scholarly journals Functional consequences of convergently evolved microscopic skin features on snake locomotion

2021 ◽  
Vol 118 (6) ◽  
pp. e2018264118
Author(s):  
Jennifer M. Rieser ◽  
Tai-De Li ◽  
Jessica L. Tingle ◽  
Daniel I. Goldman ◽  
Joseph R. Mendelson
Keyword(s):  
Integrated Approach ◽  
Ventral Surface ◽  
The Body ◽  
Body Contact ◽  
Force Microscopy ◽  
Atomic Force ◽  
Biological Surfaces ◽  
Lateral Undulation ◽  
Functional Consequences ◽  
Ventral Skin

The small structures that decorate biological surfaces can significantly affect behavior, yet the diversity of animal–environment interactions essential for survival makes ascribing functions to structures challenging. Microscopic skin textures may be particularly important for snakes and other limbless locomotors, where substrate interactions are mediated solely through body contact. While previous studies have characterized ventral surface features of some snake species, the functional consequences of these textures are not fully understood. Here, we perform a comparative study, combining atomic force microscopy measurements with mathematical modeling to generate predictions that link microscopic textures to locomotor performance. We discover an evolutionary convergence in the ventral skin structures of a few sidewinding specialist vipers that inhabit sandy deserts—an isotropic texture that is distinct from the head-to-tail-oriented, micrometer-sized spikes observed on a phylogenetically broad sampling of nonsidewinding vipers and other snakes from diverse habitats and wide geographic range. A mathematical model that relates structural directionality to frictional anisotropy reveals that isotropy enhances movement during sidewinding, whereas anisotropy improves movement during slithering via lateral undulation of the body. Our results highlight how an integrated approach can provide quantitative predictions for structure–function relationships and insights into behavioral and evolutionary adaptations in biological systems.

scholarly journals First identification of nanoparticles on thorax, abdomen and wings of the worker bee Apis dorsata Fabricius

2016 ◽  
Vol 60 (1) ◽  
pp. 87-96
Author(s):  
Atanu Bhattacharyya ◽  
Shashidhar Viraktamath ◽  
Fani Hatjina ◽  
Santanu Bhattacharyya ◽  
Bhaktibhavana Rajankar ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Average Diameter ◽  
The Body ◽  
Apis Dorsata ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Calcium Phosphate Nanoparticles ◽  
First Time

Abstract The presence of nanoparticles on the body of the honeybee Apis dorsata Fabricius, was investigated for the first time to better understand the bee’s behaviour. These have been observed by using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and confirmed by Atomic Force Microscopy (AFM). Our study clearly denotes that the Indian rock honey bee Apis dorsata possess calcium silicate and calcium phosphate nanoparticles on its body surface of 5-50 nm in diameter. In particular, the nanoparticles on the abdomen and thorax of A. dorsata have an average diameter of about 10 nanometers and they are smaller than those found on wings of the same bees which are about 20 nanometers. The nanoparticles found are different of the ones previously observed on honey bees or other insects. The origin and role of these natural nanoparticles on the body of the Indian rock bee need to be to be further investigated; more research in the subject might raise important aspects in relation to the conservation of these unique pollinators.

Comparative Characterisation of CNS/Epoxy and BN/Epoxy Nanodielectrics Using Electrical Tree PD Measurements and Atomic Force Microscopy

2020 ◽  
Vol 48 ◽  
pp. 24-37
Author(s):  
Andrew M. Hank ◽  
Cuthbert Nyamupangedengu ◽  
Bridget Mutuma ◽  
Hu Li ◽  
Neil John Coville ◽  
...  
Keyword(s):  
The Body ◽  
Time To Failure ◽  
Insulation Material ◽  
Carbon Nanospheres ◽  
Mechanical Stiffness ◽  
Force Microscopy ◽  
Body Of Knowledge ◽  
Atomic Force ◽  
Electrical Tree ◽  
Evolution Characteristics

This paper contributes to the body of knowledge on the efforts to develop nanodielectrics as the next generation of insulation material. The time-to-failure under electrical tree-induced degradation of 1.09-1.35 vol.% hexagonal BN/Epoxy was found to be 3 times longer than in clean epoxy. For 0.31-0.33 vol.% CNS/Epoxy the time-to-failure was 24 times longer than the clean epoxy. The electrical treeing partial discharge behaviour in the BN/Epoxy and CNS/Epoxy showed distinct time-evolution characteristics different from those in the clean epoxy. The improved electrical tree endurance in BN/Epoxy relative to the clean epoxy can be attributed to increased mechanical stiffness. The superiority of the CNS/Epoxy as a nanodielectric is notable. The effect is suggested to be due to the electron affinity properties of the carbon nanospheres at appropriate dispersion levels.

The Natural Patterns of Self-Cleaning Surfaces: RIMAPS Analysis of Superhydrophobic Leaves

2012 ◽  
Vol 20 (1) ◽  
pp. 36-40 ◽  
Author(s):  
Eduardo A. Favret ◽  
Ana M. Molina
Keyword(s):  
Random Pattern ◽  
Plant Leaves ◽  
Lotus Effect ◽  
Force Microscopy ◽  
Atomic Force ◽  
Biological Surfaces ◽  
Self Cleaning ◽  
Random Patterns ◽  
Straight Lines ◽  
Small Hydrophobic

In the last decades, a new interdisciplinary science called biomimetics has emerged that has significantly influenced the design of certain new materials. Nature, as a source of inspiration, can give us ideas and concepts to implement new functional properties. One example is the self-cleaning property (superhydrophobicity) of certain plant leaves, better known as the Lotus Effect. This term comes from the lotus leaf (Nelumbo nucifera), the best-known self-cleaning surface in nature. On this kind of leaf, water droplets roll over the leaf surface and collect dirt and other particles from the surfaces. The superhydrophobicity of these leaves is caused, in general, by a hierarchical surface structure, built by a randomly oriented small hydrophobic wax structure on the top of convex cell papillae. The wetting condition of the solid surface is a particular property of materials and depends on both surface energy and surface topography. Many papers have been written to show how superhydrophic surfaces with periodic and random patterns can be made, but few describe and characterize biological self-cleaning surfaces. These papers usually analyze them by using optical profilers and scanning electron microscopy with specific sample preparation (for example, fixation) and in some cases atomic force microscopy. The main conclusion of those works is that binary structures (hierarchical microstructures and nanostructures) and unitary structures (basically nanostructures) are found in superhydrophobic plant leaves. However, no information regarding the general micro-nano structural pattern of biological surfaces on the x-y plane has been reported. These surfaces seem to have a random pattern in most of the cases or at least a vague arrangement of its constitutive elements whose morphologies can be represented by geometrical figures (for example, hexagonal/pentagonal polygons, circles, and straight lines).

scholarly journals Structural Insights on Fusion Mechanisms of Extracellular Vesicles with Model Plasma Membrane

2020 ◽  
Author(s):  
Fabio Perissinotto ◽  
Valeria Rondelli ◽  
Beatrice Senigagliesi ◽  
Paola Brocca ◽  
László Almásy ◽  
...  
Keyword(s):  
Lipid Bilayers ◽  
Extracellular Vesicles ◽  
Small Angle ◽  
Biochemical Characterization ◽  
The Body ◽  
Supported Lipid Bilayers ◽  
Force Microscopy ◽  
X Ray Scattering ◽  
Atomic Force ◽  
Liquid Ordered

AbstractExtracellular vesicles (EVs) represent a potent intercellular communication system. Within a lipid bilayer such small vesicles transport biomolecules between cells and throughout the body, strongly influencing the fate of recipient cells. Due to their specific biological functions they have been proposed as biomarkers for various diseases and as optimal candidates for therapeutic applications. Despite of their extreme biological relevance, the small size (30 to a few hundred nanometers in diameter) of EVs still poses a great challenge for their isolation, quantification and biophysical/biochemical characterization, therefore the complex network of EVs and cells as well as their interaction remains to be further revealed. Here we propose a multiscale platform based on Atomic Force Microscopy, Small Angle X-ray Scattering, Small Angle Neutron Scattering and Neutron Reflectometry to reveal structure-function correlations of purified EVs through the analysis of their interaction with model membrane systems, in form of both supported lipid bilayers and suspended unilamellar vesicles of variably complex composition. The analysis reveals a strong interaction of EVs with the model membranes and preferentially with liquid ordered raft-like lipid domains, and opens the way to understand uptake mechanisms in different vesicle to cell membrane relative compositions.

scholarly journals Matching the Cellulose/Silica Films Surface Properties for Design of Biomaterials That Modulate Extracellular Matrix

Membranes ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 840
Author(s):  
Adina-Maria Dobos ◽  
Elena-Laura Ursu ◽  
Luiza-Madalina Gradinaru ◽  
Marius Dobromir ◽  
Anca Filimon
Keyword(s):  
Surface Properties ◽  
Photoelectron Spectroscopy ◽  
Surface Segregation ◽  
Composite Films ◽  
Force Microscopy ◽  
Membrane Surfaces ◽  
Low Surface Energy ◽  
Atomic Force ◽  
Biological Surfaces ◽  
Physical And Chemical

The surface properties of composite films are important to know for many applications from the industrial domain to the medical domain. The physical and chemical characteristics of film/membrane surfaces are totally different from those of the bulk due to the surface segregation of the low surface energy components. Thus, the surfaces of cellulose acetate/silica composite films are analyzed in order to obtain information on the morphology, topography and wettability through atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and contact angle investigations. The studied composite films present different surface properties depending on the tetraethyl orthosilicate (TEOS) content from the casting solutions. Up to a content of 1.5 wt.% TEOS, the surface roughness and hydrophobicity increase, after which there is a decrease in these parameters. This behavior suggests that up to a critical amount of TEOS, the results are influenced by the morphology and topographical features, after which a major role seems to be played by surface chemistry—increasing the oxygenation surfaces. The morphological and chemical details and also the hydrophobicity/hydrophilicity characteristics are discussed in the attempt to design biological surfaces with optimal wettability properties and possibility of application in tissue engineering.

scholarly journals Revision of Benedeniella Johnston, 1929 (Monogenea: Capsalidae), its assignment to Entobdellinae Bychowsky, 1957 and comments on subfamilial composition

Zootaxa ◽  
2010 ◽  
Vol 2519 (1) ◽  
pp. 1 ◽  
Author(s):  
IAN D. WHITTINGTON
Keyword(s):  
United Arab Emirates ◽  
Molecular Genetic ◽  
Arabian Gulf ◽  
Ventral Surface ◽  
The Body ◽  
Cownose Ray ◽  
Molecular Genetic Data ◽  
Eastern Usa ◽  
New Material ◽  
Ventral Skin

Benedeniella macrocolpa (Lühe, 1906) Yamaguti, 1963 is redescribed from new material collected from ventral skin surfaces of the Australian cownose ray, Rhinoptera neglecta Ogilby (Elasmobranchii: Myliobatidae) from waters in Moreton Bay and from captive rays in a public display aquarium in Townsville, from R. cf. neglecta and Rhinoptera sp. from Weipa, Queensland, Australia and from R. javanica Müller & Henle caught in the Arabian Gulf north of Dubai, United Arab Emirates. Benedeniella posterocolpa (Hargis, 1955) Yamaguti, 1963 is redescribed from new specimens collected from the cownose ray, R. bonasus (Mitchill) (Myliobatidae) from several localities in the Gulf of Mexico and in the Chesapeake Bay region of the south-eastern and eastern USA, respectively. Detailed anatomical redescriptions demonstrate that each Benedeniella species share several dorsal structures (paired anterior horns, excretory papillae and posterior conical structures at the junction of the body with the haptor), anterolateral grooves on the ventral surface of each anterior attachment organ, a similar route for tendons associated mostly with the accessory sclerites and the anterior hamuli and a long vagina. The different path of the vagina and the position of the vaginal pore are the simplest characters to discriminate the two species. Benedeniella unnithani Gupta & Chanana, 1976 from the gills of a Caranx sp. (Teleostei: Perciformes: Carangidae) off Kavaratti, Laccadive Islands, Arabian Sea, India is considered a species incertae sedis. Morphological parallels are identified, in particular concerning the anterior attachment organs of species in Benedeniella, Branchobdella Kearn, Whittington & Evans-Gowing, 2007, Entobdella Blainville in Lamarck, 1818, Neoentobdella Kearn & Whittington, 2005 and Pseudoentobdella Yamaguti, 1963. Of these entobdelline genera, species in three of them parasitise principally the skin of elasmobranch rays (Dasyatidae; Myliobatidae; Rhinobatidae); only species in Branchobdella and Entobdella parasitise flatfish teleosts (Paralichthyidae; Pleuronectidae; Soleidae). On the basis of the redescriptions presented here plus morphological similarities, host associations and recently published molecular genetic data, Benedeniella is moved from the Benedeniinae Johnston, 1931 and the diagnosis for the Entobdellinae Bychowsky, 1957 is amended to unite Benedeniella, Branchobdella, Entobdella, Listrocephalos Bullard, Payne & Braswell, 2004, Neoentobdella and Pseudoentobdella. The affinities of species in a seventh capsalid genus, Trimusculotrema Whittington & Barton, 1990 (currently in Benedeniinae), are considered briefly based on morphology and host association and reassigned to the Entobdellinae.

scholarly journals Impact of Diabetes Mellitus on Human Erythrocytes: Atomic Force Microscopy and Spectral Investigations

2018 ◽  
Vol 15 (11) ◽  
pp. 2368 ◽  
Author(s):  
Mohamad S. AlSalhi ◽  
Sandhanasamy Devanesan ◽  
Khalid E. AlZahrani ◽  
Mashael AlShebly ◽  
Fatima Al-Qahtani ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Atomic Force Microscopy ◽  
Present Report ◽  
The Body ◽  
Diabetic Patients ◽  
Force Microscopy ◽  
Atomic Force ◽  
Sugar Levels

Diabetes mellitus (DM) is a common metabolic disease indicated by high sugar levels in the blood over a prolonged period. When left untreated, it can lead to long-term complications, such as cardiovascular disease, stroke, and diabetic retinopathy or foot ulcers. Approximately 415 million people (about 8.3% of the world’s population) had diabetes worldwide in 2015, with 90% of the cases classified as Type 2 DM, which is caused by insulin resistance that arises mostly from being overweight and from a lack of exercise. DM affects every part of the body, including the erythrocytes. The aim of the present report is to gain insight into the damage done to the erythrocytes of patients classified with pre-diabetes and diabetes (plenty are found in the Kingdom of Saudi Arabia, a country where young people encompass a large segment of the population). The study presents results on the morphological analysis of erythrocytes by atomic force microscopy (AFM) and molecular investigations by fluorescence spectroscopy (FS). Our results indicate significant differences (in the morphology, size, and hemolytic end products) between the erythrocytes of diabetic patients (HbA1C, glycated hemoglobin, levels of 8–10%) and normal controls. It is well-known that DM and smoking are two major contributory factors for cardiovascular diseases (CVDs), and our observations presented in this study suggest that diabetes plays a relatively less damaging role than smoking for CVD.

Application of AFM to the Nanomechanics of Cancer

MRS Advances ◽  
2016 ◽  
Vol 1 (25) ◽  
pp. 1817-1827 ◽  
Author(s):  
Shivani Sharma ◽  
James K Gimzewski
Keyword(s):  
Mechanical Properties ◽  
Cancer Detection ◽  
Cell Mechanics ◽  
Single Cells ◽  
Cellular Level ◽  
The Body ◽  
Force Microscopy ◽  
Atomic Force ◽  
Cell Metastasis ◽  
Technological Limitations

ABSTRACTCancer cell metastasis is a leading cause of mortality whereby cancer cells migrate from a tumor and spread to distant sites in the body. Understanding metastasis requires a deeper understanding of biomechanics and mechanobiology at the cellular level. We have established the use of Atomic Force Microscopy to infer the mechanical properties of single cells in cultures by measurement of their Young’s modulus. Here we discuss the main advantages, challenges, technological limitations and applicability of AFM based cell mechanics studies along with other emerging high throughput techniques for the development of single cell mechanical based clinical assays for cancer detection and management.

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