Generation glands of cordylid lizards: mechanism of secretion transfer to the environment

2015 ◽  
Vol 36 (4) ◽  
pp. 351-360 ◽  
Author(s):  
André de Villiers ◽  
P. le Fras N. Mouton ◽  
Alexander Flemming
Keyword(s):  
Substantial Part ◽  
Routine Method ◽  
Cross Sectional ◽  
Liquid Component ◽  
Histological Techniques ◽  
Femoral Glands ◽  
Abrasion Rate ◽  
Wear And Tear ◽  
Epidermal Glands ◽  
Scanning Electron

Cordylid lizards possess two types of holocrine epidermal glands involved in chemical communication, femoral glands and generation glands. We investigated how the glandular products of generation glands are dispersed to the environment, as it is assumed in earlier studies that glandular material of cordylid generation glands is transferred to the substrate via abrasion, similar to the situation in femoral glands. By means of scanning electron microscopy, we established that the outer gland surfaces of adult Cordylus cordylus, Hemicordylus capensis and Pseudocordylus microlepidotus show only localized signs of wear and tear, indicative of a very low abrasion rate. Using standard histological techniques and light microscopy, we studied the appearance of multi-layer generation glands in a series of individuals of different ages in Cordylus macropholis. In this species, generation glands are already conspicuous in neonates. The significant relationship between SVL and the number of generation layers that we recorded for C. macropholis suggests that abrasion is not the routine method of dispersal of glandular material. We did record significant differences in cross-sectional area and height between the outer and inner layers of multi-layer generation glands of Cordylus macropholis, but this is more likely attributable to ‘desiccation’ of the outer layer, rather than abrasion. Although we found signs of abrasion in cordylid generation glands, these appear minor. Evidence seems to suggest that a substantial part of the mature glandular generations remains intact and that probably only a liquid/semi-liquid component is dispersed to the environment. More research is, however, needed to confirm this.

X-ray micro tomography in the scanning electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 106-107 ◽  
Author(s):  
W. Brünger
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Target Surface ◽  
The Body ◽  
X Rays ◽  
Cross Sectional ◽  
X Ray ◽  
Micro Tomography ◽  
Scanning Electron

Reconstructive tomography is a new technique in diagnostic radiology for imaging cross-sectional planes of the human body /1/. A collimated beam of X-rays is scanned through a thin slice of the body and the transmitted intensity is recorded by a detector giving a linear shadow graph or projection (see fig. 1). Many of these projections at different angles are used to reconstruct the body-layer, usually with the aid of a computer. The picture element size of present tomographic scanners is approximately 1.1 mm2.Micro tomography can be realized using the very fine X-ray source generated by the focused electron beam of a scanning electron microscope (see fig. 2). The translation of the X-ray source is done by a line scan of the electron beam on a polished target surface /2/. Projections at different angles are produced by rotating the object.During the registration of a single scan the electron beam is deflected in one direction only, while both deflections are operating in the display tube.

A Working Method for Adapting the (SEM) Scanning Electron Microscope to Produce (STEM) Scanning Transmission Electron Microscope Images

2002 ◽  
Author(s):  
Edward Coyne
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Scanning Electron Microscope ◽  
Integrated Circuits ◽  
Theoretical Idea ◽  
Cross Sectional ◽  
Additional Advantage ◽  
Transmission Electron ◽  
Resolution Element ◽  
Scanning Electron

Abstract This paper describes the problems encountered and solutions found to the practical objective of developing an imaging technique that would produce a more detailed analysis of IC material structures then a scanning electron microscope. To find a solution to this objective the theoretical idea of converting a standard SEM to produce a STEM image was developed. This solution would enable high magnification, material contrasting, detailed cross sectional analysis of integrated circuits with an ordinary SEM. This would provide a practical and cost effective alternative to Transmission Electron Microscopy (TEM), where the higher TEM accelerating voltages would ultimately yield a more detailed cross sectional image. An additional advantage, developed subsequent to STEM imaging was the use of EDX analysis to perform high-resolution element identification of IC cross sections. High-resolution element identification when used in conjunction with high-resolution STEM images provides an analysis technique that exceeds the capabilities of conventional SEM imaging.

scholarly journals The Influence of Blade Type and Feeding Force during Resin Bonded Dentin Specimen Preparation on the Microtensile Bond Strength Test

Micromachines ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 450
Author(s):  
Apinya Limvisitsakul ◽  
Suppason Thitthaweerat ◽  
Pisol Senawongse
Keyword(s):  
Bond Strength ◽  
Surface Integrity ◽  
Strength Test ◽  
Specimen Preparation ◽  
Sectional Area ◽  
Microtensile Bond Strength ◽  
Cross Sectional ◽  
Microtensile Testing ◽  
Feeding Force ◽  
Scanning Electron

This paper presents the effect of blade type and feeding force during resin-bonded dentin specimen preparation on the microtensile bond strength (μTBS) test. Forty resin-bonded flat middle dentin specimens were divided into four groups. The specimens of each group were sectioned according to type of blade and feeding force as follows: fine grit/20 N, fine grit/40 N, medium grit/20 N, and medium grit/40 N to obtain resin-dentin sticks with a cross-sectional area of 1.0 mm2. Four sticks from the center of each tooth were subjected to the μTBS test. Five remaining sticks of each group were selected for surface topography observation under a scanning electron microscope (SEM). As a result, the bond strength of the medium-grit group was higher than that of the fine-grit group (p < 0.001), whereas the feeding force had no influence on bond strength values (p = 0.648). From the SEM, sticks prepared with the fine-grit blade showed a smoother surface integrity and fewer defects on the specimen edges in comparison with the sticks prepared with the medium-grit blade. The grit type of the blade is one of the considerable factors that may affect the bond strength and the surface integrity of resin-dentin specimens for microtensile testing.

Characterization of Thin Polymer Blend Films using ESEM – No Charging, No Staining.

2001 ◽  
Vol 707 ◽  
Author(s):  
Ian C. Bache ◽  
Catherine M. Ramsdale ◽  
D. Steve Thomas ◽  
Ana-Claudia Arias ◽  
J. Devin MacKenzie ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Environmental Scanning Electron Microscopy ◽  
Environmental Scanning ◽  
Cross Sectional ◽  
Blend Films ◽  
Thin Polymer ◽  
Device Applications ◽  
Scanning Electron

ABSTRACTCharacterising the morphology of thin films for use in device applications requires the ability to study both the structure within the plane of the film, and also through its thickness. Environmental scanning electron microscopy has proved to be a fruitful technique for the study of such films both because contrast can be seen within the film without the need for staining (as is conventionally done for electron microscopy), and because cross-sectional images can be obtained without charging artefacts. The application of ESEM to a particular blend of relevance to photovoltaics is described.

Perioperative Use of Total Parenteral Nutrition: Variations in Guidelines and Practice in Three Norwegian Hospitals

1995 ◽  
Vol 11 (4) ◽  
pp. 741-749 ◽  
Author(s):  
Marianne Mjaaland ◽  
Arthur Revhaug ◽  
Olav Helge Førde
Keyword(s):  
Retrospective Study ◽  
Parenteral Nutrition ◽  
Total Parenteral Nutrition ◽  
Gastrointestinal Surgery ◽  
Patient Characteristics ◽  
Substantial Part ◽  
Cross Sectional

AbstractIn a cross-sectional, retrospective study of 604 cases, variations among three Norwegian hospitals in use of perioperative parenteral nutrition (TPN) after gastrointestinal surgery was determined. Postoperative TPN rates were 25%, 34% (p =.05) and 56% (p <.0001). respectively. However, a substantial part of the variation was explained by differences in patient characteristics.

A histological examination of the holding sacs and glandular scent organs of some bat species (Emballonuridae, Hipposideridae, Phyllostomidae, Vespertilionidae, and Molossidae)

2000 ◽  
Vol 78 (4) ◽  
pp. 613-623 ◽  
Author(s):  
William MR Scully ◽  
M B Fenton ◽  
A SM Saleuddin
Keyword(s):  
Electron Microscope ◽  
Sexual Dimorphism ◽  
Sebaceous Glands ◽  
Microscope Examination ◽  
Scent Gland ◽  
Light Microscope Level ◽  
Histological Techniques ◽  
Saccopteryx Bilineata ◽  
The Face ◽  
Scanning Electron

Using histological techniques at the light-microscope level, we examined and compared structure and sexual dimorphism of the wing sacs and integumentary glandular scent organs of 11 species of microchiropteran bats. The antebrachial wing sacs of the Neotropical emballonurids Peropteryx macrotis, Saccopteryx bilineata, and Saccopteryx leptura differed in size and location but lacked sudoriferous and sebaceous glands, confirming that they were holding sacs rather than glandular scent organs. Glandular scent organs from 11 species consisted of sebaceous and (or) sudoriferous glands in emballonurids (P. macrotis, S. bilineata, S. leptura, Taphozous melanopogon, Taphozous nudiventris), hipposiderids (Hipposiderous fulvus, Hipposiderous ater), the phyllostomid Sturnira lilium, the vespertilionid Rhogeessa anaeus, and molossids (Molossus ater and Molossus sinaloe). Glandular scent organs were located on the face (H. fulvus, H. ater), gular region (S. bilineata, P. macrotis, T. melanopogon, M. ater, M. sinaloe), chest (T. nudiventris), shoulder (S. lilium), or ears (R. anaeus). Glandular scent organs showed greater similarities within than between families, and typically were rudimentary or lacking in females. Scanning electron microscope examination revealed that the hairs associated with glandular areas of male T. melanopogon were larger and had a different cuticular-scale pattern than body hairs. These were osmetrichia, hairs specialized for holding and dispersing glandular products. In S. lilium, hairs associated with the shoulder scent-gland area were larger than body hairs but similar in cuticular-scale pattern.

scholarly journals Assessment of the technical condition of lift guides using a magnetic field

2021 ◽  
Vol 2130 (1) ◽  
pp. 012003
Author(s):  
P Lonkwic ◽  
T Krakowski ◽  
H Ruta
Keyword(s):  
Early Stage ◽  
Technical Condition ◽  
Operating Conditions ◽  
Measuring Head ◽  
Cross Sectional ◽  
Correct Operation ◽  
Emergency Braking ◽  
Wear And Tear ◽  
Equipment Failures ◽  
Novel Concept

Abstract The systems that monitor individual components of machines and devices are under constant development. The ability to detect damages at an early stage allows failures to be prevented, so any uncontrolled downtime can be predicted in a controlled manner. Continuous monitoring of technical condition is an activity that also helps to reduce the losses due to equipment failures. However, not all areas can be monitored continuously. Such areas include lift guides where wear and tear can occur naturally, i.e. through abrasion of the material layer due to interaction with moving guide shoes or after emergency braking. Emergency braking causes local damages to the guide through plastic deformation of its surface resulting from indentation of the knurled roller of the brake. Such places are cleaned mechanically, which results in local reduction of the cross-sectional area. In such a case, it is difficult to continuously assess the technical condition of guides due to the prevailing operating conditions. Therefore, a concept of a head enabling assessment of the technical condition of guides at every stage of their operation has been developed. This article presents the novel concept of a magnetic head used for assessing the technical condition of lift guide rails that are the running track of lifting equipment. The initial tests were performed on the original test setup. The concept of the developed measuring head was verified for correct operation on specially prepared flat bars with holes. The results obtained in the form of laboratory tests proved that the proposed measuring head concept can be applied to the measurements under real conditions.

Stability and Performance Study of Polyethersulfone Membranes Modified Using Polyelectrolytes

2013 ◽  
Vol 65 (4) ◽  
Author(s):  
Law Yong Ng ◽  
Abdul Wahab Mohammad ◽  
Ching Yin Ng ◽  
Nur Hanis Hayati Hairom
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Research Work ◽  
Performance Study ◽  
Salt Solutions ◽  
Cross Sectional ◽  
And Performance ◽  
Surface Modified ◽  
Lower Contact ◽  
Scanning Electron

In this research work, porous PES membranes were initially pre-heated for certain duration of time and then surface-modified to reject the MgSO4 salt solutions through self-adsorption of polyelectrolytes. From the experimental work, higher membrane salt rejection capability can be obtained when the number of polyelectrolyte bilayers is increased. The images of the cross-sectional morphology of modified and non-modified membranes were obtained using field emission scanning electron microscopy (FESEM). All modified membranes showed relatively lower contact angle values.

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