Analysis of the contents and organization of pigments in leaves of more than 60 plant species from different natural habitats revealed that the majority of plants from extreme regions had a low pigment content. The arctic plants contained 40-60 % less chlorophyll (Chl) than the same species in the temperate zone. The desert plants had an extremely low pigment content. Owing to high amount of total carotenoids (Car), the arctic and high montane plants had the lowest ratios Chl/Car. The part of Chl belonging to light-harvesting (LH)-antenna varied less than the total amounts. The majority of investigated arctic plants had a smaller amount of Chl and larger part of it in the LH-antenna than plants of the temperate zone. The pigment apparatus of high montane plants was distinguished by very high Car content probably serving as protectant against photodamage: in their photosystems 1 and 2 there was 4-5 times more p-carotene than in the plants of other zones.
Gendered practices in social work have never before been the subject of research in the Czech Republic. This article looks at gender perceptions and stereotypes in social work practices. It contains a discussion of some findings from a recent qualitative study of a social work organization. The research set out to explore the gendered constructions of women and men as clients. Data were collected from in-depth interviews with social workers. The conclusion of research is that women are constructed as responsible for protection, as cooperative, as subordinate and as hysterical, whereas men are constructed as outspoken, as uncooperative and as aggressive. The findings show the importance of raising the awareness of social workers about their gender strategies and the possible impact of these strategies on their professional work, Radka Janebová, Lucie Černá., and Obsahuje bibliografii
In the course of more than one hundred years of its existence, the sound recording became not only an important tool of ethnomusicological research, but also the factor of influence for the folk music. Forms of this relationship change together with the changes of the technical form of recording and reproduction and also with the changes of the attitude of society to these technologies. Roughly stated, there are three basic forms of relationship of folk music and sound recording. In the initial phase the sound recording - first on wax rolls - had been used for archivation of acoustic manifestations of folk music. Relatively early, however, folk music had been also spread and popularized by this means. This brought about also the influence of sound recording on mutual influencing of specific cultures and regions. The more and more accessible technologies of sound recording causes changes of the processes by which music is being passed down and taught. In the last decades, the sound recording had become also the means of music creation, a fact that manifests itself especially in various genres of contemporary electronic dance music.
Seasonal changes in water relations, net photosynthetic rate (PN), and fluorescence of chlorophyll (Chl) a of two perennial C3 deciduous shrubs, Ipomoea carnea and Jatropha gossypifolia, growing in a thorn scrub in Venezuela were studied in order to establish the possible occurrence of photoinhibition during dry season and determine whether changes in photochemical activity of photosystem 2 (PS2) may explain variations of PN in these species. Leaf water potential (ψ) decreased from -0.2 to -2.1 MPa during drought in both species. The PN decreased with ψ in I. carnea and J. gossypifolia by 64 and 74 %, respectively. Carboxylation efficiency (CE) decreased by more than 50 and 70 % in I. carnea and J. gossypifolia, respectively. In I. carnea, relative stomatal limitation (Ls) increased by 17 % and mesophyll limitation (Lm) by 65 % during drought, while in J. gossypifolia Ls decreased by 27 % and Lm increased by 51 %. Drought caused a reduction in quantum yield of PS2 (ϕPS2) in both species. Drought affected the capacity of energy dissipation of leaves, judging from the changes in the photochemical (qP) and non-photochemical quenching (NPQ) coefficients. Photoinhibition during drought in I. carnea and J. gossypifolia was evidenced in the field by a drop in the maximum quantum yield of PS2 (Fv/Fm) below 0.8 and also by non-coordinated changes in ϕPS2 and quantum yield of non-photochemical excitation quenching (Yn). Total soluble protein content on an area basis increased with ψ but the ribulose-1,5-bisphosphate carboxylase/oxygenase content remained unchanged. A reduction of total Chl content with drought was observed. Hence in the species studied photoinhibition occurred, which imposed an important limitation on carbon assimilation during drought. and W. Tezara ... [et al.].
Polovodičový pixelový detektor Timepix je novým členem rodiny Medipix. Konstrukčně se Timepix neodlišuje od svého předchůdce, kterým je detektor Medipix2. Každý pixel detektoru je i zde vybaven předzesilovačem, diskriminátorem a čítačem. Čítač je však možno v každém pixelu nastavit do jednoho ze tří režimů. Prvním režimem (čítač) je prosté počítání částic. Druhý režim (časovač) umožňuje stanovit dobu detekce částice. V tomto textu se zaměříme na využití posledního režimu (Wilkinsonův AD převodník), který dovoluje přímé měření energie detekovaných částic. Tato vlastnost otevírá mnoho možností využití. V článku se budeme věnovat zejména aplikacím v oboru energeticky citlivé radiografie., Jan Jakůbek, Andrea Cejnarová, Stanislav Pospíšil, Josef Uher., and Obsahuje bibliografii
Gangesia parasiluri Yamaguti, 1934 (Cestoda: Proteocephalidae) is redescribed on the basis of adults obtained from the intestine of Silurus asotus Linnaeus (Teleostei: Siluridae) from Lake Suwa, Nagano Prefecture, central Japan. Its life cycle was studied in the field and laboratory. Rostellar hooks of the adults showed a wide variation in number, ranging from 35 to up to 57. Plerocercoids were found in the rectum of Chaenogobius urotaenia (Hilgendorf) and Rhinogobius brunneus (Temminck et Schlegel) (Teleostei: Gobiidae) from the same lake. Procercoids were formed in the haemocoel of Mesocyclops leuckarti (Claus) (Copepoda: Cyclopidae) 7 days post infection at 21-25°C. They developed into plerocercoids in the intestine of Pseudorasbora puntila pumila Miyadi (Teleostei: Cyprinidae), R. brunneus and S. asotus. Plerocercoids from naturally and experimentally infected fishes were fed to S. asotus, from which immature worms were recovered. It is considered that the life cycle involves three hosts: a copepod as the intermediate host in which procercoids are formed, small fish as paratenic hosts which retain plerocercoids and transport them into S. asotus, and S. asotus as the definitive host in which adults develop. Rostellar hooks of the adults were much fewer, much larger and arranged in fewer circles than those of the plerocercoids. It is suggested that the former are newly formed and replace the latter in an early stage of development of plerocercoids into adults in 5. asotus.