A novel flight style allowing the smallest featherwing beetles to excel

Flight speed generally correlates positively with animal body size [1]. Surprisingly, miniature featherwing beetles can fly at speeds and accelerations of insects three times as large [2]. We show here that this performance results from a previously unknown type of wing motion. Our experiment combines three-dimensional reconstructions of morphology and kinematics in one of the smallest insects, Paratuposa placentis (body length 395 μm). The flapping bristled wing follows a pronounced figure-eight loop that consists of subperpendicular up and down strokes followed by claps at stroke reversals, above and below the body. Computational analyses suggest a functional decomposition of the flapping cycle in two power half strokes producing a large upward force and two down-dragging recovery half strokes. In contrast to heavier membranous wings, the motion of bristled wings of the same size requires little inertial power. Muscle mechanical power requirements thus remain positive throughout the wing beat cycle, making elastic energy storage obsolete. This novel flight style evolved during miniaturization may compensate for costs associated with air viscosity and helps explain how extremely small insects preserved superb aerial performance during miniaturization. Incorporating this flight style in artificial flappers is a challenge for designers of micro aerial vehicles.

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The wing beat of Drosophila Melanogaster . I. Kinematics

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1990.0040 ◽

1990 ◽

Vol 327 (1238) ◽

pp. 1-18 ◽

Cited By ~ 43

Keyword(s):

Drosophila Melanogaster ◽

Special Interest ◽

Motion Pictures ◽

Three Dimensional ◽

Slow Motion ◽

Published Data ◽

Wing Beat ◽

Three Dimensional Reconstruction ◽

Wing Motion ◽

Dimensional Reconstruction

The wing beat of small insects attracts special interest because conventional aerodynamics predict a reduction of flight efficiency when aerofoils are small and slow. The kinematics of the wing beat of tethered flying Drosophila melanogaster were investigated by using artificial slow motion pictures which were generated by single strobe flashes triggered in synchrony with the wing beat. The properties of Drosophila wing motion are described qualitatively and compared with the published data for other dipteran insects. Drosophila moves its wings in a pattern that differs considerably from the well-documented wing beat of the bigger blowfly Phormia . By means of a computerized three-dimensional reconstruction, the variables of the wing-beat cycle, such as wing path and angles of attack, are analysed quantitatively. These data will be the basis of aerodynamic calculations presented in accompanying papers.

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Taxonomy of the archosaur Ornithosuchus: reassessing Ornithosuchus woodwardi Newton, 1894 and Dasygnathoides longidens (Huxley 1877)

Earth and Environmental Science Transactions of the Royal Society of Edinburgh ◽

10.1017/s1755691016000104 ◽

2015 ◽

Vol 106 (3) ◽

pp. 199-205 ◽

Cited By ~ 5

Author(s):

M. Belén von Baczko ◽

Martín D. Ezcurra

Keyword(s):

Body Size ◽

Fossil Record ◽

Size Range ◽

Three Dimensional ◽

The Body ◽

Late Triassic ◽

Current Status ◽

Valid Species ◽

Diagnostic Features ◽

Sandstone Formation

ABSTRACTThe pseudosuchian archosaur Ornithosuchus, from the Lossiemouth Sandstone Formation (Late Triassic), Scotland, was the first ornithosuchid to be discovered, and the only one recorded, in the northern hemisphere. The fossil record of “Ornithosuchus longidens” is mainly based on natural moulds and, in a few cases, three-dimensional bony elements, complicating the interpretation of its anatomy. The taxonomy of this species has changed several times since the late 1800s and here we revisit its current status. The synonymy of “Dasygnathoides longidens” and Ornithosuchus woodwardi proposed by Walker (1964) is rejected, based on new interpretations of the holotype and referred specimens of “Dasygnathoides longidens”. The latter species is considered as a nomen dubium, because it lacks diagnostic features and cannot be identified beyond Pseudosuchia. As a result, Ornithosuchus woodwardi is resurrected as a valid species and its diagnosis is emended. The body size range of Ornithosuchus woodwardi is reduced to about a half, because ELGNM 1, previously considered the largest specimen of the genus, can no longer be referred to it. “Dasygnathoides longidens” cannot be assigned to any of the known archosauriforms from the Lossiemouth Sandstone Formation, but it still represents the largest predator currently known for its fauna.

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Biomechanics of Flight in Neotropical Butterflies: Aerodynamics and Mechanical Power Requirements

Journal of Experimental Biology ◽

10.1242/jeb.159.1.335 ◽

1991 ◽

Vol 159 (1) ◽

pp. 335-357 ◽

Cited By ~ 4

Author(s):

ROBERT DUDLEY

Keyword(s):

Energy Storage ◽

Elastic Energy ◽

Center Of Mass ◽

The Body ◽

Mechanical Power ◽

Morphological Data ◽

Vertical Force ◽

Forward Flight ◽

Insect Wings ◽

Inertial Energy

A quasi-steady aerodynamic analysis of forward flight was performed on 15 species of neotropical butterflies for which kinematic and morphological data were available. Mean lift coefficients required for flight typically exceeded maximum values obtained on insect wings under conditions of steady flow, thereby implicating unsteady aerodynamic mechanisms even during fast forward flight of some butterflies. The downstroke produced vertical forces on average 18% in excess of those necessary to support the body weight through the wingbeat, while the upstroke contributed minimal or negative vertical force. Estimated effective angles of incidence (αT of the wings averaged 39° during the downstroke and −22° during the upstroke; spanwise variation in αT was greater than the average difference between half-strokes. Total mechanical power requirements of forward flight averaged 12.5 W kg−1, for the case of perfect elastic storage of whig inertial energy, and 20.2 W kg−1, assuming zero elastic energy storage. Energetic costs of the erratic trajectories during forward flight increased mechanical power requirements by an average of 43%, assuming perfect elastic storage. Fluctuations in horizontal kinetic energy of the center of mass were principally responsible for this dramatic increase. When comparing different species, total mechanical power increased linearly with forward airspeed (assuming perfect elastic energy storage of inertial energy) and scaled with mass0.26 If no elastic energy storage was assumed, mechanical power was independent of airspeed and was proportional to mass0.36. Estimated metabolic rates during flight averaged 22 and 36 ml O2 g−1 h−1, for the cases of perfect and zero elastic storage, respectively. Note: Mailing address: Smithsonian Tropical Research Institute, APO Miami, FL 34002, USA.

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Comparison of 3D laser-based photonic scans and manual anthropometric measurements of body size and shape in a validation study of 123 young Swiss men

PeerJ ◽

10.7717/peerj.2980 ◽

2017 ◽

Vol 5 ◽

pp. e2980 ◽

Cited By ~ 13

Author(s):

Nikola Koepke ◽

Marcel Zwahlen ◽

Jonathan C. Wells ◽

Nicole Bender ◽

Maciej Henneberg ◽

...

Keyword(s):

Body Size ◽

Body Shape ◽

Measurement Techniques ◽

Three Dimensional ◽

Reliability And Validity ◽

Repeated Measurements ◽

The Body ◽

Anthropometric Measurements ◽

Risk Category ◽

Shape Indices

BackgroundManual anthropometric measurements are time-consuming and challenging to perform within acceptable intra- and inter-individual error margins in large studies. Three-dimensional (3D) laser body scanners provide a fast and precise alternative: within a few seconds the system produces a 3D image of the body topography and calculates some 150 standardised body size measurements.ObjectiveThe aim was to enhance the small number of existing validation studies and compare scan and manual techniques based on five selected measurements. We assessed the agreement between two repeated measurements within the two methods, analysed the direct agreement between the two methods, and explored the differences between the techniques when used in regressions assessing the effect of health related determinants on body shape indices.MethodsWe performed two repeated body scans on 123 volunteering young men using a Vitus Smart XXL body scanner. We manually measured height, waist, hip, buttock, and chest circumferences twice for each participant according to the WHO guidelines. The participants also filled in a basic questionnaire.ResultsMean differences between the two scan measurements were smaller than between the two manual measurements, and precision as well as intra-class correlation coefficients were higher. Both techniques were strongly correlated. When comparing means between both techniques we found significant differences: Height was systematically shorter by 2.1 cm, whereas waist, hip and bust circumference measurements were larger in the scans by 1.17–4.37 cm. In consequence, body shape indices also became larger and the prevalence of overweight was greater when calculated from the scans. Between 4.1% and 7.3% of the probands changed risk category from normal to overweight when classified based on the scans. However, when employing regression analyses the two measurement techniques resulted in very similar coefficients, confidence intervals, andp-values.ConclusionFor performing a large number of measurements in a large group of probands in a short time, body scans generally showed good feasibility, reliability, and validity in comparison to manual measurements. The systematic differences between the methods may result from their technical nature (contact vs. non-contact).

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Triassic pentadactyl tracks from the Los Menucos Group (Río Negro province, Patagonia Argentina): possible constraints on the autopodial posture of Gondwanan trackmakers

PeerJ ◽

10.7717/peerj.5358 ◽

2018 ◽

Vol 6 ◽

pp. e5358 ◽

Cited By ~ 9

Author(s):

Paolo Citton ◽

Ignacio Díaz-Martínez ◽

Silvina de Valais ◽

Carlos Cónsole-Gonella

Keyword(s):

Body Weight ◽

Body Size ◽

Soft Tissues ◽

Weight Bearing ◽

Three Dimensional ◽

Upper Triassic ◽

Point Of View ◽

The Body ◽

Late Triassic ◽

Karoo Basin

The Los Menucos locality in Patagonia, Argentina, bears a well-known ichnofauna mostly documented by small therapsid footprints. Within this ichnofauna, large pentadactyl footprints are also represented but to date were relatively underinvestigated. These footprints are here analyzed and discussed based on palaeobiological indications (i.e., trackmaker identification). High resolution digital photogrammetry method was performed to achieve a more objective representation of footprint three-dimensional morphologies. The footprints under study are compared withPentasauropusfrom the Upper Triassic lower Elliot Formation (Stormberg Group) of the Karoo Basin (Lesotho, southern Africa). Some track features suggest a therapsid-grade synapsid as the potential trackmaker, to be sought among anomodont dicynodonts (probably Kannemeyeriiformes). While the interpretation of limb posture in the producer ofPentasauropustracks from the Los Menucos locality agrees with those described from the dicynodont body fossil record, the autopodial posture does not completely agree. The relative distance between the impression of the digital (ungual) bases and the distal edge of the pad trace characterizing the studied tracks likely indicates a subunguligrade foot posture (i.e., standing on the last and penultimate phalanges) in static stance, but plantiportal (i.e., the whole foot skeleton and related soft tissues are weight-bearing) during the dynamics of locomotion. The reconstructed posture might have implied an arched configuration of the articulated metapodials and at least of the proximal phalanges, as well as little movement capabilities of the metapodials. Usually, a subunguligrade-plantiportal autopod has been described for gigantic animals (over six hundreds kilograms of body weight) to obtain an efficient management of body weight. Nevertheless, this kind of autopod is described here for large but not gigantic animals, as the putative trackmakers ofPentasauropuswere. This attribution implies that such an autopodial structure was promoted independently from the body size in the putative trackmakers. From an evolutionary point of view, subunguligrade-plantiportal autopods not necessarily must be related with an increase in body size, but rather the increase in body size requires a subunguligrade or unguligrade, plantiportal foot. Chronostratigraphically,Pentasauropuswas reported from Upper Triassic deposits of South Africa and United States, and from late Middle Triassic and Upper Triassic deposits of Argentina. Based on the stratigraphic distribution of the ichnogenus currently accepted, a Late Triassic age is here proposed for thePentasauropus-bearing levels of the Los Menucos Group.

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The relationship between mechanical work and energy expenditure of locomotion in horses

Journal of Experimental Biology ◽

10.1242/jeb.202.17.2329 ◽

1999 ◽

Vol 202 (17) ◽

pp. 2329-2338 ◽

Cited By ~ 25

Author(s):

A.E. Minetti ◽

L.P. Ardigò ◽

E. Reinach ◽

F. Saibene

Keyword(s):

Energy Expenditure ◽

Elastic Energy ◽

Three Dimensional ◽

Indirect Evidence ◽

The Body ◽

Mechanical Work ◽

Metabolic Energy ◽

Centre Of Mass ◽

External Work ◽

Metabolic Energy Expenditure

Three-dimensional motion capture and metabolic assessment were performed on four standardbred horses while walking, trotting and galloping on a motorized treadmill at different speeds. The mechanical work was partitioned into the internal work (W(INT)), due to the speed changes of body segments with respect to the body centre of mass, and the external work (W(EXT)), due to the position and speed changes of the body centre of mass with respect to the environment. The estimated total mechanical work (W(TOT)=W(INT)+W(EXT)) increased with speed, while metabolic work (C) remained rather constant. As a consequence, the ‘apparent efficiency’ (eff(APP)=W(TOT)/C) increased from 10 % (walking) to over 100 % (galloping), setting the highest value to date for terrestrial locomotion. The contribution of elastic structures in the horse's limbs was evaluated by calculating the elastic energy stored and released during a single bounce (W(EL,BOUNCE)), which was approximately 1.23 J kg(−)(1) for trotting and up to 6 J kg(−)(1) for galloping. When taking into account the elastic energy stored by the spine bending and released as W(INT), as suggested in the literature for galloping, W(EL,BOUNCE) was reduced by 0.88 J kg(−)(1). Indirect evidence indicates that force, in addition to mechanical work, is also a determinant of the metabolic energy expenditure in horse locomotion.

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Scanning electron microscopy of freeze-fractured prescapular lymph node of caprine

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111331 ◽

1984 ◽

Vol 42 ◽

pp. 244-245

Author(s):

O. Faroon ◽

F. Al-Bagdadi ◽

T. G. Snider ◽

C. Titkemeyer

Keyword(s):

Lymph Node ◽

Lymph Nodes ◽

Lymphatic System ◽

Three Dimensional ◽

Meat Products ◽

The Body ◽

Morphological Data ◽

The World ◽

Cellular Constituent ◽

Scanning Electron

The lymphatic system is very important in the immunological activities of the body. Clinicians confirm the diagnosis of infectious diseases by palpating the involved cutaneous lymph node for changes in size, heat, and consistency. Clinical pathologists diagnose systemic diseases through biopsies of superficial lymph nodes. In many parts of the world the goat is considered as an important source of milk and meat products.The lymphatic system has been studied extensively. These studies lack precise information on the natural morphology of the lymph nodes and their vascular and cellular constituent. This is due to using improper technique for such studies. A few studies used the SEM, conducted by cutting the lymph node with a blade. The morphological data collected by this method are artificial and do not reflect the normal three dimensional surface of the examined area of the lymph node. SEM has been used to study the lymph vessels and lymph nodes of different animals. No information on the cutaneous lymph nodes of the goat has ever been collected using the scanning electron microscope.

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Thermal characterization of ABS-Graphene blended three dimensional printed functional prototypes for electro chemical energy storage

International Journal of Computational Physics Series ◽

10.29167/a1i1p1-11 ◽

2018 ◽

Vol 1 (1) ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Kamaljit Singh Boparai ◽

Rupinder Singh

Keyword(s):

Energy Storage ◽

Structural Changes ◽

Fused Deposition Modeling ◽

Morphological Changes ◽

Three Dimensional ◽

Thermal Characterization ◽

Chemical Energy ◽

Flow Index ◽

Fused Deposition

This study highlights the thermal characterization of ABS-Graphene blended three dimensional (3D) printed functional prototypes by fused deposition modeling (FDM) process. These functional prototypes have some applications as electro-chemical energy storage devices (EESD). Initially, the suitability of ABS-Graphene composite material for FDM applications has been examined by melt flow index (MFI) test. After establishing MFI, the feedstock filament for FDM has been prepared by an extrusion process. The fabricated filament has been used for printing 3D functional prototypes for printing of in-house EESD. The differential scanning calorimeter (DSC) analysis was conducted to understand the effect on glass transition temperature with the inclusion of Graphene (Gr) particles. It has been observed that the reinforced Gr particles act as a thermal reservoir (sink) and enhances its thermal/electrical conductivity. Also, FT-IR spectra realized the structural changes with the inclusion of Gr in ABS matrix. The results are supported by scanning electron microscopy (SEM) based micrographs for understanding the morphological changes.

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