Sensory Regulation of Wing Twisting in Locusts

1966 ◽  
Vol 44 (1) ◽  
pp. 1-16
Author(s):  
ERIK GETTRUP
Keyword(s):  
Hind Wing ◽  
Ventral Surface ◽  
The Body ◽  
Flight Period ◽  
Campaniform Sensilla ◽  
Motor Patterns ◽  
Body Angle ◽  
Central Processing ◽  
Sensory Regulation ◽  
Three Body

1. The campaniform sensilla of the wings are necessary for the regulation of wing twisting in locusts. Control of forewing twisting during periods of constant lift depends upon the hind-wing sensilla being intact, whereas the forewing sensilla are essential for stability about the three body axes. 2. The campaniform sensilla are located on the ventral surface of the wings. Two groups are present on the subcosta of the forewing and one on the subcosta of the hind-wing. A few single sensilla occur on the costa. The cuticular parts of sensilla from distal and proximal forewing groups differ with respect to the lengths of their ovally shaped cuticular parts. The sensilla are orientated with the cupolas parallel to the long axis of the wing, except for those of the proximal forewing group, which are arranged in a fan. 3. During steady-state flights activity from campaniform units was high during the downstroke and low during the first part of the upstroke. Significant changes in the response were found to occur when the body angle was changed. 4. The effect of a 15° change in body angle on the motor output to the basalar and subalar muscles is described. At the start of a flight these motor patterns are rather unstable, units falling in and out. Stability is gained within 10 sec. 5. A distinct part of the response from the campaniform units in the hindwings can be abolished by the application of an anodic block. The duration of the blocking pulse equalled one-sixth of the flight period. The effect on regulation of forewing twisting varied according to the part of the response which is removed. Regulation could be abolished almost completely when the anodic block was introduced during the first part of the hindwing downstroke. When the anodic block is removed, twist regulation builds up again and is completed within 100-150 wing-beats. 6. Free flights including both intact and deafferentated animals made possible an evaluation of the importance of the different groups in stability reactions. It was shown that control of angular movement is accomplished by the forewing groups only, especially the proximal ones. 7. The integrative processes within the pterothoracic ganglia are discussed. During the constant-lift reaction, the slow, intersegmental reflex for control of forewing twisting seems to depend on central processing and memorizing of measurements of total lift. The sensory input from the hindwings is phasic and patterned, but it is still undecided whether it is the phase or the pattern which is the essential parameter.

The external sensory morphology of the legs and hairplate system of female Trichogramma minutum Riley (Hymenoptera: Trichogrammatidae)

1987 ◽  
Vol 232 (1268) ◽  
pp. 323-366 ◽  
Keyword(s):  
Body Size ◽  
Neck Region ◽  
Dorsal Surface ◽  
Parasitoid Wasp ◽  
Ventral Surface ◽  
Distal Portion ◽  
The Body ◽  
Single Pair ◽  
Campaniform Sensilla ◽  
Trichogramma Minutum

This work continues a comprehensive description of the external sensory morphology of the parasitoid wasp Trichogramma minutum . All sensilla and associated structures identified by electron microscopy are described. In addition, this study also includes the hairplates associated with the antennae and neck region. The majority of sensilla appear to be mechanosensory, and are either trichoid or campaniform in structure. Large, socketed setae (10–50 μm long) are found on all leg segments, but vary considerably in body size and shape, depending upon location. On the tibial and tarsal segments of the pro- and metathoracic legs some of the larger hairs have been modified to form antennal and wing combs. On both the meso- and metathoracic legs a distal tibial seta is greatly enlarged and functions as a socketed spur. The sensilla that compose the hairplates are relatively short (1–3 μm) and differ in socket morphology from the longer setae located elsewhere on the body surface. Hairplates occur on the dorsal surface of the trochanter at the coxatrochanteral joint, on the distal portion of the coxae, around the neck on the dorsal and ventral surfaces of the episternum, and the opening of the postocciput. The most complex arrangement of hairplates surrounds the distal portion of the scape, and comprises four separate groups of hairs. Hairplates are also located on the dorsal and lateral surfaces of the proximal end of the pedicellus. Nine to eleven campaniform sensilla are located on the trochanter of each leg. The proximal subdivision of the femur is equipped with six sensilla grouped together on the ventral surface. Three to five campaniform sensilla are clustered on the dorsal surface of the distal end of the tibia of each leg, and a single pair of sensilla is located at the distal end of the first tarsomere. All the leg campaniform sensilla are elliptical, and 1.5–2.5 μm long. The number, position and morphology of the sensilla was consistent between individuals. The structure and function of these sensory structures are discussed in relation to their role in walking, proprioceptive control of posture, and gravity detection. The scaling of sensilla to body size and homologies with larger insects are also examined, and the possible role of these structures in the detection and measurement of host curvature is considered.

The ultrastructure of the epidermis of the redia and cercaria of Parorchis acanthus, Nicoll. A study by scanning and transmission electron-microscopy

Parasitology ◽  
1971 ◽  
Vol 62 (3) ◽  
pp. 479-488 ◽  
Author(s):  
Gwendolen Rees
Keyword(s):  
Electron Micrographs ◽  
Technical Assistance ◽  
Ventral Surface ◽  
The Body ◽  
Muscle Fibres ◽  
Scanning Electron Micrographs ◽  
Large Area ◽  
Transmission Electron ◽  
Parorchis Acanthus ◽  
Scanning Electron

Scanning electron-micrographs have shown the covering of microvilli on the surface of the redia of Parorchis acanthus. In the contracted state the elongated microvilli with bulbous extremities seen in the surface grooves may be the result of compression. The surface of the epidermis of the cercaria is smooth on a large area of the ventral surface and lattice-like with microvilli, laterally, anteriorly, dorsally and on the tail. The spines on the body can be withdrawn into sheaths by the contraction of muscle fibres inserted into the basement lamina below each spine.I would like to express my sincere gratitude to Dr I. ap Gwynn of this department for preparing the scanning electron-micrographs and the School of Engineering Science, University of North Wales, Bangor for the use of their stereoscan. I should also like to thank Mr M. C. Bibby for technical assistance and Professor E. G. Gray and Dr W. Sinclair for assistance with the transmission electron-micrographs.

Lepeophtheirus salmonis (Krøyer, 1837): second nauplius and copepodid locomotor appendages, surface areas and possible appendage functions

Crustaceana ◽  
2013 ◽  
Vol 86 (13-14) ◽  
pp. 1695-1710 ◽  
Author(s):  
Susan E. Allen ◽  
A. G. Lewis
Keyword(s):  
Body Position ◽  
Ventral Surface ◽  
Total Surface Area ◽  
The Body ◽  
Lepeophtheirus Salmonis ◽  
Sinking Rate ◽  
Surface Areas ◽  
Thoracic Legs ◽  
Two Stages ◽  
Suitable Location

Locomotor appendage-body relationships were used to examine whether swimming or reduction in sinking rate is the more important function in the second nauplius and copepodid stages of Lepeophtheirus salmonis (Krøyer, 1837). Except for the similarity in swimming appendage surface areas without setae, the appendages of the two stages are morphologically distinct. Although the nauplius is smaller than the copepodid it has long slender appendages that, with setae, provide greater total surface area than the paddle-shaped copepodid thoracic legs. Copepodid thoracic legs are more similar to those used for swimming by planktonic copepods although with more limited propulsion capability. Naupliar appendages project from the body while copepodid appendages can be folded against the ventral surface, improving hydrodynamic flow as well as body position after attachment to a host. Both copepodid and naupliar appendages are of sufficient size that they should provide escape velocities of more than 100 mm ⋅ s−1. The nature and display of the naupliar appendages suggest they could be used to reduce sinking rate by as much as 64%, reducing the need to swim to maintain a suitable location in the water. Although copepodid thoracic legs could reduce sinking rate by over 40%, their position on the ventral surface and the nature of other appendages suggests a more important use, for orientation and attachment once a host is located.

scholarly journals Hovering performance of Anna's hummingbirds ( Calypte anna ) in ground effect

2014 ◽  
Vol 11 (98) ◽  
pp. 20140505 ◽  
Author(s):  
Erica J. Kim ◽  
Marta Wolf ◽  
Victor Manuel Ortega-Jimenez ◽  
Stanley H. Cheng ◽  
Robert Dudley
Keyword(s):  
Wing Length ◽  
Ground Effect ◽  
The Body ◽  
Plane Angle ◽  
Metabolic Power ◽  
Wingbeat Frequency ◽  
Body Angle ◽  
Induced Flow ◽  
Induced Velocity ◽  
Calypte Anna

Aerodynamic performance and energetic savings for flight in ground effect are theoretically maximized during hovering, but have never been directly measured for flying animals. We evaluated flight kinematics, metabolic rates and induced flow velocities for Anna's hummingbirds hovering at heights (relative to wing length R = 5.5 cm) of 0.7 R , 0.9 R , 1.1 R , 1.7 R , 2.2 R and 8 R above a solid surface. Flight at heights less than or equal to 1.1 R resulted in significant reductions in the body angle, tail angle, anatomical stroke plane angle, wake-induced velocity, and mechanical and metabolic power expenditures when compared with flight at the control height of 8 R . By contrast, stroke plane angle relative to horizontal, wingbeat amplitude and wingbeat frequency were unexpectedly independent of height from ground. Qualitative smoke visualizations suggest that each wing generates a vortex ring during both down- and upstroke. These rings expand upon reaching the ground and present a complex turbulent interaction below the bird's body. Nonetheless, hovering near surfaces results in substantial energetic benefits for hummingbirds, and by inference for all volant taxa that either feed at flowers or otherwise fly close to plant or other surfaces.

WING MOVEMENTS AND LIFT REGULATION IN THE FLIGHT OF DESERT LOCUSTS

1993 ◽  
Vol 182 (1) ◽  
pp. 57-69 ◽  
Author(s):  
M. Wortmann ◽  
W. Zarnack
Keyword(s):  
Body Weight ◽  
Unsteady Aerodynamics ◽  
Movement Patterns ◽  
The Body ◽  
Three Dimensions ◽  
Body Angle ◽  
Wing Movement ◽  
Induced Changes ◽  
Lift Body

1. We simultaneously recorded lift/body weight, flight speed, body angle and 12 variables of wing movement for locusts performing tethered long-term flight with low movement scatter. The movements of the forewings and hindwings were recorded in three dimensions by means of miniature induction coils. 2. By adjusting the body angle, we could reproducibly manipulate lift generation as a consequence of induced changes in the wings' movement patterns. We were therefore able to analyse various relationships between the movement patterns and lift. 3. The most prominent variations of kinematic variables were observed for the forewing movements. The relative lift and the steady angle of pitch were positively correlated but there was a negative correlation between relative lift and pitching amplitude. We found no correlation between relative lift and flapping amplitude. Our results seem to correspond to a new theory about unsteady aerodynamics of oscillating aerofoils. 4. We sometimes observed variations in lagging. 5. The forewing downstroke was delayed by 0–8 ms following the hindwing downstroke. Relative lift was positively correlated to this delay.

scholarly journals FOSSA NAVICULARIS MAGNA AT THE SKULL BASE: EMBRYOGENESIS AND ITS DETECTION BY COMPUTED TOMOGRAPHY

2018 ◽  
Vol 99 (3) ◽  
pp. 153-157
Author(s):  
S. L. Kabak ◽  
V. V. Zatochnaya ◽  
Yu. M. Mel’nichenko ◽  
N. A. Savrasova ◽  
E. A. Dorokh
Keyword(s):  
Computed Tomography ◽  
Congenital Anomaly ◽  
Skull Base ◽  
Paranasal Sinuses ◽  
Ventral Surface ◽  
The Body ◽  
Spiral Computed ◽  
Edge Defect ◽  
Medical Centers ◽  
Fossa Navicularis

Fossa navicularis magna was detected in multislice spiral computed  tomography in two patients who turned to the medical centers with  pathology of the paranasal sinuses. Its appearance is determined during  the development of the basilar part of the occipital bone and the body of the sphenoid bone in embryogenesis. This fossa has the  appearance of an edge defect on the ventral surface of the clivus in  CBCT scans. Practical radiologist should interpret such a finding as a  congenital anomaly of development, but not as an invasive lesion.

scholarly journals Motor Programs as Indicators of Penalty Direction in Soccer

2020 ◽  
Vol 8 (9) ◽  
pp. 224-233
Author(s):  
Luiz Felipe Pinto Oliveira da Motta ◽  
Ricardo Fontes Macedo ◽  
Elizabeth Cárpio Rivera ◽  
Angela Luciana De-Bortoli ◽  
Robelius De-Bortoli
Keyword(s):  
Behavior Pattern ◽  
Video Camera ◽  
The Body ◽  
Motor Patterns ◽  
Motor Programs ◽  
Front View ◽  
Elbow Angle ◽  
Patterns Of Behavior ◽  
Prior Intention ◽  
Leg Position

Introduction: Many football games are decided on penalties and usually in championship final games. When seeking to anticipate movements, differences in amplitude can harm players because the informational movement appears to be spread "globally" throughout the action and should be coded at several levels. Thus, it would be interesting to analyze the entire period of the kick, since the player begins his run to approach the ball to recognize the motor patterns used in the kick that identify his direction. Objective: The objective of this study is to identify patterns of behavior in penalty kicks that may indicate the direction of their action / kick and in my moment they appear. Methodology: The sample consisted of 21 subjects hitting a penalty kick, 18 males and 3 females with an average age of 22.18 ± 2.44 years and two goalkeepers with college football experience. The tests consisted of a battery of two penalty kicks for each subject in order to score. The kicks were recorded by a video camera with a front view of the goal goal and the back of the batter. The kick phases were divided into the starting leg position; first step leg; angle of the elbow in relation to the body seen from behind; angle of the elbow in relation to the displacement line seen from above; direction of the tip of the supporting foot and position on the goal where the kick was. Each kick was preceded by a start signal. The data were analyzed from the registration of each variable and the position of the goal in which the ball was kicked, considering it in three sectors: left, right and central. Results: The main results indicated that the variable “Leg of the first step” had 81% of the kicks associated with the direction of the goal; 52.4% of second kicks had repeated the pattern of behavior and 84.6% had repeated the pattern of behavior regardless of the goal position. The variable “Elbow angle in relation to the body seen from behind” had 81.8% repeated behavior pattern regardless of the goal position and the variable “Elbow angle in relation to the displacement line seen from above” had 81% association with the sector of the goal in which the ball was kicked; 52.4% of second kicks had repeated the pattern of behavior and 91.7% had repeated the pattern of behavior regardless of the goal position. Conclusions: The main conclusions indicate that it is possible to relate the kick location with the batter's body information; the start of the race seems to indicate that there is a prior intention of movement programs; the decision of where to hit the penalty appears to be made before contact with the ball and more closely to the placement of the support foot and with this relationship, the size of the goal to be defended by the goalkeeper could be reduced, increasing the possibility of defense.

scholarly journals Gastruloids develop the three body axes in the absence of extraembryonic tissues and spatially localised signalling

2017 ◽  
Author(s):  
D.A. Turner ◽  
L. Alonso-Crisostomo ◽  
M. Girgin ◽  
P. Baillie-Johnson ◽  
C. R. Glodowski ◽  
...  
Keyword(s):  
Embryonic Stem ◽  
Model System ◽  
The Body ◽  
Genetic Studies ◽  
Animal Development ◽  
Embryonic Tissues ◽  
Bmp Signalling ◽  
Three Body ◽  
Extraembryonic Tissues

AbstractEstablishment of the three body axes is a critical step during animal development. In mammals, genetic studies have shown that a combination of precisely deployed signals from extraembryonic tissues position the anteroposterior axis (AP) within the embryo and lead to the emergence of the dorsoventral (DV) and left-right (LR) axes. We have used Gastruloids, embryonic organoids, as a model system to understand this process and find that they are able to develop AP, DV and LR axes as well as to undergo axial elongation in a manner that mirror embryos. The Gastruloids can be grown for 160 hours and form derivatives from ectoderm, mesoderm and endoderm. We focus on the AP axis and show that in the Gastruloids this axis is registered in the expression of T/Bra at one pole that corresponds to the tip of the elongation. We find that localisation of T/Bra expression depends on the combined activities of Wnt/β-Catenin and Nodal/Smad2,3 signalling, and that BMP signalling is dispensable for this process. Furthermore, AP axis specification occurs in the absence of both extraembryonic tissues and of localised sources of signalling. Our experiments show that Nodal, together with Wnt/β-Catenin signalling, is essential for the expression of T/Bra but that Wnt signalling has a separable activity in the elongation of the axis. The results lead us to suggest that, in the embryo, the role of the extraembryonic tissues might not be to induce the axes but to bias an intrinsic ability of the embryo to break its initial symmetry and organise its axes.One sentence summaryCulture of aggregates of defined number of Embryonic Stem cells leads to self-organised embryo-like structures which, in the absence of localised signalling from extra embryonic tissues and under the autonomous influence of Wnt and Nodal signalling, develop the three main axes of the body.

Morphology of Anomalocaris canadensis from the Burgess Shale

2014 ◽  
Vol 88 (1) ◽  
pp. 68-91 ◽  
Author(s):  
Allison C. Daley ◽  
Gregory D. Edgecombe
Keyword(s):  
Close Association ◽  
Dorsal Surface ◽  
Ventral Surface ◽  
The Body ◽  
Body Region ◽  
Morphological Description ◽  
Burgess Shale ◽  
Oral Cone ◽  
Stem Lineage ◽  
Posterior Body Region

Recent description of the oral cone of Anomalocaris canadensis from the Burgess Shale (Cambrian Series 3, Stage 5) highlighted significant differences from published accounts of this iconic species, and prompts a new evaluation of its morphology as a whole. All known specimens of A. canadensis, including previously unpublished material, were examined with the aim of providing a cohesive morphological description of this stem lineage arthropod. In contrast to previous descriptions, the dorsal surface of the head is shown to be covered by a small, oval carapace in close association with paired stalked eyes, and the ventral surface bears only the triradial oral cone, with no evidence of a hypostome or an anterior sclerite. The frontal appendages reveal new details of the arthrodial membranes and a narrower cross-section in dorsal view than previously reconstructed. The posterior body region reveals a complex suite of digestive, respiratory, and locomotory characters that include a differentiated foregut and hindgut, a midgut with paired glands, gill-like setal blades, and evidence of muscle bundles and struts that presumably supported the swimming movement of the body flaps. The tail fan includes a central blade in addition to the previously described three pairs of lateral blades. Some of these structures have not been identified in other anomalocaridids, making Anomalocaris critical for understanding the functional morphology of the group as a whole and corroborating its arthropod affinities.

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