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10412. Wainhouse D., 2005: Ecological methods in forest pest management
- Creator:
- Plhal, Radim
- Type:
- article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
10413. Wardium paucispinosum sp. n. (Eucestoda: Hymenolepididae), parasite of Larus maculipennis (Aves: Laridae) in Mar dcl Plata, Argentina; with comments on Wardium semiductilis (Szidat, 1964) comb. n.
- Creator:
- Labriola, Juliana Beatrix and Suriano, Delia Mabel
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Eucestoda, Argentina, Laridae, Wardium, and Hymenolepididae
- Language:
- English
- Description:
- A new species Wardium paucispinosum (Eucestoda: Hymenolepididae) parasite from the intestine of Larus maculipennis (Lichtenstein) from Mar del Plata, Argentina is described. The distinctive features of the new species are: strobilar length 52.8 mm; 10 aploparaksoid rostellar hooks, 14 (12-17) pm long; ratio between cirrus pouch length and mature proglottid width (CPL/MPW) 0.38 (0.27-0.50); regular cylindrical evaginated cirrus, 90 x 10 pm, with distal end without spines and proximal and medium thirds covered with spines 7 pm long; simple tubular membranous vagina, 110 x 10 pm, without sclcrotised portions and sphincters; eggs fusiform, 77 x 44 pm. Besides, llymenolepis semiductilis Szidat, 1964, from the intestine of Larus dominicanus and L. maculipennis from Santa Fé, Argentina is transferred to the genus Wardium Mayhew, 1925, based on the presence and shape of the rostellar hooks.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10414. Warp-speed adaptation to novel hosts after 300 generations of enforced dietary specialisation in the seed beetle Callosobruchus maculatus (Coleoptera: Chrysomelidae: Bruchinae)
- Creator:
- Price, Thomas N., Leonard, Aoife, and Lancaster, Lesley T.
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, mandelinkovití, beetles, Chrysomelidae, Coleoptera, Bruchinae, Callosobruchus maculatus, emerging crop pests, host shifts, genetic variation, adaptation trajectory, evolvability, experimental evolution, quasi-natural selection, heritability, 2, and 59
- Language:
- English
- Description:
- Herbivorous insects are often highly specialised, likely due to trade-offs in fitness on alternative host species. However, some pest insects are extremely adaptable and readily adopt novel hosts, sometimes causing rapid expansion of their host range as they spread from their original host and geographic origin. The genetic basis of this phenomenon is poorly understood, limiting our ability to predict or mitigate global insect pest outbreaks. We investigated the trajectory of early adaptation to novel hosts in a regionally-specialised global crop pest species (the cowpea seed beetle Callosobruchus maculatus). After experimentally-enforced dietary specialisation for nearly 300 generations, we measured changes in fitness over the first 5 generations of adaptation to 6 novel hosts. Of these, C. maculatus reproduced successfully on all but one, with reduced fitness observed on three hosts in the first generation. Loss of fitness was followed by very rapid, decelerating increases in fitness over the first 1-5 generations, resulting in comparable levels of population fitness to that observed on the original host after 5 generations. Heritability of fitness on novel hosts was high. Adaptation occurred primarily via changes in behavioural and phenological traits, and never via changes in offspring survival to adulthood, despite high heritability for this trait. These results suggest that C. maculatus possesses ample additive genetic variation for very rapid host shifts, despite a prolonged period of enforced specialization, and also suggest that some previously-inferred environmental maternal effects on host use may in part actually represent (rapidly) evolved changes. We highlight the need to examine in more detail the genetic architecture facilitating retention of high additive genetic variation for host shifts in extremely adaptable global crop pests., Thomas N. Price, Aoife Leonard, Lesley T. Lancaster., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10415. Water turbine power control - feasible conception
- Creator:
- Němec, Zdeněk and Němec, Vojtěch
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- water power plant, water turbine, power control, and water turbine control
- Language:
- English
- Description:
- This paper is concerned with Francis water turbine power control issue. There are introduced six conceptions of power controllers and corresponding control loop features are discussed. The control features are illustrated with step responses and the major attention is paid to the undesirable under-control effect. On an example of control system with an elementary description and with relatively short turbine pipeline feeder are the control features compared. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10416. Wavelet decomposition in the earth's gravity field investigation
- Creator:
- Bogusz, Janusz, Klos, Anna, and Kosek, Wieslaw
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, gravitace, zemětřesení, gravity, earthquake, GGP, wavelet decomposition, Earth’s gravity field changes, 7, and 551
- Language:
- English
- Description:
- This paper presents the results of the application of wavelet decomposition to processing data from the GGP sites (The Global Geodynamics Project). The GGP is an international project within which the Earth's gravity field changes are recorded with high accuracy at a number of stations worldwide using superconducting gravimeters. Data with a 5-second sampling interval from Wettzell and Bad Homburg were used for the research. The wavelet transform enables the investigation of the temporal changes of the oscillation amplitudes or the decomposition of the time series for the analysis of the required frequencies. The wavelet decomposition was performed using the regular orthogonal symmetric Meyer wavelet. The research concerned data from an earthquake period recorded at various locations and a quiet period when the gravimeters worked without any disturbances. The decomposition was followed by the Fast Fourier Transform for signal frequency components and then by correlation analyses of corresponding frequency components (for periods from 10 to 60 000 seconds) for all sensor combinations, for the quiet and the earthquake periods separately. Frequency components defining long term changes for all sensor combinations, as well as combinations between two sensors at the same site for the quiet days are characterised by high correlation coefficients. For the time of the earthquake, the Wettzell site data proved strong correlation for all frequency components, while the Bad Homburg site data showed an unexpected decrease of correlation for the majority of frequency components. The authors also showed that wavelet decomposition can be a good method of data interpolation, especially from the time of earthquakes. Moreover, it is a very useful tool for filtering the data and removing the noises., Janusz Bogusz, Anna Klos and Wieslaw Kosek., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10417. Weather conditions and breeding season length in blackbird (Turdus merula)
- Creator:
- Jankowiak, Łukasz, Pietruszewska, Hanna, and Wysocki, Dariusz
- Type:
- article, model:article, and TEXT
- Subject:
- climate change, temperature, phenology, phenotypic plasticity, and urban areas
- Language:
- English
- Description:
- The timing of egg laying by songbirds is known to be strongly affected by local climate, with temperature and precipitation being the most influential factors. However, most research to date relates only to the start of the breeding season: later records and the duration of the whole have not been taken into consideration. In the case of multibrooded species, productivity usually depends on the length of the breeding season. In this work we analysed climatic factors affecting breeding season length of an urban blackbird (Turdus merula) population. The study was conducted in two parks in the city of Szczecin, north-western Poland, spanning 14 breeding seasons since 1997. We found that over the study period, the breeding season became shorter as a result of colder springs and possibly because of warmer June-July temperatures. Our study revealed a positive relationship between breeding season length and the mean and mean minimum temperatures in April. Total precipitation in April-July also positively influenced breeding season length. The present survey confirms the influence of temperature and precipitation on the breeding season length of blackbird.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10418. Weibull fuzzy probability distribution for reliability of concrete structures
- Creator:
- Karpíšek, Zdeněk, Štěpánek, Petr, and Jurák, Petr
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- fuzzy probability distribution, fuzzy reliability, Weibull fuzzy distribution, and concrete structures
- Language:
- English
- Description:
- Based on the fuzzy probability distribution and its properties, the paper defines the fuzzy reliability and its characteristics for the double-stage probability model of object. Two fuzzy reliability models are described that are based on the Weibull fuzzy distribution. The results can be applied to determining the reliabililty of real objects in cases where pre-failure times are of a vague numerical type. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10419. Weighted empirical mode decomposition for processing GNSS position time series with the consideration of formal errors
- Creator:
- Qiu, Xiaomeng, Wang, Fengwei, Zhou, Yunqi, and Zhou, Shijian
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- satelitní navigační systémy, satellite navigation systems, weighted empirical mode decomposition, signal extraction, GNSS position time series, empirical mode decomposition, formal errors, 7, and 551
- Language:
- English
- Description:
- Empirical Mode Decomposition (EMD) is suitable to process the nonlinear and non-stationary time series for filtering noise out to extract the signals. The formal errors are provided along with Global Navigation Satellite System (GNSS) position time series, however, not being considered by the traditional EMD. In this contribution, we proposed a modified approach that called weighted Empirical Mode Decomposition (weighted EMD) to extract signals from GNSS position time series, by constructing the weight factors based on the formal errors. The position time series over the period from 2011 to 2018 of six permanent stations (SCBZ, SCJU, SCMN, HLFY, FJPT, SNXY) were analyzed by weighted EMD, as well as the traditional EMD. The results show that weighted EMD can extract more signals than traditional EMD from original GNSS position time series. Additionally, the fitting errors were reduced 14.52 %, 12.25 % and 8.06 % for North, East and Up components for weighted EMD relative to traditional EMD, respectively. Moreover, 100 simulations of four stations are further carried out to validate the performances of weighted EMD and traditional EMD. The mean Root Mean Squared Errors (RMSEs) are reduced from traditional EMD to weighted EMD with the reductions of 9.08 %, 9.63 % and 6.84 % for East, North and Up components, respectively, which highlights the necessity of considering the formal errors. Therefore, it reasonable to conclude that weighted EMD can extract the signals more than traditional EMD, which can be suggested to analyze GNSS position time series with formal errors., Xiaomeng Qiu, Fengwei Wang, Yunqi Zhou and Shijian Zhou., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10420. Weketrema gen. n., a new genus for Weketrema hawaiiense (Yamaguti, 1970) comb. n. (Digenea: Lecithasteridae) recently found in Australian marine fishes
- Creator:
- Bray, Rodney A. and Cribb, Thomas H.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Digenea, Lecithasteridae, Weketrema, Scolopsis, Plectorhinchus, Cheilodactylus, Latridopsis, Great Barrier Reef, and Tasmania
- Language:
- English
- Description:
- A new genus, Weketrema, is erected in the family Lecithasteridae for the species hitherto known as Lecithophyllum hawaiiense. Weketrema hawaiiense (Yamaguti, 1970) comb. n. is redescribed from Scolopsis bilineatus (Bloch) (Perciformes: Nemipteridae) from Lizard Island and Heron Island, Queensland, Plectorhinchus gibbosus (Lacepède) (Perciformes: Haemulidae) from Heron Island and Cheilodactylus nigripes Richardson (Perciformes: Cheilodactylidae) and Latridopsis forsteri (Castelnau) (Perciformes: Latridae) from Stanley, northern Tasmania. The new genus is distinguished from related members of the family Lecithasteridae by its complete lack of a sinus-sac. Although placed in the subfamily Lecithasterinae pro tem, its true subfamily position is not entirely clear. Comment is made on its unusual distribution, both in terms of zoogeography and hosts.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public