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Статті в журналах з теми "Arctium – physiologie"

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Block, W., N. R. Webb, S. Coulson, I. D. Hodkinson, and M. R. Worland. "Thermal adaptation in the Arctic collembolan Onychiurus arcticus (Tullberg)." Journal of Insect Physiology 40, no. 8 (August 1994): 715–22. http://dx.doi.org/10.1016/0022-1910(94)90099-x.

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Dubatolov, V. V., and K. W. Philip. "Review of the northern Holarctic Arctia caja complex (Lepidoptera: Noctuidae: Arctiinae)." Canadian Entomologist 145, no. 2 (February 27, 2013): 147–54. http://dx.doi.org/10.4039/tce.2013.13.

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AbstractArctia olschwangi Dubatolov, formerly known only from Arctic Siberia, Russia, is recorded from northern Alaska, United States of America. Distinguishing characters between northern populations of Arctia brachyptera Troubridge and Lafontaine, Arctia caja (Linnaeus), A. olschwangi Dubatolov, and Arctia opulenta (Edwards) are discussed. Arctia brachyptera Troubridge and Lafontaine is hypothesised to be a subspecies of A. olschwangi Dubatolov but more specimens need to be examined before this taxonomic change is made.
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Behan-Pelletier, Valerie M. "CERATOZETIDAE OF THE WESTERN NORTH AMERICAN ARCTIC." Canadian Entomologist 117, no. 11 (November 1985): 1287–366. http://dx.doi.org/10.4039/ent1171287-11.

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AbstractThe Ceratozetidae of arctic western North America, represented by 12 species in 9 genera, are discussed. A new genus, Cyrtozetes, and species, Cyrtozetes denaliensis, are proposed, and Trichoribates copperminensis Hammer, T. polaris Hammer, Svalbardia paludicola Thor, Iugoribates gracilis Sellnick, Diapterobates notatus (Thorell) both adults and immatures, D. variabilis Hammer, Sphaerozetes arcticus Hammer, Fuscozetes sellnicki Hammer, Melanozetes longisetosus Hammer, and Ceratozetes spitsbergensis Thor and C. parvulus Sellnick are redescribed. Immatures of T. polaris, S. paludicola, F. sellnicki, and M. longisetosus are described. Distribution records of Ceratozetes gracilis (Michael) in the western North American arctic are listed. The new combination, Cyrtozetes shiranensis (Aoki and Fujikawa), is proposed.
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Anonymous, A. "2nd International Arctic Ungulate Conference." Rangifer 16, no. 2 (January 1, 1996): 49. http://dx.doi.org/10.7557/2.16.2.1196.

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The 2nd International Arctic Ungulate Conference was held 13-17 August 1995 on the University of Alaska Fairbanks campus. The Institute of Arctic Biology and the Alaska Cooperative Fish and Wildlife Research Unit were responsible for organizing the conference with assistance from biologists with state and federal agencies and commercial organizations. David R. Klein was chair of the conference organizing committee. Over 200 people attended the conference, coming from 10 different countries. The United States, Canada, and Norway had the largest representation. The conference included invited lectures; panel discussions, and about 125 contributed papers. There were five technical sessions on Physiology and Body Condition; Habitat Relationships; Population Dynamics and Management; Behavior, Genetics and Evolution; and Reindeer and Muskox Husbandry. Three panel sessions discussed Comparative caribou management strategies; Management of introduced, reestablished, and expanding muskox populations; and Health risks in translocation of arctic ungulates. Invited lectures focused on the physiology and population dynamics of arctic ungulates; contaminants in food chains of arctic ungulates and lessons learned from the Chernobyl accident; and ecosystem level relationships of the Porcupine Caribou Herd.
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Holmstrup, M., and L. Sømme. "Dehydration and cold hardiness in the Arctic Collembolan Onychiurus arcticus Tullberg 1876." Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology 168, no. 3 (April 7, 1998): 197–203. http://dx.doi.org/10.1007/s003600050137.

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Worland, M. R., G. Grubor-Lajsic, and P. O. Montiel. "Partial desiccation induced by sub-zero temperatures as a component of the survival strategy of the Arctic collembolan Onychiurus arcticus (Tullberg)." Journal of Insect Physiology 44, no. 3-4 (March 1998): 211–19. http://dx.doi.org/10.1016/s0022-1910(97)00166-2.

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PURAĆ, JELENA, DAVID W. POND, GORDANA GRUBOR-LAJŠIĆ, DANIJELA KOJIĆ, DUŠKO P. BLAGOJEVIĆ, MICHAEL ROGER WORLAND, and MELODY S. CLARK. "Cold hardening induces transfer of fatty acids between polar and nonpolar lipid pools in the Arctic collembollan Megaphorura arctica." Physiological Entomology 36, no. 2 (January 18, 2011): 135–40. http://dx.doi.org/10.1111/j.1365-3032.2010.00772.x.

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Scheiber, Isabella B. R., Brigitte M. Weiß, Margje E. de Jong, Anna Braun, Nico W. van den Brink, Maarten J. J. E. Loonen, Eva Millesi, and Jan Komdeur. "Stress behaviour and physiology of developing Arctic barnacle goslings ( Branta leucopsis ) is affected by legacy trace contaminants." Proceedings of the Royal Society B: Biological Sciences 285, no. 1893 (December 12, 2018): 20181866. http://dx.doi.org/10.1098/rspb.2018.1866.

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Natural populations are persistently exposed to environmental pollution, which may adversely impact animal physiology and behaviour and even compromise survival. Responding appropriately to any stressor ultimately might tip the scales for survival, as mistimed behaviour and inadequate physiological responses may be detrimental. Yet effects of legacy contamination on immediate physiological and behavioural stress coping abilities during acute stress are virtually unknown. Here, we assessed these effects in barnacle goslings ( Branta leucopsis ) at a historical coal mine site in the Arctic. For three weeks we led human-imprinted goslings, collected from nests in unpolluted areas, to feed in an abandoned coal mining area, where they were exposed to trace metals. As control we led their siblings to feed on clean grounds. After submitting both groups to three well-established stress tests (group isolation, individual isolation, on-back restraint), control goslings behaved calmer and excreted lower levels of corticosterone metabolites. Thus, legacy contamination may decisively change stress physiology and behaviour in long-lived vertebrates exposed at a young age.
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Nilssen, K. J., O. A. Gulseth, M. Iversen, and R. Kjol. "Summer osmoregulatory capacity of the world's northernmost living salmonid." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 272, no. 3 (March 1, 1997): R743—R749. http://dx.doi.org/10.1152/ajpregu.1997.272.3.r743.

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Anadromous Arctic charr (Salvelinus alpinus L.) were caught on their way to and from the sea with the use of a fish trap placed in the Dieset watercourse located on the Spitsbergen Island (79 degrees 10' Northern latitude) within the high-Arctic Svalbard archipelago. When subjected to a seawater challenge test (34 parts/thousand at 4-5 degrees C), charr on their way to the sea showed only minor and temporary changes in blood plasma osmolality and Na+ and Mg2+ concentrations. The seawater tests also revealed good hypoosmoregulatory capacity for Arctic charr returning from the marine environment 4 wk later. A progressive decrease in seawater tolerance was first documented 7-11 days after their return to the freshwater habitat. Thus the Svalbard charr, being the northernmost anadromous salmonid and probably a direct descendant from the first Salvelinus immigrants to freshwater systems, undergoes a preparatory increase of hypoosmoregulatory capacity (smoltification) before entering the oceanic water bodies. Furthermore, the termination of their short annual seawater stay is probably elicited by factors controlling body systems other than osmoregulation.
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Ma, Yi Long, Xiongwei Zhu, Patricia M. Rivera, Øivind Tøien, Brian M. Barnes, Joseph C. LaManna, Mark A. Smith, and Kelly L. Drew. "Absence of cellular stress in brain after hypoxia induced by arousal from hibernation in Arctic ground squirrels." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 289, no. 5 (November 2005): R1297—R1306. http://dx.doi.org/10.1152/ajpregu.00260.2005.

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Although hypoxia tolerance in heterothermic mammals is well established, it is unclear whether the adaptive significance stems from hypoxia or other cellular challenge associated with euthermy, hibernation, or arousal. In the present study, blood gases, hemoglobin O2 saturation (So2), and indexes of cellular and physiological stress were measured during hibernation and euthermy and after arousal thermogenesis. Results show that arterial O2 tension (PaO2) and So2 are severely diminished during arousal and that hypoxia-inducible factor (HIF)-1α accumulates in brain. Despite evidence of hypoxia, neither cellular nor oxidative stress, as indicated by inducible nitric oxide synthase (iNOS) levels and oxidative modification of biomolecules, was observed during late arousal from hibernation. Compared with rats, hibernating Arctic ground squirrels ( Spermophilus parryii) are well oxygenated with no evidence of cellular stress, inflammatory response, neuronal pathology, or oxidative modification following the period of high metabolic demand necessary for arousal. In contrast, euthermic Arctic ground squirrels experience mild, chronic hypoxia with low So2 and accumulation of HIF-1α and iNOS and demonstrate the greatest degree of cellular stress in brain. These results suggest that Arctic ground squirrels experience and tolerate endogenous hypoxia during euthermy and arousal.
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Дисертації з теми "Arctium – physiologie"

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Garros, Laurine. "Impact de conduites culturales innovantes sur la production de métabolites actifs pour la Cosmétique." Thesis, Orléans, 2021. http://www.theses.fr/2021ORLE3155.

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La valorisation de la richesse de la biodiversité régionale et la mise en place d’une démarche durable dans la production de bioactifs répond au besoin de l’industrie cosmétique dans un contexte réglementaire contraignant. Ce projet s’inscrit dans une démarche de valorisation du patrimoine végétal et de l’industrie locale de la région Centre-Val de Loire. Dans le cadre de ce projet, 13 plantes ou leurs co-produits issus de la biodiversité locale ou d’intérêt pour la filière horticole ont été sélectionnés et étudiés. Des tests in tubo ont été effectués sur les extraits de ces 13 plantes afin de mettre en évidence de potentielles activités antiâges contre des enzymes telles que la tyrosinase, l’élastase et la collagénase et/ou antioxydantes d’intérêt pour l’industrie cosmétique. Les résultats de ces tests ont permis de sélectionner une plante modèle ayant des activités différentes afin d’évaluer l’apport d’une élicitation sur l’augmentation de ses activités.Dans ce contexte, la réalisation de cultures classiques en hydroponie passive ou innovantes en hydroponie active ainsi qu’avec des cals in vitro avec des élicitations lumineuses grâce à des systèmes de lampe à LED de couleur bleue, rouge ou blanche a été effectuée sur la bardane (Arctium lappa L.). Chaque organe de la plante élicitée a été séparé et extrait aux ultrasons. La caractérisation de l’empreinte moléculaire de chaque extrait a été réalisée par chromatographie liquide couplée à de la spectrométrie de masse haute résolution (UHPLC-ESI-QTOF-HRMS/MS) afin d’identifier leur contenu et leur variabilité moléculaire en fonction de l’organe et/ou de l’élicitation étudié.Parallèlement, l’influence de l’élicitation sur les activités d’intérêt cosmétique particulièrement les activités anti-tyrosinase et anti-ROS a été évaluée
The valuing of regional biodiversity richness and the implementation of a sustainable approach in the production of bioactives meets the needs of the cosmetic industry in a restrictive regulatory context. This project is part of an approach to promote the plant heritage and local industry of the Centre-Val de Loire region. As part of this project, 13 plants or their co-products from local biodiversity or of interest for the horticultural industry were selected and studied. In tubo tests were carried out on the extracts of these 13 plants in order to highlight potential anti-aging activities against enzymes such as tyrosinase, elastase and collagenase and/or antioxidants of interest for the cosmetic industry. The results of these tests allowed the selection of a model plant with different activities in order to assess the contribution to an elicitation on the increase of its activities. In this context, the realization of classic cultures in passive hydroponics or innovative in active hydroponics as well as in vitro callus with light elicitations thanks to LED lamp systems of blue, red or white color was carried out onburdock (Arctium lappa L.). Each organ of the elicited plant was separated and extracted with ultrasound. The characterization of the molecular fingerprint of each extract was achieved by liquid chromatography coupled with high resolution mass spectrometry (UHPLC-ESI-QTOF-HRMS/MS) in order to identify their content and molecular variability according to the organ and/or elicitation studied. At the same time, the influence of the elicitation on the activities of cosmetic interest, particularly anti-tyrosinase and anti-ROS activities, was evaluated
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Moser, Jonathan G. "Cold Season Physiology of Arctic Plants." FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/750.

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The cold season in the Arctic extends over eight to nine months during which ecosystem gas exchange and water balance of arctic plants have been largely unexplored. The overall objective of this thesis was to examine two critical gaps in our knowledge about tundra cold season processes – ecosystem respiration at very low temperatures and water uptake during the winter-spring transition. I determined the temperature response of ecosystem respiration of tundra monoliths down to temperatures as low as can be expected under snow-covered conditions (-15 °C). Temperature responses fit the Arrhenius function well with Q10 values over the range of -15 to 15 °C varying from 6.1 to 4.8. I used deuterium-enriched water (2H2O) as a tracer to evaluate water uptake of evergreen plants at snowmelt when soils are largely frozen. The results revealed that evergreen plants take up water under snow cover, possibly via roots but undoubtedly by foliar uptake.
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Grigor, Jordan. "Ecology and physiology of chaetognaths (semi-gelatinous zooplankton) in Arctic waters." Doctoral thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27614.

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Les chaetognathes sont d’importants membres des communautés mésozooplanctoniques de l’Arctique en ce qui a trait à l'abondance et à la biomasse. Les chaetognathes de l’Arctique se répartissent en trois espèces principales qui sont considérées comme étant strictement carnivores : Eukrohnia hamata, Parasagitta elegans et Pseudosagitta maxima. Cette étude utilise un ensemble de données de filet planctoniques recueillies sur une période de 5 ans dans les régions européennes, canadiennes et de l'Alaska de l’Arctique (2007, 2008, 2012, 2013, 2014) et comprend un cycle annuel complet dans l'Arctique canadien (2007-2008), le but étant d’améliorer notre compréhension sur les distributions, les cycles de vie et les stratégies d'alimentation du E. hamata et du P. elegans. Dans la présente thèse, les points suivants seront abordés : (1) la stratégie d'alimentation et la maturité du P. elegans dans l'Arctique européen durant la nuit polaire en 2012 et 2013, (2) les cycles de croissance et de reproduction, les stratégies d'alimentation et les distributions verticales du E. hamata et du P. elegans dans l'Arctique canadien de 2007 à 2008, et (3) les différences spatiales dans les stratégies d'alimentation du E. hamata et du P. elegans à l'automne 2014. Afin d’étudier leurs stratégies d'alimentation, des analyses de contenu du tube digestif ainsi que des techniques biochimiques ont été utilisées. Dans l'Arctique canadien, le E. hamata et le P. elegans vivent tous deux pendant environ 2 ans. Le P. elegans colonise principalement les eaux épipélagiques, tandis que le E. hamata colonise principalement les eaux mésopélagiques. Dans cette région, P. elegans se reproduit en continue de l'été au début de l'hiver, dans la période de forte biomasse de copépodes, qui constituent ses proies, dans les eaux proches de la surface, un mode de reproduction basé sur l’apport immédiat d’énergie. Cependant, les résultats ont révélé que E. hamata a engendré des couvées distinctes dont on peut voir l’évolution au cours de fenêtres de reproduction séparées, à la fois durant les périodes de printemps-été et d’automne-hiver, ce qui suggère une reproduction basée sur les réserves. Les taux de prédation quotidiens évalués à partir des analyses du contenu du tube digestif sont généralement restés faibles pour les deux espèces de chaetognathes. Toutefois, pour E. hamata et P. elegans, les taux de prédation inférés en été-automne ont dépassé ceux de l’hiver-printemps. Des études d’alimentation ont révélé que E. hamata consomme de la matière organique particulaire (éventuellement des chutes de neige marine) tout au long de l'année, mais surtout en été, alors que le P. elegans se nourrit différemment. Les deux espèces sont caractérisées par une forte croissance estivale. La croissance hivernale du P. elegans était grandement restreinte, tandis que celle du E hamata l’était moindrement. En somme, les différences dans la façon dont les lipides et la neige marine sont utilisés par les deux espèces pourraient expliquer les différences dans leurs cycles de reproduction et leurs patrons de croissance saisonnière.
Chaetognaths are important members of Arctic mesozooplankton communities in terms of abundance and biomass. Despite this, the bulk of seasonal studies have focused on grazing copepods. Arctic chaetognaths comprise three major species which are thought to be strict carnivores: Eukrohnia hamata, Parasagitta elegans and Pseudosagitta maxima. This thesis uses datasets collected from plankton net sampling during five years in European, Canadian and Alaskan areas of the Arctic (2007, 2008, 2012, 2013, 2014) and includes a full annual cycle in the Canadian Arctic (2007-2008), the purpose being to improve our understanding of the distributions, life history and feeding strategies of E. hamata and P. elegans. The following topics are addressed: (1) the feeding strategy and maturity of P. elegans in the European Arctic during the polar night in 2012 and 2013; (2) the growth, breeding cycles, feeding strategies and vertical distributions of E. hamata and P. elegans, in the Canadian Arctic from 2007 to 2008; and (3) spatial differences in the feeding strategies of E. hamata and P. elegans in autumn 2014. To investigate feeding strategies, a combination of gut contents and biochemical techniques was used. In the Canadian Arctic, both E. hamata and P. elegans live for around 2 years. P. elegans mainly colonized epi-pelagic waters, whereas E. hamata mainly colonized meso-pelagic waters. In this region, P. elegans reproduced continuously from summer to early winter when copepod prey peak in near-surface waters. This is characteristic of income breeders. However, results for E. hamata revealed that this species spawned distinct and traceable broods during separate reproductive windows in both spring-summer and autumn-winter, suggesting capital breeding. Daily predation rates inferred from gut content analyses appeared to be generally low in the two chaetognath species, though inferred predation rates in summer-autumn exceeded those in winter-spring. Feeding studies revealed that E. hamata consumed particulate organic matter (possibly falling marine snow) throughout the year but especially in the summer, whereas P. elegans did not feed in this way. High summer growth seems to be a characteristic of both these species. Growth during winter was highly restricted in P. elegans, to a lesser extent in E. hamata. In summary, differences in how lipids and marine snow are utilised by the two species could explain differences in their breeding cycles and seasonal growth patterns.
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Shahsavarani, Arash. "Effects of temperature on embryonic physiology of Arctic char (Salvelinus alpinus)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0026/MQ51093.pdf.

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Blanar, Christopher A. "Growth, proximate composition and physiology of Arctic charr exposed to toxaphene and Diphyllobothrium dendriticum." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31197.

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The Arctic charr (Salvelinus alpinus) is a top predator in northern lakes and accumulates persistent lipophilic contaminants. Toxaphene, a major organochlorine contaminant in Arctic charr, is known to be acutely toxic to fish but the effects of dietary exposure have not been examined. Furthermore, lake-resident Arctic charr are frequently infected with larvae of the cestode, Diphyllobothrium dendriticum. The objective of this study was to investigate the effects of toxaphene exposure on Arctic charr growth, nutritional quality, physiology, and susceptibility to infections of D. dendriticum. A preliminary experiment found no effect of toxaphene on charr visceral organ and fat weights, plasma Vitamin A and E and plasma cortisol, although dominance hierarchies within groups may have masked treatment effects. For the main experiment, hatchery-reared Arctic charr were subjected to one of four treatments: (i) a single oral dose of corn oil (control); (ii) a single oral dose of 10 mug/g wet weight toxaphene dissolved in corn oil; (iii) exposure to 15 larval D. dendriticum; and (iv) a combination of both. (Abstract shortened by UMI.)
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McColl, Carolyn Julia. "The role of food, predation, and population density on the stress physiology of Arctic ground squirrels." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ34102.pdf.

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Belseth, Elen. "Eco-physiology of the Arctic kelp Laminaria solidungula : - using divers, Remotely Operated Vehicle and Pulse Amplitude Modulated fluorometry." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for biologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-16364.

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Morin, Philippe-Israël. "Acclimatation à la nuit polaire puis au retour de la lumière chez la diatomée arctique Fragilariopsis cylindrus." Master's thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27908.

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Durant l’hiver en Arctique, les algues de glace et le phytoplancton passent près de 6 mois à l’obscurité totale avant que les conditions pour la croissance soient optimales au printemps. Comment les algues polaires, composées principalement de diatomées, réussissent-elles à survivre à d’aussi longues périodes d’obscurité et à croître dès le retour de la lumière? Quels sont les mécanismes physiologiques impliqués? Les objectifs de l’étude présentée visent à caractériser l’état cellulaire d’une diatomée arctique, Fragilariopsis cylindrus, durant une période d’obscurité totale représentative de l’hiver polaire afin de mieux comprendre les mécanismes qui permettent la survie à l’obscurité prolongée et au retour de la lumière. Nous avons mesuré les mécanismes physiologiques impliqués en mesurant plusieurs paramètres à des intervalles précis: les premiers jours, les premières semaines et les trois premiers mois d’obscurité ainsi que les premières heures et les premiers jours des retours à la lumière après 1,5 et 3 mois d’obscurité. Les paramètres mesurés comprenaient le nombre et la taille des cellules, le carbone et l’azote particulaire, les lipides, la composition en pigments, la flurorescence variable, les protéines photosynthétiques (D1, RUBISCO), les paramètres photosynthétiques et le quenching non-photochimique (NPQ). Quelques jours après la transition à l’obscurité, Fragilariopsis cylindrus s’est acclimatée à un état stable qui s’est maintenu jusqu’au retour de la lumière. Cet état est caractérisé par un nombre et une taille des cellules stables, une faible consommation des réserves d’énergie, une faible diminution des pigments photosynthétiques et de très faibles capacités photosynthétiques. Après 1,5 mois d’obscurité, la réexposition à la lumière a déclenché une forte réponse du NPQ et un réassemblement de l’appareil photosynthétique, suivi d’une reprise des activités métaboliques et de la croissance cellulaire. La réexposition après 3 mois s’est caractérisée par une reprise des activités beaucoup plus lente, probablement causée par une mortalité plus importante.
Polar winter in the Arctic can last as long as 6 months each year at high latitude. During this period, no light is available for photoautotrophic growth. Nevertheless, when light returns in spring, a sea-ice algae and phytoplankton bloom develops in the surface ocean layers. Therefore, the following questions can be asked: How do photoautotrophic communities (mainly diatoms) survive through winter darkness until light returns in spring? What are the physiological mechanisms underlying such survival? Our goal was to understand the acclimation processes at stake in both darkness and during the return to light by closely looking at the changes in intra-cellular content and functional capacity of a polar sea-ice diatom, Fragilariopsis cylindrus. We measured a set of parameters at specific time-points: the first days and first weeks up to 3 months of darkness, and the first hours up to 6 days upon return to light. This set included cell number and cytometry, cellular carbon and nitrogen quotas, lipid and pigment contents, fluorescence determinations, photosynthetic proteins (D1, RUBISCO), photosynthetic parameters and non-photochemical quenching (NPQ). A rather stable state was reached few days following transition to dark and was maintained throughout until the return of light: stable cell size and number, low energy reserve consumption, slow decrease of photosynthetic pigments and very low photosynthetic capacities. Subsequent transition to light after 1.5 months induced strong NPQ activity and reassembly/renewal of photosynthetic components, followed by metabolic recovery and cell growth. Transition after 3 months showed a much slower recovery and no cell growth, highlighting the increase of potential mortality with longer periods of darkness.
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Hodinka, Brett. "Effect of Sleep Loss on Executive Function and Baseline Corticosterone Levels in an Arctic-Breeding Songbird, the Lapland Longspur (Calcarius Lapponicus)." TopSCHOLAR®, 2019. https://digitalcommons.wku.edu/theses/3130.

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Sleep is a fundamental and essential component of vertebrate life, although its exact function remains unknown. Animals that are deprived of sleep typically show reduced neurobiological performance, health, and in some cases, survival. However, a number of animals exhibit adaptations that permit them to carry out normal activities even when sleep is restricted or deprived. Lapland longspurs (Calcarius lapponicus), arctic-breeding passerine birds, exhibit around-the-clock activity during their short breeding season, with an inactive period of only 3–4 h/day (71°N). Whether these birds suffer behavioral and physiological costs associated with acute sleep loss (SL) is unknown. To assess the effects of SL, wild-caught male longspurs were placed in captivity (12L:12D) and trained for 2 months using a series of memory tests, including color association and spatial learning to assess executive function. Birds were then placed in automated sleep fragmentation cages that utilize a moving wire to force movement every 1 min (60 arousals/h) during 12D (inactive period) or control conditions (during 12L; active period). After a single round of SL (or control) treatment, color association and spatial learning tests were conducted. Baseline plasma corticosterone concentration, body mass, and satiety were also assessed. SL significantly elevated corticosterone levels and increased accuracy during the color association test, but not the overall time required to complete the test. SL had no effect upon spatial learning, body mass, or satiety. Taken together, these results suggest that Lapland longspurs exhibit a behavioral, but not a physiological, resilience to acute SL.
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10

Berg, Håkan. "Teleost reproduction: Aspects of Arctic char (Salvelinus alpinus) oocyte growth and maturation." Doctoral thesis, Umeå universitet, Molekylärbiologi (Teknat- och Medfak), 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-157.

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In all vertebrate species, reproduction is a hormonally controlled process, important for growth and maturation of gonads and germ cells. Production of functional germ cells is of outmost importance to secure the survival of a species. Fish comprises 50% of the known vertebrates and are found in aquatic habitats all over the world. Even though fish have evolved a wide variety of morphological and physiological characteristics, due to large differences in the living environment, the growth an maturation of germ cells follows the same pattern in all species. In this thesis the focus has been directed on oocyte growth and development in Arctic char (Salvelinus alpinus), and if stress might inflict disturbances on the reproductive systems. All sexually mature female egg laying vertebrates produces yolky eggs surrounded by an eggshell. Production of yolk and egg shell is under estrogenic control and it is known that production of egg components can be induced in male and juvenile fish by estrogenic substances. Many manmade chemicals have been found to interfere with hormonally controlled processes. Therefore production of the egg yolk precursor, vitellogenin (VTG), and the egg shell components, vitelline envelope proteins (VEP), have been used as biomarkers for estrogenic effect. Exposure to endocrine disrupting substances (EDS) does not only give rise to hormonal effects on the organism, but in addition it also gives rise to an increase in stress hormone, cortisol (F), levels. It is evident that a wide variety of substances may affect Arctic char oocyte growth and maturation. VTG and VEP production is found to be under dose dependent estrogenic control, but the production was directly affected by F. Under natural condition it has been found that F increases towards ovulation. Even though both VTG and VTG is under estrogenic control, these studies showed that stress lead to a decrease of VTG while the VEP production increased. These effects was only observed on protein levels indicating that a post transcriptional down regulation of VTG production is mediated by F in Arctic char. In order for an egg to become fertilizatible, it must undergo a maturation phase. This maturation phase is primarily induced by gonadotropins, which in turn induce the production of species specific maturation inducing substances (MIS). To investigate oocyte development in Arctic char a characterization of its MIS receptor was made. The MIS receptor is localized on the oocyte surface and displays a single class of high affinity and low capacity binding sites. The binding moieties displays association and dissociation kinetics typical of steroid membrane receptors. Even though high specificity for Arctic char MIS was observed, it was found that some EDS bind to the Arctic char oocyte membrane receptor. This suggest that certain EDS might affect oocyte maturation and thereby might alter the reproductive success. Furthermore, it was found that F did not bind to the MIS receptor in Arctic char. It is therefore suggested that oocytes are more sensitive to stress during the growth phase than during maturation
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Книги з теми "Arctium – physiologie"

1

McColl, Carolyn Julia. The role of food, predation, and population density on the stress physiology of arctic ground squirrels. Ottawa: National Library of Canada, 1998.

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2

M, Malinina G., ed. Osobennosti nespet͡s︡ificheskogo immuniteta u norok i pest͡s︡ov. Leningrad: "Nauka," Leningradskoe otd-nie, 1991.

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3

1940-, Rode A., ed. The health consequences of "modernization": Evidence from circumpolar peoples. Cambridge: Cambridge University Press, 1996.

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4

Kalinka, O. P., ed. Studies on ecosystems of theArctic: Proceedings of the XXXVII Conference for Young Scientists at MMBI KSC RAS. FRc KSC RAS, 2019. http://dx.doi.org/10.37614/978.5.91137.431.0.

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This publication contains papers submitted by young scientists at MMBI KSC RAS and their colleagues at the Murmansk Arctic State University and Murmansk State Technical University. The papers are devoted to hydrological and hydrochemical processes, sedimentation processes, spread of man-caused radionuclides, species composition and distribution of benthic organisms, physiology of brown seaweed, and behavior of marine mammals.
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5

Bennett, Valerie A. Ecological physiology of the Arctic woollybear caterpillar Gynaephora groenlandica (Lepidoptera: Lymantriidae). 2001.

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6

Kitchener, Andrew C., Carlo Meloro, and Terrie M. Williams. Form and function of the musteloids. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198759805.003.0003.

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The musteloids are the most speciose of the carnivorans and have a global distribution. They display a wide diversity of morphological and physiological form and function, which have been shaped by their adaptation to a wide variety of ecological niches, ranging from the Arctic to the tropics and deserts to the seas. This chapter explores how several morphological and physiological adaptations are key to their successful diversification, including an elongated body, a highly insulating pelage, powerful teeth and jaws, anal sacs for olfactory communication or chemical defence, and reproductive physiologies that allow females to optimise their reproductive output. While many of these adaptations are shared by other carnivorans, it is their combination in musteloids that has allowed them to diversify so successfully globally.
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7

(Editor), Hans-O. Pörtner, and Richard C. Playle (Editor), eds. Cold Ocean Physiology (Society for Experimental Biology Seminar Series). Cambridge University Press, 2007.

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8

Rode, Andris, and Roy J. Shephard. The Health Consequences of 'Modernisation': Evidence from Circumpolar Peoples (Cambridge Studies in Biological and Evolutionary Anthropology). Cambridge University Press, 1996.

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Частини книг з теми "Arctium – physiologie"

1

Gabrielsen, Geir W., and Fridtjof Mehlum. "Thermoregulation and Energetics of Arctic Seabirds." In Physiology of Cold Adaptation in Birds, 137–45. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4757-0031-2_14.

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2

Looney, J. H. H., K. A. Kershaw, E. Nieboer, C. Webber, and P. I. Stetsko. "The Distribution of Uranium and Companion Elements in Lichen Heath Associated with Undisturbed Uranium Deposits in the Canadian Arctic." In Lichen Physiology and Cell Biology, 193–209. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2527-7_14.

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3

Klaassen, Marcel, Claus Bech, Dirkjan Masman, and Guri Slagsvold. "Energy Partitioning in Arctic Tern Chicks (Sterna paradisaea) and Possible Metabolic Adaptations in high Latitude Chicks." In Physiology of Cold Adaptation in Birds, 339–47. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4757-0031-2_36.

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4

Butler, Patrick J., Charles M. Bishop, and Anthony J. Woakes. "Chasing a Wild Goose: Posthatch Growth of Locomotor Muscles and Behavioural Physiology of Migration of an Arctic Goose." In Avian Migration, 527–41. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-662-05957-9_36.

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5

DeVries, Arthur L., and John F. Steffensen. "The Arctic and Antarctic Polar Marine Environments." In Fish Physiology, 1–24. Elsevier, 2005. http://dx.doi.org/10.1016/s1546-5098(04)22001-5.

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6

Junttila, Olavi, and Åse Kaurin. "Environmental Control of Growth Behavior and Cold Hardiness in Arctic and Subarctic Plants." In Low Temperature Stress Physiology in Crops, 91–106. CRC Press, 2018. http://dx.doi.org/10.1201/9781351074186-8.

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Тези доповідей конференцій з теми "Arctium – physiologie"

1

Mak, Lawrence, Brian Farnworth, Eugene H. Wissler, Michel B. DuCharme, Wendell Uglene, Renee Boileau, Pete Hackett, and Andrew Kuczora. "Thermal Requirements for Surviving a Mass Rescue Incident in the Arctic: Preliminary Results." In ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-49471.

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Maritime and air traffic through the Arctic has increased in recent years. Cruise ship and commercial jet liners carry a large number of passengers. With increased traffic, there is a higher probability that a major disaster could occur. Cruise ship and plane accidents could be catastrophic and may require mass rescue. Due to the remote location, limited search and rescue resources, time for these resources to get to the accident location and large number of survivors, the retrieval time could be several days. Therefore, survivors may be required to survive on their own for days while they await rescue. Recognizing that the International Maritime Organization does not have specific thermal performance criteria for liferafts and lifeboats and personal and group survival kits, the Maritime and Arctic Survival Scientific and Engineering Research Team (MASSERT) initiated a research project to improve safety and provide input for advances to regulations. The objective of the project is to investigate if the current thermal protective equipment and preparedness available to people traveling in the Canadian Arctic are adequate for surviving a major air or cruise ship disaster and to identify the minimum thermal protection criteria for survival. This project builds on the results and tools developed in other research projects conducted by the team on thermal protection of liferafts, lifeboats and immersion suits. The project is divided into three major phases — clothing ensemble testing with thermal manikins, a physiology experiment on sustainable shivering duration and ensemble testing in Arctic conditions with human subjects. A numerical model uses these data to simulate survival scenarios. In the first phase of this project, the thermal resistance values of the protective clothing typically available to cruise ship and aircraft passengers were measured using two thermal manikins. The ensembles included Cabin Wear, Deck Wear, Expedition Wear, Abandonment Wear and protective clothing from Canada Forces Major Air Disaster Kit (MAJAID). Tests were conducted on dry and wet ensembles at 5°C and −15°C with and without wind. There is very good agreement between the thermal resistances measured by the two manikins. The differences in thermal resistances observed are likely caused by variations in fit and wrinkles and folds in the ensembles from dressing. With no wind, the thermal resistance is lowest with Cabin Wear and highest with MAJAID clothing inside the down-filled casualty bag. The Expedition Wear, the Abandonment Wear and the MAJAID clothing have about the same thermal resistance. With 7 metre-per-second wind, the thermal resistance of all ensembles decreased significantly by 30% to 70%. These results highlight the importance of having a shelter as a windbreak. For wet clothing ensembles at 5°C, the initial wet thermal resistance was 2 to 2.5 times lower than the dry value, and drying times ranged up to 60 hours. This highlights the importance of staying dry. Preliminary predictions from the numerical model show that the survivors in Expedition Wear, even with sleeping bag and tent, can be mildly hypothermic and need to depend heavily on shivering to maintain thermal balance. In a shelter, the predicted metabolic rate is roughly double the resting rate; it is triple the resting rate without protection from the wind. Further research is required to study shivering fatigue and age effects. Research on mass rescue scenarios for cruise ships and airplanes survivors should ideally involve subjects of both genders and the elderly.
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