the driving circuit 102 of the back-bias voltage generator is unstable, the pulse signal applied to the pumping circuit 103 is also unstable. Therefore, it is difficult to generate a stable back-bias voltage.
In particular, since the supply voltage VDD of a semiconductor device has been recently lowered, the instability of the supply voltage may immediately cause the instability of an internal voltage.

Internal voltage generator for semiconductor device


A communication apparatus includes an acquisition unit (551) acquiring information from a base station apparatus, a determination unit (552) determining whether a connected base station apparatus is a non-ground station or a ground station based on the acquired information, and a communication controller (553) executing communication control for the non-ground station when it is determined that the connected base station apparatus is the non-ground station.

Mobile communication using radio access technologies such as cellular communication technologies is known. In such radio access technologies, along with movement of a communication apparatus such as a cellular phone, switching of a radio base station apparatus (hereinafter, referred to as a base station apparatus or a base station) to which the communication apparatus is connected is performed. For the base station, apart from a ground station installed on the ground, for example, a non-ground station up in the air such as an artificial satellite is being studied, for example. For the communication apparatus, apart from radio communication connected to the base station and via the base station, radio communication connected to the non-ground station and via the non-ground station is being studied.

Communication apparatus and method of communication


A protective screen for use with a pitching machine. The pitching machine for pitching balls. The protective screen having a passageway defined there-through for permitting a ball to be pitched by the pitching machine there-through. The protective screen having a door configured for opening and closing in concert with the pitching of balls so as to open to permit a ball to be pitched there-through but automatically closed right there-behind to protect the operator of the pitching machine from injury due to a batted ball.

The training of athletes, namely baseball and softball players, to properly hit baseballs/softballs is frequently done. Typically, a batter will spend time within a "batting cage" receiving balls pitched by a commercial pitching machine. Alternatively, portable pitching machines are known in the prior art and are utilized by coaches to pitch balls to batters.
Any time one is playing a sport such as baseball or softball, there is a chance that a person in the field will be struck by a batted ball. Within games it is not infrequent for a pitcher to be stricken by a batted ball, often causing injury to the pitcher. This same problem arises when coaches are pitching balls to batters during batting practice, whether they are pitching using a manually fed machine, other pitching machines which requires manual operation, or throwing the balls by hand.
Various different types of pitching screens are well known in the prior art for protecting and/or shielding the pitcher of the ball. Typically such devices have an upward extending portion for protecting the pitcher's body with a cut-out that allows the ball to be thrown over the top portion of the screen. A general example of such a screen can be seen in U.S. Pat. No. 6,955,615.
Screening set up with regard to pitching machines typically have a hole cut within the screening material so as to let the ball be projected through the hole and to the batter. An example of such a hole is shown in U.S. Pat. No. 5,195,744. Theoretically, a ball could be hit by a batter back through the hole (13) and strike the pitching machine and/or pitching machine operator.
What is needed is a portable protection screen for use with a pitching machine that protects an operator of the machine standing behind the screen but allows for complete and full operation of the pitching machine.

Portable protection screen for pitching machine