Fatigue evaluation of socket welded piping in nuclear power plant
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vecchio, R.S.
1996-12-01
Fatigue failures in piping systems occur, almost without exception, at the welded connections. In nuclear power plant systems, such failures occur predominantly at the socket welds of small diameter piping ad fillet attachment welds under high-cycle vibratory conditions. Nearly all socket weld fatigue failures are identified by leaks which, though not high in volume, generally are costly due to attendant radiological contamination. Such fatigue cracking was recently identified in the 3/4 in. diameter recirculation and relief piping socket welds from the reactor coolant system (RCS) charging pumps at a nuclear power plant. Consequently, a fatigue evaluation was performed to determinemore » the cause of cracking and provide an acceptable repair. Socket weld fatigue life was evaluated using S-N type fatigue life curves for welded structures developed by AASHTO and the assessment of an effective cyclic stress range adjacent to each socket weld. Based on the calculated effective tress ranges and assignment of the socket weld details to the appropriate AASHTO S-N curves, the socket weld fatigue lives were calculated and found to be in excellent agreement with the accumulated cyclic life to-date.« less
Socket welds in nuclear facilities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson, P.A.; Torres, L.L.
1995-12-31
Socket welds are easier and faster to make than are butt welds. However, they are often not used in nuclear facilities because the crevices between the pipes and the socket sleeves may be subject to crevice corrosion. If socket welds can be qualified for wider use in facilities that process nuclear materials, the radiation exposures to welders can be significantly reduced. The current tests at the Idaho Chemical Processing Plant (ICPP) are designed to determine if socket welds can be qualified for use in the waste processing system at a nuclear fuel processing plant.
Residual-stress measurement in socket welded joints by neutron diffraction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hayashi, M.; Ishiwata, M.; Minakawa, N.
1994-12-31
Neutron diffraction measurements of lattice strains provide spatial maps of residual stress near welds in ferritic steel socket joints. The highest tensile stresses in the welds are found in axial, radial and hoop direction at the weld root. However, the highest tensile stress in the axial direction is about 110MPa. Balancing compressive stresses are found near the surface of the socket weld fusion zone. Heat treatment at 600 C for 2 hours is sufficient to relieve residual stress in socket welds.
Fatigue strength of socket welded pipe joint
DOE Office of Scientific and Technical Information (OSTI.GOV)
Higuchi, Makoto; Hayashi, Makoto; Yamauchi, Takayoshi
1995-12-01
Fully reversed four point bending fatigue tests were carried out on small diameter socket welded joints made of carbon steels. Experimental parameters were pipe diameter, thicknesses of pipe and socket wall, throat depth and shape of fillet welds, slip-on and diametral gaps in the socket welding, lack of penetration at the root of fillet welds, and peening of fillet welds. In most cases a fatigue crack started from the root of the fillet, but in the case of higher stress amplitude, it tended to start from the toe of fillet. The standard socket welded joint for a pipe with amore » 50 mm nominal diameter showed a relatively low fatigue strength of 46 MPa in stress amplitude at the 10{sup 7} cycles failure life. This value corresponds to about 1/5 of that for the smoothed base metal specimens in axial fatigue. The fatigue strength decreased with increasing pipe diameter, and increased with increasing thickness of the pipe and socket wall. The effects of throat depth and shape of fillet welds on fatigue strength were not significant. Contrary to expectation, the fatigue strength of a socket welded joint without slip-on gap is Higher than that of the joint with a normal gap. A lack of penetration at the root deleteriously reduced fatigue strength, showing 14 MPa in stress amplitude at the 10{sup 7} cycles failure life for the 50 mm diameter socket joint.« less
46 CFR 56.30-5 - Welded joints.
Code of Federal Regulations, 2010 CFR
2010-10-01
... systems and should be checked when designing for these systems. (c) Socket welds (Modifies 127.3.3A.). (1) Each socket weld must conform to ASME B16.11 (incorporated by reference; see 46 CFR 56.01-2), to... approximately one-sixteenth inch between the end of the pipe and the bottom of the socket must be provided...
46 CFR 56.30-5 - Welded joints.
Code of Federal Regulations, 2012 CFR
2012-10-01
... systems and should be checked when designing for these systems. (c) Socket welds (Modifies 127.3.3A.). (1) Each socket weld must conform to ASME B16.11 (incorporated by reference; see 46 CFR 56.01-2), to... approximately one-sixteenth inch between the end of the pipe and the bottom of the socket must be provided...
46 CFR 56.30-5 - Welded joints.
Code of Federal Regulations, 2011 CFR
2011-10-01
... systems and should be checked when designing for these systems. (c) Socket welds (Modifies 127.3.3A.). (1) Each socket weld must conform to ASME B16.11 (incorporated by reference; see 46 CFR 56.01-2), to... approximately one-sixteenth inch between the end of the pipe and the bottom of the socket must be provided...
46 CFR 56.30-5 - Welded joints.
Code of Federal Regulations, 2013 CFR
2013-10-01
... systems and should be checked when designing for these systems. (c) Socket welds (Modifies 127.3.3A.). (1) Each socket weld must conform to ASME B16.11 (incorporated by reference; see 46 CFR 56.01-2), to... approximately one-sixteenth inch between the end of the pipe and the bottom of the socket must be provided...
46 CFR 56.30-5 - Welded joints.
Code of Federal Regulations, 2014 CFR
2014-10-01
... systems and should be checked when designing for these systems. (c) Socket welds (Modifies 127.3.3A.). (1) Each socket weld must conform to ASME B16.11 (incorporated by reference; see 46 CFR 56.01-2), to... approximately one-sixteenth inch between the end of the pipe and the bottom of the socket must be provided...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Higuchi, Makoto; Nakagawa, Akira; Chujo, Noriyuki
1996-12-01
Rotating bending fatigue tests were conducted on socket welded joints of a nominal diameter 20 mm, and effects of root defect and other various factors, including post-weld heat treatment (PWHT), pipe wall thickness, and socket wall thickness, were investigated. The socket joints exhibited, in the rotating bending fatigue mode, fatigue strengths that were markedly lower than the same 20 mm diameter joints in four-point bending fatigue. Also, where the latter specimens failed always at the toe, root-failures occurred in rotating bending fatigue. When PWHT`d, however, the fatigue strength showed a remarkable improvement, while the failure site reverted to toe. Thickermore » pipe walls and socket walls gave rise to higher fatigue strength. A formula relating the size of root defects to the fatigue strength reduction has been proposed.« less
46 CFR 154.528 - Piping joints: Flange type.
Code of Federal Regulations, 2014 CFR
2014-10-01
... following types: (1) Welding neck. (2) Slip-on. (3) Socket weld. (b) If the piping is designed for a... nominal pipe size is 100 mm (4 in.) or less; (2) Socket weld, if the nominal pipe size is 50 mm (2 in.) or...
46 CFR 154.528 - Piping joints: Flange type.
Code of Federal Regulations, 2011 CFR
2011-10-01
... following types: (1) Welding neck. (2) Slip-on. (3) Socket weld. (b) If the piping is designed for a... nominal pipe size is 100 mm (4 in.) or less; (2) Socket weld, if the nominal pipe size is 50 mm (2 in.) or...
46 CFR 154.528 - Piping joints: Flange type.
Code of Federal Regulations, 2012 CFR
2012-10-01
... following types: (1) Welding neck. (2) Slip-on. (3) Socket weld. (b) If the piping is designed for a... nominal pipe size is 100 mm (4 in.) or less; (2) Socket weld, if the nominal pipe size is 50 mm (2 in.) or...
46 CFR 154.528 - Piping joints: Flange type.
Code of Federal Regulations, 2013 CFR
2013-10-01
... following types: (1) Welding neck. (2) Slip-on. (3) Socket weld. (b) If the piping is designed for a... nominal pipe size is 100 mm (4 in.) or less; (2) Socket weld, if the nominal pipe size is 50 mm (2 in.) or...
Laboratory Investigation of a Leaking Type 316 Socket Weld in a Boron Injection Tank Sampling Line
NASA Astrophysics Data System (ADS)
Xu, Hongqing; Fyfitch, Steve; Hosier, Ryan; Hyres, James
A leak was discovered in a Type 316 stainless steel socket weld in the sampling line for the boron injection tank. A section of the pipeline containing the leaking weld was removed for laboratory investigation that included visual and Stereovisual inspections, liquid penetrant (PT) testing, metallography, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and ferrite content determinations. The leak path was a through-wall transgranular crack in the socket weld. Cracking initiated along the weld-metal-to-base-metal interface at the tip of the crevice between the socket and pipe. The crevice was exposed to oxygenated boron solution at <180°F. Shallow intergranular attack (IGA) was found in the exposed base metal inside the crevice. Based on the investigation results, it was concluded that transgranular stress corrosion cracking (TGSCC) is the primary cracking mechanism.
Langley Research Center Standard for the Evaluation of Socket Welds
NASA Technical Reports Server (NTRS)
Berry, R. F., Jr.
1985-01-01
A specification utilized for the nondestructive evaluation of socket type pipe joints at Langley Research Center (LaRC) is discussed. The scope of hardware shall include, but is not limited to, all common pipe fittings: tees, elbows, couplings, caps, and so forth, socket type flanges, unions, and valves. In addition, the exterior weld of slip on flanges shall be inspected using this specification. At the discretion of the design engineer, standard practice engineer, Fracture Mechanics Engineering Section, Pressure Systems Committee, or other authority, four nondestructive evaluation techniques may be utilized exclusively, or in combination, to inspect socket type welds. These techniques are visual, radiographic, magnetic particle, and dye penetrant. Under special circumstances, other techniques (such as eddy current or ultrasonics) may be required and their application shall be guided by the appropriate sections of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (B&PVC).
Vibrational fatigue failures in short cantilevered piping with socket-welding fittings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, J.K.
1996-12-01
Approximately 80% of the vibrational fatigue failures in nuclear power plants have been caused by high cycle vibrational fatigue. Many of these failures have occurred in short, small bore (2 in. nominal diameter and smaller), unbraced, cantilevered piping with socket-welding fittings. The fatigue failures initiated in the socket welds. These failures have been unexpected, and have caused costly, unscheduled outages in some cases. In order to reduce the number of vibrational fatigue failures in these short cantilevered pipes, an acceleration based vibrational fatigue screening criteria was developed under Electric Power Research Institute (EPRI) sponsorship. In this paper, the acceleration basedmore » criteria will be compared to the results obtained from detailed dynamic modeling of a short, cantilevered pipe.« less
46 CFR 56.15-1 - Pipe joining fittings.
Code of Federal Regulations, 2013 CFR
2013-10-01
... subpart 50.25 of this subchapter are acceptable for use in piping systems. (b) Threaded, flanged, socket-welding, buttwelding, and socket-brazing pipe joining fittings, made in accordance with the applicable...
46 CFR 56.15-1 - Pipe joining fittings.
Code of Federal Regulations, 2011 CFR
2011-10-01
... subpart 50.25 of this subchapter are acceptable for use in piping systems. (b) Threaded, flanged, socket-welding, buttwelding, and socket-brazing pipe joining fittings, made in accordance with the applicable...
46 CFR 56.15-1 - Pipe joining fittings.
Code of Federal Regulations, 2014 CFR
2014-10-01
... subpart 50.25 of this subchapter are acceptable for use in piping systems. (b) Threaded, flanged, socket-welding, buttwelding, and socket-brazing pipe joining fittings, made in accordance with the applicable...
46 CFR 56.15-1 - Pipe joining fittings.
Code of Federal Regulations, 2012 CFR
2012-10-01
... subpart 50.25 of this subchapter are acceptable for use in piping systems. (b) Threaded, flanged, socket-welding, buttwelding, and socket-brazing pipe joining fittings, made in accordance with the applicable...
NASA Technical Reports Server (NTRS)
Ding, Robert J.
2010-01-01
Some of the applications of advanced welding techniques are shown in this poster presentation. Included are brief explanations of the use on the Ares I and Ares V launch vehicle and on the Space Shuttle Launch vehicle. Also included are microstructural views from four advanced welding techniques: Variable Polarity Plasma Arc (VPPA) weld (fusion), self-reacting friction stir welding (SR-FSW), conventional FSW, and Tube Socket Weld (TSW) on aluminum.
Circuit reliability boosted by soldering pins of disconnect plugs to sockets
NASA Technical Reports Server (NTRS)
Pierce, W. B.
1964-01-01
Where disconnect pins must be used for wiring and testing a circuit, improved system reliability is obtained by making a permanent joint between pins and sockets of the disconnect plug. After the circuit has been tested, contact points may be fused through soldering, brazing, or welding.
46 CFR 154.528 - Piping joints: Flange type.
Code of Federal Regulations, 2010 CFR
2010-10-01
... and Process Piping Systems § 154.528 Piping joints: Flange type. (a) A flange must be one of the following types: (1) Welding neck. (2) Slip-on. (3) Socket weld. (b) If the piping is designed for a... less; or (3) Welding neck. (c) If the piping is designed for a temperature lower than −55 °C (−67 °F...
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 2 2010-10-01 2010-10-01 false Ends. 56.20-7 Section 56.20-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND APPURTENANCES Valves § 56.20-7 Ends. (a) Valves may be used with flanged, threaded, butt welding, socket welding or other ends...
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 2 2012-10-01 2012-10-01 false Ends. 56.20-7 Section 56.20-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND APPURTENANCES Valves § 56.20-7 Ends. (a) Valves may be used with flanged, threaded, butt welding, socket welding or other ends...
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 2 2014-10-01 2014-10-01 false Ends. 56.20-7 Section 56.20-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND APPURTENANCES Valves § 56.20-7 Ends. (a) Valves may be used with flanged, threaded, butt welding, socket welding or other ends...
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 2 2011-10-01 2011-10-01 false Ends. 56.20-7 Section 56.20-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND APPURTENANCES Valves § 56.20-7 Ends. (a) Valves may be used with flanged, threaded, butt welding, socket welding or other ends...
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 2 2013-10-01 2013-10-01 false Ends. 56.20-7 Section 56.20-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND APPURTENANCES Valves § 56.20-7 Ends. (a) Valves may be used with flanged, threaded, butt welding, socket welding or other ends...
24 CFR 3280.605 - Joints and connections.
Code of Federal Regulations, 2010 CFR
2010-04-01
... watertight for the pressures required under testing procedures. (1) Assembling of pipe. All joints and... or welding sockets of each fitting. Pipe threads and slip joints shall not be wrapped with string...
Fatigue testing of galvanized and ungalvanized socket connections.
DOT National Transportation Integrated Search
2014-09-01
The fatigue resistance of welded traffic signal support structure details is an ongoing research topic being : addressed at multiple universities primarily through state funding mechanisms. Fatigue problems with these : structures have plagued multip...
A study on fatigue strength reduction factor for small diameter socket welded pipe joints
DOE Office of Scientific and Technical Information (OSTI.GOV)
Higuchi, Makoto; Nakagawa, Akira; Hayashi, Makoto
1996-12-01
Factors that may exert influence on the fatigue strength of small diameter socket welded joints of nominal diameter in the 20--50 mm range have been investigated by the fully reversed four-point bending fatigue test with the material, diameter, pipe schedule, throat depth, bead shape, slip-on gap, and root defect as the testing parameters. The fatigue strength of socket joints depended acutely on the diameter. When the diameter is large, the fatigue strength tended to be low and the fracture is of the root-failure mode; when it is small, on the other hand, the fatigue strength is high and the fracturemore » is of the toe-failure mode. Stainless steel proved to be superior to carbon steel; it gave rise to 1.37 times the fatigue strength of the latter for socket joints of nominal diameter 50 mm; the fatigue strength reduction factor determined at 10{sup 7} cycles with respect to the fatigue strength of smooth base metal in the fully reversed fatigue was about 4 for stainless steel and about 5 for carbon steel. The fatigue strength was higher, the larger the Sche number (i.e., the thicker the pipe wall); it was improved markedly by placing one final refinement pass on the toe or by eliminating the slip-on gap. An empirical formula relating the size of the root defect to the fatigue strength reduction has been proposed.« less
Reusable vibration resistant integrated circuit mounting socket
Evans, Craig N.
1995-01-01
This invention discloses a novel form of socket for integrated circuits to be mounted on printed circuit boards. The socket uses a novel contact which is fabricated out of a bimetallic strip with a shape which makes the end of the strip move laterally as temperature changes. The end of the strip forms a barb which digs into an integrated circuit lead at normal temperatures and holds it firmly in the contact, preventing loosening and open circuits from vibration. By cooling the contact containing the bimetallic strip the barb end can be made to release so that the integrated circuit lead can be removed from the socket without damage either to the lead or to the socket components.
Möbius, R; Schleifenbaum, S; Grunert, R; Löffler, S; Werner, M; Prietzel, T; Hammer, N
2016-10-01
The removal of well-fixed acetabular components following THA (total hip arthroplasty) is a difficult operation and could be accompanied by the loss of acetabular bone stock. The optimal method for fixation is still under debate. The aim of this pilot study was to compare the tear-out resistance and failure behavior between osseo-integrated and non-integrated screw cups. Furthermore, we examined whether there are differences in the properties mentioned between screw sockets and cemented polyethylene cups. Tear-out resistance and related mechanical work required for the tear-out of osseo-integrated screw sockets are higher than in non-integrated screw sockets. Ten human coxal bones from six cadavers with osseo-integrated screw sockets (n=4), non-integrated (implanted post-mortem, n=3) screw sockets and cemented polyethylene cups (n=3) were used for tear-out testing. The parameters axial failure load and mechanical work for tear-out were introduced as measures for determining the stability of acetabular components following THA. The osseo-integrated screw sockets yielded slightly higher tear-out resistance (1.61±0.26kN) and related mechanical work compared to the non-integrated screw sockets (1.23±0.39kN, P=0.4). The cemented polyethylene cups yielded the lowest tear-out resistance with a failure load of 1.18±0.24kN. Compared to the screw cups implanted while alive, they also differ on a non-significant level (P=0.1). Osseous failure patterns differed especially for the screw sockets compared to the cemented polyethylene cups. Osseo-integration did not greatly influence the tear-out stability in cementless screw sockets following axial loading. Furthermore, the strength of the bone-implant-interface of cementless screw sockets appears to be similar to cemented polyethylene cups. However, given the high failure load, high mechanical load and because of the related bone failure patterns, removal should not be performed by means of tear-out but rather by osteotomes or other curved cutting devices to preserve the acetabular bone stock. Level III, case-control-study. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Reusable vibration resistant integrated circuit mounting socket
DOE Office of Scientific and Technical Information (OSTI.GOV)
Evans, C.N.
1993-12-31
This invention discloses a novel form of socket for integrated circuits to be mounted on printed circuit boards. The socket uses a novel contact which is fabricated out of a bimetallic strip with a shape which makes the end of the strip move laterally as temperature changes. The end of the strip forms a barb which digs into an integrated circuit lead at normal temperatures and hold it firmly in the contact, preventing loosening and open circuits from vibration. By cooling the contact containing the bimetallic strip the barb end can be made to release so that the integrated circuitmore » lead can be removed from the socket without damage either to the lead or to the socket components.« less
Reusable vibration resistant integrated circuit mounting socket
DOE Office of Scientific and Technical Information (OSTI.GOV)
Evans, C.N.
1995-08-29
This invention discloses a novel form of socket for integrated circuits to be mounted on printed circuit boards. The socket uses a novel contact which is fabricated out of a bimetallic strip with a shape which makes the end of the strip move laterally as temperature changes. The end of the strip forms a barb which digs into an integrated circuit lead at normal temperatures and holds it firmly in the contact, preventing loosening and open circuits from vibration. By cooling the contact containing the bimetallic strip the barb end can be made to release so that the integrated circuitmore » lead can be removed from the socket without damage either to the lead or to the socket components. 11 figs.« less
Investigation of a Modified 9Cr-1Mo (P91) Pipe Failure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Klueh, Ronald L; Shingledecker, John P
2006-04-01
A modified 9Cr-1Mo feedwater (condensate) line at an Eastman Chemical Company plant failed in January 2005. The line was in continuous service since start-up December 2001 until failure. The Plant Superintendent estimated there were three thermal cycles since start-up, although there may have been as many as 25 thermal cycles during commissioning. Normal operating temperature was 325 F (163 C) and pressure was 1762 psig. The line was steam traced with the tracing activated only when ambient outdoor temperature dropped to 40 F (5 C). A modified 9Cr-1Mo steel (P91) pipe failure in a feedwater line in a chemical plantmore » was investigated. The failure occurred in the vicinity of an elbow produced with socket welds of the pipe to the elbow. Based on metallography and hardness measurements, it was concluded that failure occurred because of an improper post-weld heat treatment of the socket weldment.« less
Improving socket design to prevent difficult removal of locking screws.
Lin, Chen-Huei; Chao, Ching-Kong; Tang, Yi-Hsuan; Lin, Jinn
2018-03-01
Reports of driver slippage leading to difficult locking screw removals have increased since the adoption of titanium for screw fabrication; the use of titanium is known to cause cross-threading and cold welding. Such problems occur most frequently in screws with hex sockets, and may cause serious surgical complications. This study aimed to improve screw socket design to prevent slippage and difficult screw removal. Three types of small sockets (hex, Torx, and cruciate) and six types of large sockets (hex, Torx, Octatorx, Torx+ I, Torx+ II, and Torx+ III) with screw head diameters of 5.5 mm were manufactured from titanium, and corresponding screwdrivers were manufactured from stainless steel. The screw heads and drivers were mounted on a material testing machine, and torsional tests were conducted to simulate screw usage in clinical settings at two insertion depths: 1 and 2 mm. Ten specimens were tested from each design, and the maximum torque and failure patterns were recorded and compared. For small sockets in 2 mm conditions, the hex with the largest driver core had the highest torque, followed by Torx and cruciate. In these tests, the drivers were twisted off in all specimens. However, under the 1 mm condition, the hex slipped and the torque decreased markedly. Overall, torque was higher for large sockets than for small sockets. The Octatorx, with a large core and simultaneous deformation of the driver and socket lobes, had the highest torque at almost twice that of the small hex. The hex had the lowest torque, a result of slippage in both the 1 and 2 mm conditions. Torx plus designs, with more designed degrees of freedom, were able to maintain a higher driving angle and larger core for higher torque. The hex design showed slipping tendencies with a marked decrease in torque, especially under conditions with inadequate driver engagement. Large sockets allowed for substantial increases in torque. The Torx, Octatorx, and Torx plus designs displayed better performance than the hexes. Improvements to the socket design could effectively prevent slippage and solve difficult screw removal problems. Copyright © 2018. Published by Elsevier Ltd.
Earth boring apparatus with multiple welds
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bolton, J.B.; Crews, S.T.
1981-06-16
A box tool joint member of generally tubular configuration is adapted for securement by welding to one end of a steel tube to form a drill pipe. The box tool joint member comprises a body having a cylindrical outer periphery, an internally threaded socket at one end of the body, and a weld neck of smaller outer diameter than the body adjacent to the other end of the body. A tapered transition piece connecting the neck with the adjacent end of the body provides an elevator shoulder. A correlative pin tool joint member is welded to the opposite end ofmore » the tube to complete the drill pipe. The box tool joint member has an annular band of hard facing over the outer periphery of the transition piece and extending down over the adjacent part of the weld neck and up around the adjacent part of the body. The hard facing is corrosion resistant and has a smooth finished surface. Underneath the hard facing and extending beyond both ends of the hard facing is an annular butter layer of non-hardenable steel. The tool joint member is hardened and tempered after the butter layer is welded into a body groove and before the hard facing is welded on .The butter layer is grooved before the hard facing is welded on.« less
Hefferman, Gerald M; Zhang, Fan; Nunnery, Michael J; Huang, He
2015-04-01
In recent years, there has been an increased interest in recording high-quality electromyographic signals from within the sockets of lower-limb amputees. However, successful recording presents major challenges to both researchers and clinicians. This article details and compares four prototypical integrated socket-sensor designs used to record electromyographic signals from within the sockets of transfemoral amputees. Four prototypical socket-sensor configurations were constructed and tested on a single transfemoral amputee asked to perform sitting/standing, stair ascent/descent, and level ground walking. The number of large-amplitude motion artifacts generated using each prototype was quantified, the amount of skin irritation documented, and the comfort level of each assembly subjectively assessed by the amputee subject. Of the four configurations tested, the combination of a suction socket with integrated wireless surface electrodes generated the lowest number of large-amplitude motion artifacts, the least visible skin irritation, and was judged to be most comfortable by the amputee subject. The collection of high-quality electromyographic signals from an amputee's residual limb while maximizing patient comfort holds substantial potential to enhance neuromuscular clinical assessment and as a method of intuitive control of powered lower-limb prostheses. © The International Society for Prosthetics and Orthotics 2014.
Hydroxyapatite ocular implant and non-integrated implants in eviscerated patients
Gradinaru, S; Popescu, V; Leasu, C; Pricopie, S; Yasin, S; Ciuluvica, R; Ungureanu, E
2015-01-01
Introduction: This study compares the outcomes and complications of hydroxyapatite ocular implant and non-integrated ocular implants following evisceration. Materials and Methods: This is a retrospective study of 90 patients who underwent evisceration for different ocular affections, in the Ophthalmology Department of the University Emergency Hospital Bucharest, between January 2009 and December 2013. The outcomes measured were conjunctival dehiscence, socket infection, implant exposure and extrusion rate. Results: Forty-three patients had the hydroxyapatite implant (coralline–Integrated Ocular Implants, USA or synthetic–FCI, France) and forty-seven received non-integrated ocular implants (24 acrylic and 23 silicone). Five cases of socket infection, thirteen cases of extrusion and two cases of conjunctival dehiscence were encountered. Conclusions: There was a higher rate of conjunctival dehiscence with hydroxyapatite ocular implant, but implant extrusion and socket infection were found in non-integrated ocular implants. PMID:25914747
76 FR 56279 - Airworthiness Directives; Airbus Model A318, A319, A320, and A321 Series Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-13
... to socket arcing at the Integrated Drive Generator (IDG) feeder cable pylon/nacelle interface connector. The fretting corrosion phenomenon was identified to be the root cause of the pin to socket arcing... products. The MCAI states: In service experience has shown a number of events of pin to socket arcing at...
A case series of anophthalmic socket cysts excised utilising fibrin sealant.
Wong, Yun; Clarke, Lucy; Lau, Gordon
2017-10-23
Anophthalmic socket cysts are challenging to remove and incomplete excision has been shown to increase the risk of recurrence. This case series describes a novel technique utilising the fibrin sealant Tisseel (Baxter AG, Vienna, Austria) to retain the socket cyst integrity during surgical removal to facilitate its complete excision. Five patients were included and followed up for a minimum of 1 year, and there were no signs of recurrence in any of the cases. The surgical technique is described and illustrated. This technique is a safe way of simplifying challenging socket cyst surgery.
Overall interior view of structures shop (11 shop) located on ...
Overall interior view of structures shop (11 shop) located on west side of building 57 - looking north; the south end of the structures shop was devoted to welding heavy plate foundations and ship components; the floor is fabricated of case steel and features a grillwork of 1 1/2 fabricated holes which are used as sockets for gripping position pins. - Naval Base Philadelphia-Philadelphia Naval Shipyard, Structure Shop, League Island, Philadelphia, Philadelphia County, PA
Alveolar socket healing: what can we learn?
Araújo, Mauricio G; Silva, Cléverson O; Misawa, Mônica; Sukekava, Flavia
2015-06-01
Tooth extraction induces a series of complex and integrated local changes within the investing hard and soft tissues. These local alterations arise in order to close the socket wound and to restore tissue homeostasis, and are referred to as '"socket healing". The aims of the present report were twofold: first, to describe the socket-healing process; and, second, to discuss what can be learned from the temporal sequence of healing events, in order to improve treatment outcomes. The socket-healing process may be divided into three sequential, and frequently overlapping, phases: inflammatory; proliferative; and modeling/remodeling. Several clinical and experimental studies have demonstrated that the socket-healing process promotes up to 50% reduction of the original ridge width, greater bone resorption at the buccal aspect than at the lingual/palatal counterpart and a larger amount of alveolar bone reduction in the molar region. In conclusion, tooth extraction, once a simple and straightforward surgical procedure, should be performed in the knowledge that ridge reduction will follow and that further clinical steps should be considered to compensate for this, when considering future options for tooth replacement. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Welded joints integrity analysis and optimization for fiber laser welding of dissimilar materials
NASA Astrophysics Data System (ADS)
Ai, Yuewei; Shao, Xinyu; Jiang, Ping; Li, Peigen; Liu, Yang; Liu, Wei
2016-11-01
Dissimilar materials welded joints provide many advantages in power, automotive, chemical, and spacecraft industries. The weld bead integrity which is determined by process parameters plays a significant role in the welding quality during the fiber laser welding (FLW) of dissimilar materials. In this paper, an optimization method by taking the integrity of the weld bead and weld area into consideration is proposed for FLW of dissimilar materials, the low carbon steel and stainless steel. The relationships between the weld bead integrity and process parameters are developed by the genetic algorithm optimized back propagation neural network (GA-BPNN). The particle swarm optimization (PSO) algorithm is taken for optimizing the predicted outputs from GA-BPNN for the objective. Through the optimization process, the desired weld bead with good integrity and minimum weld area are obtained and the corresponding microstructure and microhardness are excellent. The mechanical properties of the optimized joints are greatly improved compared with that of the un-optimized welded joints. Moreover, the effects of significant factors are analyzed based on the statistical approach and the laser power (LP) is identified as the most significant factor on the weld bead integrity and weld area. The results indicate that the proposed method is effective for improving the reliability and stability of welded joints in the practical production.
Survival of Implants in Immediate Extraction Sockets of Anterior Teeth: Early Clinical Results.
Sabir, Mohammad; Alam, Mohammad Nazish
2015-06-01
The aims and objectives of this study were placement of implants in freshly extracted sockets of anterior teeth and to evaluate the implant stability, peri-implant radiolucency and gingival inflammation around implant over a short period of 30 months. A total of 12 patients (8 male and 4 female), ranging in the age from 20 to 50 years, from March 2007 to June 2007, were evaluated for immediate implant placement into 22 fresh extraction sockets. Only maxillary and mandibular anterior teeth/roots (central incisors, lateral incisors and canines) were considered for replacement with implants. One piece implant with integrated abutment and integrated surface, non-submerged, threaded and tapered at apical 5 mm, sand-blasted and acid etched surfaced implants (HI-TEC TRX-OP Implants of Life Care Company) were used. The mobility was not present in any of the implants at all the follow up visits. There were 2 implants at 6 month, 1 implant at 12 month, 1 implant at 18 month visits, showing peri-implant radiolucency at some sites at bone to implant contact site. Severe gingival inflammation was not observed in any of the implant site. At every follow-up visit, every implant met the criteria of success and none was found to be failed over a 30 months duration i.e. 100% success rate was achieved by implants in immediate extraction socket. The success rate of implant survival in this study was found 100%. These implants have fulfilled all the criteria of implant success and based on the defined criteria, the success rate of implants placed in immediate extraction sockets of anterior teeth compared favorably with the conventional implants. The early results of the present study showed that high survival rates with the implants in immediate extraction sockets can be achieved.
Integrated Structural and Cable Connector
NASA Technical Reports Server (NTRS)
Totah, R. S.
1982-01-01
Ball-and-socket coupling includes fiber-optic cable. Three steps couple two parts of fiber-optic cable: ball is inserted into socket; cone is released in, and cable moves toward plug. Sleeve is pulled to end of its travel and cable and plug are mated. Device is a quick-connect/disconnect coupling that has application in hazardous environments, such as space, undersea and nuclear installations.
Kobayashi, Toshiki; Orendurff, Michael S.; Arabian, Adam K.; Rosenbaum-Chou, Teri G.; Boone, David A.
2014-01-01
The alignment of a lower limb prosthesis affects the way load is transferred to the residual limb through the socket, and this load is critically important for the comfort and function of the prosthesis. Both magnitude and duration of the moment are important factors that may affect the residual limb health. Moment impulse is a well-accepted measurement that incorporates both factors via moment–time integrals. The aim of this study was to investigate the effect of alignment changes on the socket reaction moment impulse in transtibial prostheses. Ten amputees with transtibial prostheses participated in this study. The socket reaction moment impulse was measured at a self-selected walking speed using a Smart Pyramid™ in 25 alignment conditions, including a nominal alignment (clinically aligned by a prosthetist), as well as angle malalignments of 2°, 4° and 6° (abduction, adduction, extension and flexion) and translation malalignments of 5 mm, 10 mm and 15 mm (lateral, medial, anterior and posterior). The socket reaction moment impulse of the nominal alignment was compared for each condition. The relationship between the alignment and the socket reaction moment impulse was clearly observed in the coronal angle, coronal translation and sagittal translation alignment changes. However, this relationship was not evident in the sagittal angle alignment changes. The results of this study suggested that the socket reaction moment impulse could potentially serve as a valuable parameter to assist the alignment tuning process for transtibial prostheses. Further study is needed to investigate the influence of the socket reaction moment impulse on the residual limb health. PMID:24612718
Protective Socket For Integrated Circuits
NASA Technical Reports Server (NTRS)
Wilkinson, Chris; Henegar, Greg
1988-01-01
Socket for intergrated circuits (IC's) protects from excessive voltages and currents or from application of voltages and currents in wrong sequence during insertion or removal. Contains built-in switch that opens as IC removed, disconnecting leads from signals and power. Also protects other components on circuit board from transients produced by insertion and removal of IC. Makes unnecessary to turn off power to entire circuit board so other circuits on board continue to function.
Kobayashi, Toshiki; Orendurff, Michael S; Arabian, Adam K; Rosenbaum-Chou, Teri G; Boone, David A
2014-04-11
The alignment of a lower limb prosthesis affects the way load is transferred to the residual limb through the socket, and this load is critically important for the comfort and function of the prosthesis. Both magnitude and duration of the moment are important factors that may affect the residual limb health. Moment impulse is a well-accepted measurement that incorporates both factors via moment-time integrals. The aim of this study was to investigate the effect of alignment changes on the socket reaction moment impulse in transtibial prostheses. Ten amputees with transtibial prostheses participated in this study. The socket reaction moment impulse was measured at a self-selected walking speed using a Smart Pyramid in 25 alignment conditions, including a nominal alignment (clinically aligned by a prosthetist), as well as angle malalignments of 2°, 4° and 6° (abduction, adduction, extension and flexion) and translation malalignments of 5 mm, 10 mm and 15 mm (lateral, medial, anterior and posterior). The socket reaction moment impulse of the nominal alignment was compared for each condition. The relationship between the alignment and the socket reaction moment impulse was clearly observed in the coronal angle, coronal translation and sagittal translation alignment changes. However, this relationship was not evident in the sagittal angle alignment changes. The results of this study suggested that the socket reaction moment impulse could potentially serve as a valuable parameter to assist the alignment tuning process for transtibial prostheses. Further study is needed to investigate the influence of the socket reaction moment impulse on the residual limb health. Copyright © 2014 Elsevier Ltd. All rights reserved.
Magnetic electrical connectors for biomedical percutaneous implants
NASA Technical Reports Server (NTRS)
Owens, L. J. (Inventor)
1977-01-01
A biomedical percutaneous connector is described which includes a socket having an enlarged disk shaped base portion for being implanted below the patient's skin and cylindrical portion which is integral with the base portion and extends outwardly of the skin. A conical recess in an upper end of the cylindrical portion has a magnet located in the base. Inclined conductive strips are carried on an upper end of the cylindrical portion to which electrical conductors are attached and extend into the patient's body. A complementary shaped plug which also has electrical contacts provided thereon is adapted to fit within the conical recess of the socket. The plug is held in the socket by magnetic force.
Survival of Implants in Immediate Extraction Sockets of Anterior Teeth: Early Clinical Results
Sabir, Mohammad
2015-01-01
Background The aims and objectives of this study were placement of implants in freshly extracted sockets of anterior teeth and to evaluate the implant stability, peri-implant radiolucency and gingival inflammation around implant over a short period of 30 months. Materials and Methods A total of 12 patients (8 male and 4 female), ranging in the age from 20 to 50 years, from March 2007 to June 2007, were evaluated for immediate implant placement into 22 fresh extraction sockets. Only maxillary and mandibular anterior teeth/roots (central incisors, lateral incisors and canines) were considered for replacement with implants. One piece implant with integrated abutment and integrated surface, non-submerged, threaded and tapered at apical 5 mm, sand-blasted and acid etched surfaced implants (HI-TEC TRX-OP Implants of Life Care Company) were used. Results The mobility was not present in any of the implants at all the follow up visits. There were 2 implants at 6 month, 1 implant at 12 month, 1 implant at 18 month visits, showing peri-implant radiolucency at some sites at bone to implant contact site. Severe gingival inflammation was not observed in any of the implant site. At every follow-up visit, every implant met the criteria of success and none was found to be failed over a 30 months duration i.e. 100% success rate was achieved by implants in immediate extraction socket. Conclusion The success rate of implant survival in this study was found 100%. These implants have fulfilled all the criteria of implant success and based on the defined criteria, the success rate of implants placed in immediate extraction sockets of anterior teeth compared favorably with the conventional implants. The early results of the present study showed that high survival rates with the implants in immediate extraction sockets can be achieved. PMID:26266220
NASA Technical Reports Server (NTRS)
Powell, John D.
2003-01-01
This document discusses the verification of the Secure Socket Layer (SSL) communication protocol as a demonstration of the Model Based Verification (MBV) portion of the verification instrument set being developed under the Reducing Software Security Risk (RSSR) Trough an Integrated Approach research initiative. Code Q of the National Aeronautics and Space Administration (NASA) funds this project. The NASA Goddard Independent Verification and Validation (IV&V) facility manages this research program at the NASA agency level and the Assurance Technology Program Office (ATPO) manages the research locally at the Jet Propulsion Laboratory (California institute of Technology) where the research is being carried out.
Adaptive weld control for high-integrity welding applications
NASA Technical Reports Server (NTRS)
Powell, Bradley W.
1993-01-01
An advanced adaptive control weld system for high-integrity welding applications is presented. The system consists of a state-of-the-art weld control subsystem, motion control subsystem, and sensor subsystem which closes the loop on the process. The adaptive control subsystem (ACS), which is required to totally close the loop on weld process control, consists of a multiprocessor system, data acquisition hardware, and three welding sensors which provide measurements from all areas around the torch in real time. The ACS acquires all 'measurables' and feeds offset trims back into the weld control and motion control subsystems to modify the 'controllables' in order to maintain a previously defined weld quality.
NASA Astrophysics Data System (ADS)
Darmawan, Tofiq Dwiki; Priadythama, Ilham; Herdiman, Lobes
2018-02-01
Welding and drilling are main processes of making chair frame from metal material. Commonly, chair frame construction includes many arcs which bring difficulties for its welding and drilling process. In UNS industrial engineering integrated practicum there are welding fixtures which use to fixing frame component position for welding purpose. In order to achieve exact holes position for assembling purpose, manual drilling processes were conducted after the frame was joined. Unfortunately, after it was welded the frame material become hard and increase drilling tools wear rate as well as reduce holes position accuracy. The previous welding fixture was not equipped with clamping system and cannot accommodate drilling process. To solve this problem, our idea is to reorder the drilling process so that it can be execute before welding. Thus, this research aims to propose conceptual design of modular fixture which can integrate welding and drilling process. We used Generic Product Development Process to address the design concept. We collected design requirements from 3 source, jig and fixture theoretical concepts, user requirements, and clamping part standards. From 2 alternatives fixture tables, we propose the first which equipped with mounting slots instead of holes. We test the concept by building a full sized prototype and test its works by conducting welding and drilling of a student chair frame. Result from the welding and drilling trials showed that the holes are on precise position after welding. Based on this result, we conclude that the concept can be a consideration for application in UNS Industrial Engineering Integrated Practicum.
Watkins, Arthur D.; Smartt, Herschel B.; Taylor, Paul L.
1994-01-01
An integrated optical sensor for arc welding having multifunction feedback control. The sensor, comprising generally a CCD camera and diode laser, is positioned behind the arc torch for measuring weld pool position and width, standoff distance, and post-weld centerline cooling rate. Computer process information from this sensor is passed to a controlling computer for use in feedback control loops to aid in the control of the welding process. Weld pool position and width are used in a feedback loop, by the weld controller, to track the weld pool relative to the weld joint. Sensor standoff distance is used in a feedback loop to control the contact tip to base metal distance during the welding process. Cooling rate information is used to determine the final metallurgical state of the weld bead and heat affected zone, thereby controlling post-weld mechanical properties.
Watkins, A.D.; Smartt, H.B.; Taylor, P.L.
1994-01-04
An integrated optical sensor for arc welding having multifunction feedback control is described. The sensor, comprising generally a CCD camera and diode laser, is positioned behind the arc torch for measuring weld pool position and width, standoff distance, and post-weld centerline cooling rate. Computer process information from this sensor is passed to a controlling computer for use in feedback control loops to aid in the control of the welding process. Weld pool position and width are used in a feedback loop, by the weld controller, to track the weld pool relative to the weld joint. Sensor standoff distance is used in a feedback loop to control the contact tip to base metal distance during the welding process. Cooling rate information is used to determine the final metallurgical state of the weld bead and heat affected zone, thereby controlling post-weld mechanical properties. 6 figures.
Abdelhamid, Alaa; Omran, Mostafa; Bakhshalian, Neema; Tarnow, Dennis; Zadeh, Homayoun H
2016-06-01
The aims of this study were (i) to evaluate the efficacy of ridge preservation and repair procedures involving the application of SocketKAP(™) and SocketKAGE(™) devices following tooth removal and (ii) to evaluate alveolar bone volumetric changes at 6 months post-extraction in intact sockets or those with facial wall dehiscence defects using 3-dimensional pre- and postoperative CBCT data. Thirty-six patients required 61 teeth extracted. Five cohorts were established: Group A: Intact Socket Negative Control Group B: Intact Socket + SocketKAP(™) Group C: Intact Socket Filled with Anorganic Bovine Bone Mineral (ABBM) + SocketKAP(™) Group D: Facial Dehiscence Socket Negative Control Group E: Facial Dehiscence Socket Filled with ABBM + SocketKAP(™) + SocketKAGE(™) . Preoperative CBCT scans were obtained followed by digital subtraction of the test teeth. At 6 months post-extraction, another CBCT scan was obtained. The pre- and postoperative scans were then superimposed, allowing highly accurate quantitative determination of the 3D volumetric alveolar bone volume changes from baseline through 6 months. Significant volumetric bone loss occurred in all sockets, localized mainly in the 0-3 mm zone apical to the ridge crest. For intact sockets, SocketKAP(™) + ABBM treatment led to a statistically significant greater percentage of remaining mineralized tissue volume when compared to negative control group. A significant difference favoring SocketKAP(™) + SocketKAGE(™) + ABBM treatment was observed for sockets with facial dehiscence defects compared to the negative control group. SocketKAP(™) , with ABBM, appears effective in limiting post-extraction volumetric bone loss in intact sockets, while SocketKAP(™) + SocketKAGE + ABBM appears effective in limiting post-extraction bone loss in sockets with dehiscence defects. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
High Coherence Qubit packaging
NASA Astrophysics Data System (ADS)
Pappas, David P.; Wu, Xian; Olivadese, Salvatore B.; Adiga, V. P.; Hertzberg, Jared B.; Bronn, Nicholas T.; Chow, Jerry M.; NIST Team; IBM Team
Development of sockets and associated interconnects for multi-qubit chips is presented. Considerations include thermalization, RF hygiene, non-magnetic environment, and self-alignment of the chips to allow for rapid testing, scalable integration, and high coherence operation. The sockets include wirebond free, vertical take-off launches with pogopins. This allows for high interconnectivity to non-trivial topology of qubits. Furthermore, vertical grounding is accomplished to reduce chip modes and suppress box modes. Low energy loss and high phase coherence is observed using this paradigm. We acknowledge support from IARPA, LPS, and the NIST Quantum Based Metrology Initiative.
Abd Razak, Nasrul A; Abu Osman, Noor A; Ali, Sadeeq A; Gholizadeh, Hossein
2016-01-15
While considering how important the interface between the amputees with the prostheses socket, we have carried out research to compare the gradient pressure occur at the interface socket that may lead to the discomforting effects to the user using common ICRC polypropylene socket and air splint socket. Not Applicable SETTING: Not Applicable POPULATION: The subject was a 23 year old who suffered a traumatic defect on the right arm caused by higher electrical volt. F-Socket sensors have been used to measure dynamic socket interface pressure for the transradial amputee wearer during static and dynamic movements. The printed circuit with a thickness of 0.18 mm is equipped between the socket and the surface of the residual limb. Two F-Socket sensor is required to cover the entire socket surface attached to the residual limb. The average of 10 trials made on prosthetic user using both type of sockets for static and dynamic movements was recorded. The pressure gradient shows that the circumference of the socket interface for the ICRC polypropylene socket gives the most pressure distributions to the amputees compared to the pressure gradient for the air splint socket. The pressure gradient for ICRC socket increased consistently when the user makes movements while for the air splint socket remain constantly. The specific interface pressure occur at the socket interface help in determine the comfort and pain of the socket design and improve the correlation between the user and the prosthesis.
Resnik, Linda; Patel, Tarpit; Cooney, Shane G; Crisco, Joseph J; Fantini, Christopher
2016-01-01
This case study compares the impact of two prosthetic socket designs, a "traditional" transhumeral (TH) socket design and a Compression Released Stabilized (CRS) socket. A CRS socket was compared to the existing socket of two persons with transhumeral amputation. Comparisons included assessments of patient comfort and satisfaction with fit, as well as dynamic kinematic assessment using a novel high-speed, high-resolution, bi-plane video radiography system (XROMM, for X-ray Reconstruction of Moving Morphology). Subjects were more satisfied with the comfort of the traditional sockets, although they had positive impressions about aspects of the fit and style of the CRS socket, and thought that it provided better control. Dynamic kinematic assessment revealed that the CRS socket provided better control of the residual limb within the socket, and had less slippage as compared to a traditional TH socket design. The TH CRS socket provided better control of the residual limb within the socket, and had less slippage. However, participants were less satisfied with the comfort and overall utility of the CRS socket, and stated that additional fitting visits/modifications to the CRS socket were needed. It is possible that satisfaction with the CRS socket may have improved with prosthetic adjustment and more acclimation time. Implications for Rehabilitation A comfortable, good fitting prosthetic socket is the key factor in determining how long (or if) an upper limb amputee can tolerate wearing a prosthesis. This case series was a comparison of two socket designs, a 'traditional' socket design and a Compression Released Stabilized (CRS) socket design in persons with transhumeral amputation. The CRS socket provided better control of the residual limb within the socket, and had less slippage. However, its tightness made it more difficult to don. Both subjects were less satisfied with the comfort and overall utility of the CRS socket. However, satisfaction might have been improved with additional fitting visits and more acclimation time.
Programmable Automated Welding System (PAWS)
NASA Technical Reports Server (NTRS)
Kline, Martin D.
1994-01-01
An ambitious project to develop an advanced, automated welding system is being funded as part of the Navy Joining Center with Babcock & Wilcox as the prime integrator. This program, the Programmable Automated Welding System (PAWS), involves the integration of both planning and real-time control activities. Planning functions include the development of a graphical decision support system within a standard, portable environment. Real-time control functions include the development of a modular, intelligent, real-time control system and the integration of a number of welding process sensors. This paper presents each of these components of the PAWS and discusses how they can be utilized to automate the welding operation.
Strategic Alliances: Making a Difference One Warfighter At a Time
2011-03-12
Prototype Integration Planning Machining / CNC / Metals Welding Assembly / Paint Integration •Field-Experienced Veterans •Component, Subsystems...Wiring Harness •CAD/CAM CNC Programming •Quick reaction of parts - CNC , Lathes, Mills, Water Jet/Laser Cutting Design •Mechanical, Electrical...DEFORMATION RESISTANCE WELDING • Tubular Structural welding, Light weight structures COMBINED PLASMA -MIG ARC WELDING • Faster than any other
Zadeh, Homayoun H; Abdelhamid, Alaa; Omran, Mostafa; Bakhshalian, Neema; Tarnow, Dennis
2016-06-01
The aims of this study were to evaluate (i) the efficacy of ridge preservation and repair involving SocketKAP(™) and SocketKAGE(™) devices following tooth removal; and (ii) ridge contour changes at 6 months post-extraction in intact sockets and sockets with dehiscence defects. Thirty-six patients required a total of 61 teeth to be extracted. Five cohorts were established with groups A-C involving intact sockets and groups D and E involving facial dehiscence: (A) Negative Control; (B) SocketKAP(™) alone; (C) Anorganic Bovine Bone Mineral (ABBM) + SocketKAP(™) ; (D) Negative Control; and (E) ABBM + SocketKAP(™) + SocketKAGE(™) . Preoperative CBCT and laser-scanned casts were obtained. Teeth segmented from preoperative CBCT were merged with study cast images to allow for digital removal of teeth from the casts. Volumetric measurements of ridge contour were performed. Images of preoperative and 6 months post-operative casts were superimposed to measure ridge contour changes. Post-extraction contour loss occurred in all sockets primarily in the crestal 3 mm but was also detected up to 6 mm from alveolar crest. For intact sockets, SocketKAP(™) or SocketKAP(™) + ABBM interventions led to greater percentages of remaining ridge contour when compared to controls. A significant difference favoring SocketKAP(™) + SocketKAGE(™) + ABBM treatment was observed for sockets with facial dehiscence when compared to controls. SocketKAP(™) , with or without ABBM, significantly limited post-extraction ridge contour loss in intact sockets. In the absence of a group treated with only the SocketKAGE(™) , it is not possible to determine its efficacy, although the combination of SocketKAGE(™) + SocketKAP(™) + ABBM was effective in limiting post-extraction ridge contour loss in sockets with dehiscence defects. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Koutouzis, Theofilos; Lipton, David
2016-01-01
The aim of this study was to evaluate the necessity for additional regenerative procedures following healing of compromised and noncompromised extraction sockets with alveolar ridge preservation procedures through the use of virtual implant imaging software. The cohort was comprised of 87 consecutive patients subjected to a single maxillary tooth extraction with an alveolar ridge preservation procedure for subsequent implant placement. Patients were divided into two main groups based on the integrity of the buccal bone plate following teeth extraction. Patients in the compromised socket (CS) group (n = 52) had partial or complete buccal bone plate loss, and patients in the noncompromised socket (NCS) group (n = 35) exhibited no bone loss of their socket walls following tooth extraction. Following 4 to 6 months of healing, all patients had a cone beam computed tomography (CBCT) study. Root-formed implants were placed virtually in an ideal prosthetic position. The number of implants per group and location (anterior, premolar, molar) exhibiting exposed buccal implant surface was calculated. In the CS group, 5 out of 19 anterior implants (26.3%), 4 out of 14 premolar implants (28.5%), and 7 out of 19 molar implants (36.8%) had exposed buccal surfaces. In the NCS group, 4 out of 9 anterior implants (44.4%), 2 out of 9 premolar implants (22.2%), and 4 out of 17 molar implants (23.5%) had exposed buccal surfaces. There were no statistically significant differences for intragroup and intergroup comparisons (χ² test, P > .05). This study failed to find statistically significant differences in the frequency of implants with exposed buccal surfaces placed virtually, following treatment of compromised and noncompromised sockets. A high proportion (22% to 44%) of sites had implants that potentially needed additional regenerative procedures.
Effects of Socket Size on Metrics of Socket Fit in Trans-Tibial Prosthesis Users
Sanders, Joan E; Youngblood, Robert T; Hafner, Brian J; Cagle, John C; McLean, Jake B; Redd, Christian B; Dietrich, Colin R; Ciol, Marcia A; Allyn, Katheryn J
2017-01-01
The purpose of this research was to conduct a preliminary effort to identify quantitative metrics to distinguish a good socket from an oversized socket in people with trans-tibial amputation. Results could be used to inform clinical practices related to socket replacement. A cross-over study was conducted on community ambulators (K-level 3 or 4) with good residual limb sensation. Participants were each provided with two sockets, a duplicate of their as-prescribed socket and a modified socket that was enlarged or reduced by 1.8 mm (~6% of the socket volume) based on the fit quality of the as-prescribed socket. The two sockets were termed a larger socket and a smaller socket. Activity was monitored while participants wore each socket for 4wk. Participants’ gait; self-reported satisfaction, quality of fit, and performance; socket comfort; and morning-to-afternoon limb fluid volume changes were assessed. Visual analysis of plots and estimated effect sizes (measure as mean difference divided by standard deviation) showed largest effects for step time asymmetry, step width asymmetry, anterior and anterior-distal morning-to-afternoon fluid volume change, socket comfort scores, and self-reported measures of utility, satisfaction, and residual limb health. These variables may be viable metrics for early detection of deterioration in socket fit, and should be tested in a larger clinical study. PMID:28373013
Effects of socket size on metrics of socket fit in trans-tibial prosthesis users.
Sanders, Joan E; Youngblood, Robert T; Hafner, Brian J; Cagle, John C; McLean, Jake B; Redd, Christian B; Dietrich, Colin R; Ciol, Marcia A; Allyn, Katheryn J
2017-06-01
The purpose of this research was to conduct a preliminary effort to identify quantitative metrics to distinguish a good socket from an oversized socket in people with trans-tibial amputation. Results could be used to inform clinical practices related to socket replacement. A cross-over study was conducted on community ambulators (K-level 3 or 4) with good residual limb sensation. Participants were each provided with two sockets, a duplicate of their as-prescribed socket and a modified socket that was enlarged or reduced by 1.8mm (∼6% of the socket volume) based on the fit quality of the as-prescribed socket. The two sockets were termed a larger socket and a smaller socket. Activity was monitored while participants wore each socket for 4 weeks. Participants' gait; self-reported satisfaction, quality of fit, and performance; socket comfort; and morning-to-afternoon limb fluid volume changes were assessed. Visual analysis of plots and estimated effect sizes (measured as mean difference divided by standard deviation) showed largest effects for step time asymmetry, step width asymmetry, anterior and anterior-distal morning-to-afternoon fluid volume change, socket comfort score, and self-reported utility. These variables may be viable metrics for early detection of deterioration in socket fit, and should be tested in a larger clinical study. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.
Fatone, Stefania; Caldwell, Ryan
2017-06-01
Current transfemoral prosthetic sockets are problematic as they restrict function, lack comfort, and cause residual limb problems. Development of a subischial socket with lower proximal trim lines is an appealing way to address this problem and may contribute to improving quality of life of persons with transfemoral amputation. The purpose of this study was to illustrate the use of a new subischial socket in two subjects. Case series. Two unilateral transfemoral prosthesis users participated in preliminary socket evaluations comparing functional performance of the new subischial socket to ischial containment sockets. Testing included gait analysis, socket comfort score, and performance-based clinical outcome measures (Rapid-Sit-To-Stand, Four-Square-Step-Test, and Agility T-Test). For both subjects, comfort was better in the subischial socket, while gait and clinical outcomes were generally comparable between sockets. While these evaluations are promising regarding the ability to function in this new socket design, more definitive evaluation is needed. Clinical relevance Using gait analysis, socket comfort score and performance-based outcome measures, use of the Northwestern University Flexible Subischial Vaccum Socket was evaluated in two transfemoral prosthesis users. Socket comfort improved for both subjects with comparable function compared to ischial containment sockets.
Computer-socket manufacturing error: How much before it is clinically apparent?
Sanders, Joan E.; Severance, Michael R.; Allyn, Kathryn J.
2015-01-01
The purpose of this research was to pursue quality standards for computer-manufacturing of prosthetic sockets for people with transtibial limb loss. Thirty-three duplicates of study participants’ normally used sockets were fabricated using central fabrication facilities. Socket-manufacturing errors were compared with clinical assessments of socket fit. Of the 33 sockets tested, 23 were deemed clinically to need modification. All 13 sockets with mean radial error (MRE) greater than 0.25 mm were clinically unacceptable, and 11 of those were deemed in need of sizing reduction. Of the remaining 20 sockets, 5 sockets with interquartile range (IQR) greater than 0.40 mm were deemed globally or regionally oversized and in need of modification. Of the remaining 15 sockets, 5 sockets with closed contours of elevated surface normal angle error (SNAE) were deemed clinically to need shape modification at those closed contour locations. The remaining 10 sockets were deemed clinically acceptable and not in need modification. MRE, IQR, and SNAE may serve as effective metrics to characterize quality of computer-manufactured prosthetic sockets, helping facilitate the development of quality standards for the socket manufacturing industry. PMID:22773260
NASA Technical Reports Server (NTRS)
Bayless, E. O.; Lawless, K. G.; Kurgan, C.; Nunes, A. C.; Graham, B. F.; Hoffman, D.; Jones, C. S.; Shepard, R.
1993-01-01
Fully automated variable-polarity plasma arc VPPA welding system developed at Marshall Space Flight Center. System eliminates defects caused by human error. Integrates many sensors with mathematical model of the weld and computer-controlled welding equipment. Sensors provide real-time information on geometry of weld bead, location of weld joint, and wire-feed entry. Mathematical model relates geometry of weld to critical parameters of welding process.
Design of a novel prosthetic socket: assessment of the thermal performance.
Webber, Christina M; Davis, Brian L
2015-05-01
Prosthetic liners and sockets insulate the residual limb, causing excessive sweating and concomitant skin maceration. When coupled with atypical loading conditions, further dermatologic problems can arise. This can significantly reduce the quality of life of an amputee patient. Improving the design of the prosthetic socket has been proposed as a means of reestablishing a normal thermal environment around the residual limb. In this study, a prosthetic socket was modified by incorporating a helical cooling channel within the socket wall using additive manufacturing techniques. Two sockets were modeled: a control socket, and a modified socket containing a 0.48 cm diameter cooling channel. Computer simulations and bench-top testing were used to assess the design's ability to create a greater temperature differential across the socket wall. A greater temperature drop across the socket wall suggested that the socket could provide cooling benefits to the residual limb by allowing for heat to be drawn away from the limb. The temperature difference across the socket wall was calculated for both sockets in each aspect of the study. Both socket type (p=0.002) and location on the socket (p=0.014) were statistically significant factors affecting the temperature difference between inner and outer socket walls. Compared with the control socket, the modified socket containing a helical cooling channel exhibited greater temperature differences across its wall of 11.1 °C and 6.4 °C in the computer simulations and bench-top testing, respectively. This finding suggested that socket modifications, such as the cooling channel presented, could provide a beneficial cooling effect to an amputee patient's residual limb. Copyright © 2015 Elsevier Ltd. All rights reserved.
Gerschutz, Maria J; Haynes, Michael L; Nixon, Derek M; Colvin, James M
2011-01-01
Prosthetic sockets serve as the interface between people with amputations and their prostheses. Although most materials used to make prosthetic sockets have been used for many years, knowledge of these materials' properties is limited, especially after they are subjected to fabrication processes. This study evaluated tensile and impact properties of the current state-of-the-art materials used to fabricate prosthetic check sockets, copolymer sockets, and definitive laminated sockets. Thermolyn Rigid and Orfitrans Stiff check socket materials produced significantly lower tensile strength and impact resistance than polyethylene terephthalate glycol (PETG). Copolymer socket materials exhibited greater resistance to impact forces than the check socket materials but lower tensile strengths than PETG. The heated molding processes, for the check socket and copolymer materials, reduced both tensile strength and elongation at break. Definitive laminated sockets were sorted according to fabrication techniques. Nyglass material had significantly higher elongation, indicating a more ductile material than carbon-based laminations. Carbon sockets with pigmented resin had higher tensile strength and modulus at break than nonpigmented carbon sockets. Elongation at yield and elongation at break were similar for both types of carbon-based laminations. The material properties determined in this study provide a foundation for understanding and improving the quality of prosthetic sockets using current fabrication materials and a basis for evaluating future technologies.
Fatone, Stefania; Caldwell, Ryan
2017-01-01
Background: Current transfemoral prosthetic sockets are problematic as they restrict function, lack comfort, and cause residual limb problems. Development of a subischial socket with lower proximal trim lines is an appealing way to address this problem and may contribute to improving quality of life of persons with transfemoral amputation. Objectives: The purpose of this study was to illustrate the use of a new subischial socket in two subjects. Study design: Case series. Methods: Two unilateral transfemoral prosthesis users participated in preliminary socket evaluations comparing functional performance of the new subischial socket to ischial containment sockets. Testing included gait analysis, socket comfort score, and performance-based clinical outcome measures (Rapid-Sit-To-Stand, Four-Square-Step-Test, and Agility T-Test). Results: For both subjects, comfort was better in the subischial socket, while gait and clinical outcomes were generally comparable between sockets. Conclusion: While these evaluations are promising regarding the ability to function in this new socket design, more definitive evaluation is needed. Clinical relevance Using gait analysis, socket comfort score and performance-based outcome measures, use of the Northwestern University Flexible Subischial Vaccum Socket was evaluated in two transfemoral prosthesis users. Socket comfort improved for both subjects with comparable function compared to ischial containment sockets. PMID:28132589
Dry Socket Etiology, Diagnosis, and Clinical Treatment Techniques.
Mamoun, John
2018-04-01
Dry socket, also termed fibrinolytic osteitis or alveolar osteitis, is a complication of tooth exodontia. A dry socket lesion is a post-extraction socket that exhibits exposed bone that is not covered by a blood clot or healing epithelium and exists inside or around the perimeter of the socket or alveolus for days after the extraction procedure. This article describes dry socket lesions; reviews the basic clinical techniques of treating different manifestations of dry socket lesions; and shows how microscope level loupe magnification of 6× to 8× or greater, combined with co-axial illumination or a dental operating microscope, facilitate more precise treatment of dry socket lesions. The author examines the scientific validity of the proposed causes of dry socket lesions (such as bacteria, inflammation, fibrinolysis, or traumatic extractions) and the scientific validity of different terminologies used to describe dry socket lesions. This article also presents an alternative model of what causes dry socket lesions, based on evidence from dental literature. Although the clinical techniques for treating dry socket lesions seem empirically correct, more evidence is required to determine the causes of dry socket lesions.
Dry Socket Etiology, Diagnosis, and Clinical Treatment Techniques
2018-01-01
Dry socket, also termed fibrinolytic osteitis or alveolar osteitis, is a complication of tooth exodontia. A dry socket lesion is a post-extraction socket that exhibits exposed bone that is not covered by a blood clot or healing epithelium and exists inside or around the perimeter of the socket or alveolus for days after the extraction procedure. This article describes dry socket lesions; reviews the basic clinical techniques of treating different manifestations of dry socket lesions; and shows how microscope level loupe magnification of 6× to 8× or greater, combined with co-axial illumination or a dental operating microscope, facilitate more precise treatment of dry socket lesions. The author examines the scientific validity of the proposed causes of dry socket lesions (such as bacteria, inflammation, fibrinolysis, or traumatic extractions) and the scientific validity of different terminologies used to describe dry socket lesions. This article also presents an alternative model of what causes dry socket lesions, based on evidence from dental literature. Although the clinical techniques for treating dry socket lesions seem empirically correct, more evidence is required to determine the causes of dry socket lesions. PMID:29732309
Yang, Ying-yang; DU, Sheng-nan; Lv, Zong-kai
2015-08-01
To compare the results of high-speed handpiece and minimally invasive extraction in impacted mandibular third molar extraction. From May 2011 to May 2014, 83 patients undergoing impacted mandibular third molar extraction were enrolled into the study and randomly divided into 2 groups: 42 patients in group A (experimental group) and 41 patients in group B (control group). Group B underwent extraction with traditional method and group A underwent high-speed handpiece and minimally invasive extraction of the impacted mandibular third molar. The occurrences of the root fracture, gingival laceration, tooth mobility, lingual bone plate fracture, jaw fracture and dislocation of temporomandibular joint during operation and lower lip numbness, dry socket, facial swelling and limitation of mouth opening after operation were observed and compared between 2 groups. The operation time, integrity of extraction sockets, VAS pain score and satisfaction from patients were collected and compared. SPSS 19.0 software package was used for statistical analysis. The occurrences of root fracture, gingival laceration, tooth mobility, lingual bone plate fracture, jaw fracture, and dislocation of temporomandibular joint during operation in group A significantly decreased compared with group B (P<0.05). The occurrences of lower lip numbness, dry socket, facial swelling and limitation of mouth opening after operation in group A significantly decreased compared with group B (P<0.05). The operation time, integrity of extraction sockets, VAS pain scores and satisfaction scores in group A improved significantly compared with group B (P<0.05). High-speed handpiece and minimally invasive extraction should be widely used in impacted mandibular third molar extraction, due to the advantages of simple operation, high efficiency, minimal trauma, and few perioperative complications.
Integrated versus non-integrated orbital implants for treating anophthalmic sockets.
Schellini, Silvana; El Dib, Regina; Silva, Leandro Re; Farat, Joyce G; Zhang, Yuqing; Jorge, Eliane C
2016-11-07
Anophthalmia is the absence of one or both eyes, and it can be congenital (i.e. a birth defect) or acquired later in life. There are two main types of orbital implant: integrated, whereby the implant receives a blood supply from the body that allows for the integration of the prosthesis within the tissue; and non-integrated, where the implant remains separate. Despite the remarkable progress in anophthalmic socket reconstruction and in the development of various types of implants, there are still uncertainties about the real roles of integrated (hydroxyapatite (HA), porous polyethylene (PP), composites) and non-integrated (polymethylmethacrylate (PMMA)/acrylic and silicone) orbital implants in anophthalmic socket treatment. To assess the effects of integrated versus non-integrated orbital implants for treating anophthalmic sockets. We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 7), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to August 2016), Embase (January 1980 to August 2016), Latin American and Caribbean Health Sciences Literature Database (LILACS) (1982 to August 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 8 August 2016. Randomised controlled trials (RCTs) and quasi-RCTs of integrated and non-integrated orbital implants for treating anophthalmic sockets. Two authors independently selected relevant trials, assessed methodological quality and extracted data. We included three studies with a total of 284 participants (250 included in analysis). The studies were conducted in India, Iran and the Netherlands. The three studies were clinically heterogenous, comparing different materials and using different surgical techniques. None of the included studies used a peg (i.e. a fixing pin used to connect the implant to the prosthesis). In general the trials were poorly reported, and we judged them to be at unclear risk of bias.One trial compared HA using traditional enucleation versus alloplastic implantation using evisceration (N = 100). This trial was probably not masked. The second trial compared PP with scleral cap enucleation versus PMMA with either myoconjunctival or traditional enucleation (N = 150). Although participants were not masked, outcome assessors were. The last trial compared HA and acrylic using the enucleation technique (N = 34) but did not report comparative effectiveness data.In the trial comparing HA versus alloplastic implantation, there was no evidence of any difference between the two groups with respect to the proportion of successful procedures at one year (risk ratio (RR) 1.02, 95% confidence interval (CI) 0.95 to 1.09, N = 100, low-certainty evidence). People receiving HA had slightly worse horizontal implant mobility compared to the alloplastic group (mean difference (MD) -3.35 mm, 95% CI -4.08 to -2.62, very low-certainty evidence) and slightly worse vertical implant motility (MD -2.76 mm, 95% CI -3.45 to -2.07, very low-certainty evidence). As different techniques were used - enucleation versus evisceration - it is not clear whether these differences in implant motility can be attributed solely to the type of material. Investigators did not report adverse events.In the trial comparing PP versus PMMA, there was no evidence of any difference between the two groups with respect to the proportion of successful procedures at one year (RR 0.92, 95% CI 0.84 to 1.01, N = 150, low-certainty evidence). There was very low-certainty evidence of a difference in horizontal implant motility depending on whether PP was compared to PMMA with traditional enucleation (MD 1.96 mm, 95% CI 1.01 to 2.91) or PMMA with myoconjunctival enucleation (-0.57 mm, 95% CI -1.63 to 0.49). Similarly, for vertical implant motility, there was very low-certainty evidence of a difference in the comparison of PP to PMMA traditional (MD 3.12 mm 95% CI 2.36 to 3.88) but no evidence of a difference when comparing PP to PMMA myoconjunctival (MD -0.20 mm 95% CI -1.28 to 0.88). Four people in the PP group (total N = 50) experienced adverse events (i.e. exposures) compared to 6/100 in the PMMA groups (RR 17.82, 95% CI 0.98 to 324.67, N = 150, very low-certainty evidence).None of the studies reported socket sphere size, cosmetic effect or quality of life measures. Current very low-certainty evidence from three small published randomised controlled trials did not provide sufficient evidence to assess the effect of integrated and non-integrated material orbital implants for treating anophthalmic sockets. This review underlines the need to conduct further well-designed trials in this field.
Electrical grounding prong socket
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leong, R.
1989-09-12
This paper describes a socket for a grounding prong used in a three prong electrical plug. The socket being sufficiently spacious to prevent the socket from significantly stretching when a larger, U-shaped grounding prong is inserted into the socket, and having a ridge to allow a snug fit when a smaller tubular shape grounding prong is inserted into the socket. 11 figs.
Use of Infrared Thermography for the Inspection of Welds in the Shop and Field [Summary
DOT National Transportation Integrated Search
2018-02-01
Steel bridges are created by welding steel components. The quality of these welds is critical to the integrity of the bridge. Weld defects can lead to expensive repairs or mechanical failure. However, weld defects are often below the steel surface an...
NASA Astrophysics Data System (ADS)
Khlusov, I. A.; Khlusova, M. Yu.; Pichugin, V. F.; Sharkeev, Yu. P.; Legostaeva, E. V.
2014-02-01
A relationship between the topography of rough calcium phosphate surfaces having osteogenic niche-reliefs and the electrostatic potential of these surfaces as a possible instrument to control stromal stem cells has been investigated. The in vitro culture of human lung prenatal stromal cells on nanostructured/ultrafine-grained VT1.0 titanium alloy plates with bilateral rough calcium phosphate (CaP) microarc coating was used. It was established that the amplitude of the electret CaP surface potential linearly increased with increasing area of valleys (sockets), and the negative charge is formed on the socket surface. The area of alkaline phosphatase staining (the marker of osteoblast maturation and differentiation) of adherent CD34- CD44+ cells increases linearly with increasing area of artificial microterritory (socket) of the CaP surface occupied with each cell. The negative electret potential in valleys (sockets) of microarc CaP coatings can be the physical mechanism mediating the influence of the surface topography on osteogenic maturation and differentiation of cells in vitro. This mechanism can be called "niche-potential" and can be used as an instrument for biomimetic modification of smooth CaP surfaces to strengthen their integration with the bone tissue.
Ibrahiem, Mohamed F. K.; Abdelaziz, Sahar T. A.
2016-01-01
Purpose. To evaluate a new surgical technique using fascia lata to deepen the shallow inferior conjunctival fornix in contracted socket and anophthalmic socket syndrome. Methods. A prospective controlled study in which 24 sockets of 24 patients who were unable to wear and retain their ocular prosthesis due to shallow inferior fornix were enrolled and categorized into anophthalmic socket syndromes (9 patients) and contracted sockets (15 patients). Another 24 patients who underwent evisceration or enucleation with healthy sockets and can wear and retain their prosthesis comfortably were chosen as a control group. Deepening of the fornix was performed using fascia lata strips under general anesthesia. Central depth of the inferior fornix was measured preoperatively and postoperatively. Results. A statistically significant improvement of the postoperative central inferior fornix depth was reported which was marked in anophthalmic subgroup. 100% of anophthalmic sockets and 93.3% of contracted sockets achieved satisfactory results during the follow-up period with no postoperative lower eyelid malposition or obvious skin scar. Conclusion. Fascia lata technique is a new alternative and effective procedure to deepen the shallow inferior fornix that can be used in moderate to severe contracted sockets or anophthalmic socket syndrome with minimal lower eyelid or socket complications. PMID:27313868
Ibrahiem, Mohamed F K; Abdelaziz, Sahar T A
2016-01-01
Purpose. To evaluate a new surgical technique using fascia lata to deepen the shallow inferior conjunctival fornix in contracted socket and anophthalmic socket syndrome. Methods. A prospective controlled study in which 24 sockets of 24 patients who were unable to wear and retain their ocular prosthesis due to shallow inferior fornix were enrolled and categorized into anophthalmic socket syndromes (9 patients) and contracted sockets (15 patients). Another 24 patients who underwent evisceration or enucleation with healthy sockets and can wear and retain their prosthesis comfortably were chosen as a control group. Deepening of the fornix was performed using fascia lata strips under general anesthesia. Central depth of the inferior fornix was measured preoperatively and postoperatively. Results. A statistically significant improvement of the postoperative central inferior fornix depth was reported which was marked in anophthalmic subgroup. 100% of anophthalmic sockets and 93.3% of contracted sockets achieved satisfactory results during the follow-up period with no postoperative lower eyelid malposition or obvious skin scar. Conclusion. Fascia lata technique is a new alternative and effective procedure to deepen the shallow inferior fornix that can be used in moderate to severe contracted sockets or anophthalmic socket syndrome with minimal lower eyelid or socket complications.
Fatone, Stefania; Caldwell, Ryan
2017-06-01
Current transfemoral prosthetic sockets restrict function, lack comfort, and cause residual limb problems. Lower proximal trim lines are an appealing way to address this problem. Development of a more comfortable and possibly functional subischial socket may contribute to improving quality of life of persons with transfemoral amputation. The purpose of this study was to (1) describe the design and fabrication of a new subischial socket and (2) describe efforts to teach this technique. Development project. Socket development involved defining the following: subject and liner selection, residual limb evaluation, casting, positive mold rectification, check socket fitting, definitive socket fabrication, and troubleshooting of socket fit. Three hands-on workshops to teach the socket were piloted and attended by 30 certified prosthetists and their patient models. Patient models responded positively to the comfort, range of motion, and stability of the new socket while prosthetists described the technique as "straight forward, reproducible." To our knowledge, this is the first attempt to create a teachable subischial socket, and while it appears promising, more definitive evaluation is needed. Clinical relevance We developed the Northwestern University Flexible Subischial Vacuum (NU-FlexSIV) Socket as a more comfortable alternative to current transfemoral sockets and demonstrated that it could be taught successfully to prosthetists.
Global and Local Mechanical Properties of Autogenously Laser Welded Ti-6Al-4V
NASA Astrophysics Data System (ADS)
Cao, Xinjin; Kabir, Abu Syed H.; Wanjara, Priti; Gholipour, Javad; Birur, Anand; Cuddy, Jonathan; Medraj, Mamoun
2014-03-01
Ti-6Al-4V sheets, 3.2-mm in thickness, were butt welded using a continuous wave 4 kW Nd:YAG laser welding system. The effect of two main process parameters, laser power and welding speed, on the joint integrity was characterized in terms of the joint geometry, defects, microstructure, hardness, and tensile properties. In particular, a digital image correlation technique was used to determine the local tensile properties of the welds. It was determined that a wide range of heat inputs can be used to fully penetrate the Ti-6Al-4V butt joints during laser welding. At high laser power levels, however, significant defects such as underfill and porosity, can occur and cause marked degradation in the joint integrity and performance. At low welding speeds, however, significant porosity occurs due to its growth and the potential collapse of instable keyholes. Intermediate to relatively high levels of heat input allow maximization of the joint integrity and performance by limiting the underfill and porosity defects. In considering the effect of the two main defects on the joint integrity, the underfill defect was found to be more damaging to the mechanical performance of the weldment than the porosity. Specifically, it was determined that the maximum tolerable underfill depth for Ti-6Al-4V is approximately 6 pct of the workpiece thickness, which is slightly stricter than the value of 7 pct specified in AWS D17.1 for fusion welding in aerospace applications. Hence, employing optimized laser process parameters allows the underfill depth to be maintained within the tolerable limit (6 pct), which in turn prevents degradation in both the weld strength and ductility. To this end, the ability to maintain weld ductility in Ti-6Al-4V by means of applying a high energy density laser welding process presents a significant advantage over conventional arc welding for the assembly of aerospace components.
Prosthetics socket that incorporates an air splint system focusing on dynamic interface pressure.
Razak, Nasrul Anuar Abd; Osman, Noor Azuan Abu; Gholizadeh, Hossein; Ali, Sadeeq
2014-08-01
The interface pressure between the residual limb and prosthetic socket has a significant effect on an amputee's satisfaction and comfort. This paper presents the design and performance of a new prosthetic socket that uses an air splint system. The air splint prosthetic socket system was implemented by combining the air splint with a pressure sensor that the transhumeral user controls through the use of a microcontroller. The modular construction of the system developed allows the FSR pressure sensors that are placed inside the air splint socket to determine the required size and fitting for the socket used. Fifteen transhumeral amputees participated in the study. The subject's dynamic pressure on the socket that's applied while wearing the air splint systems was recorded using F-socket transducers and microcontroller analysis. The values collected by the F-socket sensor for the air splint prosthetic socket system were determined accordingly by comparing the dynamic pressure applied using statically socket. The pressure volume of the air splint fluctuated and was recorded at an average of 38 kPa (2.5) to 41 kPa (1.3) over three hours. The air splint socket might reduce the pressure within the interface of residual limb. This is particularly important during the daily life activities and may reduce the pain and discomfort at the residual limb in comparison to the static socket. The potential development of an auto-adjusted socket that uses an air splint system as the prosthetic socket will be of interest to researchers involved in rehabilitation engineering, prosthetics and orthotics.
Prosthetics socket that incorporates an air splint system focusing on dynamic interface pressure
2014-01-01
Background The interface pressure between the residual limb and prosthetic socket has a significant effect on an amputee’s satisfaction and comfort. This paper presents the design and performance of a new prosthetic socket that uses an air splint system. Methods The air splint prosthetic socket system was implemented by combining the air splint with a pressure sensor that the transhumeral user controls through the use of a microcontroller. The modular construction of the system developed allows the FSR pressure sensors that are placed inside the air splint socket to determine the required size and fitting for the socket used. Fifteen transhumeral amputees participated in the study. Results The subject’s dynamic pressure on the socket that’s applied while wearing the air splint systems was recorded using F-socket transducers and microcontroller analysis. The values collected by the F-socket sensor for the air splint prosthetic socket system were determined accordingly by comparing the dynamic pressure applied using statically socket. The pressure volume of the air splint fluctuated and was recorded at an average of 38 kPa (2.5) to 41 kPa (1.3) over three hours. Conclusion The air splint socket might reduce the pressure within the interface of residual limb. This is particularly important during the daily life activities and may reduce the pain and discomfort at the residual limb in comparison to the static socket. The potential development of an auto-adjusted socket that uses an air splint system as the prosthetic socket will be of interest to researchers involved in rehabilitation engineering, prosthetics and orthotics. PMID:25085005
29 CFR Appendix II to Part 1918 - Tables for Selected Miscellaneous Auxiliary Gear (Mandatory)
Code of Federal Regulations, 2010 CFR
2010-07-01
... (IWRC), use vales in HT (FC) columns. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Note: (1... HT columns of Table 3. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Notes: (1) These... values in HT columns of Table 3. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Note: (1) These...
29 CFR Appendix II to Part 1918 - Tables for Selected Miscellaneous Auxiliary Gear (Mandatory)
Code of Federal Regulations, 2014 CFR
2014-07-01
... (IWRC), use vales in HT (FC) columns. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Note: (1... HT columns of Table 3. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Notes: (1) These... values in HT columns of Table 3. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Note: (1) These...
29 CFR Appendix II to Part 1918 - Tables for Selected Miscellaneous Auxiliary Gear (Mandatory)
Code of Federal Regulations, 2012 CFR
2012-07-01
... (IWRC), use vales in HT (FC) columns. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Note: (1... HT columns of Table 3. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Notes: (1) These... values in HT columns of Table 3. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Note: (1) These...
29 CFR Appendix II to Part 1918 - Tables for Selected Miscellaneous Auxiliary Gear (Mandatory)
Code of Federal Regulations, 2011 CFR
2011-07-01
... (IWRC), use vales in HT (FC) columns. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Note: (1... HT columns of Table 3. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Notes: (1) These... values in HT columns of Table 3. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Note: (1) These...
29 CFR Appendix II to Part 1918 - Tables for Selected Miscellaneous Auxiliary Gear (Mandatory)
Code of Federal Regulations, 2013 CFR
2013-07-01
... (IWRC), use vales in HT (FC) columns. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Note: (1... HT columns of Table 3. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Notes: (1) These... values in HT columns of Table 3. MS=Mechanical Splice. S=Poured Socket or Swaged Socket. Note: (1) These...
Physical and cognitive effects of virtual reality integrated training.
Stone, Richard T; Watts, Kristopher P; Zhong, Peihan; Wei, Chen-Shuang
2011-10-01
The objective of this study was to evaluate the cognitive and physical impact of virtual reality (VR) integrated training versus traditional training methods in the domain of weld training. Weld training is very important in various industries and represents a complex skill set appropriate for advanced training intervention. As such, there has been a long search for the most successful and most cost-effective method for training new welders. Participants in this study were randomly assigned to one of two separate training courses taught by sanctioned American Welding Society certified welding instructors; the duration of each course was 2 weeks. After completing the training for a specific weld type, participants were given the opportunity to test for the corresponding certification. Participants were evaluated in terms of their cognitive and physical parameters, total training time exposure, and welding certification awards earned. Each of the four weld types taught in this study represented distinct levels of difficulty and required the development of specialized knowledge and skills. This study demonstrated that participants in the VR integrated training group (VR50) performed as well as, and in some cases, significantly outperformed, the traditional welding (TW) training group.The VR50 group was found to have a 41.6% increase in overall certifications earned compared with the TW group. VR technology is a valuable tool for the production of skilled welders in a shorter time and often with more highly developed skills than their traditionally trained counterparts. These findings strongly support the use ofVR integrated training in the welding industry.
Electrical grounding prong socket
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leong, R.
1990-01-01
The invention is a socket for a grounding prong used in a three prong electrical plug and a receptacle for the three prong plug. The socket being sufficiently spacious to prevent the socket from significantly stretching when a larger, U-shaped grounding prong is inserted into the socket, and having a ridge to allow a snug fit when a smaller tubular shape grounding prong is inserted into the socket. 17 figs.
Electrical grounding prong socket
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leong, R.
1990-12-31
The invention is a socket for a grounding prong used in a three prong electrical plug and a receptacle for the three prong plug. The socket being sufficiently spacious to prevent the socket from significantly stretching when a larger, U-shaped grounding prong is inserted into the socket, and having a ridge to allow a snug fit when a smaller tubular shape grounding prong is inserted into the socket. 17 figs.
Electrical grounding prong socket
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leong, R.
1991-06-18
This patent describes a socket for a grounding prong used in a three prong electrical plug and a receptacle for the three prong plug. The socket being sufficiently spacious to prevent the socket from significantly stretching when a larger, U-shaped grounding prong is inserted into the socket, and having a ridge to allow a snug fit when a smaller tubular shape grounding prong is inserted into the socket.
Electrical grounding prong socket
Leong, Robert
1991-01-01
The invention is a socket for a grounding prong used in a three prong electrical plug and a receptacle for the three prong plug. The socket being sufficiently spacious to prevent the socket from significantly stretching when a larger, U-shaped grounding prong is inserted into the socket, and having a ridge to allow a snug fit when a smaller tubular shape grounding prong is inserted into the socket.
Oxy-Fuel Cutting/Welding. Welding Module 3. Instructor's Guide.
ERIC Educational Resources Information Center
Missouri Univ., Columbia. Instructional Materials Lab.
This guide is intended to assist vocational educators in teaching a four-unit module in oxy-fuel cutting and welding. The module is part of a welding curriculum that has been designed to be totally integrated with Missouri's Vocational Instruction Management System. The following topics are covered in the module: oxyacetylene welding, oxyacetylene…
Basic Welding Skills. Welding Module 1. Instructor's Guide.
ERIC Educational Resources Information Center
Missouri Univ., Columbia. Instructional Materials Lab.
This guide is intended to assist vocational educators in teaching a six-unit module in basic welding skills. The module is part of a welding curriculum that has been designed to be totally integrated with Missouri's Vocational Instruction Management System. The following topics are covered in the module: the welding profession, personal safety,…
Wernke, Matthew M; Schroeder, Ryan M; Haynes, Michael L; Nolt, Lonnie L; Albury, Alexander W; Colvin, James M
2017-07-01
Objective: Prosthetic sockets are custom made for each amputee, yet there are no quantitative tools to determine the appropriateness of socket fit. Ensuring a proper socket fit can have significant effects on the health of residual limb soft tissues and overall function and acceptance of the prosthetic limb. Previous work found that elevated vacuum pressure data can detect movement between the residual limb and the prosthetic socket; however, the correlation between the two was specific to each user. The overall objective of this work is to determine the relationship between elevated vacuum pressure deviations and prosthetic socket fit. Approach: A tension compression machine was used to apply repeated controlled forces onto a residual limb model with sockets of different internal volume. Results: The vacuum pressure-displacement relationship was dependent on socket fit. The vacuum pressure data were sensitive enough to detect differences of 1.5% global volume and can likely detect differences even smaller. Limb motion was reduced as surface area of contact between the limb model and socket was maximized. Innovation: The results suggest that elevated vacuum pressure data provide information to quantify socket fit. Conclusions: This study provides evidence that the use of elevated vacuum pressure data may provide a method for prosthetists to quantify and monitor socket fit. Future studies should investigate the relationship between socket fit, limb motion, and limb health to define optimal socket fit parameters.
Comparison of Rectified and Unrectified Sockets for Transtibial Amputees.
Engsberg, Jack R; Sprouse, S Wayne; Uhrich, Mary L; Ziegler, Barbara R; Luitjohan, F Daniel
2008-01-01
The current method for fabricating prosthetic sockets is to modify a positive mold to account for the non-homogeneity of the residual limb to tolerate load (i.e., rectified socket). We tested unrectified sockets by retaining the shape of the residual limb, except for a distal end pad, using an alginate gel process instead of casting. This investigation compared rectified and unrectified sockets. Forty-three adults with unilateral transtibial amputations were tested after randomly wearing both rectified and unrectified sockets for at least 4 weeks. Testing included a gait analysis, energy expenditure and Prosthesis Evaluation Questionnaire (PEQ). Results indicated no differences between sockets for gait speed and timing, gait kinematics and kinetics, and gait energy expenditure. There were also no differences in the Prosthetic Evaluation Questionnaire and 16 subjects selected the rectified socket, 25 selected the unrectified socket, and 2 subjects selected to use both sockets as their exit socket. Results seemed to indicate that more than one paradigm exists for shaping prosthetic sockets, and this paradigm may be helpful in understanding the mechanisms of socket fit. The alginate gel fabrication method was simpler than the traditional method. The method could be helpful in other countries where prosthetic care is lacking, may be helpful with new amputees, and may be helpful in typical clinics to reduce costs and free the prosthetist to focus more time on patient needs.
Comparison of Rectified and Unrectified Sockets for Transtibial Amputees
Engsberg, Jack R.; Sprouse, S. Wayne; Uhrich, Mary L.; Ziegler, Barbara R.; Luitjohan, F. Daniel
2008-01-01
The current method for fabricating prosthetic sockets is to modify a positive mold to account for the non-homogeneity of the residual limb to tolerate load (i.e., rectified socket). We tested unrectified sockets by retaining the shape of the residual limb, except for a distal end pad, using an alginate gel process instead of casting. This investigation compared rectified and unrectified sockets. Forty-three adults with unilateral transtibial amputations were tested after randomly wearing both rectified and unrectified sockets for at least 4 weeks. Testing included a gait analysis, energy expenditure and Prosthesis Evaluation Questionnaire (PEQ). Results indicated no differences between sockets for gait speed and timing, gait kinematics and kinetics, and gait energy expenditure. There were also no differences in the Prosthetic Evaluation Questionnaire and 16 subjects selected the rectified socket, 25 selected the unrectified socket, and 2 subjects selected to use both sockets as their exit socket. Results seemed to indicate that more than one paradigm exists for shaping prosthetic sockets, and this paradigm may be helpful in understanding the mechanisms of socket fit. The alginate gel fabrication method was simpler than the traditional method. The method could be helpful in other countries where prosthetic care is lacking, may be helpful with new amputees, and may be helpful in typical clinics to reduce costs and free the prosthetist to focus more time on patient needs. PMID:18776945
Change in residual limb size over time in the NU-FlexSIV socket: A case study.
Fatone, Stefania; Yohay, Jessica; Caldwell, Ryan
2018-05-01
This case study represented a unique opportunity wherein a long-time user of sub-ischial sockets had kept nearly every socket he wore for a decade. This individual let us borrow these sockets so we could digitize them and indirectly assess change in residual limb size over time by calculating changes in socket volume and circumferences over time. Case Description and Methods: Over a decade, the subject maintained a relatively stable body weight of 84-88 kg and received nine sub-ischial sockets. The internal surface of each socket was scanned using a mechanical digitizer and volume and circumferences calculated. Findings and Outcomes: Socket volume increased 31.3%, from a low of 2659.2 cm 3 for the oldest socket to a high of 3490.6 cm 3 for the most recent socket. Proximal circumferences increased more than distal circumferences with a 15.9% total increase proximally versus 8.9% total increase distally. The results suggest that this individual's residual limb increased in size over time despite the compressive effect of the socket and liner. In addition, the increase in circumference was greater proximally than distally, which is where the remaining muscle bellies are located. Clinical relevance This case study provides insight into the long-term effect of the sub-ischial socket on residual limb volume given compression of the soft tissues by the socket system.
Fatone, Stefania; Caldwell, Ryan
2017-01-01
Background: Current transfemoral prosthetic sockets restrict function, lack comfort, and cause residual limb problems. Lower proximal trim lines are an appealing way to address this problem. Development of a more comfortable and possibly functional subischial socket may contribute to improving quality of life of persons with transfemoral amputation. Objectives: The purpose of this study was to (1) describe the design and fabrication of a new subischial socket and (2) describe efforts to teach this technique. Study design: Development project. Methods: Socket development involved defining the following: subject and liner selection, residual limb evaluation, casting, positive mold rectification, check socket fitting, definitive socket fabrication, and troubleshooting of socket fit. Three hands-on workshops to teach the socket were piloted and attended by 30 certified prosthetists and their patient models. Results: Patient models responded positively to the comfort, range of motion, and stability of the new socket while prosthetists described the technique as “straight forward, reproducible.” Conclusion: To our knowledge, this is the first attempt to create a teachable subischial socket, and while it appears promising, more definitive evaluation is needed. Clinical relevance We developed the Northwestern University Flexible Subischial Vacuum (NU-FlexSIV) Socket as a more comfortable alternative to current transfemoral sockets and demonstrated that it could be taught successfully to prosthetists. PMID:28094686
On-orbit NDE: A novel approach to tube weld inspection
NASA Technical Reports Server (NTRS)
Michaels, Kerry; Hughes, Greg
1994-01-01
The challenge of fabrication and repair of structures in space must be met if we are to utilize and maintain long-duration space facilities. Welding techniques have been demonstrated to provide the most reliable means to accomplish this task. Over the past few years, methods have been developed to perform orbital tube welding employing space-based welding technology pioneered by the former Soviet Union. Welding can result in the formation of defects, which threaten the structural integrity of the welded joint. Implementation of welding on-orbit, therefore, must also include methods to evaluate the quality and integrity of the welded joints. To achieve this goal, the development of an on-orbit tube weld inspection system, utilizing alternating current field measurement (ACFM) technology, has been under taken. This paper describes the development of the ACFM on-orbit tube weld inspection tool. Topics discussed include: requirements for on-orbit NDE, basic theory of ACFM, its advantages over other NDE methods for on-orbit applications, and the ACFM NDE system design. System operation and trial inspection results are also discussed. Future work with this technology is also considered.
An integrated optical sensor for GMAW feedback control
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taylor, P.L.; Watkins, A.D.; Larsen, E.D.
1992-08-01
The integrated optical sensor (IOS) is a multifunction feedback control sensor for arc welding, that is computer automated and independent of significant operator interaction. It is based on three major ``off-the-shelf`` components: a charged coupled device (CCD) camera, a diode laser, and a processing computer. The sensor head is compact and lightweight to avoid interference with weld head mobility, hardened to survive the harsh operating environment, and free of specialized cooling and power requirements. The sensor is positioned behind the GMAW torch and measures weld pool position and width, standoff distance, and postweld centerline cooling rate. Weld pool position andmore » width are used in a feedback loop, by the weld controller, to track the weld pool relative to the weld joint, thus allowing compensation for such phenomena as arc blow. Sensor stand off distance is used in a feedback loop to control the contact tip to base metal distance during the welding process. Cooling rate information is used to infer the final metallurgical state of the weld bead and heat affected zone, thereby providing a means of controlling post weld mechanical properties.« less
An integrated optical sensor for GMAW feedback control
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taylor, P.L.; Watkins, A.D.; Larsen, E.D.
1992-01-01
The integrated optical sensor (IOS) is a multifunction feedback control sensor for arc welding, that is computer automated and independent of significant operator interaction. It is based on three major off-the-shelf'' components: a charged coupled device (CCD) camera, a diode laser, and a processing computer. The sensor head is compact and lightweight to avoid interference with weld head mobility, hardened to survive the harsh operating environment, and free of specialized cooling and power requirements. The sensor is positioned behind the GMAW torch and measures weld pool position and width, standoff distance, and postweld centerline cooling rate. Weld pool position andmore » width are used in a feedback loop, by the weld controller, to track the weld pool relative to the weld joint, thus allowing compensation for such phenomena as arc blow. Sensor stand off distance is used in a feedback loop to control the contact tip to base metal distance during the welding process. Cooling rate information is used to infer the final metallurgical state of the weld bead and heat affected zone, thereby providing a means of controlling post weld mechanical properties.« less
Review of the socket design and interface pressure measurement for transtibial prosthesis.
Pirouzi, Gh; Abu Osman, N A; Eshraghi, A; Ali, S; Gholizadeh, H; Wan Abas, W A B
2014-01-01
Socket is an important part of every prosthetic limb as an interface between the residual limb and prosthetic components. Biomechanics of socket-residual limb interface, especially the pressure and force distribution, have effect on patient satisfaction and function. This paper aimed to review and evaluate studies conducted in the last decades on the design of socket, in-socket interface pressure measurement, and socket biomechanics. Literature was searched to find related keywords with transtibial amputation, socket-residual limb interface, socket measurement, socket design, modeling, computational modeling, and suspension system. In accordance with the selection criteria, 19 articles were selected for further analysis. It was revealed that pressure and stress have been studied in the last decaeds, but quantitative evaluations remain inapplicable in clinical settings. This study also illustrates prevailing systems, which may facilitate improvements in socket design for improved quality of life for individuals ambulating with transtibial prosthesis. It is hoped that the review will better facilitate the understanding and determine the clinical relevance of quantitative evaluations.
Review of the Socket Design and Interface Pressure Measurement for Transtibial Prosthesis
Pirouzi, Gh.; Abu Osman, N. A.; Eshraghi, A.; Ali, S.; Gholizadeh, H.; Wan Abas, W. A. B.
2014-01-01
Socket is an important part of every prosthetic limb as an interface between the residual limb and prosthetic components. Biomechanics of socket-residual limb interface, especially the pressure and force distribution, have effect on patient satisfaction and function. This paper aimed to review and evaluate studies conducted in the last decades on the design of socket, in-socket interface pressure measurement, and socket biomechanics. Literature was searched to find related keywords with transtibial amputation, socket-residual limb interface, socket measurement, socket design, modeling, computational modeling, and suspension system. In accordance with the selection criteria, 19 articles were selected for further analysis. It was revealed that pressure and stress have been studied in the last decaeds, but quantitative evaluations remain inapplicable in clinical settings. This study also illustrates prevailing systems, which may facilitate improvements in socket design for improved quality of life for individuals ambulating with transtibial prosthesis. It is hoped that the review will better facilitate the understanding and determine the clinical relevance of quantitative evaluations. PMID:25197716
Safari, Mohammad Reza; Tafti, Nahid; Aminian, Gholamreza
2015-01-01
The objectives of the current study were to compare intra-socket pressure differences between comfortable and uncomfortable socket conditions, and the usefulness of subject perception of satisfaction, activity limitations, and socket comfort in distinguishing between these two socket conditions. Five unilateral trans-tibial amputees took part in the study. They answered the Socket Comfort Score (SCS) and Trinity Amputation and Prosthetic Experience Scale (TAPES) questionnaires before the interface pressure (in standing and walking) was measured for the uncomfortable socket condition at five regions of the residual limb. Participants were then provided with a comfortable socket and wore it for two weeks. Participants who were satisfied with the socket fit after two weeks repeated the SCS and TAPES questionnaires and interface pressure measurements. The differences between the test results of the two conditions were not statistically significant, except for the interface pressure at the popliteal region during the early stance phase, TAPES socket fit subscale, and the SCS. Due to large variability of the data and the lack of statistical significance, no firm conclusion can be made on the possible relationship between the interface pressure values and the patient-reported outcomes of the two socket conditions. A larger sample size and longer acclimation period are required to locate significant differences.
Computerized adaptive control weld skate with CCTV weld guidance project
NASA Technical Reports Server (NTRS)
Wall, W. A.
1976-01-01
This report summarizes progress of the automatic computerized weld skate development portion of the Computerized Weld Skate with Closed Circuit Television (CCTV) Arc Guidance Project. The main goal of the project is to develop an automatic welding skate demonstration model equipped with CCTV weld guidance. The three main goals of the overall project are to: (1) develop a demonstration model computerized weld skate system, (2) develop a demonstration model automatic CCTV guidance system, and (3) integrate the two systems into a demonstration model of computerized weld skate with CCTV weld guidance for welding contoured parts.
Integration of NASA-sponsored studies on aluminum welding
NASA Technical Reports Server (NTRS)
Masubuchi, K.
1972-01-01
The results are presented of numerous studies relating to aluminum alloy welding. The subjects covered include: (1) effects of porosity on weld joint performance, (2) sources of porosity, (3) weld thermal effects, (4) residual stresses and distortion, and (5) manufacturing process system control.
Two degree of freedom camera mount
NASA Technical Reports Server (NTRS)
Ambrose, Robert O. (Inventor)
2003-01-01
A two degree of freedom camera mount. The camera mount includes a socket, a ball, a first linkage and a second linkage. The socket includes an interior surface and an opening. The ball is positioned within an interior of the socket. The ball includes a coupling point for rotating the ball relative to the socket and an aperture for mounting a camera. The first and second linkages are rotatably connected to the socket and slidably connected to the coupling point of the ball. Rotation of the linkages with respect to the socket causes the ball to rotate with respect to the socket.
NASA Technical Reports Server (NTRS)
Barry, Matthew R.
2006-01-01
The X-Windows Socket Widget Class ("Class" is used here in the object-oriented-programming sense of the word) was devised to simplify the task of implementing network connections for graphical-user-interface (GUI) computer programs. UNIX Transmission Control Protocol/Internet Protocol (TCP/IP) socket programming libraries require many method calls to configure, operate, and destroy sockets. Most X Windows GUI programs use widget sets or toolkits to facilitate management of complex objects. The widget standards facilitate construction of toolkits and application programs. The X-Windows Socket Widget Class encapsulates UNIX TCP/IP socket-management tasks within the framework of an X Windows widget. Using the widget framework, X Windows GUI programs can treat one or more network socket instances in the same manner as that of other graphical widgets, making it easier to program sockets. Wrapping ISP socket programming libraries inside a widget framework enables a programmer to treat a network interface as though it were a GUI.
Mahesh, Lanka; Narayan, Tv; Kostakis, Georgios; Shukla, Sagrika
2014-03-01
To measure implant stability using periotest values of implants placed in sockets augmented with calcium phospho-silicate putty (CPS Putty) as compared with implant stability in naturally healed sockets. Twenty two sockets were implanted with CPS Putty immediately after extraction. The sockets were re-entered after a healing period at 5 to 6 months (average 5.3 months) for implant placement. Periotest values were recorded during implant insertion to assess primary stability. These were compared with the Periotest values of 26 implants placed in 22 patients, with naturally healed sockets. Periotest values were significantly lower in the grafted group, indicating better implant stability in sites grafted with CPS putty. Implant stability seems to be significantly higher in sockets augmented using CPS putty when compared to nongrafted sites. This suggests that socket grafting with CPS putty may enhance the quality of available bone for implantation.
Gerschutz, Maria J; Haynes, Michael L; Nixon, Derek; Colvin, James M
2012-01-01
A prosthesis encounters loading through forces and torques exerted by the person with amputation. International Organization for Standardization (ISO) standard 10328 was designed to test most lower-limb prosthetic components. However, this standard does not include prosthetic sockets. We measured static failure loads of prosthetic sockets using a modified ISO 10328 and then compared them with the criteria set by this standard for other components. Check socket (CS) strengths were influenced by thickness, material choice, and fabrication method. Copolymer socket (CP) strengths depended on thickness and fabrication methods. A majority of the CSs and all of the CPs failed to pass the ISO 10328 ductile loading criterion. In contrast, the strengths of definitive laminated sockets (DLs) were influenced more by construction material and technique. A majority of the DLs failed to pass the ISO 10328 brittle loading criterion. Analyzing prosthetic sockets from a variety of facilities demonstrated that socket performance varies considerably between and within facilities. The results from this article provide a foundation for understanding the quality of prosthetic sockets, some insight into possible routes for improving the current care delivered to patients, and a comparative basis for future technology.
Wernke, Matthew M.; Schroeder, Ryan M.; Haynes, Michael L.; Nolt, Lonnie L.; Albury, Alexander W.; Colvin, James M.
2017-01-01
Objective: Prosthetic sockets are custom made for each amputee, yet there are no quantitative tools to determine the appropriateness of socket fit. Ensuring a proper socket fit can have significant effects on the health of residual limb soft tissues and overall function and acceptance of the prosthetic limb. Previous work found that elevated vacuum pressure data can detect movement between the residual limb and the prosthetic socket; however, the correlation between the two was specific to each user. The overall objective of this work is to determine the relationship between elevated vacuum pressure deviations and prosthetic socket fit. Approach: A tension compression machine was used to apply repeated controlled forces onto a residual limb model with sockets of different internal volume. Results: The vacuum pressure–displacement relationship was dependent on socket fit. The vacuum pressure data were sensitive enough to detect differences of 1.5% global volume and can likely detect differences even smaller. Limb motion was reduced as surface area of contact between the limb model and socket was maximized. Innovation: The results suggest that elevated vacuum pressure data provide information to quantify socket fit. Conclusions: This study provides evidence that the use of elevated vacuum pressure data may provide a method for prosthetists to quantify and monitor socket fit. Future studies should investigate the relationship between socket fit, limb motion, and limb health to define optimal socket fit parameters. PMID:28736683
NASA Astrophysics Data System (ADS)
Bonazzi, Enrico; Colombini, Elena; Panari, Davide; Vergnano, Alberto; Leali, Francesco; Veronesi, Paolo
2017-01-01
The integration of experiments with numerical simulations can efficiently support a quick evaluation of the welded joint. In this work, the MIG welding operation on aluminum T-joint thin plate has been studied by the integration of both simulation and experiments. The aim of the paper is to enlarge the global database, to promote the use of thin aluminum sheets in automotive body industries and to provide new data. Since the welding of aluminum thin plates is difficult to control due to high speed of the heat source and high heat flows during heating and cooling, a simulation model could be considered an effective design tool to predict the real phenomena. This integrated approach enables new evaluation possibilities on MIG-welded thin aluminum T-joints, as correspondence between the extension of the microstructural zones and the simulation parameters, material hardness, transient 3D temperature distribution on the surface and inside the material, stresses, strains, and deformations. The results of the mechanical simulations are comparable with the experimental measurements along the welding path, especially considering the variability of the process. The results could well predict the welding-induced distortion, which together with local heating during welding must be anticipated and subsequently minimized and counterbalance.
Substrateless Welding of Self-Assembled Silver Nanowires at Air/Water Interface.
Hu, Hang; Wang, Zhongyong; Ye, Qinxian; He, Jiaqing; Nie, Xiao; He, Gufeng; Song, Chengyi; Shang, Wen; Wu, Jianbo; Tao, Peng; Deng, Tao
2016-08-10
Integrating connected silver nanowire networks with flexible polymers has appeared as a popular way to prepare flexible electronics. To reduce the contact resistance and enhance the connectivity between silver nanowires, various welding techniques have been developed. Herein, rather than welding on solid supporting substrates, which often requires complicated transferring operations and also may pose damage to heat-sensitive substrates, we report an alternative approach to prepare easily transferrable conductive networks through welding of self-assembled silver nanowires at the air/water interface using plasmonic heating. The intriguing welding behavior of partially aligned silver nanowires was analyzed with combined experimental observation and theoretical modeling. The underlying water not only physically supports the assembled silver nanowires but also buffers potential overheating during the welding process, thereby enabling effective welding within a broad range of illumination power density and illumination duration. The welded networks could be directly integrated with PDMS substrates to prepare high-performance stable flexible heaters that are stretchable, bendable, and can be easily patterned to explore selective heating applications.
2016-10-01
satisfaction with device’’ (i.e. prosthesis) than the IC Socket. During year 1, we received all required IRB approvals, registered the clinical... satisfaction with device” (i.e. prosthesis) than the IC Socket. 2. KEYWORDS: Prosthetic Socket, Artificial Limbs, Prosthesis, Transfemoral Amputee, Gait...FlexSIV Socket will result in better quality of life and “ satisfaction with device” (i.e. prosthesis) than the IC socket. Accomplishments under
NASA Technical Reports Server (NTRS)
Rummel, W. D.; Rathke, R. A.; Todd, P. H., Jr.; Mullen, S. J.
1975-01-01
Liquid penetrant, ultrasonic, eddy current and X-radiographic techniques were optimized and applied to the evaluation of 2219-T87 aluminum alloy test specimens in integrally stiffened panel, and weld panel configurations. Fatigue cracks in integrally stiffened panels, lack-of-fusion in weld panels, and fatigue cracks in weld panels were the flaw types used for evaluation. A 2319 aluminum alloy weld filler rod was used for all welding to produce the test specimens. Forty seven integrally stiffened panels containing a total of 146 fatigue cracks, ninety three lack-of-penetration (LOP) specimens containing a total of 239 LOP flaws, and one-hundred seventeen welded specimens containing a total of 293 fatigue cracks were evaluated. Nondestructive test detection reliability enhancement was evaluated during separate inspection sequences in the specimens in the 'as-machined or as-welded', post etched and post proof loaded conditions. Results of the nondestructive test evaluations were compared to the actual flaw size obtained by measurement of the fracture specimens after completing all inspection sequences. Inspection data were then analyzed to provide a statistical basis for determining the flaw detection reliability.
Hachisuka, K; Matsushima, Y; Ohmine, S; Shitama, H; Shinkoda, K
2001-09-01
The purpose of this study was to examine the moisture permeability properties of materials used for total surface bearing (TSB) socket with a silicone liner, a combination of Silicone Suction Socket or Icelandic Roll-On Silicone Socket (ICEROSS) and an acrylic plastic sheet (Degaplast), patella-tendon bearing (PTB) socket, a combination of Pe-Lite and Degaplast, and wooden socket made of poplar. Moisture permeability of the socket materials was measured as the diminution of water in a container after 12 hours in a climatic chamber. Eight containers with their open, top side were uncovered (no material) or sealed with one of the socket materials; the experiment was repeated four times. One-way analysis of variance followed by Bonferroni's test was applied to examine the differences in moisture permeability. Moisture permeability levels were as follows: no material, 85.9 +/- 1.3 g; poplar, 4.3 +/- 0.4 g; Silicone Suction Socket, 1.1 +/- 0.2 g; ICEROSS, 1.0 +/- 0.2 g; Pe-Lite, 0.8 +/- 0.1 g; 3S + Degaplast, 0.8 +/- 0.1 g; ICEROSS + Degaplast, 0.8 +/- 0.2 g; and Pe-Lite + Degaplast, 0.8 +/- 0.1 g. There were significant differences between the uncovered container and the others, and between poplar and the others (P < 0.05). We concluded that the TSB socket with a silicone liner is not superior to the PTB socket with regard to moisture permeability, and that it is necessary to develop a new prosthetic socket that allows heat release and drainage of sweat.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pimputkar, S.M.; McCoy, J.K.; Stets, J.A.
1991-03-01
The integrity of a pipeline system is determined by its weakest links which may be the joints. Heat fusion is the most common method for joining gas distribution polyethylene (PE) piping. There are procedural, thermal, and mechanical aspects of making fusion joints. Acceptable procedural aspects, such as heater calibration and cleanliness, can be assured by rigorous training and certification of the operators. Thermal and mechanical aspects consist of specifying joining conditions such as the heater temperature, heating time, and joining pressure. In the absence of procedural errors, the strength of a fusion joint should depend on the pipe material, pipemore » dimensions, and the thermal and mechanical joining conditions. Socket heat fusion was studied both experimentally and analytically to determine how the strength of the joint varied with the conditions under which it was made. The standard tensile impact test was modified to test socket fusion joint samples in shear. The developed shear impact energy test data were found to be reliable measures of strength if the setups for conditions were meticulously identical. A parameter, termed the socket joining parameter, was found to characterize the joining conditions. It is a strong function of melt volume at the end of the heating phase, and physically, it is polyethylene transported parallel to the axis during insertion. The results for three resins are presented in the form of three nomographs. The nomographs may be used to select the required heater temperature or the heating time, for a given ambient temperature and a PE resin, to ensure a structurally sound socket heat fusion joint.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pimputkar, S.M.; McCoy, J.K.; Stets, J.A.
1991-03-01
The integrity of a pipeline system is determined by its weakest links which may be the joints. Heat fusion is the most common method for joining gas distribution polyethylene (PE) piping. There are procedural, thermal, and mechanical aspects of making fusion joints. Acceptable procedural aspects, such as heater calibration and cleanliness, can be assured by rigorous training and certification of the operators. Thermal and mechanical aspects consist of specifying joining conditions such as the heater temperature, heating time, and joining pressure. In the absence of procedural errors, the strength of a fusion joint should depend on the pipe material, pipemore » dimensions, and the thermal and mechanical joining conditions. Socket heat fusion was studied both experimentally and analytically to determine how the strength of the joint varied with the conditions under which it was made. The standard tensile impact test was modified to test socket fusion joint samples in shear. The developed shear impact energy test data were found to be reliable measures of strength if the setup conditions were meticulously identical. A parameter, termed the socket joining parameter, was found to characterize the joining conditions. It is a strong function of melt volume at the end of the heating phase, and, physically, it is polyethylene transported parallel to the axis during insertion. The results for three resins are presented in the form of three nomographs. The nomographs may be used to select the required heater temperature or the heating time, for a given ambient temperature and a PE resin, to ensure a structurally sound socket heat fusion joint.« less
Effect of alignment perturbations in a trans-tibial prosthesis user: A pilot study.
Courtney, Anna; Orendurff, Michael S; Buis, Arjan
2016-04-01
A recurring complication in trans-tibial prosthetic limb users is "poor socket fit" with painful residuum-socket interfaces, a consequence of excess pressure. This is due to both poor socket fit and poor socket alignment; however, the interaction of these factors has not been quantified. Through evaluation of kinetic data this study aimed to articulate an interaction uniting socket design, alignment and interface pressures. The results will help to refine future studies and will hopefully help determine whether sockets can be designed, fitted and aligned to maximize mobility whilst minimizing injurious forces. Interface pressures were recorded throughout ambulation in one user with "optimal (reference) alignment" followed by 5 malalignments in a patellar tendon-bearing and a hydrocast socket. Marked differences in pressure distribution were discovered when equating the patellar tendon-bearing against the hydrocast socket and when comparing interface pressures from reference with offset alignment. Patellar tendon-bearing sockets were found to be more sensitive to alignment perturbations than hydrocast sockets. A complex interaction was found, with the most prominent finding demonstrating the requisite for attainment of optimal alignment: a translational alignment error of 10 mm can increase maximum peak pressures by 227% (mean 17.5%). Refinements for future trials are described and the necessity for future research into socket design, alignment and interface pressures has been estabilished.
Araujo-Pires, Ana Claudia; Mendes, Vanessa Cristina; Ferreira-Junior, Osny; Carvalho, Paulo Sérgio Perri; Guan, Limin; Davies, John Edward
2016-06-01
It is expected that 40% to 60% of initial alveolar bone volume will be lost up to 6 months after tooth extraction. OsteoScaf(TM) (TRT, Toronto, ON, Canada) (poly (DL-lactide-co-glycololide/calcium phosphate [PLGA/CaP] scaffold) is a novel bone substitute material and represents a promising alternative for maintaining alveolar bone integrity in this clinical scenario. Here it was hypothesized that OsteoScaf would reduce alveolar bone lost after tooth extraction in patient, acting as a clot-retention device. A total of 10 patients (32 sockets) were included in the study, of which 16 sockets were grafted with OsteoScaf and 16 were used as control (coagulum alone). Cone beam computed tomography (CBCT) was performed both immediately following extraction and also at 120 days postoperatively, at which time biopsy samples were also harvested for histological analyses. Quantitative analysis of CBCT showed less bone resorption in the OsteoScaf groups, being 10.5% to 14.4% less bone lost in the center of the socket, 15.4% in the buccal region, and 12.6% in the palatal. Qualitative histological analysis showed new bone tissue in direct apposition to the scaffold - demonstrating its osteoconductive nature. OsteoScaf diminished the expected bone lost during the postextraction remodeling of the alveolar bone ridge at 120 days postextraction. © 2015 Wiley Periodicals, Inc.
Alveolar osteitis; Alveolitis; Septic socket ... You may be more at risk for dry socket if you: Have poor oral health Have a ... after having a tooth pulled Have had dry socket in the past Drink from a straw after ...
Healing of ungrafted and grafted extraction sockets after 12 weeks: a prospective clinical study.
Heberer, Susanne; Al-Chawaf, Bassem; Jablonski, Carlo; Nelson, John J; Lage, Hermann; Nelson, Katje
2011-01-01
In this prospective study, bone formation in human extraction sockets augmented with Bio-Oss Collagen after a 12-week healing period was quantified and compared to bone formation in unaugmented extraction sockets. Selected patients with four-walled extraction sockets were included in this prospective study. After extraction, the sockets were randomly augmented using Bio-Oss Collagen or left to heal unfilled without raising a mucoperiosteal flap. At the time of implant placement, histologic specimens were obtained from the socket and analyzed. Statistical analysis was performed using the Wilcoxon signed-rank test. Twenty-five patients with a total of 39 sockets (20 augmented, 19 unaugmented) were included in the study and the histologic specimens analyzed. All specimens were free of inflammatory cells. The mean overall new bone formation in the augmented sites was 25% (range, 8%-41%) and in the unaugmented sockets it was 44% (range, 3%-79%). There was a significant difference in the rate of new bone formation between the grafted and ungrafted sockets and a significant difference in the bone formation rate in the apical compared to the coronal regions of all sockets, independent of the healing mode. This descriptive study demonstrated that bone formation in Bio-Oss Collagen-grafted human extraction sockets was lower than bone formation in ungrafted sockets. Bone formation occurred in all specimens with varying degrees of maturation independent of the grafting material and was initiated from the apical region.
Al-Fakih, Ebrahim A; Abu Osman, Noor Azuan; Mahmad Adikan, Faisal Rafiq
2016-07-20
The distribution of interface stresses between the residual limb and prosthetic socket of a transtibial amputee has been considered as a direct indicator of the socket quality fit and comfort. Therefore, researchers have been very interested in quantifying these interface stresses in order to evaluate the extent of any potential damage caused by the socket to the residual limb tissues. During the past 50 years a variety of measurement techniques have been employed in an effort to identify sites of excessive stresses which may lead to skin breakdown, compare stress distributions in various socket designs, and evaluate interface cushioning and suspension systems, among others. The outcomes of such measurement techniques have contributed to improving the design and fitting of transtibial sockets. This article aims to review the operating principles, advantages, and disadvantages of conventional and emerging techniques used for interface stress measurements inside transtibial sockets. It also reviews and discusses the evolution of different socket concepts and interface stress investigations conducted in the past five decades, providing valuable insights into the latest trends in socket designs and the crucial considerations for effective stress measurement tools that lead to a functional prosthetic socket.
Al-Fakih, Ebrahim A.; Abu Osman, Noor Azuan; Mahmad Adikan, Faisal Rafiq
2016-01-01
The distribution of interface stresses between the residual limb and prosthetic socket of a transtibial amputee has been considered as a direct indicator of the socket quality fit and comfort. Therefore, researchers have been very interested in quantifying these interface stresses in order to evaluate the extent of any potential damage caused by the socket to the residual limb tissues. During the past 50 years a variety of measurement techniques have been employed in an effort to identify sites of excessive stresses which may lead to skin breakdown, compare stress distributions in various socket designs, and evaluate interface cushioning and suspension systems, among others. The outcomes of such measurement techniques have contributed to improving the design and fitting of transtibial sockets. This article aims to review the operating principles, advantages, and disadvantages of conventional and emerging techniques used for interface stress measurements inside transtibial sockets. It also reviews and discusses the evolution of different socket concepts and interface stress investigations conducted in the past five decades, providing valuable insights into the latest trends in socket designs and the crucial considerations for effective stress measurement tools that lead to a functional prosthetic socket. PMID:27447646
Shielded Metal Arc Welding. Welding Module 4. Instructor's Guide.
ERIC Educational Resources Information Center
Missouri Univ., Columbia. Instructional Materials Lab.
This guide is intended to assist vocational educators in teaching an eight-unit module in shielded metal arc welding. The module is part of a welding curriculum that has been designed to be totally integrated with Missouri's Vocational Instruction Management System. The following topics are covered in the module: safety; theory, power sources, and…
Gas Tungsten Arc Welding. Welding Module 6. Instructor's Guide.
ERIC Educational Resources Information Center
Missouri Univ., Columbia. Instructional Materials Lab.
This guide is intended to assist vocational educators in teaching a three-unit module in gas tungsten arc welding. The module has been designed to be totally integrated with Missouri's Vocational Instruction Management System. The basic principles involved in gas tungsten arc welding, supplies, and applications are covered. The materials included…
Mohd Hawari, Nurhanisah; Jawaid, Mohammad; Md Tahir, Paridah; Azmeer, Raja Ahmad
2017-11-01
The aim of this case study was to explore patient satisfaction with the quality of prosthetic leg sockets intended for persons with lower limb amputations. A qualitative study based on in-depth interviews, preceded by a questionnaire session, was carried out with patients from the Rehabilitation Center and Hospital in Malaysia. Twelve out-patient and in-patient amputees with lower limb amputations, specifically below-knee amputations, were chosen randomly. The analysis of patients' narratives aimed to identify the functional and esthetic characteristics of currently used prosthetic leg sockets and any problems related to them. The obtained results indicated that out of the 12 participants, 41.7% and 25% were satisfied and somewhat satisfied with their current prosthetic sockets. Durability and comfort were rated by the participants as the most important characteristics of prosthetic sockets, with 83.3%. As regards the esthetic appearance of the socket, 66.7% of the respondents considered that the most important feature was the material from which the socket was fabricated. Thus, we conclude that current satisfaction levels with the quality of prosthetic sockets among amputees in Malaysia are suitable, prosthesis being preferred by many amputees. The results can be used to direct future research on cosmesis and functionality of prosthetic socket design. Implications for Rehabilitation Case study will help participants to get cost effective prosthetic leg socket. Develop prosthetic leg socket comfortable as comparative to existing one. Help Malaysian government to make policy to develop local prosthetic leg socket at affordable price.
Robotic Variable Polarity Plasma Arc (VPPA) Welding
NASA Technical Reports Server (NTRS)
Jaffery, Waris S.
1993-01-01
The need for automated plasma welding was identified in the early stages of the Space Station Freedom Program (SSFP) because it requires approximately 1.3 miles of welding for assembly. As a result of the Variable Polarity Plasma Arc Welding (VPPAW) process's ability to make virtually defect-free welds in aluminum, it was chosen to fulfill the welding needs. Space Station Freedom will be constructed of 2219 aluminum utilizing the computer controlled VPPAW process. The 'Node Radial Docking Port', with it's saddle shaped weld path, has a constantly changing surface angle over 360 deg of the 282 inch weld. The automated robotic VPPAW process requires eight-axes of motion (six-axes of robot and two-axes of positioner movement). The robot control system is programmed to maintain Torch Center Point (TCP) orientation perpendicular to the part while the part positioner is tilted and rotated to maintain the vertical up orientation as required by the VPPAW process. The combined speed of the robot and the positioner are integrated to maintain a constant speed between the part and the torch. A laser-based vision sensor system has also been integrated to track the seam and map the surface of the profile during welding.
Robotic Variable Polarity Plasma Arc (VPPA) welding
NASA Astrophysics Data System (ADS)
Jaffery, Waris S.
1993-02-01
The need for automated plasma welding was identified in the early stages of the Space Station Freedom Program (SSFP) because it requires approximately 1.3 miles of welding for assembly. As a result of the Variable Polarity Plasma Arc Welding (VPPAW) process's ability to make virtually defect-free welds in aluminum, it was chosen to fulfill the welding needs. Space Station Freedom will be constructed of 2219 aluminum utilizing the computer controlled VPPAW process. The 'Node Radial Docking Port', with it's saddle shaped weld path, has a constantly changing surface angle over 360 deg of the 282 inch weld. The automated robotic VPPAW process requires eight-axes of motion (six-axes of robot and two-axes of positioner movement). The robot control system is programmed to maintain Torch Center Point (TCP) orientation perpendicular to the part while the part positioner is tilted and rotated to maintain the vertical up orientation as required by the VPPAW process. The combined speed of the robot and the positioner are integrated to maintain a constant speed between the part and the torch. A laser-based vision sensor system has also been integrated to track the seam and map the surface of the profile during welding.
Advances in welding science: A perspective
NASA Astrophysics Data System (ADS)
David, S. A.; Vitek, J. M.; Babu, S. S.; Debroy, T.
The ultimate goal of welding technology is to improve the joint integrity and increase productivity. Over the years, welding has been more of an art than a science, but in the last few decades major advances have taken place in welding science and technology. With the development of new methodologies at the crossroads of basic and applied sciences, enormous opportunities and potential exist to develop a science-based tailoring of composition, structure, and properties of welds with intelligent control and automation of the welding processes.
TAKETOMI, SHUJI; INUI, HIROSHI; NAKAMURA, KENSUKE; YAMAGAMI, RYOTA; TAHARA, KEITARO; SANADA, TAKAKI; MASUDA, HIRONARI; TANAKA, SAKAE; NAKAGAWA, TAKUMI
2015-01-01
Purpose the efficacy and safety of using a suspensory button for femoral fixation in anatomical anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone (BPTB) graft have not been established. The purpose of the current study was to evaluate bone plug integration onto the femoral socket and migration of the bone plug and the EndoButton (EB) (Smith & Nephew, Andover, MA, USA) after rectangular tunnel ACL reconstruction with BPTB autograft. Methods thirty-four patients who underwent anatomical rectangular ACL reconstruction with BPTB graft using EB for femoral fixation and in whom three-dimensional (3D) computed tomography (CT) was performed one week and one year after surgery were included in this study. Bone plug integration onto the femoral socket, bone plug migration, soft tissue interposition, EB migration and EB rotation were evaluated on 3D CT. The clinical outcome was also assessed and correlated with the imaging outcomes. Results the bone plug was integrated onto the femoral socket in all cases. The incidence of bone plug migration, soft tissue interposition, EB migration and EB rotation was 15, 15, 9 and 56%, respectively. No significant association was observed between the imaging outcomes. The postoperative mean Lysholm score was 97.1 ± 5.0 points. The postoperative side-to-side difference, evaluated using a KT-2000 arthrometer, averaged 0.5 ± 1.3 mm. There were no complications associated with EB use. Imaging outcomes did not affect the postoperative KT side-to-side difference. Conclusions the EB is considered a reliable device for femoral fixation in anatomical rectangular tunnel ACL reconstruction with BPTB autograft. Level of evidence Level IV, therapeutic case series. PMID:26889465
Kahle, Jason T.; Klenow, Tyler D.; Highsmith, M. Jason
2016-01-01
The socket-limb interface is vital for functionality and provides stability and mobility for the amputee. Volume fluctuation can lead to compromised fit and function. Current socket technology does not accommodate for volume fluctuation. An adjustable interface may improve function and comfort by filling this technology gap. The purpose of this study was to compare the effectiveness of the standard of care (SOC) ischial ramus containment to an adjustable transfemoral prosthetic interface socket in the accommodation of volume fluctuation. A prospective experimental case study using repeated measures of subjective and performance outcome measures between socket conditions was employed. In the baseline volume condition, the adjustable socket improved subjective and performance measures 19% to 37% over SOC, whereas the two-minute walk test demonstrated equivalence. In the volume loss condition, the adjustable socket improved all subjective and performance measures 22% to 93%. All aggregated data improved 16% to 50% compared with the SOC. In simulated volume gain, the SOC socket failed, while the subject was able to complete the protocol using the adjustable socket. In this case study, the SOC socket was inferior to the comparative adjustable transfemoral amputation interface in subjective and performance outcomes. There is a lack of clinical trials and evidence comparing socket functional outcomes related to volume fluctuation. PMID:28066526
Komatsu, Teruya; Sakaguchi, Yasuto; Muranishi, Yusuke; Yutaka, Yojiro; Date, Hiroshi; Nakamura, Tatsuo
2018-01-01
Background Costal coaptation pins made of poly-L-lactide (PLA) are clinically available for fixing surgically divided ribs. However, the clinical results of such rib fixation have not been completely satisfactory. We aimed to develop a new rib coaptation socket system and explore its clinical applicability. Methods We surgically divided three consecutive ribs of each beagle dog, and rib coaptation sockets were implanted to stabilize each rib. Fifteen 3-dimensional (3D)-printed and 30 PLA fiber knitted sockets were implanted in five and ten dogs, respectively, to stabilize the artificially divided ribs. Mechanical analysis of the sockets and radiographical examination of costal fixation were performed to evaluate the effectiveness of the newly developed socket system for rib stabilization. Results All 15 ribs with 3D-printed sockets had displaced 1 month after the operation. Three ribs in one dog with implanted PLA fiber knitted sockets were displaced radiographically after 1 month, and the grade of displacement remained unchanged after 6 months. The remaining 27 ribs fixed with PLA fiber knitted sockets did not show any displacement. Conclusions The PLA fiber knitted rib coaptation socket system was sufficiently durable for the stabilization of divided ribs with biocompatibility. This promising finding can be applied for clinical stabilization of divided ribs. PMID:29850125
Laing, Sheridan; Lythgo, Noel; Lavranos, Jim; Lee, Peter Vee Sin
2017-10-01
This study compared the physical function and comfort level of patients with unilateral transtibial amputation after being fitted with a hand-cast Patella Tendon Bearing (PTB) socket and a pressure-cast (PCAST) hydrocast socket. The latter technique aims to reduce the skill dependency currently required for socket manufacture and fit. The study was conducted at the Vietnamese Training Centre for Orthopaedic Technologies and involved seventeen Vietnamese participants with unilateral transtibial amputation, all of whom were long term users of prosthetics. All participants were fitted with two sockets manufactured using both hand-cast and PCAST techniques with International Committee of the Red Cross components. Walking tests (timed up and go test and six-minute-walk-test), spatio-temporal gait analyses and subjective comfort assessments were completed after a short acclimatisation period with each socket. The participant-preferred socket was also noted. No significant differences were found for the measures of mobility, functional capacity, spatio-temporal gait parameters, gait symmetry, perceived comfort or participant socket preference. The results show the initial patient outcomes are similar when participants are fitted with a hand-cast PTB socket and a PCAST hydrocast sockets. Future work should confirm these findings in a longer trial. Copyright © 2017 Elsevier B.V. All rights reserved.
Komatsu, Teruya; Sato, Toshihiko; Sakaguchi, Yasuto; Muranishi, Yusuke; Yutaka, Yojiro; Date, Hiroshi; Nakamura, Tatsuo
2018-04-01
Costal coaptation pins made of poly-L-lactide (PLA) are clinically available for fixing surgically divided ribs. However, the clinical results of such rib fixation have not been completely satisfactory. We aimed to develop a new rib coaptation socket system and explore its clinical applicability. We surgically divided three consecutive ribs of each beagle dog, and rib coaptation sockets were implanted to stabilize each rib. Fifteen 3-dimensional (3D)-printed and 30 PLA fiber knitted sockets were implanted in five and ten dogs, respectively, to stabilize the artificially divided ribs. Mechanical analysis of the sockets and radiographical examination of costal fixation were performed to evaluate the effectiveness of the newly developed socket system for rib stabilization. All 15 ribs with 3D-printed sockets had displaced 1 month after the operation. Three ribs in one dog with implanted PLA fiber knitted sockets were displaced radiographically after 1 month, and the grade of displacement remained unchanged after 6 months. The remaining 27 ribs fixed with PLA fiber knitted sockets did not show any displacement. The PLA fiber knitted rib coaptation socket system was sufficiently durable for the stabilization of divided ribs with biocompatibility. This promising finding can be applied for clinical stabilization of divided ribs.
Flügge, Tabea; Nelson, Katja; Nack, Claudia; Stricker, Andres; Nahles, Susanne
2015-04-01
This study identified the soft tissue changes of the alveolar ridge at different time points within 12 weeks after tooth extraction with and without socket augmentation. In 38 patients with single tooth extractions, 40 sockets were augmented and 39 extraction sockets were not augmented. At 2, 4, 6, 8 and 12 weeks impressions were taken and casts digitized with a laser scanner. The horizontal and vertical changes were compared between augmented and non-augmented sites. A p-value <0.05 was considered statistically significant. The mean changes of augmented sockets were between 0.4 mm (2 weeks) and 0.8 mm (12 weeks). In non-augmented sockets changes of 0.7 mm (2 weeks) and of 1.0 mm (12 weeks) were demonstrated. The mean values differed significantly between the buccal and oral region (p < 0.01). Overall, there were significant differences of the mean dimensional changes regarding time (p < 0.01) and augmentation (p < 0.01). Augmented sockets showed less resorption within 4 weeks after extraction compared to non-augmented sockets. Non-augmented sockets showed a continuous dimensional loss with a great variation over 12 weeks whereas augmented sockets had the highest degree of resorption between 4 and 6 weeks. At 12 weeks a comparable resorption in augmented and non-augmented sockets was observed. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Continuity tester screens out faulty socket connections
NASA Technical Reports Server (NTRS)
Golding, G.
1964-01-01
A device, used before and after assembly, tests the continuity of an electrical circuit through each pin and socket of multiple connector sockets. Electrically insulated except at the contact area, a test probe is dimensioned to make contact only in properly formed sockets.
Darter, Benjamin J; Sinitski, Kirill; Wilken, Jason M
2016-10-01
Elevated vacuum suspension systems use a pump to draw air from the socket with the intent of reducing bone-socket motion as compared to passive suction systems. However, it remains unknown if elevated vacuum suspension systems decrease limb displacement uniformly during transitions from unloaded to full-body-weight support. To compare limb-socket motion between elevated vacuum and passive suction suspension sockets using a controlled loading paradigm. Comparative analysis. Persons with transtibial amputation were assessed while wearing either an elevated vacuum or passive suction suspension socket. Digital video fluoroscopy was used to measure axial bone-socket motion while the limb was loaded in 20% body-weight increments. An analysis of variance model was used to compare between suspension types. Total axial displacement (0%-100% body weight) was significantly lower using the elevated vacuum (vacuum: 1.3 cm, passive suction: 1.8 cm; p < 0.0001). Total displacement decreased primarily due to decreased motion during initial loading (0%-20%; p < 0.0001). Other body-weight intervals were not significantly different between systems. Elevated vacuum suspension reduced axial limb-socket motion by maintaining position of the limb within the socket during unloaded conditions. Elevated vacuum provided no meaningful improvement in limb-socket motion past initial loading. Excessive bone-socket motion contributes to poor residual limb health. Our results suggest elevated vacuum suspensions can reduce this axial displacement. Visual assessment of the images suggests that this occurs through the reduction or elimination of the air pocket between the liner and socket wall while the limb is unloaded. © The International Society for Prosthetics and Orthotics 2015.
Gas Metal Arc Welding. Welding Module 5. Instructor's Guide.
ERIC Educational Resources Information Center
Missouri Univ., Columbia. Instructional Materials Lab.
This guide is intended to assist vocational educators in teaching an eight-unit module in gas metal arc welding. The module is part of a welding curriculum that has been designed to be totally integrated with Missouri's Vocational Instruction Management System. The following topics are covered in the module: safety and testing, gas metal arc…
A retrospective study on the use of a dental dressing to reduce dry socket incidence in smokers.
Murph, James T; Jaques, Susan H; Knoell, Alexander N; Archibald, Geoffrey D; Yang, Stan
2015-01-01
This study assessed the effectiveness of using an oxidized cellulose dental dressing in order to reduce the rate of alveolar osteitis after posterior tooth extraction in smokers. Dry socket incidences of heavy smokers from 4 independent dental clinics, which routinely used oxidized cellulose dental dressings to mitigate dry socket formation between March 2011 and December 2012, were compiled and evaluated. All extraction sites healed uneventfully except for those cases that developed dry sockets. Overall, 1.7% of male patients and 2.2% of female patients developed dry sockets. No conclusive relationship was found between the number of cigarettes smoked and dry socket formation among patients in this study. The results of this study were consistent with the view that gender, age, postextraction regimen, and multiple extractions affect dry socket formation. The results indicate that an oxidized cellulose dental dressing postextraction is a safe and effective method for mitigating dry socket formation among smokers.
Dry socket: incidence, clinical features, and predisposing factors.
Akinbami, Babatunde O; Godspower, Thikan
2014-01-01
Background. Dry socket is a global phenomenon. The purpose of the study was to investigate the incidence of dry socket in recent times in a Nigerian Tertiary Hospital. Methods. Patients who were referred for dental extractions were included in the study. The case files of patients were obtained and information retrieved included biodata, indication for extraction, number and type of teeth extracted, oral hygiene status, compliance to oral hygiene instructions, and development of dry socket. Results. One thousand, one hundred and eighty two patients with total of 1362 teeth extracted during the 4-year period of the study were analyzed, out of which 1.4% teeth developed dry socket. The mean age (SD) was 35.2 (16.0) years. Most of the patients who presented with dry socket were in the fourth decade of life. Mandibular teeth were affected more than maxillary teeth. Molars were more affected. Retained roots and third molars were conspicuous in the cases with dry socket. Conclusion. The incidence of dry socket in our centre was lower than previous reports. Oral hygiene status, lower teeth, and female gender were significantly associated with development of dry socket. Treatment with normal saline irrigation and ZnO eugenol dressings allowed relief of the symptoms.
Dry Socket: Incidence, Clinical Features, and Predisposing Factors
Akinbami, Babatunde O.; Godspower, Thikan
2014-01-01
Background. Dry socket is a global phenomenon. The purpose of the study was to investigate the incidence of dry socket in recent times in a Nigerian Tertiary Hospital. Methods. Patients who were referred for dental extractions were included in the study. The case files of patients were obtained and information retrieved included biodata, indication for extraction, number and type of teeth extracted, oral hygiene status, compliance to oral hygiene instructions, and development of dry socket. Results. One thousand, one hundred and eighty two patients with total of 1362 teeth extracted during the 4-year period of the study were analyzed, out of which 1.4% teeth developed dry socket. The mean age (SD) was 35.2 (16.0) years. Most of the patients who presented with dry socket were in the fourth decade of life. Mandibular teeth were affected more than maxillary teeth. Molars were more affected. Retained roots and third molars were conspicuous in the cases with dry socket. Conclusion. The incidence of dry socket in our centre was lower than previous reports. Oral hygiene status, lower teeth, and female gender were significantly associated with development of dry socket. Treatment with normal saline irrigation and ZnO eugenol dressings allowed relief of the symptoms. PMID:24987419
Mitton, Kay; Kulkarni, Jai; Dunn, Kenneth William; Ung, Anthony Hoang
2017-10-01
This novel case report describes the problems of prescribing a prosthetic socket in a left transfemoral amputee secondary to chronic patellofemoral instability compounded by complex regional pain syndrome. Case Description and Methods: Following the amputation, complex regional pain syndrome symptoms recurred in the residual limb, presenting mainly with oedema. Due to extreme daily volume fluctuations of the residual limb, a conventional, laminated thermoplastic socket fitting was not feasible. Findings and Outcomes: An adjustable, modular socket design was trialled. The residual limb volume fluctuations were accommodated within the socket. Amputee rehabilitation could be continued, and the rehabilitation goals were achieved. The patient was able to wear the prosthesis for 8 h daily and to walk unaided indoors and outdoors. An adjustable, modular socket design accommodated the daily residual limb volume fluctuations and provided a successful outcome in this case. It demonstrates the complexities of socket fitting and design with volume fluctuations. Clinical relevance Ongoing complex regional pain syndrome symptoms within the residual limb can lead to fitting difficulties in a conventional, laminated thermoplastic socket due to volume fluctuations. An adjustable, modular socket design can accommodate this and provide a successful outcome.
Wang, Yao-zhong; Guan, Qun-li; Li, Ya-xin; Guo, Ji-lai; Jiang, Ling; Jia, Mu-yun; Deng, Yue
2013-02-01
To study the clinical effect of "gelatamp" colloidal silver gelatin sponge on preventing dry socket after extracting the mandibular impacted teeth. 1350 teeth extracted from 976 patients who needed to extract the mandibular impacted teeth were divided into group A, group B and group C randomly. "Gelatamp" colloidal silver gelatin sponge was implanted into alveolar socket after teeth extraction in group A, with absorbable gelatin sponge was implanted into alveolar socket in group B and nothing was implanted into alveolar socket in group C. The incidence of dry socket was observed, the data was analyzed using SPSS10.0 software package. The incidence of dry socket was 0.44% in group A, 2% in group B and 4.44% in group C. There was significant difference in the incidence of dry socket between group A and group C(P<0.01). There was also significant difference between group B and group C(P<0.05) and between group A and group B(P<0.05). The results demonstrate that "gelatamp" colloidal silver gelatin sponge can prevent the occurrence of dry socket after teeth extraction, which is of wide clinical use.
Interventions for the prevention of dry socket: an evidence-based update.
Sharif, M O; Dawoud, B E S; Tsichlaki, A; Yates, J M
2014-07-11
This paper reviews the latest evidence for local and systemic interventions for the prevention of alveolar osteitis (dry socket). Dry socket is a painful and common post-operative complication following exodontia. Any interventions for the prevention of dry socket could reduce both its incidence and help avoid this painful complication. Prophylactic measures proposed in the literature are discussed. Furthermore, this article discusses both the clinical and histological stages of a normal healing socket.
Coronal plane socket stability during gait in persons with transfemoral amputation: Pilot study.
Fatone, Stefania; Dillon, Michael; Stine, Rebecca; Tillges, Robert
2014-01-01
Little research describes which transfemoral socket design features are important for coronal plane stability, socket comfort, and gait. Our study objectives were to (1) relate socket comfort during gait to a rank order of changes in ischial containment (IC) and tissue loading and (2) compare socket comfort during gait when tissue loading and IC were systematically manipulated. Six randomly assigned socket conditions (IC and tissue compression) were assessed: (1) IC and high, (2) IC and medium, (3) IC and low, (4) no IC and high, (5) no IC and medium, and (6) no IC and low. For the six subjects in this study, there was a strong, negative relationship between comfort and changes in IC and tissue loading (rho = -0.89). With the ischium contained, tissue loading did not influence socket comfort (p = 0.47). With no IC, the socket was equally comfortable with high tissue loading (p = 0.36) but the medium (p = 0.04) and low (p = 0.02) tissue loading conditions decreased comfort significantly. Coronal plane hip moments, lateral trunk lean, step width, and walking speed were invariant to changes in IC and/or tissue loading. Our results suggest that in an IC socket, medial tissue loading mattered little in terms of comfort. Sockets without IC required high tissue loading to be as comfortable as those with IC, while suboptimal tissue loading compromised comfort.
Single-Rooted Extraction Sockets: Classification and Treatment Protocol.
El Chaar, Edgar; Oshman, Sarah; Fallah Abed, Pooria
2016-09-01
Clinicians have many treatment techniques from which to choose when extracting a failing tooth and replacing it with an implant-supported restoration and when successful management of an extraction socket during the course of tooth replacement is necessary to achieve predictable and esthetic outcomes. This article presents a straightforward, yet thorough, classification for extraction sockets of single-rooted teeth and provides guidance to clinicians in the selection of appropriate and predictable treatment. The presented classification of extraction sockets for single-rooted teeth focuses on the topography of the extraction socket, while the protocol for treatment of each socket type factors in the shape of the remaining bone, the biotype, and the location of the socket whether it be in the mandible or maxilla. This system is based on the biologic foundations of wound healing and can help guide clinicians to successful treatment outcomes.
Modular socket system versus traditionally laminated socket: a cost analysis.
Normann, Elna; Olsson, Anna; Brodtkorb, Thor-Henrik
2011-03-01
Using the new modular socket system (MSS) to produce a prosthetic socket directly on the patient has the potential of being easier and quicker to manufacture but also incurring higher costs. The purpose of the study was to compare the costs of manufacturing a transtibial prosthetic socket using either a MSS or a standard laminated socket (PC). Concurrent controlled trial. A total of 20 patients at two orthopaedic facilities were followed with regards to the cost of manufacturing a prosthetic socket using either MSS or PC. Time aspects and material costs were considered in the cost analysis. Other factors studied include delivery time and number of visits. For the cost analysis, only direct costs pertaining to the prosthetic socket were considered. The total cost of MSS was found to be significantly higher (p < 0.01) compared to PC. However, the production and time cost was significantly lower. Delivery time to the patient was 1 day for MSS compared to 17 days for PC. Our study shows that the direct prosthetic cost of treating a patient using MSS is significantly higher than treating a patient using PC. However, the MSS prosthesis can be delivered significantly faster and with fewer visits. Further studies taking the full societal costs of MSS into account should therefore be performed. This study shows that the direct prosthetic cost of treating a patient with Modular Socket System is significantly higher than treating a patient with plastercasting with standard laminated socket. However, the Modular Socket System prosthesis can be delivered significantly faster and with fewer visits.
An Amino Acid Code for Irregular and Mixed Protein Packing
Joo, Hyun; Chavan, Archana; Fraga, Keith; Tsai, Jerry
2015-01-01
To advance our understanding of protein tertiary structure, the development of the knob-socket model is completed in an analysis of the packing in irregular coil and turn secondary structure packing as well as between mixed secondary structure. The knob-socket model simplifies packing based on repeated patterns of 2 motifs: a 3 residue socket for packing within 2° structure and a 4 residue knob-socket for 3° packing. For coil and turn secondary structure, knob-sockets allow identification of a correlation between amino acid composition and tertiary arrangements in space. Coil contributes almost as much as α-helices to tertiary packing. Irregular secondary structure involves 3 residue cliques of consecutive contacting residues or XYZ sockets. In irregular sockets, Gly, Pro, Asp and Ser are favored, while Cys, His, Met and Trp are not. For irregular knobs, the preference order is Arg, Asp, Pro, Asn, Thr, Leu, and Gly, while Cys, His, Met and Trp are not. In mixed packing, the knob amino acid preferences are a function of the socket that they are packing into, whereas the amino acid composition of the sockets does not depend on the secondary structure of the knob. A unique motif of a coil knob with an XYZ β-sheet socket may potentially function to inhibit β-sheet extension. In addition, analysis of the preferred crossing angles for strands within a β-sheet and mixed α-helices/β-sheets identifies canonical packing patterns useful in protein design. Lastly, the knob-socket model abstracts the complexity of protein tertiary structure into an intuitive packing surface topology map. PMID:26370334
Sodium hyaluronate accelerates the healing process in tooth sockets of rats.
Mendes, Renato M; Silva, Gerluza A B; Lima, Miguel F; Calliari, Marcelo V; Almeida, Alvair P; Alves, José B; Ferreira, Anderson J
2008-12-01
In this study we evaluated the effects of sodium hyaluronate (HY) in the healing process of tooth sockets of rats. Immediately after the extraction of the upper first molars of male Holtzman rats, right sockets were treated with 1% HY gel (approximately 0.1 ml), while left sockets were used as control (blood clot). The animals were sacrificed at 2, 7, and 21 days after tooth extraction and upper maxillaries processed for histological and morphometric analysis of the apical and medium thirds of the sockets. Carbopol, an inert gel, was used to evaluate the mechanical effect of gel injection into sockets. Expression of bone morphogenetic protein-2 (BMP-2) and osteopontin (OPN) was determined by immunohistochemistry at 1, 2, 3, 4, 5, and 7 days after tooth extraction. Histological analysis showed that HY treatment induced earlier trabecular bone deposition resulting in a bone matrix more organized at 7 and 21 days after tooth extraction. Also, HY elicited significant increase in the amount of bone trabeculaes at 7 and 21 days after tooth extraction (percentage of trabecular bone area at 7 days: 13.21+/-4.66% vs. 2.58+/-1.36% in the apical third of control sockets) and in the vessels counting at 7 days. Conversely, the number of cell nuclei was decreased in HY-treated sockets. Additionally, expression of BMP-2 and OPN was enhanced in HY-treated sockets compared with control sockets. These findings suggest that HY accelerates the healing process in tooth sockets of rats stimulating the expression of osteogenic proteins.
Dry Socket: Frequency, Clinical Picture, and Risk Factors in a Palestinian Dental Teaching Center
Abu Younis, Mohammed H; Abu Hantash, Ra'ed O
2011-01-01
Aims: The objectives of this study were to find out the frequency, clinical picture, and risk factors of dry socket at the Dental Teaching Center of Al-Quds University in Palestine. Methods and Materials: Two previously used questionnaires were accomplished in this study over a one year period. The first questionnaire was completed for every patient who had one or more permanent teeth extracted in the Dental Surgery Clinic. The other one was completed for every patient suffered a postoperative pain and was diagnosed with dry socket. Results: There were 1305 dental extractions performed in 805 patients. The overall frequency of dry socket was 3.2%. The incidence of dry socket following non-surgical extractions was 1.7% while it was 15% following surgical extractions (P< 0.005). The incidence of dry socket was significantly higher in smokers (12%) than in non-smokers (4%) (P < 0.005), however, there is a strong association between the amount of smoking and the incidence of dry socket (P < 0.002). The incidence of dry socket was significantly higher in the single extraction cases (13%) than in the multiple extraction cases (5%) (P = 0.005). Age, sex, medical history, extraction site, amount of local anesthesia and experience of operator play no role in the occurrence of dry socket. Conclusion: Smoking, surgical trauma and single extractions are considered predisposing factors in the occurrence of dry socket. On the other hand, factors like: age, sex, medical history, extraction site, amount of anesthesia, and operator experience have no effect on the observation of dry socket. PMID:21559187
30 CFR 57.12035 - Weatherproof lamp sockets.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Weatherproof lamp sockets. 57.12035 Section 57.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12035 Weatherproof lamp sockets. Lamp sockets shall be of a weatherproof type...
30 CFR 57.12035 - Weatherproof lamp sockets.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Weatherproof lamp sockets. 57.12035 Section 57.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12035 Weatherproof lamp sockets. Lamp sockets shall be of a weatherproof type...
30 CFR 57.12035 - Weatherproof lamp sockets.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Weatherproof lamp sockets. 57.12035 Section 57.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12035 Weatherproof lamp sockets. Lamp sockets shall be of a weatherproof type...
30 CFR 57.12035 - Weatherproof lamp sockets.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Weatherproof lamp sockets. 57.12035 Section 57.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12035 Weatherproof lamp sockets. Lamp sockets shall be of a weatherproof type...
30 CFR 57.12035 - Weatherproof lamp sockets.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Weatherproof lamp sockets. 57.12035 Section 57.12035 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12035 Weatherproof lamp sockets. Lamp sockets shall be of a weatherproof type...
NASA Technical Reports Server (NTRS)
Wang, Peter Hor-Ching
1996-01-01
This study is a continuation of the summer research of 1995 NASA/ASEE Summer Faculty Fellowship Program. This effort is to provide the infrastructure of an integrated Virtual Reality (VR) environment for the International Space Welding Experiment (ISWE) Analytical Tool and Trainer and the Microgravity Science Glovebox (MSG) Analytical Tool study. Due to the unavailability of the MSG CAD files and the 3D-CAD converter, little was done to the MSG study. However, the infrastructure of the integrated VR environment for ISWE is capable of performing the MSG study when the CAD files become available. Two primary goals are established for this research. First, the essential peripheral devices for an integrated VR environment will be studied and developed for the ISWE and MSG studies. Secondly, the training of the flight crew (astronaut) in general orientation, procedures, and location, orientation, and sequencing of the welding samples and tools are built into the VR system for studying the welding process and training the astronaut.
Application of TRIZ Methodology in Diffusion Welding System Optimization
NASA Astrophysics Data System (ADS)
Ravinder Reddy, N.; Satyanarayana, V. V.; Prashanthi, M.; Suguna, N.
2017-12-01
Welding is tremendously used in metal joining processes in the manufacturing process. In recent years, diffusion welding method has significantly increased the quality of a weld. Nevertheless, diffusion welding has some extent short research and application progress. Therefore, diffusion welding has a lack of relevant information, concerned with the joining of thick and thin materials with or without interlayers, on welding design such as fixture, parameters selection and integrated design. This article intends to combine innovative methods in the application of diffusion welding design. This will help to decrease trial and error or failure risks in the welding process being guided by the theory of inventive problem solving (TRIZ) design method. This article hopes to provide welding design personnel with innovative design ideas under research and for practical application.
NASA Astrophysics Data System (ADS)
Pardowska, Anna M.; Price, John W. H.; Finlayson, Trevor R.; Ibrahim, R.
2010-11-01
Welding repairs are increasingly a structural integrity concern for aging pressure vessel and piping components. It has been demonstrated that the residual stress distribution near repair welds can be drastically different from that of the original weld. Residual stresses have a significant effect on the lifetime performance of a weld, and a reduction of these stresses is normally desirable. The aim of this paper is to investigate residual stresses in various weld repair arrangements using the non-destructive neutron diffraction technique. This research is focused on characterization of the residual stress distribution: (i) in the original weld; (ii) in a shallow toe weld repair; and (iii) after conventional post-weld heat treatment. The focus of the measurements is on the values of the subsurface strain/stress variations across the weld.
Real-time ultrasonic weld evaluation system
NASA Astrophysics Data System (ADS)
Katragadda, Gopichand; Nair, Satish; Liu, Harry; Brown, Lawrence M.
1996-11-01
Ultrasonic testing techniques are currently used as an alternative to radiography for detecting, classifying,and sizing weld defects, and for evaluating weld quality. Typically, ultrasonic weld inspections are performed manually, which require significant operator expertise and time. Thus, in recent years, the emphasis is to develop automated methods to aid or replace operators in critical weld inspections where inspection time, reliability, and operator safety are major issues. During this period, significant advances wee made in the areas of weld defect classification and sizing. Very few of these methods, however have found their way into the market, largely due to the lack of an integrated approach enabling real-time implementation. Also, not much research effort was directed in improving weld acceptance criteria. This paper presents an integrated system utilizing state-of-the-art techniques for a complete automation of the weld inspection procedure. The modules discussed include transducer tracking, classification, sizing, and weld acceptance criteria. Transducer tracking was studied by experimentally evaluating sonic and optical position tracking techniques. Details for this evaluation are presented. Classification is obtained using a multi-layer perceptron. Results from different feature extraction schemes, including a new method based on a combination of time and frequency-domain signal representations are given. Algorithms developed to automate defect registration and sizing are discussed. A fuzzy-logic acceptance criteria for weld acceptance is presented describing how this scheme provides improved robustness compared to the traditional flow-diagram standards.
Integrated LED-based luminaire for general lighting
Dowling, Kevin J.; Lys, Ihor A.; Williamson, Ryan C.; Roberge, Brian; Roberts, Ron; Morgan, Frederick; Datta, Michael Jay; Mollnow, Tomas Jonathan
2016-08-30
Lighting apparatus and methods employing LED light sources are described. The LED light sources are integrated with other components in the form of a luminaire or other general purpose lighting structure. Some of the lighting structures are formed as Parabolic Aluminum Reflector (PAR) luminaires, allowing them to be inserted into conventional sockets. The lighting structures display beneficial operating characteristics, such as efficient operation, high thermal dissipation, high output, and good color mixing.
Integrated LED-based luminare for general lighting
Dowling, Kevin J.; Lys, Ihor A.; Roberge, Brian; Williamson, Ryan C.; Roberts, Ron; Datta, Michael; Mollnow, Tomas; Morgan, Frederick M.
2013-03-05
Lighting apparatus and methods employing LED light sources are described. The LED light sources are integrated with other components in the form of a luminaire or other general purpose lighting structure. Some of the lighting structures are formed as Parabolic Aluminum Reflector (PAR) luminaires, allowing them to be inserted into conventional sockets. The lighting structures display beneficial operating characteristics, such as efficient operation, high thermal dissipation, high output, and good color mixing.
Intelligent Weld Manufacturing: Role of Integrated Computational Welding Engineering
David, Stan A.; Chen, Jian; Feng, Zhili; ...
2017-12-02
A master welder uses his sensory perceptions to evaluate the process and connect them with his/her knowledge base to take the necessary corrective measures with his/her acquired skills to make a good weld. All these actions must take place in real time. Success depends on intuition and skills, and the procedure is labor-intensive and frequently unreliable. The solution is intelligent weld manufacturing. The ultimate goal of intelligent weld manufacturing would involve sensing and control of heat source position, weld temperature, weld penetration, defect formation and ultimately control of microstructure and properties. This involves a solution to a problem (welding) withmore » many highly coupled and nonlinear variables. The trend is to use an emerging tool known as intelligent control. This approach enables the user to choose a desirable end factor such as properties, defect control, or productivity to derive the selection of process parameters such as current, voltage, or speed to provide for appropriate control of the process. Important elements of intelligent manufacturing are sensing and control theory and design, process modeling, and artificial intelligence. Significant progress has been made in all these areas. Integrated computational welding engineering (ICWE) is an emerging field that will aid in the realization of intelligent weld manufacturing. The paper will discuss the progress in process modeling, microstructure, properties, and process control and automation and the importance of ICWE. Also, control and automation strategies for friction stir welding will be discussed.« less
Intelligent Weld Manufacturing: Role of Integrated Computational Welding Engineering
DOE Office of Scientific and Technical Information (OSTI.GOV)
David, Stan A.; Chen, Jian; Feng, Zhili
A master welder uses his sensory perceptions to evaluate the process and connect them with his/her knowledge base to take the necessary corrective measures with his/her acquired skills to make a good weld. All these actions must take place in real time. Success depends on intuition and skills, and the procedure is labor-intensive and frequently unreliable. The solution is intelligent weld manufacturing. The ultimate goal of intelligent weld manufacturing would involve sensing and control of heat source position, weld temperature, weld penetration, defect formation and ultimately control of microstructure and properties. This involves a solution to a problem (welding) withmore » many highly coupled and nonlinear variables. The trend is to use an emerging tool known as intelligent control. This approach enables the user to choose a desirable end factor such as properties, defect control, or productivity to derive the selection of process parameters such as current, voltage, or speed to provide for appropriate control of the process. Important elements of intelligent manufacturing are sensing and control theory and design, process modeling, and artificial intelligence. Significant progress has been made in all these areas. Integrated computational welding engineering (ICWE) is an emerging field that will aid in the realization of intelligent weld manufacturing. The paper will discuss the progress in process modeling, microstructure, properties, and process control and automation and the importance of ICWE. Also, control and automation strategies for friction stir welding will be discussed.« less
46 CFR 56.30-30 - Brazed joints.
Code of Federal Regulations, 2010 CFR
2010-10-01
....75). Brazed socket-type joints shall be made with suitable brazing alloys. The minimum socket depth shall be sufficient for the intended service. Brazing alloy shall either be end-fed into the socket or shall be provided in the form of a preinserted ring in a groove in the socket. The brazing alloy shall...
46 CFR 56.30-30 - Brazed joints.
Code of Federal Regulations, 2013 CFR
2013-10-01
....75). Brazed socket-type joints shall be made with suitable brazing alloys. The minimum socket depth shall be sufficient for the intended service. Brazing alloy shall either be end-fed into the socket or shall be provided in the form of a preinserted ring in a groove in the socket. The brazing alloy shall...
46 CFR 56.30-30 - Brazed joints.
Code of Federal Regulations, 2011 CFR
2011-10-01
....75). Brazed socket-type joints shall be made with suitable brazing alloys. The minimum socket depth shall be sufficient for the intended service. Brazing alloy shall either be end-fed into the socket or shall be provided in the form of a preinserted ring in a groove in the socket. The brazing alloy shall...
46 CFR 56.30-30 - Brazed joints.
Code of Federal Regulations, 2014 CFR
2014-10-01
....75). Brazed socket-type joints shall be made with suitable brazing alloys. The minimum socket depth shall be sufficient for the intended service. Brazing alloy shall either be end-fed into the socket or shall be provided in the form of a preinserted ring in a groove in the socket. The brazing alloy shall...
46 CFR 56.30-30 - Brazed joints.
Code of Federal Regulations, 2012 CFR
2012-10-01
....75). Brazed socket-type joints shall be made with suitable brazing alloys. The minimum socket depth shall be sufficient for the intended service. Brazing alloy shall either be end-fed into the socket or shall be provided in the form of a preinserted ring in a groove in the socket. The brazing alloy shall...
Dutta, Shubha Ranjan; Singh, Purnima; Passi, Deepak; Patter, Pradeep
2015-09-01
To evaluate the efficacy of autologous platelet rich plasma (PRP) in regeneration of bone and to assess clinical compatibility of the material in mandibular third molar extraction socket. To compare the healing of mandibular third molar extraction wounds with and without PRP. Group A consists of the 30 patients where PRP will be placed in the extraction socket before closure of the socket. Group B consists of 30 patients who will be the control group where the extraction sockets will be closed without any intra socket medicaments. The patients would be allocated to the groups randomly. Soft tissue healing was better in study site compared to control site. The result of the study shows rapid bone regeneration in the extraction socket treated with PRP when compared with the socket without PRP. Evaluation for bone blending and trabecular bone formation started earlier in PRP site compared to control, non PRP site. Also there was less postoperative discomfort on the PRP treated side. Autologous PRP is biocompatible and has significant improved soft tissue healing, bone regeneration and increase in bone density in extraction sockets.
Clinical outcome and complications of thoracic and pelvic limb stump and socket prostheses.
Phillips, Andrew; Kulendra, Elvin; Bishop, Edith; Monk, Michelle; Parsons, Kevin; House, Arthur
2017-07-20
To describe the use, quality of life, compliance, complications, and outcome of animals fitted with stump socket prostheses. Medical records of dogs fitted with a stump socket prosthesis were reviewed. Functional outcome, quality of life and complications were retrospectively assessed from an owner questionnaire. Thirteen stump socket prostheses (12 dogs) were fitted for a variety of reasons including trauma, congenital abnormalities, and neoplasia. Eight dogs had a good outcome overall and four a poor outcome. Quality of life (QOL) remained good or excellent in 10/12 dogs. Nine complications were seen in 7/12 dogs, most were manageable; surgical wound complications (n = 2) and pressures sores (n = 4) were the most frequently encountered. One dog suffered multiple complications. Thoracic and pelvic limb stump socket prostheses had a similar complication rate, however all animals with a poor outcome had a thoracic limb stump socket prosthesis; two were small breed dogs (under 10 kg) and two had bilateral thoracic limb abnormalities. Stump socket prostheses are feasible and versatile in animals. In correctly selected cases, good to excellent outcomes are possible. However, complications are frequent but often manageable. Further investigations are required into the risk factors for poor outcomes and prospective studies are required to assess changes in biomechanics, function, and QOL before and after fitting of a stump socket prosthesis. Until further evidence is available, careful consideration should be given before fitting bilateral thoracic limb stump socket prostheses or thoracic limb stump socket prostheses to small breed dogs.
Boone, David A; Kobayashi, Toshiki; Chou, Teri G; Arabian, Adam K; Coleman, Kim L; Orendurff, Michael S; Zhang, Ming
2013-04-01
Alignment - the process and measured orientation of the prosthetic socket relative to the foot - is important for proper function of a transtibial prosthesis. Prosthetic alignment is performed by prosthetists using visual gait observation and amputees' feedback. The aim of this study was to investigate the effect of transtibial prosthesis malalignment on the moments measured at the base of the socket: the socket reaction moments. Eleven subjects with transtibial amputation were recruited from the community. An instrumented prosthesis alignment component was used to measure socket reaction moments during ambulation under 17 alignment conditions, including nominally aligned using conventional clinical methods, and angle perturbations of 3° and 6° (flexion, extension, abduction, and adduction) and translation perturbations of 5mm and 10mm (anterior, posterior, lateral, and medial) referenced from the nominal alignment. Coronal alignment perturbations caused systematic changes in the coronal socket reaction moments. All angle and translation perturbations revealed statistically significant differences on coronal socket reaction moments compared to the nominal alignment at 30% and 75% of stance phase (P<0.05). The effect of sagittal alignment perturbations on sagittal socket reaction moments was not as responsive as that of the coronal perturbations. The sagittal angle and translation perturbations of the socket led to statistically significant changes in minimum moment, maximum moment, and moments at 45% of stance phase in the sagittal plane. Therefore, malalignment affected the socket reaction moments in amputees with transtibial prostheses. Copyright © 2012 Elsevier B.V. All rights reserved.
An Amino Acid Packing Code for α-helical Structure and Protein Design
Joo, Hyun; Chavan, Archana G.; Phan, Jamie; Day, Ryan; Tsai, Jerry
2012-01-01
This work demonstrates that all packing in α-helices can be simplified to repetitive patterns of a single motif: the knob-socket. Using the precision of Voronoi Polyhedra/Deluaney Tessellations to identify contacts, the knob-socket is a 4 residue tetrahedral motif: a knob residue on one α-helix packs into the 3 residue socket on another α-helix. The principle of the knob-socket model relates the packing between levels of protein structure: the intra-helical packing arrangements within secondary structure that permit inter-helix tertiary packing interactions. Within an α-helix, the 3 residue sockets arrange residues into a uniform packing lattice. Inter-helix packing results from a definable pattern of interdigitated knob-socket motifs between 2 α-helices. Furthermore, the knob-socket model classifies 3 types of sockets: 1) free: favoring only intra-helical packing, 2) filled: favoring inter-helical interactions and 3) non: disfavoring α-helical structure. The amino acid propensities in these 3 socket classes essentially represent an amino acid code for structure in α-helical packing. Using this code, a novel yet straightforward approach for the design of α-helical structure was used to validate the knob-socket model. Unique sequences for 3 peptides were created to produce a predicted amount of α-helical structure: mostly helical, some helical, and no-helix. These 3 peptides were synthesized and helical content assessed using CD spectroscopy. The measured α-helicity of each peptide was consistent with the expected predictions. These results and analysis demonstrate that the knob-socket motif functions as the basic unit of packing and presents an intuitive tool to decipher the rules governing packing in protein structure. PMID:22426125
Das, Swati; Jhingran, Rajesh; Bains, Vivek Kumar; Madan, Rohit; Srivastava, Ruchi; Rizvi, Iram
2016-01-01
Objectives: This study was primarily designed to determine the clinico-radiographic efficacy of platelet-rich fibrin (PRF) and beta-tri-calcium phosphate with collagen (β-TCP-Cl) in preserving extraction sockets. Materials and Methods: For Group I (PRF), residual sockets (n = 15) were filled with autologous PRF obtained from patients' blood; and for Group II (β-TCP-Cl), residual sockets (n = 15) were filled with β-TCP-Cl. For the sockets randomly selected for Group II (β-TCP-Cl), the reshaped Resorbable Tissue Replacement cone was inserted into the socket. Results: Clinically, there was a significantly greater decrease in relative socket depth, but apposition in midcrestal height in Group II (β-TCP-Cl) as compared to Group I (PRF), whereas more decrease in buccolingual width of Group I (PRF) than Group II (β-TCP-Cl) after 6 months. Radiographically, the mean difference in socket height, residual ridge, and width (coronal, middle, and apical third of socket) after 6 months was higher in Group I (PRF) as compared to Group II (β-TCP-Cl). The mean density (in Hounsfield Units) at coronal, middle, and apical third of socket was higher in Group I (PRF) as compared to Group II (β-TCP-Cl). There were statistically significant apposition and resorption for Group I (PRF) whereas nonsignificant resorption and significant apposition for Group II (β-TCP-Cl) in buccal and lingual/palatal cortical plate, respectively, at 6 months on computerized tomography scan. Conclusion: The use of either autologous PRF or β-TCP-Cl was effective in socket preservation. Results obtained from PRF were almost similar to β-TCP-Cl; therefore being autologous, nonimmune, cost-effective, easily procurable regenerative biomaterial, PRF proves to be an insight into the future biofuel for regeneration. PMID:27095909
Das, Swati; Jhingran, Rajesh; Bains, Vivek Kumar; Madan, Rohit; Srivastava, Ruchi; Rizvi, Iram
2016-01-01
This study was primarily designed to determine the clinico-radiographic efficacy of platelet-rich fibrin (PRF) and beta-tri-calcium phosphate with collagen (β-TCP-Cl) in preserving extraction sockets. For Group I (PRF), residual sockets (n = 15) were filled with autologous PRF obtained from patients' blood; and for Group II (β-TCP-Cl), residual sockets (n = 15) were filled with β-TCP-Cl. For the sockets randomly selected for Group II (β-TCP-Cl), the reshaped Resorbable Tissue Replacement cone was inserted into the socket. Clinically, there was a significantly greater decrease in relative socket depth, but apposition in midcrestal height in Group II (β-TCP-Cl) as compared to Group I (PRF), whereas more decrease in buccolingual width of Group I (PRF) than Group II (β-TCP-Cl) after 6 months. Radiographically, the mean difference in socket height, residual ridge, and width (coronal, middle, and apical third of socket) after 6 months was higher in Group I (PRF) as compared to Group II (β-TCP-Cl). The mean density (in Hounsfield Units) at coronal, middle, and apical third of socket was higher in Group I (PRF) as compared to Group II (β-TCP-Cl). There were statistically significant apposition and resorption for Group I (PRF) whereas nonsignificant resorption and significant apposition for Group II (β-TCP-Cl) in buccal and lingual/palatal cortical plate, respectively, at 6 months on computerized tomography scan. The use of either autologous PRF or β-TCP-Cl was effective in socket preservation. Results obtained from PRF were almost similar to β-TCP-Cl; therefore being autologous, nonimmune, cost-effective, easily procurable regenerative biomaterial, PRF proves to be an insight into the future biofuel for regeneration.
Quantification of rectifications for the Northwestern University Flexible Sub-Ischial Vacuum Socket.
Fatone, Stefania; Johnson, William Brett; Tran, Lilly; Tucker, Kerice; Mowrer, Christofer; Caldwell, Ryan
2017-06-01
The fit and function of a prosthetic socket depend on the prosthetist's ability to design the socket's shape to distribute load comfortably over the residual limb. We recently developed a sub-ischial socket for persons with transfemoral amputation: the Northwestern University Flexible Sub-Ischial Vacuum Socket. This study aimed to quantify the rectifications required to fit the Northwestern University Flexible Sub-Ischial Vacuum Socket to teach the technique to prosthetists as well as provide a computer-aided design-computer-aided manufacturing option. Development project. A program was used to align scans of unrectified and rectified negative molds and calculate shape change as a result of rectification. Averaged rectifications were used to create a socket template, which was shared with a central fabrication facility engaged in provision of Northwestern University Flexible Sub-Ischial Vacuum Sockets to early clinical adopters. Feedback regarding quality of fitting was obtained. Rectification maps created from 30 cast pairs of successfully fit Northwestern University Flexible Sub-Ischial Vacuum Sockets confirmed that material was primarily removed from the positive mold in the proximal-lateral and posterior regions. The template was used to fabricate check sockets for 15 persons with transfemoral amputation. Feedback suggested that the template provided a reasonable initial fit with only minor adjustments. Rectification maps and template were used to facilitate teaching and central fabrication of the Northwestern University Flexible Sub-Ischial Vacuum Socket. Minor issues with quality of initial fit achieved with the template may be due to inability to adjust the template to patient characteristics (e.g. tissue type, limb shape) and/or the degree to which it represented a fully mature version of the technique. Clinical relevance Rectification maps help communicate an important step in the fabrication of the Northwestern University Flexible Sub-Ischial Vacuum Socket facilitating dissemination of the technique, while the average template provides an alternative fabrication option via computer-aided design-computer-aided manufacturing and central fabrication.
Sewell, Philip; Noroozi, Siamak; Vinney, John; Amali, Ramin; Andrews, Stephen
2012-01-01
It has been recognised in a review of the developments of lower-limb prosthetic socket fitting processes that the future demands new tools to aid in socket fitting. This paper presents the results of research to design and clinically test an artificial intelligence approach, specifically inverse problem analysis, for the determination of the pressures at the limb/prosthetic socket interface during stance and ambulation. Inverse problem analysis is based on accurately calculating the external loads or boundary conditions that can generate a known amount of strain, stresses or displacements at pre-determined locations on a structure. In this study a backpropagation artificial neural network (ANN) is designed and validated to predict the interfacial pressures at the residual limb/socket interface from strain data collected from the socket surface. The subject of this investigation was a 45-year-old male unilateral trans-tibial (below-knee) traumatic amputee who had been using a prosthesis for 22 years. When comparing the ANN predicted interfacial pressure on 16 patches within the socket with actual pressures applied to the socket there is shown to be 8.7% difference, validating the methodology. Investigation of varying axial load through the subject's prosthesis, alignment of the subject's prosthesis, and pressure at the limb/socket interface during walking demonstrates that the validated ANN is able to give an accurate full-field study of the static and dynamic interfacial pressure distribution. To conclude, a methodology has been developed that enables a prosthetist to quantitatively analyse the distribution of pressures within the prosthetic socket in a clinical environment. This will aid in facilitating the "right first time" approach to socket fitting which will benefit both the patient in terms of comfort and the prosthetist, by reducing the time and associated costs of providing a high level of socket fit. Copyright © 2011 Elsevier B.V. All rights reserved.
Leong, R.
1993-06-22
The invention is a receptacle for a three prong electrical plug which has either a tubular or U-shaped grounding prong. The inventive receptacle has a grounding prong socket which is sufficiently spacious to prevent the socket from significantly stretching when a larger, U-shaped grounding prong is inserted into the socket, and having two ridges to allow a snug fit when a smaller tubular shape grounding prong is inserted into the socket. The two ridges are made to prevent the socket from expanding when either the U-shaped grounding prong or the tubular grounding prong is inserted.
Leong, Robert
1993-01-01
The invention is a receptacle for a three prong electrical plug which has either a tubular or U-shaped grounding prong. The inventive receptacle has a grounding prong socket which is sufficiently spacious to prevent the socket from significantly stretching when a larger, U-shaped grounding prong is inserted into the socket, and having two ridges to allow a snug fit when a smaller tubular shape grounding prong is inserted into the socket. The two ridges are made to prevent the socket from expanding when either the U-shaped grounding prong or the tubular grounding prong is inserted.
Friction Stir Welding of Dissimilar Al/Al and Al/Non-Al Alloys: A Review
NASA Astrophysics Data System (ADS)
Wang, Xiangbin; Pan, Yi; Lados, Diana A.
2018-05-01
Friction stir welding is a solid-state welding technique that has many advantages over traditional fusion welding, and has been widely adopted in the aerospace and automotive industries. This article reviews research developments in friction stir welding of dissimilar alloys systems, including combinations of aluminum alloys with Mg alloys, Cu, and steel. Microstructural evolution, hardness, tensile and fatigue properties, residual stresses, and corrosion behavior of dissimilar welds will be reported. The effects of processing parameters such as tool rotation and traverse speeds, tool position, material position, and tool geometry on the weld quality are also presented. Discussions on future research directions in friction stir welding will also be provided in the context of existing literature and future high-integrity applications.
Ahn, Jae-Jin; Shin, Hong-In
2008-01-01
To investigate postextraction bone formation over time in both diseased and healthy sockets. Core specimens of healing tissues following tooth extraction were obtained at the time of implant placement in patients treated between October 2005 and December 2007. A disease group and a control group were classified according to socket examination at the time of extraction. The biopsy specimens were analyzed histomorphometrically to measure the dimensional changes among 3 tissue types: epithelial layer, connective tissue area, and new bone tissue area. Fifty-five specimens from sites of previously advanced periodontal disease from 45 patients were included in the disease group. Another 12 specimens of previously healthy extraction sockets were collected from 12 different patients as a control. The postextraction period of the disease group varied from 2 to 42 weeks. In the disease group, connective tissue occupied most of the socket during the first 4 weeks. New bone area progressively replaced the connective tissue area after the first 4 weeks. The area proportion of new bone tissue exceeded that of connective tissue by 14 weeks. After 20 weeks, most extraction sockets in the disease group demonstrated continuous new bone formation. The control group exhibited almost complete socket healing after 10 weeks, with no more new bone formation after 20 weeks. Osseous regeneration in the diseased sockets developed more slowly than in the disease-free sockets. After 16 weeks, new bone area exceeded 50% of the total newly regenerated tissue in the sockets with severe periodontal destruction. In the control group, after 8 weeks, new bone area exceeded 50% of the total tissue.
Kobayashi, Toshiki; Orendurff, Michael S; Boone, David A
2013-09-27
The alignment of a lower-limb prosthesis is critical to the successful prosthetic fitting and utilization by the wearer. Loads generated by the socket applied to the residual limb while walking are thought to be different in transfemoral and knee-disarticulation prostheses. The aim of this case series was to compare the socket reaction moments between transfemoral and knee-disarticulation prostheses and to investigate the effect of alignment changes on them. Two amputees, one with a transfemoral prosthesis and another with a knee-disarticulation prosthesis, participated in this study. A Smart Pyramid™ was used to measure socket reaction moments while walking under 9 selected alignment conditions; including nominally aligned, angle malalignments of 6° (flexion, extension, abduction and adduction) and translation malalignments of 15 mm (anterior, posterior, medial and lateral) of the socket relative to the foot. This study found that the pattern of the socket reaction moments was similar between transfemoral and knee-disarticulation prostheses. An extension moment in the sagittal plane and a varus moment in the coronal plane were dominant during stance under the nominally aligned condition. This study also demonstrated that alignment changes might have consistent effects on the socket reaction moments in transfemoral and knee-disarticulation prostheses. Extension and posterior translation of the socket resulted in increases in an extension moment, while abduction and lateral translation of the socket resulted in increases in a varus moment. The socket reaction moments may potentially serve as useful biomechanical parameters to evaluate alignment in transfemoral and knee-disarticulation prostheses. Copyright © 2013 Elsevier Ltd. All rights reserved.
Characterization of interfacial socket pressure in transhumeral prostheses: A case series.
Schofield, Jonathon S; Schoepp, Katherine R; Williams, Heather E; Carey, Jason P; Marasco, Paul D; Hebert, Jacqueline S
2017-01-01
One of the most important factors in successful upper limb prostheses is the socket design. Sockets must be individually fabricated to arrive at a geometry that suits the user's morphology and appropriately distributes the pressures associated with prosthetic use across the residual limb. In higher levels of amputation, such as transhumeral, this challenge is amplified as prosthetic weight and the physical demands placed on the residual limb are heightened. Yet, in the upper limb, socket fabrication is largely driven by heuristic practices. An analytical understanding of the interactions between the socket and residual limb is absent in literature. This work describes techniques, adapted from lower limb prosthetic research, to empirically characterize the pressure distribution occurring between the residual limb and well-fit transhumeral prosthetic sockets. A case series analyzing the result of four participants with transhumeral amputation is presented. A Tekscan VersaTek pressure measurement system and FaroArm Edge coordinate measurement machine were employed to capture socket-residual limb interface pressures and geometrically register these values to the anatomy of participants. Participants performed two static poses with their prosthesis under two separate loading conditions. Surface pressure maps were constructed from the data, highlighting pressure distribution patterns, anatomical locations bearing maximum pressure, and the relative pressure magnitudes. Pressure distribution patterns demonstrated unique characteristics across the four participants that could be traced to individual socket design considerations. This work presents a technique that implements commercially available tools to quantitatively characterize upper limb socket-residual limb interactions. This is a fundamental first step toward improved socket designs developed through informed, analytically-based design tools.
Characterization of interfacial socket pressure in transhumeral prostheses: A case series
Schoepp, Katherine R.; Williams, Heather E.; Carey, Jason P.; Marasco, Paul D.
2017-01-01
One of the most important factors in successful upper limb prostheses is the socket design. Sockets must be individually fabricated to arrive at a geometry that suits the user’s morphology and appropriately distributes the pressures associated with prosthetic use across the residual limb. In higher levels of amputation, such as transhumeral, this challenge is amplified as prosthetic weight and the physical demands placed on the residual limb are heightened. Yet, in the upper limb, socket fabrication is largely driven by heuristic practices. An analytical understanding of the interactions between the socket and residual limb is absent in literature. This work describes techniques, adapted from lower limb prosthetic research, to empirically characterize the pressure distribution occurring between the residual limb and well-fit transhumeral prosthetic sockets. A case series analyzing the result of four participants with transhumeral amputation is presented. A Tekscan VersaTek pressure measurement system and FaroArm Edge coordinate measurement machine were employed to capture socket-residual limb interface pressures and geometrically register these values to the anatomy of participants. Participants performed two static poses with their prosthesis under two separate loading conditions. Surface pressure maps were constructed from the data, highlighting pressure distribution patterns, anatomical locations bearing maximum pressure, and the relative pressure magnitudes. Pressure distribution patterns demonstrated unique characteristics across the four participants that could be traced to individual socket design considerations. This work presents a technique that implements commercially available tools to quantitatively characterize upper limb socket-residual limb interactions. This is a fundamental first step toward improved socket designs developed through informed, analytically-based design tools. PMID:28575012
A precision analogue integrator system for heavy current measurement in MFDC resistance spot welding
NASA Astrophysics Data System (ADS)
Xia, Yu-Jun; Zhang, Zhong-Dian; Xia, Zhen-Xin; Zhu, Shi-Liang; Zhang, Rui
2016-02-01
In order to control and monitor the quality of middle frequency direct current (MFDC) resistance spot welding (RSW), precision measurement of the welding current up to 100 kA is required, for which Rogowski coils are the only viable current transducers at present. Thus, a highly accurate analogue integrator is the key to restoring the converted signals collected from the Rogowski coils. Previous studies emphasised that the integration drift is a major factor that influences the performance of analogue integrators, but capacitive leakage error also has a significant impact on the result, especially in long-time pulse integration. In this article, new methods of measuring and compensating capacitive leakage error are proposed to fabricate a precision analogue integrator system for MFDC RSW. A voltage holding test is carried out to measure the integration error caused by capacitive leakage, and an original integrator with a feedback adder is designed to compensate capacitive leakage error in real time. The experimental results and statistical analysis show that the new analogue integrator system could constrain both drift and capacitive leakage error, of which the effect is robust to different voltage levels of output signals. The total integration error is limited within ±0.09 mV s-1 0.005% s-1 or full scale at a 95% confidence level, which makes it possible to achieve the precision measurement of the welding current of MFDC RSW with Rogowski coils of 0.1% accuracy class.
Haraji, Afshin; Rakhshan, Vahid; Khamverdi, Naiemeh; Alishahi, Hadiseh Khanzadeh
2013-01-01
To assess the effects of intra-alveolar application of chlorhexidine gel on the incidence of alveolar osteitis (dry socket) and the severity of postsurgical pain. A total of 160 impacted mandibular third molars were extracted in 80 patients enrolled in this trial. In each subject, a socket was randomly selected and packed to the crest of the alveolar ridge with a gelatin sponge dressing saturated in 0.2% chlorhexidine gel. The contralateral socket was packed with a dry dressing as the placebo. None of the included patients took antibiotics or analgesics. The occurrence of dry socket and patients' pain levels were assessed at the first and third postoperative days. The data were analyzed using Spearman correlation coefficient, McNemar, Wilcoxon, and chi-square tests. Chlorhexidine gel significantly reduced dry socket incidence from 32.6% to 11.3% (P ≤ .001 [McNemar and chi-square], absolute risk reduction = 21.2%, relative risk reduction = 65.4%, odds ratio = 0.263, relative risk = 0.345). It also significantly relieved postoperative pain on both sides in all the patients (P ≤ .001 [Wilcoxon]) and also in the 54 subjects who did not develop dry socket (P ≤ .001 [Wilcoxon]). Besides decreasing the incidence of dry socket, chlorhexidine gel can reduce postsurgical pain in patients with and without dry socket.
Song, Xiaocun; Zhou, Jixue; Liu, Hongtao; Yang, Yuansheng
2018-01-01
Electrical connection of dissimilar metals will lead to galvanic corrosion. Therefore, overall surface treatment is necessary for the protection of dissimilar metal welded parts. However, serious unbalanced reactions may occur during overall surface treatment, which makes it difficult to prepare integral coating. In this paper, an overall ceramic coating was fabricated by plasma electrolytic oxidation to wrap the 6061–7075 welded part integrally. Moreover, the growth mechanism of the coating on different areas of the welded part was studied based on the dielectric breakdown theory. The reaction sequence of each area during the treatment was verified through specially designed dielectric breakdown tests. The results showed that the high impedance overall of ceramic coating can inhibit the galvanic corrosion of the 6061–7075 welded part effectively. PMID:29301306
NASA Astrophysics Data System (ADS)
Bag, S.; de, A.
2010-09-01
The transport phenomena based heat transfer and fluid flow calculations in weld pool require a number of input parameters. Arc efficiency, effective thermal conductivity, and viscosity in weld pool are some of these parameters, values of which are rarely known and difficult to assign a priori based on the scientific principles alone. The present work reports a bi-directional three-dimensional (3-D) heat transfer and fluid flow model, which is integrated with a real number based genetic algorithm. The bi-directional feature of the integrated model allows the identification of the values of a required set of uncertain model input parameters and, next, the design of process parameters to achieve a target weld pool dimension. The computed values are validated with measured results in linear gas-tungsten-arc (GTA) weld samples. Furthermore, a novel methodology to estimate the overall reliability of the computed solutions is also presented.
A smartphone photogrammetry method for digitizing prosthetic socket interiors.
Hernandez, Amaia; Lemaire, Edward
2017-04-01
Prosthetic CAD/CAM systems require accurate 3D limb models; however, difficulties arise when working from the person's socket since current 3D scanners have difficulties scanning socket interiors. While dedicated scanners exist, they are expensive and the cost may be prohibitive for a limited number of scans per year. A low-cost and accessible photogrammetry method for socket interior digitization is proposed, using a smartphone camera and cloud-based photogrammetry services. 15 two-dimensional images of the socket's interior are captured using a smartphone camera. A 3D model is generated using cloud-based software. Linear measurements were comparing between sockets and the related 3D models. 3D reconstruction accuracy averaged 2.6 ± 2.0 mm and 0.086 ± 0.078 L, which was less accurate than models obtained by high quality 3D scanners. However, this method would provide a viable 3D digital socket reproduction that is accessible and low-cost, after processing in prosthetic CAD software. Clinical relevance The described method provides a low-cost and accessible means to digitize a socket interior for use in prosthetic CAD/CAM systems, employing a smartphone camera and cloud-based photogrammetry software.
Computer design synthesis of a below knee-Syme prosthesis
NASA Technical Reports Server (NTRS)
Elangovan, P. T.; Ghista, D. N.; Alwar, R. S.
1979-01-01
A detailed design synthesis analysis of the BK Syme prosthesis is provided, to determine the socket's cutout orientation size and shape, cutout fillet shape, socket wall thickness distribution and the reinforced fiber distribution in the socket wall, for a minimally stressed structurally safe lightweight prosthesis. For analysis purposes, the most adverse socket loading is obtained at the push-off stage of gait; this loading is idealized as an axial in-plane loading on the bottom edge of the circular cylindrical socket shell whose top edge is considered fixed. Finite element stress analysis of the socket shell (with uniform and graded wall thickness) are performed for various orientations of the cutout and for various types of corner fillets. A lateral cutout with a streamline fillet is recommended. The wall material (i.e., thickness) distribution is determined so as to minimize the stresses, while ensuring that the wall material's stress limits are not exceeded. For such a maximally stressed lightweight socket shell, the panels in the neighborhood of the cutout are checked to ensure that they do not buckle under their acquired stresses. A fiber-reinforced laminated composite socket shell is also analyzed in order to recommend optimum variables in orientations and densities of reinforcing fibers.
Socket stars: UBVRJIK radial profiles
NASA Astrophysics Data System (ADS)
Schaefer, Bradley E.
1995-05-01
Visual inspectin of stars embedded in H II nebulae has shown a significant fraction to be surrounded by nearly symmetric extended regions within which the nebular brightness is apparently significantly fainter than is typical for the surrounding area. These 'socket stars' might be caused by a bubble in the nebula blown out by a stellar wind or they might be caused by a circumstellar envelope of dust hiding the emission behind the star. As such, the sockets could be the first manifestation of a previously unknown component of pre-main-sequence stars. Unfortunately, no quantitative proof of the existence of sockets has been presented. To fill this need, I have imaged 10 socket stars and six background stars with CCD cameras and infrared array cameras. From these images, I have constructed radial plots which should reveal dips in brightness immediately outside the seeing disk. The radial plots do not show any evidence for the existence of sockets. A detailed examination of the photographs orginally used to identify the sockets show that the causes of these reports are (1) artifacts resulting from the photographic process of dodging and (2) random coincidence of stars with local minima in nebular brightness. Thus, I conclude that 'socket stars' do not exist.
Robot friendly probe and socket assembly
NASA Technical Reports Server (NTRS)
Nyberg, Karen L. (Inventor)
1994-01-01
A probe and socket assembly for serving as a mechanical interface between structures is presented. The assembly comprises a socket having a housing adapted for connection to a first supporting structure and a probe which is readily connectable to a second structure and is designed to be easily grappled and manipulated by a robotic device for insertion and coupling with the socket. Cooperable automatic locking means are provided on the probe shaft and socket housing for automatically locking the probe in the socket when the probe is inserted a predetermined distance. A second cooperable locking means on the probe shaft and housing are adapted for actuation after the probe has been inserted the predetermined distance. Actuation means mounted on the probe and responsive to the grip of the probe handle by a gripping device, such as a robot for conditioning the probe for insertion and are also responsive to release of the grip of the probe handle to actuate the second locking means to provide a hard lock of the probe in the socket.
Jambhekar, Shantanu; Kernen, Florian; Bidra, Avinash S
2015-05-01
Several biomaterials and techniques have been reported for socket grafting and alveolar ridge preservation. However, the evidence for clinical and histologic outcomes for socket grafting with different types of materials in flapless extraction is not clear. The purpose of this systematic review was to analyze the outcomes of a socket grafting procedure performed with flapless extraction of teeth in order to determine which graft material results in the least loss of socket dimensions, the maximum amount of vital bone, the least remnant graft material, and the least amount of connective tissue after a minimum of 12 weeks of healing. Secondary outcomes, including the predictability of regenerating deficient buccal bone, necessity of barrier membranes, and coverage with autogenous soft tissue graft, were also evaluated. An electronic search for articles in the English-language literature was performed independently by multiple investigators using a systematic search process with the PubMed search engine. After applying predetermined inclusion and exclusion criteria, the final list of randomized controlled clinical trials (RCTs) for flapless extraction and socket grafting was analyzed to derive results for the various objectives of the study. The initial electronic search resulted in 2898 titles. The systematic application of inclusion and exclusion criteria resulted in 32 RCTs studying 1354 sockets, which addressed the clinical and histologic outcomes of flapless extraction with socket grafting and provided dimensional and histologic information at or beyond the 12-week reentry period. From these RCTs, the mean loss of buccolingual width at the ridge crest was lowest for xenografts (1.3 mm), followed by allografts (1.63 mm), alloplasts (2.13 mm), and sockets without any socket grafting (2.79 mm). Only 3 studies reported on loss of width at 3 mm below the ridge crest. The mean loss of buccal wall height from the ridge crest was lowest for xenografts (0.57 mm) and allografts (0.58 mm), followed by alloplasts (0.77 mm) and sockets without any grafting (1.74 mm). The mean histologic outcomes at or beyond the 12-week reentry period revealed the highest vital bone content for sockets grafted with alloplasts (45.53%), followed by sockets with no graft material (41.07%), xenografts (35.72%), and allografts (29.93%). The amount of remnant graft material was highest for sockets grafted with allografts (21.75%), followed by xenografts (19.3%) and alloplasts (13.67%). The highest connective tissue content at the time of reentry was seen for sockets with no grafting (52.53%), followed by allografts (51.03%), xenografts (44.42%), and alloplast (38.39%). Data for new and emerging biomaterials such as cell therapy and tissue regenerative materials were not amenable to calculations because of biomaterial heterogeneity and small sample sizes. After flapless extraction of teeth, and using a minimum healing period of 12 weeks as a temporal measure, xenografts and allografts resulted in the least loss of socket dimensions compared to alloplasts or sockets with no grafting. Histologic outcomes after a minimum of 12 weeks of healing showed that sockets grafted with alloplasts had the maximum amount of vital bone and the least amount of remnant graft material and remnant connective tissue. There is a limited but emerging body of evidence for the predictable regeneration of deficient buccal bone with socket grafting materials, need for barrier membranes, use of tissue engineering, and use of autogenous soft tissue grafts from the palate to cover the socket. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
Tethering sockets and wrenches
NASA Technical Reports Server (NTRS)
Johnson, E. P.
1990-01-01
The tethering of sockets and wrenches was accomplished to improve the safety of working over motor segments. To accomplish the tethering of the sockets to the ratchets, a special design was implemented in which a groove was machined into each socket. Each socket was then fitted with a snap ring that can spin around the machined groove. The snap ring is tethered to the handle of the ratchet. All open end wrenches are also tethered to the ratchet or to the operator, depending upon the type. Tests were run to ensure that the modified tools meet torque requirements. The design was subsequently approved by Space Safety.
Fee, L
2017-04-21
Socket preservation maintains bone volume post-extraction in anticipation of an implant placement or fixed partial denture pontic site. This procedure helps compensate for the resorption of the facial bone wall. Socket preservation should be considered when implant placement needs to be delayed for patient or site-related reasons. The ideal healing time before implant placement is six months. Socket preservation can reduce the need for later bone augmentation. By reducing bone resorption and accelerating bone formation it increases implant success and survival. Biomaterials for socket grafting including autograft, allograft, xenograft and alloplast. A bone substitute with a low substitution rate is recommended.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-15
... with medium screw base sockets, as well as pin-based sockets. (42 U.S.C. 6295(ff)(2)-(3)) The statute... (including candelabra screw base sockets) by January 1, 2007, and if DOE failed to issue such standards by... standards for light kits with sockets other than medium-screw base or pin-based fluorescent lamps in the CFR...
Timeframe of socket cortication after tooth extraction: A retrospective radiographic study.
Bertl, Kristina; Kukla, Edmund Benjamin; Albugami, Rajaa; Beck, Florian; Gahleitner, André; Stavropoulos, Andreas
2018-01-01
To assess the timeframe between tooth extraction and radiographically detectable socket cortication in humans. Two hundred and fifty patients with a CT scan ≤36 months after tooth extraction were included. First, three orthoradial multiplanar reconstruction slices, representing the major part of the extraction socket, were scored regarding the degree of bone healing as (i) healed, that is, complete/continuous cortication of the socket entrance, or (ii) non-healed. Thereafter, based on the results of all three slices, the stage of cortication of the extraction socket, as one unit, was classified as (i) non-corticated, that is, all three slices judged as non-healed, (ii) partially corticated, that is, 1 or 2 slices judged as non-healed, or (iii) completely corticated, that is, all three slices judged as healed. The possible effect of several independent parameters, that is, age, gender, timeframe between tooth extraction and CT scan, tooth type, extent of radiographic bone loss of the extracted tooth, tooth-gap type, smoking status, presence of any systemic disease, and medication intake, on cortication status was statistically evaluated. Three to 6 months after tooth extraction, 27% of the sockets were judged as non-corticated and 53% were judged as partially corticated. After 9-12 months, >80% of the sockets were corticated, while some incompletely corticated sockets were detected up to 15 months after extraction. Each additional month after tooth extraction contributed significantly to a higher likelihood of a more advanced stage of cortication, while radiographic bone loss ≥75% significantly prolonged cortication time; no other independent variable had a significant effect. The results indicate a considerably long timeframe until complete cortication of an extraction socket, that is, 3-6 months after tooth extraction 3 of 4 sockets were still not completely corticated, and only after 9-12 months, complete cortication was observed in about 80% of the sockets. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Girish Kumar, N; Chaudhary, Rupanzal; Kumar, Ish; Arora, Srimathy S; Kumar, Nilesh; Singh, Hem
2018-06-01
The purpose of this study is to evaluate the efficacy of Platelet Rich Fibrin (PRF) as a socket plug with or without use of Plaster of Paris (POP) as bone substitute to preserve the alveolar ridge post-extraction. A prospective randomised single blind controlled study, was conducted for 18 months from November 2014 to May 2016 on 48 patients requiring extraction. All teeth were extracted atraumatically using periotomes and luxators without raising mucoperiosteal flap. Sockets were randomly allotted to groups A, B and C. Group A sockets were chosen as control, where figure of eight suture was placed. In group B sockets, PRF obtained by centrifugation was used as a socket plug and stabilised with figure of eight suture. Group C sockets were filled with POP and then covered with PRF. The socket was then closed with a figure of eight suture. Patients were informed of need for 6 months follow-up. Ninety sockets in 48 patients were subjected to our study. We found that results in the sockets where we have grafted POP showed better ridge preservation and post-operative comfort even though the difference in ridge resorption between the three groups was not statistically significant. Powered by Editorial Manager® and ProduXion Manager® from the Aries Systems Corporation. Atraumatic extraction may minimise the post-operative pain and discomfort to patient as well as the post-extraction alveolar height and width changes. The use of PRF and/or bone substitute even though clinically contributes to better post-operative healing and minimal loss of alveolar width and height, the values were not statistically significant.
Aluminum U-groove weld enhancement based on experimental stress analyses
NASA Technical Reports Server (NTRS)
Verderaime, V.; Vaughan, R.
1995-01-01
Though butt-welds are among the most preferred joining methods in aerostructures because of their sealing and assembly integrity and general elastic performance; their inelastic mechanics are generally the least understood. This study investigated experimental strain distributions across a thick aluminum U-grooved weld and identified two weld process considerations for improving the multipass weld strength. The extreme thermal expansion and contraction gradient of the fusion heat input across the tab thickness between the grooves produce severe peaking, which induces bending moment under uniaxial loading. The filler strain hardening decreased with increasing filler pass sequence. These combined effects reduce the weld strength, and a depeaking index model was developed to select filler pass thicknesses, pass numbers, and sequences to improve the welding process results over the current normal weld schedule.
NASA Astrophysics Data System (ADS)
Adalarasan, R.; Santhanakumar, M.
2015-01-01
In the present work, yield strength, ultimate strength and micro-hardness of the lap joints formed with Al 6061 alloy sheets by using the processes of Tungsten Inert Gas (TIG) welding and Metal Inert Gas (MIG) welding were studied for various combinations of the welding parameters. The parameters taken for study include welding current, voltage, welding speed and inert gas flow rate. Taguchi's L9 orthogonal array was used to conduct the experiments and an integrated technique of desirability grey relational analysis was disclosed for optimizing the welding parameters. The ignored robustness in desirability approach is compensated by the grey relational approach to predict the optimal setting of input parameters for the TIG and MIG welding processes which were validated through the confirmation experiments.
Finite element analysis of the contact interface between trans-femoral stump and prosthetic socket.
Zhang, Linlin; Zhu, Ming; Shen, Ling; Zheng, Feng
2013-01-01
Transfemoral amputees need prosthetic devices after amputation surgery, and the interface pressure between the residual limb and prosthetic socket has a significant effect on an amputee's satisfaction and comfort. The purpose of this study was to build a nonlinear finite element model to investigate the interface pressure between the above-knee residual limb and its prosthetic socket. The model was three-dimensional (3D) with consideration of nonlinear boundary conditions. Contact analysis was used to simulate the friction conditions between skin and the socket. The normal stresses up to 80.57 kPa at the distal end of the soft tissue. The longitudinal and circumferential shear stress distributions at the limb-socket interface were also simulated. This study explores the influences of load transfer between trans-femoral residual limb and its prosthetic socket.
CAD/CAM transtibial prosthetic sockets from central fabrication facilities: How accurate are they?
Sanders, Joan E.; Rogers, Ellen L.; Sorenson, Elizabeth A.; Lee, Gregory S.; Abrahamson, Daniel C.
2014-01-01
This research compares transtibial prosthetic sockets made by central fabrication facilities with their corresponding American Academy of Orthotists and Prosthetists (AAOP) electronic shape files and assesses the central fabrication process. We ordered three different socket shapes from each of 10 manufacturers. Then we digitized the sockets using a very accurate custom mechanical digitizer. Results showed that quality varied considerably among the different manufacturers. Four of the companies consistently made sockets within +/−1.1% volume (approximately 1 sock ply) of the AAOP electronic shape file, while six other companies did not. Six of the companies showed consistent undersizing or oversizing in their sockets, which suggests a consistent calibration or manufacturing error. Other companies showed inconsistent sizing or shape distortion, a difficult problem that represents a most challenging limitation for central fabrication facilities. PMID:18247236
Clinical and histologic outcomes of calcium sulfate in the treatment of postextraction sockets.
Ruga, Emanuele; Gallesio, Cesare; Chiusa, Luigi; Boffano, Paolo
2011-03-01
The aim of this prospective study was to assess the clinical and histologic outcomes obtained with calcium sulfate (CS) used as a filler material in fresh premolar and molar postextraction sockets. Sixty premolar or molar postextraction sockets were filled with CS. Among the 60 grafted sockets, after 3 months, 50 underwent implant placement and clinical assessment. The removal of a sample core of newly generated intrasocket tissue was performed in 19 sockets. Collected samples were sent for histologic examination. The percentage of vital bone, nonvital bone, residual CS, amorphous material, and connective areas in every sample was calculated and recorded. Fifty postextraction regenerated sockets that underwent implant placement 3 months after tooth removal were included in this study.A partial postoperative exposition of the graft was observed in 12 of 50 sockets. At the surgical reentry, the augmented extraction sockets were completely filled by a hard material with an adequate alveolar crest in 41 cases. Histologic examination of the cores revealed that 63.16% of the intrasocket tissue was new vital bone, 2.1% was nonvital bone, 4.74% was fibrous tissue, and 30% was amorphous material. No residual CS was identified in bone cores. This study confirmed that CS is an ideal grafting material. The clinical adequacy aspect of filled sockets at surgical reentry seemed to be indicative of a qualitatively better bone regeneration. Postoperative exposition of graft material after a first intervention seemed to constitute an important risk factor for a worse bone regeneration.
NASA Technical Reports Server (NTRS)
Green, Chris; Greenwell, Chris; Brusse, jay; Krus, Dennis; Leidecker, Henning
2009-01-01
During system level testing intermittent and permanent open circuit failures of mated, crimp removable, electrical contact pairs were experienced. The root cause of the failures was determined to be low (but not zero) contact forces applied by the socket contact tines against the engaging pin. The low contact force reduces the effectiveness of the wiping action of the socket tines against the pin. The observed failure mode may be produced when insufficient wiping during mate, demate and small relative movement in use allows for the accumulation of debris or insulating films that electrically separate the contact pair. The investigation identified at least three manufacturing process control problems associated with the socket contacts that enabled shipment of contacts susceptible to developing low contact forces: (1) Improper heat treatment of the socket tines resulting in plastic rather than elastic behavior; (2) Overly thinned socket tines at their base resulting in reduced pin retention forces; (3) insufficient screening tests to identify parts susceptible to the aforementioned failure mechanisms. The results from an extensive screening program of socket contacts utilizing the industry standard contact separation force test procedures are described herein. The investigation shows this method to be capable of identifying initially weak sockets. However, sockets whose contact retention forces may degrade during use may not be screened out by pin retention testing alone. Further investigations are required to correlate low contact retention forces with increased electrical contact resistance in the presence of insulating films that may accumulate in the use environment.
Kobayashi, Toshiki; Orendurff, Michael S; Zhang, Ming; Boone, David A
2014-05-01
The alignment of transtibial prostheses has a systematic effect on the mean socket reaction moments in amputees. However, understanding their individual differences in response to alignment perturbations is also important for prosthetists to fully utilize the socket reaction moments for dynamic alignment in each unique patient. The aim of this study was to investigate individual responses to alignment perturbations in transtibial prostheses with solid-ankle-cushion-heel feet. A custom instrumented prosthesis alignment component was used to measure the socket reaction moments while walking in 11 amputees with transtibial prostheses under 17 alignment conditions, including 3° and 6° of flexion, extension, abduction, and adduction of the socket, 5mm and 10mm of anterior, posterior, lateral, and medial translation of the socket, and an initial baseline alignment. Coronal moments at 30% of stance and maximum sagittal moments were extracted for comparisons from each amputee. In the coronal plane, varus moment at 30% of stance was generally reduced by adduction or medial translation of the socket in all the amputees. In the sagittal plane, extension moment was generally increased by posterior translation or flexion of the socket; however, this was not necessarily the case for all the amputees. Individual responses to alignment perturbations are not always consistent, and prosthetists would need to be aware of this variance when addressing individual socket reaction moments during dynamic alignment in clinical setting. Copyright © 2014 Elsevier Ltd. All rights reserved.
Histologic effects of intentional-socket-assisted orthodontic movement in rabbits.
Yu, Ji-Yeon; Lee, Won; Park, Jae Hyun; Bayome, Mohamed; Kim, Yong; Kook, Yoon-Ah
2012-08-01
This study aimed to evaluate the effect of an intentionally created socket on bone remodeling with orthodontic tooth movement in rabbits. Eighteen male rabbits weighing 3.8 - 4.25 kg were used. An 8-mm deep and 2-mm wide socket was drilled in the bone 1 mm mesial to the right mandibular first premolar. The left first premolar was extracted to serve as an extraction socket. A traction force of 100 cN was applied to the right first premolar and left second premolar. Sections were obtained at the middle third of the moving tooth for both the drilled and extraction sockets and evaluated with hematoxylin and eosin staining and immunohistochemical analyses. The amount of tooth movement and tartrate-resistant acid phosphatase (TRAP)-positive cell count were compared between the 2 groups using the Mann-Whitney U test. At week 2, the distance of tooth movement was significantly higher in the intentional socket group (p < 0.05) than in the extraction socket group. The number of TRAP-positive cells decreased in week 2 but increased in week 3 (p < 0.05). However, there were no significant differences between the groups. Furthermore, results of transforming growth factor (TGF)-β staining revealed no significant differences. The intentional socket group showed greater distance of tooth movement than did the extraction socket group at week 2. Osteoclast counts and results of immunohistochemical analyses suggested elevated bone remodeling in both the groups. Thus, osteotomy may be an effective modality for enhancing tooth movement in orthodontic treatment.
Fickl, Stefan; Zuhr, Otto; Wachtel, Hannes; Kebschull, Moritz; Hürzeler, Markus B
2009-10-01
The aim of this study was to histometrically assess alterations of the ridge following socket preservation alone and socket preservation with additional buccal overbuilding. In five beagle dogs four extraction sites were randomly subjected to one of the following treatments: Tx 1: The socket was filled with BioOss Collagen and covered with a free gingival graft from the palate. Tx 2: The buccal bone plate was augmented using the GBR-technique, the socket was filled with BioOss Collagen and covered with a free gingival graft. Tx 3: The buccal bone plate was forced into a buccal direction using a manual bone spreader. The socket was filled with BioOss Collagen and covered with a free gingival graft from the palate. Tx 4: The socket was filled with BioOss Collagen and a combined free gingival/connective tissue graft was used to cover the socket and for buccal tissue augmentation. For each experimental site, two histological sections were subjected to histometric analysis and evaluated for (i) vertical bone dimensions and (ii) horizontal bone dimensions. All treatment groups showed horizontal and vertical bone loss. The mean vertical bone loss of the buccal bone plate was significantly lower in Tx 4 than in the other groups, while no statistical significant differences could be detected among the groups in the horizontal dimension. Overbuilding the buccal aspect in combination with socket preservation does not seem to be a suitable technique to compensate for the alterations after tooth extraction.
Implementation of Submerged Arc Welding Training. Final Report.
ERIC Educational Resources Information Center
Bowick, Earl; Todd, John
A unit on submerged arc welding (SAW) was developed and integrated into the welding program at Seattle Central Community College (Washington) during the period December 1983 through May 1984. During this time, 10 major users of SAW in the area were contacted and mailed questionnaires. Follow up consisted of telephone calls and personal contact as…
2014-10-01
Award Number: W81XWH-10-1-0744 TITLE: Development of Subischial Prosthetic Sockets with Vacuum...REPORT TYPE Annual 3. DATES COVERED 15 Sep 2013 – 14 Sep 2014 4. TITLE AND SUBTITLE Development of Subischial Prosthetic Sockets with Vacuum...to develop a highly flexible sub-ischial prosthetic socket with assisted-vacuum suspension for highly active persons with transfemoral amputation. The
Tang, Jinghua; McGrath, Michael; Laszczak, Piotr; Jiang, Liudi; Bader, Dan L; Moser, David; Zahedi, Saeed
2015-12-01
Design and fitting of artificial limbs to lower limb amputees are largely based on the subjective judgement of the prosthetist. Understanding the science of three-dimensional (3D) dynamic coupling at the residuum/socket interface could potentially aid the design and fitting of the socket. A new method has been developed to characterise the 3D dynamic coupling at the residuum/socket interface using 3D motion capture based on a single case study of a trans-femoral amputee. The new model incorporated a Virtual Residuum Segment (VRS) and a Socket Segment (SS) which combined to form the residuum/socket interface. Angular and axial couplings between the two segments were subsequently determined. Results indicated a non-rigid angular coupling in excess of 10° in the quasi-sagittal plane and an axial coupling of between 21 and 35 mm. The corresponding angular couplings of less than 4° and 2° were estimated in the quasi-coronal and quasi-transverse plane, respectively. We propose that the combined experimental and analytical approach adopted in this case study could aid the iterative socket fitting process and could potentially lead to a new socket design. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.
Safari, Mohammad Reza; Meier, Margrit Regula
2015-01-01
This review is an attempt to untangle the complexity of transtibial prosthetic socket fit and perhaps find some indication of whether a particular prosthetic socket type might be best for a given situation. In addition, we identified knowledge gaps, thus providing direction for possible future research. We followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, using medical subject headings and standard key words to search for articles in relevant databases. No restrictions were made on study design and type of outcome measure used. From the obtained search results (n = 1,863), 35 articles were included. The relevant data were entered into a predefined data form that included the Downs and Black risk of bias assessment checklist. This article presents the results from the systematic review of the quantitative outcomes (n = 27 articles). Trends indicate that vacuum-assisted suction sockets improve gait symmetry, volume control, and residual limb health more than other socket designs. Hydrostatic sockets seem to create less inconsistent socket fittings, reducing a problem that greatly influences outcome measures. Knowledge gaps exist in the understanding of clinically meaningful changes in socket fit and its effect on biomechanical outcomes. Further, safe and comfortable pressure thresholds under various conditions should be determined through a systematic approach.
NASA Technical Reports Server (NTRS)
Powell, Bradley W.; Burroughs, Ivan A.
1994-01-01
Through the two phases of this contract, sensors for welding applications and parameter extraction algorithms have been developed. These sensors form the foundation of a weld control system which can provide action weld control through the monitoring of the weld pool and keyhole in a VPPA welding process. Systems of this type offer the potential of quality enhancement and cost reduction (minimization of rework on faulty welds) for high-integrity welding applications. Sensors for preweld and postweld inspection, weld pool monitoring, keyhole/weld wire entry monitoring, and seam tracking were developed. Algorithms for signal extraction were also developed and analyzed to determine their application to an adaptive weld control system. The following sections discuss findings for each of the three sensors developed under this contract: (1) weld profiling sensor; (2) weld pool sensor; and (3) stereo seam tracker/keyhole imaging sensor. Hardened versions of these sensors were designed and built under this contract. A control system, described later, was developed on a multiprocessing/multitasking operating system for maximum power and flexibility. Documentation for sensor mechanical and electrical design is also included as appendices in this report.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schmitz, Roger William; Oh, Yunje
A heating assembly configured for use in mechanical testing at a scale of microns or less. The heating assembly includes a probe tip assembly configured for coupling with a transducer of the mechanical testing system. The probe tip assembly includes a probe tip heater system having a heating element, a probe tip coupled with the probe tip heater system, and a heater socket assembly. The heater socket assembly, in one example, includes a yoke and a heater interface that form a socket within the heater socket assembly. The probe tip heater system, coupled with the probe tip, is slidably receivedmore » and clamped within the socket.« less
High-Powered, Ultrasonically Assisted Thermal Stir Welding
NASA Technical Reports Server (NTRS)
Ding, Robert
2013-01-01
This method is a solid-state weld process capable of joining metallic alloys without melting. The weld workpieces to be joined by thermal stir welding (TSW) are drawn, by heavy forces, between containment plates past the TSW stir tool that then causes joining of the weld workpiece. TSW is similar to friction stir welding (FSW) in that material is heated into a plastic state (not melted) and stirred using a stir rod. The FSW pin tool is an integrated geometrical structure consisting of a large-diameter shoulder, and a smaller-diameter stir pin protruding from the shoulder. When the pin is plunged into a weld workpiece, the shoulder spins on the surface of the weld workpiece, thus inducing frictional heat into the part. The pin stirs the fraying surfaces of the weld joint, thus joining the weld workpiece into one structure. The shoulder and stir pin of the FSW pin tool must rotate together at a desired rotational speed. The induced frictional energy control and stir pin control of the pin tool cannot be de-coupled. The two work as one integrated unit. TSW, on the other hand, de-couples the heating and stirring of FSW, and allows for independent control of each process element. A uniquely designed induction coil heats the weld workpiece to a desired temperature, and once heated, the part moves into a stir rod whose RPM is also independently controlled. As the weld workpiece moves into the stir rod, the piece is positioned, or sandwiched, between upper and lower containment plates. The plate squeezes together, thus compressing the upper and lower surfaces of the weld workpiece. This compressive force, also called consolidation force, consolidates the plastic material within the weld nugget material as it is being stirred by the stir rod. The stir rod is positioned through the center of the top containment plate and protrudes midway through the opposite lower containment plate where it is mechanically captured. The upper and lower containment plates are separated by a distance equal to the thickness of the material being welded. The TSW process can be significantly improved by reducing the draw forces. This can be achieved by reducing the friction forces between the weld workpieces and the containment plates. High-power ultrasonic (HPU) vibrations of the containment plates achieve friction reduction in the TSW process. Furthermore, integration of the HPU energy into the TSW stir rod can increase tool life of the stir rod, and can reduce shear forces to which the stir rod is subjected during the welding process. TSW has been used to successfully join 0.500-in (˜13-mm) thick commercially pure (CP) titanium, titanium 6AL- 4V, and titanium 6AL-4V ELI in weld joint lengths up to 9 ft (˜2.75-m) long. In addition, the TSW process was used to fabricate a sub-scale hexagonally shaped gun turret component for the U.S. Navy. The turret is comprised of six 0.5000-in (˜13-mm) thick angled welds. Each angled weld joint was prepared by machining the mating surfaces to 120deg. The angled weld joint was then fixtured using an upper and lower containment plate of the same geometry of the angled weld joint. The weld joint was then stirred by the stir rod as it and the upper and lower containment plates traverse through the angled joint prep.
Kuroshima, Shinichiro; Al-Salihi, Zeina; Yamashita, Junro
2013-02-01
The quality and quantity of bone formed in tooth extraction sockets impact implant therapy. Therefore, the establishment of a new approach to enhance bone formation and to minimize bone resorption is important for the success of implant therapy. In this study, we investigated whether intermittent parathyroid hormone (PTH) therapy enhanced bone formation in grafted sockets. Tooth extractions of the maxillary first molars were performed in rats, and the sockets were grafted with xenograft. Intermittent PTH was administered either for 7 days before extractions, for 14 days after extractions, or both. The effect of PTH therapy on bone formation in the grafted sockets was assessed using microcomputed tomography at 14 days after extractions. PTH therapy for 7 days before extractions was not effective to augment bone fill, whereas PTH therapy for 14 days after operation significantly augmented bone formation in the grafted sockets. Intermittent PTH therapy starting right after tooth extractions significantly enhanced bone fill in the grafted sockets, suggesting that PTH therapy can be a strong asset for the success of the ridge preservation procedure.
Instrumented socket inserts for sensing interaction at the limb-socket interface.
Swanson, Eric C; McLean, Jake B; Allyn, Katheryn J; Redd, Christian B; Sanders, Joan E
2018-01-01
The objective of this research was to investigate a strategy for designing and fabricating computer-manufactured socket inserts that were embedded with sensors for field monitoring of limb-socket interactions of prosthetic users. An instrumented insert was fabricated for a single trans-tibial prosthesis user that contained three sensor types (proximity sensor, force sensing resistor, and inductive sensor), and the system was evaluated through a sequence of laboratory clinical tests and two days of field use. During in-lab tests 3 proximity sensors accurately distinguish between don and doff states; 3 of 4 force sensing resistors measured gradual pressure increases as weight-bearing increased; and the inductive sensor indicated that as prosthetic socks were added the limb moved farther out of the socket and pistoning amplitude decreased. Multiple sensor types were necessary in analysis of field collected data to interpret how sock changes affected limb-socket interactions. Instrumented socket inserts, with sensors selected to match clinical questions of interest, have the potential to provide important insights to improve patient care. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.
Advanced computer architecture specification for automated weld systems
NASA Technical Reports Server (NTRS)
Katsinis, Constantine
1994-01-01
This report describes the requirements for an advanced automated weld system and the associated computer architecture, and defines the overall system specification from a broad perspective. According to the requirements of welding procedures as they relate to an integrated multiaxis motion control and sensor architecture, the computer system requirements are developed based on a proven multiple-processor architecture with an expandable, distributed-memory, single global bus architecture, containing individual processors which are assigned to specific tasks that support sensor or control processes. The specified architecture is sufficiently flexible to integrate previously developed equipment, be upgradable and allow on-site modifications.
Osaki, Kanji; Okazaki, Ken; Matsubara, Hirokazu; Kuwashima, Umito; Murakami, Koji; Iwamoto, Yukihide
2015-12-01
To investigate the mismatch between the length at the center and the length on the shortest and longest peripheral sides of the femoral tunnel socket, reamed with the transportal (TP), outside-in (OI), and modified transtibial (TT) techniques, in anterior cruciate ligament (ACL) reconstruction. Femoral tunnel drilling was simulated on 3-dimensional bone models from 40 subjects. The tunnel directions used with the TP, OI, and modified TT techniques were previously described. By use of the resulting angle, a femoral tunnel socket of 9 mm in diameter was drilled from the center of the femoral ACL insertion. The virtual femoral tunnel was extracted, and the length mismatch was measured between the center and the shortest and longest peripheral sides of the tunnel socket. The mean socket length mismatch between the center and the shortest peripheral part of the femoral tunnel socket was 4.2 ± 0.9 mm with the TP technique, 5.2 ± 1.3 mm with the OI technique, and 3.2 ± 0.8 mm with the modified TT technique. The mean socket length mismatch between the center and the longest peripheral part of the femoral tunnel socket was 3.5 ± 0.9 mm with the TP technique, 4.8 ± 1.5 mm with the OI technique, and 3.3 ± 1.2 mm with the modified TT technique. The length mismatch was significantly higher when the tunnel socket was created by the OI technique (P < .01). A length mismatch with the tunnel socket exists after reaming with either the TP, OI, or modified TT technique. In particular, there was a significant increase in length mismatch when the tunnel socket was created by the OI technique, and the length mismatch would easily become greater than 5 mm. The surgeon should recognize this mismatch when it is created and measure the femoral tunnel socket. In anatomic ACL reconstruction, a mismatch between the length at the center and the length at periphery of the femoral tunnel socket occurs, and this is increased particularly when using the OI technique. The discrepancy in tunnel length between its center and its periphery could cause an overestimation of the tunnel length that could result in an error in length during graft preparation. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.
Kim, Jung-Ju; Song, Hyun Young; Ben Amara, Heithem; Kyung-Rim, Kang; Koo, Ki-Tae
2016-07-01
Previous studies on ridge preservation focusing on fresh extraction sockets using graft materials for ridge preservation procedures have reported a delay in the tissue modeling and remodeling phases. The objective of this study is to evaluate the effect of hyaluronic acid (HA) on healing of infected sockets. Six beagle dogs were used in this study. Both mandibular third premolars were hemisected, and the distal roots were extracted. Subsequently, periodontal and endodontic lesions were induced at the remaining mesial root. After communication of the periodontal lesion, an endodontic periapical lesion was observed at 4 months, and the mesial roots of both the right and left sides were extracted. HA was applied into the socket of the test group, and no treatment was administered to the other group (control group). Three months after extraction of the mesial roots, the dogs were sacrificed, and histologic evaluations were performed. The sockets were filled by mineralized bone (47.80% ± 6.60%) and bone marrow (50.47% ± 6.38%) in the control group, whereas corresponding values were 63.29% ± 9.78% and 34.73% ± 8.97% for the test group, respectively. There was a statistically significant difference between the groups. Reversal lines and a copious lineup of osteoblasts were observed in the middle and apical parts of the sockets in the test group. An infected socket shows delayed healing of the socket wound, and HA, because of its osteoinductive, bacteriostatic, and anti-inflammatory properties, may improve bone formation and accelerate wound healing in infected sockets.
Nasser, Qasiem J.; Gombos, Dan S.; Williams, Michelle D.; Guadagnolo, B. Ashleigh; Morrison, William H.; Garden, Adam S.; Beadle, Beth M.; Canseco, Elvia; Esmaeli, Bita
2012-01-01
Purpose High-dose radiotherapy can cause contracture of the anophthalmic socket, but the incidence of this complication in patients with enucleation for uveal melanoma has not previously been reported. We reviewed the surgical management and outcomes in terms of successful prosthesis wear in patients with severe contracture of the anophthalmic socket treated with high-dose radiotherapy for high-risk uveal melanoma and estimated the relative risk of this complication. Methods The medical records of all consecutive patients enrolled in a prospective uveal-melanoma tissue-banking protocol at our institution who underwent enucleation between January 2003 and December 2010 were reviewed. Patients who underwent adjuvant radiotherapy of the enucleated socket were further studied. Results Of the 68 patients enrolled in the prospective tissue banking protocol, 12 had high-risk histologic features (e.g., extrascleral spread or vortex vein invasion) and were treated with 60 Gy of external-beam radiotherapy after enucleation. Five of these patients (41.7%) experienced severe socket contracture precluding prosthesis wear. The median time to onset of contracture following completion of radiotherapy was 20 months. Three patients underwent surgery, which entailed scar tissue release, oral mucous membrane grafting, and socket reconstruction; 2 patients declined surgery. All 3 patients who had surgery experienced significant improvement of socket contracture that enabled patients to wear a prosthesis again. Conclusion High-dose radiotherapy after enucleation in patients with uveal melanoma caused severe socket contracture and inability to wear a prosthesis in approximately 40% of patients. Surgical repair of the contracted socket using oral mucous membrane grafting can allow resumption of prosthesis wear. PMID:22581085
Prosthetic limb sockets from plant-based composite materials.
Campbell, Andrew I; Sexton, Sandra; Schaschke, Carl J; Kinsman, Harry; McLaughlin, Brian; Boyle, Martin
2012-06-01
There is a considerable demand for lower limb prostheses globally due to vascular disease, war, conflict, land mines and natural disasters. Conventional composite materials used for prosthetic limb sockets include acrylic resins, glass and carbon fibres, which produce harmful gasses and dust in their manufacture. To investigate the feasibility of using a renewable plant oil-based polycarbonate-polyurethane copolymer resin and plant fibre composite, instead of conventional materials, to improve safety and accessibility of prosthetic limb manufacture. Experimental, bench research. Test pieces of the resin with a range of plant fibres (10.0% by volume) were prepared and tensile strengths were tested. Test sockets of both conventional composite materials and plant resin with plant fibres were constructed and tested to destruction. Combinations of plant resin and either banana or ramie fibres gave high tensile strengths. The conventional composite material socket and plant resin with ramie composite socket failed at a similar loading, exceeding the ISO 10328 standard. Both wall thickness and fibre-matrix adhesion played a significant role in socket strength. From this limited study we conclude that the plant resin and ramie fibre composite socket has the potential to replace the standard layup. Further mechanical and biocompatibility testing as well as a full economic analysis is required. Using readily sourced and renewable natural fibres and a low-volatile bio-resin has potential to reduce harm to those involved in the manufacture of artificial limb sockets, without compromising socket strength and benefitting clinicians working in poorer countries where safety equipment is scarce. Such composite materials will reduce environmental impact.
Sensing the gas metal arc welding process
NASA Technical Reports Server (NTRS)
Carlson, N. M.; Johnson, J. A.; Smartt, H. B.; Watkins, A. D.; Larsen, E. D.; Taylor, P. L.; Waddoups, M. A.
1994-01-01
Control of gas metal arc welding (GMAW) requires real-time sensing of the process. Three sensing techniques for GMAW are being developed at the Idaho National Engineering Laboratory (INEL). These are (1) noncontacting ultrasonic sensing using a laser/EMAT (electromagnetic acoustic transducer) to detect defects in the solidified weld on a pass-by-pass basis, (2) integrated optical sensing using a CCD camera and a laser stripe to obtain cooling rate and weld bead geometry information, and (3) monitoring fluctuations in digitized welding voltage data to detect the mode of metal droplet transfer and assure that the desired mass input is achieved.
Sensing the gas metal arc welding process
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carlson, N.M.; Johnson, J.A.; Smartt, H.B.
1992-01-01
Control of gas metal arc welding (GMAW) requires real-time sensing of the process. Three sensing techniques for GMAW are being developed at the Idaho National Engineering Laboratory (INEL). These are (1) noncontacting ultrasonic sensing using a laser/EMAT (electromagnetic acoustic transducer) to detect defects in the solidified weld on a pass-bypass basis, (2) integrated optical sensing using a CCD camera and a laser stripe to obtain cooling rate and weld bead geometry information, and (3) monitoring fluctuations in digitized welding voltage data to detect the mode of metal droplet transfer and assure that the desired mass input is achieved.
Sensing the gas metal arc welding process
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carlson, N.M.; Johnson, J.A.; Smartt, H.B.
1992-10-01
Control of gas metal arc welding (GMAW) requires real-time sensing of the process. Three sensing techniques for GMAW are being developed at the Idaho National Engineering Laboratory (INEL). These are (1) noncontacting ultrasonic sensing using a laser/EMAT (electromagnetic acoustic transducer) to detect defects in the solidified weld on a pass-bypass basis, (2) integrated optical sensing using a CCD camera and a laser stripe to obtain cooling rate and weld bead geometry information, and (3) monitoring fluctuations in digitized welding voltage data to detect the mode of metal droplet transfer and assure that the desired mass input is achieved.
Hattingh, André C; De Bruyn, Hugo; Ackermann, Andrew; Vandeweghe, Stefan
Immediate implant placement is performed less frequently in molar extraction sockets than in single root sockets. This is mainly due to the tripodal anatomical configuration of molar roots, which is perceived as complex and therefore unsuitable. The mechanical burden of molar sites, combined with much larger socket dimensions, make it amenable to the use of ultrawide-diameter dental implants. This article describes a practical, sequenced technique that can be used predictably for immediate implant placement in maxillary and mandibular first molar sockets, using a dry skull model for clarification. This detailed description is based on the experience of more than 580 clinical cases over a 10-year period.
Tolstunov, L
2012-12-01
The aim of this prospective comparative split-mouth study was to evaluate the role of socket irrigation with a normal saline solution routinely used at the end of extraction on the development of alveolar osteitis (AO) after removal of impacted mandibular third molars (MTMs). Thirty-five patients who satisfied the inclusion criteria were involved in the study and underwent extraction of four third-molars. To be included in the study, the mandibular third molars had to be impacted (partial or full bone) and require an osteotomy for extraction with use of a motorised drill. All surgeries were done under local anaesthesia or IV sedation. This was a prospective split-mouth study. The patient's left (assistant) side was a control side; it had a standard extraction technique of an impacted mandibular third molar that required a buccal full-thickness flap, buccal trough (osteotomy) and extraction of the tooth (with or without splitting the tooth into segments), followed by a traditional end-of-surgery debridement protocol consisting of a gentle curettage, bone filing of the socket walls, socket irrigation with approximately 5 ml of sterile normal saline solution and socket suctioning. The patient's right (operator) side was an experimental side; it also had a standard extraction technique of an impacted mandibular third molar at the beginning with a flap and osteotomy, but it was followed by a modified end-of-surgery protocol. It consisted of gentle curettage but the socket was not irrigated and not suctioned. It was simply left to bleed. The gauze was placed on top of the socket for haemostasis on both sides and the patient was asked to bite. On both sides, the buccal flap was positioned back without the suture. All patients were seen for a follow-up appointment four to seven days after the surgery to assess healing and check for symptoms and signs of alveolar osteitis, if present, on both irrigated and non-irrigated sides. This study followed the ethical guidelines of human subjects based on the Helsinki Declaration. Thirty-five patients or 70 sockets were evaluated. Eleven out of 35 patients in the study were subjected to a dry socket syndrome (31.4%). The higher number of AO was likely related to specifics of MTM selection in this study - only impacted (partial and full bone) MTMs were chosen. Among eleven patients with AO, two patients had a bilateral condition. By excluding two patients with bilateral dry sockets from the study, there were nine patients (18 extraction sites) with unilateral AO in the study. Seven out of nine patients (14 extraction sites) developed unilateral dry socket on the control (irrigated) side (77.8%) and only two (four extraction sites) on the experimental (non-irrigated) side (22.2%). Therefore, in this study there were 3.5 times more patients (extraction sites) with dry socket syndrome on the irrigated (control) side than patients (extraction sites) in the non-irrigated (experimental) side. A noticeable difference of dry socket syndromes (77.8% on the irrigated versus 22.2% on non-irrigated side) was demonstrated between the traditional extraction protocol versus modified approach without the end-of-surgery irrigation. The study demonstrated that the post-extraction socket bleeding is very important for the proper uncomplicated socket healing. If it's not washed away with irrigation solution at the end of extraction, the normal blood clot has a higher likelihood to form, and therefore, can potentially lead to an uncomplicated socket healing without development of alveolar osteitis. Socket bleeding at the extraction site creates a favourable environment for the formation of a blood clot - a protective dressing - necessary for a favourable osseous healing of the socket.
Antetomaso, Jordan; Kumar, Satish
2018-03-01
Immediate implant placement into fresh extraction sockets versus delayed implants into healed sockets: a systematic review and meta-analysis. Mello CC, Lemos CAA, Verri FR, Dos Santos DM, Goiato MC, Pellizzer EP. Int J Oral Maxillofac Surg 2017; 46(9):1162-77. None TYPE OF STUDY/DESIGN: Systematic review with meta-analysis of data. Copyright © 2017 Elsevier Inc. All rights reserved.
2016-10-01
laminated rigid frame to reduce thermal layers, increase flexibility and comfort while retaining ischial containment. In contrast, a Sub-I design has...design is comprised of a flexible interface and minimal laminated rigid frame to reduce thermal layers, increase flexibility and comfort while...AWARD NUMBER: W81XWH-15-1-0410 TITLE: The Effect of Prosthetic Socket Interface Design on Socket Comfort , Residual Limb Health, and Function
Nayak, Chitresh; Singh, Amit; Chaudhary, Himanshu; Unune, Deepak Rajendra
2017-10-23
Technological advances in prosthetics have attracted the curiosity of researchers in monitoring design and developments of the sockets to sustain maximum pressure without any soft tissue damage, skin breakdown, and painful sores. Numerous studies have been reported in the area of pressure measurement at the limb/socket interface, though, the relation between amputee's physiological parameters and the pressure developed at the limb/socket interface is still not studied. Therefore, the purpose of this work is to investigate the effects of patient-specific physiological parameters viz. height, weight, and stump length on the pressure development at the transtibial prosthetic limb/socket interface. Initially, the pressure values at the limb/socket interface were clinically measured during stance and walking conditions for different patients using strain gauges placed at critical locations of the stump. The measured maximum pressure data related to patient's physiological parameters was used to develop an artificial neural network (ANN) model. The effects of physiological parameters on the pressure development at the limb/socket interface were examined using the ANN model. The analyzed results indicated that the weight and stump length significantly affects the maximum pressure values. The outcomes of this work could be an important platform for the design and development of patient-specific prosthetic socket which can endure the maximum pressure conditions at stance and ambulation conditions.
29 CFR 1926.1414 - Wire rope-selection and installation criteria.
Code of Federal Regulations, 2014 CFR
2014-07-01
... sockets must be attached to the unloaded dead end of the rope only, except that the use of devices specifically designed for dead-ending rope in a wedge socket is permitted. (g) Socketing must be done in the...
29 CFR 1926.1414 - Wire rope-selection and installation criteria.
Code of Federal Regulations, 2012 CFR
2012-07-01
... sockets must be attached to the unloaded dead end of the rope only, except that the use of devices specifically designed for dead-ending rope in a wedge socket is permitted. (g) Socketing must be done in the...
29 CFR 1926.1414 - Wire rope-selection and installation criteria.
Code of Federal Regulations, 2013 CFR
2013-07-01
... sockets must be attached to the unloaded dead end of the rope only, except that the use of devices specifically designed for dead-ending rope in a wedge socket is permitted. (g) Socketing must be done in the...
NASA Astrophysics Data System (ADS)
Ma, Hang; Wang, Ying; Qin, Qing-Hua
2011-04-01
Based on the concept of eigenstrain, a straightforward computational model of the inverse approach is proposed for determining the residual stress field induced by welding using the eigenstrain formulations of boundary integral equations. The eigenstrains are approximately expressed in terms of low-order polynomials in the local area around welded zones. The domain integrals with polynomial eigenstrains are transformed into the boundary integrals to preserve the favourable features of the boundary-only discretization in the process of numerical solutions. The sensitivity matrices in the inverse approach for evaluating the eigenstrain fields are constructed by either the measured deformations (displacements) on the boundary or the measured stresses in the domain after welding over a number of selected measuring points, or by both the measured information. It shows from the numerical examples that the results of residual stresses from deformation measurements are always better than those from stress measurements but they are sensitive to the noises from experiments. The results from stress measurements can be improved by introducing a few deformation measuring points while reducing the number of points for stress measuring to reduce the cost since the measurement of deformation is easier than that of stresses in practice.
NASA Astrophysics Data System (ADS)
Dabos, G.; Pitris, S.; Mitsolidou, C.; Alexoudi, T.; Fitsios, D.; Cherchi, M.; Harjanne, M.; Aalto, T.; Kanellos, G. T.; Pleros, N.
2017-02-01
As data centers constantly expand, electronic switches are facing the challenge of enhanced scalability and the request for increased pin-count and bandwidth. Photonic technology and wavelength division multiplexing have always been a strong alternative for efficient routing and their potential was already proven in the telecoms. CWDM transceivers have emerged in the board-to-board level interconnection, revealing the potential for wavelength-routing to be applied in the datacom and an AWGR-based approach has recently been proposed towards building an optical multi-socket interconnection to offer any-to-any connectivity with high aggregated throughput and reduced power consumption. Echelle gratings have long been recognized as the multiplexing block exhibiting smallest footprint and robustness in a wide number of applications compared to other alternatives such as the Arrayed Waveguide Grating. Such filtering devices can also perform in a similar way to cyclical AWGR and serve as mid-board routing platforms in multi-socket environments. In this communication, we present such a 3x3 Echelle grating integrated on thick SOI platform with aluminum-coated facets that is shown to perform successful wavelength-routing functionality at 10 Gb/s. The device exhibits a footprint of 60x270 μm2, while the static characterization showed a 3 dB on-chip loss for the best channel. The 3 dB-bandwidth of the channels was 4.5 nm and the free spectral range was 90 nm. The echelle was evaluated in a 2x2 wavelength routing topology, exhibiting a power penalty of below 0.4 dB at 10-9 BER for the C-band. Further experimental evaluations of the platform involve commercially available CWDM datacenter transceivers, towards emulating an optically-interconnected multi-socket environment traffic scenario.
Hasheminia, Dariush; Moaddabi, Amirhossein; Moradi, Saeid; Soltani, Parisa; Moannaei, Mahsa; Issazadeh, Maryam
2018-05-01
Dry socket or alveolar osteitis is a delayed healing of alveolar bone after exodontia causing moderate to severe pain 2-4 days after extraction of teeth. Antibacterial agents such as antibiotics and chlorhexidine have been previously proved to prevent or reduce the incidence of dry socket. Betadine is a mixture of iodine and povidone which has bactericidal, antifungal and antiviral effects. The aim of the present study was to evaluate the effect of preoperative povidone iodine 1% mouthwash before surgical extraction of impacted mandibular third molar, however age, gender and oral hygiene were also considered. 189 patients who needed surgical extraction of Pell and Gregory class A and B mandibular third molars were included in this study. The patients who were not willing to participate in the study, took, women who took oral contraceptives or were in the first 22 days of menstrual cycle were excluded. Patients were randomly assigned to control or test group. 97 patients in the test group took preoperative povidone iodine 1% mouthwash and 92 patients in the control group didn't take any antibiotic or mouthwash. Patients were examined in days 3 and 7 postoperatively for incidence of alveolar osteitis. Chi-square test didn't show any significant relation between dry socket incidence and gender ( p value: 0.848) and Oral hygiene ( p value: 0.866). However, it revealed a significant relation between age and dry socket incidence ( p value: 0.003) and patients older than 30 were reported to have higher incidence of dry socket. Independent T-Test showed a significant difference between the test and control group in incidence of dry socket ( p value: 0.036). Based on the results of this study povidone iodine 1% mouthwash can decrease dry socket incidence also as the age increases, the incidence of dry socket becomes higher. Key words: Dry socket, impaction, betadine, povidone iodine.
Hasheminia, Dariush; Moaddabi, Amirhossein; Moradi, Saeid; Moannaei, Mahsa; Issazadeh, Maryam
2018-01-01
Background Dry socket or alveolar osteitis is a delayed healing of alveolar bone after exodontia causing moderate to severe pain 2-4 days after extraction of teeth. Antibacterial agents such as antibiotics and chlorhexidine have been previously proved to prevent or reduce the incidence of dry socket. Betadine is a mixture of iodine and povidone which has bactericidal, antifungal and antiviral effects. The aim of the present study was to evaluate the effect of preoperative povidone iodine 1% mouthwash before surgical extraction of impacted mandibular third molar, however age, gender and oral hygiene were also considered. Material and Methods 189 patients who needed surgical extraction of Pell and Gregory class A and B mandibular third molars were included in this study. The patients who were not willing to participate in the study, took, women who took oral contraceptives or were in the first 22 days of menstrual cycle were excluded. Patients were randomly assigned to control or test group. 97 patients in the test group took preoperative povidone iodine 1% mouthwash and 92 patients in the control group didn’t take any antibiotic or mouthwash. Patients were examined in days 3 and 7 postoperatively for incidence of alveolar osteitis. Results Chi-square test didn’t show any significant relation between dry socket incidence and gender (p value: 0.848) and Oral hygiene (p value: 0.866). However, it revealed a significant relation between age and dry socket incidence (p value: 0.003) and patients older than 30 were reported to have higher incidence of dry socket. Independent T-Test showed a significant difference between the test and control group in incidence of dry socket (p value: 0.036). Conclusions Based on the results of this study povidone iodine 1% mouthwash can decrease dry socket incidence also as the age increases, the incidence of dry socket becomes higher. Key words:Dry socket, impaction, betadine, povidone iodine. PMID:29849968
Systemic review of dry socket: aetiology, treatment, and prevention.
Tarakji, Bassel; Saleh, Lubna Ahmed; Umair, Ayesha; Azzeghaiby, Saleh Nasser; Hanouneh, Salah
2015-04-01
Our systemic review is to make a comprehensive review about the aetiology, treatment and the prevention of dry socket, the inclusion criteria were all the studies that discuss the dry socket and its etiology, treatment and prevention and exclusion criteria were all the studies that discuss the other complications of tooth extraction, the materials and methods used for this systemic review was to search in the Pub Medline database between 2008 to 2013, using specific words "dry socket, aetiology, treatment and prevention" and published in the English language, the articles were screened by abstract for relevance to aetiology, treatment and prevention of dry socket, 82 papers were identified in pub med but a total of 36 out of Publications were included in the final systemic review according to the specific keywords and materials mentioned above. The occurrence of dry socket in an everyday oral surgery or dental practice is unavoidable. The risk factors are smoking, surgical trauma, single extractions, age, sex, medical history, systemic disorder, extraction site, amount of anaesthesia, operator experience, antibiotics use prior to surgery, difficulty of the surgery and the previous surgical site infection in addition to oral Contraceptives, menstrual cycle and immediate postextraction socket irrigation with normal saline. The traditional options of treatment are directed toward palliative care, such as the irrigation of the surgical site, avoiding curetting the extraction socket, Packing with a zinc oxide- eugenol paste on iodoform gauze can be considered to relieve acute pain episodes, there is also new agents in the market can accelerate the healing of the socket such as PRGF and GECB. The prevention methods include avoiding smoking before and after surgery and a traumatic surgery, the use of antibiotics, such as, azithromycin, can be considered, the other preventive measures such as chlorhecidine rinse or gel can be effective in the reduction of dry socket incidence.
Systemic Review of Dry Socket: Aetiology, Treatment, and Prevention
Saleh, Lubna Ahmed; Umair, Ayesha; Azzeghaiby, Saleh Nasser; Hanouneh, Salah
2015-01-01
Our systemic review is to make a comprehensive review about the aetiology, treatment and the prevention of dry socket, the inclusion criteria were all the studies that discuss the dry socket and its etiology, treatment and prevention and exclusion criteria were all the studies that discuss the other complications of tooth extraction, the materials and methods used for this systemic review was to search in the Pub Medline database between 2008 to 2013, using specific words “dry socket, aetiology, treatment and prevention” and published in the English language, the articles were screened by abstract for relevance to aetiology, treatment and prevention of dry socket, 82 papers were identified in pub med but a total of 36 out of Publications were included in the final systemic review according to the specific keywords and materials mentioned above. The occurrence of dry socket in an everyday oral surgery or dental practice is unavoidable. The risk factors are smoking, surgical trauma, single extractions, age, sex, medical history, systemic disorder, extraction site, amount of anaesthesia, operator experience, antibiotics use prior to surgery, difficulty of the surgery and the previous surgical site infection in addition to oral Contraceptives, menstrual cycle and immediate postextraction socket irrigation with normal saline. The traditional options of treatment are directed toward palliative care, such as the irrigation of the surgical site, avoiding curetting the extraction socket, Packing with a zinc oxide– eugenol paste on iodoform gauze can be considered to relieve acute pain episodes, there is also new agents in the market can accelerate the healing of the socket such as PRGF and GECB. The prevention methods include avoiding smoking before and after surgery and a traumatic surgery, the use of antibiotics, such as, azithromycin, can be considered, the other preventive measures such as chlorhecidine rinse or gel can be effective in the reduction of dry socket incidence. PMID:26023661
An assessment technique for computer-socket manufacturing
Sanders, Joan; Severance, Michael
2015-01-01
An assessment strategy is presented for testing the quality of carving and forming of individual computer aided manufacturing facilities. The strategy is potentially useful to facilities making sockets and companies marketing manufacturing equipment. To execute the strategy, an evaluator fabricates a collection of test models and sockets using the manufacturing suite under evaluation, and then measures their shapes using scanning equipment. Overall socket quality is assessed by comparing socket shapes with electronic file shapes. Then model shapes are compared with electronic file shapes to characterize carving performance. Socket shapes are compared with model shapes to characterize forming performance. The mean radial error (MRE), which is the average difference in radii between the two shapes being compared, provides insight into sizing quality. Inter-quartile range (IQR), the range of radial error for the best matched half of the points on the surfaces being compared, provides insight into shape quality. By determining MRE and IQR for carving and forming separately, the source(s) of socket shape error may be pinpointed. The developed strategy may provide a useful tool to the prosthetics community and industry to help identify problems and limitations in computer aided manufacturing and insight into appropriate modifications to overcome them. PMID:21938663
HOW DOES ADDING AND REMOVING LIQUID FROM SOCKET BLADDERS AFFECT RESIDUAL LIMB FLUID VOLUME?
Sanders, JE; Cagle, JC; Harrison, DS; Myers, TR; Allyn, KJ
2015-01-01
Adding and removing liquid from socket bladders is a means for people with limb loss to accommodate residual limb volume change. Nineteen people with trans-tibial amputation using their regular prosthetic socket fitted with fluid bladders on the inside socket surface underwent cycles of bladder liquid addition and removal. In each cycle, subjects sat, stood, and walked for 90s with bladder liquid added and then sat, stood, and walking for 90s again with the bladder liquid removed. The amount of bladder liquid added was increased in each cycle. Bioimpedance analysis was implemented to measure residual limb fluid volume. Results showed that the preferred bladder liquid volume was 16.8 mL (s.d.8.4), corresponding to 1.7% (s.d.0.8%) of the average socket volume between the bioimpedance voltage-sensing electrodes. Limb fluid volume driven out of the residual limb when bladder liquid was added was typically not recovered upon subsequent bladder liquid removal. Fifteen of nineteen subjects experienced a gradual limb fluid volume loss over the test session. Care should be taken when implementing adjustable socket technologies in people with limb amputation. Reducing socket volume may accentuate limb fluid volume loss. PMID:24203546
Biswas, Sondip K; Lee, Jai Eun; Brako, Lawrence; Jiang, Jean X; Lo, Woo-Kuen
2010-11-09
Ball-and-sockets and protrusions are specialized interlocking membrane domains between lens fibers of all species studied. Ball-and-sockets and protrusions are similar in their shape, size, and surface morphology, and are traditionally believed to play a key role in maintaining fiber-to-fiber stability. Here, we evaluate the hypothesis that ball-and-sockets and protrusions possess important structural and functional differences during fiber cell differentiation and maturation. Intact lenses of leghorn chickens (E7 days to P62 weeks old) and rhesus monkeys (1.5-20 years old) were studied with SEM, freeze-fracture TEM, freeze-fracture immunogold labeling (FRIL), and filipin cytochemistry for membrane cholesterol detection. SEM showed that ball-and-sockets were distributed along the long and short sides of hexagonal fiber cells, whereas protrusions were located along the cell corners, from superficial to deep cortical regions in both chicken and monkey lenses. Importantly, by freeze-fracture TEM, we discovered the selective association of gap junctions with all ball-and-sockets examined, but not with protrusions, in both species. In the embryonic chicken lens (E18), the abundant distribution of ball-and-socket gap junctions was regularly found in an approximate zone extending at least 300 μm deep from the equatorial surface of the superficial cortical fibers. Many ball-and-socket gap junctions often protruded deeply into neighboring cells. However, in the mature fibers of monkey lenses, several ball-and-sockets exhibited only partial occupancy of gap junctions with disorganized connexons, possibly due to degradation of gap junctions during fiber maturation and aging. FRIL analysis confirmed that both connexin46 (Cx46) and connexin50 (Cx50) antibodies specifically labeled ball-and-socket gap junctions, but not protrusions. Furthermore, filipin cytochemistry revealed that the ball-and-socket gap junctions contained different amounts of cholesterol (i.e., cholesterol-rich versus cholesterol-free) as seen with the filipin-cholesterol-complexes (FCC) in different cortical regions during maturation. In contrast, the protrusions contained consistently high cholesterol amounts (i.e., 402 FCCs/μm2 membrane) which were approximately two times greater than that of the cholesterol-rich gap junctions (i.e., 188 FCCs/μm2 membrane) found in ball-and-sockets. Gap junctions are regularly associated with all ball-and-sockets examined in metabolically active young cortical fibers, but not with protrusions, in both chicken and monkey lenses. Since these unique gap junctions often protrude deeply into neighboring cells to increase membrane surface areas, they may significantly facilitate cell-to-cell communication between young cortical fiber cells. In particular, the large number of ball-and-socket gap junctions found near the equatorial region may effectively facilitate the flow of outward current toward the equatorial surface for internal circulation of ions in the lens. In contrast, a consistent distribution of high concentrations of cholesterol in protrusions would make the protrusion membrane less deformable and would be more suitable for maintaining fiber-to-fiber stability during visual accommodation. Thus, the ball-and-sockets and protrusions are two structurally and functionally distinct membrane domains in the lens.
Biswas, Sondip K.; Lee, Jai Eun; Brako, Lawrence; Jiang, Jean X.
2010-01-01
Purpose Ball-and-sockets and protrusions are specialized interlocking membrane domains between lens fibers of all species studied. Ball-and-sockets and protrusions are similar in their shape, size, and surface morphology, and are traditionally believed to play a key role in maintaining fiber-to-fiber stability. Here, we evaluate the hypothesis that ball-and-sockets and protrusions possess important structural and functional differences during fiber cell differentiation and maturation. Methods Intact lenses of leghorn chickens (E7 days to P62 weeks old) and rhesus monkeys (1.5–20 years old) were studied with SEM, freeze-fracture TEM, freeze-fracture immunogold labeling (FRIL), and filipin cytochemistry for membrane cholesterol detection. Results SEM showed that ball-and-sockets were distributed along the long and short sides of hexagonal fiber cells, whereas protrusions were located along the cell corners, from superficial to deep cortical regions in both chicken and monkey lenses. Importantly, by freeze-fracture TEM, we discovered the selective association of gap junctions with all ball-and-sockets examined, but not with protrusions, in both species. In the embryonic chicken lens (E18), the abundant distribution of ball-and-socket gap junctions was regularly found in an approximate zone extending at least 300 μm deep from the equatorial surface of the superficial cortical fibers. Many ball-and-socket gap junctions often protruded deeply into neighboring cells. However, in the mature fibers of monkey lenses, several ball-and-sockets exhibited only partial occupancy of gap junctions with disorganized connexons, possibly due to degradation of gap junctions during fiber maturation and aging. FRIL analysis confirmed that both connexin46 (Cx46) and connexin50 (Cx50) antibodies specifically labeled ball-and-socket gap junctions, but not protrusions. Furthermore, filipin cytochemistry revealed that the ball-and-socket gap junctions contained different amounts of cholesterol (i.e., cholesterol-rich versus cholesterol-free) as seen with the filipin-cholesterol-complexes (FCC) in different cortical regions during maturation. In contrast, the protrusions contained consistently high cholesterol amounts (i.e., 402 FCCs/μm2 membrane) which were approximately two times greater than that of the cholesterol-rich gap junctions (i.e., 188 FCCs/μm2 membrane) found in ball-and-sockets. Conclusions Gap junctions are regularly associated with all ball-and-sockets examined in metabolically active young cortical fibers, but not with protrusions, in both chicken and monkey lenses. Since these unique gap junctions often protrude deeply into neighboring cells to increase membrane surface areas, they may significantly facilitate cell-to-cell communication between young cortical fiber cells. In particular, the large number of ball-and-socket gap junctions found near the equatorial region may effectively facilitate the flow of outward current toward the equatorial surface for internal circulation of ions in the lens. In contrast, a consistent distribution of high concentrations of cholesterol in protrusions would make the protrusion membrane less deformable and would be more suitable for maintaining fiber-to-fiber stability during visual accommodation. Thus, the ball-and-sockets and protrusions are two structurally and functionally distinct membrane domains in the lens. PMID:21139982
... end of the femur, which fits in a socket in the pelvis. Your hip is known as a ball-and-socket joint. This is because you have a ball ... of your femur, and it fits into a socket in your pelvis. This makes your hips very ...
Detachable connection for a nuclear reactor fuel assembly
Christiansen, D.W.; Karnesky, R.A.
1983-08-29
A locking connection for releasably attaching a handling socket to the duct tube of a fuel assembly for a nuclear reactor. The connection comprises a load pad housing mechanically attached to the duct tube and a handling socket threadably secured within the housing. A retaining ring is interposed between the housing and the handling socket and is formed with a projection and depression engagable within a cavity and groove of the housing and handling socket, respectively, to form a detachable interlocked connection assembly.
Detachable connection for a nuclear reactor fuel assembly
Christiansen, David W.; Karnesky, Richard A.
1986-01-01
A locking connection for releasably attaching a handling socket to the duct tube of a fuel assembly for a nuclear reactor. The connection comprises a load pad housing mechanically attached to the duct tube and a handling socket threadably secured within the housing. A retaining ring is interposed between the housing and the handling socket and is formed with a projection and depression engageable within a cavity and groove of the housing and handling socket, respectively, to form a detachable interlocked connection assembly.
NASA Astrophysics Data System (ADS)
Mathew, J.; Moat, R. J.; Paddea, S.; Francis, J. A.; Fitzpatrick, M. E.; Bouchard, P. J.
2017-12-01
Economic and safe management of nuclear plant components relies on accurate prediction of welding-induced residual stresses. In this study, the distribution of residual stress through the thickness of austenitic stainless steel welds has been measured using neutron diffraction and the contour method. The measured data are used to validate residual stress profiles predicted by an artificial neural network approach (ANN) as a function of welding heat input and geometry. Maximum tensile stresses with magnitude close to the yield strength of the material were observed near the weld cap in both axial and hoop direction of the welds. Significant scatter of more than 200 MPa was found within the residual stress measurements at the weld center line and are associated with the geometry and welding conditions of individual weld passes. The ANN prediction is developed in an attempt to effectively quantify this phenomenon of `innate scatter' and to learn the non-linear patterns in the weld residual stress profiles. Furthermore, the efficacy of the ANN method for defining through-thickness residual stress profiles in welds for application in structural integrity assessments is evaluated.
Effects of Sealing Run Welding with Defocused Laser Beam on the Quality of T-joint Fillet Weld
NASA Astrophysics Data System (ADS)
Unt, Anna; Poutiainen, Ilkka; Salminen, Antti
Fillet weld is the predominant weld type used for connecting different elements e.g. in shipbuilding, offshore and bridge structures. One of prevalent research questions is the structural integrity of the welded joint. Post weld improvement techniques are being actively researched, as high stress areas like an incomplete penetration on the root side or fluctuations in penetration depth cannot be avoided. Development of laser and laser-arc hybrid welding processes have greatly contributed to increase of production capacity and reduction of heat-induced distortions by producing single pass full penetration welds in thin- and medium thickness structural steel parts. Present study addresses the issue of how to improve the quality of the fillet welds by welding the sealing run on the root side with defocused laser beam. Welds having incomplete or excessive penetration were produced with several beam angles and laser beam spot sizes on surface. As a conclusion, significant decrease or even complete elimination of the seam irregularities, which act as the failure starting points during service, is achieved.
NASA Astrophysics Data System (ADS)
Penasa, Mauro; Colombo, Enrico; Giolfo, Mauro
1994-09-01
Due to the good performance shown by laser welded joints, to the quality and repeatability achievable by this welding technique and to its high process productivity, a feature inherent to the laser technology which, together with its high flexibility, allows different operations to be performed by a single source, consistent savings in a production line may be obtained. Therefore laser welding techniques may be of high relevance for industrial applications, provided that a sufficient attention is paid to avoiding a low utilization time to the operating laser source. The paper describes a feasibility study for the integration of a laser source as an automatic unit for circumferential butt welding of tubes in production lines of pipe coils, just before the cold bending station. Using a 6 kW CO2 source, thickness ranging from 3.5 to 11.2 mm in carbon, low alloyed Cr-Mo and austenitic stainless steels, have been successfully welded. Cr-Mo steels require on line preheating treatment, which however can be achieved by laser defocused passes just before welding. The results of the preliminary qualification performed on laser welded joints of the involved topologies of product (materials, diameters and thicknesses) are described together with technological tests required for approval: laser circumferential butt welding of tubes has proven to be effective, with satisfactory and repeatable results and good joint performances. An exhaustive comparison with current welding techniques (TIG, MIG) is then carried out, along with a detailed analysis of the potential advantages and benefits which may be expected by using the laser welding technique, as well as with a first estimation of the investments and running costs. Since laser productivity is saturated only at a rough 35% during the year, an accurate analysis of other possible applications and of a possible lay out of a laser working cell integrated in the factory production lines is performed. Usually little attention is given to this problem and this is one of the causes of uncertainty when investments in a laser are planned. In most cases a source is devoted to a single application, even if effective working time is really low due to laser fast processing. Therefore potential benefits are substantially reduced to a minimum amount of what can be expected by this flexible technology.
Peculiarities of metal welding process modelling for the Arctic
NASA Astrophysics Data System (ADS)
Lagunov, Alexey; Fofanov, Andrey; Losunov, Anton
2017-09-01
M etal being rather tough has been used in the Arctic for a long time. In severe weather conditions metal construction is subject to strong corrosion and erosion. These processes affect the welds particular strongly. Violation of weld integrity leads to the different industrial accidents. Therefore, the welding quality is given such a strong focus. M ost high-quality welding is obtained if welding zone is provided with gas what eliminates the influence of oxygen on the process. But in this case it is very difficult to find the right concentration, gas pressure, direction of the jet. Study of the welding process using video and photography is expensive, in terms of money and time. Mathematical modelling of welding process using the program FlowVision enables to solve this issue at less cost. It's essential that obtained results qualitatively conform to the experimental ones and can be used in real application.
Karakoç, Mehmet; Batmaz, İbrahim; Sariyildiz, Mustafa Akif; Yazmalar, Levent; Aydin, Abdülkadir; Em, Serda
2017-08-01
Patients with amputation need prosthesis to comfortably move around. One of the most important parts of a good prosthesis is the socket. Currently, the most commonly used method is the traditional socket manufacturing method, which involves manual work; however, computer-aided design/computer-aided manufacturing (CAD/CAM) is also being used in the recent years. The present study aimed to investigate the effects of sockets manufactured by traditional and CAD/CAM method on clinical characteristics and quality of life of patients with transtibial amputation. The study included 72 patients with transtibial amputation using prosthesis, 36 of whom had CAD/CAM prosthetic sockets (group 1) and 36 had traditional prosthetic sockets (group 2). Amputation reason, prosthesis lifetime, walking time and distance with prosthesis, pain-free walking time with prosthesis, production time of the prosthesis, and adaptation time to the prosthesis were questioned. Quality of life was assessed using the 36-item Short Form Health Survey questionnaire and the Trinity Amputation and Prosthesis Experience Scales. Walking time and distance and pain-free walking time with prosthesis were significantly better in group 1 than those in group 2. Furthermore, the prosthesis was applied in a significantly shorter time, and socket adaptation time was significantly shorter in group 1. Except emotional role limitation, all 36-item Short Form Healthy Survey questionnaire parameters were significantly better in group 1 than in group 2. Trinity Amputation and Prosthesis Experience Scales activity limitation scores of group 1 were lower, and Trinity Amputation and Prosthesis Experience Scales satisfaction with the prosthesis scores were higher than those in group 2. Our study demonstrated that the sockets manufactured by CAD/CAM methods yield better outcomes in quality of life of patients with transtibial amputation than the sockets manufactured by the traditional method.
The effect of cancer therapies on pediatric anophthalmic sockets.
Shildkrot, Yevgeniy; Kirzhner, Maria; Haik, Barrett G; Qaddoumi, Ibrahim; Rodriguez-Galindo, Carlos; Wilson, Matthew W
2011-12-01
To determine the impact of chemotherapy or external beam radiotherapy (EBRT) on pediatric anophthalmic sockets. A retrospective, nonrandomized, interventional cohort study. A total of 135 sockets of 133 children undergoing enucleation from late 1999 to early 2009 at the St. Jude Children's Research Hospital were included. A retrospective chart review of outcomes after enucleation in patients treated with systemic chemotherapy or orbital EBRT either before or after removal of the eye compared with patients who received no other treatment. Incidence of implant exposure, migration, extrusion, socket contracture, and pyogenic granuloma formation. Retinoblastoma was the primary diagnosis in 128 eyes (95%). Median follow-up was 3.6 years (range, 0.1-9.3 years). Event-free course was observed in 94 sockets (69.6%). Complications included implant exposure (n = 28, 20.7%), socket contracture (n = 16, 11.9%), pyogenic granuloma (n = 9, 6.7%), implant extrusion (n = 3, 2.2%), and migration (n = 2, 1.5%). Exposure resolved in 21 sockets (77.8%) and improved in 2 sockets (11.1%); 1 patient with exposure died. Use of prior, adjuvant, or subsequent chemotherapy increased the long-term risk of exposure (odds ratio [OR] = 3.7; 95% confidence interval [CI], 1.4-9.4), and contracture (OR could not be calculated, P<0.0001). External beam radiotherapy greatly increased the risk of contracture (OR 24.0; 95% CI, 6.9-82.8) and exposure (OR 2.89; 95% CI, 1.1-7.9). In this unique pediatric population with cancer, chemotherapy and EBRT had an additive effect, significantly increasing the incidence of exposure and socket contracture. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
The Effect of Cancer Therapies on Pediatric Anophthalmic Sockets
Shildkrot, Yevgeniy; Kirzhner, Maria; Haik, Barrett G.; Qaddoumi, Ibrahim; Rodriguez-Galindo, Carlos; Wilson, Matthew W.
2012-01-01
Purpose To determine the impact of chemotherapy or external beam radiotherapy (EBRT) on pediatric anophthalmic sockets. Design A retrospective, nonrandomized, interventional cohort study. Participants A total of 135 sockets of 133 children undergoing enucleation from late 1999 to early 2009 at the St. Jude Children’s Research Hospital were included. Methods A retrospective chart review of outcomes after enucleation in patients treated with systemic chemotherapy or orbital EBRT either before or after removal of the eye compared with patients who received no other treatment. Main Outcome Measures Incidence of implant exposure, migration, extrusion, socket contracture, and pyogenic granuloma formation. Results Retinoblastoma was the primary diagnosis in 128 eyes (95%). Median follow-up was 3.6 years (range, 0.1–9.3 years). Event-free course was observed in 94 sockets (69.6%). Complications included implant exposure (n = 28, 20.7%), socket contracture (n = 16, 11.9%), pyogenic granuloma (n = 9, 6.7%), implant extrusion (n = 3, 2.2%), and migration (n = 2, 1.5%). Exposure resolved in 21 sockets (77.8%) and improved in 2 sockets (11.1%); 1 patient with exposure died. Use of prior, adjuvant, or subsequent chemotherapy increased the long-term risk of exposure (odds ratio [OR] = 3.7; 95% confidence interval [CI], 1.4–9.4), and contracture (OR could not be calculated, P<0.0001). External beam radiotherapy greatly increased the risk of contracture (OR 24.0; 95% CI, 6.9–82.8) and exposure (OR 2.89; 95% CI, 1.1–7.9). Conclusions In this unique pediatric population with cancer, chemotherapy and EBRT had an additive effect, significantly increasing the incidence of exposure and socket contracture. PMID:21856015
Kurtul, Bengi Ece; Erdener, Ugur; Mocan, Mehmet Cem; Irkec, Murat; Orhan, Mehmet
2014-01-01
To investigate and compare the cytopathological and clinical effects of amniotic membrane transplantation (AMT) and oral mucosal membrane transplantation (OMMT) in socket contraction. Twelve patients who could not be fitted with ocular prosthesis due to socket contracture were included in this study. Seven patients underwent AMT and 5 patients underwent OMMT. Thirteen patients who had healthy sockets were included as control group. Depth of inferior fornix, degree of inflammation, extent of the socket contracture and socket volume were measured in the preoperative period and at sixth and twelfth weeks postoperatively. Impression cytology of conjunctival fornices and tear transforming growth factor beta-1 (TGFβ1) levels were determined. In the AMT group, socket volume and lower fornix depth values were significantly higher (P=0.030 and P=0.004 respectively) and inflammation levels and impression cytology stages (P=0.037 and P=0.022 respectively) were significantly lower in postoperative period compared to preoperative period. In the OMMT group, no statistical differences were found in terms of clinical parameters, inflammation levels and impression cytology stages of preoperative versus postoperative values. Preoperative tear TGFβ1 levels were higher in AMT and OMMT groups compared to the control group (25.5 ng/mL, 26.3 ng/mL and 21.7 ng/mL respectively). Decreased tear TGFβ1 levels were observed in both the AMT and OMMT groups postoperatively (median decrease value=2.1 ng/mL and 2.7 ng/mL respectively). AMT is associated with postoperative improvement in inferior fornix depth, socket volume, inflammation and impression cytology levels and may be a more proper alternative method than OMMT in the management of socket contracture.
Poulias, Evmenios; Greenwell, Henry; Hill, Margaret; Morton, Dean; Vidal, Ricardo; Shumway, Brian; Peterson, Thomas L
2013-11-01
Previous studies of ridge preservation showed a loss of ≈18% or 1.5 mm of crestal ridge width in spite of treatment. The primary aim of this randomized, controlled, masked clinical trial is to compare a socket graft to the same treatment plus a buccal overlay graft, both with a polylactide membrane, to determine if loss of ridge width can be prevented by use of an overlay graft. Twelve patients who served as positive controls received an intrasocket mineralized cancellous allograft (socket group), and 12 patients received the same socket graft procedure plus buccal overlay cancellous xenograft (overlay group). Horizontal ridge dimensions were measured with a digital caliper, and vertical ridge changes were measured from a stent. Before implant placement, at 4 months, a trephine core was obtained for histologic analysis. The mean horizontal ridge width at the crest for the socket group decreased from 8.7 ± 1.0 to 7.1 ± 1.5 mm for a mean loss of 1.6 ± 0.8 mm (P <0.05), whereas the same measurement for the overlay group decreased from 8.4 ± 1.4 to 8.1 ± 1.4 mm for a mean loss of 0.3 ± 0.9 mm (P >0.05). The overlay group was significantly different from the socket group (P <0.05). Histologic analysis revealed that the socket group had 35% ± 16% vital bone, and the overlay group had 40% ± 16% (P >0.05). The overlay treatment significantly prevented loss of ridge width and preserved or augmented the buccal contour. The socket and overlay groups healed with a high percentage of vital bone.
The modular socket system in a rural setting in Indonesia.
Giesberts, Bob; Ennion, Liezel; Hjelmstrom, Olle; Karma, Agusni; Lechler, Knut; Hekman, Edsko; Bergsma, Arjen
2018-06-01
Prosthetic services are inaccessible to people living in rural areas. Systems like the modular socket system have the potential to be fabricated outside of the prosthetic workshop. This study aimed to evaluate the patient's performance and satisfaction with the use of the modular socket system, and the technical feasibility of its implementation in a rural setting. A quantitative longitudinal descriptive study design was followed. A total of 15 persons with a lower limb amputation were fitted with the modular socket system and followed over 4-6 months. Performance was measured using a 2-min walk test, 10-m walk test and mobility and function questionnaire. Satisfaction was measured by the Socket Fit Comfort Score, Prosthesis Evaluation Questionnaire and EuroQoL 5 Dimensions 5 Levels. Notes on technical feasibility were taken at the moment of fitting ( t 0 ), at 1-3 months post fitting ( t 1 ) and at the end evaluation at 4-6 months post fitting ( t 2 ). Performance did not change between t 0 and t 2 . The comfort of the socket fit reduced between t 0 and t 2 . Satisfaction with prosthesis and general health status stayed constant over time. The average fitting-time for the modular socket system was 6.4 h. The modular socket system can be considered a useful alternative for use in rural settings. Clinical relevance The use of the modular socket system is feasible and can improve accessibility to prosthetic technology in rural areas. Experienced prosthetic users were satisfied with the performance and the device. The shorter manufacturing time and use of only hand-held tools makes it an ideal alternative for use in remote and rural settings.
Kobayashi, Toshiki; Orendurff, Michael S; Zhang, Ming; Boone, David A
2013-04-26
Alignment is important for comfortable and stable gait of lower-limb prosthesis users. The magnitude of socket reaction moments in the multiple planes acting simultaneously upon the residual limb may be related to perception of comfort in individuals using prostheses through socket interface pressures. The aim of this study was to investigate the effect of prosthetic alignment changes on sagittal and coronal socket reaction moment interactions (moment-moment curves) and to characterize the curves in 11 individuals with transtibial amputation using novel moment-moment interaction parameters measured by plotting sagittal socket reaction moments versus coronal ones under various alignment conditions. A custom instrumented prosthesis alignment component was used to measure socket reaction moments during walking. Prosthetic alignment was tuned to a nominally aligned condition by a prosthetist, and from this position, angular (3° and 6° of flexion, extension, abduction or adduction of the socket) and translational (5mm and 10mm of anterior, posterior, medial or lateral translation of the socket) alignment changes were performed in either the sagittal or the coronal plane in a randomized manner. A total of 17 alignment conditions were tested. Coronal angulation and translation alignment changes demonstrated similar consistent changes in the moment-moment curves. Sagittal alignment changes demonstrated more complex changes compared to the coronal alignment changes. Effect of sagittal angulations and translations on the moment-moment curves was different during 2nd rocker (mid-stance) with extension malalignment appearing to cause medio-lateral instability. Presentation of coronal and sagittal socket reaction moment interactions may provide useful visual information for prosthetists to understand the biomechanical effects of malalignment of transtibial prostheses. Copyright © 2013 Elsevier Ltd. All rights reserved.
The reconstruction of a contracted eye socket using a post-auricular full-thickness skin graft.
Wei, Yi Hsuan; Liao, Shu Lang
2014-05-01
To report the efficacy of a full-thickness skin graft (FTSG) for the reconstruction of a contracted eye socket. A retrospective, non-comparative, interventional case series. This was a retrospective review of patients with a contracted eye socket who underwent socket reconstruction using a post-auricular FTSG from 2001 to 2011 at the National Taiwan University Hospital. The postoperative results including prosthetic fitting, the cosmetic result, and eyelid function were assessed. There were 11 male and 15 female patients, with a mean age of 52.3 ± 15.6 years (range 21 to 76). The duration of the socket contracture varied from three months to three years (average 7.4 ± 8.1 months). The severity of the socket contracture ranged from grade 2 to grade 4, based on Tawfik's classification. The mean follow-up time was 35.7 ± 9.6 months. After socket reconstruction, using a post-auricular FTSG, 96% of the cases (25 of 26) demonstrated a successful prosthetic fitting and a satisfactory cosmetic outcome. Both good eyelid function and a stable fornix depth were maintained during the follow-up time. One case received a second socket reconstruction three months after the first operation, using a FTSG, because of an inadequate lateral fornix. The final result was satisfactory. There were no serious complications, but a granuloma formed in one case, and there was prolonged discharge in one case. The reconstruction of a contracted eye socket using a post-auricular FTSG is an effective method with a high success rate, which causes less discomfort to donor sites and results in few complications.
Research on Kinematic Trajectory Simulation System of KUKA Arc Welding Robot System
NASA Astrophysics Data System (ADS)
Hu, Min
2017-10-01
In this paper, the simulation trajectory simulation of KUKA arc welding robot system is realized by means of VC platform. It is used to realize the teaching of professional training of welding robot in middle school. It provides teaching resources for the combination of work and study and integration teaching, which enriches the content of course teaching.
Kotsakis, Georgios A; Joachim, Frederic P C; Saroff, Stephen A; Mahesh, Lanka; Prasad, Hari; Rohrer, Michael D
2014-01-01
The objective of this study was to evaluate bone regeneration in 24 sockets grafted with a calcium phosphosilicate putty alloplastic bone substitute. A core was obtained from 17 sockets prior to implant placement for histomorphometry at 5 to 6 months postextraction. Radiographic analysis during the same postextraction healing period showed radiopaque tissue in all sockets. Histomorphometric analysis revealed a mean vital bone content of 31.76% (± 14.20%) and residual graft content of 11.47% (± 8.99%) after a mean healing period of 5.7 months. The high percentage of vital bone in the healed sites in combination with its timely absorption rate suggest that calcium phosphosilicate putty can be a reliable choice for osseous regeneration in extraction sockets.
Prosthetic Correction of Postenucleation Socket Syndrome: A Case Report.
Kamble, Vikas B
2014-12-01
Postenucleation socket syndrome is a frequent late complication of enucleation of eye globe. Several pathophysiological mechanisms have been proposed to account for the symptoms of postenucleation socket syndrome, which include lost orbital volume, superior sulcus deformity, upper eyelid ptosis, lower eyelid laxity, and backward tilt of the prosthesis. The goal of postenucleation socket syndrome treatment is to achieve the best possible functional and esthetic result. The treatment can be either conservative or surgical. For the patient interested in a non-surgical correction, the conservative treatment is simple and non invasive and can be done with prosthesis modification for good positioning, comfort, and mobility. This paper describes prosthetic correction of a patient with postenucleation socket syndrome by modified ocular prosthesis.
Shakibaie-M, Behnam
2013-01-01
The aim of this study was to compare the effectiveness of two bone substitute materials for socket preservation after tooth extraction. Extraction sockets in 10 patients were filled with either inorganic bovine bone material (Bio-Oss) or with synthetic material consisting of hydroxyapatite and silicon dioxide (NanoBone). Extraction sockets without filling served as the control. The results demonstrate the effectiveness of the presented protocol for socket preservation and that the choice of a suitable bone substitute material is crucial. The dimensions of the alveolar ridge were significantly better preserved with Bio-Oss than with NanoBone or without treatment. Bio-Oss treatment resulted in better bone quality and quantity for successful implant placement.
Matin, Khalrul; Senpuku, Hidenobu; Hanada, Nobuhiro; Ozawa, Hidehiro; Ejiri, Sadakazu
2003-01-01
Difficulties relating to bone regeneration that complicate immediate implant placement include buccal and/or lingual fenestrations, primary anchorage of the implants, and the need for protection from functional loading during the osseointegration period. The objective of this pilot study was to evaluate bone regeneration by recombinant human bone morphogenetic protein-2 (rhBMP-2) around immediate implants placed in maxillary sockets in rats. A total of 16 cylindric 0.8 x 1.8-mm commercially pure, solid titanium Implants were placed immediately after gentle extraction of the maxillary first molar teeth of 8 male Wistar rats. The sockets were randomly divided into 3 groups: group 1 (n = 6) received rhBMP-2 with polylactic acid/polyglycolic acid copolymer-coated gelatin sponge carrier; group 2 (n = 5) received only the carrier; and group 3 (n = 5) received no grafting materials following placement The rats were euthanized at 90 days postsurgery for microscopic analysis. In group 1, the implant body remained submerged completely, including the coronal part, which was fully covered by a significant amount (30% of total height) of regenerated cortical bone, even though the implant could easily be pulled out by a tweezer at the time of placement. Close approximation between the implant surface and regenerated bone could also be detected, indicating good bone-to-implant contact. In contrast, only peri-implant bone regeneration occurred in group 2, and an approximate 0.3-mm coronal part of the implant remained exposed. When no grafting materials were used (group 3), almost one third of the total length of the implant was exfoliated out of the socket when no grafting materials were used. Based on previous study and data from 16 sockets of the present study, it could be concluded that rhBMP-2 facilitated the regeneration of bone around immediate implants. In particular, the bone covering the coronal part could have been regenerated shortly after surgery, which helped to maintain the implant body inside the socket during the integration period in rats.
2012-10-01
materials to facilitate dissemination of this technique. 15. SUBJECT TERMS Transfemoral amputation, sub-ischial socket, prosthesis , vacuum-assisted...an appropriate mechanical pump to create suitable vacuum for suspension of the prosthesis ...sockets of highly active prosthesis users
Zhou, Fengjuan; Zheng, Xiaofei; Xie, Meng; Mo, Anchun; Wu, Hongkun
2017-06-01
To evaluate the microenvironment changes in the sockets substituted with bovine-derived xenografts during the early healing period. After extraction of the right maxillary incisor of Sprague Dawley rats, 48 rats were randomly divided into 2 groups. The extraction sockets of the test group were filled with Bio-Oss, whereas the control group was allowed to heal without intervention. The bone quality of the extraction sockets was observed through micro-CT and immunohistochemistry. Micro-CT scanning showed that the bone mineral density in the test group was significantly higher than that in the control group during the early healing period, whereas immunohistochemistry showed that the bone formation-related factors were significantly different between the test and control groups. The bovine-derived xenografts may interfere with the healing process of the extraction socket in the early healing stage. Bone formation of the extraction socket was delayed after grafting with bone substitute.
The research of PSD location method in micro laser welding fields
NASA Astrophysics Data System (ADS)
Zhang, Qiue; Zhang, Rong; Dong, Hua
2010-11-01
In the field of micro laser welding, besides the special requirement in the parameter of lasers, the locating in welding points accurately is very important. The article adopt position sensitive detector (PSD) as hard core, combine optic system, electric circuits and PC and software processing, confirm the location of welding points. The signal detection circuits adopt the special integrate circuit H-2476 to process weak signal. It is an integrated circuit for high-speed, high-sensitivity optical range finding, which has stronger noiseproof feature, combine digital filter arithmetic, carry out repair the any non-ideal factors, increasing the measure precision. The amplifier adopt programmable amplifier LTC6915. The system adapt two dimension stepping motor drive the workbench, computer and corresponding software processing, make sure the location of spot weld. According to different workpieces to design the clamps. The system on-line detect PSD 's output signal in the moving processing. At the workbench moves in the X direction, the filaments offset is detected dynamic. Analyze the X axes moving sampling signal direction could be estimate the Y axes moving direction, and regulate the Y axes moving values. The workbench driver adopt A3979, it is a stepping motor driver with insert transducer and operate easily. It adapts the requirement of location in micro laser welding fields, real-time control to adjust by computer. It can be content up 20 μm's laser micro welding requirement on the whole. Using laser powder cladding technology achieve inter-penetration welding of high quality and reliability.
Influence of the Strength Mismatch of a Narrow Gap Welded Joint of SA508 on the Plastic η Factor
NASA Astrophysics Data System (ADS)
Koo, J. M.; Huh, Y.; Seok, C. S.
2012-11-01
In this article, the influence of the strength mismatch of a narrow gap welded joint of SA508 on the η factor was evaluated. The η factor is the principal parameter that determines the plastic portion of the J-integral. The specimens for tensile and hardness tests were collected from piping with narrow gap welding and the stress-strain curve and hardness were obtained from those. From these results, the Ramberg-Osgood (R-O) constant was obtained. Also, the finite element analysis was performed with variations in the strength mismatch and the weld width. The η factor equation considering the strength mismatch and the weld width of a narrow gap welded joint was suggested.
Reis-Filho, Cláudio R; Silva, Elisângela R; Martins, Adalberto B; Pessoa, Fernanda F; Gomes, Paula V N; de Araújo, Mariana S C; Miziara, Melissa N; Alves, José B
2012-05-01
In this study we investigated the possible use of human demineralised dentine matrix (DHDM), obtained from the extracted teeth, as bone graft material and evaluated the expression of vascular endothelial growth factor (VEGF) induced by this material in the healing process of tooth sockets of rats. To evaluate bone regeneration and expression of VEGF induced by DHDM, thirty-two male Wistar rats weighing approximately 200 g were used. After maxillary second molar extraction, the left sockets were filled with DHDM and the right sockets were naturally filled by blood clot (control). The animals were sacrificed at 3, 7, 14 and 21 days after surgery and upper maxillaries were processed for histological, morphometric and immunohistochemical analyses. DHDM was used to evaluate the mechanical effect of bone graft material into sockets. Expression of VEGF was determined by immunohistochemistry in all groups. Our results demonstrated a significant increase in the newly formed bone tissue in sockets of 7, 14 and 21 days and a significant increase in VEGF expression at days 7 and 14 on treated sockets. Our results showed that DHDM increases the expression of VEGF and accelerates the healing process in rats tooth sockets, by stimulating bone deposition and also vessels formation. These results suggest that DHDM has osteoinductive/osteoconductive potential and may represent an efficient grafting material on guided bone regeneration. Copyright © 2011 Elsevier Ltd. All rights reserved.
Ultrasonic technique for inspection of GPHS capsule girth weld integrity
NASA Astrophysics Data System (ADS)
Placr, Arnost
1993-05-01
An innovative nondestructive examination (NDE) technique for the inspection of integrity of General Purpose Heat Source (GPHS) capsule girth welds was developed employing a Lamb wave as the mode of the sound propagation. Reliability of the Lamb wave technique was tested on GPHS capsules using plutonium pallet simulators. All ten capsules, which were previously rejected, passed ultrasonic (UT) inspection using the Lamb wave technique.
Computational modeling of GTA (gas tungsten arc) welding with emphasis on surface tension effects
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zacharia, T.; David, S.A.
1990-01-01
A computational study of the convective heat transfer in the weld pool during gas tungsten arch (GTA) welding of Type 304 stainless steel is presented. The solution of the transport equations is based on a control volume approach which utilized directly, the integral form of the governing equations. The computational model considers buoyancy and electromagnetic and surface tension forces in the solution of convective heat transfer in the weld pool. In addition, the model treats the weld pool surface as a deformable free surface. The computational model includes weld metal vaporization and temperature dependent thermophysical properties. The results indicate thatmore » consideration of weld pool vaporization effects and temperature dependent thermophysical properties significantly influence the weld model predictions. Theoretical predictions of the weld pool surface temperature distributions and the cross-sectional weld pool size and shape wee compared with corresponding experimental measurements. Comparison of the theoretically predicted and the experimentally obtained surface temperature profiles indicated agreement with {plus minus} 8%. The predicted weld cross-section profiles were found to agree very well with actual weld cross-sections for the best theoretical models. 26 refs., 8 figs.« less
NASA Technical Reports Server (NTRS)
Nabors, Sammy
2015-01-01
NASA Marshall Space Flight Center (MSFC) developed Ultrasonic Stir Welding (USW) to join large pieces of very high-strength metals such as titanium and Inconel. USW, a solid-state weld process, improves current thermal stir welding processes by adding high-power ultrasonic (HPU) energy at 20 kHz frequency. The addition of ultrasonic energy significantly reduces axial, frictional, and shear forces; increases travel rates; and reduces wear on the stir rod, which results in extended stir rod life. The USW process decouples the heating, stirring, and forging elements found in the friction stir welding process allowing for independent control of each process element and, ultimately, greater process control and repeatability. Because of the independent control of USW process elements, closed-loop temperature control can be integrated into the system so that a constant weld nugget temperature can be maintained during welding.
Development of a gas pressure bonded four-pole alternator rotor
NASA Technical Reports Server (NTRS)
Lessmann, G. G.; Bryant, W. A.
1972-01-01
Methods were developed for fabrication of a solid four pole alternator rotor by hot isostatic pressure welding. The rotor blanks welded in this program had complex geometrical mating interfaces and were of considerable bulk, being approximately 3-1/2 inches (0.089 meters) in diameter and 14 inches (0.356 meters) long. Magnetic end pieces were machined from AlSl 4340 steel, while the non-magnetic central section was of Inconel 718. Excellent welds were produced which were shown to be responsive to post weld heat treatments which substantially improved joint strength. Prior to welding the rotors, test specimens of complex geometry were welded to demonstrate that complex surfaces with intentional mechanical misfit could be readily joined using HIP welding. This preliminary work demonstrated not only that interface compliance is achieved during welding but that welding pressure is developed in these thick sections sufficient to produce sound joints. Integral weld-heat treatment cycles were developed that permitted the attainment of magnetic properties while minimizing residual stress associated with the allotropic transformation of 4340 steel.
46 CFR 161.006-4 - Requirements.
Code of Federal Regulations, 2010 CFR
2010-10-01
... parts: Yoke and pedestal. Housing. Front door. Reflector. Lamp socket. Supply cable. (c) Weight and... socket. The motor lifeboat searchlight shall be provided with a lamp of not less than 80 watts nor more than 100 watts, and a suitable lamp socket. Means shall be provided for adjusting and securing the lamp...
46 CFR 161.006-4 - Requirements.
Code of Federal Regulations, 2012 CFR
2012-10-01
... parts: Yoke and pedestal. Housing. Front door. Reflector. Lamp socket. Supply cable. (c) Weight and... socket. The motor lifeboat searchlight shall be provided with a lamp of not less than 80 watts nor more than 100 watts, and a suitable lamp socket. Means shall be provided for adjusting and securing the lamp...
46 CFR 161.006-4 - Requirements.
Code of Federal Regulations, 2014 CFR
2014-10-01
... parts: Yoke and pedestal. Housing. Front door. Reflector. Lamp socket. Supply cable. (c) Weight and... socket. The motor lifeboat searchlight shall be provided with a lamp of not less than 80 watts nor more than 100 watts, and a suitable lamp socket. Means shall be provided for adjusting and securing the lamp...
46 CFR 161.006-4 - Requirements.
Code of Federal Regulations, 2011 CFR
2011-10-01
... parts: Yoke and pedestal. Housing. Front door. Reflector. Lamp socket. Supply cable. (c) Weight and... socket. The motor lifeboat searchlight shall be provided with a lamp of not less than 80 watts nor more than 100 watts, and a suitable lamp socket. Means shall be provided for adjusting and securing the lamp...
46 CFR 161.006-4 - Requirements.
Code of Federal Regulations, 2013 CFR
2013-10-01
... parts: Yoke and pedestal. Housing. Front door. Reflector. Lamp socket. Supply cable. (c) Weight and... socket. The motor lifeboat searchlight shall be provided with a lamp of not less than 80 watts nor more than 100 watts, and a suitable lamp socket. Means shall be provided for adjusting and securing the lamp...
2013-10-01
15. SUBJECT TERMS Transfemoral amputation, sub-ischial socket, prosthesis , vacuum-assisted suspension 16. SECURITY CLASSIFICATION OF: 17...vacuum for suspension of the prosthesis ...14 Task 6 Determine range of volumes to be evacuated from transfemoral sockets of highly active prosthesis users
Convertible socket for pressure gauge
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bissell, R.D.
1990-01-01
This patent describes a pressure gauge having a case in which is disposed a Bourdon tube and a base socket connected to the Bourdon tube for placing the tube in pressure communication with a fluid pressure source. Base socket has a rearward face and a bottom face with respect to the gauge adjacent openings defined through the case and an internal passage communication with the tube. It includes means for connecting a source of fluid pressure to the socket selectively through one of the case openings to the bottom face or the rearward face.
The possible nature of socket stars in H II regions
NASA Technical Reports Server (NTRS)
Castelaz, Michael W.
1990-01-01
Close inspection of faint stars (V of about 14 mag) in H II regions show that they appear to be surrounded by circumstellar envelopes of about 10 arcsecs in diameter (as reported by Feibelman in 1989). The present premise is that the sockets are envelopes of obscuring dust which should emit a measurable amount of infrared radiation based on a simple thermal equilibrium model. A search of literature shows that, of 36 socket stars listed by Feibelman, 17 have been measured in the infrared. Of the 17, 14 show excess IR emission. This is very strong evidence that the socket stars are really stars with circumstellar envelopes. Socket stars may be a new type of astronomical object or well-known astronomical objects in environments or evolutionary states not previously seen.
Double arch mirror study. Part 1: Preliminary engineering report
NASA Technical Reports Server (NTRS)
Vukobratovich, D.; Hillman, D.
1983-01-01
In the proposed design, the NASA AMES 20-in double arch mirror is supported by three clamp and flexure assemblies. The mirror clamp consists of a T-shaped Invar-36 member that goes into a similarly shaped socket in the back of the mirror. The mirror socket is made oversize and contacts the clamp only along the conical surface. The clamp is preloaded by a spring washer and pulls the mirror into contact with the flexure. The clamp is then inserted into the mirror socket through a cutout, is rotated 90 deg, and is then pinned in place. Loading conditions considered in socket design are discussed as well as stress in the socket and clamp. Flexure geometry and stress are examined as well as the effects of flexure error and of mirror cell error.
Manavella, Valeria; Romano, Federica; Garrone, Federica; Terzini, Mara; Bignardi, Cristina; Aimetti, Mario
2017-06-01
The aim of this study was to present and validate a novel procedure for the quantitative volumetric assessment of extraction sockets that combines cone-beam computed tomography (CBCT) and image processing techniques. The CBCT dataset of 9 severely resorbed extraction sockets was analyzed by means of two image processing software, Image J and Mimics, using manual and automated segmentation techniques. They were also applied on 5-mm spherical aluminum markers of known volume and on a polyvinyl chloride model of one alveolar socket scanned with Micro-CT to test the accuracy. Statistical differences in alveolar socket volume were found between the different methods of volumetric analysis (P<0.0001). The automated segmentation using Mimics was the most reliable and accurate method with a relative error of 1.5%, considerably smaller than the error of 7% and of 10% introduced by the manual method using Mimics and by the automated method using ImageJ. The currently proposed automated segmentation protocol for the three-dimensional rendering of alveolar sockets showed more accurate results, excellent inter-observer similarity and increased user friendliness. The clinical application of this method enables a three-dimensional evaluation of extraction socket healing after the reconstructive procedures and during the follow-up visits.
Vignoletti, Fabio; Discepoli, Nicola; Müller, Anna; de Sanctis, Massimo; Muñoz, Fernando; Sanz, Mariano
2012-01-01
The purpose of this investigation is to describe histologically the undisturbed healing of fresh extraction sockets when compared to immediate implant placement. In eight beagle dogs, after extraction of the 3P3 and 4P4, implants were inserted into the distal sockets of the premolars, while the mesial sockets were left to heal spontaneously. Each animal provided four socket sites (control) and four implant sites (test). After 6 weeks, animals were sacrificed and tissue blocks were dissected, prepared for ground sectioning. The relative vertical buccal bone resorption in relation to the lingual bone was similar in both test and control groups. At immediate implant sites, however, the absolute buccal bone loss observed was 2.32 (SD 0.36) mm, what may indicate that while an apical shift of both the buccal and lingual bone crest occurred at the implant sites, this may not happen in naturally healing sockets. The results from this investigation showed that after tooth extraction the buccal socket wall underwent bone resorption at both test and control sites. This resorption appeared to be more pronounced at the implant sites, although the limitations of the histological evaluation method utilized preclude a definite conclusion. © 2011 John Wiley & Sons A/S.
Requena-Calla, Silvana; Funes-Rumiche, Italo
2016-04-01
Dry socket is one of the most studied complications in dentistry and several studies have sought an effective and safe method for its prevention and treatment. The aim of this study was to evaluate the effectiveness of intra-alveolar gel chlorhexidine in preventing dry socket after the surgical removal of third molars. The sample involved the treatment of 40 patients who required extraction of third molars impacted, which were randomly assigned to research groups: experimental group (chlorhexidine gel 0.12%) and control group (placebo gel). Performed the extraction was administered 1 mL of chlorhexidine gel or 1 mL of placebo gel within the socket. The removal of suture was on the fifth postoperative day in which the presence or absence of dry socket was evaluated. No relationship between the appearance of dry socket after application of chlorhexidine gel or placebo gel (X2 test, p = 0.311) was found. However, significant differences (U Mann-Whitney test, p = 0.036) in the pain presented on the fifth postoperative day were evident (VAS). The administration of intra-alveolar chlorhexidine gel 0.12% could generate a better response to postoperative pain after the removal of third molars. Third molar surgery, dry socket, chorhexidine gel.
Ball and Socket Ankle: Mechanism and Computational Evidence of Concept.
Jastifer, James R; Gustafson, Peter A; Labomascus, Aaron; Snoap, Tyler
The ball and socket ankle joint is a morphologically abnormal joint characterized by rounding of the articular surface of the talus. Other than anecdotal observation, little evidence has been presented to describe the development of this deformity. The purpose of the present study was to review ankle and subtalar joint mechanics and to kinematically examine the functional combination of these joints as a mechanism of the ball and socket ankle deformity. We reviewed functional representations of the ankle joint, subtalar joint, and ball and socket ankle deformity. A computational study of joint kinematics was then performed using a 3-dimensional model derived from a computed tomography scan of a ball and socket deformity. The joint kinematics were captured by creating a "virtual map" of the combined kinematics of the ankle and subtalar joints in the respective models. The ball and socket ankle deformity produces functionally similar kinematics to a combination of the ankle and subtalar joints. The findings of the present study support the notion that a possible cause of the ball and socket deformity is bony adaptation that compensates for a functional deficit of the ankle and subtalar joints. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.
Jiang, Xi; Zhang, Yu; Chen, Bo; Lin, Ye
2017-04-01
Extraction socket remodeling and ridge preservation strategies have been extensively explored. To evaluate the efficacy of applying a micro-titanium stent as a pressure bearing device on extraction socket remodeling of maxillary anterior tooth. Twenty-four patients with a extraction socket of maxillary incisor were treated with spontaneous healing (control group) or by applying a micro-titanium stent as a facial pressure bearing device over the facial bone wall (test group). Two virtual models obtained from cone beam computed tomography data before extraction and 4 months after healing were 3-dimenionally superimposed. Facial bone wall resorption, extraction socket remodeling features and ridge width preservation rate were determined and compared between the groups. Thin facial bone wall resulted in marked resorption in both groups. The greatest palatal shifting distance of facial bone located at the coronal level in the control group, but middle level in the test group. Compared with the original extraction socket, 87.61 ± 5.88% ridge width was preserved in the test group and 55.09 ± 14.46% in the control group. Due to the facial pressure bearing property, the rigid micro-titanium stent might preserve the ridge width and alter the resorption features of extraction socket. © 2016 Wiley Periodicals, Inc.
Gerard, David A; Carlson, Eric R; Gotcher, Jack E; Pickett, David O
2014-01-01
This study was conducted with 2 purposes. The first was to determine the effect of a single dose of zoledronic acid (ZA) on the healing of a tooth extraction socket in dogs. The second was to determine if placement of recombinant human bone morphogenetic protein-2 (rhBMP-2)/absorbable collagen sponge (ACS) - INFUSE, (Medtronic, Memphis, TN) into these extraction sockets would inhibit the inhibition on bone healing and remodeling by ZA. Nine adult female beagle dogs (2 to 3 yr old) were placed into 3 groups of 3 dogs each. Group I received 15 mL of sterile saline intravenously; group II received 2.5 mg of ZA intravenously; and group III received 5 mg of ZA intravenously. Forty-five days after treatment, all dogs underwent extraction of noncontiguous right and left mandibular first molars and second premolars. In group I, the right mandibular extraction sockets had nothing placed in them, whereas the left mandibular sockets had only ACS placed in them. In groups II and III, the right mandibular sockets had rhBMP-2/ACS placed in them, whereas the left mandibular sockets had only ACS placed. All extraction sockets were surgically closed. Tetracycline was given intravenously 5 and 12 days later, and all animals were euthanized 15 days after tooth extraction. The extraction sockets and rib and femur samples were harvested immediately after euthanasia, processed, and studied microscopically. A single dose of ZA significantly inhibited healing and bone remodeling in the area of the tooth extractions. The combination of rhBMP-2/ACS appeared to over-ride some of the bone remodeling inhibition of the ZA and increased bone fill in the extraction sites, and remodeling activity in the area was noted. The effects of rhBMP-2/ACS were confined to the area of the extraction sockets because bone activity at distant sites was not influenced. A single dose of ZA administered intravenously inhibits early healing of tooth extraction sockets and bone remodeling in this animal model. The combination of rhBMP-2/ACS significantly increased bone fill and bone remodeling in these areas, negating much of the effect of the ZA. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
Heberer, Susanne; Wustlich, Alexander; Lage, Hermann; Nelson, John J; Nelson, Katja
2012-01-01
The aim of the present clinical study was the evaluation of the osteogenic potential of mesenchymal cells embedded in the provisional matrix of non-augmented and with Bio-Oss collagen-augmented human extraction sockets after 6 weeks of healing time. Twenty-five patients with 47 extraction sites participated in the present study. After tooth removal, the extraction sockets were augmented with Bio-Oss collagen or not augmented. At implant placement, bone biopsies of the extraction sockets were obtained. The immunohistochemical analysis of the osteogenic potential of the mesenchymal cells in the provisional matrix was performed using three monoclonal antibodies: core-binding factor α1 (Cbfa1)/runt-related protein (Runx)2, osteonectin (OSN/secreted protein acidic and rich in cyst [SPARC]) and osteocalcin (OC). The statistical analysis was performed using two-factorial analysis for repeated measures, Mann-Whitney U-test and Spearman's rank-order correlation coefficient. Of 47 extraction sockets examined, 17 sockets demonstrated an almost complete ossification. Hence, the provisional matrix of the 30 remaining extraction sockets (21 non-augmented, 9 augmented) was immunohistochemically investigated. No evidence of acute or chronic inflammation was noted in any of the specimens. In the provisional matrix of the non-grafted socket, the median amount of Cbfa1/Runx2-positive cells was 72.3%, of OSN (SPARC) 66.9% and of OC 23.4%, whereas in the grafted sockets the median rate of immunopositive cells staining with Cbfa1/Runx2 was 73.3%, of OSN (SPARC) 61.4% and of OC 20.1%. There was no significant difference in the proportion of positive cells expressed by Cbfa1/Runx2, OSN/SPARC and OC between the grafted and non-grafted socket. Furthermore, the cell density did not correlate to the quantity of stained cells independent of the used proteins. After a 6-week healing period, the provisional matrix was demonstrated to have a high proportion of cells displaying a maturation of mature osteoprogenitor cells to osteoblasts. The grafting procedure did not influence the quantity of osteogenic cells in the extraction socket. © 2011 John Wiley & Sons A/S.
Samitier, C Beatriz; Guirao, Lluis; Costea, Maria; Camós, Josep M; Pleguezuelos, Eulogio
2016-02-01
Lower limb amputation leads to impaired balance, ambulation, and transfers. Proper fit of the prosthesis is a determining factor for successful ambulation. Vacuum-assisted socket systems extract air from the socket, which decreases pistoning and probability of soft-tissue injuries and increases proprioception and socket comfort. To investigate the effect of vacuum-assisted socket system on transtibial amputees' performance-based and perceived balance, transfers, and gait. Quasi-experimental before-and-after study. Subjects were initially assessed using their prosthesis with the regular socket and re-evaluated 4 weeks after fitting including the vacuum-assisted socket system. We evaluated the mobility grade using Medicare Functional Classification Level, Berg Balance Scale, Four Square Step Test, Timed Up and Go Test, the 6-Min Walk Test, the Locomotor Capabilities Index, Satisfaction with Prosthesis (SAT-PRO questionnaire), and Houghton Scale. A total of 16 unilateral transtibial dysvascular amputees, mean age 65.12 (standard deviation = 10.15) years. Using the vacuum-assisted socket system, the patients significantly improved in balance, gait, and transfers: scores of the Berg Balance Scale increased from 45.75 (standard deviation = 6.91) to 49.06 (standard deviation = 5.62) (p < 0.01), Four Square Step Test decreased from 18.18 (standard deviation = 3.84) s to 14.97 (3.9) s (p < 0.01), Timed Up and Go Test decreased from 14.3 (standard deviation = 3.29) s to 11.56 (2.46) s (p < 0.01). The distance walked in the 6-Min Walk Test increased from 288.53 (standard deviation = 59.57) m to 321.38 (standard deviation = 72.81) m (p < 0.01). Vacuum-assisted socket systems are useful for improving balance, gait, and transfers in over-50-year-old dysvascular transtibial amputees. This study gives more insight into the use of vacuum-assisted socket systems to improve elderly transtibial dysvascular amputees' functionality and decrease their risk of falls. The use of an additional distal valve in the socket should be considered in patients with a lower activity level. © The International Society for Prosthetics and Orthotics 2014.
Extravehicular activity welding experiment
NASA Technical Reports Server (NTRS)
Watson, J. Kevin
1989-01-01
The In-Space Technology Experiments Program (INSTEP) provides an opportunity to explore the many critical questions which can only be answered by experimentation in space. The objective of the Extravehicular Activity Welding Experiment definition project was to define the requirements for a spaceflight experiment to evaluate the feasibility of performing manual welding tasks during EVA. Consideration was given to experiment design, work station design, welding hardware design, payload integration requirements, and human factors (including safety). The results of this effort are presented. Included are the specific objectives of the flight test, details of the tasks which will generate the required data, and a description of the equipment which will be needed to support the tasks. Work station requirements are addressed as are human factors, STS integration procedures and, most importantly, safety considerations. A preliminary estimate of the cost and the schedule for completion of the experiment through flight and postflight analysis are given.
Wang, Song; Wang, Fei; Liao, Zhenhua; Wang, Qingliang; Liu, Yuhong; Liu, Weiqiang
2015-10-01
A ball-on-socket contact configuration was designed to simulate an artificial cervical disk in structure. UHMWPE (ultra high molecular weight polyethylene) hot pressed by powders and Ti6Al4V alloy were selected as the material combination of ball and socket. The socket surface was coated by a ~500 nm C-DLC (carbon ion implantation-diamond like carbon) mixed layer to improve its surface nano hardness and wear resistance. The torsional fretting wear behavior of the ball-on-socket model was tested at different angular displacements under 25% bovine serum lubrication with an axial force of 100 N to obtain more realistic results with that in vivo. The fretting running regimes and wear damage characteristics as well as wear mechanisms for both ball and socket were studied based on 2D (two dimension) optical microscope, SEM (scanning electron microscope) and 3D (three dimension) profiles. With the increase of angular displacement amplitude from 1° to 7°, three types of T-θ (Torsional torque-angular displacement amplitude) curves (i.e., linear, elliptical and parallelogram loops) corresponding to running regimes of PSR (partial slip regime), MR (mixed regime) and SR (slip regime) were observed and analyzed. Both the central region and the edge zone of the ball and socket were damaged. The worn surfaces were characterized by wear scratches and wear debris. In addition, more severe wear damage and more wear debris appeared on the central region of the socket at higher angular displacement amplitude. The dominant damage mechanism was a mix of surface scratch, adhesive wear and abrasive wear for the UHMWPE ball while that for the coated socket was abrasive wear by PE particles and some polishing and rolling process on the raised overgrown DLC grains. The frictional kinetic behavior, wear type, damage region and damage mechanism for the ball-on-socket model revealed significant differences with those of a ball-on-flat contact while showing better consistency with that of in vitro cervical prosthesis simulations according to the literature. Copyright © 2015. Published by Elsevier B.V.
ERIC Educational Resources Information Center
Samuel, Gabrielle; Donovan, Claire; Lee, Jeung
2018-01-01
The paper presents an evaluation of an MSc in Structural Integrity co-produced by Brunel University London and industry partner The Welding Institute (TWI), designed to supply 'work-ready' graduates. Pre-, mid- and post-course quantitative surveys were administered to students, and two mid-term focus groups were conducted. Pre- and post-course…
Control of arc length during gas metal arc welding
DOE Office of Scientific and Technical Information (OSTI.GOV)
Madigan, R.B.; Quinn, T.P.
1994-12-31
An arc-length control system has been developed for gas metal arc welding (GMAW) under spray transfer welding conditions. The ability to monitor and control arc length during arc welding allows consistent weld characteristics to be maintained and therefore improves weld quality. Arc length control has only been implemented for gas tungsten arc welding (GTAW), where an automatic voltage control (AVC) unit adjusts torch-to-work distance. The system developed here compliments the voltage- and current-sensing techniques commonly used for control of GMAW. The system consists of an arc light intensity sensor (photodiode), a Hall-effect current sensor, a personal computer and software implementingmore » a data interpretation and control algorithms. Arc length was measured using both arc light and arc current signals. Welding current was adjusted to maintain constant arc length. A proportional-integral-derivative (PID) controller was used. Gains were automatically selected based on the desired welding conditions. In performance evaluation welds, arc length varied from 2.5 to 6.5 mm while welding up a sloped workpiece (ramp in CTWD) without the control. Arc length was maintained within 1 mm of the desired (5 mm ) with the control.« less
Demonstration of a Large-Scale Tank Assembly via Circumferential Friction Stir Welds
NASA Technical Reports Server (NTRS)
Jones, Clyde S.; Adams, Glynn; Colligan, Kevin
2000-01-01
A collaborative effort between NASA/Marshall Space Flight Center and the Michoud Unit of Lockheed Martin Space Systems Company was undertaken to demonstrate assembly of a large-scale aluminum tank using circumferential friction stir welds. The hardware used to complete this demonstration was fabricated as a study of near-net- shape technologies. The tooling used to complete this demonstration was originally designed for assembly of a tank using fusion weld processes. This presentation describes the modifications and additions that were made to the existing fusion welding tools required to accommodate circumferential friction stir welding, as well as the process used to assemble the tank. The tooling modifications include design, fabrication and installation of several components. The most significant components include a friction stir weld unit with adjustable pin length capabilities, a continuous internal anvil for 'open' circumferential welds, a continuous closeout anvil, clamping systems, an external reaction system and the control system required to conduct the friction stir welds and integrate the operation of the tool. The demonstration was intended as a development task. The experience gained during each circumferential weld was applied to improve subsequent welds. Both constant and tapered thickness 14-foot diameter circumferential welds were successfully demonstrated.
An Amino Acid Code for β-sheet Packing Structure
Joo, Hyun; Tsai, Jerry
2014-01-01
To understand the relationship between protein sequence and structure, this work extends the knob-socket model in an investigation of β-sheet packing. Over a comprehensive set of β-sheet folds, the contacts between residues were used to identify packing cliques: sets of residues that all contact each other. These packing cliques were then classified based on size and contact order. From this analysis, the 2 types of 4 residue packing cliques necessary to describe β-sheet packing were characterized. Both occur between 2 adjacent hydrogen bonded β-strands. First, defining the secondary structure packing within β-sheets, the combined socket or XY:HG pocket consists of 4 residues i,i+2 on one strand and j,j+2 on the other. Second, characterizing the tertiary packing between β-sheets, the knob-socket XY:H+B consists of a 3 residue XY:H socket (i,i+2 on one strand and j on the other) packed against a knob B residue (residue k distant in sequence). Depending on the packing depth of the knob B residue, 2 types of knob-sockets are found: side-chain and main-chain sockets. The amino acid composition of the pockets and knob-sockets reveal the sequence specificity of β-sheet packing. For β-sheet formation, the XY:HG pocket clearly shows sequence specificity of amino acids. For tertiary packing, the XY:H+B side-chain and main-chain sockets exhibit distinct amino acid preferences at each position. These relationships define an amino acid code for β-sheet structure and provide an intuitive topological mapping of β-sheet packing. PMID:24668690
Evaluation of osteoblastic activity in extraction sockets treated with platelet-rich fibrin
Tumer, Celal; Ugur, Omer; Vatankulu, Betul
2015-01-01
Objective: The aim of this study was to determine whether the use of platelet rich fibrin (PRF) improved the healing of extraction sockets. Study Design: A total of 20 patients with bilateral soft tissue impacted mandibular third molars were included in this study. The left and right third molars were extracted during the same session. Subsequently, the PRF membrane was randomly administered to one of the extraction sockets, whereas the contra lateral sockets were left without treatment. On postoperative 30. and 90. days, panoramic images and bone scintigrams were taken to evaluate the bone healing between PRF-treated and non-PRF-treated sockets. Also, periodontal evaluation was performed in the same control sessions. Dependent group t test for paired samples was used for statistical analysis. Results: The average increase in technetium-99m methylene diphosphonate uptake as an indication of enhanced bone healing did not differ significantly between PRF-treated and non-PRF-treated sockets 30 and 90 days post operatively. Radio opacity that can show the bone healing on panoramic images were measured by Image J programmer and they did not differ significantly. Also periodontal values did not differ significantly. Conclusions: PRF might not lead to enhanced bone healing in impacted mandibular third molar extraction sockets 30 and 90 days after surgery. It is thought that PRF has the potential characteristics of an autologous fibrin matrix and can accelerate the healing. To better understand the effects of PRF on healing, further research is warranted with larger sample sizes. Key words:PRF, scintigraphy, healing, extraction sockets. PMID:25475771
Platelet rich fibrin in the management of established dry socket.
Chakravarthi, Srinivas
2017-06-01
Dry socket may occur secondary to the removal of any tooth. However, most dry socket cases develop in the third molar region. Dry socket is multifactorial in nature and has been treated using various modalities with varying success rates. This study assessed the efficacy of platelet rich fibrin (PRF) in established dry socket. Ten patients of either sex aged from 41 to 64 years with established dry socket according to established criteria were treated using PRF. Evaluation was performed by observing the reduction of pain using visual analogue scale, analgesic tablet use over the follow-up period, and healing parameters. Pain was reduced on the first day in all patients with decreased analgesic use. Pain was drastically reduced during follow-up on the first, second, third, and seventh days with a fall in pain score of 0 to 1 after the first day alone. The pain scores of all patients decreased to 1 by the first day except in one patient, and the scores decreased to 0 in all patients after 48 hours. Total analgesic intake ranged from 2 to 6 tablets (aceclofenac 100 mg per tablet) over the follow-up period of 7 days. Healing was satisfactory in all patients by the end of the seventh day. PRF showed early pain reduction in established dry socket with minimal analgesic intake. No patients had allergic reactions to PRF as it is derived from the patient's own blood. PRF showed good wound healing. Our study suggests that PRF should be considered as a treatment modality for established dry socket.
Kobayashi, Toshiki; Arabian, Adam K.; Orendurff, Michael S.; Rosenbaum-Chou, Teri G.; Boone, David A.
2014-01-01
Background Energy storage and return feet are designed for active amputees. However, little is known about the socket reaction moments in transtibial prostheses with energy storage and return feet. The aim of this study was to investigate the effect of alignment changes on the socket reaction moments during gait while using the energy storage and return feet. Methods A Smart Pyramid™ was used to measure the socket reaction moments in 10 subjects with transtibial prostheses while walking under 25 alignment conditions, including a nominal alignment (as defined by conventional clinical methods), as well as angle malalignments of 2°, 4° and 6° (flexion, extension, abduction, and adduction) and translation malalignments of 5mm, 10mm and 15mm (anterior, posterior, lateral, and medial) referenced from the nominal alignment. The socket reaction moments of the nominal alignment were compared with each malalignment. Findings Both coronal and sagittal alignment changes demonstrated systematic effects on the socket reaction moments. In the sagittal plane, angle and translation alignment changes demonstrated significant differences (P<0.05) in the minimum moment, the moment at 45% of stance and the maximum moment for some comparisons. In the coronal plane, angle and translation alignment changes demonstrated significant differences (P<0.05) in the moment at 30% and 75% of stance for all comparisons. Interpretation The alignment may have systematic effects on the socket reaction moments in transtibial prostheses with energy storage and return feet. The socket reaction moments could potentially be a useful biomechanical parameter to evaluate the alignment of the transtibial prostheses. PMID:24315709
Sharma, Ashish; Aggarwal, Nimish; Rastogi, Sanjay; Choudhury, Rupshikha; Tripathi, Siddhi
2017-01-01
To assess the efficacy of platelet-rich fibrin (PRF) on the pain and healing of the extraction socket related with established alveolar osteitis (dry socket, AO) after the removal of maxillary and mandibular molars. One hundred consecutive adult patients with age group ranging from 18 to 40 years along with established dry socket after maxillary and mandibular molar extractions who have not received any treatment for the same were included in this single-arm clinical trial. PRF was placed in the maxillary and mandibular molar extraction sockets after adequate irrigation of the socket. All the patients evaluated for the various study variables which include pain, degree of inflammation, and healthy granulation tissue formation (wound healing) at the 1 st , 3 rd , 7 th , and 14 th post-PRF placement day in the alveolar socket. Data were analyzed using Shapiro-Wilk's test, Chi-square test and/or Student's t -test, Friedman's test, Wilcoxon signed-rank test, and Bonferroni test, with the significance level set at P < 0.05. There was significant reduction in pain associated with AO at the 3 rd and 7 th post-PRF placement day in the extraction socket along with mark decrease in the degree of inflammation at the 3 rd post-PRF placement day, and there was better wound healing by the end of the 2 nd week. The use of PRF in this clinical trial illustrates the promising results in terms of reduced pain and better healing in the patients with sustained AO.
Moghaddas, Hamid; Amjadi, Mohammad Reza; Naghsh, Narges
2012-11-01
Alveolar ridge preservation following tooth extraction has the ability to maintain the ridge dimensions and allow the implant placement in an ideal position fulfilling both functional and aesthetic results. The aim of this study was to evaluate the efficacy of the palatal connective tissue as a biological membrane for socket preservation with demineralized freeze-dried bone allograft (DFDBA). Twelve extraction sites were treated with DFDBA with (case group) and without (control group) using autogenous palatal connective tissue membrane before placement of implants. Alveolar width and height, amount of keratinized tissue, and gingival level were measured at pre-determined points using a surgical stent at two times, the time of socket preservation surgery. In both groups a decrease in all socket dimensions was found. The average decrease in socket width, height, keratinized tissue, and gingival level in case group was 1.16, 0.72, 3.58, and 1.27 mm, and in control group was 2.08, 0.86, 4.52, and 1.58 mm respectively. Statistical analysis showed that decrease in socket width (P = 0.012), keratinized tissue (P ≤ 0.001), and gingival level (P = 0.031) in case group was significantly lower than that of the control group. Results showed no meaningful difference in socket height changes when compared with case and control groups (P = 0.148). Under the limits of this study, connective tissue membrane could preserve socket width, amount of keratinized tissue, and the gingival level more effectively than DFDBA alone.
Platelet rich fibrin in the management of established dry socket
2017-01-01
Objectives Dry socket may occur secondary to the removal of any tooth. However, most dry socket cases develop in the third molar region. Dry socket is multifactorial in nature and has been treated using various modalities with varying success rates. This study assessed the efficacy of platelet rich fibrin (PRF) in established dry socket. Materials and Methods Ten patients of either sex aged from 41 to 64 years with established dry socket according to established criteria were treated using PRF. Evaluation was performed by observing the reduction of pain using visual analogue scale, analgesic tablet use over the follow-up period, and healing parameters. Results Pain was reduced on the first day in all patients with decreased analgesic use. Pain was drastically reduced during follow-up on the first, second, third, and seventh days with a fall in pain score of 0 to 1 after the first day alone. The pain scores of all patients decreased to 1 by the first day except in one patient, and the scores decreased to 0 in all patients after 48 hours. Total analgesic intake ranged from 2 to 6 tablets (aceclofenac 100 mg per tablet) over the follow-up period of 7 days. Healing was satisfactory in all patients by the end of the seventh day. Conclusion PRF showed early pain reduction in established dry socket with minimal analgesic intake. No patients had allergic reactions to PRF as it is derived from the patient's own blood. PRF showed good wound healing. Our study suggests that PRF should be considered as a treatment modality for established dry socket. PMID:28770156
Surface EMG and intra-socket force measurement to control a prosthetic device
NASA Astrophysics Data System (ADS)
Sanford, Joe; Patterson, Rita; Popa, Dan
2015-06-01
Surface electromyography (SEMG) has been shown to be a robust and reliable interaction method allowing for basic control of powered prosthetic devices. Research has shown a marked decrease in EMG-classification efficiency throughout activities of daily life due to socket shift and movement and fatigue as well as changes in degree of fit of the socket throughout the subject's lifetime. Users with the most severe levels of amputation require the most complex devices with the greatest number of degrees of freedom. Controlling complex dexterous devices with limited available inputs requires the addition of sensing and interaction modalities. However, the larger the amputation severity, the fewer viable SEMG sites are available as control inputs. Previous work reported the use of intra-socket pressure, as measured during wrist flexion and extension, and has shown that it is possible to control a powered prosthetic device with pressure sensors. In this paper, we present data correlations of SEMG data with intra-socket pressure data. Surface EMG sensors and force sensors were housed within a simulated prosthetic cuff fit to a healthy-limbed subject. EMG and intra-socket force data was collected from inside the cuff as a subject performed pre-defined grip motions with their dominant hand. Data fusion algorithms were explored and allowed a subject to use both intra-socket pressure and SEMG data as control inputs for a powered prosthetic device. This additional input modality allows for an improvement in input classification as well as information regarding socket fit through out activities of daily life.
A new directly moulded patellar-tendon-bearing socket.
Boot, D A; Young, N J
1985-08-01
Silicone rubbers and casting tapes individually have previously been used in the manufacture of sockets (Swanson, 1972; Sweitzer, 1973; Ruder, 1977; Graves, 1980; Aqualite, 1982). The authors believe that the present combination of these materials to manufacture a directly moulded socket with a complete silicone rubber lining of variable thickness has not previously been described. The new socket, after addition of the modular components, allows fitting of an aligned below-knee prosthesis within three hours. The socket (Fig. 1.) is made directly on the below-knee stump, can be completed with experience in an hour and does not require the use of specialized equipment. The socket consists of an outer supportive Scotchflex layer inside which is a lining of soft smooth biocompatible silicone rubber of deliberately variable thickness to allow pressure tolerant areas to accept more load and pressure sensitive areas to accept less load (Fig.2). The thicker areas of silicone are produced by applying carefully cut Plastazote pads to the pressure sensitive areas. The thickness and extent of the pads is individually assessed according to the estimated sensitivity of the particular area (Fig. 3). The Scotchflex socket is then manufactured directly on the below-knee stump with these pads applied. The pads are then removed prior to insertion of a semi-liquid silicone rubber. Thus, when the socket with the liquid silicone rubber is re-applied to the stump, the space produced by the pads is filled by the rubber which then sets at room temperature. In this way a layer of variable thickness is produced.(ABSTRACT TRUNCATED AT 250 WORDS)
Mozzati, Marco; Gallesio, Giorgia; di Romana, Sara; Bergamasco, Laura; Pol, Renato
2014-03-01
To evaluate the efficacy of plasma-rich growth factor (PRGF) in improving socket healing after tooth extraction in diabetic patients. This was a split-mouth study in which each patient also served as the control: the study socket was treated with PRGF, whereas the control socket underwent natural healing. The outcome variables were the Healing Index, residual socket volume, visual analog scale score, postsurgical complications, and outcome of a patient questionnaire. The investigation considered the impact of hyperglycemia, glycated hemoglobin, End Organ Disease Score, and smoking habits. Follow-up included 4 postextraction checkups over a 21-day period. Pairs of correlated continuous variables were analyzed with the Wilcoxon test, independent continuous variables with the Mann-Whitney test, and categorical variables with the χ(2) test or Fisher test. From January 2012 to December 2012, 34 patients affected by insulin-dependent diabetes mellitus underwent contemporary bilateral extractions of homologous teeth. The treatment-versus-control postoperative comparison showed that PRGF resulted in significantly smaller residual socket volumes and better Healing Indices from days 3 to 14. The patients' questionnaire outcomes were unanimously in favor of PRGF treatment. The small sample of patients with glycemia values of at least 240 mg/dL showed worse Healing Index and minor socket decreases. PRGF application after extraction improved the healing process in diabetic patients by accelerating socket closure (epithelialization) and tissue maturation, proving the association between PRGF use and improved wound healing in diabetic patients. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
Small-scale explosive seam welding. [using ribbon explosive encased in lead sheath
NASA Technical Reports Server (NTRS)
Bement, L. J.
1972-01-01
A unique small scale explosive seam welding technique is reported that has successfully joined a variety of aluminum alloys and alloy combinations in thicknesses to 0.125 inch, as well as titanium in thicknesses to 0.056 inch. The explosively welded joints are less than one-half inch in width and apparently have no long length limitation. The ribbon explosive developed in this study contains very small quantities of explosive encased in a flexible thin lead sheath. The evaluation and demonstration of this welding technique was accomplished in three phases: evaluation and optimization of ten major explosive welding variables, the development of four weld joints, and an applicational analysis which included photomicrographs, pressure integrity tests, vacuum effects, and fabrication of some potentially useful structures in aluminum and titanium.
A vision-based weld quality evaluation system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barnett, R.J.; Cook, G.E.; Strauss, A.M.
1996-12-31
Inspection of the appearance of weld beads is an integral part of the overall welding process. Lack of satisfactory appearance in itself may be sufficient grounds for part rejection or the lack of satisfactory appearance may be used as an indirect indicator of more substantive problems such as poor fusion or subsurface cracks. In all cases the inspection process tends to be both time and labor intensive. The present research uses a video system and appropriate image capture and processing to determine the quality of the weld based upon surface appearance. This relative quality rating was compared to similar ratingsmore » performed by human inspectors and was found to give very good correlation. The system was implemented for the Gas Tungsten Arc Welding (GTAW) and Gas Metal Arc Welding (GMAW) processes.« less
Laser beam welding of new ultra-high strength and supra-ductile steels
NASA Astrophysics Data System (ADS)
Dahmen, Martin
2015-03-01
Ultra-high strength and supra-ductile are entering fields of new applications. Those materials are excellent candidates for modern light-weight construction and functional integration. As ultra-high strength steels the stainless martensitic grade 1.4034 and the bainitic steel UNS 53835 are investigated. For the supra-ductile steels stand two high austenitic steels with 18 and 28 % manganese. As there are no processing windows an approach from the metallurgical base on is required. Adjusting the weld microstructure the Q+P and the QT steels require weld heat treatment. The HSD steel is weldable without. Due to their applications the ultra-high strength steels are welded in as-rolled and strengthened condition. Also the reaction of the weld on hot stamping is reflected for the martensitic grades. The supra-ductile steels are welded as solution annealed and work hardened by 50%. The results show the general suitability for laser beam welding.
46 CFR 56.75-30 - Pipe joining details.
Code of Federal Regulations, 2010 CFR
2010-10-01
... be either of the socket or butt type. When butt joints are employed the edges to be joined shall be.... Circumferential joints may be either of the butt or socket type. Where butt joints are employed, the included... annular clearance of socket joints shall be held to small clearances which experience indicates is...
A Microprocessor Development System for the Intel 8748 Microcomputer.
1979-12-01
their ready availability, it was decided to build the system on a 4 x 6 Vector plugboard with a 44 pin connect- or and which was predrilled for wirewrap...8748, additional sockets were provided in a 4 socket mother board. These sockets accept the standard 44 pin Vector plugboard . It is recommended that
46 CFR 56.75-30 - Pipe joining details.
Code of Federal Regulations, 2014 CFR
2014-10-01
... be either of the socket or butt type. When butt joints are employed the edges to be joined shall be.... Circumferential joints may be either of the butt or socket type. Where butt joints are employed, the included... annular clearance of socket joints shall be held to small clearances which experience indicates is...
46 CFR 56.75-30 - Pipe joining details.
Code of Federal Regulations, 2013 CFR
2013-10-01
... be either of the socket or butt type. When butt joints are employed the edges to be joined shall be.... Circumferential joints may be either of the butt or socket type. Where butt joints are employed, the included... annular clearance of socket joints shall be held to small clearances which experience indicates is...
46 CFR 56.75-30 - Pipe joining details.
Code of Federal Regulations, 2012 CFR
2012-10-01
... be either of the socket or butt type. When butt joints are employed the edges to be joined shall be.... Circumferential joints may be either of the butt or socket type. Where butt joints are employed, the included... annular clearance of socket joints shall be held to small clearances which experience indicates is...
46 CFR 56.75-30 - Pipe joining details.
Code of Federal Regulations, 2011 CFR
2011-10-01
... be either of the socket or butt type. When butt joints are employed the edges to be joined shall be.... Circumferential joints may be either of the butt or socket type. Where butt joints are employed, the included... annular clearance of socket joints shall be held to small clearances which experience indicates is...
Development of socketed foundations for S3X5.7 posts.
DOT National Transportation Integrated Search
2015-04-01
The objective of this study was to develop a socketed foundation for use with the S3x5.7 (S76x8.5) weak : post. The design focused on cylindrical, reinforced concrete foundations with a steel tube placed in the center for : use as the socket. The fou...
Extraction socket sealing using palatal gingival grafts and resorbable collagen membranes.
Kim, Sang-Yun; Kim, Young-Kyun; Kim, Hyun-Suk; Yun, Pil-Young; Kim, Su-Gwan; Choi, Yong-Hun
2017-12-01
Socket sealing surgery is performed for the preservation of the form and volume of the soft tissue by covering the resulting socket with autogenous soft tissue graft or membrane barriers. This procedure is usually necessary to improve the esthetic results of the maxillary anterior or premolar areas. This study retrospectively investigated cases involving the open membrane technique or socket sealing surgery with a palatal gingival graft or collagen membrane where implant placement and bone grafting were performed immediately after tooth extraction. From January 2005 to December 2008, socket sealing surgery was performed in 24 patients, and 25 implants were placed. All implants were successful in the follow-up period. In the palatal gingival graft group, the mean marginal bone loss was 1.17 mm during the mean follow-up period of 81.0 months. In the collagen membrane group, the mean marginal bone loss was 1.23 mm during the mean follow-up period of 76.9 months. There was no significant difference between the two groups. Consequently, socket sealing surgery is effective at minimizing the loss of soft tissue and alveolar bone.
NASA Astrophysics Data System (ADS)
Santosh, R.; Das, G.; Kumar, S.; Singh, P. K.; Ghosh, M.
2018-03-01
The structural integrity of dissimilar metal welded (DMW) joint consisting of low-alloy steel and 304LN austenitic stainless steel was examined by evaluating mechanical properties and metallurgical characteristics. INCONEL 82 and 182 were used as buttering and filler materials, respectively. Experimental findings were substantiated through thermomechanical simulation of the weld. During simulation, the effect of thermal state and stress distribution was pondered based on the real-time nuclear power plant environment. The simulation results were co-related with mechanical and microstructural characteristics. Material properties were varied significantly at different fusion boundaries across the weld line and associated with complex microstructure. During in-situ deformation testing in a scanning electron microscope, failure occurred through the buttering material. This indicated that microstructure and material properties synergistically contributed to altering the strength of DMW joints. Simulation results also depicted that the stress was maximum within the buttering material and made its weakest zone across the welded joint during service exposure. Various factors for the failure of dissimilar metal weld were analyzed. It was found that the use of IN 82 alloy as the buttering material provided a significant improvement in the joint strength and became a promising material for the fabrication of DMW joint.
NASA Astrophysics Data System (ADS)
Santosh, R.; Das, G.; Kumar, S.; Singh, P. K.; Ghosh, M.
2018-06-01
The structural integrity of dissimilar metal welded (DMW) joint consisting of low-alloy steel and 304LN austenitic stainless steel was examined by evaluating mechanical properties and metallurgical characteristics. INCONEL 82 and 182 were used as buttering and filler materials, respectively. Experimental findings were substantiated through thermomechanical simulation of the weld. During simulation, the effect of thermal state and stress distribution was pondered based on the real-time nuclear power plant environment. The simulation results were co-related with mechanical and microstructural characteristics. Material properties were varied significantly at different fusion boundaries across the weld line and associated with complex microstructure. During in-situ deformation testing in a scanning electron microscope, failure occurred through the buttering material. This indicated that microstructure and material properties synergistically contributed to altering the strength of DMW joints. Simulation results also depicted that the stress was maximum within the buttering material and made its weakest zone across the welded joint during service exposure. Various factors for the failure of dissimilar metal weld were analyzed. It was found that the use of IN 82 alloy as the buttering material provided a significant improvement in the joint strength and became a promising material for the fabrication of DMW joint.
Development of a residuum/socket interface simulator for lower limb prosthetics.
McGrath, Michael Paul; Gao, Jianliang; Tang, Jinghua; Laszczak, Piotr; Jiang, Liudi; Bader, Dan; Moser, David; Zahedi, Saeed
2017-03-01
Mechanical coupling at the interface between lower limb residua and prosthetic sockets plays an important role in assessing socket fitting and tissue health. However, most research lab-based lower limb prosthetic simulators to-date have implemented a rigid socket coupling. This study describes the fabrication and implementation of a lower limb residuum/socket interface simulator, designed to reproduce the forces and moments present during the key loading phases of amputee walking. An artificial residuum made with model bones encased in silicone was used, mimicking the compliant mechanical loading of a real residuum/socket interface. A 6-degree-of-freedom load cell measured the overall kinetics, having previously been incorporated into an amputee's prosthesis to collect reference data. The developed simulator was compared to a setup where a rigid pylon replaced the artificial residuum. A maximum uniaxial load of 850 N was applied, comparable to the peak vertical ground reaction force component during amputee walking. Load cell outputs from both pylon and residuum setups were compared. During weight acceptance, when including the artificial residuum, compression decreased by 10%, while during push off, sagittal bending and anterior-posterior shear showed a 25% increase and 34% decrease, respectively. Such notable difference by including a compliant residuum further highlighted the need for such an interface simulator. Subsequently, the simulator was adjusted to produce key load cell outputs briefly aligning with those from amputee walking. Force sensing resistors were deployed at load bearing anatomic locations on the residuum/socket interface to measure pressures and were compared to those cited in the literature for similar locations. The development of such a novel simulator provides an objective adjunct, using commonly available mechanical test machines. It could potentially be used to provide further insight into socket design, fit and the complex load transfer mechanics at the residuum/socket interface, as well as to evaluate the structural performance of prostheses.
Improved Ball-and-Socket Docking Mechanism
NASA Technical Reports Server (NTRS)
Cloyd, Richard; Bryan, Tom
2004-01-01
A proposed docking mechanism would form a ball-and-socket joint in the docked condition. The mechanism could tolerate significant initial misalignment because it would include an alignment cone that would guide the ball into the socket. Like other ball-and-socket joints, the joint would have three rotational degrees of freedom. This docking mechanism would be a successor to the one described in Passive Capture Joint With Three Degrees of Freedom (MFS-31146), NASA Tech Briefs, Vol. 22, No. 7 (July 1998), page 65. It would contain most of the components of the prior mechanism, plus some additional components that would expand its capabilities.
Probe-And-Socket Fasteners For Robotic Assembly
NASA Technical Reports Server (NTRS)
Nyberg, Karen
1995-01-01
Self-alignment and simplicity of actuation make mechanism amenable to robotic assembly. Includes socket, mounted on structure at worksite, and probe, mounted on piece of equipment to be attached to structure at socket. Probe-and-socket mechanism used in conjunction with fixed target aiding in placement of end effector of robot during grasping, and with handle or handles on structure. Intended to enable robot to set up workstation in hostile environment. Workstation then used by astronaut, aquanaut, or other human, spending minimum time in environment. Human concentrates on performing quality work rather than on setting up equipment, with consequent reduction of risk.
El Chaar, Edgard; Oshman, Sarah; Cicero, Giuseppe; Castano, Alejandro; Dinoi, Cinzia; Soltani, Leila; Lee, Yoonjung Nicole
Localized ridge resorption, the consequence of socket collapse, following tooth extraction in the anterior maxilla can adversely affect esthetics, function, and future implant placement. Immediate grafting of extraction sockets may help preserve natural ridge contours, but a lack of available soft tissue can compromise the final esthetic outcome. The presented modified rotated palatal pedicle connective tissue flap is a useful technique for simultaneous soft tissue coverage and augmentation of grafted sockets to improve esthetic outcome. This article delineates its advantages through the presentation of a four-case series using this new technique.
Postoperative Complications of Dermis-Fat Autografts in the Anophthalmic Socket.
Starks, Victoria; Freitag, Suzanne K
2018-01-01
Reconstruction of the anophthalmic socket allows the use of an ocular prosthesis and rehabilitation of facial appearance. Dermis-fat grafting is one option in volume augmentation of the anophthalmic socket and presents unique benefits, including increased surface area within the socket and the ability to grow with pediatric patients. Postoperative complications of this procedure are relatively common. Minor complications, such as graft hirsutism, keratinization, and conjunctival cysts or granulomas, are managed easily by observation or simple intervention. Major complications, such as graft atrophy, infection, or ulceration, may prevent good prosthesis fit and may require return to the operating room.
NASA Technical Reports Server (NTRS)
Gambrell, S. C.; Karr, Gerald R.
1993-01-01
Previous work using Photostress on TIG welded, heat treated specimens of 2219-T87 parent material and 2319 weld material indicated that behavior of the joint can be highly irregular and non-uniform. Welded joints 1.40 inches thick exhibited a totally non-uniform behavior through the weld thickness with the 'wide' side of the weld being much more ductile than the 'narrow' side. It is believed that this difference in behavior through the weld is, in part, caused by procedures used when laying the weld bead. Joints similar to weldments in references 1 and 2 are an integral part of the aft skirt of the SRB of the shuttle. Since the ultimate safety factor for the lower portion of the weld is below the minimum required safety factor, a photostress analysis of this lower portion will be conducted in the vicinity of the weld. A test program using photostress will be conducted in accordance with the project planning document entitled 'Photostress Evaluation Requirements for AFT Skirt Test Article No. 4'.
Chang, Hao-Hueng; Wang, Yin-Lin; Chiang, Yu-Chih; Chen, Yen-Liang; Chuang, Yu-Horng; Tsai, Shang-Jye; Heish, Kuo-Huang; Lin, Feng-Huei; Lin, Chun-Pin
2014-01-01
A novel chitosan-γPGA polyelectrolyte complex hydrogel (C-PGA) has been developed and proven to be an effective dressing for wound healing. The purpose of this study was to evaluate if C-PGA could promote new bone formation in the alveolar socket following tooth extraction. An animal model was proposed using radiography and histomorphology simultaneously to analyze the symmetrical sections of Wistar rats. The upper incisors of Wistar rats were extracted and the extraction sockets were randomly treated with gelatin sponge, neat chitosan, C-PGA, or received no treatment. The extraction sockets of selected rats from each group were evaluated at 1, 2, 4, or 6 wk post-extraction. The results of radiography and histopathology indicated that the extraction sockets treated with C-PGA exhibited lamellar bone formation (6.5%) as early as 2 wk after the extraction was performed. Moreover, the degree of new bone formation was significantly higher (P < 0.05) in the extraction sockets treated with C-PGA at 6 wk post-extraction than that in the other study groups. In this study, we demonstrated that the proposed animal model involving symmetrical sections and simultaneous radiography and histomorphology evaluation is feasible. We also conclude that the novel C-PGA has great potential for new bone formation in the alveolar socket following tooth extraction. PMID:24658174
Yu, H J; Jia, P; Lv, Z; Qiu, L X
2017-04-01
The aim of this study was to analyze and compare the long-term clinical outcomes of mature third molar autotransplantation in surgically created sockets and fresh extraction sockets with regard to survival and functional success rates. A total of 65 third molars with completely formed roots were autotransplanted in 60 patients (average age 33.1 years). Thirty-six of the teeth were autotransplanted into surgically created sockets with or without guided bone regeneration (GBR; delayed autotransplantation), while 29 were autotransplanted into fresh extraction sockets (immediate autotransplantation; control group). All patients underwent annual clinical and radiographic examinations (average follow-up 9.9 years, range 7-13 years). The survival rates for the control, GBR, and no GBR groups were 93.1%, 95.2%, and 80.0%, respectively, with no significant differences among the groups. There were no statistically significant differences among the groups with regard to the frequency of inflammatory root resorption or root ankylosis. Age did not influence the clinical outcomes. These results suggest that the autotransplantation of third molars with completely formed roots is effective in both surgically created and fresh extraction sockets and provides a high long-term success rate if cases are selected and treated appropriately. Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
LaPrè, A K; Price, M A; Wedge, R D; Umberger, B R; Sup, Frank C
2018-04-01
Musculoskeletal modeling and marker-based motion capture techniques are commonly used to quantify the motions of body segments, and the forces acting on them during human gait. However, when these techniques are applied to analyze the gait of people with lower limb loss, the clinically relevant interaction between the residual limb and prosthesis socket is typically overlooked. It is known that there is considerable motion and loading at the residuum-socket interface, yet traditional gait analysis techniques do not account for these factors due to the inability to place tracking markers on the residual limb inside of the socket. In the present work, we used a global optimization technique and anatomical constraints to estimate the motion and loading at the residuum-socket interface as part of standard gait analysis procedures. We systematically evaluated a range of parameters related to the residuum-socket interface, such as the number of degrees of freedom, and determined the configuration that yields the best compromise between faithfully tracking experimental marker positions while yielding anatomically realistic residuum-socket kinematics and loads that agree with data from the literature. Application of the present model to gait analysis for people with lower limb loss will deepen our understanding of the biomechanics of walking with a prosthesis, which should facilitate the development of enhanced rehabilitation protocols and improved assistive devices. Copyright © 2017 John Wiley & Sons, Ltd.
Safari, Mohammad Reza; Meier, Margrit Regula
2015-01-01
This review is an attempt to untangle the complexity of transtibial prosthetic socket fit, determine the most important characteristic for a successful fitting, and perhaps find some indication of whether a particular prosthetic socket type might be best for a given situation. Further, it is intended to provide directions for future research. We followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and used medical subject headings and standard key words to search for articles in relevant databases. No restrictions were made on study design or type of outcome measure. From the obtained search results (n = 1,863), 35 articles were included. The relevant data were entered into a predefined data form that incorporated the Downs and Black risk of bias assessment checklist. Results for the qualitative outcomes (n = 19 articles) are synthesized. Total surface bearing sockets lead to greater activity levels and satisfaction in active persons with amputation, those with a traumatic cause of amputation, and younger persons with amputation than patellar tendon bearing sockets. Evidence on vacuum-assisted suction and hydrostatic sockets is inadequate, and further studies are much needed. To improve the scientific basis for prescription, comparison of and correlation between mechanical properties of interface material, socket designs, user characteristics, and outcome measures should be conducted and reported in future studies.
Mandour, Sameh S; Elmazar, Hesham M; Marey, Hatem M; Rahman, Ahmed K Abdel; Sakr, Rokia A
2016-12-01
To evaluate the use of intraoperative topical application of mitomycin C (MMC) for managing cases of recurrent socket contraction. A prospective comparative randomized study was carried out on 40 patients suffering from contracted sockets. They were randomly enrolled into 2 groups. Group A included 20 patients who had a surgery to treat contracted socket without augmentation with MMC. Group B patients had an MMC-augmented repair for the contracted socket. Patients were followed up over a period of 12 months for changes in inferior fornix (IF) depth and ability to retain the ocular prosthesis. At the end of the follow-up period, postoperative IF depth was significantly deeper in group B (with MMC) than in group A (without MMC). As well, 75% of the patients in group B could maintain the prosthetic eye shell, whereas only 35% of group A could maintain the prosthesis. This study shows that using intraoperative MMC (0.2 mg/mL) in contracted socket reconstruction plays a significant role in maintaining prosthetic eye. To the best of our knowledge, this study is the first to use MMC on a relatively large scale of patients with contracted socket. However, the follow-up period was relatively short and further work is required to verify the effect of MMC on a longer follow-up period.
Jaiswara, Chandresh; Srivastava, Vinay K; Dhiman, Neeraj
2016-01-01
Esthetics is a prime concern for a young lady. Any anomaly in the anterior tooth may create anxiety and depression. This anxiety and depression may hamper her married life and overall personality. This case report reveals an unerupted right central incisor situated in a strange position, creating space in the maxillary anterior region and giving an unesthetic appearance. Autotransplantation is a method of choice for a strangely positioned impacted central incisor in a new appropriate site. This method offers a new treatment option for some clinical situations if orthodontic approach is not possible. It permits tooth movement to a distant or the opposite side of the same dental arch as well as to the opposite jaw. This procedure also offers potential benefits of reestablishment of normal alveolar process development, esthetics, functions, and arch integrity. This procedure has the potential to become a viable alternative treatment plan for young patients of low socioeconomic status, allowing the reestablish-ment and restoration of a missing tooth and their functions. This article discusses methods of auto-reimplantation of a tooth in a fresh surgically prepared socket, its biological principle, and establishment of functions, esthetics, and phonetics. Jaiswara C, Srivastava VK, Dhiman N. Autotransplantation of a Strange Positioned Impacted Central Incisor in a surgically Prepared Socket: A Miracle Esthetic Concept. Int J Clin Pediatr Dent 2016;9(3):269-272.
Gas Shielding Technology for Welding and Brazing
NASA Technical Reports Server (NTRS)
Nunes, Arthur J.; Gradl, Paul R.
2012-01-01
Welding is a common method that allows two metallic materials to be joined together with high structural integrity. When joints need to be leak-tight, light-weight, or free of contaminant-trapping seams or surface asperities, welding tends to be specified. There are many welding techniques, each with its own advantages and disadvantages. Some of these techniques include Forge Welding, Gas Tungsten Arc Welding, Friction Stir Welding, and Laser Beam Welding to name a few. Whichever technique is used, the objective is a structural joint that meets the requirements of a particular component or assembly. A key practice in producing quality welds is the use of shielding gas. This article discusses various weld techniques, quality of the welds, and importance of shielding gas in each of those techniques. Metallic bonds, or joints, are produced when metals are put into intimate contact. In the solid-state "blacksmith welding" process, now called Forge Welding (FOW), the site to be joined is pounded into intimate contact. The surfaces to be joined usually need to be heated to make it easier to deform the metal. The surfaces are sprinkled with a flux to melt surface oxides and given a concave shape so that surface contamination can be squeezed out of the joint as the surfaces are pounded together; otherwise the surface contamination would be trapped in the joint and would weaken the weld. In solid-state welding processes surface oxides or other contamination are typically squeezed out of the joint in "flash."
21 CFR 888.3510 - Knee joint femorotibial metal/polymer constrained cemented prosthesis.
Code of Federal Regulations, 2012 CFR
2012-04-01
...-and-socket joint located between a stemmed femoral and a stemmed tibial component and a runner and track joint between each pair of femoral and tibial condyles. The ball-and-socket joint is composed of a...-molybdenum. The ball of the tibial component is held within the socket of the femoral component by the...
21 CFR 888.3510 - Knee joint femorotibial metal/polymer constrained cemented prosthesis.
Code of Federal Regulations, 2011 CFR
2011-04-01
...-and-socket joint located between a stemmed femoral and a stemmed tibial component and a runner and track joint between each pair of femoral and tibial condyles. The ball-and-socket joint is composed of a...-molybdenum. The ball of the tibial component is held within the socket of the femoral component by the...
Preliminary evaluation of hermetic JT/LJT/R P connector socket contact design
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baca, J.R.F.
1991-10-01
This report presents a precursory examination of a number of issues pertaining to socket contacts in hermetic connectors. The principal issues addressed are high-contact resistance and contact chatter (circuit discontinuities). Efforts examining the characteristics of the existing socket contact design, the possibility of connector/contact rework, quick-fix solutions, and contact redesigns are summarized.
21 CFR 888.3510 - Knee joint femorotibial metal/polymer constrained cemented prosthesis.
Code of Federal Regulations, 2013 CFR
2013-04-01
...-and-socket joint located between a stemmed femoral and a stemmed tibial component and a runner and track joint between each pair of femoral and tibial condyles. The ball-and-socket joint is composed of a...-molybdenum. The ball of the tibial component is held within the socket of the femoral component by the...
21 CFR 888.3510 - Knee joint femorotibial metal/polymer constrained cemented prosthesis.
Code of Federal Regulations, 2014 CFR
2014-04-01
...-and-socket joint located between a stemmed femoral and a stemmed tibial component and a runner and track joint between each pair of femoral and tibial condyles. The ball-and-socket joint is composed of a...-molybdenum. The ball of the tibial component is held within the socket of the femoral component by the...
[Study on the arc spectral information for welding quality diagnosis].
Li, Zhi-Yong; Gu, Xiao-Yan; Li, Huan; Yang, Li-Jun
2009-03-01
Through collecting the spectral signals of TIG and MIG welding arc with spectrometer, the arc light radiations were analyzed based on the basic theory of plasma physics. The radiation of welding arc distributes over a broad range of frequency, from infrared to ultraviolet. The arc spectrum is composed of line spectra and continuous spectra. Due to the variation of metal density in the welding arc, there is great difference between the welding arc spectra of TIG and MIG in both their intensity and distribution. The MIG welding arc provides more line spectra of metal and the intensity of radiation is greater than TIG. The arc spectrum of TIG welding is stable during the welding process, disturbance factors that cause the spectral variations can be reflected by the spectral line related to the corresponding element entering the welding arc. The arc spectrum of MIG welding will fluctuate severely due to droplet transfer, which produces "noise" in the line spectrum aggregation zone. So for MIG welding, the spectral zone lacking spectral line is suitable for welding quality diagnosis. According to the characteristic of TIG and MIG, special spectral zones were selected for welding quality diagnosis. For TIG welding, the selected zone is in ultraviolet zone (230-300 nm). For MIG welding, the selected zone is in visible zone (570-590 nm). With the basic theory provided for welding quality diagnosis, the integral intensity of spectral signal in the selected zone of welding process with disturbing factor was studied to prove the theory. The results show that the welding quality and disturbance factors can be diagnosed with good signal to noise ratio in the selected spectral zone compared with signal in other spectral zone. The spectral signal can be used for real-time diagnosis of the welding quality.
Prevention and treatment of dry socket.
Dodson, Tom
2013-03-01
Cochrane Oral Health Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), Medline and Embase databases were searched together with reference lists of identified articles. Topic experts and organisations were also contacted. Only randomised controlled trials were considered and there were no restrictions regarding language or date of publication. Data abstraction and risk of bias assessment were conducted in duplicate and Cochrane statistical guidelines were followed. The GRADE tool was used to assess the quality of the body of evidence. Twenty-one trials with 2570 participants were included. Eighteen trials (2376 participants) related to prevention and three to treatment (194 participants). Six studies were at high risk of bias, 14 of unclear risk and one study at low risk. There was moderate evidence (four trials, 750 participants) that chlorhexidine mouthrinses (0.12% and 0.2% concentrations) both before and after extraction(s) prevented approximately 42% of dry socket(s) with a RR of 0.58 (95% CI 0.43 to 0.78; P < 0.001). The number of patients needed to be treated (0.12% and 0.2%) with chlorhexidine rinse to prevent one patient having dry socket (NNT) was 232 (95% CI 176 to 417), 47 (95% CI 35 to 84) and 8 (95% CI 6 to 14) at prevalences of dry socket of 1%, 5% and 30% respectively. Thee was moderate evidence (two trials, in 133 participants) that placing chlorhexidine gel (0.2%) after extractions prevented approximately 58% of dry socket(s) with a RR of 0.42 (95% CI 0.21 to 0.87; P = 0.02) with NNT of 173 (95% CI 127 to 770), 35 (95% CI 25 to 154) and 6 (95% CI 5 to 26) at prevalences of dry socket of 1%, 5% and 30% respectively. There was insufficient evidence to determine the effects of other intrasocket preventive interventions or interventions to treat dry socket. There is some evidence that rinsing with chlorhexidine (0.12% and 0.2%) or placing chlorhexidine gel (0.2%) in the sockets of extracted teeth, provides a benefit in preventing dry socket. There was insufficient evidence to determine the effects of the other 10 preventative interventions each evaluated in single studies. There was insufficient evidence to determine the effects of any of the interventions to treat dry socket. The present review found some evidence for the association of minor adverse reactions with use of 0.12%, 0.2% and 2% chlorhexidine mouthrinses, though most studies were not designed to detect the presence of hypersensitivity reactions to mouthwash as part of the study protocol. No adverse events were reported in relation to the use of 0.2% chlorhexidine gel placed directly into a socket (though previous allergy to chlorhexidine was an exclusion criterion in these trials). In view of recent reports in the UK of two cases of serious adverse events associated with irrigation of dry socket with chlorhexidine mouthrinse, it is recommended that all members of the dental team prescribing chlorhexidine products are aware of the potential for both minor and serious adverse side effects. It is beyond the scope of this review to describe and detail The Cochrane Collaboration. The reader can seek out more information at http://www.cochrane.org/. In brief, a systematic review supported and published by the Cochrane group represents the gold standard to support clinical decision-making.
Jee, Jeong-Hyun; Lee, Wan; Lee, Byung Do
2010-08-01
Many dental patients take bisphosphonates to reduce the risk of hip and vertebral fractures. In vivo micro-computed tomography (micro-CT) was used to examine the longitudinal inhibitory effect of alendronate on the healing of extraction sockets in ovariectomized rats. Twenty 5-week-old Sprague-Dawley rats were assigned randomly to 1 of 3 groups: sham-operated (n = 5), and 2 ovariectomized (OVX) groups: saline treated (0.1 mL/100 g/d, n = 7) and alendronate treated (1 mg/kg/d, n = 8). Before micro-CT scanning, the left maxillary first molars of the rats were extracted. In vivo micro-CT (spatial resolution 50 x 50 mum) of the jaw was performed at baseline and at 2-week intervals for 6 weeks. Alveolar-bone radiographic densities and dimensions were analyzed with repeated measures analysis of variance. The bony healing patterns of the extraction sockets were also evaluated in each group. The radiographic socket densities of the sham-treated and OVX-alendronate groups significantly increased during the first 4 weeks after extraction (P < .05). At 2 weeks, the radiographic densities of the sockets in the OVX-saline group increased, but the increase was significantly lower than for the other groups at 4 weeks (P < .05). Newly formed bone was identified in the extraction sockets in all groups 2 to 6 weeks after extraction. There was a significant loss of alveolar ridge height at the second week postextraction compared with baseline, and at the fourth week compared with the second week (P < .05) except in the alendronate group. Alendronate appears to promote the healing of extraction sockets in estrogen-deficient rats and helps resist the loss of alveolar bone adjacent to extraction sockets. Copyright 2010 Mosby, Inc. All rights reserved.
Kobayashi, Toshiki; Arabian, Adam K; Orendurff, Michael S; Rosenbaum-Chou, Teri G; Boone, David A
2014-01-01
Energy storage and return feet are designed for active amputees. However, little is known about the socket reaction moments in transtibial prostheses with energy storage and return feet. The aim of this study was to investigate the effect of alignment changes on the socket reaction moments during gait while using the energy storage and return feet. A Smart Pyramid™ was used to measure the socket reaction moments in 10 subjects with transtibial prostheses while walking under 25 alignment conditions, including a nominal alignment (as defined by conventional clinical methods), as well as angle malalignments of 2°, 4° and 6° (flexion, extension, abduction, and adduction) and translation malalignments of 5mm, 10mm and 15mm (anterior, posterior, lateral, and medial) referenced from the nominal alignment. The socket reaction moments of the nominal alignment were compared with each malalignment. Both coronal and sagittal alignment changes demonstrated systematic effects on the socket reaction moments. In the sagittal plane, angle and translation alignment changes demonstrated significant differences (P<0.05) in the minimum moment, the moment at 45% of stance and the maximum moment for some comparisons. In the coronal plane, angle and translation alignment changes demonstrated significant differences (P<0.05) in the moment at 30% and 75% of stance for all comparisons. The alignment may have systematic effects on the socket reaction moments in transtibial prostheses with energy storage and return feet. The socket reaction moments could potentially be a useful biomechanical parameter to evaluate the alignment of the transtibial prostheses. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
2001-01-01
A new self-adjusting, retractable pin tool for friction stir welding is now used in the manufacturing of components for NASA Space Shuttles. Friction stir welding is a process that makes straight-line welds without bringing the parent material to a liquid state. This is accomplished through high-speed rotation, which generates frictional heat between the welding tool and the piece being welded. This heat causes the material to soften to the point of plasticity without allowing it to melt. The plasticized material is then transferred from the front edge of the welding tool to the trail edge, where it joins the pieces being welded. However, a major flaw of this method is its reliance on a single-piece pin tool. The weld is left unfinished and a hole remains where the pin was inserted. The hole must be covered with a rivet in order to preserve the integrity of the weld. The NASA-developed pin tool, however, eliminates the need for this finishing step, as its retraction allows continuous rewelding at lesser depths, until the hole is completely closed. With this NASA technology, welding of higher strength alloys, as well as non-planer and variable thickness structures can be achieved.
Critical Initial Flaw Size Analysis
NASA Technical Reports Server (NTRS)
Dawicke, David S.; Raju, Ivatury S.; Cheston, Derrick J.
2008-01-01
An independent assessment was conducted to determine the critical initial flaw size (CIFS) for the flange-to-skin weld in the Ares I-X Upper Stage Simulator (USS). The USS consists of several "tuna can" segments that are approximately 216 inches in diameter, 115 inches tall, and 0.5 inches thick. A 6 inch wide by 1 inch thick flange is welded to the skin and is used to fasten adjacent tuna cans. A schematic of a "tuna can" and the location of the flange-to-skin weld are shown in Figure 1. Gussets (shown in yellow in Figure 1) are welded to the skin and flange every 10 degrees around the circumference of the "tuna can". The flange-to-skin weld is a flux core butt weld with a fillet weld on the inside surface, as illustrated in Figure 2. The welding process may create loss of fusion defects in the weld that could develop into fatigue cracks and jeopardize the structural integrity of the Ares I-X vehicle. The CIFS analysis was conducted to determine the largest crack in the weld region that will not grow to failure within 4 lifetimes, as specified by NASA standard 5001 & 5019 [1].
Friction Stir Welding: Standards and Specifications in Today's U.S. Manufacturing and Fabrication
NASA Technical Reports Server (NTRS)
Ding, Robert Jeffrey
2008-01-01
New welding and technology advancements are reflected in the friction stir welding (FSW) specifications used in the manufacturing sector. A lack of publicly available specifications as one of the reasons that the FSW process has not propagate through the manufacturing sectors. FSW specifications are an integral supporting document to the legal agreement written between two entities for deliverable items. Understanding the process and supporting specifications is essential for a successful FSW manufacturing operation. This viewgraph presentation provides an overview of current FSW standards in the industry and discusses elements common to weld specifications.
Cooled electronic system with thermal spreaders coupling electronics cards to cold rails
Chainer, Timothy J; Gaynes, Michael A; Graybill, David P; Iyengar, Madhusudan K; Kamath, Vinod; Kochuparambil, Bejoy J; Schmidt, Roger R; Schultz, Mark D; Simco, Daniel P; Steinke, Mark E
2013-07-23
Liquid-cooled electronic systems are provided which include an electronic assembly having an electronics card and a socket with a latch at one end. The latch facilitates securing of the card within the socket or removal of the card from the socket. A liquid-cooled cold rail is disposed at the one end of the socket, and a thermal spreader couples the electronics card to the cold rail. The thermal spreader includes first and second thermal transfer plates coupled to first and second surfaces on opposite sides of the card, and thermally conductive extensions extending from end edges of the plates, which couple the respective transfer plates to the liquid-cooled cold rail. The thermally conductive extensions are disposed to the sides of the latch, and the card is securable within or removable from the socket using the latch without removing the cold rail or the thermal spreader.
Mourits, Daphne L; Remmers, Jelmer S; Tan, Stevie H; Moll, Annette C; Hartong, Dyonne T
2018-04-03
To introduce a novel technique to design individually customized conformers for postenucleation sockets with dermis fat implants. We use a 3-dimensional scan of the frontal face/orbit and eyelid contour to design an individualized conformer. This polymethylmetacrylate printed conformer is adapted to patients' socket, palpebral fissures, horizontal eyelid aperture, curvature of the eyelids, and mean diameter of patients' contralateral eye. Sutures through holes in the inferior part of the conformer and in the extension can be placed to fixate the conformer and anchor fornix deepening sutures. A correct fitting conformer can be printed and attached to the socket and eyelids. The shape of this conformer can be used subsequently postsurgically to design the ocular prosthesis. Presurgical planning is important to anticipate for a functional socket to adequately fit an artificial eye. The presented technique using 3-dimensional imaging, designing, and printing promises to prevent conformer extrusion and forniceal shortening.
Conservative Socket Regeneration with Buccal Wall Defect Using Guided Tissue.
Al-Juboori, Mohammed Jasim
2016-01-01
Progressive alveolar bone resorption after tooth extraction may lead to surgical and prosthetic-driven difficulties, especially when deciding to use a dental implant to replace the extracted tooth. This case report discusses an irreparable lower left second premolar tooth with a periodontal lesion on the buccal side. A preservative tooth extraction was performed. Then, the socket was grafted with bovine bone, a collagen membrane was placed between the buccal bone and the attached gingiva, covering the bone dehiscence buccally, and the socket without a flap was raised. After a 6-month healing period, there was minimal socket width resorption and a shallow buccal vestibule. The implant was placed with high primary stability and sufficient buccal plate thickness. In conclusion, this guided tissue regeneration technique can minimize alveolar bone resorption in a socket with buccal dehiscence, but technical difficulties and shallowing of the buccal vestibule still exist.
Aggarwal, Himanshi; Singh, Saumyendra V; Kumar, Pradeep; Kumar Singh, Arun
2015-06-01
One of the most common tumors of the eye diagnosed in childhood is retinoblastoma, which mandates enucleation with adjunctive chemotherapy and radiotherapy to save the patient's life. The most common late enucleation complication is post-enucleation socket syndrome (PESS), which poses a management dilemma for the prosthodontist and surgeon, along with being a major esthetic concern for the patient. The reconstruction of such sockets is complex. The purpose of this clinical report is to describe the rehabilitation of such a pediatric patient with severe PESS. The patient was successfully rehabilitated by presurgical conformer therapy, socket reconstruction surgery with non-meshed intermediate split thickness skin graft (STSG)/Blair-Brown graft, and postsurgical conformer stent. This was followed by fabrication of a custom ocular prosthesis, to achieve favorable functional, physical, and psychological effects. © 2014 by the American College of Prosthodontists.
8-year survivorship analysis and subjective results of 687 primary Balgrist hip sockets.
Echtler, B; Jacob, H A; Houweling, M; Hersche, O
1999-09-01
The Balgrist hip socket consists of an outer split ring in the form of a truncated cone, made of titanium, which is expanded by a tapered HDPE insert during implantation, thus ensuring firm primary press-fit and the possibility of retightening in the postoperative remodelling phase. Between November 1987 and October 1996, 687 primary Balgrist hip sockets were implanted in 555 patients. Five hundred and thirty-seven patients were investigated. Of these patients, 71.1% never had pain in the operated hip, 88.1% had no problems putting on their shoes, 76.2% were able to walk one or more hours. Furthermore, 91.7% are very or mostly content with the postoperative result. Nineteen hip sockets had to be revised until April 1997. With a 92.1% Kaplan-Meier survivorship rate after 8 years the Balgrist hip socket ranks among the most successful noncemented acetabular components.
Simpson, G; Fisher, C; Wright, D K
2001-01-01
Continuing earlier studies into the relationship between the residual limb, liner and socket in transtibial amputees, we describe a geometrically accurate non-linear model simulating the donning of a liner and then a socket. The socket is rigid and rectified and the liner is a polyurethane geltype which is accurately described using non-linear (Mooney-Rivlin) material properties. The soft tissue of the residual limb is modelled as homogeneous, non-linear and hyperelastic and the bone structure within the residual limb is taken as rigid. The work gives an indication of how the stress induced by the process of donning the rigid socket is redistributed by the liner. Ultimately we hope to understand how the liner design might be modified to reduce discomfort. The ANSYS finite element code, version 5.6 is used.
Technology of welding aluminum alloys-II
NASA Technical Reports Server (NTRS)
1978-01-01
Step-by-step procedures were developed for high integrity manual and machine welding of aluminum alloys. Detailed instructions are given for each step with tables and graphs to specify materials and dimensions. Throughout work sequence, processing procedure designates manufacturing verification points and inspection points.
Phase-field simulation of weld solidification microstructure in an Al Cu alloy
NASA Astrophysics Data System (ADS)
Farzadi, A.; Do-Quang, M.; Serajzadeh, S.; Kokabi, A. H.; Amberg, G.
2008-09-01
Since the mechanical properties and the integrity of the weld metal depend on the solidification behaviour and the resulting microstructural characteristics, understanding weld pool solidification is of importance to engineers and scientists. Thermal and fluid flow conditions affect the weld pool geometry and solidification parameters. During solidification of the weld pool, a columnar grain structure develops in the weld metal. Prediction of the formation of the microstructure during welding may be an important and supporting factor for technology optimization. Nowadays, increasing computing power allows direct simulations of the dendritic and cell morphology of columnar grains in the molten zone for specific temperature conditions. In this study, the solidification microstructures of the weld pool at different locations along the fusion boundary are simulated during gas tungsten arc welding of Al-3wt%Cu alloy using the phase-field model for the directional solidification of dilute binary alloys. A macroscopic heat transfer and fluid flow model was developed to assess the solidification parameters, notably the temperature gradient and solidification growth rate. The effect of the welding speed is investigated. Computer simulations of the solidification conditions and the formation of a cellular morphology during the directional solidification in gas tungsten arc welding are described. Moreover, the simulation results are compared with existing theoretical models and experimental findings.
Code of Federal Regulations, 2010 CFR
2010-01-01
... with ceiling fan light kits that have medium screw base sockets shall conform to the requirements... testing pin-based fluorescent lamps packaged with ceiling fan light kits that have pin-based sockets shall... base sockets, measure the efficacy, expressed in lumens per watt, in accordance with the test...
NASA Technical Reports Server (NTRS)
Aperlo, P. J. A.; Buck, P. A.; Weldon, V. A.
1981-01-01
In ball and socket joint where electrical insulator such as polytetrafluoroethylene is used as line to minimize friction, good electrical contact across joint may be needed for lightning protection or to prevent static-charge build-up. Electrical contact is maintained by ring of spring-loaded fingers mounted in socket. It may be useful in industry for cranes, trailers, and other applications requiring ball and socket joint.
Carbon nanotubes functionalized with sodium hyaluronate restore bone repair in diabetic rat sockets.
Sá, M A; Andrade, V B; Mendes, R M; Caliari, M V; Ladeira, L O; Silva, E E; Silva, G A B; Corrêa-Júnior, J D; Ferreira, A J
2013-07-01
We evaluated the effects of sodium hyaluronate (HY) and carbon nanotubes functionalized with HY (HY-CNT) on bone repair in the tooth sockets of diabetic rats. Diabetes was induced by streptozotocin (50 mg kg(-1) i.v.), and the sockets were divided into normal control, diabetic control, diabetic treated with HY (1%), and diabetic treated with HY-CNT (100 μg ml(-1)) groups. The sockets were analyzed according to the percentage of bone formation and the number of cell nuclei. The percentage of bone trabeculae was lower in diabetic control animals (11.16 ± 5.10% vs 41.92 ± 6.34% in normal animals) after 14 days. Treating diabetic animals with HY or HY-CNT significantly increased the percentage of neoformed trabeculae (HY: 29.43 ± 3.29%; HY-CNT: 36.90 ± 3.07%). Moreover, the sockets of diabetic animals had an increased number of cell nuclei and HY or HY-CNT reduced this parameter. Our results indicate that HY and HY-CNT restore bone repair in the tooth sockets of diabetic rats, suggesting that these biomaterials are potential adjuvant therapies for the management of diabetes. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Bone implant sockets made using three different procedures: a stability study in dogs
Campo, Julián
2012-01-01
Objective: This study compared the effects of three different methods of preparing bone implant sockets (drilling, osteotomes, and piezoelectric device) on osseointegration using resonance frequency analysis (RFA). Study Design: An experimental prospective study was designed. Material and Methods: Ten adult beagle dogs were studied. After 5 weeks, 23 out of 28 initially placed implants in the iliac crest were evaluated, comparing these three different procedures of bone implant socket. Student’s t-test (paired, two-tailed) was used to reveal differences among the three groups at each time point (SPSS 16.0, IL, USA). Results: After a 5-week healing period, the implants placed in sockets that were made using an osteotome or piezoelectric device were slightly more stable than those made by drilling. Reduced mechanical and heat injury to the bone is beneficial for maintaining and improving stability during the critical early healing period. Conclusion: Using RFA, there was evidence of a slight increase in implant stability in the iliac crest after 5 weeks of healing when the implant socket was made using a piezoelectric device or expansion procedure as compare with the drilling method. Key words:Bone implant sockets, drilling, osteotomes, piezoelectric, resonance frequency analysis, stability. PMID:24558558
Al-Fakih, Ebrahim A.; Abu Osman, Noor Azuan; Eshraghi, Arezoo; Adikan, Faisal Rafiq Mahamd
2013-01-01
This study presents the first investigation into the capability of fiber Bragg grating (FBG) sensors to measure interface pressure between the stump and the prosthetic sockets of a trans-tibial amputee. FBG element(s) were recoated with and embedded in a thin layer of epoxy material to form a sensing pad, which was in turn embedded in a silicone polymer material to form a pressure sensor. The sensor was tested in real time by inserting a heavy-duty balloon into the socket and inflating it by using an air compressor. This test was conducted to examine the sensitivity and repeatability of the sensor when subjected to pressure from the stump of the trans-tibial amputee and to mimic the actual environment of the amputee's Patellar Tendon (PT) bar. The sensor exhibited a sensitivity of 127 pm/N and a maximum FSO hysteresis of around ∼0.09 in real-time operation. Very good reliability was achieved when the sensor was utilized for in situ measurements. This study may lead to smart FBG-based amputee stump/socket structures for pressure monitoring in amputee socket systems, which will result in better-designed prosthetic sockets that ensure improved patient satisfaction. PMID:23941909
Al-Fakih, Ebrahim A; Osman, Noor Azuan Abu; Eshraghi, Arezoo; Adikan, Faisal Rafiq Mahamd
2013-08-12
This study presents the first investigation into the capability of fiber Bragg grating (FBG) sensors to measure interface pressure between the stump and the prosthetic sockets of a trans-tibial amputee. FBG element(s) were recoated with and embedded in a thin layer of epoxy material to form a sensing pad, which was in turn embedded in a silicone polymer material to form a pressure sensor. The sensor was tested in real time by inserting a heavy-duty balloon into the socket and inflating it by using an air compressor. This test was conducted to examine the sensitivity and repeatability of the sensor when subjected to pressure from the stump of the trans-tibial amputee and to mimic the actual environment of the amputee's Patellar Tendon (PT) bar. The sensor exhibited a sensitivity of 127 pm/N and a maximum FSO hysteresis of around ~0.09 in real-time operation. Very good reliability was achieved when the sensor was utilized for in situ measurements. This study may lead to smart FBG-based amputee stump/socket structures for pressure monitoring in amputee socket systems, which will result in better-designed prosthetic sockets that ensure improved patient satisfaction.
Piezoelectric Bimorphs' Characteristics as In-Socket Sensors for Transfemoral Amputees
El-Sayed, Amr M.; Hamzaid, Nur Azah; Osman, Noor Azuan Abu
2014-01-01
Alternative sensory systems for the development of prosthetic knees are being increasingly highlighted nowadays, due to the rapid advancements in the field of lower limb prosthetics. This study presents the use of piezoelectric bimorphs as in-socket sensors for transfemoral amputees. An Instron machine was used in the calibration procedure and the corresponding output data were further analyzed to determine the static and dynamic characteristics of the piezoelectric bimorph. The piezoelectric bimorph showed appropriate static operating range, repeatability, hysteresis, and frequency response for application in lower prosthesis, with a force range of 0–100 N. To further validate this finding, an experiment was conducted with a single transfemoral amputee subject to measure the stump/socket pressure using the piezoelectric bimorph embedded inside the socket. The results showed that a maximum interface pressure of about 27 kPa occurred at the anterior proximal site compared to the anterior distal and posterior sites, consistent with values published in other studies. This paper highlighted the capacity of piezoelectric bimorphs to perform as in-socket sensors for transfemoral amputees. However, further experiments are recommended to be conducted with different amputees with different socket types. PMID:25513823
Bi, Xiaoping; Fan, Xianqun; Zhou, Huifang; Shi, Wodong; Xiao, Caiwen; Lin, Min; Li, Zhenkang
2011-05-01
Retinoblastoma is a common malignant intraocular tumor in childhood, and most patients require enucleation or exenteration even with irradiation. Severe anophthalmic orbits and atresic eye sockets are not rare. We conducted a retrospective study to evaluate the results of surgical management of reconstruction of severe anophthalmic orbits and atresic eye sockets with vascular anastomosed free dorsalis pedis flap transplantation. There were 5 patients (5 eyes) who underwent reconstructive surgery of severe anophthalmic orbits and atresic eye sockets after enucleation and irradiation of retinoblastoma in our hospital during the 3 years. All patients had enucleation and irradiation immediately after the retinoblastoma was diagnosed and had never worn artificial eyes because of the atresic eye sockets. Vascular anastomosed free dorsalis pedis flaps, whose dimensions were typically 6.5 × 5.5 cm(2), were transplanted to reconstruct the severe anophthalmic orbits and atresic eye sockets. The donor sites were covered by free abdominal skin flaps. All the vascular anastomosed free dorsalis pedis flaps were valid after more than 6 months of follow-up. And then all the 5 patients underwent secondary autogenous dermal fat implantation to augment the supraorbital area depression. After the 2-stage reconstruction surgery, the dimensions of the eye sockets were adequate, and all patients were able to wear their prosthesis and had a satisfactory cosmetic result. Implantation of alloplastic materials is not recommended because of insufficient blood supply of the irradiated orbital area.
Evaluation of osteoblastic activity in extraction sockets treated with platelet-rich fibrin.
Baslarli, Ozgur; Tumer, Celal; Ugur, Omer; Vatankulu, Betul
2015-01-01
The aim of this study was to determine whether the use of platelet rich fibrin (PRF) improved the healing of extraction sockets. A total of 20 patients with bilateral soft tissue impacted mandibular third molars were included in this study. The left and right third molars were extracted during the same session. Subsequently, the PRF membrane was randomly administered to one of the extraction sockets, whereas the contralateral sockets were left without treatment. On postoperative 30. and 90. days, panoramic images and bone scintigrams were taken to evaluate the bone healing between PRF-treated and non-PRF-treated sockets. Also, periodontal evaluation was performed in the same control sessions. Dependent group t test for paired samples was used for statistical analysis. The average increase in technetium-99m methylene diphosphonate uptake as an indication of enhanced bone healing did not differ significantly between PRF-treated and non-PRF-treated sockets 30 and 90 days postoperatively. Radio-opacity that can show the bone healing on panoramic images were measured by Image J programme and they did not differ significantly. Also periodontal values did not differ significantly. PRF might not lead to enhanced bone healing in impacted mandibular third molar extraction sockets 30 and 90 days after surgery. It is thought that PRF has the potential characteristics of an autologous fibrin matrix and can accelerate the healing. To better understand the effects of PRF on healing, further research is warranted with larger sample sizes.
Alveolar socket preservation with demineralised bovine bone mineral and a collagen matrix
2017-01-01
Purpose The aim of the present study was to evaluate the healing of post-extraction sockets following alveolar ridge preservation clinically, radiologically, and histologically. Methods Overall, 7 extraction sockets in 7 patients were grafted with demineralised bovine bone mineral and covered with a porcine-derived non-crosslinked collagen matrix (CM). Soft tissue healing was clinically evaluated on the basis of a specific healing index. Horizontal and vertical ridge dimensional changes were assessed clinically and radiographically at baseline and 6 months after implant placement. For histological and histomorphometric analysis, bone biopsies were harvested from the augmented sites during implant surgery 6 months after the socket preservation procedure. Results Clinically, healing proceeded uneventfully in all the sockets. A trend towards reduced horizontal and vertical socket dimensions was observed from baseline to the final examination. The mean width and height of resorption were 1.21 mm (P=0.005) and 0.46 mm (P=0.004), respectively. Histologically, residual xenograft particles (31.97%±3.52%) were surrounded by either newly formed bone (16.02%±7.06%) or connective tissue (50.67%±8.42%) without fibrous encapsulation. The CM underwent a physiological substitution process in favour of well-vascularised collagen-rich connective tissue. Conclusions Socket preservation using demineralised bovine bone mineral in combination with CM provided stable dimensional changes of the alveolar ridge associated with good re-epithelialisation of the soft tissues during a 6-month healing period. PMID:28861284
Madan, Rohit; Mohan, Ranjana; Bains, Vivek K; Gupta, Vivek; Singh, G P; Madan, Mani
2014-01-01
The aim of this study was to evaluate the extraction socket healing and dimensional changes following alveolar ridge preservation using polylactide and polyglycolide (PLA-PGA) sponge. Fifteen patients were selected for alveolar socket preservation immediately following tooth extraction. Monoradicular maxillary and mandibular teeth were evaluated. The selected sockets had intact sockets walls with a minimum of 7 mm of residual alveolar bone height. The test sites were thoroughly debrided and grafted with PLA-PGA sponge, while the control sites underwent natural healing. Computed tomography (CT) measurements were taken at baseline and 6 months. After 6 months of healing, final CT measurements were performed, and trephine core biopsy specimens were obtained for histologic analysis. Implants were placed immediately after biopsy harvesting. All subjects completed the study, and all sites healed without adverse events and allowed for implant placement. The mean difference in socket height, width, and density after 6 months was statistically significantly higher in the test sites compared with control sites. Clinical measurement at the midbuccal site of the alveolar socket showed a mean loss of 2.45 ± 0.67 mm in the control group, compared with a mean gain of 1.28 ± 0.58 mm in the test group. All test sites showed minimal ridge alterations, and statistically significant differences were observed between the test and control sites with respect to bone composition and horizontal and vertical bone loss, indicating that PLA-PGA sponge is suitable for alveolar ridge preservation.
NASA Astrophysics Data System (ADS)
Mirakhorli, Fatemeh; Cao, Xinjin; Pham, Xuan-Tan; Wanjara, Priti; Fihey, Jean-Luc
2016-07-01
Cast CA6NM martensitic stainless steel plates, 10 mm in thickness, were welded using hybrid laser-arc welding. The effect of different welding speeds on the as-welded joint integrity was characterized in terms of the weld bead geometry, defects, microstructure, hardness, ultimate tensile strength, and impact energy. Significant defects such as porosity, root humping, underfill, and excessive penetration were observed at a low welding speed (0.5 m/min). However, the underfill depth and excessive penetration in the joints manufactured at welding speeds above 0.75 m/min met the specifications of ISO 12932. Characterization of the as-welded microstructure revealed untempered martensite and residual delta ferrite dispersed at prior-austenite grain boundaries in the fusion zone. In addition, four different heat-affected zones in the weldments were differentiated through hardness mapping and inference from the Fe-Cr-Ni ternary phase diagram. The tensile fracture occurred in the base metal for all the samples and fractographic analysis showed that the crack path is within the martensite matrix, along primary delta ferrite-martensite interfaces and within the primary delta ferrite. Additionally, Charpy impact testing demonstrated slightly higher fracture energy values and deeper dimples on the fracture surface of the welds manufactured at higher welding speeds due to grain refinement and/or lower porosity.
Su, Chun; Zhou, Jianzhong; Meng, Xiankai; Huang, Shu
2016-09-26
As a new treatment process after welding, the process parameters of laser shock peening (LSP) in dynamic strain aging (DSA) temperature regimes can be precisely controlled, and the process is a non-contact one. The effects of LSP at elevated temperatures on the distribution of the surface residual stress of AA6061-T6 welded joints were investigated by using X-ray diffraction technology with the sin² ϕ method and Abaqus software. The fatigue life of the welded joints was estimated by performing tensile fatigue tests. The microstructural evolution in surface and fatigue fractures of the welded joints was presented by means of surface integrity and fracture surface testing. In the DSA temperature regime of AA6061-T6 welded joints, the residual compressive stress was distributed more stably than that of LSP at room temperature. The thermal corrosion resistance and fatigue properties of the welded joints were also improved. The experimental results and numerical analysis were in mutual agreement.
Su, Chun; Zhou, Jianzhong; Meng, Xiankai; Huang, Shu
2016-01-01
As a new treatment process after welding, the process parameters of laser shock peening (LSP) in dynamic strain aging (DSA) temperature regimes can be precisely controlled, and the process is a non-contact one. The effects of LSP at elevated temperatures on the distribution of the surface residual stress of AA6061-T6 welded joints were investigated by using X-ray diffraction technology with the sin2ϕ method and Abaqus software. The fatigue life of the welded joints was estimated by performing tensile fatigue tests. The microstructural evolution in surface and fatigue fractures of the welded joints was presented by means of surface integrity and fracture surface testing. In the DSA temperature regime of AA6061-T6 welded joints, the residual compressive stress was distributed more stably than that of LSP at room temperature. The thermal corrosion resistance and fatigue properties of the welded joints were also improved. The experimental results and numerical analysis were in mutual agreement. PMID:28773920
NASA Astrophysics Data System (ADS)
Pepe, Fabrizio; Corradino, Marta; Parrino, Nicolò; Besio, Giovanni; Presti, Valeria Lo; Renda, Pietro; Calcagnile, Lucio; Quarta, Gianluca; Sulli, Attilio; Antonioli, Fabrizio
2018-02-01
Boulders are frequently dislodged from rock platforms, transported and deposited along coastal zones by high-magnitude storm waves or tsunamis. Their size and shape are often controlled by the thickness of bedding planes as well as by high-angle to bedding fracture network. We investigate these processes along two coastal areas of Favignana Island by integrating geological data for 81 boulders, 49 rupture surfaces (called sockets) and fracture orientation and spacing with four radiocarbon dates, numerical hydrodynamic analysis, and hindcast numerical simulation data. Boulders are scattered along the carbonate platform as isolated blocks or in small groups, which form, as a whole, a discontinuous berm. Underwater surveys also highlight free boulders with sharp edges and sockets carved out in the rock platform. Boulders are composed of ruditic- to arenitic-size clastic carbonates. Their size ranges from 0.6 to 3.7 m, 0.55 to 2.4 m, and 0.2 to 1 m on the major (A), medium (B), and minor (C) axes, respectively. The highest value of mass estimation is 12.5 t. Almost all of boulders and sockets are characterized by a tabular or bladed shape. The comparisons between a) the fractures spacing and the length of A- and B-axes, and b) the frequency peaks of C-axis with the recurrent thickness of beds measured along the coastal zone demonstrate the litho-structural control in the size and shape of joint-bounded boulders. These comparisons, together with the similarity between the shapes of the boulders and those of the sockets as well as between the lithology of boulders and the areas surrounding the sockets, suggest that blocks originate by detachment from the platform edge. Thus, the most common pre-transport setting is the joint-bounded scenario. Hydrodynamic equations estimate that the storm wave heights necessary to initiate the transport of blocks diverge from 2 m to 8 m for joint-bounded boulders and from few tens of centimeters up to 11 m for submerged boulders. The comparison between the wave heights at the breaking point of the coastal zones with the results of hydrodynamic equations shows that waves approaching the coastline are able to transport all surveyed boulders. Our data suggest that boulders have been transported by several storm events, even in very recent times.
Thermal and molecular investigation of laser tissue welding
DOE Office of Scientific and Technical Information (OSTI.GOV)
Small, W., IV
1998-06-01
Despite the growing number of successful animal and human trials, the exact mechanisms of laser tissue welding remain unknown. Furthermore, the effects of laser heating on tissue on the molecular scale are not fully understood. To address these issues, a multi-front attack oil both extrinsic (solder/patch mediated) and intrinsic (laser only) tissue welding was launched using two-color infrared thermometry, computer modeling, weld strength assessment, biochemical assays, and vibrational spectroscopy. The coupling of experimentally measured surface temperatures with the predictive numerical simulations provided insight into the sub-surface dynamics of the laser tissue welding process. Quantification of the acute strength of themore » welds following the welding procedure enabled comparison among trials during an experiment, with previous experiments, and with other studies in the literature. The acute weld integrity also provided an indication of tile probability of long-term success. Molecular effects induced In the tissue by laser irradiation were investigated by measuring tile concentrations of specific collagen covalent crosslinks and characterizing the Fourier-Transform infrared (FTIR) spectra before and after the laser exposure.« less
NASA Astrophysics Data System (ADS)
Kashaev, Nikolai; Ventzke, Volker; Fomichev, Vadim; Fomin, Fedor; Riekehr, Stefan
2016-11-01
A Nd:YAG single-sided laser beam welding process study for Ti-6Al-4V butt joints and T-joints was performed to investigate joining techniques with regard to the process-weld morphology relationship. An alloy compatible filler wire was used to avoid underfills and undercuts. The quality of the butt joints and T-joints was characterized in terms of weld morphology, microstructure and mechanical properties. Joints with regular shapes, without visible cracks, pores, and geometrical defects were achieved. Tensile tests revealed high joint integrity in terms of strength and ductility for both the butt joint and T-joint geometries. Both the butt joints and T-joints showed base material levels of strength. The mechanical performance of T-joints was also investigated using pull-out tests. The performance of the T-joints in such tests was sensitive to the shape and morphology of the welds. Fracture always occurred in the weld without any plastic deformation in the base material outside the weld.
FORMATION MECHANISM FOR THE NANOSCALE AMORPHOUS INTERFACE IN PULSE-WELDED AL/FE BIMETALLIC SYSTEM
Li, Jingjing; Yu, Qian; Zhang, Zijiao; ...
2016-05-20
Pulse or impact welding traditionally has been referred to as “solid-state” welding. By integrating advanced interface characterizations and diffusion calculations, we report that the nanoscale amorphous interface in the pulse-welded Al/Fe bimetallic system is formed by rapid heating and melting of a thin Al layer at the interface, diffusion of iron atoms in the liquid aluminum, and subsequent rapid quenching with diffused iron atoms in solution. This finding challenges the commonly held belief regarding the solid-state nature of the impact-based welding process for dissimilar metals. Elongated ultra-fine grains with high dislocation density and ultra-fine equiaxed grains also are observed inmore » the weld interface vicinity on the steel and aluminum sides, respectively, which further confirms that melting and the resulted recrystallization occurred on the aluminum side of the interface.« less
FORMATION MECHANISM FOR THE NANOSCALE AMORPHOUS INTERFACE IN PULSE-WELDED AL/FE BIMETALLIC SYSTEM
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Jingjing; Yu, Qian; Zhang, Zijiao
Pulse or impact welding traditionally has been referred to as “solid-state” welding. By integrating advanced interface characterizations and diffusion calculations, we report that the nanoscale amorphous interface in the pulse-welded Al/Fe bimetallic system is formed by rapid heating and melting of a thin Al layer at the interface, diffusion of iron atoms in the liquid aluminum, and subsequent rapid quenching with diffused iron atoms in solution. This finding challenges the commonly held belief regarding the solid-state nature of the impact-based welding process for dissimilar metals. Elongated ultra-fine grains with high dislocation density and ultra-fine equiaxed grains also are observed inmore » the weld interface vicinity on the steel and aluminum sides, respectively, which further confirms that melting and the resulted recrystallization occurred on the aluminum side of the interface.« less
Formation mechanism for the nanoscale amorphous interface in pulse-welded Al/Fe bimetallic systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Jingjing; Yu, Qian; Zhang, Zijiao
Pulse or impact welding traditionally has been referred to as “solid-state” welding. By integrating advanced interface characterizations and diffusion calculations, we report that the nanoscale amorphous interface in the pulse-welded Al/Fe bimetallic system is formed by rapid heating and melting of a thin Al layer at the interface, diffusion of iron atoms in the liquid aluminum, and subsequent rapid quenching with diffused iron atoms in solution. This finding challenges the commonly held belief regarding the solid-state nature of the impact-based welding process for dissimilar metals. Elongated ultra-fine grains with high dislocation density and ultra-fine equiaxed grains also are observed inmore » the weld interface vicinity on the steel and aluminum sides, respectively, which further confirms that melting and the subsequent recrystallization occurred on the aluminum side of the interface.« less
Bottom-up nanoconstruction by the welding of individual metallic nanoobjects using nanoscale solder.
Peng, Yong; Cullis, Tony; Inkson, Beverley
2009-01-01
We report that individual metallic nanowires and nanoobjects can be assembled and welded together into complex nanostructures and conductive circuits by a new nanoscale electrical welding technique using nanovolumes of metal solder. At the weld sites, nanoscale volumes of a chosen metal are deposited using a sacrificial nanowire, which ensures that the nanoobjects to be bonded retain their structural integrity. We demonstrate by welding both similar and dissimilar materials that the use of nanoscale solder is clean, controllable, and reliable and ensures both mechanically strong and electrically conductive contacts. Nanoscale weld resistances of just 20Omega are achieved by using Sn solder. Precise engineering of nanowelds by this technique, including the chemical flexibility of the nanowire solder, and high spatial resolution of the nanowelding method, should result in research applications including fabrication of nanosensors and nanoelectronics constructed from a small number of nanoobjects, and repair of interconnects and failed nanoscale electronics.
Container weld identification using portable laser scanners
NASA Astrophysics Data System (ADS)
Taddei, Pierluigi; Boström, Gunnar; Puig, David; Kravtchenko, Victor; Sequeira, Vítor
2015-03-01
Identification and integrity verification of sealed containers for security applications can be obtained by employing noninvasive portable optical systems. We present a portable laser range imaging system capable of identifying welds, a byproduct of a container's physical sealing, with micrometer accuracy. It is based on the assumption that each weld has a unique three-dimensional (3-D) structure which cannot be copied or forged. We process the 3-D surface to generate a normalized depth map which is invariant to mechanical alignment errors and that is used to build compact signatures representing the weld. A weld is identified by performing cross correlations of its signature against a set of known signatures. The system has been tested on realistic datasets, containing hundreds of welds, yielding no false positives or false negatives and thus showing the robustness of the system and the validity of the chosen signature.
Dai, Gaole; Wang, Binjun; Xu, Shang; Lu, Yang; Shen, Yajing
2016-06-01
Cold welding has been regarded as a promising bottom-up nanofabrication technique because of its ability to join metallic nanostructures at room temperature with low applied stress and without introducing damage. Usually, the cold welding process can be done instantaneously for ultrathin nanowires (diameter <10 nm) in "head-to-head" joining. Here, we demonstrate that "dumbbell" shaped ultrathin gold nanorods can be cold welded in the "side-to-side" mode in a highly controllable manner and can form an extremely small nanogap via a relatively slow welding process (up to tens of minutes, allowing various functional applications). By combining in situ high-resolution transmission electron microscopic analysis and molecular dynamic simulations, we further reveal the underlying mechanism for this "side-to-side" welding process as being dominated by atom kinetics instead of thermodynamics, which provides critical insights into three-dimensional nanosystem integration as well as the building of functional nanodevices.
Milestones in welding technology
NASA Astrophysics Data System (ADS)
Dolby, Richard E.
2013-09-01
Sir Alan's PhD thesis describes his research into cracking during arc welding of armour steels. Throughout his career, he had a strong interest in defects of all types, how they formed in metallic structures and how the larger ones could be detected and sized by non-destructive techniques. He was also vitally concerned with how defects impacted on the engineering integrity of welded structures, particularly the risk of fracture in nuclear plant. This study presents a view of some of the major milestones in global welding technology that took place over the 60 or more years of Sir Alan's career and highlights those where he had a personal and direct involvement.
Prospects of very high power CO{sub 2} laser in welding
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goussain, J.C.; Vire, S.
1996-12-31
A 45 kW laser system was recently installed at Institut de Soudure (IS) in France in order to evaluate the possibilities of such high power beams in welding. Some results of welding various materials (Ta6V, C-steel, Cr-Ni alloys), different thicknesses (>30 mm) and large components (several meters) are presented. Some recent installations of high power laser equipment already integrated into production site or under development in shipbuilding and steel fabrication are described. Finally the objectives of an important R and D program launched recently for exploring the different aspects of laser welding in thick section steel fabrication is outlined.
Modeling of plasma and thermo-fluid transport in hybrid welding
NASA Astrophysics Data System (ADS)
Ribic, Brandon D.
Hybrid welding combines a laser beam and electrical arc in order to join metals within a single pass at welding speeds on the order of 1 m min -1. Neither autonomous laser nor arc welding can achieve the weld geometry obtained from hybrid welding for the same process parameters. Depending upon the process parameters, hybrid weld depth and width can each be on the order of 5 mm. The ability to produce a wide weld bead increases gap tolerance for square joints which can reduce machining costs and joint fitting difficulty. The weld geometry and fast welding speed of hybrid welding make it a good choice for application in ship, pipeline, and aerospace welding. Heat transfer and fluid flow influence weld metal mixing, cooling rates, and weld bead geometry. Cooling rate affects weld microstructure and subsequent weld mechanical properties. Fluid flow and heat transfer in the liquid weld pool are affected by laser and arc energy absorption. The laser and arc generate plasmas which can influence arc and laser energy absorption. Metal vapors introduced from the keyhole, a vapor filled cavity formed near the laser focal point, influence arc plasma light emission and energy absorption. However, hybrid welding plasma properties near the opening of the keyhole are not known nor is the influence of arc power and heat source separation understood. A sound understanding of these processes is important to consistently achieving sound weldments. By varying process parameters during welding, it is possible to better understand their influence on temperature profiles, weld metal mixing, cooling rates, and plasma properties. The current literature has shown that important process parameters for hybrid welding include: arc power, laser power, and heat source separation distance. However, their influence on weld temperatures, fluid flow, cooling rates, and plasma properties are not well understood. Modeling has shown to be a successful means of better understanding the influence of processes parameters on heat transfer, fluid flow, and plasma characteristics for arc and laser welding. However, numerical modeling of laser/GTA hybrid welding is just beginning. Arc and laser welding plasmas have been previously analyzed successfully using optical emission spectroscopy in order to better understand arc and laser plasma properties as a function of plasma radius. Variation of hybrid welding plasma properties with radial distance is not known. Since plasma properties can affect arc and laser energy absorption and weld integrity, a better understanding of the change in hybrid welding plasma properties as a function of plasma radius is important and necessary. Material composition influences welding plasma properties, arc and laser energy absorption, heat transfer, and fluid flow. The presence of surface active elements such as oxygen and sulfur can affect weld pool fluid flow and bead geometry depending upon the significance of heat transfer by convection. Easily vaporized and ionized alloying elements can influence arc plasma characteristics and arc energy absorption. The effects of surface active elements on heat transfer and fluid flow are well understood in the case of arc and conduction mode laser welding. However, the influence of surface active elements on heat transfer and fluid flow during keyhole mode laser welding and laser/arc hybrid welding are not well known. Modeling has been used to successfully analyze the influence of surface active elements during arc and conduction mode laser welding in the past and offers promise in the case of laser/arc hybrid welding. A critical review of the literature revealed several important areas for further research and unanswered questions. (1) The understanding of heat transfer and fluid flow during hybrid welding is still beginning and further research is necessary. (2) Why hybrid welding weld bead width is greater than that of laser or arc welding is not well understood. (3) The influence of arc power and heat source separation distance on cooling rates during hybrid welding are not known. (4) Convection during hybrid welding is not well understood despite its importance to weld integrity. (5) The influence of surface active elements on weld geometry, weld pool temperatures, and fluid flow during high power density laser and laser/arc hybrid welding are not known. (6) Although the arc power and heat source separation distance have been experimentally shown to influence arc stability and plasma light emission during hybrid welding, the influence of these parameters on plasma properties is unknown. (7) The electrical conductivity of hybrid welding plasmas is not known, despite its importance to arc stability and weld integrity. In this study, heat transfer and fluid flow are analyzed for laser, gas tungsten arc (GTA), and laser/GTA hybrid welding using an experimentally validated three dimensional phenomenological model. By evaluating arc and laser welding using similar process parameters, a better understanding of the hybrid welding process is expected. The role of arc power and heat source separation distance on weld depth, weld pool centerline cooling rates, and fluid flow profiles during CO2 laser/GTA hybrid welding of 321 stainless steel are analyzed. Laser power is varied for a constant heat source separation distance to evaluate its influence on weld temperatures, weld geometry, and fluid flow during Nd:YAG laser/GTA hybrid welding of A131 structural steel. The influence of oxygen and sulfur on keyhole and weld bead geometry, weld temperatures, and fluid flow are analyzed for high power density Yb doped fiber laser welding of (0.16 %C, 1.46 %Mn) mild steel. Optical emission spectroscopy was performed on GTA, Nd:YAG laser, and Nd:YAG laser/GTA hybrid welding plasmas for welding of 304L stainless steel. Emission spectroscopy provides a means of determining plasma temperatures and species densities using deconvoluted measured spectral intensities, which can then be used to calculate plasma electrical conductivity. In this study, hybrid welding plasma temperatures, species densities, and electrical conductivities were determined using various heat source separation distances and arc currents using an analytical method coupled calculated plasma compositions. As a result of these studies heat transfer by convection was determined to be dominant during hybrid welding of steels. The primary driving forces affecting hybrid welding fluid flow are the surface tension gradient and electromagnetic force. Fiber laser weld depth showed a negligible change when increasing the (0.16 %C, 1.46 %Mn) mild steel sulfur concentration from 0.006 wt% to 0.15 wt%. Increasing the dissolved oxygen content in weld pool from 0.0038 wt% to 0.0257 wt% increased the experimental weld depth from 9.3 mm to 10.8 mm. Calculated partial pressure of carbon monoxide increased from 0.1 atm to 0.75 atm with the 0.0219 wt% increase in dissolved oxygen in the weld metal and may explain the increase in weld depth. Nd:YAG laser/GTA hybrid welding plasma temperatures were calculated to be approximately between 7927 K and 9357 K. Increasing the Nd:YAG laser/GTA hybrid welding heat source separation distance from 4 mm to 6 mm reduced plasma temperatures between 500 K and 900 K. Hybrid welding plasma total electron densities and electrical conductivities were on the order of 1 x 1022 m-3 and 3000 S m-1, respectively.
Finite element based simulation on friction stud welding of metal matrix composites to steel
NASA Astrophysics Data System (ADS)
Hynes, N. Rajesh Jesudoss; Tharmaraj, R.; Velu, P. Shenbaga; Kumar, R.
2016-05-01
Friction welding is a solid state joining technique used for joining similar and dissimilar materials with high integrity. This new technique is being successfully applied to the aerospace, automobile, and ship building industries, and is attracting more and more research interest. The quality of Friction Stud Welded joints depends on the frictional heat generated at the interface. Hence, thermal analysis on friction stud welding of stainless steel (AISI 304) and aluminium silicon carbide (AlSiC) combination is carried out in the present work. In this study, numerical simulation is carried out using ANSYS software and the temperature profiles are predicted at various increments of time. The developed numerical model is found to be adequate to predict temperature distribution of friction stud weld aluminium silicon carbide/stainless steel joints.
2017-10-01
AWARD NUMBER: W81XWH-16-1-0785 TITLE: Prosthetic Smart Socket Technology to Improve Patient Interaction, Usability, Comfort, Fit and Function...2016 - 29 Sep 2017 4. TITLE AND SUBTITLE Prosthetic Smart Socket Technology to Improve Patient Interaction, Usability, Comfort, Fit and Function 5a...discomfort. 2. KEYWORDS: Provide a brief list of keywords (limit to 20 words). Prosthesis, prosthesis fit, technology , skin problems, amputee
Mello, C C; Lemos, C A A; Verri, F R; Dos Santos, D M; Goiato, M C; Pellizzer, E P
2017-09-01
The aim of this systematic review and meta-analysis was to compare the survival rate of the implants and the peri-implant tissue changes associated with implants inserted in fresh extraction sockets and those inserted in healed sockets. This review has been registered at PROSPERO under the number CRD42016043309. A systematic search was conducted by two reviewers independently in the databases PubMed/MEDLINE, Embase, and the Cochrane Library using different search terms; articles published until November 2016 were searched for. The searches identified 30 eligible studies. A total of 3,049 implants were installed in a total of 1,435 patients with a mean age of 46.68 years and a minimum of 6 months of follow-up. The survival rate of delayed implants (98.38%) was significantly greater than immediate implants (95.21%) (p=.001). For the marginal bone loss (p=.32), implant stability quotients values (p=.44), and pocket probing depth (p=.94) there was no significant difference between the analysed groups. The immediate implants placed in fresh sockets should be performed with caution because of the significantly lower survival rates than delayed implants inserted in healed sockets. Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
[The effect of osteogenic inducer on healing of tooth extraction sockets].
Chen, Junliang; Shan, Chuncheng; He, Yun; Xia, Delin
2012-06-01
To study the effect of osteogenic inducer (dexamethasone, beta-sodium glycerophosphate and Vitamin C) carried by gelatin sponge on healing and remodeling of tooth extraction sockets. Fifty rabbits were selected. After extracting the first premolars of bilateral maxillary, the right side tooth extraction sockets were filled with gelatin sponge containing osteogenic inducer as experimental side, tooth extraction sockets on left side were filled with gelatin sponge as control. Every ten rabbits were executed at the end of 1, 2, 4, 8, 12 weeks after tooth extraction. Bone density was measured through digital X-ray images. The specimens were examined by histology. The absorption height of alveolar bone at 12 weeks was measured. X-ray measurement showed that the bone density of experimental side was higher than that of control side at 2, 4, 8, 12 weeks, the difference had statistical significance (P<0.01). The histology examination showed that new bone formation in tooth extraction sockets of experimental side was earlier than that in control side. The absorptional height of alveolar bone had significant difference between experimental side and control side (P<0.01), of which experimental side was less. Filling the osteogenic inducer in tooth extraction sockets can promote the healing and new bone formation and prevent from alveolar bone absorption.
Detection of Prosthetic Knee Movement Phases via In-Socket Sensors: A Feasibility Study
El-Sayed, Amr M.; Tan, Kenneth Y. S.; Abu Osman, Noor Azuan
2015-01-01
This paper presents an approach of identifying prosthetic knee movements through pattern recognition of mechanical responses at the internal socket's wall. A quadrilateral double socket was custom made and instrumented with two force sensing resistors (FSR) attached to specific anterior and posterior sites of the socket's wall. A second setup was established by attaching three piezoelectric sensors at the anterior distal, anterior proximal, and posterior sites. Gait cycle and locomotion movements such as stair ascent and sit to stand were adopted to characterize the validity of the technique. FSR and piezoelectric outputs were measured with reference to the knee angle during each phase. Piezoelectric sensors could identify the movement of midswing and terminal swing, pre-full standing, pull-up at gait, sit to stand, and stair ascent. In contrast, FSR could estimate the gait cycle stance and swing phases and identify the pre-full standing at sit to stand. FSR showed less variation during sit to stand and stair ascent to sensitively represent the different movement states. The study highlighted the capacity of using in-socket sensors for knee movement identification. In addition, it validated the efficacy of the system and warrants further investigation with more amputee subjects and different sockets types. PMID:25945365
Chen, J; He, Y; Shan, C; Pan, Q; Li, M; Xia, D
2015-10-01
An osteogenic inducer (OI) consisting of dexamethasone, vitamin C, and β-sodium glycerophosphate has the capacity to induce bone formation in vitro. The aim of this study was to assess the efficacy of the application of this OI on extraction socket healing. The bilateral first mandibular premolars were extracted from 75 New Zealand rabbits. Gelatin sponges carrying OI were implanted into the sockets. Sockets undergoing implantation of gelatin sponges alone were also evaluated, as well as non-implantation sockets. Specimens from each group were evaluated radiographically, histologically, and histomorphometrically using haematoxylin-eosin staining. Results showed earlier new bone formation and higher bone quality and quantity in the OI group compared to the other groups, and the differences were significant at 2, 4, 8, and 12 weeks postoperative. The OI significantly reduced the absorption of alveolar bone in terms of height; however, changes in the width were not significantly different between the three groups (P>0.05). The OI was shown to have a positive effect on healing of the tooth extraction sockets, was inexpensive, and was convenient to use during the operational procedure; therefore this could represent a promising implant material for human clinical application. Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
A fundamental study on the structural integrity of magnesium alloys joined by friction stir welding
NASA Astrophysics Data System (ADS)
Rao, Harish Mangebettu
The goal of this research is to study the factors that influence the physical and mechanical properties of lap-shear joints produced using friction stir welding. This study focuses on understanding the effect of tool geometry and weld process parameters including the tool rotation rate, tool plunge depth and dwell time on the mechanical performance of similar magnesium alloy and dissimilar magnesium to aluminum alloy weld joints. A variety of experimental activities were conducted including tensile and fatigue testing, fracture surface and failure analysis, microstructure characterization, hardness measurements and chemical composition analysis. An investigation on the effect of weld process conditions in friction stir spot welding of magnesium to magnesium produced in a manner that had a large effective sheet thickness and smaller interfacial hook height exhibited superior weld strength. Furthermore, in fatigue testing of friction stir spot welded of magnesium to magnesium alloy, lap-shear welds produced using a triangular tool pin profile exhibited better fatigue life properties compared to lap-shear welds produced using a cylindrical tool pin profile. In friction stir spot welding of dissimilar magnesium to aluminum, formation of intermetallic compounds in the stir zone of the weld had a dominant effect on the weld strength. Lap-shear dissimilar welds with good material mixture and discontinues intermetallic compounds in the stir zone exhibited superior weld strength compared to lap-shear dissimilar welds with continuous formation of intermetallic compounds in the stir zone. The weld structural geometry like the interfacial hook, hook orientation and bond width also played a major role in influencing the weld strength of the dissimilar lap-shear friction stir spot welds. A wide scatter in fatigue test results was observed in friction stir linear welds of aluminum to magnesium alloys. Different modes of failure were observed under fatigue loading including crack propagation into the top sheet, into the bottom sheet, and interfacial separation. Investigation of the tested welds revealed that the voids in the weld nugget reduced the weld strength, resulting in lower fatigue life. A thin layer of IMCs formed along the faying surface which accelerated the fatigue failure.
Arun, S; Kanagaraj, S
2016-06-01
A socket plays a vital role in giving the comfort to the amputees. However, the accumulation of heat inside the socket and its weight led to increase their metabolic cost. Hence, an attempt was made to increase the performance of the epoxy based sandwich composites to be used for the socket by reinforcing multiwalled carbon nanotubes (MWCNT), which was varied from 0.1 to 0.5wt%. It was homogeneously dispersed in epoxy to obtain the desired properties, where the enhancement of thermal conductivity, compressive strength and modulus of epoxy was observed to be 76.7%, 62.6% and 20.2%, respectively at 0.3wt% of MWCNT concentration beyond which the mechanical properties were found to be decreased. Hence, the epoxy, E-glass plain fabric, 2-10 layers of stockinet and 0.3wt% of MWCNT were used to prepare the sandwich composites. The flexural strength and thermal conductivity of 0.3wt% of MWCNT reinforced sandwich composites were found to be improved by 11.38±1.5% and 29.8±1.3% for the 4-10 layers and up to 10 layers of stockinet, respectively compared to unreinforced sandwich composites, which helped to reduce the weight of the socket and decrease the heat accumulation inside the socket. Thus, it is suggested to be explored for the application of socket in trans-femoral amputees to increase their comfort level by decreasing the metabolic cost. Copyright © 2015 Elsevier Ltd. All rights reserved.
Sequential healing of open extraction sockets. An experimental study in monkeys.
Scala, Alessandro; Lang, Niklaus P; Schweikert, Michael T; de Oliveira, José Américo; Rangel-Garcia, Idelmo; Botticelli, Daniele
2014-03-01
To describe the sequential healing of open extraction sockets at which no attempts to obtain a primary closure of the coronal access to the alveolus have been made. The third mandibular premolar was extracted bilaterally in 12 monkeys, and no sutures were applied to close the wound. The healing after 4, 10, 20, 30, 90 and 180 days was morphometrically studied. After 4 days of healing, a blood clot mainly occupied the extraction sockets, with the presence of an inflammatory cells' infiltrate. A void was confined in the central zones of the coronal and middle regions, in continuity with the entrance of the alveoli. At 10 days, the alveolus was occupied by a provisional matrix, with new bone formation lining the socket bony walls. At 20 days, the amount of woven bone was sensibly increasing. At 30 days, the alveolar socket was mainly occupied by mineralized immature bone at different stages of healing. At 90 and 180 days, the amount of mineralized bone decreased and substituted by trabecular bone and bone marrow. Bundle bone decreased from 95.5% at 4 days to 7.6% at 180 days, of the whole length of the inner alveolar surface. Modeling processes start from the lateral and apical walls of the alveolus, leading to the closure of the socket with newly formed bone within a month from extraction. Remodeling processes will follow the previous stages, resulting in trabecular and bone marrow formation and in a corticalization of the socket access. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.
Gürbüzer, Bahadir; Pikdöken, Levent; Tunali, Mustafa; Urhan, Muammer; Küçükodaci, Zafer; Ercan, Feriha
2010-05-01
To evaluate the effect of platelet-rich fibrin (PRF) on the early bone healing process with bone scintigraphy based on technetium-99m methylene diphosphonate uptake in third molar extraction sockets. Fourteen patients with bilaterally soft tissue impacted third mandibular molars were included in the study. The right and left impacted third molars were surgically extracted in the same session. PRF was randomly administered into one of the extraction sockets, whereas the contralateral sockets were left without treatment. Four weeks after surgery, scintigrams were obtained to evaluate scintigraphic differences between PRF-treated and non-PRF-treated sockets. After completion of the clinical study, PRF samples were evaluated by light and scanning electron microscopy. The average increase in technetium-99m methylene diphosphonate uptake as an indication of enhanced bone healing did not differ significantly between PRF-treated and non-PRF-treated sockets 4 weeks postoperatively (P > .05). Abundant fibrin and inflammatory cells were observed by light microscopic examination of PRF samples. Scanning electron microscopic analysis of PRF revealed the existence of platelet aggregates in a fibrin network and crystalline particles on the outer surface of PRF. PRF might not lead to enhanced bone healing in soft tissue impacted mandibular third molar extraction sockets 4 weeks after surgery. PRF exhibits the potential characteristics of an autologous fibrin matrix. However, whether the presence of crystal-like particles on the outer surface of PRF alters bone healing should be investigated further. Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
Effect of plasma rich in growth factors on alveolar osteitis
Haraji, Afshin; Lassemi, Eshagh; Motamedi, Mohammad Hosein Kalantar; Alavi, Maryam; Adibnejad, Saman
2012-01-01
Introduction: The high prevalence of dry socket or alveolar osteitis (AO) is of concern in surgical removal of third molars. The aim of the present study was to assess the preventive effect of plasma rich in growth factors (PRGF) on AO and also its effect on pain management and healing acceleration in third molar extraction sockets of high-risk patients. Materials and Methods: This split-mouth, double-blind clinical trial included 40 bilateral third molar extractions (80 sockets) with at least one identified risk factor for AO. PRGF was obtained from patient's own blood, based on manufacturer's instruction, and blindly placed in one of the two bilateral sockets (PRGF group; n = 20) of each patient. The contralateral socket was treated with a placebo (control group; n = 20). Samples were evaluated for AO and pain incidence on days 2, 3 and 4 and healing and infection on days 3 and 7. Data were analyzed in SPSS v16 using Wilcoxon test. Results: There was a significant difference in dry socket and pain incidence and healing rate between the two groups. Intensity of pain and occurrence of dry socket in the study group was lower than the controls. Also the healing rate was higher (P < 0.05) for the PRGF group. No sign of infection was seen in either group. Conclusion: The application of PRGF may significantly reduce the incidence of AO or its associated pain and may accelerate healing. The prophylactic use of PRGF following third molar extraction may be suggested especially in the patients at risk of AO. PMID:23251056
Beam Splitter For Welding-Torch Vision System
NASA Technical Reports Server (NTRS)
Gilbert, Jeffrey L.
1991-01-01
Compact welding torch equipped with along-the-torch vision system includes cubic beam splitter to direct preview light on weldment and to reflect light coming from welding scene for imaging. Beam splitter integral with torch; requires no external mounting brackets. Rugged and withstands vibrations and wide range of temperatures. Commercially available, reasonably priced, comes in variety of sizes and optical qualities with antireflection and interference-filter coatings on desired faces. Can provide 50 percent transmission and 50 percent reflection of incident light to exhibit minimal ghosting of image.
Bagless transfer process and apparatus for radioactive waste confinement
Maxwell, D.N.; Hones, R.H.; Rogers, M.L.
1998-04-14
A process and apparatus are provided for removing radioactive material from a glovebox, placing the material in a stainless steel storage vessel in communication with the glovebox, and sealing the vessel with a welded plug. The vessel is then severed along the weld, a lower half of the plug forming a closure for the vessel. The remaining welded plug half provides a seal for the remnant portion of the vessel and thereby maintains the sealed integrity of the glovebox. 7 figs.
Bagless transfer process and apparatus for radioactive waste confinement
Maxwell, David N.; Hones, Robert H.; Rogers, M. Lane
1998-01-01
A process and apparatus is provided for removing radioactive material from a glovebox, placing the material in a stainless steel storage vessel in communication with the glovebox, and sealing the vessel with a welded plug. The vessel is then severed along the weld, a lower half of the plug forming a closure for the vessel. The remaining welded plug half provides a seal for the remnant portion of the vessel and thereby maintains the sealed integrity of the glovebox.
Discharge and infection in retinoblastoma post-enucleation sockets
Mourits, Daphne L; Hartong, Dyonne T; Budding, Andries E; Bosscha, Machteld I; Tan, H Stevie; Moll, Annette C
2017-01-01
Purpose To investigate the causes and treatment options for socket discharge and infection in patients enucleated for retinoblastoma (Rb). Methods A questionnaire was filled out by (parents of) ocular prosthesis-wearing patients with a history of enucleation as treatment for Rb. We collected data on patients’ characteristics, cleaning habits of the prosthesis, frequency of socket irritation, discharge, and infection, and use of antibiotics. With ordinal logistic regression analysis, factors related to the outcome parameters (frequency of irritation, mucoid and purulent discharge) were identified. In a subset of young asymptomatic and symptomatic patients, a swab culture of the socket was performed to determine the presence of microorganisms. Results A total of 186 patients or their parents (mean age of the patients: 17.3 years, ranging from 0.8 to 88.3 years) filled out the questionnaire. Irritation, mucoid discharge, and purulent discharge were frequently (once a month or more often) experienced in 75 (39.5%), 127 (66.8%), and 15 (13.2%) sockets, respectively. Younger age was associated with a higher frequency of mucoid and purulent discharge. Radiation therapy, chemotherapy, gender, age at surgery, cleaning frequency, and nocturnal wear were not associated with the outcome parameters. In a subgroup of 26 patients, the sockets were swabbed and cultured. All symptomatic patients had a positive bacterial culture versus 15% (2/13) of the asymptomatic patients (P<0.001). Common cold was correlated with both symptoms and presence of bacteria. Haemophilus influenzae and Staphylococcus aureus were the species most frequently cultured. Conclusion Ocular prosthesis-wearing patients often experienced mucoid discharge, and less often irritation and socket infection. These complaints were found to decrease with increasing age, but did not seem to be influenced by cleaning or wearing habits. Symptomatic sockets, with and without discharge, were correlated with the presence of pathogenic bacteria for which local antibiotic treatment seemed effective in most cases. PMID:28280296
Cooper, Lyndon F; Reside, Glenn J; Raes, Filiep; Garriga, Joan Soliva; Tarrida, Luis Giner; Wiltfang, Jörg; Kern, Matthias; De Bruyn, Hugo
2014-01-01
This 5-year prospective multicenter study compared implant survival and success, peri-implant health and soft tissue responses, crestal bone level stability, and complication rates following immediate loading of single OsseoSpeed implants placed in anterior maxillary healed ridges or extraction sockets. Individuals requiring anterior tooth replacement with single implants were treated and immediately provisionalized. Definitive all-ceramic crowns were placed at 12 weeks. Implant survival, bone levels, soft tissue levels, and peri-implant health were monitored for 5 years. One hundred thirteen patients received implants in fresh sockets (55) and healed ridges (58). After 5 years, 45 and 49 patients remained for evaluation, respectively. During the first year, three implants failed in the extraction socket group (94.6% survival) and one implant failed in the healed ridge group (98.3% survival); this difference was not significant. No further implant failures were recorded. After 5 years, the interproximal crestal bone levels were located a mean of 0.43 ± 0.63 mm and 0.38 ± 0.62 mm from the reference points of implants in sockets and healed ridges (not a significant difference). In both groups, papillae increased over time and peri-implant mucosal zenith positions were stable from the time of definitive crown placement in sockets and healed ridges. Compared to flap surgery for implants in healed ridges, flapless surgery resulted in increased peri-implant mucosal tissue dimension (average, 0.78 ± 1.34 mm vs 0.19 ± 0.79 mm). After 5 years, the bone and soft tissue parameters that characterize implant success and contribute to dental implant esthetics were similar following the immediate provisionalization of implants in sockets and healed ridges. The overall tissue responses and reported implant survival support the immediate provisionalization of dental implants in situations involving healed ridges and, under ideal circumstances, extraction sockets.
Discharge and infection in retinoblastoma post-enucleation sockets.
Mourits, Daphne L; Hartong, Dyonne T; Budding, Andries E; Bosscha, Machteld I; Tan, H Stevie; Moll, Annette C
2017-01-01
To investigate the causes and treatment options for socket discharge and infection in patients enucleated for retinoblastoma (Rb). A questionnaire was filled out by (parents of) ocular prosthesis-wearing patients with a history of enucleation as treatment for Rb. We collected data on patients' characteristics, cleaning habits of the prosthesis, frequency of socket irritation, discharge, and infection, and use of antibiotics. With ordinal logistic regression analysis, factors related to the outcome parameters (frequency of irritation, mucoid and purulent discharge) were identified. In a subset of young asymptomatic and symptomatic patients, a swab culture of the socket was performed to determine the presence of microorganisms. A total of 186 patients or their parents (mean age of the patients: 17.3 years, ranging from 0.8 to 88.3 years) filled out the questionnaire. Irritation, mucoid discharge, and purulent discharge were frequently (once a month or more often) experienced in 75 (39.5%), 127 (66.8%), and 15 (13.2%) sockets, respectively. Younger age was associated with a higher frequency of mucoid and purulent discharge. Radiation therapy, chemotherapy, gender, age at surgery, cleaning frequency, and nocturnal wear were not associated with the outcome parameters. In a subgroup of 26 patients, the sockets were swabbed and cultured. All symptomatic patients had a positive bacterial culture versus 15% (2/13) of the asymptomatic patients ( P <0.001). Common cold was correlated with both symptoms and presence of bacteria. Haemophilus influenzae and Staphylococcus aureus were the species most frequently cultured. Ocular prosthesis-wearing patients often experienced mucoid discharge, and less often irritation and socket infection. These complaints were found to decrease with increasing age, but did not seem to be influenced by cleaning or wearing habits. Symptomatic sockets, with and without discharge, were correlated with the presence of pathogenic bacteria for which local antibiotic treatment seemed effective in most cases.
Three-Dimensional Wiring for Extensible Quantum Computing: The Quantum Socket
NASA Astrophysics Data System (ADS)
Béjanin, J. H.; McConkey, T. G.; Rinehart, J. R.; Earnest, C. T.; McRae, C. R. H.; Shiri, D.; Bateman, J. D.; Rohanizadegan, Y.; Penava, B.; Breul, P.; Royak, S.; Zapatka, M.; Fowler, A. G.; Mariantoni, M.
2016-10-01
Quantum computing architectures are on the verge of scalability, a key requirement for the implementation of a universal quantum computer. The next stage in this quest is the realization of quantum error-correction codes, which will mitigate the impact of faulty quantum information on a quantum computer. Architectures with ten or more quantum bits (qubits) have been realized using trapped ions and superconducting circuits. While these implementations are potentially scalable, true scalability will require systems engineering to combine quantum and classical hardware. One technology demanding imminent efforts is the realization of a suitable wiring method for the control and the measurement of a large number of qubits. In this work, we introduce an interconnect solution for solid-state qubits: the quantum socket. The quantum socket fully exploits the third dimension to connect classical electronics to qubits with higher density and better performance than two-dimensional methods based on wire bonding. The quantum socket is based on spring-mounted microwires—the three-dimensional wires—that push directly on a microfabricated chip, making electrical contact. A small wire cross section (approximately 1 mm), nearly nonmagnetic components, and functionality at low temperatures make the quantum socket ideal for operating solid-state qubits. The wires have a coaxial geometry and operate over a frequency range from dc to 8 GHz, with a contact resistance of approximately 150 m Ω , an impedance mismatch of approximately 10 Ω , and minimal cross talk. As a proof of principle, we fabricate and use a quantum socket to measure high-quality superconducting resonators at a temperature of approximately 10 mK. Quantum error-correction codes such as the surface code will largely benefit from the quantum socket, which will make it possible to address qubits located on a two-dimensional lattice. The present implementation of the socket could be readily extended to accommodate a quantum processor with a (10 ×10 )-qubit lattice, which would allow for the realization of a simple quantum memory.
Biomechanical Analysis of a Filiform Mechanosensory Hair Socket of Crickets.
Joshi, Kanishka; Mian, Ahsan; Miller, John
2016-08-01
Filiform mechanosensory hairs of crickets are of great interest to engineers because of the hairs' highly sensitive response to low-velocity air-currents. In this study, we analyze the biomechanical properties of filiform hairs of the cercal sensory system of a common house cricket. The cercal sensory system consists of two antennalike appendages called cerci that are situated at the rear of the cricket's abdomen. Each cercus is covered with 500-750 flow sensitive filiform mechanosensory hairs. Each hair is embedded in a complex viscoelastic socket that acts as a spring and dashpot system and guides the movement of the hair. When a hair deflects due to the drag force induced on its length by a moving air-current, the spiking activity of the neuron that innervates the hair changes and the combined spiking activity of all hairs is extracted by the cercal sensory system. Filiform hairs have been experimentally studied by researchers, though the basis for the hairs' biomechanical characteristics is not fully understood. The socket structure has not been analyzed experimentally or theoretically from a mechanical standpoint, and the characterization that exists is mathematical in nature and only provides a very rudimentary approximation of the socket's spring nature. This study aims to understand and physically characterize the socket's behavior and interaction with the filiform hair by examining hypotheses about the hair and socket biomechanics. A three-dimensional computer-aided design (CAD) model was first created using confocal microscopy images of the hair and socket structure of the cricket, and then finite-element analyses (FEAs) based on the physical conditions that the insect experiences were simulated. The results show that the socket can act like a spring; however, it has two-tier rotational spring constants during pre- and postcontacts of iris and hair bulge due to its constitutive nonstandard geometric shapes.
Evora® chromium-cobalt dual mobility socket: results at a minimum 10 years' follow-up.
Leclercq, S; Benoit, J Y; de Rosa, J P; Tallier, E; Leteurtre, C; Girardin, P H
2013-12-01
The Evora chromium-cobalt alloy dual mobility socket claims to display a large articulation tribology different from that of stainless steel models, limiting the risk of intraprosthetic dislocation and wear. The present study reports a minimum of 10years' follow-up in a multicenter prospective series of 200 sockets previously reported on at 5years. The use of chromium-cobalt in dual mobility sockets provides a low rate of failure at 10years, especially as regards to osteolysis and intraprosthetic dislocation. Two hundred hydroxyapatite-coated molded chromium-cobalt sockets without titanium interface were implanted without cement in 194 patients with a mean age of 70 years (range, 32-91 years). Clinical results were assessed on Postel Merle d'Aubigné and Harris scores, plain radiographs and survival analysis. At a mean 11 years' follow-up (10-13 years), 56 patients had died and 31 were lost to follow-up. Four underwent surgical revision (3 femoral components, and 1 socket for migration at 9 years with complete disappearance of the hydroxyapatite). A total of 109 implants were analyzable in 107 patients with a mean age of 81 years (55-93 years). At follow-up, the mean Harris score was 90 (75-96) and the PMA score 16.3 (14-18). There were no cases of loosening (except for the case reoperated on at 9 years) and no acetabular radiolucency or cysts. There were 2 cases of non-evolutive femoral radiolucency and 10 of femoral granuloma, involving head size > 22 mm (P<0.0001) and a cemented titanium stem (P=0.004) as risk factors. There were no dislocations in the large or small articulation. Ten-year survival was 99% (95% CI: 97.3%-100%) with socket revision as censorship criterion. The absence of dislocation in both small and large articulations confirmed the efficacy of the dual mobility concept and suggested an advantage for chromium-cobalt sockets in reducing the rate of intraprosthetic dislocation and preventing blockage of the large articulation by a better performance in the friction couple. Granulomas were associated with wear in cemented titanium stems and with heads greater than 22 mm in diameter. Ten-year survival was 99% (censorship criterion: revision for socket failure); there was, however, one case of socket loosening with disappearance of the hydroxyapatite, indicating that surveillance should be continued in this cohort. Copyright © 2013 Elsevier Masson SAS. All rights reserved.
Morales, Ricardo; Badesa, Francisco J; García-Aracil, Nicolas; Perez-Vidal, Carlos; Sabater, Jose María
2012-01-01
This paper presents a microdevice for monitoring, control and management of electric loads at home. The key idea is to compact the electronic design as much as possible in order to install it inside a Schuko socket. Moreover, the electronic Schuko socket (electronic microdevice + Schuko socket) has the feature of communicating with a central unit and with other microdevices over the existing powerlines. Using the existing power lines, the proposed device can be installed in new buildings or in old ones. The main use of this device is to monitor, control and manage electric loads to save energy and prevent accidents produced by different kind of devices (e.g., iron) used in domestic tasks. The developed smart device is based on a single phase multifunction energy meter manufactured by Analog Devices (ADE7753) to measure the consumption of electrical energy and then to transmit it using a serial interface. To provide current measurement information to the ADE7753, an ultra flat SMD open loop integrated circuit current transducer based on the Hall effect principle manufactured by Lem (FHS-40P/SP600) has been used. Moreover, each smart device has a PL-3120 smart transceiver manufactured by LonWorks to execute the user's program, to communicate with the ADE7753 via serial interface and to transmit information to the central unit via powerline communication. Experimental results show the exactitude of the measurements made using the developed smart device.
Prosthetics & Orthotics Manufacturing Initiative (POMI)
2012-12-21
could also allow for ‘virtual innovation,’ the testing of very novel socket designs without ever risking a patient’s well-being. In order to inform...that RL so that a computer aided design (CAD) socket can be fabricated for that individual. 3. Test the fit of the CAD socket through...developed a 4 layer braid laminate design that worked for manufacturing purposes but there was no testing of the laminate to determine if all strength
Measurement of Forces and Moments Transmitted to the Residual Limb
2008-08-01
leg and residual limb, the condition of your residual limb including touch and pressure sensation, and the type of components used in your prosthesis ...measured by a tri-axial transducer mounted on the pylon of a transtibial prosthesis distal to the socket can be used to estimate the intra-socket...alignment has been developed, and IRB approval has been obtained. 15. SUBJECT TERMS Amputees, prosthesis alignment, socket pressure, gait, force and moment
2012-01-01
Background A cursory review of the current socket preservation literatures well depicts the necessity of further esthetic considerations through the corrective procedures of the alveolar ridge upon and post extraction. A new technique has been described here is a rotational pedicle combined epithelialized and connective tissue graft (RPC graft) adjunct with immediate guided tissue regeneration (GBR) procedure. Results We reviewed this technique through a case report and discuss it’s benefit in compare to other socket preservation procedures. Conclusion The main advantages of RPC graft would be summarized as follows: stable primary closure during bone remodeling, saving or crating sufficient vestibular depth, making adequate keratinized gingiva on the buccal surface, and being esthetically pleasant. PMID:22540920
Vane segment support and alignment device
McLaurin, L.D.; Sizemore, J.D.
1999-07-13
A support and alignment assembly for supporting and aligning a vane segment is provided. The support and alignment assembly comprises a torque plate which defines an opening for receiving an eccentric pin and a locking end member for receiving a lock socket member. An eccentric pin adjustably supported by the torque plate opening for supporting and aligning a vane segment is provided. A lock socket member adapted to securely receive the eccentric pin and rotated therewith, and adjustably engage the torque plate locking end is provided. The lock socket member receives the eccentric pin, such that when the eccentric pin is adjusted to align the vane segment, the lock socket member engages the torque plate locking end to secure the vane segment in the desired position. 5 figs.
Vane segment support and alignment device
McLaurin, Leroy Dixon; Sizemore, John Derek
1999-01-01
A support and alignment assembly for supporting and aligning a vane segment is provided. The support and alignment assembly comprises a torque plate which defines an opening for receiving an eccentric pin and a locking end member for receiving a lock socket member. An eccentric pin adjustably supported by the torque plate opening for supporting and aligning a vane segment is provided. A lock socket member adapted to securely receive the eccentric pin and rotated therewith, and adjustably engage the torque plate locking end is provided. The lock socket member receives the eccentric pin, such that when the eccentric pin is adjusted to align the vane segment, the lock socket member engages the torque plate locking end to secure the vane segment in the desired position.
Tomographical process monitoring of laser transmission welding with OCT
NASA Astrophysics Data System (ADS)
Ackermann, Philippe; Schmitt, Robert
2017-06-01
Process control of laser processes still encounters many obstacles. Although these processes are stable, a narrow process parameter window during the process or process deviations have led to an increase on the requirements for the process itself and on monitoring devices. Laser transmission welding as a contactless and locally limited joining technique is well-established in a variety of demanding production areas. For example, sensitive parts demand a particle-free joining technique which does not affect the inner components. Inline integrated non-destructive optical measurement systems capable of providing non-invasive tomographical images of the transparent material, the weld seam and its surrounding areas with micron resolution would improve the overall process. Obtained measurement data enable qualitative feedback into the system to adapt parameters for a more robust process. Within this paper we present the inline monitoring device based on Fourier-domain optical coherence tomography developed within the European-funded research project "Manunet Weldable". This device, after adaptation to the laser transmission welding process is optically and mechanically integrated into the existing laser system. The main target lies within the inline process control destined to extract tomographical geometrical measurement data from the weld seam forming process. Usage of this technology makes offline destructive testing of produced parts obsolete. 1,2,3,4
NASA Astrophysics Data System (ADS)
Carrasco-González, L. A.; Hurtado-Delgado, E.; Reyes-Valdés, F. A.
The aim of this investigation is to evaluate the distortions generated in welding unions of stainless steel 304 by effect of the welding temperature and the microestructural changes. The joint design is a 100 × 100 mm steel plate of 3 mm thickness. The plate was joined to a tube of 50 mm diameter and 2 mm thickness, which has a defined angular cut; therefore, the trajectory followed by the seam has an elliptic form. Temperature data acquisition was developed by type K thermocouples, placed in pairs at 0°, 90°, 180° and 270° along the welding trajectory and connected to a data acquisition device yo obtain the measures to generate time-temperature plots. The welding process was executed by a KUKA ®; KR16 welding robot with an integrated GMAW (Gas metal arc welding) process where the input parameters of voltage, wire feed and travel speed are set to constant. The distortion of the work piece was measured using a laser scanning technique that generates a point cloud with the VXelements TM software for comparison between the pre and post-weld condition. Microstructural evaluation was performed on transversal sections of the seam, at the mentioned angles for correlation.
NASA Astrophysics Data System (ADS)
Correa, Nekane; Vadillo, Ernesto G.; Santamaria, Javier; Blanco-Lorenzo, Julio
2018-01-01
This study investigates the influence on the wheel-rail contact forces of the running speed and the shape and position of weld defects along the track. For this purpose, a vertical dynamic model in the space domain is used. The model is obtained from the transformation between the domains of frequency and space using a Rational Fraction Polynomials (RFP) method, which is modified with multiobjective genetic algorithms in order to improve the fitting of track receptance and to assist integration during simulations. This produces a precise model with short calculation times, which is essential to this study. The wheel-rail contact is modelled using a non-linear Hertz spring. The contact forces are studied for several types of characteristic welds. The way in which forces vary as a function of weld position and running speed is studied for each type of weld. This paper studies some of the factors that affect the maximum forces when the vehicle moves over a rail weld, such as weld geometry, parametric excitation and contact stiffness. It is found that the maximum force in the wheel-rail contact when the vehicle moves over a weld is not always proportional to the running speed. The paper explains why it is not proportional in specific welds.
The effect of weld stresses on weld quality. [stress fields and metal cracking
NASA Technical Reports Server (NTRS)
Chihoski, R. A.
1972-01-01
A narrow heat source raises the temperature of a spot on a solid piece of material like metal. The high temperature of the spot decreases with distance from the spot. This is true whether the heat source is an arc, a flame, an electron beam, a plasma jet, a laser beam, or any other source of intense, narrowly defined heat. Stress and strain fields around a moving heat source are organized into a coherent visible system. It is shown that five stresses act across the weld line in turn as an arc passes. Their proportions and positions are considerably altered by weld parameters or condition changes. These pushes and pulls affect the metallurgical character and integrity of the weld area even when there is no apparent difference between after-the-fact examples.
Wood, Sarah A; Strait, David S; Dumont, Elizabeth R; Ross, Callum F; Grosse, Ian R
2011-07-07
Several finite element models of a primate cranium were used to investigate the biomechanical effects of the tooth sockets and the material behavior of the periodontal ligament (PDL) on stress and strain patterns associated with feeding. For examining the effect of tooth sockets, the unloaded sockets were modeled as devoid of teeth and PDL, filled with teeth and PDLs, or simply filled with cortical bone. The third premolar on the left side of the cranium was loaded and the PDL was treated as an isotropic, linear elastic material using published values for Young's modulus and Poisson's ratio. The remaining models, along with one of the socket models, were used to determine the effect of the PDL's material behavior on stress and strain distributions under static premolar biting and dynamic tooth loading conditions. Two models (one static and the other dynamic) treated the PDL as cortical bone. The other two models treated it as a ligament with isotropic, linear elastic material properties. Two models treated the PDL as a ligament with hyperelastic properties, and the other two as a ligament with viscoelastic properties. Both behaviors were defined using published stress-strain data obtained from in vitro experiments on porcine ligament specimens. Von Mises stress and strain contour plots indicate that the effects of the sockets and PDL material behavior are local. Results from this study suggest that modeling the sockets and the PDL in finite element analyses of skulls is project dependent and can be ignored if values of stress and strain within the alveolar region are not required. Copyright © 2011 Elsevier Ltd. All rights reserved.
Kim, Jung-Ju; Schwarz, Frank; Song, Hyun Young; Choi, YoonMi; Kang, Kyung-Rim; Koo, Ki-Tae
2017-06-01
This study aimed to evaluate the dynamics of newly bone formation and dimensional change in diseased extraction sockets using Bio-Oss ® Collagen with or without a collagen membrane. In six beagle dogs, right and left 3rd and 4th mandibular premolars were hemisected and the distal roots were removed. Combined endodontic-periodontic lesions were induced in all sites using black silk, collagen sponge, endodontic files, and application of Porphyromonas gingivalis. After 4 months, among 4 premolars, three teeth were randomly selected per dog and allocated to the following experimental groups: Control group (no treatment but debridement), Test 1 group (only Bio-Oss ® Collagen graft), and Test 2 group (Bio-Oss ® Collagen graft with a collagen membrane). After 7 months from the baseline, the beagle dogs were sacrificed for histomorphometric and Micro-CT analysis. The vertical distance between buccal and lingual crests in the Control group (2.22 ± 0.26 mm) and Test 2 group (1.80 ± 0.16 mm) was significantly different. The socket of the Test 2 group (27.04 ± 5.25%) was occupied by a greater quantity of bone graft compared to the Test 1 group (18.49 ± 2.11%). Ridge preservation in diseased extraction sockets could compensate for buccal bone resorption by contact osteogenesis surrounding the bone graft particles at the bucco-coronal area during socket healing, and the application of a collagen membrane at the entrance of the socket is useful for preserving graft material at the coronal part of the socket. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Ennion, Liezel; Johannesson, Anton; Rhoda, Anthea
2017-10-01
Challenges exist with the provision of appropriate mobility assistive devices in rural areas. The use of the direct manufacturing prosthetic socket system is a possible solution to these challenges. The objective of this study was to test and explore the clients' perspectives with the application of this device. Within a mixed-methods approach, a longitudinal sequential explanatory design was applied. The Orthotic and Prosthetic User's Survey was administered to explore the use of the direct manufacturing prosthetic socket system in terms of function, health-related quality of life and client satisfaction. A conveniently selected sample of 21 individuals who suffered a unilateral trans-tibial amputation was included. Data were collected at 1, 3 and 6 months post fitting, and two focus group discussions were also administered. Of the 21 participants recruited, 11 returned for follow up. Although participants reported favourably about the prosthesis, their scores were generally worse than the norms with regard to function and quality of life. Participants highlighted the need for improvement in the cosmetic appearance of the prosthesis. The direct manufacturing prosthetic socket system could be considered as an alternative technique of socket manufacturing for individuals living in rural areas due to the shorter manufacture time and promising initial results, but further research on this topic with a bigger sample is recommended. Clinical relevance The direct manufacturing prosthetic socket system may be considered as an alternative to the traditional prosthetic socket manufacturing technique used in South Africa. As this device requires only one visit and therefore decreased travel by the patients to the hospitals, it could be applicable to more amputees who cannot return to hospital post discharge.
Leijendekkers, Ruud A; van Hinte, Gerben; Frölke, Jan Paul; van de Meent, Hendrik; Nijhuis-van der Sanden, Maria W G; Staal, J Bart
2017-06-01
This study aimed to provide an overview of a) the used measurement instruments in studies evaluating effects on quality of life (QoL), function, activity and participation level in patients with a lower extremity amputation using bone-anchored prostheses compared to socket prostheses and b) the effects themselves. A systematic literature search was conducted in MEDLINE, Cochrane, EMBASE, CINAHL and Web of Science. Included studies compared QoL, function, activity and/or participation level in patients with bone-anchored or socket prostheses. A best-evidence synthesis was performed. Out of 226 studies, five cohort and two cross-sectional studies were eligible for inclusion, all had methodological shortcomings. These studies used 10 different measurement instruments and two separate questions to assess outcome. Bone-anchored prostheses were associated with better condition-specific QoL and better outcomes on several of the physical QoL subscales, outcomes on the physical bodily pain subscale were inconclusive. Outcomes on function and activity level increased, no change was found at participation level. The level of evidence was limited. There is a need for a standard set of instruments. There was limited evidence that bone-anchored prostheses resulted in higher QoL, function and activity levels than socket prostheses, in patients with socket-related problems. Implications for Rehabilitation Use of bone-anchored prostheses in combination with intensive outpatient rehabilitation may improve QoL, function and activity level compared with socket prosthesis use in patients with a transfemoral amputation and socket-related problems. All clinicians and researchers involved with bone-anchored prostheses should use and publish data on QoL, function, activity and participation level. There needs to be an agreement on a standard set of instruments so that interventions for patients with a lower extremity amputation are assessed consistently.
Taberner-Vallverdú, M; Sánchez-Garcés, M-Á; Gay-Escoda, C
2017-11-01
Dry socket is one of the most common complications that develops after the extraction of a permanent tooth, and its prevention is more effective than its treatment. Analyze the efficacy of different methods used in preventing dry socket in order to decrease its incidence after tooth extraction. A Cochrane and PubMed-MEDLINE database search was conducted with the search terms "dry socket", "prevention", "risk factors", "alveolar osteitis" and "fibrynolitic alveolitis", both individually and using the Boolean operator "AND". The inclusion criteria were: clinical studies including at least 30 patients, articles published from 2005 to 2015 and written in English. The exclusion criteria were case reports and nonhuman studies. 30 publications were selected from a total of 250. Six of the 30 were excluded after reading the full text. The final review included 24 articles: 9 prospective studies, 2 retrospective studies and 13 clinical trials. They were stratified according to their level of scientific evidence using SIGN criteria (Scottish Intercollegiate Guidelines Network). All treatments included in the review were aimed at decreasing the incidence of dry socket. Locally administering chlorhexidine or applying platelet-rich plasma reduces the likelihood of developing this complication. Antibiotic prescription does not avoid postoperative complications after lower third molar surgery. With regard to risk factors, all of the articles selected suggest that patient age, history of previous infection and the difficulty of the extraction are the most common predisposing factors for developing dry socket. There is no consensus that smoking, gender or menstrual cycles are risk factors. Taking the scientific quality of the articles evaluated into account, a level B recommendation has been given for the proposed-procedures in the prevention of dry socket.
Childers, Walter Lee; Siebert, Steven
2016-12-01
Limb movement between the residuum and socket continues to be an underlying factor in limb health, prosthetic comfort, and gait performance yet techniques to measure this have been underdeveloped. Develop a method to measure motion between the residual limb and a transtibial prosthetic socket. Single subject, repeated measures with mathematical modeling. The gait of a participant with transtibial amputation was recorded using a motion capture system using a marker set that included arrays on the anterior distal tibia and the lateral epicondyle of the femur. The proximal or distal translation, anterior or posterior translation, and angular movements were quantified. A random Monte Carlo simulation based on the precision of the motion capture system and a model of the bone moving under the skin explored the technique's accuracy. Residual limb tissue stiffness was modeled as a linear spring based on data from Papaioannou et al. Residuum movement relative to the socket went through ~30 mm, 18 mm, and 15° range of motion. Root mean squared errors were 5.47 mm, 1.86 mm, and 0.75° when considering the modeled bone-skin movement in the proximal or distal, anterior or posterior, and angular directions, respectively. The measured movement was greater than the root mean squared error, indicating that this method can measure motion between the residuum and socket. The ability to quantify movement between the residual limb and the prosthetic socket will improve prosthetic treatment through the evaluation of different prosthetic suspensions, socket designs, and motor control of the prosthetic interface. © The International Society for Prosthetics and Orthotics 2015.
Choi, Jisoo; Shin, Dong-Ah; Kim, Sohee
2017-03-15
A three-dimensional finite element model of intact lumbar spine was constructed and four surgical finite element models implanted with ball-and-socket artificial discs with four different radii of curvature were compared. To investigate biomechanical effects of the curvature of ball-and-socket artificial disc using finite element analysis. Total disc replacement (TDR) has been accepted as an alternative treatment because of its advantages over spinal fusion methods in degenerative disc disease. However, the influence of the curvature of artificial ball-and-socket discs has not been fully understood. Four surgical finite element models with different radii of curvature of ball-and-socket artificial discs were constructed. The range of motion (ROM) increased with decreasing radius of curvature in extension, flexion, and lateral bending, whereas it increased with increasing radius of curvature in axial torsion. The facet contact force was minimum with the largest radius of curvature in extension, flexion, and lateral bending, whereas it was maximum with the largest radius in axial torsion. It was also affected by the disc placement, more with posterior placement than anterior placement. The stress in L4 cancellous bone increased when the radius of curvature was too large or small. The geometry of ball-and-socket artificial disc significantly affects the ROM, facet contact force, and stress in the cancellous bone at the surgical level. The implication is that in performing TDR, the ball-and-socket design may not be ideal, as ROM and facet contact force are sensitive to the disc design, which may be exaggerated by the individual difference of anatomical geometry. N/A.
Metallurgy and Heat Treating. Welding Module 7. Instructor's Guide.
ERIC Educational Resources Information Center
Missouri Univ., Columbia. Instructional Materials Lab.
This guide is intended to assist vocational educators in teaching a three-unit module in metallurgy and heat treating. The module is part of a welding curriculum that has been designed to be totally integrated with Missouri's Vocational Instruction Management System. The basic principles of metallurgy and heat treatment and techniques for…
2017-10-01
significantly lower trim lines, without ischial containment compared with a traditional interface. However, these alternative designs could compromise...overall function compared to the standard of care interface design . Therefore the focus of this clinical trial is to determine if the DS and Sub-I...alternative interface designs will improve socket comfort, residual limb health and function compared to the standard of care IRC interface design . 15
Samandari, Mohammad Hasan; Haghighat, Abbas; Torabinia, Nakisa; Taghian, Mehdi; Sadri, Leyli; Naemy, Vahid
2016-01-01
Background: Plasma rich in growth factors (PRGF) and freeze-dried bone allograft (FDBA) are shown to promote bone healing. This study was aimed to histologically and histomorphometrically investigate the effect of combined use of PRGF and FDBA on bone formation, and compare it to FDBA alone and control group. Materials and Methods: The distal roots of the lower premolars were extracted bilaterally in four female dogs. Sockets were randomly divided into FDBA + PRGF, FDBA, and control groups. Two dogs were sacrificed after 2 weeks and two dogs were sacrificed after 4 weeks. Sockets were assessed histologically and histomorphometrically. Data were analyzed by Kruskal–Wallis test followed by Mann–Whitney U-tests utilizing the SPSS software version 20. P < 0.05 was considered statistically significant. Results: While the difference in density of fibrous tissue in three groups was not statistically significant (P = 0.343), the bone density in grafted groups was significantly higher than the control group (P = 0.021). The least decrease in all socket dimensions was observed in the FDBA group. However, these differences were only significant in coronal portion at week 4. Regarding socket dimensions and bone density, the difference between FDBA and FDBA+PRGF groups was not significant in middle and apical portions. Conclusion: The superiority of PRGF+FDBA overFDBA in socket preservation cannot be concluded from this experiment. PMID:27857769
Chu, Stephen J; Sarnachiaro, Guido O; Hochman, Mark N; Tarnow, Dennis P
2015-01-01
Immediate implant therapy involving implants placed into intact Type 1 extraction sockets has become a consistent clinical technique. The classification of Type 2 extraction sockets, where the mucosal tissues are present but there is a midfacial osseous dehiscence defect, has been described according to the extent of the buccal bone plate absence. The literature has offered different techniques in the treatment of Type 2 sockets; however, the extent of the defect has never been defined or delineated. In this article, the authors describe a subclassification of Type 2 sockets: Type 2A presents with a dehiscence defect roughly 5 mm to 6 mm from the free gingival margin (FGM) involving the coronal one-third of the labial bone plate; Type 2B presents with a dehiscence defect involving the middle one-third of the labial plate, approximately 7 mm to 9 mm from the FGM; and in Type 2C the dehiscence defect involves the apical one-third of the labial osseous plate roughly 10 mm or greater from the FGM. The authors also offer a protocol and technique employing immediate implant placement, guided bone regeneration, and bone graft containment with a custom two-piece healing abutment that can lead to consistent and satisfactory clinical outcomes in low-smile-line patients. The treatment protocol and sequence is outlined in a clinical case presentation involving a Type 2B socket.
Lee, Jungwon; Park, Dueun; Koo, Ki-Tae; Seol, Yang-Jo; Lee, Yong-Moo
2018-04-03
This review aimed to investigate the feasibility of immediate implant placement in infected extraction sockets. We performed electronic and manual searches up to March 2017 to obtain data from randomized controlled trials (RCTs) and nonrandomized controlled clinical trials (CCTs). Using a fixed-effects model to assess the difference in survival rate (primary outcome), we evaluated the risk difference for immediate implant placement in infected and non-infected sites. We estimated the weighted mean differences (WMDs) of the change in marginal bone loss (MBL), probing depth (PD), modified bleeding index (mBI), marginal gingival level (MGL) and width of keratinized gingiva (WKG) at baseline and latest follow-up. In total, five studies (0 RCT, five CCTs) were included in the systematic review and three studies were included in the meta-analysis. The risk difference for immediate implant placement in an infected extraction socket compared with that in a non-infected socket was -0.02. WMDs for MBL, PD, mBI, MGL and WKG between the two groups were 0.32, 0.12, 0.07, -0.06, 0.20 and 0.51, respectively. No statistical differences were observed between the two groups, except for the change in WKG. Implants can be placed in infected extraction sockets after thorough socket debridement. For aesthetics, WKG should be considered when performing immediate implant placement in infected sites.
Tomasi, Cristiano; Donati, Mauro; Cecchinato, Denis; Szathvary, Isacco; Corrà, Enrico; Lindhe, Jan
2018-05-01
To examine if (i) characteristics of the fresh extraction socket site influenced subsequent dimensional alterations and (ii) placement of deproteinized bovine mineral in the socket affected volumetric change during healing. Twenty seven subjects and 28 extraction sites were included. Immediately after the removal of the tooth and after 6 months of healing, stone and virtual models of the jaw were produced. A cone beam computerized tomography scan was obtained immediately after extraction and the thickness of the buccal bone wall at the extraction site was measured. Extraction sites were randomly assigned to test or control group. In the test group, extraction sockets were filled with deproteinized bone mineral and covered with a collagen membrane. In the control group, only a collagen membrane was placed. The thickness of the buccal bone wall at the extraction site influenced the amount of volume reduction that occurred. Socket grafting influenced the degree of ridge diminution only at sites where the buccal bone wall was thin (≤ 1 mm). A graft comprised of collagen-enriched deproteinized bovine bone mineral, placed to fill extraction sockets failed to influence the overall diminution of the ridge that occurred during healing. The thickness of the buccal bone wall apparently had a significant influence on volumetric alterations of the edentulous ridge following tooth extraction. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
A pressure and shear sensor system for stress measurement at lower limb residuum/socket interface.
Laszczak, P; McGrath, M; Tang, J; Gao, J; Jiang, L; Bader, D L; Moser, D; Zahedi, S
2016-07-01
A sensor system for measurement of pressure and shear at the lower limb residuum/socket interface is described. The system comprises of a flexible sensor unit and a data acquisition unit with wireless data transmission capability. Static and dynamic performance of the sensor system was characterised using a mechanical test machine. The static calibration results suggest that the developed sensor system presents high linearity (linearity error ≤ 3.8%) and resolution (0.9 kPa for pressure and 0.2 kPa for shear). Dynamic characterisation of the sensor system shows hysteresis error of approximately 15% for pressure and 8% for shear. Subsequently, a pilot amputee walking test was conducted. Three sensors were placed at the residuum/socket interface of a knee disarticulation amputee and simultaneous measurements were obtained during pilot amputee walking test. The pressure and shear peak values as well as their temporal profiles are presented and discussed. In particular, peak pressure and shear of approximately 58 kPa and 27 kPa, respectively, were recorded. Their temporal profiles also provide dynamic coupling information at this critical residuum/socket interface. These preliminary amputee test results suggest strong potential of the developed sensor system for exploitation as an assistive technology to facilitate socket design, socket fit and effective monitoring of lower limb residuum health. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.
Bramanti, Ennio; Norcia, Antonio; Cicciù, Marco; Matacena, Giada; Cervino, Gabriele; Troiano, Giuseppe; Zhurakivska, Khrystyna; Laino, Luigi
2018-06-01
The aim of this randomized controlled trial was to evaluate the survival rate, the marginal bone level, and the aesthetic outcome; at 3 years' follow-up, of dental implants placed into a high-esthetic aesthetic zone by comparing 2 techniques of postextraction implant with immediate loading: the socket shied technique and the conventional insertion technique.Several clinical studies suggested that the avulsion of a dental element causes dimensional alterations of both soft and hard tissues at the postextractive site. To increase the aesthetic outcomes, the "socket-shield technique" has been proposed. This method involves maintaining the vestibular root portion and immediate insertion of the dental implant in close proximity to the root.Patients enrolled in this study were randomized to receive a postextraction implant in the aesthetic zone, either with the socket shied technique or with the conventional insertion technique. Implant survival, marginal bone level, and the pink aesthetic score were the outcomes evaluated.Implant survival rate was 100% in both the groups at 3 years. Implants inserted with the socket shield technique showed better values of both marginal bone level and pink aesthetic score (P < 0.05).Although such preliminary results need to be further confirmed, the socket shield technique seems to be a safe surgical technique that allows an implant rehabilitation characterized by better aesthetic outcomes.
Fickl, Stefan; Schneider, David; Zuhr, Otto; Hinze, Marc; Ender, Andreas; Jung, Ronald E; Hürzeler, Markus B
2009-05-01
The aim of the study was to volumetrically assess alterations of the ridge contour after socket preservation and buccal overbuilding. In five beagle dogs, four extraction sites were subjected to one of the following treatments: Tx 1: The socket was filled with BioOss Collagen and covered with a free gingival autograft from the palate (SP). Tx 2: The buccal bone plate was forced into a buccal direction using a manual bone spreader and SP was performed. Tx 3: The buccal bone plate was forced into a buccal direction using a manual bone spreader; SP was performed. Tx 4: The socket was filled with BioOss Collagen and a combined free gingival/connective tissue graft was used to cover the socket and for buccal tissue augmentation. Impressions were obtained at baseline, 2 weeks and 4 months post-operatively. Casts were optically scanned and superimposed in one common coordinate system. Using digital image analysis, the volumetric differences per area among the different treatment time points and among the treatment groups were calculated. Four months after tooth extraction, no statistically significant differences with regard to the buccal volume per area could be assessed among the treatment groups. Overbuilding the buccal aspect in combination with socket preservation is not a suitable technique to compensate for the alterations after tooth extraction.
Socket with built-in valves for the interconnection of microfluidic chips to macro constituents.
Yang, Zhen; Maeda, Ryutaro
2003-09-26
This paper reports a prototype for a standard connector between a microfluidic chip and the macro world. This prototype demonstrate a fully functioning socket for a microchip to access the outside world by means of fluids, data signals and energy supply. It supports up to 10 channels for the input and output of liquids or gases, as well as compressed air or vacuum lines for pneumatic power lines. The socket has built-in valves for each flow channel. It also contains 28 pins for the connection of electrical signals and power. Built-in valves make it possible to control the flow in each channel independently. A chip ( 11.0 x 11.0 x 0.9 mm) can be mounted into or dismounted from the socket with one touch. The fluidic connectors of the socket are designed to contact vertically on the top of chip. And the electrical connectors (the spring array) of that physically support the chip and contact lead pads at the bottom of chip. No adhesives or solders are used at any contact points. The pressure limit for the connection of working fluids was 0.2 MPa and the current limit for the electrical connections was 1 A. This socket supports both serial and parallel processing applications. It exhibits great potential for developing microfluidic systems efficiently.
... of the joint, is called the condyle. The socket is called the articular fossa. Between the condyle ... that is located between the jawbone and the socket. A displaced disk may produce clicking or popping ...
Cordasco, Frank A
2018-05-01
I believe that the distal femoral approach for anterior cruciate ligament reconstruction in the skeletally immature athlete with 3 to 6 years of remaining growth is best performed with an all-inside, all-epiphyseal technique using sockets rather than an outside-in approach creating tunnels. A shorter socket rather than a longer tunnel exposes a smaller surface area of the lateral distal femoral physis to potential compromise and resultant valgus malalignment. In addition, exiting the lateral femoral aspect of the epiphysis with a full-diameter tunnel as compared with a smaller diameter drill hole used to prepare a socket places the posterior articular cartilage, the lateral collateral ligament and anterolateral ligament footprints, and the popliteus tendon insertion at risk. My preference for sockets is also related to my belief that they provide a superior biologic milieu for graft incorporation compared with a full-length tunnel with the attendant violation of the lateral femoral cortex of the epiphysis. Copyright © 2018 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Al-Fakih, Ebrahim; Arifin, Nooranida; Pirouzi, Gholamhossein; Mahamd Adikan, Faisal Rafiq; Shasmin, Hanie Nadia; Abu Osman, Noor Azuan
2017-08-01
This paper presents a fiber Bragg grating (FBG)-instrumented prosthetic silicone liner that provides cushioning for the residual limb and can successfully measure interface pressures inside prosthetic sockets of lower-limb amputees in a simple and practical means of sensing. The liner is made of two silicone layers between which 12 FBG sensors were embedded at locations of clinical interest. The sensors were then calibrated using a custom calibration platform that mimics a real-life situation. Afterward, a custom gait simulating machine was built to test the liner performance during an amputee's simulated gait. To validate the findings, the results were compared to those obtained by the commonly used F-socket mats. As the statistical findings reveal, both pressure mapping methods measured the interface pressure in a consistent way, with no significant difference (P-values ≥0.05). This pressure mapping technique in the form of a prosthetic liner will allow prosthetics professionals to quickly and accurately create an overall picture of the interface pressure distribution inside sockets in research and clinical settings, thereby improving the socket fit and amputee's satisfaction.
The efficacy of hyaluronic acid in postextraction sockets of impacted third molars: A pilot study.
Yilmaz, N; Demirtas, N; Kazancioglu, H O; Bayer, S; Acar, A H; Mihmanli, A
2017-12-01
This study aims to evaluate the effectiveness of local hyaluronic acid (HA) administration to surgically remove impacted third molar sockets and measure pain, swelling, and trismus. The study included a total of 25 healthy patients aged 18-29 years with asymptomatic bilaterally impacted lower third molars. All cases have been performed under local anesthesia. In the study group, 0.8% HA (Gengigel®) was applied in the postextraction sockets of the right third molars and in the control group nothing was applied to the extraction sockets of the left third molars. Postoperative pain, trismus, and swelling were evaluated on the 1st, 3rd, and 7th postoperative days. No difference was determined between groups in facial swelling and maximum mouth opening. However, the amount of pain significantly reduced in HA groups according to visual analog scale (P = 0.001). The results of this study showed that HA can produce an analgesic action in postextraction sockets after surgical removal of impacted teeth and therefore it has a clinical benefit to reduce usage of nonsteroidal anti-inflammatory drugs after dentoalveolar surgery.
Hamada, Yusuke; Prabhu, Srividya; John, Vanchit
2016-01-01
As implant therapy becomes more commonplace in daily practice, preservation and preparation of edentulous sites are key. Many times, however, implant therapy may not be considered at the time of tooth extraction and additional measures are not taken to conserve the edentulous site. While the healing process in extraction sockets has been well investigated and bone fill can be expected, there are cases where even when clinicians perform thorough debridement of the sockets, connective tissue infiltration into the socket can occur. This phenomenon, known as "erratic healing," may be associated with factors that lead to peri-implant disease and should be appropriately managed and treated prior to surgical implant placement. This case report describes the successful management of an erratic healing extraction socket in a 62-year-old Caucasian male patient with chronic periodontitis and the outcomes of an evidence-based treatment protocol performed prior to implant therapy. Careful preoperative analysis and cone beam computed tomography imaging can help detect signs of impaired healing in future implant sites and prevent surgical complications.
Prabhu, Srividya
2016-01-01
As implant therapy becomes more commonplace in daily practice, preservation and preparation of edentulous sites are key. Many times, however, implant therapy may not be considered at the time of tooth extraction and additional measures are not taken to conserve the edentulous site. While the healing process in extraction sockets has been well investigated and bone fill can be expected, there are cases where even when clinicians perform thorough debridement of the sockets, connective tissue infiltration into the socket can occur. This phenomenon, known as “erratic healing,” may be associated with factors that lead to peri-implant disease and should be appropriately managed and treated prior to surgical implant placement. This case report describes the successful management of an erratic healing extraction socket in a 62-year-old Caucasian male patient with chronic periodontitis and the outcomes of an evidence-based treatment protocol performed prior to implant therapy. Careful preoperative analysis and cone beam computed tomography imaging can help detect signs of impaired healing in future implant sites and prevent surgical complications. PMID:27807485
NASA Astrophysics Data System (ADS)
Tabik, S.; Romero, L. F.; Mimica, P.; Plata, O.; Zapata, E. L.
2012-09-01
A broad area in astronomy focuses on simulating extragalactic objects based on Very Long Baseline Interferometry (VLBI) radio-maps. Several algorithms in this scope simulate what would be the observed radio-maps if emitted from a predefined extragalactic object. This work analyzes the performance and scaling of this kind of algorithms on multi-socket, multi-core architectures. In particular, we evaluate a sharing approach, a privatizing approach and a hybrid approach on systems with complex memory hierarchy that includes shared Last Level Cache (LLC). In addition, we investigate which manual processes can be systematized and then automated in future works. The experiments show that the data-privatizing model scales efficiently on medium scale multi-socket, multi-core systems (up to 48 cores) while regardless of algorithmic and scheduling optimizations, the sharing approach is unable to reach acceptable scalability on more than one socket. However, the hybrid model with a specific level of data-sharing provides the best scalability over all used multi-socket, multi-core systems.
Investigation of welded interconnection of large area wraparound contacted silicon solar cells
NASA Technical Reports Server (NTRS)
Lott, D. R.
1984-01-01
An investigation was conducted to evaluate the welding and temperature cycle testing of large area 5.9 x 5.9 wraparound silicon solar cells utilizing printed circuit substrates with SSC-155 interconnect copper metals and the LMSC Infrared Controlled weld station. An initial group of 5 welded modules containing Phase 2 developmental 5.9 x 5.9 cm cells were subjected to cyclical temperatures of + or 80 C at a rate of 120 cycles per day. Anomalies were noted in the adhesion of the cell contact metallization; therefore, 5 additional modules were fabricated and tested using available Phase I cells with demonstrated contact integrity. Cycling of the later module type through 12,000 cycles indicated the viability of this type of lightweight flexible array concept. This project demonstrated acceptable use of an alternate interconnect copper in combination with large area wraparound cells and emphasized the necessity to implement weld pull as opposed to solder pull procedures at the cell vendors for cells that will be interconnected by welding.
... This type of implant is an artificial hip socket that is created by fitting a metal ball ... particles (ions) can get released into the hip socket and sometimes the bloodstream, causing cobalt toxicity. This ...
... the opening at the end of the shoulder blade, called the socket. This type of joint allows ... head. The socket part (glenoid) of your shoulder blade will be replaced with a smooth plastic shell ( ...
Vane segment support and alignment device
DOE Office of Scientific and Technical Information (OSTI.GOV)
McLaurin, L.D.; Sizemore, J.D.
1999-07-13
A support and alignment assembly for supporting and aligning a vane segment is provided. The support and alignment assembly comprises a torque plate which defines an opening for receiving an eccentric pin and a locking end member for receiving a lock socket member. An eccentric pin adjustably supported by the torque plate opening for supporting and aligning a vane segment is provided. A lock socket member adapted to securely receive the eccentric pin and rotated therewith, and adjustably engage the torque plate locking end is provided. The lock socket member receives the eccentric pin, such that when the eccentric pinmore » is adjusted to align the vane segment, the lock socket member engages the torque plate locking end to secure the vane segment in the desired position. 5 figs.« less
Hybrid/Tandem Laser-Arc Welding of Thick Low Carbon Martensitic Stainless Steel Plates =
NASA Astrophysics Data System (ADS)
Mirakhorli, Fatemeh
High efficiency and long-term life of hydraulic turbines and their assemblies are of utmost importance for the hydropower industry. Usually, hydroelectric turbine components are made of thick-walled low carbon martensitic stainless steels. The assembly of large hydroelectric turbine components has been a great challenge. The use of conventional welding processes involves typical large groove design and multi-pass welding to fill the groove which exposes the weld to a high heat input creating relatively large fusion zone and heat affected zone. The newly-developed hybrid/tandem laser-arc welding technique is believed to offer a highly competitive solution to improve the overall hydro-turbine performance by combining the high energy density and fast welding speed of the laser welding technology with the good gap bridging and feeding ability of the gas metal arc welding process to increase the productivity and reduce the consumable material. The main objective of this research work is to understand different challenges appearing during hybrid laser-arc welding (HLAW) of thick gauge assemblies of low carbon 13%Cr- 4%Ni martensitic stainless steel and find a practical solution by adapting and optimizing this relatively new welding process in order to reduce the number of welding passes necessary to fill the groove gap. The joint integrity was evaluated in terms of microstructure, defects and mechanical properties in both as-welded and post-welded conditions. A special focus was given to the hybrid and tandem laser-arc welding technique for the root pass. Based on the thickness of the low carbon martensitic stainless steel plates, this work is mainly focused on the following two tasks: • Single pass hybrid laser-arc welding of 10-mm thick low carbon martensitic stainless steel. • Multi-pass hybrid/tandem laser-arc welding of 25-mm thick martensitic stainless steel.
Solid State Welding Development at Marshall Space Flight Center
NASA Technical Reports Server (NTRS)
Ding, Robert J.; Walker, Bryant
2012-01-01
What is TSW and USW? TSW is a solid state weld process consisting of an induction coil heating source, a stir rod, and non-rotating containment plates Independent heating, stirring and forging controls Decouples the heating, stirring and forging process elements of FSW. USW is a solid state weld process consisting of an induction coil heating source, a stir rod, and a non-rotating containment plate; Ultrasonic energy integrated into non-rotating containment plate and stir rod; Independent heating, stirring and forging controls; Decouples the heating, stirring and forging process elements of FSW.
Digital Radiography Qualification of Tube Welding
NASA Technical Reports Server (NTRS)
Carl, Chad
2012-01-01
The Orion Project will be directing Lockheed Martin to perform orbital arc welding on commodities metallic tubing as part of the Multi Purpose Crew Vehicle assembly and integration process in the Operations and Checkout High bay at Kennedy Space Center. The current method of nondestructive evaluation is utilizing traditional film based x-rays. Due to the high number of welds that are necessary to join the commodities tubing (approx 470), a more efficient and expeditious method of nondestructive evaluation is desired. Digital radiography will be qualified as part of a broader NNWG project scope.
Automatic programming of arc welding robots
NASA Astrophysics Data System (ADS)
Padmanabhan, Srikanth
Automatic programming of arc welding robots requires the geometric description of a part from a solid modeling system, expert weld process knowledge and the kinematic arrangement of the robot and positioner automatically. Current commercial solid models are incapable of storing explicitly product and process definitions of weld features. This work presents a paradigm to develop a computer-aided engineering environment that supports complete weld feature information in a solid model and to create an automatic programming system for robotic arc welding. In the first part, welding features are treated as properties or attributes of an object, features which are portions of the object surface--the topological boundary. The structure for representing the features and attributes is a graph called the Welding Attribute Graph (WAGRAPH). The method associates appropriate weld features to geometric primitives, adds welding attributes, and checks the validity of welding specifications. A systematic structure is provided to incorporate welding attributes and coordinate system information in a CSG tree. The specific implementation of this structure using a hybrid solid modeler (IDEAS) and an object-oriented programming paradigm is described. The second part provides a comprehensive methodology to acquire and represent weld process knowledge required for the proper selection of welding schedules. A methodology of knowledge acquisition using statistical methods is proposed. It is shown that these procedures did little to capture the private knowledge of experts (heuristics), but helped in determining general dependencies, and trends. A need was established for building the knowledge-based system using handbook knowledge and to allow the experts further to build the system. A methodology to check the consistency and validity for such knowledge addition is proposed. A mapping shell designed to transform the design features to application specific weld process schedules is described. A new approach using fixed path modified continuation methods is proposed in the final section to plan continuously the trajectory of weld seams in an integrated welding robot and positioner environment. The joint displacement, velocity, and acceleration histories all along the path as a function of the path parameter for the best possible welding condition are provided for the robot and the positioner to track various paths normally encountered in arc welding.
... top of the thighbone (femoral head) and its socket (acetabulum) in the pelvic bone. It can be ... hip, the femoral head rests comfortably in its socket. In babies with DDH, the femoral head moves ...
... and pituitary gland for neurosurgeons, or to the orbits (eye sockets) for certain ophthalmology procedures. Each individual ... that the sinuses are located next to the orbits (eye sockets) and directly beneath the bottom of ...
2016-12-01
of the frame from the combined image files and ensure total contact between the frame geometry, ultimately modeled independently as a solid, and...fitting with a rigid PETG check socket to ensure correct volumes and total contact at the distal end has been achieved, a second check socket can be...from dynamically conforming to changes in residual limb shape and volume during gait (Sanders, 2009). The ensuing separation (i.e. loss of contact
Ball-and-Socket Joint Can Be Disassembled
NASA Technical Reports Server (NTRS)
Totah, R. S.
1982-01-01
Ball-and-socket joint originally developed for construction of large platforms in zero g could be used in such Earth-based temporary structures as scaffolding, camping equipment, tent posts, trade shows and displays. New joint consists of a socket mounted on central hub or union and ball-ended bolt or fitting mounted at end of a column or any structural member. Unit is self-contained, requires no loose hardware and is engaged or disengaged without tools manually, or remotely by a manipulator.
Alzahrani, Ahmed Abdullah; Murriky, Afraa; Shafik, Sami
2017-10-01
The aim of this study was to evaluate clinically and radiographically, extraction socket healing using autologous platelet rich fibrin (PRF). Twenty-four subjects needing single tooth simple extractions were selected. Twenty-four extraction sockets were divided into test group (PRF, n = 12) and control group (blood clot, n = 12). PRF was prepared with blood drawn from individuals after extraction using standard technique. PRF was placed in test group sockets followed by pressure application and figure 8 sutures. Sockets in control group were allowed to heal in the presence of blood clot and received a figure 8 suture. Ridge width was assessed using cast analysis with the help of acrylic stent and a pair of calipers. Radiographic analysis of socket surface area was performed using computer graphic software program. The clinical follow up assessments were performed at 1, 4 and 8 weeks. Collected data was assessed using ANOVA and multiple comparisons test. Subjects were aged between 25 and 50 (mean 37.8) years, including 15 females. The mean horizontal ridge width for sockets in the test group were 11.70 ± 2.37 mm, 11.33 ± 2.30 mm and 10.97 ± 2.33 mm at 1, 4 and 8 weeks respectively. Ridge width proportions were significantly higher among test group as compared to control group between baseline to 4 and 8 weeks respectively. The mean radiographic bone fill (RBF) percentage in the test group, was 74.05 ± 1.66%, 81.54 ± 3.33% and 88.81 ± 1.53% at 1, 4 and 8 weeks respectively. The mean RBF was significantly higher in the test group than control group at all time intervals. The study outcomes demonstrate that the use of PRF accelerate socket wound healing after tooth extraction as noticed by increased bone fill and reduced alveolar bone width resorption using clinical and radiographic methods.
Rudakov, M L
2000-01-01
Method of secondary sources (method of integral equations) was applied to calculate specific absorbed intensity in hands of operators working at non-shielded high-frequency (27.12 Mhz) welding devices. The authors present calculations for "female" and "male" hand sizes, give recommendations on lower level of specific absorption.
Print Reading, Layout and Fit-Up. Welding Module 2. Instructor's Guide.
ERIC Educational Resources Information Center
Missouri Univ., Columbia. Instructional Materials Lab.
This guide is intended to assist vocational educators in teaching a five-unit module in print reading, layout, and fit-up. The module is part of a welding curriculum that has been designed to be totally integrated with Missouri's Vocational Instruction Management System. The following topics are covered in the module: reading basic prints and…
Plasma Cutting and Carbon-Arc Cutting. Welding Module 8. Instructor's Guide.
ERIC Educational Resources Information Center
Missouri Univ., Columbia. Instructional Materials Lab.
This guide is intended to assist vocational educators in teaching the two units of a module in operating plasma cutting and carbon-arc cutting equipment. The module is part of a welding curriculum that has been designed to be totally integrated with Missouri's Vocational Instruction Management System. The materials included in the module have been…
Anzehaee, Mohammad Mousavi; Haeri, Mohammad
2011-07-01
New estimators are designed based on the modified force balance model to estimate the detaching droplet size, detached droplet size, and mean value of droplet detachment frequency in a gas metal arc welding process. The proper droplet size for the process to be in the projected spray transfer mode is determined based on the modified force balance model and the designed estimators. Finally, the droplet size and the melting rate are controlled using two proportional-integral (PI) controllers to achieve high weld quality by retaining the transfer mode and generating appropriate signals as inputs of the weld geometry control loop. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.
Acceptance criteria for welds in ASTM A106 grade B steel pipe and plate
NASA Technical Reports Server (NTRS)
Hudson, C. M.; Wright, D. B., Jr.; Leis, B. N.
1986-01-01
Based on the RECERT Program findings, NASA-Langley funded a fatigue study of code-unacceptable welds. Usage curves were developed which were based on the structural integrity of the welds. The details of this study are presented in NASA CR-178114. The information presented is a condensation and reinterpretation of the information in NASA CR-178114. This condensation and reinterpretation generated usage curves for welds having: (1) indications 0.20 -inch deep by 0.40-inch long, and (2) indications 0.195-inch deep by 8.4-inches long. These curves were developed using the procedures used in formulating the design curves in Section VIII, Division 2 of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code.
Seifi, Massoud; Atri, Faezeh; Yazdani, Mohammad Masoud
2014-01-01
Low- level laser therapy has been used to stimulate the orthodontic tooth movements (OTM) previously. Furthermore, in the orthodontic treatments accompanying tooth extractions, the adjacent teeth move towards the extraction sites and close the space in some cases. Then, the adjacent tooth movements must be prevented in the treatments requiring space. Laser stimulates and at some doses decelerates tooth movement; it also improves healing process and enhances osteogenesis. Hence, it can prevent movement by osteogenesis adjacent to the tooth. The present study investigated the effects of low-level laser therapy on the OTM and root resorption following artificial socket preservation. In this experimental animal trial, 16 male albino rabbits were selected with similar characteristics and randomly divided in two groups. Under general anesthesia, an artificial socket, 8 mm in height, was created in the mesial aspect of the first premolars of the rabbits and filled with demineralized freeze dried bone allograft (DFDBA). The first premolars were connected to the incisors using nickel titanium coil springs. In experimental group, gallium-aluminum-arsenide (GaAlAs) laser was irritated mesial to first premolar where artificial socket was created continuously (808 nm). The cycle was 10 days irritation, 14 days rest, 10 days irritation, 14 days rest (Biostimulation mode). Control group was not laser irradiated. All animals were sacrificed after 48 days and the distance between the distal aspect of the first premolars, and the mesial surface of the second premolars was measured with leaf gauge. The specimens underwent histological assessments. Integrity of root and its resorption was observed under microscope calibration. The size of resorption lacunae was calculated in mm(2). Normality of data was proved according to Kolmogorov-Smirnov analysis, and Student's t-test was done. P value less than 0.05 was considered as significant. The mean OTM were 5.68 ± 1.21 mm in the control group and 6.0 ± 0.99 mm in the laser irradiated teeth with no statistically significant differences(P > 0.75). The mean root resorption was 1.61 ± 0.43 mm(2) and 0.18 ± 0.07 mm(2) in the control and experimental groups respectively being significantly lower in the laser irradiated teeth (P < 0.0001). The findings of the present study show that GaAlAs irradiation together with the application of DFDBA led to limited amount of the stimulated OTM. The laser beam irradiation in combination with alloplastic materials used for socket preservation could reduce the degree of root resorption significantly.
Dislocated Shoulder: Symptoms and Causes
... arm bone pops out of the cup-shaped socket that's part of your shoulder blade. The shoulder ... your upper arm bone out of your shoulder socket. Partial dislocation — in which your upper arm bone ...
Bakhshalian, Neema; Freire, Marcelo; Min, Seiko; Wu, Ivy; Zadeh, Homayoun H
A total of 68 extraction sockets were grafted with anorganic bovine bone mineral and covered by dense polytetrafluoroethylene membrane. Quantitative analysis of three-dimensional microcomputed tomography imaging of core samples retrieved after a mean of 21.0 ± 14.2 weeks revealed 40.1% bone volume fraction (bone volume [BV]/total volume [TV]) and 12% residual graft. Evidence of de novo bone formation was observed in the form of discrete islands of newly formed bone in direct apposition to graft particles, separated from parent bone. Anterior sockets exhibited a significantly higher percentage of residual graft compared to premolar sockets (P = .05). The BV/TV and percentage of residual graft correlated well with histomorphometric analysis of the same sites, but not with implant outcomes.
The possible nature of socket stars in H II regions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Castelaz, M.W.
1990-01-01
Close inspection of faint stars (V of about 14 mag) in H II regions show that they appear to be surrounded by circumstellar envelopes of about 10 arcsecs in diameter (as reported by Feibelman in 1989). The present premise is that the sockets are envelopes of obscuring dust which should emit a measurable amount of infrared radiation based on a simple thermal equilibrium model. A search of literature shows that, of 36 socket stars listed by Feibelman, 17 have been measured in the infrared. Of the 17, 14 show excess IR emission. This is very strong evidence that the socketmore » stars are really stars with circumstellar envelopes. Socket stars may be a new type of astronomical object or well-known astronomical objects in environments or evolutionary states not previously seen. 22 refs.« less
Rakhshan, V
2018-04-30
Dry socket is a common complication of dental extraction, especially extraction of third molars. Knowledge of the frequent risk factors of alveolitis osteitis is useful in determining high-risk patients, treatment planning, and preparing the patients mentally. The aim of this narrative review was to summarize the common risk factors of dry socket. Unlike surgery difficulty, surgeon's experience, oral contraception use, and oral hygiene which showed stronger evidence, the influences of age, gender, and smoking were rather inconclusive. The case of female or oral contraceptive effect might relate mainly to estrogen levels (when it comes to dry socket) which can differ considerably from case to case. Many risk factors might be actually a combination of various independent variables, which should be targeted instead, in more comprehensive designs. Copyright © 2018 Elsevier Masson SAS. All rights reserved.
Robin, Brett N; Lubowitz, James H
2014-10-01
Anterior cruciate ligament (ACL) femoral socket techniques have distinct advantages and disadvantages when considering the following techniques: transtibial, anteromedial portal, outside-in, and outside-in retroconstruction. There is no one perfect technique and we have an incomplete understanding of anatomical, biomechanical, isometry, stability, and clinical outcomes. Our primary focus is transtibial technique for creating the ACL femoral socket. Advantages include less invasive, isometric graft placement, stable Lachman exam, and minimal graft impingement with the tunnel and notch. Disadvantages include nonanatomic vertical graft placement that can cause rotational instability and positive pivot shift, interference screw divergence, graft-tunnel length mismatch, femoral socket constraint, posterior cruciate ligament impingement, and a short, oblique tibial tunnel that may undermine the medial plateau in an attempt to achieve anatomic ACL reconstruction. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Liu, Chang; Wu, Zhe; Sun, Hong-chen
2009-01-01
Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) in the tooth sockets of rat. Methodology Forty-eight male Wistar rats were randomly divided into experimental and control groups (n=24). Polylactic acid/polyglycolic acid copolymer carriers, with or without simvastatin, were implanted into extraction sockets of right mandibular incisors. The expression of TGF-β1, BMP-2 and VEGF mRNA was determined by in situ hybridization in the tooth extraction socket at five days, one week, two weeks and four weeks after implantation. Results The fusiform stroma cells in the tooth extraction socket began to express TGF-β1, BMP-2 and VEGF mRNA in both experimental and control groups from one week after tooth extraction until the end of experiment. The expression of TGF-β1 and BMP-2 mRNA in the experimental group was significantly up-regulated after one, two and four weeks, and expression of VEGF mRNA was significantly increased after one and two weeks compared with that in the control group. Conclusion The findings indicate that local administration of simvastatin can influence alveolar bone remodeling by regulating the expression of a school of growth factors which are crucial to osteogenesis in the tooth extraction socket. PMID:20687301
Versatile Friction Stir Welding/Friction Plug Welding System
NASA Technical Reports Server (NTRS)
Carter, Robert
2006-01-01
A proposed system of tooling, machinery, and control equipment would be capable of performing any of several friction stir welding (FSW) and friction plug welding (FPW) operations. These operations would include the following: Basic FSW; FSW with automated manipulation of the length of the pin tool in real time [the so-called auto-adjustable pin-tool (APT) capability]; Self-reacting FSW (SRFSW); SR-FSW with APT capability and/or real-time adjustment of the distance between the front and back shoulders; and Friction plug welding (FPW) [more specifically, friction push plug welding] or friction pull plug welding (FPPW) to close out the keyhole of, or to repair, an FSW or SR-FSW weld. Prior FSW and FPW systems have been capable of performing one or two of these operations, but none has thus far been capable of performing all of them. The proposed system would include a common tool that would have APT capability for both basic FSW and SR-FSW. Such a tool was described in Tool for Two Types of Friction Stir Welding (MFS- 31647-1), NASA Tech Briefs, Vol. 30, No. 10 (October 2006), page 70. Going beyond what was reported in the cited previous article, the common tool could be used in conjunction with a plug welding head to perform FPW or FPPW. Alternatively, the plug welding head could be integrated, along with the common tool, into a FSW head that would be capable of all of the aforementioned FSW and FPW operations. Any FSW or FPW operation could be performed under any combination of position and/or force control.
NASA Astrophysics Data System (ADS)
Harooni, Masoud; Carlson, Blair; Kovacevic, Radovan
2014-05-01
The effect of surface oxide layer existing at the lap-joint faying surface of magnesium sheets is investigated on the keyhole dynamics of the weld pool and weld bead qualities. It is observed that by removing the oxide layer from the faying surface of the lap joint, a high quality weld can be achieved in the laser welding process. However, the presence of an oxide layer deteriorates the quality of the weld by forming pores at the interface of the two overlapped sheets. The purpose of this paper is to identify the correlation between the integrity of the weld and the interaction between the laser and material. A spectroscopy sensor was applied to detect the spectra emitted from a plasma plume during the laser welding of AZ31B magnesium alloy in a zero-gap lap joint configuration. The electron temperature was calculated by applying a Boltzmann plot method based on the detected spectra, and the correlation between the pore formation and the spectral signals was studied. The laser molten pool and the keyhole condition were monitored in real-time by a high speed charge-coupled device (CCD) camera. A green laser was used as an illumination source in order to detect the influence of the oxide layer on the dynamic behavior of the molten pool. Results revealed that the detected spectrum and weld defects had a meaningful correlation for real-time monitoring of the weld quality during laser welding of magnesium alloys.
Strategies for risk assessment and control in welding: challenges for developing countries.
Hewitt, P J
2001-06-01
Metal arc welding ranges from primitive (manual) to increasingly complex automated welding processes. Welding occupies 1% of the labour force in some industrialised countries and increasing knowledge of health risks, necessitating improved assessment strategies and controls have been identified by the International Institute of Welding (IIW), ILO, WHO and other authoritative bodies. Challenges for developing countries need to be addressed. For small scale production and repair work, predominantly by manual metal arc on mild steel, the focus in developing economies has correctly been on control of obvious physical and acute health affects. Development introduces more sophisticated processes and hazards. Work pieces of stainless steel and consumables with chromium, nickel and manganese constituents are used with increasingly complex semi-manual or automated systems involving variety of fluxes or gasses. Uncritical adoption of new welding technologies by developing countries potentiates future health problems. Control should be integral at the design stage, otherwise substantive detriments and later costs can ensue. Developing countries need particular guidance on selection of the optimised welding consumables and processes to minimise such detriments. The role of the IIW and the MFRU are described. Applications of occupational hygiene principals of prevention and control of welding fume at source by process modification are presented.
Review: magnetically assisted resistance spot welding
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Y. B.; Li, D. L.; Lin, Z. Q.
2016-02-25
Currently, the use of advanced high strength steels (AHSSs) is the most cost effective means of reducing vehicle body weight and maintaining structural integrity at the same time. However, AHSSs present a big challenge to the traditional resistance spot welding (RSW) widely applied in automotive industries because the rapid heating and cooling procedures during RSW produce hardened weld microstructures, which lower the ductility and fatigue properties of welded joints and raise the probability of interfacial failure under external loads. Changing process parameters or post-weld heat treatment may reduce the weld brittleness, but those traditional quality control methods also increase energymore » consumption and prolong cycle time. In recent years, a magnetically assisted RSW (MA-RSW) method was proposed, in which an externally applied magnetic field would interact with the conduction current to produce a Lorentz force that would affect weld nugget formation. This paper is a review of an experimental MA-RSW platform, the mode of the external magnetic field and the mechanism that controls nugget shape, weld microstructures and joint performance. In conclusion, the advantages of the MA-RSW method in improving the weldability of AHSSs are given, a recent application of the MA-RSW process to light metals is described and the outlook for the MA-RSW process is presented.« less
Haughie, David W; Buckley, C Paul; Wu, Junjie
2006-07-01
In Part 2 of a study of welding of ultra-high molecular weight polyethylene (UHMWPE), experiments were conducted to measure the interfacial fracture energy of butt welds, for various welding times and temperatures above the melting point. Their toughness was investigated at 37 degrees C in terms of their fracture energy, obtained by adapting the essential work of fracture (EWF) method. However, a proportion of the welded samples (generally decreasing with increasing welding time or temperature) failed in dual ductile/brittle mode, hence invalidating the EWF test. Even those failing in purely ductile mode showed a measurable interface work of fracture only for the highest weld temperature and time: 188 degrees C and 90 min. Results from the model presented in Part 1 show that this corresponds to the maximum reptated molecular weight reaching close to the peak in the molar mass distribution. Hence this work provides the first experimental evidence that the slow rate of self-diffusion in UHMWPE leads to welded interfaces acting as low-toughness crack paths. Since such interfaces exist around every powder particle in processed UHMWPE this problem cannot be avoided, and it must be accommodated in design of hip and knee bearing surfaces made from this polymer.
NASA Astrophysics Data System (ADS)
Pan, Yi; Lados, Diana A.
2017-04-01
Friction stir welding (FSW) is a solid-state process widely used for joining similar and dissimilar materials for critical applications in the transportation sector. Understanding the effects of the process on microstructure and mechanical properties is critical in design for structural integrity. In this study, four aluminum alloy systems (wrought 6061-T651 and cast A356, 319, and A390) were processed in both as-fabricated and pre-weld heat-treated (T6) conditions using various processing parameters. The effects of processing and heat treatment on the resulting microstructures, macro-/micro-hardness, and tensile properties were systematically investigated and mechanistically correlated to changes in grain size, characteristic phases, and strengthening precipitates. Tensile tests were performed at room temperature both along and across the welding zones. A new method able to evaluate weld quality (using a weld quality index) was developed based on the stress concentration calculated under tensile loading. Optimum processing parameter domains that provide both defect-free welds and good mechanical properties were determined for each alloy and associated with the thermal history of the process. These results were further related to characteristic microstructural features, which can be used for component design and materials/process optimization.
A model for heat and mass input control in GMAW
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smartt, H.B.; Einerson, C.J.
1993-05-01
This work describes derivation of a control model for electrode melting and heat and mass transfer from the electrode to the work piece in gas metal arc welding (GMAW). Specifically, a model is developed which allows electrode speed and welding speed to be calculated for given values of voltage and torch-to-base metal distance, as a function of the desired heat and mass input to the weldment. Heat input is given on a per unit weld length basis, and mass input is given in terms of transverse cross-sectional area added to the weld bead (termed reinforcement). The relationship to prior workmore » is discussed. The model was demonstrated using a computer-controlled welding machine and a proportional-integral (PI) controller receiving input from a digital filter. The difference between model-calculated welding current and measured current is used as controller feedback. The model is calibrated for use with carbon steel welding wire and base plate with Ar-CO[sub 2] shielding gas. Although the system is intended for application during spray transfer of molten metal from the electrode to the weld pool, satisfactory performance is also achieved during globular and streaming transfer. Data are presented showing steady-state and transient performance, as well as resistance to external disturbances.« less
Bottom head to shell junction assembly for a boiling water nuclear reactor
Fife, Alex Blair; Ballas, Gary J.
1998-01-01
A bottom head to shell junction assembly which, in one embodiment, includes an annular forging having an integrally formed pump deck and shroud support is described. In the one embodiment, the annular forging also includes a top, cylindrical shaped end configured to be welded to one end of the pressure vessel cylindrical shell and a bottom, conical shaped end configured to be welded to the disk shaped bottom head. Reactor internal pump nozzles also are integrally formed in the annular forging. The nozzles do not include any internal or external projections. Stubs are formed in each nozzle opening to facilitate welding a pump housing to the forging. Also, an upper portion of each nozzle opening is configured to receive a portion of a diffuser coupled to a pump shaft which extends through the nozzle opening. Diffuser openings are formed in the integral pump deck to provide additional support for the pump impellers. The diffuser opening is sized so that a pump impeller can extend at least partially therethrough. The pump impeller is connected to the pump shaft which extends through the nozzle opening.
Bottom head to shell junction assembly for a boiling water nuclear reactor
Fife, A.B.; Ballas, G.J.
1998-02-24
A bottom head to shell junction assembly which, in one embodiment, includes an annular forging having an integrally formed pump deck and shroud support is described. In the one embodiment, the annular forging also includes a top, cylindrical shaped end configured to be welded to one end of the pressure vessel cylindrical shell and a bottom, conical shaped end configured to be welded to the disk shaped bottom head. Reactor internal pump nozzles also are integrally formed in the annular forging. The nozzles do not include any internal or external projections. Stubs are formed in each nozzle opening to facilitate welding a pump housing to the forging. Also, an upper portion of each nozzle opening is configured to receive a portion of a diffuser coupled to a pump shaft which extends through the nozzle opening. Diffuser openings are formed in the integral pump deck to provide additional support for the pump impellers. The diffuser opening is sized so that a pump impeller can extend at least partially therethrough. The pump impeller is connected to the pump shaft which extends through the nozzle opening. 5 figs.
NASA Astrophysics Data System (ADS)
Rama Subbanna, S.; Suryakalavathi, M., Dr.
2017-08-01
This paper is an attempt to accomplish a performance analysis of the different control techniques on spikes reduction method applied on the medium frequency transformer based DC spot welding system. Spike reduction is an important factor to be considered while spot welding systems are concerned. During normal RSWS operation welding transformer’s magnetic core can become saturated due to the unbalanced resistances of both transformer secondary windings and different characteristics of output rectifier diodes, which causes current spikes and over-current protection switch-off of the entire system. The current control technique is a piecewise linear control technique that is inspired from the DC-DC converter control algorithms to register a novel spike reduction method in the MFDC spot welding applications. Two controllers that were used for the spike reduction portion of the overall applications involve the traditional PI controller and Optimized PI controller. Care is taken such that the current control technique would maintain a reduced spikes in the primary current of the transformer while it reduces the Total Harmonic Distortion. The performance parameter that is involved in the spikes reduction technique is the THD, Percentage of current spike reduction for both techniques. Matlab/SimulinkTM based simulation is carried out for the MFDC RSWS with KW and results are tabulated for the PI and Optimized PI controllers and a tradeoff analysis is carried out.
Immediate Implant Placement in Sockets with Asymptomatic Apical Periodontitis.
Crespi, Roberto; Capparé, Paolo; Crespi, Giovanni; Lo Giudice, Giuseppe; Gastaldi, Giorgio; Gherlone, Enrico
2017-02-01
The purpose of the present study was to evaluate if the presence of granulation tissue in asymptomatic apical periodontitis compromised immediate implant placement. Patients requiring extraction of one tooth (maxillary and mandibular incisive, canine or premolar) with asymptomatic apical periodontitis, were recruited for this prospective study. They were randomly scheduled into two groups: in first group (A) including 30 teeth, reactive soft tissue was debrided before implant placement, and in second group (B) including 30 teeth, reactive soft tissue was left in the apical lesion. Implants were positioned immediately after tooth extraction, and were loaded after 3 months in both groups. Cone beam computed tomography was performed before tooth extraction and at 1-year follow-up to evaluate the radiolucency around the root apex and the implant, bucco-lingual bone levels were also checked. Sixty patients were included in this study. Sixty implants were placed immediately after tooth extraction and, at 1-year follow-up, a survival rate of 100% was reported. After one year both groups showed absence of radiolucent zone at the apical region of implants. All fresh sockets presented a buccal-palatal bone reduction in both groups after one year, even if not statistically significant differences were found between baseline bone levels and within groups. Within the limitations of the present study, the immediate placement of implants into the extraction sockets with asymptomatic apical periodontitis, in presence of primary stability, did not lead to an increased rate of complications and rendered an equally favorable type of tissue integration. © 2016 Wiley Periodicals, Inc.
Flaws detection and localization in weld structure using the topological energy method
NASA Astrophysics Data System (ADS)
Lubeigt, Emma; Mensah, Serge; Rakotonarivo, Sandrine; Chaix, Jean-François; Gobillot, Gilles; Baqué, François
2017-02-01
The non-destructive testing of austenitic welds using ultrasound plays an important role in the assessment of the structural integrity and safety of critical structures in a nuclear reactor. The bedspring and the deck are complex welded structures of very restricted access; the ability to reliably detect and locate defects like cracks is therefore a difficult challenge. Ultrasonic testing is a well-recognized non-invasive technique which exhibits high characterization performances in homogeneous media (steel). However, its capabilities are hampered when operating in heterogeneous and anisotropic austenitic welds because of deviation and splitting of the ultrasonic beam. In order to rise to this important challenge, a model-based method is proposed, which takes into account a prior knowledge corresponding to the welding procedure specifications that condition the austenitic grains orientation within the weld and thus the wave propagation. The topological imaging method implemented is a differential approach which, compares signals from the reference defect-free medium to the inspected medium. It relies on combinations of two computed ultrasonic fields, one forward and one adjoint. Numerical simulations and experiments have been carried out to validate the practical relevance of this approach to detect and locate a flaw in a weld.
Pin Load Control Applied to Retractable Pin Tool Technology and its Characterization
NASA Technical Reports Server (NTRS)
Oelgoetz, Peter A.
2000-01-01
Until the development of retractable pin tool (RPT) technology, friction stir welding (FSW) was limited to constant thickness joining of aluminum materials and the choices of keyhole elimination focused on traditional fusion and plug weld repair techniques. An invention, US Patent Number 5,893,507, "Auto-Adjustable Pin Tool for Friction Stir Welding" assigned to NASA, demonstrated an approach to resolve these serious drawbacks. This approach brings forth a technique that allows the crater, or keyhole, to be closed out automatically at the end of the weld joint without adding any additional equipment or material. Also the probe length can be varied automatically in the weld joint to compensate for material thickness changes, such as, in a tapered joint. This paper reports the effects of pin extension and retraction rates in the weld joint and its correlation to weld quality. The investigation utilized a pin load-detecting device that was integrated in the Phase 2A RPT designed by Boeing for NASA/MSFC. The RPT modification provided pin load data that was accessed and used to eliminate root side indications and determine pin manipulation rates necessary to produce consistence homogeneous joints.
Pin Load Control Applied to Retractable Pin Tool Technology and its Characterization
NASA Technical Reports Server (NTRS)
Oelgoetz, Peter
2000-01-01
Until the development of retractable pin tool (RPT) technology, friction stir welding (FSW) was limited to constant thickness joining of aluminum materials and the choices of keyhole elimination focused on traditional fusion and plug weld repair techniques. An invention, US Patent Number 5,893.507, "Auto-Adjustable Pin Tool for Friction Stir Welding" assigned to NASA, demonstrated an approach to resolve these serious drawbacks. This approach brings forth a technique that allows the crater, or keyhole, to be closed out automatically at the end of the weld joint without adding any additional equipment or material. Also the probe length can be varied automatically in the weld joint to compensate for material thickness changes, such as, in a tapered joint. This paper reports the effects of pin extension and retraction rates in the weld joint and its correlation to weld quality. The investigation utilized a pin load-detecting device that was integrated in the Phase 2A RPT designed by Boeing for NASA/MSFC. The RPT modification provided pin load data that was accessed and used to eliminate root side indications and determine pin manipulation rates necessary to produce consistence homogeneous joints.
Pin Load Control Applied to Retractable Pin Tool Technology and Its Characterization
NASA Technical Reports Server (NTRS)
Olegoetz, P.
1999-01-01
Until the development of retractable pin tool (RPT) technology, friction stir welding (FSW) was limited to constant thickness joining of aluminum materials and the choices of keyhole elimination focused on traditional fusion and plug weld repair techniques. An invention, US Patent Number 5,893,507, "Auto-Adjustable Pin Tool for Friction Stir Welding" assigned to NASA, demonstrated an approach to resolve these serious drawbacks. This approach brings forth a technique that allows the crater, or keyhole, to be closed out automatically at the end of the weld joint without adding any additional equipment or material. Also the probe length can be varied automatically in the weld joint to compensate for material thickness changes, such as, in a tapered joint. This paper reports the effects of pin extension and retraction rates in the weld joint and its correlation to weld quality. The investigation utilized a pin load-detecting device that was integrated in the Phase IIA RPT designed by Boeing for NASA/MSFC. The RPT modification provided pin load data that was accessed and used to eliminate root side indications and determine pin manipulation rates necessary to produce consistence homogeneous joints.
Al-Fakih, Ebrahim; Arifin, Nooranida; Pirouzi, Gholamhossein; Mahamd Adikan, Faisal Rafiq; Shasmin, Hanie Nadia; Abu Osman, Noor Azuan
2017-08-01
This paper presents a fiber Bragg grating (FBG)-instrumented prosthetic silicone liner that provides cushioning for the residual limb and can successfully measure interface pressures inside prosthetic sockets of lower-limb amputees in a simple and practical means of sensing. The liner is made of two silicone layers between which 12 FBG sensors were embedded at locations of clinical interest. The sensors were then calibrated using a custom calibration platform that mimics a real-life situation. Afterward, a custom gait simulating machine was built to test the liner performance during an amputee's simulated gait. To validate the findings, the results were compared to those obtained by the commonly used F-socket mats. As the statistical findings reveal, both pressure mapping methods measured the interface pressure in a consistent way, with no significant difference (P-values ≥0.05). This pressure mapping technique in the form of a prosthetic liner will allow prosthetics professionals to quickly and accurately create an overall picture of the interface pressure distribution inside sockets in research and clinical settings, thereby improving the socket fit and amputee's satisfaction. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).
Congenital anophthalmia: current concepts in management.
Quaranta-Leoni, Francesco M
2011-09-01
The introduction of hydrogel socket and orbital expanders has modified the approach towards the rehabilitation of congenital anophthalmia. This study highlights the most recent advances for the treatment of congenital anophthalmia based on personal experience and the review of recent literature. Hydrogel socket expanders may be positioned as an out-patient procedure with topical anaesthesia, using cyanoacrylate glue as opposed to temporary tarsorraphy. Increased orbital volume has been confirmed by computed tomography (CT) scan or magnetic resonance imaging (MRI) following early dermis-fat graft in children with congenital anophthalmia. An orbital tissue expander made of an inflatable silicone globe sliding on a titanium T-plate and secured to the lateral orbital rim appears to be effective to stimulate orbital bone growth and development. Congenital anophthalmia has a complex cause with both genetic and environmental factors involved. The ideal treatment is simultaneous expansion of the eyelids, socket and orbital bones, and it should begin after birth as soon as possible. Socket expansion with self-inflating expanders is a useful technique, although custom-made conformers may produce similar results. Dermis-fat grafts are another reasonable option as an orbital implant, following adequate lid and socket expansion.
Conjunctival Blue Naevus in an Anophthalmic Socket.
Quhill, Hibba; Rundle, Paul A; Mudhar, Hardeep Singh
2017-09-01
To describe an unusual brown pigmented lesion of the conjunctiva in an anophthalmic socket in a 16-year-old male. A 16-year-old male patient presented with socket irritation whilst wearing an artificial eye due to meibomian gland dysfunction. An area of flat, subepithelial, dark brown pigmentation with irregular and indistinct borders on the bulbar conjunctiva of the anophthalmic socket was seen. The patient believed it had been present for at least 2 years. His past ocular history was of childhood trauma to the right eye at the age of 9 years, and he underwent primary enucleation and hydroxyapatite orbital implant insertion at that time. Unfortunately, the implant extruded and was removed a year later. An incisional biopsy of the pigmented lesion showed a conjunctival, subepithelial bland spindle cell melanocytic lesion, with uniform-sized and -shaped melanosomes. Immunohistochemistry showed the cells to express Melan A and HMB45 and they were negative for CD68 and pan-cytokeratins. The features were of a common blue naevus. This is the first documentation of a post-enucleation conjunctival naevus in an anophthalmic socket. We propose a pathogenesis and suggest surveillance as there is a risk of transformation to melanoma.
Central fabrication: Carved positive assessment
Sanders, Joan E; Severance, Michael R; Myers, Timothy R; Ciol, Marcia A
2015-01-01
In this research we investigated the degree of error during the carving phase of central fabrication of prosthetic sockets for people with limb amputation. Three different model shapes were ordered from each of ten central fabrication companies. Using an accurate custom mechanical digitizer and alignment algorithm, we digitized the models and then compared the model shapes with the electronic file shapes. Results showed that 24 of the 30 models had volumes larger than the electronic file shapes while 24 had volumes that were smaller. 29 of the 30 models were oversized at the proximal aspect of the tibial tuberosity and undersized at the patellar tendon and popliteal areas. This error would result in a socket that had less tibial tubercle relief than intended in addition to a larger anterior-posterior dimension than desired. Comparison of the model shapes with socket shapes assessed for nine of the companies in a previous study showed that for five of the companies the sockets were relatively undersized over the tibial crest and fibular head. The results indicate that the socket the prosthetist receives will not always fit as planned, and that errors in the carving process are a source of the discrepancies. PMID:21515893
Arruda, Thiago; Sukekava, Flávia; de Souza, André B; Rasmusson, Lars; Araújo, Maurício G
2013-07-01
The aim of the present study was to evaluate the effect of the placement of titanium granules in fresh extraction sockets on early bone formation. The mesial roots of the third maxillary premolars of five adult beagle dogs were removed. On one side of the maxilla (Test group) the fresh extraction socket was grafted with titanium granules, while the contra-lateral socket was left non-grafted (Control group). After 1 month of healing, the dogs were euthanized and biopsies were obtained. The healing tissues were described, and histometric measurements were performed to obtain the percentage area occupied by connective tissue, new mineralized bone, bone marrow, and biomaterial particles. After 1 month of healing the findings from the histological examination revealed the titanium graft to be well incorporated into the provisional connective tissue or newly formed woven bone. The histometric measurements showed, however, that less mineralized bone was formed in the Test group than in the Control group. The present study suggests that the use of titanium granules in fresh extraction sockets was conducive to new bone formation. The graft of titanium granules seems, however, to delay the early phase of the healing process. Copyright © 2012 Wiley Periodicals, Inc.
Hip Resurfacing: An Alternative to Conventional Hip Replacement?
... and capped with a metal prosthesis. The hip socket is fitted with a metal cup. As these ... problem, but higher levels may be problematic. The socket prosthesis for a traditional hip replacement is usually ...
33 CFR 154.106 - Incorporation by reference.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 20, Switzerland. (1) IEC 60309-1 Plugs, Socket-Outlets and Couplers for Industrial Purposes—Part 1: General Requirements, Edition 4.2 2012-06, IBR approved for § 154.2102(b). (2) IEC 60309-2 Plugs, Socket...
40. DETAIL OF BRIDGE NO. 9 ROCKER BEARING AND SOCKET, ...
40. DETAIL OF BRIDGE NO. 9 ROCKER BEARING AND SOCKET, SEPARATED. LOOKING NORTH. - Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, Upper New York Bay, Jersey City, Hudson County, NJ
19. CUSHMAN DAM SPILLWAY FLASHBOARD SOCKETS. March 1927 Reference ...
19. CUSHMAN DAM SPILLWAY - FLASHBOARD SOCKETS. March 1927 Reference No. BA-056 - Cushman No. 1 Hydroelectric Power Plant, Spillway, North Fork of Skokomish River, 5 miles West of Hood Canal, Hoodsport, Mason County, WA
... of metal and the socket is made of plastic (polyethylene) or has a plastic lining. Ceramic-on-Polyethylene: The ball is made of ceramic and the socket is made of plastic (polyethylene) or has a plastic lining. Metal-on- ...
NASA Astrophysics Data System (ADS)
Larsson, Johnny K.
The Volvo XC60 car body contains numerous parts in Ultra High Strength Steels (UHSS) in order to guarantee the structural integrity of the car in the event of a crash situation. Most of the parts are manufactured in a hot-forming process, so called presshardening, resulting in component tensile strength in the range of 1,500 MPa. As this type of material also presents fairly high carbon content (˜0.22%) it brings a challenge when it comes to welding. The Volvo XC60 car body is at the same time to a large extent assembled by laser welding technology. In early development stages of the project (Y413), it was observed that laser welding of hot-formed components presented a number of challenges due to the unique conditions offered by this welding method. The presentation will thoroughly describe the modes of procedure how to avoid crack inducement during the welding operation. A variable analysis approach was used based on the present circumstances at the production facility in the Gent plant. Crucial variables at laser welding such as gap between sheets, focal point position, welding speed and laser weld position relative to the flange edge were included in a test matrix and welding trials were carried out accordingly in the Pilot Plant in Gothenburg. The paper will discuss those welding results, the subsequent analysis and plausible theoretic explanations. From the lessons learnt in this research, the optimum laser welding parameters were then transferred to the laser welding stations in the Gent plant. There it has been proven, that also at high volume automotive manufacturing, it is possible to provide an outstanding weld quality also at such difficult pre-conditions. The presentation ends with some facts and figures and experiences from high volume series production, which also includes aspects on quality assurance.
241-AP Tank Farm Construction Extent of Condition Review for Tank Integrity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barnes, Travis J.; Gunter, Jason R.; Reeploeg, Gretchen E.
2014-04-04
This report provides the results of an extent of condition construction history review for the 241-AP tank farm. The construction history of the 241-AP tank farm has been reviewed to identify issues similar to those experienced during tank AY-102 construction. Those issues and others impacting integrity are discussed based on information found in available construction records, using tank AY-102 as the comparison benchmark. In the 241-AP tank farm, the sixth double-shell tank farm constructed, tank bottom flatness, refractory material quality, post-weld stress relieving, and primary tank bottom weld rejection were improved.
Last, G.A.
1960-07-19
A process is given for enclosing the uranium core of a nuclear fuel element by placing the core in an aluminum cup and closing the open end of the cup over the core. As the metal of the cup is brought together in a weld over the center of the end of the core, it is extruded inwardly as internal projection into a central recess in the core and outwardly as an external projection. Thus oxide inclusions in the weld of the cup are spread out into the internal and external projections and do not interfere with the integrity of the weld.
Taberner-Vallverdú, Maria; Sánchez-Garcés, Mª Ángeles
2017-01-01
Background Dry socket is one of the most common complications that develops after the extraction of a permanent tooth, and its prevention is more effective than its treatment. Objectives Analyze the efficacy of different methods used in preventing dry socket in order to decrease its incidence after tooth extraction. Material and Methods A Cochrane and PubMed-MEDLINE database search was conducted with the search terms “dry socket”, “prevention”, “risk factors”, “alveolar osteitis” and “fibrynolitic alveolitis”, both individually and using the Boolean operator “AND”. The inclusion criteria were: clinical studies including at least 30 patients, articles published from 2005 to 2015 and written in English. The exclusion criteria were case reports and nonhuman studies. Results 30 publications were selected from a total of 250. Six of the 30 were excluded after reading the full text. The final review included 24 articles: 9 prospective studies, 2 retrospective studies and 13 clinical trials. They were stratified according to their level of scientific evidence using SIGN criteria (Scottish Intercollegiate Guidelines Network). Conclusions All treatments included in the review were aimed at decreasing the incidence of dry socket. Locally administering chlorhexidine or applying platelet-rich plasma reduces the likelihood of developing this complication. Antibiotic prescription does not avoid postoperative complications after lower third molar surgery. With regard to risk factors, all of the articles selected suggest that patient age, history of previous infection and the difficulty of the extraction are the most common predisposing factors for developing dry socket. There is no consensus that smoking, gender or menstrual cycles are risk factors. Taking the scientific quality of the articles evaluated into account, a level B recommendation has been given for the proposed-procedures in the prevention of dry socket. Key words:Dry socket, prevention, alveolar osteitis, risk factors. PMID:29053647
Changes in PGE2 signaling after submandibulectomy alter post-tooth extraction socket healing.
Mohn, Claudia Ester; Troncoso, Gastón Rodolfo; Bozzini, Clarisa; Conti, María Inés; Fernandez Solari, Javier; Elverdin, Juan Carlos
2018-03-10
Saliva is very important to oral health, and a salivary deficit has been shown to bring serious problems to oral health. There is scant information about the mechanisms through which salivary glands participate in post-tooth extraction socket healing. Therefore, the aim of the present study was to investigate the effect of submandibulectomy (SMx), consisting of the ablation of submandibular and sublingual glands (SMG and SLG, respectively), on PGE 2 signaling and other bone regulatory molecules, such as OPG and RANKL, involved in tooth extraction socket healing. Male Wistar rats, 70 g body weight, were assigned to an experimental (subjected to SMx) or a control group (sham operated). One week later, the animals in both groups underwent bilateral extraction of the first mandibular molars. The effect of SMx on different stages of socket healing after tooth extraction (7, 14, and 30 days) was studied by evaluating some parameters of inflammation, including PGE 2 and its receptors, and of bone metabolism, as well as by performing bone biomechanical studies. SMx increased TNFα and PGE 2 content as well as cyclooxygenase-II (COX-II) expression in tooth socket tissue at almost all the studied time points. SMx also had an effect on mRNA expression of PGE 2 receptors at the different time points, but did not significantly alter osteoprotegerin (OPG) and RANKL mRNA expression at any of the studied time points. In addition, an increase in bone mass density was observed in SMx rats compared with matched controls, and the structural and mechanical bone properties of the mandibular socket bone were also affected by SMx. Our results suggest that the SMG/SLG complex regulates cellular activation and differentiation by modulating the production of molecules intervening in tooth extraction socket repair, including the PGE 2 signaling system, which would therefore account for the higher density and resistance of the newly formed bone in SMx rat. © 2018 by the Wound Healing Society.
Efficacy of different methods used for dry socket management: A systematic review.
Taberner-Vallverdú, Maria; Nazir, Mariam; Sánchez-Garcés, M Ángeles; Gay-Escoda, Cosme
2015-09-01
Dry socket is one of the most common complications occurring after the extraction of a permanent tooth, but in spite of its high incidence there is not an established treatment for this condition. Analyze the efficacy of different methods used in the management of dry socket regarding results of pain's relief and alveolar mucosa healing compared to conventional surgical treatment of curettage and saline irrigation. A Cochrane and PubMed-MEDLINE database search was conducted with the search terms "dry socket", "post-extraction complications", "alvogyl", "alveolar osteitis" and "fibrynolitic alveolitis", individually and next, using the Boolean operator "AND". The inclusion criteria were: clinical studies including at least 10 patients, articles published from 2004 to 2014 written in English. The exclusion criteria were case reports and nonhuman studies. 11 publications were selected from a total of 627. Three of the 11 were excluded after reading the full text. The final review included 8 articles: 3 prospective studies, 2 retrospective studies and 3 clinical trials. They were stratified according to their level of scientific evidence using the SORT criteria (Strenght of Recommendation Taxonomy). All treatments included in the review have the aim to relief patient's pain and promote alveolar mucosa healing in dry socket. Given the heterogeneity of interventions and the type of measurement scale, the results are difficult to compare. Curettage and irrigation should be carried out in dry socket, as well as another therapy such as LLLT, zinc oxide eugenol or plasma rich in growth factors, which are the ones that show better results in pain remission and alveolar mucosa healing. Assessment alveolar bone esposure must be a factor to consider in future research. Taking into account the scientific quality of the articles evaluated, a level B recommendation is given for therapeutic interventions proposed for the treatment of dry socket.
Cardaropoli, Daniele; Tamagnone, Lorenzo; Roffredo, Alessandro; Gaveglio, Lorena; Cardaropoli, Giuseppe
2012-08-01
After tooth extraction, varying amounts of bone resorption occur because of qualitative and quantitative changes at the edentulous site of the alveolar process. The aims of this randomized controlled clinical trial were (1) to compare the postextraction changes in residual ridge dimensions during spontaneous healing with those during socket preservation, (2) to analyze the histologic and histomorphometric aspects of the grafted sockets, and (3) to compare probing procket depth (PPD) and clinical attachment level (CAL) changes at teeth adjacent to extraction sites. Forty-eight teeth were extracted from 41 patients referred for extraction of 1 or more maxillary or mandibular premolars or molars. The edentulous sites were randomly assigned to the control (EXT, extraction alone) or experimental groups (SP, extraction and socket preservation). In the SP group, the sockets were filled with bovine bone mineral and covered with porcine collagen membrane. At baseline and after 4 months, PPD, gingival recession (REC), and CAL were measured at teeth adjacent to the edentulous sites. The changes in ridge dimensions from baseline to 4 months were assessed on dental casts. At 4 months, bone was harvested from the grafted areas in the SP group and the edentulous areas in the EXT group. PPD, REC, and CAL were comparable between groups. However, from baseline to 4 months, the SP group showed significantly less reduction in ridge width (1.04 ± 1.08 mm vs 4.48 ± 0.65 mm, P < .001) and height (0.46 ± 0.46 mm vs 1.54 ± 0.33 mm, P < .001). Histologically, the grafted sockets exhibited various stages of bone maturation and formation without inflammatory responses. No significant difference in the mineralized and nonmineralized fractions was noted between the groups. Socket preservation using bovine bone mineral and porcine collagen membrane considerably limits the amount of horizontal and vertical bone resorption when compared with extraction alone.
Using software security analysis to verify the secure socket layer (SSL) protocol
NASA Technical Reports Server (NTRS)
Powell, John D.
2004-01-01
nal Aeronautics and Space Administration (NASA) have tens of thousands of networked computer systems and applications. Software Security vulnerabilities present risks such as lost or corrupted data, information the3, and unavailability of critical systems. These risks represent potentially enormous costs to NASA. The NASA Code Q research initiative 'Reducing Software Security Risk (RSSR) Trough an Integrated Approach '' offers, among its capabilities, formal verification of software security properties, through the use of model based verification (MBV) to address software security risks. [1,2,3,4,5,6] MBV is a formal approach to software assurance that combines analysis of software, via abstract models, with technology, such as model checkers, that provide automation of the mechanical portions of the analysis process. This paper will discuss: The need for formal analysis to assure software systems with respect to software and why testing alone cannot provide it. The means by which MBV with a Flexible Modeling Framework (FMF) accomplishes the necessary analysis task. An example of FMF style MBV in the verification of properties over the Secure Socket Layer (SSL) communication protocol as a demonstration.
DOT National Transportation Integrated Search
2014-02-01
To ensure that Florida bridges remain safe and structurally secure for their 50-year-plus service life, they are inspected regularly. For steel bridges, welds critical to the bridges integrity do not even leave the workshop unless they meet rigoro...
Thermal regulation in multiple-source arc welding involving material transformations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doumanidis, C.C.
1995-06-01
This article addresses regulation of the thermal field generated during arc welding, as the cause of solidification, heat-affected zone and cooling rate related metallurgical transformations affecting the final microstructure and mechanical properties of various welded materials. This temperature field is described by a dynamic real-time process model, consisting of an analytical composite conduction expression for the solid region, and a lumped-state, double-stream circulation model in the weld pool, integrated with a Gaussian heat input and calibrated experimentally through butt joint GMAW tests on plain steel plates. This model serves as the basis of an in-process thermal control system employing feedbackmore » of part surface temperatures measured by infrared pyrometry; and real-time identification of the model parameters with a multivariable adaptive control strategy. Multiple heat inputs and continuous power distributions are implemented by a single time-multiplexed torch, scanning the weld surface to ensure independent, decoupled control of several thermal characteristics. Their regulation is experimentally obtained in longitudinal GTAW of stainless steel pipes, despite the presence of several geometrical, thermal and process condition disturbances of arc welding.« less
Polymethylmethacrylate (PMMA) Material Test Results for the Capillary Flow Experiments (CFE)
NASA Technical Reports Server (NTRS)
Lerch, Bradley A.; Thesken, John C.; Bunnell, Charles T.
2007-01-01
In support of the Capillary Flow Experiments (CFE) program, several polymethylmethacrylate (PMMA) flight vessels were constructed. Some vessels used a multipiece design, which was chemically welded together. Due to questions regarding the effects of the experiment fluid (silicone oil) on the weld integrity, a series of tests were conducted to provide evidence of the adequacy of the current vessel design. Tensile tests were conducted on PMMA samples that were both in the as-received condition, and also aged in air or oil for up to 8 weeks. Both welded and unwelded samples were examined. Fracture of the joints was studied using notched tensile specimens and Brazilian disk tests. Results showed that aging had no effect on tensile properties. While the welded samples were weaker than the base parent material, the weld strength was found to be further degraded by bubbles in the weld zone. Finally a fracture analysis using the worst-case fracture conditions of the vessel was performed, and the vessel design was found to have a factor of three safety margin.
Design of rock socketed drilled shafts
DOT National Transportation Integrated Search
1998-09-01
Three field load tests of drilled shafts socketed in Burlington limestone were conducted using the Osterberg load cell. The objective of these tests was to compare the shaft capacities obtained from the field load tests with capacities predicted usin...
21 CFR 872.3680 - Polytetrafluoroethylene (PTFE) vitreous carbon materials.
Code of Federal Regulations, 2010 CFR
2010-04-01
... the sockets in which teeth are rooted) or intended to coat metal surgical implants to be placed in the alveoli (sockets in which the teeth are rooted) or the temporomandibular joints (the joint between the...
21 CFR 872.3680 - Polytetrafluoroethylene (PTFE) vitreous carbon materials.
Code of Federal Regulations, 2013 CFR
2013-04-01
... the sockets in which teeth are rooted) or intended to coat metal surgical implants to be placed in the alveoli (sockets in which the teeth are rooted) or the temporomandibular joints (the joint between the...
21 CFR 872.3680 - Polytetrafluoroethylene (PTFE) vitreous carbon materials.
Code of Federal Regulations, 2014 CFR
2014-04-01
... the sockets in which teeth are rooted) or intended to coat metal surgical implants to be placed in the alveoli (sockets in which the teeth are rooted) or the temporomandibular joints (the joint between the...