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33492. To crustal deformation modeling of the West Bohemia swarm area, Central Europe
- Creator:
- Vladimír Schenk and Zdeňka Schenková
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, družicová geodezie, satellite geodesy, Čechy západní (Česko), Bohemia, Western (Czechia), crustal deformation, seismic cycle, 7, and 551
- Language:
- English
- Description:
- In this article we solve the non-standard situation that arose after publishing our paper "Crustal deformations in the epicentral area of the West Bohemia 2008 earthquake swarm in central Europe" (Schenk et al., 2012). Horálek and Fischer wrote a statement regarding our publication, sent it to specialists interested in research in the West Bohemia swarm area, and questioned the reliability of the seismic data used in our work. Since the statement regarding the reliability of our work was not directly sent to us we are using this journal to return to professional discussion regarding our results. In this paper we review scientific arguments made in their statement and provide review of various studies on West Bohemia tectonics and related seismicity., Vladimír Schenk and Zdeňka Schenková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
33493. To dismantle injustice you should understand its roots: Alf Hornborg, Nature, society, and justice in the Anthropocene: Unraveling the money-energy-technology complex
- Creator:
- Černík, Mikuláš
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
33494. To fly or not to fly: Factors influencing the flight capacity of carabid beetles (Coleoptera: Carabidae)
- Creator:
- Venn, Stephen
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, biogeografie, kolonizace, biogeography, colonization, Coleoptera, Carabidae, aeroplankton, anemohydrochoric dispersal, autolysis, brachyptery, dispersal, disturbance, flight muscle, flight wing, histolysis, macroptery, migration, oogenesis flight syndrome, 2, and 59
- Language:
- English
- Description:
- This review considers factors affecting the flight capacity of carabid beetles and the implications of flight for carabids. Studies from the Dutch polders in particular show that young populations of carabids consist predominantly of macropterous species and macropterous individuals of wing-dimorphic species. Also populations of wing-dimorphic carabid species at the periphery of their geographical range contain high proportions of macropterous individuals. However, studies from Baltic archipelagos show that older populations of even highly isolated island habitats contain considerable proportions of brachypterous species and individuals. This suggests that macroptery is primarily an adaptation for dispersal and that there exists a mechanism for subsequently reducing the ratio of macropterous to brachypterous species under stable conditions, due to the competitive advantage of brachyptery. Populations in isolated habitats, such as islands and mountains, have high proportions of brachypterous species. Many macropterous species do not possess functional flight muscles. Species of unstable habitats, such as tree canopies and wet habitats, are mostly macropterous. Brachypterous species tend to disappear from disturbed habitats. There is uncertainty regarding the extent to which carabid dispersal is directed and how much passive. Both Den Boer and Lindroth recognized that mostly macropterous individuals of macropterous and wing-dimorphic species disperse and found new populations, after which brachyptery tends to rapidly appear and proliferate in the newly founded population. It is most likely that the allele for brachyptery would arrive via the dispersal of gravid females which had mated with brachypterous males prior to emigration. Whilst many studies consider wing morphology traits of carabid beetles to be species-specific and permanent, a number of studies have shown that the oogenesis flight syndrome, whereby females undertake migration and subsequently lose their flight muscles by histolysis before eventually regenerating them after reproducing, has been reported for a growing number of carabid species. Wing morphology of carabid beetles clearly offers strong potential for the study of population dynamics. This field of study flourished during the 1940's to the late 1980's. Whilst a considerable amount of valuable research has been performed and published, the topic clearly holds considerable potential for future study., Stephen Venn., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
33495. To joint effect of temperature and notch root radius on fracture toughness
- Creator:
- Elayachi, Ilyan, Pluvinage, Guy, Bensalah, Mohamed Omar, Lebienvenu, Michel, and Dlouhý, Ivo
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- notch fracture mechanics, fracture toughness, notch effects, stress triaxility, cast ferritic steel, and transition behaviour
- Language:
- English
- Description:
- For low-alloyed cast ferritic steel simultaneous effect of temperature and notch root radius on fracture toughness has been investigated. Due to fact that fracture tests were performed on notched specimens (cylindrical tensile specimens with circumferential notch having there notch root radii), the concept of Notch Fracture Mechanics was applied. Volumetric fracture criterion with two parameters, effective stress and effective distance, was developed. The goal of the work was to quantify the influence of notch radius on transition temperature and notch fracture toughness, and, in addition, to present jointly the role of both these parameters in fracture behaviour. In the case of the studied cast steel with a low yield stress (375 MPa), effective distance is 3 to 4 times longer than the Creager's effective distance (half of notch radius). The transition region and temperatures are shifted to higher values when notch radius decreases. At temperature higher than a temperature called plateau temperature Tp dactile filure appears. The Tp temperature is sensitive to nothe radius being affected by stress triaxiality. It is possible to define a notch sensitivity compensated temperature T* = √ρ/ρc. In the transition regime, critical notch stress intensity factor varies linearly with T*. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
33496. To mate or not to mate? Mate preference and fidelity in monogamous Ansell’s mole-rats, Fukomys anselli, Bathyergidae
- Creator:
- Bappert, Marie-Therese, Burda, Hynek, and Begall, Sabine
- Type:
- article, model:article, and TEXT
- Subject:
- monogamy, eusociality, extra-pair copulation, fidelity, mate choice, and African mole-rats
- Language:
- English
- Description:
- According to a hypothesis addressing the evolution of eusociality in mole-rats, the female (queen) is not able to raise her (first) offspring without a mate and thus to found a family. Therefore, we predict that the reproductive male (king) has to be socially faithful. In this study we tested this prediction and addressed the related question whether or not the presentation of a new female provokes enhanced sexual interest in male Ansell’s mole-rats (Fukomys anselli). We performed behavioral partner preference tests in Ansell’s mole-rats where two animals of choice were presented to a subject without allowing direct access. The kings spent significantly more time sniffing an unfamiliar queen or female than their own mate. If given the choice between an unfamiliar queen and her respective non-reproductive daughter, however, the tested kings significantly preferred the queen. In contrast, queens did not show a preference for either their own mate, an unrelated unfamiliar king, or a non-reproductive male. In a second experiment, we allowed the males to access the compartment of an unfamiliar female while their respective family stayed in an adjacent compartment. Only the non-reproductive adult males seized their chances to copulate with the unfamiliar female whereas the kings remained faithful. When reversing the test condition (i.e. females were given access to an unfamiliar male), aggressiveness of the males impeded sexual encounters in most cases. We recorded only three copulations, all of them between queens and non-reproductive males. We conclude that the reproductive status is crucial for reproductive decisions. Furthermore, the presence of family members influences the kings’ behavior. Since in Ansell’s mole-rats, repeated copulations over a longer period of cohabitation are necessary for ovulation and fertilization, the kings’ sexual fidelity could have been expected. We postulate that the maintenance of Ansell’s mole-rats’ families depends on the kings’ faithfulness.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
33497. To nejlepší nakonec
- Creator:
- Bahník, Štěpán
- Type:
- article, model:article, and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
33498. To není lišaj, ale kolibřík
- Creator:
- Krizek, George O.
- Type:
- article and TEXT
- Language:
- Czech
- Description:
- Zajímavosti ze života kolibříků a problematika jejich fotografování na příkladu severoamerického kolibříka šestibarvého (Selasphorus platycercus). and This article presents some remarkable features of hummingbird bionomics and the photographic issues involved. Special attention is paid to the North American Broad-tailed Hummingbird (Selasphorus platycercus).
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
33499. To the analysis of internal dynamics of special case in a class of non-linear parametric pseudoplanetary systems
- Creator:
- Hertel, Milan and Škuderová, Alena
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- non-linear dynamics, parametric systems, and planetary systems
- Language:
- English
- Description:
- Within the frame of the mass discretisation method has been designed the mathematical - physical model of the pseudoplanetary system of seven degrees of freedom for the analysis of the influence of the number of satellites and for free or elastic mounting of the sun wheel as a next phase of the solution of general differential system with branched - split power flow.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
33500. To the parametric anti-resonance application
- Creator:
- Tondl, Aleš and Půst, Ladislav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- parametric excitation, parametric resonance, parametric anti-resonance, and additional parmetric excitation
- Language:
- English
- Description:
- A new application of the parametric anti-resonance is discussed. This phenomenon can be used not only for suppressing self-excited vibration or to reduce the externally excited vibration but also to suppressing self-excited vibration or to reduce the externally excited vibration but also to suppress the parametric resonance when certain conditions are met. Another aim is to stimulate further investigations and the practical applications. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public