Knee protection system for the front passenger in a passenger car, having a glove compartment which is arranged below the dashboard or the cross tube, which is constructed as a hinged compartment and can be swivelled about an approximately horizontal axis and is provided with a latching device in the area of its free edge. Above the hinged compartment, a dimensionally stable hood is arranged which can be swivelled together with the hinged compartment. The hood is provided with a locking element which interacts with the latching device of the hinged compartment. In the area of the free edge, the hood is connected by means of tear-off elements with the dashboard. An air bag module is stationarily arranged above the hood behind the dashboard. A dimensionally stable element is connected with the dashboard and is used as an upper support for the inflated air bag, while the top side of the hood is used as the lower support.

This application claims the priority of German application 197 03 430.6 filed in Germany on Jan. 30, 1997, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a knee protection system for the front passenger in a passenger car, having a glove compartment which is arranged below the dashboard or the cross tube, which is constructed as a hinged compartment and can be swivelled about an approximately horizontal axis and is provided with a latching device in the area of its free edge.
For protecting the chest area and pelvic area of the front passenger in a passenger car, it is known to arrange an air bag module in the dash board which is activated in the case of a sudden acceleration because of an accident. Particularly when the front passenger is not wearing a seat belt, there is, however, the danger of injury to the knee and lower leg area. For reducing this risk, it would be conceivable to arrange an additional air bag module in the glove compartment. However, this would not only reduce the usable space of the glove compartment but would also make the operating of the glove compartment more difficult because of the additional weight of the air bag module. In addition, there is the danger that the swivelling of the glove compartment may damage the electric supply lines of the air bag module so that it will no longer be operative. Another possible measure for protecting the front passenger in the knee and lower leg region would be a special padding of the glove compartment. However, such a padding would considerably impair the freedom of movement of the legs.
It is an object of the invention to provide a knee protection system for the front passenger in a passenger car whose installation is not difficult, requires no valuable space and is distinguished by a high effectiveness while the operatability of the glove compartment is simultaneously maintained.
According to the invention, this object is achieved in that a dimensionally stable hood is arranged above the hinged compartment and can be swivelled together with the hinged compartment, in that an air bag module is stationarily arranged above the hood, in that a dimensionally stable element is connected with the dashboard and/or with the cross tube and acts as an upper support for the inflated air bag while the top side of the hood is used as the lower support, in that the hood is provided with a locking element which interacts with the latching device of the hinged compartment, and in that, in the area of the free edge, the hood is connected by means of tear-off elements with the dashboard or with the dimensionally stable element.
In the normal driving operation, the hood replaces the component which is normally mounted on the dashboard and which is provided with the locking element. This hood, the dimensionally stable element and the air bag module can therefore be installed in an existing vehicle type without any high-expenditure changes. When the air bag module is activated during a impact because of an accident, the air bag is inflated, in which case it is supported on the hood and on the dimensionally stable element. As soon as the predetermined holding force of the tear-off elements has been overcome, the hood together with the hinged compartment will swivel downward about the joint axis, and the air bag can inflate toward the rear into the passenger compartment. In this case, the hinged compartment moves toward the lower legs of the front passenger so that these can be supported early. Since the hinged compartment is locked to the hood and therefore no sharp edges are present, the risk of injury is reduced further. In addition, the content of the glove compartment is secured against falling out.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

Bayerische Motoren Werke Aktiengesellschaft


In one embodiment, a method includes writing data to a storage medium of a data storage system using a partial reverse concatenated modulation code by encoding data sets using a C2 encoding scheme, adding a header to each subunit of the data sets, encoding the headers of the data sets with a first modulation encoding scheme, encoding data portions of the data sets with a second modulation encoding scheme, encoding portions of the one or more C2-encoded data sets using a C1 encoding scheme, combining the C1-encoded portions with the modulation-encoded headers of the C2-encoded data sets using a multiplexer, and writing the one or more combined C1- and C2-encoded data sets to data tracks of the storage medium. Other methods for writing data to a storage medium of a data storage system using a partial reverse concatenated modulation code are presented according to more embodiments.

The present invention relates to data storage, and more particularly, to storing data using partial reverse concatenation that employs composite codes such as product codes and concatenated codes.
Efficient reverse concatenation of composite coding schemes is difficult to achieve. In general, reverse concatenation schemes have several advantages over other data storage techniques. Although reverse concatenation schemes employ large block sizes for modulation coding (MC) in order to achieve a high code rate and improve format efficiency, they do not suffer from error propagation because modulation decoding is performed after error correction coding (ECC) decoding. Moreover, reverse concatenation schemes allow the passing of soft information from the detector to the decoder thereby enabling the use of soft-decoding or iterative decoding techniques to improve error rate performance.
One reverse concatenation architecture for product codes performs conventional reverse concatenation in the sense that it reverses the order of ECC and MC. The rate of the modulation code in this approach is 0.9951 whereas the linear tape open (LTO) standard LTO-5 modulation code rate is 32/33=0.9697. Therefore, reversing the order of ECC and MC results in a 2.6% improvement in modulation code rate over the LTO-5 standard, thereby providing a higher tape format efficiency. The modulation code used in the above approach maintains the interleaved (I=11) modulation constraint satisfied in LTO-2 to LTO-5 tape drive standards. However, the G-constraint is weakened from G=14 in LTO-5 to G=22 due to the insertion of parity symbols by the column code which weakens the modulation constraints. Another significant drawback of the reverse concatenation scheme in the above approach is a high implementation complexity which exacerbates the use of this reverse concatenation architecture for product codes in actual practice. The existing reverse concatenation architecture for product codes requires a complete overhaul and redesign of existing data flow architectures which is prohibitively complex when backward compatibility must be provided. In addition to the implementation complexity, another drawback of the above approach is that C2 symbol insertion after MC weakens the achievable modulation constraints. Furthermore, this particular reverse concatenation scheme is not designed to satisfy non-uniform constraints. Therefore, the overall modulation constraints satisfied by this reverse concatenation scheme are not as tight as is desired. For any of these reasons, a system and technique which alleviates the problems associated with conventional reverse concatenation of product coding schemes would be very desirable.

This patent is subject to a terminal disclaimer.

Methods for partial reverse concatenation for data storage devices using composite codes

International Business Machines Corporation


Provided is a method for processing measured property data, such as property data that would be generated from measurement of a property of soil gas samples collected in a geochemical survey. Property data for individual components is processed to identify whether one or more of the components corresponds to a known contaminant material. When a portion of the property data is identified as corresponding to a contaminant material, then that portion of the property data is eliminated, and remaining property data is combined to form a composite for analysis purposes. Results of the analysis may be used to determine the location for drilling exploration or test wells to test for the presence of a targeted subterranean accumulation, such as of petroleum, natural gas, coal or an environmental pollutant.

Geochemical prospecting for subterranean accumulations of petroleum or natural gas based on analysis of collected soil gas samples is well known. Results of soil gas analysis provide information useful for evaluating the potential that a subterranean geologic structure may contain an accumulation of petroleum, natural gas or another targeted material. This information is helpful in selecting specific locations for further exploration evaluation, such as the drilling of exploration wells.
Various methods have been described for collecting and analyzing soil gas samples. One method for collecting and analyzing soil gas samples is described in U.S. Pat. No. 4,573,354. According to that method, soil gas samples are collected by adsorption of volatile soil gas compounds onto a carbon-coated ferromagnetic wire placed in holes in the ground. The adsorbed volatile compounds are then desorbed from each wire by heating the wire, using the Curie-point phenomenon. The desorbed compounds are swept into a mass spectrometer and a mass spectrum (referred to as a fingerprint) of the soil gas sample is obtained. A typical mass spectrum fingerprint of a soil gas sample collected above a petroleum reservoir is shown in FIG. 1.
The fingerprint provides some information concerning components of the soil gas sample. For example, mass peaks at m/z of 43, 57, 71, 85, and 99 have been shown to be associated with aliphatic hydrocarbons, while peaks at m/z of 91 and 105 have been shown to be associated with alkyl aromatic hydrocarbons. Also, a reference fingerprint obtained from an area over a known petroleum or gas reservoir may be compared with fingerprints of soil gas samples obtained from other geologically similar areas to identify exploration locations with a high potential for the presence of petroleum or natural gas. A preferred method of comparison according to the method of U.S. Pat. No. 4,573,354 is a multivariate statistical analysis, although other comparison techniques may also be used.
One problem that has been discovered with the method disclosed in U.S. Pat. No. 4,573,354 is that there is often one or more contaminant component(s) in the soil gas samples that may distort the mass spectrum, thereby impairing the accuracy with which the mass spectrum can be analyzed and, accordingly, the reliability of the analytical results as an indicator for the presence of the targeted material. In this regard, a contaminant component may be a naturally-occurring or human-introduced compound that is not associated with or indicative of underlying geologic features. For example, terpenes are naturally-occurring compounds that come from vegetation. The presence of terpenes in a soil gas sample can significantly interfere with accurate analysis of the soil gas mass spectrum. An example of a human-introduced contaminant is trichloroethane, which is widely found in aquifers due to its extensive use as a cleaning solvent. The presence of trichloroethane in a soil gas sample can significantly impair the accuracy of analysis. There is a significant need for a method to reduce the detrimental interference that may be caused by the presence of these and other contaminants.

Method and apparatus for processing geochemical survey data


Systems and methods that make use of logical partitions of a second tier of disk storage at a disaster recovery (DR) site remote from a production site as part of a DR setup to advantageously reduce disruption to production site data production operations during DR procedures while providing for the substantially immediate recall or retrieval of data previously migrated to the remote second tier of disk storage.

1. Field of the Invention
The present invention generally relates to the use of virtual tape libraries (VTLs) for use in disaster recovery (DR) of enterprise production data and, more specifically, to manners of migrating production data from a local VTL to one or more logical partitions of a remote, second-tier disk storage system such as a virtual library extension made up of virtual multi-volume cartridges (VMVCs) holding a plurality of virtual tape volumes (VTVs).
2. Relevant Background
Businesses and other organizations rely on data processing systems to manage a wide range of internal and external functions, including accounting and inventory functions, data management functions, and many others. Many of these systems must be available to be accessed over local or wide-area data processing system networks, including both private networks and public networks such as the Internet.
Data processing systems are often used in conjunction with hierarchical storage management (HSM). Generally, HSM is a data storage technique that monitors the way data is used and functions to move data between two or more "tiers" of storage. "Tiered storage" is a data storage environment made up of two or more kinds of storage that are delineated by differences in at least one of price, performance, capacity and function. For example, hard disk drive arrays and magnetic tape could represent first and second tiers of storage as hard disk drive arrays are associated with higher speed, higher cost and lower capacity while magnetic tape is associated with lower speed, lower cost and higher capacity. As another example, one type of hard disk storage associated with higher speed and lower capacity could be a first tier, another type of hard disk storage associated with lower speed and higher capacity could be a second tier, and a tape library storing tape drives (each of which reads and writes data on a length of magnetic tape) could be as third tier.
In a typical HSM scenario, frequently used data files are stored on a first storage tier (e.g., disk drives) but are eventually transferred or "migrated" to a second or additional storage tiers (e.g., tape) if they are not used after a certain period of time (e.g., a few months). Generally, data migration involves mapping data between storage tiers so as to provide a design for data extraction and data loading between the storage tiers (e.g., to relate data formats between the storage tiers). In any event, data may be automatically moved back to higher tiers (e.g., the first tier) if a user desires to reuse a file on a lower tier.
Long term data storage has traditionally involved use of storage tiers including tape drives due to the favorable unit cost and long archival stability of magnetic tape. Magnetic tape is often stored on removable tape cartridges which allows for the tape to be taken to off-site locations to provide for disaster recovery. A plurality of tape cartridges can be stacked to form a multi-volume cartridge (MVC).
While magnetic tape media presents favorable unit cost and long archival stability, many enterprises and other users desire for more "tape-less" data storage due to long recovery periods, security considerations, the onerous task of implementing non-full restores (e.g., non-sequential restores), and the like. However, many or most mainframe systems still require compatibility with tape drives as part of data storage and archiving. In this regard, VTLs (such as Oracle's Virtual Tape Storage Subsystem (VTSS)) are now being used, each of which is generally in the form of a hard disk storage system that emulates tape libraries or tape drives for use with existing backup software. VTLs generally make use of VTVs which are direct access storage device (DASD) buffers that appear to the operating system as a real tape volume. Data can be written to and read from a VTV and the VTV can be migrated to and recalled from real tape volumes. Multiple VTVs can be stored within a virtual MVC (VMVC).
In the event of a "disaster," which can include both actual natural disasters and other events, a primary system at a production site may be "down" or otherwise unavailable leading to disruption of operations, lost revenue, and the like. In this regard, many businesses and other enterprises maintain or otherwise implement DR systems or operations which broadly include redundant systems that provide some or all of the functions of the primary systems and typically include full backups of all the data available to the primary systems. In this way, users can, in the event of a disaster, transition to the DR environment until the primary system can be restored, thus reducing lost productivity.
A DR strategy generally has a number of basic components such as migrating or otherwise moving data from a production site to one or more storage tiers or systems of a DR site (e.g., typically at a location that is geographically remote from the production site, such as a different city, different state, and the like), testing one or more DR plans, deploying the DR plan(s) in the event of an actual disaster, and returning to normal operations after a DR test or actual disaster. Testing the recoverability of data and/or software allows the user to validate that its personnel, its information technology (IT) infrastructure, the host software and the storage product itself can handle an unexpected disaster. For instance, the production site of a particular DR setup may include one or more production hosts along with a number of storage tiers and the DR site of the DR setup may be located at a remote distance from the production site and also include one or more storage tiers. Data written to the production storage tiers may also be replicated to one or more storage tiers at the DR site thus providing a secondary copy of the data in the event the production site data or software is lost.
FIG. 1 illustrates a schematic diagram of one type of DR setup 100 made up of a production site 104 and a remote DR site 108 and including the use of one or more VTLs. The production site 104 includes a host 112 (e.g., mainframe) including any appropriate operating system (not shown) that is operable to generate or otherwise manipulate production data. The host 112 includes a host software component (HSC) 116 (e.g., such as Oracle's Virtual Tape Control System (VTCS)) that is broadly operable to create VTVs from the production data and administer migration of the VTVs from host 112 to a first storage tier such as VTL 124 (e.g., such as Oracle's Virtual Tape Storage Subsystem (VTSS)) according to any appropriate enterprise policies (e.g., upon production data being created, according to any appropriate schedule, and the like). Even though the production data is being stored on disk drives on the VTL 124, the HSC 116 interacts with the VTL 124 as if the data is being stored on actual tape drives.
As part of the generation and migration of production data to the VTL 124, one or more production control data sets (CDSs) 120 may also be generated and stored in any appropriate manner. Once a copy of the production data is stored in VTVs in the VTL 124, additional copies of the VTVs are migrated according to any appropriate migration policies (e.g., according to data type, percentage of VTL 124 occupied, any appropriate schedule, and the like) to one or more second storage tiers such as a local tape library 128 and a tape library 132 at the DR site 108 (e.g., via a channel extension). Upon declaration of a disaster at the production site 104 as part of a DR test, the VTV copies stored in the tape library 132 can be recalled to a first tier storage system at the DR site 108 such as VTL 136 at the DR site 108.

Logically partitioning remote virtual library extensions for use in disaster recovery of production data


A method and apparatus are provided for evaluating a quality, as perceived by a recipient, of a signal carrying a stimulus. The method includes a step for detecting absences of variation of said signal and a step of quantifying at least one deterioration corresponding to an absence of variation. The quantity of deterioration computed during the quantification step depends on an amplitude of variation of the stimulus immediately following the concerned absence of variation. The method and apparatus enable the correlation of the duration of variance, possible past of invariances and a sudden variation of amplitude following said in variance, in implementing an automatic technique in real time, for example.

Targeted distribution systems whose use is possible in the present state of the art generally make use of a conversion of an analog signal, representing stimuli to be transmitted, into a digital data signal. Said conversion is usually followed by an encoding of said data in order to reduce the volume as far as possible without thereby in any way causing this data to suffer significant deterioration. The encoded data is designed to be transmitted by packets according to standardized transmission protocols such as the Internet IPv4 or IPv6 protocols. It has to be recognized however that, although these packet transmission protocols offer considerable advantages, which is what has made them successful, they are intrinsically a source of deterioration caused by the inevitable loss of certain data packets. Furthermore, whatever the chosen encoding technique, the goal would be a compression that cannot be obtained except by eliminating certain characteristics, deemed to be superfluous, of the stimuli to be encoded. Such compression would inevitably generate losses which could have a negative impact on the perception that a recipient will have of the stimuli transmitted to him in encoded form.
Now an individual who, for example, has subscribed to a service for the supply of audiovisual programs will be contractually entitled to expect a minimum level of quality of the images and sounds that are transmitted to him or her, so that a provider of this supply service would have to ensure that such demands are properly met. This cannot be achieved except by carrying out a relevant evaluation of the quality of the stimuli which will be restored to the recipient after transmission. This evaluation would have to be done in taking account of the specific human features of this recipient's faculties of perception.
Various methods have already been elaborated in the past for the separate evaluation of a quality of a signal carrying a stimulus such as a moving picture or a sound. These methods make use for example of a group of persons each of whom has to be exposed to said stimulus and is then requested to assign a grade representing its quality as this person would have perceived it. However, such methods require major logistics and are therefore costly to implement since they require that persons should be brought together in a controlled environment such as a test laboratory in a number sufficient so that a statistical mean of the grades assigned is effectively representative of a mean perception. Furthermore, such methods cannot be used for real-time measurement of quality as perceived by a subscriber at the reception of a stream of stimuli that he would have commanded, so that these methods are not adapted as such to quality control applications in the above-described systems for the targeted distribution of information.
It has also been noted, in the implementation of such methods, the perception that certain types of deterioration could have an impact, on the perception of a person, that cannot be totally decorrelated from a chronological context in which such a deterioration was made to occur. Among other harmful effects, a loss of one or more data packets could cause a discontinuity taking the form of a break in the fluidity of video sequences or a break in a sound signal. This is because, in the event of interruption or appearance of delays in a stream of data packets received by a reception decoder, a receiver usually provides a restoration in a loop of a same stimulus defined by data contained in a buffer memory included in this receiver, so that this stimulus will then be essentially invariant unto the new data packets enable a new stimulus to be reconstituted.
It has been observed that the impact of such discontinuity on the perception of the quality of a stimulus that a person exposed to this stimulus would have would be made to vary as a result firstly of the duration of this discontinuity and secondly of the number of discontinuities having previously affected this same stimulus and therefore having also been previously observed by this same person.
An article "FRAME DROPPING EFFECTS ON USER QUALITY PERCEPTION" published in a report of a WIAMIS conference in Lisbon in April 2004 thus proposes a method of automatic computation of a measurement quantity specifically intended to represent the impact, as perceived by a person exposed to a video signal, that would be produced by discontinuities in a data stream representing this video signal. This method enables the quantifying of a combination of the effects, firstly, of a unitary deterioration caused by each discontinuity and depending on the duration of this discontinuity and, secondly, a possible accumulation of such discontinuities.
The work by the inventors however has shown that a poor impression felt by a person exposed to an invariance of a stimulus depends not only on the duration of this invariance and possible preliminary invariances but also on the conditions in which the invariance disappears to the benefit of a resumption of a normal running of the exposure to the stimulus. This tends to show that the approach described here above is not entirely satisfactory.

Method and device for evaluating degradation of quality caused by an invariance of a stimulus, as perceived by a recipient of said stimulus


Methods and systems are described herein for populating application-specific information using overlay applications. For example, in order to relieve some of the difficulties users face in inputting information into mobile devices which may have smaller screen sizes and may not feature dedicated input mechanisms, the methods and systems described herein automatically populate application-specific information. The methods and systems do this using an application that presents an application overlay feature. That is, the application is accessible while a user is using another application (e.g., on the mobile device) and/or while a user is scrolling through other applications.

In recent years, the amount of content and functions available on mobile devices has increased exponentially. Moreover, users are increasing using mobile devices to perform functions previously done on stationary computer devices with dedicated input mechanisms (e.g., mouse controls, keyboards, remote controls, etc. As users migrate to performing functions on mobile devices, users face difficulties as mobile devices may have smaller screen sizes and may not feature dedicated input mechanisms.

Methods and systems for populating application-specific information using overlay applications


A pressure gauge and indicator switch wherein a Bourdon tube and electrical switch are sealably contained within a liquid-filled compartment, and a liquid pathway is provided between the Bourdon tube and an external fitting. The electrical switch leads are connectable outside the compartment, and the Bourdon tube is mechanically linked to a pressure indicator so as to provide an analog reading of actual pressure within the Bourdon tube, and the Bourdon tube is mechanically linked to the pressure switch so as to provide a switch actuation whenever the pressure within the Bourdon tube reaches a predetermined level.

The present invention relates to measurement and control systems for the delivery of liquids under relatively high hydraulic pressures. In particular, the invention relates to a liquid pressure gauge having an indicator for providing a direct readout of pressure, and having an internal electrical switch which may be activated at certain predetermined pressures.
Pressure gauges for monitoring the pressures within a hydraulic delivery line are well known. Such pressure gauges are typically interposed into the liquid delivery conduit so as to be in direct contact with the pressurized liquid therein. A pressure-responsive element typically includes a transducer which translates liquid pressure into a physical movement, and the physical movement is mechanically linked to an indicator device. The pressure gauges which are known in the prior art include pressure gauges wherein a Bourdon tube has an opening which is in contact with the pressurized liquid, and also includes liquid-filled Bourdon tubes wherein the liquid is sealed into the tube by means of a movable diaphragm sealing disk mounted at the end of the Bourdon tube, wherein the end of the Bourdon tube is then placed in a liquid delivery conduit so as to be exposed to liquid pressures therein via the diaphragm.
Pressure control switches are also known, wherein an electrical switch activation lever is placed in proximity to a Bourdon tube pressure sensor, wherein pressure changes cause the Bourdon tube to deflect and move the switch actuator, thereby generating an electrical signal at the pressure level at which contact is made. U.S. Pat. No. 4,323,741, issued Apr. 6, 1982, and U.S. Pat. No. 4,397,610, issued Aug. 9, 1983, disclose two forms of pressure-control device wherein these principles are used.


Pharmaceutical compositions suitable for oral administration comprising paclitaxel, a solvent, a surfactant, a substituted cellulosic polymer, and optionally but preferably a P-glycoprotein inhibitor. The composition may further comprise a diglyceride or mixture of diglyceride and monoglyceride. The composition generates a supersaturated paclitaxel microemulsion upon contact with water resulting in improved oral bioavailability of paclitaxel.

Paclitaxel is a clinically effective chemotherapeutic agent approved for the treatment of various cancers. However, because paclitaxel has very low water solubility (˜10 μg/ml) which, due to a lack in suitable chemical functionality for salt formation, cannot be increased by pH adjustment, formulation of paclitaxel has proven difficult. As a result, most of the formulation work known in the art has been based on the use of co-solvents, surfactants and excipients (i.e., cyclodextrin) for intravenous (IV) formulations. Further, the oral bioavailability of paclitaxel has also been reported to be very low and as a result there is no oral formulation of paclitaxel on the market.
One of the commercially available intra-venous (IV) paclitaxel formulations is marketed under the trade name of Taxol® by Bristol-Myers/Squibb. Taxol® contains 6 mg/ml of paclitaxel, 527 mg/ml of a surfactant, (Cremophor EL, a polyethoxylated castor oil), and 49.7% (v/v) of absolute ethanol. This formulation requires a 5 to 20 fold dilution with either 5% dextrose or 0.9% NaCl solution which is then delivered by an intravenous infusion into the patient. Because of the low drug content in the Taxol formulation, a large volume of the formulation is administered to the patient in order to provide the required therapeutic doses (˜135-170 mg/m2). It is also worth noting that the amount of Cremophor EL necessary to deliver the required dose of paclitaxel in the Taxol formulation is considerably high (88 mg Cremophor EL per mg paclitaxel) and this vehicle has caused serious, life-threatening anaphylactoid reactions in animals and humans, even without paclitaxel. In addition, it has also been noted that that the Cremophor/ethanol formulation of paclitaxel precipitates upon dilution with infusion fluid and that fibrous precipitates are formed in some compositions when stored for extended periods of time. Additional information regarding disadvantages of paclitaxel compositions containing high concentrations of Cremophor may be found in U.S. Pat. No. 5,504,102 to Agharkar et al.
To alleviate the severe side-effects of the paclitaxel/cremophor formulations, patients are often required to receive premedication and/or prolonged paclitaxel infusion duration time of up to 24 hours. These measures, however, carry significant disadvantages. For example, the long infusion duration is inconvenient for patients, and is expensive due to the need to monitor the patients for the entire 6 to 24-hour infusion duration and the patient's prolonged stay in a hospital or treatment clinic. Similarly, premedication increases patient discomfort and increases the expense and duration of treatment. Moreover, such measures normally would not completely eliminate the side effects.
U.S. Pat. No. 5,641,803 to Canetta et. al. discloses a method of administering paclitaxel dosages of about 135 mg/m2 via infusions of less than 6 hours duration. This method requires pretreatment of the patients with steroids, antihistamines, and H2-receptor antagonists sufficient to prevent fatal anaphylactic-like reactions.
U.S. Pat. Nos. 6,136,846 and 6,319,943 disclose an oral formulation of paclitaxel which comprises paclitaxel, a solvent, and a pharmaceutically-acceptable, water-miscible solubilizer forming micelles, the solubilizer being selected from the group consisting of solubilizers having the general structures: R1 COOR2, R1 CONR2, and R1 COR2, wherein R1 is a hydrophobic C3-C50 alkane, alkene or alkyne and R2 is a hydrophilic moiety and wherein the solubilizer is selected such that it does not have a pKa less than about 6. The concentration of paclitaxel in the composition disclosed in U.S. Pat. Nos. 6,136,846 and 6,319,943 is 5-20 mg/g.
U.S. Pat. No. 5,648,090 to Rahman et. al. discloses a liposomal-encapsulated paclitaxel or an anti-neoplastic derivative thereof that is used to effect a therapeutically enhanced method of treating cancer, and may be used advantageously in combination with hyperthermia. The liposomes confer enhanced stability and solubility characteristics to paclitaxel or derivatives thereof.
U.S. Pat. No. 5,424,073 to Rahman et. al. discloses a liposomal-encapsulated paclitaxel or an anti-neoplastic derivative thereof which comprises a liposome forming material, cardiolipin, paclitaxel and a pharmaceutically acceptable carrier. The liposome forming material is phosphatidyl choline, cholesterol, and the like and the liposomes formed thereby may have a positive, negative or neutral charge. The liposomes confer enhanced stability and solubility to paclitaxel or derivatives thereof.
U.S. Pat. No. 6,090,955 to Reszka et. al. discloses a liposome-encapsulated paclitaxel composition that consists of a high paclitaxel concentration with high stability and hence a high therapeutic effect. The invention involves the development of specific forms of paclitaxel encapsulation and the use of these, optionally in combination with other substances, in the treatment of various types of tumor. The liposome consists of a lipid, an amphiphillic material, a polymer and a carrier liquid. The liposome-encapsulated paclitaxel is characterized in that it is prepared by high-pressure homogenization or by aerosol formulation.
U.S. Pat. No. 5,415,869 to Straubinger et. al. discloses a pharmaceutical composition for use in treatment of cancer patients comprised of at least one taxane and a mixture of one or more negatively charged phospholipids and one or more zwitterion (i.e. neutral) phospholipids. This mixture entraps the taxane in what is believed to be a liposome. The mixture contains a ratio of negatively charged phospholipids to zwitterion phospholipids of 1:9 to 7:3. The paclitaxel is present in an amount of 1.5-8.0 mole percent taxane. The composition is in the form of particles having a size of 0.025 to 10 microns with substantially no taxane crystals. One of the negatively charged phospholipids is diphosphatidyl choline, i.e. cardiolipin.
U.S. Pat. No. 5,683,715 to Boni et. al. discloses liposomal taxane formulations where the liposomal lipid is a phosphatidylcholine; these formulations are useful for treating animals afflicted with cancers.
U.S. Pat. No. 5,728,687 to Bissery discloses pharmaceutical compositions having therapeutic synergy comprising paclitaxel or taxotere or analogues thereof combined with at least one other therapeutically useful substance for treating neoplastic diseases. The other therapeutic substance is selected from the group consisting of an alkylating agent, epidophylloptoxin, an anti-metabolite or a vinca alkaloid.
U.S. Pat. No. 6,096,331 to Desai et. al. discloses and claims compositions and methods that are useful for the in-vivo delivery of taxane, wherein the taxane is formulated with a polymeric biocompatible material such as human serum albumin. The compositions are substantially cremophor-free and a variety of neoplastic tumors are treatable thereby.
U.S. Pat. No. 5,908,835 to Bissery discloses anti-tumor compositions comprising paclitaxel, taxotere or their derivatives in combination with an anthacycline antibiotic, the combination having a synergistic pharmacological activity greater than the expected additive effect of its individual components.
U.S. Pat. Nos. 5,665,382 and 4,498,421 to Grinstaff disclose and claim pharmaceutical compositions in which an active agent is encapsulated within a polymer shell whose cross-sectional dimension is no greater than 10μ. The shell consists of a biocompatible material such as proteins, lipids, polysaccharides and polynucleic acids all of which possess sulfhydryl groups that are cross-linked to form the shell. The pharmaceutical agent is any one of a number of generically disclosed groups excluding anti-cancer compounds.
U.S. Pat. Nos. 5,916,596 and 5,439,686 to Desai et. al. disclose pharmaceutical compositions comprising emulsions of polymer-encapsulated pharmaceutical agents including protein encapsulated paclitaxel. The polymer is a protein, polysaccharide, polypeptide or polynucleic acid cross-linked by disulfide bonds. The emulsion is any one of a wide variety of organic solvents.
Accordingly, there exists a clear need for oral compositions of paclitaxel that are easy to prepare, contain a high concentration of paclitaxel but a low surfactant level, cause fewer side effects, have improved stability and have high oral bioavailability.

Chemotherapeutic microemulsion compositions of paclitaxel with improved oral bioavailability


The present invention relates to Compound T62, pharmaceutically acceptable salts thereof, and their use in medicine as allosteric adenosine A1 receptor enhancers and uses including treatment of pain, for example, persistent chemical pain, neuropathic pain and acute pain states such as that induced by chemical irritation, gastrointestinal disturbance, migraine and all forms of headache. Compound T62 is represented by the formula:

The present invention relates to methods and compositions for treating various forms of pain in mammals. Although the present invention is expected to be useful for virtually all pain types, it is most potent for pain involving hypersensitivity of the nociceptive pathway such as inflammatory pain, persistent chemical pain, and neuropathic pain. At higher doses, the present invention is also effective in acute pain states such as that induced by chemical irritation, gastrointestinal disturbance, migraine and all forms of headache.
Inflammatory pain can occur when tissue is damaged, as can result from surgery or due to an adverse physical, chemical or thermal event or to infection by a biologic agent. Although inflammatory pain is generally reversible and subsides when the injured tissue has been repaired or the pain inducing stimulus removed, present methods for treating inflammatory pain have many drawbacks and deficiencies. Thus, the typical oral, parenteral or topical administration of an analgesic drug to treat the symptoms of pain or of, for example, an antibiotic to treat inflammatory pain causation factors can result in widespread systemic distribution of the drug and undesirable side effects. Additionally, current therapy for inflammatory pain suffers from short drug efficacy durations which necessitate frequent drug re-administration with possible resulting drug resistance, antibody development and/or drug dependence and addiction, all of which are unsatisfactory. Furthermore, frequent drug administration increases the expense of the regimen to the patient and can require the patient to remember to adhere to a dosing schedule.
Chemically induced pain may occur when a patient is exposed to chemical agents that trigger pain response. Commonly, chemical pain is used to test anesthetic or analgesic efficacy of treatment methods.
Some examples of neuropathic pain are diabetic neuropathy, post-herpetic neuralgia (shingles), trigeminal neuralgia, pain associated with AIDS infection and treatment, whip-lash pain, pain due to cancer treatment, phantom limb pain, traumatic injury, complex regional pain syndrome and pain due to peripheral vascular disease.
The development of hyper-excited sensory nerve function has been described by Sollevi 1997 (1). These symptoms are often manifested as neuropathic pain. Neuropathic pain is a persistent, chronic pain usually described as a burning, shooting or lancinating sensation without an obvious cause. These symptoms are often associated with damage to nerves or nerve fibers. Such pain is associated with the transmission of abnormal pain signals from injured peripheral nerves to neurons in the brain and spinal cord. Briefly, the sensory nervous system projects signals to the central nervous system (CNS), mediating information from the periphery to the brain. These comprise signals from sensors in peripheral tissues and other organs, sensitive for qualities like touch, temperature changes, vibration, painful stimuli, pressure, vision, hearing, smell, taste and balance. This sensory nervous system is an important physiological control in the subject""s relation to the environment.
The sensory nervous system can be damaged by various types of trauma, such as infections and mechanical lesions including whip-lash injury, diseases such as diabetes and HIV infection, cancer or HIV treatments. This can result in disturbance in the signal transmission into the CNS, leading to reduced perception of sensory signals (hypoestesia) as well as hyper-function (more excited signals in the CNS) due to some largely unknown changes in the nerve transmission process (neuropathic damage). The neuropathic condition with hyper-excitation is described as a xe2x80x9cwind-upxe2x80x9d phenomenon and often involves several of the above mentioned sensory functions.
This may therefore be associated with decreased thresholds for touch and temperature (hyperesthesia), discomfort in the perception for touch and temperature (dysesthesia), discomfort or pain with touch, pressure and/or temperature stimulation (allodynia), and hypersensitivity to pain stimuli (hyperalgesia), balance disturbance, disturbance of auditory type (tinnitus) as well as ganglionic dysfunction. These types of hyper-reactive sensory nerves may develop after various types of trauma, and are called chronic when persistent for more than 3-6 months.
Adenosine, administered intravenously or intrathecally, has been proposed as a treatment for this sensory nerve hyper-reactivity (1, 2, 3). The objective of the treatment is to restore a normal perception of pain, as well as other sensory functions, in patients suffering from pathological hyper-excitation due to nerve damage.
Similarly adenosine has been proposed as treatment for other pain states derived from nociception including acute pain, tissue injury pain and nerve injury pain (15). Adenosine modulates the pain response by stimulating A1 adenosine receptors present in the dorsal root of the spinal cord and higher brain centers (spraspinal mechanisms) (14). A1 agonists have been shown to be effective treatment for every pain type in animal pain models (see Table 2 of, Yaksh, 1999, reference 15). However, A1 agonists also cause cardiovascular side effects and CNS side effects such as heart block, hypotension and sedation.
Adenosine is an endogenous nucleoside present in all cell types of the body. It is endogenously formed and released into the extracellular space under physiological and pathophysiological conditions characterized by an increased oxygen demand/supply ratio. This means that the formation of adenosine is accelerated in conditions with increased high energy phosphate degradation. The biological actions of adenosine are mediated through specific adenosine receptors located on the cell surface of various cell types, including nerves (4). The hyper-reactive nerves increase adenosine release due to an increase in metabolic activity.
A1 receptors are widely distributed in most species and mediate diverse biological effects. The following examples are intended to show the diversity of the presence of A1 receptors rather than a comprehensive listing of all such receptors. A1 receptors are particularly ubiquitous within the central nervous system (CNS), with high levels being expressed in the cerebral cortex, hippocampus, cerebellum, thalamus, brain stem, and spinal cord. Immuno-histochemical analysis using polyclonal antisera generated against rat and human A1 adenosine receptors has identified different labeling densities of individual cells and their processes in selected regions of the brain. A1 receptor mRNA is widely distributed in peripheral tissues such as the vas deferens, testis, white adipose tissue, stomach, spleen, pituitary, adrenal, heart, aorta, liver, eye, and bladder. Only very low levels of A1 receptors are thought to be present in lung, kidney, and small intestine.
The present invention relates to a class of compounds known as allosteric modulators or allosteric enhancers. Prior to the present invention and its parent (U.S. patent application Ser. No. 09/654,994), allosteric enhancers have only been described for the A1 adenosine receptor (5, 6, 7). No allosteric modulators had been proven effective in neuropathic pain models at any concentration. A1 the currently known enhancers are derivatives of the 2-amino-3-benzoylthiophenes first described by Bruns et al. (5). These benzoylthiophenes are not agonists at the endogenous A1 adenosine receptor (5, 6, 8). Structurally, all known agonists for the A1 adenosine receptor are derivatives of adenosine. The presence of an unmodified ribose ring is essential for agonist activity at the A1 adenosine receptor (9). Benzoylthiophenes are not agonists at the A1 adenosine receptor. Importantly, these compounds are antagonists at the A1 adenosine receptor (5, 6, 7, 8). At low concentrations, these benzoylthiophenes enhance the effect of agonists. At higher concentrations, these compounds act as antagonists. Therefore, the concentration range where these compounds can enhance the effects of agonists is limited (8).
Mechanistically, benzoylthiophenes appeared to enhance A1 adenosine receptor function by stabilizing the high affinity state of the receptor-G-protein complex (8, 10). This property is manifested as an increase in high affinity binding in radioligand binding reactions where an agonist radioligand is used to label the A1 adenosine receptor. An enhancer that increases agonist binding can do so by either accelerating the association of agonist and receptor, or by retarding the dissociation of the xe2x80x9creceptor-ligandxe2x80x9d complex. Kinetic studies have shown the benzoylthiophenes to retard the dissociation of the xe2x80x9creceptor-ligandxe2x80x9d complex. In contrast, an agonist, or an antagonist will both compete with the radioligand for the binding site and accelerate the dissociation of the xe2x80x9creceptor-ligandxe2x80x9d complex (8). Since the benzoylthiophenes only selectively retard the dissociation of the xe2x80x9creceptor-ligandxe2x80x9d complex when an agonist radioligand is used, the benzoylthiophenes must bind to a site different from the agonist recognition site. This putative site is termed the allosteric site, and presumably, compounds that bind to this site and enhance the agonist effect are termed xe2x80x9callosteric enhancersxe2x80x9d.
Another challenge is that that wide distribution of adenosine receptors offers both opportunities and drawbacks for therapeutic intervention. As an example, A1 adenosine receptors are found in the CNS, in heart and adipose tissue. Thus, agonists are capable of reducing free fatty acid levels in the blood through their interaction with adenosine A1 receptors on fat cells. This is a useful feature in non-insulin dependent diabetes mellitus. However, the concomitant bradycardia and drop in mean arterial pressure due to interference with cardiovascular adenosine receptors are to be considered as serious side effects.
In the U.S. patent application Ser. No. 09/654,994, Compound T62 is disclosed in the parent application as being a potent allosteric adenosine A1 receptor antagonist. However, as disclosed, Compound T62 is used in relatively low dosages and as such is most effective in the treatment of neuropathic pain.
An object of the present invention is to provide a therapeutically useful enhancer with improved potency as an enhancer, and preferably, without antagonist property. The present invention describes the discovery of a compound that meets these criteria.
The present invention relates to a composition and a method for the treatment of hyper-excited sensory nerve functions, e.g., neuropathia in human subjects. The treatment method comprises oral administration, topical administration, subcutaneous administration, intravenous administration, or intrathecal administration of an allosteric enhancer at the adenosine A1 receptor.
It is demonstrated that (2-Amino-4,5,6,7-tetrahydrobenzo[b]thiophen-3-yl)(4-chlorophenyl)methanone (Compound T62) normalized hyper-excited sensory nerve functions in a model of neuropathic pain in low dosage levels.
Surprisingly, it has been found that Compound T62 is well tolerated in animals at high dosages. At these higher dosages the allosteric enhancer effect of Compound T62 can be applied to treat other pain mechanisms as well as treating neuropathic pain with higher dosages.
The method of treatment comprises enteral, dermal, parenteral or subcutaneous administration of an effective amount of Compound T62, an A1 allosteric enhancer, to the patient. Another object of the present invention is to provide a composition comprising an adenosine A1 allosteric enhancer for the manufacture of a medicament for alleviation or normalization of a pathologically hyper-excited sensory nerve function in a conscious human subject. The invention further relates to a pharmaceutical preparation for alleviation or normalization of a pathologically hyper-excited sensory nerve function in a conscious human subject, comprising a selected allosteric enhancer for the adenosine receptor in a pharmaceutically acceptable carrier.
Accordingly, the invention provides a method using an allosteric enhancer for the A1 adenosine receptor as a means to reduce or eliminate neuropathic symptoms in human subjects. An allosteric enhancer for the A1 receptor is preferably administered orally in a tablet, capsule, suspension or other suitable oral dose forms. More rapid pharmacologically effect may be elicited by parenteral administration. For parental administration, it may be administered in a central vein or preferably in a peripheral vein, by a bolus injection. If desired, an allosteric enhancer can also be given intrathecally.
When given orally, a dose range of 100 mg to 1000 mg (approximately 1 to 15 mg/kg free base per dose) can be given to a patient. Doses given parentally will be in the range of 0.01 to 1 mg/kg). This treatment can be individually repeated at regular intervals. The invention is a new principle for alleviation of hypersensitivity of the sensory nerve system e.g. such as the perception of touch, temperature, vibration, pain and pressure on the skin. The invention further applies to alleviation of hyperfunction of other functions, e.g. visual function, auditory function, olfactory function, taste, balance and ganglionic transmission.


Various embodiments may relate to a dimming drive circuit for an illumination apparatus and an illumination apparatus including the dimming drive circuit, wherein the dimming drive circuit includes a filter circuit unit and a bleeder circuit unit, a main control module connected to the filter circuit unit and the bleeder circuit unit, respectively, and an auxiliary control module configured to reduce the current of the bleeder circuit unit and/or to switch off the bleeder circuit unit according to a characteristic input current of the dimming drive circuit prior to switch-off of the bleeder circuit unit by the main control module in a first operation state of the dimming drive circuit, and to prevent the filter circuit unit from releasing electrical energy via the bleeder circuit unit in a second operation state of the dimming drive circuit.

In the existing drive devices of an illumination apparatus, the dimming control is usually performed for the illumination apparatus with a phase cut dimming method. The illumination apparatus, for which the dimming is controlled according to the phase cut dimming method, not only can effectively and quickly control the luminous brightness of the illumination apparatus and save the electrical energy to a certain extent, but also has a low cost due to the simple structure and manufacture of the drive device having the phase cut dimming function. The drive device having the phase cut dimming function not only has a high power factor, but also is compatible with a leading phase cut dimming circuit or a trailing phase cut dimming circuit. Besides, this drive device also can operate in a quick response (QR) mode, or operate in a boost-buck mode or in flyback mode. However, the existing drive devices having the phase cut dimming function will increase the power consumption of a bleeder circuit due to connection to a dimmer, and thereby increase the power consumption of the entire integrated circuit to bring about unnecessary power loss to the illumination apparatus.

Dimming drive circuit and illumination apparatus including the dimming drive circuit


This invention relates to a method of altering the electrical characteristics of a material through a laser ablation process. It can achieve high doping levels and shallow junctions at low temperatures, which are desirable in the fabrication of thin film transistors.

Thin film silicon technology has been widely used in large-area high-resolution liquid crystal display panels ("LCDs") and 2-dimensional image sensor arrays, both of which have a similar matrix of pixels. Generally, the pixels are defined by the intersection of metal lines which are connected to the gate and drain of a thin film transistor ("TFT"). When a voltage pulse is applied to the gate lines, electrical charge is transferred from the pixels to the output lines or vice versa. In an LCD, each pixel contains a TFT and a capacitor which causes the liquid crystal molecules to rotate when the capacitor is charged. In a sensor array, each pixel contains a TFT and an amorphous silicon p-i-n diode which stores electrical charges created by light and outputs the charges to an external read-out electronics when the TFT is switched on. The ability to fabricate smaller and faster TFTs is a key element in improving the resolution and the response time of large-area displays or sensors.
In order to make faster and smaller TFTs, it is necessary to form shallow and highly doped regions under the source and drain electrodes of a TFT. Shallow and highly-doped source and drain regions produce smaller device geometry, lower contact resistance, and lower junction capacitance, all of which in turn result in higher aperture ratio and better response time.
A commonly used technique to dope a semiconductor material is by ion implantation, which generally requires the use of toxic gases such as BF.sub.3 and PF.sub.5. Not only is this process potentially hazardous to the environment, it also creates substantial damage in the lattice of the semiconductor material. In order to remove the damage created by the implanted ions, the semiconductor material often has to undergo a long annealing cycle at high temperatures generally in excess of 600.degree. C. Such an annealing process makes it difficult to form shallow junctions and highly doped regions because of diffusion. Worse yet, certain types of dopants such as boron, tend to create deep junctions when implanted because of so-called "channeling effects" even in the absence of a high temperature annealing step.
In addition to the difficulty in forming shallow junctions, ion implantation is ill-suited to the fabrication of large-area displays and sensors because they are typically fabricated on glass substrates, whose structural integrity and stability deteriorate at high temperatures. Hence, it is important to develop a process which does not subject such substrates to high temperatures. Furthermore, the implantation process currently limits the size of the substrates on which devices and circuits can be built. There is very limited availability of commercial ion implantation equipment that can be used for substrates larger than ten to eleven inches in size. Therefore, in order to achieve shallow junctions and high doping levels in TFTs, extensive efforts have been expended to develop a low temperature doping process of at least below 600.degree. C. by using lasers.
One approach is generally known as gas immersion laser doping ("GILD"). An example of this approach is described in "Ultra-Shallow High-Concentration Boron Profiles for CMOS Processing," IEEE Electron Device Letters, vol. EDL-6, No. 6, June 1985. Under this approach, a semiconductor sample is placed in a reaction chamber into which dopants in their gaseous form such as BF.sub.3 and PF.sub.5 are introduced. Then, a pulsed excimer laser is used to irradiate the sample. The energy of the laser breaks the gas molecules and melts a thin layer of the semiconductor materials. The molecules that have sufficient kinetic energy are then absorbed by the molten semiconductor. Thus, the doping efficiency of this method depends upon the amount of dopants being absorbed by the molten semiconductor materials.
Under this approach, the substrate of the sample stays at low temperatures because each laser pulse lasts for only about 30 to 50 ns, which is only sufficient to melt approximately a few monolayers of materials. Because of the short duration, very shallow junctions can be achieved. However, since the incorporation of the dopants is limited by the equilibrium surface absorption rate at a given temperature, it is very difficult to achieve high doping levels. In order to increase the doping level, the sample needs to be irradiated by multiple pulses, which would adversely impact the throughput of this process. In other words, it is difficult for such a process to achieve high doping.
Another approach is to use a solid source such as one described in "In Situ Crystallization and Doping of a-Si Film by Means of Spin-On Glass" MRS Symposium Proceedings, vol 345, p. 59-64, 1994. Under this approach, a film transparent to lasers such as phosphorus-doped spin-on-glass ("SOG") is first spun onto the sample. When the laser irradiates the sample with the SOG, the sample is heated up to an adequately high temperature so that the dopants in the SOG can diffuse into the sample. However, since the SOG film is transparent, no absorption of laser energy by the SOG itself occurs. The approach is limited by the solid solubility limit of the dopants in the material, which again results in low doping levels. Besides low doping efficiency, another disadvantage is the difficulty associated with removing the solid doping source on the semiconductor sample. Often, the laser alters the interface between the doping source and the underlying material, damaging the surface of the underlying material when the doping source is removed.
Recently, an approach which can produce relatively high doping efficiency using lasers was set forth in "Low Temperature Fabrication of Poly-Silicon TFT's Using In-Situ Chemically Cleaning Method," Material Research Society Symposium, v. 283, p0. 629-634 (1993). Under this approach, a doped amorphous silicon layer, which is not transparent to lasers, is deposited by a method known as plasma enhanced chemical vapor deposition ("PECVD"). A laser is then used to melt and recrystallize the doped amorphous silicon film, resulting in relatively shallow and highly doped regions. However, this process does not resolve the problem associated with the subsequent removal of the deposited material. It is very difficult to selectively remove the doped amorphous silicon layer, which typically responds to etchants in a manner which is similar to that of the underlying semiconductor material.

Proximity laser doping technique for electronic materials


An apparatus for forming an image on a recording sheet having low toner pile height is disclosed. A latent image is formed on an imaging member. A developer unit develops the latent image with a less than monolayer of toner particles on the imaging member. The developed image is transferred to a compliant intermediate member whereupon a filming station spreads the toner particles to form a film layer. The station includes a heater for heating the less than monolayer of toner particles to a temperature sufficient to cause the toner particles present on the intermediate member to soften; and a roller for spreading the less than a monolayer of toner particles to generate the thin film layer. The above process is repeated for subsequent colored toners to produce a multi film layer color image. Thereafter, the multi film layer color image is transferred from the intermediate member onto a recording sheet.

A typical electrostatographic printing machine (such as a photocopier, laser printer, facsimile machine or the like) employs an imaging member that is exposed to an image to be printed. Exposure of the imaging member records an electrostatic latent image on it corresponding to the informational areas contained within the image to be printed. The latent image is developed by bringing a developer material into contact therewith. The developed image recorded on the photoconductive member is transferred to a support material such as paper either directly or via an intermediate transport member. The developed image on the support material is generally subjected to heat and/or pressure to permanently fuse it thereto.
Two types of developer materials are typically employed in electrostatographic printing machines. One type of developer material is known as a dry developer material and comprises toner particles or carrier granules having toner particles adhering triboelectrically thereto. Another type of developer material is a liquid developer material comprising a liquid carrier or dispersant having toner particles dispersed therein.
Development with liquid developers in full color imaging processes has many advantages, such as a texturally attractive print because there is substantially no toner height build-up, whereas full color images developed with dry toners often exhibit height build-up of the image where color areas overlap. Further, full color prints made with liquid developers can be made to have either a uniformly glossy or a uniformly matte finish, whereas uniformity of finish is difficult to achieve with powder toners because of variations in the toner pile height.
High toner pile height is a major document appearance problem for powder xerography. It is obvious to the customer not only as increased document thickness but also in other undesirable ways, such as paper curl. In addition to being an aesthetic dissatisfier, paper distortion due to curl and ripple increases the jam rate and complicates paper handling and document finishing. This is objectionable in any market, but especially in the production color printing market, which demands high-speed reliable operation and is accustomed to the look and feel of lithography.
Toner pile height can be reduced by reducing toner size, but the performance of current xerographic subsystem designs would be compromised for average particle sizes less than about 5 .mu.m. On the other hand, in conventional systems, if toner mass is reduced without reducing toner size, the toner does not completely cover the paper even in the Dmax areas. Incomplete paper coverage leads to significant color and image quality degradation, since even a small amount of white light from bare paper can reduce image chroma noticeably. This is particularly severe for high-chroma and/or low-lightness colors, such as deep blue.
A need exists for an electrostatic printing machine that can produce texturally attractive color prints with substantially no height build-up employing dry developers. A simple, relatively inexpensive, and accurate approach to produce color prints in such printing systems has been a goal in the design, manufacture and use of electrophotographic printers. This need has been particularly recognized in the process color and highlight color portion of electrophotography. The need to provide accurate and inexpensive color reproduction with dry developers has become more acute, as the demand for high quality, relatively inexpensive color images and the machines that produce them have increased.
The present invention obviates the problems noted above by utilizing an apparatus for forming an image on a recording sheet having low toner pile height. A latent image is formed on an imaging member. A developer unit develops the latent image with a less than monolayer of toner particles on the imaging member. The developed image is transferred to a compliant intermediate member whereupon a filming station spreads the toner particles to form a film layer from the toner particles. The station includes an optional heater for heating said monolayer of toner particles to a temperature sufficient to cause the toner particles present on the intermediate member to soften; and a heated roller for spreading said monolayer of toner particles to generate said film layer. The above process is repeated for subsequent colored toners to produce a multi-film layer color image. Thereafter, the multi-film layer of toner material is transfused from said intermediate member onto a recording sheet such as paper.

Apparatus and method for forming a toner image with low toner pile height


A PTC circuit protection device to protect electronic devices against excessive temperatures and electrical currents. The device comprises a polymeric resistor element, a first electrode, and a second electrode. The polymeric resistor element changes resistance in response to temperature changes. The resistor element has an upper surface and a lower surface. The first electrode is in electrical contact with both the upper surface and the lower surface. The second electrode is in electrical contact with both the upper surface and the lower surface. The circuit protection device has a first effective area of resistance and a second effective area of resistance that is electrically in parallel with the first effective area.

A circuit protector having a positive temperature coefficient of resistance is commonly referred to as a PTC device and the specific material that provides the resistance characteristic is commonly referred to as a PTC material or a PTC resistor element. PTC devices are commonly employed in a variety of different electronic devices, such as electric motors, to protect the device against over current and/or excessive temperature conditions.
The PTC device is typically positioned within the current path that supplies power to the protected device such that the current must pass through the resistor element of the PTC device before the current reaches the protected device. Under normal operating temperatures and currents, the resistor element exhibits a relatively low resistance to current and permits the substantially unimpeded flow of current to the protected device. When the current or the environmental temperatures become excessive, the resistivity of the PTC device increases to at least substantially restrict the amount of current delivered to the protected device to prevent the protected device from being damaged.
The resistor element is typically a polymeric resistor element that has a homogeneous mixture of polyolefin material and conductive carbon particles. At normal operating temperatures and currents, the resistor element has a crystalline structure, which provides a low-resistance conductive path device. When excessive temperatures and/or currents are encountered, the resistor element undergoes a phase change (switching action) to an amorphous (non-crystalline) structure and an expansion of the polyolefin. The phase change inhibits conductivity by separating the carbon black particles and results in an increased resistance. The phase change occurs in a very narrow temperature band, resulting in a rapid increase in the resistance of several orders of magnitude. The high resistance state limits current flow to the protected device and protects the device from being damaged by excessive current and/or temperatures. After the excessive temperature and/or current ceases, the resistor element returns to its low-resistance state. The resistor element can be brought to its phase change temperature by self-induced I2R heating or by exposure to an elevated temperature in the surrounding environment.
Even when the PTC device is operating in its low-resistance state under normal operating conditions, the PTC device inhibits, to some extent, current flow to the protected device. Therefore, due to the presence of the PTC device, additional current is required to power the protected device than would otherwise be required in the absence of the PTC device. To conserve energy, it is desirable that the resistance of the resistor element be as low as possible under normal operating currents and temperatures. While the resistivity of conventional PTC devices at standard operating conditions is low enough to provide PTC devices that are suitable for their intended purposes, there is a need for a PTC device having an even lower resistance at normal operating conditions to decrease the amount of current needed to operate the protected device and to therefore conserve energy.
Under normal operating conditions, the overall resistance (Ω) of the PTC device is a function of the resistor element's thickness (t), resistor element area of effective resistance (A) (its length (l) multiplied by its width (w)) and resistivity (ρ), which is a property inherent to the composition of the particular resistor element. Specifically, under normal operating conditions the overall resistance of the PTC device can be calculated by the following equation:Ω=(t/A)(ρ), where A=w*l.The resistor element area of effective resistance is the portion of the resistor element through which current actually passes and is, therefore, the portion of the resistor element that actually provides a resistance to the current. The greater the area of effective resistance (A), the lower the overall resistance (Ω) of the PTC device. Further, it is a well established property that resistors electrically connected in parallel have a lower resistance than resistors connected in series. Therefore, PTC devices having multiple resistor elements in parallel have a lower resistance under normal operating conditions than PTC devices having multiple resistor elements in series.
While PTC devices having a decreased resistance under normal operating conditions can be obtained by increasing the resistor element's area of effective resistance, there exists a competing need to keep the overall dimensions of the PTC device as small as possible to enable the PTC device to be used in applications where space is at a premium. The present invention fulfills the need for a PTC device having a decreased resistance under normal operating conditions by providing PTC devices that each have multiple resistor elements in parallel and an enlarged area of effective resistance as compared to conventional PTC devices. A plurality of the improved PTC devices can be provided together in parallel in a PTC assembly that has a resistance under normal operating conditions that is lower than the resistance of any of the improved PTC devices alone.
An understanding of conventional PTC devices allows one to better appreciate the features of the current invention. FIG. 1 illustrates an exemplary PTC device at 10. The conventional PTC device 10 generally includes a polymeric PTC resistor element 12, a first electrode 14, and a second electrode 16. The resistor element 12 generally includes an upper surface 18, a lower surface 20, a first end 22, and a second end 24. The first electrode 14 has a first portion 26 and a second portion 28. The second electrode 16 generally includes a first portion 30 and a second portion 32. The first portions 26 and 30 and the second portions 28 and 32 are positioned on opposite sides of the resistor element 12.
The first portion 26 of the first electrode 14 is positioned on or closely adjacent to the upper surface 18 of the resistor element 12 and the second portion 28 of the first electrode 14 is positioned on or closely adjacent to the lower surface 20 of the first electrode 14. The first portion 26 and the second portion 28 are electrically connected by a first side electrode 34. The first side electrode 34 spans the thickness of the resistor element 12 at the first end 22.
The first portion 30 of the second electrode 16 is positioned on or closely adjacent to the upper surface 18 of the resistor element 12 and the second portion 32 of the second electrode 16 is positioned on or closely adjacent to the lower surface 20 of the resistor element 12. The first portion 30 and the second portion 32 are electrically connected by a second side electrode 36. The second side electrode 36 spans the width of the resistor element 12 at the second end 24.
The first electrode 14 is positioned such that the first portion 26 opposes the second portion 28 on the opposite side of the PTC element 12. Similarly, the second portion 32 of the second electrode 16 is positioned such that it opposes the first portion 30. The first portion 26 of the first electrode 14 and the second portion 32 of the second electrode 16 extend beyond the second portion 28 and the first portion 30 respectively toward the center of the device 10 and overlap at the center of the device 10. The first electrode 14 and the second electrode 16 are separated by skive marks or gaps 37A and 37B.
With additional reference to FIGS. 2 and 3, when electrical contact is made at any point on the first electrode 14 and the second electrode 16 and electrical current is supplied to the electrodes 14,16, current passes between the electrodes 14,16 through the resistor element 12 in the region ER where the electrodes 12,14 overlap. The region ER is the area of effective resistance of the PTC device 10. As illustrated, the area of effective resistance ER of the resistor element 12 is much smaller than the overall area of the element 12 and the resistance of the device 10 at normal operating conditions is greater than it would be if the area of effective resistance ER of the element 12 was increased. Further, as illustrated in FIG. 3 where the area of effective resistance ER is illustrated in a circuit diagram, the PTC device 10 only has a single area of effective resistance ER, thus causing the PTC device 10 to have a greater resistance under normal operating conditions than it would otherwise have if the resistor element 12 was divided into multiple areas of effective resistance electrically in parallel.
Thus, there is a need for an improved PTC device that exhibits a reduced resistance under normal operating conditions as compared to the conventional PTC devices, such as the PTC device 10.

PTC circuit protector having parallel areas of effective resistance


Disclosed is a system for replicating data. The system may comprise a plurality of nodes preferably organized in groups with one of the nodes acting as a coordinator node. The nodes are configured to receive write requests from an external server and to apply these write requests to a data storage source of the data storage system. The write requests typically belong to a batch of independent write actions identified by a batch sequence number. Each node stores the write request in non-volatile memory with the coordinator node monitoring which batches are secured in their entirety in non-volatile memory. The coordinator node authorizes all other nodes to sequentially replicate the write requests in their non-volatile memory to the data storage source for all writes up to the highest batch sequence number for which all writes have been secured in non-volatile memory.

In data storage systems, asynchronous replication may be implemented by identifying groups of independent writes submitted from external server systems at a production site, forming batches of these writes, and applying these batches in sequential order at a disaster recovery (DR) site. Writes are considered independent if they are submitted to the storage system within the same time frame, i.e. none of these writes is completed back to the server before another write in the batch is submitted to the storage system. By applying batches serially, data consistency of the volumes at the DR site is maintained at all times.
For performance reasons, on a distributed storage system the set of independent writes in a batch must be pessimistic, i.e. fewer writes are considered independent than may be the case. This means that each batch may contain a small number of writes only.
At the DR site, which may also be a distributed storage system, the writes in a batch are typically applied to many storage volumes across the storage system. Consequently, the serial processing of batches must be coordinated across the entire distributed storage system, through messaging between the different elements of the distributed system to ensure data consistency. The batches may be identified using some form of serial number, as for instance is disclosed in U.S. Pat. No. 8,468,313 B2.
The throughput of such asynchronous replication is therefore limited by the messaging within the DR site; the number of batches per second that can be processed is limited by the number of batch synchronization messages that can be sent and received at the same time. The performance of the asynchronous replication is also negatively affected by any delay to any write the DR site is processing as part of a batch, as the serialization of batches ensures that the next batch cannot be started until all the writes from the batch in progress are complete. Delays to writes can happen for many reasons: when a multitasking operating system is used within the storage system, writes may be delayed for hundreds of milliseconds just from task preemption.
Such a design thus limits maximum throughput. As there is little scope to catch up, such asynchronous replication designs usually become unstable following any delays to any of the writes.
One approach to solve this problem is to group many batches together and apply them atomically. This may be done using an incremental point-in-time copy. Such a process requires additional storage, and tight integration between the replication, point-in-time copy, and any caching features. It also requires coordination of triggering many point-in-time copies across the whole distributed DR storage system. This means that there will be significant periods during which no further replication writes may be processed because the point-in-time copies are starting. These new replication writes then have to be absorbed somewhere in additional storage, or else new writes from the external server systems at the production site will have to be delayed. It is clear that this is far from ideal from a performance perspective.


Systems and methods are described for utilizing acceleration event signatures. One method for utilizing acceleration event signatures in an electronic device comprises receiving, by the electronic device, one or more acceleration events. The method further comprises determining whether the received one or more acceleration events correspond to one or more predefined signature definitions and invoking one or more functions based on the one or more acceleration events.

Over the years, mobile devices such as smartphones have become widespread. With the rapid development in communication technology, smartphones have become an integral part of many people's lives given the portability, the convenient access to the Internet, and the growing number of applications available on smartphones. Today, individuals can perform a wide range of functions such as shopping, social networking, etc. via mobile devices. To operate such devices, physical hardware keys are commonly used to control such functions as audio volume control, display sleep/wake control, ringer-off mode, and so on. However, physical hardware keys and the surrounding circuitry can weaken in mechanical tactility or electrical conductivity over time, thereby causing performance degradation.
In addition, physical keys may make it more difficult to seal or water-proof a device. Thus, electromechanical functions can present reliability concerns. Furthermore, the location of physical hardware keys may act as a point of entry for electrostatic discharge, which can damage mobile devices. Finally, physical hardware keys and the surrounding circuitry often use a significant portion of the highly sought-after circuitry real estate around the edge of a circuit board or device where antennas, acoustic orifices, and/or connectors compete for access to external interfaces. The industrial design of a product must also accommodate provisions for the key buttons, which may affect the overall design theme.

Systems and methods for utilizing acceleration event signatures


A thoracentesis sheath catheter assembly includes a catheter connected to a valve body. The valve body is provided with a throughbore coaxial to the catheter for receiving a thoracentesis needle therethrough and a drainage bore in fluid communication with the first throughbore. The valve body is constructed as a first cylindrical portion which is connected to the catheter and a second cylindrical portion of larger inner diameter which is joined to the first cylindrical portion by a tapered inner wall. The second cylindrical portion contains a valve comprising a blocking ball and a spring biased plunger having a throughbore coaxial to the catheter, and is closed with a cap having a central hole and/or a gasket for sealingly receiving the thoracentesis needle. A thoracentesis needle extends through the hole of the cap, the gasket, the plunger, the first cylindrical portion and into and through the catheter. With the thoracentesis needle in place, communication between the throughbore and the drainage bore is blocked and a flow path is established through the needle. When the needle is removed, the throughbore is automatically obstructed by movement of the ball by the plunger along the tapered inner wall. However, a second fluid path is automatically established from the throughbore to the drainage bore.

The present invention generally relates to medical instruments. More particularly, the present invention relates thoracentesis needle devices which are used in the removal of fluid from the pleural cavity and which prevent air entry into the pleural cavity during use. Specifically, the invention relates to a sheath catheter assembly for a thoracentesis needle.
The thoracentesis procedure involves incising through the chest wall, and inserting a tube or catheter through the chest wall and into the pleural cavity. By providing a negative pressure at the proximal end of the catheter, intrathoracic fluid such as blood, puss, air, and other secretions are removed from the pleural cavity. While removal of the intrathoracic fluid is desirable, at the same time it is imperative for a negative pressure to be maintained in the pleural cavity in order to permit the lungs to remain expanded such that breathing can continue. In order to maintain a negative pressure in the pleural cavity, care must be taken to avoid communication between the pleural cavity and atmospheric pressure, as a passage of air from outside the body into the pleural cavity can collapse the lung; a medical condition known as pneumothorax.
A common manner of conducting a thoracentesis procedure is to make a chest wall incision using a needle. In introducing the needle into the pleural cavity, care must be taken to avoid pushing the needle too far and puncturing the lung, as air from the lung space could escape into the pleural cavity and result in a lung collapse. In such cases it is actually possible to produce a pressure within the pleural cavity which is greater than atmospheric pressure, and cardiac compromise is a possible consequence.
A thoracentesis device which purportedly reduces possibility of lung puncture and reduces pneumothorax due to entry of air into the pleural cavity is proposed in U.S. Pat. No. 4,447,235 to Clarke. The proposed device includes a needle having a drainage opening which extends through a catheter and through an elongated conduit connected to the catheter. The elongated conduit is provided with an elastomeric seal and a manual valve. The elastomeric seal, which is punctured by the needle when the needle ia inserted through the elongated conduit and catheter, prevents air leakage into the pleural cavity by sealing around the needle and resealing when the needle is removed. The manual valve, when moved, permits the elongate conduit to open to a side conduit when the needle is removed, thereby permitting long term drainage of the pleural cavity. In the Clarke patent, the removal of the needle is what reduces the possibility of lung puncture.
In addition to the device proposed in the Clarke patent, devices and procedures are set forth in U.S. Pat. Nos. 4,784,156, 4,832,044, 4,840,184, and 4,844,087 to Garg. In the Garg patents, a manual in-line valve is provided, and upon retraction of the needle past the valve, the valve is turned such that entry of air into the pleural cavity is prevented.
While the prior art patents represent advances in the art, it should be appreciated that with the prior art devices, it is still relatively easy for even a skilled surgeon to puncture the lung by pushing the needle just slightly too far into the pleural cavity. In fact, even if the needle is in the pleural cavity for a short period of time, should the patient move or cough, or even take a deep breath, it is possible for the needle to puncture the lung. In addition, with the manual valve structures of the prior art, should the attending surgeon forget to properly move the valve into the desired positions at certain times, undesirable results may be obtained.
Also long known in the art are needles called "Veress" or "Veress-type" needles. Veress needles are needles with an outer needle having a sharp distal end and an inner probe which extends through the outer needle with the probe having a blunt distal end. In Veress needles, the inner probe is biased to force the blunt distal end of the probe beyond the sharp distal end of the outer needle. However, when the blunt distal end of the probe encounters dense material, the probe is forced backward and the sharp end of the needle is presented so that it can puncture the dense material. Veress needles are used in the art almost exclusively for insufflation (injection of carbon dioxide) of the abdomen during laparoscopy procedures, and Veress needles with manual shut-off valves are known in the art. Veress needles have also been suggested for use in a thoracentesis procedure (See, Jenkins, Jr. Douglas, et al., "Veress Needle in the Pleural Space", Southern Medical Journal: Vol. 76, No. 11, pp. 1383-1395 (Nov. 1983)), although the techniques suggested therein in a test study have not gained popularity over the several years since they were reported and are not today used in common practice. Regardless of use, the Veress needle assemblies of the art have not before been modified for particular use in conjunction with withdrawal of fluid, and in particular withdrawal of fluid from the pleural cavity. Indeed, the Veress needle assemblies of the art have not been used with automatic check valves.
Parent application Ser. No. 07/860,447, discloses and claims a thoracentesis needle assembly which utilizes a Veress-type needle arrangement to overcome lung puncture problems as well as an automatic valve to prevent pneumothorax. In addition, the disclosed needle assembly may be used with a catheter such as the catheter disclosed by Clarke in U.S. Pat. No. 4,447,235. The catheter disclosed by Clarke, like the cannulae disclosed by Garg in U.S. Pat. Nos. 4,784,156, 4,832,044, 4,840,184, and 4,844,087, provides a manual valve in line with the needle assembly, and with a hollow cylindrical stopcock rotatably fitted with an external lever. Moving the external lever in one direction allows the thoracentesis needle to pass into the catheter, and moving the external lever in the other direction after the thoracentesis needle is removed prevents air from entering the catheter and directs fluid flow to a drainage attachment or the like. The chief disadvantages of the Clarke arrangement are that a valve which can be subject to clogging is used in the flow line, and that the in-line valve must be of exact design to permit needle insertion. Moreover, the attending surgeon must remember to set the valve to the correct position at the correct time. When the needle is inserted in the catheter, the valve must be placed in one position wherein the needle passes through the valve. After the needle is withdrawn from the catheter, the valve must be manually turned to a second position to redirect fluid flow from the catheter and block the needle passage. While Clarke provides an elastomeric seal in addition to the manual valve to prevent air from entering the catheter after the needle is withdrawn, this seal is merely a piece of elastomeric material which is pierced when the needle is inserted. Theoretically, when the needle is withdrawn, the elastomeric material will contract and close the opening which was made when the needle pierced it. While this solution sounds reasonable, it assumes that a needle of very small diameter is used. In practice, however, if a Veress-type needle is used, a piece of the elastomeric seal can be cut off by the needle and embedded inside the hollow of the needle. This presents two problems: first, a piece of elastomeric material will be delivered into the pleural cavity, and second, the resealing of the elastomeric seal is severely compromised since a piece of it is now missing.


A golf putter head having a generally disk like shape with top and bottom surfaces substantially circular in shape, a rounded rear surface and a front surface being flattened thereby providing a face for striking a golf ball. The width of this face being approximately one third the width of the putter head. The putter head having a center of gravity positioned behind the face of the putter head at a distance of approximately one half the putter head length and an alignment stripe on its top surface. The unique shape of this putter head, alignment stripe, size and position of the putter head face, and location of the putter head center of gravity allows the putter head to: (1) improve and simplify the pre-putt alignment procedure, (2) consistently impact the golf ball on "sweet spot" of the putter head face thereby eliminating weak and ineffective putts, (3) have a shorter more controlled putter head backswing with a resulting high percentage of positive contact with the golf ball, and (4) eliminate putter head twist when impacting the golf ball thereby reducing misdirected putts.

1. Field of Invention
This invention relates to an improved golf putter head.
2. Description of Prior Art
Putting is often considered the most difficult part of the game of golf. When putting, the golf ball must be hit with a precise amount of force and in a precise direction. If not, the golf ball will either nor reach the cup (i.e. hole) or it will miss the cup on one side or the other. Various attempts have been made to design putters and in particular putter heads which will impart the precise amount of force and direction to a golf ball to successfully complete a putt. Applicant is aware of a number of U.S. patents which disclose various structural improvements to golf club putters and in particular golf club putter heads as follows:
______________________________________ 4,592,552 Garber 4,747,599 Antonious 5,246,231 Antonious 5,458,332 Fisher 5,464,215 Koehler ______________________________________
A review of the above patents as well as other putter patents up to the present time will reveal that most putter head designs are variations of either a blade type putter head or a mallet type putter head and that both these types of putter heads are affected by parameters which can cause mis-hit and misdirected putts. Among these parameters are the width of the putter head face (Fw), the length of the putter head (H1), and the location of the putter head center of gravity (C.G.).
The face or front of the putter head is that portion of the head which actually makes direct contact with the golf ball. Most blade type and mallet type putter heads employ a face that is usually as wide or almost as wide as the widest portion of the head. Typically, blade type putter heads have face widths greater than 4 inches while mallet type heads have face widths greater than 3 inches. The length of the putter head is defined as the distance from the face to the back the putter head. The width of the putter head face and the length of the putter head are factors in successful putting in that they affect (1) the pre-putt alignment of the the putter head, (2) the impacting of the golf ball on the "sweet spot " of the putter face, and (3) the location of the putter head center of gravity.
Pre-putt alignment of a blade or mallet type putter head is normally accomplished by determining a line of sight to the cup and and then positioning the putter head behind the golf ball on that line of sight with the putter head face perpendicular to the line of sight. If the face of the putter head is not perpendicular to the line of sight to the cup when the putter head impacts the ball, misdirection of the putt will occur. As the length of the putt increases, even a small misalignment (i.e. a few degrees off perpendicular) will result in a missed putt. The alignment procedure could be simplified and improved by reducing putter head face width (Fw) so as to allow only a small facial area to impact the golf ball, increasing putter head length (H1), and putting an alignment stripe with dimensions (Fw.times.H1) on the top of the putter head These changes would eliminate the need for positioning the putter head face perpendicular to the line of sight during pre-putt alignment. Alignment would consist only of placing the putter head face behind the golf ball with the alignment stripe positioned on the line of sight to the cup.
Impacting the golf ball on the sweet spot of the putter face involves determining the location of this spot and then consistently hitting the ball there. The sweet spot can be defined as a small area (typically having a width no greater than one half inch) on the face of a putter head that can impact a golf ball with the required force utilizing the shortest possible putter stroke to successfully complete a putt. The sweet spot is normally located such that a vertical middle plane will bisect the sweet spot, the putter head face, and pass through the putter head center of gravity. For example, the sweet spot on a blade type putter head face four and one half inches wide would normally be centered on the putter head face two and a quarter inches from either end of the blade. Error in the form of weak and ineffectual putts is introduced when the golf ball does not impact the sweet spot, and this error becomes greater as the distance between the sweet spot and the point of impact increases. Also, impacting the golf ball at or near the end of a mallet or blade type putter head can cause putter head twist resulting in misdirected putts. Reducing putter head face width to a fraction of the putter head width (for example one third) and positioning the face front and center on the putter head would minimize these problems.
The location of the center of gravity of the putter head is also a factor in successful putting in that increasing the distance between the center of gravity and the face of the putter head allows the golfer to take a shorter more controlled backswing of the putter head resulting in a higher percentage of positive contact with the golf ball. For a putter head of uniform density, this distance will increase as the length of the putter head is increased.