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Search for "hairs" in Full Text gives 42 result(s) in Beilstein Journal of Nanotechnology.
Natural nanofibers embedded in the seed mucilage envelope: composite hydrogels with specific adhesive and frictional properties
Beilstein J. Nanotechnol. 2024, 15, 1603–1618, doi:10.3762/bjnano.15.126
- of the adhesive properties of plant root hairs was done experimentally to give an idea about the adhesive power of the plant. Adventitious roots of Hedera helix reached a maximal adhesion (Fmax) of 7.07 N, tendrils of Parthenocissus quinquefolia (Virginia Creeper) were on the second position with
- 14.03 N, and the maximal measured value belongs to the tendrils of Campsis radicans, namely, 25.18 N [142]. The sea grass (Posidonia oceanica) root hairs can also generate strong adhesion under sea water conditions [143][144][145]. Attachment pads or roots are special organs organised in clusters and
Green synthesis of silver nanoparticles derived from algae and their larvicidal properties to control Aedes aegypti
Beilstein J. Nanotechnol. 2024, 15, 1566–1575, doi:10.3762/bjnano.15.123
- eating habits. For both pathways, damage to the midgut, epithelial cells, and cortex in mosquito larvae can be observed, resulting in physiological changes such as shrinkage in the abdominal region, change in the shape of the thorax and loss of lateral hairs, oral brushes, and anal gills. These processes
Polymer lipid hybrid nanoparticles for phytochemical delivery: challenges, progress, and future prospects
Beilstein J. Nanotechnol. 2024, 15, 1473–1497, doi:10.3762/bjnano.15.118
- testosterone-induced alopecia suggested that QCT-PLHNPs exhibited significantly higher regrowth of hairs than free QCT. Yin and co-workers developed QCT-encapsulated cholate-modified PLHNPs (QCT-cPLHNPs) to achieve better therapeutic efficacy against leukemia [92]. Cell culture studies suggested that the QCT
Hymenoptera and biomimetic surfaces: insights and innovations
Beilstein J. Nanotechnol. 2024, 15, 1333–1352, doi:10.3762/bjnano.15.107
- to a reduction in electronic waste, as devices retain their visual appeal over a longer period. The techniques to create biomimetic materials with color producing mechanisms inspired by insects already exist [29][30] and applications of such technology have several possibilities. Hairs The body
- surface of insects is equipped with hairs (sensu lato) with different morphologies. These structures may first be categorized into two main types, that is, setae, which have a socket (which originates from an adjacent cell) and microtrichia (not socked and thus originating from one cell) [39][40]. Such
- example, through trichoid sensilla on the compound eyes of honeybees [45], which are important to maintain and coordinate flight. In general, the head capsule of Hymenoptera is densely covered with hairs and may be a ground-plan feature of Hymenoptera and a potential autapomorphy [46]. While the reason
Functional morphology of cleaning devices in the damselfly Ischnura elegans (Odonata, Coenagrionidae)
Beilstein J. Nanotechnol. 2024, 15, 1260–1272, doi:10.3762/bjnano.15.102
- in a hard base of sclerotized chitin, and ends in a soft tip, either rich in resilin or of unsclerotized chitin. A material gradient from stiff bases to soft tips has also been found in the adhesive hairs of insect leg attachment systems [38][39][54]. This gradient prevents the clustering of adhesive
- hairs, while the soft tips ensure effective contact between the attachment system and the substrate. Similarly, the material gradient in grooming devices may enhance adhesion to foreign materials for grooming body surfaces. The soft tip and soft lateral cuticular lamina adapt to various surface
Beyond biomimicry – next generation applications of bioinspired adhesives from microfluidics to composites
Beilstein J. Nanotechnol. 2024, 15, 965–976, doi:10.3762/bjnano.15.79
- vacuum triggering) or locally (using positive pressure in geckofluidic channels) are also feasible. The utility of multiheight fibers, understood back in 2008 based on personal observations of spider foot hairs’ adhesion mechanisms, is that a biomimetic adhesive can remain in a default non-adhesive state
Functional fibrillar interfaces: Biological hair as inspiration across scales
Beilstein J. Nanotechnol. 2024, 15, 664–677, doi:10.3762/bjnano.15.55
- , reversible adhesion, and surface modulation (e.g., superhydrophobicity). This review will present various functions that biological hairs have been discovered to carry out, with the hairs spanning across six orders of magnitude in size, from the millimeter-thick fur of mammals down to the nanometer-thick
- fibrillar ultrastructures on bateriophages. The hairs are categorized according to their functions, including protection (e.g., thermal regulation and defense), locomotion, feeding, and sensing. By understanding the versatile functions of biological hairs, bio-inspired solutions may be developed across
- form of collagen [1] and microtubules and microfilaments [2], and externally in the form of silk [3] and hair [4][5]. Among these prevalent, quasi-one-dimensional structures, here we loosely define biological “hairs” as high-aspect-ratio structures that are external and passive. This definition is
Suspension feeding in Copepoda (Crustacea) – a numerical model of setae acting in concert
Beilstein J. Nanotechnol. 2023, 14, 603–615, doi:10.3762/bjnano.14.50
- these tips are also rather soft and flexible, similar to attachment hairs in insects showing high adhesion at the tips [58]; for in-depth reviews, see [59][60][61]. In contrast, the tips of the long setae did not emit blue signals. The simulation presented here takes into account the actual physical
Straight roads into nowhere – obvious and not-so-obvious biological models for ferrophobic surfaces
Beilstein J. Nanotechnol. 2022, 13, 1345–1360, doi:10.3762/bjnano.13.111
- “staying dry under water” for a much longer time [4][5]. Such surfaces usually feature functional structures that are larger than the wax crystals on the Lotus leaf (or other superhydrophobic leaf surfaces showing specially structured wax covers). Many of these surfaces possess hairs, such as those of the
- ) and the skin structure of springtails (Collembola, see Figure 3) [3][21][22], both of which are known to accommodate gas layers. Kariba weed (Salvinia molesta) In the case of Salvinia molesta, stable water/air interfaces form at the tips of leaf hairs, which are topped by eggbeater-like structures
- air layer between ship hull and water reduces the drag considerably. The physical basis of the capability of the Salvinia hairs to hold persistent air layers was the topic of various studies [5][26], which also included their elastic properties [27][28]. Main factors for the persistence and resilience
Roll-to-roll fabrication of superhydrophobic pads covered with nanofur for the efficient clean-up of oil spills
Beilstein J. Nanotechnol. 2022, 13, 1228–1239, doi:10.3762/bjnano.13.102
- slightly thinner (a few tens of micrometers) than the nominal material thickness. In this way, the laminated films experience only minimal embossing forces during their pass through the calender and the rough sandblasted surface of the heated roller pulls tiny polymer hairs out of the melted surface of the
- contact angle measurements, especially on hydrophobic surfaces, can further distort the measured values [30]. The quality of the nanofur in terms of its hydrophobicity and oil absorption quantity depends on several processing factors including length of the hairs, their density, and their overall
- the nominal thickness to compensate thickness variations in the processed film and to structure the film more uniformly. If the gap size is set just at or slightly above the nominal thickness, only the thickest parts of the film are structured. If the gap is too small, no hairs are pulled out of the
Interaction between honeybee mandibles and propolis
Beilstein J. Nanotechnol. 2022, 13, 958–974, doi:10.3762/bjnano.13.84
- end (Figure 2B). The medial surface of this tip was examined more extensively because it is used by bees to process and form propolis (Figure 4A). The spoon-shaped tip tapers towards the distal apex. On one side it exhibits an edge densely covered by smooth, long, and flexible hairs (hairy edge
- ), reaching over half of the mandible medial surface (Figure 4A,G), while the edge on the opposite site is sharp and hairless (sharp edge). Though, short, thin hairs grow on the mandible outside close to the sharp edge. A ridge runs along the centre of the medial surface of the mandible tip (central ridge
- the same height as the bristles and hairs. The outside of the mandible is covered with hairs evenly. Surface structures on bee mandibles SEM micrographs also revealed that bee mandibles are covered with anisotropic scale-like micropatterns (Figure 4). Most of the scales on the medial surface of the
Fabrication and testing of polymer microneedles for transdermal drug delivery
Beilstein J. Nanotechnol. 2022, 13, 629–640, doi:10.3762/bjnano.13.55
- , using experimental procedures approved by the University of Southern Queensland (USQ) and the University of Queensland (UQ) animal ethics and biosafety committees. The skins were shaved to remove the excess hairs and kept frozen at −20 °C on a flat aluminum surface, then sectioned using a surgical knife
Design and characterization of polymeric microneedles containing extracts of Brazilian green propolis
Beilstein J. Nanotechnol. 2022, 13, 503–516, doi:10.3762/bjnano.13.42
- temperature to be used in further tests. The porcine skin samples were obtained by dissection of skins from the ears of pigs (albinos and youngsters), which were recently slaughtered. The skin patches were washed, the hairs cut and, later, the patches were dissected in order to extract the epidermis and
Physical constraints lead to parallel evolution of micro- and nanostructures of animal adhesive pads: a review
Beilstein J. Nanotechnol. 2021, 12, 725–743, doi:10.3762/bjnano.12.57
- secondarily reduced in Zoraptera [59], several other groups include hairy structures. Adhesive hairs not only independently evolved in Dermaptera [96], Plecoptera [179], Phasmatodea [108][109], Dictyoptera [154], and Mantophasmatodea [2][59], but also reveal different stages of reversals or repetitive origins
- under compression but strong under tension, (4) anisotropy in fibre orientation, and (5) presence of fluid in the contact area. Adaptation to fractal substrate surfaces due to hierarchical organization Hairs with high aspect ratios in the hairy systems and internal fibres/filaments of smooth systems
- , reduced due to the reduced ability to form a close contact with rough substrata. Surface pattern and contact splitting The function of hairs/setae in hairy pads is partially discussed in the previous paragraphs. Comparative studies on different animal groups comprising hairy attachment pads reveal
A comparison of tarsal morphology and traction force in the two burying beetles Nicrophorus nepalensis and Nicrophorus vespilloides (Coleoptera, Silphidae)
Beilstein J. Nanotechnol. 2019, 10, 47–61, doi:10.3762/bjnano.10.5
- , Hauptstr.1, 79104 Freiburg, Germany 10.3762/bjnano.10.5 Abstract Our aim was to compare friction and traction forces between two burying beetle species of the genus Nicrophorus exhibiting different attachment abilities during climbing. Specifically, the interaction of adhesive hairs and claws during
- traction force measurements of entire animals, whereas the performance of single fore tarsi has been measured with a nanotribometer. Both the number and the special morphology of the tarsal tenent hairs of the fore, middle and hind tarsi have been investigated by scanning electron microscopy (SEM). The
- hairs. The precise way in which the viscosity of the adhesion-mediating tarsal secretion of insects influences friction performance remains the subject of debate. Nevertheless, subtle differences in the hydrocarbon profiles of the tarsal secretion, probably leading to a decreased fluidity in N
Bidirectional biomimetic flow sensing with antiparallel and curved artificial hair sensors
Beilstein J. Nanotechnol. 2019, 10, 32–46, doi:10.3762/bjnano.10.4
- sensory hairs found on crickets. To distinguish between rotation and translation normal to the substrate, two electrodes on a membrane were attached to the base of the pillar. The capacitive read-out indicates the movement of the pillar. High-density arrays were designed to increase the total capacitance
A new bioinspired method for pressure and flow sensing based on the underwater air-retaining surface of the backswimmer Notonecta
Beilstein J. Nanotechnol. 2018, 9, 3039–3047, doi:10.3762/bjnano.9.282
- backswimmers (Notonecta sp.) are well known for their ability to retain air layers on the surface of their forewings (hemelytra). While analyzing the hemelytra of Notonecta, we found that the air layer on the hemelytra, in combination with various types of mechanosensitive hairs (clubs and pins), most likely
The effect of flexible joint-like elements on the adhesive performance of nature-inspired bent mushroom-like fibers
Beilstein J. Nanotechnol. 2018, 9, 2893–2905, doi:10.3762/bjnano.9.268
- microscopy (CLSM) of a lateral view of discoidal (mushroom-shaped) adhesive hairs in a male ladybird beetle. Differences in the autofluorescence indicate the presence and distribution of different materials. Blue regions (transitions from the hair shaft to the tip structure) indicate portions of the soft
- , rubber-like protein resilin. Light blue regions (hair shaft and discoidal tip structure) mainly consist of stiffer chitinous material. Adapted from [32]. b) Scanning electron microscope (SEM) images of synthetic, polymeric, bent fibers inspired by the adhesive hairs of the beetle, showing joints between
Tuning adhesion forces between functionalized gold colloidal nanoparticles and silicon AFM tips: role of ligands and capillary forces
Beilstein J. Nanotechnol. 2018, 9, 660–670, doi:10.3762/bjnano.9.61
- violin bow hairs observed at nanoscale by AFM, may cause strong consequences at mascoscopic scale during the stick–slip phenomenon of the rubbing hairs surfaces and in fine such different acoustic outputs. Therefore, control of the nanoscale interactions between two surfaces through chemistry and contact
Dry adhesives from carbon nanofibers grown in an open ethanol flame
Beilstein J. Nanotechnol. 2017, 8, 2719–2728, doi:10.3762/bjnano.8.271
- properties [10][11][12][13][14][15][16][17][18]. This utilization is inspired by geckos, which have very impressive adhesion properties, originating from thousands of hierarchically arranged hairs covering their toes. The smallest hairs with a tip diameter of about 200 nm efficiently get in contact with
- GPa [30]. CNTs act similarly to the hairs of a Gecko, due to their diameters in the nanometer-range, they can bend quite easily when getting in contact with a rough surface. This effect enables effective contact splitting [31], which leads to an increased contact area, resulting in a high adhesion
Surfactant-induced enhancement of droplet adhesion in superhydrophobic soybean (Glycine max L.) leaves
Beilstein J. Nanotechnol. 2017, 8, 2345–2356, doi:10.3762/bjnano.8.234
- hairs on the leaves. Agnique® SBO10 and the nonionic surfactant XP ED 75 increased the droplet adhesion and caused an increase of the TA from 20.9° to 85° and 90°, respectively. Scanning electron microscopy showed that surfactants with a hydrophilic–lipophilic balance value below 10 caused a size
- solubilization of the waxes and gas chromatography (GC–FID) and mass spectroscopy (GC–MS). Results Micromorphology of the leaf surface The micromorphology of leaf surfaces was investigated by scanning electron microscopy (SEM) and 3D light microscopy. Trichomes, commonly termed hairs, are slightly tilted, up to
- 2 mm in length, and are evenly distributed over the upper (adaxial) (Figure 1A,B) as well as the lower (abaxial) leaf sides. In contrast to the epidermal cells, the hairs were not covered with wax crystals. The epidermis cells are polygonal with undulated anticlinal cell boundaries (Figure 1C). The
Air–water interface of submerged superhydrophobic surfaces imaged by atomic force microscopy
Beilstein J. Nanotechnol. 2017, 8, 1671–1679, doi:10.3762/bjnano.8.167
- Notonecta (Figure 1c,d) with its double structure of longer hairs and a dense “carpet” of so-called microvilli. Based on the analysis of hundreds of aquatic and semiaquatic species, four criteria for the maintenance of persistent air layers underwater have been identified [3]. The structures on these
- the total internal reflection of light at the air–water interface. d) The backswimmers double structure of longer hairs (grey and yellow) and a dense “carpet” of smaller hairs (microvilli, green) is responsible for the long-term air-retention capability. Representation of the measurement of the air
Studying friction while playing the violin: exploring the stick–slip phenomenon
Beilstein J. Nanotechnol. 2017, 8, 159–166, doi:10.3762/bjnano.8.16
- the stick–slip effect at the mesoscale. Two violin bow hairs were studied, a natural horse tail used in a professional philharmonic orchestra, and a synthetic one used with a violin for beginners. Atomic force microscopy characterization revealed clear differences when comparing the surfaces of both
- bow hairs, suggesting that a structure having peaks and a roughness similar to that of the string to which both bow hairs rubbed permits a better control of the stick–slip phenomenon. Keywords: atomic force microscopy; bow hair; friction; stick–slip; tribology; violin; Introduction Friction is
- dependence), bow position, tilt, inclination, and bow force [9][10][11] (see Figure 1). Therefore, if these parameters are fixed, we can use the resulting sound of a bow-stringed musical instrument as a signal to measure characteristics of the mesoscale friction between the bow hairs and the strings. However
When the going gets rough – studying the effect of surface roughness on the adhesive abilities of tree frogs
Beilstein J. Nanotechnol. 2016, 7, 2116–2131, doi:10.3762/bjnano.7.201
- particle size is big enough for the tip of the hair (often a spatula) to make full contact, adhesion and friction forces are similar to those on smooth surfaces. Only when the spatula size is larger than the particle size do the forces decline. For instance, the setal hairs of geckos are built so that they
- in spiders yielded a similar result, with their adhesive hairs performing poorly when asperity sizes were between 300 nm and 1 µm [37]. The attachment of smooth adhesive pads is more complex. From our data, there is evidence of enhanced adhesion and friction when the wavelength of the surface is
From iron coordination compounds to metal oxide nanoparticles
Beilstein J. Nanotechnol. 2016, 7, 2074–2087, doi:10.3762/bjnano.7.198
- structures protruding from the surface at various angles, but generally in a radial direction from the sphere center. The diameter of the spheres is 80 ± 60 nm, and the hairs are of 20 ± 5 nm length and 2 ± 0.5 nm width. The analysis of the samples by IR spectroscopy (Supporting Information File 1, Figure S6
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