Transverse Arm Research Articles

Potential problem and solution of lateral plate postposition for the posterolateral tibial plateau fracture

BackgroundThere has been controversial for the treatment of the posterolateral tibial plateau fractures (PTPF). This study aimed to evaluate clinic outcomes of the lateral locking compression plate (LCP) postposition, analyze the feasibility of LCP postposition through anatomical measurement, and address the potential problems of LCP postposition through the biomechanical assessment.Methods39 patients with PTPF undergoing LCP fixation between June 2019 and June 2022 were retrospectively evaluated. All cases were divided into two group: Group A (15 cases) employed plate transverse arm postpositioning with posterolateral (PL) fracture fixation using two raft screws, while Group B (24 cases) utilized non-postpositioning with fixation by a single raft screw. Surgical duration, intraoperative blood loss, the change of lateral tibial plateau angle (LTPA), lateral tibial plateau posterior slope angle (LPSA) and fracture collapse between immediate postoperative and last follow up, range of motion (ROM), HSS knee score, and Lysholm knee score were recorded. CT measurements of the fibular head superior space and LCP transverse arm were taken in 50 healthy adult knees to assess postposition feasibility. Finally, three fracture models were established using finite element analysis: Model A with plate postposition and PL split fracture fixed by two raft screws of transverse arm, Model B with plate non-postposition and PL split fracture fixed by one raft screw, and Model C with plate non-postposition and PL split fracture fixed by one raft screw and anterior–posterior tension screws. Loadings of 250N, 500N, and 750N were applied for the analysis of the displacement degree, von Mises stress distribution.ResultsResults indicate comparable operative duration and intraoperative hemorrhage between groups. Complications were minimal in both groups. Group A demonstrated superior outcomes in terms of radiographic parameters, functional scores, and fracture collapse prevention. CT measurements revealed compatibility in 72% of healthy knees with the postpositioning technique. Finite element analysis indicated favorable biomechanical stability.ConclusionNot all patients with PTPF were applicable to the management of the plate postposition and two raft screws fixation, even though this technique exerted good biomechanical stability and achieved satisfactory clinic outcomes. When the PL fracture was fixed by only raft screw through LCP owing to various reasons, two anterior–posterior tension screws might be necessitated to maintain the fracture stability.

Aerodynamic Performance Analysis of VTOL Arm Configurations of a VTOL Plane UAV Using a Computational Fluid Dynamics Simulation

A vertical take-off and landing plane (VTOL plane) is a fixed-wing unmanned aerial vehicle (FWUAV) configuration with the ability to take off and land vertically. It combines the benefits of fixed-wing and multirotor configurations, which gives it a high cruising range and independence from a runway. This configuration requires arms as mountings for the VTOL’s motors. This study discusses the design of a VTOL Plane with various VTOL arm configurations, and a computational fluid dynamics (CFD) simulation was conducted to find out which configuration performs the best aerodynamically. The VTOL arm configurations analyzed were a quad-plane, a twin-tail boom, a tandem wing, and a transverse arm. The interpreted performances were the lift and drag performances, stall conditions, flight efficiency, stability, and maneuverability. The relative wind directions toward the longitudinal axis of the UAV, which are the sideslip angle and the angle of attack, were varied to simulate various flying conditions. The results showed that the twin tail-boom is the most advantageous based on the interpreted performances.

Analysis of aerodynamic and aeroacoustics of full scale landing gear

The aerodynamic noise of a landing gear is an important source of airframe noise. The analysis of its noise characteristics plays an important role in the design of a low-noise landing gear. Based on the FL-52 acoustic wind tunnel test technology, the coupled scale adaptive model and the acoustic disturbance equation, the results on aerodynamic noise of a full-scale landing gear model are analyzed. The high-fidelity model includes transverse strut, torsion arm, piston rod, wheel and other parts. The characteristics of static pressure distribution, power spectrum density of pulsating pressure, aerodynamic noise source distribution and directivity of overall sound pressure level are analyzed. The noise characteristics of the far-field microphone are compared with the local microphone installed in the wheel cavity. In this way, we characterize the directivity of pure tone in the wheel cavity and understand its contribution to the far-field noise. The results show that the aerodynamic noise of the landing gear can be quantified accurately by the hybrid numerical method. The pure tone has two frequencies inside and outside the wheel of the landing gear: 560 Hz and 960 Hz. The peak of the loudest sound pressure level reaches 136 dB, and the pure tone radiates to the surface of the non-separation area of the wheel of the landing gear. However, the wall pressure spectrum of the points located in the turbulence region shows a wide-frequency characteristic, and there is no obvious pure tone. From the point of view of the far-field noise directivity, the forward noise of the landing gear is larger than the rear noise, and there is a small overall sound pressure level area at the points of 65 and 110 degrees respectively. When the monitoring points are far away, the far-field noise of the landing gear shows the characteristics of wide frequency, and no obvious pure tone appears. The method can provide the technical support for predicting the aeroacoustics of a landing gear and designing a low-noise land gear.

How octopus arm muscle contractile properties and anatomical organization contribute to arm functional specialization.

Octopus arms are highly flexible structures capable of complex motions and are used in a wide repertoire of behaviors. Movements are generated by the coordinated summation of innervation signals to packed arrays of muscles oriented in different directions and moving based on their anatomical relationships. In this study, we investigated the interplay between muscle biomechanics and anatomical organization in the Octopus vulgaris arm to elucidate their role in different arm movements. We performed isometric and isotonic force measurements on isolated longitudinal and transverse arm muscles and showed that longitudinal muscles have a higher rate of activation and relaxation, lower twitch-to-tetanus ratio and lower passive tension than transverse muscles, thus prompting their use as faster and slower muscles, respectively. This points to the use of longitudinal muscles in more graded responses, such as those involved in precise actions, and transverse muscles in intense and sustained actions, such as motion stabilization and posture maintenance. Once activated, the arm muscles exert forces that cause deformations of the entire arm, which are determined by the amount, location, properties and orientation of their fibers. Here, we show that, although continuous, the arm manifests a certain degree of morphological specialization, where the arm muscles have a different aspect ratio along the arm. This possibly supports the functional specialization of arm portions observed in various motions, such as fetching and crawling. Hence, the octopus arm as a whole can be seen as a 'reservoir' of possibilities where different types of motion may emerge at the limb level through the co-option of the muscle contractile properties and structural arrangement.

A Novel Single-Feed Filtering Dielectric Resonator Antenna Using Slotline Stepped-Impedance Resonator

A novel single-feed filtering dielectric resonator antenna (FDRA) with quasi-elliptic bandpass response is proposed in this brief. The proposed FDRA consists of a shunted slotline stepped-impedance resonator (SSIR), a rectangular dielectric resonator antenna (DRA) and a microstrip feedline with a pair of transverse arms. The antenna is excited in the fundamental TE <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{11\delta }$ </tex-math></inline-formula> mode, the transverse arm mode and the two SSIR modes. Moreover, three radiation nulls are produced near the edges of the passband by the SSIR and the transverse arm of microstip feedline, respectively. A prototype FDRA is fabricated and measured, which offers a bandwidth ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$| S_{11} | &lt; -10$ </tex-math></inline-formula> dB) of 21.14% (3.13 - 3.87 GHz), and a peak realized gain of 5.3 dBi within passband. The realized gain shows a decline of 20 dB at passband-edge, which exhibits high selectivity.

How does external lateral stabilization constrain normal gait, apart from improving medio-lateral gait stability?

Background: The effect of external lateral stabilization on medio-lateral gait stability has been investigated previously. However, existing lateral stabilization devices not only constrain lateral motions but also transverse and frontal pelvis rotations. This study aimed to investigate the effect of external lateral stabilization with and without constrained transverse pelvis rotation on mechanical and metabolic gait features. Methods: We undertook two experiments with 11 and 10 young adult subjects, respectively. Kinematic, kinetic and breath-by-breath oxygen consumption data were recorded during three walking conditions (normal walking (Normal), lateral stabilization with (Free) and without transverse pelvis rotation (Restricted)) and at three speeds (0.83, 1.25 and 1.66 m s−1) for each condition. In the second experiment, we reduced the weight of the frame, and allowed for longer habituation time to the stabilized conditions. Results: External lateral stabilization significantly reduced the amplitudes of the transverse and frontal pelvis rotations, in addition to medio-lateral, anterior–posterior, and vertical pelvis displacements, transverse thorax rotation, arm swing, step length and step width. The amplitudes of free vertical moment, anterior–posterior drift over a trial, and energy cost were not significantly influenced by external lateral stabilization. The removal of pelvic rotation restrictions by our experimental set-ups resulted in normal frontal pelvis rotation in Experiment 1 and significantly higher transverse pelvis rotation in Experiment 2, although transverse pelvis rotation still remained significantly less than in the Normal condition. Step length increased with the increased transverse pelvis rotation. Conclusion: Existing lateral stabilization set-ups not only constrain medio-lateral motions (i.e. medio-lateral pelvis displacement) but also constrain other movements such as transverse and frontal pelvis rotations, which leads to several other gait changes such as reduced transverse thorax rotation, and arm swing. Our new set-ups allowed for normal frontal pelvis rotation and more transverse pelvis rotation (yet less than normal). However, this did not result in more normal thorax rotation and arm swing. Hence, to provide medio-lateral support without constraining other gait variables, more elaborate set-ups are needed.

Force and strength analysis of FSAE racing suspension based on spatial analytic geometry

Based on spatial analytic geometry, the paper established a mechanical of suspension system, which is aimed at the structure of double transverse arm suspension of FSAE racing car. Combined with the typical driving conditions of the car, we have worked it out with the MATLAB. Based on that, we have made the finite element static checking analysis with ANSYS, which is aimed at providing effective basis for the design and optimization of racing car.

Femilis(®) 60 Levonorgestrel-Releasing Intrauterine System-A Review of 10 Years of Clinical Experience.

OBJECTIVEThe aim of this study was to update the clinical experience with the Femilis® 60 levonorgestrel-releasing intrauterine system (LNG-IUS), now up to 10 years in parous and nulliparous women, particularly with regard to ease and safety of insertion, contraceptive performance, retention, acceptability, continuation of use, impact on menstrual blood loss (MBL), and duration of action.STUDY DESIGNUsing the Femilis® 60 LNG-IUS releasing 20 µg of levonorgestrel/day, the following studies were conducted: an open, prospective noncomparative contraceptive study, an MBL study, a perimenopausal study, a study for the treatment of endometrial hyperplasia, and early cancer of the uterus, a residue study.RESULTSA total of 599 Femilis LNG-IUS were inserted in various clinical trials, the majority for contraceptive purposes. The total exposure in the first and second contraceptive studies, covering 558 parous and nulliparous women, was 32,717 woman-months. Femilis has high contraceptive effectiveness as only one pregnancy occurred. Expulsion of the LNG-IUS was rare with only two total and no partial expulsions (stem protruding through the cervical canal) occurred. Femilis was well tolerated, with continuation rates remaining high. Several MBL studies were conducted, totaling 80 heavy and normal menstrual bleeders, using the pictorial bleeding assessment chart method or the quantitative alkaline hematin technique. Virtually all women responded well with strongly reduced menstrual bleeding. Amenorrhea rates were high, up to 80% after three months, and ferritin levels simultaneously increased significantly. The Femilis LNG-IUS was tested in 104 symptomatic perimenopausal women for seamless transition to and through menopause, adding estrogen therapy when required. Patient tolerability appeared high as >80% requested a second and a third LNG-IUS. Twenty women presenting with nonatypical and atypical hyperplasia and one woman presenting with early endometrial carcinoma were treated with Femilis LNG-IUS. All histology specimens showed full regression, and patients remained in remission without signs of hyperplasia or cancer at yearly and ongoing follow-up examinations up to 10 years. Residual content of LNG was measured in 37 women having the Femilis LNG-IUS for up to 10 years. In 10 of the 102 women who had the Femilis 60 in situ for 10 years between 20% and 30% of the original 60 mg was recovered confirming the long duration of action of the Femilis 60 LNG-IUS.CONCLUSIONThese studies suggest that the Femilis 60 LNG-IUS releasing 20 µg of LNG/day is an effective, well-tolerated, and well-retained contraceptive both in parous and in nulliparous women. The design of the LNG-IUS, with flexible transverse arm(s) length of 28 mm, allows for a simplification of the insertion technique and training requirements facilitating the use by nonspecialist providers in either developed or developing countries. For nulliparous women, additional evaluation of devices with a 24 mm transverse arm(s), as it relates to tolerability, retention, and continuation of use, still needs to be undertaken.

Practical Advice for Emergency IUD Contraception in Young Women.

Too few women are aware of the very high efficacy of intrauterine copper devices (IUDs) to prevent pregnancy after unprotected intercourse. Women who frequently engage in unprotected intercourse or seek emergency contraception (EC) are at high risk of unplanned pregnancy and possible abortion. It is therefore important that these women receive precise and accurate information about intrauterine devices as they may benefit from using an IUD for EC as continuing contraception. Copper IUDs should be used as first choice options given their rapid onset of action and their long-term contraceptive action which require minimal thought or intervention on the part of the user. In the United States, there is only one copper IUD presently available which limits treatment options. There are numerous copper IUDs available for use in EC, however, their designs and size are not always optimal for use in nulliparous women or women with smaller or narrower uteruses. Utilization of frameless IUDs which do not require a larger transverse arm for uterine retention may have distinct advantages, particularly in young women, as they will be suitable for use in all women irrespective of uterine size. This paper provides practical information on EC use with emphasis on the use of the frameless IUD.

Precision intrauterine contraception may significantly increase continuation of use: a review of long-term clinical experience with frameless copper-releasing intrauterine contraception devices

ObjectiveThe purpose of this paper is to review the experience with the frameless, anchored, GyneFix copper-releasing intrauterine contraceptive devices (IUCDs/IUDs) (Contrel Europe, Belgium), and to demonstrate their high acceptability and low rate of discontinuation of use, which could contribute to current efforts that aim to reduce radically the high number of unintended pregnancies and induced abortions, particularly in young women.Materials and methodsThis paper is based on studies that examined the differences in uterine volume and cavity size, related to age and parity, and on original clinical research data and practical experience with frameless copper IUDs, as well as on literature data on the IUD–endometrial cavity relationship of conventional IUDs, with special reference to side effects and user discontinuation.ResultsThe mean transverse diameter in nulliparous and parous women is significantly less than the length of the transverse arm of the TCu380A IUD (ParaGard, Duramed, NY, USA) or the levonorgestrel intrauterine system (Mirena, Bayer, Germany). Small, frameless, flexible, and unidimensional copper IUDs appear to be well tolerated, with less impact on menstrual bleeding, resulting in low discontinuation rates when compared with standard-size conventional IUDs, which often result in increased expulsion rates, complaints of pain and erratic or increased menstrual bleeding, and subsequent high rates of discontinuation, particularly in young women.ConclusionThe unidimensional GyneFix IUDs fit the majority of uterine cavities. An IUD that fits is likely to result in increased tolerance and continued use of the method. As this would appeal to women, the logical result should be greater use of the method and fewer unintended pregnancies and induced abortions. Recommending the standard TCu380A (ParaGard) IUD or the Mirena levonorgestrel intrauterine system, primarily developed for use in parous women, for general use in nulliparous and adolescent women should be done with caution in the light of current scientific evidence, except if 3-D sonography indicates that the uterine cavity is sufficiently large.

Mixed-mode crack initiation at the edge of Cu/Si interface due to nanoscale stress concentration

To investigate the crack initiation behavior under the mixed-mode at the edge of a Cu/Si interface in nanoscale components, fracture experiments are conducted by a novel torsion method using a double nano-cantilever specimen consisting of a 20-nm-thick Cu layer and a Si substrate. This nano-cantilever torsion method can apply the shear stress to the Cu/Si interface with the nanoscale stress concentration through the transverse arm. The mode mixity, which is the ratio of the shear stress to the normal stress, can be precisely controlled by varying the loading position. The interface crack is successfully initiated at the Cu/Si edge for various mode mixities by the developed method. The detailed stress fields along the Cu/Si interface at the critical loads for crack initiation are analyzed by the finite element method, and the stress concentration region near the interface edge in all specimens is within the scale of 100nm. The critical normal stress and maximum shear stress at crack initiation have a circular relation.

SU‐E‐I‐95: Using Angular Magnitude Evaluate the Spatial Orienations in Computed‐Tomography Simulation System

Purpose: To quantify the spatial orientations of the tabletop and external patient positioning lasers with respect to the couch moving direction and imaging plane in a CT simulation system by indicating as angular deviation. Method and Materials:A home‐made cross‐jig is used in this study. The longitudinal arm of the jig is orthogonal with the transverse arm and some BB markers inlaid in the jig to indicate the arms on CT images. We found there are some relationships between the orientations of the jig arms which shown on the images and the orientations among the tabletop, external lasers, couch moving direction, and imaging plane. First, the orientations of CT simulation system had been carefully confirmed by using the approaches mentioned on TG 66. To simulate all possible deviating situations, we designed 8 orientation arrangements for the tabletop and external lasers, respectively, due to these two components cause different effects on CT images. When attaching the cross‐jig on tabletop we can check the orientations between the tabletop, couch moving direction, and imaging plane. While aligning the cross‐jig with the external lasers we will know the angular deviation between the external lasers, couch moving direction, and imaging plane. Results: Based on the preliminary analysis, the maximum error is 0.12 degree. After considering the inherent angular deviations in our CT simulator, image analysis errors due to the size of BB and image spatial resolution, and the jig setup errors we can say all of the results conformed to our expectation. Conclusions: Only two scans, then we will know the spatial orientations in CT simulation. By means of accurately quantifying the deviations we can easily correct the error if it has to be. The method proposed in this study could also be used for detecting an angular deviation in any other orthogonal imaging system.

Fatigue assessment of arc welded automotive components using local stress approaches: Application to a track control arm

The applicability of the structural and notch stress approach is examined on the basis of arc welded and dynamically loaded steel structures, taken from the automotive sector. In detail, this is a transverse control arm. Components and specimens with critical regions of failure are tested under cyclic loading with constant and variable amplitudes. With the help of strain gauges, the crack initiation is determined. The specimens are the basis for the application and evaluation of the different approaches for the assessment of fatigue life. The numerical determination of the nominal, structural and notch stresses is performed with finite-element models. Finally the experimental and computational results allow the derivation of structural and notch Woehler S–N curves.

Mechanism for domain wall pinning and potential landscape modification by artificially patterned traps in ferromagnetic nanowires

The interaction mechanism between transverse domain walls (TDWs) in Permalloy nanowires and artificially patterned traps is studied using high-sensitivity spatially resolved magneto-optical Kerr effect measurements and numerical simulations. T-shaped trap geometries are considered, where a DW traveling in the horizontal arm is pinned by the vertical arm. Pinning strengths as well as potential energy modifications created by the traps are measured, and the roles of the different DW characteristic parameters, such as the DW core orientation and the magnetic charge distribution within the DW, are presented. It is found that whether or not the core of the DW is aligned with the transverse arm of the T structure affects the shape of the main potential experienced by the DW, whereas the pinning strength strongly depends on which side of the V-shaped TDW interacts with the trap. The role of the magnetostatic interaction between the charge of the DW and the charge present at the junction is discussed.

Unilateral Transverse Arm Defect with Subterminal Digital Nubbins

We present a case of unilateral terminal transverse forearm deficiency with subterminal digit-like nubbins, identified in a fetus from a pregnancy terminated electively in the second trimester because the distal right arm and hand could not be seen by ultrasound and were presumed to be absent. Pathologic evaluation showed distal transverse shortening, tapering to a point in the mid-forearm. Five primitive digital nubbins were present, located just proximal to the tapered point. The arm vessels appeared normal histologically, and the amnion showed no evidence of intrauterine disruption. Histologic examination of the nubbins revealed osteocartilaginous tissue, never described previously within digital nubbins. This fetus has the rare phenotype of terminal transverse limb defects with residual nubbins, but differs in that the nubbins are not at the tip of the terminal transverse limb defect.

Prospective study on fetal weight estimation using limb circumferences obtained by three‐dimensional ultrasound

The aim of this prospective study was to evaluate the usefulness of fetal weight estimation in a prospective study, based on formulae derived from a previous retrospective study, using forward stepwise multiple regression analysis. Three-dimensional ultrasound was used to make reproducible measurement of limb circumferences, which formed the basis of our models. A total of 213 women with singleton pregnancies were scanned in the week prior to delivery and the following variables were measured: biparietal diameter, head circumference, transverse abdominal diameter, abdominal circumference, femur length, thigh circumference and arm circumference. The whole population was divided into three subgroups according to the abdominal circumference (< 10th centile, 10-90th centile, and > 90th centile). We demonstrated the need for only two models for accurate fetal weight estimation, one for the small-for-dates fetuses and a second for the others. The most accurate results were obtained for the macrosomic fetuses with a standard deviation of 8.8%. Our data confirm the usefulness of measurement of fetal thigh circumference for the the small-for-dates-fetuses and arm circumference for the other groups. We concluded that the use of three-dimensional ultrasound could facilitate the accurate prediction of fetal weight.

Perceptual distortion contributes to the curvature of human reaching movements.

Unconstrained point-to-point human arm movements are generally gently curved, a fact which has been used to assess the validity of models of trajectory formation. In this study we examined the relationship between curvature perception and movement curvature for planar sagittal and transverse arm movements. We found a significant correlation (P < 0.0001, n = 16) between the curvature perceived as straight and the curvature of actual arm movements. We suggest that subjects try to make straight-line movements, but that actual movements are curved because visual perceptual distortion makes the movements appear to be straighter than they really are. We conclude that perceptual distortion of curvature contributes to the curvature seen in human point-to-point arm movements and that this must be taken into account in the assessment of models of trajectory formation.

Measurement of limb circumferences with three-dimensional ultrasound for fetal weight estimation.

A large number of formulae have been published for fetal weight estimation. This study examines the possibility of using three-dimensional ultrasound to measure the limb circumference. This technology provides us with the opportunity to visualize two simultaneous, orthogonal planes, allowing the exact determination of the transverse plane at the mid-point of the limb. A total of 157 patients were scanned in the week prior to delivery. The following variables were measured in 154 fetuses: biparietal diameter, head circumference, transverse abdominal diameter, abdominal circumference, femur length, thigh circumference and arm circumference. The whole population was split into three subgroups according to the abdominal circumference centile (< 10th centile, 10-90th centile, and > 90th centile), because this single variable has the strongest correlation with neonatal weight (R = 0.901). With forward stepwise multiple regression analysis, four models were elaborated, one for the whole population and one for each subgroup. The small-for-dates fetuses need a targeted formula including only two variables, thigh circumference and femur length. Our data suggest that the thigh circumference measurement improves the estimation for growth-retarded fetuses and that the arm circumference improves the weight prediction for the others. The measurement of the two variables, made possible with three-dimensional ultrasound, has improved our results in fetal weight estimation.

Fetal limb volume: a new parameter to assess fetal growth and nutrition.

Fetal growth and nutrition were evaluated using measurements of the subcutaneous tissues of the arm and leg to calculate limb volume. Arm measurements included transverse and anteroposterior arm thicknesses and subcutaneous tissue thickness; leg measurements included lengths and thicknesses of the humerus and femur, transverse and anteroposterior thigh thickness, and thigh subcutaneous tissue thickness. Volumes were calculated using equations with both circular and elliptical perimeters. Limb volume was found to be strongly correlated with gestational age, and may be a possible predictive factor of intrauterine growth retardation.

EFFECTS ON HAND-EYE COORDINATION OF TWO DIFFERENT ARM MOTIONS DURING COMPENSATION FOR DISPLACED VISION.

Comparisons were made between the compensations produced by sagittal and by transverse arm motions under equivalent conditions of exposure and test. Effects of exposure with sagittal motion generalize more to transverse than vice versa. The differences may be related to the greater precision of body midline judgments with saggital motion.