A system and method for increasing the speed of blood and the wall shear stress in a peripheral artery or peripheral vein to a sufficient level and for a sufficient period of time to result in a persistent increase in the overall diameter and lumen diameter of the artery or vein is provided. The method includes systems and methods to effect the movement of blood at the desired rate and in the desired direction. The movement of blood is monitored and adjusted, as necessary, to maintain the desired blood speed and wall shear stress in the peripheral artery or vein in order to optimize the rate and extent of persistent diameter increase of the peripheral artery or peripheral vein.

Many patients with chronic kidney disease (CKD) eventually progress to end-stage renal disease (ESRD) and need renal replacement therapy to remove fluid and waste products from their bodies and sustain their lives. Most patients with ESRD needing renal replacement therapy receive hemodialysis, where blood is removed from the circulatory system, cleansed in a hemodialysis machine and then returned to the circulatory system. To facilitate hemodialysis, surgeons create discrete "vascular access sites" that can be used to remove and return blood rapidly from ESRD patients. While major advances have been made in hemodialysis machines themselves and other parts of the hemodialysis process, the creation of durable and reliable vascular access sites has seen only modest improvement and remains the Achilles' heel of renal replacement therapy. Failure to provide suitable vascular sites often results in sickness and death for ESRD patients and places a large burden on health care providers, payers, and public assistance programs worldwide.
Vascular access sites for hemodialysis generally come in three forms: arteriovenous fistulas (AVF), arteriovenous grafts (AVG), and catheters. Each type of access site is susceptible to high rates of failure and complications, as described below.
An AVF is constructed surgically by creating a direct connection between an artery and a vein. A functional AVF created at the wrist between the radial artery and the brachial vein is the longest-lasting and most desirable form of hemodialysis access, with a mean patency of about 3 years. The vein leading away from the connection is called the "outflow" vein. Persistent increases in the overall diameter and lumen diameter of the outflow vein are critical components for an AVF to "mature" and become usable. It is widely believed that the rapid flow of blood in the outflow vein created by the AVF and the WSS exerted on the endothelium of the vein is a major factor in bringing about persistent increases in the overall diameter and lumen diameter of the outflow vein. Unfortunately, approximately 80% of ESRD patients are not eligible for an AVF placement at the wrist, usually due to inadequate vein or artery diameters. For eligible patients where AVF placement is attempted, the site may not be usable without further intervention in about 50%-60% of cases, a problem known as "maturation failure." Small blood vessel diameter, especially small vein diameter, has been identified as a factor in AVF maturation failure. The rapid appearance of aggressive vein wall scarring known as "intimal hyperplasia" has also been identified as an important factor in AVF maturation failure. Some investigators have postulated that areas of relatively rapid or turbulent blood flow in the vein (with resultant high local WSS) are a major factor in causing vein wall scarring, while other investigators propose that this scarring is caused by areas of relatively slower or oscillating blood flow and relatively low or oscillating WSS. In response, attempts have been made to modulate flow patterns in AVF outflow veins in order to minimize AVF failure rates. Still other investigators have postulated that cyclic stretching of the vein caused by the entry of pulsatile arterial blood may also play a role in the stimulation of intimal hyperplasia and outflow vein obstruction in AVF. At the current time, no method exists which preserves the positive effects of elevated blood speed and WSS that cause persistent increases in the overall diameter and lumen diameter or arteries and veins, while eliminating the negative effects of vein wall scarring and obstruction. Not surprisingly, a patient newly diagnosed with ESRD and in need of hemodialysis has only a 50% chance of having a functional AVF six months after starting hemodialysis. Those patients without a functional AVF must undergo hemodialysis with more costly forms of vascular access and are at a greater risk of complications, sickness, and death.
A second type of vascular access site for hemodialysis is an arteriovenous graft (AVG). An AVG is constructed by placing a segment of synthetic conduit between an artery and vein. Typically, an AVG is constructed in the arm or the leg. A portion of the synthetic conduit is placed immediately under the skin and used for needle access. More patients are eligible for AVGs than AVFs, since veins not visible on the skin surface can be used for outflow, and the rate of early failure is much lower than that for AVFs. Unfortunately, AVGs have a mean primary patency of only about 4-6 months, because aggressive intimal hyperplasia and scarring develops rapidly in the wall of the outflow vein near the connection with the synthetic conduit, thus leading to stenosis and thrombosis. Similar to AVF failure, some investigators have postulated that the rapid and turbulent flow of blood in the outflow vein created by the AVG causes intimal hyperplasia and scarring in the wall of the outflow vein, while other investigators have proposed that this scarring is caused by areas of relatively slower or oscillating blood flow and relatively low or oscillating WSS. Still other investigators have postulated that cyclic stretching of the vein caused by the entry of pulsatile arterial blood into the outflow vein may also play a role in the formation of intimal hyperplasia and outflow vein obstruction in an AVG. Although AVGs are less desirable than AVFs, about 25% of patients dialyze with an AVG, mostly because they are not eligible to receive an AVF.
A third type of vascular access site is a catheter. Patients who are not able to get hemodialysis through an AVF or AVG can have a large catheter inserted in the neck, chest, or leg in order to receive hemodialysis. These catheters often become infected, thus placing the patient at high risk for sepsis and death. Patients with catheter sepsis usually require hospitalization, removal of the catheter, insertion of a temporary catheter, treatment with IV antibiotics, and then placement of a new catheter or other type of access site when the infection has cleared. Catheters are also susceptible to obstruction by thrombus and fibrin build-up around the tip. Hemodialysis catheters have a mean patency of about 6 months and are generally the least desirable form of hemodialysis access. Although catheters are less desirable than AVFs and AVGs, about 20% of patients dialyze with a catheter, mostly because they have not been able to receive a functional AVF or AVG, or are not eligible to receive an AVF or AVG.
The problem of hemodialysis access site failure has received more attention recently as the number of ESRD patients undergoing routine hemodialysis has increased worldwide. In 2004, the Centers for Medicare & Medicaid Services (CMS) announced a "Fistula First" initiative to increase the use of AVFs in providing hemodialysis access for patients with end-stage renal failure. This major initiative is a response to published Medicare data showing that patients who dialyze with an AVF have reduced morbidity and mortality compared to patients with an AVG or a catheter. Costs associated with AVF patients are substantially lower than the costs associated with AVG patients in the first year of dialysis, and in subsequent years. The cost savings of a dialyzing with an AVF are even greater when compared to dialyzing with a catheter.
To be eligible for an AVF, patients generally need to have a peripheral vein with an overall diameter of at least 2.5 mm and a peripheral artery with an overall diameter of at least 2.0 mm, with the understanding that different vascular surgeons will set different threshold levels. To be eligible for an AVG, patients generally need to have a peripheral vein with an overall diameter of at least 4 mm and a peripheral artery with an overall diameter of at least 3.0 mm, with the understanding that different vascular surgeons will set different threshold levels. Currently, there is no method for persistently increasing the overall diameter and lumen diameter of peripheral veins and arteries in ESRD patients who have inadequate initial vein or artery size prior to the creation of an AVF or AVG. Consequently, patients with veins or arteries that are too small to attempt an AVF or AVG must use less desirable forms of vascular access such as catheters. Similarly, there is currently no approved method for the treatment of AVF maturation failure, which falls disproportionately on patients with small vein and artery diameters, such as women and minorities. Thus, there is a desire for systems and methods for enlarging the overall diameter and lumen diameter of a vein or artery prior to the creation of AVF or AVG. A recent study demonstrated that ESRD patients who were forced to use less desirable forms of vascular access such as catheters had a substantially higher risk of becoming sick or dying when compared with patients who were able to use an AVF or AVG for hemodialysis.
There is also a need to persistently increase the vein or artery diameter for patients with atherosclerotic blockages of peripheral or coronary arteries in need of bypass grafting. Patients with peripheral artery disease (PAD), who have an obstruction to blood flow in the arteries of the legs, often suffer from claudication, skin ulceration, and tissue ischemia. Many of these patients may eventually require amputation of portions of the affected limb. In some PAD patients the obstruction can be relieved to an adequate degree by balloon angioplasty or the implantation of a vascular stent. In other patients, however, the obstruction is too severe for these types of minimally invasive therapies. Therefore, surgeons will often create bypass grafts that divert blood around the obstructed arteries and restore adequate blood flow to the affected extremity. However, many patients in need of a peripheral bypass graft cannot use their own veins as bypass conduits due to inadequate vein or artery diameter and are forced to use synthetic conduits made of materials such as expanded polytetrafluoroethylene (ePTFE, e.g. Gore-Tex) or polyethylene terephthalate (PET, e.g. Dacron). Studies have shown that using a patient's own veins as bypass conduits results in better long term patency than using synthetic bypass conduits made from materials such as PTFE, ePTFE, or Dacron. The use of a synthetic bypass conduit increases the risk of stenosis in the artery at the distal end of the graft and thrombosis of the entire conduit, thereby resulting in bypass graft failure and a recurrence or worsening of symptoms. Thus, there is a desire for systems and methods for increasing the overall diameter and lumen diameter of veins prior to the creation of bypass grafts for patients who are ineligible to use their own veins for the creation of a bypass graft due to inadequate vein diameter.
Patients with coronary artery disease (CAD) who have an obstruction to blood flow to their heart often suffer from chest pain, myocardial ischemia, and myocardial infarct and many of these patients eventually die from the disease. In some of these patients, the obstruction can be relieved to an adequate degree by balloon angioplasty or the implantation of a vascular stent. In many patients, however, the obstruction is too severe for these types of minimally invasive therapies. Therefore, surgeons will often create a bypass graft that diverts blood around the obstructed arteries and restores adequate blood flow to the affected regions of the heart, with the internal mammary arteries and the radial arteries as preferred conduits. However, some patients in need of coronary bypass grafts cannot use internal mammary or radial arteries due to inadequate artery diameter and must use peripheral veins. Studies have shown that using a patient's internal mammary and radial arteries as bypass conduits results in better long-term patency than using peripheral vein segments. The use of peripheral veins as bypass grafts increases the risk of stenosis in the graft and thrombosis of the entire conduit, resulting in bypass graft failure and a recurrence or worsening of symptoms. Thus, there is a desire for systems and methods for increasing the overall diameter and lumen diameter of arteries prior to the creation of coronary bypass grafts for patients who are ineligible to use their own arteries for the creation of a bypass graft due to inadequate artery diameter. Furthermore, systems and methods for increasing the overall diameter and lumen diameter of veins prior to the creation of coronary bypass grafts are also desired for patients with small peripheral vein diameters.

System and method to increase the overall diameter of veins and arteries


A method for securing data on a mobile device that supports both enterprise and personal applications. According to the method, information flows and data accesses are tracked on the device at run-time to enable access control decisions to be performed based on a policy, such as an enterprise privacy policy that has been distributed to the device from an enterprise server. The policy may be updated by events at the device as well as at the enterprise server.

1. Technical Field
This disclosure relates generally to information security and, in particular, to a policy-based approach to secure enterprise data on mobile devices.
2. Background of the Related Art
The recent past has seen an enormous growth in the usage and capabilities of mobile devices, such as smartphones, tablets, and the like. Such devices comprise fast processors, large amounts of memory, gesture-based multi-touch screens, and integrated multi-media and GPS hardware chips. Many such devices use open mobile operating systems, such as Android. The ubiquity, performance and low cost of mobile devices have opened the door for creation of a large variety of mobile applications.
Enterprises are now providing their workforce with mobile devices to enable them to work from anywhere. In addition, enterprise employees also are using their personal mobile devices to connect to enterprise networks to enable them to work from remote locations. Under these scenarios, enterprises need to consider the implications of mobile devices on enterprise security and, more specifically, they need to ensure that sensitive enterprise data does not leak through these devices. This is a complex problem for which, currently, there are no adequate solutions.
Thus, for example, in a typical use scenario, an end user runs both enterprise and personal applications concurrently on a smartphone. This operating scenario presents many potential problems. Because these devices do not include on-device mechanisms for controlling resident data usage, and because users have no control over data once they authorize access by their resident applications, there is no way to protect sensitive enterprise data from arbitrary application and modifications. Further, because (from the device's perspective) all applications are assumed to be equal, there is no way to prevent information leakage between enterprise and personal applications. Indeed, this information leakage is exacerbated by open interface mobile operating systems (such as Android), which are designed to allow data sharing among applications. Further, because mobile device operating systems can be jail-broken or otherwise rooted to override existing security mechanisms and install malicious software, there is no effective way to manage the integrity of software running on the device. Indeed, because end users can download and install virtually any application without knowledge of the application's security behavior, it is very difficult to control applications (or their runtime behavior) once installed on the device.
As a result, when mobile devices support both enterprise and personal applications, there is a high likelihood that sensitive enterprise data leaks through the personal applications. In this scenario, the enterprise has no guarantee that its sensitive data will not be used by the personal application. The problem may be exacerbated if enterprise applications from multiple different enterprises are running on the device (such as where the user is a service provider for multiple such entities). In this scenario there is a further need to protect the enterprise applications from one another. Further, often there are no trust guarantees on the device, which presents the possibility that the device itself may be running rogue system software that has the potential to leak sensitive data outside the device.

This patent is subject to a terminal disclaimer.

Policy-based dynamic information flow control on mobile devices

International Business Machines Corporation


An electrified vehicle includes a global positioning system (GPS) module. The vehicle further includes a controller programmed to learn a source identification for a charging error during charge events. The controller receives location data corresponding to each charging error and utilizes the location data to determine the source identification. The source identification may be indicative of the vehicle, an offboard charger, and the operator. Errors that occur consistently at multiple locations may be assigned a higher probability of being identified as vehicle-related errors.

Electrified vehicles are configured to be charged by an offboard charger. Charging standards, such as International Standards Organization (ISO) 15118, are available that describe the interfaces between the vehicle and the offboard charger. Recent charging systems support features such as Plug and Charger (PnC), Smart Charge Scheduling, Vehicle-to-Grid (V2G) and Vehicle-to-Home (V2H) charging strategies. Implementing these new strategies has led to increased complexity in communication and coordination between the vehicle and offboard charger.

Neuro-adaptive onboard/offboard fault detector for digital charging


A cap is engaged with a container at two positions, one being a fitting section between the container and an elastic ring body provided inside of the cap to be deformable from outside of the cap, the other being an engaging section between the container and engaging pieces provided on the cap. An engaging strength of the fitting section is set stronger than an engaging strength of the engaging section. The engagement at the fitting section is released when the elastic ring body is pushed from outside of the cap and deformed.

The container with the cap is structured from a container body and a cap that is attachable and detachable to and from the container body. As the container with a cap, there is one in which the cap can be lightly taken off from the container body with a light operating force by elastic deformation of the elastic ring body. With the container disclosed in Patent literature 1 shown below, the cap forms a part of an exterior of the container and comprises a cap body having a cylindrical peripheral side wall that opens downwards, when the container body is positioned upright, and a ring body fitted inside the cap body.
The cap body has an engaging protrusion projecting inwardly from the lower end thereof. The container body is also provided with an engaging projection at an outer surface thereof. When the cap is pushed in above the container body, the protrusion of the cap body and the projection of the container body come in contact, and when the cap is pushed in further, the cap itself elastically deforms, and goes over the projection of the container body. Thus, the protrusion and projection of both parts engage, and the cap is fitted to the container body.
The ring body is provided with protrusions on the outer surface thereof which project in opposite directions from each other and are exposed to the outside from holes that penetrate from the inside to the outside of the cap body. In a state where the cap is fitted to the container body, the lower end of the ring body comes in contact with the container body, and at least one of the lower end of the ring and a contacting section of the container body with the ring body is made as an inclined surface. For example, the container body has an inclined surface above the engaging projection by gradually reducing in diameter the cylindrical shape of the container body toward the upper end, which becomes an opening of the container body. When the protrusions of the ring body which are exposed to the outer side of the cap body are pressed, the ring body is urged upwardly while coming in contact with the inclined surface. As a result, the cap body rises and the engaging protrusion of the cap body go over the engaging projection of the container body, and the engagement is released. Namely, the cap can be easily taken off.
Further, while ensuring an engaging strength in which the cap and the container do not come off accidentally, the cylindrical cap body has a discal sealing section at a ceiling portion thereof to seal an opening of the container body in order to ensure the sealing performance. As a structure of the sealing section, a tubular plug that is concentric with the disk-like ceiling section is formed by hanging down from the ceiling of the cap body, and an outer diameter of the tubular plug is made to snugly fit to an inner diameter of the opening of the container. Therefore, when the cap is fitted, the outer surface of the tubular plug contacts the inner surface of the opening of the container and seals the container. Note that, in Patent Literature 1, as the sealing section, it has been proposed to construct such that a plate-shaped packing is provided and the lower surface of the packing comes in contact with the opening rim of the container body, or a structure that a protrusion is provided to fit into a central opening of the ceiling section to be adaptable to the case where a middle plug is fitted in a central hole in the opening of the container body.


The invention relates to compounds of Formula I″

The invention relates to compounds and methods of inhibiting viral replication activity comprising contacting a SARS-CoV-2-related 3C-like ("3CL") proteinase with a therapeutically effective amount of a SARS-CoV-2-related 3C-like protease inhibitor. The invention also relates to methods of treating Coronavirus Disease 2019 ("COVID-19") in a patient by administering a therapeutically effective amount of a SARS-CoV-2-related 3C-like protease inhibitor to a patient in need thereof. The invention further relates to methods of treating COVID-19 in a patient, the method comprising administering a pharmaceutical composition comprising a therapeutically effective amount of the SARS-CoV-2-related 3C-like protease inhibitor to a patient in need thereof.
A worldwide outbreak of Coronavirus Disease 2019 ("COVID-19") has been associated with exposures originating in late 2019 in Wuhan, Hubei Province, China.
By mid-2020 the outbreak of COVID-19 has evolved into a global pandemic with millions of people having been confirmed as infected and resulting in hundreds of thousands of deaths. The causative agent for COVID-19 has been identified as a novel coronavirus which has been named Severe Acute Respiratory Syndrome Corona Virus 2 ("SARS-CoV-2"). The genome sequence of SARS-CoV-2 has been sequenced from isolates obtained from nine patients in Wuhan, China and has been found to be of the subgenus Sarbecovirus of the genus Betacoronavirus. Lu, R. et al. The Lancet, 395, 10224, 565-574; online Jan. 29, 2020. The sequence of SARS-CoV-2 was found to have 88% homology with two bat-derived SARS-like coronaviruses, bat-SL-CoVZC45 and bat-SL-CoVZXC21, which were collected in 2018 in Zhoushan, eastern China.
SARS-CoV-2 was also found to share about 79% homology with Severe Acute Respiratory Syndrome Corona Virus ("SARS-CoV"), the causative agent of the SARS outbreak in 2002-2003, and about 50% homology with Middle East Respiratory Syndrome Coronavirus ("MERS-CoV"), the causative agent of a respiratory viral outbreak originating in the Middle East in 2012. Based on a recent analysis of 103 sequenced genomes of SARS-CoV-2 it has been proposed that SARS-CoV-2 can be divided into two major types (L and S types) with the S type being ancestral and the L type having evolved from the S-type. Lu, J.; Cui, J. et al. On the origin and continuing evolution of SARS-CoV-2; National Science Review, 7(6), June 2020, 1012-1023, http://doi.org/10.1093/nsr/nwaa036. The S and L types can be clearly defined by just two tightly linked SNPs at positions 8,782 (orf1ab:T8517C, synonymous) and 28,144 (ORFS: C251T, S84L). In the 103 genomes analyzed approximately 70% were of the L-type and approximately 30% were of the S-type. It is unclear if the evolution of the L-type from the S-type occurred in humans or through a zoonotic intermediate but it appears that the L-type is more aggressive than the S-type and human interference in attempting to contain the outbreak may have shifted the relative abundance of the L and S types soon after the SARS-CoV-2 outbreak began. The discovery of the proposed S- and L- subtypes of SARS-CoV-2 raises the possibility that an individual could potentially be infected sequentially with the individual subtypes or be infected with both subtypes at the same time. In view of this evolving threat there is an acute need in the art for an effective treatment for COVID-19 and for methods of inhibiting replication of the SARS-CoV-2 coronavirus.
Recent evidence clearly shows that the newly emerged coronavirus SARS-CoV-2, the causative agent of COVID-19 (Centers for Disease Control, CDC) has acquired the ability of human-to-human transmission leading to community spread of the virus. The sequence of the SARS-CoV-2 spike protein receptor-binding domain ("RBD"), including its receptor-binding motif (RBM) that directly contacts the angiotensin-converting enzyme 2 receptor, ACE2, is similar to the RBD and RBM of SARS-CoV, strongly suggesting that SARS-CoV-2 uses ACE2 as its receptor. Wan, Y.; Shang, J.; Graham, R.; Baric, R. S.; Li, F.; Receptor recognition by the novel coronavirus from Wuhan: An analysis based on decade-long structural studies of SARS coronavirus; J. Virol. 2020; doi:10.1128/JVI.00127-20. Several critical residues in SARS-CoV-2 RBM (particularly GIn493) provide favorable interactions with human ACE2, consistent with SARS-CoV-2's capacity for human cell infection. Several other critical residues in SARS-CoV-2's RBM (particularly Asn501) are compatible with, but not ideal for, binding human ACE2, suggesting that SARS-CoV-2 uses ACE2 binding in some capacity for human-to-human transmission.
Coronavirus replication and transcription function is encoded by the so-called "replicase" gene (Ziebuhr, J., Snijder, E. J., and Gorbalenya, A. E.; Virus-encoded proteinases and proteolytic processing in the Nidovirales. J. Gen. Virol. 2000, 81, 853-879; and Fehr, A. R.; Perlman, S.; Coronaviruses: An Overview of Their Replication and Pathogenesis, Methods Mol. Biol. 2015; 1282: 1-23. doi:10.1007/978-1-4939-2438-7_1), which consists of two overlapping polyproteins that are extensively processed by viral proteases. The C-proximal region is processed at eleven conserved interdomain junctions by the coronavirus main or "3C-like" protease (Ziebuhr, Snijder, Gorbalenya, 2000 and Fehr, Perlman et al., 2015). The name "3C-like" protease derives from certain similarities between the coronavirus enzyme and the well-known picornavirus 3C proteases. These include substrate preferences, use of cysteine as an active site nucleophile in catalysis, and similarities in their putative overall polypeptide folds. The SARS-CoV-2 3CL protease sequence (Accession No. YP_009725301.1) has been found to share 96.08% homology when compared with the SARS-CoV 3CL protease (Accession No. YP_009725301.1) Xu, J.; Zhao, S.; Teng, T.; Abdalla, A. E.; Zhu, W.; Xie, L.; Wang, Y.; Guo, X.; Systematic Comparison of Two Animal-to-Human Transmitted Human Coronaviruses: SARS-CoV-2 and SARS-CoV; Viruses 2020, 12, 244; doi:10.3390/v12020244. Very recently, Hilgenfeld and colleagues published a high-resolution X-ray structure of the SARS-CoV-2 coronavirus main protease (3CL) Zhang, L.; Lin, D.; Sun, X.; Rox, K.; Hilgenfeld, R.; X-ray Structure of Main Protease of the Novel Coronavirus SARS-CoV-2 Enables Design of α-Ketoamide Inhibitors; bioRxiv preprint doi: https://doi.org/10.1101/2020.02.17.952879. The structure indicates that there are differences when comparing the 3CL proteases of SARS-CoV-2 and SARS-CoV. In the SARS-CoV but not in the SARS-CoV-2 3CL protease dimer, there is a polar interaction between the two domains III involving a 2.60-Å hydrogen bond between the side-chain hydroxyl groups of residue Thr285 of each protomer, and supported by a hydrophobic contact between the side-chain of Ile286 and Thr285 Cγ2. In the SARS-CoV-2 3CL, the threonine is replaced by alanine, and the isoleucine by leucine when compared with the same residues in the SARS-CoV 3CL. The Thr285Ala replacement observed in the SARS-CoV-2 3CL protease allows the two domains III to approach each other somewhat closer (the distance between the Ca atoms of residues 285 in molecules A and B is 6.77 Å in SARS-CoV 3CL protease and 5.21 Å in SARS-CoV-2 3CL protease and the distance between the centers of mass of the two domains III shrinks from 33.4 Å to 32.1 Å). In the active site of SARS-CoV-2 3CL, Cys145 and His41 form a catalytic dyad, which when taken together with a with a buried water molecule that is hydrogen-bonded to His41 can be considered to constitute a catalytic triad of the SARS-CoV-2 3CL protease. In view of the ongoing SARS-CoV-2 spread that has caused the current worldwide COVID-19 outbreak, it is desirable to have new methods of inhibiting SARS-CoV-2 viral replication and of treating COVID-19 in patients.

Abstract: wherein R, R1, R2, R3, p, q and q′ are as defined herein, pharmaceutical compositions comprising the compounds, methods of treating coronavirus infection such as COVID-19 in a patient by administering therapeutically effective amounts of the compounds, and methods of inhibiting or preventing replication of coronaviruses such as SARS-CoV-2 with the compounds.


A differential radio frequency (RF) receiver includes a fully differential direct conversion receive chain, a subharmonic mixer in the receive chain, the subharmonic mixer configured to receive a differential radio frequency (RF) input signal and a local oscillator (LO) signal that is phase-shifted by a nominal 45 degrees, and a synthesizer having a voltage controlled oscillator and having at least one frequency divider to generate desired receive LO signals.

Radio frequency (RF) transmitters are found in many one-way and two-way communication devices, such as portable communication devices, (cellular telephones), personal digital assistants (PDAs) and other communication devices. An RF transmitter must transmit using whatever communication methodology is dictated by the particular communication system within which it is operating. For example, communication methodologies typically include amplitude modulation, frequency modulation, phase modulation, or a combination of these. In a typical global system for mobile communications (GSM) mobile communication system using narrowband TDMA technology, a Gaussian minimum shift keying (GMSK) modulation scheme supplies a clean phase-modulated (PM) transmit signal to a non-linear power amplifier directly from an oscillator.
In such an arrangement, a non-linear power amplifier, which is highly efficient, can be used, thus allowing efficient transmission of the phase-modulated signal and minimizing power consumption. Because the modulated signal is supplied directly from an oscillator, the need for filtering, either before or after the power amplifier, is minimized. Other transmission standards, such as that employed in IS-136, however, use a modulation scheme in which the transmitted signal is both phase modulated (PM) and amplitude modulated (AM). Standards such as these increase the data rate without increasing the bandwidth of the transmitted signal. Unfortunately, existing GSM transmitter hardware is not easily adapted to transmit a signal that includes both a PM component and an AM component. One reason for this difficulty is that in order to transmit a signal containing a PM component and an AM component, a highly linear power amplifier is required. Unfortunately, highly linear power amplifiers are very inefficient, thus consuming significantly more power than a non-linear power amplifier and drastically reducing the life of the battery or other power source.
This condition is further complicated because transmitters typically employed in GSM communication systems transmit in bursts and must be able to control the ramp-up of the transmit power as well as have a high degree of control over the output power level over a wide power range. In GSM this power control is typically performed using a closed feedback loop in which a portion of the signal output from the power amplifier is compared with a reference signal and the resulting error signal is fed back to the control port of the power amplifier.
The EDGE communication system attempts to increase the data transmission capability of a GSM communication system by including an amplitude modulation (AM) component in the transmit signal. However, when attempting to add an AM component to the GSM type modulation system, the power control loop will attenuate the amplitude variations present in the signal in an attempt to maintain a constant output power. In such an arrangement, the power control loop tends to cancel the AM portion of the signal.
Further, in those transmission standards in which both a PM signal and an AM signal are sent to a power amplifier, unless the power amplifier is very linear, it may distort the combined transmission signal by causing undesirable AM to PM conversion. This conversion is detrimental to the transmit signal and can require the use of a costly and inefficient linear power amplifier.
In the past, the transceiver components for such a communication system were typically implemented using multiple devices, also referred to as "chips." However, industry pressures to reduce cost, implementation complexity and power consumption and to extend battery life are driving the industry to attempt single chip architectures. Unfortunately, a single chip implementation for a GSM/EDGE transceiver presents many design challenges, especially in a system in which a closed power control loop is used to control output power of the transmitter. For example, when a closed loop power control system is implemented on the same chip as the transceiver components, the radio frequency (RF) on-chip isolation requirement between the components becomes a major factor affecting transceiver performance.
One of the advances in portable communication technology is the move toward the implementation of a low intermediate frequency (IF) receiver and a direct conversion receiver (DCR). A low IF receiver converts a radio frequency (RF) signal to an intermediate frequency that is lower than the IF of a convention receiver. A direct conversion receiver downconverts a received radio frequency (RF) signal directly to baseband (DC) without first converting the received RF signal to an intermediate frequency (IF). One of the benefits of a direct conversion receiver is the elimination of costly filter components used in systems that employ an intermediate frequency conversion.
A low IF or a direct conversion receiver allows the filter components to be implemented using electronic circuitry that can be located on the same device (i.e., "on-chip") as many of the receiver components. In a direct conversion receiver implementation, high-order (e.g., fifth-order or higher) active filters are used to convert the received signal from RF to DC. Unfortunately, because the filters are implemented using electronic circuitry on the same chip as the receiver components, the filter adds significant noise to the received signal. The added noise reduces the sensitivity of the receiver, thereby making such an active filter challenging to implement.
When converting a received RF signal either to an intermediate frequency signal, or directly to a baseband signal, one or more mixers are used to downconvert the received RF signal. A mixer combines the received RF signal with a reference signals, referred to as a "local oscillator," or "LO" signal. The resultant signal is the received signal at a different, and typically lower, frequency. One mixer technology used today is referred to as a "subharmonic" mixer. A subharmonic mixer uses an LO signal that has a lower frequency, and is typically on the order of one-half of the system LO signal. A subharmonic mixer generally produces lower "self-mixing" components and generally reduces or eliminates feedback to the system antenna. Unfortunately, blocking signals are amplified at the output of the low noise amplifier (LNA) and couple into the mixer core where they are downconverted and corrupt the desired signal at baseband.
In addition, the IP2 (second order intercept point) performance of the receiver is limited and is difficult to improve without the use of IP2 correction methodology, which requires additional area on the chip, increases complexity, and requires manufacturing calibration.

Direct conversion receiver having a subharmonic mixer


A method is provided for preparing a raw material for functional foods from vernalized, pre-germinated barley or wheat seeds, plumules cultured the vernalized, pre-germinated barley or wheat seeds, or a material resulting from the fermentation of the vernalized, pre-germinated barley or wheat seeds with lactic acid bacteria.

1. Field of the Invention
The present invention relates to a method for preparing a raw material for functional foods from barley or wheat seeds. More particularly, the present invention relates to a method for preparing a raw material for functional foods that exhibit antioxidant, antidiabetic and/or antiobesity activity, by vernalizing barley or wheat seeds or fermenting vernalized barley or wheat seeds.
2. Description of the Related Art
Temperature is a factor which has a great influence on the photoperiodism of various crops and plants. Particularly, temperature plays an important role in flowering and developing annual winter crops or biennial crops.
Many temperature plants must experience a period of low temperature or cold of from 2 to 6 weeks to initiate or accelerate the flowering process in the spring. For example, when winter-growing species (e.g., barley, wheat, etc.) are seeded in the spring, their germination is delayed or does not occur.
Trofim Denisovich Lysenko, a soviet agronomist, advanced the theory that the length of the vegetative period of plants is dependent on not only their inheritance but also the external environment that exists when the plant is growing. He asserted that the poor germination of winter-growing crops sowed in the spring is attributed to the condition of the temperature being high after sowing, based on the finding that when they are sowed after exposure to the prolonged cold, seeds of winter-growing crops could readily germinate like spring-growing crops.
The artificial low-temperature treatment which allows winter-growing species to be sowed in the spring is termed "vernalization", and effective vernalization can be achieved at a temperature range of from 0 to 10° C.
Like photoperiodism, responses to cold exposure may be divided into qualitative and quantitative responses. Without the experience of the prolonged cold of winter, the species of qualitative responses show hibernalism, that is, the property of plants whereby they remain for an indefinitely long period in the phase of tillering without flowering stems while the species of quantitative response show delayed flowering.
Depending on treatment temperature, vernalization may be classified into low-temperature vernalization (0˜10° C.) and high-temperature vernalization (10˜30° C.). Also, there are two vernalization treatments according to the time of vernalization: seed vernalization and bulb vernalization which target pregerminated seeds and bulbs, respectively.
Winter-growing wheat plants such as barley, wheat, etc. are of the seed vernalization variety whereas cabbages and rapes are representative of bulb vernalization plants.
Lactic acid bacteria is the generic name for bacteria that utilize saccharides such as glucose as an energy source with the concomitant production of lactic acid. In the body, lactic acid bacteria show various beneficial functions including inhibiting the growth of harmful bacteria, bowel regulation, reducing the blood cholesterol level, anticancer activity, and ameliorating constipation and diarrhea. The genera that comprise lactic acid bacteria are at its core Streptococcus, Pediococcus, Leuconostoc, Lactobacillus, and Bifidobacterium.
Lactic acid bacteria are applied to food processing, typically aiming at improving the preservability, favor and/or functionality of foods.
For example, Korean Patent Laid-Open Publication No. 2010-0092786 discloses the antidiabetic activity of the food prepared by fermenting an extract from a mixture of Ganoderma lucidum and bitter buckwheat with Lactobacillus. Korean Patent Laid-Open Publication No. 2010-0059278 discloses a method for manufacturing savor-improved tea by treatment with lactic acid bacteria. The inhibitory activity of soybean fermented by complex Kimchi lactic acid bacteria against food poisoning bacteria is described in Korean Patent Laid-Open publication No. 2010-0020123. Korean Patent Laid-Open Publication No. 2008-0074290 discloses the application of lactic acid bacteria to the production of a beverage made from birch tree fluid that has improved perservability.
Leading to the present invention, intensive and thorough research into functional foods, conducted by the present inventors, resulted in the finding that when subjected to vernalization and optionally fermentation with lactic acid bacteria, barley and wheat seeds were provided with various functionalities including antioxidant activity, antidiabetic activity and antiobesity activity, higher than those of germinated seeds.

Method for preparing raw material for functional foods from barley or wheat seeds


A system and method for automated single cell capture and processing is described, where the system includes a deck supporting and positioning a set of sample processing elements; a gantry for actuating tools for interactions with the set of sample processing elements supported by the deck; and a base supporting various processing subsystems and a control subsystems in communication with the processing subsystems. The system can automatically execute workflows associated with single cell processing, including mRNA capture, cDNA synthesis, protein-associated assays, and library preparation, for next generation sequencing.

With an increased interest in cell-specific drug testing, diagnosis, and other assays, systems and methods that allow for individual cell isolation, identification, and retrieval are becoming highly desirable. Single cell capture systems and methods have been shown to be particularly advantageous for these applications. However, associated processes and protocols for single cell capture and subsequent analysis often must be performed in a particular order and with a high precision in order to properly maintain the cells. As such, these processes can be time consuming for the user, as well as result in damage to the cells or otherwise unfavorable results if they are not performed properly (e.g., through mistakes in pipetting, through a mix-up of reagents, etc.). In particular, these novel high throughput single cell cytometry assays have great utility in translational medicine, personalized therapy selections, clinical diagnostics, and/or other applications of use, but lack of automation prevents proper performance by novice users, thereby limiting throughput.
Thus, there is a need in the cell capture and cell processing field to create a new and useful system and method for single cell capture and processing.

System and method for automated single cell processing


A device, system, and method for suppressing electromagnetic interference (EMI). In one embodiment, an EMI suppression device includes a compound ferrite core having an inner ferrite core and an outer ferrite core. The inner core includes a through hole in which a conductor may be mounted, and the outer core includes a hole in which said inner core is mounted in a concentrically offset manner. The outer core is rotatably adjustable with respect to the inner core in a manner such that the ferrite circuit cross-section area may be varied. The magnetic reluctance of the compound core is controlled in accordance with EMI suppression requirements by adjusting the circuit cross-section area.

1. Technical Field
The present invention relates generally to noise suppression devices and systems and, in particular, to in-line modules for attenuating electromagnetic interference transmitted to or from electrical and electronic circuits.
2. Description of the Related Art
Electronic systems such as power supplies and computers often radiate and conduct electromagnetic noise at various frequencies. Such emissions cause undesirable electromagnetic interference (EMI) that negatively impacts the host circuitry as well other electronic equipment in spatial or electrical proximity to the system.
The dramatic proliferation of electronic processing devices, such as personal computers (PCs), has resulted in printed circuit board (PCB) designers being faced with increasingly strict electromagnetic compatibility (EMC) regulations. For example, the Federal Communications Commission (FCC) has enacted the so-called "open chassis" EMI regulations that strictly limit the electromagnetic emissions that subject devices may generate. The open chassis criteria generally transfer responsibility to the manufacturer for the regulation of radiation generated by on-board components, such as integrated circuits (IC) modules, from a shielded enclosure (e.g., a computer chassis or enclosure) housing the components to the housed components themselves, such as a PC motherboard. Such emissions, which would otherwise be sufficiently attenuated by the shielded enclosure to satisfy the prior "closed chassis" regulations, must now be sufficiently attenuated independently of enclosure shielding. Satisfying the open chassis regulations enables radiating devices, such as motherboards, to be more flexibly distributed independent of a particular shielded enclosure.
The FCC's open chassis regulations are specified in Table 1 below.
TABLE 1Field Strength Limits for UnintentionalRadiators at a Distance of 3 MetersFrequency of EmissionField Strength(MHz)(microvolts/meter)30–88100 88–216150216–960200>960500
Given the tendency of EMI to generate undesired high-frequency current loops in the motherboard of a computing system and in view of the foregoing regulations, EMI is a major limitation on increasing processing speed.
So-called common-mode current is the primary source of EMI in many electronic systems. Common-mode is a current conduction mode in which currents, present in two or more conductors, are flowing in phase and with equal magnitude within each conductor. Common-mode current is the component of signal current that induces electric and magnetic fields that do not tend to cancel each other. For example, in a circuit with one outgoing signal conductor and one return "ground" conductor, the common mode current is the component of total signal current that flows in the same direction in both conductors.
Efforts undertaken to address the growing problems and limitations associated with common-mode EMI in electronic systems include meticulous layout of traces in PCBs, decoupling capacitors, and multiple-layer PCBs. Each of these techniques suffers one or more drawbacks in terms of PCB board space economy, high frequency limitations, and cost and complexity. While chassis shielding has long served as a primary EMI attenuation technique, and as explained above, current FCC regulations in combination with the desire for manufacturing flexibility, necessitate additional EMI control independent of that provided by chassis shielding.
In addition to the foregoing shielding and decoupling techniques, common-mode EMI may be suppressed using a ferrite device, often referred to a common-mode choke. Ferrites are utilized as an inexpensive supplement or alternative to suppress common-mode EMI in the electronic industries. A ferrite is generally a type of ceramic material often comprising divalent metals having unique molecular properties that generate high magnetic flux density in the presence of a magnetic field. Ferrites are typically axially mounted around signal path media such as pins or wires. Ferrite beads, cores, or other dissipating elements function by selectively absorbing electromagnetic energy at EMI frequencies. More specifically, a ferrite device absorbs reactive power in its magnetic field, which induces a voltage that opposes the interference signal current flow (typically single direction common mode interference current). Simply put, the common-mode interference signal is trapped in the electrical and magnetic fields of the ferrite and is dissipated as heat.
While effective for suppressing EMI in a variety of electronic systems, there remain problems with conventional design and deployment of such devices. One problem relates to the need for deploying such a device, such as a ferrite bead or toroid, onto a wire that is pre-connected at its ends. To address this problem, split or bisected ferrite devices are commonly utilized to permit installation on pre-connected cables. However, given the very tight geometric tolerances affecting ferrite performance, bisecting the ferrites increases the likelihood of slight geometric anomalies that may adversely affect EMI suppression performance.
Another significant problem associated with conventional ferrite design and deployment relates to the relative lack of tunability for a given application. A common expression of a ferrite's performance is in terms of permeability (μ). Permeability is the ratio of the magnitude of magnetic induction to magnetizing force and is variable as a function of frequency. The performance of a ferrite may be customized by adding metal oxides in various amounts to adjust the permeability and impart attenuation characteristics suited for a specified EMI suppression application. Therefore, setting of ferrite performance for a particular application requires relatively precise pre-estimation of the expected EMI environment. Given the dynamic nature of electronic system environments in which varying operating conditions and system wear may result in significant variations in the EMI environment, and in which environmental conditions such as temperature affect ferrite performance, conventional ferrites are often not optimally tuned for a given environment.
It can therefore be appreciated that a need exists for an improved device, system and method that addresses the foregoing problems. The present invention addresses these as well as other problems unaddressed by the prior art.


Methods, apparatuses and systems for populating a data structure. The data structure may be established in a memory unit and may have a total number of N slots for entries. In this case, N is defined as an integer representing the total number of slots in the data structure, and N is further expressible as a power of two with an integer exponent x. Entries may then be stored into L slots of the data structure, with L being defined as an integer representing a number of slots that contain entries. To produce an index value, x bits of a binary representation of L may be swapped. A new data entry is then stored into an entry of the data structure represented by the index value.

Asynchronous Transfer Mode (ATM) includes a protocol for transmitting information over a network such as the Internet. ATM currently includes numerous standards that are publicly available. In ATM the flow of information, which may be referred to as traffic, may be specified as a number of cells transmitted per second. Cells are currently 53 byte sets of data that may be transmitted over an ATM link. Moreover, currently five of those 53 cell bytes are utilized to carry header information and the remaining 48 cell bytes are used to carry payload information that is being transmitted.
Modern networks may carry a variety of traffic, some of which may have strict timing requirements. With network protocols such as the ATM protocol, data traffic, including voice and video traffic, traverses a network via network devices such as ATM switches that assure that the appropriate connections are established, that the data reaches its destination via its designated connections, that bandwidth constraints are not exceeded and that timing requirements are met. Traffic flow through these network devices is often managed by a cell scheduler. In an ATM device such as an ATM switch, schedulers are used to manage the timing of cell transmission. Traffic with rigid timing requirements, such as real-time voice and video traffic must be accommodated in those schedulers along with other data traffic. The ATM protocol addresses those timing issues by designating special classes or categories of service for handling time sensitive data. ATM traffic thus generally has a quality of service (Qos) guarantee that varies depending on the specific requirements of the traffic type. Two classes of service that maintain end-to-end timing relationships across an ATM network are the constant bit rate (CBR) class of service and the variable bit rate real-time (VBR-rt) class of service, which are described in the ATM standards.
ATM cell schedulers generally include tables having slots that are populated according to the requirements of the traffic being scheduled such as CBR and VBR-rt along with other types of traffic having less demanding timing requirements. Thus, each cell to be transmitted may be identified in a slot of the table and the identified cells may be transmitted in the order in which they are identified in the table.
ATM traffic can enter and exit a network device such as a switch via one or more ports, with each port carrying a sub-stream of traffic. Certain of those sub-streams may furthermore be constant-bandwidth sub-streams and carry real-time traffic. Constant bandwidth sib-streams also adhere to timing requirements to assure constant bandwidth. To maintain proper timing in a scheduler table that sequentially runs through all slots in the table to find the next ATM cell to transmit, the distance between all consecutive table entries of a sub-stream of such real-time data should be equal. That distance between entries related to a sub-stream may be referred to as a step, may be measured in terms of a number of slots between entries for that sub-stream in the table, with each consecutive entry for a particular sub-stream of real-time data being a step apart, and may be referred to as Z.
When populating such a table with information from numerous sub-streams in accordance with timing requirements, the proper slots must be available and identified for population. Checking for slot availability generally becomes more laborious as more entries are made in the table and the table becomes more densely populated.

System, method and apparatus for preparing a table for a cell scheduler


A light for an aircraft comprises a holder for carrying a first group of light emitting diodes arranged along a curvilinear line and a first reflector having an elliptic reflective partial surface defining a plurality of focal points forming a first curvilinear focal line coinciding with the light emitting sites of the first group of light emitting diodes and second focal point or curvilinear focal line. The light further includes a second optical unit comprising a single further focal point or curvilinear focal line that coincides with the second focal point or focal line of the first reflector. The light further includes a second group of light emitting diodes displaced axially with respect to the first light emitting diodes, which emit light that bypasses the second focal point or focal line of the first reflector of the first optical unit.

1. Field of the Invention
The present invention relates to a light for an aircraft and, in particular, to an external light for an aircraft. While the present invention can be used primarily for each type of aircraft light, preferably the present invention is for a head light; taxi light, and runway turn-off light of an aircraft.
2. Description of the Prior Art
In the past, in the technical field of aerospace applications, light sources have been based on gas discharge technology or filaments. For several years, aircraft lights based on LED technology have found ever stronger commercial use. Examples for LED-based aircraft lights for different purposes are disclosed in U.S. Pat. No. 6,679,618, U.S. Pat. No. 7,572,030, US-A-2007/0164875, WO-A-2009/156349, EP-B-1 217 663, EP-B-1 264 767, EP-B-1 552 983, EP-B-1 836 437, and GB-B-2,350,176.
In order to fulfill the official requirements of the Federal Aviation Association (FAA) with regard to the spatial light intensity distribution based on LED technology, a plurality of LEDs have to be arranged. In these designs, the available space and cooling capacities are only two of several concerns to be dealt with in order to obtain a high intensity light.
From U.S. Pat. No. 1,275,120 a projecting apparatus is known in which an ellipsoid reflector is used for illuminating a slide or film, i.e. a two-dimensional surface is illuminated to be projected on a projection screen or the like surface. Such a projection apparatus cannot be used in a lamp in which the light has to be directed in a pre-determined special light intensity distribution as in case of an aircraft light.
From WO-A-2008/031405 there is known a reflector emitter for a strong light beam using a plurality of lower-power lamps, revolution-ellipsoid sections are formed from revolution ellipsoids which are additionally cut in the focal-point plane. The sectional planes of all the mirrors are arranged in one common base plane and the mirror surface f the further concave mirror is directed in the direction opposite the others. The light sources are arranged in the first focal points of the revolution-ellipsoid sections and their second focal points and the focal point of the further concave mirror coincide. All the light beams which are incident on the surface of the revolution-ellipsoid sections are reflected onto the further concave mirror. Here, the light beams form a shaped bundle which leaves the reflector emitter at right angles to the base plane through the aperture.
Moreover, in WO-A-2008/089324 a folded light path LED array collimation optic is described which relates to a compact optical assembly which improves collimation of light produced by multiple LED light sources in a light engine. A shaped primary reflector located over the light engine reflects the light toward a larger shaped secondary reflector. The shapes of the reflectors are selected to cooperatively produce a highly collimated light beam. Color mixing may be improved by providing a plurality of facets on the reflective surfaces of at least one of the primary reflector or the secondary reflector.
Due to limited spaces and weight limitations in aircrafts, it is often desirable to include several light functions in a single light. This is true e.g. for the landing light, taxi light, and potentially runway turn-off light (RTO) which typically are realized by different housings using relative large mounting spaces which in particular at the noise landing gear (NLG) is limited.


A mounting apparatus is used to fix a flash drive mounted on a circuit board with a connector. The mounting apparatus is mounted on the circuit board and receives the flash drive and connector therein. The mounting apparatus includes a first sidewall and a second sidewall opposite to each other. An elastic piece and a resilient portion extend toward each other respectively from the first and second sidewall, to resist against opposite sides of the flash drive in response to the flash drive engaging with the connector.

1. Technical Field
The present disclosure relates to a mounting apparatus for flash drives.
2. Description of Related Art
In some computer, programs for driving some elements mounted on circuit boards of the computers are stored in flash drives, such as universal serial bus (USB) flash drives, which are detachable from the computers. However, these USB flash drives are generally engaged with connectors of the computers directly. As a result, the USB flash drives may easily disengage from the corresponding connectors after impact and vibration of the computers or the USB flash drives.

Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd.


The present invention relates to the motion reconstruction method from inter-frame feature correspondences of a singular video stream using a motion library.

The present invention relates to the motion reconstruction method from inter-frame feature correspondences. More particularly, the invention relates to the method of obtaining 3D motion information from a singular video stream by transforming the similar motions retrieved from a motion library and fitting them into the input image information.
Recently, the production of a virtual character animation using a motion capture technology is becoming very active.
The advantage of using the motion capture technology is that real motions can be produced in a fast and efficient way in comparison to the other conventional animation production methods.
Since the captured motion clips are short and generally related to particular characters or environments, there has been a continues development of various types of editing tools which recycle the captured motions for the production of new animations.
Based on these developed tools, animators can appropriately use the captured motions according to various requirement of the virtual characters and environments.
The monocular images captured by a camera is the most standard medium for storing the motions of a human and to date many researchers have been conducting experiments for various purposes in order to extract human motions from the monocular images.
There has been continues research activities on automatic reconstruction of motions from images based on an image analysis technology. In general, these researches rely on a probabilistic model for ascertaining the position of an articulated body.
Among the examples, Azarbayejani, et al (C. Wren, A. Azarbayejani, T. Darrel and A. Pentland. Pfinder: Real-time Tracking of the human body. IEEE Trans. Pattern Analysis and Machine Intelligence, 1991) proposed a method of real time tracking of a human body from the images obtained from one or plurality of cameras.
The above paper classifies a human body into a number of blobs and 3D location of a blob is tracked by the probabilistic model.
Bregler and Malik (C. Bregler and J. Malik. Estimation and tracking kinematics chains. In Proc. IEEE Conf. Computer Vision and Pattern Recognition, 1998.) expressed the kinematics of a multi-articulated body in terms of a twist and exponential basis. Based on this expression, the motions of a human body are inferenced from the images obtained from one or plurality of cameras.
Sminchisescu and Triggs (C. Sminchisescu and B. Triggs. Covariance scaled sampling for monocular 3D body tracking. In Proc. IEEE Conf. on Computer Vision and Pattern Recognition, 2001.) brought the attention to the difficulty of reconstructing images based 3D information due to the vagueness and occlusion. They attempted to obtain a nearest solution using an optimization method.
In order to avoid local minimum solutions during an optimization, the paper uses the covariance-scaled sampling method in conjunction with a numerical optimization method.
Also, it concentrated on some effective methods which are already known to some researchers for extracting a previously known 3D information from 3D feature information.
For example, Zheng and Suezaki (J. Y. Zheng and S. Suezaki. A model based approach in extracting and generating human motion. Proceedings of Fouteenth International Conference on Pattern Recognition, 1998.) proposed a model based method of capturing the motions of a multi-articulated body from monocular images.
The above paper disclosed the production method of 3D motions from total images by designating a number of key frames, obtaining 3D information from the key frames and storing them.
Rehg, et al (J. M. Rehg and T. Kanade. Visual tracking of high DOF articulated structures: an application to human hand tracking. European Conf. on Computer Vision, 1994.) attempted to reconstruct 3D information using a probabilistic approach that includes a kinematics model and limiting conditions of articulation angle as well as other limiting conditions.
Kakadiaris and Metaxas (I. Kakadiaris and D. Metaxas. Model-based estimation of 3D human motion with occlusion based on active multi-viewpoint selection. In Proc. IEEE Conf. Computer Vision and Pattern Recognition, 1996.) disclosed the method of obtaining a ratio for the given model from one piece of image using anthropmetry information.
Taylor (C. J. Taylor. Reconstruction of articulated objects from point correspondences in a single uncalibrated image. Computer Vision and Image Understanding, 2000.) disclosed the method of obtaining a detailed 3D information based on a previously known model using the foreshortening phenomenon which occurs from an image.
Liebowitz and Carlsson (D. Liebowitz and S. Carlsson. Uncalibrated motion capture exploiting articulated structure constraints. In Proc. 8th International Conference on Computer Vision, 2001.) disclosed the method of obtaining a detailed dynamic information of a multi-articulated body based on the images obtained from a plurality of uncalibrated cameras.
The above paper uses a limiting condition which states that the body ratio of a multi-articulated body is constant with respect to time.
Recently, a number of fresh attempts have appeared which shed a new light into the problem of motion construction.
For example, Howe, et al (N. R. Howe, M. E. Leventon, and W. T. Freeman. Bayesian reconstruction of 3D human motion from single-camera video. Cambridge Research Laboratory TR-CRL-99-37, 1999.) attempted to solve the problem of reconstructing 3D motions from monocular images using the relationship between 2D features formed by training and 3D positions.
The above paper claimed that the loss of depth information can be reproduced by using the above relationships.
Sidenbladh, et al (H. Sidenbladh, M. J. Black, and D. J. Fleet. Stochastic tracking of 3D human figures using 2D image motion. European Conference on Computer Vision, 2000.) obtained the patterns of human's walking motion through a training. By using these patterns, an attempted has made to reconstruct an arbitrary walking motion.
The common characteristic for this type of problems is that it regards the 3D motion tracking problems as an inference problem and approached them accordingly.

Motion reconstruction method from inter-frame feature correspondences of a singular video stream using a motion library

Abstract: The motion library is constructed through a motion capture system which is becoming more actively used or skilled animators.

Abstract: The present invention comprises the detailed information on the whole processes from images to motions. These processes are very simple to implement and straight forward.

Abstract: The total movement of a motion can be effectively inferenced and this technology can directly used for various fields in which human motions are produced from the images.

Korea Advanced Institute of Science and Technology


A pump apparatus is provided which comprises a plurality of displacement pumps each connected to a check valve apparatus. The displacement pumps each comprises a reciprocating piston within a housing having an interior wall spaced apart from the piston. The check valve apparatus comprises two check valves that control fluid flow under pressure exerted by the reciprocating piston from a fluid reservoir to a point of use of the fluid. Pistons of the displacement pumps are driven by a common motor.

This invention relates to an integrated ratio pump and check valve apparatus for pumping a plurality of discrete liquid volumes to points of use of the liquid volumes. More particularly, this invention relates to an integrated ratio displacement pump and check valve apparatus for pumping a plurality of discrete liquid volumes to points of use.
At the present time, discrete liquid volumes are pumped with a syringe pump comprising a barrel, a face seal which moves within the barrel and a reciprocating plunger attached to the face seal. The syringe pump includes a valve construction formed of a polymeric composition which directs the pumped liquid volumes to a point of use. The valve construction includes a housing (stator) having a hollow, essentially interior surface into which is press fit a mating rotor. The rotor is provided with fluid passageways that control flow of liquid into the syringe pump and flow of liquid from the syringe pump while providing sealing between a pump inlet and a pump outlet. This configuration of syringe pump and rotor-stator valve requires two motors, one to drive the syringe and a second to drive the rotor.
While the available syringe pumps have been useful for their intended purpose, they also have disadvantages. In order to attain a tight fit between the barrel and the face seal, the manufacturing of both the barrel and face seal must be made at tight tolerances. In addition, when utilizing the most commonly used materials comprising a glass barrel and a polytetrafluoroethylene (PTFE) face seal, undesirable shedding of the PTFE occurs which contaminates the liquid being pumped. Furthermore, a tight fit between the barrel and face seal results in chattering of the face seal during its movement within the barrel. This leads to a loss of control of the liquid volume being pumped. In addition, the average useful life of presently available syringe pumps is only about 10 to about 100,000 cycles.
The presently available syringe pumps also are capable of pumping only a single liquid. Oftentimes it is desirable to provide a mixture of two or more liquid compositions for specific purposes. The provision of such liquid mixtures is not possible with presently available syringe pumps.
Accordingly, it would be desirable to provide a pump apparatus capable of delivering discrete liquid volumes to a point of use such as different areas of a sample tray in a manner which is repeatable for long time periods of 1,000,000 cycles or more. In addition, it would be desirable to provide such a pump apparatus which avoids shedding of particles during pumping. Furthermore, it would be desirable to provide such a pump which eliminates the need for a motor to activate a seal in order to direct fluid to a desired point of use. In addition, it would be desirable to provide such a pump apparatus capable of pumping a plurality of liquids in precise volume ratios.

Integrated ratio pump and check valve apparatus


A sensor, system and method for determining the various Z-directional properties of a sheet by measuring the caliper of a moving sheet of material at a plurality of pressures. The invention employs a caliper gauge and a set of pressure transducers that can measure and send signals indicative of the caliper as well as pressures exerted on the sheet. The signals are then digitized by an analog-to-digital converter and sent to a computer. The computer uses the compressibility data to construct a compression stress-strain diagram where the slope of the curve in the linear region of the curve is defined as the compression modulus of elasticity which can be empirically correlated to the tensile modulus of elasticity for various grades of paper. The tensile modulus of elasticity can be then used in various formulas to determine other Z-directional physical properties of the sheet, such as tensile strength, extensional stiffness and Scott bonding.

(1) Field of the Invention
The present invention relates to the field of sensors for measuring the properties of a sheet, and more particularly to a sensor and system including a caliper gauge for measuring sheet compressibility subjected to a plurality of pressures.
The invention uses the compressibility measurements to compute a compression modulus of elasticity which can be used to derive various Z-directional properties of the sheet, such as the tensile modulus of elasticity, the Z-directional tensile strength, extensional stiffness and Scott bonding.
(2) Description of the Related Art
Various types of caliper gauges are known in sensor technology and are used for measuring the thickness of rapidly moving sheet material. One type of caliper gauge is called a "contacting caliper gauge." Contacting caliper gauges typically have two opposing pads which are forced into contact with opposite sides of a sheet. The distance between the pads is measured and directly relates to the sheet thickness or "caliper."
It has been recognized that the aerodynamic design of the caliper pads must be considered if the pads are to be maintained on or near the sheet surface with relatively little external force. A previous caliper gauge having aerodynamically designed caliper pads is disclosed in the commonly assigned U.S. Pat. No. 4,901,445 to Mathew G. Boissevain, et al. This patent is incorporated herein by reference.
However, applicants are not aware of caliper gauges being used to simultaneously measure the compressibility of a sheet at a plurality of pressures or using such measurements to compute a compression modulus of elasticity which can be used to compute the tensile modulus of elasticity and to derive various Z-directional physical properties of the sheet, such as Z-directional tensile strength, extensional stiffness and Scott bonding.
One of the most critical properties involved in the manufacture of paper is its strength. Virtually all paper manufactured is sold with a strength specification of some sort, and acceptance of a manufacturer's paper depends on being able to meet this requirement. Paper strength has three basic orientations: 1) the machine direction, 2) the cross-direction, and 3) the Z-direction. The machine direction refers to the primary direction of sheet travel through the papermaking machinery. The cross-direction refers to the direction across the width of the sheet, in the plane of the sheet and perpendicular to the machine direction. The Z-direction extends perpendicular to the plane defined by the machine and cross-direction and is also referred to as the thickness direction.
A previous system for continuous determination of sheet strength in the cross-direction and machine direction is disclosed in the commonly assigned U.S. Pat. No. 4,866,984 to Paul J. Houghton which is incorporated by reference. This system does not, however, determine sheet strength in the Z-direction, and therefore does not provide a complete picture of paper strength. In addition, due to the alignment of wood fibers, which are the main constituent of paper, the strength for each orientation is substantially different.
The Z-directional strength of paper is usually given in terms of an empirical, destructive test. A common test is the Scott bond test where the Z-directional strength is determined by measuring the bonding between the different layers of fibers through the sheet. In the Scott bond test, a strip of paper or sample is delaminated by applying an in-plane shear force. One side of the sample is double-taped to a fixed support. The other side is taped to an "L" bracket. A pendulum is then released to hit the vertical side of the bracket and shear the sample. The energy lost in the delamination can be measured from the stopping position of the pendulum.
In another such destructive test, the Z-directional tensile test, a sample is delaminated by pulling on both surfaces in the Z-direction with an equal force. Double-sided tape is used on each side to transfer the stress to the sample. The paper strength is determined by measuring the force exerted on the paper when it ruptures.
Of course, neither test can be performed "on-line" as the paper is being manufactured in order to avoid the production of substandard material. Instead, the sample must be taken from the end of a reel after the reel has been completed. Since papermaking is a high speed continuous process, large amounts of paper can be easily produced before strength can be confirmed by a later measurement. The result of the time-consuming, off-line testing is that the strength measurement provided by perhaps several square feet must be accepted as representative of the thousands of square feet making up the reel. Consequently, it would be highly desirable to measure paper strength on-line while it is being manufactured.
An article by Hall, On-Line ultrasonic Measurement of Paper Strength, Sensors (1990), based on research at the Institute of Paper Science and Technology, describes the use of commercial fluid filled wheels which are adapted for out-of-plane ultrasound velocity measurements and caliper measurements for moving paper webs. However, no on-line data is presented and there is no apparent disclosure of how to correlate these measurements with Z-directional paper strength.
Nonetheless, Z-directional strength is important to monitor and control on-line, both to the efficiency of the paper mill and the efficiency of the processes in the converting operations. In a paper mill, there are several processes, such as those employing sizing presses and coaters, where highly viscous materials are applied to the paper. In the process of applying and drying these materials, the sheet or portions of the sheet can be pulled apart in the Z-direction, causing build-up on the applicators and dryers. In addition, there are other areas where either the surface of a calender roll or the surface of the sheet is dampened which causes the sheet to adhere to the roll.
However, too high a value of Z-directional strength can also cause problems. For example, if the Z-directional strength is obtained from too much densification of the sheet by wet pressing, or other means, then certain properties such as opacity, folding stiffness and tear strength will be reduced. Also, it can be generally stated that the higher the strength, the higher the cost of manufacturing the paper.
The company that buys the paper and converts it into a product has similar types of Z-directional strength requirements. Many of the converting operations, such as corrugators, printers, coaters and laminators, also apply substances of high viscosity that create a Z-directional force on the sheet of paper. Here again, if the Z-directional strength in the paper is too low, portions of the sheet will be pulled apart or delaminate in the Z-direction causing either sheet breaks or build-up on the applicator rolls or drying equipment.
Thus, it would be desirable to be able to obtain the Z-directional strength, as well as other Z-directional properties such as tensile strength, extensional stiffness and Scott bonding on-line to achieve the strength required by both the papermaker and the converter, while at the same time optimizing cost and manufacturing efficiency.

Sensor, system and method for determining Z-directional properties of a sheet


The present invention relates to ADAMTS-1 and uses thereof. The present invention also relates to fragments of ADAMTS-1 and methods of inhibiting cell growth and metastasis. The present invention also provide methods of identifying inhibitors and activators relating to the function of ADAMTS-1.

The members of ADAMTS (A Disintegrin And Metalloproteinase with ThromboSpondin motifs) family belong to ADAM (A Disintegrin And Metalloproteinase) family of multifunctional proteins that display a significant sequence homology with snake venom metalloproteinases. The amino-terminal half of ADAMTS is similar to that of ADAM, which contains propeptide, metalloproteinase, disintegrin, and cysteine-rich domains; while the C-terminal half of ADAMTS is completely different and contains thrombospondin type I-like (TSP) motifs that are originally found in thrombospondin 1 and 2 and spacer region. At least 18 members of ADAMTS have been identified. ADAMTS-1 is the first member identified and is expressed in many embryonic tissues and in tumors. Disruption of ADAMTS-1 gene results in reduced growth, abnormalities in uteral, adrenal, and dipose tissues, and female infertility.
ADAMTS-1 cleaves aggrecan and versican in vitro, however, physiologic substrates of ADAMTS-1 remain to be identified. In addition, ADAMTS-1 is cleaved at the spacer region by matrix metalloproteinases (MMPs). The role of ADAMTS-1 in tumor growth and metastasis is not well established. ADAMTS-1 was found to display anti-angiogenic and anti-tumor activity, however, increased expression of ADAMTS-1 was correlated to the enhanced metastatic potential of pancreatic cancers, and studies have shown that ADAMTS-1 is one of the genes up-regulated in the breast cancer with elevated metastatic activity.
Thus, there is a need to clarify the biologic role of ADAMTS-1. Furthermore, there is a need to identify compounds and/or compositions that can be used to treat cancer or inhibit cell growth.

The Trustees of the University of Pennsylvania


RF power device module (500) having an RF power device chip (206) which integrates an RF power device (208) with at least one of DC detector circuits (201, 202), RF detector circuits (203, 204), and thermal detector circuit (235) which cooperate with optical emitter/detector components (213) that supports a bi-directional optical link (210) made through free space with diagnostic processing and control circuits implemented on a separate chip (214) mounted within the same enclosure (205). The bi-directional optical link (210) enables interpretation of detection signals (227) received from the RF power device chip (206) and the feed back of default or other management and control signals (229) sent back to the RF power device chip (206) in response to the detected and analyzed conditions. The RF power device module (500) can be used in RF power transistors, such used in a base station, or mobile or portable transmitters, used in telecommunications, or in RF power amplifiers and instrumentation amplifiers in general.

Communication systems are known comprising a plurality of base stations that provide communication services to remote or mobile units located in corresponding service coverage areas of the base stations. Remote unit receivers include circuits for measuring the signal strength of received signals and transmitting a received signal strength indication (RSSI) to a monitoring base station to indicate the signal strength of the carrier received by the receiver. To account for changes in RSSI as the remote unit moves and so forth, the serving base station will issue commands directing the remote unit to increase or decrease its power as the need arises. Typically, as the remote unit moves to the periphery of or into an obstructed location in the serving base station coverage area, the transmit power of the remote unit as well as the transmit power of the base station must be increased to account for an increase in path losses between the serving base station and the remote unit.
If insufficient RF power is produced by the base station transmitter to transmit a modulated carrier, the remote receiver cannot accurately demodulate voice signals and decode the data. On the other hand, if the base station's transmitter transmits the carrier signal with too much power, the performance of adjacent channels may be affected and possible jamming thereof may result.
RF power devices and circuits, such as those used in cellular telephone base stations, typically include power amplifiers. As well known, base stations are often exposed to a broad temperature range and varying RF power. In addition to variations in temperature and RF output power, there are also variations in bias voltage, frequency and load impedance. A need often arises to compensate for inadvertent changes of bias current in RF power amplifiers over temperature, power fluctuations, bias voltage frequency, or load impedance. In non-constant envelope applications such as code division multiple access (CDMA) or time division multiple access (TDMA), in particular, control of quiescent current is often needed to improve the response linearity or gain flatness of the power amplifiers, while for constant envelope applications such as the global system for mobile communications (GSM) bias voltage drop compensation is often needed to control output power or efficiency.
FIG. 1 represents a conventional system 100 for monitoring RF power device performance and handling fault management in which input and output direct current (DC) detection circuitries 101, 102, and reverse and forward RF detection circuitries 103, 104, are used to sense the operation state of the RF power device 108. They are implemented in a different chip, wafer or discrete components mounted on printed wiring board or substrate from the RF power device chip 106. The detected information is formatted by data formatting circuitry 111 and then transmitted via hardwire means 112 to separate diagnostic and control circuitry 114 used to process, interpret, and diagnose the detected information. The hardwire means 112 is typically an electrical connection made conventionally via printed traces on a printed wiring board. Fault management and control signals are relayed back to the RF power device 108 via the same hardwire means 112 on the PC board.
However, the use and reliance on the hardwire means as the communication link for the detected information and the fault management signals has problems. For instance, the hardwire electrical connection is subject to coupling from the high power RF signal associated with the operation of the nearby RF power device. This can lead to malfunctions in the circuitries, unless appropriate bypassing components are provided in the interconnect lines and circuitry, that typically increases design complexity and manufacturing costs. The hardwire means also can cause instability due to the creation of sneak feedback paths or RF loading of the RF amplifier input and output matching circuits.
Another drawback associated with conventional RF power device fault detection systems is the necessity of using an assembly of different dies, chip set or discrete components mounted on printed wiring board or substrate, to support the detection circuitries and the RF power device. Interconnecting these various separate dies for intercommunication and operation creates design, fabrication and performance issues. The off-chip arrangement of the detection circuitry can induce mismatch errors in the RF power circuitry. Also, the hardwired multi-chip arrangements are susceptible to interconnect failures, which reduces reliability. The inter-chip hardwiring arrangement also can slow the system's performance speed.
There are also conventional circuit tester systems applied to test a circuit by making use of one or more coaxial cables or optical fibers as an optical interface that physically extend between a device-under-test and a probe card, which is in turn connected to a load card and a circuit tester. As will be appreciated, communication links requiring physical interfaces between a device-under-test and a circuit tester can be more tolerable when the device-under-test is not yet installed in an enclosure or other location difficult to access under which it will be actually put into service.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are typically not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention.

RF power device with on-chip digital control and optical interface


A method of operating a fuel cell includes supplying a gas stream to the fuel cell and oscillating the gas stream.

Fuel cells conduct an electrochemical reaction to produce electrical power. The typical fuel cell reactants are a fuel source such as hydrogen or a hydrocarbon, and an oxidant such as air. Fuel cells provide a DC (direct current) that may be used to power motors, lights, or any number of electrical appliances. There are several different types of fuel cells, each using a different chemistry.
Fuel cells typically include three basic elements: an anode, a cathode, and an electrolyte. Usually the anode and cathode are sandwiched around the electrolyte. The electrolyte prohibits the passage of electrons. Fuel cells are usually classified by the type of electrolyte used. The fuel cell types are generally categorized into one of five groups: proton exchange membrane (PEM) fuel cells, alkaline fuel cells (AFC), phosphoric-acid fuel cells (PAFC), solid oxide fuel cells (SOFC), and molten carbonate fuel cells (MCFC).
The anode and cathode are porous and usually include an electrocatalyst, although each may have a different chemistry. Fuel migrates through the porous anode and an oxidant migrates through the porous cathode. The fuel and oxidant react to produce various charged particles, which include electrons at the anode. The electrons cannot pass through the electrolyte and therefore become an electrical current that can be directed to an external circuit. The cathode conducts the electrons back from the external circuit, where they recombine with various ions and oxygen and may form water and/or other by-products. Often a number of fuel cells are arranged in a stack to provide a useful amount of electrical power.
In many fuel cell applications, supplies of fuel and oxidant are connected to a housing that contains the fuel cell. However, much of the fuel provided to the fuel cell is often underutilized. As fuel is provided to the anode of a fuel cell, the fuel available at the surface of the anode is usually consumed quickly, while fuel at some distance from the anode is consumed more slowly and must migrate toward the anode for more efficient consumption. This phenomenon results in a fuel concentration gradient within the fuel cell. The effective use of the fuel then depends on the gas diffusion rate with which the fuel migrates to reach the anode.
Currently, fuel concentration gradients and gas diffusion rates are significant inhibitors to fuel cell performance, especially so with solid oxide fuel cells that can operate using a variety of fuels. There have been some attempts to improve fuel cell performance by quickly providing fresh supplies of fuel to the surface of the anode to fully utilize the ability of the anode to consume fuel. However, this is currently done at the expense of exhausting much of the fuel unused through the system or using a complicated manifold system with significant pressure losses.

Hewlett-Packard Development Company, L.P.


A dispenser for spreadable foodstuffs or spreadable non-food substances allowing for dispensing of metered amounts of foodstuffs or non-food substances and spreading without the need for additional utensils that are not part of the packaging is disclosed. Dispenser is easily refilled with replaceable cartridges and designed to keep contents away from air as contents are dispensed.

The vast majority of packaging of spreadable foodstuffs lack any functionality to allow contents to be used directly from the packaging. The packaging for spreadable foodstuffs such as ketchup, mustard, cream cheese, peanut putter, jelly, etc. typically require a knife or other utensil not part of the food packaging to remove the foodstuff from a container and/or achieve spreading the foodstuff as desired. Even containers that allow for squeezing the foodstuff contained therein directly out of the packaging often still require a utensil not part of the food packaging to evenly spread the foodstuff. Such containers also often do not dispense foodstuffs easily as the void space of the container increases as foodstuff is consumed. Often the contents may splatter or take a significant amount of time to flow due to a large volume of air in the container. Air being introduced to the container during the products use also negatively affects product freshness.
Traditional food containers are also typically challenging for children, elderly, diasabled, or physically challenged individuals to use. Such containers also require utensils to be washed after every minor use of the product, which is a particular inconvenience during such activities as traveling, picnics, or other occasions where typical kitchen amenities are not present in addition to individuals who do not own a dishwasher.
Additionally, spreadable foodstuffs are often difficult if not impossible to measure via traditional means such as measuring cups. Very viscous foodstuffs such as peanut butter and cream cheese are difficult to measure with measuring cups since an accurate measurement may only be achieved by packing the product to remove any air left in the measuring cup. Even after an accurate measure is taken, it is extremely difficult to quantitatively transfer the measured product out from the measuring cup. A solution to accurate measurement and use of spreadable foodstuffs is particularly pertinent in restaurant settings where consistency is important. An accurate way to dispense spreadable foodstuffs is also important in home-settings for portion control and dieters.
The invention is also designed for use with a variety of non-food semi-solid or gelatinous substances. These substances include but are not limited to toothpaste, shoe polish, paints, cosmetics, thick oils, topical medications, and emollients. The typical containers for these substances are often the same and have the same limitations as those used for foodstuffs. These main limitations being the need for an additional utensils to remove and use the substance from the container, air being introduced to the containers over time as the substance is used, difficulty of use for children or individuals with physical limitations, and difficulty in measuring with measuring cups.


In gas phase polymerizations and copolymerizations of ethylene, reagents or cofeeds control the molecular weight, expressed as MI (wherein MI is measured according to ASTM D-1238 Condition E), of the resin product. Use of isopentane and electron donating compounds decrease MI; whereas, electron withdrawing compounds increase MI.

Polyethylene is produced commercially in a gas phase reaction in the absence of solvents by employing selected chromium and titanium-containing catalysts under specific operating conditions in a fluid bed process. Polyethylene products of those original processes exhibited medium-to-broad molecular weight distribution. To be commercially useful in the gas phase fluid bed process, or a slurry reactor process, undertaken at low pressures, e.g. of less than about 1000 psi, the catalyst must exhibit high activity, with concomittant high catalyst productivity, because these process systems do not include catalyst residue removal procedures. Accordingly, catalyst residue in the polymer product must be so small that it can be left in the polymer without causing any undue problems in the fabrication and/or to the ultimate consumer. To this end, the patent literature is replete with developments of new catalysts.
The use of metallocene compounds of transition metals as catalysts for polymerization and copolymerization of ethylene is one of those developments. Metallocenes can be described by the empirical formula Cp.sub.m MA.sub.n B.sub.p. These compounds in combination with alumoxane have been used to produce olefin polymers and copolymers, such as ethylene and propylene homopolymers, ethylene-butene and ethylene-hexene copolymers, e.g., Kaminsky et al, U.S. Pat. No. 4,542,199 and Sinn et al, U.S. Pat. No. 4,404,344.
Methylalumoxane (MAO) is used as co-catalyst with metallocene catalysts. It belongs to the class of alumoxanes which comprises oligomeric linear and/or cyclic alkylalumoxanes represented by the formula: R--(Al(R)--O).sub.n --AlR.sub.2 for oligomeric, linear alumoxanes and (--Al(R)--O--).sub.m for oligomeric cyclic alumoxane wherein n is 1-40, preferably 10-20, m is 3-40, preferably 3-20 and R is a C.sub.1 -C.sub.8 alkyl group and preferably methyl. Methylalumoxane is commonly produced by reacting trimethylaluminum with water or with hydrated inorganic salts, such as CuSO.sub.4 5H.sub.2 O or Al.sub.2 (SO.sub.4).sub.3.5H.sub.2 O. Methylalumoxane can be also generated in situ in polymerization reactors by adding to them trimethylaluminum and water or water-containing inorganic salts. MAO is a mixture of oligomers with a very wide distribution of molecular weights and usually with an average molecular weight of about 1200. MAO is typically kept in solution in toluene. While the MAO solutions remain liquid at fluid bed reactor temperatures, the MAO itself is a solid at room temperature.
Most of the experiments reported in the literature relating to methylalumoxane used as a cocatalyst with metallocene catalysts are undertaken in a slurry or solution process, rather than in a gas phase fluid bed reactor process.

Cofeeds of electron donating and electron withdrawing reagents to control MW in olefin polymerization using supported metallocene catalyst