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101.
GUTHRIE S. ZIMMERMAN TIMOTHY J. MOSER WILLIAM L. KENDALL PAUL F. DOHERTY JR. GARY C. WHITE DALE F. CASWELL 《The Journal of wildlife management》2009,73(5):710-719
ABSTRACT We assessed variation in reporting probabilities of standard bands among species, populations, harvest locations, and size classes of North American geese to enable estimation of unbiased harvest probabilities. We included reward (US$10, $20, $30, $50, or $100) and control ($0) banded geese from 16 recognized goose populations of 4 species: Canada (Branta canadensis), cackling (B. hutchinsii), Ross's (Chen rossii), and snow geese (C. caerulescens). We incorporated spatially explicit direct recoveries and live recaptures into a multinomial model to estimate reporting, harvest, and band-retention probabilities. We compared various models for estimating harvest probabilities at country (United States vs. Canada), flyway (5 administrative regions), and harvest area (i.e., flyways divided into northern and southern sections) scales. Mean reporting probability of standard bands was 0.73 (95% CI = 0.69–0.77). Point estimates of reporting probabilities for goose populations or spatial units varied from 0.52 to 0.93, but confidence intervals for individual estimates overlapped and model selection indicated that models with species, population, or spatial effects were less parsimonious than those without these effects. Our estimates were similar to recently reported estimates for mallards (Anas platyrhynchos). We provide current harvest probability estimates for these populations using our direct measures of reporting probability, improving the accuracy of previous estimates obtained from recovery probabilities alone. Goose managers and researchers throughout North America can use our reporting probabilities to correct recovery probabilities estimated from standard banding operations for deriving spatially explicit harvest probabilities. 相似文献
102.
CHRISTOPHER R. C. PAUL 《Palaeontology》2011,54(6):1213-1221
Abstract: Thin, radiating, darker bands occur on pyritic internal moulds of the Early Jurassic ammonites Oxynoticeras and Cheltonia from Bishop’s Cleeve, Gloucestershire. They closely resemble true colour patterns preserved in Early Jurassic Calliphylloceras from Kutch, India, and false colour patterns reported in Carboniferous and Triassic ammonoids. Up to five dark bands occur within the body chamber, suggesting that they do not represent serially repeated anatomical structures, but the same feature repeatedly formed during growth. Dark bands are interpreted as traces of black bands deposited on the inside of the shell at the aperture during pauses in growth. The angles between dark bands and between septa correlate strongly in Cheltonia, suggesting that pauses in growth coincided with septal secretion during the chamber formation cycle. There are, however, no other indications that growth was episodic in either genus. 相似文献
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There is considerable current interest in the function of epigenetic mechanisms in neuroplasticity with regard to learning and memory formation and to a range of neural diseases. Previously, we described replication timing on human chromosome 21q in the THP-1 human cell line (2n = 46, XY) and showed that several genes associated with neural diseases, such as the neuronal glutamate receptor subunit GluR-5 (GRIK1) and amyloid precursor protein (APP), were located in regions where replication timing transitioned from early to late S phase. Here, we compared replication timing of all known human glutamate receptor genes (26 genes in total) and APP in 6 different human cell lines including human neuron-related cell lines. Replication timings were obtained by integrating our previously reported data with new data generated here and information from the online database ReplicationDomain. We found that many of the glutamate receptor genes were clearly located in replication timing transition zones in neural precursor cells, but this relationship was less clear in embryonic stem cells before neural differentiation; in the latter, the genes were often located in later replication timing zones that displayed DNA hypermethylation. Analysis of selected large glutamate receptor genes (>200 kb), and of APP, showed that their precise replication timing patterns differed among the cell lines. We propose that the transition zones of DNA replication timing are altered by epigenetic mechanisms, and that these changes may affect the neuroplasticity that is important to memory and learning, and may also have a role in the development of neural diseases. 相似文献
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Genomic in situ hybridization offers a powerful tool for investigating genome organisation and evolution of taxa known, or suspected, to be allopolyploids. The question of the diploid progenitors of cultivated peanut (Arachis hypogaea, 2n=4x=40) has been the subject of numerous studies at cytogenetical, cytochemical, biochemical and molecular levels, but no definitive conclusions have been reached. The biotinylated total genomic DNA from potential diploidArachis species were separately hybridized in situ to root tip chromosomes ofA. hypogaea and wild speciesA. monticola (2n=4x=40) without or mixed with an excess of unlabelled DNA from the species not used as a probe. Among the range of different species combinations used, the strong and uniform signals given by labelledA. ipaensis DNA when hybridized toA. hypogaea andA. monticola in combination with unlabelledA. villosa DNA indicates that overall molecular composition of twenty chromosomes ofA. hypogaea andA. monticola is very similar toA. ipaensis chromosomes. ProbingA. hypogaea andA. monticola chromosomes with labelled genomic DNA fromA. villosa mixed with unlabelled DNA fromA. ipaensis likewise labelled strongly and uniformly the other twenty chromosomes. BarringA. ipaensis, all the diploidArachis species presently investigated had characteristic centromeric bands in the twenty chromosomes within the complement indicating a clear division ofA. ipaensis from other species. InA. hypogaea andA. monticola only twenty chromosomes showed centromeric bands. These results (i) confirm the allopolyploid nature ofA. hypogaea andA. monticola, (ii) strongly support the view that wildA. monticola and cultivatedA. hypogaea are very closely related, and (iii) indicate thatA. villosa andA. ipaensis are the diploid wild progenitors of the tetraploid species studied. The present results also reveal that the nucleolus organizing region (NOR) originating fromA. villosa alone is expressed in the two tetraploid species. 相似文献
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代表活性污泥中苯酚降解菌群的ERIC-PCR产物片段的多态性 总被引:10,自引:1,他引:10
对可能代表活性污泥中两个时期的主要苯酚降解菌群的:ERIC-PCR指纹图谱中的两条2.1kb的条带(P1和P8)中的DNA片段进行克隆、转化,得到193个转化子。.HinfⅠ物理图谱分析得到35种酶切类型,将两端各进行1次测序后,同源性大于90%的克隆归为一类,共得到10种序列类型。对各类型的代表克隆进行了全长测序,5种类型为P1条带所有,3种类型为P8所有,二者共享的类型为2种,丰度最高的片段为S3,P1条带中76.3%的转化子和P8条带中66.7%转化子属该类型。对所得序列进行检索分析,它们与GenBank中已知基因序列均无显著同源性。用S3特异性引物对活性污泥样品及其它在LB、dCGY、MP和FWM培养基上的回收菌进:行扩增,除LB上的回收菌没有显示目的条带外,活性污泥和其回收菌中均检测到带有该基因组片段的菌种的存在。研究为专一性分离降酚活性污泥中的优势菌提供了分子探针。 相似文献