scholarly journals Prediction of the trajectory of an irregularly shaped body moving through a resistive medium with high velocities

2017 ◽  
Vol 4 (11) ◽  
pp. 1-10 ◽  
Author(s):  
Elvedin Kljuno ◽  
◽  
Alan Catovic ◽  
Keyword(s):  
Shaped Body ◽  
Resistive Medium

scholarly journals A neuronal ensemble encoding adaptive choice during sensory conflict in Drosophila

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Preeti F. Sareen ◽  
Li Yan McCurdy ◽  
Michael N. Nitabach
Keyword(s):  
Food Choice ◽  
Internal State ◽  
Relevant Information ◽  
Food Choices ◽  
Small Population ◽  
Sensory Conflict ◽  
Shaped Body ◽  
Motor Circuits ◽  
Specific Subset ◽  
Adaptive Choice

AbstractFeeding decisions are fundamental to survival, and decision making is often disrupted in disease. Here, we show that neural activity in a small population of neurons projecting to the fan-shaped body higher-order central brain region of Drosophila represents food choice during sensory conflict. We found that food deprived flies made tradeoffs between appetitive and aversive values of food. We identified an upstream neuropeptidergic and dopaminergic network that relays internal state and other decision-relevant information to a specific subset of fan-shaped body neurons. These neurons were strongly inhibited by the taste of the rejected food choice, suggesting that they encode behavioral food choice. Our findings reveal that fan-shaped body taste responses to food choices are determined not only by taste quality, but also by previous experience (including choice outcome) and hunger state, which are integrated in the fan-shaped body to encode the decision before relay to downstream motor circuits for behavioral implementation.

Morphological characterization of single fan-shaped body neurons in Drosophila melanogaster

2009 ◽  
Vol 336 (3) ◽  
pp. 509-519 ◽  
Author(s):  
Weizhe Li ◽  
Yufeng Pan ◽  
Zhipeng Wang ◽  
Haiyun Gong ◽  
Zhefeng Gong ◽  
...  
Keyword(s):  
Drosophila Melanogaster ◽  
Morphological Characterization ◽  
Shaped Body

Diversity, morphology, and phylogeny of coleoid cephalopods from the Upper Cretaceous Plattenkalks of Lebanon-Part I: Prototeuthidina

2011 ◽  
Vol 85 (2) ◽  
pp. 234-249 ◽  
Author(s):  
Dirk Fuchs ◽  
Neal Larson
Keyword(s):  
Digestive Tract ◽  
Upper Cretaceous ◽  
Soft Part ◽  
Phylogenetic Analyses ◽  
Early Jurassic ◽  
The Other ◽  
Large Collection ◽  
Shaped Body ◽  
Cretaceous Deposits

Morphologic analyses of a large collection of coleoid cephalopods from the Lebanese Upper Cretaceous yielded a much higher diversity than previously assumed and revealed numerous extraordinarily well-preserved, soft-part characters. An analysis of the Prototeuthidina, a gladius-bearing group with a slender torpedo-shaped body, revealed two species:Dorateuthis syriacaandBoreopeltis smithin. sp. Previously unknown soft-part characters, such as the digestive tract, the gills, and the cephalic cartilage considerably improved our knowledge ofD. syriaca.Since none of the investigated specimens show more than eight arms, similarities with modern squids are regarded as superficial.Boreopeltis smithin. sp. is erected on the basis of its comparatively wideParaplesioteuthis-like gladius. The latter species represents the first unambiguous record of this genus in Upper Cretaceous deposits. Phylogenetic analyses indicate that the prototeuthidid clade consists of two lineages. The plesioteuthidid lineage originates from early JurassicParaplesioteuthisand leads toPlesioteuthisandDorateuthis.The other lineage is morphologically more conservative and leads toBoreopeltis.

Simulation of turbulent flow around a tear-shaped body with a tapered flare

2007 ◽  
Vol 52 (8) ◽  
pp. 991-997 ◽  
Author(s):  
S. A. Isaev ◽  
A. N. Mikhalev ◽  
A. G. Sudakov ◽  
A. E. Usachev
Keyword(s):  
Turbulent Flow ◽  
Shaped Body

scholarly journals A neural circuit linking two sugar sensors regulates satiety-dependent fructose drive in Drosophila

2021 ◽  
Author(s):  
Pierre-Yves Musso ◽  
Pierre Junca ◽  
Michael D Gordon
Keyword(s):  
Feeding Behavior ◽  
Synaptic Input ◽  
Neural Circuit ◽  
Internal State ◽  
Calcium Activity ◽  
Shaped Body ◽  
Body Activity ◽  
The Brain

ABSTRACTIngestion of certain sugars leads to activation of fructose sensors within the brain of flies, which then sustain or terminate feeding behavior depending on internal state. Here, we describe a three-part neural circuit that links satiety with fructose sensing. We show that AB-FBl8 neurons of the Fan-shaped body display oscillatory calcium activity when hemolymph glycemia is high, and that these oscillations require synaptic input from SLP-AB neurons projecting from the protocerebrum to the asymmetric body. Suppression of activity in this circuit, either by starvation or genetic silencing, promotes specific drive for fructose ingestion. Moreover, neuropeptidergic signaling by tachykinin bridges fan-shaped body activity and Gr43a-mediated fructose sensing. Together, our results demonstrate how a three-layer neural circuit links the detection of two sugars to impart precise satiety-dependent control over feeding behavior.

scholarly journals A neuronal circuit for vector computation builds an allocentric traveling-direction signal in the Drosophila fan-shaped body

2020 ◽  
Author(s):  
Cheng Lyu ◽  
L.F. Abbott ◽  
Gaby Maimon
Keyword(s):  
Computational Models ◽  
Neuronal Population ◽  
The Body ◽  
Central Complex ◽  
Two Dimensional ◽  
Neuronal Circuit ◽  
Head Direction ◽  
Neural Signals ◽  
Shaped Body ◽  
External Cues

AbstractMany behavioral tasks require the manipulation of mathematical vectors, but, outside of computational models1–8, it is not known how brains perform vector operations. Here we show how the Drosophila central complex, a region implicated in goal-directed navigation8–14, performs vector arithmetic. First, we describe neural signals in the fan-shaped body that explicitly track a fly’s allocentric traveling direction, that is, the traveling direction in reference to external cues. Past work has identified neurons in Drosophila12,15–17 and mammals18,19 that track allocentric heading (e.g., head-direction cells), but these new signals illuminate how the sense of space is properly updated when traveling and heading angles differ. We then characterize a neuronal circuit that rotates, scales, and adds four vectors related to the fly’s egocentric traveling direction–– the traveling angle referenced to the body axis––to compute the allocentric traveling direction. Each two-dimensional vector is explicitly represented by a sinusoidal activity pattern across a distinct neuronal population, with the sinusoid’s amplitude representing the vector’s length and its phase representing the vector’s angle. The principles of this circuit, which performs an egocentric-to-allocentric coordinate transformation, may generalize to other brains and to domains beyond navigation where vector operations or reference-frame transformations are required.

Growth of wedge-shaped plutons at the base of active half-grabens

2004 ◽  
Vol 95 (1-2) ◽  
pp. 309-317 ◽  
Author(s):  
S. W. Richards ◽  
W. J. Collins
Keyword(s):  
High Temperature ◽  
Structural Model ◽  
Tectonic Setting ◽  
Shear Bands ◽  
Shaped Body ◽  
The Core ◽  
Lachlan Orogen ◽  
Eastern Australia ◽  
Back Arc ◽  
East West

ABSTRACTCombined field and geophysical data show that plutons from the Bega Batholith are elongate, meridional, wedge-shaped bodies which intruded during a period of regional east–west extension in the Palaeozoic eastern Lachlan orogen, eastern Australia. Plutons within the core of the batholith have intruded coeval, syn-rift sediments and co-magmatic volcanics. The batholith is bound by high-temperature, dip-slip faults, and contains several major NE-trending transtensional faults which were active during batholith construction. In the central part of the batholith, the Kameruka pluton is an asymmetric, eastward-thickening, wedge-shaped body with the base exposed as the western contact, which is characterised by abundant, shallow-dipping schlieren migmatites which contain recumbent folds and extensional shear bands. A shallow (<30°), east-dipping, primary magmatic layering in the Kameruka pluton steepens progressively westward, where it becomes conformable to the east-dipping basal migmatites. The systematic steepening of the layering is comparable to sedimentary units formed during floor depression in syn-rift settings. The present authors suggest that the wedge-shaped plutons of the Bega Batholith are the deeper, plutonic expression of a hot, active rift. The batholith was fed and sustained by injection of magma through sub-vertical dykes. Displacement along syn-magmatic, NE-trending faults suggests up to 25 km of arc-perpendicular extension during batholith construction. The inferred tectonic setting for batholith emplacement is a continental back-arc, where modern half-extension rates of 20–40 mm yr−1 are not unusual, and are sufficient to emplace the entire batholith in ∼1 Ma. This structural model provides a mechanism for the emplacement of some wedge-shaped plutons and is one solution to the ‘room problem’ of batholith emplace

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