CRITICAL PERIODS OF ADAPTATION TO SMOKE AND SOLAR ACTIVITY IN HUMAN ONTOGENESIS: A REVIEW

The aim: To investigate morphology and developmental features of anatomical structures in the infrahyoid triangles of human neck during prefetal and fetal periods of human ontogenesis. Materials and methods: We have studied 30 specimens of human prefetuses from 7th till 12th week (16,0-82,0 mm of parieto-coccygeal length (PCL)) and 30 human fetuses aged from 4th till 10th month (84,0-360,0 mm PCL) of intrauterine development by the means of macro-, microscopy, morphometry, three-dimensional remodeling and statistical analyses. Results: We can observe anterior triangle in human fetuses after the time when common precursor muscular mass splits into two: the anterior and posterior portions which will give rise to the sternocleidomastoid and trapezoid muscles accordingly. The area index of the central triangle in human fetuses 4th – 10th month of intrauterine development shows the increasing tendency with the highest rates at 8th–10th months period – 1100-1200 mm2. The angulated course of omohyoid muscle is visible at late prefetal and early fetal periods (3-4th month; 80,0-130,0 PCL) as well as the presence of intermediate tendon. Peaks of the area of sternocleidomastoid region area evaluation was observed in 190,0-210,0 mm PCL and 260,0-270,0 mm PCL human fetuses; 6th and 7,5th months accordingly. Conclusions: The critical periods for the AT and SCM regions should be considered 6th and 8th months of the IUD. Prefetal period shows the presence of AT and border structure for the IH neck – precursor of HB. Fetal period of IUD (4th – 10th months of IUD) should be considered as such that represents an adult-alike morphology of IH neck: presence of IH triangles with fully developed vascular, muscular and fascial content.

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MODERN INFORMATION ON THE PANCREATIC STRUCTURES FORMATION IN THE EARLY STAGES OF HUMAN ONTOGENESIS

Clinical anatomy and operative surgery ◽

10.24061/1727-0847.19.1.2020.21 ◽

2020 ◽

Vol 19 (1) ◽

pp. 117-123

Author(s):

O. Slobodіan ◽

N. Hrymailo ◽

A. Zavolovych ◽

M. Vatcyk

Keyword(s):

Perinatal Period ◽

Practical Significance ◽

Critical Periods ◽

New Approach ◽

Developmental Abnormalities ◽

Fetal Period ◽

Early Stages ◽

Human Ontogenesis ◽

Modern Information ◽

Anatomical Research

The expansion of human anatomical research at all stages of embryonic development is extremely necessary, as many children and adults diseases are etiologically associated with the fetal period. The study of the laws of bookmarking, development and formation of topographic and anatomical relationships of the pancreas with adjacent organs in the early stages of human development is of great interest and has not only theoretical but also practical significance. Analyzing the literature on the morphology of the pancreas at different stages of the perinatal period of ontogenesis, as well as information about developmental abnormalities, despite the presence of a relatively large number of works, the authors' opinions differ and need further consideration for clarification. Stages and critical periods of formation of the pancreas should be considered as a reflection of a new approach to understanding the ontogenetic features of development.

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Peculiarities of morphogenesis of orbit and organ of vision structures in human fetuses

Bukovinian Medical Herald ◽

10.24061/2413-0737.xxv.1.97.2021.14 ◽

2021 ◽

Vol 25 (1(97)) ◽

pp. 95-102

Author(s):

A. Tsyhykalo ◽

N. Kozariichuk ◽

K. Yakovets ◽

H. Kulynych

Keyword(s):

Growth Rates ◽

Three Dimensional ◽

Lateral Wall ◽

Human Fetuses ◽

Critical Periods ◽

Facial Skeleton ◽

Intrauterine Development ◽

Fetal Period ◽

Age Related ◽

Human Ontogenesis

The aim of this work is to elucidate the features of morphogenesis, syntopic and morphometric changes in the structures of the orbit, neurovascular and muscular structures of the organ of vision in the fetal period of human ontogenesis.Material and methods. By means of complex of methods of morphological research (anthropometry, morphometry, microscopy, preparation, three-dimensional computer reconstruction and statistical analysis), 30 specimens of human fetuses of both sexes aged from 4 to 10 months of intrauterine development (IUD) (160.0-460.0 mm parietal-coccygeal length (PCL)) were studied. Computer tomography was used to study 17 human fetuses aged from 4 to 9 months of IUD (180.0-440.0 mm PCL).Results. At the end of the 5th month of IUD, an orbital index is 75%, which is noted in the transformation of the shape of orbit from flattened to rounded due to an increase in its vertical size relative to the horizontal one. We associate this transformation of the orbit with syntopic influence of adjacent regions: the growth of the lateral wall of the nasal cavity, development of the paranasal sinuses, and facial skeleton. At the end of the 5th week of intrauterine development, external eyeball muscles are finally differentiated from the common muscle rudiment. The analysis of changes in morphometric parameters of muscles of the eyeball made it possible to derive mathematical functions, that describe normal dynamics of growth of their length, as well as to reveal critical periods of their development in terms of the rate of changes in their thickness and width.Conclusions1. The development of the organ of vision in the fetal period of human ontogenesis is a complex process due to the coordinated interaction between morphological and morphometric changes in the orbit, eyeball and its muscles, nerves and vessels.2. Critical periods of development of the orbit and its structures is the 6th month of intrauterine development, during which there is an uneven growth rate of the size of the muscles of the eyeball, as well as the size of the orbit.3. At the 6th month of intrauterine development, uneven growth rates of the horizontal size of the orbit relative to the vertical one are observed, as a result of which its shape begins to return to the mesoconchal type characteristic of such prefetuses. Such age-related transformations of shape and size of the orbit are due to the growth of the eyeball, skull and face, which generally determines the shape of the orbit.4. Starting from the 8th month of fetal period of development, structure and topography of the structures of the orbit acquire signs of a definitive condition, the shape of the orbit is finally established, and uniform growth rates of all structures of the organ of vision are observed, except for the growth of the circumference of the orbit at the end of prenatal period of human ontogenesis.

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Influence of Magnetic Fields on Solar Hydrodynamics: Experimental Results

International Astronomical Union Colloquium ◽

10.1017/s025292110005329x ◽

1977 ◽

Vol 36 ◽

pp. 143-180 ◽

Cited By ~ 10

Author(s):

J.O. Stenflo

Keyword(s):

Solar Activity ◽

Energy Balance ◽

Magnetic Fields ◽

Solar Atmosphere ◽

General Problem ◽

Solar Rotation ◽

Active Regions ◽

Physical Conditions ◽

Dynamic Phenomena

It is well-known that solar activity is basically caused by the Interaction of magnetic fields with convection and solar rotation, resulting in a great variety of dynamic phenomena, like flares, surges, sunspots, prominences, etc. Many conferences have been devoted to solar activity, including the role of magnetic fields. Similar attention has not been paid to the role of magnetic fields for the overall dynamics and energy balance of the solar atmosphere, related to the general problem of chromospheric and coronal heating. To penetrate this problem we have to focus our attention more on the physical conditions in the ‘quiet’ regions than on the conspicuous phenomena in active regions.

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Prominences and Solar Activity

International Astronomical Union Colloquium ◽

10.1017/s0252921100065817 ◽

1979 ◽

Vol 44 ◽

pp. 357-372

Author(s):

Z. Švestka

Keyword(s):

Solar Activity ◽

Solar Cycle ◽

List Type ◽

Type Number ◽

Flare Loops ◽

Filament Activation

The following subjects were discussed:(1)Filament activation(2)Post-flare loops.(3)Surges and sprays.(4)Coronal transients.(5)Disk vs. limb observations.(6)Solar cycle variations of prominence occurrence.(7)Active prominences patrol service.Of all these items, (1) and (2) were discussed in most detail and we also pay most attention to them in this report. Items (3) and (4) did not bring anything new when compared with the earlier invited presentations given by RUST and ZIRIN and therefore, we omit them.

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