Dynamics of tracheal compression in the horned passalus beetle

2013 ◽  
Vol 304 (8) ◽  
pp. R621-R627 ◽  
Author(s):  
James S. Waters ◽  
Wah-Keat Lee ◽  
Mark W. Westneat ◽  
John J. Socha
Keyword(s):  
Dynamical Behavior ◽  
The Body ◽  
Reverse Direction ◽  
Effective Diameter ◽  
Contrast Imaging ◽  
Tracheal System ◽  
Tracheal Compression ◽  
Internal Mixing ◽  
Respiratory Gases ◽  
Opening And Closing

Rhythmic patterns of compression and reinflation of the thin-walled hollow tubes of the insect tracheal system have been observed in a number of insects. These movements may be important for facilitating the transport and exchange of respiratory gases, but observing and characterizing the dynamics of internal physiological systems within live insects can be challenging due to their size and exoskeleton. Using synchrotron X-ray phase-contrast imaging, we observed dynamical behavior in the tracheal system of the beetle, Odontotaenius disjunctus. Similar to observations of tracheal compression in other insects, specific regions of tracheae in the thorax of O. disjunctus exhibit rhythmic collapse and reinflation. During tracheal compression, the opposing sides of a tracheal tube converge, causing the effective diameter of the tube to decrease. However, a unique characteristic of tracheal compression in this species is that certain tracheae collapse and reinflate with a wavelike motion. In the dorsal cephalic tracheae, compression begins anteriorly and continues until the tube is uniformly flattened; reinflation takes place in the reverse direction, starting with the posterior end of the tube and continuing until the tube is fully reinflated. We report the detailed kinematics of this pattern as well as additional observations that show tracheal compression coordinated with spiracle opening and closing. These findings suggest that tracheal compression may function to drive flow within the body, facilitating internal mixing of respiratory gases and ventilation of distal regions of the tracheal system.

Pressure cycles and the water economy of insects

1988 ◽  
Vol 318 (1190) ◽  
pp. 377-407 ◽  
Keyword(s):  
Body Temperature ◽  
Water Exchange ◽  
Vapour Phase ◽  
The Body ◽  
Tracheal System ◽  
Water Economy ◽  
Insect Wings ◽  
Pressure Cycle ◽  
Respiratory Gases

Water exchange between insects and their environment via the vapour phase includes influx and efflux components. The pressure cycle theory postulates that insects (and some other arthropods) can regulate the relative rates of influx and efflux of water vapour by modulating hydrostatic pressures at a vapour-liquid interface by compressing or expanding a sealed, gas-filled cavity. Some such cavities, like the tracheal system, could be compressed by elevated pressure in all or part of the haemocoele. Others, perhaps including the muscular rectum of flea prepupae, could be compressed by intrinsic muscles. Maddrell Insect Physiol . 8, 199 (1971)) suggested a pressure cycle mechanism of this kind to account for rectal uptake of water vapour in Thermobia but did not find it compatible with quantitative information then available. Newer evidence conforms better with the proposed mechanism. Cyclical pressure changes are of widespread occurrence in insects and have sometimes been shown to depend on water status. Evidence is reviewed for the role of the tracheal system as an avenue for net exchange of water between the insect and its environment. Because water and respiratory gases share common pathways, most published findings fail to distinguish between the conventional view that the tracheal system has evolved as a site for distribution and exchange of respiratory gases and that any water exchange occurring in it is generally incidental and nonadaptive, and the theory proposed here. The pressure cycle theory offers a supplementary explanation not incompatible with evidence so far available. The relative importance of water economy and respiratory exchange in the functioning of compressible cavities such as the tracheal system remains to be explored. Some further implications of the pressure cycle theory are discussed. Consideration is given to the possible involvement of vapour-phase transport in the internal redistribution of water within the body. It is suggested that some insect wings may constitute internal vapour-liquid exchange sites, where water can move from the body fluids to the intratracheal gas. Ambient and body temperature must influence rates of vapour-liquid mass transfer. If elevated body temperature promotes evaporative discharge of the metabolic water burden that has been shown to accumulate during flight in some large insects, their minimum threshold thoracic temperature for sustained flight may relate to the maintenance of water balance. The role of water economy in the early evolution of insect wings is considered. Pressure cycles might help to maintain water balance in surface-breathing insects living in fresh and saline waters, but the turbulence of the surface of the open sea might prevent truly marine forms from using this mechanism.

scholarly journals Energy balances of eight volunteers fed on diets supplemented with either lac ti to1 or saccharose

1986 ◽  
Vol 56 (3) ◽  
pp. 545-554 ◽  
Author(s):  
A. J. H. Van Es ◽  
Lisette De Groot ◽  
J. E. Vogt
Keyword(s):  
Basal Diet ◽  
Open Circuit ◽  
The Body ◽  
Metabolizable Energy ◽  
Office Work ◽  
Accurate Picture ◽  
Within Subjects ◽  
Energy Equilibrium ◽  
The Difference ◽  
Respiratory Gases

1. Complete 24 h energy and nitrogen balances were measured for eight subjects both while consuming a basal diet supplemented with 49 g saccharose/d (diet S) and while consuming the same basal diet but supplemented with 50 g lactitol monohydrate/d (diet L).2. The subjects ate the two diets for 8 d. Faeces and urine were collected for the final 4 d. Exchange of respiratory gases (oxygen, carbon dioxide, hydrogen and methane) was measured during the final 72 h while the subjects stayed in an open-circuit respiration chamber, 11 m3, and simulated office work. Before eating diet L, subjects ate 50 g lactitol daily for 10 d.3. On diets L and S, faecal moisture content averaged 0.787 and 0.753 g/g respectively, the difference being significant (P < 0.05). On diet L, energy and nitrogen digestibilities and energy metabolizability averaged 0, 922, 0.836 and 0-881 respectively, and on diet S 0.935, 0.869 and 0.896 respectively; the differences were also significant (P < 0.05). Urinary energy losses and N balances were not significantly different for the two diets.4. In all subjects only traces of methane were produced but hydrogen production differed significantly (P < 0.05) for diets L and S, being 2.3 and 0.4 litres (normal temperature and pressure)/d respectively.5. Intakes of metabolizable energy (ME) were corrected, within subjects, to energy equilibrium and equal metabolic body-weight. The corrected ME intakes did not show differences between diets. However, when on diet L the subjects were probably less active than when on diet S because differences within subjects of ankle actometer counts between diets showed a high correlation with the corresponding differences in corrected ME intakes (r 0.92). Further correction of ME intake toward equal actometer activity showed a significant (P < 0.05) difference between diets: for maintaining energy equilibrium 5.6 (SE 0.8; P < 0.05) % more ME from diet L was needed than from diet S. The reliability of this 5.6% difference depends on whether or not one ankle actometer gives an accurate picture of the subject's physical activity.6. The energy contribution to the body is clearly smaller from lactitol than from saccharose, certainly due to the effect of lactitol on digestion, and probably also due to the effect on the utilization of ME.

The Evaporation of Water from the Cockroach

1935 ◽  
Vol 12 (4) ◽  
pp. 373-383 ◽  
Author(s):  
J. A. RAMSAY
Keyword(s):  
Wind Velocity ◽  
Body Surface ◽  
Periplaneta Americana ◽  
The Body ◽  
Tracheal System ◽  
Physical Systems ◽  
Change Of State ◽  
Fatty Substance ◽  
Effects Of Temperature ◽  
Rate Of Evaporation

1. The effects of temperature, humidity and wind velocity upon the rate of evaporation of water from the cockroach Periplaneta americana have been studied. 2. The effects of these factors upon the rate of evaporation from the tracheal system are shown to be similar to their effects upon purley physical systems. 3. The effects of these factors upon the rate of evaporation from the body surface are shown to be complicated by the presence of a film of fatty substance which undergoes a change of state at about 30° C.

Development of the Drosophila tracheal system occurs by a series of morphologically distinct but genetically coupled branching events

Development ◽  
1996 ◽  
Vol 122 (5) ◽  
pp. 1395-1407 ◽  
Author(s):  
C. Samakovlis ◽  
N. Hacohen ◽  
G. Manning ◽  
D.C. Sutherland ◽  
K. Guillemin ◽  
...  
Keyword(s):  
Tube Formation ◽  
The Body ◽  
Terminal Branch ◽  
Cellular Mechanisms ◽  
Morphological Marker ◽  
Tracheal System ◽  
Fgf Receptor ◽  
Restricted Domains ◽  
Gene Regulatory ◽  
Ets Domain

The tracheal (respiratory) system of Drosophila melanogaster is a branched network of epithelial tubes that ramifies throughout the body and transports oxygen to the tissues. It forms by a series of sequential branching events in each hemisegment from T2 to A8. Here we present a cellular and initial genetic analysis of the branching process. We show that although branching is sequential it is not iterative. The three levels of branching that we distinguish involve different cellular mechanisms of tube formation. Primary branches are multicellular tubes that arise by cell migration and intercalation; secondary branches are unicellular tubes formed by individual tracheal cells; terminal branches are subcellular tubes formed within long cytoplasmic extensions. Each level of branching is accompanied by expression of a different set of enhancer trap markers. These sets of markers are sequentially activated in progressively restricted domains and ultimately individual tracheal cells that are actively forming new branches. A clonal analysis demonstrates that branching fates are not assigned to tracheal cells until after cell division ceases and branching begins. We further show that the breathless FGF receptor, a tracheal gene required for primary branching, is also required to activate expression of markers involved in secondary branching and that the pointed ETS-domain transcription factor is required for secondary branching and also to activate expression of terminal branch markers. The combined morphological, marker expression and genetic data support a model in which successive branching events are mechanistically and genetically distinct but coupled through the action of a tracheal gene regulatory hierarchy.

scholarly journals Acardiac Twin

2014 ◽  
Vol 2 (2) ◽  
pp. 77-80 ◽  
Author(s):  
MS Maherunnessa ◽  
Rahima Begum ◽  
Samsad Jahan ◽  
Shamsunnahar Bela ◽  
Syeda Riffat Binta Habib ◽  
...  
Keyword(s):  
Twin Pregnancy ◽  
Umbilical Artery ◽  
Rare Complication ◽  
Multiple Pregnancy ◽  
The Body ◽  
Reverse Direction ◽  
Arterial Perfusion ◽  
Blood Flows ◽  
Acardiac Twin ◽  
Pump Twin

Acardiac anomaly is a rare complication of multiple pregnancies. It is a hemodyamically disadvantaged nonviable twin which occurs in association with a twin reversed arterial perfusion sequence (TRAP). In TRAP, blood flows from an umbilical artery of the pump twin in reverse direction into umbilical artery of the perfused (or acardiac) twin via an arterial to arterial (AA) anastomosis. Its blood is poorly oxygenated and results in variable degrees of deficient development of the head, heart, and upper limb structures. The lower half of the body is usually better developed, which may be explained by the mechanism of perfusion. The pump twin is at risk of heart failure and problems related to preterm birth with a reported mortality of 50-75%. We present a case of multiple pregnancy with acardiac twin in a 26 year old lady with gestational diabetes mellitus. During ante natal check up several ultrasonographic (USG) screening showed twin pregnancy with one healthy fetus and the other fetus with inconspicuous anatomy and structure. Repeat USG at 36th week of gestation diagnosed twin pregnancy with acardiac twin. Strikingly the pump twin did not develop the usual complications and was delivered by cesarean section at 37th week of gestation. DOI: http://dx.doi.org/10.3329/dmcj.v2i2.20529 Delta Med Col J. Jul 2014; 2(2): 77-80

scholarly journals The Dynamical Behavior of a Rigid Body Relative Equilibrium Position

2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
T. S. Amer
Keyword(s):  
Rigid Body ◽  
Degrees Of Freedom ◽  
Numerical Solutions ◽  
Equations Of Motion ◽  
Relative Equilibrium ◽  
Dynamical Behavior ◽  
Vertical Plane ◽  
The Body ◽  
Physical Parameters ◽  
Pendulum Model

In this paper, we will focus on the dynamical behavior of a rigid body suspended on an elastic spring as a pendulum model with three degrees of freedom. It is assumed that the body moves in a rotating vertical plane uniformly with an arbitrary angular velocity. The relative periodic motions of this model are considered. The governing equations of motion are obtained using Lagrange’s equations and represent a nonlinear system of second-order differential equations that can be solved in terms of generalized coordinates. The numerical solutions are investigated using the fourth-order Runge-Kutta algorithms through Matlab packages. These solutions are represented graphically in order to describe and discuss the behavior of the body at any instant for different values of the physical parameters of the body. The obtained results have been discussed and compared with some previous published works. Some concluding remarks have been presented at the end of this work. The importance of this work is due to its numerous applications in life such as the vibrations that occur in buildings and structures.

A Novel Bio-Inspired Pneumatic Valve Adapter for Soft Robotic Vasculature

2020 ◽  
Author(s):  
Benjamin O. Saunders ◽  
John P. Swensen
Keyword(s):  
The Body ◽  
Outer Tube ◽  
Soft Robotics ◽  
Tube System ◽  
Pressure Flow ◽  
Pneumatic Valve ◽  
Cardiovascular Systems ◽  
Opening And Closing

Abstract This paper proposes a novel pneumatic valve adapter that decreases the size and quantity of pneumatic tubes and valves necessary for soft robotics by mimicking cardiovascular systems. Some cardiovascular systems, evolved to be powered by a single reservoir, the heart, which in turn powers the rest of the body by systematically opening and closing valves as needed. The presented valve adapter consists of a set of concentric tube, where both tubes have strategically patterned holes. The inner tube can be moved translationally and rotationally to align with designated hole positions in the outer tube, thus opening and closing pathways to chambers for pressure flow. The two-tube system can be used to either pressurize a chamber or depressurize a chamber or multiple chambers simultaneously.

scholarly journals In vivo continuous three-dimensional magnetic resonance microscopy: a study of metamorphosis in Carniolan worker honey bees (Apis mellifera carnica)

2020 ◽  
Vol 223 (21) ◽  
pp. jeb225250
Author(s):  
Aleš Mohorič ◽  
Janko Božič ◽  
Polona Mrak ◽  
Kaja Tušar ◽  
Chenyun Lin ◽  
...  
Keyword(s):  
Apis Mellifera ◽  
Magnetic Resonance ◽  
Time Course ◽  
Three Dimensional ◽  
The Body ◽  
Magnetic Resonance Microscopy ◽  
Tracheal System ◽  
Apis Mellifera Carnica ◽  
Occurrence Matrix

ABSTRACTThree-dimensional (3D) magnetic resonance microscopy (MRM) is a modality of magnetic resonance imaging (MRI) optimized for the best resolution. Metamorphosis of the Carniolan worker honey bee (Apis mellifera carnica) was studied in vivo under controlled temperature and humidity conditions from sealed larvae until the emergence of an adult. The 3D images were analyzed by volume rendering and segmentation, enabling the analysis of the body, tracheal system and gastrointestinal tract through the time course of volume changes. Fat content sensitivity enabled the analysis of flight muscles transformation during the metamorphosis by the signal histogram and gray level co-occurrence matrix (GLCM). Although the transformation during metamorphosis is well known, MRM enables an alternative insight to this process, i.e. 3D in vivo, which has relatively high spatial and temporal resolutions. The developed methodology can easily be adapted for studying the metamorphosis of other insects or any other incremental biological process on a similar spatial and temporal scale.

scholarly journals The Development of Body-Powered Prosthetic Hand Controlled by EMG Signals Using DSP Processor with Virtual Prosthesis Implementation

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Fathia H. A. Salem ◽  
Khaled S. Mohamed ◽  
Sundes B. K. Mohamed ◽  
Amal A. El Gehani
Keyword(s):  
High Performance ◽  
State Of The Art ◽  
The Body ◽  
Prosthetic Hand ◽  
Prosthetic Hands ◽  
Emg Signal ◽  
Mechanical Hand ◽  
Fast Processing ◽  
Opening And Closing ◽  
Two Stages

The state of the art in the technology of prosthetic hands is moving rapidly forward. However, there are only two types of prosthetic hands available in Libya: the Passive Hand and the Mechanical Hand. It is very important, therefore, to develop the prosthesis existing in Libya so that the use of the prosthesis is as practical as possible. Considering the case of amputation below the elbow, with two movements: opening and closing the hand, this work discusses two stages: developing the operation of the body-powered prosthetic hand by controlling it via the surface electromyography signal (sEMG) through dsPIC30f4013 processor and a servo motor and a software based on fuzzy logic concept to detect and process the EMG signal of the patient as well as using it to train the patient how to control the movements without having to fit the prosthetic arm. The proposed system has been practically implemented, tested, and gave satisfied results, especially that the used processor provides fast processing with high performance compared to other types of microcontrollers.

scholarly journals The regulation of respiration in the flea, xenopsylla cheopis , Roths. (Pulicidea)

1935 ◽  
Vol 118 (810) ◽  
pp. 397-419 ◽  
Keyword(s):  
Diffusion Control ◽  
Regulation Of Respiration ◽  
Tracheal System ◽  
Xenopsylla Cheopis ◽  
The Common ◽  
Pass Through ◽  
Terrestrial Insects ◽  
Opening And Closing ◽  
The Tropics ◽  
Mechanical Aeration

The gaseous exchanges of terrestrial insects are regulated by (i) the opening and closing of the spiracles—the “diffusion control” of Hazelhoff (1926, 1927)—and, in the larger and more active forms by (ii) the mechanical aeration of the tracheal system by pumping movements—“ventilation control.” Spiracular and pumping movements may occur at the same time; for example, in those insects in which a directed stream of air is driven through the main tracheal branches (Fraenkel, 1932; McGovran, 1931); and then the spiracles, by allowing air to pass through them in one direction only, are believed to play a part in the mechanism of ventilation. The object of the present work was to study in greater detail than hitherto the spiracular movements of an insect in which these are not complicated by mechanical ventilation. For this purpose the common rat flea of the tropics, Xenopsylla cheopis , has proved an ideal subject.

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