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
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
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
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.
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.
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
The aim of this contribution is to present a basic survey of publications dealing with the means of vibration suppression in several kinds of self-excitation. The attention is given to passive and active means using parametric excitation. A special attention is given to the latter and the necessary steps for answering important questions are formulated to initiate further investigation and especially application to real systems. and Obsahuje seznam literatury
Smoking is the most important cardiovascular (CV) risk factor. Stopping smoking halves the CV risk. Every clinician should provide a brief intervention with smokers. Intensive treatment should be available to those who need it. There are 37 Centers for Tobacco Dependence in the Czech Republic, which offer treatment including a psychobehavioral intervention and pharmacotherapy (varenicline, nicotine, bupropion). Czech physicians, pharmacists and nurses are regularly educated about smoking cessation. We describe the results of intensive treatment offered by our centers. Treatment includes screening (1 h), an intervention (2 h), and follow-up visits during the next 12 months. Among 3532 patients, 34.3 % had CO-validated abstinence at 12-months (including 489 patients who attended the screening visit + only the 12-month follow up visit). Among patients who underwent the intervention, the abstinence rate was 38.2 %. The majority of patients who underwent the intervention (N=2470) used some form of pharmacotherapy. After one year, the abstinence rate was 43.4 %, compared to 15.9 % (N=573) without pharmacotherapy. Only 28 % of patients came on the recommendation of a physician. Despite the decrease in CV risk following smoking cessation and the effectiveness of treatment, centers are underutilized., E. Králíková, A. Kmeťová, L. Štěpánková, K. Zvolská, V. Felbrová, S. Kulovaná, Z. Bortlíček, M. Blaha, K. Fraser., and Obsahuje bibliografii
Fuzzy algebra is a special type of algebraic structure in which classical addition and multiplication are replaced by maximum and minimum (denoted ⊕ and ⊗ , respectively). The eigenproblem is the search for a vector x (an eigenvector) and a constant λ (an eigenvalue) such that A⊗x=λ⊗x , where A is a given matrix. This paper investigates a generalization of the eigenproblem in fuzzy algebra. We solve the equation A⊗x=λ⊗B⊗x with given matrices A,B and unknown constant λ and vector x . Generalized eigenvectors have interesting and useful properties in the various computational tasks with inexact (interval) matrix and vector inputs. This paper studies the properties of generalized interval eigenvectors of interval matrices. Three types of generalized interval eigenvectors: strongly tolerable generalized eigenvectors, tolerable generalized eigenvectors and weakly tolerable generalized eigenvectors are proposed and polynomial procedures for testing the obtained equivalent conditions are presented.
Clinical and experimental studies have repeatedly indicated that overloaded hearts have a higher vulnerability to ischemia/reperfusion injury. The aim of the present study was to answer the question whether the degree of tolerance to oxygen deprivation in hearts of spontaneously hypertensive rats (SHR) may be sex-dependent. For this purpose, adult SHR and their normotensive control Wistar Kyoto (WKY) rats were used. The isolated hearts were perfused according to Langendorff at constant pressure (proportionally adjusted to the blood pressure in vivo). Recovery of contractile parameters (left ventricular systolic, diastolic and developed pressure as well as the peak rate of developed pressure) was measured during reperfusion after 20 min of global no-flow ischemia in 5 min intervals. Mean arterial blood pressure was measured by direct puncture of carotid artery under light ether anesthesia in a separate group of animals. The degree of hypertension was comparable in both sexes of SHR. The recovery of contractile functions in SHR males and females was significantly lower than in WKY rats during the whole investigated period. There was no sex difference in the recovery of WKY animals; on the other hand, the recovery was significantly better in SHR females than in SHR males. It may be concluded that the hearts of female SHR are more resistant to ischemia/reperfusion injury as compared with male SHR. This fact could have important clinical implications for the treatment of cardiovascular disease in women., J. Bešík, O. Szárszoi, J. Kuneš, I. Netuka, J. Malý, F. Kolář, J. Pirk, B. Ošťádal., and Obsahuje bibliografii a bibliografické odkazy