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9052. Singular spectrum analysis for heterogeneous time series by taking its formal errors into account
- Creator:
- Wang , Fengwei , Shen, Yunzhong , Li, Weiwei , and Chen, Qiujie
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- time series analysis, singular spectrum analysis, stabilizing weights, and formal error
- Language:
- English
- Description:
- Since the formal errors of many geodetic time series are also available, this paper proposes a new singular spectrum analysis (SSA) approach with stabilizing weights (SSAW) by taking the formal errors into account, where the weight of time series data is constructed based on the ratio of formal error to signal power spectrum. The formulae of the proposed SSAW are derived in detail and then used to process the real Global Mean Sea Level (GMSL) time series compared to the traditional SSA. When the first 10 principal components are used to fit the GMSL time series, the fitting errors of the SSAW and traditional SSA are 4.80 mm and 5.14 mm, with the reduction of 6.61 %. According to the 500 simulations based on the reconstructed signals and formal errors of GMSL time series, the mean root mean squared errors and mean absolute errors of reconstructed signals using the SSAW relative to traditional SSA are reduced from 2.18 mm to 1.66 mm and 1.67 mm to 1.34 mm, respectively. Therefore, if the formal errors of a noisy time series given, the proposed SSAW approach is suggested to analyze this time series.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9053. Sirtuin 1 modulation in rat model of acetaminophen-induced hepatotoxicity
- Creator:
- Wojnarová, L., Nikolína Kutinová-Canová, Hassan Farghali, and Tomáš Kučera
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, játra, physiology, liver, SIRT1, resveratrol, acetaminophen, CAY10591, 14, and 612
- Language:
- English
- Description:
- Sirtuin 1 (SIRT1) is involved in important biological processes such as energy metabolism and regulatory functions of the cell cycle, apoptosis, and inflammation. Our previous studies have shown hepatoprotective effect of polyphenolic compound resveratrol, which is also an activator of SIRT1. Therefore, the aim of our present study was to clarify the role of SIRT1 in process of hepatoprotection in animal model of drug-induced liver damage. Male Wistar rats were used for both in vivo and in vitro studies. Hepatotoxicity was induced by single dose of acetaminophen (APAP). Some rats and hepatocytes were treated by resveratrol or synthetic selective activator of sirtuin 1 (CAY10591). The degree of hepatotoxicity, the activity and expression of the SIRT1 were determined by biochemical, histological and molecular-biological assessments of gained samples (plasma, liver tissue, culture media and hepatocytes). Resveratrol and CAY attenuated APAP-induced hepatotoxicity in vivo and in vitro. Moreover, both drugs enhanced APAPreduced SIRT1 activity. Our results show that modulation of the SIRT1 activity plays a role in hepatoprotection. Synthetic activators of SIRT1 would help in understanding the role of SIRT1 and are therefore a major boost towards the search for specific treatment of liver disease., L. Wojnarová, N. Kutinová Canová, H. Farghali, T. Kučera., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9054. Site velocities from long-term epoch GPS observations - case study: Central Europe regional geodynamic project 1994-2005
- Creator:
- Ján Hefty and Ľubomíra Gerhátová
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, GPS sítě, GPS netwoks, epoch GPS network, Central Europe Geodynamic Reference Network, site velocities - horizontal and vertical, intraplate velocity field in Central Europe, 7, and 551
- Language:
- English
- Description:
- Series of repeated epoch-wise GPS campaigns performed in Central European region are used for estimation of site velocities. The main features of campaign processing and combination of network solutions are outlined. The velocities obtained from epoch observations within the Central Europe Regional Geodynamic Project covering the 11-year time span are compared at some sites with velocities derived from permenent GPS observations., Ján Hefty and Ľubomíra Gerhátová., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9055. Six new species of coccidia (Apicomplexa: Eimeriidae) from endangered Phelsuma spp. geckoes (Sauria: Gekkonidae) of the Black River Gorges National Park, Mauritius
- Creator:
- Daszak, Peter, Ball, Stanley J., Jones, Carl G., Streicker, Daniel G., and Snow, Keith R.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Coccidia, Apicomplexa, Eimeriidae, Eimeria, Isospora, Reptilia, Sauria, Gekkonidae, Phelsuma, and Mauritius
- Language:
- English
- Description:
- Six new species of coccidia are described from endangered Phelsuma spp. geckoes (Sauria: Gekkonidae) endemic to Mauritius, Indian Ocean. Five new species (3 Eimeria and 2 Isospora species) are described from Phelsuma rosagularis Vinson et Vinson; all lack a micropyle and an oocyst residuum, and all have a sporocyst residuum. Oocysts of Eimeria swinnertonae sp. n. are ellipsoidal, 22.2 × 17.8 (20.8-24.8 × 16.8-18.4) μm; SI 1.25; polar granule absent. Sporocysts are ellipsoidal, 8.8 × 7.0 (8.0-9.6 × 6.4-8.0) μm; SI 1.3; Stieda body absent. Oocysts of Eimeria stebbinsi sp. n. are ellipsoidal, 17.4 × 11.7 (16.0-19.2 × 11.2-12.8) μm; SI 1.5; polar granules present. Sporocysts are elongate-ellipsoidal, 7.7 × 4.0 (7.2-8.0 × 3.2-5.6) μm; SI 1.9; Stieda body present. Oocysts of Eimeria raleighi sp. n. are spheroidal to sub-spheroidal, 17.0 × 15.5 (16.0-19.2 × 14.4-16.8) μm; SI 1.1; polar granule present. Sporocysts are sub-spheroidal, 7.8 × 6.6 (7.2-8.0 × 6.4-7.2) μm; SI 1.2; Stieda body absent. Oocysts of Isospora cottinghamae sp. n. are ellipsoidal, 19.8 × 15.5 (17.6-21.6 × 14.4-17.6) μm; SI 1.3; polar granules present. Sporocysts are ellipsoidal, 10.8 × 6.9 (9.6-12.8 × 6.4-8.0) μm; SI 1.6; Stieda body present. Oocysts of Isospora pearlae sp. n. are ellipsoidal, 16.0 × 11.5 (15.2-17.6 × 9.6-12.8) μm; SI 1.4; polar granule present. Sporocysts are ellipsoidal, 8.8 × 5.4 (8.0-9.6 × 4.8-6.4) μm; SI 1.6; Stieda and substieda bodies present. One new Eimeria species is described from the blue-tailed day gecko, Phelsuma cepediana Merrem. Oocysts of Eimeria hartleyi sp. n. are sub-spheroidal to ellipsoidal, 18.2 × 14.5 (16.0-20.8 × 13.6-16.0) μm; SI 1.26; polar granules present. Sporocysts are ellipsoidal to cylindroidal, 7.5 × 5.3 (6.4-8.0 × 4.8-6.4) μm; SI 1.4; Stieda body present. We report the presence of tetrazoic spheroidal to sub-spheroidal oocysts or sporocysts 10.2 × 8.5 (9.9-10.4 × 8.3-8.8) μm; SI 1.2 from an individual of P. cepediana. These oocysts or sporocysts are significantly larger than the Cryptosporidium species so far described from reptiles, and likely represent excretion of spuriously ingested sporocysts of a Sarcocystis or Adelina coccidian.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9056. Sixty years of Cybernetics: a comparison of approaches to solving the H2 control problem
- Creator:
- Kučera, Vladimír
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- linear systems, feedback control, stability, and norm minimization
- Language:
- English
- Description:
- The control problem consists of stabilizing a control system while minimizing the norm of its transfer function. Several solutions to this problem are available. For systems in form, an optimal regulator can be obtained by solving two algebraic Riccati equations. For systems described by , either Wiener-Hopf optimization or projection results can be applied. The optimal regulator is then obtained using operations with proper stable rational matrices: inner-outer factorizations and stable projections. The aim of this paper is to compare the two approaches. It is well understood that the inner-outer factorization is equivalent to solving an algebraic Riccati equation. However, why are the stable projections not needed in the state-space approach? The difference between the two approaches derives from a different construction of doubly coprime, proper stable matrix fractions used to represent the plant. The transfer-function approach takes any doubly coprime fractions, while the state-space approach parameterizes such representations and those selected then obviate the need for stable projections.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9057. Sixty years of Cybernetics: cybernetics still alive
- Creator:
- Havel, Ivan M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- cybernetics, general systems, transdisciplinarity, feedback, self-reference, collective phenomena, scales, hierarchies, emergence, downward causation, connectnism, chaos, autopoiesis, domains of discourse, causal domains, and metaphors
- Language:
- English
- Description:
- This informal essay, written on the occasion of 60th anniversary of Wienerian cybernetics, presents a series of themes and ideas that has emerged during last several decades and which have direct or indirect relationships to the principal concepts of cybernetics. Moreover, they share with original cybernetics the same transdisciplinary character.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9058. Sixty years of Cybernetics: From youthful to useful
- Creator:
- Klir, George J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- cybernetics, information theory, and scientific research
- Language:
- English
- Description:
- This year coincides with the 60-year anniversary of the publication of Norbert Wiener's seminal book: , in which he introduced, under the name "cybernetic", a host of radically new ideas and views regarding science, engineering, and other areas of human affairs that emerged shortly after World War II. It is thus appropriate for a journal whose title is , the Czech name for cybernetics, to use this anniversary for reflecting on the evolution of cybernetics during the last 60 years. In this essay, which I was invited to write for on this occasion, I intend to express my personal opinion about what I consider the most important ideas of cybernetics from among those suggested and discussed by Wiener in his book. In addition, I intend to trace the evolution of these principal ideas, especially in the United States, since the publication of Wiener's book.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9059. Sixty years of Cybernetics: the philosophical foundations of cybernetics
- Creator:
- Tondl, Ladislav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- cybernetics, philosophy, and interdisciplinary methods
- Language:
- English
- Description:
- The interdisciplinary workshops, focused on methodological and philosophical aspects, have helped - and still undoubtedly are helping - in forging links among different members of the academic community or research teams, which are today described as "intellectual networks" or "invisible colleges". Their focus of interest is known to transcend the boundaries of the traditionally divided scientific disciplines or research areas. That is also why the network that was instrumental in shaping the genesis of cybernetics includes, to this day, the names of C.Shannon, the pioneer of the mathematical theory of information, J.von Neumann, the founder of the theory of games and decision-making, linguist R.Jakobson, the above-mentioned specialists in the medicine- and biology-oriented branches, and many other scholars. Similar conceptions and aspirations connected therewith also proved to be conducive to the emergence and expansion of the works and studies devoted to the role of the sign, its creation, significance and function in communication, i.e. semantics and semiotics. Efforts were made to uncover more profound links and subsequently to outline paths leading to a unification of different scientific domains, particularly by integrating the language of science. There was a mounting interest in methodological and epistemological problems and - generally speaking - in finding ways and means of attaining more profound and thorough learning. All these and similar tendencies had and still have one common trait: they kept enhancing respect, weight and significance attached to mathematics, to mathematical methods of expressing and depicting problems, and to mathematical thinking in general.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9060. Sixty years of Ivan Netuka
- Creator:
- Král, Josef and Veselý, Jiří
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public