Elevation Research Articles

Differences in Accuracy of Absolute and Comparative Performance Appraisal Methods

The primary question of this experiment was whetherabsoluteandcomparativeperformance appraisal ratings differ in terms of four components of accuracy: differential elevation (DE), differential accuracy (DA), elevation (EL), and stereotype accuracy (SA). Becausecomparativeperformance appraisal methods often useglobalitems (overall performance dimensions), whereas certainabsoluteperformance appraisal methods utilizespecificitems (critical incidents), the effect ofspecificversusglobalitems was also investigated. Eighty participants viewed four videotaped lecturers and rated their performance 24 h later with bothabsoluteandcomparativeperformance appraisal methods which used bothspecificandglobalitem-types. No advantages were associated with theabsoluterating method, however,comparativeratings were more accurate thanabsoluteratings with respect to DA and SA.Globalitems resulted in greater DE and EL accuracy than didspecific;however, the converse was true with respect to DA and SA accuracy. Implications for the practice of performance appraisal are discussed.

Electromyographic analysis of the glenohumeral muscles during a baseball rehabilitation program

Many exercises are used to strengthen the glenohumeral muscles, but there have been limited studies to evaluate the exercises. Thus, the purpose of this study was to decide how the muscles responsible for humeral motion can best be exercised in a rehabilitation program for the throwing athlete. Dynamic, fine wire, intramuscular electromyography was carried out in 15 normal male volunteers performing 17 shoulder exercises derived from a shoulder rehabilitation program used by professional baseball clubs. The four rotator cuff muscles were studied, as well as other positioners of the humerus, including the pectoralis major, latissimus dorsi, and three portions of the deltoid. The electromyographic activity was synchronized with cinematography and averaged over 30 degrees arcs of motion. An exercise was considered to be a significant challenge for a muscle if it generated at least 50% of its predetermined maximum contraction over three consecutive arcs (i.e., a 90 degrees range). Four exercises were consistently found to be among the most challenging exercises for every muscle. These shoulder exercises consisted of 1) elevation in the scapular plane with thumbs down, 2) flexion, 3) horizontal abduction with arms externally rotated, and 4) press-up. This study documents that the minimum for an effective and succinct rehabilitation protocol for the glenohumeral muscles would include these exercises.

Direction-dependent spectral properties of cat external ear: New data and cross-species comparisons

Free-field to eardrum transfer functions were measured in anesthetized cats inside an anechoic chamber. Direction-dependent transformations were determined by measurement of sound-pressure levels using a small probe tube microphone surgically implanted in a ventral position near the tympanic membrane. Loudspeaker and probe microphone characteristics were eliminated by subtraction of the signal recorded in the free field with no animal present. Complexities of the transfer function, which include the presence of prominent spectral notches in the 8- to 18-kHz frequency region, are due primarily to the acoustical properties of the pinna. Differential amplification of frequency components within the broadband stimulus occurs as a function of source direction. Spectral features vary systematically with changes in both elevation (EL) and azimuth (AZ). The contrast between a notch and its shoulders is enhanced in the interaural spectral records. Spectral data from single source locations and spatial data for single frequencies at many locations are presented and comparisons with other species are drawn. It is suggested that spectral features in the 8- to 18-kHz region provide some of the necessary spectral information for sound localization and that the contrast in spectral energy between the frequencies at the notch and its shoulders is a potential directional cue.

Telerobotics: Display, control, and communication problems

An experimental telerobotics (TR) simulation is described suitable for studying human operator (HO) performance. Simple manipulator pick-and-place and tracking tasks allowed quantitative comparison of a number of calligraphic display viewing conditions. An enhanced perspective display was effective with a reference line from target to base, with or without a complex three-dimensional grid framing the view. This was true especially if geometrical display parameters such as azimuth (AZ) and elevation (EL) were arranged to be near optimal. Quantitative comparisons were made possible utilizing control performance measures such as root mean square error (rmse). There was a distinct preference for controlling the manipulator in end-effector Cartesian space for our primitive pick-and-place task, rather than controlling joint angles and then, via direct kinematics, the end-effector position. An introduced communication delay was found to produce decrease in performance. In considerable part, this difficulty could be compensated for by preview control information. That neurological control of normal human movement contains a sampled data period of 0.2 s may relate to this robustness of HO control to delay.

A Basic study of the deglutition reflex mechanism

The purpose of this investigation is to elucidate the morphological and physiological aspects of the deglutition reflex. Two different procedures were used for this study: 1) microscopic and electronmicroscopic observations of the receptors in the human and feline larynges, 2) simultaneous recordings of electromyogram of 8 selected muscles, i. e., the cricothyroid, thyroarytenoid, posterior cricoarytenoid, mylohyoid, geniohyoid, hyopharyngeal, thyropharyngeal and cricopharyngeal muscles, with polygraphic recordings of laryngeal movement and subglottal pressure during deglutition elicited by water pouring into the pharynx of a cat. On the basis of the results, the following conclusions appear to be justified. 1) Free endings were found in the mucosa of the epiglottis in the feline. 2) Free endings and corpuscular endings were observed in the mucosa of the epiglottis in the human. 3) Free endings were observed in the mucosa of the arytenoid region and vocal fold in the human. 4) Electronmicroscopically, the receptor in the human was found to be adjacent to the basal cell layer of the epithelium with a partially uncapusulated portion. 5) The intrinsic and the extrinsic laryngeal muscles are activated with a highly constant pattern in each deglutition. 6) Subglottal pressure rises before laryngeal elevation, temporarily drops during laryngeal ele vation and rises again during downwards movement of the larynx. This pattern is not affected by resection of the unilateral recurrent laryngeal nerve.

On the Possibility of One-meter-depth Temperature Survey in Indonesia Jawa and Taiwan

The possibility of application of one-meter-depth temperature measurement for investigating groundwater vein streams in Jawa and Taiwan was examined by measuring one-meter-depth temperature and temperature of flowing groundwater in some landslide areas in both countries on April 1982.As a result of this investigation, next matter are shown:1) Normal one-meter-depth temperature (θu) and temperature of flowing groundwater (θw) are influenced by elevation and latitude in Japan, but both temperature in Jawa and Taiwan are influenced only by ele vation of each investiaated area. The relation between θu and θw was shown in Table-3.2) Converted values into elevation of zero meter of θu are 29.8°C in Jawa and 25.3°C in Taiwan and the values of θw are 26.3°C in Jawa and 22.6°C in Taiwan. These values in both countries are very higher than those in Japan. θu and θw in both countries lower 0.5°C per 100 meters. This fall rate is a little lager than that of Japan on April (0.45°C/100m).3) Difference between θu and θw is 2.7-4.2°C in Jawa and 0.9-3.5°C in Taiwan in this investgating time. Application of investigation by measuring of one-meter-depth temperature is possible in every landslide areas in J awa, but this application is not possible in a part in Taiwan.4) The effectiveness of this investigating methode was shown at Cianjur Seratan in Jawa and Jiau Lin Pyng and Lung Tan in Taiwan (Figs. 8 and 9).

Effect of Tumor Promoters on Cell Kinetics in Mouse Epidermis

Tumor promoters (Tween-60 and croton oil) were applied on normal mouse skin and skin initiated by 7,12-dimethylbenz[a]anthracene a month previously. The proliferative response in treated epidermis was estimated by the use of autoradiography with 3H-thymidine. The number of cells synthesizing DNA in the basal layer increased 12 hours after application of tumor promoters and was highly elevated for 72 hours. DNA-synthesizing cells also appeared among mature cells. The labeling index for basal cells in initiated epidermis was significantly higher than in normal epidermis 12–16 hours after application of tumor promoters. During the period of active proliferation, the mitotic cycle, as estimated by the method of labeled mitoses, was 10 hours, both in normal and initiated epidermis, i.e., 8 times shorter than in normal, unstimulated epidermis. Cell maturation, as measured by transition of labeled cells from the basal layer into the layer of spinous cells, was accelerated in the epidermis stimulated by tumor promoters. Cell number/1 mm of epidermis did not change significantly during the first hours after application of tumor promoters, but rose thereafter because of elevation in the number of mature cells. This el evation tended to be more pronounced in initiated skin. It is hypothesized that the action of tumor promoters on initiated epidermis leads to the selection of cells with shortened G1 phase, which may be associated with weakened response to the factors regulating cell proliferation.

Radiological Assessment of Left Atrial Size in Infants

IN ADULT cardioroentgenology, evaluation of selective enlargement of the left atrium rests upon many findings. These include visualization of a double density along the right cardiac border, localized prominence in the “cardiac waist” on the left just below the prominence normally occupied by the main pulmonary artery segment (2), obliteration of the aortic pulmonic window, eleva tion of the left main-stem bronchus, and the selective displacement of the esophagus on the cardioesophagram. Application of the adult criteria of left atrial enlargement in the examination of children under two and a half years of age presents serious difficulties familiar to most pediatricians and pediatric radiologists (4). This is not well clarified in the literature except for passing mention of “false left atrial enlargement” (3). In infants (children under two and a half years of age will be referred to as infants in this report), the double density on the right cardiac border is frequently seen in the normal. An enlarged left atrium is more likely to compress the left main-stem bronchus than elevate it. Therefore, cardioesophagography remains the only accurate method of detecting left atrial enlargement in this age group (short of angiocardiography) and requires critical evaluation. Our purpose is to emphasize the criteria for left atrial enlargement in these infants. Materials and Methods One hundred and twenty esophagographic studies, performed in infants for extracardiac reasons, were reviewed. The supine position was used in all cases. Thirty-six of the 120 examinations were selected for analysis because multiple “spots” of the well filled esophagus had been recorded in each instance. In 19 of the 36, segmental indentation on the esophagus suggesting left atrial enlargement was noted on more than one of the spot-films. In 4 a single spot-film recorded localized indentation, and in 13 no localized indentation was noted on the spot-films. Subsequently, 25 children with no heart disease were subjected to cine-esophagography. Analysis of the frames in each study revealed segmental esophageal indentation, varying from 3 to 25 per cent of the frames. In addition, cine-esophagrams were obtained in 25 children with varying congenital heart lesions. In these, independent evaluation of the left atrial size was made from angiocardiography, electrocardiography, and the physiologic data recorded during cardiac catheterization. Discussion The infant's chest is proportionately shorter and wider than the adult's (5), and in infants the general size and configuration of the heart change from inspiration to expiration considerably more than in adults. Segmental esophageal indentation by a normal left atrium occurs when expiration and atrial diastole coincide. The size of the indentation or the esophageal curve varies during the expiratory event.

Instrument for determining and equalizing forces applied to individual teeth by alignment arches and otherwise

T E application of force in orthodontic treatment has always been more or less haphazard, and limit ed chiefly by the fortitude of the patient. Since studies have been made by several researchers with a view to determining what takes place in the supporting tissues during tooth movement, it has become evident that orthodonti c procedures should be placed upon a more rational basis and the forces applied should be limited to what those students have indicated is the range of biologic tolerance. Among the first to attempt to measure the amount of force to be applied to a tooth, so far as I have been able to discover , was J oseph E . J ohnson, who made use of a modified postal scale for measuring the pressure requi red to bring an alignment wire into the bracket of a band on the tooth to be moved. Another tension tester was introduced by J . E. Robinson ; this consisted of a simple cylindr ical spr ing scale, one end of which could be used to measure the push tension, and the other the pull tension on a wire . This device was adapted for use not only on labial align ment wires, but also on th e auxilia ry spr ings of a lingual or palatal appliance. Neither of these devices could be depended upon to give reliable information where more than one toot h was to be attached, because with the at tachment of each succeeding tooth , those first att ached would have th eir tension increased owing to the decreased distan ce between th e fixed points (anchor teeth ) and the points of attachment of each additional tooth included. The instrument under consideration here is designed to provide a means by which one may measure th e tension to be applied to every tooth in malposition, equalizing it so that every tooth may be subjected to a similar and known amount of stress, regardless of whether it be push or pull, elevat ion, depression, torsion, or the power to be obtained from torque in the wir e. A brief descri ption of the instrument and th e mode of operat ion follows. Upon a base consist ing of a flat metal plat e (F ig. 1) is arranged a ser ies of threaded holes (a) in the genera l form of an arch, in to which are screwed split stubbs (b b b) which suppor t swivels (c) which telescope them and may be raised or lowered. These swivels carry friction rings (d) through which are passed the cylinders of the tubular spring scales, the sliding rods of which are provided with a prong at one end and a hook at the other.