Previous research proposed a method using interpolation of the joint angles in key frames extracted from a field-survey video to estimate the dynamic L5/S1 joint loading for symmetric lifting tasks. The advantage of this method is that there is no need to use unwieldy equipment for capturing full body movement for ...

STUDY DESIGN.: A retrospective clinical and radiographic study was performed. OBJECTIVE.: The purpose of this study was to compare outcomes of patients with degenerative spondylolisthesis and a preexisting degenerative L5-S1 disc treated with a lumbar floating fusion (LFF) versus lumbosacral fusion (LSF). SUMMARY ...

Total disc replacement and posterior dynamic stabilization represent alternatives to lumbar spinal fusion which should reduce the risk of adjacent segment degeneration. Disc replacement is indicated for pure discopathy without facet joint degeneration. Spinopelvic balance influences the implant's biomechanics. Therefore pelvic incidence, sacral slope, ...

The aim of this study was to introduce a Newton-Euler inverse dynamics model that included reaction force and moment estimation at the lumbo-sacral (L5-S1) and thoraco-lumbar (T12-L1) joints. Data were collected while participants ran over ground at 3.8 m x s(-1) at three different stride lengths: preferred stride ...

Herniated intervertebral disc causes in a great number of cases of lumbar nerve root compression, especially in the segment L5/S1. Other reasons responsible for stress to the lumbar spinal root are the spinal canal stenosis and the postdiscotomy syndrome. For patients without neurological ...

STUDY DESIGN.: The study aims to investigate the dimensions and angular orientations of the pedicles of the first sacral segment at the L5-S1 junctions affected by transitional variations. OBJECTIVE.: Measurement of parameters of the S1 pedicle and its orientation in sacra with (1) Accessory ...

One thousand and thirty patients with proved L(5)/S(1)disc herniations were examined. The dynamics of disease in acute stage was studied using ultrasonography and electromyography in 3 groups of patients: 280 with lumboischialgia, 520 with the root syndrome and 230 controls without back pain. It has been shown that ...

Afferent inputs are known to modulate the activity of locomotor central pattern generators, but their role in the generation of locomotor patterns remains uncertain. This study sought to investigate the importance of afferent input for producing bilateral, coordinated hindlimb stepping in adult cats. Following complete spinal transection, animals were trained to step on the moving belt of a ...

ABSTRACT: Study Design: An anatomic study of sacral inclination, pelvic incidence, pelvic lordosis, and disc degeneration in cadaveric lumbar spines.Objective: To evaluate the relationship between sacropelvic parameters and disc degeneration in subjects with bilateral spondylolysis at L5.Summary of Background Data: ...

Low-back pain is a common, disabling medical condition, and one of the major causes is disc degeneration. Total disc replacements are intended to treat back pain by restoring disc height and re-establishing functional motion and stability at the index level. The objective of this study was to determine the effect on range of motion (ROM) and stiffness after implantation of the ProDisc�-L device ...

Mechanical loading of the low back during lifting is a common cause of low back pain. In this study two-handed lifting is compared to one-handed lifting (with and without supporting the upper body with the free hand) while lifting over an obstacle. A 3-D linked segment model was combined with an EMG-assisted trunk muscle model to quantify kinematics and joint loads at the L5S1 ...

We describe a novel technique for preparing a fibular allograft for use as a transsacral strut with an anterior cruciate ligament (ACL) coring reamer for stabilization of high-grade spondylolisthesis deformities involving the L5--S1 segment in conjunction with instrumented posterolateral fusions. Over 4 years, 6 patients underwent instrumented posterolateral fusions from L3 or ...

This study examined errors introduced by a posture matching approach (3DMatch) relative to dynamic three-dimensional rigid link and EMG-assisted models. Eighty-eight lifting trials of various combinations of heights (floor, 0.67, 1.2�m), asymmetry (left, right and center) and mass (7.6 and 9.7�kg) were videotaped while spine postures, ground reaction forces, segment ...

To find out whether segmental magnetic resonance imaging (MRI) findings such as intervertebral disc degeneration (DD) and facet joint osteoarthritis (FJO) are associated with motion deficiencies as seen in common mobility tests and observed range of motion (ROM). A total of 112 female subjects, nurses and office workers, with and without low back pain, were examined by ...

ObjectiveA minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) has recently been introduced. However, MIS TLIF is a technically challenging procedure. The authors performed retrospective analysis about MIS TLIF using a single interbody cage.MethodsTwenty-eight consecutive patients were treated by MIS TLIF. Of these 28 patients, 20 patients were included in this retrospective ...

The three-dimensional load displacement behavior of nine fresh adult L5-S1 spine motion segments was studied. Static test forces up to 160 N in anterior, posterior, and lateral shear, test forces up to 320 N in compression, and test moments up to 15.7 Nm in flexion, extension, lateral bending, ...

BS>A device is descrined for producing nuclear fusion reactions by additional acceleration of a hydrogen isotope plasma formed and initially accelerated by a collapsing magnetic field. The plasma is enclosed in a toroidal cavity within a vessel composed of a plurality of insulated coaxial segments. The added ...

These documents describe the assembly and alignment of the typical accelerator 40-foot segments of the Stanford Linear Accelerator Center's three-kilometer linear accelerator. Required tools and special equipment are listed along with instructions for their use. Tolerances are specified for all phases of ...

... joint loadings, contact forces and segment positions for a 15-segment model of a human body subjected to high accelerations and wind loads. ...

... Accession Number : ADA215836. Title : Biaxial Finite Deformations of Arterial and Benous Segments under Plus or Minus Gz Acceleration Stress. ...

BACKGROUND CONTEXT: Research on lumbosacral transitional vertebra (LSTV) has yielded important information on the structural alterations of the sacrum associated with LSTV. Nevertheless, very little data are available on the relationship of a given type of LSTV with either a typical pattern of sacral morphology or its gender distribution in the population. PURPOSE: To investigate the probable ...

Jul 10, 2002... levitated vehicle, or "bucket," accelerated by a linear synchronous motor. ... segments of accelerating coils on the linear synchronous motor. ...

The Podcast: Inertia and Acceleration is a segment of the Web Seminar: NSTA Press Force and Motion: Stop Faking It! I , December 11, 2008. The pod

The Podcast: Acceleration is a segment of the Force and Motion Short Course. The podcast is 2 minutes 13 seconds in duration. Presented by science experts and NSTA staff, the NSTA Online Short Courses are professional development opportunities de

... To do this the system was considered in the following segments: Electron injection electronics, Electron beam injection hardware, Accelerating ...

A case of late dislocation of a disc spacer L5/S1 with perforation of the sigmoid colon and transanal passage 4�years after implantation is reported. The objective is to describe an uncommon complication of anterior endoscopic spondylodesis ...

Objective:We evaluated our experience with laparoscopic L5-S1 anterior lumbar interbody fusion (ALIF).Methods:This represents a retrospective analysis of consecutive patients who underwent L5-S1 laparoscopic ALIF between February ...

This paper describes the control system of the injector for the LINAC-800 linear electron accelerator. The architecture of the control system, the equipment, and software are presented. This system is part of the first segment of the control system of the LINAC-800 electron accelerator.

Recent developments in spacecraft and high performance aircraft have resulted in the exposure of the human body to the hazards of high accelerations beyond tolerance levels. Circulatory impairment is one of the manifestations of acceleration trauma. A maj...

STUDY DESIGN.: A gross anatomic and magnetic resonance imaging study of intervertebral disc (IVD) degeneration in fresh cadaveric lumbar spines. OBJECTIVE.: The purpose of this study was to find the rate of IVD degeneration. SUMMARY OF BACKGROUND DATA.: Age, sex, race, and lumbar level are among some of the factors that play a role in IVD degeneration. The rate at which IVDs degenerate is unknown. ...

STRUCTURED ABSTRACT: Study Design. A cadaveric biomechanical experiment was conducted to assess the range of motion (ROM) and screw strain at S1 in a long instrumented spinal fusion construct to compare the effects of various surgical strategies for L5-S1 stabilization.Objective. To directly quantify and compare S1 screw strains and lumbosacral ROM for four different L2-S1 posterior ...

Four weeks after an Amanita phalloides poisoning, a 29-year-old man presented an ocular aspergillosis. One month later he developed a bilateral L5-S1 radicular syndrome. The diagnosis of aspergillar spondylodiscities was established on the basis of x-ray, CT-scan, MRI and pathology findings. Clinical and ...

n-l5s1c|-ns A Earle: cf develnpnenta tests were cnnlluctell tn verify tlu anal tica'l. |nu�e1s for the structure and drwa train enahws. llnvieus uere held ...

Variable plasma jet velocity with low beam divergence over a range of mass flow rates can be achieved through segmented electrode operation of Hall plasma accelerator. With the use of just a cathode side electrode at the cathode potential, the beam diverg...

Biomechanical model assumptions affect the interpretation of the role of the muscle or joint moments to the segmental power estimated by induced acceleration analysis (IAA). We evaluated the effect of modeling the pelvis and trunk segments as two separate segments (8 SM) versus as a single ...

This video segment adapted from NOVA shows how the particle accelerator helped physicists find parts of the atom even smaller than protons and neutrons.

Horizontal Gene Transfer (HGT) Greatly Accelerates Genome Evolution and Innovation : ... Gene structure prediction in syntenic DNA segments. ...

This study involved the use of explosively accelerated steel segments (helicopter or other aircraft deliverable to cut trees followed by debris clearance due to overpressure for possible use in Vietnam.

This video segment adapted from NOVA describes a simple experiment that confirmed the idea that microbes can accelerate the biogeochemical process of cave formation.

... most models that describec th it cardiovascular system response to acceleration stress had considered only radia I~slac'~vt5of the vessel wall . ...

In intensity-modulated radiation therapy (IMRT), fluence matrices obtained from a treatment planning system are usually delivered by a linear accelerator equipped with a multileaf collimator (MLC). A segmentation method is needed for decomposing these fluence matrices into segments suitable for the MLC, and the number of ...

The theoretical performance of diagonal conducting wall crossed-field accelerators is examined on the basis of an infinite segmentation assumption using a cross-plane averaged generalized Ohm s law for a partially ionized gas, including ion slip. The desi...

The theoretical performance of diagonal conducting wall crossed field accelerators is examined on the basis of an infinite segmentation assumption using a cross-plane averaged generalized Ohm's law for a partially ionized gas, including ion slip. The desi...

The Department of Energy (DOE) is working to accelerate the acceptance and application of innovative technologies that improve the way the nation manages its environmental remediation problems. The DOE Office of Science and Technology established the Acce...

A method for generating a sequence of intensity-modulated radiation therapy step-and-shoot plans with increasing number of segments is presented. The objectives are to generate high-quality plans with few, large and regular segments, and to make the planning process more intuitive. The proposed method combines segment generation with ...

An electron-bombardment ion source has a chamber into which an ionizable propellant is introduced. Electrons flowing from a cathode to an anode serve to ionize the propellant. The resulting ions are accelerated out of the chamber. To increase the efficiency of ionization of the propellant by the electrons, a magnetic field is established within the chamber. To that end, there ...

Short communication All joint moments significantly contribute to trunk angular acceleration: Accepted 19 April 2010 Keywords: Gait Trunk control Balance Angular acceleration Sensitivity a b s t r a c can produce linear and angular acceleration of all body segments (including those on which the moment

The accelerator mass spectrometry programme and the related developments based on the BARC-TIFR Pelletron accelerator is described. A segmented gas detector and beam chopper control electronics have been developed for conducting 36Cl measurements. Distinct energy loss characteristics of the gas detector and beam chopper performance are ...

Few studies have investigated the factors related to the disability and physical function in degenerative lumbar spondylolisthesis using axially loaded magnetic resonance imaging (MRI). Therefore, we aimed to investigate the effect of axial loading on the morphology of the spine and the spinal canal in patients with degenerative spondylolisthesis of L4�5 and to correlate morphologic changes to ...

Few studies have investigated the factors related to the disability and physical function in degenerative lumbar spondylolisthesis using axially loaded magnetic resonance imaging (MRI). Therefore, we aimed to investigate the effect of axial loading on the morphology of the spine and the spinal canal in patients with degenerative spondylolisthesis of L4-5 and to correlate morphologic changes to ...

The most harmful resonances of vertical oscillations in the segment cyclotron can be eliminated if the relation omega /sub z// omega < 1/2 takes place at the beginning of acceleration where omega /sub z/, is the frequency of vertical oscillations and omega is the frequency of ion revolutions. In some cases, when the prescribed course of ...

Segmented electrodes with a low secondary electron emission are shown to alter significantly plasma flow in the ceramic channel of the Hall thruster. The location of the axial acceleration region relative to the magnetic field can be moved. The radial potential distribution can also be altered near the channel walls. A hydrodynamic model shows that these ...

Variable plasma jet velocity with low beam divergence over a range of mass flow rates can be achieved through segmented electrode operation of Hall plasma accelerator. With the use of just a cathode side electrode at the cathode potential, the beam divergence can be decreased substantially, at some cost in efficiency. However, the additional use of an ...

A muscle produces moments at the joints it crosses, but these moments can also cause accelerations at joints not crossed by the muscle. This phenomenon, the acceleration of a joint caused by a muscle not crossing the joint, is referred to as induced acceleration. For a system of rigid bodies this study examines how system ...

A novel method for measuring human gait posture using wearable sensor units is proposed. The sensor units consist of a tri-axial acceleration sensor and three gyro sensors aligned on three axes. The acceleration and angular velocity during walking were measured with seven sensor units worn on the abdomen and the lower limb segments ...

The purpose of this study was to determine whether the introduction of larger and heavier beds which were lower to the floor increased the physical stress on employees responsible for room cleaning and bedmaking in the hospitality industry. More specifically, this study assessed the effect of bed size (single, double and king) and bed height (460 and 560 mm) on dynamic and static estimates of ...

We present a case that had two separate facet joints on the same side causing an intervertebral instability. The embryological pathogenesis of the congenital existence of two separate facet joints on the same side of the vertebra is not conclusively known. A 68-year-old woman presented with lower back pain and severe left leg pain. Neuroradiological evaluation including dynamic plain radiography, ...

Synovial cysts of the facet joints are uncommon lesions which may be asymptomatic or present as low back pain, with or without radicular symptoms. They are considered to be secondary to trauma or degenerative joint disease, and they occur more frequently in patients with spondylolisthesis. Diagnosis is normally achieved with computed tomography or magnetic resonance, which show a cystic lesion ...

Previous reports of posterolateral fusion for treatment of adolescent spondylolisthesis at L5-S1 suggest that persistent slippage is a significant problem in the postoperative period. Of 40 adolescent patients who underwent posterolateral fusion for L5-S1 spondylolisthesis, 23 demonstrated Grade 3 slip or worse. Two patients had progression of the slip postoperatively with subsequent spontaneous ...

Prospective study. To study the validity of Hybrid construction (Anterior Lumbar Interbody Fusion) ALIF at one level and total disc arthroplasty (TDA) at adjacent, for two levels disc disease in lumbar spine as surgical strategy. With growing evidence that fusion constructs in the treatment of degenerative disc disease (DDD) may alter sagittal balance and contribute to undesirable complications in ...

Prospective study. To study the validity of Hybrid construction (Anterior Lumbar Interbody Fusion) ALIF at one level and total disc arthroplasty (TDA) at adjacent, for two levels disc disease in lumbar spine as surgical strategy. With growing evidence that fusion constructs in the treatment of degenerative disc disease (DDD) may alter sagittal balance and contribute to undesirable complications in ...

The attempt to preserve motion below a long fusion is certainly praiseworthy even if it is clearly understood with the patient that the result might be only temporary, buying some good years in the most active part of life. The analysis of the case presented here suggests that such an approach could be recommended in the right patient, with the right team. More experience and reports are necessary ...

Accelerator injector designs have been evaluated using two computer codes. The first code self consistently follows relativistic particles in two dimensions. Fields are obtained in the Darwin model which includes inductive effects. This code is used to study cathode emission and acceleration to full injector voltage. The second code transports a fixed ...

Accelerator injector designs have been evaluated using two computer codes. The first code self consistently follows relativistic particles in two dimensions. Fields are obtained in the Darwin model which includes inductive effects. This code is used to study cathode emission and acceleration to full injector voltage. The second code transports a fixed ...

Impact forces and shock deceleration during jumping and running have been associated with various knee injury etiologies. This study investigates the influence of jump height and knee contact angle on peak ground reaction force and segment axial accelerations. Ground reaction force, segment axial acceleration, and ...

The use of intensity modulation with multiple static fields has been suggested by many authors as a way to achieve highly conformal fields in radiotherapy. However, quality assurance of linear accelerators is generally done only for beam segments of 100 MU or higher, and by measuring beam profiles once the beam has stabilized. We propose a set of ...

An approximate method is presented for determinng the response of an accelerometer to a polygonal acceleration pulse or to a curvilinear pulse which has been approximated by a series of straight line segments. The accelerometer is completely characterized by its natural frequencys the damping is not considered a variable. The treatment assumes ...

We have directly measured the damping of wake-field deflection modes in a slow-wave accelerating structure consisting of a dielectric-lined waveguide with segmented conducting boundaries wrapped with rf absorbing material. Such damping of deflection modes is desired to prevent beam breakup instabilities. Attenuation {ital e}-folding times of 246 ps were ...

The paper reports on an experimental analysis of the quantitative differences in the motion of bodies explosively accelerated in plane symmetry (the acceleration of plates) and in cylindrical symmetry (the acceleration of cylindrical segments). Experiments used a main charge of homogeneous thermoplastic explosive ...

Synthetic bio-molecular spiders with �legs� made of single-stranded segments of DNA can move on a surface which is also covered by single-stranded segments of DNA complementary to the leg DNA. In experimental realizations, when a leg detaches from a segment of the surface for the first time it alters that ...

Abstract. Automatically segmenting subcortical structures in brain images has the potential to greatly accelerate drug trials and population studies of disease. Here we propose an automatic subcortical segmentation algorithm using the auto context model (ACM). Unlike many segmentation algorithms that separately ...

The size of volume data field which is constructed by large-scale war industry product ICT images is large, and empty voxels in the volume data field occupy little ratio. The effect of existing ray casting accelerated methods is not distinct. In 3D visualization fault diagnosis of large-scale war industry product, only some of the information in the volume data field can help ...

The Federal Power Commission staff recommended the consideration of accelerated construction of high capacity electric transmission circuits on the Gulf Coast segment of the Southern Company's system as one means of recurrence of the power disturbance whi...

In the past, laboratory simulators have, because of technical limitations, usually been restricted to reproduce isolated segments of the operational environment. The next generation of simulators will provide the ability to create the high-magnitude, comp...

This site provides a simulation of a ball rolling on a segmented ramp. First, the user sets the ball's initial position and speed and the geometry of the ramp. Then the applet calculates the position, velocity, and acceleration of the ball and displays these in real time. The site also provides drawing tools for users to draw graphs by hand.

A large-acceptance, highly segmented electromagnetic lead glass calorimeter for Experiment E781 (SELEX) at Fermi National Acceleration Laboratory was designed and built. This detector has been used to reconstruct photons and electrons with energies rangin...

The rail gun offers an attractive alternative to the traveling wave rifle for the magnetic acceleration of macroscopic (0.05 g) bullets for impact fusion. In this paper we review the basic rail gun equations and indicate how energy efficiency can be desig...

Estimates of area-averaged, tidal bottom stress are made for four channel segments of the Great Bay Estuary, New Hampshire. Sea level and current measurements are used to estimate pressure gradient and acceleration terms in the equation of motion, while t...

The coupled equations of motion for a circular ring or circular ring segment are developed for the case where the ring is rotating about an axis in its plane and subjected to an angular velocity as well as an angular acceleration. Coupling results from be...

Memphis and Shelby County are geographically close to the southern segment of the New Madrid seismic zone (NMSZ). The NMSZ is being regarded by seismologists and earthquake engineers as the most hazardous zone in the eastern United States. In the study, a...

This paper addresses the automatic image segmentation problem in a region merging style. With an initially over-segmented image, in which the many regions (or superpixels) with homogeneous color are detected, image segmentation is performed by iteratively merging the regions according to a statistical test. There are two essential ...

The novel design of a 1 MeV3He+ radiofrequency quadrupole (RFQ) accelerator is discussed. This RFQ is the first segment of an accelerator for the production of radioisotopes for positron emission tomography (PET) applications. This RFQ is unusual in that two specific innovations were incorporated into the design. The mechanical design ...

In this paper, we study the single bunch transverse beam dynamics in the presence of random displacements of resistive wall segments and focusing elements. Analytical formulas are obtained for long-range resistive wall wake, together with numerical results for short-range resistive wall wake. The results are applied to the LCLS project and some other proposed ...

In this paper, we study the single bunch transverse beam dynamics in the presence of random displacements of resistive wall segments and focusing elements. Analytical formulas are obtained for long-range resistive wall wake, together with numerical results for short-range resistive wall wake. The results are applied to the LCLS project and some other proposed ...

Method and apparatus for monitoring characteristics of a high energy neutral beam. A neutral beam is generated by passing accelerated ions through a walled cell containing a low energy neutral gas, such that charge exchange neutralizes the high energy ion beam. The neutral beam is monitored by detecting the current flowing through the cell wall produced by low energy ions ...

Enthusiasm for cervical disc arthroplasty is based on the premise that motion-preserving devices attenuate the progression of adjacent-segment disease (ASD) in the cervical spine. Arthrodesis, on the other hand, results in abnormal load transfer on adjacent segments, leading to the acceleration of ASD. It has taken several decades of ...

Since 2009 an Alignment Diagnostic System (ADS) has been operating at the undulator of the new Linac Coherent Light Source at SLAC National Accelerator Laboratory. The undulator spans a distance of 132 meters and is structured into 33 segments. Each segment is equipped with four hydrostatic leveling sensors and four wire position ...

An 8-m-long 4-vane radio frequency quadrupole (RFQ) has been proposed by LANL for use in high-current proton accelerators. This RFQ is made up of four 2-m-long coupled segments; the end regions and segment joints need full 3D modeling. In this paper, the strategies for piecewise treatment of the RFQ and results of the modeling are ...

BackgroundSnake venoms consist primarily of proteins and peptides showing a myriad of potent biological activities which have been shaped by both adaptive and neutral selective forces. Venom proteins are encoded by multigene families that have evolved through a process of gene duplication followed by accelerated evolution in the protein coding region.ResultsHere we report five ...

An automatic variational level set segmentation framework for Computer Aided Dental X-rays Analysis (CADXA) in clinical environments is proposed. Designed for clinical environments, the segmentation contains two stages: a training stage and a segmentation stage. During the training stage, first, manually chosen representative images ...

The + Gz acceleration of prolonged duration alters the sanguine outputs circulating in the various segments of the human body. The purpose of the study to evaluate the yield variations in the primary carotid artery under + Gz acceleration, which condition...

In 2004, the Support Wide Area Network (SWAN) system added significant capability to the way Marines communicate on the battlefield. Today, the SWAN system is still a critical segment in Marine communications and the TCP accelerator is being evaluated for...

A plasma device is proposed utilizing a magnetic bottle and a 3-phase oscillator at the cyclotron frequency. The oscillator generates a rotating segment of increased magnetic field which transfers energy to the ions. This raises their velocity without external acceleration and creates new ions in the region by collision, obviating the need for a ...

INTRODUCTION: The purpose of this study was to determine whether fusion causes adjacent segment degeneration or whether degeneration is due to disease progression. MATERIALS AND METHODS: Eighty-seven patients that had undergone single level anterior cervical decompression and fusions with at least 5�years of follow-up were enrolled in this retrospective study. ...

An original method called the three-cubic method is proposed to generate online robot joint trajectories interpolating given position points with associated velocities. The method is based on an acceleration profile composed of three cubic polynomial segments, which ensure a zero acceleration at each intermediate point. Velocity and ...

PURPOSE: Both the antero-posterior and anterior approaches have been used for treating L5-S1 vertebral tuberculosis. However, no studies have compared the efficacy of the two methods in treating the disease. METHODS: The antero-posterior (AP group, 14 cases) and anterior (A group, 13 cases) approaches were ...

An apparent goal of the human postural system is to maintain head stability during walking. Although much is known about sensory-motor stabilising mechanisms associated with the head and neck, less is known about how the postural system attenuates motion between the trunk and neck segments in order to regulate head motion. Therefore the purpose of this study was to determine ...

Muscles coordinate multijoint motion by generating forces that cause reaction forces throughout the body. Thus, a muscle can redistribute existing segmental energy by accelerating some segments and decelerating others. In the process, a muscle may also produce or absorb energy, in which case its summed energetic effect on the ...

One of the keystones of the canceled BTeV experiment (proposed at Fermilab's Tevatron) was its sophisticated three-level trigger. The trigger was designed to reject 99.9% of light-quark background events and retain a large number of B decays. The BTeV Pixel Detector provided a 3-dimensional, high resolution tracking system to detect B signatures. The Level 1 pixel detector trigger was ...

A Segmented Rail Surface (SRS) structure is described that eliminates restrike arcs by progressively disconnecting segments of the rail surface after the plasma armature has passed. This technique has been demonstrated using the Los Alamos MIDI-2 railgun. Restrike was eliminated in a plasma armature acceleration experiment using ...

Circuit means is described for effecting inward transla- ' tory motion of the intensified terminal reflector field regions of a magnetic mirror plasma containment field with a simultaneous intensification of the over-all field configuration. The circuit includes a segmented magnetic field generating solenoid and sequentially actuated switch means to ...

We present a modular microwave excited electron cyclotron resonance type linear ion source concept that allows the adaptation of the ion beam dimensions to the requirements of the particular application. The ion beam current density profile is controlled by dividing the middle grid of a triple-grid system into segments of 2 cm width. Each segment is ...

We present a modular microwave excited electron cyclotron resonance type linear ion source concept that allows the adaptation of the ion beam dimensions to the requirements of the particular application. The ion beam current density profile is controlled by dividing the middle grid of a triple-grid system into segments of 2 cm width. Each segment is ...

. The ability of ultrasound scanners to image anatomical structures in real time have led to their use in two important applications of medicine, (1) for monitoring the unborn baby (fetal ultrasound), and, (2) coronary treatment of blockages in blood vessels (intravascular ultrasound). The generated images (in the form of a continuous video) are typically noisy and contain numerous artifacts, ...

We present the case of a patient with a spondylolisthesis of L5 on S1 due to spondylolysis at the level L5/S1. The vertebral slip was fixed and no anterior instability was found. Using functional magnetic resonance imaging (MRI) in an upright MRI scanner, posterior instability at the level of the spondylolytic ...

Background:Traumatic unilateral facet dislocation without fracture is an uncommon injury of the lumbosacral junction. We describe a case of a unilateral perched L5�S1 facet causing axial back pain and radiculopathy provoked by motion.Case Description:The patient underwent reduction with complete facetectomy ...

There is substantial controversy in literature about human dermatomes. We studied L4, L5, and S1 inferior limb dermatomes by comparing clinical signs and symptoms with conduction studies, electromyographical data, neurosurgical findings, and imaging data from computerized tomography (CT) or magnetic resonance imaging (MRI). After analyzing 60 patients, we concluded that L4 is probably located in ...

Field-Reversed Configurations (FRCs) can be used to fuel tokamaks by accelerating them to velocities high enough to penetrate the toroidal field, as demonstrated in the TRAP experiment at this laboratory1. In this thesis we examine in detail, using numerical and analytical models, the physics of the acceleration and compression phases of an FRC fueler. The ...

For the step-and-shoot intensity-modulated radiation therapy (IMRT) technique, the combination of high dose rate, multiple beam segments and low dose per segment can lead to significant differences between the planned dose and the dose delivered to the patient. In this technique, a dose delivery inaccuracy known as the 'overshoot' effect is caused by the ...

Investigation into the dynamic viscosity change on curing of seven segmented polyurethane polymers has shown that initial viscosities decrease with temperature while the rate of cure and change in viscosity depend directly on temperature. The polyurea hard segment (87 and 88) systems cured more rapidly than polyurethane hard segment ...

BackgroundSpinal manipulation has been found to create demonstrable segmental and intersegmental spinal motions thought to be biomechanically related to its mechanisms. In the case of impulsive-type instrument device comparisons, significant differences in the force-time characteristics and concomitant motion responses of spinal manipulative instruments have been reported, but ...

A new method using a double-sensor difference based algorithm for analyzing human segment rotational angles in two directions for segmental orientation analysis in the three-dimensional (3D) space was presented. A wearable sensor system based only on triaxial accelerometers was developed to obtain the pitch and yaw angles of thigh ...

Due to the mechanical coupling between the body segments, it is impossible to see with the naked eye the causes of body movements and understand the interaction between movements of different body parts. The goal of this paper is to investigate the use of induced acceleration analysis to reveal the causes of body movements. We derive the analytical ...

The purpose of this study is to clarify effects of three-dimensional phenomena on performance of the Magnetohydrodynamic (MHD) accelerator for the MAPX project at NASA Marshal Space Flight Center. Generally, in a Faraday type of MHD accelerator with segmented electrode, high flow velocity augmentation can be achieved. However, many ...

Linear accelerations measurements are needed in many applications, as industry, military, aircrafts, space navigation, robotics and others. Actually, the most usual solutions to measure linear accelerations are three piezoelectric sensors used in orthogonal mounting, or MEM's sensors chips. Angular accelerations also are interesting to ...