Pozzolan compositions incorporate glassy, amorphous particulates derived from byproducts of processes in which substantial energy was invested in generating those byproducts, at least one of which comprises amorphous calcium silicate slag generated as a byproduct of phosphorous production. The calcium silicate particulate is blended with one or more additional pozzolans, preferably one or more particulates of a material selected from the group consisting of fused silica of the type generated as a byproduct of making refractory grade fused silica and cullet glass of the type rejected from glass making processes. Pozzolanic cements incorporating up to about 50% by weight of such pozzolan compositions are also disclosed.

Pozzolans of various particular kinds are known in the prior art as being useful as performance-enhancing additives for cement, mortar, grout, stucco and concrete. Unless otherwise indicated, the term "cement" is used herein to refer collectively to cement, mortar, grout and stucco and "concrete" is used to refer to a mixture of an aggregate with a cement. Though pozzolans by themselves are generally of little, if any, use as a cement, the addition of pozzolans to either common or hydraulic portland cement enhances both the initial and long term physical properties of the cement. Pozzolans continue to participate in bond-forming reactions react in cement for many years, further strengthening the concrete and making it harder and more durable as time passes. Pozzolans also serve to densify and reduce water permeability of cured concrete thereby making the cement or concrete more resistant to deterioration and swelling caused by exposure to various conditions.
A pozzolan is a siliceous, or siliceous and aluminous, substance which will react at ordinary temperatures with calcium hydroxide formed during the hydration of cement to create additional cementitious material in the form of dicalcium and tricalcium silicate and calcium silico-aluminate hydrates. The American Society for the Testing and Materials Standard ASTM C-618, entitled "Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use As a Mineral Admixture in Concrete" defines various classes of pozzolans. For example, a Class "N" Pozzolan are defined therein as "raw or calcined natural pozzolans that comply with the applicable requirements for the class as given herein, such as some diatomaceous earths; opaline cherts and shales; tuffs and volcanic ashes or pumices, calcined or uncalcined: and various materials requiring calcination to induce satisfactory properties, such as some clays and shales." Class F Fly Ash is defined as "fly ash normally produced from burning anthracite or bituminous coal that meets the applicable requirements for this class as given herein. This class of fly ash has pozzolanic properties." Class C Fly Ash is defined as "fly ash normally produced from lignite or sub-bituminous coal that meets the applicable requirements for this class as given herein treated this class of fly ash, in addition to having pozzolanic properties, also has some cementitious properties."
Portland cement is a fine powder produced by grinding portland cement clinker. The major raw material for making portland cement clinker is a mixture of calcium carbonate (CaCO3), usually in the form of crushed limestone, and materials containing clay as a source of alumino-silicate. Normally, an impure limestone which contains clay or SiO2 is used. Some of the secondary raw materials which can be incorporated in the mixture for making clinker are: clay, shale, sand, iron ore, bauxite, fly ash and slag. The raw mixture is heated in a cement kiln, a slowly rotating and sloped cylinder, with temperatures increasing over the length of the cylinder up to a peak temperature of about 1400-1450° C. A complex succession of chemical reactions take place as the temperature rises. The resulting clinker is a hydraulic material which consists of at least two-thirds by mass of dicalcium and tricalcium silicates (3CaO.SiO2 and 2CaO.SiO2) with the balance consisting mainly of aluminum-containing, and iron-containing, clinker phases and other compounds. The aluminum oxide and iron oxide are present as a flux and contribute little to concrete strength.
Due to the high temperature needed, the production of portland cement clinker requires large amounts of energy. The enthalpy of formation of clinker from calcium carbonate and clay minerals is about 7.1 MBTU per ton. However, because of heat loss inherent in actual production processes, the total heat input required can be much higher. The high energy requirements and the liberation of significant amounts of carbon dioxide in the course of generating the energy necessary to satisfy production requirements make cement production a significant source of carbon dioxide (CO2) emissions. CO2 release to the atmosphere on the order of 1.1 tons per ton of cement is not atypical. It has been estimated that portland cement production may account for as much as 5% of CO2 emissions worldwide.
The incorporation of certain types of pozzolans in cement is known in the art. For example, standard ASTM C-150 classifies portland cements as one of five basic types. The first three types allow for specific pozzolan additions in accordance with overall chemical and physical performance criteria. For example, "Type I" is considered common, or general purpose, portland cement. It is typically used for general construction and is especially useful for making precast and precast-pre-stressed concrete members that are not to be used in contact with soils or ground water. Using cement industry notation, a typical composition of a Type I portland cement is: 55% (C3S), 19% (C2S), 10% (C3A), 7% (C4AF), 2.8% MgO, 2.9% (SO3), 1% free (CaO). Type II cement is intended to have moderate sulfate resistance with or without moderate heat of hydration and is suitable for general use in contact with ground water exposed to moderate sulfide attack. A typical composition of a Type II portland cement would be 51% (C3S), 24% (C2S), 6% (C3A), 11% (C4AF), 2.9% MgO, 2.5% (SO3), 1% free (CaO) with C3A not exceeding shall not exceed 8% and (C3A+C3S) not exceeding 58%. Type III portland cement exhibits relatively high early strength. A typical composition thereof is: 57% (C3S), 19% (C2S), 10% (C3A), 7% (C4AF), 3.0% MgO, 3.1% (SO3), 1.3% free (CaO). A Type IV portland cement is slow curing and is generally known for its low heat of hydration. A typical composition of Type IV is: 28% (C3S), 49% (C2S), 4% (C3A), 12% (C4AF), 1.8% MgO, 1.9% (SO3), 0.8% free (CaO) with C3A not in excess of 7% and C3S not in excess of 35%. Type V portland cements are typically used where sulfate resistance is important, such as applications with exposure to high alkali soil and/or sulfate groundwater. A typical Type V composition is: 38% (C3S), 43% (C2S), 4% (C3A), 9% (C4AF), 1.9% MgO, 1.8% (SO3), 0.8% free (CaO) with C3A>2% and (2C3A+C4AF) not in excess of 20%.
ASTM C-1157 deals with hydraulic cements. That standard does not impose restrictions the chemical composition of the cement itself or its additives. Rather, it establishes standards of physical performance indicating the suitability of a cement for particular applications. For example:
Type GU—General Purpose cement
Type HE—High Early-Strength
Type MS—Moderate Sulfate Resistance
Type HS—High Sulfate Resistance.
Type MH—Moderate Heat of Hydration.
Type LH—Low Heat of Hydration.
ASTM Standard C-595 sets forth specifications for five classes of blended hydraulic cements for general and special application, using slags, pozzolans, or both, blended with portland cement.
Type IS—Portland/Blast Furnace Slag Cement—includes 25% to 70% blast furnace slag.
Type IP & P—Portland/Pozzolan cement—includes 15 to 40% pozzolan blended with either portland cement or Type IS cement.
Type I (PM)—Pozzolan modified portland cement—includes <15% Pozzolan blended with either portland cement or Type IS cement.
Type S—Slag cement>70% blast furnace slag ASTM C 989 blended with either portland cement or hydrated lime.
Types IA, IIA, and IIIA are the same as I, II, and III with the addition of air-entraining additives. Similarly, suffix MS is used to indicate moderate sulfide resistance, and suffix MH us to indicate moderate heat of hydration. Other suffixes are used to indicate subtypes exhibiting other particular properties.
ASTM Standards ASTM C-150, ASTM C-465, ASTM C-595, ASTM C-618, ASTM C-989 and ASTM C-1157 are expressly incorporated herein in their entireties to form part of the present disclosure.
U.S. Pat. No. 6,776,838 describes a white pozzolan, and a cement incorporating white pozzolan derived from byproducts of manufacturing vitreous low alkali, low iron, glass fibers such as those used for example and fiberglass thermal insulation. Bundles all of entangled strands of waste glass fibers are adjusted for moisture content, shredded, ground, and classified to control maximum particle size, particle distribution and aspect ratio before being blended with portland cement.
However, the prior art does not appear to disclose, suggest or otherwise motivate a person of ordinary skill in the art to provide a blended pozzolan composition comprised of calcium silicate and at least one waste byproduct of a glass material or glass product production processing process. In particular, the prior art lacks any teaching or motivation to provide a pozzolan composition which comprises calcium silicate, itself a waste byproduct of the production of elemental phosphorous, with cullet glass recovered from a glass-making facility and/or fused silica recovered from the process of making high purity refractory grade-fused silica. The prior art also lacks pozzolanic cements in which a pozzolan composition of the aforementioned makeup is admixed with a portland cement.

Energy conserving pozzolan compositions and cements incorporating same


Embodiments relate to enrichment of a data warehouse utilizing a business compendium. Embodiments may employ a process comprising data standardization and cleansing, de-duplication of entries, and matching and enrichment, followed by manual review of an enriched record by a user. During standardization, data may be transformed into consistent content, placing correct data elements into appropriate fields, removing invalid characters, and/or standardizing names and addresses. Duplicate records are then detected and marked. During matching and enrichment, the existence of an entity (such as a supplier), may be verified by progressive matching against the business compendium. Enrichment may provide additional information regarding the entity (e.g. related to risk, diversity, and bankruptcy). The enriched record is available for manual review, allowing the user to change duplicates, matches, and parent/child linkages. Feedback from the user review may enhance accuracy of subsequent enrichment by self-learning aspects, reducing over time a need for manual review.

Embodiments of the present invention relate to data warehouses, and in particular, to systems and methods employing data enrichment using a business compendium.
Unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Effective resource planning for the enterprise may depend upon the accuracy and detail of underlying records. For example, where supplier identities are obscured due to poor data quality and/or lack of content in a data warehouse, the depth of understanding of a supply base may be hindered. This lack of visibility may interfere with rightful insight on supplier information, and aggregated spend towards those suppliers.
Accordingly, the present disclosure addresses these and other issues with systems and methods employing data enrichment using a business compendium.

Data enrichment using business compendium


A lens barrel comprises a vibration detecting device for detecting a vibration, a correcting optical device for correcting the vibration on the basis of an output of the vibration detecting device, and a diaphragm unit having a variable aperture diameter, and the vibration detecting device is disposed in a plane which is approximately flush with a driving part for the diaphragm unit and perpendicular to an optical axis, or the vibration detecting device is formed on or integrally with a lens barrel portion which holds an optical member other than the correcting optical device.

1. Field of the Invention
The present invention relates to a lens barrel which is arranged to restrain an image shake by detecting a vibration occurring in an optical apparatus such as a camera and moving correcting optical means in a direction perpendicular to the optical axis of the lens barrel by using the detected vibration as information for preventing an image shake, as well as to an optical apparatus having such lens barrel.
2. Description of Related Art
All the operations of current cameras that are important for photography, such as exposure decision and focusing, are automated, and even persons who are unfamiliar with camera operation rarely fail in photography. In addition, a system for correcting a vibration applied to a camera and preventing an image shake has recently been developed, and is proposed in, for example, Japanese Laid-Open Patent Application No. Hei 3-188430.
A camera system for preventing an image shake will be briefly described below.
Vibrations which are applied to cameras during photography normally have a frequency of 1 Hz to 12 Hz, and a basic concept for enabling a user to take a photograph free of an image shake with a camera even if such a vibration is applied thereto at the time of shutter release is to detect the vibration of the camera and displace the aforesaid correcting optical means according to the detected value.
Accordingly, in order to enable the user to take a photograph free of an image shake even if a vibration is applied to the camera, first, it is necessary to accurately detect the vibration of the camera, and secondly, it is necessary to correct a change based on the vibration in the photographing optical axis of the camera.
Theoretically, the detection of such vibration can be realized by incorporating vibration detecting means for detecting angular acceleration, angular speed, angular displacement and the like in a camera or a lens. An image shake can be restrained by driving and displacing correcting optical means for decentering the photographing optical axis on the basis of the detected information.
An image stabilizing system using such vibration Ad detecting means will be briefly described with reference to FIG. 8.
FIG. 8 schematically shows an example of a system for restraining an image shake derived from a vertical vibration p and a horizontal vibration y of a camera. The shown example includes a lens barrel 1, vibration detecting means 2p for detecting the vertical vibration p, and vibration detecting means 2y for detecting the horizontal vibration y. Reference numerals 3p and 3y denote the vibration detecting direction of the vibration detecting means 2p and the vibration detecting direction of the vibration detecting means 2y, respectively. The shown example also includes correcting optical means 4 which has coils 5p and 5y for giving thrust to the correcting optical means 4, and detecting elements 6p and 6y for detecting the position of the correcting optical means 4. The correcting optical means 4 is provided with a position control loop, and is driven by using the outputs of the vibration detecting means 2p and 2y as target values, to ensure stabilization of an image in an image plane 7.
As described above, as the number of functions of the apparatus itself is increased, more various elements such as vibration detecting means and driving means for driving the correcting optical means need to be incorporated into the apparatus. Accordingly, it is necessary to design the lens barrel so that a dead space therein can be efficiently used.
In the conventional lens barrel, since the vibration detecting means are provided in the vicinity of the mount of the lens barrel, the vibration detecting means need to be incorporated in a shield component which completely cover them, in order to reduce the disturbance of the vibration detecting means, such as the noise of a mirror-up operation of a camera.
However, if the vibration detecting means are disposed in the vicinity of the mount, as in the conventional example, an increase in the entire optical length of an optical system is involved.
In addition, the vibration detecting means need to have a shield component for preventing the disturbance, and needs a larger number of components and has the problem of inferior easiness of assembly.

Lens barrel and optical apparatus having the same


A computer system is provided. The computer system includes a memory and a processor coupled to the memory. The processor is configured to receive a first message from an identity provider, the first message including an arbitrary identifier generated by the identity provider, the arbitrary identifier being incompatible with a dependent process that is reliant upon the identity provider; encode, in response to reception of the first message, the arbitrary identifier into an encoded identifier that is compatible with the dependent process; and transmit a second message including the encoded identifier to the dependent process.

Identification of system elements is a fundamental computing concern. As such, practitioners skilled in the computing arts have developed a variety of conventions to identify various system elements. Identifiers generated using these conventions include universally unique identifiers (UUIDs), global unique identifiers (GUIDs), object identifiers (OIDs), and security identifiers (SIDS) to name only a few examples. Widely adopted identifiers, such as the aforementioned examples, are automatically generated by various identity providers and processed by a vast base of existing code.

Adaptive identification systems and methods


Techniques for transmitting data from virtual antennas instead of physical antennas are described. Each virtual antenna may be mapped to some or all physical antennas by a different mapping. The performance of different sets of at least one virtual antenna is evaluated based on one or more metrics such as signal quality, throughput, overall rate, and so on. The virtual antenna set with the best performance is selected for use. If the virtual antenna selection is performed by the receiver, then channel state information for the selected virtual antenna set may be sent to the transmitter. The channel state information may convey the selected virtual antenna(s), the signal quality or rate(s) for the selected virtual antenna(s), one or more preceding matrices used to form the selected virtual antenna(s), and so on. The transmitter and/or receiver use the selected virtual antenna(s) for data transmission.

I. Field
The present disclosure relates generally to communication, and more specifically to techniques for transmitting data in a wireless communication system.
II. Background
In a wireless communication system, a transmitter (e.g., a base station or a terminal) may utilize multiple (T) transmit antennas for data transmission to a receiver equipped with multiple (R) receive antennas. The multiple transmit and receive antennas may be used to increase throughput and/or improve reliability. For example, the transmitter may transmit T symbols simultaneously from the T transmit antennas to improve throughput. Alternatively, the transmitter may transmit the same symbol redundantly from all T transmit antennas to improve reception by the receiver.
The transmission from each transmit antenna causes interference to the transmissions from the other transmit antennas. In some instances, improved performance may be achieved by transmitting fewer than T symbols simultaneously from the T transmit antennas. This may be achieved by selecting a subset of the T transmit antennas and transmitting fewer than T symbols from the selected subset of transmit antenna(s). The transmit antenna(s) that are not used for transmission do not cause interference to the transmit antenna(s) that are used for transmission. Hence, improved performance may be achieved for the selected subset of transmit antenna(s).
Each transmit antenna is typically associated with certain peak transmit power that may be used for that antenna. The peak transmit power may be determined by a power amplifier used for the transmit antenna, regulatory constraints, and/or other factors. For each transmit antenna that is not used for transmission, the transmit power for that antenna is essentially wasted.
There is therefore a need in the art for techniques to more effectively utilize the transmit power available for the transmit antennas.


An apparatus for detecting a null symbol of an input signal includes: a first circuit for processing the input signal to obtain a first output signal, the first output signal being used to track the influence of a channel phenomenon; a second circuit for processing the input signal to obtain a second output signal, the second output signal being used to track the null symbol in the input signal; and a determining circuit coupled to the first circuit and the second circuit and determining the null symbol of the input signal according to the first output signal and the second output signal. A method for detecting a null symbol of an input signal is also disclosed.

1. Field of the Invention
The present invention relates to an apparatus and method for detecting a null symbol. More particularly, the present invention relates to an apparatus and method for detecting a null symbol in an input signal of, for example, a digital audio broadcasting system.
2. Description of the Related Art
Referring to FIG. 1, a digital audio broadcasting (DAB) signal includes a plurality of frames. As shown in FIG. 2, each of the frames includes two types of reference symbols and a plurality of data symbols. The first type of reference symbol is a null symbol that is used in frame synchronization, has a strength of zero, and is typically positioned at a frontmost end of a frame. The second type of reference symbol is a phase reference symbol.
Referring to Table 1 below, a DAB system supports four different transmission modes. A length of the null symbol in each frame is different in these modes.
TABLE 1Mode 1Mode 2Mode 3Mode 4Null symbol Length1.297 ms324 μs168 μs648 μs
A receiving end in the DAB system must determine a starting point of all the frames in a received signal (that is, a starting point of a null symbol), and must further determine which of the four modes the signal is in.
U.S. Pat. No. 7,006,577 discloses an apparatus for detecting a transmission mode using null symbol length which is determined by detecting the starting and end points of a null symbol. This conventional apparatus includes a first window buffer and a second window buffer that store square values of samples for the first and the second search periods, respectively. However, since the apparatus of U.S. Pat. No. 7,006,577 requires two window buffers, the apparatus occupies significant system resources and cannot perform real-time processing.
U.S. Pat. No. 6,731,702 and U.S. Pat. No. 7,065,171 disclose related conventional methods. However, these two methods are unable to determine the transmission mode of signals, and a receiving end must know in advance the transmission mode of the signals, and the lengths of a null symbol and a frame in order to determine a starting point of a null symbol. Therefore, these methods are impractical in actual use.
Another important consideration in DAB systems is that related to fading of a received signal. In particular, if a receiving end in a DAB system is installed on a vehicle, a fading phenomenon may occur in a channel between a transmission end and the receiving end, particularly when the vehicle is traveling at a high speed. Therefore, when detecting a null symbol, this phenomenon must be taken into consideration so as to prevent the erroneous detection of null symbols.

Apparatus and method for detecting null symbols


A traffic informational system provides information to traffic moving along a road and may include a plurality of traffic information devices mountable to the road, each having an integral power producing source, at least a first set of illumination sources, and a wireless communications subsystem. The traffic informational system may further include at least a first external control device comprising at least one antenna and a transmitter communication wirelessly with the traffic information devices and/or with one another. The traffic information device may communicate with one another, and may include sensor for sensing ambient conditions. The system employs various approaches to reducing power consumption and improving communications, and is suitable for a wide range of applications, including use in remote environments.

1. Field of the Invention
This disclosure relates to traffic safety and communication methods, systems and/or devices, specifically for advanced warning and notification to vehicular and pedestrian traffic.
2. Description of the Related Art
Prior approaches have employed a set of visual indicators mounted to a road to provide visual indications to approaching traffic.
For example, U.S. Pat. No. 4,570,207 teaches locating the visual indicators in apertures or channels formed in a road, such that a top surface of each of the visual indicators is flush with the top surface of the road. The visual indicators are formed with an exterior that wears away, in a similar fashion to the top surface of the road, to maintain the top surface of the visual indicators flush with the road.
Also for example, U.S. Pat. Nos. 6,384,742 and 6,597,293 teaches the placement of visual indicators at crosswalks and/or intersections. The indicators may be affixed or embedded in the roadway. The visual indicators may be activated by an activation device, for example, via a loop detector embedded in the road or other device that detects the approach of a vehicle. Alternatively, or additionally, the visual indicators may be activated by an activation device, for example, a manual switch such as a pedestrian operated push button, sensor, and/or conventional traffic timing mechanism. Power may be supplied via a utility grid, or from a photovoltaic array positioned on a pole adjacent the roadway.
Previous approaches employing road mounted visual indicators are inefficient, expensive and/or cumbersome. For example, providing power and/or communications typically requires the laying of wires or cable along or underneath the road, a sidewalk, and/or an area adjacent the road. Such often requires trenching across an entire length or width of the road. For example, prior approaches typically require digging up large portions of the road, sidewalk and/or adjacent areas, via trenching or saw-cutting. In addition to trenching of the road to create locations for mounting the visual indicators, previous approaches require additional trenching in order to provide power and/or communications. Thus, additional trenching is required to provide power to the visual indicators from an existing power producing source, typically located along a curb or street. Additionally trenching may also be required to provide power to the activation device (e.g., loop sensor, other sensor, manually activated button, etc.). Further, additional trenching may be required to provide communications between the activation device and the road mounted visual indicators.
Such prior approaches typically also require the installation of a costly transformer box to transform power from a higher voltage (e.g., 110V or 240V provided by a utility grid) to a smaller voltage amount (e.g., 12 volts) for use by the road mounted visual, or by the activation devices.
Despite market demand, no known previous approach has successfully addressed these issues. Know approaches have also failed to adequately address minimizing power consumption while maximizing efficiency and sensory output. Thus, prior approaches miss a very high percentage, such as 90%, of potential implementations for in-surface devices, due to concerns over cost and/or inconvenience.

Methods, systems and devices related to road mounted indicators for providing visual indications to approaching traffic


A support bracket is provided for fastening to a concrete molding form. The bracket has a first and second distal end connected by a middle portion. The distal ends are generally in a first plane and the middle portion extends from a side of each distal end at an obtuse angle relative to that plane. The distal ends are releasably fastened to the form during use of the bracket, with the middle portion extending to be embedded in the concrete. After removal of the form, one or both of the distal ends are bent away from the concrete during use, with pipes being inserted through the openings in the distal ends. The support bracket may incorporate an internally-threaded and generally tubular structure attached to the middle portion of the support bracket, with one end of the tubular structure embedded in the concrete during use and the other end exposed at the plane of the concrete surface for useful access to the internal threads.

It is often necessary to hang various pipes from ceilings of buildings. If the ceilings are made of poured concrete, then the supporting brackets can be nailed to the concrete. But because concrete is so hard, the nails must be driven by very high impact tools. Because concrete is brittle, the driving of such nails can crack the concrete. Moreover, the high-power nail guns must be held overhead to fasten the hangers to the ceiling. There is thus a need for a pipe support that does not require lifting heavy tools overhead, and which is easier to use, and which does not crack the concrete.
Alternatively, threaded fasteners may be embedded in the concrete either by drilling holes in the concrete after it has cured and inserting the fasteners into the holes, or by attaching the fasteners to the concrete form before pouring the concrete, thus later embedding the fasteners in the concrete. The first of these alternatives has the disadvantage of once again requiring heavy tools to be lifted overhead to drill holes, while both alternatives require multiple fasteners, brackets, etc., to accomplish the task of suspending the pipe. There is thus a need for a simplified bracket that reduces the effort and number of components required to suspend the pipe. Further, there is a need for a bracket that reduces the time devoted to each individual pipe suspension point, and which reduces the number of instances during the construction process that each pipe hanger must be addressed to successfully suspend the pipe.
Ceiling hangers are known in which part of the hanger is removably fastened to a form for pouring the concrete and part of the hanger extends from the form so it is embedded in the concrete, as described in U.S. Pat. Nos. 1,362,245, 1,745,858, and 1,767,575. But in these prior art hangers the projecting hangers often present sharp or pointed ends that could hurt someone if they fall on the projecting ends, and the ends could be stepped on during construction and easily bent out of position. There is thus a need for a bracket that reduces sharp ends and that can be stepped on during construction without unacceptably deforming the bracket.


A gastric balloon includes a scaffold structure, one or more internal inflatable compartments within the scaffold structure, and one or more inflatable bladders formed over the space-filling compartment. The gastric balloon may be deployed transesophageally using a gastroscope and is inflated in situ, preferably using a combination of liquid and gas inflation media.

1. Field of the Invention
The present invention relates generally to medical apparatus and methods. More particularly, the present invention relates to the construction and use of gastric balloons for treating obesity.
Obesity is a serious medical condition and has become a widespread problem in the United States and many other industrialized countries. While many obese patients may be treated by modifications to diet and exercise, a number of morbidly obese patients are resistant to treatment and are candidates for surgical intervention. One surgical approach for treating morbid obesity is referred to as gastric or jejunoileal bypass where a major portion of the gastro-intestinal tract is surgically bypassed. While effective in some patients, gastric bypass procedures can have significant undesirable side affects. Moreover, the initial surgical procedure presents risks associated with open surgery. There are restrictive surgical procedures but they are less effective and still invasive. Consequently, an effective, non-invasive medical treatment with lower risks and minimal side effects is needed for many morbidly obese patients, who cannot tolerate surgical intervention, and most premorbidly obese patients, who have no effective treatment because their condition is not sufficiently severe to qualify them as surgical candidates.
As an alternative to such surgical procedures, the introduction of space-occupying structures into the stomach, often referred to as "gastric balloons," has been proposed. Such gastric balloons may be introduced through the esophagus and inflated in situ in order to occupy a significant volume within the stomach.
Although found to be effective in some cases, the use of gastric balloons has been compromised by a number of deficiencies. The most serious is a sudden or slow deflation of the gastric balloon that can allow the balloon to pass the pyloric valve and enter the intestines. Such unintentional passage of the deflated balloon into the intestines can cause intestinal obstruction and be life-threatening. Consequently, gastric balloons currently marketed outside the US are generally indicated for use of only up to six months.
The risk of deflation is exacerbated by the fact that the patient may not immediately be aware that the balloon has deflated, delaying the patient from seeing a physician. Thus, it would be desirable to provide approaches to allow a patient to detect leakage or impending leakage. Currently to detect leakage, some practitioners add methylene blue dye to the filling fluid, usually saline, prior to inflation. If the methylene blue leaks into the stomach, a blue color will be present in the patient's excrement. This procedure has a number of deficiencies as evidenced by the continued reports of significant rates of intestinal obstruction and excretion of deflated balloons in clinical practice. Slow and intermittent leaks can release such small amounts of dye that the dye is not detectable in the excrement. Faults on the medical professionals' part include mixing concentrations that makes detection unreliable or simply forgetting to mix in the substance prior to inflating the balloon. On the patients' side, many have difficulties detecting slight changes in the color of the excrement, forget to check diligently, or simply find the task psychologically too unpleasant to perform.
Other problems include infections resulting from bacterial colonization of the gastric balloon and lack of adequate sizing of the balloon prior to deployment in a patient's stomach. Additionally, most gastric balloons have been filled with saline or other liquid, making them heavy and uncomfortable within a patient's stomach. The weight of the balloons can cause them to induce gastric hypertrophy and create gastric erosions, ulcers, lesions and abrasions within the stomach at the points where they naturally rest.
For these reasons, it would be desirable to provide improved gastric balloon structures and methods for their use in treating obese patients. The balloons should be durable and the methods and apparatus will preferably be comfortable to the patient and in particular should avoid settling as a heavy weight in the patient's stomach. The gastric balloons and methods for their use should further prevent passage of an accidentally deflated balloon across the pyloric valve and into the intestines, even when the balloon structure is compromised and the balloon looses inflation medium. It would be further desirable if a deflation or impending deflation of the balloon were detectable to the patient in a rapid and reliable fashion. Such a detection system should alert the patient of failure and allow the patient to seek medical help before the balloon has deflated to a size that could pass the pylorus. The compromised device could be then removed or replaced on a timely basis. Additionally, it would be beneficial if the balloons were resistant to bacterial and other microbial growth, thus lessening the risk of infection upon long-term deployment. Other improvements would include balloons and methods for their deployment which allow for proper sizing the balloon and/or trimming or adjusting the balloon size even after deployment. At least some of these objectives will be met by the inventions described below.
2. Description of the Background Art
Gastric balloons and methods for their use in treating obesity are described in U.S. Pat. Nos. 6,746,460; 6,736,793; 6,733,512; 6,656,194; 6,579,301; 6,454,785; 5,993,473; 5,259,399; 5,234,454; 5,084,061; 4,908,011; 4,899,747; 4,739,758; 4,723,893; 4,694,827; 4,648,383; 4,607,618; 4,501,264; 4,485,805; 4,416,267; 4,246,893; 4,133,315; 3,055,371; and 3,046,988 and in the following publications: U.S. 2004/0186503; U.S. 2004/0186502; U.S. 2004/0106899; U.S. 2004/0059289; U.S. 2003/0171768; U.S. 2002/0055757; WO 03/095015; WO88/00027; WO87/00034; WO83/02888; EP 0103481; EP0246999; GB2090747; and GB2139902.