scholarly journals Sponge symbiosis is facilitated by adaptive evolution of larval sensory and attachment structures in barnacles

2020 ◽  
Vol 287 (1927) ◽  
pp. 20200300 ◽  
Author(s):  
Meng-Chen Yu ◽  
Niklas Dreyer ◽  
Gregory Aleksandrovich Kolbasov ◽  
Jens Thorvald Høeg ◽  
Benny Kwok Kan Chan
Keyword(s):  
Coral Reefs ◽  
Larval Settlement ◽  
Interspecific Variation ◽  
Marine Systems ◽  
Symbiotic Relationships ◽  
Larval Attachment ◽  
Attachment Structures ◽  
The Stability ◽  
High Level ◽  
High Degree

Symbiotic relations and range of host usage are prominent in coral reefs and crucial to the stability of such systems. In order to explain how symbiotic relations are established and evolve, we used sponge-associated barnacles to ask three questions. (1) Does larval settlement on sponge hosts require novel adaptations facilitating symbiosis? (2) How do larvae settle and start life on their hosts? (3) How has this remarkable symbiotic lifestyle involving many barnacle species evolved? We found that the larvae (cyprids) of sponge-associated barnacles show a remarkably high level of interspecific variation compared with other barnacles. We document that variation in larval attachment devices are specifically related to properties of the surface on which they attach and metamorphose. Mapping of the larval and sponge surface features onto a molecular-based phylogeny showed that sponge symbiosis evolved separately at least three times within barnacles, with the same adaptive features being found in all larvae irrespective of phylogenetic relatedness. Furthermore, the metamorphosis of two species proceeded very differently, with one species remaining superficially on the host and developing a set of white calcareous structures, the other embedding itself into the live host tissue almost immediately after settlement. We argue that such a high degree of evolutionary flexibility of barnacle larvae played an important role in the successful evolution of complex symbiotic relationships in both coral reefs and other marine systems.

scholarly journals Geometric control of quadrotor UAVs using integral backstepping

2021 ◽  
Vol 22 (1) ◽  
pp. 53
Author(s):  
Ali Bouchaib ◽  
Rachid Taleb ◽  
Ahmed Massoum ◽  
Saad Mekhilef
Keyword(s):  
Control System ◽  
Dynamic Model ◽  
Level Control ◽  
Control Laws ◽  
System Nonlinearity ◽  
System Robustness ◽  
The Stability ◽  
High Level ◽  
High Degree ◽  
Quaternion Representation

The traditional quadcopter control systems should deal with two common problems. Namely, the singularities related to the inverse kinematics and the ambiguity linked to the quaternion representation of the dynamic model. Moreover, the stability problem due to the system nonlinearity and high degree of coupling. This paper provides a solution to the two issues by employing a geometrical integral-backstepping control system. The integral terms were added to improve system ability to track desired trajectories. The high-level control laws are considered as a virtual control and transmitted to the low-level to track the high-level commands. The proposed control system along with the quadcopter dynamic model were expressed in the special Euclidean group SE(3). Finally, the control system robustness against mismatching parameters was studied while tracking various paths.

DIAGNOSTICS OF THE STATE OF FINANCIAL SECURITY OF UKRAINE

2018 ◽  
pp. 12-18 ◽  
Author(s):  
Iryna Petrivna Mihus ◽  
Liudmila Mykolayivna Akimova ◽  
Elena Anatolievna Harnyk
Keyword(s):  
Economic Security ◽  
The State ◽  
Financial Security ◽  
Economic Relations ◽  
External Threats ◽  
Complex Process ◽  
The Stability ◽  
Security Indicators ◽  
High Level ◽  
High Degree

Urgency of the research. The transition to the market in Ukraine led to changes in the sphere of economic relations, which are characterized by a high level of instability. Signifi-cant changes that have occurred in recent years have also created new threats to the domestic economy, necessitating the diagnosis of Ukraine's financial security. Target setting. The welfare of each state primarily de-pends on the stability of its financial system, which is provid-ed through the timely diagnosis of its threats and response to them. Actual scientific researches and issues analysis. The issues of financial security of the nation, as an economic component, the principles of the formation of a system for ensuring financial security were revealed in the works of domestic and foreign scientists, namely in the works of A. Baranovsky, V. Geyets, M. Yermoshenko, J. Zhalilo, B. Karpinsky. A. Sukhorukov, A. Shevchenko and others. Uninvestigated parts of general matters defining. In the conditions of cyclical economic fluctuations, which are characterized by a high degree of uncertainty, it is of acute necessity to diagnose the financial security as a component of the state's economic security. The research objective. The purpose of the article is to conduct a diagnosis of Ukraine's financial security and identi-fy the threats that affect it. The statement of basic materials. The article analyzes both the dynamics of integral indicators of the components of financial security by the methodology of the Ministry of Economy of Ukraine for 2013 – 2017 and the dynamics of financial security indicators by the methodology of the Na-tional Institute of International Security Problems of Ukraine from 2013 to 2017, as well as distinguishes their shortcom-ings. There is proposed a system of measures to increase the level of financial security of the enterprises in Ukraine. Conclusions. Diagnostics of the level of financial security is a complex process of identifying, analyzing, eliminating and forecasting the emergence of internal and external threats to the state. Diagnosis of the components of financial security is the basis for developing a set of measures to counter threats and improve the level of protection of Ukraine.

scholarly journals Lifeworld Stability in Qualified Athletes with Various Levels of Professional Success: Comparative Analysis

2019 ◽  
Vol 21 (1) ◽  
pp. 87-100
Author(s):  
I. O. Loginova ◽  
M. S. Sevost’yanova
Keyword(s):  
Comparative Analysis ◽  
Highly Qualified ◽  
Actual Problem ◽  
Sports Teams ◽  
Psychological Conditions ◽  
Professional Success ◽  
Professional Longevity ◽  
The Stability ◽  
High Level ◽  
High Degree

The article continues a series of studies devoted to the actual problem of increasing sports effectiveness and the growth of  professional longevity of highly qualified athletes – members of  Russian national sports teams. Not contradicting the methodological  foundations of research of sports activities, the authors propose a  solution to the problem of psychological and pedagogical support of  professional success in sports of higher achievements. The research  is based on the systemic anthropological psychology and the theory  of human self-realization. The subject of this study is the  peculiarities of the stability of the lifeworld in athletes with various  levels of professional success. The paper features a comparative  analysis, the results of which clearly illustrate the specific features of the manifestation of the lifeworld stability in athletes with various levels of professional success. It was empirically proved that  the high degree of life-world stability and the constructive nature of  its manifestation are the psychological conditions for the optimal  combination of processes of achieving high athletic results and  maintaining a high level of mental adaptation. It determines the  sustainability of the lifeworld as a systemic psychological  characteristic responsible for the effective professionalization in the  sport of higher achievements. This allows the authors to conclude  that the program of psychological and pedagogical support  introduced in this paper will probably improve sports effectiveness  and mental adaptation of athletes, contributing to the growth of their professional longevity.

ANTICYTOKINE ACTIVITY OF THE PROTOZOA BLASTOCYSTIS SPP

2020 ◽  
pp. 44-48
Author(s):  
Bugero N.V. ◽  
Ilyina N.A. ◽  
Aleksandrova S.M.
Keyword(s):  
Gastrointestinal Tract ◽  
Gastrointestinal Diseases ◽  
Control Group ◽  
Ulcer Disease ◽  
Cytokine Balance ◽  
High Prevalence ◽  
Blastocystis Spp ◽  
High Level ◽  
Eukaryotic Organisms ◽  
High Degree

In addition to the classical pathogens, which are well understood and well identified, new pathogens with the potential to spread epidemiologically are being identified. Some of these little-known organisms are the simplest Blastocystis spp. blastocystostosis. The clinical significance of Blastocystis spp. and its pathogenicity are still under discussion. This parasite belongs to a group of single-celled eukaryotic organisms living in the colon of the human intestine. Blastocystis spp. is known to be found both in people with reduced immune status and in individuals without any clinical manifestation. It has been established that a sufficiently high degree of invasiveness is observed in persons with gastrointestinal tract diseases, dermatosis, allergic reactions, in patients with carriers of the human immunodeficiency virus, etc. Possessing persistence factors, protozoa blastocysts contribute to the inactivation of host defensive mechanisms, providing a stable anthogonistic effect. In recent years, many works have been devoted to the characteristics of the persistent properties of Blastocystis spr., however, individual properties of blastocysts, in particular, anticytokine activity (ACA), have not yet been studied. In this regard, the work studied the anticytokine activity of microorganisms isolated from healthy subjects and patients with gastrointestinal tract diseases. A high prevalence of the studied characteristic in the subjects was shown. The expression of anticytokine activity in the obtained isolates of blastocysts was the highest in the group of persons with gastric ulcer disease, which decreased in the order of duodenal ulcer, chronic cholecystitis, chronic gastritis, etc. The data obtained in this work on the high level of ACA expression in blastocyst isolates obtained from individuals with gastrointestinal diseases as compared with the control group enables to conclude that their exometabolites may influence the local cytokine balance [1], which supports the inflammatory process.

METHODS FOR RESTORING WOLVES OF ROLLING PRODUCTION

2020 ◽  
Vol 4 (141) ◽  
pp. 114-122
Author(s):  
DAR’YA LEBEDEVA ◽  
◽  
ANNA KARPUNICHEVA
Keyword(s):  
Thermal Effects ◽  
Machine Building ◽  
Research Purpose ◽  
Technical Literature ◽  
Production Methods ◽  
Advantages And Disadvantages ◽  
Rolling Production ◽  
Machine Parts ◽  
The Stability ◽  
High Degree

Large forces and significant thermal effects are created on the rolls when rolling sheets. The higher the stability of the rolls, the less downtime during their rerolling and higher productivity. (Research purpose) The research purpose is in analyzing the ways of restoring rolls and choose the most appropriate method for restoring these parts. (Materials and methods) The article presents the analysis of the scientific and technical literature on the topic of rolling production, methods for restoring large-sized machine parts of machine-building and metallurgical industries that work in difficult conditions and are subject to a high degree of wear. Authors try to solve the problem by means of comparative and logical analysis based on theoretical and empirical methods of scientific research. (Results and discussion) The article presents two groups of methods for restoring rolled rolls: banding and surfacing the working layer of the roll. Authors have analyzed each method in terms of technology, equipment, and feasibility. The article presents the advantages and disadvantages of the methods under consideration. (Conclusions) The most acceptable way to restore parts with a high degree of wear is surfacing. It is most efficient to apply submerged surfacing using an additional hot additive. Such surfacing, despite some complication of the equipment design, allows to deposit the metal on the roll with low heat input and in most cases in one pass. Surfacing using an additional hot additive allows to increase the productivity of the process by up to 250 percent while reducing the penetration depth by 2-3 times and saving energy by up to 40 percent.

Radiation Effects on Hollandite Ceramics developed for Radioactive Cesium Immobilization

2003 ◽  
Vol 792 ◽  
Author(s):  
V. Aubin ◽  
D. Caurant ◽  
D. Gourier ◽  
N. Baffier ◽  
S. Esnouf ◽  
...  
Keyword(s):  
Radiation Effects ◽  
Liquid Waste ◽  
Fission Products ◽  
Radioactive Cesium ◽  
Radioactive Liquid Waste ◽  
Epr Spectrum ◽  
Paramagnetic Resonance ◽  
Γ Radiation ◽  
The Stability ◽  
High Level

ABSTRACTProgress on separating the long-lived fission products from the high level radioactive liquid waste (HLW) has led to the development of specific host matrices, notably for the immobilization of cesium. Hollandite (nominally BaAl2Ti6O16), one of the main phases constituting Synroc, receives renewed interest as specific Cs-host wasteform. The radioactive cesium isotopes consist of short-lived Cs and Cs of high activities and Cs with long lifetime, all decaying according to Cs+→Ba2++e- (β) + γ. Therefore, Cs-host forms must be both heat and (β,γ)-radiation resistant. The purpose of this study is to estimate the stability of single phase hollandite under external β and γ radiation, simulating the decay of Cs. A hollandite ceramic of simple composition (Ba1.16Al2.32Ti5.68O16) was essentially irradiated by 1 and 2.5 MeV electrons with different fluences to simulate the β particles emitted by cesium. The generation of point defects was then followed by Electron Paramagnetic Resonance (EPR). All these electron irradiations generated defects of the same nature (oxygen centers and Ti3+ ions) but in different proportions varying with electron energy and fluence. The annealing of irradiated samples lead to the disappearance of the latter defects but gave rise to two other types of defects (aggregates of light elements and titanyl ions). It is necessary to heat at relatively high temperature (T=800°C) to recover an EPR spectrum similar to that of the pristine material. The stability of hollandite phase under radioactive cesium irradiation during the waste storage is discussed.

CSim 2

2021 ◽  
Vol 43 (1) ◽  
pp. 1-46
Author(s):  
David Sanan ◽  
Yongwang Zhao ◽  
Shang-Wei Lin ◽  
Liu Yang
Keyword(s):  
Programming Languages ◽  
Concurrent Systems ◽  
Theorem Prover ◽  
Compositional Techniques ◽  
Machine Code ◽  
Top Down ◽  
Hol Theorem Prover ◽  
High Level ◽  
High Degree

To make feasible and scalable the verification of large and complex concurrent systems, it is necessary the use of compositional techniques even at the highest abstraction layers. When focusing on the lowest software abstraction layers, such as the implementation or the machine code, the high level of detail of those layers makes the direct verification of properties very difficult and expensive. It is therefore essential to use techniques allowing to simplify the verification on these layers. One technique to tackle this challenge is top-down verification where by means of simulation properties verified on top layers (representing abstract specifications of a system) are propagated down to the lowest layers (that are an implementation of the top layers). There is no need to say that simulation of concurrent systems implies a greater level of complexity, and having compositional techniques to check simulation between layers is also desirable when seeking for both feasibility and scalability of the refinement verification. In this article, we present CSim 2 a (compositional) rely-guarantee-based framework for the top-down verification of complex concurrent systems in the Isabelle/HOL theorem prover. CSim 2 uses CSimpl, a language with a high degree of expressiveness designed for the specification of concurrent programs. Thanks to its expressibility, CSimpl is able to model many of the features found in real world programming languages like exceptions, assertions, and procedures. CSim 2 provides a framework for the verification of rely-guarantee properties to compositionally reason on CSimpl specifications. Focusing on top-down verification, CSim 2 provides a simulation-based framework for the preservation of CSimpl rely-guarantee properties from specifications to implementations. By using the simulation framework, properties proven on the top layers (abstract specifications) are compositionally propagated down to the lowest layers (source or machine code) in each concurrent component of the system. Finally, we show the usability of CSim 2 by running a case study over two CSimpl specifications of an Arinc-653 communication service. In this case study, we prove a complex property on a specification, and we use CSim 2 to preserve the property on lower abstraction layers.

scholarly journals Computing the Exact Number of Similarity Classes in the Longest Edge Bisection of Tetrahedra

Mathematics ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 1447
Author(s):  
Jose P. Suárez ◽  
Agustín Trujillo ◽  
Tania Moreno
Keyword(s):  
Data Structure ◽  
Stability Condition ◽  
Open Problem ◽  
Integer Arithmetic ◽  
Exact Number ◽  
Similarity Class ◽  
The Stability ◽  
High Level ◽  
The Cost

Showing whether the longest-edge (LE) bisection of tetrahedra meshes degenerates the stability condition or not is still an open problem. Some reasons, in part, are due to the cost for achieving the computation of similarity classes of millions of tetrahedra. We prove the existence of tetrahedra where the LE bisection introduces, at most, 37 similarity classes. This family of new tetrahedra was roughly pointed out by Adler in 1983. However, as far as we know, there has been no evidence confirming its existence. We also introduce a new data structure and algorithm for computing the number of similarity tetrahedral classes based on integer arithmetic, storing only the square of edges. The algorithm lets us perform compact and efficient high-level similarity class computations with a cost that is only dependent on the number of similarity classes.

Addiction and schizophrenia

2000 ◽  
Vol 15 (2) ◽  
pp. 115-122 ◽  
Author(s):  
P. Batel
Keyword(s):  
Epidemiologic Studies ◽  
Self Medication ◽  
Addictive Disorders ◽  
Co Morbidity ◽  
Dependency Type ◽  
Active Research ◽  
Social Environmental ◽  
High Level ◽  
Environmental Hypothesis ◽  
High Degree

SummaryEpidemiologic studies in the general population and those based on the clinical assessment of schizophrenic populations have revealed a high degree of overlap between schizophrenia and addictive disorders. The abuse of psychoactive substances (including alcohol) throughout life is so frequent (50%) that the possibility of a specific link inevitably arises. Various hypotheses have been suggested to explain the high co-morbidity between schizophrenia and addiction: 1) The social-environmental hypothesis has been developed but studies have provided poor evidence to validate it. 2) The possible shared biological vulnerability between schizophrenia and addictions led researchers to explore common genetic determinants and study the involvement of the dopaminergic and opioid systems in the aetiology of both schizophrenia and the abuse of and dependence on psychoactive drugs. 3) Finally, the theory of self-medication suggests that schizophrenics may be attempting to counter the deficit linked to their disorders by using the substances they take or their dependency-type behaviour to cope with their emotional problems. The clinical profile of schizophrenic addicts does seem to display some distinctive features, such as the high level of depressive co-morbidity, very high nicotine and alcohol dependence, with a very poor prognosis. These patients are difficult to manage; the possibility of pharmacologic interactions between the substances they are taking and neuroleptic medication calls for prudence, and their compliance is also poor. Addictive disorders in schizophrenics are currently a topic of active research intended to lead to identifying specific treatments. The early identification of addictive disorders in schizophrenics should make it possible to limit their development and improve the prognosis.

Features of pubertal patients with schizophrenia neurocognitive profile

2017 ◽  
Vol 41 (S1) ◽  
pp. S430-S431
Author(s):  
Y. Barylnik ◽  
S. Pakhomova ◽  
D. Samoylova ◽  
J. Abrosimova ◽  
E. Kolesnichenko ◽  
...  
Keyword(s):  
Stability Index ◽  
Neurocognitive Disorders ◽  
Motor Speed ◽  
Structuring Element ◽  
Test Part ◽  
Psychic Disorders ◽  
Competing Interest ◽  
Neurocognitive Profile ◽  
The Stability ◽  
High Level

Identifying the patterns of neurocognitive disorders in pubertal schizophrenia is actual.MethodsBenton Test of visual retention, methods of forward and reverse bills, Bourdon correction sample, Wechsler's subtests (subtest 11 – “Encryption”, subtest 12 – “Labyrinths” 1, 2, 3, 4, 5), Trail Creating a Test Part A.ResultsAll patients were divided into 3 groups. The first group (schizophrenia) and second group (other psychic disorders) showed the worst results than healthy subjects. Qualitative analysis of the “Benton Test” results showed similar variations of difficulty and types of errors in the subjects of the first and second groups – ignoring the number of the figure sides, as well as difficulties in the structuring element of the image corners. The “Methods of forward and reverse bills” demonstrated the fatigue and attention instability. “Bourdon test” showed a high level of the stability index (K = 0.09). Wechsler's subtest “Encryption B” obtained poor results, indicating a pathological decrease in visual-motor speed. During the subtest “Labyrinths 1, 2, 3, 4, 5” the subjects of first and second groups exceeded the allowable time limit, but the first group of schizophrenia patients allowed more blunders during pubertal study (ignored the walls of the maze, torn pencil despite the given instructions). The test groups 1 and 2 while passing “Trail Creating a Test Part A” have shown good results – job data did not cause difficulties and carried out in accordance with the specified instructions.ConclusionsNeurocognitive disorders allow to confirm the presence of morphological and functional brain changes when endogenous mental illness occurs.Disclosure of interestThe authors have not supplied their declaration of competing interest.

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