True Rotation Research Articles

Treatment changes of hypo- and hyperdivergent Class II Herbst patients.

To determine the relative effects of Herbst appliance therapy in hypo- and hyperdivergent patients. The treated group included 45 growing Class II, division 1, patients treated with stainless steel crown Herbst appliances, followed by fixed edgewise appliances. The untreated control group consisted of 45 Class II, division 1, subjects, matched to the treated sample based on Angle classification, age, sex, and pretreatment mandibular plane angle (MPA). Subjects were categorized as hypo- or hyperdivergent based on their MPAs. Pre- and posttreatment cephalograms were traced and superimposed on cranial base and mandibular structures. The primary effect of the Herbst in terms of maxillomandibular correction was in the maxilla. It significantly restricted maxillary growth, producing a "headgear effect." Mandibular treatment changes depended on divergence. Hyperdivergent patients experienced a deleterious backward true mandibular rotation with Herbst treatment. Hypodivergent patients, as well as untreated hypo- and hyperdivergent controls, underwent forward true mandibular rotation. However, hypodivergent chins did not advance any more than expected for untreated hypodivergent Class II patients. Hypo- and hyperdivergent patients benefit from the Herbst's headgear effect. While the mandibular growth of hypodivergent patients overcomes the negative rotational effects, hyperdivergent patients undergo a deleterious backward mandibular rotation and increases in facial height.

Mathematical modeling for explanation and prediction of treatment outcome in growing patients with anterior open bite malocclusion treated with rapid molar intruder and posterior bite blocks

PurposeRapid molar intruder (RMI) is a non-compliant treatment modality for correction of anterior open bite (AOB) in growing patients. The aim of this study is to explain the main treatment outcome (increase in overbite) by the other morphological changes after treatment with RMI and posterior bite blocks (PBBs). We also investigated the baseline characteristics that may help predict the treatment outcome. Subjects and methodsFourteen patients (mean age±SD=10.7±1.7year) with AOB malocclusion were treated with RMI springs and PBBs fixed on posterior teeth for 4 months. Patients were assessed before and after treatment using cephalometric radiographs. Multivariable regression model was developed to explain overbite change by the other morphological components. Single regressions of overbite change on baseline variables were conducted to determine best predictor of treatment outcome. ResultsTreatment produced significant increase in overbite. The change in overbite was best explained by the changes in facial axis angle, upper anterior dental heights and upper posterior dental heights. The best predictor for treatment outcome was the facial axis angle before treatment. ConclusionThe correction of AOB by the RMI may be explained by orthopedic and dental changes resulting from growth and treatment. The orthopedic changes consisting of counterclockwise mandibular true rotation is the strongest contributor to overbite increase. Patients with severe vertical growth pattern tend to have greater closure rate of open bite.

A thin flat shell finite element based on the strain approach with a true rotation

Dans le present article, nous proposons un nouvel element fini de coque a facette plane. C'est le resultat de la combinaison d'un element de membrane et d'un element de flexion, tous deux bases sur la formulation a base de deformation. Il est connu que les elements membranaires bidimensionnels de classe C° donnent une deflexion et des contraintes faibles pour les problemes a flexion dominante. En outre, ils rencontrent des problemes de continuite et de conformite lorsqu'ils sont connectes a des elements de plaque de classe C1. Le but du present travail est de surmonter ces problemes lorsqu'un element de membrane est couple a un element de plaque mince afin de construire un element de tcoque. L'element membranaire utilise est le T43_Eq developpe par Himeur et Col.. C'est un element triangulaire ayant quatre noeuds, trois noeuds aux sommets du triangle et le quatrieme a son barycentre. Chaque noeud possede trois degres de liberte, deux translations et une rotation autour de la normale. Les coefficients relatifs aux degres de liberte du noeud interne sont ensuite elimines de la matrice de rigidite elementaire en utilisant la technique de condensation statique. Les fonctions d'interpolation des champs de deformations, de deplacements et de contraintes sont developpees a partir des conditions d'equilibre. L'element de plaque utilise pour la construction du present element de coque est un element de plaque mince triangulaire a quatre noeuds developpe par Himeur et base sur : l'approche en deformation, le noeud fictif, la condensation statique et l'integration analytique. Le resultat de cette combinaison est robuste, competitif et efficace.

Neck Pain and Proprioception Revisited Using the Proprioception Incongruence Detection Test.

Proprioceptive imprecision is believed to contribute to persistent pain. Detecting imprecision in order to study or treat it remains challenging given the limitations of current tests. The aim of this study was to determine whether proprioceptive imprecision could be detected in people with neck pain by testing their ability to identify incongruence between true head motion and a false visual reference using the Proprioception Incongruence Detection (PID) Test. A cross-sectional study was conducted. Twenty-four people with neck pain and 24 matched controls repeatedly rotated to specific markers within a virtual world and indicated if their true head rotation was more or less than the rotation suggested by the visual feedback. Visual feedback was manipulated at 6 corrections, ranging from 60% of true movement to 140% of true movement. A standard repositioning error (RPE) test as undertaken for comparison. Healthy controls were better able to detect incongruence between vision and true head rotation (X̅=75.6%, SD=8.5%) than people with neck pain were (X̅=69.6%, SD=12.7%). The RPE test scores were not different between groups. The PID Test score related to self-reported pain intensity but did not relate to RPE test score. Causality cannot be established from this cross-sectional study, and further work refining the PID Test is needed for it to offer clinical utility. Proprioceptive precision for neck movement appears worse in people with neck pain than in those without neck pain, and the extent of the deficit appears to be related to usual pain severity. The PID Test appears to be a more sensitive test than the RPE test and is likely to be useful for assessment of proprioceptive function in research and clinical settings.

Determination of dynamic rotation factor for DWTT specimens by strain analysis and hardness measurement

As to accurately ascertain the value of dynamic rotation factor r*, strain analysis-based measurement was performed on the bent low-blow specimens by means of two approaches. (i) Surface strain analysis on the ligament indicates a critical transition zone from the necking to swelling, where the total strain reaches the minimum as undeformed material. (ii) Hardness measurement on the thickness-reduction specimen also reflects a typical V-shape distribution of interior plasticity along the ligament as observed from the surface, suggesting the location of true rotation centre relative to the neutral strain axis where the hardness is nearly invariable without any work hardening. As a result, the obtained value of r* maintains nearly 0.45 for (B × 4B) size drop-weight tear test-type specimens after their crack initiation and propagation, well consistent with the values calculated from the slip-line field theory.

M-Series with Adaptive Patterning for High-Yield Fan-Out SIP

Fan-Out Wafer Level Packaging (FOWLP) holds immediate promise for packaging semiconductor chips with higher interconnect density than the incumbent Wafer Level Chip Scale Packaging (WLCSP). FOWLP enables size and performance capabilities similar to WLCSP, while extending capabilities to include multi-device system-in-packages. FOWLP can support applications that integrate multiple heterogeneously processed die at lower cost than 2.5D silicon interposer technologies. Current industry challenges with die position yield after die placement and molding result in low-density design rules and the high-cost of accurate die placement. Efficiently handling die shift is essential for making FOWLP cost-competitive with other technologies such as FCCSP and QFN. This presentation will provide an overview of Adaptive Patterning, a new technology for overcoming variability of die positions after placement and molding. In this process, an optical scanner is used to measure the true XY position and rotation of each die after panelization. The die measurements are then fed into a proprietary software engine that generates a unique pattern for each package. The resulting patterns are dispatched to a lithography system, which dynamically implements the unique patterns for all packages within a panel. For system-in-packages, this process offers a unique advantage over a fixed pattern: each die shift can be handled independently. With a fixed pattern, the design tolerances need to be large enough for all die to shift in opposing directions, otherwise yield loss in incurred. With Adaptive Patterning, vias and RDL features remain at minimum size and are matched to the measured die shift. The die-to-die interconnects are dynamically generated and account for the unique position of each die. Thus, Adaptive Patterning retains the same high-density design rules regardless of how many die are in a package. Adaptive Patterning provides the capability to use high-throughput die placement to drive down cost, while enabling higher-density system-in-package interconnect. With this technology the industry can finally realize the cost, flexibility, and form factor benefits of FOWLP.

Is computed tomography an accurate and reliable method for measuring total knee arthroplasty component rotation?

Computed tomography (CT) is widely used to assess component rotation in patients with poor results after total knee arthroplasty (TKA). The purpose of this study was to simultaneously determine the accuracy and reliability of CT in measuring TKA component rotation. TKA components were implanted in dry-bone models and assigned to two groups. The first group (n = 7) had variable femoral component rotations, and the second group (n = 6) had variable tibial tray rotations. CT images were then used to assess component rotation. Accuracy of CT rotational assessment was determined by mean difference, in degrees, between implanted component rotation and CT-measured rotation. Intraclass correlation coefficient (ICC) was applied to determine intra-observer and inter-observer reliability. Femoral component accuracy showed a mean difference of 2.5° and the tibial tray a mean difference of 3.2°. There was good intra- and inter-observer reliability for both components, with a femoral ICC of 0.8 and 0.76, and tibial ICC of 0.68 and 0.65, respectively. CT rotational assessment accuracy can differ from true component rotation by approximately 3° for each component. It does, however, have good inter- and intra-observer reliability.

Long-term outcome of accessory nerve to suprascapular nerve transfer in obstetric brachial plexus lesion: functional, morphological, and electrophysiological results.

An accessory to suprascapular nerve (XIN-SSN) transfer is considered in patients with obstetric brachial plexus lesion who fail to recover active shoulder external rotation. The aim of this study was to evaluate the quality of extraplexal suprascapular nerve neurotization and to perform a detailed analysis of the infraspinatus muscle (IM) and shoulder external rotation. A XIN-SSN transfer was performed in 14 patients between 2000 and 2007. Patients had been operated at the age of 3.7 ± 2.8 years. Follow-up examinations were conducted up to 8.5 ± 2.5 years. Magnetic resonance imaging was performed to investigate muscle trophism. Fatty muscle degeneration of the IM was classified according to the Goutallier classification. We conducted nerve conduction velocity studies of the suprascapular nerve and needle electromyography of the IM to assess pathologic spontaneous activity and interference patterns. Active glenohumeral shoulder external rotation and global shoulder function were evaluated using the Mallet score. Postoperatively, growth of the IM increased equally on the affected and unaffected sides, although significant differences of muscle thickness persisted over time. There was only grade 1 or 2 fatty degeneration pre- and postoperatively. Electromyography of the IM revealed a full interference pattern in all except one patient, and there was no pathological spontaneous activity. Glenohumeral external rotation as well as global shoulder function increased significantly. Our results indicate that the anastomosis after XIN-SSN transfer is functional and that successful reinnervation of the infraspinatus muscle may enable true glenohumeral active external rotation.

3D barolo: a new 3D algorithm to derive rotation curves of galaxies

We present ^{3{D}}BAROLO,† a new code that derives rotation curves of galaxies from emission-line observations. This software fits 3D tilted-ring models to spectroscopic data cubes and can be used with a variety of observations: from H I and molecular lines to optical/IR recombination lines. We describe the structure of the main algorithm and show that it performs much better than the standard 2D approach on velocity fields. A number of successful applications, from high to very low spatial resolution data are presented and discussed. ^{3D}BAROLO can recover the true rotation curve and estimate the intrinsic velocity dispersion even in barely resolved galaxies (˜2 resolution elements) provided that the signal to noise of the data is larger than 2-3. It can also be run automatically thanks to its source-detection and first-estimate modules, which make it suitable for the analysis of large 3D data sets. These features make ^{3D}BAROLO a uniquely useful tool to derive reliable kinematics for both local and high-redshift galaxies from a variety of different instruments including the new generation Integral Field Units, ALMA and the SKA pathfinders.

Incorrect rotation curve of the Milky Way

In the fundamental quest of the rotation curve of the Milky Way, the tangent-point (TP) method has long been the simplest way to infer velocities for the inner, low latitude regions of the Galactic disk from observations of the gas component. We test the validity of the method on realistic gas distribution and kinematics of the Milky Way, using a numerical simulation of the Galaxy. We show that the resulting velocity profile strongly deviates from the true rotation curve of the simulation, as it overstimates it in the central regions, and underestimates it around the bar corotation. Also, its shape strongly depends on the orientation of the stellar bar. The discrepancies are caused by highly non-uniform azimuthal velocities, and the systematic selection by the TP method of high-velocity gas along the bar and spiral arms, or low-velocity gas in less dense regions. The velocity profile is in good agreement with the rotation curve only beyond corotation, far from massive asymmetric structures. Therefore the observed velocity profile of the Milky Way inferred by the TP method is expected to be very close to the true Galactic rotation curve for 4.5<R<8 kpc. Another consequence is that the Galactic velocity profile for R<4-4.5 kpc is very likely flawed by the non-uniform azimuthal velocities, and does not represent the true Galactic rotation curve, but instead local motions. The real shape of the innermost rotation curve is probably shallower than previously thought. Using a wrong rotation curve has a dramatic impact on the modelling of the mass distribution, in particular for the bulge component of which derived enclosed mass within the central kpc and scale radius are, respectively, twice and half of the actual values. We thus strongly argue against using terminal velocities or the velocity curve from the TP method for modelling the mass distribution of the Milky Way. (abridged)

Characteristics of Animal Shoulder Models for Rotator Cuff Experiments

Animal shoulder models are important in the investigation of the natural history of various pathologic conditions and for evaluation of the effectiveness of different treatments and biomaterials. The characteristics of animal shoulder models that may be used for rotator cuff related experiments are different with regard to the anatomy, behavioral pattern, advantages and disadvantages in application to each other. The lower primates and all the non-primate species, except the tree kangaroo, were neither functional overhead nor had a true rotator cuff. Utilizing more advanced primates, or perhaps even the tree kangaroo would be ideal and the most relevant to man as they possess a true rotator cuff. However, ethical concerns, costs, and many limitations in obtaining primates generally preclude the use of these animals for such research. Finally we should consider the differences in comparative anatomy and behavioral pattern of each animal model during performance or interpretation of rotator cuff experiments.

Bogus Visual Feedback Alters Onset of Movement-Evoked Pain in People With Neck Pain

Pain is a protective perceptual response shaped by contextual, psychological, and sensory inputs that suggest danger to the body. Sensory cues suggesting that a body part is moving toward a painful position may credibly signal the threat and thereby modulate pain. In this experiment, we used virtual reality to investigate whether manipulating visual proprioceptive cues could alter movement-evoked pain in 24 people with neck pain. We hypothesized that pain would occur at a lesser degree of head rotation when visual feedback overstated true rotation and at a greater degree of rotation when visual feedback understated true rotation. Our hypothesis was clearly supported: When vision overstated the amount of rotation, pain occurred at 7% less rotation than under conditions of accurate visual feedback, and when vision understated rotation, pain occurred at 6% greater rotation than under conditions of accurate visual feedback. We concluded that visual-proprioceptive information modulated the threshold for movement-evoked pain, which suggests that stimuli that become associated with pain can themselves trigger pain.

Restoration of the anatomic position during a meniscal allograft transplantation using pre-existing landmarks.

Accurate sizing and positioning of a meniscal allograft is an important factor for successful outcomes of meniscal allograft transplantation. The objectives of this study were (1) to search a proper rotational landmark, (2) to determine the sagittal slope of meniscus, and, thus (3) to determine the meniscal positioning. A total of 121 consecutive patients who underwent magnetic resonance imaging in the 3months prior to the beginning of the study were selected. To assess the meniscal rotation, rotation 0° line of the meniscus was defined as a line connecting the center of the anterior and the posterior horn of the medial and lateral meniscus, respectively. At this level, four possible reference lines were compared: Akagi line, line perpendicular to the largest mediolateral dimension (LMLD), line between the medial border of the patellar tendon and the apex of the medial tibial spine (PTMS), and line between the lateral border of the patellar tendon and the apex of the lateral tibial spine. To assess the meniscal slope, the slope of the insertional area, meniscal and bony slopes at the mid-plateau area were compared. Akagi line was significantly different with a true meniscal rotation (line connecting between centers of the anterior and posterior horns) in both medial and lateral meniscus (p<0.01 and p<0.01). LMLD was significantly different in the lateral meniscus (p<0.01), however, no statistical difference was observed in the medial meniscus (n.s.). PTMS was not different in the medial meniscus (n.s.), however, it was different in the lateral meniscus (p<0.01). On the medial side, significant statistical difference was observed between insertional and bony slope (p<0.01) and between meniscal and bony slope (p<0.01). On the lateral side, comparison of three slopes showed significant statistical differences (p<0.01-p=0.03). Line between patellar tendon and tibial spine was a good reference line for a meniscal rotation in the medial meniscus. Among previously introduced reference lines, LMLD showed approximity with a true meniscal rotation. The slope between tibial insertion and mid-portion was significantly different in the lateral meniscus.

Maxillary Molar Intrusion Evaluation using Mini-implants along with Transpalatal Arch Bar

ABSTRACTAimThe prospective clinical study was undertaken to evaluate the amount of maxillary molar intrusion achieved during orthodontic treatment using mini-implants along with transpalatal arch bar.Materials and MethodsThe treated group consisted of 10 subjects having over-erupted maxillary molars with mean age of 20.75 years. Mini-implants of 8 mm length and 1.3 mm diameter (Dentos-Absoanchor, Dentos Inc., Korea) were placed in the inter-radicular region between the second premolar and first molar on the buccal side where the molar intrusion was planned. Transpalatal arch bar was placed 5 mm away from the palate. Intrusive force of 100 to 150 gm was applied using prestretched elastic chain. Lateral cephalograms were taken before beginning of molar intrusion and 3 months after the molar intrusion. The intrusion was measured from the distobuccal cusp tip of maxillary first molar to the true vertical and rotation of the mandibular plane was assessed in relation to Go-Me and SN plane. The mean changes in the cephalometric parameters were subjected to paired t-test to determine results under statistical evaluation.ResultsStatistically significant (p &lt; 0.001) amount of molar intrusion was achieved following the usage of mini-implant with a mean value of 1.95 mm and significant anti-clockwise rotation of the mandibular plane (Go-Me) in relation to SN plane (p &lt; 0.001) was seen as a result of molar intrusion.ConclusionThe study revealed that mini-implant served as an efficient source of anchorage for achieving maxillary molar intrusion in correction of malocclusion in vertical dimensions.How to cite this articleGupta G, Rozario JE, Patil AK, Singh RK, Kannan S, Gupta A. Maxillary Molar Intrusion Evaluation using Mini-implants along with Transpalatal Arch Bar. J Contemp Dent 2015;5(3):158-164.

Geometry, amount, and sequence of thrusting in the Subalpine Molasse of western Austria and southern Germany, European Alps

In this paper we review the structure of the most external thrust belt of the Alps between the Rhein valley and Salzburg based on a new tectonic map and the (re)interpretation of seismic sections. Specifically we address the correlation between deformation in the Subalpine Molasse and the Alpine thrust belt in general and focus on the control of sedimentary facies on the structural style. A dramatic change in architecture from a ramp-flat structure to buckle folding is related to a change from coarse-grained fans to fine-grained deposits within the Subalpine Molasse. Additionally the interaction of escape tectonics with postcollisional shortening controls the decrease of late Early Miocene and younger shortening within the Subalpine Molasse from 50 km near the Rhine valley to almost zero near Salzburg. Transfer of shortening into the hinterland, which is the zone of lateral escape, ended foreland propagation of the Alpine thrusts and initiated a general break-back sequence of thrusting. Throughout this time the thrusts remained active. In such a scenario, tectonic units on top of the Subalpine Molasse are expected to undergo clockwise rotation around vertical axes. As thrusting in the Subalpine Molasse is closely related to contemporaneous transport and shortening within the tectonically higher Helvetic thrust sheets, amounts of Miocene differential shortening and related clockwise vertical axis rotation are minimum amounts. True clockwise vertical axis rotation is probably larger than the 12° deduced from the Subalpine Molasse thrust belt.

Size effects on nanomechanical behaviors of nanoelectronics devices based on consistent couple-stress theory

The paper presents the size-dependant mechanical behavior of the carbon nanotube-based nano-electromechanical systems using the consistent couple-stress theory. The formulation of the Euler–Bernoulli beam model applied in mechanical modeling of the carbon nanotubes is developed via considering true continuum kinematical displacement and rotation. This is done to solve the indeterminacy of the spherical part of the couple-stress tensor and the appearance of the body couple in the constitutive equation of the force–stress tensor of the original coupe stress theory. The governing equations are solved in order to obtain the size-dependent amount of deflection and pull-in voltages of the carbon nanotubes under electrostatic actuation. The results are provided for various dimensions and boundary conditions. Moreover, the influences of couples-stress theory on the outcomes are scrutinized. The comparison between the results obtained from the classical and couple stress theory reveals that application of the latter leads to a model of the CNT with higher stiffness, smaller deflection and larger pull-in voltages.

Mandibular rotation revisited: What makes it so important?

Orthodontists have long been aware that mandibular rotation takes place during growth, but most have underestimated its importance. This is so because the distinction between the true rotation and the rotation of the mandibular plane is typically not made. Traditionally, orthodontists have focused on the mandibular plane, which changes little because modeling on the lower mandibular border largely hides the true rotation that occurs. Furthermore, orthodontists must understand that changes in tooth position—over which they have great control—play an important role in determining the true rotational changes that occur. Such an appreciation is of particular importance when evaluating Class II cases, for which true rotation is critically important, in terms of both the development and solution of the problem. Clinically, they must be aware of and able to use the various centers of rotation to prevent deleterious changes from occurring and to orthopedically correct the problems that have developed. Orthodontists must understand that true rotation is the primary determinant of chin position and a major determinant of condylar growth direction, mandibular modeling, and dentoalveolar compensations. They must learn how to take advantage of the mandible's capacity to adapt to rotational changes.

On the maximum amplitude of harmonics of an asteroid lightcurve

Most asteroid lightcurves are dominated by the second harmonic of the rotation period, caused by elongated shape. However, if the shape is not very elongate, other harmonics may dominate, leading to ambiguity of which is the true rotation period. We argue from geometry that at low phase angle, harmonics other than the second with amplitude exceeding ∼0.4 magnitude are nearly impossible, so lightcurves with larger amplitude than that suggest a unique period dominated by the second harmonic, unless the spin is complex, non-principal axis rotation. On the other hand, lightcurves with amplitude less than 0.2–0.3 magnitudes can be dominated by other harmonics, especially the 4th and 6th, so the period may be ambiguous unless odd harmonics can be found to identify the true rotation period. We present examples of each, low and high amplitude ambiguities.

The long‐term steady motion of Saturn's hexagon and the stability of its enclosed jet stream under seasonal changes

AbstractWe investigate the long‐term motion of Saturn's north pole hexagon and the structure of its associated eastward jet, using Cassini imaging science system and ground‐based images from 2008 to 2014. We show that both are persistent features that have survived the long polar night, the jet profile remaining essentially unchanged. During those years, the hexagon vertices showed a steady rotation period of 10 h 39 min 23.01 ± 0.01 s. The analysis of Voyager 1 and 2 (1980–1981) and Hubble Space Telescope and ground‐based (1990–1991) images shows a period shorter by 3.5 s due to the presence at the time of a large anticyclone. We interpret the hexagon as a manifestation of a vertically trapped Rossby wave on the polar jet and, because of their survival and unchanged properties under the strong seasonal variations in insolation, we propose that both hexagon and jet are deep‐rooted atmospheric features that could reveal the true rotation of the planet Saturn.

The Morphological Characteristics, Growth, and Etiology of the Hyperdivergent Phenotype

Due to the skeletal complexity of the problem, hyperdivergent retrognathic patients are among the most difficult for orthodontists to treat. It is imperative to treat these patients for both esthetic and functional reasons. Hyperdivergent growth patterns are generally established early and most do not improve over time. The etiology appears to be environmental, due to postural adjustments related with compromised airways and weak masticatory musculature. If a lowered mandible posture is maintained in growing subjects, the dentition, dentoalveolar complex, and the mandible should be expected to compensate. Dentoalveolar heights should be expected to be excessive (i.e., supraeruption of the teeth), the ramus is shorter, the gonial angle is larger, the mandibular symphysis is taller and thinner, the mandibular plane is steeper, the mandible is retrognathic, and anterior lower face height is increased. Moreover, the jaws, especially the upper, are narrow. The most important factor underlying these developmental adaptations is true mandibular rotation. Rotation is important because it is the major determinant of the anteroposterior (AP) chin position. The detrimental skeletal changes that characterize hyperdivergent patients are ultimately due to backward or less than average true forward rotation. Theoretically, a therapeutic treatment that mimics normal growth (i.e., one that builds in true forward rotation) is desirable because it might be expected to correct not only the anteroposterior (AP) and vertical position of the chin, but also many of the other morphological maladaptations associated with the hyperdivergent retrognathic phenotype.