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Start Over Coverage 27-34

2. Effect of plant population densíty on canopy net photosynthesis and their relation to graín yield in maize cultivars

Creator:
Dong, Shu-ting and Hu, Chang hao
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
Field experiments were conducted to explore the relationship between canopy apparent photosynthesis (F’N,can) ^nd grain yield of maize {Zea mays L.) and to determine over two years the effects of plant population density (PPD) on /'N.can- Yedan No. 4 hybrid (vertical leaf type) were grown at fíve PPD in 1989 and 1990. Measurements of /"n can were made throughout the growth period in a large plastic covered chamber put over a segment of the canopy. Maximum values of /^N.can ca. 1500 pmol(photon) m'^ s'* were about 2.8 mg(C02) m‘2(soil area) s'* at the anthesis stage and they decreased with age throughout grain filling. Differences in /^N can between PPD could be attributed to leaf area index (LAI) or radiant energy interception. There was a quadratic regression between and LAI. The critical LAI for Pn can was about 4 to 6 for Shendan No. 7 and Yendan 4, respectively. Grain yield also differed between PPD, the range was 850 to 1140 g m'^ in the two cultivars. Increasing PPD of Yedan No. 4 up to about 9 plants per m^ and decreasing PPD of Shendan No. 7 to about 4 plants per m^ in a non-stressed environment should increase grain yield. Pfj can anthesis was positively correlated with biological {r = 0.8750** to 0.9797**) and grain (r = 0.8932** to 0.9914**) yields.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Infection dynamics of the monogenean parasite Gyrodactylus gasterostei on sympatric and allopatric populations of the three-spined stickleback Gasterosteus aculeatus

Creator:
Raeymaekers, Joost A. M., Wegner, K. Mathias, Huyse, Tine, and Volckaert, Filip A. M.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Monogenea, Gyrodactylus gasterostei, ecological immunity, fish parasite, Gasterosteus aculeatus, host specificity, local adaptation, and parasite-host coevolution
Language:
English
Description:
Parasites with high host specificity maximally depend on their hosts, which should increase the likelihood of coevolution. However, coevolution requires reciprocal selection exerted by the host and the parasite, and thus a considerable level of parasite virulence. In species of the monogenean ectoparasite genus Gyrodactylus consecutive generations are confronted with a single host, which may constrain the evolution of virulence. Transmission, which is often important in the ecology of Gyrodactylus species, may have the opposite effect, but may also lead to the avoidance of coevolutionary arms races. We investigated the potential outcome of coevolution between Gyrodactylus gasterostei Gläser, 1974 and its host, the three-spined stickleback (Gasterosteus aculeatus L.) by determining the strength of genotype by genotype (G×G) interactions on two levels: within and between sympatric and allopatric host populations. To do so, we compared the parasite's infection dynamics on laboratory-reared sympatric (Belgian) and allopatric (German) hosts. We found that a parasite line successfully infected a range of sympatric host genotypes (represented by families), while it failed to establish on allopatric hosts. Phylogeographic studies suggest that neutral genetic divergence between the host populations cannot explain this dramatic difference. Provided that this result can be generalised towards other parasite lines, we conclude that coevolution in this host-parasite system is more likely to lead to local adaptation on the population level than to G×G interactions within populations.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Isometric composition operators on weighted Dirichlet space

Creator:
Han, Shi-An and Zhou, Ze-Hua
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
matematika, Dirichletova úloha, mathematics, Dirichlet problem, composition operator, weighted Dirichlet space, isometry, 13, and 51
Language:
English
Description:
We investigate isometric composition operators on the weighted Dirichlet space {D_\alpha } with standard weights {(1 - {\left| z \right|^2})^\alpha },\alpha > - 1 . The main technique used comes from Martín and Vukotić who completely characterized the isometric composition operators on the classical Dirichlet space D. We solve some of these but not in general. We also investigate the situation when {D_\alpha } is equipped with another equivalent norm., Shi-An Han, Ze-Hua Zhou., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

5. Koncovka -ě v dativu a lokálu plurálu desubstantivních adjektiv typu otcův a matčin

Creator:
Kopáčková, Lucie
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
desubstantive adjective, type otcův, type matčin, suffix -ův, suffix -in, mixed declination, the ending -ě, dative plural, local plural, desubstantivní adjektivum, typ otcův, typ matčin, sufix -ův, sufix -in, smíšená deklinace, koncovka -ě, dativ plurálu, and lokál plurálu
Language:
Czech
Description:
This article describes the presence of the ending -ě in dative and local plural of desubstantive adjectives of the type otcův and matčin in the present-day written Czech (for example: ke Klausově odpůrcům; podlehl matčině prosbám; o Henriettině úspěších; na soupeřově hřištích etc., instead of ke Klausovým odpůrcům; podlehl matčiným prosbám; o Henriettiných úspěších; na soupeřových hřištích etc.). These occurrences describe none of Czech Grammars. The research is based on language data extracted from the corpora SYN version 5. So, this article brings not only the information about their frequency and their text type distribution in the present-day written Czech, but also pays more attention to their tagging in the corpora.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

6. Konštrukcia plánovaného rodičovstva v období štátneho socializmu v bývalom Československu

Creator:
Potančoková, Michalela
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
family planning, attitudes towards contraception, and pre-1989 Czechoslovakia
Language:
Czech
Description:
The analysis deals with the discourse on family planning and contraception in the former Czechoslovakia during the 1970s and 1980s. Family planning became a topic at the beginning of the 1970s, nearly 30 years after the legalisation of the liberal abortion law. Induced abortion was introduced without any public discussion and before the introduction and spreading of effective contraception. Family planning was understood mainly as limitation of the family size to desired number of children. Although the timing of conception is also mentioned, in reality it was not possible due to problematic access of young women to effective contraception. Instead of promoting contraception, experts propagated abstaining from sexual intercourse in order to limit the risk of unwanted pregnancy, induced abortion and lowering age at sexual debut. Contraception was seen as a potential threat to traditional sexual norms, which institutionalised sexuality into marriage and made a double moral eligible. Low use of modern contraception has to be seen in the light of its difficult accessibility, a lack of information, low quality of especially hormonal contraceptives and attitudes of gynaecologists inhibiting the use of intrauterine and hormonal contraception among single childless and young women, since it was perceived as a risk to their fertility and a means of spreading promiscuity. In terms of ideology, contraception was seen as a threat to population growth.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

8. Zu Besonderheiten deutscher Redewendungen in der Jugendsprache

Creator:
Sternkopf, Jochen
Format:
print
Type:
model:internalpart and TEXT
Language:
English and Czech
Description:
Příspěvek je věnován problematice jazyka mládeže. Zkoumaná slovní spojení, vybraná ze dvou slovníků, jsou posuzována z hlediska syntaktického (např. utváření nových obratů podle již existujícího vzoru), sémantického a komunikačního (slova nabývající nový význam jsou často začleňována do ustálených větných forem a postupně se stávají frazeologismy). Samotný jazyk mládeže je pak posuzován jako specifická varieta řečové komunikace.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public