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1332. A sucker for the job: morphology and functioning of suckers of polystomatid monogeneans
- Creator:
- Heyns Du Preez, Louis and Theunissen, Maxine
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Polystomatidae, Monogenea, sclerite, morphology, haptoral sucker, type I, type II, type III, and type IV
- Language:
- English
- Description:
- Monogeneans rely on firm attachment to often flexible and uneven surfaces and are renowned for their effective posterior attachment structures in the form of adhesives, clamps, hamuli and suckers. Polystomatids do not secrete adhesives and do not have clamps. While only some have hamuli, all have suckers in the adult form. Three different types of haptoral suckers have been described based on basic morphology but have never been studied in depth. Using enzyme digestion and light (differential interference contrast), confocal and scanning electron microscopy, we examined representatives and propose four sucker types. Haptoral sucker Type I are symmetrical soft, flexible, cup- to disk-shaped suckers and are found in all polystomes infecting frogs and salamanders. Type II suckers are symmetrical soft, flexible, cup-shaped suckers with a hollow continuous skeletal ring and no other skeletal elements. They are found in species of Nanopolystoma Du Preez, Wilkinson et Huyse, 2008 infecting caecilians. Type III suckers are symmetrical firm, cup-shaped suckers with elaborate skeletal elements that contribute to a secure grip on the host tissue. This type of sucker is found in all polystomes infecting freshwater turtles and the common hippopotamus. Type IV suckers are asymmetrical with an elaborate series of long, thin sclerites with terminal spines or hooks. This type of sucker is only known from Concinnocotyla australensis (Reichenbach-Klinke, 1966) infecting the Australian lungfish. These different sucker types are crucial for the survival of polystomatid flatworms within their respective microhabitats.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1333. A survey of HIV and HCV among female prison inmates in Portugal
- Creator:
- Barros, Henrique
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1334. A Survey of Medieval Manuscripts Containing the Chronicle of Martin the Pole in Polish Collections /
- Creator:
- Soszyński, Jacek
- Type:
- text and studie
- Subject:
- Rukopisy, prvotisky, staré tisky. Vzácná a pozoruhodná díla, Martin z Opavy,, kroniky polské, Polsko, světové dějiny středověku (do r. 1492), and dějepisectví, historické vědy, historici
- Language:
- English
- Rights:
- unknown
1335. A swarm of the seven-spot ladybird Coccinella septempunctata (Coleoptera: Coccinellidae) carried on a cruise ship
- Creator:
- Minchin, Dan
- Type:
- article, model:article, and TEXT
- Subject:
- Swarm, ship transport, Coccinella septempunctata, and invasion
- Language:
- English
- Description:
- Several thousands of the seven-spot ladybird Coccinella septempunctata L., descended upon a cruise ship over several hours in daylight while in port in Morocco in April 2009. The ship had recently arrived from South America. Despite a treatment of fumigation beetles were found living after fourteen days following the inoculation event. This observation indicates an ocean transmission of large numbers of this species could take place and might have happened in the past.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1336. A swarm-based system for object recognition
- Creator:
- Mirzayans , Tanya, Parimi , Nitin, Pilarski , Patrick, Backhouse , Chris, Wyard-Scott, Loren, and Musilek, Petr
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Swarm intelligence, agent, computer vision, object recognition, and neural network
- Language:
- English
- Description:
- Swarm intelligence is an emerging field with wide-reaching application opportunities in problems of optimization, analysis and machine learning. While swarm systems have proved very effective when applied to a variety of problems, swarm-based methods for computer vision have received little attention. This paper proposes a swarm system capable of extracting and exploiting the geometric properties of objects in images for fast and accurate recognition. In this approach, computational agents move over an image and affix themselves to relevant features, such as edges and corners. The resulting feature profile is then processed by a classification subsystem to categorize the object. The system has been tested with images containing several simple geometric shapes at a variety of noise levels, and evaluated based upon the accuracy of the system's predictions. The swarm system is able to accurately classify shapes even with high image noise levels, proving this approach to object recognition to be robust and reliable.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1337. A swinging up controller for the Furuta pendulum based on the Total Energy Control System approach
- Creator:
- Rodríguez-Cortés, H.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- total energy control system, Furuta pendulum, swinging up control, and real-time experiments
- Language:
- English
- Description:
- This paper considers the problem of swinging up the Furuta pendulum and proposes a new smooth nonlinear swing up controller based on the concept of energy. This new controller results from the Total Energy Control System (TECS) approach in conjunction with a linearizing feedback controller. The new controller commands to the desired reference the total energy rate of the Furuta pendulum; thus, the Furuta pendulum oscillates and reaches a neighborhood of its unstable configuration while the rotation of its base remains bounded. Once the Furuta pendulum configuration is in the neighborhood of its unstable equilibrium point, a linear controller stabilizes the unstable configuration of the Furuta pendulum. Real-time experiments are included to support the theoretical developments.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1338. A synergy of differential evolution and bacterial foraging optimization for global optimization
- Creator:
- Biswas, Arijit, Dasgupta, Sambarta, Das, Swagatam, and Abraham, Ajith
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Bacterial foraging, hybrid optimization, differential evolution, genetic algorithm, and radar poly-phase code design
- Language:
- English
- Description:
- The social foraging behavior of Escherichia coli bacteria has recently been studied by several researchers to develop a new algorithm for distributed optimization control. The Bacterial Foraging Optimization Algorithm (BFOA), as it is called now, has many features analogous to classical Evolutionary Algorithms (EA). Passino [1] pointed out that the foraging algorithms can be integrated in the framework of evolutionary algorithms. In this way BFOA can be used to model some key survival activities of the population, which is evolving. This article proposes a hybridization of BFOA with another very popular optimization technique of current interest called Differential Evolution (DE). The computational chemotaxis of BFOA, which may also be viewed as a stochastic gradient search, has been coupled with DE type mutation and crossing over of the optimization agents. This leads to the new hybrid algorithm, which has been shown to overcome the problems of slow and premature convergence of both the classical DE and BFOA over several benchmark functions as well as real world optimization problems.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1339. A synopsis of records of myxozoan parasites (Cnidaria: Myxozoa) from shrews, with additional data on Soricimyxum fegati from common shrew Sorex araneus in Hungary and pygmy shrew Sorex minutus in Slovakia
- Creator:
- Szíkely, Csaba, Atkinson, Stephen D, Kálmán Molnár, Egyed, László, Gubány, Andrási, and Cech, Gábor
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- játra, liver, Evropa střední, Europe, Central, Eurasian shrew, Eurasian pygmy shrew, myxozoan infection, bile ducts, mammal hosts, 2, and 59
- Language:
- English
- Description:
- Myxozoans (Cnidaria: Myxozoa) are almost exclusively endoparasites of aquatic vertebrates and invertebrates, with the notable exception being two species of Soricimyxum Prunescu, Prunescu, Pucek et Lom, 2007 described from terrestrial shrews (Soricidae) in central Europe. Myxospores of the two parasites are morphologically indistinguishable, but have SSU rDNA sequences that differ by about 4%. Herein, we report additional molecular and histology data from Soricimyxum fegati Prunescu, Prunescu, Pucek et Lom, 2007 from common shrew (Sorex araneus Linnaeus) from Hungary, and add a new geographic record for S. fegati in pygmy shrew (Sorex minutus Linnaeus) from Slovakia. A limited survey of shrews from the northern United States, Blarina brevicauda Say and Sorex sp. from New York, and Sorex spp. from Oregon, did not discover any infections, which is in stark contrast to the relatively high infection rates (up to 66%) in European shrew populations. We also provide a summary and discussion of literature records of species of Soricimyxum and a host survey. Given the lack of distinguishing morphological or morphometric characters between Soricimyxum spp., and the overlap in vertebrate hosts and geographic ranges, unambiguous identification of these closely related shrew parasites can presently only be achieved through sequence comparison of one or more variable SSU rDNA regions., Csaba Székely, Stephen D. Atkinson, Kálmán Molnár, László Egyed, András Gubányi, Gábor Cech., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1340. A synoptic review of Caryophyllaeus Gmelin, 1790 (Cestoda: Caryophyllidea), parasites of cyprinid fishes
- Creator:
- Barčák, Daniel, Oros, Mikuláš, Vladimíra Hanzelová, and Tomáš Scholz
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- tasemnice, sladkovodní ryby, kaprovití, biologická systematika, tapeworms, freshwater fishes, Cyprinidae, biological systematics, identification key, phylogenetic relationships, Palaearctic Region, 2, and 59
- Language:
- English
- Description:
- Tapeworms of the genus Caryophyllaeus Gmelin, 1790 (Caryophyllidea: Caryophyllaeidae), common parasites of cyprinid fishes, are reviewed and taxonomic status of 42 nominal taxa that have been placed in the genus during its long history is clarified. The following seven species occurring in the Palaearctic Region are recognised as valid: C. laticeps (Pallas, 1781), C. auriculatus (Kulakovskaya, 1961), C. balticus (Szidat, 1941) comb. n. (syn. Khawia baltica Szidat, 1941), C. brachycollis Janiszewska, 1953, C. fimbriceps Annenkova-Chlopina, 1919, C. syrdarjensis Skrjabin, 1913, and newly described Caryophyllaeus chondrostomi sp. n. (= C. laticeps morphotype 4 of Bazsalovicsová et al., 2014) from common nase, Chondrostoma nasus (Linnaeus), found in Austria and Slovakia. The new species differs by the paramuscular or cortical position of preovarian vitelline follicles, a large, robust body (up to 64 mm long), conspicuously long vas deferens, flabellate scolex with small wrinkles on the anterior margin, and anteriormost testes located in a relatively short distance from the anterior extremity. Caryophyllaeus kashmirenses Mehra, 1930 and Caryophyllaeus prussicus (Szidat, 1937) comb. n. are considered to be species inquirendae, C. truncatus von Siebold in Baird, 1853 and C. tuba von Siebold in Baird, 1853 are nomina nuda. Data on the morphology, host spectra, distribution and known life-cycles of valid species are provided. Phylogenetic interrelations of four species of the genus including its type species and newly described C. chondrostomi were assessed based on an analysis of sequences of lsrDNA and cox1. A key to identification of all valid species of Caryophyllaeus is also provided., Daniel Barčák, Mikuláš Oros, Vladimíra Hanzelová, Tomáš Scholz., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public