Abstract: Nontoxic substances that block the N-methyl-D-aspartate (NMDA) receptor, e.g., a morphinan such as dextromethorphan or dextrorphan, or that block a major intracellular consequence of NMDA-receptor activation, e.g., a ganglioside such as GM1 or GT1b, a phenothiazine such as trifluoperazine or a naphthalenesulfonamide such as N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide, inhibit the development of tolerance to and/or dependence on addictive drugs, e.g., narcotic analgesics such as morphine, codeine, etc.

Abstract: A method and apparatus for knee replacement surgery wherein a femoral provisional component is provided which corresponds to a permanent component to be implanted in a human and which includes means for establishing the correct fit and position of such a component, prior to its implantation, in relation to the soft tissues of the knee before final resection of the anterior femoral surface. The provisional component further includes cutting guide means for such anterior surface resection such that accurate cuts may be made with the provisional component in place. The method involves preparing the distal femoral surface using the femoral intramedullary canal as a constant reference point for posterior and distal cutting guides followed by locating the provisional component by means of a provisional intramedullary stem so that the relationship with the soft tissues of the knee may be accurately established.

Abstract: An intelligent help system which processes information specific to a user and a system state is described. The system incorporates a monitoring device to determine which events to store as data in an historical queue. These data, as well as non-historical data (e.g., system state), are stored in a knowledge base. An inference engine tests rules against the knowledge base data, thereby providing a help tag. A display engine links the help tag with an appropriate solution tag to provide help text for display.

Abstract: A satellite television system that provides live television programming to passengers by integrating direct broadcast satellite services into an in-flight aircraft entertainment system. The system has an antenna disposed on the aircraft that is pointed at a plurality of satellites that are part of a direct broadcast satellite system. The antenna is controlled by an antenna controller and antenna interface unit that send control signals and process status signals to steer the antenna. The antenna is steered to lock it onto RF signals transmitted by the satellites. The antenna interface unit downconverts the received encoded RF signals to provide encoded left hand circularly polarized RF signals and right hand circularly polarized RF signals that contain different sets of television channels. The downconverted encoded RF signals are processed by a receiver to provide encoded video and audio signals of different television channels. The receiver does not decode or D/A convert the downconverted signals.

Abstract: The present invention is a variety of wearing apparel which employs two-dimensional patterns of optical illusions in three-dimensional applications in or upon the material of said wearing apparel. The applications of said patterns in the design of the apparel are for the purposes of a) novelty, b) highlighting body areas for attention and/or c) creating bodily appearance modification based on the natural properties of the optical illusion pattern itself.

Abstract: The disclosure describes vapor permeable retroreflective material for use on protective garments. The material may be formed in a non-continuous pattern that provides a high-level of retroreflective brightness, yet also provides adequate permeability to prevent exposure to trapped thermal energy and heated moisture. The non-continuous retroreflective pattern may include retroreflective regions and non-retroreflective regions arranged such that thermal decay through the protective garment is not substantially decreased in the regions corresponding to the retroreflective material. Rather, vapor permeation and thermal decay through the garment may be substantially the same as if the retroreflective material was not present.

Abstract: A rappeller's glove, that is adapted to be used as a pair on both hands of a person who is rappelling. The rappeller's glove is made up of a portion of film form material that covers the user's palm; digit portions extending outwardly from the palm portion, and preferably extending only partially up the digits that they are intended to cover, that are made up at least partially of film form material; a plurality of effectively discrete padded areas disposed on said palm portion; and a protective film overlay disposed over said discrete transverse padding areas adhered by stitching or otherwise to the palm portion to thereby define the plurality of padded areas, and covering an area including the place where the fingers and the main body portion of the user's hand are joined. Means to hold the glove tight against the wearer's wrist are disposed at the base of the glove. A composite of a rappeller's glove overlying a shooter's glove is also disclosed.

Abstract: A headmount apparatus for mounting vision enhancement equipment thereon which is comprised of a mounting shell having at least one pad and having at least one mounting surface to which the vision enhancing equipment is mounted, where at least one pad is configured to contact the user's head. The headmount apparatus is also comprised of at least one elastic strap which is attached to the mounting shell for securing the mounting shell to the user's head. The headmount apparatus for mounting vision enhancement equipment thereon could alternatively be comprised of at least one mounting frame for attaching vision enhancement equipment, at least one hardware mounting surface for accepting the mounting frame, and a hood configured to fit over a user's head where the hood is made at least in part from an elastic material and which contains the hardware mounting surface.

Abstract: A hat with enclosure for an insect screen has a generally planar top section and at least a first fabric member. The top section has a top edge and the first fabric member has a first edge and a second free edge. The first edge is connected to a portion of the top edge. The second edge is adjacent another portion of the top edge to define a closable opening there between. The fabric member and the top section define an enclosure that covers substantially entirely the top section. The insect screen has a portion connectable to either the top section or the fabric member adjacent the closable opening and is selectively insertable into the enclosure and deployable therefrom to cover a user's head. Preferably, the top section is partially covered by a second fabric member that also forms the enclosure.

Abstract: The sock is particularly adapted for use in Yoga exercises, Pilate exercises, stretching and other mat-based exercises, and comprises a sock made of a natural, plastic or synthetic fiber. The sock has five toe holes in the front end with webbing extending between the toe holes from the top of the sock to the bottom or sole of the sock to provide these openings through which the toes of a user can extend. The sock also has a layer of a PVC vinyl material on the bottom or sole of the sock which has a sticky or friction characteristic to enable the sock to grip a floor or mat when used by an exerciser, with or without the use of a mat, and to allow the toes to be exposed for tack or gripping functions.

Abstract: The main feature of the handkerchief valet is that it continually maintains the handkerchief in the same shape and height in the upper exterior left side chest pocket of a suit coat or sports coat or jacket as originally positioned.

Abstract: Safety apparel and/or non-apparel items that filter from the air one or more airborne particles and/or undesired gasses to provide safety to a human and/or non-human from potentially unhealthy airborne particles. The apparel and/or non-apparel item at least partially includes a filter material. The filter material on the apparel and/or non-apparel item has a sufficient size to enable the human and/or non-human to cover the nose, eyes, and/or mouth of the human and/or non-human. The filter material filters at least one airborne particle and/or undesired gas by a mechanical mechanism, an electrical mechanism, and/or a chemical mechanism. The apparel and/or non-apparel item can include at least one visual and/or textural indicator on the apparel and/or non-apparel item to at least partially indicate the location of the filter material on the apparel and/or non-apparel item.

Abstract: One embodiment of the present invention is apparel that includes: (a) a heat exchanger adapted to be worn in close proximity to a portion of a body; (b) a garment adapted to cover the heat exchanger; and (c) a multiplicity of anchors that couple the heat exchanger and the garment at a multiplicity of anchor locations.

Abstract: A bathing aid is designed to reduce the workload on the caregiver in bathing the physically challenged, elderly or similar persons requiring nursing care. The bathing aid is provided with an upward-opening cover for covering the open top of the bathtub except for an opening for allowing the bather to stick their head through. The cover is supported by arms urged upward by gas springs. The upward-opening cover allows the caregiver to stand whichever side of the bathtub and opens or closes the cover without difficulty. Furthermore, the cover's upward-opening structure is advantageous for reducing the installation space because it does not require the additional side space that would be necessary if the cover is constructed to open sideward.

Abstract: The invention relates to a device (2) for controlling and/or regulating the supply of a medium using a supply unit for an impingement device. Said supply unit comprises at least one shut-off member and each shut-off member can be moved into a closed position and at least one open position by means of an actuating element. The device comprises a sensor unit (50) for determining in a contactless manner the presence of a material that is to be impinged by the medium. The inventive device (2) is characterized in that said sensor unit (50) is additionally configured for the contactless determination of the relative position of the material in relation to the impingement device (10) and for the output of signals, which act on the actuating elements in such a way that the later moves the shut-oft members into a position that corresponds with the presence and the location of the material to be impinged by the medium.

Abstract: A toilet ramp serving as a movable device for supporting and transporting a toilet bowl once it is lifted off from a floor comprises a body of a rectangular shape having a opening at each of the two opposite sides for inspecting and removing a wax seal underneath the toilet bowl, a circular opening at the top of the ramp for providing access to the wax seal from the openings of the sides, and an adjustable handle on the front side of the ramp.

Abstract: A water diversion apparatus for a standard toilet tank having a fitting connected to a discharge tube and a water supply, such that the discharge tube discharges into an aesthetic container. The aesthetic container may be an aquarium or a cascade and pool. When the toilet is flushed, water is partially diverted from the toilet to the aesthetic container.

Abstract: A conduit cleaning or clearing apparatus and method has a housing assembly connectable to a pipeline. The housing has an inlet and outlet leg joined by a bight portion. A cleaning member is rotatably disposed within the housing and may be rotated from a first unobstructing position to a second cleaning position. In the cleaning position, a plurality of spaced apart blades are able to contact and loosen any build-up in the bight portion. A wiping paddle on the cleaning member urges the loosen build-up out the outlet leg and through the drain line. The paddle cooperates with a locator seat on the housing to retain the cleaning member in an unobstructing position when not cleaning or clearing the bight.

Abstract: A fitted bed sheet has a pair of roll guards mounted thereon to prevent a toddler or other person from rolling out of bed. Each roll guard is removably disposed in a slip cover mounted on the sheet by a flexible strip of material, which allows each roll guard to move between a first position atop the sheet and a second position beside the sheet with the roll guard hanging from the flexible strip. Each roll guard is securable in the raised position by the linking of fastener strips having hook and loop fasteners mounted on the slip cover and fabric loops mounted on the sheet. Each roll guard is removably mounted to the sheet via a zipper between the sheet and the flexible strip of material mounted on the slip cover. A plurality of elastic straps is mounted axially on the bottom of the sheet to help secure the sheet on a mattress.

Abstract: In accordance with the present disclosure, a gap filler is provided for a bed that includes first and second barriers. The gap filler is configured to substantially fill a gap defined between the first and second barriers.

Abstract: A siderail support mechanism with multiple locks and an impact release feature is configured to positively lock in an upright deployed position, but is adapted to release upon imposition of a longitudinal impact load such as that caused by striking a stationary barrier.

Abstract: A thermally-adaptive comforter which gives the user a greater amount of control over the temperature of their sleeping environment. The invention accomplishes this objective by providing a comforter with hatches which allows the user to vary the thermal conductivity of the comforter in certain areas. The comforter includes a plurality of hatch covers, having different colors or designs, which are placed over hatch openings. The hatch covers are detachably fastened to the comforter so that the hatch covers may be rearranged to change the appearance of the comforter. This feature of aesthetic design variability allows the user to change the appearance of the comforter as desired.

Abstract: An infant support apparatus for supporting an infant lying prone on its torso, configured to aid in soothing the infant and to aid in relieving and reducing the infant's gas pains. The infant support apparatus supports the head of the infant, the torso of the infant, and the legs of the infant such that the infant's head is elevated above its torso and its legs. The infant support apparatus is optionally fire retardant and fire resistant and includes a removable washable cloth cover. Retaining straps are used for holding the infant on the support apparatus. The infant support apparatus is shaped to conform to an underlying surface.

Abstract: An alternating pad consisting of transverse inflatable cells (1 and 2) alternately inflated and deflated. An internal cell (5) is provided at the outermost edges of each transverse cell (1,2). The internal cell (5) is constantly inflated at a higher pressure than the traverse cells (1, 2). The internal cell (5) is at a lower height than the cells (1,2) and preferably of a chamfered shape to provide optimum pressure relief across the whole surface of the pad. The internal cell (5) provides stable patient exit, entry or transfer from a bed or seat.

Abstract: A double chambered transfer mattress is provided capable of partial deflation that that includes a top inflatable mattress and a bottom inflatable mattress that are separated by a common wall from one another. A selectable inlet/outlet valve is arranged for airflow communication between an interior chamber of the bottom inflatable mattress and a source of pressurized air. A one-way valve is positioned through the common wall so as to provide selective air flow communication between the top inflatable mattress and the bottom inflatable mattress so that when the inlet/outlet valve is opened, so as to deflate the bottom inflatable mattress, the one-way valve is actuated so as to prevent deflation of the top inflatable mattress.

Abstract: The invention provides a novel adjustable mattress and pillow system and related methods in which a sensing mat positioned on the top face of a mattress affects microprocessor-controlled optimization of the contour of the mattress and a pillow based on a user's position. In one embodiment, the novel adjustable mattress and pillow system of the invention provides real time contour optimization through use of a variety of sensing techniques that make the system particularly useful in environments such as hospital critical care facilities where proper positioning of a user on a mattress and a pillow may prove important to user's health.

Abstract: An adhesive tape brush for cleaning fabric includes a handle and a brush head. Multiple cleaning sheets are removably supported on a lower and upper surfaces of the brush head in a separable roll, non-movably fixed on the brush head. When the outermost sheet becomes soiled, the sheet may be peeled away to expose an underlying non-soiled sheet. The brush head is fixed relative to the handle so that the web of sheets is not movable to create a high amount of friction when the outermost sheet is engaged and moved along with a surface. An elongated tape roll refill has perforations in at least one location to allow the roll to be separated into smaller width portions for individual use. Another tape roll refill has a generally nominal circular cross-section, but is deformable to an oblate shape to be mountable on either circular or oblate shaped brush heads.

Abstract: A long handled scraper clamped onto a broom and/or dustmop handle.

Abstract: A brush for suede shoes, or any other object made of napped material, hasving a one-piece molded plastic handle having a hollow interior with a planar outwardly-facing bristle-mounting surface, a collar extending annularly about the bristle-mounting surface and a gripping portion extending centrally from the collar transversely oppositely of the bristle-mounting surface. Bristles are embedded in and extend outwardly from the bristle-mounting surface. A hollow removable erasing rubber sleeve is configured for essentially complemental fitting over the gripping portion. Paired apertures and protrusions fit together to retain the hollow removable erasing rubber sleeve in complemental contact overlying the gripping portion of the handle of the brush.

Abstract: An industrial oil/dust collector is provided with a base, a motor and an air blower are installed on the exterior of the base, an air-inlet pipe and an air-outlet pipe are provided at the front of the motor to carry out quick suction and drainage functions, and inside the base there are an oil-collecting tank and a spare oil-collecting tank provided with multiple filtering devices to filter impurities of the oil, so as to prolong the service life of the motor and the air blower.

Abstract: The present invention relates to an apparatus of driving an agitator of an upright vacuum cleaner. It includes a fixing panel and a rotation guide which are positioned at an outer side of the driving shaft roller and guided to move coaxially with the driving shaft roller so as to conveniently switch a power transmitted to an agitator by a user's foot; a support sphere and a roller support part which are formed in a direction of an axis parallel with the driving shaft roller on an outer circumference of the rotation guide; an idle roller which is inserted into the roller support part; a manipulating means connected with the support sphere, for controlling the rotation guide so that the elastic member is selectively wound around the driving shaft roller or the idle roller; and a stop means for maintaining a position of the rotational driving part stably.

Abstract: A hinge has a pin, a rotating positioning element and a stationary positioning element. The rotating positioning element is mounted around the pin and has a first, second, third and fourth detent and a rear surface with an inner circular area and an outer circular area. The first and second detents are formed in the inner circular area. The third and fourth detents are formed in the outer circular area. Each detent has a centerline. The centerlines of the first and third detents coincide. The centerlines of the second and fourth detents coincide. The stationary positioning element is mounted around the pin and has a first protrusion and a second protrusion. The first protrusion is formed on the stationary positioning element and selectively engages the first and second detents. The second protrusion is formed on the stationary positioning element and selectively engages the third and fourth detents.

Abstract: A hinge device of a portable terminal connects a keyboard member to a comparatively massive display member and has cam and friction mechanisms. The cam mechanism has a fixing cam for axially receiving a shaft which extends into a cam case having a rotation arresting mechanism fixed on the shaft, a slider cam provided slidably in a manner to confront the fixing cam restrained in its rotation by the cam case, and an elastic mechanism for pressing the slider cam toward the fixing cam. The friction mechanism has a friction ring attached to the shaft and fitted into the friction case under pressure with a rotatable rotation arresting mechanism, so that both of automatic close lock function from a predetermined closed angle between the first and second members and a free stop function when opening and closing operation of the first and second members can be realized together without strain.

Abstract: An equipment with pivoting handles. The equipment includes a support and a pivoting handle that are assembled by at least one pivot pin, the pivoting handle being able to rest on at least one surface of the support. The handle includes at least one bearing surface and the equipment includes at least one pad of elastic material arranged to be compressed against the support by the bearing surface when the handle is resting on the surface of the support. The equipment may be applied for example to suspended equipment for aircraft consoles.

Abstract: A handle applied in bathroom and fixed on the wall. The handle is composed of a handhold pipe, a garnering rack, several supporting rods and covers, a middle positioning body and two side positioning bodies. The handle pipe is a hollow tube and holes sit at the middle and both ends respectively to match with middle positioning body, end positioning bodies and supporting rack tube holes separately. All holes will be bolted and be positioned; the other end will be bound to the positioning piece fixed on the wall and covered by cover which located on the supporting rack. Both ends of the garnering rack will be inserted into the hollow tubes of the end positioning bodies to be positioned and assembled. Hence, the whole assembling processes provide an easy, convenient, quick and time-saving effect and complete the purpose of fastness and safety to prevent loosen and fallen off.

Abstract: A former head for dry forming fibrous tissue in which a fiber material is mixed with air introduced to at least one rotating drum in a former head by injection. The drum is provided internally with means for fluidizing the injected fibers simultaneously, enabling higher production capacity and an increased distribution quality of the fibers. This former head has high capacity and an increased width, preferably over four meters, which avoids natural oscillations in the needle rollers as they are substituted by slotted air nozzles. The nozzles extend along a whole length of the drum and have adjustable nozzle lips to regulate the amount of air and direction of the air-flow blown through the perforations of the drum. Surprisingly, the capacity of the former head is markedly higher than conventional devices and distribution quality also is markedly better than by high-speed operation of traditional machines.

Abstract: A tie for bundling a plurality of elongated objects is formed in a generally arcuate configuration from a material having shape retaining memory properties. Complemental teeth on two opposed surface lock the two surfaces together to form a closed loop.

Abstract: A tie strap assembly for encircling and securing bundles of articles or discrete items including a looped tie strap or elastic band and a coupler for engaging opposite ends of the strap. The coupler includes an elongated shank having hook shaped arms on one end and an open ring on the opposite end. Protrusions are provided on the ring for capturing one end of the strap and keeper arms protrude from the shank to aid in holding the opposite end of the strap on the hook shaped arms. The ring has an open center for hanging the assembly for storage.

Abstract: A strap tenser includes a frame, a pin, a handle and an automatic reeling device. The pin is installed on the frame. The handle is pivotally installed on the pin. The handle includes a crossbar around which a first strap is wound after it is wound around the pin. The automatic reeling device includes a pin, a wheel, a cap, a crossbar and a spiral spring. The pin is installed on the frame and connected with an end of the second strap. The wheel is rotationally installed on the pin of automatic reeling device. The cap is rotationally installed on the pin thereof. The crossbar extends between the wheel and the cap eccentrically for reeling in the second strap. The spiral spring includes a first end secured to the frame and a second end secured to the cap.

Abstract: A safety buckle comprising a substantially flat elongated body comprising a first distal end opposite to a second distal end, the elongated body having a front surface and a back surface; and first, second and third slots, respectively formed in the elongated body, wherein the first, second and third slots are approximately parallel in direction to each other, so that a first blade is formed between the first and second slots, and a second blade is formed between the second and third slots, wherein the second and third slots are configured to receive a first end of a strap by way the first end being tied around the second blade, and wherein the first and second slots are configured to receive a second opposite end of the strap by way of the second end being wrapped around the first blade.

Abstract: A vertically positioned, lanyard, releasing breakaway buckle including a keeper and a secure. The keeper has a rear wall, side walls and a floor. A cover, to which a lanyard is secured, is hinged to the keeper and spaced apart from the floor. The cover defines an elongated slot. Apertures are formed inward from the side walls such that a strap may be fed through the apertures to vertically orient the buckle on a strap. The cover has a caming surface formed on the under surface of the cover, and which caming surface terminates in locking surface. An opening formed in the cover. A secure part includes a base, and a tongue section extending from the base. The tongue section has parallel guide arms extending from the rear wall forwardly, and terminating in leading ends, a member secured to the guide arms, and a caming surface formed in the tongue section.

Abstract: An apparatus for needling a non-woven material is described, comprising at least one needleboard (1) which is drivable in a reciprocating manner in the needle-penetration direction (6) as well as in the direction of the passage (11) of the non-woven material, comprising an eccentric drive for the needleboard (1) which comprises two parallel eccentric shafts (2, 3) which are drivable in opposite directions and assume a different angular position (?), and couplers (5) which connect the connecting rods (4) of the two eccentric shafts (2, 3) in an articulated manner and comprise a guide arm (8) which is rigidly connected with the same, and a lifting guide means (9) for the guide arms (8) which forms a swiveling axis (10) for the guide arms (8) which is parallel to the eccentric shafts (2, 3). In order to provide advantageous constructional conditions it is proposed that either the guide arms or the couplers carry the needleboard.

Abstract: A method and apparatus for making an absorbent composite from continuous tow is disclosed. The method and apparatus includes the steps of or means for spreading a crimped tow; de-registering the crimped tow; shaping the de-registered tow to a substantially rectangular cross-section; and distributing a particulate onto the shaped tow. The line speed of the particulate laden, shaped tow is greater than 190 m/min.

Abstract: A method and kit for repairing vehicle door skins by reorienting vehicle hem flanges from a closed orientation to an open orientation to allow removal of a damaged door skin from a door frame and replacing with a new door skin with an open orientation hem flange that is reoriented to a closed orientation to integrate the door skin and door frame with an adhesive. The repair kit includes a first tool for lifting and opening the damaged door skin hem flange to allow removal of the damaged door skin and reuse of the door frame. The tool kit includes a second repair tool for reorientation and closing the new door skin replacement door skin hem flange on the reused door frame with an adhesive to provide a repaired vehicle door with the replacement skin and reused door frame integral as a vehicle door.

Abstract: The present invention provides a method and apparatus of recycling a printed circuit board for separating and retrieving a metallic material, which includes a printed metallic material, and an insulating material, both composing the printed circuit board. Both the metallic material and the insulating material, which are separated and retrieved, are possible for recycling. In the method for recycling the printed circuit board, hot filtration equipment 4a and resin-metal separation equipment 51 are used in hot filtration process P400. The waste printed circuit board 1 is heated and force-filtered so that only the insulating material 1a pass through the filter. Then, the insulating material 1a and the metallic material 1b are separated and retrieved. It is preferred that the insulating body base 23 of the printed circuit board 100 as the waste printed circuit board is made of thermoplastic resin or a mixture of thermoplastic resin and inorganic loading material.

Abstract: A method and apparatus for coupling together the ends of two steel pipe sections, each of which contains a permeable inner liner, in which not only are the pipe ends held in abutting engagement, but gas contained within the liner of one pipe section is effectively channeled into the liner of the other pipe section.

Abstract: An expandable tubular coupling (10) includes first and second thread portions (12,14) each comprising a plurality of inter-engaging teeth (20,22), wherein at least one tooth on the first thread portion (12) engages a corresponding tooth on the second thread portion (14) and the remainder of said inter-engaging teeth (20,22) define respective gaps (32) therebetween.

Abstract: A thread cutting milling tool comprises a shank with a working portion formed with a recess for receiving a thread cutting insert. The thread cutting insert has one edge formed with a line of thread-form teeth of identical profile. The thread cutting teeth project laterally for cutting engagement with a work-piece while the tool spins about its axis. The tool also orbits within or about a work piece, and in one orbit of the tool in a helical cutting path relative to the work piece a number of complete turns of the screw-thread are formed which is equal to the number of teeth of the insert in engagement with the work-piece. A secondary cutter carried on the thread cutting milling tool provides for formation of a pilot portion or counter bore on the work piece at an end of the screw thread. The pilot portion or counter bore provides for alignment of a threaded member which is to engage the screw thread.

Abstract: A microphone assembly comprises a microphone, a connector secured to the underside of the microphone. A gasket has a sound collecting hole and is secured on the upper surface of the microphone.

Abstract: An ultra-miniature magnetic device generally comprises a conductive winding and a magnetic core. The conductive winding includes an upper conductor and a lower conductor. The magnetic core is of an elongate rectangular or oval shape having two elongate sections and two short sections. The lower conductor is preferably positioned below the elongate sections of the magnetic core while the upper conductor is preferably positioned above the elongate sections of the magnetic core. The lower and upper conductors are electrically connected by conducting via structures that are formed in sequential steps using semiconductor processing technology. The result is a coil winding around the elongate sections, with the short sections being preferably free of windings. The process provides an advantage of avoiding shorting between the via structures and the magnetic core caused by overetching when etching the via holes.