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1652. A new live trap to catch blind mole rats (Spalax sp.)
- Creator:
- Arslan, Atilla
- Type:
- article, model:article, and TEXT
- Subject:
- live trapping and subterranean mammal
- Language:
- English
- Description:
- A design of a newly developed metal pipe-type trap for catching live mole rats is presented. In all field trials the trap was efficient and thus meaningful alternative to other types of live traps. This trap may prove to be useful also to catching the other subterranean mammal species.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1653. A new look at discontinuous respiration in pupae of Hyalophora cecropia (Lepidoptera: Saturniidae): Haemocoelic pressure, extracardiac pulsations and O2 consumption
- Creator:
- Sláma, Karel
- Type:
- article, model:article, and TEXT
- Subject:
- Saturniidae, Hyalophora cecropia, respiratory acidaemia, haemocoelic pulsations, respiratory movements, O2 consumption, spiracular pulsations, CO2 bursts, chemically produced CO2, and carbonic anhydrase
- Language:
- English
- Description:
- Discontinuous respiration in diapausing pupae of Cecropia silkworms was monitored by means of several electronic methods, including recording changes in haemocoelic pressure, monitoring respiratory movements by strain-gauge sensors and nanorespirographic recording of O2 consumption and CO2 output. It appears that, in contrast to previous concepts of stereotypic discontinuous respiration cycles (DGC) driven by accumulation of gaseous CO2 in the body, the new results indicate that CO2 remains dissolved in liquid carbonate buffers during interburst periods. In other words, there is no accumulation of gaseous CO2 within the air filled tracheal space between the bursts. The bursts of CO2 are caused by homeostatically regulated enzymatic hydration by carbonic anhydrase of metabolically produced carbonic acid. The chemically produced gaseous CO2 was exhaled mainly by a bulk outflow through selectively opened or pulsating spiracles. The output of CO2 was enhanced by actively regulated, unidirectional ventilation. The deep depressions in haemocoelic pressure, caused by permanent closure of all spiracular valves for long periods, appeared to be a specific feature of diapausing saturniid pupae. Physiologically, it has circulatory, not respiratory functions. The original definition of spiracular "fluttering" resulted from a misinterpretation of previously unknown extracardiac pulsations in haemocoelic pressure. The coordinated pulsation of the spiracular valves with extracardiac pulsations produce a very efficient, unidirectional ventilation of the whole tracheal system. According to the new results, the discontinuous respiration cycles of diapausing Cecropia pupae can be briefly described as follows: (1) Spiracular valves are kept permanently closed during the periods of deep depressions, they remain closed for some 99% of the time with occasional snap opening (passive inspirations) during prolonged interburst periods and more than 50% closed during the bursts; (2) During the long interburst periods, CO2 is retained in liquid carbonate buffers, while the relatively high (after the burst) or low (toward the next burst) rate of O2 consumption creates an internal vacuum, which is homeostatically compensated for by the snap-opening of one or just a few spiracular valves (passive suction inspirations); (3) The CO2 gas, produced enzymatically by carbonic anhydrase, enters the air filled tracheal system and leaves the body by diffusion, a bulk outflow, or actively regulated unidirectional ventilation ("fluttering" spiracles). The selective advantage of this actively regulated respiratory system for water retention in pupae is discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1654. A new look at the life-cycle of Hoferellus carassii in the goldfish (Carassius auratus auratus) and its relation to “kidney enlargement disease” (KED)
- Creator:
- Trouillier, Alexander, El-Matbouli, Mansour, and Hoffmann, Rudolf W.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Myxosporea, Hoferellus carassii, Actinosporea, Aurantiactinomyxon, and Nais sp.
- Language:
- English
- Description:
- The unknown oligochaete host in the life-cycle of Hoferellus carassii Achmerov, 1960 was identified as a member of the family Naididae, the genus Nais (most probably Nais elinguis). The aurantiactinomyxon spore found by El-Matbouli et al. ( 1992a) is demonstrated to be the actinosporean stage of Hoferellus carassii. The development of this spore within the naidid host is described by electron microscopy, and the results compared with those of Janiszewska (1955, 1957) and Marqués (1984. 1986) for Actinosporea originally described as a separate group of parasites. Additionally the plasmodial development of H. carassii within the urinary bladder of the goldfish (Carassius auratus auratus Linnaeus, 1758) is described.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1655. A new look at totally positive matrices
- Creator:
- Miroslav Fiedler
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- matematika, mathematics, totally positive matrix, Monge matrix, semigroup, Vandermonde-like matrix, 13, and 51
- Language:
- English
- Description:
- A close relationship between the class of totally positive matrices and anti-Monge matrices is used for suggesting a new direction for investigating totally positive matrices. Some questions are posed and a partial answer in the case of Vandermonde-like matrices is given., Miroslav Fiedler., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1656. A new look at transudation: the apocrine connection
- Creator:
- Farkaš, Robert , Beňo, Milan , Beňová-Liszeková, Denisa , Raška, Ivan , and Raška, Otakar
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- transcellular transport, vacuolation, endosome trafficking, vesicular cargo, exocytosis, apocrine secretion, transcytosis, and transudation
- Language:
- English
- Description:
- Transcellular trafficking in which various molecules are transported across the interior of a cell, is commonly classified as transcytosis. However, historically this term has been used synonymously with transudation. In both cases transcellular trafficking starts with the internalization of proteins or other compounds on the basal or basolateral side of a cell and continues by their transport across the interior to the apical pole (or vice versa) where they are subsequently released. This allows a cell to release products which are synthesized elsewhere. Here, we discuss the common features of both transcytosis and transudation, and that which differentiates them. It appears that transcytosis and transudation are identical in terms of vesicular import and endosomal sorting of cargo, but completely differ in the re-secretion process. Specialized epithelial cells re-release substantial quantities of the endocytosed material, and often also a great variety. Some recent studies indicate that this is achieved by non-canonical apocrine secretion rather than by the regular vesicular mechanism of exocytosis, and takes place only on the apical pole. This massive re-release of endocytosed proteins, and potentially other compounds via the apocrine mechanism should be considered as transudation, distinct from transcytosis.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1657. A new method based on indirect evidences to infer activity pattern in moles. A test on the blind mole in Central Apennines
- Creator:
- Di Febbraro, Mirko and Loy, Anna
- Type:
- article, model:article, and TEXT
- Subject:
- Talpa caeca and circadian rhythms
- Language:
- English
- Description:
- The study of activity patterns in subterranean mammals has been poorly explored in subterranean insectivores. This is especially true for the rare and elusive blind mole Talpa caeca. A field work devoted to collect data on life history traits of the blind mole was run in a montane pasture in Southern Italy (1549 m a.s.l.). Plastic barrel-like traps were placed in actively used mole tunnels and checked regularly at 6 h intervals for two sessions of nine consecutive days, for a total 1500 trap-nights. No moles were captured alive, but signs of mole activity at trap sites (traps filled with ground) were regularly recorded. A video recorded inside a trap confirmed that moles fill the traps with soil as part of trap avoidance behavior. Activity at trap sites was analyzed as a binomial variable, considering the rate of filled traps vs.the number of armed traps at each 6 h trap-checking intervals. Activity showed a polyphasic pattern typical of moles, but differently from other species, activity was more concentrated in the central part of the day (12.00-18.00). Results suggest a specific adaptation to local environmental conditions and body size.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1658. A new method for combinatorial optimization: genetic neighborhood search
- Creator:
- Domínguez, Juan José, Lozano, Sebastián, Calle, Marcos, and Smith, Kate
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- combinatorial optimization, genetic algorithm, neighborhood search, ejection chains, and traveling salesman problem
- Language:
- English
- Description:
- Combinatorial optimization is a discipline of decision making in the case of diserete alternatives. The Genetic Neighborhood Search (GNS) is a hybrid method for these combinatorial optimization problems. The main feature of the approach is iterative use of local search on extended neighborhoods, where the better solution will be the center of a new extended neighborhood. When the center of the neighborhood would be t.he better solution the algorithm will stop. We propose using a genetic algorithm to exi)lore the extended neighborhoods. This GA is characterized by the method of evaluating the fitness of individuals and useing two new operators. Computational experience with the Symmetric TSP shows that this approach is robust with respect to the starting point and that high quality solutions are obtained in a reasonable time.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1659. A new method for the release of Amblyseius andersoni (Acari: Phytoseiidae) in young apple orchards
- Creator:
- Szabó, Árpád and Pénzes, Béla
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Acari, Phytoseiidae, Amblyseius andersoni, mite release, apple, mite management, 2, and 59
- Language:
- English
- Description:
- The use of phytoseiid species in biological plant protection is widespread. However, the techniques used to release them differ. The possible release of Amblyseius andersoni (Chant, 1959) using a new method was tested. High numbers of this mite overwinter in the ground litter in Hungarian orchards. By transferring such ground litter to plots in young orchards, the population density was found to be significantly increased in the release compared to control plots; A. andersoni became the dominant phytoseiid species in the new orchard. Due to the rate at which it spreads, this species was also recorded in the control plots towards the end of the growing season (Aug., Sept.), at which time there was no significant difference in the numbers of this species in the treated and control plots. In the winter following release, A. andersoni was found in the ground litter of the orchard., Árpád Szabó, Béla Pénzes., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1660. A new method of assembling large magnetic blocks from permanent NdFeB magnets
- Creator:
- Žežulka, Václav and Pavel Straka
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, magnetické obvody, magnetic circuits, magnet assembly, magnetic separation, magnetic filtration, permanent magnets, NdFeB magnets, large magnetic blocks, 7, and 551
- Language:
- English
- Description:
- The presented technological procedure makes it possible to assemble large magnetic blocks from permanent magnets with a high value of maximum energy product in such a way that the individual magnets or magnetic plates are moved toward each other at a controlled speed in the direction perpendicular to the future common contact surface of these magnets, i.e. parallel to the induction lines crossing this contact surface. Unlike in the previously used way of assembling the blocks, it is thus possible to eliminate the influence of partial demagnetization as the blocks are being assembled and consequently to reach higher values of magnetic induction in the air gap of the magnetic circuit. When applying the new method of assembling the blocks for instance in circuits of magnetic filters for the purification of ceramic suspensions, a prerequisite for the further improvement of the technological parameters of filtration is thus created., Václav Žežulka and Pavel Straka., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public