Classified one-step high-radix signed-digit arithmetic units

Science.gov (United States)

Cherri, Abdallah K.

1998-08-01

High-radix number systems enable higher information storage density, less complexity, fewer system components, and fewer cascaded gates and operations. A simple one-step fully parallel high-radix signed-digit arithmetic is proposed for parallel optical computing based on new joint spatial encodings. This reduces hardware requirements and improves throughput by reducing the space-bandwidth produce needed. The high-radix signed-digit arithmetic operations are based on classifying the neighboring input digit pairs into various groups to reduce the computation rules. A new joint spatial encoding technique is developed to present both the operands and the computation rules. This technique increases the spatial bandwidth product of the spatial light modulators of the system. An optical implementation of the proposed high-radix signed-digit arithmetic operations is also presented. It is shown that our one-step trinary signed-digit and quaternary signed-digit arithmetic units are much simpler and better than all previously reported high-radix signed-digit techniques.

The Cat Is out of the Bag: The Joint Influence of Previous Experience and Looking Behavior on Infant Categorization

Science.gov (United States)

Kovack-Lesh, Kristine A.; Horst, Jessica S.; Oakes, Lisa M.

2008-01-01

We examined the effect of 4-month-old infants' previous experience with dogs, cats, or both and their online looking behavior on their learning of the adult-defined category of "cat" in a visual familiarization task. Four-month-old infants' (N = 123) learning in the laboratory was jointly determined by whether or not they had experience…

Diabetes PSA (:30) Step By Step

Centers for Disease Control (CDC) Podcasts

2009-10-24

First steps to preventing diabetes. For Hispanic and Latino American audiences.  Created: 10/24/2009 by National Diabetes Education Program (NDEP), a joint program of the Centers for Disease Control and Prevention and the National Institutes of Health.   Date Released: 10/24/2009.

Diabetes PSA (:60) Step By Step

Centers for Disease Control (CDC) Podcasts

2009-10-24

First steps to preventing diabetes. For Hispanic and Latino American audiences.  Created: 10/24/2009 by National Diabetes Education Program (NDEP), a joint program of the Centers for Disease Control and Prevention and the National Institutes of Health.   Date Released: 10/24/2009.

Single-step brazing process for mono-block joints and mechanical testing

Energy Technology Data Exchange (ETDEWEB)

Casalegno, V.; Ferraris, M.; Salvo, M.; Rizzo, S. [Politecnico di Torino, Materials Science and Chemical Engineering Dept., Torino (Italy); Merola, M. [ITER International Team, llER Joint Work Site, Cadarache, 13 - St Paul Lez Durance (France)

2007-07-01

Full text of publication follows: Plasma facing components act as actively cooled thermal shields to sustain thermal and particle loads during normal and transient operations in ITER (International Thermonuclear Experimental Reactor). The plasma-facing layer is referred to as 'armour', which is made of either carbon fibre reinforced carbon composite (CFC) or tungsten (W). CFC is the reference design solution for the lower part of the vertical target of the ITER divertor. The armour is joined onto an actively cooled substrate, the heat sink, made of precipitation hardened copper alloy CuCrZr through a thin pure copper interlayer to decrease, by plastic deformation, the joint interface stresses; in fact, the CFC to Cu joint is affected by the CTE mismatch between the ceramic and metallic material. A new method of joining CFC to copper and CFC/Cu to CuCrZr alloy was effectively developed for the flat-type configuration; the feasibility of this process also for mono-block geometry and the development of a procedure for testing mono-block-type mock-ups is described in this work. The mono-block configuration consists of copper alloy pipe shielded by CFC blocks. It is worth noting that in mono-block configuration, the large thermal expansion mismatch between CFC and copper alloy is more significant than for flat-tile configuration, due to curved interfaces. The joining technique foresees a single-step brazing process: the brazing of the three materials (CFC-Cu-CuCrZr) can be performed in a single heat treatment using the same Cu/Ge based braze. The composite surface was modified by solid state reaction with chromium with the purpose of increasing the wettability of CFC by the brazing alloy. The CFC substrate reacts with Cr which, forming a carbide layer, allows a large reduction of the contact angle; then, the brazing of CFC to pure copper and pure copper to CuCrZr by the same treatment is feasible. This process allows to obtain good joints using a non

Single-step brazing process for mono-block joints and mechanical testing

International Nuclear Information System (INIS)

Casalegno, V.; Ferraris, M.; Salvo, M.; Rizzo, S.; Merola, M.

2007-01-01

Full text of publication follows: Plasma facing components act as actively cooled thermal shields to sustain thermal and particle loads during normal and transient operations in ITER (International Thermonuclear Experimental Reactor). The plasma-facing layer is referred to as 'armour', which is made of either carbon fibre reinforced carbon composite (CFC) or tungsten (W). CFC is the reference design solution for the lower part of the vertical target of the ITER divertor. The armour is joined onto an actively cooled substrate, the heat sink, made of precipitation hardened copper alloy CuCrZr through a thin pure copper interlayer to decrease, by plastic deformation, the joint interface stresses; in fact, the CFC to Cu joint is affected by the CTE mismatch between the ceramic and metallic material. A new method of joining CFC to copper and CFC/Cu to CuCrZr alloy was effectively developed for the flat-type configuration; the feasibility of this process also for mono-block geometry and the development of a procedure for testing mono-block-type mock-ups is described in this work. The mono-block configuration consists of copper alloy pipe shielded by CFC blocks. It is worth noting that in mono-block configuration, the large thermal expansion mismatch between CFC and copper alloy is more significant than for flat-tile configuration, due to curved interfaces. The joining technique foresees a single-step brazing process: the brazing of the three materials (CFC-Cu-CuCrZr) can be performed in a single heat treatment using the same Cu/Ge based braze. The composite surface was modified by solid state reaction with chromium with the purpose of increasing the wettability of CFC by the brazing alloy. The CFC substrate reacts with Cr which, forming a carbide layer, allows a large reduction of the contact angle; then, the brazing of CFC to pure copper and pure copper to CuCrZr by the same treatment is feasible. This process allows to obtain good joints using a non-active brazing

Joint optimization of algorithmic suites for EEG analysis.

Science.gov (United States)

Santana, Eder; Brockmeier, Austin J; Principe, Jose C

2014-01-01

Electroencephalogram (EEG) data analysis algorithms consist of multiple processing steps each with a number of free parameters. A joint optimization methodology can be used as a wrapper to fine-tune these parameters for the patient or application. This approach is inspired by deep learning neural network models, but differs because the processing layers for EEG are heterogeneous with different approaches used for processing space and time. Nonetheless, we treat the processing stages as a neural network and apply backpropagation to jointly optimize the parameters. This approach outperforms previous results on the BCI Competition II - dataset IV; additionally, it outperforms the common spatial patterns (CSP) algorithm on the BCI Competition III dataset IV. In addition, the optimized parameters in the architecture are still interpretable.

The steps to forming a joint venture IPP in Poland

Energy Technology Data Exchange (ETDEWEB)

Allen, Z.; Colligan, M.J.

1998-07-01

Poland represents the largest market in Central Europe with 38 million people and an installed electrical generating capacity of about 32 gigawatts. Since 1989, when the process of governmental restructuring along free market principals began, the allure to IPP developers has been evident, but is of yet unrealized. The natural model for IPP development in Poland would seem to be joint ventures with Polish generating companies. These enterprises already have sites, franchises, and a going business to contribute to a joint company. There are a number of reasons why so few deals have been concluded in Poland to date, and a number of barriers still exist that tend to hamper the realization of project finance funded power joint ventures. But, these barriers are not insurmountable. Overcoming them in the context of a joint venture relationship with a domestic partner requires patience, work, and an ability to bridge the gaps between the realities of working in a post-Communist environment and the practicalities of structuring projects that can be financed in the international capital markets. The new Energy Law in Poland establishes a framework for a viable private sector power generation business. But the enabling regulations are yet to be published or approved. There is still effective political risk on account of the uncertainty this creates. Pressure is mounting on the Polish Government, especially due to its expressed interest in joining the EU, to get the power sector to operate on private sector terms, if not in private hands. The trends are pointing in the direction of increased market driven policies and practices. The conclusion is that, despite the delays of the past, independent power projects will start to happen in Poland on a joint venture basis, with increasing frequency in the next years.

[The investigation of control mechanisms of stepping rhythm in human in the air-stepping conditions during passive and voluntary leg movements].

Science.gov (United States)

Solopova, I A; Selionon, V A; Grishin, A A

2010-01-01

In unloading condition the degree of activation of the central stepping program was investigated during passive leg movements in healthy subjects, as well as the excitability of spinal motoneurons during passive and voluntary stepping movement. Passive stepping movements with characteristics maximally approximated to those during voluntary stepping were accomplished by experimenter. The comparison of the muscle activity bursts during voluntary and imposed movements was made. In addition to that the influence of artificially created loading onto the foot to the leg movement characteristics was analyzed. Spinal motoneuron excitability was estimated by means of evaluation of amplitude modulation of the soleus H-reflex. The changes of H-reflexes under the fixation of knee or hip joints were also studied. In majority of subjects the passive movements were accompanied by bursts of EMG activity of hip muscles (and sometimes of knee muscles), which timing during step cycle was coincided with burst timing of voluntary step cycle. In many cases the bursts of EMG activity during passive movements exceeded activity in homonymous muscles during voluntary stepping. The foot loading imitation exerted essential influence on distal parts of moving extremity during voluntary as well passive movements, that was expressed in the appearance of movements in the ankle joint and accompanied by emergence and increasing of phasic EMG activity of shank muscles. The excitability of motoneurons during passive movements was greater then during voluntary ones. The changes and modulation of H-reflex throughout the step cycle without restriction of joint mobility and during exclusion of hip joint mobility were similar. The knee joint fixation exerted the greater influence. It is supposed that imposed movements activate the same mechanisms of rhythm generation as a supraspinal commands during voluntary movements. In the conditions of passive movements the presynaptic inhibition depend on afferent

Radiosynoviorthesis of acromioclavicular joint using 169Er-citrate: prospective evaluation of efficacy.

Science.gov (United States)

Vereb, Marika; Liepe, Knut; Fischer, Manfred; Kaliska, Lucia; Noskovicova, Lucia; Balogova, Sona

2018-01-01

There is a clinical need for therapeutic alternative in patients with persisting painful arthritis of AC-joint and failure of previous treatments. However, no radiopharmaceutical is currently explicitly approved for radiosynoviorthesis of acromioclavicular joint. The aim of our study was to prospectively assess the efficacy and safety of radiosynoviorthesis of acromioclavicular joint using erbium-169 citrate. Radiosynoviorthesis of acromioclavicular joint was performed in 51 consecutive patients (18 males, 33 females) mean age 64.3 (range 43.8-82.6, median 63.6) years with clinically confirmed arthritis of 85 acromioclavicular joints. The efficacy of RSO was reported by patients according to 10-step visual analogue scale of pain (VAS) (0 = no pain, 10 = most severe pain) at 6 months after radiosynoviorthesis and by ranking the global therapeutic effect of RSO in 4 categories (1 = the best effect, 4 = no change). To assess the variation of blood perfusion in treated joints, the efficacy of RSO was also evaluated by variation of target (acromioclavicular joint)/non-target (soft tissue) uptake ratio (T/NTR) of metylendiphosphonate (99mTc) measured as number of counts over region of interest on blood pool phase of two-phase bone scintigraphy performed before and 6 months after RSO. Radiosynoviorthesis was followed by significant decrease in VAS, mean - 3.1 (-47%). Excellent, good, moderate and bad response was observed in 57 (67%), 25 (29%), 1 (1%) and in 2 (2%) of acromioclavicular joints respectively. A significant correlation between decrease of T/NTR and variation of VAS in % (ρ = 0.532, p acromioclavicular joint in whom previous line(s) of treatment did not lead to satisfactory pain relief.

Multi-subject Manifold Alignment of Functional Network Structures via Joint Diagonalization.

Science.gov (United States)

Nenning, Karl-Heinz; Kollndorfer, Kathrin; Schöpf, Veronika; Prayer, Daniela; Langs, Georg

2015-01-01

Functional magnetic resonance imaging group studies rely on the ability to establish correspondence across individuals. This enables location specific comparison of functional brain characteristics. Registration is often based on morphology and does not take variability of functional localization into account. This can lead to a loss of specificity, or confounds when studying diseases. In this paper we propose multi-subject functional registration by manifold alignment via coupled joint diagonalization. The functional network structure of each subject is encoded in a diffusion map, where functional relationships are decoupled from spatial position. Two-step manifold alignment estimates initial correspondences between functionally equivalent regions. Then, coupled joint diagonalization establishes common eigenbases across all individuals, and refines the functional correspondences. We evaluate our approach on fMRI data acquired during a language paradigm. Experiments demonstrate the benefits in matching accuracy achieved by coupled joint diagonalization compared to previously proposed functional alignment approaches, or alignment based on structural correspondences.

Frontal joint dynamics when initiating stair ascent from a walk versus a stand.

Science.gov (United States)

Vallabhajosula, Srikant; Yentes, Jennifer M; Stergiou, Nicholas

2012-02-02

Ascending stairs is a challenging activity of daily living for many populations. Frontal plane joint dynamics are critical to understand the mechanisms involved in stair ascension as they contribute to both propulsion and medio-lateral stability. However, previous research is limited to understanding these dynamics while initiating stair ascent from a stand. We investigated if initiating stair ascent from a walk with a comfortable self-selected speed could affect the frontal plane lower-extremity joint moments and powers as compared to initiating stair ascent from a stand and if this difference would exist at consecutive ipsilateral steps on the stairs. Kinematics data using a 3-D motion capture system and kinetics data using two force platforms on the first and third stair treads were recorded simultaneously as ten healthy young adults ascended a custom-built staircase. Data were collected from two starting conditions of stair ascent, from a walk (speed: 1.42 ± 0.21 m/s) and from a stand. Results showed that subjects generated greater peak knee abductor moment and greater peak hip abductor moment when initiating stair ascent from a walk. Greater peak joint moments and powers at all joints were also seen while ascending the second ipsilateral step. Particularly, greater peak hip abductor moment was needed to avoid contact of the contralateral limb with the intermediate step by counteracting the pelvic drop on the contralateral side. This could be important for therapists using stair climbing as a testing/training tool to evaluate hip strength in individuals with documented frontal plane abnormalities (i.e. knee and hip osteoarthritis, ACL injury). Copyright © 2011 Elsevier Ltd. All rights reserved.

Effects of neuromuscular fatigue on perceptual-cognitive skills between genders in the contribution to the knee joint loading during side-stepping tasks.

Science.gov (United States)

Khalid, Abdul Jabbar; Harris, Sujae Ian; Michael, Loke; Joseph, Hamill; Qu, Xingda

2015-01-01

This study investigated whether neuromuscular fatigue affects the neuromuscular control of an athlete within a sports context setting and whether these effects were more pronounced in the females. Lower limb joint kinetics of 6 male and 6 female inter-varsity soccer players performing side-stepping tasks in non-fatigue versus fatigue and anticipated versus unanticipated conditions were quantified using 10 Motion Analysis Corporation cameras and a Kistler(™) force platform. The Yo-Yo intermittent recovery Level 1 fatigue protocol was employed. Stance foot initial contact and peak forces, and peak joint knee moments of the lower limb were submitted to a 3-way mixed-model repeated measure ANOVA. The results suggested that males tend to elicit significantly higher knee joint loadings when fatigued. In addition, males elicited significantly higher peak proximal tibia anterior/posterior shear force, vertical ground reaction force at initial contact and peak internal rotational moments than females. These findings suggested that males were at greater overall injury risk than females, especially in the sagittal plane. Neuromuscular control-based training programmes/interventions that are designed to reduce the risk of the non-contact ACL injury need to be customised for the different genders.

An Investigation into the Relation between the Technique of Movement and Overload in Step Aerobics

Directory of Open Access Journals (Sweden)

Alicja Rutkowska-Kucharska

2017-01-01

Full Text Available The aim of this research was to determine the features of a step workout technique which may be related to motor system overloading in step aerobics. Subjects participating in the research were instructors (n=15 and students (n=15 without any prior experience in step aerobics. Kinematic and kinetic data was collected with the use of the BTS SMART system comprised of 6 calibrated video cameras and two Kistler force plates. The subjects’ task was to perform basic steps. The following variables were analyzed: vertical, anteroposterior, and mediolateral ground reaction forces; foot flexion and abduction and adduction angles; knee joint flexion angle; and trunk flexion angle in the sagittal plane. The angle of a foot adduction recorded for the instructors was significantly smaller than that of the students. The knee joint angle while stepping up was significantly higher for the instructors compared to that for the students. Our research confirmed that foot dorsal flexion and adduction performed while stepping up increased load on the ankle joint. Both small and large angles of knee flexion while stepping up and down resulted in knee joint injuries. A small trunk flexion angle in the entire cycle of step workout shut down dorsal muscles, which stopped suppressing the load put on the spine.

Investigation of displacement, strain and stress in single step transversely isotropic elastic bonded joint

Science.gov (United States)

Apu, Md. Jakaria; Islam, Md. Shahidul

2016-07-01

Bi-material joint is often used in many advanced materials and structures. Determination of the bonding strength at the interface is very difficult because of the presence of the stress singularity. In this paper, the displacement and stress fields of a transversely isotropic bi-material joint around an interface edge are determined. Autodesk Simulation Mechanical 2015 is used to carry out the numerical computations. Stress and displacement fields demonstrate that the values near the edge of joint where the stress singularity occurs are larger than that at the inner portion. From the numerical results, it is suggested that de-bonding of the interface may occur at the interface edge of the joint due to the higher stress concentration at the free edge.

Validation of functional calibration and strap-down joint drift correction for computing 3D joint angles of knee, hip, and trunk in alpine skiing.

Science.gov (United States)

Fasel, Benedikt; Spörri, Jörg; Schütz, Pascal; Lorenzetti, Silvio; Aminian, Kamiar

2017-01-01

To obtain valid 3D joint angles with inertial sensors careful sensor-to-segment calibration (i.e. functional or anatomical calibration) is required and measured angular velocity at each sensor needs to be integrated to obtain segment and joint orientation (i.e. joint angles). Existing functional and anatomical calibration procedures were optimized for gait analysis and calibration movements were impractical to perform in outdoor settings. Thus, the aims of this study were 1) to propose and validate a set of calibration movements that were optimized for alpine skiing and could be performed outdoors and 2) to validate the 3D joint angles of the knee, hip, and trunk during alpine skiing. The proposed functional calibration movements consisted of squats, trunk rotations, hip ad/abductions, and upright standing. The joint drift correction previously proposed for alpine ski racing was improved by adding a second step to reduce separately azimuth drift. The system was validated indoors on a skiing carpet at the maximum belt speed of 21 km/h and for measurement durations of 120 seconds. Calibration repeatability was on average boots. Joint angle precision was <4.9° for all angles and accuracy ranged from -10.7° to 4.2° where the presence of an athlete-specific bias was observed especially for the flexion angle. The improved joint drift correction reduced azimuth drift from over 25° to less than 5°. In conclusion, the system was valid for measuring 3D joint angles during alpine skiing and could be used outdoors. Errors were similar to the values reported in other studies for gait. The system may be well suited for within-athlete analysis but care should be taken for between-athlete analysis because of a possible athlete-specific joint angle bias.

[Bone and joint decade--"mile step" in diagnostics and treatment of movement system diseases?].

Science.gov (United States)

Brongel, Leszek; Lorkowski, Jacek; Hładki, Waldemar; Trybus, Marek

2006-01-01

Musculoskeletal disorders affect hundreds of millions of people across the world and are the most common causes of severe long-term pain and physical disability. The impact from such disorders on the individual and on society let to propose by WHO for the Decade of the Bone and Joint from 2000 to 2010. The goal of the Decade is to improve the health-related quality of life for people with musculoskeletal disorders throughout the world and this could be achieved by raising awareness of the growing burden of bone and joint diseases on society, promoting prevention and treatment and advancing understanding of musculoskeletal disorders through research. The main fields of interest during the Decade are joint diseases, spinal disorders and low back pain, osteoporosis and severe trauma of the extremities. In our Department we study problems concerning on traumatology of old patients, multitrauma injury, biomechanics in spinal disorders, in degenerative joint disease and foot diseases. Apart from contemporary imaging methods like US or CT we use pedobarographic diagnostics and fotogrammetric examination. In this study we present strategic goals and the summary of our ongoing projects in our Department related to the goals of the Bone and Joint Decade.

Association between the gait pattern characteristics of older people and their two-step test scores.

Science.gov (United States)

Kobayashi, Yoshiyuki; Ogata, Toru

2018-04-27

The Two-Step test is one of three official tests authorized by the Japanese Orthopedic Association to evaluate the risk of locomotive syndrome (a condition of reduced mobility caused by an impairment of the locomotive organs). It has been reported that the Two-Step test score has a good correlation with one's walking ability; however, its association with the gait pattern of older people during normal walking is still unknown. Therefore, this study aims to clarify the associations between the gait patterns of older people observed during normal walking and their Two-Step test scores. We analyzed the whole waveforms obtained from the lower-extremity joint angles and joint moments of 26 older people in various stages of locomotive syndrome using principal component analysis (PCA). The PCA was conducted using a 260 × 2424 input matrix constructed from the participants' time-normalized pelvic and right-lower-limb-joint angles along three axes (ten trials of 26 participants, 101 time points, 4 angles, 3 axes, and 2 variable types per trial). The Pearson product-moment correlation coefficient between the scores of the principal component vectors (PCVs) and the scores of the Two-Step test revealed that only one PCV (PCV 2) among the 61 obtained relevant PCVs is significantly related to the score of the Two-Step test. We therefore concluded that the joint angles and joint moments related to PCV 2-ankle plantar-flexion, ankle plantar-flexor moments during the late stance phase, ranges of motion and moments on the hip, knee, and ankle joints in the sagittal plane during the entire stance phase-are the motions associated with the Two-Step test.

Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management. Fourth National Report on Compliance with the Joint Convention Obligations. France

International Nuclear Information System (INIS)

2011-09-01

Environment. Facilities that contain only small amounts of radioactive materials or do not meet the above-mentioned criteria are not subject to any regulatory control in that respect. For her forty report, France drew from the experience it acquired from its participation in the previous meetings on the Joint Convention and the Nuclear Safety Convention. It constitutes a self-supporting report based on existing documentation and reflects the viewpoints of the different actors (regulatory authorities and operators). Hence, for each of the sections in which the regulatory authority is not the only party to express its opinion, a three-step structure was adopted, as follows: - a description by the regulatory authority of the regulations involved; - a presentation by the operators of the steps taken to comply with those regulations, and - an analysis by the regulatory authority of the steps taken by the operators. This report is structured according to the 'guidelines regarding national reports' for the Joint Convention, i.e., an 'article-by-article' format, with each one being addressed in a dedicated section bearing the corresponding text of the relevant article of the Joint Convention on a shaded background at the top of the section. After the Introduction (Section A), the various sections deal successively with the following topics: - Section B Policy and practices under the Joint Convention (Article 32-1); - Section C Scope (Article 3); - Section D Spent-fuel and radioactive-waste inventories, together with the list of the corresponding facilities (Article 32-2); - Section E Legislative and regulatory system in force (Articles 18 to 20); - Section F Other general safety provisions (Articles 21 to 26); - Section G The safety of spent-fuel management (Articles 4 to 10); - Section H The safety of radioactive-waste management (Articles 11 to 17); - Section I Transboundary movements (Article 27); - Section J Disused sealed sources (Article 28), and - Section K Planned safety

Formation of tough composite joints

International Nuclear Information System (INIS)

Brun, M.K.

1997-05-01

Joints which exhibit tough fracture behavior were formed in a composite with a Si/SiC matrix reinforced with Textron SCS-6 fibers with either boron nitride or silicon nitride fiber coatings. In composites with BN coatings fibers were aligned uniaxially, while composites with Si 3 N 4 -coated fibers had a 0/90 degree architecture. Lapped joints (joints with overlapping fingers) were necessary to obtain tough behavior. Geometrical requirements necessary to avoid brittle joint failure have been proposed. Joints with a simple overlap geometry (only a few fingers) would have to be very long in order to prevent brittle failure. Typical failure in these joints is caused by a crack propagating along the interfaces between the joint fingers. Joints of the same overall length, but with geometry changed to be symmetric about the joint centerline and with an extra shear surface exhibited tough fractures accompanied with extensive fiber pullout. The initial matrix cracking of these joints was relatively low because cracks propagated easily through the ends of the fingers. Joints with an optimized stepped sawtooth geometry produced composite-like failures with the stress/strain curves containing an elastic region followed by a region of rising stress with an increase of strain. Increasing the fiber/matrix interfacial strength from 9 to 25 MPa, by changing the fiber coating, increased matrix cracking and ultimate strength of the composite significantly. The best joints had matrix cracking stress and ultimate strength of 138 and 240 MPa, respectively. Joint failure was preceded by multiple matrix cracking in the entire composite. The high strength of the joints will permit building of structures containing joints with only a minor reduction of design stresses

X-ray spectrophotometer SphinX and particle spectrometer STEP-F of the satellite experiment CORONAS-PHOTON. Preliminary results of the joint data analysis

Science.gov (United States)

Dudnik, O. V.; Podgorski, P.; Sylwester, J.; Gburek, S.; Kowalinski, M.; Siarkowski, M.; Plocieniak, S.; Bakala, J.

2012-04-01

A joint analysis is carried out of data obtained with the help of the solar X-ray SphinX spectrophotometer and the electron and proton satellite telescope STEP-F in May 2009 in the course of the scientific space experiment CORONAS-PHOTON. In order to determine the energies and particle types, in the analysis of spectrophotometer records data are used on the intensities of electrons, protons, and secondary γ-radiation, obtained by the STEP-F telescope, which was located in close proximity to the SphinX spectrophotometer. The identical reaction of both instruments is noted at the intersection of regions of the Brazilian magnetic anomaly and the Earth's radiation belts. It is shown that large area photodiodes, serving as sensors of the X-ray spectrometer, reliably record electron fluxes of low and intermediate energies, as well as fluxes of the secondary gamma radiation from construction materials of detector modules, the TESIS instrument complex, and the spacecraft itself. The dynamics of electron fluxes, recorded by the SphinX spectrophotometer in the vicinity of a weak geomagnetic storm, supplements the information about the processes of radial diffusion of electrons, which was studied using the STEP-F telescope.

Fast joint detection-estimation of evoked brain activity in event-related FMRI using a variational approach

Science.gov (United States)

Chaari, Lotfi; Vincent, Thomas; Forbes, Florence; Dojat, Michel; Ciuciu, Philippe

2013-01-01

In standard within-subject analyses of event-related fMRI data, two steps are usually performed separately: detection of brain activity and estimation of the hemodynamic response. Because these two steps are inherently linked, we adopt the so-called region-based Joint Detection-Estimation (JDE) framework that addresses this joint issue using a multivariate inference for detection and estimation. JDE is built by making use of a regional bilinear generative model of the BOLD response and constraining the parameter estimation by physiological priors using temporal and spatial information in a Markovian model. In contrast to previous works that use Markov Chain Monte Carlo (MCMC) techniques to sample the resulting intractable posterior distribution, we recast the JDE into a missing data framework and derive a Variational Expectation-Maximization (VEM) algorithm for its inference. A variational approximation is used to approximate the Markovian model in the unsupervised spatially adaptive JDE inference, which allows automatic fine-tuning of spatial regularization parameters. It provides a new algorithm that exhibits interesting properties in terms of estimation error and computational cost compared to the previously used MCMC-based approach. Experiments on artificial and real data show that VEM-JDE is robust to model mis-specification and provides computational gain while maintaining good performance in terms of activation detection and hemodynamic shape recovery. PMID:23096056

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

Science.gov (United States)

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.

Walking on inclines: how do desert ants monitor slope and step length

Directory of Open Access Journals (Sweden)

Seidl Tobias

2008-06-01

Full Text Available Abstract Background During long-distance foraging in almost featureless habitats desert ants of the genus Cataglyphis employ path-integrating mechanisms (vector navigation. This navigational strategy requires an egocentric monitoring of the foraging path by incrementally integrating direction, distance, and inclination of the path. Monitoring the latter two parameters involves idiothetic cues and hence is tightly coupled to the ant's locomotor behavior. Results In a kinematic study of desert ant locomotion performed on differently inclined surfaces we aimed at pinpointing the relevant mechanisms of estimating step length and inclination. In a behavioral experiment with ants foraging on slippery surfaces we broke the otherwise tightly coupled relationship between stepping frequency and step length and examined the animals' ability to monitor distances covered even under those adverse conditions. We show that the ants' locomotor system is not influenced by inclined paths. After removing the effect of speed, slope had only marginal influence on kinematic parameters. Conclusion From the obtained data we infer that the previously proposed monitoring of angles of the thorax-coxa joint is not involved in inclinometry. Due to the tiny variations in cycle period, we also argue that an efference copy of the central pattern generator coding the step length in its output frequency will most likely not suffice for estimating step length and complementing the pedometer. Finally we propose that sensing forces acting on the ant's legs could provide the desired neuronal correlate employed in monitoring inclination and step length.

Elbow helical axes of motion are not the same in physiologic and kinetic joint simulators.

Science.gov (United States)

Muriuki, Muturi G; Mohagheh-Motlagh, Amin; Smolinski, Patrick J; Miller, Mark Carl

2012-08-31

Physiologic and kinetic joint simulators have been widely used for investigations of joint mechanics. The two types of simulator differ in the way joint motion is achieved; through prescribed motions and/or forces in kinetic joint simulators and by tendon loads in physiologic joint simulators. These two testing modalities have produced important insights, as in elucidating the importance of soft tissue structures to joint stability. However, the equivalence of the modalities has not been tested. This study sequentially tested five cadaveric elbows using both a physiologic simulator and a robot/6DOF system. Using position data from markers on the humerus and ulna, we calculated and compared the helical axes of motion of the specimens as the elbows were flexed from full extension. Six step size increments were used in the helical axis calculation. Marker position data at each test's full extension and full flexion point were also used to calculate a datum (overall) helical axis. The angles between the datum axis and step-wise movements were computed and stored. Increasing step size monotonically decreased the variability and the average conical angle encompassing the helical axes; a repeated measures ANOVA using test type (robot or physiologic simulator) and step size found that both type and step caused statistically significant differences (p<0.001). The large changes in helical axis angle observed for small changes in elbow flexion angle, especially in the robot tests, are a caveat for investigators using similar control algorithms. Controllers may need to include increased joint compliance and/or C(1) continuity to reduce variability. Copyright © 2012 Elsevier Ltd. All rights reserved.

Use of Geodetic Laser Scanning to Evaluate the Curvature of Bedrock Surfaces in an Investigation of Sheeting Joint Formation

Science.gov (United States)

Martel, S. J.; Mitchell, K.

2007-12-01

We are using aerial and tripod-mounted geodetic laser scanning (GLS) data, together with photography and large-scale geologic mapping, to investigate the formation of sheeting joints in Yosemite National Park. Sheeting joints are opening-mode fractures that form subparallel to the topography, and over broad areas in Yosemite they define the bedrock surface. Rock slabs bounded by sheeting joints superficially resemble the layers of an onion. Our hypothesis is that sheeting joints form where a tensile stress normal to the topographic surface exists in the shallow subsurface. This condition is met where k2 P22 + k3 P33 > γ cosβ, where k2 and k3 are the principal curvatures of the bedrock surface, P22 and P33 are the corresponding normal stresses parallel to the principal stresses, γ is the unit weight of the rock, and β is the slope angle. Sheeting joints are predicted where at least one of the principal curvatures is sufficiently convex (negative) and the corresponding normal stress is sufficiently compressive (negative). We use aerial GLS data with a vertical resolution of ~10 cm and a point spacing of ~1 m to measure the slope and curvature of the bedrock surface at the scale of a ridge or valley. We use tripod-mounted GLS data with a point spacing of ~5 cm, large-scale geologic mapping, and photographs to detect steps between consecutive sheeting joints, with the step height giving the sheet joint spacing. Outcrops hosting sheeting joints have a stair-step appearance with a distinctive curvature signature: high convex curvature at the top of a step, and high concave curvature at the step bottom. Steps between sheeting joints with a spacing of less than a meter or so are difficult to detect using the aerial GLS data. Apparently the interpolation of aerial data onto a grid, necessary for our curvature codes, and the smoothing of gridded data to filter out trees compromises the value of the aerial GLS data in detecting the step edges, even though the vertical

Joint Force Quarterly. Issue 57, 2nd Quarter 2010

Science.gov (United States)

2010-04-01

specialized equipment and chemicals.18 While this early work provides a proof of concept, genetic engineering and combinatorial chemistry in the future will...is, entails three steps. Using the reverse planning rubric , the first step is to determine the endstate or goal of joint force development, next

Evaluation of traction stirrup distraction technique to increase the joint space of the shoulder joint in the dog: A cadaveric study.

Science.gov (United States)

Devesa, V; Rovesti, G L; Urrutia, P G; Sanroman, F; Rodriguez-Quiros, J

2015-06-01

The objective of this study was to evaluate technical feasibility and efficacy of a joint distraction technique by traction stirrup to facilitate shoulder arthroscopy and assess potential soft tissue damage. Twenty shoulders were evaluated radiographically before distraction. Distraction was applied with loads from 40 N up to 200 N, in 40 N increments, and the joint space was recorded at each step by radiographic images. The effects of joint flexion and intra-articular air injection at maximum load were evaluated. Radiographic evaluation was performed after distraction to evaluate ensuing joint laxity. Joint distraction by traction stirrup technique produces a significant increase in the joint space; an increase in joint laxity could not be inferred by standard and stress radiographs. However, further clinical studies are required to evaluate potential neurovascular complications. A wider joint space may be useful to facilitate arthroscopy, reducing the likelihood for iatrogenic damage to intra-articular structures. Copyright © 2015 Elsevier Ltd. All rights reserved.

A successful backward step correlates with hip flexion moment of supporting limb in elderly people.

Science.gov (United States)

Takeuchi, Yahiko

2018-01-01

The objective of this study was to determine the positional relationship between the center of mass (COM) and the center of pressure (COP) at the time of step landing, and to examine their relationship with the joint moments exerted by the supporting limb, with regard to factors of the successful backward step response. The study population comprised 8 community-dwelling elderly people that were observed to take successive multi steps after the landing of a backward stepping. Using a motion capture system and force plate, we measured the COM, COP and COM-COP deviation distance on landing during backward stepping. In addition, we measured the moment of the supporting limb joint during backward stepping. The multi-step data were compared with data from instances when only one step was taken (single-step). Variables that differed significantly between the single- and multi-step data were used as objective variables and the joint moments of the supporting limb were used as explanatory variables in single regression analyses. The COM-COP deviation in the anteroposterior was significantly larger in the single-step. A regression analysis with COM-COP deviation as the objective variable obtained a significant regression equation in the hip flexion moment (R2 = 0.74). The hip flexion moment of supporting limb was shown to be a significant explanatory variable in both the PS and SS phases for the relationship with COM-COP distance. This study found that to create an appropriate backward step response after an external disturbance (i.e. the ability to stop after 1 step), posterior braking of the COM by a hip flexion moment are important during the single-limbed standing phase.

An Iterative Ensemble Kalman Filter with One-Step-Ahead Smoothing for State-Parameters Estimation of Contaminant Transport Models

KAUST Repository

Gharamti, M. E.

2015-05-11

The ensemble Kalman filter (EnKF) is a popular method for state-parameters estimation of subsurface flow and transport models based on field measurements. The common filtering procedure is to directly update the state and parameters as one single vector, which is known as the Joint-EnKF. In this study, we follow the one-step-ahead smoothing formulation of the filtering problem, to derive a new joint-based EnKF which involves a smoothing step of the state between two successive analysis steps. The new state-parameters estimation scheme is derived in a consistent Bayesian filtering framework and results in separate update steps for the state and the parameters. This new algorithm bears strong resemblance with the Dual-EnKF, but unlike the latter which first propagates the state with the model then updates it with the new observation, the proposed scheme starts by an update step, followed by a model integration step. We exploit this new formulation of the joint filtering problem and propose an efficient model-integration-free iterative procedure on the update step of the parameters only for further improved performances. Numerical experiments are conducted with a two-dimensional synthetic subsurface transport model simulating the migration of a contaminant plume in a heterogenous aquifer domain. Contaminant concentration data are assimilated to estimate both the contaminant state and the hydraulic conductivity field. Assimilation runs are performed under imperfect modeling conditions and various observational scenarios. Simulation results suggest that the proposed scheme efficiently recovers both the contaminant state and the aquifer conductivity, providing more accurate estimates than the standard Joint and Dual EnKFs in all tested scenarios. Iterating on the update step of the new scheme further enhances the proposed filter’s behavior. In term of computational cost, the new Joint-EnKF is almost equivalent to that of the Dual-EnKF, but requires twice more model

Design of mechanical coxa joints based on three-degree-of-freedom spherical parallel manipulators

International Nuclear Information System (INIS)

Li, Yanbiao; Ji, Shiming; Wang, Zhongfei; Jin, Mingsheng; Liu, Yi; Jin, Zhenlin

2013-01-01

We addressed the issue of the design of mechanical coxa joints based on three-degree-of-freedom spherical parallel manipulators using the parameter statistics optimum method based on index atlases. The coxa joints have the advantages of high payload, high accuracy, and good technological efficiency. The first step of the design and prototyping used in this paper develops the direct and inverse displacement equations from the layout feature of the mechanical coxa joints. Then, the shapes of a constant-orientation workspace of the mechanical coxa joints are described, and the effects of the design parameters on the workspace volume are studied quantitatively. The next step deals with the graphical representation of the atlases that illustrates the relationship between performance evaluation index and design parameters based on the kinematics and torque analysis of the mechanical coxa joints. Finally, the geometric parameters of the coxa joints are obtained by the parameter statistics optimum method based on the index atlases. Considering assembly conditions, the design scheme of the mechanical coxa joints is developed, which provides a theoretical basis for the application of the mechanical coxa joints.

Malalignment at the Lisfranc joint: MR features in asymptomatic patients and cadaveric specimens

Energy Technology Data Exchange (ETDEWEB)

Delfaut, Emmanuelle M. [Radiology Department, Hospital Roger Salengro, CHRU of Lille, Bd du Professeur Jules Leclercq, 59037 Lille Cedex (France); Rosenberg, Zehava Sadka [Radiology Department, Hospital for Joint Diseases, 301 17th East Street, New York, NY 10003 (United States); Demondion, Xavier [Radiology Department, Hospital Roger Salengro, CHRU of Lille, Bd du Professeur Jules Leclercq, 59037 Lille Cedex (France); Anatomy Department, Faculty of Medicine, Place de Verdun, 59037 Lille Cedex (France)

2002-09-01

Abstract Objective. To assess the frequency of malalignment in the 1st, 2nd and 3rd tarso-metatarsal joints (Lisfranc joint) in cadaveric specimen and asymptomatic individuals utilizing oblique axial MR images.Design and patients. Four fresh frozen cadaveric feet were dissected in the oblique axial plane at 5 mm slice thickness. Thirty MR studies in 29 patients who had no history of pain, trauma or surgery at the tarso-metatarsal area were included in our study. The 1st to 3rd tarso-metatarsal joints were evaluated on the MR studies and cadaveric slices by two musculoskeletal radiologists for (1) the presence of a medial and/or lateral step-off and (2) articular surface divergence.Results. In the cadaveric dissections there were lateral step-offs in the 1st (n=3) and in the 2nd ray (n=3) respectively. No joint incongruity was evidenced. The MR studies in the patients population depicted 28 step-offs (9 medial, 19 lateral) in the 1st ray, 16 (2 medial, 14 lateral) in the 2nd ray and two in the 3rd ray. Joint incongruity was present in the 2nd ray (n=6) and in the 3rd ray (n=12). All the above findings were limited to a few images.Conclusions. Isolated joint malalignment with otherwise normal findings (no ligamentous injury, no fracture and no bone marrow edema) might reflect normal anatomic features at the tarso-metatarsal joints and must be interpreted carefully. (orig.)

Step Cut Lengthening: A Technique for Treatment of Flexor Pollicis Longus Tendon Rupture.

Science.gov (United States)

Chong, Chew-Wei; Chen, Shih-Heng

2018-04-01

Reconstruction of a tendon defect is a challenging task in hand surgery. Delayed repair of a ruptured flexor pollicis longus (FPL) tendon is often associated with tendon defect. Primary repair of the tendon is often not possible, particularly after debridement of the unhealthy segment of the tendon. As such, various surgical treatments have been described in the literature, including single-stage tendon grafting, 2-stage tendon grafting, flexor digitorum superficialis tendon transfer from ring finger, and interphalangeal joint arthrodesis. We describe step cut lengthening of FPL tendon for the reconstruction of FPL rupture. This is a single-stage reconstruction without the need for tendon grafting or tendon transfer. To our knowledge, no such technique has been previously described.

Leakage flow-induced vibration of an eccentric tube-in-tube slip joint

International Nuclear Information System (INIS)

Mulcahy, T.M.

1985-08-01

Eccentricity of a specific slip-joint design separating two cantilevered, telescoping tubes did not create any self-excited lateral vibrations that had not been observed previously for a concentric slip joint. In fact, the eccentricity made instabilities less likely to occur, but only marginally. Most important, design rules previously established to avoid instabilities for the concentric slip joint remain valid for the eccentric slip joint. 6 refs., 9 figs., 2 tabs

Learning dictionaries of sparse codes of 3D movements of body joints for real-time human activity understanding.

Science.gov (United States)

Qi, Jin; Yang, Zhiyong

2014-01-01

Real-time human activity recognition is essential for human-robot interactions for assisted healthy independent living. Most previous work in this area is performed on traditional two-dimensional (2D) videos and both global and local methods have been used. Since 2D videos are sensitive to changes of lighting condition, view angle, and scale, researchers begun to explore applications of 3D information in human activity understanding in recently years. Unfortunately, features that work well on 2D videos usually don't perform well on 3D videos and there is no consensus on what 3D features should be used. Here we propose a model of human activity recognition based on 3D movements of body joints. Our method has three steps, learning dictionaries of sparse codes of 3D movements of joints, sparse coding, and classification. In the first step, space-time volumes of 3D movements of body joints are obtained via dense sampling and independent component analysis is then performed to construct a dictionary of sparse codes for each activity. In the second step, the space-time volumes are projected to the dictionaries and a set of sparse histograms of the projection coefficients are constructed as feature representations of the activities. Finally, the sparse histograms are used as inputs to a support vector machine to recognize human activities. We tested this model on three databases of human activities and found that it outperforms the state-of-the-art algorithms. Thus, this model can be used for real-time human activity recognition in many applications.

Learning dictionaries of sparse codes of 3D movements of body joints for real-time human activity understanding.

Directory of Open Access Journals (Sweden)

Jin Qi

Full Text Available Real-time human activity recognition is essential for human-robot interactions for assisted healthy independent living. Most previous work in this area is performed on traditional two-dimensional (2D videos and both global and local methods have been used. Since 2D videos are sensitive to changes of lighting condition, view angle, and scale, researchers begun to explore applications of 3D information in human activity understanding in recently years. Unfortunately, features that work well on 2D videos usually don't perform well on 3D videos and there is no consensus on what 3D features should be used. Here we propose a model of human activity recognition based on 3D movements of body joints. Our method has three steps, learning dictionaries of sparse codes of 3D movements of joints, sparse coding, and classification. In the first step, space-time volumes of 3D movements of body joints are obtained via dense sampling and independent component analysis is then performed to construct a dictionary of sparse codes for each activity. In the second step, the space-time volumes are projected to the dictionaries and a set of sparse histograms of the projection coefficients are constructed as feature representations of the activities. Finally, the sparse histograms are used as inputs to a support vector machine to recognize human activities. We tested this model on three databases of human activities and found that it outperforms the state-of-the-art algorithms. Thus, this model can be used for real-time human activity recognition in many applications.

Patient gender affects the referral and recommendation for total joint arthroplasty.

Science.gov (United States)

Borkhoff, Cornelia M; Hawker, Gillian A; Wright, James G

2011-07-01

Rates of use of total joint arthroplasty among appropriate and willing candidates are lower in women than in men. A number of factors may explain this gender disparity, including patients' preferences for surgery, gender bias influencing physicians' clinical decision-making, and the patient-physician interaction. We propose a framework of how patient gender affects the patient and physician decision-making process of referral and recommendation for total joint arthroplasty and consider potential interventions to close the gender gap in total joint arthroplasty utilization. The process involved in the referral and recommendation for total joint arthroplasty involves eight discrete steps. A systematic review is used to describe the influence of patient gender and related clinical and nonclinical factors at each step. WHERE ARE WE NOW?: Patient gender plays an important role in the process of referral and recommendation for total joint arthroplasty. Female gender primarily affects Steps 3 through 8, suggesting barriers unique to women exist in the patient-physician interaction. WHERE DO WE NEED TO GO?: Developing and evaluating interventions that improve the quality of the patient-physician interaction should be the focus of future research. HOW DO WE GET THERE?: Potential interventions include using decision support tools that facilitate shared decision-making between patients and their physicians and promoting cultural competency and shared decision-making skills programs as a core component of medical education. Increasing physicians' acceptance and awareness of the unconscious biases that may be influencing their clinical decision-making may require additional skills programs.

EFFECT OF HEEL LIFTS ON PATELLOFEMORAL JOINT STRESS DURING RUNNING.

Science.gov (United States)

Mestelle, Zachary; Kernozek, Thomas; Adkins, Kelly S; Miller, Jessica; Gheidi, Naghmeh

2017-10-01

Patellofemoral pain is a debilitating injury for many recreational runners. Excessive patellofemoral joint stress may be the underlying source of pain and interventions often focus on ways to reduce patellofemoral joint stress. Heel lifts have been used as an intervention within Achilles tendon rehabilitation programs and to address leg length discrepancies. The purpose of this study was to examine the effect of running with heel lifts on patellofemoral joint stress, patellofemoral stress impulse, quadriceps force, step length, cadence, and other related kinematic and spatiotemporal variables. A repeated-measures research design. Sixteen healthy female runners completed five running trials in a controlled laboratory setting with and without 11mm heel lifts inserted in a standard running shoe. Kinetic and kinematic data were used in combination with a static optimization technique to estimate individual muscle forces. These data were inserted into a patellofemoral joint model which was used to estimate patellofemoral joint stress and other variables during running. When running with heel lifts, peak patellofemoral joint stress and patellofemoral stress impulse were reduced by a 4.2% (p=0.049) and 9.3% (p=0.002). Initial center of pressure was shifted anteriorly 9.1% when running with heel lifts (p0.05) were shown between conditions. Heel lift use resulted in decreased patellofemoral joint stress and impulse without associated changes in step length or frequency, or other variables shown to influence patellofemoral joint stress. The center of pressure at initial contact was also more anterior using heel lifts. The use of heel lifts may have therapeutic benefits for runners with patellofemoral pain if the primary goal is to reduce patellofemoral joint stress. 3b.

Neural network based automated algorithm to identify joint locations on hand/wrist radiographs for arthritis assessment

International Nuclear Information System (INIS)

Duryea, J.; Zaim, S.; Wolfe, F.

2002-01-01

Arthritis is a significant and costly healthcare problem that requires objective and quantifiable methods to evaluate its progression. Here we describe software that can automatically determine the locations of seven joints in the proximal hand and wrist that demonstrate arthritic changes. These are the five carpometacarpal (CMC1, CMC2, CMC3, CMC4, CMC5), radiocarpal (RC), and the scaphocapitate (SC) joints. The algorithm was based on an artificial neural network (ANN) that was trained using independent sets of digitized hand radiographs and manually identified joint locations. The algorithm used landmarks determined automatically by software developed in our previous work as starting points. Other than requiring user input of the location of nonanatomical structures and the orientation of the hand on the film, the procedure was fully automated. The software was tested on two datasets: 50 digitized hand radiographs from patients participating in a large clinical study, and 60 from subjects participating in arthritis research studies and who had mild to moderate rheumatoid arthritis (RA). It was evaluated by a comparison to joint locations determined by a trained radiologist using manual tracing. The success rate for determining the CMC, RC, and SC joints was 87%-99%, for normal hands and 81%-99% for RA hands. This is a first step in performing an automated computer-aided assessment of wrist joints for arthritis progression. The software provides landmarks that will be used by subsequent image processing routines to analyze each joint individually for structural changes such as erosions and joint space narrowing

Osteoblastoma crossing the sacro-iliac joint

Energy Technology Data Exchange (ETDEWEB)

Whittingham-Jones, Paul; Lehovsky, Jan [Royal National Orthopaedic Hospital, Spinal Surgery, London (United Kingdom); Hughes, Richard; Saifuddin, Asif [Royal National Orthopaedic Hospital, Radiology, London (United Kingdom); Fajinmi, Matilda [Royal National Orthopaedic Hospital, Histopathology, London (United Kingdom)

2007-03-15

Osteoblastoma is a rare primary bone tumour which is well-described in the spine and sacrum. We report a case of histologically confirmed osteoblastoma in a 20-year-old male which crossed the sacroiliac joint. This has not previously been described to our knowledge. The imaging features of osteoblastoma and sacroiliac joint involvement by bone tumours are reviewed. (orig.)

A muscle-driven approach to restore stepping with an exoskeleton for individuals with paraplegia.

Science.gov (United States)

Chang, Sarah R; Nandor, Mark J; Li, Lu; Kobetic, Rudi; Foglyano, Kevin M; Schnellenberger, John R; Audu, Musa L; Pinault, Gilles; Quinn, Roger D; Triolo, Ronald J

2017-05-30

Functional neuromuscular stimulation, lower limb orthosis, powered lower limb exoskeleton, and hybrid neuroprosthesis (HNP) technologies can restore stepping in individuals with paraplegia due to spinal cord injury (SCI). However, a self-contained muscle-driven controllable exoskeleton approach based on an implanted neural stimulator to restore walking has not been previously demonstrated, which could potentially result in system use outside the laboratory and viable for long term use or clinical testing. In this work, we designed and evaluated an untethered muscle-driven controllable exoskeleton to restore stepping in three individuals with paralysis from SCI. The self-contained HNP combined neural stimulation to activate the paralyzed muscles and generate joint torques for limb movements with a controllable lower limb exoskeleton to stabilize and support the user. An onboard controller processed exoskeleton sensor signals, determined appropriate exoskeletal constraints and stimulation commands for a finite state machine (FSM), and transmitted data over Bluetooth to an off-board computer for real-time monitoring and data recording. The FSM coordinated stimulation and exoskeletal constraints to enable functions, selected with a wireless finger switch user interface, for standing up, standing, stepping, or sitting down. In the stepping function, the FSM used a sensor-based gait event detector to determine transitions between gait phases of double stance, early swing, late swing, and weight acceptance. The HNP restored stepping in three individuals with motor complete paralysis due to SCI. The controller appropriately coordinated stimulation and exoskeletal constraints using the sensor-based FSM for subjects with different stimulation systems. The average range of motion at hip and knee joints during walking were 8.5°-20.8° and 14.0°-43.6°, respectively. Walking speeds varied from 0.03 to 0.06 m/s, and cadences from 10 to 20 steps/min. A self-contained muscle

Joint refinery selenium treatability study

International Nuclear Information System (INIS)

Meyer, C.L.; Folwarkow, S.

1993-01-01

The San Francisco Regional Water Quality Control Board recently established mass limits on discharges of selenium to the San Francisco Bay from several petroleum refineries. The refineries had been working independently to develop control strategies, including both source control and treatment options, for removal of selenium from their discharges. By January 1992, over fifty different combinations of treatment technologies, wastewater streams, and pretreatment steps had been investigated to determine their effectiveness and feasibility as selenium removal processes. No treatment process studied could achieve the required mass limits without serious negative environmental consequences, such as generation of large amounts of hazardous sludge. To better facilitate the development of a feasible selenium treatment process, the six Bay Area refineries shared results of their studies and identified several technologies that, with further work, could be developed further. This additional work is currently being carried out as part of a joint selenium treatability study sponsored by the Western States Petroleum Association. A review of the previous source control and treatment studies, along with a description of the current treatability studies will be discussed

Handbook on dynamics of jointed structures.

Energy Technology Data Exchange (ETDEWEB)

Ames, Nicoli M.; Lauffer, James P.; Jew, Michael D.; Segalman, Daniel Joseph; Gregory, Danny Lynn; Starr, Michael James; Resor, Brian Ray

2009-07-01

The problem of understanding and modeling the complicated physics underlying the action and response of the interfaces in typical structures under dynamic loading conditions has occupied researchers for many decades. This handbook presents an integrated approach to the goal of dynamic modeling of typical jointed structures, beginning with a mathematical assessment of experimental or simulation data, development of constitutive models to account for load histories to deformation, establishment of kinematic models coupling to the continuum models, and application of finite element analysis leading to dynamic structural simulation. In addition, formulations are discussed to mitigate the very short simulation time steps that appear to be required in numerical simulation for problems such as this. This handbook satisfies the commitment to DOE that Sandia will develop the technical content and write a Joints Handbook. The content will include: (1) Methods for characterizing the nonlinear stiffness and energy dissipation for typical joints used in mechanical systems and components. (2) The methodology will include practical guidance on experiments, and reduced order models that can be used to characterize joint behavior. (3) Examples for typical bolted and screw joints will be provided.

The Non–Symmetric s–Step Lanczos Algorithm: Derivation of Efficient Recurrences and Synchronization–Reducing Variants of BiCG and QMR

Directory of Open Access Journals (Sweden)

Feuerriegel Stefan

2015-12-01

Full Text Available The Lanczos algorithm is among the most frequently used iterative techniques for computing a few dominant eigenvalues of a large sparse non-symmetric matrix. At the same time, it serves as a building block within biconjugate gradient (BiCG and quasi-minimal residual (QMR methods for solving large sparse non-symmetric systems of linear equations. It is well known that, when implemented on distributed-memory computers with a huge number of processes, the synchronization time spent on computing dot products increasingly limits the parallel scalability. Therefore, we propose synchronization-reducing variants of the Lanczos, as well as BiCG and QMR methods, in an attempt to mitigate these negative performance effects. These so-called s-step algorithms are based on grouping dot products for joint execution and replacing time-consuming matrix operations by efficient vector recurrences. The purpose of this paper is to provide a rigorous derivation of the recurrences for the s-step Lanczos algorithm, introduce s-step BiCG and QMR variants, and compare the parallel performance of these new s-step versions with previous algorithms.

Automatic joint alignment measurements from pre- and post-operative long leg standing radiographs

NARCIS (Netherlands)

Goossen, A.; Weber, G.M.; Dries, S.P.M.

2012-01-01

Objectives: For diagnosis or treatment assessment of knee joint osteoarthritis it is required to measure bone morphometry from radiographic images. We propose a method for automatic measurement of joint alignment from pre-operative as well as post-operative radiographs.Methods: In a two step

One step beyond: Different step-to-step transitions exist during continuous contact brachiation in siamangs

Directory of Open Access Journals (Sweden)

Fana Michilsens

2012-02-01

In brachiation, two main gaits are distinguished, ricochetal brachiation and continuous contact brachiation. During ricochetal brachiation, a flight phase exists and the body centre of mass (bCOM describes a parabolic trajectory. For continuous contact brachiation, where at least one hand is always in contact with the substrate, we showed in an earlier paper that four step-to-step transition types occur. We referred to these as a ‘point’, a ‘loop’, a ‘backward pendulum’ and a ‘parabolic’ transition. Only the first two transition types have previously been mentioned in the existing literature on gibbon brachiation. In the current study, we used three-dimensional video and force analysis to describe and characterize these four step-to-step transition types. Results show that, although individual preference occurs, the brachiation strides characterized by each transition type are mainly associated with speed. Yet, these four transitions seem to form a continuum rather than four distinct types. Energy recovery and collision fraction are used as estimators of mechanical efficiency of brachiation and, remarkably, these parameters do not differ between strides with different transition types. All strides show high energy recoveries (mean  = 70±11.4% and low collision fractions (mean  = 0.2±0.13, regardless of the step-to-step transition type used. We conclude that siamangs have efficient means of modifying locomotor speed during continuous contact brachiation by choosing particular step-to-step transition types, which all minimize collision fraction and enhance energy recovery.

Deuterium ingress at rolled joints in Embalse nuclear power plant

International Nuclear Information System (INIS)

Ramos Nervi, J. E.; Schroeter, F.

2013-01-01

Deuterium ingress model at the Rolled Joint has been extensively used for CANDU Nuclear Power Plants Operators in the Life Management of the Pressure Tubes. The importance of understanding the model is vital to avoid delayed hydride cracking at the Rolled Joint. This work reports the first step on develop the model presented on literature to be used in Argentinean CANDU 6, Embalse Nuclear Power Plant. (author)

Preimages for Step-Reduced SHA-2

DEFF Research Database (Denmark)

Aoki, Kazumaro; Guo, Jian; Matusiewicz, Krystian

2009-01-01

In this paper, we present preimage attacks on up to 43-step SHA-256 (around 67% of the total 64 steps) and 46-step SHA-512 (around 57.5% of the total 80 steps), which significantly increases the number of attacked steps compared to the best previously published preimage attack working for 24 steps....... The time complexities are 2^251.9, 2^509 for finding pseudo-preimages and 2^254.9, 2^511.5 compression function operations for full preimages. The memory requirements are modest, around 2^6 words for 43-step SHA-256 and 46-step SHA-512. The pseudo-preimage attack also applies to 43-step SHA-224 and SHA-384...

Failure of the first step of two-stage revision due to polymicrobial prosthetic joint infection of the hip.

Science.gov (United States)

Bozhkova, Svetlana; Tikhilov, Rashid; Labutin, Dmitry; Denisov, Alexey; Shubnyakov, Igor; Razorenov, Vadim; Artyukh, Vasilii; Rukina, Anna

2016-12-01

The unsuccessful treatment of prosthetic joint infection (PJI) with two-stage revision leads to infection recurrence. The objectives of the study were to assess the clinical and demographic characteristics of patients with polymicrobial PJI, and to evaluate the role of the microbial profile involved in PJI in the risk of infection recurrence after the first step of two-stage revision surgery. A retrospective analysis of 189 cases of culture-positive PJI following total hip replacement over a 5-year period was performed. The demographic characteristics of patients, clinical symptoms, microbiology cultures of intraoperative biopsies, laboratory values of C-reactive protein (CRP), white blood cell count and erythrocyte sedimentation rate were analyzed. Patients were divided into two groups-135 with monomicrobial and 54 with polymicrobial infection. Of all patients, 68.9 % in the monomicrobial and 83.3 % in the polymicrobial group had a body mass index >25 kg/m 2 (p = 0.05). The median CRP values were 5.7 mg/L (IQR 4.0-10.0 mg/L) in the monomicrobial compared to 8.8 mg/L (IQR 5.0-27 mg/L) in the polymicrobial group (p = 0.01). The percentage of successful outcomes was 27.8 % in patients with microbial associations (p infection recurrence (OR 4.4; 95 % CI 1.18-16.37; p = 0.03). Overweight and obese patients or those with elevated CRP had a greater risk of polymicrobial PJI. They were predisposed to recurrence of infection after the first step of two-stage revision. An unsuccessful outcome was more likely in cases with polymicrobial infection compared to those with monomicrobial infection. In addition, the presence of multidrug-resistant strains of Gram-negative bacteria substantially increased the risk of PJI treatment being unsuccessful. Level III, therapeutic study.

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

Science.gov (United States)

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.

Interfacial microstructure and mechanical properties of brazed aluminum / stainless steel - joints

Science.gov (United States)

Fedorov, V.; Elßner, M.; Uhlig, T.; Wagner, G.

2017-03-01

Due to the demand of mass and cost reduction, joints based on dissimilar metals become more and more interesting. Especially there is a high interest for joints between stainless steel and aluminum, often necessary for example for automotive heat exchangers. Brazing offers the possibilities to manufacture several joints in one step at, in comparison to fusion welding, lower temperatures. In the recent work, aluminum / stainless steel - joints are produced by induction brazing using an AlSi10 filler and a non-corrosive flux. The mechanical properties are determined by tensile shear tests as well as fatigue tests at ambient and elevated temperatures. The microstructure of the brazed joints and the fracture surfaces of the tested samples are investigated by SEM.

Soft tissue influence on ex vivo mobility in the hip of Iguana: comparison with in vivo movement and its bearing on joint motion of fossil sprawling tetrapods.

Science.gov (United States)

Arnold, Patrick; Fischer, Martin S; Nyakatura, John A

2014-07-01

The reconstruction of a joint's maximum range of mobility (ROM) often is a first step when trying to understand the locomotion of fossil tetrapods. But previous studies suggest that the ROM of a joint is restricted by soft tissues surrounding the joint. To expand the limited informative value of ROM studies for the reconstruction of a fossil species' locomotor characteristics, it is moreover necessary to better understand the relationship of ex vivo ROM with the actual in vivo joint movement. To gain insight into the relationship between ex vivo mobility and in vivo movement, we systematically tested for the influence of soft tissues on joint ROM in the hip of the modern lizard Iguana iguana. Then, we compared the ex vivo mobility to in vivo kinematics of the hip joint in the same specimens using X-ray sequences of steady-state treadmill locomotion previously recorded. With stepwise removal of soft tissues and a repeated-measurement protocol, we show that soft tissues surrounding the hip joint considerably limit ROM, highlighting the problems when joint ROM is deduced from bare bones only. We found the integument to have the largest effect on the range of long-axis rotation, pro- and retraction. Importantly, during locomotion the iguana used only a fragment of the ROM that was measured in our least restrictive dissection situation (i.e. pelvis and femur only conjoined by ligaments), demonstrating the discrepancy between hip joint ROM and actual in vivo movement. Our study emphasizes the necessity for caution when attempting to reconstruct joint ROM or even locomotor kinematics from fossil bones only, as actual in vivo movement cannot be deduced directly from any condition of cadaver mobility in Iguana and likely in other tetrapods. © 2014 Anatomical Society.

A robust and powerful two-step testing procedure for local ancestry adjusted allelic association analysis in admixed populations.

Science.gov (United States)

Duan, Qing; Xu, Zheng; Raffield, Laura M; Chang, Suhua; Wu, Di; Lange, Ethan M; Reiner, Alex P; Li, Yun

2018-04-01

Genetic association studies in admixed populations allow us to gain deeper understanding of the genetic architecture of human diseases and traits. However, population stratification, complicated linkage disequilibrium (LD) patterns, and the complex interplay of allelic and ancestry effects on phenotypic traits pose challenges in such analyses. These issues may lead to detecting spurious associations and/or result in reduced statistical power. Fortunately, if handled appropriately, these same challenges provide unique opportunities for gene mapping. To address these challenges and to take these opportunities, we propose a robust and powerful two-step testing procedure Local Ancestry Adjusted Allelic (LAAA) association. In the first step, LAAA robustly captures associations due to allelic effect, ancestry effect, and interaction effect, allowing detection of effect heterogeneity across ancestral populations. In the second step, LAAA identifies the source of association, namely allelic, ancestry, or the combination. By jointly modeling allele, local ancestry, and ancestry-specific allelic effects, LAAA is highly powerful in capturing the presence of interaction between ancestry and allele effect. We evaluated the validity and statistical power of LAAA through simulations over a broad spectrum of scenarios. We further illustrated its usefulness by application to the Candidate Gene Association Resource (CARe) African American participants for association with hemoglobin levels. We were able to replicate independent groups' previously identified loci that would have been missed in CARe without joint testing. Moreover, the loci, for which LAAA detected potential effect heterogeneity, were replicated among African Americans from the Women's Health Initiative study. LAAA is freely available at https://yunliweb.its.unc.edu/LAAA. © 2017 WILEY PERIODICALS, INC.

Segmentation and measurement of collagen fibers for shoulder and joint therapy studies

Energy Technology Data Exchange (ETDEWEB)

Mascio, L. [Lawrence Livermore National Lab., CA (United States)

1994-11-15

Various shoulder instabilities are debilitating, especially in individuals who perform overhead activities. Thermal modification of soft tissues in joints may allow precise alteration of these tissues` mechanical and/or structural properties to enhance joint function without inducing cell death or an inflammatory response. Several studies have evaluated laser energy for tissue welding. The collective findings are promising, and the next step is to identify the mechanisms responsible for laser-induced capsular tissue alternation, and the short- and long-term effects of non-ablative laser energy on joint capsular tissue. One step toward this goal is to compare the effect of three laser energy densities on the histologic properties of the tissue evaluating the architecture of the collagen (including density, fibril diameter distribution, and interfibrillar space) in sheep at various time intervals after surgery. The specific computer algorithms that are being used to make these measurements will be described.

Modified Labial Button Technique for Maintaining Occlusion After Caudal Mandibular Fracture/Temporomandibular Joint Luxation in the Cat.

Science.gov (United States)

Goodman, Alice E; Carmichael, Daniel T

2016-03-01

Maxillofacial trauma in cats often results in mandibular symphyseal separation in addition to injuries of the caudal mandible and/or temporomandibular joint (TMJ). Caudal mandibular and TMJ injuries are difficult to access and stabilize using direct fixation techniques, thus indirect fixation is commonly employed. The immediate goals of fixation include stabilization for return to normal occlusion and function with the long-term objective of bony union. Indirect fixation techniques commonly used for stabilization of caudal mandibular and temporomandibular joint fracture/luxation include maxillomandibular fixation (MMF) with acrylic composite, interarcade wiring, tape muzzles, and the bignathic encircling and retaining device (BEARD) technique. This article introduces a modification of the previously described "labial reverse suture through buttons" technique used by Koestlin et al and the "labial locking with buttons" technique by Rocha et al. In cases with minimally displaced subcondylar and pericondylar fractures without joint involvement, the labial button technique can provide sufficient stabilization for healing. Advantages of the modified labial button technique include ease of application, noninvasive nature, and use of readily available materials. The construct can remain in place for a variable of amount of time, depending on its intended purpose. It serves as an alternative to the tape muzzle, which is rarely tolerated by cats. This technique can be easily used in conjunction with other maxillomandibular repairs, such as cerclage wire fixation of mandibular symphyseal separation. The purpose of this article is to demonstrate a modified labial button technique for maintaining occlusion of feline caudal mandibular fractures/TMJ luxations in a step-by-step fashion.

Toughness study of an under matched welded joint: application to the mechanical integrity of the electron beam welded joint of 6016-T6 aluminium alloy

International Nuclear Information System (INIS)

Rekik, Wissal

2016-01-01

For the demonstration of the integrity of the most sensitive nuclear components, conventional defects, as cracks for example, must be considered within the design step as required by the nuclear safety authority. This phase is particularly crucial for dimensioning of welded structures. To ensure a conservative prediction, the position of the initial crack within the welded joint must be the most detrimental in fracture behavior. Commonly used analyzes consider homogeneous structure with the behavior of the base metal of the welded joint, considered as the weakest metallurgical zone in the case of an overmatched weld. In contrast, similar analysis is not conservative in case of under matched weld. The thesis contributes by the development of an experimental and numerical methodology allowing the identification of the detrimental metallurgical zone in fracture behavior of an under matched welded joint. The methodology proposed is applied to an electron beam welded joint on al 6061-T6. To reach this goal, the gradient of the mechanical behavior along the welded joint was first identified. This is particularly interesting to conduct an advanced analysis based on a multi material approach. In a second step, the fracture behavior of the welded joint was studied on CT specimen. The transferability of the J integral at initiation was approved on another geometry: this represents an important foundation for the transferability assumption to structure. Finally, a numerical analysis on full scale tube was developed. Residual welding stresses and structural effects were considered. The results demonstrate that the heat affected zone located at 13 mm from the middle of the welded joint is the most detrimental zone for fracture analysis. This contradicts the conventional methods conducted on fracture analysis which consider a conventional defect within the fusion zone. (author) [fr

Study on the thermal-hydraulic stability of high burn up STEP III fuel in Japan

International Nuclear Information System (INIS)

Ishikawa, M.; Kitamura, H.; Toba, A.; Omoto, A.

2004-01-01

Japanese BWR utilities have performed a joint study of the Thermal Hydraulic Stability of High Burn up STEP III Fuel. In this study, the parametric dependency of thermal hydraulic stability threshold was obtained. It was confirmed through experiments that the STEP III Fuel has sufficient stability characteristics. (author)

In vitro V(D)J recombination: signal joint formation.

Science.gov (United States)

Cortes, P; Weis-Garcia, F; Misulovin, Z; Nussenzweig, A; Lai, J S; Li, G; Nussenzweig, M C; Baltimore, D

1996-11-26

The first step of V(D)J recombination, specific cleavage at the recombination signal sequence (RSS), can be carried out by the recombination activating proteins RAG1 and RAG2. In vivo, the cleaved coding and signal ends must be rejoined to generate functional antigen receptors and maintain chromosomal integrity. We have investigated signal joint formation using deletion and inversion substrates in a cell free system. RAG1 and RAG2 alone or in combination were unable to generate signal joints. However, RAG1 and RAG2 complemented with nuclear extracts were able to recombine an extrachromosomal substrate and form precise signal joints. The in vitro reaction resembled authentic V(D)J recombination in being Ku-antigen-dependent.

Biomechanical compensations of the trunk and lower extremities during stepping tasks after unilateral transtibial amputation.

Science.gov (United States)

Murray, Amanda M; Gaffney, Brecca M; Davidson, Bradley S; Christiansen, Cory L

2017-11-01

Lower extremity movement compensations following transtibial amputation are well-documented and are likely influenced by trunk posture and movement. However, the biomechanical compensations of the trunk and lower extremities, especially during high-demand tasks such as step ascent and descent, remain unclear. Kinematic and kinetic data were collected during step ascent and descent tasks for three groups of individuals: diabetic/transtibial amputation, diabetic, and healthy. An ANCOVA was used to compare peak trunk, hip and knee joint angles and moments in the sagittal and frontal planes between groups. Paired t-tests were used to compare peak joint angles and moments between amputated and intact limbs of the diabetic/transtibial amputation group. During step ascent and descent, the transtibial amputation group exhibited greater trunk forward flexion and lateral flexion compared to the other two groups (Pbiomechanical compensations of the trunk and lower extremities in individuals with dysvascular transtibial amputation, by identifying low back, hip, and knee joint moment patterns unique to transtibial amputation during stepping tasks. In addition, the results suggest that some movement compensations may be confounded by the presence of diabetes and precede limb amputation. The increased and asymmetrical loading patterns identified may predispose individuals with transtibial amputation to the development of secondary pain conditions, such as low back pain or osteoarthritis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Binary joint transform correlation using error-diffusion techniques

Science.gov (United States)

Inbar, Hanni; Marom, Emanuel; Konforti, Naim

1993-08-01

Optical pattern recognition techniques based on the optical joint transform correlator (JTC) scheme are attractive due to their simplicity. Recent improvements in spatial light modulators (SLM) increased the popularity of the JTC, providing means for real time operation. Using a binary SLM for the display of the Fourier spectrum, first requires binarization of the joint power spectrum distribution. Although hard-clipping is the simplest and most common binarization method used, we suggest to apply error-diffusion as an improved binarization technique. The performance of a binary JTC, whose input image is considered to contain additive zero-mean white Gaussian noise, is investigated. Various ways for nonlinearly modifying the joint power spectrum prior to the binarization step, which is based on either error-diffusion or hard-clipping techniques, are discussed. These nonlinear modifications aim at increasing the contrast of the interference fringes at the joint power spectrum plane, leading to better definition of the correlation signal. Mathematical analysis, computer simulations and experimental results are presented.

A simplified baseline prediction model for joint damage progression in rheumatoid arthritis: a step toward personalized medicine.

Science.gov (United States)

de Punder, Yvonne M R; van Riel, Piet L C M; Fransen, Jaap

2015-03-01

To compare the performance of an extended model and a simplified prognostic model for joint damage in rheumatoid arthritis (RA) based on 3 baseline risk factors: anticyclic citrullinated peptide antibodies (anti-CCP), erosions, and acute-phase reaction. Data were used from the Nijmegen early RA cohort. An extended model and a simplified baseline prediction model were developed to predict joint damage progression between 0 and 3 years. Joint damage progression was assessed using the Ratingen score. In the extended model, prediction factors were positivity for anti-CCP and/or rheumatoid factor, the level of erythrocyte sedimentation rate, and the quantity of erosions. The prediction score was calculated as the sum of the regression coefficients. In the simplified model, the prediction factors were dichotomized and the number of risk factors was counted. Performances of both models were compared using discrimination and calibration. The models were internally validated using bootstrapping. The extended model resulted in a prediction score between 0 and 5.6 with an area under the receiver-operation characteristic (ROC) curve of 0.77 (95% CI 0.72-0.81). The simplified model resulted in a prediction score between 0 and 3. This model had an area under the ROC curve of 0.75 (95% CI 0.70-0.80). In internal validation, the 2 models showed reasonably well the agreement between observed and predicted probabilities for joint damage progression (Hosmer-Lemeshow test p > 0.05 and calibration slope near 1.0). A simple prediction model for joint damage progression in early RA, by only counting the number of risk factors, has adequate performance. This facilitates the translation of the theoretical prognostic models to daily clinical practice.

Third National Report on compliance with the Joint Convention Obligations

International Nuclear Information System (INIS)

2008-09-01

The Joint Convention on the Safety of Spent Fuel Management and the Safety of Radioactive Waste Management, hereinafter referred to as the 'Joint Convention', is the result of international discussions that followed the adoption of the Convention on Nuclear Safety, in 1994. France signed the Joint Convention at the General Conference of the International Atomic Energy Agency (IAEA) held on 29 September 1997, the very first day the Joint Convention was opened for signature. She approved it on 22 February 2000 and filed the corresponding instruments with the IAEA on 27 April 2000. The Joint Convention entered into force on 18 June 2001. For many years, France has been taking an active part in the pursuit of international actions to reinforce nuclear safety and considers the Joint Convention to be a key step in that direction. The fields covered by the Joint Convention have long been part of the French approach to nuclear safety. This report is the third one of its kind. It is published in accordance with Article 32 of the Joint Convention and presents the measures taken by France to meet each of her obligations set out in the Convention. The facilities and the radioactive materials covered by this Convention are quite diversified in nature and are controlled in France by different regulatory authorities. Above a specific threshold of radioactive content, a facility is referred to as a 'basic nuclear facility' (installation nucleaire de base - INB) and placed under the control of the Nuclear Safety Authority (Autorite de surete nucleaire - ASN). Below that threshold and provided that the facility involved is subject to the nomenclature of classified facilities for other purposes than their radioactive materials, any facility may be considered as a 'classified facility on environmental-protection grounds' (installation classee pour la protection de l'environnement - ICPE) and placed under the control of the Ministry for the Environment. Facilities that contain only

Management of lumbar zygapophysial (facet) joint pain

Science.gov (United States)

Manchikanti, Laxmaiah; Hirsch, Joshua A; Falco, Frank JE; Boswell, Mark V

2016-01-01

AIM: To investigate the diagnostic validity and therapeutic value of lumbar facet joint interventions in managing chronic low back pain. METHODS: The review process applied systematic evidence-based assessment methodology of controlled trials of diagnostic validity and randomized controlled trials of therapeutic efficacy. Inclusion criteria encompassed all facet joint interventions performed in a controlled fashion. The pain relief of greater than 50% was the outcome measure for diagnostic accuracy assessment of the controlled studies with ability to perform previously painful movements, whereas, for randomized controlled therapeutic efficacy studies, the primary outcome was significant pain relief and the secondary outcome was a positive change in functional status. For the inclusion of the diagnostic controlled studies, all studies must have utilized either placebo controlled facet joint blocks or comparative local anesthetic blocks. In assessing therapeutic interventions, short-term and long-term reliefs were defined as either up to 6 mo or greater than 6 mo of relief. The literature search was extensive utilizing various types of electronic search media including PubMed from 1966 onwards, Cochrane library, National Guideline Clearinghouse, clinicaltrials.gov, along with other sources including previous systematic reviews, non-indexed journals, and abstracts until March 2015. Each manuscript included in the assessment was assessed for methodologic quality or risk of bias assessment utilizing the Quality Appraisal of Reliability Studies checklist for diagnostic interventions, and Cochrane review criteria and the Interventional Pain Management Techniques - Quality Appraisal of Reliability and Risk of Bias Assessment tool for therapeutic interventions. Evidence based on the review of the systematic assessment of controlled studies was graded utilizing a modified schema of qualitative evidence with best evidence synthesis, variable from level I to level V

Crosslinking of fibrinogen and fibronectin by free radicals : A possible initial step in adhesion formation in osteoarthritis of the temporomandibular joint

NARCIS (Netherlands)

Dijkgraaf, LC; Zardeneta, G; Cordewener, FW; Liem, RSB; Schmitz, JP; de Bont, LGM; Milam, SB

Purpose: Adhesion formation in osteoarthritis (OA) of the temporomandibular joint (TMJ) typically results in a sustained limitation of joint movement. We propose the hypothesis that free-radical-mediated crosslinking of proteins underlies this adhesion formation in affected joints. Free radicals may

The tensile strength of mechanical joint prototype of lontar fiber composite

Science.gov (United States)

Bale, Jefri; Adoe, Dominggus G. H.; Boimau, Kristomus; Sakera, Thomas

2018-03-01

In the present study, an experimental activity has been programmed to investigate the effect of joint prototype configuration on tensile strength of lontar (Borassus Flabellifer) fiber composite. To do so, a series of tests were conducted to establish the tensile strength of different joint prototype configuration specimen of lontar fiber composite. In addition, post observation of macroscope was used to map damage behavior. The analysis of lontar fiber composite is a challenge since the material has limited information than others natural fiber composites materials. The results shown that, under static tensile loading, the tensile strength of 13 MPa produced by single lap joint of lontar fiber composite is highest compare to 11 MPa of tensile strength generated by step lap joint and double lap joint where produced the lowest tensile strength of 6 MPa. It is concluded that the differences of tensile strength depend on the geometric dimensions of the cross-sectional area and stress distribution of each joint prototype configuration.

Space Suit Joint Torque Testing

Science.gov (United States)

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.

MR findings of the temporomandibular joint with crepitus

International Nuclear Information System (INIS)

Sano, Tsukasa; Yamamoto, Mika; Yamaga, Takayoshi; Takahashi, Koji; Masuda, Saeko; Tagaya, Atsuko; Michi, Ken-ichi; Okano, Tomohiro

1997-01-01

Crepitus is an important sign for diagnosis of arthrosis of the temporomandibular joint (TMJ). The presence of crepitus can be evaluated by the listening test previously proposed by our group. However, TMJ can be diagnosed by MR imaging showing the disc position and related findings including bony changes and joint effusion. This study investigated the relationship between the presence of crepitus and pathology of the joint. Fourteen joints with crepitus diagnosed by the listening test were examined in this study. TMJ was categorized into four types based on findings on double spin echo MR images. The results were as follows: Of fourteen joints with crepitus, five (36%) were showed as normal superior disc position. The remaining 9 joints (64%) were diagnosed with disc displacement, of which, 6 showed reduction, one was without reduction and 2 without reduction were associated with arthrosis. Statistical analysis using the data obtained here and other data showed that the joints with crepitus tended to show disk displacement. There was no significant difference between the degree of certainty about the presence of the crepitus and the distribution of joint pathology. Joint effusion was observed only in the joints with displacement. These results indicated that TMJ with crepitus is associated with varied joint pathology. (author)

MR findings of the temporomandibular joint with crepitus

Energy Technology Data Exchange (ETDEWEB)

Sano, Tsukasa; Yamamoto, Mika; Yamaga, Takayoshi; Takahashi, Koji; Masuda, Saeko; Tagaya, Atsuko; Michi, Ken-ichi; Okano, Tomohiro [Showa Univ., Tokyo (Japan). School of Dentistry

1997-06-01

Crepitus is an important sign for diagnosis of arthrosis of the temporomandibular joint (TMJ). The presence of crepitus can be evaluated by the listening test previously proposed by our group. However, TMJ can be diagnosed by MR imaging showing the disc position and related findings including bony changes and joint effusion. This study investigated the relationship between the presence of crepitus and pathology of the joint. Fourteen joints with crepitus diagnosed by the listening test were examined in this study. TMJ was categorized into four types based on findings on double spin echo MR images. The results were as follows: Of fourteen joints with crepitus, five (36%) were showed as normal superior disc position. The remaining 9 joints (64%) were diagnosed with disc displacement, of which, 6 showed reduction, one was without reduction and 2 without reduction were associated with arthrosis. Statistical analysis using the data obtained here and other data showed that the joints with crepitus tended to show disk displacement. There was no significant difference between the degree of certainty about the presence of the crepitus and the distribution of joint pathology. Joint effusion was observed only in the joints with displacement. These results indicated that TMJ with crepitus is associated with varied joint pathology. (author)

Rapid decay of vacancy islands at step edges on Ag(111): step orientation dependence

International Nuclear Information System (INIS)

Shen, Mingmin; Thiel, P A; Jenks, Cynthia J; Evans, J W

2010-01-01

Previous work has established that vacancy islands or pits fill much more quickly when they are in contact with a step edge, such that the common boundary is a double step. The present work focuses on the effect of the orientation of that step, with two possibilities existing for a face centered cubic (111) surface: A- and B-type steps. We find that the following features can depend on the orientation: (1) the shapes of islands while they shrink; (2) whether the island remains attached to the step edge; and (3) the rate of filling. The first two effects can be explained by the different rates of adatom diffusion along the A- and B-steps that define the pit, enhanced by the different filling rates. The third observation-the difference in the filling rate itself-is explained within the context of the concerted exchange mechanism at the double step. This process is facile at all regular sites along B-steps, but only at kink sites along A-steps, which explains the different rates. We also observe that oxygen can greatly accelerate the decay process, although it has no apparent effect on an isolated vacancy island (i.e. an island that is not in contact with a step).

Landmine detection using two-tapped joint orthogonal matching pursuits

Science.gov (United States)

Goldberg, Sean; Glenn, Taylor; Wilson, Joseph N.; Gader, Paul D.

2012-06-01

Joint Orthogonal Matching Pursuits (JOMP) is used here in the context of landmine detection using data obtained from an electromagnetic induction (EMI) sensor. The response from an object containing metal can be decomposed into a discrete spectrum of relaxation frequencies (DSRF) from which we construct a dictionary. A greedy iterative algorithm is proposed for computing successive residuals of a signal by subtracting away the highest matching dictionary element at each step. The nal condence of a particular signal is a combination of the reciprocal of this residual and the mean of the complex component. A two-tap approach comparing signals on opposite sides of the geometric location of the sensor is examined and found to produce better classication. It is found that using only a single pursuit does a comparable job, reducing complexity and allowing for real-time implementation in automated target recognition systems. JOMP is particularly highlighted in comparison with a previous EMI detection algorithm known as String Match.

Joint hypermobility leading to osteoarthrosis and chondrocalcinosis.

Science.gov (United States)

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 Advisory Appeals Board

CERN Multimedia

2004-01-01

The Joint Advisory Appeals Board was convened to examine the appeal lodged by Mrs Maria DIMOU with regard to a periodic one-step increase. As the appellant has not objected, the report of the Board and the final decision of the Director-General are brought to the notice of the personnel in accordance with Article R VI 1.20 of the Staff Regulations. The relevant documents will therefore be posted on the notice boards of the Administration Building (N° 60) from 30 April to 14 May 2004. Human Resources Department Tel. 74128

Joint Advisory Appeals Board

CERN Multimedia

Human Resources Department

2005-01-01

The Joint Advisory Appeals Board was convened to examine an appeal lodged by a member of the personnel with regard to a periodic one-step increase. As the appellant has not objected, the report of the Board and the final decision of the Director-General are brought to the notice of the personnel in accordance with Article R VI 1.20 of the Staff Regulations. The relevant documents will therefore be posted on the notice boards of the Administration Building (N° 60) from 1 to 15 April 2005. Human Resources Department Tel. 74128

Role of step stiffness and kinks in the relaxation of vicinal (001) with zigzag [110] steps

Science.gov (United States)

Mahjoub, B.; Hamouda, Ajmi BH.; Einstein, TL.

2017-08-01

We present a kinetic Monte Carlo study of the relaxation dynamics and steady state configurations of 〈110〉 steps on a vicinal (001) simple cubic surface. This system is interesting because 〈110〉 (fully kinked) steps have different elementary excitation energetics and favor step diffusion more than 〈100〉 (nominally straight) steps. In this study we show how this leads to different relaxation dynamics as well as to different steady state configurations, including that 2-bond breaking processes are rate determining for 〈110〉 steps in contrast to 3-bond breaking processes for 〈100〉-steps found in previous work [Surface Sci. 602, 3569 (2008)]. The analysis of the terrace-width distribution (TWD) shows a significant role of kink-generation-annihilation processes during the relaxation of steps: the kinetic of relaxation, toward the steady state, is much faster in the case of 〈110〉-zigzag steps, with a higher standard deviation of the TWD, in agreement with a decrease of step stiffness due to orientation. We conclude that smaller step stiffness leads inexorably to faster step dynamics towards the steady state. The step-edge anisotropy slows the relaxation of steps and increases the strength of step-step effective interactions.

Joint Chance-Constrained Dynamic Programming

Science.gov (United States)

Ono, Masahiro; Kuwata, Yoshiaki; Balaram, J. Bob

2012-01-01

This paper presents a novel dynamic programming algorithm with a joint chance constraint, which explicitly bounds the risk of failure in order to maintain the state within a specified feasible region. A joint chance constraint cannot be handled by existing constrained dynamic programming approaches since their application is limited to constraints in the same form as the cost function, that is, an expectation over a sum of one-stage costs. We overcome this challenge by reformulating the joint chance constraint into a constraint on an expectation over a sum of indicator functions, which can be incorporated into the cost function by dualizing the optimization problem. As a result, the primal variables can be optimized by a standard dynamic programming, while the dual variable is optimized by a root-finding algorithm that converges exponentially. Error bounds on the primal and dual objective values are rigorously derived. We demonstrate the algorithm on a path planning problem, as well as an optimal control problem for Mars entry, descent and landing. The simulations are conducted using a real terrain data of Mars, with four million discrete states at each time step.

Joint Multi-person Detection and Tracking from Overlapping Cameras

NARCIS (Netherlands)

Liem, M.C.; Gavrila, D.M.

2014-01-01

We present a system to track the positions of multiple persons in a scene from overlapping cameras. The distinguishing aspect of our method is a novel, two-step approach that jointly estimates person position and track assignment. The proposed approach keeps solving the assignment problem tractable,

Real-time visualization of joint cavitation.

Directory of Open Access Journals (Sweden)

Gregory N Kawchuk

Full Text Available Cracking sounds emitted from human synovial joints have been attributed historically to the sudden collapse of a cavitation bubble formed as articular surfaces are separated. Unfortunately, bubble collapse as the source of joint cracking is inconsistent with many physical phenomena that define the joint cracking phenomenon. Here we present direct evidence from real-time magnetic resonance imaging that the mechanism of joint cracking is related to cavity formation rather than bubble collapse. In this study, ten metacarpophalangeal joints were studied by inserting the finger of interest into a flexible tube tightened around a length of cable used to provide long-axis traction. Before and after traction, static 3D T1-weighted magnetic resonance images were acquired. During traction, rapid cine magnetic resonance images were obtained from the joint midline at a rate of 3.2 frames per second until the cracking event occurred. As traction forces increased, real-time cine magnetic resonance imaging demonstrated rapid cavity inception at the time of joint separation and sound production after which the resulting cavity remained visible. Our results offer direct experimental evidence that joint cracking is associated with cavity inception rather than collapse of a pre-existing bubble. These observations are consistent with tribonucleation, a known process where opposing surfaces resist separation until a critical point where they then separate rapidly creating sustained gas cavities. Observed previously in vitro, this is the first in-vivo macroscopic demonstration of tribonucleation and as such, provides a new theoretical framework to investigate health outcomes associated with joint cracking.

Examination of factors affecting gait properties in healthy older adults: focusing on knee extension strength, visual acuity, and knee joint pain.

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Demura, Tomohiro; Demura, Shin-ichi; Uchiyama, Masanobu; Sugiura, Hiroki

2014-01-01

Gait properties change with age because of a decrease in lower limb strength and visual acuity or knee joint disorders. Gait changes commonly result from these combined factors. This study aimed to examine the effects of knee extension strength, visual acuity, and knee joint pain on gait properties of for 181 healthy female older adults (age: 76.1 (5.7) years). Walking speed, cadence, stance time, swing time, double support time, step length, step width, walking angle, and toe angle were selected as gait parameters. Knee extension strength was measured by isometric dynamometry; and decreased visual acuity and knee joint pain were evaluated by subjective judgment whether or not such factors created a hindrance during walking. Among older adults without vision problems and knee joint pain that affected walking, those with superior knee extension strength had significantly greater walking speed and step length than those with inferior knee extension strength (P pain in both knees showed slower walking speed and longer stance time and double support time. A decrease of knee extension strength and visual acuity and knee joint pain are factors affecting gait in the female older adults. Decreased knee extension strength and knee joint pain mainly affect respective distance and time parameters of the gait.

Cinematic study of temporomandibular joint motion using ultra-fast magnetic resonance imaging.

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Manière-Ezvan, A; Havet, T; Franconi, J M; Quémar, J C; de Certaines, J D

1999-10-01

Magnetic Resonance Images (MRI) of the temporomandibular joint (TMJ) are usually performed to study the opening/closing movements of the mandible and have up to now been pseudodynamic step-by-step images simulating condylar motion by post-processing reconstruction. The aim of this study was: 1. to optimize a TMJ cine-imaging method to give a better clinical result than the step-by-step methods; 2. to develop an ultra-fast MRI Gradient Echo (GE) sequence for this purpose; and 3. to analyze condylar movements in the sagittal, coronal and para-axial planes during border mandibular displacements and chewing. Both TM joints were studied in six asymptomatic volunteers. The method involved a compromise between in-plane resolution, slice thickness, signal-to-noise ratio and time resolution. Routine clinical use was found to be a GE pulse sequence providing three images per second with an isometric voxel resolution of approximately two millimeters in ridge. This did not allow visualization of the disk. Using this sequence enabled real and simultaneous condylar displacement observation in the three planes of space and therefore contributed to a better functional diagnosis of pathologic TMJ motions.

Kinematic relationship between rotation of lumbar spine and hip joints during golf swing in professional golfers.

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Mun, Frederick; Suh, Seung Woo; Park, Hyun-Joon; Choi, Ahnryul

2015-05-14

Understanding the kinematics of the lumbar spine and hip joints during a golf swing is a basic step for identifying swing-specific factors associated with low back pain. The objective of this study was to examine the kinematic relationship between rotational movement of the lumbar spine and hip joints during a golf swing. Fifteen professional golfers participated in this study with employment of six infrared cameras to record their golf swings. Anatomical reference system of the upper torso, pelvis and thigh segments, and the location of each hip and knee joint were defined by the protocols of the kinematic model of previous studies. Lumbar spine and hip joint rotational angle was calculated utilizing the Euler angle method. Cross-correlation and angle-angle plot was used to examine the degree of kinematic relationship between joints. A fairly strong coupling relationship was shown between the lumbar spine and hip rotational movements with an average correlation of 0.81. Leading hip contribution to overall rotation was markedly high in the early stage of the downswing, while the lumbar spine contributed greater towards the end of the downswing; however, the relative contributions of the trailing hip and lumbar spine were nearly equal during the entire downswing. Most of the professional golfers participated in this study used a similar coordination strategy when moving their hips and lumbar spine during golf swings. The rotation of hips was observed to be more efficient in producing the overall rotation during the downswing when compared to the backswing. These results provide quantitative information to better understand the lumbar spine and hip joint kinematic characteristics of professional golfers. This study will have great potential to be used as a normal control data for the comparison with kinematic information among golfers with low back pain and for further investigation of golf swing-specific factors associated with injury.

Collaborative models for the joint production of core health technology assessments: negative and positive aspects for the joint work of different European agencies.

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Lo Scalzo, Alessandra; Vicari, Nicola; Corio, Mirella; Perrini, Maria Rosaria; Jefferson, Tom; Gillespie, Francesca; Cerbo, Marina

2014-11-01

The purpose of the European network for Health Technology Assessment (EUnetHTA) is to make HTA agencies collaborate sharing methods and tools thus avoiding duplication of evaluative efforts and allowing resource savings. From 2010 to 2012, the activities of the network were carried out through EUnetHTA Joint Action 1 and Work Package 4 Strand B aimed at producing two Core HTAs with two main objectives: to test the Web based Core model and the collaborative working models. Our objective in this article is to give an historical record of the Work Package activities highlighting what worked and what did not in the collaboration of researchers' groups coming from different agencies. A retrospective description of all the steps for the joint production of the two Core HTAs is provided starting from the first step of selecting technologies of common interest. Primary researchers' views on the whole process have been collected through a semi-structured telephonic interview supported by a questionnaire. Coordinators views were gathered during internal meetings and validated. Majority of respondents thought topic selection procedure was not clear and well managed. About collaborative models, small groups were seen to enable more exchange, whatever the model. According to coordinators, loss of expertise and experience during the production process, different languages, and novelty of the Online Tool were main barriers. Lessons learned from this first experience in Joint Action 1 paved the path for the collaboration in Joint Action 2, as it allowed enhancements and changes in models of collaborations and coordination.

Clinical efficacy of radiation synovectomy in digital joint osteoarthritis

International Nuclear Information System (INIS)

Kampen, Willm Uwe; Hellweg, Leif; Massoudi-Nickel, Schirin; Czech, Norbert; Henze, Eberhard; Brenner, Winfried

2005-01-01

Radiation synovectomy was developed for local treatment of rheumatoid arthritis. In this study, the long-term efficacy of radiation synovectomy was retrospectively evaluated in patients with osteoarthritis (activated arthrosis) of the digital joints using an algofunctional score. Fifty-three digital joints in 29 patients (mean age 64.8 years) were treated by intra-articular injection of 169 Er citrate. All joints were painful despite pharmacotherapy and showed an elevated blood pool pattern in a pretherapeutic three-phase bone scan, indicative for local synovitis. The patients were asked to classify their complaints with respect to different daily manual activities on a ten-step pain scale from 1 (total disability) to 10 (lack of any impairment) prior to and after treatment, with a mean follow-up of 41 months. Local signs of osteoarthritis such as joint swelling or pain were additionally evaluated and were scored from progression of complaints to excellent improvement based on patient self-evaluation. All patients reported a pronounced improvement in their manual activities. The mean total score of 4.73±0.58 for all activities prior to treatment increased significantly to 6.79±0.47 after radiation synovectomy (p<0.05). The best results were obtained in the thumb base joints, whereas distal interphalangeal joints were frequently resistant to therapy. Radiation synovectomy is highly effective in digital joint osteoarthritis with concomitant local synovitis. (orig.)

Clinical efficacy of radiation synovectomy in digital joint osteoarthritis

Energy Technology Data Exchange (ETDEWEB)

Kampen, Willm Uwe; Hellweg, Leif; Massoudi-Nickel, Schirin; Czech, Norbert; Henze, Eberhard [University Hospital Schleswig-Holstein, Clinic of Nuclear Medicine, Kiel (Germany); Brenner, Winfried [University Hospital Hamburg-Eppendorf, Department of Nuclear Medicine (Germany)

2005-04-01

Radiation synovectomy was developed for local treatment of rheumatoid arthritis. In this study, the long-term efficacy of radiation synovectomy was retrospectively evaluated in patients with osteoarthritis (activated arthrosis) of the digital joints using an algofunctional score. Fifty-three digital joints in 29 patients (mean age 64.8 years) were treated by intra-articular injection of{sup 169}Er citrate. All joints were painful despite pharmacotherapy and showed an elevated blood pool pattern in a pretherapeutic three-phase bone scan, indicative for local synovitis. The patients were asked to classify their complaints with respect to different daily manual activities on a ten-step pain scale from 1 (total disability) to 10 (lack of any impairment) prior to and after treatment, with a mean follow-up of 41 months. Local signs of osteoarthritis such as joint swelling or pain were additionally evaluated and were scored from progression of complaints to excellent improvement based on patient self-evaluation. All patients reported a pronounced improvement in their manual activities. The mean total score of 4.73{+-}0.58 for all activities prior to treatment increased significantly to 6.79{+-}0.47 after radiation synovectomy (p<0.05). The best results were obtained in the thumb base joints, whereas distal interphalangeal joints were frequently resistant to therapy. Radiation synovectomy is highly effective in digital joint osteoarthritis with concomitant local synovitis. (orig.)

Homogeneity and Strength of Mortar Joints in Pearl-Chain Bridges

DEFF Research Database (Denmark)

Lund, Mia Schou Møller; Arvidsson, Michael; Hansen, Kurt Kielsgaard

2015-01-01

-to-mix mortar products are tested. To the authors’ knowledge, no previous published work has documented the homogeneity and properties of mortar joints of such a height. Hence, the present study documents a practical test procedure where the homogeneity of three mortar joints measuring 20 x 220 x 2400 mm has...

Finite element analysis of elasto-plastic tee joints

International Nuclear Information System (INIS)

Powell, G.H.

1974-09-01

The theory and computational procedures used in the computer program B169TJ/EP for the analysis of elasto-plastic tee joints are described, and detailed user's guide is presented. The program is particularly applicable to joints conforming to the ANSI B16.9 Manufacturing Standard, but can also be applied to other joint geometries. The joint may be loaded by internal pressure and by arbitrary combinations of applied forces and moments at the ends of the branch and run pipes, and the loading sequence may be arbitrary. The joint material is assumed to yield according to the von Mises criterion, and to exhibit either linear kinematic hardening or nonlinear isotropic hardening after yield. The program makes use of the finite element and mesh generation procedures previously applied in the elastic stress analysis program B16.9TJ/ SA, with minor modifications. (U.S.)

Hip joint mobility in dancers: preliminary report.

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Drężewska, Marlena; Gałuszka, Renata; Sliwiński, Zbigniew

2012-01-01

The aim of this study was to evaluate the impact of dancing on hip joint mobility and to assess the relationship between active movements of the hips and injuries among dancers, which may be important in planning rehabilitation in this group. The sample comprised 49 dancers (37 women and 12 men) aged 15 to 32 years. The participants were the professional dancers of the Kielce Dance Theatre and members of two youth jazz dance teams from the Kielce Dance Theatre. The active range of motion of the hips was measured in three planes using a goniometer in order to assess the influence of dance training on hip joint mobility. A questionnaire-based survey was also conducted. The range of flexion, extension and external rotation was significantly greater in the group of long-time dancers (p <0.05). There was a significantly greater range of flexion, abduction and external rotation in previously injured hip joints (p<0.05). 1. Injuries to hip joints in dancers may result in increased ranges of motion, which may lead to disturbances of joint stability. 2. Being a long-time dancer and the female gender were associated with an increased range of hip joint motion.

Foot Placement Characteristics and Plantar Pressure Distribution Patterns during Stepping on Ground in Neonates

Directory of Open Access Journals (Sweden)

F. Sylos-Labini

2017-10-01

Full Text Available Stepping on ground can be evoked in human neonates, though it is rather irregular and stereotyped heel-to-toe roll-over pattern is lacking. Such investigations can provide insights into the role of contact- or load-related proprioceptive feedback during early development of locomotion. However, the detailed characteristics of foot placements and their association with motor patterns are still incompletely documented. We elicited stepping in 33 neonates supported on a table. Unilateral limb kinematics, bilateral plantar pressure distribution and EMG activity from up to 11 ipsilateral leg muscles were recorded. Foot placement characteristics in neonates showed a wide variation. In ~25% of steps, the swinging foot stepped onto the contralateral foot due to generally small step width. In the remaining steps with separate foot placements, the stance phase could start with forefoot (28%, midfoot (47%, or heel (25% touchdowns. Despite forefoot or heel initial contacts, the kinematic and loading patterns markedly differed relatively to toe-walking or adult-like two-peaked vertical force profile. Furthermore, while the general stepping parameters (cycle duration, step length, range of motion of proximal joints were similar, the initial foot contact was consistently associated with specific center-of-pressure excursion, range of motion in the ankle joint, and the center-of-activity of extensor muscles (being shifted by ~5% of cycle toward the end of stance in the “heel” relative to “forefoot” condition. In sum, we found a variety of footfall patterns in conjunction with associated changes in motor patterns. These findings suggest the potential contribution of load-related proprioceptive feedback and/or the expression of variations in the locomotor program already during early manifestations of stepping on ground in human babies.

Determination of the step dipole moment and the step line tension on Ag(0 0 1) electrodes

International Nuclear Information System (INIS)

Beltramo, G.L.; Ibach, H.; Linke, U.; Giesen, M.

2008-01-01

Using impedance spectroscopy, we determined the step dipole moment and the potential dependence of the step line tension of silver electrodes in contact with an electrolyte: (0 0 1) and vicinal surfaces (1 1 n) with n = 5, 7, 11 in 10 mM ClO 4 - -solutions were investigated. The step dipole moment is determined from the shift of the potential of zero charge (pzc) as a function of the surface step density. The dipole moment per step atom was found to be 3.5 ± 0.5 x 10 -3 e A. From the pzc and the potential dependence of the capacitance curves, the potential dependence of the surface tension of the vicinal surfaces is determined. The line tension of the steps is then calculated from the difference between the surface tensions of stepped (1 1 n) and the nominally step-free (0 0 1) surfaces. The results are compared to a previous study on Au(1 1 n) surfaces. For gold, the step line tension decreases roughly linear with potential, whereas a parabolic shape is observed for silver

Effect of Sacroiliac Joint Manipulation on Selected Gait Parameters in Healthy Subjects.

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Wójtowicz, Sebastian; Sajko, Igor; Hadamus, Anna; Mosiołek, Anna; Białoszewski, Dariusz

2017-08-31

The sacroiliac joints have complicated biomechanics. While the movements in the joints are small, they exert a significant effect on gait. This study aimed to assess how sacroiliac joint manipulation influences selected gait parameters. The study enrolled 57 healthy subjects. The experimental group consisted of 26 participants diagnosed with dysfunction of one sacroiliac joint. The control group was composed of 31 persons. All subjects from the experimental group underwent sacroiliac joint manipulation. The experimental group showed significant lengthening of the step on both sides and the stride length in this group increased as well. Moreover, the duration of the stride increased (p=0.000826). The maximum midfoot pressure was higher and maximum heel pressure decreased. The differences were statistically significant. 1. Subclinical dysfunctions of the sacroiliac joints may cause functional gait disturbance. 2. Manipulation of the iliosacral joint exerts a significant effect on gait parameters, which may lead to improved gait economy and effec-tiveness. 3. Following manipulation of one iliosacral joint, altered gait parameters are noted on both the manipulated side and the contralateral side, which may translate into improved quality of locomotion.

Joint Exercise Program: DOD Needs to Take Steps to Improve the Quality of Funding Data

Science.gov (United States)

2017-02-01

need to do their due diligence in uploading supporting documentation in order to ensure proper accountability of Combatant Commanders Exercise...Event Life Cycle5 methodology captured and reviewed in JTIMS. Task Performance Observations—which identify whether the training audience achieved the...5The Joint Event Life Cycle comprises the design, planning, preparation, execution

Distinct element modelling of joint behavior in nearfield rock

International Nuclear Information System (INIS)

Hoekmark, H.; Israelsson, J.

1991-09-01

The investigation reported here concerns numerical simulations of the behaviour of the jointed rock mass in the nearest surroundings Of a portion of a KBS3 type tunnel, including one deposition hole. Results from three-dimensional models are presented and compared to results obtained from previous investigations of two-dimensional models. The three-dimensional models and the previous two-dimensional models relate to conditions prevailing in and around the BMT drift in Stripa mine. In particular are the importance of conditions, implicitly assumed in two-dimensional models, regarding joint orientation and joint persistence, investigated. The evaluation of the results is focused on effects on joint apertures. The implications regarding rock permeability is discussed for a couple of cases. It is found that the real three-dimensional geometry is of great importance, and that the two-dimensional models in some cases tend to overestimate the magnitudes of inelastic joint displacements and associated aperture changes considerably, i.e. the real three-dimensional situation implies locking effects, that generally stabilizes the block assembly. It is recommended that further three-dimensional simulations should be performed to determine relevant ranges of alteration of fracture apertures, caused by excavation and thermal processes, and that fracture geometries, that are typical to virgin granitic rock, should be defined and used as input for these simulations. (au)

The physician/hospital joint venture. Developing a win/win strategy for success. Part I: The first step: developing the environment.

Science.gov (United States)

Shorr, A B

1987-02-01

This four part series, "The Physician/Hospital Joint Venture: Developing a Win/Win Strategy," will examine the philosophical basis of marketing to physicians, the options for the organization in formulating a strategy for joint venture development, structuring and negotiating the deal, and finally how to build the physician loyalty and commitment essential for the joint venture's continued success. In this first article, the author emphasizes the organization's need to develop a strategic plan that includes a program for attracting physicians. It also points out the need for sensitivity to physicians' concerns and provides examples of successes and failures.

Prevention of Periprosthetic Joint Infection

Directory of Open Access Journals (Sweden)

Alisina Shahi

2015-04-01

Full Text Available Prosthetic joint infection (PJI is a calamitous complication with high morbidity and substantial cost. The reported incidence is low but it is probably underestimated due to the difficulty in diagnosis. PJI has challenged the orthopaedic community for several years and despite all the advances in this field, it is still a real concern with immense impact on patients, and the healthcare system. Eradication of infection can be very difficult. Therefore, prevention remains the ultimate goal. The medical community has executed many practices with the intention to prevent infection and treat it effectively when it encounters. Numerous factors can predispose patients to PJI. Identifying the host risk factors, patients’ health modification, proper wound care, and optimizing operative room environment remain some of the core fundamental steps that can help minimizing the overall incidence of infection. In this review we have summarized the effective prevention strategies along with the recommendations of a recent International Consensus Meeting on Surgical Site and Periprosthetic Joint Infection.

Computed tomography evaluation of the sacroiliac joints in Crohn disease

International Nuclear Information System (INIS)

Scott, W.W. Jr.; Fishman, E.K.; Kuhlman, J.E.; Caskey, C.I.; O'Brien, J.J.; Walia, G.S.; Bayless, T.M.

1990-01-01

Computed tomography (CT) was used in a prospective study of the sacroiliac joints in 86 patients with Crohn disease to determine the type and frequency of sacroiliac joint abnormalities present in this population. The CT findings were correlated with review of the clinical history in 64 patients. Computed tomography demonstrated changes of sacroiliitis in 29% of the study group. This high prevalence of sacroiliac joint abnormality was found even in those under 30 years of age. It exceeds the 11-19% previously reported from plain film examination, reflecting the greater sensitivity of CT. In the subgroup of 64 patients studied clinically, 19 (30%) had abnormal sacroiliac joints on CT, but only 2 (3%) reported symptoms related to the sacroiliac joints. (orig.)

Immediate effects of a new microprocessor-controlled prosthetic knee joint: a comparative biomechanical evaluation.

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Bellmann, Malte; Schmalz, Thomas; Ludwigs, Eva; Blumentritt, Siegmar

2012-03-01

To investigate the immediate biomechanical effects after transition to a new microprocessor-controlled prosthetic knee joint. Intervention cross-over study with repeated measures. Only prosthetic knee joints were changed. Motion analysis laboratory. Men (N=11; mean age ± SD, 36.7±10.2y; Medicare functional classification level, 3-4) with unilateral transfemoral amputation. Two microprocessor-controlled prosthetic knee joints: C-Leg and a new prosthetic knee joint, Genium. Static prosthetic alignment, time-distance parameters, kinematic and kinetic parameters, and center of pressure. After a half-day training and an additional half-day accommodation, improved biomechanical outcomes were demonstrated by the Genium: lower ground reaction forces at weight acceptance during level walking at various velocities, increased swing phase flexion angles during walking on a ramp, and level walking with small steps. Maximum knee flexion angle during swing phase at various velocities was nearly equal for Genium. Step-over-step stair ascent with the Genium knee was more physiologic as demonstrated by a more equal load distribution between the prosthetic and contralateral sides and a more natural gait pattern. When descending stairs and ramps, knee flexion moments with the Genium tended to increase. During quiet stance on a decline, subjects using Genium accepted higher loading of the prosthetic side knee joint, thus reducing same side hip joint loading as well as postural sway. In comparision to the C-Leg, the Genium demonstrated immediate biomechanical advantages during various daily ambulatory activities, which may lead to an increase in range and diversity of activity of people with above-knee amputations. Results showed that use of the Genium facilitated more natural gait biomechanics and load distribution throughout the affected and sound musculoskeletal structure. This was observed during quiet stance on a decline, walking on level ground, and walking up and down ramps and

SU-F-J-66: Anatomy Deformation Based Comparison Between One-Step and Two-Step Optimization for Online ART

International Nuclear Information System (INIS)

Feng, Z; Yu, G; Qin, S; Li, D; Ma, C; Zhu, J; Yin, Y

2016-01-01

Purpose: This study investigated that how the quality of adapted plan was affected by inter-fractional anatomy deformation by using one-step and two-step optimization for on line adaptive radiotherapy (ART) procedure. Methods: 10 lung carcinoma patients were chosen randomly to produce IMRT plan by one-step and two-step algorithms respectively, and the prescribed dose was set as 60 Gy on the planning target volume (PTV) for all patients. To simulate inter-fractional target deformation, four specific cases were created by systematic anatomy variation; including target superior shift 0.5 cm, 0.3cm contraction, 0.3 cm expansion and 45-degree rotation. Based on these four anatomy deformation, adapted plan, regenerated plan and non-adapted plan were created to evaluate quality of adaptation. Adapted plans were generated automatically by using one-step and two-step algorithms respectively to optimize original plans, and regenerated plans were manually created by experience physicists. Non-adapted plans were produced by recalculating the dose distribution based on corresponding original plans. The deviations among these three plans were statistically analyzed by paired T-test. Results: In PTV superior shift case, adapted plans had significantly better PTV coverage by using two-step algorithm compared with one-step one, and meanwhile there was a significant difference of V95 by comparison with adapted and non-adapted plans (p=0.0025). In target contraction deformation, with almost same PTV coverage, the total lung received lower dose using one-step algorithm than two-step algorithm (p=0.0143,0.0126 for V20, Dmean respectively). In other two deformation cases, there were no significant differences observed by both two optimized algorithms. Conclusion: In geometry deformation such as target contraction, with comparable PTV coverage, one-step algorithm gave better OAR sparing than two-step algorithm. Reversely, the adaptation by using two-step algorithm had higher efficiency

SU-F-J-66: Anatomy Deformation Based Comparison Between One-Step and Two-Step Optimization for Online ART

Energy Technology Data Exchange (ETDEWEB)

Feng, Z; Yu, G; Qin, S; Li, D [Shandong Normal University, Jinan, Shandong (China); Ma, C; Zhu, J; Yin, Y [Shandong Cancer Hospital and Institute, Jinan, Shandong (China)

2016-06-15

Purpose: This study investigated that how the quality of adapted plan was affected by inter-fractional anatomy deformation by using one-step and two-step optimization for on line adaptive radiotherapy (ART) procedure. Methods: 10 lung carcinoma patients were chosen randomly to produce IMRT plan by one-step and two-step algorithms respectively, and the prescribed dose was set as 60 Gy on the planning target volume (PTV) for all patients. To simulate inter-fractional target deformation, four specific cases were created by systematic anatomy variation; including target superior shift 0.5 cm, 0.3cm contraction, 0.3 cm expansion and 45-degree rotation. Based on these four anatomy deformation, adapted plan, regenerated plan and non-adapted plan were created to evaluate quality of adaptation. Adapted plans were generated automatically by using one-step and two-step algorithms respectively to optimize original plans, and regenerated plans were manually created by experience physicists. Non-adapted plans were produced by recalculating the dose distribution based on corresponding original plans. The deviations among these three plans were statistically analyzed by paired T-test. Results: In PTV superior shift case, adapted plans had significantly better PTV coverage by using two-step algorithm compared with one-step one, and meanwhile there was a significant difference of V95 by comparison with adapted and non-adapted plans (p=0.0025). In target contraction deformation, with almost same PTV coverage, the total lung received lower dose using one-step algorithm than two-step algorithm (p=0.0143,0.0126 for V20, Dmean respectively). In other two deformation cases, there were no significant differences observed by both two optimized algorithms. Conclusion: In geometry deformation such as target contraction, with comparable PTV coverage, one-step algorithm gave better OAR sparing than two-step algorithm. Reversely, the adaptation by using two-step algorithm had higher efficiency

The mechanics of landing when stepping down in unilateral lower-limb amputees.

Science.gov (United States)

Jones, S F; Twigg, P C; Scally, A J; Buckley, J G

2006-02-01

The ability to successfully negotiate stairs and steps is an important factor for functional independence. While work has been undertaken to understand the biomechanics of gait in lower-limb amputees, little is known about how amputees negotiate stairs and steps. This study aimed to determine the mechanics of landing in unilateral lower-limb amputees when stepping down to a new level. A secondary aim was to assess the effects of using a shank-mounted shock-absorbing device (Tele-Torsion Pylon) on the mechanics of landing. Ten unilateral amputees (five transfemoral and five transtibial) and eight able-bodied controls performed single steps down to a new level (73 and 219 mm). Trials were repeated in amputees with the Tele-Torsion Pylon active and inactive. The mechanics of landing were evaluated by analysing peak limb longitudinal force, maximal limb shortening, lower extremity stiffness, and knee joint angular displacement during the initial contact period, and limb and ankle angle at the instant of ground-contact. Data were collected using a Vicon 3D motion analysis system and two force platforms. Amputees landed on a straightened and near vertical limb. This limb position was maintained in transfemoral amputees, whereas in transtibial amputees knee flexion occurred. As a result lower extremity stiffness was significantly greater in transfemoral amputees compared to transtibial amputees and able-bodied controls (P<0.001). The Tele-Torsion Pylon had little effect on the mechanics of landing in transtibial amputees, but brought about a reduction in lower extremity stiffness in transfemoral amputees (P<0.05). Amputees used a stepping strategy that ensured the direction of the ground reaction force vector was kept anterior of the knee joint centre. Using a Tele-Torsion Pylon may improve the mechanics of landing during downward stepping in transfemoral amputees.

Treadmill walking of the pneumatic biped Lucy: Walking at different speeds and step-lengths

Science.gov (United States)

Vanderborght, B.; Verrelst, B.; Van Ham, R.; Van Damme, M.; Versluys, R.; Lefeber, D.

2008-07-01

Actuators with adaptable compliance are gaining interest in the field of legged robotics due to their capability to store motion energy and to exploit the natural dynamics of the system to reduce energy consumption while walking and running. To perform research on compliant actuators we have built the planar biped Lucy. The robot has six actuated joints, the ankle, knee and hip of both legs with each joint powered by two pleated pneumatic artificial muscles in an antagonistic setup. This makes it possible to control both the torque and the stiffness of the joint. Such compliant actuators are used in passive walkers to overcome friction when walking over level ground and to improve stability. Typically, this kind of robots is only designed to walk with a constant walking speed and step-length, determined by the mechanical design of the mechanism and the properties of the ground. In this paper, we show that by an appropriate control, the robot Lucy is able to walk at different speeds and step-lengths and that adding and releasing weights does not affect the stability of the robot. To perform these experiments, an automated treadmill was built

Multi-joint postural behavior in patients with knee osteoarthritis.

Science.gov (United States)

Turcot, Katia; Sagawa, Yoshimasa; Hoffmeyer, Pierre; Suvà, Domizio; Armand, Stéphane

2015-12-01

Previous studies have demonstrated balance impairment in patients with knee osteoarthritis (OA). Although it is currently accepted that postural control depends on multi-joint coordination, no study has previously considered this postural strategy in patients suffering from knee OA. The objectives of this study were to investigate the multi-joint postural behavior in patients with knee OA and to evaluate the association with clinical outcomes. Eighty-seven patients with knee OA and twenty-five healthy elderly were recruited to the study. A motion analysis system and two force plates were used to investigate the joint kinematics (trunk and lower body segments), the lower body joint moments, the vertical ground reaction force ratio and the center of pressure (COP) during a quiet standing task. Pain, functional capacity and quality of life status were also recorded. Patients with symptomatic and severe knee OA adopt a more flexed posture at all joint levels in comparison with the control group. A significant difference in the mean ratio was found between groups, showing an asymmetric weight distribution in patients with knee OA. A significant decrease in the COP range in the anterior-posterior direction was also observed in the group of patients. Only small associations were observed between postural impairments and clinical outcomes. This study brings new insights regarding the postural behavior of patients with severe knee OA during a quiet standing task. The results confirm the multi-joint asymmetric posture adopted by this population. Copyright © 2014 Elsevier B.V. All rights reserved.

Expansion joints for LMFBR

International Nuclear Information System (INIS)

Dzenus, M.; Hundhausen, W.; Jansing, W.

1980-01-01

This discourse recounts efforts put into the SNR-2 project; specifically the development of compensation devices. The various prototypes of these compensation devices are described and the state of the development reviewed. Large Na (sodium)-heat transfer systems require a lot of valuable space if the component lay-out does not include compensation devices. So, in order to condense the spatial requirement as much as possible, expansion joints must be integrated into the pipe system. There are two basic types to suit the purpose: axial expansion joints and angular expansion joints. The expansion joints were developed on the basis of specific design criteria whereby differentiation is made between expansion joints of small and large nominal diameter. Expansion joints for installation in the sodium-filled primary piping are equipped with safety bellows in addition to the actual working bellows. Expansion joints must be designed and mounted in a manner to completely withstand seismic forces. The design must exclude any damage to the bellows during intermittent operations, that is, when sodium is drained the bellows' folds must be completely empty; otherwise residual solidified sodium could destroy the bellows when restarting. The expansion joints must be engineered on the basis of the following design data for the secondary system of the SNR project: working pressure: 16 bar; failure mode pressure: 5 events; failure mode: 5 sec., 28.5 bar, 520 deg. C; working temperature: 520 deg. C; temperature transients: 30 deg. C/sec.; service life: 200,000 h; number of load cycles: 10 4 ; material: 1.4948 or 1.4919; layer thickness of folds: 0.5 mm; angular deflection (DN 800): +3 deg. C or; axial expansion absorption (DN 600): ±80 mm; calculation: ASME class. The bellows' development work is not handled within this scope. The bellows are supplied by leading manufacturers, and warrant highest quality. Multiple bellows were selected on the basis of maximum elasticity - a property

Space Suit Joint Torque Measurement Method Validation

Science.gov (United States)

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.

Multi-state supernetwork representation and location selection heuristics for two-person joint activity-travel problem

NARCIS (Netherlands)

Liao, F.; Arentze, Theo A.; Timmermans, Harry J P; Leng, Z.; Wang, Y.H.

2014-01-01

Joint travel and joint activity participation by multiple people are common mobility phenomena. The joint scheduling of activities, routes, modes and location choices is a challenging problem due to the explosion of the possible choice combinations. In a previous paper, the authors have suggested an

Management of acromioclavicular joint injuries.

Science.gov (United States)

Li, Xinning; Ma, Richard; Bedi, Asheesh; Dines, David M; Altchek, David W; Dines, Joshua S

2014-01-01

Acromioclavicular joint injuries are among the most common shoulder girdle injuries in athletes and most commonly result from a direct force to the acromion with the arm in an adducted position. Acromioclavicular joint injuries often present with associated injuries to the glenohumeral joint, including an increased incidence of superior labrum anterior posterior (SLAP) tears that may warrant further evaluation and treatment. Anteroposterior stability of the acromioclavicular joint is conferred by the capsule and acromioclavicular ligaments, of which the posterior and superior ligaments are the strongest. Superior-inferior stability is maintained by the coracoclavicular (conoid and trapezoid) ligaments. Type-I or type-II acromioclavicular joint injuries have been treated with sling immobilization, early shoulder motion, and physical therapy, with favorable outcomes. Return to activity can occur when normal shoulder motion and strength are obtained and the shoulder is asymptomatic as compared with the contralateral normal extremity. The management of type-III injuries remains controversial and is individualized. While a return to the previous level of functional activity with nonsurgical treatment has been documented in a number of case series, surgical reduction and coracoclavicular ligament reconstruction has been associated with a favorable outcome and can be considered in patients who place high functional demands on their shoulders or in athletes who participate in overhead sports. Surgical management is indicated for high-grade (≥type IV) acromioclavicular joint injuries to achieve anatomic reduction of the acromioclavicular joint, reconstruction of the coracoclavicular ligaments, and repair of the deltotrapezial fascia. Outcomes after surgical reconstruction of the coracoclavicular ligaments have been satisfactory with regard to achieving pain relief and return to functional activities, but further improvements in the biomechanical strength of these

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

Directory of Open Access Journals (Sweden)

Matalova Eva

2007-12-01

Full Text Available Abstract 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.

Preparatory Body State before Reacting to an Opponent: Short-Term Joint Torque Fluctuation in Real-Time Competitive Sports.

Science.gov (United States)

Fujii, Keisuke; Yamashita, Daichi; Kimura, Tetsuya; Isaka, Tadao; Kouzaki, Motoki

2015-01-01

In a competitive sport, the outcome of a game is determined by an athlete's relationship with an unpredictable and uncontrolled opponent. We have previously analyzed the preparatory state of ground reaction forces (GRFs) dividing non-weighted and weighted states (i.e., vertical GRFs below and above 120% of body weight, respectively) in a competitive ballgame task and demonstrated that the non-weighted state prevented delay of the defensive step and promoted successful guarding. However, the associated kinetics of lower extremity joints during a competitive sports task remains unknown. The present study aims to investigate the kinetic characteristics of a real-time competitive sport before movement initiation. As a first kinetic study on a competitive sport, we initially compared the successful defensive kinetics with a relatively stable preparatory state and the choice-reaction sidestep as a control movement. Then, we investigated the kinetic cause of the outcome in a 1-on-1 dribble in terms of the preparatory states according to our previous study. The results demonstrated that in successful defensive motions in the non-weighted state guarding trial, the times required for the generation of hip abduction and three extension torques for the hip, knee, and ankle joints were significantly shortened compared with the choice-reaction sidestep, and hip abduction and hip extension torques were produced almost simultaneously. The sport-specific movement kinetics emerges only in a more-realistic interactive experimental setting. A comparison of the outcomes in the 1-on-1 dribble and preparatory GRF states showed that, in the non-weighted state, the defenders guarded successfully in 68.0% of the trials, and the defender's initiation time was earlier than that in the weighted state (39.1%). In terms of kinetics, the root mean squares of the derivative of hip abduction and three extension torques in the non-weighted state were smaller than those in the weighted state

Uncertainty, joint uncertainty, and the quantum uncertainty principle

International Nuclear Information System (INIS)

Narasimhachar, Varun; Poostindouz, Alireza; Gour, Gilad

2016-01-01

Historically, the element of uncertainty in quantum mechanics has been expressed through mathematical identities called uncertainty relations, a great many of which continue to be discovered. These relations use diverse measures to quantify uncertainty (and joint uncertainty). In this paper we use operational information-theoretic principles to identify the common essence of all such measures, thereby defining measure-independent notions of uncertainty and joint uncertainty. We find that most existing entropic uncertainty relations use measures of joint uncertainty that yield themselves to a small class of operational interpretations. Our notion relaxes this restriction, revealing previously unexplored joint uncertainty measures. To illustrate the utility of our formalism, we derive an uncertainty relation based on one such new measure. We also use our formalism to gain insight into the conditions under which measure-independent uncertainty relations can be found. (paper)

Do lower-extremity joint dynamics change when stair negotiation is initiated with a self-selected comfortable gait speed?

Science.gov (United States)

Vallabhajosula, Srikant; Yentes, Jennifer M; Momcilovic, Mira; Blanke, Daniel J; Stergiou, Nicholas

2012-02-01

Previous research on the biomechanics of stair negotiation has ignored the effect of the approaching speed. We examined if initiating stair ascent with a comfortable self-selected speed can affect the lower-extremity joint moments and powers as compared to initiating stair ascent directly in front of the stairs. Healthy young adults ascended a custom-built staircase instrumented with force platforms. Kinematics and kinetics data were collected simultaneously for two conditions: starting from farther away and starting in front of the stairs and analyzed at the first and second ipsilateral steps. Results showed that for the first step, participants produced greater peak knee extensor moment, peak hip extensor and flexor moments and peak hip positive power while starting from farther away. Also, for both the conditions combined, participants generated lesser peak ankle plantiflexor, greater peak knee flexor moment, lesser peak ankle negative power and greater peak hip negative power while encountering the first step. These results identify the importance of the starting position in experiments dealing with biomechanics of stair negotiation. Further, these findings have important implications for studying stair ascent characteristics of other populations such as older adults. Copyright © 2011 Elsevier B.V. All rights reserved.

Comparative thermal cyclic test of different beryllium grades previously subjected to simulated disruption loads

International Nuclear Information System (INIS)

Gervash, A.; Giniyatulin, R.; Mazul, I.

1999-01-01

Considering beryllium as plasma facing armour this paper presents recent results obtained in Russia. A special process of joining beryllium to a Cu-alloy material structure is described and recent results of thermal cycling tests of such joints are presented. Summarizing the results, the authors show that a Cu-alloy heat sink structure armoured with beryllium can survive high heat fluxes (≥10 MW/m 2 ) during 1000 heating/cooling cycles without serious damage to the armour material and its joint. The principal feasibility of thermal cycling of beryllium grades and their joints directly in the core of a nuclear reactor is demonstrated and the main results of this test are presented. The paper also describes the thermal cycling of different beryllium grades having cracks initiated by previously applied high heat loads simulating plasma disruptions. (orig.)

An analysis of a joint shear model for jointed media with orthogonal joint sets

International Nuclear Information System (INIS)

Koteras, J.R.

1991-10-01

This report describes a joint shear model used in conjunction with a computational model for jointed media with orthogonal joint sets. The joint shear model allows nonlinear behavior for both joint sets. Because nonlinear behavior is allowed for both joint sets, a great many cases must be considered to fully describe the joint shear behavior of the jointed medium. An extensive set of equations is required to describe the joint shear stress and slip displacements that can occur for all the various cases. This report examines possible methods for simplifying this set of equations so that the model can be implemented efficiently form a computational standpoint. The shear model must be examined carefully to obtain a computationally efficient implementation that does not lead to numerical problems. The application to fractures in rock is discussed. 5 refs., 4 figs

Joint Advisory Appeals Board

CERN Multimedia

HR Department

2008-01-01

The Joint Advisory Appeals Board has examined the internal appeal lodged by a member of the personnel against the decision to grant him only a periodic one-step advancement for the 2006 reference year. The person concerned has not objected to the report of the Board and the final decision of the Director-General being brought to the attention of the members of the personnel. In application of Article R VI 1.18 of the Staff Regulations, these documents will therefore be posted on the notice board of the Main building (bldg. 500) from 1 September to 14 September 2008. Human Resources Department (73911)

Joint Advisory Appeals Board

CERN Multimedia

HR Department

2008-01-01

The Joint Advisory Appeals Board has examined the internal appeal lodged by a member of the personnel with regard to the decision not to award him a periodic one-step advancement for the 2006 reference year. The person concerned has not objected to the report of the Board and the final decision of the Director-General being brought to the notice of the members of the personnel. In application of Article R VI 1.18 of the Staff Regulations, these documents will therefore be posted on the notice board of the Main building (Bldg. 500) from 17 March to 30 March 2008. Human Resources Department Tel. 73911

Joint Advisory Appeals Board

CERN Multimedia

HR Department

2008-01-01

The Joint Advisory Appeals Board has examined the internal appeal lodged by a member of the personnel against the decision to grant him only a periodic one-step advancement for the 2006 reference year. The person concerned has not objected to the report of the Board and the final decision of the Director-General being brought to the attention of the members of the personnel. In application of Article R VI 1.18 of the Staff Regulations, these documents will therefore be posted on the notice board of the Main Building (Bldg. 500) from 1 September to 14 September 2008. Human Resources Department (73911)

Pneumatocysts juxta-articular to the sacroiliac joint

International Nuclear Information System (INIS)

Enzweiler, C.; Loreck, D.; Bollow, M.; Wilhelm, H.; Hamm, B.; Lenk, S.

1998-01-01

Purpose: The purpose of the study was to detect and safely diagnose pneumatocysts by means of computed tomography. Methods: From September 1995 to May 1996 computed tomography of the pelvis was performed in six patients for various indications. A slice thickness of 8 mm was employed for all studies. One patient had undergone surgery for hyperparathyroidism nine years previously. Attenuation values within the coincidentally diagnosed pneumatocysts were obtained. Results: We found a total of 14 pneumatocysts juxtaarticular to the sacroiliac joint. Three patients demonstrated a bilateral intraarticular vacuum phenomenon, yet a joint communication was not found. The lesions did not coincide with inflammation, tumour or trauma. Conclusion: Pneumatocysts are benign bone lesions associated with arthrotic changes of the sacroiliac joint. Computed tomography is the modality of choice for the diagnosis of pneumatocysts. (orig.) [de

A step-by-step guide to systematically identify all relevant animal studies

Science.gov (United States)

Leenaars, Marlies; Hooijmans, Carlijn R; van Veggel, Nieky; ter Riet, Gerben; Leeflang, Mariska; Hooft, Lotty; van der Wilt, Gert Jan; Tillema, Alice; Ritskes-Hoitinga, Merel

2012-01-01

Before starting a new animal experiment, thorough analysis of previously performed experiments is essential from a scientific as well as from an ethical point of view. The method that is most suitable to carry out such a thorough analysis of the literature is a systematic review (SR). An essential first step in an SR is to search and find all potentially relevant studies. It is important to include all available evidence in an SR to minimize bias and reduce hampered interpretation of experimental outcomes. Despite the recent development of search filters to find animal studies in PubMed and EMBASE, searching for all available animal studies remains a challenge. Available guidelines from the clinical field cannot be copied directly to the situation within animal research, and although there are plenty of books and courses on searching the literature, there is no compact guide available to search and find relevant animal studies. Therefore, in order to facilitate a structured, thorough and transparent search for animal studies (in both preclinical and fundamental science), an easy-to-use, step-by-step guide was prepared and optimized using feedback from scientists in the field of animal experimentation. The step-by-step guide will assist scientists in performing a comprehensive literature search and, consequently, improve the scientific quality of the resulting review and prevent unnecessary animal use in the future. PMID:22037056

Step-by-step phacoemulsification training program for ophthalmology residents

Directory of Open Access Journals (Sweden)

Wang Yulan

2013-01-01

Full Text Available Aims: The aim was to analyze the learning curve of phacoemulsification (phaco performed by residents without experience in performing extra-capsular cataract extraction (ECCE in a step-by-step training program (SBSTP. Materials and Methods: Consecutive surgical records of phaco performed from March 2009 to Sept 2011 by four residents without previous ECCE experience were retrospectively reviewed. The completion rate of the first 30 procedures by each resident was calculated. The main intraoperative phaco parameter records for the first 30 surgeries by each resident were compared with those for their last 30 surgeries. Intraoperative complications in the residents′ procedures were also recorded and analyzed. Results: A total of 1013 surgeries were performed by residents. The completion rate for the first 30 phaco procedures was 79.2 μ 5.8%. The main reasons for halting the procedure were as follows: Anterior capsule tear, inability to crack the nucleus, and posterior capsular rupture during phaco or cortex removal. Cumulative dissipated energy of phaco power used during the surgeries was significantly less in the last 30 cases compared with the first 30 cases (30.10 μ 17.58 vs. 55.41 μ 37.59, P = 0.021. Posterior capsular rupture rate was 2.5 μ 1.2% in total (10.8 μ 4.2% in the first 30 cases and 1.7 μ 1.9% in the last 30 cases, P = 0.008; a statistically significant difference. Conclusion:The step-by-step training program might be a necessary process for a resident to transit from dependence to a self-supported operator. It is also an essential middle step between wet lab training to performing the entire phaco procedure on the patient both effectively and safely.

Localized tenosynovial giant cell tumor in both knee joints

International Nuclear Information System (INIS)

Kim, Hyun Su; Kwon, Jong Won; Ahn, Jin Hwan; Chang, Moon Jong; Cho, Eun Yoon

2010-01-01

Tenosynovial giant cell tumor, previously called pigmented villonodular synovitis (PVNS), is a rare benign neoplastic process that may involve the synovium of the joint. The disorder is usually monoarticular and only a few cases have been reported on polyarticular involvement. Herein, we present a case of localized intra-articular tenosynovial giant cell tumor in a 29-year-old man involving both knee joints with a description of the MR imaging and histological findings. (orig.)

Joint Inversion of Vp, Vs, and Resistivity at SAFOD

Science.gov (United States)

Bennington, N. L.; Zhang, H.; Thurber, C. H.; Bedrosian, P. A.

2010-12-01

Seismic and resistivity models at SAFOD have been derived from separate inversions that show significant spatial similarity between the main model features. Previous work [Zhang et al., 2009] used cluster analysis to make lithologic inferences from trends in the seismic and resistivity models. We have taken this one step further by developing a joint inversion scheme that uses the cross-gradient penalty function to achieve structurally similar Vp, Vs, and resistivity images that adequately fit the seismic and magnetotelluric MT data without forcing model similarity where none exists. The new inversion code, tomoDDMT, merges the seismic inversion code tomoDD [Zhang and Thurber, 2003] and the MT inversion code Occam2DMT [Constable et al., 1987; deGroot-Hedlin and Constable, 1990]. We are exploring the utility of the cross-gradients penalty function in improving models of fault-zone structure at SAFOD on the San Andreas Fault in the Parkfield, California area. Two different sets of end-member starting models are being tested. One set is the separately inverted Vp, Vs, and resistivity models. The other set consists of simple, geologically based block models developed from borehole information at the SAFOD drill site and a simplified version of features seen in geophysical models at Parkfield. For both starting models, our preliminary results indicate that the inversion produces a converging solution with resistivity, seismic, and cross-gradient misfits decreasing over successive iterations. We also compare the jointly inverted Vp, Vs, and resistivity models to borehole information from SAFOD to provide a "ground truth" comparison.

Gait analysis and weight bearing in pre-clinical joint pain research.

Science.gov (United States)

Ängeby Möller, Kristina; Svärd, Heta; Suominen, Anni; Immonen, Jarmo; Holappa, Johanna; Stenfors, Carina

2018-04-15

There is a need for better joint pain treatment, but development of new medication has not been successful. Pre-clinical models with readouts that better reflect the clinical situation are needed. In patients with joint pain, pain at rest and pain at walking are two major complaints. We describe a new way of calculating results from gait analysis using the CatWalk™ setup. Rats with monoarthritis induced by injection of Complete Freund's Adjuvant (CFA) intra-articularly into the ankle joint of one hind limb were used to assess gait and dynamic weight bearing. The results show that dynamic weight bearing was markedly reduced for the injected paw. Gait parameters such as amount of normal step sequences, walking speed and duration of step placement were also affected. Treatment with naproxen (an NSAID commonly used for inflammatory pain) attenuated the CFA-induced effects. Pregabalin, which is used for neuropathic pain, had no effect. Reduced dynamic weight bearing during locomotion, assessed and calculated in the way we present here, showed a dose-dependent and lasting normalization after naproxen treatment. In contrast, static weight bearing while standing (Incapacitance tester) showed a significant effect for a limited time only. Mechanical sensitivity (von Frey Optihairs) was completely normalized by naproxen, and the window for testing pharmacological effect disappeared. Objective and reproducible effects, with an endpoint showing face validity compared to pain while walking in patients with joint pain, are achieved by a new way of calculating dynamic weight bearing in monoarthritic rats. Copyright © 2017 Elsevier B.V. All rights reserved.

A One-Step-Ahead Smoothing-Based Joint Ensemble Kalman Filter for State-Parameter Estimation of Hydrological Models

KAUST Repository

El Gharamti, Mohamad; Ait-El-Fquih, Boujemaa; Hoteit, Ibrahim

2015-01-01

The ensemble Kalman filter (EnKF) recursively integrates field data into simulation models to obtain a better characterization of the model’s state and parameters. These are generally estimated following a state-parameters joint augmentation

Increasing the Strength of Adhesively Bonded Joints by Tapering the Adherends

International Nuclear Information System (INIS)

GUESS, TOMMY R.; METZINGER, KURT E.

1999-01-01

Wind turbine blades are often fabricated with composite materials. These composite blades are frequently attached to a metallic structure with an adhesive bond. For the baseline composite-to-steel joint considered in this study, failure typically occurs when the adhesive debonds from the steel adherend. Previous efforts established that the adhesive peel stresses strongly influence the strength of these joints for both single-cycle and fatigue loading. This study focused on reducing the adhesive peel stresses present in these joints by tapering the steel adherends. Several different tapers were evaluated using finite element analysis before arriving at a final design. To confirm that the selected taper was an improvement to the existing design, the baseline joint and the modified joint were tested in both compression and tension. In these axial tests, the compressive strengths of the joints with tapered adherends were greater than those of the baseline joints for both single-cycle and low-cycle fatigue. In addition, only a minor reduction in tensile strength was observed for the joints with tapered adherends when compared to the baseline joints. Thus, the modification would be expected to enhance the overall performance of this joint

Joint implementation - project simulation and organisation. Operationalization of a new instrument of climate policy

International Nuclear Information System (INIS)

Luhmann, H.J.; Ott, H.E.; Beuermann, C.; Fischedick, M.; Hennicke, P.; Bakker, L.

1997-01-01

The study served to analyze the practical aspects of 'Joint Implementation' (JI) under the Framework Convention on Climate Change, in which measures to reduce greenhouse gas emissions are carried out jointly by several countries. As a first step, possible climate protection measures were assessed with respect to their suitability for JI and an overview of suitable JI projects was compiled. In a further step, carried out in cooperation with partners from industry, four specific projects (coal-fired power plant, solar-thermal power plant, cement factory, least-cost planning) were used to simulate JI. In this work, solutions were developed for the calculation of greenhouse gas emissions avoided as well as for project reporting. In addition, proposals were made with respect to the organizational and institutional design on an international JI mechanism. (orig.) [de

Poly-epiphyseal overgrowth: description of a previously unreported skeletal dysplasia

Energy Technology Data Exchange (ETDEWEB)

Pazzaglia, Ugo E.; Bonaspetti, Giovanni [University of Brescia, Orthopaedic Clinic, Brescia (Italy); Beluffi, Giampiero [Fondazione IRCCS Policlinico San Matteo, Department of Paediatric Radiology, Pavia (Italy); Marchi, Antonietta; Bozzola, Mauro; Savasta, Salvatore [Fondazione IRCCS Policlinico San Matteo, Paediatric Clinic, University of Pavia, Pavia (Italy)

2007-10-15

A skeletal dysplasia with previously unreported features is presented. Its evolution was characterized by growth abnormalities of bones without involvement of other organs. Advanced bone age, increased stature and irregular epiphyseal ossification with stippling of the main long bones were documented. Physeal overgrowth was massive in the left proximal humerus and femur. Furthermore, the hip joint appeared fused with an abundant mass of pathological calcific tissue extending from the femur to the ilium. Pathological epiphyses were characterized by anarchic cartilaginous proliferation with multiple ossification centres, while lamellar bone apposition and remodelling were normal. The observed bone changes were different from those in any previously reported syndrome, metabolic defect or bone dysplasia. However, they clearly indicated a defect of endochondral ossification with some resemblance to phenotypes observed in dysplasia epiphysealis hemimelica. (orig.)

Poly-epiphyseal overgrowth: description of a previously unreported skeletal dysplasia

International Nuclear Information System (INIS)

Pazzaglia, Ugo E.; Bonaspetti, Giovanni; Beluffi, Giampiero; Marchi, Antonietta; Bozzola, Mauro; Savasta, Salvatore

2007-01-01

A skeletal dysplasia with previously unreported features is presented. Its evolution was characterized by growth abnormalities of bones without involvement of other organs. Advanced bone age, increased stature and irregular epiphyseal ossification with stippling of the main long bones were documented. Physeal overgrowth was massive in the left proximal humerus and femur. Furthermore, the hip joint appeared fused with an abundant mass of pathological calcific tissue extending from the femur to the ilium. Pathological epiphyses were characterized by anarchic cartilaginous proliferation with multiple ossification centres, while lamellar bone apposition and remodelling were normal. The observed bone changes were different from those in any previously reported syndrome, metabolic defect or bone dysplasia. However, they clearly indicated a defect of endochondral ossification with some resemblance to phenotypes observed in dysplasia epiphysealis hemimelica. (orig.)

MR diagnosis of temporomandibular joint. A study of joint effusion

International Nuclear Information System (INIS)

Kaneda, Takashi; Yamashiro, Mitsuaki; Ozawa, Kaoru; Suzuki, Hiromi; Okada, Hiroyuki; Yamamoto, Hirotsugu

1998-01-01

The purposes of this study were to evaluate the relationship between correlation of MR joint effusion of the temporomandibular joint and disk position, to evaluate the relationship between joint effusion and aging, and to assess the frequency of MR joint effusion of bilateral temporomandibular joints. The temporomandibular joints of 192 patients with clinical symptoms of temporomandibular joint disorders were imaged bilaterally using high field, surface-coil MR imaging. Oblique sagittal and coronal proton density-weighted and T2-weighted images were obtained. Imaging findings of joint effusion were correlated with disk position, aging, and bilateral temporomandibular joints. MR showed effusion in 4% of the joints with normal superior disk position, 36% of the joints with disk displacement with reduction, and 45% of the joints with disk displacement without reduction. There were significant differences in the incidence of joint effusion between normal disk position and anterior disk displacement with or without reduction. Younger patients less than 40 years were significant higher the incidence of joint effusion than those of older patients. A significant association was seen between joint effusion and aging. MR showed effusion in 17% of the unilateral temporomandibular joint, 24% of the bilateral temporomandibular joints. There was no significant difference between unilateral and bilateral case. These results indicated that joint effusion using MR imaging was associated with varied temporomandibular joint pathologic states. (author)

Hoechst and Wacker plan joint venture in PVC

International Nuclear Information System (INIS)

Young, I.

1992-01-01

Restructuring of Europe's petrochemical industry has taken a further step with the announcement that Hoechst (Frankfurt) and Wacker Chemie (Munich) are planning a joint venture in polyvinyl chloride (PVC). The venture would include production, R ampersand D, sales and marketing, plus both companies' PVC recycling activities. However, their vinyl chloride monomer (VCM) plants, and Hoechst's Kalle PVC film business, have been left out. Erich Schnitzler, head of Hoechst's PVC business unit, does not anticipate problems with the European Community's competition directorate. We are both among the middle-sized European PVC producers, and together we would have a 9%-10% market share. Our joint venture would not limit competition. Both partners are hoping for approval from Brussels in first-quarter 1993. Hoechst has 255,000 m.t./year of PVC capacity at Gendorfand Knapsack, while Wacker has 365,000 m.t./year at Burghausen and Cologne. All the units, except Wacker's Cologne plant, are back integrated to VCM. The joint venture would buy VCM from the two parent companies and on the merchant market

US initiative on joint implementation: An overview

Energy Technology Data Exchange (ETDEWEB)

Dixon, R.K. [Initiative on Joint Implementation, Washington, DC (United States)

1996-12-31

More than 150 countries are now Party to United Nations Framework Convention on Climate Change, which seeks as its ultimate objective, to stabilize atmospheric concentrations of greenhouse gases at a level that would prevent dangerous human interference with the global climate system. As a step towards that goal, all Parties are to take measures to mitigate greenhouse gas emissions and to promote cooperation in the development and diffusion of technologies and practices that control or reduce emissions and enhance sinks of greenhouse gases. In the U.S. view, efforts between countries or entities within them to reduce net greenhouse gas emissions undertaken cooperatively, termed joint implementation (JI), holds significant potential both for reducing the threat of global climate change and for promoting sustainable development. To develop and operationalize the JI concept, the U.S. launched its Initiative on Joint Implementation (IJI) in October, 1993, and designed a program to attract private sector resources and to encourage the diffusion of innovative technologies to mitigate greenhouse gas emissions. The goals of U.S. IJI complement the principles of Decision 5, First Conference of the FCCC Parties, establishing an Activities Implemented Jointly pilot phase.

A Model-Based Joint Identification of Differentially Expressed Genes and Phenotype-Associated Genes

Science.gov (United States)

Seo, Minseok; Shin, Su-kyung; Kwon, Eun-Young; Kim, Sung-Eun; Bae, Yun-Jung; Lee, Seungyeoun; Sung, Mi-Kyung; Choi, Myung-Sook; Park, Taesung

2016-01-01

Over the last decade, many analytical methods and tools have been developed for microarray data. The detection of differentially expressed genes (DEGs) among different treatment groups is often a primary purpose of microarray data analysis. In addition, association studies investigating the relationship between genes and a phenotype of interest such as survival time are also popular in microarray data analysis. Phenotype association analysis provides a list of phenotype-associated genes (PAGs). However, it is sometimes necessary to identify genes that are both DEGs and PAGs. We consider the joint identification of DEGs and PAGs in microarray data analyses. The first approach we used was a naïve approach that detects DEGs and PAGs separately and then identifies the genes in an intersection of the list of PAGs and DEGs. The second approach we considered was a hierarchical approach that detects DEGs first and then chooses PAGs from among the DEGs or vice versa. In this study, we propose a new model-based approach for the joint identification of DEGs and PAGs. Unlike the previous two-step approaches, the proposed method identifies genes simultaneously that are DEGs and PAGs. This method uses standard regression models but adopts different null hypothesis from ordinary regression models, which allows us to perform joint identification in one-step. The proposed model-based methods were evaluated using experimental data and simulation studies. The proposed methods were used to analyze a microarray experiment in which the main interest lies in detecting genes that are both DEGs and PAGs, where DEGs are identified between two diet groups and PAGs are associated with four phenotypes reflecting the expression of leptin, adiponectin, insulin-like growth factor 1, and insulin. Model-based approaches provided a larger number of genes, which are both DEGs and PAGs, than other methods. Simulation studies showed that they have more power than other methods. Through analysis of

A Model-Based Joint Identification of Differentially Expressed Genes and Phenotype-Associated Genes.

Directory of Open Access Journals (Sweden)

Samuel Sunghwan Cho

Full Text Available Over the last decade, many analytical methods and tools have been developed for microarray data. The detection of differentially expressed genes (DEGs among different treatment groups is often a primary purpose of microarray data analysis. In addition, association studies investigating the relationship between genes and a phenotype of interest such as survival time are also popular in microarray data analysis. Phenotype association analysis provides a list of phenotype-associated genes (PAGs. However, it is sometimes necessary to identify genes that are both DEGs and PAGs. We consider the joint identification of DEGs and PAGs in microarray data analyses. The first approach we used was a naïve approach that detects DEGs and PAGs separately and then identifies the genes in an intersection of the list of PAGs and DEGs. The second approach we considered was a hierarchical approach that detects DEGs first and then chooses PAGs from among the DEGs or vice versa. In this study, we propose a new model-based approach for the joint identification of DEGs and PAGs. Unlike the previous two-step approaches, the proposed method identifies genes simultaneously that are DEGs and PAGs. This method uses standard regression models but adopts different null hypothesis from ordinary regression models, which allows us to perform joint identification in one-step. The proposed model-based methods were evaluated using experimental data and simulation studies. The proposed methods were used to analyze a microarray experiment in which the main interest lies in detecting genes that are both DEGs and PAGs, where DEGs are identified between two diet groups and PAGs are associated with four phenotypes reflecting the expression of leptin, adiponectin, insulin-like growth factor 1, and insulin. Model-based approaches provided a larger number of genes, which are both DEGs and PAGs, than other methods. Simulation studies showed that they have more power than other methods

A review on model updating of joint structure for dynamic analysis purpose

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Zahari S.N.

2016-01-01

Full Text Available Structural joints provide connection between structural element (beam, plate etc. in order to construct a whole assembled structure. There are many types of structural joints such as bolted joint, riveted joints and welded joints. The joints structures significantly contribute to structural stiffness and dynamic behaviour of structures hence the main objectives of this paper are to review on method of model updating on joints structure and to discuss the guidelines to perform model updating for dynamic analysis purpose. This review paper firstly will outline some of the existing finite element modelling works of joints structure. Experimental modal analysis is the next step to obtain modal parameters (natural frequency & mode shape to validate and improve the discrepancy between results obtained from experimental and the simulation counterparts. Hence model updating will be carried out to minimize the differences between the two results. There are two methods of model updating; direct method and iterative method. Sensitivity analysis employed using SOL200 in NASTRAN by selecting the suitable updating parameters to avoid ill-conditioning problem. It is best to consider both geometrical and material properties in the updating procedure rather than choosing only a number of geometrical properties alone. Iterative method was chosen as the best model updating procedure because the physical meaning of updated parameters are guaranteed although this method required computational effort compare to direct method.

The diagnostic protocol for evaluation of periprosthetic joint infection

Directory of Open Access Journals (Sweden)

Alen Mlekuž

2015-06-01

Full Text Available Infection is becoming the most important as well as the most devastating mechanism of prosthetic joint failure. The incidence is increasing due to increased sensitivity of orthopedic surgeons for this diagnosis, better diagnostics, and  because the absolute number of operated patients is increasing and because more often very sick, debilitated, and immunocompromised patients are operated on. The trend shows the incidence to further increase in the years to come. The diagnosis may be very easy in case of high grade processes, but also extremely difficult in low grade infections. Misdiagnosing infection leads to repeat early failures and revisions that are distressing for patients as well as for surgeons. To avoid failures related to misdiagnosed prosthetic joint infections a step-wise algorithm of action is proposed and the diagnostic strength of the steps discussed. The key point is to select the potential candidates to define the possibility of an ongoing infection and then to select the tools to strengthen the suspicion. The further procedures base on the analysis of the pseudo-synovial fluid obtained by aspiration. The diagnostic conclusions form the basis for considered treatment decisions.

Joint importance sampling of low-order volumetric scattering

DEFF Research Database (Denmark)

Georgiev, Iliyan; Křivánek, Jaroslav; Hachisuka, Toshiya

2013-01-01

Central to all Monte Carlo-based rendering algorithms is the construction of light transport paths from the light sources to the eye. Existing rendering approaches sample path vertices incrementally when constructing these light transport paths. The resulting probability density is thus a product...... of the conditional densities of each local sampling step, constructed without explicit control over the form of the final joint distribution of the complete path. We analyze why current incremental construction schemes often lead to high variance in the presence of participating media, and reveal...... that such approaches are an unnecessary legacy inherited from traditional surface-based rendering algorithms. We devise joint importance sampling of path vertices in participating media to construct paths that explicitly account for the product of all scattering and geometry terms along a sequence of vertices instead...

Patellofemoral joint stress during running with alterations in foot strike pattern.

Science.gov (United States)

Vannatta, Charles Nathan; Kernozek, Thomas W

2015-05-01

This study aimed to quantify differences in patellofemoral joint stress that may occur when healthy runners alter their foot strike pattern from their habitual rearfoot strike to a forefoot strike to gain insight on the potential etiology and treatment methods of patellofemoral pain. Sixteen healthy female runners completed 20 running trials in a controlled laboratory setting under rearfoot strike and forefoot strike conditions. Kinetic and kinematic data were used to drive a static optimization technique to estimate individual muscle forces to input into a model of the patellofemoral joint to estimate joint stress during running. Peak patellofemoral joint stress and the stress-time integral over stance phase decreased by 27% and 12%, respectively, in the forefoot strike condition (P forefoot strike condition (P forefoot strike (P forefoot strike condition (P strike pattern to a forefoot strike results in consistent reductions in patellofemoral joint stress independent of changes in step length. Thus, implementation of forefoot strike training programs may be warranted in the treatment of runners with patellofemoral pain. However, it is suggested that the transition to a forefoot strike pattern should be completed in a graduated manner.

A Joint Less Ordinary: Intriguing Roles for Hedgehog Signalling in the Development of the Temporomandibular Synovial Joint

Directory of Open Access Journals (Sweden)

Malgorzata Kubiak

2016-08-01

Full Text Available This review highlights the essential role of Hedgehog (Hh signalling in the developmental steps of temporomandibular joint (TMJ formation. We review evidence for intra- and potentially inter-tissue Hh signaling as well as Glioma-Associated Oncogene Homolog (GLI dependent and independent functions. Morphogenesis and maturation of the TMJ’s individual components and the general landscape of Hh signalling is also covered. Comparison of the appendicular knee and axial TMJ also reveals interesting differences and similarities in their mechanisms of development, chondrogenesis and reliance on Hh signalling.

A Joint Less Ordinary: Intriguing Roles for Hedgehog Signalling in the Development of the Temporomandibular Synovial Joint

Science.gov (United States)

Kubiak, Malgorzata; Ditzel, Mark

2016-01-01

This review highlights the essential role of Hedgehog (Hh) signalling in the developmental steps of temporomandibular joint (TMJ) formation. We review evidence for intra- and potentially inter-tissue Hh signaling as well as Glioma-Associated Oncogene Homolog (GLI) dependent and independent functions. Morphogenesis and maturation of the TMJ’s individual components and the general landscape of Hh signalling is also covered. Comparison of the appendicular knee and axial TMJ also reveals interesting differences and similarities in their mechanisms of development, chondrogenesis and reliance on Hh signalling. PMID:29615589

Air stepping in response to optic flows that move Toward and Away from the neonate.

Science.gov (United States)

Barbu-Roth, Marianne; Anderson, David I; Desprès, Adeline; Streeter, Ryan J; Cabrol, Dominique; Trujillo, Michael; Campos, Joseph J; Provasi, Joëlle

2014-07-01

To shed further light on the perceptual regulation of newborn stepping, we compared neonatal air stepping in response to optic flows simulating forward or backward displacement with stepping forward on a surface. Twenty-two 3-day-olds performed four 60 s trials in which they stepped forward on a table (Tactile) or in the air in response to a pattern that moved toward (Toward) or away (Away) from them or was static (Static). Significantly more steps were taken in the Tactile and Toward conditions than the Static condition. The Away condition was intermediate to the other conditions. The knee joint activity across the entire trial was significantly greater in the Toward than the Away condition. Within-limb kinematics and between-limb coordination were very similar for steps taken in the air and on the table, particularly in the Toward and Tactile conditions. These findings highlight that visual and tactile stimulation can equally elicit neonatal stepping. © 2013 Wiley Periodicals, Inc.

Atomic-scale friction on stepped surfaces of ionic crystals.

Science.gov (United States)

Steiner, Pascal; Gnecco, Enrico; Krok, Franciszek; Budzioch, Janusz; Walczak, Lukasz; Konior, Jerzy; Szymonski, Marek; Meyer, Ernst

2011-05-06

We report on high-resolution friction force microscopy on a stepped NaCl(001) surface in ultrahigh vacuum. The measurements were performed on single cleavage step edges. When blunt tips are used, friction is found to increase while scanning both up and down a step edge. With atomically sharp tips, friction still increases upwards, but it decreases and even changes sign downwards. Our observations extend previous results obtained without resolving atomic features and are associated with the competition between the Schwöbel barrier and the asymmetric potential well accompanying the step edges.

Is early osteoarthritis associated with differences in joint congruence?

Science.gov (United States)

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.

Joint Rendering and Segmentation of Free-Viewpoint Video

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Ishii Masato

2010-01-01

Full Text Available Abstract This paper presents a method that jointly performs synthesis and object segmentation of free-viewpoint video using multiview video as the input. This method is designed to achieve robust segmentation from online video input without per-frame user interaction and precomputations. This method shares a calculation process between the synthesis and segmentation steps; the matching costs calculated through the synthesis step are adaptively fused with other cues depending on the reliability in the segmentation step. Since the segmentation is performed for arbitrary viewpoints directly, the extracted object can be superimposed onto another 3D scene with geometric consistency. We can observe that the object and new background move naturally along with the viewpoint change as if they existed together in the same space. In the experiments, our method can process online video input captured by a 25-camera array and show the result image at 4.55 fps.

SPAR-H Step-by-Step Guidance

Energy Technology Data Exchange (ETDEWEB)

W. J. Galyean; A. M. Whaley; D. L. Kelly; R. L. Boring

2011-05-01

This guide provides step-by-step guidance on the use of the SPAR-H method for quantifying Human Failure Events (HFEs). This guide is intended to be used with the worksheets provided in: 'The SPAR-H Human Reliability Analysis Method,' NUREG/CR-6883, dated August 2005. Each step in the process of producing a Human Error Probability (HEP) is discussed. These steps are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff. The discussions on dependence are extensive and include an appendix that describes insights obtained from the psychology literature.

SPAR-H Step-by-Step Guidance

International Nuclear Information System (INIS)

Galyean, W.J.; Whaley, A.M.; Kelly, D.L.; Boring, R.L.

2011-01-01

This guide provides step-by-step guidance on the use of the SPAR-H method for quantifying Human Failure Events (HFEs). This guide is intended to be used with the worksheets provided in: 'The SPAR-H Human Reliability Analysis Method,' NUREG/CR-6883, dated August 2005. Each step in the process of producing a Human Error Probability (HEP) is discussed. These steps are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff. The discussions on dependence are extensive and include an appendix that describes insights obtained from the psychology literature.

SPAR-H Step-by-Step Guidance

Energy Technology Data Exchange (ETDEWEB)

April M. Whaley; Dana L. Kelly; Ronald L. Boring; William J. Galyean

2012-06-01

Step-by-step guidance was developed recently at Idaho National Laboratory for the US Nuclear Regulatory Commission on the use of the Standardized Plant Analysis Risk-Human Reliability Analysis (SPAR-H) method for quantifying Human Failure Events (HFEs). This work was done to address SPAR-H user needs, specifically requests for additional guidance on the proper application of various aspects of the methodology. This paper overviews the steps of the SPAR-H analysis process and highlights some of the most important insights gained during the development of the step-by-step directions. This supplemental guidance for analysts is applicable when plant-specific information is available, and goes beyond the general guidance provided in existing SPAR-H documentation. The steps highlighted in this paper are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff.

Hybridization of electron states in a step quantum well in a magnetic field

International Nuclear Information System (INIS)

Barseghyan, M.G.; Kirakosyan, A.A.

2005-01-01

The quantum states and energy levels of an electrion in a rectangular step quantum well in a magnetic field parallel to the plane of two-dimentional electron gas are investigated. It is shown that the joint effect of the magnetic field and confining potential of the quantum well results in redical change of the electron spectrum. The dependence of the electron energy levels on the quantum well parameters, magnetic field induction and projection of the wave-vector along the magnetic field induction are calculated. Numerical calculations are carried out for a AlAs/GaAlAs/GaAs/AlAs step quantum well

Intermediate surface structure between step bunching and step flow in SrRuO3 thin film growth

Science.gov (United States)

Bertino, Giulia; Gura, Anna; Dawber, Matthew

We performed a systematic study of SrRuO3 thin films grown on TiO2 terminated SrTiO3 substrates using off-axis magnetron sputtering. We investigated the step bunching formation and the evolution of the SRO film morphology by varying the step size of the substrate, the growth temperature and the film thickness. The thin films were characterized using Atomic Force Microscopy and X-Ray Diffraction. We identified single and multiple step bunching and step flow growth regimes as a function of the growth parameters. Also, we clearly observe a stronger influence of the step size of the substrate on the evolution of the SRO film surface with respect to the other growth parameters. Remarkably, we observe the formation of a smooth, regular and uniform ``fish skin'' structure at the transition between one regime and another. We believe that the fish skin structure results from the merging of 2D flat islands predicted by previous models. The direct observation of this transition structure allows us to better understand how and when step bunching develops in the growth of SrRuO3 thin films.

Imaging osteoarthritis in the knee joints using x-ray guided diffuse optical tomography

Science.gov (United States)

Zhang, Qizhi; Yuan, Zhen; Sobel, Eric S.; Jiang, Huabei

2010-02-01

In our previous studies, near-infrared (NIR) diffuse optical tomography (DOT) had been successfully applied to imaging osteoarthritis (OA) in the finger joints where significant difference in optical properties of the joint tissues was evident between healthy and OA finger joints. Here we report for the first time that large joints such as the knee can also be optically imaged especially when DOT is combined with x-ray tomosynthesis where the 3D image of the bones from x-ray is incorporated into the DOT reconstruction as spatial a priori structural information. This study demonstrates that NIR light can image large joints such as the knee in addition to finger joints, which will drastically broaden the clinical utility of our x-ray guided DOT technique for OA diagnosis.

Experimental and theoretical investigation of column - flat slab joint ductility

International Nuclear Information System (INIS)

Iskhakov, I.; Ribakov, Y.; Shah, A.

2009-01-01

Most modern seismic codes use ductility as one of the basic design parameters. Actually, ductility defines the ability of a structure or its elements to absorb energy by plastic deformations. Until the end of the previous century ductility was defined qualitatively. Most research works related to ductility are focused on structural elements' sections. This study was aimed at complex experimental and theoretical investigation of flat slab-column joints ductility. It is one of the first attempts to obtain quantitative values of joint's ductility for the case of high strength concrete columns and normal strength concrete slabs. It was shown that the flat slab-column joint is a three-dimension (3D) element and its ductility in horizontal and vertical directions are different. This is the main difference between ductility of elements and joint ductility. In case of flat slab-column joints, essential contribution to joint's ductility can be obtained due to the slab's confining effect. Based on experimental data, the authors demonstrate that flat slab-column joint's ductility depends on the joint's confining effect in two horizontal and vertical directions. Furthermore, the influence of slab load intensity and slab reinforcement ratio on the joint's ductility is performed in this study. It is also demonstrated that the effect of the ratio between the slab thickness and the column's section dimension on the ductility parameter is significant. Equations for obtaining a quantitative value of a flat slab-column joint's ductility parameter were developed.

Diffusion coefficients for multi-step persistent random walks on lattices

International Nuclear Information System (INIS)

Gilbert, Thomas; Sanders, David P

2010-01-01

We calculate the diffusion coefficients of persistent random walks on lattices, where the direction of a walker at a given step depends on the memory of a certain number of previous steps. In particular, we describe a simple method which enables us to obtain explicit expressions for the diffusion coefficients of walks with a two-step memory on different classes of one-, two- and higher dimensional lattices.

Intra-articular pressures and joint mechanics: should we pay attention to effusion in knee osteoarthritis?

Science.gov (United States)

Rutherford, Derek James

2014-09-01

What factors play a role to ensure a knee joint does what it should given the demands of moving through the physical environment? This paper aims to probe the hypothesis that intra-articular joint pressures, once a topic of interest, have been left aside in contemporary frameworks in which we now view knee joint function. The focus on ligamentous deficiencies and the chondrocentric view of osteoarthritis, while important, have left little attention to the consideration of other factors that can impair joint function across the lifespan. Dynamic knee stability is required during every step we take. While there is much known about the role that passive structures and muscular activation play in maintaining a healthy knee joint, this framework does not account for the role that intra-articular joint pressures may have in providing joint stability during motion and how these factors interact. Joint injuries invariably result in some form of intra-articular fluid accumulation. Ultimately, it may be how the knee mechanically responds to this fluid, of which pressure plays a significant role that provides the mechanisms for continued function. Do joint pressures provide an important foundation for maintaining knee function? This hypothesis is unique and argues that we are missing an important piece of the puzzle when attempting to understand implications that joint injury and disease have for joint function. Copyright © 2014 Elsevier Ltd. All rights reserved.

A Statistical-Probabilistic Pattern for Determination of Tunnel Advance Step by Quantitative Risk Analysis

Directory of Open Access Journals (Sweden)

sasan ghorbani

2017-12-01

distributions of normal, lognormal, and gamma, under the scenario with poor section, effect of normal stiffness of joints on excavation advance step was larger than the effect of other parameters. Accordingly, with increasing RMR quality, normal stiffness of joints was seen to decrease, so that deformability modulus became more significant.

Ankle Joint Intrinsic Dynamics is More Complex than a Mass-Spring-Damper Model.

Science.gov (United States)

Sobhani Tehrani, Ehsan; Jalaleddini, Kian; Kearney, Robert E

2017-09-01

This paper describes a new small signal parametric model of ankle joint intrinsic mechanics in normal subjects. We found that intrinsic ankle mechanics is a third-order system and the second-order mass-spring-damper model, referred to as IBK, used by many researchers in the literature cannot adequately represent ankle dynamics at all frequencies in a number of important tasks. This was demonstrated using experimental data from five healthy subjects with no voluntary muscle contraction and at seven ankle positions covering the range of motion. We showed that the difference between the new third-order model and the conventional IBK model increased from dorsi to plantarflexed position. The new model was obtained using a multi-step identification procedure applied to experimental input/output data of the ankle joint. The procedure first identifies a non-parametric model of intrinsic joint stiffness where ankle position is the input and torque is the output. Then, in several steps, the model is converted into a continuous-time transfer function of ankle compliance, which is the inverse of stiffness. Finally, we showed that the third-order model is indeed structurally consistent with agonist-antagonist musculoskeletal structure of human ankle, which is not the case for the IBK model.

Detection of periprosthetic joint infections in presumed aseptic patients

DEFF Research Database (Denmark)

Xu, Yijuan; Lorenzen, Jan; Thomsen, Trine Rolighed

2016-01-01

Title: Detection of periprosthetic joint infections in presumed aseptic patients Yijuan Xu1, Jan Lorenzen1, Trine Rolighed Thomsen1,2, Kathrin Kluba3, Kathrin Chamaon3, Christoph Lohmann3 1. Danish Technological Institute, Aarhus, Denmark 2. Center for Microbial Communities, Department of Biotech......Title: Detection of periprosthetic joint infections in presumed aseptic patients Yijuan Xu1, Jan Lorenzen1, Trine Rolighed Thomsen1,2, Kathrin Kluba3, Kathrin Chamaon3, Christoph Lohmann3 1. Danish Technological Institute, Aarhus, Denmark 2. Center for Microbial Communities, Department...... of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Denmark 3. Department of Orthopaedics, Otto-von-Guericke University of Magdeburg, Germany Aim: ”The HypOrth project (New approaches in the development of Hypoallergenic implant material in Orthopaedics: Steps to personalised medicine......) aims to investigate adverse immune reactions to implant materials. For this project, it is of utmost importance to exclude patients with periprosthetic joint infections (PJIs). The aim of this study was to rule out PJIs in included patients using prolonged culture and next generation sequencing (NGS...

Joint attention, social cognition and recognition memory in adults

Directory of Open Access Journals (Sweden)

Kwanguk eKim

2012-06-01

Full Text Available The early emerging capacity for Joint Attention, or socially coordinated visual attention, is thought to be integral to the development of social-cognition in childhood. Recent studies have also begun to suggest that joint attention affects adult cognition as well, but methodological limitations hamper research on this topic. To address this issue we developed a novel virtual reality (VR paradigm that integrates eye-tracking and virtual avatar technology to measure two types of joint attention in adults, Initiating Joint Attention (IJA and Responding to Joint Attention (RJA. Distinguishing these types of joint attention in research is important because they are thought to reflect unique, as well as common constellations of processes involved in human social-cognition and social learning. We tested the validity of the differentiation of IJA and RJA in our paradigm in two studies of picture recognition memory in undergraduate students. Study 1 indicated that young adults correctly identified more pictures they had previously viewed in an IJA condition (67% than in a RJA (58% condition, η2 = .57. Study 2 controlled for IJA and RJA stimulus viewing time differences, and replicated the findings of Study 1. The implications of these results for the validity of the paradigm and research on the affects of joint attention on adult social-cognition are discussed.

Degenerative joint disease on MRI and physical activity: a clinical study of the knee joint in 320 patients

International Nuclear Information System (INIS)

Bachmann, G.F.; Rauber, K.; Damian, M.S.; Rau, W.S.; Basad, E.

1999-01-01

We examined 320 patients with MRI and arthroscopy after an acute trauma to evaluate MRI in diagnosis of degenerative joint disease of the knee in relation to sports activity and clinical data. Lesions of cartilage and menisci on MRI were registered by two radiologists in consensus without knowledge of arthroscopy. Arthroscopy demonstrated grade-1 to grade-4 lesions of cartilage on 729 of 1920 joint surfaces of 320 knees, and MRI diagnosed 14 % of grade-1, 32 % of grade-2, 94 % of grade-3, and 100 % of grade-4 lesions. Arthroscopy explored 1280 meniscal areas and showed degenerations in 10 %, tears in 11.4 %, and complex lesions in 9.2 %. Magnetic resonance imaging was in agreement with arthroscopy in 81 % showing more degenerations but less tears of menisci than arthroscopy. Using a global system for grading the total damage of the knee joint into none, mild, moderate, or severe changes, agreement between arthroscopy and MRI was found in 82 %. Magnetic resonance imaging and arthroscopy showed coherently that degree of degenerative joint changes was significantly correlated to patient age or previous knee trauma. Patients over 40 years had moderate to severe changes on MRI in 45 % and patients under 30 years in only 22 %. Knee joints with a history of trauma without complete structural or functional reconstitution showed marked changes on MRI in 57 %, whereas stable joints without such alterations had degenerative changes in only 26 %. There was no correlation of degenerative disease to gender, weight, type, frequency, and intensity of sports activity. Therefore, MRI is an effective non-invasive imaging method for exact localization and quantification of chronic joint changes of cartilage and menisci that recommends MRI for monitoring in sports medicine. (orig.) (orig.)

Influence of end-joint methods on magnetization loss in striated helical conductors

International Nuclear Information System (INIS)

Kim, Woo Seok; Kim, Yung Il; Choi, Kyeong Dal; Lee, Ji Kwang

2013-01-01

To reduce the magnetization loss of a coated conductor, the striation and the transposition have to be accomplished for magnetic decoupling. The loss reduction effect in incomplete as well as complete striated YBCO CCs was reported in previous research. At the case of the incomplete striated sample, the end region of the sample is non-striated. So, it is not jointed with each other. In power applications, the joint is needed because current leads must be connected with HTS coils. In this research, the influence of end-joint methods with copper and superconducting joint on magnetization loss in striated YBCO CC and spiral winding samples are presented and compared with non-striated measured result.

On joint spectra of families of unbounded operators

International Nuclear Information System (INIS)

Mirotin, A R

2015-01-01

We consider several types of joint spectra of a finite set of commuting closed operators in a Banach space. We establish new relations between these spectra (it was previously known only that the Taylor spectrum is contained in the commutant spectrum) and prove spectral mapping theorems in the case of generators of semigroups. Some of these theorems generalize previous results of the author. The results obtained are applied to stability issues for multi-parameter semigroups

Determination of Parachute Joint Factors using Seam and Joint Testing

Science.gov (United States)

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.

Temporomandibular joint space in children without joint disease

International Nuclear Information System (INIS)

Larheim, T.A.

1981-01-01

Bilateral assessment of the temporomandibular joint space in children without joint disease is reported. Twenty-eight children were examined with conventional radiography and 23 with tomography. High prevalence of asymmetric joint spaces with both techniques indicated that great care should be taken when using narrowing or widening of the joint space as a diagnostic criterion in children with juvenile rheumatoid arthritis. Other signs, such as restricted translation of the mandibular head, and clinical symptoms should be evaluated. (Auth.)

Techniques of Force and Pressure Measurement in the Small Joints of the Wrist.

Science.gov (United States)

Schreck, Michael J; Kelly, Meghan; Canham, Colin D; Elfar, John C

2018-01-01

The alteration of forces across joints can result in instability and subsequent disability. Previous methods of force measurements such as pressure-sensitive films, load cells, and pressure-sensing transducers have been utilized to estimate biomechanical forces across joints and more recent studies have utilized a nondestructive method that allows for assessment of joint forces under ligamentous restraints. A comprehensive review of the literature was performed to explore the numerous biomechanical methods utilized to estimate intra-articular forces. Methods of biomechanical force measurements in joints are reviewed. Methods such as pressure-sensitive films, load cells, and pressure-sensing transducers require significant intra-articular disruption and thus may result in inaccurate measurements, especially in small joints such as those within the wrist and hand. Non-destructive methods of joint force measurements either utilizing distraction-based joint reaction force methods or finite element analysis may offer a more accurate assessment; however, given their recent inception, further studies are needed to improve and validate their use.

Biomechanical and neuromuscular adaptations during the landing phase of a stepping-down task in patients with early or established knee osteoarthritis.

Science.gov (United States)

Sanchez-Ramirez, Diana C; Malfait, Bart; Baert, Isabel; van der Leeden, Marike; van Dieën, Jaap; Lems, Willem F; Dekker, Joost; Luyten, Frank P; Verschueren, Sabine

2016-06-01

To compare the knee joint kinematics, kinetics and EMG activity patterns during a stepping-down task in patients with knee osteoarthritis (OA) with control subjects. 33 women with knee OA (early OA, n=14; established OA n=19) and 14 female control subjects performed a stepping-down task from a 20cm step. Knee joint kinematics, kinetics and EMG activity were recorded on the stepping-down leg during the loading phase. During the stepping-down task patients with established knee OA showed greater normalized medial hamstrings activity (p=0.034) and greater vastus lateralis-medial hamstrings co-contraction (p=0.012) than controls. Greater vastus medialis-medial hamstrings co-contraction was found in patients with established OA compared to control subjects (p=0.040) and to patients with early OA (p=0.023). Self-reported knee instability was reported in 7% and 32% of the patients with early and established OA, respectively. The greater EMG co-activity found in established OA might suggest a less efficient use of knee muscles or an attempt to compensate for greater knee laxity usually present in patients with established OA. In the early stage of the disease, the biomechanical and neuromuscular control of stepping-down is not altered compared to healthy controls. Copyright © 2016 Elsevier B.V. All rights reserved.

Product analysis illuminates the final steps of IES deletion in Tetrahymena thermophila.

Science.gov (United States)

Saveliev, S V; Cox, M M

2001-06-15

DNA sequences (IES elements) eliminated from the developing macronucleus in the ciliate Tetrahymena thermophila are released as linear fragments, which have now been detected and isolated. A PCR-mediated examination of fragment end structures reveals three types of strand scission events, reflecting three steps in the deletion process. New evidence is provided for two steps proposed previously: an initiating double-stranded cleavage, and strand transfer to create a branched deletion intermediate. The fragment ends provide evidence for a previously uncharacterized third step: the branched DNA strand is cleaved at one of several defined sites located within 15-16 nucleotides of the IES boundary, liberating the deleted DNA in a linear form.

Ligamentous and capsular restraints to experimental posterior elbow joint dislocation

DEFF Research Database (Denmark)

Deutch, S.R.; Olsen, B.S.; Jensen, S.L.

2003-01-01

the anterior capsule and the lateral collateral ligament complex (LCLC), whereas in the flexed elbow the anterior capsule did not have a stabilizing effect. In flexed joint positions, the LCLC seems to be the only immediate stabilizer against PEFR, and thereby against posterolateral instability and possibly...... against posterior dislocation. The medial collateral ligament did not have any immediate stabilizing effect, but it prevented the final step of the posterior dislocation....

Step out - Step in Sequencing Games

NARCIS (Netherlands)

Musegaas, M.; Borm, P.E.M.; Quant, M.

2014-01-01

In this paper a new class of relaxed sequencing games is introduced: the class of Step out - Step in sequencing games. In this relaxation any player within a coalition is allowed to step out from his position in the processing order and to step in at any position later in the processing order.

Analysis on burnup step effect for evaluating reactor criticality and fuel breeding ratio

International Nuclear Information System (INIS)

Saputra, Geby; Purnama, Aditya Rizki; Permana, Sidik; Suzuki, Mitsutoshi

2014-01-01

Criticality condition of the reactors is one of the important factors for evaluating reactor operation and nuclear fuel breeding ratio is another factor to show nuclear fuel sustainability. This study analyzes the effect of burnup steps and cycle operation step for evaluating the criticality condition of the reactor as well as the performance of nuclear fuel breeding or breeding ratio (BR). Burnup step is performed based on a day step analysis which is varied from 10 days up to 800 days and for cycle operation from 1 cycle up to 8 cycles reactor operations. In addition, calculation efficiency based on the variation of computer processors to run the analysis in term of time (time efficiency in the calculation) have been also investigated. Optimization method for reactor design analysis which is used a large fast breeder reactor type as a reference case was performed by adopting an established reactor design code of JOINT-FR. The results show a criticality condition becomes higher for smaller burnup step (day) and for breeding ratio becomes less for smaller burnup step (day). Some nuclides contribute to make better criticality when smaller burnup step due to individul nuclide half-live. Calculation time for different burnup step shows a correlation with the time consuming requirement for more details step calculation, although the consuming time is not directly equivalent with the how many time the burnup time step is divided

Enhancement of C/C-LAS joint using aligned carbon nanotubes prepared by injection chemical vapor deposition

Energy Technology Data Exchange (ETDEWEB)

Zhao, Feng-Ling; Fu, Qian-Gang, E-mail: fuqiangang@nwpu.edu.cn; Feng, Lei; Shen, Qing-Liang

2016-01-05

Carbon nanotubes (CNTs) enhanced carbon/carbon-lithium aluminum silicate (C/C-LAS) joint was prepared by a three-step technique of pack cementation, injection chemical vapor deposition (ICVD) and hot-pressing. A layer of aligned CNTs was grown on the surface of SiC coated C/C composites by ICVD method, and the joint was obtained by hot-pressing with magnesium aluminum silicate (MAS) as the interlayer. SEM observation reveals that the introduced CNTs result in the formation of a dense and crack-free CNT/MAS nanocomposite interface between SiC and MAS. Compared with the joints without CNTs, the average shear strength of the joints reinforced by CNTs was improved by 48% accompanied by an obvious change in failure mode from brittle fracture without CNTs to plastic fracture with CNTs. The pulling-out and bridging of CNTs on the fracture surfaces had a positive effect on the strength enhancement of the C/C-LAS joint.

Joint Replacement (Finger and Wrist Joints)

Science.gov (United States)

... All Topics A-Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is a Hand Surgeon? What is a Hand Therapist? Media Find a Hand Surgeon Home Anatomy Joint Replacement Email to a friend * required fields ...

Joint Operation Planning

National Research Council Canada - National Science Library

2006-01-01

.... It sets forth joint doctrine to govern the joint operation planning activities and performance of the Armed Forces of the United States in joint operations, and provides the joint doctrinal basis...

Step out-step in sequencing games

NARCIS (Netherlands)

Musegaas, Marieke; Borm, Peter; Quant, Marieke

2015-01-01

In this paper a new class of relaxed sequencing games is introduced: the class of Step out–Step in sequencing games. In this relaxation any player within a coalition is allowed to step out from his position in the processing order and to step in at any position later in the processing order. First,

Jointness for the Rest of Us: Reforming Joint Professional Development

Science.gov (United States)

2016-06-10

transferred to the Joint Staff. 13 DOD’s instinct to “overly centralize planning, organization, and management.”20 The authors contend that this...2. 3 John F. Schank and others, Who is Joint? Reevaluating the Joint Duty Assignment List : A Study Prepared for the Joint Staff, by the RAND...and code those billets as such. Once identified, DOD must expand the Joint Duty Assignment List (JDAL) to include billets that offer enlisted personnel

Management of organizational changes in the joint stock company

OpenAIRE

Vladimír Štípek

2005-01-01

The aim of the article is analysis of effects of organizational changes of Jihočeská energetika, joint stock company. This company accomplished the necessary steps to transform into new organization - the E.ON Group in Czech Republic. Liberalization of electricity market in Czech Republic saw the possibility for end - customers. The large boom in the development of organization came with the change of the of the owners. This company uses traditional line and staff organization chart, direct, ...

In vitro V(D)J recombination: Signal joint formation

OpenAIRE

Cortes, Patricia; Weis-Garcia, Frances; Misulovin, Ziva; Nussenzweig, Andre; Lai, Jiann-Shiun; Li, Gloria; Nussenzweig, Michel C.; Baltimore, David

1996-01-01

The first step of V(D)J recombination, specific cleavage at the recombination signal sequence (RSS), can be carried out by the recombination activating proteins RAG1 and RAG2. In vivo, the cleaved coding and signal ends must be rejoined to generate functional antigen receptors and maintain chromosomal integrity. We have investigated signal joint formation using deletion and inversion substrates in a cell free system. RAG1 and RAG2 alone or in combination were unabl...

Stepped-to-dart Leaders in Cloud-to-ground Lightning

Science.gov (United States)

Stolzenburg, M.; Marshall, T. C.; Karunarathne, S.; Karunarathna, N.; Warner, T.; Orville, R. E.

2013-12-01

Using time-correlated high-speed video (50,000 frames per second) and fast electric field change (5 MegaSamples per second) data for lightning flashes in East-central Florida, we describe an apparently rare type of subsequent leader: a stepped leader that finds and follows a previously used channel. The observed 'stepped-to-dart leaders' occur in three natural negative ground flashes. Stepped-to-dart leader connection altitudes are 3.3, 1.6 and 0.7 km above ground in the three cases. Prior to the stepped-to-dart connection, the advancing leaders have properties typical of stepped leaders. After the connection, the behavior changes almost immediately (within 40-60 us) to dart or dart-stepped leader, with larger amplitude E-change pulses and faster average propagation speeds. In this presentation, we will also describe the upward luminosity after the connection in the prior return stroke channel and in the stepped leader path, along with properties of the return strokes and other leaders in the three flashes.

Rapidly growing non-tuberculous mycobacteria infection of prosthetic knee joints: A report of two cases.

Science.gov (United States)

Kim, Manyoung; Ha, Chul-Won; Jang, Jae Won; Park, Yong-Beom

2017-08-01

Non-tuberculous mycobacteria (NTM) cause prosthetic knee joint infections in rare cases. Infections with rapidly growing non-tuberculous mycobacteria (RGNTM) are difficult to treat due to their aggressive clinical behavior and resistance to antibiotics. Infections of a prosthetic knee joint by RGNTM have rarely been reported. A standard of treatment has not yet been established because of the rarity of the condition. In previous reports, diagnoses of RGNTM infections in prosthetic knee joints took a long time to reach because the condition was not suspected, due to its rarity. In addition, it is difficult to identify RGNTM in the lab because special identification tests are needed. In previous reports, after treatment for RGNTM prosthetic infections, knee prostheses could not be re-implanted in all cases but one, resulting in arthrodesis or resection arthroplasty; this was most likely due to the aggressiveness of these organisms. In the present report, two cases of prosthetic knee joint infection caused by RGNTM (Mycobacterium abscessus) are described that were successfully treated, and in which prosthetic joints were finally reimplanted in two-stage revision surgery. Copyright © 2017 Elsevier B.V. All rights reserved.

Periprosthetic joint infection: are patients with multiple prosthetic joints at risk?

Science.gov (United States)

Jafari, S Mehdi; Casper, David S; Restrepo, Camilo; Zmistowski, Benjamin; Parvizi, Javad; Sharkey, Peter F

2012-06-01

Patients who present with a periprosthetic joint infection in a single joint may have multiple prosthetic joints. The risk of these patients developing a subsequent infection in another prosthetic joint is unknown. Our purposes were (1) to identify the risk of developing a subsequent infection in another prosthetic joint and (2) to describe the time span and organism profile to the second prosthetic infection. We retrospectively identified 55 patients with periprosthetic joint infection who had another prosthetic joint in place at the time of presentation. Of the 55 patients, 11 (20%) developed a periprosthetic joint infection in a second joint. The type of organism was the same as the first infection in 4 (36%) of 11 patients. The time to developing a second infection averaged 2.0 years (range, 0-6.9 years). Copyright © 2012 Elsevier Inc. All rights reserved.

Friction stir welding of T joints of dissimilar aluminum alloy: A review

Science.gov (United States)

Thakare, Shrikant B.; Kalyankar, Vivek D.

2018-04-01

Aluminum alloys are preferred in the mechanical design due to their advantages like high strength, good corrosion resistance, low density and good weldability. In various industrial applications T joints configuration of aluminum alloys are used. In different fields, T joints having skin (horizontal sheet) strengthen by stringers (vertical sheets) were used to increase the strength of structure without increasing the weight. T joints are usually carried out by fusion welding which has limitations in joining of aluminum alloy due to significant distortion and metallurgical defects. Some aluminum alloys are even non weldable by fusion welding. The friction stir welding (FSW) has an excellent replacement of conventional fusion welding for T joints. In this article, FSW of T joints is reviewed by considering aluminum alloy and various joint geometries for defect analysis. The previous experiments carried out on T joints shows the factors such as tool geometry, fixturing device and joint configurations plays significant role in defect free joints. It is essential to investigate the material flow during FSW to know joining mechanism and the formation of joint. In this study the defect occurred in the FSW are studied for various joint configurations and parameters. Also the effect of the parameters and defects occurs on the tensile strength are studied. It is concluded that the T-joints of different joint configurations can be pretended successfully. Comparing to base metal some loss in tensile strength was observed in the weldments as well as overall reduction of the hardness in the thermos mechanically affected zone also observed.

Stepping motors a guide to theory and practice

CERN Document Server

Acarnely, Paul

2002-01-01

This book provides an introductory text which will enable the reader to both appreciate the essential characteristics of stepping motor systems and understand how these characteristics are being exploited in the continuing development of new motors, drives and controllers. A basic theoretical approach relating to the more significant aspects of performance is presented, although it is assumed throughout that the reader has no previous experience of electrical machines and is primarily interested in the applications of stepping motors.

Coracoclavicular joint

Energy Technology Data Exchange (ETDEWEB)

Kim, Kun Sang; Park, Chan Il; Ahn, Jae Doo; Lim, Chong Won [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1970-10-15

The coracoclvicular joint, a rear abnormality which may be the cause of pain in the shoulder and limitation of motion of the shoulder joint, is discussed. A case of coracoclvicular joint with shoulder pain was observed in 65 yrs old Korean male.

Behavior of an epoxy-polysulfide adhesive in wood joints exposed to moisture content changes

Science.gov (United States)

Gordon P. Krueger

1965-01-01

The mechanical behavior of a flexible epoxy-resin adhesive system was observed in joints of plywood to lumber. The joints were subjected to internal swelling stresses caused by an increase in moisture content. Previous experimental work at the U.S. Forest Products Laboratory has shown that this adhesive system acts as a strain-absorbing cushion and thus has a...

Joint Convention on the safety of spent fuel management and on the safety of radioactive waste management. Third review meeting. Questions asked to France and answers

International Nuclear Information System (INIS)

2009-01-01

The Joint Convention on the Safety of Spent Fuel Management and the Safety of Radioactive Waste Management, referred to as the 'Joint Convention', is the result of international discussions that followed the adoption of the Convention on Nuclear Safety, in 1994. France signed the Joint Convention at the General Conference of the International Atomic Energy Agency (IAEA) held on 29 September 1997, the very first day the Joint Convention was opened for signature. She approved it on 22 February 2000 and filed the corresponding instruments with the IAEA on 27 April 2000. The Joint Convention entered into force on 18 June 2001. For many years, France has been taking an active part in the pursuit of international actions to reinforce nuclear safety and considers the Joint Convention to be a key step in that direction. The fields covered by the Joint Convention have long been part of the French approach to nuclear safety. For his third report, France presented a document reflecting the viewpoints of the various stakeholders (regulatory authorities and operators). Thus, for each of the chapters in which the regulatory authority is not the only party to express its point of view, a three-stage structure was adopted: first of all a description by the regulatory authority of the regulations, followed by a presentation by the operators of the steps taken to meet the regulations and finally, an analysis by the regulatory authority of the steps taken by the operators. This third report was distributed in October 2008 to all Contracting Parties who asked 213 questions on the French report. France answered each of them in the present document

Temporomandibular joint

International Nuclear Information System (INIS)

Westesson, P.L.; Hatala, M.; Tallents, R.H.; Katzberg, R.W.; Musgrave, M.; Levitt, S.

1990-01-01

This paper determines the frequency of MR signs of abnormal temporomandibular joints (TMJs) in asymptomatic volunteers. Forty-two volunteers with 84 clinically normal TMJs were imaged in the sagittal and coronal planes with surface coil MR imaging. Sagittal closed and open and coronal closed views were obtained bilaterally in all volunteers. The images were classified as normal (superior disk position) or abnormal (disk displacement of degenerative joint disease). Eighteen joints in 11 volunteers were abnormal; 12 had disk displacement with reduction and six had disk displacement without reduction, with associated degenerative joint disease in three of the six. Asymptomatic internal derangement and degenerative joint disease occur in about one-fourth of asymptomatic volunteers

Coordination of push-off and collision determine the mechanical work of step-to-step transitions when isolated from human walking.

Science.gov (United States)

Soo, Caroline H; Donelan, J Maxwell

2012-02-01

In human walking, each transition to a new stance limb requires redirection of the center of mass (COM) velocity from one inverted pendulum arc to the next. While this can be accomplished with either negative collision work by the leading limb, positive push-off work by the trailing limb, or some combination of the two, physics-based models of step-to-step transitions predict that total positive work is minimized when the push-off and collision work are equal in magnitude. Here, we tested the importance of the coordination of push-off and collision work in determining transition work using ankle and knee joint braces to limit the ability of a leg to perform positive work on the body. To isolate transitions from other contributors to walking mechanics, participants were instructed to rock back and forth from one leg to the other, restricting motion to the sagittal plane and eliminating the need to swing the legs. We found that reduced push-off work increased the collision work required to complete the redirection of the COM velocity during each transition. A greater amount of total mechanical work was required when rocking departed from the predicted optimal coordination of step-to-step transitions, in which push-off and collision work are equal in magnitude. Our finding that transition work increases if one or both legs do not push-off with the optimal coordination may help explain the elevated metabolic cost of pathological gait irrespective of etiology. Copyright © 2011 Elsevier B.V. All rights reserved.

Sweden's fourth national report under the Joint Convention on the safety of spent fuel management and the safety of radioactive waste management. Swedish implementation of the obligations of the Joint Convention

International Nuclear Information System (INIS)

2011-01-01

Sweden signed Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management (Joint Convention) September 29, 1997. Sweden ratified the Joint Convention about two years later and is a Contracting Party to the Joint Convention since July 29, 1999. The Joint Convention entered into force on June 18, 2001. Each member nation having ratified the Joint Convention (Contracting Party) is obligated to prepare a National Report covering the scope of the Joint Convention and subject it to review by other Contracting Parties at Review Meetings held in Vienna, Austria. Sweden participated in the First Review Meeting in November 2003, the Second Review Meeting in May 2006 and the Third Review Meeting in May 2009. This report is the fourth Swedish National Report under the Joint Convention. This report satisfies the requirements of the Joint Convention for reporting on the status of safety at spent fuel and radioactive waste management facilities within Sweden. It constitutes an updated document with basically the same structure as the previous national reports under the terms of the Joint Convention and reflects developments in Sweden through December 2010. It will be subject to review at the Fourth Review Meeting of the Contracting Parties in Vienna, Austria, in May 2012

Biochemical and biomechanical characterisation of equine cervical facet joint cartilage.

Science.gov (United States)

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

2018-04-15

The equine cervical facet joint is a site of significant pathology. Located bilaterally on the dorsal spine, these diarthrodial joints work in conjunction with the intervertebral disc to facilitate appropriate spinal motion. Despite the high prevalence of pathology in this joint, the facet joint is understudied and thus lacking in viable treatment options. The goal of this study was to characterise equine facet joint cartilage and provide a comprehensive database describing the morphological, histological, biochemical and biomechanical properties of this tissue. Descriptive cadaver studies. A total of 132 facet joint surfaces were harvested from the cervical spines of six skeletally mature horses (11 surfaces per animal) for compiling biomechanical and biochemical properties of hyaline cartilage of the equine cervical facet joints. Gross morphometric measurements and histological staining were performed on facet joint cartilage. Creep indentation and uniaxial strain-to-failure testing were used to determine the biomechanical compressive and tensile properties. Biochemical assays included quantification of total collagen, sulfated glycosaminoglycan and DNA content. The facet joint surfaces were ovoid in shape with a flat articular surface. Histological analyses highlighted structures akin to articular cartilage of other synovial joints. In general, biomechanical and biochemical properties did not differ significantly between the inferior and superior joint surfaces as well as among spinal levels. Interestingly, compressive and tensile properties of cervical facet articular cartilage were lower than those of articular cartilage from other previously characterised equine joints. Removal of the superficial zone reduced the tissue's tensile strength, suggesting that this zone is important for the tensile integrity of the tissue. Facet surfaces were sampled at a single, central location and do not capture the potential topographic variation in cartilage properties. This

The challenge of interdisciplinarity. First steps towards a joint working approach. The ENTRIA project

Energy Technology Data Exchange (ETDEWEB)

Roehlig, Klaus-Juergen [TU Clausthal, Clausthal-Zellerfeld (Germany). IELF; Hocke, Peter [Karlsruhe Institute of Technology, Karlsruhe (Germany). ITAS; Smeddinck, Ulrich [TU Braunschweig (Germany). IRW; Walther, Clemens [Hannover Univ. (Germany). IRS

2015-07-01

ENTRIA (''Disposal Options for Radioactive Residues: Interdisciplinary Analyses and Development of Evaluation Principles'') is a joint research project funded by the German Federal Ministry of Education and Research (BMBF) and carried out by 12 departments from German universities and major research institutions and one partner from Switzerland. The scientists participating in ENTRIA represent natural sciences, civil engineering, philosophy, law, social and political sciences, and technology assessment. Recognizing that all these disciplines need to interact when radioactive waste management is concerned, the project aims at investigating and developing evaluation principles for three options to manage especially high-level radioactive waste: Deep disposal without retrievability provisions, emplacement in deep formations with monitoring and retrievability, and prolonged surface storage. While ENTRIA performs both disciplinary and interdisciplinary research, the paper focusses on the latter.

The challenge of interdisciplinarity. First steps towards a joint working approach. The ENTRIA project

International Nuclear Information System (INIS)

Roehlig, Klaus-Juergen; Hocke, Peter; Smeddinck, Ulrich; Walther, Clemens

2015-01-01

ENTRIA (''Disposal Options for Radioactive Residues: Interdisciplinary Analyses and Development of Evaluation Principles'') is a joint research project funded by the German Federal Ministry of Education and Research (BMBF) and carried out by 12 departments from German universities and major research institutions and one partner from Switzerland. The scientists participating in ENTRIA represent natural sciences, civil engineering, philosophy, law, social and political sciences, and technology assessment. Recognizing that all these disciplines need to interact when radioactive waste management is concerned, the project aims at investigating and developing evaluation principles for three options to manage especially high-level radioactive waste: Deep disposal without retrievability provisions, emplacement in deep formations with monitoring and retrievability, and prolonged surface storage. While ENTRIA performs both disciplinary and interdisciplinary research, the paper focusses on the latter.

Russian joint ventures, upstream deals hit fast clip

International Nuclear Information System (INIS)

Anon.

1992-01-01

This paper reports that Russia is stepping up the pace of joint ventures and imports of petroleum technology and hardware. Among the latest action: Polar Lights, a 50-50 venture of Conoco Timan-Pechora Ltd. and Arkhangelskgeologia (AAG), started drilling in the first new-field oil-development project in Russia to include a US partner; The governments of Oman and the Kazakhstan republic signed an agreement covering oil and gas exploration, field development, and production in Kazakhstan; Phibro Energy Inc., Greenwich, Conn., last week reported the sale and delivery of the first full cargo of Russian crude oil produced and exported by a Russian-American joint venture; Era Aviation Inc., Anchorage, Alas., is sending two helicopters with crewmen to Russia to help assess the feasibility of oil and gas development off Sakhalin Island; In deals involving Canadian companies, SNC-Lavalin Inc., Montreal, received a contract for initial work on a $350 million (US) modernization of the Volvograd refinery in southern Russia

Contrast-enhanced power Doppler ultrasonography of the metacarpophalangeal joints in rheumatoid arthritis

DEFF Research Database (Denmark)

Szkudlarek, Marcin; Court-Payen, Michel; Strandberg, Charlotte

2003-01-01

The aim of this study was to examine, with dynamic contrast-enhanced MRI as the reference, if contrast-enhanced power Doppler ultrasonography (CE PDUS) of rheumatoid arthritis (RA) metacarpophalangeal (MCP) joints provides additional information for evaluation of synovial inflammation compared...... with PDUS. One MCP joint in each of 15 RA patients and 3 healthy control persons were examined with PDUS before and after intravenous bolus Levovist contrast injection. Corresponding rates of early synovial enhancement (RESE), previously shown to be closely related to histopathological synovitis, were...... calculated from dynamic contrast-enhanced MR images obtained the same day. Prior to ultrasonography, the joint was evaluated clinically. Levovist increased the flow signal in 7 of 9 joints with pre-contrast flow-signal and in 0 of 9 without pre-contrast signal. No healthy controls showed CE PDUS signal...

Epilepsia partialis continua present with shoulder joint-trunk-hip joint rhythmic clonic seizure: a case report

Directory of Open Access Journals (Sweden)

Lv YD

2016-09-01

Full Text Available Yudan Lv, Zan Wang, Fengna Chu, Chang Liu, Hongmei Meng Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, ChangChun, People’s Republic of China Abstract: Epilepsia partialis continua (EPC is a particular type of epilepsy which is distinguished from “common epilepsy” by its characteristic semiological features. However, unusual manifestations should be described in order to give awareness at clinical diagnosis. In this case report we describe a rare EPC case not previously reported, in which left shoulder joint-trunk-hip joint jerk was present for 1 week. Abnormal electroencephalogram and cerebrospinal fluid results supported a diagnosis of viral encephalitis. Antiepileptic treatment seemed effective. Our report emphasizes that a detailed functional anatomical analysis and synchronized electroencephalogram discharge should be done to avoid misdiagnosis in patients with synchronic shoulder-trunk-hip jerk symptoms. Keywords: EPC, shoulder-trunk-hip, EEG, clonic seizure, virus encephalitis

Joint resistance measurements of pancake and terminal joints for JT-60SA EF coils

Energy Technology Data Exchange (ETDEWEB)

Obana, Tetsuhiro, E-mail: obana.tetsuhiro@LHD.nifs.ac.jp [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Takahata, Kazuya; Hamaguchi, Shinji; Mito, Toshiyuki; Imagawa, Shinsaku [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Kizu, Kaname; Murakami, Haruyuki; Yoshida, Kiyoshi [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan)

2013-11-15

Highlights: • To evaluate the joint fabrication technology for the JT-60SA EF coils, joint resistance measurements were conducted with a joint sample. • The joint sample was composed of pancake and terminal joints. • The measurements demonstrated that both joints fulfilled the design requirement. • Considering the measurements, the characteristics of both joints were investigated using an analytical model that represents the joints. -- Abstract: To evaluate the joint fabrication technology for the JT-60SA EF coils, joint resistance measurements were conducted using a sample consisting of pancake and terminal joints. Both joints are shake-hands lap joints composed of cable-in-conduit conductors and a pure copper saddle-shaped spacer. The measurements demonstrated that both joints fulfilled the design requirement. Considering these measurements, the characteristics of both joints were investigated using analytical models that represent the joints. The analyses indicated that the characteristics of the conductors used in the joints affect the characteristics of the joints.

Joint instability and osteoarthritis.

Science.gov (United States)

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.

Are the Kinematics of the Knee Joint Altered during the Loading Response Phase of Gait in Individuals with Concurrent Knee Osteoarthritis and Complaints of Joint Instability? A Dynamic Stereo X-ray Study

Science.gov (United States)

Farrokhi, Shawn; Tashman, Scott; Gil, Alexandra B.; Klatt, Brian A.; Fitzgerald, G. Kelley

2011-01-01

Background Joint instability has been suggested as a risk factor for knee osteoarthritis and a cause of significant functional declines in those with symptomatic disease. However, the relationship between altered knee joint mechanics and self-reports of instability in individuals with knee osteoarthritis remains unclear. Methods Fourteen subjects with knee osteoarthritis and complaints of joint instability and 12 control volunteers with no history of knee disease were recruited for this study. Dynamic stereo X-ray technology was used to assess the three-dimensional kinematics of the knee joint during the loading response phase of gait. Findings Individuals with concurrent knee osteoarthritis and joint instability demonstrated significantly reduced flexion and internal/external rotation knee motion excursions during the loading response phase of gait (P knee joint at initial contact was significantly different (P knee osteoarthritis and joint instability. However, the anteroposterior and mediolateral tibiofemoral joint positions at initial contact and the corresponding total joint translations were similar between groups during the loading phase of gait. Interpretations The rotational patterns of tibiofemoral joint motion and joint alignments reported for individuals with concurrent knee osteoarthritis and joint instability are consistent with those previously established for individuals with knee osteoarthritis. Furthermore, the findings of similar translatory tibiofemoral motion between groups suggest that self-reports of episodic joint instability in individuals with knee osteoarthritis may not necessarily be associated with adaptive alterations in joint arthrokinematics. PMID:22071429

Are the kinematics of the knee joint altered during the loading response phase of gait in individuals with concurrent knee osteoarthritis and complaints of joint instability? A dynamic stereo X-ray study.

Science.gov (United States)

Farrokhi, Shawn; Tashman, Scott; Gil, Alexandra B; Klatt, Brian A; Fitzgerald, G Kelley

2012-05-01

Joint instability has been suggested as a risk factor for knee osteoarthritis and a cause of significant functional decline in those with symptomatic disease. However, the relationship between altered knee joint mechanics and self-reports of instability in individuals with knee osteoarthritis remains unclear. Fourteen subjects with knee osteoarthritis and complaints of joint instability and 12 control volunteers with no history of knee disease were recruited for this study. Dynamic stereo X-ray technology was used to assess the three-dimensional kinematics of the knee joint during the loading response phase of gait. Individuals with concurrent knee osteoarthritis and joint instability demonstrated significantly reduced flexion and internal/external rotation knee motion excursions during the loading response phase of gait (Pknee joint at initial contact was significantly different (Pknee osteoarthritis and joint instability. However, the anteroposterior and mediolateral tibiofemoral joint positions at initial contact and the corresponding total joint translations were similar between groups during the loading phase of gait. The rotational patterns of tibiofemoral joint motion and joint alignments reported for individuals with concurrent knee osteoarthritis and joint instability are consistent with those previously established for individuals with knee osteoarthritis. Furthermore, the findings of similar translatory tibiofemoral motion between groups suggest that self-reports of episodic joint instability in individuals with knee osteoarthritis may not necessarily be associated with adaptive alterations in joint arthrokinematics. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effects of walking speed on the step-by-step control of step width.

Science.gov (United States)

Stimpson, Katy H; Heitkamp, Lauren N; Horne, Joscelyn S; Dean, Jesse C

2018-02-08

Young, healthy adults walking at typical preferred speeds use step-by-step adjustments of step width to appropriately redirect their center of mass motion and ensure mediolateral stability. However, it is presently unclear whether this control strategy is retained when walking at the slower speeds preferred by many clinical populations. We investigated whether the typical stabilization strategy is influenced by walking speed. Twelve young, neurologically intact participants walked on a treadmill at a range of prescribed speeds (0.2-1.2 m/s). The mediolateral stabilization strategy was quantified as the proportion of step width variance predicted by the mechanical state of the pelvis throughout a step (calculated as R 2 magnitude from a multiple linear regression). Our ability to accurately predict the upcoming step width increased over the course of a step. The strength of the relationship between step width and pelvis mechanics at the start of a step was reduced at slower speeds. However, these speed-dependent differences largely disappeared by the end of a step, other than at the slowest walking speed (0.2 m/s). These results suggest that mechanics-dependent adjustments in step width are a consistent component of healthy gait across speeds and contexts. However, slower walking speeds may ease this control by allowing mediolateral repositioning of the swing leg to occur later in a step, thus encouraging slower walking among clinical populations with limited sensorimotor control. Published by Elsevier Ltd.

Joint Instability and Osteoarthritis

Directory of Open Access Journals (Sweden)

Darryl Blalock

2015-01-01

Full Text Available 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.

The effect of sacroiliac joint mobilization on pelvic deformation and the static balance ability of female university students with si joint dysfunction.

Science.gov (United States)

Son, Jeong-Hyun; Park, Gi Duck; Park, Hoo Sung

2014-06-01

[Purpose] The present study aimed to determine the effect of an 8-week program of joint mobilization on changes in pelvic obliquity and pain level in seventeen female university students aged in their 20's with sacroiliac joint dysfunction by dividing them into two groups: a joint mobilization group (MWM) and a control group. [Subjects] Seventeen subjects were selected from female university students aged in their 20's attending N University in Cheon-An City, Korea, The subjects had sacroiliac joint syndrome, but experienced no problems with daily living and had no previous experience of joint mobilization exercise. The subjects were randomly assigned to a joint mobilization group of eight and a control group of nine who performed joint mobilization exercise. [Methods] Body fat and lean body mass were measured using InBody 7.0 (Biospace, Korea). The Direct Segmental Multi-frequency Bioelectrical Impedance Analysis Method (DSM-BIA) was used for body composition measurement. A pressure footstool (Pedoscan, DIERS, Germany) and a trunk measurement system (Formetric 4D, DIERS, Germany), a 3D image processing apparatus with high resolution for vertebrae, were used to measure 3D trunk images of the vertebrae and pelvis obliquity, as well as static balance ability. [Result] The MWM group showed a significantly better Balance than the control group. In addition, the results of the left/right and the front/rear balance abilities were significantly better than those of the control group. [Conclusion] This study proved that a combination of mobilization with movement and functional training was effective in reducing pelvis malposition and pain, and improving static stability control.

International joint ventures

DEFF Research Database (Denmark)

Sørensen, Karsten Engsig

2001-01-01

The article analysis problems connected with corporate joint ventures. Among others the possible conflicts between the joint venture agreement and the statutes of the companies is examined, as well as certain problems connected to the fact that the joint venture partners have created commen control...... over their joint company....

Condylar Joint Fusion and Stabilization (by Screws and Plates) in Nontraumatic Atlanto-Occipital Dislocation: Technical Report of 2 Cases.

Science.gov (United States)

Chowdhury, Forhad H; Haque, Mohammod Raziul; Alam, Sarwar Murshed; Khaled Chowdhury, S M Noman; Khan, Shamsul Islam; Goel, Atul

2017-11-01

Nontraumatic spontaneous atlanto-occipital dislocation (AOD) is rare. In this report, we discuss the technical steps of condylar joint fusion and stabilization (by screws and plates) in nontraumatic AOD. To the best of our knowledge, it is the first report of such techniques. A young girl and a young man with progressive quadriparesis due to nontraumatic spontaneous atlanto-occipital dislocation were managed by microsurgical reduction, fusion, and stabilization of the joint by occipital condylar and C1 lateral mass screw and plate fixation after mobilization of vertebral artery. In both cases, condylar joints fixation and fusion were done successfully. Condylar joint stabilization and fusion may be a good or alternative option for AOD. Copyright © 2017 Elsevier Inc. All rights reserved.

Tuberculosis of the joints of the hands and feet

International Nuclear Information System (INIS)

Eckel, H.; Duee, K.

1985-01-01

Eighty-nine patients with tuberculosis of joints in the hands or feet have been examined. There has been a change in the peak incidence from adolescence to adult life. The high number of incorrect diagnoses was remarkable (45% in our own patients). A previous tuberculous infection was found in 40% of the patients. Osteoporosis, or bone atrophy, are important radiological signs for the early diagnosis and follow-up of articular tuberculosis. The later phase is characterised by narrowing of joint spaces. Later still there is destruction of subchondral lamellae and fusion of the carpal and tarsal bones, resulting in changes of shape and position. (orig.) [de

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

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Skip to main content (Press Enter). Toggle navigation Joint Chiefs of Staff Joint Chiefs of Staff Joint Chiefs of Staff Facebook Twitter YouTube Flickr Blog Instagram Search JCS: Search Search Search JCS: Search Home Media News Photos Videos Publications About The Joint Staff Chairman Vice Chairman

A joint-constraint model for human joints using signed distance-fields

DEFF Research Database (Denmark)

Engell-Nørregård, Morten Pol; Abel, Sarah Maria Niebe; Erleben, Kenny

2012-01-01

We present a local joint-constraint model for a single joint which is based on distance fields. Our model is fast, general, and well suited for modeling human joints. In this work, we take a geometric approach and model the geometry of the boundary of the feasible region, i.e., the boundary of all...... allowed poses. A region of feasible poses can be built by embedding motion captured data points in a signed distance field. The only assumption is that the feasible poses form a single connected set of angular values. We show how signed distance fields can be used to generate fast and general joint......-joint dependencies, or joints with more than three degrees of freedom. The resolution of the joint-constraints can be tweaked individually for each degree of freedom, which can be used to optimize memory usage. We perform a comparative study of the key-properties of various joint-constraint models, as well...

Optical characterization of gold chains and steps on the vicinal Si(557) surface: Theory and experiment

Energy Technology Data Exchange (ETDEWEB)

Hogan, Conor [Consiglio Nazionale delle Ricerche, Istituto di Struttura della Materia, via Fosso del Cavaliere 100, 00133 Rome (Italy); Department of Physics and European Theoretical Spectroscopy Facility (ETSF), University of Rome ' ' Tor Vergata' ' , Via della Ricerca Scientifica 1, 00133 Rome (Italy); McAlinden, Niall; McGilp, John F. [School of Physics, Trinity College Dublin, Dublin 2 (Ireland)

2012-06-15

We present a joint experimental-theoretical study of the reflectance anisotropy of clean and gold-covered Si(557), a vicinal surface of Si(111) upon which gold forms quasi-one-dimensional (1D) chains parallel to the steps. By means of first-principles calculations, we analyse the close relationship between the various surface structural motifs and the optical properties. Good agreement is found between experimental and computed spectra of single-step models of both clean and Au-adsorbed surfaces. Spectral fingerprints of monoatomic gold chains and silicon step edges are identified. The role of spin-orbit coupling (SOC) on the surface optical properties is examined, and found to have little effect. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Estimation of Joint types and Joint Limits from Motion capture data

DEFF Research Database (Denmark)

Engell-Nørregård, Morten Pol; Erleben, Kenny

2009-01-01

It is time-consuming for an animator to explicitly model joint types and joint limits of articulated figures. In this paper we describe a simple and fast approach to automated joint estimation from motion capture data of articulated figures. Our method will make the joint modeling more efficient ...

Radiofrequency denervation of the hip joint for pain management: case report and literature review.

Science.gov (United States)

Gupta, Gaurav; Radhakrishna, Mohan; Etheridge, Paul; Besemann, Markus; Finlayson, Robert J

2014-01-01

A 55-year-old male presented with severe pain and functional limitations as a result of left hip osteoarthritis. He had failed multiple treatments while waiting for a hip arthroplasty, including physical therapy, medications, and various intra-articular injections. Thermal radiofrequency lesioning of the obturator and femoral articular branches to the hip joint was offered in the interim. To our knowledge, this is the first report to describe an inferior-lateral approach for lesioning the obturator branch, the clinical application of successive lesions to increase denervation area, and outcomes in a patient receiving a second treatment with previously good results. To discuss relevant and technical factors for this specific case, we reviewed previous literature on hip joint radiofrequency and critically evaluated previous anatomic studies in the context of radiofrequency. The first treatment provided significant benefit for a period of 6 months. A second treatment was employed providing only mild to moderate benefit until his joint replacement surgery 4 months later. Literature review revealed studies of low quality secondary to small sample sizes, patient selection methodology, inclusion of patients with heterogenous etiologies for pain, variable needle placement techniques, and lack of measurement of functional outcomes. Case report and low quality studies in existing literature. Hip joint radiofrequency denervation is a promising avenue for adjunctive treatment of hip pain. Further cadaveric studies are required to clarify a multitude of technical parameters. Once these are well defined, future clinical studies should consider pain, functional, and economic outcomes in their design.

Free Modal Algebras Revisited: The Step-by-Step Method

NARCIS (Netherlands)

Bezhanishvili, N.; Ghilardi, Silvio; Jibladze, Mamuka

2012-01-01

We review the step-by-step method of constructing finitely generated free modal algebras. First we discuss the global step-by-step method, which works well for rank one modal logics. Next we refine the global step-by-step method to obtain the local step-by-step method, which is applicable beyond

Simulating Dynamics of the System of Articulated Rigid Bodies with Joint Friction

Directory of Open Access Journals (Sweden)

M. V. Michaylyuk

2016-01-01

Full Text Available The subject of the work is to simulate dynamics of the system of articulated rigid bodies in the virtual environment complexes. The work aim is to develop algorithms and methods to simulate the multi-body system dynamics with joint friction to ensure all calculations in real time in line with visual realistic behavior of objects in a scene.The paper describes the multibody system based on a maximal set of coordinates, and to simulate the joint friction is used a Coulomb's law of dry friction. Joints are described using the holonomic constraints and their derivatives that specify the constraints on velocities of joined bodies. Based on The Coulomb’s law a correlation for the friction impulse values has been derived as an inequality. If the friction impulse performs a constraint that is a lack of relative motion of two joint-joined bodies, there is a static friction in the joint. Otherwise, there is a dynamic friction in the joint. Using a semi-implicit Euler method allows us to describe dynamics of articulated rigid bodies with joint friction as a system of linear algebraic equations and inequalities for the unknown velocities and impulse values.To solve the obtained system of equations and inequalities is used an iterative method of sequential impulses, which sequentially processes constraints for each joint with impulse calculation and its application to the joined bodies rather than considers the entire system. To improve the method convergence, at each iteration the calculated impulses are accumulated for their further using as an initial approximation at the next step of simulation.The proposed algorithms and methods have been implemented in the training complex dynamics subsystem, developed in SRISA RAS. Evaluation of these methods and algorithms has demonstrated their full adequacy to requirements for virtual environment systems and training complexes.

SYSTEMATIZATION OF THE BASIC STEPS OF THE STEP-AEROBICS

Directory of Open Access Journals (Sweden)

Darinka Korovljev

2011-03-01

Full Text Available Following the development of the powerful sport industry, in front of us appeared a lot of new opportunities for creating of the new programmes of exercising with certain requisites. One of such programmes is certainly step-aerobics. Step-aerobics can be defined as a type of aerobics consisting of the basic aerobic steps (basic steps applied in exercising on stepper (step bench, with a possibility to regulate its height. Step-aerobics itself can be divided into several groups, depending on the following: type of music, working methods and adopted knowledge of the attendants. In this work, the systematization of the basic steps in step-aerobics was made on the basis of the following criteria: steps origin, number of leg motions in stepping and relating the body support at the end of the step. Systematization of the basic steps of the step-aerobics is quite significant for making a concrete review of the existing basic steps, thus making creation of the step-aerobics lesson easier

Temporomandibular joint dislocation due to acute propranolol intoxication

Directory of Open Access Journals (Sweden)

Abbas Aghabiklooei

2010-07-01

Full Text Available Abbas Aghabiklooei1, Homan Elahi2, Babak Mostafazadeh31Department of Medical Toxicology and Forensic Medicine, Iran University of Medical Sciences, Tehran, Iran; 2Firouzgar Hospital, Department of ENT, Tehran, Iran; 3Department of Medical Toxicology and Forensic Medicine, Shaheed Beheshty University of Medical Sciences, Tehran, IranAbstract: Temporomandibular joint (TMJ dislocation has not previously been reported as a complication of beta-blocker toxicity. We are reporting two cases of TMJ dislocation resulted from acute severe intoxication with pure propranolol (PPL for the first time. Bilateral TMJ dislocation happened in two patients who were admitted to intensive care unit with diagnosis of severe acute PPL toxicity. Clinical diagnosis of TMJ dislocation was obtained by physical examination. Successful reduction was performed for both patients without subsequent recurrence in two weeks following hospital discharge. Both of our subjects had no previous history of lower jaw dislocation. There was not any risk factor for dislocation such as convulsion during admission period, recent face trauma, or oral manipulation by the medical team. This study showed that TMJ dislocation may occur after severe acute PPL toxicity probably due to spastic contraction of the lateral pterygoid muscle. This is against previously mentioned hypothesis that stated masseteric muscles contraction as the main cause of a bilateral dislocated TMJ.Keywords: propranolol, toxicity, temporomandibular joint dislocation

Influence of step rate and quadriceps load distribution on patellofemoral cartilage contact pressures during running.

Science.gov (United States)

Lenhart, Rachel L; Smith, Colin R; Vignos, Michael F; Kaiser, Jarred; Heiderscheit, Bryan C; Thelen, Darryl G

2015-08-20

Interventions used to treat patellofemoral pain in runners are often designed to alter patellofemoral mechanics. This study used a computational model to investigate the influence of two interventions, step rate manipulation and quadriceps strengthening, on patellofemoral contact pressures during running. Running mechanics were analyzed using a lower extremity musculoskeletal model that included a knee with six degree-of-freedom tibiofemoral and patellofemoral joints. An elastic foundation model was used to compute articular contact pressures. The lower extremity model was scaled to anthropometric dimensions of 22 healthy adults, who ran on an instrumented treadmill at 90%, 100% and 110% of their preferred step rate. Numerical optimization was then used to predict the muscle forces, secondary tibiofemoral kinematics and all patellofemoral kinematics that would generate the measured primary hip, knee and ankle joint accelerations. Mean and peak patella contact pressures reached 5.0 and 9.7MPa during the midstance phase of running. Increasing step rate by 10% significantly reduced mean contact pressures by 10.4% and contact area by 7.4%, but had small effects on lateral patellar translation and tilt. Enhancing vastus medialis strength did not substantially affect pressure magnitudes or lateral patellar translation, but did shift contact pressure medially toward the patellar median ridge. Thus, the model suggests that step rate tends to primarily modulate the magnitude of contact pressure and contact area, while vastus medialis strengthening has the potential to alter mediolateral pressure locations. These results are relevant to consider in the design of interventions used to prevent or treat patellofemoral pain in runners. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluating the Relationship between Team Performance and Joint Attention with Longitudinal Multivariate Mixed Models

Science.gov (United States)

2016-09-23

Sweller, J. (2005). Cognitive load theory and complex learning: Recent developments and future directions. Educational Psychology Review, 17(2), 147–177...Relationship between Team Performance and Joint Attention with Longitudinal Multivariate Mixed Models 5a. CONTRACT NUMBER FA8650-14-D-6501-0009 5b...Annual Meeting, 19-23 September 2016. 14. Previous research indicates that measures of joint attention provide unique insight into team cognition

Visual and kinesthetic locomotor imagery training integrated with auditory step rhythm for walking performance of patients with chronic stroke.

Science.gov (United States)

Kim, Jin-Seop; Oh, Duck-Won; Kim, Suhn-Yeop; Choi, Jong-Duk

2011-02-01

To compare the effect of visual and kinesthetic locomotor imagery training on walking performance and to determine the clinical feasibility of incorporating auditory step rhythm into the training. Randomized crossover trial. Laboratory of a Department of Physical Therapy. Fifteen subjects with post-stroke hemiparesis. Four locomotor imagery trainings on walking performance: visual locomotor imagery training, kinesthetic locomotor imagery training, visual locomotor imagery training with auditory step rhythm and kinesthetic locomotor imagery training with auditory step rhythm. The timed up-and-go test and electromyographic and kinematic analyses of the affected lower limb during one gait cycle. After the interventions, significant differences were found in the timed up-and-go test results between the visual locomotor imagery training (25.69 ± 16.16 to 23.97 ± 14.30) and the kinesthetic locomotor imagery training with auditory step rhythm (22.68 ± 12.35 to 15.77 ± 8.58) (P kinesthetic locomotor imagery training exhibited significantly increased activation in a greater number of muscles and increased angular displacement of the knee and ankle joints compared with the visual locomotor imagery training, and these effects were more prominent when auditory step rhythm was integrated into each form of locomotor imagery training. The activation of the hamstring during the swing phase and the gastrocnemius during the stance phase, as well as kinematic data of the knee joint, were significantly different for posttest values between the visual locomotor imagery training and the kinesthetic locomotor imagery training with auditory step rhythm (P kinesthetic locomotor imagery training than in the visual locomotor imagery training. The auditory step rhythm together with the locomotor imagery training produces a greater positive effect in improving the walking performance of patients with post-stroke hemiparesis.

Analysis of movement axes of the ankle and subtalar joints: relationship with the articular surfaces of the talus.

Science.gov (United States)

Cho, Ho-Jung; Kwak, Dai-Soon; Kim, In-Beom

2014-10-01

Bone shape varies among human populations, and in the case of articular joints, the shape of the articulating surfaces strongly influences joint movement. In this study, we aimed to analyse the axes of the talocrural and subtalar joints, using the talar articular surface method, and compare these results with those of the previous studies. We used three-dimensional reconstruction models of tali among Korean individuals. The axes of the talocrural and subtalar joints were calculated by using the least-square sphere fitting method, and the principal axis was used for reference coordination. The shape of the talus was classified based on the shape of its anterior, middle, and posterior calcaneal facets, and the talar shape was compared with the movement axes. The movement axes did not differ according to the type of calcaneal facets of the talus. Interestingly, we also noted that the axes of the talocrural and subtalar joints in this study differed significantly from those reported in the previous studies; these differences may be due to variations in the shape of the bones. © IMechE 2014.

Validation of BS7910:2005 failure assessment diagrams for cracked square hollow section T-, Y- and K-joints

International Nuclear Information System (INIS)

Lie, S.T.; Yang, Z.M.; Gho, W.M.

2009-01-01

This paper describes the usage of finite element (FE) analyses results to validate the standard BS7910 assessment procedure for the safe design of cracked square hollow section (SHS) T-, Y- and K-joints. In the study, the actual 3D surface cracks obtained from previous fatigue tests have been included in the FE models. An automatic mesh generation program is then developed and used to produce the failure assessment diagram (FAD) through the J-integral method. The ultimate strength of uncracked SHS joints with reduced load bearing areas have been referenced to derive the plastic collapse loads of cracked SHS joints for the development of FAD. These loads have been validated against the previous experimental results. In comparison with the existing standard BS7910 Level 2A/3A FAD curve and the proposed assessment procedure for circular hollow section joints, it is found that a plastic collapse load with a penalty factor of 1.05 will be sufficient for the safe assessment of cracked SHS T, Y, and K-joints under brace end axial loading

Symplectic integrators with adaptive time steps

Science.gov (United States)

Richardson, A. S.; Finn, J. M.

2012-01-01

In recent decades, there have been many attempts to construct symplectic integrators with variable time steps, with rather disappointing results. In this paper, we identify the causes for this lack of performance, and find that they fall into two categories. In the first, the time step is considered a function of time alone, Δ = Δ(t). In this case, backward error analysis shows that while the algorithms remain symplectic, parametric instabilities may arise because of resonance between oscillations of Δ(t) and the orbital motion. In the second category the time step is a function of phase space variables Δ = Δ(q, p). In this case, the system of equations to be solved is analyzed by introducing a new time variable τ with dt = Δ(q, p) dτ. The transformed equations are no longer in Hamiltonian form, and thus do not benefit from integration methods which would be symplectic for Hamiltonian systems. We analyze two methods for integrating the transformed equations which do, however, preserve the structure of the original equations. The first is an extended phase space method, which has been successfully used in previous studies of adaptive time step symplectic integrators. The second, novel, method is based on a non-canonical mixed-variable generating function. Numerical trials for both of these methods show good results, without parametric instabilities or spurious growth or damping. It is then shown how to adapt the time step to an error estimate found by backward error analysis, in order to optimize the time-stepping scheme. Numerical results are obtained using this formulation and compared with other time-stepping schemes for the extended phase space symplectic method.

An Iterative Ensemble Kalman Filter with One-Step-Ahead Smoothing for State-Parameters Estimation of Contaminant Transport Models

KAUST Repository

Gharamti, M. E.; Ait-El-Fquih, Boujemaa; Hoteit, Ibrahim

2015-01-01

Numerical experiments are conducted with a two-dimensional synthetic subsurface transport model simulating the migration of a contaminant plume in a heterogenous aquifer domain. Contaminant concentration data are assimilated to estimate both the contaminant state and the hydraulic conductivity field. Assimilation runs are performed under imperfect modeling conditions and various observational scenarios. Simulation results suggest that the proposed scheme efficiently recovers both the contaminant state and the aquifer conductivity, providing more accurate estimates than the standard Joint and Dual EnKFs in all tested scenarios. Iterating on the update step of the new scheme further enhances the proposed filter’s behavior. In term of computational cost, the new Joint-EnKF is almost equivalent to that of the Dual-EnKF, but requires twice more model integrations than the standard Joint-EnKF.

Accurate step-hold tracking of smoothly varying periodic and aperiodic probability.

Science.gov (United States)

Ricci, Matthew; Gallistel, Randy

2017-07-01

Subjects observing many samples from a Bernoulli distribution are able to perceive an estimate of the generating parameter. A question of fundamental importance is how the current percept-what we think the probability now is-depends on the sequence of observed samples. Answers to this question are strongly constrained by the manner in which the current percept changes in response to changes in the hidden parameter. Subjects do not update their percept trial-by-trial when the hidden probability undergoes unpredictable and unsignaled step changes; instead, they update it only intermittently in a step-hold pattern. It could be that the step-hold pattern is not essential to the perception of probability and is only an artifact of step changes in the hidden parameter. However, we now report that the step-hold pattern obtains even when the parameter varies slowly and smoothly. It obtains even when the smooth variation is periodic (sinusoidal) and perceived as such. We elaborate on a previously published theory that accounts for: (i) the quantitative properties of the step-hold update pattern; (ii) subjects' quick and accurate reporting of changes; (iii) subjects' second thoughts about previously reported changes; (iv) subjects' detection of higher-order structure in patterns of change. We also call attention to the challenges these results pose for trial-by-trial updating theories.

Echinocandin Failure Case Due to a Previously Unreported FKS1 Mutation in Candida krusei

DEFF Research Database (Denmark)

Jensen, Rasmus Hare; Justesen, Ulrik Stenz; Rewes, Annika

2014-01-01

Echinocandins are the preferred therapy for invasive infections due to Candida krusei. We present here a case of clinical failure involving C. krusei with a characteristic FKS1 hot spot mutation not previously reported in C. krusei that was isolated after 14 days of treatment. Anidulafungin MICs...... were elevated by ≥5 dilution steps above the clinical breakpoint but by only 1 step for a Candida albicans isolate harboring the corresponding mutation, suggesting a notable species-specific difference in the MIC increase conferred by this mutation....

Lateral step initiation behavior in older adults.

Science.gov (United States)

Sparto, Patrick J; Jennings, J Richard; Furman, Joseph M; Redfern, Mark S

2014-02-01

Older adults have varied postural responses during induced and voluntary lateral stepping. The purpose of the research was to quantify the occurrence of different stepping strategies during lateral step initiation in older adults and to relate the stepping responses to retrospective history of falls. Seventy community-ambulating older adults (mean age 76 y, range 70-94 y) performed voluntary lateral steps as quickly as possible to the right or left in response to a visual cue, in a blocked design. Vertical ground reaction forces were measured using a forceplate, and the number and latency of postural adjustments were quantified. Subjects were assigned to groups based on their stepping strategy. The frequency of trials with one or two postural adjustments was compared with data from 20 younger adults (mean age 38 y, range 21-58 y). Logistic regression was used to relate presence of a fall in the previous year with the number and latency of postural adjustments. In comparison with younger adults, who almost always demonstrated one postural adjustment when stepping laterally, older adults constituted a continuous distribution in the percentage of step trials made with one postural adjustment (from 0% to 100% of trials). Latencies of the initial postural adjustment and foot liftoff varied depending on the number of postural adjustments made. A history of falls was associated a larger percentage of two postural adjustments, and a longer latency of foot liftoff. In conclusion, the number and latency of postural adjustments made during voluntary lateral stepping provides additional evidence that lateral control of posture may be a critical indicator of aging. Copyright © 2013 Elsevier B.V. All rights reserved.

A 'joint venture' model of recontacting in clinical genomics: challenges for responsible implementation.

Science.gov (United States)

Dheensa, Sandi; Carrieri, Daniele; Kelly, Susan; Clarke, Angus; Doheny, Shane; Turnpenny, Peter; Lucassen, Anneke

2017-07-01

Advances in genomics often lead healthcare professionals (HCPs) to learn new information, e.g., about reinterpreted variants that could have clinical significance for patients seen previously. A question arises of whether HCPs should recontact these former patients. We present some findings interrogating the views of patients (or parents of patients) with a rare or undiagnosed condition about how such recontacting might be organised ethically and practically. Forty-one interviews were analysed thematically. Participants suggested a 'joint venture' model in which efforts to recontact are shared with HCPs. Some proposed an ICT-approach involving an electronic health record that automatically alerts them to potentially relevant updates. The need for rigorous privacy controls and transparency about who could access their data was emphasised. Importantly, these findings highlight that the lack of clarity about recontacting is a symptom of a wider problem: the lack of necessary infrastructure to pool genomic data responsibly, to aggregate it with other health data, and to enable patients/parents to receive updates. We hope that our findings will instigate a debate about the way responsibilities for recontacting under any joint venture model could be allocated, as well as the limitations and normative implications of using ICT as a solution to this intractable problem. As a first step to delineating responsibilities in the clinical setting, we suggest HCPs should routinely discuss recontacting with patients/parents, including the new information that should trigger a HCP to initiate recontact, as part of the consent process for genetic testing. Copyright © 2017 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

Evaluation of an intact, an ACL-deficient, and a reconstructed human knee joint finite element model.

Science.gov (United States)

Vairis, Achilles; Stefanoudakis, George; Petousis, Markos; Vidakis, Nectarios; Tsainis, Andreas-Marios; Kandyla, Betina

2016-02-01

The human knee joint has a three-dimensional geometry with multiple body articulations that produce complex mechanical responses under loads that occur in everyday life and sports activities. Understanding the complex mechanical interactions of these load-bearing structures is of use when the treatment of relevant diseases is evaluated and assisting devices are designed. The anterior cruciate ligament (ACL) in the knee is one of four main ligaments that connects the femur to the tibia and is often torn during sudden twisting motions, resulting in knee instability. The objective of this work is to study the mechanical behavior of the human knee joint and evaluate the differences in its response for three different states, i.e., intact, ACL-deficient, and surgically treated (reconstructed) knee. The finite element models corresponding to these states were developed. For the reconstructed model, a novel repair device was developed and patented by the author in previous work. Static load cases were applied, as have already been presented in a previous work, in order to compare the calculated results produced by the two models the ACL-deficient and the surgically reconstructed knee joint, under the exact same loading conditions. Displacements were calculated in different directions for the load cases studied and were found to be very close to those from previous modeling work and were in good agreement with experimental data presented in literature. The developed finite element model for both the intact and the ACL-deficient human knee joint is a reliable tool to study the kinematics of the human knee, as results of this study show. In addition, the reconstructed human knee joint model had kinematic behavior similar to the intact knee joint, showing that such reconstruction devices can restore human knee stability to an adequate extent.

Fluid extravasation of the articular capsule as a complication of temporomandibular joint pumping and perfusion

Energy Technology Data Exchange (ETDEWEB)

Sasaki, Kenichi; Watahiki, Ryuichirou; Tamura, Hidetoshi; Ogura, Motoi; Shibuya, Masayuki [Kameda General Hospital, Kamogawa, Chiba (Japan)

2002-11-01

This report is a retrospective study of fluid extravasation as a complication of temporomandibular joint pumping and perfusion. Contrast-enhanced 3D-CT of the upper joint compartment was performed for presurgical diagnosis before temporomandibular joint arthroscopic surgery in our hospital from 1996 to 2000. From these cases, 43 joints and 38 patients were selected because they had not improved under conservative treatment during the previous six months. Fluid extravasation of the articular capsule was recognized in 9 joints (20.9%) in 9 patients, 3 males and 6 females. Two of the nine patients had undergone arthroscopic observation before surgery. This test had revealed only thin articular capsule, not a perforation, in any of these cases. The data indicate only extremely tiny perforations or infiltration leakage due to the fluid pressure in the upper joint compartment during pumping or perfusion. Oral and maxillofacial surgeons should be aware of this complication. (author)

Typing DNA profiles from previously enhanced fingerprints using direct PCR.

Science.gov (United States)

Templeton, Jennifer E L; Taylor, Duncan; Handt, Oliva; Linacre, Adrian

2017-07-01

Fingermarks are a source of human identification both through the ridge patterns and DNA profiling. Typing nuclear STR DNA markers from previously enhanced fingermarks provides an alternative method of utilising the limited fingermark deposit that can be left behind during a criminal act. Dusting with fingerprint powders is a standard method used in classical fingermark enhancement and can affect DNA data. The ability to generate informative DNA profiles from powdered fingerprints using direct PCR swabs was investigated. Direct PCR was used as the opportunity to generate usable DNA profiles after performing any of the standard DNA extraction processes is minimal. Omitting the extraction step will, for many samples, be the key to success if there is limited sample DNA. DNA profiles were generated by direct PCR from 160 fingermarks after treatment with one of the following dactyloscopic fingerprint powders: white hadonite; silver aluminium; HiFi Volcano silk black; or black magnetic fingerprint powder. This was achieved by a combination of an optimised double-swabbing technique and swab media, omission of the extraction step to minimise loss of critical low-template DNA, and additional AmpliTaq Gold ® DNA polymerase to boost the PCR. Ninety eight out of 160 samples (61%) were considered 'up-loadable' to the Australian National Criminal Investigation DNA Database (NCIDD). The method described required a minimum of working steps, equipment and reagents, and was completed within 4h. Direct PCR allows the generation of DNA profiles from enhanced prints without the need to increase PCR cycle numbers beyond manufacturer's recommendations. Particular emphasis was placed on preventing contamination by applying strict protocols and avoiding the use of previously used fingerprint brushes. Based on this extensive survey, the data provided indicate minimal effects of any of these four powders on the chance of obtaining DNA profiles from enhanced fingermarks. Copyright © 2017

A Systematic Approach to the Study of Accelerated weathering of Building Joint Sealants

Science.gov (United States)

Christopher C. White; Donald L. Hunston; Kar Tean Tan; James J. Filliben; Adam L. Pintar; Greg. Schueneman

2012-01-01

An accurate service life prediction model is needed for building joint sealants in order to greatly reduce the time to market of a new product and reduce the risk of introducing a poorly performing product into the marketplace. A stepping stone to the success of this effort is the precise control of environmental variables in a laboratory accelerated test apparatus in...

Joint Costs in Electricity and Natural Gas Distribution Infrastructures: The Role of Urban Factors

Directory of Open Access Journals (Sweden)

Muzeyyen Anil Senyel

2018-04-01

Full Text Available This paper analyzes the joint cost structure of electricity and natural gas distribution investments. Assessing the joint costs is critical for urban development and public policy regarding competition at the local level. The paper accounts for the urban and geographic factors at the local level, while the previous literature primarily used company-level data with a few or no site-specific variables in joint cost analyses. An empirical analysis of the multi-utility capital costs suggests that the local urban and geographic conditions affect such costs, with economies of scope present in electricity and natural gas both in terms of total costs and underground investment costs. Hence, the joint service provision makes economic and environmental sense for urban policy makers.

Reliability of Tubular Joints

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Thoft-Christensen, Palle

In this paper the preliminary results obtained by tests on tubular joints are presented. The joints are T-joints and the loading is static. It is the intention in continuation of these tests to perform tests on other types of joints (e.g. Y-joints) and also with dynamic loading. The purpose...... of the test is partly to obtain empirical data for the ultimate load-carrying capacity of tubular T-joints and partly to obtain some experience in performing tests with tubular joints. It is well known that tubular joints are usually designed in offshore engineering on the basis of empirical formulas obtained...... by experimental test results. Therefore, there is a need for performing experimental tests in this area....

On joint power allocation and multipath routing in femto-relay networks

OpenAIRE

Hoteit , Sahar; Duhamel , Pierre; Lasaulce , Samson

2016-01-01

International audience; —Transmit power allocation techniques are very important to manage interference in small-cell networks. While available power allocation algorithms in the literature rely on a predefined routing protocol, we propose in this paper a power-efficient two-step algorithm that allows power allocation and routing to be performed jointly in femto-relay networks. First, we propose an interference-based partitioning method to cluster the femto-relays, then we adopt an iterative ...

Experimental color encryption in a joint transform correlator architecture

International Nuclear Information System (INIS)

Tebaldi, Myrian; Amaya, Dafne; Torroba, Roberto; Horrillo, Sergi; Perez-Cabre, Elisabet; Millan, Maria S; Bolognini, Nestor

2011-01-01

We present an experimental color image encryption by using a photorefractive crystal and a joint transform correlator (JTC) architecture. We achieve the color storing by changing the illumination wavelength. One JTC aperture has the input image information corresponding to a determined color channel bonded to a random phase mask (object aperture), and the other JTC aperture contains the key code mask. The joint power spectrum is stored in a photorefractive crystal. Each color data is stored as a modulation of birefringence in this photosensitive medium. The adequate wavelength change produces a corresponding power spectrum modification that avoids image encryption cross talk in the read out step. An analysis in terms of the sensitivity of the photorefractive silenite crystal for different recording wavelengths is carried out. It should be highlighted that the multiplexed power spectrum shows neither the multiplexing operation nor the amount of stored information increasing the system security. We present experimental results that support our approach

Road network safety evaluation using Bayesian hierarchical joint model.

Science.gov (United States)

Wang, Jie; Huang, Helai

2016-05-01

Safety and efficiency are commonly regarded as two significant performance indicators of transportation systems. In practice, road network planning has focused on road capacity and transport efficiency whereas the safety level of a road network has received little attention in the planning stage. This study develops a Bayesian hierarchical joint model for road network safety evaluation to help planners take traffic safety into account when planning a road network. The proposed model establishes relationships between road network risk and micro-level variables related to road entities and traffic volume, as well as socioeconomic, trip generation and network density variables at macro level which are generally used for long term transportation plans. In addition, network spatial correlation between intersections and their connected road segments is also considered in the model. A road network is elaborately selected in order to compare the proposed hierarchical joint model with a previous joint model and a negative binomial model. According to the results of the model comparison, the hierarchical joint model outperforms the joint model and negative binomial model in terms of the goodness-of-fit and predictive performance, which indicates the reasonableness of considering the hierarchical data structure in crash prediction and analysis. Moreover, both random effects at the TAZ level and the spatial correlation between intersections and their adjacent segments are found to be significant, supporting the employment of the hierarchical joint model as an alternative in road-network-level safety modeling as well. Copyright © 2016 Elsevier Ltd. All rights reserved.

Grizzly bear (Ursus arctos horribilis) locomotion: forelimb joint mechanics across speed in the sagittal and frontal planes.

Science.gov (United States)

Shine, Catherine L; Robbins, Charles T; Nelson, O Lynne; McGowan, Craig P

2017-04-01

The majority of terrestrial locomotion studies have focused on parasagittal motion and paid less attention to forces or movement in the frontal plane. Our previous research has shown that grizzly bears produce higher medial ground reaction forces (lateral pushing from the animal) than would be expected for an upright mammal, suggesting frontal plane movement may be an important aspect of their locomotion. To examine this, we conducted an inverse dynamics analysis in the sagittal and frontal planes, using ground reaction forces and position data from three high-speed cameras of four adult female grizzly bears. Over the speed range collected, the bears used walks, running walks and canters. The scapulohumeral joint, wrist and the limb overall absorb energy (average total net work of the forelimb joints, -0.97 W kg -1 ). The scapulohumeral joint, elbow and total net work of the forelimb joints have negative relationships with speed, resulting in more energy absorbed by the forelimb at higher speeds (running walks and canters). The net joint moment and power curves maintain similar patterns across speed as in previously studied species, suggesting grizzly bears maintain similar joint dynamics to other mammalian quadrupeds. There is no significant relationship with net work and speed at any joint in the frontal plane. The total net work of the forelimb joints in the frontal plane was not significantly different from zero, suggesting that, despite the high medial ground reaction forces, the forelimb acts as a strut in that plane. © 2017. Published by The Company of Biologists Ltd.

Volatility and what Lies Beneath: A Joint Model

DEFF Research Database (Denmark)

Cont, Rama; Kokholm, Thomas

by fitting VIX option prices and then options on the underlying making the model implementable from a calibration perspective. Finally, the model is implemented and it is shown how it fits VIX index option prices along with European options on S&P 500 for various maturities.......  In this paper a model for the joint dynamics of forward variance swap prices and the underlying stock index is proposed. It is shown how options on forward variance swaps, along with options on the underlying can be priced consistently. The calibration of the model is done step-wise, first...

An Accelerated Testing Approach for Automated Vehicles with Background Traffic Described by Joint Distributions

OpenAIRE

Huang, Zhiyuan; Lam, Henry; Zhao, Ding

2017-01-01

This paper proposes a new framework based on joint statistical models for evaluating risks of automated vehicles in a naturalistic driving environment. The previous studies on the Accelerated Evaluation for automated vehicles are extended from multi-independent-variate models to joint statistics. The proposed toolkit includes exploration of the rare event (e.g. crash) sets and construction of accelerated distributions for Gaussian Mixture models using Importance Sampling techniques. Furthermo...

Peyton’s four-step approach: differential effects of single instructional steps on procedural and memory performance – a clarification study

Directory of Open Access Journals (Sweden)

Krautter M

2015-05-01

free recall test. Conclusion: Our study identified Peyton’s Step 3 as being the most crucial part within Peyton’s four-step approach, contributing significantly more to learning success than the previous steps and reaching beyond the benefit of a mere repetition of skills demonstration. Keywords: Peyton’s four-step approach, skills-lab training, procedural skills 

Vibrotactile stimulation of fast-adapting cutaneous afferents from the foot modulates proprioception at the ankle joint.

Science.gov (United States)

Mildren, Robyn L; Bent, Leah R

2016-04-15

It has previously been shown that cutaneous sensory input from across a broad region of skin can influence proprioception at joints of the hand. The present experiment tested whether cutaneous input from different skin regions across the foot can influence proprioception at the ankle joint. The ability to passively match ankle joint position (17° and 7° plantar flexion and 7° dorsiflexion) was measured while cutaneous vibration was applied to the sole (heel, distal metatarsals) or dorsum of the target foot. Vibration was applied at two different frequencies to preferentially activate Meissner's corpuscles (45 Hz, 80 μm) or Pacinian corpuscles (255 Hz, 10 μm) at amplitudes ∼3 dB above mean perceptual thresholds. Results indicated that cutaneous input from all skin regions across the foot could influence joint-matching error and variability, although the strongest effects were observed with heel vibration. Furthermore, the influence of cutaneous input from each region was modulated by joint angle; in general, vibration had a limited effect on matching in dorsiflexion compared with matching in plantar flexion. Unlike previous results in the upper limb, we found no evidence that Pacinian input exerted a stronger influence on proprioception compared with Meissner input. Findings from this study suggest that fast-adapting cutaneous input from the foot modulates proprioception at the ankle joint in a passive joint-matching task. These results indicate that there is interplay between tactile and proprioceptive signals originating from the foot and ankle. Copyright © 2016 the American Physiological Society.

Single-step link of the superdeformed band in 143Eu

International Nuclear Information System (INIS)

Atac, A.; Bergstroem, M.H.; Nyberg, J.; Persson, J.; Herskind, B.; Joss, D.T.; Lipoglavsek, M.; Tucek, K.

1996-01-01

A discrete γ-ray ransition with an energy of 3360.6 keV deexciting the second lowest SD state in 143 Eu has been discovered. It carries 3.2 % of the full intensity of the band and feeds into a nearly spherical state which is above the I = 35/2 (+) , E x =4947 keV level. The exact placement of the single-step link is, however, not established due to the specially complicated level scheme in the region of interest. The energy of the single-step link agrees well with the previously determined two-step links. (orig.)

The Treatment of Joint Pain with Intra-articular Pulsed Radiofrequency.

Science.gov (United States)

Schianchi, Pietro M; Sluijter, Menno E; Balogh, Susan E

2013-09-01

The intra-articular (IA) application of pulsed radiofrequency (PRF) for pain in small and large joints represents a recent development that has proven to be effective in many cases. We performed a retrospective study of 89 such procedures in 57 consecutive patients with chronic articular pain. The aim of this retrospective study is to evaluate the effectiveness of intraarticular PRF in a group of 57 consecutive patients with chronic joint pain. Patients with intractable joint pain for more than 6 months were treated with IA PRF 40-45V for 10-15 min in small joints and 60V for 15 min in large joints using fluoroscopic confirmation of correct needle position. A total of 28 shoulders, 40 knees, 10 trapezio-metacarpal, and 11 first metatarso-phalangeal joints were treated. Results were evaluated at 1, 2, and 5 months. The procedure was repeated after 1 month in 10 patients with initial suboptimal results. Success was defined as a reduction of pain score by at least 50%. All groups showed significant reductions in pain scores at all three follow-up visits. Success rates were higher in small joints (90% and 82%, respectively) than large ones (64% and 60%, respectively). Interestingly, IA PRF was successful in 6 out of 10 patients who had undergone previous surgery, including 3 with prosthetic joint replacement and in 6 of the 10 repeated procedures. There were no significant adverse effects or complications. IA PRF induced significant pain relief of long duration in a majority of our patients with joint pain. The exact mechanism is unclear, but may be related to the exposure of immune cells to low-strength RF fields, inducing an anti-inflammatory effect. The success rate appears to be highest in small joints. We recommend additional research including control groups to further investigate and clarify this method; our data suggest that it may represent a useful modality in the treatment of arthrogenic pain.

Joint Convention on the safety of spent fuel management and on the safety of radioactive waste management. France's answers to questions and comments received from other Contracting Parties on its second report for the JC

International Nuclear Information System (INIS)

2009-01-01

The Joint Convention on the Safety of Spent Fuel Management and the Safety of Radioactive Waste Management, referred to as the 'Joint Convention', is the result of international discussions that followed the adoption of the Convention on Nuclear Safety, in 1994. France signed the Joint Convention at the General Conference of the International Atomic Energy Agency (IAEA) held on 29 September 1997, the very first day the Joint Convention was opened for signature. She approved it on 22 February 2000 and filed the corresponding instruments with the IAEA on 27 April 2000. The Joint Convention entered into force on 18 June 2001. For many years, France has been taking an active part in the pursuit of international actions to reinforce nuclear safety and considers the Joint Convention to be a key step in that direction. The fields covered by the Joint Convention have long been part of the French approach to nuclear safety. For his second report, France presented a document reflecting the viewpoints of the various stakeholders (regulatory authorities and operators). Thus, for each of the chapters in which the regulatory authority is not the only party to express its point of view, a three-stage structure was adopted: first of all a description by the regulatory authority of the regulations, followed by a presentation by the operators of the steps taken to meet the regulations and finally, an analysis by the regulatory authority of the steps taken by the operators. France received questions and comments from the other contracting parties of the joint convention and answered them in the present document

Fluoroscopy-Guided Sacroiliac Intraarticular Injection via the Middle Portion of the Joint.

Science.gov (United States)

Kurosawa, Daisuke; Murakami, Eiichi; Aizawa, Toshimi

2017-09-01

Sacroiliac intraarticular injection is necessary to confirm sacroiliac joint (SIJ) pain and is usually performed via the caudal one-third portion of the joint. However, this is occasionally impossible for anatomical reasons, and the success rate is low in clinical settings. We describe a technique via the middle portion of the joint. Observational study. Enrolled were 69 consecutive patients (27 men and 42 women, with an average age of 53 years) in whom the middle portion of 100 joints was targeted. With the patient lying prone-oblique with the painful side down, a spinal needle was inserted into the middle portion of the joint. Subsequently, the fluoroscopy tube was angled at a caudal tilt of 25-30° to clearly detect the recess between the ilium and sacrum and the needle depth and direction. When the needle reached the posterior joint line, 2% lidocaine was injected after the contrast medium outlined the joint. The success rate of the injection method was 80% (80/100). Among 80 successful cases, four were previously unsuccessful when the conventional method was used. Intraarticular injection using the new technique was unsuccessful in 20 joints; in three of these cases, the conventional method proved successful, and no techniques were successful in the other 17 cases. The injection technique via the middle portion of the joint can overcome some of the difficulties of the conventional injection method and can improve the chances of successful intraarticular injection. © 2016 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Dynamic 3D FE modelling of the human temporomandibular joint during whiplash.

Science.gov (United States)

Pérez del Palomar, A; Doblaré, M

2008-07-01

Rear-end impacts account for more than one-third of vehicle accidents, and nearly 40% of these accidents produce whiplash injuries. Whiplash injury to the neck has often been considered a significant risk factor for the development of temporomandibular disorders (TMD). The objective of this study was to simulate the dynamic response of the temporomandibular joint during two types of impacts: a rear end and a frontal impact. To understand the dynamic forces acting on the joint, we extended a previous human temporomandibular joint model and analyzed the stress distributions in the soft elements of the joint. In the rear-end impact, it could be appreciated that the inertia of the mandible caused it to move posteriorly slower than the head, and this resulted in downward and forward displacements of the disc-condyle complex relative to the cranial base. Consequently, a rapid and big mouth opening occurs. In contrast, during the frontal impact, the mouth hardly opened, because the superior maxilla pushed the mandible to move together. There was not differential movement between bony components of the joint and therefore the soft tissues of the joint were not subjected to high loads. From these results, and despite the limitations of the simulations performed, we could conclude that neither a rear-end impact at low-velocity nor a frontal impact would produce damage to the soft tissues of the joint.

The stepping behavior analysis of pedestrians from different age groups via a single-file experiment

Science.gov (United States)

Cao, Shuchao; Zhang, Jun; Song, Weiguo; Shi, Chang'an; Zhang, Ruifang

2018-03-01

The stepping behavior of pedestrians with different age compositions in single-file experiment is investigated in this paper. The relation between step length, step width and stepping time are analyzed by using the step measurement method based on the calculation of curvature of the trajectory. The relations of velocity-step width, velocity-step length and velocity-stepping time for different age groups are discussed and compared with previous studies. Finally effects of pedestrian gender and height on stepping laws and fundamental diagrams are analyzed. The study is helpful for understanding pedestrian dynamics of movement. Meanwhile, it offers experimental data to develop a microscopic model of pedestrian movement by considering stepping behavior.

Three-dimensional versus two-dimensional sonography of the temporomandibular joint in comparison to MRI

Energy Technology Data Exchange (ETDEWEB)

Landes, Constantin A. [Oral, Maxillofacial and Plastic Facial Surgery, Frankfurt University Medical Centre, Theodor-Stern-Kai 7, 60596 Frankfurt (Germany)]. E-mail: c.landes@lycos.com; Goral, Wojciech A. [Oral, Maxillofacial and Plastic Facial Surgery, Frankfurt University Medical Centre, Theodor-Stern-Kai 7, 60596 Frankfurt (Germany)]. E-mail: w.goral@gmx.de; Sader, Robert [Oral, Maxillofacial and Plastic Facial Surgery, Frankfurt University Medical Centre, Theodor-Stern-Kai 7, 60596 Frankfurt (Germany)]. E-mail: r.sader@em.uni-frankfurt.de; Mack, Martin G. [Department of Diagnostic and Interventional Radiology, Frankfurt University Medical Centre, Theodor-Stern-Kai 7, 60596 Frankfurt (Germany)]. E-mail: martinmack@arcor.de

2007-02-15

Aim: To compare clinical feasibility of static two-dimensional (2D) to three-dimensional (3D) sonography of the temporomandibular joint (TMJ) in assessment of disk dislocation and joint degeneration compared to magnetic resonance imaging (MRI). Method: Thirty-three patients, 66 TMJ were prospectively sonographed 2D and 3D (8-12.5 MHz step motor scan), in occlusion and maximum opening with a probe position parallel inferior to the zygomatic arch. Axial 2D images were judged independent from the 3D scans; 3D volumes were cut axial, sagittal, frontal and rotated in real-time. Disk position and joint degeneration were assessed and compared to a subsequent MRI examination. Results: The specific appearance of the disk was hypoechogenic overlying a hyperechogenic condyle in axial (2D) or sagittal and frontal (3D) viewing. Specificity of 2D sonography for disk dislocation was 63%, sensitivity 58%, accuracy 64%, positive predictive value 46%, negative predictive value 73%; for joint degeneration synonymously 59/68/61/38/83%. 3D sonography for disk displacement reached synonymously 68/60/69/51/76%, for joint degeneration 75/65/73/48/86%. 2D sonographic diagnoses of disk dislocation in the closed mouth position and of joint degeneration showed significantly different results from the expected values (MRI) in {chi} {sup 2} testing; 3D diagnoses of disk dislocation in closed mouth position, of joint degeneration, 2D and 3D diagnoses in open mouth position were nonsignificant. Conclusions: Acceptable was the overall negative predictive value, as specificity and accuracy for joint degeneration in 3D. 3D appears superior diagnosing disk dislocation in closed mouth position as for overall joint degeneration. Sensitivity, accuracy and positive predictive value will have to ameliorate with future equipment of higher resolution in real-time 2D and 3D, if sonographic screening shall be clinically applied prior to MRI.

Stepping strategies for regulating gait adaptability and stability.

Science.gov (United States)

Hak, Laura; Houdijk, Han; Steenbrink, Frans; Mert, Agali; van der Wurff, Peter; Beek, Peter J; van Dieën, Jaap H

2013-03-15

Besides a stable gait pattern, gait in daily life requires the capability to adapt this pattern in response to environmental conditions. The purpose of this study was to elucidate the anticipatory strategies used by able-bodied people to attain an adaptive gait pattern, and how these strategies interact with strategies used to maintain gait stability. Ten healthy subjects walked in a Computer Assisted Rehabilitation ENvironment (CAREN). To provoke an adaptive gait pattern, subjects had to hit virtual targets, with markers guided by their knees, while walking on a self-paced treadmill. The effects of walking with and without this task on walking speed, step length, step frequency, step width and the margins of stability (MoS) were assessed. Furthermore, these trials were performed with and without additional continuous ML platform translations. When an adaptive gait pattern was required, subjects decreased step length (padaptations resulted in the preservation of equal MoS between trials, despite the disturbing influence of the gait adaptability task. When the gait adaptability task was combined with the balance perturbation subjects further decreased step length, as evidenced by a significant interaction between both manipulations (p=0.012). In conclusion, able-bodied people reduce step length and increase step width during walking conditions requiring a high level of both stability and adaptability. Although an increase in step frequency has previously been found to enhance stability, a faster movement, which would coincide with a higher step frequency, hampers accuracy and may consequently limit gait adaptability. Copyright © 2012 Elsevier Ltd. All rights reserved.

Does generalized joint hypermobility predict joint injury in sport? A review.

LENUS (Irish Health Repository)

Donaldson, Peter R

2012-02-01

OBJECTIVE: To determine whether persons with generalized joint hypermobility have an increased risk of lower limb joint injury during sport. DATA SOURCES: PubMed, CINAHL, EMBASE, and SportDiscus were searched through February 2009, without language restrictions, using terms related to risk; hip, ankle, and knee injuries; and joint instability. Reference lists of included studies and relevant reviews were searched by hand. STUDY SELECTION: Selection criteria were peer-reviewed studies with a prospective design that used an objective scale to measure generalized joint hypermobility; the participants were engaged in sport activity, and the injury data were quantitative and based on diagnosis by a health professional, were self-reported, or resulted in time lost to athletic participation. The studies were screened by 1 researcher and checked by a second. Study methods were independently assessed by 2 investigators using the 6-point scale for prognostic studies developed by Pengel. Disagreements were resolved through discussion. Of 4841 studies identified, 18 met inclusion criteria. Of these, 8 were included in random-effects meta-analyses. DATA EXTRACTION: The data extracted by 2 reviewers included participant and sport characteristics and details of joint hypermobility and injury measurements. More detailed data for 4 investigations were obtained from the study authors. Where possible, hypermobility was defined as >\\/=4 of 9 points on the British Society of Rheumatology Scale (BSRS). MAIN RESULTS: Lower limb joint injuries (3 studies, 1047 participants) occurred in 14% of participants. Using the BSRS of joint hypermobility, any lower limb injury was not associated with hypermobility [odds ratio (OR), 1.43; 95% confidence interval (CI), 0.56-3.67]. Using the original authors\\' definitions, hypermobility was associated with risk of knee joint injuries (OR, 2.62; 95% CI, 1.04-6.58) in 5 studies. In 4 studies in which the BSRS could be used (1167 participants; incidence

Zinc hexacyanoferrate film as an effective protecting layer in two-step and one-step electropolymerization of pyrrole on zinc substrate

Energy Technology Data Exchange (ETDEWEB)

Pournaghi-Azar, M.H. [Electroanalytical Chemistry Laboratory, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)]. E-mail: pournaghiazar@tabrizu.ac.ir; Nahalparvari, H. [Electroanalytical Chemistry Laboratory, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)

2005-03-15

The two-step and one-step electrosynthesis processes of polypyrrole (PPy) films on the zinc substrate are described. The two-step process includes (i) the zinc surface pretreatment with hexacyanoferrate ion in the aqueous medium in order to form a zinc hexacyanoferrate (ZnHCF) film non-blocking passive layer on the surface and with the view to prevent its reactivity and (ii) electropolymerization of pyrrole on the ZnHCF vertical bar Zn-modified electrode in aqueous pyrrole solution. In this context, both the non-electrolytic and electrolytic procedures were adapted, and the effect of some experimental conditions such as supporting electrolyte, pH and temperature of the solution at the zinc surface pretreatment step as well as pyrrole concentration and electrochemical techniques at the polymerization step was investigated. By optimizing the experimental conditions in both steps, we have obtained a homogeneous and strongly adherent PPy films on the zinc substrate. The one-step process is based on the use of an aqueous medium containing Fe(CN){sub 6}{sup 4-} and pyrrole. The ferrocyanide ion passivates the substrate by formation of ZnHCF film during the electropolymerization process of pyrrole and therefore makes it possible to obtain strongly adherent PPy films, with controlled thickness, either by cyclic voltammetry or by electrolysis at constant current or constant potential without any previously treatment of the zinc electrode surface. The polypyrrole films deposited on the zinc electrode were characterized by cyclic voltammetry and scanning electron microscopic (SEM) measurement.

Zinc hexacyanoferrate film as an effective protecting layer in two-step and one-step electropolymerization of pyrrole on zinc substrate

International Nuclear Information System (INIS)

Pournaghi-Azar, M.H.; Nahalparvari, H.

2005-01-01

The two-step and one-step electrosynthesis processes of polypyrrole (PPy) films on the zinc substrate are described. The two-step process includes (i) the zinc surface pretreatment with hexacyanoferrate ion in the aqueous medium in order to form a zinc hexacyanoferrate (ZnHCF) film non-blocking passive layer on the surface and with the view to prevent its reactivity and (ii) electropolymerization of pyrrole on the ZnHCF vertical bar Zn-modified electrode in aqueous pyrrole solution. In this context, both the non-electrolytic and electrolytic procedures were adapted, and the effect of some experimental conditions such as supporting electrolyte, pH and temperature of the solution at the zinc surface pretreatment step as well as pyrrole concentration and electrochemical techniques at the polymerization step was investigated. By optimizing the experimental conditions in both steps, we have obtained a homogeneous and strongly adherent PPy films on the zinc substrate. The one-step process is based on the use of an aqueous medium containing Fe(CN) 6 4- and pyrrole. The ferrocyanide ion passivates the substrate by formation of ZnHCF film during the electropolymerization process of pyrrole and therefore makes it possible to obtain strongly adherent PPy films, with controlled thickness, either by cyclic voltammetry or by electrolysis at constant current or constant potential without any previously treatment of the zinc electrode surface. The polypyrrole films deposited on the zinc electrode were characterized by cyclic voltammetry and scanning electron microscopic (SEM) measurement

A computational model for three-dimensional jointed media with a single joint set

International Nuclear Information System (INIS)

Koteras, J.R.

1994-02-01

This report describes a three-dimensional model for jointed rock or other media with a single set of joints. The joint set consists of evenly spaced joint planes. The normal joint response is nonlinear elastic and is based on a rational polynomial. Joint shear stress is treated as being linear elastic in the shear stress versus slip displacement before attaining a critical stress level governed by a Mohr-Coulomb faction criterion. The three-dimensional model represents an extension of a two-dimensional, multi-joint model that has been in use for several years. Although most of the concepts in the two-dimensional model translate in a straightforward manner to three dimensions, the concept of slip on the joint planes becomes more complex in three dimensions. While slip in two dimensions can be treated as a scalar quantity, it must be treated as a vector in the joint plane in three dimensions. For the three-dimensional model proposed here, the slip direction is assumed to be the direction of maximum principal strain in the joint plane. Five test problems are presented to verify the correctness of the computational implementation of the model

Pseudoaneurysm of the facial artery following bilateral temporomandibular joint replacement: A case report

Directory of Open Access Journals (Sweden)

Lanit Anand

2017-03-01

Case report: A 59-year-old male presented to our department with bony ankylosis of his temporomandibular joints bilaterally as a result of previous osteomyelitis. He underwent bilateral temperomandibular joint replacements in a two-stage procedure. Six weeks post discharge he presented to the emergency department in haemorrhagic shock, having lost significant blood volume from a pulsatile lesion over his right mandible. Computed tomography angiography revealed a pseudoaneurysm of the right facial artery. He proceeded to emergent embolisation with resolution of the pseudoaneurysm.

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

Science.gov (United States)

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.

[Efficacy analysis on hip replacement for hip-joint diseases with Parkinson disease].

Science.gov (United States)

Sun, Qi-Cai; Ru, Xuan-Liang; Xia, Yan-Fei; Liu, Xiao-Li; Song, Bai-Shan; Qiao, Song; Yan, Shi-Gui; Wang, Xiang-Hua

2017-12-25

To explore clinical efficacy of hip replacement for hip-joint diseases with Parkinson disease. From December 2011 to December 2016, 18 patients with hip-joint diseases with Parkinson disease treated by hip replacement, including 8 males and 10 females aged from 59 to 87 years old with an average of 71 years old. Among them, 3 cases were developmental dysplasia of hip, 3 cases were femoral head necrosis and 12 cases were femoral neck fracture. All patients manifested with obvious pain and limitation of stepping ability. Postoperative complications were observed and Harris score were used to compare hip joint function after operation. The incision were healed well, and pain were alleviated or disappeared, and hip joint function were improved. Eighteen patients were followed up from 1 to 3 years with an average of 2.3 years. At the latest follow up, 14 cases recovered freedom-walk, 2 cases could walk with walking stick, 1 case could walk with walking aid and 1 case was died. Among 18 patients, 2 cases were occurred dislocation, and 1 case were died for cardiac disease at 3 months after operation. Four patients were occurred slight pain. There were significant differences in Harris scores among preoperative (41.7±1.4), 6 months after operation(80.1±5.4) and the final follow-up (83.4±2.1), and 10 cases got excellent result, 4 good, 1 fair and 2 poor. Application of hip replacement for hip-joint diseases with Parkinson disease is a safe and effective clinical therapy, and has advantages of less complications and rapid recovery of hip joint function.

Joint ventures

DEFF Research Database (Denmark)

Sørensen, Karsten Engsig

Afhandlingen analysere de konkurrenceretlige og selskabsretlige regler som er bestemmende for hvordan et joint venture samarbejde er struktureret......Afhandlingen analysere de konkurrenceretlige og selskabsretlige regler som er bestemmende for hvordan et joint venture samarbejde er struktureret...

Analytical Time-Domain Solution of Plane Wave Propagation Across a Viscoelastic Rock Joint

Science.gov (United States)

Zou, Yang; Li, Jianchun; Laloui, Lyesse; Zhao, Jian

2017-10-01

The effects of viscoelastic filled rock joints on wave propagation are of great significance in rock engineering. The solutions in time domain for plane longitudinal ( P-) and transverse ( S-) waves propagation across a viscoelastic rock joint are derived based on Maxwell and Kelvin models which are, respectively, applied to describe the viscoelastic deformational behaviour of the rock joint and incorporated into the displacement discontinuity model (DDM). The proposed solutions are verified by comparing with the previous studies on harmonic waves, which are simulated by sinusoidal incident P- and S-waves. Comparison between the predicted transmitted waves and the experimental data for P-wave propagation across a joint filled with clay is conducted. The Maxwell is found to be more appropriate to describe the filled joint. The parametric studies show that wave propagation is affected by many factors, such as the stiffness and the viscosity of joints, the incident angle and the duration of incident waves. Furthermore, the dependences of the transmission and reflection coefficients on the specific joint stiffness and viscosity are different for the joints with Maxwell and Kelvin behaviours. The alternation of the reflected and transmitted waveforms is discussed, and the application scope of this study is demonstrated by an illustration of the effects of the joint thickness. The solutions are also extended for multiple parallel joints with the virtual wave source method and the time-domain recursive method. For an incident wave with arbitrary waveform, it is convenient to adopt the present approach to directly calculate wave propagation across a viscoelastic rock joint without additional mathematical methods such as the Fourier and inverse Fourier transforms.

CHANGES IN PATELLOFEMORAL JOINT STRESS DURING RUNNING WITH THE APPLICATION OF A PREFABRICATED FOOT ORTHOTIC.

Science.gov (United States)

Almonroeder, Thomas G; Benson, Lauren C; O'Connor, Kristian M

2015-12-01

Foot orthotics are commonly utilized in the treatment of patellofemoral pain (PFP) and have shown clinical benefit; however, their mechanism of action remains unclear. Patellofemoral joint stress (PFJS) is thought to be one of the main etiological factors associated with PFP. The primary purpose of this study was to investigate the effects of a prefabricated foot orthotic with 5 ° of medial rearfoot wedging on the magnitude and the timing of the peak PFJS in a group of healthy female recreational athletes. The hypothesis was that there would be significant reduction in the peak patellofemoral joint stress and a delay in the timing of this peak in the orthotic condition. Cross-sectional. Kinematic and kinetic data were collected during running trials in a group of healthy, female recreational athletes. The knee angle and moment data in the sagittal plane were incorporated into a previously developed model to estimate patellofemoral joint stress. The dependent variables of interest were the peak patellofemoral joint stress as well as the percentage of stance at which this peak occurred, as both the magnitude and the timing of the joint loading are thought to be important in overuse running injuries. The peak patellofemoral joint stress significantly increased in the orthotic condition by 5.8% (p=.02, ES=0.24), which does not support the initial hypothesis. However, the orthotic did significantly delay the timing of the peak during the stance phase by 3.8% (p=.002, ES=0.47). The finding that the peak patellofemoral joint stress increased in the orthotic condition did not support the initial hypothesis. However, the finding that the timing of this peak was delayed to later in the stance phase in the orthotic condition did support the initial hypothesis and may be related to the clinical improvements previously reported in subjects with PFP. Level 4.

Thermomechanical repository and shaft response analyses using the CAVS [Cracking And Void Strain] jointed rock model: Draft final report

International Nuclear Information System (INIS)

Dial, B.W.; Maxwell, D.E.

1986-12-01

Numerical studies of the far-field repository and near-field shaft response for a nuclear waste repository in bedded salt have been performed with the STEALTH computer code using the CAVS model for jointed rock. CAVS is a constitutive model that can simulate the slip and dilatancy of fracture planes in a jointed rock mass. The initiation and/or propagation of fractures can also be modeled when stress intensity criteria are met. The CAVS models are based on the joint models proposed with appropriate modifications for numerical simulations. The STEALTH/CAVS model has been previously used to model (1) explosive fracturing of a wellbore, (2) earthquake effects on tunnels in a generic nuclear waste repository, (3) horizontal emplacement for a nuclear waste repository in jointed granite, and (4) tunnel response in jointed rock. The use of CAVS to model far-field repository and near-field shaft response was different from previous approaches because it represented a spatially oriented approach to rock response and failure, rather than the traditional stress invariant formulation for yielding. In addition, CAVS tracked the response of the joint apertures to the time-dependent stress changes in the far-field repository and near-field shaft regions. 28 refs., 21 figs., 11 tabs

A New Method for Determination of Joint Roughness Coefficient of Rock Joints

Directory of Open Access Journals (Sweden)

Shigui Du

2015-01-01

Full Text Available The joint roughness coefficient (JRC of rock joints has the characteristic of scale effect. JRC measured on small-size exposed rock joints should be evaluated by JRC scale effect in order to obtain the JRC of actual-scale rock joints, since field rock joints are hardly fully exposed or well saved. Based on the validity analysis of JRC scale effect, concepts of rate of JRC scale effect and effective length of JRC scale effect were proposed. Then, a graphic method for determination of the effective length of JRC scale effect was established. Study results show that the JRC of actual-scale rock joints can be obtained through a fractal model of JRC scale effect according to the statistically measured results of the JRC of small-size partial exposed rock joints and by the selection of fractal dimension of JRC scale effect and the determination of effective length of JRC scale effect.

Biplanar x-ray fluoroscopy for sacroiliac joint fusion.

Science.gov (United States)

Vanaclocha-Vanaclocha, Vicente; Verdú-López, Francisco; Sáiz-Sapena, Nieves; Herrera, Juan Manuel; Rivera-Paz, Marlon

2016-07-01

Chronic pain originating from the sacroiliac joint (SI) can cause severe dysfunction. Although many patients respond to conservative management with NSAIDs, some do need further treatment in the form of SI joint fusion (SIJF). To achieve safe and successful SIJF, intraoperative x-ray fluoroscopy is mandatory to avoid serious damages to nearby vascular and neural structures. Each step of the procedure has to be confirmed by anteroposterior (AP) and lateral projections. With a single-arm x-ray, the arch has to be moved back and forth for the AP and lateral projections, and this lengthens the procedure. To achieve the same results in less time, the authors introduced simultaneous biplanar fluoroscopy with 2 x-ray arches. After the patient is positioned prone with the legs spread apart in the so-called Da Vinci position, one x-ray arch for the lateral projection is placed at a right angle to the patient, and a second x-ray machine is placed with its arch between the legs of the patient. This allows simultaneous AP and lateral x-ray projections and, in the authors' hands, markedly speeds up the procedure. Biplanar fluoroscopy allows excellent AP and lateral projections to be made quickly at any time during the surgical procedure. This is particularly useful in cases of bilateral SI joint fusion if both sides are done at the same time. The video can be found here: https://youtu.be/TX5gz8c765M .

3rd Joint Dutch-Brazil School on Theoretical Physics

CERN Document Server

2015-01-01

The Joint Dutch-Brazil School on Theoretical Physics is now in its third edition with previous schools in 2007 and 2011. This edition of the school will feature minicourses by Nima Arkani-Hamed (IAS Princeton), Jan de Boer (University of Amsterdam) and Cumrun Vafa (Harvard University), as well as student presentations. The school is jointly organized with the Dutch Research School of Theoretical Physics (DRSTP) and is intended for graduate students and researchers in the field of high-energy theoretical physics. There is no registration fee and limited funds are available for local and travel support of participants. This school in São Paulo will be preceded by the XVIII J. A. Swieca School in Campos de Jordão.

Reductions in knee joint forces with weight loss are attenuated by gait adaptations in class III obesity

NARCIS (Netherlands)

DeVita, Paul; Rider, Patrick; Hortobagyi, Tibor

A consensus exists that high knee joint forces are a precursor to knee osteoarthritis and weight loss reduces these forces. Because large weight loss also leads to increased step length and walking velocity, knee contact forces may be reduced less than predicted by the magnitude of weight loss. The

Degradation of Epoxy-Steel Single Lap Joints Immersed in Water

DEFF Research Database (Denmark)

Goglio, L; Rezaei, Mohsen

2015-01-01

Exposure to environmental factors, especially moisture, is recognized as the major cause of degradation of adhesive joints. In this work, complementing a previous study on exposure to moisture, single lap joints were subjected to immersion in water, up to five weeks, at room temperature and 50 °C....... The material of the adherends was mild steel, and the adhesive was a bi-component epoxy. The specimens were fabricated using the open-face technique. Mechanical testing at the end of the relevant period of immersion showed an initial loss of ultimate load, after one week at 50 °C or two at room temperature......; then, the strength remained practically constant over the remaining time. The loss was more accentuated after immersion at 50 °C, about 70%, than at room temperature, about 30%. Also a reduction in stiffness of the joints was measured, again dramatic (about 70%) after immersion at 50 °C, moderate...

Thermally Conductive Metal-Tube/Carbon-Composite Joints

Science.gov (United States)

Copeland, Robert J.

2004-01-01

An improved method of fabricating joints between metal and carbon-fiber-based composite materials in lightweight radiators and heat sinks has been devised. Carbon-fiber-based composite materials have been used in such heat-transfer devices because they offer a combination of high thermal conductivity and low mass density. Metal tubes are typically used to carry heat-transfer fluids to and from such heat-transfer devices. The present fabrication method helps to ensure that the joints between the metal tubes and the composite-material parts in such heat-transfer devices have both (1) the relatively high thermal conductances needed for efficient transfer of heat and (2) the flexibility needed to accommodate differences among thermal expansions of dissimilar materials in operation over wide temperature ranges. Techniques used previously to join metal tubes with carbon-fiber-based composite parts have included press fitting and bonding with epoxy. Both of these prior techniques have been found to yield joints characterized by relatively high thermal resistances. The present method involves the use of a solder (63 percent Sn, 37 percent Pb) to form a highly thermally conductive joint between a metal tube and a carbon-fiber-based composite structure. Ordinarily, the large differences among the coefficients of thermal expansion of the metal tube, solder, and carbon-fiber-based composite would cause the solder to pull away from the composite upon post-fabrication cooldown from the molten state. In the present method, the structure of the solder is modified (see figure) to enable it to deform readily to accommodate the differential thermal expansion.

Reading Aloud: Does Previous Trial History Modulate the Joint Effects of Stimulus Quality and Word Frequency?

Science.gov (United States)

O'Malley, Shannon; Besner, Derek

2013-01-01

No one would argue with the proposition that how we process events in the world is strongly affected by our experience. Nonetheless, recent experience (e.g., from the previous trial) is typically not considered in the analysis of timed cognitive performance in the laboratory. Masson and Kliegl (2013) reported that, in the context of the lexical…

Effect of process parameters on microstructure and mechanical properties of friction stir welded joints: A review

Science.gov (United States)

Wanare, S. P.; Kalyankar, V. D.

2018-04-01

Friction stir welding is emerging as a promising technique for joining of lighter metal alloys due to its several advantages over conventional fusion welding processes such as low thermal distortion, good mechanical properties, fine weld joint microstructure, etc. This review article mainly focuses on analysis of microstructure and mechanical properties of friction stir welded joints. Various microstructure characterization techniques used by previous researchers such as optical microscopes, x-ray diffraction, electron probe microscope, transmission electron microscope, scanning electron microscopes with electron back scattered diffraction, electron dispersive microscopy, etc. are thoroughly overviewed and their results are discussed. The effects of friction stir welding process parameters such as tool rotational speed, welding speed, tool plunge depth, axial force, tool shoulder diameter to tool pin diameter ratio, tool geometry etc. on microstructure and mechanical properties of welded joints are studied and critical observations are noted down. The microstructure examination carried out by previous researchers on various zones of welded joints such as weld zone, heat affected zone and base metal are studied and critical remarks have been presented. Mechanical performances of friction stir welded joints based on tensile test, micro-hardness test, etc. are discussed. This article includes exhaustive literature review of standard research articles which may become ready information for subsequent researchers to establish their line of action.

Wide field of view CT and acromioclavicular joint instability: A technical innovation.

Science.gov (United States)

Dyer, David R; Troupis, John M; Kamali Moaveni, Afshin

2015-06-01

A 21-year-old female with a traumatic shoulder injury is investigated and managed for symptoms relating to this injury. Pathology at the acromioclavicular joint is detected clinically; however, clinical examination and multiple imaging modalities do not reach a unified diagnosis on the grading of this acromioclavicular joint injury. When management appropriate to that suggested injury grading fail to help the patient's symptoms, further investigation methods were utilised. Wide field of view, dynamic CT (4D CT) is conducted on the patient's affected shoulder using a 320 × 0.5 mm detector multislice CT. Scans were conducted with a static table as the patient completed three movements of the affected shoulder. Capturing multiple data sets per second over a z-axis of 16 cm, measurements of the acromioclavicular joint were made, to show dynamic changes at the joint. Acromioclavicular (AC) joint translations were witnessed in three planes (a previously unrecognised pathology in the grading of acromioclavicular joint injuries). Translation in multiple planes was also not evident on careful clinical examination of this patient. AC joint width, anterior-posterior translation, superior-inferior translation and coracoclavicular width were measured with planar reconstructions while volume-rendered images and dynamic sequences aiding visual understanding of the pathology. Wide field of view dynamic CT (4D CT) is an accurate and quick modality to diagnose complex acromioclavicular joint injury. It provides dynamic information that no other modality can; 4D CT shows future benefits for clinical approach to diagnosis and management of acromioclavicular joint injury, and other musculoskeletal pathologies. © 2015 The Royal Australian and New Zealand College of Radiologists.

Validation of surface crack stress intensity factors of a tubular K-joint

International Nuclear Information System (INIS)

Lie, S.T.; Lee, C.K.; Chiew, S.P.; Shao, Y.B.

2005-01-01

Tubular K-joints are encountered widely in offshore structures, and the prediction of damaged joints depends very much on the accuracy of stress intensity factor solutions (SIFs). No parametric equations and very few results have been proposed and published in the literature for estimating the SIFs of any K-joints subjected to complex loading conditions. In this paper, a mesh generation method proposed previously for the Y-joint and T-joint has been extended to the K-joint. This method is realized by dividing the K-joint into several sub-zones with each zone consisting of different types of elements and mesh densities. This method has a distinct advantage of controlling the mesh quality, and most importantly the aspect ratio of the elements along the crack front. When the mesh of all the sub-zones has been generated automatically and completely, they are merged to form the complete model. The two most commonly used methods, namely the J-integral and displacement extrapolation, are used to evaluate the SIF values along the crack front of a typical K-joint. To validate the accuracy of these computed SIFs, a full-scale K-joint specimen was tested to failure under fatigue loading conditions. The standard alternating current potential drop (ACPD) technique was used to monitor the rate of crack propagation of the surface crack located at the hot spot stress region. Using the given material parameters C and m, the experimental SIFs were deduced, and they are found to be in good agreement with the computed SIFs obtained from the generated models. Hence, the proposed finite element models are both efficient and reliable

Laboratory characterization of rock joints

International Nuclear Information System (INIS)

Hsiung, S.M.; Kana, D.D.; Ahola, M.P.; Chowdhury, A.H.; Ghosh, A.

1994-05-01

A laboratory characterization of the Apache Leap tuff joints under cyclic pseudostatic and dynamic loads has been undertaken to obtain a better understanding of dynamic joint shear behavior and to generate a complete data set that can be used for validation of existing rock-joint models. Study has indicated that available methods for determining joint roughness coefficient (JRC) significantly underestimate the roughness coefficient of the Apache Leap tuff joints, that will lead to an underestimation of the joint shear strength. The results of the direct shear tests have indicated that both under cyclic pseudostatic and dynamic loadings the joint resistance upon reverse shearing is smaller than that of forward shearing and the joint dilation resulting from forward shearing recovers during reverse shearing. Within the range of variation of shearing velocity used in these tests, the shearing velocity effect on rock-joint behavior seems to be minor, and no noticeable effect on the peak joint shear strength and the joint shear strength for the reverse shearing is observed

THE RELATIONSHIP BETWEEN TEMPOROMANDIBULAR-JOINT MOBILITY AND PERIPHERAL JOINT MOBILITY RECONSIDERED

NARCIS (Netherlands)

Dijkstra, P.U.; DEBONT, L.G.M.; VANDERWEELE, L.T.; Boering, G.

The purpose of this paper was to study the relationship between temporomandibular joint (TMJ) mobility and mobility of joints and to study the general character of joint mobility in 83 subjects, 55 females and 28 males (mean age 26.7, range 13-46 years). The subjects were recruited from the

Dual joint space arthrography in temporomandibular joint disorders: Comparison with single inferior joint space arthrography

Energy Technology Data Exchange (ETDEWEB)

Choi, Hyung Sik; Chang, Duk Soo; Lee, Kyung Soo; Kim, Woo Sun; Sung, Jung Ho; Jun, Young Hwan [Capital Armed Forces General Hospital, Seoul (Korea, Republic of)

1989-02-15

The temporomandibular joint(TMJ) is really a complex of two synovial space separated by fibrocartilaginous disc. Single inferior joint space arthrography is commonly performed for evaluation of TMJ disorders, which is known to be superior in demonstrating joint dynamics. But it reveals only the inferior surface of the disc. Therefore, dual space arthrography is superior to demonstrate the soft tissue anatomic feature of the joint such as disc position and shape. Authors performed 83 TMJ arthrograms in TMJ problems. Initially, the inferior joint space was done and then the superior space was sequentially contrasted. The follow results were noted: 1. In all cases, dual space arthrography revealed accurate disc shape and positions. 2. Concordant findings between the two techniques: 68 cases (82%). Discordance between the two techniques: 15 cases (18%) 3. Possible causes of discordance between inferior and dual space arthrography. a) Normal varians of anterior recess: 3 cases b) Posterior disc displacement: 4 cases c) Influence of the patient's head position change :4 cases d) False perforation: 2 cases e) Reduction change: 2 cases 4. In 5 cases with anterior displacement, dual space arthrography gave additional findings such as adhesion within the superior space, which could not be evaluated by single inferior space.

In vitro method for assessing the biomechanics of the patellofemoral joint following total knee arthroplasty.

Science.gov (United States)

Coles, L G; Gheduzzi, S; Miles, A W

2014-12-01

The patellofemoral joint is a common site of pain and failure following total knee arthroplasty. A contributory factor may be adverse patellofemoral biomechanics. Cadaveric investigations are commonly used to assess the biomechanics of the joint, but are associated with high inter-specimen variability and often cannot be carried out at physiological levels of loading. This study aimed to evaluate the suitability of a novel knee simulator for investigating patellofemoral joint biomechanics. This simulator specifically facilitated the extended assessment of patellofemoral joint biomechanics under physiological levels of loading. The simulator allowed the knee to move in 6 degrees of freedom under quadriceps actuation and included a simulation of the action of the hamstrings. Prostheses were implanted on synthetic bones and key soft tissues were modelled with a synthetic analogue. In order to evaluate the physiological relevance and repeatability of the simulator, measurements were made of the quadriceps force and the force, contact area and pressure within the patellofemoral joint using load cells, pressure-sensitive film, and a flexible pressure sensor. The results were in agreement with those previously reported in the literature, confirming that the simulator is able to provide a realistic physiological loading situation. Under physiological loading, average standard deviations of force and area measurements were substantially lower and comparable to those reported in previous cadaveric studies, respectively. The simulator replicates the physiological environment and has been demonstrated to allow the initial investigation of factors affecting patellofemoral biomechanics following total knee arthroplasty. © IMechE 2014.

Joint Electromagnetic Spectrum Management Operations

Science.gov (United States)

2012-03-20

promulgate command-specific policy and guidance for EMS use, the joint restricted frequency list (JRFL) process, the joint communications–electronics...joint communications–electronics operating instructions (JCEOI) and joint restricted frequency list (JRFL). Examples of FM include providing the...joint restricted frequency list Figure III-4. Joint Frequency Management Office Spectrum Management Process Chapter III III-10 JP 6-01 assignments

Efficacy, Beliefs, and Investment in Step-Level Public Goods

NARCIS (Netherlands)

Dijkstra, Jacob; Mulders, Jaap Oude

2014-01-01

A central concept for understanding social dilemma behavior is the efficacy of an actor's cooperative behavior in terms of increasing group well-being. We report a decision and game theoretical analysis of efficacy in step-level public goods (SPGs). Previous research shows a positive relation

Common path in-line holography using enhanced joint object reference digital interferometers

OpenAIRE

Kelner, Roy; Katz, Barak; Rosen, Joseph

2014-01-01

Joint object reference digital interferometer (JORDI) is a recently developed system capable of recording holograms of various types [Opt. Lett. 22(5), 4719 (2013)]. Presented here is a new enhanced system design that is based on the previous JORDI. While the previous JORDI has been based purely on diffractive optical elements, displayed on spatial light modulators, the present design incorporates an additional refractive objective lens, thus enabling hologram recording with improved resoluti...

Joint diseases

International Nuclear Information System (INIS)

Weissman, S.D.

1989-01-01

The authors discuss how x-ray examination is essential in the diagnosis and evaluation of the arthritides. Most arthritides are first suspected by the clinician, and x-ray evaluation of these entities along with laboratory testing is important for confirmation of the clinical diagnosis and in staging of the disease process. Several arthritides are often diagnosed first by the podiatrist on x-ray evaluation, including pseudogout, ankylosing spondylitis, early rheumatoid arthritis, degenerative joint disease, and tuberculosis of bone. The joint responds to insult in only a limited number of ways that become apparent on x-ray. The soft tissues surrounding the joint, the articulating bones, and alignment of the joint space may all be involved by the arthritic process. On roentgenographic examination, the soft tissues must be examined for edema, masses, calcifications, and atrophy. The articulating bones must be examined for demineralization, erosions, osteophytes, periosteal reaction, cysts and sclerosis

Experience of the implementation of quality management system at the joint stock company 'Mashinostroitelny zavod', Electrostal

International Nuclear Information System (INIS)

Mezhuev, V.; Tsiboulia, V.; Kiruyshkin, A.; Tchirkov, V.

2000-01-01

The paper describes major steps of development and implementation of Quality Management System (QMS) in nuclear fuel fabrication at Joint Stock Company 'Mashinostroitelny zavod', Electrostal, Russian Federation. Special emphasis is paid to the estimation of QMS effectiveness, current impact of QMS implementation on nuclear fuel quality, sales market and directions for further QMS development. (author)

Biomechanical and neuromuscular adaptations during the landing phase of a stepping-down task in patients with early or established knee osteoarthritis

NARCIS (Netherlands)

Sanchez-Ramirez, Diana C.; Malfait, Bart; Baert, Isabel; van der Leeden, Marike; van Dieën, Jaap; Lems, Willem F.; Dekker, Joost; Luyten, Frank P.; Verschueren, Sabine

Background: To compare the knee joint kinematics, kinetics and EMG activity patterns during a stepping-down task in patients with knee osteoarthritis (OA) with control subjects. Methods: 33 women with knee OA (early OA, n = 14; established OA n = 19) and 14 female control subjects performed a

Imaging findings of charcot joint

International Nuclear Information System (INIS)

Meng Quanfei; Zhou Chunxiang; Chen Yingming; Jiang Bo

2003-01-01

Objective: To analyze the MRI characters of Charcot joint, and to evaluate the diagnostic value of X-ray, CT, and MRI on Charcot joint. Methods: Eight patients with 8 Charcot joints underwent X-ray, CT, and MR examinations. 6 of them had syringomyelia, 1 patient had injury of the spinal cord, and 1 case had diabetes. All 8 patients had sensory reduction or deficit in the sick extremities. Results: There were two types of Charcot joint, hypertrophic and atrophic. Radiographic and CT features of hypertrophic joint (n=3) showed hyperostotic osteosclerosis and mammoth osteophytes in the sick bones, periarticular ossification, and articular disorganization. Radiographic and CT features of atrophic joint (n=5) showed extensive bone resorption (destruction), periarticular debris, and articular disorganization. Main MRI features of Charcot joint included hydrarthrosis within joint capsule, thickened, loose, and elongated joint capsule with para-joint, peri-diaphysis, and inter-muscular extension in a pseudopodia pattern. The irregular joint capsule wall was presented as mild hypointensity on T 1 WI, slight hyper-intensity on T 2 WI, and was markedly enhanced after Gd-DTPA was administrated, which was considered as a characteristic manifestation of the lesion. Soft tissue mass containing hypo-intense stripes on both T 1 WI and T 2 WI was commonly noted adjacent to the involved joint. Conclusion: X-rays plain film is the first choice for the diagnosis of Charcot joint, and MRI is pretty useful in the diagnosis of Charcot joint

Radiographic and magnetic resonance imaging of the stifle joint in experimental osteoarthritis of dogs

International Nuclear Information System (INIS)

Widmer, W.R.; Buckwalter, K.A.; Braunstein, E.M.; Hill, M.A.; O'Connor, B.L.; Visco, D.M.

1994-01-01

Radiography and magnetic resonance imaging were used to evaluate osteoarthritis at 2, 6, and 12 weeks following transection of the cranial cruciate ligament of the stifle (femorotibial) joint of 6 dogs. A quantitative radiographic scoring system was used to assess the progression of hard and soft tissue changes of osteoarthritis. Mediolateral (flexed joint) and oblique (extended joint) radiographic projections enabled identification of small osteophytes on the femoral trochlear ridges, which were detected at an earlier stage of development than was previously reported. Magnetic resonance imaging was useful in detecting changes in cartilage thickness, osteophytosis and intraarticular loose bodies. Radiography and magnetic resonance imaging were complementary in the assessment of pathologic changes of osteoarthritis

Posterior treatment of delayed traumatic atlantoaxial joint dislocation with apofix internal fixation

International Nuclear Information System (INIS)

Qing Wei; Jiang Weimin; Shi Jinhui; Li Xuefeng; Yang Huilin; Tang Tiansi

2010-01-01

Objective: To assess the effect of posterior fixation and fusion with Apofix device for the treatment of delayed traumatic atlantoaxial joint dislocation. Methods: Eighteen patients with delayed traumatic atlantoaxial joint dislocation were included. Posterior fixation and fusion with Apofix device were performed. First step was one or two week skull traction. After the atlantoaxial joint dislocation had been reduced, the posterior fixation and fusion with Apofix was performed. Using local anaesthesia, atlantoaxial interval and posterior structure of atlas and dentata were exposed by midline operative approach. Apofix interlaminar clamps were placed at posterior arch of atlas and odontoid vertebral laminae, autologous iliac bone graft was placed for fusion. Then the device to proper position was pressurized and items locked. Results: All of the patients were followed up, the mean follow-up period was 38 months (13 ∼ 84 months). Fifteen patients obtained complete reduction, the others were partial reduction. Seventeen patients had successful fusion after 3 or 4 months, only 1 patient who had partial reduction had internal fixation loose and nonfusion, leading to recurrence of atlantoaxial joint dislocation. An occipitocervical fusion surgery was performed on this patient. As to neurological assessment, 16 patients had neurological deficit before operation, while 6 of them recovered completely after operation, another 10 patients' neurological status improved significantly. JOA score was improved from 9.5 pre-operative to 15.8 post-operative. Conclusion: Apofix internal fixation and fusion seems to be feasible in treatment of delayed traumatic atlantoaxial joint dislocation. Successful reduction before operation and proper treatment after operation is also important. (authors)

T2 Mapping of Articular Cartilage of Glenohumeral Joint with Routine MRI Correlation—Initial Experience

OpenAIRE

Maizlin, Zeev V.; Clement, Jason J.; Patola, Wayne B.; Fenton, David M.; Gillies, Jean H.; Vos, Patrick M.; Jacobson, Jon A.

2009-01-01

The evaluation of articular cartilage currently relies primarily on the identification of morphological alterations of the articular cartilage. Unlike anatomic imaging, T2 mapping is sensitive to changes in the chemical composition and structure of the cartilage. Clinical evaluation of T2 mapping of the glenohumeral joint has not been previously reported. The objectives of this study were to evaluate the feasibility of magnetic resonance T2 mapping of the glenohumeral joint in routine clinica...

Pakistan stepping up expansion of refining, transportation sectors

International Nuclear Information System (INIS)

Anon.

1992-01-01

This paper reports that Pakistan is taking steps to speed expansion of its refining and oil transportation infrastructure. While the country has made significant progress toward energy self-efficiency by boosting oil and gas production it still must modernize and expand an aging, inadequate refining sector to meet rapidly growing demand for refined products. Pakistan's government has disclosed plans to build two refineries in the country, one at Rawalpindi near a string of recent oil discoveries, the other somewhere in the southern part of the country, likely Karachi. At the same time, efforts are proceeding to upgrade Pakistan's refineries. In addition, Pakistani state companies continue to press joint ventures in refining and marketing with foreign companies and expand downstream ties with neighbors that are key oil and gas exporters

Image-Guided Surgical Robotic System for Percutaneous Reduction of Joint Fractures.

Science.gov (United States)

Dagnino, Giulio; Georgilas, Ioannis; Morad, Samir; Gibbons, Peter; Tarassoli, Payam; Atkins, Roger; Dogramadzi, Sanja

2017-11-01

Complex joint fractures often require an open surgical procedure, which is associated with extensive soft tissue damages and longer hospitalization and rehabilitation time. Percutaneous techniques can potentially mitigate these risks but their application to joint fractures is limited by the current sub-optimal 2D intra-operative imaging (fluoroscopy) and by the high forces involved in the fragment manipulation (due to the presence of soft tissue, e.g., muscles) which might result in fracture malreduction. Integration of robotic assistance and 3D image guidance can potentially overcome these issues. The authors propose an image-guided surgical robotic system for the percutaneous treatment of knee joint fractures, i.e., the robot-assisted fracture surgery (RAFS) system. It allows simultaneous manipulation of two bone fragments, safer robot-bone fixation system, and a traction performing robotic manipulator. This system has led to a novel clinical workflow and has been tested both in laboratory and in clinically relevant cadaveric trials. The RAFS system was tested on 9 cadaver specimens and was able to reduce 7 out of 9 distal femur fractures (T- and Y-shape 33-C1) with acceptable accuracy (≈1 mm, ≈5°), demonstrating its applicability to fix knee joint fractures. This study paved the way to develop novel technologies for percutaneous treatment of complex fractures including hip, ankle, and shoulder, thus representing a step toward minimally-invasive fracture surgeries.

Sacroiliac Joint Fusion Minimally Affects Adjacent Lumbar Segment Motion: A Finite Element Study.

Science.gov (United States)

Lindsey, Derek P; Kiapour, Ali; Yerby, Scott A; Goel, Vijay K

2015-01-01

Adjacent segment disease is a recognized consequence of fusion in the spinal column. Fusion of the sacroiliac joint is an effective method of pain reduction. Although effective, the consequences of sacroiliac joint fusion and the potential for adjacent segment disease for the adjacent lumbar spinal levels is unknown. The objective of this study was to quantify the change in range of motion of the sacroiliac joint and the adjacent lumbar spinal motion segments due to sacroiliac joint fusion and compare these changes to previous literature to assess the potential for adjacent segment disease in the lumbar spine. An experimentally validated finite element model of the lumbar spine and pelvis was used to simulate a fusion of the sacroiliac joint using three laterally placed triangular implants (iFuse Implant System, SI-BONE, Inc., San Jose, CA). The range of motion of the sacroiliac joint and the adjacent lumbar spinal motion segments were calculated using a hybrid loading protocol and compared with the intact range of motion in flexion, extension, lateral bending, and axial rotation. The range of motions of the treated sacroiliac joints were reduced in flexion, extension, lateral bending, and axial rotation, by 56.6%, 59.5%, 27.8%, and 53.3%, respectively when compared with the intact condition. The stiffening of the sacroiliac joint resulted in increases at the adjacent lumbar motion segment (L5-S1) for flexion, extension, lateral bending, and axial rotation, of 3.0%, 3.7%, 1.1%, and 4.6%, respectively. Fusion of the sacroiliac joint resulted in substantial (> 50%) reductions in flexion, extension, and axial rotation of the sacroiliac joint with minimal (sacroiliac joint fusion, the long-term clinical results remain to be investigated.

Joint Symbol Timing and CFO Estimation for OFDM/OQAM Systems in Multipath Channels

Directory of Open Access Journals (Sweden)

Petrella Angelo

2010-01-01

Full Text Available The problem of data-aided synchronization for orthogonal frequency division multiplexing (OFDM systems based on offset quadrature amplitude modulation (OQAM in multipath channels is considered. In particular, the joint maximum-likelihood (ML estimator for carrier-frequency offset (CFO, amplitudes, phases, and delays, exploiting a short known preamble, is derived. The ML estimators for phases and amplitudes are in closed form. Moreover, under the assumption that the CFO is sufficiently small, a closed form approximate ML (AML CFO estimator is obtained. By exploiting the obtained closed form solutions a cost function whose peaks provide an estimate of the delays is derived. In particular, the symbol timing (i.e., the delay of the first multipath component is obtained by considering the smallest estimated delay. The performance of the proposed joint AML estimator is assessed via computer simulations and compared with that achieved by the joint AML estimator designed for AWGN channel and that achieved by a previously derived joint estimator for OFDM systems.

The value of HEAD-US system in detecting subclinical abnormalities in joints of patients with hemophilia.

Science.gov (United States)

De la Corte-Rodriguez, Hortensia; Rodriguez-Merchan, E Carlos; Alvarez-Roman, M Teresa; Martin-Salces, Mónica; Martinoli, Carlo; Jimenez-Yuste, Víctor

2018-03-01

Prevention of hemarthrosis is the key factor in the adequate management of people with hemophilia (PWH). If hemarthrosis occurs, early diagnosis of joint damage is essential to make personalized treatments. This study is aimed at gaining an understanding of the ability of point-of-care ultrasound (US) using the `Hemophilia Early Arthropathy Detection with Ultrasound´ (HEAD-US) protocol to detect abnormalities in joints without history of hemarthrosis and clinically asymptomatic joints of PWH. The sample included 976 joints from 167 PWH (mean age 24.86 years). Data were collected from routine practice over a 3-year period and analyzed based on history of hemarthrosis and results of clinical (HJHS 2.1) and HEAD-US examinations. In our series, 14% of patients exhibited HEAD-US signs of incipient arthropathy in joints with no history of bleeding and with a HJHS 2.1 score of 0. The most severely involved joint was the right ankle. Synovitis, articular cartilage and subchondral bone damage scores in joints with subclinical findings were slower than in joints with previous hemarthroses or HJHS 2.1 > 1 Conclusions: Our study demonstrates that HEAD-US is better than hemarthrosis records and the HJHS 2.1 scale in detecting the early signs of joint damage in PWH.

Efficacy, Beliefs, and Investment in Step-Level Public Goods

NARCIS (Netherlands)

Dijkstra, J.; Oude Mulders, J.

2014-01-01

behavior in terms of increasing group well-being. We report a decision and game theoretical analysis of efficacy in step-level public goods (SPGs). Previous research shows a positive relation between efficacy and contributions to SPGs and explains this relation by a purely motivational account. We

Leakage flow-induced vibrations for variations of a tube-in-tube slip joint

International Nuclear Information System (INIS)

Mulcahy, T.M.

1986-01-01

Variations in the design of a specific slip joint separating two cantilevered, telescoping tubes conveying water were studied to determine their effect upon the leakage flow-induced vibration self-excitation mechanism known to exist for the original slip joint geometry. The important parameters controlling the self-excitation mechanism were identified, which, along with previous results, allowed the determination of a comprehensive set of design rules to avoid unstable vibrations. This was possible even though a new self-excitation mechanism was found when the engagement of the two tubes was small. 9 refs

Partial safety factor calibration from stochastic finite element computation of welded joint with random geometries

International Nuclear Information System (INIS)

Schoefs, Franck; Chevreuil, Mathilde; Pasqualini, Olivier; Cazuguel, Mikaël

2016-01-01

Welded joints are used in various structures and infrastructures like bridges, ships and offshore structures, and are submitted to cyclic stresses. Their fatigue behaviour is an industrial key issue to deal with and still offers original research subjects. One of the available methods relies on the computing of the stress concentration factor. Even if some studies were previously driven to evaluate this factor onto some cases of welded structures, the shape of the weld joint is generally idealized through a deterministic parametric geometry. Previous experimental works however have shown that this shape plays a key role in the lifetime assessment. We propose in this paper a methodology for computing the stress concentration factor in presence of random geometries of welded joints. In view to make the results available by engineers, this method merges stochastic computation and semi-probabilistic analysis by computing partial safety factors with a dedicated method. - Highlights: • Numerical computation of stress concentration factor with random geometry of weld. • Real data are used for probabilistic modelling. • Identification of partial safety factor from SFEM computation in case of random geometries.

METHODS USED FOR THE VIRTUAL HUMAN BONES AND JOINTS RECONSTRUCTION. NORMAL AND PATHOLOGICAL HUMAN JOINTS VIRTUAL SIMULATIONS

Directory of Open Access Journals (Sweden)

POPA Laurentiu Dragos

2015-06-01

Full Text Available To understand the problems, which appear in every human joint, it is very important to know the anatomy and morphology of the human bones and the way in which the components are working together to realize a normal functionality. For this purpose was used a CAD parametric software which permits to define models with a high degree of difficulty. First, it was used a CT or MRI device to obtain the parallel sections to study each component of the bone. A 3D scanner can be used only for the outer geometry. In the second step the images were transferred to a 2D CAD software, like AutoCAD, where the outer and inner contours of the bone were approximate to polygonal lines composed by many segments. After this, the contours were transferred to a 3D CAD software, like SolidWorks, where, step by step, and section by section, was defined the virtual bone component. Additionally to the main shape can be attached other Loft, Round or Dome shapes. For some components, as vertebrae, mandible or skull bones, can be used a preliminary model obtained by parallel sections. Starting from this, the model can be defined using the main 3D curves and we can get the final virtual solid model. In some simulations, the soft components, as muscles or ligaments, were included in simulations using non-linear virtual springs. Also, sometimes were used implants or prosthetic elements. In the final of the paper, were extracted important conclusions.

Low Level Laser Therapy for chronic knee joint pain patients.

Science.gov (United States)

Nakamura, Takashi; Ebihara, Satoru; Ohkuni, Ikuko; Izukura, Hideaki; Harada, Takashi; Ushigome, Nobuyuki; Ohshiro, Toshio; Musha, Yoshiro; Takahashi, Hiroshi; Tsuchiya, Kazuaki; Kubota, Ayako

2014-12-27

Chronic knee joint pain is one of the most frequent complaints which is seen in the outpatient clinic in our medical institute. In previous studies we have reported the benefits of low level laser therapy (LLLT) for chronic pain in the shoulder joints, elbow, hand, finger and the lower back. The present study is a report on the effects of LLLT for chronic knee joint pain. Over the past 5 years, 35 subjects visited the outpatient clinic with complaints of chronic knee joint pain caused by the knee osteoarthritis-induced degenerative meniscal tear. They received low level laser therapy. A 1000 mW semi-conductor laser device was used to deliver 20.1 J/cm(2) per point in continuous wave at 830nm, and four points were irradiated per session (1 treatment) twice a week for 4 weeks. A visual analogue scale (VAS) was used to determine the effects of LLLT for the chronic pain and after the end of the treatment regimen a significant improvement was observed (pknee joint range of motion. Discussions with the patients revealed that it was important for them to learn how to avoid postures that would cause them knee pain in everyday life in order to have continuous benefits from the treatment. The present study demonstrated that 830 nm LLLT was an effective form of treatment for chronic knee pain caused by knee osteoarthritis. Patients were advised to undertake training involving gentle flexion and extension of the knee.

A new algorithm for three-dimensional joint inversion of body wave and surface wave data and its application to the Southern California plate boundary region

Science.gov (United States)

Fang, Hongjian; Zhang, Haijiang; Yao, Huajian; Allam, Amir; Zigone, Dimitri; Ben-Zion, Yehuda; Thurber, Clifford; van der Hilst, Robert D.

2016-05-01

We introduce a new algorithm for joint inversion of body wave and surface wave data to get better 3-D P wave (Vp) and S wave (Vs) velocity models by taking advantage of the complementary strengths of each data set. Our joint inversion algorithm uses a one-step inversion of surface wave traveltime measurements at different periods for 3-D Vs and Vp models without constructing the intermediate phase or group velocity maps. This allows a more straightforward modeling of surface wave traveltime data with the body wave arrival times. We take into consideration the sensitivity of surface wave data with respect to Vp in addition to its large sensitivity to Vs, which means both models are constrained by two different data types. The method is applied to determine 3-D crustal Vp and Vs models using body wave and Rayleigh wave data in the Southern California plate boundary region, which has previously been studied with both double-difference tomography method using body wave arrival times and ambient noise tomography method with Rayleigh and Love wave group velocity dispersion measurements. Our approach creates self-consistent and unique models with no prominent gaps, with Rayleigh wave data resolving shallow and large-scale features and body wave data constraining relatively deeper structures where their ray coverage is good. The velocity model from the joint inversion is consistent with local geological structures and produces better fits to observed seismic waveforms than the current Southern California Earthquake Center (SCEC) model.

Shoulder joint loading and posture during medicine cart pushing task.

Science.gov (United States)

Xu, Xu; Lin, Jia-Hua; Boyer, Jon

2013-01-01

Excessive physical loads and awkward shoulder postures during pushing and pulling are risk factors for shoulder pain. Pushing a medicine cart is a major component of a work shift for nurses and medical assistants in hospitals and other health care facilities. A laboratory experiment was conducted to examine the effects of common factors (e.g., lane congestion, cart load stability, floor surface friction) on shoulder joint moment and shoulder elevation angle of participants during cart pushing. Participants pushed a medicine cart on straight tracks and turning around right-angle corners. Peak shoulder joint moments reached 25.1 Nm, 20.3 Nm, and 26.8 Nm for initial, transition, and turning phases of the pushing tasks, indicating that shoulder joint loading while pushing a medical cart is comparable to levels previously reported from heavy manual activities encountered in industry (e.g., garbage collection). Also, except for user experience, all other main study factors, including congestion level, cart load stability, location of transition strip, shoulder tendency, surface friction, and handedness, significantly influenced shoulder joint moment and shoulder elevation angle. The findings provide a better understanding of shoulder exposures associated with medicine cart operations and may be helpful in designing and optimizing the physical environment where medicine carts are used.

One Mission-Centered, Market-Smart Globalization Response: A Case Study of the Georgia Tech-Emory University Biomedical Engineering Curricular Joint Venture

Science.gov (United States)

Burriss, Annie Hunt

2010-01-01

One innovative, higher-education response to globalization and changing fiscal realities is the curricular joint venture (CJV), a formal collaboration between academic institutions that leverages missions through new joint degrees and research not previously offered by collaborating institutions (Eckel, 2003). In 1997, a pioneering biomedical…

Joint crisis plans and psychiatric advance directives in German psychiatric practice.

Science.gov (United States)

Radenbach, Katrin; Falkai, Peter; Weber-Reich, Traudel; Simon, Alfred

2014-05-01

This study explores the attitude of German psychiatrists in leading positions towards joint crisis plans and psychiatric advance directives. This topic was examined by contacting 473 medical directors of German psychiatric hospitals and departments. They were asked to complete a questionnaire developed by us. That form contained questions about the incidence and acceptance of joint crisis plans and psychiatric advance directives and previous experiences with them. 108 medical directors of psychiatric hospitals and departments responded (response rate: 22.8%). Their answers demonstrate that in their hospitals these documents are rarely used. Among the respondents, joint crisis plans are more accepted than psychiatric advance directives. There is a certain uncertainty when dealing with these instruments. Our main conclusion is that German psychiatry needs an intensified discussion on the use of instruments for patients to constitute procedures for future critical psychiatric events. For this purpose it will be helpful to collect more empirical data. Furthermore, the proposal of joint crisis plans in psychiatric hospitals and departments should be discussed as well as the possibility of consulting an expert during the preparation of a psychiatric advance directive.

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

Science.gov (United States)

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.

Prosthesis of the wrist-joint

Energy Technology Data Exchange (ETDEWEB)

Feldmeier, C.

1983-02-25

Function of the hand-joint and the well-being of patients can be severely affected by arthrosis of the wrist-joint. Therapeutically, arthrodesis usually results in a painfree status of stiffness. A painless and well functioning joint can be achieved by alloplastic joint replacement or resurfacing. The possibilities and clinical results in cases of arthrosis of the carpo-metacarpal joint of the thumb, pseudarthrosis of the scaphoid, aseptic necrosis of the Lunate and severe arthrosis of the radio-carpal joint are demonstrated.

[Short-term effectiveness of Swanson artificial joint replacement in treating posttraumatic metacarpophalangeal joint stiffness].

Science.gov (United States)

Lu, Hui; Shen, Xiangqian; Xu, Jihua; Huang, Xin; Ye, Po; Wu, Shoucheng

2011-11-01

To investigate the short-term effectiveness of Swanson artificial joint replacement in treating post-traumatic metacarpophalangeal joint stiffness. Between August 2007 and May 2010, 11 cases (13 fingers) of metacarpophalangeal joint stiffness with soft tissue defects underwent Swanson artificial joint replacement. There were 7 males (9 fingers) and 4 females (4 fingers), aged 43 to 65 years with an average of 49 years. The involved fingers included 4 thumbs, 4 index fingers, 3 middle fingers, and 2 ring fingers. The types of injury included open and crush injury in 8 fingers, fracture of the metacarpophalangeal joint in 3 fingers, metacarpophalangeal joint severing in 2 fingers. The time from joint stiffness to hospitalization was 12 to 48 weeks (mean, 24 weeks). The joint activity was (136.82 +/- 28.96) degrees. According to total active motion (TAM) assessment, included good in 1 finger, fair in 6 fingers, and poor in 6 fingers before operation. The activities of daily living were assessed by Sollerman score, which was 45.64 +/- 11.04. The X-ray films and CT scan showed traumatic arthritis of the metacarpophalangeal joint. The incision healed by first intention. All patients were followed up 12 to 34 months (mean, 24.1 months). At last follow-up, the joint activity was (194.64 +/- 28.86) degrees, showing significant difference when compared with preoperative value (t = 25.214, P = 0.000). According to TAM assessment, including excellent in 1 finger, good in 4 fingers, fair in 7 fingers, and poor in 1 finger. The Sollerman score was 67.45 +/- 8.20 postoperatively, showing significant difference when compared with the preoperative score (t = -10.470, P = 0.000). X-ray examination showed no prosthesis fracture, periprosthetic fracture, or joint dislocation occurred at last follow-up. Swanson artificial joint replacement can be applied to treat post-traumatic metacarpophalangeal joint stiffness, which can improve the joint activity and has satisfactory short

SEALING LARGE-DIAMETER CAST-IRON PIPE JOINTS UNDER LIVE CONDITIONS

Energy Technology Data Exchange (ETDEWEB)

Kiran M. Kothari; Gerard T. Pittard

2005-04-01

Utilities in the U.S. operate over 75,000 km (47,000 miles) of old cast-iron pipes for gas distribution. The bell-and-spigot joints that connect pipe sections together tend to leak as these pipes age. Current repair practices are costly and highly disruptive. The objective of this program is to design, test and commercialize a robotic system capable of sealing multiple cast-iron bell and spigot joints from a single pipe entry point. The proposed system will perform repairs while the pipe remains in service by traveling through the pipe, cleaning each joint surface, and installing a stainless-steel sleeve lined with an epoxy-impregnated felt across the joint. This approach will save considerable time and labor, avoid traffic disruption, and eliminate any requirement to interrupt service to customers (which would result in enormous expense to utilities). Technical challenges include: (1) repair sleeves must compensate for diametric variation and eccentricity of old cast-iron pipes; (2) the assembly must travel long distances through pipes containing debris; (3) the pipe wall must be effectively cleaned in the immediate area of the joint to assure good bonding of the sleeve; and (4) an innovative bolt-on entry fitting is required to conduct repair operations on live mains. The development effort is divided into eleven tasks. Task 1 (Program Management) and Task 2 (Establishment of Detailed Design Specifications) were completed previously. Task 3 (Design and Fabricate Ratcheting Stainless-Steel Repair Sleeves) has progressed to installing prototype sleeves in test cast-iron pipe segments. Efforts in the current quarter continued to be focused on Tasks 4-8. Highly valuable lessons were learned from field tests of the 4-inch gas pipe repair robot in cast-iron pipe at Public Service Electric & Gas. (These field tests were conducted and reported previously.) Several design issues were identified which need to be implemented in both the small- and large-diameter repair

Step dynamics and terrace-width distribution on flame-annealed gold films: The effect of step-step interaction

International Nuclear Information System (INIS)

Shimoni, Nira; Ayal, Shai; Millo, Oded

2000-01-01

Dynamics of atomic steps and the terrace-width distribution within step bunches on flame-annealed gold films are studied using scanning tunneling microscopy. The distribution is narrower than commonly observed for vicinal planes and has a Gaussian shape, indicating a short-range repulsive interaction between the steps, with an apparently large interaction constant. The dynamics of the atomic steps, on the other hand, appear to be influenced, in addition to these short-range interactions, also by a longer-range attraction of steps towards step bunches. Both types of interactions promote self-ordering of terrace structures on the surface. When current is driven through the films a step-fingering instability sets in, reminiscent of the Bales-Zangwill instability

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

Directory of Open Access Journals (Sweden)

Evangelos I. Avgoulas

2016-07-01

Full Text Available 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.

Prosthesis of the wrist-joint

International Nuclear Information System (INIS)

Feldmeier, C.

1983-01-01

Function of the hand-joint and the well-being of patients can be severely affected by arthrosis of the wrist-joint. Therapeutically, arthrodesis usually results in a painfree status of stiffness. A painless and well functioning joint can be achieved by alloplastic joint replacement or resurfacing. The possibilities and clinical results in cases of arthrosis of the carpo-metacarpal joint of the thumb, pseudarthrosis of the scaphoid, aseptic necrosis of the Lunate and severe arthrosis of the radio-carpal joint are demonstrated. (orig.) [de

Traffic safety and step-by-step driving licence for young people

DEFF Research Database (Denmark)

Tønning, Charlotte; Agerholm, Niels

2017-01-01

presents a review of safety effects from step-by-step driving licence schemes. Most of the investigated schemes consist of a step-by-step driving licence with Step 1) various tests and education, Step 2) a period where driving is only allowed together with an experienced driver and Step 3) driving without...... companion is allowed but with various restrictions and, in some cases, additional driving education and tests. In general, a step-by-step driving licence improves traffic safety even though the young people are permitted to drive a car earlier on. The effects from driving with an experienced driver vary......Young novice car drivers are much more accident-prone than other drivers - up to 10 times that of their parents' generation. A central solution to improve the traffic safety for this group is implementation of a step-by-step driving licence. A number of countries have introduced a step...

Design of mechanical joints

CERN Document Server

Blake, Alexander

2018-01-01

A cornerstone publication that covers the basic principles and practical considerations of design methodology for joints held by rivets, bolts, weld seams, and adhesive materials, Design of Mechanical Joints gives engineers the practical results and formulas they need for the preliminary design of mechanical joints, combining the essential topics of joint mechanics...strength of materials...and fracture control to provide a complete treatment of problems pertinent to the field of mechanical connections.

Refining patterns of joint hypermobility, habitus, and orthopedic traits in joint hypermobility syndrome and Ehlers-Danlos syndrome, hypermobility type.

Science.gov (United States)

Morlino, Silvia; Dordoni, Chiara; Sperduti, Isabella; Venturini, Marina; Celletti, Claudia; Camerota, Filippo; Colombi, Marina; Castori, Marco

2017-04-01

Joint hypermobility syndrome (JHS) and Ehlers-Danlos syndrome, hypermobility type (EDS-HT) are two overlapping heritable disorders (JHS/EDS-HT) recognized by separated sets of diagnostic criteria and still lack a confirmatory test. This descriptive research was aimed at better characterizing the clinical phenotype of JHS/EDS-HT with focus on available diagnostic criteria, and in order to propose novel features and assessment strategies. One hundred and eighty-nine (163 females, 26 males; age: 2-73 years) patients from two Italian reference centers were investigated for Beighton score, range of motion in 21 additional joints, rate and sites of dislocations and sprains, recurrent soft-tissue injuries, tendon and muscle ruptures, body mass index, arm span/height ratio, wrist and thumb signs, and 12 additional orthopedic features. Rough rates were compared by age, sex, and handedness with a series of parametric and non-parametric tools. Multiple correspondence analysis was carried out for possible co-segregations of features. Beighton score and hypermobility at other joints were influenced by age at diagnosis. Rate and sites of joint instability complications did not vary according to age at diagnosis except for soft-tissue injuries. No major difference was registered by sex and dominant versus non-dominant body side. At multiple correspondence analysis, selected features tend to co-segregate in a dichotomous distribution. Dolichostenomelia and arachnodactyly segregated independently. This study pointed out a more protean musculoskeletal phenotype than previously considered according to available diagnostic criteria for JHS/EDS-HT. Our findings corroborated the need for a re-thinking of JHS/EDS-HT on clinical grounds in order to find better therapeutic and research strategies. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Part I. Remembering No. 2 (Ladislav Loerinc). EMO joint venture, joint-stock company - really completely useless organ?

International Nuclear Information System (INIS)

Blaha, M.

2008-01-01

In this chapter author reviewed the story of the EMO joint venture, joint-stock company, between Slovenske elektrarne, a. s. and EdF. EMO joint venture, joint-stock company, was established to complete the Mochovce nuclear power plant. EMO joint venture, joint-stock company was closed after one year of work. History of EMO joint venture, joint-stock company, was described by its former general manager Mr. Ladislav Loerinc.

Influence of serotonin on the analgesic effect of granisetron on temporomandibular joint arthritis

Directory of Open Access Journals (Sweden)

Ülle Voog

2004-01-01

Full Text Available THE influence of circulating serotonin (5-HT on the effects of intra-articular administration of granisetron on temporomandibular joint (TMJ pain was investigated in 11 patients with chronic polyarthritides. An analgesic effect superior to placebo has been shown previously.

Photoelastic investigation of the stresses in a stepped cylinder under internal pressure

International Nuclear Information System (INIS)

Sawa, Yoshiaki; Nishida, Masataka

1985-01-01

The states of stress distribution of the stepped cylinder under inner-pressure are studied by means of stress freezing photoelastic method. The experimental results reveal that fiber stress concentration occurs on the circular arc and hoop stress concentration occurs at the jointing point of the straight line and the arc and that each maximum value of fiver stress and hoop stress depends very greatly on the diameter of a small cylinder and the radius of curvature. And the relationship between the stress concentration factors and these shape factors are given. Effects of wall thickness on the stress concentration factors are also determined. (author)

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

Science.gov (United States)

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.

Forming a multinational joint venture

International Nuclear Information System (INIS)

Bhatia, N.K.; Garb, R.H.; Statton, T.D.

1990-01-01

This paper discusses the basis and mechanics for forming a multinational joint venture. The topics of the paper include the motivations for a joint venture, selection of the appropriate co-venturer, management of the multinational joint venture, and the joint venture agreement. The authors state that a joint venture is not applicable or desirable in all instances and to be successful, must be carefully planned

Joint imaging

International Nuclear Information System (INIS)

Hengst, W.

1984-01-01

Joint imaging is a proven diagnostic procedure which has become indispensable to the detection and treatment of different joint diseases in almost all disciplines. The method is suited for early diagnosis of joint affections both in soft tissue and bone which cannot be detected by X-ray or other procedures. The local activity accumulation depends on the rate of metabolism and is visualized in the scan, which in turn enables the extension and floridity of focal lesions to be evaluated and followed-up. Although joint scans may often give hints to probabilities relevant to differential diagnosis, the method is non-specific and only useful if based on the underlying clinical picture and X-ray finding, if possible. The radiation exposure is very low and does not represent a hazard in cases of adequate assessment of indication. In pregnant women and children the assessment of indication has to be based on very strict principles. The method is suited for out-patient diagnosis and can be applied in all installations equipped with a gamma camera and a technetium generator. (orig.) [de

Managing Joint Production Motivation

DEFF Research Database (Denmark)

Lindenberg, Siegwart; Foss, Nicolai Juul

2011-01-01

We contribute to the microfoundations of organizational performance by proffering the construct of joint production motivation. Under such motivational conditions individuals see themselves as part of a joint endeavor, each with his or her own roles and responsibilities; generate shared...... representations of actions and tasks; cognitively coordinate cooperation; and choose their own behaviors in terms of joint goals. Using goal-framing theory, we explain how motivation for joint production can be managed by cognitive/symbolic management and organizational design....

The Unexplored Role of Intra-articular Adipose Tissue in the Homeostasis and Pathology of Articular Joints

Directory of Open Access Journals (Sweden)

Luminita Labusca

2018-03-01

Full Text Available Intra-articular adipose tissue deposits known as articular fat pads (AFPs are described to exist within synovial joints. Their assumed role in normal joint biomechanics is increasingly objectivized by means of advanced methods of functional imaging. AFPs possess structural similarity with body subcutaneous white adipose tissue (WAT, however, seems to be regulated by independent metabolic loops. AFP dimension are conserved during extreme WAT states: obesity, metabolic syndrome, lipodystrophy, and cachexia. Hoffa fat pad (HFP in the knee is increasingly recognized as a major player in pathological joint states such as anterior knee pain and osteoarthritis. HFP contains numerous population of mesenchymal and endothelial progenitors; however, the possible role of mature adipocytes in the maintenance of stem cell niche is unknown. We propose that AFP is an active component of the joint organ with multifunctional roles in the maintenance of joint homeostasis. Endowed with a rich network of sensitive nervous fibbers, AFPs may act as a proprioceptive organ. Adipokines and growth factors released by AFP-resident mature adipocytes could participate in the maintenance of progenitor stem cell niche as well as in local immune regulation. AFP metabolism may be locally controlled, correlated with but independent of WAT homeostasis. The identification of AFP role in normal joint turnover and its possible implication in pathological states could deliver diagnostic and therapeutic targets. Drug and/or cell therapies that restore AFP structure and function could become the next step in the design of disease modifying therapies for disabling joint conditions such as osteoarthritis and inflammatory arthritis.

Mechanics of Suture Joints

Science.gov (United States)

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.

A step-defined sedentary lifestyle index: <5000 steps/day.

Science.gov (United States)

Tudor-Locke, Catrine; Craig, Cora L; Thyfault, John P; Spence, John C

2013-02-01

Step counting (using pedometers or accelerometers) is widely accepted by researchers, practitioners, and the general public. Given the mounting evidence of the link between low steps/day and time spent in sedentary behaviours, how few steps/day some populations actually perform, and the growing interest in the potentially deleterious effects of excessive sedentary behaviours on health, an emerging question is "How many steps/day are too few?" This review examines the utility, appropriateness, and limitations of using a reoccurring candidate for a step-defined sedentary lifestyle index: 10 000) to lower (sedentary lifestyle index for adults is appropriate for researchers and practitioners and for communicating with the general public. There is little evidence to advocate any specific value indicative of a step-defined sedentary lifestyle index in children and adolescents.

Design of a Two-Step Calibration Method of Kinematic Parameters for Serial Robots

Science.gov (United States)

WANG, Wei; WANG, Lei; YUN, Chao

2017-03-01

Serial robots are used to handle workpieces with large dimensions, and calibrating kinematic parameters is one of the most efficient ways to upgrade their accuracy. Many models are set up to investigate how many kinematic parameters can be identified to meet the minimal principle, but the base frame and the kinematic parameter are indistinctly calibrated in a one-step way. A two-step method of calibrating kinematic parameters is proposed to improve the accuracy of the robot's base frame and kinematic parameters. The forward kinematics described with respect to the measuring coordinate frame are established based on the product-of-exponential (POE) formula. In the first step the robot's base coordinate frame is calibrated by the unit quaternion form. The errors of both the robot's reference configuration and the base coordinate frame's pose are equivalently transformed to the zero-position errors of the robot's joints. The simplified model of the robot's positioning error is established in second-power explicit expressions. Then the identification model is finished by the least square method, requiring measuring position coordinates only. The complete subtasks of calibrating the robot's 39 kinematic parameters are finished in the second step. It's proved by a group of calibration experiments that by the proposed two-step calibration method the average absolute accuracy of industrial robots is updated to 0.23 mm. This paper presents that the robot's base frame should be calibrated before its kinematic parameters in order to upgrade its absolute positioning accuracy.

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

Science.gov (United States)

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.

Joint inversion of NMR and SIP data to estimate pore size distribution of geomaterials

Science.gov (United States)

Niu, Qifei; Zhang, Chi

2018-03-01

There are growing interests in using geophysical tools to characterize the microstructure of geomaterials because of the non-invasive nature and the applicability in field. In these applications, multiple types of geophysical data sets are usually processed separately, which may be inadequate to constrain the key feature of target variables. Therefore, simultaneous processing of multiple data sets could potentially improve the resolution. In this study, we propose a method to estimate pore size distribution by joint inversion of nuclear magnetic resonance (NMR) T2 relaxation and spectral induced polarization (SIP) spectra. The petrophysical relation between NMR T2 relaxation time and SIP relaxation time is incorporated in a nonlinear least squares problem formulation, which is solved using Gauss-Newton method. The joint inversion scheme is applied to a synthetic sample and a Berea sandstone sample. The jointly estimated pore size distributions are very close to the true model and results from other experimental method. Even when the knowledge of the petrophysical models of the sample is incomplete, the joint inversion can still capture the main features of the pore size distribution of the samples, including the general shape and relative peak positions of the distribution curves. It is also found from the numerical example that the surface relaxivity of the sample could be extracted with the joint inversion of NMR and SIP data if the diffusion coefficient of the ions in the electrical double layer is known. Comparing to individual inversions, the joint inversion could improve the resolution of the estimated pore size distribution because of the addition of extra data sets. The proposed approach might constitute a first step towards a comprehensive joint inversion that can extract the full pore geometry information of a geomaterial from NMR and SIP data.

The independent effects of speed and propulsive force on joint power generation in walking.

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Browne, Michael G; Franz, Jason R

2017-04-11

Walking speed is modulated using propulsive forces (F P ) during push-off and both preferred speed and F P decrease with aging. However, even prior to walking slower, reduced F P may be accompanied by potentially unfavorable changes in joint power generation. For example, compared to young adults, older adults exhibit a redistribution of mechanical power generation from the propulsive plantarflexor muscles to more proximal muscles acting across the knee and hip. Here, we used visual biofeedback based on real-time F P measurements to decouple and investigate the interaction between joint-level coordination, whole-body F P , and walking speed. 12 healthy young subjects walked on a dual-belt instrumented treadmill at a range of speeds (0.9-1.3m/s). We immediately calculated the average F P from each speed. Subjects then walked at 1.3m/s while completing a series of biofeedback trials with instructions to match their instantaneous F P to their averaged F P from slower speeds. Walking slower decreased F P and total positive joint work with little effect on relative joint-level contributions. Conversely, subjects walked at a constant speed with reduced F P , not by reducing total positive joint work, but by redistributing the mechanical demands of each step from the plantarflexor muscles during push-off to more proximal leg muscles during single support. Interestingly, these naturally emergent joint- and limb-level biomechanical changes, in the absence of neuromuscular constraints, resemble those due to aging. Our findings provide important reference data to understand the presumably complex interactions between joint power generation, whole-body F P , and walking speed in our aging population. Copyright © 2017 Elsevier Ltd. All rights reserved.

Joint Intentionality

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Koreň Ladislav

2016-03-01

Full Text Available According to the shared intentionality hypothesis proposed by Michael Tomasello, two cognitive upgrades – joint and collective intentionality, respectively – make human thinking unique. Joint intentionality, in particular, is a mindset supposed to account for our early, species-specific capacity to participate in collaborative activities involving two (or a few agents. In order to elucidate such activities and their proximate cognitive-motivational mechanism, Tomasello draws on philosophical accounts of shared intentionality. I argue that his deference to such cognitively demanding accounts of shared intentional activities is problematic if his theoretical ambition is in part to show that and how early (prelinguistic and precultural capacities for joint action contribute to the development of higher cognitive capacities.

Quantifying the influence of previously burned areas on suppression effectiveness and avoided exposure: A case study of the Las Conchas Fire

Science.gov (United States)

Matthew P. Thompson; Patrick Freeborn; Jon D. Rieck; Dave Calkin; Julie W. Gilbertson-Day; Mark A. Cochrane; Michael S. Hand

2016-01-01

We present a case study of the Las Conchas Fire (2011) to explore the role of previously burned areas (wildfires and prescribed fires) on suppression effectiveness and avoided exposure. Methodological innovations include characterisation of the joint dynamics of fire growth and suppression activities, development of a fire line effectiveness framework, and...

Upper ankle joint space detection on low contrast intraoperative fluoroscopic C-arm projections

Science.gov (United States)

Thomas, Sarina; Schnetzke, Marc; Brehler, Michael; Swartman, Benedict; Vetter, Sven; Franke, Jochen; Grützner, Paul A.; Meinzer, Hans-Peter; Nolden, Marco

2017-03-01

Intraoperative mobile C-arm fluoroscopy is widely used for interventional verification in trauma surgery, high flexibility combined with low cost being the main advantages of the method. However, the lack of global device-to- patient orientation is challenging, when comparing the acquired data to other intrapatient datasets. In upper ankle joint fracture reduction accompanied with an unstable syndesmosis, a comparison to the unfractured contralateral site is helpful for verification of the reduction result. To reduce dose and operation time, our approach aims at the comparison of single projections of the unfractured ankle with volumetric images of the reduced fracture. For precise assessment, a pre-alignment of both datasets is a crucial step. We propose a contour extraction pipeline to estimate the joint space location for a prealignment of fluoroscopic C-arm projections containing the upper ankle joint. A quadtree-based hierarchical variance comparison extracts potential feature points and a Hough transform is applied to identify bone shaft lines together with the tibiotalar joint space. By using this information we can define the coarse orientation of the projections independent from the ankle pose during acquisition in order to align those images to the volume of the fractured ankle. The proposed method was evaluated on thirteen cadaveric datasets consisting of 100 projections each with manually adjusted image planes by three trauma surgeons. The results show that the method can be used to detect the joint space orientation. The correlation between angle deviation and anatomical projection direction gives valuable input on the acquisition direction for future clinical experiments.

Direct observation of the myosin Va recovery stroke that contributes to unidirectional stepping along actin.

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Katsuyuki Shiroguchi

2011-04-01

Full Text Available Myosins are ATP-driven linear molecular motors that work as cellular force generators, transporters, and force sensors. These functions are driven by large-scale nucleotide-dependent conformational changes, termed "strokes"; the "power stroke" is the force-generating swinging of the myosin light chain-binding "neck" domain relative to the motor domain "head" while bound to actin; the "recovery stroke" is the necessary initial motion that primes, or "cocks," myosin while detached from actin. Myosin Va is a processive dimer that steps unidirectionally along actin following a "hand over hand" mechanism in which the trailing head detaches and steps forward ∼72 nm. Despite large rotational Brownian motion of the detached head about a free joint adjoining the two necks, unidirectional stepping is achieved, in part by the power stroke of the attached head that moves the joint forward. However, the power stroke alone cannot fully account for preferential forward site binding since the orientation and angle stability of the detached head, which is determined by the properties of the recovery stroke, dictate actin binding site accessibility. Here, we directly observe the recovery stroke dynamics and fluctuations of myosin Va using a novel, transient caged ATP-controlling system that maintains constant ATP levels through stepwise UV-pulse sequences of varying intensity. We immobilized the neck of monomeric myosin Va on a surface and observed real time motions of bead(s attached site-specifically to the head. ATP induces a transient swing of the neck to the post-recovery stroke conformation, where it remains for ∼40 s, until ATP hydrolysis products are released. Angle distributions indicate that the post-recovery stroke conformation is stabilized by ≥ 5 k(BT of energy. The high kinetic and energetic stability of the post-recovery stroke conformation favors preferential binding of the detached head to a forward site 72 nm away. Thus, the recovery

The temporomandibular joint

International Nuclear Information System (INIS)

Campbell, W.

1984-01-01

Whilst the temporomandibular joint is in many ways unique, it is subject to all the diseases and disorders found in joints in other parts of the human skeleton. By far the most common disorder is injury, followed by arthropathy, acute and chronic dislocations, ankylosis, and in rare instances, neoplasms. The diagnosis and management of the temporomandibular joint are the primary responsibility of the oral surgeon. Nevertheless, this anatomical region is an area in which the cooperation of medical and dental disciplines may be required for the satisfactory conclusion of treatment. The more so when the disease process involves either associated psychosomatic illness or malignancy. The mainstay of the diagnosis is a careful radiological examination of the joint. There exists a delicate relationship between the dentition, the muscles of mastication, and the temporomandibular articulation, which is controlled by arthrokinetic reflex activity of the branches of the 5th cranial nerve. Imbalance between one or more of the components of this integrated system frequently leads to disturbances in function. Pain-dysfunction disorders constitute the larger part of temporomandibular joint disturbances generally encountered

Crafting continuity and change in Saudi society: Joint parent-youth transition-to-adulthood projects.

Science.gov (United States)

Khalifa, Hind; Alnuaim, Aziza A; Young, Richard A; Marshall, Sheila K; Popadiuk, Natalee

2018-02-01

Little is known about the transition to adulthood in traditional, developing countries such as Saudi Arabia. Previous research in other countries has revealed the importance of considering parents' support during the transition to adulthood. Thus, the purpose of this research was to examine how two generations negotiated the transition to adulthood. We asked the research question, What are the joint projects in which parents and youth plan and act on their plans for the youth's future? We used the action project method, an established qualitative approach, to answer these questions by observing the joint conversations of 14 parent and youth dyads. Our results provided evidence of an overarching higher level goal, or intentional framework, of crafting generational change and continuity within which participants' joint projects were embedded. Joint projects were organized into three groups: (a) negotiating educational and career futures, (b) promoting gender roles and marriage, and (c) shaping independence. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. All rights reserved.

A musculoskeletal lumbar and thoracic model for calculation of joint kinetics in the spine

International Nuclear Information System (INIS)

Kim, Yong Cheol; Ta, Duc manh; Koo, Seung Bum; Jung Moon Ki

2016-01-01

The objective of this study was to develop a musculoskeletal spine model that allows relative movements in the thoracic spine for calculation of intra-discal forces in the lumbar and thoracic spine. The thoracic part of the spine model was composed of vertebrae and ribs connected with mechanical joints similar to anatomical joints. Three different muscle groups around the thoracic spine were inserted, along with eight muscle groups around the lumbar spine in the original model from AnyBody. The model was tested using joint kinematics data obtained from two normal subjects during spine flexion and extension, axial rotation and lateral bending motions beginning from a standing posture. Intra-discal forces between spine segments were calculated in a musculoskeletal simulation. The force at the L4-L5 joint was chosen to validate the model's prediction against the lumbar model in the original AnyBody model, which was previously validated against clinical data.

A musculoskeletal lumbar and thoracic model for calculation of joint kinetics in the spine

Energy Technology Data Exchange (ETDEWEB)

Kim, Yong Cheol; Ta, Duc manh; Koo, Seung Bum [Chung-Ang University, Seoul (Korea, Republic of); Jung Moon Ki [AnyBody Technology A/S, Aalborg (Denmark)

2016-06-15

The objective of this study was to develop a musculoskeletal spine model that allows relative movements in the thoracic spine for calculation of intra-discal forces in the lumbar and thoracic spine. The thoracic part of the spine model was composed of vertebrae and ribs connected with mechanical joints similar to anatomical joints. Three different muscle groups around the thoracic spine were inserted, along with eight muscle groups around the lumbar spine in the original model from AnyBody. The model was tested using joint kinematics data obtained from two normal subjects during spine flexion and extension, axial rotation and lateral bending motions beginning from a standing posture. Intra-discal forces between spine segments were calculated in a musculoskeletal simulation. The force at the L4-L5 joint was chosen to validate the model's prediction against the lumbar model in the original AnyBody model, which was previously validated against clinical data.

Effect of exoskeletal joint constraint and passive resistance on metabolic energy expenditure: Implications for walking in paraplegia.

Directory of Open Access Journals (Sweden)

Sarah R Chang

Full Text Available An important consideration in the design of a practical system to restore walking in individuals with spinal cord injury is to minimize metabolic energy demand on the user. In this study, the effects of exoskeletal constraints on metabolic energy expenditure were evaluated in able-bodied volunteers to gain insight into the demands of walking with a hybrid neuroprosthesis after paralysis. The exoskeleton had a hydraulic mechanism to reciprocally couple hip flexion and extension, unlocked hydraulic stance controlled knee mechanisms, and ankles fixed at neutral by ankle-foot orthoses. These mechanisms added passive resistance to the hip (15 Nm and knee (6 Nm joints while the exoskeleton constrained joint motion to the sagittal plane. The average oxygen consumption when walking with the exoskeleton was 22.5 ± 3.4 ml O2/min/kg as compared to 11.7 ± 2.0 ml O2/min/kg when walking without the exoskeleton at a comparable speed. The heart rate and physiological cost index with the exoskeleton were at least 30% and 4.3 times higher, respectively, than walking without it. The maximum average speed achieved with the exoskeleton was 1.2 ± 0.2 m/s, at a cadence of 104 ± 11 steps/min, and step length of 70 ± 7 cm. Average peak hip joint angles (25 ± 7° were within normal range, while average peak knee joint angles (40 ± 8° were less than normal. Both hip and knee angular velocities were reduced with the exoskeleton as compared to normal. While the walking speed achieved with the exoskeleton could be sufficient for community ambulation, metabolic energy expenditure was significantly increased and unsustainable for such activities. This suggests that passive resistance, constraining leg motion to the sagittal plane, reciprocally coupling the hip joints, and weight of exoskeleton place considerable limitations on the utility of the device and need to be minimized in future designs of practical hybrid neuroprostheses for walking after paraplegia.

Benign joint hypermobility syndrome

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Iwona Słowińska

2014-11-01

Full Text Available Benign joint hypermobility syndrome (BJHS, commonly known as loose ligament syndrome, is a non-inflammatory rheumatic condition. It is characterised by a greater than normal range of motion of the joints of the limbs and spine. The prevalence of the syndrome in preschool-age children is estimated to be between 2% and 30%, depending on ethnic background (with higher prevalence in Asian and African populations, occurring most often in families with a history of the condition and more frequently in girls. This paper presents a case report of a 12-year-old girl. A broad differential diagnostic approach to recurrent joint inflammation with joint effusion and pain made it possible to establish a diagnosis of benign joint hypermobility syndrome. The child met the Brighton criteria; her Beighton score was 7 out of 9. Patient education aimed at eliminating abnormal joint movement and an appropriate rehabilitation programme play key roles in the treatment of BJHS.

Astronomical sketching a step-by-step introduction

CERN Document Server

Handy, Richard; Perez, Jeremy; Rix, Erika; Robbins, Sol

2007-01-01

This book presents the amateur with fine examples of astronomical sketches and step-by-step tutorials in each medium, from pencil to computer graphics programs. This unique book can teach almost anyone to create beautiful sketches of celestial objects.

Assessment of Musculoskeletal Function and its Correlation with Radiological Joint Score in Children with Hemophilia A.

Science.gov (United States)

Gupta, Samriti; Garg, Kapil; Singh, Jagdish

2015-12-01

To evaluate the functional independence of children with hemophilia A and its correlation to radiological joint score. The present cross sectional study was conducted at SPMCHI, SMS Medical College, Jaipur, India. Children in the age group of 4-18 y affected with severe, moderate and mild hemophilia A and with a history of hemarthrosis who attended the OPD, emergency or got admitted in wards of SPMCHI, SMS Medical College were examined. Musculoskeletal function was measured in 98 patients using Functional Independence Score in Hemophilia (FISH) and index joints (joints most commonly affected with repeated bleeding) were assessed radiologically with plain X rays using Pettersson score. The mean FISH score was 28.07 ± 3.90 (range 17-32) with squatting, running and step climbing as most affected tasks. The mean Pettersson score was 3.8 ± 3.2. A significant correlation was found between mean Pettersson score and FISH (r = -0.875, P hemophilia A.

Experimental investigation on the failure of T-joints at elevated temperature under unaxial loading

Science.gov (United States)

Bahri, N. F.; Afendi, M.; Razlan, Z. M.; Nor, A.; Baharuddin, S. A.

2017-09-01

In this study, the mechanical properties and maximum failure load of a bulk and T-joints subjected to tensile loading were investigated experimentally. A bulk and the T-joint specimens were fabricated and tested in order to investigate the effects of temperature conditions on the failure of the joints. The adherent and adhesive used for T-joint are 304 L stainless steel and Hysol E 214 HP with the adhesive thickness of 1.0 mm. The tensile test of the bulk specimen and adhesively T-joint were conducted by using a universal testing machine (UTM) at room temperature (RT), 55 °C, 75 °C, 100 °C and 120 °C, respectively. It was found that as the temperature increases, the failure force strength decreases for bulk and T-joint specimen. Data obtained from the tests at 120 °C showed the failure force of the bulk adhesive decreased by approximately 44 % compared to the specimen tested at RT. Next, the bulk of Hysol failure force result was compared with Araldite at RT and 100 °C. Araldite data was taken from the previous study [1]. It has also been found that the bulk for Hysol has higher failure force compared to Araldite at RT and 100 °C.

Workspace location influences joint coordination during reaching in post-stroke hemiparesis

Science.gov (United States)

Reisman, Darcy S.; Scholz, John P.

2006-01-01

The purpose of this study was to determine the influence of workspace location on joint coordination in persons with post-stroke hemiparesis when trunk motion was required to complete reaches beyond the arm’s functional reach length. Seven subjects with mild right hemiparesis following a stroke and seven age and gender matched control subjects participated. Joint motions and characteristics of hand and trunk movement were measured over multiple repetitions. The variance (across trials) of joint combinations was partitioned into two components at every point in the hand’s trajectory using the uncontrolled manifold approach; the first component is a measure of the extent to which equivalent joint combinations are used to control a given hand path, and reflects performance flexibility. The second component of joint variance reflects the use of non-equivalent joint combinations, which lead to hand path error. Compared to the control subjects, persons with hemiparesis demonstrated a significantly greater amount of non-equivalent joint variability related to control of the hand’s path and of the hand’s position relative to the trunk when reaching toward the hemiparetic side (ipsilaterally), but not when reaching to the less involved side. The relative timing of the hand and trunk was also altered when reaching ipsilaterally. The current findings support the idea that the previously proposed “arm compensatory synergy” may be deficient in subjects with hemiparesis. This deficiency may be due to one or a combination of factors: changes in central commands that are thought to set the gain of the arm compensatory synergy; a limited ability to combine shoulder abduction and elbow extension that limits the expression of an appropriately set arm compensatory synergy; or a reduction of the necessary degrees-of-freedom needed to adequately compensate for poor trunk control when reaching ipsilaterally. PMID:16328275

The Climate for Joint Implementation. Case Studies from Russia, Ukraine, and Poland

Energy Technology Data Exchange (ETDEWEB)

Evans, M.; Legro, S.; Popov, I. [Pacific Northwest National Laboratory, Washington, DC (United States)

2000-07-01

Joint implementation (JI) can provide flexibility in meeting Kyoto Protocol commitments, and 44 nations have already participated in the UN. Framework Convention on Climate Change - Activities Implemented Jointly (AIJ) pilot. This paper surveys JI policy and projects in three countries - Russia, Ukraine, and Poland - over the past five years and examines the effects of domestic institutions, foreign policy, and investment trends on JI in each country. The institutional and economic situation in the three nations differs greatly, and these distinctions have resulted in very different circumstances for AIJ projects, affecting both their number and scope. Poland has a well-defined set of rules and procedures for JI and its economy is quite strong. Ukraine has not yet established criteria or clear procedures for AIJ project reviews although it does have an Interagency Commission on Climate Change. Ukraine's economy declined by over 40% in the 1990s. Russia's economy has also declined, to a lesser extent. Russia does have a procedure for reviewing AIJ projects, though it has temporarily halted these reviews. Countries seeking JI investment can take several steps to improve the number and quality of AIJ projects that they receive. In the long term, governments can create macroeconornic stability and a solid legal investment basis to attract investment for JI and other areas. In the short term, however, governments can undertake several simple and inexpensive steps to promote JI. Establishing clear rules and procedures for AIJ projects is an important step. So too are clearly delegating responsibility for AIJ project review and providing a single JI point of contact in the government to which investors and project developers can turn. Gaining more experience in implementing AIJ projects now is important preparation for fully implementing the Kyoto Protocol beginning in 2008. 28 refs.

Control Software for Piezo Stepping Actuators

Science.gov (United States)

Shields, Joel F.

2013-01-01

A control system has been developed for the Space Interferometer Mission (SIM) piezo stepping actuator. Piezo stepping actuators are novel because they offer extreme dynamic range (centimeter stroke with nanometer resolution) with power, thermal, mass, and volume advantages over existing motorized actuation technology. These advantages come with the added benefit of greatly reduced complexity in the support electronics. The piezo stepping actuator consists of three fully redundant sets of piezoelectric transducers (PZTs), two sets of brake PZTs, and one set of extension PZTs. These PZTs are used to grasp and move a runner attached to the optic to be moved. By proper cycling of the two brake and extension PZTs, both forward and backward moves of the runner can be achieved. Each brake can be configured for either a power-on or power-off state. For SIM, the brakes and gate of the mechanism are configured in such a manner that, at the end of the step, the actuator is in a parked or power-off state. The control software uses asynchronous sampling of an optical encoder to monitor the position of the runner. These samples are timed to coincide with the end of the previous move, which may consist of a variable number of steps. This sampling technique linearizes the device by avoiding input saturation of the actuator and makes latencies of the plant vanish. The software also estimates, in real time, the scale factor of the device and a disturbance caused by cycling of the brakes. These estimates are used to actively cancel the brake disturbance. The control system also includes feedback and feedforward elements that regulate the position of the runner to a given reference position. Convergence time for smalland medium-sized reference positions (less than 200 microns) to within 10 nanometers can be achieved in under 10 seconds. Convergence times for large moves (greater than 1 millimeter) are limited by the step rate.

Sacroiliac joint dysfunction.

Science.gov (United States)

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.

Metallic joints for very high vacuum; Joints metalliques pour ultra-vide

Energy Technology Data Exchange (ETDEWEB)

Paigne, J [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1961-07-01

After defining three main types of joint; three types of distribution of the tightening force in the clamps are demonstrated; the distribution of stresses, distortion and displacements in these clamps is then calculated by means of the theory of elasticity. This is followed by experimental results on a particular means of tightening (i.e. screw-clamps). From a brief discussion on the behaviour of the clamps it is possible finally to define other types of joint deriving from the main types originally foreseen. (author) [French] Apres avoir defini trois principaux types de joints, on met en evidence trois types de distribution des forces de serrage des brides; puis on calcule a l'aide de la theorie de l'elasticite la distribution des contraintes, deformations et deplacements dans ces brides. On donne ensuite des resultats experimentaux sur un mode de serrage particulier (cas des serres-joints). Une discussion sommaire sur le comportement des brides permet de definir finalement d'autres types de joints derivant des types principaux envisages initialement. (auteur)

Self-triggered assistive stimulus training improves step initiation in persons with Parkinson’s disease

Directory of Open Access Journals (Sweden)

Creath Robert A

2013-01-01

Full Text Available Abstract Background Prior studies demonstrated that hesitation-prone persons with Parkinson’s disease (PDs acutely improve step initiation using a novel self-triggered stimulus that enhances lateral weight shift prior to step onset. PDs showed reduced anticipatory postural adjustment (APA durations, earlier step onsets, and faster 1st step speed immediately following stimulus exposure. Objective This study investigated the effects of long-term stimulus exposure. Methods Two groups of hesitation-prone subjects with Parkinson’s disease (PD participated in a 6-week step-initiation training program involving one of two stimulus conditions: 1 Drop. The stance-side support surface was lowered quickly (1.5 cm; 2 Vibration. A short vibration (100 ms was applied beneath the stance-side support surface. Stimuli were self-triggered by a 5% reduction in vertical force under the stance foot during the APA. Testing was at baseline, immediately post-training, and 6 weeks post-training. Measurements included timing and magnitude of ground reaction forces, and step speed and length. Results Both groups improved their APA force modulation after training. Contrary to previous results, neither group showed reduced APA durations or earlier step onset times. The vibration group showed 55% increase in step speed and a 39% increase in step length which were retained 6 weeks post-training. The drop group showed no stepping-performance improvements. Conclusions The acute sensitivity to the quickness-enhancing effects of stimulus exposure demonstrated in previous studies was supplanted by improved force modulation following prolonged stimulus exposure. The results suggest a potential approach to reduce the severity of start hesitation in PDs, but further study is needed to understand the relationship between short- and long-term effects of stimulus exposure.

Joint pathology and behavioral performance in autoimmune MRL-lpr Mice.

Science.gov (United States)

Sakić, B; Szechtman, H; Stead, R H; Denburg, J A

1996-09-01

Young autoimmune MRL-lpr mice perform more poorly than age-matched controls in tests of exploration, spatial learning, and emotional reactivity. Impaired behavioral performance coincides temporally with hyperproduction of autoantibodies, infiltration of lymphoid cells into the brain, and mild arthritic-like changes in hind paws. Although CNS mechanisms have been suggested to mediate behavioral deficits, it was not clear whether mild joint pathology significantly affected behavioral performance. Previously we observed that 11-week-old MRL-lpr mice showed a trend for disturbed performance when crossing a narrow beam. The first aim of the present study was to test the significance of this trend by increasing the sample size and, second, to examine the possibility that arthritis-like changes interfere with performance in brief locomotor tasks. For the purpose of the second goal, 18-week-old mice that differ widely in severity of joint disease were selectively taken from the population and tested in beam walking and swimming tasks. It was expected that the severity of joint inflammation would be positively correlated with the degree of locomotor impairment. The larger sample size revealed that young MRL-lpr mice perform significantly more poorly than controls on the beam-walking test, as evidenced by more foot slips and longer traversing time. However, significant correlation between joint pathology scores and measures of locomotion could not be detected. The lack of such relationship suggests that mild joint pathology does not significantly contribute to impaired performance in young, autoimmune MRL-lpr mice tested in short behavioral tasks.

Cadaveric Study of the Articular Branches of the Shoulder Joint.

Science.gov (United States)

Eckmann, Maxim S; Bickelhaupt, Brittany; Fehl, Jacob; Benfield, Jonathan A; Curley, Jonathan; Rahimi, Ohmid; Nagpal, Ameet S

This cadaveric study investigated the anatomic relationships of the articular branches of the suprascapular (SN), axillary (AN), and lateral pectoral nerves (LPN), which are potential targets for shoulder analgesia. Sixteen embalmed cadavers and 1 unembalmed cadaver, including 33 shoulders total, were dissected. Following dissections, fluoroscopic images were taken to propose an anatomical landmark to be used in shoulder articular branch blockade. Thirty-three shoulders from 17 total cadavers were studied. In a series of 16 shoulders, 16 (100%) of 16 had an intact SN branch innervating the posterior head of the humerus and shoulder capsule. Suprascapular sensory branches coursed laterally from the spinoglenoid notch then toward the glenohumeral joint capsule posteriorly. Axillary nerve articular branches innervated the posterolateral head of the humerus and shoulder capsule in the same 16 (100%) of 16 shoulders. The AN gave branches ascending circumferentially from the quadrangular space to the posterolateral humerus, deep to the deltoid, and inserting at the inferior portion of the posterior joint capsule. In 4 previously dissected and 17 distinct shoulders, intact LPNs could be identified in 14 (67%) of 21 specimens. Of these, 12 (86%) of 14 had articular branches innervating the anterior shoulder joint, and 14 (100%) of 14 LPN articular branches were adjacent to acromial branches of the thoracoacromial blood vessels over the superior aspect of the coracoid process. Articular branches from the SN, AN, and LPN were identified. Articular branches of the SN and AN insert into the capsule overlying the glenohumeral joint posteriorly. Articular branches of the LPN exist and innervate a portion of the anterior shoulder joint.

Acromioclavicular joint separation

Directory of Open Access Journals (Sweden)

Devan Pandya, BS

2018-04-01

Full Text Available History of present illness: A 30-year-old male was brought in by ambulance to the emergency department as a trauma activation after a motorcycle accident. The patient was the helmeted rider of a motorcycle traveling at an unknown speed when he lost control and was thrown off his vehicle. He denied loss of consciousness, nausea, or vomiting. The patient’s vital signs were stable and his only complaint was pain around his left shoulder. On exam, the patient had a prominent left clavicle without skin compromise. He had adequate range of motion in the left shoulder with moderate pain, and his left upper extremity was neurovascularly intact. Significant findings: Plain films of the left shoulder showed elevation of the left clavicle above the acromion. There was an increase in the acromioclavicular (AC and coracoclavicular (CC distances (increased joint distances marked with red and blue arrows, respectively. A normal AC joint measures 1-3 mm whereas a normal CC distance measures 11-13 mm.1 The injury was classified as a Rockwood type III AC joint separation. Discussion: The AC joint is a synovial joint between an oval facet on the acromion and a similar facet on the distal end of the clavicle. Horizontal stability is provided by the AC joint while axial stability is provided by the CC joint.2,3 AC joint injuries account for about 9%-12% of shoulder girdle injuries, and the most common mechanism is direct trauma.4,5 Initial evaluation with imaging includes plain films with three views: the anterior-posterior (AP view with the shoulder in internal and external rotation as well as an axillary, or scapula-Y view (sensitivity 40%, specificity 90% for all films.6,7 AC joint injuries are classified by the Rockwood system.8 Type I involves a sprain or incomplete tear of the AC ligaments with an intact CC ligament. The AC joint appears normal on X-ray, but can become widened with stress, achieved by having the patient hold a 10-15 pound weight from each

Hip joint injection

Science.gov (United States)

... 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, ...

Comprehensive joint feedback control for standing by functional neuromuscular stimulation-a simulation study.

Science.gov (United States)

Nataraj, Raviraj; Audu, Musa L; Kirsch, Robert F; Triolo, Ronald J

2010-12-01

Previous investigations of feedback control of standing after spinal cord injury (SCI) using functional neuromuscular stimulation (FNS) have primarily targeted individual joints. This study assesses the potential efficacy of comprehensive (trunk, hips, knees, and ankles) joint feedback control against postural disturbances using a bipedal, 3-D computer model of SCI stance. Proportional-derivative feedback drove an artificial neural network trained to produce muscle excitation patterns consistent with maximal joint stiffness values achievable about neutral stance given typical SCI muscle properties. Feedback gains were optimized to minimize upper extremity (UE) loading required to stabilize against disturbances. Compared to the baseline case of maximum constant muscle excitations used clinically, the controller reduced UE loading by 55% in resisting external force perturbations and by 84% during simulated one-arm functional tasks. Performance was most sensitive to inaccurate measurements of ankle plantar/dorsiflexion position and hip ab/adduction velocity feedback. In conclusion, comprehensive joint feedback demonstrates potential to markedly improve FNS standing function. However, alternative control structures capable of effective performance with fewer sensor-based feedback parameters may better facilitate clinical usage.

Corrosion Behavior of Welded Joints for Cargo Oil Tanks of Crude Oil Carrier

Institute of Scientific and Technical Information of China (English)

Jin-shan WEI; Yan-chang QI; Zhi-ling TIAN; Yun PENG

2016-01-01

E32 grade corrosion resistant steel was welded with welding wires with three different S contents.The mi-crostructure,mechanical properties,inclusions,and corrosion behavior of welded joint were investigated.The joint coupon corrosion test and potentiodynamic polarization test were carried out under the simulated corrosion environ-ment of the inner bottom plates of cargo oil tanks.The pitting initiation and propagation mechanism of the weld metal were studied by scanning electron microscopy and infinite focus.The results indicated that the microstructures of three kinds of weld metals are all composed of acicular ferrite,ferrite side-plate and proeutectoid ferrite.The micro-structure of heat-affected zone is composed predominantly of bainite.Joint welded with low S filler wire has good me-chanical properties.S can decrease free corrosion potential and increase the corrosion tendency.The pitting initiation is oxide inclusion or sulfide-oxide inclusion complex.S can induce the formation of occluded area and promote the corrosion propagation.The chemical compositions of weld metal is similar to base metal,which can limit the galvanic corrosion between weld metal and base metal,and avoid formation of corrosion step.

Application of stepping motor

International Nuclear Information System (INIS)

1980-10-01

This book is divided into three parts, which is about practical using of stepping motor. The first part has six chapters. The contents of the first part are about stepping motor, classification of stepping motor, basic theory og stepping motor, characteristic and basic words, types and characteristic of stepping motor in hybrid type and basic control of stepping motor. The second part deals with application of stepping motor with hardware of stepping motor control, stepping motor control by microcomputer and software of stepping motor control. The last part mentions choice of stepping motor system, examples of stepping motor, measurement of stepping motor and practical cases of application of stepping motor.

Internship guide : Work placements step by step

NARCIS (Netherlands)

Haag, Esther

2013-01-01

Internship Guide: Work Placements Step by Step has been written from the practical perspective of a placement coordinator. This book addresses the following questions : what problems do students encounter when they start thinking about the jobs their degree programme prepares them for? How do you

Microsoft Office professional 2010 step by step

CERN Document Server

Cox, Joyce; Frye, Curtis

2011-01-01

Teach yourself exactly what you need to know about using Office Professional 2010-one step at a time! With STEP BY STEP, you build and practice new skills hands-on, at your own pace. Covering Microsoft Word, PowerPoint, Outlook, Excel, Access, Publisher, and OneNote, this book will help you learn the core features and capabilities needed to: Create attractive documents, publications, and spreadsheetsManage your e-mail, calendar, meetings, and communicationsPut your business data to workDevelop and deliver great presentationsOrganize your ideas and notes in one placeConnect, share, and accom

Densities of accessible final states for multi-step compound reactions

International Nuclear Information System (INIS)

Maoming De; Guo Hua

1993-01-01

The densities of accessible final states for calculations of multi-step compound reactions are derived. The Pauli exclusion principle is taken into account in the calculations. The results are compared with a previous author's results and the effect of the Pauli exclusion principle is investigated. (Author)

Subfracture insult to the human cadaver patellofemoral joint produces occult injury.

Science.gov (United States)

Atkinson, P J; Haut, R C

1995-11-01

The current criterion used by the automotive industry for injury to the lower extremity is based on visible bone fracture. Studies suggest, however, that chronic joint degeneration may occur after subfracture impact loads on the knee. We hypothesized that subfracture loading of the patellofemoral joint could result in previously undocumented microtrauma in areas of high contact pressure. In the current study, seven patellofemoral joints from human cadavers were subjected to impact with successively greater energy until visible fracture was noted. Transverse and comminuted fractures of the patella were noted at 6.7 kN of load. Approximately 45% of the impact energy then was delivered to the contralateral joint. Subfracture loads of 5.2 kN resulted in no gross bone fracture in five of seven specimens. Histological examination of the patellae horizontal split fracture in the subchondral bone, at the tidemark, or at the interface of calcified cartilage and subchondral bone. The trauma appeared predominantly on the lateral facet, adjacent to or directly beneath preexisting fibrillation of the articular surface. Surface fibrillation was noted in histological sections of control patellae (not subjected to impact loading), but occult damages were not observed. Although the mechanism of this occult trauma is unknown, similar damage has been shown to occur from direct shear loading. As these microcracks can potentiate a disease process in the joint, this study may suggest that the current criterion for injury, based on bone fracture alone, is not sufficiently conservative.

Parameter identification for joint elements in a revolute-joint detector manipulator

International Nuclear Information System (INIS)

Preissner, C.; Shu, D.; Royston, T.

2005-01-01

A revolute-joint robot is being developed for the spatial positioning of an x-ray detector at the Advanced Photon Source. Commercially available revolute-joint manipulators do not meet our size, positioning, or payload specifications. One idea being considered is the modification of a commercially available robot, with the goal of improving the repeatability and trajectory accuracy. Theoretical, computational, and experimental procedures are being used to (1) identify, (2) simulate the dynamics of an existing robot system using a multibody approach, and eventually (3) design an improved version, with low dynamic positioning uncertainty. A key aspect of the modeling and performance prediction is accurate stiffness and damping values for the robot joints. This paper discusses the experimental identification of the stiffness and damping parameters for one robot harmonic drive joint

Canine stifle joint biomechanics associated with tibial plateau leveling osteotomy predicted by use of a computer model.

Science.gov (United States)

Brown, Nathan P; Bertocci, Gina E; Marcellin-Little, Denis J

2014-07-01

To evaluate effects of tibial plateau leveling osteotomy (TPLO) on canine stifle joint biomechanics in a cranial cruciate ligament (CrCL)-deficient stifle joint by use of a 3-D computer model simulating the stance phase of gait and to compare biomechanics in TPLO-managed, CrCL-intact, and CrCL-deficient stifle joints. Computer simulations of the pelvic limb of a Golden Retriever. A previously developed computer model of the canine pelvic limb was used to simulate TPLO stabilization to achieve a tibial plateau angle (TPA) of 5° (baseline value) in a CrCL-deficient stifle joint. Sensitivity analysis was conducted for tibial fragment rotation of 13° to -3°. Ligament loads, relative tibial translation, and relative tibial rotation were determined and compared with values for CrCL-intact and CrCL-deficient stifle joints. TPLO with a 5° TPA converted cranial tibial translation to caudal tibial translation and increased loads placed on the remaining stifle joint ligaments, compared with results for a CrCL-intact stifle joint. Lateral collateral ligament load was similar, medial collateral ligament load increased, and caudal cruciate ligament load decreased after TPLO, compared with loads for a CrCL-deficient stifle joint. Relative tibial rotation after TPLO was similar to that of a CrCL-deficient stifle joint. Stifle joint biomechanics were affected by TPLO fragment rotation. In the model, stifle joint biomechanics were partially improved after TPLO, compared with CrCL-deficient stifle joint biomechanics, but TPLO did not fully restore CrCL-intact stifle joint biomechanics. Overrotation of the tibial fragment negatively influenced stifle joint biomechanics by increasing caudal tibial translation.

Histological and autoradiographic studies on rat joints after experimental nervous shock

International Nuclear Information System (INIS)

Kohl, C.

1981-01-01

22 SPF-Wistar-rats of both sexes, ranging in age from 49 to 56 days, were used in this investigation. Of these, 6 served as controls. The remaining 16 rats received i.v. injections of E. coli-neurotoxin serotyp 0 139 : K 82 (B). 6 rats died in acute shock. The surviving animals received 4 injections of the neurotoxin. The maximum weight loss 24 h p.i. amounted to an average of 8.3% in the females and 10.4% in the males. The clinical symptoms after the inducement of skock are slight to severe apathy, rough coat, dyspnoe and nervous symptoms which are expressed in various degrees of oversensitivity to touch or sound. The light microscopic examination of the synovial membrane from control animals coincides with the findings of previous investigations. In acute shock the joints show a middle to high degree of hyperemia, slight sticking effect, and isolated microthrombi in the vessels of the subsynoviocytic tissue as well as increased exsudation in the joint cavities. Edemas of the subsynoviocytic tissue are found to a small extent. The joints of animals in protracted shock show none of the changes evident in acute shock. Autoradiological examinations were performed on 13 rats which had been injected with 1 μCi/g body weight 3H-thymidine 1 hour before killing. Joints were embedded in paraffin- and methyl-methacrylat. Comparison cuts from the same stifle joint resulted each time in reproducable labeling indices. This can be taken as a confirmation of the applicability of 3H-autoradiography in the case of joint cuts embedded in methacrylat. (orig./MG) [de

Dynamic modeling method of the bolted joint with uneven distribution of joint surface pressure

Science.gov (United States)

Li, Shichao; Gao, Hongli; Liu, Qi; Liu, Bokai

2018-03-01

The dynamic characteristics of the bolted joints have a significant influence on the dynamic characteristics of the machine tool. Therefore, establishing a reasonable bolted joint dynamics model is helpful to improve the accuracy of machine tool dynamics model. Because the pressure distribution on the joint surface is uneven under the concentrated force of bolts, a dynamic modeling method based on the uneven pressure distribution of the joint surface is presented in this paper to improve the dynamic modeling accuracy of the machine tool. The analytic formulas between the normal, tangential stiffness per unit area and the surface pressure on the joint surface can be deduced based on the Hertz contact theory, and the pressure distribution on the joint surface can be obtained by the finite element software. Futhermore, the normal and tangential stiffness distribution on the joint surface can be obtained by the analytic formula and the pressure distribution on the joint surface, and assigning it into the finite element model of the joint. Qualitatively compared the theoretical mode shapes and the experimental mode shapes, as well as quantitatively compared the theoretical modal frequencies and the experimental modal frequencies. The comparison results show that the relative error between the first four-order theoretical modal frequencies and the first four-order experimental modal frequencies is 0.2% to 4.2%. Besides, the first four-order theoretical mode shapes and the first four-order experimental mode shapes are similar and one-to-one correspondence. Therefore, the validity of the theoretical model is verified. The dynamic modeling method proposed in this paper can provide a theoretical basis for the accurate dynamic modeling of the bolted joint in machine tools.

Towards the joint use of ICD and ICF: a call for contribution.

Science.gov (United States)

Kohler, Friedbert; Selb, Melissa; Escorpizo, Reuben; Kostanjsek, Nenad; Stucki, Gerold; Riberto, Marcelo

2012-10-01

To optimize patient functioning, rehabilitation professionals often rely on measurements of functioning as well as on classifications. Although the International Classification of Diseases (ICD) and the International Classification of Functioning, Disability and Health (ICF) are used, their joint use has yet to become an established practice. To encourage their joint use in daily practice, the World Health Organization (WHO) has invited all rehabilitation practitioners worldwide to support the ICD-11 revision process by identifying the ICF categories that correspond to specific rehabilitation-relevant health conditions. The first step in completing this task, generating the list of these health conditions, was taken at a February 2012 workshop in São Paulo, Brazil. The objectives of this paper are to present the results of the São Paulo workshop, and to invite practitioners to participate in the ICD-ICF joint use initiative. Alternating plenary and small working group sessions were held and 103 rehabilitation-relevant health conditions were identified. With this list available, WHO together with the International Society of Physical and Rehabilitation Medicine (ISPRM), is reaching out to clinicians of all rehabilitation disciplines to take on the challenge of identifying the ICF categories for at least one of the health conditions listed.

Quantifying the impact of transient joint symptoms, chronic joint symptoms, and arthritis: a population-based approach.

Science.gov (United States)

Busija, Lucy; Buchbinder, Rachelle; Osborne, Richard H

2009-10-15

To estimate the prevalence and co-occurrence of self-reported doctor-diagnosed arthritis, chronic joint symptoms (pain, aching, stiffness, or swelling on most days for a month), and transient joint symptoms (pain, aching, stiffness, or swelling but not on most days for a month), and to compare the sociodemographic characteristics, activity limitations, and health-related quality of life (HRQOL) of people with joint conditions with those who have no self-reported doctor-diagnosed arthritis and no joint symptoms. Data from the 2004 population-based South Australian Health Omnibus Survey (n = 2,840, ages 18-96 years) were used in the study. Activity limitations were assessed using 10 activity limitations questions from the Short Form 36 health survey. HRQOL was assessed using the Assessment of Quality of Life scale. Half of all respondents reported having joint problems, with 26%, 11%, and 13% reporting self-reported doctor-diagnosed arthritis, chronic joint symptoms, and transient joint symptoms, respectively. Chronic joint conditions (self-reported doctor-diagnosed arthritis and chronic joint symptoms) accounted for 74% of all joint problems and were associated with higher odds of activity limitations and poorer HRQOL. The frequency of transient and chronic joint symptoms was highest among middle-aged participants (ages 45-54 years for transient and 45-64 years for chronic joint symptoms) and those who had a body mass index in the obese range. Prevalence of self-reported doctor-diagnosed arthritis increased with age and was higher among women and those who were overweight or obese. This study documented the high prevalence and impact of joint conditions in the community. Chronic joint conditions affect daily life and are substantial barriers for effective public health interventions aimed at reducing obesity and inactivity.

Required Steps of Managing International Equity Placement Strategic Alliance

Directory of Open Access Journals (Sweden)

Harimukti Wandebori

2012-01-01

Full Text Available The purpose of the research is to unravel the steps of managing international equity placement strategic alliance (IEPSA. The steps of managing an IEPSA are obtained by conducting theoretical review. The theoretical reviews consist of theory of strategic alliance; definition, classification, and finding definition of an IEPSA, political and analytical considerations and the necessary steps. These steps of managing IEPSA can be classified into analyzing of macro consideration, micro consideration, domestic company’s stakeholder support, cultural understanding, strategic planning, internal support, human resource management, organizational arrangement, management control system, evolved cultural understanding, and evaluating results. In this research, the domestic partners who formed the IEPSAs are limited to State-Owned Enterprises (SOEs. The IEPSA was one of the means of privatization. The research will be beneficial for both foreign and domestic partners who form an IEPSA in the previous SOEs. By knowing the steps of managing the IEPSA both partners will be able to secure a successful implementation of IEPSA. By identifying the steps of managing the IEPSA, the stakeholder will not see IEPSA as threat rather as an opportunity to improve performance, to create synergy, and generate benefits for both partners and stakeholder. By knowing the necessary steps of managing the IEPSA, the stakeholder including society and politician will envisage the IEPSA as a means of effectively improving the SOEs’ performances.The research was espected to provide contributions for the research on strategic alliances. Apparently, there exist no literatures discussing about IEPSA in the domain of strategic alliances. Keywords: strategic alliance, equity placement, international equity placement strategic alliance, privatization, steps of international equity placement strategic alliance, state-owned enterprises

The transition to adulthood of young adults with IDD: Parents' joint projects.

Science.gov (United States)

Young, Richard A; Marshall, Sheila K; Stainton, Tim; Wall, Jessie M; Curle, Deirdre; Zhu, Ma; Munro, David; Murray, John; El Bouhali, Asmae; Parada, Filomena; Zaidman-Zait, Anat

2018-03-01

Parents have found the transition to adulthood for their sons or daughters with intellectual and/or developmental disabilities (IDD) particularly challenging. The literature has not examined how parents work together and with others in face of this transition nor has it highlighted parental goals in this process. This study used a perspective based on joint, goal-direct action to describe the projects that Canadian parents engaged in together and with others relative to this transition. Using the qualitative action-project method, joint projects between parents and with others were identified from their conversations and followed for 6 months. Three groups of projects were described: equipping the young adult for adult life, connecting for personal support and managing day-to-day while planning for the future. Parents act together and with others relative to the transition to adulthood of their young adult children with IDD. These projects are complex and differ in goals, steps, resources and emotional regulation and motivation. © 2017 John Wiley & Sons Ltd.

Implementation of the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management

International Nuclear Information System (INIS)

Stewart, L.; Tonkay, D.

2004-01-01

This paper discusses the implementation of the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management. The Joint Convention: establishes a commitment with respect to safe management of spent nuclear fuel and radioactive waste; requires the Parties to ''take appropriate steps'' to ensure the safety of their spent fuel and waste management activities, but does not delineate standards the Parties must meet; and seeks to attain, through its Contracting Parties, a higher level of safety with respect to management of their spent nuclear fuel, disused sealed sources, and radioactive waste

Required Steps of Managing International Equity Placement Strategic Alliance

Directory of Open Access Journals (Sweden)

Harimukti Wandebori

2011-12-01

Full Text Available The purpose of the research is to unravel the steps of managing international equity placement strategic alliance (IEPSA. The steps of managing an IEPSA are obtained by conducting theoretical review. The theoretical reviews consist of theory of strategic alliance; definition, classification, and finding definition of an IEPSA, political and analytical considerations and the necessary steps. These steps of managing IEPSA can be classified into analyzing of macro consideration, micro consideration, domestic company’s stakeholder support, cultural understanding, strategic planning, internal support, human resource management, organizational arrangement, management control system, evolved cultural understanding, and evaluating results. In this research, the domestic partners who formed the IEPSAs are limited to State-Owned Enterprises (SOEs. The IEPSA was one of the means of privatization. The research will be beneficial for both foreign and domestic partners who form an IEPSA in the previous SOEs. By knowing the steps of managing the IEPSA both partners will be able to secure a successful implementation of IEPSA. By identifying the steps of managing the IEPSA, the stakeholder will not see IEPSA as threat rather as an opportunity to improve performance, to create synergy, and generate benefits for both partners and stakeholder. By knowing the necessary steps of managing the IEPSA, the stakeholder including society and politician will envisage the IEPSA as a means of effectively improving the SOEs’ performances.The research was espected to provide contributions for the research on strategic alliances. Apparently, there exist no literatures discussing about IEPSA in the domain of strategic alliances.

One step replica symmetry breaking and extreme order statistics of logarithmic REMs

Directory of Open Access Journals (Sweden)

Xiangyu Cao, Yan V. Fyodorov, Pierre Le Doussal

2016-12-01

Full Text Available Building upon the one-step replica symmetry breaking formalism, duly understood and ramified, we show that the sequence of ordered extreme values of a general class of Euclidean-space logarithmically correlated random energy models (logREMs behave in the thermodynamic limit as a randomly shifted decorated exponential Poisson point process. The distribution of the random shift is determined solely by the large-distance ("infra-red", IR limit of the model, and is equal to the free energy distribution at the critical temperature up to a translation. the decoration process is determined solely by the small-distance ("ultraviolet", UV limit, in terms of the biased minimal process. Our approach provides connections of the replica framework to results in the probability literature and sheds further light on the freezing/duality conjecture which was the source of many previous results for log-REMs. In this way we derive the general and explicit formulae for the joint probability density of depths of the first and second minima (as well its higher-order generalizations in terms of model-specific contributions from UV as well as IR limits. In particular, we show that the second min statistics is largely independent of details of UV data, whose influence is seen only through the mean value of the gap. For a given log-correlated field this parameter can be evaluated numerically, and we provide several numerical tests of our theory using the circular model of $1/f$-noise.

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

Science.gov (United States)

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.

MP Joint Arthritis

Science.gov (United States)

... All Topics A-Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is a Hand Surgeon? What is a Hand Therapist? Media Find a Hand Surgeon Home Anatomy MP Joint Arthritis Email to a friend * required ...

Stimulated Brillouin scattering continuous wave phase conjugation in step-index fiber optics.

Science.gov (United States)

Massey, Steven M; Spring, Justin B; Russell, Timothy H

2008-07-21

Continuous wave (CW) stimulated Brillouin scattering (SBS) phase conjugation in step-index optical fibers was studied experimentally and modeled as a function of fiber length. A phase conjugate fidelity over 80% was measured from SBS in a 40 m fiber using a pinhole technique. Fidelity decreases with fiber length, and a fiber with a numerical aperture (NA) of 0.06 was found to generate good phase conjugation fidelity over longer lengths than a fiber with 0.13 NA. Modeling and experiment support previous work showing the maximum interaction length which yields a high fidelity phase conjugate beam is inversely proportional to the fiber NA(2), but find that fidelity remains high over much longer fiber lengths than previous models calculated. Conditions for SBS beam cleanup in step-index fibers are discussed.

Lesions in canine stifle joints due to trochleoplasties as treatment for medial patellar luxation

Directory of Open Access Journals (Sweden)

Johannes Hans van der Zee

2015-07-01

Full Text Available Lesions in canine stifle joints after previous trochleoplasty surgery were documented. Infour clinical cases arthrotomies were performed due to stifle pain after previous trochleardeepening procedures. A small area of hyaline cartilage remained in the groove of the stiflesin cases where previous wedge trochleoplasties had been performed. All of the stifles hadsignificant areas of eburnation on the axial aspect of the medial trochlear ridge. The stifle jointsof a dog that was euthanased due to severe irreversible osteo-arthritis were photographed.The dog had undergone previous surgery for patellar luxation and cranial cruciate ligamentruptures. The trochlear grooves in this dog had almost no visible articular cartilage left.

The way to collisions, step by step

CERN Multimedia

2009-01-01

While the LHC sectors cool down and reach the cryogenic operating temperature, spirits are warming up as we all eagerly await the first collisions. No reason to hurry, though. Making particles collide involves the complex manoeuvring of thousands of delicate components. The experts will make it happen using a step-by-step approach.

Heads, Shoulders, Elbows, Knees, and Toes: Modular Gdf5 Enhancers Control Different Joints in the Vertebrate Skeleton.

Science.gov (United States)

Chen, Hao; Capellini, Terence D; Schoor, Michael; Mortlock, Doug P; Reddi, A Hari; Kingsley, David M

2016-11-01

Synovial joints are crucial for support and locomotion in vertebrates, and are the frequent site of serious skeletal defects and degenerative diseases in humans. Growth and differentiation factor 5 (Gdf5) is one of the earliest markers of joint formation, is required for normal joint development in both mice and humans, and has been genetically linked to risk of common osteoarthritis in Eurasian populations. Here, we systematically survey the mouse Gdf5 gene for regulatory elements controlling expression in synovial joints. We identify separate regions of the locus that control expression in axial tissues, in proximal versus distal joints in the limbs, and in remarkably specific sub-sets of composite joints like the elbow. Predicted transcription factor binding sites within Gdf5 regulatory enhancers are required for expression in particular joints. The multiple enhancers that control Gdf5 expression in different joints are distributed over a hundred kilobases of DNA, including regions both upstream and downstream of Gdf5 coding exons. Functional rescue tests in mice confirm that the large flanking regions are required to restore normal joint formation and patterning. Orthologs of these enhancers are located throughout the large genomic region previously associated with common osteoarthritis risk in humans. The large array of modular enhancers for Gdf5 provide a new foundation for studying the spatial specificity of joint patterning in vertebrates, as well as new candidates for regulatory regions that may also influence osteoarthritis risk in human populations.

Water flow in single rock joints

International Nuclear Information System (INIS)

Hakami, Eva

1989-05-01

To study the hydromechanical properties of single rock joints a technique to make transparent replicas of natural joint surfaces has been developed. Five different joint samples were replicated and studied. The aperture distribution of the joints were obtained through a measurement method provided by the transparent replicas. The principle behind the method is that a water drop with a known volume, which is placed inside a joint, will cover a certain area of the surface depending on the average size of aperture at the actual point. Flow tests were performed on the same joint replicas. The tortuousity of the flow and the velocity along single stream lines were measured using colour injections into the water flow through the joints. The equivalent hydraulic apertures determined from the flow tests where shown to be smaller than the average mechanical apertures. The velocity of the flow varies strongly between different paths over the joint depending on the spatial distribution of the apertures. The degree of matedness between the joint surfaces is an important factor influencing the channeling character of the joints. (author) (38 refs.)

Effect of joint design on ballistic performance of quenched and tempered steel welded joints

International Nuclear Information System (INIS)

Balakrishnan, M.; Balasubramanian, V.; Madhusudhan Reddy, G.

2014-01-01

Highlights: • Traditional usage of austenitic stainless steel filler for armour steel welding shows poor ballistic performance. • Earlier efforts show dubious success on ballistic resistance of armour steel joints. • Comparative evaluation of equal/unequal joint design on ballistic performance. • Effect of joint design covers the main aspects of successful bullet stoppage. - Abstract: A study was carried out to evaluate the effect of joint design on ballistic performance of armour grade quenched and tempered steel welded joints. Equal double Vee and unequal double Vee joint configuration were considered in this study. Targets were fabricated using 4 mm thick tungsten carbide hardfaced middle layer; above and below which austenitic stainless steel layers were deposited on both sides of the hardfaced interlayer in both joint configurations. Shielded metal arc welding process was used to deposit for all layers. The fabricated targets were evaluated for its ballistic performance and the results were compared in terms of depth of penetration on weld metal. From the ballistic test results, it was observed that both the targets successfully stopped the bullet penetration at weld center line. Of the two targets, the target made with unequal double Vee joint configuration offered maximum resistance to the bullet penetration at weld metal location without any bulge at the rear side. The higher volume of austenitic stainless steel front layer and the presence of hardfaced interlayer after some depth of soft austenitic stainless steel front layer is the primary reason for the superior ballistic performance of this joint

Impact of Acid Attack on the Shear Behaviour of a Carbonate Rock Joint

Science.gov (United States)

Nouailletas, O.; Perlot, C.; Rivard, P.; Ballivy, G.; La Borderie, C.

2017-06-01

The mechanical behaviour of structural discontinuities in rock mass is a key element of the stability analysis in civil engineering, petroleum engineering and mining engineering. In this paper, the mechanical analysis is coupled with the acidic attack of a rock joint associated with leakage of CO2 through a geological fault in the context of carbon sequestration. Experiments were conducted at the laboratory scale to assess the shear behaviour of degraded joint: direct shear tests were performed on rock joints that have been previously immersed into water or into an acidic solution (pH 0.2). The shear behaviour of joints is governed by the roughness of its walls: the parameters Z2, Z3, Z4 and RL characterize the rough surfaces. They are calculated from the scans of joint surfaces after and before immersion. Their comparison pointed out a slight impact of the acidic attack. However, the results of the direct shear tests show significant modifications in the shear behaviour for the degraded joints: the tangential stress peak disappears, the tangential stiffness decreases in the stress/displacement curve, and the contraction increases, the dilation angle decreases in the dilation curve. Acid attack has a greater impact on the mechanical properties of the asperities than their geometric characteristics. The results of this study will be used to improve chemo-mechanical modelling to better simulate with higher accuracy the fault stability in different cases of civil engineering, petroleum engineering and mining engineering.

Bistable Articulated Joint

Science.gov (United States)

Graighead, Norwood D., II; Preliasco, R. J.; Hult, T. D.

1986-01-01

Joint with four-bar-linkage geometry has following attributes: Springs to fully extended fully folded positions. Automatically locks in its extended position. Joint combines zero backlash, positive locking, and centerline pivoting. Used in folding tool handles, portable antenna booms, and many other deployable structures.

[Classification and Treatment of Sacroiliac Joint Dislocation].

Science.gov (United States)

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

Reliability of agriculture universal joint shafts based on temperature measuring in universal joint bearing assemblies

Directory of Open Access Journals (Sweden)

Аleksandar Asonja

2015-03-01

Full Text Available This paper presents a research into reliability calculations of agriculture double universal joint shafts based on temperature measuring in cardan-type universal joint bearing assemblies. Special laboratory equipment was developed for this research which is presented in the paper. The objective of this research was to test the real life span of universal joint shafts in the laboratory and in field, to obtain the results which can be used to improve the reliability of universal joint shafts. If the presented research were used along with maintenance measures recommended in the paper and with proper use, the level of reliability of the shafts would be 2.1 times higher. The presented results of the research showed that needle bearings, i.e. bearing assemblies of the joints, are the most critical elements on universal joint shafts and are possible causes of their lower reliability. The second universal joint is the part with the lowest reliability in the observed technical system.

Facet joint syndrome

International Nuclear Information System (INIS)

Zigrai, M.; Zakovic, J.; Brezinova, M.; Pavlovicova, M.

2002-01-01

It is the purpose of the study to demonstrate the clinical relevance of degenerative changes in the facet joint of patients with low back pain irradiating to the lower extremities, and discuss some problems relating to diagnosis and different diagnosis. 119 patients presenting the listed bellow syndromes are covered by the study: scoliosis, polytopic pain vertebral syndrome, paresis and history of trauma. all patients undergo comprehensive neurological examination with special attention focused on the spine: CT and plain x-rays are taken of the lumbosacral segment to assess the condition of the facet joints. The neurological examination demonstrates in all cases pain syndrome in the lumbar spine referred to one or both lower extremities. In 56% it is a matter of persisting pain, and in 44% - recurrent. More than half of the patients complain of sacroiliac (SI) dislocation and palpatory pain. Unilateral or bilateral degenerative changes are documented by imaging studies in all patients, including: subchondral thickening, osteopathy narrowing the lateral or central part of the spinal canal with ensuing nerve root compression. The lumbosacral zygoapophyseal joints are source of pseudoradicular pain. A correlation between clinical picture and GT changes is noted in all patients with facet joint syndrome. CT is an indispensable method in diagnosing facet joint syndrome. (authors)

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

Science.gov (United States)

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.

Diagnostic imaging of sacroiliac joints and the spine in the course of spondyloarthropathies

Science.gov (United States)

Sudoł-Szopinska, Iwona; Urbanik, Andrzej

2013-01-01

Summary Spondyloarthropathies belong to a group of rheumatic diseases, in which inflammatory changes affect mainly the sacroiliac joints, spine, peripheral joints, tendon, ligaments and capsule attachments (entheses). This group includes 6 entities: ankylosing spondylitis, arthritis associated with inflammatory bowel disease, reactive arthritis, undifferentiated spondyloarthropathy, psoriatic arthritis and juvenile spondyloarthropathy. In 2009, ASAS (Assessment in SpondyloArthritis international Society) association, published classification criteria for spondyloarthropathies, which propose standardization of clinical-diagnostic approach in the case of sacroiliitis, spondylitis and arthritis. Radiological diagnosis of inflammatory changes of sacroiliac joints is based on a 4 step radiographic grading method from 1966. According to modified New York criteria, the diagnosis of ankylosing spondylitis is made based on the presence of advanced lesions, sacroiliitis of at least 2 grade bilaterally or 3–4 unilaterally. In case of other types of spondyloarthropathies diagnosis is made based on presence of at least grade 1 changes. In MRI, active inflammation of sacroiliac joints is indicated by the presence of subchondral bone marrow edema, synovitis, bursitis, or enthesitis. ASAS discusses only the classic form of axial spondyloarthropathies, which is ankylosing spondylitis. To quantify radiological inflammatory changes in the course of the disease, Stoke Ankylosing spondylitis classification Spinal Score (SASSS) is recommended. The signs of inflammation and scarrying of the spinal cord in the course of ankylosing spondylitis, present in MRI include: bone marrow edema, sclerosis, fat metaplasia, formation of syndesmophytes, and ankylosis. PMID:23807884

Diagnostic imaging of sacroiliac joints and the spine in the course of spondyloarthropathies

International Nuclear Information System (INIS)

Sudoł-Szopinska, Iwona; Urbanik, Andrzej

2013-01-01

Spondyloarthropathies belong to a group of rheumatic diseases, in which inflammatory changes affect mainly the sacroiliac joints, spine, peripheral joints, tendon, ligaments and capsule attachments (entheses). This group includes 6 entities: ankylosing spondylitis, arthritis associated with inflammatory bowel disease, reactive arthritis, undifferentiated spondyloarthropathy, psoriatic arthritis and juvenile spondyloarthropathy. In 2009, ASAS (Assessment in SpondyloArthritis international Society) association, published classification criteria for spondyloarthropathies, which propose standardization of clinical-diagnostic approach in the case of sacroiliitis, spondylitis and arthritis. Radiological diagnosis of inflammatory changes of sacroiliac joints is based on a 4 step radiographic grading method from 1966. According to modified New York criteria, the diagnosis of ankylosing spondylitis is made based on the presence of advanced lesions, sacroiliitis of at least 2 grade bilaterally or 3–4 unilaterally. In case of other types of spondyloarthropathies diagnosis is made based on presence of at least grade 1 changes. In MRI, active inflammation of sacroiliac joints is indicated by the presence of subchondral bone marrow edema, synovitis, bursitis, or enthesitis. ASAS discusses only the classic form of axial spondyloarthropathies, which is ankylosing spondylitis. To quantify radiological inflammatory changes in the course of the disease, Stoke Ankylosing spondylitis classification Spinal Score (SASSS) is recommended. The signs of inflammation and scarrying of the spinal cord in the course of ankylosing spondylitis, present in MRI include: bone marrow edema, sclerosis, fat metaplasia, formation of syndesmophytes, and ankylosis

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

Science.gov (United States)

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.

Septic arthritis of the adult ankle joint secondary to Salmonella enteritidis: a case report.

LENUS (Irish Health Repository)

Munigangaiah, Sudarshan

2011-09-01

Salmonella septic arthritis in healthy individuals is a rare phenomenon. However, septic arthritis of the native adult ankle joint in healthy patients has not been previously described in the published data. This is a case report of a 70-year-old farmer who presented with a 2-week history of a painful, swollen right ankle and an inability to bear weight. He had no history of ankle injury or any predisposing conditions. Joint aspirations were positive for Salmonella enteritidis that was successfully treated with right ankle arthrotomy and washout, along with a 6-week course of intravenous antibiotic therapy.

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

Science.gov (United States)

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.

Joint Attention, Social-Cognition, and Recognition Memory in Adults

Science.gov (United States)

Kim, Kwanguk; Mundy, Peter

2012-01-01

The early emerging capacity for Joint Attention (JA), or socially coordinated visual attention, is thought to be integral to the development of social-cognition in childhood. Recent studies have also begun to suggest that JA affects adult cognition as well, but methodological limitations hamper research on this topic. To address this issue we developed a novel virtual reality paradigm that integrates eye-tracking and virtual avatar technology to measure two types of JA in adults, Initiating Joint Attention (IJA) and Responding to Joint Attention (RJA). Distinguishing these types of JA in research is important because they are thought to reflect unique, as well as common constellations of processes involved in human social-cognition and social learning. We tested the validity of the differentiation of IJA and RJA in our paradigm in two studies of picture recognition memory in undergraduate students. Study 1 indicated that young adults correctly identified more pictures they had previously viewed in an IJA condition (67%) than in a RJA (58%) condition, η2 = 0.57. Study 2 controlled for IJA and RJA stimulus viewing time differences, and replicated the findings of Study 1. The implications of these results for the validity of the paradigm and research on the affects of JA on adult social-cognition are discussed. PMID:22712011

Device for measuring hole elongation in a bolted joint

Science.gov (United States)

Wichorek, Gregory R. (Inventor)

1987-01-01

A device to determine the operable failure mode of mechanically fastened lightweight composite joints by measuring the hole elongation of a bolted joint is disclosed. The double-lap joint test apparatus comprises a stud, a test specimen having a hole, two load transfer plates, and linear displacement measuring instruments. The test specimen is sandwiched between the two load transfer plates and clamped together with the stud. Spacer washers are placed between the test specimen and each load transfer plate to provide a known, controllable area for the determination of clamping forces around the hole of the specimen attributable to bolt torque. The spacer washers also provide a gap for the mounting of reference angles on each side of the test specimen. Under tensile loading, elongation of the hole of the test specimen causes the stud to move away from the reference angles. This displacement is measured by the voltage output of two linear displacement measuring instruments that are attached to the stud and remain in contact with the reference angles throughout the tensile loading. The present invention obviates previous problems in obtaining specimen deformation measurements by monitoring the reference angles to the test specimen and the linear displacement measuring instruments to the stud.

Pluralism in Theories of Responsibility: Joint Criminal Enterprise versus Joint Perpetration

NARCIS (Netherlands)

Cupido, M.; van Sliedregt, E.; Vasiliev, S.

2014-01-01

This paper scrutinizes the alleged pluralism between JCE and joint perpetration. It illustrates that the ICC and the ICTY in practice establish criminal responsibility under JCE and joint perpetration based on the participants’ cooperation in, and informed contribution to, a (criminal) organization

High-Grade Leiomyosarcoma Arising in a Previously Replanted Limb

Directory of Open Access Journals (Sweden)

Tiffany J. Pan

2015-01-01

Full Text Available Sarcoma development has been associated with genetics, irradiation, viral infections, and immunodeficiency. Reports of sarcomas arising in the setting of prior trauma, as in burn scars or fracture sites, are rare. We report a case of a leiomyosarcoma arising in an arm that had previously been replanted at the level of the elbow joint following traumatic amputation when the patient was eight years old. He presented twenty-four years later with a 10.8 cm mass in the replanted arm located on the volar forearm. The tumor was completely resected and pathology examination showed a high-grade, subfascial spindle cell sarcoma diagnosed as a grade 3 leiomyosarcoma with stage pT2bNxMx. The patient underwent treatment with brachytherapy, reconstruction with a free flap, and subsequently chemotherapy. To the best of our knowledge, this is the first case report of leiomyosarcoma developing in a replanted extremity. Development of leiomyosarcoma in this case could be related to revascularization, scar formation, or chronic injury after replantation. The patient remains healthy without signs of recurrence at three-year follow-up.

Study on the Size Effects of H-Shaped Fusion Zone of Fiber Laser Welded AZ31 Joint

Directory of Open Access Journals (Sweden)

Guang-Feng Lu

2018-03-01

Full Text Available There are two kinds of typical cross-section profiles for the fusion zone (FZ of a laser welded thin section joint, i.e., a V-shaped cross-section and an H-shaped cross-section. Previous researches indicated that tensile strength of the V-shaped joint was lower than that of the H-shaped one due to the greater heterogeneity of strain distribution on the V-shaped joint during tensile process. In this work, impacts of the aspect ratio of FZ on the mechanical properties of laser welded thin section joints with an H-shaped cross-section profile were investigated. Welding conditions corresponding to two typical H-shaped joints (i.e., Wnarrower with a narrower FZ, and Wwider with a wider FZ were decided through a laser welding orthogonal experimental plan. Then, the microstructure and properties of both joints were examined and compared. The results show that the tensile strength of joint Wnarrower and joint Wwider was about 72% and 80.9% that of the base metal, respectively. Both joints fractured in the FZ during tensile processes. The low-cycle fatigue life of the base metal, the joint Wnarrower and the joint Wwider were 3377.5 cycles, 2825 cycles and 3155.3 cycles, respectively. By using high-speed imaging, it was found that the fatigue crack of joint Wnarrower initiated and propagated inside the fusion zone, while the fatigue crack of the joint Wwider initiated at the edge of the base metal and propagated for a distance within the base metal before entering into the fusion zone. This work promoted our understanding about the influence of the weld bead shape on the properties of laser welded thin section joints.

Joint action modulates motor system involvement during action observation in 3-year-olds

NARCIS (Netherlands)

Meyer, M.; Hunnius, S.; Elk, M. van; Ede, F.L. van; Bekkering, H.

2011-01-01

When we are engaged in a joint action, we need to integrate our partner's actions with our own actions. Previous research has shown that in adults the involvement of one's own motor system is enhanced during observation of an action partner as compared to during observation of an individual actor.

The prognostic value of asymmetric laxity of the sacroiliac joints in pregnancy-related pelvic pain.

NARCIS (Netherlands)

Damen, L.; Buyruk, H.M.; Guler-Uysal, F.; Lotgering, F.K.; Snijders, C.J.; Stam, H.J.

2002-01-01

STUDY DESIGN: Prospective cohort study. OBJECTIVE: To determine the prognostic value of asymmetric laxity of the sacroiliac joints during pregnancy on pregnancy-related pelvic pain postpartum. SUMMARY OF BACKGROUND DATA: In a previous study, we observed a significant relation between asymmetric

Elbow joint instability

DEFF Research Database (Denmark)

Olsen, Bo Sanderhoff; Henriksen, M G; Søjbjerg, Jens Ole

1994-01-01

The effect of simultaneous ulnar and radial collateral ligament division on the kinematics of the elbow joint is studied in a cadaveric model. Severance of the anterior part of the ulnar collateral ligament and the annular ligament led to significant elbow joint instability in valgus and varus...

Determinants of the quality of brazed joints of nickel-based superalloys

Directory of Open Access Journals (Sweden)

Katarzyna Strzelczak

2017-10-01

Full Text Available In the aerospace industry, passenger safety depends on proper quality control at each production stage. The main responsibility for the correct operation of the aircraft lies within a gas turbine. A proper and rigorous selection of the gas turbine construction material is required, and in a further step, the method of joining the construction parts. Nickel superalloys due to the high heat resistance, strength and creep resistance at high temperatures, toughness and corrosion resistance, are very often used for the construction of a gas turbine engine. In the next step, the selection of joining method is necessary. This method must be able to achieve high-quality connections, resistant to work at high temperatures and corrosive environments. The most effective bonding method that meets the above conditions is brazing. In this study non-destructive (visual test and destructive (metallographic test of brazed joint of Inconel 718 and Inconel 625 were conducted.

Comprehensive Joint Feedback Control for Standing by Functional Neuromuscular Stimulation – a Simulation Study

Science.gov (United States)

Nataraj, Raviraj; Audu, Musa L.; Kirsch, Robert F.; Triolo, Ronald J.

2013-01-01

Previous investigations of feedback control of standing after spinal cord injury (SCI) using functional neuromuscular stimulation (FNS) have primarily targeted individual joints. This study assesses the potential efficacy of comprehensive (trunk, hips, knees, and ankles) joint-feedback control against postural disturbances using a bipedal, three-dimensional computer model of SCI stance. Proportional-derivative feedback drove an artificial neural network trained to produce muscle excitation patterns consistent with maximal joint stiffness values achievable about neutral stance given typical SCI muscle properties. Feedback gains were optimized to minimize upper extremity (UE) loading required to stabilize against disturbances. Compared to the baseline case of maximum constant muscle excitations used clinically, the controller reduced UE loading by 55% in resisting external force perturbations and by 84% during simulated one-arm functional tasks. Performance was most sensitive to inaccurate measurements of ankle plantar/dorsiflexion position and hip ab/adduction velocity feedback. In conclusion, comprehensive joint-feedback demonstrates potential to markedly improve FNS standing function. However, alternative control structures capable of effective performance with fewer sensor-based feedback parameters may better facilitate clinical usage. PMID:20923741

Joint angles of the ankle, knee, and hip and loading conditions during split squats.

Science.gov (United States)

Schütz, Pascal; List, Renate; Zemp, Roland; Schellenberg, Florian; Taylor, William R; Lorenzetti, Silvio

2014-06-01

The aim of this study was to quantify how step length and the front tibia angle influence joint angles and loading conditions during the split squat exercise. Eleven subjects performed split squats with an additional load of 25% body weight applied using a barbell. Each subject's movements were recorded using a motion capture system, and the ground reaction force was measured under each foot. The joint angles and loading conditions were calculated using a cluster-based kinematic approach and inverse dynamics modeling respectively. Increases in the tibia angle resulted in a smaller range of motion (ROM) of the front knee and a larger ROM of the rear knee and hip. The external flexion moment in the front knee/hip and the external extension moment in the rear hip decreased as the tibia angle increased. The flexion moment in the rear knee increased as the tibia angle increased. The load distribution between the legs changed squat execution was varied. Our results describing the changes in joint angles and the resulting differences in the moments of the knee and hip will allow coaches and therapists to adapt the split squat exercise to the individual motion and load demands of athletes.

Microstructure and mechanical properties of similar and dissimilar joints of aluminium alloy and pure copper by friction stir welding

Directory of Open Access Journals (Sweden)

V.C. Sinha

2016-09-01

Full Text Available In the present study, the microstructure and mechanical properties of similar and dissimilar friction stir welded joints of aluminium alloy (AlA and pure copper (Cu were evaluated at variable tool rotational speeds from 150 to 900 rpm in steps of 150 rpm at 60 mm/min travel speed and constant tilt angle 2°. The interfacial microstructures of the joints were characterised by optical and scanning electron microscopy. The Al4Cu9, AlCu, Al2Cu and Al2Cu3 intermetallic compounds have been observed at the interface and stir zone region of dissimilar Al/Cu FSWed joints. Variation in the grain size was observed in the stir zone depending upon the heat input value. Axial force, traverse force and torque value were analysed with variation in tool rotational speed. Residual stresses were measured at the stir zone by X-ray diffraction technique. Maximum ultimate tensile strength of ∼75% of AlA strength for AlA–AlA joints has been obtained at 750 rpm and for Cu–Cu joint tensile strength of ∼100% of tensile strength of Cu was obtained at 300 rpm. However, for Cu–AlA joint when processed at 600 rpm tool rotational speed achieved maximum ultimate tensile strength of ∼77% of AlA.

Modified Design of Pin-on-Ring Tribometer for Hip Joint Prostheses Measurement; Case Study on Salat Activity

Directory of Open Access Journals (Sweden)

Muhammad Khafidh

2015-02-01

Full Text Available Total hip replacement (THR is one of the most successful orthopedic surgical procedures for replacing a broken hip joint. In THR, wear may occur at the articulating surface of the acetabular cup and the femoral head. In Indonesia, the country with the largest Muslim population in the world, most of the inhabitants do salat (praying every day. THR users are banned from doing salat for fear it will damage the hip joint prostheses. The previous wear calculation methods on the hip joint prostheses use the gravimetric, coordinate measuring machine (CMM, profiler, and geometric method. The disadvantages of the previous methods are that the geometry of the wear patch and the wear volume are only known at the end of the experiment, so they cannot be used to calculate the specific wear rate values in real time. So far, in every modeling of the hip joint prostheses, the values of the specific wear rate are assumed to be constant. This paper reports on the design modification of a pin-on-ring tribometer that is used to measure the wear volumes in hip joint prostheses. The result shows that modifications of the femoral head holder, reciprocating motion, elastic joint, and extra displacement transducer is needed to get the specific wear rate value. The calculation method to find the delta volume that is the value of displacement less than the displacement minimum (δmin is based on a graph, while the calculation method to find the delta volume that is the value of displacement that is more than the displacement minimum (δmin is based on an equation. In the salat test protocol, the longest test time was during the sujud (prostration motion, which took 1034.17 minutes in the experiment.

Optimally Joint Subcarrier Matching and Power Allocation in OFDM Multihop System

Directory of Open Access Journals (Sweden)

Shuyuan Yang

2008-04-01

Full Text Available Orthogonal frequency division multiplexing (OFDM multihop system is a promising way to increase capacity and coverage. In this paper, we propose an optimally joint subcarrier matching and power allocation scheme to further maximize the total channel capacity with the constrained total system power. First, the problem is formulated as a mixed binary integer programming problem, which is prohibitive to find the global optimum in terms of complexity. Second, by making use of the equivalent channel power gain for any matched subcarrier pair, a low complexity scheme is proposed. The optimal subcarrier matching is to match subcarriers by the order of the channel power gains. The optimal power allocation among the matched subcarrier pairs is water-filling. An analytical argument is given to prove that the two steps achieve the optimally joint subcarrier matching and power allocation. The simulation results show that the proposed scheme achieves the largest total channel capacity as compared to the other schemes, where there is no subcarrier matching or no power allocation.

Optimally Joint Subcarrier Matching and Power Allocation in OFDM Multihop System

Directory of Open Access Journals (Sweden)

Wang Wenyi

2008-01-01

Full Text Available Orthogonal frequency division multiplexing (OFDM multihop system is a promising way to increase capacity and coverage. In this paper, we propose an optimally joint subcarrier matching and power allocation scheme to further maximize the total channel capacity with the constrained total system power. First, the problem is formulated as a mixed binary integer programming problem, which is prohibitive to find the global optimum in terms of complexity. Second, by making use of the equivalent channel power gain for any matched subcarrier pair, a low complexity scheme is proposed. The optimal subcarrier matching is to match subcarriers by the order of the channel power gains. The optimal power allocation among the matched subcarrier pairs is water-filling. An analytical argument is given to prove that the two steps achieve the optimally joint subcarrier matching and power allocation. The simulation results show that the proposed scheme achieves the largest total channel capacity as compared to the other schemes, where there is no subcarrier matching or no power allocation.

High resolution ultrasonography in ankle joint pain: Where does it stand?

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Mennatallah Hatem Shalaby

2017-09-01

Full Text Available Background: The ankle is frequently injured in trauma, overuse syndrome and inflammatory processes. Different imaging modalities assess the ankle, including plain radiography, computed tomography (CT, magnetic resonance imaging (MRI, and ultrasonography (US. Purpose: Our objective is to assess the role of high resolution US as a valuable tool in the depiction of causes of ankle joint pain. Patients and methods: The study included 28 patients presented with ankle pain ranging in age from 17 to 60 years. They were examined by US and findings were correlated with MRI. Results: US was capable to detect various lesions (synovitis, arthritis, plantar fasciitis, tendon and ligamentous lesions. It had a sensitivity of 95.4%, a specificity of 83.3% and an overall accuracy of 92.8%. US had a limited value in detection of avascular necrosis (AVN, bone marrow oedema and fractures. Conclusion: US can be used as a first step diagnostic tool in cases of ankle pain. MRI should be spared to cases with negative or equivocal US findings. Keywords: High resolution ultrasound, Ankle joint pain, Tendons, Ligaments, Synovitis, Arthritis

Joint adaptive modulation and diversity combining with feedback error compensation

KAUST Repository

Choi, Seyeong; Hong-Chuan, Yang; Alouini, Mohamed-Slim; Qaraqe, Khalid A.

2009-01-01

This letter investigates the effect of feedback error on the performance of the joint adaptive modulation and diversity combining (AMDC) scheme which was previously studied with an assumption of error-free feedback channels. We also propose to utilize adaptive diversity to compensate for the performance degradation due to feedback error. We accurately quantify the performance of the joint AMDC scheme in the presence of feedback error, in terms of the average number of combined paths, the average spectral efficiency, and the average bit error rate. Selected numerical examples are presented and discussed to illustrate the effectiveness of the proposed feedback error compensation strategy with adaptive combining. It is observed that the proposed compensation strategy can offer considerable error performance improvement with little loss in processing power and spectral efficiency in comparison with the no compensation case. Copyright © 2009 IEEE.

Joint adaptive modulation and diversity combining with feedback error compensation

KAUST Repository

Choi, Seyeong

2009-11-01

This letter investigates the effect of feedback error on the performance of the joint adaptive modulation and diversity combining (AMDC) scheme which was previously studied with an assumption of error-free feedback channels. We also propose to utilize adaptive diversity to compensate for the performance degradation due to feedback error. We accurately quantify the performance of the joint AMDC scheme in the presence of feedback error, in terms of the average number of combined paths, the average spectral efficiency, and the average bit error rate. Selected numerical examples are presented and discussed to illustrate the effectiveness of the proposed feedback error compensation strategy with adaptive combining. It is observed that the proposed compensation strategy can offer considerable error performance improvement with little loss in processing power and spectral efficiency in comparison with the no compensation case. Copyright © 2009 IEEE.

The friction coefficient of shoulder joints remains remarkably low over 24 h of loading.

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Jones, Brian K; Durney, Krista M; Hung, Clark T; Ateshian, Gerard A

2015-11-05

The frictional response of whole human joints over durations spanning activities of daily living has not been reported previously. This study measured the friction of human glenohumeral joints during 24 h of reciprocal loading in a pendulum testing device, at moderate (0.2 mm/s, 4320 cycles) and low (0.02 mm/s, 432 cycles) sliding speeds, under a 200 N load. The effect of joint congruence was also investigated by testing human humeral heads against significantly larger mature bovine glenoids. Eight human joints and six bovine joints were tested in four combinations: human joints tested at moderate (hHCMS, n=6) and low speed (hHCLS, n=3), human humeral heads tested against bovine glenoids at moderate speed (LCMS, n=3), and bovine joints tested at moderate speed (bHCMS, n=3). In the first half hour the mean±standard deviation of the friction coefficient was hHCMS: 0.0016±0.0011, hHCLS: 0.0012±0.0002, LCMS: 0.0008±0.0002 and bHCMS: 0.0024±0.0008; in the last four hours it was hHCMS: 0.0057±0.0025, hHCLS: 0.0047±0.0017, LCMS: 0.0012±0.0003 and bHCMS: 0.0056±0.0016. The initial value was lower than the final value (pfriction coefficient of natural human shoulders remains remarkably low (averaging as little as 0.0015 and no greater than 0.006) for up to 24 h of continuous loading. The sustained low friction coefficients observed in incongruent joints (~0.001) likely represent rolling rather than sliding friction. Copyright © 2015. Published by Elsevier Ltd.

The Friction Coefficient of Shoulder Joints Remains Remarkably Low Over 24 h of Loading

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Jones, Brian K.; Durney, Krista M.; Hung, Clark T.; Ateshian, Gerard A.

2015-01-01

The frictional response of whole human joints over durations spanning activities of daily living has not been reported previously. This study measured the friction of human glenohumeral joints during 24 h of reciprocal loading in a pendulum testing device, at moderate (0.2 mm/s, 4320 cycles) and low (0.02 mm/s, 432 cycles) sliding speeds, under a 200 N load. The effect of joint congruence was also investigated by testing human humeral heads against significantly larger mature bovine glenoids. Six human joints and six bovine joints were tested in four combinations: human joints tested at moderate (hHCMS, n=6) and low speed (hHCLS, n=3), human humeral heads tested against bovine glenoids at moderate speed (LCMS, n=3), and bovine joints tested at moderate speed (bHCMS, n=3). In the first half hour the mean ± standard deviation of the friction coefficient was hHCMS: 0.0016±0.0011, hHCLS: 0.0012±0.0002, LCMS: 0.0008±0.0002 and bHCMS: 0.0024±0.0008; in the last four hours it was hHCMS: 0.0057±0.0025, hHCLS: 0.0047±0.0017, LCMS: 0.0012±0.0003 and bHCMS: 0.0056±0.0016. The initial value was lower than the final value (pfriction coefficient of natural human shoulders remains remarkably low (averaging as little as 0.0015 and no greater than 0.006) for up to 24 h of continuous loading. The sustained low friction coefficients observed in incongruent joints (~0.001) likely represent rolling rather than sliding friction. PMID:26472306

The Effect of Step Frequency Training on a Male Runner with Patellofemoral Pain

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Shelley Payne

2016-10-01

Full Text Available Running is a very popular form of exercise. The most common site of injury for runners is the knee with patellofemoral pain being the most common complaint. Patellofemoral pain is described as pain around the patella that is worse with activities such as running, squatting, ascending or descending stairs, or sitting for long periods. Much of the recent work with the treatment of patellofemoral pain has involved strengthening of the hip musculature to reduce pain about the knee. However, the ability of these strengthening programs to change lower extremity mechanics or sustain long-term pain reduction has been unproven. More recently, researchers have started to examine the impact of step frequency modification on the forces encountered in the lower extremity, and specifically about the patellofemoral joint. The purpose of this study was to examine the short term effects of step frequency training in a recreational runner with PFP. Methods: This was a single-subject case study design. The subject completed a pre- and post-training assessment to determine the preferred step frequency. The subject also completed a Visual Analog Scale (VAS and a Lower Extremity Functional Scale (LEFS. Results: After the initial evaluation, the subject completed training 2 times per week for 4 weeks using auditory feedback to increase their step frequency by 5% above their preferred step frequency. The subject experienced a decrease in pain as measured by the VAS and an increase in function as measured by the LEFS across the 4 week training. Discussion: Although the results of this case study may not be generalized, the positive findings support additional research to determine both the short and long-term effects of step frequency training on PFP.

The Joint Force Air Component Commander and the Integration of Offensive Cyberspace Effects: Power Projection through Cyberspace

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2016-06-14

in theory . Offensive cyberspace operations have the potential to provide these types of power- projecting effects in the battlespace, but how can...approach to allow for the maturation of command relationships, authorities, and buildup of operational capacity. In the direct support model...send cyber- space liaisons to the air component to integrate joint cyberspace operations. A major step in the center’s maturation process is

A cadaveric investigation into the demographic and bony alignment properties associated with osteoarthritis of the patellofemoral joint.

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Weinberg, Douglas S; Tucker, Braden J; Drain, Joseph P; Wang, David M; Gilmore, Allison; Liu, Raymond W

2016-06-01

Patellofemoral joint osteoarthritis is common, although circumstances dictating its evolution and pathogenesis remain unclear. Advances in surgical technique have improved the ability to modify long-bone alignment in the coronal, sagittal, and axial planes. However, to our knowledge, there is no significant long-term data available in regard to the relationship between anatomic alignment parameters most amenable to surgical modification and patellofemoral joint osteoarthritis. Five-hundred and seventy-one cadaveric skeletons were obtained from the Hamann-Todd osteological collection. Mechanical lateral distal femoral angle, medial proximal tibial angle, tibial slope, femoral version, tibial torsion, the position of the tibial tubercle relative to the width of the tibial plateau, trochlear depth, and patellar size were measured using validated techniques. A previously published grading system for patellofemoral joint arthritis was used to quantify macroscopic signs of degenerative joint disease. Increasing age (standardized beta 0.532, ppatellofemoral joint osteoarthritis. A relatively more laterally positioned tibial tubercle trended towards predicting patellofemoral joint osteoarthritis (standardized beta 0.080, p=0.089). These findings confirm that patellofemoral joint osteoarthritis is strongly associated with increasing age and female gender. Valgus alignment of the distal femur, a relatively more lateral location of the tibial tubercle, and a shallower trochlear grove appear to have modest effects on the development of patellofemoral joint osteoarthritis. Copyright © 2016 Elsevier B.V. All rights reserved.

CT-Guided Percutaneous Step-by-Step Radiofrequency Ablation for the Treatment of Carcinoma in the Caudate Lobe

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Dong, Jun; Li, Wang; Zeng, Qi; Li, Sheng; Gong, Xiao; Shen, Lujun; Mao, Siyue; Dong, Annan; Wu, Peihong

2015-01-01

Abstract The location of the caudate lobe and its complex anatomy make caudate lobectomy and radiofrequency ablation (RFA) under ultrasound guidance technically challenging. The objective of the exploratory study was to introduce a novel modality of treatment of lesions in caudate lobe and discuss all details with our experiences to make this novel treatment modality repeatable and educational. The study enrolled 39 patients with liver caudate lobe tumor first diagnosed by computerized tomography (CT) or magnetic resonance imaging (MRI). After consultation of multi-disciplinary team, 7 patients with hepatic caudate lobe lesions were enrolled and accepted CT-guided percutaneous step-by-step RFA treatment. A total of 8 caudate lobe lesions of the 7 patients were treated by RFA in 6 cases and RFA combined with percutaneous ethanol injection (PEI) in 1 case. Median tumor diameter was 29 mm (range, 18–69 mm). A right approach was selected for 6 patients and a dorsal approach for 1 patient. Median operative time was 64 min (range, 59–102 min). Median blood loss was 10 mL (range, 8-16 mL) and mainly due to puncture injury. Median hospitalization time was 4 days (range, 2–5 days). All lesions were completely ablated (8/8; 100%) and no recurrence at the site of previous RFA was observed during median 8 months follow-up (range 3–11 months). No major or life-threatening complications or deaths occurred. In conclusion, percutaneous step-by-step RFA under CT guidance is a novel and effective minimally invasive therapy for hepatic caudate lobe lesions with well repeatability. PMID:26426638

Joint Rhythmic Movement Increases 4-Year-Old Children's Prosocial Sharing and Fairness Toward Peers.

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Rabinowitch, Tal-Chen; Meltzoff, Andrew N

2017-01-01

The allocation of resources to a peer partner is a prosocial act that is of fundamental importance. Joint rhythmic movement, such as occurs during musical interaction, can induce positive social experiences, which may play a role in developing and enhancing young children's prosocial skills. Here, we investigated whether joint rhythmic movement, free of musical context, increases 4-year-olds' sharing and sense of fairness in a resource allocation task involving peers. We developed a precise procedure for administering joint synchronous experience, joint asynchronous experience, and a baseline control involving no treatment. Then we tested how participants allocated resources between self and peer. We found an increase in the generous allocation of resources to peers following both synchronous and asynchronous movement compared to no treatment. At a more theoretical level, this result is considered in relation to previous work testing other aspects of child prosociality, for example, peer cooperation, which can be distinguished from judgments of fairness in resource allocation tasks. We draw a conceptual distinction between two types of prosocial behavior: resource allocation (an other-directed individual behavior) and cooperation (a goal-directed collaborative endeavor). Our results highlight how rhythmic interactions, which are prominent in joint musical engagements and synchronized activity, influence prosocial behavior between preschool peers.

Increase in Leg Stiffness Reduces Joint Work During Backpack Carriage Running at Slow Velocities.

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Liew, Bernard; Netto, Kevin; Morris, Susan

2017-10-01

Optimal tuning of leg stiffness has been associated with better running economy. Running with a load is energetically expensive, which could have a significant impact on athletic performance where backpack carriage is involved. The purpose of this study was to investigate the impact of load magnitude and velocity on leg stiffness. We also explored the relationship between leg stiffness and running joint work. Thirty-one healthy participants ran overground at 3 velocities (3.0, 4.0, 5.0 m·s -1 ), whilst carrying 3 load magnitudes (0%, 10%, 20% weight). Leg stiffness was derived using the direct kinetic-kinematic method. Joint work data was previously reported in a separate study. Linear models were used to establish relationships between leg stiffness and load magnitude, velocity, and joint work. Our results found that leg stiffness did not increase with load magnitude. Increased leg stiffness was associated with reduced total joint work at 3.0 m·s -1 , but not at faster velocities. The association between leg stiffness and joint work at slower velocities could be due to an optimal covariation between skeletal and muscular components of leg stiffness, and limb attack angle. When running at a relatively comfortable velocity, greater leg stiffness may reflect a more energy efficient running pattern.

Medial Elbow Joint Space Increases With Valgus Stress and Decreases When Cued to Perform A Maximal Grip Contraction.

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Pexa, Brett S; Ryan, Eric D; Myers, Joseph B

2018-04-01

Previous research indicates that the amount of valgus torque placed on the elbow joint during overhead throwing is higher than the medial ulnar collateral ligament (UCL) can tolerate. Wrist and finger flexor muscle activity is hypothesized to make up for this difference, and in vitro studies that simulated activity of upper extremity musculature, specifically the flexor digitorum superficialis and flexor carpi ulnaris, support this hypothesis. To assess the medial elbow joint space at rest, under valgus stress, and under valgus stress with finger and forearm flexor contraction by use of ultrasonography in vivo. Controlled laboratory study. Participants were 22 healthy males with no history of elbow dislocation or UCL injury (age, 21.25 ± 1.58 years; height, 1.80 ± 0.08 m; weight, 79.43 ± 18.50 kg). Medial elbow joint space was measured by use of ultrasonography during 3 separate conditions: at rest (unloaded), under valgus load (loaded), and with a maximal grip contraction under a valgus load (loaded-contracted) in both limbs. Participants lay supine with their arm abducted 90° and elbow flexed 30° with the forearm in full supination. A handgrip dynamometer was placed in the participants' hand to grip against during the contracted condition. Images were reduced in ImageJ to assess medial elbow joint space. A 2-way (condition × limb) repeated-measures analysis of variance and Cohen's d effect sizes were used to assess changes in medial elbow joint space. Post hoc testing was performed with a Bonferroni adjustment to assess changes within limb and condition. The medial elbow joint space was significantly larger in the loaded condition (4.91 ± 1.16 mm) compared with the unloaded condition (4.26 ± 1.23 mm, P space increases under a valgus load and then decreases when a maximal grip contraction is performed. This indicates that wrist and finger flexor muscle contraction may assist in limiting medial elbow joint space, a result similar to findings of previous

Experimental characterization and numerical simulation of riveted lap-shear joints using Rivet Element

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Vivio, Francesco; Fanelli, Pierluigi; Ferracci, Michele

2018-03-01

In aeronautical and automotive industries the use of rivets for applications requiring several joining points is now very common. In spite of a very simple shape, a riveted junction has many contact surfaces and stress concentrations that make the local stiffness very difficult to be calculated. To overcome this difficulty, commonly finite element models with very dense meshes are performed for single joint analysis because the accuracy is crucial for a correct structural analysis. Anyhow, when several riveted joints are present, the simulation becomes computationally too heavy and usually significant restrictions to joint modelling are introduced, sacrificing the accuracy of local stiffness evaluation. In this paper, we tested the accuracy of a rivet finite element presented in previous works by the authors. The structural behaviour of a lap joint specimen with a rivet joining is simulated numerically and compared to experimental measurements. The Rivet Element, based on a closed-form solution of a reference theoretical model of the rivet joint, simulates local and overall stiffness of the junction combining high accuracy with low degrees of freedom contribution. In this paper the Rivet Element performances are compared to that of a FE non-linear model of the rivet, built with solid elements and dense mesh, and to experimental data. The promising results reported allow to consider the Rivet Element able to simulate, with a great accuracy, actual structures with several rivet connections.

Joint hyperlaxity prevents relapses in clubfeet treated by Ponseti method-preliminary results.

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Cosma, Dan Ionuţ; Corbu, Andrei; Nistor, Dan Viorel; Todor, Adrian; Valeanu, Madalina; Morcuende, Jose; Man, Sorin

2018-05-07

The aim of the study was to evaluate the role of joint hyperlaxity (by Beighton score) as a protective factor for clubfoot relapse. Patients with idiopathic clubfoot treated with the Ponseti method between January 2004 and December 2012, without other congenital foot deformity, and not previously treated by open surgery were included in either the Relapse group (n = 23) if it was a clubfoot relapse or the Control group (n = 19) if no relapse was noted. Joint laxity was evaluated using the Beighton score at the latest follow-up against the Normal group (n = 22, children matched by sex and age without clubfoot deformity). We found a significantly higher joint laxity in the Control group (4.58, 95% confidence interval [CI]: 2.1-7.06) as compared to the Relapse (3.17, 95% CI: 1.53-4.81, p = 0.032) and Normal (3.14, 95% CI: 1.78-4.5, p = 0.03) groups. The univariate logistic regression showed a 5.28-times increase in the risk of relapse for a Beighton score lower than 4/9 points (odds ratio = 5.28; 95% CI = 1.29-21.5; p = 0.018). Joint hyperlaxity could be a protective factor for clubfoot relapse.

Comparison of crossover and jab step start techniques for base stealing in baseball.

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Miyanishi, Tomohisa; Endo, So; Nagahara, Ryu

2017-11-01

Base stealing is an important tactic for increasing the chance of scoring in baseball. This study aimed to compare the crossover step (CS) and jab step (JS) starts for base stealing start performance and to clarify the differences between CS and JS starts in terms of three-dimensional lower extremity joint kinetics. Twelve male baseball players performed CS and JS starts, during which their motion and the force they applied to the ground were simultaneously recorded using a motion-capture system and two force platforms. The results showed that the normalised average forward external power, the average forward-backward force exerted by the left leg, and the forward velocities of the whole body centre of gravity generated by both legs and the left leg were significantly higher for the JS start than for the CS start. Moreover, the positive work done by hip extension during the left leg push-off was two-times greater for the JS start than the CS start. In conclusion, this study has demonstrated that the jab step start may be the better technique for a base stealing start and that greater positive work produced by left hip extension is probably responsible for producing its larger forward ground reaction force.

Delivering stepped care: an analysis of implementation in routine practice

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Richards David A

2012-01-01

Full Text Available Abstract Background In the United Kingdom, clinical guidelines recommend that services for depression and anxiety should be structured around a stepped care model, where patients receive treatment at different 'steps,' with the intensity of treatment (i.e., the amount and type increasing at each step if they fail to benefit at previous steps. There are very limited data available on the implementation of this model, particularly on the intensity of psychological treatment at each step. Our objective was to describe patient pathways through stepped care services and the impact of this on patient flow and management. Methods We recorded service design features of four National Health Service sites implementing stepped care (e.g., the types of treatments available and their links with other treatments, together with the actual treatments received by individual patients and their transitions between different treatment steps. We computed the proportions of patients accessing, receiving, and transiting between the various steps and mapped these proportions visually to illustrate patient movement. Results We collected throughput data on 7,698 patients referred. Patient pathways were highly complex and very variable within and between sites. The ratio of low (e.g., self-help to high-intensity (e.g., cognitive behaviour therapy treatments delivered varied between sites from 22:1, through 2.1:1, 1.4:1 to 0.5:1. The numbers of patients allocated directly to high-intensity treatment varied from 3% to 45%. Rates of stepping up from low-intensity treatment to high-intensity treatment were less than 10%. Conclusions When services attempt to implement the recommendation for stepped care in the National Institute for Health and Clinical Excellence guidelines, there were significant differences in implementation and consequent high levels of variation in patient pathways. Evaluations driven by the principles of implementation science (such as targeted planning

The efficacy of negative pressure wound therapy in treating sacroiliac joint tuberculosis with a chronic sinus tract: a case series.

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Luo, Xiaobo; Tang, Xiangyu; Ma, Yuanzheng; Zhang, Yonggang; Fang, Shuzhi

2015-08-06

Tuberculous sacroiliitis with abscess accounts for approximately 50 % of all sacroiliac joint tuberculosis cases. Tuberculous abscesses spread into the sacroiliac joint capsule, subcutaneous tissue, and the skin, and finally becomes a skin sinus. As there are no previous reports about sacroiliac joint tuberculosis with a chronic sinus, we evaluated its clinical characteristics and management by negative pressure wound therapy. A retrospective analysis of 12 patients with sacroiliac joint tuberculosis with chronic sinuses treated between January 2005 and January 2010 was conducted. Patients were treated with negative pressure wound therapy (NPWT). Treatment was divided into three phases: control phase, standard dressing changes daily for 4 weeks; interphase washout period, dressing changes every 3 days for 1 week; and intervention phase, no dressing changes until minimal sinus tract drainage (sacroiliac joint tuberculosis with a chronic sinus can be difficult. NPWT provides better healing of sacroiliac joint tuberculosis with a chronic sinus than standard dressing changes.

Depression and the Overall Burden of Painful Joints: An Examination among Individuals Undergoing Hip and Knee Replacement for Osteoarthritis

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Rajiv Gandhi

2015-01-01

Full Text Available The majority of patients with hip or knee osteoarthritis (OA report one or more symptomatic joints apart from the one targeted for surgical care. Therefore, the purpose of the present study was to investigate the association between the burden of multiple symptomatic joints and self-reported depression in patients awaiting joint replacement for OA. Four hundred and seventy-five patients at a single centre were evaluated. Patients self-reported joints that were painful and/or symptomatic most days of the previous month on a homunculus, with nearly one-third of the sample reporting 6 or more painful joints. The prevalence of depression was 12.2% (58/475. When adjusted for age, sex, education level, hip or knee OA, body mass index, chronic condition count, and joint-specific WOMAC scores, each additional symptomatic joint was associated with a 19% increased odds (odds ratio: 1.19 (95% CI: 1.08, 1.31, P<0.01 of self-reported depression. Individuals reporting 6 or more painful joints had 2.5-fold or greater odds of depression when compared to those patients whose symptoms were limited to the surgical joint. A focus on the surgical joint alone is likely to miss a potentially important determinant of postsurgical patient-reported outcomes in patients undergoing hip or knee replacement.

The Joint Philosophical Program of Russell and Wittgenstein and Its Demise

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Nikolay Milkov

2013-03-01

Full Text Available Between April and November 1912, Bertrand Russell and Ludwig Wittgenstein were engaged in a joint philosophical program. Wittgenstein’s meeting with Gottlob Frege in December 1912 led, however, to its dissolution—the joint program was abandoned. Section 1 of this paper outlines the key points of that program, identifying what Russell and Wittgenstein each contributed to it. The second section determines precisely those features of their collaborative work that Frege criticized. Finally, building upon the evidence developed in the first two sections, section 3 recasts along previously undeveloped lines Wittgensein’s logical–philosophical discoveries in the two years following his encounter with Frege in 1912. The paper concludes, in section 4, with an overview of the dramatic consequences the Frege–Wittgenstein critique had for Russell’s philosophical development.

A single-step method for rapid extraction of total lipids from green microalgae.

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Martin Axelsson

Full Text Available Microalgae produce a wide range of lipid compounds of potential commercial interest. Total lipid extraction performed by conventional extraction methods, relying on the chloroform-methanol solvent system are too laborious and time consuming for screening large numbers of samples. In this study, three previous extraction methods devised by Folch et al. (1957, Bligh and Dyer (1959 and Selstam and Öquist (1985 were compared and a faster single-step procedure was developed for extraction of total lipids from green microalgae. In the single-step procedure, 8 ml of a 2∶1 chloroform-methanol (v/v mixture was added to fresh or frozen microalgal paste or pulverized dry algal biomass contained in a glass centrifuge tube. The biomass was manually suspended by vigorously shaking the tube for a few seconds and 2 ml of a 0.73% NaCl water solution was added. Phase separation was facilitated by 2 min of centrifugation at 350 g and the lower phase was recovered for analysis. An uncharacterized microalgal polyculture and the green microalgae Scenedesmus dimorphus, Selenastrum minutum, and Chlorella protothecoides were subjected to the different extraction methods and various techniques of biomass homogenization. The less labour intensive single-step procedure presented here allowed simultaneous recovery of total lipid extracts from multiple samples of green microalgae with quantitative yields and fatty acid profiles comparable to those of the previous methods. While the single-step procedure is highly correlated in lipid extractability (r² = 0.985 to the previous method of Folch et al. (1957, it allowed at least five times higher sample throughput.

About the Joint Chiefs of Staff

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Skip to main content (Press Enter). Toggle navigation Joint Chiefs of Staff Joint Chiefs of Staff Joint Chiefs of Staff Facebook Twitter YouTube Flickr Blog Instagram Search JCS: Search Search Search JCS: Search Home Media News Photos Videos Publications About The Joint Staff Chairman Vice Chairman