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1682. Adaptability of students with different individual and typological peculiarities of vegetative functions regulation
- Creator:
- Tananakina, Tatiana, Lila, Natalya, Ivasenko, Anzhelika, Bolgov, Dmitrij, Mavrich, Svetlana, and Modna, Yuliya
- Format:
- electronic, electronic resource, remote, and elektronický zdroj
- Type:
- model:article, article, Text, hodnotící studie, and TEXT
- Subject:
- adaptace fyziologická, autonomní nervový systém--fyziologie, fyziologické jevy, srdeční frekvence--fyziologie, časná diagnóza, hodnocení rizik, mladiství, dospělí, ženské pohlaví, lidé, mužské pohlaví, studenti, and výchova, vzdělávání
- Language:
- English
- Description:
- In the last decade the health of young people in Ukraine as well as in many other countries of the world significantly deteriorated according to the results of screening tests. Because of this the main task of prophylactic medicine is development and introduction of new methods of early diagnostics of diseases. The aim of the work to assess the peculiarities of adaptation of students with different types of vegetative regulation. Material and methods: 415 second year students of Lugansk State Medical University were tested. The mechanisms of physiological functions of the body regulation were assessed by registration of cardiac rhythm variability (CRV). Analysis of CRV was performed by three methods: statistical, geometrical, and spectral analysis. The express method proposed by Shlyk, N.I. (2009) was later used to determine the prevailing type of vegetative regulation. To assess adaptability the method of R.M. Baevskij (1979) was used. Results: In the result of investigation 4 types of functional states of regulatory systems were determined: I type 295 (71 %) of tested, II in 14 (3 %), III in 96 (23 %) and IV only in 10 (2%). I type of functional state of regulatory systems in the wakeful state at rest was characterized by moderate prevalence of central regulation of heart rhythm (MPCR), decreased activity of autonomic regulation. It was noticed that some of the parameters of CRV (like RR, SDNN, RMSSD and pNN50) which characterize autonomic regulation, were statistically lowere (р≤0.01) compared to type III, and some (like AMo and SI) higher, in both female and male students. Summarized spectrum capacity and components of its wave structure (HF, LF, VLF) which characterize central regulation were statistically significantly lower (р≤0.01) for the I type of regulation compared to the III one which is characterized by moderate prevalence of autonomic regulation of the heart rhythm. In female students with type I autonomic regulation compared to male students such CRV parameters as RR and AМo were statistically significantly lower (р≤0.05), while the parameters of total potency (TP) and high frequency waves (HF) were higher (р≤0.05), which could point to more centralized heart rhythm regulation in male compared to female. The evaluation of regulatory systems overstress allowed to determine the state of adaptation and risk of overstress or breakdown in students with different types of autonomic regulation. Conclusions: Thus, evaluation of adaptation state in students with different types of autonomic regulation allows to characterize the current functional state and uncover the risk of disease development., Tatiana Tananakina, Natalya Lila, Anzhelika Ivasenko, Dmitrij Bolgov, Svetlana Mavrich, Yuliya Modna, and Literatura
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1683. Adaptation of the heart to hypertension is associated with maladaptive gap junction connexin-43 remodeling
- Creator:
- Marcela Fialová, Katarína Dlugošová, Ľudmila Okruhlicová, Kristek, F., Manoach, M., and Narcisa Tribulová
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, hypertenze, srdeční arytmie, physiology, hypertension, cardiac arrhythmia, gap junction remodeling, connexin-43, malignant arrhythmias, 14, and 612
- Language:
- English
- Description:
- We hypothesized that hypertension-related myocardial remodeling characterized by hypertrophy and fibrosis might be accompanied by cell-to-cell gap junction alterations that may account for increased arrhythmogenesis. Intercellular junctions and expression of gap junction protein connexin-43 were analyzed in rat heart tissues from both spontaneous (SHR) and L-NAME model of hypertension. Isolated heart preparation was used to examine susceptibility of the heart to lethal ventricular fibrillation induced by low potassium perfusion. Ultrastructure observation revealed enhanced neoformation of side-to-side type while internalization of end-to-end type (intercalated disc-related) of gap junctions prevailed in the myocardium of rats suffering from either spontaneous or L-NAME-induced hypertension. In parallel, immunolabeling showed increased number of connexin-43 positive gap junctions in lateral cell membrane surfaces, particularly in SHR. Besides, focal loss of immunopositive signal was observed more frequently in hearts of rats treated with L-NAME. There was a significantly higher incidence of hypokalemia-induced ventricular fibrillation in hypertensive compared to normotensive rat hearts. We conclude that adaptation of the heart to hypertension-induced mechanical overload results in maladaptive gap junction remodeling that consequently promotes development of fatal arrhythmias., M. Fialová, K. Dlugošová, L. Okrouhlicová, F. Kristek, M. Manoach, N. Tribulová., and Obsahuje bibliografii a biblioigrafické údaje
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1684. Adaptations of Coccinella magnifica, a myrmecophilous coccinellid to aggression by wood ants (Formica rufa group). II.. Larval behaviour, and ladybird oviposition location1
- Creator:
- Sloggett, John J. and Majerus, Michael E.N.
- Type:
- article, model:article, and TEXT
- Subject:
- occinella magnifica, Coccinella septempunctata, Formica rufa, ant-tended aphids, myrmecophily, and oviposition
- Language:
- English
- Description:
- Like adults, larvae of the myrmecophilous ladybird Coccinella magnifica are rarely attacked by Formica rufa ants on foraging trails, but more often attacked on ant-tended aphid colonies. Larvae of the non-myrmecophile Coccinella septempunctata, to which C. magnifica was compared, were more readily attacked by ants in both situations. To avoid or counter ant aggression when foraging for aphids, C. magnifica larvae exhibit three main tactics: they may feed on un- or non-tended aphids; when feeding on tended colonies they often carry prey away, minimising time spent there; and if attacked, they use limited chemical defence. No novel behaviours were found in C. magnifica larvae, not occurring to some extent in C. septempunctata. Coccinella magnifica eggs were laid distant to ant-tended aphids, although closer to un- or non-tended aphids.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1685. Adaptive control of uncertain nonholonomic systems in finite time
- Creator:
- Wang, Jiankui, Zhang, Guoshan, and Li, Hongyi
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- finite-time convergence, parameter uncertainty, adaptive control, and nonholonomic systems
- Language:
- English
- Description:
- In this paper, the finite-time stabilization problem of chained form systems with parametric uncertainties is investigated. A novel switching control strategy is proposed for adaptive finite-time control design with the help of Lyapunov-based method and time-rescaling technique. With the proposed control law, the uncertain closed-loop system under consideration is finite-time stable within a given settling time. An illustrative example is also given to show the effectiveness of the proposed controller.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1686. Adaptive finite-time synchronization of cross-strict feedback hyperchaotic systems with parameter uncertainties
- Creator:
- Li, Hai-Yan, Hu, Yun-An, and Wang, Rui-Qui
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- finite-time synchronization, cross-strict feedback hyperachaotic system, backstepping, and adaptive control
- Language:
- English
- Description:
- This paper is concerned with the finite-time synchronization problem for a class of cross-strict feedback underactuated hyperchaotic systems. Using finite-time control and backstepping control approaches, a new robust adaptive synchronization scheme is proposed to make the synchronization errors of the systems with parameter uncertainties zero in a finite time. Appropriate adaptive laws are derived to deal with the unknown parameters of the systems. The proposed method can be applied to a variety of chaotic systems which can be described by the so-called cross-strict feedback systems. Numerical simulations are given to demonstrate the efficiency of the proposed control scheme.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1687. Adaptive neuro-fuzzy inference system with second order Sugeno consequents
- Creator:
- Alata, Mohanad and Moaqet, Hisham
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- ANFIS, Substractive clustering, Sugeno fuzzy inference systems, and fuzzy modeling
- Language:
- English
- Description:
- Adaptive Neuro-Fuzzy Inference System (ANFIS) with first order Sugeno consequent is used widely in modeling applications. Though it has the advantage of giving good modeling results in many cases, it is not capable of modeling highly non-linear systems with high accuracy. In this paper, an efficient way for using ANFIS with Sugeno second order consequents is presented. Better approximation capability of Sugeno second order consequents compared to lower order Sugeno consequents is shown. Subtractive clustering is used to determine the number and type of membership functions. A hybrid-learning algorithm that combines the gradient descent method and the least squares estimate is then used to update the parameters of the proposed Second Order Sugeno-ANFIS (SOS-ANFIS). Simulation of the proposed SOS-ANFIS for two examples shows better results than that of lower order Sugeno consequents. The proposed SOS-ANFIS shows better initial error, better convergence, quicker convergence and much better final error value.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1688. Adaptive output feedback stabilization for nonlinear systems with unknown polynomial-of-output growth rate and sensor uncertainty
- Creator:
- Shen, Yanjun and Lin, Lei
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- adaptive stabilization, polynomial-of-output growth rate, measurement sensitivity, output feedback, and observer
- Language:
- English
- Description:
- In this paper, the problem of adaptive output feedback stabilization is investigated for a class of nonlinear systems with sensor uncertainty in measured output and a growth rate of polynomial-of-output multiplying an unknown constant in the nonlinear terms. By developing a dual-domination approach, an adaptive observer and an output feedback controller are designed to stabilize the nonlinear system by directly utilizing the measured output with uncertainty. Besides, two types of extension are made such that the proposed methods of adaptive output feedback stabilization can be applied for nonlinear systems with a large range of sensor uncertainty. Finally, numerical simulations are provided to illustrate the correctness of the theoretical results.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1689. Adaptive preferential selection of female coccinellid hosts by the parasitoid wasp Dinocampus coccinellae (Hymenoptera: Braconidae)
- Creator:
- Davis, Dexter S., Stewart, Sarah L. , Manica, Andrea, and Majerus, Michael E.N.
- Type:
- article, model:article, and TEXT
- Subject:
- Parasitoidism, host discrimination, host sex, Dinocampus coccinellae, Braconidae, Coccinella septempunctata, and Coccinellidae
- Language:
- English
- Description:
- Females of the parasitoid wasp Dinocampus coccinellae are known to parasitise both male and female coccinellid hosts. It is suggested that female hosts provide more resources for developing wasp larvae because they tend to be larger than male hosts, and female coccinellids have a much greater food intake than males. Thus the wasp's lifetime reproductive success should be increased by ovipositing preferentially in female rather than male hosts when given a choice. Laboratory experiments, using Coccinella septempunctata as a host, show that such a preference does exist. Wasps preferentially oviposit in females, and this preference is not simply a result of the larger mean size of females compared to males. These results corroborate higher rates of prevalence in female compared to male hosts reported previously.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1690. Adaptive preferential selection of young coccinellid hosts by the parasitoid wasp Dinocampus coccinellae (Hymenoptera: Braconidae)
- Creator:
- Majerus, Michael E. N., Geoghegan, Irene E., and Majerus, Tamsin M. O.
- Type:
- article, model:article, and TEXT
- Subject:
- parasitoid, host selection, host discrimination, Dinocampus coccinellae, Braconidae, Coccinella septempunctata, and Coccinellidae
- Language:
- English
- Description:
- Dinocampus coccinellae females which eclose in mid-summer have the opportunity to oviposit in overwintered or in newly eclosed coccinellid hosts. Given the short further longevity of overwintered hosts, offspring fitness would be increased by ovipositing preferentially in young hosts. Laboratory choice tests show that female D. coccinellae do exhibit such a preference.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public