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1.
Sandra L. Almeyda Zambrano Eben N. Broadbent Sam Shanee Noga Shanee Anneke Deluycker Michael Steinberg Scott A. Ford Alma Hernndez Jaramillo Robin Fernandez‐Hilario Carolina Lagos Castillo Angelica M. Almeyda Zambrano 《American journal of primatology》2019,81(8)
Habitat loss is one of the main threats to wildlife. Therefore, knowledge of habitat use and preference is essential for the design of conservation strategies and identification of priority sites for the protection of endangered species. The yellow‐tailed woolly monkey (Lagothrix flavicauda Humboldt, 1812), categorized as Critically Endangered on the IUCN Red List, is endemic to montane forests in northern Peru where its habitat is greatly threatened. We assessed how habitat use and preference in L. flavicauda are linked to forest structure and composition. The study took place near La Esperanza, in the Amazonas region, Peru. Our objective was to identify characteristics of habitat most utilized by L. flavicauda to provide information that will be useful for the selection of priority sites for conservation measures. Using presence records collected from May 2013 to February 2014 for one group of L. flavicauda, we classified the study site into three different use zones: low‐use, medium‐use, and high‐use. We assessed forest structure and composition for all use zones using 0.1 ha Gentry vegetation transects. Results show high levels of variation in plant species composition across the three use zones. Plants used as food resources had considerably greater density, dominance, and ecological importance in high‐use zones. High‐use zones presented similar structure to medium‐ and low‐use zones; thus it remains difficult to assess the influence of forest structure on habitat preference. We recommend focusing conservation efforts on areas with a similar floristic composition to the high‐use zones recorded in this study and suggest utilizing key alimentation species for reforestation efforts. 相似文献
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Protoplasts were isolated from mesophyll of axenic cultures of grape, Vitis rotundifolia cv. Summit and V. vinifera cv. Cabernet Sauvignon. Enzymes effective for protoplast isolation were Macerozyme R-10 (0.5% and 0.1%) and Cellulase Onozuka R-10 (1.0% and 0.5%) for V. rotundifolia and V. vinifera, respectively. Polyvinylpyrrolidone and 2-(N-morpholino)ethanesulfonic acid were essential in the isolation media. Protoplasts were purified using flotation/centrifugation. The protoplasts of V. rotundifolia cultured in Gamborg's B5 basal medium with 2.2 M 6-benzyladenine, 4.5 M 2,4-dichlorophenoxyacetic acid and 0.4% agarose gave the best plating efficiency of conditions tried in this study. Cell division occurred within 5 to 6 days and visible microcalli developed within one month. After 6 weeks in culture, microcalli transferred to liquid medium exhibited active callus growth. Protoplasts of V. vinifera cultured under these conditions had similar results.Abbreviations MES
2-(N-morpholino)ethanesulfonic acid monohydrate
- PVP
polyvinylpyrrolidone
- PDS
potassium dextran sulfate
- BA
6-benzyladenine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- FDA
fluorescein diacetate 相似文献
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Jeffrey R. Hazel Rochelle Carpenter 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1985,155(5):597-602
Summary The phospholipid composition of gill tissue was determined in rainbow trout (Salmo gairdneri) undergoing thermal acclimation between 5°C and 20°C for a period of up to 28 days. Proportions of phosphatidylethanolamine
(PE) and cardiolipin (CL) increased during cold acclimation and decreased during warm acclimation; proportions of phosphatidylcholine
(PC) changed in the opposite direction (i.e., decreased during cold acclimation). In contrast, levels of phosphatidylserine,-inositol,
and sphingomyelin did not vary significantly. Thermal modulation of headgroup composition occurred rapidly as reflected by
changes in the ratio of PC-to-PE, which rose significantly from 2.40±0.09 to 2.92±0.09 within 72 h of transfer from 5 to 20°C;
adaptation to 5°C was equally rapid. Proportions of PE changed more rapidly than those of PC during cold adaptation, whereas
the opposite was true during warm acclimation. Both the time course and the direction of the observed changes in phospholipid
composition suggest that such adjustments may contribute to the homeoviscous regulation of membrane properties, particularly
during the initial stages of thermal adaptation. 相似文献
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A mass in the neck, facial pain and cranial nerve palsies are the most common presenting symptoms of malignant tumours of the nasopharynx. Surgery is limited to biopsy for histological diagnosis. External irradiation is the treatment of choice, both for the primary lesion and the regional and distant metastases. Illustrative case histories are presented in detail. Experience over a 20-year period demonstrates that a 20% five-year survival rate has been obtained. 相似文献