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21422. Spatial navigation: implications for animal models, drug development and human studies
- Creator:
- Aleš Stuchlík, Kubik, S., Kamil Vlček, and Karel Valeš
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, paměť, učení, navigace, mozek, neurony, memory, learning, navigation, brain, neurons, spatial representation, moving environments, rats, animal models, 14, and 612
- Language:
- English
- Description:
- Spatial navigation and memory is considered to be a part of the declarative memory system and it is widely used as an animal model of human declarative me mory. However, spatial tests typically involve only static settings, despite the dynamic nature of the real world. Animals, as well as people constantly need to interact with moving objects, other subjects or even with entire moving environments (flowing water, running stairway). Therefore, we design novel spatial tests in dynamic environments to study brain mechanisms of spatial processing in more natural settings with an interdisciplinary approach including neuropharmacology. We also translate data from neuropharmacological studies and animal models into development of novel therapeutic approaches to neuropsychiatric disorders and more sensitive screening tests for impairments of memory, thought, and behavior., A. Stuchlik ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
21423. Spaziergang nach Lützschena und dessen Umgebungen: Ein Wegweiser für Freunde der Natur, Kunst und Landwirthschaft
- Creator:
- Speck-Sternburg, Maximilian Freiherr von
- Publisher:
- B. G. Teubner
- Format:
- print, text, regular print, and 51 s., 13 obr. příl. ; 8°
- Type:
- model:monograph and TEXT
- Subject:
- 502.2, 904, 631, 025.171, 502, 2, 094.5, 12, příroda, přírodní podmínky, kulturní památky, zemědělství, Životní prostředí a jeho ochrana, and Tisky (19. století)
- Language:
- German
- Description:
- Converted from MODS 3.5 to DC version 1.8 (EE patch 2015/06/25)
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
21424. Special issue in memory of František Matúš
- Creator:
- Ay, Nihat and Studený, Milan
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- 23 and 007
- Language:
- English
- Description:
- Nihat Ay and Milan Studený.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
21425. Speciální ochranné pomůcky pro intervenční radiologii - první zkušenosti
- Creator:
- Daníčková, Kateřina, Pádr, Radek, Chmelová, Daša, and Roček, Miloslav
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, and TEXT
- Subject:
- intervenční radiografie--metody--přístrojové vybavení, radiační ochrana--metody, ochranné prostředky, rukavice ochranné, chirurgické krycí roušky, dávka záření, lékaři, pilotní projekty, and lidé
- Language:
- Czech and English
- Description:
- Cíl: Výkony intervenční radiologie patří ve spektru radiologických metod k dávkově nejnáročnějším. Pro snížení radiační zátěže jsou na trhu k dispozici i speciální pomůcky pro další snížení dávek, zejména na ruce. Jsou to jednorázové sterilní roušky, které se přikládají na pacienta a slouží jako ochrana před rozptýleným zářením z pacienta nebo sterilní ochranné rukavice určené přímo pro intervenujícího radiologa. Publikované klinické studie slibují významnou dávkovou úsporu (90%). Cílem pilotní studie bylo ověřit skutečnou účinnost těchto typů ochranných pomůcek v podmínkách klinické praxe. Metodika: Do prvotní studie byly zařazeny tři prováděné druhy intervenčních výkonů. Při probíhajícím vyšetření byla měřena kumulativní dávka na ruce (fyzikální veličina Hp (0,07)) za celý výkon a následně normalizována celkovým skiaskopickým časem daného výkonu. K měření byl použit přímo odečítající dozimetr Unfors EDD 30. Do studie bylo pro každý typ vyšetření zařazeno 20 pacientů a následně rozděleno do podskupin podle typu použité ochranné pomůcky. Výsledky: Z naměřených dat je patrné, že nejúčinnější ochrannou pomůckou pro sledované typy výkonů je jednoznačně rouška (snížení až o 85-89 %). Rukavice dávku radiologa snižují o 44-68 %. Závěr: Oba typy ochranných pomůcek mají velký potenciál pro snižování radiační zátěže rukou intervenčních radiologů. K tomuto účelu je ale nutné jejich správné použití a úzká spolupráce radiologa a radiologického asistenta., Aim: Interventional radiology is in the spectra of radiological procedures the most challenging from the radiation protection view. Among standard protective equipment, there are tools available for reducing dose impact on radiologists hands - sterile disposable pads to be placed on the patient to shield the scattered radiation comming from the patient or protective gloves for the interventionalist. Published clinical trials promise significant dose savings (90%). The aim of our pilot study was to verify the true effectiveness of these types of protective equipment under clinical practice. Methods: The initial study was carried out for three types of interventional procedures. Cumulative dose (physical quantity Hp (0.07)) for the whole procedure was subsequently normalized by total fluoroscopy time of the procedure. For dose measurements direct dosimeter Unfors EDD 30 was used. Our study was included 20 patients for each type of procedure. Obtained data were divided into subgroups according to the type of protective equipment used. Results: The results are provided for better clarity in graphs. Data show that the most effective protective equipment for the monitored types of procedures is pad (reduction of up to 85-89%). Gloves have reduced the dose to radiologists hands by 44-68%. Conclusion: Both types of protective devices have great potential for reducing radiation dose on fingers, but only when properly used. For this purpose, close cooperation among interventional radiologists and radiographers is essential., Kateřina Daníčková, Radek Pádr, Dáša Chmelová, Miloslav Roček, and Literatura
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
21426. Species at the edge of their range: The significance of the thermal environment for the distribution of congeneric Craspedolepta species (Sternorrhyncha: Psylloidea) living on Chamerion angustifolium (Onagraceae)
- Creator:
- Bird, Jeremy M. and Hodkinson, Ian D.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, conference publication, model:article, and TEXT
- Subject:
- Third European Workshop of Invertebrate Ecophysiology (1998 : Birmingham, Česko), zoologie, fyziologie živočichů, ekofyziologie, hmyz, Psylloidea, Craspedolepta nebulosa, Craspedolepta subpunctata, výskyt, rozšíření, životní cyklus, fenologie, ekologické faktory, teplota, sezónní vlivy, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- There is much current discussion about the factors that control the distribution and abundance of animal species, particularly at the edges of their range. The significance of temperature for survival and development is compared in two closely related psyllid species (Craspedolepta nebulosa and C. subpunctata) living on the same host plant (Chamerion angustifolium) (Onagraceae) but displaying different distributions along latitudinal and altitudinal gradients. The following measurements were made at critical periods during the life cycle (a) winter supercooling points (SCPs), (b) tolerance of short (1 min) and long term (1-25) days exposure to sub-zero temperatures above the SCP, (c) tolerance of short term exposure to high spring/summer temperatures and (d) comparative field development rates among species and sites during the early critical part of the growing season. Successful completion of the life cycle is related to heat availability during the growing season. This appears to limit the distribution of the Craspedolepta species, rather than their survival response to thermal extremes. No significant differences were found between the two species in the supercooling point or in their long and short term survival responses at low or high temperatures., Jeremy M. Bird, Ian D. Hodkinson, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
21427. Species specific diurnal changes in chlorophyll fluorescence in tropical deciduous and evergreen plants growing in the field during summer
- Creator:
- Joshi, S.C.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Acer, Aesculus, Bauhinia, Boehmeria, Celtis, Dalbergia, Eugenia, Ficus, Grewia, and Sapium
- Language:
- Multiple languages
- Description:
- Diumal changes in chlorophyll (Chl) a fluorescence characteristics of sun-exposed and shade leaves of some tropical and temperate tree species growing under fíeld conditions on sunny and cloudy days during summer were recorded. Significant reduction in photochemical efficiency of photosystem (PS) 2 measured as ratio during periods of maximum irradiance was observed in sun-exposed leaves of some plants. The extent of this reduction was probably a function of the plant species. Among the tropical species tested, Boehmeria rugulosa, Celíis ausíralis, Dalbergia sissoo, Eugenia jambolana and Grewia optiva showed maximum reduction (15-22 %), whereas species like Ficus racemosa and Sapium sebiferum showed least dechne (< 7 %) in the F^/F^ ratio. On the other hand, no significant reduction in this ratio was observed in Bauhinia purpurea. Temperate species, v/z. Acer oblongum and Aesculus indica, were most susceptible to high irradiances. Prolonged exposure of these plants to high irradiances resulted in lesion development in their leaves characterized by reduction in pigment contents and Fy/F^, ratio. Plant species with considerable midday dechne in Fy/Fn, ratio showed (7) slight but significant rise in initial fluorescence (Fq), (2) pronounced decrease in F^ value, and (3) significant reduction in area over the curve between Fq and Fj„ indicating the pool size of electron acceptors on the reducing side of PS2. The depression in Fy/F^ ratio though reversible could not be alleviated even after watering the plants at hourly intervals. No reduction in Fy/F^, was observed in shade leaves of the same plants and/or when measurements were taken on cloudy days. Hence high solar radiation and high atmospheric evaporative demand existing during summer period could probably be the major contributoiy factors for this reduction.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
21428. Specific leaf area variations drive acclimation of Cistus salvifolius in different light environments
- Creator:
- Puglielli, G., Varone, L., Gratani, L., and Catoni, R.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- karotenoidy, carotenoids, aklimatizace, acclimatization, fluorescence chlorofylu, výměna plynu, absorptance listu, Cistus salvifolius, list, chlorophyll fluorescence, gas exchange, leaf absorptance, leaf nitrogen partitioning, leaf, 2, and 581
- Language:
- Multiple languages
- Description:
- Cistus salvifolius L. is the most widely spread Cistus species around the Mediterranean basin. It colonizes a wide range of habitats growing from sea level to 1,800 m a.s.l., on silicolous and calcicolous soils, in sun areas as well as in the understory of wooded areas. Nevertheless, this species has been mainly investigated in term of its responsiveness to drought. Our aim was to understand which leaf traits allow C. salvifolius to cope with low-light environments. We questioned if biochemical and physiological leaf trait variations in response to a reduced photosynthetic photon flux density were related to leaf morphological plasticity, expressed by variations of specific leaf area (SLA) and its anatomical components (leaf tissue density and thickness). C. salvifolius shrubs growing along the Latium coast (41°43'N,12°18'E, 14 m a.s.l., Italy) in the open and in the understory of a Pinus pinea forest, were selected and the relationships between anatomical, gas exchange, chlorophyll (Chl) fluorescence, and biochemical parameters with SLA and PPFD variations were tested. The obtained results suggested long-term acclimation of the selected shrubs to contrasting light environments. In high-light conditions, leaf nitrogen and Chl contents per leaf area unit, leaf thickness, and Chl a/b ratio increased, thus maximizing net photosynthesis, while in shade photosynthesis, it was downregulated by a significant reduction in the electron transport rate. Nevertheless, the increased pigment-protein complexes and the decreased Chl a/b in shade drove to an increased light-harvesting capacity (i.e. higher actual quantum efficiency of PSII). Moreover, the measured vitality index highlighted the photosynthetic acclimation of C. salvifolius to contrasting light environments. Overall, our results demonstrated the morphological, anatomical, and physiological acclimation of C. salvifolius to a reduced light environment., G. Puglielli, L. Varone, L. Gratani, R. Catoni., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
21429. Specific metabolic characteristics of women with former gestational diabetes: the importance of adipose tissue
- Creator:
- Daniela Vejražková, Marie Vaňková, Petra Lukášová, Josef Včelák, Veronika Cirmanová, Martin Haluzík, and Běla Bendlová
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, tuková tkáň, adipose tissue, breastfeeding, gestational diabetes mellitus, insulin sensitivity, adipokines, 14, and 612
- Language:
- English
- Description:
- Women with a positive history of gestational diabetes mellitus (GDM) face a higher risk of developing type 2 diabetes mellitus (T2DM) and metabolic syndrome later in life. The higher risk of these metabolic complications is closely associated with adipose tissue. In this review, the importance of adipose tissue is discussed in relation to GDM, focusing on both the quantity of fat deposits and the metabolic activity of adipose tissue in particular periods of life: neonatal age, childhood, adolescence, and pregnancy followed by nursing. Preventive measures based on body composition and lifestyle habits with special attention to the beneficial effects of breastfeeding are also discussed., D. Vejrazkova, M. Vankova, P. Lukasova, J. Vcelak, V. Cirmanova, M. Haluzik, B. Bendlova., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
21430. Specific photosynthetic and morphological characteristics allow macroalgae Gloiopeltis furcata (Rhodophyta) to survive in unfavorable conditions
- Creator:
- Huan, L., Gao, S., Xie, X. J., Tao, W. R., Pan, G. H., Zhang, B. Y., Niu, J. F., Lin, A. P., He, L. W., and Wang, G. C.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, morfologie (biologie), photosynthesis, morphology (biology), cyclic electron flow, desiccation, Dual-PAM, salinity, Gloiopeltis furcata, Rhodophyta, 2, and 581
- Language:
- Multiple languages
- Description:
- Gloiopeltis furcata (Postels & Ruprecht) J. Agardh, a macroalga, which grows in an upper, intertidal zone, can withstand drastic environmental changes caused by the periodic tides. In this study, the photosynthetic and morphological characteristics of G. furcata were investigated. The photosynthetic performance and electron flows of the thalli showed significant variations in response to desiccation and salinity compared with the control group. Both PSII and PSI activities declined gradually when the thalli were under stress. However, the electron transport rate of PSI showed still a low value during severe conditions, while the rate of PSII approached zero. Furthermore, PSI activity of the treated thalli recovered faster than PSII after being submerged in seawater. Even though the linear electron flow was inhibited by DCMU [3-(3, 4-dichlorophenyl)-1,1-dimethylurea], the cyclic electron flow could still be restored. The rate of cyclic electron flow recovery declined with the increasing time of dark treatment, which suggested that stromal reductants from starch degradation played an important role in the donation of electrons to PSI. This study demonstrated that PSII was more sensitive than PSI to desiccation and salinity in G. furcata and that the cyclic electron flow around PSI played a significant physiological role. In addition, G. furcata had branches, which were hollow inside and contained considerable quantities of funoran. These might be the most important factors in allowing G. furcata to adapt to adverse intertidal environments., L. Huan, S. Gao, X. J. Xie, W. R. Tao, G. H. Pan, B. Y. Zhang, J. F. Niu, A. P. Lin, L. W. He, G. C. Wang., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public