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Background Although structural leg length discrepancy is a physical problem that affects all populations, its measurement and correction is difficult. Objectives The purpose of this study was to investigate the effect of using a shoe insert for correcting mild structural leg length discrepancy on frontal and transverse plane spino-pelvic alignment and dynamic balance. Study design Pre-test post-test control group design (randomized controlled study). Methods Thirty one patients with structural discrepancies of 5–20 mm were randomly divided into two groups, those who used a shoe insert (group(A)) and those who formed a control group (group(B)). Their mean age, mass, and height were 31.5 ± 10y, 77.8 ± 10.4 kg, and 1.69 ± 0.08 m respectively. Spino-pelvic alignment measures (pelvic tilt, pelvic torsion, surface rotation, and lateral deviation) were assessed using rasterstereography, while dynamic balance was assessed using Star Excursion Balance Test (SEBT). Patients were assessed pre- and post-intervention over the eight-week study duration. Results Mixed Design MANOVA showed significant decreases in the mean values of all spino-pelvic alignment measures and significant increases in the mean (SEBT) scores with insert use (p Conclusions Using shoe insole for leg length discrepancy correction appears to assist in improving postural symmetry and dynamic balance. (Clinical trial registry www.pactr.org number PACTR201611001888975). Implications for practice • Insert use for LLD correction may assist with improving spinal alignment. • Insert use for LLD correction may assist with improving pelvic alignment. • Insert use for LLD correction may assist with improving dynamic balance.

Leg length inequalities (LLI) are a common problem in medicine. So far, the diagnosis and treatment are performed under static conditions. Surface Topography (ST) is an optical, non-invasive technique that uses the principle of triangulation to measure spinal posture and pelvic position. This technique offers the opportunity to detect and treat LLIs and their effects under dynamic conditions.question The aim of the study is to show that ST can detect simulated LLIs under dynamic conditions and to prove if there are differences between the effects on the human body under static and dynamic conditions.In the clinical study a total of 30 test subjects were examined with a ST measuring device. LLIs (1 to 4 cm) were simulated using a custom- built sandal and insoles of various thickness. The pelvic obliquity, the surface rotation and lateral deviation of the spine were detected on a treadmill under static and dynamic conditions (3 km/h).Under static and dynamic conditions LLIs lead to a significant increase of all measured parameters. The pelvic obliquity reaches a significant level of p 0.0001 under static and p = 0.0001-0.0421 under dynamic conditions. However, for all examined parameters the magnitudes of the parameters under dynamic conditions were smaller than under static conditions.The study showed that simulated LLIs also have a significant effect on the human pelvis and spine under dynamic conditions, but with a smaller magnitude than under static conditions. The human individuum is a dynamic one. Because of that, for the future it should be of great interest to use dynamic measurements to detect and treat LLIs to provide an over correction of LLIs.

Objective Patellar instability (PI) represents various underlying pathologies, including patellar malalignment. Continuous patellar alignment develops to patellar tracking and is regarded as the end product of combined predisposing factors. We quantitatively investigated the inhomogeneity of patellar tracking in PI. Methods Sixty knees of 56 patients with PI and 15 knees of 10 healthy volunteers (HVs) were studied. Three-dimensional (3D) computer models were created based on MRIs at 10° intervals over 0°–50° of flexion, and patellar tracking was quantitatively analysed using patellar 3D shift. Classification was performed according to the maximum 3D shift (max-shift), indicating the extent of lateral deviation, and the change of 3D shift from 0° to 50° (change0–50), indicating movement direction. First, the cut-off value (COV) of the max-shift was defined based on the data from HVs. When a value was greater than the COV, it was defined as a major subluxation, and when the value was smaller it was defined as a minor subluxation. Next, the two COVs of change0–50 were similarly defined. When a value was greater than the upper COV, it was defined as a major-lateral type, laterally moving the patella with flexion, and when smaller than the lower COV it was defined as a major-medial type, medially moving the patella with flexion. When a value fell between the two COVs, it was defined as a major-straight type. Results Fifty-three patellae (88%) with values larger than the COV of the max-shift (mean +1 SD of HV) were defined as major subluxations and seven (12%) showing smaller values as minor subluxations. Among the major subluxations, 25 (42%) showing a smaller value than the lower COV of change0–50 (mean –2 SD of HV) were defined as major-medial type, while 7 (12%) showing a larger value than the upper COV of change0–50 (mean +2 SD) were defined as major-lateral type. Twenty-one (35%) were defined as major-straight type. No further analysis was performed on the seven minor subluxations (the minor type). Conclusion PI was quantitatively classified into four types according to the extent of lateral deviation and the movement direction of the patellae with flexion, showing inhomogeneity of patellar tracking.

Hallux valgus is a common condition that results in lateral deviation of the hallux and medial deviation of the metatarsal. When conservative management fails, surgical management is often necessary. More than 150 procedures have been described, and most recommend an open approach. More recently, a minimally invasive approach to bunion correction has gained popularity among surgeons. The authors have been performing a minimally invasive percutaneous method of bunion correction with positive outcomes. This article presents case examples and a systematic approach for correction of this common foot condition.

Introduction The relationship between molar occlusion and chewing patterns was examined in subjects with laterally deviated mandibles. Methods Twenty-three patients with mandibular deviation from the midline (4 mm or more) and skeletal Class I (0° ≤ANB ≤4°) were divided into 2 groups: normal bite and crossbite. The chewing pattern was classified as normal, reversed, or crossover. Results The normal bite group had a normal chewing pattern on the affected side 100% of the time and a reversed chewing pattern on the affected and unaffected sides 0% and 7.2% of the time, respectively. Additionally, the normal bite group showed no evidence of a crossover chewing pattern and also had significantly less axial inclination of the mandibular teeth on the affected side compared with the crossbite group; lingual inclination was also evident. The crossbite group had a normal chewing pattern on the affected and unaffected sides 0% and 55.6% of the time, respectively, and reversed and crossover chewing patterns on the affected side 55.6% and 44.4% of the time, respectively. Conclusions A normal chewing pattern tends to result in lingual axial inclination of the mandibular molars on the affected side, as well as a more consistent chewing pattern.

Holding an asymmetrical load, like a rucksack, grocery bag, or travel backpack, is a part of daily and occupational activities. This pilot study was aimed to determine the effects of light, asymmetrical, handheld load on the body posture and foot pressure distribution in young adults. Thirteen young volunteers, free of any injury or pain, took part in the study (aged 21.53 ± 1.10 years). All the study participants were right-handed. An additional load (4 kg, placed in the rucksack) was asymmetrically held in each hand while standing still. For evaluation of the posture and foot pressure distribution, the investigation focused on three positions, i.e., no-load, a rucksack in the right hand, a rucksack in the left hand. We used a surface topography system and force platform for evaluation of the body posture and foot pressure examination, respectively. The results showed that the main changes in the body posture caused by an external load application manifested in trunk imbalance. The trunk was shifted in the direction opposite to the load. Trunk imbalance changes were statistically significant in all three comparisons (p = 0.001). Interestingly, changes in the rotations and lateral deviation seem to be dependent on the hand dominance. Greater foot pressure was observed on the loaded limb (p

The paper proposes the design methodology of a new auto-landing system for unmanned aerial vehicles (UAVs) with variable centre of mass subject to wind shears, wind gusts, and atmospheric turbulences. Starting from the UAV nonlinear dynamics, a new control architecture is developed. It combines the backstepping and dynamic inversion approaches for the control of UAV attitude angles, lateral deviation from runway, flight altitude, and forward speed during the three landing stages (final approach, glide slope, flare). The estimation of the wind shears, wind gusts, and atmospheric turbulences is achieved via a neural network based disturbance observer, included in the new auto-landing architecture. By its software implementation and validation, the robustness to wind type disturbances and the stability of the new auto-landing system are proved. There are cancelled the altitude error, the lateral deviation from runway, while the UAV trajectory is the desired one with continuous and smooth transition from one stage of landing to another.

Data from 15 jewellery students, in their 1st and 3rd years of training, were analysed to show how data collected from work settings can be used to objectively evaluate performance in the use of tools. Participants were asked to use a piercing saw to cut 5 lines in a piece of metal. Performance was categorised in terms of functional dynamics. Data from strain gauges and a tri-axial accelerometer (built into the handle of the saw) were recorded and thirteen metrics derived from these data. The key question for this paper is which metrics could be used to distinguish levels of ability. Principal Components Analysis identified five components: sawing action; grasp of handle; task completion time; lateral deviation of strokes; and quality of lines cut. Using representative metrics for these components, participants could be ranked in terms of performance (low, medium, high) and statistical analysis showed significant differences between participants on key metrics.

Golfers' swings vary with each individual and golf club manufacturers provide the service called “Fitting”, to select an appropriate golf club for each swing, to an each golfer. In order to find the appropriate golf club for each golfer, it is necessary to measure the position and orientation of a golf club head. It can be supposed that the measurement error needs to be less than 0.5 degree. There is an existing method whereby the three-dimensional (3D) orientation of a golf club head is measured from the 3D positions of points on the golf club head. This method is generally used in the area of motion analysis, and has problems in that the system has many restrictions in its installation, large installation space is required, and costs are incurred to the future expansion of the fitting service to many locations, as two or more cameras are needed. The “Fitting” service requires a method that needs small space, low cost and little calculation time. Therefore, A method was developed, whereby the 3D orientation of a golf club head was calculated based on one image from just one camera using the Newton-Raphson method, which needs little calculation time, and the measurement accuracy was validated compared with the experimental results. It was proved that the developed method is useful to a golf club fitting service because the measurement error is less than 0.5 degree of our target even when various golfers' swings are measured, whereby markers are attached possibly near the outline of the head in the case of the farthest distance between markers from 80 to 95 mm, and then the coordinates of the marker center are identified by calculation from luminance and coordinates of each pixel in an area surrounding the marker.

Background When performing minimally invasive spine surgery in trauma patients, a short operation time and a perfect positioning of pedicle screws are demanded. In this study, we show that a Minimally Invasive Pedicle Screw System allows both. Methods One hundred and twenty-one patients (131 fractures) with fractures between Th 3 and L 5 were treated. The most common fracture type was A3. We treated 52 females and 69 men with a mean age of 56.7 years. In 72% of the cases, the procedure was performed by two experienced spine surgeons. Postoperatively, all patients were examined using a CT-scan. In 61 patients, an anterior stabilization was additionally performed in 33 patients, vertebroplasty or cyphoplasty was performed. Fifteen patients underwent laminectomy. Results No patient postoperatively developed any additional neurological compromise. In total, 682 screws were placed. In the postoperative CT-scan, we found 16 screws (2.2%) in suboptimal position, 8 with medial and 8 with lateral deviation. Discussion With the Minimally Invasive Pedicle Screw System used in this study, spinal fractures can be treated in a short operation time with percutaneous stabilization and a correct positioning of the pedicle screws in almost 98%. In our study, no screw was so much malpositioned that revision surgery would have been necessary. Level of evidence Level III – Case-control study.

A three dimensional dynamic model is used to estimate the best rebounding position for players in basketball. The model has six distinct sub-models: flight, and ball-contact sub-models of ball-rim, ball-bridge, ball-board, ball-bridge-board, and ball-rim- board contact. It allows both slipping and non-slipping interactions at the ball-contact point. Using probabilistic selection of release velocity, angle, and lateral deviation angle, simulations analyse ball trajectories and good rebounding positions for players. Our estimation includes player wingspan. We analyse the relationship between the most likely player rebound positions and ball rebound positions with high probability. The best player rebound position is usually different from the most likely ball rebound position. Player rebound regions for players with large wingspans are very close to the hoop and include some likely ball rebound positions. For short-range shots, one player is able to collect almost all of rebounding balls but two or three rebounders are required for long-range shots.

This paper investigates the influence that different unsteady aerodynamic components have on a vehicle's handling. A simulated driver and vehicle are subject to two time-dependent crosswinds, one representative of a windy day and the second an extreme crosswind gust. Initially a quasi-static response is considered and then 5 additional sources of aerodynamic unsteadiness, based on experimental results, are added to the model. From the simulated vehicle and driver, the responses are used to produce results based on lateral deviation, driver steering inputs and also to create a ‘subjective’ handling rating. These results show that the largest effects are due to the relatively low frequency, time-dependent wind inputs. The additional sources of simulated unsteadiness have much smaller effect on the overall system and would be experienced as increased wind noise and reduced refinement rather than a worsening of the vehicle's handling.

This case report describes a new surgical orthodontic approach involving alveolar bone distraction osteogenesis for correction of an asymmetric maxillary dental arch. The treatment was combined with conventional orthognathic surgery to improve the mandibular lateral deviation. This new treatment strategy produced an ideal dental arch and a symmetric facial appearance efficiently and effectively., American Journal of Orthodontics and Dentofacial Orthopedics, 143(2), pp.266-273; 2013

Basketball rebound regions are estimated using a dynamic model for short-, medium-, and long-range direct and bank shots and with previously measured standard deviations of release velocity and angle. The model includes basketball stiffness and damping, and contains flight and ball-contact sub-models. The deterministic simulations, together with random Gaussian probability density functions for release velocity, angle and lateral deviation angle, analyze ball trajectories from different shot positions. The results instruct likely rebounding positions. Angled direct and bank shots from the same release position usually have two high-probability rebound positions, one on the same side as and one on the opposite side from the shooter. The highest probability rebound position is typically in or near the optimal shot path plane for capture. Rebound positions from skilled player's shots are usually more predictable.

A three dimensional dynamic model is used to calculate basketball motions for field shots with release conditions: release position, release velocity, backspin angular velocity, release angle, and lateral deviation angle. The model includes basketball stiffness and damping and calculates the slipping and non-slipping, and spinning and non spinning motions at the ball-contact point. The simulations, together with probabilistic selection of release conditions, analyze ball trajectories of field shots and possible rebounding positions for players. The results instruct the best rebounding position for placement of rebounders. We also investigate the effectiveness of denying the optimal shot paths for attempted blocked shots.

A dynamic model is used to analyze the rebounding ball trajectories of free throws. The dynamic model previously described calculates slipping and non-slipping, and spinning and non-spinning motions at the contact point. First ball-contact boundaries for rebounds are estimated in the release velocity and angle space. We show the geometry of ball trajectories for rebounds of free throws with lateral deviation at the release point. The distances and positions for free-throw rebounds are analyzed.

Introduction Different types of studies and radiographic parameters have been established to diagnose potential patellofemoral alterations; one of the most commonly used of these is the axial patellar view at 30°. Purpose To assess the reproducibility of patellar measurements on axial patella X-rays at 30°. Materials and methods In 23 patients we performed 2 axial X-rays of the same patella, at a fixed 30° angle; both films were obtained with the same technique, at an interval of 5min between them. The 3 most frequently used parameters were used to measure alterations in patellofemoral alignment: Laurin's lateral patellofemoral angle, Sasaki and Yagi's lateral deviation and Merchant's congruence angle. These measurements were taken by one same observer in all radiographs. A statistical analysis was made of the results, comparing each measurement on the 2 radiographs and analyzing the intraclass correlation coefficient. Results We found very good concordance levels with an intraclass correlation coefficient for the three angles studied greater than 0.90. Conclusions The technique described boasts a high degree of reproducibility.

International audience; Without vision, keeping a straight-ahead direction while stepping on the spot is almost impossible, everybody deviates more or less. Several explanations for this, such as laterality, vestibulo-spinal influence, dopamine system, have been proposed. The aims of the experiment presented here were (1) to quantify the lateral deviation when stepping using a modified Fukuda test apparatus, and (2) to determine the factors potentially underlying such deviation. Twenty-five young adults, blindfolded, performed the experiment which consisted in stepping while holding a rotating vertical roll bar fixed on the wall. Four experimental conditions (i.e., normal, with an imposed pace, dual-task, or with the neck bent) were tested. All participants deviated towards one side or the other in all conditions. Adding an attentional load or imposing a particular pace did not change the amount of deviation. For three conditions (normal, with an imposed pace and dual-task), the deviation towards one side was not significantly larger than towards the other side at the group level. In the bent-neck condition, the deviation was significantly larger than in the other conditions. Furthermore, in this condition the deviation towards the left was significantly larger than the deviation towards the right at the group level. We discussed the results regarding the role of vestibular information and proprioceptive feedback from neck muscles in correcting a spontaneous deviation. Our results, however, go against the idea that sensorimotor lateral preferences are among the factors underlying such deviations, since we found no relationship between lateral preferences (hand, foot, and eye) and the side of deviation.

We propose to extract the charge information of high energy muons in very inclined extensive air showers by analyzing their relative lateral positions in the shower transverse plane. We calculate the muon lateral deviation under the geomagnetic field and compare it to dispersive deviations from other causes. By our criterion of resolvability, positive and negative muons with energies above $10^4$ GeV will be clearly separated into two lobes if the shower zenith angle is larger than $70^\circ$. Thus we suggest a possible approach to measure the $\mu^+ / \mu^-$ ratio for high energy muons., Comment: 21 latex pages, 9 figures, to appear in Astroparticle Physics

Cell phone use among pedestrians leads to increased cognitive distraction, reduced situation awareness and increases in unsafe behavior. Performing a dual-task, such as talking or texting with a cell phone while walking, may interfere with working memory and result in walking errors. At baseline, thirty-three participants visually located a target 8m ahead; then vision was occluded and they were instructed to walk to the remembered target. One week later participants were assigned to either walk, walk while talking on a cell phone, or walk while texting on a cell phone toward the target with vision occluded. Duration and final location of the heel were noted. Linear distance traveled, lateral angular deviation from the start line, and gait velocity were derived. Changes from baseline to testing were analyzed with paired t-tests. Participants engaged in cell phone use presented with significant reductions in gait velocity (texting: 33% reduction, p=0.01; talking: 16% reduction, p=0.02). Moreover, participants who were texting while walking demonstrated a 61% increase in lateral deviation (p=0.04) and 13% increase in linear distance traveled (p=0.03). These results suggest that the dual-task of walking while using a cell phone impacts executive function and working memory and influences gait to such a degree that it may compromise safety. Importantly, comparison of the two cell phone conditions demonstrates texting creates a significantly greater interference effect on walking than talking on a cell phone. Keywords: Driver distraction; Language: en

A measurement system is discussed, suitable for measuring the lateral deviation of electrical guided vehicles. It utilises permanent magnets buried in the road. It is shown that the lateral deviation of a vehicle can be determined from the longitudinal and lateral magnetic fields. This method is insensitive for changes in the fieldstrength of the magnets and changes in vertical distance between magnet and field-sensor. It is shown that part of the errors due to slant of the magnet can be eliminated by measuring with two 2-axes sensors.

Panic agoraphobic subjects constantly struggle with the accurate registration of everyday space-time dimension. They are hindered in the exploration of their surroundings by constant self-directed attention. In our investigations we examined whether during experimental goal-directed locomotion orientation insecurity would appear. The accuracy of target-directed motion, i.e. the degree of lateral deviation, was recorded in three diagnostic groups, panic agoraphobics (15 subjects), generalized anxiety patients (15 subjects), and normal controls (15 subjects), and normal controls (15 subjects). According to our results the approach vector of the panic agoraphobics deviated to the right, while in the case of generalized anxiety patients it deviated to the left, while normal controls did not deviate significantly from the middle line. Results are compatible with previous literature which associated panic with an overactivity of left-sided functions, and generalised anxiety with an overactivity of right-sided functions.

Temporomandibular joint alterations have been associated with abnormal mandibular movements in the open/close cycles and in the laterotrusive border movements. The quantitative analysis of these movements could allow a better or earlier diagnosis for patients and offer some insight into the pathophysiology of the disorder. Maximum opening and mandibular laterotrusive border movements were studied and measured in a group of 165 patients with a considerable lateral deviation (equal to or greater than 5 mm) in maximum opening. Movements were directly performed by the patients and recorded with a mandibular kinesiograph. The slope of the lateral guidance (frontal plane projection) was measured in the first millimeters of motion and started from the maximum intercuspal position. On average, slopes were significantly flatter on the same side with the opening deviation. These slopes were significantly flatter than previously published physiologic ranges, whereas contralateral slopes were similar to normal references. The results may be explained by a correlation between the insufficient lateral protection and a temporomandibular mandibular joint dysfunction (ipsilateral low mobility).

Blade-deviated fenestrated clips developed by one of the authors were applied very successfully in 15 cases of A Com A aneurysms which corresponded to 32% of the aneurysms upon which were operated. Of the 15, 13 cases were projected superiorly, which is the most difficult and hazardous type if ruptured at the neck. The characteristic feature of the clip is the lateral deviation of occluding blades. The superiorly projecting type A Com A aneurysm is located posterolateral to the A Com A in the operative field, and the clips were extremely useful in the aneurysms in providing safer and more exact occlusion via parallel closure of the A Com A or the aneurysm neck.

Summary: A 31-year-old woman presented with a 1-year history of recurrent dislocation of the patella. On examination, she was found to have a mass at the medial patellofemoral joint line. Arthroscopy showed this to be a vascular synovial tumor extending into the medial patellofemoral joint and causing lateral deviation of the patella. The mass was resected with resolution of her symptoms and histologic examination showed this to be pigmented villonodular synovitis. There are an increasing number of case reports of these lesions causing varying mechanical symptoms in the knee and they should be considered as a differential diagnosis. Arthroscopy: The Journal of Arthroscopic and Related surgery, Vol 16, No 7 (October), 2000: pp 767–769

In this paper, the author describes a lane following assistance system (LFAS) designed to reduce the mental workload of drivers. The LFAS detects the amount of lateral deviation of a vehicle within a traffic lane. An adjustment is then made to increase steering reaction torque as the vehicle deviates away from the center of the lane. The system configuration consists of a detection camera, an image processing and control unit, electric power steering, and a yaw rate sensor.

Background When performing minimally invasive spine surgery in trauma patients, a short operation time and a perfect positioning of pedicle screws are demanded. In this study, we show that a minimally invasive pedicle screw system allows both. Methods One hundred and twenty-one patients (131 fractures) with fractures between Th 3 and L 5 were treated. The most common fracture type was A3. We treated 52 females and 69 men with a mean age of 56.7 years. In 72% of the cases, the procedure was performed by two experienced spine surgeons. Postoperatively, all patients were examined using a CT scan. In 61 patients, an anterior stabilization was additionally performed in 33 patients, vertebroplasty or cyphoplasty was performed. Fifteen patients underwent laminectomy. Results No patient, postoperatively, developed any additional neurological compromise. In total, 682 screws were placed. In the postoperative CT scan, we found 16 screws (2.2%) in suboptimal position, 8 with medial and 8 with lateral deviation. Discussion With the minimally invasive pedicle screw system used in this study, spinal fractures can be treated in a short operation time with percutaneous stabilization and a correct positioning of the pedicle screws in almost 98%. In our study, no screw was so much malpositioned that revision surgery would have been necessary. Level of evidence Level III Case-control study.

Although TMJ click is common, its relationship to subjective and objective evaluation and the position of the click within the envelope of motion is not fully understood. This study attempted to correlate these entities in 21 patients. Although specific conclusions are difficult to make from this study, the findings suggest the following: The most important etiologic factors in the click are bruxism, clenching, an occlusal slide from centric relation to centric occlusion of more than 1 mm, and lateral deviation. The most important clinical sign of TMJ clicking is palpable soreness in the lateral pterygoid and temporal muscles. Over 50% of patients with a click have bilateral click. A click occurs least often in retruded closing movement (7%) and most often in habitual movement (37%). Although it appears that closure in the retruded position may avoid click, further evaluation of the presence of click in retruded opening movement is indicated. A mean mandibular lateral deviation of 2.2 mm anteriorly is observed at the time of click.

The measurement of the magnitude of the deformity in idiopathic scoliosis is usually performed by either the Cobb method or the Ferguson method. In this study an error analysis of the Cobb method is given. The projection error is 3° and is more or less the same in moderate and severe scoliosis. The observation error is 3–5° in mild scoliosis and may increase to 10° or more in severe scoliosis. This observation error is strongly related to axial rotation of the vertebrae. Progression of the deformity in idiopathic scoliosis, either by increasing lateral deviation and/or increasing axial rotation is the indication to treatment. Because the Cobb angle is mainly influenced by the lateral deviation and less by the axial rotation, it is recommended to use, in addition to the Cobb method, an accurate method for measuring the axial rotation.

Patterns of mandibular movement and jaw muscle activity in two monkeys were recorded during mastication of natural foods before and after ablations of the lateral precentral cortex. Bilateral, but not unilateral, lesions that included the “face” area of the precentral cortex produced permanent changes in patterns of mandibular movement during mastication, including decreased jaw opening and lateral deviation. The basic chewing rate, however, was not greatly altered. Paresis of the tongue and facial muscles, possibly combined with loss of the ability to produce complex jaw movements, hindered manipulation and positioning of food required for mastication. Bilateral lesions of the far-lateral precentral cortex, a region that evokes rhythmic jaw movement when electrically stimulated, initially produced symptoms like those described above, but after a period of recovery, patterns of mastication became normal. The results indicate that the precentral cortex, particularly the face area, is involved in coordination of the tongue, jaw, and facial muscles necessary for normal, efficient mastication. At the same time, the results confirm the existence, in the nonhuman primate, of a subcortical pattern generator capable of producing a pattern of rhythmic jaw movement similar in some respects to masticatory jaw movements of normal monkeys.

The flocculus of the monkey was mapped with microstimulation methods in chronic preparations. Three types of low threshold, disconjugate eye movements were elicited: (1) a lateral deviation of the ipsilateral eye, (2) a downward deviation of the ipsilateral eye and (3) counterclockwise rotation of the ipsilateral eye. Horizontal eye movements were obtained from folia 2, 3, 4 and 6–10 of the flocculus, and the region eliciting horizontal eye movements was traced in the sagittal plane over a distance of 4 mm in one animal. However, sites flanking these horizontal movement sites produced either vertical movements, rotatory movements or failed to produce a movement of either eye. These findings suggest a zonal organization of flocculus functions in monkeys that is consistent with the differential projections of flocculo-vestibular connections revealed by retrograde tracing studies [2].

A recent study of the WKB solutions for radio wave propagation in the ionosphere has shown that the complex phase of the ith wave should include a term κ ∝ Γii dz. This has hitherto been ignored in ray tracing studies. The effect of including it is investigated and it is shown to lead to non-reversibility of the ray paths and to a small modification of the lateral deviation and bearing error. It is particularly important for frequencies less than the electron gyrofrequency in calculations that require an accurate knowledge of the phase of a wave that has traversed the ionosphere.

Any test used for the diagnosis of muscle imbalances must be accurate, precise, and quickly applicable in a large percentage of cases. It should make possible the measurement of phorias as well as trophias and should not be dependent on binocular vision. It should be applicable to very young children. The more objective the test can be made the better. The screen test with its modifications, screen-Maddox rod, and screen-comitance, are described in detail after the physiology and mechanics of the ocular movements have been briefly discussed, and cases are cited to emphasize the benefits of these tests. Cases of combined vertical and lateral deviations are described and the importance of measuring the combined deviations stressed. The tendency in some cases of lateral strabismus to a change from convergent to divergent squint, or vice versa when a vertical deviation is present, is discussed. Cases are cited in which this developed following operation for the lateral deviation, the vertical deviation having remained uncorrected. The same change in deviation has been observed when operation has not been resorted to. The screen test is the only test in the writer's experience that is applicable in all cases in which vision is sufficient for central fixation. Read before the Washington, D.C., Ophthalmological Society, January 6, 1936.

Summary 15 years' experience allows the author to state that secondary corrective plastic operations on the osseous framework, the septum and the triangular cartilage are always a must by cleft nose patients. The procedures for unilaterally or bilaterally involved nose differ, lateral deviation and asymmetry being the main deformities in the first case, and underdeveloped septum and columella and a widened nasal tip in the second. The author describes techniques which are either entirely his own, or through him modified. Diagrams and clinical cases illustrate and fully explain such techniques.

This paper describes a method of measuring the F-region gyro-frequency from P'f{hook} records, using the relation f{hook}H = f{hook}x-f{hook}z. The observed values of the critical frequencies must be corrected for errors arising from lateral deviation and horizontal gradients of critical frequency. It is shown that the lateral deviations of the O, X, and Z modes, calculated with an approximate value of f{hook}H, and the observed values of f{hook}x, f{hook}o, and f{hook};Z, provide sufficient information to obtain both the horizontal gradient of critical frequency and the gyro-frequency. The results of an analysis of P'f{hook}; records obtained at Hobart, Tasmania, are given. It was found that at a mean true height of 378 km, the mean gyro-frequency was 1.53 Mc/s, compared with an extrapolated value, using ground parameters, of 1.40 Mc/s.

The best way of being certain of the exact position of nasopharyngeal electrodes is to obtain an X-ray basal view of the skull before proceeding to the EEG examination. Lateral deviation or external rotation may produce crossing and this should be corrected before, and checked for after recording as well.

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