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941.
Desmond A. Mackell Michael L. Casazza Cory T. Overton J. Patrick Donnelly David Olson Fiona McDuie Joshua T. Ackerman John M. Eadie 《Ecology and evolution》2021,11(20):14056
Identifying migration routes and fall stopover sites of Cinnamon Teal (Spatula cyanoptera septentrionalium) can provide a spatial guide to management and conservation efforts, and address vulnerabilities in wetland networks that support migratory waterbirds. Using high spatiotemporal resolution GPS‐GSM transmitters, we analyzed 61 fall migration tracks across western North America during our three‐year study (2017–2019). We marked Cinnamon Teal primarily during spring/summer in important breeding and molting regions across seven states (California, Oregon, Washington, Idaho, Utah, Colorado, and Nevada). We assessed fall migration routes and timing, detected 186 fall stopover sites, and identified specific North American ecoregions where sites were located. We classified underlying land cover for each stopover site and measured habitat selection for 12 land cover types within each ecoregion. Cinnamon Teal selected a variety of flooded habitats including natural, riparian, tidal, and managed wetlands; wet agriculture (including irrigation ditches, flooded fields, and stock ponds); wastewater sites; and golf and urban ponds. Wet agriculture was the most used habitat type (29.8% of stopover locations), and over 72% of stopover locations were on private land. Relatively scarce habitats such as wastewater ponds, tidal marsh, and golf and urban ponds were highly selected in specific ecoregions. In contrast, dry non‐habitat across all ecoregions, and dry agriculture in the Cold Deserts and Mediterranean California ecoregions, was consistently avoided. Resources used by Cinnamon Teal often reflected wetland availability across the west and emphasize their adaptability to dynamic resource conditions in arid landscapes. Our results provide much needed information on spatial and temporal resource use by Cinnamon Teal during migration and indicate important wetland habitats for migrating waterfowl in the western United States. 相似文献
942.
Sangeeta Mangubhai Ayron M. Strauch David O. Obura Gregory Stone Randi D. Rotjan 《Reviews in Fish Biology and Fisheries》2014,24(2):505-518
Climate change-related disturbances are increasingly recognized as critical threats to biodiversity and species abundance. On coral reefs, climate disturbances have known consequences for reef fishes, but it is often difficult to isolate the effect of coral bleaching from preceding or simultaneous disturbances such as fishing, pollution, and habitat loss. In this study, pre-bleaching surveys of fish family assemblages in the remote Phoenix Islands in 2002 are compared to post-bleaching in 2005, following severe thermal stress. Post-bleaching, total coral cover decreased substantially, as did the combined abundance of all fish families. Yet, changes in abundance for specific fish families were not uniform, and varied greatly from site to site. Of the 13 fish families examined, 3 exhibited significant changes in abundance from 2002 to 2005, regardless of site (Carangidae, Chaetodontidae, and serranid subfamily Epinephelinae). For these families, we explored whether changes in abundance were related to island type (island vs atoll) and/or declining coral cover (percent change). Carangidae on islands experienced larger changes in abundance than those on atolls, though declines in abundance over time were not associated with changes in live coral cover. In contrast, for Chaetodontidae, declines in abundance over time were most dramatic on atolls, and were also associated with changes in live coral cover. The remoteness of the Phoenix Islands excludes many typical local anthropogenic stressors as drivers of short-term changes; observed changes are instead more likely attributed to natural variation in fish populations, or associated with coral loss following the 2002–2003 major thermal stress event. 相似文献
943.
Monoclonal antibodies (MAbs) were developed against recombinant ovine interleukin-5 (IL-5) produced in the baculovirus expression vector system. One MAb, D11 (isotype IgG1), neutralised the activity of both recombinant and native sources of IL-5 in a biological assay (Baf cell assay) but was only weakly reactive in immunocytochemistry. Conversely, a second MAb, A8 (isotype IgA), successfully detected IL-5 in immunocytochemistry but did not display neutralising activity. The development of these MAbs will enable the assay of ovine IL-5 in vitro and permit studies into the role of hypersensitivity reactions in sheep by neutralisation of IL-5 in vivo. 相似文献
944.
945.
Pascal Fournier Christian Maizeret David Jimenez Jean-Pierre Chusseau Stéphane Aulagnier François Spitz 《Acta theriologica》2007,52(1):1-12
The European minkMustela lutreola Linnaeus, 1761 and the European polecatMustela putorius Linnaeus, 1758 are related species sympatric in southwestern France. The European mink is rapidly disappearing whereas the
polecat maintains good populations. Seasonal habitat use of both species was compared in the Landes de Gascogne region to
identify if some vulnerability factors of the European mink were associated with habitats occupied by this mustelid. Potential
habitats were mapped using a satellite picture and 12 main types of habitats were defined. Animal locations were recorded
by radiotracking 9 European mink and 14 polecats from March 1996 to August 1999. Resting animals were located by triangulation,
and, when possible, resting places were described. Animals in activity were tracked by continuous monitoring. Data collected
revealed a strong preference of European mink for flooded habitats, particularly open marshes, flooded woodlands and moorlands.
They seldom left the corridor of the riparian forest and their resting places were mainly in flooded environments, above ground
(under herbs or bushes) or in cavities between tree roots. European polecats were less tightly linked to wetlands. Most of
their locations were in the pine forests outside the valleys and their resting places were mainly in burrows. The strong specialisation
of European mink in aquatic habitats is probably one of the main reasons for its decline because wetlands suffer drastic damages
throughout all of its range. Maintaining adequate water levels is crucial for satisfying habitat requirements of mink. 相似文献
946.
Rollo EE Hempson SJ Bansal A Tsao E Habib I Rittling SR Denhardt DT Mackow ER Shaw RD 《Journal of virology》2005,79(6):3509-3516
947.
Human pluripotent stem cells produce natural killer cells that mediate anti-HIV-1 activity by utilizing diverse cellular mechanisms 总被引:1,自引:0,他引:1
Ni Z Knorr DA Clouser CL Hexum MK Southern P Mansky LM Park IH Kaufman DS 《Journal of virology》2011,85(1):43-50
Cell-based therapies against HIV/AIDS have been gaining increased interest. Natural killer (NK) cells are a key component of the innate immune system with the ability to kill diverse tumor cells and virus-infected cells. While NK cells have been shown to play an important role in the control of HIV-1 replication, their functional activities are often compromised in HIV-1-infected individuals. We have previously demonstrated the derivation of NK cells from human embryonic stem cells (hESCs) with the ability to potently kill multiple types of tumor cells both in vitro and in vivo. We now demonstrate the derivation of functional NK cells from human induced pluripotent stem cells (iPSCs). More importantly, both hESC- and iPSC-derived NK cells are able to inhibit HIV-1 NL4-3 infection of CEM-GFP cells. Additional studies using HIV-1-infected human primary CD4(+) T cells illustrated that hESC- and iPSC-derived NK cells suppress HIV-1 infection by at least three distinct cellular mechanisms: killing of infected targets through direct lysis, antibody-dependent cellular cytotoxicity, and production of chemokines and cytokines. Our results establish the potential to utilize hESC- and iPSC-derived NK cells to better understand anti-HIV-1 immunity and provide a novel cellular immunotherapeutic approach to treat HIV/AIDS. 相似文献
948.
949.