Number Of Globules Research Articles

Introduction

The electron microscopical picture of the adrenal cortex in intact, adult, male, white mice is characterized by the following main features and their zonal variations. The adrenal gland is invested by a capsule composed of fibrils arranged in bundles and of basement-membrane-like capsular membranes interwoven between 3 to 4 layers of radially flattened cells. The adrenocortical capillaries are provided with an endothelial wall only 400thick along most of the luminal perimeter, and in this wall there are cytoplasmic discontinuities with a width of 400which are bridged by a simple membrane 50thick. Vesicles having a diameter of 500are the most characteristic feature in the cytoplasm of the endothelial cells. Throughout the adrenal cortex a space separates every capillary endothelium from neighbouring epithelial structures. This space is continuous with the intercommunicating system of extracellular spaces around the epithelial columns. Hence the entire adrenal cortex is pervaded by an intricate network of spaces which actually are branches of a single integral space. This is here as a whole called the periendothelial space. The periendothelial space generally contains two basement membranes—one epithelial and one endothelial or two epithelial. Pericapillary cells are found in the periendothelial space between basement membranes. Their nuclei and perinuclear cytoplasm is encountered near a capillary and the rest of the cytoplasm forms long processes extending into the periendothelial space, the cell as a whole apparently being especially adapted to conform with the configuration of this space. In addition the periendothelial space contains up to 0.4 μ long and 650thick microvilli projecting from the epithelial cells. Here four adrenocortical zones have been distinguished which, proceeding from the capsule to the medulla, are called the glomerular zone, the outer fascicular zone, the inner fascicular zone and the reticular zone. Mitochondria are plentiful in the epithelial cells of all cortical zones but their shape, outer membrane and inner structure exhibit zonal differences. The mitochondria differ significantly in breadth from one zone to another. The mitochondrial outer membrane, for the most part three-layered, may be simple along occasional portions of the periphery. Whilst the glomerular zone exclusively has mitochondria of tubulosaccular type, the mitochondrial inner structure in the deeper zones may be either tubulosaccular or membranous; and if membranous, predominantly rectimembranous in the outer fascicular zone and mainly cyclomembranous in the inner fascicular zone. Lipid droplets occur in the epithelial cells of all cortical zones. They are of round or oval shape in the two peripheral zones and irregular in the two deeper zones. Lipid droplets are usually intensely osmiophilic throughout in the glomerular, inner fascicular and reticular zones, whereas in the outer fascicular zone the osmiophilic matter in the lipid droplets tends to be concentrated into lumps or grains in the central portions of the droplet and into a marginal zone. Some droplets are entirely lacking in osmiophilic matter so they are instead called lipid vacuoles. Globules, round formations 0.33 μ in diameter outlined by a smooth and even three-layered surface membrane, are encountered in all cortical zones. Globules have a heterogeneous inner structure composed partly of regions with dense granules, partly of patches of homogeneously dark matter. The number of globules in a cell increases with increasing distance from the adrenal periphery. Cytoplasmic vacuoles and cytoplasmic vesicles occur in all cortical zones but are most numerous in epithelial cells from the two deeper zones. The cytoplasm of epithelial cells contains dense minute granules with a diameter of 150 . They are most numerous in glomerular epithelial cells and become less frequent with increasing depth into the cortex. In the reticular zone pigment bodies are seen which often exhibit a structure composed of arcuated osmiophilic stripes around light areas with dense granules along the boundary between the two former components. After parenteral administration of 1 mg of hydrocortisone acetate daily for 7 days, the adrenal cortex in similar mice exhibited ultrastructural changes varying in degree from animal to animal and from epithelial cell to epithelial cell but tending to be most pronounced in the deeper portions of the cortex. The main characteristic of the altered epithelial cells was the appearance of a great number of large lipid vacuoles among which a few mitochondria scarcely could be distinguished. Moreover, the number of pigment bodies was greater and pigment-like masses had appeared, particularly in the cells in the deep cortical zones. In a fluorescence microscopic control study it was verified that yellow fluorescing granules occur in the reticular zone of the cortex in intact mice and also that the number of such yellow fluorescing granules was significantly higher in mice which had received hydrocortisone parenterally as described above.

Ultrastructure of the mouse adrenal cortex: An electron microscopical study in intact and hydrocortisone-treated male adults

The electron microscopical picture of the adrenal cortex in intact, adult, male, white mice is characterized by the following main features and their zonal variations. The adrenal gland is invested by a capsule composed of fibrils arranged in bundles and of basement-membrane-like capsular membranes interwoven between 3 to 4 layers of radially flattened cells. The adrenocortical capillaries are provided with an endothelial wall only 400thick along most of the luminal perimeter, and in this wall there are cytoplasmic discontinuities with a width of 400which are bridged by a simple membrane 50thick. Vesicles having a diameter of 500are the most characteristic feature in the cytoplasm of the endothelial cells. Throughout the adrenal cortex a space separates every capillary endothelium from neighbouring epithelial structures. This space is continuous with the intercommunicating system of extracellular spaces around the epithelial columns. Hence the entire adrenal cortex is pervaded by an intricate network of spaces which actually are branches of a single integral space. This is here as a whole called the periendothelial space. The periendothelial space generally contains two basement membranes—one epithelial and one endothelial or two epithelial. Pericapillary cells are found in the periendothelial space between basement membranes. Their nuclei and perinuclear cytoplasm is encountered near a capillary and the rest of the cytoplasm forms long processes extending into the periendothelial space, the cell as a whole apparently being especially adapted to conform with the configuration of this space. In addition the periendothelial space contains up to 0.4 μ long and 650thick microvilli projecting from the epithelial cells. Here four adrenocortical zones have been distinguished which, proceeding from the capsule to the medulla, are called the glomerular zone, the outer fascicular zone, the inner fascicular zone and the reticular zone. Mitochondria are plentiful in the epithelial cells of all cortical zones but their shape, outer membrane and inner structure exhibit zonal differences. The mitochondria differ significantly in breadth from one zone to another. The mitochondrial outer membrane, for the most part three-layered, may be simple along occasional portions of the periphery. Whilst the glomerular zone exclusively has mitochondria of tubulosaccular type, the mitochondrial inner structure in the deeper zones may be either tubulosaccular or membranous; and if membranous, predominantly rectimembranous in the outer fascicular zone and mainly cyclomembranous in the inner fascicular zone. Lipid droplets occur in the epithelial cells of all cortical zones. They are of round or oval shape in the two peripheral zones and irregular in the two deeper zones. Lipid droplets are usually intensely osmiophilic throughout in the glomerular, inner fascicular and reticular zones, whereas in the outer fascicular zone the osmiophilic matter in the lipid droplets tends to be concentrated into lumps or grains in the central portions of the droplet and into a marginal zone. Some droplets are entirely lacking in osmiophilic matter so they are instead called lipid vacuoles. Globules, round formations 0.33 μ in diameter outlined by a smooth and even three-layered surface membrane, are encountered in all cortical zones. Globules have a heterogeneous inner structure composed partly of regions with dense granules, partly of patches of homogeneously dark matter. The number of globules in a cell increases with increasing distance from the adrenal periphery. Cytoplasmic vacuoles and cytoplasmic vesicles occur in all cortical zones but are most numerous in epithelial cells from the two deeper zones. The cytoplasm of epithelial cells contains dense minute granules with a diameter of 150 . They are most numerous in glomerular epithelial cells and become less frequent with increasing depth into the cortex. In the reticular zone pigment bodies are seen which often exhibit a structure composed of arcuated osmiophilic stripes around light areas with dense granules along the boundary between the two former components. After parenteral administration of 1 mg of hydrocortisone acetate daily for 7 days, the adrenal cortex in similar mice exhibited ultrastructural changes varying in degree from animal to animal and from epithelial cell to epithelial cell but tending to be most pronounced in the deeper portions of the cortex. The main characteristic of the altered epithelial cells was the appearance of a great number of large lipid vacuoles among which a few mitochondria scarcely could be distinguished. Moreover, the number of pigment bodies was greater and pigment-like masses had appeared, particularly in the cells in the deep cortical zones. In a fluorescence microscopic control study it was verified that yellow fluorescing granules occur in the reticular zone of the cortex in intact mice and also that the number of such yellow fluorescing granules was significantly higher in mice which had received hydrocortisone parenterally as described above.

Statistical Study of Globules Projected on Stellar Clouds

The discovery of globules by Bok and Reilly leads to various speculation concerning their cosmogonical meaning as protostellar bodies in our galaxy.It is well known that the most favorable conditions for the discovery and study of globules are reached when they are connected with diffuse galactic nebulae (Dufay). Observations show that in this case globules possess various and generally irregular shapes. It is quite probable that these globules are connected with large dark clouds, genetically linked with bright nebulae. The number of globules in a nebula depends essentially on the peculiarity of its structure. Nevertheless the total area of the sky covered by the nebulae is relatively small and their physical conditions depending on nearby hot stars are peculiar. Consequently it is hardly possible to suppose that the properties of globules present in nebulae are the same as in the other regions of the galaxy. It is important to collect more data concerning the spatial distribution of globules, their density, sizes etc. The stellar clouds of the Milky Way give some possibility for further study in this respect. In the case of a sufficiently dense stellar field the projecting globules can be discovered as some fluctuations in the stellar population as observed on the photograph.

671. The association between the fat percentage of cows' milk and the size and number of the fat globules

Milk samples were collected, between 17 April and 30 May 1956, from fifty-six Ayrshire and forty Friesian cows, which had been calved for between 45 and 165 days, when they were running out at grass day and night. The results showed that differences in the fat percentages of their milk were accompanied by corresponding variations in the average diameter of the globules in both breeds and in the numbers of globules per cu.mm. in the Friesian cows. These changes were not significant for either variant because there were some individuals in which changes in fat percentage appeared to be accounted for by either an increase in fat globule diameter or an increase in the number per cu.mm. with correspondingly low figures for the other variant.

A search for globules in the Palomar Sky Atlas.

view Abstract Citations (2) References (1) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A search for globules in the Palomar Sky Atlas. Fleischer, Robert ; Conti, Peter S. Abstract A search has been made on prints of the Palomar Sky Atlas for globules, or small roundish dark nebulae. On the blue exposures 0-175 with galactic longitude 3330, latitude - 10, and 0-159 with longitude 3370, latitude +~0, a first survey has resulted in not less than 10,000 and 7000 globules, respectively. The diameter of a typical object is I millimeter on the prints, or about I minute of arc. The reality of these suspected globules is plausible in view of the a priori probability of I in 4000 of finding a one-millimeter circle with zero stars on a similar plate of randomly distributed stars, and also in view of the improbability of the star formations, rings, loops, and concave wedges, which mark their boundaries. Attempts to show that random distributions of dots would show "globules" failed due to the difficulty of producing true random distributions. A count of stars in 340 one-millimeter squares in a typical region of print 0-175 showed that the stars were not distributed at random in the squares. The assumption of a random distribution of stars overlain with the 21 globules marked in this region led to a predicted distribution of star numbers with a ~` probability of 5 per cent that it represents the observed star numbers. This is considered satisfactory evidence that the large number of globules is probably real. Our typical globules are about 3 times the diameter of those marked by Bok and Reilly (1947). They supposed their globules to be at an average maximum distance of 1260 parsecs. If we assume ours to be closer in proportion to the apparent diameters, or at 420 parsecs, we find a space density of not less than 0.03 globules per cubic parsec, which may be compared with an average space density in the vicinity of the sun of 0.1 stars per cubic parsec. As this is a preliminary progress report, no more extensive publication is intended in the immediate future. A mimeographed report is available giving more details on the above points and some other provisional results of the search. Acknowledgment is made with thanks to the Research Grants Committee of Rensselaer Polytechnic Institute for a grant to the senior author for partial support of the purchase of the Atlas. Bok, B. J. and Reilly, E. F. 1947, Ap. J. 105, 255. Observatory, Rensselaer Polytechnic Institute, Troy, N. V. Publication: The Astronomical Journal Pub Date: February 1956 DOI: 10.1086/107269 Bibcode: 1956AJ.....61....4F full text sources ADS |

A Mechanism for the Fuse Pre-Arcing Period [includes discussion

The equation of heat conduction for a cylindrical fuse wire is considered, and approximate solutions are given for the case of a simple cartridge fuse to show the variation of the temperature distribution along the element for different fusing currents and different cartridge dimensions. The melting period is examined analytically, and it is shown how, above a certain current density, the element begins melting from the surface inwards instead of from the inside outwards. This mechanism depends on a variation of the melting temperature over the cross section caused by the pinch pressure. If the inside melts first, breakup is due to the internal pressure produced and is irregular; if the surface melts first, the breakup depends on the parameters of the molten metal. A general theory, from Lord Rayleigh, for the breakup of a liquid cylinder under surface forces is applied to the latter case, and criteria of size are established for the parameters so that the element will break up in a regular fashion to form a definite number of globules, and so that the element will break up irregularly at infrequent intervals.

470. The distribution of fat-globule size in sow's milk: I. The effect of sampling at intervals throughout milking

An improved method for the determination of fat-globule size distribution has been worked out and applied to samples of sow's milk drawn sequentially. The distribution patterns for the globule sizes of sow's milk have been determined. Globules range in size from less than ½μ to over 7μ. The maximum number of globules occurs at different sizes in different sows, the largest maximum size group so far recorded being 2–2·5μ, the smallest maximum group being 0–0·5μ. There is no marked trend in size with stage of milking, though usually the maximum size is less for later milkings if it changes.The strippings of sow's milk, unlike those of the cow, do not appear to be richer in fat than the earlier milk. Also unlike the cow, the globules of sow's milk do not cluster or clump (see Fig. 1). This explains the slow rate of creaming of sow's milk.

The Life Cycle of Macrosiphum solanifolii with Special Reference to the Genetics of Color

(1) Macrosiphum solanifolii exists in two varieties, pink and green, whose color is due to globules of different colors and sizes contained in the body fluid. The several forms belonging to each of these varieties are briefly described. (2) Pink lines differ from one another somewhat in color and green lines differ from one another, owing to differences in the color and number of globules contained in the body fluid. (3) The pink color of a line commonly fades somewhat during the season; the cause of the change is unknown. (4) In green lines the sexual (oviparous) female is most often wax yellow in color, sometimes greenish; in one line, however, the sexual females were mottled with salmon-orange on the abdomen. (5) The sexual phase usually appears later in the season in pink lines than in green lines. (6) Pink parthenogenetic females produce only pink offspring. Green parthenogenetic females produce only members of the green variety, some of which, however, are not green. (7) Very few of the fertilized eggs of sexual females hatch. No treatment capable of increasing their viability has been discovered. (8) Sexual females of a green line mated with males of the same line produced mostly green offspring, but two of them were pink. (9) Sexual females of one green line mated with males of a supposedly different green line produced offspring that were mostly green, but several pink ones were included. (10) Pink sexual females mated with males of the same line produced only pink offspring. Since there were only two of these, it is thought that green offspring might also be obtained from such parents. (11) Pink sexual females mated with males from other pink lines produced both green and pink offspring. (12) Sexual females of green lines mated with males of pink lines produced only green offspring, though it is thought that pink offspring may occasionally be produced by such parents. (13) The results of the above matings appear to indicate that color in these aphids is due to multiple factors. This assumption also fits the fact that lines differ among themselves in color, even within one color variety. (14) The pink lines studied produced somewhat fewer young per day than did the green lines. (15) This difference in the rate of reproduction exhibited by the two varieties seems to be associated with the color, and not to be independently inherited. (16) Under natural conditions the pink variety probably descends chiefly, if not wholly, from the green variety each year. (17) The approximate alternation of this species between the potato and rose is probably due to the earlier growth of shoots of the rose than of the potato and to removal of the insects from the rose by rain and wind, and does not indicate any inherent property of the aphids or of their cycle. Any form belonging to the species may live and reproduce on either of the principal host plants at any time of year.

Observations on the Fat Globules in Milk

Results of our previous work were published in the Journ. of Agric. Sri., IV, 1911. There, also, a brief summary of the chief papers published on the subject of the fat globules was given, to which it is unnecessary to refer in detail here.When the work was first commenced in 1909, the problem before us was the consideration of the variation in the size of the fat globules, with relation to churning, as regards the different breeds of cattle. The breed was considered because it was usually supposed that this was one of the chief factors which influenced churning. The most definite result of our work was that it was shown that consideration must be given to the character of the milk, irrespective of the breed. This conclusion is quite contrary to that of other workers, but an examination of their figures shows, undoubtedly, that this is actually the case: the results given by Woll (Digestion Expts., Seventh Annual Report, Agric. Expt. Stat, Wisconsin, 1890, 238; also Agric. Sci., 1892, vi, 445) emphasise this point particularly. It is also shown by this year's work, as may be seen from Tables V–XI.The comparative size of the globules has been worked out very thoroughly by Gutzeit, who measured the mean volume of the globule. Other workers give their results as “relative sizes.” In our work we attempted to ascertain the distribution of the fat in the globules, and to this end the number of globules of each size was determined, and curves were drawn. The result of this, however, was negative. At that time we were considering the breeds of the cows from which the milks were obtained; had we considered them solely as milks of a certain mean size of globule, much more might have been achieved.An apparatus was devised to give an absolute figure for the churnability of any cream, but, until the effect of the other factors has been determined, it is impossible to interpret the results. Some experiments to ascertain the optimum temperature were described also.