Texture density and normal development of visual depth avoidance

1970 ◽  
Vol 3 (2) ◽  
pp. 73-90 ◽  
Author(s):  
Bernard Z. Karmel ◽  
Patricia N. Miller ◽  
Lawrence Dettweiler ◽  
Gary Anderson
Keyword(s):  
Normal Development ◽  
Visual Depth ◽  
Texture Density

Depth Discrimination in Rats on Visual Cliffs

1964 ◽  
Vol 19 (2) ◽  
pp. 423-426 ◽  
Author(s):  
Doris C. Dehardt ◽  
David L. Whitney
Keyword(s):  
Visual Cliff ◽  
Visual Depth ◽  
Open Area ◽  
Deep Side ◽  
Open Model ◽  
Additional Information ◽  
Depth Discrimination ◽  
Texture Density ◽  
Shallow Side

On an open visual cliff rats significantly preferred the shallow side while on an otherwise comparable closed cliff they did not, suggesting either that depth discrimination is enhanced by the additional information provided by the deep side of the open model, or that animals merely avoided the large open area of the deep side. The latter suggests that side preferences in open model cliffs are not necessarily valid indicators of visual depth discriminability in rats. Texture density was not a sufficient cue for depth discriminability as indicated by the preference of Ss for 1-in. checks in both 3-in. vs 1-in. and 1-in. vs ¼-in. comparison tests.

Electron Microscopy of Silicon Deposits in Foliar Idioblasts of Magnolia Grandiflora

1976 ◽  
Vol 34 ◽  
pp. 374-375
Author(s):  
Michael T. Postek
Keyword(s):  
Electron Microscopy ◽  
Water Loss ◽  
Normal Development ◽  
Magnolia Grandiflora ◽  
Plant Body ◽  
Normal Metabolism ◽  
Hydrated Oxide

Silicon occurs naturally in plants in the form of its hydrated oxide (SiO2.nH2O) commonly called silica. Silica has been shown to be a necessary element in the normal development of many plants, playing an array of roles including strengthening, protection, and reduction of water loss. Deposition of silica in various portions of the plant body, especially the leaves, may also be viewed as a way for the plant to dispose of any excess silica taken up beyond that necessary for normal metabolism.Studies of this “opaline” silica have thus far been limited to species of the Cyperaceae and Gramineae known to possess significant quantities of silica. Within the Magnoliaceae, certain “glistening” idioblast cells at the foliar veinlet termini and vein sheaths of Magnolia grandiflora (1) have been suspected to be siliceous in nature.

Localization of Intracisternal a Particle Antigens in Neoplastic Cells and Preimplantation Mouse Embryos

1980 ◽  
Vol 38 ◽  
pp. 696-697
Author(s):  
Thomas T.F. Huang ◽  
Patricia G. Calarco
Keyword(s):  
Endoplasmic Reticulum ◽  
Normal Development ◽  
Mouse Embryos ◽  
Neoplastic Cells ◽  
Large Numbers ◽  
Preimplantation Mouse Embryos ◽  
Preimplantation Mouse ◽  
Intracisternal A Particle ◽  
Normal Feature

The stage specific appearance of a retravirus, termed the Intracisternal A particle (IAP) is a normal feature of early preimplantation development. To date, all feral and laboratory strains of Mus musculus and even Asian species such as Mus cervicolor and Mus pahari express the particles during the 2-8 cell stages. IAP form by budding into the endoplasmic reticulum and appear singly or as groups of donut-shaped particles within the cisternae (fig. 1). IAP are also produced in large numbers in several neoplastic cells such as certain plasmacytomas and rhabdomyosarcomas. The role of IAP, either in normal development or in neoplastic behavior, is unknown.

Lexical Comprehension in Young Children With Developmental Delays

1994 ◽  
Vol 3 (1) ◽  
pp. 79-88 ◽  
Author(s):  
Theresa A. Kouri
Keyword(s):  
Young Children ◽  
Developmental Delays ◽  
Normal Development ◽  
Clinical Applications ◽  
Group Status ◽  
Novel Object ◽  
Related Information ◽  
Comprehension Skills ◽  
Lexical Items ◽  
Lexical Concepts

Lexical comprehension skills were examined in 20 young children (aged 28–45 months) with developmental delays (DD) and 20 children (aged 19–34 months) with normal development (ND). Each was assigned to either a story-like script condition or a simple ostensive labeling condition in which the names of three novel object and action items were presented over two experimental sessions. During the experimental sessions, receptive knowledge of the lexical items was assessed through a series of target and generalization probes. Results indicated that all children, irrespective of group status, acquired more lexical concepts in the ostensive labeling condition than in the story narrative condition. Overall, both groups acquired more object than action words, although subjects with ND comprehended more action words than subjects with DD. More target than generalization items were also comprehended by both groups. It is concluded that young children’s comprehension of new lexical concepts is facilitated more by a context in which simple ostensive labels accompany the presentation of specific objects and actions than one in which objects and actions are surrounded by thematic and event-related information. Various clinical applications focusing on the lexical training of young children with DD are discussed.

The Animal Models for Hemorrhage and Thrombosis in the Neonate

1987 ◽  
Vol 57 (01) ◽  
pp. 118-122 ◽  
Author(s):  
C Thomas Kisker
Keyword(s):  
Animal Models ◽  
Normal Development ◽  
Relevant Information ◽  
Relevant Model ◽  
Current Information ◽  
Single Animal ◽  
Hemostatic Disorders ◽  
Thrombotic Diseases

SummaryAnimal models have added significantly to our understanding of adult hemorrhagic and thrombotic diseases. Few models, however, have been developed for studies of the hemostatic disorders in the fetus and newborn. This report reviews the current information on animal models of fetal and neonatal hemostasis. The requirements of a relevant model are addressed and previous studies using fetal and neonatal animal models are reviewed. A recommendation of a single animal for all studies of fetal and neonatal hemostasis is not possible. However, the lamb has been the most frequently studied and appears to provide relevant information regarding normal development and the factors which may adversely influence hemostasis in the fetus and newborn.

Pathological features of the sequence in pregnant women with delayed fetal growth

2019 ◽  
pp. 50-54
Author(s):  
V.O. Golyanovskiy ◽  
◽  
Ye.O. Didyk ◽  
Keyword(s):  
Pregnant Women ◽  
Intrauterine Growth Restriction ◽  
Normal Development ◽  
Intrauterine Infection ◽  
Normal Pregnancy ◽  
Growth Restriction ◽  
Control Group ◽  
Intrauterine Growth ◽  
Increased Risk ◽  
Infection And Inflammation

Pregnant women with intrauterine growth restriction (IUGR) have an increased risk of adverse perinatal and long-term complications compared with the birth of children with normal body weight. Thus, IUGR is one of the main challenges for the global health system, especially in poor and developing countries. Morpho-functional studies of the placentas help in determining the causes of IUGR, and therefore, timely prevent complications in pregnant women with IUGR. The objective: The purpose of this study is to investigate various morphometric and pathomorphological changes in the placenta, including inflammatory, in cases of IUGR, and to establish a correlation of these results with the etiology and complications for the fetus. Materials and methods. In the current study, 54 placentas of the fetuses with IUGR (the main group) were compared with 50 placentas of the fetuses with normal development (control group). The criteria for the inclusion of IUGR were gestational age more than 30 weeks and all fetuses with a weight less than 10th percentile for this period of pregnancy. The placenta material was studied pathomorphologically with laboratory screening for infection and inflammation. Similarly, the results were determined for placentas of the fetuses with normal development compared to placentas with IUGR. Results. The placenta study showed the presence of calcification in the case of IUGR, as well as in the case of prolonged pregnancy. However, calcification of the placenta in the case of IUGR was more progressive compared with placenta in the normal pregnancy. In addition, the presence of intrauterine infection and inflammation was observed, which could also lead to an adverse outcome for the further progression of pregnancy with IUGR. Conclusion. A comparative macro- and microscopic pathomorphological study of the placentas in the two groups has shown a significant increase in the pathological changes in all the anatomical structures of the fetuses with IUGR. Key words: Intrauterine growth restriction (IUGR), fetal weight, pathomorphological changes of the placenta.

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