Showing papers by "University of Düsseldorf published in 1975"

Configural Frequency Analysis as a Statistical Tool for Defining Types.

Abstract: Configural frequency analysis (CFA) is a new method for identifying types. Types are defined as patterns (configurations) of binary variables occurring more frequently than may be expected under th...

Handedness as a function of test complexity.

Abstract: Summary.-Handedness as a function of test complexity was investigated with two tests, Dotting and Tapping-on-squares. For each one three levels of complexity were established by varying radius (Dotting) and square sides (Tapping-on-squares). Administration of the different complexity levels to a total of 310 third and fourth grade boys and girls showed that the rare of lefthandedness increased from 6% "00 16% with decreasing level of test complexity. It is concluded that optimal classi€ication of handedness is only made possible by maximal levels of test complexity, which have to be established empirically for different populations. Development of a hand-dominance-test (Steingrueber, 1971) showed that the three scales with highest retest reliabilities were Dotting (marking pencil dots into irregularly aligned circles), Tapping-on-squares (marking pencil dots into aligned squares), and Tracing (drawing a pencil line into an irregular parallel track without touching the borders). Right and left hands were tested successively with these three subscales, and scoring was based on the achievement difference of both hands and not on hand preference. The scales identified different proportions of left-handers out of the same population, namely, 2% (Dotting), 11 % (Tapping-on-squares) , and 35 % (Tracing). This considerable variation was obtained although a factor analysis of intercorrelations, still including other tests, showed all three criteria to be highly correlated with the first factor. Therefore, the different proportions of left-handers were not related to the fact that different dimensions of handedness were measured with each scale; rather it could only be a matter of positional change. In other words, the positions of Ss in relation to each other were maintained and only a shift of the zero point of the scale (defined as "equal achievement of both hands" or "ambidexterity") occurred. The consequences are of special importance for applications in this field because all research work in clinical and educational problems of handedness (cf. Hecaen & de Ajuriaguerra, 1964; Sovak, 1968) is invalidated when one test classifies only 2% and another test 35% as left-handed Ss. The following study intends to clarify the conditions of varying classifications of left- and right-handedness by analyzing the shift of the zero point of the scale. Blau (1946, p. 36 ff.) intends to explain this shift by presupposing that a test of handedness must demand a certain amount of psychomotor complexity in order to show the dominance of one hand over the other. It can therefore be assumed that in extremely simple tests both hands are equally competent. Under these conditions two not completely independent hypotheses on

A new absolute asymmetric synthesis

Abstract: Der e infache ana ly t i s che Nachwei s ge r inger S pu ren yon S 2i s t ffir F ragen des U m w e l t s c h u t z e s (Wasser u n d L u f t r e inha l t ung ) , der t e chn i schen E i g e n s c h a f t e n der Metal le u n d der Kor ros ion yon groBer B e d e u t u n g . Bet U n t e r s u c h u n g e n fiber die ka tho d ische A b s c h e i d u n g yon Silber a u s cyan i d i s chen E lek t ro ly t en in G e g e n w a r t yon S2--Ionen w u r d e beobach te t , dab s ich bere i t s S2--GehaIte yon < I p p m an t den Verlauf der Po ten t i a l s t r o m d i c h t e k u r v e n auswirken . Mit Hi l fe dieses Ef fek tes is t es mbglich, sehr ger inge S2--Gehal te in w~sser igen L 6 s n n g e n an t e infaehe Weise g e n a u zu b e s t i m m e n . I n Fig. t s ind ffir e inen E l e k t r o l y t e n m i t 80 g Silber/l [NAg (CN)2 ] u n d 200 g f re iem KCN/1 die u n t e r St ickstoff bet R a u m t e m p e r a t u r po t en t i o s t a t i s ch a u f g e n o m m e n e n ~ a t h o d e n p o t e n t i a l s t r o m d i c h t e k u r v e n wiedergegeben. Als K a t h o d e d ien te ein t c m 2 groBes Feins i lberblech . Se tz t m a n d e n E l ek t ro ly t en Na~S bis zu e iner K o n z e n t r a t i o n yon 0,06 p p m S 2zu, so t r i t t bet P o t e n t i a l w e r t e n yon e twa -0 ,6 V (gegenfiber ge sg t t i g t e r Ka lomel -Elek t rode) e in S te i l ans t ieg der S t romd i ch t e bis zu e inem M a x i m u m bet e twa -0 ,8 V u n d 1,6 A / d m ~ ein. Bet h6he ren S p a n n u n g e n f~illt die S t romd i ch t e d a n n wieder auI die W e r t e der S2--Ireien E lek t ro ly t e ab. Bet n e g a t i v e n K a t h o d e n po t en t i a lwe r t en yon fiber -0 ,9 m V ve r l au fen die Po ten t i a l s t r 0 m d i c h t e n k u r v e n ffir das SZ--freie u n d das S2--hal t ige B a d gleich. Die Abh~ng igke i t des S t r o m d i c h t e m a x i m u m s v o m S 2-Geha l t i s t a u s Fig. 1 zn e n t n e h m e n . D a n a c h e rh6hen 1,3 p p m S 2bet e i nem Po ten t i a l y o n -0 ,8 V die S t romd i ch t e gegenf~ber e inem S2--freien E l e k t r o l y t e n u m das e twa t 5fache. Die A u s b i l d u n g des S t r o m d i c h t e m a x i m u m s k a n n u . a . du rch die E l e k t r o l y t z u s a m m e n s e t z u n g beeinflui3t werden . Die Versuche ergaben, dab je nach Ka t hoden f I~che zwischen 2 u n d 0,01 p p m S 2g u t n a c h w e i s b a r stud. Das beobach t e t e Verha l t en der S i lbe rka thode in S2--hal t igen cyan id i schen S i lbere lek t ro ly ten n n d die V e r w e n d u n g zur Bes t i m m u n g yon ge r ingen S2--Mengen b e r u h e n auf der e x t r e m e n Schwer l6s l ichkei t des AgaS u n d der als Folge d a v o n au f t r e t en den R e a k t i o n

Hypertrophic non-obstructive cardiomyopathy caused by disorder of the myofiber texture.

Abstract: A case of hypertrophic non-obstructive cardiomyopathy caused by a disorder of the myofiber texture was observed in a 10 year old boy. The heart weighed 390 g and showed concentric hypertrophy of the left and right ventricles as well as of the ventricular septum. Additional findings consisted in an abnormal septum membranaceum and a accessory tricuspid valve leaflet. Severe cardic hypertrophy was associated with prominent interstitial and subendocardial fibrosis, and pronounced intimal fibrosis of the intramural arteries. Electron microscopy revealed various degrees and stages of hypertrophy of the myocardial cells combined with severe degenerative changes. Additional changes of the sinus node and conduction system were responsible for a tachycardia-bradycardia syndrome, complete left bundle branch block and final total AV-block.

The Maxwell field, its adjoint field and the ‘conjugate’field in anisotropic absorbing media

Abstract: In absorbing media, where Maxwell's equations are not seif-adjoint, the adjoint field is introduced via the differential operator adjoint to the Maxwell operator. The concomitant vector can be made equal to the time averaged Poynting vector at a boundary with a non-absorbing medium. In general, the adjoint field represents an electromagnetic field in a medium other than the absorbing medium under consideration. To draw conclusions about the latter, a [conjugate field] in this medium is defined, using a conjugating transformation of the Maxwell operator and field. Relations between the conjugate and adjoint fields are established, allowing one to gather physical information about the first absorbing medium from the adjoint field.

Synthesis of poly(A)-associated RNA in the prereplicative phase of isoproterenol-stimulated DNA synthesis.

Abstract: Rapidly labelled RNA containing poly(A) sequences has been isolated from polysomes of mouse parotid glands. Filtration on Millipore and binding to poly(U) immobilized on Sepharose-4B, together with significant RNase-resistance (11–16%) indicated that this polysomal fraction contains large tracts of polyadenylate sequences. A single injection of isoproterenol, a procedure that causes, after a lag period of 20 hrs, a marked stimulation of DNA synthesis and cell division in salivary glands of rodents, induces a biphasic increase in the incorporation of (3H)-adenosine into poly(A)-associated polysomal RNA. The incorporation of (3H)-adenosine is already increased within 1 hour after stimulation, decreases at 3hrs and increases again at 8 hrs, paralleling previously reported changes on chromatin template activity of mouse parotids. However, the percent poly(A) content, and the size of the poly(A)-associated RNA remain constant. Actinomycin D given 30 min prior to isoproterenol, inhibits isoproterenol-stimulated poly(A)-rich RNA synthesis. These results demonstrate that, as part of the early molecular events of its action, isoproterenol regulates transcription of adenylate-rich RNA in mouse parotid glands.

Tyrosinase activity in three types of the malignant melanoma: Superficial spreading melanoma, mentigo maligna melanoma and Nodular Melanoma

Abstract: Quantitative differences in the tyrosinase activity are found at the three types of malignant melanoma of Clark and Mihm by the combined 3,4-dihydroxyphenylalaninepremelanin-reaction. Only a very small activity is present in the junction nevus. In the superficial spreading melanoma the tyrosinase activity is clear, but limited. The lentigo maligna melanoma shows an increased pigmentation. The topmost activity after incubation however is present in the nodular melanoma.

The teratogenic effects in rabbits of doxycycline, dissolved in polyvinylpyrrolidone, injected into the yolk sac.

Abstract: A technique was developed for injecting agents into the yolk sac of rabbits to study their teratogenic effects. On the 9th day of gestation the rabbits were laparotomized during ether-oxygen narcosis. The test substance was injected into the yolk sacs in one horn of the uterus, and as control the corresponding solvent was injected into the other horn. On the 28th day of gestation the rabbits were killed, resorptions counted, and fetuses examined for malformations. Three series of studies were made: physiological saline; polyvinylpyrrolidone; and doxycycline dissolved in polyvinylpyrrolidone (DIP). The rate of resorptions and malformations significantly increased after injection of Vibravenos. As polyvinylpyrrolidone was not teratogenic it is concluded that the teratogenic effects of DIP were probably caused by doxycycline.

Endoscopic findings of maxillary sinus after middle face fractures

Abstract: Of 93 patients with fractures of the mid-face who appeared for postoperative check-up, 25 were selected by chance for sinuscopy of the maxillary sinus. Chronic inflammatory mucosal changes occurred in 35 per cent; other pathological sequelae included solitary polyps, mucocele, scarry synechia, and prolapse of orbital fat and osteoma. In spite of these findings, all patients were free of complaints. The primary surgical revision was therefore declined in favour of a waiting attitude. For the diagnostic clarification of late complications, sinuscopy with Hopkin's optics offers a simple and efficient procedure, which should be routinely utilised.

The group doppler effect

Abstract: The Doppler effect for the modulation of a wave signal is investigated. This group Doppler effect is considered for rays in inhomogeneous, dispersive, absorbing, anisotropic and time-varying media. In addition, the receiver or scatterer is allowed to move with respect to the medium. It is shown that the new effects depend on the group velocity and its direction relative to the normal.

Anchor effects and figural aftereffects: a comparative psychophysical investigation.

Abstract: Perceptual contrast effect was studied from two points of view, as a special anchor effect and as a special figural aftereffect. Two experiments were conducted to investigate the influence of stimulus onset asynchrony on contrast and assimilation effects, induced and measured by different psychophysical methods. Stimuli were circular beams of light projected on screens (Delboef type of illusion). When anchor and series stimuli were shown and the latter were judged by means of a rating scale, stimulus onset asychrony had no substantial influence on the contrast effect (Exp. I). When the constant method was applied, however, the asynchrony altered the shape of the contrast effect considerably (Exp. II).

Virilismus bei Nebennierenmarktumor mit ektopischem ACTH-Syndrom

Abstract: Es wird von einem 14jahrigen Madchen berichtet, bei dem mit 6 Jahren die Diagnose eines Adrenogenitalsyndroms gestellt wurde. Ursache des Virilismus/Hirsutismus war ein Nebennierenmarktumor mit ektopischem ACTH-Syndrom. Das radioimmunologisch im Tumor nachgewiesene ektopische ACTH fuhrte nicht zu einer maximalen Nebennierenrindenstimulation, so das die Mehrproduktion an ACTH durch den hypothalamischen-hypophysaren-adrenalen Regelkreis wahrend des Tages kompensiert werden konnte. Die erhohten Konzentrationen an Dehydroepiandrosteron, Ostron und Testosteron im Plasma und von 17-Ketosteroiden und freiem Cortisol im Urin waren adrenaler Herkunft. Nach Entfernung des Tumors trat spontan die Menarche ein, und die erhohten Plasmakonzentrationen normalisierten sich. Ein Adrenogenitalsyndrom konnte ausgeschlossen werden.

Construction of the upper lip, columella and orbicularis muscle in bilateral clefts

Abstract: Summary A concept for repair of double clefts is described. In the primary operations at the age of six months on the first side, and six weeks later on the other, it is important to supply the prolabial mucosa by muscular vermilion flaps from the lateral sides, crossing the midline. Thus a muscular ring in the vermilion is obtained. At the age of 3–4 years both remaining muscular halves of the lip are united. This is achieved together with lengthening of the columella, using broad prolabial forked flaps and reducing the broadened prolabium to a natural looking philtrum. Lips repaired this way are satisfying with regard to both appearance and function.