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474572. The local interstellar medium
- Creator:
- Blitz, Leo
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- space research, mollecular clouds, and interstellar medium
- Language:
- Czech
- Description:
- The structure of the local interstellar medium is reviewed with emphasis on the new observations of the cold neutral component. The properties of the high latitude molecular clouds are discussed as well as their relationship to the “infrared cirrus” and atomic gas. The molecular clouds are shown to the preferentially along the loops and filaments of local HI gas, but a detailed examination shows the CO and HI peaks are offset from one another. An expansion velocity of 7 km is derived for one of the shells suggesting an expansion energy of - 8 X 10^47 ergs. which is somewhat smaller than that expected for a supernova explosion. If the pressure in the clumps of the high latitude clouds is in equilibrium with the surrounding gas, the pressure in the shells is 10^4-10^5 cm^-3 K, an order of magnitude higher than what is generally argued to exist in the interstellar medium.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474573. The local kinematics of young objects
- Creator:
- Palouš, Jan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- statistics, kinematics, and general velocity
- Language:
- Czech
- Description:
- The radial velocities of star forming regions and young open star clusters from our galaxy are investigated statistically. We use the cubic, plane approximation of a general veloclty fleld and conclude that with all objects from our sample, which reside withln 10 kpc from the Sun, the veloclty field is close to clrcular. However, the young objects from the local spiral arm deviate. This deviatlon is dlfferent from that caused by the llnear denslty wave or by the collislonless expansion from a small region. We propose that the velocities of young local objects may be Interpreted as a consequence of a large scale multl-supernova remnant.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474574. The local metric dimension of a graph
- Creator:
- Okamoto, Futaba, Phinezy, Bryan, and Zhang, Ping
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- distance, local metric set, and local metric dimension
- Language:
- English
- Description:
- For an ordered set W = {w1, w2, . . . , wk} of k distinct vertices in a nontrivial connected graph G, the metric code of a vertex v of G with respect to W is the k-vector code(v) = (d(v, w1), d(v, w2), . . . , d(v, wk)) where d(v, wi) is the distance between v and wi for 1 6 i 6 k. The set W is a local metric set of G if code(u) 6= code(v) for every pair u, v of adjacent vertices of G. The minimum positive integer k for which G has a local metric k-set is the local metric dimension lmd(G) of G. A local metric set of G of cardinality lmd(G) is a local metric basis of G. We characterize all nontrivial connected graphs of order n having local metric dimension 1, n − 2, or n − 1 and establish sharp bounds for the local metric dimension of a graph in terms of well-known graphical parameters. Several realization results are presented along with other results on the number of local metric bases of a connected graph.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474575. The location of the central hall in the Ptolemaic temples
- Creator:
- Gaber, Amr
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Ptolemaic period and Central Hall
- Language:
- English
- Description:
- The present article tackles the subject of the location of the Central Hall in the Egyptian temples of the Ptolemaic period. According to the texts of the temples, the hall in question was situated between the Sanctuary and the Hall of Offerings. A hall with such a strategic position should have been used by the ancient Egyptians to take advantage of its features. Hence, four temples have been investigated: Edfu, Dendera, Philae and Kom Ombo. However, there were earlier theories concerning the location of the Central Hall and these have to be reconsidered. Recently, with the work conducted by Prof. J. F. Quack on the papyri of the Book of the Temple, there has been an enormous amount of information about the description of the ideal temple and its lay out and, in particular, the location of the Central Hall. Since it is a guidebook for the ideal temple, the information implies that it might have been followed or at least taken into consideration during the planning of the temples.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474576. The lock-and-key mechanisms of the internal genitalia of the Noctuidae (Lepidoptera): How are they selected for?
- Creator:
- Mikkola, Kauri
- Type:
- article, model:article, and TEXT
- Subject:
- Apamea, functional anatomy, species-specific, male vesica, female bursa, monandry, polyandry, evolution, genetic drift, sexual selection, zoogeography, and Holarctic sister species
- Language:
- English
- Description:
- In the Noctuidae, the owlet moths, the internal genitalia, i.e. the aedeagus and vesica (penis) in the males, and the bursa copulatrix in the females, together form a lock-and-key mechanism (LKM). The species-specific structures have their counterparts in the opposite sex. The internal LKM constitutes a specific reproductive isolation mechanism (lock-and-key hypothesis), which seem to be the rule in the ditrysian Lepidoptera, and also occurs in the Carabidae (Coleoptera) and some other insects. In contrast, the external genitalia rarely have species-specific counterparts in the sexes. Several results indicate the presence of LKMs: In the Noctuidae, (1) heterospecific differences in the male vesica may prevent sperm transfer or lead to mechanical failure during copulation, (2) the more complicated the specific genitalia structures, the more aberrations may occur even in conspecific copulations, and (3) in many species pairs and groups, and in one large genus, Apamea, the structures in the opposite sexes show a strictly specific correspondence, but, (4) when there is precopulatory isolation due to differences in pheromone production or perception, the internal genitalia may be identical. Conversely, in the Colias butterflies (Pieridae), (5) frequent heterospecific hybridization is associated with the similarity of the internal genitalia. The LKMs seem to protect genomes against alien genes, supposedly selected for because of the lower fitness of specimens with an imprecise LKM and/or inferiority of hybrids. In the literature, the diversity of the noctuid genitalia has been ascribed to sexual selection, because the females were classified as polyandrous. Most species produce the main part of their eggs monandrously, and remate, if at all, in their old age, and are thus successively monandrous and polyandrous. The allopatric divergence in the structure of the internal genitalia of 39 Holarctic pairs of sister species of Noctuidae is suggested to be due to genetic drift. The insecure function of the female pheromones and external genitalia of males are illustrated with the aid of original photographs.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474577. The logical and metaphysical structure of a common nature: a hidden aspect of Aquinas’mereology
- Creator:
- Svoboda, David
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Aquinas, mereology, and metaphysical whole/part
- Language:
- Slovak
- Description:
- The paper deals with a type of whole and part that can be found in Aquinas’ work and to which no attention has been paid so far. This type of whole and part can be called metaphysical whole and metaphysical part, respectively. In the paper, metaphysical whole and part are put forth on the problem of the logical and metaphysical structure of a common nature., Příspěvek pojednává o typu celku a jeho části, které lze nalézt v díle Akvinského a na které dosud nebyla věnována pozornost. Tento typ celku a části lze nazvat metafyzickou celou a metafyzickou částí. V příspěvku jsou metafyzický celek a jeho část uvedeny na téma logické a metafyzické struktury běžné povahy., and David Svoboda
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474578. The long-awaited first instar larva of Paussus favieri (Coleoptera: Carabidae: Paussini)
- Creator:
- Di Giulio, Andrea, Maurizi, Emanuela, Hlaváč, Peter, and Moore, Wendy
- Type:
- article, model:article, and TEXT
- Subject:
- Carabidae, Paussini, flanged bombardier beetles, Paussus favieri, first instar larva, taxonomy, functional morphology, myrmecophily, Formicidae, and Pheidole pallidula
- Language:
- English
- Description:
- Paussus favieri Fairmaire is one of only two species of the myrmecophilous carabid tribe Paussini known from Europe. Larvae are known from only 10 of the 580 paussine species. As in many beetles with considerably modified later instar larvae, the first instars represent a valuable source of informative characters for taxonomy and phylogenetic analyses (primary chaetotaxy, eggbursters, etc.). Therefore, the discovery of the first instar larva of P. favieri is particularly important, as it represents only the second species for which this larval stage is known. In this paper we describe the behavior and morphology of the larval first instar of P. favieri (subtribe Paussina of Paussini) and compare it with that of Arthropterus sp. (subtribe Cerapterina), which is the only other 1st instar described in the Paussini. Most surprisingly, we found that the 1st instar of P. favieri lacks a prostheca, which was previously thought to be a synapomorphy of Paussina + Platyrhopalina. Rather, P. favieri has a unique mandibular structure that seems to be functionally analogous to the protheca. It is a long, broadly lanceolate, distinctly flattened structure apparently homologous to the medial mandibular seta (MN2*), which arises from an area behind the cutting edge of mandible. We predict that the function of the protheca and this similar structure in P. favieri are involved in a specialized feeding strategy that may include soliciting trophallaxis from their host ants. We also report some observations of the first instar hatching from the egg, feeding on liquid and a behaviour we interpret as a “calling behavior,” all of which were videotaped and posted on the Tree of Life Web Project.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474579. The long-range variability of annual precipitation in Prague - Klementinum in the period 1805-1951 and in relation to the solar activity
- Creator:
- Křivský, Ladislav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- astrophysics and solar activity
- Language:
- Czech
- Description:
- The condition of measurement of precipitation from the year 1805 up-to the present time are defined. On the vasis of an analysis of the conditions and by comparison with the neighbouring stations a whole series of annual percipitation is homogenized. The original values in the period 1805-1830 are reduced for 8.7 %, the period 1840-1905 zemains unchanged, the period 1906-1951 is reduced partly for 10 % (Hlaváč), partly for 15 %. For the statement of long-range variability of the annual precipitation the method of double-time integral of precipitation deviations was used. The curves thus gained show a long-range variation having a contraty course regarding the secular curve of solat activity (90-year-rhythm). The long-range relation of the variability of annual precipitation to the secular solar activity is expounded by the change of circulation (showing the width of the frontal zone). Further a close connection between the course of yearly precipitaton nd Ejgenson´s Index of Recurrency of Sunspots was found, which is evidently applicable for Central-Europe. Immediately after the maximum of Recurrency Index there is a characteristic decrease of precititation, closely following the minimum of Recurrency Index there is remarkable rise. On the ground of extrapolation of the acquired secular curves of precipitation and on the ground of physically justified correlation with long-range solar activity, a prognosis of the course of the annual precipitation up to the year 2000 is defined. At present the long-range course of precipitaton shows the minimum, in the years 1970-1990 the precipitation should reach the secular maximum.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474580. The Long-term Development of Socio-spatial Differentiation in Socialist and Post-socialist Prague
- Creator:
- Špačková, Petra, Pospíšilová, Lucie, and Ouředníček, Martin
- Type:
- article, model:article, and TEXT
- Subject:
- socio-spatial differentiation, socialist and post-socialist city, population census, spatial variability, and Prague
- Language:
- Czech
- Description:
- The article examines how different social and urban processes were reflected in the spatial patterns of three dimensions of population structure (demographic, socio-economic, and ethnic statuses) in Prague during the socialist and post-socialist periods. The article has three main objectives. First, it analyses inertia and change in socio-spatial patterns and evaluates the processes that have influenced them. Second, it investigates how the importance of all three statuses in the spatial differentiation of urban space has evolved. Third, the article focuses on the level of geographical variability as recorded within different spatial scales, and the development of this variability. It examines selected indicators of socio-economic, demographic, and ethnic statuses by employing detailed statistical data on the level of basic settlement units from the Population Censuses held in 1970, 1991, and 2011. The results confirm that the most significant changes in socio-spatial patterns between socialism and post-socialism can be observed for ethnic spatial differentiation. In addition, the city witnessed considerable changes in demographic spatial patterns in both periods, while socio-economic spatial patterns have remained relatively stable. New socio-spatial processes driven predominantly by movements of young and better-off populations have taken place in previously less attractive neighbourhoods. As a result, very different populations often live side-by-side in contemporary Prague.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public