scholarly journals An internal expectation guides Drosophila egg-laying decisions

2021 ◽  
Author(s):  
Vikram Vijayan ◽  
Zikun Wang ◽  
Vikram Chandra ◽  
Arun Chakravorty ◽  
Rufei Li ◽  
...  

When presented with two egg-laying substrates, Drosophila lay most of their eggs on the option with higher relative value. How do flies make this relative-value decision? Might the strategy they use allow them to choose the best option even when they experience substrates with a more complex spatiotemporal profile than in canonical two-choice paradigms? We measured Drosophila egg-laying behavior in diverse substrate environments. In all cases, we found that flies dynamically increase or decrease their egg-laying rates as they explore substrates for a deposition site so as to target eggs to the best, recently visited option. Visiting the best option typically led to a strong reduction in egg laying on other substrates for several minutes, with this timescale varying across fly strains. Our data support a model in which flies compare the value of the current substrate with an internally constructed expectation on the value of available options to regulate the likelihood of laying an egg. We show that dopamine-neuron activity is critical for learning and/or expressing this expectation, similar to its role in certain tasks in vertebrates. Integrating sensory experiences over minutes to generate an internal sense of the quality of available options, i.e., forming an expectation, allows flies to use a dynamic reference point for judging the current substrate and might be a general way in which decisions are made, even beyond flies and egg laying.

10.12737/1986 ◽  
2013 ◽  
Vol 1 (6) ◽  
pp. 3-7
Author(s):  
��������� ◽  
Elena Safronova

In the article it is considered the author�s methods of valuating a quality of a patriotic education at a secondary school, which is expressed in capturing of a patriotic activity experience. The structure of experience is a unity of three components: emotional-sensory (experiences, feelings, emotions about events, phenomena of patriotism); relational (relating to facts, phenomena and events of patriotism); efficient-practical (forms of activities, patriotic actions). Herewith the experience of patriotic expression as a social sense is considered to be a component of schoolchild�s personal achievements in educational process, that corresponds to its interpretation in Federal State Educational Standards of secondary (full) general education. The quality of patriotic education is measured with such diagnostics as �Program of Monitoring Expressing Emotions and Feelings by a Teenager due to Events and Phenomena of Patriotism�, �Methods of Valuating the Formation of the Patriotic Attitude (on basis of valuating scale)�, �Methods of Graphic Testing�, integrated methods �Monitoring the Character of Pedagogical Interaction between. In the article there is also a meaning of the integrated approach as a methodological reference point in projecting and valuating the process and the result of patriotic education.


Among the animals of different species chickens react in greater numbers and more noticeable to a va-riety of growth biostimulators. There are great improvements on their general state, growth spurts and development of internal organs is quicker when they are injected with small portions. Such stimulation has a great influence not only on growth and development of chickens in their first period of life but also on health and productivity later on. The most active peak of reaction is when chicken is two months old. Their internal organs, especially the digestive system, develop earlier, their genitals appear earlier and they begin egg-laying much earlier too, when chickens are being fed those biostimulants. Slaughter meat yield becomes more and quality of meat improves with the influence of stimulators. A major disease pre-vention and healing effect can be reached, since most of the biostimulants raise immune system and re-sistance of the organism. It can be the only thing to justify their usage on animals. Tests show that the most typical growth spurt of birds is from fifteen to twenty percent in normal conditions. Growth spurts are also accompanied with the rise of resistance to different infections and activation of different physio-logical processes. Growth spurts can be twice or more than written here, but those spurts are usually short-timed and often accompanied with the dysfunction of different organs


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hannah B. Elam ◽  
Stephanie M. Perez ◽  
Jennifer J. Donegan ◽  
Daniel J. Lodge

AbstractPost-traumatic stress disorder (PTSD) is a prevalent condition affecting approximately 8% of the United States population and 20% of United States combat veterans. In addition to core symptoms of the disorder, up to 64% of individuals diagnosed with PTSD experience comorbid psychosis. Previous research has demonstrated a positive correlation between symptoms of psychosis and increases in dopamine transmission. We have recently demonstrated projections from the paraventricular nucleus of the thalamus (PVT) to the nucleus accumbens (NAc) can regulate dopamine neuron activity in the ventral tegmental area (VTA). Specifically, inactivation of the PVT leads to a reversal of aberrant dopamine system function and psychosis-like behavior. The PVT receives dense innervation from orexin containing neurons, therefore, targeting orexin receptors may be a novel approach to restore dopamine neuron activity and alleviate PTSD-associated psychosis. In this study, we induced stress-related pathophysiology in male Sprague Dawley rats using an inescapable foot-shock procedure. We observed a significant increase in VTA dopamine neuron population activity, deficits in sensorimotor gating, and hyperresponsivity to psychomotor stimulants. Administration of selective orexin 1 receptor (OX1R) and orexin 2 receptor (OX2R) antagonists (SB334867 and EMPA, respectively) or the FDA-approved, dual-orexin receptor antagonist, Suvorexant, were found to reverse stress-induced increases in dopamine neuron population activity. However, only Suvorexant and SB334867 were able to reverse deficits in behavioral corelates of psychosis. These results suggest that the orexin system may be a novel pharmacological target for the treatment of comorbid psychosis related to PTSD.


Author(s):  
Adam Kraus ◽  
Lukáš Zita

The aim was to assess the internal and external quality of consumer eggs of egg‑laying hens of two selected genotypes depending on their age. All of these hens were kept in enriched cages. There were compared eggs from Hy‑Line Brown and ISA Brown hens at the age from 36 to 64 weeks. In total, 3840 eggs from 300 hens were evaluated. Quality of eggs was determined by their technological value. Statistically significant interactions (P = 0.001) between age and genotype were found in all evaluated parameters except for the yolk colour (P = 0.044), whereas there was not found interaction (P = 0.072) between age and genotype in eggshell strength. The significant effect of hens’ age was found in all evaluated parameters, with the only exception of the yolk colour. The results showed that the average weight of eggs, eggshell, albumen and yolk increased with the age. Also the eggshell proportion, its colour and yolk index values ​​increased, whereas the egg shape index, eggshell thickness and strength, albumen proportion, Haugh units, the albumen and the yolk index decreased. Statistically significant effect of the genotype was found in all evaluated parameters except for the yolk index. When comparing both genotypes, the eggs from ISA Brown hens had a better quality. The trend of deteriorating egg quality with age was confirmed.


Author(s):  
O. Gorobсhenko

The article is devoted to the problem of implementation of intelligent control systems in transport. An important task is to assess the information parameters of the control systems. In the existing works the question of definition of one of the basic parameters of functioning of locomotive control systems - information value of separate signs of a train situation is not considered. This does not make it possible to determine the order of signal processing at the input and assess their contribution to the adoption of a control decision. Moreover, informativeness is a relative value, which is expressed in the different information value of a particular feature for the classification of different train situations. Also, the informativeness of the feature may depend on the type of decisive rules in the classification procedure. The quality of recognition of a train situation in which the locomotive crew is, depends on the quality of the features used by the classification system. The decisive criterion for the informativeness of the features in the problem of pattern recognition is the magnitude of losses from errors. To determine the range of the most informative features of train situations, the method of random search with adaptation was used. The results of the work make it possible to optimize the operation of automated and intelligent train control systems by reducing the amount of calculations and simplifying their algorithm.


eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Stephanie Wendt ◽  
Kim S Strunk ◽  
Jürgen Heinze ◽  
Andreas Roider ◽  
Tomer J Czaczkes

Humans usually assess things not according to their absolute value, but relative to reference points – a main tenant of Prospect Theory. For example, people rate a new salary relative to previous salaries and salaries of their peers, rather than absolute income. We demonstrate a similar effect in an insect: ants expecting to find low-quality food showed higher acceptance of medium-quality food than ants expecting medium quality, and vice versa for high expectations. Further experiments demonstrate that these contrast effects arise from cognitive rather than mere sensory or pre-cognitive perceptual causes. Social information gained inside the nest can also serve as a reference point: the quality of food received from other ants affected the perceived value of food found later. Value judgement is a key element in decision making, and thus relative value perception strongly influences which option is chosen and ultimately how all animals make decisions.


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