scholarly journals Diversity of functional microornamentation in slithering geckos Lialis (Pygopodidae)

2013 ◽  
Vol 280 (1772) ◽  
pp. 20132160 ◽  
Author(s):  
M. Spinner ◽  
S. N. Gorb ◽  
G. Westhoff

The skin of geckos is covered with countless microscopic protuberances (spines). This surface structure causes low wettability to water. During evolution, representatives of the recent gekkotan clade Pygopodidae started slithering on the ground. This manner of locomotion affected limb reduction resulting in a snake-like body. Regarding abrasion and frictional properties, a surface covered with gekkotan spines is a topography that hampers the snake-like locomotion mode. Using scanning electron microscopy, we investigated the shed skins of two pygopodid lizards, Lialis jicari (Papua snake lizard) and Lialis burtonis (Burton's legless lizard), in order to show epidermal adaptations to limbless locomotion. Our data showed that Pygopodidae differ from their relatives not only anatomically, but also in their epidermal microstructure. Scales of L. jicari have five different structural patterns on various body regions. Ventral scales have nanoridges, similar to those found on the ventralia of snakes. Surfaces of scales covering the jaw bones, have flattened spine-like microstructures that might be an adaptation to reduce abrasion. Dorsal scales have oblong microscopic bulges covered with nanoridges. Spines cover the undersides and the interstices of scales over the entire body of both species and in L. jicari also the top of dorsal head scales. Our measurements of surface wettability (surface free energy) show superhydrophobic properties of the spiny surfaces in comparison with the other microstructural patterns of other body parts.

2016 ◽  
Vol 30 (1) ◽  
pp. 29
Author(s):  
Sarodee Boruah ◽  
Pranab Dutta ◽  
Joyarani Pegu ◽  
Himadri Kaushik ◽  
N. Gogoi ◽  
...  

Morphological changes in <em>Metarhizuim anisopliae</em> (Metschnikoff) Sorokin infected cow pea aphid, <em>Aphis craccivora</em> Koch were studied by scanning electron microscope (SEM). Aphids were caged on paired lantern chimney over cowpea twigs dipped in conical flasks with water infected and inoculated with fungal propagules of <em>M. anisopliae</em> at the concentration of 1X10<sup>6</sup> spores /ml of water. Infected aphids were observed under SEM and it showed severe cuticular damage, abnormalities in sensory systems as well as deformation of all the body parts. The hydrophobic conidia of <em>M. anisopliae</em> were found to attach to all body regions. It was evident that mycelial growth and conidiophores with conidia of <em>M. anisopliae</em> covered the body surface and penetrates inside the body of infested aphid causing damage to the pest by disturbing its major physiological activities leading to its death.


2021 ◽  
pp. X
Author(s):  
Zhenyu WANG ◽  
Jie WANG ◽  
Fenghong CAO ◽  
Yunhai MA

Carbonization treatment contributes to improvement of tribological properties of friction composites. Pure Non-asbestos organic (NAO) friction raw materials were selected, friction composite specimens had been made using a new mixing process and carbonization treatment. Two types of specimens had been prepared to evaluate their performance, one was carbonized a pure non-asbestos organic friction composite specimen and the other was an original brake metal linings of a certain brand of vehicles. Two friction composites were evaluated by brake inertia dynamometer. Their performances were assessed according to the procedure in a European Union Automobile Standards (AK Master). Microscopic photographs of worn surfaces were obtained by scanning electron microscopy to characterize their tribological behavior and wear mechanism. The results showed that pure NAO friction composites had more suitable frictional properties, fade and recovery behavior than the copper-containing metal brake pad, but wear resistance was slightly lower. Carbonation promoted the formation of microporous structure in friction composites, which was helpful to reduce noise and vibration during work.


Author(s):  
R. E. Ferrell ◽  
G. G. Paulson

The pore spaces in sandstones are the result of the original depositional fabric and the degree of post-depositional alteration that the rock has experienced. The largest pore volumes are present in coarse-grained, well-sorted materials with high sphericity. The chief mechanisms which alter the shape and size of the pores are precipitation of cementing agents and the dissolution of soluble components. Each process may operate alone or in combination with the other, or there may be several generations of cementation and solution.The scanning electron microscope has ‘been used in this study to reveal the morphology of the pore spaces in a variety of moderate porosity, orthoquartzites.


1987 ◽  
Vol 26 (05) ◽  
pp. 202-205 ◽  
Author(s):  
J. Fass ◽  
S. Truong ◽  
U. Büll ◽  
V. Schumpelick ◽  
R. Bares

Radioimmunoscintigraphy (RIS) with 111ln- and 131 I-labelled monoclonal anti bodies (MAbs) against CEA and/or CA 19-9 was performed in 83 patients with various gastrointestinal carcinomas. A total of 276 body regions could be examined. The results of planar scintigraphy and SPECT were compared intraindividually. Using 111 In-labelled MAbs the sensitivity of RIS was significantly improved by SPECT (88.9 vs. 52.4% with planar scintigraphy, p <0.01). For131 l-labelled MAbs the effect was smaller (83.9 vs. 65.6% with planar scintigraphy, n.s.). This finding can be explained by different kinetics and biodistribution of the used MAb preparations.111 In-labelled MAbs with long whole-body retention and rapid blood clearance reveal ideal qualities for SPECT; on the other hand, the short whole-body retention of131 l-labelled MAbs leads to small count rates and therefore long counting times that make delayed SPECT unsuitable in clinical practice


1989 ◽  
Vol 35 (12) ◽  
pp. 1081-1086 ◽  
Author(s):  
Byron F. Johnson ◽  
L. C. Sowden ◽  
Teena Walker ◽  
Bong Y. Yoo ◽  
Gode B. Calleja

The surfaces of flocculent and nonflocculent yeast cells have been examined by electron microscopy. Nonextractive preparative procedures for scanning electron microscopy allow comparison in which sharp or softened images of surface details (scars, etc.) are the criteria for relative abundance of flocculum material. Asexually flocculent budding-yeast cells cannot be distinguished from nonflocculent budding-yeast cells in scanning electron micrographs because the scar details of both are well resolved, being hard and sharp. On the other hand, flocculent fission-yeast cells are readily distinguished from nonflocculent cells because fission scars are mostly soft or obscured on flocculent cells, but sharp on nonflocculent cells. Sexually and asexually flocculent fission-yeast cells cannot be distinguished from one another as both are heavily clad in "mucilaginous" or "hairy" coverings. Examination of lightly extracted and heavily extracted flocculent fission-yeast cells by transmission electron microscopy provides micrographs consistent with the scanning electron micrographs.Key words: flocculation, budding yeast, fission yeast, scanning, transmission.


2018 ◽  
Vol 197 ◽  
pp. 06006 ◽  
Author(s):  
Renaldi Ednin Vernia ◽  
Anais Tritto ◽  
Abinawanto Abinawanto ◽  
Nurul Winarni ◽  
Anita mayasari ◽  
...  

Black-winged myna (Acridotheres melanopterus) is an endemic bird of Java and Bali, currently critically endangered based on International Union of Conservation for Nature (IUCN) since 2010. The study about black-winged myna morphological characteristic is important because it has two relatives with almost identical features of morphology. The information can be used as a basis in breeding management to avoid hybridization. The study aims to determine the morphological characteristics of black-winged myna. The sample selection was done using purposive sampling method. Data was taken from 36 black-winged mynas with >=2 years old. Data collection was done by measuring and documenting every morphological feature of the observed body parts. Documentation of the wings, back, chest, head and sides of the body are taken from each bird using a digital camera. The results showed that almost the entire body of black-winged myna covered by white feather, black feather only present on the cover of the wings and tail. Black eyes surrounded by yellow skin without feather. The beak is orange with blackish parts around the nostrils. The bird has yellow legs with three fingers at the front and one finger at the back. The average body length of this bird is 22.5 cm, weight 89.02 g, width 5.98 cm, body circumference 14.36 cm and wingspan 38.49 cm.


Author(s):  
Anna Zhadan

Two new species of Cossura Webster & Benedict, 1887 were found in material collected during sampling from the terminal lobes of the Congo deep-sea fan. They were described using light and scanning electron microscopy. Cossura platypus sp. nov. has 15–17 thoracic chaetigers, a prostomium longer than it is wide, with a widely rounded anterior margin, an abruptly expanded posterior prostomial ring the same length as the peristomium, without a mid-ventral notch, a branchial filament attached to the midlength of chaetiger 3, and a pygidium with three anal cirri. Cossura platypus sp. nov. is similar to C. brunnea Fauchald, 1972 but differs in the shape of the prostomium, which is widely rounded anteriorly in C. platypus sp. nov. and is broadly triangular in C. brunnea; furthermore, C. platypus sp. nov.is uniformly pale, whereas C. brunnea has dark pigmentation. Cossura candida Hartman, 1955 differs from C. platypus sp. nov. in the conical shape of the prostomium and 24–35 thoracic chaetigers. Cossura flabelligera sp. nov. has 16–19 thoracic chaetigers, a conical prostomium, and a branchial filament arising from the posterior part of chaetiger 2; the entire body, including the chaetae, is covered by a thick mucous sheath similar to the tunic of flabelligerids. Cossura flabelligera sp. nov. resembles C. longocirrata Webster & Benedict, 1887 in the position of the branchial filament, the shape of the prostomium, and the number of thoracic chaetigers; it differs in having a thick mucous sheath. This character seems to be unique for the Cossuridae.


2017 ◽  
Vol 62 (2) ◽  
pp. 1005-1010 ◽  
Author(s):  
Peyala Dharmaiah ◽  
C.H. Lee ◽  
B. Madavali ◽  
Soon-Jik Hong

AbstractIn the present work, we have prepared Bi2Te3nanostructures with different morphologies such as nano-spherical, nanoplates and nanoflakes obtained using various surfactant additions (EG, PVP, and EDTA) by a hydrothermal method. The shape of the nanoparticles can be controlled by addition of surfactants. The samples were characterized by x-ray diffraction (XRD) and scanning electron microscopy (SEM). It is found that the minority BiOCl phase disappears after maintained pH at 10 with EG as surfactant. SEM bulk microstructure reveals that the sample consists of fine and coarse grains. Temperature dependence of thermoelectric properties of the nanostructured bulk sample was investigated in the range of 300-450K. The presence of nanograins in the bulk sample exhibits a reduction of thermal conductivity and less effect on electrical conductivity. As a result, a figure of merit of the sintered bulk sample reached 0.2 at 400 K. A maximum micro Vickers hardness of 102 Hv was obtained for the nanostructured sample, which was higher than the other reported results.


2018 ◽  
Author(s):  
Jianyu Li ◽  
Mengzhu Shi ◽  
Yuechao He ◽  
Jianwei Fu ◽  
Lizhen Zheng

Background. Phyllotreta striolata is a worldwide pest that harms cruciferous vegetables. The use of pathogenic microorganisms to control pests is an important means of biological control. Using pathogenic microorganisms to prevent and control P. striolata has rarely been reported. Methods. In this study, the infection process of a Metarhizium strain highly pathogenic to P. striolata was observed by stereomicroscopyand scanning electron microscopy (SEM). Results.The results showed that the attachment of Metarhizium strain Ma6 to the body surface varied; the conidia distribution was greatest in the tibia of the posterior leg with thick bristles and in the intersegmental abdominal membrane, and the spore distribution occurred least in the smooth and hard portions of the insect’s body. At the start of the infection, Metarhizium strain Ma6 generally grew from the body parts with gaps or connecting spaces such as mouthparts and the thoracic leg base and joints, then the spores germinated with germ tubes and penetration peg, and the penetration peg penetrated the body surface. Ten days after inoculation, the mycelia divided into conidia, and many mycelia and spores covered the entire adult insect’s body. Discussion. Spore germination occurred on the 5th day after inoculation, and many hyphae and spores covered the entire adult insect body within 10 days after inoculation. And the invasion into tissue gaps from the weaker areas is more efficient than intruding from the body hard surface. This may be the reason for the Metarhizium strain Ma6’s high virulence. This study preliminarily clarified the infection ability and invasion approach of a Metarhizium strain against P. striolata, providing evidence for evaluating the strain’s insecticidal effect and application prospect.


Author(s):  
Emilia Szalkowska-Kim

This article presents the results of comparative research into the collocations of the names of human body parts with dimension adjectives. The aim of the analysis was to indicate the similarities, limitations and differences in the manners of conceptualising the world established in Polish and Korean, or more precisely: how both languages define the elements of the world of human body parts, and how they assign dimensions to the elements depending on the needs and experiences of native users of both. The results of the research could have a practical application in teaching both languages, facilitating students’ absorption of the lexis of the other language, and result in a deeper mutual understanding of linguistic and cultural differences..


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