Development opportunities for hospital clinical laboratory joint ventures.

PubMed

Van Riper, J A

1995-01-01

Regional health-care providers are being given the opportunity to collaborate in specialty health-care services. Collaboration to achieve superior economies of scale is very effective in the clinical laboratory industry. National laboratory chains are consolidating and enhancing their control of the industry to ensure their historic profitability. National companies have closed many laboratory facilities and have laid off substantial numbers of laboratory personnel. Health-care providers can regain control of their locally generated laboratory health-care dollars by joining forces with clinical laboratory joint ventures. Laboratorians can assist the healthcare providers in bringing laboratory services and employment back to the local community. New capital for operational development and laboratory information systems will help bring the laboratory to the point of care. The independent regional laboratory is focused on supporting the medical needs of the community. The profit generated from a laboratory joint venture is shared among local health-care providers, supporting their economic viability. The laboratories' ability to contribute to the development of profit-making ventures will provide capital for new laboratory development. All of the above will ensure the clinical laboratories' role in providing quality health care to our communities and employment opportunities for laboratory personnel.

Development of Bonded Joint Technology for a Rigidizable-Inflatable Deployable Truss

NASA Technical Reports Server (NTRS)

Smeltzer, Stanley S., III

2006-01-01

Microwave and Synthetic Aperture Radar antenna systems have been developed as instrument systems using truss structures as their primary support and deployment mechanism for over a decade. NASA Langley Research Center has been investigating fabrication, modular assembly, and deployment methods of lightweight rigidizable/inflatable linear truss structures during that time for large spacecraft systems. The primary goal of the research at Langley Research Center is to advance these existing state-of-the-art joining and deployment concepts to achieve prototype system performance in a relevant space environment. During 2005, the development, fabrication, and testing of a 6.7 meter multi-bay, deployable linear truss was conducted at Langley Research Center to demonstrate functional and precision metrics of a rigidizable/inflatable truss structure. The present paper is intended to summarize aspects of bonded joint technology developed for the 6.7 meter deployable linear truss structure while providing a brief overview of the entire truss fabrication, assembly, and deployment methodology. A description of the basic joint design, surface preparation investigations, and experimental joint testing of component joint test articles will be described. Specifically, the performance of two room temperature adhesives were investigated to obtain qualitative data related to tube folding testing and quantitative data related to tensile shear strength testing. It was determined from the testing that a polyurethane-based adhesive best met the rigidizable/inflatable truss project requirements.

Dynamic Cytology and Transcriptional Regulation of Rice Lamina Joint Development1[OPEN

PubMed Central

2017-01-01

Rice (Oryza sativa) leaf angle is determined by lamina joint and is an important agricultural trait determining leaf erectness and, hence, the photosynthesis efficiency and grain yield. Genetic studies reveal a complex regulatory network of lamina joint development; however, the morphological changes, cytological transitions, and underlying transcriptional programming remain to be elucidated. A systemic morphological and cytological study reveals a dynamic developmental process and suggests a common but distinct regulation of the lamina joint. Successive and sequential cell division and expansion, cell wall thickening, and programmed cell death at the adaxial or abaxial sides form the cytological basis of the lamina joint, and the increased leaf angle results from the asymmetric cell proliferation and elongation. Analysis of the gene expression profiles at four distinct developmental stages ranging from initiation to senescence showed that genes related to cell division and growth, hormone synthesis and signaling, transcription (transcription factors), and protein phosphorylation (protein kinases) exhibit distinct spatiotemporal patterns during lamina joint development. Phytohormones play crucial roles by promoting cell differentiation and growth at early stages or regulating the maturation and senescence at later stages, which is consistent with the quantitative analysis of hormones at different stages. Further comparison with the gene expression profile of leaf inclination1, a mutant with decreased auxin and increased leaf angle, indicates the coordinated effects of hormones in regulating lamina joint. These results reveal a dynamic cytology of rice lamina joint that is fine-regulated by multiple factors, providing informative clues for illustrating the regulatory mechanisms of leaf angle and plant architecture. PMID:28500269

Development of a Lubricant Therapy to Prevent Development of Osteoarthritis after Acute Injury of Synovial Joints

DTIC Science & Technology

2016-10-01

test whether the pathological accumulation of a specific substance found in joint fluid following an injury mediated altered synovial fluid...joint injury contributes to the development of post-traumatic OA and is due, in part, to the pathological accumulation of a...studies, SF samples will be analyzed for the suspected pathological substance as well as lubrication function. 3.b.ii. Aim 2b

Effects of imbalanced muscle loading on hip joint development and maturation.

PubMed

Ford, Caleb A; Nowlan, Niamh C; Thomopoulos, Stavros; Killian, Megan L

2017-05-01

The mechanical loading environment influences the development and maturation of joints. In this study, the influence of imbalanced muscular loading on joint development was studied using localized chemical denervation of hip stabilizing muscle groups in neonatal mice. It was hypothesized that imbalanced muscle loading, targeting either gluteal muscles or quadriceps muscles, would lead to bilateral hip joint asymmetry, as measured by acetabular coverage, femoral head volume and bone morphometry, and femoral-acetabular shape. The contralateral hip joints as well as age-matched, uninjected mice were used as controls. Altered bone development was analyzed using micro-computed tomography, histology, and image registration techniques at postnatal days (P) 28, 56, and 120. This study found that unilateral muscle unloading led to reduced acetabular coverage of the femoral head, lower total volume, lower bone volume ratio, and lower mineral density, at all three time points. Histologically, the femoral head was smaller in unloaded hips, with thinner triradiate cartilage at P28 and thinner cortical bone at P120 compared to contralateral hips. Morphological shape changes were evident in unloaded hips at P56. Unloaded hips had lower trabecular thickness and increased trabecular spacing of the femoral head compared to contralateral hips. The present study suggests that decreased muscle loading of the hip leads to altered bone and joint shape and growth during postnatal maturation. Statement of Clinical Significance: Adaptations from altered muscle loading during postnatal growth investigated in this study have implications on developmental hip disorders that result from asymmetric loading, such as patients with limb-length inequality or dysplasia. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1128-1136, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Development and evaluation of a musculoskeletal model of the elbow joint complex

NASA Technical Reports Server (NTRS)

Gonzalez, Roger V.; Hutchins, E. L.; Barr, Ronald E.; Abraham, Lawrence D.

1993-01-01

This paper describes the development and evaluation of a musculoskeletal model that represents human elbow flexion-extension and forearm pronation-supination. The length, velocity, and moment arm for each of the eight musculotendon actuators were based on skeletal anatomy and position. Musculotendon parameters were determined for each actuator and verified by comparing analytical torque-angle curves with experimental joint torque data. The parameters and skeletal geometry were also utilized in the musculoskeletal model for the analysis of ballistic elbow joint complex movements. The key objective was to develop a computational model, guided by parameterized optimal control, to investigate the relationship among patterns of muscle excitation, individual muscle forces, and movement kinematics. The model was verified using experimental kinematic, torque, and electromyographic data from volunteer subjects performing ballistic elbow joint complex movements.

BMPRIA Mediated Signaling Is Essential for Temporomandibular Joint Development in Mice

PubMed Central

Liu, Chao; Yang, Ling; Sun, Cheng; Ye, Wenduo; Li, Xihai; Chen, Jianquan; Long, Fanxin; Chen, YiPing

2014-01-01

The central importance of BMP signaling in the development and homeostasis of synovial joint of appendicular skeleton has been well documented, but its role in the development of temporomandibular joint (TMJ), also classified as a synovial joint, remains completely unknown. In this study, we investigated the function of BMPRIA mediated signaling in TMJ development in mice by transgenic loss-of- and gain-of-function approaches. We found that BMPRIA is expressed in the cranial neural crest (CNC)-derived developing condyle and glenoid fossa, major components of TMJ, as well as the interzone mesenchymal cells. Wnt1-Cre mediated tissue specific inactivation of BmprIa in CNC lineage led to defective TMJ development, including failure of articular disc separation from a hypoplastic condyle, persistence of interzone cells, and failed formation of a functional fibrocartilage layer on the articular surface of the glenoid fossa and condyle, which could be at least partially attributed to the down-regulation of Ihh in the developing condyle and inhibition of apoptosis in the interzone. On the other hand, augmented BMPRIA signaling by Wnt1-Cre driven expression of a constitutively active form of BmprIa (caBmprIa) inhibited osteogenesis of the glenoid fossa and converted the condylar primordium from secondary cartilage to primary cartilage associated with ectopic activation of Smad-dependent pathway but inhibition of JNK pathway, leading to TMJ agenesis. Our results present unambiguous evidence for an essential role of finely tuned BMPRIA mediated signaling in TMJ development. PMID:25093411

Flat H Redundant Frangible Joint Development

NASA Technical Reports Server (NTRS)

Brown, Chris

2016-01-01

Orion and Commercial Crew Program (CCP) Partners have chosen to use frangible joints for certain separation events. The joints currently available are zero failure tolerant and will be used in mission safety applications. The goal is to further develop a NASA designed redundant frangible joint that will lower flight risk and increase reliability. FY16 testing revealed a successful design in subscale straight test specimens that gained efficiency and supports Orion load requirements. Approach / Innovation A design constraint is that the redundant joint must fit within the current Orion architecture, without the need for additional vehicle modification. This limitation required a design that changed the orientation of the expanding tube assemblies (XTAs), by rotating them 90deg from the standard joint configuration. The change is not trivial and affects the fracture mechanism and structural load paths. To address these changes, the design incorporates cantilevered arms on the break plate. The shock transmission and expansion of the XTA applies force to these arms and creates a prying motion to push the plate walls outward to the point of structural failure at the notched section. The 2014 test design revealed that parts could slip during functioning wasting valuable energy needed to separate the structure with only a single XTA functioning. Dual XTA functioning fully separated the assembly showing a discrepancy can be backed up with redundancy. Work on other fully redundant systems outside NASA is limited to a few patents that have not been subjected to functionality testing Design changes to prevent unwanted slippage (with ICA funding in 2015) showed success with a single XTA. The main goal for FY 2016 was to send the new Flat H RFJ to WSTF where single XTA test failures occurred back in 2014. The plan was to gain efficiency in this design by separating the Flat H RFJ with thicker ligaments with dimensions baselined in 2014. Other modifications included geometry

Development of biomimetic quadruped walking robot with 2-DOF waist joint

NASA Astrophysics Data System (ADS)

Kim, Kyoung-Ho; Park, Se-Hoon; Lee, Yun-Jung

2005-12-01

This paper presented a novel bio-mimetic quadruped walking robot with 2-DOF (Degree Of Freedom) waist joint, which connects the front and the rear parts of the body. The waist-jointed walking robot can guarantee more stable and more animal-like gait than that of a conventional single-rigid-body walking robot. The developed robot, called ELIRO-II (Eating LIzard RObot version 2), can bend its body from side to side by using 1-DOF passive waist joint while the legs is transferred, thereby increasing the stride and speed of the robot. In addition, ELIRO-II has one more active DOF to bend its body up and down, which increases the mobility in irregular terrain such as slope and stairs. We design the mechanical structure of the robot, which is small and light to have high mobility. This research described characteristics of the 2-DOF waists joint and leg mechanism as well as a hardware and software of the controller of ELIRO-II.

A Longitudinal Analysis of Joint Attention and Language Development in Young Children with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Tek, Saime

2010-01-01

Joint attention (JA), which occurs when two individuals focus on the same object or event, plays a critical role in social and language development. Two major kinds of joint attention have been observed: response to joint attention (RJA), in which children follow the attentional focus of their social partners, and initiation of joint attention…

Developing a multi-joint upper limb exoskeleton robot for diagnosis, therapy, and outcome evaluation in neurorehabilitation.

PubMed

Ren, Yupeng; Kang, Sang Hoon; Park, Hyung-Soon; Wu, Yi-Ning; Zhang, Li-Qun

2013-05-01

Arm impairments in patients post stroke involve the shoulder, elbow and wrist simultaneously. It is not very clear how patients develop spasticity and reduced range of motion (ROM) at the multiple joints and the abnormal couplings among the multiple joints and the multiple degrees-of-freedom (DOF) during passive movement. It is also not clear how they lose independent control of individual joints/DOFs and coordination among the joints/DOFs during voluntary movement. An upper limb exoskeleton robot, the IntelliArm, which can control the shoulder, elbow, and wrist, was developed, aiming to support clinicians and patients with the following integrated capabilities: 1) quantitative, objective, and comprehensive multi-joint neuromechanical pre-evaluation capabilities aiding multi-joint/DOF diagnosis for individual patients; 2) strenuous and safe passive stretching of hypertonic/deformed arm for loosening up muscles/joints based on the robot-aided diagnosis; 3) (assistive/resistive) active reaching training after passive stretching for regaining/improving motor control ability; and 4) quantitative, objective, and comprehensive neuromechanical outcome evaluation at the level of individual joints/DOFs, multiple joints, and whole arm. Feasibility of the integrated capabilities was demonstrated through experiments with stroke survivors and healthy subjects.

Development and validation of a periarticular injection technique of the sacroiliac joint in horses.

PubMed

Engeli, E; Haussler, K K; Erb, H N

2004-05-01

Sacroiliac joint osteoarthritis has been recognised as a significant cause of poor performance in competition and racehorses. Reliable diagnostic tools are currently lacking. The diagnosis has been based typically on exclusion of other possible causes of poor performance, back pain and hindlimb lameness. To develop a safe, reliable and minimally invasive periarticular or intra-articular injection technique of potential use for diagnosis and therapy of sacroiliac joint disease in horses. Twenty-six horses were used to develop and assess a medial approach to the sacroiliac joint with a 15 gauge, 25 cm long spinal needle. In Part I, the cadaveric study, the spinal needle was introduced cranial to the contralateral tuber sacrale and advanced along the medial aspect of the ipsilateral iliac wing until the dorsal surface of the sacrum was encountered. One ml methylene blue (MB) was injected in both sacroiliac joint regions of the sacropelvic specimens. The location of MB-stained tissues relative to the sacroiliac joints was recorded after dissection and disarticulation of the sacroiliac joint. In Part II, the in vivo study, 18 horses were used to validate the in vivo application of the sacroiliac joint injection technique. Horses were restrained in stocks and sedated in preparation for needle placement. One ml MB was injected bilaterally prior to euthanasia. Stained tissues were identified and recorded at necropsy. Successful joint injections were characterised as having MB located intra-articularly or < or = 2 cm periarticularly from the sacroiliac joint margin and localised to the middle or caudal third of the sacroiliac joint. Intra-articular MB was not observed in any specimen. However, MB-stained tissue was identified periarticularly in all injection sites (n = 48). Based on the predetermined success criteria, 96% of the methylene blue depots were located at the middle or caudal third of the sacroiliac joint. Dye-stained tissue was located < or = 2 cm from the

Morphogen-based simulation model of ray growth and joint patterning during fin development and regeneration.

PubMed

Rolland-Lagan, Anne-Gaëlle; Paquette, Mathieu; Tweedle, Valerie; Akimenko, Marie-Andrée

2012-03-01

The fact that some organisms are able to regenerate organs of the correct shape and size following amputation is particularly fascinating, but the mechanism by which this occurs remains poorly understood. The zebrafish (Danio rerio) caudal fin has emerged as a model system for the study of bone development and regeneration. The fin comprises 16 to 18 bony rays, each containing multiple joints along its proximodistal axis that give rise to segments. Experimental observations on fin ray growth, regeneration and joint formation have been described, but no unified theory has yet been put forward to explain how growth and joint patterns are controlled. We present a model for the control of fin ray growth during development and regeneration, integrated with a model for joint pattern formation, which is in agreement with published, as well as new, experimental data. We propose that fin ray growth and joint patterning are coordinated through the interaction of three morphogens. When the model is extended to incorporate multiple rays across the fin, it also accounts for how the caudal fin acquires its shape during development, and regains its correct size and shape following amputation.

Joint Attention Behaviours and Vocabulary Development in Children with Down Syndrome

ERIC Educational Resources Information Center

Zampini, L.; Salvi, A.; D'Odorico, L.

2015-01-01

Background: Because of their difficulties in language development, various studies have focussed on the precursors of linguistic skills in children with Down syndrome. However, data on the predictive role of joint attention on language development in this population are inconsistent. The present study aimed to analyse attention behaviours in a…

Impact extractive fracture of jointed steel plates of a bolted joint

NASA Astrophysics Data System (ADS)

Daimaruya, M.; Fujiki, H.; Ambarita, H.

2012-08-01

This study is concerned with the development of a fracture criterion for the impact fracture of jointed steel plates of a bolted joint used in a car body. For the accurate prediction of crash characteristics of car bodies by computer-aided engineering (CAE), it is also necessary to examine the behavior and fracture of jointed steel plates subjected to impact loads. Although the actual impact fracture of jointed steel plates of a bolted joint used in cars is complicated, for simplifying the problem it might be classified into the shear fracture and the extractive fracture of jointed steel plates. Attention is given to the extractive fracture of jointed steel plates in this study. The extractive behavior and fracture of three kinds of steel plates used for cars are examined in experiments and numerical simulations. The impact extraction test of steel plates jointed by a bolt is performed using the one-bar method, together with the static test. In order to understand the mechanism of extractive fracture process of jointed steel plates, numerical simulations by a FEM code LS-DYNA are also carried out. The obtained results suggest that a stress-based fracture criterion may be developed for the impact extractive fracture of jointed steel plates of a bolted joint used in a car body.

Joint Implications for Contracted Logistics

DTIC Science & Technology

2007-03-30

authority with the host nation country and policy on using UCMJ for contracted personnel. As tailored theater policies are developed and contracting...responsibility, this paper recommends better joint training, leader development and joint enablers for contracting operations. JOINT...U.S. Joint Forces Command (JFCOM) are analyzing Congressional and DOD policy to develop procedures and force structure to support contractor

Supporting the joint warfighter by development, training, and fielding of man-portable UGVs

NASA Astrophysics Data System (ADS)

Ebert, Kenneth A.; Stratton, Benjamin V.

2005-05-01

The Robotic Systems Pool (RSP), sponsored by the Joint Robotics Program (JRP), is an inventory of small robotic systems, payloads, and components intended to expedite the development and integration of technology into effective, supportable, fielded robotic assets. The RSP loans systems to multiple users including the military, first-responders, research organizations, and academia. These users provide feedback in their specific domain, accelerating research and development improvements of robotic systems, which in turn allow the joint warfighter to benefit from such changes more quickly than from traditional acquisition cycles. Over the past year, RSP assets have been used extensively for pre-deployment operator and field training of joint Explosive Ordnance Disposal (EOD) teams, and for the training of Navy Reservist repair technicians. These Reservists are part of the Robotic Systems Combat Support Platoon (RSCSP), attached to Space and Naval Warfare Systems Center, San Diego. The RSCSP maintains and repairs RSP assets and provides deployable technical support for users of robotic systems. Currently, a small team from the RSCSP is deployed at Camp Victory repairing and maintaining man-portable unmanned ground vehicles (UGVs) used by joint EOD teams in Operation Iraqi Freedom. The focus of this paper is to elaborate on the RSP and RSCSP and their role as invaluable resources for spiral development in the robotics community by gaining first-hand technical feedback from the warfighter and other users.

Sacroiliac joint dysfunction as a reason for the development of acetabular retroversion: a new theory.

PubMed

Cibulka, Michael T

2014-05-01

Acetabular retroversion has been recently implicated as an important factor in the development of femoral acetabular impingement and hip osteoarthritis. The proper function of the hip joint requires that the anatomic features of the acetabulum and femoral head complement one another. In acetabular retroversion, the alignment of the acetabulum is altered where it opens in a posterolaterally instead of anterior direction. Changes in acetabular orientation can occur with alterations in pelvic tilt (anterior/posterior), and pelvic rotation (left/right). An overlooked problem that alters pelvic tilt and rotation, often seen by physical therapists, is sacroiliac joint dysfunction. A unique feature that develops in patients with sacroiliac joint dysfunction (SIJD) is asymmetry between the left and right innominate bones that can alter pelvic tilt and rotation. This article puts forth a theory suggesting that acetabular retroversion may be produced by sacroiliac joint dysfunction.

Development of a Lubricant Therapy to Prevent Development of Osteoarthritis after Acute Injury of Synovial Joints

DTIC Science & Technology

2015-10-01

AD______________ AWARD NUMBER: W81XWH-14-1-0562 TITLE: Development of a Lubricant Therapy to Prevent Development of Osteoarthritis after Acute...TITLE AND SUBTITLE 5a. CONTRACT NUMBER Development of a Lubricant Therapy to Prevent Development of Osteoarthritis after Acute Injury of Synovial...early-onset osteoarthritis after traumatic joint injury remains a clinical challenge and may be associated with the poor lubricant quality of the

Intra-articular nerve growth factor regulates development, but not maintenance, of injury-induced facet joint pain & spinal neuronal hypersensitivity.

PubMed

Kras, J V; Kartha, S; Winkelstein, B A

2015-11-01

The objective of the current study is to define whether intra-articular nerve growth factor (NGF), an inflammatory mediator that contributes to osteoarthritic pain, is necessary and sufficient for the development or maintenance of injury-induced facet joint pain and its concomitant spinal neuronal hyperexcitability. Male Holtzman rats underwent painful cervical facet joint distraction (FJD) or sham procedures. Mechanical hyperalgesia was assessed in the forepaws, and NGF expression was quantified in the C6/C7 facet joint. An anti-NGF antibody was administered intra-articularly in additional rats immediately or 1 day following facet distraction or sham procedures to block intra-articular NGF and test its contribution to initiation and/or maintenance of facet joint pain and spinal neuronal hyperexcitability. NGF was injected into the bilateral C6/C7 facet joints in separate rats to determine if NGF alone is sufficient to induce these behavioral and neuronal responses. NGF expression increases in the cervical facet joint in association with behavioral sensitivity after that joint's mechanical injury. Intra-articular application of anti-NGF immediately after a joint distraction prevents the development of both injury-induced pain and hyperexcitability of spinal neurons. Yet, intra-articular anti-NGF applied after pain has developed does not attenuate either behavioral or neuronal hyperexcitability. Intra-articular NGF administered to the facet in naïve rats also induces behavioral hypersensitivity and spinal neuronal hyperexcitability. Findings demonstrate that NGF in the facet joint contributes to the development of injury-induced joint pain. Localized blocking of NGF signaling in the joint may provide potential treatment for joint pain. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Analysis of EDZ Development of Columnar Jointed Rock Mass in the Baihetan Diversion Tunnel

NASA Astrophysics Data System (ADS)

Hao, Xian-Jie; Feng, Xia-Ting; Yang, Cheng-Xiang; Jiang, Quan; Li, Shao-Jun

2016-04-01

Due to the time dependency of the crack propagation, columnar jointed rock masses exhibit marked time-dependent behaviour. In this study, in situ measurements, scanning electron microscope (SEM), back-analysis method and numerical simulations are presented to study the time-dependent development of the excavation damaged zone (EDZ) around underground diversion tunnels in a columnar jointed rock mass. Through in situ measurements of crack propagation and EDZ development, their extent is seen to have increased over time, despite the fact that the advancing face has passed. Similar to creep behaviour, the time-dependent EDZ development curve also consists of three stages: a deceleration stage, a stabilization stage, and an acceleration stage. A corresponding constitutive model of columnar jointed rock mass considering time-dependent behaviour is proposed. The time-dependent degradation coefficient of the roughness coefficient and residual friction angle in the Barton-Bandis strength criterion are taken into account. An intelligent back-analysis method is adopted to obtain the unknown time-dependent degradation coefficients for the proposed constitutive model. The numerical modelling results are in good agreement with the measured EDZ. Not only that, the failure pattern simulated by this time-dependent constitutive model is consistent with that observed in the scanning electron microscope (SEM) and in situ observation, indicating that this model could accurately simulate the failure pattern and time-dependent EDZ development of columnar joints. Moreover, the effects of the support system provided and the in situ stress on the time-dependent coefficients are studied. Finally, the long-term stability analysis of diversion tunnels excavated in columnar jointed rock masses is performed.

Development of Thermal Barriers For Solid Rocket Motor Nozzle Joints

NASA Technical Reports Server (NTRS)

Steinetz, Bruce M.; Dunlap, Patrick H., Jr.

2000-01-01

Joints in the Space Shuttle solid rocket motors are sealed by O-rings to contain combustion gases inside the rocket that reach pressures of up to 900 psi and temperatures of up to 5500 F. To provide protection for the O-rings, the motors are insulated with either phenolic or rubber insulation. Gaps in the joints leading up to the O-rings are filled with polysulfide joint-fill compounds as an additional level of protection. The current RSRM nozzle-to-case joint design incorporating primary, secondary, and wiper O-rings experiences gas paths through the joint-fill compound to the innermost wiper O-ring in about one out of every seven motors. Although this does not pose a safety hazard to the motor, it is an undesirable condition that NASA and rocket manufacturer Thiokol want to eliminate. Each nozzle-to-case joint gas path results in extensive reviews and evaluation before flights can be resumed. Thiokol and NASA Marshall are currently working to improve the nozzle-to-case joint design by implementing a more reliable J-leg design that has been used successfully in the field and igniter joint. They are also planning to incorporate the NASA Glenn braided carbon fiber thermal barrier into the joint. The thermal barrier would act as an additional level of protection for the O-rings and allow the elimination of the joint-fill compound from the joint.

[Development of polyaxial locking plate screw system of sacroiliac joint].

PubMed

Fan, Weijie; Xie, Xuesong; Zhou, Shuping; Zhang, Yonghu

2014-09-01

To develop an instrument for sacroiliac joint fixation with less injury and less complications. Firstly, 18 adult pelvic specimens (8 males and 10 females) were used to measure the anatomical data related to the locking plates and locking screws on the sacrum and ilium, and the polyaxial locking plate screw system of the sacroiliac joint was designed according to the anatomic data. This system was made of medical titanium alloy. Then 4 adult male plevic specimens were harvested and the experiment was divided into 3 groups: group A (normal pelvic), group B (the dislocated sacroiliac joint fixed with sacroiliac screws), and group C (the dislocated sacroiliac joint fixed with polyaxial locking plate screw system). The vertical displacement of sacroiliac joint under the condition of 0-700 N vertical load and the horizontal displacement on angle under the condition of 0-12 N·m torsional load were compared among the 3 groups by using the biological material test system. Finally, the simulated application test was performed on 1 adult male cadaveric specimen to observe soft tissue injury and the position of the locking plate and screw by X-ray films. According to the anatomic data of the sacrum and ilium, the polyaxial locking plate screw system of the sacroiliac joint was designed. The biomechanical results showed that the vertical displacement of the sacroiliac joint under the condition of 0-700 N vertical load in group A was significantly bigger than that in group B and group C (P < 0.05), but there was no significant difference between group B and group C (P > 0.05). The horizontal displacement on angle under the condition of 0-12 N·m torsional load in group A was significantly less than that in group B and group C (P < 0.05). The horizontal displacement on angle under the condition of 0-6 N·m torsional load in group B was bigger than that in group C, and the horizontal displacement on angle under the condition of 6-12 N·m torsional load in group B was less than

Thermal Barriers Developed for Solid Rocket Motor Nozzle Joints

NASA Technical Reports Server (NTRS)

Steinetz, Bruce M.; Dunlap, Patrick H., Jr.

2000-01-01

Space shuttle solid rocket motor case assembly joints are sealed with conventional O-ring seals that are shielded from 5500 F combustion gases by thick layers of insulation and by special joint-fill compounds that fill assembly splitlines in the insulation. On a number of occasions, NASA has observed hot gas penetration through defects in the joint-fill compound of several of the rocket nozzle assembly joints. In the current nozzle-to-case joint, NASA has observed penetration of hot combustion gases through the joint-fill compound to the inboard wiper O-ring in one out of seven motors. Although this condition does not threaten motor safety, evidence of hot gas penetration to the wiper O-ring results in extensive reviews before resuming flight. The solid rocket motor manufacturer (Thiokol) approached the NASA Glenn Research Center at Lewis Field about the possibility of applying Glenn's braided fiber preform seal as a thermal barrier to protect the O-ring seals. Glenn and Thiokol are working to improve the nozzle-to-case joint design by implementing a more reliable J-leg design and by using a braided carbon fiber thermal barrier that would resist any hot gases that the J-leg does not block.

Design and technical support for development of a molded fabric space suit joint

NASA Technical Reports Server (NTRS)

Olson, L. Howard

1994-01-01

NASA Ames Research Center has under design a new joint or element for use in a space suit. The design concept involves molding a fabric to a geometry developed at Ames. Unusual characteristics of this design include the need to produce a fabric molding draw ratio on the order of thirty percent circumferentially on the surface. Previous work done at NASA on molded fabric joints has shown that standard, NASA qualified polyester fabrics as are currently available in the textile industry for use in suits have a maximum of about fifteen percent draw ratio. NASA has done the fundamental design for a prototype joint and of a mold which would impart the correct shape to the fabric support layer of the joint. NASA also has the capability to test a finished product for suitability and reliability. Responsibilities resting with Georgia Tech in the design effort for this project are textile related, namely fiber selection, fabric design to achieve the properties of the objective design, and determining production means and sources for the fabrics. The project goals are to produce a prototype joint using the NASA design for evaluation of effectiveness by NASA, and to establish the sources and specifications which would allow reliable and repeatable production of the joint.

A Robotic Therapy Case Study: Developing Joint Attention Skills with a Student on the Autism Spectrum

ERIC Educational Resources Information Center

Charron, Nancy; Lewis, Lundy; Craig, Michael

2017-01-01

The purpose of this article is to describe a possible methodology for developing joint attention skills in students with autism spectrum disorder. Co-robot therapy with the humanoid robot NAO was used to foster a student's joint attention skill development; 20-min sessions conducted once weekly during the school year were video recorded and…

INTRA-ARTICULAR NERVE GROWTH FACTOR REGULATES DEVELOPMENT, BUT NOT MAINTENANCE, OF INJURY-INDUCED FACET JOINT PAIN & SPINAL NEURONAL HYPERSENSITIVITY

PubMed Central

Kras, Jeffrey V.; Kartha, Sonia; Winkelstein, Beth A.

2015-01-01

Objective The objective of the current study is to define whether intra-articular nerve growth factor (NGF), an inflammatory mediator that contributes to osteoarthritic pain, is necessary and sufficient for the development or maintenance of injury-induced facet joint pain and its concomitant spinal neuronal hyperexcitability. Method Male Holtzman rats underwent painful cervical facet joint distraction or sham procedures. Mechanical hyperalgesia was assessed in the forepaws, and NGF expression was quantified in the C6/C7 facet joint. An anti-NGF antibody was administered intra-articularly in additional rats immediately or 1 day following facet distraction or sham procedures to block intra-articular NGF and test its contribution to initiation and/or maintenance of facet joint pain and spinal neuronal hyperexcitability. NGF was injected into the bilateral C6/C7 facet joints in separate rats to determine if NGF alone is sufficient to induce these behavioral and neuronal responses. Results NGF expression increases in the cervical facet joint in association with behavioral sensitivity after that joint’s mechanical injury. Intra-articular application of anti-NGF immediately after a joint distraction prevents the development of both injury-induced pain and hyperexcitability of spinal neurons. Yet, intra-articular anti-NGF applied after pain has developed does not attenuate either behavioral or neuronal hyperexcitability. Intra-articular NGF administered to the facet in naïve rats also induces behavioral hypersensitivity and spinal neuronal hyperexcitability. Conclusion Findings demonstrate that NGF in the facet joint contributes to the development of injury-induced joint pain. Localized blocking of NGF signaling in the joint may provide potential treatment for joint pain. PMID:26521746

Development and laboratory testing of a 138-kV PPP-insulated joint for commercial application

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walldorf, S.P.; Chu, H.; Elbadaly, H.

1990-04-01

This paper describes the design, development and laboratory testing of a high voltage PPP (paper polypropylene/paper laminate) insulated joint for commercial application on 138-kV PPP-insulated cable. The design approach taken is conservative and addresses the typical variations in field conditions and in skill and workmanship of the splicing. Joint construction details, including choice of connector, taping structure, and joint mechanical reinforcement, are discussed. The test criteria are described and results are presented.

Finite element modelling predicts changes in joint shape and cell behaviour due to loss of muscle strain in jaw development

PubMed Central

Brunt, Lucy H.; Norton, Joanna L.; Bright, Jen A.; Rayfield, Emily J.; Hammond, Chrissy L.

2015-01-01

Abnormal joint morphogenesis is linked to clinical conditions such as Developmental Dysplasia of the Hip (DDH) and to osteoarthritis (OA). Muscle activity is known to be important during the developmental process of joint morphogenesis. However, less is known about how this mechanical stimulus affects the behaviour of joint cells to generate altered morphology. Using zebrafish, in which we can image all joint musculoskeletal tissues at high resolution, we show that removal of muscle activity through anaesthetisation or genetic manipulation causes a change to the shape of the joint between the Meckel's cartilage and Palatoquadrate (the jaw joint), such that the joint develops asymmetrically leading to an overlap of the cartilage elements on the medial side which inhibits normal joint function. We identify the time during which muscle activity is critical to produce a normal joint. Using Finite Element Analysis (FEA), to model the strains exerted by muscle on the skeletal elements, we identify that minimum principal strains are located at the medial region of the joint and interzone during mouth opening. Then, by studying the cells immediately proximal to the joint, we demonstrate that biomechanical strain regulates cell orientation within the developing joint, such that when muscle-induced strain is removed, cells on the medial side of the joint notably change their orientation. Together, these data show that biomechanical forces are required to establish symmetry in the joint during development. PMID:26253758

Finite element modelling predicts changes in joint shape and cell behaviour due to loss of muscle strain in jaw development.

PubMed

Brunt, Lucy H; Norton, Joanna L; Bright, Jen A; Rayfield, Emily J; Hammond, Chrissy L

2015-09-18

Abnormal joint morphogenesis is linked to clinical conditions such as Developmental Dysplasia of the Hip (DDH) and to osteoarthritis (OA). Muscle activity is known to be important during the developmental process of joint morphogenesis. However, less is known about how this mechanical stimulus affects the behaviour of joint cells to generate altered morphology. Using zebrafish, in which we can image all joint musculoskeletal tissues at high resolution, we show that removal of muscle activity through anaesthetisation or genetic manipulation causes a change to the shape of the joint between the Meckel's cartilage and Palatoquadrate (the jaw joint), such that the joint develops asymmetrically leading to an overlap of the cartilage elements on the medial side which inhibits normal joint function. We identify the time during which muscle activity is critical to produce a normal joint. Using Finite Element Analysis (FEA), to model the strains exerted by muscle on the skeletal elements, we identify that minimum principal strains are located at the medial region of the joint and interzone during mouth opening. Then, by studying the cells immediately proximal to the joint, we demonstrate that biomechanical strain regulates cell orientation within the developing joint, such that when muscle-induced strain is removed, cells on the medial side of the joint notably change their orientation. Together, these data show that biomechanical forces are required to establish symmetry in the joint during development. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Development of High Temperature Dissimilar Joint Technology for Fission Surface Power Systems

NASA Technical Reports Server (NTRS)

Locci, Ivan E.; Bowman, Cheryl L.; Gabb, Timothy P.

2009-01-01

NASA is developing fission surface power (FSP) system technology as a potential option for use on the surface of the moon or Mars. The goal is to design a robust system that takes full advantage of existing materials data bases. One of the key components of the power conversion system is the hot-side Heat Exchanger (HX). One possible design for this heat exchanger requires a joint of the dissimilar metals 316L stainless steel and Inconel 718, which must sustain extended operation at high temperatures. This study compares two joining techniques, brazing and diffusion bonding, in the context of forming the requisite stainless steel to superalloy joint. The microstructures produced by brazing and diffusion bonding, the effect of brazing cycle on the mechanical tensile properties of the alloys, and the strength of several brazed joints will be discussed.

Developing Joint Information Operations Warriors

DTIC Science & Technology

2006-04-13

the spectrum of conflict more than ever before. Information dominance has always been important, but the speed and methods at which it can be sent... information dominance . The analysis begins with a quick review of joint IO doctrine, Service approaches to IO, and IO personnel management. Next, IO

MULTIPLE NONSPECIFIC SITES OF JOINT PAIN OUTSIDE THE KNEES DEVELOP IN PERSONS WITH KNEE PAIN

PubMed Central

Felson, David T.; Niu, Jingbo; Quinn, Emily K; Neogi, Tuhina; Lewis, Cara; Lewis, Cora E.; Law, Laura Frey; McCulloch, Chuck; Nevitt, Michael; LaValley, Michael

2017-01-01

Objective Many persons with knee pain have joint pain outside the knee but despite the impact and high frequency of this pain, its distribution and causes have not been studied. Those studying gait abnormalities have suggested that knee pain causes pain in adjacent joints but pain adaptation strategies are highly individualized. Methods We studied persons age 50-79 years with or at high risk of knee osteoarthritis drawn from two community-based cohorts, the Multicenter Osteoarthritis Study and the Osteoarthritis Initiative and followed for 5-7 years. We excluded those with knee pain at baseline and compared those who developed and did not develop knee pain at the first follow-up examination (the index visit). We examined pain on most days at joint regions outside the knee in examinations after the index visit. Logistic regression analyses examined the risk of joint specific pain adjusted for age, sex, BMI, depression with sensitivity analyses excluding those with widespread pain. Results In the combined cohorts, there were 693 persons with index visit knee pain vs. 2793 without it. 79.6% of those with bilateral and 63.8% of those with unilateral knee pain had pain during follow-up in a joint region outside the knee vs. 49.9% of those without knee pain. An increased risk of pain was present in most extremity joint sites without a predilection for specific sites. Results were unchanged when those with widespread pain were excluded. Conclusions Persons with chronic knee pain are at increased risk of pain in multiple joints in no specific pattern. PMID:27589036

Development of the joint munitions planning system - a planning tool for the ammunition community.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hummel, J. R.; Winiecki, A. L.; Fowler, R. S.

2004-10-01

The United States Army Joint Munitions Command (JMC) is the executive agent for the Single Manager for Conventional Ammunition (SMCA). As such the JMC is responsible for the storage and transportation of all Service's SMCA as well as non-SMCA munitions. Part of the JMC mission requires that complex depot capacity studies, transportation capabilities analyses, peacetime re-allocations/ redistribution plans and time-phased deployment distribution plans be developed. Beginning in 1999 the Joint Munitions Planning System (JMPS) was developed to provide sourcing and movement solutions of ammunition for military planners.

24 CFR 570.411 - Joint Community Development Program.

Code of Federal Regulations, 2010 CFR

2010-04-01

... chief executive officer of each unit of general local government affected or a resolution of the... Availability described below in paragraph (h) of this section. (d) Role of participants in joint applications... will have to clearly delineate the role of each applicant in the joint application. Any funding...

15 CFR 295.23 - Dissolution of joint research and development ventures.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Dissolution of joint research and development ventures. 295.23 Section 295.23 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE NIST EXTRAMURAL...

15 CFR 295.23 - Dissolution of joint research and development ventures.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 15 Commerce and Foreign Trade 1 2012-01-01 2012-01-01 false Dissolution of joint research and development ventures. 295.23 Section 295.23 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE NIST EXTRAMURAL...

15 CFR 295.23 - Dissolution of joint research and development ventures.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 15 Commerce and Foreign Trade 1 2014-01-01 2014-01-01 false Dissolution of joint research and development ventures. 295.23 Section 295.23 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE NIST EXTRAMURAL...

15 CFR 295.23 - Dissolution of joint research and development ventures.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Dissolution of joint research and development ventures. 295.23 Section 295.23 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE NIST EXTRAMURAL...

15 CFR 295.23 - Dissolution of joint research and development ventures.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 15 Commerce and Foreign Trade 1 2013-01-01 2013-01-01 false Dissolution of joint research and development ventures. 295.23 Section 295.23 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE NIST EXTRAMURAL...

Degenerative joint disease: multiple joint involvement in young and mature dogs.

PubMed

Olsewski, J M; Lust, G; Rendano, V T; Summers, B A

1983-07-01

Radiologic, pathologic, and ancillary methods were used to determine the occurrence of degenerative joint disease involving multiple joints of immature and adult dogs. Animals were selected for the development of hip joint dysplasia and chronic degenerative joint disease. Of disease-prone dogs, 82% (45 of 55 dogs) had radiologic changes, indicative of hip dysplasia, by 1 year of age. At necropsy, more abnormal joints were identified than by radiographic examination. Among 92 dogs between 3 to 11 months of age that had joint abnormalities, 71% had hip joint involvement; 38%, shoulder joint involvement; 22%, stifle joint involvement; and 40% had multiple joint involvement. Polyarthritis was asymptomatic and unexpected. Radiographic examination of older dogs also revealed evidence of degenerative joint disease in many joints. Multiple joint involvement was substantiated at necropsy of young and mature dogs. A similar pattern of polyarticular osteoarthritis was revealed in a survey (computer search) of necropsy reports from medical case records of 100 adult and elderly dogs. Usually, the joint disease was an incidental observation, unrelated to the clinical disease or to the cause of death. The frequent occurrence of degenerative changes in several joints of dogs aged 6 months to 17 years indicated that osteoarthritis may be progressive in these joints and raises the possibility that systemic factors are involved in the disease process.

Towards an Analytical Framework for Understanding the Development of a Quality Assurance System in an International Joint Programme

ERIC Educational Resources Information Center

Zheng, Gaoming; Cai, Yuzhuo; Ma, Shaozhuang

2017-01-01

This paper intends to construct an analytical framework for understanding quality assurance in international joint programmes and to test it in a case analysis of a European--Chinese joint doctoral degree programme. The development of a quality assurance system for an international joint programme is understood as an institutionalization process…

Development of a Mandibular Motion Simulator for Total Joint Replacement

PubMed Central

Celebi, Nukhet; Rohner, E. Carlos; Gateno, Jaime; Noble, Philip C.; Ismaily, Sabir K.; Teichgraeber, John F.; Xia, James J.

2015-01-01

Purpose The purpose of this study was to develop a motion simulator capable of recreating and recording the full range of mandibular motions in a cadaveric preparation for an intact temporomandibular joint (TMJ) and after total joint replacement. Material and Methods A human cadaver head was used. Two sets of tracking balls were attached to the forehead and mandible, respectively. Computed tomographic (CT) scan was performed and 3-dimensional CT models of the skull were generated. The cadaver head was then dissected to attach the muscle activation cables and mounted onto the TMJ simulator. Realistic jaw motions were generated through the application of the following muscle forces: lateral pterygoid muscle, suprahyoid depressors (geniohyoid, mylohyoid, and digastric muscles), and elevator muscles. To simulate muscle contraction, cables were inserted into the mandible at the center area of each muscle's attachment. To provide a minimum mouth closing force at the initial position, the elevator muscles were combined at the anterior mandible. During mandibular movement, each motion was recorded using a high-resolution laser scanner. The right TMJ of the same head was reconstructed with a total TMJ prosthesis. The same forces were applied and the jaw motions were recorded again. CT scan was performed and 3-dimensional CT models of the skull with TMJ prosthesis were generated. Results Mandibular motions, before and after TMJ replacement, with and without lateral pterygoid muscle reattachment, were re-created in a cadaveric preparation. The laser-scanned data during the mandibular motion were used to drive 3-dimensional CT models. A movie for each mandibular motion was subsequently created for motion path analysis. Compared with mandibular motion before TMJ replacement, mandibular lateral and protrusive motions after TMJ replacement, with and without lateral pterygoid muscle reattachment, were greatly limited. The jaw motion recorded before total joint replacement was

Shear fracture of jointed steel plates of bolted joints under impact load

NASA Astrophysics Data System (ADS)

Daimaruya, M.; Fujiki, H.; Ambarita, H.; Kobayashi, H.; Shin, H.-S.

2013-07-01

The present study is concerned with the development of a fracture criterion for the impact fracture of jointed steel plates of bolted joints used in a car body, which contributes to crash simulations by CAE. We focus our attention on the shear fracture of the jointed steel plates of lap-bolted joints in the suspension of a car under impact load. Members of lap-bolted joints are modelled as a pair of steel plates connected by a bolt. One of the plates is a specimen subjected to plastic deformation and fracture and the other is a jig subjected to elastic deformation only. Three kinds of steel plate specimens are examined, i.e., a common steel plate with a tensile strength of 270 MPa and high tensile strength steel plates of 440 and 590 MPa used for cars. The impact shear test was performed using the split Hopkinson bar technique for tension impact, together with the static test using a universal testing machine INSTRON 5586. The behaviour of the shear stress and deformation up to rupture taking place in the joint was discussed. The obtained results suggest that a stress-based fracture criterion may be developed for the impact fracture of jointed steel plates of a lap-bolted joint.

Development of three-dimensional prints of arthritic joints for supporting patients' awareness to structural damage.

PubMed

Kleyer, Arnd; Beyer, Laura; Simon, Christoph; Stemmler, Fabian; Englbrecht, Matthias; Beyer, Christian; Rech, Jürgen; Manger, Bernhard; Krönke, Gerhard; Schett, Georg; Hueber, Axel J

2017-02-10

Rheumatoid arthritis (RA) and psoriatic arthritis (PsA) result in severe joint destruction and functional disability if left untreated. We aim to develop tools that help patients with RA and PsA to understand and experience the impact of inflammatory joint disease on the integrity of their (juxta-articular) bone and increase adherence to medical treatment. In this study, we used high-resolution peripheral quantitative computed tomography (HR-pQCT) to develop 3D prototypes of patients' finger joints. HR-pQCT (XtremeCT, Scanco) measurements were performed in healthy individuals and patients with inflammatory joint disease, followed by a 3D print using the objet30 printer. Healthy participants (n = 10), and patients (n = 15 with RA and 15 with PsA) underwent a detailed, standardized interview with demonstration of printed joints. Utilizing HR-pQCT images of metacarpophalangeal (MCP) heads, high quality and exact 3D prints as prototypes were created. Erosions in different sizes and the trabecular network printed in detail were visualized, demonstrating structural reduction in arthritic vs. healthy bone. After demonstration of 3D prints (healthy vs. erosive joint, visual and haptic) 26/39 (66%) participants (including healthy volunteers) were deeply affected, often quoting "shock". Of the patients with RA and PsA, 13/15 (86%) and 11/15 (73%), respectively, stated that they would rethink their attitude to medication adherence. More importantly, 21/24 patients with RA or PsA (87.5%) expressed that they would have wished to see such 3D prints during their first disease-specific conversations. Using arthro-haptic 3D printed prototypes of joints may help to better understand the impact of inflammatory arthritides on bone integrity and long-term damage.

Mechanical testing and development of the helical field coil joint for the Advanced Toroidal Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nelson, B.E.; Bryan, W.E.; Goranson, P.L.

1985-01-01

The helical field (HF) coil set for the Advanced Toroidal Facility (ATF) is an M = 12, l = 2, constant-ratio torsatron winding consisting of 2 coils, each with 14 turns of heavy copper conductor. The coils are divided into 24 identical segments to facilitate fabrication and minimize the assembly schedule. The segments are connected across through-bolted lap joints that must carry up to 124,000 A per turn for 5 s or 62,500 A steady-state. In addition, the joints must carry the high magnetic and thermal loads induced in the conductor and still fit within the basic 140- by 30-mmmore » copper envelope. Extensive testing and development were undertaken to verify and refine the basic joint design. Tests included assembly force and clamping force for various types of misalignment; joint resistance as a function of clamping force; clamp bolt relaxation due to thermal cycling; fatigue testing of full-size, multiturn joint prototypes; and low-cycle fatigue and tensile tests of annealed CDA102 copper. The required performance parameters and actual test results, as well as the final joint configuration, are presented. 2 refs., 9 figs., 4 tabs.« less

78 FR 20120 - Cooperative Research and Development Agreement: Joint Technical Demonstration of Tactical Data...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-03

... Development Agreement: Joint Technical Demonstration of Tactical Data Link Range Enhancement Software AGENCY... (TDL) range enhancement software technologies to improve operational effectiveness and communications... Range Enhancement Software Technologies, U.S. Coast Guard Research and Development Center, 1 Chelsea...

A Modelling Method of Bolt Joints Based on Basic Characteristic Parameters of Joint Surfaces

NASA Astrophysics Data System (ADS)

Yuansheng, Li; Guangpeng, Zhang; Zhen, Zhang; Ping, Wang

2018-02-01

Bolt joints are common in machine tools and have a direct impact on the overall performance of the tools. Therefore, the understanding of bolt joint characteristics is essential for improving machine design and assembly. Firstly, According to the experimental data obtained from the experiment, the stiffness curve formula was fitted. Secondly, a finite element model of unit bolt joints such as bolt flange joints, bolt head joints, and thread joints was constructed, and lastly the stiffness parameters of joint surfaces were implemented in the model by the secondary development of ABAQUS. The finite element model of the bolt joint established by this method can simulate the contact state very well.

Determination of Parachute Joint Factors using Seam and Joint Testing

NASA Technical Reports Server (NTRS)

Mollmann, Catherine

2015-01-01

This paper details the methodology for determining the joint factor for all parachute components. This method has been successfully implemented on the Capsule Parachute Assembly System (CPAS) for the NASA Orion crew module for use in determining the margin of safety for each component under peak loads. Also discussed are concepts behind the joint factor and what drives the loss of material strength at joints. The joint factor is defined as a "loss in joint strength...relative to the basic material strength" that occurs when "textiles are connected to each other or to metals." During the CPAS engineering development phase, a conservative joint factor of 0.80 was assumed for each parachute component. In order to refine this factor and eliminate excess conservatism, a seam and joint testing program was implemented as part of the structural validation. This method split each of the parachute structural joints into discrete tensile tests designed to duplicate the loading of each joint. Breaking strength data collected from destructive pull testing was then used to calculate the joint factor in the form of an efficiency. Joint efficiency is the percentage of the base material strength that remains after degradation due to sewing or interaction with other components; it is used interchangeably with joint factor in this paper. Parachute materials vary in type-mainly cord, tape, webbing, and cloth -which require different test fixtures and joint sample construction methods. This paper defines guidelines for designing and testing samples based on materials and test goals. Using the test methodology and analysis approach detailed in this paper, the minimum joint factor for each parachute component can be formulated. The joint factors can then be used to calculate the design factor and margin of safety for that component, a critical part of the design verification process.

Associations between joint attention and language in autism spectrum disorder and typical development: A systematic review and meta-regression analysis.

PubMed

Bottema-Beutel, Kristen

2016-10-01

Using a structured literature search and meta-regression procedures, this study sought to determine whether associations between joint attention and language are moderated by group (autism spectrum disorder [ASD] vs. typical development [TD]), joint attention type (responding to joint attention [RJA] vs. other), and other study design features and participant characteristics. Studies were located using database searches, hand searches, and electronic requests for data from experts in the field. This resulted in 71 reports or datasets and 605 effect sizes, representing 1,859 participants with ASD and 1,835 TD participants. Meta-regression was used to answer research questions regarding potential moderators of the effect sizes of interest, which were Pearson's r values quantifying the association between joint attention and language variables. In the final models, conducted separately for each language variable, effect sizes were significantly higher for the ASD group as compared to the TD group, and for RJA as compared to non-RJA joint attention types. Approximate mental age trended toward significance for the expressive language model. Joint attention may be more tightly tied to language in children with ASD as compared to TD children because TD children exhibit joint attention at sufficient thresholds so that language development becomes untethered to variations in joint attention. Conversely, children with ASD who exhibit deficits in joint attention develop language contingent upon their joint attention abilities. Because RJA was more strongly related to language than other types of joint attention, future research should involve careful consideration of the operationalization and measurement of joint attention constructs. Autism Res 2016, 9: 1021-1035. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

Minority Business Participation in Public/Private Partnerships: A Manual on Joint Development. Final Report.

ERIC Educational Resources Information Center

Beltran, Celestino M.; And Others

The Urban Mass Transportation Association promotes Commercial real estate development projects in and adjacent to transit facilities as a means of generating additional revenues to defray part of local transit agency operating cost. Transit-related real estate development, or joint development, provides unique financial benefits for investors and…

76 FR 1212 - Joint Biomedical Laboratory Research and Development and Clinical Science Research and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-07

... DEPARTMENT OF VETERANS AFFAIRS Joint Biomedical Laboratory Research and Development and Clinical Science Research and Development Services Scientific Merit Review Board Panel for Eligibility; Notice of Meeting The Department of Veterans Affairs (VA) gives notice under the Public Law 92-463 (Federal Advisory...

75 FR 57833 - Joint Biomedical Laboratory Research and Development and Clinical Science Research and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-22

... DEPARTMENT OF VETERANS AFFAIRS Joint Biomedical Laboratory Research and Development and Clinical Science Research and Development Services Scientific Merit Review Board; Notice of Meetings The Department of Veterans Affairs gives notice under the Public Law 92-463 (Federal Advisory Committee Act) that...

76 FR 66367 - Joint Biomedical Laboratory Research and Development and Clinical Science Research and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-26

... DEPARTMENT OF VETERANS AFFAIRS Joint Biomedical Laboratory Research and Development and Clinical Science Research and Development Services Scientific Merit Review Board; Notice of Meetings The Department of Veterans Affairs gives notice under the Public Law 92-463 (Federal Advisory Committee Act) that...

77 FR 26069 - Joint Biomedical Laboratory Research and Development and Clinical Science Research and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-02

... DEPARTMENT OF VETERANS AFFAIRS Joint Biomedical Laboratory Research and Development and Clinical Science Research and Development Services Scientific Merit Review Board, Notice of Meeting Amendment The Department of Veterans Affairs (VA) gives notice under the Public Law 92-463 (Federal Advisory Committee Act...

76 FR 79273 - Joint Biomedical Laboratory Research and Development and Clinical Science Research and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-21

... DEPARTMENT OF VETERANS AFFAIRS Joint Biomedical Laboratory Research and Development and Clinical Science Research and Development Services Scientific Merit Review Board Panel for Eligibility, Notice of Meeting The Department of Veterans Affairs (VA) gives notice under Public Law 92-463 (Federal Advisory...

78 FR 28292 - Joint Biomedical Laboratory Research and Development and Clinical Science Research and...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-14

... DEPARTMENT OF VETERANS AFFAIRS Joint Biomedical Laboratory Research and Development and Clinical Science Research and Development Services Scientific Merit Review Board; Notice of Meetings; Amendment The Department of Veterans Affairs (VA) gives notice under the Federal Advisory Committee Act, 5 U.S.C. App...

Second-site prosthetic joint infection in patients with multiple prosthetic joints.

PubMed

Clesham, Kevin; Hughes, Andrew J; O' hEireamhoin, Sven; Fleming, Catherine; Murphy, Colin G

2018-04-10

Prosthetic joint infections (PJIs) are among the most serious complications in arthroplasty. A second-site PJI in patients with multiple prosthetic joints increases morbidity, with many requiring further revision procedures. We aimed to establish why some patients with multiple joints develop second-site infections. Our institution's arthroplasty database was reviewed from 2004 to 2017. All PJIs were identified, and all patients with more than one prosthetic joint in situ were included. We recorded risk factors, causative organisms, number of procedures and length of stay. Forty-four patients meeting the criteria were identified. Four patients (9.1%) developed second-site infection. Eight patients (18.2%) developed re-infection of the primary PJI. Positive MRSA carrier status and PJI of a total knee replacement were associated with an increased risk of a second episode of infection. Patients who developed further infection had more frequent admission and longer lengths of stay than isolated PJIs. Higher morbidity and use of hospital resources are associated with this cohort of patients. PJIs in total knee replacements and positive MRSA status are associated with higher rates of second infection. Identifying this vulnerable cohort of patients at an early stage is critical to ensure measures are taken to reduce the risks of further infection.

Development of a persistent superconducting joint between Bi-2212/Ag-alloy multifilamentary round wires

NASA Astrophysics Data System (ADS)

Chen, Peng; Trociewitz, Ulf P.; Davis, Daniel S.; Bosque, Ernesto S.; Hilton, David K.; Kim, Youngjae; Abraimov, Dmytro V.; Starch, William L.; Jiang, Jianyi; Hellstrom, Eric E.; Larbalestier, David C.

2017-02-01

Superconducting joints are one of the key components needed to make Ag-alloy clad Bi2Sr2CaCu2O8+x (Bi-2212) superconducting round wire (RW) successful for high-field, high-homogeneity magnet applications, especially for nuclear magnetic resonance magnets in which persistent current mode operation is highly desired. In this study, a procedure for fabricating superconducting joints between Bi-2212 RWs during coil reaction was developed. Melting temperatures of Bi-2212 powder with different amounts of Ag addition were investigated by differential thermal analysis so as to provide information for selecting the proper joint matrix. Test joints of 1.3 mm dia. wires heat treated in 1 bar flowing oxygen using the typical partial melt Bi-2212 heat treatment (HT) had transport critical currents I c of ˜900 A at 4.2 K and self-field, decreasing to ˜480 A at 14 T evaluated at 0.1 μV cm-1 at 4.2 K. Compared to the I c of the open-ended short conductor samples with identical 1 bar HT, the I c values of the superconducting joint are ˜20% smaller than that of conductor samples measured in parallel field but ˜20% larger than conductor samples measured in perpendicular field. Microstructures examined by scanning electron microscopy clearly showed the formation of a superconducting Bi-2212 interface between the two Bi-2212 RWs. Furthermore, a Bi-2212 RW closed-loop solenoid with a superconducting joint heat treated in 1 bar flowing oxygen showed an estimated joint resistance below 5 × 10-12 Ω based on its field decay rate. This value is sufficiently low to demonstrate the potential for persistent operation of large inductance Bi-2212 coils.

Spry1 and Spry2 Are Essential for Development of the Temporomandibular Joint

PubMed Central

Purcell, P.; Jheon, A.; Vivero, M.P.; Rahimi, H.; Joo, A.; Klein, O.D.

2012-01-01

The temporomandibular joint (TMJ) is a specialized synovial joint essential for the function of the mammalian jaw. The main components of the TMJ are the mandibular condyle, the glenoid fossa of the temporal bone, and a fibrocartilagenous disc interposed between them. The genetic program for the development of the TMJ remains poorly understood. Here we show the crucial role of sprouty (Spry) genes in TMJ development. Sprouty genes encode intracellular inhibitors of receptor tyrosine kinase (RTK) signaling pathways, including those triggered by fibroblast growth factors (Fgfs). Using in situ hybridization, we show that Spry1 and Spry2 are highly expressed in muscles attached to the TMJ, including the lateral pterygoid and temporalis muscles. The combined inactivation of Spry1 and Spry2 results in overgrowth of these muscles, which disrupts normal development of the glenoid fossa. Remarkably, condyle and disc formation are not affected in these mutants, demonstrating that the glenoid fossa is not required for development of these structures. Our findings demonstrate the importance of regulated RTK signaling during TMJ development and suggest multiple skeletal origins for the fossa. Notably, our work provides the evidence that the TMJ condyle and disc develop independently of the mandibular fossa. PMID:22328578

Children's Developing Commitments to Joint Goals

ERIC Educational Resources Information Center

Hamann, Katharina; Warneken, Felix; Tomasello, Michael

2012-01-01

This study investigated young children's commitment to a joint goal by assessing whether peers in collaborative activities continue to collaborate until all received their rewards. Forty-eight 2.5- and 3.5-year-old children worked on an apparatus dyadically. One child got access to her reward early. For the partner to benefit as well, this child…

Maximum voluntary joint torque as a function of joint angle and angular velocity: model development and application to the lower limb.

PubMed

Anderson, Dennis E; Madigan, Michael L; Nussbaum, Maury A

2007-01-01

Measurements of human strength can be important during analyses of physical activities. Such measurements have often taken the form of the maximum voluntary torque at a single joint angle and angular velocity. However, the available strength varies substantially with joint position and velocity. When examining dynamic activities, strength measurements should account for these variations. A model is presented of maximum voluntary joint torque as a function of joint angle and angular velocity. The model is based on well-known physiological relationships between muscle force and length and between muscle force and velocity and was tested by fitting it to maximum voluntary joint torque data from six different exertions in the lower limb. Isometric, concentric and eccentric maximum voluntary contractions were collected during hip extension, hip flexion, knee extension, knee flexion, ankle plantar flexion and dorsiflexion. Model parameters are reported for each of these exertion directions by gender and age group. This model provides an efficient method by which strength variations with joint angle and angular velocity may be incorporated into comparisons between joint torques calculated by inverse dynamics and the maximum available joint torques.

Rating parent-child interactions: joint engagement, communication dynamics, and shared topics in autism, Down syndrome, and typical development.

PubMed

Adamson, Lauren B; Bakeman, Roger; Deckner, Deborah F; Nelson, P Brooke

2012-12-01

A battery of 17 rating items were applied to video records of typically-developing toddlers and young children with autism and Down syndrome interacting with their parents during the Communication Play Protocol. This battery provided a reliable and broad view of the joint engagement triad of child, partner, and shared topic. Ratings of the child's joint engagement correlated very strongly with state coding of joint engagement and replicated the finding that coordinated joint engagement was less likely in children with autism. Ratings of other child actions, of parent contributions, and of shared topics and communicative dynamics also documented pervasive variations related to diagnosis, language facility, and communicative context.

The Analysis of Adhesively Bonded Advanced Composite Joints Using Joint Finite Elements

NASA Technical Reports Server (NTRS)

Stapleton, Scott E.; Waas, Anthony M.

2012-01-01

The design and sizing of adhesively bonded joints has always been a major bottleneck in the design of composite vehicles. Dense finite element (FE) meshes are required to capture the full behavior of a joint numerically, but these dense meshes are impractical in vehicle-scale models where a course mesh is more desirable to make quick assessments and comparisons of different joint geometries. Analytical models are often helpful in sizing, but difficulties arise in coupling these models with full-vehicle FE models. Therefore, a joint FE was created which can be used within structural FE models to make quick assessments of bonded composite joints. The shape functions of the joint FE were found by solving the governing equations for a structural model for a joint. By analytically determining the shape functions of the joint FE, the complex joint behavior can be captured with very few elements. This joint FE was modified and used to consider adhesives with functionally graded material properties to reduce the peel stress concentrations located near adherend discontinuities. Several practical concerns impede the actual use of such adhesives. These include increased manufacturing complications, alterations to the grading due to adhesive flow during manufacturing, and whether changing the loading conditions significantly impact the effectiveness of the grading. An analytical study is conducted to address these three concerns. Furthermore, proof-of-concept testing is conducted to show the potential advantages of functionally graded adhesives. In this study, grading is achieved by strategically placing glass beads within the adhesive layer at different densities along the joint. Furthermore, the capability to model non-linear adhesive constitutive behavior with large rotations was developed, and progressive failure of the adhesive was modeled by re-meshing the joint as the adhesive fails. Results predicted using the joint FE was compared with experimental results for various

Structural tests and development of a laminar flow control wing surface composite chordwise joint

NASA Technical Reports Server (NTRS)

Lineberger, L. B.

1984-01-01

The dramatic increases in fuel costs and the potential for periods of limited fuel availability provided the impetus to explore technologies to reduce transport aircraft fuel consumption. NASA sponsored the Aircraft Energy Efficiency (ACEE) program beginning in 1976 to develop technologies to improve fuel efficiency. The Lockheed-Georgia Company accomplished under NAS1-16235 Laminar-Flow-Control (LFC) Wing Panel Structural Design and Development (WSSD); design, manufacturing, and testing activities. An in-depth preliminary design of the baseline 1993 LFC wing was accomplished. A surface panel using the Lockheed graphite/epoxy integrated LFC wing box structural concept was designed. The concept was shown by analysis to be structurally efficient and cost effective. Critical details of the surface and surface joint was demonstrated by fabricating and testing complex, concept selection specimens. The Lockheed-Georgia Company accomplishments, Development of LFC Wind Surface Composite Structures (WSCS), are documented. Tests were conducted on two CV2 panels to verify the static tension and fatigue strength of LFC wing surface chordwise joints.

Dynamic Analyses Including Joints Of Truss Structures

NASA Technical Reports Server (NTRS)

Belvin, W. Keith

1991-01-01

Method for mathematically modeling joints to assess influences of joints on dynamic response of truss structures developed in study. Only structures with low-frequency oscillations considered; only Coulomb friction and viscous damping included in analysis. Focus of effort to obtain finite-element mathematical models of joints exhibiting load-vs.-deflection behavior similar to measured load-vs.-deflection behavior of real joints. Experiments performed to determine stiffness and damping nonlinearities typical of joint hardware. Algorithm for computing coefficients of analytical joint models based on test data developed to enable study of linear and nonlinear effects of joints on global structural response. Besides intended application to large space structures, applications in nonaerospace community include ground-based antennas and earthquake-resistant steel-framed buildings.

Joint Attention Development in Low-risk Very Low Birth Weight Infants at Around 18 Months of Age.

PubMed

Yamaoka, Noriko; Takada, Satoshi

2016-10-18

The purpose of this study was to clarify the developmental characteristics of joint attention in very low birth weight (VLBW) infants with a low risk of complications. Section B of the Checklist for Autism in Toddlers (CHAT) was administered to 31 VLBW and 45 normal birth weight (NBW) infants aged 18-22 months, while the sessions were recorded with a video camera. A semi-structured observation scale was developed to assess infants' joint attention from the video footage, and was shown to be reliable. VLBW, compared to NBW, infants showed significantly poorer skills in 2 of 4 items on responding to joint attention, and in 6 of 10 items on initiating joint attention. VLBW infants need more clues in order to produce joint attention. The difficulty was attributed to insufficient verbal and fine motor function skills. Continuous follow-up evaluation is essential for both high-risk and low-risk VLBW infants and their parents.

Development of Thermal Barriers for Solid Rocket Motor Nozzle Joints

NASA Technical Reports Server (NTRS)

Steinetz, Bruce M.; Dunlap, Patrick H., Jr.

1999-01-01

The Space Shuttle solid rocket motor case assembly joints are sealed using conventional 0-ring seals. The 5500+F combustion gases are kept a safe distance away from the seals by thick layers of insulation. Special joint-fill compounds are used to fill the joints in the insulation to prevent a direct flowpath to the seals. On a number of occasions. NASA has observed in several of the rocket nozzle assembly joints hot gas penetration through defects in the joint- fill compound. The current nozzle-to-case joint design incorporates primary, secondary and wiper (inner-most) 0-rings and polysulfide joint-fill compound. In the current design, 1 out of 7 motors experience hot gas to the wiper 0-ring. Though the condition does not threaten motor safety, evidence of hot gas to the wiper 0-ring results in extensive reviews before resuming flight. NASA and solid rocket motor manufacturer Thiokol are working to improve the nozzle-to-case joint design by implementing a more reliable J-leg design and a thermal barrier, This paper presents burn-resistance, temperature drop, flow and resiliency test results for several types of NASA braided carbon-fiber thermal barriers. Burn tests were performed to determine the time to burn through each of the thermal barriers when exposed to the flame of an oxy-acetylene torch (5500 F), representative of the 5500 F solid rocket motor combustion temperatures. Thermal barriers braided out of carbon fibers endured the flame for over 6 minutes, three times longer than solid rocket motor burn time. Tests were performed on two thermal barrier braid architectures, denoted Carbon-3 and Carbon-6, to measure the temperature drop across and along the barrier in a compressed state when subjected to the flame of an oxyacetylene torch. Carbon-3 and Carbon-6 thermal barriers were excellent insulators causing temperature drops through their diameter of up to a 2800 and 2560 F. respectively. Gas temperature 1/4" downstream of the thermal barrier were within the

Objective Assessment of Joint Stiffness: A Clinically Oriented Hardware and Software Device with an Application to the Shoulder Joint.

PubMed

McQuade, Kevin; Price, Robert; Liu, Nelson; Ciol, Marcia A

2012-08-30

Examination of articular joints is largely based on subjective assessment of the "end-feel" of the joint in response to manually applied forces at different joint orientations. This technical report aims to describe the development of an objective method to examine joints in general, with specific application to the shoulder, and suitable for clinical use. We adapted existing hardware and developed laptop-based software to objectively record the force/displacement behavior of the glenohumeral joint during three common manual joint examination tests with the arm in six positions. An electromagnetic tracking system recorded three-dimensional positions of sensors attached to a clinician examiner and a patient. A hand-held force transducer recorded manually applied translational forces. The force and joint displacement were time-synchronized and the joint stiffness was calculated as a quantitative representation of the joint "end-feel." A methodology and specific system checks were developed to enhance clinical testing reproducibility and precision. The device and testing protocol were tested on 31 subjects (15 with healthy shoulders, and 16 with a variety of shoulder impairments). Results describe the stiffness responses, and demonstrate the feasibility of using the device and methods in clinical settings.

Development of brazing process for W-EUROFER joints using Cu-based fillers

NASA Astrophysics Data System (ADS)

de Prado, J.; Sánchez, M.; Ureña, A.

2016-02-01

A successful joint between W and EUROFER using high temperature brazing technique has been achieved for structural application in future fusion power plants. Cu-based powder alloy mixed with a polymeric binder has been used as filler. Microstructural analysis of the joints revealed that the joint consisted mainly of primary phases and acicular structures in a Cu matrix. Interaction between EUROFER and filler took place at the interface giving rise to several Cu-Ti-Fe rich layers. A loss of hardness at the EUROFER substrate close to the joint due to a diffusion phenomenon during brazing cycle was measured; however, the joints had an adequate shear strength value.

Structure and postembryonic development of the intersegmental nodules in the non-muscular joints of the antennae in Rhodnius prolixus.

PubMed

Ospina-Rozo, Bibiana; Forero-Shelton, Manu; Molina, Jorge

2017-03-01

The antennae of Insecta consist of two basal segments and the distal annulated flagellum lacking intrinsic muscles. Non-muscular joints are important to preserve the flexibility and structure of the long heteropteran antennae which bear an intersegmental nodule on each non-muscular joint. Little is known about their properties or function. Here we characterize the structure and postembryonic development of the non-muscular joints of Rhodnius prolixus antennae. Using Scanning Electron Microscopy, we tracked the changes in shape and size of both intersegmental nodules during the course of the hemimetabolous insect life cycle. Using Atomic Force Microscopy, we established a qualitative correlation between the topography of the surface and the rigidity of the joint between pedicel and flagellum. Our results confirmed the presence of two sub-articulations on each non-muscular joint. Also, the two intersegmental nodules have different origins: the one between the two flagellar segments (intraflagelloid) is a sclerite already present from the early nymph, while the nodule between pedicel and flagellum (prebasiflagellite) originates by gradual separation of the proximal end of the basiflagellum during postembryonic development. Various changes occur in the non-muscular joints and segments of the antenna during the life cycle of R. prolixus. Copyright © 2016 Elsevier Ltd. All rights reserved.

Normal radiological unossified hip joint space and femoral head size development during growth in 675 children and adolescents.

PubMed

Wegener, Veronika; Jorysz, Gabriele; Arnoldi, Andreas; Utzschneider, Sandra; Wegener, Bernd; Jansson, Volkmar; Heimkes, Bernhard

2017-03-01

Evaluation of hip joint space width during child growth is important to aid in the early diagnosis of hip pathology in children. We established reference values for hip joint space and femoral head size for each age. Hip joint space development during growth was retrospectively investigated medial and cranial in 1350 hip joints of children using standard anteroposterior supine plain pelvic radiographs. Maximum capital femoral epiphysis diameter and femoral radii were further more investigated. Hip joint space values show a slow decline during growth. Joint space was statistically significantly (p < 0.006) larger in boys than girls. Our hip joint space measurements on supine subjects seem slightly larger than those reported by Hughes on standing subjects. Evaluation of the femoral head diameter and the radii showed a size curve quite parallel to the known body growth charts. Radii medial and perpendicular to the physis are not statistically significantly different. We recommend to compare measurements of hip joint space at two locations to age dependent charts using the same imaging technique. During growth, a divergence in femoral head size from the expected values or loss of the spherical shape should raise the question of hip disorder. Clin. Anat. 30:267-275, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Predictors of Patient-Reported Outcomes of Total Joint Arthroplasty in a Developing Country.

PubMed

Bido, Jennifer; Yang, Ying H; Collins, Jamie E; Dong, Yan; Driscoll, Daniel A; Alcantara, Luis A; Thornhill, Thomas S; Katz, Jeffrey N

2017-06-01

In response to the growing burden of joint disease, developing countries are starting to create their own total joint arthroplasty (TJA) programs. To date, there has been limited research on predictors of TJA outcomes in a developing country. This investigation uses patient-reported outcome measures collected by a medical mission to assess predictors of TJA outcomes in the Dominican Republic. Baseline and postoperative information from 156 of the mission's recipients of hip and knee TJA was used. Demographics were abstracted from clinical notes, and self-reported pain and functional status were assessed using Western Ontario and McMaster University Osteoarthritis Index and Short-Form 36 measures. Bivariate analysis identified variables to include in multivariable regression models of factors associated with function and pain outcomes and improvement in these domains 1 or 2 years postoperatively. The cohort had a mean age of 61.3 years, 82% were female, 79% had total knee arthroplasty, and 42% of the procedures were bilateral. In multivariate analyses, at P < .05, male sex, better preoperative function, and use of bilateral procedure were associated with better functional outcome. Male sex and worse preoperative pain were associated with better pain outcome. Worse preoperative pain and function, as well as bilateral surgery were associated with greater improvement in function. Additionally, a greater number of bothersome joints was associated with greater pain reduction. Our findings of better follow-up pain scores among patients with worse pain preoperatively and better functional improvement among those undergoing bilateral replacements contrast with study results from developed countries. The explanations for these observations merit further study. Copyright © 2017 Elsevier Inc. All rights reserved.

Development and Applications of a Self-Contained, Non-Invasive EVA Joint Angle and Muscle Fatigue Sensor System

NASA Technical Reports Server (NTRS)

Ranniger, C. U.; Sorenson, E. A.; Akin, D. L.

1995-01-01

The University of Maryland Space Systems Laboratory, as a participant in NASA's INSTEP program, is developing a non-invasive, self-contained sensor system which can provide quantitative measurements of joint angles and muscle fatigue in the hand and forearm. The goal of this project is to develop a system with which hand/forearm motion and fatigue metrics can be determined in various terrestrial and zero-G work environments. A preliminary study of the prototype sensor systems and data reduction techniques for the fatigue measurement system are presented. The sensor systems evaluated include fiberoptics, used to measure joint angle, surface electrodes, which measure the electrical signals created in muscle as it contracts; microphones, which measure the noise made by contracting muscle; and accelerometers, which measure the lateral muscle acceleration during contraction. The prototype sensor systems were used to monitor joint motion of the metacarpophalangeal joint and muscle fatigue in flexor digitorum superficialis and flexor carpi ulnaris in subjects performing gripping tasks. Subjects were asked to sustain a 60-second constant-contraction (isometric) exercise and subsequently to perform a repetitive handgripping task to failure. Comparison of the electrical and mechanical signals of the muscles during the different tasks will be used to evaluate the applicability of muscle signal measurement techniques developed for isometric contraction tasks to fatigue prediction in quasi-dynamic exercises. Potential data reduction schemes are presented.

Multiple Nonspecific Sites of Joint Pain Outside the Knees Develop in Persons With Knee Pain.

PubMed

Felson, David T; Niu, Jingbo; Quinn, Emily K; Neogi, Tuhina; Lewis, Cara L; Lewis, Cora E; Frey Law, Laura; McCulloch, Chuck; Nevitt, Michael; LaValley, Michael

2017-02-01

Many persons with knee pain have joint pain outside the knee, but despite the impact and high frequency of this pain, its distribution and causes have not been studied. We undertook this study to test the hypothesis of those studying gait abnormalities who have suggested that knee pain causes pain in adjacent joints but that pain adaptation strategies are highly individualized. We studied persons ages 50-79 years with or at high risk of knee osteoarthritis who were recruited from 2 community-based cohorts, the Multicenter Osteoarthritis Study and the Osteoarthritis Initiative, and we followed them up for 5-7 years. We excluded those with knee pain at baseline and compared those who had developed knee pain at the first follow-up examination (the index visit) with those who had not. We examined pain on most days at joint regions outside the knee in examinations after the index visit. Logistic regression analyses examined the risk of joint-specific pain adjusted for age, sex, body mass index, and symptoms of depression, and we performed sensitivity analyses excluding those with widespread pain. In the combined cohorts, 693 persons had knee pain at the index visit and 2,793 did not. A total of 79.6% of those with bilateral knee pain and 63.8% of those with unilateral knee pain had pain during follow-up in a joint region outside the knee, compared with 49.9% of those without knee pain. There was an increased risk of pain at most extremity joint sites, without a predilection for specific sites. Results were unchanged when those with widespread pain were excluded. Persons with chronic knee pain are at increased risk of pain in multiple joints in no specific pattern. © 2016, American College of Rheumatology.

Ruminant methane reduction through livestock development in Tanzania. Final report for US Department of Energy and US Initiative on Joint Implementation--Activities Implemented Jointly

DOE Office of Scientific and Technical Information (OSTI.GOV)

Livingston, Roderick

1999-07-01

This project was designed to help develop the US Initiative on Joint Implementation activities in Eastern Africa. It has been communicated in meetings with representatives from the Ministry of Environment of Tanzania and the consultant group that developed Tanzania's National Climate Change Action Plan, the Centre for Energy, Environment, Science and Technology, that this project fits very well with the developmental and environmental goals of the Government of Tanzania. The goal of the Activities Implemented Jointly ruminant livestock project is to reduce ruminant methane emissions in Eastern Africa. The project plans a sustainable cattle multiplication unit (CMU) at Mabuki Ranchmore » in the Mwanza Region of Tanzania. This CMU will focus on raising genetically improved animals to be purchased by farmers, developmental organizations, and other CMUs in Tanzania. Through the purchase of these animals farmers will raise their income generation potential and reduce ruminant methane emissions.« less

Unloading joints to treat osteoarthritis, including joint distraction.

PubMed

Lafeber, Floris P J G; Intema, Femke; Van Roermund, Peter M; Marijnissen, Anne C A

2006-09-01

Patients are increasingly becoming interested in nonpharmacologic approaches to manage their osteoarthritis. This review examines the recent literature on the potential beneficial effects of unloading joints in the treatment of osteoarthritis, with a focus on joint distraction. Mechanical factors are involved in the development and progression of osteoarthritis. If "loading" is a major cause in development and progression of osteoarthritis, then "unloading" may be able to prevent progression. There is evidence that unloading may be effective in reducing pain and slowing down structural damage. This review describes unloading by footwear and bracing (nonsurgical), unloading by osteotomy (surgical), and has a focus on unloading by joint distraction. Excellent reviews in all these three fields have been published over the past few years. Recent studies argue for the usefulness of a biomechanical approach to improve function and possibly reduce disease progression in osteoarthritis. To improve patient function and possibly reduce disease progression, a biomechanical approach should be considered in treating patients with osteoarthritis. Further research (appropriate high-quality clinical trials) and analysis (clinical as well as preclinical and fundamental) are still necessary, however, to understand, validate, and refine the different approaches of unloading to treat osteoarthritis.

A Review of Natural Joint Systems and Numerical Investigation of Bio-Inspired GFRP-to-Steel Joints

PubMed Central

Avgoulas, Evangelos I.; Sutcliffe, Michael P. F.

2016-01-01

There are a great variety of joint types used in nature which can inspire engineering joints. In order to design such biomimetic joints, it is at first important to understand how biological joints work. A comprehensive literature review, considering natural joints from a mechanical point of view, was undertaken. This was used to develop a taxonomy based on the different methods/functions that nature successfully uses to attach dissimilar tissues. One of the key methods that nature uses to join dissimilar materials is a transitional zone of stiffness at the insertion site. This method was used to propose bio-inspired solutions with a transitional zone of stiffness at the joint site for several glass fibre reinforced plastic (GFRP) to steel adhesively bonded joint configurations. The transition zone was used to reduce the material stiffness mismatch of the joint parts. A numerical finite element model was used to identify the optimum variation in material stiffness that minimises potential failure of the joint. The best bio-inspired joints showed a 118% increase of joint strength compared to the standard joints. PMID:28773688

A Review of Natural Joint Systems and Numerical Investigation of Bio-Inspired GFRP-to-Steel Joints.

PubMed

Avgoulas, Evangelos I; Sutcliffe, Michael P F

2016-07-12

There are a great variety of joint types used in nature which can inspire engineering joints. In order to design such biomimetic joints, it is at first important to understand how biological joints work. A comprehensive literature review, considering natural joints from a mechanical point of view, was undertaken. This was used to develop a taxonomy based on the different methods/functions that nature successfully uses to attach dissimilar tissues. One of the key methods that nature uses to join dissimilar materials is a transitional zone of stiffness at the insertion site. This method was used to propose bio-inspired solutions with a transitional zone of stiffness at the joint site for several glass fibre reinforced plastic (GFRP) to steel adhesively bonded joint configurations. The transition zone was used to reduce the material stiffness mismatch of the joint parts. A numerical finite element model was used to identify the optimum variation in material stiffness that minimises potential failure of the joint. The best bio-inspired joints showed a 118% increase of joint strength compared to the standard joints.

Self-Alining Quick-Connect Joint

NASA Technical Reports Server (NTRS)

Lucy, M. H.

1983-01-01

Quick connect tapered joint used with minimum manipulation and force. Split ring retainer holds locking ring in place. Minimal force required to position male in female joint, at which time split-ring retainers are triggered to release split locking rings. Originally developed to assemble large space structures, joint is simple, compact, strong, lightweight, self alining, and has no loose parts.

Finger-Jointed Wood Products.

DTIC Science & Technology

1981-04-01

these melamines do not have the same Urea resins are generally marketed adhesives does not always develop resistance to weathering as do in liquid form...OF durable, colorless glueline is required. been developed for use in RF curing. FINGER JOINTS MelamineUrea Resins IN STRUCTURAL Melamine - urea resins ...finger duced either by dry blending urea and moplastic, softening if temperature is joints, strength is expressed as a melamine resins or by blending

Development of remountable joints and heat removable techniques for high-temperature superconducting magnets

NASA Astrophysics Data System (ADS)

Hashizume, H.; Ito, S.; Yanagi, N.; Tamura, H.; Sagara, A.

2018-02-01

Segment fabrication is now a candidate for the design of superconducting helical magnets in the helical fusion reactor FFHR-d1, which adopts the joint winding of high-temperature superconducting (HTS) helical coils as a primary option and the ‘remountable’ HTS helical coil as an advanced option. This paper reports on recent progress in two key technologies: the mechanical joints (remountable joints) of the HTS conductors and the metal porous media inserted into the cooling channel for segment fabrication. Through our research activities it has been revealed that heat treatment during fabrication of the joint can reduce joint resistance and its dispersion, which can shorten the fabrication process and be applied to bent conductor joints. Also, heat transfer correlations of the cooling channel were established to evaluate heat transfer performance with various cryogenic coolants based on the correlations to analyze the thermal stability of the joint.

Shoulder Joint For Protective Suit

NASA Technical Reports Server (NTRS)

Kosmo, Joseph J.; Smallcombe, Richard D.

1994-01-01

Shoulder joint allows full range of natural motion: wearer senses little or no resisting force or torque. Developed for space suit, joint offers advantages in protective garments for underwater work, firefighting, or cleanup of hazardous materials.

Research Review: Social motivation and oxytocin in autism – implications for joint attention development and intervention

PubMed Central

Stavropoulos, Katherine K. M.; Carver, Leslie J.

2013-01-01

Background and Scope The social motivation hypothesis (SMH) suggests that individuals with autism spectrum disorders (ASD) are less intrinsically rewarded by social stimuli than their neurotypical peers. This difference in social motivation has been posited as a factor contributing to social deficits in ASD. Social motivation is thought to involve the neuropeptide oxytocin. Here, we review the evidence for oxytocin effects in ASD, and discuss its potential role in one important social cognitive behavior. Methods Systematic searches were conducted using the PsychINFO and MEDLINE databases and the search terms “oxytocin”, and “autism”; the same databases were used for separate searches for “joint attention”, “intervention”, and “autism”, using the same inclusion criteria as an earlier 2011 review but updating it for the period 2010 to October 2012. Findings Several studies suggest that giving oxytocin to both individuals with ASD and typically developing individuals can enhance performance on social cognitive tasks. Studies that have attempted to intervene in joint attention in ASD suggest that social motivation may be a particular obstacle to lasting effects. Conclusions The review of the evidence for the SMH suggests a potential role for oxytocin in social motivation deficits in ASD. Because of its importance for later communicative and social development, the focus here is on implications of oxytocin and social motivation in the development of and interventions in joint attention. Joint attention is a central impairment in ASD, and as a result is the focus of several behavioral interventions. In describing this previous research on joint attention interventions in ASD, we pay particular attention to problems encountered in such studies, and propose ways that oxytocin may facilitate behavioral intervention in this area. For future research, integrating behavioral and pharmacological interventions (oxytocin administration) would be a worthwhile

Computer simulation of solder joint failure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burchett, S.N.; Frear, D.R.; Rashid, M.M.

The thermomechanical fatigue failure of solder joints is increasingly becoming an important reliability issue for electronic packages. The purpose of this Laboratory Directed Research and Development (LDRD) project was to develop computational tools for simulating the behavior of solder joints under strain and temperature cycling, taking into account the microstructural heterogeneities that exist in as-solidified near eutectic Sn-Pb joints, as well as subsequent microstructural evolution. The authors present two computational constitutive models, a two-phase model and a single-phase model, that were developed to predict the behavior of near eutectic Sn-Pb solder joints under fatigue conditions. Unique metallurgical tests provide themore » fundamental input for the constitutive relations. The two-phase model mathematically predicts the heterogeneous coarsening behavior of near eutectic Sn-Pb solder. The finite element simulations with this model agree qualitatively with experimental thermomechanical fatigue tests. The simulations show that the presence of an initial heterogeneity in the solder microstructure could significantly degrade the fatigue lifetime. The single-phase model was developed to predict solder joint behavior using materials data for constitutive relation constants that could be determined through straightforward metallurgical experiments. Special thermomechanical fatigue tests were developed to give fundamental materials input to the models, and an in situ SEM thermomechanical fatigue test system was developed to characterize microstructural evolution and the mechanical behavior of solder joints during the test. A shear/torsion test sample was developed to impose strain in two different orientations. Materials constants were derived from these tests. The simulation results from the two-phase model showed good fit to the experimental test results.« less

Effects of joints in truss structures

NASA Technical Reports Server (NTRS)

Ikegami, R.

1988-01-01

The response of truss-type structures for future space applications, such as Large Deployable Reflector (LDR), will be directly affected by joint performance. Some of the objectives of research at BAC were to characterize structural joints, establish analytical approaches that incorporate joint characteristics, and experimentally establish the validity of the analytical approaches. The test approach to characterize joints for both erectable and deployable-type structures was based upon a Force State Mapping Technique. The approach pictorially shows how the nonlinear joint results can be used for equivalent linear analysis. Testing of the Space Station joints developed at LaRC (a hinged joint at 2 Hz and a clevis joint at 2 Hz) successfully revealed the nonlinear characteristics of the joints. The Space Station joints were effectively linear when loaded to plus or minus 500 pounds with a corresponding displacement of about plus or minus 0.0015 inch. It was indicated that good linear joints exist which are compatible with errected structures, but that difficulty may be encountered if nonlinear-type joints are incorporated in the structure.

Development of Stable, Low Resistance Solder Joints for a Space-Flight HTS Lead Assemblies

NASA Technical Reports Server (NTRS)

Canavan, Edgar R.; Chiao, Meng; Panashchenko, Lyudmyla; Sampson, Michael

2017-01-01

The solder joints in spaceflight high temperature superconductor (HTS) lead assemblies for certain astrophysics missions have strict constraints on size and power dissipation. In addition, the joints must tolerate years of storage at room temperature, many thermal cycles, and several vibration tests between their manufacture and their final operation on orbit. As reported previously, solder joints between REBCO coated conductors and normal metal traces for the Astro-H mission showed low temperature joint resistance that grew approximately as log time over the course of months. Although the assemblies worked without issue in orbit, for the upcoming X-ray Astrophysics Recovery Mission we are attempting to improve our solder process to give lower, more stable, and more consistent joint resistance. We produce numerous sample joints and measure time- and thermal cycle-dependent resistance, and characterize the joints using x-ray and other analysis tools. For a subset of the joints, we use SEMEDS to try to understand the physical and chemical processes that effect joint behavior.

Relationship of medial gastrocnemius relative fascicle excursion and ankle joint power and work performance during gait in typically developing children

PubMed Central

Martín Lorenzo, Teresa; Albi Rodríguez, Gustavo; Rocon, Eduardo; Martínez Caballero, Ignacio; Lerma Lara, Sergio

2017-01-01

Abstract Muscle fascicles lengthen in response to chronic passive stretch through in-series sarcomere addition in order to maintain an optimum sarcomere length. In turn, the muscles’ force generating capacity, maximum excursion, and contraction velocity is enhanced. Thus, longer fascicles suggest a greater capacity to develop joint power and work. However, static fascicle length measurements may not be taking sarcomere length differences into account. Thus, we considered relative fascicle excursions through passive ankle dorsiflexion may better correlate with the capacity to generate joint power and work than fascicle length. Therefore, the aim of the present study was to determine if medial gastrocnemius relative fascicle excursions correlate with ankle joint power and work generation during gait in typically developing children. A sample of typically developing children (n = 10) were recruited for this study and data analysis was carried out on 20 legs. Medial gastrocnemius relative fascicle excursion from resting joint angle to maximum dorsiflexion was estimated from trigonometric relations of medial gastrocnemius pennation angle and thickness obtained from B-mode real-time ultrasonography. Furthermore, a three-dimensional motion capture system was used to obtain ankle joint work and power during the stance phase of gait. Significant correlations were found between relative fascicle excursion and peak power absorption (–) r(14) = −0.61, P = .012 accounting for 31% variability, positive work r(18) = 0.56, P = .021 accounting for 31% variability, and late stance positive work r(15) = 0.51, P = .037 accounting for 26% variability. The large unexplained variance may be attributed to mechanics of neighboring structures (e.g., soleus or Achilles tendon mechanics) and proximal joint kinetics which may also contribute to ankle joint power and work performance, and were not taken into account. Further studies are encouraged to provide

Research review: Social motivation and oxytocin in autism--implications for joint attention development and intervention.

PubMed

Stavropoulos, Katherine K M; Carver, Leslie J

2013-06-01

The social motivation hypothesis (SMH) suggests that individuals with autism spectrum disorders (ASD) are less intrinsically rewarded by social stimuli than their neurotypical peers. This difference in social motivation has been posited as a factor contributing to social deficits in ASD. Social motivation is thought to involve the neuropeptide oxytocin. Here, we review the evidence for oxytocin effects in ASD, and discuss its potential role in one important social cognitive behavior. Systematic searches were conducted using the PsychINFO and MEDLINE databases and the search terms 'oxytocin' and 'autism'; the same databases were used for separate searches for 'joint attention', 'intervention', and 'autism', using the same inclusion criteria as an earlier 2011 review but updating it for the period 2010 to October 2012. Several studies suggest that giving oxytocin to both individuals with ASD and neurotypical individuals can enhance performance on social cognitive tasks. Studies that have attempted to intervene in joint attention in ASD suggest that social motivation may be a particular obstacle to lasting effects. The review of the evidence for the SMH suggests a potential role for oxytocin in social motivation deficits in ASD. Because of its importance for later communicative and social development, the focus here is on implications of oxytocin and social motivation in the development of and interventions in joint attention. Joint attention is a central impairment in ASD, and as a result is the focus of several behavioral interventions. In describing this previous research on joint attention interventions in ASD, we pay particular attention to problems encountered in such studies, and propose ways that oxytocin may facilitate behavioral intervention in this area. For future research, integrating behavioral and pharmacological interventions (oxytocin administration) would be a worthwhile experimental direction to improve understanding of the role of oxytocin in ASD

Joint Military Education: Actions Needed to Implement DOD Recommendations for Enhancing Leadership Development

DTIC Science & Technology

2013-10-01

Joint Chiefs of Staff. The university conducts JPME seminars, symposia, and professional development and conferencing for DOD and Congressional...all enlisted personnel. Basic Enlisted JPME addresses educational guidelines that should be completed by pay grade E -6,20 while Career Enlisted JPME...addresses educational guidelines for senior enlisted personnel in grades E -6 or E -7 and above. Beyond these

Note: Progress on the use of MgB2 superconducting joint technique for the development of MgB2 magnets for magnetic resonance imaging (MRI).

PubMed

Kim, Y G; Song, J B; Kim, J C; Kim, J M; Yoo, B H; Yun, S B; Hwang, D Y; Lee, H G

2017-08-01

This note presents a superconducting joint technique for the development of MgB 2 magnetic resonance imaging (MRI) magnets. The MgB 2 superconducting joint was fabricated by a powder processing method using Mg and B powders to establish a wire-bulk-wire connection. The joint resistance measured using a field-decay method was <10 -14 Ω, demonstrating that the proposed joint technique could be employed for developing "next-generation" MgB 2 MRI magnets operating in the persistent current mode.

Observing the development of the temporomandibular joint in embryonic and post-natal mice using various staining methods

PubMed Central

LIANG, WENNA; LI, XIHAI; GAO, BIZHEN; GAN, HUIJUAN; LIN, XUEJUAN; LIAO, LINGHONG; LI, CANDONG

2016-01-01

The temporomandibular joint (TMJ) is a specialized synovial joint that is essential for the movement and function of the mammalian jaw. The TMJ develops from two mesenchymal condensations, and is composed of the glenoid fossa that originates from the otic capsule by intramembranous ossification, the mandibular condyle of the temporal bone and a fibrocartilagenous articular disc derived from a secondary cartilaginous joint by endochondral ossification. However, the development of the TMJ remains unclear. In the present study, the formation and development of the mouse TMJ was investigated between embryonic day 13.5 and post-natal day 180 in order to elucidate the morphological and molecular alterations that occur during this period. TMJ formation appeared to proceed in three stages: Initiation or blastema stage; growth and cavitation stage; and the maturation or completion stage. In order to investigate the activity of certain transcription factors on TMJ formation and development, the expression of extracellular matrix (ECM), sex determining region Y-box 9, runt-related transcription factor 2, Indian hedgehog homolog, Osterix, collagen I, collagen II, aggrecan, total matrix metalloproteinase (MMP), MMP-9 and MMP-13 were detected in the TMJ using in situ and/or immunohistochemistry. The results indicate that the transcription factors, ECM and MMP serve critical functions in the formation and development of the mouse TMJ. In summary, the development of the mouse TMJ was investigated, and the molecular regulation of mouse TMJ formation was partially characterized. The results of the present study may aid the systematic understanding of the physiological processes underlying TMJ formation and development in mice. PMID:26893634

[Effects of exercise on joints.

PubMed

Moriyama, Hideki

Joints are composed of several different tissues(cartilage, capsule, meniscus, and ligament), and articular cartilage plays an important role in maintaining mechanical competence during exercise. Weight-bearing exercise has several benefit, including improved blood and synovial fluid circulation in a given joint. Consistent moderate activities facilitate cycles of anabolism and catabolism. Mechanical stresses are crucial for the maintenance of the morphologic and functional integrity of articular cartilage. Healthy cartilage is exposed by hydrostatic pressure and tensile strain, when cartilage degeneration develops, abnormal cartilage is exposed by shear stress. Moderate(physiological)exercise is characterized by a range of equilibrium between matrix anabolic and catabolic processes, or anabolism beyond catabolism. Joints are susceptible to insufficient or excessive activities, leading to joint degeneration. Lack of exercise is known to induce joint contracture seen clinically as a consequence of disuse changes, and excess mechanical stresses induce joint destruction such as osteoarthritis. Joint diseases resulting from insufficient or excessive activities are new and major challenging issues with our aging population. Thus, it is highly desirable to have an effective and efficient treatment to improve and protect against these joint diseases, and thereby to solve these clearly unanswered issues.

Development of an Underactuated 2-DOF Wrist Joint using McKibben PAMs

NASA Astrophysics Data System (ADS)

Rajagopal, S. P.; Jain, S.; Ramasubramanian, S. N.; Johnson, B. V.; Dwivedy, S. K.

2014-10-01

In this work, model of an underactuated 2-DOF wrist joint with pneumatically actuated muscles is proposed. For the joint, McKibben-type artificial muscles are used in parallel configuration for the actuation. For each Degree of Freedom (DOF) one agonist-antagonist pair arrangement is usually used with a pulley mechanism. A mathematical model of wrist joint is derived using conventional forward kinematic analysis. The static model relating pressure in the muscle with the orientation of the wrist joint is obtained by combining the experimental data and mathematical model. Regulation of pressure can be achieved by pulse width modulation control of on/off solenoid valves. A set of free vibration experiments are done for the dynamic identification of the muscle characteristics.

Joint ventures: to pursue or not to pursue?

PubMed

Blaszyk, Michael D; Hill-Mischel, Jody

2007-11-01

Hospitals should carefully select joint venture partners. The joint venture evaluation process should involve a high-level screen of strategic opportunities. Hospitals should develop a full business plan for the joint venture.

A New Vector for Air Force Development of Joint Leaders

DTIC Science & Technology

2010-05-26

congressional sanction and a formal definition by the President, the JCS was comprised of the US counterparts to the British leaders of the army, navy, and...hostages held in the US Embassy in Tehran. The operation ended in disaster at the Desert One landing zone when a Navy helicopter piloted by marines...minded, critical thinkers.” The CJCS vision focuses building a pool of joint generalists by inculcation of jointness at the rank of colonel and

Tissue interaction is required for glenoid fossa development during temporomandibular joint formation

PubMed Central

Wang, Ying; Liu, Chao; Rohr, Joseph; Liu, Hongbing; He, Fenglei; Yu, Jian; Sun, Cheng; Li, Lu; Gu, Shuping; Chen, YiPing

2011-01-01

The mammalian temporomandibular joint (TMJ) develops from two distinct mesenchymal condensations that grow towards each other and ossify through different mechanisms, with the glenoid fossa undergoing intramembranous ossification while the condyle being endochondral in origin. In this study, we used various genetically modified mouse models to investigate tissue interaction between the condyle and glenoid fossa during TMJ formation in mice. We report that either absence or dislocation of the condyle results in an arrested glenoid fossa development. In both cases, glenoid fossa development was initiated, but failed to sustain, and became regressed subsequently. However, condyle development appears to be independent upon the presence of the forming glenoid fossa. In addition, we show that substitution of condyle by Meckel’s cartilage is able to sustain glenoid fossa development. These observations suggest that proper signals from the developing condyle or Meckel’s cartilage are required to sustain the glenoid fossa development. PMID:21953591

Joint attention and language evolution

NASA Astrophysics Data System (ADS)

Kwisthout, Johan; Vogt, Paul; Haselager, Pim; Dijkstra, Ton

2008-06-01

This study investigates how more advanced joint attentional mechanisms, rather than only shared attention between two agents and an object, can be implemented and how they influence the results of language games played by these agents. We present computer simulations with language games showing that adding constructs that mimic the three stages of joint attention identified in children's early development (checking attention, following attention, and directing attention) substantially increase the performance of agents in these language games. In particular, the rates of improved performance for the individual attentional mechanisms have the same ordering as that of the emergence of these mechanisms in infants' development. These results suggest that language evolution and joint attentional mechanisms have developed in a co-evolutionary way, and that the evolutionary emergence of the individual attentional mechanisms is ordered just like their developmental emergence.

Prosthetic joint infection development of an evidence-based diagnostic algorithm.

PubMed

Mühlhofer, Heinrich M L; Pohlig, Florian; Kanz, Karl-Georg; Lenze, Ulrich; Lenze, Florian; Toepfer, Andreas; Kelch, Sarah; Harrasser, Norbert; von Eisenhart-Rothe, Rüdiger; Schauwecker, Johannes

2017-03-09

Increasing rates of prosthetic joint infection (PJI) have presented challenges for general practitioners, orthopedic surgeons and the health care system in the recent years. The diagnosis of PJI is complex; multiple diagnostic tools are used in the attempt to correctly diagnose PJI. Evidence-based algorithms can help to identify PJI using standardized diagnostic steps. We reviewed relevant publications between 1990 and 2015 using a systematic literature search in MEDLINE and PUBMED. The selected search results were then classified into levels of evidence. The keywords were prosthetic joint infection, biofilm, diagnosis, sonication, antibiotic treatment, implant-associated infection, Staph. aureus, rifampicin, implant retention, pcr, maldi-tof, serology, synovial fluid, c-reactive protein level, total hip arthroplasty (THA), total knee arthroplasty (TKA) and combinations of these terms. From an initial 768 publications, 156 publications were stringently reviewed. Publications with class I-III recommendations (EAST) were considered. We developed an algorithm for the diagnostic approach to display the complex diagnosis of PJI in a clear and logically structured process according to ISO 5807. The evidence-based standardized algorithm combines modern clinical requirements and evidence-based treatment principles. The algorithm provides a detailed transparent standard operating procedure (SOP) for diagnosing PJI. Thus, consistently high, examiner-independent process quality is assured to meet the demands of modern quality management in PJI diagnosis.

Determination of representative dimension parameter values of Korean knee joints for knee joint implant design.

PubMed

Kwak, Dai Soon; Tao, Quang Bang; Todo, Mitsugu; Jeon, Insu

2012-05-01

Knee joint implants developed by western companies have been imported to Korea and used for Korean patients. However, many clinical problems occur in knee joints of Korean patients after total knee joint replacement owing to the geometric mismatch between the western implants and Korean knee joint structures. To solve these problems, a method to determine the representative dimension parameter values of Korean knee joints is introduced to aid in the design of knee joint implants appropriate for Korean patients. Measurements of the dimension parameters of 88 male Korean knee joint subjects were carried out. The distribution of the subjects versus each measured parameter value was investigated. The measured dimension parameter values of each parameter were grouped by suitable intervals called the "size group," and average values of the size groups were calculated. The knee joint subjects were grouped as the "patient group" based on "size group numbers" of each parameter. From the iterative calculations to decrease the errors between the average dimension parameter values of each "patient group" and the dimension parameter values of the subjects, the average dimension parameter values that give less than the error criterion were determined to be the representative dimension parameter values for designing knee joint implants for Korean patients.

Hyaluronan supplementation as a mechanical regulator of cartilage tissue development under joint-kinematic-mimicking loading.

PubMed

Wu, Yabin; Stoddart, Martin J; Wuertz-Kozak, Karin; Grad, Sibylle; Alini, Mauro; Ferguson, Stephen J

2017-08-01

Articular cartilage plays an essential role in joint lubrication and impact absorption. Through this, the mechanical signals are coupled to the tissue's physiological response. Healthy synovial fluid has been shown to reduce and homogenize the shear stress acting on the cartilage surfaces due to its unique shear-thinning viscosity. As cartilage tissues are sensitive to mechanical changes in articulation, it was hypothesized that replacing the traditional culture medium with a healthy non-Newtonian lubricant could enhance tissue development in a cartilage engineering model, where joint-kinematic-mimicking mechanical loading is applied. Different amounts of hyaluronic acid were added to the culture medium to replicate the viscosities of synovial fluid at different health states. Hyaluronic acid supplementation, especially at a physiologically healthy concentration (2.0 mg ml -1 ), promoted a better preservation of chondrocyte phenotype. The ratio of collagen II to collagen I mRNA was 4.5 times that of the control group, implying better tissue development (however, with no significant difference of measured collagen II content), with a good retention of collagen II and proteoglycan in the mechanically active region. Simulating synovial fluid properties by hyaluronic acid supplementation created a favourable mechanical environment for mechanically loaded constructs. These findings may help in understanding the influence of joint articulation on tissue homeostasis, and moreover, improve methods for functional cartilage tissue engineering. © 2017 The Author(s).

Biomimetic-inspired joining of composite with metal structures: A survey of natural joints and application to single lap joints

NASA Astrophysics Data System (ADS)

Avgoulas, Evangelos Ioannis; Sutcliffe, Michael P. F.

2014-03-01

Joining composites with metal parts leads, inevitably, to high stress concentrations because of the material property mismatch. Since joining composite to metal is required in many high performance structures, there is a need to develop a new multifunctional approach to meet this challenge. This paper uses the biomimetics approach to help develop solutions to this problem. Nature has found many ingenious ways of joining dissimilar materials and making robust attachments, alleviating potential stress concentrations. A literature survey of natural joint systems has been carried out, identifying and analysing different natural joint methods from a mechanical perspective. A taxonomy table was developed based on the different methods/functions that nature successfully uses to attach dissimilar tissues (materials). This table is used to understand common themes or approaches used in nature for different joint configurations and functionalities. One of the key characteristics that nature uses to joint dissimilar materials is a transitional zone of stiffness in the insertion site. Several biomimetic-inspired metal-to-composite (steel-to-CFRP), adhesively bonded, Single Lap Joints (SLJs) were numerically investigated using a finite element analysis. The proposed solutions offer a transitional zone of stiffness of one joint part to reduce the material stiffness mismatch at the joint. An optimisation procedure was used to identify the variation in material stiffness which minimises potential failure of the joint. It was found that the proposed biomimetic SLJs reduce the asymmetry of the stress distribution along the adhesive area.

Development of the Joint Committee Standards for Evaluations of Educational Programs, Projects, and Materials.

ERIC Educational Resources Information Center

Diamond, Esther E.

The growing demand for program evaluation in the 1970s gave rise to a need for a comprehensive, carefully developed, objective set of guiding principles for the evaluation process, from initial planning to final report. The Joint Committee on Standards for Education Evaluation was established to meet this need. This broad-based group, representing…

A Note on the Purposes, Development, and Applicability of the Joint Committee Evaluation Standards

ERIC Educational Resources Information Center

Stufflebeam, Daniel L.

2004-01-01

The past few years have seen efforts in several countries and a wide range of disciplines to adopt and apply existing professional standards for guiding and judging evaluation services and/or develop new standards. Some of the efforts have drawn from the work and products of the North American Joint Committee on Standards for Educational…

Development of assembly and joint concepts for erectable space structures

NASA Technical Reports Server (NTRS)

Jacquemin, G. G.; Bluck, R. M.; Grotbeck, G. H.; Johnson, R. R.

1980-01-01

The technology associated with the on-orbit assembly of tetrahedral truss platforms erected of graphite epoxy tapered columns is examined. Associated with the assembly process is the design and fabrication of nine member node joints. Two such joints demonstrating somewhat different technology were designed and fabricated. Two methods of automatic assembly using the node designs were investigated, and the time of assembly of tetrahedral truss structures up to 1 square km in size was estimated. The effect of column and node joint packaging on the Space Shuttle cargo bay is examined. A brief discussion is included of operating cost considerations and the selection of energy sources. Consideration was given to the design assembly machines from 5 m to 20 m. The smaller machines, mounted on the Space Shuttle, are deployable and restowable. They provide a means of demonstrating the capabilities of the concept and of erecting small specialized platforms on relatively short notice.

Joint Development of a Fourth Generation Single Crystal Superalloy

NASA Technical Reports Server (NTRS)

Walston, S.; Cetel, A.; MacKay, R.; OHara, K.; Duhl, D.; Dreshfield, R.

2004-01-01

A new, fourth generation, single crystal superalloy has been jointly developed by GE Aircraft Engines, Pratt & Whitney, and NASA. The focus of the effort was to develop a turbine airfoil alloy with long-term durability for use in the High Speed Civil Transport. In order to achieve adequate long-time strength improvements at moderate temperatures and retain good microstructural stability, it was necessary to make significant composition changes from 2nd and 3rd generation single crystal superalloys. These included lower chromium levels, higher cobalt and rhenium levels and the inclusion of a new alloying element, ruthenium. It was found that higher Co levels were beneficial to reducing both TCP precipitation and SRZ formation. Ruthenium caused the refractory elements to partition more strongly to the ' phase, which resulted in better overall alloy stability. The final alloy, EPM 102, had significant creep rupture and fatigue improvements over the baseline production alloys and had acceptable microstructural stability. The alloy is currently being engine tested and evaluated for advanced engine applications.

Infant joint attention, neural networks and social cognition.

PubMed

Mundy, Peter; Jarrold, William

2010-01-01

Neural network models of attention can provide a unifying approach to the study of human cognitive and emotional development (Posner & Rothbart, 2007). In this paper we argue that a neural network approach to the infant development of joint attention can inform our understanding of the nature of human social learning, symbolic thought process and social cognition. At its most basic, joint attention involves the capacity to coordinate one's own visual attention with that of another person. We propose that joint attention development involves increments in the capacity to engage in simultaneous or parallel processing of information about one's own attention and the attention of other people. Infant practice with joint attention is both a consequence and an organizer of the development of a distributed and integrated brain network involving frontal and parietal cortical systems. This executive distributed network first serves to regulate the capacity of infants to respond to and direct the overt behavior of other people in order to share experience with others through the social coordination of visual attention. In this paper we describe this parallel and distributed neural network model of joint attention development and discuss two hypotheses that stem from this model. One is that activation of this distributed network during coordinated attention enhances the depth of information processing and encoding beginning in the first year of life. We also propose that with development, joint attention becomes internalized as the capacity to socially coordinate mental attention to internal representations. As this occurs the executive joint attention network makes vital contributions to the development of human symbolic thinking and social cognition. Copyright © 2010 Elsevier Ltd. All rights reserved.

Infant Joint Attention, Neural Networks and Social Cognition

PubMed Central

Mundy, Peter; Jarrold, William

2010-01-01

Neural network models of attention can provide a unifying approach to the study of human cognitive and emotional development (Posner & Rothbart, 2007). This paper we argue that a neural networks approach to the infant development of joint attention can inform our understanding of the nature of human social learning, symbolic thought process and social cognition. At its most basic, joint attention involves the capacity to coordinate one’s own visual attention with that of another person. We propose that joint attention development involves increments in the capacity to engage in simultaneous or parallel processing of information about one’s own attention and the attention of other people. Infant practice with joint attention is both a consequence and organizer of the development of a distributed and integrated brain network involving frontal and parietal cortical systems. This executive distributed network first serves to regulate the capacity of infants to respond to and direct the overt behavior of other people in order to share experience with others through the social coordination of visual attention. In this paper we describe this parallel and distributed neural network model of joint attention development and discuss two hypotheses that stem from this model. One is that activation of this distributed network during coordinated attention enhances to depth of information processing and encoding beginning in the first year of life. We also propose that with development joint attention becomes internalized as the capacity to socially coordinate mental attention to internal representations. As this occurs the executive joint attention network makes vital contributions to the development of human symbolic thinking and social cognition. PMID:20884172

24 CFR 570.411 - Joint Community Development Program.

Code of Federal Regulations, 2013 CFR

2013-04-01

... awarded to institutions of higher education or to States and local governments applying jointly with institutions of higher education. Institutions of higher education must demonstrate the capacity to carry out... activities under title I means recent satisfactory activity by the institution of higher education's staff...

24 CFR 570.411 - Joint Community Development Program.

Code of Federal Regulations, 2014 CFR

2014-04-01

... awarded to institutions of higher education or to States and local governments applying jointly with institutions of higher education. Institutions of higher education must demonstrate the capacity to carry out... activities under title I means recent satisfactory activity by the institution of higher education's staff...

24 CFR 570.411 - Joint Community Development Program.

Code of Federal Regulations, 2012 CFR

2012-04-01

... awarded to institutions of higher education or to States and local governments applying jointly with institutions of higher education. Institutions of higher education must demonstrate the capacity to carry out... activities under title I means recent satisfactory activity by the institution of higher education's staff...

Space Station alpha joint bearing

NASA Technical Reports Server (NTRS)

Everman, Michael R.; Jones, P. Alan; Spencer, Porter A.

1987-01-01

Perhaps the most critical structural system aboard the Space Station is the Solar Alpha Rotary Joint which helps align the power generation system with the sun. The joint must provide structural support and controlled rotation to the outboard transverse booms as well as power and data transfer across the joint. The Solar Alpha Rotary Joint is composed of two transition sections and an integral, large diameter bearing. Alpha joint bearing design presents a particularly interesting problem because of its large size and need for high reliability, stiffness, and on orbit maintability. The discrete roller bearing developed is a novel refinement to cam follower technology. It offers thermal compensation and ease of on-orbit maintenance that are not found in conventional rolling element bearings. How the bearing design evolved is summarized. Driving requirements are reviewed, alternative concepts assessed, and the selected design is described.

Wormhole Formation in RSRM Nozzle Joint Backfill

NASA Technical Reports Server (NTRS)

Stevens, J.

2000-01-01

The RSRM nozzle uses a barrier of RTV rubber upstream of the nozzle O-ring seals. Post flight inspection of the RSRM nozzle continues to reveal occurrence of "wormholes" into the RTV backfill. The term "wormholes", sometimes called "gas paths", indicates a gas flow path not caused by pre-existing voids, but by a little-understood internal failure mode of the material during motor operation. Fundamental understanding of the mechanics of the RSRM nozzle joints during motor operation, nonlinear viscoelastic characterization of the RTV backfill material, identification of the conditions that predispose the RTV to form wormholes, and screening of candidate replacement materials is being pursued by a joint effort between Thiokol Propulsion, NASA, and the Army Propulsion & Structures Directorate at Redstone Arsenal. The performance of the RTV backfill in the joint is controlled by the joint environment. Joint movement, which applies a tension and shear load on the material, coupled with the introduction of high pressure gas in combination create an environment that exceeds the capability of the material to withstand the wormhole effect. Little data exists to evaluate why the material fails under the modeled joint conditions, so an effort to characterize and evaluate the material under these conditions was undertaken. Viscoelastic property data from characterization testing will anchor structural analysis models. Data over a range of temperatures, environmental pressures, and strain rates was used to develop a nonlinear viscoelastic model to predict material performance, develop criteria for replacement materials, and quantify material properties influencing wormhole growth. Three joint simulation analogs were developed to analyze and validate joint thermal barrier (backfill) material performance. Two exploratory tests focus on detection of wormhole failure under specific motor operating conditions. A "validation" test system provides data to "validate" computer models and

Development of Mathematic Model of Cold Welding at Drawing-up the Flange Joint of Pneumohydraulic Systems

NASA Astrophysics Data System (ADS)

Boyko, Y. S.

2002-01-01

Provision of high airtightness of joints of pipe- lines of pneumohydraulic systems (PHS) operating under high pressure, is an important task for designing and operation of launch vehicles. In the process of assembly and tests of PHS of launch vehicles, it was found that detachable flange joints do not lose their airtightness after removal of fastening elements, even in conditions of standard loads. The task of this work is in studying a phenomenon connected with initiation of the observed effect of adhesion and also stresses in the zone of contact at drawing- up the flange detachable joints with a plastic gasket. Investigations have shown that density of the joint is kept due to cold welding, as the created conditions are helpful for that process. As a result of the investigations performed, we have developed a mathematic model which is based on application of the theory of metal bonds; that theory explains the essence of the effect observed. Basic factors which provide optimum mode of cold welding, are effort which can cause microplastic deformation and form maximum contact, and also quality of processing the material of the surfaces joined. Strength of all- metal joint depends on factual area of contact. So, surface processing quality defines a configuration of microbulges which come into contact not simultaneously, and their stressed state is different, and it influences the character of dependence of the contact area on loading. Results of calculations by the mathematic model are expressed by dependencies of factual area of contact and a single diameter of the contact spot on the load applied which compresses the materials with various physical properties, and on the surface processing quality. The mathematic model allows to explain the common character of the cold welding process in detachable flange joints with the plastic gasket, to determine the nature and the character of acting forces, to define kinetics and the mechanism of formation of cold welding of

Ablating spinal NK1-bearing neurons eliminates the development of pain & reduces spinal neuronal hyperexcitability & inflammation from mechanical joint injury in the rat

PubMed Central

Weisshaar, Christine L.; Winkelstein, Beth A.

2014-01-01

The facet joint is a common source of pain especially from mechanical injury. Although chronic pain is associated with altered spinal glial and neuronal responses, the contribution of specific spinal cells to joint pain are not understood. This study used the neurotoxin [Sar9,Met(O2)11]-substance P-saporin (SSP-SAP) to selectively eliminate spinal cells expressing neurokinin-1 receptor (NK1R) in a rat model of painful facet joint injury to determine the role of those spinal neurons in pain from facet injury. Following spinal administration of SSP-SAP or its control (blank-SAP), a cervical facet injury was imposed and behavioral sensitivity assessed. Spinal extracellular recordings were made on day 7 to classify neurons and quantify evoked firing. Spinal glial activation and IL1α expression also were evaluated. SSP-SAP prevented the development of mechanical hyperalgesia that is induced by joint injury and reduced NK1R expression and mechanically-evoked neuronal firing in the dorsal horn. SSP-SAP also prevented a shift toward wide dynamic range neurons that is seen after injury. Spinal astrocytic activation and IL1α expression were reduced to sham levels with SSP-SAP treatment. These results suggest that spinal NK1R-bearing cells are critical in initiating spinal nociception and inflammation associated with a painful mechanical joint injury. Perspective Results demonstrate that cells expressing NK1R in the spinal cord are critical for the development of joint pain and spinal neuroplasticity and inflammation after trauma to the joint. These findings have utility for understanding mechanisms of joint pain and developing potential targets to treat pain. PMID:24389017

Joint Airspace Control, Doctrine Update 10-06

DTIC Science & Technology

2010-05-20

Doctrine Update 10-06 Joint Publication 3-52, Joint Airspace Control JP 3-52 provides joint doctrine for airspace control across the full range...identification, combined operations, and unmanned aerial vehicle If you want read the complete new doctrine document, dated 20 May 2010, click here: JP 3-52...Joint Airspace Control. For more information, visit the LeMay Center for Doctrine Development and Education, call us at DSN 493-7442, or e-mail

Student perspectives on the development and evaluation of a joint international education to promote employability in Europe.

PubMed

Craig, Claire; Piškur, Barbara

2012-01-01

This article presents a student evaluation of a joint international education developed as part of a European project which sought to equip health care practitioners with the skills to support employability of individuals furthest removed from the labour market, disadvantaged on account of age, gender, migration or ethnicity. Thirty eight students out of the forty one students that participated in the pilot of four modules (NL, UK, SE, DE) returned completed digital questionnaires (92.6% response rate). The study is descriptive by nature. A questionnaire was used to collect the data from students. Additionally students attending the module in the UK also took part in a series of qualitative interviews which sought to explore their experiences in more detail. These were recorded, transcribed and analyzed. Students reported that joint education facilitates competence development. The competencies they identified (Information Communications Technology) were recognised as being key to enhancing employability of disadvantaged groups. The joint international education exemplified by EEE4all offers one model of how to build a responsive international curriculum to ensure that the workforce of the future is well placed to meet the needs of this changing world.

Towards a Socio-Cultural Framework for the Analysis of Joint Student-Teacher Development over Technology-Based Mathematics Lessons

ERIC Educational Resources Information Center

Monaghan, John

2013-01-01

This paper offers a framework, an extension of Valsiner's "zone theory", for the analysis of joint student-teacher development over a series of technology-based mathematics lessons. The framework is suitable for developing research studies over a moderately long period of time and considers interrelated student-teacher development as…

Biotribology of Cartilage Wear in Knee and Hip Joints Review of Recent Developments

NASA Astrophysics Data System (ADS)

Gulsen, Akdogan; Merve, Goncu; Meltem, Parlak

2018-01-01

Nowadays, the problem of wear in the knee and hip joints is an important issue that concerns many people and still requires new solutions. In recent years, researchers dealing with knee and hip articular cartilage erosion continue to investigate the subject in terms of biotribology. In this study, recent developments and studies in this relevant area are been examined. By using the basic principles of tribology, useful new methods that can be used in the field of biotribology can be produced. Artificial joints designed using various materials such as metals, ceramics, polymers and composites are still being studied. New studies in this area will affect the development of implant technology. Different alloys or composites are currently being tested for new implant designs. Moving implants with a risk of wear are tested in laboratory conditions in simulator devices before they are used in the human body. Major topics such as nanotechnology, tissue engineering, orthopedics, tribology, biotribology, lubrication, organ transplantation and artificial organs, which are still important today, will be useful in the search for finding suitable solutions in the future in biotribological studies. This review article aims to provide an overview of in-vitro studies at the theoretical and laboratory conditions that must be performed prior to clinical investigation.

Osteoprotegerin reduces the development of pain behaviour and joint pathology in a model of osteoarthritis

PubMed Central

Sagar, Devi Rani; Ashraf, Sadaf; Xu, Luting; Burston, James J; Menhinick, Matthew R; Poulter, Caroline L; Bennett, Andrew J; Walsh, David A; Chapman, Victoria

2014-01-01

Background Increased subchondral bone turnover may contribute to pain in osteoarthritis (OA). Objectives To investigate the analgesic potential of a modified version of osteoprotegerin (osteoprotegerin-Fc (OPG-Fc)) in the monosodium iodoacetate (MIA) model of OA pain. Methods Male Sprague Dawley rats (140–260 g) were treated with either OPG-Fc (3 mg/kg, subcutaneously) or vehicle (phosphate-buffered saline) between days 1 and 27 (pre-emptive treatment) or days 21 and 27 (therapeutic treatment) after an intra-articular injection of MIA (1 mg/50 µl) or saline. A separate cohort of rats received the bisphosphonate zoledronate (100 µg/kg, subcutaneously) between days 1 and 25 post-MIA injection. Incapacitance testing and von Frey (1–15 g) hind paw withdrawal thresholds were used to assess pain behaviour. At the end of the study, rats were killed and the knee joints and spinal cord removed for analysis. Immunohistochemical studies using Iba-1 and GFAP quantified levels of activation of spinal microglia and astrocytes, respectively. Joint sections were stained with haematoxylin and eosin or Safranin-O fast green and scored for matrix proteoglycan and overall joint morphology. The numbers of tartrate-resistant acid phosphatase-positive osteoclasts were quantified. N=10 rats/group. Results Pre-emptive treatment with OPG-Fc significantly attenuated the development of MIA-induced changes in weightbearing, but not allodynia. OPG-Fc decreased osteoclast number, inhibited the formation of osteophytes and improved structural pathology within the joint similarly to the decrease seen after pretreatment with the bisphosphonate, zoledronate. Therapeutic treatment with OPG-Fc decreased pain behaviour, but did not improve pathology in rats with established joint damage. Conclusions Our data suggest that early targeting of osteoclasts may reduce pain associated with OA. PMID:23723320

First Phase Development of Korea-Japan Joint VLBI Correlator and Its Current Progress

NASA Technical Reports Server (NTRS)

Oh, Se-Jin; Roh, Duk-Gyoo; Yeom, Jae-Hwan; Kobayashi, Hideyuki; Kawaguchi, Noriyuki

2010-01-01

The first phase of the Korea-Japan Joint VLBI Correlator (KJJVC) development has been completed and installed to correlate the observed data from KVN (Korean VLBI Network) and VERA (VLBI Exploration of Radio Astrometry) in October 2009. KJJVC is able to process 16 stations, a maximum of 8 Gbps/station, and 8,192 output channels for VLBI data. The system configuration, the experimental results, and future plans are introduced in this paper.

Synovial joint formation requires local Ext1 expression and heparan sulfate production in developing mouse embryo limbs and spine.

PubMed

Mundy, Christina; Yasuda, Tadashi; Kinumatsu, Takashi; Yamaguchi, Yu; Iwamoto, Masahiro; Enomoto-Iwamoto, Motomi; Koyama, Eiki; Pacifici, Maurizio

2011-03-01

Heparan sulfate proteoglycans (HSPGs) regulate a number of major developmental processes, but their roles in synovial joint formation remain unknown. Here we created conditional mouse embryo mutants lacking Ext1 in developing joints by mating Ext1(f/f) and Gdf5-Cre mice. Ext1 encodes a subunit of the Ext1/Ext2 Golgi-associated protein complex responsible for heparan sulfate (HS) synthesis. The proximal limb joints did form in the Gdf5-Cre;Ext1(f/f) mutants, but contained an uneven articulating superficial zone that expressed very low lubricin levels. The underlying cartilaginous epiphysis was deranged as well and displayed random patterns of cell proliferation and matrillin-1 and collagen IIA expression, indicative of an aberrant phenotypic definition of the epiphysis itself. Digit joints were even more affected, lacked a distinct mesenchymal interzone and were often fused likely as a result of local abnormal BMP and hedgehog activity and signaling. Interestingly, overall growth and lengthening of long bones were also delayed in the mutants. To test whether Ext1 function is needed for joint formation at other sites, we examined the spine. Indeed, entire intervertebral discs, normally composed by nucleus pulposus surrounded by the annulus fibrosus, were often missing in Gdf5-Cre;Ext1(f/f) mice. When disc remnants were present, they displayed aberrant organization and defective joint marker expression. Similar intervertebral joint defects and fusions occurred in Col2-Cre;β-catenin(f/f) mutants. The study provides novel evidence that local Ext1 expression and HS production are needed to maintain the phenotype and function of joint-forming cells and coordinate local signaling by BMP, hedgehog and Wnt/β-catenin pathways. The data indicate also that defects in joint formation reverberate on, and delay, overall long bone growth. Copyright © 2011 Elsevier Inc. All rights reserved.

Joint Chiefs of Staff > About > The Joint Staff > Senior Enlisted Advisor

Science.gov Websites

, Vice Chairman, and Deputies to the CJCS on standards, professional development, advancement, pay . * Helps develop and enhance Enlisted Joint Professional Military Education (EJPME) in conjunction with the Enlisted Professional Military Education Program (EPMEP) CJCSI 1805.01 series, and serves on the Keystone

Evaluation of tantalum 316 stainless steel transition joints

NASA Technical Reports Server (NTRS)

Stoner, D. R.

1972-01-01

Tubular transition joints providing a metallurgically bonded connection between tantalum and 316 stainless steel pipe sections were comparatively evaluated for durability under thermal cycling conditions approximating the operation of a SNAP-8 mercury boiler. Both coextruded and vacuum brazed transition joints of 50mm (2 inch) diameter were tested by thermal cycling 100 times between 730 C and 120 C(1350 F and 250 F) in a high vacuum environment. The twelve evaluated transition joints survived the full test sequence without developing leaks, although liquid penetrant bond line indications eventually developed in all specimens. The brazed transition joints exhibited the best dimensional stability and bond line durability.

Bolted joints in graphite-epoxy composites

NASA Technical Reports Server (NTRS)

Hart-Smith, L. J.

1976-01-01

All-graphite/epoxy laminates and hybrid graphite-glass/epoxy laminates were tested. The tests encompassed a range of geometries for each laminate pattern to cover the three basic failure modes - net section tension failure through the bolt hole, bearing and shearout. Static tensile and compressive loads were applied. A constant bolt diameter of 6.35 mm (0.25 in.) was used in the tests. The interaction of stress concentrations associated with multi-row bolted joints was investigated by testing single- and double-row bolted joints and open-hole specimens in tension. For tension loading, linear interaction was found to exist between the bearing stress reacted at a given bolt hole and the remaining tension stress running by that hole to be reacted elsewhere. The interaction under compressive loading was found to be non-linear. Comparative tests were run using single-lap bolted joints and double-lap joints with pin connection. Both of these joint types exhibited lower strengths than were demonstrated by the corresponding double-lap joints. The analysis methods developed here for single bolt joints are shown to be capable of predicting the behavior of multi-row joints.

PRN 2011-1: Residential Exposure Joint Venture

EPA Pesticide Factsheets

This PR Notice is to advise registrants of an industry-wide joint venture, titled the Residential Exposure Joint Venture (REJV), which has developed a national survey regarding residential consumer use/usage data for pesticides.

Robotic joint experiments under ultravacuum

NASA Technical Reports Server (NTRS)

Borrien, A.; Petitjean, L.

1988-01-01

First, various aspects of a robotic joint development program, including gearbox technology, electromechanical components, lubrication, and test results, are discussed. Secondly, a test prototype of the joint allowing simulation of robotic arm dynamic effects is presented. This prototype is tested under vacuum with different types of motors and sensors to characterize the functional parameters: angular position error, mechanical backlash, gearbox efficiency, and lifetime.

Adhesive-bonded scarf and stepped-lap joints

NASA Technical Reports Server (NTRS)

Hart-Smith, L. J.

1973-01-01

Continuum mechanics solutions are derived for the static load-carrying capacity of scarf and stepped-lap adhesive-bonded joints. The analyses account for adhesive plasticity and adherend stiffness imbalance and thermal mismatch. The scarf joint solutions include a simple algebraic formula which serves as a close lower bound, within a small fraction of a per cent of the true answer for most practical geometries and materials. Digital computer programs were developed and, for the stepped-lap joints, the critical adherend and adhesive stresses are computed for each step. The scarf joint solutions exhibit grossly different behavior from that for double-lap joints for long overlaps inasmuch as that the potential bond shear strength continues to increase with indefinitely long overlaps on the scarf joints. The stepped-lap joint solutions exhibit some characteristics of both the scarf and double-lap joints. The stepped-lap computer program handles arbitrary (different) step lengths and thickness and the solutions obtained have clarified potentially weak design details and the remedies. The program has been used effectively to optimize the joint proportions.

Evaluation of pipe-type cable joint restraint systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Silver, D.A.; Seman, G.W.

1990-03-01

the purpose of this project was to evaluate two systems for restraining the movement of 345kV high-pressure oil-filled (HPOF) cable joints during load cycling. Problems with joints and adjacent cables due to thermomechanical bending (TMB) experienced by the Consolidated Edison Company of New York and Public Service Electric Gas Company of New Jersey are reviewed. Some approaches to reducing or preventing TMB induced damage to HPOF pipe type cable joints are discussed. The design and operation of a special test apparatus for simulating TMB effects under laboratory conditions is described. One of the two joint restraint systems evaluated under thismore » project was developed by PSE G and employed wedging devices, which could be retrofitted into existing installations, that limited the longitudinal movement of the joints during load cycling. The other system developed by Pirelli Cable Corporation applied the restraining force to the cylindrical portion of the hand applied joint insulation by means of support spiders and steel rods attached to the reducer faces. The test results show that the PSE G restraint system can effectively limit joint longitudinal movement while causing a minimal amount of mechanical disturbance to the joint stress cones. The test results obtained with the PCC system are inconclusive and indicate that further refinement and testing are required to demonstrate the effectiveness of this promising joint restraint system.« less

Relationship of medial gastrocnemius relative fascicle excursion and ankle joint power and work performance during gait in typically developing children: A cross-sectional study.

PubMed

Martín Lorenzo, Teresa; Albi Rodríguez, Gustavo; Rocon, Eduardo; Martínez Caballero, Ignacio; Lerma Lara, Sergio

2017-07-01

Muscle fascicles lengthen in response to chronic passive stretch through in-series sarcomere addition in order to maintain an optimum sarcomere length. In turn, the muscles' force generating capacity, maximum excursion, and contraction velocity is enhanced. Thus, longer fascicles suggest a greater capacity to develop joint power and work. However, static fascicle length measurements may not be taking sarcomere length differences into account. Thus, we considered relative fascicle excursions through passive ankle dorsiflexion may better correlate with the capacity to generate joint power and work than fascicle length. Therefore, the aim of the present study was to determine if medial gastrocnemius relative fascicle excursions correlate with ankle joint power and work generation during gait in typically developing children. A sample of typically developing children (n = 10) were recruited for this study and data analysis was carried out on 20 legs. Medial gastrocnemius relative fascicle excursion from resting joint angle to maximum dorsiflexion was estimated from trigonometric relations of medial gastrocnemius pennation angle and thickness obtained from B-mode real-time ultrasonography. Furthermore, a three-dimensional motion capture system was used to obtain ankle joint work and power during the stance phase of gait. Significant correlations were found between relative fascicle excursion and peak power absorption (-) r(14) = -0.61, P = .012 accounting for 31% variability, positive work r(18) = 0.56, P = .021 accounting for 31% variability, and late stance positive work r(15) = 0.51, P = .037 accounting for 26% variability. The large unexplained variance may be attributed to mechanics of neighboring structures (e.g., soleus or Achilles tendon mechanics) and proximal joint kinetics which may also contribute to ankle joint power and work performance, and were not taken into account. Further studies are encouraged to provide greater insight

Preliminary Design and Analysis of an In-plane PRSEUS Joint

NASA Technical Reports Server (NTRS)

Lovejoy, Andrew E.; Poplawski, Steven

2013-01-01

As part of the National Aeronautics and Space Administration's (NASA's) Environmentally Responsible Aviation (ERA) program, the Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) has been designed, developed and tested. However, PRSEUS development efforts to date have only addressed joints required to transfer bending moments between PRSEUS panels. Development of in-plane joints for the PRSEUS concept is necessary to facilitate in-plane transfer of load from PRSEUS panels to an adjacent structure, such as from a wing panel into a fuselage. This paper presents preliminary design and analysis of an in-plane PRSEUS joint for connecting PRSEUS panels at the termination of the rod-stiffened stringers. Design requirements are provided, the PRSEUS blade joint concept is presented, and preliminary design changes and analyses are carried out to examine the feasibility of the proposed in-plane PRSEUS blade joint. The study conducted herein focuses mainly on the PRSEUS structure on one side of the joint. In particular, the design requirements for the rod shear stress and bolt bearing stress are examined. A PRSEUS blade joint design was developed that demonstrates the feasibility of this in-plane PRSEUS joint concept to terminate the rod-stiffened stringers. The presented design only demonstrates feasibility, therefore, some areas of refinement are presented that would lead to a more optimum and realistic design.

Development and application of biomimetic electrospun nanofibers in total joint replacement

NASA Astrophysics Data System (ADS)

Song, Wei

Failure of osseointegration (direct anchorage of an implant by bone formation at the bone-implant surface) and implant infection (such as that caused by Staphylococcus aureus, S. aureus) are the two main causes of implant failure and loosening. There is a critical need for orthopedic implants that promote rapid osseointegration and prevent bacterial colonization, particularly when placed in bone compromised by disease or physiology of the patients. A better understanding of the key factors that influence cell fate decisions at the bone-implant interface is required. Our study is to develop a class of "bone-like" nanofibers (NFs) that promote osseointegration while preventing bacterial colonization and subsequent infections. This research goal is supported by our preliminary data on the preparation of coaxial electrospun NFs composed of polycaprolactone (PCL) and polyvinyl alcohol (PVA) polymers arranged in a core-sheath shape. The PCL/PVA NFs are biocompatible and biodegradable with appropriate fiber diameter, pore size and mechanical strength, leading to enhanced cell adhesion, proliferation and differentiation of osteoblast precursor cells. The objective is to develop functionalized "bone-like" PCL/PVA NFs matrix embedded with antibiotics (doxycycline (Doxy), bactericidal and anti-osteoclastic) on prosthesis surface. Through a rat tibia implantation model, the Doxy incorporated coaxial NFs has demonstrated excellent in promoting osseointegration and bacteria inhibitory efficacy. NFs coatings significantly enhanced the bonding between implant and bone remodeling within 8 weeks. The SA-induced osteomyelitis was prevented by the sustained release of Doxy from NFs. The capability of embedding numerous bio-components including proteins, growth factors, drugs, etc. enables NFs an effective solution to overcome the current challenged issue in Total joint replacement. In summary, we proposed PCL/PVA electrospun nanofibers as promising biomaterials that can be applied on

Strength evaluation of socket joints

NASA Technical Reports Server (NTRS)

Rash, Larry C.

1994-01-01

This report documents the development of a set of equations that can be used to provide a relatively simple solution for identifying the strength of socket joints and for most cases avoid the need of more lengthy analyses. The analytical approach was verified by comparison of the contact load distributions to results obtained from a finite element analysis. The contacting surfaces for the specific joint in this analysis are in the shape of frustrums of a cone and are representative of the tapered surfaces in the socket-type joints used to join segments of model support systems for wind tunnels. The results are in the form of equations that can be used to determine the contact loads and stresses in the joint from the given geometry and externally applied loads. Equations were determined to define the bending moments and stresses along the length of the joints based on strength and materials principles. The results have also been programmed for a personal computer and a copy of the program is included.

Joint Ventures: A New Agenda for Education.

ERIC Educational Resources Information Center

Griffin, Dean

1989-01-01

The author states that vocational education can join in partnerships with industry, labor, and government to contribute to economic development. Examples of current programs are included. The "joint venture" concept is explained and ideas for forming joint ventures are shared. (CH)

The Design, Development, and Reliability Testing of a New Innovative Device to Measure Ankle Joint Dorsiflexion.

PubMed

Charles, James

2016-09-02

In clinical and research settings, ankle joint dorsiflexion needs to be reliably measured. Dorsiflexion is often measured by goniometry, but the intrarater and interrater reliability of this technique have been reported to be poor. Many devices to measure dorsiflexion have been developed for clinical and research use. An evaluation of 12 current tools showed that none met all of the desirable criteria. The purpose of this study was to design and develop a device that rates highly in all of the criteria and that can be proved to be highly reliable. While supine on a treatment table, 14 participants had a foot placed in the Charles device and ankle joint dorsiflexion measured and recorded three times with a digital inclinometer. The mean of the three readings was determined to be the ankle joint dorsiflexion. The analysis used was intraclass correlation coefficient (ICC). There was very little difference in ICC single or average measures between left and right feet, so data were pooled (N = 28). The single-measure ICC was 0.998 (95% confidence interval, 0.996-0.998). The average-measure ICC was 0.998 (95% confidence interval, 0.995-0.999). Limits of agreement for the average measure were also very good: -1.30° to 1.65°. The Charles device meets all of the desirable criteria and has many innovative features, increasing its appropriateness for clinical and research applications. It has a suitable design for measuring dorsiflexion and high intrarater and interrater reliability.

[The development of a finger joint phantom for the optical simulation of early inflammatory rheumatic changes].

PubMed

Prapavat, V; Runge, W; Mans, J; Krause, A; Beuthan, J; Müller, G

1997-11-01

In the field of rheumatology, conventional diagnostic methods permit the detection only of advanced stages of the disease, which is at odds with the current clinical demand for the early diagnosis of inflammatory rheumatic diseases. Prompted by current needs, we developed a finger joint phantom that enables the optical and geometrical simulation of an early stage of rheumatoid arthritis (RA). The results presented here form the experimental basis for an evaluation of new RA diagnostic systems based on near infrared light. The early stage of RA is characterised mainly by a vigorous proliferation of the synovial membrane and clouding of the synovial fluid. Using a double-integrating-sphere technique, the absorption and scattering coefficients (mua, mus') are experimentally determined for healthy and pathologically altered synovial fluid and capsule tissue. Using a variable mixture of Intralipid Indian ink and water as a scattering/absorption medium, the optical properties of skin, synovial fluid or capsule can be selected individually. Since the optical and geometrical properties of bone tissue remain constant in early-stage RA, a solid material is used for its simulation. Using the finger joint phantom described herein, the optical properties of joint regions can be adjusted specifically, enabling an evaluation of their effects on an optical signal--for example, during fluorography--and the investigation of these effects for diagnostically useful information. The experimental foundation for the development of a new optical system for the early diagnosis of RA has now been laid.

Clinical synovitis in a particular joint is associated with progression of erosions and joint space narrowing in that same joint, but not in patients initially treated with infliximab.

PubMed

Klarenbeek, N B; Güler-Yüksel, M; van der Heijde, D M F M; Hulsmans, H M J; Kerstens, P J S M; Molenaar, T H E; de Sonnaville, P B J; Huizinga, T W J; Dijkmans, B A C; Allaart, C F

2010-12-01

To assess the relationship between joint tenderness, swelling and joint damage progression in individual joints and to evaluate the influence of treatment on these relationships. First-year data of the Behandel Strategieën (BeSt) study were used, in which patients recently diagnosed as having rheumatoid arthritis (RA) were randomly assigned into four different treatment strategies. Baseline and 1-year x-rays of the hands and feet were assessed using the Sharp-van der Heijde score (SHS). With generalised estimating equations, 3-monthly assessments of tender and swollen joints of year 1 were related to erosion progression, joint space narrowing (JSN) progression and total SHS progression at the individual joint level (definition > 0.5 SHS units) in year 1, corrected for potential confounders and within-patient correlation for multiple joints per patient. During year 1, 59% of all 13 959 joints analysed were ever tender and 45% ever swollen, 2.1% showed erosion progression, 1.9% JSN progression and 3.6% SHS progression. Swelling and tenderness were both independently associated with erosion and JSN progression with comparable OR, although with higher OR in the hands than in the feet. Local swelling and tenderness were not associated with local damage progression in patients initially treated with infliximab. Clinical signs of synovitis are associated with erosion and JSN progression in individual joints after 1 year in RA. A disconnect between synovitis and joint damage progression was observed at joint level in patients who were treated with methotrexate and infliximab as initial treatment, confirming the disconnect between synovitis and the development of joint damage in tumour necrosis factor blockers seen at patient level.

Solder Joint Health Monitoring Testbed

NASA Technical Reports Server (NTRS)

Delaney, Michael M.; Flynn, James; Browder, Mark

2009-01-01

A method of monitoring the health of selected solder joints, called SJ-BIST, has been developed by Ridgetop Group Inc. under a Small Business Innovative Research (SBIR) contract. The primary goal of this research program is to test and validate this method in a flight environment using realistically seeded faults in selected solder joints. An additional objective is to gather environmental data for future development of physics-based and data-driven prognostics algorithms. A test board is being designed using a Xilinx FPGA. These boards will be tested both in flight and on the ground using a shaker table and an altitude chamber.

Osteoprotegerin reduces the development of pain behaviour and joint pathology in a model of osteoarthritis.

PubMed

Sagar, Devi Rani; Ashraf, Sadaf; Xu, Luting; Burston, James J; Menhinick, Matthew R; Poulter, Caroline L; Bennett, Andrew J; Walsh, David A; Chapman, Victoria

2014-08-01

Increased subchondral bone turnover may contribute to pain in osteoarthritis (OA). To investigate the analgesic potential of a modified version of osteoprotegerin (osteoprotegerin-Fc (OPG-Fc)) in the monosodium iodoacetate (MIA) model of OA pain. Male Sprague Dawley rats (140-260 g) were treated with either OPG-Fc (3 mg/kg, subcutaneously) or vehicle (phosphate-buffered saline) between days 1 and 27 (pre-emptive treatment) or days 21 and 27 (therapeutic treatment) after an intra-articular injection of MIA (1 mg/50 µl) or saline. A separate cohort of rats received the bisphosphonate zoledronate (100 µg/kg, subcutaneously) between days 1 and 25 post-MIA injection. Incapacitance testing and von Frey (1-15 g) hind paw withdrawal thresholds were used to assess pain behaviour. At the end of the study, rats were killed and the knee joints and spinal cord removed for analysis. Immunohistochemical studies using Iba-1 and GFAP quantified levels of activation of spinal microglia and astrocytes, respectively. Joint sections were stained with haematoxylin and eosin or Safranin-O fast green and scored for matrix proteoglycan and overall joint morphology. The numbers of tartrate-resistant acid phosphatase-positive osteoclasts were quantified. N=10 rats/group. Pre-emptive treatment with OPG-Fc significantly attenuated the development of MIA-induced changes in weightbearing, but not allodynia. OPG-Fc decreased osteoclast number, inhibited the formation of osteophytes and improved structural pathology within the joint similarly to the decrease seen after pretreatment with the bisphosphonate, zoledronate. Therapeutic treatment with OPG-Fc decreased pain behaviour, but did not improve pathology in rats with established joint damage. Our data suggest that early targeting of osteoclasts may reduce pain associated with OA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Spacesuit mobility joints

NASA Technical Reports Server (NTRS)

Vykukal, H. C. (Inventor)

1978-01-01

Joints for use in interconnecting adjacent segments of an hermetically sealed spacesuit which have low torques, low leakage and a high degree of reliability are described. Each of the joints is a special purpose joint characterized by substantially constant volume and low torque characteristics. Linkages which restrain the joint from longitudinal distension and a flexible, substantially impermeable diaphragm of tubular configuration spanning the distance between pivotally supported annuli are featured. The diaphragms of selected joints include rolling convolutions for balancing the joints, while various joints include wedge-shaped sections which enhance the range of motion for the joints.

The "Dual Usage Problem" in the Explanations of "Joint Attention" and Children's Socioemotional Development: A Reconceptualization

ERIC Educational Resources Information Center

Tasker, Susan L.; Schmidt, Louis A.

2008-01-01

The term "joint attention", which first gained currency in the early 1960s in studies of the development of language and symbolic thought, remains significant in the developmental literature. However, its meaning is unclear. A definitional problem exists similar to what Patterson [Patterson, M. L. (1982). "A sequential functional model of…

DEMES rotary joint: theories and applications

NASA Astrophysics Data System (ADS)

Wang, Shu; Hao, Zhaogang; Li, Mingyu; Huang, Bo; Sun, Lining; Zhao, Jianwen

2017-04-01

As a kind of dielectric elastomer actuators, dielectric elastomer minimum energy structure (DEMES) can realize large angular deformations by small voltage-induced strains, which make them an attractive candidate for use as biomimetic robotics. Considering the rotary joint is a basic and common component of many biomimetic robots, we have been fabricated rotary joint by DEMES and developed its performances in the past two years. In this paper, we have discussed the static analysis, dynamics analysis and some characteristics of the DEMES rotary joint. Based on theoretical analysis, some different applications of the DEMES rotary joint were presented, such as a flapping wing, a biomimetic fish and a two-legged walker. All of the robots are fabricated by DEMES rotary joint and can realize some basic biomimetic motions. Comparing with traditional rigid robot, the robot based on DEMES is soft and light, so it has advantage on the collision-resistant.

Shear joint capability versus bolt clearance

NASA Technical Reports Server (NTRS)

Lee, H. M.

1992-01-01

The results of a conservative analysis approach into the determination of shear joint strength capability for typical space-flight hardware as a function of the bolt-hole clearance specified in the design are presented. These joints are comprised of high-strength steel fasteners and abutments constructed of aluminum alloys familiar to the aerospace industry. A general analytical expression was first arrived at which relates bolt-hole clearance to the bolt shear load required to place all joint fasteners into a shear transferring position. Extension of this work allowed the analytical development of joint load capability as a function of the number of fasteners, shear strength of the bolt, bolt-hole clearance, and the desired factor of safety. Analysis results clearly indicate that a typical space-flight hardware joint can withstand significant loading when less than ideal bolt hole clearances are used in the design.

Nonlinear Modeling of Joint Dominated Structures

NASA Technical Reports Server (NTRS)

Chapman, J. M.

1990-01-01

The development and verification of an accurate structural model of the nonlinear joint-dominated NASA Langley Mini-Mast truss are described. The approach is to characterize the structural behavior of the Mini-Mast joints and struts using a test configuration that can directly measure the struts' overall stiffness and damping properties, incorporate this data into the structural model using the residual force technique, and then compare the predicted response with empirical data taken by NASA/LaRC during the modal survey tests of the Mini-Mast. A new testing technique, referred to as 'link' testing, was developed and used to test prototype struts of the Mini-Masts. Appreciable nonlinearities including the free-play and hysteresis were demonstrated. Since static and dynamic tests performed on the Mini-Mast also exhibited behavior consistent with joints having free-play and hysteresis, nonlinear models of the Mini-Mast were constructed and analyzed. The Residual Force Technique was used to analyze the nonlinear model of the Mini-Mast having joint free-play and hysteresis.

[Classification and Treatment of Sacroiliac Joint Dislocation].

PubMed

Tan, Zhen; Huang, Zhong; Li, Liang; Meng, Wei-Kun; Liu, Lei; Zhang, Hui; Wang, Guang-Lin; Huang, Fu-Guo

2017-09-01

To develop a renewed classification and treatment regimen for sacroiliac joint dislocation. According to the direction of dislocation of sacroiliac joint,combined iliac,sacral fractures,and fracture morphology,sacroiliac joint dislocation was classified into 4 types. Type Ⅰ (sacroiliac anterior dislocation): main fracture fragments of posterior iliac wing dislocated in front of sacroiliac joint. Type Ⅱ (sacroiliac posterior dislocation): main fracture fragments of posterior iliac wing dislocated in posterior of sacroiliac joint. Type Ⅲ (Crescent fracturedislocation of the sacroiliac joint): upward dislocation of posterior iliac wing with oblique fracture through posterior iliac wing. Type ⅢA: a large crescent fragment and dislocation comprises no more than onethird of sacroiliac joint,which is typically inferior. Type ⅢB: intermediatesize crescent fragment and dislocation comprises between one and twothirds of joint. Type ⅢC: a small crescent fragment where dislocation comprises most,but not the entire joint. Different treatment regimens were selected for different types of fractures. Treatment for type Ⅰ sacroiliac joint dislocation: anterior iliac fossa approach pry stripping reset; sacroiliac joint fixed with sacroiliac screw through percutaneous. Treatment for type Ⅱ sacroiliac joint dislocation: posterior sacroiliac joint posterior approach; sacroiliac joint fixed with sacroiliac screw under computer guidance. Treatment for type ⅢA and ⅢB sacroiliac joint dislocation: posterior sacroiliac joint approach; sacroiliac joint fixed with reconstruction plate. Treatment for type ⅢC sacroiliac joint dislocation: sacroiliac joint closed reduction; sacroiliac joint fixed with sacroiliac screw through percutaneous. Treatment for type Ⅳ sacroiliac joint dislocation: posterior approach; sacroiliac joint fixed with spinal pelvic fixation. Results of 24 to 72 months patient follow-up (mean 34.5 months): 100% survival,100% wound healing,and 100

Investigation of Super*Zip separation joint

NASA Technical Reports Server (NTRS)

Bement, Laurence J.; Schimmel, Morry L.

1988-01-01

An investigation to determine the most likely cause of two failures of five tests on 79 inch diameter Lockheed Super*Zip spacecraft separation joints being used for the development of a Shuttle/Centaur propulsion system. This joint utilizes an explosively expanded tube to fracture surrounding prenotched aluminum plates to achieve planar separation. A test method was developed and more than 300 tests firings were made to provide an understanding of severance mechanisms and the functional performance effects of system variables. An approach for defining functional margin was developed, and specific recommendations were made for improving existing and future systems.

Atypical prefrontal cortical responses to joint/non-joint attention in children with autism spectrum disorder (ASD): A functional near-infrared spectroscopy study

PubMed Central

Zhu, Huilin; Li, Jun; Fan, Yuebo; Li, Xinge; Huang, Dan; He, Sailing

2015-01-01

Autism spectrum disorder (ASD) is a neuro-developmental disorder, characterized by impairments in one’s capacity for joint attention. In this study, functional near-infrared spectroscopy (fNIRS) was applied to study the differences in activation and functional connectivity in the prefrontal cortex between children with autism spectrum disorder (ASD) and typically developing (TD) children. 21 ASD and 20 TD children were recruited to perform joint and non-joint attention tasks. Compared with TD children, children with ASD showed reduced activation and atypical functional connectivity pattern in the prefrontal cortex during joint attention. The atypical development of left prefrontal cortex might play an important role in social cognition defects of children with ASD. PMID:25798296

Joint Polar Satellite System

NASA Technical Reports Server (NTRS)

Trenkle, Timothy; Driggers, Phillip

2011-01-01

The Joint Polar Satellite System (JPSS) is a joint NOAA/NASA mission comprised of a series of polar orbiting weather and climate monitoring satellites which will fly in a sun-synchronous orbit, with a 1330 equatorial crossing time. JPSS resulted from the decision to reconstitute the National Polar-orbiting Operational Environmental Satellite System (NPOESS) into two separate programs, one to be run by the Department of Defense (DOD) and the other by NOAA. This decision was reached in early 2010, after numerous development issues caused a series of unacceptable delays in launching the NPOESS system.

Heavily loaded joints for assembling aerobrake support trusses

NASA Technical Reports Server (NTRS)

Bandel, Hannskarl; Olsson, Nils; Levintov, Boris

1990-01-01

The major emphasis was to develop erectable joints for large aerobrake support trusses. The truss joints must be able to withstand the large forces experienced by the truss during the aero-pass, as well as be easily assembled and disassembled on orbit by astronauts or robots. Other important design considerations include; strength, stiffness, and allowable error in strut length. Six mechanical joint designs, as well as a seventh joint design, where a high strength epoxy is injected to make the connection rigid, are presented.

Multiple Periprosthetic Joint Infections: Evidence for Decreasing Prevalence.

PubMed

Haverstock, John P; Somerville, Lyndsa E; Naudie, Douglas D; Howard, James L

2016-12-01

Multiple periprosthetic joint infections (MPJIs) are uncommon. We determine the prevalence of developing a second-site periprosthetic joint infection. Our institutional arthroplasty database was reviewed. Those who developed a second-site infection had a retrospective chart review to determine the pathogen, timing of infection, comorbidities, and results of treatment. Thirteen of 206 (6.3%) patients at-risk for MPJI experienced a second periprosthetic joint infection. Mode of the second infection was hematogenous in 6, all of whom were being treated for the index periprosthetic joint infection. Seven secondary infections did not relate to the index infection. Two patients were lost to follow-up, 5 continued on suppressive antibiotics, and 6 successfully cleared infection. The prevalence of MPJI has decreased compared with previous reports. Copyright © 2016 Elsevier Inc. All rights reserved.

Increased expression of damage-associated molecular patterns (DAMPs) in osteoarthritis of human knee joint compared to hip joint.

PubMed

Rosenberg, John H; Rai, Vikrant; Dilisio, Matthew F; Sekundiak, Todd D; Agrawal, Devendra K

2017-12-01

Osteoarthritis (OA) is a degenerative disease characterized by the destruction of cartilage. The greatest risk factors for the development of OA include age and obesity. Recent studies suggest the role of inflammation in the pathogenesis of OA. The two most common locations for OA to occur are in the knee and hip joints. The knee joint experiences more mechanical stress, cartilage degeneration, and inflammation than the hip joint. This could contribute to the increased incidence of OA in the knee joint. Damage-associated molecular patterns (DAMPs), including high-mobility group box-1, receptor for advanced glycation end products, and alarmins (S100A8 and S100A9), are released in the joint in response to stress-mediated chondrocyte and cartilage damage. This facilitates increased cartilage degradation and inflammation in the joint. Studies have documented the role of DAMPs in the pathogenesis of OA; however, the comparison of DAMPs and its influence on OA has not been discussed. In this study, we compared the DAMPs between OA knee and hip joints and found a significant difference in the levels of DAMPs expressed in the knee joint compared to the hip joint. The increased levels of DAMPs suggest a difference in the underlying pathogenesis of OA in the knee and the hip and highlights DAMPs as potential therapeutic targets for OA in the future.

Ultrasonic-assisted soldering of Cu/Ti joints

NASA Astrophysics Data System (ADS)

Cui, Wei; Wang, Chunyu; Li, Yuhang; Zhong, Tongtong; Yang, Jianguo; Bao, Yefeng

2018-03-01

Cu/Ti joints are expected to be used in various applications, while reliable joining method is still to be developed. It is commonly not possible to solder Ti alloys using Sn-based solder alloys because of their poor wettability. In this study, Sn-Ag-Cu soldering filler metal was used to joining TC4 titanium alloy and pure copper using ultrasonic-assisted soldering. The influence of different temperature and different ultrasonic time on the welded joint is studied and explored. Microstructure of the joints was investigated. Shear strength of the joints reached the maximum value, i.e. 38.2MPa. Relationship between the sonication parameters and the microstructure and strength of the joints was discussed. Thus, it is verified that dissimilar metal brazing of TC4 and copper is suitable for low temperature soldering.

Why is joint attention a pivotal skill in autism?

PubMed Central

Charman, Tony

2003-01-01

Joint attention abilities play a crucial role in the development of autism. Impairments in joint attention are among the earliest signs of the disorder and joint attention skills relate to outcome, both in the 'natural course' of autism and through being targeted in early intervention programmes. In the current study, concurrent and longitudinal associations between joint attention and other social communication abilities measured in a sample of infants with autism and related pervasive developmental disorders at age 20 months, and language and symptom severity at age 42 months, were examined. Extending the findings from previous studies, joint attention ability was positively associated with language gains and (lower) social and communication symptoms, and imitation ability was also positively associated with later language. Some specificity in the association between different aspects of joint attention behaviours and outcome was found: declarative, triadic gaze switching predicted language and symptom severity but imperative, dyadic eye contact behaviours did not. Further, although joint attention was associated with later social and language symptoms it was unrelated to repetitive and stereotyped symptoms, suggesting the latter may have a separate developmental trajectory. Possible deficits in psychological and neurological processes that might underlie the impaired development of joint attention in autism are discussed. PMID:12639329

[Meniscoids of the intervertebral joints].

PubMed

Kos, J; Hert, J; Sevcík, P

2002-01-01

A large amount of material was used to study the distribution, location and shape of meniscoids in intervertebral joints of the human spine, from the atlanto-occipital joint to the sacrum, in order to find out how many of intervertebral joints had mobile meniscoids. These might be regarded as possible causes of spinal blockade or other vertebrogenous complaints. The materials provided by the Department of Anatomy and Department of Forensic Medicine at the Faculty of Medicine of Charles University in Pilznen included 20 cadaverous spines from humans aged 20 to 80 years. Access to each joint was provided by dissection of the articular capsule from the lower articular processes of the vertebra situated above. In the orthograde view, all meniscoids were described in terms of shape, size, consistence and location. Their structure was ascertained by histological examination of cross sections stained with haematoxylin and eosin. Meniscoids varying in shape and size were found in all of the intervertebral joints. They were classified by their histological structure as synovial, fat and fibrous meniscoids. The first category was observed frequently, the last only rarely. A total of 29 mobile meniscoids were recorded, most of them in the lumbar spine. Most of the meniscoids present in the cervical spine were of synovial and less frequently of fat types. Meniscoids found in the thoracic spine were poorly developed synovial ones and those present in the lumbar spine were of all types and were also largest in size. The most conspicuous meniscoids were seen in the spines that showed degenerative changes in intervertebral joints. Large fat pads were found in atlanto-occipital and atlanto-axial joints. Mobile meniscoids, most of them present in the lumbar spine (6.4% of all joints.), were connected with the capsule by a thin pedicle and it was possible to move them over a half of the articular surface. Some inter-individual changes were also found; in some spines, the most

Nikolaus Rüdinger (1832-1896), His Description of Joint Innervation in 1857, and the History of Surgical Joint Denervation.

PubMed

Gohritz, Andreas; Kaiser, Erich; Guggenheim, Merlin; Dellon, Arnold Lee

2018-01-01

 Selective joint denervation has become a reliable palliative treatment, especially for painful joints in the upper and lower extremity.  This article highlights the life and work of Nikolaus Rüdinger (1832-1896) who first described joint innervation which became the basis of later techniques of surgical joint denervation. The historical evolution of this method is outlined.  Rüdinger made a unique career from apprentice barber to military surgeon and anatomy professor in Munich, Germany. His first description of articular innervation of temporomandibular, shoulder, elbow, wrist, finger, sacroiliac, hip, knee, ankle, foot, and toe joints in 1857 stimulated the subsequent history of surgical joint denervation. Comparing his investigations with modern joint denervation methods, developed by pioneers like Albrecht Wilhelm or A. Lee Dellon, shows his great exactitude and anatomical correspondence despite different current terminology. Clinical series of modern surgical joint denervations reveal success rates of up to 80% with reliable long-term results.  The history of joint denervation with Rüdinger as its important protagonist offers inspiring insights into the evolution of surgical techniques and exemplifies the value of descriptive functional anatomy, even if surgical application may not have been realized until a century later. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Joint attention in parent-child dyads involving children with selective mutism: a comparison between anxious and typically developing children.

PubMed

Nowakowski, Matilda E; Tasker, Susan L; Cunningham, Charles E; McHolm, Angela E; Edison, Shannon; Pierre, Jeff St; Boyle, Michael H; Schmidt, Louis A

2011-02-01

Although joint attention processes are known to play an important role in adaptive social behavior in typical development, we know little about these processes in clinical child populations. We compared early school age children with selective mutism (SM; n = 19) versus mixed anxiety (MA; n = 18) and community controls (CC; n = 26) on joint attention measures coded from direct observations with their parent during an unstructured free play task and two structured tasks. As predicted, the SM dyads established significantly fewer episodes of joint attention through parental initiation acts than the MA and CC dyads during the structured tasks. Findings suggest that children with SM may withdraw from their parents during stressful situations, thus missing out on opportunities for learning other coping skills. We discuss the implications of the present findings for understanding the maintenance and treatment of SM.

Regeneration of limb joints in the axolotl (Ambystoma mexicanum).

PubMed

Lee, Jangwoo; Gardiner, David M

2012-01-01

In spite of numerous investigations of regenerating salamander limbs, little attention has been paid to the details of how joints are reformed. An understanding of the process and mechanisms of joint regeneration in this model system for tetrapod limb regeneration would provide insights into developing novel therapies for inducing joint regeneration in humans. To this end, we have used the axolotl (Mexican Salamander) model of limb regeneration to describe the morphology and the expression patterns of marker genes during joint regeneration in response to limb amputation. These data are consistent with the hypothesis that the mechanisms of joint formation whether it be development or regeneration are conserved. We also have determined that defects in the epiphyseal region of both forelimbs and hind limbs in the axolotl are regenerated only when the defect is small. As is the case with defects in the diaphysis, there is a critical size above which the endogenous regenerative response is not sufficient to regenerate the joint. This non-regenerative response in an animal that has the ability to regenerate perfectly provides the opportunity to screen for the signaling pathways to induce regeneration of articular cartilage and joints.

Regeneration of Limb Joints in the Axolotl (Ambystoma mexicanum)

PubMed Central

Lee, Jangwoo; Gardiner, David M.

2012-01-01

In spite of numerous investigations of regenerating salamander limbs, little attention has been paid to the details of how joints are reformed. An understanding of the process and mechanisms of joint regeneration in this model system for tetrapod limb regeneration would provide insights into developing novel therapies for inducing joint regeneration in humans. To this end, we have used the axolotl (Mexican Salamander) model of limb regeneration to describe the morphology and the expression patterns of marker genes during joint regeneration in response to limb amputation. These data are consistent with the hypothesis that the mechanisms of joint formation whether it be development or regeneration are conserved. We also have determined that defects in the epiphyseal region of both forelimbs and hind limbs in the axolotl are regenerated only when the defect is small. As is the case with defects in the diaphysis, there is a critical size above which the endogenous regenerative response is not sufficient to regenerate the joint. This non-regenerative response in an animal that has the ability to regenerate perfectly provides the opportunity to screen for the signaling pathways to induce regeneration of articular cartilage and joints. PMID:23185640

University Research and Development Activities: The Federal Income Tax Consequences of Research Contracts, Research Subsidiaries and Joint Ventures.

ERIC Educational Resources Information Center

Kertz, Consuelo Lauda; Hasson, James K., Jr.

1986-01-01

Features of the federal income tax law applying to income received from commercially funded university-based scientific research and development activities are discussed, including: industry-sponsored research contracts, separately incorporated entities, partnerships and joint ventures, subsidiaries and unrelated income consequences of…

Joint-venture proposals strengthen hospital-physician relationship.

PubMed

Rovinsky, M

2000-12-01

By proposing the joint-venture development of an ambulatory surgery center and medical office space with a group practice, one hospital succeeded in enhancing its relationship with the practice and paved the way for future collaboration. Although the hospital's proposal to jointly develop an ambulatory surgery center was not accepted, the hospital was able to dissuade the group practice from developing a competing ambulatory surgery facility while increasing the group's trust in and loyalty to the hospital. As a result, the hospital potentially will benefit from increased inpatient admissions.

The development and validation of a custom built device for assessing frontal knee joint laxity.

PubMed

Ismail, Shiek Abdullah; Simic, Milena; Clarke, Jillian L; Lopes, Thiago Jambo Alves; Pappas, Evangelos

2017-12-01

This study reports the development and validation of a quantitative technique of assessing frontal knee joint laxity through a custom built device named KLICP. The objectives of this study were to determine: (i) the intra- and inter-rater reliability and (ii) the validity of the device when compared to real time ultrasound. Twenty-five participants had their frontal knee joint laxity assessed by the KLICP, by manual varus/valgus tests and by ultrasound. Two raters independently assessed laxity manually by three repeated measurements, repeated at least 48h later. Results were validated by comparing them to the medial and lateral joint space opening measured by the ultrasound. Intraclass correlation coefficients and standard error of measurement reliability were calculated. Pearson's correlation coefficients were calculated to determine the correlation between the KLICP and the joint space. Intra-rater reliability (intra-session) for each rater was good on both sessions (0.91-0.98), intra-rater reliability (inter-sessions) was moderate to good (0.62-0.87), and inter-rater reliability (intra-session) was good (0.75-0.80). There is low agreement for intra-rater (inter-session) and for inter-rater (intra-session) reliability. The KLICP measurement has a significant positive fair to moderate correlation to the ultrasound measurement at the left (r: 0.61, p: 0.01) and right (r: 0.48, p: 0.02) knee in the valgus direction and at the left (r: 0.51, p: 0.01) and right (r: 0.39, p: 0.05) knee in the varus direction. There is low agreement between the KLICP and the RTU. Reliability and agreement was good only when measured for intra-rater, within session. Copyright © 2017 Elsevier B.V. All rights reserved.

Design and development of an intelligent nursing bed - a pilot project of "joint assignment".

PubMed

Jiehui Jiang; Tingwei Liu; Yuting Zhang; Yu Song; Mi Zhou; Xiaosong Zheng; Zhuangzhi Yan

2017-07-01

The "joint assignment" is a creative bachelor education project for Biomedical Engineering (BME) in Shanghai University (SHU), China. The objective of this project is to improve students' capabilities in design thinking and teamwork through practices in the process of the design and development of complex medical product. As the first step, a pilot project "design and development of intelligent nursing bed" was set up in May 2015. This paper describes details of how project organization and management, various teaching methods and scientific evaluation approaches were achieved in this pilot project. For example, a method containing one main line and four branches is taken to manage the project and "prototyping model" was used as the main research approach. As a result a multi-win situation was achieved. The results showed, firstly, 62 bachelor students including 16 BME students were well trained. They improved themselves in use of practical tools, communication skills and scientific writing; Secondly, commercial companies received a nice product design on intelligent nursing bed, and have been working on industrializing it; Thirdly, the university and associated schools obtained an excellent practical education experience to supplement traditional class education; Fourthly and most importantly, requirements from end-users will be met. The results also showed that the "joint assignment" task could become a significant component in BME bachelor education.

Joint effects of child temperament and maternal sensitivity on the development of childhood obesity.

PubMed

Wu, Tiejian; Dixon, Wallace E; Dalton, William T; Tudiver, Fred; Liu, Xuefeng

2011-05-01

The interplay between child characteristics and parenting is increasingly implicated as crucial to child health outcomes. This study assessed the joint effects of children's temperamental characteristics and maternal sensitivity on children's weight status. Data from the National Institute of Child Health and Human Development's Study of Early Child Care and Youth Development were utilized. Infant temperament, assessed at child's age of 6 months by maternal report, was categorized into three types: easy, average, and difficult. Maternal sensitivity, assessed at child's age of 6 months by observing maternal behaviors during mother-child semi-structured interaction, was categorized into two groups: sensitive and insensitive. Children's height and weight were measured longitudinally from age 2 years to Grade 6, and body mass index (BMI) was calculated. BMI percentile was obtained based on the Centers for Disease Control and Prevention's BMI charts. Children, who had a BMI ≥ the 85th percentile, were defined as overweight-or-obese. Generalized estimating equations were used to analyze the data. The proportions of children overweight-or-obese increased with age, 15.58% at 2 years old to 34.34% by Grade 6. The joint effects of children's temperament and maternal sensitivity on a child's body mass status depended on the child's age. For instance, children with difficult temperament and insensitive mothers had significantly higher risks for being overweight-or-obese during the school age phase but not during early childhood. Specific combinations of child temperament and maternal sensitivity were associated with the development of obesity during childhood. Findings may hold implications for childhood obesity prevention/intervention programs targeting parents.

Experiential learning implementation based on joint responsibility in women's cooperative development (Case study on Farmer Women Cooperative, Sumedang, West Java)

NASA Astrophysics Data System (ADS)

Suseno, Gijanto Purbo; Nataliningsih

2017-09-01

Cooperative extension is one form of non-formal education. The follow up of cooperative extension is a coaching that aims to cooperative boards and members apply the knowledge and skills acquired during extension. Learning from the experience (experience learning) of others combined with the concept of joint responsibility is expected to develop the participation of cooperative members as indicated by the repayment of loans on time. The research was conducted at Sumedang Farmer Women Cooperative of West Java with the stages of cooperative extension and coaching for 6 months so it can be evaluated its impact. The results showed that from 30 extension participants who stated willingness to be a member of joint responsibility group as many as 15 people (50%), which then divided into 3 groups of mutual responsibility with member of each group is 5 people. The result of impact evaluation showed the development of group dynamics of the joint liability shown by 9 people (60%) developing business, 3 people (20%) business stagnant and 3 (20%) less profitable business. Implementation of experiental learning based on the concept of mutual responsibility encourages the improvement of entrepreneurship and cooperative skills and the ability of members to pay loan installments on cooperatives in a timely manner.

77 FR 38088 - Development of the Joint Strategic Plan on Intellectual Property Enforcement; Request of the U.S...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-26

... OFFICE OF MANAGEMENT AND BUDGET Development of the Joint Strategic Plan on Intellectual Property Enforcement; Request of the U.S. Intellectual Property Enforcement Coordinator for Public Comments AGENCY: Office of the U.S. Intellectual Property Enforcement Coordinator, Executive Office of the President...

Joint attention in Down syndrome: A meta-analysis.

PubMed

Hahn, Laura J; Loveall, Susan J; Savoy, Madison T; Neumann, Allie M; Ikuta, Toshikazu

2018-07-01

Some studies have indicated that joint attention may be a relative strength in Down syndrome (DS), but other studies have not. To conduct a meta-analysis of joint attention in DS to more conclusively determine if this is a relative strength or weakness when compared to children with typical development (TD), developmental disabilities (DD), and autism spectrum disorder (ASD). Journal articles published before September 13, 2016, were identified by using the search terms "Down syndrome" and "joint attention" or "coordinating attention". Identified studies were reviewed and coded for inclusion criteria, descriptive information, and outcome variables. Eleven studies (553 participants) met inclusion criteria. Children with DS showed similar joint attention as TD children and higher joint attention than children with DD and ASD. Meta-regression revealed a significant association between age and joint attention effect sizes in the DS vs. TD contrast. Joint attention appears to not be a weakness for children with DS, but may be commensurate with developmental level. Joint attention may be a relative strength in comparison to other skills associated with the DS behavioral phenotype. Early interventions for children with DS may benefit from leveraging joint attention skills. Copyright © 2018 Elsevier Ltd. All rights reserved.

Joint Instability and Osteoarthritis

PubMed Central

Blalock, Darryl; Miller, Andrew; Tilley, Michael; Wang, Jinxi

2015-01-01

Joint instability creates a clinical and economic burden in the health care system. Injuries and disorders that directly damage the joint structure or lead to joint instability are highly associated with osteoarthritis (OA). Thus, understanding the physiology of joint stability and the mechanisms of joint instability-induced OA is of clinical significance. The first section of this review discusses the structure and function of major joint tissues, including periarticular muscles, which play a significant role in joint stability. Because the knee, ankle, and shoulder joints demonstrate a high incidence of ligament injury and joint instability, the second section summarizes the mechanisms of ligament injury-associated joint instability of these joints. The final section highlights the recent advances in the understanding of the mechanical and biological mechanisms of joint instability-induced OA. These advances may lead to new opportunities for clinical intervention in the prevention and early treatment of OA. PMID:25741184

Joint instability and osteoarthritis.

PubMed

Blalock, Darryl; Miller, Andrew; Tilley, Michael; Wang, Jinxi

2015-01-01

Joint instability creates a clinical and economic burden in the health care system. Injuries and disorders that directly damage the joint structure or lead to joint instability are highly associated with osteoarthritis (OA). Thus, understanding the physiology of joint stability and the mechanisms of joint instability-induced OA is of clinical significance. The first section of this review discusses the structure and function of major joint tissues, including periarticular muscles, which play a significant role in joint stability. Because the knee, ankle, and shoulder joints demonstrate a high incidence of ligament injury and joint instability, the second section summarizes the mechanisms of ligament injury-associated joint instability of these joints. The final section highlights the recent advances in the understanding of the mechanical and biological mechanisms of joint instability-induced OA. These advances may lead to new opportunities for clinical intervention in the prevention and early treatment of OA.

Progressive Damage Modeling of Durable Bonded Joint Technology

NASA Technical Reports Server (NTRS)

Leone, Frank A.; Davila, Carlos G.; Lin, Shih-Yung; Smeltzer, Stan; Girolamo, Donato; Ghose, Sayata; Guzman, Juan C.; McCarville, Duglas A.

2013-01-01

The development of durable bonded joint technology for assembling composite structures for launch vehicles is being pursued for the U.S. Space Launch System. The present work is related to the development and application of progressive damage modeling techniques to bonded joint technology applicable to a wide range of sandwich structures for a Heavy Lift Launch Vehicle. The joint designs studied in this work include a conventional composite splice joint and a NASA-patented Durable Redundant Joint. Both designs involve a honeycomb sandwich with carbon/epoxy facesheets joined with adhesively bonded doublers. Progressive damage modeling allows for the prediction of the initiation and evolution of damage. For structures that include multiple materials, the number of potential failure mechanisms that must be considered increases the complexity of the analyses. Potential failure mechanisms include fiber fracture, matrix cracking, delamination, core crushing, adhesive failure, and their interactions. The joints were modeled using Abaqus parametric finite element models, in which damage was modeled with user-written subroutines. Each ply was meshed discretely, and layers of cohesive elements were used to account for delaminations and to model the adhesive layers. Good correlation with experimental results was achieved both in terms of load-displacement history and predicted failure mechanisms.

Progressive Damage Analysis of Bonded Composite Joints

NASA Technical Reports Server (NTRS)

Leone, Frank A., Jr.; Girolamo, Donato; Davila, Carlos G.

2012-01-01

The present work is related to the development and application of progressive damage modeling techniques to bonded joint technology. The joint designs studied in this work include a conventional composite splice joint and a NASA-patented durable redundant joint. Both designs involve honeycomb sandwich structures with carbon/epoxy facesheets joined using adhesively bonded doublers.Progressive damage modeling allows for the prediction of the initiation and evolution of damage within a structure. For structures that include multiple material systems, such as the joint designs under consideration, the number of potential failure mechanisms that must be accounted for drastically increases the complexity of the analyses. Potential failure mechanisms include fiber fracture, intraply matrix cracking, delamination, core crushing, adhesive failure, and their interactions. The bonded joints were modeled using highly parametric, explicitly solved finite element models, with damage modeling implemented via custom user-written subroutines. Each ply was discretely meshed using three-dimensional solid elements. Layers of cohesive elements were included between each ply to account for the possibility of delaminations and were used to model the adhesive layers forming the joint. Good correlation with experimental results was achieved both in terms of load-displacement history and the predicted failure mechanism(s).

Development of a hip joint model for finite volume simulations.

PubMed

Cardiff, P; Karač, A; FitzPatrick, D; Ivanković, A

2014-01-01

This paper establishes a procedure for numerical analysis of a hip joint using the finite volume method. Patient-specific hip joint geometry is segmented directly from computed tomography and magnetic resonance imaging datasets and the resulting bone surfaces are processed into a form suitable for volume meshing. A high resolution continuum tetrahedral mesh has been generated, where a sandwich model approach is adopted; the bones are represented as a stiffer cortical shells surrounding more flexible cancellous cores. Cartilage is included as a uniform thickness extruded layer and the effect of layer thickness is investigated. To realistically position the bones, gait analysis has been performed giving the 3D positions of the bones for the full gait cycle. Three phases of the gait cycle are examined using a finite volume based custom structural contact solver implemented in open-source software OpenFOAM.

Development of a patient-specific temporomandibular joint prosthesis according to the Groningen principle through a cadaver test series.

PubMed

Kraeima, J; Merema, B J; Witjes, M J H; Spijkervet, F K L

2018-05-01

Patients suffering from osteoarthritis, ankylosis (e.g. post-trauma or tumour) in the temporomandibular joint (TMJ) can present with symptoms such as severely restricted mouth opening, pain or other dynamic restrictions of the mandible. To alleviate the symptoms, a total joint prosthesis can be indicated, such as the Groningen TMJ prosthesis. This was developed as a stock device with a lowered centre of rotation for improved translational and opening capacity. This study aimed to improve the design of the prosthesis, and produce a workflow for a customized Groningen TMJ prosthesis, in order to make it more accurate and predictable. The fossa and mandibular components of the Groningen TMJ prosthesis were customized. A series of five human cadavers was operated and bilateral TMJ prostheses were placed using custom cutting and drilling guides. Placement accuracy was evaluated based on post-operative CT data. A total of N = 10 prostheses were placed and analysed. The average Euclidean distance deviation from planned to actual position was 0.81 mm (SD 0.21). All prostheses were placed according to the routine surgical approaches and had an excellent alignment with the bony structures. The newly developed custom Groningen TMJ prosthesis can be placed with great accuracy and is the first step for improving TMJ total joint replacement surgery. Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Fat metaplasia and backfill are key intermediaries in the development of sacroiliac joint ankylosis in patients with ankylosing spondylitis.

PubMed

Maksymowych, Walter P; Wichuk, Stephanie; Chiowchanwisawakit, Praveena; Lambert, Robert G; Pedersen, Susanne J

2014-11-01

Fat metaplasia in bone marrow on T1-weighted magnetic resonance imaging (MRI) scans may develop after resolution of inflammation in patients with ankylosing spondylitis (AS) and may predict new bone formation in the spine. Similar tissue, termed backfill, may also fill areas of excavated bone in the sacroiliac (SI) joints and may reflect resolution of inflammation and tissue repair at sites of erosions. The purpose of this study was to test our hypothesis that SI joint ankylosis develops following repair of erosions and that tissue characterized by fat metaplasia is a key intermediary step in this pathway. We used the Spondyloarthritis Research Consortium of Canada (SPARCC) SI structural lesion score (SSS) method to assess fat metaplasia, erosions, backfill, and ankylosis on MRIs of the SI joints in 147 patients with AS monitored for 2 years. Univariate and multivariate regression analyses focused first on identifying significant MRI predictors of new backfill and fat metaplasia. We then assessed the role of backfill and fat metaplasia in the development of new ankylosis. All analyses were adjusted for demographic features, treatment, and baseline and 2-year change in SSS values for parameters of inflammation and MRI structural lesions. Resolution of inflammation and reduction of erosions were each independently associated with the development of new backfill and fat metaplasia at 2 years on multivariate analyses. Multivariate regression analysis that included demographic features, baseline and 2-year change in parameters of inflammation and MRI structural lesion showed that reduction in erosions (P = 0.0005) and increase in fat metaplasia (P = 0.002) at 2 years was each independently associated with the development of new ankylosis. Our data support a disease model whereby ankylosis develops following repair of erosions, and fat metaplasia and backfill are key intermediary steps in this pathway. Copyright © 2014 by the American College of Rheumatology.

[Advances on biomechanics and kinematics of sprain of ankle joint].

PubMed

Zhao, Yong; Wang, Gang

2015-04-01

Ankle sprains are orthopedic clinical common disease, accounting for joint ligament sprain of the first place. If treatment is not timely or appropriate, the joint pain and instability maybe develop, and even bone arthritis maybe develop. The mechanism of injury of ankle joint, anatomical basis has been fully study at present, and the diagnostic problem is very clear. Along with the development of science and technology, biological modeling and three-dimensional finite element, three-dimensional motion capture system,digital technology study, electromyographic signal study were used for the basic research of sprain of ankle. Biomechanical and kinematic study of ankle sprain has received adequate attention, combined with the mechanism research of ankle sprain,and to explore the the biomechanics and kinematics research progress of the sprain of ankle joint.

Registration of knee joint surfaces for the in vivo study of joint injuries based on magnetic resonance imaging

NASA Astrophysics Data System (ADS)

Cheng, Rita W. T.; Habib, Ayman F.; Frayne, Richard; Ronsky, Janet L.

2006-03-01

In-vivo quantitative assessments of joint conditions and health status can help to increase understanding of the pathology of osteoarthritis, a degenerative joint disease that affects a large population each year. Magnetic resonance imaging (MRI) provides a non-invasive and accurate means to assess and monitor joint properties, and has become widely used for diagnosis and biomechanics studies. Quantitative analyses and comparisons of MR datasets require accurate alignment of anatomical structures, thus image registration becomes a necessary procedure for these applications. This research focuses on developing a registration technique for MR knee joint surfaces to allow quantitative study of joint injuries and health status. It introduces a novel idea of translating techniques originally developed for geographic data in the field of photogrammetry and remote sensing to register 3D MR data. The proposed algorithm works with surfaces that are represented by randomly distributed points with no requirement of known correspondences. The algorithm performs matching locally by identifying corresponding surface elements, and solves for the transformation parameters relating the surfaces by minimizing normal distances between them. This technique was used in three applications to: 1) register temporal MR data to verify the feasibility of the algorithm to help monitor diseases, 2) quantify patellar movement with respect to the femur based on the transformation parameters, and 3) quantify changes in contact area locations between the patellar and femoral cartilage at different knee flexion angles. The results indicate accurate registration and the proposed algorithm can be applied for in-vivo study of joint injuries with MRI.

Experimental characterization of deployable trusses and joints

NASA Technical Reports Server (NTRS)

Ikegami, R.; Church, S. M.; Keinholz, D. A.; Fowler, B. L.

1987-01-01

The structural dynamic properties of trusses are strongly affected by the characteristics of joints connecting the individual beam elements. Joints are particularly significant in that they are often the source of nonlinearities and energy dissipation. While the joints themselves may be physically simple, direct measurement is often necessary to obtain a mathematical description suitable for inclusion in a system model. Force state mapping is a flexible, practical test method for obtaining such a description, particularly when significant nonlinear effects are present. It involves measurement of the relationship, nonlinear or linear, between force transmitted through a joint and the relative displacement and velocity across it. An apparatus and procedure for force state mapping are described. Results are presented from tests of joints used in a lightweight, composite, deployable truss built by the Boeing Aerospace Company. The results from the joint tests are used to develop a model of a full 4-bay truss segment. The truss segment was statically and dynamically tested. The results of the truss tests are presented and compared with the analytical predictions from the model.

Joint hypermobility leading to osteoarthrosis and chondrocalcinosis.

PubMed

Bird, H A; Tribe, C R; Bacon, P A

1978-06-01

We have reviewed 21 adults referred to rheumatology clinic and considered to have generalised joint hypermobility by the criteria of Carter and Wilkinson (1964), modified by Beighton et al. (1973). They fell into two categories. 5 patients had a raised plasma viscosity (PV) and in each case a definite pathology was found to account for this, superimposed on hypermobile joints. The remaining 16 had a normal PV and this group was thought to represent the late natural history of hypermobility. 5 of these (aged 32 to 54 years) had no evidence of osteoarthrosis but the remaining 11 (aged 34 to 80 years) had widespread radiological osteoarthrosis. Synovial histology was obtained at arthroscopy in 6 of these patients and 4 (aged 60 to 75) had chondrocalcinosis. This previously undescribed finding may be the end result of hypermobile joints. Hypermobile patients with joint deformity (lax connective tissue), widespread synovial thickening (traumatic), and hot joint effusions (chondrocalcinosis) may mimic rheumatoid arthritis. They must be distinguished from patients who develop rheumatoid arthritis in hypermobile joints.

Joint hypermobility leading to osteoarthrosis and chondrocalcinosis.

PubMed Central

Bird, H A; Tribe, C R; Bacon, P A

1978-01-01

We have reviewed 21 adults referred to rheumatology clinic and considered to have generalised joint hypermobility by the criteria of Carter and Wilkinson (1964), modified by Beighton et al. (1973). They fell into two categories. 5 patients had a raised plasma viscosity (PV) and in each case a definite pathology was found to account for this, superimposed on hypermobile joints. The remaining 16 had a normal PV and this group was thought to represent the late natural history of hypermobility. 5 of these (aged 32 to 54 years) had no evidence of osteoarthrosis but the remaining 11 (aged 34 to 80 years) had widespread radiological osteoarthrosis. Synovial histology was obtained at arthroscopy in 6 of these patients and 4 (aged 60 to 75) had chondrocalcinosis. This previously undescribed finding may be the end result of hypermobile joints. Hypermobile patients with joint deformity (lax connective tissue), widespread synovial thickening (traumatic), and hot joint effusions (chondrocalcinosis) may mimic rheumatoid arthritis. They must be distinguished from patients who develop rheumatoid arthritis in hypermobile joints. Images PMID:686857

Self-referenced processing, neurodevelopment and joint attention in autism.

PubMed

Mundy, Peter; Gwaltney, Mary; Henderson, Heather

2010-09-01

This article describes a parallel and distributed processing model (PDPM) of joint attention, self-referenced processing and autism. According to this model, autism involves early impairments in the capacity for rapid, integrated processing of self-referenced (proprioceptive and interoceptive) and other-referenced (exteroceptive) information. Measures of joint attention have proven useful in research on autism because they are sensitive to the early development of the 'parallel' and integrated processing of self- and other-referenced stimuli. Moreover, joint attention behaviors are a consequence, but also an organizer of the functional development of a distal distributed cortical system involving anterior networks including the prefrontal and insula cortices, as well as posterior neural networks including the temporal and parietal cortices. Measures of joint attention provide early behavioral indicators of atypical development in this parallel and distributed processing system in autism. In addition it is proposed that an early, chronic disturbance in the capacity for integrating self- and other-referenced information may have cascading effects on the development of self awareness in autism. The assumptions, empirical support and future research implications of this model are discussed.

Foundation-industry relationships--a new business model joint-venture philanthropy in therapy development.

PubMed

Bartek, Ronald J

2014-01-01

The business model for medical therapy development has changed drastically. Large companies that once conducted their own Research and Development (R&D) and funded all the preclinical studies, all phases of clinical development and marketing of the products are increasingly turning to others for more and more of the earlier work in hopes of being able to in-license a de-risked program well downstream, take it through the final phases of clinical development and into the marketplace. This new paradigm has required patient-advocacy foundations, especially in the rare-disease space, to become far more effective in building relationships with all the players along the therapy-development pathway -- academic scientists, government agencies, other foundations with overlapping interests, biotechs, small biopharmaceutical entities and even the larger industry companies. From the perspective of the patient-advocacy community, these increasingly essential public-private partnerships have taken on the nature of what could be called joint-venture philanthropy and involve a broad spectrum of collaborations and financial relationships between foundations and industry partners that are not without concerns about potential conflicts of interest.

Design and clinical outcome of a novel 3D-printed prosthetic joint replacement for the human temporomandibular joint.

PubMed

Ackland, David; Robinson, Dale; Lee, Peter Vee Sin; Dimitroulis, George

2018-05-11

Stock prosthetic temporomandibular joint replacements come in limited sizes, and do not always encompass the joint anatomy that presents clinically. The aims of this study were twofold. Firstly, to design a personalized prosthetic total joint replacement for the treatment of a patient's end-stage temporomandibular joint osteoarthritis, to implant the prosthesis into the patient, and assess clinical outcome 12-months post-operatively; and secondly, to evaluate the influence of changes in prosthetic condyle geometry on implant load response during mastication. A 48-year-old female patient with Grade-5 osteoarthritis to the left temporomandibular joint was recruited, and a prosthesis developed to match the native temporomandibular joint anatomy. The prosthesis was 3D printed, sterilized and implanted into the patient, and pain and function measured 12-months post-operatively. The prosthesis load response during a chewing-bite and maximum-force bite was evaluated using a personalized multi-body musculoskeletal model. Simulations were performed after perturbing condyle thickness, neck length and head sphericity. Increases in prosthetic condyle neck length malaligned the mandible and perturbed temporomandibular joint force. Changes in condylar component thickness greatly influenced fixation screw stress response, while a more eccentric condylar head increased prosthetic joint-contact loading. Post-operatively, the prosthetic temporomandibular joint surgery reduced patient pain from 7/10 to 1/10 on a visual analog scale, and increased intercisal opening distance from 22 mm to 38 mm. This study demonstrates effectiveness of a personalized prosthesis that may ultimately be adapted to treat a wide-range of end-stage temporomandibular joint conditions, and highlights sensitivity of prosthesis load response to changes in condylar geometry. Copyright © 2018 Elsevier Ltd. All rights reserved.

[Fetal bone and joint disorders].

PubMed

Jakobovits, Akos

2008-12-21

The article discusses the physiology and pathology of fetal bone and joint development and functions. The bones provide static support for the body. The skull and the bones of spinal column encase the central and part of the peripheral nervous system. The ribs and the sternum shield the heart and the lungs, while the bones of the pelvis protect the intraabdominal organs. Pathological changes of these bony structures may impair the functions of the respective systems or internal organs. Movements of the bones are brought about by muscles. The deriving motions are facilitated by joints. Bony anomalies of the extremities limit their effective functions. Apart from skeletal and joint abnormalities, akinesia may also be caused by neurological, muscular and skin diseases that secondarily affect the functions of bones and joints. Such pathological changes may lead to various degrees of physical disability and even to death. Some of the mentioned anomalies are recognizable in utero by ultrasound. The diagnosis may serve as medical indication for abortion in those instances when the identified abnormality is incompatible with independent life.

The hindlimb in walking horses: 2. Net joint moments and joint powers.

PubMed

Clayton, H M; Hodson, E; Lanovaz, J L; Colborne, G R

2001-01-01

The objective of the study was to describe net joint moments and joint powers in the equine hindlimb during walking. The subjects were 5 sound horses. Kinematic and force data were collected synchronously and combined with morphometric information to determine net joint moments at each hindlimb joint throughout stance and swing. The results showed that the net joint moment was on the caudal/plantar side of all hindlimb joints at the start of stance when the limb was being actively retracted. It moved to the cranial/dorsal side around 24% stride at the hip and stifle and in terminal stance at the more distal joints. It remained on the cranial/dorsal side of all joints during the first half of swing to provide active limb protraction, then moved to the caudal/plantar aspect to reverse the direction of limb motion prior to ground contact. The hip joint was the main source of energy generation throughout the stride. It was assisted by the tarsal joint in both stance and swing phases and by the fetlock joint during the stance phase. The coffin joint acted as an energy damper during stance, whereas the stifle joint absorbed almost equal amounts of energy in the stance and swing phases. The coffin and fetlock joints absorbed energy as the limb was protracted and retracted during the swing phase, suggesting that their movements were driven by inertial forces. Future studies will apply these findings to detect changes in the energy profiles due to specific soft tissue injuries.

Intellectual Disability Policy as Developed, Expressed, and Evaluated in AAIDD/The Arc Joint Statements: The Role of Organization Position Statements.

PubMed

Luckasson, Ruth; Ford, Marty E; McMillan, Elise D; Misilo, Frederick M; Nygren, Margaret A

2017-07-01

The American Association on Intellectual and Developmental Disabilities (AAIDD) and The Arc of the United States (The Arc) have a long history of joined efforts to develop, express, and evaluate disability policies. These efforts have resulted in a series of formal statements on critical issues such as education, healthcare, human rights, and criminal justice. Their joint efforts further important policy goals including providing clear strong communication about important policy values and directions, promulgating key principles of high quality supports and services, affirming best professional practices, and emphasizing personal outcomes. In addition, the joint efforts (a) affirm important aspects of organization identity; (b) enhance the organizations' abilities to assure the input of a wide variety of perspectives; (c) engage members' expanded ranges of experiences and talents; (d) multiply staff and leadership resources; (e) increase communication strength and avenues; and (f) establish processes for timely review and revision of policies as critical disability issues arise or change, and new opportunities for policy integration and advancement occur. This article describes the processes used to develop, express, and evaluate the position statements; summarizes the policy content of several joint statements; and discusses the role of these organization position statements.

Spacesuit mobility knee joints

NASA Technical Reports Server (NTRS)

Vykukal, H. C. (Inventor)

1979-01-01

Pressure suit mobility joints are for use in interconnecting adjacent segments of an hermetically sealed spacesuit in which low torques, low leakage and a high degree of reliability are required. Each of the joints is a special purpose joint characterized by substantially constant volume and low torque characteristics and includes linkages which restrain the joint from longitudinal distension and includes a flexible, substantially impermeable diaphragm of tubular configuration spanning the distance between pivotally supported annuli. The diaphragms of selected joints include rolling convolutions for balancing the joints, while various joints include wedge-shaped sections which enhance the range of motion for the joints.

Sensate Scaffolds Can Reliably Detect Joint Loading

PubMed Central

Bliss, C. L.; Szivek, J. A.; Tellis, B. C.; Margolis, D. S.; Schnepp, A. B.; Ruth, J. T.

2008-01-01

Treatment of cartilage defects is essential to the prevention of osteoarthritis. Scaffold-based cartilage tissue engineering shows promise as a viable technique to treat focal defects. Added functionality can be achieved by incorporating strain gauges into scaffolds, thereby providing a real-time diagnostic measurement of joint loading. Strain-gauged scaffolds were placed into the medial femoral condyles of 14 adult canine knees and benchtop tested. Loads between 75 and 130 N were applied to the stifle joints at 30°, 50°, and 70° of flexion. Strain-gauged scaffolds were able to reliably assess joint loading at all applied flexion angles and loads. Pressure sensitive films were used to determine joint surface pressures during loading and to assess the effect of scaffold placement on joint pressures. A comparison of peak pressures in control knees and joints with implanted scaffolds, as well as a comparison of pressures before and after scaffold placement, showed that strain-gauged scaffold implantation did not significantly alter joint pressures. Future studies could possibly use strain-gauged scaffolds to clinically establish normal joint loads and to determine loads that are damaging to both healthy and tissue-engineered cartilage. Strain-gauged scaffolds may significantly aid the development of a functional engineered cartilage tissue substitute as well as provide insight into the native environment of cartilage. PMID:16941586

24 CFR 943.151 - What procurement standards apply to a joint venture itself?

Code of Federal Regulations, 2010 CFR

2010-04-01

... a joint venture itself? 943.151 Section 943.151 Housing and Urban Development Regulations Relating... HOUSING, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT PUBLIC HOUSING AGENCY CONSORTIA AND JOINT VENTURES Subsidiaries, Affiliates, Joint Ventures in Public Housing § 943.151 What procurement standards apply to a...

Characterization of the bending stiffness of large space structure joints

NASA Technical Reports Server (NTRS)

Wu, K. Chauncey

1989-01-01

A technique for estimating the bending stiffness of large space structure joints is developed and demonstrated for an erectable joint concept. Experimental load-deflection data from a three-point bending test was used as input to solve a closed-form expression for the joint bending stiffness which was derived from linear beam theory. Potential error sources in both the experimental and analytical procedures are identified and discussed. The bending stiffness of a mechanically preloaded erectable joint is studied at three applied moments and seven joint orientations. Using this technique, the joint bending stiffness was bounded between 6 and 17 percent of the bending stiffness of the graphite/epoxy strut member.

Early osteoarthritis of the patellofemoral joint.

PubMed

Arendt, Elizabeth A; Berruto, Massimo; Filardo, Giuseppe; Ronga, Mario; Zaffagnini, Stefano; Farr, Jack; Ferrua, Paolo; Grassi, Alberto; Condello, Vincenzo

2016-06-01

Patellofemoral joint cartilage lesions are associated with a variety of clinical situations including blunt trauma, lateral patella dislocations, or as a secondary development in the setting of abnormal joint loading. There is a need for more clarity on how to best address these lesions. Most specifically, when is it necessary to surgically treat these lesions of the patella and trochlea and which technique to use? This review will focus on the spectrum of patellofemoral disease/injury and their treatment strategies, with special emphasis on cartilage damage and early osteoarthritis. Chapter sections will review the most common scenarios of cartilage damage in the patellofemoral joint, with an attempt to summarize current treatment, their outcomes, remaining challenges and unanswered questions.

Joint Enabling Capabilities Command

Science.gov Websites

Executive Director Chief of Staff Joint Planning Support Element Joint Communications Support Element mission Joint Enabling Capabilities Command provides decisive joint communications, planning and public and responsive support for joint communications, planning and public affairs. Priorities * Deliver

Prevention of the Post-traumatic Fibrotic Response in Joints

DTIC Science & Technology

2014-10-01

The American journal of forensic medicine and pathology . 1988; 9(4):310-2. 14 APPENDICES: An abstract submitted for the ORS conference...clinical problem of posttraumatic joint stiffness, a pathology that reduces the range of motion (ROM) of injured joints and contributes to the...development of osteoarthritis. The fundamental hypothesis that drives the current study is that pathological fibrotic response of injured joint tissues

Development of Intra-knee Joint Sustained-Release Gel Formulation and Evaluation of Its Pharmacological Efficiency in Rats.

PubMed

Noda, Takehiro; Okuda, Tomoyuki; Ban, Kousuke; Mizuno, Ryota; Tagami, Tatsuaki; Ozeki, Tetsuya; Okamoto, Hirokazu

2017-06-01

In the development of a drug for intra-articular administration, a sustained-release formulation is desirable since it is difficult to sustain the effects of conventional injections due to fast drug leakage from the joint cavity. In this study, we prepared sustained release gel formulations for intra-articular administration containing indocyanine green (ICG) as a model drug to follow its fate after intra-articular administration in rats with in-vivo imaging system (IVIS). ICG administered as an aqueous solution leaked from the joint cavity in a short time and was excreted out of the body within a day. On the other hand, ICG in the sustained-release formulations was retained and released in the joint cavity for a week. Next, we prepared a sustained-release formulation with hyaluronic acid (HA) as the gel base containing a pain-relief drug (Drug A). We had administered it and other formulations into the rat knee where we injected bradykinin to evaluate their walking distance after 1 and 3 d. The effect of an aqueous solution of Drug A disappeared on day 3. The HA gel formulation without Drug A was more effective than the aqueous solution. The HA gel formulation with Drug A was the most effective; the walking distance was about 85% of the baseline on day 3. This study showed that the gel formulations were effective to sustain the release of a drug in the knee joint, and that the combination of a pain-relief drug with HA gel was effective to improve the mobility of the acute pain model rats.

Neuromuscular prehabilitation to prevent osteoarthritis after a traumatic joint injury.

PubMed

Tenforde, Adam S; Shull, Pete B; Fredericson, Michael

2012-05-01

Post-traumatic osteoarthritis (PTOA) is a process resulting from direct forces applied to a joint that cause injury and degenerative changes. An estimated 12% of all symptomatic osteoarthritis (OA) of the hip, knee, and ankle can be attributed to a post-traumatic cause. Neuromuscular prehabilitation is the process of improving neuromuscular function to prevent development of PTOA after an initial traumatic joint injury. Prehabilitation strategies include restoration of normative movement patterns that have been altered as the result of traumatic injury, along with neuromuscular exercises and gait retraining to prevent the development of OA after an injury occurs. A review of the current literature shows that no studies have been performed to evaluate methods of neuromuscular prehabilitation to prevent PTOA after a joint injury. Instead, current research has focused on management strategies after knee injuries, the value of exercise in the management of OA, and neuromuscular exercises after total knee arthroplasty. Recent work in gait retraining that alters knee joint loading holds promise for preventing the development of PTOA after joint trauma. Future research should evaluate methods of neuromuscular prehabilitation strategies in relationship to the outcome of PTOA after joint injury. Copyright © 2012 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Modified fluoroscopy-guided sacroiliac joint injection: a technical report.

PubMed

Liliang, Po-Chou; Liang, Cheng-Loong; Lu, Kang; Weng, Hui-Ching; Syu, Fei-Kai

2014-09-01

Sacroiliac joint (SIJ) injection can occasionally be challenging. We describe our experience in using conventional technique, and we developed an adjustment to overcome difficulties incurred. Conventional technique required superimposition of the posterior and anterior SIJ lines. If this technique failed to provide entry into the joint, fluoroscopy was slightly adjusted to obtain an oblique view. Of 50 SIJ injections, 29 (58%; 44-72%) were successfully performed using conventional technique. In another 21 procedures, 18 (85.7%; 64-99%) were subsequently completed using oblique view technique. The medial joint line, viewed from this angle, corresponded to the posterior joint line in 17 cases. The lateral joint line corresponded to the posterior joint line in one case. Oblique view technique can improve the success rate of SIJ injection. Wiley Periodicals, Inc.

Space Suit Joint Torque Measurement Method Validation

NASA Technical Reports Server (NTRS)

Valish, Dana; Eversley, Karina

2012-01-01

In 2009 and early 2010, a test method was developed and performed to quantify the torque required to manipulate joints in several existing operational and prototype space suits. This was done in an effort to develop joint torque requirements appropriate for a new Constellation Program space suit system. The same test method was levied on the Constellation space suit contractors to verify that their suit design met the requirements. However, because the original test was set up and conducted by a single test operator there was some question as to whether this method was repeatable enough to be considered a standard verification method for Constellation or other future development programs. In order to validate the method itself, a representative subset of the previous test was repeated, using the same information that would be available to space suit contractors, but set up and conducted by someone not familiar with the previous test. The resultant data was compared using graphical and statistical analysis; the results indicated a significant variance in values reported for a subset of the re-tested joints. Potential variables that could have affected the data were identified and a third round of testing was conducted in an attempt to eliminate and/or quantify the effects of these variables. The results of the third test effort will be used to determine whether or not the proposed joint torque methodology can be applied to future space suit development contracts.

Effects of Professional Development Training on Joint Attention Engagement in Low-Quality Childcare Centers

ERIC Educational Resources Information Center

Cain, David W.; Rudd, Loretta C.; Saxon, Terrill F.

2007-01-01

This study carries forward the exploration of joint attention engagement in children from 18 to 24 months of age enrolled in "low-quality" childcare centers. Childcare providers and children were videotaped to capture social interactions in the classroom including duration and bids for joint attention. One-half of 48 childcare providers…

Disclosing the temperature of columnar jointing in lavas.

PubMed

Lamur, Anthony; Lavallée, Yan; Iddon, Fiona E; Hornby, Adrian J; Kendrick, Jackie E; von Aulock, Felix W; Wadsworth, Fabian B

2018-04-12

Columnar joints form by cracking during cooling-induced contraction of lava, allowing hydrothermal fluid circulation. A lack of direct observations of their formation has led to ambiguity about the temperature window of jointing and its impact on fluid flow. Here we develop a novel thermo-mechanical experiment to disclose the temperature of columnar jointing in lavas. Using basalts from Eyjafjallajökull volcano (Iceland) we show that contraction during cooling induces stress build-up below the solidus temperature (980 °C), resulting in localised macroscopic failure between 890 and 840 °C. This temperature window for incipient columnar jointing is supported by modelling informed by mechanical testing and thermal expansivity measurements. We demonstrate that columnar jointing takes place well within the solid state of volcanic rocks, and is followed by a nonlinear increase in system permeability of <9 orders of magnitude during cooling. Columnar jointing may promote advective cooling in magmatic-hydrothermal environments and fluid loss during geothermal drilling and thermal stimulation.

A nondestructive, reproducible method of measuring joint reaction force at the distal radioulnar joint.

PubMed

Canham, Colin D; Schreck, Michael J; Maqsoodi, Noorullah; Doolittle, Madison; Olles, Mark; Elfar, John C

2015-06-01

To develop a nondestructive method of measuring distal radioulnar joint (DRUJ) joint reaction force (JRF) that preserves all periarticular soft tissues and more accurately reflects in vivo conditions. Eight fresh-frozen human cadaveric limbs were obtained. A threaded Steinmann pin was placed in the middle of the lateral side of the distal radius transverse to the DRUJ. A second pin was placed into the middle of the medial side of the distal ulna colinear to the distal radial pin. Specimens were mounted onto a tensile testing machine using a custom fixture. A uniaxial distracting force was applied across the DRUJ while force and displacement were simultaneously measured. Force-displacement curves were generated and a best-fit polynomial was solved to determine JRF. All force-displacement curves demonstrated an initial high slope where relatively large forces were required to distract the joint. This ended with an inflection point followed by a linear area with a low slope, where small increases in force generated larger amounts of distraction. Each sample was measured 3 times and there was high reproducibility between repeated measurements. The average baseline DRUJ JRF was 7.5 N (n = 8). This study describes a reproducible method of measuring DRUJ reaction forces that preserves all periarticular stabilizing structures. This technique of JRF measurement may also be suited for applications in the small joints of the wrist and hand. Changes in JRF can alter native joint mechanics and lead to pathology. Reliable methods of measuring these forces are important for determining how pathology and surgical interventions affect joint biomechanics. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Infrastructure Joint Venture Projects in Malaysia: A Preliminary Study

NASA Astrophysics Data System (ADS)

Romeli, Norsyakilah; Muhamad Halil, Faridah; Ismail, Faridah; Sufian Hasim, Muhammad

2018-03-01

As many developed country practise, the function of the infrastructure is to connect the each region of Malaysia holistically and infrastructure is an investment network projects such as transportation water and sewerage, power, communication and irrigations system. Hence, a billions allocations of government income reserved for the sake of the infrastructure development. Towards a successful infrastructure development, a joint venture approach has been promotes by 2016 in one of the government thrust in Construction Industry Transformation Plan which encourage the internationalisation among contractors. However, there is depletion in information on the actual practise of the infrastructure joint venture projects in Malaysia. Therefore, this study attempt to explore the real application of the joint venture in Malaysian infrastructure projects. Using the questionnaire survey, a set of survey question distributed to the targeted respondents. The survey contained three section which the sections are respondent details, organizations background and project capital in infrastructure joint venture project. The results recorded and analyse using SPSS software. The contractors stated that they have implemented the joint venture practice with mostly the client with the usual construction period of the infrastructure project are more than 5 years. Other than that, the study indicates that there are problems in the joint venture project in the perspective of the project capital and the railway infrastructure should be given a highlights in future study due to its high significant in term of cost and technical issues.

Incudomalleal joint formation: the roles of apoptosis, migration and downregulation

PubMed Central

Amin, Susan; Matalova, Eva; Simpson, Carol; Yoshida, Hiroki; Tucker, Abigail S

2007-01-01

Background The middle ear of mammals is composed of three endochondrial ossicles, the stapes, incus and malleus. Joints link the malleus to the incus and the incus to the stapes. In the mouse the first arch derived malleus and incus are formed from a single Sox9 and Type II collagen expressing condensation that later subdivides to give rise to two separate ossicles. In contrast the stapes forms from a separate condensation derived from the second branchial arch. Fusion of the malleus and incus is observed in a number of human syndromes and results in conductive hearing loss. Understanding how this joint forms during normal development is thus an important step in furthering our understanding of such defects. Results We show that the developing incudomalleal joint is characterised by a lack of proliferation and discrete areas of apoptosis. Apoptosis has been suggested to aid in the removal of pre-cartilaginous cells from the joint region, allowing for the physical separation of the cartilaginous elements, however, we show that joint initiation is unaffected by blocking apoptosis. There is also no evidence of cell migration out of the presumptive joint region, as observed by labelling of joint and ossicle cells in culture. Using Type II collagen lacZ reporter mice, however, it is evident that cells in the presumptive joint region remain in place and downregulate cartilage markers. Conclusion The malleus and incus first appear as a single united condensation expressing early cartilage markers. The incudomalleal joint region forms by cells in the presumptive joint region switching off cartilage markers and turning on joint markers. Failure in this process may result in fusion of this joint, as observed in human syndromes such as Branchio-Oto-Renal Syndrome or Treacher Collins Syndrome. PMID:18053235

Modelling of the Human Knee Joint Supported by Active Orthosis

NASA Astrophysics Data System (ADS)

Musalimov, V.; Monahov, Y.; Tamre, M.; Rõbak, D.; Sivitski, A.; Aryassov, G.; Penkov, I.

2018-02-01

The article discusses motion of a healthy knee joint in the sagittal plane and motion of an injured knee joint supported by an active orthosis. A kinematic scheme of a mechanism for the simulation of a knee joint motion is developed and motion of healthy and injured knee joints are modelled in Matlab. Angles between links, which simulate the femur and tibia are controlled by Simulink block of Model predictive control (MPC). The results of simulation have been compared with several samples of real motion of the human knee joint obtained from motion capture systems. On the basis of these analyses and also of the analysis of the forces in human lower limbs created at motion, an active smart orthosis is developed. The orthosis design was optimized to achieve an energy saving system with sufficient anatomy, necessary reliability, easy exploitation and low cost. With the orthosis it is possible to unload the knee joint, and also partially or fully compensate muscle forces required for the bending of the lower limb.

MP Joint Arthritis

MedlinePlus

... is extensive and severe, joint replacement or joint fusion are effective surgical options. Learn more about joint ... the tabs at the top (Video, Articles/WEB, Images, JHS, Products/Vendors), or the filters on the ...

Look At That! Video Chat and Joint Visual Attention Development Among Babies and Toddlers.

PubMed

McClure, Elisabeth R; Chentsova-Dutton, Yulia E; Holochwost, Steven J; Parrott, W G; Barr, Rachel

2018-01-01

Although many relatives use video chat to keep in touch with toddlers, key features of adult-toddler interaction like joint visual attention (JVA) may be compromised in this context. In this study, 25 families with a child between 6 and 24 months were observed using video chat at home with geographically separated grandparents. We define two types of screen-mediated JVA (across- and within-screen) and report age-related increases in the babies' across-screen JVA initiations, and that family JVA usage was positively related to babies' overall attention during video calls. Babies today are immersed in a digital world where formative relationships are often mediated by a screen. Implications for both infant social development and developmental research are discussed. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

Efficacy of Caregiver-Mediated Joint Engagement Intervention for Young Children with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Chiang, Chung-Hsin; Chu, Ching-Lin; Lee, Tsung-Chin

2016-01-01

Joint attention intervention for children with autism spectrum disorders was focused on improving joint engagement and joint attention skills. The purpose of this study was to develop a caregiver-mediated joint engagement intervention program combined with body movement play to investigate the effects of joint engagement/joint attention skills in…

Summary proceedings of the joint industry-FAA conference on the development and use of PC-based aviation training devices.

DOT National Transportation Integrated Search

1994-11-01

This report is a summarization of the proceedings of a joint industry FAA conference on the development and use of PC-based aviation training devices (PCATDs) that was held June 16-17, 1994, in Oklahoma City, Oklahoma. Attendees to the conference inc...

Results of arthroscopic joint debridement in different stages of chondromalacia of the knee joint.

PubMed

Krüger, T; Wohlrab, D; Birke, A; Hein, W

2000-01-01

A retrospective study was performed of 161 patients who had undergone arthroscopic operation for chondromalacia of the knee joint. After an average follow-up period of 40 (range 10-72) months, patients with severe articular cartilage lesions who had undergone articular lavage alone showed significantly poorer results (P < 0.001). With the same stage of chondromalacia and having undergone the same surgical procedure, younger patients showed better results than older patients. The more effective interruption of the circulus vitiosus during the development of degenerative joint diseases is the primary cause for better results achieved by mechanical debridement of the joint for patients suffering from grade 2 or higher. According to the literature, aggressive subchondral abrasion in severely degenerated knees does not show any benefits. Apparently, the success of the therapy depends to a great extent on the inferiority of the potential degenerative regenerate (lack of capacity of intrinsic regeneration of the hyaline cartilage) as well as on the grade and the progression of chondromalacia. Almost every second patient suffering from grade 4 chondromalacia complained of recurrent pain 1 year postoperatively. One of every 6 patients received a knee joint prosthesis within the 1st year. Therefore, the patients' preoperative expectations have to be clearly objectified. The surgical procedure as an operation with a low complication risk can also be justified as a temporary alternative to total knee arthroplasty in patients suffering from a high-grade degeneration of the joint.

Development of a revolute-joint robot for the precision positioning of an x-ray detector

NASA Astrophysics Data System (ADS)

Preissner, Curt A.; Royston, Thomas J.; Shu, Deming

2003-10-01

This paper profiles the initial phase in the development of a six degree-of-freedom robot, with 1 μm dynamic positioning uncertainty, for the manipulation of x-ray detectors or test specimens at the Advanced Photon Source (APS). While revolute-joint robot manipulators exhibit a smaller footprint along with increased positioning flexibility compared to Cartesian manipulators, commercially available revolute-joint manipulators do not meet our size, positioning, or environmental specifications. Currently, a robot with 20 μm dynamic positioning uncertainty is functioning at the APS for cryogenic crystallography sample pick-and-place operation. Theoretical, computational and experimental procedures are being used to (1) identify and (2) simulate the dynamics of the present robot system using a multibody approach, including the mechanics and control architecture, and eventually to (3) design an improved version with a 1 μm dynamic positioning uncertainty. We expect that the preceding experimental and theoretical techniques will be useful design and analysis tools as multi-degree-of-freedom manipulators become more prevalent on synchrotron beamlines.

Joint BioEnergy Institute

ScienceCinema

Keasling, Jay; Simmons, Blake; Tartaglino, Virginia; Baidoo, Edward; Kothari, Ankita

2018-05-11

The Joint BioEnergy Institute (JBEI) is a U.S. Department of Energy (DOE) Bioenergy Research Center dedicated to developing advanced biofuels—liquid fuels derived from the solar energy stored in plant biomass that can replace gasoline, diesel and jet fuels.

[Viscosity determination of synovial fluids from the canine hip and elbow joint as well as the human knee joint].

PubMed

Helms, Gabriele; Rittmann, Pia; Wefstaedt, Patrick; Windhagen, Henning; Pressel, Thomas; Behrens, Bernd-Arno; Nolte, Ingo

2008-01-01

The development of pathological changes in both human and canine hip joints is mainly caused by a lack of synovial fluid lubrication. This results in an increased joint abrasion. Even after implantation of joint prosthesis, inadequate lubrication can lead to abrasion in the tribological pair. This can finally result in aseptic loosening of the prosthesis. In spite of the enormous number of studies that have been performed on human, only little knowledge about the tribological properties of the joints in dogs is available in the literature. For this reason the viscosities of synovial fluid, derived from physiological and pathologically changed canine elbow joints were measured. The viscosities were determined by the use of a cone-plate viscometer at different temperatures and shear rates. The obtained values were compared with the viscosity values of pathologically changed synovial fluids from human knee joints as well as with pathological samples from the canine hip joint. The results show that the viscosity values vary within a series of measurements and are inversely proportional to the temperature of the sample and the shear rate. The differences between the average viscosities of canine and human synovial fluids taken from pathologically changed joints are below 4% (22.5 s(-1) at theta1 = 25 degrees C). The findings of this study are being implemented in a FE-Model for the computation of actual forces in the hip joint during different movements. This would represent a contribution to an improved prosthetic treatment of canine and human hips.

The Quest for Quality--Towards Joint European Quality Norms.

ERIC Educational Resources Information Center

Bartholomeus, Yvonne, Ed.; And Others

This book contains the following papers about considerations in developing joint European quality norms for vocational guidance: "Joint Quality Norms in Guidance"; "Careers Guidance in the Information Society" (Frans Meijers); "The Changing Nature of Guidance" (J. Chamberlain); "Quality with Policy: Beyond…

Technical feasibility of personalized articulating knee joint distraction for treatment of tibiofemoral osteoarthritis.

PubMed

Struik, T; Jaspers, J E N; Besselink, N J; van Roermund, P M; Plomp, S; Rudert, M J; Lafeber, F P J G; Mastbergen, S C

2017-11-01

Knee osteoarthritis is a highly prevalent degenerative joint disorder characterized by joint tissue damage and pain. Knee joint distraction has been introduced as a joint preserving surgical procedure to postpone knee arthroplasty. An often used standard externally fixation device for distraction poses a burden to patients due to the absence of joint flexion during the 6weeks treatment. Therefore, a personalized articulating distraction device was developed. The aim of this study was to test technical feasibility of this device. Based on an often applied rigid device, using equal bone pin positions and connectors, a hinge mechanism was developed consisting of a cam-following system for reproducing the complex joint-specific knee kinematics. In support, a device was developed for capturing the joint-specific sagittal plane articulation. The obtained kinematic data were translated into joint-specific cam shapes that were installed bilaterally in the hinge mechanism of the distraction device, as such providing personalized knee motion. Distraction of 5mm was performed within a range of motion of 30deg. joint flexion. Pre-clinical evaluation of the working principle was performed on human cadaveric legs and system stiffness characteristics were biomechanically evaluated. The desired range of motion was obtained and distraction was maintained under physiologically representative loading. Moreover, the joint-specific approach demonstrated tolerance of deviations from anatomical and alignment origin during initial placement of the developed distraction device. Articulation during knee distraction is considered technically feasible and has potential to decrease burden and improve acceptance of distraction therapy. Testing of clinical feasibility is warranted. Copyright © 2017 Elsevier Ltd. All rights reserved.

Joint Forward Operating Base Elements of Command and Control

NASA Astrophysics Data System (ADS)

Summers, William C.

2002-01-01

Since the 1986 Goldwater-Nichols Act directed the Chairman of the Joint Chiefs of Staff to develop doctrine for the joint employment of the armed forces, tactics, techniques, and procedures have evolved at different rates depending on the competency. Whereas the command of joint air forces is well prescribed within the structure of the air operations center and its associated leadership, command of air assets at a joint forward operating base lacks guidance. Today, the United States prosecutes an air war over Afghanistan from bases in Uzbekistan, Pakistan, and Afghanistan. Elements of the United States Army, Air Force, and Marines combine at these geographically minute locations, each bringing a certain complement of support and command and control. Evidence from operations during the 1999 air war for Kosovo at Tirana Rinas Airport in Albania suggests that when these service elements meet at the airfield for the first time, there are problems associated with local procedure. At best, time is wasted creating local joint systems to overcome the difficulties. At worst, safety and mission accomplishment are jeopardized. This thesis will address the need to develop doctrine and a jointly integrated organization to support the command and control function at a forward operating base.

Design/Analysis of the JWST ISIM Bonded Joints for Survivability at Cryogenic Temperatures

NASA Technical Reports Server (NTRS)

Bartoszyk, Andrew; Johnston, John; Kaprielian, Charles; Kuhn, Jonathan; Kunt, Cengiz; Rodini,Benjamin; Young, Daniel

1990-01-01

A major design and analysis challenge for the JWST ISIM structure is thermal survivability of metal/composite bonded joints below the cryogenic temperature of 30K (-405 F). Current bonded joint concepts include internal invar plug fittings, external saddle titanium/invar fittings and composite gusset/clip joints all bonded to M55J/954-6 and T300/954-6 hybrid composite tubes (75mm square). Analytical experience and design work done on metal/composite bonded joints at temperatures below that of liquid nitrogen are limited and important analysis tools, material properties, and failure criteria for composites at cryogenic temperatures are sparse in the literature. Increasing this challenge is the difficulty in testing for these required tools and properties at cryogenic temperatures. To gain confidence in analyzing and designing the ISIM joints, a comprehensive joint development test program has been planned and is currently running. The test program is designed to produce required analytical tools and develop a composite failure criterion for bonded joint strengths at cryogenic temperatures. Finite element analysis is used to design simple test coupons that simulate anticipated stress states in the flight joints; subsequently the test results are used to correlate the analysis technique for the final design of the bonded joints. In this work, we present an overview of the analysis and test methodology, current results, and working joint designs based on developed techniques and properties.

Modeling and optimization of joint quality for laser transmission joint of thermoplastic using an artificial neural network and a genetic algorithm

NASA Astrophysics Data System (ADS)

Wang, Xiao; Zhang, Cheng; Li, Pin; Wang, Kai; Hu, Yang; Zhang, Peng; Liu, Huixia

2012-11-01

A central composite rotatable experimental design(CCRD) is conducted to design experiments for laser transmission joining of thermoplastic-Polycarbonate (PC). The artificial neural network was used to establish the relationships between laser transmission joining process parameters (the laser power, velocity, clamp pressure, scanning number) and joint strength and joint seam width. The developed mathematical models are tested by analysis of variance (ANOVA) method to check their adequacy and the effects of process parameters on the responses and the interaction effects of key process parameters on the quality are analyzed and discussed. Finally, the desirability function coupled with genetic algorithm is used to carry out the optimization of the joint strength and joint width. The results show that the predicted results of the optimization are in good agreement with the experimental results, so this study provides an effective method to enhance the joint quality.

Joint angle sensors for closed-loop control

NASA Astrophysics Data System (ADS)

Ko, Wen H.; Miao, Chih-Lei

In order to substitute braces that have built-in goniometers and to provide feedback signals for closed loop control of lower extremity Functional Neuromuscular System in paraplegics, a stretchable capacitive sensor was developed to accurately detect angular movement in joints. Promising clinical evaluations on the knee joints of a paraplegic and a volunteer were done. The evaluations show great promise for the possibility of implantation applications.

Leakproof Swaged Joints in Thin-Wall Tubing

NASA Technical Reports Server (NTRS)

Stuckenberg, F. H.; Crockett, L. K.; Snyder, W. E.

1986-01-01

Tubular inserts reinforce joints, reducing incidence of leaks. In new swaging technique, tubular inserts placed inside ends of both tubes to be joined. Made from thicker-wall tubing with outside diameter that matches inside diameter of thin tubing swaged, inserts support tube ends at joint. They ensure more uniform contact between swage fitting and tubing. New swaging technique developed for Al/Ti/V-alloy hydraulic supply lines.

Joint sealant study

DOT National Transportation Integrated Search

1987-09-01

ADOT has approximately 550 lane miles of jointed portland cement pavement under its jurisdiction. The current practice is to saw and seal the joints at the time of construction and reseal the joints under a rehabilitation project. ADOT does not speci...

Estimation of ground reaction forces and joint moments on the basis on plantar pressure insoles and wearable sensors for joint angle measurement.

PubMed

Ostaszewski, Michal; Pauk, Jolanta

2018-05-16

Gait analysis is a useful tool medical staff use to support clinical decision making. There is still an urgent need to develop low-cost and unobtrusive mobile health monitoring systems. The goal of this study was twofold. Firstly, a wearable sensor system composed of plantar pressure insoles and wearable sensors for joint angle measurement was developed. Secondly, the accuracy of the system in the measurement of ground reaction forces and joint moments was examined. The measurements included joint angles and plantar pressure distribution. To validate the wearable sensor system and examine the effectiveness of the proposed method for gait analysis, an experimental study on ten volunteer subjects was conducted. The accuracy of measurement of ground reaction forces and joint moments was validated against the results obtained from a reference motion capture system. Ground reaction forces and joint moments measured by the wearable sensor system showed a root mean square error of 1% for min. GRF and 27.3% for knee extension moment. The correlation coefficient was over 0.9, in comparison with the stationary motion capture system. The study suggests that the wearable sensor system could be recommended both for research and clinical applications outside a typical gait laboratory.

Alterations of the Temporomandibular Joint on Magnetic Resonance Imaging according to Growth and Development in Schoolchildren

PubMed Central

Tanaka, Tatsurou; Konoo, Tetsuro; Habu, Manabu; Oda, Masafumi; Kito, Shinji; Kodama, Masaaki; Kokuryo, Shinya; Wakasugi-Sato, Nao; Matsumoto-Takeda, Shinobu; Nishida, Ikuko; Morikawa, Kazumasa; Saeki, Katsura; Maki, Kenshi; Tominaga, Kazuhiro; Masumi, Shin-ichi; Terashita, Masamichi; Morimoto, Yasuhiro

2012-01-01

The paper explains the alterations of the temporomandibular joint (TMJ) visualized by magnetic resonance imaging (MRI) according to the growth and development of schoolchildren. Appearance and disappearance of a “double contour-like structure” (DCLS) of the mandibular condyle on MRI according to the growth and development of schoolchildren were demonstrated. In addition, possible constituents of DCLS and the significance of detection of DCLS on MRI were also speculated. The relationship between red marrow and yellow marrow in the articular eminence of temporal bone, the disappearance of DCLS, and alterations of the mandibular condyle have been elucidated. PMID:23316233

Rewiring Warfighters for Joint Mindedness: Solutions for Joint Education in the 21st Century

DTIC Science & Technology

2010-06-01

begins " developing concepts to test the model or theory or plan for a forthcoming experience.൱ ELT provides a mechanism to reduce cognitive ...solving a lack of jointness requires a new way of thinking that focuses on developing cognitive symmetry among officers of different services... developing cognitive symmetry using P2C. Perception is the second P2C element. Creating cognitive symmetry through perception and not misperception

Elucidating the Role of Joint Disuse in the Development of Osteoarthritis following Return to High-Impact Loading

DTIC Science & Technology

2017-04-01

20 week old age point revealed a lack of response to joint unloading of the articular cartilage tidemark (interface of uncalcified and calcified...hallmark of disuse within this study. With this lack of response evident in our joint disuse model for 2 weeks of joint unloading for slightly older

Chronic bowel inflammation and inflammatory joint disease: Pathophysiology.

PubMed

Speca, Silvia; Dubuquoy, Laurent

2017-07-01

Bowel inflammation is closely linked to chronic joint inflammation. Research reported in the 1980s demonstrated bowel inflammation with gross and microscopic pathological features identical to those of Crohn's disease in over 60% of patients with spondyloarthritis (SpA). Numerous prospective studies have evidenced joint involvement in patients with chronic inflammatory bowel disease (IBD) and bowel inflammation in patients with SpA. Nevertheless, the interactions of joint disease and chronic bowel inflammation remain incompletely elucidated. Two main hypotheses have been suggested to explain potential links between inflammation of the mucosal immune system and peripheral arthritis: one identifies gut bacteria as potentially implicated in the development of joint inflammation and the other involves the recruitment of gut lymphocytes or activated macrophages to the joints. Pathophysiological investigations have established that HLA-B27 is a pivotal pathogenic factor. Here, we review current data on links between chronic bowel inflammation and inflammatory joint disease. Copyright © 2017 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

A Parallel and Distributed Processing Model of Joint Attention, Social-Cognition and Autism

PubMed Central

Mundy, Peter; Sullivan, Lisa; Mastergeorge, Ann M.

2009-01-01

Scientific Abstract The impaired development of joint attention is a cardinal feature of autism. Therefore, understanding the nature of joint attention is a central to research on this disorder. Joint attention may be best defined in terms of an information processing system that begins to develop by 4–6 months of age. This system integrates the parallel processing of internal information about one’s own visual attention with external information about the visual attention of other people. This type of joint encoding of information about self and other attention requires the activation of a distributed anterior and posterior cortical attention network. Genetic regulation, in conjunction with self-organizing behavioral activity guides the development of functional connectivity in this network. With practice in infancy the joint processing of self-other attention becomes automatically engaged as an executive function. It can be argued that this executive joint-attention is fundamental to human learning, as well as the development of symbolic thought, social-cognition and social-competence throughout the life span. One advantage of this parallel and distributed processing model of joint attention (PDPM) is that it directly connects theory on social pathology to a range of phenomenon in autism associated with neural connectivity, constructivist and connectionist models of cognitive development, early intervention, activity-dependent gene expression, and atypical ocular motor control. PMID:19358304

[Development and clinical application of a new type of anatomical locking plate for sternoclavicular joint fracture and dislocation].

PubMed

Sun, Yuanlin; Yang, Yunkang; Ge, Jianhua; Yang, Kun; Xiang, Feifan; Zhou, Ju; Liang, Jie

2018-03-01

To report a new type of anatomical locking plate for sternocalvicular joint, and investigate its effectiveness in treatment of sternoclavicular joint fracture and dislocation. A new type of anatomical locking plate for sternoclavicular joint was developed, which accorded with the anatomical features and biomechanical characteristics of Chinese sternoclavicular joint. By adopting the method of clinical randomized controlled study, 32 patients with the sternoclavicular joint fracture and dislocation who met the selection criteria between June 2008 and May 2015 were randomly divided into groups A and B ( n =16), and the patients were treated with new anatomic locking plate and distal radial T locking plate internal fixation, respectively. There was no significant difference between 2 groups in gender, age, injured side, body mass index, cause of injury, type of injury, the time from injury to operation, and preoperative Rockwood grading score ( P >0.05). The operation time, intraoperative blood loss, incision length, hospitalization time, and postoperative complications in 2 groups were recorded, and the effectiveness was evaluated by Rockwood grading score. The operations of 2 groups completed successfully. The operation time, intraoperative blood loss, and hospitalization time in group A were significantly less than those in group B ( P <0.05), but there was no significant difference in the incision length between 2 groups ( t =0.672, P =0.507). All the patients were followed up 18-30 months (mean, 24 months). In group A, there were 1 case of sternoclavicular joint pain and 2 cases of wound infection; in group B, there were 1 case of sternoclavicular joint pain, 1 case of internal fixation loosening, and 1 case of sternoclavicular joint re-dislocation; there was no significant difference in complication incidence between 2 groups ( P =1.000). The Rockwood grading scores at each time point after operation in 2 groups were significantly higher than those before

Joint swelling

MedlinePlus

... of arthritis caused by buildup of uric acid crystals in a joint ( gout ) Arthritis caused by wear ... osteoarthritis ) Arthritis caused by buildup of calcium-type crystals in joints ( pseudogout ) Disorder that involves arthritis and ...

The joint flanker effect and the joint Simon effect: On the comparability of processes underlying joint compatibility effects.

PubMed

Dittrich, Kerstin; Bossert, Marie-Luise; Rothe-Wulf, Annelie; Klauer, Karl Christoph

2017-09-01

Previous studies observed compatibility effects in different interference paradigms such as the Simon and flanker task even when the task was distributed across two co-actors. In both Simon and flanker tasks, performance is improved in compatible trials relative to incompatible trials if one actor works on the task alone as well as if two co-actors share the task. These findings have been taken to indicate that actors automatically co-represent their co-actor's task. However, recent research on the joint Simon and joint flanker effect suggests alternative non-social interpretations. To which degree both joint effects are driven by the same underlying processes is the question of the present study, and it was scrutinized by manipulating the visibility of the co-actor. While the joint Simon effect was not affected by the visibility of the co-actor, the joint flanker effect was reduced when participants did not see their co-actors but knew where the co-actors were seated. These findings provide further evidence for a spatial interpretation of the joint Simon effect. In contrast to recent claims, however, we propose a new explanation of the joint flanker effect that attributes the effect to an impairment in the focusing of spatial attention contingent on the visibility of the co-actor.

Revitalizing Nuclear Operations in the Joint Environment

DTIC Science & Technology

2014-02-01

height of the Cold War, US schol - ars and joint operational planners were working simultaneously on weapons development and operational art to employ...leadership’s large-target- category withholds thought necessary to maintain stability in a strategic crisis. The inclusion of nuclear effects and...escalation. The inclusion of these points in tomorrow’s doctrine as well as an intellec- tual discussion on the topic will inform Joint Staff planners

Design/analysis of the JWST ISIM bonded joints for survivability at cryogenic temperatures

NASA Astrophysics Data System (ADS)

Bartoszyk, Andrew; Johnston, John; Kaprielian, Charles; Kuhn, Jonathan; Kunt, Cengiz; Rodini, Benjamin; Young, Daniel

2005-08-01

A major design and analysis challenge for the JWST ISIM structure is thermal survivability of metal/composite adhesively bonded joints at the cryogenic temperature of 30K (-405°F). Current bonded joint concepts include internal invar plug fittings, external saddle titanium/invar fittings and composite gusset/clip joints all bonded to hybrid composite tubes (75mm square) made with M55J/954-6 and T300/954-6 prepregs. Analytical experience and design work done on metal/composite bonded joints at temperatures below that of liquid nitrogen are limited and important analysis tools, material properties, and failure criteria for composites at cryogenic temperatures are sparse in the literature. Increasing this challenge is the difficulty in testing for these required tools and properties at cryogenic temperatures. To gain confidence in analyzing and designing the ISIM joints, a comprehensive joint development test program has been planned and is currently running. The test program is designed to produce required analytical tools and develop a composite failure criterion for bonded joint strengths at cryogenic temperatures. Finite element analysis is used to design simple test coupons that simulate anticipated stress states in the flight joints; subsequently, the test results are used to correlate the analysis technique for the final design of the bonded joints. In this work, we present an overview of the analysis and test methodology, current results, and working joint designs based on developed techniques and properties.

Ultrasonic guided wave inspection of Inconel 625 brazed lap joints

NASA Astrophysics Data System (ADS)

Comot, Pierre; Bocher, Philippe; Belanger, Pierre

2016-04-01

The aerospace industry has been investigating the use of brazing for structural joints, as a mean of reducing cost and weight. There therefore is a need for a rapid, robust, and cost-effective non-destructive testing method for evaluating the structural integrity of the joints. The mechanical strength of brazed joints depends mainly on the amount of brittle phases in their microstructure. Ultrasonic guided waves offer the possibility of detecting brittle phases in joints using spatio-temporal measurements. Moreover, they offer the opportunity to inspect complex shape joints. This study focused on the development of a technique based on ultrasonic guided waves for the inspection of Inconel 625 lap joints brazed with BNi-2 filler metal. A finite element model of a lap joint was used to optimize the inspection parameters and assess the feasibility of detecting the amount of brittle phases in the joint. A finite element parametric study simulating the input signal shape, the center frequency, and the excitation direction was performed. The simulations showed that the ultrasonic guided wave energy transmitted through, and reflected from, the joints was proportional to the amount of brittle phases in the joint.

The Early Development of Joint Attention in Infants with Autistic Disorder Using Home Video Observations and Parental Interview

ERIC Educational Resources Information Center

Clifford, Sally M; Dissanayake, Cheryl

2008-01-01

The aim in the current study was to investigate the early development of joint attention, eye contact and affect during the first 2 years of life, by using retrospective parental interviews and analyses of home videos of infants who were later diagnosed with Autistic Disorder (AD). The 36 children with AD and the 27 matched control children were…

Rating Parent-Child Interactions: Joint Engagement, Communication Dynamics, and Shared Topics in Autism, Down Syndrome, and Typical Development

ERIC Educational Resources Information Center

Adamson, Lauren B.; Bakeman, Roger; Deckner, Deborah F.; Nelson, P. Brooke

2012-01-01

A battery of 17 rating items were applied to video records of typically-developing toddlers and young children with autism and Down syndrome interacting with their parents during the Communication Play Protocol. This battery provided a reliable and broad view of the joint engagement triad of child, partner, and shared topic. Ratings of the child's…

Adaptive Postural Control for Joint Immobilization during Multitask Performance

PubMed Central

Hsu, Wei-Li

2014-01-01

Motor abundance is an essential feature of adaptive control. The range of joint combinations enabled by motor abundance provides the body with the necessary freedom to adopt different positions, configurations, and movements that allow for exploratory postural behavior. This study investigated the adaptation of postural control to joint immobilization during multi-task performance. Twelve healthy volunteers (6 males and 6 females; 21–29 yr) without any known neurological deficits, musculoskeletal conditions, or balance disorders participated in this study. The participants executed a targeting task, alone or combined with a ball-balancing task, while standing with free or restricted joint motions. The effects of joint configuration variability on center of mass (COM) stability were examined using uncontrolled manifold (UCM) analysis. The UCM method separates joint variability into two components: the first is consistent with the use of motor abundance, which does not affect COM position (VUCM); the second leads to COM position variability (VORT). The analysis showed that joints were coordinated such that their variability had a minimal effect on COM position. However, the component of joint variability that reflects the use of motor abundance to stabilize COM (VUCM) was significant decreased when the participants performed the combined task with immobilized joints. The component of joint variability that leads to COM variability (VORT) tended to increase with a reduction in joint degrees of freedom. The results suggested that joint immobilization increases the difficulty of stabilizing COM when multiple tasks are performed simultaneously. These findings are important for developing rehabilitation approaches for patients with limited joint movements. PMID:25329477

Joint Acoustic and Modulation Frequency

NASA Astrophysics Data System (ADS)

Atlas, Les; Shamma, Shihab A.

2003-12-01

There is a considerable evidence that our perception of sound uses important features which is related to underlying signal modulations. This topic has been studied extensively via perceptual experiments, yet there are few, if any, well-developed signal processing methods which capitalize on or model these effects. We begin by summarizing evidence of the importance of modulation representations from psychophysical, physiological, and other sources. The concept of a two-dimensional joint acoustic and modulation frequency representation is proposed. A simple single sinusoidal amplitude modulator of a sinusoidal carrier is then used to illustrate properties of an unconstrained and ideal joint representation. Added constraints are required to remove or reduce undesired interference terms and to provide invertibility. It is then noted that the constraints would also apply to more general and complex cases of broader modulation and carriers. Applications in single-channel speaker separation and in audio coding are used to illustrate the applicability of this joint representation. Other applications in signal analysis and filtering are suggested.

Mutual coordination strengthens the sense of joint agency in cooperative joint action.

PubMed

Bolt, Nicole K; Poncelet, Evan M; Schultz, Benjamin G; Loehr, Janeen D

2016-11-01

Philosophers have proposed that when people coordinate their actions with others they may experience a sense of joint agency, or shared control over actions and their effects. However, little empirical work has investigated the sense of joint agency. In the current study, pairs coordinated their actions to produce tone sequences and then rated their sense of joint agency on a scale ranging from shared to independent control. People felt more shared than independent control overall, confirming that people experience joint agency during joint action. Furthermore, people felt stronger joint agency when they (a) produced sequences that required mutual coordination compared to sequences in which only one partner had to coordinate with the other, (b) held the role of follower compared to leader, and (c) were better coordinated with their partner. Thus, the strength of joint agency is influenced by the degree to which people mutually coordinate with each other's actions. Copyright © 2016 Elsevier Inc. All rights reserved.

Design considerations for bridge deck joint-sealing systems : summary report.

DOT National Transportation Integrated Search

1992-07-01

This is a report summary which summarizes a three year research effort related to the study of bridge deck expansion joint movements. Bridge deck expansion joint systems often develop serious problems requiring extensive and expensive maintenance. Th...

Joint Chiefs of Staff > Leadership

Science.gov Websites

Senior Enlisted Advisor Joint Staff History Joint Staff Inspector General Joint Staff Structure Origin of J8 | Force Structure, Resources & Assessment Contact Joint Staff Structure Joint Staff Organizational Chart Joint Chiefs of Staff Links Home Today in DOD About DOD Top Issues News Photos/Videos

Comparison of Extensive Thermal Cycling Effects on Microstructure Development in Micro-alloyed Sn-Ag-Cu Solder Joints

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, Iver E.; Boesenberg, Adam; Harringa, Joel

2011-09-28

Pb-free solder alloys based on the Sn-Ag-Cu (SAC) ternary eutectic have promise for widespread adoption across assembly conditions and operating environments, but enhanced microstructural control is needed. Micro-alloying with elements such as Zn was demonstrated for promoting a preferred solidification path and joint microstructure earlier in simple (Cu/Cu) solder joints studies for different cooling rates. This beneficial behavior now has been verified in reworked ball grid array (BGA) joints, using dissimilar SAC305 (Sn-3.0Ag-0.5Cu, wt.%) solder paste. After industrial assembly, BGA components joined with Sn-3.5Ag-0.74Cu-0.21Zn solder were tested in thermal cycling (-55 C/+125 C) along with baseline SAC305 BGA joints beyondmore » 3000 cycles with continuous failure monitoring. Weibull analysis of the results demonstrated that BGA components joined with SAC + Zn/SAC305 have less joint integrity than SAC305 joints, but their lifetime is sufficient for severe applications in consumer, defense, and avionics electronic product field environments. Failure analysis of the BGA joints revealed that cracking did not deviate from the typical top area (BGA component side) of each joint, in spite of different Ag3Sn blade content. Thus, SAC + Zn solder has not shown any advantage over SAC305 solder in these thermal cycling trials, but other characteristics of SAC + Zn solder may make it more attractive for use across the full range of harsh conditions of avionics or defense applications.« less

Can infants' orientation to social stimuli predict later joint attention skills?

PubMed

Schietecatte, Inge; Roeyers, Herbert; Warreyn, Petra

2012-06-01

From the moment infants are born, they seem to prefer orienting to social stimuli, over objects and non-social stimuli. This preference lasts throughout adulthood and is believed to play a crucial role in social-communicative development. By following up a group of infants at the age of 6, 8, and 12 months, this study explored the role of social orienting in the early development of joint attention skills. The expected association between social orienting and joint attention was partially confirmed. Social orienting in real-life photographs of everyday situations was not related to later joint attention skills, however fixation to the eyes in a neutral face was related to response to joint attention skills, and fixation to the eyes in a dynamic video clip of a talking person was predictive of initiating joint attention skills. Several alternative interpretations of the results are discussed. ©2011 The British Psychological Society.

Support and Development of Workflow Protocols for High Throughput Single-Lap-Joint Testing-Experimental

DTIC Science & Technology

2013-04-01

preparation, and presence of an overflow fillet for a high strength epoxy and ductile methacylate adhesive. A unique feature of this study was the...of expanding adhesive joint test configurations as part of the GEMS program. 15. SUBJECT TERMS single lap joint, adhesion, aluminum, epoxy ... epoxy and ductile methacylate adhesive. A unique feature of this study was the use of untrained GEMS (Gains in the Education of Mathematics and Sci

Development of a truss joint for robotic assembly of space structures

NASA Technical Reports Server (NTRS)

Parma, George F.

1992-01-01

This report presents the results of a detailed study of mechanical fasteners which were designed to facilitate robotic assembly of structures. Design requirements for robotic structural assembly were developed, taking into account structural properties and overall system design, and four candidate fasteners were designed to meet them. These fasteners were built and evaluated in the laboratory, and the Hammer-Head joint was chosen as superior overall. It had a high reliability of fastening under misalignments of 2.54 mm (0.1 in) and 3 deg, the highest end fixity (2.18), the simplest end effector, an integral capture guide, good visual verification, and the lightest weight (782 g, 1.72 lb). The study found that a good design should incorporate chamfers sliding on chamfers, cylinders sliding on chamfers, and hard surface finishes on sliding surfaces. The study also comments on robot flexibility, sag, hysteresis, thermal expansion, and friction which were observed during the testing.

Dynamic analysis of clamp band joint system subjected to axial vibration

NASA Astrophysics Data System (ADS)

Qin, Z. Y.; Yan, S. Z.; Chu, F. L.

2010-10-01

Clamp band joints are commonly used for connecting circular components together in industry. Some of the systems jointed by clamp band are subjected to dynamic load. However, very little research on the dynamic characteristics for this kind of joint can be found in the literature. In this paper, a dynamic model for clamp band joint system is developed. Contact and frictional slip between the components are accommodated in this model. Nonlinear finite element analysis is conducted to identify the model parameters. Then static experiments are carried out on a scaled model of the clamp band joint to validate the joint model. Finally, the model is adopted to study the dynamic characteristics of the clamp band joint system subjected to axial harmonic excitation and the effects of the wedge angle of the clamp band joint and the preload on the response. The model proposed in this paper can represent the nonlinearity of the clamp band joint and be used conveniently to investigate the effects of the structural and loading parameters on the dynamic characteristics of this type of joint system.

Is early osteoarthritis associated with differences in joint congruence?

PubMed Central

Conconi, Michele; Halilaj, Eni; Castelli, Vincenzo Parenti; Crisco, Joseph J.

2014-01-01

Previous studies suggest that osteoarthritis (OA) is related to abnormal or excessive articular contact stress. The peak pressure resulting from an applied load is determined by many factors, among which is shape and relative position and orientation of the articulating surfaces or, referring to a more common nomenclature, joint congruence. It has been hypothesized that anatomical differences may be among the causes of OA. Individuals with less congruent joints would likely develop higher peak pressure and thus would be more exposed to the risk of OA onset. The aim of this work was to determine if the congruence of the first carpometacarpal (CMC) joint differs with the early onset of OA or with sex, as the female population has a higher incidence of OA. 59 without and 38 with early OA were CT-scanned with their dominant or arthritic hand in a neutral configuration. The proposed measure of joint congruence is both shape and size dependent. The correlation of joint congruence with pathology and sex was analyzed both before and after normalization for joint size. We found a significant correlation between joint congruence and sex due to the sex-related differences in size. The observed correlation disappeared after normalization. Although joint congruence increased with size, it did not correlate significantly with the onset of early OA. Differences in joint congruence in this population may not be a primary cause of OA onset or predisposition, at least for the CMC joint. PMID:25468667

Novel joint cupping clinical maneuver for ultrasonographic detection of knee joint effusions.

PubMed

Uryasev, Oleg; Joseph, Oliver C; McNamara, John P; Dallas, Apostolos P

2013-11-01

Knee effusions occur due to traumatic and atraumatic causes. Clinical diagnosis currently relies on several provocative techniques to demonstrate knee joint effusions. Portable bedside ultrasonography (US) is becoming an adjunct to diagnosis of effusions. We hypothesized that a US approach with a clinical joint cupping maneuver increases sensitivity in identifying effusions as compared to US alone. Using unembalmed cadaver knees, we injected fluid to create effusions up to 10 mL. Each effusion volume was measured in a lateral transverse location with respect to the patella. For each effusion we applied a joint cupping maneuver from an inferior approach, and re-measured the effusion. With increased volume of saline infusion, the mean depth of effusion on ultrasound imaging increased as well. Using a 2-mm cutoff, we visualized an effusion without the joint cupping maneuver at 2.5 mL and with the joint cupping technique at 1 mL. Mean effusion diameter increased on average 0.26 cm for the joint cupping maneuver as compared to without the maneuver. The effusion depth was statistically different at 2.5 and 7.5 mL (P < .05). Utilizing a joint cupping technique in combination with US is a valuable tool in assessing knee effusions, especially those of subclinical levels. Effusion measurements are complicated by uneven distribution of effusion fluid. A clinical joint cupping maneuver concentrates the fluid in one recess of the joint, increasing the likelihood of fluid detection using US. © 2013 Elsevier Inc. All rights reserved.

Digital tomosynthesis rendering of joint margins for arthritis assessment

NASA Astrophysics Data System (ADS)

Duryea, Jeffrey W.; Neumann, Gesa; Yoshioka, Hiroshi; Dobbins, James T., III

2004-05-01

PURPOSE: Rheumatoid arthritis (RA) of the hand is a significant healthcare problem. Techniques to accurately quantity the structural changes from RA are crucial for the development and prescription of therapies. Analysis of radiographic joint space width (JSW) is widely used and has demonstrated promise. However, radiography presents a 2D view of the joint. In this study we performed tomosynthesis reconstructions of proximal interphalangeal (PIP), and metacarpophalangeal (MCP) joints to measure the 3D joint structure. METHODS: We performed a reader study using simulated radiographs of 12 MCP and 12 PIP joints from skeletal specimens imaged with micro-CT. The tomosynthesis technique provided images of reconstructed planes with 0.75 mm spacing, which were presented to 2 readers with a computer tool. The readers were instructed to delineate the joint surfaces on tomosynthetic slices where they could visualize the margins. We performed a quantitative analysis of 5 slices surrounding the central portion of each joint. Reader-determined JSW was compared to a gold standard. As a figure of merit we calculated the average root-mean square deviation (RMSD). RESULTS: RMSD was 0.22 mm for both joints. For the individual joints, RMSD was 0.18 mm (MCP), and 0.26 mm (PIP). The reduced performance for the smaller PIP joints suggests that a slice spacing less than 0.75 mm may be more appropriate. CONCLUSIONS: We have demonstrated the capability of limited 3D rendering of joint surfaces using digital tomosynthesis. This technique promises to provide an improved method to visualize the structural changes of RA.

Surgical Approaches to the Proximal Interphalangeal Joint.

PubMed

Cheah, Andre Eu-Jin; Yao, Jeffrey

2016-02-01

The proximal interphalangeal (PIP) joint may be affected by many conditions such as arthropathy, fractures, dislocations, and malunions. Whereas some of these conditions may be treated nonsurgically, many require open surgical intervention. Open interventions include implant arthroplasty or arthrodesis for arthropathy, open reduction internal fixation, or hemi-hamate arthroplasty for dorsal fracture-dislocations. Volar plate arthroplasty and corrective osteotomy for malunion about the PIP joint are also surgeries that may be required. The traditional approach to the PIP joint has been dorsal, which damages the delicate extensor apparatus with subsequent development of an extensor lag. This has led surgeons to explore volar and lateral approaches to the PIP joint. In this article, we describe each of these surgical approaches, discuss their advantages and disadvantages, and provide some guidance on which approach to choose based on the surgery that is to be performed. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

21 CFR 26.47 - Role and composition of the Joint Sectoral Committee.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Role and composition of the Joint Sectoral... EUROPEAN COMMUNITY Specific Sector Provisions for Medical Devices § 26.47 Role and composition of the Joint... joint assessment of the equivalence of conformity assessment bodies (CAB's); (2) Developing and...

Joint Command and Control of Cyber Operations: The Joint Force Cyber Component Command (JFCCC)

DTIC Science & Technology

2012-05-04

relies so heavily on complex command and control systems and interconnectivity in general, cyber warfare has become a serious topic of interest at the...defensive cyber warfare into current and future operations and plans. In particular, Joint Task Force (JTF) Commanders must develop an optimum method to

Adhesive Bonding Characterization of Composite Joints for Cryogenic Usage

NASA Technical Reports Server (NTRS)

Graf, Neil A.; Schieleit, Gregory F.; Biggs, Robert

2000-01-01

The development of polymer composite cryogenic tanks is a critical step in creating the next generation of launch vehicles. Future reusable launch vehicles need to minimize the gross liftoff weight (GLOW). This weight reduction is possible due to the large reduction in weight that composite materials can provide over current aluminum technology. In addition to composite technology, adhesively bonded joints potentially have several benefits over mechanically fastened joints, such as weight savings and cryogenic fluid containment. Adhesively bonded joints may be used in several areas of these cryogenic tanks, such as in lobe-to-lobe joints (in a multi-lobe concept), skirt-to-tank joint, strut-to-tank joint, and for attaching stringers and ring frames. The bonds, and the tanks themselves, must be able to withstand liquid cryogenic fuel temperatures that they contain. However, the use of adhesively bonded composite joints at liquid oxygen and hydrogen temperatures is largely unknown and must be characterized. Lockheed Martin Space Systems Company, Michoud Operations performed coupon-level tests to determine effects of material selection, cure process parameters, substrate surface preparation, and other factors on the strength of these composite joints at cryogenic temperatures. This led to the selection of a material and process that would be suitable for a cryogenic tank. KEY WORDS: Composites, Adhesive Bonding, Cryogenics

Shea Nut Oil Triterpene Concentrate Attenuates Knee Osteoarthritis Development in Rats: Evidence from Knee Joint Histology.

PubMed

Kao, Jen-Hsin; Lin, Sheng-Hsiung; Lai, Chun-Fu; Lin, Yu-Chieh; Kong, Zwe-Ling; Wong, Chih-Shung

2016-01-01

Shea nut oil triterpene concentrate is considered to have anti-inflammatory and antioxidant properties. Traditionally, it has been used to treat arthritic conditions in humans. This study aimed to investigate the effect of attenuating osteoarthritis (OA)-induced pain and joint destruction in rats by administering shea nut oil triterpene concentrate (SheaFlex75, which is more than 50% triterpenes). An anterior cruciate ligament transaction (ACLT) with medial meniscectomy (MMx) was used to induce OA in male Wistar rats. Different doses of SheaFlex75 (111.6 mg/kg, 223.2 mg/kg, and 446.4 mg/kg) were then intragastrically administered daily for 12 weeks after surgery. Body weight and the width of the knee joint were measured weekly. Additionally, incapacitance tests were performed at weeks 2, 4, 6, 8, 10 and 12 to measure the weight bearing of the hind limbs, and the morphology and histopathology of the medial femoral condyles were examined and were evaluated using the Osteoarthritis Research Society International (OARSI) scoring system. This study showed that SheaFlex75 reduced the swelling of the knee joint with OA and rectified its weight bearing after ACLT plus MMx surgery in rats. Treatment with SheaFlex75 also decreased ACLT plus MMx surgery-induced knee joint matrix loss and cartilage degeneration. SheaFlex75 relieves the symptoms of OA and protects cartilage from degeneration. SheaFlex75 thus has the potential to be an ideal nutraceutical supplement for joint protection, particularly for injured knee joints.

A clamping force measurement system for monitoring the condition of bolted joints on railway track joints and points

NASA Astrophysics Data System (ADS)

Tesfa, B.; Horler, G.; Thobiani, F. Al; Gu, F.; Ball, A. D.

2012-05-01

Many industrial structures associated with railway infrastructures rely on a large number of bolted joint connections to ensure safe and reliable operation of the track and trackside furniture. Significant sums of money are spent annually to repair the damage caused by bolt failures and to maintain the integrity of bolted structures. In the UK, Network Rail (the organization responsible for rail network maintenance and safety) conducts corrective and preventive maintenance manually on 26,000 sets of points (each having approximately 30 bolted joints per set), in order to ensure operational success and safety for the travelling public. Such manual maintenance is costly, disruptive, unreliable and prone to human error. The aim of this work is to provide a means of automatically measuring the clamping force of each individual bolted joint, by means of an instrumented washer. This paper describes the development of a sensor means to be used in the washer, which satisfies the following criteria. Sense changes in the clamping force of the joint and report this fact. Provide compatibility with the large dynamic range of clamping force. Satisfy the limitations in terms of physical size. Provide the means to electronically interface with the washer. Provide a means of powering the washer in situ. Provide a solution at an acceptable cost. Specifically the paper focuses on requirements 1, 2 and 3 and presents the results that support further development of the proposed design and the realization of a pre-prototype system. In the paper, various options for the force sensing element (strain gage, capacitor, piezo-resistive) have been compared, using design optimization techniques. As a result of the evaluation, piezo-resistive sensors in concert with a proprietary force attenuation method, have been found to offer the best performance and cost trade-off The performance of the novel clamping force sensor has been evaluated experimentally and the results show that a smart washer

Early, asymptomatic stage of degenerative joint disease in canine hip joints.

PubMed

Lust, G; Summers, B A

1981-11-01

The early stages of degenerative joint disease were investigated in coxofemoral joints from dogs with a hereditary predisposition to hip dysplasia. Alterations observed included mild nonsuppurative synovitis, increased volume of both synovial fluid and the ligamentum teres, and focal degenerative articular cartilage lesions. On radiologic examination, subluxation of the femoral head was seen, but only in the most severely affected joints. Synovial inflammation with increased synovial fluid and ligament volumes were indicators of early degenerative joint disease in dogs. These changes seemed to coincide with, or perhaps to precede, microscopic evidence for articular cartilage degeneration and occurred before radiologic abnormalities were detected.

Impact of 3-D seismic data on the Nigerian National Petroleum Corporation/Chevron Nigeria Limited joint venture development drilling program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Quam, S.

The Nigerian National Petroleum Corporation/Chevron Nigeria Limited joint venture has been acquiring three-dimensional (3-D) seismic data over its concessions since 1984. To date, 1700 km[sup 2] have been recorded and processed at a cumulative cost of US $39 million. During 1991 - 1992, 20 development wells were drilled based directly on new 3-D seismic interpretations. These wells have added 148 million bbl of oil in new recoverable reserves, and to date have added 37,000 bbl/day to the joint venture's production. In addition, the 3-D interpretations have resulted in a sizable inventory of wells for future development drilling. The new 3-Dmore » interpretations provided more accurate pictures of fault patterns, fluid contacts, channel trends, stratigraphic continuity, and velocity/amplitude anomalies. In addition, the 3-D data were invaluable in designing low risk, directional well trajectories to tap relatively thin oil legs under large gas caps. Wells often were programmed to hit several objectives at their respective gas/oil contacts, resulting in maximized net oil sand pays and reducing the risk of gas production. In order to do this, directional [open quotes]sharpshooting,[close quotes] accurate depth conversion of the seismic time maps, was critical. By using the 3-D seismic, checkshot, and sonic data to develop a variable velocity space, well-top prognoses within 50 ft at depths of 6,000-10,000 ft were possible, and were key to the success of the program. As the joint venture acreage becomes more mature, development wells will be drilled for smaller numbers of stacked objectives, and sometimes for single sands. Highly accurate 3-D interpretations and depth conversions will become even more critical in order to tap thinner pay zones in a cost-effect manner.« less

Joint Contact Stress

PubMed Central

Brand, Richard A

2005-01-01

A joint's normal mechanical history contributes to the maintenance of articular cartilage and underlying bone. Loading facilitates the flow of nutrients into cartilage and waste products away, and additionally provides the mechanical signals essential for normal cell and tissue maintenance. Deleteriously low or high contact stresses have been presumed to result in joint deterioration, and particular aspects of the mechanical environment may facilitate repair of damaged cartilage. For decades, investigators have explored static joint contact stresses (under some more or less arbitrary condition) as a surrogate of the relevant mechanical history. Contact stresses have been estimated in vitro in many joints and in a number of species, although only rarely in vivo. Despite a number of widely varying techniques (and spatial resolutions) to measure these contact stresses, reported ranges of static peak normal stresses are relatively similar from joint to joint across species, and in the range of 0.5 to 5.0 MPa. This suggests vertebrate diarthrodial joints have evolved to achieve similar mechanical design criteria. Available evidence also suggests some disorders of cartilage deterioration are associated with somewhat higher peak pressures ranging from 1-20 MPa, but overlapping the range of normal pressures. Some evidence and considerable logic suggests static contact stresses per se do not predict cartilage responses, but rather temporal aspects of the contact stress history. Static contact stresses may therefore not be a reasonable surrogate for biomechanical studies. Rather, temporal and spatial aspects of the loading history undoubtedly induce beneficial and deleterious biological responses. Finally, since all articular cartilage experiences similar stresses, the concept of a "weight-bearing" versus a "non-weight-bearing" joint seems flawed, and should be abandoned. PMID:16089079

Temporomandibular joint formation requires two distinct hedgehog-dependent steps.

PubMed

Purcell, Patricia; Joo, Brian W; Hu, Jimmy K; Tran, Pamela V; Calicchio, Monica L; O'Connell, Daniel J; Maas, Richard L; Tabin, Clifford J

2009-10-27

We conducted a genetic analysis of the developing temporo-mandibular or temporomandi-bular joint (TMJ), a highly specialized synovial joint that permits movement and function of the mammalian jaw. First, we used laser capture microdissection to perform a genome-wide expression analysis of each of its developing components. The expression patterns of genes identified in this screen were examined in the TMJ and compared with those of other synovial joints, including the shoulder and the hip joints. Striking differences were noted, indicating that the TMJ forms via a distinct molecular program. Several components of the hedgehog (Hh) signaling pathway are among the genes identified in the screen, including Gli2, which is expressed specifically in the condyle and in the disk of the developing TMJ. We found that mice deficient in Gli2 display aberrant TMJ development such that the condyle loses its growth-plate-like cellular organization and no disk is formed. In addition, we used a conditional strategy to remove Smo, a positive effector of the Hh signaling pathway, from chondrocyte progenitors. This cell autonomous loss of Hh signaling allows for disk formation, but the resulting structure fails to separate from the condyle. Thus, these experiments establish that Hh signaling acts at two distinct steps in disk morphogenesis, condyle initiation, and disk-condyle separation and provide a molecular framework for future studies of the TMJ.

Temporomandibular joint formation requires two distinct hedgehog-dependent steps

PubMed Central

Purcell, Patricia; Joo, Brian W.; Hu, Jimmy K.; Tran, Pamela V.; Calicchio, Monica L.; O'Connell, Daniel J.; Maas, Richard L.; Tabin, Clifford J.

2009-01-01

We conducted a genetic analysis of the developing temporo-mandibular or temporomandi-bular joint (TMJ), a highly specialized synovial joint that permits movement and function of the mammalian jaw. First, we used laser capture microdissection to perform a genome-wide expression analysis of each of its developing components. The expression patterns of genes identified in this screen were examined in the TMJ and compared with those of other synovial joints, including the shoulder and the hip joints. Striking differences were noted, indicating that the TMJ forms via a distinct molecular program. Several components of the hedgehog (Hh) signaling pathway are among the genes identified in the screen, including Gli2, which is expressed specifically in the condyle and in the disk of the developing TMJ. We found that mice deficient in Gli2 display aberrant TMJ development such that the condyle loses its growth-plate-like cellular organization and no disk is formed. In addition, we used a conditional strategy to remove Smo, a positive effector of the Hh signaling pathway, from chondrocyte progenitors. This cell autonomous loss of Hh signaling allows for disk formation, but the resulting structure fails to separate from the condyle. Thus, these experiments establish that Hh signaling acts at two distinct steps in disk morphogenesis, condyle initiation, and disk–condyle separation and provide a molecular framework for future studies of the TMJ. PMID:19815519

The design and development of a triaxial wear-testing joint simulator.

PubMed

Green, A S; O'Connell, M K; Lyons, A S; James, S P

1999-01-01

Most of the existing wear testers created to wear test total hip replacements, specifically the acetabular component, are designed to exert only an axial force and provide rotation in a close approximation of the actual femoral movement. The Rocky Mountain Joint Simulator was designed to exert three orthogonal forces and provide rotations about the X-, Y- and Z-axes to more closely simulate the physiological forces and motions found in the human gait cycle. The RMJS was also designed with adaptability for other joints, such as knees or canine hips, through the use of hydraulics and a computer-programmable control system. Such adaptability and functionality allows the researcher to more closely model a gait cycle, thereby obtaining wear patterns that resemble those found in retrieved implants more closely than existing simulators. Research is ongoing into the tuning and evaluation of the machine and preliminary acetabular component wear test results will be presented at the conference.

The National Guard: Recommendations to Develop the Joint Future Force

DTIC Science & Technology

2010-03-01

0209airpowerinafghan.pdf. 23 Statement of General James N. Mattis , USMC, Commander, United States Joint Forces Command, House Armed Services... James R. Locher III, Victory on the Potomac: the Goldwater-Nichols Act Unifies the Pentagon, (College Station: Texas A & M University Press, 2002), 19...pick snubs National Guard, Thursday January 14, 2010, Congress.org, http://www.congress.org/congressorg/ bio /userletter/?letter_id=4520675821

A personalized 3D-printed prosthetic joint replacement for the human temporomandibular joint: From implant design to implantation.

PubMed

Ackland, David C; Robinson, Dale; Redhead, Michael; Lee, Peter Vee Sin; Moskaljuk, Adrian; Dimitroulis, George

2017-05-01

Personalized prosthetic joint replacements have important applications in cases of complex bone and joint conditions where the shape and size of off-the-shelf components may not be adequate. The objective of this study was to design, test and fabricate a personalized 3D-printed prosthesis for a patient requiring total joint replacement surgery of the temporomandibular joint (TMJ). The new 'Melbourne' prosthetic TMJ design featured a condylar component sized specifically to the patient and fixation screw positions that avoid potential intra-operative damage to the mandibular nerve. The Melbourne prosthetic TMJ was developed for a 58-year-old female recipient with end-stage osteoarthritis of the TMJ. The load response of the prosthesis during chewing and a maximum-force bite was quantified using a personalized musculoskeletal model of the patient's masticatory system developed using medical images. The simulations were then repeated after implantation of the Biomet Microfixation prosthetic TMJ, an established stock device. The maximum condylar stresses, screw stress and mandibular stress at the screw-bone interface were lower in the Melbourne prosthetic TMJ (259.6MPa, 312.9MPa and 198.4MPa, respectively) than those in the Biomet Microfixation device (284.0MPa, 416.0MPa and 262.2MPa, respectively) during the maximum-force bite, with similar trends also observed during the chewing bite. After trialing surgical placement and evaluating prosthetic TMJ stability using cadaveric specimens, the prosthesis was fabricated using 3D printing, sterilized, and implanted into the female recipient. Six months post-operatively, the prosthesis recipient had a normal jaw opening distance (40.0 mm), with no complications identified. The new design features and immediate load response of the Melbourne prosthetic TMJ suggests that it may provide improved clinical and biomechanical joint function compared to a commonly used stock device, and reduce risk of intra-operative nerve damage

Strengthening of defected beam-column joints using CFRP.

PubMed

Mahmoud, Mohamed H; Afefy, Hamdy M; Kassem, Nesreen M; Fawzy, Tarek M

2014-01-01

This paper presents an experimental study for the structural performance of reinforced concrete (RC) exterior beam-column joints rehabilitated using carbon-fiber-reinforced polymer (CFRP). The present experimental program consists of testing 10 half-scale specimens divided into three groups covering three possible defects in addition to an adequately detailed control specimen. The considered defects include the absence of the transverse reinforcement within the joint core, insufficient bond length for the beam main reinforcement and inadequate spliced implanted column on the joint. Three different strengthening schemes were used to rehabilitate the defected beam-column joints including externally bonded CFRP strips and sheets in addition to near surface mounted (NSM) CFRP strips. The failure criteria including ultimate capacity, mode of failure, initial stiffness, ductility and the developed ultimate strain in the reinforcing steel and CFRP were considered and compared for each group for the control and the CFRP-strengthened specimens. The test results showed that the proposed CFRP strengthening configurations represented the best choice for strengthening the first two defects from the viewpoint of the studied failure criteria. On the other hand, the results of the third group showed that strengthening the joint using NSM strip technique enabled the specimen to outperform the structural performance of the control specimen while strengthening the joints using externally bonded CFRP strips and sheets failed to restore the strengthened joints capacity.

Joint Attention in Parent-Child Dyads Involving Children with Selective Mutism: A Comparison between Anxious and Typically Developing Children

ERIC Educational Resources Information Center

Nowakowski, Matilda E.; Tasker, Susan L.; Cunningham, Charles E.; McHolm, Angela E.; Edison, Shannon; St. Pierre, Jeff; Boyle, Michael H.; Schmidt, Louis A.

2011-01-01

Although joint attention processes are known to play an important role in adaptive social behavior in typical development, we know little about these processes in clinical child populations. We compared early school age children with selective mutism (SM; n = 19) versus mixed anxiety (MA; n = 18) and community controls (CC; n = 26) on joint…

Noninflammatory Joint Contractures Arising from Immobility: Animal Models to Future Treatments

PubMed Central

Wong, Kayleigh; Trudel, Guy; Laneuville, Odette

2015-01-01

Joint contractures, defined as the limitation in the passive range of motion of a mobile joint, can be classified as noninflammatory diseases of the musculoskeletal system. The pathophysiology is not well understood; limited information is available on causal factors, progression, the pathophysiology involved, and prediction of response to treatment. The clinical heterogeneity of joint contractures combined with the heterogeneous contribution of joint connective tissues to joint mobility presents challenges to the study of joint contractures. Furthermore, contractures are often a symptom of a wide variety of heterogeneous disorders that are in many cases multifactorial. Extended immobility has been identified as a causal factor and evidence is provided from both experimental and epidemiology studies. Of interest is the involvement of the joint capsule in the pathophysiology of joint contractures and lack of response to remobilization. While molecular pathways involved in the development of joint contractures are being investigated, current treatments focus on physiotherapy, which is ineffective on irreversible contractures. Future treatments may include early diagnosis and prevention. PMID:26247029

Infant Responding to Joint Attention, Executive Processes, and Self-Regulation in Preschool Children

PubMed Central

Van Hecke, Amy Vaughan; Mundy, Peter; Block, Jessica J.; Delgado, Christine E. F.; Parlade, Meaghan V.; Pomares, Yuly B.; Hobson, Jessica A.

2011-01-01

Infant joint attention is related to behavioral and social outcomes, as well as language in childhood. Recent research and theory suggests that the relations between joint attention and social-behavioral outcomes may reflect the role of executive self-regulatory processes in the development of joint attention. To test this hypothesis two- studies were conducted. The first, cross-sectional study examined the development of responding to joint attention skill (RJA) in terms of increasing executive efficiency of responding between 9 and 18 months of age. The results indicated that development of RJA was characterized by a decreased latency to shift attention in following another person’s gaze and head turn, as well as an increase in the proportion of correct RJA responses exhibited by older infants. The second study examined the longitudinal relations between 12-month measures of responding to joint attention (RJA) and 36-month attention regulation in a delay of gratification task. The results indicated that responding to joint attention at 12-months was significantly related to children’s use of three types of self-regulation behaviors while waiting for a snack reward at 36 months of age. These observations are discussed in light of a developmental theory of attention regulation and joint attention in infancy. PMID:22206892

M3FT-16OR020202112 - Report on viability of hydrothermal corrosion resistant SiC/SiC Joint development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katoh, Yutai; Koyanagi, Takaaki; Kiggans Jr, James O.

2016-06-30

Hydrothermal corrosion of four types of the silicon carbide (SiC) to SiC plate joints were investigated under PWR and BWR relevant chemical conditions without irradiation. The joints were formed by metal diffusion bonding using molybdenum or titanium interlayer, reaction sintering using Ti-Si-C system, and SiC nanopowder sintering. Most of the formed joints withstood the corrosion tests for five weeks. The recession of the SiC substrates was limited. Based on the recession rate of the bonding layers, it was concluded that all the joints except for the molybdenum diffusion bond are promising under the reducing activity environments. The SiC nanopowder sinteredmore » joint was the most corrosion tolerant under the oxidizing activity environment among the four joints.« less

Development and validation of a computational model of the knee joint for the evaluation of surgical treatments for osteoarthritis

PubMed Central

Mootanah, R.; Imhauser, C.W.; Reisse, F.; Carpanen, D.; Walker, R.W.; Koff, M.F.; Lenhoff, M.W.; Rozbruch, S.R.; Fragomen, A.T.; Dewan, Z.; Kirane, Y.M.; Cheah, Pamela A.; Dowell, J.K.; Hillstrom, H.J.

2014-01-01

A three-dimensional (3D) knee joint computational model was developed and validated to predict knee joint contact forces and pressures for different degrees of malalignment. A 3D computational knee model was created from high-resolution radiological images to emulate passive sagittal rotation (full-extension to 65°-flexion) and weight acceptance. A cadaveric knee mounted on a six-degree-of-freedom robot was subjected to matching boundary and loading conditions. A ligament-tuning process minimised kinematic differences between the robotically loaded cadaver specimen and the finite element (FE) model. The model was validated by measured intra-articular force and pressure measurements. Percent full scale error between EE-predicted and in vitro-measured values in the medial and lateral compartments were 6.67% and 5.94%, respectively, for normalised peak pressure values, and 7.56% and 4.48%, respectively, for normalised force values. The knee model can accurately predict normalised intra-articular pressure and forces for different loading conditions and could be further developed for subject-specific surgical planning. PMID:24786914

Development and validation of a computational model of the knee joint for the evaluation of surgical treatments for osteoarthritis.

PubMed

Mootanah, R; Imhauser, C W; Reisse, F; Carpanen, D; Walker, R W; Koff, M F; Lenhoff, M W; Rozbruch, S R; Fragomen, A T; Dewan, Z; Kirane, Y M; Cheah, K; Dowell, J K; Hillstrom, H J

2014-01-01

A three-dimensional (3D) knee joint computational model was developed and validated to predict knee joint contact forces and pressures for different degrees of malalignment. A 3D computational knee model was created from high-resolution radiological images to emulate passive sagittal rotation (full-extension to 65°-flexion) and weight acceptance. A cadaveric knee mounted on a six-degree-of-freedom robot was subjected to matching boundary and loading conditions. A ligament-tuning process minimised kinematic differences between the robotically loaded cadaver specimen and the finite element (FE) model. The model was validated by measured intra-articular force and pressure measurements. Percent full scale error between FE-predicted and in vitro-measured values in the medial and lateral compartments were 6.67% and 5.94%, respectively, for normalised peak pressure values, and 7.56% and 4.48%, respectively, for normalised force values. The knee model can accurately predict normalised intra-articular pressure and forces for different loading conditions and could be further developed for subject-specific surgical planning.

Radiologic changes of ankle joint after total knee arthroplasty.

PubMed

Lee, Jung Hee; Jeong, Bi O

2012-12-01

The authors noticed that ankle joint osteoarthritis was not uncommon when lower extremity malalignment, such as a knee varus deformity, was present as a result of severe osteoarthritis of the knee. The purpose of this study was to analyze radiologic changes of the ankle joint after total knee arthroplasty. This study included 142 cases in 110 patients who underwent total knee arthroplasty and were followed for at least 3 years. The varus knee group included 128 cases and the valgus knee group included 14 cases. On anteroposterior standing lower extremity radiographs, varus and valgus angles of the knee were measured preoperatively and at the last follow-up. The angle between the ground surface and the distal tibial plafond as well as the upper talus was also measured. In addition, tibial anterior surface angle, talar tilt, space between the medial malleolar distal tip and the medial articular surface of the talus, and medial tibiotalar joint space of the ankle joint were measured. Out of 142 cases, 50 (35.2%) had arthritis in the ankle before total knee arthroplasty and 31 (21.8%) had newly developed or progressive arthritis after surgery. In particular, the varus knee group demonstrated statistically significant differences in preoperative varus deformity, preoperative talar tilt, and postoperative correction angle between the cases that developed or had progressive arthritis and those that did not show any changes (p < .05). After total knee arthroplasty, arthritis developed or progressed in the ankle of many cases radiographically. In particular, when the preoperative talar tilt increased medial to the ankle or the postoperative correction angle was large, the incidence of arthritis in the ankle joint increased. The authors recommend more cautious follow-up on the symptoms of the ankle joint after total knee arthroplasty.

Modeling Progressive Failure of Bonded Joints Using a Single Joint Finite Element

NASA Technical Reports Server (NTRS)

Stapleton, Scott E.; Waas, Anthony M.; Bednarcyk, Brett A.

2010-01-01

Enhanced finite elements are elements with an embedded analytical solution which can capture detailed local fields, enabling more efficient, mesh-independent finite element analysis. In the present study, an enhanced finite element is applied to generate a general framework capable of modeling an array of joint types. The joint field equations are derived using the principle of minimum potential energy, and the resulting solutions for the displacement fields are used to generate shape functions and a stiffness matrix for a single joint finite element. This single finite element thus captures the detailed stress and strain fields within the bonded joint, but it can function within a broader structural finite element model. The costs associated with a fine mesh of the joint can thus be avoided while still obtaining a detailed solution for the joint. Additionally, the capability to model non-linear adhesive constitutive behavior has been included within the method, and progressive failure of the adhesive can be modeled by using a strain-based failure criteria and re-sizing the joint as the adhesive fails. Results of the model compare favorably with experimental and finite element results.

Joint torques and joint reaction forces during squatting with a forward or backward inclined Smith machine.

PubMed

Biscarini, Andrea; Botti, Fabio M; Pettorossi, Vito E

2013-02-01

We developed a biomechanical model to determine the joint torques and loadings during squatting with a backward/forward-inclined Smith machine. The Smith squat allows a large variety of body positioning (trunk tilt, foot placement, combinations of joint angles) and easy control of weight distribution between forefoot and heel. These distinctive aspects of the exercise can be managed concurrently with the equipment inclination selected to unload specific joint structures while activating specific muscle groups. A backward (forward) equipment inclination decreases (increases) knee torque, and compressive tibiofemoral and patellofemoral forces, while enhances (depresses) hip and lumbosacral torques. For small knee flexion angles, the strain-force on the posterior cruciate ligament increases (decreases) with a backward (forward) equipment inclination, whereas for large knee flexion angles, this behavior is reversed. In the 0 to 60 degree range of knee flexion angles, loads on both cruciate ligaments may be simultaneously suppressed by a 30 degree backward equipment inclination and selecting, for each value of the knee angle, specific pairs of ankle and hip angles. The anterior cruciate ligament is safely maintained unloaded by squatting with backward equipment inclination and uniform/forward foot weight distribution. The conditions for the development of anterior cruciate ligament strain forces are clearly explained.

Analysis of postmarket complaints database for the iFuse SI Joint Fusion System®: a minimally invasive treatment for degenerative sacroiliitis and sacroiliac joint disruption

PubMed Central

Miller, Larry E; Reckling, W Carlton; Block, Jon E

2013-01-01

Background The sacroiliac joint is a common but under-recognized source of low back and gluteal pain. Patients with degenerative sacroiliitis or sacroiliac joint disruption resistant to nonsurgical treatments may undergo open surgery with sacroiliac joint arthrodesis, although outcomes are mixed and risks are significant. Minimally invasive sacroiliac joint arthrodesis was developed to minimize the risk of iatrogenic injury and to improve patient outcomes compared with open surgery. Methods Between April 2009 and January 2013, 5319 patients were treated with the iFuse SI Joint Fusion System® for conditions including sacroiliac joint disruption and degenerative sacroiliitis. A database was prospectively developed to record all complaints reported to the manufacturer in patients treated with the iFuse device. Complaints were collected through spontaneous reporting mechanisms in support of ongoing mandatory postmarket surveillance efforts. Results Complaints were reported in 204 (3.8%) patients treated with the iFuse system. Pain was the most commonly reported clinical complaint (n = 119, 2.2%), with nerve impingement (n = 48, 0.9%) and recurrent sacroiliac joint pain (n = 43, 0.8%) most frequently cited. All other clinical complaints were rare (≤0.2%). Ninety-six revision surgeries were performed in 94 (1.8%) patients at a median follow-up of four (range 0–30) months. Revisions were typically performed in the early postoperative period for treatment of a symptomatic malpositioned implant (n = 46, 0.9%) or to correct an improperly sized implant in an asymptomatic patient (n = 10, 0.2%). Revisions in the late postoperative period were performed to treat symptom recurrence (n = 34, 0.6%) or for continued pain of undetermined etiology (n = 6, 0.1%). Conclusion Analysis of a postmarket product complaints database demonstrates an overall low risk of complaints with the iFuse SI Joint Fusion System in patients with degenerative sacroiliitis or sacroiliac joint

Analysis of postmarket complaints database for the iFuse SI Joint Fusion System®: a minimally invasive treatment for degenerative sacroiliitis and sacroiliac joint disruption.

PubMed

Miller, Larry E; Reckling, W Carlton; Block, Jon E

2013-01-01

The sacroiliac joint is a common but under-recognized source of low back and gluteal pain. Patients with degenerative sacroiliitis or sacroiliac joint disruption resistant to nonsurgical treatments may undergo open surgery with sacroiliac joint arthrodesis, although outcomes are mixed and risks are significant. Minimally invasive sacroiliac joint arthrodesis was developed to minimize the risk of iatrogenic injury and to improve patient outcomes compared with open surgery. Between April 2009 and January 2013, 5319 patients were treated with the iFuse SI Joint Fusion System® for conditions including sacroiliac joint disruption and degenerative sacroiliitis. A database was prospectively developed to record all complaints reported to the manufacturer in patients treated with the iFuse device. Complaints were collected through spontaneous reporting mechanisms in support of ongoing mandatory postmarket surveillance efforts. Complaints were reported in 204 (3.8%) patients treated with the iFuse system. Pain was the most commonly reported clinical complaint (n = 119, 2.2%), with nerve impingement (n = 48, 0.9%) and recurrent sacroiliac joint pain (n = 43, 0.8%) most frequently cited. All other clinical complaints were rare (≤0.2%). Ninety-six revision surgeries were performed in 94 (1.8%) patients at a median follow-up of four (range 0-30) months. Revisions were typically performed in the early postoperative period for treatment of a symptomatic malpositioned implant (n = 46, 0.9%) or to correct an improperly sized implant in an asymptomatic patient (n = 10, 0.2%). Revisions in the late postoperative period were performed to treat symptom recurrence (n = 34, 0.6%) or for continued pain of undetermined etiology (n = 6, 0.1%). Analysis of a postmarket product complaints database demonstrates an overall low risk of complaints with the iFuse SI Joint Fusion System in patients with degenerative sacroiliitis or sacroiliac joint disruption.

Modeling of Human Joint Structures.

DTIC Science & Technology

1982-09-01

Acromioclavicular Joint .... ............. ... 20 Glenohumeral Joint .... ................ . 20 HIP JOINT .................. ...... 21 Iliofemoral Ligament...clavicle articulates with the manubrium of the sternum, and the acromioclavicular joint, where the clavicle articulates with the acromion process of the...the interclavicular ligament. Acromioclavicular Joint This articulation between the distal end of the clavicle and the acromion of the scapula is

Joint Chiefs of Staff > Media

Science.gov Websites

Senior Enlisted Advisor Joint Staff History Joint Staff Inspector General Joint Staff Structure Origin of J8 | Force Structure, Resources & Assessment Contact Joint Staff Media News Videos Chairman's

Perceptions and misconceptions regarding the Joint Commission's view of quality monitoring.

PubMed

Patterson, C H

1989-10-01

The Joint Commission recently has revised its hospital standards for infection control to reflect more accurately current state-of-the-art practices. In addition, the Joint Commission's Agenda for Change initiatives include the development of clinical indicators; one of the topics that will be included in those clinical indicator sets will be infection control. How the hospital chooses to organize itself to conduct the historically required monitoring and evaluation of clinical patient care currently required by the standards of the Joint Commission is at the option of the hospital. How the hospital will organize and collect data specific to infection control indicators yet to be developed by the Joint Commission has not been determined and will not be defined until specific research and development projects are completed. The hospital is expected to have in place infection prevention, surveillance, and control programs; it also is expected to have in place a quality assurance program that focuses not only on solving identified problems but also on the improvement of patient care quality. How the hospitals organize and/or integrate these activities is also at its option. It is expected that qualified professionals will direct and enforce infection prevention, surveillance, and control practices; indicators for infection control can provide data that will help assess the relative success of those practices and activities. The Joint Commission is not developing the capability to judge, on its own part, the actual quality of care provided by an organization seeking accreditation. Rather, the Joint Commission is committed to developing more accurate means to evaluate the structures, processes, and outcomes of diagnosis and treatment activities, as well as their interrelationships. Clinical excellence is supported by quality in the organizational environment and the managerial and leadership contexts within which patient care is delivered. Both clinical and

Is early osteoarthritis associated with differences in joint congruence?

PubMed

Conconi, Michele; Halilaj, Eni; Parenti Castelli, Vincenzo; Crisco, Joseph J

2014-12-18

Previous studies suggest that osteoarthritis (OA) is related to abnormal or excessive articular contact stress. The peak pressure resulting from an applied load is determined by many factors, among which is shape and relative position and orientation of the articulating surfaces or, referring to a more common nomenclature, joint congruence. It has been hypothesized that anatomical differences may be among the causes of OA. Individuals with less congruent joints would likely develop higher peak pressure and thus would be more exposed to the risk of OA onset. The aim of this work was to determine if the congruence of the first carpometacarpal (CMC) joint differs with the early onset of OA or with sex, as the female population has a higher incidence of OA. 59 without and 38 with early OA were CT-scanned with their dominant or arthritic hand in a neutral configuration. The proposed measure of joint congruence is both shape and size dependent. The correlation of joint congruence with pathology and sex was analyzed both before and after normalization for joint size. We found a significant correlation between joint congruence and sex due to the sex-related differences in size. The observed correlation disappeared after normalization. Although joint congruence increased with size, it did not correlate significantly with the onset of early OA. Differences in joint congruence in this population may not be a primary cause of OA onset or predisposition, at least for the CMC joint. Copyright © 2014 Elsevier Ltd. All rights reserved.

Experimental joint immobilization in guinea pigs. Effects on the knee joint

NASA Technical Reports Server (NTRS)

Marcondesdesouza, J. P.; Machado, F. F.; Sesso, A.; Valeri, V.

1980-01-01

In young and adult guinea pigs, the aftermath experimentally induced by the immobilization of the knee joint in hyperextended forced position was studied. Joint immobilization which varied from one to nine weeks was attained by plaster. Eighty knee joints were examined macro and microscopically. Findings included: (1) muscular hypotrophy and joint stiffness in all animals, directly proportional to the length of immobilization; (2) haemoarthrosis in the first week; (3) intra-articular fibrous tissue proliferation ending up with fibrous ankylosis; (4) hyaline articular cartilage erosions; (5) various degrees of destructive menisci changes. A tentative explanation of the fibrous tissue proliferation and of the cartilage changes is offered.

Shea Nut Oil Triterpene Concentrate Attenuates Knee Osteoarthritis Development in Rats: Evidence from Knee Joint Histology

PubMed Central

Lin, Sheng-Hsiung; Lai, Chun-Fu; Lin, Yu-Chieh; Kong, Zwe-Ling; Wong, Chih-Shung

2016-01-01

Background Shea nut oil triterpene concentrate is considered to have anti-inflammatory and antioxidant properties. Traditionally, it has been used to treat arthritic conditions in humans. This study aimed to investigate the effect of attenuating osteoarthritis (OA)-induced pain and joint destruction in rats by administering shea nut oil triterpene concentrate (SheaFlex75, which is more than 50% triterpenes). Methods An anterior cruciate ligament transaction (ACLT) with medial meniscectomy (MMx) was used to induce OA in male Wistar rats. Different doses of SheaFlex75 (111.6 mg/kg, 223.2 mg/kg, and 446.4 mg/kg) were then intragastrically administered daily for 12 weeks after surgery. Body weight and the width of the knee joint were measured weekly. Additionally, incapacitance tests were performed at weeks 2, 4, 6, 8, 10 and 12 to measure the weight bearing of the hind limbs, and the morphology and histopathology of the medial femoral condyles were examined and were evaluated using the Osteoarthritis Research Society International (OARSI) scoring system. Results This study showed that SheaFlex75 reduced the swelling of the knee joint with OA and rectified its weight bearing after ACLT plus MMx surgery in rats. Treatment with SheaFlex75 also decreased ACLT plus MMx surgery-induced knee joint matrix loss and cartilage degeneration. Conclusion SheaFlex75 relieves the symptoms of OA and protects cartilage from degeneration. SheaFlex75 thus has the potential to be an ideal nutraceutical supplement for joint protection, particularly for injured knee joints. PMID:27583436

Blockade of Dickkopf (DKK)-1 induces fusion of sacroiliac joints.

PubMed

Uderhardt, S; Diarra, D; Katzenbeisser, J; David, J-P; Zwerina, J; Richards, W; Kronke, G; Schett, G

2010-03-01

To study whether Dickkopf (DKK)-1, an inhibitor of wingless (Wnt) signalling, is involved in the fusion of sacroiliac joints. Mice transgenic for tumour necrosis factor (TNFtg mice), which develop bilateral sacroiliitis, were treated with vehicle, anti-TNF antibody or anti-DKK1 antibody. Sacroiliac joints were analysed for histological signs of inflammation, bone erosion, osteoclast formation and ankylosis. Moreover, expression of collagen type X, beta-catenin and DKK-1 was assessed by immunohistochemistry. There were no signs of spontaneous ankylosis of the sacroiliac joints in TNFtg mice. TNF blockade effectively reduced inflammation, bone erosion and osteoclast numbers in the sacroiliac joints, but did not lead to ankylosis. Blockade of DKK1 had no effect on inflammatory signs of sacroiliitis, but significantly reduced bone erosions and osteoclast counts. Moreover, DKK1 blockade promoted expression of collagen type X, the formation of hypertrophic chondrocytes and ankylosis of sacroiliac joints. DKK1 influences inflammatory remodelling of sacroiliac joints by prevention of joint ankylosis. This may indicate an important role of the Wnt signalling pathway in the structural bone changes of axial joint disease. Although this model does not reflect the entire spectrum of ankylosing spondylitis in humans, it helps to explain the pathophysiological processes of sacroiliac joint ankylosis, which is a hallmark of the spondyloarthritides.

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.

An experimentally based nonlinear viscoelastic model of joint passive moment.

PubMed

Esteki, A; Mansour, J M

1996-04-01

Previous investigations have not converged on a generally accepted model of the dissipative part of joint passive moment. To provide a basis for developing a model, a series of measurements were performed to characterize the passive moment at the metacarpophalangeal joint of the index finger. Two measurement procedures were used, one in moment relaxation over a range of fixed joint angles and the other at a series of constant joint velocities. Fung's quasi-linear viscoelastic theory motivated the development of the passive moment model. Using this approach, it was not necessary to make restrictive assumptions regarding the viscoelastic behavior of the passive moment. The generality of the formulation allowed specific functions to be chosen based on experimental data rather than finding coefficients which attempted to fit a preselected model of the data. It was shown that a nonlinear viscoelastic model described the passive stiffness. No significant frictional effects were found. Of particular importance was the nonlinear behavior of the dissipative part of the passive moment which was modeled by joint speed raised to a power less than one. This result could explain the differing findings among previous investigations, and may have important implications for control of limb movement.

Joint Light Tactical Vehicle (JLTV): Background and Issues for Congress

DTIC Science & Technology

2017-01-10

Joint Light Tactical Vehicle (JLTV): Background and Issues for Congress Andrew Feickert Specialist in Military Ground Forces January 10, 2017......Congressional Research Service Summary The Joint Light Tactical Vehicle (JLTV) is being developed by the Army and the Marine Corps as a successor to the High

Analytical and Experimental Assessment of Seismic Vulnerability of Beam-Column Joints without Transverse Reinforcement in Concrete Buildings

NASA Astrophysics Data System (ADS)

Hassan, Wael Mohammed

Beam-column joints in concrete buildings are key components to ensure structural integrity of building performance under seismic loading. Earthquake reconnaissance has reported the substantial damage that can result from inadequate beam-column joints. In some cases, failure of older-type corner joints appears to have led to building collapse. Since the 1960s, many advances have been made to improve seismic performance of building components, including beam-column joints. New design and detailing approaches are expected to produce new construction that will perform satisfactorily during strong earthquake shaking. Much less attention has been focused on beam-column joints of older construction that may be seismically vulnerable. Concrete buildings constructed prior to developing details for ductility in the 1970s normally lack joint transverse reinforcement. The available literature concerning the performance of such joints is relatively limited, but concerns about performance exist. The current study aimed to improve understanding and assessment of seismic performance of unconfined exterior and corner beam-column joints in existing buildings. An extensive literature survey was performed, leading to development of a database of about a hundred tests. Study of the data enabled identification of the most important parameters and the effect of each parameter on the seismic performance. The available analytical models and guidelines for strength and deformability assessment of unconfined joints were surveyed and evaluated. In particular, The ASCE 41 existing building document proved to be substantially conservative in joint shear strength estimation. Upon identifying deficiencies in these models, two new joint shear strength models, a bond capacity model, and two axial capacity models designed and tailored specifically for unconfined beam-column joints were developed. The proposed models strongly correlated with previous test results. In the laboratory testing phase of

Multispectral diffuse optical tomography of finger joints

NASA Astrophysics Data System (ADS)

Lighter, Daniel; Filer, Andrew; Dehghani, Hamid

2017-07-01

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by synovial inflammation. The current treatment paradigm for earlier, more aggressive therapy places importance on development of functional imaging modalities, capable of quantifying joint changes at the earliest stages. Diffuse optical tomography (DOT) has shown great promise in this regard, due to its cheap, non-invasive, non-ionizing and high contrast nature. Underlying pathological activity in afflicted joints leads to altered optical properties of the synovial region, with absorption and scattering increasing. Previous studies have used these optical changes as features for classifying diseased joints from healthy. Non-tomographic, single wavelength, continuous wave (CW) measurements of trans-illuminated joints have previously reported achieving this with specificity and sensitivity in the range 80 - 90% [1]. A single wavelength, frequency domain DOT system, combined with machine learning techniques, has been shown to achieve sensitivity and specificity in the range of 93.8 - 100% [2]. A CW system is presented here which collects data at 5 wavelengths, enabling reconstruction of pathophysiological parameters such as oxygenation and total hemoglobin, with the aim of identifying localized hypoxia and angiogenesis associated with inflammation in RA joints. These initial studies focus on establishing levels of variation in recovered parameters from images of healthy controls.

78 FR 7464 - Large Scale Networking (LSN) ; Joint Engineering Team (JET)

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-01

... NATIONAL SCIENCE FOUNDATION Large Scale Networking (LSN) ; Joint Engineering Team (JET) AGENCY: The Networking and Information Technology Research and Development (NITRD) National Coordination...://www.nitrd.gov/nitrdgroups/index.php?title=Joint_Engineering_Team_ (JET)#title. SUMMARY: The JET...

Effect of Strain Rate on Joint Strength and Failure Mode of Lead-Free Solder Joints

NASA Astrophysics Data System (ADS)

Lin, Jian; Lei, Yongping; Fu, Hanguang; Guo, Fu

2018-03-01

In surface mount technology, the Sn-3.0Ag-0.5Cu solder joint has a shorter impact lifetime than a traditional lead-tin solder joint. In order to improve the impact property of SnAgCu lead-free solder joints and identify the effect of silver content on tensile strength and impact property, impact experiments were conducted at various strain rates on three selected SnAgCu based solder joints. It was found that joint failure mainly occurred in the solder material with large plastic deformation under low strain rate, while joint failure occurred at the brittle intermetallic compound layer without any plastic deformation at a high strain rate. Joint strength increased with the silver content in SnAgCu alloys in static tensile tests, while the impact property of the solder joint decreased with increasing silver content. When the strain rate was low, plastic deformation occurred with failure and the tensile strength of the Sn-3.0Ag-0.5Cu solder joint was higher than that of Sn-0.3Ag-0.7Cu; when the strain rate was high, joint failure mainly occurred at the brittle interface layer and the Sn-0.3Ag-0.7Cu solder joint had a better impact resistance with a thinner intermetallic compound layer.

Joint Center Estimation Using Single-Frame Optimization: Part 1: Numerical Simulation.

PubMed

Frick, Eric; Rahmatalla, Salam

2018-04-04

The biomechanical models used to refine and stabilize motion capture processes are almost invariably driven by joint center estimates, and any errors in joint center calculation carry over and can be compounded when calculating joint kinematics. Unfortunately, accurate determination of joint centers is a complex task, primarily due to measurements being contaminated by soft-tissue artifact (STA). This paper proposes a novel approach to joint center estimation implemented via sequential application of single-frame optimization (SFO). First, the method minimizes the variance of individual time frames’ joint center estimations via the developed variance minimization method to obtain accurate overall initial conditions. These initial conditions are used to stabilize an optimization-based linearization of human motion that determines a time-varying joint center estimation. In this manner, the complex and nonlinear behavior of human motion contaminated by STA can be captured as a continuous series of unique rigid-body realizations without requiring a complex analytical model to describe the behavior of STA. This article intends to offer proof of concept, and the presented method must be further developed before it can be reasonably applied to human motion. Numerical simulations were introduced to verify and substantiate the efficacy of the proposed methodology. When directly compared with a state-of-the-art inertial method, SFO reduced the error due to soft-tissue artifact in all cases by more than 45%. Instead of producing a single vector value to describe the joint center location during a motion capture trial as existing methods often do, the proposed method produced time-varying solutions that were highly correlated ( r > 0.82) with the true, time-varying joint center solution.

The Joint Master Operational Planner

DTIC Science & Technology

2016-04-04

Daniel H. Hibner, United States Army Joint Forces Staff College Joint Advanced Warfighting School 7800 Hampton Blvd. Norfolk, VA 23511-1702 Approved...Operational Art. Unclass Unclass Unclass Unclassified Unlimited 66 757-443-6301 NATIONAL DEFENSE UNIVERSITY JOINT FORCES STAFF COLLEGE JOINT ADVANCED...of this paper reflect my own personal views and are not necessarily endorsed by the Joint Forces Staff College or the department of Defense. Thesis

Neuromuscular interfacing: establishing an EMG-driven model for the human elbow joint.

PubMed

Pau, James W L; Xie, Shane S Q; Pullan, Andrew J

2012-09-01

Assistive devices aim to mitigate the effects of physical disability by aiding users to move their limbs or by rehabilitating through therapy. These devices are commonly embodied by robotic or exoskeletal systems that are still in development and use the electromyographic (EMG) signal to determine user intent. Not much focus has been placed on developing a neuromuscular interface (NI) that solely relies on the EMG signal, and does not require modifications to the end user's state to enhance the signal (such as adding weights). This paper presents the development of a flexible, physiological model for the elbow joint that is leading toward the implementation of an NI, which predicts joint motion from EMG signals for both able-bodied and less-abled users. The approach uses musculotendon models to determine muscle contraction forces, a proposed musculoskeletal model to determine total joint torque, and a kinematic model to determine joint rotational kinematics. After a sensitivity analysis and tuning using genetic algorithms, subject trials yielded an average root-mean-square error of 6.53° and 22.4° for a single cycle and random cycles of movement of the elbow joint, respectively. This helps us to validate the elbow model and paves the way toward the development of an NI.

Joint kinematics of surgeons during lumbar pedicle screw placement.

PubMed

Park, Jeong-Yoon; Kim, Kyung-Hyun; Kuh, Sung-Uk; Chin, Dong-Kyu; Kim, Keun-Su; Cho, Yong-Eun

2016-12-01

A surgical robot for spine surgery has recently been developed. The objective is to assess the joint kinematics of the surgeon during spine surgery. We enrolled 18 spine surgeons, who each performed pedicle screw placement, and used an optoelectronic motion analysis system. Using three-dimensional (3D) motion images, distance changes in five joints and angle changes in six joints were calculated during surgery. Distance fluctuations increased gradually from the proximal to the distal joint. Angle fluctuations were largest at the distal point but did not gradually increase, and the elbow showed the second largest fluctuation. Changes along the X axis were larger than those of the Y and Z axes. The distances gradually increased from proximal portions of the body to the hand. In angle changes, the elbow was most dynamic during pedicle screw placement. The surgeons' whole joints carry out a harmonic role during lumbar pedicle screw placement. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Cellular Pressure-Actuated Joint

NASA Technical Reports Server (NTRS)

McGuire, John R.

2003-01-01

A modification of a pressure-actuated joint has been proposed to improve its pressure actuation in such a manner as to reduce the potential for leakage of the pressurizing fluid. The specific joint for which the modification is proposed is a field joint in a reusable solid-fuel rocket motor (RSRM), in which the pressurizing fluid is a mixture of hot combustion gases. The proposed modification could also be applicable to other pressure-actuated joints of similar configuration.

Reusable Solid Rocket Motor Nozzle Joint-4 Thermal Analysis

NASA Technical Reports Server (NTRS)

Clayton, J. Louie

2001-01-01

This study provides for development and test verification of a thermal model used for prediction of joint heating environments, structural temperatures and seal erosions in the Space Shuttle Reusable Solid Rocket Motor (RSRM) Nozzle Joint-4. The heating environments are a result of rapid pressurization of the joint free volume assuming a leak path has occurred in the filler material used for assembly gap close out. Combustion gases flow along the leak path from nozzle environment to joint O-ring gland resulting in local heating to the metal housing and erosion of seal materials. Analysis of this condition was based on usage of the NASA Joint Pressurization Routine (JPR) for environment determination and the Systems Improved Numerical Differencing Analyzer (SINDA) for structural temperature prediction. Model generated temperatures, pressures and seal erosions are compared to hot fire test data for several different leak path situations. Investigated in the hot fire test program were nozzle joint-4 O-ring erosion sensitivities to leak path width in both open and confined joint geometries. Model predictions were in generally good agreement with the test data for the confined leak path cases. Worst case flight predictions are provided using the test-calibrated model. Analysis issues are discussed based on model calibration procedures.

Mechanics of Suture Joints

NASA Astrophysics Data System (ADS)

Li, Yaning; Song, Juha; Ortiz, Christine; Boyce, Mary; Ortiz Group/DMSE/MIT Team; Boyce Group/ME/MIT Team

2011-03-01

Biological sutures are joints which connect two stiff skeletal or skeletal-like components. These joints possess a wavy geometry with a thin organic layer providing adhesion. Examples of biological sutures include mammalian skulls, the pelvic assembly of the armored fish Gasterosteus aculeatus (the three-spined stickleback), and the suture joints in the shell of the red-eared slider turtle. Biological sutures allow for movement and compliance, control stress concentrations, transmit loads, reduce fatigue stress and absorb energy. In this investigation, the mechanics of the role of suture geometry in providing a naturally optimized joint is explored. In particular, analytical and numerical micromechanical models of the suture joint are constructed. The anisotropic mechanical stiffness and strength are studied as a function of suture wavelength, amplitude and the material properties of the skeletal and organic components, revealing key insights into the optimized nature of these ubiquitous natural joints.

Generalised joint hypermobility and knee joint hypermobility: prevalence, knee joint symptoms and health-related quality of life in a Danish adult population.

PubMed

Junge, Tina; Henriksen, Peter; Hansen, Sebrina; Østengaard, Lasse; Golightly, Yvonne M; Juul-Kristensen, Birgit

2017-10-27

Several biomechanical factors, such as knee joint hypermobility (KJH), are suggested to play a role in the etiology of knee joint symptoms and knee osteoarthritis. Nevertheless, the prevalence or consequences of KJH solely or included in the classification of generalized joint hypermobility (GJHk) is unknown for a general population. Therefore, the objectives were to report the prevalence of self-reported GJHk and KJH, as well as the association of these conditions to knee joint symptoms, severity and duration of symptoms, and health-related quality of life (HRQoL) in a Danish adult population. This study is a cross-sectional population-based survey of 2056 Danish adults. Respondents received online questionnaires of GJHk and KJH, knee joint symptoms, the severity and duration of these, as well as HRQoL. Total response rate was 49% (n = 1006). The prevalence of self-reported GJHk and KJH was 13% and 23%, mostly representing women. More than half of the respondents with GJHk and KJH had knee joint symptoms. The odds for reporting knee joint symptoms, severity of knee joint symptoms and duration of knee joint symptoms were twice as high for respondents with GJHk and KJH. Respondents with GJHk and KJH reported lower HRQoL. GJHk and KJH were frequently reported in the Danish adult population, mostly in women. Respondents with GJHk and KJH were two times more likely to report knee joint-related symptoms such as pain, reduced performance of usual activity and lower HRQoL. The impact of these conditions on HRQoL is comparable with knee osteoarthritis. © 2017 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.

Evaluation of Margins of Safety in Brazed Joints

NASA Technical Reports Server (NTRS)

Flom, Yury; Wang, Len; Powell, Mollie M.; Soffa, Matthew A.; Rommel, Monica L.

2009-01-01

One of the essential steps in assuring reliable performance of high cost critical brazed structures is the assessment of the Margin of Safety (MS) of the brazed joints. In many cases the experimental determination of the failure loads by destructive testing of the brazed assembly is not practical and cost prohibitive. In such cases the evaluation of the MS is performed analytically by comparing the maximum design loads with the allowable ones and incorporating various safety or knock down factors imposed by the customer. Unfortunately, an industry standard methodology for the design and analysis of brazed joints has not been developed. This paper provides an example of an approach that was used to analyze an AlBeMet 162 (38%Be-62%Al) structure brazed with the AWS BAlSi-4 (Al-12%Si) filler metal. A practical and conservative interaction equation combining shear and tensile allowables was developed and validated to evaluate an acceptable (safe) combination of tensile and shear stresses acting in the brazed joint. These allowables are obtained from testing of standard tensile and lap shear brazed specimens. The proposed equation enables the assessment of the load carrying capability of complex brazed joints subjected to multi-axial loading.

Model-Based Estimation of Ankle Joint Stiffness

PubMed Central

Misgeld, Berno J. E.; Zhang, Tony; Lüken, Markus J.; Leonhardt, Steffen

2017-01-01

We address the estimation of biomechanical parameters with wearable measurement technologies. In particular, we focus on the estimation of sagittal plane ankle joint stiffness in dorsiflexion/plantar flexion. For this estimation, a novel nonlinear biomechanical model of the lower leg was formulated that is driven by electromyographic signals. The model incorporates a two-dimensional kinematic description in the sagittal plane for the calculation of muscle lever arms and torques. To reduce estimation errors due to model uncertainties, a filtering algorithm is necessary that employs segmental orientation sensor measurements. Because of the model’s inherent nonlinearities and nonsmooth dynamics, a square-root cubature Kalman filter was developed. The performance of the novel estimation approach was evaluated in silico and in an experimental procedure. The experimental study was conducted with body-worn sensors and a test-bench that was specifically designed to obtain reference angle and torque measurements for a single joint. Results show that the filter is able to reconstruct joint angle positions, velocities and torque, as well as, joint stiffness during experimental test bench movements. PMID:28353683

Critical joints in large composite aircraft structure

NASA Technical Reports Server (NTRS)

Nelson, W. D.; Bunin, B. L.; Hart-Smith, L. J.

1983-01-01

A program was conducted at Douglas Aircraft Company to develop the technology for critical structural joints of composite wing structure that meets design requirements for a 1990 commercial transport aircraft. The prime objective of the program was to demonstrate the ability to reliably predict the strength of large bolted composite joints. Ancillary testing of 180 specimens generated data on strength and load-deflection characteristics which provided input to the joint analysis. Load-sharing between fasteners in multirow bolted joints was computed by the nonlinear analysis program A4EJ. This program was used to predict strengths of 20 additional large subcomponents representing strips from a wing root chordwise splice. In most cases, the predictions were accurate to within a few percent of the test results. In some cases, the observed mode of failure was different than anticipated. The highlight of the subcomponent testing was the consistent ability to achieve gross-section failure strains close to 0.005. That represents a considerable improvement over the state of the art.

Space station rotary joint mechanisms

NASA Technical Reports Server (NTRS)

Driskill, Glen W.

1986-01-01

The mechanism which will be used on the space station to position the solar arrays and radiator panels for Sun pointing and Sun avoidance is described. The unique design features will be demonstrated on advanced development models of two of the joints being fabricated under contract to NASA-MSFC.

The influence of patellofemoral joint contact geometry on the modeling of three dimensional patellofemoral joint forces.

PubMed

Powers, Christopher M; Chen, Yu-Jen; Scher, Irving; Lee, Thay Q

2006-01-01

The purpose of this study was to determine the influence of patellofemoral joint contact geometry on the modeling of three-dimensional patellofemoral joint forces. To achieve this goal, patellofemoral joint reaction forces (PFJRFs) that were measured from an in-vitro cadaveric set-up were compared to PFJRFs estimated from a computer model that did not consider patellofemoral joint contact geometry. Ten cadaver knees were used in this study. Each was mounted on a custom jig that was fixed to an Instron frame. Quadriceps muscle loads were accomplished using a pulley system and weights. The force in the patellar ligament was obtained using a buckle transducer. To quantify the magnitude and direction of the PFJRF, a six-axis load cell was incorporated into the femoral fixation system so that a rigid body assumption could be made. PFJRF data were obtained at 0 degrees , 20 degrees , 40 degrees and 60 degrees of knee flexion. Following in vitro testing, SIMM modeling software was used to develop computational models based on the three-dimensional coordinates (Microscribe digitizer) of individual muscle and patellar ligament force vectors obtained from the cadaver knees. The overall magnitude of the PFJRF estimated from the computer generated models closely matched the direct measurements from the in vitro set-up (Pearson's correlation coefficient, R(2)=0.91, p<0.001). Although the computational model accurately estimated the posteriorly directed forces acting on the joint, some discrepancies were noted in the forces acting in the superior and lateral directions. These differences however, were relatively small when expressed as a total of the overall PFJRF magnitude.

Shear Model Development of Limestone Joints with Incorporating Variations of Basic Friction Coefficient and Roughness Components During Shearing

NASA Astrophysics Data System (ADS)

Mehrishal, Seyedahmad; Sharifzadeh, Mostafa; Shahriar, Korosh; Song, Jae-Jon

2017-04-01

In relation to the shearing of rock joints, the precise and continuous evaluation of asperity interlocking, dilation, and basic friction properties has been the most important task in the modeling of shear strength. In this paper, in order to investigate these controlling factors, two types of limestone joint samples were prepared and CNL direct shear tests were performed on these joints under various shear conditions. One set of samples were travertine and another were onyx marble with slickensided surfaces, surfaces ground to #80, and rough surfaces were tested. Direct shear experiments conducted on slickensided and ground surfaces of limestone indicated that by increasing the applied normal stress, under different shearing rates, the basic friction coefficient decreased. Moreover, in the shear tests under constant normal stress and shearing rate, the basic friction coefficient remained constant for the different contact sizes. The second series of direct shear experiments in this research was conducted on tension joint samples to evaluate the effect of surface roughness on the shear behavior of the rough joints. This paper deals with the dilation and roughness interlocking using a method that characterizes the surface roughness of the joint based on a fundamental combined surface roughness concept. The application of stress-dependent basic friction and quantitative roughness parameters in the continuous modeling of the shear behavior of rock joints is an important aspect of this research.

The Interface of Mechanics and Nociception in Joint Pathophysiology: Insights From the Facet and Temporomandibular Joints

PubMed Central

Sperry, Megan M.; Ita, Meagan E.; Kartha, Sonia; Zhang, Sijia; Yu, Ya-Hsin; Winkelstein, Beth

2017-01-01

Chronic joint pain is a widespread problem that frequently occurs with aging and trauma. Pain occurs most often in synovial joints, the body's load bearing joints. The mechanical and molecular mechanisms contributing to synovial joint pain are reviewed using two examples, the cervical spinal facet joints and the temporomandibular joint (TMJ). Although much work has focused on the macroscale mechanics of joints in health and disease, the combined influence of tissue mechanics, molecular processes, and nociception in joint pain has only recently become a focus. Trauma and repeated loading can induce structural and biochemical changes in joints, altering their microenvironment and modifying the biomechanics of their constitutive tissues, which themselves are innervated. Peripheral pain sensors can become activated in response to changes in the joint microenvironment and relay pain signals to the spinal cord and brain where pain is processed and perceived. In some cases, pain circuitry is permanently changed, which may be a potential mechanism for sustained joint pain. However, it is most likely that alterations in both the joint microenvironment and the central nervous system (CNS) contribute to chronic pain. As such, the challenge of treating joint pain and degeneration is temporally and spatially complicated. This review summarizes anatomy, physiology, and pathophysiology of these joints and the sensory pain relays. Pain pathways are postulated to be sensitized by many factors, including degeneration and biochemical priming, with effects on thresholds for mechanical injury and/or dysfunction. Initiators of joint pain are discussed in the context of clinical challenges including the diagnosis and treatment of pain. PMID:28056123

Strength Variation of Parachute Joints

NASA Technical Reports Server (NTRS)

Mollmann, Catherine

2017-01-01

A parachute joint is defined as a location where a component is sewn or connected to another component. During the design and developmental phase of a parachute system, the joints for each structural component are isolated and tested through a process called seam and joint testing. The objective of seam and joint testing is to determine the degradation on a single component due to interaction with other components; this data is then used when calculating the margin of safety for that component. During the engineering developmental phase of CPAS (Capsule Parachute Assembly System), the parachute system for the NASA Orion Crew Module, testing was completed for every joint of the six subsystems: the four parachutes (main, drogue, pilot, and FBCP [forward bay cover parachute]), the retention release bridle, and the retention panels. The number of joint tests for these subsystems totaled 92, which provides a plethora of data and results for further analysis. In this paper, the data and results of these seam and joint tests are examined to determine the effects, if any, of different operators and sewing machines on the strength of parachute joints. Other variables are also studied to determine their effect on joint strength, such as joint complexity, joint strength magnitude, material type, and material construction. Findings reveal that an optimally-run seam and joint test program could result in an increased understanding of the structure of the parachute; this should lead to a parachute built with optimal components, potentially saving system weight and volume.

Running in ostriches (Struthio camelus): three-dimensional joint axes alignment and joint kinematics.

PubMed

Rubenson, Jonas; Lloyd, David G; Besier, Thor F; Heliams, Denham B; Fournier, Paul A

2007-07-01

Although locomotor kinematics in walking and running birds have been examined in studies exploring many biological aspects of bipedalism, these studies have been largely limited to two-dimensional analyses. Incorporating a five-segment, 17 degree-of-freedom (d.f.) kinematic model of the ostrich hind limb developed from anatomical specimens, we quantified the three-dimensional (3-D) joint axis alignment and joint kinematics during running (at approximately 3.3 m s(-1)) in the largest avian biped, the ostrich. Our analysis revealed that the majority of the segment motion during running in the ostrich occurs in flexion/extension. Importantly, however, the alignment of the average flexion/extension helical axes of the knee and ankle are rotated externally to the direction of travel (37 degrees and 21 degrees , respectively) so that pure flexion and extension at the knee will act to adduct and adbuct the tibiotarsus relative to the plane of movement, and pure flexion and extension at the ankle will act to abduct and adduct the tarsometatarsus relative to the plane of movement. This feature of the limb anatomy appears to provide the major lateral (non-sagittal) displacement of the lower limb necessary for steering the swinging limb clear of the stance limb and replaces what would otherwise require greater adduction/abduction and/or internal/external rotation, allowing for less complex joints, musculoskeletal geometry and neuromuscular control. Significant rotation about the joints' non-flexion/extension axes nevertheless occurs over the running stride. In particular, hip abduction and knee internal/external and varus/valgus motion may further facilitate limb clearance during the swing phase, and substantial non-flexion/extension movement at the knee is also observed during stance. Measurement of 3-D segment and joint motion in birds will be aided by the use of functionally determined axes of rotation rather than assumed axes, proving important when interpreting the

Development of an Intelligent Stretching Device for Ankle Joints With Contracture/Spasticity

DTIC Science & Technology

2001-10-25

percentage corresponded to background dorsi-flexion muscle contraction and 0% was the relaxed state. Next, tendon reflexes were evaluated...the representative cases, joint stiffness was reduced markedly after stretching across the range of muscle contraction (Fig. 5), including both

Intraoperative Considerations for Treatment/Prevention of Prosthetic Joint Infection.

PubMed

Suleiman, Linda I; Mesko, Daniel R; Nam, Denis

2018-06-23

Innovative measures have recently been proposed to prevent periprosthetic joint infection following total hip and knee arthroplasty. We sought to review these recent innovations to determine the reported reduction in periprosthetic joint infection. The most recent literature demonstrates promising results in regard to hydrofiber dressings as an independent risk factor for primary prosthetic joint infection reduction, which in turn is also linked with cost savings. As our understanding of safe yet effective concentrations of antiseptic solutions develops, dilute betadine in particular has demonstrated encouraging efficacy which warrants continued investigation through controlled trials. In summary, we found that the application of a hydrofiber dressing may prove beneficial in decreasing the risk of prosthetic joint infection following primary total hip and knee arthroplasty. The gold standard for an infection prevention protocol continues to be explored and optimized.

Ability of finger-jointed lumber to maintain load at elevated temperatures

Treesearch

Douglas R. Rammer; Samuel L. Zelinka; Laura E Hasburgh; Steven T. Craft

2018-01-01

This article presents a test method that was developed to screen adhesive formulations for finger-jointed lumber. The goal was to develop a small-scale test that could be used to predict whether an adhesive would pass a full-scale ASTM E119 wall assembly test. The method involved loading a 38-mm square finger-jointed sample in a four-point bending test inside of an...

Joint Enrollment Report, 2014

ERIC Educational Resources Information Center

Iowa Department of Education, 2014

2014-01-01

The Iowa Department of Education collects information on joint enrollment in Iowa's 15 community colleges. Jointly enrolled students are high school students enrolled in community college credit coursework. Most jointly enrolled students enroll through Senior Year Plus (SYP) programs such as Postsecondary Enrollment Options (PSEO) and concurrent…

Joint Enrollment Report, 2015

ERIC Educational Resources Information Center

Iowa Department of Education, 2015

2015-01-01

The Iowa Department of Education collects information on joint enrollment from Iowa's 15 community colleges. Jointly enrolled students are high school students enrolled in community college credit coursework. Most jointly enrolled students enroll through Senior Year Plus programs such as Postsecondary Enrollment Options (PSEO) and concurrent…

Three-dimensional reconstruction of rat knee joint using episcopic fluorescence image capture.

PubMed

Takaishi, R; Aoyama, T; Zhang, X; Higuchi, S; Yamada, S; Takakuwa, T

2014-10-01

Development of the knee joint was morphologically investigated, and the process of cavitation was analyzed by using episcopic fluorescence image capture (EFIC) to create spatial and temporal three-dimensional (3D) reconstructions. Knee joints of Wister rat embryos between embryonic day (E)14 and E20 were investigated. Samples were sectioned and visualized using an EFIC. Then, two-dimensional image stacks were reconstructed using OsiriX software, and 3D reconstructions were generated using Amira software. Cavitations of the knee joint were constructed from five divided portions. Cavity formation initiated at multiple sites at E17; among them, the femoropatellar cavity (FPC) was the first. Cavitations of the medial side preceded those of the lateral side. Each cavity connected at E20 when cavitations around the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) were completed. Cavity formation initiated from six portions. In each portion, development proceeded asymmetrically. These results concerning anatomical development of the knee joint using EFIC contribute to a better understanding of the structural feature of the knee joint. Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

FE analysis of SMA-based bio-inspired bone-joint system

NASA Astrophysics Data System (ADS)

Yang, S.; Seelecke, S.

2009-10-01

This paper presents the finite element (FE) analysis of a bio-inspired bone-joint system. Motivated by the BATMAV project, which aims at the development of a micro-air-vehicle platform that implements bat-like flapping flight capabilities, we study the actuation of a typical elbow joint, using shape memory alloy (SMA) in a dual manner. Micro-scale martensitic SMA wires are used as 'metal muscles' to actuate a system of humerus, elbow joint and radius, in concert with austenitic wires, which operate as flexible joints due to their superelastic character. For the FE analysis, the humerus and radius are modeled as standard elastic beams, while the elbow joint and muscle wires use the Achenbach-Muller-Seelecke SMA model as beams and cable elements, respectively. The particular focus of the paper is on the implementation of the above SMA model in COMSOL.

Migrating lumbar facet joint cysts.

PubMed

Palmieri, Francesco; Cassar-Pullicino, Victor N; Lalam, Radhesh K; Tins, Bernhard J; Tyrrell, Prudencia N M; McCall, Iain W

2006-04-01

The majority of lumbar facet joint cysts (LFJCs) are located in the spinal canal, on the medial aspect of the facet joint with characteristic diagnostic features. When they migrate away from the joint of origin, they cause diagnostic problems. In a 7-year period we examined by computed tomography (CT) and magnetic resonance (MR) imaging five unusual cases of facet joint cysts which migrated from the facet joint of origin. Three LFJCs were identified in the right S1 foramen, one in the right L5-S1 neural foramen and one in the left erector spinae and multifidus muscles between the levels of L2-L4 spinous process. Awareness that spinal lesions identified at MRI and CT could be due to migrating facet joint cyst requires a high level of suspicion. The identification of the appositional contact of the cyst and the facet joint needs to be actively sought in the presence of degenerative facet joints.

P2X3 and P2X2/3 Receptors Play a Crucial Role in Articular Hyperalgesia Development Through Inflammatory Mechanisms in the Knee Joint Experimental Synovitis.

PubMed

Teixeira, Juliana Maia; Bobinski, Franciane; Parada, Carlos Amílcar; Sluka, Kathleen A; Tambeli, Cláudia Herrera

2017-10-01

Osteoarthritis (OA) is a degenerative and progressive disease characterized by cartilage breakdown and by synovial membrane inflammation, which results in disability, joint swelling, and pain. The purinergic P2X3 and P2X2/3 receptors contribute to development of inflammatory hyperalgesia, participate in arthritis processes in the knee joint, and are expressed in chondrocytes and nociceptive afferent fibers innervating the knee joint. In this study, we hypothesized that P2X3 and P2X2/3 receptors activation by endogenous ATP (adenosine 5'-triphosphate) induces articular hyperalgesia in the knee joint of male and female rats through an indirect sensitization of primary afferent nociceptors dependent on the previous release of pro-inflammatory cytokines and/or on neutrophil migration. We found that the blockade of articular P2X3 and P2X2/3 receptors significantly attenuated carrageenan-induced hyperalgesia in the knee joint of male and estrus female rats in a similar manner. The carrageenan-induced knee joint inflammation increased the expression of P2X3 receptors in chondrocytes of articular cartilage. Further, the blockade of articular P2X3 and P2X2/3 receptors significantly reduced the increased concentration of TNF-α, IL-6, and CINC-1 and the neutrophil migration induced by carrageenan. These findings indicate that P2X3 and P2X2/3 receptors activation by endogenous ATP is essential to hyperalgesia development in the knee joint through an indirect sensitization of primary afferent nociceptors dependent on the previous release of pro-inflammatory cytokines and/or on neutrophil migration.

Systems engineering in a joint program environment: the joint helmet-mounted cueing system

NASA Astrophysics Data System (ADS)

Wilkins, Donald F.

1999-07-01

The Joint Helmet Mounted Cueing System (JHMCS) is a design program involving two airframe companies (Boeing and Lockheed Martin), two services (USAF and USN) and four aircraft platforms: the F-22, the F-16, the F/A-18 and the F-15. Developing equipment requirements for the combined operational and environmental needs of these diverse communities is a significant challenge. In addition, the team is geographically dispersed which presented challenges in communication and coordination. This paper details the lessons learned in producing a cost-effective design within a short development schedule and makes recommendations for future development programs.

Culture - joint fluid

MedlinePlus

... this page: //medlineplus.gov/ency/article/003742.htm Culture - joint fluid To use the sharing features on this page, please enable JavaScript. Joint fluid culture is a laboratory test to detect infection-causing ...

Joint Chiefs of Staff > About > Joint Staff Inspector General

Science.gov Websites

DD Form 2949, Joint Inspector General Action Request (available at the link below). However, if you action if you intentionally make false statements. When you sign a DD Form 2949, you are signing a . DD Form 2949, Joint Inspector General Action Request Click here to expand content Click here to

Ceramic joints

DOEpatents

Miller, Bradley J.; Patten, Jr., Donald O.

1991-01-01

Butt joints between materials having different coefficients of thermal expansion are prepared having a reduced probability of failure of stress facture. This is accomplished by narrowing/tapering the material having the lower coefficient of thermal expansion in a direction away from the joint interface and not joining the narrow-tapered surface to the material having the higher coefficient of thermal expansion.

Sacroiliac joint dysfunction.

PubMed

Ilaslan, Hakan; Arslan, Ahmet; Koç, Omer Nadir; Dalkiliç, Turker; Naderi, Sait

2010-07-01

Sacroiliac joint dysfunction is a disorder presenting with low back and groin pain. It should be taken into consideration during the preoperative differential diagnosis of lumbar disc herniation, lumbar spinal stenosis and facet syndrome. Four cases with sacroiliac dysfunction are presented. The clinical and radiological signs supported the evidence of sacroiliac dysfunction, and exact diagnosis was made after positive response to sacroiliac joint block. A percutaneous sacroiliac fixation provided pain relief in all cases. The mean VAS scores reduced from 8.2 to 2.2. It is concluded that sacroiliac joint dysfunction diagnosis requires a careful physical examination of the sacroiliac joints in all cases with low back and groin pain. The diagnosis is made based on positive response to the sacroiliac block. Sacroiliac fixation was found to be effective in carefully selected cases.

Model-based sensorimotor integration for multi-joint control: development of a virtual arm model.

PubMed

Song, D; Lan, N; Loeb, G E; Gordon, J

2008-06-01

An integrated, sensorimotor virtual arm (VA) model has been developed and validated for simulation studies of control of human arm movements. Realistic anatomical features of shoulder, elbow and forearm joints were captured with a graphic modeling environment, SIMM. The model included 15 musculotendon elements acting at the shoulder, elbow and forearm. Muscle actions on joints were evaluated by SIMM generated moment arms that were matched to experimentally measured profiles. The Virtual Muscle (VM) model contained appropriate admixture of slow and fast twitch fibers with realistic physiological properties for force production. A realistic spindle model was embedded in each VM with inputs of fascicle length, gamma static (gamma(stat)) and dynamic (gamma(dyn)) controls and outputs of primary (I(a)) and secondary (II) afferents. A piecewise linear model of Golgi Tendon Organ (GTO) represented the ensemble sampling (I(b)) of the total muscle force at the tendon. All model components were integrated into a Simulink block using a special software tool. The complete VA model was validated with open-loop simulation at discrete hand positions within the full range of alpha and gamma drives to extrafusal and intrafusal muscle fibers. The model behaviors were consistent with a wide variety of physiological phenomena. Spindle afferents were effectively modulated by fusimotor drives and hand positions of the arm. These simulations validated the VA model as a computational tool for studying arm movement control. The VA model is available to researchers at website http://pt.usc.edu/cel .

Cytokine mRNA expression in synovial fluid of affected and contralateral stifle joints and the left shoulder joint in dogs with unilateral disease of the stifle joint.

PubMed

de Bruin, Tanya; de Rooster, Hilde; van Bree, Henri; Duchateau, Luc; Cox, Eric

2007-09-01

To examine mRNA expression of cytokines in synovial fluid (SF) cells from dogs with cranial cruciate ligament (CrCL) rupture and medial patellar luxation (MPL) and determine mRNA expression for 3 joints (affected stifle, unaffected contralateral stifle, and left shoulder joints) in dogs with unilateral CrCL rupture. 29 stifle joints with CrCL rupture (29 dogs), 8 stifle joints with MPL (7 dogs), and 24 normal stifle joints (16 clinically normal dogs). Immediately before reconstructive surgery, SF was aspirated from the cruciate-deficient stifle joint or stifle joint with MPL. Fourteen of 29 dogs had unilateral CrCL rupture; SF was also aspirated from the unaffected contralateral stifle joint and left shoulder joint. Those 14 dogs were examined 6 and 12 months after reconstructive surgery. Total RNA was extracted from SF cells and reverse transcription-PCR assay was performed to obtain cDNA. Canine-specific cytokine mRNA expression was determined by use of a real-time PCR assay. Interleukin (IL)-8 and -10 and interferon-gamma expression differed significantly between dogs with arthropathies and dogs with normal stifle joints. For the 14 dogs with unilateral CrCL rupture, a significant difference was found for IL-8 expression. Before reconstructive surgery, IL-8 expression differed significantly between the affected stifle joint and left shoulder joint or contralateral stifle joint. Six months after surgery, IL-8 expression was significantly increased in the unaffected contralateral stifle joint, compared with the shoulder joint. No conclusions can be made regarding the role of the examined cytokines in initiation of CrCL disease.

Hip joint injection

MedlinePlus

... medicine into the joint. The provider uses a real-time x-ray (fluoroscopy) to see where to place ... Wakefield RJ. Arthrocentesis and injection of joints and soft tissue. In: Firestein GS, Budd RC, Gabriel SE, ...

Some ways in which neighborhoods, nuclear families, friendship groups, and schools jointly affect changes in early adolescent development.

PubMed

Cook, Thomas D; Herman, Melissa R; Phillips, Meredith; Settersten, Richard A

2002-01-01

This study assessed some ways in which schools, neighborhoods, nuclear families, and friendship groups jointly contribute to positive change during early adolescence. For each context, existing theory was used to develop a multiattribute index that should promote successful development. Descriptive analyses showed that the four resulting context indices were only modestly intercorrelated at the individual student level (N = 12,398), but clustered more tightly at the school and neighborhood levels (N = 23 and 151 respectively). Only for aggregated units did knowing the developmental capacity of any one context strongly predict the corresponding capacity of the other contexts. Analyses also revealed that each context facilitated individual change in a success index that tapped into student academic performance, mental health, and social behavior. However, individual context effects were only modest in size over the 19 months studied and did not vary much by context. The joint influence of all four contexts was cumulatively large, however, and because it was generally additive in form, no constellation of contexts was identified whose total effect reliably surpassed the sum of its individual context main effects. These results suggest that achieving significant population changes in multidimensional student growth during early adolescence most likely requires both theory and interventions that are explicitly pan-contextual.

Joint attention studies in normal and autistic children using NIRS

NASA Astrophysics Data System (ADS)

Chaudhary, Ujwal; Hall, Michael; Gutierrez, Anibal; Messinger, Daniel; Rey, Gustavo; Godavarty, Anuradha

2011-03-01

Autism is a socio-communication brain development disorder. It is marked by degeneration in the ability to respond to joint attention skill task, from as early as 12 to 18 months of age. This trait is used to distinguish autistic from nonautistic. In this study Near infrared spectroscopy (NIRS) is being applied for the first time to study the difference in activation and connectivity in the frontal cortex of typically developing (TD) and autistic children between 4-8 years of age in response to joint attention task. The optical measurements are acquired in real time from frontal cortex using Imagent (ISS Inc.) - a frequency domain based NIRS system in response to video clips which engenders a feeling of joint attention experience in the subjects. A block design consisting of 5 blocks of following sequence 30 sec joint attention clip (J), 30 sec non-joint attention clip (NJ) and 30 sec rest condition is used. Preliminary results from TD child shows difference in brain activation (in terms of oxy-hemoglobin, HbO) during joint attention interaction compared to the nonjoint interaction and rest. Similar activation study did not reveal significant differences in HbO across the stimuli in, unlike in an autistic child. Extensive studies are carried out to validate the initial observations from both brain activation as well as connectivity analysis. The result has significant implication for research in neural pathways associated with autism that can be mapped using NIRS.

Stress analysis of bolted joints under centrifugal force

NASA Astrophysics Data System (ADS)

Imura, Makoto; Iizuka, Motonobu; Nakae, Shigeki; Mori, Takeshi; Koyama, Takayuki

2014-06-01

Our objective is to develop a long-life rotary machine for synchronous generators and motors. To do this, it is necessary to design a high-strength bolted joint, which is responsible for fixing a salient pole on a rotor shaft. While the rotary machine is in operation, not only centrifugal force but also moment are loaded on a bolted joint, because a point of load is eccentric to a centre of a bolt. We tried to apply the theory proposed in VDI2230-Blatt1 to evaluate the bolted joint under eccentric force, estimate limited centrifugal force, which is the cause of partial separation between the pole and the rotor shaft, and then evaluate additional tension of a bolt after the partial separation has occurred. We analyzed the bolted joint by FEM, and defined load introduction factor in that case. Additionally, we investigated the effect of the variation of bolt preload on the partial separation. We did a full scale experiment with a prototype rotor to reveal the variation of bolt preload against tightening torque. After that, we verified limited centrifugal force and the strength of the bolted joint by the VDI2230-Blatt1 theory and FEM considering the variation of bolt preload. Finally, we could design a high-strength bolted joint verified by the theoretical study and FEM analysis.

Radiating columnar joints in Gyeongju, Korea as a educational site

NASA Astrophysics Data System (ADS)

Woo, H.; Kim, J. H.; Jang, Y. D.

2015-12-01

Gyeongju is located in the central eastern part of South Korea. There are various directional columnar joint sets in Tertiary trachytic basalt formation along the shore. In particular, rare radiating columnar joints occur in this area. Columnar joints are parallel, prismatic columns that are formed as a result of contraction during the rapid cooling of lava flow, forming a three dimensional fracture network. In general, the radius and direction of the rock column represent the cooling rate and surface respectively. Radiating direction of columns here indicates that dome- or lobe-shaped lava was cooled from its surface to the core during the viscous lava flow. The fact that the trachytic textures of plagioclase laths are indistinct suggests that the radiating columnar joints are equivalent to the frontal end of the lava lobes. This area is currently has a shore trail course, which is being developed into a picturesque educational park. There are corresponding information boards on the trail near each type of columnar joints to explain not only the forming process and geological mechanisms but the importance of nature conservation to visitors, especially students. A variety of educational materials and educational programs linked to regular school curriculum are also being developed.

Description of and preliminary tests results for the Joint Damping Experiment (JDX)

NASA Technical Reports Server (NTRS)

Bingham, Jeffrey G.; Folkman, Steven L.

1995-01-01

An effort is currently underway to develop an experiment titled joint Damping E_periment (JDX) to fly on the Space Shuttle as Get Away Special Payload G-726. This project is funded by NASA's IN-Space Technology Experiments Program and is scheduled to fly in July 1995 on STS-69. JDX will measure the influence of gravity on the structural damping of a three bay truss having clearance fit pinned joints. Structural damping is an important parameter in the dynamics of space structures. Future space structures will require more precise knowledge of structural damping than is currently available. The mission objectives are to develop a small-scale shuttle flight experiment that allows researchers to: (1) characterize the influence of gravity and joint gaps on structural damping and dynamic behavior of a small-scale truss model, and (2) evaluate the applicability of low-g aircraft test results for predicting on-orbit behavior. Completing the above objectives will allow a better understanding and/or prediction of structural damping occurring in a pin jointed truss. Predicting damping in joints is quite difficult. One of the important variables influencing joint damping is gravity. Previous work has shown that gravity loads can influence damping in a pin jointed truss structure. Flying this experiment as a GAS payload will allow testing in a microgravity environment. The on-orbit data (in micro-gravity) will be compared with ground test results. These data will be used to help develop improved models to predict damping due to pinned joints. Ground and low-g aircraft testing of this experiment has been completed. This paper describes the experiment and presents results of both ground and low-g aircraft tests which demonstrate that damping of the truss is dramatically influenced by gravity.

Joint Aspiration (Arthrocentesis)

MedlinePlus

... arthritis, or JRA), systemic lupus erythematosus (SLE), and Lyme disease. Joint aspiration is diagnostic but it also can ... topic for: Parents Kids Teens Evaluate Your Child's Lyme Disease Risk Living With Lupus Bones, Muscles, and Joints ...

Longitudinal joint study.

DOT National Transportation Integrated Search

2001-09-01

In previous years there has been a problem with longitudinal joint : deterioration, due in part to poor construction techniques. : The degradation of the longitudinal joints has increased the cost of : maintaining these projects and caused unnecessar...

An in vitro simulation method for the tribological assessment of complete natural hip joints

PubMed Central

Fisher, John; Williams, Sophie

2017-01-01

The use of hip joint simulators to evaluate the tribological performance of total hip replacements is widely reported in the literature, however, in vitro simulation studies investigating the tribology of the natural hip joint are limited with heterogeneous methodologies reported. An in vitro simulation system for the complete natural hip joint, enabling the acetabulum and femoral head to be positioned with different orientations whilst maintaining the correct joint centre of rotation, was successfully developed for this study. The efficacy of the simulation system was assessed by testing complete, matched natural porcine hip joints and porcine hip hemiarthroplasty joints in a pendulum friction simulator. The results showed evidence of biphasic lubrication, with a non-linear increase in friction being observed in both groups. Lower overall mean friction factor values in the complete natural joint group that increased at a lower rate over time, suggest that the exudation of fluid and transition to solid phase lubrication occurred more slowly in the complete natural hip joint compared to the hip hemiarthroplasty joint. It is envisaged that this methodology will be used to investigate morphological risk factors for developing hip osteoarthritis, as well as the effectiveness of early interventional treatments for degenerative hip disease. PMID:28886084

JANNAF 28th Propellant Development and Characterization Subcommittee and 17th Safety and Environmental Protection Subcommittee Joint Meeting. Volume 1

NASA Technical Reports Server (NTRS)

Cocchiaro, James E. (Editor); Mulder, Edwin J. (Editor); Gomez-Knight, Sylvia J. (Editor)

1999-01-01

This volume contains 37 unclassified/unlimited-distribution technical papers that were presented at the JANNAF 28th Propellant Development & Characterization Subcommittee (PDCS) and 17th Safety & Environmental Protection Subcommittee (S&EPS) Joint Meeting, held 26-30 April 1999 at the Town & Country Hotel and the Naval Submarine Base, San Diego, California. Volume II contains 29 unclassified/limited-distribution papers that were presented at the 28th PDCS and 17th S&EPS Joint Meeting. Volume III contains a classified paper that was presented at the 28th PDCS Meeting on 27 April 1999. Topics covered in PDCS sessions include: solid propellant rheology; solid propellant surveillance and aging; propellant process engineering; new solid propellant ingredients and formulation development; reduced toxicity liquid propellants; characterization of hypergolic propellants; and solid propellant chemical analysis methods. Topics covered in S&EPS sessions include: space launch range safety; liquid propellant hazards; vapor detection methods for toxic propellant vapors and other hazardous gases; toxicity of propellants, ingredients, and propellant combustion products; personal protective equipment for toxic liquid propellants; and demilitarization/treatment of energetic material wastes.

Transforming Joint Warfighting Capabilities

DTIC Science & Technology

2004-01-01

Certification guidance covers Internet or Web compatibility and the layout to include window size, color, typography , and graphic format. Further require...developed the JMF concept, defined as a package of 20,000 personnel from designated component ready forces. It is aug- mented by supporting commands...trust and confidence in joint warfighting. PACOM established standing com- mand and control relationships for cri- sis response by designating primary

Joint Control for Dummies: An Elaboration of Lowenkron's Model of Joint (Stimulus) Control

ERIC Educational Resources Information Center

Sidener, David W.

2006-01-01

The following paper describes Lowenkron's model of joint (stimulus) control. Joint control is described as a means of accounting for performances, especially generalized performances, for which a history of contingency control does not provide an adequate account. Examples are provided to illustrate instances in which joint control may facilitate…

Agriculture and Community Development Interface. Joint Meeting of the Southern Region State Leaders for Agriculture and Natural Resources and Community Resource Development Proceedings (October 8-11, 1989, Williamsburg, Virginia).

ERIC Educational Resources Information Center

Warner, Paul D., Ed.; Campbell, Raymond, Ed.

This document is a summary of remarks presented at a joint meeting of Agriculture and Natural Resources and Community Resource Development state leaders in 1989. The focus of the meeting was economic viability, rural extension and education, water quality, waste management, biotechnology, low-input sustainable agriculture (LISA), and rural…

What It Takes. Air Force Command of Joint Operations

DTIC Science & Technology

2009-01-01

Iraq Assistance Group IDE intermediate developmental education IO international organization ISAF International Security and Assistance Force ISR...Operations Table A.1—Continued Joint Task Force Mission/Operation Start End Service Command Rank JTF–Joint Area Support Group (JASG) Iraqi Freedom...be of interest to a wide group of Air Force personnel involved in the development and func- tion of the service’s command organizations, including

Prevention of the Post-traumatic Fibrotic Response in Joints

DTIC Science & Technology

2014-10-01

an experimental model in mice. The American journal of forensic medicine and pathology . 1988; 9(4):310-2. 14 APPENDICES: An abstract...ongoing study addresses the critical clinical problem of posttraumatic joint stiffness, a pathology that reduces the range of motion (ROM) of injured...joints and contributes to the development of osteoarthritis. The fundamental hypothesis that drives the current study is that pathological fibrotic

Simulation of in vivo dynamics during robot assisted joint movement.

PubMed

Bobrowitsch, Evgenij; Lorenz, Andrea; Wülker, Nikolaus; Walter, Christian

2014-12-16

Robots are very useful tools in orthopedic research. They can provide force/torque controlled specimen motion with high repeatability and precision. A method to analyze dissipative energy outcome in an entire joint was developed in our group. In a previous study, a sheep knee was flexed while axial load remained constant during the measurement of dissipated energy. We intend to apply this method for the investigation of osteoarthritis. Additionally, the method should be improved by simulation of in vivo knee dynamics. Thus, a new biomechanical testing tool will be developed for analyzing in vitro joint properties after different treatments. Discretization of passive knee flexion was used to construct a complex flexion movement by a robot and simulate altering axial load similar to in vivo sheep knee dynamics described in a previous experimental study. The robot applied an in vivo like axial force profile with high reproducibility during the corresponding knee flexion (total standard deviation of 0.025 body weight (BW)). A total residual error between the in vivo and simulated axial force was 0.16 BW. Posterior-anterior and medio-lateral forces were detected by the robot as a backlash of joint structures. Their curve forms were similar to curve forms of corresponding in vivo measured forces, but in contrast to the axial force, they showed higher total standard deviation of 0.118 and 0.203 BW and higher total residual error of 0.79 and 0.21 BW for posterior-anterior and medio-lateral forces respectively. We developed and evaluated an algorithm for the robotic simulation of complex in vivo joint dynamics using a joint specimen. This should be a new biomechanical testing tool for analyzing joint properties after different treatments.

Infant Joint Attention, Temperament, and Social Competence in Preschool Children

ERIC Educational Resources Information Center

Vaughan Van Hecke, Amy; Mundy, Peter C.; Acra, C. Francoise.; Block, Jessica J.; Delgado, Christine E. F.; Parlade, Meaghan V.; Meyer, Jessica A.; Neal, A. Rebecca; Pomares, Yuly B.

2007-01-01

Infant joint attention has been observed to be related to social-emotional outcomes in at-risk children. To address whether this relation is also evident in typically developing children, 52 children were tested at 12, 15, 24, and 30 months to examine associations between infant joint attention and social outcomes. Twelve-month initiating and…

Joint attention and oromotor abilities in young children with and without autism spectrum disorder.

PubMed

Dalton, Jennifer C; Crais, Elizabeth R; Velleman, Shelley L

2017-09-01

This study examined the relationship between joint attention ability and oromotor imitation skill in three groups of young children with and without Autism Spectrum Disorder using both nonverbal oral and verbal motor imitation tasks. Research questions addressed a) differences among joint attention and oromotor imitation abilities; b) the relationship between independently measured joint attention and oromotor imitation, both nonverbal oral and verbal motor; c) the relationships between joint attention and verbal motor imitation during interpersonal interaction; and d) the relationship between the sensory input demands (auditory, visual, and tactile) and oromotor imitation, both nonverbal oral and verbal motor. A descriptive, nonexperimental design was used to compare joint attention and oromotor skills of 10 preschool-aged children with ASD, with those of two control groups: 6 typically developing children (TD), and 6 children with suspected Childhood Apraxia of Speech (sCAS) or apraxic-like symptoms. All children had at least a 3.0 mean length utterance. Children with ASD had poorer joint attention skills overall than children with sCAS or typically developing children. Typically developing children demonstrated higher verbal motor imitation skills overall compared to children with sCAS. Correlational analyses revealed that nonverbal oral imitation and verbal motor imitation were positively related to joint attention abilities only in the children with ASD. Strong positive relationships between joint attention in a naturalistic context (e.g., shared story experience) and oromotor imitation skills, both nonverbal oral and verbal motor, were found only for children with ASD. These data suggest there is a strong positive relationship between joint attention skills and the ability to sequence nonverbal oral and verbal motor movements in children with ASD. The combined sensory input approach involving auditory, visual, and tactile modalities contributed to

High pressure ceramic joint

DOEpatents

Ward, Michael E.; Harkins, Bruce D.

1993-01-01

Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present joint when used with recuperators increases the use of ceramic components which do not react to highly corrosive gases. Thus, the present joint used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present joint is comprised of a first ceramic member, a second ceramic member, a mechanical locking device having a groove defined in one of the first ceramic member and the second ceramic member. The joint and the mechanical locking device is further comprised of a refractory material disposed in the groove and contacting the first ceramic member and the second ceramic member. The present joint mechanically provides a high strength load bearing joint having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

Comparison of the use of notched wedge joints vs. traditional butt joints in Connecticut

DOT National Transportation Integrated Search

2008-11-07

Performance of Hot Mix Asphalt (HMA) longitudinal joints have been an item of increasing scrutiny in : Connecticut. The traditional butt joint has typically been the method used in Connecticut. These joints : have been reportedly opening up, creating...

Adhesive Characterization and Progressive Damage Analysis of Bonded Composite Joints

NASA Technical Reports Server (NTRS)

Girolamo, Donato; Davila, Carlos G.; Leone, Frank A.; Lin, Shih-Yung

2014-01-01

The results of an experimental/numerical campaign aimed to develop progressive damage analysis (PDA) tools for predicting the strength of a composite bonded joint under tensile loads are presented. The PDA is based on continuum damage mechanics (CDM) to account for intralaminar damage, and cohesive laws to account for interlaminar and adhesive damage. The adhesive response is characterized using standard fracture specimens and digital image correlation (DIC). The displacement fields measured by DIC are used to calculate the J-integrals, from which the associated cohesive laws of the structural adhesive can be derived. A finite element model of a sandwich conventional splice joint (CSJ) under tensile loads was developed. The simulations indicate that the model is capable of predicting the interactions of damage modes that lead to the failure of the joint.

The joint Simon effect: a review and theoretical integration

PubMed Central

Dolk, Thomas; Hommel, Bernhard; Colzato, Lorenza S.; Schütz-Bosbach, Simone; Prinz, Wolfgang; Liepelt, Roman

2014-01-01

The social or joint Simon effect has been developed to investigate how and to what extent people mentally represent their own and other persons' action/task and how these cognitive representations influence an individual's own behavior when interacting with another person. Here, we provide a review of the available evidence and theoretical frameworks. Based on this review, we suggest a comprehensive theory that integrates aspects of earlier approaches–the Referential Coding Account. This account provides an alternative to the social interpretation of the (joint) go-nogo Simon effect (aka the social Simon effect) and is able to integrate seemingly opposite findings on joint action. PMID:25249991

1997 William J. Stickel Gold Award. Morphological and biochemical properties of metatarsophalangeal joint cartilage.

PubMed

Muehleman, C; Chubinskaya, S; Cole, A A; Noskina, Y; Arsenis, C; Kuettner, K E

1997-10-01

Although there is sparse information concerning the properties of foot-joint cartilages, knowledge of the morphology and biochemistry of these cartilages is important in the study of changes that occur in the development of osteoarthritis. Normal first and fifth metatarsophalangeal joints were chosen for comparison because of the difference between these two joints in the prevalence of osteoarthritis, particularly with advancing age. The authors' study shows that there is no age-related decrease in articular-cartilage thickness; however, there is an age-related decrease in the chondrocyte density in the superficial zone in both joints. There is, however, a difference between the two joints in the level of expression of matrix-degrading enzymes. This difference may indicate differences in specific chondrocyte activity that precedes or accompanies the development of osteoarthritis or other degenerative morphological changes.

Evaluation of narrow transverse contraction joints in jointed plain concrete pavements.

DOT National Transportation Integrated Search

2006-03-01

This report presents the results of a research project conducted at the Louisiana Transportation Research Center (LTRC) to evaluate the performance of narrow transverse contraction joints to control cracking in jointed plain concrete pavements. In ad...

Experimental Investigation of Composite Pressure Vessel Performance and Joint Stiffness for Pyramid and Inverted Pyramid Joints

NASA Technical Reports Server (NTRS)

Verhage, Joseph M.; Bower, Mark V.; Gilbert, Paul A. (Technical Monitor)

2001-01-01

The focus of this study is on the suitability in the application of classical laminate theory analysis tools for filament wound pressure vessels with adhesive laminated joints in particular: pressure vessel wall performance, joint stiffness and failure prediction. Two 18-inch diameter 12-ply filament wound pressure vessels were fabricated. One vessel was fabricated with a 24-ply pyramid laminated adhesive double strap butt joint. The second vessel was fabricated with the same number of plies in an inverted pyramid joint. Results from hydrostatic tests are presented. Experimental results were used as input to the computer programs GENLAM and Laminate, and the output compared to test. By using the axial stress resultant, the classical laminate theory results show a correlation within 1% to the experimental results in predicting the pressure vessel wall pressure performance. The prediction of joint stiffness for the two adhesive joints in the axial direction is within 1% of the experimental results. The calculated hoop direction joint stress resultant is 25% less than the measured resultant for both joint configurations. A correction factor is derived and used in the joint analysis. The correction factor is derived from the hoop stress resultant from the tank wall performance investigation. The vessel with the pyramid joint is determined to have failed in the joint area at a hydrostatic pressure 33% value below predicted failure. The vessel with the inverted pyramid joint failed in the wall acreage at a hydrostatic pressure within 10% of the actual failure pressure.

Longitudinal joint treatment.

DOT National Transportation Integrated Search

2006-03-01

Maine highways have been showing signs of longitudinal joint failure for a number of years. In an effort : to reduce the amount of joint failures the Maine Department of Transportation (MDOT) is currently : evaluating two projects. One project is mon...

Novel Ultrasound Joint Selection Methods Using a Reduced Joint Number Demonstrate Inflammatory Improvement when Compared to Existing Methods and Disease Activity Score at 28 Joints.

PubMed

Tan, York Kiat; Allen, John C; Lye, Weng Kit; Conaghan, Philip G; D'Agostino, Maria Antonietta; Chew, Li-Ching; Thumboo, Julian

2016-01-01

A pilot study testing novel ultrasound (US) joint-selection methods in rheumatoid arthritis. Responsiveness of novel [individualized US (IUS) and individualized composite US (ICUS)] methods were compared with existing US methods and the Disease Activity Score at 28 joints (DAS28) for 12 patients followed for 3 months. IUS selected up to 7 and 12 most ultrasonographically inflamed joints, while ICUS additionally incorporated clinically symptomatic joints. The existing, IUS, and ICUS methods' standardized response means were -0.39, -1.08, and -1.11, respectively, for 7 joints; -0.49, -1.00, and -1.16, respectively, for 12 joints; and -0.94 for DAS28. Novel methods effectively demonstrate inflammatory improvement when compared with existing methods and DAS28.

Anatomical study of the articular branches innervated the hip and knee joint with reference to mechanism of referral pain in hip joint disease patients.

PubMed

Sakamoto, Junya; Manabe, Yoshitaka; Oyamada, Joichi; Kataoka, Hideki; Nakano, Jiro; Saiki, Kazunobu; Okamoto, Keishi; Tsurumoto, Toshiyuki; Okita, Minoru

2018-07-01

Referred pain in the anterior knee joint is the most common symptom in hip disease patients. The development of referred pain is considered to be related to dichotomizing peripheral sensory fibers. However, no gross anatomical findings identify any dichotomizing fibers innervating both the hip and knee joints. We dissected the femoral and obturator nerves in human cadavers to investigate the distribution of the articular branches in the hip and knee joints. Fourteen embalmed left lower limbs from 14 Japanese adult cadavers (five from females, nine from males, average age 73.8 ± 14.1 years) were observed macroscopically. The articular branches of the femoral and obturator nerves were dissected at the anterior margin of the groin toward the thigh region. After dissections of the articular nerves of the hip joints, the femoral and obturator nerves were exposed from proximally to distally to identify the articular nerves of the knee joints. The branching pattern of the articular branches in the hip and knee joints was recorded. In six of 14 limbs (42.9%), the femoral nerve supplied articular branches to the anteromedial aspect of both the hip and knee joints. These articular branches were derived from the same bundle of femoral nerve. These gross anatomical findings suggested that dichotomizing peripheral sensory fibers innervate the hip and knee joints and these could relate to the referred pain confirmed in the anterior knee joints of patients with hip disease. Clin. Anat. 31:705-709, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Investigation Leads to Improved Understanding of Space Shuttle RSRM Internal Insulation Joints

NASA Technical Reports Server (NTRS)

McWhorter, Bruce B.; Bolton, Doug E.; Hicken, Steve V.; Allred, Larry D.; Cook, Dave J.

2003-01-01

PSA has been weakened due to humidity, then the J-joint will partially pull apart (inboard side), and the J-joint surfaces will be charred by exposure to hot gases. After early operation, a J-joint that has been pulled apart will come back together as the J-joint deformation decreases. This J-joint heating event is relatively short and occurs only during the first part of motor operation. Internal instrumentation was developed for another full-scale static test in February 2000. The static test instrumentation did indeed prove this theory to be correct. Post-test inspection revealed very similar charring characteristics as observed on RSRM-55. This experience of the development of a new PSA, its testing, the RSRM-55 flight, followed by the J-joint investigation led to good 'lessons learned' and to an additional fundamental understanding of the RSRM J-joint function.

Development of non-destructive examination techniques for CFC-metal joints in annular geometry and their application to the manufacturing of plasma-facing components

DOE Office of Scientific and Technical Information (OSTI.GOV)

Di Pietro, E.; Visca, E.; Orsini, A.

1995-12-31

The design of plasma-facing components for ITER, as for any of the envisaged next-step machines, relies heavily on the use of brazed junctions to couple armour materials to the heat sink and cooling tubes. Moreover, the typical number of brazed components and the envisaged effects of local overheating due to failure in a single brazed junction stress the importance of having a set of NDE techniques developed that can ensure the flawless quality of the joint. The qualification and application of two NDE techniques (ultrasonic and thermographic analysis) for inspection of CFC-to-metal joints is described with particular regard to themore » annular geometry typical of macroblock/monoblock solutions for divertor high-heat-flux components. The results of the eddy current inspection are not reported. The development has been focused specifically on the joint between carbon-fiber composite and TZM molybdenum alloy; techniques for the production of reference defect samples have been devised and a set of reference defect samples produced. The comparative results of the NDE inspections are reported and discussed, also on the basis of the destructive examination of the samples. The nature and size of relevant and detectable defects are discussed together with hints for a possible NDE strategy for divertor high-heat-flux components.« less

Distraction for proximal interphalangeal joint contractures: long-term results.

PubMed

Houshian, Shirzad; Jing, Shan Shan; Kazemian, Gholam Hussein; Emami-Moghaddam-Tehrani, Mohammad

2013-10-01

To report the medium- to long-term outcomes of joint distraction using a unilateral external fixator in the treatment of chronic post-traumatic proximal interphalangaeal (PIP) joint contractures. Between September 2001 and October 2011, 94 consecutive patients (98 PIP joints) with a mean age of 43 years (range, 17-69 y) were treated with external fixation for chronic flexion deformity of the PIP joint from trauma. The average time from injury to surgery was 48 months (range, 6-84 mo), and the duration of joint distraction was 10 days (range, 7-22 d). Patients were followed for a mean period of 54 months (range, 12-72 mo). The average gain in joint flexion was 25° and in joint extension was 40°. The mean improvement in the active range of movement was 67° (range. 30°-90°). There was no loss of motion on the latest follow-up. Patients younger than 40 years fared slightly better than those older than 40 years. Two patients developed swelling, pain, and erythema during treatment, which resolved upon temporarily stopping the distraction process. There were 12 cases of superficial pin-site infections, which were managed conservatively without serious complications or adverse outcome. External fixation is a simple and effective treatment modality for chronic traumatic PIP joint contractures with good predictable medium- to long-term results. Careful patient selection and monitoring are required. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Accuracy of acromioclavicular joint injections.

PubMed

Wasserman, Bradley R; Pettrone, Sarah; Jazrawi, Laith M; Zuckerman, Joseph D; Rokito, Andrew S

2013-01-01

Injection to the acromioclavicular (AC) joint can be both diagnostic and therapeutic. The purpose of this study was to evaluate the accuracy of in vivo AC joint injections. Case series; Level of evidence, 4. Thirty patients with pain localized to the AC joint were injected with 1 mL of 1% lidocaine and 0.5 mL of radiographic contrast material (Isovue). Radiographs of the AC joint were taken after the injection. Each radiograph was reviewed by a musculoskeletal radiologist and graded as intra-articular, extra-articular, or partially intra-articular. Of the 30 injections performed, 13 (43.3%) were intra-articular, 7 (23.3%) were partially articular, and 10 (33.3%) were extra-articular. When the intra-articular and the partially articular groups were combined, 20 patients (66.7%) had some contrast dye in the AC joint. This study demonstrates that despite the relatively superficial location of the AC joint, the clinical accuracy of AC joint injections remains relatively low.

Can symptomatic acromioclavicular joints be differentiated from asymptomatic acromioclavicular joints on 3-T MR imaging?

PubMed

Choo, Hye Jung; Lee, Sun Joo; Kim, Jung Han; Cha, Seong Sook; Park, Young Mi; Park, Ji Sung; Lee, Jun Woo; Oh, Minkyung

2013-04-01

To evaluate retrospectively whether symptomatic acromioclavicular joints can be differentiated from asymptomatic acromioclavicular joints on 3-T MR imaging. This study included 146 patients who underwent physical examination of acromioclavicular joints and 3-T MR imaging of the shoulder. Among them, 67 patients showing positive results on physical examination were assigned to the symptomatic group, whereas 79 showing negative results were assigned to the asymptomatic group. The following MR findings were compared between the symptomatic and asymptomatic groups: presence of osteophytes, articular surface irregularity, subchondral cysts, acromioclavicular joint fluid, subacromial fluid, subacromial bony spurs, joint capsular distension, bone edema, intraarticular enhancement, periarticular enhancement, superior and inferior joint capsular distension degree, and joint capsular thickness. The patients were subsequently divided into groups based on age (younger, older) and the method of MR arthrography (direct MR arthrography, indirect MR arthrography), and all the MR findings in each subgroup were reanalyzed. The meaningful cutoff value of each significant continuous variable was calculated using receiver operating characteristic analysis. The degree of superior capsular distension was the only significant MR finding of symptomatic acromioclavicular joints and its meaningful cutoff value was 2.1mm. After subgroup analyses, this variable was significant in the older age group and indirect MR arthrography group. On 3-T MR imaging, the degree of superior joint capsular distension might be a predictable MR finding in the diagnosis of symptomatic acromioclavicular joints. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Generalized Cross Entropy Method for estimating joint distribution from incomplete information

NASA Astrophysics Data System (ADS)

Xu, Hai-Yan; Kuo, Shyh-Hao; Li, Guoqi; Legara, Erika Fille T.; Zhao, Daxuan; Monterola, Christopher P.

2016-07-01

Obtaining a full joint distribution from individual marginal distributions with incomplete information is a non-trivial task that continues to challenge researchers from various domains including economics, demography, and statistics. In this work, we develop a new methodology referred to as ;Generalized Cross Entropy Method; (GCEM) that is aimed at addressing the issue. The objective function is proposed to be a weighted sum of divergences between joint distributions and various references. We show that the solution of the GCEM is unique and global optimal. Furthermore, we illustrate the applicability and validity of the method by utilizing it to recover the joint distribution of a household profile of a given administrative region. In particular, we estimate the joint distribution of the household size, household dwelling type, and household home ownership in Singapore. Results show a high-accuracy estimation of the full joint distribution of the household profile under study. Finally, the impact of constraints and weight on the estimation of joint distribution is explored.

Functional disorders of the temporomandibular joints: Internal derangement of the temporomandibular joint.

PubMed

Chang, Chih-Ling; Wang, Ding-Han; Yang, Mu-Chen; Hsu, Wun-Eng; Hsu, Ming-Lun

2018-04-01

Temporomandibular joint (TMJ) is one of the most complex joints of the human body. Due to its unique movement, in terms of combination of rotation and translator movement, disc of the joint plays an important role to maintain its normal function. In order to sustain the normal function of the TMJ, disc must be kept in proper position as well as maintain normal shape in all circumstances. Once the disc is not any more in its normal position during function of the joint, disturbance of the joint can be occurred which will lead to subsequent distortion of the disc. Shape of the disc can be influenced by many factors i.e.: abnormal function or composition of the disc itself. Etiology of the internal derangement of the disc remains controversial. Multifactorial theory has been postulated in most of previous manuscripts. Disc is composed of mainly extracellular matrix. Abnormal proportion of collagen type I & III may also leads to joint hypermobility which may be also a predisposing factor of this disorder. Thus it can be recognized as local manifestation of a systemic disorder. Different treatment modalities with from conservative treatment to surgical intervention distinct success rate have been reported. Recently treatment with extracellular matrix injection becomes more and more popular to strengthen the joint itself. Since multifactorial in character, the best solution of the treatment modalities should be aimed to resolve possible etiology from different aspects. Team work may be indication to reach satisfied results. Copyright © 2018. Published by Elsevier Taiwan.

Predicting the Functional Roles of Knee Joint Muscles from Internal Joint Moments.

PubMed

Flaxman, Teresa E; Alkjær, Tine; Simonsen, Erik B; Krogsgaard, Michael R; Benoit, Daniel L

2017-03-01

Knee muscles are commonly labeled as flexors or extensors and aptly stabilize the knee against sagittal plane loads. However, how these muscles stabilize the knee against adduction-abduction and rotational loads remains unclear. Our study sought 1) to classify muscle roles as they relate to joint stability by quantifying the relationship between individual muscle activation patterns and internal net joint moments in all three loading planes and 2) to determine whether these roles change with increasing force levels. A standing isometric force matching protocol required subjects to modulate ground reaction forces to elicit various combinations and magnitudes of sagittal, frontal, and transverse internal joint moments. Surface EMG measured activities of 10 lower limb muscles. Partial least squares regressions determined which internal moment(s) were significantly related to the activation of individual muscles. Rectus femoris and tensor fasciae latae were classified as moment actuators for knee extension and hip flexion. Hamstrings were classified as moment actuators for hip extension and knee flexion. Gastrocnemius and hamstring muscles were classified as specific joint stabilizers for knee rotation. Vastii were classified as general joint stabilizers because activation was independent of moment generation. Muscle roles did not change with increasing effort levels. Our findings indicate muscle activation is not dependent on anatomical orientation but perhaps on its role in maintaining knee joint stability in the frontal and transverse loading planes. This is useful for delineating the roles of biarticular knee joint muscles and could have implications in robotics, musculoskeletal modeling, sports sciences, and rehabilitation.

Fully automated system for the quantification of human osteoarthritic knee joint effusion volume using magnetic resonance imaging.

PubMed

Li, Wei; Abram, François; Pelletier, Jean-Pierre; Raynauld, Jean-Pierre; Dorais, Marc; d'Anjou, Marc-André; Martel-Pelletier, Johanne

2010-01-01

Joint effusion is frequently associated with osteoarthritis (OA) flare-up and is an important marker of therapeutic response. This study aimed at developing and validating a fully automated system based on magnetic resonance imaging (MRI) for the quantification of joint effusion volume in knee OA patients. MRI examinations consisted of two axial sequences: a T2-weighted true fast imaging with steady-state precession and a T1-weighted gradient echo. An automated joint effusion volume quantification system using MRI was developed and validated (a) with calibrated phantoms (cylinder and sphere) and effusion from knee OA patients; (b) with assessment by manual quantification; and (c) by direct aspiration. Twenty-five knee OA patients with joint effusion were included in the study. The automated joint effusion volume quantification was developed as a four stage sequencing process: bone segmentation, filtering of unrelated structures, segmentation of joint effusion, and subvoxel volume calculation. Validation experiments revealed excellent coefficients of variation with the calibrated cylinder (1.4%) and sphere (0.8%) phantoms. Comparison of the OA knee joint effusion volume assessed by the developed automated system and by manual quantification was also excellent (r = 0.98; P < 0.0001), as was the comparison with direct aspiration (r = 0.88; P = 0.0008). The newly developed fully automated MRI-based system provided precise quantification of OA knee joint effusion volume with excellent correlation with data from phantoms, a manual system, and joint aspiration. Such an automated system will be instrumental in improving the reproducibility/reliability of the evaluation of this marker in clinical application.

New Joint Sealants. Criteria, Design and Materials.

ERIC Educational Resources Information Center

Building Research Inst., Inc., Washington, DC.

Contents include--(1) sealing concrete joints, (2) sealing glass and metal joints, (3) metal and glass joint sealants from a fabricator's viewpoint, (4) a theory of adhesion for joint sealants, (5) geometry of simple joint seals under strain, (6) joint sealant specifications from a manufacturer's viewpoint, (7) joint sealant requirements from an…

Joint surface modeling with thin-plate splines.

PubMed

Boyd, S K; Ronsky, J L; Lichti, D D; Salkauskas, K; Chapman, M A; Salkauskas, D

1999-10-01

Mathematical joint surface models based on experimentally determined data points can be used to investigate joint characteristics such as curvature, congruency, cartilage thickness, joint contact areas, as well as to provide geometric information well suited for finite element analysis. Commonly, surface modeling methods are based on B-splines, which involve tensor products. These methods have had success; however, they are limited due to the complex organizational aspect of working with surface patches, and modeling unordered, scattered experimental data points. An alternative method for mathematical joint surface modeling is presented based on the thin-plate spline (TPS). It has the advantage that it does not involve surface patches, and can model scattered data points without experimental data preparation. An analytical surface was developed and modeled with the TPS to quantify its interpolating and smoothing characteristics. Some limitations of the TPS include discontinuity of curvature at exactly the experimental surface data points, and numerical problems dealing with data sets in excess of 2000 points. However, suggestions for overcoming these limitations are presented. Testing the TPS with real experimental data, the patellofemoral joint of a cat was measured with multistation digital photogrammetry and modeled using the TPS to determine cartilage thicknesses and surface curvature. The cartilage thickness distribution ranged between 100 to 550 microns on the patella, and 100 to 300 microns on the femur. It was found that the TPS was an effective tool for modeling joint surfaces because no preparation of the experimental data points was necessary, and the resulting unique function representing the entire surface does not involve surface patches. A detailed algorithm is presented for implementation of the TPS.

Biochemical and biomechanical characterisation of equine cervical facet joint cartilage.

PubMed

O'Leary, S A; White, J L; Hu, J C; Athanasiou, K A

2018-04-15

is the first study to report the properties of equine cervical facet joint cartilage and may serve as the foundation for the development of future tissue-engineered replacements as well as other treatment strategies. © 2018 EVJ Ltd.

Temporomandibular Joint Imaging.

PubMed

Tamimi, Dania; Jalali, Elnaz; Hatcher, David

2018-01-01

The temporomandibular joint (TMJ) is an anatomically and biomechanically complex structure. Understanding how this structure grows and functions is essential to accurate radiographic evaluation. This article discusses the anatomy, function, and growth and development of the TMJ and how growth changes can affect the morphology of the craniofacial structures. Accordingly, the radiographic appearance of the entities that may alter the TMJ are discussed, including developmental, degenerative, inflammatory, and traumatic changes. Both osseous imaging and soft tissue imaging are shown. Copyright © 2017 Elsevier Inc. All rights reserved.

Identification of inflammation sites in arthritic joints using hyperspectral imaging

NASA Astrophysics Data System (ADS)

Paluchowski, Lukasz A.; Milanic, Matija; Bjorgan, Asgeir; Grandaunet, Berit; Dhainaut, Alvilde; Hoff, Mari; Randeberg, Lise L.

2014-03-01

Inflammatory arthritic diseases have prevalence between 2 and 3% and may lead to joint destruction and deformation resulting in a loss of function. Patient's quality of life is often severely affected as the disease attacks hands and finger joints. Pathology involved in arthritis includes angiogenesis, hyper-vascularization, hyper-metabolism and relative hypoxia. We have employed hyperspectral imaging to study the hemodynamics of affected- and non-affected joints and tissue. Two hyperspectral, push-broom cameras were used (VNIR-1600, SWIR-320i, Norsk Elektro Optikk AS, Norway). Optical spectra (400nm - 1700nm) of high spectral resolution were collected from 15 patients with visible symptoms of arthritic rheumatic diseases in at least one joint. The control group consisted of 10 healthy individuals. Concentrations of dominant chromophores were calculated based on analytical calculations of light transport in tissue. Image processing was used to analyze hyperspectral data and retrieve information, e.g. blood concentration and tissue oxygenation maps. The obtained results indicate that hyperspectral imaging can be used to quantify changes within affected joints and surrounding tissue. Further improvement of this method will have positive impact on diagnosis of arthritic joints at an early stage. Moreover it will enable development of fast, noninvasive and noncontact diagnostic tool of arthritic joints

Steroid injections - tendon, bursa, joint

MedlinePlus

... a small amount of corticosteroid and a local anesthetic into the bursa. JOINT Any joint problem, such ... A small amount of corticosteroid and a local anesthetic will be injected into the joint. TENDON A ...

High pressure ceramic joint

DOEpatents

Ward, M.E.; Harkins, B.D.

1993-11-30

Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present joint when used with recuperators increases the use of ceramic components which do not react to highly corrosive gases. Thus, the present joint used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present joint is comprised of a first ceramic member, a second ceramic member, a mechanical locking device having a groove defined in one of the first ceramic member and the second ceramic member. The joint and the mechanical locking device is further comprised of a refractory material disposed in the groove and contacting the first ceramic member and the second ceramic member. The present joint mechanically provides a high strength load bearing joint having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures. 4 figures.

Metal to ceramic sealed joint

DOEpatents

Lasecki, J.V.; Novak, R.F.; McBride, J.R.

1991-08-27

A metal to ceramic sealed joint which can withstand wide variations in temperature and maintain a good seal is provided for use in a device adapted to withstand thermal cycling from about 20 to about 1000 degrees C. The sealed joint includes a metal member, a ceramic member having an end portion, and an active metal braze forming a joint to seal the metal member to the ceramic member. The joint is positioned remote from the end portion of the ceramic member to avoid stresses at the ends or edges of the ceramic member. The sealed joint is particularly suited for use to form sealed metal to ceramic joints in a thermoelectric generator such as a sodium heat engine where a solid ceramic electrolyte is joined to metal parts in the system. 11 figures.

Metal to ceramic sealed joint

DOEpatents

Lasecki, John V.; Novak, Robert F.; McBride, James R.

1991-01-01

A metal to ceramic sealed joint which can withstand wide variations in temperature and maintain a good seal is provided for use in a device adapted to withstand thermal cycling from about 20 to about 1000 degrees C. The sealed joint includes a metal member, a ceramic member having an end portion, and an active metal braze forming a joint to seal the metal member to the ceramic member. The joint is positioned remote from the end portion of the ceramic member to avoid stresses at the ends or edges of the ceramic member. The sealed joint is particularly suited for use to form sealed metal to ceramic joints in a thermoelectric generator such as a sodium heat engine where a solid ceramic electrolyte is joined to metal parts in the system.

Unweaving the joints in Entrada Sandstone, Arches National Park, Utah, U.S.A.

NASA Astrophysics Data System (ADS)

Cruikshank, Kenneth M.; Aydin, Atilla

1995-03-01

On the southwest limb of Salt Valley Anticline, Arches National Park, Utah three sets of joints are developed in the Entrada Sandstone covering an area of about 6 km 2. Within the 20 m thick Moab Member, a single joint set is is found in three distinct areas, separated by a second set of joints at a 35° angle to the first set. Joint interaction features show that the second set is younger than the first. This illustrates that joints of a single set do not have to fill the entire area across which the stresses that formed the joints were acting. The underlying Slickrock Member contains a third set of joints, which is at an angle of 5°-35° to joints in the Moab Member. The Slickrock set nucleated from the lower edges of joints of all orientations in the overlying Moab Member. Thus, the fracture pattern evolved both horizontally, within the same unit, and vertically between units. The sequence of jointing is determined by establishing the relative ages of each joint set. Each joint orientation is best interpreted as representing a direction of maximum compression, ruling out the possibility that the joints are a conjugate set. The joints, and an earlier set of deformation bands, record a 95° counterclockwise rotation of the direction of maximum compression.

Dataglove measurement of joint angles in sign language handshapes

PubMed Central

Eccarius, Petra; Bour, Rebecca; Scheidt, Robert A.

2012-01-01

In sign language research, we understand little about articulatory factors involved in shaping phonemic boundaries or the amount (and articulatory nature) of acceptable phonetic variation between handshapes. To date, there exists no comprehensive analysis of handshape based on the quantitative measurement of joint angles during sign production. The purpose of our work is to develop a methodology for collecting and visualizing quantitative handshape data in an attempt to better understand how handshapes are produced at a phonetic level. In this pursuit, we seek to quantify the flexion and abduction angles of the finger joints using a commercial data glove (CyberGlove; Immersion Inc.). We present calibration procedures used to convert raw glove signals into joint angles. We then implement those procedures and evaluate their ability to accurately predict joint angle. Finally, we provide examples of how our recording techniques might inform current research questions. PMID:23997644

Sacroiliac joint tuberculosis

PubMed Central

Govender, S.

2006-01-01

Infections of the sacroiliac joint are uncommon and the diagnosis is usually delayed. In a retrospective study, 17 patients who had been treated for tuberculosis sacroiliitis between 1994 and 2004 were reviewed. Two patients were excluded due to a short follow-up (less than 2 years). Low back pain and difficulty in walking were the most common presenting features. Two patients presented with a buttock abscess and spondylitis of the lumbar spine was noted in two patients. The Gaenslen’s and FABER (flexion, abduction and external rotation) tests were positive in all patients. Radiological changes included loss of cortical margins with erosion of the joints. An open biopsy and curettage was performed in all patients; histology revealed chronic infection and acid-fast bacilli were isolated in nine patients. Antituberculous (TB) medication was administered for 18 months and the follow-up ranged from 3 to 10 years (mean: 5 years). The sacroiliac joint fused spontaneously within 2 years. Although all patients had mild discomfort in the lower back following treatment they had no difficulty in walking. Sacroiliac joint infection must be included in the differential diagnosis of lower back pain and meticulous history and clinical evaluation of the joint are essential. PMID:16673102

Lower limb joint work and joint work contribution during downhill and uphill walking at different inclinations.

PubMed

Alexander, Nathalie; Strutzenberger, Gerda; Ameshofer, Lisa Maria; Schwameder, Hermann

2017-08-16

Work performance and individual joint contribution to total work are important information for creating training protocols, but were not assessed so far for sloped walking. Therefore, the purpose of this study was to analyze lower limb joint work and joint contribution of the hip, knee and ankle to total lower limb work during sloped walking in a healthy population. Eighteen male participants (27.0±4.7yrs, 1.80±0.05m, 74.5±8.2kg) walked on an instrumented ramp at inclination angles of 0°, ±6°, ±12° and ±18° at 1.1m/s. Kinematic and kinetic data were captured using a motion-capture system (Vicon) and two force plates (AMTI). Joint power curves, joint work (positive, negative, absolute) and each joint's contribution to total lower limb work were analyzed throughout the stance phase using an ANOVA with repeated measures. With increasing inclination positive joint work increased for the ankle and hip joint and in total during uphill walking. Negative joint work increased for each joint and in total work during downhill walking. Absolute work was increased during both uphill (all joints) and downhill (ankle & knee) walking. Knee joint contribution to total negative and absolute work increased during downhill walking while hip and ankle contributions decreased. This study identified, that, when switching from level to a 6° and from 6° to a 12° inclination the gain of individual joint work is more pronounced compared to switching from 12° to an 18° inclination. The results might be used for training recommendations and specific training intervention with respect to sloped walking. Copyright © 2017 Elsevier Ltd. All rights reserved.

Osteoarthritis of the distal interphalangeal joint.

PubMed

Kaufmann, Robert A; Lögters, Tim T; Verbruggen, Gust; Windolf, Joachim; Goitz, Robert J

2010-12-01

Osteoarthritis occurs with the highest prevalence in the distal interphalangeal joint of the hand and has been divided into an erosive and a nonerosive form. The pathogenesis of the early stages of osteoarthritis is poorly understood, but considerable emphasis has been placed on the role of cartilage and subchondral bone as well as soft tissue structures such as collateral ligaments and tendons. Radiographic evaluation represents the most standardized method to quantify disease progression, with different systems having been developed for defining and grading radiographic features. This current concepts article examines the recent knowledge base regarding the etiology, pathogenesis, and evaluation of osteoarthritis of the distal interphalangeal joint. Copyright © 2010. Published by Elsevier Inc.

Robotic Joints Support Horses and Humans

NASA Technical Reports Server (NTRS)

2008-01-01

A rehabilitative device first featured in Spinoff 2003 is not only helping human patients regain the ability to walk, but is now helping our four-legged friends as well. The late James Kerley, a prominent Goddard Space Flight Center researcher, developed cable-compliant mechanisms in the 1980s to enable sounding rocket assemblies and robots to grip or join objects. In cable-compliant joints (CCJs), short segments of cable connect structural elements, allowing for six directions of movement, twisting, alignment, and energy damping. Kerley later worked with Goddard s Wayne Eklund and Allen Crane to incorporate the cable-compliant mechanisms into a walker for human patients to support the pelvis and imitate hip joint movement.

Fabrication and Assembly of High-Precision Hinge and Latch Joints for Deployable Optical Instruments

NASA Technical Reports Server (NTRS)

Phelps, James E.

1999-01-01

Descriptions are presented of high-precision hinge and latch joints that have been co-developed, for application to deployable optical instruments, by NASA Langley Research Center and Nyma/ADF. Page-sized versions of engineering drawings are included in two appendices to describe all mechanical components of both joints. Procedures for assembling the mechanical components of both joints are also presented. The information herein is intended to facilitate the fabrication and assembly of the high-precision hinge and latch joints, and enable the incorporation of these joints into the design of deployable optical instrument systems.

[Temporo-mandibular joint. Morpho-functional considerations].

PubMed

Scutariu, M D; Indrei, Anca

2004-01-01

The temporo-mandibular joint is distinguished from most other synovial joints of the body by two features: 1. the two jointed components carry teeth whose position and occlusion introduce a very strong influence on the movements of the temporo-mandibular joint and 2. its articular surfaces are not covered by hyaline cartilage, but by a dense, fibrous tissue. This paper describes the parts of the temporo-mandibular joint: the articular surfaces (the condylar process of the mandible and the glenoid part of the temporal bone), the fibrocartilaginous disc which is interposed between the mandibular and the temporal surface, the fibrous capsule of the temporo-mandibular joint and the ligaments of this joint. All these parts present a very strong adaptation at the important functions of the temporo-mandibular joint.

Utilization of Facet Joint and Sacroiliac Joint Interventions in Medicare Population from 2000 to 2014: Explosive Growth Continues!

PubMed

Manchikanti, Laxmaiah; Hirsch, Joshua A; Pampati, Vidyasagar; Boswell, Mark V

2016-10-01

Increasing utilization of interventional techniques in managing chronic spinal pain, specifically facet joint interventions and sacroiliac joint injections, is a major concern of healthcare policy makers. We analyzed the patterns of utilization of facet and sacroiliac joint interventions in managing chronic spinal pain. The results showed significant increase of facet joint interventions and sacroiliac joint injections from 2000 to 2014 in Medicare FFS service beneficiaries. Overall, the Medicare population increased 35 %, whereas facet joint and sacroiliac joint interventions increased 313.3 % per 100,000 Medicare population with an annual increase of 10.7 %. While the increases were uniform from 2000 to 2014, there were some decreases noted for facet joint interventions in 2007, 2010, and 2013, whereas for sacroiliac joint injections, the decreases were noted in 2007 and 2013. The increases were for cervical and thoracic facet neurolysis at 911.5 % compared to lumbosacral facet neurolysis of 567.8 %, 362.9 % of cervical and thoracic facet joint blocks, 316.9 % of sacroiliac joints injections, and finally 227.3 % of lumbosacral facet joint blocks.

Development of Flow and Heat Transfer Models for the Carbon Fiber Rope in Nozzle Joints of the Space Shuttle Reusable Solid Rocket Motor

NASA Technical Reports Server (NTRS)

Wang, Q.; Ewing, M. E.; Mathias, E. C.; Heman, J.; Smith, C.; McCool, Alex (Technical Monitor)

2001-01-01

Methodologies have been developed for modeling both gas dynamics and heat transfer inside the carbon fiber rope (CFR) for applications in the space shuttle reusable solid rocket motor joints. Specifically, the CFR is modeled using an equivalent rectangular duct with a cross-section area, friction factor and heat transfer coefficient such that this duct has the same amount of mass flow rate, pressure drop, and heat transfer rate as the CFR. An equation for the friction factor is derived based on the Darcy-Forschheimer law and the heat transfer coefficient is obtained from pipe flow correlations. The pressure, temperature and velocity of the gas inside the CFR are calculated using the one-dimensional Navier-Stokes equations. Various subscale tests, both cold flow and hot flow, have been carried out to validate and refine this CFR model. In particular, the following three types of testing were used: (1) cold flow in a RSRM nozzle-to-case joint geometry, (2) cold flow in a RSRM nozzle joint No. 2 geometry, and (3) hot flow in a RSRM nozzle joint environment simulator. The predicted pressure and temperature history are compared with experimental measurements. The effects of various input parameters for the model are discussed in detail.

Ball-joint grounding ring

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.

Developing a test method to investigate water susceptibility of joint and crack sealants.

DOT National Transportation Integrated Search

2016-10-31

Sealants are commonly used to insulate cracks and joints preventing water from entering the underlying structure. However, extended exposure of sealants to water has shown to negatively impact sealants properties causing gradual degradation of sealan...

Development of a Geospatial Data-Sharing Method for Unmanned Vehicles Based on the Joint Architecture for Unmanned Systems (JAUS)

DTIC Science & Technology

2005-08-01

the Office of the Secretary of Defense chartered the Joint Architecture for Unmanned Ground Systems ( JAUGS ) Working Group to address these concerns...The JAUGS Working Group was tasked with developing an initial standard for interoperable unmanned ground systems. In 2002, the charter of the... JAUGS Working Group was 1 2 modified such that their efforts would extend to all unmanned systems, not only ground systems. The standard was

An algorithm for continuum modeling of rocks with multiple embedded nonlinearly-compliant joints [Continuum modeling of elasto-plastic media with multiple embedded nonlinearly-compliant joints

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hurley, R. C.; Vorobiev, O. Y.; Ezzedine, S. M.

Here, we present a numerical method for modeling the mechanical effects of nonlinearly-compliant joints in elasto-plastic media. The method uses a series of strain-rate and stress update algorithms to determine joint closure, slip, and solid stress within computational cells containing multiple “embedded” joints. This work facilitates efficient modeling of nonlinear wave propagation in large spatial domains containing a large number of joints that affect bulk mechanical properties. We implement the method within the massively parallel Lagrangian code GEODYN-L and provide verification and examples. We highlight the ability of our algorithms to capture joint interactions and multiple weakness planes within individualmore » computational cells, as well as its computational efficiency. We also discuss the motivation for developing the proposed technique: to simulate large-scale wave propagation during the Source Physics Experiments (SPE), a series of underground explosions conducted at the Nevada National Security Site (NNSS).« less

An algorithm for continuum modeling of rocks with multiple embedded nonlinearly-compliant joints [Continuum modeling of elasto-plastic media with multiple embedded nonlinearly-compliant joints

DOE PAGES

Hurley, R. C.; Vorobiev, O. Y.; Ezzedine, S. M.

2017-04-06

Here, we present a numerical method for modeling the mechanical effects of nonlinearly-compliant joints in elasto-plastic media. The method uses a series of strain-rate and stress update algorithms to determine joint closure, slip, and solid stress within computational cells containing multiple “embedded” joints. This work facilitates efficient modeling of nonlinear wave propagation in large spatial domains containing a large number of joints that affect bulk mechanical properties. We implement the method within the massively parallel Lagrangian code GEODYN-L and provide verification and examples. We highlight the ability of our algorithms to capture joint interactions and multiple weakness planes within individualmore » computational cells, as well as its computational efficiency. We also discuss the motivation for developing the proposed technique: to simulate large-scale wave propagation during the Source Physics Experiments (SPE), a series of underground explosions conducted at the Nevada National Security Site (NNSS).« less

A new kind of end-glued joint for the hardwood industry

Treesearch

Philip A. Araman

1973-01-01

A method has been developed for end- and edge-gluing short pieces of high-value hardwood lumber into long panels, using a curved end joint we call SEM (Serpentine End Matching). Panels containing SEM end joints are aesthetically pleasing and are suited for exposed applications such as in finished furniture.

22 CFR 228.34 - Joint ventures.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Joint ventures. 228.34 Section 228.34 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT RULES ON SOURCE, ORIGIN AND NATIONALITY FOR COMMODITIES AND SERVICES FINANCED BY USAID Conditions Governing the Nationality of Suppliers of Services for USAID...

14 CFR 23.693 - Joints.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Systems § 23.693 Joints. Control system joints (in push-pull systems) that are subject to angular motion... factor may be reduced to 2.0 for joints in cable control systems. For ball or roller bearings, the...

Wrist joint assembly

NASA Technical Reports Server (NTRS)

Kersten, L.; Johnson, J. D. (Inventor)

1978-01-01

A wrist joint assembly is provided for use with a mechanical manipulator arm for finely positioning an end-effector carried by the wrist joint on the terminal end of the manipulator arm. The wrist joint assembly is pivotable about a first axis to produce a yaw motion, a second axis is to produce a pitch motion, and a third axis to produce a roll motion. The wrist joint assembly includes a disk segment affixed to the terminal end of the manipulator arm and a first housing member, a second housing member, and a third housing member. The third housing member and the mechanical end-effector are moved in the yaw, pitch, and roll motion. Drive means are provided for rotating each of the housings about their respective axis which includes a cluster of miniature motors having spur gears carried on the output drive shaft which mesh with a center drive gear affixed on the housing to be rotated.

Simulation and Experiment Research on Fatigue Life of High Pressure Air Pipeline Joint

NASA Astrophysics Data System (ADS)

Shang, Jin; Xie, Jianghui; Yu, Jian; Zhang, Deman

2017-12-01

High pressure air pipeline joint is important part of high pressure air system, whose reliability is related to the safety and stability of the system. This thesis developed a new type-high pressure air pipeline joint, carried out dynamics research on CB316-1995 and new type-high pressure air pipeline joint with finite element method, deeply analysed the join forms of different design schemes and effect of materials on stress, tightening torque and fatigue life of joint. Research team set up vibration/pulse test bench, carried out joint fatigue life contrast test. The result shows: the maximum stress of the joint is inverted in the inner side of the outer sleeve nut, which is consistent with the failure mode of the crack on the outer sleeve nut in practice. Simulation and experiment of fatigue life and tightening torque of new type-high pressure air pipeline joint are better than CB316-1995 joint.

Modeling joint restoration strategies for interdependent infrastructure systems

PubMed Central

Simonovic, Slobodan P.

2018-01-01

Life in the modern world depends on multiple critical services provided by infrastructure systems which are interdependent at multiple levels. To effectively respond to infrastructure failures, this paper proposes a model for developing optimal joint restoration strategy for interdependent infrastructure systems following a disruptive event. First, models for (i) describing structure of interdependent infrastructure system and (ii) their interaction process, are presented. Both models are considering the failure types, infrastructure operating rules and interdependencies among systems. Second, an optimization model for determining an optimal joint restoration strategy at infrastructure component level by minimizing the economic loss from the infrastructure failures, is proposed. The utility of the model is illustrated using a case study of electric-water systems. Results show that a small number of failed infrastructure components can trigger high level failures in interdependent systems; the optimal joint restoration strategy varies with failure occurrence time. The proposed models can help decision makers to understand the mechanisms of infrastructure interactions and search for optimal joint restoration strategy, which can significantly enhance safety of infrastructure systems. PMID:29649300

Modeling joint restoration strategies for interdependent infrastructure systems.

PubMed

Zhang, Chao; Kong, Jingjing; Simonovic, Slobodan P

2018-01-01

Life in the modern world depends on multiple critical services provided by infrastructure systems which are interdependent at multiple levels. To effectively respond to infrastructure failures, this paper proposes a model for developing optimal joint restoration strategy for interdependent infrastructure systems following a disruptive event. First, models for (i) describing structure of interdependent infrastructure system and (ii) their interaction process, are presented. Both models are considering the failure types, infrastructure operating rules and interdependencies among systems. Second, an optimization model for determining an optimal joint restoration strategy at infrastructure component level by minimizing the economic loss from the infrastructure failures, is proposed. The utility of the model is illustrated using a case study of electric-water systems. Results show that a small number of failed infrastructure components can trigger high level failures in interdependent systems; the optimal joint restoration strategy varies with failure occurrence time. The proposed models can help decision makers to understand the mechanisms of infrastructure interactions and search for optimal joint restoration strategy, which can significantly enhance safety of infrastructure systems.

Joint Force Quarterly. Issue 48, 1st Quarter 2008

DTIC Science & Technology

2008-01-01

Closure and joint basing initiatives. n Engage in the development of a broad- based, flexible, effective , and affordable joint military health care system...in a London hospital in November 2006 due to ingested alpha particles from Polonium 210 . Just the trace trail of Polonium 210 across the city and...can we adequately defend the Nation. Therefore, we will: n Determine the true health of our ground forces in terms of people, training, equipment

Development and morphogenesis of human wrist joint during embryonic and early fetal period

PubMed Central

Hita-Contreras, Fidel; Martínez-Amat, Antonio; Ortiz, Raúl; Caba, Octavio; Álvarez, Pablo; Prados, José C; Lomas-Vega, Rafael; Aránega, Antonia; Sánchez-Montesinos, Indalecio; Mérida-Velasco, Juan A

2012-01-01

The development of the human wrist joint has been studied widely, with the main focus on carpal chondrogenesis, ligaments and triangular fibrocartilage. However, there are some discrepancies concerning the origin and morphogenetic time-table of these structures, including nerves, muscles and vascular elements. For this study we used serial sections of 57 human embryonic (n = 30) and fetal (n = 27) specimens from O’Rahilly stages 17–23 and 9–14 weeks, respectively. The following phases in carpal morphogenesis have been established: undifferentiated mesenchyme (stage 17), condensated mesenchyme (stages 18 and 19), pre-chondrogenic (stages 19 and 20) and chondrogenic (stages 21 and over). Carpal chondrification and osteogenic processes are similar, starting with capitate and hamate (stage 19) and ending with pisiform (stage 22). In week 14, a vascular bud penetrates into the lunate cartilaginous mold, early sign of the osteogenic process that will be completed after birth. In stage 18, median, ulnar and radial nerves and thenar eminence appear in the hand plate. In stage 21, there are indications of the interosseous muscles, and in stage 22 flexor digitorum superficialis, flexor digitorum profundus and lumbrical muscles, transverse carpal ligament and collateral ligaments emerge. In stage 23, the articular disc, radiocarpal and ulnocarpal ligaments and deep palmar arterial arch become visible. Radiate carpal and interosseous ligaments appear in week 9, and in week 10, dorsal radiocarpal ligament and articular capsule are evident. Finally, synovial membrane is observed in week 13. We have performed a complete analysis of the morphogenesis of the structures of the human wrist joint. Our results present new data on nervous and arterial elements and provide the basis for further investigations on anatomical pathology, comparative morphology and evolutionary anthropology. PMID:22428933

Sacroiliac joint pain in the pediatric population.

PubMed

Stoev, Ivan; Powers, Alexander K; Puglisi, Joan A; Munro, Rebecca; Leonard, Jeffrey R

2012-06-01

The sacroiliac (SI) joint can be a pain generator in 13%-27% of cases of back pain in adults. These numbers are largely unknown for the pediatric population. In children and especially girls, development of the pelvic girdle makes the SI joint prone to misalignment. Young athletes sustain repeated stress on their SI joints, and sometimes even minor trauma can result in lasting pain that mimics radiculopathy. The authors present a series of 48 pediatric patients who were evaluated for low-back pain and were found to have SI joint misalignment as the cause of their symptoms. They were treated with a simple maneuver described in this paper that realigned their SI joint and provided significant improvement of symptoms. A retrospective review of the electronic records identified 48 patients who were referred with primary complaints of low-back pain and were determined to have SI joint misalignment during bedside examination maneuvers described here. Three patients did not have a record of their response to treatment and were excluded. Patients were evaluated by a physical therapist and had the realignment procedure performed on the day of initial consultation. The authors collected data regarding the immediate effect of the procedure, as well as the duration of pain relief at follow-up visits. Eighty percent of patients experienced dramatic improvement in symptoms that had a lasting effect after the initial treatment. The majority of them were given a home exercise program, and only 2 of the 36 patients who experienced significant relief had to be treated again. Fifty-three percent of all patients had immediate and complete resolution of symptoms. Three of the 48 patients had missing data from the medical records and were excluded from computations. Back pain is multifactorial, and the authors' data demonstrate the potential importance of SI joint pathology. Although the technique described here for treatment of misaligned SI joints in the pediatric patients is not

Product evaluation : Ruscoe 983 joint sealant

DOT National Transportation Integrated Search

1986-07-10

This report contains a product evaluation of Ruscoe's 983 joint sealant. Ruscoe 983 is an asphalt base single compound joint sealant. It contains an aluminum fortified adhesive and is designed for use on highway expansion joints, bridge joints, and r...

Fully automated system for the quantification of human osteoarthritic knee joint effusion volume using magnetic resonance imaging

PubMed Central

2010-01-01

Introduction Joint effusion is frequently associated with osteoarthritis (OA) flare-up and is an important marker of therapeutic response. This study aimed at developing and validating a fully automated system based on magnetic resonance imaging (MRI) for the quantification of joint effusion volume in knee OA patients. Methods MRI examinations consisted of two axial sequences: a T2-weighted true fast imaging with steady-state precession and a T1-weighted gradient echo. An automated joint effusion volume quantification system using MRI was developed and validated (a) with calibrated phantoms (cylinder and sphere) and effusion from knee OA patients; (b) with assessment by manual quantification; and (c) by direct aspiration. Twenty-five knee OA patients with joint effusion were included in the study. Results The automated joint effusion volume quantification was developed as a four stage sequencing process: bone segmentation, filtering of unrelated structures, segmentation of joint effusion, and subvoxel volume calculation. Validation experiments revealed excellent coefficients of variation with the calibrated cylinder (1.4%) and sphere (0.8%) phantoms. Comparison of the OA knee joint effusion volume assessed by the developed automated system and by manual quantification was also excellent (r = 0.98; P < 0.0001), as was the comparison with direct aspiration (r = 0.88; P = 0.0008). Conclusions The newly developed fully automated MRI-based system provided precise quantification of OA knee joint effusion volume with excellent correlation with data from phantoms, a manual system, and joint aspiration. Such an automated system will be instrumental in improving the reproducibility/reliability of the evaluation of this marker in clinical application. PMID:20846392

Gene-expression changes in knee-joint tissues with aging and menopause: implications for the joint as an organ

PubMed Central

Rollick, Natalie C; Lemmex, Devin B; Ono, Yohei; Reno, Carol R; Hart, David A; Lo, Ian KY; Thornton, Gail M

2018-01-01

Background When considering the “joint as an organ”, the tissues in a joint act as complementary components of an organ, and the “set point” is the cellular activity for homeostasis of the joint tissues. Even in the absence of injury, joint tissues have adaptive responses to processes, like aging and menopause, which result in changes to the set point. Purpose The purpose of this study in a preclinical model was to investigate age-related and menopause-related changes in knee-joint tissues with the hypothesis that tissues will change in unique ways that reflect their differing contributions to maintaining joint function (as measured by joint laxity) and the differing processes of aging and menopause. Methods Rabbit knee-joint tissues from three groups were evaluated: young adult (gene expression, n=8; joint laxity, n=7; water content, n=8), aging adult (gene expression, n=6; joint laxity, n=7; water content, n=5), and menopausal adult (gene expression, n=8; joint laxity, n=7; water content, n=8). Surgical menopause was induced with ovariohysterectomy surgery and gene expression was assessed using reverse-transcription quantitative polymerase chain reaction. Results Aging resulted in changes to 37 of the 150 gene–tissue combinations evaluated, and menopause resulted in changes to 39 of the 150. Despite the similar number of changes, only eleven changes were the same in both aging and menopause. No differences in joint laxity were detected comparing young adult rabbits with aging adult rabbits or with menopausal adult rabbits. Conclusion Aging and menopause affected the gene-expression patterns of the tissues of the knee joint differently, suggesting unique changes to the set point of the knee. Interestingly, aging and menopause did not affect knee-joint laxity, suggesting that joint function was maintained, despite changes in gene expression. Taken together, these findings support the theory of the joint as an organ where the tissues of the joint adapt to

Mechanical Behavior of Dowel-Type Joints Made of Wood Scrimber Composite

PubMed Central

He, Minjuan; Tao, Duo; Li, Zheng; Li, Maolin

2016-01-01

As a renewable building material with low embodied energy characteristics, wood has gained more and more attention in the green and sustainable building industry. In terms of material resource and physical properties, scrimber composite not only makes full use of fast-growing wood species, but also has better mechanical performance and less inherent variability than natural wood material. In this study, the mechanical behavior of bolted beam-to-column joints built with a kind of scrimber composite was investigated both experimentally and numerically. Two groups of specimens were tested under monotonic and low frequency cyclic loading protocols. The experimental results showed that the bolted joints built with scrimber composite performed well in initial stiffness, ductility, and energy dissipation. A three-dimensional (3D) non-linear finite element model (FEM) for the bolted beam-to-column joints was then developed and validated by experimental results. The validated model was further used to investigate the failure mechanism of the bolted joints through stress analysis. This study can contribute to the application of the proposed scrimber composite in structural engineering, and the developed FEM can serve as a useful tool to evaluate the mechanical behavior of such bolted beam-to-column joints with different configurations in future research. PMID:28773703

Mechanical Behavior of Dowel-Type Joints Made of Wood Scrimber Composite.

PubMed

He, Minjuan; Tao, Duo; Li, Zheng; Li, Maolin

2016-07-15

As a renewable building material with low embodied energy characteristics, wood has gained more and more attention in the green and sustainable building industry. In terms of material resource and physical properties, scrimber composite not only makes full use of fast-growing wood species, but also has better mechanical performance and less inherent variability than natural wood material. In this study, the mechanical behavior of bolted beam-to-column joints built with a kind of scrimber composite was investigated both experimentally and numerically. Two groups of specimens were tested under monotonic and low frequency cyclic loading protocols. The experimental results showed that the bolted joints built with scrimber composite performed well in initial stiffness, ductility, and energy dissipation. A three-dimensional (3D) non-linear finite element model (FEM) for the bolted beam-to-column joints was then developed and validated by experimental results. The validated model was further used to investigate the failure mechanism of the bolted joints through stress analysis. This study can contribute to the application of the proposed scrimber composite in structural engineering, and the developed FEM can serve as a useful tool to evaluate the mechanical behavior of such bolted beam-to-column joints with different configurations in future research.

Space Suit Joint Torque Testing

NASA Technical Reports Server (NTRS)

Valish, Dana J.

2011-01-01

In 2009 and early 2010, a test was performed to quantify the torque required to manipulate joints in several existing operational and prototype space suits in an effort to develop joint torque requirements appropriate for a new Constellation Program space suit system. The same test method was levied on the Constellation space suit contractors to verify that their suit design meets the requirements. However, because the original test was set up and conducted by a single test operator there was some question as to whether this method was repeatable enough to be considered a standard verification method for Constellation or other future space suits. In order to validate the method itself, a representative subset of the previous test was repeated, using the same information that would be available to space suit contractors, but set up and conducted by someone not familiar with the previous test. The resultant data was compared using graphical and statistical analysis and a variance in torque values for some of the tested joints was apparent. Potential variables that could have affected the data were identified and re-testing was conducted in an attempt to eliminate these variables. The results of the retest will be used to determine if further testing and modification is necessary before the method can be validated.

Materials testing protocol for small joint prostheses.

PubMed

Savory, K M; Hutchinson, D T; Bloebaum, R

1994-10-01

In this article, a protocol for the evaluation of new materials for small joint prostheses is introduced. The testing methods employed in the protocol were developed by reviewing reported clinical failure modes and conditions found in vivo. The methods developed quantitatively evaluates the fatigue, fatigue crack propagation, and wear resistance properties of materials. For this study, a silicone elastomer similar to Dow Corning Silastic HP100, a radiation stable polypropylene, and a copolymer of polypropylene and ethylene propylene-diene monomer (EPDM) are evaluated. None of the materials tested demonstrated the ideal properties that are sought in a self-hinging joint prostheses. The silicone elastomer had excellent wear properties; however, cracks quickly propagated, causing catastrophic failure when fatigued. Conversely, the copolymer showed excellent fatigue crack propagation resistance and less than favorable wear properties. The polypropylene did not perform well in any evaluation.

Emergence of joint attention: relationships between gaze following, social referencing, imitation, and naming in infancy.

PubMed

Slaughter, Virginia; McConnell, Danielle

2003-03-01

The authors investigated the extent to which the joint-attention behaviors of gaze following, social referencing, and object-directed imitation were related to each other and to infants' vocabulary development in a sample of 60 infants between the ages of 8 and 14 months. Joint-attention skills and vocabulary development were assessed in a laboratory setting. Split-half reliability analyses on the joint-attention measures indicated that the tasks reliably assessed infants' capabilities. In the main analysis, no significant correlations were found among the joint-attention behaviors except for a significant relationship between gaze following and the number of names in infants' productive vocabularies. The overall pattern of results did not replicate results of previous studies (e.g., M. Carpenter, K. Nagell, & M. Tomasello, 1998) that found relationships between various emerging joint-attention behaviors.

A Single-Lap Joint Adhesive Bonding Optimization Method Using Gradient and Genetic Algorithms

NASA Technical Reports Server (NTRS)

Smeltzer, Stanley S., III; Finckenor, Jeffrey L.

1999-01-01

A natural process for any engineer, scientist, educator, etc. is to seek the most efficient method for accomplishing a given task. In the case of structural design, an area that has a significant impact on the structural efficiency is joint design. Unless the structure is machined from a solid block of material, the individual components which compose the overall structure must be joined together. The method for joining a structure varies depending on the applied loads, material, assembly and disassembly requirements, service life, environment, etc. Using both metallic and fiber reinforced plastic materials limits the user to two methods or a combination of these methods for joining the components into one structure. The first is mechanical fastening and the second is adhesive bonding. Mechanical fastening is by far the most popular joining technique; however, in terms of structural efficiency, adhesive bonding provides a superior joint since the load is distributed uniformly across the joint. The purpose of this paper is to develop a method for optimizing single-lap joint adhesive bonded structures using both gradient and genetic algorithms and comparing the solution process for each method. The goal of the single-lap joint optimization is to find the most efficient structure that meets the imposed requirements while still remaining as lightweight, economical, and reliable as possible. For the single-lap joint, an optimum joint is determined by minimizing the weight of the overall joint based on constraints from adhesive strengths as well as empirically derived rules. The analytical solution of the sin-le-lap joint is determined using the classical Goland-Reissner technique for case 2 type adhesive joints. Joint weight minimization is achieved using a commercially available routine, Design Optimization Tool (DOT), for the gradient solution while an author developed method is used for the genetic algorithm solution. Results illustrate the critical design variables

Joint ETV/NOWATECH test plan for the Sorbisense GSW40 passive sampler

EPA Science Inventory

The joint test plan is the implementation of a test design developed for verification of the performance of an environmental technology following the NOWATECH ETV method. The verification is a joint verification with the US EPA ETV scheme and the Advanced Monitoring Systems Cent...

Technical tips to perform safe and effective ultrasound guided steroid joint injections in children.

PubMed

Parra, Dimitri A

2015-01-01

The aim of this article is to describe the technique used to perform ultrasound guided steroid joint injections in children in a group of joints that can be injected using ultrasound as the only image guidance modality. The technique is described and didactic figures are provided to illustrate key technical concepts. It is very important to be familiar with the sonographic appearance of the pediatric joints and the developing bone when performing ultrasound-guided joint injections in children.