Fig 2 - uploaded by R. Ritter
Content may be subject to copyright.
![TEM image of Euglena terricola showing the pellicle strips in cross-section (arrows). The arrowhead points toward a pellicle pore, where the biogenic lubricant, the mucus (M), is excreted. Image reproduced with permission from [5]. © 2000 by the Society of Protozoologists.](profile/R-Ritter/publication/200015406/figure/fig1/AS:394124214718464@1470977943976/TEM-image-of-Euglena-terricola-showing-the-pellicle-strips-in-cross-section-arrows-The.png)
TEM image of Euglena terricola showing the pellicle strips in cross-section (arrows). The arrowhead points toward a pellicle pore, where the biogenic lubricant, the mucus (M), is excreted. Image reproduced with permission from [5]. © 2000 by the Society of Protozoologists.
Source publication
Matter produced by organisms is remarkable. Evolutionary optimized properties, e.g. regarding hydrodynamic, aerodynamic, wetting and adhesive behavior, can already be found in the “simplest” forms of organisms. Euglena gracilis, a single-celled algal species, performs tasks as diverse as sensing the environment and reacting to it, converting and st...
Contexts in source publication
Context 1
... striated pellicle covering the whole cell is a distinct exoskeletal feature of the Euglena species [3-6, Fig. 2]. The pellicle is a proteinaceous structure that provides mechanical stability to the cell, yet it is flexible. Its single strips are connected via interlocking ridges that can slide against each other and are lubricated via biogenic lubricants excreted from pellicle pores (Fig. 2). These features and the concepts they are based on ...
Context 2
... cell is a distinct exoskeletal feature of the Euglena species [3-6, Fig. 2]. The pellicle is a proteinaceous structure that provides mechanical stability to the cell, yet it is flexible. Its single strips are connected via interlocking ridges that can slide against each other and are lubricated via biogenic lubricants excreted from pellicle pores (Fig. 2). These features and the concepts they are based on stimulated our interest in the Euglena gracilis organism. There are already many TEM and SEM as well as optical microscopy images available of this algal species, but only sparsely atomic force microscopy (AFM) data [7]. [8]. Reproduced with permission from [8]. © 1967 Englewood ...
Similar publications
Dynamic force microscopy (DFM) is an excellent tool for the study of the compositional and nanomechanical properties of polymers that exploits the flexural eigenmodes of a cantilever comprising a sharp tip vibrating perpendicular to the sample surface. However, the in-plane nanomechanical properties of a specimen cannot be detected by this techniqu...
A fundamental understanding of biofilm mechanical stability is critical in order to describe detachment and develop biofouling control strategies. It is thus important to characterise the elastic deformation and flow behaviour of the biofilm under different modes of applied force. In this study, the mechanical properties of a mature wastewater biof...
Significance
The hydration water layer (HWL) is a ubiquitous form of nanoscale water bound to the hydrophilic surfaces and plays a critical role in diverse phenomena in nature. Especially, investigation of its nonlinear fluidic properties is important for better understanding of its rheological contributions at a microscopic level. Using precise co...
Citations
... It is not yet clear how the E. Gracilis mechanically initiates each turn, but there are three possibilities: (1) bending its body in the direction of the turn (Figs. 8(a), 8(c) and 8(d)), (2) using the flagellum in a complex stroke or (3) a combination of these two. It was suggested that uni-flagellate bacteria with posterior-attached flagella ("fluid pushers") exploit a buckling instability of the hook to change direction during forward swimming [21] . ...
The hydrodynamics and locomotion mechanism of Euglena Gracilis (E. Gracilis) is investigated using microscopic shadow imaging and micro particle image velocimetry (MicroPIV). Three distinct locomotion modes were observed: translation, spin, and left/right turn. Since the flagellum was not possible to image, the strokes were identified by evaluating the flow field around the protist. The flow field information is obtained using a phase-separated PIV evaluation, which uses a histogram-thresholding based dynamic masking approach. The temporal resolution of the experiment was sufficient to identify the sequence of two modes, translation and spin, and the stroke-pulling frequency. The flow field result during a stroke is compared with existing Stokeslet dipole theories and flow disturbance decay with distance is investigated. The results indicate that the organism has a complex locomotion technique that allows the change of direction, axial orientation and propulsion.
... A commercial stainless steel disks with a diameter of 20 mm and thickness of 5 mm and posses of the following composition (wt. %): C, 0.7; P, 0.03; S, 0.05; Mn, 1. 38 ZrO 2 -7wt.%Y 2 O 3 (Nanox S4007, Inframat) was deposited on stainless steel substrate using Praxair 100-kW, standard SG100 plasma torch (Praxair, USA.) atmospheric plasma spraying system. Fig. 1 shows the plasma spraying system layout. ...
Thermal barrier coatings (TBCs) have been widely used to reduce the temperature imposed on hot section of the metallic components (vanes, blades, shrouds) which are subjected to high temperature such as gas turbines and diesel engines. Zirconia is used as thermal barrier coating due it low thermal conductivity, high melting point, excellent thermal shock resistance, high resistance to oxidation and high hardness. In this work, the nanostructured yittria stabilized zicronia (YSZ) powders were deposited on stainless steel substrates using atmospheric plasma spray system. The steel substrates were plasma-sprayed with three different plasma powers while the other significant parameters such plasma gas pressure, powder flow rate, standing distance, and spray speed were kept constant. Each sample was then subjected to tribological test using pin-on-disc CSEM Tribometer, hardness test and surface roughness measurement. Scanning electron microscope is used to observe the morphology of the nanostructured coatings and wear track after tribological tests. Based of the test results, the following phenomena on the plasma-sprayed nanostructured YSZ coating could be concluded; (i) lower friction coefficient, (ii) higher wear resistance, (iii) higher hardness, (iv) smoother surface. It is shown that the optimum mechanical and tribological characteristics were obtained under the plasma power of 32kW.
Arsenic (As) is a serious pollutant of water bodies. Its presence in water can cause severe health problems in humans and may also induce serious toxicological effects in aquatic organisms. Euglena gracilis, a unicellular freshwater flagellate, is considered very sensitive to environmental pollutants. The aim of the present study was to evaluate the responses of different parameters in E. gracilis toward arsenite (As-III) toxicity and to assess As-III removal potential of E. gracilis from water by calculating bio-concentration factor (BCF). Under the optimized experimental conditions (0.1 to 10 mg L−1 of As-III, (pH 6.8) 7-day exposure), various parameters of E. gracilis like cell growth, motility, cell velocity (speed), cell shape, gravitactic orientation, biochemical parameters, and oxidative-stress markers were measured as endpoints. The experimental results showed that cell growth and photosynthetic pigments (chlorophyll a, b, and total carotenoids) were significantly affected at higher concentrations of As-III, while slight stimulation was observed in motility, orientation, and cell compactness of E. gracilis. Similarly, an increase was observed in total soluble protein and sugar content which can be regarded as a protective strategy in response of As-III stress. The adverse effects of As-III in E. gracilis can be attributed to oxidative stress as revealed by the results for oxidative markers. E. gracilis removed 13.3% of As-III from the medium with a calculated 0.27 mg As-III g−1 DW of E. gracilis. The calculated BCF, an index of the potential of accumulating metal/metalloids, in this study was 27 showing E. gracilis as accumulator but not hyper-accumulator of As-III. It is concluded that cell growth and photosynthetic pigments in E. gracilis were adversely affected by As-III and can be used as indicators of the adverse effects of As-III to aquatic autotrophs. E. gracilis can be recommended as accumulator (but not hyper-accumulator) for removal of As-III from water.
The locomotion mechanism of Euglena Gracilis is investigated using microscopic shadow imaging and Micro Particle Image Velocimetry (µPIV). Three distinct locomotion modes were observed; translation, spin and left/right turn. Since the flagellum was not possible to image, the strokes were identified by evaluating the flow field around the protist. The flow field information is obtained using a phase-separated PIV evaluation, which uses of a histogram-thresholding based dynamic masking approach. The temporal resolution of the experiment was sufficient to identify the sequence of translation and spin, and the stroke-pulling frequency. The results indicate that the organism has a complex locomotion technique that allows the change of direction, change of axial orientation and propulsion.
Biomimetics is a field that has the potential to drive major technical advances. It might substantially support successful mastering of current tribological challenges, i.e., friction, adhesion and wear in machines and devices from the meter to the nanometer scale. Science currently goes through a major change, with biology gaining increasing importance. Indeed, biology is becoming the new Leitwissenschaft. Tribology is omnipresent in biology. Various examples for biological tribosystems across dimensions are introduced to the reader, exemplifying the hierarchical nature of biomaterials, and concepts such as integration instead of additive construction, optimization of the whole instead of maximization of a single component feature, multi-functionality instead of mono-functionality and development via trial-and-error processes. The current state of biomimetics in tribology is reviewed, and possible biomimetic scenarios to overcome current tribological challenges are suggested (switchable adhesives, micromechanic devices, novel lubricants and adhesives).
A novel way to describe the complexity of biological and engineering approaches depending on the number of different base materials is proposed: Either many materials are used (material dominates) or few materials (form dominates) or just one material (structure dominates).
The complexity of the approach (in biology as well as in engineering) increases with decreasing number of base materials. Biomimetics, i.e., technology transfer from biology to engineering, is especially promising in MEMS development because of the material constraints in both fields. The
Biomimicry Innovation Method is applied here for the first time to identify naturally nanostructured rigid functional materials, and subsequently analyse their prospect in terms of inspiring MEMS development.
Biological processes, structures, functions and materials provide powerful inspiration for novel approaches in architecture. In this chapter, a variety of biological systems are introduced: Bacillus subtilis, the green alga Euglena gracilis, diatoms and red blood cells. Subsequently results of bionanotechnological research performed (by physicists) on these systems are presented. In the next step, the systems and the results are discussed with an architect, resulting in a multitude of ideas, possible approaches, experiments and projects. Such interdisciplinary access corroborates the power of collaboration across established fields in modern science and technology.
