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252. Ultrastructure and phylogeny of Glugea nagelia sp. n. (Microsporidia: Glugeidae), infecting the intestinal wall of the yellowfin hind, Cephalopholis hemistiktos (Actinopterygii: Serranidae), from the Red Sea
- Creator:
- Abdel-Baki, Abdel-Azeem S, Al-Quraishy, Saleh, Rocha, Sónia, Dkhil, Mohamed A, Casal, Graça, and Azevedo, Carlos
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitické organismy, parasitic organisms, fish parasite, microsporidian, fine structure, rRNA genes, 2, and 59
- Language:
- English
- Description:
- A new microsporidian species of the genus Glugea Thélohan, 1891 parasitising the marine teleost fish Cephalopholis hemistiktos Rüppell, collected from the Red Sea in Saudi Arabia, is described on the basis of microscopic and molecular procedures. Spherical and whitish xenoma were observed adhering to the intestinal wall. The numerous spores contained within these xenoma, were ovoid to pyriform and measured 4.3-6.0 µm (5.1 µm) in length and 1.8-2.9 µm (2.2 µm) in width. The spore's wall was composed of two thick layers, which were thinner in the area contacting the anchoring disk. The latter appeared at the spore's anterior pole, in an eccentric position to the longitudinal axis. A lamellar polaroplast surrounded the uncoiled portion of the polar filament projected to the basal region of the spore, giving rise to 26-29 turns with winding from the base to the anterior zone of the spore. The posterior vacuole, located at the spore's posterior pole, and surrounded by the polar filament coils, was irregular and composed of light material. Molecular analysis of the rRNA genes, including the ITS region, was performed using maximum parsimony, neighbour-joining and maximum likelihood methods. The ultrastructural features observed, combined with the phylogenetic data analysed, suggest this parasite to be a new species of the genus Glugea. This is the first species of this genus to be reported from Saudi Arabia and is herein named Glugea nagelia sp. n., Abdel-Azeem S. Abdel-Baki, Saleh Al-Quraishy, Sónia Rocha, Mohamed A. Dkhil, Graça Casal, Carlos Azevedo., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
253. Ultrastructure of the anterior organ and posterior funnel-shaped canal of Gyrocotyle urna Wagener, 1852 (Cestoda: Gyrocotylidea)
- Creator:
- Poddubnaya, Larisa G, Roman Kuchta, Bristow, Glenn A, and Tomáš Scholz
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- skenovací elektronová mikroskopie, transmisní elektronová mikroskopie, fylogeneze, scanning electron microscopy, transmission electron microscopy, phylogeny, basal cestodes, ultrastructural characters, 2, and 59
- Language:
- English
- Description:
- Using scanning and transmission electron microscopy, ultrastructure of the anterior organ and posterior funnel-shaped canal of Gyrocotyle urna Wagener, 1852 (Cestoda: Gyrocotylidea) from ratfish, Chimaera monstrosa (Holocephali), was studied for the first time. The proper anterior organ is localised at a short distance (about 170 µm) from an apical pore surrounded by a receptor field, whereas its distal end is marked by a muscular sphincter. The tegumental surface of this organ is covered with short filitriches of irregular length; large area of muscle layers traverse beneath the tegumental layer. The funnel-shaped canal of G. urna (2.5-3.0 mm long) is a specialised, muscular part of the posterior attachment organ; it opens on the rounded elevation on the dorsal body surface. The tegumental layer bears conical sclerite-like structures (up to 1.5 µm long). It produces electron-dense bodies that are transported into a canal lumen and surrounded thick muscle area mixed with numerous nerve fibres. The present ultrastructural study of G. urna indicates that gyrocotylideans share some ultrastructural characters of the anterior organ with spathebothriidean cestodes with a single anterior attachment sucker-like organ. In contrast, the unique posterior rosette attachment organ with funnel-shaped canal of the Gyrocotylidea resembles the haptor of polyopisthocotylean monogeneans in its position at the posterior end of the body and presumed origin. The above-mentioned features add more clarity to support the basal position of the Gyrocotylidea Poche, 1926 among cestodes. In addition, they also indicate a possible relationship of gyrocotylidean ancestors with monogeneans., Larisa G. Poddubnaya, Roman Kuchta, Glenn A. Bristow, Tomáš Scholz., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
254. Ultrastructure of the spermatozoon of the trematode Notocotylus noyeri (Digenea: Notocotylidae), a parasite of Microtus arvalis (Rodentia: Cricetidae)
- Creator:
- Ndiaye, Papa Ibnou, Torres, Jordi, Eira, Catarina, Shimalov, Vladimir V, and Miquel, Jordi
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- ploštěnci, cytochemie, Platyhelminthes, cytochemistry, Pronocephaloidea, sperm characters, TEM, 2, and 59
- Language:
- English
- Description:
- In the present paper, we describe the ultrastructure of the spermatozoon of the notocotylid Notocotylus noyeri (Joyeux, 1922) by means of transmission electron microscopy. The mature spermatozoon of N. noyeri exhibits the general pattern described in the majority of digeneans: two axonemes of the 9 + "1" pattern of the Trepaxonemata, nucleus, mitochondria, parallel cortical microtubules, spine-like bodies and ornamentation of the plasma membrane. The glycogenic nature of the electron-dense granules was evidenced applying the test of Thiéry. The ultrastructural features of the spermatozoon of N. noyeri present some differences in relation to those of the Pronocephalidea described until now, but confirm a general pattern for the Notocotylidae, namely a spermatozoon with two mitochondria and an anterior region with ornamentation of the plasma membrane associated with spine-like bodies. The posterior extremity of the spermatozoon exhibits only some microtubules after the disorganisation of the second axoneme. The present study confirms that some ultrastructural characters of the sperm cell such as the presence or absence of lateral expansions, the number of mitochondria and the morphology of both anterior and posterior spermatozoon extremities are useful for phylogenetic purposes within the Pronocephaloidea. Thus, unlike notocotylids, pronocephalids exhibit external ornamentation and a lateral expansion in the anterior spermatozoon region. Moreover, notocotylid spermatozoa present two mitochondria, whereas pronocephalid spermatozoa exhibit a single mitochondrion. Finally, pronocephalids are characterised by a type 2 posterior spermatozoon extremity, whereas notocotylids exhibit a type 3 posterior spermatozoon extremity., Papa Ibnou Ndiaye, Jordi Torres, Catarina Eira, Vladimir V. Shimalov, Jordi Miquel., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
255. Určení redakce staročeské bible Záblackého
- Creator:
- Pečírková, Jaroslava
- Format:
- electronic
- Type:
- model:article and TEXT
- Subject:
- Old Czech Bible, Záblacký Bible, BL, Z004, and P1
- Language:
- Multiple languages
- Description:
- Our comparison of samples from the Záblacký Bible with the first, second and third editions of the Old Czech Bible translation confirms Kyas's classification of the Záblacký Bible as a compilation translation, containing parts with texts from different editions of the Old Czech Bible. Some of its books belong to the first edition of the Old Czech Bible translation, some to the second, or the first and the second edition against the third edition, and some indicate conformity to third edition bibles. Some parts show conformity with the second and simultaneously the third editions against the first edition. In some places the Záblacký Bible even has its own reading, which we have not found in any other bible that we have worked with.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
256. Určení redakce staročeské bible Záblackého
- Creator:
- Pečírková, Jaroslava
- Format:
- electronic
- Type:
- model:article and TEXT
- Subject:
- Old Czech Bible, Záblacký Bible, Z004, P1, and BL
- Language:
- Multiple languages
- Description:
- Our comparison of samples from the Záblacký Bible with the first, second and third editions of the Old Czech Bible translation confirms Kyas's classification of the Záblacký Bible as a compilation translation, containing parts with texts from different editions of the Old Czech Bible. Some of its books belong to the first edition of the Old Czech Bible translation, some to the second, or the first and the second edition against the third edition, and some indicate conformity to third edition bibles. Some parts show conformity with the second and simultaneously the third editions against the first edition. In some places the Záblacký Bible even has its own reading, which we have not found in any other bible that we have worked with.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
257. Úskalí on-line dotazování při měření postojů vysokoškoláků a pracovníků vysokých škol
- Creator:
- Ryšavý, Dan
- Format:
- electronic
- Type:
- model:article and TEXT
- Subject:
- CAWI, census, sampling, response-rate, statistical significance, EUROSTUDENT, and academic staff survey
- Language:
- Czech
- Description:
- This article presents a critical evaluation of the growing popularity of online social surveys for the exploration of attitudes and behaviours within higher educational institutions. More specifically this article addresses a number of key issues: the construction of representative online samples, and the presentation of the results from an institutional census constructed from an online survey with a low response rate. The improper use of statistical significance tests, and the reporting of systematic errors when quota sampling is employed in surveys is also discussed. This study compares and evaluates four recent academic surveys: (a) the Czech wave of the EUROSTUDENT IV survey fielded by SC&C, (b) A Research Survey on Academic Staff at Czech Colleges and Universities undertaken by SC&C in 2009, (c) surveys of students and (d) employees at Palacky University Olomouc undertaken by the newly established Laboratory of Social Research. This article shows that an improper interpretation of online surveys resulted in a missrepresention of the views of university students and academic staff on the state of Czech higher education and opinions concerning different tertiary education reform measures.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
258. Úvod do problematiky výzkumu citlivých témat ve výběrových šetřeních
- Creator:
- Chylíková, Johana
- Format:
- electronic
- Type:
- model:article and TEXT
- Subject:
- surveying in sociology, questionnaire, respondent, sensitivity, sensitive questions, social desirability, validity, measurement errors, and HM
- Language:
- Czech
- Description:
- The aim of this article is to provide an overview of the problems associated with the fielding of questions of a socially sensitive nature typically dealing with crime, health, and sexual activity in nationally representative sample surveys. This article presents an overview of previous research on this topic and associated themes such as the definition of sensitive survey questions, the emergence and impact of social desirability effects and application of the Cognitive Aspects of Survey Methodology (CASM) to mechanisms of question response on sensitive topics. Thereafter, this article maps out specific sources of error that are likely to occur when fielding sensitive survey questions; and highlights methods that may used to minimise measurement error, thereby enhancing data validity. The article concludes with an appraisal of some of the most influential criterion-validity used in this sub-field of survey research.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
259. Věcná významnost výsledků a její možnosti měření
- Creator:
- Soukup, Petr
- Format:
- electronic
- Type:
- model:article and TEXT
- Subject:
- substantive significance, effect size, economic significance, clinical significance, and HM
- Language:
- Czech
- Description:
- In this article it is argued that one of the main problems in data analysis is an over-emphasis on statistical rather than substantive significance. Statistical significance reports the improbability of specific outcomes from sample data using a null hypothesis. In contrast, substantive significance is concerned with the real-world meaning of data modelling results for a population, regardless of p value, where an effect size estimator is used for evaluation. The argument presented in this article begins with a consideration of how substantive significance may be defined. Thereafter, there is a summary of the literature on substantive significance and its measurement using a variety of effect size estimators, many of which are little known to researchers. This article also examines the topics of economic and clinical significance. In the conclusion, this study discusses attempts to synthesise different concepts of substantive significance and recommends some practical usage of these concepts.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
260. Vladimír Hudec: Zdeněk Fibich. Tematický katalog. Thematisches Verzeichnis. Thematic Catalogue, Editio Bärenreiter Praha, Praha 2001
- Creator:
- Gabrielová, Jarmila
- Format:
- electronic
- Type:
- model:article and TEXT
- Subject:
- ML
- Language:
- Czech
- Description:
- Review of Vladimír Hudec: Zdeněk Fibich. Tematický katalog. Thematisches Verzeichnis. Thematic Catalogue, Editio Bärenreiter Praha, Praha 2001, 850 stran + 17 faksimilovaných příloh.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public