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3. Field observations, laboratory rearing and descriptions of immatures of the planthopper Hyalesthes absoletus (Hemiptera: Cixiidae)

Creator:
Sforza, Bourgoin, Thierry, Wilson, Stephen W., and Boudon-Padieu, Elisabeth
Format:
print, text, and regular print
Type:
article, bibliography, model:article, and TEXT
Subject:
zoologie, entomologie, hmyz, Hemiptera, Cixiidae, Hyalesthes absoletus, stadium infarktu, morfologie, řádkovací elektronová mikroskopie, 595.2/.7, and 5915
Language:
English
Description:
The cixiid planthopper Hyalesthes obsoletus Signoret is an efficient vector of the stolbur phytoplasma, the cause of various crop diseases. In the field, this monovoltine species feeds on a wide variety of woody and herbaceous plants. It overwinters as larvae on the roots of its host plants. During this study, we collected adults mainly from lavender (Lavendula angustifolia Miller), bindweed (Convolvulus arvensis L. and C. sepium L.), hoary cress (Cardaria draba L.), and occasionally from plantain (Plantago cynops L.), toadflax (Linaria striata L.), bedstraw (Galium verum L.), and mountain savory (Satureia montana L.). Fertility of field collected females from sites at two different elevations differed significantly. Fertility at 300 m (50.6 eggs per female; N = 28) was more than twice that at 900 m (22.8 eggs per female; N = 19). Only one specimen of the species was found to be parasitized by an undetermined species of Dryinidae (Hymenoptera). H. obsoletus was reared in controlled conditions on lavender. Unlike in the field, larvae developed in the laboratory at the base of the host plant and on basal shoots. Egg incubation averaged 7 ± 1.2 weeks (N = 10). Total development time from egg to adult averaged 27 ± 4 weeks (N = 5) on lavender. A morphological description of the five instars is provided. The study was supplemented by scanning electron microscopy. Particular attention was paid to the structure of the wax-plates and the absence of compound eyes in the early larval stages., René Sforza, Thierry Bourgoin, Stephen W. Wilson, Elisabeth Boudon-Padieu, and Lit
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

5. Insemination and fertilization in the seed bug Lygaeus simulans (Heteroptera: Lygaeidae)

Creator:
Micholitsch, Thomas, Krügel, Peter, and Pass, Günther
Format:
print, text, and regular print
Type:
article, model:article, and TEXT
Subject:
Lygaeidae, kopulace, entomologie, hmyz, ploštice, Lygaeus simulans, kopulační orgány, morfologie, inseminace, fertilizace, Heteroptera, genitalia, copulation, cryptic female choice, sperm utilization, spermatheca, aedeagus, processus gonophori, insemination, fertilization, 595.2/.7, and 591.4
Language:
English
Description:
In the laboratory, not all females of the seed bug Lygaeus simulans Deckert, 1985, produced fertilized eggs after copulation: 26.7% of the females were not inseminated and 5% were inseminated but did not lay fertilized eggs; only in 40% of the couples did copulation result in fertile eggs. The remaining 28.3% of couples refrained from mating. Duration of copulation was associated with insemination and fertilization: (i) fertile eggs were produced by only one couple that copulated for less than 60 min and all those that copulated for more than 360 min, (ii) probability of fertilization increased steadily with duration of copulation between 60 and 360 min, and (iii) duration of copulation was significantly different for couples that showed different insemination status. A possible morphological explanation for this rime dependency was revealed by examining the genitalia of 69 couples freeze-fixed in copula after different periods in copulation. Because of the intricate structure of the genitalia in L. simulans, a male takes a long time to manoeuver its intromittent organ into the narrow insemination duct of the female. Only if completely inserted is the tip of the intromittent organ close enough for successful ejaculation of sperm into the spermatheca. The freeze-fixing experiment revealed that it usually took the male more than 30 min to locate the entrance to the insemination duct and another 30 min for full penetration. This explains why copulations that lasted less than 60 min failed, since insemination began only after intromission was complete. The experiments, therefore, indicated that there is a relationship between the complex morphology of the genitalia and the low rates of insemination and fertilization in L. simulans., Thomas Micholitsch, Peter Krügel, Günther Pass, 7 obrázků, 1 tab., and Lit.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

6. Jednoznačnost a kontext: kvantitativní studie

Creator:
Cvrček, Václav and Václavík, Jiří
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
context disambiguation, corpus, lemma, word-form, morphology, kontextová disambiguace, korpus, slovní tvar, and morfologie
Language:
Czech
Description:
General consensus in linguistics is that language context (or ''co-text'') plays crucial role in describing linguistic properties of language items. Isolated units are, as a corollary to this statement, inherently ambiguous (polysemous and/or polyfunctional). In this paper we describe the most influential forces leading to disambiguation of language units, specifically the role of n-gram length on its ambiguity.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

7. K vývoji raně gotických hranatých profilů okenních kružeb /

Creator:
Kroupa, Pavel,
Type:
text and studie
Subject:
Architektura, architektura raně gotická, architektura sakrální, okna, morfologie, kostely, kláštery, světové dějiny středověku (do r. 1492), české země 1197-1306, architektura, architekti, and církevní architektura, hmotné památky, hřbitovy a poutní místa
Language:
Czech
Description:
Zur Entwicklung der frühgotischen kantigen Profile von Fenstermaßwerken.
Rights:
unknown

8. Kak bedra bedrom stala. Rekonstrukcija praslavjanskogo nazvanija bedra (na materiale pamjatnikov XI-XIV vv.) /

Creator:
Sajenko, Michail Nikolajevič
Type:
text and studie
Subject:
Slovanské jazyky, dějiny jazyka, jazyk praslovanský, jazyk církevněslovanský, morfologie, rukopisy, světové dějiny středověku (do r. 1492), české země 1197-1306, české země 1306-1419, and jazyk, písmo
Language:
Russian
Description:
How 'bedra' Turned into 'bedro'. Reconstruction of the Proto-Slavic Term for 'Hip' (Based on the Data of the 11th to 14th Century Texts).
Rights:
unknown

9. Keramická produkce z Prahy a jejího širšího zázemí v raném a na počátku vrcholného středověku /

Creator:
Boháčová, Ivana,
Type:
text and studie
Subject:
Archeologie, keramika středověká, archeologie, nálezy, středověk raný, středověk vrcholný, chronologie, morfologie, české země od příchodu Slovanů do roku 1306, and hmotná kultura, umělecká řemesla
Language:
Czech
Description:
Pottery production from Prague and its wider hinterland in the Early and the beginning of the High Middle Ages.
Rights:
unknown

10. Kontextová analýza a systém slovních druhů

Creator:
Cvrček, Václav
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
context analysis, corpus-driven approach, morphology, parts of speech, kontextová analýza, corpus-driven přístup, morfologie, and slovní druhy
Language:
Czech
Description:
The most influential achievement of corpus linguistics lies in the growing importance of context in the description of language. This is also reflected by context analysis which is introduced in this paper. Context analysis is an umbrella term for a bundle of methods sharing the same hypothesis: that all the features (form, meaning, function) of the language phenomena are mirrored by the context which they enter. It is important to emphasise that by the term ''context'', it is meant here not only one or two adjacent tokens in a particular text, but all the neighbouring units (e.g. words, lemmas, part of speech tags etc.) which co-occur with a given word in all of its instances in a corpus. The paper discusses various types of context (range, type of contextual units etc.) and their effect on the analysis. By comparing contexts of distinct words or word groups we may find out what the similarities and differences are between language units, phenomena or even groups of lexemes. This type of research was conducted here to determine the relations between parts of speech.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public