In the present invention parapox genomes were screened using a novel expression strategy to test genes for dendritic cell recruitment activity. One gene was identified, designated as B2WL, that induces dendritic cell accumulation when expressed in skin. In additional testing a second gene, PP30, was identified that exhibited adjuvant activity in the absence of stimulating dendritic cell accumulation at the site of inoculation. When co-inoculated with an antigen-encoding plasmid, both genes acted as adjuvants in stimulating an antibody response to antigens. Furthermore, nucleic acids encoding the identified B2WL peptide adjuvant enhanced the level of protection against viral infection provided by immunization with an HA-expression plasmid. Thus, novel adjuvants for genetic immunization are identified. The invention also demonstrates the application of the linear expression element (LEE) technology for screening genomes of pathogens that may contain genes that are useful when expressed and tested in a novel context.

1. Field of the Invention
The present invention relates generally to the fields of immunopreventive therapy and vaccine development. More particularly, it concerns the development of novel polypeptides and nucleic acids encoding such polypeptides that can be used to initiate, stimulate, and/or enhance an immune response. These polypeptides and nucleic acids encoding them can be used as adjuvants that can be used to generate more potent and robust vaccines against desired polypeptides. Additionally, these polypeptides and nucleic acids can be used to initiate or enhance an innate immune response in a subject.
The application also describes the use of dendritic cell recruitment using a novel strategy.
2. Description of Related Art
Many methodologies of medical treatment can be envisioned that will require or benefit from an ability to initiate, stimulate, and/or enhance an immune response. These methodologies include those depending upon the creation of an immune response against a desired antigenic polypeptide and those that depend upon the initiation or modulation of an innate immune response.
The use of adjuvants for immunization are well known in the art however, the challenge of developing safe and effective adjuvants is ongoing. A primary disadvantage with current adjuvants is that most are unsuitable for use in human vaccines, including especially genetic vaccines.
One of the first adjuvant developed was Freund""s complete adjuvant. This adjuvant has excellent immunopotentiating properties, however, its side effects are so severe that it renders the use of this adjuvant unacceptable in humans, and sometimes in animals. Other oil emulsions adjuvants such as Incomplete Freund""s Adjuvant (IFA); Montanide ISA (incomplete seppic adjuvant); Ribi Adjuvant System (RAS); TiterMax; and Syntex Adjuvant Formulation (SAF) are also associated with various side effects such as toxicity and inflammation. Oil based adjuvants in general are less desirable in genetic immunization; they create side effects such as visceral adhesions and melanized granuloma formations, and they cannot form a homogeneous mixture with DNA preparations such as DNA-based vaccines.
Bacterially derived adjuvants, such as MDP and lipid A are also associated with undesirable side effects. Bacterial products such as Bordetella pertussis, Corynebacterium granulosum derived P40 component, Lipopolysaccharide (LPS), Mycobacterium and its components, and Cholera toxin, are another preferred group of adjuvants however, although they may augment the immune response to other antigens they are associated with side effects such as epilepsy as in the case of B. pertussis, and varying levels of toxicity.
Mineral compounds which include aluminum phosphate or aluminum hydroxide (alum) and calcium phosphate as adjuvants may also be employed. Aluminum salt-based adjuvants (such as alum) have excellent safety records but poor efficacy with some antigens (Sjolander et al., 1998). They are the most frequently used adjuvants for vaccine antigen delivery presently. Aluminum salt-based adjuvants are generally weaker adjuvants than emulsion adjuvants. The most widely used is the antigen solution mixed form with pre-formed aluminum phosphate or aluminum hydroxide however, these vaccines are difficult to manufacture in a physico-chemically reproducible way which results in batch to batch variation of the vaccine. When used in large quantity an inflammatory reaction may occur at the site of injection which is generally resolved in a few week although chronic granulomas may occasionally form.
Other available adjuvants, are know to those skilled in the art. One such adjuvant include liposomes. Although liposomes show favorable characteristics for use in bulk vaccine preparations, the preparation proves to be rather complex for use with occasional antigens prepared for injection especially when the antigen is available in limited quantity. GerbuR adjuvant, an aqueous phase adjuvant although associated with minimal inflammatory effects may require frequent boosting to maintain high titer. Squalene also included in the group of adjuvants have been associated with the Gulf War Syndrome and include such side effects as arthritis, fibromayalgia, rashes, chronic headaches, sclerosis and non healing skin lesions to name a few.
Various polysaccharide adjuvants are also known to those skilled in the art. For example, Yin et al., (1989) describe the use of various pneumococcal polysaccharide adjuvants on the antibody responses of mice. The doses that produce optimal responses, or that otherwise do not produce suppression, as indicated in Yin et al., (1989) should be employed. Polyamine varieties of polysaccharides are particularly preferred, such as chitin and chitosan, including deacetylated chitin.
One approach to circumvent the challenges of adjuvants entails the pox viruses. Pox viruses belong to a diverse family of viruses that can affect both humans and animals. Parapoxviruses are one member of this family that is known to affect humans, and is of special interest dermatologically since they are epitheliotropic (Diven, 2001). Parapoxvirus ovis is a 150 kb double-stranded DNA virus that causes skin pock lesions in susceptible animals. Transmittance of this viral infection, though mainly affecting sheep and cattle, can occur in human handling infected animals (Johannessen et al, 1975). The infection begins at a break in the skin or inflamed hair follicle and is completely resolved in 4-6 weeks though generally no specific immune response is induced. Therefore, the caveat of this viral infection is that the animal or individual can be re-infected with no enhancement of resolution of the individual lesions in subsequent infections (McKeever et al, 1988). Furthermore, specific immunity to parapox is not acquired and proves to be a challenge since no parapox-based vaccine is available.
Live vaccines can be problematic in their own way, however. Even they can fail to shield against some diseases. Those that work can cause full-blown illness in people whose immune system is compromised, as in cancer patients undergoing chemotherapy, AIDS sufferers and the elderly. Such individuals may also contract disease from healthy people who have been inoculated recently. Moreover, weakened viruses can at times mutate in ways that restore virulence, as has happened in some monkeys given an attenuated simian form of HIV, the virus that causes AIDS. For some diseases, the risks of reversion to virulence are intolerable.
Hence, more effective adjuvants are needed that will enhance the immune response induced by gene vaccines. In order to develop such strategies there is a need to identify factors that are directly able to interact with the immune system as in the natural viral infection of parapox, thereby allowing for the identification of potential new adjuvants for genetic immunization.
The present invention overcomes the deficiencies in the art by identifying polypeptides that are useful in modulating immune responses and nucleic acid sequences that encode such polypeptides. For example, the applicants have identified specific parapox genetic sequences that can be employed in these manners.
In general embodiments the present invention provides a method of stimulating the immune system of a subject, comprising introducing an immunostimulatory polypeptide from Parapox virus into the subject. In a preferred embodiment, the polypeptide is a polypeptide of Parapox virus strain D1701 or NZ2. In further embodiments the polypeptide has a an amino acid sequence of SEQ ID NO: 2, SEQ ID NO: 4, or SEQ ID NO: 6. In still yet a further embodiments the polypeptide is a B2WL polypeptide or a PP30 polypeptide.
In preferred embodiments, introducing the polypeptide into the subject comprises introducing a nucleic acid encoding the polypeptide into the subject. In specific embodiments, the nucleic acid encodes the polypeptide of Parapox virus strain D1701 or NZ2. In still yet a further embodiment, the nucleic acid encoding the polypeptide, has a nucleic acid sequence of SEQ ID NO: 1, SEQ ID NO. 3, or SEQ ID NO: 5. In another embodiment the nucleic acid encoding the polypeptide, is a nucleic acid encoding a B2WL or a PP30 polypeptide.
Additionally, the present invention provides a nucleic acid comprised in an expression vector. In some embodiments, the expression vector is a linear or circular expression element, a plasmid vector, or a viral vector. The invention further contemplates the administration of the nucleic acid orally, by inhalation, or by injection into the subject. Further, the nucleic acid is injected via microprojectile bombardment.
In providing a method of stimulating the immune system of a subject, comprising introducing an immunostimulatory polypeptide from Parapox virus into the subject, the present invention further provides a method of stimulating, initiating or enhancing an innate immune response in the subject. In further embodiments, the immunostimulatory polypeptide is employed as an adjuvant to initiate stimulate, or enhance an immune response to a second polypeptide against which an immune response is desired. The invention further contemplates introducing a second polypeptide into the subject. In still yet another embodiment, the invention provides a method of introducing the second polypeptide into the subject comprising introducing a nucleic acid encoding the second polypeptide into the subject. The invention further embodies a method of genetic immunization, and a method of producing antibodies against the second polypeptide.
The nucleic acid encoding the second polypeptide against which an immune response is desired is comprised in a vector which further comprises a nucleic acid encoding the polypeptide adjuvant. The invention embodies a vector such as a linear or circular expression element, a plasmid vector, or a viral vector.
The invention embodies a method of genetic immunization further comprising enhancing an immune response in the subject such as a mammal. In another embodiment a mammal is a human or a mouse.
A method of genetic immunization comprising introducing into the subject a nucleic acid segment encoding a Parapox immunostimulatory polypeptide and a nucleic acid segment encoding a second polypeptide against which an immune response is desired is provided in the present invention. The protein expressed from the polypeptide is an immunostimulatory polypeptide having an amino acid sequence of SEQ ID NO: 2, SEQ ID NO: 4, or SEQ ID NO: 6, and the nucleic acid segment having a sequence of SEQ ID NO: 1, SEQ ID NO: 3, or SEQ ID NO: 5. The protein expressed from the polypeptide is a B2WL or PP30 polypeptide further defined as an immunostimulant.
The nucleic acid segment encoding the polypeptide adjuvant is comprised in a vector such as a linear or circular expression element, a plasmid vector or a viral vector. The invention further contemplates administering a nucleic acid segment encoding the polypeptide adjuvant orally, by inhalation, or by injection. The nucleic acid segment encoding the polypeptide adjuvant is injected via microprojectile bombardment.
The nucleic acid segment encoding the second polypeptide is comprised in a vector which further comprises the nucleic acid segment encoding the immunostimulatory polypeptide. The vector of the present invention further embodies a linear or circular expression element, a plasmid vector or a viral vector. The vector comprising the second polypeptide is administered orally, by inhalation, or by injection into the subject. The vector comprising the second polypeptide is injected via microprojectile bombardment.
The invention further provides a subject such as a mammal which is further defined as a human or a mouse. In a general embodiment the invention further comprising immunizing the subject.
In a particular embodiment the invention provides a construct comprising a nucleic acid encoding a Parapox immunostimulatory polypeptide such as a polypeptide of Parapox strain D1701 or NZ2. In a particular embodiment, the construct has a sequence of SEQ ID NO: 2, SEQ ID NO: 4, or SEQ ID NO: 6, and the nucleic acid sequence of SEQ ID NO: 1, SEQ ID NO: 3 or SEQ ID NO: 5. In yet another particular embodiment, the Parapox immunostimulatory polypeptide is a B2WL or PP30 polypeptide.
The construct is further defined as encoding a second polypeptide against which an immune response is desired.
In a particular embodiment the construct is further defined as a vector. The construct is further defined as a linear or circular expression element, as a plasmid vector, or as a viral vector.
In a particular embodiment the invention provides a method of initiating dendritic cell accumulation with an immunostimulatory polypeptide from parapox virus, at the site of inoculation. This method is further defined as a method for treating a subject and as a method for in vitro purification.

Nucleic acid and polypeptide sequences useful as adjuvants

Board of Regents, The University of Texas System


This document discusses, among other things, a system and method for a coil having a plurality of resonant elements and an adjustable frame. A position of at least one resonant element can be adjusted relative to at least one other resonant element. A variable impedance is coupled to adjacent resonant elements and the impedance varies as a function of a separation distance. Cables are coupled to each resonant element and are gathered at a junction in a particular manner.

Magnetic resonance imaging and magnetic resonance spectroscopy involve providing an excitation signal to a specimen and detecting a response signal. The excitation signal is delivered by a transmit coil and the response is detected by a receive coil. In some examples, a single structure is used to both transmit the excitation signal and to receive the response.
Known devices and methods are inadequate.

Spatially reconfigurable magnetic resonance coil


MOS transistors having localized stressors for improving carrier mobility are provided. Embodiments of the invention comprise a gate electrode formed over a substrate, a carrier channel region in the substrate under the gate electrode, and source/drain regions on either side of the carrier channel region. The source/drain regions include an embedded stressor having a lattice spacing different from the substrate. In a preferred embodiment, the substrate is silicon and the embedded stressor is SiGe or SiC. An epitaxy process that includes using HCl gas selectively forms a stressor layer within the crystalline source/drain regions and not on polycrystalline regions of the structure. A preferred epitaxy process dispenses with the source/drain hard mask required of conventional methods. The embedded SiGe stressor applies a compressive strain to a transistor channel region. In another embodiment, the embedded stressor comprises SiC, and it applies a tensile strain to the transistor channel region.

The continued development of metal-oxide-semiconductor field-effect transistors (MOSFET) has improved the speed, density, and cost per unit function of integrated circuits. One way to improve transistor performance is through selective application of stress to the transistor channel region. Stress distorts or strains the semiconductor crystal lattice, which affects the band alignment and charge transport properties of the semiconductor. By controlling the magnitude and distribution of stress in a finished device, manufacturers can increase carrier mobility and improve device performance. There are several existing approaches of introducing stress in the transistor channel region.
One conventional approach includes forming an epitaxial, strained silicon layer on a relaxed silicon germanium (SiGe) layer. Since the SiGe lattice is larger than Si, the SiGe layer stretches the epi-layer in the lateral direction, i.e., the silicon will be under a biaxial tensile stress. Such a stress applied to a MOS channel region is particularly effective in improving N-channel transistor performance.
With a PMOS device, a tensile stress improves performance when it is perpendicular to the channel, but it has nearly the opposite effect when it is parallel to the channel. Unlike an N-channel transistor, when a biaxial, tensile stress is applied to a PMOS channel, the two stress effects almost cancel each other out. Improved PMOS fabrication therefore includes using substrate structures that apply a compression stress to the channel. One PMOS method includes selective application of a SiGe layer within the source/drain regions.
A problem with the prior art is that the new materials and methods required of strain-engineered devices creates significant process integration issues. For example, a silicon nitride tensile film formed over a NMOS transistor may be used to improve carrier mobility. For PMOS devices, on the other hand, an embedded SiGe stressor may be formed in a silicon substrate. A problem with these approaches, however, is that using different materials at different stages of the fabrication process further complicates an already complex process. Therefore, there remains a need for using strain engineering to improve device performance without significantly adding to the cost or complexity of the manufacturing process.

SiGe selective growth without a hard mask

Taiwan Semiconductor Manufacturing Company, Ltd.


Generally, existing LED lamps often use robust metallic cases since each of the cases functions as a heat sink. Various shapes for increasing the heat dissipation properties of the case have been employed; there is no unified shape. Existing LED lamps therefore have a problem that they cannot be easily disassembled at the time of recycling. Thus, an object is to provide a lamp which can be easily disassembled at the time of recycling. A lamp includes: a case having a certain shape; an LED module including a semiconductor light-emitting device; and a power supply circuit provided inside the case, for driving the semiconductor light-emitting device to emit light, wherein on an outer side of the case, a step for splitting the case is formed.

In recent years, lamps including semiconductor light-emitting devices such as Light-Emitting Diodes (LEDs) (hereinafter referred to as "LED lamps") have been increasingly used as lamps which would replace existing incandescent lamp bulbs or halogen lamp bulbs since these LED lamps have higher efficiency and longer operating life than the incandescent lamp bulbs or halogen lamp bulbs. In such a situation, more LED lamps are expected to be discarded in the future, and it is therefore important to efficiently recycle various resources included in the LED lamps.
For example, it is preferable to collect and recycle rare metals, such as gold or platinum, or heavy metals, such as gallium, included in components of the LED lamps. Since the LED lamps use a larger number of components than the existing incandescent lamp bulbs or halogen lamp bulbs, the effect of recycling of the LED lamps is high.
In order to efficiently recycle the LED lamps, the components included in the LED lamps need to be taken out. It is therefore preferred that the LED lamps can be relatively easily disassembled at the time of recycling.
In the field of general home appliances, various techniques for facilitating the disassembling at the time of recycling have been proposed (see PTL 1, for example). PTL 1 discloses a technique which facilitates the disassembling by using an engaging claw and a smaller number of screws.


An air control system (33) for an exhaust system (32) of a commercial or institutional kitchen (12) of a facility (10) in which the volume rate of air exhausted may be increased to improve the comfort, health, and safety conditions in the kitchen (12) and the rest of the facility (10). Comfort, health or safety may be determined by sensing a parameter in the ambient air environment (28), such as temperature and/or gas level. With the exhaust system (32) operating at a first volume rate to handle the activity of the cooking units 18, the air control system (33) causes exhaust system (32) to increase the volume rate toward a second, higher volume rate to exhaust more air from the ambient air environment (28) thereby reducing the temperature or gas level in the facility (10) to improve comfort and reduce load on a HVAC system (30) or to improve air quality which has health and safety benefits as well. Advantageously, the air control system (33) monitors exhaust temperature for an exceedance of a heat threshold, in which case fire control measures are taken.

The present invention relates to commercial and institutional kitchen exhaust systems, and more particularly, to an exhaust rate control method and apparatus for such exhaust systems.
Commercial and institutional kitchens are equipped to prepare food for large numbers of people and may form part of or adjoin larger facilities such as restaurants, hospitals and the like. Such kitchens are typically equipped with one or more commercial duty cooking units capable of cooking large amounts of food. On such a scale, the cooking process may generate substantial amounts of cooking heat and airborne cooking by-products such as water vapor, grease particulates, smoke and aerosols, all of which must be exhausted from the kitchen so as not to foul the environment of the facility. To this end, large exhaust hoods are usually provided over the cooking units, with duct work connecting the hood to a motor driven exhaust fan located outside the facility such as on the roof or on the outside of an external wall. As the fan is rotated by the motor, air within the kitchen environment is drawn into the hood and exhausted to the outside atmosphere. In this way, cooking heat and cooking by-products generated by the cooking units follow an air flow path defined between the cooking units and outside through the hood to be exhausted from the kitchen before they escape into the main kitchen environment and perhaps into the rest of the facility.
In many conventional installations, the motor driving the exhaust fan rotates at a fixed speed. The exhaust fan thus rotates at a fixed speed as well and, therefore, tends to draw air through the hood at a constant or fixed volume rate. However, the amount of cooking heat and/or cooking by-products generated by the cooking units will vary widely over the course of the day. It has been the practice in such instances to select a speed for the fan that will cause the system to exhaust a fixed volume rate of air based on the level of cooking heat and/or cooking by-products expected to be generated during anticipated peak usage of the cooking units. If the volume rate selected is too low, there will be times when the quantity of cooking by-products being generated exceeds the exhaust rate of the exhaust system. In such circumstances, the system will be in a relative underexhaust state such that cooking by-products will be released into the kitchen. The fixed volume rate is thus selected to be sufficiently large that under most normal operating situations, all of the cooking by products, for example, will be expelled out of the hood rather than released into the kitchen. As a consequence, during non-peak times, the exhaust fan is running faster than required so it tends to be in an overexhaust state wherein the volume rate of air being expelled is more than is necessary to clear the cooking by-products from the kitchen. In many exhaust conditions, as air is expelled through the hood, other air is drawn into the kitchen, such as from a make-up air system or the rest of the facility, which in turn draws in air from outside the facility. The heating, ventilating, and air conditioning ("HVAC") system of the facility must typically condition the drawn-in air. During overexhausting, the HVAC system may be heavily taxed to condition the drawn-in air. Thus, overexhausting has generally been recognized as uneconomical due to increased power usage by the exhaust system, reduced life of components such as the exhaust fan motor, and increased load on the HVAC system.
In order to prevent uneconomical overexhausting, I developed a system by which to vary the speed of the exhaust fan in accordance with the level of heat and/or by-products being generated by the cooking units. Such a system is described in my U.S. Pat. No. 4,903,685, the disclosure of which is hereby incorporated by reference in its entirety. In that system, when little or no cooking is occurring such that the level of heat, for example, being generated by the cooking units is extremely low, the speed of the fan is held low to expel air from the kitchen at a low volume rate. As cooking increases, the level of cooking heat also increases, and the speed of the fan is increased to increase the volume rate of air expelled from the hood to the outside. Consequently, the volume rate of air being expelled is generally proportional to the level of cooking heat being generated. The system may additionally, or alternatively, vary the volume rate in correlation to the level of cooking by-products being generated by the cooking units. In some situations, when any cooking by-product is detected, the exhaust volume rate may be forced to a high level, such as maximum, irrespective of the cooking heat level or variations in the level of cooking by-product. Varying the volume rate of air exhausted is expected to generally improve the energy efficiency of the facility. The foregoing notwithstanding, varying the volume rate solely based on the activity of the cooking units fails to account for opportunities to improve the comfort or enhance safety in the kitchen or other parts of the facility.
By way of example, there are typically substantial periods of time during which little or no cooking is being undertaken. During these idle times, the volume rate of air being exhausted will typically be quite low or even zero. Nonetheless, an ambient air environment away from the hood and air flow path but within the main area of the kitchen can still become quite hot. A typical HVAC system may require significant amounts of energy to cool the kitchen down to a more comfortable level and could also cause the rest of the facility to become uncomfortably cold. Conversely, as the HVAC system heats the facility, the kitchen may be caused to become uncomfortably hot. Similarly, the ambient air environment may become uncomfortable and/or unsafe due to build up of noxious gases or other harmful agents. For example, carbon dioxide may increase in the ambient air environment, particularly in the dining room, for example, due to the number of occupants of the facility. The above problems can also be encountered during non-idle times such that exhausting at a volume rate sufficient to exhaust cooking heat, for example, will not be sufficient to cool the kitchen or clear noxious gases.


A double talk detector for detecting double talk situations in a device capable of two-way voice communication. The double talk detector comprises means (2, I) for receiving a speech signal (3, 5; 30, 50), and means (82, 83) for dividing the speech signal (30, 50) into subsignals representing specific frequency bands. A detection is performed (84, 85, 86) for each subsignal, and subdecision signals are calculated (87) on the basis of the detection. The subdecision signals indicate existence of double talk in the respective subsignals. A final decision signal is calculated (89, 90, 91) as a double talk decision signal DTD for the speech signal on the basis of the subdecision signals.

Telephone communication is often disturbed by echo. This especially applies to full-duplex telephones which have four possible modes of operation: idle, near-speech, far-speech, and double-talk. Echo usually occurs in far-speech situations, when the received far-end signal reproduced by the speaker is caught by the microphone and thereby returns to far-end. A full-duplex telephone requires adaptive signal processing techniques to cancel acoustic feedback or echo. A known approach to avoid disturbing echo is to use an echo canceller or echo suppressor. Echo cancellers which are well known in the telephone communications environment usually employ a form of an adaptive digital filter. The echo canceller typically functions to disable the outgoing path from a phone when a signal from the far-end (speech received by the phone) appears on the incoming path. Therefore, echoes due to incoming signals on the receive path are prevented from returning to far-end over the outgoing path. Echo cancellation is usually implemented so that the parameters of the adaptive filter performing the echo cancellation are updated whenever far-end speech occurs in order to achieve echo cancellation as accurate as possible for each situation.
Double talking refers to the condition when the near end subscriber (the user of the phone) and the far-end subscriber talk simultaneously. When both parties talk simultaneously, i.e. during double talk, the echo canceller is no longer able to effectively block echo signals. This is because the echo signals are included in the near-end subscriber's signals to be transmitted, i.e. a desired signal to be transmitted and an echo signal are simultaneously applied to the send input. The super-positioning of these signals causes distortion of the adjustment of the echo canceller when it considers both the echo signal and the desired signal to be transmitted. This means that the replica produced by the echo canceller no longer sufficiently cancels the current echo signal. Accordingly, it is a current practice to provide a double talk detector for preventing the disturbing influence of double talk on echo canceller adjustment. This means that the parameters of the adaptive filter performing the echo cancellation are not updated during double talk. Echo and double talk are problems especially in speaker phones and in phones with hands-free equipment in which the far-end signal from the speaker is captured by the microphone.
Prior art echo suppressors include double talk detectors which distinguish between near-end speech, i.e. speech signals generated on the outgoing path by the near-end subscriber, and echo signals returning on the outgoing path due to far-end subscriber speech signals on the incoming path. If the outgoing path signal exceeds the incoming path signal it is assumed that the near-end subscriber is transmitting and the echo suppression is disabled. When the opposite condition occurs it is assumed that the near-end subscriber is not transmitting and the echo is suppressed.
FIG. 1 shows a block diagram of a phone comprising an echo canceller 1 known from prior art. The near-end signal 3 comes from the microphone 2 and is detected by a near-end voice activity detector 4 (VAD, Voice Activity Detector).
The far-end signal 5 comes from an input connection I of the phone (e.g. wire connection in wire phones and from air interface/antenna to reception branch in a mobile phone) and is detected by a far-end voice activity detector 6 and is finally output by the speaker 7. Both near-end signal 3 and far-end signal 5 are fed to a double talk detector 8 for double talk detection and to an adaptive filter 9 for performing echo cancelling. The adaptive filter 9 also receives the output of the double talk detector 8 in order to avoid adaptation of the filter during double talk. The adaptive filter 9 outputs a signal 10 which is subtracted from the near-end signal 3 in a summing/subtracting means 11 for cancelling echo and getting an echo cancelled output signal 12, which is forwarded to output connection 0 (e.g. wire connection in wire phones and from transmission branch to air interface/antenna in a mobile phone). The operation principle used is that the double-talk detector 8 needs the information of far-end speaker active and so it works only when there is far-end speech 5 and it is quite easy to detect if there is only far-end 5 or only near-end 3 speech. The adaptive filter 9 is controlled by double-talk, near-end and far-end detectors 8, 4 and 6. If there is double-talk, the coefficients of the adaptive filter 9 are frozen. The device of FIG. 1 could as well be a hands-free equipment with speaker, microphone, input and output connectors to a telephone device and the echo canceller situated in the hands-free device.
In European patent publication EP-B1-0 053 202 double talk detection is based on three detectors. A first detector compares the amplitude of the near-end signal before adaptation with the amplitude of the near-end signal after adaptation resulting in a first amplitude ratio. A second detector compares the amplitude of the near-end signal with the amplitude of the far-end signal resulting in a second amplitude ratio and a third detector compares the amplitude of the near-end signal before adaptation with the amplitude of the far-end signal resulting in a third amplitude ratio. The outputs of each detector are combined to make a common decision. The outputs are the above mentioned amplitude ratios taken over the entire frequency band. A drawback of this solution is that the result of adaptation affects the double talk detection so that actually a reliable detection is achieved only when the adaptation is false.
European patent publication EP-A2-0 439 139 discloses a double talk detector in which detection is based both on a cross-correlation value between the incoming signal and the echo signal and on a power ratio between the same signals. The power ratio is calculated over the entire frequency band. A drawback of this solution is that the changes of the cross-correlation value are slow, which makes double talk detection slow. The cross-correlation value is an average over several speech frames. The faster the double talk detection is the faster the adaptation (of the filter performing the echo suppression) can be stopped and false adaptation can be avoided. Likewise, when double talk detection is slow more false adaptation occurs.
European patent publication EP-A1-0 454 242 discloses an echo canceller in which double talk detection is performed by dividing the frequency band into narrower bands, i.e. into sub-channels. Then double talk detection is done separately for each sub-channel on the basis of the power ratio of a receive input signal and a send output signal. The detection result of each sub-channel is used only for adjustment of the adaptation of the same sub-channel in question. A drawback of this solution is that because the results are interpreted separately, a false echo cancellation result may be achieved if all sub-channels having double talk are not detected. Even if adaptation is stopped for a sub-channel in which double talk was detected a possibility exists that in a nearby sub-channel double talk exists as well, for which channel adaptation is, however, still performed because the double talk was not detected. That would lead to adaptation of the filter parameters for that sub-channel during double talk, which is not desired.

Double talk detector, method for double talk detection and device incorporating such a detector


A new cultivar of Bracteantha particularly characterized by a medium-early flowering response, shiny, dark-orange flowers, a rounded, bushy, upright plant habit with good growth and branching and a good production of cuttings, is disclosed.

The present invention comprises a new and distinct cultivar of Bracteantha, botanically known as Bracteantha bracteata, and hereinafter referred to by the cultivar name 'KLEBB07391'. 'KLEBB07391' was discovered as a seedling resulting from a cross in summer 2003 in Stuttgart, Germany between the proprietary female Bracteantha parent, 'BV 123' (unpatented) and the male parent, an unnamed typical individual plant of Bracteantha (unpatented). A single plant selection was subsequently chosen for further evaluation and for asexual propagation.
The new cultivar was created in 2003 in Stuttgart, Germany and has been asexually reproduced repeatedly by vegetative cuttings in Stuttgart, Germany over a three and one-half-year period. 'KLEBB07391' has been found to retain its distinctive characteristics through successive asexual propagations.


A system and method for enhanced cell detection by a User Equipment (UE) is provided. The UE includes a transceiver configured to receive a discovery reference signal (DRS) occasion from at least one transmission point. The DRS occasion comprising a set of consecutive DRS sub-frames. The UE also includes processing circuitry configured to: in response to detecting a physical cell identity (PCID) of a Primary Synchronization Signal (PSS)/Secondary Synchronization Signal (SSS)/Cell-Specific Reference Signal (CRS) that is the same as a reference PCID for a configured Channel State Information-Reference Signal (CSI-RS) resource, the processing circuitry attempts to detect or measure the CSI-RS using the timing obtained from the PSS/SSS/CRS; and in response to not detecting a PCID of PSS/SSS/CRS that is the same as the reference PCID for a configured CSI-RS resource (TP), the processing circuitry does not attempt to detect or measure the CSI-RS.

In certain wireless communications systems, a user equipment (UE) initiates cell search by scanning for Primary Synchronization Signals (PSS) and then Secondary Synchronization Signals (SSS) to identify a set of candidate cell identities (cell ID). Given a candidate cell ID, the UE then attempts to detect and measure the Cell-Specific Reference Signals (CRS) of the candidate cell. If the signal quality (signal power, Reference Signal Received Power (RSRP)) of the cell meets a certain criteria, the UE attempts to access the cell or if the UE has already connected to a serving cell, the UE may report its measurement result as well as the identity of the cell to the network.

Methods and apparatus for discovery signals for LTE advanced


A combination magnifier and illuminator comprised of a rigid rectangular housing that encloses a swing out lens retaining frame. The lens is a fresnel type which is very thin in nature that allows the entire thickness of the present invention to be less than one quarter of an inch thick. An ultra light white LED automatically turns on when the user swings out the magnifying lens allowing the user to see items such as a map or menu in low light conditions. The LED is powered by a button type battery that is housed in the circular space located at the pivot point of the swing out magnifier frame.

This invention relates generally to the field of reading aids, and more particularly to a combination magnifier and illuminator.
Magnifying devices have been in existence for hundreds of years. Illuminating devices such as electric lightbulbs have been in existence for over one hundred years. More recently small lamps called light diodes or LED""s have been developed which emit light while using very little electrical power. Most recently, a high powered white LED has been developed which can allow a person to see and read under very low light conditions. Additionally, a new type of magnifying lens called a fresnel lens has been developed and in use for the last thirty years. A fresnel lens is molded of clear plastic and, because of its concentricly ridged design, is very flat compared to typical glass or plastic lenses.
Products have been developed that have combined a typical magnifier lens with a lighting element so that a person can more clearly see a map or menu or the like under low light conditions.
However, the prior designs use standard magnifier elements and therefore tend to be somewhat thick in cross section. Although some of these units can fit in ones pocket, they are not as thin and inconspicuous when stored as they could be.
The primary object of the invention is to provide a combination magnifier and illuminator that fits easily into a persons pocket.
Another object of the invention is to provide a combination magnifier and illuminator that is very slim in overall thickness.
Another object of the invention is to provide a combination magnifier and illuminator where said illuminator automatically turns on when the magnifier portion is pulled out.
A further object of the invention is to provide a combination magnifier and illuminator where the housing includes a recessed portion that can receive a custom decorative element.
Other objects and advantages of the present invention will become apparent from the following descriptions, taken in connection with the accompanying drawings, wherein, by way of illustration and example, an embodiment of the present invention is disclosed.
The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention.


The inventive subject matter describes systems and methods for the implementation of an aquatic acoustical barrier, the aquatic acoustical barrier having a multiplicity of acoustical layers, the acoustical layers further having a multiplicity of acoustical leafs, such that when the acoustical barrier surrounds a noise source in the water there is an attenuation created by the noise source.

The present inventive subject matter relates to the systems and methods Systems and Methods for the Reduction of Underwater Acoustical Noise
The protection and preservation of natural resources includes the management of fish and game. Fish move about lakes, rivers, streams and reservoirs for a variety of reasons, including migration, spawning, and searching for food. Furthermore, some fish species have such small populations that they are protected either under State or Federal laws (e.g. the endangered species act).
During the construction of roads it is sometimes necessary to drive pilings or other support structures into lakes, streams, and/or marshes. The driving of these pilings or other structures into the water creates acoustical vibrations. These vibrations can be of sufficient power to either injure or kill fish or other aquatic animals that are in the proximity to the vibrations. The issue of effect of sound underwater, known as bioacoustics, is of sufficient concern that the California Department of Transportation (Caltrans), the departments of transportation for Oregon and Washington, and the Federal Highways Administration have formed groups to study the impact on fisheries due to in-water pile driving.
Prior art acoustical mitigation devices include air bubble curtains, cofferdams, isolation casings, and cushion blocks. Air bubble curtains employ a bubble screen to reduce sound pressure. The drawbacks for bubble screens are the limited reduction in acoustical pressure. Cofferdams have greater acoustical reduction, but, are expensive to install and remove. Isolation casings have the drawback of less attenuation than cofferdams. Lastly, cushion blocks are placed in-between the hammer and the pile (in the case of pile driving). Cushion blocks likewise have limited attenuation properties as compare to cofferdams.
Therefore, there is a need to have a aquatic acoustical barrier proximate to underwater construction in general and near pile driving in particular. This barrier should have low cost, use readily available materials, and be easy to install and extract, and provide limited damage to the water environment.

Systems and methods for the reduction of underwater acoustical noise


In a lithographic apparatus, a reference grating 11 mounted on the wafer table WT is illuminated with a measurement beam 20 incident in a direction independent of wafer table tilt. The diffraction orders are detected by detector 30 and used to determine the lateral shift in the wafer table resulting from a non-zero Abbe arm, and hence the Abbe arm, for calibration purposes. The detector 30 may be a detector also used for off-axis alignment of the wafer and wafer table.

1. Field of the Invention
The present invention relates to the calibration of the Abbe arm in lithographic apparatus. More particularly, the invention relates to a system for calibration of the Abbe arm in lithographic projection apparatus comprising:
an illumination system for supplying a projection beam of radiation;
a first object table for holding patterning means capable of patterning the projection beam according to a desired pattern;
a second object table for holding a substrate;
a projection system for imaging the patterned beam onto a target portion of the substrate; and
a positioning system for moving said second object table between an exposure position, at which said projection system can image said mask portion onto said substrate, and a measurement position.
2. Description of the Related Art
The term xe2x80x9cpatterning meansxe2x80x9d should be broadly interpreted as referring to means that can be used to endow an incoming radiation beam with a patterned cross-section, corresponding to a pattern that is to be created in a target portion of the substrate; the term xe2x80x9clight valvexe2x80x9d has also been used in this context. Generally, the said pattern will correspond to a particular functional layer in a device being created in the target portion, such as an integrated circuit or other device (see below). Examples of such patterning means include:
A mask held by said first object table. The concept of a mask is well known in lithography, and its includes mask types such as binary, alternating phase-shift, and attenuated phase-shift, as well as various hybrid mask types. Placement of such a mask in the projection beam causes selective transmission (in the case of a transmissive mask) or reflection (in the case of a reflective mask) of the radiation impinging on the mask, according to the pattern on the mask. The first object table ensures that the mask can be held at a desired position in the incoming projection beam, and that it can be moved relative to the beam if so desired.
A programmable mirror array held by a structure, which is referred to as first object table. An example of such a device is a matrix-addressable surface having a viscoelastic control layer and a reflective surface. The basic principle behind such an apparatus is that (for example) addressed areas of the reflective surface reflect incident light as diffracted light, whereas unaddressed areas reflect incident light as undiffracted light. Using an appropriate filter, the said undiffracted light can be filtered out of the reflected beam, leaving only the diffracted light behind; in this manner, the beam becomes patterned according to the addressing pattern of the matrix-addressable surface. The required matrix addressing can be performed using suitable electronic means. More information on such mirror arrays can be gleaned, for example, from U.S. Pat. Nos. 5,296,891 and 5,523,193, which are incorporated herein by reference.
A programmable LCD array held by a structure, which is referred to as first object table. An example of such a construction is given in U.S. Pat. No. 5,229,872, which is incorporated herein by reference.
For purposes of simplicity, the rest of this text may, at certain locations, specifically direct itself to examples involving a mask; however, the general principles discussed in such instances should be seen in the broader context of the patterning means as hereabove set forth.
The projection system may hereinafter be referred to as the xe2x80x9clensxe2x80x9d; however, this term should be broadly interpreted as encompassing various types of projection system, including refractive optics, reflective optics, and catadioptric systems, for example. The illumination system may also include components operating according to any of these design types for directing, shaping or controlling the projection beam of radiation, and such components may also be referred to below, collectively or singularly, as a xe2x80x9clensxe2x80x9d. In addition, the first and second object tables may be referred to as the xe2x80x9cmask tablexe2x80x9d and the xe2x80x9csubstrate tablexe2x80x9d, respectively.
Lithographic projection apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In such a case, the patterning means may generate a circuit pattern corresponding to an individual layer of the IC, and this pattern can be imaged onto a target portion (comprising one or more dies) on a substrate (silicon wafer) that has been coated with a layer of radiation-sensitive material (resist). In general, a single wafer will contain a whole network of adjacent target portions that are successively irradiated via the projection system, one at a time. In current apparatus, employing patterning by a mask on a mask table, a distinction can be made between two different types of machine. In one type of lithographic projection apparatus, each target portion is irradiated by exposing the entire mask pattern onto the target portion at once; such an apparatus is commonly referred to as a wafer stepper. In an alternative apparatusxe2x80x94commonly referred to as a step-and-scan apparatusxe2x80x94each target portion is irradiated by progressively scanning the mask pattern under the projection beam in a given reference direction (the xe2x80x9cscanningxe2x80x9d direction) while synchronously scanning the substrate table parallel or anti-parallel to this direction; since, in general, the projection system will have a magnification factor M (generally  less than 1), the speed V at which the substrate table is scanned will be a factor M times that at which the mask table is scanned. More information with regard to lithographic devices as here described can be gleaned, for example, from U.S. Pat. No. 6,046,792, incorporated herein by reference.
In general, apparatus of this type contained a single first object (mask) table and a single second object (substrate) table. However, machines are becoming available in which there are at least two independently movable substrate tables; see, for example, the multi-stage apparatus described in U.S. Pat. No. 5,969,441 and U.S. application Ser. No. 09/180,011, filed Feb. 27, 1998 (WO 98/40791), incorporated herein by reference. The basic operating principle behind such a multi-stage apparatus is that, while a first substrate table is underneath the projection system so as to allow exposure of a first substrate located on that table, a second substrate table can run to a loading position, discharge an exposed substrate, pick up a new substrate, perform some initial metrology steps on the new substrate, and then stand by to transfer this new substrate to the exposure position underneath the projection system as soon as exposure of the first substrate is completed, whence the cycle repeats itself; in this manner, it is possible to achieve a substantially increased machine throughout, which in turn improves the cost of ownership of the machine.
The measurement performed on the substrate at the measurement position may, for example, include a determination of the spatial relationship (in X and Y directions) between various contemplated target areas on the substrate (die, areas) and a reference marker (e.g. fiducial) located on the second object table outside the area of the substrate. Such information can subsequently be employed at the exposure position to perform a fast and accurate leveling of the target areas with respect to the projection beam; for more information see WO 99/32940 (P-0079), for example. This document also describes the preparation at the measurement position of a height map relating the Z position of the substrate surface at an array of points to a reference plane of the second object table. However the reference plane is defined by a Z-interferometer at the measurement position and a different Z-interferometer is used at the at the exposure position. It IS therefore necessary to know accurately the relationship between the two Z-interferometers.
The so-called Abbe arms AAx, AAy in a lithograph device are the distances between the surface of the substrate, when mounted on the second object table, and the axes of rotation of the second object table in Rx and Ry. (In this document, R1 denotes rotation about an axis parallel to the I-direction in an orthogonal XYZ system, where the XY plane is parallel to the substrate surface at zero tilt.) These axes are fictitious and determined by software since, in general, the tilt of the second object table about the X and Y-axes is controlled by spaced-apart Z actuators rather than by rotating it about physical pivots.
The effect of a non-zero Abbe arm in the exposure position is illustrated in FIG. 2 of the accompanying drawings. As can there be seen, if the Abbe arm AAy, for example, is non-zero, rotation of the substrate W about the Y axis by an amount dRy causes a shift in the central focal point P of the projection lens system PL on the substrate by an amount dX. Correspondingly, rotation dRx causes a shift dY. For small angles of rotation the following equations hold:
dX≈dRyxc2x7AAyxe2x80x83xe2x80x83[1]
dY≈dRxxc2x7AAxxe2x80x83xe2x80x83[2]
The Abbe arms, AAx, AAy, may also conveniently be expressed in the form (Zw-Za), where Zw is the height of the surface of the substrate in the reference system of the apparatus and Za is the height of the relevant axis of rotation in that system.
Since the rotation-invariant point of the second object table is determined by software, referring to an interferometer system which measures the position of the second object table, it may be thought that there is no difficulty in setting the Abbe arm to zero. However, the high precision requirements on the Abbe arm and the irregularities that exist between interferometer systems make it necessary to calibrate the Abbe arm with very high accuracy on initial set-up. It can be necessary to repeat the calibration after set-up because of the occurrence of drift.
A known method of determining the Abbe arms at the exposure position for calibration purposes is to expose a substrate with a series of reference marks at various tilts of the second object table. After development of the substrate, measurement of the translation of the marks in X and Y for the different tilts enables the Abbe arms to be determined. Since the Abbe arm is effectively dependent on the interferometer system, calibrations have to be done at both the measurement and the exposure positions. However, the known method cannot be used at the measurement position as no exposure device is available there. The need to develop a substrate is also time consuming.
An object of the present invention is to provide a system for calibrating the Abbe arm in a lithographic projection apparatus that avoids or alleviates the disadvantages of the prior art.
According to the present invention there is provided a lithographic projection apparatus comprising:
an illumination system for supplying a projection beam of radiation;
a first object table for holding patterning means capable of patterning the projection beam according to a desired pattern;
a second object table for holding a substrate having a surface to be exposed, such that, when held on the table, the said surface lies in a reference plane;
a projection system for imaging the patterned beam onto a target portion of the substrate; and
a positioning system for moving said second object table between an exposure position, at which said projection system can image said patterned beam onto said substrate, and a measurement position; characterized by:
a calibration system for measuring lateral displacements of a reference point in a plane of said second object table as a function of tilt, at said measurement position, wherein said calibration system comprises:
a diffraction grating mounted to said second object table;
illuminating means for generating a measurement beam of radiation and directing it to be incident on said diffraction grating so as to be diffracted thereby; and
a detector for detecting the position of said diffraction grating.
By using a calibration system for measuring lateral displacements of a reference point in a plane of said second object table as a function of tilt, it is possible to measure the Abbe arm at the measurement position. Once the Abbe arm is measured it is possible to calibrate the Abbe arm to a predetermined vertical distance from the reference plane of the second object table. Advantageously this predetermined vertical distance is set to zero, such that no lateral displacement of a reference point in said reference plane will occur with tilt of the second object table.
Preferably, said diffraction grating is an at least partially transmissive diffraction grating and said calibration system comprises a light guide for directing said measurement beam to be incident on said diffraction grating in a direction substantially independent of the tilt of said second object table.
By use of a measurement beam having an angle of incidence independent of second object table tilt, the lateral shift of a reference grating with non-zero Abbe arm can be measured independently of, or separated from, the tilt dependence of the diffracted beams from the reference grating. This is necessary because, during set-up, a detector used to measure the position of the diffraction grating is not focused and therefore the measurement of the position of the grating will show a dependency on the angle of the diffracted beams. By using a measurement beam having an angle of incidence independent of second object table tilt, this problem is circumvented.
According to a further aspect of the present invention, there is provided a method of calibrating a lithographic projection apparatus comprising:
an illumination system for supplying a projection beam of radiation;
a first object table for holding patterning means capable of patterning the projection beam according to a desired pattern;
a second object table for holding a substrate having a surface to be exposed, such that, when held on the table, the said surface lies in a reference plane;
a projection system for imaging the patterned beam onto a target portion of the substrate; and
a positioning system for moving said second object table between an exposure position, at which said projection system can image said patterned beam onto said substrate, and a measurement position, said positioning system including electronic control means having parameters defining a rotation-invariant point of the second object table; the method comprising the steps of:
measuring the position of a reference point on the surface of the second object table at different tilts;
calculating the distance between the surface of the second object table and a rotation-invariant point of the second object table;
adjusting parameters of said electronic control means included in said positioning system so that said rotation-invariant point is at a predetermined vertical distance from the reference surface of the second object table.
According to a further aspect of the present invention there is provided a method of manufacturing a device using a lithographic projection apparatus comprising:
an illumination system for supplying a projection beam of radiation;
a first object table for holding patterning means capable of patterning the projection beam according to a desired pattern;
a second object table for holding a substrate having a surface to be exposed, such that, when held on the table, the said surface lies in a reference plane;
a projection system for imaging the patterned beam onto a target portion of the substrate; the method comprising the steps of:
providing a substrate provided with a radiation-sensitive later to said second object table;
providing a projection beam of radiation using the illumination system;
using said patterning means to endow the projection beam with a pattern in its cross section; and
moving the second object table to an exposure position, and projecting the patterned beam of radiation onto said target portions of the substrate; characterized by the step of:
detecting displacements of a reference point of said second object table at various angles of tilt when situated at said measurement position.
In a manufacturing process using a lithographic projection apparatus according to the invention a pattern in a mask is imaged onto a substrate which is at least partially covered by a layer of radiation-sensitive material (resist). Prior to this imaging step, the substrate may undergo various procedures, such as priming, resist coating and a soft bake. After exposure, the substrate may be subjected to other procedures, such as a post-exposure bake (PEB), development, a hard bake and measurement/inspection of the imaged features. This array of procedures is used as a basis to pattern an individual layer of a device, e.g. an IC. Such a patterned layer may then undergo various processes such as etching, ion-implantation (doping), metallization, oxidation, chemo-mechanical polishing, etc., all intended to finish off an individual layer. If several layers are required, then the whole procedure or a variant thereof, will have to be repeated for each new layer. Eventually, an array of devices will be present on the substrate (wafer). These devices are then separated from one another by a technique such as dicing or sawing, whence the individual devices can be mounted on a carrier, connected to pins, etc. Further information regarding such processes can be obtained, for example, from the book xe2x80x9cMicrochip Fabrication: A Practical Guide to Semiconductor Processingxe2x80x9d, Third Edition, by Peter van Zant, McGraw Hill Publishing Co., 1997, ISBN 0-07-067250-4.
Although specific reference mall be made in this text to the use of the apparatus according to the invention in the manufacture of ICs, it should be explicitly understood that such an apparatus has many other possible applications. For example, it may be employed in the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memories, liquid-crystal display panels, thin-film magnetic heads, etc. The skilled artisan will appreciate that, in the context of such alternative application any use of the terms xe2x80x9creticlexe2x80x9d, xe2x80x9cwaferxe2x80x9d or xe2x80x9cdiexe2x80x9d in this text should be considered as being replaced by the more general terms xe2x80x9cmaskxe2x80x9d, xe2x80x9csubstratexe2x80x9d and xe2x80x9ctarget areaxe2x80x9d, respectively.
In the present document, the terms xe2x80x9cradiationxe2x80x9d and xe2x80x9cbeamxe2x80x9d are used to encompass all types of electromagnetic radiation or particle flux, including, but not limited to, ultraviolet radiation (e.g. at a wavelength of 365 nm, 248 nm, 193 nm, 157 nm or 126 nm), EUV, X-rays, electrons and ions.

Abbe arm calibration system for use in lithographic apparatus


In a particular embodiment, a method is disclosed that includes automatically adding a first power line in a channel between at least two macros when less than two system power supply lines with opposite polarities are detected within the channel.

Complex application-specific integrated circuit (ASIC) and/or a system on a chip (SoC) designs use large numbers of hard macro cells, such as memory cells and/or mixed-signal devices. The macros are generally placed in clusters due to timing and/or physical constraints. The clustering of hard macro cells can be so large that signal delay on wire connections to, from and/or through the macro cell clusters becomes of concern for ASIC/SoC performance. Gaps between pairs of macro cells may be defined as channels when the gaps are smaller than certain threshold values. Buffering in the channels is an efficient way to speed up signals on wire connections. To enable buffering, the power grid integrity in the channels should be guaranteed. The power grid integrity in a channel may mean that there should be at least two power supply lines with opposite polarities (one power line and one ground line) existing in that channel. Typically, the size of the channels (width for vertical channels or height for horizontal channels) between the macro cells is not large enough to satisfy the power grid integrity requirement.
One conventional solution is to allocate larger channels to allow at least two power lines with opposite polarities to be present in the channels. However, this may lower the macro device placement density and therefore increase the size of the die chip, which increases the cost of the final products. Another conventional solution is to manually patch individual channels that are intended to be used. However, manual patching is a time-consuming, tedious and error-prone process, and the results may not be consistently repeatable.

This patent is subject to a terminal disclaimer.

Method to automatically add power line in channel between macros


A TOI LiDAR System generates an image of an object based on the distance of various point measurements to the object. The TOI LiDAR System detects the envelope of an electrical signal created from an interference light signal. The interference light signal is produced from the back-reflected light resulting from a sampling arm light emission to the object combined with a reference light emission. The reference light emission is created by splitting a pulse-modulated coherent light source's emission signal and passing the reference light emission through a reference arm. The optical interference signal is transferred to a balanced photodetector to convert to an electrical signal converted to digital data. The digital data is evaluated to determine the rising edges or falling edges of a digitized electrical interference signal to determine a time delay between the reference light emission and back-reflected light used to calculate the distance.

Light detection and ranging (LiDAR) is analogous to radio detection and ranging (Radar) in that LiDAR uses optical waves to determine the range, angle, and velocity of objects. LiDAR utilizes differences in laser light return times and wavelengths that can be used to make digital 3-D representations of the target and has been broadly used in terrestrial, airborne, and mobile applications. A LiDAR instrument consists of one or more laser emitters, optics, a scanner, a photodetector, and a signal processor. The one or more laser emitters generate a coherent light beam transferred through a set of optics to a scanner to be transmitted to an object for determining the distance to the object or the object's velocity. In the case of three-dimensional (3D) scanning, the physical features are determined. The photodetector receives the coherent light reflected from the object and converts the coherent light to electrical signals that are processed to determine the object's distance. The emitter will generate the coherent light as pulses. The signal processor records the time of the transmitted pulse, and the time of the reception of the reflection of the coherent light is recorded. The distance is the difference between the transmitted time and the received time divided by two and multiplied by the speed of light.
Amplitude modulation continuous wave (AMCW) LiDAR is a phase-based form of LiDAR. Unlike direct pulse detection, the phase-based LiDAR emits a continuous laser signal. It modulates the laser emission amplitude with a high-speed radiofrequency (RF) signal to encode the output optical signal. The phase difference between the emitted signal and the reflected signal is detected for ranging. The phase shift of a sinusoidally-modulated continuous laser waveform can be used to infer the distance to an object.
Frequency modulated continuous wave (FMCW) LiDAR is similar to AMCW LiDAR, but the modulation and demodulation are performed optically rather than electrically. FMCW LiDAR uses a wavelength-tuning light source or a phase-modulating light source and an interferometer to measure the object's distance with good sensitivity. "Comb-Calibrated Frequency-Modulated Continuous-wave LiDAR, "Y. Xie et al., 2020 IEEE 7th International Workshop on Metrology for AeroSpace (MetroAeroSpace), Pisa, Italy, 2020, pp. 372-376, Found Feb. 15, 2021 at URL: https://ieeexplore.ieee.org/stamp/stamp.jsp? tp=&arnumber=9160234&isnumber=9159966 describes FMCW LiDAR as very suitable for absolute distance measurement. The FMCW laser's frequency is linearly modulated by a carrier signal to accurately measure the laser round-trip flight time. The flight time can be calculated with high precision by detecting the beat frequency signal between the returned laser and the emitted laser. High-precision distance measurement can be achieved.
Time-of-interference (TOI) LiDAR technology is a new ranging method that overcomes limitations of traditional LiDAR techniques, including time-of-flight (ToF) and frequency-modulated continuous-wave (FWCW) with the following features: (1) utilization of an interferometer with balanced detector allowing highly sensitive detection of weak interference signals from long range; (2) time delay of the interference signal can be measured even when the signal frequency is high, and thus provides accurate measurement of the distance from the object, eliminating the need of high-speed data acquisition systems; (3) phase- or wavelength-modulation requirement of the light source is low and thus can simplify the complexity of the driver circuit design for the light source. The operating speed of TOI LiDAR systems is mainly limited by the modulation speed of the light source and the efficiency of the optical receiver.

High-speed time-of-interference light detection and ranging apparatus


A bottom-contact type organic thin film transistor comprising at least a gate electrode, an insulator layer, a source electrode, a drain electrode and an organic semiconductor layer, on a substrate, wherein at least one of the source electrode and the drain electrode has a multilayer structure formed by stacking an oxide layer and a metal layer, and the metal layer is surface-modified with an organic thin film layer.

Organic thin film transistors have lots of excellent features such as they can be produced by employing low-temperature film formation process, it is easy to form a film on a flexible and light-weight substrate made of resins or the like, and they are suited for inexpensive solution application processes, in compared with thin film transistors using the conventional inorganic silicon thin film. Their research and development are actively preceded as the core technology for next generation of flexible electronics.
FIG. 2 is an outline cross-sectional view of a top-contact type organic thin film transistor which has a representative structure of an organic thin film transistor (hereinafter often referred to simply as an "organic TFT").
The top-contact type organic TFT 2 has, on a substrate 10, a gate electrode 20, an insulator layer 30 and an organic semiconductor layer 40 in this sequence. A drain electrode 50 and a source electrode 60 are disposed on the organic semiconductor layer 40 with a predetermined distance (channel region 70).
Like the organic TFT 2, such a structure in which a source electrode 60 and a drain electrode 50 are arranged opposite a substrate 10 via an organic semiconductor layer 40 is particularly called as a top-contact type.
In the top-contact type organic TFT 2, the organic semiconductor layer 40 forms the channel region 70, and the flow of an electric current to the source electrode 60 and the drain electrode 50 can be controlled by the voltage applied to the gate electrode 20.
The top-contact type organic TFT 2 can be fabricated as follows: on the substrate 10 on which the gate electrode 20 and the insulator layer 30 are formed, the organic semiconductor layer 40 is formed by vacuum deposition or a solution process such as spin coating, dip coating or casting, and the source electrode 60 and the drain electrode 50 are formed by, for example, vacuum deposition using a deposition mask.
FIG. 3 is an outline cross-sectional view of a bottom-contact type organic TFT.
The bottom-contact type organic TFT 3 has, on a substrate 10, a gate electrode 20 and an insulator layer 30 in this sequence. A drain electrode 50 and a source electrode 60 are disposed on the insulator layer 30 with a predetermined distance (channel region 70), and an organic semiconductor layer 40 are further stacked on the drain electrode 50 and the source electrode 60 to cover these electrodes.
Like the organic TFT 3, such a structure in which the source electrode 60 and the drain electrode 50 are formed on the substrate, and the organic semiconductor layer 40 are stacked on the source electrode 60 and the drain electrode 50 is particularly called as a bottom-contact type.
In the bottom-contact type organic TFT 3, the gate electrode 20, the source electrode 60 and the drain electrode 50 form a circuit pattern on the substrate 10, and the organic semiconductor layer 40 is formed on the circuit pattern.
For forming an electrode, known photolithography and the like can be employed. Therefore, a circuit pattern having high-resolution and a large area can be easily formed. Thus, different from the top-contact type organic TFT, in the bottom-contact type organic TFT, the organic semiconductor layer is formed on the substrate on which the circuit pattern has been previously formed. As a result, the bottom-contact type organic TFT has the advantage that the organic semiconductor material constituting the organic semiconductor layer does not deteriorate due to the physical and chemical stresses associated with the formation of electrodes.
The bottom-contact type organic TFT has the above-mentioned advantages. However, there is a problem that the properties of the bottom-contact type organic TFT are significantly inferior to a top-contact type organic TFT fabricated using the same organic semiconductor material. It is considered that in the bottom-contact type organic TFT, a large contact resistance lies between the organic semiconductor layer and the electrodes.
To solve the problem, an approach to use a multilayer structure composed of an oxide layer/metal layer for the source-drain electrodes. Namely, this approach is aimed to lower the charge-injection barrier between the electrode layer and the organic semiconductor layer using materials having a good charge-injection property for the oxide layer.
Patent Document 1 discloses a TFT wherein source-drain electrodes contact with a p-type organic semiconductor via a charge-injecting layer formed of an inorganic substance, an oxide of molybdenum or vanadium is used for the charge-injecting layer, and the inorganic charge-injecting layer having a medium energy level is disposed between the channel and the source-drain electrodes.
The effects of this TFT include decrease of the driving voltage, stabilization of the properties and increase of the reliability.
Non-Patent Document 1 discloses a TFT which has a MoOx/Au electrode using MoOx in place of Cr or Ti generally used for a base layer for the Au electrode. Further, it describes that the thickness of the MoOx is preferably 2 nm.
This TFT can reduce the contact resistance between the source-drain electrodes and the organic semiconductor (pentacene) to decrease the voltage.
Different from the above-mentioned approach, an approach wherein a metal electrode is surface-modified with an organic compound having a thiol group at the terminal to form an organic thin film layer, thereby controlling the wettability of the surface of the metal electrode and the work function has been also made.
Patent Document 2 discloses a bottom-contact type TFT wherein a taper (incline) is provided with the edge portion of sourced-drain electrodes, the width of the taper is made to be smaller than the average particle diameter of semiconductor crystals, and an organic compound layer (1 Å to 10 Å) formed of a compound having a thiol group is disposed between the source-drain electrodes and the semiconductor layer.
In this TFT, the contact resistance of the interface of the source-drain electrodes/semiconductor is reduced to increase the performance.
Patent Document 3 discloses a TFT wherein thiocresol is disposed between the source-drain electrodes and the organic semiconductor film.
Patent Document 4 discloses a TFT wherein an electrode-surface treating agent having a functional group (for example, a thiol group) which forms a chemical bond with a metal is used.
This TFT has good TFT property, and solution processes which give high production efficiency can be employed.
Non-patent Document 2 discloses a TFT wherein an Au electrode is treated with a SAMs (self-assembled molecular film) such as decanethiol, CH3—(CH2)9—SH (DT), perfluorodecanethiol CF3—(CF2)7—(CH2)2—SH (PFDT) or perfluorohexanethiol CF3—(CF2)3—(CH2)2—SH (PFHT), to vary the work function so that charge injection from the electrode is improved.
In this TFT, for example, for the DT/Au electrode, the work function decreases by 0.45 eV, and for the PFDT/Au electrode, the work function increases by 0.9 eV. Accompanying thereto, the contact resistance increased in the case of the DT/Au electrode and decreased in the case of the PFDT/Au electrode, in comparison with the Au alone.
Non-patent Document 3 discloses a TFT wherein the hole-injection barrier is lowered by treating a Cr/Au electrode with 1-hexadecanethiol (CH3—(CH2)15—SH), and which has the following relationship:Ip:Au(5.1 ev)>Pentacene HOMO(5.0)>Au/C16H33SH(4.9).
Non-patent Document 4 discloses a TFT wherein a gold electrode is treated with pentafluorothiophenol (PFTP) to improve the contact between the electrode-semiconductor.
In spite of the above-mentioned approaches, the problems in the bottom-contact type organic TFT of high threshold voltage, low mobility and the like cannot be completely dissolved.
An object of the invention is to provide a bottom-contact type organic TFT having a low threshold voltage, a high field-effect mobility and a high on/off current ratio.


The present invention relates generally to the fields of molecular biology and protein technology. More specifically, the invention concerns signal sequences for the secretion of heterologous polypeptide from bacteria. The invention also concerns recombinant polypeptides and uses thereof.

Secretion of heterologous polypeptides into the periplasmic space of E. coli and other prokaryotes or into their culture media is subject to a variety of parameters. Typically, vectors for secretion of a polypeptide of interest are engineered to position DNA encoding a secretory signal sequence 5′ to the DNA encoding the polypeptide of interest.
Recent years have seen increasing promises of using heterologous polypeptide, for example, antibodies, as diagnostic and therapeutic agents for various disorders and diseases. Many research and clinical applications require large quantities of functional polypeptide, thus calling for scaled-up, yet economic systems for polypeptide production. Particularly useful is the recombinant production of antibodies using a variety of expression hosts, ranging from prokaryotes such as E. coli or B. subtilis, to yeast, plants, insect cells and mammalian cells. Kipriyanov and Little (1999) Mol. Biotech. 12:173-201.
Compared to other polypeptide production systems, bacteria, particularly E. coli, provides many unique advantages. The raw materials used (i.e. bacterial cells) are inexpensive and easy to grow, therefore reducing the cost of products. Prokaryotic hosts grow much faster than, e.g., mammalian cells, allowing quicker analysis of genetic manipulations. Shorter generation time and ease of scaling up also make bacterial fermentation a more attractive means for large quantity protein production. The genomic structure and biological activity of many bacterial species including E. coli have been well-studied and a wide range of suitable vectors are available, making expression of a desirable antibody more convenient. Compared with eukaryotes, fewer steps are involved in the production process, including the manipulation of recombinant genes, stable transformation of multiple copies into the host, expression induction and characterization of the products. Pluckthun and Pack (1997) Immunotech 3:83-105.
Various approaches have been used to make recombinant polypeptides in bacteria. Recombinant proteins can be obtained from bacteria either through refolding of inclusion bodies expressed in the cytoplasm, or through expression followed by secretion to the bacterial periplasm. The choice between secretion and refolding is generally guided by several considerations. Secretion is usually the faster and more commonly used strategy for producing antibodies. Kipriyanov and Little (1999), supra.
Antibody expression in prokaryotic systems can be carried out in different scales. The shake-flask cultures (in the 2-5 liter-range) typically generate less than 5 mg/liter products. Carter et al. (1992) Bio/Technology 10:12-16 developed a high cell-density fermentation system in which high-level expression (up to 2 g/liter) of antibody fragments was obtained. The gram per liter titers of Fab′ obtained by Carter et al. is due largely to higher cell densities resulting from the more precisely controlled environment of a fermentor than that of a simple shake flask. The system contains a dicistronic operon designed to co-express the light chain and heavy chain fragments. The dicistronic operon is under the control of a single E. coli phoA promoter which is inducible by phosphate starvation. Each antibody chain is preceded by the E. coli heat-stable enterotoxin II (stII) signal sequence to direct secretion to the periplasmic space.
For general reviews of antibody production in E. coli, see Pluckthun and Pack (1997) Immunotech 3:83-105; Pluckthun et al. (1996) in ANTIBODY ENGINEERING: A PRACTICAL APPROACH, pp 203-252 (Oxford Press); Pluckthun (1994) in HANDBOOK OF EXP PHARMCOL VOL 3: THE PHARMCOL OF MONOCLONAL ANTIBODIES, pp 269-315 (ed. M. Rosenberg and G.P. Moore; Springer-Verlag, Berlin).
Many biological assays (such as X-ray crystallography) and clinical applications (such as protein therapy) require large amounts of protein. Accordingly, a need exists for high yield yet simple systems for producing properly assembled, soluble and functional heterologous polypeptides, such as antibodies.
All references cited herein, including patent applications and publications, are incorporated by reference in their entirety.

Methods and composition for secretion of heterologous polypeptides


An image pickup apparatus photoelectrically converts image light from an object. The image light incident on the photosensing plane of the image pickup apparatus is optically controlled by a zoom lens and a focus lens. A controller drives the zoom lens to its telephoto position and drives the focus lens to its closest position so that bright image light is prevented from being focused on the photosensing plane.

1. Field of the Invention
The present invention relates to an image pickup apparatus which uses an image pickup device such as a video camera, and more particularly to an exposure control therefor.
2. Related Background Art
Iris vanes for directly controlling the amount of light incident onto an image pickup device has usually been used as means for attaining a function called the exposure correction in the video camera. However, in the iris vane approach, the iris vanes and peripheral mechanical components are required and it has been a barrier in attaining small size, small weight and low cost. As one of means for solving the problem, a method for controlling the exposure by an electronic shutter function which controls a charge accumulation time of the image pickup device without using the iris vanes has been proposed.
However, in the exposure control which uses the iris vanes, the iris vanes are in a fully closed position when a power of the image pickup apparatus is turned off so that the incidence of a light to the image pickup device is prevented. On the other hand, when the iris vanes are removed and the exposure control is effected only by the electronic shutter function, the light of the object is always directed to the image pickup device even after the power of the image pickup apparatus is turned off. As a result, if a light from an extremely high brightness object is directed to the image pickup device when the power of the image pickup apparatus is turned on, a large amount of charges are generated in the image pickup device and the charges overflow from pixels and flow into adjacent pixels or vertical transfer areas (blooming phenomenon and smear phenomenon). This results in a very dirty screen.

Image pickup apparatus with image light focus prevention


A closure and a container having the same closure are provided. The closure includes a sealing portion assembled to an aperture of a container to seal the container; a plurality of locking protrusions, each lock protrusion connected to a hinge extending from a lower rim of the sealing portion to protrude inwards and fixed to a locking flange formed on the container; a cover portion having a ring shape and assembled to an outside of the sealing portion to be vertically movable with respect to the sealing portion; and a plurality of fixing protrusions protruding from an inner circumferential surface of the cover portion to support the locking protrusions.

A container for storing beverages, powder or other contents is generally provided with a closure which is required to have a variety of functions depending on the usage of the container or the contents to be stored in the container.
For example, a carbonated drink container should keep its internal pressure over the atmospheric pressure, so it is important to maintain the airtightness of its closure during the distribution procedure.
In case of a container with a relatively larger capacity, it is preferred that the container has a closure which can be conveniently resealed after the closure is opened, so that the contents remaining in the container can be stored without deterioration. For example, a cork closure ensures excellent airtightness but has some inconvenience in that the cork closure may not be easily opened.
As another example, a screw top frequently used for general beverage containers is inconvenient because the screw top should be rotated. In particular, many children are inexperienced in rotating the screw top to open or close the container, so they may feel inconvenience in using the screw top.
The screw top should be strongly fastened in order to prevent contents from leaking out. In this case, however, the fastened screw top may not be easily opened again. To the contrary, if the screw top is not so tightly closed that the screw top can be easily opened again, the contents of the container may be leaked out.
In order to solve the above problems, the inventor of the present invention has proposed a closure structure ensuring convenient use, as disclosed in Korean Patent No. 10-575259 (issued on Apr. 24, 2006), Korean Patent No. 10-757795 (issued on Sep. 5, 2007) and Korean Utility Model Registration No. 20-385497 (issued on May 21, 2005). The closures as disclosed in the above documents can be opened or closed by just one touch, so that they can be more conveniently used in comparison to a screw top.

Closure and container having the same closure


Improved systems and methods for navigating and interacting in virtual communication environments are described. At least some of these systems and methods provide a framework that includes one or more virtual areas and supports realtime communications between the communicants. At least some of these systems and methods provide an interface that includes navigation controls that enable a user to navigate virtual areas and interaction controls that enable the user to interact with other communicants in the one or more virtual areas.

When face-to-face communications are not practical, people often rely on one or more technological solutions to meet their communications needs. These solutions typically are designed to simulate one or more aspects of face-to-face communications. Traditional telephony systems enable voice communications between callers. Instant messaging (also referred to as "chat") communications systems enable users to communicate text messages in real time through instant-message computer clients that are interconnected by an instant message server. Some instant messaging systems additionally allow users to be represented in a virtual environment by user-controllable graphic objects (referred to as "avatars"). Interactive virtual reality communication systems enable users in remote locations to communicate over multiple real-time channels and to interact with each other by manipulating their respective avatars in three-dimensional virtual spaces. What are needed are improved systems and methods for interfacing with virtual communication environments.

Shared virtual area communication environment based apparatus and methods


An asset tracking system that utilizes a wireless network system and has primary (main) and secondary (sub) tracking devices or ‘tags’ that are assigned to assets. The main tracking device acts as a coordinator and the sub tracking devices surrounding the coordinator act as end-devices. Each main device acts as a gateway network to long range communication while each sub device can only communicate in proximity profile (short range or nearby communication). Each sub device can communicate only with a main device. The main device passes data from the sub device to a remote host transparently. Each sub device sends its data when it triggered by a ‘ping’ from the main device.

In today's industry, success or failure depends in part upon knowing the up-to-date status of various assets. For example, in the freight delivery business, up-to-date knowledge of the location and, in some instances, the environment of various assets, such as pallet goods, is critical to efficient and reliable operations. Failure to maintain up-to-date status information can result in temporarily lost assets, sub-optimal use of the assets, and in the case of freight delivery, missed or late deliveries.
Recently, technologies have been developed that greatly assist in tracking locations of assets. For example, global positioning systems (GPS) use wireless signals transmitted by earth-orbiting satellites to calculate the position of a receiving device. Although relatively expensive, GPS receivers are capable of providing relatively accurate location information for virtually any point in the world.
More recently, radio frequency identification (RF or RFID) systems have been developed in which tracking or transmitting devices, often referred to as "tags," wirelessly communicate with readers. RF tracking systems are typically used in parcel tracking and sorting, container tracking, luggage tracking, retail tracking, warehouse tracking and inventory operations. The tracking devices may be either passive or active. Passive devices absorb signals transmitted by the reader and retransmit their own signals, such as identification information. While a passive device does not require a local power source, its resulting transmit range is relatively short, typically less than 1-2 meters. In contrast, an active device, which sends a signal to indicate its location, includes a local energy source (such as a battery) that improves transmission range. Depending on the wireless signal system used by the device, the range may be on the order of several meters or several hundred meters, or even miles. Regardless of the types of device used, knowledge of the location of the device allows users to identify the location of an asset that has the tracking device attached thereto.
Although a tracking system is highly useful, there is a large initial start-up cost associated with these tracking systems; the larger the system, the more tracking devices are needed. In order to decrease the overall cost of the system, utilizing primary tracking devices (main tags) and secondary tracking devices (sub tags) to provide the same level of asset tracking and protection but decrease overall system cost has been proposed (e.g., U.S. patent application publication 2015/0296332 entitled "Asset Tracking System Having Primary and Secondary Tracking Devices"). In this publication, some assets being tracked are furnished with primary tracking devices and others with secondary tracking devices, which cost less and have less features than the primary tracking device. With a high aspect ratio deployment between the primary and secondary devices to lower the system cost, a 100% deployment rate can be achieved.
In some systems such as of the publication discussed above, the primary tracking device (main tag) acts as a coordinator and the secondary devices (sub tags) surrounding the coordinator act as end-devices. Each secondary device can communicate only with the primary device in proximity. Even with this, the number of sub tags surrounding a main tag at a point of time can be variable and unknown. If the number of sub tags is too high, it may cause communication collisions. An absence of a main tag can lead to a power drain of the sub tag, since the sub tag will continue to attempt to establish a communication with a main tag, even if one cannot be found.
There is a need for heterogeneous communication between the main tag and sub tags to overcome the problems described above, and other problems, as will become apparent to one skilled in the art.

Wireless asset tracking systems with heterogeneous communication


There is provided a replaceable drywall saw blade capable of reciprocating in-line when mounted to a hand held reciprocating power saw. The blade includes a generally planar body member having a generally linear top edge and a generally parallel opposed bottom edge. The blade further includes a generally linear upper piercing edge angularly offset downwardly from the top edge. The blade additionally includes a generally linear lower piercing edge angularly offset upwardly from the bottom edge. The upper piercing edge and lower piercing edge intersect to form a forward point on said blade. A mounting aperture is also formed on the blade for releasably securing the blade to the hand held reciprocating power saw.

1. Field of the Invention
The present invention relates generally to saw blades and more particularly, to a saw blade for use with a reciprocating saw for cutting drywall.
2. Description of the Related Art
Drywall is widely used in the construction industry for both residential and commercial construction. Sheets of drywall may be pre-fabricated at an off-site location and delivered to the construction site. The drywall sheets may be quickly and easily attached to the structural frame to form a wall, ceiling, or other surface.
After the drywall is attached to the structural frame, it may be necessary to cut the drywall. For instance, an electrician may cut through the drywall to install recessed lighting in a ceiling. In addition, a plumber may cut through the drywall to access plumbing located behind the drywall. Various demolition projects may also require cutting or removal of certain sections of drywall.
Conventional drywall cutting tools may be used to cut through the drywall. A typical drywall cutter includes a blade that is 4″-9″ in length. A common problem associated with usage of such drywall cutting tools is that when the blade is inserted into the drywall, the blade may cut or damage utilities located behind the drywall. For instance, the blade may cut or damage electrical lines, plumbing, or other utilities disposed behind the drywall. Contact between the blade and the utilities may also place the individual cutting the drywall at risk of injury (e.g. electrical lines, gas lines). In addition, such contact may also create considerable damage, which may be very costly to fix. In the case of a hired contractor, the cost of repair may be greater than the profit expected for the original project.
Another problem associated with conventional drywall cutters relates to the dust generated when cutting the drywall. In particular, conventional drywall cutters tend to generate significant amounts of dust or debris when cutting the drywall. A standard sheet of drywall includes an inner chalky layer disposed between a pair of opposing outer paper-like layers. When the blade travels through the inner chalky layer, it has a propensity to pull chunks of the inner chalky layer out of the drywall sheet, which causes dust to settle in the areas surrounding the drywall. As such, the dusted areas typically require cleaning once the drywall is cut. The cleanup adds unwanted time and expense to the construction project.
As is apparent from the foregoing, there exists a need in the art for a drywall cutting blade configured to mitigate contact with utilities disposed behind the drywall as well as to reduce the dust generated with cutting the drywall. The present invention addresses this particular need, as will be discussed in more detail below.

Reciprocating saw blade for cutting drywall