scholarly journals III.—Notes on the composition of Clays, Slates, etc., And on some points in their Contact-Metamorphism

1894 ◽  
Vol 1 (2) ◽  
pp. 64-75
Author(s):  
W. Maynard Hutchings
Keyword(s):  
Polarized Light ◽  
White Mica ◽  
The Other ◽  
Contact Metamorphism ◽  
Stages Of Development ◽  
Characteristic Appearance ◽  
Definite Form ◽  
Yellow Substance ◽  
Ordinary Light ◽  
Other Substances

After this substance has been well observed in good occurrences, it is always recognized at once, even as isolated small patches in a slide. It has a very characteristic appearance among the other constituents. It is marked off, for instance, by its special refraction from anything else that occurs in these rocks, and has other characteristics not to be missed when once observed, but not very easy to exactly describe. As soon as it ceases to be quite inert in polarized light, as soon as the speckly polarization sets in, it has also a more or less granular appearance in ordinary light with lowered condenser, which is very characteristic.indifferent slides, and often in one and the same slide, various stages of development may be observed in it from the first speckled appearance in polarized light up to a point where flakelets of white mica are recognized as forminginit, lying “criss-cross”inall directions. It passes in this way in some cases almost wholly into mica, with apparently other substances which cannot be identified with certainty, the transition, and connection with the original substance, being all the time distinct and beyond mistake.In the inner zones, the “hornfels-zones,“ this substance is usually present in smaller amount, as already stated; but examples of its abundant occurrence are not wanting, as for instance in a hornfels from Spitzenberg, in the Harz. There is a mosaic of quartz and felspar, with brown mica and some white mica. The yellow substance lies in amongst, and surrounds, the minerals of this mosaic. It has no definite form of its own, simply occupying spaces and taking the outlines of the other minerals. It is all either in the minutely-speckly stage or variously developed from this upwards to mica; and the impression made is that if it had all developed as far as some portions of it have done, the whole mosaic-grains of the slides would be mixed in with and surrounded by white mica, as may not infrequently be observed in these contact-rocks.

scholarly journals Dermoscopic aspect of verrucous epidermal nevi: New findings

2019 ◽  
Author(s):  
ÖMER FARUK ELMAS ◽  
NECMETTİN AKDENİZ
Keyword(s):  
Polarized Light ◽  
Diagnostic Methods ◽  
The Other ◽  
Diagnostic Process ◽  
Fine Scale ◽  
Epidermal Nevus ◽  
Clinical Interpretation ◽  
New Findings ◽  
Clinical Variants ◽  
Histopathological Investigation

Background and Aim: Verrucous epidermal nevi are cutaneous hamartomas having many clinical variants. Dermoscopic features of verrucous epidermal nevus have rarely been investigated. We aimed to identify dermoscopic findings of the entity which will facilitate the diagnostic process by reducing the use of invasive diagnostic methods. Material and Methods: The study included the patients with histopathologically approved verrucous epidermal nevus. Clinical, dermoscopic and histopathological features of the patients were retrospectively reviewed and the findings identified were recorded. Dermoscopic examination was performed with a polarized-light handheld dermoscope with 10-fold magnification. Results: The most common dermoscopic features were thick brown circles, thick brown branched lines and terminal hairs. The most common vessel pattern was dotted vessels. Branched thick brown lines, brown globules, brown dots forming lines, serpiginous brown dots, white and brown exophytic papillary structures, fine scale, thick adherent scale and cerebriform structures were the other findings. Conclusion: We observed many vascular and non-vascular dermoscopic findings which have not been described previously for the entity. Dermoscopic examination of the verrucous epidermal nevi may lead more reliable clinical interpretation and thus it may reduce the need for histopathological investigation. Keywords: dermoscopy, large brown circles, verrucous epidermal nevus

scholarly journals Exploiting the Binocular Head in Polarized Light Microscopy

1994 ◽  
Vol 2 (4) ◽  
pp. 16-16
Author(s):  
Walter C. McCrone
Keyword(s):  
Light Microscopy ◽  
Polarized Light ◽  
Polarized Light Microscopy ◽  
The Other ◽  
Monocular Viewing ◽  
Area Of Interest

Having been brought up on monocular microscopes I find the omnipresent binocular systems a luxury. To support this viewpoint I'd like to suggest some benefits you may not have considered.Because I'm used to monocular viewing I sometimes use two different oculars, say 10X and 25X, in order to scan quickly to find an area of interest and then to examine the detail with higher magnification. Occasionally I use both oculars simultaneously and “concentrate” on either image to the exclusion of the other. A better way is to set the interocular distance at the extreme setting most different from your own interocular distance. By moving your head about a centimeter either way you can use either ocular.

Comparative leaf development of aerial and aquatic growth forms of Myriophyllum aquaticum

Botany ◽  
2013 ◽  
Vol 91 (7) ◽  
pp. 421-430 ◽  
Author(s):  
M.D. Shafiullah ◽  
Christian R. Lacroix
Keyword(s):  
Apical Meristem ◽  
Epidermal Cells ◽  
The Other ◽  
Developmental Study ◽  
Growth Forms ◽  
Myriophyllum Aquaticum ◽  
Stages Of Development ◽  
Qualitative And Quantitative ◽  
Early Stages ◽  
Other Hand

Myriophyllum aquaticum (Vell.) Verdc. produces two morphologically different forms of leaves based on whether they are aerial or aquatic. The objective of this study was to determine whether there are any similarities or differences between these two growth forms during their early stages of development. A comparative developmental study of aerial and aquatic growth forms of M. aquaticum was conducted from a qualitative and quantitative perspective using a scanning electron microscope. The pattern of leaf and lobe initiation such as their origin and shape were similar in both growth forms until the fourth plastochron (stage P4). Differences between the two growth forms became evident from stage P5 onward, where a larger shoot apical meristem (SAM), elongated epidermal cells, shorter and slightly more numerous lobes, as well as the presence of appendage-like structures characterized aquatic growth forms. On the other hand, aerial growth forms had smaller SAM, bulb-like epidermal cells, and longer and slightly less numerous leaf lobes. Significant differences between growth forms were noted for parameters such as volume of SAM, length of terminal, first, and middle lobes, as well as the length from first to last lobes. The volume of the SAM of aquatic shoot tips was always greater than aerial forms. On the other hand, lobes of aerial forms were always longer than the aquatic counterpart during early stages of development. This study on the development of M. aquaticum shows that the aerial and aquatic growth forms diverge from their early stages of development.

XV. On the development of the parasitic isopoda

1878 ◽  
Vol 169 ◽  
pp. 505-521 ◽  
Keyword(s):  
The Body ◽  
The Other ◽  
Stages Of Development ◽  
Early Stages ◽  
Abdominal Appendages ◽  
Pair Of Antennae

The following paper contains an account of observations on the development of the species Cymothoa œstroides and C . parallela of Milne Edwards; but the forms of the young seem to show that several species are really included under these two names. In the early stages of development the only observable difference that exists between the embryos is one of size, but in the later stages they differ very markedly from each other in their external characters. From adult individuals answering the description of C . œstroides I have obtained four varieties of embryos: two with long antennae and two with short.* In the two former the first pair of antennae are but slightly longer than the head, while the second pair are longer than the body; the eyes are small. In one of the varieties thus characterised the abdominal appendages are fringed with long hairs (fig. 20), and in the other they are smooth.

An Examination of Baker's Acid Haematein Test for Phospholipines

1947 ◽  
Vol s3-88 (4) ◽  
pp. 467-478
Author(s):  
A. J. CAIN
Keyword(s):  
Calcium Ions ◽  
The Other ◽  
Blue Staining ◽  
Other Substances ◽  
Whole Class ◽  
Dark Blue ◽  
General Explanation

1. Baker's acid haematein test for phospholipines is specific provided that only a definite positively result is considered. Very pale blues and greys may be caused by other lipoids, which if present in very large masses may possibly show medium to dark blue granules but will not be coloured all through. 2. The mechanism of the test appears to be as follows: (a) Phospholipine is not fixed by formal-calcium but is restrained from passing into solution by the calcium ions, which play no other part. (b) Phospholipine combines readily with chromium from the mordanting fluid, and is then rendered insoluble and mordanted. Other substances, acidic and usually containing phosphorus, are mordanted as well. (c) On staining, blue and brown colorations are formed; in both cases the dye attaches itself to the chromium in the various substrates. (d) On differentiation, some browns and most blues, particularly those with phosphoric substrates, remain nearly fast, but most browns and the weak blues of certain lipoids (not phospholipines) are greatly reduced or removed entirely. The period of differentiation must not be shortened. (e) Blue-staining lipoids (phospholipines) are distinguished from other blue-staining substances by an extraction with the lipoid solvent pyridine, after special fixation. The other substances, and any bound lipoid not removable with pyridine, remain. 3. Since the specificity of the test depends on the relatively greater affinity of phospholipines among lipoids for the mordant, the period of chroming must not be lengthened. 4. One reason why some substances are coloured after pyridine extraction but not after acid haematein is that in the former case they are precipitated and so concentrated; in the latter they are not. This is not a general explanation for the whole class of such substances.

scholarly journals The comprehension of deictic terms in normal and language impaired children

1981 ◽  
Vol 28 (1) ◽  
Author(s):  
Michelle Mentis
Keyword(s):  
Qualitative Analysis ◽  
The Other ◽  
Developmental Sequence ◽  
Stages Of Development ◽  
Normal Children ◽  
Language Impaired ◽  
Semantic Complexity ◽  
Impaired Group ◽  
Age Range ◽  
Impaired Children

This study examined the comprehension of four pairs of deictic terms in a group of language impaired children and compared their interpretation of these terms with those of non-language impaired children of the same age range. Each group was comprised of ten subjects within the age range of 9,6 to 10,6 years. Two tasks were administered, one to assess the comprehension of the terms here, there, this, and that and the other to assess the comprehension of the terms, come, go, bring and take. The results showed that while the non-language impaired subjects comprehended the full deictic contrast between the pairs of terms tested, the language impaired group did not. A qualitative analysis of the data revealed that the language impaired subjects appeared to follow the same developmental sequence as normal children in their acquisition of these terms and responded by using the same strategies that younger non-language impaired children use at equivalent stages of development. Furthermore, the language impaired subjects appeared to comprehend the deictic terms in a predictable order based on their relative semantic complexity.

Method for the Quantification of Alginate in Microcapsules

1993 ◽  
Vol 2 (5) ◽  
pp. 429-436 ◽  
Author(s):  
Jean-Pierre Hallé ◽  
Danielle Landry ◽  
Alain Fournier ◽  
Michèle Beaudry ◽  
Francois A. Leblond
Keyword(s):  
Methylene Blue ◽  
Alkaline Medium ◽  
High Sensitivity ◽  
Sodium Concentration ◽  
The Other ◽  
Sensitive Assay ◽  
Reliable Measurement ◽  
Alginate Concentration ◽  
Other Substances ◽  
Alginate Content

Alginate is a key reagent in the preparation of microcapsules for cell transplantation. To address the question of the intracapsular alginate concentration, a sensitive assay has been developed to quantify the alginate content of microcapsules. The method is based on the metachromatic change induced by alginate binding to the dye, 1,9-dimethyl methylene blue (DMMB). The assay has a high sensitivity and precision. It covers a wide concentration range enabling the measurement of alginate in dilute supernatants as well as in microcapsules. For the latter, the membrane is initially dissolved by incubating the microcapsules in an alkaline medium. The effect of potentially interfering substances (poly-l-lysine (PLL), citrate, chloride, sodium) and of pH has been studied. Poly-l-lysine interfered with the assay at pH 6.5 but not at pH 13. Interference by sodium augmented with increasing sodium concentration and reached a plateau at 200 mM. This problem was overcome by routinely adjusting all samples to 500 mM sodium. The other substances tested had a negligible effect on the assay. The reliable measurement of alginate with this new assay will allow the optimization of the intracapsular alginate concentration.

An in vitro Evaluation of Artificial Caries-like Lesions on Restored Overdenture Abutments

1988 ◽  
Vol 67 (3) ◽  
pp. 582-584 ◽  
Author(s):  
P.P. Kambhu ◽  
R.L. Ettinger ◽  
J.S. Wefel
Keyword(s):  
Light Microscopy ◽  
Polarized Light ◽  
Polarized Light Microscopy ◽  
The Other ◽  
Type Ii ◽  
Restorative Materials ◽  
Abutment Teeth ◽  
The Mean ◽  
Materials Used

An acidified dialyzed gelatin gel system was used to determine the caries resistance of a variety of restorative materials used to obturate the canal orifice of overdenture abutment teeth. The restorative materials used were Tytin, Tytin + Copalite, P30 + Scotchbond, Fuji Ionomer-Type II, and Miracle Mix. Polarized light microscopy and microradiography were used to examine the caries-like lesions adjacent to the restorations. The lesions formed in the Fuji Ionomer-Type II and Miracle Mix groups appeared arrested at the wall adjacent to the restoration, and did not penetrate apically down the wall as did those associated with the other restorative materials. The mean depths of lesions adjacent to Fuji Ionomer-Type II and Miracle Mix restorations were significantly less than those of Tytin, Tytin + Copalite, or P30 + Scotchbond.

scholarly journals Studies on Amphibian Metamorphosis

1939 ◽  
Vol 16 (1) ◽  
pp. 96-120
Author(s):  
O. M. HELFF
Keyword(s):  
Great Majority ◽  
Gill Tissue ◽  
Shoulder Girdle ◽  
The Other ◽  
Histological Structure ◽  
Serial Sections ◽  
Stages Of Development ◽  
Amphibian Metamorphosis ◽  
The Right ◽  
Made In

(1) Opercular integument, homoplastically transplanted to the back and side of R. temporaria larvae, underwent a process of partial degeneration. The histolysis was not confined to any localized region of the transplant. (2) Autoplastic transplantation of opercular integument to the back and side produced a variety of results. Normal histological structure was maintained in certain transplants, generalized degeneration was observed in others, while in several instances localized histolysis resulting in perforation formation occurred. (3) Homoplastic and autoplastic transplantation of back and side skin to the opercular region resulted in histolysis and perforation formation in such transplants during larval involution. (4) The right forelimbs (in early stages of development) with attached portions of the shoulder girdle were extirpated in R. temporaria and B. bufo. During subsequent metamorphosis, normal opercular histolysis followed by perforation formation in many cases was observed. In most instances, serial sections of the peribranchial cavity revealed the absence of cutaneous glands. (5) Extirpation of the right forelimb only was made in the same two species. Opercular histolysis subsequently occurred in all instances, resulting in perforation formation in the great majority of cases during larval involution. In many of the B. bufo animals two separate perforations developed, one filled with limb stump and the other with gill tissue. (6) It is concluded that in R. temporaria a particular area of the operculum may in some individuals possess self-degenerative potentialities conducive to histolysis and perforation formation during metamorphosis. In both R. temporaria and B. bufo histolytic influences emanating from the atrophying gill tissue and the cutaneous glands of the forelimb are probably also responsible for opercular histolysis and perforation formation. Limb pressure must be considered a supplemental factor. (7) The results are discussed in general and attention called to the fact that opercular histolysis and perforation formation are "doubly assured" in some species and possibly even "triply assured" in others. Emphasis is placed on the evidently wide divergence between species as regards the particular combination of factors responsible for opercular histolysis and perforation formation. Apparently, no one explanation can serve to account for the phenomenon as it occurs in various species of anurans.

scholarly journals Protein supplements between consumer's opinion and quality control: an applied study in jordan

2019 ◽  
Vol 10 (3) ◽  
pp. 1961-1969
Author(s):  
Talal Aburjai ◽  
Rudaina Othman Yousif ◽  
Mahmood Jasim AlSamydai ◽  
Ali Al-Samydai ◽  
Farah Al-Mamoori ◽  
...  
Keyword(s):  
High Performance ◽  
Chromatographic Method ◽  
The Other ◽  
Primary Study ◽  
Fast Method ◽  
Reverse Phase ◽  
Protein Supplements ◽  
Sports Clubs ◽  
Applied Study ◽  
Other Substances

The consumption of dietary supplements has nowadays become popular, especially in Jordanian sports clubs and gyms. In fact, there is a widespread idea, among consumers, that these proteins contain hormones in order to increase their efficiency. The objective of this study is to develop a better understanding of customer opinion in an era that increased growth in Jordan and improves a chromatographic method to detect the testosterone in protein supplements. The method of this study, six popular types of proteins in the Jordan market have been chosen after conducting a primary study of the proteins' users by questionnaires to identify their opinions about these proteins. These proteins have been analyzed by reverse-phase high-performance liquid chromatography by developing an easy and fast method to detect testosterone signal between 8-9 minutes of the chromatogram. The results of the study showed that 61% of the users believe that sport proteins contain hormones and other substances that are not mentioned in the list of ingredients. While 39% believe otherwise. On the other side, HPLC results of six proteins showed no signs for testosterone hormone. The main reason that drives them to take sport proteins is for building muscles in spite of they believe it could be harmful due to containing hormones and other substances. So in future investigations, it might be possible to use different brands and investigate them by using the same method.

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