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33132. Rock anisotropy and brittleness from laboratory ultrasonic measurements in the service of hydraulic fracturing

Creator:
Moska, Rafal, Kasza, Piotr, and Maslowski, Mateusz
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
geodynamika, geomechanika, geofyzika, geologie, ultrasonografie, měření, geodynamics, geomechanics, geophysics, geology, index lámavosti, ultrasonic laboratory measurements, elastic anisotropy, brittleness index, 7, and 551
Language:
English
Description:
Ultrasonic velocity anisotropy in the rock provides information of variability of the dynamic elastic moduli. Young’s modulus and Poisson’s ratio calculated from waves velocities can be used to determine brittleness index, which is usually used to predict rock susceptibility for hydraulic fracturing. This paper describes laboratory ultrasonic measurements carried out in order to improve hydraulic fracturing designing. The research was conducted over two types of rock: shale and limestone. The samples were cut out perpendicularly and parallel to the bedding planes. Next they were tested for effective porosity and mineral composition using XRD method. Directionally depended seismic velocities revealed noticeable anisotropy of laminated shale, caused by orientation of the bedding planes and weak anisotropy of limestone. Based on the velocities, dynamic elastic moduli and its anisotropy coefficients were determined. Calculations of brittleness index based on Young’s modulus to Poisson’s ratio relation and three types of mineral composition brittleness indexes, revealed strong variability in brittleness for both kind of tested formations. These results show, that different types of brittleness indexes should be used complementary, to better describe fracability of the rock. and Moska Rafal, Kasza Piotr, Maslowski Mateusz.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

33133. Rock landforms that reflect differential relief development in the north-eastern sector of the Rychlebské hory and the adjacent area of Žulovská pahorkatina (SE Sudeten Mts, Czech Republic)

Creator:
Štěpančíková, Petra and Rowberry, Matt
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, geodynamika, geodynamics, Česká vysočina (pohoří), Krkonošsko-jesenická soustava (pohoří), Bohemian massif, Sudety mountains, rock landforms, pre-glacial, frost-riven cliffs, cryoplanation surfaces, blockfields, etch surfaces, residual hills, tors, 7, and 551
Language:
English
Description:
Rock landforms in the Sokolský hřbet (ridge) and the adjacent Žulovská pahorkatina (hilly land) have been analysed through detailed field mapping at a scale of 1:10,000; subsequently the spatial distribution of these features was analysed using a DEM within a GIS framework. Particular attention was focused upon the shape of the rock landforms, their arrangement, the aspect of their walls, and their topographic position within the two adjacent geomorphological units. Rock landforms in the Sokolský hřbet include frost-riven cliffs, isolated residual rockforms, and blockfields in metamorphic rocks. In contrast, rock landforms in the Žulovská pahorkatina include rock steps and numerous tors exposed from the basal weathering surface. The Sokolský hřbet has been interpreted as a neotectonically uplifted mountainous region; the rock landforms described here are thought to have formed under periglacial conditions during cold periods in the Pleistocene, whilst the extensive granitoid block accumulations developed on marginal fault scarps are thought to result from the exposure of intensively disintegrated rocks due to uplift. Žulovská pahorkatina has been interpreted as a remodelled stripped etch surface, which has been twice glaciated during the Middle Pleistocene. The rock landforms in both units appear to be structurally and lithologically controlled; moreover, various shapes of granite rock landforms are controlled by various types of jointing and parting. The clear differences recognised in both the rock landforms and overall morphology reflects the considerable disparity associated with relief development between two adjacent morphostructural units; such variability provides evidence for a long polygenetic history within the entire study area., Petra Štěpančíková and Matt Rowberry., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

33134. ROCK1 translocates from non-caveolar to caveolar regions upon KCl stimulation in airway smooth muscle

Creator:
Sommer, B., Montaño, L. M., Chávez, J., Carbajal, V., García-Hernandez, L. M., Irles, C., Jiménez-Garduño, A. M., and Ortega, A.
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, dýchací cesty, airways (medicine), bovine airway smooth muscle, rho-kinase1, caveolae, L-type Ca2+ channels, 14, and 612
Language:
English
Description:
Airway smooth muscle (ASM) me mbrane depolarization through KCl opens L-type voltage dependent Ca 2+ channels (Ca v 1.2); its opening was considered the caus e of KCl contraction. This substance is used to bypass intracellular second messenger pathways. It is now clear that KCl also activates RhoA/Rho kinase (ROCK) pathway. ROCK isoforms are characterized as ROCK1 and ROCK2. Because ROCK1 seems the most abundant isotype in lung, we studied its participation in KCl stimulated bovine ASM. With methyl- β -cyclodextrin (M β CD) we disrupted caveolae, a membrane compartment considered as the RhoA/ROCK assembly site, and found that KCl contraction was reduced to the same extent (~26 %) as Y-27632 (ROCK inhibitor) treated tissues. We confirmed that KCl induces ROCK activation and this effect was annulled by Y-27632 or M β CD. In isolated plasmalemma, ROCK1 was localized in non-caveolar membrane fractions in Western blots from control tissues, but it transferred to caveolae in samples from tissues stimulated with KCl. Ca v 1.2 was found at the non-caveolar membrane fractions in control and M β CD treated tissues. In M β CD treated tissues stimulated with KCl, contraction was abolished by nifedipine; only the response to Ca v 1.2 opening remained as the ROCK component disappeared. Our result s show that, in ASM, the KCl contraction involves the translocation of ROCK1 from non- caveolar to caveolar regions an d that the proper physiological response depends on this translocation., B. Sommer ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

33135. Rod v jazyce a komunikaci: specifika češtiny

Creator:
Čmejrková, Světla
Format:
print
Type:
model:internalpart and TEXT
Language:
Czech and English
Description:
The category of linguistic representation of men and women is one of the universal issues of language structure and use. Languages differ not only in that what they can express but also in what they must express. In this respect. Czech deserves a systematic study: Czech must reflect not only the gender of a referent - and does so more systematically than other languages - but regularly also the gender of a speaker and an addressee. The gender analysis of Czech must be related to genre analysis. This article focuses on symmetries and asymmetries in how men and women are named, addressed and referred to. Czech manifests a strong tendency toward separate symmetrical terms for both males and females. Though the processes of derivation of feminine counterparts from originally masculine forms are almost unlimited in Czech, the frequency of derived feminines in texts is much lower. This is due to the fact that masculine forms are used as a norm in gender-neutral and gender-indefinite contexts. The linguistic interpretation of the opposite gender pairs has been formed by the general background of structuralist treatment of linguistic meanings and functions. The concept of markedness and unmarkedness has been acknowledged in Czech linguistics also with regard to the interpretation of masculine terms in their unmarked. generic function (this interpretation is, of course, more legitimate in some of the discourse genres and less in others). The article addresses the issue of the linguistic awareness of Czech speakers and its potential change. New discourse practice might have shifted such masculines from gender-indefinite to gender-definite sphere of interpretation: in some contexts, masculine terms seem to be interpreted in a more gender-specific meaning than their unmarked, „inclusive“ meaning would suggest. The article gives a tentative outline of the scope of sensitive contexts (referential vs predicative positions, contrasting male vs female reference etc.).
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

33136. Rodent species composition, relative abundance, and habitat association in the Mabira Central Forest Reserve, Uganda

Creator:
Ssuuna, James, Makundi, Rhodes H., Isabirye, Moses, Sabuni, Christopher A., Babyesiza, Waswa S., and Mulungu, Loth S.
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
African ecology, small mammal community, lowland tropical forest, and Rodentia
Language:
English
Description:
A study was conducted in Mabira Central Forest Reserve in Uganda to determine rodent species composition, relative abundance, and habitat association. A total of 1,030 rodents belonging to 14 species were captured on 10,584 trap nights. Rodent species recorded include: Lophuromys stanleyi, Hylomyscus stella, Praomys jacksoni, Mastomys natalensis, Lophuromys ansorgei, Lemniscomys striatus, Aethomys hindei, Mus triton, Mus minutoides, Deomys ferrugineus, Gerbilliscus kempi, Rattus rattus, Grammomys kuru, and Hybomys univittatus. Overall, L. stanleyi (23.7%) was the most dominant species followed by H. stella, P. jacksoni, and M. natalensis. Species richness and evenness was highest in the regenerating forest habitat and least in the intact forest habitat. Rodent abundance was significantly affected by habitat type. The regenerating forest habitat had the highest number of animals, while the lowest numbers were observed in the depleted forest habitat. Species diversity was higher in regenerating forest habitat and lowest in the intact forest. The three habitats appeared distinct in terms of rodent species composition and there was a strong association between the two trapping grids in the same habitat type. All ordination plots showed that different rodent species consistently associated with distinct habitats. Habitat type and seasonal changes influenced rodent composition, relative abundance and habitat association. Composition of rodent community reflected the level of habitat degradation and can be used as a proxy for evaluating the biodiversity of lowland tropical forests.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

33137. Rodents as intermediate hosts of Hepatozoon ayorgbor (Apicomplexa: Adeleina: Hepatozoidae) from the African ball python, Python regius?

Creator:
Sloboda, Michal, Kamler, Martin, Bulantová, Jana, Votýpka, Jan, and Modrý, David
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
haemogregarines, Adeleina, Hepatozoon, transmission, ICR mice, and life cycle
Language:
English
Description:
Two experimental trials were performed to elucidate the role of rodents in the life cycle of Hepatozoon species using snakes as intermediate hosts. In one trial, two ball pythons, Python regius Shaw, 1802 were force fed livers of laboratory mice previously inoculated with sporocysts of Hepatozoon ayorgbor Sloboda, Kamler, Bulantová, Votýpka et Modrý, 2007. Transmission was successful in these experimentally infected snakes as evidenced by the appearance of intraerythrocytic gamonts, which persisted until the end of trial, 12 months after inoculation. Developmental stages of haemogregarines were not observed in histological sections from mice. In another experimental trial, a presence of haemogregarine DNA in mice inoculated with H. ayorgbor was demonstrated by PCR in the liver, lungs and spleen.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

33138. Rodents of Choke Mountain and surrounding areas (Ethiopia): the Blue Nile gorge as a strong biogeographic barrier

Creator:
Kostin, Danila S. , Martynov, Aleksey A. , Komarova, Valeria A. , Alexandrov, Dmitriy Yu. , Yihune, Mesele , Kasso, Mohammed , Bryja, Josef , and Lavrenchenko, Leonid A.
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
biogeography, Ethiopian highlands, Lophuromys, Stenocephalemys, and small mammals
Language:
English
Description:
Faunal studies of rodent assemblages from the areas on and around Choke Mountain (north-western Ethiopia) were conducted during two field seasons in 2012 and 2018. Here we present results of a genetic study of nine rodent species, and evaluate their genetic diversity and evolutionary relationships between conspecific populations from neighbouring montane massifs. Results of comparative analysis of phylogeographic patterns in Lophuromys, Desmomys, Stenocephalemys and Tachyoryctes have emphasized the role of the Blue Nile gorge as a strong biogeographic barrier, separating “northern” and “southern” independently evolved populations. Results of genetic analysis also revealed the presence of a new taxon of Dendromus, presumably belonging to a new species. Our study allows re-evaluation this area as an important “hotspot” of Ethiopian small mammal biodiversity.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

33140. Rodinná psychosomatika

Creator:
Balcar, Karel
Format:
electronic, electronic resource, and remote
Type:
model:article, article, Text, and TEXT
Subject:
lidé, psychosomatické poruchy--etiologie--psychologie, vztahy mezi rodiči a dětmi, zdraví rodiny, rodina--psychologie, psychologická teorie, modely psychologické, and psychosomatická rodina
Language:
Czech and English
Description:
Příspěvek nabízí pohled na tradiční pojem „psychosomatických rodin“ z hlediska jeho současné platnosti a užitečnosti. Poukazuje na výzkumné a klinické zkušenosti s častějším výskytem psychosomatických onemocnění u rodin s určitými poruchovými vlastnostmi struktury a interakce, v nichž tělesný projev nemoci plní účelnou, krátkodobě takovou rodinu ochraňující, dlouhodobě ji v její porušenosti ustalující a vývojově ji poškozující úlohu. Výsledkem má být připomenutí si vlastností takto rizikovějších rodin s výhledem na diagnostické rozpoznávání a porozumění funkci takového psychosomatického dění a zacílení terapeutické pomoci ke zdravějším způsobům zvládání rodinného stresu, než poskytuje takto probíhající patogenní „vyrovnávání účtů“ vzájemných potřeb v rodinném soužití., The paper presents a review of the traditional concept of „psychosomatic families“ from the viewpoint of its present validity and usefulness. It refers to research and clinical pieces of experience with more frequent occurrence of psychosomatic diseases in families that exhibit certain dysfunctional traits of structure and interaction, in which the somatic symptom fulfils an effective function in momentarily protecting the family from breakdown, however, in the long run, solidifying its ongoing malfunction and developmental impairment. The aim of the study is to remind of the typical characteristics of the families with such risks, with a view to diagnostic identification as well as understanding the function of such psychosomatic development, and leveling the therapeutic help to establishing more healthy ways of coping with family stress, than the ongoing pathogenic “squaring up“ of mutual needs in family cohabitation makes possible., Balcar K., and Literatura
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

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