Types Of Retraction Research Articles

RETRACTING 1-SIMPLICIAL CHAOTIC GRAPHS WITH DENSITY VARIATION

In this paper we will discuss retraction transformation on chaotic graphs for different cases of density variation, Two types of retraction will be discussed, geometric retraction and chaotic edges retraction, We shall study and discuss the effects of retraction on the shape and density degree of chaotic graphs shown on figures, the adjacent and incidence matrices with be presented. The density character may present many applications in life such as degree of green color in plants, net perturbation resonance, signals in the nerve system and so many, we focus our study on plants, how retraction effects of the degree of green color of plants leaves and shape of the leave its self. The variation of the density character shows the variation of the degree of green color of plant (i.e. Chlorophyll), so we divided in three cases, the first case when the leave of plant is unit and constant everywhere, or varied from level to level or varied even in the same level line of a plant leave, each case will be discussed for two types of retraction and deduce results for both types.

Types of Foreskin Retraction in Children in Hospital Belen of Trujillo, Perú


 
 
 Introducción: El prepucio es la parte de la piel que recubre el glande. Al nacer, el recién nacido tiene un prepucio estrecho, adherente y largo, con punta angosta que sobrepasa el extremo distal del glande.
 Objetivos: Determinar los tipos de retracción del prepucio según la edad en niños menores de 15 años.
 Materiales y métodos: Se realizó el examen clínico a 360 niños divididos en 9 grupos de 40 cada uno. Fueron atendidos en el Departamento de Pediatría del Hospital Belén de Trujillo. Se evaluó el grado de retracción del prepucio aplicando la clasificación de Kayaba, según grupo etario.
 Resultados: Muestran que los tipos de retracción del prepucio I y II son más frecuentes en recién nacidos (45% y 52.5%) y niños menores de 6 meses (35% y 32.5%), el tipo V no se encuentra en menores de 6 meses (0% en ambos grupos). En los niños de 11 a 15 años predomina el tipo V (75%) y no se encuentran los tipos I y II (0%).
 Conclusiones: A mayor edad aumenta la retracción del prepucio. Los tipos de retracción del prepucio I y II predominan en los recién nacidos y niños menores de 1 año de edad y los tipos IV y V predominan en los niños entre 11 y 15 años.
 
 

Fuzzy Retraction of Fuzzy Space Time

Our aim in the present article is to introduce and study a new type of metric, namely fuzzy space time metric. The geodesics of fuzzy space time metric will be obtained from the view point of Lagrangian equations. Types of the fuzzy retraction of fuzzy space time metric are presented. Types of the fuzzy folding of fuzzy space time metric are defined and discussed. The deformation retraction is also discussed. Some applications concerning these relations are presented. Keywords: Fuzzy Space Time Metric, Fuzzy Retraction, Fuzzy Deformation Retraction, Fuzzy Geodesics, Fuzzy Folding. 2000 Mathematics Subject Classification: 53A35, 51H05, 58C05.

Retractions of One Dimensional Manifold

Our aim in the present article is to introduce and study types of retraction of one dimensional manifold. New types of geodesics in one dimensional manifold are presented. The deformation retracts of one dimensional manifold into itself and onto geodesics is deduced. Also, the isometric and topological folding in each case and the relation between the deformations retracts after and before folding has been obtained. New types of conditional folding are described.

The Intercartilaginous Graft for Actual and Potential Alar Retraction

Alar retraction deformities occasionally require significant soft-tissue release and relatively large cartilage grafts. In addition, correction of the short nose by only lengthening the septum can result in potential postoperative alar retraction. Consequently, both types of cases, true and potential alar retraction (in short noses), would benefit from a technique that lengthens the sidewall of the nose. The intercartilaginous graft technique is a modification of the lateral crural strut graft technique. An intercartilaginous graft is inserted between the upper lateral cartilage and what remains of the lateral crus (lateral crus element). The technique emphasizes maximum soft-tissue release to insert a cartilaginous graft that spans the gap between the upper lateral cartilage and the lateral crus element. The graft is inserted under slight tension to maintain maximum lengthening of the sidewall of the nose. Thirteen patients had intercartilaginous grafts placed. Seven patients had actual alar retraction and six patients had short noses with potential alar retraction. There was no postoperative alar retraction in 10 patients. Two patients with actual alar retraction were not completely corrected, and one required surgical revision. One patient with a short nose exhibited postoperative alar retraction, but it was not significant enough to warrant reoperation. The intercartilaginous graft technique, a modification of the lateral crural strut graft technique, corrects moderate to severe alar retraction and prevents alar retraction after lengthening of very short noses. Its success depends on substantial soft-tissue release and insertion of a maximal sized graft between the upper lateral cartilage and the lateral crus element under slight tension.

Retraction Phenomena of Surfactant Solution Drops upon Impact on a Solid Substrate of Low Surface Energy

The impact of surfactant solutions drop on a low-surface-energy solid substrate is investigated using a high-speed photographic technique (one picture every 100 μs) which allows simultaneous top and side views. The influence of physicochemical properties is analyzed by varying the adsorption kinetics of the surfactants and the initial diameter and velocity of the drop before impact. Generally, the drop spreads and retracts under the action of inertia and capillarity, respectively. During spreading, the drop shape changes from a “truncated sphere” to a “flat pancake” and the drop surface is increased such that it is no longer at thermodynamic equilibrium. The relevant surface property is therefore the dynamic surface tension which is evaluated at the maximum diameter γdmax, using the maximum bubble pressure apparatus. The dynamic surface tension has a critical influence on the drop behavior at the maximum diameter dmax and during the subsequent retraction. A simple relation combining γdmax and the dynamic contact angle at dmax is derived to predict dmax. The results of this prediction agree well with the experimental measurements. Since γdmax is large compared with the critical surface tension of the solid surface, a retraction of the drop is induced. The physical origin of this retraction is the apparent dynamic spreading coefficient Smax whose absolute value is correlated with the extent of the retraction. Two types of retraction are observed: a fast, destabilizing one which is described as an inertial peripheral dewetting and a slow, stabilizing one which relaxes exponentially. An empirical criterion is given on the basis of the difference between the thickness of the flattened drop at the maximum diameter and the critical thickness of metastability of a film in partial wetting conditions. It is demonstrated experimentally that this retraction proceeds on a clean solid surface and that the dewetted area is not modified by any surfactant adsorption which could have occurred during the contact time.

Injury Stimulates Outgrowth and Motility of Oligodendrocytes Grownin Vitro

Oligodendrocytes which form myelin within the CNS develop from small, highly motile cells that are largely bipolar into mature cells which extend many processes and which produce myelin membranes around multiple axons. The production of myelin sheaths is thought to anchor mature oligodendrocytes (OLs), limiting their motility. When the brain sustains an injury, OLs do not make a significant effort to remyelinate, a fact attributed to both their lack of proliferation and their inability to migrate or extend processes into areas of injury. To test the motility and growth potential of mature OLs, we have designed anin vitrosystem in which individual cells can undergo long-term observation. Additionally, cells can be mechanically injured by transection of processes using a low-power laser beam. Both control and injured OLs undergo several types of structural change, including extension and retraction of processes and membranes, as well as changes in process caliber. Some OLs exhibit a high degree of motility, moving several hundred micrometers within days. Rather than interfering with the cells’ ability to undergo structural change, injury actually stimulated outgrowth of new processes and motility. Neither injury nor addition of basic fibroblast growth factor (bFGF) increased the rate of OL division. However, bFGF paradoxically caused an increase in uptake of the DNA synthesis marker bromodeoxyuridine and had negative effects on OL survival. The unexpected findings that OLs with a mature phenotype are motile and undergo constant structural modificationin vitroand that injury induces certain behaviors suggest that myelin-forming OLs in the brain may be capable of a high degree of plasticity under certain conditions.

Correlation between retractions of the pars flaccida and the pars tensa.

Retractions of the pars flaccida (PF) and the pars tensa (PT) were assessed in 250 atelectatic ears in an attempt to find out the way in which the differences in mechanical properties of the two parts of the tympanic membrane are reflected clinically. Retraction of PF was found in 217 ears (86.8 per cent) and retraction of PF in 150 (60 per cent). The concomitant presence of both types of retraction was observed in 117 ears (46.8 per cent) while 133 (53.2 per cent) had only one type, 100 of them (75.1 per cent) PF retraction and 33 (24.9 per cent) PT retraction. When only one type of retraction was present, the empirical probability of having a PF retraction was 75.1 per cent, while the probability of having a PT retraction was only 24.9 per cent. Clinically, the more frequent occurrence of PF retraction in the absence of PT retraction than vice versa reflects the greater collapsibility of the PF. When both types of retractions were present, we found a positive correlation between their severity.

Attic retractions following secretory otitis.

At re-examination of 527 ears with secretory otitis 3 to 8 years after tubulation otomicroscopy and tympanometry revealed different types of retraction of Shrapnell's membrane in 34%, of these 4.2% had pronounced retraction with resorption of the osseous annulus and 0.2% had atticus cholesteatoma. There was a close correlation between the frequency and severity of retraction on the one hand and the age of the patient at reexamination, the tympanometric conditions, and the pathology of pars tensa on the other. The continued progression is further promoted by a lack of natural cleansing of the retraction. As the frequency of secretory otitis is very high in children the 4.2% of pronounced retractions constitute a sufficient quantitative basis for a direct progression to atticus cholesteatoma.

The Use of Thymoxamine in Eyelid Retraction

We observed substantial narrowing in 75% of fissures in patients with various types of lid retraction after topical application of aqueous 0.5% thymoxamine (moxisylyte). Even contralateral normal-appearing fissures in thyroid patients responded in this manner. The nonresponders in the lid retraction group included a patient with an orbital pseudotumor and patients with long-standing and stable euthyroid eye disease. No normal subjects' fissures responded greatly to thymoxamine. A substantial reduction in palpebral fissures was seen in all patients with thick extraocular muscles and in 14 of 18 (78%) of all fissures of thyroid patients; the average response was 2.3 mm. This effect may last for five hours after thymoxamine administration. Thymoxamine may be of use as a diagnostic test for thyroid eye disease, and if it can be modified to cause less ocular irritation, it may be beneficial in the medical treatment of eyelid retraction.