In this paper, a novel two-level framework was proposed and applied to solve the output average consensus problem over heterogeneous multi-agent systems. This approach is mainly based on the recent technique of system abstraction. For given multi-agent systems, we first constructed their abstractions as the upper level and solved their average consensus problem by leveraging well-known results for single integrators. Then the control protocols for physical agents in the lower level were synthesized in a hierarchical way by embedding the designed law for abstractions into an interface between two levels. In this way, the complexity coming from heterogeneous dynamics of agents is totally decoupled from that of the coordination task and the communication topologies. An example was given to show its effectiveness.
In this paper, we consider an output consensus problem for a general class of nonlinear multi-agent systems without a prior knowledge of the agents' control directions. Two distributed Nussbaum-type control laws are proposed to solve the leaderless and leader-following adaptive consensus for heterogeneous multiple agents. Examples and simulations are given to verify their effectiveness.
This paper is concerned with the problem of global state regulation by output feedback for large-scale uncertain nonlinear systems with time delays in the states and inputs. The systems are assumed to be bounded by a more general form than a class of feedforward systems satisfying a linear growth condition in the unmeasurable states multiplying by unknown growth rates and continuous functions of the inputs or delayed inputs. Using the dynamic gain scaling technique and choosing the appropriate Lyapunov-Krasovskii functionals, we explicitly construct the universal output feedback controllers such that all the states of the closed-loop system are globally bounded and the states of large-scale uncertain systems converge to zero.
According to several studies, women with Crohn's disease (CD) had reduced fertility, which is mostly due to voluntary decisions and reduced ovarian reserve. In our study, we aimed to compare reproductive health parameters (RHP), previous pregnancy complications and outcomes, and ovarian reserve (OR) assessed by the anti-Mullerian hormone (AMH) in CD patients with healthy controls. In CD patients, we also compared OR according to disease phenotypes. Consecutive pre-menopausal women with CD from two IBD centers were included. The control group consisted of age and BMI-matched healthy controls. We used a questionnaire that included RHP, CD phenotype, and CD activity. Serum AMH was assessed by the Elecsys AMH plus essay. We enrolled 50 patients and 56 controls with a median age of 31 years. All CD patients were in clinical remission. We observed no difference in RHP or AMH (median 2.6 vs. 2.1 ug/l, p = 0.98), or the proportion of low OR (AMH<1,77, 38 vs. 41.1 %, p=0.84). The slope of age-related decrease did not differ between the groups. The subgroup of CD patients after surgery and those older than 30 years with CD for >5years had a steeper decrease in AMH (slope -0.12 vs. -0.29, p = 0.04 and - 0.31 vs. -0.2, p = 0.029). In a multivariate analysis, age was the single independent predictor of low OR (OR=1.25). In women with Crohn’s disease, once the disease activity is under control, the reproductive health and ovarian reserve do not substantially differ from healthy controls., Tomáš Koller, Jana Kollerová, Tibor Hlavatý, Barbora Kadlečková, Juraj Payer., and Obsahuje bibliografii
This study aimed at examining the secretion activity of steroid hormones progesterone and 17β-estradiol by porcine ovarian granulosa cells after addition of green tea extract. Granulosa cells were incubated with green tea extract (at doses of 0.01, 0.1, 1, 10 and 100 μg.ml-1). Another set of cells were incubated with green tea extract at the above doses along with additional supplementation of follicle stimulating hormone (FSH) at 10 μg.ml-1. Release of hormones by granulosa cells was assessed by EIA after 24 h exposure. Secretion of steroid hormones was not affected either by green tea extract alone or after FSH supplementation with green tea extract. Results indicate that ovarian steroidogenesis is not affected by green tea under conditions used in the experiment.
Beneficial effects of Sambucus nigra L. (black elder) as a traditional medicine have been associated with the phytoconstituents including polyphenols, terpenes and lectins. Various antioxidant rich natural products have also been implicated with improvement of reproductive health and fertility, however, the effect of Sambucus nigra on the ovarian cell functions has not been investigated yet. The objectives of the present study were to screen the polyphenols in the elderflower and elderberry extracts, and to examine the secretion activity of steroid hormones 17β-estradiol and progesterone by human ovarian granulosa cells HGL5 after supplementation of the extracts at a concentration range of 12.5 to 100 µg.ml-1 . Qualitative as well as quantitative screening of polyphenols by high-performance liquid chromatography with diode-array detector (HPLC-DAD) analysis revealed rutin to be the most abundant polyphenol in both elderflower and elderberry extracts. In culture, neither elderflower nor elderberry extract caused any significant impact (p>0.05) in cell viability as studied by AlamarBlue assay in comparison to control. However, a dosedependent stimulation of 17β-estradiol release was detected by ELISA after supplementation of elderflower (at 50 µg.ml-1 ; p<0.01) and elderberry (at 100 µg.ml-1 ; p<0.05) extracts at higher doses used in the study. On the other hand, both elderflower and elderberry extracts stimulated the secretion of progesterone by HGL5 cells at a lower dose (12.5 µg.ml-1 ; p<0.05), as compared to control. Therefore, elderflower and elderberry extracts may have the potential to regulate steroidogenesis in ovarian cells., Simona Baldovska, Shubhadeep Roychoudhury, Marek Bandik, Michal Mihal, Erika Mnahoncakova, Julius Arvay, Ales Pavlik, Petr Slama, Adriana Kolesarova., and Obsahuje bibliografii
Ovaries of Puto superbus and Ceroputo pilosellae are composed of numerous short telotrophic ovarioles that are arranged around the distal part of the lateral oviduct. An individual ovariole consists of a distal trophic chamber (= tropharium) and proximal vitellarium. The tropharia enclose individual trophocytes (= nurse cells) and early previtellogenic oocytes termed arrested oocytes. A single oocyte develops in each vitellarium. Analysis of serial sections has shown that ovarioles of P. superbus contain from 16 to 51 germ cells (13–43 trophocytes, 2–7 arrested oocytes, 1 developing oocyte) while those of C. pilosellae from only 8 to 10 germ cells (5–7 trophocytes, 0–2 arrested oocytes, 1 developing oocyte). The classification and phylogeny of scale insects are discussed taking into consideration the results of this study., Anna Michalik ... [et al.]., and Obsahuje seznam literatury