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81.
Seasonal dynamics of agonistic behavior and hormones in an ex situ all‐male colony of large flying foxes 下载免费PDF全文
Hani D. Freeman Michelle Wood Mandi W. Schook Katherine A. Leighty Shana R. Lavin Susan Wiebe Tracy E. Blowers Rachel Daneault Natalie Mylniczenko Catharine J. Wheaton 《Zoo biology》2018,37(4):213-222
Large flying foxes (Pteropus vampyrus) are a socially complex species. In situ colonies typically comprise thousands of individuals in small harems of one male to many females. In ex situ environments, all‐male colonies are becoming more common due to a surplus of males in the population. There is limited information describing the hormonal and behavioral patterns of all‐male colonies during the breeding season. We assessed seasonal changes in hormones and behavior in an all‐male colony of 12 large flying foxes at Disney's Animal Kingdom®. We validated hormone assays using morning urine and fecal samples to assess seasonal changes in excreted immunoreactive testosterone and glucocorticoid metabolites. We collected behavior data using an all‐occurrence method, recording agonistic behaviors related to territorial defense (hooking, biting, wing flexing, vocalizing, and wrestling), and sexual behavior (mounting and frontal grabbing). Results indicated that (i) we could reliably measure testosterone and glucocorticoid metabolites concentrations from fecal and urine samples collected from individual bats; (ii) there were distinct relationships between changes in levels of agonism and hormone concentrations throughout the year; and (iii) three agonistic behaviors (chasing, wrestling, and open‐mouth threat) peaked prior to the increase in testosterone and glucocorticoid hormones measured during the breeding season. These three behaviors could potentially be used as early indicators to signal the onset of the breeding season and allow time to implement ex situ management changes to reduce the incidence of agonism between individuals. 相似文献
82.
JINDŘIŠKA BOJKOVÁ KLÁRA KOMPRDOVÁ TOMÁŠ SOLDÁN SVĚTLANA ZAHRÁDKOVÁ 《Freshwater Biology》2012,57(12):2550-2567
1. Rapid expansion and intensification of anthropogenic activities in the 20th century has caused profound changes in freshwater assemblages. Unfortunately, knowledge of the extent and causes of species loss (SL) is limited due to the lack of reliable historical data. An unusual data set allows us to compare changes in the most sensitive of aquatic insect orders, the Plecoptera, at some 170 locations in the Czech Republic between two time periods, 1955–1960 and 2006–2010. Historical data (1890–1911) on assemblages of six lowland rivers allow us to infer even earlier changes. 2. Regional stonefly diversity decreased in the first half of the 20th century. Streams at lower altitudes lost a substantial number of species, which were never recovered. In the second half of the century, large‐scale anthropogenic pressure caused SL in all habitats, leading to a dissimilarity of contemporary and previous assemblages. The greatest changes were found at sites affected by organic pollution and a mixture of organic pollution and channelisation or impoundment. Colonisation of new habitats was observed in only three of the 80 species evaluated. 3. Species of moderate habitat specialisation and tolerance to organic pollution were most likely to be lost. Those with narrow specialisations in protected habitats were present in both historical and contemporary collections. 4. Contemporary assemblages are the consequence of more than a 100 years of anthropogenic impacts. In particular, streams at lower altitude and draining intensively exploited landscapes host a mere fragment of the original species complement. Most stonefly species are less frequently present than before, although their assemblages remain almost intact in near‐natural mountain streams. Our analyses demonstrate dramatic restriction of species ranges and, in some cases, apparent changes in altitudinal preference throughout the area. 相似文献
83.
Bucklin Ann; Smolenack Sara B.; Bentley Alyssa M.; Wiebe Peter H. 《Journal of plankton research》1997,19(11):1763-1781
Population genetic structure and patterns of gene flow are describedfor the euphausiid, Meganyctiphanes norvegica, in the NW AtlanticOcean based on DNA sequence variation of two regions of mitochondrialDNA (mtDNA). DNA sequences were determined for portions of cytochromeoxidase I (COI; 400 base pairs; 76 individuals) and cytochromeb (CYB; 300 base pairs; 101 individuals) for euphausiids collectedfrom the Gulf of Maine in 1991, the Gulf of St Lawrence in 1993and 1994, the Scotian Shelf in 1994, and Georges Bank in 1994.For comparison, M.norvegica collected from the fjords of westernNorway in 1992 were sequenced for COI (20 individuals) and CYB(18 individuals). COI was less variable than CYB, based on bothhaplotype (h=0.6847 for COI; 0.9077 for CYB) and nucleotidediversities ( 相似文献
84.
85.
John W Hawes Kevin L Knudtson Helaman Escobar George S Grills Timothy C Hunter Emily Jackson-Machelski Heather Lin David S Needleman Rashmi Pershad Glenis J Wiebe 《Journal of biomolecular techniques》2006,17(2):138-144
The DNA Sequencing Research Group (DSRG) of the ABRF conducted a study to assess the ability of DNA sequencing core facilities to successfully sequence a set of well-defined templates containing difficult repeats. The aim of this study was to determine whether repetitive templates could be sequenced accurately by using equipment and chemistries currently utilized in participating sequencing laboratories. The effects of primer and template concentrations, sequencing chemistries, additives, and instrument formats on the ability to successfully sequence repeat elements were examined. The first part of this study was an analysis of the results of 361 chromatograms from participants representing 40 different laboratories who attempted to sequence a panel of difficult-to-sequence templates using their best in-house protocols. The second part of this study was a smaller multi-laboratory evaluation of a single robust protocol with the same panel of templates. This study provides a measure of the potential success of different approaches to sequencing across homopolymer tracts and repetitive elements. 相似文献
86.
Jessica Perugini Laura Bordoni Wiebe Venema Samantha Acciarini Saverio Cinti Rosita Gabbianelli Antonio Giordano 《Journal of cellular physiology》2019,234(3):2031-2036
In the mammalian adipose organ cold exposure not only activates typical brown adipose tissue, but also induces browning, that is the formation of thermogenic multilocular adipocytes in white, or predominantly white, adipose depots such as subcutaneous fat. Unlike typical brown adipocytes, newly formed thermogenic adipocytes have been reported not to express the gene zinc finger of the cerebellum 1 (Zic1). Here, a time course approach enabled us to document a significant increase in Zic1 messenger RNA in inguinal subcutaneous fat from acutely (24 hr) cold-exposed mice, which was paralleled by an increase in multilocular and paucilocular uncoupling protein 1-positive adipocytes and in parenchymal noradrenergic innervation. This transient, depot-specific molecular signature was associated not to Zic1 promoter demethylation, but to chromatin remodeling through an H3K9me3 histone modification. These findings challenge the notion that Zic1 is exclusively expressed by typical brown adipocytes and suggest its involvement in brown adipocyte precursor differentiation and/or white-to-brown adipocyte transdifferentiation. 相似文献
87.
Pawlak KJ Zhang G Wiebe JP 《The Journal of steroid biochemistry and molecular biology》2005,97(3):278-288
88.
O L Posukh V P Wiebe R I Sukernik L P Osipova T M Karaphet M S Schanfield 《Human biology; an international record of research》1990,62(4):457-465
Three territorial subgroups of reindeer breeders, fishermen, and fur hunters living under conditions of partial isolation in remote parts of the Yakut ASSR, have been investigated with respect to polymorphic genetic systems. Analysis of covariance matrices containing allele frequencies in an array of 12 loci for a large sample of Evens, Nganasans, and reindeer Chukchi indicates that the genetic relationships support known phylogenetic, linguistic, and historical events. 相似文献
89.
1-(2-Fluoro-4-iodo-2,4-dideoxy-beta-L-xylopyranosyl)-2-nitroimidazole (FIAZP) has been synthesized and labeled with radioiodine (125I). Radioiodinated FIAZP is one of a series of sugar-coupled 2-nitroimidazoles developed in our laboratory as probes for noninvasive scintigraphic assessment of tumor hypoxia. An in vivo biodistribution study with [125I]FIAZP in the murine BALB/c EMT-6 tumor model showed a tumor-to-blood ratio of 6, 24 h after injection, with 0.5% of the injected dose present per gram of tumor. These values are several times higher than the respective ratios and distribution values in any of the organs, with the exception of liver. Radioactivity from tissues other than tumor and liver declined with time, following the decline of blood radioactivity. Rapid whole-body elimination of radioactivity was observed (> 96% in 24 h). The thyroid showed little uptake of radioactivity, indicating minimal in vivo deiodination. 1-(2-Fluoro-4-iodo-2,4-dideoxy-beta-L-xylopranosyl)-2-nitroimidazo le appears to undergo hypoxia-dependent binding in tumor tissue at levels comparable to those of other sugar-coupled 2-nitroimidazoles. The potential for imaging with this compound is discussed. 相似文献
90.
At pH 5.8, highly branched (colonial) mutants appear in glucose-limited chemostat cultures of Fusarium graminearum A3/5 after ca. 400 h (ca. 107 generations) of growth. The appearance of these mutants was delayed by up to 144 h (45 generations) when the culture was switched at intervals of 120 h between pH 4.8 and 6.6. The concentration of cycloheximide-resistant macroconidia in the culture was used as an indicator of the periodic selection of advantageous mutants and it was found that, in chemostat populations subjected to pH oscillations, the interval (210 +/- 20 h) between peaks was nearly double that observed in chemostat populations cultured at constant pH (124 +/- 12 h at constant pH 5.8 and 120 h +/- 17 h at constant pH 4.5), indicating that the population evolved more slowly under oscillating pH than under constant pH. When grown in mixed culture with the parental strain (A3/5), the selective advantage of two colonial mutants isolated from chemostat cultures grown under conditions of oscillating pH was found to be pH dependent. Compared to cultures grown at constant pH 5.8, a delay of ca. 312 h (87 generations) in the appearance of colonial mutants was observed when F. graminearum A3/5 was grown in glucose-limited chemostat culture at constant pH 4.5. (c) 1996 John Wiley & Sons, Inc. 相似文献